1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 10
6 * GDB now supports general memory tagging functionality if the underlying
7 architecture supports the proper primitives and hooks. Currently this is
8 enabled only for AArch64 MTE.
12 - Additional information when the inferior crashes with a SIGSEGV caused by
13 a memory tag violation.
15 - A new modifier 'm' for the "x" command, which displays allocation tags for a
16 particular memory range.
18 - Display of memory tag mismatches by "print", for addresses and
19 pointers, if memory tagging is supported by the architecture.
21 * Building GDB now requires GMP (The GNU Multiple Precision Arithmetic
26 ** '-break-insert --qualified' and '-dprintf-insert --qualified'
28 The MI -break-insert and -dprintf-insert commands now support a
29 new "--qualified" option that makes GDB interpret a specified
30 function name as a complete fully-qualified name. This is the
31 equivalent of the CLI's "break -qualified" and "dprintf
34 ** '-break-insert --force-condition' and '-dprintf-insert --force-condition'
36 The MI -break-insert and -dprintf-insert commands now support a
37 '--force-condition' flag to forcibly define a condition even when
38 the condition is invalid at all locations of the breakpoint. This
39 is equivalent to the '-force-condition' flag of the CLI's "break"
42 * GDB now supports core file debugging for x86_64 Cygwin programs.
44 * GDB will now look for the .gdbinit file in a config directory before
45 looking for ~/.gdbinit. The file is searched for in the following
46 locations: $XDG_CONFIG_HOME/gdb/gdbinit, $HOME/.config/gdb/gdbinit,
47 $HOME/.gdbinit. On Apple hosts the search order is instead:
48 $HOME/Library/Preferences/gdb/gdbinit, $HOME/.gdbinit.
50 * GDB now supports fixed point types which are described in DWARF
51 as base types with a fixed-point encoding. Additionally, support
52 for the DW_AT_GNU_numerator and DW_AT_GNU_denominator has also
55 For Ada, this allows support for fixed point types without requiring
56 the use of the GNAT encoding (based on information added to the type's
57 name following a GNAT-specific format).
59 * GDB will now load and process commands from ~/.config/gdb/gdbearlyinit
60 or ~/.gdbearlyinit if these files are present. These files are
61 processed earlier than any of the other initialization files and
62 can affect parts of GDB's startup that previously had already been
63 completed before the initialization files were read, for example
64 styling of the initial GDB greeting.
66 * GDB now has two new options "--early-init-command" and
67 "--early-init-eval-command" with corresponding short options "-eix"
68 and "-eiex" that allow options (that would normally appear in a
69 gdbearlyinit file) to be passed on the command line.
75 Control the display of debug output about GDB's event loop.
77 set print memory-tag-violations
78 show print memory-tag-violations
79 Control whether to display additional information about memory tag violations
80 when printing pointers and addresses. Architecture support for memory
81 tagging is required for this option to have an effect.
83 maintenance flush symbol-cache
84 maintenance flush register-cache
85 These new commands are equivalent to the already existing commands
86 'maintenance flush-symbol-cache' and 'flushregs' respectively.
88 maintenance flush dcache
89 A new command to flush the dcache.
91 maintenance info target-sections
92 Print GDB's internal target sections table.
94 memory-tag show-logical-tag POINTER
95 Print the logical tag for POINTER.
96 memory-tag with-logical-tag POINTER TAG
97 Print POINTER with logical tag TAG.
98 memory-tag show-allocation-tag ADDRESS
99 Print the allocation tag for ADDRESS.
100 memory-tag set-allocation-tag ADDRESS LENGTH TAGS
101 Set the allocation tag for [ADDRESS, ADDRESS + LENGTH) to TAGS.
102 memory-tag check POINTER
103 Validate that POINTER's logical tag matches the allocation tag.
105 set startup-quietly on|off
107 When 'on', this causes GDB to act as if "-silent" were passed on the
108 command line. This command needs to be added to an early
109 initialization file (e.g. ~/.config/gdb/gdbearlyinit) in order to
112 set print type hex on|off
114 When 'on', the 'ptype' command uses hexadecimal notation to print sizes
115 and offsets of struct members. When 'off', decimal notation is used.
117 set python ignore-environment on|off
118 show python ignore-environment
119 When 'on', this causes GDB's builtin Python to ignore any
120 environment variables that would otherwise affect how Python
121 behaves. This command needs to be added to an early initialization
122 file (e.g. ~/.config/gdb/gdbearlyinit) in order to affect GDB.
124 set python dont-write-bytecode auto|on|off
125 show python dont-write-bytecode
126 When 'on', this causes GDB's builtin Python to not write any
127 byte-code (.pyc files) to disk. This command needs to be added to
128 an early initialization file (e.g. ~/.config/gdb/gdbearlyinit) in
129 order to affect GDB. When 'off' byte-code will always be written.
130 When set to 'auto' (the default) Python will check the
131 PYTHONDONTWRITEBYTECODE environment variable.
135 break [PROBE_MODIFIER] [LOCATION] [thread THREADNUM]
136 [-force-condition] [if CONDITION]
137 This command would previously refuse setting a breakpoint if the
138 CONDITION expression is invalid at a location. It now accepts and
139 defines the breakpoint if there is at least one location at which
140 the CONDITION is valid. The locations for which the CONDITION is
141 invalid, are automatically disabled. If CONDITION is invalid at all
142 of the locations, setting the breakpoint is still rejected. However,
143 the '-force-condition' flag can be used in this case for forcing GDB to
144 define the breakpoint, making all the current locations automatically
145 disabled. This may be useful if the user knows the condition will
146 become meaningful at a future location, e.g. due to a shared library
149 condition [-force] N COND
150 The behavior of this command is changed the same way for the 'break'
151 command as explained above. The '-force' flag can be used to force
152 GDB into defining the condition even when COND is invalid for all the
153 current locations of breakpoint N.
156 maintenance flush-symbol-cache
157 These commands are deprecated in favor of the new commands
158 'maintenance flush register-cache' and 'maintenance flush
159 symbol-cache' respectively.
161 set style version foreground COLOR
162 set style version background COLOR
163 set style version intensity VALUE
164 Control the styling of GDB's version number text.
167 When the ID parameter is omitted, then this command prints information
168 about the current inferior. When the ID parameter is present, the
169 behavior of the command is unchanged and have the inferior ID become
170 the current inferior.
172 maintenance info sections
173 The ALLOBJ keyword has been replaced with an -all-objects command
174 line flag. It is now possible to filter which sections are printed
175 even when -all-objects is passed.
177 ptype[/FLAGS] TYPE | EXPRESSION
178 The 'ptype' command has two new flags. When '/x' is set, hexadecimal
179 notation is used when printing sizes and offsets of struct members.
180 When '/d' is set, decimal notation is used when printing sizes and
181 offsets of struct members. Default behavior is given by 'show print
184 * Removed targets and native configurations
186 ARM Symbian arm*-*-symbianelf*
191 Request the remote to send allocation tags for a particular memory range.
193 Request the remote to store the specified allocation tags to the requested
196 *** Changes in GDB 10
198 * There are new feature names for ARC targets: "org.gnu.gdb.arc.core"
199 and "org.gnu.gdb.arc.aux". The old names are still supported but
200 must be considered obsolete. They will be deprecated after some
203 * Help and apropos commands will now show the documentation of a
204 command only once, even if that command has one or more aliases.
205 These commands now show the command name, then all of its aliases,
206 and finally the description of the command.
208 * 'help aliases' now shows only the user defined aliases. GDB predefined
209 aliases are shown together with their aliased command.
211 * GDB now supports debuginfod, an HTTP server for distributing ELF/DWARF
212 debugging information as well as source code.
214 When built with debuginfod, GDB can automatically query debuginfod
215 servers for the separate debug files and source code of the executable
218 To build GDB with debuginfod, pass --with-debuginfod to configure (this
219 requires libdebuginfod, the debuginfod client library).
221 debuginfod is distributed with elfutils, starting with version 0.178.
223 You can get the latest version from https://sourceware.org/elfutils.
225 * Multi-target debugging support
227 GDB now supports debugging multiple target connections
228 simultaneously. For example, you can now have each inferior
229 connected to different remote servers running in different machines,
230 or have one inferior debugging a local native process, an inferior
231 debugging a core dump, etc.
233 This support is experimental and comes with some limitations -- you
234 can only resume multiple targets simultaneously if all targets
235 support non-stop mode, and all remote stubs or servers must support
236 the same set of remote protocol features exactly. See also "info
237 connections" and "add-inferior -no-connection" below, and "maint set
238 target-non-stop" in the user manual.
240 * New features in the GDB remote stub, GDBserver
242 ** GDBserver is now supported on ARC GNU/Linux.
244 ** GDBserver is now supported on RISC-V GNU/Linux.
246 ** GDBserver no longer supports these host triplets:
257 i[34567]86-*-mingw32ce*
259 * Debugging MS-Windows processes now sets $_exitsignal when the
260 inferior is terminated by a signal, instead of setting $_exitcode.
262 * Multithreaded symbol loading has now been enabled by default on systems
263 that support it (see entry for GDB 9, below), providing faster
264 performance for programs with many symbols.
266 * The $_siginfo convenience variable now also works on Windows targets,
267 and will display the EXCEPTION_RECORD of the last handled exception.
269 * TUI windows can now be arranged horizontally.
271 * The command history filename can now be set to the empty string
272 either using 'set history filename' or by setting 'GDBHISTFILE=' in
273 the environment. The effect of setting this filename to the empty
274 string is that GDB will not try to load any previous command
277 * On Windows targets, it is now possible to debug 32-bit programs with a
282 set exec-file-mismatch -- Set exec-file-mismatch handling (ask|warn|off).
283 show exec-file-mismatch -- Show exec-file-mismatch handling (ask|warn|off).
284 Set or show the option 'exec-file-mismatch'. When GDB attaches to a
285 running process, this new option indicates whether to detect
286 a mismatch between the current executable file loaded by GDB and the
287 executable file used to start the process. If 'ask', the default,
288 display a warning and ask the user whether to load the process
289 executable file; if 'warn', just display a warning; if 'off', don't
290 attempt to detect a mismatch.
292 tui new-layout NAME WINDOW WEIGHT [WINDOW WEIGHT]...
293 Define a new TUI layout, specifying its name and the windows that
296 maintenance print xml-tdesc [FILE]
297 Prints the current target description as an XML document. If the
298 optional FILE is provided (which is an XML target description) then
299 the target description is read from FILE into GDB, and then
302 maintenance print core-file-backed-mappings
303 Prints file-backed mappings loaded from a core file's note section.
304 Output is expected to be similar to that of "info proc mappings".
306 set debug fortran-array-slicing on|off
307 show debug fortran-array-slicing
308 Print debugging when taking slices of Fortran arrays.
310 set fortran repack-array-slices on|off
311 show fortran repack-array-slices
312 When taking slices from Fortran arrays and strings, if the slice is
313 non-contiguous within the original value then, when this option is
314 on, the new value will be repacked into a single contiguous value.
315 When this option is off, then the value returned will consist of a
316 descriptor that describes the slice within the memory of the
317 original parent value.
321 alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
322 The alias command can now specify default args for an alias.
323 GDB automatically prepends the alias default args to the argument list
324 provided explicitly by the user.
325 For example, to have a backtrace with full details, you can define
327 'alias bt_ALL = backtrace -entry-values both -frame-arg all
328 -past-main -past-entry -full'.
329 Alias default arguments can also use a set of nested 'with' commands,
330 e.g. 'alias pp10 = with print pretty -- with print elem 10 -- print'
331 defines the alias pp10 that will pretty print a maximum of 10 elements
332 of the given expression (if the expression is an array).
336 GNU/Linux/RISC-V (gdbserver) riscv*-*-linux*
341 ** gdb.register_window_type can be used to implement new TUI windows
344 ** Dynamic types can now be queried. gdb.Type has a new attribute,
345 "dynamic", and gdb.Type.sizeof can be None for a dynamic type. A
346 field of a dynamic type may have None for its "bitpos" attribute
349 ** Commands written in Python can be in the "TUI" help class by
350 registering with the new constant gdb.COMMAND_TUI.
352 ** New method gdb.PendingFrame.architecture () to retrieve the
353 architecture of the pending frame.
355 ** New gdb.Architecture.registers method that returns a
356 gdb.RegisterDescriptorIterator object, an iterator that returns
357 gdb.RegisterDescriptor objects. The new RegisterDescriptor is a
358 way to query the registers available for an architecture.
360 ** New gdb.Architecture.register_groups method that returns a
361 gdb.RegisterGroupIterator object, an iterator that returns
362 gdb.RegisterGroup objects. The new RegisterGroup is a way to
363 discover the available register groups.
367 ** GDB can now be built with GNU Guile 3.0 and 2.2 in addition to 2.0.
369 ** Procedures 'memory-port-read-buffer-size',
370 'set-memory-port-read-buffer-size!', 'memory-port-write-buffer-size',
371 and 'set-memory-port-write-buffer-size!' are deprecated. When
372 using Guile 2.2 and later, users who need to control the size of
373 a memory port's internal buffer can use the 'setvbuf' procedure.
377 * 'thread-exited' event is now available in the annotations interface.
379 * New built-in convenience variables $_gdb_major and $_gdb_minor
380 provide the GDB version. They are handy for conditionally using
381 features available only in or since specific GDB versions, in
382 scripts that should work error-free with many different versions,
383 such as in system-wide init files.
385 * New built-in convenience functions $_gdb_setting, $_gdb_setting_str,
386 $_gdb_maint_setting and $_gdb_maint_setting_str provide access to values
387 of the GDB settings and the GDB maintenance settings. They are handy
388 for changing the logic of user defined commands depending on the
389 current GDB settings.
391 * GDB now supports Thread Local Storage (TLS) variables on several
392 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
393 architectures require kernel changes. TLS is not yet supported for
394 amd64 and i386 process core dumps.
396 * Support for Pointer Authentication (PAC) on AArch64 Linux. Return
397 addresses that required unmasking are shown in the backtrace with the
400 * Two new convenience functions $_cimag and $_creal that extract the
401 imaginary and real parts respectively from complex numbers.
403 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
404 provide the exitcode or exit status of the shell commands launched by
405 GDB commands such as "shell", "pipe" and "make".
407 * The command define-prefix can now define user defined prefix commands.
408 User defined commands can now be defined using these user defined prefix
411 * Command names can now use the . character.
413 * The RX port now supports XML target descriptions.
415 * GDB now shows the Ada task names at more places, e.g. in task switching
418 * GDB can now be compiled with Python 3 on Windows.
420 * New convenience variable $_ada_exception holds the address of the
421 Ada exception being thrown. This is set by Ada-related catchpoints.
423 * GDB can now place breakpoints on nested functions and subroutines in
424 Fortran code. The '::' operator can be used between parent and
425 child scopes when placing breakpoints, for example:
427 (gdb) break outer_function::inner_function
429 The 'outer_function::' prefix is only needed if 'inner_function' is
430 not visible in the current scope.
432 * In addition to the system-wide gdbinit file, if configured with
433 --with-system-gdbinit-dir, GDB will now also load files in that directory
434 as system gdbinit files, unless the -nx or -n flag is provided. Files
435 with extensions .gdb, .py and .scm are supported as long as GDB was
436 compiled with support for that language.
438 * GDB now supports multithreaded symbol loading for higher performance.
439 This feature is still in testing, so it is disabled by default. You
440 can turn it on using 'maint set worker-threads unlimited'.
444 ** The gdb.Value type has a new method 'format_string' which returns a
445 string representing the value. The formatting is controlled by the
446 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
447 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
448 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
450 ** gdb.Type has a new property 'objfile' which returns the objfile the
453 ** The frame information printed by the python frame filtering code
454 is now consistent with what the 'backtrace' command prints when
455 there are no filters, or when the 'backtrace' '-no-filters' option
458 ** The new function gdb.lookup_static_symbol can be used to look up
459 symbols with static linkage.
461 ** The new function gdb.lookup_static_symbols can be used to look up
462 all static symbols with static linkage.
464 ** gdb.Objfile has new methods 'lookup_global_symbol' and
465 'lookup_static_symbol' to lookup a symbol from this objfile only.
467 ** gdb.Block now supports the dictionary syntax for accessing symbols in
468 this block (e.g. block['local_variable']).
472 | [COMMAND] | SHELL_COMMAND
473 | -d DELIM COMMAND DELIM SHELL_COMMAND
474 pipe [COMMAND] | SHELL_COMMAND
475 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
476 Executes COMMAND and sends its output to SHELL_COMMAND.
477 With no COMMAND, repeat the last executed command
478 and send its output to SHELL_COMMAND.
480 define-prefix COMMAND
481 Define or mark a command as a user-defined prefix command.
483 with SETTING [VALUE] [-- COMMAND]
484 w SETTING [VALUE] [-- COMMAND]
485 Temporarily set SETTING, run COMMAND, and restore SETTING.
486 Usage: with SETTING -- COMMAND
487 With no COMMAND, repeats the last executed command.
488 SETTING is any GDB setting you can change with the "set"
489 subcommands. For example, 'with language c -- print someobj'
490 temporarily switches to the C language in order to print someobj.
491 Settings can be combined: 'w lang c -- w print elements unlimited --
492 usercmd' switches to the C language and runs usercmd with no limit
493 of array elements to print.
495 maint with SETTING [VALUE] [-- COMMAND]
496 Like "with", but works with "maintenance set" settings.
498 set may-call-functions [on|off]
499 show may-call-functions
500 This controls whether GDB will attempt to call functions in
501 the program, such as with expressions in the print command. It
502 defaults to on. Calling functions in the program being debugged
503 can have undesired side effects. It is now possible to forbid
504 such function calls. If function calls are forbidden, GDB will throw
505 an error when a command (such as print expression) calls a function
508 set print finish [on|off]
510 This controls whether the `finish' command will display the value
511 that is returned by the current function. When `off', the value is
512 still entered into the value history, but it is not printed. The
517 Allows deeply nested structures to be simplified when printing by
518 replacing deeply nested parts (beyond the max-depth) with ellipses.
519 The default max-depth is 20, but this can be set to unlimited to get
520 the old behavior back.
522 set print raw-values [on|off]
523 show print raw-values
524 By default, GDB applies the enabled pretty printers when printing a
525 value. This allows to ignore the enabled pretty printers for a series
526 of commands. The default is 'off'.
528 set logging debugredirect [on|off]
529 By default, GDB debug output will go to both the terminal and the logfile.
530 Set if you want debug output to go only to the log file.
532 set style title foreground COLOR
533 set style title background COLOR
534 set style title intensity VALUE
535 Control the styling of titles.
537 set style highlight foreground COLOR
538 set style highlight background COLOR
539 set style highlight intensity VALUE
540 Control the styling of highlightings.
542 maint set worker-threads
543 maint show worker-threads
544 Control the number of worker threads that can be used by GDB. The
545 default is 0. "unlimited" lets GDB choose a number that is
546 reasonable. Currently worker threads are only used when demangling
547 the names of linker symbols.
549 set style tui-border foreground COLOR
550 set style tui-border background COLOR
551 Control the styling of TUI borders.
553 set style tui-active-border foreground COLOR
554 set style tui-active-border background COLOR
555 Control the styling of the active TUI border.
557 maint set test-settings KIND
558 maint show test-settings KIND
559 A set of commands used by the testsuite for exercising the settings
562 maint set tui-resize-message [on|off]
563 maint show tui-resize-message
564 Control whether GDB prints a message each time the terminal is
565 resized when in TUI mode. This is primarily useful for testing the
568 set print frame-info [short-location|location|location-and-address
569 |source-and-location|source-line|auto]
570 show print frame-info
571 This controls what frame information is printed by the commands printing
572 a frame. This setting will e.g. influence the behaviour of 'backtrace',
573 'frame', 'stepi'. The python frame filtering also respect this setting.
574 The 'backtrace' '-frame-info' option can override this global setting.
576 set tui compact-source
577 show tui compact-source
579 Enable the "compact" display mode for the TUI source window. The
580 compact display uses only as much space as is needed for the line
581 numbers in the current file, and only a single space to separate the
582 line numbers from the source.
584 info modules [-q] [REGEXP]
585 Return a list of Fortran modules matching REGEXP, or all modules if
588 info module functions [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
589 Return a list of functions within all modules, grouped by module.
590 The list of functions can be restricted with the optional regular
591 expressions. MODULE_REGEXP matches against the module name,
592 TYPE_REGEXP matches against the function type signature, and REGEXP
593 matches against the function name.
595 info module variables [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
596 Return a list of variables within all modules, grouped by module.
597 The list of variables can be restricted with the optional regular
598 expressions. MODULE_REGEXP matches against the module name,
599 TYPE_REGEXP matches against the variable type, and REGEXP matches
600 against the variable name.
602 set debug remote-packet-max-chars
603 show debug remote-packet-max-chars
604 Controls the number of characters to output in a remote packet when using
606 The default is 512 bytes.
609 Lists the target connections currently in use.
614 The "help" command uses the title style to enhance the
615 readibility of its output by styling the classes and
619 Similarly to "help", the "apropos" command also uses the
620 title style for the command names. "apropos" accepts now
621 a flag "-v" (verbose) to show the full documentation
622 of matching commands and to use the highlight style to mark
623 the documentation parts matching REGEXP.
627 The GDB printf and eval commands can now print C-style and Ada-style
628 string convenience variables without calling functions in the program.
629 This allows to do formatted printing of strings without having
630 a running inferior, or when debugging a core dump.
632 info sources [-dirname | -basename] [--] [REGEXP]
633 This command has now optional arguments to only print the files
634 whose names match REGEXP. The arguments -dirname and -basename
635 allow to restrict matching respectively to the dirname and basename
639 The "show style" and its subcommands are now styling
640 a style name in their output using its own style, to help
641 the user visualize the different styles.
643 set print frame-arguments
644 The new value 'presence' indicates to only indicate the presence of
645 arguments using ..., instead of printing argument names and values.
647 set print raw-frame-arguments
648 show print raw-frame-arguments
650 These commands replace the similarly-named "set/show print raw
651 frame-arguments" commands (now with a dash instead of a space). The
652 old commands are now deprecated and may be removed in a future
655 add-inferior [-no-connection]
656 The add-inferior command now supports a "-no-connection" flag that
657 makes the new inferior start with no target connection associated.
658 By default, the new inferior inherits the target connection of the
659 current inferior. See also "info connections".
662 This command's output now includes a new "Connection" column
663 indicating which target connection an inferior is bound to. See
664 "info connections" above.
666 maint test-options require-delimiter
667 maint test-options unknown-is-error
668 maint test-options unknown-is-operand
669 maint show test-options-completion-result
670 Commands used by the testsuite to validate the command options
673 focus, winheight, +, -, >, <
674 These commands are now case-sensitive.
676 * New command options, command completion
678 GDB now has a standard infrastructure to support dash-style command
679 options ('-OPT'). One benefit is that commands that use it can
680 easily support completion of command line arguments. Try "CMD
681 -[TAB]" or "help CMD" to find options supported by a command. Over
682 time, we intend to migrate most commands to this infrastructure. A
683 number of commands got support for new command options in this
686 ** The "print" and "compile print" commands now support a number of
687 options that allow overriding relevant global print settings as
688 set by "set print" subcommands:
692 -array-indexes [on|off]
693 -elements NUMBER|unlimited
698 -repeats NUMBER|unlimited
699 -static-members [on|off]
704 Note that because the "print"/"compile print" commands accept
705 arbitrary expressions which may look like options (including
706 abbreviations), if you specify any command option, then you must
707 use a double dash ("--") to mark the end of argument processing.
709 ** The "backtrace" command now supports a number of options that
710 allow overriding relevant global print settings as set by "set
711 backtrace" and "set print" subcommands:
713 -entry-values no|only|preferred|if-needed|both|compact|default
714 -frame-arguments all|scalars|none
715 -raw-frame-arguments [on|off]
716 -frame-info auto|source-line|location|source-and-location
717 |location-and-address|short-location
721 In addition, the full/no-filters/hide qualifiers are now also
722 exposed as command options too:
728 ** The "frame apply", "tfaas" and "faas" commands similarly now
729 support the following options:
734 ** The new "info sources" options -dirname and -basename options
735 are using the standard '-OPT' infrastructure.
737 All options above can also be abbreviated. The argument of boolean
738 (on/off) options can be 0/1 too, and also the argument is assumed
739 "on" if omitted. This allows writing compact command invocations,
742 (gdb) p -ra -p -o 0 -- *myptr
744 The above is equivalent to:
746 (gdb) print -raw-values -pretty -object off -- *myptr
748 ** The "info types" command now supports the '-q' flag to disable
749 printing of some header information in a similar fashion to "info
750 variables" and "info functions".
752 ** The "info variables", "info functions", and "whereis" commands
753 now take a '-n' flag that excludes non-debug symbols (symbols
754 from the symbol table, not from the debug info such as DWARF)
757 * Completion improvements
759 ** GDB can now complete the options of the "thread apply all" and
760 "taas" commands, and their "-ascending" option can now be
763 ** GDB can now complete the options of the "info threads", "info
764 functions", "info variables", "info locals", and "info args"
767 ** GDB can now complete the options of the "compile file" and
768 "compile code" commands. The "compile file" command now
769 completes on filenames.
771 ** GDB can now complete the backtrace command's
772 "full/no-filters/hide" qualifiers.
774 * In settings, you can now abbreviate "unlimited".
776 E.g., "set print elements u" is now equivalent to "set print
782 This lists all the possible completions for the rest of the line, if it
783 were to be given as a command itself. This is intended for use by MI
784 frontends in cases when separate CLI and MI channels cannot be used.
786 -catch-throw, -catch-rethrow, and -catch-catch
787 These can be used to catch C++ exceptions in a similar fashion to
788 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
790 -symbol-info-functions, -symbol-info-types, and -symbol-info-variables
791 These commands are the MI equivalent of the CLI commands 'info
792 functions', 'info types', and 'info variables' respectively.
794 -symbol-info-modules, this is the MI equivalent of the CLI 'info
797 -symbol-info-module-functions and -symbol-info-module-variables.
798 These commands are the MI equivalent of the CLI commands 'info
799 module functions' and 'info module variables'.
803 ** The default version of the MI interpreter is now 3 (-i=mi3).
805 ** The output of information about multi-location breakpoints (which is
806 syntactically incorrect in MI 2) has changed in MI 3. This affects
807 the following commands and events:
811 - =breakpoint-created
812 - =breakpoint-modified
814 The -fix-multi-location-breakpoint-output command can be used to enable
815 this behavior with previous MI versions.
817 ** Backtraces and frames include a new optional field addr_flags which is
818 given after the addr field. On AArch64 this contains PAC if the address
819 has been masked in the frame. On all other targets the field is not
824 The testsuite now creates the files gdb.cmd (containing the arguments
825 used to launch GDB) and gdb.in (containing all the commands sent to
826 GDB) in the output directory for each test script. Multiple invocations
827 are appended with .1, .2, .3 etc.
829 * Building GDB and GDBserver now requires GNU make >= 3.82.
831 Using another implementation of the make program or an earlier version of
832 GNU make to build GDB or GDBserver is not supported.
834 * Building GDB now requires GNU readline >= 7.0.
836 GDB now bundles GNU readline 8.0, but if you choose to use
837 --with-system-readline, only readline >= 7.0 can be used.
839 * The TUI SingleKey keymap is now named "SingleKey". This can be used
840 from .inputrc to bind keys in this keymap. This feature is only
841 available when gdb is built against GNU readline 8.0 or later.
843 * Removed targets and native configurations
845 GDB no longer supports debugging the Cell Broadband Engine. This includes
846 both debugging standalone Cell/B.E. SPU applications and integrated debugging
847 of Cell/B.E. applications that use both the PPU and SPU architectures.
853 * Removed targets and native configurations
855 Solaris 10 i?86-*-solaris2.10, x86_64-*-solaris2.10,
858 *** Changes in GDB 8.3
860 * GDB and GDBserver now support access to additional registers on
861 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
864 * GDB now has experimental support for the compilation and injection of
865 C++ source code into the inferior. This beta release does not include
866 support for several language features, such as templates, constructors,
869 This feature requires GCC 7.1 or higher built with libcp1.so
872 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
873 can be passed using the '[ADDRESS]:PORT' notation, or the regular
874 'ADDRESS:PORT' method.
876 * DWARF index cache: GDB can now automatically save indices of DWARF
877 symbols on disk to speed up further loading of the same binaries.
879 * Ada task switching is now supported on aarch64-elf targets when
880 debugging a program using the Ravenscar Profile. For more information,
881 see the "Tasking Support when using the Ravenscar Profile" section
882 in the GDB user manual.
884 * GDB in batch mode now exits with status 1 if the last command to be
887 * The RISC-V target now supports target descriptions.
889 * System call catchpoints now support system call aliases on FreeBSD.
890 When the ABI of a system call changes in FreeBSD, this is
891 implemented by leaving a compatibility system call using the old ABI
892 at the existing number and allocating a new system call number for
893 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
894 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
895 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
896 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
897 so that a system call catchpoint for the 'kevent' system call will
898 catch invocations of both the 'kevent' and 'freebsd11_kevent'
899 binaries. This ensures that 'kevent' system calls are caught for
900 binaries using either the old or new ABIs.
902 * Terminal styling is now available for the CLI and the TUI. GNU
903 Source Highlight can additionally be used to provide styling of
904 source code snippets. See the "set style" commands, below, for more
907 * Removed support for old demangling styles arm, edg, gnu, hp and
912 set debug compile-cplus-types
913 show debug compile-cplus-types
914 Control the display of debug output about type conversion in the
915 C++ compile feature. Commands have no effect while compiling
920 Control whether debug output about files/functions skipping is
923 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
924 Apply a command to some frames.
925 FLAG arguments allow to control what output to produce and how to handle
926 errors raised when applying COMMAND to a frame.
929 Apply a command to all threads (ignoring errors and empty output).
930 Shortcut for 'thread apply all -s COMMAND'.
933 Apply a command to all frames (ignoring errors and empty output).
934 Shortcut for 'frame apply all -s COMMAND'.
937 Apply a command to all frames of all threads (ignoring errors and empty
939 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
941 maint set dwarf unwinders (on|off)
942 maint show dwarf unwinders
943 Control whether DWARF unwinders can be used.
946 Display a list of open files for a process.
950 Changes to the "frame", "select-frame", and "info frame" CLI commands.
951 These commands all now take a frame specification which
952 is either a frame level, or one of the keywords 'level', 'address',
953 'function', or 'view' followed by a parameter. Selecting a frame by
954 address, or viewing a frame outside the current backtrace now
955 requires the use of a keyword. Selecting a frame by level is
956 unchanged. The MI comment "-stack-select-frame" is unchanged.
958 target remote FILENAME
959 target extended-remote FILENAME
960 If FILENAME is a Unix domain socket, GDB will attempt to connect
961 to this socket instead of opening FILENAME as a character device.
963 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
964 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
965 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
966 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
967 These commands can now print only the searched entities
968 matching the provided regexp(s), giving a condition
969 on the entity names or entity types. The flag -q disables
970 printing headers or informations messages.
976 These commands now determine the syntax for the shown entities
977 according to the language chosen by `set language'. In particular,
978 `set language auto' means to automatically choose the language of
981 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
982 The 'thread apply' command accepts new FLAG arguments.
983 FLAG arguments allow to control what output to produce and how to handle
984 errors raised when applying COMMAND to a thread.
