1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 12
6 * "info breakpoints" now displays enabled breakpoint locations of
7 disabled breakpoints as in the "y-" state. For example:
10 Num Type Disp Enb Address What
11 1 breakpoint keep n <MULTIPLE>
12 1.1 y- 0x00000000000011b6 in ...
13 1.2 y- 0x00000000000011c2 in ...
14 1.3 n 0x00000000000011ce in ...
16 * Support for Thread Local Storage (TLS) variables on FreeBSD arm and
17 aarch64 architectures.
19 * GDB now supports hardware watchpoints on FreeBSD/Aarch64.
21 * Remove support for building against Python 2, it is now only possible to
22 build GDB against Python 3.
24 * DBX mode has been removed.
26 * GDB now honours the DWARF prologue_end line-table entry flag the compiler can
27 emit to indicate where a breakpoint should be placed to break in a function
32 maintenance set ignore-prologue-end-flag on|off
33 maintenance show ignore-prologue-end-flag
34 This setting, which is off by default, controls whether GDB ignores the
35 PROLOGUE-END flag from the line-table when skipping prologue. This can be
36 used to force GDB to use prologue analyzers if the line-table is constructed
37 from erroneous debug information.
41 maintenance info line-table
42 Add a PROLOGUE-END column to the output which indicates that an
43 entry corresponds to an address where a breakpoint should be placed
44 to be at the first instruction past a function's prologue.
48 ** GDB will now reformat the doc string for gdb.Command and
49 gdb.Parameter sub-classes to remove unnecessary leading
50 whitespace from each line before using the string as the help
53 ** New function gdb.format_address(ADDRESS, PROGSPACE, ARCHITECTURE),
54 that formats ADDRESS as 'address <symbol+offset>', where symbol is
55 looked up in PROGSPACE, and ARCHITECTURE is used to format address.
56 This is the same format that GDB uses when printing address, symbol,
57 and offset information from the disassembler.
59 ** New function gdb.current_language that returns the name of the
60 current language. Unlike gdb.parameter('language'), this will
63 ** New method gdb.Frame.language that returns the name of the
68 * DBX mode is deprecated, and will be removed in GDB 13
70 * GDB 12 is the last release of GDB that will support building against
71 Python 2. From GDB 13, it will only be possible to build GDB itself
72 with Python 3 support.
74 * The disable-randomization setting now works on Windows.
76 * Improved C++ template support
78 GDB now treats functions/types involving C++ templates like it does function
79 overloads. Users may omit parameter lists to set breakpoints on families of
80 template functions, including types/functions composed of multiple template types:
82 (gdb) break template_func(template_1, int)
84 The above will set breakpoints at every function `template_func' where
85 the first function parameter is any template type named `template_1' and
86 the second function parameter is `int'.
88 TAB completion also gains similar improvements.
90 * The FreeBSD native target now supports async mode.
96 Enable or disable multithreaded symbol loading. This is enabled
97 by default, but passing --disable-threading or --enable-threading=no
98 to configure will disable it.
100 Disabling this can cause a performance penalty when there are a lot of
101 symbols to load, but is useful for debugging purposes.
105 maint set backtrace-on-fatal-signal on|off
106 maint show backtrace-on-fatal-signal
107 This setting is 'on' by default. When 'on' GDB will print a limited
108 backtrace to stderr in the situation where GDB terminates with a
109 fatal signal. This only supported on some platforms where the
110 backtrace and backtrace_symbols_fd functions are available.
112 set source open on|off
114 This setting, which is on by default, controls whether GDB will try
115 to open source code files. Switching this off will stop GDB trying
116 to open and read source code files, which can be useful if the files
117 are located over a slow network connection.
121 These are now deprecated aliases for "set max-value-size" and
122 "show max-value-size".
124 task apply [all | TASK-IDS...] [FLAG]... COMMAND
125 Like "thread apply", but applies COMMAND to Ada tasks.
128 Watchpoints can now be restricted to a specific Ada task.
130 maint set internal-error backtrace on|off
131 maint show internal-error backtrace
132 maint set internal-warning backtrace on|off
133 maint show internal-warning backtrace
134 GDB can now print a backtrace of itself when it encounters either an
135 internal-error, or an internal-warning. This is on by default for
136 internal-error and off by default for internal-warning.
139 Deprecated and replaced by "set logging enabled on|off".
141 set logging enabled on|off
143 These commands set or show whether logging is enabled or disabled.
146 You can now exit GDB by using the new command "exit", in addition to
147 the existing "quit" command.
149 set debug threads on|off
151 Print additional debug messages about thread creation and deletion.
153 set debug linux-nat on|off
155 These new commands replaced the old 'set debug lin-lwp' and 'show
156 debug lin-lwp' respectively. Turning this setting on prints debug
157 messages relating to GDB's handling of native Linux inferiors.
159 maint flush source-cache
160 Flush the contents of the source code cache.
162 maint set gnu-source-highlight enabled on|off
163 maint show gnu-source-highlight enabled
164 Whether GDB should use the GNU Source Highlight library for adding
165 styling to source code. When off, the library will not be used, even
166 when available. When GNU Source Highlight isn't used, or can't add
167 styling to a particular source file, then the Python Pygments
168 library will be used instead.
170 set suppress-cli-notifications (on|off)
171 show suppress-cli-notifications
172 This controls whether printing the notifications is suppressed for CLI.
173 CLI notifications occur when you change the selected context
174 (i.e., the current inferior, thread and/or the frame), or when
175 the program being debugged stops (e.g., because of hitting a
176 breakpoint, completing source-stepping, an interrupt, etc.).
178 set style disassembler enabled on|off
179 show style disassembler enabled
180 If GDB is compiled with Python support, and the Python Pygments
181 package is available, then, when this setting is on, disassembler
182 output will have styling applied.
184 set ada source-charset
185 show ada source-charset
186 Set the character set encoding that is assumed for Ada symbols. Valid
187 values for this follow the values that can be passed to the GNAT
188 compiler via the '-gnati' option. The default is ISO-8859-1.
194 These are the new names for the old 'layout', 'focus', 'refresh',
195 and 'winheight' tui commands respectively. The old names still
196 exist as aliases to these new commands.
200 The new command 'tui window width', and the alias 'winwidth' allow
201 the width of a tui window to be adjusted when windows are laid out
206 Control the display of debug output about GDB's tui.
211 Printing of floating-point values with base-modifying formats like
212 /x has been changed to display the underlying bytes of the value in
213 the desired base. This was GDB's documented behavior, but was never
214 implemented correctly.
217 This command can now print a reply, if the reply includes
218 non-printable characters. Any non-printable characters are printed
219 as escaped hex, e.g. \x?? where '??' is replaces with the value of
220 the non-printable character.
223 The clone-inferior command now ensures that the TTY, CMD and ARGS
224 settings are copied from the original inferior to the new one.
225 All modifications to the environment variables done using the 'set
226 environment' or 'unset environment' commands are also copied to the new
229 set debug lin-lwp on|off
231 These commands have been removed from GDB. The new command 'set
232 debug linux-nat' and 'show debug linux-nat' should be used
236 This command now includes information about the width of the tui
237 windows in its output.
243 These commands are now aliases for the 'tui layout', 'tui focus',
244 'tui refresh', and 'tui window height' commands respectively.
246 * GDB's Ada parser now supports an extension for specifying the exact
247 byte contents of a floating-point literal. This can be useful for
248 setting floating-point registers to a precise value without loss of
249 precision. The syntax is an extension of the based literal syntax.
250 Use, e.g., "16lf#0123abcd#" -- the number of "l"s controls the width
251 of the floating-point type, and the "f" is the marker for floating
256 ** The '-add-inferior' with no option flags now inherits the
257 connection of the current inferior, this restores the behaviour of
258 GDB as it was prior to GDB 10.
260 ** The '-add-inferior' command now accepts a '--no-connection'
261 option, which causes the new inferior to start without a
266 GNU/Linux/LoongArch loongarch*-*-linux*
274 ** New function gdb.add_history(), which takes a gdb.Value object
275 and adds the value it represents to GDB's history list. An
276 integer, the index of the new item in the history list, is
279 ** New function gdb.history_count(), which returns the number of
280 values in GDB's value history.
282 ** New gdb.events.gdb_exiting event. This event is called with a
283 gdb.GdbExitingEvent object which has the read-only attribute
284 'exit_code', which contains the value of the GDB exit code. This
285 event is triggered once GDB decides it is going to exit, but
286 before GDB starts to clean up its internal state.
288 ** New function gdb.architecture_names(), which returns a list
289 containing all of the possible Architecture.name() values. Each
292 ** New function gdb.Architecture.integer_type(), which returns an
293 integer type given a size and a signed-ness.
295 ** New gdb.TargetConnection object type that represents a connection
296 (as displayed by the 'info connections' command). A sub-class,
297 gdb.RemoteTargetConnection, is used to represent 'remote' and
298 'extended-remote' connections.
300 ** The gdb.Inferior type now has a 'connection' property which is an
301 instance of gdb.TargetConnection, the connection used by this
302 inferior. This can be None if the inferior has no connection.
304 ** New 'gdb.events.connection_removed' event registry, which emits a
305 'gdb.ConnectionEvent' when a connection is removed from GDB.
306 This event has a 'connection' property, a gdb.TargetConnection
307 object for the connection being removed.
309 ** New gdb.connections() function that returns a list of all
310 currently active connections.
312 ** New gdb.RemoteTargetConnection.send_packet(PACKET) method. This
313 is equivalent to the existing 'maint packet' CLI command; it
314 allows a user specified packet to be sent to the remote target.
316 ** New function gdb.host_charset(), returns a string, which is the
317 name of the current host charset.
319 ** New gdb.set_parameter(NAME, VALUE). This sets the gdb parameter
322 ** New gdb.with_parameter(NAME, VALUE). This returns a context
323 manager that temporarily sets the gdb parameter NAME to VALUE,
324 then resets it when the context is exited.
326 ** The gdb.Value.format_string method now takes a 'styling'
327 argument, which is a boolean. When true, the returned string can
328 include escape sequences to apply styling. The styling will only
329 be present if styling is otherwise turned on in GDB (see 'help
330 set styling'). When false, which is the default if the argument
331 is not given, then no styling is applied to the returned string.
333 ** New read-only attribute gdb.InferiorThread.details, which is
334 either a string, containing additional, target specific thread
335 state information, or None, if there is no such additional
338 ** New read-only attribute gdb.Type.is_scalar, which is True for
339 scalar types, and False for all other types.
341 ** New read-only attribute gdb.Type.is_signed. This attribute
342 should only be read when Type.is_scalar is True, and will be True
343 for signed types, and False for all other types. Attempting to
344 read this attribute for non-scalar types will raise a ValueError.
346 ** It is now possible to add GDB/MI commands implemented in Python.
348 * New features in the GDB remote stub, GDBserver
350 ** GDBserver is now supported on OpenRISC GNU/Linux.
352 * New native configurations
354 GNU/Linux/OpenRISC or1k*-*-linux*
356 *** Changes in GDB 11
358 * The 'set disassembler-options' command now supports specifying options
361 * GDB now supports general memory tagging functionality if the underlying
362 architecture supports the proper primitives and hooks. Currently this is
363 enabled only for AArch64 MTE.
367 - Additional information when the inferior crashes with a SIGSEGV caused by
368 a memory tag violation.
370 - A new modifier 'm' for the "x" command, which displays allocation tags for a
371 particular memory range.
373 - Display of memory tag mismatches by "print", for addresses and
374 pointers, if memory tagging is supported by the architecture.
376 * Building GDB now requires GMP (The GNU Multiple Precision Arithmetic
381 ** '-break-insert --qualified' and '-dprintf-insert --qualified'
383 The MI -break-insert and -dprintf-insert commands now support a
384 new "--qualified" option that makes GDB interpret a specified
385 function name as a complete fully-qualified name. This is the
386 equivalent of the CLI's "break -qualified" and "dprintf
389 ** '-break-insert --force-condition' and '-dprintf-insert --force-condition'
391 The MI -break-insert and -dprintf-insert commands now support a
392 '--force-condition' flag to forcibly define a condition even when
393 the condition is invalid at all locations of the breakpoint. This
394 is equivalent to the '-force-condition' flag of the CLI's "break"
397 ** '-break-condition --force'
399 The MI -break-condition command now supports a '--force' flag to
400 forcibly define a condition even when the condition is invalid at
401 all locations of the selected breakpoint. This is equivalent to
402 the '-force' flag of the CLI's "cond" command.
404 ** '-file-list-exec-source-files [--group-by-objfile]
405 [--basename | --dirname]
408 The existing -file-list-exec-source-files command now takes an
409 optional REGEXP which is used to filter the source files that are
410 included in the results.
412 By default REGEXP is matched against the full filename of the
413 source file. When one of --basename or --dirname is given then
414 REGEXP is only matched against the specified part of the full
417 When the optional --group-by-objfile flag is used the output
418 format is changed, the results are now a list of object files
419 (executable and libraries) with the source files that are
420 associated with each object file.
422 The results from -file-list-exec-source-files now include a
423 'debug-fully-read' field which takes the value 'true' or 'false'.
424 A 'true' value indicates the source file is from a compilation
425 unit that has had its debug information fully read in by GDB, a
426 value of 'false' indicates GDB has only performed a partial scan
427 of the debug information so far.
429 * GDB now supports core file debugging for x86_64 Cygwin programs.
431 * GDB will now look for the .gdbinit file in a config directory before
432 looking for ~/.gdbinit. The file is searched for in the following
433 locations: $XDG_CONFIG_HOME/gdb/gdbinit, $HOME/.config/gdb/gdbinit,
434 $HOME/.gdbinit. On Apple hosts the search order is instead:
435 $HOME/Library/Preferences/gdb/gdbinit, $HOME/.gdbinit.
437 * GDB now supports fixed point types which are described in DWARF
438 as base types with a fixed-point encoding. Additionally, support
439 for the DW_AT_GNU_numerator and DW_AT_GNU_denominator has also
442 For Ada, this allows support for fixed point types without requiring
443 the use of the GNAT encoding (based on information added to the type's
444 name following a GNAT-specific format).
446 * GDB will now load and process commands from ~/.config/gdb/gdbearlyinit
447 or ~/.gdbearlyinit if these files are present. These files are
448 processed earlier than any of the other initialization files and
449 can affect parts of GDB's startup that previously had already been
450 completed before the initialization files were read, for example
451 styling of the initial GDB greeting.
453 * GDB now has two new options "--early-init-command" and
454 "--early-init-eval-command" with corresponding short options "-eix"
455 and "-eiex" that allow options (that would normally appear in a
456 gdbearlyinit file) to be passed on the command line.
458 * For RISC-V targets, the target feature "org.gnu.gdb.riscv.vector" is
459 now understood by GDB, and can be used to describe the vector
460 registers of a target. The precise requirements of this register
461 feature are documented in the GDB manual.
463 * For ARM targets, the "org.gnu.gdb.arm.m-profile-mve" feature is now
464 supported by GDB and describes a new VPR register from the ARM MVE
465 (Helium) extension. See the GDB manual for more information.
469 ** TUI windows now support mouse actions. The mouse wheel scrolls
470 the appropriate window.
472 ** Key combinations that do not have a specific action on the
473 focused window are passed to GDB. For example, you now can use
474 Ctrl-Left/Ctrl-Right to move between words in the command window
475 regardless of which window is in focus. Previously you would
476 need to focus on the command window for such key combinations to
482 show debug event-loop
483 Control the display of debug output about GDB's event loop.
485 set print memory-tag-violations
486 show print memory-tag-violations
487 Control whether to display additional information about memory tag violations
488 when printing pointers and addresses. Architecture support for memory
489 tagging is required for this option to have an effect.
491 maintenance flush symbol-cache
492 maintenance flush register-cache
493 These new commands are equivalent to the already existing commands
494 'maintenance flush-symbol-cache' and 'flushregs' respectively.
496 maintenance flush dcache
497 A new command to flush the dcache.
499 maintenance info target-sections
500 Print GDB's internal target sections table.
503 Print the JIT code objects in the inferior known to GDB.
505 memory-tag show-logical-tag POINTER
506 Print the logical tag for POINTER.
507 memory-tag with-logical-tag POINTER TAG
508 Print POINTER with logical tag TAG.
509 memory-tag show-allocation-tag ADDRESS
510 Print the allocation tag for ADDRESS.
511 memory-tag set-allocation-tag ADDRESS LENGTH TAGS
512 Set the allocation tag for [ADDRESS, ADDRESS + LENGTH) to TAGS.
513 memory-tag check POINTER
514 Validate that POINTER's logical tag matches the allocation tag.
516 set startup-quietly on|off
518 When 'on', this causes GDB to act as if "-silent" were passed on the
519 command line. This command needs to be added to an early
520 initialization file (e.g. ~/.config/gdb/gdbearlyinit) in order to
523 set print type hex on|off
525 When 'on', the 'ptype' command uses hexadecimal notation to print sizes
526 and offsets of struct members. When 'off', decimal notation is used.
528 set python ignore-environment on|off
529 show python ignore-environment
530 When 'on', this causes GDB's builtin Python to ignore any
531 environment variables that would otherwise affect how Python
532 behaves. This command needs to be added to an early initialization
533 file (e.g. ~/.config/gdb/gdbearlyinit) in order to affect GDB.
535 set python dont-write-bytecode auto|on|off
536 show python dont-write-bytecode
537 When 'on', this causes GDB's builtin Python to not write any
538 byte-code (.pyc files) to disk. This command needs to be added to
539 an early initialization file (e.g. ~/.config/gdb/gdbearlyinit) in
540 order to affect GDB. When 'off' byte-code will always be written.
541 When set to 'auto' (the default) Python will check the
542 PYTHONDONTWRITEBYTECODE environment variable.
546 break [PROBE_MODIFIER] [LOCATION] [thread THREADNUM]
547 [-force-condition] [if CONDITION]
548 This command would previously refuse setting a breakpoint if the
549 CONDITION expression is invalid at a location. It now accepts and
550 defines the breakpoint if there is at least one location at which
551 the CONDITION is valid. The locations for which the CONDITION is
552 invalid, are automatically disabled. If CONDITION is invalid at all
553 of the locations, setting the breakpoint is still rejected. However,
554 the '-force-condition' flag can be used in this case for forcing GDB to
555 define the breakpoint, making all the current locations automatically
556 disabled. This may be useful if the user knows the condition will
557 become meaningful at a future location, e.g. due to a shared library
560 condition [-force] N COND
561 The behavior of this command is changed the same way for the 'break'
562 command as explained above. The '-force' flag can be used to force
563 GDB into defining the condition even when COND is invalid for all the
564 current locations of breakpoint N.
567 maintenance flush-symbol-cache
568 These commands are deprecated in favor of the new commands
569 'maintenance flush register-cache' and 'maintenance flush
570 symbol-cache' respectively.
572 set style version foreground COLOR
573 set style version background COLOR
574 set style version intensity VALUE
575 Control the styling of GDB's version number text.
578 When the ID parameter is omitted, then this command prints information
579 about the current inferior. When the ID parameter is present, the
580 behavior of the command is unchanged and have the inferior ID become
581 the current inferior.
583 maintenance info sections
584 The ALLOBJ keyword has been replaced with an -all-objects command
585 line flag. It is now possible to filter which sections are printed
586 even when -all-objects is passed.
588 ptype[/FLAGS] TYPE | EXPRESSION
589 The 'ptype' command has two new flags. When '/x' is set, hexadecimal
590 notation is used when printing sizes and offsets of struct members.
591 When '/d' is set, decimal notation is used when printing sizes and
592 offsets of struct members. Default behavior is given by 'show print
596 The info sources command output has been restructured. The results
597 are now based around a list of objfiles (executable and libraries),
598 and for each objfile the source files that are part of that objfile
601 * Removed targets and native configurations
603 ARM Symbian arm*-*-symbianelf*
608 Request the remote to send allocation tags for a particular memory range.
610 Request the remote to store the specified allocation tags to the requested
615 ** Improved support for rvalue reference values:
616 TYPE_CODE_RVALUE_REF is now exported as part of the API and the
617 value-referenced-value procedure now handles rvalue reference
620 ** New procedures for obtaining value variants:
621 value-reference-value, value-rvalue-reference-value and
624 ** Temporary breakpoints can now be created with make-breakpoint and
625 tested for using breakpoint-temporary?.
629 ** Inferior objects now contain a read-only 'connection_num' attribute that
630 gives the connection number as seen in 'info connections' and
633 ** New method gdb.Frame.level() which returns the stack level of the
636 ** New method gdb.PendingFrame.level() which returns the stack level
639 ** When hitting a catchpoint, the Python API will now emit a
640 gdb.BreakpointEvent rather than a gdb.StopEvent. The
641 gdb.Breakpoint attached to the event will have type BP_CATCHPOINT.
643 ** Python TUI windows can now receive mouse click events. If the
644 Window object implements the click method, it is called for each
645 mouse click event in this window.
647 *** Changes in GDB 10
649 * There are new feature names for ARC targets: "org.gnu.gdb.arc.core"
650 and "org.gnu.gdb.arc.aux". The old names are still supported but
651 must be considered obsolete. They will be deprecated after some
654 * Help and apropos commands will now show the documentation of a
655 command only once, even if that command has one or more aliases.
656 These commands now show the command name, then all of its aliases,
657 and finally the description of the command.
659 * 'help aliases' now shows only the user defined aliases. GDB predefined
660 aliases are shown together with their aliased command.
662 * GDB now supports debuginfod, an HTTP server for distributing ELF/DWARF
663 debugging information as well as source code.
665 When built with debuginfod, GDB can automatically query debuginfod
666 servers for the separate debug files and source code of the executable
669 To build GDB with debuginfod, pass --with-debuginfod to configure (this
670 requires libdebuginfod, the debuginfod client library).
672 debuginfod is distributed with elfutils, starting with version 0.178.
674 You can get the latest version from https://sourceware.org/elfutils.
676 * Multi-target debugging support
678 GDB now supports debugging multiple target connections
679 simultaneously. For example, you can now have each inferior
680 connected to different remote servers running in different machines,
681 or have one inferior debugging a local native process, an inferior
682 debugging a core dump, etc.
684 This support is experimental and comes with some limitations -- you
685 can only resume multiple targets simultaneously if all targets
686 support non-stop mode, and all remote stubs or servers must support
687 the same set of remote protocol features exactly. See also "info
688 connections" and "add-inferior -no-connection" below, and "maint set
689 target-non-stop" in the user manual.
691 * New features in the GDB remote stub, GDBserver
693 ** GDBserver is now supported on ARC GNU/Linux.
695 ** GDBserver is now supported on RISC-V GNU/Linux.
697 ** GDBserver is now supported on LoongArch GNU/Linux.
699 ** GDBserver no longer supports these host triplets:
710 i[34567]86-*-mingw32ce*
712 * Debugging MS-Windows processes now sets $_exitsignal when the
713 inferior is terminated by a signal, instead of setting $_exitcode.
715 * Multithreaded symbol loading has now been enabled by default on systems
716 that support it (see entry for GDB 9, below), providing faster
717 performance for programs with many symbols.
719 * The $_siginfo convenience variable now also works on Windows targets,
720 and will display the EXCEPTION_RECORD of the last handled exception.
722 * TUI windows can now be arranged horizontally.
724 * The command history filename can now be set to the empty string
725 either using 'set history filename' or by setting 'GDBHISTFILE=' in
726 the environment. The effect of setting this filename to the empty
727 string is that GDB will not try to load any previous command
730 * On Windows targets, it is now possible to debug 32-bit programs with a
735 set exec-file-mismatch -- Set exec-file-mismatch handling (ask|warn|off).
736 show exec-file-mismatch -- Show exec-file-mismatch handling (ask|warn|off).
737 Set or show the option 'exec-file-mismatch'. When GDB attaches to a
738 running process, this new option indicates whether to detect
739 a mismatch between the current executable file loaded by GDB and the
740 executable file used to start the process. If 'ask', the default,
741 display a warning and ask the user whether to load the process
742 executable file; if 'warn', just display a warning; if 'off', don't
743 attempt to detect a mismatch.
745 tui new-layout NAME WINDOW WEIGHT [WINDOW WEIGHT]...
746 Define a new TUI layout, specifying its name and the windows that
749 maintenance print xml-tdesc [FILE]
750 Prints the current target description as an XML document. If the
751 optional FILE is provided (which is an XML target description) then
752 the target description is read from FILE into GDB, and then
755 maintenance print core-file-backed-mappings
756 Prints file-backed mappings loaded from a core file's note section.
757 Output is expected to be similar to that of "info proc mappings".
759 set debug fortran-array-slicing on|off
760 show debug fortran-array-slicing
761 Print debugging when taking slices of Fortran arrays.
763 set fortran repack-array-slices on|off
764 show fortran repack-array-slices
765 When taking slices from Fortran arrays and strings, if the slice is
766 non-contiguous within the original value then, when this option is
767 on, the new value will be repacked into a single contiguous value.
768 When this option is off, then the value returned will consist of a
769 descriptor that describes the slice within the memory of the
770 original parent value.
774 alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
775 The alias command can now specify default args for an alias.
776 GDB automatically prepends the alias default args to the argument list
777 provided explicitly by the user.
778 For example, to have a backtrace with full details, you can define
780 'alias bt_ALL = backtrace -entry-values both -frame-arg all
781 -past-main -past-entry -full'.
782 Alias default arguments can also use a set of nested 'with' commands,
783 e.g. 'alias pp10 = with print pretty -- with print elem 10 -- print'
784 defines the alias pp10 that will pretty print a maximum of 10 elements
785 of the given expression (if the expression is an array).
789 GNU/Linux/RISC-V (gdbserver) riscv*-*-linux*
790 GNU/Linux/LoongArch (gdbserver) loongarch*-*-linux*
796 ** gdb.register_window_type can be used to implement new TUI windows
799 ** Dynamic types can now be queried. gdb.Type has a new attribute,
800 "dynamic", and gdb.Type.sizeof can be None for a dynamic type. A
801 field of a dynamic type may have None for its "bitpos" attribute
804 ** Commands written in Python can be in the "TUI" help class by
805 registering with the new constant gdb.COMMAND_TUI.
807 ** New method gdb.PendingFrame.architecture () to retrieve the
808 architecture of the pending frame.
810 ** New gdb.Architecture.registers method that returns a
811 gdb.RegisterDescriptorIterator object, an iterator that returns
812 gdb.RegisterDescriptor objects. The new RegisterDescriptor is a
813 way to query the registers available for an architecture.
815 ** New gdb.Architecture.register_groups method that returns a
816 gdb.RegisterGroupIterator object, an iterator that returns
817 gdb.RegisterGroup objects. The new RegisterGroup is a way to
818 discover the available register groups.
822 ** GDB can now be built with GNU Guile 3.0 and 2.2 in addition to 2.0.
824 ** Procedures 'memory-port-read-buffer-size',
825 'set-memory-port-read-buffer-size!', 'memory-port-write-buffer-size',
826 and 'set-memory-port-write-buffer-size!' are deprecated. When
827 using Guile 2.2 and later, users who need to control the size of
828 a memory port's internal buffer can use the 'setvbuf' procedure.
832 * 'thread-exited' event is now available in the annotations interface.
834 * New built-in convenience variables $_gdb_major and $_gdb_minor
835 provide the GDB version. They are handy for conditionally using
836 features available only in or since specific GDB versions, in
837 scripts that should work error-free with many different versions,
838 such as in system-wide init files.
840 * New built-in convenience functions $_gdb_setting, $_gdb_setting_str,
841 $_gdb_maint_setting and $_gdb_maint_setting_str provide access to values
842 of the GDB settings and the GDB maintenance settings. They are handy
843 for changing the logic of user defined commands depending on the
844 current GDB settings.
846 * GDB now supports Thread Local Storage (TLS) variables on several
847 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
848 architectures require kernel changes. TLS is not yet supported for
849 amd64 and i386 process core dumps.
851 * Support for Pointer Authentication (PAC) on AArch64 Linux. Return
852 addresses that required unmasking are shown in the backtrace with the
855 * Two new convenience functions $_cimag and $_creal that extract the
856 imaginary and real parts respectively from complex numbers.
858 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
859 provide the exitcode or exit status of the shell commands launched by
860 GDB commands such as "shell", "pipe" and "make".
862 * The command define-prefix can now define user defined prefix commands.
863 User defined commands can now be defined using these user defined prefix
866 * Command names can now use the . character.
868 * The RX port now supports XML target descriptions.
870 * GDB now shows the Ada task names at more places, e.g. in task switching
873 * GDB can now be compiled with Python 3 on Windows.
875 * New convenience variable $_ada_exception holds the address of the
876 Ada exception being thrown. This is set by Ada-related catchpoints.
878 * GDB can now place breakpoints on nested functions and subroutines in
879 Fortran code. The '::' operator can be used between parent and
880 child scopes when placing breakpoints, for example:
882 (gdb) break outer_function::inner_function
884 The 'outer_function::' prefix is only needed if 'inner_function' is
885 not visible in the current scope.
887 * In addition to the system-wide gdbinit file, if configured with
888 --with-system-gdbinit-dir, GDB will now also load files in that directory
889 as system gdbinit files, unless the -nx or -n flag is provided. Files
890 with extensions .gdb, .py and .scm are supported as long as GDB was
891 compiled with support for that language.
893 * GDB now supports multithreaded symbol loading for higher performance.
894 This feature is still in testing, so it is disabled by default. You
895 can turn it on using 'maint set worker-threads unlimited'.
899 ** The gdb.Value type has a new method 'format_string' which returns a
900 string representing the value. The formatting is controlled by the
901 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
902 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
903 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
905 ** gdb.Type has a new property 'objfile' which returns the objfile the
908 ** The frame information printed by the python frame filtering code
909 is now consistent with what the 'backtrace' command prints when
910 there are no filters, or when the 'backtrace' '-no-filters' option
913 ** The new function gdb.lookup_static_symbol can be used to look up
914 symbols with static linkage.
916 ** The new function gdb.lookup_static_symbols can be used to look up
917 all static symbols with static linkage.
919 ** gdb.Objfile has new methods 'lookup_global_symbol' and
920 'lookup_static_symbol' to lookup a symbol from this objfile only.
922 ** gdb.Block now supports the dictionary syntax for accessing symbols in
923 this block (e.g. block['local_variable']).
927 | [COMMAND] | SHELL_COMMAND
928 | -d DELIM COMMAND DELIM SHELL_COMMAND
929 pipe [COMMAND] | SHELL_COMMAND
930 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
931 Executes COMMAND and sends its output to SHELL_COMMAND.
932 With no COMMAND, repeat the last executed command
933 and send its output to SHELL_COMMAND.
935 define-prefix COMMAND
936 Define or mark a command as a user-defined prefix command.
938 with SETTING [VALUE] [-- COMMAND]
939 w SETTING [VALUE] [-- COMMAND]
940 Temporarily set SETTING, run COMMAND, and restore SETTING.
941 Usage: with SETTING -- COMMAND
942 With no COMMAND, repeats the last executed command.
943 SETTING is any GDB setting you can change with the "set"
944 subcommands. For example, 'with language c -- print someobj'
945 temporarily switches to the C language in order to print someobj.
946 Settings can be combined: 'w lang c -- w print elements unlimited --
947 usercmd' switches to the C language and runs usercmd with no limit
948 of array elements to print.
950 maint with SETTING [VALUE] [-- COMMAND]
951 Like "with", but works with "maintenance set" settings.
953 set may-call-functions [on|off]
954 show may-call-functions
955 This controls whether GDB will attempt to call functions in
956 the program, such as with expressions in the print command. It
957 defaults to on. Calling functions in the program being debugged
958 can have undesired side effects. It is now possible to forbid
959 such function calls. If function calls are forbidden, GDB will throw
960 an error when a command (such as print expression) calls a function
963 set print finish [on|off]
965 This controls whether the `finish' command will display the value
966 that is returned by the current function. When `off', the value is
967 still entered into the value history, but it is not printed. The
972 Allows deeply nested structures to be simplified when printing by
973 replacing deeply nested parts (beyond the max-depth) with ellipses.
974 The default max-depth is 20, but this can be set to unlimited to get
975 the old behavior back.
977 set print raw-values [on|off]
978 show print raw-values
979 By default, GDB applies the enabled pretty printers when printing a
980 value. This allows to ignore the enabled pretty printers for a series
981 of commands. The default is 'off'.
983 set logging debugredirect [on|off]
984 By default, GDB debug output will go to both the terminal and the logfile.
985 Set if you want debug output to go only to the log file.
987 set style title foreground COLOR
988 set style title background COLOR
989 set style title intensity VALUE
990 Control the styling of titles.
992 set style highlight foreground COLOR
993 set style highlight background COLOR
994 set style highlight intensity VALUE
995 Control the styling of highlightings.
997 maint set worker-threads
998 maint show worker-threads
999 Control the number of worker threads that can be used by GDB. The
1000 default is 0. "unlimited" lets GDB choose a number that is
1001 reasonable. Currently worker threads are only used when demangling
1002 the names of linker symbols.
1004 set style tui-border foreground COLOR
1005 set style tui-border background COLOR
1006 Control the styling of TUI borders.
1008 set style tui-active-border foreground COLOR
1009 set style tui-active-border background COLOR
1010 Control the styling of the active TUI border.
1012 maint set test-settings KIND
1013 maint show test-settings KIND
1014 A set of commands used by the testsuite for exercising the settings
1017 maint set tui-resize-message [on|off]
1018 maint show tui-resize-message
1019 Control whether GDB prints a message each time the terminal is
1020 resized when in TUI mode. This is primarily useful for testing the
1023 set print frame-info [short-location|location|location-and-address
1024 |source-and-location|source-line|auto]
1025 show print frame-info
1026 This controls what frame information is printed by the commands printing
1027 a frame. This setting will e.g. influence the behaviour of 'backtrace',
1028 'frame', 'stepi'. The python frame filtering also respect this setting.
