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
84 alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
85 The alias command can now specify default args for an alias.
86 GDB automatically prepends the alias default args to the argument list
87 provided explicitly by the user.
88 For example, to have a backtrace with full details, you can define
90 'alias bt_ALL = backtrace -entry-values both -frame-arg all
91 -past-main -past-entry -full'.
92 Alias default arguments can also use a set of nested 'with' commands,
93 e.g. 'alias pp10 = with print pretty -- with print elem 10 -- print'
94 defines the alias pp10 that will pretty print a maximum of 10 elements
95 of the given expression (if the expression is an array).
99 GNU/Linux/RISC-V (gdbserver) riscv*-*-linux*
103 ** gdb.register_window_type can be used to implement new TUI windows
106 ** Dynamic types can now be queried. gdb.Type has a new attribute,
107 "dynamic", and gdb.Type.sizeof can be None for a dynamic type. A
108 field of a dynamic type may have None for its "bitpos" attribute
111 ** Commands written in Python can be in the "TUI" help class by
112 registering with the new constant gdb.COMMAND_TUI.
116 * 'thread-exited' event is now available in the annotations interface.
118 * New built-in convenience variables $_gdb_major and $_gdb_minor
119 provide the GDB version. They are handy for conditionally using
120 features available only in or since specific GDB versions, in
121 scripts that should work error-free with many different versions,
122 such as in system-wide init files.
124 * New built-in convenience functions $_gdb_setting, $_gdb_setting_str,
125 $_gdb_maint_setting and $_gdb_maint_setting_str provide access to values
126 of the GDB settings and the GDB maintenance settings. They are handy
127 for changing the logic of user defined commands depending on the
128 current GDB settings.
130 * GDB now supports Thread Local Storage (TLS) variables on several
131 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
132 architectures require kernel changes. TLS is not yet supported for
133 amd64 and i386 process core dumps.
135 * Support for Pointer Authentication (PAC) on AArch64 Linux. Return
136 addresses that required unmasking are shown in the backtrace with the
139 * Two new convenience functions $_cimag and $_creal that extract the
140 imaginary and real parts respectively from complex numbers.
142 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
143 provide the exitcode or exit status of the shell commands launched by
144 GDB commands such as "shell", "pipe" and "make".
146 * The command define-prefix can now define user defined prefix commands.
147 User defined commands can now be defined using these user defined prefix
150 * Command names can now use the . character.
152 * The RX port now supports XML target descriptions.
154 * GDB now shows the Ada task names at more places, e.g. in task switching
157 * GDB can now be compiled with Python 3 on Windows.
159 * New convenience variable $_ada_exception holds the address of the
160 Ada exception being thrown. This is set by Ada-related catchpoints.
162 * GDB can now place breakpoints on nested functions and subroutines in
163 Fortran code. The '::' operator can be used between parent and
164 child scopes when placing breakpoints, for example:
166 (gdb) break outer_function::inner_function
168 The 'outer_function::' prefix is only needed if 'inner_function' is
169 not visible in the current scope.
171 * In addition to the system-wide gdbinit file, if configured with
172 --with-system-gdbinit-dir, GDB will now also load files in that directory
173 as system gdbinit files, unless the -nx or -n flag is provided. Files
174 with extensions .gdb, .py and .scm are supported as long as GDB was
175 compiled with support for that language.
177 * GDB now supports multithreaded symbol loading for higher performance.
178 This feature is still in testing, so it is disabled by default. You
179 can turn it on using 'maint set worker-threads unlimited'.
181 * Multi-target debugging support
183 GDB now supports debugging multiple target connections
184 simultaneously. For example, you can now have each inferior
185 connected to different remote servers running in different machines,
186 or have one inferior debugging a local native process, an inferior
187 debugging a core dump, etc.
189 This support is experimental and comes with some limitations -- you
190 can only resume multiple targets simultaneously if all targets
191 support non-stop mode, and all remote stubs or servers must support
192 the same set of remote protocol features exactly. See also "info
193 connections" and "add-inferior -no-connection" below, and "maint set
194 target-non-stop" in the user manual.
198 ** The gdb.Value type has a new method 'format_string' which returns a
199 string representing the value. The formatting is controlled by the
200 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
201 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
202 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
204 ** gdb.Type has a new property 'objfile' which returns the objfile the
207 ** The frame information printed by the python frame filtering code
208 is now consistent with what the 'backtrace' command prints when
209 there are no filters, or when the 'backtrace' '-no-filters' option
212 ** The new function gdb.lookup_static_symbol can be used to look up
213 symbols with static linkage.
215 ** The new function gdb.lookup_static_symbols can be used to look up
216 all static symbols with static linkage.
218 ** gdb.Objfile has new methods 'lookup_global_symbol' and
219 'lookup_static_symbol' to lookup a symbol from this objfile only.
221 ** gdb.Block now supports the dictionary syntax for accessing symbols in
222 this block (e.g. block['local_variable']).
226 | [COMMAND] | SHELL_COMMAND
227 | -d DELIM COMMAND DELIM SHELL_COMMAND
228 pipe [COMMAND] | SHELL_COMMAND
229 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
230 Executes COMMAND and sends its output to SHELL_COMMAND.
231 With no COMMAND, repeat the last executed command
232 and send its output to SHELL_COMMAND.
234 define-prefix COMMAND
235 Define or mark a command as a user-defined prefix command.
237 with SETTING [VALUE] [-- COMMAND]
238 w SETTING [VALUE] [-- COMMAND]
239 Temporarily set SETTING, run COMMAND, and restore SETTING.
240 Usage: with SETTING -- COMMAND
241 With no COMMAND, repeats the last executed command.
242 SETTING is any GDB setting you can change with the "set"
243 subcommands. For example, 'with language c -- print someobj'
244 temporarily switches to the C language in order to print someobj.
245 Settings can be combined: 'w lang c -- w print elements unlimited --
246 usercmd' switches to the C language and runs usercmd with no limit
247 of array elements to print.
249 maint with SETTING [VALUE] [-- COMMAND]
250 Like "with", but works with "maintenance set" settings.
252 set may-call-functions [on|off]
253 show may-call-functions
254 This controls whether GDB will attempt to call functions in
255 the program, such as with expressions in the print command. It
256 defaults to on. Calling functions in the program being debugged
257 can have undesired side effects. It is now possible to forbid
258 such function calls. If function calls are forbidden, GDB will throw
259 an error when a command (such as print expression) calls a function
262 set print finish [on|off]
264 This controls whether the `finish' command will display the value
265 that is returned by the current function. When `off', the value is
266 still entered into the value history, but it is not printed. The
271 Allows deeply nested structures to be simplified when printing by
272 replacing deeply nested parts (beyond the max-depth) with ellipses.
273 The default max-depth is 20, but this can be set to unlimited to get
274 the old behavior back.
276 set print raw-values [on|off]
277 show print raw-values
278 By default, GDB applies the enabled pretty printers when printing a
279 value. This allows to ignore the enabled pretty printers for a series
280 of commands. The default is 'off'.
282 set logging debugredirect [on|off]
283 By default, GDB debug output will go to both the terminal and the logfile.
284 Set if you want debug output to go only to the log file.
286 set style title foreground COLOR
287 set style title background COLOR
288 set style title intensity VALUE
289 Control the styling of titles.
291 set style highlight foreground COLOR
292 set style highlight background COLOR
293 set style highlight intensity VALUE
294 Control the styling of highlightings.
296 maint set worker-threads
297 maint show worker-threads
298 Control the number of worker threads that can be used by GDB. The
299 default is 0. "unlimited" lets GDB choose a number that is
300 reasonable. Currently worker threads are only used when demangling
301 the names of linker symbols.
303 set style tui-border foreground COLOR
304 set style tui-border background COLOR
305 Control the styling of TUI borders.
307 set style tui-active-border foreground COLOR
308 set style tui-active-border background COLOR
309 Control the styling of the active TUI border.
311 maint set test-settings KIND
312 maint show test-settings KIND
313 A set of commands used by the testsuite for exercising the settings
316 maint set tui-resize-message [on|off]
317 maint show tui-resize-message
318 Control whether GDB prints a message each time the terminal is
319 resized when in TUI mode. This is primarily useful for testing the
322 set print frame-info [short-location|location|location-and-address
323 |source-and-location|source-line|auto]
324 show print frame-info
325 This controls what frame information is printed by the commands printing
326 a frame. This setting will e.g. influence the behaviour of 'backtrace',
327 'frame', 'stepi'. The python frame filtering also respect this setting.
328 The 'backtrace' '-frame-info' option can override this global setting.
330 set tui compact-source
331 show tui compact-source
333 Enable the "compact" display mode for the TUI source window. The
334 compact display uses only as much space as is needed for the line
335 numbers in the current file, and only a single space to separate the
336 line numbers from the source.
338 info modules [-q] [REGEXP]
339 Return a list of Fortran modules matching REGEXP, or all modules if
342 info module functions [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
343 Return a list of functions within all modules, grouped by module.
344 The list of functions can be restricted with the optional regular
345 expressions. MODULE_REGEXP matches against the module name,
346 TYPE_REGEXP matches against the function type signature, and REGEXP
347 matches against the function name.
349 info module variables [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
350 Return a list of variables within all modules, grouped by module.
351 The list of variables can be restricted with the optional regular
352 expressions. MODULE_REGEXP matches against the module name,
353 TYPE_REGEXP matches against the variable type, and REGEXP matches
354 against the variable name.
356 set debug remote-packet-max-chars
357 show debug remote-packet-max-chars
358 Controls the number of characters to output in a remote packet when using
360 The default is 512 bytes.
363 Lists the target connections currently in use.
368 The "help" command uses the title style to enhance the
369 readibility of its output by styling the classes and
373 Similarly to "help", the "apropos" command also uses the
374 title style for the command names. "apropos" accepts now
375 a flag "-v" (verbose) to show the full documentation
376 of matching commands and to use the highlight style to mark
377 the documentation parts matching REGEXP.
381 The GDB printf and eval commands can now print C-style and Ada-style
382 string convenience variables without calling functions in the program.
383 This allows to do formatted printing of strings without having
384 a running inferior, or when debugging a core dump.
386 info sources [-dirname | -basename] [--] [REGEXP]
387 This command has now optional arguments to only print the files
388 whose names match REGEXP. The arguments -dirname and -basename
389 allow to restrict matching respectively to the dirname and basename
393 The "show style" and its subcommands are now styling
394 a style name in their output using its own style, to help
395 the user visualize the different styles.
397 set print frame-arguments
398 The new value 'presence' indicates to only indicate the presence of
399 arguments using ..., instead of printing argument names and values.
401 set print raw-frame-arguments
402 show print raw-frame-arguments
404 These commands replace the similarly-named "set/show print raw
405 frame-arguments" commands (now with a dash instead of a space). The
406 old commands are now deprecated and may be removed in a future
409 add-inferior [-no-connection]
410 The add-inferior command now supports a "-no-connection" flag that
411 makes the new inferior start with no target connection associated.
412 By default, the new inferior inherits the target connection of the
413 current inferior. See also "info connections".
416 This command's output now includes a new "Connection" column
417 indicating which target connection an inferior is bound to. See
418 "info connections" above.
420 maint test-options require-delimiter
421 maint test-options unknown-is-error
422 maint test-options unknown-is-operand
423 maint show test-options-completion-result
424 Commands used by the testsuite to validate the command options
427 focus, winheight, +, -, >, <
428 These commands are now case-sensitive.
430 * New command options, command completion
432 GDB now has a standard infrastructure to support dash-style command
433 options ('-OPT'). One benefit is that commands that use it can
434 easily support completion of command line arguments. Try "CMD
435 -[TAB]" or "help CMD" to find options supported by a command. Over
436 time, we intend to migrate most commands to this infrastructure. A
437 number of commands got support for new command options in this
440 ** The "print" and "compile print" commands now support a number of
441 options that allow overriding relevant global print settings as
442 set by "set print" subcommands:
446 -array-indexes [on|off]
447 -elements NUMBER|unlimited
452 -repeats NUMBER|unlimited
453 -static-members [on|off]
458 Note that because the "print"/"compile print" commands accept
459 arbitrary expressions which may look like options (including
460 abbreviations), if you specify any command option, then you must
461 use a double dash ("--") to mark the end of argument processing.
463 ** The "backtrace" command now supports a number of options that
464 allow overriding relevant global print settings as set by "set
465 backtrace" and "set print" subcommands:
467 -entry-values no|only|preferred|if-needed|both|compact|default
468 -frame-arguments all|scalars|none
469 -raw-frame-arguments [on|off]
470 -frame-info auto|source-line|location|source-and-location
471 |location-and-address|short-location
475 In addition, the full/no-filters/hide qualifiers are now also
476 exposed as command options too:
482 ** The "frame apply", "tfaas" and "faas" commands similarly now
483 support the following options:
488 ** The new "info sources" options -dirname and -basename options
489 are using the standard '-OPT' infrastructure.
491 All options above can also be abbreviated. The argument of boolean
492 (on/off) options can be 0/1 too, and also the argument is assumed
493 "on" if omitted. This allows writing compact command invocations,
496 (gdb) p -ra -p -o 0 -- *myptr
498 The above is equivalent to:
500 (gdb) print -raw-values -pretty -object off -- *myptr
502 ** The "info types" command now supports the '-q' flag to disable
503 printing of some header information in a similar fashion to "info
504 variables" and "info functions".
506 ** The "info variables", "info functions", and "whereis" commands
507 now take a '-n' flag that excludes non-debug symbols (symbols
508 from the symbol table, not from the debug info such as DWARF)
511 * Completion improvements
513 ** GDB can now complete the options of the "thread apply all" and
514 "taas" commands, and their "-ascending" option can now be
517 ** GDB can now complete the options of the "info threads", "info
518 functions", "info variables", "info locals", and "info args"
521 ** GDB can now complete the options of the "compile file" and
522 "compile code" commands. The "compile file" command now
523 completes on filenames.
525 ** GDB can now complete the backtrace command's
526 "full/no-filters/hide" qualifiers.
528 * In settings, you can now abbreviate "unlimited".
530 E.g., "set print elements u" is now equivalent to "set print
536 This lists all the possible completions for the rest of the line, if it
537 were to be given as a command itself. This is intended for use by MI
538 frontends in cases when separate CLI and MI channels cannot be used.
540 -catch-throw, -catch-rethrow, and -catch-catch
541 These can be used to catch C++ exceptions in a similar fashion to
542 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
544 -symbol-info-functions, -symbol-info-types, and -symbol-info-variables
545 These commands are the MI equivalent of the CLI commands 'info
546 functions', 'info types', and 'info variables' respectively.
548 -symbol-info-modules, this is the MI equivalent of the CLI 'info
551 -symbol-info-module-functions and -symbol-info-module-variables.
552 These commands are the MI equivalent of the CLI commands 'info
553 module functions' and 'info module variables'.
557 ** The default version of the MI interpreter is now 3 (-i=mi3).
559 ** The output of information about multi-location breakpoints (which is
560 syntactically incorrect in MI 2) has changed in MI 3. This affects
561 the following commands and events:
565 - =breakpoint-created
566 - =breakpoint-modified
568 The -fix-multi-location-breakpoint-output command can be used to enable
569 this behavior with previous MI versions.
571 ** Backtraces and frames include a new optional field addr_flags which is
572 given after the addr field. On AArch64 this contains PAC if the address
573 has been masked in the frame. On all other targets the field is not
578 The testsuite now creates the files gdb.cmd (containing the arguments
579 used to launch GDB) and gdb.in (containing all the commands sent to
580 GDB) in the output directory for each test script. Multiple invocations
581 are appended with .1, .2, .3 etc.
583 * Building GDB and GDBserver now requires GNU make >= 3.82.
585 Using another implementation of the make program or an earlier version of
586 GNU make to build GDB or GDBserver is not supported.
588 * Building GDB now requires GNU readline >= 7.0.
590 GDB now bundles GNU readline 8.0, but if you choose to use
591 --with-system-readline, only readline >= 7.0 can be used.
593 * The TUI SingleKey keymap is now named "SingleKey". This can be used
594 from .inputrc to bind keys in this keymap. This feature is only
595 available when gdb is built against GNU readline 8.0 or later.
597 * Removed targets and native configurations
599 GDB no longer supports debugging the Cell Broadband Engine. This includes
600 both debugging standalone Cell/B.E. SPU applications and integrated debugging
601 of Cell/B.E. applications that use both the PPU and SPU architectures.
607 * Removed targets and native configurations
609 Solaris 10 i?86-*-solaris2.10, x86_64-*-solaris2.10,
612 *** Changes in GDB 8.3
614 * GDB and GDBserver now support access to additional registers on
615 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
618 * GDB now has experimental support for the compilation and injection of
619 C++ source code into the inferior. This beta release does not include
620 support for several language features, such as templates, constructors,
623 This feature requires GCC 7.1 or higher built with libcp1.so
626 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
627 can be passed using the '[ADDRESS]:PORT' notation, or the regular
628 'ADDRESS:PORT' method.
630 * DWARF index cache: GDB can now automatically save indices of DWARF
631 symbols on disk to speed up further loading of the same binaries.
633 * Ada task switching is now supported on aarch64-elf targets when
634 debugging a program using the Ravenscar Profile. For more information,
635 see the "Tasking Support when using the Ravenscar Profile" section
636 in the GDB user manual.
638 * GDB in batch mode now exits with status 1 if the last command to be
641 * The RISC-V target now supports target descriptions.
643 * System call catchpoints now support system call aliases on FreeBSD.
644 When the ABI of a system call changes in FreeBSD, this is
645 implemented by leaving a compatibility system call using the old ABI
646 at the existing number and allocating a new system call number for
647 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
648 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
649 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
650 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
651 so that a system call catchpoint for the 'kevent' system call will
652 catch invocations of both the 'kevent' and 'freebsd11_kevent'
653 binaries. This ensures that 'kevent' system calls are caught for
654 binaries using either the old or new ABIs.
656 * Terminal styling is now available for the CLI and the TUI. GNU
657 Source Highlight can additionally be used to provide styling of
658 source code snippets. See the "set style" commands, below, for more
661 * Removed support for old demangling styles arm, edg, gnu, hp and
666 set debug compile-cplus-types
667 show debug compile-cplus-types
668 Control the display of debug output about type conversion in the
669 C++ compile feature. Commands have no effect while compiling
674 Control whether debug output about files/functions skipping is
677 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
678 Apply a command to some frames.
679 FLAG arguments allow to control what output to produce and how to handle
680 errors raised when applying COMMAND to a frame.
683 Apply a command to all threads (ignoring errors and empty output).
684 Shortcut for 'thread apply all -s COMMAND'.
687 Apply a command to all frames (ignoring errors and empty output).
688 Shortcut for 'frame apply all -s COMMAND'.
691 Apply a command to all frames of all threads (ignoring errors and empty
693 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
695 maint set dwarf unwinders (on|off)
696 maint show dwarf unwinders
697 Control whether DWARF unwinders can be used.
700 Display a list of open files for a process.
704 Changes to the "frame", "select-frame", and "info frame" CLI commands.
705 These commands all now take a frame specification which
706 is either a frame level, or one of the keywords 'level', 'address',
707 'function', or 'view' followed by a parameter. Selecting a frame by
708 address, or viewing a frame outside the current backtrace now
709 requires the use of a keyword. Selecting a frame by level is
710 unchanged. The MI comment "-stack-select-frame" is unchanged.
712 target remote FILENAME
713 target extended-remote FILENAME
714 If FILENAME is a Unix domain socket, GDB will attempt to connect
715 to this socket instead of opening FILENAME as a character device.
717 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
718 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
719 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
720 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
721 These commands can now print only the searched entities
722 matching the provided regexp(s), giving a condition
723 on the entity names or entity types. The flag -q disables
724 printing headers or informations messages.
730 These commands now determine the syntax for the shown entities
731 according to the language chosen by `set language'. In particular,
732 `set language auto' means to automatically choose the language of
735 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
736 The 'thread apply' command accepts new FLAG arguments.
737 FLAG arguments allow to control what output to produce and how to handle
738 errors raised when applying COMMAND to a thread.
740 set tui tab-width NCHARS
741 show tui tab-width NCHARS
742 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
744 set style enabled [on|off]
746 Enable or disable terminal styling. Styling is enabled by default
747 on most hosts, but disabled by default when in batch mode.
749 set style sources [on|off]
751 Enable or disable source code styling. Source code styling is
752 enabled by default, but only takes effect if styling in general is
753 enabled, and if GDB was linked with GNU Source Highlight.
755 set style filename foreground COLOR
756 set style filename background COLOR
757 set style filename intensity VALUE
758 Control the styling of file names.
760 set style function foreground COLOR
761 set style function background COLOR
762 set style function intensity VALUE
763 Control the styling of function names.
765 set style variable foreground COLOR
766 set style variable background COLOR
767 set style variable intensity VALUE
768 Control the styling of variable names.
770 set style address foreground COLOR
771 set style address background COLOR
772 set style address intensity VALUE
773 Control the styling of addresses.
777 ** The '-data-disassemble' MI command now accepts an '-a' option to
778 disassemble the whole function surrounding the given program
779 counter value or function name. Support for this feature can be
780 verified by using the "-list-features" command, which should
781 contain "data-disassemble-a-option".
783 ** Command responses and notifications that include a frame now include
784 the frame's architecture in a new "arch" attribute.
786 * New native configurations
788 GNU/Linux/RISC-V riscv*-*-linux*
789 FreeBSD/riscv riscv*-*-freebsd*
793 GNU/Linux/RISC-V riscv*-*-linux*
795 CSKY GNU/LINUX csky*-*-linux
796 FreeBSD/riscv riscv*-*-freebsd*
798 GNU/Linux/OpenRISC or1k*-*-linux*
802 GDB no longer supports native debugging on versions of MS-Windows
807 ** GDB no longer supports Python versions less than 2.6.
809 ** The gdb.Inferior type has a new 'progspace' property, which is the program
810 space associated to that inferior.
812 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
813 of objfiles associated to that program space.
815 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
816 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
819 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
820 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
821 correct and did not work properly.
823 ** The gdb.Value type has a new constructor, which is used to construct a
824 gdb.Value from a Python buffer object and a gdb.Type.
830 Enable or disable the undefined behavior sanitizer. This is
831 disabled by default, but passing --enable-ubsan=yes or
832 --enable-ubsan=auto to configure will enable it. Enabling this can
833 cause a performance penalty. The undefined behavior sanitizer was
834 first introduced in GCC 4.9.
836 *** Changes in GDB 8.2
838 * The 'set disassembler-options' command now supports specifying options
841 * The 'symbol-file' command now accepts an '-o' option to add a relative
842 offset to all sections.
844 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
845 a relative offset to all sections, but it allows to override the load
846 address of individual sections using '-s'.
848 * The 'add-symbol-file' command no longer requires the second argument
849 (address of the text section).
851 * The endianness used with the 'set endian auto' mode in the absence of
852 an executable selected for debugging is now the last endianness chosen
853 either by one of the 'set endian big' and 'set endian little' commands
854 or by inferring from the last executable used, rather than the startup
857 * The pager now allows a "c" response, meaning to disable the pager
858 for the rest of the current command.
860 * The commands 'info variables/functions/types' now show the source line
861 numbers of symbol definitions when available.
863 * 'info proc' now works on running processes on FreeBSD systems and core
864 files created on FreeBSD systems.
866 * C expressions can now use _Alignof, and C++ expressions can now use
869 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
870 the vector length while the process is running.
876 Control display of debugging info regarding the FreeBSD native target.
878 set|show varsize-limit
879 This new setting allows the user to control the maximum size of Ada
880 objects being printed when those objects have a variable type,
881 instead of that maximum size being hardcoded to 65536 bytes.
883 set|show record btrace cpu
884 Controls the processor to be used for enabling errata workarounds for
887 maint check libthread-db
888 Run integrity checks on the current inferior's thread debugging
891 maint set check-libthread-db (on|off)
892 maint show check-libthread-db
893 Control whether to run integrity checks on inferior specific thread
894 debugging libraries as they are loaded. The default is not to
899 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
901 ** The commands attached to a breakpoint can be set by assigning to
902 the breakpoint's "commands" field.
904 ** gdb.execute can now execute multi-line gdb commands.
906 ** The new functions gdb.convenience_variable and
907 gdb.set_convenience_variable can be used to get and set the value
908 of convenience variables.
910 ** A gdb.Parameter will no longer print the "set" help text on an
911 ordinary "set"; instead by default a "set" will be silent unless
912 the get_set_string method returns a non-empty string.
916 RiscV ELF riscv*-*-elf
918 * Removed targets and native configurations
920 m88k running OpenBSD m88*-*-openbsd*
921 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
922 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
923 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
925 * Aarch64/Linux hardware watchpoints improvements
927 Hardware watchpoints on unaligned addresses are now properly
928 supported when running Linux kernel 4.10 or higher: read and access
929 watchpoints are no longer spuriously missed, and all watchpoints
930 lengths between 1 and 8 bytes are supported. On older kernels,
931 watchpoints set on unaligned addresses are no longer missed, with
932 the tradeoff that there is a possibility of false hits being
937 --enable-codesign=CERT
938 This can be used to invoke "codesign -s CERT" after building gdb.
939 This option is useful on macOS, where code signing is required for
940 gdb to work properly.
942 --disable-gdbcli has been removed
943 This is now silently accepted, but does nothing.
945 *** Changes in GDB 8.1
947 * GDB now supports dynamically creating arbitrary register groups specified
948 in XML target descriptions. This allows for finer grain grouping of
949 registers on systems with a large amount of registers.
951 * The 'ptype' command now accepts a '/o' flag, which prints the
952 offsets and sizes of fields in a struct, like the pahole(1) tool.
954 * New "--readnever" command line option instructs GDB to not read each
955 symbol file's symbolic debug information. This makes startup faster
956 but at the expense of not being able to perform symbolic debugging.
957 This option is intended for use cases where symbolic debugging will
958 not be used, e.g., when you only need to dump the debuggee's core.
960 * GDB now uses the GNU MPFR library, if available, to emulate target
961 floating-point arithmetic during expression evaluation when the target
962 uses different floating-point formats than the host. At least version
963 3.1 of GNU MPFR is required.
965 * GDB now supports access to the guarded-storage-control registers and the
966 software-based guarded-storage broadcast control registers on IBM z14.
968 * On Unix systems, GDB now supports transmitting environment variables
969 that are to be set or unset to GDBserver. These variables will
970 affect the environment to be passed to the remote inferior.
972 To inform GDB of environment variables that are to be transmitted to
973 GDBserver, use the "set environment" command. Only user set
974 environment variables are sent to GDBserver.
976 To inform GDB of environment variables that are to be unset before
977 the remote inferior is started by the GDBserver, use the "unset
978 environment" command.
980 * Completion improvements
982 ** GDB can now complete function parameters in linespecs and
983 explicit locations without quoting. When setting breakpoints,
984 quoting around functions names to help with TAB-completion is
985 generally no longer necessary. For example, this now completes
988 (gdb) b function(in[TAB]
989 (gdb) b function(int)
991 Related, GDB is no longer confused with completing functions in
992 C++ anonymous namespaces:
995 (gdb) b (anonymous namespace)::[TAB][TAB]
996 (anonymous namespace)::a_function()
997 (anonymous namespace)::b_function()
999 ** GDB now has much improved linespec and explicit locations TAB
1000 completion support, that better understands what you're
1001 completing and offers better suggestions. For example, GDB no
1002 longer offers data symbols as possible completions when you're
1003 setting a breakpoint.
1005 ** GDB now TAB-completes label symbol names.
1007 ** The "complete" command now mimics TAB completion accurately.
1009 * New command line options (gcore)
1012 Dump all memory mappings.
1014 * Breakpoints on C++ functions are now set on all scopes by default
1016 By default, breakpoints on functions/methods are now interpreted as
1017 specifying all functions with the given name ignoring missing
1018 leading scopes (namespaces and classes).
1020 For example, assuming a C++ program with symbols named:
1025 both commands "break func()" and "break B::func()" set a breakpoint
1028 You can use the new flag "-qualified" to override this. This makes
1029 GDB interpret the specified function name as a complete
1030 fully-qualified name instead. For example, using the same C++
1031 program, the "break -q B::func" command sets a breakpoint on
1032 "B::func", only. A parameter has been added to the Python
1033 gdb.Breakpoint constructor to achieve the same result when creating
1034 a breakpoint from Python.
1036 * Breakpoints on functions marked with C++ ABI tags
1038 GDB can now set breakpoints on functions marked with C++ ABI tags
1039 (e.g., [abi:cxx11]). See here for a description of ABI tags:
1040 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
1042 Functions with a C++11 abi tag are demangled/displayed like this:
1044 function[abi:cxx11](int)
1047 You can now set a breakpoint on such functions simply as if they had
1050 (gdb) b function(int)
1052 Or if you need to disambiguate between tags, like:
1054 (gdb) b function[abi:other_tag](int)
1056 Tab completion was adjusted accordingly as well.
1060 ** New events gdb.new_inferior, gdb.inferior_deleted, and
1061 gdb.new_thread are emitted. See the manual for further
1062 description of these.
1064 ** A new function, "gdb.rbreak" has been added to the Python API.
1065 This function allows the setting of a large number of breakpoints
1066 via a regex pattern in Python. See the manual for further details.
1068 ** Python breakpoints can now accept explicit locations. See the
1069 manual for a further description of this feature.
1072 * New features in the GDB remote stub, GDBserver
1074 ** GDBserver is now able to start inferior processes with a
1075 specified initial working directory.
1077 The user can set the desired working directory to be used from
1078 GDB using the new "set cwd" command.
1080 ** New "--selftest" command line option runs some GDBserver self
1081 tests. These self tests are disabled in releases.
1083 ** On Unix systems, GDBserver now does globbing expansion and variable
1084 substitution in inferior command line arguments.
