1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 10
6 * Building GDB now requires GMP (The GNU Multiple Precision Arithmetic
11 ** '-break-insert --qualified' and '-dprintf-insert --qualified'
13 The MI -break-insert and -dprintf-insert commands now support a
14 new "--qualified" option that makes GDB interpret a specified
15 function name as a complete fully-qualified name. This is the
16 equivalent of the CLI's "break -qualified" and "dprintf
19 * GDB now supports core file debugging for x86_64 Cygwin programs.
21 * GDB will now look for the .gdbinit file in a config directory before
22 looking for ~/.gdbinit. The file is searched for in the following
23 locations: $XDG_CONFIG_HOME/gdb/gdbinit, $HOME/.config/gdb/gdbinit,
24 $HOME/.gdbinit. On Apple hosts the search order is instead:
25 $HOME/Library/Preferences/gdb/gdbinit, $HOME/.gdbinit.
27 * GDB now supports fixed point types which are described in DWARF
28 as base types with a fixed-point encoding. Additionally, support
29 for the DW_AT_GNU_numerator and DW_AT_GNU_denominator has also
32 For Ada, this allows support for fixed point types without requiring
33 the use of the GNAT encoding (based on information added to the type's
34 name following a GNAT-specific format).
40 Control the display of debug output about GDB's event loop.
42 maintenance flush symbol-cache
43 maintenance flush register-cache
44 These new commands are equivalent to the already existing commands
45 'maintenance flush-symbol-cache' and 'flushregs' respectively.
47 maintenance flush dcache
48 A new command to flush the dcache.
52 break [PROBE_MODIFIER] [LOCATION] [thread THREADNUM]
53 [-force-condition] [if CONDITION]
54 This command would previously refuse setting a breakpoint if the
55 CONDITION expression is invalid at a location. It now accepts and
56 defines the breakpoint if there is at least one location at which
57 the CONDITION is valid. The locations for which the CONDITION is
58 invalid, are automatically disabled. If CONDITION is invalid at all
59 of the locations, setting the breakpoint is still rejected. However,
60 the '-force-condition' flag can be used in this case for forcing GDB to
61 define the breakpoint, making all the current locations automatically
62 disabled. This may be useful if the user knows the condition will
63 become meaningful at a future location, e.g. due to a shared library
66 condition [-force] N COND
67 The behavior of this command is changed the same way for the 'break'
68 command as explained above. The '-force' flag can be used to force
69 GDB into defining the condition even when COND is invalid for all the
70 current locations of breakpoint N.
73 maintenance flush-symbol-cache
74 These commands are deprecated in favor of the new commands
75 'maintenance flush register-cache' and 'maintenance flush
76 symbol-cache' respectively.
78 set style version foreground COLOR
79 set style version background COLOR
80 set style version intensity VALUE
81 Control the styling of GDB's version number text.
84 When the ID parameter is omitted, then this command prints information
85 about the current inferior. When the ID parameter is present, the
86 behavior of the command is unchanged and have the inferior ID become
89 maintenance info sections
90 The ALLOBJ keyword has been replaced with an -all-objects command
91 line flag. It is now possible to filter which sections are printed
92 even when -all-objects is passed.
94 * Removed targets and native configurations
96 ARM Symbian arm*-*-symbianelf*
100 * There are new feature names for ARC targets: "org.gnu.gdb.arc.core"
101 and "org.gnu.gdb.arc.aux". The old names are still supported but
102 must be considered obsolete. They will be deprecated after some
105 * Help and apropos commands will now show the documentation of a
106 command only once, even if that command has one or more aliases.
107 These commands now show the command name, then all of its aliases,
108 and finally the description of the command.
110 * 'help aliases' now shows only the user defined aliases. GDB predefined
111 aliases are shown together with their aliased command.
113 * GDB now supports debuginfod, an HTTP server for distributing ELF/DWARF
114 debugging information as well as source code.