1029 The 'backtrace' '-frame-info' option can override this global setting.
1031 set tui compact-source
1032 show tui compact-source
1034 Enable the "compact" display mode for the TUI source window. The
1035 compact display uses only as much space as is needed for the line
1036 numbers in the current file, and only a single space to separate the
1037 line numbers from the source.
1039 info modules [-q] [REGEXP]
1040 Return a list of Fortran modules matching REGEXP, or all modules if
1043 info module functions [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
1044 Return a list of functions within all modules, grouped by module.
1045 The list of functions can be restricted with the optional regular
1046 expressions. MODULE_REGEXP matches against the module name,
1047 TYPE_REGEXP matches against the function type signature, and REGEXP
1048 matches against the function name.
1050 info module variables [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
1051 Return a list of variables within all modules, grouped by module.
1052 The list of variables can be restricted with the optional regular
1053 expressions. MODULE_REGEXP matches against the module name,
1054 TYPE_REGEXP matches against the variable type, and REGEXP matches
1055 against the variable name.
1057 set debug remote-packet-max-chars
1058 show debug remote-packet-max-chars
1059 Controls the number of characters to output in a remote packet when using
1061 The default is 512 bytes.
1064 Lists the target connections currently in use.
1069 The "help" command uses the title style to enhance the
1070 readibility of its output by styling the classes and
1074 Similarly to "help", the "apropos" command also uses the
1075 title style for the command names. "apropos" accepts now
1076 a flag "-v" (verbose) to show the full documentation
1077 of matching commands and to use the highlight style to mark
1078 the documentation parts matching REGEXP.
1082 The GDB printf and eval commands can now print C-style and Ada-style
1083 string convenience variables without calling functions in the program.
1084 This allows to do formatted printing of strings without having
1085 a running inferior, or when debugging a core dump.
1087 info sources [-dirname | -basename] [--] [REGEXP]
1088 This command has now optional arguments to only print the files
1089 whose names match REGEXP. The arguments -dirname and -basename
1090 allow to restrict matching respectively to the dirname and basename
1094 The "show style" and its subcommands are now styling
1095 a style name in their output using its own style, to help
1096 the user visualize the different styles.
1098 set print frame-arguments
1099 The new value 'presence' indicates to only indicate the presence of
1100 arguments using ..., instead of printing argument names and values.
1102 set print raw-frame-arguments
1103 show print raw-frame-arguments
1105 These commands replace the similarly-named "set/show print raw
1106 frame-arguments" commands (now with a dash instead of a space). The
1107 old commands are now deprecated and may be removed in a future
1110 add-inferior [-no-connection]
1111 The add-inferior command now supports a "-no-connection" flag that
1112 makes the new inferior start with no target connection associated.
1113 By default, the new inferior inherits the target connection of the
1114 current inferior. See also "info connections".
1117 This command's output now includes a new "Connection" column
1118 indicating which target connection an inferior is bound to. See
1119 "info connections" above.
1121 maint test-options require-delimiter
1122 maint test-options unknown-is-error
1123 maint test-options unknown-is-operand
1124 maint show test-options-completion-result
1125 Commands used by the testsuite to validate the command options
1128 focus, winheight, +, -, >, <
1129 These commands are now case-sensitive.
1131 * New command options, command completion
1133 GDB now has a standard infrastructure to support dash-style command
1134 options ('-OPT'). One benefit is that commands that use it can
1135 easily support completion of command line arguments. Try "CMD
1136 -[TAB]" or "help CMD" to find options supported by a command. Over
1137 time, we intend to migrate most commands to this infrastructure. A
1138 number of commands got support for new command options in this
1141 ** The "print" and "compile print" commands now support a number of
1142 options that allow overriding relevant global print settings as
1143 set by "set print" subcommands:
1147 -array-indexes [on|off]
1148 -elements NUMBER|unlimited
1152 -raw-values [on|off]
1153 -repeats NUMBER|unlimited
1154 -static-members [on|off]
1159 Note that because the "print"/"compile print" commands accept
1160 arbitrary expressions which may look like options (including
1161 abbreviations), if you specify any command option, then you must
1162 use a double dash ("--") to mark the end of argument processing.
1164 ** The "backtrace" command now supports a number of options that
1165 allow overriding relevant global print settings as set by "set
1166 backtrace" and "set print" subcommands:
1168 -entry-values no|only|preferred|if-needed|both|compact|default
1169 -frame-arguments all|scalars|none
1170 -raw-frame-arguments [on|off]
1171 -frame-info auto|source-line|location|source-and-location
1172 |location-and-address|short-location
1174 -past-entry [on|off]
1176 In addition, the full/no-filters/hide qualifiers are now also
1177 exposed as command options too:
1183 ** The "frame apply", "tfaas" and "faas" commands similarly now
1184 support the following options:
1187 -past-entry [on|off]
1189 ** The new "info sources" options -dirname and -basename options
1190 are using the standard '-OPT' infrastructure.
1192 All options above can also be abbreviated. The argument of boolean
1193 (on/off) options can be 0/1 too, and also the argument is assumed
1194 "on" if omitted. This allows writing compact command invocations,
1197 (gdb) p -ra -p -o 0 -- *myptr
1199 The above is equivalent to:
1201 (gdb) print -raw-values -pretty -object off -- *myptr
1203 ** The "info types" command now supports the '-q' flag to disable
1204 printing of some header information in a similar fashion to "info
1205 variables" and "info functions".
1207 ** The "info variables", "info functions", and "whereis" commands
1208 now take a '-n' flag that excludes non-debug symbols (symbols
1209 from the symbol table, not from the debug info such as DWARF)
1212 * Completion improvements
1214 ** GDB can now complete the options of the "thread apply all" and
1215 "taas" commands, and their "-ascending" option can now be
1218 ** GDB can now complete the options of the "info threads", "info
1219 functions", "info variables", "info locals", and "info args"
1222 ** GDB can now complete the options of the "compile file" and
1223 "compile code" commands. The "compile file" command now
1224 completes on filenames.
1226 ** GDB can now complete the backtrace command's
1227 "full/no-filters/hide" qualifiers.
1229 * In settings, you can now abbreviate "unlimited".
1231 E.g., "set print elements u" is now equivalent to "set print
1232 elements unlimited".
1237 This lists all the possible completions for the rest of the line, if it
1238 were to be given as a command itself. This is intended for use by MI
1239 frontends in cases when separate CLI and MI channels cannot be used.
1241 -catch-throw, -catch-rethrow, and -catch-catch
1242 These can be used to catch C++ exceptions in a similar fashion to
1243 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
1245 -symbol-info-functions, -symbol-info-types, and -symbol-info-variables
1246 These commands are the MI equivalent of the CLI commands 'info
1247 functions', 'info types', and 'info variables' respectively.
1249 -symbol-info-modules, this is the MI equivalent of the CLI 'info
1252 -symbol-info-module-functions and -symbol-info-module-variables.
1253 These commands are the MI equivalent of the CLI commands 'info
1254 module functions' and 'info module variables'.
1258 ** The default version of the MI interpreter is now 3 (-i=mi3).
1260 ** The output of information about multi-location breakpoints (which is
1261 syntactically incorrect in MI 2) has changed in MI 3. This affects
1262 the following commands and events:
1266 - =breakpoint-created
1267 - =breakpoint-modified
1269 The -fix-multi-location-breakpoint-output command can be used to enable
1270 this behavior with previous MI versions.
1272 ** Backtraces and frames include a new optional field addr_flags which is
1273 given after the addr field. On AArch64 this contains PAC if the address
1274 has been masked in the frame. On all other targets the field is not
1279 The testsuite now creates the files gdb.cmd (containing the arguments
1280 used to launch GDB) and gdb.in (containing all the commands sent to
1281 GDB) in the output directory for each test script. Multiple invocations
1282 are appended with .1, .2, .3 etc.
1284 * Building GDB and GDBserver now requires GNU make >= 3.82.
1286 Using another implementation of the make program or an earlier version of
1287 GNU make to build GDB or GDBserver is not supported.
1289 * Building GDB now requires GNU readline >= 7.0.
1291 GDB now bundles GNU readline 8.0, but if you choose to use
1292 --with-system-readline, only readline >= 7.0 can be used.
1294 * The TUI SingleKey keymap is now named "SingleKey". This can be used
1295 from .inputrc to bind keys in this keymap. This feature is only
1296 available when gdb is built against GNU readline 8.0 or later.
1298 * Removed targets and native configurations
1300 GDB no longer supports debugging the Cell Broadband Engine. This includes
1301 both debugging standalone Cell/B.E. SPU applications and integrated debugging
1302 of Cell/B.E. applications that use both the PPU and SPU architectures.
1308 * Removed targets and native configurations
1310 Solaris 10 i?86-*-solaris2.10, x86_64-*-solaris2.10,
1311 sparc*-*-solaris2.10
1313 *** Changes in GDB 8.3
1315 * GDB and GDBserver now support access to additional registers on
1316 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
1319 * GDB now has experimental support for the compilation and injection of
1320 C++ source code into the inferior. This beta release does not include
1321 support for several language features, such as templates, constructors,
1324 This feature requires GCC 7.1 or higher built with libcp1.so
1327 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
1328 can be passed using the '[ADDRESS]:PORT' notation, or the regular
1329 'ADDRESS:PORT' method.
1331 * DWARF index cache: GDB can now automatically save indices of DWARF
1332 symbols on disk to speed up further loading of the same binaries.
1334 * Ada task switching is now supported on aarch64-elf targets when
1335 debugging a program using the Ravenscar Profile. For more information,
1336 see the "Tasking Support when using the Ravenscar Profile" section
1337 in the GDB user manual.
1339 * GDB in batch mode now exits with status 1 if the last command to be
1342 * The RISC-V target now supports target descriptions.
1344 * System call catchpoints now support system call aliases on FreeBSD.
1345 When the ABI of a system call changes in FreeBSD, this is
1346 implemented by leaving a compatibility system call using the old ABI
1347 at the existing number and allocating a new system call number for
1348 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
1349 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
1350 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
1351 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
1352 so that a system call catchpoint for the 'kevent' system call will
1353 catch invocations of both the 'kevent' and 'freebsd11_kevent'
1354 binaries. This ensures that 'kevent' system calls are caught for
1355 binaries using either the old or new ABIs.
1357 * Terminal styling is now available for the CLI and the TUI. GNU
1358 Source Highlight can additionally be used to provide styling of
1359 source code snippets. See the "set style" commands, below, for more
1362 * Removed support for old demangling styles arm, edg, gnu, hp and
1367 set debug compile-cplus-types
1368 show debug compile-cplus-types
1369 Control the display of debug output about type conversion in the
1370 C++ compile feature. Commands have no effect while compiling
1371 for other languages.
1375 Control whether debug output about files/functions skipping is
1378 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
1379 Apply a command to some frames.
1380 FLAG arguments allow to control what output to produce and how to handle
1381 errors raised when applying COMMAND to a frame.
1384 Apply a command to all threads (ignoring errors and empty output).
1385 Shortcut for 'thread apply all -s COMMAND'.
1388 Apply a command to all frames (ignoring errors and empty output).
1389 Shortcut for 'frame apply all -s COMMAND'.
1392 Apply a command to all frames of all threads (ignoring errors and empty
1394 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
1396 maint set dwarf unwinders (on|off)
1397 maint show dwarf unwinders
1398 Control whether DWARF unwinders can be used.
1401 Display a list of open files for a process.
1405 Changes to the "frame", "select-frame", and "info frame" CLI commands.
1406 These commands all now take a frame specification which
1407 is either a frame level, or one of the keywords 'level', 'address',
1408 'function', or 'view' followed by a parameter. Selecting a frame by
1409 address, or viewing a frame outside the current backtrace now
1410 requires the use of a keyword. Selecting a frame by level is
1411 unchanged. The MI comment "-stack-select-frame" is unchanged.
1413 target remote FILENAME
1414 target extended-remote FILENAME
1415 If FILENAME is a Unix domain socket, GDB will attempt to connect
1416 to this socket instead of opening FILENAME as a character device.
1418 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
1419 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
1420 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
1421 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
1422 These commands can now print only the searched entities
1423 matching the provided regexp(s), giving a condition
1424 on the entity names or entity types. The flag -q disables
1425 printing headers or informations messages.
1431 These commands now determine the syntax for the shown entities
1432 according to the language chosen by `set language'. In particular,
1433 `set language auto' means to automatically choose the language of
1436 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
1437 The 'thread apply' command accepts new FLAG arguments.
1438 FLAG arguments allow to control what output to produce and how to handle
1439 errors raised when applying COMMAND to a thread.
1441 set tui tab-width NCHARS
1442 show tui tab-width NCHARS
1443 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
1445 set style enabled [on|off]
1447 Enable or disable terminal styling. Styling is enabled by default
1448 on most hosts, but disabled by default when in batch mode.
1450 set style sources [on|off]
1452 Enable or disable source code styling. Source code styling is
1453 enabled by default, but only takes effect if styling in general is
1454 enabled, and if GDB was linked with GNU Source Highlight.
1456 set style filename foreground COLOR
1457 set style filename background COLOR
1458 set style filename intensity VALUE
1459 Control the styling of file names.
1461 set style function foreground COLOR
1462 set style function background COLOR
1463 set style function intensity VALUE
1464 Control the styling of function names.
1466 set style variable foreground COLOR
1467 set style variable background COLOR
1468 set style variable intensity VALUE
1469 Control the styling of variable names.
1471 set style address foreground COLOR
1472 set style address background COLOR
1473 set style address intensity VALUE
1474 Control the styling of addresses.
1478 ** The '-data-disassemble' MI command now accepts an '-a' option to
1479 disassemble the whole function surrounding the given program
1480 counter value or function name. Support for this feature can be
1481 verified by using the "-list-features" command, which should
1482 contain "data-disassemble-a-option".
1484 ** Command responses and notifications that include a frame now include
1485 the frame's architecture in a new "arch" attribute.
1487 * New native configurations
1489 GNU/Linux/RISC-V riscv*-*-linux*
1490 FreeBSD/riscv riscv*-*-freebsd*
1494 GNU/Linux/RISC-V riscv*-*-linux*
1495 CSKY ELF csky*-*-elf
1496 CSKY GNU/LINUX csky*-*-linux
1497 FreeBSD/riscv riscv*-*-freebsd*
1499 GNU/Linux/OpenRISC or1k*-*-linux*
1503 GDB no longer supports native debugging on versions of MS-Windows
1508 ** GDB no longer supports Python versions less than 2.6.
1510 ** The gdb.Inferior type has a new 'progspace' property, which is the program
1511 space associated to that inferior.
1513 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
1514 of objfiles associated to that program space.
1516 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
1517 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
1520 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
1521 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
1522 correct and did not work properly.
1524 ** The gdb.Value type has a new constructor, which is used to construct a
1525 gdb.Value from a Python buffer object and a gdb.Type.
1531 Enable or disable the undefined behavior sanitizer. This is
1532 disabled by default, but passing --enable-ubsan=yes or
1533 --enable-ubsan=auto to configure will enable it. Enabling this can
1534 cause a performance penalty. The undefined behavior sanitizer was
1535 first introduced in GCC 4.9.
1537 *** Changes in GDB 8.2
1539 * The 'set disassembler-options' command now supports specifying options
1540 for the MIPS target.
1542 * The 'symbol-file' command now accepts an '-o' option to add a relative
1543 offset to all sections.
1545 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
1546 a relative offset to all sections, but it allows to override the load
1547 address of individual sections using '-s'.
1549 * The 'add-symbol-file' command no longer requires the second argument
1550 (address of the text section).
1552 * The endianness used with the 'set endian auto' mode in the absence of
1553 an executable selected for debugging is now the last endianness chosen
1554 either by one of the 'set endian big' and 'set endian little' commands
1555 or by inferring from the last executable used, rather than the startup
1558 * The pager now allows a "c" response, meaning to disable the pager
1559 for the rest of the current command.
1561 * The commands 'info variables/functions/types' now show the source line
1562 numbers of symbol definitions when available.
1564 * 'info proc' now works on running processes on FreeBSD systems and core
1565 files created on FreeBSD systems.
1567 * C expressions can now use _Alignof, and C++ expressions can now use
1570 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
1571 the vector length while the process is running.
1577 Control display of debugging info regarding the FreeBSD native target.
1579 set|show varsize-limit
1580 This new setting allows the user to control the maximum size of Ada
1581 objects being printed when those objects have a variable type,
1582 instead of that maximum size being hardcoded to 65536 bytes.
1584 set|show record btrace cpu
1585 Controls the processor to be used for enabling errata workarounds for
1586 branch trace decode.
1588 maint check libthread-db
1589 Run integrity checks on the current inferior's thread debugging
1592 maint set check-libthread-db (on|off)
1593 maint show check-libthread-db
1594 Control whether to run integrity checks on inferior specific thread
1595 debugging libraries as they are loaded. The default is not to
1596 perform such checks.
1600 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
1602 ** The commands attached to a breakpoint can be set by assigning to
1603 the breakpoint's "commands" field.
1605 ** gdb.execute can now execute multi-line gdb commands.
1607 ** The new functions gdb.convenience_variable and
1608 gdb.set_convenience_variable can be used to get and set the value
1609 of convenience variables.
1611 ** A gdb.Parameter will no longer print the "set" help text on an
1612 ordinary "set"; instead by default a "set" will be silent unless
1613 the get_set_string method returns a non-empty string.
1617 RiscV ELF riscv*-*-elf
1619 * Removed targets and native configurations
1621 m88k running OpenBSD m88*-*-openbsd*
1622 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
1623 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
1624 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
1626 * Aarch64/Linux hardware watchpoints improvements
1628 Hardware watchpoints on unaligned addresses are now properly
1629 supported when running Linux kernel 4.10 or higher: read and access
1630 watchpoints are no longer spuriously missed, and all watchpoints
1631 lengths between 1 and 8 bytes are supported. On older kernels,
1632 watchpoints set on unaligned addresses are no longer missed, with
1633 the tradeoff that there is a possibility of false hits being
1638 --enable-codesign=CERT
1639 This can be used to invoke "codesign -s CERT" after building gdb.
1640 This option is useful on macOS, where code signing is required for
1641 gdb to work properly.
1643 --disable-gdbcli has been removed
1644 This is now silently accepted, but does nothing.
1646 *** Changes in GDB 8.1
1648 * GDB now supports dynamically creating arbitrary register groups specified
1649 in XML target descriptions. This allows for finer grain grouping of
1650 registers on systems with a large amount of registers.
1652 * The 'ptype' command now accepts a '/o' flag, which prints the
1653 offsets and sizes of fields in a struct, like the pahole(1) tool.
1655 * New "--readnever" command line option instructs GDB to not read each
1656 symbol file's symbolic debug information. This makes startup faster
1657 but at the expense of not being able to perform symbolic debugging.
1658 This option is intended for use cases where symbolic debugging will
1659 not be used, e.g., when you only need to dump the debuggee's core.
1661 * GDB now uses the GNU MPFR library, if available, to emulate target
1662 floating-point arithmetic during expression evaluation when the target
1663 uses different floating-point formats than the host. At least version
1664 3.1 of GNU MPFR is required.
1666 * GDB now supports access to the guarded-storage-control registers and the
1667 software-based guarded-storage broadcast control registers on IBM z14.
1669 * On Unix systems, GDB now supports transmitting environment variables
1670 that are to be set or unset to GDBserver. These variables will
1671 affect the environment to be passed to the remote inferior.
1673 To inform GDB of environment variables that are to be transmitted to
1674 GDBserver, use the "set environment" command. Only user set
1675 environment variables are sent to GDBserver.
1677 To inform GDB of environment variables that are to be unset before
1678 the remote inferior is started by the GDBserver, use the "unset
1679 environment" command.
1681 * Completion improvements
1683 ** GDB can now complete function parameters in linespecs and
1684 explicit locations without quoting. When setting breakpoints,
1685 quoting around functions names to help with TAB-completion is
1686 generally no longer necessary. For example, this now completes
1689 (gdb) b function(in[TAB]
1690 (gdb) b function(int)
1692 Related, GDB is no longer confused with completing functions in
1693 C++ anonymous namespaces:
1696 (gdb) b (anonymous namespace)::[TAB][TAB]
1697 (anonymous namespace)::a_function()
1698 (anonymous namespace)::b_function()
1700 ** GDB now has much improved linespec and explicit locations TAB
1701 completion support, that better understands what you're
1702 completing and offers better suggestions. For example, GDB no
1703 longer offers data symbols as possible completions when you're
1704 setting a breakpoint.
1706 ** GDB now TAB-completes label symbol names.
1708 ** The "complete" command now mimics TAB completion accurately.
1710 * New command line options (gcore)
1713 Dump all memory mappings.
1715 * Breakpoints on C++ functions are now set on all scopes by default
1717 By default, breakpoints on functions/methods are now interpreted as
1718 specifying all functions with the given name ignoring missing
1719 leading scopes (namespaces and classes).
1721 For example, assuming a C++ program with symbols named:
1726 both commands "break func()" and "break B::func()" set a breakpoint
1729 You can use the new flag "-qualified" to override this. This makes
1730 GDB interpret the specified function name as a complete
1731 fully-qualified name instead. For example, using the same C++
1732 program, the "break -q B::func" command sets a breakpoint on
1733 "B::func", only. A parameter has been added to the Python
1734 gdb.Breakpoint constructor to achieve the same result when creating
1735 a breakpoint from Python.
1737 * Breakpoints on functions marked with C++ ABI tags
1739 GDB can now set breakpoints on functions marked with C++ ABI tags
1740 (e.g., [abi:cxx11]). See here for a description of ABI tags:
1741 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
1743 Functions with a C++11 abi tag are demangled/displayed like this:
1745 function[abi:cxx11](int)
1748 You can now set a breakpoint on such functions simply as if they had
1751 (gdb) b function(int)
1753 Or if you need to disambiguate between tags, like:
1755 (gdb) b function[abi:other_tag](int)
1757 Tab completion was adjusted accordingly as well.
1761 ** New events gdb.new_inferior, gdb.inferior_deleted, and
1762 gdb.new_thread are emitted. See the manual for further
1763 description of these.
1765 ** A new function, "gdb.rbreak" has been added to the Python API.
1766 This function allows the setting of a large number of breakpoints
1767 via a regex pattern in Python. See the manual for further details.
1769 ** Python breakpoints can now accept explicit locations. See the
1770 manual for a further description of this feature.
1773 * New features in the GDB remote stub, GDBserver
1775 ** GDBserver is now able to start inferior processes with a
1776 specified initial working directory.
1778 The user can set the desired working directory to be used from
1779 GDB using the new "set cwd" command.
1781 ** New "--selftest" command line option runs some GDBserver self
1782 tests. These self tests are disabled in releases.
1784 ** On Unix systems, GDBserver now does globbing expansion and variable
1785 substitution in inferior command line arguments.
1787 This is done by starting inferiors using a shell, like GDB does.
1788 See "set startup-with-shell" in the user manual for how to disable
1789 this from GDB when using "target extended-remote". When using
1790 "target remote", you can disable the startup with shell by using the
1791 new "--no-startup-with-shell" GDBserver command line option.
1793 ** On Unix systems, GDBserver now supports receiving environment
1794 variables that are to be set or unset from GDB. These variables
1795 will affect the environment to be passed to the inferior.
1797 * When catching an Ada exception raised with a message, GDB now prints
1798 the message in the catchpoint hit notification. In GDB/MI mode, that
1799 information is provided as an extra field named "exception-message"
1800 in the *stopped notification.
1802 * Trait objects can now be inspected When debugging Rust code. This
1803 requires compiler support which will appear in Rust 1.24.
1805 * New remote packets
1807 QEnvironmentHexEncoded
1808 Inform GDBserver of an environment variable that is to be passed to
1809 the inferior when starting it.
1812 Inform GDBserver of an environment variable that is to be unset
1813 before starting the remote inferior.
1816 Inform GDBserver that the environment should be reset (i.e.,
1817 user-set environment variables should be unset).
1820 Indicates whether the inferior must be started with a shell or not.
1823 Tell GDBserver that the inferior to be started should use a specific
1826 * The "maintenance print c-tdesc" command now takes an optional
1827 argument which is the file name of XML target description.
1829 * The "maintenance selftest" command now takes an optional argument to
1830 filter the tests to be run.
1832 * The "enable", and "disable" commands now accept a range of
1833 breakpoint locations, e.g. "enable 1.3-5".
1838 Set and show the current working directory for the inferior.
1840 set|show compile-gcc
1841 Set and show compilation command used for compiling and injecting code
1842 with the 'compile' commands.
1844 set debug separate-debug-file
1845 show debug separate-debug-file
1846 Control the display of debug output about separate debug file search.
1848 set dump-excluded-mappings
1849 show dump-excluded-mappings
1850 Control whether mappings marked with the VM_DONTDUMP flag should be
1851 dumped when generating a core file.
1853 maint info selftests
1854 List the registered selftests.
1857 Start the debugged program stopping at the first instruction.
1860 Control display of debugging messages related to OpenRISC targets.
1862 set|show print type nested-type-limit
1863 Set and show the limit of nesting level for nested types that the
1864 type printer will show.
1866 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
1869 * Safer/improved support for debugging with no debug info
1871 GDB no longer assumes functions with no debug information return
1874 This means that GDB now refuses to call such functions unless you
1875 tell it the function's type, by either casting the call to the
1876 declared return type, or by casting the function to a function
1877 pointer of the right type, and calling that:
1879 (gdb) p getenv ("PATH")
1880 'getenv' has unknown return type; cast the call to its declared return type
1881 (gdb) p (char *) getenv ("PATH")
1882 $1 = 0x7fffffffe "/usr/local/bin:/"...
1883 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
1884 $2 = 0x7fffffffe "/usr/local/bin:/"...
1886 Similarly, GDB no longer assumes that global variables with no debug
1887 info have type 'int', and refuses to print the variable's value
1888 unless you tell it the variable's type:
1891 'var' has unknown type; cast it to its declared type
1895 * New native configurations
1897 FreeBSD/aarch64 aarch64*-*-freebsd*
1898 FreeBSD/arm arm*-*-freebsd*
1902 FreeBSD/aarch64 aarch64*-*-freebsd*
1903 FreeBSD/arm arm*-*-freebsd*
1904 OpenRISC ELF or1k*-*-elf
1906 * Removed targets and native configurations
1908 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
1910 *** Changes in GDB 8.0
1912 * GDB now supports access to the PKU register on GNU/Linux. The register is
1913 added by the Memory Protection Keys for Userspace feature which will be
1914 available in future Intel CPUs.
1916 * GDB now supports C++11 rvalue references.
1920 ** New functions to start, stop and access a running btrace recording.
1921 ** Rvalue references are now supported in gdb.Type.
1923 * GDB now supports recording and replaying rdrand and rdseed Intel 64
1926 * Building GDB and GDBserver now requires a C++11 compiler.
1928 For example, GCC 4.8 or later.
1930 It is no longer possible to build GDB or GDBserver with a C
1931 compiler. The --disable-build-with-cxx configure option has been
1934 * Building GDB and GDBserver now requires GNU make >= 3.81.
1936 It is no longer supported to build GDB or GDBserver with another
1937 implementation of the make program or an earlier version of GNU make.
1939 * Native debugging on MS-Windows supports command-line redirection
1941 Command-line arguments used for starting programs on MS-Windows can
1942 now include redirection symbols supported by native Windows shells,
1943 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
1944 as "run", "start", and "set args", as well as the corresponding MI
1947 * Support for thread names on MS-Windows.
1949 GDB now catches and handles the special exception that programs
1950 running on MS-Windows use to assign names to threads in the
1953 * Support for Java programs compiled with gcj has been removed.
1955 * User commands now accept an unlimited number of arguments.
1956 Previously, only up to 10 was accepted.
1958 * The "eval" command now expands user-defined command arguments.
1960 This makes it easier to process a variable number of arguments:
1965 eval "print $arg%d", $i
1970 * Target descriptions can now describe registers for sparc32 and sparc64.
1972 * GDB now supports DWARF version 5 (debug information format).
1973 Its .debug_names index is not yet supported.
1975 * New native configurations
1977 FreeBSD/mips mips*-*-freebsd
1981 Synopsys ARC arc*-*-elf32
1982 FreeBSD/mips mips*-*-freebsd
1984 * Removed targets and native configurations
1986 Alpha running FreeBSD alpha*-*-freebsd*
1987 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
1992 Erases all the flash memory regions reported by the target.
1994 maint print arc arc-instruction address
1995 Print internal disassembler information about instruction at a given address.
1999 set disassembler-options
2000 show disassembler-options
2001 Controls the passing of target specific information to the disassembler.
2002 If it is necessary to specify more than one disassembler option then
2003 multiple options can be placed together into a comma separated list.
2004 The default value is the empty string. Currently, the only supported
2005 targets are ARM, PowerPC and S/390.
2010 Erases all the flash memory regions reported by the target. This is
2011 equivalent to the CLI command flash-erase.
2013 -file-list-shared-libraries
2014 List the shared libraries in the program. This is
2015 equivalent to the CLI command "info shared".
2018 Catchpoints stopping the program when Ada exceptions are
2019 handled. This is equivalent to the CLI command "catch handlers".
2021 *** Changes in GDB 7.12
2023 * GDB and GDBserver now build with a C++ compiler by default.
2025 The --enable-build-with-cxx configure option is now enabled by
2026 default. One must now explicitly configure with
2027 --disable-build-with-cxx in order to build with a C compiler. This
2028 option will be removed in a future release.
2030 * GDBserver now supports recording btrace without maintaining an active
2033 * GDB now supports a negative repeat count in the 'x' command to examine
2034 memory backward from the given address. For example:
2037 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
2038 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
2039 (gdb) x/-5i 0x0000000000400580
2040 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
2041 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
2042 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
2043 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
2044 0x40057b <main(int, char**)+25>:
2045 callq 0x400536 <Func1(int, char const*)>
2047 * Fortran: Support structures with fields of dynamic types and
2048 arrays of dynamic types.
2050 * The symbol dumping maintenance commands have new syntax.
2051 maint print symbols [-pc address] [--] [filename]
2052 maint print symbols [-objfile objfile] [-source source] [--] [filename]
2053 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
2054 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
2055 maint print msymbols [-objfile objfile] [--] [filename]
2057 * GDB now supports multibit bitfields and enums in target register
2060 * New Python-based convenience function $_as_string(val), which returns
2061 the textual representation of a value. This function is especially
2062 useful to obtain the text label of an enum value.
2064 * Intel MPX bound violation handling.
2066 Segmentation faults caused by a Intel MPX boundary violation
2067 now display the kind of violation (upper or lower), the memory
2068 address accessed and the memory bounds, along with the usual
2069 signal received and code location.
2073 Program received signal SIGSEGV, Segmentation fault
2074 Upper bound violation while accessing address 0x7fffffffc3b3
2075 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
2076 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
2078 * Rust language support.
2079 GDB now supports debugging programs written in the Rust programming
2080 language. See https://www.rust-lang.org/ for more information about
2083 * Support for running interpreters on specified input/output devices
2085 GDB now supports a new mechanism that allows frontends to provide
2086 fully featured GDB console views, as a better alternative to
2087 building such views on top of the "-interpreter-exec console"
2088 command. See the new "new-ui" command below. With that command,
2089 frontends can now start GDB in the traditional command-line mode
2090 running in an embedded terminal emulator widget, and create a
2091 separate MI interpreter running on a specified i/o device. In this
2092 way, GDB handles line editing, history, tab completion, etc. in the
2093 console all by itself, and the GUI uses the separate MI interpreter
2094 for its own control and synchronization, invisible to the command
2097 * The "catch syscall" command catches groups of related syscalls.
2099 The "catch syscall" command now supports catching a group of related
2100 syscalls using the 'group:' or 'g:' prefix.
2105 skip -gfile file-glob-pattern
2106 skip -function function
2107 skip -rfunction regular-expression
2108 A generalized form of the skip command, with new support for
2109 glob-style file names and regular expressions for function names.
2110 Additionally, a file spec and a function spec may now be combined.
2112 maint info line-table REGEXP
2113 Display the contents of GDB's internal line table data structure.
2116 Run any GDB unit tests that were compiled in.
2119 Start a new user interface instance running INTERP as interpreter,
2120 using the TTY file for input/output.
2124 ** gdb.Breakpoint objects have a new attribute "pending", which
2125 indicates whether the breakpoint is pending.
2126 ** Three new breakpoint-related events have been added:
2127 gdb.breakpoint_created, gdb.breakpoint_modified, and
2128 gdb.breakpoint_deleted.
2130 signal-event EVENTID
2131 Signal ("set") the given MS-Windows event object. This is used in
2132 conjunction with the Windows JIT debugging (AeDebug) support, where
2133 the OS suspends a crashing process until a debugger can attach to
2134 it. Resuming the crashing process, in order to debug it, is done by
2135 signalling an event.
2137 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
2138 was added in GDBserver, including JIT compiling fast tracepoint's
2139 conditional expression bytecode into native code.