986 set tui tab-width NCHARS
987 show tui tab-width NCHARS
988 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
990 set style enabled [on|off]
992 Enable or disable terminal styling. Styling is enabled by default
993 on most hosts, but disabled by default when in batch mode.
995 set style sources [on|off]
997 Enable or disable source code styling. Source code styling is
998 enabled by default, but only takes effect if styling in general is
999 enabled, and if GDB was linked with GNU Source Highlight.
1001 set style filename foreground COLOR
1002 set style filename background COLOR
1003 set style filename intensity VALUE
1004 Control the styling of file names.
1006 set style function foreground COLOR
1007 set style function background COLOR
1008 set style function intensity VALUE
1009 Control the styling of function names.
1011 set style variable foreground COLOR
1012 set style variable background COLOR
1013 set style variable intensity VALUE
1014 Control the styling of variable names.
1016 set style address foreground COLOR
1017 set style address background COLOR
1018 set style address intensity VALUE
1019 Control the styling of addresses.
1023 ** The '-data-disassemble' MI command now accepts an '-a' option to
1024 disassemble the whole function surrounding the given program
1025 counter value or function name. Support for this feature can be
1026 verified by using the "-list-features" command, which should
1027 contain "data-disassemble-a-option".
1029 ** Command responses and notifications that include a frame now include
1030 the frame's architecture in a new "arch" attribute.
1032 * New native configurations
1034 GNU/Linux/RISC-V riscv*-*-linux*
1035 FreeBSD/riscv riscv*-*-freebsd*
1039 GNU/Linux/RISC-V riscv*-*-linux*
1040 CSKY ELF csky*-*-elf
1041 CSKY GNU/LINUX csky*-*-linux
1042 FreeBSD/riscv riscv*-*-freebsd*
1044 GNU/Linux/OpenRISC or1k*-*-linux*
1048 GDB no longer supports native debugging on versions of MS-Windows
1053 ** GDB no longer supports Python versions less than 2.6.
1055 ** The gdb.Inferior type has a new 'progspace' property, which is the program
1056 space associated to that inferior.
1058 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
1059 of objfiles associated to that program space.
1061 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
1062 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
1065 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
1066 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
1067 correct and did not work properly.
1069 ** The gdb.Value type has a new constructor, which is used to construct a
1070 gdb.Value from a Python buffer object and a gdb.Type.
1076 Enable or disable the undefined behavior sanitizer. This is
1077 disabled by default, but passing --enable-ubsan=yes or
1078 --enable-ubsan=auto to configure will enable it. Enabling this can
1079 cause a performance penalty. The undefined behavior sanitizer was
1080 first introduced in GCC 4.9.
1082 *** Changes in GDB 8.2
1084 * The 'set disassembler-options' command now supports specifying options
1085 for the MIPS target.
1087 * The 'symbol-file' command now accepts an '-o' option to add a relative
1088 offset to all sections.
1090 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
1091 a relative offset to all sections, but it allows to override the load
1092 address of individual sections using '-s'.
1094 * The 'add-symbol-file' command no longer requires the second argument
1095 (address of the text section).
1097 * The endianness used with the 'set endian auto' mode in the absence of
1098 an executable selected for debugging is now the last endianness chosen
1099 either by one of the 'set endian big' and 'set endian little' commands
1100 or by inferring from the last executable used, rather than the startup
1103 * The pager now allows a "c" response, meaning to disable the pager
1104 for the rest of the current command.
1106 * The commands 'info variables/functions/types' now show the source line
1107 numbers of symbol definitions when available.
1109 * 'info proc' now works on running processes on FreeBSD systems and core
1110 files created on FreeBSD systems.
1112 * C expressions can now use _Alignof, and C++ expressions can now use
1115 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
1116 the vector length while the process is running.
1122 Control display of debugging info regarding the FreeBSD native target.
1124 set|show varsize-limit
1125 This new setting allows the user to control the maximum size of Ada
1126 objects being printed when those objects have a variable type,
1127 instead of that maximum size being hardcoded to 65536 bytes.
1129 set|show record btrace cpu
1130 Controls the processor to be used for enabling errata workarounds for
1131 branch trace decode.
1133 maint check libthread-db
1134 Run integrity checks on the current inferior's thread debugging
1137 maint set check-libthread-db (on|off)
1138 maint show check-libthread-db
1139 Control whether to run integrity checks on inferior specific thread
1140 debugging libraries as they are loaded. The default is not to
1141 perform such checks.
1145 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
1147 ** The commands attached to a breakpoint can be set by assigning to
1148 the breakpoint's "commands" field.
1150 ** gdb.execute can now execute multi-line gdb commands.
1152 ** The new functions gdb.convenience_variable and
1153 gdb.set_convenience_variable can be used to get and set the value
1154 of convenience variables.
1156 ** A gdb.Parameter will no longer print the "set" help text on an
1157 ordinary "set"; instead by default a "set" will be silent unless
1158 the get_set_string method returns a non-empty string.
1162 RiscV ELF riscv*-*-elf
1164 * Removed targets and native configurations
1166 m88k running OpenBSD m88*-*-openbsd*
1167 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
1168 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
1169 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
1171 * Aarch64/Linux hardware watchpoints improvements
1173 Hardware watchpoints on unaligned addresses are now properly
1174 supported when running Linux kernel 4.10 or higher: read and access
1175 watchpoints are no longer spuriously missed, and all watchpoints
1176 lengths between 1 and 8 bytes are supported. On older kernels,
1177 watchpoints set on unaligned addresses are no longer missed, with
1178 the tradeoff that there is a possibility of false hits being
1183 --enable-codesign=CERT
1184 This can be used to invoke "codesign -s CERT" after building gdb.
1185 This option is useful on macOS, where code signing is required for
1186 gdb to work properly.
1188 --disable-gdbcli has been removed
1189 This is now silently accepted, but does nothing.
1191 *** Changes in GDB 8.1
1193 * GDB now supports dynamically creating arbitrary register groups specified
1194 in XML target descriptions. This allows for finer grain grouping of
1195 registers on systems with a large amount of registers.
1197 * The 'ptype' command now accepts a '/o' flag, which prints the
1198 offsets and sizes of fields in a struct, like the pahole(1) tool.
1200 * New "--readnever" command line option instructs GDB to not read each
1201 symbol file's symbolic debug information. This makes startup faster
1202 but at the expense of not being able to perform symbolic debugging.
1203 This option is intended for use cases where symbolic debugging will
1204 not be used, e.g., when you only need to dump the debuggee's core.
1206 * GDB now uses the GNU MPFR library, if available, to emulate target
1207 floating-point arithmetic during expression evaluation when the target
1208 uses different floating-point formats than the host. At least version
1209 3.1 of GNU MPFR is required.
1211 * GDB now supports access to the guarded-storage-control registers and the
1212 software-based guarded-storage broadcast control registers on IBM z14.
1214 * On Unix systems, GDB now supports transmitting environment variables
1215 that are to be set or unset to GDBserver. These variables will
1216 affect the environment to be passed to the remote inferior.
1218 To inform GDB of environment variables that are to be transmitted to
1219 GDBserver, use the "set environment" command. Only user set
1220 environment variables are sent to GDBserver.
1222 To inform GDB of environment variables that are to be unset before
1223 the remote inferior is started by the GDBserver, use the "unset
1224 environment" command.
1226 * Completion improvements
1228 ** GDB can now complete function parameters in linespecs and
1229 explicit locations without quoting. When setting breakpoints,
1230 quoting around functions names to help with TAB-completion is
1231 generally no longer necessary. For example, this now completes
1234 (gdb) b function(in[TAB]
1235 (gdb) b function(int)
1237 Related, GDB is no longer confused with completing functions in
1238 C++ anonymous namespaces:
1241 (gdb) b (anonymous namespace)::[TAB][TAB]
1242 (anonymous namespace)::a_function()
1243 (anonymous namespace)::b_function()
1245 ** GDB now has much improved linespec and explicit locations TAB
1246 completion support, that better understands what you're
1247 completing and offers better suggestions. For example, GDB no
1248 longer offers data symbols as possible completions when you're
1249 setting a breakpoint.
1251 ** GDB now TAB-completes label symbol names.
1253 ** The "complete" command now mimics TAB completion accurately.
1255 * New command line options (gcore)
1258 Dump all memory mappings.
1260 * Breakpoints on C++ functions are now set on all scopes by default
1262 By default, breakpoints on functions/methods are now interpreted as
1263 specifying all functions with the given name ignoring missing
1264 leading scopes (namespaces and classes).
1266 For example, assuming a C++ program with symbols named:
1271 both commands "break func()" and "break B::func()" set a breakpoint
1274 You can use the new flag "-qualified" to override this. This makes
1275 GDB interpret the specified function name as a complete
1276 fully-qualified name instead. For example, using the same C++
1277 program, the "break -q B::func" command sets a breakpoint on
1278 "B::func", only. A parameter has been added to the Python
1279 gdb.Breakpoint constructor to achieve the same result when creating
1280 a breakpoint from Python.
1282 * Breakpoints on functions marked with C++ ABI tags
1284 GDB can now set breakpoints on functions marked with C++ ABI tags
1285 (e.g., [abi:cxx11]). See here for a description of ABI tags:
1286 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
1288 Functions with a C++11 abi tag are demangled/displayed like this:
1290 function[abi:cxx11](int)
1293 You can now set a breakpoint on such functions simply as if they had
1296 (gdb) b function(int)
1298 Or if you need to disambiguate between tags, like:
1300 (gdb) b function[abi:other_tag](int)
1302 Tab completion was adjusted accordingly as well.
1306 ** New events gdb.new_inferior, gdb.inferior_deleted, and
1307 gdb.new_thread are emitted. See the manual for further
1308 description of these.
1310 ** A new function, "gdb.rbreak" has been added to the Python API.
1311 This function allows the setting of a large number of breakpoints
1312 via a regex pattern in Python. See the manual for further details.
1314 ** Python breakpoints can now accept explicit locations. See the
1315 manual for a further description of this feature.
1318 * New features in the GDB remote stub, GDBserver
1320 ** GDBserver is now able to start inferior processes with a
1321 specified initial working directory.
1323 The user can set the desired working directory to be used from
1324 GDB using the new "set cwd" command.
1326 ** New "--selftest" command line option runs some GDBserver self
1327 tests. These self tests are disabled in releases.
1329 ** On Unix systems, GDBserver now does globbing expansion and variable
1330 substitution in inferior command line arguments.
1332 This is done by starting inferiors using a shell, like GDB does.
1333 See "set startup-with-shell" in the user manual for how to disable
1334 this from GDB when using "target extended-remote". When using
1335 "target remote", you can disable the startup with shell by using the
1336 new "--no-startup-with-shell" GDBserver command line option.
1338 ** On Unix systems, GDBserver now supports receiving environment
1339 variables that are to be set or unset from GDB. These variables
1340 will affect the environment to be passed to the inferior.
1342 * When catching an Ada exception raised with a message, GDB now prints
1343 the message in the catchpoint hit notification. In GDB/MI mode, that
1344 information is provided as an extra field named "exception-message"
1345 in the *stopped notification.
1347 * Trait objects can now be inspected When debugging Rust code. This
1348 requires compiler support which will appear in Rust 1.24.
1350 * New remote packets
1352 QEnvironmentHexEncoded
1353 Inform GDBserver of an environment variable that is to be passed to
1354 the inferior when starting it.
1357 Inform GDBserver of an environment variable that is to be unset
1358 before starting the remote inferior.
1361 Inform GDBserver that the environment should be reset (i.e.,
1362 user-set environment variables should be unset).
1365 Indicates whether the inferior must be started with a shell or not.
1368 Tell GDBserver that the inferior to be started should use a specific
1371 * The "maintenance print c-tdesc" command now takes an optional
1372 argument which is the file name of XML target description.
1374 * The "maintenance selftest" command now takes an optional argument to
1375 filter the tests to be run.
1377 * The "enable", and "disable" commands now accept a range of
1378 breakpoint locations, e.g. "enable 1.3-5".
1383 Set and show the current working directory for the inferior.
1385 set|show compile-gcc
1386 Set and show compilation command used for compiling and injecting code
1387 with the 'compile' commands.
1389 set debug separate-debug-file
1390 show debug separate-debug-file
1391 Control the display of debug output about separate debug file search.
1393 set dump-excluded-mappings
1394 show dump-excluded-mappings
1395 Control whether mappings marked with the VM_DONTDUMP flag should be
1396 dumped when generating a core file.
1398 maint info selftests
1399 List the registered selftests.
1402 Start the debugged program stopping at the first instruction.
1405 Control display of debugging messages related to OpenRISC targets.
1407 set|show print type nested-type-limit
1408 Set and show the limit of nesting level for nested types that the
1409 type printer will show.
1411 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
1414 * Safer/improved support for debugging with no debug info
1416 GDB no longer assumes functions with no debug information return
1419 This means that GDB now refuses to call such functions unless you
1420 tell it the function's type, by either casting the call to the
1421 declared return type, or by casting the function to a function
1422 pointer of the right type, and calling that:
1424 (gdb) p getenv ("PATH")
1425 'getenv' has unknown return type; cast the call to its declared return type
1426 (gdb) p (char *) getenv ("PATH")
1427 $1 = 0x7fffffffe "/usr/local/bin:/"...
1428 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
1429 $2 = 0x7fffffffe "/usr/local/bin:/"...
1431 Similarly, GDB no longer assumes that global variables with no debug
1432 info have type 'int', and refuses to print the variable's value
1433 unless you tell it the variable's type:
1436 'var' has unknown type; cast it to its declared type
1440 * New native configurations
1442 FreeBSD/aarch64 aarch64*-*-freebsd*
1443 FreeBSD/arm arm*-*-freebsd*
1447 FreeBSD/aarch64 aarch64*-*-freebsd*
1448 FreeBSD/arm arm*-*-freebsd*
1449 OpenRISC ELF or1k*-*-elf
1451 * Removed targets and native configurations
1453 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
1455 *** Changes in GDB 8.0
1457 * GDB now supports access to the PKU register on GNU/Linux. The register is
1458 added by the Memory Protection Keys for Userspace feature which will be
1459 available in future Intel CPUs.
1461 * GDB now supports C++11 rvalue references.
1465 ** New functions to start, stop and access a running btrace recording.
1466 ** Rvalue references are now supported in gdb.Type.
1468 * GDB now supports recording and replaying rdrand and rdseed Intel 64
1471 * Building GDB and GDBserver now requires a C++11 compiler.
1473 For example, GCC 4.8 or later.
1475 It is no longer possible to build GDB or GDBserver with a C
1476 compiler. The --disable-build-with-cxx configure option has been
1479 * Building GDB and GDBserver now requires GNU make >= 3.81.
1481 It is no longer supported to build GDB or GDBserver with another
1482 implementation of the make program or an earlier version of GNU make.
1484 * Native debugging on MS-Windows supports command-line redirection
1486 Command-line arguments used for starting programs on MS-Windows can
1487 now include redirection symbols supported by native Windows shells,
1488 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
1489 as "run", "start", and "set args", as well as the corresponding MI
1492 * Support for thread names on MS-Windows.
1494 GDB now catches and handles the special exception that programs
1495 running on MS-Windows use to assign names to threads in the
1498 * Support for Java programs compiled with gcj has been removed.
1500 * User commands now accept an unlimited number of arguments.
1501 Previously, only up to 10 was accepted.
1503 * The "eval" command now expands user-defined command arguments.
1505 This makes it easier to process a variable number of arguments:
1510 eval "print $arg%d", $i
1515 * Target descriptions can now describe registers for sparc32 and sparc64.
1517 * GDB now supports DWARF version 5 (debug information format).
1518 Its .debug_names index is not yet supported.
1520 * New native configurations
1522 FreeBSD/mips mips*-*-freebsd
1526 Synopsys ARC arc*-*-elf32
1527 FreeBSD/mips mips*-*-freebsd
1529 * Removed targets and native configurations
1531 Alpha running FreeBSD alpha*-*-freebsd*
1532 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
1537 Erases all the flash memory regions reported by the target.
1539 maint print arc arc-instruction address
1540 Print internal disassembler information about instruction at a given address.
1544 set disassembler-options
1545 show disassembler-options
1546 Controls the passing of target specific information to the disassembler.
1547 If it is necessary to specify more than one disassembler option then
1548 multiple options can be placed together into a comma separated list.
1549 The default value is the empty string. Currently, the only supported
1550 targets are ARM, PowerPC and S/390.
1555 Erases all the flash memory regions reported by the target. This is
1556 equivalent to the CLI command flash-erase.
1558 -file-list-shared-libraries
1559 List the shared libraries in the program. This is
1560 equivalent to the CLI command "info shared".
1563 Catchpoints stopping the program when Ada exceptions are
1564 handled. This is equivalent to the CLI command "catch handlers".
1566 *** Changes in GDB 7.12
1568 * GDB and GDBserver now build with a C++ compiler by default.
1570 The --enable-build-with-cxx configure option is now enabled by
1571 default. One must now explicitly configure with
1572 --disable-build-with-cxx in order to build with a C compiler. This
1573 option will be removed in a future release.
1575 * GDBserver now supports recording btrace without maintaining an active
1578 * GDB now supports a negative repeat count in the 'x' command to examine
1579 memory backward from the given address. For example:
1582 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
1583 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
1584 (gdb) x/-5i 0x0000000000400580
1585 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
1586 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
1587 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
1588 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
1589 0x40057b <main(int, char**)+25>:
1590 callq 0x400536 <Func1(int, char const*)>
1592 * Fortran: Support structures with fields of dynamic types and
1593 arrays of dynamic types.
1595 * The symbol dumping maintenance commands have new syntax.
1596 maint print symbols [-pc address] [--] [filename]
1597 maint print symbols [-objfile objfile] [-source source] [--] [filename]
1598 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
1599 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
1600 maint print msymbols [-objfile objfile] [--] [filename]
1602 * GDB now supports multibit bitfields and enums in target register
1605 * New Python-based convenience function $_as_string(val), which returns
1606 the textual representation of a value. This function is especially
1607 useful to obtain the text label of an enum value.
1609 * Intel MPX bound violation handling.
1611 Segmentation faults caused by a Intel MPX boundary violation
1612 now display the kind of violation (upper or lower), the memory
1613 address accessed and the memory bounds, along with the usual
1614 signal received and code location.
1618 Program received signal SIGSEGV, Segmentation fault
1619 Upper bound violation while accessing address 0x7fffffffc3b3
1620 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
1621 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
1623 * Rust language support.
1624 GDB now supports debugging programs written in the Rust programming
1625 language. See https://www.rust-lang.org/ for more information about
1628 * Support for running interpreters on specified input/output devices
1630 GDB now supports a new mechanism that allows frontends to provide
1631 fully featured GDB console views, as a better alternative to
1632 building such views on top of the "-interpreter-exec console"
1633 command. See the new "new-ui" command below. With that command,
1634 frontends can now start GDB in the traditional command-line mode
1635 running in an embedded terminal emulator widget, and create a
1636 separate MI interpreter running on a specified i/o device. In this
1637 way, GDB handles line editing, history, tab completion, etc. in the
1638 console all by itself, and the GUI uses the separate MI interpreter
1639 for its own control and synchronization, invisible to the command
1642 * The "catch syscall" command catches groups of related syscalls.
1644 The "catch syscall" command now supports catching a group of related
1645 syscalls using the 'group:' or 'g:' prefix.
1650 skip -gfile file-glob-pattern
1651 skip -function function
1652 skip -rfunction regular-expression
1653 A generalized form of the skip command, with new support for
1654 glob-style file names and regular expressions for function names.
1655 Additionally, a file spec and a function spec may now be combined.
1657 maint info line-table REGEXP
1658 Display the contents of GDB's internal line table data structure.
1661 Run any GDB unit tests that were compiled in.
1664 Start a new user interface instance running INTERP as interpreter,
1665 using the TTY file for input/output.
1669 ** gdb.Breakpoint objects have a new attribute "pending", which
1670 indicates whether the breakpoint is pending.
1671 ** Three new breakpoint-related events have been added:
1672 gdb.breakpoint_created, gdb.breakpoint_modified, and
1673 gdb.breakpoint_deleted.
1675 signal-event EVENTID
1676 Signal ("set") the given MS-Windows event object. This is used in
1677 conjunction with the Windows JIT debugging (AeDebug) support, where
1678 the OS suspends a crashing process until a debugger can attach to
1679 it. Resuming the crashing process, in order to debug it, is done by
1680 signalling an event.
1682 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
1683 was added in GDBserver, including JIT compiling fast tracepoint's
1684 conditional expression bytecode into native code.
1686 * Support for various remote target protocols and ROM monitors has
1689 target m32rsdi Remote M32R debugging over SDI
1690 target mips MIPS remote debugging protocol
1691 target pmon PMON ROM monitor
1692 target ddb NEC's DDB variant of PMON for Vr4300
1693 target rockhopper NEC RockHopper variant of PMON
1694 target lsi LSI variant of PMO
1696 * Support for tracepoints and fast tracepoints on powerpc-linux,
1697 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
1698 including JIT compiling fast tracepoint's conditional expression
1699 bytecode into native code.
1701 * MI async record =record-started now includes the method and format used for
1702 recording. For example:
1704 =record-started,thread-group="i1",method="btrace",format="bts"
1706 * MI async record =thread-selected now includes the frame field. For example:
1708 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
1712 Andes NDS32 nds32*-*-elf
1714 *** Changes in GDB 7.11
1716 * GDB now supports debugging kernel-based threads on FreeBSD.
1718 * Per-inferior thread numbers
1720 Thread numbers are now per inferior instead of global. If you're
1721 debugging multiple inferiors, GDB displays thread IDs using a
1722 qualified INF_NUM.THR_NUM form. For example:
1726 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
1727 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1728 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1729 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1731 As consequence, thread numbers as visible in the $_thread
1732 convenience variable and in Python's InferiorThread.num attribute
1733 are no longer unique between inferiors.
1735 GDB now maintains a second thread ID per thread, referred to as the
1736 global thread ID, which is the new equivalent of thread numbers in
1737 previous releases. See also $_gthread below.
1739 For backwards compatibility, MI's thread IDs always refer to global
1742 * Commands that accept thread IDs now accept the qualified
1743 INF_NUM.THR_NUM form as well. For example:
1746 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1749 * In commands that accept a list of thread IDs, you can now refer to
1750 all threads of an inferior using a star wildcard. GDB accepts
1751 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1752 refer to all threads of the current inferior. For example, "info
1755 * You can use "info threads -gid" to display the global thread ID of
1758 * The new convenience variable $_gthread holds the global number of
1761 * The new convenience variable $_inferior holds the number of the
1764 * GDB now displays the ID and name of the thread that hit a breakpoint
1765 or received a signal, if your program is multi-threaded. For
1768 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1769 Thread 1 "main" received signal SIGINT, Interrupt.
1771 * Record btrace now supports non-stop mode.
1773 * Support for tracepoints on aarch64-linux was added in GDBserver.
1775 * The 'record instruction-history' command now indicates speculative execution
1776 when using the Intel Processor Trace recording format.
1778 * GDB now allows users to specify explicit locations, bypassing
1779 the linespec parser. This feature is also available to GDB/MI
1782 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1783 GDB now is able to debug both AArch64 applications and ARM applications
1786 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1787 including JIT compiling fast tracepoint's conditional expression bytecode
1790 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1792 * "info threads", "info inferiors", "info display", "info checkpoints"
1793 and "maint info program-spaces" now list the corresponding items in
1794 ascending ID order, for consistency with all other "info" commands.
1796 * In Ada, the overloads selection menu has been enhanced to display the
1797 parameter types and the return types for the matching overloaded subprograms.
1801 maint set target-non-stop (on|off|auto)
1802 maint show target-non-stop
1803 Control whether GDB targets always operate in non-stop mode even if
1804 "set non-stop" is "off". The default is "auto", meaning non-stop
1805 mode is enabled if supported by the target.
1807 maint set bfd-sharing
1808 maint show bfd-sharing
1809 Control the reuse of bfd objects.
1812 show debug bfd-cache
1813 Control display of debugging info regarding bfd caching.
1817 Control display of debugging info regarding FreeBSD threads.
1819 set remote multiprocess-extensions-packet
1820 show remote multiprocess-extensions-packet
1821 Set/show the use of the remote protocol multiprocess extensions.
1823 set remote thread-events
1824 show remote thread-events
1825 Set/show the use of thread create/exit events.
1827 set ada print-signatures on|off
1828 show ada print-signatures"
1829 Control whether parameter types and return types are displayed in overloads
1830 selection menus. It is activated (@code{on}) by default.
1834 Controls the maximum size of memory, in bytes, that GDB will
1835 allocate for value contents. Prevents incorrect programs from
1836 causing GDB to allocate overly large buffers. Default is 64k.
1838 * The "disassemble" command accepts a new modifier: /s.
1839 It prints mixed source+disassembly like /m with two differences:
1840 - disassembled instructions are now printed in program order, and
1841 - and source for all relevant files is now printed.
1842 The "/m" option is now considered deprecated: its "source-centric"
1843 output hasn't proved useful in practice.
1845 * The "record instruction-history" command accepts a new modifier: /s.
1846 It behaves exactly like /m and prints mixed source+disassembly.
1848 * The "set scheduler-locking" command supports a new mode "replay".
1849 It behaves like "off" in record mode and like "on" in replay mode.
1851 * Support for various ROM monitors has been removed:
1853 target dbug dBUG ROM monitor for Motorola ColdFire
1854 target picobug Motorola picobug monitor
1855 target dink32 DINK32 ROM monitor for PowerPC
1856 target m32r Renesas M32R/D ROM monitor
1857 target mon2000 mon2000 ROM monitor
1858 target ppcbug PPCBUG ROM monitor for PowerPC
1860 * Support for reading/writing memory and extracting values on architectures
1861 whose memory is addressable in units of any integral multiple of 8 bits.
1864 Allows to break when an Ada exception is handled.
1866 * New remote packets
1869 Indicates that an exec system call was executed.
1871 exec-events feature in qSupported
1872 The qSupported packet allows GDB to request support for exec
1873 events using the new 'gdbfeature' exec-event, and the qSupported
1874 response can contain the corresponding 'stubfeature'. Set and
1875 show commands can be used to display whether these features are enabled.
1878 Equivalent to interrupting with the ^C character, but works in
1881 thread created stop reason (T05 create:...)
1882 Indicates that the thread was just created and is stopped at entry.
1884 thread exit stop reply (w exitcode;tid)
1885 Indicates that the thread has terminated.
1888 Enables/disables thread create and exit event reporting. For
1889 example, this is used in non-stop mode when GDB stops a set of
1890 threads and synchronously waits for the their corresponding stop
1891 replies. Without exit events, if one of the threads exits, GDB
1892 would hang forever not knowing that it should no longer expect a
1893 stop for that same thread.
1896 Indicates that there are no resumed threads left in the target (all
1897 threads are stopped). The remote stub reports support for this stop
1898 reply to GDB's qSupported query.
1901 Enables/disables catching syscalls from the inferior process.
1902 The remote stub reports support for this packet to GDB's qSupported query.
1904 syscall_entry stop reason
1905 Indicates that a syscall was just called.
1907 syscall_return stop reason
1908 Indicates that a syscall just returned.
1910 * Extended-remote exec events
1912 ** GDB now has support for exec events on extended-remote Linux targets.
1913 For such targets with Linux kernels 2.5.46 and later, this enables
1914 follow-exec-mode and exec catchpoints.
1916 set remote exec-event-feature-packet
1917 show remote exec-event-feature-packet
1918 Set/show the use of the remote exec event feature.
1920 * Thread names in remote protocol
1922 The reply to qXfer:threads:read may now include a name attribute for each
1925 * Target remote mode fork and exec events
1927 ** GDB now has support for fork and exec events on target remote mode
1928 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1929 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1930 fork and exec catchpoints.
1932 * Remote syscall events
1934 ** GDB now has support for catch syscall on remote Linux targets,
1935 currently enabled on x86/x86_64 architectures.
1937 set remote catch-syscall-packet
1938 show remote catch-syscall-packet
1939 Set/show the use of the remote catch syscall feature.
1943 ** The -var-set-format command now accepts the zero-hexadecimal
1944 format. It outputs data in hexadecimal format with zero-padding on the
1949 ** gdb.InferiorThread objects have a new attribute "global_num",
1950 which refers to the thread's global thread ID. The existing
1951 "num" attribute now refers to the thread's per-inferior number.
1952 See "Per-inferior thread numbers" above.
1953 ** gdb.InferiorThread objects have a new attribute "inferior", which
1954 is the Inferior object the thread belongs to.
1956 *** Changes in GDB 7.10
1958 * Support for process record-replay and reverse debugging on aarch64*-linux*
1959 targets has been added. GDB now supports recording of A64 instruction set
1960 including advance SIMD instructions.
1962 * Support for Sun's version of the "stabs" debug file format has been removed.
1964 * GDB now honors the content of the file /proc/PID/coredump_filter
1965 (PID is the process ID) on GNU/Linux systems. This file can be used
1966 to specify the types of memory mappings that will be included in a
1967 corefile. For more information, please refer to the manual page of
1968 "core(5)". GDB also has a new command: "set use-coredump-filter
1969 on|off". It allows to set whether GDB will read the content of the
1970 /proc/PID/coredump_filter file when generating a corefile.
1972 * The "info os" command on GNU/Linux can now display information on
1974 "info os cpus" Listing of all cpus/cores on the system
1976 * GDB has two new commands: "set serial parity odd|even|none" and
1977 "show serial parity". These allows to set or show parity for the
1980 * The "info source" command now displays the producer string if it was
1981 present in the debug info. This typically includes the compiler version
1982 and may include things like its command line arguments.
1984 * The "info dll", an alias of the "info sharedlibrary" command,
1985 is now available on all platforms.
1987 * Directory names supplied to the "set sysroot" commands may be
1988 prefixed with "target:" to tell GDB to access shared libraries from
1989 the target system, be it local or remote. This replaces the prefix
1990 "remote:". The default sysroot has been changed from "" to
1991 "target:". "remote:" is automatically converted to "target:" for
1992 backward compatibility.
1994 * The system root specified by "set sysroot" will be prepended to the
1995 filename of the main executable (if reported to GDB as absolute by
1996 the operating system) when starting processes remotely, and when
1997 attaching to already-running local or remote processes.
1999 * GDB now supports automatic location and retrieval of executable
2000 files from remote targets. Remote debugging can now be initiated
2001 using only a "target remote" or "target extended-remote" command
2002 (no "set sysroot" or "file" commands are required). See "New remote
2005 * The "dump" command now supports verilog hex format.
2007 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
2009 * On GNU/Linux, GDB and gdbserver are now able to access executable
2010 and shared library files without a "set sysroot" command when
2011 attaching to processes running in different mount namespaces from
2012 the debugger. This makes it possible to attach to processes in
2013 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
2014 See "New remote packets" below.
2016 * The "tui reg" command now provides completion for all of the
2017 available register groups, including target specific groups.
2019 * The HISTSIZE environment variable is no longer read when determining
2020 the size of GDB's command history. GDB now instead reads the dedicated
2021 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
2022 disables truncation of command history. Non-numeric values of GDBHISTSIZE
2027 ** Memory ports can now be unbuffered.
2031 ** gdb.Objfile objects have a new attribute "username",
2032 which is the name of the objfile as specified by the user,
2033 without, for example, resolving symlinks.
2034 ** You can now write frame unwinders in Python.
2035 ** gdb.Type objects have a new method "optimized_out",
2036 returning optimized out gdb.Value instance of this type.
