1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 9
6 * Help and apropos commands will now show the documentation of a
7 command only once, even if that command has one or more aliases.
8 These commands now show the command name, then all of its aliases,
9 and finally the description of the command.
11 * 'help aliases' now shows only the user defined aliases. GDB predefined
12 aliases are shown together with their aliased command.
14 * GDB now supports debuginfod, an HTTP server for distributing ELF/DWARF
15 debugging information as well as source code.
17 When built with debuginfod, GDB can automatically query debuginfod
18 servers for the separate debug files and source code of the executable
21 To build GDB with debuginfod, pass --with-debuginfod to configure (this
22 requires libdebuginfod, the debuginfod client library).
24 debuginfod is distributed with elfutils, starting with version 0.178.
26 You can get the latest version from https://sourceware.org/elfutils.
28 * New features in the GDB remote stub, GDBserver
30 ** GDBserver is now supported on RISC-V GNU/Linux.
32 ** GDBserver no longer supports these host triplets:
43 i[34567]86-*-mingw32ce*
45 * Debugging MS-Windows processes now sets $_exitsignal when the
46 inferior is terminated by a signal, instead of setting $_exitcode.
48 * Multithreaded symbol loading has now been enabled by default on systems
49 that support it (see entry for GDB 9, below), providing faster
50 performance for programs with many symbols.
52 * The $_siginfo convenience variable now also works on Windows targets,
53 and will display the EXCEPTION_RECORD of the last handled exception.
55 * TUI windows can now be arranged horizontally.
57 * The command history filename can now be set to the empty string
58 either using 'set history filename' or by setting 'GDBHISTFILE=' in
59 the environment. The effect of setting this filename to the empty
60 string is that GDB will not try to load any previous command
63 * On Windows targets, it is now possible to debug 32-bit programs with a
68 set exec-file-mismatch -- Set exec-file-mismatch handling (ask|warn|off).
69 show exec-file-mismatch -- Show exec-file-mismatch handling (ask|warn|off).
70 Set or show the option 'exec-file-mismatch'. When GDB attaches to a
71 running process, this new option indicates whether to detect
72 a mismatch between the current executable file loaded by GDB and the
73 executable file used to start the process. If 'ask', the default,
74 display a warning and ask the user whether to load the process
75 executable file; if 'warn', just display a warning; if 'off', don't
76 attempt to detect a mismatch.
78 tui new-layout NAME WINDOW WEIGHT [WINDOW WEIGHT]...
79 Define a new TUI layout, specifying its name and the windows that
82 maintenance print xml-tdesc [FILE]
83 Prints the current target description as an XML document. If the
84 optional FILE is provided (which is an XML target description) then
85 the target description is read from FILE into GDB, and then
90 alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
91 The alias command can now specify default args for an alias.
92 GDB automatically prepends the alias default args to the argument list
93 provided explicitly by the user.
94 For example, to have a backtrace with full details, you can define
96 'alias bt_ALL = backtrace -entry-values both -frame-arg all
97 -past-main -past-entry -full'.
98 Alias default arguments can also use a set of nested 'with' commands,
99 e.g. 'alias pp10 = with print pretty -- with print elem 10 -- print'
100 defines the alias pp10 that will pretty print a maximum of 10 elements
101 of the given expression (if the expression is an array).
105 GNU/Linux/RISC-V (gdbserver) riscv*-*-linux*
109 ** gdb.register_window_type can be used to implement new TUI windows
112 ** Dynamic types can now be queried. gdb.Type has a new attribute,
113 "dynamic", and gdb.Type.sizeof can be None for a dynamic type. A
114 field of a dynamic type may have None for its "bitpos" attribute
117 ** Commands written in Python can be in the "TUI" help class by
118 registering with the new constant gdb.COMMAND_TUI.
122 * 'thread-exited' event is now available in the annotations interface.
124 * New built-in convenience variables $_gdb_major and $_gdb_minor
125 provide the GDB version. They are handy for conditionally using
126 features available only in or since specific GDB versions, in
127 scripts that should work error-free with many different versions,
128 such as in system-wide init files.
130 * New built-in convenience functions $_gdb_setting, $_gdb_setting_str,
131 $_gdb_maint_setting and $_gdb_maint_setting_str provide access to values
132 of the GDB settings and the GDB maintenance settings. They are handy
133 for changing the logic of user defined commands depending on the
134 current GDB settings.
136 * GDB now supports Thread Local Storage (TLS) variables on several
137 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
138 architectures require kernel changes. TLS is not yet supported for
139 amd64 and i386 process core dumps.
141 * Support for Pointer Authentication (PAC) on AArch64 Linux. Return
142 addresses that required unmasking are shown in the backtrace with the
145 * Two new convenience functions $_cimag and $_creal that extract the
146 imaginary and real parts respectively from complex numbers.
148 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
149 provide the exitcode or exit status of the shell commands launched by
150 GDB commands such as "shell", "pipe" and "make".
152 * The command define-prefix can now define user defined prefix commands.
153 User defined commands can now be defined using these user defined prefix
156 * Command names can now use the . character.
158 * The RX port now supports XML target descriptions.
160 * GDB now shows the Ada task names at more places, e.g. in task switching
163 * GDB can now be compiled with Python 3 on Windows.
165 * New convenience variable $_ada_exception holds the address of the
166 Ada exception being thrown. This is set by Ada-related catchpoints.
168 * GDB can now place breakpoints on nested functions and subroutines in
169 Fortran code. The '::' operator can be used between parent and
170 child scopes when placing breakpoints, for example:
172 (gdb) break outer_function::inner_function
174 The 'outer_function::' prefix is only needed if 'inner_function' is
175 not visible in the current scope.
177 * In addition to the system-wide gdbinit file, if configured with
178 --with-system-gdbinit-dir, GDB will now also load files in that directory
179 as system gdbinit files, unless the -nx or -n flag is provided. Files
180 with extensions .gdb, .py and .scm are supported as long as GDB was
181 compiled with support for that language.
183 * GDB now supports multithreaded symbol loading for higher performance.
184 This feature is still in testing, so it is disabled by default. You
185 can turn it on using 'maint set worker-threads unlimited'.
187 * Multi-target debugging support
189 GDB now supports debugging multiple target connections
190 simultaneously. For example, you can now have each inferior
191 connected to different remote servers running in different machines,
192 or have one inferior debugging a local native process, an inferior
193 debugging a core dump, etc.
195 This support is experimental and comes with some limitations -- you
196 can only resume multiple targets simultaneously if all targets
197 support non-stop mode, and all remote stubs or servers must support
198 the same set of remote protocol features exactly. See also "info
199 connections" and "add-inferior -no-connection" below, and "maint set
200 target-non-stop" in the user manual.
204 ** The gdb.Value type has a new method 'format_string' which returns a
205 string representing the value. The formatting is controlled by the
206 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
207 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
208 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
210 ** gdb.Type has a new property 'objfile' which returns the objfile the
213 ** The frame information printed by the python frame filtering code
214 is now consistent with what the 'backtrace' command prints when
215 there are no filters, or when the 'backtrace' '-no-filters' option
218 ** The new function gdb.lookup_static_symbol can be used to look up
219 symbols with static linkage.
221 ** The new function gdb.lookup_static_symbols can be used to look up
222 all static symbols with static linkage.
224 ** gdb.Objfile has new methods 'lookup_global_symbol' and
225 'lookup_static_symbol' to lookup a symbol from this objfile only.
227 ** gdb.Block now supports the dictionary syntax for accessing symbols in
228 this block (e.g. block['local_variable']).
232 | [COMMAND] | SHELL_COMMAND
233 | -d DELIM COMMAND DELIM SHELL_COMMAND
234 pipe [COMMAND] | SHELL_COMMAND
235 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
236 Executes COMMAND and sends its output to SHELL_COMMAND.
237 With no COMMAND, repeat the last executed command
238 and send its output to SHELL_COMMAND.
240 define-prefix COMMAND
241 Define or mark a command as a user-defined prefix command.
243 with SETTING [VALUE] [-- COMMAND]
244 w SETTING [VALUE] [-- COMMAND]
245 Temporarily set SETTING, run COMMAND, and restore SETTING.
246 Usage: with SETTING -- COMMAND
247 With no COMMAND, repeats the last executed command.
248 SETTING is any GDB setting you can change with the "set"
249 subcommands. For example, 'with language c -- print someobj'
250 temporarily switches to the C language in order to print someobj.
251 Settings can be combined: 'w lang c -- w print elements unlimited --
252 usercmd' switches to the C language and runs usercmd with no limit
253 of array elements to print.
255 maint with SETTING [VALUE] [-- COMMAND]
256 Like "with", but works with "maintenance set" settings.
258 set may-call-functions [on|off]
259 show may-call-functions
260 This controls whether GDB will attempt to call functions in
261 the program, such as with expressions in the print command. It
262 defaults to on. Calling functions in the program being debugged
263 can have undesired side effects. It is now possible to forbid
264 such function calls. If function calls are forbidden, GDB will throw
265 an error when a command (such as print expression) calls a function
268 set print finish [on|off]
270 This controls whether the `finish' command will display the value
271 that is returned by the current function. When `off', the value is
272 still entered into the value history, but it is not printed. The
277 Allows deeply nested structures to be simplified when printing by
278 replacing deeply nested parts (beyond the max-depth) with ellipses.
279 The default max-depth is 20, but this can be set to unlimited to get
280 the old behavior back.
282 set print raw-values [on|off]
283 show print raw-values
284 By default, GDB applies the enabled pretty printers when printing a
285 value. This allows to ignore the enabled pretty printers for a series
286 of commands. The default is 'off'.
288 set logging debugredirect [on|off]
289 By default, GDB debug output will go to both the terminal and the logfile.
290 Set if you want debug output to go only to the log file.
292 set style title foreground COLOR
293 set style title background COLOR
294 set style title intensity VALUE
295 Control the styling of titles.
297 set style highlight foreground COLOR
298 set style highlight background COLOR
299 set style highlight intensity VALUE
300 Control the styling of highlightings.
302 maint set worker-threads
303 maint show worker-threads
304 Control the number of worker threads that can be used by GDB. The
305 default is 0. "unlimited" lets GDB choose a number that is
306 reasonable. Currently worker threads are only used when demangling
307 the names of linker symbols.
309 set style tui-border foreground COLOR
310 set style tui-border background COLOR
311 Control the styling of TUI borders.
313 set style tui-active-border foreground COLOR
314 set style tui-active-border background COLOR
315 Control the styling of the active TUI border.
317 maint set test-settings KIND
318 maint show test-settings KIND
319 A set of commands used by the testsuite for exercising the settings
322 maint set tui-resize-message [on|off]
323 maint show tui-resize-message
324 Control whether GDB prints a message each time the terminal is
325 resized when in TUI mode. This is primarily useful for testing the
328 set print frame-info [short-location|location|location-and-address
329 |source-and-location|source-line|auto]
330 show print frame-info
331 This controls what frame information is printed by the commands printing
332 a frame. This setting will e.g. influence the behaviour of 'backtrace',
333 'frame', 'stepi'. The python frame filtering also respect this setting.
334 The 'backtrace' '-frame-info' option can override this global setting.
336 set tui compact-source
337 show tui compact-source
339 Enable the "compact" display mode for the TUI source window. The
340 compact display uses only as much space as is needed for the line
341 numbers in the current file, and only a single space to separate the
342 line numbers from the source.
344 info modules [-q] [REGEXP]
345 Return a list of Fortran modules matching REGEXP, or all modules if
348 info module functions [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
349 Return a list of functions within all modules, grouped by module.
350 The list of functions can be restricted with the optional regular
351 expressions. MODULE_REGEXP matches against the module name,
352 TYPE_REGEXP matches against the function type signature, and REGEXP
353 matches against the function name.
355 info module variables [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
356 Return a list of variables within all modules, grouped by module.
357 The list of variables can be restricted with the optional regular
358 expressions. MODULE_REGEXP matches against the module name,
359 TYPE_REGEXP matches against the variable type, and REGEXP matches
360 against the variable name.
362 set debug remote-packet-max-chars
363 show debug remote-packet-max-chars
364 Controls the number of characters to output in a remote packet when using
366 The default is 512 bytes.
369 Lists the target connections currently in use.
374 The "help" command uses the title style to enhance the
375 readibility of its output by styling the classes and
379 Similarly to "help", the "apropos" command also uses the
380 title style for the command names. "apropos" accepts now
381 a flag "-v" (verbose) to show the full documentation
382 of matching commands and to use the highlight style to mark
383 the documentation parts matching REGEXP.
387 The GDB printf and eval commands can now print C-style and Ada-style
388 string convenience variables without calling functions in the program.
389 This allows to do formatted printing of strings without having
390 a running inferior, or when debugging a core dump.
392 info sources [-dirname | -basename] [--] [REGEXP]
393 This command has now optional arguments to only print the files
394 whose names match REGEXP. The arguments -dirname and -basename
395 allow to restrict matching respectively to the dirname and basename
399 The "show style" and its subcommands are now styling
400 a style name in their output using its own style, to help
401 the user visualize the different styles.
403 set print frame-arguments
404 The new value 'presence' indicates to only indicate the presence of
405 arguments using ..., instead of printing argument names and values.
407 set print raw-frame-arguments
408 show print raw-frame-arguments
410 These commands replace the similarly-named "set/show print raw
411 frame-arguments" commands (now with a dash instead of a space). The
412 old commands are now deprecated and may be removed in a future
415 add-inferior [-no-connection]
416 The add-inferior command now supports a "-no-connection" flag that
417 makes the new inferior start with no target connection associated.
418 By default, the new inferior inherits the target connection of the
419 current inferior. See also "info connections".
422 This command's output now includes a new "Connection" column
423 indicating which target connection an inferior is bound to. See
424 "info connections" above.
426 maint test-options require-delimiter
427 maint test-options unknown-is-error
428 maint test-options unknown-is-operand
429 maint show test-options-completion-result
430 Commands used by the testsuite to validate the command options
433 focus, winheight, +, -, >, <
434 These commands are now case-sensitive.
436 * New command options, command completion
438 GDB now has a standard infrastructure to support dash-style command
439 options ('-OPT'). One benefit is that commands that use it can
440 easily support completion of command line arguments. Try "CMD
441 -[TAB]" or "help CMD" to find options supported by a command. Over
442 time, we intend to migrate most commands to this infrastructure. A
443 number of commands got support for new command options in this
446 ** The "print" and "compile print" commands now support a number of
447 options that allow overriding relevant global print settings as
448 set by "set print" subcommands:
452 -array-indexes [on|off]
453 -elements NUMBER|unlimited
458 -repeats NUMBER|unlimited
459 -static-members [on|off]
464 Note that because the "print"/"compile print" commands accept
465 arbitrary expressions which may look like options (including
466 abbreviations), if you specify any command option, then you must
467 use a double dash ("--") to mark the end of argument processing.
469 ** The "backtrace" command now supports a number of options that
470 allow overriding relevant global print settings as set by "set
471 backtrace" and "set print" subcommands:
473 -entry-values no|only|preferred|if-needed|both|compact|default
474 -frame-arguments all|scalars|none
475 -raw-frame-arguments [on|off]
476 -frame-info auto|source-line|location|source-and-location
477 |location-and-address|short-location
481 In addition, the full/no-filters/hide qualifiers are now also
482 exposed as command options too:
488 ** The "frame apply", "tfaas" and "faas" commands similarly now
489 support the following options:
494 ** The new "info sources" options -dirname and -basename options
495 are using the standard '-OPT' infrastructure.
497 All options above can also be abbreviated. The argument of boolean
498 (on/off) options can be 0/1 too, and also the argument is assumed
499 "on" if omitted. This allows writing compact command invocations,
502 (gdb) p -ra -p -o 0 -- *myptr
504 The above is equivalent to:
506 (gdb) print -raw-values -pretty -object off -- *myptr
508 ** The "info types" command now supports the '-q' flag to disable
509 printing of some header information in a similar fashion to "info
510 variables" and "info functions".
512 ** The "info variables", "info functions", and "whereis" commands
513 now take a '-n' flag that excludes non-debug symbols (symbols
514 from the symbol table, not from the debug info such as DWARF)
517 * Completion improvements
519 ** GDB can now complete the options of the "thread apply all" and
520 "taas" commands, and their "-ascending" option can now be
523 ** GDB can now complete the options of the "info threads", "info
524 functions", "info variables", "info locals", and "info args"
527 ** GDB can now complete the options of the "compile file" and
528 "compile code" commands. The "compile file" command now
529 completes on filenames.
531 ** GDB can now complete the backtrace command's
532 "full/no-filters/hide" qualifiers.
534 * In settings, you can now abbreviate "unlimited".
536 E.g., "set print elements u" is now equivalent to "set print
542 This lists all the possible completions for the rest of the line, if it
543 were to be given as a command itself. This is intended for use by MI
544 frontends in cases when separate CLI and MI channels cannot be used.
546 -catch-throw, -catch-rethrow, and -catch-catch
547 These can be used to catch C++ exceptions in a similar fashion to
548 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
550 -symbol-info-functions, -symbol-info-types, and -symbol-info-variables
551 These commands are the MI equivalent of the CLI commands 'info
552 functions', 'info types', and 'info variables' respectively.
554 -symbol-info-modules, this is the MI equivalent of the CLI 'info
557 -symbol-info-module-functions and -symbol-info-module-variables.
558 These commands are the MI equivalent of the CLI commands 'info
559 module functions' and 'info module variables'.
563 ** The default version of the MI interpreter is now 3 (-i=mi3).
565 ** The output of information about multi-location breakpoints (which is
566 syntactically incorrect in MI 2) has changed in MI 3. This affects
567 the following commands and events:
571 - =breakpoint-created
572 - =breakpoint-modified
574 The -fix-multi-location-breakpoint-output command can be used to enable
575 this behavior with previous MI versions.
577 ** Backtraces and frames include a new optional field addr_flags which is
578 given after the addr field. On AArch64 this contains PAC if the address
579 has been masked in the frame. On all other targets the field is not
584 The testsuite now creates the files gdb.cmd (containing the arguments
585 used to launch GDB) and gdb.in (containing all the commands sent to
586 GDB) in the output directory for each test script. Multiple invocations
587 are appended with .1, .2, .3 etc.
589 * Building GDB and GDBserver now requires GNU make >= 3.82.
591 Using another implementation of the make program or an earlier version of
592 GNU make to build GDB or GDBserver is not supported.
594 * Building GDB now requires GNU readline >= 7.0.
596 GDB now bundles GNU readline 8.0, but if you choose to use
597 --with-system-readline, only readline >= 7.0 can be used.
599 * The TUI SingleKey keymap is now named "SingleKey". This can be used
600 from .inputrc to bind keys in this keymap. This feature is only
601 available when gdb is built against GNU readline 8.0 or later.
603 * Removed targets and native configurations
605 GDB no longer supports debugging the Cell Broadband Engine. This includes
606 both debugging standalone Cell/B.E. SPU applications and integrated debugging
607 of Cell/B.E. applications that use both the PPU and SPU architectures.
613 * Removed targets and native configurations
615 Solaris 10 i?86-*-solaris2.10, x86_64-*-solaris2.10,
618 *** Changes in GDB 8.3
620 * GDB and GDBserver now support access to additional registers on
621 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
624 * GDB now has experimental support for the compilation and injection of
625 C++ source code into the inferior. This beta release does not include
626 support for several language features, such as templates, constructors,
629 This feature requires GCC 7.1 or higher built with libcp1.so
632 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
633 can be passed using the '[ADDRESS]:PORT' notation, or the regular
634 'ADDRESS:PORT' method.
636 * DWARF index cache: GDB can now automatically save indices of DWARF
637 symbols on disk to speed up further loading of the same binaries.
639 * Ada task switching is now supported on aarch64-elf targets when
640 debugging a program using the Ravenscar Profile. For more information,
641 see the "Tasking Support when using the Ravenscar Profile" section
642 in the GDB user manual.
644 * GDB in batch mode now exits with status 1 if the last command to be
647 * The RISC-V target now supports target descriptions.
649 * System call catchpoints now support system call aliases on FreeBSD.
650 When the ABI of a system call changes in FreeBSD, this is
651 implemented by leaving a compatibility system call using the old ABI
652 at the existing number and allocating a new system call number for
653 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
654 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
655 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
656 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
657 so that a system call catchpoint for the 'kevent' system call will
658 catch invocations of both the 'kevent' and 'freebsd11_kevent'
659 binaries. This ensures that 'kevent' system calls are caught for
660 binaries using either the old or new ABIs.
662 * Terminal styling is now available for the CLI and the TUI. GNU
663 Source Highlight can additionally be used to provide styling of
664 source code snippets. See the "set style" commands, below, for more
667 * Removed support for old demangling styles arm, edg, gnu, hp and
672 set debug compile-cplus-types
673 show debug compile-cplus-types
674 Control the display of debug output about type conversion in the
675 C++ compile feature. Commands have no effect while compiling
680 Control whether debug output about files/functions skipping is
683 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
684 Apply a command to some frames.
685 FLAG arguments allow to control what output to produce and how to handle
686 errors raised when applying COMMAND to a frame.
689 Apply a command to all threads (ignoring errors and empty output).
690 Shortcut for 'thread apply all -s COMMAND'.
693 Apply a command to all frames (ignoring errors and empty output).
694 Shortcut for 'frame apply all -s COMMAND'.
697 Apply a command to all frames of all threads (ignoring errors and empty
699 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
701 maint set dwarf unwinders (on|off)
702 maint show dwarf unwinders
703 Control whether DWARF unwinders can be used.
706 Display a list of open files for a process.
710 Changes to the "frame", "select-frame", and "info frame" CLI commands.
711 These commands all now take a frame specification which
712 is either a frame level, or one of the keywords 'level', 'address',
713 'function', or 'view' followed by a parameter. Selecting a frame by
714 address, or viewing a frame outside the current backtrace now
715 requires the use of a keyword. Selecting a frame by level is
716 unchanged. The MI comment "-stack-select-frame" is unchanged.
718 target remote FILENAME
719 target extended-remote FILENAME
720 If FILENAME is a Unix domain socket, GDB will attempt to connect
721 to this socket instead of opening FILENAME as a character device.
723 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
724 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
725 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
726 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
727 These commands can now print only the searched entities
728 matching the provided regexp(s), giving a condition
729 on the entity names or entity types. The flag -q disables
730 printing headers or informations messages.
736 These commands now determine the syntax for the shown entities
737 according to the language chosen by `set language'. In particular,
738 `set language auto' means to automatically choose the language of
741 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
742 The 'thread apply' command accepts new FLAG arguments.
743 FLAG arguments allow to control what output to produce and how to handle
744 errors raised when applying COMMAND to a thread.
746 set tui tab-width NCHARS
747 show tui tab-width NCHARS
748 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
750 set style enabled [on|off]
752 Enable or disable terminal styling. Styling is enabled by default
753 on most hosts, but disabled by default when in batch mode.
755 set style sources [on|off]
757 Enable or disable source code styling. Source code styling is
758 enabled by default, but only takes effect if styling in general is
759 enabled, and if GDB was linked with GNU Source Highlight.
761 set style filename foreground COLOR
762 set style filename background COLOR
763 set style filename intensity VALUE
764 Control the styling of file names.
766 set style function foreground COLOR
767 set style function background COLOR
768 set style function intensity VALUE
769 Control the styling of function names.
771 set style variable foreground COLOR
772 set style variable background COLOR
773 set style variable intensity VALUE
774 Control the styling of variable names.
776 set style address foreground COLOR
777 set style address background COLOR
778 set style address intensity VALUE
779 Control the styling of addresses.
783 ** The '-data-disassemble' MI command now accepts an '-a' option to
784 disassemble the whole function surrounding the given program
785 counter value or function name. Support for this feature can be
786 verified by using the "-list-features" command, which should
787 contain "data-disassemble-a-option".
789 ** Command responses and notifications that include a frame now include
790 the frame's architecture in a new "arch" attribute.
792 * New native configurations
794 GNU/Linux/RISC-V riscv*-*-linux*
795 FreeBSD/riscv riscv*-*-freebsd*
799 GNU/Linux/RISC-V riscv*-*-linux*
801 CSKY GNU/LINUX csky*-*-linux
802 FreeBSD/riscv riscv*-*-freebsd*
804 GNU/Linux/OpenRISC or1k*-*-linux*
808 GDB no longer supports native debugging on versions of MS-Windows
813 ** GDB no longer supports Python versions less than 2.6.
815 ** The gdb.Inferior type has a new 'progspace' property, which is the program
816 space associated to that inferior.
818 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
819 of objfiles associated to that program space.
821 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
822 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
825 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
826 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
827 correct and did not work properly.
829 ** The gdb.Value type has a new constructor, which is used to construct a
830 gdb.Value from a Python buffer object and a gdb.Type.
836 Enable or disable the undefined behavior sanitizer. This is
837 disabled by default, but passing --enable-ubsan=yes or
838 --enable-ubsan=auto to configure will enable it. Enabling this can
839 cause a performance penalty. The undefined behavior sanitizer was
840 first introduced in GCC 4.9.
842 *** Changes in GDB 8.2
844 * The 'set disassembler-options' command now supports specifying options
847 * The 'symbol-file' command now accepts an '-o' option to add a relative
848 offset to all sections.
850 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
851 a relative offset to all sections, but it allows to override the load
852 address of individual sections using '-s'.
854 * The 'add-symbol-file' command no longer requires the second argument
855 (address of the text section).
857 * The endianness used with the 'set endian auto' mode in the absence of
858 an executable selected for debugging is now the last endianness chosen
859 either by one of the 'set endian big' and 'set endian little' commands
860 or by inferring from the last executable used, rather than the startup
863 * The pager now allows a "c" response, meaning to disable the pager
864 for the rest of the current command.
866 * The commands 'info variables/functions/types' now show the source line
867 numbers of symbol definitions when available.
869 * 'info proc' now works on running processes on FreeBSD systems and core
870 files created on FreeBSD systems.
872 * C expressions can now use _Alignof, and C++ expressions can now use
875 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
876 the vector length while the process is running.
882 Control display of debugging info regarding the FreeBSD native target.
884 set|show varsize-limit
885 This new setting allows the user to control the maximum size of Ada
886 objects being printed when those objects have a variable type,
887 instead of that maximum size being hardcoded to 65536 bytes.
889 set|show record btrace cpu
890 Controls the processor to be used for enabling errata workarounds for
893 maint check libthread-db
894 Run integrity checks on the current inferior's thread debugging
897 maint set check-libthread-db (on|off)
898 maint show check-libthread-db
899 Control whether to run integrity checks on inferior specific thread
900 debugging libraries as they are loaded. The default is not to
905 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
907 ** The commands attached to a breakpoint can be set by assigning to
908 the breakpoint's "commands" field.
910 ** gdb.execute can now execute multi-line gdb commands.
912 ** The new functions gdb.convenience_variable and
913 gdb.set_convenience_variable can be used to get and set the value
914 of convenience variables.
916 ** A gdb.Parameter will no longer print the "set" help text on an
917 ordinary "set"; instead by default a "set" will be silent unless
918 the get_set_string method returns a non-empty string.
922 RiscV ELF riscv*-*-elf
924 * Removed targets and native configurations
926 m88k running OpenBSD m88*-*-openbsd*
927 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
928 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
929 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
931 * Aarch64/Linux hardware watchpoints improvements
933 Hardware watchpoints on unaligned addresses are now properly
934 supported when running Linux kernel 4.10 or higher: read and access
935 watchpoints are no longer spuriously missed, and all watchpoints
936 lengths between 1 and 8 bytes are supported. On older kernels,
937 watchpoints set on unaligned addresses are no longer missed, with
938 the tradeoff that there is a possibility of false hits being
943 --enable-codesign=CERT
944 This can be used to invoke "codesign -s CERT" after building gdb.
945 This option is useful on macOS, where code signing is required for
946 gdb to work properly.
948 --disable-gdbcli has been removed
949 This is now silently accepted, but does nothing.
951 *** Changes in GDB 8.1
953 * GDB now supports dynamically creating arbitrary register groups specified
954 in XML target descriptions. This allows for finer grain grouping of
955 registers on systems with a large amount of registers.
957 * The 'ptype' command now accepts a '/o' flag, which prints the
958 offsets and sizes of fields in a struct, like the pahole(1) tool.
960 * New "--readnever" command line option instructs GDB to not read each
961 symbol file's symbolic debug information. This makes startup faster
962 but at the expense of not being able to perform symbolic debugging.
963 This option is intended for use cases where symbolic debugging will
964 not be used, e.g., when you only need to dump the debuggee's core.
966 * GDB now uses the GNU MPFR library, if available, to emulate target
967 floating-point arithmetic during expression evaluation when the target
968 uses different floating-point formats than the host. At least version
969 3.1 of GNU MPFR is required.
971 * GDB now supports access to the guarded-storage-control registers and the
972 software-based guarded-storage broadcast control registers on IBM z14.
974 * On Unix systems, GDB now supports transmitting environment variables
975 that are to be set or unset to GDBserver. These variables will
976 affect the environment to be passed to the remote inferior.
978 To inform GDB of environment variables that are to be transmitted to
979 GDBserver, use the "set environment" command. Only user set
980 environment variables are sent to GDBserver.
982 To inform GDB of environment variables that are to be unset before
983 the remote inferior is started by the GDBserver, use the "unset
984 environment" command.
986 * Completion improvements
988 ** GDB can now complete function parameters in linespecs and
989 explicit locations without quoting. When setting breakpoints,
990 quoting around functions names to help with TAB-completion is
991 generally no longer necessary. For example, this now completes
994 (gdb) b function(in[TAB]
995 (gdb) b function(int)
997 Related, GDB is no longer confused with completing functions in
998 C++ anonymous namespaces:
1001 (gdb) b (anonymous namespace)::[TAB][TAB]
1002 (anonymous namespace)::a_function()
1003 (anonymous namespace)::b_function()
1005 ** GDB now has much improved linespec and explicit locations TAB
1006 completion support, that better understands what you're
1007 completing and offers better suggestions. For example, GDB no
1008 longer offers data symbols as possible completions when you're
1009 setting a breakpoint.
1011 ** GDB now TAB-completes label symbol names.
1013 ** The "complete" command now mimics TAB completion accurately.