116 When built with debuginfod, GDB can automatically query debuginfod
117 servers for the separate debug files and source code of the executable
120 To build GDB with debuginfod, pass --with-debuginfod to configure (this
121 requires libdebuginfod, the debuginfod client library).
123 debuginfod is distributed with elfutils, starting with version 0.178.
125 You can get the latest version from https://sourceware.org/elfutils.
127 * Multi-target debugging support
129 GDB now supports debugging multiple target connections
130 simultaneously. For example, you can now have each inferior
131 connected to different remote servers running in different machines,
132 or have one inferior debugging a local native process, an inferior
133 debugging a core dump, etc.
135 This support is experimental and comes with some limitations -- you
136 can only resume multiple targets simultaneously if all targets
137 support non-stop mode, and all remote stubs or servers must support
138 the same set of remote protocol features exactly. See also "info
139 connections" and "add-inferior -no-connection" below, and "maint set
140 target-non-stop" in the user manual.
142 * New features in the GDB remote stub, GDBserver
144 ** GDBserver is now supported on ARC GNU/Linux.
146 ** GDBserver is now supported on RISC-V GNU/Linux.
148 ** GDBserver no longer supports these host triplets:
159 i[34567]86-*-mingw32ce*
161 * Debugging MS-Windows processes now sets $_exitsignal when the
162 inferior is terminated by a signal, instead of setting $_exitcode.
164 * Multithreaded symbol loading has now been enabled by default on systems
165 that support it (see entry for GDB 9, below), providing faster
166 performance for programs with many symbols.
168 * The $_siginfo convenience variable now also works on Windows targets,
169 and will display the EXCEPTION_RECORD of the last handled exception.
171 * TUI windows can now be arranged horizontally.
173 * The command history filename can now be set to the empty string
174 either using 'set history filename' or by setting 'GDBHISTFILE=' in
175 the environment. The effect of setting this filename to the empty
176 string is that GDB will not try to load any previous command
179 * On Windows targets, it is now possible to debug 32-bit programs with a
184 set exec-file-mismatch -- Set exec-file-mismatch handling (ask|warn|off).
185 show exec-file-mismatch -- Show exec-file-mismatch handling (ask|warn|off).
186 Set or show the option 'exec-file-mismatch'. When GDB attaches to a
187 running process, this new option indicates whether to detect
188 a mismatch between the current executable file loaded by GDB and the
189 executable file used to start the process. If 'ask', the default,
190 display a warning and ask the user whether to load the process
191 executable file; if 'warn', just display a warning; if 'off', don't
192 attempt to detect a mismatch.
194 tui new-layout NAME WINDOW WEIGHT [WINDOW WEIGHT]...
195 Define a new TUI layout, specifying its name and the windows that
198 maintenance print xml-tdesc [FILE]
199 Prints the current target description as an XML document. If the
200 optional FILE is provided (which is an XML target description) then
201 the target description is read from FILE into GDB, and then
204 maintenance print core-file-backed-mappings
205 Prints file-backed mappings loaded from a core file's note section.
206 Output is expected to be similar to that of "info proc mappings".
208 set debug fortran-array-slicing on|off
209 show debug fortran-array-slicing
210 Print debugging when taking slices of Fortran arrays.
212 set fortran repack-array-slices on|off
213 show fortran repack-array-slices
214 When taking slices from Fortran arrays and strings, if the slice is
215 non-contiguous within the original value then, when this option is
216 on, the new value will be repacked into a single contiguous value.
217 When this option is off, then the value returned will consist of a
218 descriptor that describes the slice within the memory of the
219 original parent value.
223 alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
224 The alias command can now specify default args for an alias.
225 GDB automatically prepends the alias default args to the argument list
226 provided explicitly by the user.
227 For example, to have a backtrace with full details, you can define
229 'alias bt_ALL = backtrace -entry-values both -frame-arg all
230 -past-main -past-entry -full'.