2037 ** gdb.Value objects have new methods "reference_value" and
2038 "const_value" which return a reference to the value and a
2039 "const" version of the value respectively.
2043 maint print symbol-cache
2044 Print the contents of the symbol cache.
2046 maint print symbol-cache-statistics
2047 Print statistics of symbol cache usage.
2049 maint flush-symbol-cache
2050 Flush the contents of the symbol cache.
2054 Start branch trace recording using Branch Trace Store (BTS) format.
2057 Evaluate expression by using the compiler and print result.
2061 Explicit commands for enabling and disabling tui mode.
2064 set mpx bound on i386 and amd64
2065 Support for bound table investigation on Intel MPX enabled applications.
2069 Start branch trace recording using Intel Processor Trace format.
2072 Print information about branch tracing internals.
2074 maint btrace packet-history
2075 Print the raw branch tracing data.
2077 maint btrace clear-packet-history
2078 Discard the stored raw branch tracing data.
2081 Discard all branch tracing data. It will be fetched and processed
2082 anew by the next "record" command.
2087 Renamed from "set debug dwarf2-die".
2088 show debug dwarf-die
2089 Renamed from "show debug dwarf2-die".
2091 set debug dwarf-read
2092 Renamed from "set debug dwarf2-read".
2093 show debug dwarf-read
2094 Renamed from "show debug dwarf2-read".
2096 maint set dwarf always-disassemble
2097 Renamed from "maint set dwarf2 always-disassemble".
2098 maint show dwarf always-disassemble
2099 Renamed from "maint show dwarf2 always-disassemble".
2101 maint set dwarf max-cache-age
2102 Renamed from "maint set dwarf2 max-cache-age".
2103 maint show dwarf max-cache-age
2104 Renamed from "maint show dwarf2 max-cache-age".
2106 set debug dwarf-line
2107 show debug dwarf-line
2108 Control display of debugging info regarding DWARF line processing.
2111 show max-completions
2112 Set the maximum number of candidates to be considered during
2113 completion. The default value is 200. This limit allows GDB
2114 to avoid generating large completion lists, the computation of
2115 which can cause the debugger to become temporarily unresponsive.
2117 set history remove-duplicates
2118 show history remove-duplicates
2119 Control the removal of duplicate history entries.
2121 maint set symbol-cache-size
2122 maint show symbol-cache-size
2123 Control the size of the symbol cache.
2125 set|show record btrace bts buffer-size
2126 Set and show the size of the ring buffer used for branch tracing in
2128 The obtained size may differ from the requested size. Use "info
2129 record" to see the obtained buffer size.
2131 set debug linux-namespaces
2132 show debug linux-namespaces
2133 Control display of debugging info regarding Linux namespaces.
2135 set|show record btrace pt buffer-size
2136 Set and show the size of the ring buffer used for branch tracing in
2137 Intel Processor Trace format.
2138 The obtained size may differ from the requested size. Use "info
2139 record" to see the obtained buffer size.
2141 maint set|show btrace pt skip-pad
2142 Set and show whether PAD packets are skipped when computing the
2145 * The command 'thread apply all' can now support new option '-ascending'
2146 to call its specified command for all threads in ascending order.
2148 * Python/Guile scripting
2150 ** GDB now supports auto-loading of Python/Guile scripts contained in the
2151 special section named `.debug_gdb_scripts'.
2153 * New remote packets
2155 qXfer:btrace-conf:read
2156 Return the branch trace configuration for the current thread.
2158 Qbtrace-conf:bts:size
2159 Set the requested ring buffer size for branch tracing in BTS format.
2162 Enable Intel Processor Trace-based branch tracing for the current
2163 process. The remote stub reports support for this packet to GDB's
2166 Qbtrace-conf:pt:size
2167 Set the requested ring buffer size for branch tracing in Intel Processor
2171 Indicates a memory breakpoint instruction was executed, irrespective
2172 of whether it was GDB that planted the breakpoint or the breakpoint
2173 is hardcoded in the program. This is required for correct non-stop
2177 Indicates the target stopped for a hardware breakpoint. This is
2178 required for correct non-stop mode operation.
2181 Return information about files on the remote system.
2183 qXfer:exec-file:read
2184 Return the full absolute name of the file that was executed to
2185 create a process running on the remote system.
2188 Select the filesystem on which vFile: operations with filename
2189 arguments will operate. This is required for GDB to be able to
2190 access files on remote targets where the remote stub does not
2191 share a common filesystem with the inferior(s).
2194 Indicates that a fork system call was executed.
2197 Indicates that a vfork system call was executed.
2199 vforkdone stop reason
2200 Indicates that a vfork child of the specified process has executed
2201 an exec or exit, allowing the vfork parent to resume execution.
2203 fork-events and vfork-events features in qSupported
2204 The qSupported packet allows GDB to request support for fork and
2205 vfork events using new 'gdbfeatures' fork-events and vfork-events,
2206 and the qSupported response can contain the corresponding
2207 'stubfeatures'. Set and show commands can be used to display
2208 whether these features are enabled.
2210 * Extended-remote fork events
2212 ** GDB now has support for fork events on extended-remote Linux
2213 targets. For targets with Linux kernels 2.5.60 and later, this
2214 enables follow-fork-mode and detach-on-fork for both fork and
2215 vfork, as well as fork and vfork catchpoints.
2217 * The info record command now shows the recording format and the
2218 branch tracing configuration for the current thread when using
2219 the btrace record target.
2220 For the BTS format, it shows the ring buffer size.
2222 * GDB now has support for DTrace USDT (Userland Static Defined
2223 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
2225 * GDB now supports access to vector registers on S/390 GNU/Linux
2228 * Removed command line options
2230 -xdb HP-UX XDB compatibility mode.
2232 * Removed targets and native configurations
2234 HP/PA running HP-UX hppa*-*-hpux*
2235 Itanium running HP-UX ia64-*-hpux*
2237 * New configure options
2240 This configure option allows the user to build GDB with support for
2241 Intel Processor Trace (default: auto). This requires libipt.
2243 --with-libipt-prefix=PATH
2244 Specify the path to the version of libipt that GDB should use.
2245 $PATH/include should contain the intel-pt.h header and
2246 $PATH/lib should contain the libipt.so library.
2248 *** Changes in GDB 7.9.1
2252 ** Xmethods can now specify a result type.
2254 *** Changes in GDB 7.9
2256 * GDB now supports hardware watchpoints on x86 GNU Hurd.
2260 ** You can now access frame registers from Python scripts.
2261 ** New attribute 'producer' for gdb.Symtab objects.
2262 ** gdb.Objfile objects have a new attribute "progspace",
2263 which is the gdb.Progspace object of the containing program space.
2264 ** gdb.Objfile objects have a new attribute "owner".
2265 ** gdb.Objfile objects have a new attribute "build_id",
2266 which is the build ID generated when the file was built.
2267 ** gdb.Objfile objects have a new method "add_separate_debug_file".
2268 ** A new event "gdb.clear_objfiles" has been added, triggered when
2269 selecting a new file to debug.
2270 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
2271 ** New function gdb.lookup_objfile.
2273 New events which are triggered when GDB modifies the state of the
2276 ** gdb.events.inferior_call_pre: Function call is about to be made.
2277 ** gdb.events.inferior_call_post: Function call has just been made.
2278 ** gdb.events.memory_changed: A memory location has been altered.
2279 ** gdb.events.register_changed: A register has been altered.
2281 * New Python-based convenience functions:
2283 ** $_caller_is(name [, number_of_frames])
2284 ** $_caller_matches(regexp [, number_of_frames])
2285 ** $_any_caller_is(name [, number_of_frames])
2286 ** $_any_caller_matches(regexp [, number_of_frames])
2288 * GDB now supports the compilation and injection of source code into
2289 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
2290 to compile the source code to object code, and if successful, inject
2291 and execute that code within the current context of the inferior.
2292 Currently the C language is supported. The commands used to
2293 interface with this new feature are:
2295 compile code [-raw|-r] [--] [source code]
2296 compile file [-raw|-r] filename
2300 demangle [-l language] [--] name
2301 Demangle "name" in the specified language, or the current language
2302 if elided. This command is renamed from the "maint demangle" command.
2303 The latter is kept as a no-op to avoid "maint demangle" being interpreted
2304 as "maint demangler-warning".
2306 queue-signal signal-name-or-number
2307 Queue a signal to be delivered to the thread when it is resumed.
2309 add-auto-load-scripts-directory directory
2310 Add entries to the list of directories from which to load auto-loaded
2313 maint print user-registers
2314 List all currently available "user" registers.
2316 compile code [-r|-raw] [--] [source code]
2317 Compile, inject, and execute in the inferior the executable object
2318 code produced by compiling the provided source code.
2320 compile file [-r|-raw] filename
2321 Compile and inject into the inferior the executable object code
2322 produced by compiling the source code stored in the filename
2325 * On resume, GDB now always passes the signal the program had stopped
2326 for to the thread the signal was sent to, even if the user changed
2327 threads before resuming. Previously GDB would often (but not
2328 always) deliver the signal to the thread that happens to be current
2331 * Conversely, the "signal" command now consistently delivers the
2332 requested signal to the current thread. GDB now asks for
2333 confirmation if the program had stopped for a signal and the user
2334 switched threads meanwhile.
2336 * "breakpoint always-inserted" modes "off" and "auto" merged.
2338 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
2339 won't remove breakpoints from the target until all threads stop,
2340 even in non-stop mode. The "auto" mode has been removed, and "off"
2341 is now the default mode.
2345 set debug symbol-lookup
2346 show debug symbol-lookup
2347 Control display of debugging info regarding symbol lookup.
2351 ** The -list-thread-groups command outputs an exit-code field for
2352 inferiors that have exited.
2356 MIPS SDE mips*-sde*-elf*
2360 Support for these obsolete configurations has been removed.
2362 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
2363 SGI Irix-5.x mips-*-irix5*
2364 SGI Irix-6.x mips-*-irix6*
2365 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
2366 VAX running Ultrix vax-*-ultrix*
2368 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2369 and "assf"), have been removed. Use the "sharedlibrary" command, or
2370 its alias "share", instead.
2372 *** Changes in GDB 7.8
2374 * New command line options
2377 This is an alias for the --data-directory option.
2379 * GDB supports printing and modifying of variable length automatic arrays
2380 as specified in ISO C99.
2382 * The ARM simulator now supports instruction level tracing
2383 with or without disassembly.
2387 GDB now has support for scripting using Guile. Whether this is
2388 available is determined at configure time.
2389 Guile version 2.0 or greater is required.
2390 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
2392 * New commands (for set/show, see "New options" below)
2396 Invoke CODE by passing it to the Guile interpreter.
2400 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
2402 info auto-load guile-scripts [regexp]
2403 Print the list of automatically loaded Guile scripts.
2405 * The source command is now capable of sourcing Guile scripts.
2406 This feature is dependent on the debugger being built with Guile support.
2410 set print symbol-loading (off|brief|full)
2411 show print symbol-loading
2412 Control whether to print informational messages when loading symbol
2413 information for a file. The default is "full", but when debugging
2414 programs with large numbers of shared libraries the amount of output
2415 becomes less useful.
2417 set guile print-stack (none|message|full)
2418 show guile print-stack
2419 Show a stack trace when an error is encountered in a Guile script.
2421 set auto-load guile-scripts (on|off)
2422 show auto-load guile-scripts
2423 Control auto-loading of Guile script files.
2425 maint ada set ignore-descriptive-types (on|off)
2426 maint ada show ignore-descriptive-types
2427 Control whether the debugger should ignore descriptive types in Ada
2428 programs. The default is not to ignore the descriptive types. See
2429 the user manual for more details on descriptive types and the intended
2430 usage of this option.
2432 set auto-connect-native-target
2434 Control whether GDB is allowed to automatically connect to the
2435 native target for the run, attach, etc. commands when not connected
2436 to any target yet. See also "target native" below.
2438 set record btrace replay-memory-access (read-only|read-write)
2439 show record btrace replay-memory-access
2440 Control what memory accesses are allowed during replay.
2442 maint set target-async (on|off)
2443 maint show target-async
2444 This controls whether GDB targets operate in synchronous or
2445 asynchronous mode. Normally the default is asynchronous, if it is
2446 available; but this can be changed to more easily debug problems
2447 occurring only in synchronous mode.
2449 set mi-async (on|off)
2451 Control whether MI asynchronous mode is preferred. This supersedes
2452 "set target-async" of previous GDB versions.
2454 * "set target-async" is deprecated as a CLI option and is now an alias
2455 for "set mi-async" (only puts MI into async mode).
2457 * Background execution commands (e.g., "c&", "s&", etc.) are now
2458 possible ``out of the box'' if the target supports them. Previously
2459 the user would need to explicitly enable the possibility with the
2460 "set target-async on" command.
2462 * New features in the GDB remote stub, GDBserver
2464 ** New option --debug-format=option1[,option2,...] allows one to add
2465 additional text to each output. At present only timestamps
2466 are supported: --debug-format=timestamps.
2467 Timestamps can also be turned on with the
2468 "monitor set debug-format timestamps" command from GDB.
2470 * The 'record instruction-history' command now starts counting instructions
2471 at one. This also affects the instruction ranges reported by the
2472 'record function-call-history' command when given the /i modifier.
2474 * The command 'record function-call-history' supports a new modifier '/c' to
2475 indent the function names based on their call stack depth.
2476 The fields for the '/i' and '/l' modifier have been reordered.
2477 The source line range is now prefixed with 'at'.
2478 The instruction range is now prefixed with 'inst'.
2479 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
2480 "record instruction-history" and "list" commands.
2482 * The ranges given as arguments to the 'record function-call-history' and
2483 'record instruction-history' commands are now inclusive.
2485 * The btrace record target now supports the 'record goto' command.
2486 For locations inside the execution trace, the back trace is computed
2487 based on the information stored in the execution trace.
2489 * The btrace record target supports limited reverse execution and replay.
2490 The target does not record data and therefore does not allow reading
2491 memory or registers.
2493 * The "catch syscall" command now works on s390*-linux* targets.
2495 * The "compare-sections" command is no longer specific to target
2496 remote. It now works with all targets.
2498 * All native targets are now consistently called "native".
2499 Consequently, the "target child", "target GNU", "target djgpp",
2500 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
2501 commands have been replaced with "target native". The QNX/NTO port
2502 leaves the "procfs" target in place and adds a "native" target for
2503 consistency with other ports. The impact on users should be minimal
2504 as these commands previously either throwed an error, or were
2505 no-ops. The target's name is visible in the output of the following
2506 commands: "help target", "info target", "info files", "maint print
2509 * The "target native" command now connects to the native target. This
2510 can be used to launch native programs even when "set
2511 auto-connect-native-target" is set to off.
2513 * GDB now supports access to Intel MPX registers on GNU/Linux.
2515 * Support for Intel AVX-512 registers on GNU/Linux.
2516 Support displaying and modifying Intel AVX-512 registers
2517 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
2519 * New remote packets
2521 qXfer:btrace:read's annex
2522 The qXfer:btrace:read packet supports a new annex 'delta' to read
2523 branch trace incrementally.
2527 ** Valid Python operations on gdb.Value objects representing
2528 structs/classes invoke the corresponding overloaded operators if
2530 ** New `Xmethods' feature in the Python API. Xmethods are
2531 additional methods or replacements for existing methods of a C++
2532 class. This feature is useful for those cases where a method
2533 defined in C++ source code could be inlined or optimized out by
2534 the compiler, making it unavailable to GDB.
2537 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
2539 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2540 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
2541 its alias "share", instead.
2543 * The commands "set remotebaud" and "show remotebaud" are no longer
2544 supported. Use "set serial baud" and "show serial baud" (respectively)
2549 ** A new option "-gdb-set mi-async" replaces "-gdb-set
2550 target-async". The latter is left as a deprecated alias of the
2551 former for backward compatibility. If the target supports it,
2552 CLI background execution commands are now always possible by
2553 default, independently of whether the frontend stated a
2554 preference for asynchronous execution with "-gdb-set mi-async".
2555 Previously "-gdb-set target-async off" affected both MI execution
2556 commands and CLI execution commands.
2558 *** Changes in GDB 7.7
2560 * Improved support for process record-replay and reverse debugging on
2561 arm*-linux* targets. Support for thumb32 and syscall instruction
2562 recording has been added.
2564 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
2566 * GDB now supports Fission DWP file format version 2.
2567 http://gcc.gnu.org/wiki/DebugFission
2569 * New convenience function "$_isvoid", to check whether an expression
2570 is void. A void expression is an expression where the type of the
2571 result is "void". For example, some convenience variables may be
2572 "void" when evaluated (e.g., "$_exitcode" before the execution of
2573 the program being debugged; or an undefined convenience variable).
2574 Another example, when calling a function whose return type is
2577 * The "maintenance print objfiles" command now takes an optional regexp.
2579 * The "catch syscall" command now works on arm*-linux* targets.
2581 * GDB now consistently shows "<not saved>" when printing values of
2582 registers the debug info indicates have not been saved in the frame
2583 and there's nowhere to retrieve them from
2584 (callee-saved/call-clobbered registers):
2589 (gdb) info registers rax
2592 Before, the former would print "<optimized out>", and the latter
2593 "*value not available*".
2595 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
2600 ** Frame filters and frame decorators have been added.
2601 ** Temporary breakpoints are now supported.
2602 ** Line tables representation has been added.
2603 ** New attribute 'parent_type' for gdb.Field objects.
2604 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
2605 ** New attribute 'name' for gdb.Type objects.
2609 Nios II ELF nios2*-*-elf
2610 Nios II GNU/Linux nios2*-*-linux
2611 Texas Instruments MSP430 msp430*-*-elf
2613 * Removed native configurations
2615 Support for these a.out NetBSD and OpenBSD obsolete configurations has
2616 been removed. ELF variants of these configurations are kept supported.
2618 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
2619 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
2620 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
2621 i[34567]86-*-openbsd3.[0-3]
2622 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
2623 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
2624 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
2628 Like "catch throw", but catches a re-thrown exception.
2629 maint check-psymtabs
2630 Renamed from old "maint check-symtabs".
2632 Perform consistency checks on symtabs.
2633 maint expand-symtabs
2634 Expand symtabs matching an optional regexp.
2637 Display the details of GDB configure-time options.
2639 maint set|show per-command
2640 maint set|show per-command space
2641 maint set|show per-command time
2642 maint set|show per-command symtab
2643 Enable display of per-command gdb resource usage.
2645 remove-symbol-file FILENAME
2646 remove-symbol-file -a ADDRESS
2647 Remove a symbol file added via add-symbol-file. The file to remove
2648 can be identified by its filename or by an address that lies within
2649 the boundaries of this symbol file in memory.
2652 info exceptions REGEXP
2653 Display the list of Ada exceptions defined in the program being
2654 debugged. If provided, only the exceptions whose names match REGEXP
2659 set debug symfile off|on
2661 Control display of debugging info regarding reading symbol files and
2662 symbol tables within those files
2664 set print raw frame-arguments
2665 show print raw frame-arguments
2666 Set/show whether to print frame arguments in raw mode,
2667 disregarding any defined pretty-printers.
2669 set remote trace-status-packet
2670 show remote trace-status-packet
2671 Set/show the use of remote protocol qTStatus packet.
2675 Control display of debugging messages related to Nios II targets.
2679 Control whether target-assisted range stepping is enabled.
2681 set startup-with-shell
2682 show startup-with-shell
2683 Specifies whether Unix child processes are started via a shell or
2688 Use the target memory cache for accesses to the code segment. This
2689 improves performance of remote debugging (particularly disassembly).
2691 * You can now use a literal value 'unlimited' for options that
2692 interpret 0 or -1 as meaning "unlimited". E.g., "set
2693 trace-buffer-size unlimited" is now an alias for "set
2694 trace-buffer-size -1" and "set height unlimited" is now an alias for
2697 * The "set debug symtab-create" debugging option of GDB has been changed to
2698 accept a verbosity level. 0 means "off", 1 provides basic debugging
2699 output, and values of 2 or greater provides more verbose output.
2701 * New command-line options
2703 Display the details of GDB configure-time options.
2705 * The command 'tsave' can now support new option '-ctf' to save trace
2706 buffer in Common Trace Format.
2708 * Newly installed $prefix/bin/gcore acts as a shell interface for the
2711 * GDB now implements the C++ 'typeid' operator.
2713 * The new convenience variable $_exception holds the exception being
2714 thrown or caught at an exception-related catchpoint.
2716 * The exception-related catchpoints, like "catch throw", now accept a
2717 regular expression which can be used to filter exceptions by type.
2719 * The new convenience variable $_exitsignal is automatically set to
2720 the terminating signal number when the program being debugged dies
2721 due to an uncaught signal.
2725 ** All MI commands now accept an optional "--language" option.
2726 Support for this feature can be verified by using the "-list-features"
2727 command, which should contain "language-option".
2729 ** The new command -info-gdb-mi-command allows the user to determine
2730 whether a GDB/MI command is supported or not.
2732 ** The "^error" result record returned when trying to execute an undefined
2733 GDB/MI command now provides a variable named "code" whose content is the
2734 "undefined-command" error code. Support for this feature can be verified
2735 by using the "-list-features" command, which should contain
2736 "undefined-command-error-code".
2738 ** The -trace-save MI command can optionally save trace buffer in Common
2741 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2743 ** The command -data-list-register-values now accepts an optional
2744 "--skip-unavailable" option. When used, only the available registers
2747 ** The new command -trace-frame-collected dumps collected variables,
2748 computed expressions, tvars, memory and registers in a traceframe.
2750 ** The commands -stack-list-locals, -stack-list-arguments and
2751 -stack-list-variables now accept an option "--skip-unavailable".
2752 When used, only the available locals or arguments are displayed.
2754 ** The -exec-run command now accepts an optional "--start" option.
2755 When used, the command follows the same semantics as the "start"
2756 command, stopping the program's execution at the start of its
2757 main subprogram. Support for this feature can be verified using
2758 the "-list-features" command, which should contain
2759 "exec-run-start-option".
2761 ** The new commands -catch-assert and -catch-exceptions insert
2762 catchpoints stopping the program when Ada exceptions are raised.
2764 ** The new command -info-ada-exceptions provides the equivalent of
2765 the new "info exceptions" command.
2767 * New system-wide configuration scripts
2768 A GDB installation now provides scripts suitable for use as system-wide
2769 configuration scripts for the following systems:
2773 * GDB now supports target-assigned range stepping with remote targets.
2774 This improves the performance of stepping source lines by reducing
2775 the number of control packets from/to GDB. See "New remote packets"
2778 * GDB now understands the element 'tvar' in the XML traceframe info.
2779 It has the id of the collected trace state variables.
2781 * On S/390 targets that provide the transactional-execution feature,
2782 the program interruption transaction diagnostic block (TDB) is now
2783 represented as a number of additional "registers" in GDB.
2785 * New remote packets
2789 The vCont packet supports a new 'r' action, that tells the remote
2790 stub to step through an address range itself, without GDB
2791 involvemement at each single-step.
2793 qXfer:libraries-svr4:read's annex
2794 The previously unused annex of the qXfer:libraries-svr4:read packet
2795 is now used to support passing an argument list. The remote stub
2796 reports support for this argument list to GDB's qSupported query.
2797 The defined arguments are "start" and "prev", used to reduce work
2798 necessary for library list updating, resulting in significant
2801 * New features in the GDB remote stub, GDBserver
2803 ** GDBserver now supports target-assisted range stepping. Currently
2804 enabled on x86/x86_64 GNU/Linux targets.
2806 ** GDBserver now adds element 'tvar' in the XML in the reply to
2807 'qXfer:traceframe-info:read'. It has the id of the collected
2808 trace state variables.
2810 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2813 * New 'z' formatter for printing and examining memory, this displays the
2814 value as hexadecimal zero padded on the left to the size of the type.
2816 * GDB can now use Windows x64 unwinding data.
2818 * The "set remotebaud" command has been replaced by "set serial baud".
2819 Similarly, "show remotebaud" has been replaced by "show serial baud".
2820 The "set remotebaud" and "show remotebaud" commands are still available
2821 to provide backward compatibility with older versions of GDB.
2823 *** Changes in GDB 7.6
2825 * Target record has been renamed to record-full.
2826 Record/replay is now enabled with the "record full" command.
2827 This also affects settings that are associated with full record/replay
2828 that have been moved from "set/show record" to "set/show record full":
2830 set|show record full insn-number-max
2831 set|show record full stop-at-limit
2832 set|show record full memory-query
2834 * A new record target "record-btrace" has been added. The new target
2835 uses hardware support to record the control-flow of a process. It
2836 does not support replaying the execution, but it implements the
2837 below new commands for investigating the recorded execution log.
2838 This new recording method can be enabled using:
2842 The "record-btrace" target is only available on Intel Atom processors
2843 and requires a Linux kernel 2.6.32 or later.
2845 * Two new commands have been added for record/replay to give information
2846 about the recorded execution without having to replay the execution.
2847 The commands are only supported by "record btrace".
2849 record instruction-history prints the execution history at
2850 instruction granularity
2852 record function-call-history prints the execution history at
2853 function granularity
2855 * New native configurations
2857 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2858 FreeBSD/powerpc powerpc*-*-freebsd
2859 x86_64/Cygwin x86_64-*-cygwin*
2860 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2864 ARM AArch64 aarch64*-*-elf
2865 ARM AArch64 GNU/Linux aarch64*-*-linux
2866 Lynx 178 PowerPC powerpc-*-lynx*178
2867 x86_64/Cygwin x86_64-*-cygwin*
2868 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2870 * If the configured location of system.gdbinit file (as given by the
2871 --with-system-gdbinit option at configure time) is in the
2872 data-directory (as specified by --with-gdb-datadir at configure
2873 time) or in one of its subdirectories, then GDB will look for the
2874 system-wide init file in the directory specified by the
2875 --data-directory command-line option.
2877 * New command line options:
2879 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2880 other initialization files, unlike -nx which disables all of them.
2882 * Removed command line options
2884 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2887 * The 'ptype' and 'whatis' commands now accept an argument to control
2890 * 'info proc' now works on some core files.
2894 ** Vectors can be created with gdb.Type.vector.
2896 ** Python's atexit.register now works in GDB.
2898 ** Types can be pretty-printed via a Python API.
2900 ** Python 3 is now supported (in addition to Python 2.4 or later)
2902 ** New class gdb.Architecture exposes GDB's internal representation
2903 of architecture in the Python API.
2905 ** New method Frame.architecture returns the gdb.Architecture object
2906 corresponding to the frame's architecture.
2908 * New Python-based convenience functions:
2910 ** $_memeq(buf1, buf2, length)
2911 ** $_streq(str1, str2)
2913 ** $_regex(str, regex)
2915 * The 'cd' command now defaults to using '~' (the home directory) if not
2918 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2919 default for GCC since November 2000.
2921 * The command 'forward-search' can now be abbreviated as 'fo'.
2923 * The command 'info tracepoints' can now display 'installed on target'
2924 or 'not installed on target' for each non-pending location of tracepoint.
2926 * New configure options
2928 --enable-libmcheck/--disable-libmcheck
2929 By default, development versions are built with -lmcheck on hosts
2930 that support it, in order to help track memory corruption issues.
2931 Release versions, on the other hand, are built without -lmcheck
2932 by default. The --enable-libmcheck/--disable-libmcheck configure
2933 options allow the user to override that default.
2934 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2935 This configure option allows the user to build GDB with
2936 libbabeltrace using which GDB can read Common Trace Format data.
2938 * New commands (for set/show, see "New options" below)
2941 Catch signals. This is similar to "handle", but allows commands and
2942 conditions to be attached.
2945 List the BFDs known to GDB.
2947 python-interactive [command]
2949 Start a Python interactive prompt, or evaluate the optional command
2950 and print the result of expressions.
2953 "py" is a new alias for "python".
2955 enable type-printer [name]...
2956 disable type-printer [name]...
2957 Enable or disable type printers.
2961 ** For the Renesas Super-H architecture, the "regs" command has been removed
2962 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2967 set print type methods (on|off)
2968 show print type methods
2969 Control whether method declarations are displayed by "ptype".
2970 The default is to show them.
2972 set print type typedefs (on|off)
2973 show print type typedefs
2974 Control whether typedef definitions are displayed by "ptype".
2975 The default is to show them.
2977 set filename-display basename|relative|absolute
2978 show filename-display
2979 Control the way in which filenames is displayed.
2980 The default is "relative", which preserves previous behavior.
2982 set trace-buffer-size
2983 show trace-buffer-size
2984 Request target to change the size of trace buffer.
2986 set remote trace-buffer-size-packet auto|on|off
2987 show remote trace-buffer-size-packet
2988 Control the use of the remote protocol `QTBuffer:size' packet.
2992 Control display of debugging messages related to ARM AArch64.
2995 set debug coff-pe-read
2996 show debug coff-pe-read
2997 Control display of debugging messages related to reading of COFF/PE
3002 Control display of debugging messages related to Mach-O symbols
3005 set debug notification
3006 show debug notification
3007 Control display of debugging info for async remote notification.
3011 ** Command parameter changes are now notified using new async record
3012 "=cmd-param-changed".
3013 ** Trace frame changes caused by command "tfind" are now notified using
3014 new async record "=traceframe-changed".
3015 ** The creation, deletion and modification of trace state variables
3016 are now notified using new async records "=tsv-created",
3017 "=tsv-deleted" and "=tsv-modified".
3018 ** The start and stop of process record are now notified using new
3019 async record "=record-started" and "=record-stopped".
3020 ** Memory changes are now notified using new async record
3022 ** The data-disassemble command response will include a "fullname" field
3023 containing the absolute file name when source has been requested.
3024 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
3025 command, to allow pattern filling of memory areas.
3026 ** New commands "-catch-load"/"-catch-unload" added for intercepting
3027 library load/unload events.
3028 ** The response to breakpoint commands and breakpoint async records
3029 includes an "installed" field containing a boolean state about each
3030 non-pending tracepoint location is whether installed on target or not.
3031 ** Output of the "-trace-status" command includes a "trace-file" field
3032 containing the name of the trace file being examined. This field is
3033 optional, and only present when examining a trace file.
3034 ** The "fullname" field is now always present along with the "file" field,
3035 even if the file cannot be found by GDB.
3037 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
3038 You must have the LZMA library available when configuring GDB for this
3039 feature to be enabled. For more information, see:
3040 http://fedoraproject.org/wiki/Features/MiniDebugInfo
3042 * New remote packets
3045 Set the size of trace buffer. The remote stub reports support for this
3046 packet to gdb's qSupported query.
3049 Enable Branch Trace Store (BTS)-based branch tracing for the current
3050 thread. The remote stub reports support for this packet to gdb's
3054 Disable branch tracing for the current thread. The remote stub reports
3055 support for this packet to gdb's qSupported query.
3058 Read the traced branches for the current thread. The remote stub
3059 reports support for this packet to gdb's qSupported query.
3061 *** Changes in GDB 7.5
3063 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
3064 for more x32 ABI info.
3066 * GDB now supports access to MIPS DSP registers on Linux targets.
3068 * GDB now supports debugging microMIPS binaries.
3070 * The "info os" command on GNU/Linux can now display information on
3071 several new classes of objects managed by the operating system:
3072 "info os procgroups" lists process groups
3073 "info os files" lists file descriptors
3074 "info os sockets" lists internet-domain sockets
3075 "info os shm" lists shared-memory regions
3076 "info os semaphores" lists semaphores
3077 "info os msg" lists message queues
3078 "info os modules" lists loaded kernel modules
3080 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
3081 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
3082 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
3083 options and inspect the probe arguments using the new $_probe_arg family
3084 of convenience variables. You can obtain more information about SystemTap
3085 in <http://sourceware.org/systemtap/>.