2141 * Support for various remote target protocols and ROM monitors has
2144 target m32rsdi Remote M32R debugging over SDI
2145 target mips MIPS remote debugging protocol
2146 target pmon PMON ROM monitor
2147 target ddb NEC's DDB variant of PMON for Vr4300
2148 target rockhopper NEC RockHopper variant of PMON
2149 target lsi LSI variant of PMO
2151 * Support for tracepoints and fast tracepoints on powerpc-linux,
2152 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
2153 including JIT compiling fast tracepoint's conditional expression
2154 bytecode into native code.
2156 * MI async record =record-started now includes the method and format used for
2157 recording. For example:
2159 =record-started,thread-group="i1",method="btrace",format="bts"
2161 * MI async record =thread-selected now includes the frame field. For example:
2163 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
2167 Andes NDS32 nds32*-*-elf
2169 *** Changes in GDB 7.11
2171 * GDB now supports debugging kernel-based threads on FreeBSD.
2173 * Per-inferior thread numbers
2175 Thread numbers are now per inferior instead of global. If you're
2176 debugging multiple inferiors, GDB displays thread IDs using a
2177 qualified INF_NUM.THR_NUM form. For example:
2181 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
2182 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
2183 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
2184 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
2186 As consequence, thread numbers as visible in the $_thread
2187 convenience variable and in Python's InferiorThread.num attribute
2188 are no longer unique between inferiors.
2190 GDB now maintains a second thread ID per thread, referred to as the
2191 global thread ID, which is the new equivalent of thread numbers in
2192 previous releases. See also $_gthread below.
2194 For backwards compatibility, MI's thread IDs always refer to global
2197 * Commands that accept thread IDs now accept the qualified
2198 INF_NUM.THR_NUM form as well. For example:
2201 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
2204 * In commands that accept a list of thread IDs, you can now refer to
2205 all threads of an inferior using a star wildcard. GDB accepts
2206 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
2207 refer to all threads of the current inferior. For example, "info
2210 * You can use "info threads -gid" to display the global thread ID of
2213 * The new convenience variable $_gthread holds the global number of
2216 * The new convenience variable $_inferior holds the number of the
2219 * GDB now displays the ID and name of the thread that hit a breakpoint
2220 or received a signal, if your program is multi-threaded. For
2223 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
2224 Thread 1 "main" received signal SIGINT, Interrupt.
2226 * Record btrace now supports non-stop mode.
2228 * Support for tracepoints on aarch64-linux was added in GDBserver.
2230 * The 'record instruction-history' command now indicates speculative execution
2231 when using the Intel Processor Trace recording format.
2233 * GDB now allows users to specify explicit locations, bypassing
2234 the linespec parser. This feature is also available to GDB/MI
2237 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
2238 GDB now is able to debug both AArch64 applications and ARM applications
2241 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
2242 including JIT compiling fast tracepoint's conditional expression bytecode
2245 * GDB now supports displaced stepping on AArch64 GNU/Linux.
2247 * "info threads", "info inferiors", "info display", "info checkpoints"
2248 and "maint info program-spaces" now list the corresponding items in
2249 ascending ID order, for consistency with all other "info" commands.
2251 * In Ada, the overloads selection menu has been enhanced to display the
2252 parameter types and the return types for the matching overloaded subprograms.
2256 maint set target-non-stop (on|off|auto)
2257 maint show target-non-stop
2258 Control whether GDB targets always operate in non-stop mode even if
2259 "set non-stop" is "off". The default is "auto", meaning non-stop
2260 mode is enabled if supported by the target.
2262 maint set bfd-sharing
2263 maint show bfd-sharing
2264 Control the reuse of bfd objects.
2267 show debug bfd-cache
2268 Control display of debugging info regarding bfd caching.
2272 Control display of debugging info regarding FreeBSD threads.
2274 set remote multiprocess-extensions-packet
2275 show remote multiprocess-extensions-packet
2276 Set/show the use of the remote protocol multiprocess extensions.
2278 set remote thread-events
2279 show remote thread-events
2280 Set/show the use of thread create/exit events.
2282 set ada print-signatures on|off
2283 show ada print-signatures"
2284 Control whether parameter types and return types are displayed in overloads
2285 selection menus. It is activated (@code{on}) by default.
2289 Controls the maximum size of memory, in bytes, that GDB will
2290 allocate for value contents. Prevents incorrect programs from
2291 causing GDB to allocate overly large buffers. Default is 64k.
2293 * The "disassemble" command accepts a new modifier: /s.
2294 It prints mixed source+disassembly like /m with two differences:
2295 - disassembled instructions are now printed in program order, and
2296 - and source for all relevant files is now printed.
2297 The "/m" option is now considered deprecated: its "source-centric"
2298 output hasn't proved useful in practice.
2300 * The "record instruction-history" command accepts a new modifier: /s.
2301 It behaves exactly like /m and prints mixed source+disassembly.
2303 * The "set scheduler-locking" command supports a new mode "replay".
2304 It behaves like "off" in record mode and like "on" in replay mode.
2306 * Support for various ROM monitors has been removed:
2308 target dbug dBUG ROM monitor for Motorola ColdFire
2309 target picobug Motorola picobug monitor
2310 target dink32 DINK32 ROM monitor for PowerPC
2311 target m32r Renesas M32R/D ROM monitor
2312 target mon2000 mon2000 ROM monitor
2313 target ppcbug PPCBUG ROM monitor for PowerPC
2315 * Support for reading/writing memory and extracting values on architectures
2316 whose memory is addressable in units of any integral multiple of 8 bits.
2319 Allows to break when an Ada exception is handled.
2321 * New remote packets
2324 Indicates that an exec system call was executed.
2326 exec-events feature in qSupported
2327 The qSupported packet allows GDB to request support for exec
2328 events using the new 'gdbfeature' exec-event, and the qSupported
2329 response can contain the corresponding 'stubfeature'. Set and
2330 show commands can be used to display whether these features are enabled.
2333 Equivalent to interrupting with the ^C character, but works in
2336 thread created stop reason (T05 create:...)
2337 Indicates that the thread was just created and is stopped at entry.
2339 thread exit stop reply (w exitcode;tid)
2340 Indicates that the thread has terminated.
2343 Enables/disables thread create and exit event reporting. For
2344 example, this is used in non-stop mode when GDB stops a set of
2345 threads and synchronously waits for the their corresponding stop
2346 replies. Without exit events, if one of the threads exits, GDB
2347 would hang forever not knowing that it should no longer expect a
2348 stop for that same thread.
2351 Indicates that there are no resumed threads left in the target (all
2352 threads are stopped). The remote stub reports support for this stop
2353 reply to GDB's qSupported query.
2356 Enables/disables catching syscalls from the inferior process.
2357 The remote stub reports support for this packet to GDB's qSupported query.
2359 syscall_entry stop reason
2360 Indicates that a syscall was just called.
2362 syscall_return stop reason
2363 Indicates that a syscall just returned.
2365 * Extended-remote exec events
2367 ** GDB now has support for exec events on extended-remote Linux targets.
2368 For such targets with Linux kernels 2.5.46 and later, this enables
2369 follow-exec-mode and exec catchpoints.
2371 set remote exec-event-feature-packet
2372 show remote exec-event-feature-packet
2373 Set/show the use of the remote exec event feature.
2375 * Thread names in remote protocol
2377 The reply to qXfer:threads:read may now include a name attribute for each
2380 * Target remote mode fork and exec events
2382 ** GDB now has support for fork and exec events on target remote mode
2383 Linux targets. For such targets with Linux kernels 2.5.46 and later,
2384 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
2385 fork and exec catchpoints.
2387 * Remote syscall events
2389 ** GDB now has support for catch syscall on remote Linux targets,
2390 currently enabled on x86/x86_64 architectures.
2392 set remote catch-syscall-packet
2393 show remote catch-syscall-packet
2394 Set/show the use of the remote catch syscall feature.
2398 ** The -var-set-format command now accepts the zero-hexadecimal
2399 format. It outputs data in hexadecimal format with zero-padding on the
2404 ** gdb.InferiorThread objects have a new attribute "global_num",
2405 which refers to the thread's global thread ID. The existing
2406 "num" attribute now refers to the thread's per-inferior number.
2407 See "Per-inferior thread numbers" above.
2408 ** gdb.InferiorThread objects have a new attribute "inferior", which
2409 is the Inferior object the thread belongs to.
2411 *** Changes in GDB 7.10
2413 * Support for process record-replay and reverse debugging on aarch64*-linux*
2414 targets has been added. GDB now supports recording of A64 instruction set
2415 including advance SIMD instructions.
2417 * Support for Sun's version of the "stabs" debug file format has been removed.
2419 * GDB now honors the content of the file /proc/PID/coredump_filter
2420 (PID is the process ID) on GNU/Linux systems. This file can be used
2421 to specify the types of memory mappings that will be included in a
2422 corefile. For more information, please refer to the manual page of
2423 "core(5)". GDB also has a new command: "set use-coredump-filter
2424 on|off". It allows to set whether GDB will read the content of the
2425 /proc/PID/coredump_filter file when generating a corefile.
2427 * The "info os" command on GNU/Linux can now display information on
2429 "info os cpus" Listing of all cpus/cores on the system
2431 * GDB has two new commands: "set serial parity odd|even|none" and
2432 "show serial parity". These allows to set or show parity for the
2435 * The "info source" command now displays the producer string if it was
2436 present in the debug info. This typically includes the compiler version
2437 and may include things like its command line arguments.
2439 * The "info dll", an alias of the "info sharedlibrary" command,
2440 is now available on all platforms.
2442 * Directory names supplied to the "set sysroot" commands may be
2443 prefixed with "target:" to tell GDB to access shared libraries from
2444 the target system, be it local or remote. This replaces the prefix
2445 "remote:". The default sysroot has been changed from "" to
2446 "target:". "remote:" is automatically converted to "target:" for
2447 backward compatibility.
2449 * The system root specified by "set sysroot" will be prepended to the
2450 filename of the main executable (if reported to GDB as absolute by
2451 the operating system) when starting processes remotely, and when
2452 attaching to already-running local or remote processes.
2454 * GDB now supports automatic location and retrieval of executable
2455 files from remote targets. Remote debugging can now be initiated
2456 using only a "target remote" or "target extended-remote" command
2457 (no "set sysroot" or "file" commands are required). See "New remote
2460 * The "dump" command now supports verilog hex format.
2462 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
2464 * On GNU/Linux, GDB and gdbserver are now able to access executable
2465 and shared library files without a "set sysroot" command when
2466 attaching to processes running in different mount namespaces from
2467 the debugger. This makes it possible to attach to processes in
2468 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
2469 See "New remote packets" below.
2471 * The "tui reg" command now provides completion for all of the
2472 available register groups, including target specific groups.
2474 * The HISTSIZE environment variable is no longer read when determining
2475 the size of GDB's command history. GDB now instead reads the dedicated
2476 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
2477 disables truncation of command history. Non-numeric values of GDBHISTSIZE
2482 ** Memory ports can now be unbuffered.
2486 ** gdb.Objfile objects have a new attribute "username",
2487 which is the name of the objfile as specified by the user,
2488 without, for example, resolving symlinks.
2489 ** You can now write frame unwinders in Python.
2490 ** gdb.Type objects have a new method "optimized_out",
2491 returning optimized out gdb.Value instance of this type.
2492 ** gdb.Value objects have new methods "reference_value" and
2493 "const_value" which return a reference to the value and a
2494 "const" version of the value respectively.
2498 maint print symbol-cache
2499 Print the contents of the symbol cache.
2501 maint print symbol-cache-statistics
2502 Print statistics of symbol cache usage.
2504 maint flush-symbol-cache
2505 Flush the contents of the symbol cache.
2509 Start branch trace recording using Branch Trace Store (BTS) format.
2512 Evaluate expression by using the compiler and print result.
2516 Explicit commands for enabling and disabling tui mode.
2519 set mpx bound on i386 and amd64
2520 Support for bound table investigation on Intel MPX enabled applications.
2524 Start branch trace recording using Intel Processor Trace format.
2527 Print information about branch tracing internals.
2529 maint btrace packet-history
2530 Print the raw branch tracing data.
2532 maint btrace clear-packet-history
2533 Discard the stored raw branch tracing data.
2536 Discard all branch tracing data. It will be fetched and processed
2537 anew by the next "record" command.
2542 Renamed from "set debug dwarf2-die".
2543 show debug dwarf-die
2544 Renamed from "show debug dwarf2-die".
2546 set debug dwarf-read
2547 Renamed from "set debug dwarf2-read".
2548 show debug dwarf-read
2549 Renamed from "show debug dwarf2-read".
2551 maint set dwarf always-disassemble
2552 Renamed from "maint set dwarf2 always-disassemble".
2553 maint show dwarf always-disassemble
2554 Renamed from "maint show dwarf2 always-disassemble".
2556 maint set dwarf max-cache-age
2557 Renamed from "maint set dwarf2 max-cache-age".
2558 maint show dwarf max-cache-age
2559 Renamed from "maint show dwarf2 max-cache-age".
2561 set debug dwarf-line
2562 show debug dwarf-line
2563 Control display of debugging info regarding DWARF line processing.
2566 show max-completions
2567 Set the maximum number of candidates to be considered during
2568 completion. The default value is 200. This limit allows GDB
2569 to avoid generating large completion lists, the computation of
2570 which can cause the debugger to become temporarily unresponsive.
2572 set history remove-duplicates
2573 show history remove-duplicates
2574 Control the removal of duplicate history entries.
2576 maint set symbol-cache-size
2577 maint show symbol-cache-size
2578 Control the size of the symbol cache.
2580 set|show record btrace bts buffer-size
2581 Set and show the size of the ring buffer used for branch tracing in
2583 The obtained size may differ from the requested size. Use "info
2584 record" to see the obtained buffer size.
2586 set debug linux-namespaces
2587 show debug linux-namespaces
2588 Control display of debugging info regarding Linux namespaces.
2590 set|show record btrace pt buffer-size
2591 Set and show the size of the ring buffer used for branch tracing in
2592 Intel Processor Trace format.
2593 The obtained size may differ from the requested size. Use "info
2594 record" to see the obtained buffer size.
2596 maint set|show btrace pt skip-pad
2597 Set and show whether PAD packets are skipped when computing the
2600 * The command 'thread apply all' can now support new option '-ascending'
2601 to call its specified command for all threads in ascending order.
2603 * Python/Guile scripting
2605 ** GDB now supports auto-loading of Python/Guile scripts contained in the
2606 special section named `.debug_gdb_scripts'.
2608 * New remote packets
2610 qXfer:btrace-conf:read
2611 Return the branch trace configuration for the current thread.
2613 Qbtrace-conf:bts:size
2614 Set the requested ring buffer size for branch tracing in BTS format.
2617 Enable Intel Processor Trace-based branch tracing for the current
2618 process. The remote stub reports support for this packet to GDB's
2621 Qbtrace-conf:pt:size
2622 Set the requested ring buffer size for branch tracing in Intel Processor
2626 Indicates a memory breakpoint instruction was executed, irrespective
2627 of whether it was GDB that planted the breakpoint or the breakpoint
2628 is hardcoded in the program. This is required for correct non-stop
2632 Indicates the target stopped for a hardware breakpoint. This is
2633 required for correct non-stop mode operation.
2636 Return information about files on the remote system.
2638 qXfer:exec-file:read
2639 Return the full absolute name of the file that was executed to
2640 create a process running on the remote system.
2643 Select the filesystem on which vFile: operations with filename
2644 arguments will operate. This is required for GDB to be able to
2645 access files on remote targets where the remote stub does not
2646 share a common filesystem with the inferior(s).
2649 Indicates that a fork system call was executed.
2652 Indicates that a vfork system call was executed.
2654 vforkdone stop reason
2655 Indicates that a vfork child of the specified process has executed
2656 an exec or exit, allowing the vfork parent to resume execution.
2658 fork-events and vfork-events features in qSupported
2659 The qSupported packet allows GDB to request support for fork and
2660 vfork events using new 'gdbfeatures' fork-events and vfork-events,
2661 and the qSupported response can contain the corresponding
2662 'stubfeatures'. Set and show commands can be used to display
2663 whether these features are enabled.
2665 * Extended-remote fork events
2667 ** GDB now has support for fork events on extended-remote Linux
2668 targets. For targets with Linux kernels 2.5.60 and later, this
2669 enables follow-fork-mode and detach-on-fork for both fork and
2670 vfork, as well as fork and vfork catchpoints.
2672 * The info record command now shows the recording format and the
2673 branch tracing configuration for the current thread when using
2674 the btrace record target.
2675 For the BTS format, it shows the ring buffer size.
2677 * GDB now has support for DTrace USDT (Userland Static Defined
2678 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
2680 * GDB now supports access to vector registers on S/390 GNU/Linux
2683 * Removed command line options
2685 -xdb HP-UX XDB compatibility mode.
2687 * Removed targets and native configurations
2689 HP/PA running HP-UX hppa*-*-hpux*
2690 Itanium running HP-UX ia64-*-hpux*
2692 * New configure options
2695 This configure option allows the user to build GDB with support for
2696 Intel Processor Trace (default: auto). This requires libipt.
2698 --with-libipt-prefix=PATH
2699 Specify the path to the version of libipt that GDB should use.
2700 $PATH/include should contain the intel-pt.h header and
2701 $PATH/lib should contain the libipt.so library.
2703 *** Changes in GDB 7.9.1
2707 ** Xmethods can now specify a result type.
2709 *** Changes in GDB 7.9
2711 * GDB now supports hardware watchpoints on x86 GNU Hurd.
2715 ** You can now access frame registers from Python scripts.
2716 ** New attribute 'producer' for gdb.Symtab objects.
2717 ** gdb.Objfile objects have a new attribute "progspace",
2718 which is the gdb.Progspace object of the containing program space.
2719 ** gdb.Objfile objects have a new attribute "owner".
2720 ** gdb.Objfile objects have a new attribute "build_id",
2721 which is the build ID generated when the file was built.
2722 ** gdb.Objfile objects have a new method "add_separate_debug_file".
2723 ** A new event "gdb.clear_objfiles" has been added, triggered when
2724 selecting a new file to debug.
2725 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
2726 ** New function gdb.lookup_objfile.
2728 New events which are triggered when GDB modifies the state of the
2731 ** gdb.events.inferior_call_pre: Function call is about to be made.
2732 ** gdb.events.inferior_call_post: Function call has just been made.
2733 ** gdb.events.memory_changed: A memory location has been altered.
2734 ** gdb.events.register_changed: A register has been altered.
2736 * New Python-based convenience functions:
2738 ** $_caller_is(name [, number_of_frames])
2739 ** $_caller_matches(regexp [, number_of_frames])
2740 ** $_any_caller_is(name [, number_of_frames])
2741 ** $_any_caller_matches(regexp [, number_of_frames])
2743 * GDB now supports the compilation and injection of source code into
2744 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
2745 to compile the source code to object code, and if successful, inject
2746 and execute that code within the current context of the inferior.
2747 Currently the C language is supported. The commands used to
2748 interface with this new feature are:
2750 compile code [-raw|-r] [--] [source code]
2751 compile file [-raw|-r] filename
2755 demangle [-l language] [--] name
2756 Demangle "name" in the specified language, or the current language
2757 if elided. This command is renamed from the "maint demangle" command.
2758 The latter is kept as a no-op to avoid "maint demangle" being interpreted
2759 as "maint demangler-warning".
2761 queue-signal signal-name-or-number
2762 Queue a signal to be delivered to the thread when it is resumed.
2764 add-auto-load-scripts-directory directory
2765 Add entries to the list of directories from which to load auto-loaded
2768 maint print user-registers
2769 List all currently available "user" registers.
2771 compile code [-r|-raw] [--] [source code]
2772 Compile, inject, and execute in the inferior the executable object
2773 code produced by compiling the provided source code.
2775 compile file [-r|-raw] filename
2776 Compile and inject into the inferior the executable object code
2777 produced by compiling the source code stored in the filename
2780 * On resume, GDB now always passes the signal the program had stopped
2781 for to the thread the signal was sent to, even if the user changed
2782 threads before resuming. Previously GDB would often (but not
2783 always) deliver the signal to the thread that happens to be current
2786 * Conversely, the "signal" command now consistently delivers the
2787 requested signal to the current thread. GDB now asks for
2788 confirmation if the program had stopped for a signal and the user
2789 switched threads meanwhile.
2791 * "breakpoint always-inserted" modes "off" and "auto" merged.
2793 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
2794 won't remove breakpoints from the target until all threads stop,
2795 even in non-stop mode. The "auto" mode has been removed, and "off"
2796 is now the default mode.
2800 set debug symbol-lookup
2801 show debug symbol-lookup
2802 Control display of debugging info regarding symbol lookup.
2806 ** The -list-thread-groups command outputs an exit-code field for
2807 inferiors that have exited.
2811 MIPS SDE mips*-sde*-elf*
2815 Support for these obsolete configurations has been removed.
2817 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
2818 SGI Irix-5.x mips-*-irix5*
2819 SGI Irix-6.x mips-*-irix6*
2820 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
2821 VAX running Ultrix vax-*-ultrix*
2823 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2824 and "assf"), have been removed. Use the "sharedlibrary" command, or
2825 its alias "share", instead.
2827 *** Changes in GDB 7.8
2829 * New command line options
2832 This is an alias for the --data-directory option.
2834 * GDB supports printing and modifying of variable length automatic arrays
2835 as specified in ISO C99.
2837 * The ARM simulator now supports instruction level tracing
2838 with or without disassembly.
2842 GDB now has support for scripting using Guile. Whether this is
2843 available is determined at configure time.
2844 Guile version 2.0 or greater is required.
2845 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
2847 * New commands (for set/show, see "New options" below)
2851 Invoke CODE by passing it to the Guile interpreter.
2855 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
2857 info auto-load guile-scripts [regexp]
2858 Print the list of automatically loaded Guile scripts.
2860 * The source command is now capable of sourcing Guile scripts.
2861 This feature is dependent on the debugger being built with Guile support.
2865 set print symbol-loading (off|brief|full)
2866 show print symbol-loading
2867 Control whether to print informational messages when loading symbol
2868 information for a file. The default is "full", but when debugging
2869 programs with large numbers of shared libraries the amount of output
2870 becomes less useful.
2872 set guile print-stack (none|message|full)
2873 show guile print-stack
2874 Show a stack trace when an error is encountered in a Guile script.
2876 set auto-load guile-scripts (on|off)
2877 show auto-load guile-scripts
2878 Control auto-loading of Guile script files.
2880 maint ada set ignore-descriptive-types (on|off)
2881 maint ada show ignore-descriptive-types
2882 Control whether the debugger should ignore descriptive types in Ada
2883 programs. The default is not to ignore the descriptive types. See
2884 the user manual for more details on descriptive types and the intended
2885 usage of this option.
2887 set auto-connect-native-target
2889 Control whether GDB is allowed to automatically connect to the
2890 native target for the run, attach, etc. commands when not connected
2891 to any target yet. See also "target native" below.
2893 set record btrace replay-memory-access (read-only|read-write)
2894 show record btrace replay-memory-access
2895 Control what memory accesses are allowed during replay.
2897 maint set target-async (on|off)
2898 maint show target-async
2899 This controls whether GDB targets operate in synchronous or
2900 asynchronous mode. Normally the default is asynchronous, if it is
2901 available; but this can be changed to more easily debug problems
2902 occurring only in synchronous mode.
2904 set mi-async (on|off)
2906 Control whether MI asynchronous mode is preferred. This supersedes
2907 "set target-async" of previous GDB versions.
2909 * "set target-async" is deprecated as a CLI option and is now an alias
2910 for "set mi-async" (only puts MI into async mode).
2912 * Background execution commands (e.g., "c&", "s&", etc.) are now
2913 possible ``out of the box'' if the target supports them. Previously
2914 the user would need to explicitly enable the possibility with the
2915 "set target-async on" command.
2917 * New features in the GDB remote stub, GDBserver
2919 ** New option --debug-format=option1[,option2,...] allows one to add
2920 additional text to each output. At present only timestamps
2921 are supported: --debug-format=timestamps.
2922 Timestamps can also be turned on with the
2923 "monitor set debug-format timestamps" command from GDB.
2925 * The 'record instruction-history' command now starts counting instructions
2926 at one. This also affects the instruction ranges reported by the
2927 'record function-call-history' command when given the /i modifier.
2929 * The command 'record function-call-history' supports a new modifier '/c' to
2930 indent the function names based on their call stack depth.
2931 The fields for the '/i' and '/l' modifier have been reordered.
2932 The source line range is now prefixed with 'at'.
2933 The instruction range is now prefixed with 'inst'.
2934 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
2935 "record instruction-history" and "list" commands.
2937 * The ranges given as arguments to the 'record function-call-history' and
2938 'record instruction-history' commands are now inclusive.
2940 * The btrace record target now supports the 'record goto' command.
2941 For locations inside the execution trace, the back trace is computed
2942 based on the information stored in the execution trace.
2944 * The btrace record target supports limited reverse execution and replay.
2945 The target does not record data and therefore does not allow reading
2946 memory or registers.
2948 * The "catch syscall" command now works on s390*-linux* targets.
2950 * The "compare-sections" command is no longer specific to target
2951 remote. It now works with all targets.
2953 * All native targets are now consistently called "native".
2954 Consequently, the "target child", "target GNU", "target djgpp",
2955 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
2956 commands have been replaced with "target native". The QNX/NTO port
2957 leaves the "procfs" target in place and adds a "native" target for
2958 consistency with other ports. The impact on users should be minimal
2959 as these commands previously either throwed an error, or were
2960 no-ops. The target's name is visible in the output of the following
2961 commands: "help target", "info target", "info files", "maint print
2964 * The "target native" command now connects to the native target. This
2965 can be used to launch native programs even when "set
2966 auto-connect-native-target" is set to off.
2968 * GDB now supports access to Intel MPX registers on GNU/Linux.
2970 * Support for Intel AVX-512 registers on GNU/Linux.
2971 Support displaying and modifying Intel AVX-512 registers
2972 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
2974 * New remote packets
2976 qXfer:btrace:read's annex
2977 The qXfer:btrace:read packet supports a new annex 'delta' to read
2978 branch trace incrementally.
2982 ** Valid Python operations on gdb.Value objects representing
2983 structs/classes invoke the corresponding overloaded operators if
2985 ** New `Xmethods' feature in the Python API. Xmethods are
2986 additional methods or replacements for existing methods of a C++
2987 class. This feature is useful for those cases where a method
2988 defined in C++ source code could be inlined or optimized out by
2989 the compiler, making it unavailable to GDB.
2992 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
2994 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2995 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
2996 its alias "share", instead.
2998 * The commands "set remotebaud" and "show remotebaud" are no longer
2999 supported. Use "set serial baud" and "show serial baud" (respectively)
3004 ** A new option "-gdb-set mi-async" replaces "-gdb-set
3005 target-async". The latter is left as a deprecated alias of the
3006 former for backward compatibility. If the target supports it,
3007 CLI background execution commands are now always possible by
3008 default, independently of whether the frontend stated a
3009 preference for asynchronous execution with "-gdb-set mi-async".
3010 Previously "-gdb-set target-async off" affected both MI execution
3011 commands and CLI execution commands.
3013 *** Changes in GDB 7.7
3015 * Improved support for process record-replay and reverse debugging on
3016 arm*-linux* targets. Support for thumb32 and syscall instruction
3017 recording has been added.
3019 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
3021 * GDB now supports Fission DWP file format version 2.
3022 http://gcc.gnu.org/wiki/DebugFission
3024 * New convenience function "$_isvoid", to check whether an expression
3025 is void. A void expression is an expression where the type of the
3026 result is "void". For example, some convenience variables may be
3027 "void" when evaluated (e.g., "$_exitcode" before the execution of
3028 the program being debugged; or an undefined convenience variable).
3029 Another example, when calling a function whose return type is
3032 * The "maintenance print objfiles" command now takes an optional regexp.
3034 * The "catch syscall" command now works on arm*-linux* targets.
3036 * GDB now consistently shows "<not saved>" when printing values of
3037 registers the debug info indicates have not been saved in the frame
3038 and there's nowhere to retrieve them from
3039 (callee-saved/call-clobbered registers):
3044 (gdb) info registers rax
3047 Before, the former would print "<optimized out>", and the latter
3048 "*value not available*".
3050 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
3055 ** Frame filters and frame decorators have been added.
3056 ** Temporary breakpoints are now supported.
3057 ** Line tables representation has been added.
3058 ** New attribute 'parent_type' for gdb.Field objects.
3059 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
3060 ** New attribute 'name' for gdb.Type objects.
3064 Nios II ELF nios2*-*-elf
3065 Nios II GNU/Linux nios2*-*-linux
3066 Texas Instruments MSP430 msp430*-*-elf
3068 * Removed native configurations
3070 Support for these a.out NetBSD and OpenBSD obsolete configurations has
3071 been removed. ELF variants of these configurations are kept supported.
3073 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
3074 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
3075 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
3076 i[34567]86-*-openbsd3.[0-3]
3077 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
3078 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
3079 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
3083 Like "catch throw", but catches a re-thrown exception.
3084 maint check-psymtabs
3085 Renamed from old "maint check-symtabs".
3087 Perform consistency checks on symtabs.
3088 maint expand-symtabs
3089 Expand symtabs matching an optional regexp.
3092 Display the details of GDB configure-time options.
3094 maint set|show per-command
3095 maint set|show per-command space
3096 maint set|show per-command time
3097 maint set|show per-command symtab
3098 Enable display of per-command gdb resource usage.
3100 remove-symbol-file FILENAME
3101 remove-symbol-file -a ADDRESS
3102 Remove a symbol file added via add-symbol-file. The file to remove
3103 can be identified by its filename or by an address that lies within
3104 the boundaries of this symbol file in memory.
3107 info exceptions REGEXP
3108 Display the list of Ada exceptions defined in the program being
3109 debugged. If provided, only the exceptions whose names match REGEXP
3114 set debug symfile off|on
3116 Control display of debugging info regarding reading symbol files and
3117 symbol tables within those files
3119 set print raw frame-arguments
3120 show print raw frame-arguments
3121 Set/show whether to print frame arguments in raw mode,
3122 disregarding any defined pretty-printers.
3124 set remote trace-status-packet
3125 show remote trace-status-packet
3126 Set/show the use of remote protocol qTStatus packet.
3130 Control display of debugging messages related to Nios II targets.
3134 Control whether target-assisted range stepping is enabled.
3136 set startup-with-shell
3137 show startup-with-shell
3138 Specifies whether Unix child processes are started via a shell or
3143 Use the target memory cache for accesses to the code segment. This
3144 improves performance of remote debugging (particularly disassembly).
3146 * You can now use a literal value 'unlimited' for options that
3147 interpret 0 or -1 as meaning "unlimited". E.g., "set
3148 trace-buffer-size unlimited" is now an alias for "set
3149 trace-buffer-size -1" and "set height unlimited" is now an alias for
3152 * The "set debug symtab-create" debugging option of GDB has been changed to
3153 accept a verbosity level. 0 means "off", 1 provides basic debugging
3154 output, and values of 2 or greater provides more verbose output.
3156 * New command-line options
3158 Display the details of GDB configure-time options.
3160 * The command 'tsave' can now support new option '-ctf' to save trace
3161 buffer in Common Trace Format.
3163 * Newly installed $prefix/bin/gcore acts as a shell interface for the
3166 * GDB now implements the C++ 'typeid' operator.
3168 * The new convenience variable $_exception holds the exception being
3169 thrown or caught at an exception-related catchpoint.
3171 * The exception-related catchpoints, like "catch throw", now accept a
3172 regular expression which can be used to filter exceptions by type.
3174 * The new convenience variable $_exitsignal is automatically set to
3175 the terminating signal number when the program being debugged dies
3176 due to an uncaught signal.
3180 ** All MI commands now accept an optional "--language" option.
3181 Support for this feature can be verified by using the "-list-features"
3182 command, which should contain "language-option".
3184 ** The new command -info-gdb-mi-command allows the user to determine
3185 whether a GDB/MI command is supported or not.
3187 ** The "^error" result record returned when trying to execute an undefined
3188 GDB/MI command now provides a variable named "code" whose content is the
3189 "undefined-command" error code. Support for this feature can be verified
3190 by using the "-list-features" command, which should contain
3191 "undefined-command-error-code".
3193 ** The -trace-save MI command can optionally save trace buffer in Common
3196 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
3198 ** The command -data-list-register-values now accepts an optional
3199 "--skip-unavailable" option. When used, only the available registers
3202 ** The new command -trace-frame-collected dumps collected variables,
3203 computed expressions, tvars, memory and registers in a traceframe.
3205 ** The commands -stack-list-locals, -stack-list-arguments and
3206 -stack-list-variables now accept an option "--skip-unavailable".
3207 When used, only the available locals or arguments are displayed.
3209 ** The -exec-run command now accepts an optional "--start" option.
3210 When used, the command follows the same semantics as the "start"
3211 command, stopping the program's execution at the start of its
3212 main subprogram. Support for this feature can be verified using
3213 the "-list-features" command, which should contain
3214 "exec-run-start-option".
3216 ** The new commands -catch-assert and -catch-exceptions insert
3217 catchpoints stopping the program when Ada exceptions are raised.
3219 ** The new command -info-ada-exceptions provides the equivalent of
3220 the new "info exceptions" command.
3222 * New system-wide configuration scripts
3223 A GDB installation now provides scripts suitable for use as system-wide
3224 configuration scripts for the following systems:
3228 * GDB now supports target-assigned range stepping with remote targets.
3229 This improves the performance of stepping source lines by reducing
3230 the number of control packets from/to GDB. See "New remote packets"
3233 * GDB now understands the element 'tvar' in the XML traceframe info.