231 Alias default arguments can also use a set of nested 'with' commands,
232 e.g. 'alias pp10 = with print pretty -- with print elem 10 -- print'
233 defines the alias pp10 that will pretty print a maximum of 10 elements
234 of the given expression (if the expression is an array).
238 GNU/Linux/RISC-V (gdbserver) riscv*-*-linux*
243 ** gdb.register_window_type can be used to implement new TUI windows
246 ** Dynamic types can now be queried. gdb.Type has a new attribute,
247 "dynamic", and gdb.Type.sizeof can be None for a dynamic type. A
248 field of a dynamic type may have None for its "bitpos" attribute
251 ** Commands written in Python can be in the "TUI" help class by
252 registering with the new constant gdb.COMMAND_TUI.
254 ** New method gdb.PendingFrame.architecture () to retrieve the
255 architecture of the pending frame.
257 ** New gdb.Architecture.registers method that returns a
258 gdb.RegisterDescriptorIterator object, an iterator that returns
259 gdb.RegisterDescriptor objects. The new RegisterDescriptor is a
260 way to query the registers available for an architecture.
262 ** New gdb.Architecture.register_groups method that returns a
263 gdb.RegisterGroupIterator object, an iterator that returns
264 gdb.RegisterGroup objects. The new RegisterGroup is a way to
265 discover the available register groups.
269 ** GDB can now be built with GNU Guile 3.0 and 2.2 in addition to 2.0.
271 ** Procedures 'memory-port-read-buffer-size',
272 'set-memory-port-read-buffer-size!', 'memory-port-write-buffer-size',
273 and 'set-memory-port-write-buffer-size!' are deprecated. When
274 using Guile 2.2 and later, users who need to control the size of
275 a memory port's internal buffer can use the 'setvbuf' procedure.
279 * 'thread-exited' event is now available in the annotations interface.
281 * New built-in convenience variables $_gdb_major and $_gdb_minor
282 provide the GDB version. They are handy for conditionally using
283 features available only in or since specific GDB versions, in
284 scripts that should work error-free with many different versions,
285 such as in system-wide init files.
287 * New built-in convenience functions $_gdb_setting, $_gdb_setting_str,
288 $_gdb_maint_setting and $_gdb_maint_setting_str provide access to values
289 of the GDB settings and the GDB maintenance settings. They are handy
290 for changing the logic of user defined commands depending on the
291 current GDB settings.
293 * GDB now supports Thread Local Storage (TLS) variables on several
294 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
295 architectures require kernel changes. TLS is not yet supported for
296 amd64 and i386 process core dumps.
298 * Support for Pointer Authentication (PAC) on AArch64 Linux. Return
299 addresses that required unmasking are shown in the backtrace with the
302 * Two new convenience functions $_cimag and $_creal that extract the
303 imaginary and real parts respectively from complex numbers.
305 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
306 provide the exitcode or exit status of the shell commands launched by
307 GDB commands such as "shell", "pipe" and "make".
309 * The command define-prefix can now define user defined prefix commands.
310 User defined commands can now be defined using these user defined prefix
313 * Command names can now use the . character.
315 * The RX port now supports XML target descriptions.
317 * GDB now shows the Ada task names at more places, e.g. in task switching
320 * GDB can now be compiled with Python 3 on Windows.
322 * New convenience variable $_ada_exception holds the address of the
323 Ada exception being thrown. This is set by Ada-related catchpoints.
325 * GDB can now place breakpoints on nested functions and subroutines in
326 Fortran code. The '::' operator can be used between parent and
327 child scopes when placing breakpoints, for example:
329 (gdb) break outer_function::inner_function
331 The 'outer_function::' prefix is only needed if 'inner_function' is
332 not visible in the current scope.
334 * In addition to the system-wide gdbinit file, if configured with
335 --with-system-gdbinit-dir, GDB will now also load files in that directory
336 as system gdbinit files, unless the -nx or -n flag is provided. Files
337 with extensions .gdb, .py and .scm are supported as long as GDB was
338 compiled with support for that language.