3087 * GDB now supports reversible debugging on ARM, it allows you to
3088 debug basic ARM and THUMB instructions, and provides
3089 record/replay support.
3091 * The option "symbol-reloading" has been deleted as it is no longer used.
3095 ** GDB commands implemented in Python can now be put in command class
3098 ** The "maint set python print-stack on|off" is now deleted.
3100 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
3101 apply "flag enum"-style pretty-printing to any enum.
3103 ** gdb.lookup_symbol can now work when there is no current frame.
3105 ** gdb.Symbol now has a 'line' attribute, holding the line number in
3106 the source at which the symbol was defined.
3108 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
3109 method 'value'. The former indicates whether the symbol needs a
3110 frame in order to compute its value, and the latter computes the
3113 ** A new method 'referenced_value' on gdb.Value objects which can
3114 dereference pointer as well as C++ reference values.
3116 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
3117 which return the global and static blocks (as gdb.Block objects),
3118 of the underlying symbol table, respectively.
3120 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
3121 object associated with a PC value.
3123 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
3124 of the address range occupied by code for the current source line.
3126 * Go language support.
3127 GDB now supports debugging programs written in the Go programming
3130 * GDBserver now supports stdio connections.
3131 E.g. (gdb) target remote | ssh myhost gdbserver - hello
3133 * The binary "gdbtui" can no longer be built or installed.
3134 Use "gdb -tui" instead.
3136 * GDB will now print "flag" enums specially. A flag enum is one where
3137 all the enumerator values have no bits in common when pairwise
3138 "and"ed. When printing a value whose type is a flag enum, GDB will
3139 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
3140 (gdb) print (enum E) 3
3143 * The filename part of a linespec will now match trailing components
3144 of a source file name. For example, "break gcc/expr.c:1000" will
3145 now set a breakpoint in build/gcc/expr.c, but not
3146 build/libcpp/expr.c.
3148 * The "info proc" and "generate-core-file" commands will now also
3149 work on remote targets connected to GDBserver on Linux.
3151 * The command "info catch" has been removed. It has been disabled
3152 since December 2007.
3154 * The "catch exception" and "catch assert" commands now accept
3155 a condition at the end of the command, much like the "break"
3156 command does. For instance:
3158 (gdb) catch exception Constraint_Error if Barrier = True
3160 Previously, it was possible to add a condition to such catchpoints,
3161 but it had to be done as a second step, after the catchpoint had been
3162 created, using the "condition" command.
3164 * The "info static-tracepoint-marker" command will now also work on
3165 native Linux targets with in-process agent.
3167 * GDB can now set breakpoints on inlined functions.
3169 * The .gdb_index section has been updated to include symbols for
3170 inlined functions. GDB will ignore older .gdb_index sections by
3171 default, which could cause symbol files to be loaded more slowly
3172 until their .gdb_index sections can be recreated. The new command
3173 "set use-deprecated-index-sections on" will cause GDB to use any older
3174 .gdb_index sections it finds. This will restore performance, but the
3175 ability to set breakpoints on inlined functions will be lost in symbol
3176 files with older .gdb_index sections.
3178 The .gdb_index section has also been updated to record more information
3179 about each symbol. This speeds up the "info variables", "info functions"
3180 and "info types" commands when used with programs having the .gdb_index
3181 section, as well as speeding up debugging with shared libraries using
3182 the .gdb_index section.
3184 * Ada support for GDB/MI Variable Objects has been added.
3186 * GDB can now support 'breakpoint always-inserted mode' in 'record'
3191 ** New command -info-os is the MI equivalent of "info os".
3193 ** Output logs ("set logging" and related) now include MI output.
3197 ** "set use-deprecated-index-sections on|off"
3198 "show use-deprecated-index-sections on|off"
3199 Controls the use of deprecated .gdb_index sections.
3201 ** "catch load" and "catch unload" can be used to stop when a shared
3202 library is loaded or unloaded, respectively.
3204 ** "enable count" can be used to auto-disable a breakpoint after
3207 ** "info vtbl" can be used to show the virtual method tables for
3208 C++ and Java objects.
3210 ** "explore" and its sub commands "explore value" and "explore type"
3211 can be used to recursively explore values and types of
3212 expressions. These commands are available only if GDB is
3213 configured with '--with-python'.
3215 ** "info auto-load" shows status of all kinds of auto-loaded files,
3216 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
3217 sequences of commands files, "info auto-load python-scripts"
3218 shows status of auto-loading Python script files,
3219 "info auto-load local-gdbinit" shows status of loading init file
3220 (.gdbinit) from current directory and "info auto-load libthread-db" shows
3221 status of inferior specific thread debugging shared library loading.
3223 ** "info auto-load-scripts", "set auto-load-scripts on|off"
3224 and "show auto-load-scripts" commands have been deprecated, use their
3225 "info auto-load python-scripts", "set auto-load python-scripts on|off"
3226 and "show auto-load python-scripts" counterparts instead.
3228 ** "dprintf location,format,args..." creates a dynamic printf, which
3229 is basically a breakpoint that does a printf and immediately
3230 resumes your program's execution, so it is like a printf that you
3231 can insert dynamically at runtime instead of at compiletime.
3233 ** "set print symbol"
3235 Controls whether GDB attempts to display the symbol, if any,
3236 corresponding to addresses it prints. This defaults to "on", but
3237 you can set it to "off" to restore GDB's previous behavior.
3239 * Deprecated commands
3241 ** For the Renesas Super-H architecture, the "regs" command has been
3242 deprecated, and "info all-registers" should be used instead.
3246 Renesas RL78 rl78-*-elf
3247 HP OpenVMS ia64 ia64-hp-openvms*
3249 * GDBserver supports evaluation of breakpoint conditions. When
3250 support is advertised by GDBserver, GDB may be told to send the
3251 breakpoint conditions in bytecode form to GDBserver. GDBserver
3252 will only report the breakpoint trigger to GDB when its condition
3257 set mips compression
3258 show mips compression
3259 Select the compressed ISA encoding used in functions that have no symbol
3260 information available. The encoding can be set to either of:
3263 and is updated automatically from ELF file flags if available.
3265 set breakpoint condition-evaluation
3266 show breakpoint condition-evaluation
3267 Control whether breakpoint conditions are evaluated by GDB ("host") or by
3268 GDBserver ("target"). Default option "auto" chooses the most efficient
3270 This option can improve debugger efficiency depending on the speed of the
3274 Disable auto-loading globally.
3277 Show auto-loading setting of all kinds of auto-loaded files.
3279 set auto-load gdb-scripts on|off
3280 show auto-load gdb-scripts
3281 Control auto-loading of GDB canned sequences of commands files.
3283 set auto-load python-scripts on|off
3284 show auto-load python-scripts
3285 Control auto-loading of Python script files.
3287 set auto-load local-gdbinit on|off
3288 show auto-load local-gdbinit
3289 Control loading of init file (.gdbinit) from current directory.
3291 set auto-load libthread-db on|off
3292 show auto-load libthread-db
3293 Control auto-loading of inferior specific thread debugging shared library.
3295 set auto-load scripts-directory <dir1>[:<dir2>...]
3296 show auto-load scripts-directory
3297 Set a list of directories from which to load auto-loaded scripts.
3298 Automatically loaded Python scripts and GDB scripts are located in one
3299 of the directories listed by this option.
3300 The delimiter (':' above) may differ according to the host platform.
3302 set auto-load safe-path <dir1>[:<dir2>...]
3303 show auto-load safe-path
3304 Set a list of directories from which it is safe to auto-load files.
3305 The delimiter (':' above) may differ according to the host platform.
3307 set debug auto-load on|off
3308 show debug auto-load
3309 Control display of debugging info for auto-loading the files above.
3311 set dprintf-style gdb|call|agent
3313 Control the way in which a dynamic printf is performed; "gdb"
3314 requests a GDB printf command, while "call" causes dprintf to call a
3315 function in the inferior. "agent" requests that the target agent
3316 (such as GDBserver) do the printing.
3318 set dprintf-function <expr>
3319 show dprintf-function
3320 set dprintf-channel <expr>
3321 show dprintf-channel
3322 Set the function and optional first argument to the call when using
3323 the "call" style of dynamic printf.
3325 set disconnected-dprintf on|off
3326 show disconnected-dprintf
3327 Control whether agent-style dynamic printfs continue to be in effect
3328 after GDB disconnects.
3330 * New configure options
3332 --with-auto-load-dir
3333 Configure default value for the 'set auto-load scripts-directory'
3334 setting above. It defaults to '$debugdir:$datadir/auto-load',
3335 $debugdir representing global debugging info directories (available
3336 via 'show debug-file-directory') and $datadir representing GDB's data
3337 directory (available via 'show data-directory').
3339 --with-auto-load-safe-path
3340 Configure default value for the 'set auto-load safe-path' setting
3341 above. It defaults to the --with-auto-load-dir setting.
3343 --without-auto-load-safe-path
3344 Set 'set auto-load safe-path' to '/', effectively disabling this
3347 * New remote packets
3349 z0/z1 conditional breakpoints extension
3351 The z0/z1 breakpoint insertion packets have been extended to carry
3352 a list of conditional expressions over to the remote stub depending on the
3353 condition evaluation mode. The use of this extension can be controlled
3354 via the "set remote conditional-breakpoints-packet" command.
3358 Specify the signals which the remote stub may pass to the debugged
3359 program without GDB involvement.
3361 * New command line options
3363 --init-command=FILE, -ix Like --command, -x but execute it
3364 before loading inferior.
3365 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
3366 execute it before loading inferior.
3368 *** Changes in GDB 7.4
3370 * GDB now handles ambiguous linespecs more consistently; the existing
3371 FILE:LINE support has been expanded to other types of linespecs. A
3372 breakpoint will now be set on all matching locations in all
3373 inferiors, and locations will be added or removed according to
3376 * GDB now allows you to skip uninteresting functions and files when
3377 stepping with the "skip function" and "skip file" commands.
3379 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
3380 and "show remote hardware-watchpoint-length-limit". These allows to
3381 set or show the maximum length limit (in bytes) of a remote
3382 target hardware watchpoint.
3384 This allows e.g. to use "unlimited" hardware watchpoints with the
3385 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
3386 watchpoints are slower than real hardware watchpoints but are
3387 significantly faster than gdb software watchpoints.
3391 ** The register_pretty_printer function in module gdb.printing now takes
3392 an optional `replace' argument. If True, the new printer replaces any
3395 ** The "maint set python print-stack on|off" command has been
3396 deprecated and will be deleted in GDB 7.5.
3397 A new command: "set python print-stack none|full|message" has
3398 replaced it. Additionally, the default for "print-stack" is
3399 now "message", which just prints the error message without
3402 ** A prompt substitution hook (prompt_hook) is now available to the
3405 ** A new Python module, gdb.prompt has been added to the GDB Python
3406 modules library. This module provides functionality for
3407 escape sequences in prompts (used by set/show
3408 extended-prompt). These escape sequences are replaced by their
3409 corresponding value.
3411 ** Python commands and convenience-functions located in
3412 'data-directory'/python/gdb/command and
3413 'data-directory'/python/gdb/function are now automatically loaded
3416 ** Blocks now provide four new attributes. global_block and
3417 static_block will return the global and static blocks
3418 respectively. is_static and is_global are boolean attributes
3419 that indicate if the block is one of those two types.
3421 ** Symbols now provide the "type" attribute, the type of the symbol.
3423 ** The "gdb.breakpoint" function has been deprecated in favor of
3426 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
3427 of a function. This class is based on the "finish" command
3428 available in the CLI.
3430 ** Type objects for struct and union types now allow access to
3431 the fields using standard Python dictionary (mapping) methods.
3432 For example, "some_type['myfield']" now works, as does
3433 "some_type.items()".
3435 ** A new event "gdb.new_objfile" has been added, triggered by loading a
3438 ** A new function, "deep_items" has been added to the gdb.types
3439 module in the GDB Python modules library. This function returns
3440 an iterator over the fields of a struct or union type. Unlike
3441 the standard Python "iteritems" method, it will recursively traverse
3442 any anonymous fields.
3446 ** "*stopped" events can report several new "reason"s, such as
3449 ** Breakpoint changes are now notified using new async records, like
3450 "=breakpoint-modified".
3452 ** New command -ada-task-info.
3454 * libthread-db-search-path now supports two special values: $sdir and $pdir.
3455 $sdir specifies the default system locations of shared libraries.
3456 $pdir specifies the directory where the libpthread used by the application
3459 GDB no longer looks in $sdir and $pdir after it has searched the directories
3460 mentioned in libthread-db-search-path. If you want to search those
3461 directories, they must be specified in libthread-db-search-path.
3462 The default value of libthread-db-search-path on GNU/Linux and Solaris
3463 systems is now "$sdir:$pdir".
3465 $pdir is not supported by gdbserver, it is currently ignored.
3466 $sdir is supported by gdbserver.
3468 * New configure option --with-iconv-bin.
3469 When using the internationalization support like the one in the GNU C
3470 library, GDB will invoke the "iconv" program to get a list of supported
3471 character sets. If this program lives in a non-standard location, one can
3472 use this option to specify where to find it.
3474 * When natively debugging programs on PowerPC BookE processors running
3475 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
3476 watchpoints, which specify a mask in addition to an address to watch.
3477 The mask specifies that some bits of an address (the bits which are
3478 reset in the mask) should be ignored when matching the address accessed
3479 by the inferior against the watchpoint address. See the "PowerPC Embedded"
3480 section in the user manual for more details.
3482 * The new option --once causes GDBserver to stop listening for connections once
3483 the first connection is made. The listening port used by GDBserver will
3484 become available after that.
3486 * New commands "info macros" and "alias" have been added.
3488 * New function parameters suffix @entry specifies value of function parameter
3489 at the time the function got called. Entry values are available only since
3495 "!" is now an alias of the "shell" command.
3496 Note that no space is needed between "!" and SHELL COMMAND.
3500 watch EXPRESSION mask MASK_VALUE
3501 The watch command now supports the mask argument which allows creation
3502 of masked watchpoints, if the current architecture supports this feature.
3504 info auto-load-scripts [REGEXP]
3505 This command was formerly named "maintenance print section-scripts".
3506 It is now generally useful and is no longer a maintenance-only command.
3508 info macro [-all] [--] MACRO
3509 The info macro command has new options `-all' and `--'. The first for
3510 printing all definitions of a macro. The second for explicitly specifying
3511 the end of arguments and the beginning of the macro name in case the macro
3512 name starts with a hyphen.
3514 collect[/s] EXPRESSIONS
3515 The tracepoint collect command now takes an optional modifier "/s"
3516 that directs it to dereference pointer-to-character types and
3517 collect the bytes of memory up to a zero byte. The behavior is
3518 similar to what you see when you use the regular print command on a
3519 string. An optional integer following the "/s" sets a bound on the
3520 number of bytes that will be collected.
3523 The trace start command now interprets any supplied arguments as a
3524 note to be recorded with the trace run, with an effect similar to
3525 setting the variable trace-notes.
3528 The trace stop command now interprets any arguments as a note to be
3529 mentioned along with the tstatus report that the trace was stopped
3530 with a command. The effect is similar to setting the variable
3533 * Tracepoints can now be enabled and disabled at any time after a trace
3534 experiment has been started using the standard "enable" and "disable"
3535 commands. It is now possible to start a trace experiment with no enabled
3536 tracepoints; GDB will display a warning, but will allow the experiment to
3537 begin, assuming that tracepoints will be enabled as needed while the trace
3540 * Fast tracepoints on 32-bit x86-architectures can now be placed at
3541 locations with 4-byte instructions, when they were previously
3542 limited to locations with instructions of 5 bytes or longer.
3546 set debug dwarf2-read
3547 show debug dwarf2-read
3548 Turns on or off display of debugging messages related to reading
3549 DWARF debug info. The default is off.
3551 set debug symtab-create
3552 show debug symtab-create
3553 Turns on or off display of debugging messages related to symbol table
3554 creation. The default is off.
3557 show extended-prompt
3558 Set the GDB prompt, and allow escape sequences to be inserted to
3559 display miscellaneous information (see 'help set extended-prompt'
3560 for the list of sequences). This prompt (and any information
3561 accessed through the escape sequences) is updated every time the
3562 prompt is displayed.
3564 set print entry-values (both|compact|default|if-needed|no|only|preferred)
3565 show print entry-values
3566 Set printing of frame argument values at function entry. In some cases
3567 GDB can determine the value of function argument which was passed by the
3568 function caller, even if the value was modified inside the called function.
3570 set debug entry-values
3571 show debug entry-values
3572 Control display of debugging info for determining frame argument values at
3573 function entry and virtual tail call frames.
3575 set basenames-may-differ
3576 show basenames-may-differ
3577 Set whether a source file may have multiple base names.
3578 (A "base name" is the name of a file with the directory part removed.
3579 Example: The base name of "/home/user/hello.c" is "hello.c".)
3580 If set, GDB will canonicalize file names (e.g., expand symlinks)
3581 before comparing them. Canonicalization is an expensive operation,
3582 but it allows the same file be known by more than one base name.
3583 If not set (the default), all source files are assumed to have just
3584 one base name, and gdb will do file name comparisons more efficiently.
3590 Set a user name and notes for the current and any future trace runs.
3591 This is useful for long-running and/or disconnected traces, to
3592 inform others (or yourself) as to who is running the trace, supply
3593 contact information, or otherwise explain what is going on.
3595 set trace-stop-notes
3596 show trace-stop-notes
3597 Set a note attached to the trace run, that is displayed when the
3598 trace has been stopped by a tstop command. This is useful for
3599 instance as an explanation, if you are stopping a trace run that was
3600 started by someone else.
3602 * New remote packets
3606 Dynamically enable a tracepoint in a started trace experiment.
3610 Dynamically disable a tracepoint in a started trace experiment.
3614 Set the user and notes of the trace run.
3618 Query the current status of a tracepoint.
3622 Query the minimum length of instruction at which a fast tracepoint may
3625 * Dcache size (number of lines) and line-size are now runtime-configurable
3626 via "set dcache line" and "set dcache line-size" commands.
3630 Texas Instruments TMS320C6x tic6x-*-*
3634 Renesas RL78 rl78-*-elf
3636 *** Changes in GDB 7.3.1
3638 * The build failure for NetBSD and OpenBSD targets have now been fixed.
3640 *** Changes in GDB 7.3
3642 * GDB has a new command: "thread find [REGEXP]".
3643 It finds the thread id whose name, target id, or thread extra info
3644 matches the given regular expression.
3646 * The "catch syscall" command now works on mips*-linux* targets.
3648 * The -data-disassemble MI command now supports modes 2 and 3 for
3649 dumping the instruction opcodes.
3651 * New command line options
3653 -data-directory DIR Specify DIR as the "data-directory".
3654 This is mostly for testing purposes.
3656 * The "maint set python auto-load on|off" command has been renamed to
3657 "set auto-load-scripts on|off".
3659 * GDB has a new command: "set directories".
3660 It is like the "dir" command except that it replaces the
3661 source path list instead of augmenting it.
3663 * GDB now understands thread names.
3665 On GNU/Linux, "info threads" will display the thread name as set by
3666 prctl or pthread_setname_np.
3668 There is also a new command, "thread name", which can be used to
3669 assign a name internally for GDB to display.
3672 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
3673 has been integrated into GDB.
3677 ** The function gdb.Write now accepts an optional keyword 'stream'.
3678 This keyword, when provided, will direct the output to either
3679 stdout, stderr, or GDB's logging output.
3681 ** Parameters can now be be sub-classed in Python, and in particular
3682 you may implement the get_set_doc and get_show_doc functions.
3683 This improves how Parameter set/show documentation is processed
3684 and allows for more dynamic content.
3686 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
3687 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
3688 have an is_valid method.
3690 ** Breakpoints can now be sub-classed in Python, and in particular
3691 you may implement a 'stop' function that is executed each time
3692 the inferior reaches that breakpoint.
3694 ** New function gdb.lookup_global_symbol looks up a global symbol.
3696 ** GDB values in Python are now callable if the value represents a
3697 function. For example, if 'some_value' represents a function that
3698 takes two integer parameters and returns a value, you can call
3699 that function like so:
3701 result = some_value (10,20)
3703 ** Module gdb.types has been added.
3704 It contains a collection of utilities for working with gdb.Types objects:
3705 get_basic_type, has_field, make_enum_dict.
3707 ** Module gdb.printing has been added.
3708 It contains utilities for writing and registering pretty-printers.
3709 New classes: PrettyPrinter, SubPrettyPrinter,
3710 RegexpCollectionPrettyPrinter.
3711 New function: register_pretty_printer.
3713 ** New commands "info pretty-printers", "enable pretty-printer" and
3714 "disable pretty-printer" have been added.
3716 ** gdb.parameter("directories") is now available.
3718 ** New function gdb.newest_frame returns the newest frame in the
3721 ** The gdb.InferiorThread class has a new "name" attribute. This
3722 holds the thread's name.
3724 ** Python Support for Inferior events.
3725 Python scripts can add observers to be notified of events
3726 occurring in the process being debugged.
3727 The following events are currently supported:
3728 - gdb.events.cont Continue event.
3729 - gdb.events.exited Inferior exited event.
3730 - gdb.events.stop Signal received, and Breakpoint hit events.
3734 ** GDB now puts template parameters in scope when debugging in an
3735 instantiation. For example, if you have:
3737 template<int X> int func (void) { return X; }
3739 then if you step into func<5>, "print X" will show "5". This
3740 feature requires proper debuginfo support from the compiler; it
3741 was added to GCC 4.5.
3743 ** The motion commands "next", "finish", "until", and "advance" now
3744 work better when exceptions are thrown. In particular, GDB will
3745 no longer lose control of the inferior; instead, the GDB will
3746 stop the inferior at the point at which the exception is caught.
3747 This functionality requires a change in the exception handling
3748 code that was introduced in GCC 4.5.
3750 * GDB now follows GCC's rules on accessing volatile objects when
3751 reading or writing target state during expression evaluation.
3752 One notable difference to prior behavior is that "print x = 0"
3753 no longer generates a read of x; the value of the assignment is
3754 now always taken directly from the value being assigned.
3756 * GDB now has some support for using labels in the program's source in
3757 linespecs. For instance, you can use "advance label" to continue
3758 execution to a label.
3760 * GDB now has support for reading and writing a new .gdb_index
3761 section. This section holds a fast index of DWARF debugging
3762 information and can be used to greatly speed up GDB startup and
3763 operation. See the documentation for `save gdb-index' for details.
3765 * The "watch" command now accepts an optional "-location" argument.
3766 When used, this causes GDB to watch the memory referred to by the
3767 expression. Such a watchpoint is never deleted due to it going out
3770 * GDB now supports thread debugging of core dumps on GNU/Linux.
3772 GDB now activates thread debugging using the libthread_db library
3773 when debugging GNU/Linux core dumps, similarly to when debugging
3774 live processes. As a result, when debugging a core dump file, GDB
3775 is now able to display pthread_t ids of threads. For example, "info
3776 threads" shows the same output as when debugging the process when it
3777 was live. In earlier releases, you'd see something like this:
3780 * 1 LWP 6780 main () at main.c:10
3782 While now you see this:
3785 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3787 It is also now possible to inspect TLS variables when debugging core
3790 When debugging a core dump generated on a machine other than the one
3791 used to run GDB, you may need to point GDB at the correct
3792 libthread_db library with the "set libthread-db-search-path"
3793 command. See the user manual for more details on this command.
3795 * When natively debugging programs on PowerPC BookE processors running
3796 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3797 which stop execution of the inferior whenever it executes an instruction
3798 at any address within the specified range. See the "PowerPC Embedded"
3799 section in the user manual for more details.
3801 * New features in the GDB remote stub, GDBserver
3803 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3804 and i686 LynxOS (version 5.x).
3806 ** GDBserver is now supported on Blackfin Linux.
3808 * New native configurations
3810 ia64 HP-UX ia64-*-hpux*
3814 Analog Devices, Inc. Blackfin Processor bfin-*
3816 * Ada task switching is now supported on sparc-elf targets when
3817 debugging a program using the Ravenscar Profile. For more information,
3818 see the "Tasking Support when using the Ravenscar Profile" section
3819 in the GDB user manual.
3821 * Guile support was removed.
3823 * New features in the GNU simulator
3825 ** The --map-info flag lists all known core mappings.
3827 ** CFI flashes may be simulated via the "cfi" device.
3829 *** Changes in GDB 7.2
3831 * Shared library support for remote targets by default
3833 When GDB is configured for a generic, non-OS specific target, like
3834 for example, --target=arm-eabi or one of the many *-*-elf targets,
3835 GDB now queries remote stubs for loaded shared libraries using the
3836 `qXfer:libraries:read' packet. Previously, shared library support
3837 was always disabled for such configurations.
3841 ** Argument Dependent Lookup (ADL)
3843 In C++ ADL lookup directs function search to the namespaces of its
3844 arguments even if the namespace has not been imported.
3854 Here the compiler will search for `foo' in the namespace of 'b'
3855 and find A::foo. GDB now supports this. This construct is commonly
3856 used in the Standard Template Library for operators.
3858 ** Improved User Defined Operator Support
3860 In addition to member operators, GDB now supports lookup of operators
3861 defined in a namespace and imported with a `using' directive, operators
3862 defined in the global scope, operators imported implicitly from an
3863 anonymous namespace, and the ADL operators mentioned in the previous
3865 GDB now also supports proper overload resolution for all the previously
3866 mentioned flavors of operators.
3868 ** static const class members
3870 Printing of static const class members that are initialized in the
3871 class definition has been fixed.
3873 * Windows Thread Information Block access.
3875 On Windows targets, GDB now supports displaying the Windows Thread
3876 Information Block (TIB) structure. This structure is visible either
3877 by using the new command `info w32 thread-information-block' or, by
3878 dereferencing the new convenience variable named `$_tlb', a
3879 thread-specific pointer to the TIB. This feature is also supported
3880 when remote debugging using GDBserver.
3882 * Static tracepoints
3884 Static tracepoints are calls in the user program into a tracing
3885 library. One such library is a port of the LTTng kernel tracer to
3886 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3887 When debugging with GDBserver, GDB now supports combining the GDB
3888 tracepoint machinery with such libraries. For example: the user can
3889 use GDB to probe a static tracepoint marker (a call from the user
3890 program into the tracing library) with the new "strace" command (see
3891 "New commands" below). This creates a "static tracepoint" in the
3892 breakpoint list, that can be manipulated with the same feature set
3893 as fast and regular tracepoints. E.g., collect registers, local and
3894 global variables, collect trace state variables, and define
3895 tracepoint conditions. In addition, the user can collect extra
3896 static tracepoint marker specific data, by collecting the new
3897 $_sdata internal variable. When analyzing the trace buffer, you can
3898 inspect $_sdata like any other variable available to GDB. For more
3899 information, see the "Tracepoints" chapter in GDB user manual. New
3900 remote packets have been defined to support static tracepoints, see
3901 the "New remote packets" section below.
3903 * Better reconstruction of tracepoints after disconnected tracing
3905 GDB will attempt to download the original source form of tracepoint
3906 definitions when starting a trace run, and then will upload these
3907 upon reconnection to the target, resulting in a more accurate
3908 reconstruction of the tracepoints that are in use on the target.
3912 You can now exercise direct control over the ways that GDB can
3913 affect your program. For instance, you can disallow the setting of
3914 breakpoints, so that the program can run continuously (assuming
3915 non-stop mode). In addition, the "observer" variable is available
3916 to switch all of the different controls; in observer mode, GDB
3917 cannot affect the target's behavior at all, which is useful for
3918 tasks like diagnosing live systems in the field.
3920 * The new convenience variable $_thread holds the number of the
3923 * New remote packets
3927 Return the address of the Windows Thread Information Block of a given thread.
3931 In response to several of the tracepoint packets, the target may now
3932 also respond with a number of intermediate `qRelocInsn' request
3933 packets before the final result packet, to have GDB handle
3934 relocating an instruction to execute at a different address. This
3935 is particularly useful for stubs that support fast tracepoints. GDB
3936 reports support for this feature in the qSupported packet.
3940 List static tracepoint markers in the target program.
3944 List static tracepoint markers at a given address in the target
3947 qXfer:statictrace:read
3949 Read the static trace data collected (by a `collect $_sdata'
3950 tracepoint action). The remote stub reports support for this packet
3951 to gdb's qSupported query.
3955 Send the current settings of GDB's permission flags.
3959 Send part of the source (textual) form of a tracepoint definition,
3960 which includes location, conditional, and action list.
3962 * The source command now accepts a -s option to force searching for the
3963 script in the source search path even if the script name specifies
3966 * New features in the GDB remote stub, GDBserver
3968 - GDBserver now support tracepoints (including fast tracepoints, and
3969 static tracepoints). The feature is currently supported by the
3970 i386-linux and amd64-linux builds. See the "Tracepoints support
3971 in gdbserver" section in the manual for more information.
3973 GDBserver JIT compiles the tracepoint's conditional agent
3974 expression bytecode into native code whenever possible for low
3975 overhead dynamic tracepoints conditionals. For such tracepoints,
3976 an expression that examines program state is evaluated when the
3977 tracepoint is reached, in order to determine whether to capture
3978 trace data. If the condition is simple and false, processing the
3979 tracepoint finishes very quickly and no data is gathered.
3981 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3982 for static tracepoints support.
3984 - GDBserver now supports x86_64 Windows 64-bit debugging.
3986 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3987 it understands register description.
3989 * The --batch flag now disables pagination and queries.
3991 * X86 general purpose registers
3993 GDB now supports reading/writing byte, word and double-word x86
3994 general purpose registers directly. This means you can use, say,
3995 $ah or $ax to refer, respectively, to the byte register AH and
3996 16-bit word register AX that are actually portions of the 32-bit
3997 register EAX or 64-bit register RAX.
3999 * The `commands' command now accepts a range of breakpoints to modify.
4000 A plain `commands' following a command that creates multiple
4001 breakpoints affects all the breakpoints set by that command. This
4002 applies to breakpoints set by `rbreak', and also applies when a
4003 single `break' command creates multiple breakpoints (e.g.,
4004 breakpoints on overloaded c++ functions).
4006 * The `rbreak' command now accepts a filename specification as part of
4007 its argument, limiting the functions selected by the regex to those
4008 in the specified file.
4010 * Support for remote debugging Windows and SymbianOS shared libraries
4011 from Unix hosts has been improved. Non Windows GDB builds now can
4012 understand target reported file names that follow MS-DOS based file
4013 system semantics, such as file names that include drive letters and
4014 use the backslash character as directory separator. This makes it
4015 possible to transparently use the "set sysroot" and "set
4016 solib-search-path" on Unix hosts to point as host copies of the
4017 target's shared libraries. See the new command "set
4018 target-file-system-kind" described below, and the "Commands to
4019 specify files" section in the user manual for more information.
4023 eval template, expressions...
4024 Convert the values of one or more expressions under the control
4025 of the string template to a command line, and call it.
4027 set target-file-system-kind unix|dos-based|auto
4028 show target-file-system-kind
4029 Set or show the assumed file system kind for target reported file
4032 save breakpoints <filename>
4033 Save all current breakpoint definitions to a file suitable for use
4034 in a later debugging session. To read the saved breakpoint
4035 definitions, use the `source' command.