1086 This is done by starting inferiors using a shell, like GDB does.
1087 See "set startup-with-shell" in the user manual for how to disable
1088 this from GDB when using "target extended-remote". When using
1089 "target remote", you can disable the startup with shell by using the
1090 new "--no-startup-with-shell" GDBserver command line option.
1092 ** On Unix systems, GDBserver now supports receiving environment
1093 variables that are to be set or unset from GDB. These variables
1094 will affect the environment to be passed to the inferior.
1096 * When catching an Ada exception raised with a message, GDB now prints
1097 the message in the catchpoint hit notification. In GDB/MI mode, that
1098 information is provided as an extra field named "exception-message"
1099 in the *stopped notification.
1101 * Trait objects can now be inspected When debugging Rust code. This
1102 requires compiler support which will appear in Rust 1.24.
1104 * New remote packets
1106 QEnvironmentHexEncoded
1107 Inform GDBserver of an environment variable that is to be passed to
1108 the inferior when starting it.
1111 Inform GDBserver of an environment variable that is to be unset
1112 before starting the remote inferior.
1115 Inform GDBserver that the environment should be reset (i.e.,
1116 user-set environment variables should be unset).
1119 Indicates whether the inferior must be started with a shell or not.
1122 Tell GDBserver that the inferior to be started should use a specific
1125 * The "maintenance print c-tdesc" command now takes an optional
1126 argument which is the file name of XML target description.
1128 * The "maintenance selftest" command now takes an optional argument to
1129 filter the tests to be run.
1131 * The "enable", and "disable" commands now accept a range of
1132 breakpoint locations, e.g. "enable 1.3-5".
1137 Set and show the current working directory for the inferior.
1139 set|show compile-gcc
1140 Set and show compilation command used for compiling and injecting code
1141 with the 'compile' commands.
1143 set debug separate-debug-file
1144 show debug separate-debug-file
1145 Control the display of debug output about separate debug file search.
1147 set dump-excluded-mappings
1148 show dump-excluded-mappings
1149 Control whether mappings marked with the VM_DONTDUMP flag should be
1150 dumped when generating a core file.
1152 maint info selftests
1153 List the registered selftests.
1156 Start the debugged program stopping at the first instruction.
1159 Control display of debugging messages related to OpenRISC targets.
1161 set|show print type nested-type-limit
1162 Set and show the limit of nesting level for nested types that the
1163 type printer will show.
1165 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
1168 * Safer/improved support for debugging with no debug info
1170 GDB no longer assumes functions with no debug information return
1173 This means that GDB now refuses to call such functions unless you
1174 tell it the function's type, by either casting the call to the
1175 declared return type, or by casting the function to a function
1176 pointer of the right type, and calling that:
1178 (gdb) p getenv ("PATH")
1179 'getenv' has unknown return type; cast the call to its declared return type
1180 (gdb) p (char *) getenv ("PATH")
1181 $1 = 0x7fffffffe "/usr/local/bin:/"...
1182 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
1183 $2 = 0x7fffffffe "/usr/local/bin:/"...
1185 Similarly, GDB no longer assumes that global variables with no debug
1186 info have type 'int', and refuses to print the variable's value
1187 unless you tell it the variable's type:
1190 'var' has unknown type; cast it to its declared type
1194 * New native configurations
1196 FreeBSD/aarch64 aarch64*-*-freebsd*
1197 FreeBSD/arm arm*-*-freebsd*
1201 FreeBSD/aarch64 aarch64*-*-freebsd*
1202 FreeBSD/arm arm*-*-freebsd*
1203 OpenRISC ELF or1k*-*-elf
1205 * Removed targets and native configurations
1207 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
1209 *** Changes in GDB 8.0
1211 * GDB now supports access to the PKU register on GNU/Linux. The register is
1212 added by the Memory Protection Keys for Userspace feature which will be
1213 available in future Intel CPUs.
1215 * GDB now supports C++11 rvalue references.
1219 ** New functions to start, stop and access a running btrace recording.
1220 ** Rvalue references are now supported in gdb.Type.
1222 * GDB now supports recording and replaying rdrand and rdseed Intel 64
1225 * Building GDB and GDBserver now requires a C++11 compiler.
1227 For example, GCC 4.8 or later.
1229 It is no longer possible to build GDB or GDBserver with a C
1230 compiler. The --disable-build-with-cxx configure option has been
1233 * Building GDB and GDBserver now requires GNU make >= 3.81.
1235 It is no longer supported to build GDB or GDBserver with another
1236 implementation of the make program or an earlier version of GNU make.
1238 * Native debugging on MS-Windows supports command-line redirection
1240 Command-line arguments used for starting programs on MS-Windows can
1241 now include redirection symbols supported by native Windows shells,
1242 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
1243 as "run", "start", and "set args", as well as the corresponding MI
1246 * Support for thread names on MS-Windows.
1248 GDB now catches and handles the special exception that programs
1249 running on MS-Windows use to assign names to threads in the
1252 * Support for Java programs compiled with gcj has been removed.
1254 * User commands now accept an unlimited number of arguments.
1255 Previously, only up to 10 was accepted.
1257 * The "eval" command now expands user-defined command arguments.
1259 This makes it easier to process a variable number of arguments:
1264 eval "print $arg%d", $i
1269 * Target descriptions can now describe registers for sparc32 and sparc64.
1271 * GDB now supports DWARF version 5 (debug information format).
1272 Its .debug_names index is not yet supported.
1274 * New native configurations
1276 FreeBSD/mips mips*-*-freebsd
1280 Synopsys ARC arc*-*-elf32
1281 FreeBSD/mips mips*-*-freebsd
1283 * Removed targets and native configurations
1285 Alpha running FreeBSD alpha*-*-freebsd*
1286 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
1291 Erases all the flash memory regions reported by the target.
1293 maint print arc arc-instruction address
1294 Print internal disassembler information about instruction at a given address.
1298 set disassembler-options
1299 show disassembler-options
1300 Controls the passing of target specific information to the disassembler.
1301 If it is necessary to specify more than one disassembler option then
1302 multiple options can be placed together into a comma separated list.
1303 The default value is the empty string. Currently, the only supported
1304 targets are ARM, PowerPC and S/390.
1309 Erases all the flash memory regions reported by the target. This is
1310 equivalent to the CLI command flash-erase.
1312 -file-list-shared-libraries
1313 List the shared libraries in the program. This is
1314 equivalent to the CLI command "info shared".
1317 Catchpoints stopping the program when Ada exceptions are
1318 handled. This is equivalent to the CLI command "catch handlers".
1320 *** Changes in GDB 7.12
1322 * GDB and GDBserver now build with a C++ compiler by default.
1324 The --enable-build-with-cxx configure option is now enabled by
1325 default. One must now explicitly configure with
1326 --disable-build-with-cxx in order to build with a C compiler. This
1327 option will be removed in a future release.
1329 * GDBserver now supports recording btrace without maintaining an active
1332 * GDB now supports a negative repeat count in the 'x' command to examine
1333 memory backward from the given address. For example:
1336 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
1337 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
1338 (gdb) x/-5i 0x0000000000400580
1339 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
1340 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
1341 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
1342 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
1343 0x40057b <main(int, char**)+25>:
1344 callq 0x400536 <Func1(int, char const*)>
1346 * Fortran: Support structures with fields of dynamic types and
1347 arrays of dynamic types.
1349 * The symbol dumping maintenance commands have new syntax.
1350 maint print symbols [-pc address] [--] [filename]
1351 maint print symbols [-objfile objfile] [-source source] [--] [filename]
1352 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
1353 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
1354 maint print msymbols [-objfile objfile] [--] [filename]
1356 * GDB now supports multibit bitfields and enums in target register
1359 * New Python-based convenience function $_as_string(val), which returns
1360 the textual representation of a value. This function is especially
1361 useful to obtain the text label of an enum value.
1363 * Intel MPX bound violation handling.
1365 Segmentation faults caused by a Intel MPX boundary violation
1366 now display the kind of violation (upper or lower), the memory
1367 address accessed and the memory bounds, along with the usual
1368 signal received and code location.
1372 Program received signal SIGSEGV, Segmentation fault
1373 Upper bound violation while accessing address 0x7fffffffc3b3
1374 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
1375 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
1377 * Rust language support.
1378 GDB now supports debugging programs written in the Rust programming
1379 language. See https://www.rust-lang.org/ for more information about
1382 * Support for running interpreters on specified input/output devices
1384 GDB now supports a new mechanism that allows frontends to provide
1385 fully featured GDB console views, as a better alternative to
1386 building such views on top of the "-interpreter-exec console"
1387 command. See the new "new-ui" command below. With that command,
1388 frontends can now start GDB in the traditional command-line mode
1389 running in an embedded terminal emulator widget, and create a
1390 separate MI interpreter running on a specified i/o device. In this
1391 way, GDB handles line editing, history, tab completion, etc. in the
1392 console all by itself, and the GUI uses the separate MI interpreter
1393 for its own control and synchronization, invisible to the command
1396 * The "catch syscall" command catches groups of related syscalls.
1398 The "catch syscall" command now supports catching a group of related
1399 syscalls using the 'group:' or 'g:' prefix.
1404 skip -gfile file-glob-pattern
1405 skip -function function
1406 skip -rfunction regular-expression
1407 A generalized form of the skip command, with new support for
1408 glob-style file names and regular expressions for function names.
1409 Additionally, a file spec and a function spec may now be combined.
1411 maint info line-table REGEXP
1412 Display the contents of GDB's internal line table data structure.
1415 Run any GDB unit tests that were compiled in.
1418 Start a new user interface instance running INTERP as interpreter,
1419 using the TTY file for input/output.
1423 ** gdb.Breakpoint objects have a new attribute "pending", which
1424 indicates whether the breakpoint is pending.
1425 ** Three new breakpoint-related events have been added:
1426 gdb.breakpoint_created, gdb.breakpoint_modified, and
1427 gdb.breakpoint_deleted.
1429 signal-event EVENTID
1430 Signal ("set") the given MS-Windows event object. This is used in
1431 conjunction with the Windows JIT debugging (AeDebug) support, where
1432 the OS suspends a crashing process until a debugger can attach to
1433 it. Resuming the crashing process, in order to debug it, is done by
1434 signalling an event.
1436 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
1437 was added in GDBserver, including JIT compiling fast tracepoint's
1438 conditional expression bytecode into native code.
1440 * Support for various remote target protocols and ROM monitors has
1443 target m32rsdi Remote M32R debugging over SDI
1444 target mips MIPS remote debugging protocol
1445 target pmon PMON ROM monitor
1446 target ddb NEC's DDB variant of PMON for Vr4300
1447 target rockhopper NEC RockHopper variant of PMON
1448 target lsi LSI variant of PMO
1450 * Support for tracepoints and fast tracepoints on powerpc-linux,
1451 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
1452 including JIT compiling fast tracepoint's conditional expression
1453 bytecode into native code.
1455 * MI async record =record-started now includes the method and format used for
1456 recording. For example:
1458 =record-started,thread-group="i1",method="btrace",format="bts"
1460 * MI async record =thread-selected now includes the frame field. For example:
1462 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
1466 Andes NDS32 nds32*-*-elf
1468 *** Changes in GDB 7.11
1470 * GDB now supports debugging kernel-based threads on FreeBSD.
1472 * Per-inferior thread numbers
1474 Thread numbers are now per inferior instead of global. If you're
1475 debugging multiple inferiors, GDB displays thread IDs using a
1476 qualified INF_NUM.THR_NUM form. For example:
1480 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
1481 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1482 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1483 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1485 As consequence, thread numbers as visible in the $_thread
1486 convenience variable and in Python's InferiorThread.num attribute
1487 are no longer unique between inferiors.
1489 GDB now maintains a second thread ID per thread, referred to as the
1490 global thread ID, which is the new equivalent of thread numbers in
1491 previous releases. See also $_gthread below.
1493 For backwards compatibility, MI's thread IDs always refer to global
1496 * Commands that accept thread IDs now accept the qualified
1497 INF_NUM.THR_NUM form as well. For example:
1500 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1503 * In commands that accept a list of thread IDs, you can now refer to
1504 all threads of an inferior using a star wildcard. GDB accepts
1505 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1506 refer to all threads of the current inferior. For example, "info
1509 * You can use "info threads -gid" to display the global thread ID of
1512 * The new convenience variable $_gthread holds the global number of
1515 * The new convenience variable $_inferior holds the number of the
1518 * GDB now displays the ID and name of the thread that hit a breakpoint
1519 or received a signal, if your program is multi-threaded. For
1522 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1523 Thread 1 "main" received signal SIGINT, Interrupt.
1525 * Record btrace now supports non-stop mode.
1527 * Support for tracepoints on aarch64-linux was added in GDBserver.
1529 * The 'record instruction-history' command now indicates speculative execution
1530 when using the Intel Processor Trace recording format.
1532 * GDB now allows users to specify explicit locations, bypassing
1533 the linespec parser. This feature is also available to GDB/MI
1536 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1537 GDB now is able to debug both AArch64 applications and ARM applications
1540 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1541 including JIT compiling fast tracepoint's conditional expression bytecode
1544 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1546 * "info threads", "info inferiors", "info display", "info checkpoints"
1547 and "maint info program-spaces" now list the corresponding items in
1548 ascending ID order, for consistency with all other "info" commands.
1550 * In Ada, the overloads selection menu has been enhanced to display the
1551 parameter types and the return types for the matching overloaded subprograms.
1555 maint set target-non-stop (on|off|auto)
1556 maint show target-non-stop
1557 Control whether GDB targets always operate in non-stop mode even if
1558 "set non-stop" is "off". The default is "auto", meaning non-stop
1559 mode is enabled if supported by the target.
1561 maint set bfd-sharing
1562 maint show bfd-sharing
1563 Control the reuse of bfd objects.
1566 show debug bfd-cache
1567 Control display of debugging info regarding bfd caching.
1571 Control display of debugging info regarding FreeBSD threads.
1573 set remote multiprocess-extensions-packet
1574 show remote multiprocess-extensions-packet
1575 Set/show the use of the remote protocol multiprocess extensions.
1577 set remote thread-events
1578 show remote thread-events
1579 Set/show the use of thread create/exit events.
1581 set ada print-signatures on|off
1582 show ada print-signatures"
1583 Control whether parameter types and return types are displayed in overloads
1584 selection menus. It is activated (@code{on}) by default.
1588 Controls the maximum size of memory, in bytes, that GDB will
1589 allocate for value contents. Prevents incorrect programs from
1590 causing GDB to allocate overly large buffers. Default is 64k.
1592 * The "disassemble" command accepts a new modifier: /s.
1593 It prints mixed source+disassembly like /m with two differences:
1594 - disassembled instructions are now printed in program order, and
1595 - and source for all relevant files is now printed.
1596 The "/m" option is now considered deprecated: its "source-centric"
1597 output hasn't proved useful in practice.
1599 * The "record instruction-history" command accepts a new modifier: /s.
1600 It behaves exactly like /m and prints mixed source+disassembly.
1602 * The "set scheduler-locking" command supports a new mode "replay".
1603 It behaves like "off" in record mode and like "on" in replay mode.
1605 * Support for various ROM monitors has been removed:
1607 target dbug dBUG ROM monitor for Motorola ColdFire
1608 target picobug Motorola picobug monitor
1609 target dink32 DINK32 ROM monitor for PowerPC
1610 target m32r Renesas M32R/D ROM monitor
1611 target mon2000 mon2000 ROM monitor
1612 target ppcbug PPCBUG ROM monitor for PowerPC
1614 * Support for reading/writing memory and extracting values on architectures
1615 whose memory is addressable in units of any integral multiple of 8 bits.
1618 Allows to break when an Ada exception is handled.
1620 * New remote packets
1623 Indicates that an exec system call was executed.
1625 exec-events feature in qSupported
1626 The qSupported packet allows GDB to request support for exec
1627 events using the new 'gdbfeature' exec-event, and the qSupported
1628 response can contain the corresponding 'stubfeature'. Set and
1629 show commands can be used to display whether these features are enabled.
1632 Equivalent to interrupting with the ^C character, but works in
1635 thread created stop reason (T05 create:...)
1636 Indicates that the thread was just created and is stopped at entry.
1638 thread exit stop reply (w exitcode;tid)
1639 Indicates that the thread has terminated.
1642 Enables/disables thread create and exit event reporting. For
1643 example, this is used in non-stop mode when GDB stops a set of
1644 threads and synchronously waits for the their corresponding stop
1645 replies. Without exit events, if one of the threads exits, GDB
1646 would hang forever not knowing that it should no longer expect a
1647 stop for that same thread.
1650 Indicates that there are no resumed threads left in the target (all
1651 threads are stopped). The remote stub reports support for this stop
1652 reply to GDB's qSupported query.
1655 Enables/disables catching syscalls from the inferior process.
1656 The remote stub reports support for this packet to GDB's qSupported query.
1658 syscall_entry stop reason
1659 Indicates that a syscall was just called.
1661 syscall_return stop reason
1662 Indicates that a syscall just returned.
1664 * Extended-remote exec events
1666 ** GDB now has support for exec events on extended-remote Linux targets.
1667 For such targets with Linux kernels 2.5.46 and later, this enables
1668 follow-exec-mode and exec catchpoints.
1670 set remote exec-event-feature-packet
1671 show remote exec-event-feature-packet
1672 Set/show the use of the remote exec event feature.
1674 * Thread names in remote protocol
1676 The reply to qXfer:threads:read may now include a name attribute for each
1679 * Target remote mode fork and exec events
1681 ** GDB now has support for fork and exec events on target remote mode
1682 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1683 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1684 fork and exec catchpoints.
1686 * Remote syscall events
1688 ** GDB now has support for catch syscall on remote Linux targets,
1689 currently enabled on x86/x86_64 architectures.
1691 set remote catch-syscall-packet
1692 show remote catch-syscall-packet
1693 Set/show the use of the remote catch syscall feature.
1697 ** The -var-set-format command now accepts the zero-hexadecimal
1698 format. It outputs data in hexadecimal format with zero-padding on the
1703 ** gdb.InferiorThread objects have a new attribute "global_num",
1704 which refers to the thread's global thread ID. The existing
1705 "num" attribute now refers to the thread's per-inferior number.
1706 See "Per-inferior thread numbers" above.
1707 ** gdb.InferiorThread objects have a new attribute "inferior", which
1708 is the Inferior object the thread belongs to.
1710 *** Changes in GDB 7.10
1712 * Support for process record-replay and reverse debugging on aarch64*-linux*
1713 targets has been added. GDB now supports recording of A64 instruction set
1714 including advance SIMD instructions.
1716 * Support for Sun's version of the "stabs" debug file format has been removed.
1718 * GDB now honors the content of the file /proc/PID/coredump_filter
1719 (PID is the process ID) on GNU/Linux systems. This file can be used
1720 to specify the types of memory mappings that will be included in a
1721 corefile. For more information, please refer to the manual page of
1722 "core(5)". GDB also has a new command: "set use-coredump-filter
1723 on|off". It allows to set whether GDB will read the content of the
1724 /proc/PID/coredump_filter file when generating a corefile.
1726 * The "info os" command on GNU/Linux can now display information on
1728 "info os cpus" Listing of all cpus/cores on the system
1730 * GDB has two new commands: "set serial parity odd|even|none" and
1731 "show serial parity". These allows to set or show parity for the
1734 * The "info source" command now displays the producer string if it was
1735 present in the debug info. This typically includes the compiler version
1736 and may include things like its command line arguments.
1738 * The "info dll", an alias of the "info sharedlibrary" command,
1739 is now available on all platforms.
1741 * Directory names supplied to the "set sysroot" commands may be
1742 prefixed with "target:" to tell GDB to access shared libraries from
1743 the target system, be it local or remote. This replaces the prefix
1744 "remote:". The default sysroot has been changed from "" to
1745 "target:". "remote:" is automatically converted to "target:" for
1746 backward compatibility.
1748 * The system root specified by "set sysroot" will be prepended to the
1749 filename of the main executable (if reported to GDB as absolute by
1750 the operating system) when starting processes remotely, and when
1751 attaching to already-running local or remote processes.
1753 * GDB now supports automatic location and retrieval of executable
1754 files from remote targets. Remote debugging can now be initiated
1755 using only a "target remote" or "target extended-remote" command
1756 (no "set sysroot" or "file" commands are required). See "New remote
1759 * The "dump" command now supports verilog hex format.
1761 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
1763 * On GNU/Linux, GDB and gdbserver are now able to access executable
1764 and shared library files without a "set sysroot" command when
1765 attaching to processes running in different mount namespaces from
1766 the debugger. This makes it possible to attach to processes in
1767 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
1768 See "New remote packets" below.
1770 * The "tui reg" command now provides completion for all of the
1771 available register groups, including target specific groups.
1773 * The HISTSIZE environment variable is no longer read when determining
1774 the size of GDB's command history. GDB now instead reads the dedicated
1775 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
1776 disables truncation of command history. Non-numeric values of GDBHISTSIZE
1781 ** Memory ports can now be unbuffered.
1785 ** gdb.Objfile objects have a new attribute "username",
1786 which is the name of the objfile as specified by the user,
1787 without, for example, resolving symlinks.
1788 ** You can now write frame unwinders in Python.
1789 ** gdb.Type objects have a new method "optimized_out",
1790 returning optimized out gdb.Value instance of this type.
1791 ** gdb.Value objects have new methods "reference_value" and
1792 "const_value" which return a reference to the value and a
1793 "const" version of the value respectively.
1797 maint print symbol-cache
1798 Print the contents of the symbol cache.
1800 maint print symbol-cache-statistics
1801 Print statistics of symbol cache usage.
1803 maint flush-symbol-cache
1804 Flush the contents of the symbol cache.
1808 Start branch trace recording using Branch Trace Store (BTS) format.
1811 Evaluate expression by using the compiler and print result.
1815 Explicit commands for enabling and disabling tui mode.
1818 set mpx bound on i386 and amd64
1819 Support for bound table investigation on Intel MPX enabled applications.
1823 Start branch trace recording using Intel Processor Trace format.
1826 Print information about branch tracing internals.
1828 maint btrace packet-history
1829 Print the raw branch tracing data.
1831 maint btrace clear-packet-history
1832 Discard the stored raw branch tracing data.
1835 Discard all branch tracing data. It will be fetched and processed
1836 anew by the next "record" command.
1841 Renamed from "set debug dwarf2-die".
1842 show debug dwarf-die
1843 Renamed from "show debug dwarf2-die".
1845 set debug dwarf-read
1846 Renamed from "set debug dwarf2-read".
1847 show debug dwarf-read
1848 Renamed from "show debug dwarf2-read".
1850 maint set dwarf always-disassemble
1851 Renamed from "maint set dwarf2 always-disassemble".
1852 maint show dwarf always-disassemble
1853 Renamed from "maint show dwarf2 always-disassemble".
1855 maint set dwarf max-cache-age
1856 Renamed from "maint set dwarf2 max-cache-age".
1857 maint show dwarf max-cache-age
1858 Renamed from "maint show dwarf2 max-cache-age".
1860 set debug dwarf-line
1861 show debug dwarf-line
1862 Control display of debugging info regarding DWARF line processing.
1865 show max-completions
1866 Set the maximum number of candidates to be considered during
1867 completion. The default value is 200. This limit allows GDB
1868 to avoid generating large completion lists, the computation of
1869 which can cause the debugger to become temporarily unresponsive.
1871 set history remove-duplicates
1872 show history remove-duplicates
1873 Control the removal of duplicate history entries.
1875 maint set symbol-cache-size
1876 maint show symbol-cache-size
1877 Control the size of the symbol cache.
1879 set|show record btrace bts buffer-size
1880 Set and show the size of the ring buffer used for branch tracing in
1882 The obtained size may differ from the requested size. Use "info
1883 record" to see the obtained buffer size.
1885 set debug linux-namespaces
1886 show debug linux-namespaces
1887 Control display of debugging info regarding Linux namespaces.
1889 set|show record btrace pt buffer-size
1890 Set and show the size of the ring buffer used for branch tracing in
1891 Intel Processor Trace format.
1892 The obtained size may differ from the requested size. Use "info
1893 record" to see the obtained buffer size.
1895 maint set|show btrace pt skip-pad
1896 Set and show whether PAD packets are skipped when computing the
1899 * The command 'thread apply all' can now support new option '-ascending'
1900 to call its specified command for all threads in ascending order.
1902 * Python/Guile scripting
1904 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1905 special section named `.debug_gdb_scripts'.
1907 * New remote packets
1909 qXfer:btrace-conf:read
1910 Return the branch trace configuration for the current thread.
1912 Qbtrace-conf:bts:size
1913 Set the requested ring buffer size for branch tracing in BTS format.
1916 Enable Intel Processor Trace-based branch tracing for the current
1917 process. The remote stub reports support for this packet to GDB's
1920 Qbtrace-conf:pt:size
1921 Set the requested ring buffer size for branch tracing in Intel Processor
1925 Indicates a memory breakpoint instruction was executed, irrespective
1926 of whether it was GDB that planted the breakpoint or the breakpoint
1927 is hardcoded in the program. This is required for correct non-stop
1931 Indicates the target stopped for a hardware breakpoint. This is
1932 required for correct non-stop mode operation.
1935 Return information about files on the remote system.
1937 qXfer:exec-file:read
1938 Return the full absolute name of the file that was executed to
1939 create a process running on the remote system.
1942 Select the filesystem on which vFile: operations with filename
1943 arguments will operate. This is required for GDB to be able to
1944 access files on remote targets where the remote stub does not
1945 share a common filesystem with the inferior(s).
1948 Indicates that a fork system call was executed.
1951 Indicates that a vfork system call was executed.
1953 vforkdone stop reason
1954 Indicates that a vfork child of the specified process has executed
1955 an exec or exit, allowing the vfork parent to resume execution.
1957 fork-events and vfork-events features in qSupported
1958 The qSupported packet allows GDB to request support for fork and
1959 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1960 and the qSupported response can contain the corresponding
1961 'stubfeatures'. Set and show commands can be used to display
1962 whether these features are enabled.
1964 * Extended-remote fork events
1966 ** GDB now has support for fork events on extended-remote Linux
1967 targets. For targets with Linux kernels 2.5.60 and later, this
1968 enables follow-fork-mode and detach-on-fork for both fork and
1969 vfork, as well as fork and vfork catchpoints.
1971 * The info record command now shows the recording format and the
1972 branch tracing configuration for the current thread when using
1973 the btrace record target.
1974 For the BTS format, it shows the ring buffer size.
1976 * GDB now has support for DTrace USDT (Userland Static Defined
1977 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1979 * GDB now supports access to vector registers on S/390 GNU/Linux
1982 * Removed command line options
1984 -xdb HP-UX XDB compatibility mode.
1986 * Removed targets and native configurations
1988 HP/PA running HP-UX hppa*-*-hpux*
1989 Itanium running HP-UX ia64-*-hpux*
1991 * New configure options
1994 This configure option allows the user to build GDB with support for
1995 Intel Processor Trace (default: auto). This requires libipt.
1997 --with-libipt-prefix=PATH
1998 Specify the path to the version of libipt that GDB should use.
1999 $PATH/include should contain the intel-pt.h header and
2000 $PATH/lib should contain the libipt.so library.
2002 *** Changes in GDB 7.9.1
2006 ** Xmethods can now specify a result type.
2008 *** Changes in GDB 7.9
2010 * GDB now supports hardware watchpoints on x86 GNU Hurd.
2014 ** You can now access frame registers from Python scripts.
2015 ** New attribute 'producer' for gdb.Symtab objects.
2016 ** gdb.Objfile objects have a new attribute "progspace",
2017 which is the gdb.Progspace object of the containing program space.
2018 ** gdb.Objfile objects have a new attribute "owner".
2019 ** gdb.Objfile objects have a new attribute "build_id",
2020 which is the build ID generated when the file was built.
2021 ** gdb.Objfile objects have a new method "add_separate_debug_file".
2022 ** A new event "gdb.clear_objfiles" has been added, triggered when
2023 selecting a new file to debug.
2024 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
2025 ** New function gdb.lookup_objfile.
2027 New events which are triggered when GDB modifies the state of the
2030 ** gdb.events.inferior_call_pre: Function call is about to be made.
2031 ** gdb.events.inferior_call_post: Function call has just been made.
2032 ** gdb.events.memory_changed: A memory location has been altered.
2033 ** gdb.events.register_changed: A register has been altered.
2035 * New Python-based convenience functions:
2037 ** $_caller_is(name [, number_of_frames])
2038 ** $_caller_matches(regexp [, number_of_frames])
2039 ** $_any_caller_is(name [, number_of_frames])
2040 ** $_any_caller_matches(regexp [, number_of_frames])
2042 * GDB now supports the compilation and injection of source code into
2043 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
2044 to compile the source code to object code, and if successful, inject
2045 and execute that code within the current context of the inferior.
2046 Currently the C language is supported. The commands used to
2047 interface with this new feature are:
2049 compile code [-raw|-r] [--] [source code]
2050 compile file [-raw|-r] filename
2054 demangle [-l language] [--] name
2055 Demangle "name" in the specified language, or the current language
2056 if elided. This command is renamed from the "maint demangle" command.
2057 The latter is kept as a no-op to avoid "maint demangle" being interpreted
2058 as "maint demangler-warning".
2060 queue-signal signal-name-or-number
2061 Queue a signal to be delivered to the thread when it is resumed.
2063 add-auto-load-scripts-directory directory
2064 Add entries to the list of directories from which to load auto-loaded
2067 maint print user-registers
2068 List all currently available "user" registers.
2070 compile code [-r|-raw] [--] [source code]
2071 Compile, inject, and execute in the inferior the executable object
2072 code produced by compiling the provided source code.