340 * GDB now supports multithreaded symbol loading for higher performance.
341 This feature is still in testing, so it is disabled by default. You
342 can turn it on using 'maint set worker-threads unlimited'.
346 ** The gdb.Value type has a new method 'format_string' which returns a
347 string representing the value. The formatting is controlled by the
348 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
349 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
350 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
352 ** gdb.Type has a new property 'objfile' which returns the objfile the
355 ** The frame information printed by the python frame filtering code
356 is now consistent with what the 'backtrace' command prints when
357 there are no filters, or when the 'backtrace' '-no-filters' option
360 ** The new function gdb.lookup_static_symbol can be used to look up
361 symbols with static linkage.
363 ** The new function gdb.lookup_static_symbols can be used to look up
364 all static symbols with static linkage.
366 ** gdb.Objfile has new methods 'lookup_global_symbol' and
367 'lookup_static_symbol' to lookup a symbol from this objfile only.
369 ** gdb.Block now supports the dictionary syntax for accessing symbols in
370 this block (e.g. block['local_variable']).
374 | [COMMAND] | SHELL_COMMAND
375 | -d DELIM COMMAND DELIM SHELL_COMMAND
376 pipe [COMMAND] | SHELL_COMMAND
377 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
378 Executes COMMAND and sends its output to SHELL_COMMAND.
379 With no COMMAND, repeat the last executed command
380 and send its output to SHELL_COMMAND.
382 define-prefix COMMAND
383 Define or mark a command as a user-defined prefix command.
385 with SETTING [VALUE] [-- COMMAND]
386 w SETTING [VALUE] [-- COMMAND]
387 Temporarily set SETTING, run COMMAND, and restore SETTING.
388 Usage: with SETTING -- COMMAND
389 With no COMMAND, repeats the last executed command.
390 SETTING is any GDB setting you can change with the "set"
391 subcommands. For example, 'with language c -- print someobj'
392 temporarily switches to the C language in order to print someobj.
393 Settings can be combined: 'w lang c -- w print elements unlimited --
394 usercmd' switches to the C language and runs usercmd with no limit
395 of array elements to print.
397 maint with SETTING [VALUE] [-- COMMAND]
398 Like "with", but works with "maintenance set" settings.
400 set may-call-functions [on|off]
401 show may-call-functions
402 This controls whether GDB will attempt to call functions in
403 the program, such as with expressions in the print command. It
404 defaults to on. Calling functions in the program being debugged
405 can have undesired side effects. It is now possible to forbid
406 such function calls. If function calls are forbidden, GDB will throw
407 an error when a command (such as print expression) calls a function
410 set print finish [on|off]
412 This controls whether the `finish' command will display the value
413 that is returned by the current function. When `off', the value is
414 still entered into the value history, but it is not printed. The
419 Allows deeply nested structures to be simplified when printing by
420 replacing deeply nested parts (beyond the max-depth) with ellipses.
421 The default max-depth is 20, but this can be set to unlimited to get
422 the old behavior back.
424 set print raw-values [on|off]
425 show print raw-values
426 By default, GDB applies the enabled pretty printers when printing a
427 value. This allows to ignore the enabled pretty printers for a series
428 of commands. The default is 'off'.
430 set logging debugredirect [on|off]
431 By default, GDB debug output will go to both the terminal and the logfile.
432 Set if you want debug output to go only to the log file.
434 set style title foreground COLOR
435 set style title background COLOR
436 set style title intensity VALUE
437 Control the styling of titles.
439 set style highlight foreground COLOR
440 set style highlight background COLOR
441 set style highlight intensity VALUE
442 Control the styling of highlightings.
444 maint set worker-threads
445 maint show worker-threads
446 Control the number of worker threads that can be used by GDB. The
447 default is 0. "unlimited" lets GDB choose a number that is
448 reasonable. Currently worker threads are only used when demangling
449 the names of linker symbols.