1015 * New command line options (gcore)
1018 Dump all memory mappings.
1020 * Breakpoints on C++ functions are now set on all scopes by default
1022 By default, breakpoints on functions/methods are now interpreted as
1023 specifying all functions with the given name ignoring missing
1024 leading scopes (namespaces and classes).
1026 For example, assuming a C++ program with symbols named:
1031 both commands "break func()" and "break B::func()" set a breakpoint
1034 You can use the new flag "-qualified" to override this. This makes
1035 GDB interpret the specified function name as a complete
1036 fully-qualified name instead. For example, using the same C++
1037 program, the "break -q B::func" command sets a breakpoint on
1038 "B::func", only. A parameter has been added to the Python
1039 gdb.Breakpoint constructor to achieve the same result when creating
1040 a breakpoint from Python.
1042 * Breakpoints on functions marked with C++ ABI tags
1044 GDB can now set breakpoints on functions marked with C++ ABI tags
1045 (e.g., [abi:cxx11]). See here for a description of ABI tags:
1046 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
1048 Functions with a C++11 abi tag are demangled/displayed like this:
1050 function[abi:cxx11](int)
1053 You can now set a breakpoint on such functions simply as if they had
1056 (gdb) b function(int)
1058 Or if you need to disambiguate between tags, like:
1060 (gdb) b function[abi:other_tag](int)
1062 Tab completion was adjusted accordingly as well.
1066 ** New events gdb.new_inferior, gdb.inferior_deleted, and
1067 gdb.new_thread are emitted. See the manual for further
1068 description of these.
1070 ** A new function, "gdb.rbreak" has been added to the Python API.
1071 This function allows the setting of a large number of breakpoints
1072 via a regex pattern in Python. See the manual for further details.
1074 ** Python breakpoints can now accept explicit locations. See the
1075 manual for a further description of this feature.
1078 * New features in the GDB remote stub, GDBserver
1080 ** GDBserver is now able to start inferior processes with a
1081 specified initial working directory.
1083 The user can set the desired working directory to be used from
1084 GDB using the new "set cwd" command.
1086 ** New "--selftest" command line option runs some GDBserver self
1087 tests. These self tests are disabled in releases.
1089 ** On Unix systems, GDBserver now does globbing expansion and variable
1090 substitution in inferior command line arguments.
1092 This is done by starting inferiors using a shell, like GDB does.
1093 See "set startup-with-shell" in the user manual for how to disable
1094 this from GDB when using "target extended-remote". When using
1095 "target remote", you can disable the startup with shell by using the
1096 new "--no-startup-with-shell" GDBserver command line option.
1098 ** On Unix systems, GDBserver now supports receiving environment
1099 variables that are to be set or unset from GDB. These variables
1100 will affect the environment to be passed to the inferior.
1102 * When catching an Ada exception raised with a message, GDB now prints
1103 the message in the catchpoint hit notification. In GDB/MI mode, that
1104 information is provided as an extra field named "exception-message"
1105 in the *stopped notification.
1107 * Trait objects can now be inspected When debugging Rust code. This
1108 requires compiler support which will appear in Rust 1.24.
1110 * New remote packets
1112 QEnvironmentHexEncoded
1113 Inform GDBserver of an environment variable that is to be passed to
1114 the inferior when starting it.
1117 Inform GDBserver of an environment variable that is to be unset
1118 before starting the remote inferior.
1121 Inform GDBserver that the environment should be reset (i.e.,
1122 user-set environment variables should be unset).
1125 Indicates whether the inferior must be started with a shell or not.
1128 Tell GDBserver that the inferior to be started should use a specific
1131 * The "maintenance print c-tdesc" command now takes an optional
1132 argument which is the file name of XML target description.
1134 * The "maintenance selftest" command now takes an optional argument to
1135 filter the tests to be run.
1137 * The "enable", and "disable" commands now accept a range of
1138 breakpoint locations, e.g. "enable 1.3-5".
1143 Set and show the current working directory for the inferior.
1145 set|show compile-gcc
1146 Set and show compilation command used for compiling and injecting code
1147 with the 'compile' commands.
1149 set debug separate-debug-file
1150 show debug separate-debug-file
1151 Control the display of debug output about separate debug file search.
1153 set dump-excluded-mappings
1154 show dump-excluded-mappings
1155 Control whether mappings marked with the VM_DONTDUMP flag should be
1156 dumped when generating a core file.
1158 maint info selftests
1159 List the registered selftests.
1162 Start the debugged program stopping at the first instruction.
1165 Control display of debugging messages related to OpenRISC targets.
1167 set|show print type nested-type-limit
1168 Set and show the limit of nesting level for nested types that the
1169 type printer will show.
1171 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
1174 * Safer/improved support for debugging with no debug info
1176 GDB no longer assumes functions with no debug information return
1179 This means that GDB now refuses to call such functions unless you
1180 tell it the function's type, by either casting the call to the
1181 declared return type, or by casting the function to a function
1182 pointer of the right type, and calling that:
1184 (gdb) p getenv ("PATH")
1185 'getenv' has unknown return type; cast the call to its declared return type
1186 (gdb) p (char *) getenv ("PATH")
1187 $1 = 0x7fffffffe "/usr/local/bin:/"...
1188 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
1189 $2 = 0x7fffffffe "/usr/local/bin:/"...
1191 Similarly, GDB no longer assumes that global variables with no debug
1192 info have type 'int', and refuses to print the variable's value
1193 unless you tell it the variable's type:
1196 'var' has unknown type; cast it to its declared type
1200 * New native configurations
1202 FreeBSD/aarch64 aarch64*-*-freebsd*
1203 FreeBSD/arm arm*-*-freebsd*
1207 FreeBSD/aarch64 aarch64*-*-freebsd*
1208 FreeBSD/arm arm*-*-freebsd*
1209 OpenRISC ELF or1k*-*-elf
1211 * Removed targets and native configurations
1213 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
1215 *** Changes in GDB 8.0
1217 * GDB now supports access to the PKU register on GNU/Linux. The register is
1218 added by the Memory Protection Keys for Userspace feature which will be
1219 available in future Intel CPUs.
1221 * GDB now supports C++11 rvalue references.
1225 ** New functions to start, stop and access a running btrace recording.
1226 ** Rvalue references are now supported in gdb.Type.
1228 * GDB now supports recording and replaying rdrand and rdseed Intel 64
1231 * Building GDB and GDBserver now requires a C++11 compiler.
1233 For example, GCC 4.8 or later.
1235 It is no longer possible to build GDB or GDBserver with a C
1236 compiler. The --disable-build-with-cxx configure option has been
1239 * Building GDB and GDBserver now requires GNU make >= 3.81.
1241 It is no longer supported to build GDB or GDBserver with another
1242 implementation of the make program or an earlier version of GNU make.
1244 * Native debugging on MS-Windows supports command-line redirection
1246 Command-line arguments used for starting programs on MS-Windows can
1247 now include redirection symbols supported by native Windows shells,
1248 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
1249 as "run", "start", and "set args", as well as the corresponding MI
1252 * Support for thread names on MS-Windows.
1254 GDB now catches and handles the special exception that programs
1255 running on MS-Windows use to assign names to threads in the
1258 * Support for Java programs compiled with gcj has been removed.
1260 * User commands now accept an unlimited number of arguments.
1261 Previously, only up to 10 was accepted.
1263 * The "eval" command now expands user-defined command arguments.
1265 This makes it easier to process a variable number of arguments:
1270 eval "print $arg%d", $i
1275 * Target descriptions can now describe registers for sparc32 and sparc64.
1277 * GDB now supports DWARF version 5 (debug information format).
1278 Its .debug_names index is not yet supported.
1280 * New native configurations
1282 FreeBSD/mips mips*-*-freebsd
1286 Synopsys ARC arc*-*-elf32
1287 FreeBSD/mips mips*-*-freebsd
1289 * Removed targets and native configurations
1291 Alpha running FreeBSD alpha*-*-freebsd*
1292 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
1297 Erases all the flash memory regions reported by the target.
1299 maint print arc arc-instruction address
1300 Print internal disassembler information about instruction at a given address.
1304 set disassembler-options
1305 show disassembler-options
1306 Controls the passing of target specific information to the disassembler.
1307 If it is necessary to specify more than one disassembler option then
1308 multiple options can be placed together into a comma separated list.
1309 The default value is the empty string. Currently, the only supported
1310 targets are ARM, PowerPC and S/390.
1315 Erases all the flash memory regions reported by the target. This is
1316 equivalent to the CLI command flash-erase.
1318 -file-list-shared-libraries
1319 List the shared libraries in the program. This is
1320 equivalent to the CLI command "info shared".
1323 Catchpoints stopping the program when Ada exceptions are
1324 handled. This is equivalent to the CLI command "catch handlers".
1326 *** Changes in GDB 7.12
1328 * GDB and GDBserver now build with a C++ compiler by default.
1330 The --enable-build-with-cxx configure option is now enabled by
1331 default. One must now explicitly configure with
1332 --disable-build-with-cxx in order to build with a C compiler. This
1333 option will be removed in a future release.
1335 * GDBserver now supports recording btrace without maintaining an active
1338 * GDB now supports a negative repeat count in the 'x' command to examine
1339 memory backward from the given address. For example:
1342 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
1343 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
1344 (gdb) x/-5i 0x0000000000400580
1345 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
1346 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
1347 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
1348 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
1349 0x40057b <main(int, char**)+25>:
1350 callq 0x400536 <Func1(int, char const*)>
1352 * Fortran: Support structures with fields of dynamic types and
1353 arrays of dynamic types.
1355 * The symbol dumping maintenance commands have new syntax.
1356 maint print symbols [-pc address] [--] [filename]
1357 maint print symbols [-objfile objfile] [-source source] [--] [filename]
1358 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
1359 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
1360 maint print msymbols [-objfile objfile] [--] [filename]
1362 * GDB now supports multibit bitfields and enums in target register
1365 * New Python-based convenience function $_as_string(val), which returns
1366 the textual representation of a value. This function is especially
1367 useful to obtain the text label of an enum value.
1369 * Intel MPX bound violation handling.
1371 Segmentation faults caused by a Intel MPX boundary violation
1372 now display the kind of violation (upper or lower), the memory
1373 address accessed and the memory bounds, along with the usual
1374 signal received and code location.
1378 Program received signal SIGSEGV, Segmentation fault
1379 Upper bound violation while accessing address 0x7fffffffc3b3
1380 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
1381 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
1383 * Rust language support.
1384 GDB now supports debugging programs written in the Rust programming
1385 language. See https://www.rust-lang.org/ for more information about
1388 * Support for running interpreters on specified input/output devices
1390 GDB now supports a new mechanism that allows frontends to provide
1391 fully featured GDB console views, as a better alternative to
1392 building such views on top of the "-interpreter-exec console"
1393 command. See the new "new-ui" command below. With that command,
1394 frontends can now start GDB in the traditional command-line mode
1395 running in an embedded terminal emulator widget, and create a
1396 separate MI interpreter running on a specified i/o device. In this
1397 way, GDB handles line editing, history, tab completion, etc. in the
1398 console all by itself, and the GUI uses the separate MI interpreter
1399 for its own control and synchronization, invisible to the command
1402 * The "catch syscall" command catches groups of related syscalls.
1404 The "catch syscall" command now supports catching a group of related
1405 syscalls using the 'group:' or 'g:' prefix.
1410 skip -gfile file-glob-pattern
1411 skip -function function
1412 skip -rfunction regular-expression
1413 A generalized form of the skip command, with new support for
1414 glob-style file names and regular expressions for function names.
1415 Additionally, a file spec and a function spec may now be combined.
1417 maint info line-table REGEXP
1418 Display the contents of GDB's internal line table data structure.
1421 Run any GDB unit tests that were compiled in.
1424 Start a new user interface instance running INTERP as interpreter,
1425 using the TTY file for input/output.
1429 ** gdb.Breakpoint objects have a new attribute "pending", which
1430 indicates whether the breakpoint is pending.
1431 ** Three new breakpoint-related events have been added:
1432 gdb.breakpoint_created, gdb.breakpoint_modified, and
1433 gdb.breakpoint_deleted.
1435 signal-event EVENTID
1436 Signal ("set") the given MS-Windows event object. This is used in
1437 conjunction with the Windows JIT debugging (AeDebug) support, where
1438 the OS suspends a crashing process until a debugger can attach to
1439 it. Resuming the crashing process, in order to debug it, is done by
1440 signalling an event.
1442 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
1443 was added in GDBserver, including JIT compiling fast tracepoint's
1444 conditional expression bytecode into native code.
1446 * Support for various remote target protocols and ROM monitors has
1449 target m32rsdi Remote M32R debugging over SDI
1450 target mips MIPS remote debugging protocol
1451 target pmon PMON ROM monitor
1452 target ddb NEC's DDB variant of PMON for Vr4300
1453 target rockhopper NEC RockHopper variant of PMON
1454 target lsi LSI variant of PMO
1456 * Support for tracepoints and fast tracepoints on powerpc-linux,
1457 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
1458 including JIT compiling fast tracepoint's conditional expression
1459 bytecode into native code.
1461 * MI async record =record-started now includes the method and format used for
1462 recording. For example:
1464 =record-started,thread-group="i1",method="btrace",format="bts"
1466 * MI async record =thread-selected now includes the frame field. For example:
1468 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
1472 Andes NDS32 nds32*-*-elf
1474 *** Changes in GDB 7.11
1476 * GDB now supports debugging kernel-based threads on FreeBSD.
1478 * Per-inferior thread numbers
1480 Thread numbers are now per inferior instead of global. If you're
1481 debugging multiple inferiors, GDB displays thread IDs using a
1482 qualified INF_NUM.THR_NUM form. For example:
1486 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
1487 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1488 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1489 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1491 As consequence, thread numbers as visible in the $_thread
1492 convenience variable and in Python's InferiorThread.num attribute
1493 are no longer unique between inferiors.
1495 GDB now maintains a second thread ID per thread, referred to as the
1496 global thread ID, which is the new equivalent of thread numbers in
1497 previous releases. See also $_gthread below.
1499 For backwards compatibility, MI's thread IDs always refer to global
1502 * Commands that accept thread IDs now accept the qualified
1503 INF_NUM.THR_NUM form as well. For example:
1506 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1509 * In commands that accept a list of thread IDs, you can now refer to
1510 all threads of an inferior using a star wildcard. GDB accepts
1511 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1512 refer to all threads of the current inferior. For example, "info
1515 * You can use "info threads -gid" to display the global thread ID of
1518 * The new convenience variable $_gthread holds the global number of
1521 * The new convenience variable $_inferior holds the number of the
1524 * GDB now displays the ID and name of the thread that hit a breakpoint
1525 or received a signal, if your program is multi-threaded. For
1528 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1529 Thread 1 "main" received signal SIGINT, Interrupt.
1531 * Record btrace now supports non-stop mode.
1533 * Support for tracepoints on aarch64-linux was added in GDBserver.
1535 * The 'record instruction-history' command now indicates speculative execution
1536 when using the Intel Processor Trace recording format.
1538 * GDB now allows users to specify explicit locations, bypassing
1539 the linespec parser. This feature is also available to GDB/MI
1542 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1543 GDB now is able to debug both AArch64 applications and ARM applications
1546 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1547 including JIT compiling fast tracepoint's conditional expression bytecode
1550 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1552 * "info threads", "info inferiors", "info display", "info checkpoints"
1553 and "maint info program-spaces" now list the corresponding items in
1554 ascending ID order, for consistency with all other "info" commands.
1556 * In Ada, the overloads selection menu has been enhanced to display the
1557 parameter types and the return types for the matching overloaded subprograms.
1561 maint set target-non-stop (on|off|auto)
1562 maint show target-non-stop
1563 Control whether GDB targets always operate in non-stop mode even if
1564 "set non-stop" is "off". The default is "auto", meaning non-stop
1565 mode is enabled if supported by the target.
1567 maint set bfd-sharing
1568 maint show bfd-sharing
1569 Control the reuse of bfd objects.
1572 show debug bfd-cache
1573 Control display of debugging info regarding bfd caching.
1577 Control display of debugging info regarding FreeBSD threads.
1579 set remote multiprocess-extensions-packet
1580 show remote multiprocess-extensions-packet
1581 Set/show the use of the remote protocol multiprocess extensions.
1583 set remote thread-events
1584 show remote thread-events
1585 Set/show the use of thread create/exit events.
1587 set ada print-signatures on|off
1588 show ada print-signatures"
1589 Control whether parameter types and return types are displayed in overloads
1590 selection menus. It is activated (@code{on}) by default.
1594 Controls the maximum size of memory, in bytes, that GDB will
1595 allocate for value contents. Prevents incorrect programs from
1596 causing GDB to allocate overly large buffers. Default is 64k.
1598 * The "disassemble" command accepts a new modifier: /s.
1599 It prints mixed source+disassembly like /m with two differences:
1600 - disassembled instructions are now printed in program order, and
1601 - and source for all relevant files is now printed.
1602 The "/m" option is now considered deprecated: its "source-centric"
1603 output hasn't proved useful in practice.
1605 * The "record instruction-history" command accepts a new modifier: /s.
1606 It behaves exactly like /m and prints mixed source+disassembly.
1608 * The "set scheduler-locking" command supports a new mode "replay".
1609 It behaves like "off" in record mode and like "on" in replay mode.
1611 * Support for various ROM monitors has been removed:
1613 target dbug dBUG ROM monitor for Motorola ColdFire
1614 target picobug Motorola picobug monitor
1615 target dink32 DINK32 ROM monitor for PowerPC
1616 target m32r Renesas M32R/D ROM monitor
1617 target mon2000 mon2000 ROM monitor
1618 target ppcbug PPCBUG ROM monitor for PowerPC
1620 * Support for reading/writing memory and extracting values on architectures
1621 whose memory is addressable in units of any integral multiple of 8 bits.
1624 Allows to break when an Ada exception is handled.
1626 * New remote packets
1629 Indicates that an exec system call was executed.
1631 exec-events feature in qSupported
1632 The qSupported packet allows GDB to request support for exec
1633 events using the new 'gdbfeature' exec-event, and the qSupported
1634 response can contain the corresponding 'stubfeature'. Set and
1635 show commands can be used to display whether these features are enabled.
1638 Equivalent to interrupting with the ^C character, but works in
1641 thread created stop reason (T05 create:...)
1642 Indicates that the thread was just created and is stopped at entry.
1644 thread exit stop reply (w exitcode;tid)
1645 Indicates that the thread has terminated.
1648 Enables/disables thread create and exit event reporting. For
1649 example, this is used in non-stop mode when GDB stops a set of
1650 threads and synchronously waits for the their corresponding stop
1651 replies. Without exit events, if one of the threads exits, GDB
1652 would hang forever not knowing that it should no longer expect a
1653 stop for that same thread.
1656 Indicates that there are no resumed threads left in the target (all
1657 threads are stopped). The remote stub reports support for this stop
1658 reply to GDB's qSupported query.
1661 Enables/disables catching syscalls from the inferior process.
1662 The remote stub reports support for this packet to GDB's qSupported query.
1664 syscall_entry stop reason
1665 Indicates that a syscall was just called.
1667 syscall_return stop reason
1668 Indicates that a syscall just returned.
1670 * Extended-remote exec events
1672 ** GDB now has support for exec events on extended-remote Linux targets.
1673 For such targets with Linux kernels 2.5.46 and later, this enables
1674 follow-exec-mode and exec catchpoints.
1676 set remote exec-event-feature-packet
1677 show remote exec-event-feature-packet
1678 Set/show the use of the remote exec event feature.
1680 * Thread names in remote protocol
1682 The reply to qXfer:threads:read may now include a name attribute for each
1685 * Target remote mode fork and exec events
1687 ** GDB now has support for fork and exec events on target remote mode
1688 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1689 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1690 fork and exec catchpoints.
1692 * Remote syscall events
1694 ** GDB now has support for catch syscall on remote Linux targets,
1695 currently enabled on x86/x86_64 architectures.
1697 set remote catch-syscall-packet
1698 show remote catch-syscall-packet
1699 Set/show the use of the remote catch syscall feature.
1703 ** The -var-set-format command now accepts the zero-hexadecimal
1704 format. It outputs data in hexadecimal format with zero-padding on the
1709 ** gdb.InferiorThread objects have a new attribute "global_num",
1710 which refers to the thread's global thread ID. The existing
1711 "num" attribute now refers to the thread's per-inferior number.
1712 See "Per-inferior thread numbers" above.
1713 ** gdb.InferiorThread objects have a new attribute "inferior", which
1714 is the Inferior object the thread belongs to.
1716 *** Changes in GDB 7.10
1718 * Support for process record-replay and reverse debugging on aarch64*-linux*
1719 targets has been added. GDB now supports recording of A64 instruction set
1720 including advance SIMD instructions.
1722 * Support for Sun's version of the "stabs" debug file format has been removed.
1724 * GDB now honors the content of the file /proc/PID/coredump_filter
1725 (PID is the process ID) on GNU/Linux systems. This file can be used
1726 to specify the types of memory mappings that will be included in a
1727 corefile. For more information, please refer to the manual page of
1728 "core(5)". GDB also has a new command: "set use-coredump-filter
1729 on|off". It allows to set whether GDB will read the content of the
1730 /proc/PID/coredump_filter file when generating a corefile.
1732 * The "info os" command on GNU/Linux can now display information on
1734 "info os cpus" Listing of all cpus/cores on the system
1736 * GDB has two new commands: "set serial parity odd|even|none" and
1737 "show serial parity". These allows to set or show parity for the
1740 * The "info source" command now displays the producer string if it was
1741 present in the debug info. This typically includes the compiler version
1742 and may include things like its command line arguments.
1744 * The "info dll", an alias of the "info sharedlibrary" command,
1745 is now available on all platforms.
1747 * Directory names supplied to the "set sysroot" commands may be
1748 prefixed with "target:" to tell GDB to access shared libraries from
1749 the target system, be it local or remote. This replaces the prefix
1750 "remote:". The default sysroot has been changed from "" to
1751 "target:". "remote:" is automatically converted to "target:" for
1752 backward compatibility.
1754 * The system root specified by "set sysroot" will be prepended to the
1755 filename of the main executable (if reported to GDB as absolute by
1756 the operating system) when starting processes remotely, and when
1757 attaching to already-running local or remote processes.
1759 * GDB now supports automatic location and retrieval of executable
1760 files from remote targets. Remote debugging can now be initiated
1761 using only a "target remote" or "target extended-remote" command
1762 (no "set sysroot" or "file" commands are required). See "New remote
1765 * The "dump" command now supports verilog hex format.
1767 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
1769 * On GNU/Linux, GDB and gdbserver are now able to access executable
1770 and shared library files without a "set sysroot" command when
1771 attaching to processes running in different mount namespaces from
1772 the debugger. This makes it possible to attach to processes in
1773 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
1774 See "New remote packets" below.
1776 * The "tui reg" command now provides completion for all of the
1777 available register groups, including target specific groups.
1779 * The HISTSIZE environment variable is no longer read when determining
1780 the size of GDB's command history. GDB now instead reads the dedicated
1781 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
1782 disables truncation of command history. Non-numeric values of GDBHISTSIZE
1787 ** Memory ports can now be unbuffered.
1791 ** gdb.Objfile objects have a new attribute "username",
1792 which is the name of the objfile as specified by the user,
1793 without, for example, resolving symlinks.
1794 ** You can now write frame unwinders in Python.
1795 ** gdb.Type objects have a new method "optimized_out",
1796 returning optimized out gdb.Value instance of this type.
1797 ** gdb.Value objects have new methods "reference_value" and
1798 "const_value" which return a reference to the value and a
1799 "const" version of the value respectively.
1803 maint print symbol-cache
1804 Print the contents of the symbol cache.
1806 maint print symbol-cache-statistics
1807 Print statistics of symbol cache usage.
1809 maint flush-symbol-cache
1810 Flush the contents of the symbol cache.
1814 Start branch trace recording using Branch Trace Store (BTS) format.
1817 Evaluate expression by using the compiler and print result.
1821 Explicit commands for enabling and disabling tui mode.
1824 set mpx bound on i386 and amd64
1825 Support for bound table investigation on Intel MPX enabled applications.
1829 Start branch trace recording using Intel Processor Trace format.
1832 Print information about branch tracing internals.
1834 maint btrace packet-history
1835 Print the raw branch tracing data.
1837 maint btrace clear-packet-history
1838 Discard the stored raw branch tracing data.
1841 Discard all branch tracing data. It will be fetched and processed
1842 anew by the next "record" command.
1847 Renamed from "set debug dwarf2-die".
1848 show debug dwarf-die
1849 Renamed from "show debug dwarf2-die".
1851 set debug dwarf-read
1852 Renamed from "set debug dwarf2-read".
1853 show debug dwarf-read
1854 Renamed from "show debug dwarf2-read".
1856 maint set dwarf always-disassemble
1857 Renamed from "maint set dwarf2 always-disassemble".
1858 maint show dwarf always-disassemble
1859 Renamed from "maint show dwarf2 always-disassemble".
1861 maint set dwarf max-cache-age
1862 Renamed from "maint set dwarf2 max-cache-age".
1863 maint show dwarf max-cache-age
1864 Renamed from "maint show dwarf2 max-cache-age".
1866 set debug dwarf-line
1867 show debug dwarf-line
1868 Control display of debugging info regarding DWARF line processing.
1871 show max-completions
1872 Set the maximum number of candidates to be considered during
1873 completion. The default value is 200. This limit allows GDB
1874 to avoid generating large completion lists, the computation of
1875 which can cause the debugger to become temporarily unresponsive.
1877 set history remove-duplicates
1878 show history remove-duplicates
1879 Control the removal of duplicate history entries.
1881 maint set symbol-cache-size
1882 maint show symbol-cache-size
1883 Control the size of the symbol cache.
1885 set|show record btrace bts buffer-size
1886 Set and show the size of the ring buffer used for branch tracing in
1888 The obtained size may differ from the requested size. Use "info
1889 record" to see the obtained buffer size.
1891 set debug linux-namespaces
1892 show debug linux-namespaces
1893 Control display of debugging info regarding Linux namespaces.
1895 set|show record btrace pt buffer-size
1896 Set and show the size of the ring buffer used for branch tracing in
1897 Intel Processor Trace format.
1898 The obtained size may differ from the requested size. Use "info
1899 record" to see the obtained buffer size.
1901 maint set|show btrace pt skip-pad
1902 Set and show whether PAD packets are skipped when computing the
1905 * The command 'thread apply all' can now support new option '-ascending'
1906 to call its specified command for all threads in ascending order.
1908 * Python/Guile scripting
1910 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1911 special section named `.debug_gdb_scripts'.
1913 * New remote packets
1915 qXfer:btrace-conf:read
1916 Return the branch trace configuration for the current thread.
1918 Qbtrace-conf:bts:size
1919 Set the requested ring buffer size for branch tracing in BTS format.
1922 Enable Intel Processor Trace-based branch tracing for the current
1923 process. The remote stub reports support for this packet to GDB's
1926 Qbtrace-conf:pt:size
1927 Set the requested ring buffer size for branch tracing in Intel Processor
1931 Indicates a memory breakpoint instruction was executed, irrespective
1932 of whether it was GDB that planted the breakpoint or the breakpoint
1933 is hardcoded in the program. This is required for correct non-stop
1937 Indicates the target stopped for a hardware breakpoint. This is
1938 required for correct non-stop mode operation.
1941 Return information about files on the remote system.
1943 qXfer:exec-file:read
1944 Return the full absolute name of the file that was executed to
1945 create a process running on the remote system.
1948 Select the filesystem on which vFile: operations with filename
1949 arguments will operate. This is required for GDB to be able to
1950 access files on remote targets where the remote stub does not
1951 share a common filesystem with the inferior(s).
1954 Indicates that a fork system call was executed.
1957 Indicates that a vfork system call was executed.
1959 vforkdone stop reason
1960 Indicates that a vfork child of the specified process has executed
1961 an exec or exit, allowing the vfork parent to resume execution.
1963 fork-events and vfork-events features in qSupported
1964 The qSupported packet allows GDB to request support for fork and
1965 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1966 and the qSupported response can contain the corresponding
1967 'stubfeatures'. Set and show commands can be used to display
1968 whether these features are enabled.
1970 * Extended-remote fork events
1972 ** GDB now has support for fork events on extended-remote Linux
1973 targets. For targets with Linux kernels 2.5.60 and later, this
1974 enables follow-fork-mode and detach-on-fork for both fork and
1975 vfork, as well as fork and vfork catchpoints.
1977 * The info record command now shows the recording format and the
1978 branch tracing configuration for the current thread when using
1979 the btrace record target.
1980 For the BTS format, it shows the ring buffer size.
1982 * GDB now has support for DTrace USDT (Userland Static Defined
1983 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1985 * GDB now supports access to vector registers on S/390 GNU/Linux
1988 * Removed command line options
1990 -xdb HP-UX XDB compatibility mode.
1992 * Removed targets and native configurations
1994 HP/PA running HP-UX hppa*-*-hpux*
1995 Itanium running HP-UX ia64-*-hpux*
1997 * New configure options
2000 This configure option allows the user to build GDB with support for
2001 Intel Processor Trace (default: auto). This requires libipt.
2003 --with-libipt-prefix=PATH
2004 Specify the path to the version of libipt that GDB should use.
2005 $PATH/include should contain the intel-pt.h header and
2006 $PATH/lib should contain the libipt.so library.
2008 *** Changes in GDB 7.9.1
2012 ** Xmethods can now specify a result type.
2014 *** Changes in GDB 7.9
2016 * GDB now supports hardware watchpoints on x86 GNU Hurd.
2020 ** You can now access frame registers from Python scripts.
2021 ** New attribute 'producer' for gdb.Symtab objects.
2022 ** gdb.Objfile objects have a new attribute "progspace",
2023 which is the gdb.Progspace object of the containing program space.
2024 ** gdb.Objfile objects have a new attribute "owner".
2025 ** gdb.Objfile objects have a new attribute "build_id",
2026 which is the build ID generated when the file was built.
2027 ** gdb.Objfile objects have a new method "add_separate_debug_file".
2028 ** A new event "gdb.clear_objfiles" has been added, triggered when
2029 selecting a new file to debug.