2074 compile file [-r|-raw] filename
2075 Compile and inject into the inferior the executable object code
2076 produced by compiling the source code stored in the filename
2079 * On resume, GDB now always passes the signal the program had stopped
2080 for to the thread the signal was sent to, even if the user changed
2081 threads before resuming. Previously GDB would often (but not
2082 always) deliver the signal to the thread that happens to be current
2085 * Conversely, the "signal" command now consistently delivers the
2086 requested signal to the current thread. GDB now asks for
2087 confirmation if the program had stopped for a signal and the user
2088 switched threads meanwhile.
2090 * "breakpoint always-inserted" modes "off" and "auto" merged.
2092 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
2093 won't remove breakpoints from the target until all threads stop,
2094 even in non-stop mode. The "auto" mode has been removed, and "off"
2095 is now the default mode.
2099 set debug symbol-lookup
2100 show debug symbol-lookup
2101 Control display of debugging info regarding symbol lookup.
2105 ** The -list-thread-groups command outputs an exit-code field for
2106 inferiors that have exited.
2110 MIPS SDE mips*-sde*-elf*
2114 Support for these obsolete configurations has been removed.
2116 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
2117 SGI Irix-5.x mips-*-irix5*
2118 SGI Irix-6.x mips-*-irix6*
2119 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
2120 VAX running Ultrix vax-*-ultrix*
2122 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2123 and "assf"), have been removed. Use the "sharedlibrary" command, or
2124 its alias "share", instead.
2126 *** Changes in GDB 7.8
2128 * New command line options
2131 This is an alias for the --data-directory option.
2133 * GDB supports printing and modifying of variable length automatic arrays
2134 as specified in ISO C99.
2136 * The ARM simulator now supports instruction level tracing
2137 with or without disassembly.
2141 GDB now has support for scripting using Guile. Whether this is
2142 available is determined at configure time.
2143 Guile version 2.0 or greater is required.
2144 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
2146 * New commands (for set/show, see "New options" below)
2150 Invoke CODE by passing it to the Guile interpreter.
2154 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
2156 info auto-load guile-scripts [regexp]
2157 Print the list of automatically loaded Guile scripts.
2159 * The source command is now capable of sourcing Guile scripts.
2160 This feature is dependent on the debugger being built with Guile support.
2164 set print symbol-loading (off|brief|full)
2165 show print symbol-loading
2166 Control whether to print informational messages when loading symbol
2167 information for a file. The default is "full", but when debugging
2168 programs with large numbers of shared libraries the amount of output
2169 becomes less useful.
2171 set guile print-stack (none|message|full)
2172 show guile print-stack
2173 Show a stack trace when an error is encountered in a Guile script.
2175 set auto-load guile-scripts (on|off)
2176 show auto-load guile-scripts
2177 Control auto-loading of Guile script files.
2179 maint ada set ignore-descriptive-types (on|off)
2180 maint ada show ignore-descriptive-types
2181 Control whether the debugger should ignore descriptive types in Ada
2182 programs. The default is not to ignore the descriptive types. See
2183 the user manual for more details on descriptive types and the intended
2184 usage of this option.
2186 set auto-connect-native-target
2188 Control whether GDB is allowed to automatically connect to the
2189 native target for the run, attach, etc. commands when not connected
2190 to any target yet. See also "target native" below.
2192 set record btrace replay-memory-access (read-only|read-write)
2193 show record btrace replay-memory-access
2194 Control what memory accesses are allowed during replay.
2196 maint set target-async (on|off)
2197 maint show target-async
2198 This controls whether GDB targets operate in synchronous or
2199 asynchronous mode. Normally the default is asynchronous, if it is
2200 available; but this can be changed to more easily debug problems
2201 occurring only in synchronous mode.
2203 set mi-async (on|off)
2205 Control whether MI asynchronous mode is preferred. This supersedes
2206 "set target-async" of previous GDB versions.
2208 * "set target-async" is deprecated as a CLI option and is now an alias
2209 for "set mi-async" (only puts MI into async mode).
2211 * Background execution commands (e.g., "c&", "s&", etc.) are now
2212 possible ``out of the box'' if the target supports them. Previously
2213 the user would need to explicitly enable the possibility with the
2214 "set target-async on" command.
2216 * New features in the GDB remote stub, GDBserver
2218 ** New option --debug-format=option1[,option2,...] allows one to add
2219 additional text to each output. At present only timestamps
2220 are supported: --debug-format=timestamps.
2221 Timestamps can also be turned on with the
2222 "monitor set debug-format timestamps" command from GDB.
2224 * The 'record instruction-history' command now starts counting instructions
2225 at one. This also affects the instruction ranges reported by the
2226 'record function-call-history' command when given the /i modifier.
2228 * The command 'record function-call-history' supports a new modifier '/c' to
2229 indent the function names based on their call stack depth.
2230 The fields for the '/i' and '/l' modifier have been reordered.
2231 The source line range is now prefixed with 'at'.
2232 The instruction range is now prefixed with 'inst'.
2233 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
2234 "record instruction-history" and "list" commands.
2236 * The ranges given as arguments to the 'record function-call-history' and
2237 'record instruction-history' commands are now inclusive.
2239 * The btrace record target now supports the 'record goto' command.
2240 For locations inside the execution trace, the back trace is computed
2241 based on the information stored in the execution trace.
2243 * The btrace record target supports limited reverse execution and replay.
2244 The target does not record data and therefore does not allow reading
2245 memory or registers.
2247 * The "catch syscall" command now works on s390*-linux* targets.
2249 * The "compare-sections" command is no longer specific to target
2250 remote. It now works with all targets.
2252 * All native targets are now consistently called "native".
2253 Consequently, the "target child", "target GNU", "target djgpp",
2254 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
2255 commands have been replaced with "target native". The QNX/NTO port
2256 leaves the "procfs" target in place and adds a "native" target for
2257 consistency with other ports. The impact on users should be minimal
2258 as these commands previously either throwed an error, or were
2259 no-ops. The target's name is visible in the output of the following
2260 commands: "help target", "info target", "info files", "maint print
2263 * The "target native" command now connects to the native target. This
2264 can be used to launch native programs even when "set
2265 auto-connect-native-target" is set to off.
2267 * GDB now supports access to Intel MPX registers on GNU/Linux.
2269 * Support for Intel AVX-512 registers on GNU/Linux.
2270 Support displaying and modifying Intel AVX-512 registers
2271 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
2273 * New remote packets
2275 qXfer:btrace:read's annex
2276 The qXfer:btrace:read packet supports a new annex 'delta' to read
2277 branch trace incrementally.
2281 ** Valid Python operations on gdb.Value objects representing
2282 structs/classes invoke the corresponding overloaded operators if
2284 ** New `Xmethods' feature in the Python API. Xmethods are
2285 additional methods or replacements for existing methods of a C++
2286 class. This feature is useful for those cases where a method
2287 defined in C++ source code could be inlined or optimized out by
2288 the compiler, making it unavailable to GDB.
2291 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
2293 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2294 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
2295 its alias "share", instead.
2297 * The commands "set remotebaud" and "show remotebaud" are no longer
2298 supported. Use "set serial baud" and "show serial baud" (respectively)
2303 ** A new option "-gdb-set mi-async" replaces "-gdb-set
2304 target-async". The latter is left as a deprecated alias of the
2305 former for backward compatibility. If the target supports it,
2306 CLI background execution commands are now always possible by
2307 default, independently of whether the frontend stated a
2308 preference for asynchronous execution with "-gdb-set mi-async".
2309 Previously "-gdb-set target-async off" affected both MI execution
2310 commands and CLI execution commands.
2312 *** Changes in GDB 7.7
2314 * Improved support for process record-replay and reverse debugging on
2315 arm*-linux* targets. Support for thumb32 and syscall instruction
2316 recording has been added.
2318 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
2320 * GDB now supports Fission DWP file format version 2.
2321 http://gcc.gnu.org/wiki/DebugFission
2323 * New convenience function "$_isvoid", to check whether an expression
2324 is void. A void expression is an expression where the type of the
2325 result is "void". For example, some convenience variables may be
2326 "void" when evaluated (e.g., "$_exitcode" before the execution of
2327 the program being debugged; or an undefined convenience variable).
2328 Another example, when calling a function whose return type is
2331 * The "maintenance print objfiles" command now takes an optional regexp.
2333 * The "catch syscall" command now works on arm*-linux* targets.
2335 * GDB now consistently shows "<not saved>" when printing values of
2336 registers the debug info indicates have not been saved in the frame
2337 and there's nowhere to retrieve them from
2338 (callee-saved/call-clobbered registers):
2343 (gdb) info registers rax
2346 Before, the former would print "<optimized out>", and the latter
2347 "*value not available*".
2349 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
2354 ** Frame filters and frame decorators have been added.
2355 ** Temporary breakpoints are now supported.
2356 ** Line tables representation has been added.
2357 ** New attribute 'parent_type' for gdb.Field objects.
2358 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
2359 ** New attribute 'name' for gdb.Type objects.
2363 Nios II ELF nios2*-*-elf
2364 Nios II GNU/Linux nios2*-*-linux
2365 Texas Instruments MSP430 msp430*-*-elf
2367 * Removed native configurations
2369 Support for these a.out NetBSD and OpenBSD obsolete configurations has
2370 been removed. ELF variants of these configurations are kept supported.
2372 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
2373 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
2374 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
2375 i[34567]86-*-openbsd3.[0-3]
2376 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
2377 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
2378 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
2382 Like "catch throw", but catches a re-thrown exception.
2383 maint check-psymtabs
2384 Renamed from old "maint check-symtabs".
2386 Perform consistency checks on symtabs.
2387 maint expand-symtabs
2388 Expand symtabs matching an optional regexp.
2391 Display the details of GDB configure-time options.
2393 maint set|show per-command
2394 maint set|show per-command space
2395 maint set|show per-command time
2396 maint set|show per-command symtab
2397 Enable display of per-command gdb resource usage.
2399 remove-symbol-file FILENAME
2400 remove-symbol-file -a ADDRESS
2401 Remove a symbol file added via add-symbol-file. The file to remove
2402 can be identified by its filename or by an address that lies within
2403 the boundaries of this symbol file in memory.
2406 info exceptions REGEXP
2407 Display the list of Ada exceptions defined in the program being
2408 debugged. If provided, only the exceptions whose names match REGEXP
2413 set debug symfile off|on
2415 Control display of debugging info regarding reading symbol files and
2416 symbol tables within those files
2418 set print raw frame-arguments
2419 show print raw frame-arguments
2420 Set/show whether to print frame arguments in raw mode,
2421 disregarding any defined pretty-printers.
2423 set remote trace-status-packet
2424 show remote trace-status-packet
2425 Set/show the use of remote protocol qTStatus packet.
2429 Control display of debugging messages related to Nios II targets.
2433 Control whether target-assisted range stepping is enabled.
2435 set startup-with-shell
2436 show startup-with-shell
2437 Specifies whether Unix child processes are started via a shell or
2442 Use the target memory cache for accesses to the code segment. This
2443 improves performance of remote debugging (particularly disassembly).
2445 * You can now use a literal value 'unlimited' for options that
2446 interpret 0 or -1 as meaning "unlimited". E.g., "set
2447 trace-buffer-size unlimited" is now an alias for "set
2448 trace-buffer-size -1" and "set height unlimited" is now an alias for
2451 * The "set debug symtab-create" debugging option of GDB has been changed to
2452 accept a verbosity level. 0 means "off", 1 provides basic debugging
2453 output, and values of 2 or greater provides more verbose output.
2455 * New command-line options
2457 Display the details of GDB configure-time options.
2459 * The command 'tsave' can now support new option '-ctf' to save trace
2460 buffer in Common Trace Format.
2462 * Newly installed $prefix/bin/gcore acts as a shell interface for the
2465 * GDB now implements the C++ 'typeid' operator.
2467 * The new convenience variable $_exception holds the exception being
2468 thrown or caught at an exception-related catchpoint.
2470 * The exception-related catchpoints, like "catch throw", now accept a
2471 regular expression which can be used to filter exceptions by type.
2473 * The new convenience variable $_exitsignal is automatically set to
2474 the terminating signal number when the program being debugged dies
2475 due to an uncaught signal.
2479 ** All MI commands now accept an optional "--language" option.
2480 Support for this feature can be verified by using the "-list-features"
2481 command, which should contain "language-option".
2483 ** The new command -info-gdb-mi-command allows the user to determine
2484 whether a GDB/MI command is supported or not.
2486 ** The "^error" result record returned when trying to execute an undefined
2487 GDB/MI command now provides a variable named "code" whose content is the
2488 "undefined-command" error code. Support for this feature can be verified
2489 by using the "-list-features" command, which should contain
2490 "undefined-command-error-code".
2492 ** The -trace-save MI command can optionally save trace buffer in Common
2495 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2497 ** The command -data-list-register-values now accepts an optional
2498 "--skip-unavailable" option. When used, only the available registers
2501 ** The new command -trace-frame-collected dumps collected variables,
2502 computed expressions, tvars, memory and registers in a traceframe.
2504 ** The commands -stack-list-locals, -stack-list-arguments and
2505 -stack-list-variables now accept an option "--skip-unavailable".
2506 When used, only the available locals or arguments are displayed.
2508 ** The -exec-run command now accepts an optional "--start" option.
2509 When used, the command follows the same semantics as the "start"
2510 command, stopping the program's execution at the start of its
2511 main subprogram. Support for this feature can be verified using
2512 the "-list-features" command, which should contain
2513 "exec-run-start-option".
2515 ** The new commands -catch-assert and -catch-exceptions insert
2516 catchpoints stopping the program when Ada exceptions are raised.
2518 ** The new command -info-ada-exceptions provides the equivalent of
2519 the new "info exceptions" command.
2521 * New system-wide configuration scripts
2522 A GDB installation now provides scripts suitable for use as system-wide
2523 configuration scripts for the following systems:
2527 * GDB now supports target-assigned range stepping with remote targets.
2528 This improves the performance of stepping source lines by reducing
2529 the number of control packets from/to GDB. See "New remote packets"
2532 * GDB now understands the element 'tvar' in the XML traceframe info.
2533 It has the id of the collected trace state variables.
2535 * On S/390 targets that provide the transactional-execution feature,
2536 the program interruption transaction diagnostic block (TDB) is now
2537 represented as a number of additional "registers" in GDB.
2539 * New remote packets
2543 The vCont packet supports a new 'r' action, that tells the remote
2544 stub to step through an address range itself, without GDB
2545 involvemement at each single-step.
2547 qXfer:libraries-svr4:read's annex
2548 The previously unused annex of the qXfer:libraries-svr4:read packet
2549 is now used to support passing an argument list. The remote stub
2550 reports support for this argument list to GDB's qSupported query.
2551 The defined arguments are "start" and "prev", used to reduce work
2552 necessary for library list updating, resulting in significant
2555 * New features in the GDB remote stub, GDBserver
2557 ** GDBserver now supports target-assisted range stepping. Currently
2558 enabled on x86/x86_64 GNU/Linux targets.
2560 ** GDBserver now adds element 'tvar' in the XML in the reply to
2561 'qXfer:traceframe-info:read'. It has the id of the collected
2562 trace state variables.
2564 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2567 * New 'z' formatter for printing and examining memory, this displays the
2568 value as hexadecimal zero padded on the left to the size of the type.
2570 * GDB can now use Windows x64 unwinding data.
2572 * The "set remotebaud" command has been replaced by "set serial baud".
2573 Similarly, "show remotebaud" has been replaced by "show serial baud".
2574 The "set remotebaud" and "show remotebaud" commands are still available
2575 to provide backward compatibility with older versions of GDB.
2577 *** Changes in GDB 7.6
2579 * Target record has been renamed to record-full.
2580 Record/replay is now enabled with the "record full" command.
2581 This also affects settings that are associated with full record/replay
2582 that have been moved from "set/show record" to "set/show record full":
2584 set|show record full insn-number-max
2585 set|show record full stop-at-limit
2586 set|show record full memory-query
2588 * A new record target "record-btrace" has been added. The new target
2589 uses hardware support to record the control-flow of a process. It
2590 does not support replaying the execution, but it implements the
2591 below new commands for investigating the recorded execution log.
2592 This new recording method can be enabled using:
2596 The "record-btrace" target is only available on Intel Atom processors
2597 and requires a Linux kernel 2.6.32 or later.
2599 * Two new commands have been added for record/replay to give information
2600 about the recorded execution without having to replay the execution.
2601 The commands are only supported by "record btrace".
2603 record instruction-history prints the execution history at
2604 instruction granularity
2606 record function-call-history prints the execution history at
2607 function granularity
2609 * New native configurations
2611 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2612 FreeBSD/powerpc powerpc*-*-freebsd
2613 x86_64/Cygwin x86_64-*-cygwin*
2614 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2618 ARM AArch64 aarch64*-*-elf
2619 ARM AArch64 GNU/Linux aarch64*-*-linux
2620 Lynx 178 PowerPC powerpc-*-lynx*178
2621 x86_64/Cygwin x86_64-*-cygwin*
2622 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2624 * If the configured location of system.gdbinit file (as given by the
2625 --with-system-gdbinit option at configure time) is in the
2626 data-directory (as specified by --with-gdb-datadir at configure
2627 time) or in one of its subdirectories, then GDB will look for the
2628 system-wide init file in the directory specified by the
2629 --data-directory command-line option.
2631 * New command line options:
2633 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2634 other initialization files, unlike -nx which disables all of them.
2636 * Removed command line options
2638 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2641 * The 'ptype' and 'whatis' commands now accept an argument to control
2644 * 'info proc' now works on some core files.
2648 ** Vectors can be created with gdb.Type.vector.
2650 ** Python's atexit.register now works in GDB.
2652 ** Types can be pretty-printed via a Python API.
2654 ** Python 3 is now supported (in addition to Python 2.4 or later)
2656 ** New class gdb.Architecture exposes GDB's internal representation
2657 of architecture in the Python API.
2659 ** New method Frame.architecture returns the gdb.Architecture object
2660 corresponding to the frame's architecture.
2662 * New Python-based convenience functions:
2664 ** $_memeq(buf1, buf2, length)
2665 ** $_streq(str1, str2)
2667 ** $_regex(str, regex)
2669 * The 'cd' command now defaults to using '~' (the home directory) if not
2672 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2673 default for GCC since November 2000.
2675 * The command 'forward-search' can now be abbreviated as 'fo'.
2677 * The command 'info tracepoints' can now display 'installed on target'
2678 or 'not installed on target' for each non-pending location of tracepoint.
2680 * New configure options
2682 --enable-libmcheck/--disable-libmcheck
2683 By default, development versions are built with -lmcheck on hosts
2684 that support it, in order to help track memory corruption issues.
2685 Release versions, on the other hand, are built without -lmcheck
2686 by default. The --enable-libmcheck/--disable-libmcheck configure
2687 options allow the user to override that default.
2688 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2689 This configure option allows the user to build GDB with
2690 libbabeltrace using which GDB can read Common Trace Format data.
2692 * New commands (for set/show, see "New options" below)
2695 Catch signals. This is similar to "handle", but allows commands and
2696 conditions to be attached.
2699 List the BFDs known to GDB.
2701 python-interactive [command]
2703 Start a Python interactive prompt, or evaluate the optional command
2704 and print the result of expressions.
2707 "py" is a new alias for "python".
2709 enable type-printer [name]...
2710 disable type-printer [name]...
2711 Enable or disable type printers.
2715 ** For the Renesas Super-H architecture, the "regs" command has been removed
2716 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2721 set print type methods (on|off)
2722 show print type methods
2723 Control whether method declarations are displayed by "ptype".
2724 The default is to show them.
2726 set print type typedefs (on|off)
2727 show print type typedefs
2728 Control whether typedef definitions are displayed by "ptype".
2729 The default is to show them.
2731 set filename-display basename|relative|absolute
2732 show filename-display
2733 Control the way in which filenames is displayed.
2734 The default is "relative", which preserves previous behavior.
2736 set trace-buffer-size
2737 show trace-buffer-size
2738 Request target to change the size of trace buffer.
2740 set remote trace-buffer-size-packet auto|on|off
2741 show remote trace-buffer-size-packet
2742 Control the use of the remote protocol `QTBuffer:size' packet.
2746 Control display of debugging messages related to ARM AArch64.
2749 set debug coff-pe-read
2750 show debug coff-pe-read
2751 Control display of debugging messages related to reading of COFF/PE
2756 Control display of debugging messages related to Mach-O symbols
2759 set debug notification
2760 show debug notification
2761 Control display of debugging info for async remote notification.
2765 ** Command parameter changes are now notified using new async record
2766 "=cmd-param-changed".
2767 ** Trace frame changes caused by command "tfind" are now notified using
2768 new async record "=traceframe-changed".
2769 ** The creation, deletion and modification of trace state variables
2770 are now notified using new async records "=tsv-created",
2771 "=tsv-deleted" and "=tsv-modified".
2772 ** The start and stop of process record are now notified using new
2773 async record "=record-started" and "=record-stopped".
2774 ** Memory changes are now notified using new async record
2776 ** The data-disassemble command response will include a "fullname" field
2777 containing the absolute file name when source has been requested.
2778 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
2779 command, to allow pattern filling of memory areas.
2780 ** New commands "-catch-load"/"-catch-unload" added for intercepting
2781 library load/unload events.
2782 ** The response to breakpoint commands and breakpoint async records
2783 includes an "installed" field containing a boolean state about each
2784 non-pending tracepoint location is whether installed on target or not.
2785 ** Output of the "-trace-status" command includes a "trace-file" field
2786 containing the name of the trace file being examined. This field is
2787 optional, and only present when examining a trace file.
2788 ** The "fullname" field is now always present along with the "file" field,
2789 even if the file cannot be found by GDB.
2791 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
2792 You must have the LZMA library available when configuring GDB for this
2793 feature to be enabled. For more information, see:
2794 http://fedoraproject.org/wiki/Features/MiniDebugInfo
2796 * New remote packets
2799 Set the size of trace buffer. The remote stub reports support for this
2800 packet to gdb's qSupported query.
2803 Enable Branch Trace Store (BTS)-based branch tracing for the current
2804 thread. The remote stub reports support for this packet to gdb's
2808 Disable branch tracing for the current thread. The remote stub reports
2809 support for this packet to gdb's qSupported query.
2812 Read the traced branches for the current thread. The remote stub
2813 reports support for this packet to gdb's qSupported query.
2815 *** Changes in GDB 7.5
2817 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2818 for more x32 ABI info.
2820 * GDB now supports access to MIPS DSP registers on Linux targets.
2822 * GDB now supports debugging microMIPS binaries.
2824 * The "info os" command on GNU/Linux can now display information on
2825 several new classes of objects managed by the operating system:
2826 "info os procgroups" lists process groups
2827 "info os files" lists file descriptors
2828 "info os sockets" lists internet-domain sockets
2829 "info os shm" lists shared-memory regions
2830 "info os semaphores" lists semaphores
2831 "info os msg" lists message queues
2832 "info os modules" lists loaded kernel modules
2834 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2835 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2836 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2837 options and inspect the probe arguments using the new $_probe_arg family
2838 of convenience variables. You can obtain more information about SystemTap
2839 in <http://sourceware.org/systemtap/>.
2841 * GDB now supports reversible debugging on ARM, it allows you to
2842 debug basic ARM and THUMB instructions, and provides
2843 record/replay support.
2845 * The option "symbol-reloading" has been deleted as it is no longer used.
2849 ** GDB commands implemented in Python can now be put in command class
2852 ** The "maint set python print-stack on|off" is now deleted.
2854 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
2855 apply "flag enum"-style pretty-printing to any enum.
2857 ** gdb.lookup_symbol can now work when there is no current frame.
2859 ** gdb.Symbol now has a 'line' attribute, holding the line number in
2860 the source at which the symbol was defined.
2862 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
2863 method 'value'. The former indicates whether the symbol needs a
2864 frame in order to compute its value, and the latter computes the
2867 ** A new method 'referenced_value' on gdb.Value objects which can
2868 dereference pointer as well as C++ reference values.
2870 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
2871 which return the global and static blocks (as gdb.Block objects),
2872 of the underlying symbol table, respectively.
2874 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2875 object associated with a PC value.
2877 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2878 of the address range occupied by code for the current source line.
2880 * Go language support.
2881 GDB now supports debugging programs written in the Go programming
2884 * GDBserver now supports stdio connections.
2885 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2887 * The binary "gdbtui" can no longer be built or installed.
2888 Use "gdb -tui" instead.
2890 * GDB will now print "flag" enums specially. A flag enum is one where
2891 all the enumerator values have no bits in common when pairwise
2892 "and"ed. When printing a value whose type is a flag enum, GDB will
2893 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2894 (gdb) print (enum E) 3
2897 * The filename part of a linespec will now match trailing components
2898 of a source file name. For example, "break gcc/expr.c:1000" will
2899 now set a breakpoint in build/gcc/expr.c, but not
2900 build/libcpp/expr.c.
2902 * The "info proc" and "generate-core-file" commands will now also
2903 work on remote targets connected to GDBserver on Linux.
2905 * The command "info catch" has been removed. It has been disabled
2906 since December 2007.
2908 * The "catch exception" and "catch assert" commands now accept
2909 a condition at the end of the command, much like the "break"
2910 command does. For instance:
2912 (gdb) catch exception Constraint_Error if Barrier = True
2914 Previously, it was possible to add a condition to such catchpoints,
2915 but it had to be done as a second step, after the catchpoint had been
2916 created, using the "condition" command.
2918 * The "info static-tracepoint-marker" command will now also work on
2919 native Linux targets with in-process agent.
2921 * GDB can now set breakpoints on inlined functions.
2923 * The .gdb_index section has been updated to include symbols for
2924 inlined functions. GDB will ignore older .gdb_index sections by
2925 default, which could cause symbol files to be loaded more slowly
2926 until their .gdb_index sections can be recreated. The new command
2927 "set use-deprecated-index-sections on" will cause GDB to use any older
2928 .gdb_index sections it finds. This will restore performance, but the
2929 ability to set breakpoints on inlined functions will be lost in symbol
2930 files with older .gdb_index sections.
2932 The .gdb_index section has also been updated to record more information
2933 about each symbol. This speeds up the "info variables", "info functions"
2934 and "info types" commands when used with programs having the .gdb_index
2935 section, as well as speeding up debugging with shared libraries using
2936 the .gdb_index section.
2938 * Ada support for GDB/MI Variable Objects has been added.
2940 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2945 ** New command -info-os is the MI equivalent of "info os".
2947 ** Output logs ("set logging" and related) now include MI output.
2951 ** "set use-deprecated-index-sections on|off"
2952 "show use-deprecated-index-sections on|off"
2953 Controls the use of deprecated .gdb_index sections.
2955 ** "catch load" and "catch unload" can be used to stop when a shared
2956 library is loaded or unloaded, respectively.
2958 ** "enable count" can be used to auto-disable a breakpoint after
2961 ** "info vtbl" can be used to show the virtual method tables for
2962 C++ and Java objects.
2964 ** "explore" and its sub commands "explore value" and "explore type"
2965 can be used to recursively explore values and types of
2966 expressions. These commands are available only if GDB is
2967 configured with '--with-python'.
2969 ** "info auto-load" shows status of all kinds of auto-loaded files,
2970 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2971 sequences of commands files, "info auto-load python-scripts"
2972 shows status of auto-loading Python script files,
2973 "info auto-load local-gdbinit" shows status of loading init file
2974 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2975 status of inferior specific thread debugging shared library loading.
2977 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2978 and "show auto-load-scripts" commands have been deprecated, use their
2979 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2980 and "show auto-load python-scripts" counterparts instead.
2982 ** "dprintf location,format,args..." creates a dynamic printf, which
2983 is basically a breakpoint that does a printf and immediately
2984 resumes your program's execution, so it is like a printf that you
2985 can insert dynamically at runtime instead of at compiletime.
2987 ** "set print symbol"
2989 Controls whether GDB attempts to display the symbol, if any,
2990 corresponding to addresses it prints. This defaults to "on", but
2991 you can set it to "off" to restore GDB's previous behavior.
2993 * Deprecated commands
2995 ** For the Renesas Super-H architecture, the "regs" command has been
2996 deprecated, and "info all-registers" should be used instead.
3000 Renesas RL78 rl78-*-elf
3001 HP OpenVMS ia64 ia64-hp-openvms*
3003 * GDBserver supports evaluation of breakpoint conditions. When
3004 support is advertised by GDBserver, GDB may be told to send the
3005 breakpoint conditions in bytecode form to GDBserver. GDBserver
3006 will only report the breakpoint trigger to GDB when its condition
3011 set mips compression
3012 show mips compression
3013 Select the compressed ISA encoding used in functions that have no symbol
3014 information available. The encoding can be set to either of:
3017 and is updated automatically from ELF file flags if available.
3019 set breakpoint condition-evaluation
3020 show breakpoint condition-evaluation
3021 Control whether breakpoint conditions are evaluated by GDB ("host") or by
3022 GDBserver ("target"). Default option "auto" chooses the most efficient
3024 This option can improve debugger efficiency depending on the speed of the
3028 Disable auto-loading globally.
3031 Show auto-loading setting of all kinds of auto-loaded files.
3033 set auto-load gdb-scripts on|off
3034 show auto-load gdb-scripts
3035 Control auto-loading of GDB canned sequences of commands files.
3037 set auto-load python-scripts on|off
3038 show auto-load python-scripts
3039 Control auto-loading of Python script files.
3041 set auto-load local-gdbinit on|off
3042 show auto-load local-gdbinit
3043 Control loading of init file (.gdbinit) from current directory.
3045 set auto-load libthread-db on|off
3046 show auto-load libthread-db
3047 Control auto-loading of inferior specific thread debugging shared library.
3049 set auto-load scripts-directory <dir1>[:<dir2>...]
3050 show auto-load scripts-directory
3051 Set a list of directories from which to load auto-loaded scripts.
3052 Automatically loaded Python scripts and GDB scripts are located in one
3053 of the directories listed by this option.
3054 The delimiter (':' above) may differ according to the host platform.
3056 set auto-load safe-path <dir1>[:<dir2>...]