3234 It has the id of the collected trace state variables.
3236 * On S/390 targets that provide the transactional-execution feature,
3237 the program interruption transaction diagnostic block (TDB) is now
3238 represented as a number of additional "registers" in GDB.
3240 * New remote packets
3244 The vCont packet supports a new 'r' action, that tells the remote
3245 stub to step through an address range itself, without GDB
3246 involvemement at each single-step.
3248 qXfer:libraries-svr4:read's annex
3249 The previously unused annex of the qXfer:libraries-svr4:read packet
3250 is now used to support passing an argument list. The remote stub
3251 reports support for this argument list to GDB's qSupported query.
3252 The defined arguments are "start" and "prev", used to reduce work
3253 necessary for library list updating, resulting in significant
3256 * New features in the GDB remote stub, GDBserver
3258 ** GDBserver now supports target-assisted range stepping. Currently
3259 enabled on x86/x86_64 GNU/Linux targets.
3261 ** GDBserver now adds element 'tvar' in the XML in the reply to
3262 'qXfer:traceframe-info:read'. It has the id of the collected
3263 trace state variables.
3265 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
3268 * New 'z' formatter for printing and examining memory, this displays the
3269 value as hexadecimal zero padded on the left to the size of the type.
3271 * GDB can now use Windows x64 unwinding data.
3273 * The "set remotebaud" command has been replaced by "set serial baud".
3274 Similarly, "show remotebaud" has been replaced by "show serial baud".
3275 The "set remotebaud" and "show remotebaud" commands are still available
3276 to provide backward compatibility with older versions of GDB.
3278 *** Changes in GDB 7.6
3280 * Target record has been renamed to record-full.
3281 Record/replay is now enabled with the "record full" command.
3282 This also affects settings that are associated with full record/replay
3283 that have been moved from "set/show record" to "set/show record full":
3285 set|show record full insn-number-max
3286 set|show record full stop-at-limit
3287 set|show record full memory-query
3289 * A new record target "record-btrace" has been added. The new target
3290 uses hardware support to record the control-flow of a process. It
3291 does not support replaying the execution, but it implements the
3292 below new commands for investigating the recorded execution log.
3293 This new recording method can be enabled using:
3297 The "record-btrace" target is only available on Intel Atom processors
3298 and requires a Linux kernel 2.6.32 or later.
3300 * Two new commands have been added for record/replay to give information
3301 about the recorded execution without having to replay the execution.
3302 The commands are only supported by "record btrace".
3304 record instruction-history prints the execution history at
3305 instruction granularity
3307 record function-call-history prints the execution history at
3308 function granularity
3310 * New native configurations
3312 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
3313 FreeBSD/powerpc powerpc*-*-freebsd
3314 x86_64/Cygwin x86_64-*-cygwin*
3315 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
3319 ARM AArch64 aarch64*-*-elf
3320 ARM AArch64 GNU/Linux aarch64*-*-linux
3321 Lynx 178 PowerPC powerpc-*-lynx*178
3322 x86_64/Cygwin x86_64-*-cygwin*
3323 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
3325 * If the configured location of system.gdbinit file (as given by the
3326 --with-system-gdbinit option at configure time) is in the
3327 data-directory (as specified by --with-gdb-datadir at configure
3328 time) or in one of its subdirectories, then GDB will look for the
3329 system-wide init file in the directory specified by the
3330 --data-directory command-line option.
3332 * New command line options:
3334 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
3335 other initialization files, unlike -nx which disables all of them.
3337 * Removed command line options
3339 -epoch This was used by the gdb mode in Epoch, an ancient fork of
3342 * The 'ptype' and 'whatis' commands now accept an argument to control
3345 * 'info proc' now works on some core files.
3349 ** Vectors can be created with gdb.Type.vector.
3351 ** Python's atexit.register now works in GDB.
3353 ** Types can be pretty-printed via a Python API.
3355 ** Python 3 is now supported (in addition to Python 2.4 or later)
3357 ** New class gdb.Architecture exposes GDB's internal representation
3358 of architecture in the Python API.
3360 ** New method Frame.architecture returns the gdb.Architecture object
3361 corresponding to the frame's architecture.
3363 * New Python-based convenience functions:
3365 ** $_memeq(buf1, buf2, length)
3366 ** $_streq(str1, str2)
3368 ** $_regex(str, regex)
3370 * The 'cd' command now defaults to using '~' (the home directory) if not
3373 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
3374 default for GCC since November 2000.
3376 * The command 'forward-search' can now be abbreviated as 'fo'.
3378 * The command 'info tracepoints' can now display 'installed on target'
3379 or 'not installed on target' for each non-pending location of tracepoint.
3381 * New configure options
3383 --enable-libmcheck/--disable-libmcheck
3384 By default, development versions are built with -lmcheck on hosts
3385 that support it, in order to help track memory corruption issues.
3386 Release versions, on the other hand, are built without -lmcheck
3387 by default. The --enable-libmcheck/--disable-libmcheck configure
3388 options allow the user to override that default.
3389 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
3390 This configure option allows the user to build GDB with
3391 libbabeltrace using which GDB can read Common Trace Format data.
3393 * New commands (for set/show, see "New options" below)
3396 Catch signals. This is similar to "handle", but allows commands and
3397 conditions to be attached.
3400 List the BFDs known to GDB.
3402 python-interactive [command]
3404 Start a Python interactive prompt, or evaluate the optional command
3405 and print the result of expressions.
3408 "py" is a new alias for "python".
3410 enable type-printer [name]...
3411 disable type-printer [name]...
3412 Enable or disable type printers.
3416 ** For the Renesas Super-H architecture, the "regs" command has been removed
3417 (has been deprecated in GDB 7.5), and "info all-registers" should be used
3422 set print type methods (on|off)
3423 show print type methods
3424 Control whether method declarations are displayed by "ptype".
3425 The default is to show them.
3427 set print type typedefs (on|off)
3428 show print type typedefs
3429 Control whether typedef definitions are displayed by "ptype".
3430 The default is to show them.
3432 set filename-display basename|relative|absolute
3433 show filename-display
3434 Control the way in which filenames is displayed.
3435 The default is "relative", which preserves previous behavior.
3437 set trace-buffer-size
3438 show trace-buffer-size
3439 Request target to change the size of trace buffer.
3441 set remote trace-buffer-size-packet auto|on|off
3442 show remote trace-buffer-size-packet
3443 Control the use of the remote protocol `QTBuffer:size' packet.
3447 Control display of debugging messages related to ARM AArch64.
3450 set debug coff-pe-read
3451 show debug coff-pe-read
3452 Control display of debugging messages related to reading of COFF/PE
3457 Control display of debugging messages related to Mach-O symbols
3460 set debug notification
3461 show debug notification
3462 Control display of debugging info for async remote notification.
3466 ** Command parameter changes are now notified using new async record
3467 "=cmd-param-changed".
3468 ** Trace frame changes caused by command "tfind" are now notified using
3469 new async record "=traceframe-changed".
3470 ** The creation, deletion and modification of trace state variables
3471 are now notified using new async records "=tsv-created",
3472 "=tsv-deleted" and "=tsv-modified".
3473 ** The start and stop of process record are now notified using new
3474 async record "=record-started" and "=record-stopped".
3475 ** Memory changes are now notified using new async record
3477 ** The data-disassemble command response will include a "fullname" field
3478 containing the absolute file name when source has been requested.
3479 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
3480 command, to allow pattern filling of memory areas.
3481 ** New commands "-catch-load"/"-catch-unload" added for intercepting
3482 library load/unload events.
3483 ** The response to breakpoint commands and breakpoint async records
3484 includes an "installed" field containing a boolean state about each
3485 non-pending tracepoint location is whether installed on target or not.
3486 ** Output of the "-trace-status" command includes a "trace-file" field
3487 containing the name of the trace file being examined. This field is
3488 optional, and only present when examining a trace file.
3489 ** The "fullname" field is now always present along with the "file" field,
3490 even if the file cannot be found by GDB.
3492 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
3493 You must have the LZMA library available when configuring GDB for this
3494 feature to be enabled. For more information, see:
3495 http://fedoraproject.org/wiki/Features/MiniDebugInfo
3497 * New remote packets
3500 Set the size of trace buffer. The remote stub reports support for this
3501 packet to gdb's qSupported query.
3504 Enable Branch Trace Store (BTS)-based branch tracing for the current
3505 thread. The remote stub reports support for this packet to gdb's
3509 Disable branch tracing for the current thread. The remote stub reports
3510 support for this packet to gdb's qSupported query.
3513 Read the traced branches for the current thread. The remote stub
3514 reports support for this packet to gdb's qSupported query.
3516 *** Changes in GDB 7.5
3518 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
3519 for more x32 ABI info.
3521 * GDB now supports access to MIPS DSP registers on Linux targets.
3523 * GDB now supports debugging microMIPS binaries.
3525 * The "info os" command on GNU/Linux can now display information on
3526 several new classes of objects managed by the operating system:
3527 "info os procgroups" lists process groups
3528 "info os files" lists file descriptors
3529 "info os sockets" lists internet-domain sockets
3530 "info os shm" lists shared-memory regions
3531 "info os semaphores" lists semaphores
3532 "info os msg" lists message queues
3533 "info os modules" lists loaded kernel modules
3535 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
3536 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
3537 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
3538 options and inspect the probe arguments using the new $_probe_arg family
3539 of convenience variables. You can obtain more information about SystemTap
3540 in <http://sourceware.org/systemtap/>.
3542 * GDB now supports reversible debugging on ARM, it allows you to
3543 debug basic ARM and THUMB instructions, and provides
3544 record/replay support.
3546 * The option "symbol-reloading" has been deleted as it is no longer used.
3550 ** GDB commands implemented in Python can now be put in command class
3553 ** The "maint set python print-stack on|off" is now deleted.
3555 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
3556 apply "flag enum"-style pretty-printing to any enum.
3558 ** gdb.lookup_symbol can now work when there is no current frame.
3560 ** gdb.Symbol now has a 'line' attribute, holding the line number in
3561 the source at which the symbol was defined.
3563 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
3564 method 'value'. The former indicates whether the symbol needs a
3565 frame in order to compute its value, and the latter computes the
3568 ** A new method 'referenced_value' on gdb.Value objects which can
3569 dereference pointer as well as C++ reference values.
3571 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
3572 which return the global and static blocks (as gdb.Block objects),
3573 of the underlying symbol table, respectively.
3575 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
3576 object associated with a PC value.
3578 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
3579 of the address range occupied by code for the current source line.
3581 * Go language support.
3582 GDB now supports debugging programs written in the Go programming
3585 * GDBserver now supports stdio connections.
3586 E.g. (gdb) target remote | ssh myhost gdbserver - hello
3588 * The binary "gdbtui" can no longer be built or installed.
3589 Use "gdb -tui" instead.
3591 * GDB will now print "flag" enums specially. A flag enum is one where
3592 all the enumerator values have no bits in common when pairwise
3593 "and"ed. When printing a value whose type is a flag enum, GDB will
3594 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
3595 (gdb) print (enum E) 3
3598 * The filename part of a linespec will now match trailing components
3599 of a source file name. For example, "break gcc/expr.c:1000" will
3600 now set a breakpoint in build/gcc/expr.c, but not
3601 build/libcpp/expr.c.
3603 * The "info proc" and "generate-core-file" commands will now also
3604 work on remote targets connected to GDBserver on Linux.
3606 * The command "info catch" has been removed. It has been disabled
3607 since December 2007.
3609 * The "catch exception" and "catch assert" commands now accept
3610 a condition at the end of the command, much like the "break"
3611 command does. For instance:
3613 (gdb) catch exception Constraint_Error if Barrier = True
3615 Previously, it was possible to add a condition to such catchpoints,
3616 but it had to be done as a second step, after the catchpoint had been
3617 created, using the "condition" command.
3619 * The "info static-tracepoint-marker" command will now also work on
3620 native Linux targets with in-process agent.
3622 * GDB can now set breakpoints on inlined functions.
3624 * The .gdb_index section has been updated to include symbols for
3625 inlined functions. GDB will ignore older .gdb_index sections by
3626 default, which could cause symbol files to be loaded more slowly
3627 until their .gdb_index sections can be recreated. The new command
3628 "set use-deprecated-index-sections on" will cause GDB to use any older
3629 .gdb_index sections it finds. This will restore performance, but the
3630 ability to set breakpoints on inlined functions will be lost in symbol
3631 files with older .gdb_index sections.
3633 The .gdb_index section has also been updated to record more information
3634 about each symbol. This speeds up the "info variables", "info functions"
3635 and "info types" commands when used with programs having the .gdb_index
3636 section, as well as speeding up debugging with shared libraries using
3637 the .gdb_index section.
3639 * Ada support for GDB/MI Variable Objects has been added.
3641 * GDB can now support 'breakpoint always-inserted mode' in 'record'
3646 ** New command -info-os is the MI equivalent of "info os".
3648 ** Output logs ("set logging" and related) now include MI output.
3652 ** "set use-deprecated-index-sections on|off"
3653 "show use-deprecated-index-sections on|off"
3654 Controls the use of deprecated .gdb_index sections.
3656 ** "catch load" and "catch unload" can be used to stop when a shared
3657 library is loaded or unloaded, respectively.
3659 ** "enable count" can be used to auto-disable a breakpoint after
3662 ** "info vtbl" can be used to show the virtual method tables for
3663 C++ and Java objects.
3665 ** "explore" and its sub commands "explore value" and "explore type"
3666 can be used to recursively explore values and types of
3667 expressions. These commands are available only if GDB is
3668 configured with '--with-python'.
3670 ** "info auto-load" shows status of all kinds of auto-loaded files,
3671 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
3672 sequences of commands files, "info auto-load python-scripts"
3673 shows status of auto-loading Python script files,
3674 "info auto-load local-gdbinit" shows status of loading init file
3675 (.gdbinit) from current directory and "info auto-load libthread-db" shows
3676 status of inferior specific thread debugging shared library loading.
3678 ** "info auto-load-scripts", "set auto-load-scripts on|off"
3679 and "show auto-load-scripts" commands have been deprecated, use their
3680 "info auto-load python-scripts", "set auto-load python-scripts on|off"
3681 and "show auto-load python-scripts" counterparts instead.
3683 ** "dprintf location,format,args..." creates a dynamic printf, which
3684 is basically a breakpoint that does a printf and immediately
3685 resumes your program's execution, so it is like a printf that you
3686 can insert dynamically at runtime instead of at compiletime.
3688 ** "set print symbol"
3690 Controls whether GDB attempts to display the symbol, if any,
3691 corresponding to addresses it prints. This defaults to "on", but
3692 you can set it to "off" to restore GDB's previous behavior.
3694 * Deprecated commands
3696 ** For the Renesas Super-H architecture, the "regs" command has been
3697 deprecated, and "info all-registers" should be used instead.
3701 Renesas RL78 rl78-*-elf
3702 HP OpenVMS ia64 ia64-hp-openvms*
3704 * GDBserver supports evaluation of breakpoint conditions. When
3705 support is advertised by GDBserver, GDB may be told to send the
3706 breakpoint conditions in bytecode form to GDBserver. GDBserver
3707 will only report the breakpoint trigger to GDB when its condition
3712 set mips compression
3713 show mips compression
3714 Select the compressed ISA encoding used in functions that have no symbol
3715 information available. The encoding can be set to either of:
3718 and is updated automatically from ELF file flags if available.
3720 set breakpoint condition-evaluation
3721 show breakpoint condition-evaluation
3722 Control whether breakpoint conditions are evaluated by GDB ("host") or by
3723 GDBserver ("target"). Default option "auto" chooses the most efficient
3725 This option can improve debugger efficiency depending on the speed of the
3729 Disable auto-loading globally.
3732 Show auto-loading setting of all kinds of auto-loaded files.
3734 set auto-load gdb-scripts on|off
3735 show auto-load gdb-scripts
3736 Control auto-loading of GDB canned sequences of commands files.
3738 set auto-load python-scripts on|off
3739 show auto-load python-scripts
3740 Control auto-loading of Python script files.
3742 set auto-load local-gdbinit on|off
3743 show auto-load local-gdbinit
3744 Control loading of init file (.gdbinit) from current directory.
3746 set auto-load libthread-db on|off
3747 show auto-load libthread-db
3748 Control auto-loading of inferior specific thread debugging shared library.
3750 set auto-load scripts-directory <dir1>[:<dir2>...]
3751 show auto-load scripts-directory
3752 Set a list of directories from which to load auto-loaded scripts.
3753 Automatically loaded Python scripts and GDB scripts are located in one
3754 of the directories listed by this option.
3755 The delimiter (':' above) may differ according to the host platform.
3757 set auto-load safe-path <dir1>[:<dir2>...]
3758 show auto-load safe-path
3759 Set a list of directories from which it is safe to auto-load files.
3760 The delimiter (':' above) may differ according to the host platform.
3762 set debug auto-load on|off
3763 show debug auto-load
3764 Control display of debugging info for auto-loading the files above.
3766 set dprintf-style gdb|call|agent
3768 Control the way in which a dynamic printf is performed; "gdb"
3769 requests a GDB printf command, while "call" causes dprintf to call a
3770 function in the inferior. "agent" requests that the target agent
3771 (such as GDBserver) do the printing.
3773 set dprintf-function <expr>
3774 show dprintf-function
3775 set dprintf-channel <expr>
3776 show dprintf-channel
3777 Set the function and optional first argument to the call when using
3778 the "call" style of dynamic printf.
3780 set disconnected-dprintf on|off
3781 show disconnected-dprintf
3782 Control whether agent-style dynamic printfs continue to be in effect
3783 after GDB disconnects.
3785 * New configure options
3787 --with-auto-load-dir
3788 Configure default value for the 'set auto-load scripts-directory'
3789 setting above. It defaults to '$debugdir:$datadir/auto-load',
3790 $debugdir representing global debugging info directories (available
3791 via 'show debug-file-directory') and $datadir representing GDB's data
3792 directory (available via 'show data-directory').
3794 --with-auto-load-safe-path
3795 Configure default value for the 'set auto-load safe-path' setting
3796 above. It defaults to the --with-auto-load-dir setting.
3798 --without-auto-load-safe-path
3799 Set 'set auto-load safe-path' to '/', effectively disabling this
3802 * New remote packets
3804 z0/z1 conditional breakpoints extension
3806 The z0/z1 breakpoint insertion packets have been extended to carry
3807 a list of conditional expressions over to the remote stub depending on the
3808 condition evaluation mode. The use of this extension can be controlled
3809 via the "set remote conditional-breakpoints-packet" command.
3813 Specify the signals which the remote stub may pass to the debugged
3814 program without GDB involvement.
3816 * New command line options
3818 --init-command=FILE, -ix Like --command, -x but execute it
3819 before loading inferior.
3820 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
3821 execute it before loading inferior.
3823 *** Changes in GDB 7.4
3825 * GDB now handles ambiguous linespecs more consistently; the existing
3826 FILE:LINE support has been expanded to other types of linespecs. A
3827 breakpoint will now be set on all matching locations in all
3828 inferiors, and locations will be added or removed according to
3831 * GDB now allows you to skip uninteresting functions and files when
3832 stepping with the "skip function" and "skip file" commands.
3834 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
3835 and "show remote hardware-watchpoint-length-limit". These allows to
3836 set or show the maximum length limit (in bytes) of a remote
3837 target hardware watchpoint.
3839 This allows e.g. to use "unlimited" hardware watchpoints with the
3840 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
3841 watchpoints are slower than real hardware watchpoints but are
3842 significantly faster than gdb software watchpoints.
3846 ** The register_pretty_printer function in module gdb.printing now takes
3847 an optional `replace' argument. If True, the new printer replaces any
3850 ** The "maint set python print-stack on|off" command has been
3851 deprecated and will be deleted in GDB 7.5.
3852 A new command: "set python print-stack none|full|message" has
3853 replaced it. Additionally, the default for "print-stack" is
3854 now "message", which just prints the error message without
3857 ** A prompt substitution hook (prompt_hook) is now available to the
3860 ** A new Python module, gdb.prompt has been added to the GDB Python
3861 modules library. This module provides functionality for
3862 escape sequences in prompts (used by set/show
3863 extended-prompt). These escape sequences are replaced by their
3864 corresponding value.
3866 ** Python commands and convenience-functions located in
3867 'data-directory'/python/gdb/command and
3868 'data-directory'/python/gdb/function are now automatically loaded
3871 ** Blocks now provide four new attributes. global_block and
3872 static_block will return the global and static blocks
3873 respectively. is_static and is_global are boolean attributes
3874 that indicate if the block is one of those two types.
3876 ** Symbols now provide the "type" attribute, the type of the symbol.
3878 ** The "gdb.breakpoint" function has been deprecated in favor of
3881 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
3882 of a function. This class is based on the "finish" command
3883 available in the CLI.
3885 ** Type objects for struct and union types now allow access to
3886 the fields using standard Python dictionary (mapping) methods.
3887 For example, "some_type['myfield']" now works, as does
3888 "some_type.items()".
3890 ** A new event "gdb.new_objfile" has been added, triggered by loading a
3893 ** A new function, "deep_items" has been added to the gdb.types
3894 module in the GDB Python modules library. This function returns
3895 an iterator over the fields of a struct or union type. Unlike
3896 the standard Python "iteritems" method, it will recursively traverse
3897 any anonymous fields.
3901 ** "*stopped" events can report several new "reason"s, such as
3904 ** Breakpoint changes are now notified using new async records, like
3905 "=breakpoint-modified".
3907 ** New command -ada-task-info.
3909 * libthread-db-search-path now supports two special values: $sdir and $pdir.
3910 $sdir specifies the default system locations of shared libraries.
3911 $pdir specifies the directory where the libpthread used by the application
3914 GDB no longer looks in $sdir and $pdir after it has searched the directories
3915 mentioned in libthread-db-search-path. If you want to search those
3916 directories, they must be specified in libthread-db-search-path.
3917 The default value of libthread-db-search-path on GNU/Linux and Solaris
3918 systems is now "$sdir:$pdir".
3920 $pdir is not supported by gdbserver, it is currently ignored.
3921 $sdir is supported by gdbserver.
3923 * New configure option --with-iconv-bin.
3924 When using the internationalization support like the one in the GNU C
3925 library, GDB will invoke the "iconv" program to get a list of supported
3926 character sets. If this program lives in a non-standard location, one can
3927 use this option to specify where to find it.
3929 * When natively debugging programs on PowerPC BookE processors running
3930 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
3931 watchpoints, which specify a mask in addition to an address to watch.
3932 The mask specifies that some bits of an address (the bits which are
3933 reset in the mask) should be ignored when matching the address accessed
3934 by the inferior against the watchpoint address. See the "PowerPC Embedded"
3935 section in the user manual for more details.
3937 * The new option --once causes GDBserver to stop listening for connections once
3938 the first connection is made. The listening port used by GDBserver will
3939 become available after that.
3941 * New commands "info macros" and "alias" have been added.
3943 * New function parameters suffix @entry specifies value of function parameter
3944 at the time the function got called. Entry values are available only since
3950 "!" is now an alias of the "shell" command.
3951 Note that no space is needed between "!" and SHELL COMMAND.
3955 watch EXPRESSION mask MASK_VALUE
3956 The watch command now supports the mask argument which allows creation
3957 of masked watchpoints, if the current architecture supports this feature.
3959 info auto-load-scripts [REGEXP]
3960 This command was formerly named "maintenance print section-scripts".
3961 It is now generally useful and is no longer a maintenance-only command.
3963 info macro [-all] [--] MACRO
3964 The info macro command has new options `-all' and `--'. The first for
3965 printing all definitions of a macro. The second for explicitly specifying
3966 the end of arguments and the beginning of the macro name in case the macro
3967 name starts with a hyphen.
3969 collect[/s] EXPRESSIONS
3970 The tracepoint collect command now takes an optional modifier "/s"
3971 that directs it to dereference pointer-to-character types and
3972 collect the bytes of memory up to a zero byte. The behavior is
3973 similar to what you see when you use the regular print command on a
3974 string. An optional integer following the "/s" sets a bound on the
3975 number of bytes that will be collected.
3978 The trace start command now interprets any supplied arguments as a
3979 note to be recorded with the trace run, with an effect similar to
3980 setting the variable trace-notes.
3983 The trace stop command now interprets any arguments as a note to be
3984 mentioned along with the tstatus report that the trace was stopped
3985 with a command. The effect is similar to setting the variable
3988 * Tracepoints can now be enabled and disabled at any time after a trace
3989 experiment has been started using the standard "enable" and "disable"
3990 commands. It is now possible to start a trace experiment with no enabled
3991 tracepoints; GDB will display a warning, but will allow the experiment to
3992 begin, assuming that tracepoints will be enabled as needed while the trace
3995 * Fast tracepoints on 32-bit x86-architectures can now be placed at
3996 locations with 4-byte instructions, when they were previously
3997 limited to locations with instructions of 5 bytes or longer.
4001 set debug dwarf2-read
4002 show debug dwarf2-read
4003 Turns on or off display of debugging messages related to reading
4004 DWARF debug info. The default is off.
4006 set debug symtab-create
4007 show debug symtab-create
4008 Turns on or off display of debugging messages related to symbol table
4009 creation. The default is off.
4012 show extended-prompt
4013 Set the GDB prompt, and allow escape sequences to be inserted to
4014 display miscellaneous information (see 'help set extended-prompt'
4015 for the list of sequences). This prompt (and any information
4016 accessed through the escape sequences) is updated every time the
4017 prompt is displayed.
4019 set print entry-values (both|compact|default|if-needed|no|only|preferred)
4020 show print entry-values
4021 Set printing of frame argument values at function entry. In some cases
4022 GDB can determine the value of function argument which was passed by the
4023 function caller, even if the value was modified inside the called function.
4025 set debug entry-values
4026 show debug entry-values
4027 Control display of debugging info for determining frame argument values at
4028 function entry and virtual tail call frames.
4030 set basenames-may-differ
4031 show basenames-may-differ
4032 Set whether a source file may have multiple base names.
4033 (A "base name" is the name of a file with the directory part removed.
4034 Example: The base name of "/home/user/hello.c" is "hello.c".)
4035 If set, GDB will canonicalize file names (e.g., expand symlinks)
4036 before comparing them. Canonicalization is an expensive operation,
4037 but it allows the same file be known by more than one base name.
4038 If not set (the default), all source files are assumed to have just
4039 one base name, and gdb will do file name comparisons more efficiently.
4045 Set a user name and notes for the current and any future trace runs.
4046 This is useful for long-running and/or disconnected traces, to
4047 inform others (or yourself) as to who is running the trace, supply
4048 contact information, or otherwise explain what is going on.
4050 set trace-stop-notes
4051 show trace-stop-notes
4052 Set a note attached to the trace run, that is displayed when the
4053 trace has been stopped by a tstop command. This is useful for
4054 instance as an explanation, if you are stopping a trace run that was
4055 started by someone else.
4057 * New remote packets
4061 Dynamically enable a tracepoint in a started trace experiment.
4065 Dynamically disable a tracepoint in a started trace experiment.
4069 Set the user and notes of the trace run.
4073 Query the current status of a tracepoint.
4077 Query the minimum length of instruction at which a fast tracepoint may
4080 * Dcache size (number of lines) and line-size are now runtime-configurable
4081 via "set dcache line" and "set dcache line-size" commands.
4085 Texas Instruments TMS320C6x tic6x-*-*
4089 Renesas RL78 rl78-*-elf
4091 *** Changes in GDB 7.3.1
4093 * The build failure for NetBSD and OpenBSD targets have now been fixed.
4095 *** Changes in GDB 7.3
4097 * GDB has a new command: "thread find [REGEXP]".
4098 It finds the thread id whose name, target id, or thread extra info
4099 matches the given regular expression.
4101 * The "catch syscall" command now works on mips*-linux* targets.
4103 * The -data-disassemble MI command now supports modes 2 and 3 for
4104 dumping the instruction opcodes.
4106 * New command line options
4108 -data-directory DIR Specify DIR as the "data-directory".
4109 This is mostly for testing purposes.
4111 * The "maint set python auto-load on|off" command has been renamed to
4112 "set auto-load-scripts on|off".
4114 * GDB has a new command: "set directories".
4115 It is like the "dir" command except that it replaces the
4116 source path list instead of augmenting it.
4118 * GDB now understands thread names.
4120 On GNU/Linux, "info threads" will display the thread name as set by
4121 prctl or pthread_setname_np.
4123 There is also a new command, "thread name", which can be used to
4124 assign a name internally for GDB to display.
4127 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
4128 has been integrated into GDB.
4132 ** The function gdb.Write now accepts an optional keyword 'stream'.
4133 This keyword, when provided, will direct the output to either
4134 stdout, stderr, or GDB's logging output.
4136 ** Parameters can now be be sub-classed in Python, and in particular
4137 you may implement the get_set_doc and get_show_doc functions.
4138 This improves how Parameter set/show documentation is processed
4139 and allows for more dynamic content.
4141 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
4142 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
4143 have an is_valid method.
4145 ** Breakpoints can now be sub-classed in Python, and in particular
4146 you may implement a 'stop' function that is executed each time
4147 the inferior reaches that breakpoint.
4149 ** New function gdb.lookup_global_symbol looks up a global symbol.
4151 ** GDB values in Python are now callable if the value represents a
4152 function. For example, if 'some_value' represents a function that
4153 takes two integer parameters and returns a value, you can call
4154 that function like so:
4156 result = some_value (10,20)
4158 ** Module gdb.types has been added.
4159 It contains a collection of utilities for working with gdb.Types objects:
4160 get_basic_type, has_field, make_enum_dict.
4162 ** Module gdb.printing has been added.
4163 It contains utilities for writing and registering pretty-printers.
4164 New classes: PrettyPrinter, SubPrettyPrinter,
4165 RegexpCollectionPrettyPrinter.
4166 New function: register_pretty_printer.
4168 ** New commands "info pretty-printers", "enable pretty-printer" and
4169 "disable pretty-printer" have been added.
4171 ** gdb.parameter("directories") is now available.
4173 ** New function gdb.newest_frame returns the newest frame in the
4176 ** The gdb.InferiorThread class has a new "name" attribute. This
4177 holds the thread's name.
4179 ** Python Support for Inferior events.
4180 Python scripts can add observers to be notified of events
4181 occurring in the process being debugged.
4182 The following events are currently supported:
4183 - gdb.events.cont Continue event.
4184 - gdb.events.exited Inferior exited event.
4185 - gdb.events.stop Signal received, and Breakpoint hit events.
4189 ** GDB now puts template parameters in scope when debugging in an
4190 instantiation. For example, if you have:
4192 template<int X> int func (void) { return X; }
4194 then if you step into func<5>, "print X" will show "5". This
4195 feature requires proper debuginfo support from the compiler; it
4196 was added to GCC 4.5.
4198 ** The motion commands "next", "finish", "until", and "advance" now
4199 work better when exceptions are thrown. In particular, GDB will
4200 no longer lose control of the inferior; instead, the GDB will
4201 stop the inferior at the point at which the exception is caught.
4202 This functionality requires a change in the exception handling
4203 code that was introduced in GCC 4.5.
4205 * GDB now follows GCC's rules on accessing volatile objects when
4206 reading or writing target state during expression evaluation.
4207 One notable difference to prior behavior is that "print x = 0"
4208 no longer generates a read of x; the value of the assignment is
4209 now always taken directly from the value being assigned.
4211 * GDB now has some support for using labels in the program's source in
4212 linespecs. For instance, you can use "advance label" to continue
4213 execution to a label.
4215 * GDB now has support for reading and writing a new .gdb_index
4216 section. This section holds a fast index of DWARF debugging
4217 information and can be used to greatly speed up GDB startup and
4218 operation. See the documentation for `save gdb-index' for details.
4220 * The "watch" command now accepts an optional "-location" argument.
4221 When used, this causes GDB to watch the memory referred to by the
4222 expression. Such a watchpoint is never deleted due to it going out
4225 * GDB now supports thread debugging of core dumps on GNU/Linux.
4227 GDB now activates thread debugging using the libthread_db library
4228 when debugging GNU/Linux core dumps, similarly to when debugging
4229 live processes. As a result, when debugging a core dump file, GDB
4230 is now able to display pthread_t ids of threads. For example, "info
4231 threads" shows the same output as when debugging the process when it
4232 was live. In earlier releases, you'd see something like this:
4235 * 1 LWP 6780 main () at main.c:10
4237 While now you see this:
4240 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
4242 It is also now possible to inspect TLS variables when debugging core
4245 When debugging a core dump generated on a machine other than the one
4246 used to run GDB, you may need to point GDB at the correct
4247 libthread_db library with the "set libthread-db-search-path"
4248 command. See the user manual for more details on this command.
4250 * When natively debugging programs on PowerPC BookE processors running
4251 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
4252 which stop execution of the inferior whenever it executes an instruction
4253 at any address within the specified range. See the "PowerPC Embedded"
4254 section in the user manual for more details.
4256 * New features in the GDB remote stub, GDBserver
4258 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
4259 and i686 LynxOS (version 5.x).
4261 ** GDBserver is now supported on Blackfin Linux.
4263 * New native configurations
4265 ia64 HP-UX ia64-*-hpux*
4269 Analog Devices, Inc. Blackfin Processor bfin-*
4271 * Ada task switching is now supported on sparc-elf targets when
4272 debugging a program using the Ravenscar Profile. For more information,
4273 see the "Tasking Support when using the Ravenscar Profile" section
4274 in the GDB user manual.
4276 * Guile support was removed.
4278 * New features in the GNU simulator
4280 ** The --map-info flag lists all known core mappings.