2030 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
2031 ** New function gdb.lookup_objfile.
2033 New events which are triggered when GDB modifies the state of the
2036 ** gdb.events.inferior_call_pre: Function call is about to be made.
2037 ** gdb.events.inferior_call_post: Function call has just been made.
2038 ** gdb.events.memory_changed: A memory location has been altered.
2039 ** gdb.events.register_changed: A register has been altered.
2041 * New Python-based convenience functions:
2043 ** $_caller_is(name [, number_of_frames])
2044 ** $_caller_matches(regexp [, number_of_frames])
2045 ** $_any_caller_is(name [, number_of_frames])
2046 ** $_any_caller_matches(regexp [, number_of_frames])
2048 * GDB now supports the compilation and injection of source code into
2049 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
2050 to compile the source code to object code, and if successful, inject
2051 and execute that code within the current context of the inferior.
2052 Currently the C language is supported. The commands used to
2053 interface with this new feature are:
2055 compile code [-raw|-r] [--] [source code]
2056 compile file [-raw|-r] filename
2060 demangle [-l language] [--] name
2061 Demangle "name" in the specified language, or the current language
2062 if elided. This command is renamed from the "maint demangle" command.
2063 The latter is kept as a no-op to avoid "maint demangle" being interpreted
2064 as "maint demangler-warning".
2066 queue-signal signal-name-or-number
2067 Queue a signal to be delivered to the thread when it is resumed.
2069 add-auto-load-scripts-directory directory
2070 Add entries to the list of directories from which to load auto-loaded
2073 maint print user-registers
2074 List all currently available "user" registers.
2076 compile code [-r|-raw] [--] [source code]
2077 Compile, inject, and execute in the inferior the executable object
2078 code produced by compiling the provided source code.
2080 compile file [-r|-raw] filename
2081 Compile and inject into the inferior the executable object code
2082 produced by compiling the source code stored in the filename
2085 * On resume, GDB now always passes the signal the program had stopped
2086 for to the thread the signal was sent to, even if the user changed
2087 threads before resuming. Previously GDB would often (but not
2088 always) deliver the signal to the thread that happens to be current
2091 * Conversely, the "signal" command now consistently delivers the
2092 requested signal to the current thread. GDB now asks for
2093 confirmation if the program had stopped for a signal and the user
2094 switched threads meanwhile.
2096 * "breakpoint always-inserted" modes "off" and "auto" merged.
2098 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
2099 won't remove breakpoints from the target until all threads stop,
2100 even in non-stop mode. The "auto" mode has been removed, and "off"
2101 is now the default mode.
2105 set debug symbol-lookup
2106 show debug symbol-lookup
2107 Control display of debugging info regarding symbol lookup.
2111 ** The -list-thread-groups command outputs an exit-code field for
2112 inferiors that have exited.
2116 MIPS SDE mips*-sde*-elf*
2120 Support for these obsolete configurations has been removed.
2122 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
2123 SGI Irix-5.x mips-*-irix5*
2124 SGI Irix-6.x mips-*-irix6*
2125 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
2126 VAX running Ultrix vax-*-ultrix*
2128 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2129 and "assf"), have been removed. Use the "sharedlibrary" command, or
2130 its alias "share", instead.
2132 *** Changes in GDB 7.8
2134 * New command line options
2137 This is an alias for the --data-directory option.
2139 * GDB supports printing and modifying of variable length automatic arrays
2140 as specified in ISO C99.
2142 * The ARM simulator now supports instruction level tracing
2143 with or without disassembly.
2147 GDB now has support for scripting using Guile. Whether this is
2148 available is determined at configure time.
2149 Guile version 2.0 or greater is required.
2150 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
2152 * New commands (for set/show, see "New options" below)
2156 Invoke CODE by passing it to the Guile interpreter.
2160 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
2162 info auto-load guile-scripts [regexp]
2163 Print the list of automatically loaded Guile scripts.
2165 * The source command is now capable of sourcing Guile scripts.
2166 This feature is dependent on the debugger being built with Guile support.
2170 set print symbol-loading (off|brief|full)
2171 show print symbol-loading
2172 Control whether to print informational messages when loading symbol
2173 information for a file. The default is "full", but when debugging
2174 programs with large numbers of shared libraries the amount of output
2175 becomes less useful.
2177 set guile print-stack (none|message|full)
2178 show guile print-stack
2179 Show a stack trace when an error is encountered in a Guile script.
2181 set auto-load guile-scripts (on|off)
2182 show auto-load guile-scripts
2183 Control auto-loading of Guile script files.
2185 maint ada set ignore-descriptive-types (on|off)
2186 maint ada show ignore-descriptive-types
2187 Control whether the debugger should ignore descriptive types in Ada
2188 programs. The default is not to ignore the descriptive types. See
2189 the user manual for more details on descriptive types and the intended
2190 usage of this option.
2192 set auto-connect-native-target
2194 Control whether GDB is allowed to automatically connect to the
2195 native target for the run, attach, etc. commands when not connected
2196 to any target yet. See also "target native" below.
2198 set record btrace replay-memory-access (read-only|read-write)
2199 show record btrace replay-memory-access
2200 Control what memory accesses are allowed during replay.
2202 maint set target-async (on|off)
2203 maint show target-async
2204 This controls whether GDB targets operate in synchronous or
2205 asynchronous mode. Normally the default is asynchronous, if it is
2206 available; but this can be changed to more easily debug problems
2207 occurring only in synchronous mode.
2209 set mi-async (on|off)
2211 Control whether MI asynchronous mode is preferred. This supersedes
2212 "set target-async" of previous GDB versions.
2214 * "set target-async" is deprecated as a CLI option and is now an alias
2215 for "set mi-async" (only puts MI into async mode).
2217 * Background execution commands (e.g., "c&", "s&", etc.) are now
2218 possible ``out of the box'' if the target supports them. Previously
2219 the user would need to explicitly enable the possibility with the
2220 "set target-async on" command.
2222 * New features in the GDB remote stub, GDBserver
2224 ** New option --debug-format=option1[,option2,...] allows one to add
2225 additional text to each output. At present only timestamps
2226 are supported: --debug-format=timestamps.
2227 Timestamps can also be turned on with the
2228 "monitor set debug-format timestamps" command from GDB.
2230 * The 'record instruction-history' command now starts counting instructions
2231 at one. This also affects the instruction ranges reported by the
2232 'record function-call-history' command when given the /i modifier.
2234 * The command 'record function-call-history' supports a new modifier '/c' to
2235 indent the function names based on their call stack depth.
2236 The fields for the '/i' and '/l' modifier have been reordered.
2237 The source line range is now prefixed with 'at'.
2238 The instruction range is now prefixed with 'inst'.
2239 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
2240 "record instruction-history" and "list" commands.
2242 * The ranges given as arguments to the 'record function-call-history' and
2243 'record instruction-history' commands are now inclusive.
2245 * The btrace record target now supports the 'record goto' command.
2246 For locations inside the execution trace, the back trace is computed
2247 based on the information stored in the execution trace.
2249 * The btrace record target supports limited reverse execution and replay.
2250 The target does not record data and therefore does not allow reading
2251 memory or registers.
2253 * The "catch syscall" command now works on s390*-linux* targets.
2255 * The "compare-sections" command is no longer specific to target
2256 remote. It now works with all targets.
2258 * All native targets are now consistently called "native".
2259 Consequently, the "target child", "target GNU", "target djgpp",
2260 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
2261 commands have been replaced with "target native". The QNX/NTO port
2262 leaves the "procfs" target in place and adds a "native" target for
2263 consistency with other ports. The impact on users should be minimal
2264 as these commands previously either throwed an error, or were
2265 no-ops. The target's name is visible in the output of the following
2266 commands: "help target", "info target", "info files", "maint print
2269 * The "target native" command now connects to the native target. This
2270 can be used to launch native programs even when "set
2271 auto-connect-native-target" is set to off.
2273 * GDB now supports access to Intel MPX registers on GNU/Linux.
2275 * Support for Intel AVX-512 registers on GNU/Linux.
2276 Support displaying and modifying Intel AVX-512 registers
2277 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
2279 * New remote packets
2281 qXfer:btrace:read's annex
2282 The qXfer:btrace:read packet supports a new annex 'delta' to read
2283 branch trace incrementally.
2287 ** Valid Python operations on gdb.Value objects representing
2288 structs/classes invoke the corresponding overloaded operators if
2290 ** New `Xmethods' feature in the Python API. Xmethods are
2291 additional methods or replacements for existing methods of a C++
2292 class. This feature is useful for those cases where a method
2293 defined in C++ source code could be inlined or optimized out by
2294 the compiler, making it unavailable to GDB.
2297 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
2299 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2300 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
2301 its alias "share", instead.
2303 * The commands "set remotebaud" and "show remotebaud" are no longer
2304 supported. Use "set serial baud" and "show serial baud" (respectively)
2309 ** A new option "-gdb-set mi-async" replaces "-gdb-set
2310 target-async". The latter is left as a deprecated alias of the
2311 former for backward compatibility. If the target supports it,
2312 CLI background execution commands are now always possible by
2313 default, independently of whether the frontend stated a
2314 preference for asynchronous execution with "-gdb-set mi-async".
2315 Previously "-gdb-set target-async off" affected both MI execution
2316 commands and CLI execution commands.
2318 *** Changes in GDB 7.7
2320 * Improved support for process record-replay and reverse debugging on
2321 arm*-linux* targets. Support for thumb32 and syscall instruction
2322 recording has been added.
2324 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
2326 * GDB now supports Fission DWP file format version 2.
2327 http://gcc.gnu.org/wiki/DebugFission
2329 * New convenience function "$_isvoid", to check whether an expression
2330 is void. A void expression is an expression where the type of the
2331 result is "void". For example, some convenience variables may be
2332 "void" when evaluated (e.g., "$_exitcode" before the execution of
2333 the program being debugged; or an undefined convenience variable).
2334 Another example, when calling a function whose return type is
2337 * The "maintenance print objfiles" command now takes an optional regexp.
2339 * The "catch syscall" command now works on arm*-linux* targets.
2341 * GDB now consistently shows "<not saved>" when printing values of
2342 registers the debug info indicates have not been saved in the frame
2343 and there's nowhere to retrieve them from
2344 (callee-saved/call-clobbered registers):
2349 (gdb) info registers rax
2352 Before, the former would print "<optimized out>", and the latter
2353 "*value not available*".
2355 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
2360 ** Frame filters and frame decorators have been added.
2361 ** Temporary breakpoints are now supported.
2362 ** Line tables representation has been added.
2363 ** New attribute 'parent_type' for gdb.Field objects.
2364 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
2365 ** New attribute 'name' for gdb.Type objects.
2369 Nios II ELF nios2*-*-elf
2370 Nios II GNU/Linux nios2*-*-linux
2371 Texas Instruments MSP430 msp430*-*-elf
2373 * Removed native configurations
2375 Support for these a.out NetBSD and OpenBSD obsolete configurations has
2376 been removed. ELF variants of these configurations are kept supported.
2378 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
2379 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
2380 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
2381 i[34567]86-*-openbsd3.[0-3]
2382 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
2383 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
2384 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
2388 Like "catch throw", but catches a re-thrown exception.
2389 maint check-psymtabs
2390 Renamed from old "maint check-symtabs".
2392 Perform consistency checks on symtabs.
2393 maint expand-symtabs
2394 Expand symtabs matching an optional regexp.
2397 Display the details of GDB configure-time options.
2399 maint set|show per-command
2400 maint set|show per-command space
2401 maint set|show per-command time
2402 maint set|show per-command symtab
2403 Enable display of per-command gdb resource usage.
2405 remove-symbol-file FILENAME
2406 remove-symbol-file -a ADDRESS
2407 Remove a symbol file added via add-symbol-file. The file to remove
2408 can be identified by its filename or by an address that lies within
2409 the boundaries of this symbol file in memory.
2412 info exceptions REGEXP
2413 Display the list of Ada exceptions defined in the program being
2414 debugged. If provided, only the exceptions whose names match REGEXP
2419 set debug symfile off|on
2421 Control display of debugging info regarding reading symbol files and
2422 symbol tables within those files
2424 set print raw frame-arguments
2425 show print raw frame-arguments
2426 Set/show whether to print frame arguments in raw mode,
2427 disregarding any defined pretty-printers.
2429 set remote trace-status-packet
2430 show remote trace-status-packet
2431 Set/show the use of remote protocol qTStatus packet.
2435 Control display of debugging messages related to Nios II targets.
2439 Control whether target-assisted range stepping is enabled.
2441 set startup-with-shell
2442 show startup-with-shell
2443 Specifies whether Unix child processes are started via a shell or
2448 Use the target memory cache for accesses to the code segment. This
2449 improves performance of remote debugging (particularly disassembly).
2451 * You can now use a literal value 'unlimited' for options that
2452 interpret 0 or -1 as meaning "unlimited". E.g., "set
2453 trace-buffer-size unlimited" is now an alias for "set
2454 trace-buffer-size -1" and "set height unlimited" is now an alias for
2457 * The "set debug symtab-create" debugging option of GDB has been changed to
2458 accept a verbosity level. 0 means "off", 1 provides basic debugging
2459 output, and values of 2 or greater provides more verbose output.
2461 * New command-line options
2463 Display the details of GDB configure-time options.
2465 * The command 'tsave' can now support new option '-ctf' to save trace
2466 buffer in Common Trace Format.
2468 * Newly installed $prefix/bin/gcore acts as a shell interface for the
2471 * GDB now implements the C++ 'typeid' operator.
2473 * The new convenience variable $_exception holds the exception being
2474 thrown or caught at an exception-related catchpoint.
2476 * The exception-related catchpoints, like "catch throw", now accept a
2477 regular expression which can be used to filter exceptions by type.
2479 * The new convenience variable $_exitsignal is automatically set to
2480 the terminating signal number when the program being debugged dies
2481 due to an uncaught signal.
2485 ** All MI commands now accept an optional "--language" option.
2486 Support for this feature can be verified by using the "-list-features"
2487 command, which should contain "language-option".
2489 ** The new command -info-gdb-mi-command allows the user to determine
2490 whether a GDB/MI command is supported or not.
2492 ** The "^error" result record returned when trying to execute an undefined
2493 GDB/MI command now provides a variable named "code" whose content is the
2494 "undefined-command" error code. Support for this feature can be verified
2495 by using the "-list-features" command, which should contain
2496 "undefined-command-error-code".
2498 ** The -trace-save MI command can optionally save trace buffer in Common
2501 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2503 ** The command -data-list-register-values now accepts an optional
2504 "--skip-unavailable" option. When used, only the available registers
2507 ** The new command -trace-frame-collected dumps collected variables,
2508 computed expressions, tvars, memory and registers in a traceframe.
2510 ** The commands -stack-list-locals, -stack-list-arguments and
2511 -stack-list-variables now accept an option "--skip-unavailable".
2512 When used, only the available locals or arguments are displayed.
2514 ** The -exec-run command now accepts an optional "--start" option.
2515 When used, the command follows the same semantics as the "start"
2516 command, stopping the program's execution at the start of its
2517 main subprogram. Support for this feature can be verified using
2518 the "-list-features" command, which should contain
2519 "exec-run-start-option".
2521 ** The new commands -catch-assert and -catch-exceptions insert
2522 catchpoints stopping the program when Ada exceptions are raised.
2524 ** The new command -info-ada-exceptions provides the equivalent of
2525 the new "info exceptions" command.
2527 * New system-wide configuration scripts
2528 A GDB installation now provides scripts suitable for use as system-wide
2529 configuration scripts for the following systems:
2533 * GDB now supports target-assigned range stepping with remote targets.
2534 This improves the performance of stepping source lines by reducing
2535 the number of control packets from/to GDB. See "New remote packets"
2538 * GDB now understands the element 'tvar' in the XML traceframe info.
2539 It has the id of the collected trace state variables.
2541 * On S/390 targets that provide the transactional-execution feature,
2542 the program interruption transaction diagnostic block (TDB) is now
2543 represented as a number of additional "registers" in GDB.
2545 * New remote packets
2549 The vCont packet supports a new 'r' action, that tells the remote
2550 stub to step through an address range itself, without GDB
2551 involvemement at each single-step.
2553 qXfer:libraries-svr4:read's annex
2554 The previously unused annex of the qXfer:libraries-svr4:read packet
2555 is now used to support passing an argument list. The remote stub
2556 reports support for this argument list to GDB's qSupported query.
2557 The defined arguments are "start" and "prev", used to reduce work
2558 necessary for library list updating, resulting in significant
2561 * New features in the GDB remote stub, GDBserver
2563 ** GDBserver now supports target-assisted range stepping. Currently
2564 enabled on x86/x86_64 GNU/Linux targets.
2566 ** GDBserver now adds element 'tvar' in the XML in the reply to
2567 'qXfer:traceframe-info:read'. It has the id of the collected
2568 trace state variables.
2570 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2573 * New 'z' formatter for printing and examining memory, this displays the
2574 value as hexadecimal zero padded on the left to the size of the type.
2576 * GDB can now use Windows x64 unwinding data.
2578 * The "set remotebaud" command has been replaced by "set serial baud".
2579 Similarly, "show remotebaud" has been replaced by "show serial baud".
2580 The "set remotebaud" and "show remotebaud" commands are still available
2581 to provide backward compatibility with older versions of GDB.
2583 *** Changes in GDB 7.6
2585 * Target record has been renamed to record-full.
2586 Record/replay is now enabled with the "record full" command.
2587 This also affects settings that are associated with full record/replay
2588 that have been moved from "set/show record" to "set/show record full":
2590 set|show record full insn-number-max
2591 set|show record full stop-at-limit
2592 set|show record full memory-query
2594 * A new record target "record-btrace" has been added. The new target
2595 uses hardware support to record the control-flow of a process. It
2596 does not support replaying the execution, but it implements the
2597 below new commands for investigating the recorded execution log.
2598 This new recording method can be enabled using:
2602 The "record-btrace" target is only available on Intel Atom processors
2603 and requires a Linux kernel 2.6.32 or later.
2605 * Two new commands have been added for record/replay to give information
2606 about the recorded execution without having to replay the execution.
2607 The commands are only supported by "record btrace".
2609 record instruction-history prints the execution history at
2610 instruction granularity
2612 record function-call-history prints the execution history at
2613 function granularity
2615 * New native configurations
2617 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2618 FreeBSD/powerpc powerpc*-*-freebsd
2619 x86_64/Cygwin x86_64-*-cygwin*
2620 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2624 ARM AArch64 aarch64*-*-elf
2625 ARM AArch64 GNU/Linux aarch64*-*-linux
2626 Lynx 178 PowerPC powerpc-*-lynx*178
2627 x86_64/Cygwin x86_64-*-cygwin*
2628 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2630 * If the configured location of system.gdbinit file (as given by the
2631 --with-system-gdbinit option at configure time) is in the
2632 data-directory (as specified by --with-gdb-datadir at configure
2633 time) or in one of its subdirectories, then GDB will look for the
2634 system-wide init file in the directory specified by the
2635 --data-directory command-line option.
2637 * New command line options:
2639 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2640 other initialization files, unlike -nx which disables all of them.
2642 * Removed command line options
2644 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2647 * The 'ptype' and 'whatis' commands now accept an argument to control
2650 * 'info proc' now works on some core files.
2654 ** Vectors can be created with gdb.Type.vector.
2656 ** Python's atexit.register now works in GDB.
2658 ** Types can be pretty-printed via a Python API.
2660 ** Python 3 is now supported (in addition to Python 2.4 or later)
2662 ** New class gdb.Architecture exposes GDB's internal representation
2663 of architecture in the Python API.
2665 ** New method Frame.architecture returns the gdb.Architecture object
2666 corresponding to the frame's architecture.
2668 * New Python-based convenience functions:
2670 ** $_memeq(buf1, buf2, length)
2671 ** $_streq(str1, str2)
2673 ** $_regex(str, regex)
2675 * The 'cd' command now defaults to using '~' (the home directory) if not
2678 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2679 default for GCC since November 2000.
2681 * The command 'forward-search' can now be abbreviated as 'fo'.
2683 * The command 'info tracepoints' can now display 'installed on target'
2684 or 'not installed on target' for each non-pending location of tracepoint.
2686 * New configure options
2688 --enable-libmcheck/--disable-libmcheck
2689 By default, development versions are built with -lmcheck on hosts
2690 that support it, in order to help track memory corruption issues.
2691 Release versions, on the other hand, are built without -lmcheck
2692 by default. The --enable-libmcheck/--disable-libmcheck configure
2693 options allow the user to override that default.
2694 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2695 This configure option allows the user to build GDB with
2696 libbabeltrace using which GDB can read Common Trace Format data.
2698 * New commands (for set/show, see "New options" below)
2701 Catch signals. This is similar to "handle", but allows commands and
2702 conditions to be attached.
2705 List the BFDs known to GDB.
2707 python-interactive [command]
2709 Start a Python interactive prompt, or evaluate the optional command
2710 and print the result of expressions.
2713 "py" is a new alias for "python".
2715 enable type-printer [name]...
2716 disable type-printer [name]...
2717 Enable or disable type printers.
2721 ** For the Renesas Super-H architecture, the "regs" command has been removed
2722 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2727 set print type methods (on|off)
2728 show print type methods
2729 Control whether method declarations are displayed by "ptype".
2730 The default is to show them.
2732 set print type typedefs (on|off)
2733 show print type typedefs
2734 Control whether typedef definitions are displayed by "ptype".
2735 The default is to show them.
2737 set filename-display basename|relative|absolute
2738 show filename-display
2739 Control the way in which filenames is displayed.
2740 The default is "relative", which preserves previous behavior.
2742 set trace-buffer-size
2743 show trace-buffer-size
2744 Request target to change the size of trace buffer.
2746 set remote trace-buffer-size-packet auto|on|off
2747 show remote trace-buffer-size-packet
2748 Control the use of the remote protocol `QTBuffer:size' packet.
2752 Control display of debugging messages related to ARM AArch64.
2755 set debug coff-pe-read
2756 show debug coff-pe-read
2757 Control display of debugging messages related to reading of COFF/PE
2762 Control display of debugging messages related to Mach-O symbols
2765 set debug notification
2766 show debug notification
2767 Control display of debugging info for async remote notification.
2771 ** Command parameter changes are now notified using new async record
2772 "=cmd-param-changed".
2773 ** Trace frame changes caused by command "tfind" are now notified using
2774 new async record "=traceframe-changed".
2775 ** The creation, deletion and modification of trace state variables
2776 are now notified using new async records "=tsv-created",
2777 "=tsv-deleted" and "=tsv-modified".
2778 ** The start and stop of process record are now notified using new
2779 async record "=record-started" and "=record-stopped".
2780 ** Memory changes are now notified using new async record
2782 ** The data-disassemble command response will include a "fullname" field
2783 containing the absolute file name when source has been requested.
2784 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
2785 command, to allow pattern filling of memory areas.
2786 ** New commands "-catch-load"/"-catch-unload" added for intercepting
2787 library load/unload events.
2788 ** The response to breakpoint commands and breakpoint async records
2789 includes an "installed" field containing a boolean state about each
2790 non-pending tracepoint location is whether installed on target or not.
2791 ** Output of the "-trace-status" command includes a "trace-file" field
2792 containing the name of the trace file being examined. This field is
2793 optional, and only present when examining a trace file.
2794 ** The "fullname" field is now always present along with the "file" field,
2795 even if the file cannot be found by GDB.
2797 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
2798 You must have the LZMA library available when configuring GDB for this
2799 feature to be enabled. For more information, see:
2800 http://fedoraproject.org/wiki/Features/MiniDebugInfo
2802 * New remote packets
2805 Set the size of trace buffer. The remote stub reports support for this
2806 packet to gdb's qSupported query.
2809 Enable Branch Trace Store (BTS)-based branch tracing for the current
2810 thread. The remote stub reports support for this packet to gdb's
2814 Disable branch tracing for the current thread. The remote stub reports
2815 support for this packet to gdb's qSupported query.
2818 Read the traced branches for the current thread. The remote stub
2819 reports support for this packet to gdb's qSupported query.
2821 *** Changes in GDB 7.5
2823 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2824 for more x32 ABI info.
2826 * GDB now supports access to MIPS DSP registers on Linux targets.
2828 * GDB now supports debugging microMIPS binaries.
2830 * The "info os" command on GNU/Linux can now display information on
2831 several new classes of objects managed by the operating system:
2832 "info os procgroups" lists process groups
2833 "info os files" lists file descriptors
2834 "info os sockets" lists internet-domain sockets
2835 "info os shm" lists shared-memory regions
2836 "info os semaphores" lists semaphores
2837 "info os msg" lists message queues
2838 "info os modules" lists loaded kernel modules
2840 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2841 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2842 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2843 options and inspect the probe arguments using the new $_probe_arg family
2844 of convenience variables. You can obtain more information about SystemTap
2845 in <http://sourceware.org/systemtap/>.
2847 * GDB now supports reversible debugging on ARM, it allows you to
2848 debug basic ARM and THUMB instructions, and provides
2849 record/replay support.
2851 * The option "symbol-reloading" has been deleted as it is no longer used.
2855 ** GDB commands implemented in Python can now be put in command class
2858 ** The "maint set python print-stack on|off" is now deleted.
2860 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
2861 apply "flag enum"-style pretty-printing to any enum.
2863 ** gdb.lookup_symbol can now work when there is no current frame.
2865 ** gdb.Symbol now has a 'line' attribute, holding the line number in
2866 the source at which the symbol was defined.
2868 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
2869 method 'value'. The former indicates whether the symbol needs a
2870 frame in order to compute its value, and the latter computes the
2873 ** A new method 'referenced_value' on gdb.Value objects which can
2874 dereference pointer as well as C++ reference values.
2876 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
2877 which return the global and static blocks (as gdb.Block objects),
2878 of the underlying symbol table, respectively.
2880 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2881 object associated with a PC value.
2883 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2884 of the address range occupied by code for the current source line.
2886 * Go language support.
2887 GDB now supports debugging programs written in the Go programming
2890 * GDBserver now supports stdio connections.
2891 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2893 * The binary "gdbtui" can no longer be built or installed.
2894 Use "gdb -tui" instead.
2896 * GDB will now print "flag" enums specially. A flag enum is one where
2897 all the enumerator values have no bits in common when pairwise
2898 "and"ed. When printing a value whose type is a flag enum, GDB will
2899 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2900 (gdb) print (enum E) 3
2903 * The filename part of a linespec will now match trailing components
2904 of a source file name. For example, "break gcc/expr.c:1000" will
2905 now set a breakpoint in build/gcc/expr.c, but not
2906 build/libcpp/expr.c.
2908 * The "info proc" and "generate-core-file" commands will now also
2909 work on remote targets connected to GDBserver on Linux.
2911 * The command "info catch" has been removed. It has been disabled
2912 since December 2007.
2914 * The "catch exception" and "catch assert" commands now accept
2915 a condition at the end of the command, much like the "break"
2916 command does. For instance:
2918 (gdb) catch exception Constraint_Error if Barrier = True
2920 Previously, it was possible to add a condition to such catchpoints,
2921 but it had to be done as a second step, after the catchpoint had been
2922 created, using the "condition" command.
2924 * The "info static-tracepoint-marker" command will now also work on
2925 native Linux targets with in-process agent.
2927 * GDB can now set breakpoints on inlined functions.
2929 * The .gdb_index section has been updated to include symbols for
2930 inlined functions. GDB will ignore older .gdb_index sections by
2931 default, which could cause symbol files to be loaded more slowly
2932 until their .gdb_index sections can be recreated. The new command
2933 "set use-deprecated-index-sections on" will cause GDB to use any older
2934 .gdb_index sections it finds. This will restore performance, but the
2935 ability to set breakpoints on inlined functions will be lost in symbol
2936 files with older .gdb_index sections.
2938 The .gdb_index section has also been updated to record more information
2939 about each symbol. This speeds up the "info variables", "info functions"
2940 and "info types" commands when used with programs having the .gdb_index
2941 section, as well as speeding up debugging with shared libraries using
2942 the .gdb_index section.
2944 * Ada support for GDB/MI Variable Objects has been added.
2946 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2951 ** New command -info-os is the MI equivalent of "info os".
2953 ** Output logs ("set logging" and related) now include MI output.
2957 ** "set use-deprecated-index-sections on|off"
2958 "show use-deprecated-index-sections on|off"
2959 Controls the use of deprecated .gdb_index sections.
2961 ** "catch load" and "catch unload" can be used to stop when a shared
2962 library is loaded or unloaded, respectively.
2964 ** "enable count" can be used to auto-disable a breakpoint after
2967 ** "info vtbl" can be used to show the virtual method tables for
2968 C++ and Java objects.
2970 ** "explore" and its sub commands "explore value" and "explore type"
2971 can be used to recursively explore values and types of
2972 expressions. These commands are available only if GDB is
2973 configured with '--with-python'.
2975 ** "info auto-load" shows status of all kinds of auto-loaded files,
2976 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2977 sequences of commands files, "info auto-load python-scripts"
2978 shows status of auto-loading Python script files,
2979 "info auto-load local-gdbinit" shows status of loading init file
2980 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2981 status of inferior specific thread debugging shared library loading.
2983 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2984 and "show auto-load-scripts" commands have been deprecated, use their
2985 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2986 and "show auto-load python-scripts" counterparts instead.
2988 ** "dprintf location,format,args..." creates a dynamic printf, which
2989 is basically a breakpoint that does a printf and immediately
2990 resumes your program's execution, so it is like a printf that you
2991 can insert dynamically at runtime instead of at compiletime.
2993 ** "set print symbol"
2995 Controls whether GDB attempts to display the symbol, if any,
2996 corresponding to addresses it prints. This defaults to "on", but
2997 you can set it to "off" to restore GDB's previous behavior.
2999 * Deprecated commands
3001 ** For the Renesas Super-H architecture, the "regs" command has been
3002 deprecated, and "info all-registers" should be used instead.