3057 show auto-load safe-path
3058 Set a list of directories from which it is safe to auto-load files.
3059 The delimiter (':' above) may differ according to the host platform.
3061 set debug auto-load on|off
3062 show debug auto-load
3063 Control display of debugging info for auto-loading the files above.
3065 set dprintf-style gdb|call|agent
3067 Control the way in which a dynamic printf is performed; "gdb"
3068 requests a GDB printf command, while "call" causes dprintf to call a
3069 function in the inferior. "agent" requests that the target agent
3070 (such as GDBserver) do the printing.
3072 set dprintf-function <expr>
3073 show dprintf-function
3074 set dprintf-channel <expr>
3075 show dprintf-channel
3076 Set the function and optional first argument to the call when using
3077 the "call" style of dynamic printf.
3079 set disconnected-dprintf on|off
3080 show disconnected-dprintf
3081 Control whether agent-style dynamic printfs continue to be in effect
3082 after GDB disconnects.
3084 * New configure options
3086 --with-auto-load-dir
3087 Configure default value for the 'set auto-load scripts-directory'
3088 setting above. It defaults to '$debugdir:$datadir/auto-load',
3089 $debugdir representing global debugging info directories (available
3090 via 'show debug-file-directory') and $datadir representing GDB's data
3091 directory (available via 'show data-directory').
3093 --with-auto-load-safe-path
3094 Configure default value for the 'set auto-load safe-path' setting
3095 above. It defaults to the --with-auto-load-dir setting.
3097 --without-auto-load-safe-path
3098 Set 'set auto-load safe-path' to '/', effectively disabling this
3101 * New remote packets
3103 z0/z1 conditional breakpoints extension
3105 The z0/z1 breakpoint insertion packets have been extended to carry
3106 a list of conditional expressions over to the remote stub depending on the
3107 condition evaluation mode. The use of this extension can be controlled
3108 via the "set remote conditional-breakpoints-packet" command.
3112 Specify the signals which the remote stub may pass to the debugged
3113 program without GDB involvement.
3115 * New command line options
3117 --init-command=FILE, -ix Like --command, -x but execute it
3118 before loading inferior.
3119 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
3120 execute it before loading inferior.
3122 *** Changes in GDB 7.4
3124 * GDB now handles ambiguous linespecs more consistently; the existing
3125 FILE:LINE support has been expanded to other types of linespecs. A
3126 breakpoint will now be set on all matching locations in all
3127 inferiors, and locations will be added or removed according to
3130 * GDB now allows you to skip uninteresting functions and files when
3131 stepping with the "skip function" and "skip file" commands.
3133 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
3134 and "show remote hardware-watchpoint-length-limit". These allows to
3135 set or show the maximum length limit (in bytes) of a remote
3136 target hardware watchpoint.
3138 This allows e.g. to use "unlimited" hardware watchpoints with the
3139 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
3140 watchpoints are slower than real hardware watchpoints but are
3141 significantly faster than gdb software watchpoints.
3145 ** The register_pretty_printer function in module gdb.printing now takes
3146 an optional `replace' argument. If True, the new printer replaces any
3149 ** The "maint set python print-stack on|off" command has been
3150 deprecated and will be deleted in GDB 7.5.
3151 A new command: "set python print-stack none|full|message" has
3152 replaced it. Additionally, the default for "print-stack" is
3153 now "message", which just prints the error message without
3156 ** A prompt substitution hook (prompt_hook) is now available to the
3159 ** A new Python module, gdb.prompt has been added to the GDB Python
3160 modules library. This module provides functionality for
3161 escape sequences in prompts (used by set/show
3162 extended-prompt). These escape sequences are replaced by their
3163 corresponding value.
3165 ** Python commands and convenience-functions located in
3166 'data-directory'/python/gdb/command and
3167 'data-directory'/python/gdb/function are now automatically loaded
3170 ** Blocks now provide four new attributes. global_block and
3171 static_block will return the global and static blocks
3172 respectively. is_static and is_global are boolean attributes
3173 that indicate if the block is one of those two types.
3175 ** Symbols now provide the "type" attribute, the type of the symbol.
3177 ** The "gdb.breakpoint" function has been deprecated in favor of
3180 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
3181 of a function. This class is based on the "finish" command
3182 available in the CLI.
3184 ** Type objects for struct and union types now allow access to
3185 the fields using standard Python dictionary (mapping) methods.
3186 For example, "some_type['myfield']" now works, as does
3187 "some_type.items()".
3189 ** A new event "gdb.new_objfile" has been added, triggered by loading a
3192 ** A new function, "deep_items" has been added to the gdb.types
3193 module in the GDB Python modules library. This function returns
3194 an iterator over the fields of a struct or union type. Unlike
3195 the standard Python "iteritems" method, it will recursively traverse
3196 any anonymous fields.
3200 ** "*stopped" events can report several new "reason"s, such as
3203 ** Breakpoint changes are now notified using new async records, like
3204 "=breakpoint-modified".
3206 ** New command -ada-task-info.
3208 * libthread-db-search-path now supports two special values: $sdir and $pdir.
3209 $sdir specifies the default system locations of shared libraries.
3210 $pdir specifies the directory where the libpthread used by the application
3213 GDB no longer looks in $sdir and $pdir after it has searched the directories
3214 mentioned in libthread-db-search-path. If you want to search those
3215 directories, they must be specified in libthread-db-search-path.
3216 The default value of libthread-db-search-path on GNU/Linux and Solaris
3217 systems is now "$sdir:$pdir".
3219 $pdir is not supported by gdbserver, it is currently ignored.
3220 $sdir is supported by gdbserver.
3222 * New configure option --with-iconv-bin.
3223 When using the internationalization support like the one in the GNU C
3224 library, GDB will invoke the "iconv" program to get a list of supported
3225 character sets. If this program lives in a non-standard location, one can
3226 use this option to specify where to find it.
3228 * When natively debugging programs on PowerPC BookE processors running
3229 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
3230 watchpoints, which specify a mask in addition to an address to watch.
3231 The mask specifies that some bits of an address (the bits which are
3232 reset in the mask) should be ignored when matching the address accessed
3233 by the inferior against the watchpoint address. See the "PowerPC Embedded"
3234 section in the user manual for more details.
3236 * The new option --once causes GDBserver to stop listening for connections once
3237 the first connection is made. The listening port used by GDBserver will
3238 become available after that.
3240 * New commands "info macros" and "alias" have been added.
3242 * New function parameters suffix @entry specifies value of function parameter
3243 at the time the function got called. Entry values are available only since
3249 "!" is now an alias of the "shell" command.
3250 Note that no space is needed between "!" and SHELL COMMAND.
3254 watch EXPRESSION mask MASK_VALUE
3255 The watch command now supports the mask argument which allows creation
3256 of masked watchpoints, if the current architecture supports this feature.
3258 info auto-load-scripts [REGEXP]
3259 This command was formerly named "maintenance print section-scripts".
3260 It is now generally useful and is no longer a maintenance-only command.
3262 info macro [-all] [--] MACRO
3263 The info macro command has new options `-all' and `--'. The first for
3264 printing all definitions of a macro. The second for explicitly specifying
3265 the end of arguments and the beginning of the macro name in case the macro
3266 name starts with a hyphen.
3268 collect[/s] EXPRESSIONS
3269 The tracepoint collect command now takes an optional modifier "/s"
3270 that directs it to dereference pointer-to-character types and
3271 collect the bytes of memory up to a zero byte. The behavior is
3272 similar to what you see when you use the regular print command on a
3273 string. An optional integer following the "/s" sets a bound on the
3274 number of bytes that will be collected.
3277 The trace start command now interprets any supplied arguments as a
3278 note to be recorded with the trace run, with an effect similar to
3279 setting the variable trace-notes.
3282 The trace stop command now interprets any arguments as a note to be
3283 mentioned along with the tstatus report that the trace was stopped
3284 with a command. The effect is similar to setting the variable
3287 * Tracepoints can now be enabled and disabled at any time after a trace
3288 experiment has been started using the standard "enable" and "disable"
3289 commands. It is now possible to start a trace experiment with no enabled
3290 tracepoints; GDB will display a warning, but will allow the experiment to
3291 begin, assuming that tracepoints will be enabled as needed while the trace
3294 * Fast tracepoints on 32-bit x86-architectures can now be placed at
3295 locations with 4-byte instructions, when they were previously
3296 limited to locations with instructions of 5 bytes or longer.
3300 set debug dwarf2-read
3301 show debug dwarf2-read
3302 Turns on or off display of debugging messages related to reading
3303 DWARF debug info. The default is off.
3305 set debug symtab-create
3306 show debug symtab-create
3307 Turns on or off display of debugging messages related to symbol table
3308 creation. The default is off.
3311 show extended-prompt
3312 Set the GDB prompt, and allow escape sequences to be inserted to
3313 display miscellaneous information (see 'help set extended-prompt'
3314 for the list of sequences). This prompt (and any information
3315 accessed through the escape sequences) is updated every time the
3316 prompt is displayed.
3318 set print entry-values (both|compact|default|if-needed|no|only|preferred)
3319 show print entry-values
3320 Set printing of frame argument values at function entry. In some cases
3321 GDB can determine the value of function argument which was passed by the
3322 function caller, even if the value was modified inside the called function.
3324 set debug entry-values
3325 show debug entry-values
3326 Control display of debugging info for determining frame argument values at
3327 function entry and virtual tail call frames.
3329 set basenames-may-differ
3330 show basenames-may-differ
3331 Set whether a source file may have multiple base names.
3332 (A "base name" is the name of a file with the directory part removed.
3333 Example: The base name of "/home/user/hello.c" is "hello.c".)
3334 If set, GDB will canonicalize file names (e.g., expand symlinks)
3335 before comparing them. Canonicalization is an expensive operation,
3336 but it allows the same file be known by more than one base name.
3337 If not set (the default), all source files are assumed to have just
3338 one base name, and gdb will do file name comparisons more efficiently.
3344 Set a user name and notes for the current and any future trace runs.
3345 This is useful for long-running and/or disconnected traces, to
3346 inform others (or yourself) as to who is running the trace, supply
3347 contact information, or otherwise explain what is going on.
3349 set trace-stop-notes
3350 show trace-stop-notes
3351 Set a note attached to the trace run, that is displayed when the
3352 trace has been stopped by a tstop command. This is useful for
3353 instance as an explanation, if you are stopping a trace run that was
3354 started by someone else.
3356 * New remote packets
3360 Dynamically enable a tracepoint in a started trace experiment.
3364 Dynamically disable a tracepoint in a started trace experiment.
3368 Set the user and notes of the trace run.
3372 Query the current status of a tracepoint.
3376 Query the minimum length of instruction at which a fast tracepoint may
3379 * Dcache size (number of lines) and line-size are now runtime-configurable
3380 via "set dcache line" and "set dcache line-size" commands.
3384 Texas Instruments TMS320C6x tic6x-*-*
3388 Renesas RL78 rl78-*-elf
3390 *** Changes in GDB 7.3.1
3392 * The build failure for NetBSD and OpenBSD targets have now been fixed.
3394 *** Changes in GDB 7.3
3396 * GDB has a new command: "thread find [REGEXP]".
3397 It finds the thread id whose name, target id, or thread extra info
3398 matches the given regular expression.
3400 * The "catch syscall" command now works on mips*-linux* targets.
3402 * The -data-disassemble MI command now supports modes 2 and 3 for
3403 dumping the instruction opcodes.
3405 * New command line options
3407 -data-directory DIR Specify DIR as the "data-directory".
3408 This is mostly for testing purposes.
3410 * The "maint set python auto-load on|off" command has been renamed to
3411 "set auto-load-scripts on|off".
3413 * GDB has a new command: "set directories".
3414 It is like the "dir" command except that it replaces the
3415 source path list instead of augmenting it.
3417 * GDB now understands thread names.
3419 On GNU/Linux, "info threads" will display the thread name as set by
3420 prctl or pthread_setname_np.
3422 There is also a new command, "thread name", which can be used to
3423 assign a name internally for GDB to display.
3426 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
3427 has been integrated into GDB.
3431 ** The function gdb.Write now accepts an optional keyword 'stream'.
3432 This keyword, when provided, will direct the output to either
3433 stdout, stderr, or GDB's logging output.
3435 ** Parameters can now be be sub-classed in Python, and in particular
3436 you may implement the get_set_doc and get_show_doc functions.
3437 This improves how Parameter set/show documentation is processed
3438 and allows for more dynamic content.
3440 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
3441 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
3442 have an is_valid method.
3444 ** Breakpoints can now be sub-classed in Python, and in particular
3445 you may implement a 'stop' function that is executed each time
3446 the inferior reaches that breakpoint.
3448 ** New function gdb.lookup_global_symbol looks up a global symbol.
3450 ** GDB values in Python are now callable if the value represents a
3451 function. For example, if 'some_value' represents a function that
3452 takes two integer parameters and returns a value, you can call
3453 that function like so:
3455 result = some_value (10,20)
3457 ** Module gdb.types has been added.
3458 It contains a collection of utilities for working with gdb.Types objects:
3459 get_basic_type, has_field, make_enum_dict.
3461 ** Module gdb.printing has been added.
3462 It contains utilities for writing and registering pretty-printers.
3463 New classes: PrettyPrinter, SubPrettyPrinter,
3464 RegexpCollectionPrettyPrinter.
3465 New function: register_pretty_printer.
3467 ** New commands "info pretty-printers", "enable pretty-printer" and
3468 "disable pretty-printer" have been added.
3470 ** gdb.parameter("directories") is now available.
3472 ** New function gdb.newest_frame returns the newest frame in the
3475 ** The gdb.InferiorThread class has a new "name" attribute. This
3476 holds the thread's name.
3478 ** Python Support for Inferior events.
3479 Python scripts can add observers to be notified of events
3480 occurring in the process being debugged.
3481 The following events are currently supported:
3482 - gdb.events.cont Continue event.
3483 - gdb.events.exited Inferior exited event.
3484 - gdb.events.stop Signal received, and Breakpoint hit events.
3488 ** GDB now puts template parameters in scope when debugging in an
3489 instantiation. For example, if you have:
3491 template<int X> int func (void) { return X; }
3493 then if you step into func<5>, "print X" will show "5". This
3494 feature requires proper debuginfo support from the compiler; it
3495 was added to GCC 4.5.
3497 ** The motion commands "next", "finish", "until", and "advance" now
3498 work better when exceptions are thrown. In particular, GDB will
3499 no longer lose control of the inferior; instead, the GDB will
3500 stop the inferior at the point at which the exception is caught.
3501 This functionality requires a change in the exception handling
3502 code that was introduced in GCC 4.5.
3504 * GDB now follows GCC's rules on accessing volatile objects when
3505 reading or writing target state during expression evaluation.
3506 One notable difference to prior behavior is that "print x = 0"
3507 no longer generates a read of x; the value of the assignment is
3508 now always taken directly from the value being assigned.
3510 * GDB now has some support for using labels in the program's source in
3511 linespecs. For instance, you can use "advance label" to continue
3512 execution to a label.
3514 * GDB now has support for reading and writing a new .gdb_index
3515 section. This section holds a fast index of DWARF debugging
3516 information and can be used to greatly speed up GDB startup and
3517 operation. See the documentation for `save gdb-index' for details.
3519 * The "watch" command now accepts an optional "-location" argument.
3520 When used, this causes GDB to watch the memory referred to by the
3521 expression. Such a watchpoint is never deleted due to it going out
3524 * GDB now supports thread debugging of core dumps on GNU/Linux.
3526 GDB now activates thread debugging using the libthread_db library
3527 when debugging GNU/Linux core dumps, similarly to when debugging
3528 live processes. As a result, when debugging a core dump file, GDB
3529 is now able to display pthread_t ids of threads. For example, "info
3530 threads" shows the same output as when debugging the process when it
3531 was live. In earlier releases, you'd see something like this:
3534 * 1 LWP 6780 main () at main.c:10
3536 While now you see this:
3539 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3541 It is also now possible to inspect TLS variables when debugging core
3544 When debugging a core dump generated on a machine other than the one
3545 used to run GDB, you may need to point GDB at the correct
3546 libthread_db library with the "set libthread-db-search-path"
3547 command. See the user manual for more details on this command.
3549 * When natively debugging programs on PowerPC BookE processors running
3550 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3551 which stop execution of the inferior whenever it executes an instruction
3552 at any address within the specified range. See the "PowerPC Embedded"
3553 section in the user manual for more details.
3555 * New features in the GDB remote stub, GDBserver
3557 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3558 and i686 LynxOS (version 5.x).
3560 ** GDBserver is now supported on Blackfin Linux.
3562 * New native configurations
3564 ia64 HP-UX ia64-*-hpux*
3568 Analog Devices, Inc. Blackfin Processor bfin-*
3570 * Ada task switching is now supported on sparc-elf targets when
3571 debugging a program using the Ravenscar Profile. For more information,
3572 see the "Tasking Support when using the Ravenscar Profile" section
3573 in the GDB user manual.
3575 * Guile support was removed.
3577 * New features in the GNU simulator
3579 ** The --map-info flag lists all known core mappings.
3581 ** CFI flashes may be simulated via the "cfi" device.
3583 *** Changes in GDB 7.2
3585 * Shared library support for remote targets by default
3587 When GDB is configured for a generic, non-OS specific target, like
3588 for example, --target=arm-eabi or one of the many *-*-elf targets,
3589 GDB now queries remote stubs for loaded shared libraries using the
3590 `qXfer:libraries:read' packet. Previously, shared library support
3591 was always disabled for such configurations.
3595 ** Argument Dependent Lookup (ADL)
3597 In C++ ADL lookup directs function search to the namespaces of its
3598 arguments even if the namespace has not been imported.
3608 Here the compiler will search for `foo' in the namespace of 'b'
3609 and find A::foo. GDB now supports this. This construct is commonly
3610 used in the Standard Template Library for operators.
3612 ** Improved User Defined Operator Support
3614 In addition to member operators, GDB now supports lookup of operators
3615 defined in a namespace and imported with a `using' directive, operators
3616 defined in the global scope, operators imported implicitly from an
3617 anonymous namespace, and the ADL operators mentioned in the previous
3619 GDB now also supports proper overload resolution for all the previously
3620 mentioned flavors of operators.
3622 ** static const class members
3624 Printing of static const class members that are initialized in the
3625 class definition has been fixed.
3627 * Windows Thread Information Block access.
3629 On Windows targets, GDB now supports displaying the Windows Thread
3630 Information Block (TIB) structure. This structure is visible either
3631 by using the new command `info w32 thread-information-block' or, by
3632 dereferencing the new convenience variable named `$_tlb', a
3633 thread-specific pointer to the TIB. This feature is also supported
3634 when remote debugging using GDBserver.
3636 * Static tracepoints
3638 Static tracepoints are calls in the user program into a tracing
3639 library. One such library is a port of the LTTng kernel tracer to
3640 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3641 When debugging with GDBserver, GDB now supports combining the GDB
3642 tracepoint machinery with such libraries. For example: the user can
3643 use GDB to probe a static tracepoint marker (a call from the user
3644 program into the tracing library) with the new "strace" command (see
3645 "New commands" below). This creates a "static tracepoint" in the
3646 breakpoint list, that can be manipulated with the same feature set
3647 as fast and regular tracepoints. E.g., collect registers, local and
3648 global variables, collect trace state variables, and define
3649 tracepoint conditions. In addition, the user can collect extra
3650 static tracepoint marker specific data, by collecting the new
3651 $_sdata internal variable. When analyzing the trace buffer, you can
3652 inspect $_sdata like any other variable available to GDB. For more
3653 information, see the "Tracepoints" chapter in GDB user manual. New
3654 remote packets have been defined to support static tracepoints, see
3655 the "New remote packets" section below.
3657 * Better reconstruction of tracepoints after disconnected tracing
3659 GDB will attempt to download the original source form of tracepoint
3660 definitions when starting a trace run, and then will upload these
3661 upon reconnection to the target, resulting in a more accurate
3662 reconstruction of the tracepoints that are in use on the target.
3666 You can now exercise direct control over the ways that GDB can
3667 affect your program. For instance, you can disallow the setting of
3668 breakpoints, so that the program can run continuously (assuming
3669 non-stop mode). In addition, the "observer" variable is available
3670 to switch all of the different controls; in observer mode, GDB
3671 cannot affect the target's behavior at all, which is useful for
3672 tasks like diagnosing live systems in the field.
3674 * The new convenience variable $_thread holds the number of the
3677 * New remote packets
3681 Return the address of the Windows Thread Information Block of a given thread.
3685 In response to several of the tracepoint packets, the target may now
3686 also respond with a number of intermediate `qRelocInsn' request
3687 packets before the final result packet, to have GDB handle
3688 relocating an instruction to execute at a different address. This
3689 is particularly useful for stubs that support fast tracepoints. GDB
3690 reports support for this feature in the qSupported packet.
3694 List static tracepoint markers in the target program.
3698 List static tracepoint markers at a given address in the target
3701 qXfer:statictrace:read
3703 Read the static trace data collected (by a `collect $_sdata'
3704 tracepoint action). The remote stub reports support for this packet
3705 to gdb's qSupported query.
3709 Send the current settings of GDB's permission flags.
3713 Send part of the source (textual) form of a tracepoint definition,
3714 which includes location, conditional, and action list.
3716 * The source command now accepts a -s option to force searching for the
3717 script in the source search path even if the script name specifies
3720 * New features in the GDB remote stub, GDBserver
3722 - GDBserver now support tracepoints (including fast tracepoints, and
3723 static tracepoints). The feature is currently supported by the
3724 i386-linux and amd64-linux builds. See the "Tracepoints support
3725 in gdbserver" section in the manual for more information.
3727 GDBserver JIT compiles the tracepoint's conditional agent
3728 expression bytecode into native code whenever possible for low
3729 overhead dynamic tracepoints conditionals. For such tracepoints,
3730 an expression that examines program state is evaluated when the
3731 tracepoint is reached, in order to determine whether to capture
3732 trace data. If the condition is simple and false, processing the
3733 tracepoint finishes very quickly and no data is gathered.
3735 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3736 for static tracepoints support.
3738 - GDBserver now supports x86_64 Windows 64-bit debugging.
3740 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3741 it understands register description.
3743 * The --batch flag now disables pagination and queries.
3745 * X86 general purpose registers
3747 GDB now supports reading/writing byte, word and double-word x86
3748 general purpose registers directly. This means you can use, say,
3749 $ah or $ax to refer, respectively, to the byte register AH and
3750 16-bit word register AX that are actually portions of the 32-bit
3751 register EAX or 64-bit register RAX.
3753 * The `commands' command now accepts a range of breakpoints to modify.
3754 A plain `commands' following a command that creates multiple
3755 breakpoints affects all the breakpoints set by that command. This
3756 applies to breakpoints set by `rbreak', and also applies when a
3757 single `break' command creates multiple breakpoints (e.g.,
3758 breakpoints on overloaded c++ functions).
3760 * The `rbreak' command now accepts a filename specification as part of
3761 its argument, limiting the functions selected by the regex to those
3762 in the specified file.
3764 * Support for remote debugging Windows and SymbianOS shared libraries
3765 from Unix hosts has been improved. Non Windows GDB builds now can
3766 understand target reported file names that follow MS-DOS based file
3767 system semantics, such as file names that include drive letters and
3768 use the backslash character as directory separator. This makes it
3769 possible to transparently use the "set sysroot" and "set
3770 solib-search-path" on Unix hosts to point as host copies of the
3771 target's shared libraries. See the new command "set
3772 target-file-system-kind" described below, and the "Commands to
3773 specify files" section in the user manual for more information.
3777 eval template, expressions...
3778 Convert the values of one or more expressions under the control
3779 of the string template to a command line, and call it.
3781 set target-file-system-kind unix|dos-based|auto
3782 show target-file-system-kind
3783 Set or show the assumed file system kind for target reported file
3786 save breakpoints <filename>
3787 Save all current breakpoint definitions to a file suitable for use
3788 in a later debugging session. To read the saved breakpoint
3789 definitions, use the `source' command.
3791 `save tracepoints' is a new alias for `save-tracepoints'. The latter
3794 info static-tracepoint-markers
3795 Display information about static tracepoint markers in the target.
3797 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
3798 Define a static tracepoint by probing a marker at the given
3799 function, line, address, or marker ID.
3803 Enable and disable observer mode.
3805 set may-write-registers on|off
3806 set may-write-memory on|off
3807 set may-insert-breakpoints on|off
3808 set may-insert-tracepoints on|off
3809 set may-insert-fast-tracepoints on|off
3810 set may-interrupt on|off
3811 Set individual permissions for GDB effects on the target. Note that
3812 some of these settings can have undesirable or surprising
3813 consequences, particularly when changed in the middle of a session.
3814 For instance, disabling the writing of memory can prevent
3815 breakpoints from being inserted, cause single-stepping to fail, or
3816 even crash your program, if you disable after breakpoints have been
3817 inserted. However, GDB should not crash.
3819 set record memory-query on|off
3820 show record memory-query
3821 Control whether to stop the inferior if memory changes caused
3822 by an instruction cannot be recorded.
3827 The disassemble command now supports "start,+length" form of two arguments.
3831 ** GDB now provides a new directory location, called the python directory,
3832 where Python scripts written for GDB can be installed. The location
3833 of that directory is <data-directory>/python, where <data-directory>
3834 is the GDB data directory. For more details, see section `Scripting
3835 GDB using Python' in the manual.
3837 ** The GDB Python API now has access to breakpoints, symbols, symbol
3838 tables, program spaces, inferiors, threads and frame's code blocks.
3839 Additionally, GDB Parameters can now be created from the API, and
3840 manipulated via set/show in the CLI.
3842 ** New functions gdb.target_charset, gdb.target_wide_charset,
3843 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3845 ** New exception gdb.GdbError.
3847 ** Pretty-printers are now also looked up in the current program space.
3849 ** Pretty-printers can now be individually enabled and disabled.
3851 ** GDB now looks for names of Python scripts to auto-load in a
3852 special section named `.debug_gdb_scripts', in addition to looking
3853 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
3855 * Tracepoint actions were unified with breakpoint commands. In particular,
3856 there are no longer differences in "info break" output for breakpoints and
3857 tracepoints and the "commands" command can be used for both tracepoints and
3858 regular breakpoints.
3862 ARM Symbian arm*-*-symbianelf*
3864 * D language support.
3865 GDB now supports debugging programs written in the D programming
3868 * GDB now supports the extended ptrace interface for PowerPC which is
3869 available since Linux kernel version 2.6.34. This automatically enables
3870 any hardware breakpoints and additional hardware watchpoints available in
3871 the processor. The old ptrace interface exposes just one hardware
3872 watchpoint and no hardware breakpoints.
3874 * GDB is now able to use the Data Value Compare (DVC) register available on
3875 embedded PowerPC processors to implement in hardware simple watchpoint
3876 conditions of the form:
3878 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3880 This works in native GDB running on Linux kernels with the extended ptrace
3881 interface mentioned above.
3883 *** Changes in GDB 7.1
3887 ** Namespace Support
3889 GDB now supports importing of namespaces in C++. This enables the
3890 user to inspect variables from imported namespaces. Support for
3891 namepace aliasing has also been added. So, if a namespace is
3892 aliased in the current scope (e.g. namepace C=A; ) the user can
3893 print variables using the alias (e.g. (gdb) print C::x).
3897 All known bugs relating to the printing of virtual base class were
3898 fixed. It is now possible to call overloaded static methods using a
3903 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3904 and reinterpret_cast<> are now handled by the C++ expression parser.
3908 Xilinx MicroBlaze microblaze-*-*
3913 Xilinx MicroBlaze microblaze
3916 * Multi-program debugging.
3918 GDB now has support for multi-program (a.k.a. multi-executable or
3919 multi-exec) debugging. This allows for debugging multiple inferiors
3920 simultaneously each running a different program under the same GDB
3921 session. See "Debugging Multiple Inferiors and Programs" in the
3922 manual for more information. This implied some user visible changes
3923 in the multi-inferior support. For example, "info inferiors" now
3924 lists inferiors that are not running yet or that have exited
3925 already. See also "New commands" and "New options" below.
3927 * New tracing features
3929 GDB's tracepoint facility now includes several new features:
3931 ** Trace state variables
3933 GDB tracepoints now include support for trace state variables, which
3934 are variables managed by the target agent during a tracing
3935 experiment. They are useful for tracepoints that trigger each
3936 other, so for instance one tracepoint can count hits in a variable,
3937 and then a second tracepoint has a condition that is true when the
3938 count reaches a particular value. Trace state variables share the
3939 $-syntax of GDB convenience variables, and can appear in both
3940 tracepoint actions and condition expressions. Use the "tvariable"
3941 command to create, and "info tvariables" to view; see "Trace State
3942 Variables" in the manual for more detail.
3946 GDB now includes an option for defining fast tracepoints, which
3947 targets may implement more efficiently, such as by installing a jump
3948 into the target agent rather than a trap instruction. The resulting
3949 speedup can be by two orders of magnitude or more, although the
3950 tradeoff is that some program locations on some target architectures
3951 might not allow fast tracepoint installation, for instance if the
3952 instruction to be replaced is shorter than the jump. To request a
3953 fast tracepoint, use the "ftrace" command, with syntax identical to
3954 the regular trace command.
3956 ** Disconnected tracing
3958 It is now possible to detach GDB from the target while it is running
3959 a trace experiment, then reconnect later to see how the experiment
3960 is going. In addition, a new variable disconnected-tracing lets you
3961 tell the target agent whether to continue running a trace if the
3962 connection is lost unexpectedly.