451 set style tui-border foreground COLOR
452 set style tui-border background COLOR
453 Control the styling of TUI borders.
455 set style tui-active-border foreground COLOR
456 set style tui-active-border background COLOR
457 Control the styling of the active TUI border.
459 maint set test-settings KIND
460 maint show test-settings KIND
461 A set of commands used by the testsuite for exercising the settings
464 maint set tui-resize-message [on|off]
465 maint show tui-resize-message
466 Control whether GDB prints a message each time the terminal is
467 resized when in TUI mode. This is primarily useful for testing the
470 set print frame-info [short-location|location|location-and-address
471 |source-and-location|source-line|auto]
472 show print frame-info
473 This controls what frame information is printed by the commands printing
474 a frame. This setting will e.g. influence the behaviour of 'backtrace',
475 'frame', 'stepi'. The python frame filtering also respect this setting.
476 The 'backtrace' '-frame-info' option can override this global setting.
478 set tui compact-source
479 show tui compact-source
481 Enable the "compact" display mode for the TUI source window. The
482 compact display uses only as much space as is needed for the line
483 numbers in the current file, and only a single space to separate the
484 line numbers from the source.
486 info modules [-q] [REGEXP]
487 Return a list of Fortran modules matching REGEXP, or all modules if
490 info module functions [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
491 Return a list of functions within all modules, grouped by module.
492 The list of functions can be restricted with the optional regular
493 expressions. MODULE_REGEXP matches against the module name,
494 TYPE_REGEXP matches against the function type signature, and REGEXP
495 matches against the function name.
497 info module variables [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
498 Return a list of variables within all modules, grouped by module.
499 The list of variables can be restricted with the optional regular
500 expressions. MODULE_REGEXP matches against the module name,
501 TYPE_REGEXP matches against the variable type, and REGEXP matches
502 against the variable name.
504 set debug remote-packet-max-chars
505 show debug remote-packet-max-chars
506 Controls the number of characters to output in a remote packet when using
508 The default is 512 bytes.
511 Lists the target connections currently in use.
516 The "help" command uses the title style to enhance the
517 readibility of its output by styling the classes and
521 Similarly to "help", the "apropos" command also uses the
522 title style for the command names. "apropos" accepts now
523 a flag "-v" (verbose) to show the full documentation
524 of matching commands and to use the highlight style to mark
525 the documentation parts matching REGEXP.
529 The GDB printf and eval commands can now print C-style and Ada-style
530 string convenience variables without calling functions in the program.
531 This allows to do formatted printing of strings without having
532 a running inferior, or when debugging a core dump.
534 info sources [-dirname | -basename] [--] [REGEXP]
535 This command has now optional arguments to only print the files
536 whose names match REGEXP. The arguments -dirname and -basename
537 allow to restrict matching respectively to the dirname and basename
541 The "show style" and its subcommands are now styling
542 a style name in their output using its own style, to help
543 the user visualize the different styles.
545 set print frame-arguments
546 The new value 'presence' indicates to only indicate the presence of
547 arguments using ..., instead of printing argument names and values.
549 set print raw-frame-arguments
550 show print raw-frame-arguments
552 These commands replace the similarly-named "set/show print raw
553 frame-arguments" commands (now with a dash instead of a space). The
554 old commands are now deprecated and may be removed in a future
557 add-inferior [-no-connection]
558 The add-inferior command now supports a "-no-connection" flag that
559 makes the new inferior start with no target connection associated.
560 By default, the new inferior inherits the target connection of the
561 current inferior. See also "info connections".
564 This command's output now includes a new "Connection" column
565 indicating which target connection an inferior is bound to. See
566 "info connections" above.