3006 Renesas RL78 rl78-*-elf
3007 HP OpenVMS ia64 ia64-hp-openvms*
3009 * GDBserver supports evaluation of breakpoint conditions. When
3010 support is advertised by GDBserver, GDB may be told to send the
3011 breakpoint conditions in bytecode form to GDBserver. GDBserver
3012 will only report the breakpoint trigger to GDB when its condition
3017 set mips compression
3018 show mips compression
3019 Select the compressed ISA encoding used in functions that have no symbol
3020 information available. The encoding can be set to either of:
3023 and is updated automatically from ELF file flags if available.
3025 set breakpoint condition-evaluation
3026 show breakpoint condition-evaluation
3027 Control whether breakpoint conditions are evaluated by GDB ("host") or by
3028 GDBserver ("target"). Default option "auto" chooses the most efficient
3030 This option can improve debugger efficiency depending on the speed of the
3034 Disable auto-loading globally.
3037 Show auto-loading setting of all kinds of auto-loaded files.
3039 set auto-load gdb-scripts on|off
3040 show auto-load gdb-scripts
3041 Control auto-loading of GDB canned sequences of commands files.
3043 set auto-load python-scripts on|off
3044 show auto-load python-scripts
3045 Control auto-loading of Python script files.
3047 set auto-load local-gdbinit on|off
3048 show auto-load local-gdbinit
3049 Control loading of init file (.gdbinit) from current directory.
3051 set auto-load libthread-db on|off
3052 show auto-load libthread-db
3053 Control auto-loading of inferior specific thread debugging shared library.
3055 set auto-load scripts-directory <dir1>[:<dir2>...]
3056 show auto-load scripts-directory
3057 Set a list of directories from which to load auto-loaded scripts.
3058 Automatically loaded Python scripts and GDB scripts are located in one
3059 of the directories listed by this option.
3060 The delimiter (':' above) may differ according to the host platform.
3062 set auto-load safe-path <dir1>[:<dir2>...]
3063 show auto-load safe-path
3064 Set a list of directories from which it is safe to auto-load files.
3065 The delimiter (':' above) may differ according to the host platform.
3067 set debug auto-load on|off
3068 show debug auto-load
3069 Control display of debugging info for auto-loading the files above.
3071 set dprintf-style gdb|call|agent
3073 Control the way in which a dynamic printf is performed; "gdb"
3074 requests a GDB printf command, while "call" causes dprintf to call a
3075 function in the inferior. "agent" requests that the target agent
3076 (such as GDBserver) do the printing.
3078 set dprintf-function <expr>
3079 show dprintf-function
3080 set dprintf-channel <expr>
3081 show dprintf-channel
3082 Set the function and optional first argument to the call when using
3083 the "call" style of dynamic printf.
3085 set disconnected-dprintf on|off
3086 show disconnected-dprintf
3087 Control whether agent-style dynamic printfs continue to be in effect
3088 after GDB disconnects.
3090 * New configure options
3092 --with-auto-load-dir
3093 Configure default value for the 'set auto-load scripts-directory'
3094 setting above. It defaults to '$debugdir:$datadir/auto-load',
3095 $debugdir representing global debugging info directories (available
3096 via 'show debug-file-directory') and $datadir representing GDB's data
3097 directory (available via 'show data-directory').
3099 --with-auto-load-safe-path
3100 Configure default value for the 'set auto-load safe-path' setting
3101 above. It defaults to the --with-auto-load-dir setting.
3103 --without-auto-load-safe-path
3104 Set 'set auto-load safe-path' to '/', effectively disabling this
3107 * New remote packets
3109 z0/z1 conditional breakpoints extension
3111 The z0/z1 breakpoint insertion packets have been extended to carry
3112 a list of conditional expressions over to the remote stub depending on the
3113 condition evaluation mode. The use of this extension can be controlled
3114 via the "set remote conditional-breakpoints-packet" command.
3118 Specify the signals which the remote stub may pass to the debugged
3119 program without GDB involvement.
3121 * New command line options
3123 --init-command=FILE, -ix Like --command, -x but execute it
3124 before loading inferior.
3125 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
3126 execute it before loading inferior.
3128 *** Changes in GDB 7.4
3130 * GDB now handles ambiguous linespecs more consistently; the existing
3131 FILE:LINE support has been expanded to other types of linespecs. A
3132 breakpoint will now be set on all matching locations in all
3133 inferiors, and locations will be added or removed according to
3136 * GDB now allows you to skip uninteresting functions and files when
3137 stepping with the "skip function" and "skip file" commands.
3139 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
3140 and "show remote hardware-watchpoint-length-limit". These allows to
3141 set or show the maximum length limit (in bytes) of a remote
3142 target hardware watchpoint.
3144 This allows e.g. to use "unlimited" hardware watchpoints with the
3145 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
3146 watchpoints are slower than real hardware watchpoints but are
3147 significantly faster than gdb software watchpoints.
3151 ** The register_pretty_printer function in module gdb.printing now takes
3152 an optional `replace' argument. If True, the new printer replaces any
3155 ** The "maint set python print-stack on|off" command has been
3156 deprecated and will be deleted in GDB 7.5.
3157 A new command: "set python print-stack none|full|message" has
3158 replaced it. Additionally, the default for "print-stack" is
3159 now "message", which just prints the error message without
3162 ** A prompt substitution hook (prompt_hook) is now available to the
3165 ** A new Python module, gdb.prompt has been added to the GDB Python
3166 modules library. This module provides functionality for
3167 escape sequences in prompts (used by set/show
3168 extended-prompt). These escape sequences are replaced by their
3169 corresponding value.
3171 ** Python commands and convenience-functions located in
3172 'data-directory'/python/gdb/command and
3173 'data-directory'/python/gdb/function are now automatically loaded
3176 ** Blocks now provide four new attributes. global_block and
3177 static_block will return the global and static blocks
3178 respectively. is_static and is_global are boolean attributes
3179 that indicate if the block is one of those two types.
3181 ** Symbols now provide the "type" attribute, the type of the symbol.
3183 ** The "gdb.breakpoint" function has been deprecated in favor of
3186 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
3187 of a function. This class is based on the "finish" command
3188 available in the CLI.
3190 ** Type objects for struct and union types now allow access to
3191 the fields using standard Python dictionary (mapping) methods.
3192 For example, "some_type['myfield']" now works, as does
3193 "some_type.items()".
3195 ** A new event "gdb.new_objfile" has been added, triggered by loading a
3198 ** A new function, "deep_items" has been added to the gdb.types
3199 module in the GDB Python modules library. This function returns
3200 an iterator over the fields of a struct or union type. Unlike
3201 the standard Python "iteritems" method, it will recursively traverse
3202 any anonymous fields.
3206 ** "*stopped" events can report several new "reason"s, such as
3209 ** Breakpoint changes are now notified using new async records, like
3210 "=breakpoint-modified".
3212 ** New command -ada-task-info.
3214 * libthread-db-search-path now supports two special values: $sdir and $pdir.
3215 $sdir specifies the default system locations of shared libraries.
3216 $pdir specifies the directory where the libpthread used by the application
3219 GDB no longer looks in $sdir and $pdir after it has searched the directories
3220 mentioned in libthread-db-search-path. If you want to search those
3221 directories, they must be specified in libthread-db-search-path.
3222 The default value of libthread-db-search-path on GNU/Linux and Solaris
3223 systems is now "$sdir:$pdir".
3225 $pdir is not supported by gdbserver, it is currently ignored.
3226 $sdir is supported by gdbserver.
3228 * New configure option --with-iconv-bin.
3229 When using the internationalization support like the one in the GNU C
3230 library, GDB will invoke the "iconv" program to get a list of supported
3231 character sets. If this program lives in a non-standard location, one can
3232 use this option to specify where to find it.
3234 * When natively debugging programs on PowerPC BookE processors running
3235 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
3236 watchpoints, which specify a mask in addition to an address to watch.
3237 The mask specifies that some bits of an address (the bits which are
3238 reset in the mask) should be ignored when matching the address accessed
3239 by the inferior against the watchpoint address. See the "PowerPC Embedded"
3240 section in the user manual for more details.
3242 * The new option --once causes GDBserver to stop listening for connections once
3243 the first connection is made. The listening port used by GDBserver will
3244 become available after that.
3246 * New commands "info macros" and "alias" have been added.
3248 * New function parameters suffix @entry specifies value of function parameter
3249 at the time the function got called. Entry values are available only since
3255 "!" is now an alias of the "shell" command.
3256 Note that no space is needed between "!" and SHELL COMMAND.
3260 watch EXPRESSION mask MASK_VALUE
3261 The watch command now supports the mask argument which allows creation
3262 of masked watchpoints, if the current architecture supports this feature.
3264 info auto-load-scripts [REGEXP]
3265 This command was formerly named "maintenance print section-scripts".
3266 It is now generally useful and is no longer a maintenance-only command.
3268 info macro [-all] [--] MACRO
3269 The info macro command has new options `-all' and `--'. The first for
3270 printing all definitions of a macro. The second for explicitly specifying
3271 the end of arguments and the beginning of the macro name in case the macro
3272 name starts with a hyphen.
3274 collect[/s] EXPRESSIONS
3275 The tracepoint collect command now takes an optional modifier "/s"
3276 that directs it to dereference pointer-to-character types and
3277 collect the bytes of memory up to a zero byte. The behavior is
3278 similar to what you see when you use the regular print command on a
3279 string. An optional integer following the "/s" sets a bound on the
3280 number of bytes that will be collected.
3283 The trace start command now interprets any supplied arguments as a
3284 note to be recorded with the trace run, with an effect similar to
3285 setting the variable trace-notes.
3288 The trace stop command now interprets any arguments as a note to be
3289 mentioned along with the tstatus report that the trace was stopped
3290 with a command. The effect is similar to setting the variable
3293 * Tracepoints can now be enabled and disabled at any time after a trace
3294 experiment has been started using the standard "enable" and "disable"
3295 commands. It is now possible to start a trace experiment with no enabled
3296 tracepoints; GDB will display a warning, but will allow the experiment to
3297 begin, assuming that tracepoints will be enabled as needed while the trace
3300 * Fast tracepoints on 32-bit x86-architectures can now be placed at
3301 locations with 4-byte instructions, when they were previously
3302 limited to locations with instructions of 5 bytes or longer.
3306 set debug dwarf2-read
3307 show debug dwarf2-read
3308 Turns on or off display of debugging messages related to reading
3309 DWARF debug info. The default is off.
3311 set debug symtab-create
3312 show debug symtab-create
3313 Turns on or off display of debugging messages related to symbol table
3314 creation. The default is off.
3317 show extended-prompt
3318 Set the GDB prompt, and allow escape sequences to be inserted to
3319 display miscellaneous information (see 'help set extended-prompt'
3320 for the list of sequences). This prompt (and any information
3321 accessed through the escape sequences) is updated every time the
3322 prompt is displayed.
3324 set print entry-values (both|compact|default|if-needed|no|only|preferred)
3325 show print entry-values
3326 Set printing of frame argument values at function entry. In some cases
3327 GDB can determine the value of function argument which was passed by the
3328 function caller, even if the value was modified inside the called function.
3330 set debug entry-values
3331 show debug entry-values
3332 Control display of debugging info for determining frame argument values at
3333 function entry and virtual tail call frames.
3335 set basenames-may-differ
3336 show basenames-may-differ
3337 Set whether a source file may have multiple base names.
3338 (A "base name" is the name of a file with the directory part removed.
3339 Example: The base name of "/home/user/hello.c" is "hello.c".)
3340 If set, GDB will canonicalize file names (e.g., expand symlinks)
3341 before comparing them. Canonicalization is an expensive operation,
3342 but it allows the same file be known by more than one base name.
3343 If not set (the default), all source files are assumed to have just
3344 one base name, and gdb will do file name comparisons more efficiently.
3350 Set a user name and notes for the current and any future trace runs.
3351 This is useful for long-running and/or disconnected traces, to
3352 inform others (or yourself) as to who is running the trace, supply
3353 contact information, or otherwise explain what is going on.
3355 set trace-stop-notes
3356 show trace-stop-notes
3357 Set a note attached to the trace run, that is displayed when the
3358 trace has been stopped by a tstop command. This is useful for
3359 instance as an explanation, if you are stopping a trace run that was
3360 started by someone else.
3362 * New remote packets
3366 Dynamically enable a tracepoint in a started trace experiment.
3370 Dynamically disable a tracepoint in a started trace experiment.
3374 Set the user and notes of the trace run.
3378 Query the current status of a tracepoint.
3382 Query the minimum length of instruction at which a fast tracepoint may
3385 * Dcache size (number of lines) and line-size are now runtime-configurable
3386 via "set dcache line" and "set dcache line-size" commands.
3390 Texas Instruments TMS320C6x tic6x-*-*
3394 Renesas RL78 rl78-*-elf
3396 *** Changes in GDB 7.3.1
3398 * The build failure for NetBSD and OpenBSD targets have now been fixed.
3400 *** Changes in GDB 7.3
3402 * GDB has a new command: "thread find [REGEXP]".
3403 It finds the thread id whose name, target id, or thread extra info
3404 matches the given regular expression.
3406 * The "catch syscall" command now works on mips*-linux* targets.
3408 * The -data-disassemble MI command now supports modes 2 and 3 for
3409 dumping the instruction opcodes.
3411 * New command line options
3413 -data-directory DIR Specify DIR as the "data-directory".
3414 This is mostly for testing purposes.
3416 * The "maint set python auto-load on|off" command has been renamed to
3417 "set auto-load-scripts on|off".
3419 * GDB has a new command: "set directories".
3420 It is like the "dir" command except that it replaces the
3421 source path list instead of augmenting it.
3423 * GDB now understands thread names.
3425 On GNU/Linux, "info threads" will display the thread name as set by
3426 prctl or pthread_setname_np.
3428 There is also a new command, "thread name", which can be used to
3429 assign a name internally for GDB to display.
3432 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
3433 has been integrated into GDB.
3437 ** The function gdb.Write now accepts an optional keyword 'stream'.
3438 This keyword, when provided, will direct the output to either
3439 stdout, stderr, or GDB's logging output.
3441 ** Parameters can now be be sub-classed in Python, and in particular
3442 you may implement the get_set_doc and get_show_doc functions.
3443 This improves how Parameter set/show documentation is processed
3444 and allows for more dynamic content.
3446 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
3447 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
3448 have an is_valid method.
3450 ** Breakpoints can now be sub-classed in Python, and in particular
3451 you may implement a 'stop' function that is executed each time
3452 the inferior reaches that breakpoint.
3454 ** New function gdb.lookup_global_symbol looks up a global symbol.
3456 ** GDB values in Python are now callable if the value represents a
3457 function. For example, if 'some_value' represents a function that
3458 takes two integer parameters and returns a value, you can call
3459 that function like so:
3461 result = some_value (10,20)
3463 ** Module gdb.types has been added.
3464 It contains a collection of utilities for working with gdb.Types objects:
3465 get_basic_type, has_field, make_enum_dict.
3467 ** Module gdb.printing has been added.
3468 It contains utilities for writing and registering pretty-printers.
3469 New classes: PrettyPrinter, SubPrettyPrinter,
3470 RegexpCollectionPrettyPrinter.
3471 New function: register_pretty_printer.
3473 ** New commands "info pretty-printers", "enable pretty-printer" and
3474 "disable pretty-printer" have been added.
3476 ** gdb.parameter("directories") is now available.
3478 ** New function gdb.newest_frame returns the newest frame in the
3481 ** The gdb.InferiorThread class has a new "name" attribute. This
3482 holds the thread's name.
3484 ** Python Support for Inferior events.
3485 Python scripts can add observers to be notified of events
3486 occurring in the process being debugged.
3487 The following events are currently supported:
3488 - gdb.events.cont Continue event.
3489 - gdb.events.exited Inferior exited event.
3490 - gdb.events.stop Signal received, and Breakpoint hit events.
3494 ** GDB now puts template parameters in scope when debugging in an
3495 instantiation. For example, if you have:
3497 template<int X> int func (void) { return X; }
3499 then if you step into func<5>, "print X" will show "5". This
3500 feature requires proper debuginfo support from the compiler; it
3501 was added to GCC 4.5.
3503 ** The motion commands "next", "finish", "until", and "advance" now
3504 work better when exceptions are thrown. In particular, GDB will
3505 no longer lose control of the inferior; instead, the GDB will
3506 stop the inferior at the point at which the exception is caught.
3507 This functionality requires a change in the exception handling
3508 code that was introduced in GCC 4.5.
3510 * GDB now follows GCC's rules on accessing volatile objects when
3511 reading or writing target state during expression evaluation.
3512 One notable difference to prior behavior is that "print x = 0"
3513 no longer generates a read of x; the value of the assignment is
3514 now always taken directly from the value being assigned.
3516 * GDB now has some support for using labels in the program's source in
3517 linespecs. For instance, you can use "advance label" to continue
3518 execution to a label.
3520 * GDB now has support for reading and writing a new .gdb_index
3521 section. This section holds a fast index of DWARF debugging
3522 information and can be used to greatly speed up GDB startup and
3523 operation. See the documentation for `save gdb-index' for details.
3525 * The "watch" command now accepts an optional "-location" argument.
3526 When used, this causes GDB to watch the memory referred to by the
3527 expression. Such a watchpoint is never deleted due to it going out
3530 * GDB now supports thread debugging of core dumps on GNU/Linux.
3532 GDB now activates thread debugging using the libthread_db library
3533 when debugging GNU/Linux core dumps, similarly to when debugging
3534 live processes. As a result, when debugging a core dump file, GDB
3535 is now able to display pthread_t ids of threads. For example, "info
3536 threads" shows the same output as when debugging the process when it
3537 was live. In earlier releases, you'd see something like this:
3540 * 1 LWP 6780 main () at main.c:10
3542 While now you see this:
3545 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3547 It is also now possible to inspect TLS variables when debugging core
3550 When debugging a core dump generated on a machine other than the one
3551 used to run GDB, you may need to point GDB at the correct
3552 libthread_db library with the "set libthread-db-search-path"
3553 command. See the user manual for more details on this command.
3555 * When natively debugging programs on PowerPC BookE processors running
3556 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3557 which stop execution of the inferior whenever it executes an instruction
3558 at any address within the specified range. See the "PowerPC Embedded"
3559 section in the user manual for more details.
3561 * New features in the GDB remote stub, GDBserver
3563 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3564 and i686 LynxOS (version 5.x).
3566 ** GDBserver is now supported on Blackfin Linux.
3568 * New native configurations
3570 ia64 HP-UX ia64-*-hpux*
3574 Analog Devices, Inc. Blackfin Processor bfin-*
3576 * Ada task switching is now supported on sparc-elf targets when
3577 debugging a program using the Ravenscar Profile. For more information,
3578 see the "Tasking Support when using the Ravenscar Profile" section
3579 in the GDB user manual.
3581 * Guile support was removed.
3583 * New features in the GNU simulator
3585 ** The --map-info flag lists all known core mappings.
3587 ** CFI flashes may be simulated via the "cfi" device.
3589 *** Changes in GDB 7.2
3591 * Shared library support for remote targets by default
3593 When GDB is configured for a generic, non-OS specific target, like
3594 for example, --target=arm-eabi or one of the many *-*-elf targets,
3595 GDB now queries remote stubs for loaded shared libraries using the
3596 `qXfer:libraries:read' packet. Previously, shared library support
3597 was always disabled for such configurations.
3601 ** Argument Dependent Lookup (ADL)
3603 In C++ ADL lookup directs function search to the namespaces of its
3604 arguments even if the namespace has not been imported.
3614 Here the compiler will search for `foo' in the namespace of 'b'
3615 and find A::foo. GDB now supports this. This construct is commonly
3616 used in the Standard Template Library for operators.
3618 ** Improved User Defined Operator Support
3620 In addition to member operators, GDB now supports lookup of operators
3621 defined in a namespace and imported with a `using' directive, operators
3622 defined in the global scope, operators imported implicitly from an
3623 anonymous namespace, and the ADL operators mentioned in the previous
3625 GDB now also supports proper overload resolution for all the previously
3626 mentioned flavors of operators.
3628 ** static const class members
3630 Printing of static const class members that are initialized in the
3631 class definition has been fixed.
3633 * Windows Thread Information Block access.
3635 On Windows targets, GDB now supports displaying the Windows Thread
3636 Information Block (TIB) structure. This structure is visible either
3637 by using the new command `info w32 thread-information-block' or, by
3638 dereferencing the new convenience variable named `$_tlb', a
3639 thread-specific pointer to the TIB. This feature is also supported
3640 when remote debugging using GDBserver.
3642 * Static tracepoints
3644 Static tracepoints are calls in the user program into a tracing
3645 library. One such library is a port of the LTTng kernel tracer to
3646 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3647 When debugging with GDBserver, GDB now supports combining the GDB
3648 tracepoint machinery with such libraries. For example: the user can
3649 use GDB to probe a static tracepoint marker (a call from the user
3650 program into the tracing library) with the new "strace" command (see
3651 "New commands" below). This creates a "static tracepoint" in the
3652 breakpoint list, that can be manipulated with the same feature set
3653 as fast and regular tracepoints. E.g., collect registers, local and
3654 global variables, collect trace state variables, and define
3655 tracepoint conditions. In addition, the user can collect extra
3656 static tracepoint marker specific data, by collecting the new
3657 $_sdata internal variable. When analyzing the trace buffer, you can
3658 inspect $_sdata like any other variable available to GDB. For more
3659 information, see the "Tracepoints" chapter in GDB user manual. New
3660 remote packets have been defined to support static tracepoints, see
3661 the "New remote packets" section below.
3663 * Better reconstruction of tracepoints after disconnected tracing
3665 GDB will attempt to download the original source form of tracepoint
3666 definitions when starting a trace run, and then will upload these
3667 upon reconnection to the target, resulting in a more accurate
3668 reconstruction of the tracepoints that are in use on the target.
3672 You can now exercise direct control over the ways that GDB can
3673 affect your program. For instance, you can disallow the setting of
3674 breakpoints, so that the program can run continuously (assuming
3675 non-stop mode). In addition, the "observer" variable is available
3676 to switch all of the different controls; in observer mode, GDB
3677 cannot affect the target's behavior at all, which is useful for
3678 tasks like diagnosing live systems in the field.
3680 * The new convenience variable $_thread holds the number of the
3683 * New remote packets
3687 Return the address of the Windows Thread Information Block of a given thread.
3691 In response to several of the tracepoint packets, the target may now
3692 also respond with a number of intermediate `qRelocInsn' request
3693 packets before the final result packet, to have GDB handle
3694 relocating an instruction to execute at a different address. This
3695 is particularly useful for stubs that support fast tracepoints. GDB
3696 reports support for this feature in the qSupported packet.
3700 List static tracepoint markers in the target program.
3704 List static tracepoint markers at a given address in the target
3707 qXfer:statictrace:read
3709 Read the static trace data collected (by a `collect $_sdata'
3710 tracepoint action). The remote stub reports support for this packet
3711 to gdb's qSupported query.
3715 Send the current settings of GDB's permission flags.
3719 Send part of the source (textual) form of a tracepoint definition,
3720 which includes location, conditional, and action list.
3722 * The source command now accepts a -s option to force searching for the
3723 script in the source search path even if the script name specifies
3726 * New features in the GDB remote stub, GDBserver
3728 - GDBserver now support tracepoints (including fast tracepoints, and
3729 static tracepoints). The feature is currently supported by the
3730 i386-linux and amd64-linux builds. See the "Tracepoints support
3731 in gdbserver" section in the manual for more information.
3733 GDBserver JIT compiles the tracepoint's conditional agent
3734 expression bytecode into native code whenever possible for low
3735 overhead dynamic tracepoints conditionals. For such tracepoints,
3736 an expression that examines program state is evaluated when the
3737 tracepoint is reached, in order to determine whether to capture
3738 trace data. If the condition is simple and false, processing the
3739 tracepoint finishes very quickly and no data is gathered.
3741 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3742 for static tracepoints support.
3744 - GDBserver now supports x86_64 Windows 64-bit debugging.
3746 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3747 it understands register description.
3749 * The --batch flag now disables pagination and queries.
3751 * X86 general purpose registers
3753 GDB now supports reading/writing byte, word and double-word x86
3754 general purpose registers directly. This means you can use, say,
3755 $ah or $ax to refer, respectively, to the byte register AH and
3756 16-bit word register AX that are actually portions of the 32-bit
3757 register EAX or 64-bit register RAX.
3759 * The `commands' command now accepts a range of breakpoints to modify.
3760 A plain `commands' following a command that creates multiple
3761 breakpoints affects all the breakpoints set by that command. This
3762 applies to breakpoints set by `rbreak', and also applies when a
3763 single `break' command creates multiple breakpoints (e.g.,
3764 breakpoints on overloaded c++ functions).
3766 * The `rbreak' command now accepts a filename specification as part of
3767 its argument, limiting the functions selected by the regex to those
3768 in the specified file.
3770 * Support for remote debugging Windows and SymbianOS shared libraries
3771 from Unix hosts has been improved. Non Windows GDB builds now can
3772 understand target reported file names that follow MS-DOS based file
3773 system semantics, such as file names that include drive letters and
3774 use the backslash character as directory separator. This makes it
3775 possible to transparently use the "set sysroot" and "set
3776 solib-search-path" on Unix hosts to point as host copies of the
3777 target's shared libraries. See the new command "set
3778 target-file-system-kind" described below, and the "Commands to
3779 specify files" section in the user manual for more information.
3783 eval template, expressions...
3784 Convert the values of one or more expressions under the control
3785 of the string template to a command line, and call it.
3787 set target-file-system-kind unix|dos-based|auto
3788 show target-file-system-kind
3789 Set or show the assumed file system kind for target reported file
3792 save breakpoints <filename>
3793 Save all current breakpoint definitions to a file suitable for use
3794 in a later debugging session. To read the saved breakpoint
3795 definitions, use the `source' command.
3797 `save tracepoints' is a new alias for `save-tracepoints'. The latter
3800 info static-tracepoint-markers
3801 Display information about static tracepoint markers in the target.
3803 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
3804 Define a static tracepoint by probing a marker at the given
3805 function, line, address, or marker ID.
3809 Enable and disable observer mode.
3811 set may-write-registers on|off
3812 set may-write-memory on|off
3813 set may-insert-breakpoints on|off
3814 set may-insert-tracepoints on|off
3815 set may-insert-fast-tracepoints on|off
3816 set may-interrupt on|off
3817 Set individual permissions for GDB effects on the target. Note that
3818 some of these settings can have undesirable or surprising
3819 consequences, particularly when changed in the middle of a session.
3820 For instance, disabling the writing of memory can prevent
3821 breakpoints from being inserted, cause single-stepping to fail, or
3822 even crash your program, if you disable after breakpoints have been
3823 inserted. However, GDB should not crash.
3825 set record memory-query on|off
3826 show record memory-query
3827 Control whether to stop the inferior if memory changes caused
3828 by an instruction cannot be recorded.
3833 The disassemble command now supports "start,+length" form of two arguments.
3837 ** GDB now provides a new directory location, called the python directory,
3838 where Python scripts written for GDB can be installed. The location
3839 of that directory is <data-directory>/python, where <data-directory>
3840 is the GDB data directory. For more details, see section `Scripting
3841 GDB using Python' in the manual.
3843 ** The GDB Python API now has access to breakpoints, symbols, symbol
3844 tables, program spaces, inferiors, threads and frame's code blocks.
3845 Additionally, GDB Parameters can now be created from the API, and
3846 manipulated via set/show in the CLI.
3848 ** New functions gdb.target_charset, gdb.target_wide_charset,
3849 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3851 ** New exception gdb.GdbError.
3853 ** Pretty-printers are now also looked up in the current program space.
3855 ** Pretty-printers can now be individually enabled and disabled.
3857 ** GDB now looks for names of Python scripts to auto-load in a
3858 special section named `.debug_gdb_scripts', in addition to looking
3859 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
3861 * Tracepoint actions were unified with breakpoint commands. In particular,
3862 there are no longer differences in "info break" output for breakpoints and
3863 tracepoints and the "commands" command can be used for both tracepoints and
3864 regular breakpoints.
3868 ARM Symbian arm*-*-symbianelf*
3870 * D language support.
3871 GDB now supports debugging programs written in the D programming
3874 * GDB now supports the extended ptrace interface for PowerPC which is
3875 available since Linux kernel version 2.6.34. This automatically enables
3876 any hardware breakpoints and additional hardware watchpoints available in
3877 the processor. The old ptrace interface exposes just one hardware
3878 watchpoint and no hardware breakpoints.
3880 * GDB is now able to use the Data Value Compare (DVC) register available on
3881 embedded PowerPC processors to implement in hardware simple watchpoint
3882 conditions of the form:
3884 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3886 This works in native GDB running on Linux kernels with the extended ptrace
3887 interface mentioned above.
3889 *** Changes in GDB 7.1
3893 ** Namespace Support
3895 GDB now supports importing of namespaces in C++. This enables the
3896 user to inspect variables from imported namespaces. Support for
3897 namepace aliasing has also been added. So, if a namespace is
3898 aliased in the current scope (e.g. namepace C=A; ) the user can
3899 print variables using the alias (e.g. (gdb) print C::x).
3903 All known bugs relating to the printing of virtual base class were
3904 fixed. It is now possible to call overloaded static methods using a
3909 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3910 and reinterpret_cast<> are now handled by the C++ expression parser.
3914 Xilinx MicroBlaze microblaze-*-*
3919 Xilinx MicroBlaze microblaze
3922 * Multi-program debugging.
3924 GDB now has support for multi-program (a.k.a. multi-executable or
3925 multi-exec) debugging. This allows for debugging multiple inferiors
3926 simultaneously each running a different program under the same GDB
3927 session. See "Debugging Multiple Inferiors and Programs" in the
3928 manual for more information. This implied some user visible changes
3929 in the multi-inferior support. For example, "info inferiors" now
3930 lists inferiors that are not running yet or that have exited
3931 already. See also "New commands" and "New options" below.