3966 GDB now has the ability to save the trace buffer into a file, and
3967 then use that file as a target, similarly to you can do with
3968 corefiles. You can select trace frames, print data that was
3969 collected in them, and use tstatus to display the state of the
3970 tracing run at the moment that it was saved. To create a trace
3971 file, use "tsave <filename>", and to use it, do "target tfile
3974 ** Circular trace buffer
3976 You can ask the target agent to handle the trace buffer as a
3977 circular buffer, discarding the oldest trace frames to make room for
3978 newer ones, by setting circular-trace-buffer to on. This feature may
3979 not be available for all target agents.
3984 The disassemble command, when invoked with two arguments, now requires
3985 the arguments to be comma-separated.
3988 The info variables command now displays variable definitions. Files
3989 which only declare a variable are not shown.
3992 The source command is now capable of sourcing Python scripts.
3993 This feature is dependent on the debugger being build with Python
3996 Related to this enhancement is also the introduction of a new command
3997 "set script-extension" (see below).
3999 * New commands (for set/show, see "New options" below)
4001 record save [<FILENAME>]
4002 Save a file (in core file format) containing the process record
4003 execution log for replay debugging at a later time.
4005 record restore <FILENAME>
4006 Restore the process record execution log that was saved at an
4007 earlier time, for replay debugging.
4009 add-inferior [-copies <N>] [-exec <FILENAME>]
4012 clone-inferior [-copies <N>] [ID]
4013 Make a new inferior ready to execute the same program another
4014 inferior has loaded.
4019 maint info program-spaces
4020 List the program spaces loaded into GDB.
4022 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
4023 show remote interrupt-sequence
4024 Allow the user to select one of ^C, a BREAK signal or BREAK-g
4025 as the sequence to the remote target in order to interrupt the execution.
4026 Ctrl-C is a default. Some system prefers BREAK which is high level of
4027 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
4028 Magic SysRq g. It is BREAK signal and character 'g'.
4030 set remote interrupt-on-connect [on | off]
4031 show remote interrupt-on-connect
4032 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
4033 remote target when gdb connects to it. This is needed when you debug
4036 set remotebreak [on | off]
4038 Deprecated. Use "set/show remote interrupt-sequence" instead.
4040 tvariable $NAME [ = EXP ]
4041 Create or modify a trace state variable.
4044 List trace state variables and their values.
4046 delete tvariable $NAME ...
4047 Delete one or more trace state variables.
4050 Evaluate the given expressions without collecting anything into the
4051 trace buffer. (Valid in tracepoint actions only.)
4053 ftrace FN / FILE:LINE / *ADDR
4054 Define a fast tracepoint at the given function, line, or address.
4056 * New expression syntax
4058 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
4059 GDB now parses 0b101010 identically with 42.
4063 set follow-exec-mode new|same
4064 show follow-exec-mode
4065 Control whether GDB reuses the same inferior across an exec call or
4066 creates a new one. This is useful to be able to restart the old
4067 executable after the inferior having done an exec call.
4069 set default-collect EXPR, ...
4070 show default-collect
4071 Define a list of expressions to be collected at each tracepoint.
4072 This is a useful way to ensure essential items are not overlooked,
4073 such as registers or a critical global variable.
4075 set disconnected-tracing
4076 show disconnected-tracing
4077 If set to 1, the target is instructed to continue tracing if it
4078 loses its connection to GDB. If 0, the target is to stop tracing
4081 set circular-trace-buffer
4082 show circular-trace-buffer
4083 If set to on, the target is instructed to use a circular trace buffer
4084 and discard the oldest trace frames instead of stopping the trace due
4085 to a full trace buffer. If set to off, the trace stops when the buffer
4086 fills up. Some targets may not support this.
4088 set script-extension off|soft|strict
4089 show script-extension
4090 If set to "off", the debugger does not perform any script language
4091 recognition, and all sourced files are assumed to be GDB scripts.
4092 If set to "soft" (the default), files are sourced according to
4093 filename extension, falling back to GDB scripts if the first
4095 If set to "strict", files are sourced according to filename extension.
4097 set ada trust-PAD-over-XVS on|off
4098 show ada trust-PAD-over-XVS
4099 If off, activate a workaround against a bug in the debugging information
4100 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
4101 the GCC sources for more information about the GNAT encoding and
4102 PAD types in particular). It is always safe to set this option to
4103 off, but this introduces a slight performance penalty. The default
4106 * Python API Improvements
4108 ** GDB provides the new class gdb.LazyString. This is useful in
4109 some pretty-printing cases. The new method gdb.Value.lazy_string
4110 provides a simple way to create objects of this type.
4112 ** The fields returned by gdb.Type.fields now have an
4113 `is_base_class' attribute.
4115 ** The new method gdb.Type.range returns the range of an array type.
4117 ** The new method gdb.parse_and_eval can be used to parse and
4118 evaluate an expression.
4120 * New remote packets
4123 Define a trace state variable.
4126 Get the current value of a trace state variable.
4129 Set desired tracing behavior upon disconnection.
4132 Set the trace buffer to be linear or circular.
4135 Get data about the tracepoints currently in use.
4139 Process record now works correctly with hardware watchpoints.
4141 Multiple bug fixes have been made to the mips-irix port, making it
4142 much more reliable. In particular:
4143 - Debugging threaded applications is now possible again. Previously,
4144 GDB would hang while starting the program, or while waiting for
4145 the program to stop at a breakpoint.
4146 - Attaching to a running process no longer hangs.
4147 - An error occurring while loading a core file has been fixed.
4148 - Changing the value of the PC register now works again. This fixes
4149 problems observed when using the "jump" command, or when calling
4150 a function from GDB, or even when assigning a new value to $pc.
4151 - With the "finish" and "return" commands, the return value for functions
4152 returning a small array is now correctly printed.
4153 - It is now possible to break on shared library code which gets executed
4154 during a shared library init phase (code executed while executing
4155 their .init section). Previously, the breakpoint would have no effect.
4156 - GDB is now able to backtrace through the signal handler for
4157 non-threaded programs.
4159 PIE (Position Independent Executable) programs debugging is now supported.
4160 This includes debugging execution of PIC (Position Independent Code) shared
4161 libraries although for that, it should be possible to run such libraries as an
4164 *** Changes in GDB 7.0
4166 * GDB now has an interface for JIT compilation. Applications that
4167 dynamically generate code can create symbol files in memory and register
4168 them with GDB. For users, the feature should work transparently, and
4169 for JIT developers, the interface is documented in the GDB manual in the
4170 "JIT Compilation Interface" chapter.
4172 * Tracepoints may now be conditional. The syntax is as for
4173 breakpoints; either an "if" clause appended to the "trace" command,
4174 or the "condition" command is available. GDB sends the condition to
4175 the target for evaluation using the same bytecode format as is used
4176 for tracepoint actions.
4178 * The disassemble command now supports: an optional /r modifier, print the
4179 raw instructions in hex as well as in symbolic form, and an optional /m
4180 modifier to print mixed source+assembly.
4182 * Process record and replay
4184 In a architecture environment that supports ``process record and
4185 replay'', ``process record and replay'' target can record a log of
4186 the process execution, and replay it with both forward and reverse
4189 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
4190 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
4191 set execution-direction {forward|reverse}, for targets that support
4194 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
4195 feature is available with a native GDB running on kernel version
4198 * GDB now has support for multi-byte and wide character sets on the
4199 target. Strings whose character type is wchar_t, char16_t, or
4200 char32_t are now correctly printed. GDB supports wide- and unicode-
4201 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
4202 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
4203 `printf'. This feature requires iconv to work properly; if your
4204 system does not have a working iconv, GDB can use GNU libiconv. See
4205 the installation instructions for more information.
4207 * GDB now supports automatic retrieval of shared library files from
4208 remote targets. To use this feature, specify a system root that begins
4209 with the `remote:' prefix, either via the `set sysroot' command or via
4210 the `--with-sysroot' configure-time option.
4212 * "info sharedlibrary" now takes an optional regex of libraries to show,
4213 and it now reports if a shared library has no debugging information.
4215 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
4216 now complete on file names.
4218 * When completing in expressions, gdb will attempt to limit
4219 completions to allowable structure or union fields, where appropriate.
4220 For instance, consider:
4222 # struct example { int f1; double f2; };
4223 # struct example variable;
4226 If the user types TAB at the end of this command line, the available
4227 completions will be "f1" and "f2".
4229 * Inlined functions are now supported. They show up in backtraces, and
4230 the "step", "next", and "finish" commands handle them automatically.
4232 * GDB now supports the token-splicing (##) and stringification (#)
4233 operators when expanding macros. It also supports variable-arity
4236 * GDB now supports inspecting extra signal information, exported by
4237 the new $_siginfo convenience variable. The feature is currently
4238 implemented on linux ARM, i386 and amd64.
4240 * GDB can now display the VFP floating point registers and NEON vector
4241 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
4242 can provide these registers (requires Linux 2.6.30 or later). Remote
4243 and simulator targets may also provide them.
4245 * New remote packets
4248 Search memory for a sequence of bytes.
4251 Turn off `+'/`-' protocol acknowledgments to permit more efficient
4252 operation over reliable transport links. Use of this packet is
4253 controlled by the `set remote noack-packet' command.
4256 Kill the process with the specified process ID. Use this in preference
4257 to `k' when multiprocess protocol extensions are supported.
4260 Obtains additional operating system information
4264 Read or write additional signal information.
4266 * Removed remote protocol undocumented extension
4268 An undocumented extension to the remote protocol's `S' stop reply
4269 packet that permitted the stub to pass a process id was removed.
4270 Remote servers should use the `T' stop reply packet instead.
4272 * GDB now supports multiple function calling conventions according to the
4273 DWARF-2 DW_AT_calling_convention function attribute.
4275 * The SH target utilizes the aforementioned change to distinguish between gcc
4276 and Renesas calling convention. It also adds the new CLI commands
4277 `set/show sh calling-convention'.
4279 * GDB can now read compressed debug sections, as produced by GNU gold
4280 with the --compress-debug-sections=zlib flag.
4282 * 64-bit core files are now supported on AIX.
4284 * Thread switching is now supported on Tru64.
4286 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
4287 which will be allocated using malloc later in program execution.
4289 * The qXfer:libraries:read remote protocol packet now allows passing a
4290 list of section offsets.
4292 * On GNU/Linux, GDB can now attach to stopped processes. Several race
4293 conditions handling signals delivered during attach or thread creation
4294 have also been fixed.
4296 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
4297 From the user's standpoint, all unqualified instances of True and False
4298 are treated as the standard definitions, regardless of context.
4300 * GDB now parses C++ symbol and type names more flexibly. For
4303 template<typename T> class C { };
4306 GDB will now correctly handle all of:
4308 ptype C<char const *>
4309 ptype C<char const*>
4310 ptype C<const char *>
4311 ptype C<const char*>
4313 * New features in the GDB remote stub, gdbserver
4315 - The "--wrapper" command-line argument tells gdbserver to use a
4316 wrapper program to launch programs for debugging.
4318 - On PowerPC and S/390 targets, it is now possible to use a single
4319 gdbserver executable to debug both 32-bit and 64-bit programs.
4320 (This requires gdbserver itself to be built as a 64-bit executable.)
4322 - gdbserver uses the new noack protocol mode for TCP connections to
4323 reduce communications latency, if also supported and enabled in GDB.
4325 - Support for the sparc64-linux-gnu target is now included in
4328 - The amd64-linux build of gdbserver now supports debugging both
4329 32-bit and 64-bit programs.
4331 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
4332 now support hardware watchpoints, and will use them automatically
4337 GDB now has support for scripting using Python. Whether this is
4338 available is determined at configure time.
4340 New GDB commands can now be written in Python.
4342 * Ada tasking support
4344 Ada tasks can now be inspected in GDB. The following commands have
4348 Print the list of Ada tasks.
4350 Print detailed information about task number N.
4352 Print the task number of the current task.
4354 Switch the context of debugging to task number N.
4356 * Support for user-defined prefixed commands. The "define" command can
4357 add new commands to existing prefixes, e.g. "target".
4359 * Multi-inferior, multi-process debugging.
4361 GDB now has generalized support for multi-inferior debugging. See
4362 "Debugging Multiple Inferiors" in the manual for more information.
4363 Although availability still depends on target support, the command
4364 set is more uniform now. The GNU/Linux specific multi-forks support
4365 has been migrated to this new framework. This implied some user
4366 visible changes; see "New commands" and also "Removed commands"
4369 * Target descriptions can now describe the target OS ABI. See the
4370 "Target Description Format" section in the user manual for more
4373 * Target descriptions can now describe "compatible" architectures
4374 to indicate that the target can execute applications for a different
4375 architecture in addition to those for the main target architecture.
4376 See the "Target Description Format" section in the user manual for
4379 * Multi-architecture debugging.
4381 GDB now includes general supports for debugging applications on
4382 hybrid systems that use more than one single processor architecture
4383 at the same time. Each such hybrid architecture still requires
4384 specific support to be added. The only hybrid architecture supported
4385 in this version of GDB is the Cell Broadband Engine.
4387 * GDB now supports integrated debugging of Cell/B.E. applications that
4388 use both the PPU and SPU architectures. To enable support for hybrid
4389 Cell/B.E. debugging, you need to configure GDB to support both the
4390 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
4391 --enable-targets configure option.
4393 * Non-stop mode debugging.
4395 For some targets, GDB now supports an optional mode of operation in
4396 which you can examine stopped threads while other threads continue
4397 to execute freely. This is referred to as non-stop mode, with the
4398 old mode referred to as all-stop mode. See the "Non-Stop Mode"
4399 section in the user manual for more information.
4401 To be able to support remote non-stop debugging, a remote stub needs
4402 to implement the non-stop mode remote protocol extensions, as
4403 described in the "Remote Non-Stop" section of the user manual. The
4404 GDB remote stub, gdbserver, has been adjusted to support these
4405 extensions on linux targets.
4407 * New commands (for set/show, see "New options" below)
4409 catch syscall [NAME(S) | NUMBER(S)]
4410 Catch system calls. Arguments, which should be names of system
4411 calls or their numbers, mean catch only those syscalls. Without
4412 arguments, every syscall will be caught. When the inferior issues
4413 any of the specified syscalls, GDB will stop and announce the system
4414 call, both when it is called and when its call returns. This
4415 feature is currently available with a native GDB running on the
4416 Linux Kernel, under the following architectures: x86, x86_64,
4417 PowerPC and PowerPC64.
4419 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
4421 Search memory for a sequence of bytes.
4423 maint set python print-stack
4424 maint show python print-stack
4425 Show a stack trace when an error is encountered in a Python script.
4428 Invoke CODE by passing it to the Python interpreter.
4433 These allow macros to be defined, undefined, and listed
4437 Show operating system information about processes.
4440 List the inferiors currently under GDB's control.
4443 Switch focus to inferior number NUM.
4446 Detach from inferior number NUM.
4449 Kill inferior number NUM.
4453 set spu stop-on-load
4454 show spu stop-on-load
4455 Control whether to stop for new SPE threads during Cell/B.E. debugging.
4457 set spu auto-flush-cache
4458 show spu auto-flush-cache
4459 Control whether to automatically flush the software-managed cache
4460 during Cell/B.E. debugging.
4462 set sh calling-convention
4463 show sh calling-convention
4464 Control the calling convention used when calling SH target functions.
4467 show debug timestamp
4468 Control display of timestamps with GDB debugging output.
4470 set disassemble-next-line
4471 show disassemble-next-line
4472 Control display of disassembled source lines or instructions when
4475 set remote noack-packet
4476 show remote noack-packet
4477 Set/show the use of remote protocol QStartNoAckMode packet. See above
4478 under "New remote packets."
4480 set remote query-attached-packet
4481 show remote query-attached-packet
4482 Control use of remote protocol `qAttached' (query-attached) packet.
4484 set remote read-siginfo-object
4485 show remote read-siginfo-object
4486 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4489 set remote write-siginfo-object
4490 show remote write-siginfo-object
4491 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4494 set remote reverse-continue
4495 show remote reverse-continue
4496 Control use of remote protocol 'bc' (reverse-continue) packet.
4498 set remote reverse-step
4499 show remote reverse-step
4500 Control use of remote protocol 'bs' (reverse-step) packet.
4502 set displaced-stepping
4503 show displaced-stepping
4504 Control displaced stepping mode. Displaced stepping is a way to
4505 single-step over breakpoints without removing them from the debuggee.
4506 Also known as "out-of-line single-stepping".
4509 show debug displaced
4510 Control display of debugging info for displaced stepping.
4512 maint set internal-error
4513 maint show internal-error
4514 Control what GDB does when an internal error is detected.
4516 maint set internal-warning
4517 maint show internal-warning
4518 Control what GDB does when an internal warning is detected.
4523 Use a wrapper program to launch programs for debugging.
4525 set multiple-symbols (all|ask|cancel)
4526 show multiple-symbols
4527 The value of this variable can be changed to adjust the debugger behavior
4528 when an expression or a breakpoint location contains an ambiguous symbol
4529 name (an overloaded function name, for instance).
4531 set breakpoint always-inserted
4532 show breakpoint always-inserted
4533 Keep breakpoints always inserted in the target, as opposed to inserting
4534 them when resuming the target, and removing them when the target stops.
4535 This option can improve debugger performance on slow remote targets.
4537 set arm fallback-mode (arm|thumb|auto)
4538 show arm fallback-mode
4539 set arm force-mode (arm|thumb|auto)
4541 These commands control how ARM GDB determines whether instructions
4542 are ARM or Thumb. The default for both settings is auto, which uses
4543 the current CPSR value for instructions without symbols; previous
4544 versions of GDB behaved as if "set arm fallback-mode arm".
4546 set disable-randomization
4547 show disable-randomization
4548 Standalone programs run with the virtual address space randomization enabled
4549 by default on some platforms. This option keeps the addresses stable across
4550 multiple debugging sessions.
4554 Control whether other threads are stopped or not when some thread hits
4559 Requests that asynchronous execution is enabled in the target, if available.
4560 In this case, it's possible to resume target in the background, and interact
4561 with GDB while the target is running. "show target-async" displays the
4562 current state of asynchronous execution of the target.
4564 set target-wide-charset
4565 show target-wide-charset
4566 The target-wide-charset is the name of the character set that GDB
4567 uses when printing characters whose type is wchar_t.
4569 set tcp auto-retry (on|off)
4571 set tcp connect-timeout
4572 show tcp connect-timeout
4573 These commands allow GDB to retry failed TCP connections to a remote stub
4574 with a specified timeout period; this is useful if the stub is launched
4575 in parallel with GDB but may not be ready to accept connections immediately.
4577 set libthread-db-search-path
4578 show libthread-db-search-path
4579 Control list of directories which GDB will search for appropriate
4582 set schedule-multiple (on|off)
4583 show schedule-multiple
4584 Allow GDB to resume all threads of all processes or only threads of
4585 the current process.
4589 Use more aggressive caching for accesses to the stack. This improves
4590 performance of remote debugging (particularly backtraces) without
4591 affecting correctness.
4593 set interactive-mode (on|off|auto)
4594 show interactive-mode
4595 Control whether GDB runs in interactive mode (on) or not (off).
4596 When in interactive mode, GDB waits for the user to answer all
4597 queries. Otherwise, GDB does not wait and assumes the default
4598 answer. When set to auto (the default), GDB determines which
4599 mode to use based on the stdin settings.
4604 For program forks, this is replaced by the new more generic `info
4605 inferiors' command. To list checkpoints, you can still use the
4606 `info checkpoints' command, which was an alias for the `info forks'
4610 Replaced by the new `inferior' command. To switch between
4611 checkpoints, you can still use the `restart' command, which was an
4612 alias for the `fork' command.
4615 This is removed, since some targets don't have a notion of
4616 processes. To switch between processes, you can still use the
4617 `inferior' command using GDB's own inferior number.
4620 For program forks, this is replaced by the new more generic `kill
4621 inferior' command. To delete a checkpoint, you can still use the
4622 `delete checkpoint' command, which was an alias for the `delete
4626 For program forks, this is replaced by the new more generic `detach
4627 inferior' command. To detach a checkpoint, you can still use the
4628 `detach checkpoint' command, which was an alias for the `detach
4631 * New native configurations
4633 x86/x86_64 Darwin i[34567]86-*-darwin*
4635 x86_64 MinGW x86_64-*-mingw*
4639 Lattice Mico32 lm32-*
4640 x86 DICOS i[34567]86-*-dicos*
4641 x86_64 DICOS x86_64-*-dicos*
4644 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4645 (mingw32ce) debugging.
4651 These commands were actually not implemented on any target.
4653 *** Changes in GDB 6.8
4655 * New native configurations
4657 NetBSD/hppa hppa*-*netbsd*
4658 Xtensa GNU/Linux xtensa*-*-linux*
4662 NetBSD/hppa hppa*-*-netbsd*
4663 Xtensa GNU/Linux xtensa*-*-linux*
4665 * Change in command line behavior -- corefiles vs. process ids.
4667 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4668 attaching to process NUMBER fails, GDB no longer attempts to open a
4669 core file named NUMBER. Attaching to a program using the -c option
4670 is no longer supported. Instead, use the '-p' or '--pid' options.
4672 * GDB can now be built as a native debugger for debugging Windows x86
4673 (mingw32) Portable Executable (PE) programs.
4675 * Pending breakpoints no longer change their number when their address
4678 * GDB now supports breakpoints with multiple locations,
4679 including breakpoints on C++ constructors, inside C++ templates,
4680 and in inlined functions.
4682 * GDB's ability to debug optimized code has been improved. GDB more
4683 accurately identifies function bodies and lexical blocks that occupy
4684 more than one contiguous range of addresses.
4686 * Target descriptions can now describe registers for PowerPC.
4688 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4689 registers on PowerPC targets.
4691 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4692 targets even when the libthread_db library is not available.
4694 * The GDB remote stub, gdbserver, now supports the new file transfer
4695 commands (remote put, remote get, and remote delete).
4697 * The GDB remote stub, gdbserver, now supports run and attach in
4698 extended-remote mode.
4700 * hppa*64*-*-hpux11* target broken
4701 The debugger is unable to start a program and fails with the following
4702 error: "Error trying to get information about dynamic linker".
4703 The gdb-6.7 release is also affected.
4705 * GDB now supports the --enable-targets= configure option to allow
4706 building a single GDB executable that supports multiple remote
4707 target architectures.
4709 * GDB now supports debugging C and C++ programs which use the
4710 Decimal Floating Point extension. In addition, the PowerPC target
4711 now has a set of pseudo-registers to inspect decimal float values
4712 stored in two consecutive float registers.
4714 * The -break-insert MI command can optionally create pending
4717 * Improved support for debugging Ada
4718 Many improvements to the Ada language support have been made. These
4720 - Better support for Ada2005 interface types
4721 - Improved handling of arrays and slices in general
4722 - Better support for Taft-amendment types
4723 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4725 - Improved command completion in Ada
4728 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4733 set print frame-arguments (all|scalars|none)
4734 show print frame-arguments
4735 The value of this variable can be changed to control which argument
4736 values should be printed by the debugger when displaying a frame.
4741 Transfer files to and from a remote target, and delete remote files.
4748 Transfer files to and from a remote target, and delete remote files.
4750 * New remote packets
4757 Open, close, read, write, and delete files on the remote system.
4760 Attach to an existing process on the remote system, in extended-remote
4764 Run a new process on the remote system, in extended-remote mode.
4766 *** Changes in GDB 6.7
4768 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
4769 bfd, libiberty and opcodes, as revealed by static analysis donated by
4770 Coverity, Inc. (http://scan.coverity.com).
4772 * When looking up multiply-defined global symbols, GDB will now prefer the
4773 symbol definition in the current shared library if it was built using the
4774 -Bsymbolic linker option.
4776 * When the Text User Interface (TUI) is not configured, GDB will now
4777 recognize the -tui command-line option and print a message that the TUI
4780 * The GDB remote stub, gdbserver, now has lower overhead for high
4781 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
4783 * GDB for MIPS targets now autodetects whether a remote target provides
4784 32-bit or 64-bit register values.
4786 * Support for C++ member pointers has been improved.
4788 * GDB now understands XML target descriptions, which specify the
4789 target's overall architecture. GDB can read a description from
4790 a local file or over the remote serial protocol.
4792 * Vectors of single-byte data use a new integer type which is not
4793 automatically displayed as character or string data.
4795 * The /s format now works with the print command. It displays
4796 arrays of single-byte integers and pointers to single-byte integers
4799 * Target descriptions can now describe target-specific registers,
4800 for architectures which have implemented the support (currently
4801 only ARM, M68K, and MIPS).
4803 * GDB and the GDB remote stub, gdbserver, now support the XScale
4806 * The GDB remote stub, gdbserver, has been updated to support
4807 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4808 has been rewritten to use the standard GDB remote protocol.
4810 * GDB can now step into C++ functions which are called through thunks.
4812 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4814 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4815 layout. It also supports a TextSeg= and DataSeg= response when only
4816 segment base addresses (rather than offsets) are available.
4818 * The /i format now outputs any trailing branch delay slot instructions
4819 immediately following the last instruction within the count specified.
4821 * The GDB remote protocol "T" stop reply packet now supports a
4822 "library" response. Combined with the new "qXfer:libraries:read"
4823 packet, this response allows GDB to debug shared libraries on targets
4824 where the operating system manages the list of loaded libraries (e.g.
4825 Windows and SymbianOS).
4827 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4828 (DLLs) on Windows and Windows CE targets.
4830 * GDB now supports a faster verification that a .debug file matches its binary
4831 according to its build-id signature, if the signature is present.
4837 Enable or disable hardware flow control (RTS/CTS) on the serial port
4838 when debugging using remote targets.
4840 set mem inaccessible-by-default
4841 show mem inaccessible-by-default
4842 If the target supplies a memory map, for instance via the remote
4843 protocol's "qXfer:memory-map:read" packet, setting this variable
4844 prevents GDB from accessing memory outside the memory map. This
4845 is useful for targets with memory mapped registers or which react
4846 badly to accesses of unmapped address space.
4848 set breakpoint auto-hw
4849 show breakpoint auto-hw
4850 If the target supplies a memory map, for instance via the remote
4851 protocol's "qXfer:memory-map:read" packet, setting this variable
4852 lets GDB use hardware breakpoints automatically for memory regions
4853 where it can not use software breakpoints. This covers both the
4854 "break" command and internal breakpoints used for other commands
4855 including "next" and "finish".
4858 catch exception unhandled
4859 Stop the program execution when Ada exceptions are raised.
4862 Stop the program execution when an Ada assertion failed.
4866 Set an alternate system root for target files. This is a more
4867 general version of "set solib-absolute-prefix", which is now
4868 an alias to "set sysroot".
4871 Provide extended SPU facility status information. This set of
4872 commands is available only when debugging the Cell/B.E. SPU
4875 * New native configurations
4877 OpenBSD/sh sh*-*openbsd*
4880 unset tdesc filename
4882 Use the specified local file as an XML target description, and do
4883 not query the target for its built-in description.
4887 OpenBSD/sh sh*-*-openbsd*
4888 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4889 Toshiba Media Processor mep-elf
4891 * New remote packets
4894 Ignore the specified signals; pass them directly to the debugged program
4895 without stopping other threads or reporting them to GDB.
4897 qXfer:features:read:
4898 Read an XML target description from the target, which describes its
4903 Read or write contents of an spufs file on the target system. These
4904 packets are available only on the Cell/B.E. SPU architecture.
4906 qXfer:libraries:read:
4907 Report the loaded shared libraries. Combined with new "T" packet
4908 response, this packet allows GDB to debug shared libraries on
4909 targets where the operating system manages the list of loaded
4910 libraries (e.g. Windows and SymbianOS).
4914 Support for these obsolete configurations has been removed.
4922 i[34567]86-*-lynxos*
4923 i[34567]86-*-netware*
4924 i[34567]86-*-sco3.2v5*
4925 i[34567]86-*-sco3.2v4*
4927 i[34567]86-*-sysv4.2*
4930 i[34567]86-*-unixware2*
4931 i[34567]86-*-unixware*
4940 * Other removed features
4947 Various m68k-only ROM monitors.
4954 Various Renesas ROM monitors and debugging interfaces for SH and
4959 Support for a Macraigor serial interface to on-chip debugging.
4960 GDB does not directly support the newer parallel or USB
4965 A debug information format. The predecessor to DWARF 2 and
4966 DWARF 3, which are still supported.
4968 Support for the HP aCC compiler on HP-UX/PA-RISC
4970 SOM-encapsulated symbolic debugging information, automatic
4971 invocation of pxdb, and the aCC custom C++ ABI. This does not
4972 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4973 with aCC can still be debugged on an assembly level.
4975 MIPS ".pdr" sections
4977 A MIPS-specific format used to describe stack frame layout
4978 in debugging information.
4982 GDB could work with an older version of Guile to debug
4983 the interpreter and Scheme programs running in it.
4985 set mips stack-arg-size
4986 set mips saved-gpreg-size
4988 Use "set mips abi" to control parameter passing for MIPS.
4990 *** Changes in GDB 6.6
4995 Cell Broadband Engine SPU spu-elf
4997 * GDB can now be configured as a cross-debugger targeting native Windows
4998 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4999 running on a Windows system over TCP/IP to debug Windows programs.
5001 * The GDB remote stub, gdbserver, has been updated to support Windows and
5002 Cygwin debugging. Both single-threaded and multi-threaded programs are
5005 * The "set trust-readonly-sections" command works again. This command was
5006 broken in GDB 6.3, 6.4, and 6.5.
5008 * The "load" command now supports writing to flash memory, if the remote
5009 stub provides the required support.
5011 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
5012 longer requires symbolic debug information (e.g. DWARF-2).
5017 unset substitute-path
5018 show substitute-path
5019 Manage a list of substitution rules that GDB uses to rewrite the name
5020 of the directories where the sources are located. This can be useful
5021 for instance when the sources were moved to a different location
5022 between compilation and debugging.
5026 Print each CLI command as it is executed. Each command is prefixed with
5027 a number of `+' symbols representing the nesting depth.