568 maint test-options require-delimiter
569 maint test-options unknown-is-error
570 maint test-options unknown-is-operand
571 maint show test-options-completion-result
572 Commands used by the testsuite to validate the command options
575 focus, winheight, +, -, >, <
576 These commands are now case-sensitive.
578 * New command options, command completion
580 GDB now has a standard infrastructure to support dash-style command
581 options ('-OPT'). One benefit is that commands that use it can
582 easily support completion of command line arguments. Try "CMD
583 -[TAB]" or "help CMD" to find options supported by a command. Over
584 time, we intend to migrate most commands to this infrastructure. A
585 number of commands got support for new command options in this
588 ** The "print" and "compile print" commands now support a number of
589 options that allow overriding relevant global print settings as
590 set by "set print" subcommands:
594 -array-indexes [on|off]
595 -elements NUMBER|unlimited
600 -repeats NUMBER|unlimited
601 -static-members [on|off]
606 Note that because the "print"/"compile print" commands accept
607 arbitrary expressions which may look like options (including
608 abbreviations), if you specify any command option, then you must
609 use a double dash ("--") to mark the end of argument processing.
611 ** The "backtrace" command now supports a number of options that
612 allow overriding relevant global print settings as set by "set
613 backtrace" and "set print" subcommands:
615 -entry-values no|only|preferred|if-needed|both|compact|default
616 -frame-arguments all|scalars|none
617 -raw-frame-arguments [on|off]
618 -frame-info auto|source-line|location|source-and-location
619 |location-and-address|short-location
623 In addition, the full/no-filters/hide qualifiers are now also
624 exposed as command options too:
630 ** The "frame apply", "tfaas" and "faas" commands similarly now
631 support the following options:
636 ** The new "info sources" options -dirname and -basename options
637 are using the standard '-OPT' infrastructure.
639 All options above can also be abbreviated. The argument of boolean
640 (on/off) options can be 0/1 too, and also the argument is assumed
641 "on" if omitted. This allows writing compact command invocations,
644 (gdb) p -ra -p -o 0 -- *myptr
646 The above is equivalent to:
648 (gdb) print -raw-values -pretty -object off -- *myptr
650 ** The "info types" command now supports the '-q' flag to disable
651 printing of some header information in a similar fashion to "info
652 variables" and "info functions".
654 ** The "info variables", "info functions", and "whereis" commands
655 now take a '-n' flag that excludes non-debug symbols (symbols
656 from the symbol table, not from the debug info such as DWARF)
659 * Completion improvements
661 ** GDB can now complete the options of the "thread apply all" and
662 "taas" commands, and their "-ascending" option can now be
665 ** GDB can now complete the options of the "info threads", "info
666 functions", "info variables", "info locals", and "info args"
669 ** GDB can now complete the options of the "compile file" and
670 "compile code" commands. The "compile file" command now
671 completes on filenames.
673 ** GDB can now complete the backtrace command's
674 "full/no-filters/hide" qualifiers.
676 * In settings, you can now abbreviate "unlimited".
678 E.g., "set print elements u" is now equivalent to "set print
684 This lists all the possible completions for the rest of the line, if it
685 were to be given as a command itself. This is intended for use by MI
686 frontends in cases when separate CLI and MI channels cannot be used.
688 -catch-throw, -catch-rethrow, and -catch-catch
689 These can be used to catch C++ exceptions in a similar fashion to
690 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
692 -symbol-info-functions, -symbol-info-types, and -symbol-info-variables
693 These commands are the MI equivalent of the CLI commands 'info
694 functions', 'info types', and 'info variables' respectively.
696 -symbol-info-modules, this is the MI equivalent of the CLI 'info
699 -symbol-info-module-functions and -symbol-info-module-variables.
700 These commands are the MI equivalent of the CLI commands 'info
701 module functions' and 'info module variables'.
705 ** The default version of the MI interpreter is now 3 (-i=mi3).
707 ** The output of information about multi-location breakpoints (which is
708 syntactically incorrect in MI 2) has changed in MI 3. This affects
709 the following commands and events:
713 - =breakpoint-created
714 - =breakpoint-modified
716 The -fix-multi-location-breakpoint-output command can be used to enable
717 this behavior with previous MI versions.