4037 `save tracepoints' is a new alias for `save-tracepoints'. The latter
4040 info static-tracepoint-markers
4041 Display information about static tracepoint markers in the target.
4043 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
4044 Define a static tracepoint by probing a marker at the given
4045 function, line, address, or marker ID.
4049 Enable and disable observer mode.
4051 set may-write-registers on|off
4052 set may-write-memory on|off
4053 set may-insert-breakpoints on|off
4054 set may-insert-tracepoints on|off
4055 set may-insert-fast-tracepoints on|off
4056 set may-interrupt on|off
4057 Set individual permissions for GDB effects on the target. Note that
4058 some of these settings can have undesirable or surprising
4059 consequences, particularly when changed in the middle of a session.
4060 For instance, disabling the writing of memory can prevent
4061 breakpoints from being inserted, cause single-stepping to fail, or
4062 even crash your program, if you disable after breakpoints have been
4063 inserted. However, GDB should not crash.
4065 set record memory-query on|off
4066 show record memory-query
4067 Control whether to stop the inferior if memory changes caused
4068 by an instruction cannot be recorded.
4073 The disassemble command now supports "start,+length" form of two arguments.
4077 ** GDB now provides a new directory location, called the python directory,
4078 where Python scripts written for GDB can be installed. The location
4079 of that directory is <data-directory>/python, where <data-directory>
4080 is the GDB data directory. For more details, see section `Scripting
4081 GDB using Python' in the manual.
4083 ** The GDB Python API now has access to breakpoints, symbols, symbol
4084 tables, program spaces, inferiors, threads and frame's code blocks.
4085 Additionally, GDB Parameters can now be created from the API, and
4086 manipulated via set/show in the CLI.
4088 ** New functions gdb.target_charset, gdb.target_wide_charset,
4089 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
4091 ** New exception gdb.GdbError.
4093 ** Pretty-printers are now also looked up in the current program space.
4095 ** Pretty-printers can now be individually enabled and disabled.
4097 ** GDB now looks for names of Python scripts to auto-load in a
4098 special section named `.debug_gdb_scripts', in addition to looking
4099 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
4101 * Tracepoint actions were unified with breakpoint commands. In particular,
4102 there are no longer differences in "info break" output for breakpoints and
4103 tracepoints and the "commands" command can be used for both tracepoints and
4104 regular breakpoints.
4108 ARM Symbian arm*-*-symbianelf*
4110 * D language support.
4111 GDB now supports debugging programs written in the D programming
4114 * GDB now supports the extended ptrace interface for PowerPC which is
4115 available since Linux kernel version 2.6.34. This automatically enables
4116 any hardware breakpoints and additional hardware watchpoints available in
4117 the processor. The old ptrace interface exposes just one hardware
4118 watchpoint and no hardware breakpoints.
4120 * GDB is now able to use the Data Value Compare (DVC) register available on
4121 embedded PowerPC processors to implement in hardware simple watchpoint
4122 conditions of the form:
4124 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
4126 This works in native GDB running on Linux kernels with the extended ptrace
4127 interface mentioned above.
4129 *** Changes in GDB 7.1
4133 ** Namespace Support
4135 GDB now supports importing of namespaces in C++. This enables the
4136 user to inspect variables from imported namespaces. Support for
4137 namepace aliasing has also been added. So, if a namespace is
4138 aliased in the current scope (e.g. namepace C=A; ) the user can
4139 print variables using the alias (e.g. (gdb) print C::x).
4143 All known bugs relating to the printing of virtual base class were
4144 fixed. It is now possible to call overloaded static methods using a
4149 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
4150 and reinterpret_cast<> are now handled by the C++ expression parser.
4154 Xilinx MicroBlaze microblaze-*-*
4159 Xilinx MicroBlaze microblaze
4162 * Multi-program debugging.
4164 GDB now has support for multi-program (a.k.a. multi-executable or
4165 multi-exec) debugging. This allows for debugging multiple inferiors
4166 simultaneously each running a different program under the same GDB
4167 session. See "Debugging Multiple Inferiors and Programs" in the
4168 manual for more information. This implied some user visible changes
4169 in the multi-inferior support. For example, "info inferiors" now
4170 lists inferiors that are not running yet or that have exited
4171 already. See also "New commands" and "New options" below.
4173 * New tracing features
4175 GDB's tracepoint facility now includes several new features:
4177 ** Trace state variables
4179 GDB tracepoints now include support for trace state variables, which
4180 are variables managed by the target agent during a tracing
4181 experiment. They are useful for tracepoints that trigger each
4182 other, so for instance one tracepoint can count hits in a variable,
4183 and then a second tracepoint has a condition that is true when the
4184 count reaches a particular value. Trace state variables share the
4185 $-syntax of GDB convenience variables, and can appear in both
4186 tracepoint actions and condition expressions. Use the "tvariable"
4187 command to create, and "info tvariables" to view; see "Trace State
4188 Variables" in the manual for more detail.
4192 GDB now includes an option for defining fast tracepoints, which
4193 targets may implement more efficiently, such as by installing a jump
4194 into the target agent rather than a trap instruction. The resulting
4195 speedup can be by two orders of magnitude or more, although the
4196 tradeoff is that some program locations on some target architectures
4197 might not allow fast tracepoint installation, for instance if the
4198 instruction to be replaced is shorter than the jump. To request a
4199 fast tracepoint, use the "ftrace" command, with syntax identical to
4200 the regular trace command.
4202 ** Disconnected tracing
4204 It is now possible to detach GDB from the target while it is running
4205 a trace experiment, then reconnect later to see how the experiment
4206 is going. In addition, a new variable disconnected-tracing lets you
4207 tell the target agent whether to continue running a trace if the
4208 connection is lost unexpectedly.
4212 GDB now has the ability to save the trace buffer into a file, and
4213 then use that file as a target, similarly to you can do with
4214 corefiles. You can select trace frames, print data that was
4215 collected in them, and use tstatus to display the state of the
4216 tracing run at the moment that it was saved. To create a trace
4217 file, use "tsave <filename>", and to use it, do "target tfile
4220 ** Circular trace buffer
4222 You can ask the target agent to handle the trace buffer as a
4223 circular buffer, discarding the oldest trace frames to make room for
4224 newer ones, by setting circular-trace-buffer to on. This feature may
4225 not be available for all target agents.
4230 The disassemble command, when invoked with two arguments, now requires
4231 the arguments to be comma-separated.
4234 The info variables command now displays variable definitions. Files
4235 which only declare a variable are not shown.
4238 The source command is now capable of sourcing Python scripts.
4239 This feature is dependent on the debugger being build with Python
4242 Related to this enhancement is also the introduction of a new command
4243 "set script-extension" (see below).
4245 * New commands (for set/show, see "New options" below)
4247 record save [<FILENAME>]
4248 Save a file (in core file format) containing the process record
4249 execution log for replay debugging at a later time.
4251 record restore <FILENAME>
4252 Restore the process record execution log that was saved at an
4253 earlier time, for replay debugging.
4255 add-inferior [-copies <N>] [-exec <FILENAME>]
4258 clone-inferior [-copies <N>] [ID]
4259 Make a new inferior ready to execute the same program another
4260 inferior has loaded.
4265 maint info program-spaces
4266 List the program spaces loaded into GDB.
4268 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
4269 show remote interrupt-sequence
4270 Allow the user to select one of ^C, a BREAK signal or BREAK-g
4271 as the sequence to the remote target in order to interrupt the execution.
4272 Ctrl-C is a default. Some system prefers BREAK which is high level of
4273 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
4274 Magic SysRq g. It is BREAK signal and character 'g'.
4276 set remote interrupt-on-connect [on | off]
4277 show remote interrupt-on-connect
4278 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
4279 remote target when gdb connects to it. This is needed when you debug
4282 set remotebreak [on | off]
4284 Deprecated. Use "set/show remote interrupt-sequence" instead.
4286 tvariable $NAME [ = EXP ]
4287 Create or modify a trace state variable.
4290 List trace state variables and their values.
4292 delete tvariable $NAME ...
4293 Delete one or more trace state variables.
4296 Evaluate the given expressions without collecting anything into the
4297 trace buffer. (Valid in tracepoint actions only.)
4299 ftrace FN / FILE:LINE / *ADDR
4300 Define a fast tracepoint at the given function, line, or address.
4302 * New expression syntax
4304 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
4305 GDB now parses 0b101010 identically with 42.
4309 set follow-exec-mode new|same
4310 show follow-exec-mode
4311 Control whether GDB reuses the same inferior across an exec call or
4312 creates a new one. This is useful to be able to restart the old
4313 executable after the inferior having done an exec call.
4315 set default-collect EXPR, ...
4316 show default-collect
4317 Define a list of expressions to be collected at each tracepoint.
4318 This is a useful way to ensure essential items are not overlooked,
4319 such as registers or a critical global variable.
4321 set disconnected-tracing
4322 show disconnected-tracing
4323 If set to 1, the target is instructed to continue tracing if it
4324 loses its connection to GDB. If 0, the target is to stop tracing
4327 set circular-trace-buffer
4328 show circular-trace-buffer
4329 If set to on, the target is instructed to use a circular trace buffer
4330 and discard the oldest trace frames instead of stopping the trace due
4331 to a full trace buffer. If set to off, the trace stops when the buffer
4332 fills up. Some targets may not support this.
4334 set script-extension off|soft|strict
4335 show script-extension
4336 If set to "off", the debugger does not perform any script language
4337 recognition, and all sourced files are assumed to be GDB scripts.
4338 If set to "soft" (the default), files are sourced according to
4339 filename extension, falling back to GDB scripts if the first
4341 If set to "strict", files are sourced according to filename extension.
4343 set ada trust-PAD-over-XVS on|off
4344 show ada trust-PAD-over-XVS
4345 If off, activate a workaround against a bug in the debugging information
4346 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
4347 the GCC sources for more information about the GNAT encoding and
4348 PAD types in particular). It is always safe to set this option to
4349 off, but this introduces a slight performance penalty. The default
4352 * Python API Improvements
4354 ** GDB provides the new class gdb.LazyString. This is useful in
4355 some pretty-printing cases. The new method gdb.Value.lazy_string
4356 provides a simple way to create objects of this type.
4358 ** The fields returned by gdb.Type.fields now have an
4359 `is_base_class' attribute.
4361 ** The new method gdb.Type.range returns the range of an array type.
4363 ** The new method gdb.parse_and_eval can be used to parse and
4364 evaluate an expression.
4366 * New remote packets
4369 Define a trace state variable.
4372 Get the current value of a trace state variable.
4375 Set desired tracing behavior upon disconnection.
4378 Set the trace buffer to be linear or circular.
4381 Get data about the tracepoints currently in use.
4385 Process record now works correctly with hardware watchpoints.
4387 Multiple bug fixes have been made to the mips-irix port, making it
4388 much more reliable. In particular:
4389 - Debugging threaded applications is now possible again. Previously,
4390 GDB would hang while starting the program, or while waiting for
4391 the program to stop at a breakpoint.
4392 - Attaching to a running process no longer hangs.
4393 - An error occurring while loading a core file has been fixed.
4394 - Changing the value of the PC register now works again. This fixes
4395 problems observed when using the "jump" command, or when calling
4396 a function from GDB, or even when assigning a new value to $pc.
4397 - With the "finish" and "return" commands, the return value for functions
4398 returning a small array is now correctly printed.
4399 - It is now possible to break on shared library code which gets executed
4400 during a shared library init phase (code executed while executing
4401 their .init section). Previously, the breakpoint would have no effect.
4402 - GDB is now able to backtrace through the signal handler for
4403 non-threaded programs.
4405 PIE (Position Independent Executable) programs debugging is now supported.
4406 This includes debugging execution of PIC (Position Independent Code) shared
4407 libraries although for that, it should be possible to run such libraries as an
4410 *** Changes in GDB 7.0
4412 * GDB now has an interface for JIT compilation. Applications that
4413 dynamically generate code can create symbol files in memory and register
4414 them with GDB. For users, the feature should work transparently, and
4415 for JIT developers, the interface is documented in the GDB manual in the
4416 "JIT Compilation Interface" chapter.
4418 * Tracepoints may now be conditional. The syntax is as for
4419 breakpoints; either an "if" clause appended to the "trace" command,
4420 or the "condition" command is available. GDB sends the condition to
4421 the target for evaluation using the same bytecode format as is used
4422 for tracepoint actions.
4424 * The disassemble command now supports: an optional /r modifier, print the
4425 raw instructions in hex as well as in symbolic form, and an optional /m
4426 modifier to print mixed source+assembly.
4428 * Process record and replay
4430 In a architecture environment that supports ``process record and
4431 replay'', ``process record and replay'' target can record a log of
4432 the process execution, and replay it with both forward and reverse
4435 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
4436 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
4437 set execution-direction {forward|reverse}, for targets that support
4440 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
4441 feature is available with a native GDB running on kernel version
4444 * GDB now has support for multi-byte and wide character sets on the
4445 target. Strings whose character type is wchar_t, char16_t, or
4446 char32_t are now correctly printed. GDB supports wide- and unicode-
4447 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
4448 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
4449 `printf'. This feature requires iconv to work properly; if your
4450 system does not have a working iconv, GDB can use GNU libiconv. See
4451 the installation instructions for more information.
4453 * GDB now supports automatic retrieval of shared library files from
4454 remote targets. To use this feature, specify a system root that begins
4455 with the `remote:' prefix, either via the `set sysroot' command or via
4456 the `--with-sysroot' configure-time option.
4458 * "info sharedlibrary" now takes an optional regex of libraries to show,
4459 and it now reports if a shared library has no debugging information.
4461 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
4462 now complete on file names.
4464 * When completing in expressions, gdb will attempt to limit
4465 completions to allowable structure or union fields, where appropriate.
4466 For instance, consider:
4468 # struct example { int f1; double f2; };
4469 # struct example variable;
4472 If the user types TAB at the end of this command line, the available
4473 completions will be "f1" and "f2".
4475 * Inlined functions are now supported. They show up in backtraces, and
4476 the "step", "next", and "finish" commands handle them automatically.
4478 * GDB now supports the token-splicing (##) and stringification (#)
4479 operators when expanding macros. It also supports variable-arity
4482 * GDB now supports inspecting extra signal information, exported by
4483 the new $_siginfo convenience variable. The feature is currently
4484 implemented on linux ARM, i386 and amd64.
4486 * GDB can now display the VFP floating point registers and NEON vector
4487 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
4488 can provide these registers (requires Linux 2.6.30 or later). Remote
4489 and simulator targets may also provide them.
4491 * New remote packets
4494 Search memory for a sequence of bytes.
4497 Turn off `+'/`-' protocol acknowledgments to permit more efficient
4498 operation over reliable transport links. Use of this packet is
4499 controlled by the `set remote noack-packet' command.
4502 Kill the process with the specified process ID. Use this in preference
4503 to `k' when multiprocess protocol extensions are supported.
4506 Obtains additional operating system information
4510 Read or write additional signal information.
4512 * Removed remote protocol undocumented extension
4514 An undocumented extension to the remote protocol's `S' stop reply
4515 packet that permitted the stub to pass a process id was removed.
4516 Remote servers should use the `T' stop reply packet instead.
4518 * GDB now supports multiple function calling conventions according to the
4519 DWARF-2 DW_AT_calling_convention function attribute.
4521 * The SH target utilizes the aforementioned change to distinguish between gcc
4522 and Renesas calling convention. It also adds the new CLI commands
4523 `set/show sh calling-convention'.
4525 * GDB can now read compressed debug sections, as produced by GNU gold
4526 with the --compress-debug-sections=zlib flag.
4528 * 64-bit core files are now supported on AIX.
4530 * Thread switching is now supported on Tru64.
4532 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
4533 which will be allocated using malloc later in program execution.
4535 * The qXfer:libraries:read remote protocol packet now allows passing a
4536 list of section offsets.
4538 * On GNU/Linux, GDB can now attach to stopped processes. Several race
4539 conditions handling signals delivered during attach or thread creation
4540 have also been fixed.
4542 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
4543 From the user's standpoint, all unqualified instances of True and False
4544 are treated as the standard definitions, regardless of context.
4546 * GDB now parses C++ symbol and type names more flexibly. For
4549 template<typename T> class C { };
4552 GDB will now correctly handle all of:
4554 ptype C<char const *>
4555 ptype C<char const*>
4556 ptype C<const char *>
4557 ptype C<const char*>
4559 * New features in the GDB remote stub, gdbserver
4561 - The "--wrapper" command-line argument tells gdbserver to use a
4562 wrapper program to launch programs for debugging.
4564 - On PowerPC and S/390 targets, it is now possible to use a single
4565 gdbserver executable to debug both 32-bit and 64-bit programs.
4566 (This requires gdbserver itself to be built as a 64-bit executable.)
4568 - gdbserver uses the new noack protocol mode for TCP connections to
4569 reduce communications latency, if also supported and enabled in GDB.
4571 - Support for the sparc64-linux-gnu target is now included in
4574 - The amd64-linux build of gdbserver now supports debugging both
4575 32-bit and 64-bit programs.
4577 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
4578 now support hardware watchpoints, and will use them automatically
4583 GDB now has support for scripting using Python. Whether this is
4584 available is determined at configure time.
4586 New GDB commands can now be written in Python.
4588 * Ada tasking support
4590 Ada tasks can now be inspected in GDB. The following commands have
4594 Print the list of Ada tasks.
4596 Print detailed information about task number N.
4598 Print the task number of the current task.
4600 Switch the context of debugging to task number N.
4602 * Support for user-defined prefixed commands. The "define" command can
4603 add new commands to existing prefixes, e.g. "target".
4605 * Multi-inferior, multi-process debugging.
4607 GDB now has generalized support for multi-inferior debugging. See
4608 "Debugging Multiple Inferiors" in the manual for more information.
4609 Although availability still depends on target support, the command
4610 set is more uniform now. The GNU/Linux specific multi-forks support
4611 has been migrated to this new framework. This implied some user
4612 visible changes; see "New commands" and also "Removed commands"
4615 * Target descriptions can now describe the target OS ABI. See the
4616 "Target Description Format" section in the user manual for more
4619 * Target descriptions can now describe "compatible" architectures
4620 to indicate that the target can execute applications for a different
4621 architecture in addition to those for the main target architecture.
4622 See the "Target Description Format" section in the user manual for
4625 * Multi-architecture debugging.
4627 GDB now includes general supports for debugging applications on
4628 hybrid systems that use more than one single processor architecture
4629 at the same time. Each such hybrid architecture still requires
4630 specific support to be added. The only hybrid architecture supported
4631 in this version of GDB is the Cell Broadband Engine.
4633 * GDB now supports integrated debugging of Cell/B.E. applications that
4634 use both the PPU and SPU architectures. To enable support for hybrid
4635 Cell/B.E. debugging, you need to configure GDB to support both the
4636 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
4637 --enable-targets configure option.
4639 * Non-stop mode debugging.
4641 For some targets, GDB now supports an optional mode of operation in
4642 which you can examine stopped threads while other threads continue
4643 to execute freely. This is referred to as non-stop mode, with the
4644 old mode referred to as all-stop mode. See the "Non-Stop Mode"
4645 section in the user manual for more information.
4647 To be able to support remote non-stop debugging, a remote stub needs
4648 to implement the non-stop mode remote protocol extensions, as
4649 described in the "Remote Non-Stop" section of the user manual. The
4650 GDB remote stub, gdbserver, has been adjusted to support these
4651 extensions on linux targets.
4653 * New commands (for set/show, see "New options" below)
4655 catch syscall [NAME(S) | NUMBER(S)]
4656 Catch system calls. Arguments, which should be names of system
4657 calls or their numbers, mean catch only those syscalls. Without
4658 arguments, every syscall will be caught. When the inferior issues
4659 any of the specified syscalls, GDB will stop and announce the system
4660 call, both when it is called and when its call returns. This
4661 feature is currently available with a native GDB running on the
4662 Linux Kernel, under the following architectures: x86, x86_64,
4663 PowerPC and PowerPC64.
4665 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
4667 Search memory for a sequence of bytes.
4669 maint set python print-stack
4670 maint show python print-stack
4671 Show a stack trace when an error is encountered in a Python script.
4674 Invoke CODE by passing it to the Python interpreter.
4679 These allow macros to be defined, undefined, and listed
4683 Show operating system information about processes.
4686 List the inferiors currently under GDB's control.
4689 Switch focus to inferior number NUM.
4692 Detach from inferior number NUM.
4695 Kill inferior number NUM.
4699 set spu stop-on-load
4700 show spu stop-on-load
4701 Control whether to stop for new SPE threads during Cell/B.E. debugging.
4703 set spu auto-flush-cache
4704 show spu auto-flush-cache
4705 Control whether to automatically flush the software-managed cache
4706 during Cell/B.E. debugging.
4708 set sh calling-convention
4709 show sh calling-convention
4710 Control the calling convention used when calling SH target functions.
4713 show debug timestamp
4714 Control display of timestamps with GDB debugging output.
4716 set disassemble-next-line
4717 show disassemble-next-line
4718 Control display of disassembled source lines or instructions when
4721 set remote noack-packet
4722 show remote noack-packet
4723 Set/show the use of remote protocol QStartNoAckMode packet. See above
4724 under "New remote packets."
4726 set remote query-attached-packet
4727 show remote query-attached-packet
4728 Control use of remote protocol `qAttached' (query-attached) packet.
4730 set remote read-siginfo-object
4731 show remote read-siginfo-object
4732 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4735 set remote write-siginfo-object
4736 show remote write-siginfo-object
4737 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4740 set remote reverse-continue
4741 show remote reverse-continue
4742 Control use of remote protocol 'bc' (reverse-continue) packet.
4744 set remote reverse-step
4745 show remote reverse-step
4746 Control use of remote protocol 'bs' (reverse-step) packet.
4748 set displaced-stepping
4749 show displaced-stepping
4750 Control displaced stepping mode. Displaced stepping is a way to
4751 single-step over breakpoints without removing them from the debuggee.
4752 Also known as "out-of-line single-stepping".
4755 show debug displaced
4756 Control display of debugging info for displaced stepping.
4758 maint set internal-error
4759 maint show internal-error
4760 Control what GDB does when an internal error is detected.
4762 maint set internal-warning
4763 maint show internal-warning
4764 Control what GDB does when an internal warning is detected.
4769 Use a wrapper program to launch programs for debugging.
4771 set multiple-symbols (all|ask|cancel)
4772 show multiple-symbols
4773 The value of this variable can be changed to adjust the debugger behavior
4774 when an expression or a breakpoint location contains an ambiguous symbol
4775 name (an overloaded function name, for instance).
4777 set breakpoint always-inserted
4778 show breakpoint always-inserted
4779 Keep breakpoints always inserted in the target, as opposed to inserting
4780 them when resuming the target, and removing them when the target stops.
4781 This option can improve debugger performance on slow remote targets.
4783 set arm fallback-mode (arm|thumb|auto)
4784 show arm fallback-mode
4785 set arm force-mode (arm|thumb|auto)
4787 These commands control how ARM GDB determines whether instructions
4788 are ARM or Thumb. The default for both settings is auto, which uses
4789 the current CPSR value for instructions without symbols; previous
4790 versions of GDB behaved as if "set arm fallback-mode arm".
4792 set disable-randomization
4793 show disable-randomization
4794 Standalone programs run with the virtual address space randomization enabled
4795 by default on some platforms. This option keeps the addresses stable across
4796 multiple debugging sessions.
4800 Control whether other threads are stopped or not when some thread hits
4805 Requests that asynchronous execution is enabled in the target, if available.
4806 In this case, it's possible to resume target in the background, and interact
4807 with GDB while the target is running. "show target-async" displays the
4808 current state of asynchronous execution of the target.
4810 set target-wide-charset
4811 show target-wide-charset
4812 The target-wide-charset is the name of the character set that GDB
4813 uses when printing characters whose type is wchar_t.
4815 set tcp auto-retry (on|off)
4817 set tcp connect-timeout
4818 show tcp connect-timeout
4819 These commands allow GDB to retry failed TCP connections to a remote stub
4820 with a specified timeout period; this is useful if the stub is launched
4821 in parallel with GDB but may not be ready to accept connections immediately.
4823 set libthread-db-search-path
4824 show libthread-db-search-path
4825 Control list of directories which GDB will search for appropriate
4828 set schedule-multiple (on|off)
4829 show schedule-multiple
4830 Allow GDB to resume all threads of all processes or only threads of
4831 the current process.
4835 Use more aggressive caching for accesses to the stack. This improves
4836 performance of remote debugging (particularly backtraces) without
4837 affecting correctness.
4839 set interactive-mode (on|off|auto)
4840 show interactive-mode
4841 Control whether GDB runs in interactive mode (on) or not (off).
4842 When in interactive mode, GDB waits for the user to answer all
4843 queries. Otherwise, GDB does not wait and assumes the default
4844 answer. When set to auto (the default), GDB determines which
4845 mode to use based on the stdin settings.
4850 For program forks, this is replaced by the new more generic `info
4851 inferiors' command. To list checkpoints, you can still use the
4852 `info checkpoints' command, which was an alias for the `info forks'
4856 Replaced by the new `inferior' command. To switch between
4857 checkpoints, you can still use the `restart' command, which was an
4858 alias for the `fork' command.
4861 This is removed, since some targets don't have a notion of
4862 processes. To switch between processes, you can still use the
4863 `inferior' command using GDB's own inferior number.
4866 For program forks, this is replaced by the new more generic `kill
4867 inferior' command. To delete a checkpoint, you can still use the
4868 `delete checkpoint' command, which was an alias for the `delete
4872 For program forks, this is replaced by the new more generic `detach
4873 inferior' command. To detach a checkpoint, you can still use the
4874 `detach checkpoint' command, which was an alias for the `detach
4877 * New native configurations
4879 x86/x86_64 Darwin i[34567]86-*-darwin*
4881 x86_64 MinGW x86_64-*-mingw*
4885 Lattice Mico32 lm32-*
4886 x86 DICOS i[34567]86-*-dicos*
4887 x86_64 DICOS x86_64-*-dicos*
4890 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4891 (mingw32ce) debugging.
4897 These commands were actually not implemented on any target.
4899 *** Changes in GDB 6.8
4901 * New native configurations
4903 NetBSD/hppa hppa*-*netbsd*
4904 Xtensa GNU/Linux xtensa*-*-linux*
4908 NetBSD/hppa hppa*-*-netbsd*
4909 Xtensa GNU/Linux xtensa*-*-linux*
4911 * Change in command line behavior -- corefiles vs. process ids.
4913 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4914 attaching to process NUMBER fails, GDB no longer attempts to open a
4915 core file named NUMBER. Attaching to a program using the -c option
4916 is no longer supported. Instead, use the '-p' or '--pid' options.
4918 * GDB can now be built as a native debugger for debugging Windows x86
4919 (mingw32) Portable Executable (PE) programs.
4921 * Pending breakpoints no longer change their number when their address
4924 * GDB now supports breakpoints with multiple locations,
4925 including breakpoints on C++ constructors, inside C++ templates,
4926 and in inlined functions.
4928 * GDB's ability to debug optimized code has been improved. GDB more
4929 accurately identifies function bodies and lexical blocks that occupy
4930 more than one contiguous range of addresses.
4932 * Target descriptions can now describe registers for PowerPC.
4934 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4935 registers on PowerPC targets.
4937 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4938 targets even when the libthread_db library is not available.
4940 * The GDB remote stub, gdbserver, now supports the new file transfer
4941 commands (remote put, remote get, and remote delete).
4943 * The GDB remote stub, gdbserver, now supports run and attach in
4944 extended-remote mode.
4946 * hppa*64*-*-hpux11* target broken
4947 The debugger is unable to start a program and fails with the following
4948 error: "Error trying to get information about dynamic linker".
4949 The gdb-6.7 release is also affected.
4951 * GDB now supports the --enable-targets= configure option to allow
4952 building a single GDB executable that supports multiple remote
4953 target architectures.
4955 * GDB now supports debugging C and C++ programs which use the
4956 Decimal Floating Point extension. In addition, the PowerPC target
4957 now has a set of pseudo-registers to inspect decimal float values
4958 stored in two consecutive float registers.
4960 * The -break-insert MI command can optionally create pending
4963 * Improved support for debugging Ada
4964 Many improvements to the Ada language support have been made. These
4966 - Better support for Ada2005 interface types
4967 - Improved handling of arrays and slices in general
4968 - Better support for Taft-amendment types
4969 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4971 - Improved command completion in Ada
4974 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4979 set print frame-arguments (all|scalars|none)
4980 show print frame-arguments
4981 The value of this variable can be changed to control which argument
4982 values should be printed by the debugger when displaying a frame.
4987 Transfer files to and from a remote target, and delete remote files.
4994 Transfer files to and from a remote target, and delete remote files.
4996 * New remote packets
5003 Open, close, read, write, and delete files on the remote system.
5006 Attach to an existing process on the remote system, in extended-remote
5010 Run a new process on the remote system, in extended-remote mode.
5012 *** Changes in GDB 6.7
5014 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
5015 bfd, libiberty and opcodes, as revealed by static analysis donated by
5016 Coverity, Inc. (http://scan.coverity.com).
5018 * When looking up multiply-defined global symbols, GDB will now prefer the
5019 symbol definition in the current shared library if it was built using the
5020 -Bsymbolic linker option.
5022 * When the Text User Interface (TUI) is not configured, GDB will now
5023 recognize the -tui command-line option and print a message that the TUI
5026 * The GDB remote stub, gdbserver, now has lower overhead for high
5027 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
5029 * GDB for MIPS targets now autodetects whether a remote target provides
5030 32-bit or 64-bit register values.
5032 * Support for C++ member pointers has been improved.
5034 * GDB now understands XML target descriptions, which specify the
5035 target's overall architecture. GDB can read a description from
5036 a local file or over the remote serial protocol.
5038 * Vectors of single-byte data use a new integer type which is not
5039 automatically displayed as character or string data.
5041 * The /s format now works with the print command. It displays
5042 arrays of single-byte integers and pointers to single-byte integers
5045 * Target descriptions can now describe target-specific registers,
5046 for architectures which have implemented the support (currently
5047 only ARM, M68K, and MIPS).
5049 * GDB and the GDB remote stub, gdbserver, now support the XScale
5052 * The GDB remote stub, gdbserver, has been updated to support
5053 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
5054 has been rewritten to use the standard GDB remote protocol.
5056 * GDB can now step into C++ functions which are called through thunks.
5058 * GDB for the Cell/B.E. SPU now supports overlay debugging.
5060 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
5061 layout. It also supports a TextSeg= and DataSeg= response when only
5062 segment base addresses (rather than offsets) are available.
5064 * The /i format now outputs any trailing branch delay slot instructions
5065 immediately following the last instruction within the count specified.
5067 * The GDB remote protocol "T" stop reply packet now supports a
5068 "library" response. Combined with the new "qXfer:libraries:read"
5069 packet, this response allows GDB to debug shared libraries on targets
5070 where the operating system manages the list of loaded libraries (e.g.
5071 Windows and SymbianOS).
5073 * The GDB remote stub, gdbserver, now supports dynamic link libraries
5074 (DLLs) on Windows and Windows CE targets.
5076 * GDB now supports a faster verification that a .debug file matches its binary
5077 according to its build-id signature, if the signature is present.
5083 Enable or disable hardware flow control (RTS/CTS) on the serial port
5084 when debugging using remote targets.