3933 * New tracing features
3935 GDB's tracepoint facility now includes several new features:
3937 ** Trace state variables
3939 GDB tracepoints now include support for trace state variables, which
3940 are variables managed by the target agent during a tracing
3941 experiment. They are useful for tracepoints that trigger each
3942 other, so for instance one tracepoint can count hits in a variable,
3943 and then a second tracepoint has a condition that is true when the
3944 count reaches a particular value. Trace state variables share the
3945 $-syntax of GDB convenience variables, and can appear in both
3946 tracepoint actions and condition expressions. Use the "tvariable"
3947 command to create, and "info tvariables" to view; see "Trace State
3948 Variables" in the manual for more detail.
3952 GDB now includes an option for defining fast tracepoints, which
3953 targets may implement more efficiently, such as by installing a jump
3954 into the target agent rather than a trap instruction. The resulting
3955 speedup can be by two orders of magnitude or more, although the
3956 tradeoff is that some program locations on some target architectures
3957 might not allow fast tracepoint installation, for instance if the
3958 instruction to be replaced is shorter than the jump. To request a
3959 fast tracepoint, use the "ftrace" command, with syntax identical to
3960 the regular trace command.
3962 ** Disconnected tracing
3964 It is now possible to detach GDB from the target while it is running
3965 a trace experiment, then reconnect later to see how the experiment
3966 is going. In addition, a new variable disconnected-tracing lets you
3967 tell the target agent whether to continue running a trace if the
3968 connection is lost unexpectedly.
3972 GDB now has the ability to save the trace buffer into a file, and
3973 then use that file as a target, similarly to you can do with
3974 corefiles. You can select trace frames, print data that was
3975 collected in them, and use tstatus to display the state of the
3976 tracing run at the moment that it was saved. To create a trace
3977 file, use "tsave <filename>", and to use it, do "target tfile
3980 ** Circular trace buffer
3982 You can ask the target agent to handle the trace buffer as a
3983 circular buffer, discarding the oldest trace frames to make room for
3984 newer ones, by setting circular-trace-buffer to on. This feature may
3985 not be available for all target agents.
3990 The disassemble command, when invoked with two arguments, now requires
3991 the arguments to be comma-separated.
3994 The info variables command now displays variable definitions. Files
3995 which only declare a variable are not shown.
3998 The source command is now capable of sourcing Python scripts.
3999 This feature is dependent on the debugger being build with Python
4002 Related to this enhancement is also the introduction of a new command
4003 "set script-extension" (see below).
4005 * New commands (for set/show, see "New options" below)
4007 record save [<FILENAME>]
4008 Save a file (in core file format) containing the process record
4009 execution log for replay debugging at a later time.
4011 record restore <FILENAME>
4012 Restore the process record execution log that was saved at an
4013 earlier time, for replay debugging.
4015 add-inferior [-copies <N>] [-exec <FILENAME>]
4018 clone-inferior [-copies <N>] [ID]
4019 Make a new inferior ready to execute the same program another
4020 inferior has loaded.
4025 maint info program-spaces
4026 List the program spaces loaded into GDB.
4028 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
4029 show remote interrupt-sequence
4030 Allow the user to select one of ^C, a BREAK signal or BREAK-g
4031 as the sequence to the remote target in order to interrupt the execution.
4032 Ctrl-C is a default. Some system prefers BREAK which is high level of
4033 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
4034 Magic SysRq g. It is BREAK signal and character 'g'.
4036 set remote interrupt-on-connect [on | off]
4037 show remote interrupt-on-connect
4038 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
4039 remote target when gdb connects to it. This is needed when you debug
4042 set remotebreak [on | off]
4044 Deprecated. Use "set/show remote interrupt-sequence" instead.
4046 tvariable $NAME [ = EXP ]
4047 Create or modify a trace state variable.
4050 List trace state variables and their values.
4052 delete tvariable $NAME ...
4053 Delete one or more trace state variables.
4056 Evaluate the given expressions without collecting anything into the
4057 trace buffer. (Valid in tracepoint actions only.)
4059 ftrace FN / FILE:LINE / *ADDR
4060 Define a fast tracepoint at the given function, line, or address.
4062 * New expression syntax
4064 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
4065 GDB now parses 0b101010 identically with 42.
4069 set follow-exec-mode new|same
4070 show follow-exec-mode
4071 Control whether GDB reuses the same inferior across an exec call or
4072 creates a new one. This is useful to be able to restart the old
4073 executable after the inferior having done an exec call.
4075 set default-collect EXPR, ...
4076 show default-collect
4077 Define a list of expressions to be collected at each tracepoint.
4078 This is a useful way to ensure essential items are not overlooked,
4079 such as registers or a critical global variable.
4081 set disconnected-tracing
4082 show disconnected-tracing
4083 If set to 1, the target is instructed to continue tracing if it
4084 loses its connection to GDB. If 0, the target is to stop tracing
4087 set circular-trace-buffer
4088 show circular-trace-buffer
4089 If set to on, the target is instructed to use a circular trace buffer
4090 and discard the oldest trace frames instead of stopping the trace due
4091 to a full trace buffer. If set to off, the trace stops when the buffer
4092 fills up. Some targets may not support this.
4094 set script-extension off|soft|strict
4095 show script-extension
4096 If set to "off", the debugger does not perform any script language
4097 recognition, and all sourced files are assumed to be GDB scripts.
4098 If set to "soft" (the default), files are sourced according to
4099 filename extension, falling back to GDB scripts if the first
4101 If set to "strict", files are sourced according to filename extension.
4103 set ada trust-PAD-over-XVS on|off
4104 show ada trust-PAD-over-XVS
4105 If off, activate a workaround against a bug in the debugging information
4106 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
4107 the GCC sources for more information about the GNAT encoding and
4108 PAD types in particular). It is always safe to set this option to
4109 off, but this introduces a slight performance penalty. The default
4112 * Python API Improvements
4114 ** GDB provides the new class gdb.LazyString. This is useful in
4115 some pretty-printing cases. The new method gdb.Value.lazy_string
4116 provides a simple way to create objects of this type.
4118 ** The fields returned by gdb.Type.fields now have an
4119 `is_base_class' attribute.
4121 ** The new method gdb.Type.range returns the range of an array type.
4123 ** The new method gdb.parse_and_eval can be used to parse and
4124 evaluate an expression.
4126 * New remote packets
4129 Define a trace state variable.
4132 Get the current value of a trace state variable.
4135 Set desired tracing behavior upon disconnection.
4138 Set the trace buffer to be linear or circular.
4141 Get data about the tracepoints currently in use.
4145 Process record now works correctly with hardware watchpoints.
4147 Multiple bug fixes have been made to the mips-irix port, making it
4148 much more reliable. In particular:
4149 - Debugging threaded applications is now possible again. Previously,
4150 GDB would hang while starting the program, or while waiting for
4151 the program to stop at a breakpoint.
4152 - Attaching to a running process no longer hangs.
4153 - An error occurring while loading a core file has been fixed.
4154 - Changing the value of the PC register now works again. This fixes
4155 problems observed when using the "jump" command, or when calling
4156 a function from GDB, or even when assigning a new value to $pc.
4157 - With the "finish" and "return" commands, the return value for functions
4158 returning a small array is now correctly printed.
4159 - It is now possible to break on shared library code which gets executed
4160 during a shared library init phase (code executed while executing
4161 their .init section). Previously, the breakpoint would have no effect.
4162 - GDB is now able to backtrace through the signal handler for
4163 non-threaded programs.
4165 PIE (Position Independent Executable) programs debugging is now supported.
4166 This includes debugging execution of PIC (Position Independent Code) shared
4167 libraries although for that, it should be possible to run such libraries as an
4170 *** Changes in GDB 7.0
4172 * GDB now has an interface for JIT compilation. Applications that
4173 dynamically generate code can create symbol files in memory and register
4174 them with GDB. For users, the feature should work transparently, and
4175 for JIT developers, the interface is documented in the GDB manual in the
4176 "JIT Compilation Interface" chapter.
4178 * Tracepoints may now be conditional. The syntax is as for
4179 breakpoints; either an "if" clause appended to the "trace" command,
4180 or the "condition" command is available. GDB sends the condition to
4181 the target for evaluation using the same bytecode format as is used
4182 for tracepoint actions.
4184 * The disassemble command now supports: an optional /r modifier, print the
4185 raw instructions in hex as well as in symbolic form, and an optional /m
4186 modifier to print mixed source+assembly.
4188 * Process record and replay
4190 In a architecture environment that supports ``process record and
4191 replay'', ``process record and replay'' target can record a log of
4192 the process execution, and replay it with both forward and reverse
4195 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
4196 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
4197 set execution-direction {forward|reverse}, for targets that support
4200 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
4201 feature is available with a native GDB running on kernel version
4204 * GDB now has support for multi-byte and wide character sets on the
4205 target. Strings whose character type is wchar_t, char16_t, or
4206 char32_t are now correctly printed. GDB supports wide- and unicode-
4207 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
4208 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
4209 `printf'. This feature requires iconv to work properly; if your
4210 system does not have a working iconv, GDB can use GNU libiconv. See
4211 the installation instructions for more information.
4213 * GDB now supports automatic retrieval of shared library files from
4214 remote targets. To use this feature, specify a system root that begins
4215 with the `remote:' prefix, either via the `set sysroot' command or via
4216 the `--with-sysroot' configure-time option.
4218 * "info sharedlibrary" now takes an optional regex of libraries to show,
4219 and it now reports if a shared library has no debugging information.
4221 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
4222 now complete on file names.
4224 * When completing in expressions, gdb will attempt to limit
4225 completions to allowable structure or union fields, where appropriate.
4226 For instance, consider:
4228 # struct example { int f1; double f2; };
4229 # struct example variable;
4232 If the user types TAB at the end of this command line, the available
4233 completions will be "f1" and "f2".
4235 * Inlined functions are now supported. They show up in backtraces, and
4236 the "step", "next", and "finish" commands handle them automatically.
4238 * GDB now supports the token-splicing (##) and stringification (#)
4239 operators when expanding macros. It also supports variable-arity
4242 * GDB now supports inspecting extra signal information, exported by
4243 the new $_siginfo convenience variable. The feature is currently
4244 implemented on linux ARM, i386 and amd64.
4246 * GDB can now display the VFP floating point registers and NEON vector
4247 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
4248 can provide these registers (requires Linux 2.6.30 or later). Remote
4249 and simulator targets may also provide them.
4251 * New remote packets
4254 Search memory for a sequence of bytes.
4257 Turn off `+'/`-' protocol acknowledgments to permit more efficient
4258 operation over reliable transport links. Use of this packet is
4259 controlled by the `set remote noack-packet' command.
4262 Kill the process with the specified process ID. Use this in preference
4263 to `k' when multiprocess protocol extensions are supported.
4266 Obtains additional operating system information
4270 Read or write additional signal information.
4272 * Removed remote protocol undocumented extension
4274 An undocumented extension to the remote protocol's `S' stop reply
4275 packet that permitted the stub to pass a process id was removed.
4276 Remote servers should use the `T' stop reply packet instead.
4278 * GDB now supports multiple function calling conventions according to the
4279 DWARF-2 DW_AT_calling_convention function attribute.
4281 * The SH target utilizes the aforementioned change to distinguish between gcc
4282 and Renesas calling convention. It also adds the new CLI commands
4283 `set/show sh calling-convention'.
4285 * GDB can now read compressed debug sections, as produced by GNU gold
4286 with the --compress-debug-sections=zlib flag.
4288 * 64-bit core files are now supported on AIX.
4290 * Thread switching is now supported on Tru64.
4292 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
4293 which will be allocated using malloc later in program execution.
4295 * The qXfer:libraries:read remote protocol packet now allows passing a
4296 list of section offsets.
4298 * On GNU/Linux, GDB can now attach to stopped processes. Several race
4299 conditions handling signals delivered during attach or thread creation
4300 have also been fixed.
4302 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
4303 From the user's standpoint, all unqualified instances of True and False
4304 are treated as the standard definitions, regardless of context.
4306 * GDB now parses C++ symbol and type names more flexibly. For
4309 template<typename T> class C { };
4312 GDB will now correctly handle all of:
4314 ptype C<char const *>
4315 ptype C<char const*>
4316 ptype C<const char *>
4317 ptype C<const char*>
4319 * New features in the GDB remote stub, gdbserver
4321 - The "--wrapper" command-line argument tells gdbserver to use a
4322 wrapper program to launch programs for debugging.
4324 - On PowerPC and S/390 targets, it is now possible to use a single
4325 gdbserver executable to debug both 32-bit and 64-bit programs.
4326 (This requires gdbserver itself to be built as a 64-bit executable.)
4328 - gdbserver uses the new noack protocol mode for TCP connections to
4329 reduce communications latency, if also supported and enabled in GDB.
4331 - Support for the sparc64-linux-gnu target is now included in
4334 - The amd64-linux build of gdbserver now supports debugging both
4335 32-bit and 64-bit programs.
4337 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
4338 now support hardware watchpoints, and will use them automatically
4343 GDB now has support for scripting using Python. Whether this is
4344 available is determined at configure time.
4346 New GDB commands can now be written in Python.
4348 * Ada tasking support
4350 Ada tasks can now be inspected in GDB. The following commands have
4354 Print the list of Ada tasks.
4356 Print detailed information about task number N.
4358 Print the task number of the current task.
4360 Switch the context of debugging to task number N.
4362 * Support for user-defined prefixed commands. The "define" command can
4363 add new commands to existing prefixes, e.g. "target".
4365 * Multi-inferior, multi-process debugging.
4367 GDB now has generalized support for multi-inferior debugging. See
4368 "Debugging Multiple Inferiors" in the manual for more information.
4369 Although availability still depends on target support, the command
4370 set is more uniform now. The GNU/Linux specific multi-forks support
4371 has been migrated to this new framework. This implied some user
4372 visible changes; see "New commands" and also "Removed commands"
4375 * Target descriptions can now describe the target OS ABI. See the
4376 "Target Description Format" section in the user manual for more
4379 * Target descriptions can now describe "compatible" architectures
4380 to indicate that the target can execute applications for a different
4381 architecture in addition to those for the main target architecture.
4382 See the "Target Description Format" section in the user manual for
4385 * Multi-architecture debugging.
4387 GDB now includes general supports for debugging applications on
4388 hybrid systems that use more than one single processor architecture
4389 at the same time. Each such hybrid architecture still requires
4390 specific support to be added. The only hybrid architecture supported
4391 in this version of GDB is the Cell Broadband Engine.
4393 * GDB now supports integrated debugging of Cell/B.E. applications that
4394 use both the PPU and SPU architectures. To enable support for hybrid
4395 Cell/B.E. debugging, you need to configure GDB to support both the
4396 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
4397 --enable-targets configure option.
4399 * Non-stop mode debugging.
4401 For some targets, GDB now supports an optional mode of operation in
4402 which you can examine stopped threads while other threads continue
4403 to execute freely. This is referred to as non-stop mode, with the
4404 old mode referred to as all-stop mode. See the "Non-Stop Mode"
4405 section in the user manual for more information.
4407 To be able to support remote non-stop debugging, a remote stub needs
4408 to implement the non-stop mode remote protocol extensions, as
4409 described in the "Remote Non-Stop" section of the user manual. The
4410 GDB remote stub, gdbserver, has been adjusted to support these
4411 extensions on linux targets.
4413 * New commands (for set/show, see "New options" below)
4415 catch syscall [NAME(S) | NUMBER(S)]
4416 Catch system calls. Arguments, which should be names of system
4417 calls or their numbers, mean catch only those syscalls. Without
4418 arguments, every syscall will be caught. When the inferior issues
4419 any of the specified syscalls, GDB will stop and announce the system
4420 call, both when it is called and when its call returns. This
4421 feature is currently available with a native GDB running on the
4422 Linux Kernel, under the following architectures: x86, x86_64,
4423 PowerPC and PowerPC64.
4425 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
4427 Search memory for a sequence of bytes.
4429 maint set python print-stack
4430 maint show python print-stack
4431 Show a stack trace when an error is encountered in a Python script.
4434 Invoke CODE by passing it to the Python interpreter.
4439 These allow macros to be defined, undefined, and listed
4443 Show operating system information about processes.
4446 List the inferiors currently under GDB's control.
4449 Switch focus to inferior number NUM.
4452 Detach from inferior number NUM.
4455 Kill inferior number NUM.
4459 set spu stop-on-load
4460 show spu stop-on-load
4461 Control whether to stop for new SPE threads during Cell/B.E. debugging.
4463 set spu auto-flush-cache
4464 show spu auto-flush-cache
4465 Control whether to automatically flush the software-managed cache
4466 during Cell/B.E. debugging.
4468 set sh calling-convention
4469 show sh calling-convention
4470 Control the calling convention used when calling SH target functions.
4473 show debug timestamp
4474 Control display of timestamps with GDB debugging output.
4476 set disassemble-next-line
4477 show disassemble-next-line
4478 Control display of disassembled source lines or instructions when
4481 set remote noack-packet
4482 show remote noack-packet
4483 Set/show the use of remote protocol QStartNoAckMode packet. See above
4484 under "New remote packets."
4486 set remote query-attached-packet
4487 show remote query-attached-packet
4488 Control use of remote protocol `qAttached' (query-attached) packet.
4490 set remote read-siginfo-object
4491 show remote read-siginfo-object
4492 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4495 set remote write-siginfo-object
4496 show remote write-siginfo-object
4497 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4500 set remote reverse-continue
4501 show remote reverse-continue
4502 Control use of remote protocol 'bc' (reverse-continue) packet.
4504 set remote reverse-step
4505 show remote reverse-step
4506 Control use of remote protocol 'bs' (reverse-step) packet.
4508 set displaced-stepping
4509 show displaced-stepping
4510 Control displaced stepping mode. Displaced stepping is a way to
4511 single-step over breakpoints without removing them from the debuggee.
4512 Also known as "out-of-line single-stepping".
4515 show debug displaced
4516 Control display of debugging info for displaced stepping.
4518 maint set internal-error
4519 maint show internal-error
4520 Control what GDB does when an internal error is detected.
4522 maint set internal-warning
4523 maint show internal-warning
4524 Control what GDB does when an internal warning is detected.
4529 Use a wrapper program to launch programs for debugging.
4531 set multiple-symbols (all|ask|cancel)
4532 show multiple-symbols
4533 The value of this variable can be changed to adjust the debugger behavior
4534 when an expression or a breakpoint location contains an ambiguous symbol
4535 name (an overloaded function name, for instance).
4537 set breakpoint always-inserted
4538 show breakpoint always-inserted
4539 Keep breakpoints always inserted in the target, as opposed to inserting
4540 them when resuming the target, and removing them when the target stops.
4541 This option can improve debugger performance on slow remote targets.
4543 set arm fallback-mode (arm|thumb|auto)
4544 show arm fallback-mode
4545 set arm force-mode (arm|thumb|auto)
4547 These commands control how ARM GDB determines whether instructions
4548 are ARM or Thumb. The default for both settings is auto, which uses
4549 the current CPSR value for instructions without symbols; previous
4550 versions of GDB behaved as if "set arm fallback-mode arm".
4552 set disable-randomization
4553 show disable-randomization
4554 Standalone programs run with the virtual address space randomization enabled
4555 by default on some platforms. This option keeps the addresses stable across
4556 multiple debugging sessions.
4560 Control whether other threads are stopped or not when some thread hits
4565 Requests that asynchronous execution is enabled in the target, if available.
4566 In this case, it's possible to resume target in the background, and interact
4567 with GDB while the target is running. "show target-async" displays the
4568 current state of asynchronous execution of the target.
4570 set target-wide-charset
4571 show target-wide-charset
4572 The target-wide-charset is the name of the character set that GDB
4573 uses when printing characters whose type is wchar_t.
4575 set tcp auto-retry (on|off)
4577 set tcp connect-timeout
4578 show tcp connect-timeout
4579 These commands allow GDB to retry failed TCP connections to a remote stub
4580 with a specified timeout period; this is useful if the stub is launched
4581 in parallel with GDB but may not be ready to accept connections immediately.
4583 set libthread-db-search-path
4584 show libthread-db-search-path
4585 Control list of directories which GDB will search for appropriate
4588 set schedule-multiple (on|off)
4589 show schedule-multiple
4590 Allow GDB to resume all threads of all processes or only threads of
4591 the current process.
4595 Use more aggressive caching for accesses to the stack. This improves
4596 performance of remote debugging (particularly backtraces) without
4597 affecting correctness.
4599 set interactive-mode (on|off|auto)
4600 show interactive-mode
4601 Control whether GDB runs in interactive mode (on) or not (off).
4602 When in interactive mode, GDB waits for the user to answer all
4603 queries. Otherwise, GDB does not wait and assumes the default
4604 answer. When set to auto (the default), GDB determines which
4605 mode to use based on the stdin settings.
4610 For program forks, this is replaced by the new more generic `info
4611 inferiors' command. To list checkpoints, you can still use the
4612 `info checkpoints' command, which was an alias for the `info forks'
4616 Replaced by the new `inferior' command. To switch between
4617 checkpoints, you can still use the `restart' command, which was an
4618 alias for the `fork' command.
4621 This is removed, since some targets don't have a notion of
4622 processes. To switch between processes, you can still use the
4623 `inferior' command using GDB's own inferior number.
4626 For program forks, this is replaced by the new more generic `kill
4627 inferior' command. To delete a checkpoint, you can still use the
4628 `delete checkpoint' command, which was an alias for the `delete
4632 For program forks, this is replaced by the new more generic `detach
4633 inferior' command. To detach a checkpoint, you can still use the
4634 `detach checkpoint' command, which was an alias for the `detach
4637 * New native configurations
4639 x86/x86_64 Darwin i[34567]86-*-darwin*
4641 x86_64 MinGW x86_64-*-mingw*
4645 Lattice Mico32 lm32-*
4646 x86 DICOS i[34567]86-*-dicos*
4647 x86_64 DICOS x86_64-*-dicos*
4650 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4651 (mingw32ce) debugging.
4657 These commands were actually not implemented on any target.
4659 *** Changes in GDB 6.8
4661 * New native configurations
4663 NetBSD/hppa hppa*-*netbsd*
4664 Xtensa GNU/Linux xtensa*-*-linux*
4668 NetBSD/hppa hppa*-*-netbsd*
4669 Xtensa GNU/Linux xtensa*-*-linux*
4671 * Change in command line behavior -- corefiles vs. process ids.
4673 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4674 attaching to process NUMBER fails, GDB no longer attempts to open a
4675 core file named NUMBER. Attaching to a program using the -c option
4676 is no longer supported. Instead, use the '-p' or '--pid' options.
4678 * GDB can now be built as a native debugger for debugging Windows x86
4679 (mingw32) Portable Executable (PE) programs.
4681 * Pending breakpoints no longer change their number when their address
4684 * GDB now supports breakpoints with multiple locations,
4685 including breakpoints on C++ constructors, inside C++ templates,
4686 and in inlined functions.
4688 * GDB's ability to debug optimized code has been improved. GDB more
4689 accurately identifies function bodies and lexical blocks that occupy
4690 more than one contiguous range of addresses.
4692 * Target descriptions can now describe registers for PowerPC.
4694 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4695 registers on PowerPC targets.
4697 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4698 targets even when the libthread_db library is not available.
4700 * The GDB remote stub, gdbserver, now supports the new file transfer
4701 commands (remote put, remote get, and remote delete).
4703 * The GDB remote stub, gdbserver, now supports run and attach in
4704 extended-remote mode.
4706 * hppa*64*-*-hpux11* target broken
4707 The debugger is unable to start a program and fails with the following
4708 error: "Error trying to get information about dynamic linker".
4709 The gdb-6.7 release is also affected.
4711 * GDB now supports the --enable-targets= configure option to allow
4712 building a single GDB executable that supports multiple remote
4713 target architectures.
4715 * GDB now supports debugging C and C++ programs which use the
4716 Decimal Floating Point extension. In addition, the PowerPC target
4717 now has a set of pseudo-registers to inspect decimal float values
4718 stored in two consecutive float registers.
4720 * The -break-insert MI command can optionally create pending
4723 * Improved support for debugging Ada
4724 Many improvements to the Ada language support have been made. These
4726 - Better support for Ada2005 interface types
4727 - Improved handling of arrays and slices in general
4728 - Better support for Taft-amendment types
4729 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4731 - Improved command completion in Ada
4734 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4739 set print frame-arguments (all|scalars|none)
4740 show print frame-arguments
4741 The value of this variable can be changed to control which argument
4742 values should be printed by the debugger when displaying a frame.
4747 Transfer files to and from a remote target, and delete remote files.
4754 Transfer files to and from a remote target, and delete remote files.
4756 * New remote packets
4763 Open, close, read, write, and delete files on the remote system.
4766 Attach to an existing process on the remote system, in extended-remote
4770 Run a new process on the remote system, in extended-remote mode.
4772 *** Changes in GDB 6.7
4774 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
4775 bfd, libiberty and opcodes, as revealed by static analysis donated by
4776 Coverity, Inc. (http://scan.coverity.com).
4778 * When looking up multiply-defined global symbols, GDB will now prefer the
4779 symbol definition in the current shared library if it was built using the
4780 -Bsymbolic linker option.
4782 * When the Text User Interface (TUI) is not configured, GDB will now
4783 recognize the -tui command-line option and print a message that the TUI
4786 * The GDB remote stub, gdbserver, now has lower overhead for high
4787 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
4789 * GDB for MIPS targets now autodetects whether a remote target provides
4790 32-bit or 64-bit register values.
4792 * Support for C++ member pointers has been improved.
4794 * GDB now understands XML target descriptions, which specify the
4795 target's overall architecture. GDB can read a description from
4796 a local file or over the remote serial protocol.
4798 * Vectors of single-byte data use a new integer type which is not
4799 automatically displayed as character or string data.
4801 * The /s format now works with the print command. It displays
4802 arrays of single-byte integers and pointers to single-byte integers
4805 * Target descriptions can now describe target-specific registers,
4806 for architectures which have implemented the support (currently
4807 only ARM, M68K, and MIPS).
4809 * GDB and the GDB remote stub, gdbserver, now support the XScale
4812 * The GDB remote stub, gdbserver, has been updated to support
4813 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4814 has been rewritten to use the standard GDB remote protocol.
4816 * GDB can now step into C++ functions which are called through thunks.
4818 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4820 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4821 layout. It also supports a TextSeg= and DataSeg= response when only
4822 segment base addresses (rather than offsets) are available.
4824 * The /i format now outputs any trailing branch delay slot instructions
4825 immediately following the last instruction within the count specified.
4827 * The GDB remote protocol "T" stop reply packet now supports a
4828 "library" response. Combined with the new "qXfer:libraries:read"
4829 packet, this response allows GDB to debug shared libraries on targets
4830 where the operating system manages the list of loaded libraries (e.g.
4831 Windows and SymbianOS).
4833 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4834 (DLLs) on Windows and Windows CE targets.
4836 * GDB now supports a faster verification that a .debug file matches its binary
4837 according to its build-id signature, if the signature is present.
4843 Enable or disable hardware flow control (RTS/CTS) on the serial port
4844 when debugging using remote targets.
4846 set mem inaccessible-by-default
4847 show mem inaccessible-by-default
4848 If the target supplies a memory map, for instance via the remote
4849 protocol's "qXfer:memory-map:read" packet, setting this variable
4850 prevents GDB from accessing memory outside the memory map. This
4851 is useful for targets with memory mapped registers or which react
4852 badly to accesses of unmapped address space.
4854 set breakpoint auto-hw
4855 show breakpoint auto-hw
4856 If the target supplies a memory map, for instance via the remote
4857 protocol's "qXfer:memory-map:read" packet, setting this variable
4858 lets GDB use hardware breakpoints automatically for memory regions
4859 where it can not use software breakpoints. This covers both the
4860 "break" command and internal breakpoints used for other commands
4861 including "next" and "finish".
4864 catch exception unhandled
4865 Stop the program execution when Ada exceptions are raised.
4868 Stop the program execution when an Ada assertion failed.
4872 Set an alternate system root for target files. This is a more
4873 general version of "set solib-absolute-prefix", which is now
4874 an alias to "set sysroot".
4877 Provide extended SPU facility status information. This set of
4878 commands is available only when debugging the Cell/B.E. SPU
4881 * New native configurations
4883 OpenBSD/sh sh*-*openbsd*
4886 unset tdesc filename
4888 Use the specified local file as an XML target description, and do
4889 not query the target for its built-in description.
4893 OpenBSD/sh sh*-*-openbsd*
4894 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4895 Toshiba Media Processor mep-elf
4897 * New remote packets
4900 Ignore the specified signals; pass them directly to the debugged program
4901 without stopping other threads or reporting them to GDB.
4903 qXfer:features:read:
4904 Read an XML target description from the target, which describes its
4909 Read or write contents of an spufs file on the target system. These
4910 packets are available only on the Cell/B.E. SPU architecture.
4912 qXfer:libraries:read:
4913 Report the loaded shared libraries. Combined with new "T" packet
4914 response, this packet allows GDB to debug shared libraries on
4915 targets where the operating system manages the list of loaded
4916 libraries (e.g. Windows and SymbianOS).
4920 Support for these obsolete configurations has been removed.
4928 i[34567]86-*-lynxos*
4929 i[34567]86-*-netware*
4930 i[34567]86-*-sco3.2v5*
4931 i[34567]86-*-sco3.2v4*
4933 i[34567]86-*-sysv4.2*
4936 i[34567]86-*-unixware2*
4937 i[34567]86-*-unixware*
4946 * Other removed features
4953 Various m68k-only ROM monitors.
4960 Various Renesas ROM monitors and debugging interfaces for SH and
4965 Support for a Macraigor serial interface to on-chip debugging.
4966 GDB does not directly support the newer parallel or USB
4971 A debug information format. The predecessor to DWARF 2 and
4972 DWARF 3, which are still supported.
4974 Support for the HP aCC compiler on HP-UX/PA-RISC
4976 SOM-encapsulated symbolic debugging information, automatic
4977 invocation of pxdb, and the aCC custom C++ ABI. This does not
4978 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4979 with aCC can still be debugged on an assembly level.
4981 MIPS ".pdr" sections
4983 A MIPS-specific format used to describe stack frame layout
4984 in debugging information.
4988 GDB could work with an older version of Guile to debug
4989 the interpreter and Scheme programs running in it.
4991 set mips stack-arg-size
4992 set mips saved-gpreg-size
4994 Use "set mips abi" to control parameter passing for MIPS.
4996 *** Changes in GDB 6.6
5001 Cell Broadband Engine SPU spu-elf
5003 * GDB can now be configured as a cross-debugger targeting native Windows
5004 (mingw32) or Cygwin. It can communicate with a remote debugging stub
5005 running on a Windows system over TCP/IP to debug Windows programs.