5028 The source command now has a `-v' option to enable the same feature.
5032 The ARM Demon monitor support (RDP protocol, "target rdp").
5034 Kernel Object Display, an embedded debugging feature which only worked with
5035 an obsolete version of Cisco IOS.
5037 The 'set download-write-size' and 'show download-write-size' commands.
5039 * New remote packets
5042 Tell a stub about GDB client features, and request remote target features.
5043 The first feature implemented is PacketSize, which allows the target to
5044 specify the size of packets it can handle - to minimize the number of
5045 packets required and improve performance when connected to a remote
5049 Fetch an OS auxilliary vector from the remote stub. This packet is a
5050 more efficient replacement for qPart:auxv:read.
5052 qXfer:memory-map:read:
5053 Fetch a memory map from the remote stub, including information about
5054 RAM, ROM, and flash memory devices.
5059 Erase and program a flash memory device.
5061 * Removed remote packets
5064 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
5065 used it, and only gdbserver implemented it.
5067 *** Changes in GDB 6.5
5071 Renesas M32C/M16C m32c-elf
5073 Morpho Technologies ms1 ms1-elf
5077 init-if-undefined Initialize a convenience variable, but
5078 only if it doesn't already have a value.
5080 The following commands are presently only implemented for native GNU/Linux:
5082 checkpoint Save a snapshot of the program state.
5084 restart <n> Return the program state to a
5085 previously saved state.
5087 info checkpoints List currently saved checkpoints.
5089 delete-checkpoint <n> Delete a previously saved checkpoint.
5091 set|show detach-on-fork Tell gdb whether to detach from a newly
5092 forked process, or to keep debugging it.
5094 info forks List forks of the user program that
5095 are available to be debugged.
5097 fork <n> Switch to debugging one of several
5098 forks of the user program that are
5099 available to be debugged.
5101 delete-fork <n> Delete a fork from the list of forks
5102 that are available to be debugged (and
5103 kill the forked process).
5105 detach-fork <n> Delete a fork from the list of forks
5106 that are available to be debugged (and
5107 allow the process to continue).
5111 Morpho Technologies ms2 ms1-elf
5113 * Improved Windows host support
5115 GDB now builds as a cross debugger hosted on i686-mingw32, including
5116 native console support, and remote communications using either
5117 network sockets or serial ports.
5119 * Improved Modula-2 language support
5121 GDB can now print most types in the Modula-2 syntax. This includes:
5122 basic types, set types, record types, enumerated types, range types,
5123 pointer types and ARRAY types. Procedure var parameters are correctly
5124 printed and hexadecimal addresses and character constants are also
5125 written in the Modula-2 syntax. Best results can be obtained by using
5126 GNU Modula-2 together with the -gdwarf-2 command line option.
5130 The ARM rdi-share module.
5132 The Netware NLM debug server.
5134 *** Changes in GDB 6.4
5136 * New native configurations
5138 OpenBSD/arm arm*-*-openbsd*
5139 OpenBSD/mips64 mips64-*-openbsd*
5143 Morpho Technologies ms1 ms1-elf
5145 * New command line options
5147 --batch-silent As for --batch, but totally silent.
5148 --return-child-result The debugger will exist with the same value
5149 the child (debugged) program exited with.
5150 --eval-command COMMAND, -ex COMMAND
5151 Execute a single GDB CLI command. This may be
5152 specified multiple times and in conjunction
5153 with the --command (-x) option.
5155 * Deprecated commands removed
5157 The following commands, that were deprecated in 2000, have been
5161 set|show arm disassembly-flavor set|show arm disassembler
5162 othernames set arm disassembler
5163 set|show remotedebug set|show debug remote
5164 set|show archdebug set|show debug arch
5165 set|show eventdebug set|show debug event
5168 * New BSD user-level threads support
5170 It is now possible to debug programs using the user-level threads
5171 library on OpenBSD and FreeBSD. Currently supported (target)
5174 FreeBSD/amd64 x86_64-*-freebsd*
5175 FreeBSD/i386 i386-*-freebsd*
5176 OpenBSD/i386 i386-*-openbsd*
5178 Note that the new kernel threads libraries introduced in FreeBSD 5.x
5179 are not yet supported.
5181 * New support for Matsushita MN10300 w/sim added
5182 (Work in progress). mn10300-elf.
5184 * REMOVED configurations and files
5186 VxWorks and the XDR protocol *-*-vxworks
5187 Motorola MCORE mcore-*-*
5188 National Semiconductor NS32000 ns32k-*-*
5190 * New "set print array-indexes" command
5192 After turning this setting "on", GDB prints the index of each element
5193 when displaying arrays. The default is "off" to preserve the previous
5196 * VAX floating point support
5198 GDB now supports the not-quite-ieee VAX F and D floating point formats.
5200 * User-defined command support
5202 In addition to using $arg0..$arg9 for argument passing, it is now possible
5203 to use $argc to determine now many arguments have been passed. See the
5204 section on user-defined commands in the user manual for more information.
5206 *** Changes in GDB 6.3:
5208 * New command line option
5210 GDB now accepts -l followed by a number to set the timeout for remote
5213 * GDB works with GCC -feliminate-dwarf2-dups
5215 GDB now supports a more compact representation of DWARF-2 debug
5216 information using DW_FORM_ref_addr references. These are produced
5217 by GCC with the option -feliminate-dwarf2-dups and also by some
5218 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
5219 to use -feliminate-dwarf2-dups.
5221 * Internationalization
5223 When supported by the host system, GDB will be built with
5224 internationalization (libintl). The task of marking up the sources is
5225 continued, we're looking forward to our first translation.
5229 Initial support for debugging programs compiled with the GNAT
5230 implementation of the Ada programming language has been integrated
5231 into GDB. In this release, support is limited to expression evaluation.
5233 * New native configurations
5235 GNU/Linux/m32r m32r-*-linux-gnu
5239 GDB's remote protocol now includes support for the 'p' packet. This
5240 packet is used to fetch individual registers from a remote inferior.
5242 * END-OF-LIFE registers[] compatibility module
5244 GDB's internal register infrastructure has been completely rewritten.
5245 The new infrastructure making possible the implementation of key new
5246 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
5249 GDB 6.3 will be the last release to include the registers[]
5250 compatibility module that allowed out-of-date configurations to
5251 continue to work. This change directly impacts the following
5261 powerpc bdm protocol
5263 Unless there is activity to revive these configurations, they will be
5264 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
5266 * OBSOLETE configurations and files
5268 Configurations that have been declared obsolete in this release have
5269 been commented out. Unless there is activity to revive these
5270 configurations, the next release of GDB will have their sources
5271 permanently REMOVED.
5280 *** Changes in GDB 6.2.1:
5282 * MIPS `break main; run' gave an heuristic-fence-post warning
5284 When attempting to run even a simple program, a warning about
5285 heuristic-fence-post being hit would be reported. This problem has
5288 * MIPS IRIX 'long double' crashed GDB
5290 When examining a long double variable, GDB would get a segmentation
5291 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
5292 IRIX long double values).
5296 A bug in the VAX stack code was causing problems with the "next"
5297 command. This problem has been fixed.
5299 *** Changes in GDB 6.2:
5301 * Fix for ``many threads''
5303 On GNU/Linux systems that use the NPTL threads library, a program
5304 rapidly creating and deleting threads would confuse GDB leading to the
5307 ptrace: No such process.
5308 thread_db_get_info: cannot get thread info: generic error
5310 This problem has been fixed.
5312 * "-async" and "-noasync" options removed.
5314 Support for the broken "-noasync" option has been removed (it caused
5317 * New ``start'' command.
5319 This command runs the program until the beginning of the main procedure.
5321 * New BSD Kernel Data Access Library (libkvm) interface
5323 Using ``target kvm'' it is now possible to debug kernel core dumps and
5324 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
5325 platforms. Currently supported (native-only) configurations are:
5327 FreeBSD/amd64 x86_64-*-freebsd*
5328 FreeBSD/i386 i?86-*-freebsd*
5329 NetBSD/i386 i?86-*-netbsd*
5330 NetBSD/m68k m68*-*-netbsd*
5331 NetBSD/sparc sparc-*-netbsd*
5332 OpenBSD/amd64 x86_64-*-openbsd*
5333 OpenBSD/i386 i?86-*-openbsd*
5334 OpenBSD/m68k m68*-openbsd*
5335 OpenBSD/sparc sparc-*-openbsd*
5337 * Signal trampoline code overhauled
5339 Many generic problems with GDB's signal handling code have been fixed.
5340 These include: backtraces through non-contiguous stacks; recognition
5341 of sa_sigaction signal trampolines; backtrace from a NULL pointer
5342 call; backtrace through a signal trampoline; step into and out of
5343 signal handlers; and single-stepping in the signal trampoline.
5345 Please note that kernel bugs are a limiting factor here. These
5346 features have been shown to work on an s390 GNU/Linux system that
5347 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
5349 * Cygwin support for DWARF 2 added.
5351 * New native configurations
5353 GNU/Linux/hppa hppa*-*-linux*
5354 OpenBSD/hppa hppa*-*-openbsd*
5355 OpenBSD/m68k m68*-*-openbsd*
5356 OpenBSD/m88k m88*-*-openbsd*
5357 OpenBSD/powerpc powerpc-*-openbsd*
5358 NetBSD/vax vax-*-netbsd*
5359 OpenBSD/vax vax-*-openbsd*
5361 * END-OF-LIFE frame compatibility module
5363 GDB's internal frame infrastructure has been completely rewritten.
5364 The new infrastructure making it possible to support key new features
5365 including DWARF 2 Call Frame Information. To aid in the task of
5366 migrating old configurations to this new infrastructure, a
5367 compatibility module, that allowed old configurations to continue to
5368 work, was also included.
5370 GDB 6.2 will be the last release to include this frame compatibility
5371 module. This change directly impacts the following configurations:
5381 Unless there is activity to revive these configurations, they will be
5382 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
5384 * REMOVED configurations and files
5386 Sun 3, running SunOS 3 m68*-*-sunos3*
5387 Sun 3, running SunOS 4 m68*-*-sunos4*
5388 Sun 2, running SunOS 3 m68000-*-sunos3*
5389 Sun 2, running SunOS 4 m68000-*-sunos4*
5390 Motorola 680x0 running LynxOS m68*-*-lynxos*
5391 AT&T 3b1/Unix pc m68*-att-*
5392 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5393 decstation mips-dec-* mips-little-*
5394 riscos mips-*-riscos* mips-*-sysv*
5395 sonymips mips-sony-*
5396 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5398 *** Changes in GDB 6.1.1:
5400 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
5402 The TUI (Text-mode User Interface) is now built as part of a default
5403 GDB configuration. It is enabled by either selecting the TUI with the
5404 command line option "-i=tui" or by running the separate "gdbtui"
5405 program. For more information on the TUI, see the manual "Debugging
5408 * Pending breakpoint support (also included in GDB 6.1)
5410 Support has been added to allow you to specify breakpoints in shared
5411 libraries that have not yet been loaded. If a breakpoint location
5412 cannot be found, and the "breakpoint pending" option is set to auto,
5413 GDB queries you if you wish to make the breakpoint pending on a future
5414 shared-library load. If and when GDB resolves the breakpoint symbol,
5415 the pending breakpoint is removed as one or more regular breakpoints
5418 Pending breakpoints are very useful for GCJ Java debugging.
5420 * Fixed ISO-C build problems
5422 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
5423 non ISO-C code that stopped them being built using a more strict ISO-C
5424 compiler (e.g., IBM's C compiler).
5426 * Fixed build problem on IRIX 5
5428 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
5429 wasn't able to compile compile on an IRIX 5 system.
5431 * Added execute permission to gdb/gdbserver/configure
5433 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
5434 permission. This bug would cause configure to fail on a number of
5435 systems (Solaris, IRIX). Ref: server/519.
5437 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
5439 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
5440 has been updated to use constant array sizes.
5442 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
5444 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
5445 its generated DWARF Call Frame Info. This encoding was causing GDB to
5446 panic, that panic has been fixed. Ref: gdb/1628.
5448 * Fixed a problem when examining parameters in shared library code.
5450 When examining parameters in optimized shared library code generated
5451 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
5452 not available''. GDB now correctly displays the variable's value.
5454 *** Changes in GDB 6.1:
5456 * Removed --with-mmalloc
5458 Support for the mmalloc memory manager has been removed, as it
5459 conflicted with the internal gdb byte cache.
5461 * Changes in AMD64 configurations
5463 The AMD64 target now includes the %cs and %ss registers. As a result
5464 the AMD64 remote protocol has changed; this affects the floating-point
5465 and SSE registers. If you rely on those registers for your debugging,
5466 you should upgrade gdbserver on the remote side.
5468 * Revised SPARC target
5470 The SPARC target has been completely revised, incorporating the
5471 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
5472 support for LynxOS and SunOS 4 has been dropped. Calling functions
5473 from within GDB on operating systems with a non-executable stack
5474 (Solaris, OpenBSD) now works.
5478 GDB has a new C++ demangler which does a better job on the mangled
5479 names generated by current versions of g++. It also runs faster, so
5480 with this and other changes gdb should now start faster on large C++
5483 * DWARF 2 Location Expressions
5485 GDB support for location expressions has been extended to support function
5486 arguments and frame bases. Older versions of GDB could crash when they
5489 * C++ nested types and namespaces
5491 GDB's support for nested types and namespaces in C++ has been
5492 improved, especially if you use the DWARF 2 debugging format. (This
5493 is the default for recent versions of GCC on most platforms.)
5494 Specifically, if you have a class "Inner" defined within a class or
5495 namespace "Outer", then GDB realizes that the class's name is
5496 "Outer::Inner", not simply "Inner". This should greatly reduce the
5497 frequency of complaints about not finding RTTI symbols. In addition,
5498 if you are stopped at inside of a function defined within a namespace,
5499 GDB modifies its name lookup accordingly.
5501 * New native configurations
5503 NetBSD/amd64 x86_64-*-netbsd*
5504 OpenBSD/amd64 x86_64-*-openbsd*
5505 OpenBSD/alpha alpha*-*-openbsd*
5506 OpenBSD/sparc sparc-*-openbsd*
5507 OpenBSD/sparc64 sparc64-*-openbsd*
5509 * New debugging protocols
5511 M32R with SDI protocol m32r-*-elf*
5513 * "set prompt-escape-char" command deleted.
5515 The command "set prompt-escape-char" has been deleted. This command,
5516 and its very obscure effect on GDB's prompt, was never documented,
5517 tested, nor mentioned in the NEWS file.
5519 * OBSOLETE configurations and files
5521 Configurations that have been declared obsolete in this release have
5522 been commented out. Unless there is activity to revive these
5523 configurations, the next release of GDB will have their sources
5524 permanently REMOVED.
5526 Sun 3, running SunOS 3 m68*-*-sunos3*
5527 Sun 3, running SunOS 4 m68*-*-sunos4*
5528 Sun 2, running SunOS 3 m68000-*-sunos3*
5529 Sun 2, running SunOS 4 m68000-*-sunos4*
5530 Motorola 680x0 running LynxOS m68*-*-lynxos*
5531 AT&T 3b1/Unix pc m68*-att-*
5532 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5533 decstation mips-dec-* mips-little-*
5534 riscos mips-*-riscos* mips-*-sysv*
5535 sonymips mips-sony-*
5536 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5538 * REMOVED configurations and files
5540 SGI Irix-4.x mips-sgi-irix4 or iris4
5541 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5542 Z8000 simulator z8k-zilog-none or z8ksim
5543 Matsushita MN10200 w/simulator mn10200-*-*
5544 H8/500 simulator h8500-hitachi-hms or h8500hms
5545 HP/PA running BSD hppa*-*-bsd*
5546 HP/PA running OSF/1 hppa*-*-osf*
5547 HP/PA Pro target hppa*-*-pro*
5548 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5549 386BSD i[3456]86-*-bsd*
5550 Sequent family i[3456]86-sequent-sysv4*
5551 i[3456]86-sequent-sysv*
5552 i[3456]86-sequent-bsd*
5553 SPARC running LynxOS sparc-*-lynxos*
5554 SPARC running SunOS 4 sparc-*-sunos4*
5555 Tsqware Sparclet sparclet-*-*
5556 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5558 *** Changes in GDB 6.0:
5562 Support for debugging the Objective-C programming language has been
5563 integrated into GDB.
5565 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5567 DWARF 2's Call Frame Information makes available compiler generated
5568 information that more exactly describes the program's run-time stack.
5569 By using this information, GDB is able to provide more robust stack
5572 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5573 have been updated to use a new backtrace mechanism which includes
5574 DWARF 2 CFI support.
5578 GDB's remote protocol has been extended to include support for hosted
5579 file I/O (where the remote target uses GDB's file system). See GDB's
5580 remote protocol documentation for details.
5582 * All targets using the new architecture framework.
5584 All of GDB's targets have been updated to use the new internal
5585 architecture framework. The way is now open for future GDB releases
5586 to include cross-architecture native debugging support (i386 on amd64,
5589 * GNU/Linux's Thread Local Storage (TLS)
5591 GDB now includes support for for the GNU/Linux implementation of
5592 per-thread variables.
5594 * GNU/Linux's Native POSIX Thread Library (NPTL)
5596 GDB's thread code has been updated to work with either the new
5597 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5599 * Separate debug info.
5601 GDB, in conjunction with BINUTILS, now supports a mechanism for
5602 automatically loading debug information from a separate file. Instead
5603 of shipping full debug and non-debug versions of system libraries,
5604 system integrators can now instead ship just the stripped libraries
5605 and optional debug files.
5607 * DWARF 2 Location Expressions
5609 DWARF 2 Location Expressions allow the compiler to more completely
5610 describe the location of variables (even in optimized code) to the
5613 GDB now includes preliminary support for location expressions (support
5614 for DW_OP_piece is still missing).
5618 A number of long standing bugs that caused GDB to die while starting a
5619 Java application have been fixed. GDB's Java support is now
5620 considered "useable".
5622 * GNU/Linux support for fork, vfork, and exec.
5624 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5625 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5628 * GDB supports logging output to a file
5630 There are two new commands, "set logging" and "show logging", which can be
5631 used to capture GDB's output to a file.
5633 * The meaning of "detach" has changed for gdbserver
5635 The "detach" command will now resume the application, as documented. To
5636 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5639 * d10v, m68hc11 `regs' command deprecated
5641 The `info registers' command has been updated so that it displays the
5642 registers using a format identical to the old `regs' command.
5646 A new command, "maint set profile on/off", has been added. This command can
5647 be used to enable or disable profiling while running GDB, to profile a
5648 session or a set of commands. In addition there is a new configure switch,
5649 "--enable-profiling", which will cause GDB to be compiled with profiling
5650 data, for more informative profiling results.
5652 * Default MI syntax changed to "mi2".
5654 The default MI (machine interface) syntax, enabled by the command line
5655 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5656 "mi1", can be enabled by specifying the option "-i=mi1".
5658 Support for the original "mi0" syntax (included in GDB 5.0) has been
5661 Fix for gdb/192: removed extraneous space when displaying frame level.
5662 Fix for gdb/672: update changelist is now output in mi list format.
5663 Fix for gdb/702: a -var-assign that updates the value now shows up
5664 in a subsequent -var-update.
5666 * New native configurations.
5668 FreeBSD/amd64 x86_64-*-freebsd*
5670 * Multi-arched targets.
5672 HP/PA HPUX11 hppa*-*-hpux*
5673 Renesas M32R/D w/simulator m32r-*-elf*
5675 * OBSOLETE configurations and files
5677 Configurations that have been declared obsolete in this release have
5678 been commented out. Unless there is activity to revive these
5679 configurations, the next release of GDB will have their sources
5680 permanently REMOVED.
5682 Z8000 simulator z8k-zilog-none or z8ksim
5683 Matsushita MN10200 w/simulator mn10200-*-*
5684 H8/500 simulator h8500-hitachi-hms or h8500hms
5685 HP/PA running BSD hppa*-*-bsd*
5686 HP/PA running OSF/1 hppa*-*-osf*
5687 HP/PA Pro target hppa*-*-pro*
5688 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5689 Sequent family i[3456]86-sequent-sysv4*
5690 i[3456]86-sequent-sysv*
5691 i[3456]86-sequent-bsd*
5692 Tsqware Sparclet sparclet-*-*
5693 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5695 * REMOVED configurations and files
5698 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5699 IBM AIX PS/2 i[3456]86-*-aix
5700 i386 running Mach 3.0 i[3456]86-*-mach3*
5701 i386 running Mach i[3456]86-*-mach*
5702 i386 running OSF/1 i[3456]86-*osf1mk*
5703 HP/Apollo 68k Family m68*-apollo*-sysv*,
5705 m68*-hp-bsd*, m68*-hp-hpux*
5706 Argonaut Risc Chip (ARC) arc-*-*
5707 Mitsubishi D30V d30v-*-*
5708 Fujitsu FR30 fr30-*-elf*
5709 OS/9000 i[34]86-*-os9k
5710 I960 with MON960 i960-*-coff
5712 * MIPS $fp behavior changed
5714 The convenience variable $fp, for the MIPS, now consistently returns
5715 the address of the current frame's base. Previously, depending on the
5716 context, $fp could refer to either $sp or the current frame's base
5717 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5718 The GNU Source-Level Debugger''.
5720 *** Changes in GDB 5.3:
5722 * GNU/Linux shared library multi-threaded performance improved.
5724 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5725 `/proc', in preference to `ptrace' for memory reads. This may result
5726 in an improvement in the start-up time of multi-threaded, shared
5727 library applications when run under GDB. One GDB user writes: ``loads
5728 shared libs like mad''.
5730 * ``gdbserver'' now supports multi-threaded applications on some targets
5732 Support for debugging multi-threaded applications which use
5733 the GNU/Linux LinuxThreads package has been added for
5734 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5735 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5737 * GDB now supports C/C++ preprocessor macros.
5739 GDB now expands preprocessor macro invocations in C/C++ expressions,
5740 and provides various commands for showing macro definitions and how
5743 The new command `macro expand EXPRESSION' expands any macro
5744 invocations in expression, and shows the result.
5746 The new command `show macro MACRO-NAME' shows the definition of the
5747 macro named MACRO-NAME, and where it was defined.
5749 Most compilers don't include information about macros in the debugging
5750 information by default. In GCC 3.1, for example, you need to compile
5751 your program with the options `-gdwarf-2 -g3'. If the macro
5752 information is present in the executable, GDB will read it.
5754 * Multi-arched targets.
5756 DEC Alpha (partial) alpha*-*-*
5757 DEC VAX (partial) vax-*-*
5759 National Semiconductor NS32000 (partial) ns32k-*-*
5760 Motorola 68000 (partial) m68k-*-*
5761 Motorola MCORE mcore-*-*
5765 Fujitsu FRV architecture added by Red Hat frv*-*-*
5768 * New native configurations
5770 Alpha NetBSD alpha*-*-netbsd*
5771 SH NetBSD sh*-*-netbsdelf*
5772 MIPS NetBSD mips*-*-netbsd*
5773 UltraSPARC NetBSD sparc64-*-netbsd*
5775 * OBSOLETE configurations and files
5777 Configurations that have been declared obsolete in this release have
5778 been commented out. Unless there is activity to revive these
5779 configurations, the next release of GDB will have their sources
5780 permanently REMOVED.
5782 Mitsubishi D30V d30v-*-*
5783 OS/9000 i[34]86-*-os9k
5784 IBM AIX PS/2 i[3456]86-*-aix
5785 Fujitsu FR30 fr30-*-elf*
5786 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5787 Argonaut Risc Chip (ARC) arc-*-*
5788 i386 running Mach 3.0 i[3456]86-*-mach3*
5789 i386 running Mach i[3456]86-*-mach*
5790 i386 running OSF/1 i[3456]86-*osf1mk*
5791 HP/Apollo 68k Family m68*-apollo*-sysv*,
5793 m68*-hp-bsd*, m68*-hp-hpux*
5794 I960 with MON960 i960-*-coff
5796 * OBSOLETE languages
5798 CHILL, a Pascal like language used by telecommunications companies.
5800 * REMOVED configurations and files
5802 AMD 29k family via UDI a29k-amd-udi, udi29k
5803 A29K VxWorks a29k-*-vxworks
5804 AMD 29000 embedded, using EBMON a29k-none-none
5805 AMD 29000 embedded with COFF a29k-none-coff
5806 AMD 29000 embedded with a.out a29k-none-aout
5808 testsuite/gdb.hp/gdb.threads-hp/ directory
5810 * New command "set max-user-call-depth <nnn>"
5812 This command allows the user to limit the call depth of user-defined
5813 commands. The default is 1024.
5815 * Changes in FreeBSD/i386 native debugging.
5817 Support for the "generate-core-file" has been added.
5819 * New commands "dump", "append", and "restore".
5821 These commands allow data to be copied from target memory
5822 to a bfd-format or binary file (dump and append), and back
5823 from a file into memory (restore).
5825 * Improved "next/step" support on multi-processor Alpha Tru64.
5827 The previous single-step mechanism could cause unpredictable problems,
5828 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5829 of a software single-step mechanism prevents this.
5831 *** Changes in GDB 5.2.1:
5839 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5840 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5841 Fix, by Joel Brobecker imported from mainline.
5843 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5844 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5845 Fix, by Fred Fish, imported from mainline.
5847 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5848 Surprisingly enough, it works now.
5849 By Michal Ludvig, imported from mainline.
5851 i386 hardware watchpoint support:
5852 avoid misses on second run for some targets.
5853 By Pierre Muller, imported from mainline.
5855 *** Changes in GDB 5.2:
5857 * New command "set trust-readonly-sections on[off]".
5859 This command is a hint that tells gdb that read-only sections
5860 really are read-only (ie. that their contents will not change).
5861 In this mode, gdb will go to the object file rather than the
5862 target to read memory from read-only sections (such as ".text").
5863 This can be a significant performance improvement on some
5864 (notably embedded) targets.
5866 * New command "generate-core-file" (or "gcore").
5868 This new gdb command allows the user to drop a core file of the child
5869 process state at any time. So far it's been implemented only for
5870 GNU/Linux and Solaris, but should be relatively easily ported to other
5871 hosts. Argument is core file name (defaults to core.<pid>).
5873 * New command line option
5875 GDB now accepts --pid or -p followed by a process id.
5877 * Change in command line behavior -- corefiles vs. process ids.
5879 There is a subtle behavior in the way in which GDB handles
5880 command line arguments. The first non-flag argument is always
5881 a program to debug, but the second non-flag argument may either
5882 be a corefile or a process id. Previously, GDB would attempt to
5883 open the second argument as a corefile, and if that failed, would
5884 issue a superfluous error message and then attempt to attach it as
5885 a process. Now, if the second argument begins with a non-digit,
5886 it will be treated as a corefile. If it begins with a digit,
5887 GDB will attempt to attach it as a process, and if no such process
5888 is found, will then attempt to open it as a corefile.
5890 * Changes in ARM configurations.
5892 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5893 configuration is fully multi-arch.
5895 * New native configurations
5897 ARM NetBSD arm*-*-netbsd*
5898 x86 OpenBSD i[3456]86-*-openbsd*
5899 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5900 Sparc64 running FreeBSD sparc64-*-freebsd*
5904 Sanyo XStormy16 xstormy16-elf
5906 * OBSOLETE configurations and files
5908 Configurations that have been declared obsolete in this release have
5909 been commented out. Unless there is activity to revive these
5910 configurations, the next release of GDB will have their sources
5911 permanently REMOVED.
5913 AMD 29k family via UDI a29k-amd-udi, udi29k
5914 A29K VxWorks a29k-*-vxworks
5915 AMD 29000 embedded, using EBMON a29k-none-none
5916 AMD 29000 embedded with COFF a29k-none-coff
5917 AMD 29000 embedded with a.out a29k-none-aout
5919 testsuite/gdb.hp/gdb.threads-hp/ directory
5921 * REMOVED configurations and files
5923 TI TMS320C80 tic80-*-*
5925 PowerPC Solaris powerpcle-*-solaris*
5926 PowerPC Windows NT powerpcle-*-cygwin32
5927 PowerPC Netware powerpc-*-netware*
5928 Harris/CXUX m88k m88*-harris-cxux*
5929 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5930 ns32k-utek-sysv* ns32k-utek-*
5931 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5932 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5933 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5934 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5935 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5937 * Changes to command line processing
5939 The new `--args' feature can be used to specify command-line arguments
5940 for the inferior from gdb's command line.
5942 * Changes to key bindings
5944 There is a new `operate-and-get-next' function bound to `C-o'.
5946 *** Changes in GDB 5.1.1
5948 Fix compile problem on DJGPP.
5950 Fix a problem with floating-point registers on the i386 being
5953 Fix to stop GDB crashing on .debug_str debug info.
5955 Numerous documentation fixes.
5957 Numerous testsuite fixes.
5959 *** Changes in GDB 5.1:
5961 * New native configurations
5963 Alpha FreeBSD alpha*-*-freebsd*
5964 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5965 MIPS GNU/Linux mips*-*-linux*
5966 MIPS SGI Irix 6.x mips*-sgi-irix6*
5967 ia64 AIX ia64-*-aix*
5968 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5972 Motorola 68HC11 and 68HC12 m68hc11-elf
5974 UltraSparc running GNU/Linux sparc64-*-linux*
5976 * OBSOLETE configurations and files
5978 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5979 Harris/CXUX m88k m88*-harris-cxux*
5980 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5981 ns32k-utek-sysv* ns32k-utek-*
5982 TI TMS320C80 tic80-*-*
5984 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5985 PowerPC Solaris powerpcle-*-solaris*
5986 PowerPC Windows NT powerpcle-*-cygwin32
5987 PowerPC Netware powerpc-*-netware*
5988 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5989 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5990 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5991 Apple Macintosh (MPW) host N/A
5993 stuff.c (Program to stuff files into a specially prepared space in kdb)
5994 kdb-start.c (Main loop for the standalone kernel debugger)
5996 Configurations that have been declared obsolete in this release have
5997 been commented out. Unless there is activity to revive these
5998 configurations, the next release of GDB will have their sources
5999 permanently REMOVED.