5086 set mem inaccessible-by-default
5087 show mem inaccessible-by-default
5088 If the target supplies a memory map, for instance via the remote
5089 protocol's "qXfer:memory-map:read" packet, setting this variable
5090 prevents GDB from accessing memory outside the memory map. This
5091 is useful for targets with memory mapped registers or which react
5092 badly to accesses of unmapped address space.
5094 set breakpoint auto-hw
5095 show breakpoint auto-hw
5096 If the target supplies a memory map, for instance via the remote
5097 protocol's "qXfer:memory-map:read" packet, setting this variable
5098 lets GDB use hardware breakpoints automatically for memory regions
5099 where it can not use software breakpoints. This covers both the
5100 "break" command and internal breakpoints used for other commands
5101 including "next" and "finish".
5104 catch exception unhandled
5105 Stop the program execution when Ada exceptions are raised.
5108 Stop the program execution when an Ada assertion failed.
5112 Set an alternate system root for target files. This is a more
5113 general version of "set solib-absolute-prefix", which is now
5114 an alias to "set sysroot".
5117 Provide extended SPU facility status information. This set of
5118 commands is available only when debugging the Cell/B.E. SPU
5121 * New native configurations
5123 OpenBSD/sh sh*-*openbsd*
5126 unset tdesc filename
5128 Use the specified local file as an XML target description, and do
5129 not query the target for its built-in description.
5133 OpenBSD/sh sh*-*-openbsd*
5134 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
5135 Toshiba Media Processor mep-elf
5137 * New remote packets
5140 Ignore the specified signals; pass them directly to the debugged program
5141 without stopping other threads or reporting them to GDB.
5143 qXfer:features:read:
5144 Read an XML target description from the target, which describes its
5149 Read or write contents of an spufs file on the target system. These
5150 packets are available only on the Cell/B.E. SPU architecture.
5152 qXfer:libraries:read:
5153 Report the loaded shared libraries. Combined with new "T" packet
5154 response, this packet allows GDB to debug shared libraries on
5155 targets where the operating system manages the list of loaded
5156 libraries (e.g. Windows and SymbianOS).
5160 Support for these obsolete configurations has been removed.
5168 i[34567]86-*-lynxos*
5169 i[34567]86-*-netware*
5170 i[34567]86-*-sco3.2v5*
5171 i[34567]86-*-sco3.2v4*
5173 i[34567]86-*-sysv4.2*
5176 i[34567]86-*-unixware2*
5177 i[34567]86-*-unixware*
5186 * Other removed features
5193 Various m68k-only ROM monitors.
5200 Various Renesas ROM monitors and debugging interfaces for SH and
5205 Support for a Macraigor serial interface to on-chip debugging.
5206 GDB does not directly support the newer parallel or USB
5211 A debug information format. The predecessor to DWARF 2 and
5212 DWARF 3, which are still supported.
5214 Support for the HP aCC compiler on HP-UX/PA-RISC
5216 SOM-encapsulated symbolic debugging information, automatic
5217 invocation of pxdb, and the aCC custom C++ ABI. This does not
5218 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
5219 with aCC can still be debugged on an assembly level.
5221 MIPS ".pdr" sections
5223 A MIPS-specific format used to describe stack frame layout
5224 in debugging information.
5228 GDB could work with an older version of Guile to debug
5229 the interpreter and Scheme programs running in it.
5231 set mips stack-arg-size
5232 set mips saved-gpreg-size
5234 Use "set mips abi" to control parameter passing for MIPS.
5236 *** Changes in GDB 6.6
5241 Cell Broadband Engine SPU spu-elf
5243 * GDB can now be configured as a cross-debugger targeting native Windows
5244 (mingw32) or Cygwin. It can communicate with a remote debugging stub
5245 running on a Windows system over TCP/IP to debug Windows programs.
5247 * The GDB remote stub, gdbserver, has been updated to support Windows and
5248 Cygwin debugging. Both single-threaded and multi-threaded programs are
5251 * The "set trust-readonly-sections" command works again. This command was
5252 broken in GDB 6.3, 6.4, and 6.5.
5254 * The "load" command now supports writing to flash memory, if the remote
5255 stub provides the required support.
5257 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
5258 longer requires symbolic debug information (e.g. DWARF-2).
5263 unset substitute-path
5264 show substitute-path
5265 Manage a list of substitution rules that GDB uses to rewrite the name
5266 of the directories where the sources are located. This can be useful
5267 for instance when the sources were moved to a different location
5268 between compilation and debugging.
5272 Print each CLI command as it is executed. Each command is prefixed with
5273 a number of `+' symbols representing the nesting depth.
5274 The source command now has a `-v' option to enable the same feature.
5278 The ARM Demon monitor support (RDP protocol, "target rdp").
5280 Kernel Object Display, an embedded debugging feature which only worked with
5281 an obsolete version of Cisco IOS.
5283 The 'set download-write-size' and 'show download-write-size' commands.
5285 * New remote packets
5288 Tell a stub about GDB client features, and request remote target features.
5289 The first feature implemented is PacketSize, which allows the target to
5290 specify the size of packets it can handle - to minimize the number of
5291 packets required and improve performance when connected to a remote
5295 Fetch an OS auxilliary vector from the remote stub. This packet is a
5296 more efficient replacement for qPart:auxv:read.
5298 qXfer:memory-map:read:
5299 Fetch a memory map from the remote stub, including information about
5300 RAM, ROM, and flash memory devices.
5305 Erase and program a flash memory device.
5307 * Removed remote packets
5310 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
5311 used it, and only gdbserver implemented it.
5313 *** Changes in GDB 6.5
5317 Renesas M32C/M16C m32c-elf
5319 Morpho Technologies ms1 ms1-elf
5323 init-if-undefined Initialize a convenience variable, but
5324 only if it doesn't already have a value.
5326 The following commands are presently only implemented for native GNU/Linux:
5328 checkpoint Save a snapshot of the program state.
5330 restart <n> Return the program state to a
5331 previously saved state.
5333 info checkpoints List currently saved checkpoints.
5335 delete-checkpoint <n> Delete a previously saved checkpoint.
5337 set|show detach-on-fork Tell gdb whether to detach from a newly
5338 forked process, or to keep debugging it.
5340 info forks List forks of the user program that
5341 are available to be debugged.
5343 fork <n> Switch to debugging one of several
5344 forks of the user program that are
5345 available to be debugged.
5347 delete-fork <n> Delete a fork from the list of forks
5348 that are available to be debugged (and
5349 kill the forked process).
5351 detach-fork <n> Delete a fork from the list of forks
5352 that are available to be debugged (and
5353 allow the process to continue).
5357 Morpho Technologies ms2 ms1-elf
5359 * Improved Windows host support
5361 GDB now builds as a cross debugger hosted on i686-mingw32, including
5362 native console support, and remote communications using either
5363 network sockets or serial ports.
5365 * Improved Modula-2 language support
5367 GDB can now print most types in the Modula-2 syntax. This includes:
5368 basic types, set types, record types, enumerated types, range types,
5369 pointer types and ARRAY types. Procedure var parameters are correctly
5370 printed and hexadecimal addresses and character constants are also
5371 written in the Modula-2 syntax. Best results can be obtained by using
5372 GNU Modula-2 together with the -gdwarf-2 command line option.
5376 The ARM rdi-share module.
5378 The Netware NLM debug server.
5380 *** Changes in GDB 6.4
5382 * New native configurations
5384 OpenBSD/arm arm*-*-openbsd*
5385 OpenBSD/mips64 mips64-*-openbsd*
5389 Morpho Technologies ms1 ms1-elf
5391 * New command line options
5393 --batch-silent As for --batch, but totally silent.
5394 --return-child-result The debugger will exist with the same value
5395 the child (debugged) program exited with.
5396 --eval-command COMMAND, -ex COMMAND
5397 Execute a single GDB CLI command. This may be
5398 specified multiple times and in conjunction
5399 with the --command (-x) option.
5401 * Deprecated commands removed
5403 The following commands, that were deprecated in 2000, have been
5407 set|show arm disassembly-flavor set|show arm disassembler
5408 othernames set arm disassembler
5409 set|show remotedebug set|show debug remote
5410 set|show archdebug set|show debug arch
5411 set|show eventdebug set|show debug event
5414 * New BSD user-level threads support
5416 It is now possible to debug programs using the user-level threads
5417 library on OpenBSD and FreeBSD. Currently supported (target)
5420 FreeBSD/amd64 x86_64-*-freebsd*
5421 FreeBSD/i386 i386-*-freebsd*
5422 OpenBSD/i386 i386-*-openbsd*
5424 Note that the new kernel threads libraries introduced in FreeBSD 5.x
5425 are not yet supported.
5427 * New support for Matsushita MN10300 w/sim added
5428 (Work in progress). mn10300-elf.
5430 * REMOVED configurations and files
5432 VxWorks and the XDR protocol *-*-vxworks
5433 Motorola MCORE mcore-*-*
5434 National Semiconductor NS32000 ns32k-*-*
5436 * New "set print array-indexes" command
5438 After turning this setting "on", GDB prints the index of each element
5439 when displaying arrays. The default is "off" to preserve the previous
5442 * VAX floating point support
5444 GDB now supports the not-quite-ieee VAX F and D floating point formats.
5446 * User-defined command support
5448 In addition to using $arg0..$arg9 for argument passing, it is now possible
5449 to use $argc to determine now many arguments have been passed. See the
5450 section on user-defined commands in the user manual for more information.
5452 *** Changes in GDB 6.3:
5454 * New command line option
5456 GDB now accepts -l followed by a number to set the timeout for remote
5459 * GDB works with GCC -feliminate-dwarf2-dups
5461 GDB now supports a more compact representation of DWARF-2 debug
5462 information using DW_FORM_ref_addr references. These are produced
5463 by GCC with the option -feliminate-dwarf2-dups and also by some
5464 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
5465 to use -feliminate-dwarf2-dups.
5467 * Internationalization
5469 When supported by the host system, GDB will be built with
5470 internationalization (libintl). The task of marking up the sources is
5471 continued, we're looking forward to our first translation.
5475 Initial support for debugging programs compiled with the GNAT
5476 implementation of the Ada programming language has been integrated
5477 into GDB. In this release, support is limited to expression evaluation.
5479 * New native configurations
5481 GNU/Linux/m32r m32r-*-linux-gnu
5485 GDB's remote protocol now includes support for the 'p' packet. This
5486 packet is used to fetch individual registers from a remote inferior.
5488 * END-OF-LIFE registers[] compatibility module
5490 GDB's internal register infrastructure has been completely rewritten.
5491 The new infrastructure making possible the implementation of key new
5492 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
5495 GDB 6.3 will be the last release to include the registers[]
5496 compatibility module that allowed out-of-date configurations to
5497 continue to work. This change directly impacts the following
5507 powerpc bdm protocol
5509 Unless there is activity to revive these configurations, they will be
5510 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
5512 * OBSOLETE configurations and files
5514 Configurations that have been declared obsolete in this release have
5515 been commented out. Unless there is activity to revive these
5516 configurations, the next release of GDB will have their sources
5517 permanently REMOVED.
5526 *** Changes in GDB 6.2.1:
5528 * MIPS `break main; run' gave an heuristic-fence-post warning
5530 When attempting to run even a simple program, a warning about
5531 heuristic-fence-post being hit would be reported. This problem has
5534 * MIPS IRIX 'long double' crashed GDB
5536 When examining a long double variable, GDB would get a segmentation
5537 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
5538 IRIX long double values).
5542 A bug in the VAX stack code was causing problems with the "next"
5543 command. This problem has been fixed.
5545 *** Changes in GDB 6.2:
5547 * Fix for ``many threads''
5549 On GNU/Linux systems that use the NPTL threads library, a program
5550 rapidly creating and deleting threads would confuse GDB leading to the
5553 ptrace: No such process.
5554 thread_db_get_info: cannot get thread info: generic error
5556 This problem has been fixed.
5558 * "-async" and "-noasync" options removed.
5560 Support for the broken "-noasync" option has been removed (it caused
5563 * New ``start'' command.
5565 This command runs the program until the beginning of the main procedure.
5567 * New BSD Kernel Data Access Library (libkvm) interface
5569 Using ``target kvm'' it is now possible to debug kernel core dumps and
5570 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
5571 platforms. Currently supported (native-only) configurations are:
5573 FreeBSD/amd64 x86_64-*-freebsd*
5574 FreeBSD/i386 i?86-*-freebsd*
5575 NetBSD/i386 i?86-*-netbsd*
5576 NetBSD/m68k m68*-*-netbsd*
5577 NetBSD/sparc sparc-*-netbsd*
5578 OpenBSD/amd64 x86_64-*-openbsd*
5579 OpenBSD/i386 i?86-*-openbsd*
5580 OpenBSD/m68k m68*-openbsd*
5581 OpenBSD/sparc sparc-*-openbsd*
5583 * Signal trampoline code overhauled
5585 Many generic problems with GDB's signal handling code have been fixed.
5586 These include: backtraces through non-contiguous stacks; recognition
5587 of sa_sigaction signal trampolines; backtrace from a NULL pointer
5588 call; backtrace through a signal trampoline; step into and out of
5589 signal handlers; and single-stepping in the signal trampoline.
5591 Please note that kernel bugs are a limiting factor here. These
5592 features have been shown to work on an s390 GNU/Linux system that
5593 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
5595 * Cygwin support for DWARF 2 added.
5597 * New native configurations
5599 GNU/Linux/hppa hppa*-*-linux*
5600 OpenBSD/hppa hppa*-*-openbsd*
5601 OpenBSD/m68k m68*-*-openbsd*
5602 OpenBSD/m88k m88*-*-openbsd*
5603 OpenBSD/powerpc powerpc-*-openbsd*
5604 NetBSD/vax vax-*-netbsd*
5605 OpenBSD/vax vax-*-openbsd*
5607 * END-OF-LIFE frame compatibility module
5609 GDB's internal frame infrastructure has been completely rewritten.
5610 The new infrastructure making it possible to support key new features
5611 including DWARF 2 Call Frame Information. To aid in the task of
5612 migrating old configurations to this new infrastructure, a
5613 compatibility module, that allowed old configurations to continue to
5614 work, was also included.
5616 GDB 6.2 will be the last release to include this frame compatibility
5617 module. This change directly impacts the following configurations:
5627 Unless there is activity to revive these configurations, they will be
5628 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
5630 * REMOVED configurations and files
5632 Sun 3, running SunOS 3 m68*-*-sunos3*
5633 Sun 3, running SunOS 4 m68*-*-sunos4*
5634 Sun 2, running SunOS 3 m68000-*-sunos3*
5635 Sun 2, running SunOS 4 m68000-*-sunos4*
5636 Motorola 680x0 running LynxOS m68*-*-lynxos*
5637 AT&T 3b1/Unix pc m68*-att-*
5638 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5639 decstation mips-dec-* mips-little-*
5640 riscos mips-*-riscos* mips-*-sysv*
5641 sonymips mips-sony-*
5642 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5644 *** Changes in GDB 6.1.1:
5646 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
5648 The TUI (Text-mode User Interface) is now built as part of a default
5649 GDB configuration. It is enabled by either selecting the TUI with the
5650 command line option "-i=tui" or by running the separate "gdbtui"
5651 program. For more information on the TUI, see the manual "Debugging
5654 * Pending breakpoint support (also included in GDB 6.1)
5656 Support has been added to allow you to specify breakpoints in shared
5657 libraries that have not yet been loaded. If a breakpoint location
5658 cannot be found, and the "breakpoint pending" option is set to auto,
5659 GDB queries you if you wish to make the breakpoint pending on a future
5660 shared-library load. If and when GDB resolves the breakpoint symbol,
5661 the pending breakpoint is removed as one or more regular breakpoints
5664 Pending breakpoints are very useful for GCJ Java debugging.
5666 * Fixed ISO-C build problems
5668 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
5669 non ISO-C code that stopped them being built using a more strict ISO-C
5670 compiler (e.g., IBM's C compiler).
5672 * Fixed build problem on IRIX 5
5674 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
5675 wasn't able to compile compile on an IRIX 5 system.
5677 * Added execute permission to gdb/gdbserver/configure
5679 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
5680 permission. This bug would cause configure to fail on a number of
5681 systems (Solaris, IRIX). Ref: server/519.
5683 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
5685 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
5686 has been updated to use constant array sizes.
5688 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
5690 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
5691 its generated DWARF Call Frame Info. This encoding was causing GDB to
5692 panic, that panic has been fixed. Ref: gdb/1628.
5694 * Fixed a problem when examining parameters in shared library code.
5696 When examining parameters in optimized shared library code generated
5697 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
5698 not available''. GDB now correctly displays the variable's value.
5700 *** Changes in GDB 6.1:
5702 * Removed --with-mmalloc
5704 Support for the mmalloc memory manager has been removed, as it
5705 conflicted with the internal gdb byte cache.
5707 * Changes in AMD64 configurations
5709 The AMD64 target now includes the %cs and %ss registers. As a result
5710 the AMD64 remote protocol has changed; this affects the floating-point
5711 and SSE registers. If you rely on those registers for your debugging,
5712 you should upgrade gdbserver on the remote side.
5714 * Revised SPARC target
5716 The SPARC target has been completely revised, incorporating the
5717 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
5718 support for LynxOS and SunOS 4 has been dropped. Calling functions
5719 from within GDB on operating systems with a non-executable stack
5720 (Solaris, OpenBSD) now works.
5724 GDB has a new C++ demangler which does a better job on the mangled
5725 names generated by current versions of g++. It also runs faster, so
5726 with this and other changes gdb should now start faster on large C++
5729 * DWARF 2 Location Expressions
5731 GDB support for location expressions has been extended to support function
5732 arguments and frame bases. Older versions of GDB could crash when they
5735 * C++ nested types and namespaces
5737 GDB's support for nested types and namespaces in C++ has been
5738 improved, especially if you use the DWARF 2 debugging format. (This
5739 is the default for recent versions of GCC on most platforms.)
5740 Specifically, if you have a class "Inner" defined within a class or
5741 namespace "Outer", then GDB realizes that the class's name is
5742 "Outer::Inner", not simply "Inner". This should greatly reduce the
5743 frequency of complaints about not finding RTTI symbols. In addition,
5744 if you are stopped at inside of a function defined within a namespace,
5745 GDB modifies its name lookup accordingly.
5747 * New native configurations
5749 NetBSD/amd64 x86_64-*-netbsd*
5750 OpenBSD/amd64 x86_64-*-openbsd*
5751 OpenBSD/alpha alpha*-*-openbsd*
5752 OpenBSD/sparc sparc-*-openbsd*
5753 OpenBSD/sparc64 sparc64-*-openbsd*
5755 * New debugging protocols
5757 M32R with SDI protocol m32r-*-elf*
5759 * "set prompt-escape-char" command deleted.
5761 The command "set prompt-escape-char" has been deleted. This command,
5762 and its very obscure effect on GDB's prompt, was never documented,
5763 tested, nor mentioned in the NEWS file.
5765 * OBSOLETE configurations and files
5767 Configurations that have been declared obsolete in this release have
5768 been commented out. Unless there is activity to revive these
5769 configurations, the next release of GDB will have their sources
5770 permanently REMOVED.
5772 Sun 3, running SunOS 3 m68*-*-sunos3*
5773 Sun 3, running SunOS 4 m68*-*-sunos4*
5774 Sun 2, running SunOS 3 m68000-*-sunos3*
5775 Sun 2, running SunOS 4 m68000-*-sunos4*
5776 Motorola 680x0 running LynxOS m68*-*-lynxos*
5777 AT&T 3b1/Unix pc m68*-att-*
5778 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5779 decstation mips-dec-* mips-little-*
5780 riscos mips-*-riscos* mips-*-sysv*
5781 sonymips mips-sony-*
5782 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5784 * REMOVED configurations and files
5786 SGI Irix-4.x mips-sgi-irix4 or iris4
5787 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5788 Z8000 simulator z8k-zilog-none or z8ksim
5789 Matsushita MN10200 w/simulator mn10200-*-*
5790 H8/500 simulator h8500-hitachi-hms or h8500hms
5791 HP/PA running BSD hppa*-*-bsd*
5792 HP/PA running OSF/1 hppa*-*-osf*
5793 HP/PA Pro target hppa*-*-pro*
5794 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5795 386BSD i[3456]86-*-bsd*
5796 Sequent family i[3456]86-sequent-sysv4*
5797 i[3456]86-sequent-sysv*
5798 i[3456]86-sequent-bsd*
5799 SPARC running LynxOS sparc-*-lynxos*
5800 SPARC running SunOS 4 sparc-*-sunos4*
5801 Tsqware Sparclet sparclet-*-*
5802 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5804 *** Changes in GDB 6.0:
5808 Support for debugging the Objective-C programming language has been
5809 integrated into GDB.
5811 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5813 DWARF 2's Call Frame Information makes available compiler generated
5814 information that more exactly describes the program's run-time stack.
5815 By using this information, GDB is able to provide more robust stack
5818 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5819 have been updated to use a new backtrace mechanism which includes
5820 DWARF 2 CFI support.
5824 GDB's remote protocol has been extended to include support for hosted
5825 file I/O (where the remote target uses GDB's file system). See GDB's
5826 remote protocol documentation for details.
5828 * All targets using the new architecture framework.
5830 All of GDB's targets have been updated to use the new internal
5831 architecture framework. The way is now open for future GDB releases
5832 to include cross-architecture native debugging support (i386 on amd64,
5835 * GNU/Linux's Thread Local Storage (TLS)
5837 GDB now includes support for for the GNU/Linux implementation of
5838 per-thread variables.
5840 * GNU/Linux's Native POSIX Thread Library (NPTL)
5842 GDB's thread code has been updated to work with either the new
5843 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5845 * Separate debug info.
5847 GDB, in conjunction with BINUTILS, now supports a mechanism for
5848 automatically loading debug information from a separate file. Instead
5849 of shipping full debug and non-debug versions of system libraries,
5850 system integrators can now instead ship just the stripped libraries
5851 and optional debug files.
5853 * DWARF 2 Location Expressions
5855 DWARF 2 Location Expressions allow the compiler to more completely
5856 describe the location of variables (even in optimized code) to the
5859 GDB now includes preliminary support for location expressions (support
5860 for DW_OP_piece is still missing).
5864 A number of long standing bugs that caused GDB to die while starting a
5865 Java application have been fixed. GDB's Java support is now
5866 considered "useable".
5868 * GNU/Linux support for fork, vfork, and exec.
5870 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5871 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5874 * GDB supports logging output to a file
5876 There are two new commands, "set logging" and "show logging", which can be
5877 used to capture GDB's output to a file.
5879 * The meaning of "detach" has changed for gdbserver
5881 The "detach" command will now resume the application, as documented. To
5882 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5885 * d10v, m68hc11 `regs' command deprecated
5887 The `info registers' command has been updated so that it displays the
5888 registers using a format identical to the old `regs' command.
5892 A new command, "maint set profile on/off", has been added. This command can
5893 be used to enable or disable profiling while running GDB, to profile a
5894 session or a set of commands. In addition there is a new configure switch,
5895 "--enable-profiling", which will cause GDB to be compiled with profiling
5896 data, for more informative profiling results.
5898 * Default MI syntax changed to "mi2".
5900 The default MI (machine interface) syntax, enabled by the command line
5901 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5902 "mi1", can be enabled by specifying the option "-i=mi1".
5904 Support for the original "mi0" syntax (included in GDB 5.0) has been
5907 Fix for gdb/192: removed extraneous space when displaying frame level.
5908 Fix for gdb/672: update changelist is now output in mi list format.
5909 Fix for gdb/702: a -var-assign that updates the value now shows up
5910 in a subsequent -var-update.
5912 * New native configurations.
5914 FreeBSD/amd64 x86_64-*-freebsd*
5916 * Multi-arched targets.
5918 HP/PA HPUX11 hppa*-*-hpux*
5919 Renesas M32R/D w/simulator m32r-*-elf*
5921 * OBSOLETE configurations and files
5923 Configurations that have been declared obsolete in this release have
5924 been commented out. Unless there is activity to revive these
5925 configurations, the next release of GDB will have their sources
5926 permanently REMOVED.
5928 Z8000 simulator z8k-zilog-none or z8ksim
5929 Matsushita MN10200 w/simulator mn10200-*-*
5930 H8/500 simulator h8500-hitachi-hms or h8500hms
5931 HP/PA running BSD hppa*-*-bsd*
5932 HP/PA running OSF/1 hppa*-*-osf*
5933 HP/PA Pro target hppa*-*-pro*
5934 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5935 Sequent family i[3456]86-sequent-sysv4*
5936 i[3456]86-sequent-sysv*
5937 i[3456]86-sequent-bsd*
5938 Tsqware Sparclet sparclet-*-*
5939 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5941 * REMOVED configurations and files
5944 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5945 IBM AIX PS/2 i[3456]86-*-aix
5946 i386 running Mach 3.0 i[3456]86-*-mach3*
5947 i386 running Mach i[3456]86-*-mach*
5948 i386 running OSF/1 i[3456]86-*osf1mk*
5949 HP/Apollo 68k Family m68*-apollo*-sysv*,
5951 m68*-hp-bsd*, m68*-hp-hpux*
5952 Argonaut Risc Chip (ARC) arc-*-*
5953 Mitsubishi D30V d30v-*-*
5954 Fujitsu FR30 fr30-*-elf*
5955 OS/9000 i[34]86-*-os9k
5956 I960 with MON960 i960-*-coff
5958 * MIPS $fp behavior changed
5960 The convenience variable $fp, for the MIPS, now consistently returns
5961 the address of the current frame's base. Previously, depending on the
5962 context, $fp could refer to either $sp or the current frame's base
5963 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5964 The GNU Source-Level Debugger''.
5966 *** Changes in GDB 5.3:
5968 * GNU/Linux shared library multi-threaded performance improved.
5970 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5971 `/proc', in preference to `ptrace' for memory reads. This may result
5972 in an improvement in the start-up time of multi-threaded, shared
5973 library applications when run under GDB. One GDB user writes: ``loads
5974 shared libs like mad''.
5976 * ``gdbserver'' now supports multi-threaded applications on some targets
5978 Support for debugging multi-threaded applications which use
5979 the GNU/Linux LinuxThreads package has been added for
5980 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5981 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5983 * GDB now supports C/C++ preprocessor macros.
5985 GDB now expands preprocessor macro invocations in C/C++ expressions,
5986 and provides various commands for showing macro definitions and how
5989 The new command `macro expand EXPRESSION' expands any macro
5990 invocations in expression, and shows the result.
5992 The new command `show macro MACRO-NAME' shows the definition of the
5993 macro named MACRO-NAME, and where it was defined.
5995 Most compilers don't include information about macros in the debugging
5996 information by default. In GCC 3.1, for example, you need to compile
5997 your program with the options `-gdwarf-2 -g3'. If the macro
5998 information is present in the executable, GDB will read it.
6000 * Multi-arched targets.
6002 DEC Alpha (partial) alpha*-*-*
6003 DEC VAX (partial) vax-*-*
6005 National Semiconductor NS32000 (partial) ns32k-*-*
6006 Motorola 68000 (partial) m68k-*-*
6007 Motorola MCORE mcore-*-*
6011 Fujitsu FRV architecture added by Red Hat frv*-*-*
6014 * New native configurations
6016 Alpha NetBSD alpha*-*-netbsd*
6017 SH NetBSD sh*-*-netbsdelf*
6018 MIPS NetBSD mips*-*-netbsd*
6019 UltraSPARC NetBSD sparc64-*-netbsd*
6021 * OBSOLETE configurations and files
6023 Configurations that have been declared obsolete in this release have
6024 been commented out. Unless there is activity to revive these
6025 configurations, the next release of GDB will have their sources
6026 permanently REMOVED.
6028 Mitsubishi D30V d30v-*-*
6029 OS/9000 i[34]86-*-os9k
6030 IBM AIX PS/2 i[3456]86-*-aix
6031 Fujitsu FR30 fr30-*-elf*
6032 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6033 Argonaut Risc Chip (ARC) arc-*-*
6034 i386 running Mach 3.0 i[3456]86-*-mach3*
6035 i386 running Mach i[3456]86-*-mach*
6036 i386 running OSF/1 i[3456]86-*osf1mk*
6037 HP/Apollo 68k Family m68*-apollo*-sysv*,
6039 m68*-hp-bsd*, m68*-hp-hpux*
6040 I960 with MON960 i960-*-coff
6042 * OBSOLETE languages
6044 CHILL, a Pascal like language used by telecommunications companies.
6046 * REMOVED configurations and files
6048 AMD 29k family via UDI a29k-amd-udi, udi29k
6049 A29K VxWorks a29k-*-vxworks
6050 AMD 29000 embedded, using EBMON a29k-none-none
6051 AMD 29000 embedded with COFF a29k-none-coff
6052 AMD 29000 embedded with a.out a29k-none-aout
6054 testsuite/gdb.hp/gdb.threads-hp/ directory
6056 * New command "set max-user-call-depth <nnn>"
6058 This command allows the user to limit the call depth of user-defined
6059 commands. The default is 1024.
6061 * Changes in FreeBSD/i386 native debugging.
6063 Support for the "generate-core-file" has been added.
6065 * New commands "dump", "append", and "restore".
6067 These commands allow data to be copied from target memory
6068 to a bfd-format or binary file (dump and append), and back
6069 from a file into memory (restore).
6071 * Improved "next/step" support on multi-processor Alpha Tru64.
6073 The previous single-step mechanism could cause unpredictable problems,
6074 including the random appearance of SIGSEGV or SIGTRAP signals. The use
6075 of a software single-step mechanism prevents this.
6077 *** Changes in GDB 5.2.1:
6085 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
6086 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
6087 Fix, by Joel Brobecker imported from mainline.
6089 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
6090 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
6091 Fix, by Fred Fish, imported from mainline.
6093 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
6094 Surprisingly enough, it works now.
6095 By Michal Ludvig, imported from mainline.
6097 i386 hardware watchpoint support:
6098 avoid misses on second run for some targets.
6099 By Pierre Muller, imported from mainline.
6101 *** Changes in GDB 5.2:
6103 * New command "set trust-readonly-sections on[off]".
6105 This command is a hint that tells gdb that read-only sections
6106 really are read-only (ie. that their contents will not change).
6107 In this mode, gdb will go to the object file rather than the
6108 target to read memory from read-only sections (such as ".text").
6109 This can be a significant performance improvement on some
6110 (notably embedded) targets.
6112 * New command "generate-core-file" (or "gcore").
6114 This new gdb command allows the user to drop a core file of the child
6115 process state at any time. So far it's been implemented only for
6116 GNU/Linux and Solaris, but should be relatively easily ported to other
6117 hosts. Argument is core file name (defaults to core.<pid>).
6119 * New command line option
6121 GDB now accepts --pid or -p followed by a process id.
6123 * Change in command line behavior -- corefiles vs. process ids.
6125 There is a subtle behavior in the way in which GDB handles
6126 command line arguments. The first non-flag argument is always
6127 a program to debug, but the second non-flag argument may either
6128 be a corefile or a process id. Previously, GDB would attempt to
6129 open the second argument as a corefile, and if that failed, would
6130 issue a superfluous error message and then attempt to attach it as
6131 a process. Now, if the second argument begins with a non-digit,
6132 it will be treated as a corefile. If it begins with a digit,
6133 GDB will attempt to attach it as a process, and if no such process
6134 is found, will then attempt to open it as a corefile.
6136 * Changes in ARM configurations.
6138 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
6139 configuration is fully multi-arch.