4282 ** CFI flashes may be simulated via the "cfi" device.
4284 *** Changes in GDB 7.2
4286 * Shared library support for remote targets by default
4288 When GDB is configured for a generic, non-OS specific target, like
4289 for example, --target=arm-eabi or one of the many *-*-elf targets,
4290 GDB now queries remote stubs for loaded shared libraries using the
4291 `qXfer:libraries:read' packet. Previously, shared library support
4292 was always disabled for such configurations.
4296 ** Argument Dependent Lookup (ADL)
4298 In C++ ADL lookup directs function search to the namespaces of its
4299 arguments even if the namespace has not been imported.
4309 Here the compiler will search for `foo' in the namespace of 'b'
4310 and find A::foo. GDB now supports this. This construct is commonly
4311 used in the Standard Template Library for operators.
4313 ** Improved User Defined Operator Support
4315 In addition to member operators, GDB now supports lookup of operators
4316 defined in a namespace and imported with a `using' directive, operators
4317 defined in the global scope, operators imported implicitly from an
4318 anonymous namespace, and the ADL operators mentioned in the previous
4320 GDB now also supports proper overload resolution for all the previously
4321 mentioned flavors of operators.
4323 ** static const class members
4325 Printing of static const class members that are initialized in the
4326 class definition has been fixed.
4328 * Windows Thread Information Block access.
4330 On Windows targets, GDB now supports displaying the Windows Thread
4331 Information Block (TIB) structure. This structure is visible either
4332 by using the new command `info w32 thread-information-block' or, by
4333 dereferencing the new convenience variable named `$_tlb', a
4334 thread-specific pointer to the TIB. This feature is also supported
4335 when remote debugging using GDBserver.
4337 * Static tracepoints
4339 Static tracepoints are calls in the user program into a tracing
4340 library. One such library is a port of the LTTng kernel tracer to
4341 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
4342 When debugging with GDBserver, GDB now supports combining the GDB
4343 tracepoint machinery with such libraries. For example: the user can
4344 use GDB to probe a static tracepoint marker (a call from the user
4345 program into the tracing library) with the new "strace" command (see
4346 "New commands" below). This creates a "static tracepoint" in the
4347 breakpoint list, that can be manipulated with the same feature set
4348 as fast and regular tracepoints. E.g., collect registers, local and
4349 global variables, collect trace state variables, and define
4350 tracepoint conditions. In addition, the user can collect extra
4351 static tracepoint marker specific data, by collecting the new
4352 $_sdata internal variable. When analyzing the trace buffer, you can
4353 inspect $_sdata like any other variable available to GDB. For more
4354 information, see the "Tracepoints" chapter in GDB user manual. New
4355 remote packets have been defined to support static tracepoints, see
4356 the "New remote packets" section below.
4358 * Better reconstruction of tracepoints after disconnected tracing
4360 GDB will attempt to download the original source form of tracepoint
4361 definitions when starting a trace run, and then will upload these
4362 upon reconnection to the target, resulting in a more accurate
4363 reconstruction of the tracepoints that are in use on the target.
4367 You can now exercise direct control over the ways that GDB can
4368 affect your program. For instance, you can disallow the setting of
4369 breakpoints, so that the program can run continuously (assuming
4370 non-stop mode). In addition, the "observer" variable is available
4371 to switch all of the different controls; in observer mode, GDB
4372 cannot affect the target's behavior at all, which is useful for
4373 tasks like diagnosing live systems in the field.
4375 * The new convenience variable $_thread holds the number of the
4378 * New remote packets
4382 Return the address of the Windows Thread Information Block of a given thread.
4386 In response to several of the tracepoint packets, the target may now
4387 also respond with a number of intermediate `qRelocInsn' request
4388 packets before the final result packet, to have GDB handle
4389 relocating an instruction to execute at a different address. This
4390 is particularly useful for stubs that support fast tracepoints. GDB
4391 reports support for this feature in the qSupported packet.
4395 List static tracepoint markers in the target program.
4399 List static tracepoint markers at a given address in the target
4402 qXfer:statictrace:read
4404 Read the static trace data collected (by a `collect $_sdata'
4405 tracepoint action). The remote stub reports support for this packet
4406 to gdb's qSupported query.
4410 Send the current settings of GDB's permission flags.
4414 Send part of the source (textual) form of a tracepoint definition,
4415 which includes location, conditional, and action list.
4417 * The source command now accepts a -s option to force searching for the
4418 script in the source search path even if the script name specifies
4421 * New features in the GDB remote stub, GDBserver
4423 - GDBserver now support tracepoints (including fast tracepoints, and
4424 static tracepoints). The feature is currently supported by the
4425 i386-linux and amd64-linux builds. See the "Tracepoints support
4426 in gdbserver" section in the manual for more information.
4428 GDBserver JIT compiles the tracepoint's conditional agent
4429 expression bytecode into native code whenever possible for low
4430 overhead dynamic tracepoints conditionals. For such tracepoints,
4431 an expression that examines program state is evaluated when the
4432 tracepoint is reached, in order to determine whether to capture
4433 trace data. If the condition is simple and false, processing the
4434 tracepoint finishes very quickly and no data is gathered.
4436 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
4437 for static tracepoints support.
4439 - GDBserver now supports x86_64 Windows 64-bit debugging.
4441 * GDB now sends xmlRegisters= in qSupported packet to indicate that
4442 it understands register description.
4444 * The --batch flag now disables pagination and queries.
4446 * X86 general purpose registers
4448 GDB now supports reading/writing byte, word and double-word x86
4449 general purpose registers directly. This means you can use, say,
4450 $ah or $ax to refer, respectively, to the byte register AH and
4451 16-bit word register AX that are actually portions of the 32-bit
4452 register EAX or 64-bit register RAX.
4454 * The `commands' command now accepts a range of breakpoints to modify.
4455 A plain `commands' following a command that creates multiple
4456 breakpoints affects all the breakpoints set by that command. This
4457 applies to breakpoints set by `rbreak', and also applies when a
4458 single `break' command creates multiple breakpoints (e.g.,
4459 breakpoints on overloaded c++ functions).
4461 * The `rbreak' command now accepts a filename specification as part of
4462 its argument, limiting the functions selected by the regex to those
4463 in the specified file.
4465 * Support for remote debugging Windows and SymbianOS shared libraries
4466 from Unix hosts has been improved. Non Windows GDB builds now can
4467 understand target reported file names that follow MS-DOS based file
4468 system semantics, such as file names that include drive letters and
4469 use the backslash character as directory separator. This makes it
4470 possible to transparently use the "set sysroot" and "set
4471 solib-search-path" on Unix hosts to point as host copies of the
4472 target's shared libraries. See the new command "set
4473 target-file-system-kind" described below, and the "Commands to
4474 specify files" section in the user manual for more information.
4478 eval template, expressions...
4479 Convert the values of one or more expressions under the control
4480 of the string template to a command line, and call it.
4482 set target-file-system-kind unix|dos-based|auto
4483 show target-file-system-kind
4484 Set or show the assumed file system kind for target reported file
4487 save breakpoints <filename>
4488 Save all current breakpoint definitions to a file suitable for use
4489 in a later debugging session. To read the saved breakpoint
4490 definitions, use the `source' command.
4492 `save tracepoints' is a new alias for `save-tracepoints'. The latter
4495 info static-tracepoint-markers
4496 Display information about static tracepoint markers in the target.
4498 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
4499 Define a static tracepoint by probing a marker at the given
4500 function, line, address, or marker ID.
4504 Enable and disable observer mode.
4506 set may-write-registers on|off
4507 set may-write-memory on|off
4508 set may-insert-breakpoints on|off
4509 set may-insert-tracepoints on|off
4510 set may-insert-fast-tracepoints on|off
4511 set may-interrupt on|off
4512 Set individual permissions for GDB effects on the target. Note that
4513 some of these settings can have undesirable or surprising
4514 consequences, particularly when changed in the middle of a session.
4515 For instance, disabling the writing of memory can prevent
4516 breakpoints from being inserted, cause single-stepping to fail, or
4517 even crash your program, if you disable after breakpoints have been
4518 inserted. However, GDB should not crash.
4520 set record memory-query on|off
4521 show record memory-query
4522 Control whether to stop the inferior if memory changes caused
4523 by an instruction cannot be recorded.
4528 The disassemble command now supports "start,+length" form of two arguments.
4532 ** GDB now provides a new directory location, called the python directory,
4533 where Python scripts written for GDB can be installed. The location
4534 of that directory is <data-directory>/python, where <data-directory>
4535 is the GDB data directory. For more details, see section `Scripting
4536 GDB using Python' in the manual.
4538 ** The GDB Python API now has access to breakpoints, symbols, symbol
4539 tables, program spaces, inferiors, threads and frame's code blocks.
4540 Additionally, GDB Parameters can now be created from the API, and
4541 manipulated via set/show in the CLI.
4543 ** New functions gdb.target_charset, gdb.target_wide_charset,
4544 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
4546 ** New exception gdb.GdbError.
4548 ** Pretty-printers are now also looked up in the current program space.
4550 ** Pretty-printers can now be individually enabled and disabled.
4552 ** GDB now looks for names of Python scripts to auto-load in a
4553 special section named `.debug_gdb_scripts', in addition to looking
4554 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
4556 * Tracepoint actions were unified with breakpoint commands. In particular,
4557 there are no longer differences in "info break" output for breakpoints and
4558 tracepoints and the "commands" command can be used for both tracepoints and
4559 regular breakpoints.
4563 ARM Symbian arm*-*-symbianelf*
4565 * D language support.
4566 GDB now supports debugging programs written in the D programming
4569 * GDB now supports the extended ptrace interface for PowerPC which is
4570 available since Linux kernel version 2.6.34. This automatically enables
4571 any hardware breakpoints and additional hardware watchpoints available in
4572 the processor. The old ptrace interface exposes just one hardware
4573 watchpoint and no hardware breakpoints.
4575 * GDB is now able to use the Data Value Compare (DVC) register available on
4576 embedded PowerPC processors to implement in hardware simple watchpoint
4577 conditions of the form:
4579 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
4581 This works in native GDB running on Linux kernels with the extended ptrace
4582 interface mentioned above.
4584 *** Changes in GDB 7.1
4588 ** Namespace Support
4590 GDB now supports importing of namespaces in C++. This enables the
4591 user to inspect variables from imported namespaces. Support for
4592 namepace aliasing has also been added. So, if a namespace is
4593 aliased in the current scope (e.g. namepace C=A; ) the user can
4594 print variables using the alias (e.g. (gdb) print C::x).
4598 All known bugs relating to the printing of virtual base class were
4599 fixed. It is now possible to call overloaded static methods using a
4604 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
4605 and reinterpret_cast<> are now handled by the C++ expression parser.
4609 Xilinx MicroBlaze microblaze-*-*
4614 Xilinx MicroBlaze microblaze
4617 * Multi-program debugging.
4619 GDB now has support for multi-program (a.k.a. multi-executable or
4620 multi-exec) debugging. This allows for debugging multiple inferiors
4621 simultaneously each running a different program under the same GDB
4622 session. See "Debugging Multiple Inferiors and Programs" in the
4623 manual for more information. This implied some user visible changes
4624 in the multi-inferior support. For example, "info inferiors" now
4625 lists inferiors that are not running yet or that have exited
4626 already. See also "New commands" and "New options" below.
4628 * New tracing features
4630 GDB's tracepoint facility now includes several new features:
4632 ** Trace state variables
4634 GDB tracepoints now include support for trace state variables, which
4635 are variables managed by the target agent during a tracing
4636 experiment. They are useful for tracepoints that trigger each
4637 other, so for instance one tracepoint can count hits in a variable,
4638 and then a second tracepoint has a condition that is true when the
4639 count reaches a particular value. Trace state variables share the
4640 $-syntax of GDB convenience variables, and can appear in both
4641 tracepoint actions and condition expressions. Use the "tvariable"
4642 command to create, and "info tvariables" to view; see "Trace State
4643 Variables" in the manual for more detail.
4647 GDB now includes an option for defining fast tracepoints, which
4648 targets may implement more efficiently, such as by installing a jump
4649 into the target agent rather than a trap instruction. The resulting
4650 speedup can be by two orders of magnitude or more, although the
4651 tradeoff is that some program locations on some target architectures
4652 might not allow fast tracepoint installation, for instance if the
4653 instruction to be replaced is shorter than the jump. To request a
4654 fast tracepoint, use the "ftrace" command, with syntax identical to
4655 the regular trace command.
4657 ** Disconnected tracing
4659 It is now possible to detach GDB from the target while it is running
4660 a trace experiment, then reconnect later to see how the experiment
4661 is going. In addition, a new variable disconnected-tracing lets you
4662 tell the target agent whether to continue running a trace if the
4663 connection is lost unexpectedly.
4667 GDB now has the ability to save the trace buffer into a file, and
4668 then use that file as a target, similarly to you can do with
4669 corefiles. You can select trace frames, print data that was
4670 collected in them, and use tstatus to display the state of the
4671 tracing run at the moment that it was saved. To create a trace
4672 file, use "tsave <filename>", and to use it, do "target tfile
4675 ** Circular trace buffer
4677 You can ask the target agent to handle the trace buffer as a
4678 circular buffer, discarding the oldest trace frames to make room for
4679 newer ones, by setting circular-trace-buffer to on. This feature may
4680 not be available for all target agents.
4685 The disassemble command, when invoked with two arguments, now requires
4686 the arguments to be comma-separated.
4689 The info variables command now displays variable definitions. Files
4690 which only declare a variable are not shown.
4693 The source command is now capable of sourcing Python scripts.
4694 This feature is dependent on the debugger being build with Python
4697 Related to this enhancement is also the introduction of a new command
4698 "set script-extension" (see below).
4700 * New commands (for set/show, see "New options" below)
4702 record save [<FILENAME>]
4703 Save a file (in core file format) containing the process record
4704 execution log for replay debugging at a later time.
4706 record restore <FILENAME>
4707 Restore the process record execution log that was saved at an
4708 earlier time, for replay debugging.
4710 add-inferior [-copies <N>] [-exec <FILENAME>]
4713 clone-inferior [-copies <N>] [ID]
4714 Make a new inferior ready to execute the same program another
4715 inferior has loaded.
4720 maint info program-spaces
4721 List the program spaces loaded into GDB.
4723 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
4724 show remote interrupt-sequence
4725 Allow the user to select one of ^C, a BREAK signal or BREAK-g
4726 as the sequence to the remote target in order to interrupt the execution.
4727 Ctrl-C is a default. Some system prefers BREAK which is high level of
4728 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
4729 Magic SysRq g. It is BREAK signal and character 'g'.
4731 set remote interrupt-on-connect [on | off]
4732 show remote interrupt-on-connect
4733 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
4734 remote target when gdb connects to it. This is needed when you debug
4737 set remotebreak [on | off]
4739 Deprecated. Use "set/show remote interrupt-sequence" instead.
4741 tvariable $NAME [ = EXP ]
4742 Create or modify a trace state variable.
4745 List trace state variables and their values.
4747 delete tvariable $NAME ...
4748 Delete one or more trace state variables.
4751 Evaluate the given expressions without collecting anything into the
4752 trace buffer. (Valid in tracepoint actions only.)
4754 ftrace FN / FILE:LINE / *ADDR
4755 Define a fast tracepoint at the given function, line, or address.
4757 * New expression syntax
4759 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
4760 GDB now parses 0b101010 identically with 42.
4764 set follow-exec-mode new|same
4765 show follow-exec-mode
4766 Control whether GDB reuses the same inferior across an exec call or
4767 creates a new one. This is useful to be able to restart the old
4768 executable after the inferior having done an exec call.
4770 set default-collect EXPR, ...
4771 show default-collect
4772 Define a list of expressions to be collected at each tracepoint.
4773 This is a useful way to ensure essential items are not overlooked,
4774 such as registers or a critical global variable.
4776 set disconnected-tracing
4777 show disconnected-tracing
4778 If set to 1, the target is instructed to continue tracing if it
4779 loses its connection to GDB. If 0, the target is to stop tracing
4782 set circular-trace-buffer
4783 show circular-trace-buffer
4784 If set to on, the target is instructed to use a circular trace buffer
4785 and discard the oldest trace frames instead of stopping the trace due
4786 to a full trace buffer. If set to off, the trace stops when the buffer
4787 fills up. Some targets may not support this.
4789 set script-extension off|soft|strict
4790 show script-extension
4791 If set to "off", the debugger does not perform any script language
4792 recognition, and all sourced files are assumed to be GDB scripts.
4793 If set to "soft" (the default), files are sourced according to
4794 filename extension, falling back to GDB scripts if the first
4796 If set to "strict", files are sourced according to filename extension.
4798 set ada trust-PAD-over-XVS on|off
4799 show ada trust-PAD-over-XVS
4800 If off, activate a workaround against a bug in the debugging information
4801 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
4802 the GCC sources for more information about the GNAT encoding and
4803 PAD types in particular). It is always safe to set this option to
4804 off, but this introduces a slight performance penalty. The default
4807 * Python API Improvements
4809 ** GDB provides the new class gdb.LazyString. This is useful in
4810 some pretty-printing cases. The new method gdb.Value.lazy_string
4811 provides a simple way to create objects of this type.
4813 ** The fields returned by gdb.Type.fields now have an
4814 `is_base_class' attribute.
4816 ** The new method gdb.Type.range returns the range of an array type.
4818 ** The new method gdb.parse_and_eval can be used to parse and
4819 evaluate an expression.
4821 * New remote packets
4824 Define a trace state variable.
4827 Get the current value of a trace state variable.
4830 Set desired tracing behavior upon disconnection.
4833 Set the trace buffer to be linear or circular.
4836 Get data about the tracepoints currently in use.
4840 Process record now works correctly with hardware watchpoints.
4842 Multiple bug fixes have been made to the mips-irix port, making it
4843 much more reliable. In particular:
4844 - Debugging threaded applications is now possible again. Previously,
4845 GDB would hang while starting the program, or while waiting for
4846 the program to stop at a breakpoint.
4847 - Attaching to a running process no longer hangs.
4848 - An error occurring while loading a core file has been fixed.
4849 - Changing the value of the PC register now works again. This fixes
4850 problems observed when using the "jump" command, or when calling
4851 a function from GDB, or even when assigning a new value to $pc.
4852 - With the "finish" and "return" commands, the return value for functions
4853 returning a small array is now correctly printed.
4854 - It is now possible to break on shared library code which gets executed
4855 during a shared library init phase (code executed while executing
4856 their .init section). Previously, the breakpoint would have no effect.
4857 - GDB is now able to backtrace through the signal handler for
4858 non-threaded programs.
4860 PIE (Position Independent Executable) programs debugging is now supported.
4861 This includes debugging execution of PIC (Position Independent Code) shared
4862 libraries although for that, it should be possible to run such libraries as an
4865 *** Changes in GDB 7.0
4867 * GDB now has an interface for JIT compilation. Applications that
4868 dynamically generate code can create symbol files in memory and register
4869 them with GDB. For users, the feature should work transparently, and
4870 for JIT developers, the interface is documented in the GDB manual in the
4871 "JIT Compilation Interface" chapter.
4873 * Tracepoints may now be conditional. The syntax is as for
4874 breakpoints; either an "if" clause appended to the "trace" command,
4875 or the "condition" command is available. GDB sends the condition to
4876 the target for evaluation using the same bytecode format as is used
4877 for tracepoint actions.
4879 * The disassemble command now supports: an optional /r modifier, print the
4880 raw instructions in hex as well as in symbolic form, and an optional /m
4881 modifier to print mixed source+assembly.
4883 * Process record and replay
4885 In a architecture environment that supports ``process record and
4886 replay'', ``process record and replay'' target can record a log of
4887 the process execution, and replay it with both forward and reverse
4890 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
4891 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
4892 set execution-direction {forward|reverse}, for targets that support
4895 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
4896 feature is available with a native GDB running on kernel version
4899 * GDB now has support for multi-byte and wide character sets on the
4900 target. Strings whose character type is wchar_t, char16_t, or
4901 char32_t are now correctly printed. GDB supports wide- and unicode-
4902 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
4903 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
4904 `printf'. This feature requires iconv to work properly; if your
4905 system does not have a working iconv, GDB can use GNU libiconv. See
4906 the installation instructions for more information.
4908 * GDB now supports automatic retrieval of shared library files from
4909 remote targets. To use this feature, specify a system root that begins
4910 with the `remote:' prefix, either via the `set sysroot' command or via
4911 the `--with-sysroot' configure-time option.
4913 * "info sharedlibrary" now takes an optional regex of libraries to show,
4914 and it now reports if a shared library has no debugging information.
4916 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
4917 now complete on file names.
4919 * When completing in expressions, gdb will attempt to limit
4920 completions to allowable structure or union fields, where appropriate.
4921 For instance, consider:
4923 # struct example { int f1; double f2; };
4924 # struct example variable;
4927 If the user types TAB at the end of this command line, the available
4928 completions will be "f1" and "f2".
4930 * Inlined functions are now supported. They show up in backtraces, and
4931 the "step", "next", and "finish" commands handle them automatically.
4933 * GDB now supports the token-splicing (##) and stringification (#)
4934 operators when expanding macros. It also supports variable-arity
4937 * GDB now supports inspecting extra signal information, exported by
4938 the new $_siginfo convenience variable. The feature is currently
4939 implemented on linux ARM, i386 and amd64.
4941 * GDB can now display the VFP floating point registers and NEON vector
4942 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
4943 can provide these registers (requires Linux 2.6.30 or later). Remote
4944 and simulator targets may also provide them.
4946 * New remote packets
4949 Search memory for a sequence of bytes.
4952 Turn off `+'/`-' protocol acknowledgments to permit more efficient
4953 operation over reliable transport links. Use of this packet is
4954 controlled by the `set remote noack-packet' command.
4957 Kill the process with the specified process ID. Use this in preference
4958 to `k' when multiprocess protocol extensions are supported.
4961 Obtains additional operating system information
4965 Read or write additional signal information.
4967 * Removed remote protocol undocumented extension
4969 An undocumented extension to the remote protocol's `S' stop reply
4970 packet that permitted the stub to pass a process id was removed.
4971 Remote servers should use the `T' stop reply packet instead.
4973 * GDB now supports multiple function calling conventions according to the
4974 DWARF-2 DW_AT_calling_convention function attribute.
4976 * The SH target utilizes the aforementioned change to distinguish between gcc
4977 and Renesas calling convention. It also adds the new CLI commands
4978 `set/show sh calling-convention'.
4980 * GDB can now read compressed debug sections, as produced by GNU gold
4981 with the --compress-debug-sections=zlib flag.
4983 * 64-bit core files are now supported on AIX.
4985 * Thread switching is now supported on Tru64.
4987 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
4988 which will be allocated using malloc later in program execution.
4990 * The qXfer:libraries:read remote protocol packet now allows passing a
4991 list of section offsets.
4993 * On GNU/Linux, GDB can now attach to stopped processes. Several race
4994 conditions handling signals delivered during attach or thread creation
4995 have also been fixed.
4997 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
4998 From the user's standpoint, all unqualified instances of True and False
4999 are treated as the standard definitions, regardless of context.
5001 * GDB now parses C++ symbol and type names more flexibly. For
5004 template<typename T> class C { };
5007 GDB will now correctly handle all of:
5009 ptype C<char const *>
5010 ptype C<char const*>
5011 ptype C<const char *>
5012 ptype C<const char*>
5014 * New features in the GDB remote stub, gdbserver
5016 - The "--wrapper" command-line argument tells gdbserver to use a
5017 wrapper program to launch programs for debugging.
5019 - On PowerPC and S/390 targets, it is now possible to use a single
5020 gdbserver executable to debug both 32-bit and 64-bit programs.
5021 (This requires gdbserver itself to be built as a 64-bit executable.)
5023 - gdbserver uses the new noack protocol mode for TCP connections to
5024 reduce communications latency, if also supported and enabled in GDB.
5026 - Support for the sparc64-linux-gnu target is now included in
5029 - The amd64-linux build of gdbserver now supports debugging both
5030 32-bit and 64-bit programs.
5032 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
5033 now support hardware watchpoints, and will use them automatically
5038 GDB now has support for scripting using Python. Whether this is
5039 available is determined at configure time.
5041 New GDB commands can now be written in Python.
5043 * Ada tasking support
5045 Ada tasks can now be inspected in GDB. The following commands have
5049 Print the list of Ada tasks.
5051 Print detailed information about task number N.
5053 Print the task number of the current task.
5055 Switch the context of debugging to task number N.
5057 * Support for user-defined prefixed commands. The "define" command can
5058 add new commands to existing prefixes, e.g. "target".
5060 * Multi-inferior, multi-process debugging.
5062 GDB now has generalized support for multi-inferior debugging. See
5063 "Debugging Multiple Inferiors" in the manual for more information.
5064 Although availability still depends on target support, the command
5065 set is more uniform now. The GNU/Linux specific multi-forks support
5066 has been migrated to this new framework. This implied some user
5067 visible changes; see "New commands" and also "Removed commands"
5070 * Target descriptions can now describe the target OS ABI. See the
5071 "Target Description Format" section in the user manual for more
5074 * Target descriptions can now describe "compatible" architectures
5075 to indicate that the target can execute applications for a different
5076 architecture in addition to those for the main target architecture.
5077 See the "Target Description Format" section in the user manual for
5080 * Multi-architecture debugging.
5082 GDB now includes general supports for debugging applications on
5083 hybrid systems that use more than one single processor architecture
5084 at the same time. Each such hybrid architecture still requires
5085 specific support to be added. The only hybrid architecture supported
5086 in this version of GDB is the Cell Broadband Engine.
5088 * GDB now supports integrated debugging of Cell/B.E. applications that
5089 use both the PPU and SPU architectures. To enable support for hybrid
5090 Cell/B.E. debugging, you need to configure GDB to support both the
5091 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
5092 --enable-targets configure option.
5094 * Non-stop mode debugging.
5096 For some targets, GDB now supports an optional mode of operation in
5097 which you can examine stopped threads while other threads continue
5098 to execute freely. This is referred to as non-stop mode, with the
5099 old mode referred to as all-stop mode. See the "Non-Stop Mode"
5100 section in the user manual for more information.
5102 To be able to support remote non-stop debugging, a remote stub needs
5103 to implement the non-stop mode remote protocol extensions, as
5104 described in the "Remote Non-Stop" section of the user manual. The
5105 GDB remote stub, gdbserver, has been adjusted to support these
5106 extensions on linux targets.
5108 * New commands (for set/show, see "New options" below)
5110 catch syscall [NAME(S) | NUMBER(S)]
5111 Catch system calls. Arguments, which should be names of system
5112 calls or their numbers, mean catch only those syscalls. Without
5113 arguments, every syscall will be caught. When the inferior issues
5114 any of the specified syscalls, GDB will stop and announce the system
5115 call, both when it is called and when its call returns. This
5116 feature is currently available with a native GDB running on the
5117 Linux Kernel, under the following architectures: x86, x86_64,
5118 PowerPC and PowerPC64.
5120 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
5122 Search memory for a sequence of bytes.
5124 maint set python print-stack
5125 maint show python print-stack
5126 Show a stack trace when an error is encountered in a Python script.
5129 Invoke CODE by passing it to the Python interpreter.
5134 These allow macros to be defined, undefined, and listed
5138 Show operating system information about processes.
5141 List the inferiors currently under GDB's control.
5144 Switch focus to inferior number NUM.
5147 Detach from inferior number NUM.
5150 Kill inferior number NUM.
5154 set spu stop-on-load
5155 show spu stop-on-load
5156 Control whether to stop for new SPE threads during Cell/B.E. debugging.
5158 set spu auto-flush-cache
5159 show spu auto-flush-cache
5160 Control whether to automatically flush the software-managed cache
5161 during Cell/B.E. debugging.
5163 set sh calling-convention
5164 show sh calling-convention
5165 Control the calling convention used when calling SH target functions.
5168 show debug timestamp
5169 Control display of timestamps with GDB debugging output.
5171 set disassemble-next-line
5172 show disassemble-next-line
5173 Control display of disassembled source lines or instructions when
5176 set remote noack-packet
5177 show remote noack-packet
5178 Set/show the use of remote protocol QStartNoAckMode packet. See above
5179 under "New remote packets."
5181 set remote query-attached-packet
5182 show remote query-attached-packet
5183 Control use of remote protocol `qAttached' (query-attached) packet.
5185 set remote read-siginfo-object
5186 show remote read-siginfo-object
5187 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
5190 set remote write-siginfo-object
5191 show remote write-siginfo-object
5192 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
5195 set remote reverse-continue
5196 show remote reverse-continue
5197 Control use of remote protocol 'bc' (reverse-continue) packet.
5199 set remote reverse-step
5200 show remote reverse-step
5201 Control use of remote protocol 'bs' (reverse-step) packet.
5203 set displaced-stepping
5204 show displaced-stepping
5205 Control displaced stepping mode. Displaced stepping is a way to
5206 single-step over breakpoints without removing them from the debuggee.
5207 Also known as "out-of-line single-stepping".
5210 show debug displaced
5211 Control display of debugging info for displaced stepping.
5213 maint set internal-error
5214 maint show internal-error
5215 Control what GDB does when an internal error is detected.
5217 maint set internal-warning
5218 maint show internal-warning
5219 Control what GDB does when an internal warning is detected.
5224 Use a wrapper program to launch programs for debugging.
5226 set multiple-symbols (all|ask|cancel)
5227 show multiple-symbols
5228 The value of this variable can be changed to adjust the debugger behavior
5229 when an expression or a breakpoint location contains an ambiguous symbol
5230 name (an overloaded function name, for instance).
5232 set breakpoint always-inserted
5233 show breakpoint always-inserted
5234 Keep breakpoints always inserted in the target, as opposed to inserting
5235 them when resuming the target, and removing them when the target stops.
5236 This option can improve debugger performance on slow remote targets.
5238 set arm fallback-mode (arm|thumb|auto)
5239 show arm fallback-mode
5240 set arm force-mode (arm|thumb|auto)
5242 These commands control how ARM GDB determines whether instructions
5243 are ARM or Thumb. The default for both settings is auto, which uses
5244 the current CPSR value for instructions without symbols; previous
5245 versions of GDB behaved as if "set arm fallback-mode arm".
5247 set arm unwind-secure-frames
5248 Enable unwinding from Non-secure to Secure mode on Cortex-M with
5250 This can trigger security exceptions when unwinding exception stacks.
5252 set disable-randomization
5253 show disable-randomization
5254 Standalone programs run with the virtual address space randomization enabled
5255 by default on some platforms. This option keeps the addresses stable across
5256 multiple debugging sessions.
5260 Control whether other threads are stopped or not when some thread hits
5265 Requests that asynchronous execution is enabled in the target, if available.
5266 In this case, it's possible to resume target in the background, and interact
5267 with GDB while the target is running. "show target-async" displays the
5268 current state of asynchronous execution of the target.
5270 set target-wide-charset
5271 show target-wide-charset
5272 The target-wide-charset is the name of the character set that GDB
5273 uses when printing characters whose type is wchar_t.
5275 set tcp auto-retry (on|off)
5277 set tcp connect-timeout
5278 show tcp connect-timeout
5279 These commands allow GDB to retry failed TCP connections to a remote stub
5280 with a specified timeout period; this is useful if the stub is launched
5281 in parallel with GDB but may not be ready to accept connections immediately.
5283 set libthread-db-search-path
5284 show libthread-db-search-path
5285 Control list of directories which GDB will search for appropriate
5288 set schedule-multiple (on|off)
5289 show schedule-multiple
5290 Allow GDB to resume all threads of all processes or only threads of
5291 the current process.
5295 Use more aggressive caching for accesses to the stack. This improves
5296 performance of remote debugging (particularly backtraces) without
5297 affecting correctness.
5299 set interactive-mode (on|off|auto)
5300 show interactive-mode
5301 Control whether GDB runs in interactive mode (on) or not (off).
5302 When in interactive mode, GDB waits for the user to answer all
5303 queries. Otherwise, GDB does not wait and assumes the default
5304 answer. When set to auto (the default), GDB determines which
5305 mode to use based on the stdin settings.
5310 For program forks, this is replaced by the new more generic `info
5311 inferiors' command. To list checkpoints, you can still use the
5312 `info checkpoints' command, which was an alias for the `info forks'
5316 Replaced by the new `inferior' command. To switch between
5317 checkpoints, you can still use the `restart' command, which was an
5318 alias for the `fork' command.
5321 This is removed, since some targets don't have a notion of
5322 processes. To switch between processes, you can still use the
5323 `inferior' command using GDB's own inferior number.
5326 For program forks, this is replaced by the new more generic `kill
5327 inferior' command. To delete a checkpoint, you can still use the
5328 `delete checkpoint' command, which was an alias for the `delete
5332 For program forks, this is replaced by the new more generic `detach
5333 inferior' command. To detach a checkpoint, you can still use the
5334 `detach checkpoint' command, which was an alias for the `detach
5337 * New native configurations
5339 x86/x86_64 Darwin i[34567]86-*-darwin*
5341 x86_64 MinGW x86_64-*-mingw*
5345 Lattice Mico32 lm32-*
5346 x86 DICOS i[34567]86-*-dicos*
5347 x86_64 DICOS x86_64-*-dicos*
5350 * The GDB remote stub, gdbserver, now supports x86 Windows CE
5351 (mingw32ce) debugging.