6001 * REMOVED configurations and files
6003 Altos 3068 m68*-altos-*
6004 Convex c1-*-*, c2-*-*
6006 ARM RISCix arm-*-* (as host)
6010 * GDB has been converted to ISO C.
6012 GDB's source code has been converted to ISO C. In particular, the
6013 sources are fully protoized, and rely on standard headers being
6018 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
6020 * The MI enabled by default.
6022 The new machine oriented interface (MI) introduced in GDB 5.0 has been
6023 revised and enabled by default. Packages which use GDB as a debugging
6024 engine behind a UI or another front end are encouraged to switch to
6025 using the GDB/MI interface, instead of the old annotations interface
6026 which is now deprecated.
6028 * Support for debugging Pascal programs.
6030 GDB now includes support for debugging Pascal programs. The following
6031 main features are supported:
6033 - Pascal-specific data types such as sets;
6035 - automatic recognition of Pascal sources based on file-name
6038 - Pascal-style display of data types, variables, and functions;
6040 - a Pascal expression parser.
6042 However, some important features are not yet supported.
6044 - Pascal string operations are not supported at all;
6046 - there are some problems with boolean types;
6048 - Pascal type hexadecimal constants are not supported
6049 because they conflict with the internal variables format;
6051 - support for Pascal objects and classes is not full yet;
6053 - unlike Pascal, GDB is case-sensitive for symbol names.
6055 * Changes in completion.
6057 Commands such as `shell', `run' and `set args', which pass arguments
6058 to inferior programs, now complete on file names, similar to what
6059 users expect at the shell prompt.
6061 Commands which accept locations, such as `disassemble', `print',
6062 `breakpoint', `until', etc. now complete on filenames as well as
6063 program symbols. Thus, if you type "break foob TAB", and the source
6064 files linked into the programs include `foobar.c', that file name will
6065 be one of the candidates for completion. However, file names are not
6066 considered for completion after you typed a colon that delimits a file
6067 name from a name of a function in that file, as in "break foo.c:bar".
6069 `set demangle-style' completes on available demangling styles.
6071 * New platform-independent commands:
6073 It is now possible to define a post-hook for a command as well as a
6074 hook that runs before the command. For more details, see the
6075 documentation of `hookpost' in the GDB manual.
6077 * Changes in GNU/Linux native debugging.
6079 Support for debugging multi-threaded programs has been completely
6080 revised for all platforms except m68k and sparc. You can now debug as
6081 many threads as your system allows you to have.
6083 Attach/detach is supported for multi-threaded programs.
6085 Support for SSE registers was added for x86. This doesn't work for
6086 multi-threaded programs though.
6088 * Changes in MIPS configurations.
6090 Multi-arch support is enabled for all MIPS configurations.
6092 GDB can now be built as native debugger on SGI Irix 6.x systems for
6093 debugging n32 executables. (Debugging 64-bit executables is not yet
6096 * Unified support for hardware watchpoints in all x86 configurations.
6098 Most (if not all) native x86 configurations support hardware-assisted
6099 breakpoints and watchpoints in a unified manner. This support
6100 implements debug register sharing between watchpoints, which allows to
6101 put a virtually infinite number of watchpoints on the same address,
6102 and also supports watching regions up to 16 bytes with several debug
6105 The new maintenance command `maintenance show-debug-regs' toggles
6106 debugging print-outs in functions that insert, remove, and test
6107 watchpoints and hardware breakpoints.
6109 * Changes in the DJGPP native configuration.
6111 New command ``info dos sysinfo'' displays assorted information about
6112 the CPU, OS, memory, and DPMI server.
6114 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
6115 display information about segment descriptors stored in GDT, LDT, and
6118 New commands ``info dos pde'' and ``info dos pte'' display entries
6119 from Page Directory and Page Tables (for now works with CWSDPMI only).
6120 New command ``info dos address-pte'' displays the Page Table entry for
6121 a given linear address.
6123 GDB can now pass command lines longer than 126 characters to the
6124 program being debugged (requires an update to the libdbg.a library
6125 which is part of the DJGPP development kit).
6127 DWARF2 debug info is now supported.
6129 It is now possible to `step' and `next' through calls to `longjmp'.
6131 * Changes in documentation.
6133 All GDB documentation was converted to GFDL, the GNU Free
6134 Documentation License.
6136 Tracepoints-related commands are now fully documented in the GDB
6139 TUI, the Text-mode User Interface, is now documented in the manual.
6141 Tracepoints-related commands are now fully documented in the GDB
6144 The "GDB Internals" manual now has an index. It also includes
6145 documentation of `ui_out' functions, GDB coding standards, x86
6146 hardware watchpoints, and memory region attributes.
6148 * GDB's version number moved to ``version.in''
6150 The Makefile variable VERSION has been replaced by the file
6151 ``version.in''. People creating GDB distributions should update the
6152 contents of this file.
6156 GUD support is now a standard part of the EMACS distribution.
6158 *** Changes in GDB 5.0:
6160 * Improved support for debugging FP programs on x86 targets
6162 Unified and much-improved support for debugging floating-point
6163 programs on all x86 targets. In particular, ``info float'' now
6164 displays the FP registers in the same format on all x86 targets, with
6165 greater level of detail.
6167 * Improvements and bugfixes in hardware-assisted watchpoints
6169 It is now possible to watch array elements, struct members, and
6170 bitfields with hardware-assisted watchpoints. Data-read watchpoints
6171 on x86 targets no longer erroneously trigger when the address is
6174 * Improvements in the native DJGPP version of GDB
6176 The distribution now includes all the scripts and auxiliary files
6177 necessary to build the native DJGPP version on MS-DOS/MS-Windows
6178 machines ``out of the box''.
6180 The DJGPP version can now debug programs that use signals. It is
6181 possible to catch signals that happened in the debuggee, deliver
6182 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
6183 would kill the program being debugged.) Programs that hook hardware
6184 interrupts (keyboard, timer, etc.) can also be debugged.
6186 It is now possible to debug DJGPP programs that redirect their
6187 standard handles or switch them to raw (as opposed to cooked) mode, or
6188 even close them. The command ``run < foo > bar'' works as expected,
6189 and ``info terminal'' reports useful information about the debuggee's
6190 terminal, including raw/cooked mode, redirection, etc.
6192 The DJGPP version now uses termios functions for console I/O, which
6193 enables debugging graphics programs. Interrupting GDB with Ctrl-C
6196 DOS-style file names with drive letters are now fully supported by
6199 It is now possible to debug DJGPP programs that switch their working
6200 directory. It is also possible to rerun the debuggee any number of
6201 times without restarting GDB; thus, you can use the same setup,
6202 breakpoints, etc. for many debugging sessions.
6204 * New native configurations
6206 ARM GNU/Linux arm*-*-linux*
6207 PowerPC GNU/Linux powerpc-*-linux*
6211 Motorola MCore mcore-*-*
6212 x86 VxWorks i[3456]86-*-vxworks*
6213 PowerPC VxWorks powerpc-*-vxworks*
6214 TI TMS320C80 tic80-*-*
6216 * OBSOLETE configurations
6218 Altos 3068 m68*-altos-*
6219 Convex c1-*-*, c2-*-*
6221 ARM RISCix arm-*-* (as host)
6224 Configurations that have been declared obsolete will be commented out,
6225 but the code will be left in place. If there is no activity to revive
6226 these configurations before the next release of GDB, the sources will
6227 be permanently REMOVED.
6229 * Gould support removed
6231 Support for the Gould PowerNode and NP1 has been removed.
6233 * New features for SVR4
6235 On SVR4 native platforms (such as Solaris), if you attach to a process
6236 without first loading a symbol file, GDB will now attempt to locate and
6237 load symbols from the running process's executable file.
6239 * Many C++ enhancements
6241 C++ support has been greatly improved. Overload resolution now works properly
6242 in almost all cases. RTTI support is on the way.
6244 * Remote targets can connect to a sub-program
6246 A popen(3) style serial-device has been added. This device starts a
6247 sub-process (such as a stand-alone simulator) and then communicates
6248 with that. The sub-program to run is specified using the syntax
6249 ``|<program> <args>'' vis:
6251 (gdb) set remotedebug 1
6252 (gdb) target extended-remote |mn10300-elf-sim program-args
6254 * MIPS 64 remote protocol
6256 A long standing bug in the mips64 remote protocol where by GDB
6257 expected certain 32 bit registers (ex SR) to be transfered as 32
6258 instead of 64 bits has been fixed.
6260 The command ``set remote-mips64-transfers-32bit-regs on'' has been
6261 added to provide backward compatibility with older versions of GDB.
6263 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
6265 The command ``set remotebinarydownload'' command has been replaced by
6266 ``set remote X-packet''. Other commands in ``set remote'' family
6267 include ``set remote P-packet''.
6269 * Breakpoint commands accept ranges.
6271 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
6272 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
6273 ``tracepoint passcount'' also accepts a range of tracepoints.
6275 * ``apropos'' command added.
6277 The ``apropos'' command searches through command names and
6278 documentation strings, printing out matches, making it much easier to
6279 try to find a command that does what you are looking for.
6283 A new machine oriented interface (MI) has been added to GDB. This
6284 interface is designed for debug environments running GDB as a separate
6285 process. This is part of the long term libGDB project. See the
6286 "GDB/MI" chapter of the GDB manual for further information. It can be
6287 enabled by configuring with:
6289 .../configure --enable-gdbmi
6291 *** Changes in GDB-4.18:
6293 * New native configurations
6295 HP-UX 10.20 hppa*-*-hpux10.20
6296 HP-UX 11.x hppa*-*-hpux11.0*
6297 M68K GNU/Linux m68*-*-linux*
6301 Fujitsu FR30 fr30-*-elf*
6302 Intel StrongARM strongarm-*-*
6303 Mitsubishi D30V d30v-*-*
6305 * OBSOLETE configurations
6307 Gould PowerNode, NP1 np1-*-*, pn-*-*
6309 Configurations that have been declared obsolete will be commented out,
6310 but the code will be left in place. If there is no activity to revive
6311 these configurations before the next release of GDB, the sources will
6312 be permanently REMOVED.
6316 As a compatibility experiment, GDB's source files buildsym.h and
6317 buildsym.c have been converted to pure standard C, no longer
6318 containing any K&R compatibility code. We believe that all systems in
6319 use today either come with a standard C compiler, or have a GCC port
6320 available. If this is not true, please report the affected
6321 configuration to bug-gdb@gnu.org immediately. See the README file for
6322 information about getting a standard C compiler if you don't have one
6327 GDB now uses readline 2.2.
6329 * set extension-language
6331 You can now control the mapping between filename extensions and source
6332 languages by using the `set extension-language' command. For instance,
6333 you can ask GDB to treat .c files as C++ by saying
6334 set extension-language .c c++
6335 The command `info extensions' lists all of the recognized extensions
6336 and their associated languages.
6338 * Setting processor type for PowerPC and RS/6000
6340 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
6341 you can use the `set processor' command to specify what variant of the
6342 PowerPC family you are debugging. The command
6346 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
6347 following PowerPC and RS6000 variants:
6349 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
6350 rs6000 IBM RS6000 ("POWER") architecture, user-level view
6352 403GC IBM PowerPC 403GC
6353 505 Motorola PowerPC 505
6354 860 Motorola PowerPC 860 or 850
6355 601 Motorola PowerPC 601
6356 602 Motorola PowerPC 602
6357 603 Motorola/IBM PowerPC 603 or 603e
6358 604 Motorola PowerPC 604 or 604e
6359 750 Motorola/IBM PowerPC 750 or 750
6361 At the moment, this command just tells GDB what to name the
6362 special-purpose processor registers. Since almost all the affected
6363 registers are inaccessible to user-level programs, this command is
6364 only useful for remote debugging in its present form.
6368 Thanks to a major code donation from Hewlett-Packard, GDB now has much
6369 more extensive support for HP-UX. Added features include shared
6370 library support, kernel threads and hardware watchpoints for 11.00,
6371 support for HP's ANSI C and C++ compilers, and a compatibility mode
6372 for xdb and dbx commands.
6376 HP's donation includes the new concept of catchpoints, which is a
6377 generalization of the old catch command. On HP-UX, it is now possible
6378 to catch exec, fork, and vfork, as well as library loading.
6380 This means that the existing catch command has changed; its first
6381 argument now specifies the type of catch to be set up. See the
6382 output of "help catch" for a list of catchpoint types.
6384 * Debugging across forks
6386 On HP-UX, you can choose which process to debug when a fork() happens
6391 HP has donated a curses-based terminal user interface (TUI). To get
6392 it, build with --enable-tui. Although this can be enabled for any
6393 configuration, at present it only works for native HP debugging.
6395 * GDB remote protocol additions
6397 A new protocol packet 'X' that writes binary data is now available.
6398 Default behavior is to try 'X', then drop back to 'M' if the stub
6399 fails to respond. The settable variable `remotebinarydownload'
6400 allows explicit control over the use of 'X'.
6402 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
6403 full 64-bit address. The command
6405 set remoteaddresssize 32
6407 can be used to revert to the old behaviour. For existing remote stubs
6408 the change should not be noticed, as the additional address information
6411 In order to assist in debugging stubs, you may use the maintenance
6412 command `packet' to send any text string to the stub. For instance,
6414 maint packet heythere
6416 sends the packet "$heythere#<checksum>". Note that it is very easy to
6417 disrupt a debugging session by sending the wrong packet at the wrong
6420 The compare-sections command allows you to compare section data on the
6421 target to what is in the executable file without uploading or
6422 downloading, by comparing CRC checksums.
6424 * Tracing can collect general expressions
6426 You may now collect general expressions at tracepoints. This requires
6427 further additions to the target-side stub; see tracepoint.c and
6428 doc/agentexpr.texi for further details.
6430 * mask-address variable for Mips
6432 For Mips targets, you may control the zeroing of the upper 32 bits of
6433 a 64-bit address by entering `set mask-address on'. This is mainly
6434 of interest to users of embedded R4xxx and R5xxx processors.
6436 * Higher serial baud rates
6438 GDB's serial code now allows you to specify baud rates 57600, 115200,
6439 230400, and 460800 baud. (Note that your host system may not be able
6440 to achieve all of these rates.)
6444 The i960 configuration now includes an initial implementation of a
6445 builtin simulator, contributed by Jim Wilson.
6448 *** Changes in GDB-4.17:
6450 * New native configurations
6452 Alpha GNU/Linux alpha*-*-linux*
6453 Unixware 2.x i[3456]86-unixware2*
6454 Irix 6.x mips*-sgi-irix6*
6455 PowerPC GNU/Linux powerpc-*-linux*
6456 PowerPC Solaris powerpcle-*-solaris*
6457 Sparc GNU/Linux sparc-*-linux*
6458 Motorola sysV68 R3V7.1 m68k-motorola-sysv
6462 Argonaut Risc Chip (ARC) arc-*-*
6463 Hitachi H8/300S h8300*-*-*
6464 Matsushita MN10200 w/simulator mn10200-*-*
6465 Matsushita MN10300 w/simulator mn10300-*-*
6466 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
6467 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
6468 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
6469 Mitsubishi D10V w/simulator d10v-*-*
6470 Mitsubishi M32R/D w/simulator m32r-*-elf*
6471 Tsqware Sparclet sparclet-*-*
6472 NEC V850 w/simulator v850-*-*
6474 * New debugging protocols
6476 ARM with RDI protocol arm*-*-*
6477 M68K with dBUG monitor m68*-*-{aout,coff,elf}
6478 DDB and LSI variants of PMON protocol mips*-*-*
6479 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
6480 PowerPC with SDS protocol powerpc{,le}-*-eabi
6481 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6485 All configurations can now understand and use the DWARF 2 debugging
6486 format. The choice is automatic, if the symbol file contains DWARF 2
6491 GDB now includes basic Java language support. This support is
6492 only useful with Java compilers that produce native machine code.
6494 * solib-absolute-prefix and solib-search-path
6496 For SunOS and SVR4 shared libraries, you may now set the prefix for
6497 loading absolute shared library symbol files, and the search path for
6498 locating non-absolute shared library symbol files.
6500 * Live range splitting
6502 GDB can now effectively debug code for which GCC has performed live
6503 range splitting as part of its optimization. See gdb/doc/LRS for
6504 more details on the expected format of the stabs information.
6508 GDB's support for the GNU Hurd, including thread debugging, has been
6509 updated to work with current versions of the Hurd.
6513 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6514 instruction set. ARM GDB automatically detects when Thumb
6515 instructions are in use, and adjusts disassembly and backtracing
6520 GDB's MIPS target configurations now handle the MIP16 16-bit
6525 GDB now includes support for overlays; if an executable has been
6526 linked such that multiple sections are based at the same address, GDB
6527 will decide which section to use for symbolic info. You can choose to
6528 control the decision manually, using overlay commands, or implement
6529 additional target-side support and use "overlay load-target" to bring
6530 in the overlay mapping. Do "help overlay" for more detail.
6534 The command "info symbol <address>" displays information about
6535 the symbol at the specified address.
6539 The standard remote protocol now includes an extension that allows
6540 asynchronous collection and display of trace data. This requires
6541 extensive support in the target-side debugging stub. Tracing mode
6542 includes a new interaction mode in GDB and new commands: see the
6543 file tracepoint.c for more details.
6547 Configurations for embedded MIPS now include a simulator contributed
6548 by Cygnus Solutions. The simulator supports the instruction sets
6549 of most MIPS variants.
6553 Sparc configurations may now include the ERC32 simulator contributed
6554 by the European Space Agency. The simulator is not built into
6555 Sparc targets by default; configure with --enable-sim to include it.
6559 For target configurations that may include multiple variants of a
6560 basic architecture (such as MIPS and SH), you may now set the
6561 architecture explicitly. "set arch" sets, "info arch" lists
6562 the possible architectures.
6564 *** Changes in GDB-4.16:
6566 * New native configurations
6568 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6569 M68K NetBSD m68k-*-netbsd*
6570 PowerPC AIX 4.x powerpc-*-aix*
6571 PowerPC MacOS powerpc-*-macos*
6572 PowerPC Windows NT powerpcle-*-cygwin32
6573 RS/6000 AIX 4.x rs6000-*-aix4*
6577 ARM with RDP protocol arm-*-*
6578 I960 with MON960 i960-*-coff
6579 MIPS VxWorks mips*-*-vxworks*
6580 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6581 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6583 Matra Sparclet sparclet-*-*
6587 The powerpc-eabi configuration now includes the PSIM simulator,
6588 contributed by Andrew Cagney, with assistance from Mike Meissner.
6589 PSIM is a very elaborate model of the PowerPC, including not only
6590 basic instruction set execution, but also details of execution unit
6591 performance and I/O hardware. See sim/ppc/README for more details.
6595 GDB now works with Solaris 2.5.
6597 * Windows 95/NT native
6599 GDB will now work as a native debugger on Windows 95 and Windows NT.
6600 To build it from source, you must use the "gnu-win32" environment,
6601 which uses a DLL to emulate enough of Unix to run the GNU tools.
6602 Further information, binaries, and sources are available at
6603 ftp.cygnus.com, under pub/gnu-win32.
6605 * dont-repeat command
6607 If a user-defined command includes the command `dont-repeat', then the
6608 command will not be repeated if the user just types return. This is
6609 useful if the command is time-consuming to run, so that accidental
6610 extra keystrokes don't run the same command many times.
6612 * Send break instead of ^C
6614 The standard remote protocol now includes an option to send a break
6615 rather than a ^C to the target in order to interrupt it. By default,
6616 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6618 * Remote protocol timeout
6620 The standard remote protocol includes a new variable `remotetimeout'
6621 that allows you to set the number of seconds before GDB gives up trying
6622 to read from the target. The default value is 2.
6624 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6626 By default GDB will automatically keep track of objects as they are
6627 loaded and unloaded by the dynamic linker. By using the command `set
6628 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6629 when shared library events occur, thus allowing you to set breakpoints
6630 in shared libraries which are explicitly loaded by the inferior.
6632 Note this feature does not work on hpux8. On hpux9 you must link
6633 /usr/lib/end.o into your program. This feature should work
6634 automatically on hpux10.
6636 * Irix 5.x hardware watchpoint support
6638 Irix 5 configurations now support the use of hardware watchpoints.
6640 * Mips protocol "SYN garbage limit"
6642 When debugging a Mips target using the `target mips' protocol, you
6643 may set the number of characters that GDB will ignore by setting
6644 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6645 every character. The default value is 1050.
6647 * Recording and replaying remote debug sessions
6649 If you set `remotelogfile' to the name of a file, gdb will write to it
6650 a recording of a remote debug session. This recording may then be
6651 replayed back to gdb using "gdbreplay". See gdbserver/README for
6652 details. This is useful when you have a problem with GDB while doing
6653 remote debugging; you can make a recording of the session and send it
6654 to someone else, who can then recreate the problem.
6656 * Speedups for remote debugging
6658 GDB includes speedups for downloading and stepping MIPS systems using
6659 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6660 and more efficient S-record downloading.
6662 * Memory use reductions and statistics collection
6664 GDB now uses less memory and reports statistics about memory usage.
6665 Try the `maint print statistics' command, for example.
6667 *** Changes in GDB-4.15:
6669 * Psymtabs for XCOFF
6671 The symbol reader for AIX GDB now uses partial symbol tables. This
6672 can greatly improve startup time, especially for large executables.
6674 * Remote targets use caching
6676 Remote targets now use a data cache to speed up communication with the
6677 remote side. The data cache could lead to incorrect results because
6678 it doesn't know about volatile variables, thus making it impossible to
6679 debug targets which use memory mapped I/O devices. `set remotecache
6680 off' turns the data cache off.
6682 * Remote targets may have threads
6684 The standard remote protocol now includes support for multiple threads
6685 in the target system, using new protocol commands 'H' and 'T'. See
6686 gdb/remote.c for details.
6690 If GDB is configured with `--enable-netrom', then it will include
6691 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6692 acts as though it is a bank of ROM on the target board, but you can
6693 write into it over the network. GDB's support consists only of
6694 support for fast loading into the emulated ROM; to debug, you must use
6695 another protocol, such as standard remote protocol. The usual
6696 sequence is something like
6698 target nrom <netrom-hostname>
6700 target remote <netrom-hostname>:1235
6704 GDB now includes support for the Apple Macintosh, as a host only. It
6705 may be run as either an MPW tool or as a standalone application, and
6706 it can debug through the serial port. All the usual GDB commands are
6707 available, but to the target command, you must supply "serial" as the
6708 device type instead of "/dev/ttyXX". See mpw-README in the main
6709 directory for more information on how to build. The MPW configuration
6710 scripts */mpw-config.in support only a few targets, and only the
6711 mips-idt-ecoff target has been tested.
6715 GDB configuration now uses autoconf. This is not user-visible,
6716 but does simplify configuration and building.
6720 GDB now supports hpux10.
6722 *** Changes in GDB-4.14:
6724 * New native configurations
6726 x86 FreeBSD i[345]86-*-freebsd
6727 x86 NetBSD i[345]86-*-netbsd
6728 NS32k NetBSD ns32k-*-netbsd
6729 Sparc NetBSD sparc-*-netbsd
6733 A29K VxWorks a29k-*-vxworks
6734 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6735 CPU32 EST-300 emulator m68*-*-est*
6736 PowerPC ELF powerpc-*-elf
6739 * Alpha OSF/1 support for procfs
6741 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6742 possible to attach to running processes. As the mounting of the /proc
6743 filesystem is optional on the Alpha, GDB automatically determines
6744 the availability of /proc during startup. This can lead to problems
6745 if /proc is unmounted after GDB has been started.
6747 * Arguments to user-defined commands
6749 User commands may accept up to 10 arguments separated by whitespace.
6750 Arguments are accessed within the user command via $arg0..$arg9. A
6753 print $arg0 + $arg1 + $arg2
6755 To execute the command use:
6758 Defines the command "adder" which prints the sum of its three arguments.
6759 Note the arguments are text substitutions, so they may reference variables,
6760 use complex expressions, or even perform inferior function calls.
6762 * New `if' and `while' commands
6764 This makes it possible to write more sophisticated user-defined
6765 commands. Both commands take a single argument, which is the
6766 expression to evaluate, and must be followed by the commands to
6767 execute, one per line, if the expression is nonzero, the list being
6768 terminated by the word `end'. The `if' command list may include an
6769 `else' word, which causes the following commands to be executed only
6770 if the expression is zero.
6772 * Fortran source language mode
6774 GDB now includes partial support for Fortran 77. It will recognize
6775 Fortran programs and can evaluate a subset of Fortran expressions, but
6776 variables and functions may not be handled correctly. GDB will work
6777 with G77, but does not yet know much about symbols emitted by other
6780 * Better HPUX support
6782 Most debugging facilities now work on dynamic executables for HPPAs
6783 running hpux9 or later. You can attach to running dynamically linked
6784 processes, but by default the dynamic libraries will be read-only, so
6785 for instance you won't be able to put breakpoints in them. To change
6786 that behavior do the following before running the program:
6792 This will cause the libraries to be mapped private and read-write.
6793 To revert to the normal behavior, do this:
6799 You cannot set breakpoints or examine data in the library until after
6800 the library is loaded if the function/data symbols do not have
6803 GDB can now also read debug symbols produced by the HP C compiler on
6804 HPPAs (sorry, no C++, Fortran or 68k support).
6806 * Target byte order now dynamically selectable
6808 You can choose which byte order to use with a target system, via the
6809 commands "set endian big" and "set endian little", and you can see the
6810 current setting by using "show endian". You can also give the command
6811 "set endian auto", in which case GDB will use the byte order
6812 associated with the executable. Currently, only embedded MIPS
6813 configurations support dynamic selection of target byte order.
6815 * New DOS host serial code
6817 This version uses DPMI interrupts to handle buffered I/O, so you
6818 no longer need to run asynctsr when debugging boards connected to
6821 *** Changes in GDB-4.13:
6823 * New "complete" command
6825 This lists all the possible completions for the rest of the line, if it
6826 were to be given as a command itself. This is intended for use by emacs.
6828 * Trailing space optional in prompt
6830 "set prompt" no longer adds a space for you after the prompt you set. This
6831 allows you to set a prompt which ends in a space or one that does not.
6833 * Breakpoint hit counts
6835 "info break" now displays a count of the number of times the breakpoint
6836 has been hit. This is especially useful in conjunction with "ignore"; you
6837 can ignore a large number of breakpoint hits, look at the breakpoint info
6838 to see how many times the breakpoint was hit, then run again, ignoring one
6839 less than that number, and this will get you quickly to the last hit of
6842 * Ability to stop printing at NULL character
6844 "set print null-stop" will cause GDB to stop printing the characters of
6845 an array when the first NULL is encountered. This is useful when large
6846 arrays actually contain only short strings.
6848 * Shared library breakpoints
6850 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6851 breakpoints in shared libraries before the executable is run.
6853 * Hardware watchpoints
6855 There is a new hardware breakpoint for the watch command for sparclite
6856 targets. See gdb/sparclite/hw_breakpoint.note.
6858 Hardware watchpoints are also now supported under GNU/Linux.
6862 Annotations have been added. These are for use with graphical interfaces,
6863 and are still experimental. Currently only gdba.el uses these.
6865 * Improved Irix 5 support
6867 GDB now works properly with Irix 5.2.
6869 * Improved HPPA support
6871 GDB now works properly with the latest GCC and GAS.
6873 * New native configurations
6875 Sequent PTX4 i[34]86-sequent-ptx4
6876 HPPA running OSF/1 hppa*-*-osf*
6877 Atari TT running SVR4 m68*-*-sysv4*
6878 RS/6000 LynxOS rs6000-*-lynxos*
6882 OS/9000 i[34]86-*-os9k
6883 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6886 * Hitachi SH7000 and E7000-PC ICE support
6888 There is now support for communicating with the Hitachi E7000-PC ICE.
6889 This is available automatically when GDB is configured for the SH.
6893 As usual, a variety of small fixes and improvements, both generic
6894 and configuration-specific. See the ChangeLog for more detail.
6896 *** Changes in GDB-4.12:
6898 * Irix 5 is now supported
6902 GDB-4.12 on the HPPA has a number of changes which make it unable
6903 to debug the output from the currently released versions of GCC and
6904 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6905 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6906 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6909 *** Changes in GDB-4.11:
6911 * User visible changes:
6915 The "set remotedebug" option is now consistent between the mips remote
6916 target, remote targets using the gdb-specific protocol, UDI (AMD's
6917 debug protocol for the 29k) and the 88k bug monitor. It is now an
6918 integer specifying a debug level (normally 0 or 1, but 2 means more
6919 debugging info for the mips target).
6921 * DEC Alpha native support
6923 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6924 debug info, but GDB works fairly well with the DEC compiler and should
6925 work with a future GCC release. See the README file for a few
6926 Alpha-specific notes.
6928 * Preliminary thread implementation
6930 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6932 * LynxOS native and target support for 386
6934 This release has been hosted on LynxOS 2.2, and also can be configured
6935 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6938 * Improvements in C++ mangling/demangling.
6940 This release has much better g++ debugging, specifically in name
6941 mangling/demangling, virtual function calls, print virtual table,
6942 call methods, ...etc.
6944 *** Changes in GDB-4.10:
6946 * User visible changes:
6948 Remote debugging using the GDB-specific (`target remote') protocol now
6949 supports the `load' command. This is only useful if you have some
6950 other way of getting the stub to the target system, and you can put it
6951 somewhere in memory where it won't get clobbered by the download.
6953 Filename completion now works.
6955 When run under emacs mode, the "info line" command now causes the
6956 arrow to point to the line specified. Also, "info line" prints
6957 addresses in symbolic form (as well as hex).