6141 * New native configurations
6143 ARM NetBSD arm*-*-netbsd*
6144 x86 OpenBSD i[3456]86-*-openbsd*
6145 AMD x86-64 running GNU/Linux x86_64-*-linux-*
6146 Sparc64 running FreeBSD sparc64-*-freebsd*
6150 Sanyo XStormy16 xstormy16-elf
6152 * OBSOLETE configurations and files
6154 Configurations that have been declared obsolete in this release have
6155 been commented out. Unless there is activity to revive these
6156 configurations, the next release of GDB will have their sources
6157 permanently REMOVED.
6159 AMD 29k family via UDI a29k-amd-udi, udi29k
6160 A29K VxWorks a29k-*-vxworks
6161 AMD 29000 embedded, using EBMON a29k-none-none
6162 AMD 29000 embedded with COFF a29k-none-coff
6163 AMD 29000 embedded with a.out a29k-none-aout
6165 testsuite/gdb.hp/gdb.threads-hp/ directory
6167 * REMOVED configurations and files
6169 TI TMS320C80 tic80-*-*
6171 PowerPC Solaris powerpcle-*-solaris*
6172 PowerPC Windows NT powerpcle-*-cygwin32
6173 PowerPC Netware powerpc-*-netware*
6174 Harris/CXUX m88k m88*-harris-cxux*
6175 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
6176 ns32k-utek-sysv* ns32k-utek-*
6177 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
6178 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
6179 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
6180 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
6181 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
6183 * Changes to command line processing
6185 The new `--args' feature can be used to specify command-line arguments
6186 for the inferior from gdb's command line.
6188 * Changes to key bindings
6190 There is a new `operate-and-get-next' function bound to `C-o'.
6192 *** Changes in GDB 5.1.1
6194 Fix compile problem on DJGPP.
6196 Fix a problem with floating-point registers on the i386 being
6199 Fix to stop GDB crashing on .debug_str debug info.
6201 Numerous documentation fixes.
6203 Numerous testsuite fixes.
6205 *** Changes in GDB 5.1:
6207 * New native configurations
6209 Alpha FreeBSD alpha*-*-freebsd*
6210 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
6211 MIPS GNU/Linux mips*-*-linux*
6212 MIPS SGI Irix 6.x mips*-sgi-irix6*
6213 ia64 AIX ia64-*-aix*
6214 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
6218 Motorola 68HC11 and 68HC12 m68hc11-elf
6220 UltraSparc running GNU/Linux sparc64-*-linux*
6222 * OBSOLETE configurations and files
6224 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
6225 Harris/CXUX m88k m88*-harris-cxux*
6226 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
6227 ns32k-utek-sysv* ns32k-utek-*
6228 TI TMS320C80 tic80-*-*
6230 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
6231 PowerPC Solaris powerpcle-*-solaris*
6232 PowerPC Windows NT powerpcle-*-cygwin32
6233 PowerPC Netware powerpc-*-netware*
6234 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
6235 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
6236 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
6237 Apple Macintosh (MPW) host N/A
6239 stuff.c (Program to stuff files into a specially prepared space in kdb)
6240 kdb-start.c (Main loop for the standalone kernel debugger)
6242 Configurations that have been declared obsolete in this release have
6243 been commented out. Unless there is activity to revive these
6244 configurations, the next release of GDB will have their sources
6245 permanently REMOVED.
6247 * REMOVED configurations and files
6249 Altos 3068 m68*-altos-*
6250 Convex c1-*-*, c2-*-*
6252 ARM RISCix arm-*-* (as host)
6256 * GDB has been converted to ISO C.
6258 GDB's source code has been converted to ISO C. In particular, the
6259 sources are fully protoized, and rely on standard headers being
6264 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
6266 * The MI enabled by default.
6268 The new machine oriented interface (MI) introduced in GDB 5.0 has been
6269 revised and enabled by default. Packages which use GDB as a debugging
6270 engine behind a UI or another front end are encouraged to switch to
6271 using the GDB/MI interface, instead of the old annotations interface
6272 which is now deprecated.
6274 * Support for debugging Pascal programs.
6276 GDB now includes support for debugging Pascal programs. The following
6277 main features are supported:
6279 - Pascal-specific data types such as sets;
6281 - automatic recognition of Pascal sources based on file-name
6284 - Pascal-style display of data types, variables, and functions;
6286 - a Pascal expression parser.
6288 However, some important features are not yet supported.
6290 - Pascal string operations are not supported at all;
6292 - there are some problems with boolean types;
6294 - Pascal type hexadecimal constants are not supported
6295 because they conflict with the internal variables format;
6297 - support for Pascal objects and classes is not full yet;
6299 - unlike Pascal, GDB is case-sensitive for symbol names.
6301 * Changes in completion.
6303 Commands such as `shell', `run' and `set args', which pass arguments
6304 to inferior programs, now complete on file names, similar to what
6305 users expect at the shell prompt.
6307 Commands which accept locations, such as `disassemble', `print',
6308 `breakpoint', `until', etc. now complete on filenames as well as
6309 program symbols. Thus, if you type "break foob TAB", and the source
6310 files linked into the programs include `foobar.c', that file name will
6311 be one of the candidates for completion. However, file names are not
6312 considered for completion after you typed a colon that delimits a file
6313 name from a name of a function in that file, as in "break foo.c:bar".
6315 `set demangle-style' completes on available demangling styles.
6317 * New platform-independent commands:
6319 It is now possible to define a post-hook for a command as well as a
6320 hook that runs before the command. For more details, see the
6321 documentation of `hookpost' in the GDB manual.
6323 * Changes in GNU/Linux native debugging.
6325 Support for debugging multi-threaded programs has been completely
6326 revised for all platforms except m68k and sparc. You can now debug as
6327 many threads as your system allows you to have.
6329 Attach/detach is supported for multi-threaded programs.
6331 Support for SSE registers was added for x86. This doesn't work for
6332 multi-threaded programs though.
6334 * Changes in MIPS configurations.
6336 Multi-arch support is enabled for all MIPS configurations.
6338 GDB can now be built as native debugger on SGI Irix 6.x systems for
6339 debugging n32 executables. (Debugging 64-bit executables is not yet
6342 * Unified support for hardware watchpoints in all x86 configurations.
6344 Most (if not all) native x86 configurations support hardware-assisted
6345 breakpoints and watchpoints in a unified manner. This support
6346 implements debug register sharing between watchpoints, which allows to
6347 put a virtually infinite number of watchpoints on the same address,
6348 and also supports watching regions up to 16 bytes with several debug
6351 The new maintenance command `maintenance show-debug-regs' toggles
6352 debugging print-outs in functions that insert, remove, and test
6353 watchpoints and hardware breakpoints.
6355 * Changes in the DJGPP native configuration.
6357 New command ``info dos sysinfo'' displays assorted information about
6358 the CPU, OS, memory, and DPMI server.
6360 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
6361 display information about segment descriptors stored in GDT, LDT, and
6364 New commands ``info dos pde'' and ``info dos pte'' display entries
6365 from Page Directory and Page Tables (for now works with CWSDPMI only).
6366 New command ``info dos address-pte'' displays the Page Table entry for
6367 a given linear address.
6369 GDB can now pass command lines longer than 126 characters to the
6370 program being debugged (requires an update to the libdbg.a library
6371 which is part of the DJGPP development kit).
6373 DWARF2 debug info is now supported.
6375 It is now possible to `step' and `next' through calls to `longjmp'.
6377 * Changes in documentation.
6379 All GDB documentation was converted to GFDL, the GNU Free
6380 Documentation License.
6382 Tracepoints-related commands are now fully documented in the GDB
6385 TUI, the Text-mode User Interface, is now documented in the manual.
6387 Tracepoints-related commands are now fully documented in the GDB
6390 The "GDB Internals" manual now has an index. It also includes
6391 documentation of `ui_out' functions, GDB coding standards, x86
6392 hardware watchpoints, and memory region attributes.
6394 * GDB's version number moved to ``version.in''
6396 The Makefile variable VERSION has been replaced by the file
6397 ``version.in''. People creating GDB distributions should update the
6398 contents of this file.
6402 GUD support is now a standard part of the EMACS distribution.
6404 *** Changes in GDB 5.0:
6406 * Improved support for debugging FP programs on x86 targets
6408 Unified and much-improved support for debugging floating-point
6409 programs on all x86 targets. In particular, ``info float'' now
6410 displays the FP registers in the same format on all x86 targets, with
6411 greater level of detail.
6413 * Improvements and bugfixes in hardware-assisted watchpoints
6415 It is now possible to watch array elements, struct members, and
6416 bitfields with hardware-assisted watchpoints. Data-read watchpoints
6417 on x86 targets no longer erroneously trigger when the address is
6420 * Improvements in the native DJGPP version of GDB
6422 The distribution now includes all the scripts and auxiliary files
6423 necessary to build the native DJGPP version on MS-DOS/MS-Windows
6424 machines ``out of the box''.
6426 The DJGPP version can now debug programs that use signals. It is
6427 possible to catch signals that happened in the debuggee, deliver
6428 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
6429 would kill the program being debugged.) Programs that hook hardware
6430 interrupts (keyboard, timer, etc.) can also be debugged.
6432 It is now possible to debug DJGPP programs that redirect their
6433 standard handles or switch them to raw (as opposed to cooked) mode, or
6434 even close them. The command ``run < foo > bar'' works as expected,
6435 and ``info terminal'' reports useful information about the debuggee's
6436 terminal, including raw/cooked mode, redirection, etc.
6438 The DJGPP version now uses termios functions for console I/O, which
6439 enables debugging graphics programs. Interrupting GDB with Ctrl-C
6442 DOS-style file names with drive letters are now fully supported by
6445 It is now possible to debug DJGPP programs that switch their working
6446 directory. It is also possible to rerun the debuggee any number of
6447 times without restarting GDB; thus, you can use the same setup,
6448 breakpoints, etc. for many debugging sessions.
6450 * New native configurations
6452 ARM GNU/Linux arm*-*-linux*
6453 PowerPC GNU/Linux powerpc-*-linux*
6457 Motorola MCore mcore-*-*
6458 x86 VxWorks i[3456]86-*-vxworks*
6459 PowerPC VxWorks powerpc-*-vxworks*
6460 TI TMS320C80 tic80-*-*
6462 * OBSOLETE configurations
6464 Altos 3068 m68*-altos-*
6465 Convex c1-*-*, c2-*-*
6467 ARM RISCix arm-*-* (as host)
6470 Configurations that have been declared obsolete will be commented out,
6471 but the code will be left in place. If there is no activity to revive
6472 these configurations before the next release of GDB, the sources will
6473 be permanently REMOVED.
6475 * Gould support removed
6477 Support for the Gould PowerNode and NP1 has been removed.
6479 * New features for SVR4
6481 On SVR4 native platforms (such as Solaris), if you attach to a process
6482 without first loading a symbol file, GDB will now attempt to locate and
6483 load symbols from the running process's executable file.
6485 * Many C++ enhancements
6487 C++ support has been greatly improved. Overload resolution now works properly
6488 in almost all cases. RTTI support is on the way.
6490 * Remote targets can connect to a sub-program
6492 A popen(3) style serial-device has been added. This device starts a
6493 sub-process (such as a stand-alone simulator) and then communicates
6494 with that. The sub-program to run is specified using the syntax
6495 ``|<program> <args>'' vis:
6497 (gdb) set remotedebug 1
6498 (gdb) target extended-remote |mn10300-elf-sim program-args
6500 * MIPS 64 remote protocol
6502 A long standing bug in the mips64 remote protocol where by GDB
6503 expected certain 32 bit registers (ex SR) to be transfered as 32
6504 instead of 64 bits has been fixed.
6506 The command ``set remote-mips64-transfers-32bit-regs on'' has been
6507 added to provide backward compatibility with older versions of GDB.
6509 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
6511 The command ``set remotebinarydownload'' command has been replaced by
6512 ``set remote X-packet''. Other commands in ``set remote'' family
6513 include ``set remote P-packet''.
6515 * Breakpoint commands accept ranges.
6517 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
6518 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
6519 ``tracepoint passcount'' also accepts a range of tracepoints.
6521 * ``apropos'' command added.
6523 The ``apropos'' command searches through command names and
6524 documentation strings, printing out matches, making it much easier to
6525 try to find a command that does what you are looking for.
6529 A new machine oriented interface (MI) has been added to GDB. This
6530 interface is designed for debug environments running GDB as a separate
6531 process. This is part of the long term libGDB project. See the
6532 "GDB/MI" chapter of the GDB manual for further information. It can be
6533 enabled by configuring with:
6535 .../configure --enable-gdbmi
6537 *** Changes in GDB-4.18:
6539 * New native configurations
6541 HP-UX 10.20 hppa*-*-hpux10.20
6542 HP-UX 11.x hppa*-*-hpux11.0*
6543 M68K GNU/Linux m68*-*-linux*
6547 Fujitsu FR30 fr30-*-elf*
6548 Intel StrongARM strongarm-*-*
6549 Mitsubishi D30V d30v-*-*
6551 * OBSOLETE configurations
6553 Gould PowerNode, NP1 np1-*-*, pn-*-*
6555 Configurations that have been declared obsolete will be commented out,
6556 but the code will be left in place. If there is no activity to revive
6557 these configurations before the next release of GDB, the sources will
6558 be permanently REMOVED.
6562 As a compatibility experiment, GDB's source files buildsym.h and
6563 buildsym.c have been converted to pure standard C, no longer
6564 containing any K&R compatibility code. We believe that all systems in
6565 use today either come with a standard C compiler, or have a GCC port
6566 available. If this is not true, please report the affected
6567 configuration to bug-gdb@gnu.org immediately. See the README file for
6568 information about getting a standard C compiler if you don't have one
6573 GDB now uses readline 2.2.
6575 * set extension-language
6577 You can now control the mapping between filename extensions and source
6578 languages by using the `set extension-language' command. For instance,
6579 you can ask GDB to treat .c files as C++ by saying
6580 set extension-language .c c++
6581 The command `info extensions' lists all of the recognized extensions
6582 and their associated languages.
6584 * Setting processor type for PowerPC and RS/6000
6586 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
6587 you can use the `set processor' command to specify what variant of the
6588 PowerPC family you are debugging. The command
6592 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
6593 following PowerPC and RS6000 variants:
6595 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
6596 rs6000 IBM RS6000 ("POWER") architecture, user-level view
6598 403GC IBM PowerPC 403GC
6599 505 Motorola PowerPC 505
6600 860 Motorola PowerPC 860 or 850
6601 601 Motorola PowerPC 601
6602 602 Motorola PowerPC 602
6603 603 Motorola/IBM PowerPC 603 or 603e
6604 604 Motorola PowerPC 604 or 604e
6605 750 Motorola/IBM PowerPC 750 or 750
6607 At the moment, this command just tells GDB what to name the
6608 special-purpose processor registers. Since almost all the affected
6609 registers are inaccessible to user-level programs, this command is
6610 only useful for remote debugging in its present form.
6614 Thanks to a major code donation from Hewlett-Packard, GDB now has much
6615 more extensive support for HP-UX. Added features include shared
6616 library support, kernel threads and hardware watchpoints for 11.00,
6617 support for HP's ANSI C and C++ compilers, and a compatibility mode
6618 for xdb and dbx commands.
6622 HP's donation includes the new concept of catchpoints, which is a
6623 generalization of the old catch command. On HP-UX, it is now possible
6624 to catch exec, fork, and vfork, as well as library loading.
6626 This means that the existing catch command has changed; its first
6627 argument now specifies the type of catch to be set up. See the
6628 output of "help catch" for a list of catchpoint types.
6630 * Debugging across forks
6632 On HP-UX, you can choose which process to debug when a fork() happens
6637 HP has donated a curses-based terminal user interface (TUI). To get
6638 it, build with --enable-tui. Although this can be enabled for any
6639 configuration, at present it only works for native HP debugging.
6641 * GDB remote protocol additions
6643 A new protocol packet 'X' that writes binary data is now available.
6644 Default behavior is to try 'X', then drop back to 'M' if the stub
6645 fails to respond. The settable variable `remotebinarydownload'
6646 allows explicit control over the use of 'X'.
6648 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
6649 full 64-bit address. The command
6651 set remoteaddresssize 32
6653 can be used to revert to the old behaviour. For existing remote stubs
6654 the change should not be noticed, as the additional address information
6657 In order to assist in debugging stubs, you may use the maintenance
6658 command `packet' to send any text string to the stub. For instance,
6660 maint packet heythere
6662 sends the packet "$heythere#<checksum>". Note that it is very easy to
6663 disrupt a debugging session by sending the wrong packet at the wrong
6666 The compare-sections command allows you to compare section data on the
6667 target to what is in the executable file without uploading or
6668 downloading, by comparing CRC checksums.
6670 * Tracing can collect general expressions
6672 You may now collect general expressions at tracepoints. This requires
6673 further additions to the target-side stub; see tracepoint.c and
6674 doc/agentexpr.texi for further details.
6676 * mask-address variable for Mips
6678 For Mips targets, you may control the zeroing of the upper 32 bits of
6679 a 64-bit address by entering `set mask-address on'. This is mainly
6680 of interest to users of embedded R4xxx and R5xxx processors.
6682 * Higher serial baud rates
6684 GDB's serial code now allows you to specify baud rates 57600, 115200,
6685 230400, and 460800 baud. (Note that your host system may not be able
6686 to achieve all of these rates.)
6690 The i960 configuration now includes an initial implementation of a
6691 builtin simulator, contributed by Jim Wilson.
6694 *** Changes in GDB-4.17:
6696 * New native configurations
6698 Alpha GNU/Linux alpha*-*-linux*
6699 Unixware 2.x i[3456]86-unixware2*
6700 Irix 6.x mips*-sgi-irix6*
6701 PowerPC GNU/Linux powerpc-*-linux*
6702 PowerPC Solaris powerpcle-*-solaris*
6703 Sparc GNU/Linux sparc-*-linux*
6704 Motorola sysV68 R3V7.1 m68k-motorola-sysv
6708 Argonaut Risc Chip (ARC) arc-*-*
6709 Hitachi H8/300S h8300*-*-*
6710 Matsushita MN10200 w/simulator mn10200-*-*
6711 Matsushita MN10300 w/simulator mn10300-*-*
6712 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
6713 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
6714 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
6715 Mitsubishi D10V w/simulator d10v-*-*
6716 Mitsubishi M32R/D w/simulator m32r-*-elf*
6717 Tsqware Sparclet sparclet-*-*
6718 NEC V850 w/simulator v850-*-*
6720 * New debugging protocols
6722 ARM with RDI protocol arm*-*-*
6723 M68K with dBUG monitor m68*-*-{aout,coff,elf}
6724 DDB and LSI variants of PMON protocol mips*-*-*
6725 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
6726 PowerPC with SDS protocol powerpc{,le}-*-eabi
6727 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6731 All configurations can now understand and use the DWARF 2 debugging
6732 format. The choice is automatic, if the symbol file contains DWARF 2
6737 GDB now includes basic Java language support. This support is
6738 only useful with Java compilers that produce native machine code.
6740 * solib-absolute-prefix and solib-search-path
6742 For SunOS and SVR4 shared libraries, you may now set the prefix for
6743 loading absolute shared library symbol files, and the search path for
6744 locating non-absolute shared library symbol files.
6746 * Live range splitting
6748 GDB can now effectively debug code for which GCC has performed live
6749 range splitting as part of its optimization. See gdb/doc/LRS for
6750 more details on the expected format of the stabs information.
6754 GDB's support for the GNU Hurd, including thread debugging, has been
6755 updated to work with current versions of the Hurd.
6759 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6760 instruction set. ARM GDB automatically detects when Thumb
6761 instructions are in use, and adjusts disassembly and backtracing
6766 GDB's MIPS target configurations now handle the MIP16 16-bit
6771 GDB now includes support for overlays; if an executable has been
6772 linked such that multiple sections are based at the same address, GDB
6773 will decide which section to use for symbolic info. You can choose to
6774 control the decision manually, using overlay commands, or implement
6775 additional target-side support and use "overlay load-target" to bring
6776 in the overlay mapping. Do "help overlay" for more detail.
6780 The command "info symbol <address>" displays information about
6781 the symbol at the specified address.
6785 The standard remote protocol now includes an extension that allows
6786 asynchronous collection and display of trace data. This requires
6787 extensive support in the target-side debugging stub. Tracing mode
6788 includes a new interaction mode in GDB and new commands: see the
6789 file tracepoint.c for more details.
6793 Configurations for embedded MIPS now include a simulator contributed
6794 by Cygnus Solutions. The simulator supports the instruction sets
6795 of most MIPS variants.
6799 Sparc configurations may now include the ERC32 simulator contributed
6800 by the European Space Agency. The simulator is not built into
6801 Sparc targets by default; configure with --enable-sim to include it.
6805 For target configurations that may include multiple variants of a
6806 basic architecture (such as MIPS and SH), you may now set the
6807 architecture explicitly. "set arch" sets, "info arch" lists
6808 the possible architectures.
6810 *** Changes in GDB-4.16:
6812 * New native configurations
6814 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6815 M68K NetBSD m68k-*-netbsd*
6816 PowerPC AIX 4.x powerpc-*-aix*
6817 PowerPC MacOS powerpc-*-macos*
6818 PowerPC Windows NT powerpcle-*-cygwin32
6819 RS/6000 AIX 4.x rs6000-*-aix4*
6823 ARM with RDP protocol arm-*-*
6824 I960 with MON960 i960-*-coff
6825 MIPS VxWorks mips*-*-vxworks*
6826 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6827 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6829 Matra Sparclet sparclet-*-*
6833 The powerpc-eabi configuration now includes the PSIM simulator,
6834 contributed by Andrew Cagney, with assistance from Mike Meissner.
6835 PSIM is a very elaborate model of the PowerPC, including not only
6836 basic instruction set execution, but also details of execution unit
6837 performance and I/O hardware. See sim/ppc/README for more details.
6841 GDB now works with Solaris 2.5.
6843 * Windows 95/NT native
6845 GDB will now work as a native debugger on Windows 95 and Windows NT.
6846 To build it from source, you must use the "gnu-win32" environment,
6847 which uses a DLL to emulate enough of Unix to run the GNU tools.
6848 Further information, binaries, and sources are available at
6849 ftp.cygnus.com, under pub/gnu-win32.
6851 * dont-repeat command
6853 If a user-defined command includes the command `dont-repeat', then the
6854 command will not be repeated if the user just types return. This is
6855 useful if the command is time-consuming to run, so that accidental
6856 extra keystrokes don't run the same command many times.
6858 * Send break instead of ^C
6860 The standard remote protocol now includes an option to send a break
6861 rather than a ^C to the target in order to interrupt it. By default,
6862 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6864 * Remote protocol timeout
6866 The standard remote protocol includes a new variable `remotetimeout'
6867 that allows you to set the number of seconds before GDB gives up trying
6868 to read from the target. The default value is 2.
6870 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6872 By default GDB will automatically keep track of objects as they are
6873 loaded and unloaded by the dynamic linker. By using the command `set
6874 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6875 when shared library events occur, thus allowing you to set breakpoints
6876 in shared libraries which are explicitly loaded by the inferior.
6878 Note this feature does not work on hpux8. On hpux9 you must link
6879 /usr/lib/end.o into your program. This feature should work
6880 automatically on hpux10.
6882 * Irix 5.x hardware watchpoint support
6884 Irix 5 configurations now support the use of hardware watchpoints.
6886 * Mips protocol "SYN garbage limit"
6888 When debugging a Mips target using the `target mips' protocol, you
6889 may set the number of characters that GDB will ignore by setting
6890 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6891 every character. The default value is 1050.
6893 * Recording and replaying remote debug sessions
6895 If you set `remotelogfile' to the name of a file, gdb will write to it
6896 a recording of a remote debug session. This recording may then be
6897 replayed back to gdb using "gdbreplay". See gdbserver/README for
6898 details. This is useful when you have a problem with GDB while doing
6899 remote debugging; you can make a recording of the session and send it
6900 to someone else, who can then recreate the problem.
6902 * Speedups for remote debugging
6904 GDB includes speedups for downloading and stepping MIPS systems using
6905 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6906 and more efficient S-record downloading.
6908 * Memory use reductions and statistics collection
6910 GDB now uses less memory and reports statistics about memory usage.
6911 Try the `maint print statistics' command, for example.
6913 *** Changes in GDB-4.15:
6915 * Psymtabs for XCOFF
6917 The symbol reader for AIX GDB now uses partial symbol tables. This
6918 can greatly improve startup time, especially for large executables.
6920 * Remote targets use caching
6922 Remote targets now use a data cache to speed up communication with the
6923 remote side. The data cache could lead to incorrect results because
6924 it doesn't know about volatile variables, thus making it impossible to
6925 debug targets which use memory mapped I/O devices. `set remotecache
6926 off' turns the data cache off.
6928 * Remote targets may have threads
6930 The standard remote protocol now includes support for multiple threads
6931 in the target system, using new protocol commands 'H' and 'T'. See
6932 gdb/remote.c for details.
6936 If GDB is configured with `--enable-netrom', then it will include
6937 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6938 acts as though it is a bank of ROM on the target board, but you can
6939 write into it over the network. GDB's support consists only of
6940 support for fast loading into the emulated ROM; to debug, you must use
6941 another protocol, such as standard remote protocol. The usual
6942 sequence is something like
6944 target nrom <netrom-hostname>
6946 target remote <netrom-hostname>:1235
6950 GDB now includes support for the Apple Macintosh, as a host only. It
6951 may be run as either an MPW tool or as a standalone application, and
6952 it can debug through the serial port. All the usual GDB commands are
6953 available, but to the target command, you must supply "serial" as the
6954 device type instead of "/dev/ttyXX". See mpw-README in the main
6955 directory for more information on how to build. The MPW configuration
6956 scripts */mpw-config.in support only a few targets, and only the
6957 mips-idt-ecoff target has been tested.
6961 GDB configuration now uses autoconf. This is not user-visible,
6962 but does simplify configuration and building.
6966 GDB now supports hpux10.
6968 *** Changes in GDB-4.14:
6970 * New native configurations
6972 x86 FreeBSD i[345]86-*-freebsd
6973 x86 NetBSD i[345]86-*-netbsd
6974 NS32k NetBSD ns32k-*-netbsd
6975 Sparc NetBSD sparc-*-netbsd
6979 A29K VxWorks a29k-*-vxworks
6980 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6981 CPU32 EST-300 emulator m68*-*-est*
6982 PowerPC ELF powerpc-*-elf
6985 * Alpha OSF/1 support for procfs
6987 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6988 possible to attach to running processes. As the mounting of the /proc
6989 filesystem is optional on the Alpha, GDB automatically determines
6990 the availability of /proc during startup. This can lead to problems
6991 if /proc is unmounted after GDB has been started.
6993 * Arguments to user-defined commands
6995 User commands may accept up to 10 arguments separated by whitespace.
6996 Arguments are accessed within the user command via $arg0..$arg9. A
6999 print $arg0 + $arg1 + $arg2
7001 To execute the command use:
7004 Defines the command "adder" which prints the sum of its three arguments.
7005 Note the arguments are text substitutions, so they may reference variables,
7006 use complex expressions, or even perform inferior function calls.
7008 * New `if' and `while' commands
7010 This makes it possible to write more sophisticated user-defined
7011 commands. Both commands take a single argument, which is the
7012 expression to evaluate, and must be followed by the commands to
7013 execute, one per line, if the expression is nonzero, the list being
7014 terminated by the word `end'. The `if' command list may include an
7015 `else' word, which causes the following commands to be executed only
7016 if the expression is zero.
7018 * Fortran source language mode
7020 GDB now includes partial support for Fortran 77. It will recognize
7021 Fortran programs and can evaluate a subset of Fortran expressions, but
7022 variables and functions may not be handled correctly. GDB will work
7023 with G77, but does not yet know much about symbols emitted by other
7026 * Better HPUX support
7028 Most debugging facilities now work on dynamic executables for HPPAs
7029 running hpux9 or later. You can attach to running dynamically linked
7030 processes, but by default the dynamic libraries will be read-only, so
7031 for instance you won't be able to put breakpoints in them. To change
7032 that behavior do the following before running the program:
7038 This will cause the libraries to be mapped private and read-write.
7039 To revert to the normal behavior, do this:
7045 You cannot set breakpoints or examine data in the library until after
7046 the library is loaded if the function/data symbols do not have
7049 GDB can now also read debug symbols produced by the HP C compiler on
7050 HPPAs (sorry, no C++, Fortran or 68k support).
7052 * Target byte order now dynamically selectable
7054 You can choose which byte order to use with a target system, via the
7055 commands "set endian big" and "set endian little", and you can see the
7056 current setting by using "show endian". You can also give the command
7057 "set endian auto", in which case GDB will use the byte order
7058 associated with the executable. Currently, only embedded MIPS
7059 configurations support dynamic selection of target byte order.
7061 * New DOS host serial code
7063 This version uses DPMI interrupts to handle buffered I/O, so you
7064 no longer need to run asynctsr when debugging boards connected to
7067 *** Changes in GDB-4.13:
7069 * New "complete" command
7071 This lists all the possible completions for the rest of the line, if it
7072 were to be given as a command itself. This is intended for use by emacs.
7074 * Trailing space optional in prompt
7076 "set prompt" no longer adds a space for you after the prompt you set. This
7077 allows you to set a prompt which ends in a space or one that does not.
7079 * Breakpoint hit counts
7081 "info break" now displays a count of the number of times the breakpoint
7082 has been hit. This is especially useful in conjunction with "ignore"; you
7083 can ignore a large number of breakpoint hits, look at the breakpoint info
7084 to see how many times the breakpoint was hit, then run again, ignoring one
7085 less than that number, and this will get you quickly to the last hit of
7088 * Ability to stop printing at NULL character
7090 "set print null-stop" will cause GDB to stop printing the characters of
7091 an array when the first NULL is encountered. This is useful when large
7092 arrays actually contain only short strings.
7094 * Shared library breakpoints
7096 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
7097 breakpoints in shared libraries before the executable is run.
7099 * Hardware watchpoints
7101 There is a new hardware breakpoint for the watch command for sparclite
7102 targets. See gdb/sparclite/hw_breakpoint.note.
7104 Hardware watchpoints are also now supported under GNU/Linux.
7108 Annotations have been added. These are for use with graphical interfaces,
7109 and are still experimental. Currently only gdba.el uses these.
7111 * Improved Irix 5 support
7113 GDB now works properly with Irix 5.2.
7115 * Improved HPPA support
7117 GDB now works properly with the latest GCC and GAS.
7119 * New native configurations
7121 Sequent PTX4 i[34]86-sequent-ptx4
7122 HPPA running OSF/1 hppa*-*-osf*
7123 Atari TT running SVR4 m68*-*-sysv4*
7124 RS/6000 LynxOS rs6000-*-lynxos*
7128 OS/9000 i[34]86-*-os9k
7129 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
7132 * Hitachi SH7000 and E7000-PC ICE support
7134 There is now support for communicating with the Hitachi E7000-PC ICE.
7135 This is available automatically when GDB is configured for the SH.
7139 As usual, a variety of small fixes and improvements, both generic
7140 and configuration-specific. See the ChangeLog for more detail.