5007 * The GDB remote stub, gdbserver, has been updated to support Windows and
5008 Cygwin debugging. Both single-threaded and multi-threaded programs are
5011 * The "set trust-readonly-sections" command works again. This command was
5012 broken in GDB 6.3, 6.4, and 6.5.
5014 * The "load" command now supports writing to flash memory, if the remote
5015 stub provides the required support.
5017 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
5018 longer requires symbolic debug information (e.g. DWARF-2).
5023 unset substitute-path
5024 show substitute-path
5025 Manage a list of substitution rules that GDB uses to rewrite the name
5026 of the directories where the sources are located. This can be useful
5027 for instance when the sources were moved to a different location
5028 between compilation and debugging.
5032 Print each CLI command as it is executed. Each command is prefixed with
5033 a number of `+' symbols representing the nesting depth.
5034 The source command now has a `-v' option to enable the same feature.
5038 The ARM Demon monitor support (RDP protocol, "target rdp").
5040 Kernel Object Display, an embedded debugging feature which only worked with
5041 an obsolete version of Cisco IOS.
5043 The 'set download-write-size' and 'show download-write-size' commands.
5045 * New remote packets
5048 Tell a stub about GDB client features, and request remote target features.
5049 The first feature implemented is PacketSize, which allows the target to
5050 specify the size of packets it can handle - to minimize the number of
5051 packets required and improve performance when connected to a remote
5055 Fetch an OS auxilliary vector from the remote stub. This packet is a
5056 more efficient replacement for qPart:auxv:read.
5058 qXfer:memory-map:read:
5059 Fetch a memory map from the remote stub, including information about
5060 RAM, ROM, and flash memory devices.
5065 Erase and program a flash memory device.
5067 * Removed remote packets
5070 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
5071 used it, and only gdbserver implemented it.
5073 *** Changes in GDB 6.5
5077 Renesas M32C/M16C m32c-elf
5079 Morpho Technologies ms1 ms1-elf
5083 init-if-undefined Initialize a convenience variable, but
5084 only if it doesn't already have a value.
5086 The following commands are presently only implemented for native GNU/Linux:
5088 checkpoint Save a snapshot of the program state.
5090 restart <n> Return the program state to a
5091 previously saved state.
5093 info checkpoints List currently saved checkpoints.
5095 delete-checkpoint <n> Delete a previously saved checkpoint.
5097 set|show detach-on-fork Tell gdb whether to detach from a newly
5098 forked process, or to keep debugging it.
5100 info forks List forks of the user program that
5101 are available to be debugged.
5103 fork <n> Switch to debugging one of several
5104 forks of the user program that are
5105 available to be debugged.
5107 delete-fork <n> Delete a fork from the list of forks
5108 that are available to be debugged (and
5109 kill the forked process).
5111 detach-fork <n> Delete a fork from the list of forks
5112 that are available to be debugged (and
5113 allow the process to continue).
5117 Morpho Technologies ms2 ms1-elf
5119 * Improved Windows host support
5121 GDB now builds as a cross debugger hosted on i686-mingw32, including
5122 native console support, and remote communications using either
5123 network sockets or serial ports.
5125 * Improved Modula-2 language support
5127 GDB can now print most types in the Modula-2 syntax. This includes:
5128 basic types, set types, record types, enumerated types, range types,
5129 pointer types and ARRAY types. Procedure var parameters are correctly
5130 printed and hexadecimal addresses and character constants are also
5131 written in the Modula-2 syntax. Best results can be obtained by using
5132 GNU Modula-2 together with the -gdwarf-2 command line option.
5136 The ARM rdi-share module.
5138 The Netware NLM debug server.
5140 *** Changes in GDB 6.4
5142 * New native configurations
5144 OpenBSD/arm arm*-*-openbsd*
5145 OpenBSD/mips64 mips64-*-openbsd*
5149 Morpho Technologies ms1 ms1-elf
5151 * New command line options
5153 --batch-silent As for --batch, but totally silent.
5154 --return-child-result The debugger will exist with the same value
5155 the child (debugged) program exited with.
5156 --eval-command COMMAND, -ex COMMAND
5157 Execute a single GDB CLI command. This may be
5158 specified multiple times and in conjunction
5159 with the --command (-x) option.
5161 * Deprecated commands removed
5163 The following commands, that were deprecated in 2000, have been
5167 set|show arm disassembly-flavor set|show arm disassembler
5168 othernames set arm disassembler
5169 set|show remotedebug set|show debug remote
5170 set|show archdebug set|show debug arch
5171 set|show eventdebug set|show debug event
5174 * New BSD user-level threads support
5176 It is now possible to debug programs using the user-level threads
5177 library on OpenBSD and FreeBSD. Currently supported (target)
5180 FreeBSD/amd64 x86_64-*-freebsd*
5181 FreeBSD/i386 i386-*-freebsd*
5182 OpenBSD/i386 i386-*-openbsd*
5184 Note that the new kernel threads libraries introduced in FreeBSD 5.x
5185 are not yet supported.
5187 * New support for Matsushita MN10300 w/sim added
5188 (Work in progress). mn10300-elf.
5190 * REMOVED configurations and files
5192 VxWorks and the XDR protocol *-*-vxworks
5193 Motorola MCORE mcore-*-*
5194 National Semiconductor NS32000 ns32k-*-*
5196 * New "set print array-indexes" command
5198 After turning this setting "on", GDB prints the index of each element
5199 when displaying arrays. The default is "off" to preserve the previous
5202 * VAX floating point support
5204 GDB now supports the not-quite-ieee VAX F and D floating point formats.
5206 * User-defined command support
5208 In addition to using $arg0..$arg9 for argument passing, it is now possible
5209 to use $argc to determine now many arguments have been passed. See the
5210 section on user-defined commands in the user manual for more information.
5212 *** Changes in GDB 6.3:
5214 * New command line option
5216 GDB now accepts -l followed by a number to set the timeout for remote
5219 * GDB works with GCC -feliminate-dwarf2-dups
5221 GDB now supports a more compact representation of DWARF-2 debug
5222 information using DW_FORM_ref_addr references. These are produced
5223 by GCC with the option -feliminate-dwarf2-dups and also by some
5224 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
5225 to use -feliminate-dwarf2-dups.
5227 * Internationalization
5229 When supported by the host system, GDB will be built with
5230 internationalization (libintl). The task of marking up the sources is
5231 continued, we're looking forward to our first translation.
5235 Initial support for debugging programs compiled with the GNAT
5236 implementation of the Ada programming language has been integrated
5237 into GDB. In this release, support is limited to expression evaluation.
5239 * New native configurations
5241 GNU/Linux/m32r m32r-*-linux-gnu
5245 GDB's remote protocol now includes support for the 'p' packet. This
5246 packet is used to fetch individual registers from a remote inferior.
5248 * END-OF-LIFE registers[] compatibility module
5250 GDB's internal register infrastructure has been completely rewritten.
5251 The new infrastructure making possible the implementation of key new
5252 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
5255 GDB 6.3 will be the last release to include the registers[]
5256 compatibility module that allowed out-of-date configurations to
5257 continue to work. This change directly impacts the following
5267 powerpc bdm protocol
5269 Unless there is activity to revive these configurations, they will be
5270 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
5272 * OBSOLETE configurations and files
5274 Configurations that have been declared obsolete in this release have
5275 been commented out. Unless there is activity to revive these
5276 configurations, the next release of GDB will have their sources
5277 permanently REMOVED.
5286 *** Changes in GDB 6.2.1:
5288 * MIPS `break main; run' gave an heuristic-fence-post warning
5290 When attempting to run even a simple program, a warning about
5291 heuristic-fence-post being hit would be reported. This problem has
5294 * MIPS IRIX 'long double' crashed GDB
5296 When examining a long double variable, GDB would get a segmentation
5297 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
5298 IRIX long double values).
5302 A bug in the VAX stack code was causing problems with the "next"
5303 command. This problem has been fixed.
5305 *** Changes in GDB 6.2:
5307 * Fix for ``many threads''
5309 On GNU/Linux systems that use the NPTL threads library, a program
5310 rapidly creating and deleting threads would confuse GDB leading to the
5313 ptrace: No such process.
5314 thread_db_get_info: cannot get thread info: generic error
5316 This problem has been fixed.
5318 * "-async" and "-noasync" options removed.
5320 Support for the broken "-noasync" option has been removed (it caused
5323 * New ``start'' command.
5325 This command runs the program until the beginning of the main procedure.
5327 * New BSD Kernel Data Access Library (libkvm) interface
5329 Using ``target kvm'' it is now possible to debug kernel core dumps and
5330 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
5331 platforms. Currently supported (native-only) configurations are:
5333 FreeBSD/amd64 x86_64-*-freebsd*
5334 FreeBSD/i386 i?86-*-freebsd*
5335 NetBSD/i386 i?86-*-netbsd*
5336 NetBSD/m68k m68*-*-netbsd*
5337 NetBSD/sparc sparc-*-netbsd*
5338 OpenBSD/amd64 x86_64-*-openbsd*
5339 OpenBSD/i386 i?86-*-openbsd*
5340 OpenBSD/m68k m68*-openbsd*
5341 OpenBSD/sparc sparc-*-openbsd*
5343 * Signal trampoline code overhauled
5345 Many generic problems with GDB's signal handling code have been fixed.
5346 These include: backtraces through non-contiguous stacks; recognition
5347 of sa_sigaction signal trampolines; backtrace from a NULL pointer
5348 call; backtrace through a signal trampoline; step into and out of
5349 signal handlers; and single-stepping in the signal trampoline.
5351 Please note that kernel bugs are a limiting factor here. These
5352 features have been shown to work on an s390 GNU/Linux system that
5353 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
5355 * Cygwin support for DWARF 2 added.
5357 * New native configurations
5359 GNU/Linux/hppa hppa*-*-linux*
5360 OpenBSD/hppa hppa*-*-openbsd*
5361 OpenBSD/m68k m68*-*-openbsd*
5362 OpenBSD/m88k m88*-*-openbsd*
5363 OpenBSD/powerpc powerpc-*-openbsd*
5364 NetBSD/vax vax-*-netbsd*
5365 OpenBSD/vax vax-*-openbsd*
5367 * END-OF-LIFE frame compatibility module
5369 GDB's internal frame infrastructure has been completely rewritten.
5370 The new infrastructure making it possible to support key new features
5371 including DWARF 2 Call Frame Information. To aid in the task of
5372 migrating old configurations to this new infrastructure, a
5373 compatibility module, that allowed old configurations to continue to
5374 work, was also included.
5376 GDB 6.2 will be the last release to include this frame compatibility
5377 module. This change directly impacts the following configurations:
5387 Unless there is activity to revive these configurations, they will be
5388 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
5390 * REMOVED configurations and files
5392 Sun 3, running SunOS 3 m68*-*-sunos3*
5393 Sun 3, running SunOS 4 m68*-*-sunos4*
5394 Sun 2, running SunOS 3 m68000-*-sunos3*
5395 Sun 2, running SunOS 4 m68000-*-sunos4*
5396 Motorola 680x0 running LynxOS m68*-*-lynxos*
5397 AT&T 3b1/Unix pc m68*-att-*
5398 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5399 decstation mips-dec-* mips-little-*
5400 riscos mips-*-riscos* mips-*-sysv*
5401 sonymips mips-sony-*
5402 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5404 *** Changes in GDB 6.1.1:
5406 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
5408 The TUI (Text-mode User Interface) is now built as part of a default
5409 GDB configuration. It is enabled by either selecting the TUI with the
5410 command line option "-i=tui" or by running the separate "gdbtui"
5411 program. For more information on the TUI, see the manual "Debugging
5414 * Pending breakpoint support (also included in GDB 6.1)
5416 Support has been added to allow you to specify breakpoints in shared
5417 libraries that have not yet been loaded. If a breakpoint location
5418 cannot be found, and the "breakpoint pending" option is set to auto,
5419 GDB queries you if you wish to make the breakpoint pending on a future
5420 shared-library load. If and when GDB resolves the breakpoint symbol,
5421 the pending breakpoint is removed as one or more regular breakpoints
5424 Pending breakpoints are very useful for GCJ Java debugging.
5426 * Fixed ISO-C build problems
5428 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
5429 non ISO-C code that stopped them being built using a more strict ISO-C
5430 compiler (e.g., IBM's C compiler).
5432 * Fixed build problem on IRIX 5
5434 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
5435 wasn't able to compile compile on an IRIX 5 system.
5437 * Added execute permission to gdb/gdbserver/configure
5439 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
5440 permission. This bug would cause configure to fail on a number of
5441 systems (Solaris, IRIX). Ref: server/519.
5443 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
5445 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
5446 has been updated to use constant array sizes.
5448 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
5450 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
5451 its generated DWARF Call Frame Info. This encoding was causing GDB to
5452 panic, that panic has been fixed. Ref: gdb/1628.
5454 * Fixed a problem when examining parameters in shared library code.
5456 When examining parameters in optimized shared library code generated
5457 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
5458 not available''. GDB now correctly displays the variable's value.
5460 *** Changes in GDB 6.1:
5462 * Removed --with-mmalloc
5464 Support for the mmalloc memory manager has been removed, as it
5465 conflicted with the internal gdb byte cache.
5467 * Changes in AMD64 configurations
5469 The AMD64 target now includes the %cs and %ss registers. As a result
5470 the AMD64 remote protocol has changed; this affects the floating-point
5471 and SSE registers. If you rely on those registers for your debugging,
5472 you should upgrade gdbserver on the remote side.
5474 * Revised SPARC target
5476 The SPARC target has been completely revised, incorporating the
5477 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
5478 support for LynxOS and SunOS 4 has been dropped. Calling functions
5479 from within GDB on operating systems with a non-executable stack
5480 (Solaris, OpenBSD) now works.
5484 GDB has a new C++ demangler which does a better job on the mangled
5485 names generated by current versions of g++. It also runs faster, so
5486 with this and other changes gdb should now start faster on large C++
5489 * DWARF 2 Location Expressions
5491 GDB support for location expressions has been extended to support function
5492 arguments and frame bases. Older versions of GDB could crash when they
5495 * C++ nested types and namespaces
5497 GDB's support for nested types and namespaces in C++ has been
5498 improved, especially if you use the DWARF 2 debugging format. (This
5499 is the default for recent versions of GCC on most platforms.)
5500 Specifically, if you have a class "Inner" defined within a class or
5501 namespace "Outer", then GDB realizes that the class's name is
5502 "Outer::Inner", not simply "Inner". This should greatly reduce the
5503 frequency of complaints about not finding RTTI symbols. In addition,
5504 if you are stopped at inside of a function defined within a namespace,
5505 GDB modifies its name lookup accordingly.
5507 * New native configurations
5509 NetBSD/amd64 x86_64-*-netbsd*
5510 OpenBSD/amd64 x86_64-*-openbsd*
5511 OpenBSD/alpha alpha*-*-openbsd*
5512 OpenBSD/sparc sparc-*-openbsd*
5513 OpenBSD/sparc64 sparc64-*-openbsd*
5515 * New debugging protocols
5517 M32R with SDI protocol m32r-*-elf*
5519 * "set prompt-escape-char" command deleted.
5521 The command "set prompt-escape-char" has been deleted. This command,
5522 and its very obscure effect on GDB's prompt, was never documented,
5523 tested, nor mentioned in the NEWS file.
5525 * OBSOLETE configurations and files
5527 Configurations that have been declared obsolete in this release have
5528 been commented out. Unless there is activity to revive these
5529 configurations, the next release of GDB will have their sources
5530 permanently REMOVED.
5532 Sun 3, running SunOS 3 m68*-*-sunos3*
5533 Sun 3, running SunOS 4 m68*-*-sunos4*
5534 Sun 2, running SunOS 3 m68000-*-sunos3*
5535 Sun 2, running SunOS 4 m68000-*-sunos4*
5536 Motorola 680x0 running LynxOS m68*-*-lynxos*
5537 AT&T 3b1/Unix pc m68*-att-*
5538 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5539 decstation mips-dec-* mips-little-*
5540 riscos mips-*-riscos* mips-*-sysv*
5541 sonymips mips-sony-*
5542 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5544 * REMOVED configurations and files
5546 SGI Irix-4.x mips-sgi-irix4 or iris4
5547 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5548 Z8000 simulator z8k-zilog-none or z8ksim
5549 Matsushita MN10200 w/simulator mn10200-*-*
5550 H8/500 simulator h8500-hitachi-hms or h8500hms
5551 HP/PA running BSD hppa*-*-bsd*
5552 HP/PA running OSF/1 hppa*-*-osf*
5553 HP/PA Pro target hppa*-*-pro*
5554 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5555 386BSD i[3456]86-*-bsd*
5556 Sequent family i[3456]86-sequent-sysv4*
5557 i[3456]86-sequent-sysv*
5558 i[3456]86-sequent-bsd*
5559 SPARC running LynxOS sparc-*-lynxos*
5560 SPARC running SunOS 4 sparc-*-sunos4*
5561 Tsqware Sparclet sparclet-*-*
5562 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5564 *** Changes in GDB 6.0:
5568 Support for debugging the Objective-C programming language has been
5569 integrated into GDB.
5571 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5573 DWARF 2's Call Frame Information makes available compiler generated
5574 information that more exactly describes the program's run-time stack.
5575 By using this information, GDB is able to provide more robust stack
5578 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5579 have been updated to use a new backtrace mechanism which includes
5580 DWARF 2 CFI support.
5584 GDB's remote protocol has been extended to include support for hosted
5585 file I/O (where the remote target uses GDB's file system). See GDB's
5586 remote protocol documentation for details.
5588 * All targets using the new architecture framework.
5590 All of GDB's targets have been updated to use the new internal
5591 architecture framework. The way is now open for future GDB releases
5592 to include cross-architecture native debugging support (i386 on amd64,
5595 * GNU/Linux's Thread Local Storage (TLS)
5597 GDB now includes support for for the GNU/Linux implementation of
5598 per-thread variables.
5600 * GNU/Linux's Native POSIX Thread Library (NPTL)
5602 GDB's thread code has been updated to work with either the new
5603 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5605 * Separate debug info.
5607 GDB, in conjunction with BINUTILS, now supports a mechanism for
5608 automatically loading debug information from a separate file. Instead
5609 of shipping full debug and non-debug versions of system libraries,
5610 system integrators can now instead ship just the stripped libraries
5611 and optional debug files.
5613 * DWARF 2 Location Expressions
5615 DWARF 2 Location Expressions allow the compiler to more completely
5616 describe the location of variables (even in optimized code) to the
5619 GDB now includes preliminary support for location expressions (support
5620 for DW_OP_piece is still missing).
5624 A number of long standing bugs that caused GDB to die while starting a
5625 Java application have been fixed. GDB's Java support is now
5626 considered "useable".
5628 * GNU/Linux support for fork, vfork, and exec.
5630 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5631 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5634 * GDB supports logging output to a file
5636 There are two new commands, "set logging" and "show logging", which can be
5637 used to capture GDB's output to a file.
5639 * The meaning of "detach" has changed for gdbserver
5641 The "detach" command will now resume the application, as documented. To
5642 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5645 * d10v, m68hc11 `regs' command deprecated
5647 The `info registers' command has been updated so that it displays the
5648 registers using a format identical to the old `regs' command.
5652 A new command, "maint set profile on/off", has been added. This command can
5653 be used to enable or disable profiling while running GDB, to profile a
5654 session or a set of commands. In addition there is a new configure switch,
5655 "--enable-profiling", which will cause GDB to be compiled with profiling
5656 data, for more informative profiling results.
5658 * Default MI syntax changed to "mi2".
5660 The default MI (machine interface) syntax, enabled by the command line
5661 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5662 "mi1", can be enabled by specifying the option "-i=mi1".
5664 Support for the original "mi0" syntax (included in GDB 5.0) has been
5667 Fix for gdb/192: removed extraneous space when displaying frame level.
5668 Fix for gdb/672: update changelist is now output in mi list format.
5669 Fix for gdb/702: a -var-assign that updates the value now shows up
5670 in a subsequent -var-update.
5672 * New native configurations.
5674 FreeBSD/amd64 x86_64-*-freebsd*
5676 * Multi-arched targets.
5678 HP/PA HPUX11 hppa*-*-hpux*
5679 Renesas M32R/D w/simulator m32r-*-elf*
5681 * OBSOLETE configurations and files
5683 Configurations that have been declared obsolete in this release have
5684 been commented out. Unless there is activity to revive these
5685 configurations, the next release of GDB will have their sources
5686 permanently REMOVED.
5688 Z8000 simulator z8k-zilog-none or z8ksim
5689 Matsushita MN10200 w/simulator mn10200-*-*
5690 H8/500 simulator h8500-hitachi-hms or h8500hms
5691 HP/PA running BSD hppa*-*-bsd*
5692 HP/PA running OSF/1 hppa*-*-osf*
5693 HP/PA Pro target hppa*-*-pro*
5694 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5695 Sequent family i[3456]86-sequent-sysv4*
5696 i[3456]86-sequent-sysv*
5697 i[3456]86-sequent-bsd*
5698 Tsqware Sparclet sparclet-*-*
5699 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5701 * REMOVED configurations and files
5704 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5705 IBM AIX PS/2 i[3456]86-*-aix
5706 i386 running Mach 3.0 i[3456]86-*-mach3*
5707 i386 running Mach i[3456]86-*-mach*
5708 i386 running OSF/1 i[3456]86-*osf1mk*
5709 HP/Apollo 68k Family m68*-apollo*-sysv*,
5711 m68*-hp-bsd*, m68*-hp-hpux*
5712 Argonaut Risc Chip (ARC) arc-*-*
5713 Mitsubishi D30V d30v-*-*
5714 Fujitsu FR30 fr30-*-elf*
5715 OS/9000 i[34]86-*-os9k
5716 I960 with MON960 i960-*-coff
5718 * MIPS $fp behavior changed
5720 The convenience variable $fp, for the MIPS, now consistently returns
5721 the address of the current frame's base. Previously, depending on the
5722 context, $fp could refer to either $sp or the current frame's base
5723 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5724 The GNU Source-Level Debugger''.
5726 *** Changes in GDB 5.3:
5728 * GNU/Linux shared library multi-threaded performance improved.
5730 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5731 `/proc', in preference to `ptrace' for memory reads. This may result
5732 in an improvement in the start-up time of multi-threaded, shared
5733 library applications when run under GDB. One GDB user writes: ``loads
5734 shared libs like mad''.
5736 * ``gdbserver'' now supports multi-threaded applications on some targets
5738 Support for debugging multi-threaded applications which use
5739 the GNU/Linux LinuxThreads package has been added for
5740 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5741 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5743 * GDB now supports C/C++ preprocessor macros.
5745 GDB now expands preprocessor macro invocations in C/C++ expressions,
5746 and provides various commands for showing macro definitions and how
5749 The new command `macro expand EXPRESSION' expands any macro
5750 invocations in expression, and shows the result.
5752 The new command `show macro MACRO-NAME' shows the definition of the
5753 macro named MACRO-NAME, and where it was defined.
5755 Most compilers don't include information about macros in the debugging
5756 information by default. In GCC 3.1, for example, you need to compile
5757 your program with the options `-gdwarf-2 -g3'. If the macro
5758 information is present in the executable, GDB will read it.
5760 * Multi-arched targets.
5762 DEC Alpha (partial) alpha*-*-*
5763 DEC VAX (partial) vax-*-*
5765 National Semiconductor NS32000 (partial) ns32k-*-*
5766 Motorola 68000 (partial) m68k-*-*
5767 Motorola MCORE mcore-*-*
5771 Fujitsu FRV architecture added by Red Hat frv*-*-*
5774 * New native configurations
5776 Alpha NetBSD alpha*-*-netbsd*
5777 SH NetBSD sh*-*-netbsdelf*
5778 MIPS NetBSD mips*-*-netbsd*
5779 UltraSPARC NetBSD sparc64-*-netbsd*
5781 * OBSOLETE configurations and files
5783 Configurations that have been declared obsolete in this release have
5784 been commented out. Unless there is activity to revive these
5785 configurations, the next release of GDB will have their sources
5786 permanently REMOVED.
5788 Mitsubishi D30V d30v-*-*
5789 OS/9000 i[34]86-*-os9k
5790 IBM AIX PS/2 i[3456]86-*-aix
5791 Fujitsu FR30 fr30-*-elf*
5792 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5793 Argonaut Risc Chip (ARC) arc-*-*
5794 i386 running Mach 3.0 i[3456]86-*-mach3*
5795 i386 running Mach i[3456]86-*-mach*
5796 i386 running OSF/1 i[3456]86-*osf1mk*
5797 HP/Apollo 68k Family m68*-apollo*-sysv*,
5799 m68*-hp-bsd*, m68*-hp-hpux*
5800 I960 with MON960 i960-*-coff
5802 * OBSOLETE languages
5804 CHILL, a Pascal like language used by telecommunications companies.
5806 * REMOVED configurations and files
5808 AMD 29k family via UDI a29k-amd-udi, udi29k
5809 A29K VxWorks a29k-*-vxworks
5810 AMD 29000 embedded, using EBMON a29k-none-none
5811 AMD 29000 embedded with COFF a29k-none-coff
5812 AMD 29000 embedded with a.out a29k-none-aout
5814 testsuite/gdb.hp/gdb.threads-hp/ directory
5816 * New command "set max-user-call-depth <nnn>"
5818 This command allows the user to limit the call depth of user-defined
5819 commands. The default is 1024.
5821 * Changes in FreeBSD/i386 native debugging.
5823 Support for the "generate-core-file" has been added.
5825 * New commands "dump", "append", and "restore".
5827 These commands allow data to be copied from target memory
5828 to a bfd-format or binary file (dump and append), and back
5829 from a file into memory (restore).
5831 * Improved "next/step" support on multi-processor Alpha Tru64.
5833 The previous single-step mechanism could cause unpredictable problems,
5834 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5835 of a software single-step mechanism prevents this.
5837 *** Changes in GDB 5.2.1:
5845 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5846 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5847 Fix, by Joel Brobecker imported from mainline.
5849 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5850 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5851 Fix, by Fred Fish, imported from mainline.
5853 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5854 Surprisingly enough, it works now.
5855 By Michal Ludvig, imported from mainline.
5857 i386 hardware watchpoint support:
5858 avoid misses on second run for some targets.
5859 By Pierre Muller, imported from mainline.
5861 *** Changes in GDB 5.2:
5863 * New command "set trust-readonly-sections on[off]".
5865 This command is a hint that tells gdb that read-only sections
5866 really are read-only (ie. that their contents will not change).
5867 In this mode, gdb will go to the object file rather than the
5868 target to read memory from read-only sections (such as ".text").
5869 This can be a significant performance improvement on some
5870 (notably embedded) targets.
5872 * New command "generate-core-file" (or "gcore").
5874 This new gdb command allows the user to drop a core file of the child
5875 process state at any time. So far it's been implemented only for
5876 GNU/Linux and Solaris, but should be relatively easily ported to other
5877 hosts. Argument is core file name (defaults to core.<pid>).
5879 * New command line option
5881 GDB now accepts --pid or -p followed by a process id.
5883 * Change in command line behavior -- corefiles vs. process ids.
5885 There is a subtle behavior in the way in which GDB handles
5886 command line arguments. The first non-flag argument is always
5887 a program to debug, but the second non-flag argument may either
5888 be a corefile or a process id. Previously, GDB would attempt to
5889 open the second argument as a corefile, and if that failed, would
5890 issue a superfluous error message and then attempt to attach it as
5891 a process. Now, if the second argument begins with a non-digit,
5892 it will be treated as a corefile. If it begins with a digit,
5893 GDB will attempt to attach it as a process, and if no such process
5894 is found, will then attempt to open it as a corefile.
5896 * Changes in ARM configurations.
5898 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5899 configuration is fully multi-arch.
5901 * New native configurations
5903 ARM NetBSD arm*-*-netbsd*
5904 x86 OpenBSD i[3456]86-*-openbsd*
5905 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5906 Sparc64 running FreeBSD sparc64-*-freebsd*
5910 Sanyo XStormy16 xstormy16-elf
5912 * OBSOLETE configurations and files
5914 Configurations that have been declared obsolete in this release have
5915 been commented out. Unless there is activity to revive these
5916 configurations, the next release of GDB will have their sources
5917 permanently REMOVED.
5919 AMD 29k family via UDI a29k-amd-udi, udi29k
5920 A29K VxWorks a29k-*-vxworks
5921 AMD 29000 embedded, using EBMON a29k-none-none
5922 AMD 29000 embedded with COFF a29k-none-coff
5923 AMD 29000 embedded with a.out a29k-none-aout
5925 testsuite/gdb.hp/gdb.threads-hp/ directory
5927 * REMOVED configurations and files
5929 TI TMS320C80 tic80-*-*
5931 PowerPC Solaris powerpcle-*-solaris*
5932 PowerPC Windows NT powerpcle-*-cygwin32
5933 PowerPC Netware powerpc-*-netware*
5934 Harris/CXUX m88k m88*-harris-cxux*
5935 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5936 ns32k-utek-sysv* ns32k-utek-*
5937 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5938 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5939 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5940 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5941 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5943 * Changes to command line processing
5945 The new `--args' feature can be used to specify command-line arguments
5946 for the inferior from gdb's command line.