5357 These commands were actually not implemented on any target.
5359 *** Changes in GDB 6.8
5361 * New native configurations
5363 NetBSD/hppa hppa*-*netbsd*
5364 Xtensa GNU/Linux xtensa*-*-linux*
5368 NetBSD/hppa hppa*-*-netbsd*
5369 Xtensa GNU/Linux xtensa*-*-linux*
5371 * Change in command line behavior -- corefiles vs. process ids.
5373 When the '-p NUMBER' or '--pid NUMBER' options are used, and
5374 attaching to process NUMBER fails, GDB no longer attempts to open a
5375 core file named NUMBER. Attaching to a program using the -c option
5376 is no longer supported. Instead, use the '-p' or '--pid' options.
5378 * GDB can now be built as a native debugger for debugging Windows x86
5379 (mingw32) Portable Executable (PE) programs.
5381 * Pending breakpoints no longer change their number when their address
5384 * GDB now supports breakpoints with multiple locations,
5385 including breakpoints on C++ constructors, inside C++ templates,
5386 and in inlined functions.
5388 * GDB's ability to debug optimized code has been improved. GDB more
5389 accurately identifies function bodies and lexical blocks that occupy
5390 more than one contiguous range of addresses.
5392 * Target descriptions can now describe registers for PowerPC.
5394 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
5395 registers on PowerPC targets.
5397 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
5398 targets even when the libthread_db library is not available.
5400 * The GDB remote stub, gdbserver, now supports the new file transfer
5401 commands (remote put, remote get, and remote delete).
5403 * The GDB remote stub, gdbserver, now supports run and attach in
5404 extended-remote mode.
5406 * hppa*64*-*-hpux11* target broken
5407 The debugger is unable to start a program and fails with the following
5408 error: "Error trying to get information about dynamic linker".
5409 The gdb-6.7 release is also affected.
5411 * GDB now supports the --enable-targets= configure option to allow
5412 building a single GDB executable that supports multiple remote
5413 target architectures.
5415 * GDB now supports debugging C and C++ programs which use the
5416 Decimal Floating Point extension. In addition, the PowerPC target
5417 now has a set of pseudo-registers to inspect decimal float values
5418 stored in two consecutive float registers.
5420 * The -break-insert MI command can optionally create pending
5423 * Improved support for debugging Ada
5424 Many improvements to the Ada language support have been made. These
5426 - Better support for Ada2005 interface types
5427 - Improved handling of arrays and slices in general
5428 - Better support for Taft-amendment types
5429 - The '{type} ADDRESS' expression is now allowed on the left hand-side
5431 - Improved command completion in Ada
5434 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
5439 set print frame-arguments (all|scalars|none)
5440 show print frame-arguments
5441 The value of this variable can be changed to control which argument
5442 values should be printed by the debugger when displaying a frame.
5447 Transfer files to and from a remote target, and delete remote files.
5454 Transfer files to and from a remote target, and delete remote files.
5456 * New remote packets
5463 Open, close, read, write, and delete files on the remote system.
5466 Attach to an existing process on the remote system, in extended-remote
5470 Run a new process on the remote system, in extended-remote mode.
5472 *** Changes in GDB 6.7
5474 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
5475 bfd, libiberty and opcodes, as revealed by static analysis donated by
5476 Coverity, Inc. (http://scan.coverity.com).
5478 * When looking up multiply-defined global symbols, GDB will now prefer the
5479 symbol definition in the current shared library if it was built using the
5480 -Bsymbolic linker option.
5482 * When the Text User Interface (TUI) is not configured, GDB will now
5483 recognize the -tui command-line option and print a message that the TUI
5486 * The GDB remote stub, gdbserver, now has lower overhead for high
5487 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
5489 * GDB for MIPS targets now autodetects whether a remote target provides
5490 32-bit or 64-bit register values.
5492 * Support for C++ member pointers has been improved.
5494 * GDB now understands XML target descriptions, which specify the
5495 target's overall architecture. GDB can read a description from
5496 a local file or over the remote serial protocol.
5498 * Vectors of single-byte data use a new integer type which is not
5499 automatically displayed as character or string data.
5501 * The /s format now works with the print command. It displays
5502 arrays of single-byte integers and pointers to single-byte integers
5505 * Target descriptions can now describe target-specific registers,
5506 for architectures which have implemented the support (currently
5507 only ARM, M68K, and MIPS).
5509 * GDB and the GDB remote stub, gdbserver, now support the XScale
5512 * The GDB remote stub, gdbserver, has been updated to support
5513 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
5514 has been rewritten to use the standard GDB remote protocol.
5516 * GDB can now step into C++ functions which are called through thunks.
5518 * GDB for the Cell/B.E. SPU now supports overlay debugging.
5520 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
5521 layout. It also supports a TextSeg= and DataSeg= response when only
5522 segment base addresses (rather than offsets) are available.
5524 * The /i format now outputs any trailing branch delay slot instructions
5525 immediately following the last instruction within the count specified.
5527 * The GDB remote protocol "T" stop reply packet now supports a
5528 "library" response. Combined with the new "qXfer:libraries:read"
5529 packet, this response allows GDB to debug shared libraries on targets
5530 where the operating system manages the list of loaded libraries (e.g.
5531 Windows and SymbianOS).
5533 * The GDB remote stub, gdbserver, now supports dynamic link libraries
5534 (DLLs) on Windows and Windows CE targets.
5536 * GDB now supports a faster verification that a .debug file matches its binary
5537 according to its build-id signature, if the signature is present.
5543 Enable or disable hardware flow control (RTS/CTS) on the serial port
5544 when debugging using remote targets.
5546 set mem inaccessible-by-default
5547 show mem inaccessible-by-default
5548 If the target supplies a memory map, for instance via the remote
5549 protocol's "qXfer:memory-map:read" packet, setting this variable
5550 prevents GDB from accessing memory outside the memory map. This
5551 is useful for targets with memory mapped registers or which react
5552 badly to accesses of unmapped address space.
5554 set breakpoint auto-hw
5555 show breakpoint auto-hw
5556 If the target supplies a memory map, for instance via the remote
5557 protocol's "qXfer:memory-map:read" packet, setting this variable
5558 lets GDB use hardware breakpoints automatically for memory regions
5559 where it can not use software breakpoints. This covers both the
5560 "break" command and internal breakpoints used for other commands
5561 including "next" and "finish".
5564 catch exception unhandled
5565 Stop the program execution when Ada exceptions are raised.
5568 Stop the program execution when an Ada assertion failed.
5572 Set an alternate system root for target files. This is a more
5573 general version of "set solib-absolute-prefix", which is now
5574 an alias to "set sysroot".
5577 Provide extended SPU facility status information. This set of
5578 commands is available only when debugging the Cell/B.E. SPU
5581 * New native configurations
5583 OpenBSD/sh sh*-*openbsd*
5586 unset tdesc filename
5588 Use the specified local file as an XML target description, and do
5589 not query the target for its built-in description.
5593 OpenBSD/sh sh*-*-openbsd*
5594 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
5595 Toshiba Media Processor mep-elf
5597 * New remote packets
5600 Ignore the specified signals; pass them directly to the debugged program
5601 without stopping other threads or reporting them to GDB.
5603 qXfer:features:read:
5604 Read an XML target description from the target, which describes its
5609 Read or write contents of an spufs file on the target system. These
5610 packets are available only on the Cell/B.E. SPU architecture.
5612 qXfer:libraries:read:
5613 Report the loaded shared libraries. Combined with new "T" packet
5614 response, this packet allows GDB to debug shared libraries on
5615 targets where the operating system manages the list of loaded
5616 libraries (e.g. Windows and SymbianOS).
5620 Support for these obsolete configurations has been removed.
5628 i[34567]86-*-lynxos*
5629 i[34567]86-*-netware*
5630 i[34567]86-*-sco3.2v5*
5631 i[34567]86-*-sco3.2v4*
5633 i[34567]86-*-sysv4.2*
5636 i[34567]86-*-unixware2*
5637 i[34567]86-*-unixware*
5646 * Other removed features
5653 Various m68k-only ROM monitors.
5660 Various Renesas ROM monitors and debugging interfaces for SH and
5665 Support for a Macraigor serial interface to on-chip debugging.
5666 GDB does not directly support the newer parallel or USB
5671 A debug information format. The predecessor to DWARF 2 and
5672 DWARF 3, which are still supported.
5674 Support for the HP aCC compiler on HP-UX/PA-RISC
5676 SOM-encapsulated symbolic debugging information, automatic
5677 invocation of pxdb, and the aCC custom C++ ABI. This does not
5678 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
5679 with aCC can still be debugged on an assembly level.
5681 MIPS ".pdr" sections
5683 A MIPS-specific format used to describe stack frame layout
5684 in debugging information.
5688 GDB could work with an older version of Guile to debug
5689 the interpreter and Scheme programs running in it.
5691 set mips stack-arg-size
5692 set mips saved-gpreg-size
5694 Use "set mips abi" to control parameter passing for MIPS.
5696 *** Changes in GDB 6.6
5701 Cell Broadband Engine SPU spu-elf
5703 * GDB can now be configured as a cross-debugger targeting native Windows
5704 (mingw32) or Cygwin. It can communicate with a remote debugging stub
5705 running on a Windows system over TCP/IP to debug Windows programs.
5707 * The GDB remote stub, gdbserver, has been updated to support Windows and
5708 Cygwin debugging. Both single-threaded and multi-threaded programs are
5711 * The "set trust-readonly-sections" command works again. This command was
5712 broken in GDB 6.3, 6.4, and 6.5.
5714 * The "load" command now supports writing to flash memory, if the remote
5715 stub provides the required support.
5717 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
5718 longer requires symbolic debug information (e.g. DWARF-2).
5723 unset substitute-path
5724 show substitute-path
5725 Manage a list of substitution rules that GDB uses to rewrite the name
5726 of the directories where the sources are located. This can be useful
5727 for instance when the sources were moved to a different location
5728 between compilation and debugging.
5732 Print each CLI command as it is executed. Each command is prefixed with
5733 a number of `+' symbols representing the nesting depth.
5734 The source command now has a `-v' option to enable the same feature.
5738 The ARM Demon monitor support (RDP protocol, "target rdp").
5740 Kernel Object Display, an embedded debugging feature which only worked with
5741 an obsolete version of Cisco IOS.
5743 The 'set download-write-size' and 'show download-write-size' commands.
5745 * New remote packets
5748 Tell a stub about GDB client features, and request remote target features.
5749 The first feature implemented is PacketSize, which allows the target to
5750 specify the size of packets it can handle - to minimize the number of
5751 packets required and improve performance when connected to a remote
5755 Fetch an OS auxilliary vector from the remote stub. This packet is a
5756 more efficient replacement for qPart:auxv:read.
5758 qXfer:memory-map:read:
5759 Fetch a memory map from the remote stub, including information about
5760 RAM, ROM, and flash memory devices.
5765 Erase and program a flash memory device.
5767 * Removed remote packets
5770 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
5771 used it, and only gdbserver implemented it.
5773 *** Changes in GDB 6.5
5777 Renesas M32C/M16C m32c-elf
5779 Morpho Technologies ms1 ms1-elf
5783 init-if-undefined Initialize a convenience variable, but
5784 only if it doesn't already have a value.
5786 The following commands are presently only implemented for native GNU/Linux:
5788 checkpoint Save a snapshot of the program state.
5790 restart <n> Return the program state to a
5791 previously saved state.
5793 info checkpoints List currently saved checkpoints.
5795 delete-checkpoint <n> Delete a previously saved checkpoint.
5797 set|show detach-on-fork Tell gdb whether to detach from a newly
5798 forked process, or to keep debugging it.
5800 info forks List forks of the user program that
5801 are available to be debugged.
5803 fork <n> Switch to debugging one of several
5804 forks of the user program that are
5805 available to be debugged.
5807 delete-fork <n> Delete a fork from the list of forks
5808 that are available to be debugged (and
5809 kill the forked process).
5811 detach-fork <n> Delete a fork from the list of forks
5812 that are available to be debugged (and
5813 allow the process to continue).
5817 Morpho Technologies ms2 ms1-elf
5819 * Improved Windows host support
5821 GDB now builds as a cross debugger hosted on i686-mingw32, including
5822 native console support, and remote communications using either
5823 network sockets or serial ports.
5825 * Improved Modula-2 language support
5827 GDB can now print most types in the Modula-2 syntax. This includes:
5828 basic types, set types, record types, enumerated types, range types,
5829 pointer types and ARRAY types. Procedure var parameters are correctly
5830 printed and hexadecimal addresses and character constants are also
5831 written in the Modula-2 syntax. Best results can be obtained by using
5832 GNU Modula-2 together with the -gdwarf-2 command line option.
5836 The ARM rdi-share module.
5838 The Netware NLM debug server.
5840 *** Changes in GDB 6.4
5842 * New native configurations
5844 OpenBSD/arm arm*-*-openbsd*
5845 OpenBSD/mips64 mips64-*-openbsd*
5849 Morpho Technologies ms1 ms1-elf
5851 * New command line options
5853 --batch-silent As for --batch, but totally silent.
5854 --return-child-result The debugger will exist with the same value
5855 the child (debugged) program exited with.
5856 --eval-command COMMAND, -ex COMMAND
5857 Execute a single GDB CLI command. This may be
5858 specified multiple times and in conjunction
5859 with the --command (-x) option.
5861 * Deprecated commands removed
5863 The following commands, that were deprecated in 2000, have been
5867 set|show arm disassembly-flavor set|show arm disassembler
5868 othernames set arm disassembler
5869 set|show remotedebug set|show debug remote
5870 set|show archdebug set|show debug arch
5871 set|show eventdebug set|show debug event
5874 * New BSD user-level threads support
5876 It is now possible to debug programs using the user-level threads
5877 library on OpenBSD and FreeBSD. Currently supported (target)
5880 FreeBSD/amd64 x86_64-*-freebsd*
5881 FreeBSD/i386 i386-*-freebsd*
5882 OpenBSD/i386 i386-*-openbsd*
5884 Note that the new kernel threads libraries introduced in FreeBSD 5.x
5885 are not yet supported.
5887 * New support for Matsushita MN10300 w/sim added
5888 (Work in progress). mn10300-elf.
5890 * REMOVED configurations and files
5892 VxWorks and the XDR protocol *-*-vxworks
5893 Motorola MCORE mcore-*-*
5894 National Semiconductor NS32000 ns32k-*-*
5896 * New "set print array-indexes" command
5898 After turning this setting "on", GDB prints the index of each element
5899 when displaying arrays. The default is "off" to preserve the previous
5902 * VAX floating point support
5904 GDB now supports the not-quite-ieee VAX F and D floating point formats.
5906 * User-defined command support
5908 In addition to using $arg0..$arg9 for argument passing, it is now possible
5909 to use $argc to determine now many arguments have been passed. See the
5910 section on user-defined commands in the user manual for more information.
5912 *** Changes in GDB 6.3:
5914 * New command line option
5916 GDB now accepts -l followed by a number to set the timeout for remote
5919 * GDB works with GCC -feliminate-dwarf2-dups
5921 GDB now supports a more compact representation of DWARF-2 debug
5922 information using DW_FORM_ref_addr references. These are produced
5923 by GCC with the option -feliminate-dwarf2-dups and also by some
5924 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
5925 to use -feliminate-dwarf2-dups.
5927 * Internationalization
5929 When supported by the host system, GDB will be built with
5930 internationalization (libintl). The task of marking up the sources is
5931 continued, we're looking forward to our first translation.
5935 Initial support for debugging programs compiled with the GNAT
5936 implementation of the Ada programming language has been integrated
5937 into GDB. In this release, support is limited to expression evaluation.
5939 * New native configurations
5941 GNU/Linux/m32r m32r-*-linux-gnu
5945 GDB's remote protocol now includes support for the 'p' packet. This
5946 packet is used to fetch individual registers from a remote inferior.
5948 * END-OF-LIFE registers[] compatibility module
5950 GDB's internal register infrastructure has been completely rewritten.
5951 The new infrastructure making possible the implementation of key new
5952 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
5955 GDB 6.3 will be the last release to include the registers[]
5956 compatibility module that allowed out-of-date configurations to
5957 continue to work. This change directly impacts the following
5967 powerpc bdm protocol
5969 Unless there is activity to revive these configurations, they will be
5970 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
5972 * OBSOLETE configurations and files
5974 Configurations that have been declared obsolete in this release have
5975 been commented out. Unless there is activity to revive these
5976 configurations, the next release of GDB will have their sources
5977 permanently REMOVED.
5986 *** Changes in GDB 6.2.1:
5988 * MIPS `break main; run' gave an heuristic-fence-post warning
5990 When attempting to run even a simple program, a warning about
5991 heuristic-fence-post being hit would be reported. This problem has
5994 * MIPS IRIX 'long double' crashed GDB
5996 When examining a long double variable, GDB would get a segmentation
5997 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
5998 IRIX long double values).
6002 A bug in the VAX stack code was causing problems with the "next"
6003 command. This problem has been fixed.
6005 *** Changes in GDB 6.2:
6007 * Fix for ``many threads''
6009 On GNU/Linux systems that use the NPTL threads library, a program
6010 rapidly creating and deleting threads would confuse GDB leading to the
6013 ptrace: No such process.
6014 thread_db_get_info: cannot get thread info: generic error
6016 This problem has been fixed.
6018 * "-async" and "-noasync" options removed.
6020 Support for the broken "-noasync" option has been removed (it caused
6023 * New ``start'' command.
6025 This command runs the program until the beginning of the main procedure.
6027 * New BSD Kernel Data Access Library (libkvm) interface
6029 Using ``target kvm'' it is now possible to debug kernel core dumps and
6030 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
6031 platforms. Currently supported (native-only) configurations are:
6033 FreeBSD/amd64 x86_64-*-freebsd*
6034 FreeBSD/i386 i?86-*-freebsd*
6035 NetBSD/i386 i?86-*-netbsd*
6036 NetBSD/m68k m68*-*-netbsd*
6037 NetBSD/sparc sparc-*-netbsd*
6038 OpenBSD/amd64 x86_64-*-openbsd*
6039 OpenBSD/i386 i?86-*-openbsd*
6040 OpenBSD/m68k m68*-openbsd*
6041 OpenBSD/sparc sparc-*-openbsd*
6043 * Signal trampoline code overhauled
6045 Many generic problems with GDB's signal handling code have been fixed.
6046 These include: backtraces through non-contiguous stacks; recognition
6047 of sa_sigaction signal trampolines; backtrace from a NULL pointer
6048 call; backtrace through a signal trampoline; step into and out of
6049 signal handlers; and single-stepping in the signal trampoline.
6051 Please note that kernel bugs are a limiting factor here. These
6052 features have been shown to work on an s390 GNU/Linux system that
6053 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
6055 * Cygwin support for DWARF 2 added.
6057 * New native configurations
6059 GNU/Linux/hppa hppa*-*-linux*
6060 OpenBSD/hppa hppa*-*-openbsd*
6061 OpenBSD/m68k m68*-*-openbsd*
6062 OpenBSD/m88k m88*-*-openbsd*
6063 OpenBSD/powerpc powerpc-*-openbsd*
6064 NetBSD/vax vax-*-netbsd*
6065 OpenBSD/vax vax-*-openbsd*
6067 * END-OF-LIFE frame compatibility module
6069 GDB's internal frame infrastructure has been completely rewritten.
6070 The new infrastructure making it possible to support key new features
6071 including DWARF 2 Call Frame Information. To aid in the task of
6072 migrating old configurations to this new infrastructure, a
6073 compatibility module, that allowed old configurations to continue to
6074 work, was also included.
6076 GDB 6.2 will be the last release to include this frame compatibility
6077 module. This change directly impacts the following configurations:
6087 Unless there is activity to revive these configurations, they will be
6088 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
6090 * REMOVED configurations and files
6092 Sun 3, running SunOS 3 m68*-*-sunos3*
6093 Sun 3, running SunOS 4 m68*-*-sunos4*
6094 Sun 2, running SunOS 3 m68000-*-sunos3*
6095 Sun 2, running SunOS 4 m68000-*-sunos4*
6096 Motorola 680x0 running LynxOS m68*-*-lynxos*
6097 AT&T 3b1/Unix pc m68*-att-*
6098 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
6099 decstation mips-dec-* mips-little-*
6100 riscos mips-*-riscos* mips-*-sysv*
6101 sonymips mips-sony-*
6102 sysv mips*-*-sysv4* (IRIX 5/6 not included)
6104 *** Changes in GDB 6.1.1:
6106 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
6108 The TUI (Text-mode User Interface) is now built as part of a default
6109 GDB configuration. It is enabled by either selecting the TUI with the
6110 command line option "-i=tui" or by running the separate "gdbtui"
6111 program. For more information on the TUI, see the manual "Debugging
6114 * Pending breakpoint support (also included in GDB 6.1)
6116 Support has been added to allow you to specify breakpoints in shared
6117 libraries that have not yet been loaded. If a breakpoint location
6118 cannot be found, and the "breakpoint pending" option is set to auto,
6119 GDB queries you if you wish to make the breakpoint pending on a future
6120 shared-library load. If and when GDB resolves the breakpoint symbol,
6121 the pending breakpoint is removed as one or more regular breakpoints
6124 Pending breakpoints are very useful for GCJ Java debugging.
6126 * Fixed ISO-C build problems
6128 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
6129 non ISO-C code that stopped them being built using a more strict ISO-C
6130 compiler (e.g., IBM's C compiler).
6132 * Fixed build problem on IRIX 5
6134 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
6135 wasn't able to compile compile on an IRIX 5 system.
6137 * Added execute permission to gdb/gdbserver/configure
6139 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
6140 permission. This bug would cause configure to fail on a number of
6141 systems (Solaris, IRIX). Ref: server/519.
6143 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
6145 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
6146 has been updated to use constant array sizes.
6148 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
6150 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
6151 its generated DWARF Call Frame Info. This encoding was causing GDB to
6152 panic, that panic has been fixed. Ref: gdb/1628.
6154 * Fixed a problem when examining parameters in shared library code.
6156 When examining parameters in optimized shared library code generated
6157 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
6158 not available''. GDB now correctly displays the variable's value.
6160 *** Changes in GDB 6.1:
6162 * Removed --with-mmalloc
6164 Support for the mmalloc memory manager has been removed, as it
6165 conflicted with the internal gdb byte cache.
6167 * Changes in AMD64 configurations
6169 The AMD64 target now includes the %cs and %ss registers. As a result
6170 the AMD64 remote protocol has changed; this affects the floating-point
6171 and SSE registers. If you rely on those registers for your debugging,
6172 you should upgrade gdbserver on the remote side.
6174 * Revised SPARC target
6176 The SPARC target has been completely revised, incorporating the
6177 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
6178 support for LynxOS and SunOS 4 has been dropped. Calling functions
6179 from within GDB on operating systems with a non-executable stack
6180 (Solaris, OpenBSD) now works.
6184 GDB has a new C++ demangler which does a better job on the mangled
6185 names generated by current versions of g++. It also runs faster, so
6186 with this and other changes gdb should now start faster on large C++
6189 * DWARF 2 Location Expressions
6191 GDB support for location expressions has been extended to support function
6192 arguments and frame bases. Older versions of GDB could crash when they
6195 * C++ nested types and namespaces
6197 GDB's support for nested types and namespaces in C++ has been
6198 improved, especially if you use the DWARF 2 debugging format. (This
6199 is the default for recent versions of GCC on most platforms.)
6200 Specifically, if you have a class "Inner" defined within a class or
6201 namespace "Outer", then GDB realizes that the class's name is
6202 "Outer::Inner", not simply "Inner". This should greatly reduce the
6203 frequency of complaints about not finding RTTI symbols. In addition,
6204 if you are stopped at inside of a function defined within a namespace,
6205 GDB modifies its name lookup accordingly.
6207 * New native configurations
6209 NetBSD/amd64 x86_64-*-netbsd*
6210 OpenBSD/amd64 x86_64-*-openbsd*
6211 OpenBSD/alpha alpha*-*-openbsd*
6212 OpenBSD/sparc sparc-*-openbsd*
6213 OpenBSD/sparc64 sparc64-*-openbsd*
6215 * New debugging protocols
6217 M32R with SDI protocol m32r-*-elf*
6219 * "set prompt-escape-char" command deleted.
6221 The command "set prompt-escape-char" has been deleted. This command,
6222 and its very obscure effect on GDB's prompt, was never documented,
6223 tested, nor mentioned in the NEWS file.
6225 * OBSOLETE configurations and files
6227 Configurations that have been declared obsolete in this release have
6228 been commented out. Unless there is activity to revive these
6229 configurations, the next release of GDB will have their sources
6230 permanently REMOVED.
6232 Sun 3, running SunOS 3 m68*-*-sunos3*
6233 Sun 3, running SunOS 4 m68*-*-sunos4*
6234 Sun 2, running SunOS 3 m68000-*-sunos3*
6235 Sun 2, running SunOS 4 m68000-*-sunos4*
6236 Motorola 680x0 running LynxOS m68*-*-lynxos*
6237 AT&T 3b1/Unix pc m68*-att-*
6238 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
6239 decstation mips-dec-* mips-little-*
6240 riscos mips-*-riscos* mips-*-sysv*
6241 sonymips mips-sony-*
6242 sysv mips*-*-sysv4* (IRIX 5/6 not included)
6244 * REMOVED configurations and files
6246 SGI Irix-4.x mips-sgi-irix4 or iris4
6247 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6248 Z8000 simulator z8k-zilog-none or z8ksim
6249 Matsushita MN10200 w/simulator mn10200-*-*
6250 H8/500 simulator h8500-hitachi-hms or h8500hms
6251 HP/PA running BSD hppa*-*-bsd*
6252 HP/PA running OSF/1 hppa*-*-osf*
6253 HP/PA Pro target hppa*-*-pro*
6254 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
6255 386BSD i[3456]86-*-bsd*
6256 Sequent family i[3456]86-sequent-sysv4*
6257 i[3456]86-sequent-sysv*
6258 i[3456]86-sequent-bsd*
6259 SPARC running LynxOS sparc-*-lynxos*
6260 SPARC running SunOS 4 sparc-*-sunos4*
6261 Tsqware Sparclet sparclet-*-*
6262 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6264 *** Changes in GDB 6.0:
6268 Support for debugging the Objective-C programming language has been
6269 integrated into GDB.
6271 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
6273 DWARF 2's Call Frame Information makes available compiler generated
6274 information that more exactly describes the program's run-time stack.
6275 By using this information, GDB is able to provide more robust stack
6278 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
6279 have been updated to use a new backtrace mechanism which includes
6280 DWARF 2 CFI support.
6284 GDB's remote protocol has been extended to include support for hosted
6285 file I/O (where the remote target uses GDB's file system). See GDB's
6286 remote protocol documentation for details.
6288 * All targets using the new architecture framework.
6290 All of GDB's targets have been updated to use the new internal
6291 architecture framework. The way is now open for future GDB releases
6292 to include cross-architecture native debugging support (i386 on amd64,
6295 * GNU/Linux's Thread Local Storage (TLS)
6297 GDB now includes support for for the GNU/Linux implementation of
6298 per-thread variables.
6300 * GNU/Linux's Native POSIX Thread Library (NPTL)
6302 GDB's thread code has been updated to work with either the new
6303 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
6305 * Separate debug info.
6307 GDB, in conjunction with BINUTILS, now supports a mechanism for
6308 automatically loading debug information from a separate file. Instead
6309 of shipping full debug and non-debug versions of system libraries,
6310 system integrators can now instead ship just the stripped libraries
6311 and optional debug files.
6313 * DWARF 2 Location Expressions
6315 DWARF 2 Location Expressions allow the compiler to more completely
6316 describe the location of variables (even in optimized code) to the
6319 GDB now includes preliminary support for location expressions (support
6320 for DW_OP_piece is still missing).
6324 A number of long standing bugs that caused GDB to die while starting a
6325 Java application have been fixed. GDB's Java support is now
6326 considered "useable".
6328 * GNU/Linux support for fork, vfork, and exec.
6330 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
6331 commands are now implemented for GNU/Linux. They require a 2.5.x or later
6334 * GDB supports logging output to a file
6336 There are two new commands, "set logging" and "show logging", which can be
6337 used to capture GDB's output to a file.
6339 * The meaning of "detach" has changed for gdbserver
6341 The "detach" command will now resume the application, as documented. To
6342 disconnect from gdbserver and leave it stopped, use the new "disconnect"
6345 * d10v, m68hc11 `regs' command deprecated
6347 The `info registers' command has been updated so that it displays the
6348 registers using a format identical to the old `regs' command.
6352 A new command, "maint set profile on/off", has been added. This command can
6353 be used to enable or disable profiling while running GDB, to profile a
6354 session or a set of commands. In addition there is a new configure switch,
6355 "--enable-profiling", which will cause GDB to be compiled with profiling
6356 data, for more informative profiling results.
6358 * Default MI syntax changed to "mi2".
6360 The default MI (machine interface) syntax, enabled by the command line
6361 option "-i=mi", has been changed to "mi2". The previous MI syntax,
6362 "mi1", can be enabled by specifying the option "-i=mi1".
6364 Support for the original "mi0" syntax (included in GDB 5.0) has been
6367 Fix for gdb/192: removed extraneous space when displaying frame level.
6368 Fix for gdb/672: update changelist is now output in mi list format.
6369 Fix for gdb/702: a -var-assign that updates the value now shows up
6370 in a subsequent -var-update.
6372 * New native configurations.
6374 FreeBSD/amd64 x86_64-*-freebsd*
6376 * Multi-arched targets.
6378 HP/PA HPUX11 hppa*-*-hpux*
6379 Renesas M32R/D w/simulator m32r-*-elf*
6381 * OBSOLETE configurations and files
6383 Configurations that have been declared obsolete in this release have
6384 been commented out. Unless there is activity to revive these
6385 configurations, the next release of GDB will have their sources
6386 permanently REMOVED.
6388 Z8000 simulator z8k-zilog-none or z8ksim
6389 Matsushita MN10200 w/simulator mn10200-*-*
6390 H8/500 simulator h8500-hitachi-hms or h8500hms
6391 HP/PA running BSD hppa*-*-bsd*
6392 HP/PA running OSF/1 hppa*-*-osf*
6393 HP/PA Pro target hppa*-*-pro*
6394 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
6395 Sequent family i[3456]86-sequent-sysv4*
6396 i[3456]86-sequent-sysv*
6397 i[3456]86-sequent-bsd*
6398 Tsqware Sparclet sparclet-*-*
6399 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6401 * REMOVED configurations and files
6404 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6405 IBM AIX PS/2 i[3456]86-*-aix
6406 i386 running Mach 3.0 i[3456]86-*-mach3*
6407 i386 running Mach i[3456]86-*-mach*
6408 i386 running OSF/1 i[3456]86-*osf1mk*
6409 HP/Apollo 68k Family m68*-apollo*-sysv*,
6411 m68*-hp-bsd*, m68*-hp-hpux*
6412 Argonaut Risc Chip (ARC) arc-*-*
6413 Mitsubishi D30V d30v-*-*
6414 Fujitsu FR30 fr30-*-elf*
6415 OS/9000 i[34]86-*-os9k
6416 I960 with MON960 i960-*-coff
6418 * MIPS $fp behavior changed
6420 The convenience variable $fp, for the MIPS, now consistently returns
6421 the address of the current frame's base. Previously, depending on the
6422 context, $fp could refer to either $sp or the current frame's base
6423 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
6424 The GNU Source-Level Debugger''.
6426 *** Changes in GDB 5.3:
6428 * GNU/Linux shared library multi-threaded performance improved.
6430 When debugging a multi-threaded application on GNU/Linux, GDB now uses
6431 `/proc', in preference to `ptrace' for memory reads. This may result
6432 in an improvement in the start-up time of multi-threaded, shared
6433 library applications when run under GDB. One GDB user writes: ``loads
6434 shared libs like mad''.
6436 * ``gdbserver'' now supports multi-threaded applications on some targets
6438 Support for debugging multi-threaded applications which use
6439 the GNU/Linux LinuxThreads package has been added for
6440 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
6441 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
6443 * GDB now supports C/C++ preprocessor macros.
6445 GDB now expands preprocessor macro invocations in C/C++ expressions,
6446 and provides various commands for showing macro definitions and how
6449 The new command `macro expand EXPRESSION' expands any macro
6450 invocations in expression, and shows the result.
6452 The new command `show macro MACRO-NAME' shows the definition of the
6453 macro named MACRO-NAME, and where it was defined.
6455 Most compilers don't include information about macros in the debugging
6456 information by default. In GCC 3.1, for example, you need to compile
6457 your program with the options `-gdwarf-2 -g3'. If the macro
6458 information is present in the executable, GDB will read it.
6460 * Multi-arched targets.
6462 DEC Alpha (partial) alpha*-*-*
6463 DEC VAX (partial) vax-*-*
6465 National Semiconductor NS32000 (partial) ns32k-*-*
6466 Motorola 68000 (partial) m68k-*-*
6467 Motorola MCORE mcore-*-*
6471 Fujitsu FRV architecture added by Red Hat frv*-*-*
6474 * New native configurations
6476 Alpha NetBSD alpha*-*-netbsd*
6477 SH NetBSD sh*-*-netbsdelf*
6478 MIPS NetBSD mips*-*-netbsd*
6479 UltraSPARC NetBSD sparc64-*-netbsd*
6481 * OBSOLETE configurations and files
6483 Configurations that have been declared obsolete in this release have
6484 been commented out. Unless there is activity to revive these
6485 configurations, the next release of GDB will have their sources
6486 permanently REMOVED.