7142 *** Changes in GDB-4.12:
7144 * Irix 5 is now supported
7148 GDB-4.12 on the HPPA has a number of changes which make it unable
7149 to debug the output from the currently released versions of GCC and
7150 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
7151 of GCC and GAS, versions of these tools designed to work with GDB-4.12
7152 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
7155 *** Changes in GDB-4.11:
7157 * User visible changes:
7161 The "set remotedebug" option is now consistent between the mips remote
7162 target, remote targets using the gdb-specific protocol, UDI (AMD's
7163 debug protocol for the 29k) and the 88k bug monitor. It is now an
7164 integer specifying a debug level (normally 0 or 1, but 2 means more
7165 debugging info for the mips target).
7167 * DEC Alpha native support
7169 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
7170 debug info, but GDB works fairly well with the DEC compiler and should
7171 work with a future GCC release. See the README file for a few
7172 Alpha-specific notes.
7174 * Preliminary thread implementation
7176 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
7178 * LynxOS native and target support for 386
7180 This release has been hosted on LynxOS 2.2, and also can be configured
7181 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
7184 * Improvements in C++ mangling/demangling.
7186 This release has much better g++ debugging, specifically in name
7187 mangling/demangling, virtual function calls, print virtual table,
7188 call methods, ...etc.
7190 *** Changes in GDB-4.10:
7192 * User visible changes:
7194 Remote debugging using the GDB-specific (`target remote') protocol now
7195 supports the `load' command. This is only useful if you have some
7196 other way of getting the stub to the target system, and you can put it
7197 somewhere in memory where it won't get clobbered by the download.
7199 Filename completion now works.
7201 When run under emacs mode, the "info line" command now causes the
7202 arrow to point to the line specified. Also, "info line" prints
7203 addresses in symbolic form (as well as hex).
7205 All vxworks based targets now support a user settable option, called
7206 vxworks-timeout. This option represents the number of seconds gdb
7207 should wait for responses to rpc's. You might want to use this if
7208 your vxworks target is, perhaps, a slow software simulator or happens
7209 to be on the far side of a thin network line.
7213 This release contains support for using a DEC alpha as a GDB host for
7214 cross debugging. Native alpha debugging is not supported yet.
7217 *** Changes in GDB-4.9:
7221 This is the first GDB release which is accompanied by a matching testsuite.
7222 The testsuite requires installation of dejagnu, which should be available
7223 via ftp from most sites that carry GNU software.
7227 'Cfront' style demangling has had its name changed to 'ARM' style, to
7228 emphasize that it was written from the specifications in the C++ Annotated
7229 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
7230 disclaimers, it still generated too much confusion with users attempting to
7231 use gdb with AT&T cfront.
7235 GDB now uses a standard remote interface to a simulator library.
7236 So far, the library contains simulators for the Zilog Z8001/2, the
7237 Hitachi H8/300, H8/500 and Super-H.
7239 * New targets supported
7241 H8/300 simulator h8300-hitachi-hms or h8300hms
7242 H8/500 simulator h8500-hitachi-hms or h8500hms
7243 SH simulator sh-hitachi-hms or sh
7244 Z8000 simulator z8k-zilog-none or z8ksim
7245 IDT MIPS board over serial line mips-idt-ecoff
7247 Cross-debugging to GO32 targets is supported. It requires a custom
7248 version of the i386-stub.c module which is integrated with the
7249 GO32 memory extender.
7251 * New remote protocols
7253 MIPS remote debugging protocol.
7255 * New source languages supported
7257 This version includes preliminary support for Chill, a Pascal like language
7258 used by telecommunications companies. Chill support is also being integrated
7259 into the GNU compiler, but we don't know when it will be publically available.
7262 *** Changes in GDB-4.8:
7264 * HP Precision Architecture supported
7266 GDB now supports HP PA-RISC machines running HPUX. A preliminary
7267 version of this support was available as a set of patches from the
7268 University of Utah. GDB does not support debugging of programs
7269 compiled with the HP compiler, because HP will not document their file
7270 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
7271 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
7273 Many problems in the preliminary version have been fixed.
7275 * Faster and better demangling
7277 We have improved template demangling and fixed numerous bugs in the GNU style
7278 demangler. It can now handle type modifiers such as `static' or `const'. Wide
7279 character types (wchar_t) are now supported. Demangling of each symbol is now
7280 only done once, and is cached when the symbol table for a file is read in.
7281 This results in a small increase in memory usage for C programs, a moderate
7282 increase in memory usage for C++ programs, and a fantastic speedup in
7285 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
7286 from the specifications in the Annotated Reference Manual, which AT&T's
7287 compiler does not actually implement.
7289 * G++ multiple inheritance compiler problem
7291 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
7292 inheritance lattices was reworked to properly discover ambiguities. We
7293 recently found an example which causes this new algorithm to fail in a
7294 very subtle way, producing bad debug information for those classes.
7295 The file 'gcc.patch' (in this directory) can be applied to gcc to
7296 circumvent the problem. A future GCC release will contain a complete
7299 The previous G++ debug info problem (mentioned below for the gdb-4.7
7300 release) is fixed in gcc version 2.3.2.
7302 * Improved configure script
7304 The `configure' script will now attempt to guess your system type if
7305 you don't supply a host system type. The old scheme of supplying a
7306 host system triplet is preferable over using this. All the magic is
7307 done in the new `config.guess' script. Examine it for details.
7309 We have also brought our configure script much more in line with the FSF's
7310 version. It now supports the --with-xxx options. In particular,
7311 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
7312 The resulting GDB will not be able to read arbitrary object file formats --
7313 only the format ``expected'' to be used on the configured target system.
7314 We hope to make this the default in a future release.
7316 * Documentation improvements
7318 There's new internal documentation on how to modify GDB, and how to
7319 produce clean changes to the code. We implore people to read it
7320 before submitting changes.
7322 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
7323 M4 macros. The new texinfo.tex is provided in this release. Pre-built
7324 `info' files are also provided. To build `info' files from scratch,
7325 you will need the latest `makeinfo' release, which will be available in
7326 a future texinfo-X.Y release.
7328 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
7329 We're not sure exactly which versions have this problem, but it has
7330 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
7331 or better. If that isn't possible, there is a patch in
7332 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
7333 around this problem.
7337 GDB now supports array constants that can be used in expressions typed in by
7338 the user. The syntax is `{element, element, ...}'. Ie: you can now type
7339 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
7342 The new directory `gdb/sparclite' contains a program that demonstrates
7343 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
7345 * New native hosts supported
7347 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
7348 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
7350 * New targets supported
7352 AMD 29k family via UDI a29k-amd-udi or udi29k
7354 * New file formats supported
7356 BFD now supports reading HP/PA-RISC executables (SOM file format?),
7357 HPUX core files, and SCO 3.2v2 core files.
7361 Attaching to processes now works again; thanks for the many bug reports.
7363 We have also stomped on a bunch of core dumps caused by
7364 printf_filtered("%s") problems.
7366 We eliminated a copyright problem on the rpc and ptrace header files
7367 for VxWorks, which was discovered at the last minute during the 4.7
7368 release. You should now be able to build a VxWorks GDB.
7370 You can now interrupt gdb while an attached process is running. This
7371 will cause the attached process to stop, and give control back to GDB.
7373 We fixed problems caused by using too many file descriptors
7374 for reading symbols from object files and libraries. This was
7375 especially a problem for programs that used many (~100) shared
7378 The `step' command now only enters a subroutine if there is line number
7379 information for the subroutine. Otherwise it acts like the `next'
7380 command. Previously, `step' would enter subroutines if there was
7381 any debugging information about the routine. This avoids problems
7382 when using `cc -g1' on MIPS machines.
7384 * Internal improvements
7386 GDB's internal interfaces have been improved to make it easier to support
7387 debugging of multiple languages in the future.
7389 GDB now uses a common structure for symbol information internally.
7390 Minimal symbols (derived from linkage symbols in object files), partial
7391 symbols (from a quick scan of debug information), and full symbols
7392 contain a common subset of information, making it easier to write
7393 shared code that handles any of them.
7395 * New command line options
7397 We now accept --silent as an alias for --quiet.
7401 The memory-mapped-malloc library is now licensed under the GNU Library
7402 General Public License.
7404 *** Changes in GDB-4.7:
7406 * Host/native/target split
7408 GDB has had some major internal surgery to untangle the support for
7409 hosts and remote targets. Now, when you configure GDB for a remote
7410 target, it will no longer load in all of the support for debugging
7411 local programs on the host. When fully completed and tested, this will
7412 ensure that arbitrary host/target combinations are possible.
7414 The primary conceptual shift is to separate the non-portable code in
7415 GDB into three categories. Host specific code is required any time GDB
7416 is compiled on that host, regardless of the target. Target specific
7417 code relates to the peculiarities of the target, but can be compiled on
7418 any host. Native specific code is everything else: it can only be
7419 built when the host and target are the same system. Child process
7420 handling and core file support are two common `native' examples.
7422 GDB's use of /proc for controlling Unix child processes is now cleaner.
7423 It has been split out into a single module under the `target_ops' vector,
7424 plus two native-dependent functions for each system that uses /proc.
7426 * New hosts supported
7428 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
7429 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7430 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
7432 * New targets supported
7434 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
7435 68030 and CPU32 m68030-*-*, m68332-*-*
7437 * New native hosts supported
7439 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7440 (386bsd is not well tested yet)
7441 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
7443 * New file formats supported
7445 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
7446 supports reading of `a.out.adobe' object files, which are an a.out
7447 format extended with minimal information about multiple sections.
7451 `show copying' is the same as the old `info copying'.
7452 `show warranty' is the same as `info warrantee'.
7453 These were renamed for consistency. The old commands continue to work.
7455 `info handle' is a new alias for `info signals'.
7457 You can now define pre-command hooks, which attach arbitrary command
7458 scripts to any command. The commands in the hook will be executed
7459 prior to the user's command. You can also create a hook which will be
7460 executed whenever the program stops. See gdb.texinfo.
7464 We now deal with Cfront style name mangling, and can even extract type
7465 info from mangled symbols. GDB can automatically figure out which
7466 symbol mangling style your C++ compiler uses.
7468 Calling of methods and virtual functions has been improved as well.
7472 The crash that occurred when debugging Sun Ansi-C compiled binaries is
7473 fixed. This was due to mishandling of the extra N_SO stabs output
7476 We also finally got Ultrix 4.2 running in house, and fixed core file
7477 support, with help from a dozen people on the net.
7479 John M. Farrell discovered that the reason that single-stepping was so
7480 slow on all of the Mips based platforms (primarily SGI and DEC) was
7481 that we were trying to demangle and lookup a symbol used for internal
7482 purposes on every instruction that was being stepped through. Changing
7483 the name of that symbol so that it couldn't be mistaken for a C++
7484 mangled symbol sped things up a great deal.
7486 Rich Pixley sped up symbol lookups in general by getting much smarter
7487 about when C++ symbol mangling is necessary. This should make symbol
7488 completion (TAB on the command line) much faster. It's not as fast as
7489 we'd like, but it's significantly faster than gdb-4.6.
7493 A new user controllable variable 'call_scratch_address' can
7494 specify the location of a scratch area to be used when GDB
7495 calls a function in the target. This is necessary because the
7496 usual method of putting the scratch area on the stack does not work
7497 in systems that have separate instruction and data spaces.
7499 We integrated changes to support the 29k UDI (Universal Debugger
7500 Interface), but discovered at the last minute that we didn't have all
7501 of the appropriate copyright paperwork. We are working with AMD to
7502 resolve this, and hope to have it available soon.
7506 We have sped up the remote serial line protocol, especially for targets
7507 with lots of registers. It now supports a new `expedited status' ('T')
7508 message which can be used in place of the existing 'S' status message.
7509 This allows the remote stub to send only the registers that GDB
7510 needs to make a quick decision about single-stepping or conditional
7511 breakpoints, eliminating the need to fetch the entire register set for
7512 each instruction being stepped through.
7514 The GDB remote serial protocol now implements a write-through cache for
7515 registers, only re-reading the registers if the target has run.
7517 There is also a new remote serial stub for SPARC processors. You can
7518 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
7519 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
7520 processor with a serial port.
7524 Configure.in files have become much easier to read and modify. A new
7525 `table driven' format makes it more obvious what configurations are
7526 supported, and what files each one uses.
7530 There is a new opcodes library which will eventually contain all of the
7531 disassembly routines and opcode tables. At present, it only contains
7532 Sparc and Z8000 routines. This will allow the assembler, debugger, and
7533 disassembler (binutils/objdump) to share these routines.
7535 The libiberty library is now copylefted under the GNU Library General
7536 Public License. This allows more liberal use, and was done so libg++
7537 can use it. This makes no difference to GDB, since the Library License
7538 grants all the rights from the General Public License.
7542 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
7543 reference to the stabs symbol info used by the debugger. It is (as far
7544 as we know) the only published document on this fascinating topic. We
7545 encourage you to read it, compare it to the stabs information on your
7546 system, and send improvements on the document in general (to
7547 bug-gdb@prep.ai.mit.edu).
7549 And, of course, many bugs have been fixed.
7552 *** Changes in GDB-4.6:
7554 * Better support for C++ function names
7556 GDB now accepts as input the "demangled form" of C++ overloaded function
7557 names and member function names, and can do command completion on such names
7558 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
7559 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
7560 Make use of command completion, it is your friend.
7562 GDB also now accepts a variety of C++ mangled symbol formats. They are
7563 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
7564 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
7565 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
7566 for the list of formats.
7568 * G++ symbol mangling problem
7570 Recent versions of gcc have a bug in how they emit debugging information for
7571 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
7572 directory) can be applied to gcc to fix the problem. Alternatively, if you
7573 can't fix gcc, you can #define GCC_MANGLE_BUG when compiling gdb/symtab.c. The
7574 usual symptom is difficulty with setting breakpoints on methods. GDB complains
7575 about the method being non-existent. (We believe that version 2.2.2 of GCC has
7578 * New 'maintenance' command
7580 All of the commands related to hacking GDB internals have been moved out of
7581 the main command set, and now live behind the 'maintenance' command. This
7582 can also be abbreviated as 'mt'. The following changes were made:
7584 dump-me -> maintenance dump-me
7585 info all-breakpoints -> maintenance info breakpoints
7586 printmsyms -> maintenance print msyms
7587 printobjfiles -> maintenance print objfiles
7588 printpsyms -> maintenance print psymbols
7589 printsyms -> maintenance print symbols
7591 The following commands are new:
7593 maintenance demangle Call internal GDB demangler routine to
7594 demangle a C++ link name and prints the result.
7595 maintenance print type Print a type chain for a given symbol
7597 * Change to .gdbinit file processing
7599 We now read the $HOME/.gdbinit file before processing the argv arguments
7600 (e.g. reading symbol files or core files). This allows global parameters to
7601 be set, which will apply during the symbol reading. The ./.gdbinit is still
7602 read after argv processing.
7604 * New hosts supported
7606 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
7608 GNU/Linux support i386-unknown-linux or linux
7610 We are also including code to support the HP/PA running BSD and HPUX. This
7611 is almost guaranteed not to work, as we didn't have time to test or build it
7612 for this release. We are including it so that the more adventurous (or
7613 masochistic) of you can play with it. We also had major problems with the
7614 fact that the compiler that we got from HP doesn't support the -g option.
7617 * New targets supported
7619 Hitachi H8/300 h8300-hitachi-hms or h8300hms
7621 * More smarts about finding #include files
7623 GDB now remembers the compilation directory for all include files, and for
7624 all files from which C is generated (like yacc and lex sources). This
7625 greatly improves GDB's ability to find yacc/lex sources, and include files,
7626 especially if you are debugging your program from a directory different from
7627 the one that contains your sources.
7629 We also fixed a bug which caused difficulty with listing and setting
7630 breakpoints in include files which contain C code. (In the past, you had to
7631 try twice in order to list an include file that you hadn't looked at before.)
7633 * Interesting infernals change
7635 GDB now deals with arbitrary numbers of sections, where the symbols for each
7636 section must be relocated relative to that section's landing place in the
7637 target's address space. This work was needed to support ELF with embedded
7638 stabs used by Solaris-2.0.
7640 * Bug fixes (of course!)
7642 There have been loads of fixes for the following things:
7643 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
7644 i960, stabs, DOS(GO32), procfs, etc...
7646 See the ChangeLog for details.
7648 *** Changes in GDB-4.5:
7650 * New machines supported (host and target)
7652 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
7654 SGI Irix-4.x mips-sgi-irix4 or iris4
7656 * New malloc package
7658 GDB now uses a new memory manager called mmalloc, based on gmalloc.
7659 Mmalloc is capable of handling multiple heaps of memory. It is also
7660 capable of saving a heap to a file, and then mapping it back in later.
7661 This can be used to greatly speedup the startup of GDB by using a
7662 pre-parsed symbol table which lives in a mmalloc managed heap. For
7663 more details, please read mmalloc/mmalloc.texi.
7667 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
7668 'help info proc' for details.
7670 * MIPS ecoff symbol table format
7672 The code that reads MIPS symbol table format is now supported on all hosts.
7673 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
7676 * File name changes for MS-DOS
7678 Many files in the config directories have been renamed to make it easier to
7679 support GDB on MS-DOSe systems (which have very restrictive file name
7680 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
7681 environment) is close to working but has some remaining problems. Note
7682 that debugging of DOS programs is not supported, due to limitations
7683 in the ``operating system'', but it can be used to host cross-debugging.
7685 * Cross byte order fixes
7687 Many fixes have been made to support cross debugging of Sparc and MIPS
7688 targets from hosts whose byte order differs.
7690 * New -mapped and -readnow options
7692 If memory-mapped files are available on your system through the 'mmap'
7693 system call, you can use the -mapped option on the `file' or
7694 `symbol-file' commands to cause GDB to write the symbols from your
7695 program into a reusable file. If the program you are debugging is
7696 called `/path/fred', the mapped symbol file will be `./fred.syms'.
7697 Future GDB debugging sessions will notice the presence of this file,
7698 and will quickly map in symbol information from it, rather than reading
7699 the symbol table from the executable program. Using the '-mapped'
7700 option in a GDB `file' or `symbol-file' command has the same effect as
7701 starting GDB with the '-mapped' command-line option.
7703 You can cause GDB to read the entire symbol table immediately by using
7704 the '-readnow' option with any of the commands that load symbol table
7705 information (or on the GDB command line). This makes the command
7706 slower, but makes future operations faster.
7708 The -mapped and -readnow options are typically combined in order to
7709 build a `fred.syms' file that contains complete symbol information.
7710 A simple GDB invocation to do nothing but build a `.syms' file for future
7713 gdb -batch -nx -mapped -readnow programname
7715 The `.syms' file is specific to the host machine on which GDB is run.
7716 It holds an exact image of GDB's internal symbol table. It cannot be
7717 shared across multiple host platforms.
7719 * longjmp() handling
7721 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
7722 siglongjmp() without losing control. This feature has not yet been ported to
7723 all systems. It currently works on many 386 platforms, all MIPS-based
7724 platforms (SGI, DECstation, etc), and Sun3/4.
7728 Preliminary work has been put in to support the new Solaris OS from Sun. At
7729 this time, it can control and debug processes, but it is not capable of
7734 As always, many many bug fixes. The major areas were with g++, and mipsread.
7735 People using the MIPS-based platforms should experience fewer mysterious
7736 crashes and trashed symbol tables.
7738 *** Changes in GDB-4.4:
7740 * New machines supported (host and target)
7742 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7744 BSD Reno on Vax vax-dec-bsd
7745 Ultrix on Vax vax-dec-ultrix
7747 * New machines supported (target)
7749 AMD 29000 embedded, using EBMON a29k-none-none
7753 GDB continues to improve its handling of C++. `References' work better.
7754 The demangler has also been improved, and now deals with symbols mangled as
7755 per the Annotated C++ Reference Guide.
7757 GDB also now handles `stabs' symbol information embedded in MIPS
7758 `ecoff' symbol tables. Since the ecoff format was not easily
7759 extensible to handle new languages such as C++, this appeared to be a
7760 good way to put C++ debugging info into MIPS binaries. This option
7761 will be supported in the GNU C compiler, version 2, when it is
7764 * New features for SVR4
7766 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7767 shared libraries. Debugging dynamically linked programs should present
7768 only minor differences from debugging statically linked programs.
7770 The `info proc' command will print out information about any process
7771 on an SVR4 system (including the one you are debugging). At the moment,
7772 it prints the address mappings of the process.
7774 If you bring up GDB on another SVR4 system, please send mail to
7775 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7777 * Better dynamic linking support in SunOS
7779 Reading symbols from shared libraries which contain debugging symbols
7780 now works properly. However, there remain issues such as automatic
7781 skipping of `transfer vector' code during function calls, which
7782 make it harder to debug code in a shared library, than to debug the
7783 same code linked statically.
7787 GDB is now using the latest `getopt' routines from the FSF. This
7788 version accepts the -- prefix for options with long names. GDB will
7789 continue to accept the old forms (-option and +option) as well.
7790 Various single letter abbreviations for options have been explicity
7791 added to the option table so that they won't get overshadowed in the
7792 future by other options that begin with the same letter.
7796 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7797 Many assorted bugs have been handled. Many more remain to be handled.
7798 See the various ChangeLog files (primarily in gdb and bfd) for details.
7801 *** Changes in GDB-4.3:
7803 * New machines supported (host and target)
7805 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7806 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7807 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7809 * Almost SCO Unix support
7811 We had hoped to support:
7812 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7813 (except for core file support), but we discovered very late in the release
7814 that it has problems with process groups that render gdb unusable. Sorry
7815 about that. I encourage people to fix it and post the fixes.
7817 * Preliminary ELF and DWARF support
7819 GDB can read ELF object files on System V Release 4, and can handle
7820 debugging records for C, in DWARF format, in ELF files. This support
7821 is preliminary. If you bring up GDB on another SVR4 system, please
7822 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7827 GDB now uses the latest `readline' library. One user-visible change
7828 is that two tabs will list possible command completions, which previously
7829 required typing M-? (meta-question mark, or ESC ?).
7833 The `stepi' bug that many of you noticed has been squashed.
7834 Many bugs in C++ have been handled. Many more remain to be handled.
7835 See the various ChangeLog files (primarily in gdb and bfd) for details.
7837 * State of the MIPS world (in case you wondered):
7839 GDB can understand the symbol tables emitted by the compilers
7840 supplied by most vendors of MIPS-based machines, including DEC. These
7841 symbol tables are in a format that essentially nobody else uses.
7843 Some versions of gcc come with an assembler post-processor called
7844 mips-tfile. This program is required if you want to do source-level
7845 debugging of gcc-compiled programs. I believe FSF does not ship
7846 mips-tfile with gcc version 1, but it will eventually come with gcc
7849 Debugging of g++ output remains a problem. g++ version 1.xx does not
7850 really support it at all. (If you're lucky, you should be able to get
7851 line numbers and stack traces to work, but no parameters or local
7852 variables.) With some work it should be possible to improve the
7855 When gcc version 2 is released, you will have somewhat better luck.
7856 However, even then you will get confusing results for inheritance and
7859 We will eventually provide full debugging of g++ output on
7860 DECstations. This will probably involve some kind of stabs-in-ecoff
7861 encapulation, but the details have not been worked out yet.
7864 *** Changes in GDB-4.2:
7866 * Improved configuration
7868 Only one copy of `configure' exists now, and it is not self-modifying.
7869 Porting BFD is simpler.
7873 The `step' and `next' commands now only stop at the first instruction
7874 of a source line. This prevents the multiple stops that used to occur
7875 in switch statements, for-loops, etc. `Step' continues to stop if a
7876 function that has debugging information is called within the line.
7880 Lots of small bugs fixed. More remain.
7882 * New host supported (not target)
7884 Intel 386 PC clone running Mach i386-none-mach
7887 *** Changes in GDB-4.1:
7889 * Multiple source language support
7891 GDB now has internal scaffolding to handle several source languages.
7892 It determines the type of each source file from its filename extension,
7893 and will switch expression parsing and number formatting to match the
7894 language of the function in the currently selected stack frame.
7895 You can also specifically set the language to be used, with
7896 `set language c' or `set language modula-2'.
7900 GDB now has preliminary support for the GNU Modula-2 compiler,
7901 currently under development at the State University of New York at
7902 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7903 continue through the fall of 1991 and into 1992.
7905 Other Modula-2 compilers are currently not supported, and attempting to
7906 debug programs compiled with them will likely result in an error as the
7907 symbol table is read. Feel free to work on it, though!
7909 There are hooks in GDB for strict type checking and range checking,
7910 in the `Modula-2 philosophy', but they do not currently work.
7914 GDB can now write to executable and core files (e.g. patch
7915 a variable's value). You must turn this switch on, specify
7916 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7917 by assigning a new value to a variable. Modifications take
7920 * Automatic SunOS shared library reading
7922 When you run your program, GDB automatically determines where its
7923 shared libraries (if any) have been loaded, and reads their symbols.
7924 The `share' command is no longer needed. This also works when
7925 examining core files.
7929 You can specify the number of lines that the `list' command shows.
7932 * New machines supported (host and target)
7934 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7935 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7936 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7938 * New hosts supported (not targets)
7940 IBM RT/PC: romp-ibm-aix or rtpc
7942 * New targets supported (not hosts)
7944 AMD 29000 embedded with COFF a29k-none-coff
7945 AMD 29000 embedded with a.out a29k-none-aout
7946 Ultracomputer remote kernel debug a29k-nyu-kern
7948 * New remote interfaces
7954 *** Changes in GDB-4.0:
7958 Wide output is wrapped at good places to make the output more readable.
7960 Gdb now supports cross-debugging from a host machine of one type to a
7961 target machine of another type. Communication with the target system
7962 is over serial lines. The ``target'' command handles connecting to the
7963 remote system; the ``load'' command will download a program into the
7964 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7965 also supports debugging of realtime processes running under VxWorks,
7966 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7967 stub on the target system.
7969 New CPUs supported include the AMD 29000 and Intel 960.
7971 GDB now reads object files and symbol tables via a ``binary file''
7972 library, which allows a single copy of GDB to debug programs of multiple
7973 object file types such as a.out and coff.
7975 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7976 refcard.dvi and refcard.ps are available to format it).
7979 * Control-Variable user interface simplified
7981 All variables that control the operation of the debugger can be set
7982 by the ``set'' command, and displayed by the ``show'' command.
7984 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7985 ``Show prompt'' produces the response:
7986 Gdb's prompt is new-gdb=>.
7988 What follows are the NEW set commands. The command ``help set'' will
7989 print a complete list of old and new set commands. ``help set FOO''
7990 will give a longer description of the variable FOO. ``show'' will show
7991 all of the variable descriptions and their current settings.
7993 confirm on/off: Enables warning questions for operations that are
7994 hard to recover from, e.g. rerunning the program while
7995 it is already running. Default is ON.
7997 editing on/off: Enables EMACS style command line editing
7998 of input. Previous lines can be recalled with
7999 control-P, the current line can be edited with control-B,
8000 you can search for commands with control-R, etc.
8003 history filename NAME: NAME is where the gdb command history
8004 will be stored. The default is .gdb_history,
8005 or the value of the environment variable
8008 history size N: The size, in commands, of the command history. The
8009 default is 256, or the value of the environment variable
8012 history save on/off: If this value is set to ON, the history file will
8013 be saved after exiting gdb. If set to OFF, the
8014 file will not be saved. The default is OFF.
8016 history expansion on/off: If this value is set to ON, then csh-like
8017 history expansion will be performed on
8018 command line input. The default is OFF.
8020 radix N: Sets the default radix for input and output. It can be set
8021 to 8, 10, or 16. Note that the argument to "radix" is interpreted
8022 in the current radix, so "set radix 10" is always a no-op.
8024 height N: This integer value is the number of lines on a page. Default
8025 is 24, the current `stty rows'' setting, or the ``li#''
8026 setting from the termcap entry matching the environment
8029 width N: This integer value is the number of characters on a line.
8030 Default is 80, the current `stty cols'' setting, or the ``co#''
8031 setting from the termcap entry matching the environment
8034 Note: ``set screensize'' is obsolete. Use ``set height'' and
8035 ``set width'' instead.
8037 print address on/off: Print memory addresses in various command displays,
8038 such as stack traces and structure values. Gdb looks
8039 more ``symbolic'' if you turn this off; it looks more
8040 ``machine level'' with it on. Default is ON.
8042 print array on/off: Prettyprint arrays. New convenient format! Default
8045 print demangle on/off: Print C++ symbols in "source" form if on,
8048 print asm-demangle on/off: Same, for assembler level printouts
8051 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
8054 * Support for Epoch Environment.
8056 The epoch environment is a version of Emacs v18 with windowing. One
8057 new command, ``inspect'', is identical to ``print'', except that if you
8058 are running in the epoch environment, the value is printed in its own
8062 * Support for Shared Libraries
8064 GDB can now debug programs and core files that use SunOS shared libraries.
8065 Symbols from a shared library cannot be referenced
8066 before the shared library has been linked with the program (this
8067 happens after you type ``run'' and before the function main() is entered).
8068 At any time after this linking (including when examining core files
8069 from dynamically linked programs), gdb reads the symbols from each
8070 shared library when you type the ``sharedlibrary'' command.
8071 It can be abbreviated ``share''.
8073 sharedlibrary REGEXP: Load shared object library symbols for files
8074 matching a unix regular expression. No argument
8075 indicates to load symbols for all shared libraries.
8077 info sharedlibrary: Status of loaded shared libraries.
8082 A watchpoint stops execution of a program whenever the value of an
8083 expression changes. Checking for this slows down execution
8084 tremendously whenever you are in the scope of the expression, but is
8085 quite useful for catching tough ``bit-spreader'' or pointer misuse
8086 problems. Some machines such as the 386 have hardware for doing this
8087 more quickly, and future versions of gdb will use this hardware.
8089 watch EXP: Set a watchpoint (breakpoint) for an expression.
8091 info watchpoints: Information about your watchpoints.
8093 delete N: Deletes watchpoint number N (same as breakpoints).
8094 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
8095 enable N: Re-enables watchpoint number N (same as breakpoints).
8098 * C++ multiple inheritance
8100 When used with a GCC version 2 compiler, GDB supports multiple inheritance
8103 * C++ exception handling
8105 Gdb now supports limited C++ exception handling. Besides the existing
8106 ability to breakpoint on an exception handler, gdb can breakpoint on
8107 the raising of an exception (before the stack is peeled back to the
8110 catch FOO: If there is a FOO exception handler in the dynamic scope,
8111 set a breakpoint to catch exceptions which may be raised there.
8112 Multiple exceptions (``catch foo bar baz'') may be caught.
8114 info catch: Lists all exceptions which may be caught in the
8115 current stack frame.
8118 * Minor command changes
8120 The command ``call func (arg, arg, ...)'' now acts like the print
8121 command, except it does not print or save a value if the function's result
8122 is void. This is similar to dbx usage.
8124 The ``up'' and ``down'' commands now always print the frame they end up
8125 at; ``up-silently'' and `down-silently'' can be used in scripts to change
8126 frames without printing.
8128 * New directory command
8130 'dir' now adds directories to the FRONT of the source search path.
8131 The path starts off empty. Source files that contain debug information
8132 about the directory in which they were compiled can be found even
8133 with an empty path; Sun CC and GCC include this information. If GDB can't
8134 find your source file in the current directory, type "dir .".
8136 * Configuring GDB for compilation
8138 For normal use, type ``./configure host''. See README or gdb.texinfo
8141 GDB now handles cross debugging. If you are remotely debugging between
8142 two different machines, type ``./configure host -target=targ''.
8143 Host is the machine where GDB will run; targ is the machine
8144 where the program that you are debugging will run.