5948 * Changes to key bindings
5950 There is a new `operate-and-get-next' function bound to `C-o'.
5952 *** Changes in GDB 5.1.1
5954 Fix compile problem on DJGPP.
5956 Fix a problem with floating-point registers on the i386 being
5959 Fix to stop GDB crashing on .debug_str debug info.
5961 Numerous documentation fixes.
5963 Numerous testsuite fixes.
5965 *** Changes in GDB 5.1:
5967 * New native configurations
5969 Alpha FreeBSD alpha*-*-freebsd*
5970 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5971 MIPS GNU/Linux mips*-*-linux*
5972 MIPS SGI Irix 6.x mips*-sgi-irix6*
5973 ia64 AIX ia64-*-aix*
5974 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5978 Motorola 68HC11 and 68HC12 m68hc11-elf
5980 UltraSparc running GNU/Linux sparc64-*-linux*
5982 * OBSOLETE configurations and files
5984 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5985 Harris/CXUX m88k m88*-harris-cxux*
5986 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5987 ns32k-utek-sysv* ns32k-utek-*
5988 TI TMS320C80 tic80-*-*
5990 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5991 PowerPC Solaris powerpcle-*-solaris*
5992 PowerPC Windows NT powerpcle-*-cygwin32
5993 PowerPC Netware powerpc-*-netware*
5994 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5995 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5996 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5997 Apple Macintosh (MPW) host N/A
5999 stuff.c (Program to stuff files into a specially prepared space in kdb)
6000 kdb-start.c (Main loop for the standalone kernel debugger)
6002 Configurations that have been declared obsolete in this release have
6003 been commented out. Unless there is activity to revive these
6004 configurations, the next release of GDB will have their sources
6005 permanently REMOVED.
6007 * REMOVED configurations and files
6009 Altos 3068 m68*-altos-*
6010 Convex c1-*-*, c2-*-*
6012 ARM RISCix arm-*-* (as host)
6016 * GDB has been converted to ISO C.
6018 GDB's source code has been converted to ISO C. In particular, the
6019 sources are fully protoized, and rely on standard headers being
6024 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
6026 * The MI enabled by default.
6028 The new machine oriented interface (MI) introduced in GDB 5.0 has been
6029 revised and enabled by default. Packages which use GDB as a debugging
6030 engine behind a UI or another front end are encouraged to switch to
6031 using the GDB/MI interface, instead of the old annotations interface
6032 which is now deprecated.
6034 * Support for debugging Pascal programs.
6036 GDB now includes support for debugging Pascal programs. The following
6037 main features are supported:
6039 - Pascal-specific data types such as sets;
6041 - automatic recognition of Pascal sources based on file-name
6044 - Pascal-style display of data types, variables, and functions;
6046 - a Pascal expression parser.
6048 However, some important features are not yet supported.
6050 - Pascal string operations are not supported at all;
6052 - there are some problems with boolean types;
6054 - Pascal type hexadecimal constants are not supported
6055 because they conflict with the internal variables format;
6057 - support for Pascal objects and classes is not full yet;
6059 - unlike Pascal, GDB is case-sensitive for symbol names.
6061 * Changes in completion.
6063 Commands such as `shell', `run' and `set args', which pass arguments
6064 to inferior programs, now complete on file names, similar to what
6065 users expect at the shell prompt.
6067 Commands which accept locations, such as `disassemble', `print',
6068 `breakpoint', `until', etc. now complete on filenames as well as
6069 program symbols. Thus, if you type "break foob TAB", and the source
6070 files linked into the programs include `foobar.c', that file name will
6071 be one of the candidates for completion. However, file names are not
6072 considered for completion after you typed a colon that delimits a file
6073 name from a name of a function in that file, as in "break foo.c:bar".
6075 `set demangle-style' completes on available demangling styles.
6077 * New platform-independent commands:
6079 It is now possible to define a post-hook for a command as well as a
6080 hook that runs before the command. For more details, see the
6081 documentation of `hookpost' in the GDB manual.
6083 * Changes in GNU/Linux native debugging.
6085 Support for debugging multi-threaded programs has been completely
6086 revised for all platforms except m68k and sparc. You can now debug as
6087 many threads as your system allows you to have.
6089 Attach/detach is supported for multi-threaded programs.
6091 Support for SSE registers was added for x86. This doesn't work for
6092 multi-threaded programs though.
6094 * Changes in MIPS configurations.
6096 Multi-arch support is enabled for all MIPS configurations.
6098 GDB can now be built as native debugger on SGI Irix 6.x systems for
6099 debugging n32 executables. (Debugging 64-bit executables is not yet
6102 * Unified support for hardware watchpoints in all x86 configurations.
6104 Most (if not all) native x86 configurations support hardware-assisted
6105 breakpoints and watchpoints in a unified manner. This support
6106 implements debug register sharing between watchpoints, which allows to
6107 put a virtually infinite number of watchpoints on the same address,
6108 and also supports watching regions up to 16 bytes with several debug
6111 The new maintenance command `maintenance show-debug-regs' toggles
6112 debugging print-outs in functions that insert, remove, and test
6113 watchpoints and hardware breakpoints.
6115 * Changes in the DJGPP native configuration.
6117 New command ``info dos sysinfo'' displays assorted information about
6118 the CPU, OS, memory, and DPMI server.
6120 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
6121 display information about segment descriptors stored in GDT, LDT, and
6124 New commands ``info dos pde'' and ``info dos pte'' display entries
6125 from Page Directory and Page Tables (for now works with CWSDPMI only).
6126 New command ``info dos address-pte'' displays the Page Table entry for
6127 a given linear address.
6129 GDB can now pass command lines longer than 126 characters to the
6130 program being debugged (requires an update to the libdbg.a library
6131 which is part of the DJGPP development kit).
6133 DWARF2 debug info is now supported.
6135 It is now possible to `step' and `next' through calls to `longjmp'.
6137 * Changes in documentation.
6139 All GDB documentation was converted to GFDL, the GNU Free
6140 Documentation License.
6142 Tracepoints-related commands are now fully documented in the GDB
6145 TUI, the Text-mode User Interface, is now documented in the manual.
6147 Tracepoints-related commands are now fully documented in the GDB
6150 The "GDB Internals" manual now has an index. It also includes
6151 documentation of `ui_out' functions, GDB coding standards, x86
6152 hardware watchpoints, and memory region attributes.
6154 * GDB's version number moved to ``version.in''
6156 The Makefile variable VERSION has been replaced by the file
6157 ``version.in''. People creating GDB distributions should update the
6158 contents of this file.
6162 GUD support is now a standard part of the EMACS distribution.
6164 *** Changes in GDB 5.0:
6166 * Improved support for debugging FP programs on x86 targets
6168 Unified and much-improved support for debugging floating-point
6169 programs on all x86 targets. In particular, ``info float'' now
6170 displays the FP registers in the same format on all x86 targets, with
6171 greater level of detail.
6173 * Improvements and bugfixes in hardware-assisted watchpoints
6175 It is now possible to watch array elements, struct members, and
6176 bitfields with hardware-assisted watchpoints. Data-read watchpoints
6177 on x86 targets no longer erroneously trigger when the address is
6180 * Improvements in the native DJGPP version of GDB
6182 The distribution now includes all the scripts and auxiliary files
6183 necessary to build the native DJGPP version on MS-DOS/MS-Windows
6184 machines ``out of the box''.
6186 The DJGPP version can now debug programs that use signals. It is
6187 possible to catch signals that happened in the debuggee, deliver
6188 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
6189 would kill the program being debugged.) Programs that hook hardware
6190 interrupts (keyboard, timer, etc.) can also be debugged.
6192 It is now possible to debug DJGPP programs that redirect their
6193 standard handles or switch them to raw (as opposed to cooked) mode, or
6194 even close them. The command ``run < foo > bar'' works as expected,
6195 and ``info terminal'' reports useful information about the debuggee's
6196 terminal, including raw/cooked mode, redirection, etc.
6198 The DJGPP version now uses termios functions for console I/O, which
6199 enables debugging graphics programs. Interrupting GDB with Ctrl-C
6202 DOS-style file names with drive letters are now fully supported by
6205 It is now possible to debug DJGPP programs that switch their working
6206 directory. It is also possible to rerun the debuggee any number of
6207 times without restarting GDB; thus, you can use the same setup,
6208 breakpoints, etc. for many debugging sessions.
6210 * New native configurations
6212 ARM GNU/Linux arm*-*-linux*
6213 PowerPC GNU/Linux powerpc-*-linux*
6217 Motorola MCore mcore-*-*
6218 x86 VxWorks i[3456]86-*-vxworks*
6219 PowerPC VxWorks powerpc-*-vxworks*
6220 TI TMS320C80 tic80-*-*
6222 * OBSOLETE configurations
6224 Altos 3068 m68*-altos-*
6225 Convex c1-*-*, c2-*-*
6227 ARM RISCix arm-*-* (as host)
6230 Configurations that have been declared obsolete will be commented out,
6231 but the code will be left in place. If there is no activity to revive
6232 these configurations before the next release of GDB, the sources will
6233 be permanently REMOVED.
6235 * Gould support removed
6237 Support for the Gould PowerNode and NP1 has been removed.
6239 * New features for SVR4
6241 On SVR4 native platforms (such as Solaris), if you attach to a process
6242 without first loading a symbol file, GDB will now attempt to locate and
6243 load symbols from the running process's executable file.
6245 * Many C++ enhancements
6247 C++ support has been greatly improved. Overload resolution now works properly
6248 in almost all cases. RTTI support is on the way.
6250 * Remote targets can connect to a sub-program
6252 A popen(3) style serial-device has been added. This device starts a
6253 sub-process (such as a stand-alone simulator) and then communicates
6254 with that. The sub-program to run is specified using the syntax
6255 ``|<program> <args>'' vis:
6257 (gdb) set remotedebug 1
6258 (gdb) target extended-remote |mn10300-elf-sim program-args
6260 * MIPS 64 remote protocol
6262 A long standing bug in the mips64 remote protocol where by GDB
6263 expected certain 32 bit registers (ex SR) to be transfered as 32
6264 instead of 64 bits has been fixed.
6266 The command ``set remote-mips64-transfers-32bit-regs on'' has been
6267 added to provide backward compatibility with older versions of GDB.
6269 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
6271 The command ``set remotebinarydownload'' command has been replaced by
6272 ``set remote X-packet''. Other commands in ``set remote'' family
6273 include ``set remote P-packet''.
6275 * Breakpoint commands accept ranges.
6277 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
6278 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
6279 ``tracepoint passcount'' also accepts a range of tracepoints.
6281 * ``apropos'' command added.
6283 The ``apropos'' command searches through command names and
6284 documentation strings, printing out matches, making it much easier to
6285 try to find a command that does what you are looking for.
6289 A new machine oriented interface (MI) has been added to GDB. This
6290 interface is designed for debug environments running GDB as a separate
6291 process. This is part of the long term libGDB project. See the
6292 "GDB/MI" chapter of the GDB manual for further information. It can be
6293 enabled by configuring with:
6295 .../configure --enable-gdbmi
6297 *** Changes in GDB-4.18:
6299 * New native configurations
6301 HP-UX 10.20 hppa*-*-hpux10.20
6302 HP-UX 11.x hppa*-*-hpux11.0*
6303 M68K GNU/Linux m68*-*-linux*
6307 Fujitsu FR30 fr30-*-elf*
6308 Intel StrongARM strongarm-*-*
6309 Mitsubishi D30V d30v-*-*
6311 * OBSOLETE configurations
6313 Gould PowerNode, NP1 np1-*-*, pn-*-*
6315 Configurations that have been declared obsolete will be commented out,
6316 but the code will be left in place. If there is no activity to revive
6317 these configurations before the next release of GDB, the sources will
6318 be permanently REMOVED.
6322 As a compatibility experiment, GDB's source files buildsym.h and
6323 buildsym.c have been converted to pure standard C, no longer
6324 containing any K&R compatibility code. We believe that all systems in
6325 use today either come with a standard C compiler, or have a GCC port
6326 available. If this is not true, please report the affected
6327 configuration to bug-gdb@gnu.org immediately. See the README file for
6328 information about getting a standard C compiler if you don't have one
6333 GDB now uses readline 2.2.
6335 * set extension-language
6337 You can now control the mapping between filename extensions and source
6338 languages by using the `set extension-language' command. For instance,
6339 you can ask GDB to treat .c files as C++ by saying
6340 set extension-language .c c++
6341 The command `info extensions' lists all of the recognized extensions
6342 and their associated languages.
6344 * Setting processor type for PowerPC and RS/6000
6346 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
6347 you can use the `set processor' command to specify what variant of the
6348 PowerPC family you are debugging. The command
6352 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
6353 following PowerPC and RS6000 variants:
6355 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
6356 rs6000 IBM RS6000 ("POWER") architecture, user-level view
6358 403GC IBM PowerPC 403GC
6359 505 Motorola PowerPC 505
6360 860 Motorola PowerPC 860 or 850
6361 601 Motorola PowerPC 601
6362 602 Motorola PowerPC 602
6363 603 Motorola/IBM PowerPC 603 or 603e
6364 604 Motorola PowerPC 604 or 604e
6365 750 Motorola/IBM PowerPC 750 or 750
6367 At the moment, this command just tells GDB what to name the
6368 special-purpose processor registers. Since almost all the affected
6369 registers are inaccessible to user-level programs, this command is
6370 only useful for remote debugging in its present form.
6374 Thanks to a major code donation from Hewlett-Packard, GDB now has much
6375 more extensive support for HP-UX. Added features include shared
6376 library support, kernel threads and hardware watchpoints for 11.00,
6377 support for HP's ANSI C and C++ compilers, and a compatibility mode
6378 for xdb and dbx commands.
6382 HP's donation includes the new concept of catchpoints, which is a
6383 generalization of the old catch command. On HP-UX, it is now possible
6384 to catch exec, fork, and vfork, as well as library loading.
6386 This means that the existing catch command has changed; its first
6387 argument now specifies the type of catch to be set up. See the
6388 output of "help catch" for a list of catchpoint types.
6390 * Debugging across forks
6392 On HP-UX, you can choose which process to debug when a fork() happens
6397 HP has donated a curses-based terminal user interface (TUI). To get
6398 it, build with --enable-tui. Although this can be enabled for any
6399 configuration, at present it only works for native HP debugging.
6401 * GDB remote protocol additions
6403 A new protocol packet 'X' that writes binary data is now available.
6404 Default behavior is to try 'X', then drop back to 'M' if the stub
6405 fails to respond. The settable variable `remotebinarydownload'
6406 allows explicit control over the use of 'X'.
6408 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
6409 full 64-bit address. The command
6411 set remoteaddresssize 32
6413 can be used to revert to the old behaviour. For existing remote stubs
6414 the change should not be noticed, as the additional address information
6417 In order to assist in debugging stubs, you may use the maintenance
6418 command `packet' to send any text string to the stub. For instance,
6420 maint packet heythere
6422 sends the packet "$heythere#<checksum>". Note that it is very easy to
6423 disrupt a debugging session by sending the wrong packet at the wrong
6426 The compare-sections command allows you to compare section data on the
6427 target to what is in the executable file without uploading or
6428 downloading, by comparing CRC checksums.
6430 * Tracing can collect general expressions
6432 You may now collect general expressions at tracepoints. This requires
6433 further additions to the target-side stub; see tracepoint.c and
6434 doc/agentexpr.texi for further details.
6436 * mask-address variable for Mips
6438 For Mips targets, you may control the zeroing of the upper 32 bits of
6439 a 64-bit address by entering `set mask-address on'. This is mainly
6440 of interest to users of embedded R4xxx and R5xxx processors.
6442 * Higher serial baud rates
6444 GDB's serial code now allows you to specify baud rates 57600, 115200,
6445 230400, and 460800 baud. (Note that your host system may not be able
6446 to achieve all of these rates.)
6450 The i960 configuration now includes an initial implementation of a
6451 builtin simulator, contributed by Jim Wilson.
6454 *** Changes in GDB-4.17:
6456 * New native configurations
6458 Alpha GNU/Linux alpha*-*-linux*
6459 Unixware 2.x i[3456]86-unixware2*
6460 Irix 6.x mips*-sgi-irix6*
6461 PowerPC GNU/Linux powerpc-*-linux*
6462 PowerPC Solaris powerpcle-*-solaris*
6463 Sparc GNU/Linux sparc-*-linux*
6464 Motorola sysV68 R3V7.1 m68k-motorola-sysv
6468 Argonaut Risc Chip (ARC) arc-*-*
6469 Hitachi H8/300S h8300*-*-*
6470 Matsushita MN10200 w/simulator mn10200-*-*
6471 Matsushita MN10300 w/simulator mn10300-*-*
6472 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
6473 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
6474 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
6475 Mitsubishi D10V w/simulator d10v-*-*
6476 Mitsubishi M32R/D w/simulator m32r-*-elf*
6477 Tsqware Sparclet sparclet-*-*
6478 NEC V850 w/simulator v850-*-*
6480 * New debugging protocols
6482 ARM with RDI protocol arm*-*-*
6483 M68K with dBUG monitor m68*-*-{aout,coff,elf}
6484 DDB and LSI variants of PMON protocol mips*-*-*
6485 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
6486 PowerPC with SDS protocol powerpc{,le}-*-eabi
6487 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6491 All configurations can now understand and use the DWARF 2 debugging
6492 format. The choice is automatic, if the symbol file contains DWARF 2
6497 GDB now includes basic Java language support. This support is
6498 only useful with Java compilers that produce native machine code.
6500 * solib-absolute-prefix and solib-search-path
6502 For SunOS and SVR4 shared libraries, you may now set the prefix for
6503 loading absolute shared library symbol files, and the search path for
6504 locating non-absolute shared library symbol files.
6506 * Live range splitting
6508 GDB can now effectively debug code for which GCC has performed live
6509 range splitting as part of its optimization. See gdb/doc/LRS for
6510 more details on the expected format of the stabs information.
6514 GDB's support for the GNU Hurd, including thread debugging, has been
6515 updated to work with current versions of the Hurd.
6519 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6520 instruction set. ARM GDB automatically detects when Thumb
6521 instructions are in use, and adjusts disassembly and backtracing
6526 GDB's MIPS target configurations now handle the MIP16 16-bit
6531 GDB now includes support for overlays; if an executable has been
6532 linked such that multiple sections are based at the same address, GDB
6533 will decide which section to use for symbolic info. You can choose to
6534 control the decision manually, using overlay commands, or implement
6535 additional target-side support and use "overlay load-target" to bring
6536 in the overlay mapping. Do "help overlay" for more detail.
6540 The command "info symbol <address>" displays information about
6541 the symbol at the specified address.
6545 The standard remote protocol now includes an extension that allows
6546 asynchronous collection and display of trace data. This requires
6547 extensive support in the target-side debugging stub. Tracing mode
6548 includes a new interaction mode in GDB and new commands: see the
6549 file tracepoint.c for more details.
6553 Configurations for embedded MIPS now include a simulator contributed
6554 by Cygnus Solutions. The simulator supports the instruction sets
6555 of most MIPS variants.
6559 Sparc configurations may now include the ERC32 simulator contributed
6560 by the European Space Agency. The simulator is not built into
6561 Sparc targets by default; configure with --enable-sim to include it.
6565 For target configurations that may include multiple variants of a
6566 basic architecture (such as MIPS and SH), you may now set the
6567 architecture explicitly. "set arch" sets, "info arch" lists
6568 the possible architectures.
6570 *** Changes in GDB-4.16:
6572 * New native configurations
6574 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6575 M68K NetBSD m68k-*-netbsd*
6576 PowerPC AIX 4.x powerpc-*-aix*
6577 PowerPC MacOS powerpc-*-macos*
6578 PowerPC Windows NT powerpcle-*-cygwin32
6579 RS/6000 AIX 4.x rs6000-*-aix4*
6583 ARM with RDP protocol arm-*-*
6584 I960 with MON960 i960-*-coff
6585 MIPS VxWorks mips*-*-vxworks*
6586 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6587 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6589 Matra Sparclet sparclet-*-*
6593 The powerpc-eabi configuration now includes the PSIM simulator,
6594 contributed by Andrew Cagney, with assistance from Mike Meissner.
6595 PSIM is a very elaborate model of the PowerPC, including not only
6596 basic instruction set execution, but also details of execution unit
6597 performance and I/O hardware. See sim/ppc/README for more details.
6601 GDB now works with Solaris 2.5.
6603 * Windows 95/NT native
6605 GDB will now work as a native debugger on Windows 95 and Windows NT.
6606 To build it from source, you must use the "gnu-win32" environment,
6607 which uses a DLL to emulate enough of Unix to run the GNU tools.
6608 Further information, binaries, and sources are available at
6609 ftp.cygnus.com, under pub/gnu-win32.
6611 * dont-repeat command
6613 If a user-defined command includes the command `dont-repeat', then the
6614 command will not be repeated if the user just types return. This is
6615 useful if the command is time-consuming to run, so that accidental
6616 extra keystrokes don't run the same command many times.
6618 * Send break instead of ^C
6620 The standard remote protocol now includes an option to send a break
6621 rather than a ^C to the target in order to interrupt it. By default,
6622 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6624 * Remote protocol timeout
6626 The standard remote protocol includes a new variable `remotetimeout'
6627 that allows you to set the number of seconds before GDB gives up trying
6628 to read from the target. The default value is 2.
6630 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6632 By default GDB will automatically keep track of objects as they are
6633 loaded and unloaded by the dynamic linker. By using the command `set
6634 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6635 when shared library events occur, thus allowing you to set breakpoints
6636 in shared libraries which are explicitly loaded by the inferior.
6638 Note this feature does not work on hpux8. On hpux9 you must link
6639 /usr/lib/end.o into your program. This feature should work
6640 automatically on hpux10.
6642 * Irix 5.x hardware watchpoint support
6644 Irix 5 configurations now support the use of hardware watchpoints.
6646 * Mips protocol "SYN garbage limit"
6648 When debugging a Mips target using the `target mips' protocol, you
6649 may set the number of characters that GDB will ignore by setting
6650 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6651 every character. The default value is 1050.
6653 * Recording and replaying remote debug sessions
6655 If you set `remotelogfile' to the name of a file, gdb will write to it
6656 a recording of a remote debug session. This recording may then be
6657 replayed back to gdb using "gdbreplay". See gdbserver/README for
6658 details. This is useful when you have a problem with GDB while doing
6659 remote debugging; you can make a recording of the session and send it
6660 to someone else, who can then recreate the problem.
6662 * Speedups for remote debugging
6664 GDB includes speedups for downloading and stepping MIPS systems using
6665 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6666 and more efficient S-record downloading.
6668 * Memory use reductions and statistics collection
6670 GDB now uses less memory and reports statistics about memory usage.
6671 Try the `maint print statistics' command, for example.
6673 *** Changes in GDB-4.15:
6675 * Psymtabs for XCOFF
6677 The symbol reader for AIX GDB now uses partial symbol tables. This
6678 can greatly improve startup time, especially for large executables.
6680 * Remote targets use caching
6682 Remote targets now use a data cache to speed up communication with the
6683 remote side. The data cache could lead to incorrect results because
6684 it doesn't know about volatile variables, thus making it impossible to
6685 debug targets which use memory mapped I/O devices. `set remotecache
6686 off' turns the data cache off.
6688 * Remote targets may have threads
6690 The standard remote protocol now includes support for multiple threads
6691 in the target system, using new protocol commands 'H' and 'T'. See
6692 gdb/remote.c for details.
6696 If GDB is configured with `--enable-netrom', then it will include
6697 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6698 acts as though it is a bank of ROM on the target board, but you can
6699 write into it over the network. GDB's support consists only of
6700 support for fast loading into the emulated ROM; to debug, you must use
6701 another protocol, such as standard remote protocol. The usual
6702 sequence is something like
6704 target nrom <netrom-hostname>
6706 target remote <netrom-hostname>:1235
6710 GDB now includes support for the Apple Macintosh, as a host only. It
6711 may be run as either an MPW tool or as a standalone application, and
6712 it can debug through the serial port. All the usual GDB commands are
6713 available, but to the target command, you must supply "serial" as the
6714 device type instead of "/dev/ttyXX". See mpw-README in the main
6715 directory for more information on how to build. The MPW configuration
6716 scripts */mpw-config.in support only a few targets, and only the
6717 mips-idt-ecoff target has been tested.
6721 GDB configuration now uses autoconf. This is not user-visible,
6722 but does simplify configuration and building.
6726 GDB now supports hpux10.
6728 *** Changes in GDB-4.14:
6730 * New native configurations
6732 x86 FreeBSD i[345]86-*-freebsd
6733 x86 NetBSD i[345]86-*-netbsd
6734 NS32k NetBSD ns32k-*-netbsd
6735 Sparc NetBSD sparc-*-netbsd
6739 A29K VxWorks a29k-*-vxworks
6740 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6741 CPU32 EST-300 emulator m68*-*-est*
6742 PowerPC ELF powerpc-*-elf
6745 * Alpha OSF/1 support for procfs
6747 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6748 possible to attach to running processes. As the mounting of the /proc
6749 filesystem is optional on the Alpha, GDB automatically determines
6750 the availability of /proc during startup. This can lead to problems
6751 if /proc is unmounted after GDB has been started.
6753 * Arguments to user-defined commands
6755 User commands may accept up to 10 arguments separated by whitespace.
6756 Arguments are accessed within the user command via $arg0..$arg9. A
6759 print $arg0 + $arg1 + $arg2
6761 To execute the command use:
6764 Defines the command "adder" which prints the sum of its three arguments.
6765 Note the arguments are text substitutions, so they may reference variables,
6766 use complex expressions, or even perform inferior function calls.
6768 * New `if' and `while' commands
6770 This makes it possible to write more sophisticated user-defined
6771 commands. Both commands take a single argument, which is the
6772 expression to evaluate, and must be followed by the commands to
6773 execute, one per line, if the expression is nonzero, the list being
6774 terminated by the word `end'. The `if' command list may include an
6775 `else' word, which causes the following commands to be executed only
6776 if the expression is zero.
6778 * Fortran source language mode
6780 GDB now includes partial support for Fortran 77. It will recognize
6781 Fortran programs and can evaluate a subset of Fortran expressions, but
6782 variables and functions may not be handled correctly. GDB will work
6783 with G77, but does not yet know much about symbols emitted by other
6786 * Better HPUX support
6788 Most debugging facilities now work on dynamic executables for HPPAs
6789 running hpux9 or later. You can attach to running dynamically linked
6790 processes, but by default the dynamic libraries will be read-only, so
6791 for instance you won't be able to put breakpoints in them. To change
6792 that behavior do the following before running the program:
6798 This will cause the libraries to be mapped private and read-write.
6799 To revert to the normal behavior, do this:
6805 You cannot set breakpoints or examine data in the library until after
6806 the library is loaded if the function/data symbols do not have
6809 GDB can now also read debug symbols produced by the HP C compiler on
6810 HPPAs (sorry, no C++, Fortran or 68k support).
6812 * Target byte order now dynamically selectable
6814 You can choose which byte order to use with a target system, via the
6815 commands "set endian big" and "set endian little", and you can see the
6816 current setting by using "show endian". You can also give the command
6817 "set endian auto", in which case GDB will use the byte order
6818 associated with the executable. Currently, only embedded MIPS
6819 configurations support dynamic selection of target byte order.
6821 * New DOS host serial code
6823 This version uses DPMI interrupts to handle buffered I/O, so you
6824 no longer need to run asynctsr when debugging boards connected to
6827 *** Changes in GDB-4.13:
6829 * New "complete" command
6831 This lists all the possible completions for the rest of the line, if it
6832 were to be given as a command itself. This is intended for use by emacs.
6834 * Trailing space optional in prompt
6836 "set prompt" no longer adds a space for you after the prompt you set. This
6837 allows you to set a prompt which ends in a space or one that does not.
6839 * Breakpoint hit counts
6841 "info break" now displays a count of the number of times the breakpoint
6842 has been hit. This is especially useful in conjunction with "ignore"; you
6843 can ignore a large number of breakpoint hits, look at the breakpoint info
6844 to see how many times the breakpoint was hit, then run again, ignoring one
6845 less than that number, and this will get you quickly to the last hit of
6848 * Ability to stop printing at NULL character
6850 "set print null-stop" will cause GDB to stop printing the characters of
6851 an array when the first NULL is encountered. This is useful when large
6852 arrays actually contain only short strings.
6854 * Shared library breakpoints
6856 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6857 breakpoints in shared libraries before the executable is run.
6859 * Hardware watchpoints
6861 There is a new hardware breakpoint for the watch command for sparclite
6862 targets. See gdb/sparclite/hw_breakpoint.note.
6864 Hardware watchpoints are also now supported under GNU/Linux.
6868 Annotations have been added. These are for use with graphical interfaces,
6869 and are still experimental. Currently only gdba.el uses these.
6871 * Improved Irix 5 support
6873 GDB now works properly with Irix 5.2.
6875 * Improved HPPA support
6877 GDB now works properly with the latest GCC and GAS.
6879 * New native configurations
6881 Sequent PTX4 i[34]86-sequent-ptx4
6882 HPPA running OSF/1 hppa*-*-osf*
6883 Atari TT running SVR4 m68*-*-sysv4*
6884 RS/6000 LynxOS rs6000-*-lynxos*
6888 OS/9000 i[34]86-*-os9k
6889 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6892 * Hitachi SH7000 and E7000-PC ICE support
6894 There is now support for communicating with the Hitachi E7000-PC ICE.
6895 This is available automatically when GDB is configured for the SH.
6899 As usual, a variety of small fixes and improvements, both generic
6900 and configuration-specific. See the ChangeLog for more detail.
6902 *** Changes in GDB-4.12:
6904 * Irix 5 is now supported
6908 GDB-4.12 on the HPPA has a number of changes which make it unable
6909 to debug the output from the currently released versions of GCC and
6910 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6911 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6912 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6915 *** Changes in GDB-4.11:
6917 * User visible changes:
6921 The "set remotedebug" option is now consistent between the mips remote
6922 target, remote targets using the gdb-specific protocol, UDI (AMD's
6923 debug protocol for the 29k) and the 88k bug monitor. It is now an
6924 integer specifying a debug level (normally 0 or 1, but 2 means more
6925 debugging info for the mips target).
6927 * DEC Alpha native support
6929 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6930 debug info, but GDB works fairly well with the DEC compiler and should
6931 work with a future GCC release. See the README file for a few
6932 Alpha-specific notes.
6934 * Preliminary thread implementation
6936 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6938 * LynxOS native and target support for 386
6940 This release has been hosted on LynxOS 2.2, and also can be configured
6941 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6944 * Improvements in C++ mangling/demangling.
6946 This release has much better g++ debugging, specifically in name
6947 mangling/demangling, virtual function calls, print virtual table,
6948 call methods, ...etc.
6950 *** Changes in GDB-4.10:
6952 * User visible changes:
6954 Remote debugging using the GDB-specific (`target remote') protocol now
6955 supports the `load' command. This is only useful if you have some
6956 other way of getting the stub to the target system, and you can put it
6957 somewhere in memory where it won't get clobbered by the download.