6488 Mitsubishi D30V d30v-*-*
6489 OS/9000 i[34]86-*-os9k
6490 IBM AIX PS/2 i[3456]86-*-aix
6491 Fujitsu FR30 fr30-*-elf*
6492 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6493 Argonaut Risc Chip (ARC) arc-*-*
6494 i386 running Mach 3.0 i[3456]86-*-mach3*
6495 i386 running Mach i[3456]86-*-mach*
6496 i386 running OSF/1 i[3456]86-*osf1mk*
6497 HP/Apollo 68k Family m68*-apollo*-sysv*,
6499 m68*-hp-bsd*, m68*-hp-hpux*
6500 I960 with MON960 i960-*-coff
6502 * OBSOLETE languages
6504 CHILL, a Pascal like language used by telecommunications companies.
6506 * REMOVED configurations and files
6508 AMD 29k family via UDI a29k-amd-udi, udi29k
6509 A29K VxWorks a29k-*-vxworks
6510 AMD 29000 embedded, using EBMON a29k-none-none
6511 AMD 29000 embedded with COFF a29k-none-coff
6512 AMD 29000 embedded with a.out a29k-none-aout
6514 testsuite/gdb.hp/gdb.threads-hp/ directory
6516 * New command "set max-user-call-depth <nnn>"
6518 This command allows the user to limit the call depth of user-defined
6519 commands. The default is 1024.
6521 * Changes in FreeBSD/i386 native debugging.
6523 Support for the "generate-core-file" has been added.
6525 * New commands "dump", "append", and "restore".
6527 These commands allow data to be copied from target memory
6528 to a bfd-format or binary file (dump and append), and back
6529 from a file into memory (restore).
6531 * Improved "next/step" support on multi-processor Alpha Tru64.
6533 The previous single-step mechanism could cause unpredictable problems,
6534 including the random appearance of SIGSEGV or SIGTRAP signals. The use
6535 of a software single-step mechanism prevents this.
6537 *** Changes in GDB 5.2.1:
6545 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
6546 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
6547 Fix, by Joel Brobecker imported from mainline.
6549 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
6550 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
6551 Fix, by Fred Fish, imported from mainline.
6553 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
6554 Surprisingly enough, it works now.
6555 By Michal Ludvig, imported from mainline.
6557 i386 hardware watchpoint support:
6558 avoid misses on second run for some targets.
6559 By Pierre Muller, imported from mainline.
6561 *** Changes in GDB 5.2:
6563 * New command "set trust-readonly-sections on[off]".
6565 This command is a hint that tells gdb that read-only sections
6566 really are read-only (ie. that their contents will not change).
6567 In this mode, gdb will go to the object file rather than the
6568 target to read memory from read-only sections (such as ".text").
6569 This can be a significant performance improvement on some
6570 (notably embedded) targets.
6572 * New command "generate-core-file" (or "gcore").
6574 This new gdb command allows the user to drop a core file of the child
6575 process state at any time. So far it's been implemented only for
6576 GNU/Linux and Solaris, but should be relatively easily ported to other
6577 hosts. Argument is core file name (defaults to core.<pid>).
6579 * New command line option
6581 GDB now accepts --pid or -p followed by a process id.
6583 * Change in command line behavior -- corefiles vs. process ids.
6585 There is a subtle behavior in the way in which GDB handles
6586 command line arguments. The first non-flag argument is always
6587 a program to debug, but the second non-flag argument may either
6588 be a corefile or a process id. Previously, GDB would attempt to
6589 open the second argument as a corefile, and if that failed, would
6590 issue a superfluous error message and then attempt to attach it as
6591 a process. Now, if the second argument begins with a non-digit,
6592 it will be treated as a corefile. If it begins with a digit,
6593 GDB will attempt to attach it as a process, and if no such process
6594 is found, will then attempt to open it as a corefile.
6596 * Changes in ARM configurations.
6598 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
6599 configuration is fully multi-arch.
6601 * New native configurations
6603 ARM NetBSD arm*-*-netbsd*
6604 x86 OpenBSD i[3456]86-*-openbsd*
6605 AMD x86-64 running GNU/Linux x86_64-*-linux-*
6606 Sparc64 running FreeBSD sparc64-*-freebsd*
6610 Sanyo XStormy16 xstormy16-elf
6612 * OBSOLETE configurations and files
6614 Configurations that have been declared obsolete in this release have
6615 been commented out. Unless there is activity to revive these
6616 configurations, the next release of GDB will have their sources
6617 permanently REMOVED.
6619 AMD 29k family via UDI a29k-amd-udi, udi29k
6620 A29K VxWorks a29k-*-vxworks
6621 AMD 29000 embedded, using EBMON a29k-none-none
6622 AMD 29000 embedded with COFF a29k-none-coff
6623 AMD 29000 embedded with a.out a29k-none-aout
6625 testsuite/gdb.hp/gdb.threads-hp/ directory
6627 * REMOVED configurations and files
6629 TI TMS320C80 tic80-*-*
6631 PowerPC Solaris powerpcle-*-solaris*
6632 PowerPC Windows NT powerpcle-*-cygwin32
6633 PowerPC Netware powerpc-*-netware*
6634 Harris/CXUX m88k m88*-harris-cxux*
6635 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
6636 ns32k-utek-sysv* ns32k-utek-*
6637 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
6638 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
6639 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
6640 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
6641 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
6643 * Changes to command line processing
6645 The new `--args' feature can be used to specify command-line arguments
6646 for the inferior from gdb's command line.
6648 * Changes to key bindings
6650 There is a new `operate-and-get-next' function bound to `C-o'.
6652 *** Changes in GDB 5.1.1
6654 Fix compile problem on DJGPP.
6656 Fix a problem with floating-point registers on the i386 being
6659 Fix to stop GDB crashing on .debug_str debug info.
6661 Numerous documentation fixes.
6663 Numerous testsuite fixes.
6665 *** Changes in GDB 5.1:
6667 * New native configurations
6669 Alpha FreeBSD alpha*-*-freebsd*
6670 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
6671 MIPS GNU/Linux mips*-*-linux*
6672 MIPS SGI Irix 6.x mips*-sgi-irix6*
6673 ia64 AIX ia64-*-aix*
6674 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
6678 Motorola 68HC11 and 68HC12 m68hc11-elf
6680 UltraSparc running GNU/Linux sparc64-*-linux*
6682 * OBSOLETE configurations and files
6684 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
6685 Harris/CXUX m88k m88*-harris-cxux*
6686 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
6687 ns32k-utek-sysv* ns32k-utek-*
6688 TI TMS320C80 tic80-*-*
6690 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
6691 PowerPC Solaris powerpcle-*-solaris*
6692 PowerPC Windows NT powerpcle-*-cygwin32
6693 PowerPC Netware powerpc-*-netware*
6694 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
6695 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
6696 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
6697 Apple Macintosh (MPW) host N/A
6699 stuff.c (Program to stuff files into a specially prepared space in kdb)
6700 kdb-start.c (Main loop for the standalone kernel debugger)
6702 Configurations that have been declared obsolete in this release have
6703 been commented out. Unless there is activity to revive these
6704 configurations, the next release of GDB will have their sources
6705 permanently REMOVED.
6707 * REMOVED configurations and files
6709 Altos 3068 m68*-altos-*
6710 Convex c1-*-*, c2-*-*
6712 ARM RISCix arm-*-* (as host)
6716 * GDB has been converted to ISO C.
6718 GDB's source code has been converted to ISO C. In particular, the
6719 sources are fully protoized, and rely on standard headers being
6724 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
6726 * The MI enabled by default.
6728 The new machine oriented interface (MI) introduced in GDB 5.0 has been
6729 revised and enabled by default. Packages which use GDB as a debugging
6730 engine behind a UI or another front end are encouraged to switch to
6731 using the GDB/MI interface, instead of the old annotations interface
6732 which is now deprecated.
6734 * Support for debugging Pascal programs.
6736 GDB now includes support for debugging Pascal programs. The following
6737 main features are supported:
6739 - Pascal-specific data types such as sets;
6741 - automatic recognition of Pascal sources based on file-name
6744 - Pascal-style display of data types, variables, and functions;
6746 - a Pascal expression parser.
6748 However, some important features are not yet supported.
6750 - Pascal string operations are not supported at all;
6752 - there are some problems with boolean types;
6754 - Pascal type hexadecimal constants are not supported
6755 because they conflict with the internal variables format;
6757 - support for Pascal objects and classes is not full yet;
6759 - unlike Pascal, GDB is case-sensitive for symbol names.
6761 * Changes in completion.
6763 Commands such as `shell', `run' and `set args', which pass arguments
6764 to inferior programs, now complete on file names, similar to what
6765 users expect at the shell prompt.
6767 Commands which accept locations, such as `disassemble', `print',
6768 `breakpoint', `until', etc. now complete on filenames as well as
6769 program symbols. Thus, if you type "break foob TAB", and the source
6770 files linked into the programs include `foobar.c', that file name will
6771 be one of the candidates for completion. However, file names are not
6772 considered for completion after you typed a colon that delimits a file
6773 name from a name of a function in that file, as in "break foo.c:bar".
6775 `set demangle-style' completes on available demangling styles.
6777 * New platform-independent commands:
6779 It is now possible to define a post-hook for a command as well as a
6780 hook that runs before the command. For more details, see the
6781 documentation of `hookpost' in the GDB manual.
6783 * Changes in GNU/Linux native debugging.
6785 Support for debugging multi-threaded programs has been completely
6786 revised for all platforms except m68k and sparc. You can now debug as
6787 many threads as your system allows you to have.
6789 Attach/detach is supported for multi-threaded programs.
6791 Support for SSE registers was added for x86. This doesn't work for
6792 multi-threaded programs though.
6794 * Changes in MIPS configurations.
6796 Multi-arch support is enabled for all MIPS configurations.
6798 GDB can now be built as native debugger on SGI Irix 6.x systems for
6799 debugging n32 executables. (Debugging 64-bit executables is not yet
6802 * Unified support for hardware watchpoints in all x86 configurations.
6804 Most (if not all) native x86 configurations support hardware-assisted
6805 breakpoints and watchpoints in a unified manner. This support
6806 implements debug register sharing between watchpoints, which allows to
6807 put a virtually infinite number of watchpoints on the same address,
6808 and also supports watching regions up to 16 bytes with several debug
6811 The new maintenance command `maintenance show-debug-regs' toggles
6812 debugging print-outs in functions that insert, remove, and test
6813 watchpoints and hardware breakpoints.
6815 * Changes in the DJGPP native configuration.
6817 New command ``info dos sysinfo'' displays assorted information about
6818 the CPU, OS, memory, and DPMI server.
6820 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
6821 display information about segment descriptors stored in GDT, LDT, and
6824 New commands ``info dos pde'' and ``info dos pte'' display entries
6825 from Page Directory and Page Tables (for now works with CWSDPMI only).
6826 New command ``info dos address-pte'' displays the Page Table entry for
6827 a given linear address.
6829 GDB can now pass command lines longer than 126 characters to the
6830 program being debugged (requires an update to the libdbg.a library
6831 which is part of the DJGPP development kit).
6833 DWARF2 debug info is now supported.
6835 It is now possible to `step' and `next' through calls to `longjmp'.
6837 * Changes in documentation.
6839 All GDB documentation was converted to GFDL, the GNU Free
6840 Documentation License.
6842 Tracepoints-related commands are now fully documented in the GDB
6845 TUI, the Text-mode User Interface, is now documented in the manual.
6847 Tracepoints-related commands are now fully documented in the GDB
6850 The "GDB Internals" manual now has an index. It also includes
6851 documentation of `ui_out' functions, GDB coding standards, x86
6852 hardware watchpoints, and memory region attributes.
6854 * GDB's version number moved to ``version.in''
6856 The Makefile variable VERSION has been replaced by the file
6857 ``version.in''. People creating GDB distributions should update the
6858 contents of this file.
6862 GUD support is now a standard part of the EMACS distribution.
6864 *** Changes in GDB 5.0:
6866 * Improved support for debugging FP programs on x86 targets
6868 Unified and much-improved support for debugging floating-point
6869 programs on all x86 targets. In particular, ``info float'' now
6870 displays the FP registers in the same format on all x86 targets, with
6871 greater level of detail.
6873 * Improvements and bugfixes in hardware-assisted watchpoints
6875 It is now possible to watch array elements, struct members, and
6876 bitfields with hardware-assisted watchpoints. Data-read watchpoints
6877 on x86 targets no longer erroneously trigger when the address is
6880 * Improvements in the native DJGPP version of GDB
6882 The distribution now includes all the scripts and auxiliary files
6883 necessary to build the native DJGPP version on MS-DOS/MS-Windows
6884 machines ``out of the box''.
6886 The DJGPP version can now debug programs that use signals. It is
6887 possible to catch signals that happened in the debuggee, deliver
6888 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
6889 would kill the program being debugged.) Programs that hook hardware
6890 interrupts (keyboard, timer, etc.) can also be debugged.
6892 It is now possible to debug DJGPP programs that redirect their
6893 standard handles or switch them to raw (as opposed to cooked) mode, or
6894 even close them. The command ``run < foo > bar'' works as expected,
6895 and ``info terminal'' reports useful information about the debuggee's
6896 terminal, including raw/cooked mode, redirection, etc.
6898 The DJGPP version now uses termios functions for console I/O, which
6899 enables debugging graphics programs. Interrupting GDB with Ctrl-C
6902 DOS-style file names with drive letters are now fully supported by
6905 It is now possible to debug DJGPP programs that switch their working
6906 directory. It is also possible to rerun the debuggee any number of
6907 times without restarting GDB; thus, you can use the same setup,
6908 breakpoints, etc. for many debugging sessions.
6910 * New native configurations
6912 ARM GNU/Linux arm*-*-linux*
6913 PowerPC GNU/Linux powerpc-*-linux*
6917 Motorola MCore mcore-*-*
6918 x86 VxWorks i[3456]86-*-vxworks*
6919 PowerPC VxWorks powerpc-*-vxworks*
6920 TI TMS320C80 tic80-*-*
6922 * OBSOLETE configurations
6924 Altos 3068 m68*-altos-*
6925 Convex c1-*-*, c2-*-*
6927 ARM RISCix arm-*-* (as host)
6930 Configurations that have been declared obsolete will be commented out,
6931 but the code will be left in place. If there is no activity to revive
6932 these configurations before the next release of GDB, the sources will
6933 be permanently REMOVED.
6935 * Gould support removed
6937 Support for the Gould PowerNode and NP1 has been removed.
6939 * New features for SVR4
6941 On SVR4 native platforms (such as Solaris), if you attach to a process
6942 without first loading a symbol file, GDB will now attempt to locate and
6943 load symbols from the running process's executable file.
6945 * Many C++ enhancements
6947 C++ support has been greatly improved. Overload resolution now works properly
6948 in almost all cases. RTTI support is on the way.
6950 * Remote targets can connect to a sub-program
6952 A popen(3) style serial-device has been added. This device starts a
6953 sub-process (such as a stand-alone simulator) and then communicates
6954 with that. The sub-program to run is specified using the syntax
6955 ``|<program> <args>'' vis:
6957 (gdb) set remotedebug 1
6958 (gdb) target extended-remote |mn10300-elf-sim program-args
6960 * MIPS 64 remote protocol
6962 A long standing bug in the mips64 remote protocol where by GDB
6963 expected certain 32 bit registers (ex SR) to be transfered as 32
6964 instead of 64 bits has been fixed.
6966 The command ``set remote-mips64-transfers-32bit-regs on'' has been
6967 added to provide backward compatibility with older versions of GDB.
6969 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
6971 The command ``set remotebinarydownload'' command has been replaced by
6972 ``set remote X-packet''. Other commands in ``set remote'' family
6973 include ``set remote P-packet''.
6975 * Breakpoint commands accept ranges.
6977 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
6978 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
6979 ``tracepoint passcount'' also accepts a range of tracepoints.
6981 * ``apropos'' command added.
6983 The ``apropos'' command searches through command names and
6984 documentation strings, printing out matches, making it much easier to
6985 try to find a command that does what you are looking for.
6989 A new machine oriented interface (MI) has been added to GDB. This
6990 interface is designed for debug environments running GDB as a separate
6991 process. This is part of the long term libGDB project. See the
6992 "GDB/MI" chapter of the GDB manual for further information. It can be
6993 enabled by configuring with:
6995 .../configure --enable-gdbmi
6997 *** Changes in GDB-4.18:
6999 * New native configurations
7001 HP-UX 10.20 hppa*-*-hpux10.20
7002 HP-UX 11.x hppa*-*-hpux11.0*
7003 M68K GNU/Linux m68*-*-linux*
7007 Fujitsu FR30 fr30-*-elf*
7008 Intel StrongARM strongarm-*-*
7009 Mitsubishi D30V d30v-*-*
7011 * OBSOLETE configurations
7013 Gould PowerNode, NP1 np1-*-*, pn-*-*
7015 Configurations that have been declared obsolete will be commented out,
7016 but the code will be left in place. If there is no activity to revive
7017 these configurations before the next release of GDB, the sources will
7018 be permanently REMOVED.
7022 As a compatibility experiment, GDB's source files buildsym.h and
7023 buildsym.c have been converted to pure standard C, no longer
7024 containing any K&R compatibility code. We believe that all systems in
7025 use today either come with a standard C compiler, or have a GCC port
7026 available. If this is not true, please report the affected
7027 configuration to bug-gdb@gnu.org immediately. See the README file for
7028 information about getting a standard C compiler if you don't have one
7033 GDB now uses readline 2.2.
7035 * set extension-language
7037 You can now control the mapping between filename extensions and source
7038 languages by using the `set extension-language' command. For instance,
7039 you can ask GDB to treat .c files as C++ by saying
7040 set extension-language .c c++
7041 The command `info extensions' lists all of the recognized extensions
7042 and their associated languages.
7044 * Setting processor type for PowerPC and RS/6000
7046 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
7047 you can use the `set processor' command to specify what variant of the
7048 PowerPC family you are debugging. The command
7052 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
7053 following PowerPC and RS6000 variants:
7055 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
7056 rs6000 IBM RS6000 ("POWER") architecture, user-level view
7058 403GC IBM PowerPC 403GC
7059 505 Motorola PowerPC 505
7060 860 Motorola PowerPC 860 or 850
7061 601 Motorola PowerPC 601
7062 602 Motorola PowerPC 602
7063 603 Motorola/IBM PowerPC 603 or 603e
7064 604 Motorola PowerPC 604 or 604e
7065 750 Motorola/IBM PowerPC 750 or 750
7067 At the moment, this command just tells GDB what to name the
7068 special-purpose processor registers. Since almost all the affected
7069 registers are inaccessible to user-level programs, this command is
7070 only useful for remote debugging in its present form.
7074 Thanks to a major code donation from Hewlett-Packard, GDB now has much
7075 more extensive support for HP-UX. Added features include shared
7076 library support, kernel threads and hardware watchpoints for 11.00,
7077 support for HP's ANSI C and C++ compilers, and a compatibility mode
7078 for xdb and dbx commands.
7082 HP's donation includes the new concept of catchpoints, which is a
7083 generalization of the old catch command. On HP-UX, it is now possible
7084 to catch exec, fork, and vfork, as well as library loading.
7086 This means that the existing catch command has changed; its first
7087 argument now specifies the type of catch to be set up. See the
7088 output of "help catch" for a list of catchpoint types.
7090 * Debugging across forks
7092 On HP-UX, you can choose which process to debug when a fork() happens
7097 HP has donated a curses-based terminal user interface (TUI). To get
7098 it, build with --enable-tui. Although this can be enabled for any
7099 configuration, at present it only works for native HP debugging.
7101 * GDB remote protocol additions
7103 A new protocol packet 'X' that writes binary data is now available.
7104 Default behavior is to try 'X', then drop back to 'M' if the stub
7105 fails to respond. The settable variable `remotebinarydownload'
7106 allows explicit control over the use of 'X'.
7108 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
7109 full 64-bit address. The command
7111 set remoteaddresssize 32
7113 can be used to revert to the old behaviour. For existing remote stubs
7114 the change should not be noticed, as the additional address information
7117 In order to assist in debugging stubs, you may use the maintenance
7118 command `packet' to send any text string to the stub. For instance,
7120 maint packet heythere
7122 sends the packet "$heythere#<checksum>". Note that it is very easy to
7123 disrupt a debugging session by sending the wrong packet at the wrong
7126 The compare-sections command allows you to compare section data on the
7127 target to what is in the executable file without uploading or
7128 downloading, by comparing CRC checksums.
7130 * Tracing can collect general expressions
7132 You may now collect general expressions at tracepoints. This requires
7133 further additions to the target-side stub; see tracepoint.c and
7134 doc/agentexpr.texi for further details.
7136 * mask-address variable for Mips
7138 For Mips targets, you may control the zeroing of the upper 32 bits of
7139 a 64-bit address by entering `set mask-address on'. This is mainly
7140 of interest to users of embedded R4xxx and R5xxx processors.
7142 * Higher serial baud rates
7144 GDB's serial code now allows you to specify baud rates 57600, 115200,
7145 230400, and 460800 baud. (Note that your host system may not be able
7146 to achieve all of these rates.)
7150 The i960 configuration now includes an initial implementation of a
7151 builtin simulator, contributed by Jim Wilson.
7154 *** Changes in GDB-4.17:
7156 * New native configurations
7158 Alpha GNU/Linux alpha*-*-linux*
7159 Unixware 2.x i[3456]86-unixware2*
7160 Irix 6.x mips*-sgi-irix6*
7161 PowerPC GNU/Linux powerpc-*-linux*
7162 PowerPC Solaris powerpcle-*-solaris*
7163 Sparc GNU/Linux sparc-*-linux*
7164 Motorola sysV68 R3V7.1 m68k-motorola-sysv
7168 Argonaut Risc Chip (ARC) arc-*-*
7169 Hitachi H8/300S h8300*-*-*
7170 Matsushita MN10200 w/simulator mn10200-*-*
7171 Matsushita MN10300 w/simulator mn10300-*-*
7172 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
7173 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
7174 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
7175 Mitsubishi D10V w/simulator d10v-*-*
7176 Mitsubishi M32R/D w/simulator m32r-*-elf*
7177 Tsqware Sparclet sparclet-*-*
7178 NEC V850 w/simulator v850-*-*
7180 * New debugging protocols
7182 ARM with RDI protocol arm*-*-*
7183 M68K with dBUG monitor m68*-*-{aout,coff,elf}
7184 DDB and LSI variants of PMON protocol mips*-*-*
7185 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
7186 PowerPC with SDS protocol powerpc{,le}-*-eabi
7187 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
7191 All configurations can now understand and use the DWARF 2 debugging
7192 format. The choice is automatic, if the symbol file contains DWARF 2
7197 GDB now includes basic Java language support. This support is
7198 only useful with Java compilers that produce native machine code.
7200 * solib-absolute-prefix and solib-search-path
7202 For SunOS and SVR4 shared libraries, you may now set the prefix for
7203 loading absolute shared library symbol files, and the search path for
7204 locating non-absolute shared library symbol files.
7206 * Live range splitting
7208 GDB can now effectively debug code for which GCC has performed live
7209 range splitting as part of its optimization. See gdb/doc/LRS for
7210 more details on the expected format of the stabs information.
7214 GDB's support for the GNU Hurd, including thread debugging, has been
7215 updated to work with current versions of the Hurd.
7219 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
7220 instruction set. ARM GDB automatically detects when Thumb
7221 instructions are in use, and adjusts disassembly and backtracing
7226 GDB's MIPS target configurations now handle the MIP16 16-bit
7231 GDB now includes support for overlays; if an executable has been
7232 linked such that multiple sections are based at the same address, GDB
7233 will decide which section to use for symbolic info. You can choose to
7234 control the decision manually, using overlay commands, or implement
7235 additional target-side support and use "overlay load-target" to bring
7236 in the overlay mapping. Do "help overlay" for more detail.
7240 The command "info symbol <address>" displays information about
7241 the symbol at the specified address.
7245 The standard remote protocol now includes an extension that allows
7246 asynchronous collection and display of trace data. This requires
7247 extensive support in the target-side debugging stub. Tracing mode
7248 includes a new interaction mode in GDB and new commands: see the
7249 file tracepoint.c for more details.
7253 Configurations for embedded MIPS now include a simulator contributed
7254 by Cygnus Solutions. The simulator supports the instruction sets
7255 of most MIPS variants.
7259 Sparc configurations may now include the ERC32 simulator contributed
7260 by the European Space Agency. The simulator is not built into
7261 Sparc targets by default; configure with --enable-sim to include it.
7265 For target configurations that may include multiple variants of a
7266 basic architecture (such as MIPS and SH), you may now set the
7267 architecture explicitly. "set arch" sets, "info arch" lists
7268 the possible architectures.
7270 *** Changes in GDB-4.16:
7272 * New native configurations
7274 Windows 95, x86 Windows NT i[345]86-*-cygwin32
7275 M68K NetBSD m68k-*-netbsd*
7276 PowerPC AIX 4.x powerpc-*-aix*
7277 PowerPC MacOS powerpc-*-macos*
7278 PowerPC Windows NT powerpcle-*-cygwin32
7279 RS/6000 AIX 4.x rs6000-*-aix4*
7283 ARM with RDP protocol arm-*-*
7284 I960 with MON960 i960-*-coff
7285 MIPS VxWorks mips*-*-vxworks*
7286 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
7287 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
7289 Matra Sparclet sparclet-*-*
7293 The powerpc-eabi configuration now includes the PSIM simulator,
7294 contributed by Andrew Cagney, with assistance from Mike Meissner.
7295 PSIM is a very elaborate model of the PowerPC, including not only
7296 basic instruction set execution, but also details of execution unit
7297 performance and I/O hardware. See sim/ppc/README for more details.
7301 GDB now works with Solaris 2.5.
7303 * Windows 95/NT native
7305 GDB will now work as a native debugger on Windows 95 and Windows NT.
7306 To build it from source, you must use the "gnu-win32" environment,
7307 which uses a DLL to emulate enough of Unix to run the GNU tools.
7308 Further information, binaries, and sources are available at
7309 ftp.cygnus.com, under pub/gnu-win32.
7311 * dont-repeat command
7313 If a user-defined command includes the command `dont-repeat', then the
7314 command will not be repeated if the user just types return. This is
7315 useful if the command is time-consuming to run, so that accidental
7316 extra keystrokes don't run the same command many times.
7318 * Send break instead of ^C
7320 The standard remote protocol now includes an option to send a break
7321 rather than a ^C to the target in order to interrupt it. By default,
7322 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
7324 * Remote protocol timeout
7326 The standard remote protocol includes a new variable `remotetimeout'
7327 that allows you to set the number of seconds before GDB gives up trying
7328 to read from the target. The default value is 2.
7330 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
7332 By default GDB will automatically keep track of objects as they are
7333 loaded and unloaded by the dynamic linker. By using the command `set
7334 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
7335 when shared library events occur, thus allowing you to set breakpoints
7336 in shared libraries which are explicitly loaded by the inferior.
7338 Note this feature does not work on hpux8. On hpux9 you must link
7339 /usr/lib/end.o into your program. This feature should work
7340 automatically on hpux10.
7342 * Irix 5.x hardware watchpoint support
7344 Irix 5 configurations now support the use of hardware watchpoints.
7346 * Mips protocol "SYN garbage limit"
7348 When debugging a Mips target using the `target mips' protocol, you
7349 may set the number of characters that GDB will ignore by setting
7350 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
7351 every character. The default value is 1050.
7353 * Recording and replaying remote debug sessions
7355 If you set `remotelogfile' to the name of a file, gdb will write to it
7356 a recording of a remote debug session. This recording may then be
7357 replayed back to gdb using "gdbreplay". See gdbserver/README for
7358 details. This is useful when you have a problem with GDB while doing
7359 remote debugging; you can make a recording of the session and send it
7360 to someone else, who can then recreate the problem.
7362 * Speedups for remote debugging
7364 GDB includes speedups for downloading and stepping MIPS systems using
7365 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
7366 and more efficient S-record downloading.
7368 * Memory use reductions and statistics collection
7370 GDB now uses less memory and reports statistics about memory usage.
7371 Try the `maint print statistics' command, for example.
7373 *** Changes in GDB-4.15:
7375 * Psymtabs for XCOFF
7377 The symbol reader for AIX GDB now uses partial symbol tables. This
7378 can greatly improve startup time, especially for large executables.
7380 * Remote targets use caching
7382 Remote targets now use a data cache to speed up communication with the
7383 remote side. The data cache could lead to incorrect results because
7384 it doesn't know about volatile variables, thus making it impossible to
7385 debug targets which use memory mapped I/O devices. `set remotecache
7386 off' turns the data cache off.
7388 * Remote targets may have threads
7390 The standard remote protocol now includes support for multiple threads
7391 in the target system, using new protocol commands 'H' and 'T'. See
7392 gdb/remote.c for details.
7396 If GDB is configured with `--enable-netrom', then it will include
7397 support for the NetROM ROM emulator from XLNT Designs. The NetROM
7398 acts as though it is a bank of ROM on the target board, but you can
7399 write into it over the network. GDB's support consists only of
7400 support for fast loading into the emulated ROM; to debug, you must use
7401 another protocol, such as standard remote protocol. The usual
7402 sequence is something like
7404 target nrom <netrom-hostname>
7406 target remote <netrom-hostname>:1235
7410 GDB now includes support for the Apple Macintosh, as a host only. It
7411 may be run as either an MPW tool or as a standalone application, and
7412 it can debug through the serial port. All the usual GDB commands are
7413 available, but to the target command, you must supply "serial" as the
7414 device type instead of "/dev/ttyXX". See mpw-README in the main
7415 directory for more information on how to build. The MPW configuration
7416 scripts */mpw-config.in support only a few targets, and only the
7417 mips-idt-ecoff target has been tested.
7421 GDB configuration now uses autoconf. This is not user-visible,
7422 but does simplify configuration and building.
7426 GDB now supports hpux10.
7428 *** Changes in GDB-4.14:
7430 * New native configurations
7432 x86 FreeBSD i[345]86-*-freebsd
7433 x86 NetBSD i[345]86-*-netbsd
7434 NS32k NetBSD ns32k-*-netbsd
7435 Sparc NetBSD sparc-*-netbsd
7439 A29K VxWorks a29k-*-vxworks
7440 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
7441 CPU32 EST-300 emulator m68*-*-est*
7442 PowerPC ELF powerpc-*-elf
7445 * Alpha OSF/1 support for procfs
7447 GDB now supports procfs under OSF/1-2.x and higher, which makes it
7448 possible to attach to running processes. As the mounting of the /proc
7449 filesystem is optional on the Alpha, GDB automatically determines
7450 the availability of /proc during startup. This can lead to problems
7451 if /proc is unmounted after GDB has been started.
7453 * Arguments to user-defined commands
7455 User commands may accept up to 10 arguments separated by whitespace.
7456 Arguments are accessed within the user command via $arg0..$arg9. A
7459 print $arg0 + $arg1 + $arg2
7461 To execute the command use:
7464 Defines the command "adder" which prints the sum of its three arguments.
7465 Note the arguments are text substitutions, so they may reference variables,
7466 use complex expressions, or even perform inferior function calls.
7468 * New `if' and `while' commands
7470 This makes it possible to write more sophisticated user-defined
7471 commands. Both commands take a single argument, which is the
7472 expression to evaluate, and must be followed by the commands to
7473 execute, one per line, if the expression is nonzero, the list being
7474 terminated by the word `end'. The `if' command list may include an
7475 `else' word, which causes the following commands to be executed only
7476 if the expression is zero.
7478 * Fortran source language mode
7480 GDB now includes partial support for Fortran 77. It will recognize
7481 Fortran programs and can evaluate a subset of Fortran expressions, but
7482 variables and functions may not be handled correctly. GDB will work
7483 with G77, but does not yet know much about symbols emitted by other
7486 * Better HPUX support
7488 Most debugging facilities now work on dynamic executables for HPPAs
7489 running hpux9 or later. You can attach to running dynamically linked
7490 processes, but by default the dynamic libraries will be read-only, so
7491 for instance you won't be able to put breakpoints in them. To change
7492 that behavior do the following before running the program:
7498 This will cause the libraries to be mapped private and read-write.
7499 To revert to the normal behavior, do this:
7505 You cannot set breakpoints or examine data in the library until after
7506 the library is loaded if the function/data symbols do not have
7509 GDB can now also read debug symbols produced by the HP C compiler on
7510 HPPAs (sorry, no C++, Fortran or 68k support).
7512 * Target byte order now dynamically selectable
7514 You can choose which byte order to use with a target system, via the
7515 commands "set endian big" and "set endian little", and you can see the
7516 current setting by using "show endian". You can also give the command
7517 "set endian auto", in which case GDB will use the byte order
7518 associated with the executable. Currently, only embedded MIPS
7519 configurations support dynamic selection of target byte order.
7521 * New DOS host serial code
7523 This version uses DPMI interrupts to handle buffered I/O, so you
7524 no longer need to run asynctsr when debugging boards connected to
7527 *** Changes in GDB-4.13:
7529 * New "complete" command
7531 This lists all the possible completions for the rest of the line, if it
7532 were to be given as a command itself. This is intended for use by emacs.
7534 * Trailing space optional in prompt
7536 "set prompt" no longer adds a space for you after the prompt you set. This
7537 allows you to set a prompt which ends in a space or one that does not.
7539 * Breakpoint hit counts
7541 "info break" now displays a count of the number of times the breakpoint
7542 has been hit. This is especially useful in conjunction with "ignore"; you
7543 can ignore a large number of breakpoint hits, look at the breakpoint info
7544 to see how many times the breakpoint was hit, then run again, ignoring one
7545 less than that number, and this will get you quickly to the last hit of
7548 * Ability to stop printing at NULL character
7550 "set print null-stop" will cause GDB to stop printing the characters of
7551 an array when the first NULL is encountered. This is useful when large
7552 arrays actually contain only short strings.