6959 All vxworks based targets now support a user settable option, called
6960 vxworks-timeout. This option represents the number of seconds gdb
6961 should wait for responses to rpc's. You might want to use this if
6962 your vxworks target is, perhaps, a slow software simulator or happens
6963 to be on the far side of a thin network line.
6967 This release contains support for using a DEC alpha as a GDB host for
6968 cross debugging. Native alpha debugging is not supported yet.
6971 *** Changes in GDB-4.9:
6975 This is the first GDB release which is accompanied by a matching testsuite.
6976 The testsuite requires installation of dejagnu, which should be available
6977 via ftp from most sites that carry GNU software.
6981 'Cfront' style demangling has had its name changed to 'ARM' style, to
6982 emphasize that it was written from the specifications in the C++ Annotated
6983 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6984 disclaimers, it still generated too much confusion with users attempting to
6985 use gdb with AT&T cfront.
6989 GDB now uses a standard remote interface to a simulator library.
6990 So far, the library contains simulators for the Zilog Z8001/2, the
6991 Hitachi H8/300, H8/500 and Super-H.
6993 * New targets supported
6995 H8/300 simulator h8300-hitachi-hms or h8300hms
6996 H8/500 simulator h8500-hitachi-hms or h8500hms
6997 SH simulator sh-hitachi-hms or sh
6998 Z8000 simulator z8k-zilog-none or z8ksim
6999 IDT MIPS board over serial line mips-idt-ecoff
7001 Cross-debugging to GO32 targets is supported. It requires a custom
7002 version of the i386-stub.c module which is integrated with the
7003 GO32 memory extender.
7005 * New remote protocols
7007 MIPS remote debugging protocol.
7009 * New source languages supported
7011 This version includes preliminary support for Chill, a Pascal like language
7012 used by telecommunications companies. Chill support is also being integrated
7013 into the GNU compiler, but we don't know when it will be publically available.
7016 *** Changes in GDB-4.8:
7018 * HP Precision Architecture supported
7020 GDB now supports HP PA-RISC machines running HPUX. A preliminary
7021 version of this support was available as a set of patches from the
7022 University of Utah. GDB does not support debugging of programs
7023 compiled with the HP compiler, because HP will not document their file
7024 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
7025 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
7027 Many problems in the preliminary version have been fixed.
7029 * Faster and better demangling
7031 We have improved template demangling and fixed numerous bugs in the GNU style
7032 demangler. It can now handle type modifiers such as `static' or `const'. Wide
7033 character types (wchar_t) are now supported. Demangling of each symbol is now
7034 only done once, and is cached when the symbol table for a file is read in.
7035 This results in a small increase in memory usage for C programs, a moderate
7036 increase in memory usage for C++ programs, and a fantastic speedup in
7039 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
7040 from the specifications in the Annotated Reference Manual, which AT&T's
7041 compiler does not actually implement.
7043 * G++ multiple inheritance compiler problem
7045 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
7046 inheritance lattices was reworked to properly discover ambiguities. We
7047 recently found an example which causes this new algorithm to fail in a
7048 very subtle way, producing bad debug information for those classes.
7049 The file 'gcc.patch' (in this directory) can be applied to gcc to
7050 circumvent the problem. A future GCC release will contain a complete
7053 The previous G++ debug info problem (mentioned below for the gdb-4.7
7054 release) is fixed in gcc version 2.3.2.
7056 * Improved configure script
7058 The `configure' script will now attempt to guess your system type if
7059 you don't supply a host system type. The old scheme of supplying a
7060 host system triplet is preferable over using this. All the magic is
7061 done in the new `config.guess' script. Examine it for details.
7063 We have also brought our configure script much more in line with the FSF's
7064 version. It now supports the --with-xxx options. In particular,
7065 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
7066 The resulting GDB will not be able to read arbitrary object file formats --
7067 only the format ``expected'' to be used on the configured target system.
7068 We hope to make this the default in a future release.
7070 * Documentation improvements
7072 There's new internal documentation on how to modify GDB, and how to
7073 produce clean changes to the code. We implore people to read it
7074 before submitting changes.
7076 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
7077 M4 macros. The new texinfo.tex is provided in this release. Pre-built
7078 `info' files are also provided. To build `info' files from scratch,
7079 you will need the latest `makeinfo' release, which will be available in
7080 a future texinfo-X.Y release.
7082 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
7083 We're not sure exactly which versions have this problem, but it has
7084 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
7085 or better. If that isn't possible, there is a patch in
7086 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
7087 around this problem.
7091 GDB now supports array constants that can be used in expressions typed in by
7092 the user. The syntax is `{element, element, ...}'. Ie: you can now type
7093 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
7096 The new directory `gdb/sparclite' contains a program that demonstrates
7097 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
7099 * New native hosts supported
7101 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
7102 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
7104 * New targets supported
7106 AMD 29k family via UDI a29k-amd-udi or udi29k
7108 * New file formats supported
7110 BFD now supports reading HP/PA-RISC executables (SOM file format?),
7111 HPUX core files, and SCO 3.2v2 core files.
7115 Attaching to processes now works again; thanks for the many bug reports.
7117 We have also stomped on a bunch of core dumps caused by
7118 printf_filtered("%s") problems.
7120 We eliminated a copyright problem on the rpc and ptrace header files
7121 for VxWorks, which was discovered at the last minute during the 4.7
7122 release. You should now be able to build a VxWorks GDB.
7124 You can now interrupt gdb while an attached process is running. This
7125 will cause the attached process to stop, and give control back to GDB.
7127 We fixed problems caused by using too many file descriptors
7128 for reading symbols from object files and libraries. This was
7129 especially a problem for programs that used many (~100) shared
7132 The `step' command now only enters a subroutine if there is line number
7133 information for the subroutine. Otherwise it acts like the `next'
7134 command. Previously, `step' would enter subroutines if there was
7135 any debugging information about the routine. This avoids problems
7136 when using `cc -g1' on MIPS machines.
7138 * Internal improvements
7140 GDB's internal interfaces have been improved to make it easier to support
7141 debugging of multiple languages in the future.
7143 GDB now uses a common structure for symbol information internally.
7144 Minimal symbols (derived from linkage symbols in object files), partial
7145 symbols (from a quick scan of debug information), and full symbols
7146 contain a common subset of information, making it easier to write
7147 shared code that handles any of them.
7149 * New command line options
7151 We now accept --silent as an alias for --quiet.
7155 The memory-mapped-malloc library is now licensed under the GNU Library
7156 General Public License.
7158 *** Changes in GDB-4.7:
7160 * Host/native/target split
7162 GDB has had some major internal surgery to untangle the support for
7163 hosts and remote targets. Now, when you configure GDB for a remote
7164 target, it will no longer load in all of the support for debugging
7165 local programs on the host. When fully completed and tested, this will
7166 ensure that arbitrary host/target combinations are possible.
7168 The primary conceptual shift is to separate the non-portable code in
7169 GDB into three categories. Host specific code is required any time GDB
7170 is compiled on that host, regardless of the target. Target specific
7171 code relates to the peculiarities of the target, but can be compiled on
7172 any host. Native specific code is everything else: it can only be
7173 built when the host and target are the same system. Child process
7174 handling and core file support are two common `native' examples.
7176 GDB's use of /proc for controlling Unix child processes is now cleaner.
7177 It has been split out into a single module under the `target_ops' vector,
7178 plus two native-dependent functions for each system that uses /proc.
7180 * New hosts supported
7182 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
7183 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7184 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
7186 * New targets supported
7188 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
7189 68030 and CPU32 m68030-*-*, m68332-*-*
7191 * New native hosts supported
7193 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7194 (386bsd is not well tested yet)
7195 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
7197 * New file formats supported
7199 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
7200 supports reading of `a.out.adobe' object files, which are an a.out
7201 format extended with minimal information about multiple sections.
7205 `show copying' is the same as the old `info copying'.
7206 `show warranty' is the same as `info warrantee'.
7207 These were renamed for consistency. The old commands continue to work.
7209 `info handle' is a new alias for `info signals'.
7211 You can now define pre-command hooks, which attach arbitrary command
7212 scripts to any command. The commands in the hook will be executed
7213 prior to the user's command. You can also create a hook which will be
7214 executed whenever the program stops. See gdb.texinfo.
7218 We now deal with Cfront style name mangling, and can even extract type
7219 info from mangled symbols. GDB can automatically figure out which
7220 symbol mangling style your C++ compiler uses.
7222 Calling of methods and virtual functions has been improved as well.
7226 The crash that occurred when debugging Sun Ansi-C compiled binaries is
7227 fixed. This was due to mishandling of the extra N_SO stabs output
7230 We also finally got Ultrix 4.2 running in house, and fixed core file
7231 support, with help from a dozen people on the net.
7233 John M. Farrell discovered that the reason that single-stepping was so
7234 slow on all of the Mips based platforms (primarily SGI and DEC) was
7235 that we were trying to demangle and lookup a symbol used for internal
7236 purposes on every instruction that was being stepped through. Changing
7237 the name of that symbol so that it couldn't be mistaken for a C++
7238 mangled symbol sped things up a great deal.
7240 Rich Pixley sped up symbol lookups in general by getting much smarter
7241 about when C++ symbol mangling is necessary. This should make symbol
7242 completion (TAB on the command line) much faster. It's not as fast as
7243 we'd like, but it's significantly faster than gdb-4.6.
7247 A new user controllable variable 'call_scratch_address' can
7248 specify the location of a scratch area to be used when GDB
7249 calls a function in the target. This is necessary because the
7250 usual method of putting the scratch area on the stack does not work
7251 in systems that have separate instruction and data spaces.
7253 We integrated changes to support the 29k UDI (Universal Debugger
7254 Interface), but discovered at the last minute that we didn't have all
7255 of the appropriate copyright paperwork. We are working with AMD to
7256 resolve this, and hope to have it available soon.
7260 We have sped up the remote serial line protocol, especially for targets
7261 with lots of registers. It now supports a new `expedited status' ('T')
7262 message which can be used in place of the existing 'S' status message.
7263 This allows the remote stub to send only the registers that GDB
7264 needs to make a quick decision about single-stepping or conditional
7265 breakpoints, eliminating the need to fetch the entire register set for
7266 each instruction being stepped through.
7268 The GDB remote serial protocol now implements a write-through cache for
7269 registers, only re-reading the registers if the target has run.
7271 There is also a new remote serial stub for SPARC processors. You can
7272 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
7273 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
7274 processor with a serial port.
7278 Configure.in files have become much easier to read and modify. A new
7279 `table driven' format makes it more obvious what configurations are
7280 supported, and what files each one uses.
7284 There is a new opcodes library which will eventually contain all of the
7285 disassembly routines and opcode tables. At present, it only contains
7286 Sparc and Z8000 routines. This will allow the assembler, debugger, and
7287 disassembler (binutils/objdump) to share these routines.
7289 The libiberty library is now copylefted under the GNU Library General
7290 Public License. This allows more liberal use, and was done so libg++
7291 can use it. This makes no difference to GDB, since the Library License
7292 grants all the rights from the General Public License.
7296 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
7297 reference to the stabs symbol info used by the debugger. It is (as far
7298 as we know) the only published document on this fascinating topic. We
7299 encourage you to read it, compare it to the stabs information on your
7300 system, and send improvements on the document in general (to
7301 bug-gdb@prep.ai.mit.edu).
7303 And, of course, many bugs have been fixed.
7306 *** Changes in GDB-4.6:
7308 * Better support for C++ function names
7310 GDB now accepts as input the "demangled form" of C++ overloaded function
7311 names and member function names, and can do command completion on such names
7312 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
7313 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
7314 Make use of command completion, it is your friend.
7316 GDB also now accepts a variety of C++ mangled symbol formats. They are
7317 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
7318 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
7319 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
7320 for the list of formats.
7322 * G++ symbol mangling problem
7324 Recent versions of gcc have a bug in how they emit debugging information for
7325 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
7326 directory) can be applied to gcc to fix the problem. Alternatively, if you
7327 can't fix gcc, you can #define GCC_MANGLE_BUG when compiling gdb/symtab.c. The
7328 usual symptom is difficulty with setting breakpoints on methods. GDB complains
7329 about the method being non-existent. (We believe that version 2.2.2 of GCC has
7332 * New 'maintenance' command
7334 All of the commands related to hacking GDB internals have been moved out of
7335 the main command set, and now live behind the 'maintenance' command. This
7336 can also be abbreviated as 'mt'. The following changes were made:
7338 dump-me -> maintenance dump-me
7339 info all-breakpoints -> maintenance info breakpoints
7340 printmsyms -> maintenance print msyms
7341 printobjfiles -> maintenance print objfiles
7342 printpsyms -> maintenance print psymbols
7343 printsyms -> maintenance print symbols
7345 The following commands are new:
7347 maintenance demangle Call internal GDB demangler routine to
7348 demangle a C++ link name and prints the result.
7349 maintenance print type Print a type chain for a given symbol
7351 * Change to .gdbinit file processing
7353 We now read the $HOME/.gdbinit file before processing the argv arguments
7354 (e.g. reading symbol files or core files). This allows global parameters to
7355 be set, which will apply during the symbol reading. The ./.gdbinit is still
7356 read after argv processing.
7358 * New hosts supported
7360 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
7362 GNU/Linux support i386-unknown-linux or linux
7364 We are also including code to support the HP/PA running BSD and HPUX. This
7365 is almost guaranteed not to work, as we didn't have time to test or build it
7366 for this release. We are including it so that the more adventurous (or
7367 masochistic) of you can play with it. We also had major problems with the
7368 fact that the compiler that we got from HP doesn't support the -g option.
7371 * New targets supported
7373 Hitachi H8/300 h8300-hitachi-hms or h8300hms
7375 * More smarts about finding #include files
7377 GDB now remembers the compilation directory for all include files, and for
7378 all files from which C is generated (like yacc and lex sources). This
7379 greatly improves GDB's ability to find yacc/lex sources, and include files,
7380 especially if you are debugging your program from a directory different from
7381 the one that contains your sources.
7383 We also fixed a bug which caused difficulty with listing and setting
7384 breakpoints in include files which contain C code. (In the past, you had to
7385 try twice in order to list an include file that you hadn't looked at before.)
7387 * Interesting infernals change
7389 GDB now deals with arbitrary numbers of sections, where the symbols for each
7390 section must be relocated relative to that section's landing place in the
7391 target's address space. This work was needed to support ELF with embedded
7392 stabs used by Solaris-2.0.
7394 * Bug fixes (of course!)
7396 There have been loads of fixes for the following things:
7397 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
7398 i960, stabs, DOS(GO32), procfs, etc...
7400 See the ChangeLog for details.
7402 *** Changes in GDB-4.5:
7404 * New machines supported (host and target)
7406 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
7408 SGI Irix-4.x mips-sgi-irix4 or iris4
7410 * New malloc package
7412 GDB now uses a new memory manager called mmalloc, based on gmalloc.
7413 Mmalloc is capable of handling multiple heaps of memory. It is also
7414 capable of saving a heap to a file, and then mapping it back in later.
7415 This can be used to greatly speedup the startup of GDB by using a
7416 pre-parsed symbol table which lives in a mmalloc managed heap. For
7417 more details, please read mmalloc/mmalloc.texi.
7421 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
7422 'help info proc' for details.
7424 * MIPS ecoff symbol table format
7426 The code that reads MIPS symbol table format is now supported on all hosts.
7427 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
7430 * File name changes for MS-DOS
7432 Many files in the config directories have been renamed to make it easier to
7433 support GDB on MS-DOSe systems (which have very restrictive file name
7434 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
7435 environment) is close to working but has some remaining problems. Note
7436 that debugging of DOS programs is not supported, due to limitations
7437 in the ``operating system'', but it can be used to host cross-debugging.
7439 * Cross byte order fixes
7441 Many fixes have been made to support cross debugging of Sparc and MIPS
7442 targets from hosts whose byte order differs.
7444 * New -mapped and -readnow options
7446 If memory-mapped files are available on your system through the 'mmap'
7447 system call, you can use the -mapped option on the `file' or
7448 `symbol-file' commands to cause GDB to write the symbols from your
7449 program into a reusable file. If the program you are debugging is
7450 called `/path/fred', the mapped symbol file will be `./fred.syms'.
7451 Future GDB debugging sessions will notice the presence of this file,
7452 and will quickly map in symbol information from it, rather than reading
7453 the symbol table from the executable program. Using the '-mapped'
7454 option in a GDB `file' or `symbol-file' command has the same effect as
7455 starting GDB with the '-mapped' command-line option.
7457 You can cause GDB to read the entire symbol table immediately by using
7458 the '-readnow' option with any of the commands that load symbol table
7459 information (or on the GDB command line). This makes the command
7460 slower, but makes future operations faster.
7462 The -mapped and -readnow options are typically combined in order to
7463 build a `fred.syms' file that contains complete symbol information.
7464 A simple GDB invocation to do nothing but build a `.syms' file for future
7467 gdb -batch -nx -mapped -readnow programname
7469 The `.syms' file is specific to the host machine on which GDB is run.
7470 It holds an exact image of GDB's internal symbol table. It cannot be
7471 shared across multiple host platforms.
7473 * longjmp() handling
7475 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
7476 siglongjmp() without losing control. This feature has not yet been ported to
7477 all systems. It currently works on many 386 platforms, all MIPS-based
7478 platforms (SGI, DECstation, etc), and Sun3/4.
7482 Preliminary work has been put in to support the new Solaris OS from Sun. At
7483 this time, it can control and debug processes, but it is not capable of
7488 As always, many many bug fixes. The major areas were with g++, and mipsread.
7489 People using the MIPS-based platforms should experience fewer mysterious
7490 crashes and trashed symbol tables.
7492 *** Changes in GDB-4.4:
7494 * New machines supported (host and target)
7496 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7498 BSD Reno on Vax vax-dec-bsd
7499 Ultrix on Vax vax-dec-ultrix
7501 * New machines supported (target)
7503 AMD 29000 embedded, using EBMON a29k-none-none
7507 GDB continues to improve its handling of C++. `References' work better.
7508 The demangler has also been improved, and now deals with symbols mangled as
7509 per the Annotated C++ Reference Guide.
7511 GDB also now handles `stabs' symbol information embedded in MIPS
7512 `ecoff' symbol tables. Since the ecoff format was not easily
7513 extensible to handle new languages such as C++, this appeared to be a
7514 good way to put C++ debugging info into MIPS binaries. This option
7515 will be supported in the GNU C compiler, version 2, when it is
7518 * New features for SVR4
7520 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7521 shared libraries. Debugging dynamically linked programs should present
7522 only minor differences from debugging statically linked programs.
7524 The `info proc' command will print out information about any process
7525 on an SVR4 system (including the one you are debugging). At the moment,
7526 it prints the address mappings of the process.
7528 If you bring up GDB on another SVR4 system, please send mail to
7529 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7531 * Better dynamic linking support in SunOS
7533 Reading symbols from shared libraries which contain debugging symbols
7534 now works properly. However, there remain issues such as automatic
7535 skipping of `transfer vector' code during function calls, which
7536 make it harder to debug code in a shared library, than to debug the
7537 same code linked statically.
7541 GDB is now using the latest `getopt' routines from the FSF. This
7542 version accepts the -- prefix for options with long names. GDB will
7543 continue to accept the old forms (-option and +option) as well.
7544 Various single letter abbreviations for options have been explicity
7545 added to the option table so that they won't get overshadowed in the
7546 future by other options that begin with the same letter.
7550 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7551 Many assorted bugs have been handled. Many more remain to be handled.
7552 See the various ChangeLog files (primarily in gdb and bfd) for details.
7555 *** Changes in GDB-4.3:
7557 * New machines supported (host and target)
7559 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7560 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7561 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7563 * Almost SCO Unix support
7565 We had hoped to support:
7566 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7567 (except for core file support), but we discovered very late in the release
7568 that it has problems with process groups that render gdb unusable. Sorry
7569 about that. I encourage people to fix it and post the fixes.
7571 * Preliminary ELF and DWARF support
7573 GDB can read ELF object files on System V Release 4, and can handle
7574 debugging records for C, in DWARF format, in ELF files. This support
7575 is preliminary. If you bring up GDB on another SVR4 system, please
7576 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7581 GDB now uses the latest `readline' library. One user-visible change
7582 is that two tabs will list possible command completions, which previously
7583 required typing M-? (meta-question mark, or ESC ?).
7587 The `stepi' bug that many of you noticed has been squashed.
7588 Many bugs in C++ have been handled. Many more remain to be handled.
7589 See the various ChangeLog files (primarily in gdb and bfd) for details.
7591 * State of the MIPS world (in case you wondered):
7593 GDB can understand the symbol tables emitted by the compilers
7594 supplied by most vendors of MIPS-based machines, including DEC. These
7595 symbol tables are in a format that essentially nobody else uses.
7597 Some versions of gcc come with an assembler post-processor called
7598 mips-tfile. This program is required if you want to do source-level
7599 debugging of gcc-compiled programs. I believe FSF does not ship
7600 mips-tfile with gcc version 1, but it will eventually come with gcc
7603 Debugging of g++ output remains a problem. g++ version 1.xx does not
7604 really support it at all. (If you're lucky, you should be able to get
7605 line numbers and stack traces to work, but no parameters or local
7606 variables.) With some work it should be possible to improve the
7609 When gcc version 2 is released, you will have somewhat better luck.
7610 However, even then you will get confusing results for inheritance and
7613 We will eventually provide full debugging of g++ output on
7614 DECstations. This will probably involve some kind of stabs-in-ecoff
7615 encapulation, but the details have not been worked out yet.
7618 *** Changes in GDB-4.2:
7620 * Improved configuration
7622 Only one copy of `configure' exists now, and it is not self-modifying.
7623 Porting BFD is simpler.
7627 The `step' and `next' commands now only stop at the first instruction
7628 of a source line. This prevents the multiple stops that used to occur
7629 in switch statements, for-loops, etc. `Step' continues to stop if a
7630 function that has debugging information is called within the line.
7634 Lots of small bugs fixed. More remain.
7636 * New host supported (not target)
7638 Intel 386 PC clone running Mach i386-none-mach
7641 *** Changes in GDB-4.1:
7643 * Multiple source language support
7645 GDB now has internal scaffolding to handle several source languages.
7646 It determines the type of each source file from its filename extension,
7647 and will switch expression parsing and number formatting to match the
7648 language of the function in the currently selected stack frame.
7649 You can also specifically set the language to be used, with
7650 `set language c' or `set language modula-2'.
7654 GDB now has preliminary support for the GNU Modula-2 compiler,
7655 currently under development at the State University of New York at
7656 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7657 continue through the fall of 1991 and into 1992.
7659 Other Modula-2 compilers are currently not supported, and attempting to
7660 debug programs compiled with them will likely result in an error as the
7661 symbol table is read. Feel free to work on it, though!
7663 There are hooks in GDB for strict type checking and range checking,
7664 in the `Modula-2 philosophy', but they do not currently work.
7668 GDB can now write to executable and core files (e.g. patch
7669 a variable's value). You must turn this switch on, specify
7670 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7671 by assigning a new value to a variable. Modifications take
7674 * Automatic SunOS shared library reading
7676 When you run your program, GDB automatically determines where its
7677 shared libraries (if any) have been loaded, and reads their symbols.
7678 The `share' command is no longer needed. This also works when
7679 examining core files.
7683 You can specify the number of lines that the `list' command shows.
7686 * New machines supported (host and target)
7688 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7689 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7690 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7692 * New hosts supported (not targets)
7694 IBM RT/PC: romp-ibm-aix or rtpc
7696 * New targets supported (not hosts)
7698 AMD 29000 embedded with COFF a29k-none-coff
7699 AMD 29000 embedded with a.out a29k-none-aout
7700 Ultracomputer remote kernel debug a29k-nyu-kern
7702 * New remote interfaces
7708 *** Changes in GDB-4.0:
7712 Wide output is wrapped at good places to make the output more readable.
7714 Gdb now supports cross-debugging from a host machine of one type to a
7715 target machine of another type. Communication with the target system
7716 is over serial lines. The ``target'' command handles connecting to the
7717 remote system; the ``load'' command will download a program into the
7718 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7719 also supports debugging of realtime processes running under VxWorks,
7720 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7721 stub on the target system.
7723 New CPUs supported include the AMD 29000 and Intel 960.
7725 GDB now reads object files and symbol tables via a ``binary file''
7726 library, which allows a single copy of GDB to debug programs of multiple
7727 object file types such as a.out and coff.
7729 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7730 refcard.dvi and refcard.ps are available to format it).
7733 * Control-Variable user interface simplified
7735 All variables that control the operation of the debugger can be set
7736 by the ``set'' command, and displayed by the ``show'' command.
7738 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7739 ``Show prompt'' produces the response:
7740 Gdb's prompt is new-gdb=>.
7742 What follows are the NEW set commands. The command ``help set'' will
7743 print a complete list of old and new set commands. ``help set FOO''
7744 will give a longer description of the variable FOO. ``show'' will show
7745 all of the variable descriptions and their current settings.
7747 confirm on/off: Enables warning questions for operations that are
7748 hard to recover from, e.g. rerunning the program while
7749 it is already running. Default is ON.
7751 editing on/off: Enables EMACS style command line editing
7752 of input. Previous lines can be recalled with
7753 control-P, the current line can be edited with control-B,
7754 you can search for commands with control-R, etc.
7757 history filename NAME: NAME is where the gdb command history
7758 will be stored. The default is .gdb_history,
7759 or the value of the environment variable
7762 history size N: The size, in commands, of the command history. The
7763 default is 256, or the value of the environment variable
7766 history save on/off: If this value is set to ON, the history file will
7767 be saved after exiting gdb. If set to OFF, the
7768 file will not be saved. The default is OFF.
7770 history expansion on/off: If this value is set to ON, then csh-like
7771 history expansion will be performed on
7772 command line input. The default is OFF.
7774 radix N: Sets the default radix for input and output. It can be set
7775 to 8, 10, or 16. Note that the argument to "radix" is interpreted
7776 in the current radix, so "set radix 10" is always a no-op.
7778 height N: This integer value is the number of lines on a page. Default
7779 is 24, the current `stty rows'' setting, or the ``li#''
7780 setting from the termcap entry matching the environment
7783 width N: This integer value is the number of characters on a line.
7784 Default is 80, the current `stty cols'' setting, or the ``co#''
7785 setting from the termcap entry matching the environment
7788 Note: ``set screensize'' is obsolete. Use ``set height'' and
7789 ``set width'' instead.
7791 print address on/off: Print memory addresses in various command displays,
7792 such as stack traces and structure values. Gdb looks
7793 more ``symbolic'' if you turn this off; it looks more
7794 ``machine level'' with it on. Default is ON.
7796 print array on/off: Prettyprint arrays. New convenient format! Default
7799 print demangle on/off: Print C++ symbols in "source" form if on,
7802 print asm-demangle on/off: Same, for assembler level printouts
7805 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7808 * Support for Epoch Environment.
7810 The epoch environment is a version of Emacs v18 with windowing. One
7811 new command, ``inspect'', is identical to ``print'', except that if you
7812 are running in the epoch environment, the value is printed in its own
7816 * Support for Shared Libraries
7818 GDB can now debug programs and core files that use SunOS shared libraries.
7819 Symbols from a shared library cannot be referenced
7820 before the shared library has been linked with the program (this
7821 happens after you type ``run'' and before the function main() is entered).
7822 At any time after this linking (including when examining core files
7823 from dynamically linked programs), gdb reads the symbols from each
7824 shared library when you type the ``sharedlibrary'' command.
7825 It can be abbreviated ``share''.
7827 sharedlibrary REGEXP: Load shared object library symbols for files
7828 matching a unix regular expression. No argument
7829 indicates to load symbols for all shared libraries.
7831 info sharedlibrary: Status of loaded shared libraries.
7836 A watchpoint stops execution of a program whenever the value of an
7837 expression changes. Checking for this slows down execution
7838 tremendously whenever you are in the scope of the expression, but is
7839 quite useful for catching tough ``bit-spreader'' or pointer misuse
7840 problems. Some machines such as the 386 have hardware for doing this
7841 more quickly, and future versions of gdb will use this hardware.
7843 watch EXP: Set a watchpoint (breakpoint) for an expression.
7845 info watchpoints: Information about your watchpoints.
7847 delete N: Deletes watchpoint number N (same as breakpoints).
7848 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7849 enable N: Re-enables watchpoint number N (same as breakpoints).
7852 * C++ multiple inheritance
7854 When used with a GCC version 2 compiler, GDB supports multiple inheritance
7857 * C++ exception handling
7859 Gdb now supports limited C++ exception handling. Besides the existing
7860 ability to breakpoint on an exception handler, gdb can breakpoint on
7861 the raising of an exception (before the stack is peeled back to the
7864 catch FOO: If there is a FOO exception handler in the dynamic scope,
7865 set a breakpoint to catch exceptions which may be raised there.
7866 Multiple exceptions (``catch foo bar baz'') may be caught.
7868 info catch: Lists all exceptions which may be caught in the
7869 current stack frame.
7872 * Minor command changes
7874 The command ``call func (arg, arg, ...)'' now acts like the print
7875 command, except it does not print or save a value if the function's result
7876 is void. This is similar to dbx usage.
7878 The ``up'' and ``down'' commands now always print the frame they end up
7879 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7880 frames without printing.
7882 * New directory command
7884 'dir' now adds directories to the FRONT of the source search path.
7885 The path starts off empty. Source files that contain debug information
7886 about the directory in which they were compiled can be found even
7887 with an empty path; Sun CC and GCC include this information. If GDB can't
7888 find your source file in the current directory, type "dir .".
7890 * Configuring GDB for compilation
7892 For normal use, type ``./configure host''. See README or gdb.texinfo
7895 GDB now handles cross debugging. If you are remotely debugging between
7896 two different machines, type ``./configure host -target=targ''.
7897 Host is the machine where GDB will run; targ is the machine
7898 where the program that you are debugging will run.