6959 Filename completion now works.
6961 When run under emacs mode, the "info line" command now causes the
6962 arrow to point to the line specified. Also, "info line" prints
6963 addresses in symbolic form (as well as hex).
6965 All vxworks based targets now support a user settable option, called
6966 vxworks-timeout. This option represents the number of seconds gdb
6967 should wait for responses to rpc's. You might want to use this if
6968 your vxworks target is, perhaps, a slow software simulator or happens
6969 to be on the far side of a thin network line.
6973 This release contains support for using a DEC alpha as a GDB host for
6974 cross debugging. Native alpha debugging is not supported yet.
6977 *** Changes in GDB-4.9:
6981 This is the first GDB release which is accompanied by a matching testsuite.
6982 The testsuite requires installation of dejagnu, which should be available
6983 via ftp from most sites that carry GNU software.
6987 'Cfront' style demangling has had its name changed to 'ARM' style, to
6988 emphasize that it was written from the specifications in the C++ Annotated
6989 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6990 disclaimers, it still generated too much confusion with users attempting to
6991 use gdb with AT&T cfront.
6995 GDB now uses a standard remote interface to a simulator library.
6996 So far, the library contains simulators for the Zilog Z8001/2, the
6997 Hitachi H8/300, H8/500 and Super-H.
6999 * New targets supported
7001 H8/300 simulator h8300-hitachi-hms or h8300hms
7002 H8/500 simulator h8500-hitachi-hms or h8500hms
7003 SH simulator sh-hitachi-hms or sh
7004 Z8000 simulator z8k-zilog-none or z8ksim
7005 IDT MIPS board over serial line mips-idt-ecoff
7007 Cross-debugging to GO32 targets is supported. It requires a custom
7008 version of the i386-stub.c module which is integrated with the
7009 GO32 memory extender.
7011 * New remote protocols
7013 MIPS remote debugging protocol.
7015 * New source languages supported
7017 This version includes preliminary support for Chill, a Pascal like language
7018 used by telecommunications companies. Chill support is also being integrated
7019 into the GNU compiler, but we don't know when it will be publically available.
7022 *** Changes in GDB-4.8:
7024 * HP Precision Architecture supported
7026 GDB now supports HP PA-RISC machines running HPUX. A preliminary
7027 version of this support was available as a set of patches from the
7028 University of Utah. GDB does not support debugging of programs
7029 compiled with the HP compiler, because HP will not document their file
7030 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
7031 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
7033 Many problems in the preliminary version have been fixed.
7035 * Faster and better demangling
7037 We have improved template demangling and fixed numerous bugs in the GNU style
7038 demangler. It can now handle type modifiers such as `static' or `const'. Wide
7039 character types (wchar_t) are now supported. Demangling of each symbol is now
7040 only done once, and is cached when the symbol table for a file is read in.
7041 This results in a small increase in memory usage for C programs, a moderate
7042 increase in memory usage for C++ programs, and a fantastic speedup in
7045 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
7046 from the specifications in the Annotated Reference Manual, which AT&T's
7047 compiler does not actually implement.
7049 * G++ multiple inheritance compiler problem
7051 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
7052 inheritance lattices was reworked to properly discover ambiguities. We
7053 recently found an example which causes this new algorithm to fail in a
7054 very subtle way, producing bad debug information for those classes.
7055 The file 'gcc.patch' (in this directory) can be applied to gcc to
7056 circumvent the problem. A future GCC release will contain a complete
7059 The previous G++ debug info problem (mentioned below for the gdb-4.7
7060 release) is fixed in gcc version 2.3.2.
7062 * Improved configure script
7064 The `configure' script will now attempt to guess your system type if
7065 you don't supply a host system type. The old scheme of supplying a
7066 host system triplet is preferable over using this. All the magic is
7067 done in the new `config.guess' script. Examine it for details.
7069 We have also brought our configure script much more in line with the FSF's
7070 version. It now supports the --with-xxx options. In particular,
7071 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
7072 The resulting GDB will not be able to read arbitrary object file formats --
7073 only the format ``expected'' to be used on the configured target system.
7074 We hope to make this the default in a future release.
7076 * Documentation improvements
7078 There's new internal documentation on how to modify GDB, and how to
7079 produce clean changes to the code. We implore people to read it
7080 before submitting changes.
7082 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
7083 M4 macros. The new texinfo.tex is provided in this release. Pre-built
7084 `info' files are also provided. To build `info' files from scratch,
7085 you will need the latest `makeinfo' release, which will be available in
7086 a future texinfo-X.Y release.
7088 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
7089 We're not sure exactly which versions have this problem, but it has
7090 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
7091 or better. If that isn't possible, there is a patch in
7092 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
7093 around this problem.
7097 GDB now supports array constants that can be used in expressions typed in by
7098 the user. The syntax is `{element, element, ...}'. Ie: you can now type
7099 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
7102 The new directory `gdb/sparclite' contains a program that demonstrates
7103 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
7105 * New native hosts supported
7107 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
7108 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
7110 * New targets supported
7112 AMD 29k family via UDI a29k-amd-udi or udi29k
7114 * New file formats supported
7116 BFD now supports reading HP/PA-RISC executables (SOM file format?),
7117 HPUX core files, and SCO 3.2v2 core files.
7121 Attaching to processes now works again; thanks for the many bug reports.
7123 We have also stomped on a bunch of core dumps caused by
7124 printf_filtered("%s") problems.
7126 We eliminated a copyright problem on the rpc and ptrace header files
7127 for VxWorks, which was discovered at the last minute during the 4.7
7128 release. You should now be able to build a VxWorks GDB.
7130 You can now interrupt gdb while an attached process is running. This
7131 will cause the attached process to stop, and give control back to GDB.
7133 We fixed problems caused by using too many file descriptors
7134 for reading symbols from object files and libraries. This was
7135 especially a problem for programs that used many (~100) shared
7138 The `step' command now only enters a subroutine if there is line number
7139 information for the subroutine. Otherwise it acts like the `next'
7140 command. Previously, `step' would enter subroutines if there was
7141 any debugging information about the routine. This avoids problems
7142 when using `cc -g1' on MIPS machines.
7144 * Internal improvements
7146 GDB's internal interfaces have been improved to make it easier to support
7147 debugging of multiple languages in the future.
7149 GDB now uses a common structure for symbol information internally.
7150 Minimal symbols (derived from linkage symbols in object files), partial
7151 symbols (from a quick scan of debug information), and full symbols
7152 contain a common subset of information, making it easier to write
7153 shared code that handles any of them.
7155 * New command line options
7157 We now accept --silent as an alias for --quiet.
7161 The memory-mapped-malloc library is now licensed under the GNU Library
7162 General Public License.
7164 *** Changes in GDB-4.7:
7166 * Host/native/target split
7168 GDB has had some major internal surgery to untangle the support for
7169 hosts and remote targets. Now, when you configure GDB for a remote
7170 target, it will no longer load in all of the support for debugging
7171 local programs on the host. When fully completed and tested, this will
7172 ensure that arbitrary host/target combinations are possible.
7174 The primary conceptual shift is to separate the non-portable code in
7175 GDB into three categories. Host specific code is required any time GDB
7176 is compiled on that host, regardless of the target. Target specific
7177 code relates to the peculiarities of the target, but can be compiled on
7178 any host. Native specific code is everything else: it can only be
7179 built when the host and target are the same system. Child process
7180 handling and core file support are two common `native' examples.
7182 GDB's use of /proc for controlling Unix child processes is now cleaner.
7183 It has been split out into a single module under the `target_ops' vector,
7184 plus two native-dependent functions for each system that uses /proc.
7186 * New hosts supported
7188 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
7189 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7190 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
7192 * New targets supported
7194 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
7195 68030 and CPU32 m68030-*-*, m68332-*-*
7197 * New native hosts supported
7199 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7200 (386bsd is not well tested yet)
7201 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
7203 * New file formats supported
7205 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
7206 supports reading of `a.out.adobe' object files, which are an a.out
7207 format extended with minimal information about multiple sections.
7211 `show copying' is the same as the old `info copying'.
7212 `show warranty' is the same as `info warrantee'.
7213 These were renamed for consistency. The old commands continue to work.
7215 `info handle' is a new alias for `info signals'.
7217 You can now define pre-command hooks, which attach arbitrary command
7218 scripts to any command. The commands in the hook will be executed
7219 prior to the user's command. You can also create a hook which will be
7220 executed whenever the program stops. See gdb.texinfo.
7224 We now deal with Cfront style name mangling, and can even extract type
7225 info from mangled symbols. GDB can automatically figure out which
7226 symbol mangling style your C++ compiler uses.
7228 Calling of methods and virtual functions has been improved as well.
7232 The crash that occurred when debugging Sun Ansi-C compiled binaries is
7233 fixed. This was due to mishandling of the extra N_SO stabs output
7236 We also finally got Ultrix 4.2 running in house, and fixed core file
7237 support, with help from a dozen people on the net.
7239 John M. Farrell discovered that the reason that single-stepping was so
7240 slow on all of the Mips based platforms (primarily SGI and DEC) was
7241 that we were trying to demangle and lookup a symbol used for internal
7242 purposes on every instruction that was being stepped through. Changing
7243 the name of that symbol so that it couldn't be mistaken for a C++
7244 mangled symbol sped things up a great deal.
7246 Rich Pixley sped up symbol lookups in general by getting much smarter
7247 about when C++ symbol mangling is necessary. This should make symbol
7248 completion (TAB on the command line) much faster. It's not as fast as
7249 we'd like, but it's significantly faster than gdb-4.6.
7253 A new user controllable variable 'call_scratch_address' can
7254 specify the location of a scratch area to be used when GDB
7255 calls a function in the target. This is necessary because the
7256 usual method of putting the scratch area on the stack does not work
7257 in systems that have separate instruction and data spaces.
7259 We integrated changes to support the 29k UDI (Universal Debugger
7260 Interface), but discovered at the last minute that we didn't have all
7261 of the appropriate copyright paperwork. We are working with AMD to
7262 resolve this, and hope to have it available soon.
7266 We have sped up the remote serial line protocol, especially for targets
7267 with lots of registers. It now supports a new `expedited status' ('T')
7268 message which can be used in place of the existing 'S' status message.
7269 This allows the remote stub to send only the registers that GDB
7270 needs to make a quick decision about single-stepping or conditional
7271 breakpoints, eliminating the need to fetch the entire register set for
7272 each instruction being stepped through.
7274 The GDB remote serial protocol now implements a write-through cache for
7275 registers, only re-reading the registers if the target has run.
7277 There is also a new remote serial stub for SPARC processors. You can
7278 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
7279 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
7280 processor with a serial port.
7284 Configure.in files have become much easier to read and modify. A new
7285 `table driven' format makes it more obvious what configurations are
7286 supported, and what files each one uses.
7290 There is a new opcodes library which will eventually contain all of the
7291 disassembly routines and opcode tables. At present, it only contains
7292 Sparc and Z8000 routines. This will allow the assembler, debugger, and
7293 disassembler (binutils/objdump) to share these routines.
7295 The libiberty library is now copylefted under the GNU Library General
7296 Public License. This allows more liberal use, and was done so libg++
7297 can use it. This makes no difference to GDB, since the Library License
7298 grants all the rights from the General Public License.
7302 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
7303 reference to the stabs symbol info used by the debugger. It is (as far
7304 as we know) the only published document on this fascinating topic. We
7305 encourage you to read it, compare it to the stabs information on your
7306 system, and send improvements on the document in general (to
7307 bug-gdb@prep.ai.mit.edu).
7309 And, of course, many bugs have been fixed.
7312 *** Changes in GDB-4.6:
7314 * Better support for C++ function names
7316 GDB now accepts as input the "demangled form" of C++ overloaded function
7317 names and member function names, and can do command completion on such names
7318 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
7319 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
7320 Make use of command completion, it is your friend.
7322 GDB also now accepts a variety of C++ mangled symbol formats. They are
7323 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
7324 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
7325 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
7326 for the list of formats.
7328 * G++ symbol mangling problem
7330 Recent versions of gcc have a bug in how they emit debugging information for
7331 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
7332 directory) can be applied to gcc to fix the problem. Alternatively, if you
7333 can't fix gcc, you can #define GCC_MANGLE_BUG when compiling gdb/symtab.c. The
7334 usual symptom is difficulty with setting breakpoints on methods. GDB complains
7335 about the method being non-existent. (We believe that version 2.2.2 of GCC has
7338 * New 'maintenance' command
7340 All of the commands related to hacking GDB internals have been moved out of
7341 the main command set, and now live behind the 'maintenance' command. This
7342 can also be abbreviated as 'mt'. The following changes were made:
7344 dump-me -> maintenance dump-me
7345 info all-breakpoints -> maintenance info breakpoints
7346 printmsyms -> maintenance print msyms
7347 printobjfiles -> maintenance print objfiles
7348 printpsyms -> maintenance print psymbols
7349 printsyms -> maintenance print symbols
7351 The following commands are new:
7353 maintenance demangle Call internal GDB demangler routine to
7354 demangle a C++ link name and prints the result.
7355 maintenance print type Print a type chain for a given symbol
7357 * Change to .gdbinit file processing
7359 We now read the $HOME/.gdbinit file before processing the argv arguments
7360 (e.g. reading symbol files or core files). This allows global parameters to
7361 be set, which will apply during the symbol reading. The ./.gdbinit is still
7362 read after argv processing.
7364 * New hosts supported
7366 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
7368 GNU/Linux support i386-unknown-linux or linux
7370 We are also including code to support the HP/PA running BSD and HPUX. This
7371 is almost guaranteed not to work, as we didn't have time to test or build it
7372 for this release. We are including it so that the more adventurous (or
7373 masochistic) of you can play with it. We also had major problems with the
7374 fact that the compiler that we got from HP doesn't support the -g option.
7377 * New targets supported
7379 Hitachi H8/300 h8300-hitachi-hms or h8300hms
7381 * More smarts about finding #include files
7383 GDB now remembers the compilation directory for all include files, and for
7384 all files from which C is generated (like yacc and lex sources). This
7385 greatly improves GDB's ability to find yacc/lex sources, and include files,
7386 especially if you are debugging your program from a directory different from
7387 the one that contains your sources.
7389 We also fixed a bug which caused difficulty with listing and setting
7390 breakpoints in include files which contain C code. (In the past, you had to
7391 try twice in order to list an include file that you hadn't looked at before.)
7393 * Interesting infernals change
7395 GDB now deals with arbitrary numbers of sections, where the symbols for each
7396 section must be relocated relative to that section's landing place in the
7397 target's address space. This work was needed to support ELF with embedded
7398 stabs used by Solaris-2.0.
7400 * Bug fixes (of course!)
7402 There have been loads of fixes for the following things:
7403 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
7404 i960, stabs, DOS(GO32), procfs, etc...
7406 See the ChangeLog for details.
7408 *** Changes in GDB-4.5:
7410 * New machines supported (host and target)
7412 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
7414 SGI Irix-4.x mips-sgi-irix4 or iris4
7416 * New malloc package
7418 GDB now uses a new memory manager called mmalloc, based on gmalloc.
7419 Mmalloc is capable of handling multiple heaps of memory. It is also
7420 capable of saving a heap to a file, and then mapping it back in later.
7421 This can be used to greatly speedup the startup of GDB by using a
7422 pre-parsed symbol table which lives in a mmalloc managed heap. For
7423 more details, please read mmalloc/mmalloc.texi.
7427 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
7428 'help info proc' for details.
7430 * MIPS ecoff symbol table format
7432 The code that reads MIPS symbol table format is now supported on all hosts.
7433 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
7436 * File name changes for MS-DOS
7438 Many files in the config directories have been renamed to make it easier to
7439 support GDB on MS-DOSe systems (which have very restrictive file name
7440 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
7441 environment) is close to working but has some remaining problems. Note
7442 that debugging of DOS programs is not supported, due to limitations
7443 in the ``operating system'', but it can be used to host cross-debugging.
7445 * Cross byte order fixes
7447 Many fixes have been made to support cross debugging of Sparc and MIPS
7448 targets from hosts whose byte order differs.
7450 * New -mapped and -readnow options
7452 If memory-mapped files are available on your system through the 'mmap'
7453 system call, you can use the -mapped option on the `file' or
7454 `symbol-file' commands to cause GDB to write the symbols from your
7455 program into a reusable file. If the program you are debugging is
7456 called `/path/fred', the mapped symbol file will be `./fred.syms'.
7457 Future GDB debugging sessions will notice the presence of this file,
7458 and will quickly map in symbol information from it, rather than reading
7459 the symbol table from the executable program. Using the '-mapped'
7460 option in a GDB `file' or `symbol-file' command has the same effect as
7461 starting GDB with the '-mapped' command-line option.
7463 You can cause GDB to read the entire symbol table immediately by using
7464 the '-readnow' option with any of the commands that load symbol table
7465 information (or on the GDB command line). This makes the command
7466 slower, but makes future operations faster.
7468 The -mapped and -readnow options are typically combined in order to
7469 build a `fred.syms' file that contains complete symbol information.
7470 A simple GDB invocation to do nothing but build a `.syms' file for future
7473 gdb -batch -nx -mapped -readnow programname
7475 The `.syms' file is specific to the host machine on which GDB is run.
7476 It holds an exact image of GDB's internal symbol table. It cannot be
7477 shared across multiple host platforms.
7479 * longjmp() handling
7481 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
7482 siglongjmp() without losing control. This feature has not yet been ported to
7483 all systems. It currently works on many 386 platforms, all MIPS-based
7484 platforms (SGI, DECstation, etc), and Sun3/4.
7488 Preliminary work has been put in to support the new Solaris OS from Sun. At
7489 this time, it can control and debug processes, but it is not capable of
7494 As always, many many bug fixes. The major areas were with g++, and mipsread.
7495 People using the MIPS-based platforms should experience fewer mysterious
7496 crashes and trashed symbol tables.
7498 *** Changes in GDB-4.4:
7500 * New machines supported (host and target)
7502 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7504 BSD Reno on Vax vax-dec-bsd
7505 Ultrix on Vax vax-dec-ultrix
7507 * New machines supported (target)
7509 AMD 29000 embedded, using EBMON a29k-none-none
7513 GDB continues to improve its handling of C++. `References' work better.
7514 The demangler has also been improved, and now deals with symbols mangled as
7515 per the Annotated C++ Reference Guide.
7517 GDB also now handles `stabs' symbol information embedded in MIPS
7518 `ecoff' symbol tables. Since the ecoff format was not easily
7519 extensible to handle new languages such as C++, this appeared to be a
7520 good way to put C++ debugging info into MIPS binaries. This option
7521 will be supported in the GNU C compiler, version 2, when it is
7524 * New features for SVR4
7526 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7527 shared libraries. Debugging dynamically linked programs should present
7528 only minor differences from debugging statically linked programs.
7530 The `info proc' command will print out information about any process
7531 on an SVR4 system (including the one you are debugging). At the moment,
7532 it prints the address mappings of the process.
7534 If you bring up GDB on another SVR4 system, please send mail to
7535 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7537 * Better dynamic linking support in SunOS
7539 Reading symbols from shared libraries which contain debugging symbols
7540 now works properly. However, there remain issues such as automatic
7541 skipping of `transfer vector' code during function calls, which
7542 make it harder to debug code in a shared library, than to debug the
7543 same code linked statically.
7547 GDB is now using the latest `getopt' routines from the FSF. This
7548 version accepts the -- prefix for options with long names. GDB will
7549 continue to accept the old forms (-option and +option) as well.
7550 Various single letter abbreviations for options have been explicity
7551 added to the option table so that they won't get overshadowed in the
7552 future by other options that begin with the same letter.
7556 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7557 Many assorted bugs have been handled. Many more remain to be handled.
7558 See the various ChangeLog files (primarily in gdb and bfd) for details.
7561 *** Changes in GDB-4.3:
7563 * New machines supported (host and target)
7565 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7566 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7567 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7569 * Almost SCO Unix support
7571 We had hoped to support:
7572 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7573 (except for core file support), but we discovered very late in the release
7574 that it has problems with process groups that render gdb unusable. Sorry
7575 about that. I encourage people to fix it and post the fixes.
7577 * Preliminary ELF and DWARF support
7579 GDB can read ELF object files on System V Release 4, and can handle
7580 debugging records for C, in DWARF format, in ELF files. This support
7581 is preliminary. If you bring up GDB on another SVR4 system, please
7582 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7587 GDB now uses the latest `readline' library. One user-visible change
7588 is that two tabs will list possible command completions, which previously
7589 required typing M-? (meta-question mark, or ESC ?).
7593 The `stepi' bug that many of you noticed has been squashed.
7594 Many bugs in C++ have been handled. Many more remain to be handled.
7595 See the various ChangeLog files (primarily in gdb and bfd) for details.
7597 * State of the MIPS world (in case you wondered):
7599 GDB can understand the symbol tables emitted by the compilers
7600 supplied by most vendors of MIPS-based machines, including DEC. These
7601 symbol tables are in a format that essentially nobody else uses.
7603 Some versions of gcc come with an assembler post-processor called
7604 mips-tfile. This program is required if you want to do source-level
7605 debugging of gcc-compiled programs. I believe FSF does not ship
7606 mips-tfile with gcc version 1, but it will eventually come with gcc
7609 Debugging of g++ output remains a problem. g++ version 1.xx does not
7610 really support it at all. (If you're lucky, you should be able to get
7611 line numbers and stack traces to work, but no parameters or local
7612 variables.) With some work it should be possible to improve the
7615 When gcc version 2 is released, you will have somewhat better luck.
7616 However, even then you will get confusing results for inheritance and
7619 We will eventually provide full debugging of g++ output on
7620 DECstations. This will probably involve some kind of stabs-in-ecoff
7621 encapulation, but the details have not been worked out yet.
7624 *** Changes in GDB-4.2:
7626 * Improved configuration
7628 Only one copy of `configure' exists now, and it is not self-modifying.
7629 Porting BFD is simpler.
7633 The `step' and `next' commands now only stop at the first instruction
7634 of a source line. This prevents the multiple stops that used to occur
7635 in switch statements, for-loops, etc. `Step' continues to stop if a
7636 function that has debugging information is called within the line.
7640 Lots of small bugs fixed. More remain.
7642 * New host supported (not target)
7644 Intel 386 PC clone running Mach i386-none-mach
7647 *** Changes in GDB-4.1:
7649 * Multiple source language support
7651 GDB now has internal scaffolding to handle several source languages.
7652 It determines the type of each source file from its filename extension,
7653 and will switch expression parsing and number formatting to match the
7654 language of the function in the currently selected stack frame.
7655 You can also specifically set the language to be used, with
7656 `set language c' or `set language modula-2'.
7660 GDB now has preliminary support for the GNU Modula-2 compiler,
7661 currently under development at the State University of New York at
7662 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7663 continue through the fall of 1991 and into 1992.
7665 Other Modula-2 compilers are currently not supported, and attempting to
7666 debug programs compiled with them will likely result in an error as the
7667 symbol table is read. Feel free to work on it, though!
7669 There are hooks in GDB for strict type checking and range checking,
7670 in the `Modula-2 philosophy', but they do not currently work.
7674 GDB can now write to executable and core files (e.g. patch
7675 a variable's value). You must turn this switch on, specify
7676 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7677 by assigning a new value to a variable. Modifications take
7680 * Automatic SunOS shared library reading
7682 When you run your program, GDB automatically determines where its
7683 shared libraries (if any) have been loaded, and reads their symbols.
7684 The `share' command is no longer needed. This also works when
7685 examining core files.
7689 You can specify the number of lines that the `list' command shows.
7692 * New machines supported (host and target)
7694 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7695 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7696 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7698 * New hosts supported (not targets)
7700 IBM RT/PC: romp-ibm-aix or rtpc
7702 * New targets supported (not hosts)
7704 AMD 29000 embedded with COFF a29k-none-coff
7705 AMD 29000 embedded with a.out a29k-none-aout
7706 Ultracomputer remote kernel debug a29k-nyu-kern
7708 * New remote interfaces
7714 *** Changes in GDB-4.0:
7718 Wide output is wrapped at good places to make the output more readable.
7720 Gdb now supports cross-debugging from a host machine of one type to a
7721 target machine of another type. Communication with the target system
7722 is over serial lines. The ``target'' command handles connecting to the
7723 remote system; the ``load'' command will download a program into the
7724 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7725 also supports debugging of realtime processes running under VxWorks,
7726 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7727 stub on the target system.
7729 New CPUs supported include the AMD 29000 and Intel 960.
7731 GDB now reads object files and symbol tables via a ``binary file''
7732 library, which allows a single copy of GDB to debug programs of multiple
7733 object file types such as a.out and coff.
7735 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7736 refcard.dvi and refcard.ps are available to format it).
7739 * Control-Variable user interface simplified
7741 All variables that control the operation of the debugger can be set
7742 by the ``set'' command, and displayed by the ``show'' command.
7744 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7745 ``Show prompt'' produces the response:
7746 Gdb's prompt is new-gdb=>.
7748 What follows are the NEW set commands. The command ``help set'' will
7749 print a complete list of old and new set commands. ``help set FOO''
7750 will give a longer description of the variable FOO. ``show'' will show
7751 all of the variable descriptions and their current settings.
7753 confirm on/off: Enables warning questions for operations that are
7754 hard to recover from, e.g. rerunning the program while
7755 it is already running. Default is ON.
7757 editing on/off: Enables EMACS style command line editing
7758 of input. Previous lines can be recalled with
7759 control-P, the current line can be edited with control-B,
7760 you can search for commands with control-R, etc.
7763 history filename NAME: NAME is where the gdb command history
7764 will be stored. The default is .gdb_history,
7765 or the value of the environment variable
7768 history size N: The size, in commands, of the command history. The
7769 default is 256, or the value of the environment variable
7772 history save on/off: If this value is set to ON, the history file will
7773 be saved after exiting gdb. If set to OFF, the
7774 file will not be saved. The default is OFF.
7776 history expansion on/off: If this value is set to ON, then csh-like
7777 history expansion will be performed on
7778 command line input. The default is OFF.
7780 radix N: Sets the default radix for input and output. It can be set
7781 to 8, 10, or 16. Note that the argument to "radix" is interpreted
7782 in the current radix, so "set radix 10" is always a no-op.
7784 height N: This integer value is the number of lines on a page. Default
7785 is 24, the current `stty rows'' setting, or the ``li#''
7786 setting from the termcap entry matching the environment
7789 width N: This integer value is the number of characters on a line.
7790 Default is 80, the current `stty cols'' setting, or the ``co#''
7791 setting from the termcap entry matching the environment
7794 Note: ``set screensize'' is obsolete. Use ``set height'' and
7795 ``set width'' instead.
7797 print address on/off: Print memory addresses in various command displays,
7798 such as stack traces and structure values. Gdb looks
7799 more ``symbolic'' if you turn this off; it looks more
7800 ``machine level'' with it on. Default is ON.
7802 print array on/off: Prettyprint arrays. New convenient format! Default
7805 print demangle on/off: Print C++ symbols in "source" form if on,
7808 print asm-demangle on/off: Same, for assembler level printouts
7811 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7814 * Support for Epoch Environment.
7816 The epoch environment is a version of Emacs v18 with windowing. One
7817 new command, ``inspect'', is identical to ``print'', except that if you
7818 are running in the epoch environment, the value is printed in its own
7822 * Support for Shared Libraries
7824 GDB can now debug programs and core files that use SunOS shared libraries.
7825 Symbols from a shared library cannot be referenced
7826 before the shared library has been linked with the program (this
7827 happens after you type ``run'' and before the function main() is entered).
7828 At any time after this linking (including when examining core files
7829 from dynamically linked programs), gdb reads the symbols from each
7830 shared library when you type the ``sharedlibrary'' command.
7831 It can be abbreviated ``share''.
7833 sharedlibrary REGEXP: Load shared object library symbols for files
7834 matching a unix regular expression. No argument
7835 indicates to load symbols for all shared libraries.
7837 info sharedlibrary: Status of loaded shared libraries.
7842 A watchpoint stops execution of a program whenever the value of an
7843 expression changes. Checking for this slows down execution
7844 tremendously whenever you are in the scope of the expression, but is
7845 quite useful for catching tough ``bit-spreader'' or pointer misuse
7846 problems. Some machines such as the 386 have hardware for doing this
7847 more quickly, and future versions of gdb will use this hardware.
7849 watch EXP: Set a watchpoint (breakpoint) for an expression.
7851 info watchpoints: Information about your watchpoints.
7853 delete N: Deletes watchpoint number N (same as breakpoints).
7854 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7855 enable N: Re-enables watchpoint number N (same as breakpoints).
7858 * C++ multiple inheritance
7860 When used with a GCC version 2 compiler, GDB supports multiple inheritance
7863 * C++ exception handling
7865 Gdb now supports limited C++ exception handling. Besides the existing
7866 ability to breakpoint on an exception handler, gdb can breakpoint on
7867 the raising of an exception (before the stack is peeled back to the
7870 catch FOO: If there is a FOO exception handler in the dynamic scope,
7871 set a breakpoint to catch exceptions which may be raised there.
7872 Multiple exceptions (``catch foo bar baz'') may be caught.
7874 info catch: Lists all exceptions which may be caught in the
7875 current stack frame.
7878 * Minor command changes
7880 The command ``call func (arg, arg, ...)'' now acts like the print
7881 command, except it does not print or save a value if the function's result
7882 is void. This is similar to dbx usage.
7884 The ``up'' and ``down'' commands now always print the frame they end up
7885 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7886 frames without printing.
7888 * New directory command
7890 'dir' now adds directories to the FRONT of the source search path.
7891 The path starts off empty. Source files that contain debug information
7892 about the directory in which they were compiled can be found even
7893 with an empty path; Sun CC and GCC include this information. If GDB can't
7894 find your source file in the current directory, type "dir .".
7896 * Configuring GDB for compilation
7898 For normal use, type ``./configure host''. See README or gdb.texinfo
7901 GDB now handles cross debugging. If you are remotely debugging between
7902 two different machines, type ``./configure host -target=targ''.
7903 Host is the machine where GDB will run; targ is the machine
7904 where the program that you are debugging will run.