7554 * Shared library breakpoints
7556 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
7557 breakpoints in shared libraries before the executable is run.
7559 * Hardware watchpoints
7561 There is a new hardware breakpoint for the watch command for sparclite
7562 targets. See gdb/sparclite/hw_breakpoint.note.
7564 Hardware watchpoints are also now supported under GNU/Linux.
7568 Annotations have been added. These are for use with graphical interfaces,
7569 and are still experimental. Currently only gdba.el uses these.
7571 * Improved Irix 5 support
7573 GDB now works properly with Irix 5.2.
7575 * Improved HPPA support
7577 GDB now works properly with the latest GCC and GAS.
7579 * New native configurations
7581 Sequent PTX4 i[34]86-sequent-ptx4
7582 HPPA running OSF/1 hppa*-*-osf*
7583 Atari TT running SVR4 m68*-*-sysv4*
7584 RS/6000 LynxOS rs6000-*-lynxos*
7588 OS/9000 i[34]86-*-os9k
7589 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
7592 * Hitachi SH7000 and E7000-PC ICE support
7594 There is now support for communicating with the Hitachi E7000-PC ICE.
7595 This is available automatically when GDB is configured for the SH.
7599 As usual, a variety of small fixes and improvements, both generic
7600 and configuration-specific. See the ChangeLog for more detail.
7602 *** Changes in GDB-4.12:
7604 * Irix 5 is now supported
7608 GDB-4.12 on the HPPA has a number of changes which make it unable
7609 to debug the output from the currently released versions of GCC and
7610 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
7611 of GCC and GAS, versions of these tools designed to work with GDB-4.12
7612 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
7615 *** Changes in GDB-4.11:
7617 * User visible changes:
7621 The "set remotedebug" option is now consistent between the mips remote
7622 target, remote targets using the gdb-specific protocol, UDI (AMD's
7623 debug protocol for the 29k) and the 88k bug monitor. It is now an
7624 integer specifying a debug level (normally 0 or 1, but 2 means more
7625 debugging info for the mips target).
7627 * DEC Alpha native support
7629 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
7630 debug info, but GDB works fairly well with the DEC compiler and should
7631 work with a future GCC release. See the README file for a few
7632 Alpha-specific notes.
7634 * Preliminary thread implementation
7636 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
7638 * LynxOS native and target support for 386
7640 This release has been hosted on LynxOS 2.2, and also can be configured
7641 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
7644 * Improvements in C++ mangling/demangling.
7646 This release has much better g++ debugging, specifically in name
7647 mangling/demangling, virtual function calls, print virtual table,
7648 call methods, ...etc.
7650 *** Changes in GDB-4.10:
7652 * User visible changes:
7654 Remote debugging using the GDB-specific (`target remote') protocol now
7655 supports the `load' command. This is only useful if you have some
7656 other way of getting the stub to the target system, and you can put it
7657 somewhere in memory where it won't get clobbered by the download.
7659 Filename completion now works.
7661 When run under emacs mode, the "info line" command now causes the
7662 arrow to point to the line specified. Also, "info line" prints
7663 addresses in symbolic form (as well as hex).
7665 All vxworks based targets now support a user settable option, called
7666 vxworks-timeout. This option represents the number of seconds gdb
7667 should wait for responses to rpc's. You might want to use this if
7668 your vxworks target is, perhaps, a slow software simulator or happens
7669 to be on the far side of a thin network line.
7673 This release contains support for using a DEC alpha as a GDB host for
7674 cross debugging. Native alpha debugging is not supported yet.
7677 *** Changes in GDB-4.9:
7681 This is the first GDB release which is accompanied by a matching testsuite.
7682 The testsuite requires installation of dejagnu, which should be available
7683 via ftp from most sites that carry GNU software.
7687 'Cfront' style demangling has had its name changed to 'ARM' style, to
7688 emphasize that it was written from the specifications in the C++ Annotated
7689 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
7690 disclaimers, it still generated too much confusion with users attempting to
7691 use gdb with AT&T cfront.
7695 GDB now uses a standard remote interface to a simulator library.
7696 So far, the library contains simulators for the Zilog Z8001/2, the
7697 Hitachi H8/300, H8/500 and Super-H.
7699 * New targets supported
7701 H8/300 simulator h8300-hitachi-hms or h8300hms
7702 H8/500 simulator h8500-hitachi-hms or h8500hms
7703 SH simulator sh-hitachi-hms or sh
7704 Z8000 simulator z8k-zilog-none or z8ksim
7705 IDT MIPS board over serial line mips-idt-ecoff
7707 Cross-debugging to GO32 targets is supported. It requires a custom
7708 version of the i386-stub.c module which is integrated with the
7709 GO32 memory extender.
7711 * New remote protocols
7713 MIPS remote debugging protocol.
7715 * New source languages supported
7717 This version includes preliminary support for Chill, a Pascal like language
7718 used by telecommunications companies. Chill support is also being integrated
7719 into the GNU compiler, but we don't know when it will be publically available.
7722 *** Changes in GDB-4.8:
7724 * HP Precision Architecture supported
7726 GDB now supports HP PA-RISC machines running HPUX. A preliminary
7727 version of this support was available as a set of patches from the
7728 University of Utah. GDB does not support debugging of programs
7729 compiled with the HP compiler, because HP will not document their file
7730 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
7731 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
7733 Many problems in the preliminary version have been fixed.
7735 * Faster and better demangling
7737 We have improved template demangling and fixed numerous bugs in the GNU style
7738 demangler. It can now handle type modifiers such as `static' or `const'. Wide
7739 character types (wchar_t) are now supported. Demangling of each symbol is now
7740 only done once, and is cached when the symbol table for a file is read in.
7741 This results in a small increase in memory usage for C programs, a moderate
7742 increase in memory usage for C++ programs, and a fantastic speedup in
7745 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
7746 from the specifications in the Annotated Reference Manual, which AT&T's
7747 compiler does not actually implement.
7749 * G++ multiple inheritance compiler problem
7751 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
7752 inheritance lattices was reworked to properly discover ambiguities. We
7753 recently found an example which causes this new algorithm to fail in a
7754 very subtle way, producing bad debug information for those classes.
7755 The file 'gcc.patch' (in this directory) can be applied to gcc to
7756 circumvent the problem. A future GCC release will contain a complete
7759 The previous G++ debug info problem (mentioned below for the gdb-4.7
7760 release) is fixed in gcc version 2.3.2.
7762 * Improved configure script
7764 The `configure' script will now attempt to guess your system type if
7765 you don't supply a host system type. The old scheme of supplying a
7766 host system triplet is preferable over using this. All the magic is
7767 done in the new `config.guess' script. Examine it for details.
7769 We have also brought our configure script much more in line with the FSF's
7770 version. It now supports the --with-xxx options. In particular,
7771 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
7772 The resulting GDB will not be able to read arbitrary object file formats --
7773 only the format ``expected'' to be used on the configured target system.
7774 We hope to make this the default in a future release.
7776 * Documentation improvements
7778 There's new internal documentation on how to modify GDB, and how to
7779 produce clean changes to the code. We implore people to read it
7780 before submitting changes.
7782 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
7783 M4 macros. The new texinfo.tex is provided in this release. Pre-built
7784 `info' files are also provided. To build `info' files from scratch,
7785 you will need the latest `makeinfo' release, which will be available in
7786 a future texinfo-X.Y release.
7788 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
7789 We're not sure exactly which versions have this problem, but it has
7790 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
7791 or better. If that isn't possible, there is a patch in
7792 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
7793 around this problem.
7797 GDB now supports array constants that can be used in expressions typed in by
7798 the user. The syntax is `{element, element, ...}'. Ie: you can now type
7799 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
7802 The new directory `gdb/sparclite' contains a program that demonstrates
7803 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
7805 * New native hosts supported
7807 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
7808 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
7810 * New targets supported
7812 AMD 29k family via UDI a29k-amd-udi or udi29k
7814 * New file formats supported
7816 BFD now supports reading HP/PA-RISC executables (SOM file format?),
7817 HPUX core files, and SCO 3.2v2 core files.
7821 Attaching to processes now works again; thanks for the many bug reports.
7823 We have also stomped on a bunch of core dumps caused by
7824 printf_filtered("%s") problems.
7826 We eliminated a copyright problem on the rpc and ptrace header files
7827 for VxWorks, which was discovered at the last minute during the 4.7
7828 release. You should now be able to build a VxWorks GDB.
7830 You can now interrupt gdb while an attached process is running. This
7831 will cause the attached process to stop, and give control back to GDB.
7833 We fixed problems caused by using too many file descriptors
7834 for reading symbols from object files and libraries. This was
7835 especially a problem for programs that used many (~100) shared
7838 The `step' command now only enters a subroutine if there is line number
7839 information for the subroutine. Otherwise it acts like the `next'
7840 command. Previously, `step' would enter subroutines if there was
7841 any debugging information about the routine. This avoids problems
7842 when using `cc -g1' on MIPS machines.
7844 * Internal improvements
7846 GDB's internal interfaces have been improved to make it easier to support
7847 debugging of multiple languages in the future.
7849 GDB now uses a common structure for symbol information internally.
7850 Minimal symbols (derived from linkage symbols in object files), partial
7851 symbols (from a quick scan of debug information), and full symbols
7852 contain a common subset of information, making it easier to write
7853 shared code that handles any of them.
7855 * New command line options
7857 We now accept --silent as an alias for --quiet.
7861 The memory-mapped-malloc library is now licensed under the GNU Library
7862 General Public License.
7864 *** Changes in GDB-4.7:
7866 * Host/native/target split
7868 GDB has had some major internal surgery to untangle the support for
7869 hosts and remote targets. Now, when you configure GDB for a remote
7870 target, it will no longer load in all of the support for debugging
7871 local programs on the host. When fully completed and tested, this will
7872 ensure that arbitrary host/target combinations are possible.
7874 The primary conceptual shift is to separate the non-portable code in
7875 GDB into three categories. Host specific code is required any time GDB
7876 is compiled on that host, regardless of the target. Target specific
7877 code relates to the peculiarities of the target, but can be compiled on
7878 any host. Native specific code is everything else: it can only be
7879 built when the host and target are the same system. Child process
7880 handling and core file support are two common `native' examples.
7882 GDB's use of /proc for controlling Unix child processes is now cleaner.
7883 It has been split out into a single module under the `target_ops' vector,
7884 plus two native-dependent functions for each system that uses /proc.
7886 * New hosts supported
7888 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
7889 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7890 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
7892 * New targets supported
7894 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
7895 68030 and CPU32 m68030-*-*, m68332-*-*
7897 * New native hosts supported
7899 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7900 (386bsd is not well tested yet)
7901 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
7903 * New file formats supported
7905 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
7906 supports reading of `a.out.adobe' object files, which are an a.out
7907 format extended with minimal information about multiple sections.
7911 `show copying' is the same as the old `info copying'.
7912 `show warranty' is the same as `info warrantee'.
7913 These were renamed for consistency. The old commands continue to work.
7915 `info handle' is a new alias for `info signals'.
7917 You can now define pre-command hooks, which attach arbitrary command
7918 scripts to any command. The commands in the hook will be executed
7919 prior to the user's command. You can also create a hook which will be
7920 executed whenever the program stops. See gdb.texinfo.
7924 We now deal with Cfront style name mangling, and can even extract type
7925 info from mangled symbols. GDB can automatically figure out which
7926 symbol mangling style your C++ compiler uses.
7928 Calling of methods and virtual functions has been improved as well.
7932 The crash that occurred when debugging Sun Ansi-C compiled binaries is
7933 fixed. This was due to mishandling of the extra N_SO stabs output
7936 We also finally got Ultrix 4.2 running in house, and fixed core file
7937 support, with help from a dozen people on the net.
7939 John M. Farrell discovered that the reason that single-stepping was so
7940 slow on all of the Mips based platforms (primarily SGI and DEC) was
7941 that we were trying to demangle and lookup a symbol used for internal
7942 purposes on every instruction that was being stepped through. Changing
7943 the name of that symbol so that it couldn't be mistaken for a C++
7944 mangled symbol sped things up a great deal.
7946 Rich Pixley sped up symbol lookups in general by getting much smarter
7947 about when C++ symbol mangling is necessary. This should make symbol
7948 completion (TAB on the command line) much faster. It's not as fast as
7949 we'd like, but it's significantly faster than gdb-4.6.
7953 A new user controllable variable 'call_scratch_address' can
7954 specify the location of a scratch area to be used when GDB
7955 calls a function in the target. This is necessary because the
7956 usual method of putting the scratch area on the stack does not work
7957 in systems that have separate instruction and data spaces.
7959 We integrated changes to support the 29k UDI (Universal Debugger
7960 Interface), but discovered at the last minute that we didn't have all
7961 of the appropriate copyright paperwork. We are working with AMD to
7962 resolve this, and hope to have it available soon.
7966 We have sped up the remote serial line protocol, especially for targets
7967 with lots of registers. It now supports a new `expedited status' ('T')
7968 message which can be used in place of the existing 'S' status message.
7969 This allows the remote stub to send only the registers that GDB
7970 needs to make a quick decision about single-stepping or conditional
7971 breakpoints, eliminating the need to fetch the entire register set for
7972 each instruction being stepped through.
7974 The GDB remote serial protocol now implements a write-through cache for
7975 registers, only re-reading the registers if the target has run.
7977 There is also a new remote serial stub for SPARC processors. You can
7978 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
7979 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
7980 processor with a serial port.
7984 Configure.in files have become much easier to read and modify. A new
7985 `table driven' format makes it more obvious what configurations are
7986 supported, and what files each one uses.
7990 There is a new opcodes library which will eventually contain all of the
7991 disassembly routines and opcode tables. At present, it only contains
7992 Sparc and Z8000 routines. This will allow the assembler, debugger, and
7993 disassembler (binutils/objdump) to share these routines.
7995 The libiberty library is now copylefted under the GNU Library General
7996 Public License. This allows more liberal use, and was done so libg++
7997 can use it. This makes no difference to GDB, since the Library License
7998 grants all the rights from the General Public License.
8002 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
8003 reference to the stabs symbol info used by the debugger. It is (as far
8004 as we know) the only published document on this fascinating topic. We
8005 encourage you to read it, compare it to the stabs information on your
8006 system, and send improvements on the document in general (to
8007 bug-gdb@prep.ai.mit.edu).
8009 And, of course, many bugs have been fixed.
8012 *** Changes in GDB-4.6:
8014 * Better support for C++ function names
8016 GDB now accepts as input the "demangled form" of C++ overloaded function
8017 names and member function names, and can do command completion on such names
8018 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
8019 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
8020 Make use of command completion, it is your friend.
8022 GDB also now accepts a variety of C++ mangled symbol formats. They are
8023 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
8024 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
8025 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
8026 for the list of formats.
8028 * G++ symbol mangling problem
8030 Recent versions of gcc have a bug in how they emit debugging information for
8031 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
8032 directory) can be applied to gcc to fix the problem. Alternatively, if you
8033 can't fix gcc, you can #define GCC_MANGLE_BUG when compiling gdb/symtab.c. The
8034 usual symptom is difficulty with setting breakpoints on methods. GDB complains
8035 about the method being non-existent. (We believe that version 2.2.2 of GCC has
8038 * New 'maintenance' command
8040 All of the commands related to hacking GDB internals have been moved out of
8041 the main command set, and now live behind the 'maintenance' command. This
8042 can also be abbreviated as 'mt'. The following changes were made:
8044 dump-me -> maintenance dump-me
8045 info all-breakpoints -> maintenance info breakpoints
8046 printmsyms -> maintenance print msyms
8047 printobjfiles -> maintenance print objfiles
8048 printpsyms -> maintenance print psymbols
8049 printsyms -> maintenance print symbols
8051 The following commands are new:
8053 maintenance demangle Call internal GDB demangler routine to
8054 demangle a C++ link name and prints the result.
8055 maintenance print type Print a type chain for a given symbol
8057 * Change to .gdbinit file processing
8059 We now read the $HOME/.gdbinit file before processing the argv arguments
8060 (e.g. reading symbol files or core files). This allows global parameters to
8061 be set, which will apply during the symbol reading. The ./.gdbinit is still
8062 read after argv processing.
8064 * New hosts supported
8066 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
8068 GNU/Linux support i386-unknown-linux or linux
8070 We are also including code to support the HP/PA running BSD and HPUX. This
8071 is almost guaranteed not to work, as we didn't have time to test or build it
8072 for this release. We are including it so that the more adventurous (or
8073 masochistic) of you can play with it. We also had major problems with the
8074 fact that the compiler that we got from HP doesn't support the -g option.
8077 * New targets supported
8079 Hitachi H8/300 h8300-hitachi-hms or h8300hms
8081 * More smarts about finding #include files
8083 GDB now remembers the compilation directory for all include files, and for
8084 all files from which C is generated (like yacc and lex sources). This
8085 greatly improves GDB's ability to find yacc/lex sources, and include files,
8086 especially if you are debugging your program from a directory different from
8087 the one that contains your sources.
8089 We also fixed a bug which caused difficulty with listing and setting
8090 breakpoints in include files which contain C code. (In the past, you had to
8091 try twice in order to list an include file that you hadn't looked at before.)
8093 * Interesting infernals change
8095 GDB now deals with arbitrary numbers of sections, where the symbols for each
8096 section must be relocated relative to that section's landing place in the
8097 target's address space. This work was needed to support ELF with embedded
8098 stabs used by Solaris-2.0.
8100 * Bug fixes (of course!)
8102 There have been loads of fixes for the following things:
8103 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
8104 i960, stabs, DOS(GO32), procfs, etc...
8106 See the ChangeLog for details.
8108 *** Changes in GDB-4.5:
8110 * New machines supported (host and target)
8112 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
8114 SGI Irix-4.x mips-sgi-irix4 or iris4
8116 * New malloc package
8118 GDB now uses a new memory manager called mmalloc, based on gmalloc.
8119 Mmalloc is capable of handling multiple heaps of memory. It is also
8120 capable of saving a heap to a file, and then mapping it back in later.
8121 This can be used to greatly speedup the startup of GDB by using a
8122 pre-parsed symbol table which lives in a mmalloc managed heap. For
8123 more details, please read mmalloc/mmalloc.texi.
8127 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
8128 'help info proc' for details.
8130 * MIPS ecoff symbol table format
8132 The code that reads MIPS symbol table format is now supported on all hosts.
8133 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
8136 * File name changes for MS-DOS
8138 Many files in the config directories have been renamed to make it easier to
8139 support GDB on MS-DOSe systems (which have very restrictive file name
8140 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
8141 environment) is close to working but has some remaining problems. Note
8142 that debugging of DOS programs is not supported, due to limitations
8143 in the ``operating system'', but it can be used to host cross-debugging.
8145 * Cross byte order fixes
8147 Many fixes have been made to support cross debugging of Sparc and MIPS
8148 targets from hosts whose byte order differs.
8150 * New -mapped and -readnow options
8152 If memory-mapped files are available on your system through the 'mmap'
8153 system call, you can use the -mapped option on the `file' or
8154 `symbol-file' commands to cause GDB to write the symbols from your
8155 program into a reusable file. If the program you are debugging is
8156 called `/path/fred', the mapped symbol file will be `./fred.syms'.
8157 Future GDB debugging sessions will notice the presence of this file,
8158 and will quickly map in symbol information from it, rather than reading
8159 the symbol table from the executable program. Using the '-mapped'
8160 option in a GDB `file' or `symbol-file' command has the same effect as
8161 starting GDB with the '-mapped' command-line option.
8163 You can cause GDB to read the entire symbol table immediately by using
8164 the '-readnow' option with any of the commands that load symbol table
8165 information (or on the GDB command line). This makes the command
8166 slower, but makes future operations faster.
8168 The -mapped and -readnow options are typically combined in order to
8169 build a `fred.syms' file that contains complete symbol information.
8170 A simple GDB invocation to do nothing but build a `.syms' file for future
8173 gdb -batch -nx -mapped -readnow programname
8175 The `.syms' file is specific to the host machine on which GDB is run.
8176 It holds an exact image of GDB's internal symbol table. It cannot be
8177 shared across multiple host platforms.
8179 * longjmp() handling
8181 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
8182 siglongjmp() without losing control. This feature has not yet been ported to
8183 all systems. It currently works on many 386 platforms, all MIPS-based
8184 platforms (SGI, DECstation, etc), and Sun3/4.
8188 Preliminary work has been put in to support the new Solaris OS from Sun. At
8189 this time, it can control and debug processes, but it is not capable of
8194 As always, many many bug fixes. The major areas were with g++, and mipsread.
8195 People using the MIPS-based platforms should experience fewer mysterious
8196 crashes and trashed symbol tables.
8198 *** Changes in GDB-4.4:
8200 * New machines supported (host and target)
8202 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
8204 BSD Reno on Vax vax-dec-bsd
8205 Ultrix on Vax vax-dec-ultrix
8207 * New machines supported (target)
8209 AMD 29000 embedded, using EBMON a29k-none-none
8213 GDB continues to improve its handling of C++. `References' work better.
8214 The demangler has also been improved, and now deals with symbols mangled as
8215 per the Annotated C++ Reference Guide.
8217 GDB also now handles `stabs' symbol information embedded in MIPS
8218 `ecoff' symbol tables. Since the ecoff format was not easily
8219 extensible to handle new languages such as C++, this appeared to be a
8220 good way to put C++ debugging info into MIPS binaries. This option
8221 will be supported in the GNU C compiler, version 2, when it is
8224 * New features for SVR4
8226 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
8227 shared libraries. Debugging dynamically linked programs should present
8228 only minor differences from debugging statically linked programs.
8230 The `info proc' command will print out information about any process
8231 on an SVR4 system (including the one you are debugging). At the moment,
8232 it prints the address mappings of the process.
8234 If you bring up GDB on another SVR4 system, please send mail to
8235 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
8237 * Better dynamic linking support in SunOS
8239 Reading symbols from shared libraries which contain debugging symbols
8240 now works properly. However, there remain issues such as automatic
8241 skipping of `transfer vector' code during function calls, which
8242 make it harder to debug code in a shared library, than to debug the
8243 same code linked statically.
8247 GDB is now using the latest `getopt' routines from the FSF. This
8248 version accepts the -- prefix for options with long names. GDB will
8249 continue to accept the old forms (-option and +option) as well.
8250 Various single letter abbreviations for options have been explicity
8251 added to the option table so that they won't get overshadowed in the
8252 future by other options that begin with the same letter.
8256 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
8257 Many assorted bugs have been handled. Many more remain to be handled.
8258 See the various ChangeLog files (primarily in gdb and bfd) for details.
8261 *** Changes in GDB-4.3:
8263 * New machines supported (host and target)
8265 Amiga 3000 running Amix m68k-cbm-svr4 or amix
8266 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
8267 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
8269 * Almost SCO Unix support
8271 We had hoped to support:
8272 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
8273 (except for core file support), but we discovered very late in the release
8274 that it has problems with process groups that render gdb unusable. Sorry
8275 about that. I encourage people to fix it and post the fixes.
8277 * Preliminary ELF and DWARF support
8279 GDB can read ELF object files on System V Release 4, and can handle
8280 debugging records for C, in DWARF format, in ELF files. This support
8281 is preliminary. If you bring up GDB on another SVR4 system, please
8282 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
8287 GDB now uses the latest `readline' library. One user-visible change
8288 is that two tabs will list possible command completions, which previously
8289 required typing M-? (meta-question mark, or ESC ?).
8293 The `stepi' bug that many of you noticed has been squashed.
8294 Many bugs in C++ have been handled. Many more remain to be handled.
8295 See the various ChangeLog files (primarily in gdb and bfd) for details.
8297 * State of the MIPS world (in case you wondered):
8299 GDB can understand the symbol tables emitted by the compilers
8300 supplied by most vendors of MIPS-based machines, including DEC. These
8301 symbol tables are in a format that essentially nobody else uses.
8303 Some versions of gcc come with an assembler post-processor called
8304 mips-tfile. This program is required if you want to do source-level
8305 debugging of gcc-compiled programs. I believe FSF does not ship
8306 mips-tfile with gcc version 1, but it will eventually come with gcc
8309 Debugging of g++ output remains a problem. g++ version 1.xx does not
8310 really support it at all. (If you're lucky, you should be able to get
8311 line numbers and stack traces to work, but no parameters or local
8312 variables.) With some work it should be possible to improve the
8315 When gcc version 2 is released, you will have somewhat better luck.
8316 However, even then you will get confusing results for inheritance and
8319 We will eventually provide full debugging of g++ output on
8320 DECstations. This will probably involve some kind of stabs-in-ecoff
8321 encapulation, but the details have not been worked out yet.
8324 *** Changes in GDB-4.2:
8326 * Improved configuration
8328 Only one copy of `configure' exists now, and it is not self-modifying.
8329 Porting BFD is simpler.
8333 The `step' and `next' commands now only stop at the first instruction
8334 of a source line. This prevents the multiple stops that used to occur
8335 in switch statements, for-loops, etc. `Step' continues to stop if a
8336 function that has debugging information is called within the line.
8340 Lots of small bugs fixed. More remain.
8342 * New host supported (not target)
8344 Intel 386 PC clone running Mach i386-none-mach
8347 *** Changes in GDB-4.1:
8349 * Multiple source language support
8351 GDB now has internal scaffolding to handle several source languages.
8352 It determines the type of each source file from its filename extension,
8353 and will switch expression parsing and number formatting to match the
8354 language of the function in the currently selected stack frame.
8355 You can also specifically set the language to be used, with
8356 `set language c' or `set language modula-2'.
8360 GDB now has preliminary support for the GNU Modula-2 compiler,
8361 currently under development at the State University of New York at
8362 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
8363 continue through the fall of 1991 and into 1992.
8365 Other Modula-2 compilers are currently not supported, and attempting to
8366 debug programs compiled with them will likely result in an error as the
8367 symbol table is read. Feel free to work on it, though!
8369 There are hooks in GDB for strict type checking and range checking,
8370 in the `Modula-2 philosophy', but they do not currently work.
8374 GDB can now write to executable and core files (e.g. patch
8375 a variable's value). You must turn this switch on, specify
8376 the file ("exec foo" or "core foo"), *then* modify it, e.g.
8377 by assigning a new value to a variable. Modifications take
8380 * Automatic SunOS shared library reading
8382 When you run your program, GDB automatically determines where its
8383 shared libraries (if any) have been loaded, and reads their symbols.
8384 The `share' command is no longer needed. This also works when
8385 examining core files.
8389 You can specify the number of lines that the `list' command shows.
8392 * New machines supported (host and target)
8394 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
8395 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
8396 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
8398 * New hosts supported (not targets)
8400 IBM RT/PC: romp-ibm-aix or rtpc
8402 * New targets supported (not hosts)
8404 AMD 29000 embedded with COFF a29k-none-coff
8405 AMD 29000 embedded with a.out a29k-none-aout
8406 Ultracomputer remote kernel debug a29k-nyu-kern
8408 * New remote interfaces
8414 *** Changes in GDB-4.0:
8418 Wide output is wrapped at good places to make the output more readable.
8420 Gdb now supports cross-debugging from a host machine of one type to a
8421 target machine of another type. Communication with the target system
8422 is over serial lines. The ``target'' command handles connecting to the
8423 remote system; the ``load'' command will download a program into the
8424 remote system. Serial stubs for the m68k and i386 are provided. Gdb
8425 also supports debugging of realtime processes running under VxWorks,
8426 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
8427 stub on the target system.
8429 New CPUs supported include the AMD 29000 and Intel 960.
8431 GDB now reads object files and symbol tables via a ``binary file''
8432 library, which allows a single copy of GDB to debug programs of multiple
8433 object file types such as a.out and coff.
8435 There is now a GDB reference card in "doc/refcard.tex". (Make targets
8436 refcard.dvi and refcard.ps are available to format it).
8439 * Control-Variable user interface simplified
8441 All variables that control the operation of the debugger can be set
8442 by the ``set'' command, and displayed by the ``show'' command.
8444 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
8445 ``Show prompt'' produces the response:
8446 Gdb's prompt is new-gdb=>.
8448 What follows are the NEW set commands. The command ``help set'' will
8449 print a complete list of old and new set commands. ``help set FOO''
8450 will give a longer description of the variable FOO. ``show'' will show
8451 all of the variable descriptions and their current settings.
8453 confirm on/off: Enables warning questions for operations that are
8454 hard to recover from, e.g. rerunning the program while
8455 it is already running. Default is ON.
8457 editing on/off: Enables EMACS style command line editing
8458 of input. Previous lines can be recalled with
8459 control-P, the current line can be edited with control-B,
8460 you can search for commands with control-R, etc.
8463 history filename NAME: NAME is where the gdb command history
8464 will be stored. The default is .gdb_history,
8465 or the value of the environment variable
8468 history size N: The size, in commands, of the command history. The
8469 default is 256, or the value of the environment variable
8472 history save on/off: If this value is set to ON, the history file will
8473 be saved after exiting gdb. If set to OFF, the
8474 file will not be saved. The default is OFF.
8476 history expansion on/off: If this value is set to ON, then csh-like
8477 history expansion will be performed on
8478 command line input. The default is OFF.
8480 radix N: Sets the default radix for input and output. It can be set
8481 to 8, 10, or 16. Note that the argument to "radix" is interpreted
8482 in the current radix, so "set radix 10" is always a no-op.
8484 height N: This integer value is the number of lines on a page. Default
8485 is 24, the current `stty rows'' setting, or the ``li#''
8486 setting from the termcap entry matching the environment
8489 width N: This integer value is the number of characters on a line.
8490 Default is 80, the current `stty cols'' setting, or the ``co#''
8491 setting from the termcap entry matching the environment
8494 Note: ``set screensize'' is obsolete. Use ``set height'' and
8495 ``set width'' instead.
8497 print address on/off: Print memory addresses in various command displays,
8498 such as stack traces and structure values. Gdb looks
8499 more ``symbolic'' if you turn this off; it looks more
8500 ``machine level'' with it on. Default is ON.
8502 print array on/off: Prettyprint arrays. New convenient format! Default
8505 print demangle on/off: Print C++ symbols in "source" form if on,
8508 print asm-demangle on/off: Same, for assembler level printouts
8511 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
8514 * Support for Epoch Environment.
8516 The epoch environment is a version of Emacs v18 with windowing. One
8517 new command, ``inspect'', is identical to ``print'', except that if you
8518 are running in the epoch environment, the value is printed in its own
8522 * Support for Shared Libraries
8524 GDB can now debug programs and core files that use SunOS shared libraries.
8525 Symbols from a shared library cannot be referenced
8526 before the shared library has been linked with the program (this
8527 happens after you type ``run'' and before the function main() is entered).
8528 At any time after this linking (including when examining core files
8529 from dynamically linked programs), gdb reads the symbols from each
8530 shared library when you type the ``sharedlibrary'' command.
8531 It can be abbreviated ``share''.
8533 sharedlibrary REGEXP: Load shared object library symbols for files
8534 matching a unix regular expression. No argument
8535 indicates to load symbols for all shared libraries.
8537 info sharedlibrary: Status of loaded shared libraries.
8542 A watchpoint stops execution of a program whenever the value of an
8543 expression changes. Checking for this slows down execution
8544 tremendously whenever you are in the scope of the expression, but is
8545 quite useful for catching tough ``bit-spreader'' or pointer misuse
8546 problems. Some machines such as the 386 have hardware for doing this
8547 more quickly, and future versions of gdb will use this hardware.
8549 watch EXP: Set a watchpoint (breakpoint) for an expression.
8551 info watchpoints: Information about your watchpoints.
8553 delete N: Deletes watchpoint number N (same as breakpoints).
8554 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
8555 enable N: Re-enables watchpoint number N (same as breakpoints).
8558 * C++ multiple inheritance
8560 When used with a GCC version 2 compiler, GDB supports multiple inheritance
8563 * C++ exception handling
8565 Gdb now supports limited C++ exception handling. Besides the existing
8566 ability to breakpoint on an exception handler, gdb can breakpoint on
8567 the raising of an exception (before the stack is peeled back to the
8570 catch FOO: If there is a FOO exception handler in the dynamic scope,
8571 set a breakpoint to catch exceptions which may be raised there.
8572 Multiple exceptions (``catch foo bar baz'') may be caught.
8574 info catch: Lists all exceptions which may be caught in the
8575 current stack frame.
8578 * Minor command changes
8580 The command ``call func (arg, arg, ...)'' now acts like the print
8581 command, except it does not print or save a value if the function's result
8582 is void. This is similar to dbx usage.
8584 The ``up'' and ``down'' commands now always print the frame they end up
8585 at; ``up-silently'' and `down-silently'' can be used in scripts to change
8586 frames without printing.
8588 * New directory command
8590 'dir' now adds directories to the FRONT of the source search path.
8591 The path starts off empty. Source files that contain debug information
8592 about the directory in which they were compiled can be found even
8593 with an empty path; Sun CC and GCC include this information. If GDB can't
8594 find your source file in the current directory, type "dir .".
8596 * Configuring GDB for compilation
8598 For normal use, type ``./configure host''. See README or gdb.texinfo
8601 GDB now handles cross debugging. If you are remotely debugging between
8602 two different machines, type ``./configure host -target=targ''.
8603 Host is the machine where GDB will run; targ is the machine
8604 where the program that you are debugging will run.