719 ** Backtraces and frames include a new optional field addr_flags which is
720 given after the addr field. On AArch64 this contains PAC if the address
721 has been masked in the frame. On all other targets the field is not
726 The testsuite now creates the files gdb.cmd (containing the arguments
727 used to launch GDB) and gdb.in (containing all the commands sent to
728 GDB) in the output directory for each test script. Multiple invocations
729 are appended with .1, .2, .3 etc.
731 * Building GDB and GDBserver now requires GNU make >= 3.82.
733 Using another implementation of the make program or an earlier version of
734 GNU make to build GDB or GDBserver is not supported.
736 * Building GDB now requires GNU readline >= 7.0.
738 GDB now bundles GNU readline 8.0, but if you choose to use
739 --with-system-readline, only readline >= 7.0 can be used.
741 * The TUI SingleKey keymap is now named "SingleKey". This can be used
742 from .inputrc to bind keys in this keymap. This feature is only
743 available when gdb is built against GNU readline 8.0 or later.
745 * Removed targets and native configurations
747 GDB no longer supports debugging the Cell Broadband Engine. This includes
748 both debugging standalone Cell/B.E. SPU applications and integrated debugging
749 of Cell/B.E. applications that use both the PPU and SPU architectures.
755 * Removed targets and native configurations
757 Solaris 10 i?86-*-solaris2.10, x86_64-*-solaris2.10,
760 *** Changes in GDB 8.3
762 * GDB and GDBserver now support access to additional registers on
763 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
766 * GDB now has experimental support for the compilation and injection of
767 C++ source code into the inferior. This beta release does not include
768 support for several language features, such as templates, constructors,
771 This feature requires GCC 7.1 or higher built with libcp1.so
774 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
775 can be passed using the '[ADDRESS]:PORT' notation, or the regular
776 'ADDRESS:PORT' method.
778 * DWARF index cache: GDB can now automatically save indices of DWARF
779 symbols on disk to speed up further loading of the same binaries.
781 * Ada task switching is now supported on aarch64-elf targets when
782 debugging a program using the Ravenscar Profile. For more information,
783 see the "Tasking Support when using the Ravenscar Profile" section
784 in the GDB user manual.
786 * GDB in batch mode now exits with status 1 if the last command to be
789 * The RISC-V target now supports target descriptions.
791 * System call catchpoints now support system call aliases on FreeBSD.
792 When the ABI of a system call changes in FreeBSD, this is
793 implemented by leaving a compatibility system call using the old ABI
794 at the existing number and allocating a new system call number for
795 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
796 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
797 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
798 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
799 so that a system call catchpoint for the 'kevent' system call will
800 catch invocations of both the 'kevent' and 'freebsd11_kevent'
801 binaries. This ensures that 'kevent' system calls are caught for
802 binaries using either the old or new ABIs.
804 * Terminal styling is now available for the CLI and the TUI. GNU
805 Source Highlight can additionally be used to provide styling of
806 source code snippets. See the "set style" commands, below, for more
809 * Removed support for old demangling styles arm, edg, gnu, hp and
814 set debug compile-cplus-types
815 show debug compile-cplus-types
816 Control the display of debug output about type conversion in the
817 C++ compile feature. Commands have no effect while compiling
822 Control whether debug output about files/functions skipping is
825 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
826 Apply a command to some frames.
827 FLAG arguments allow to control what output to produce and how to handle
828 errors raised when applying COMMAND to a frame.
831 Apply a command to all threads (ignoring errors and empty output).
832 Shortcut for 'thread apply all -s COMMAND'.
835 Apply a command to all frames (ignoring errors and empty output).
836 Shortcut for 'frame apply all -s COMMAND'.
839 Apply a command to all frames of all threads (ignoring errors and empty
841 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
843 maint set dwarf unwinders (on|off)
844 maint show dwarf unwinders
845 Control whether DWARF unwinders can be used.
848 Display a list of open files for a process.
852 Changes to the "frame", "select-frame", and "info frame" CLI commands.
853 These commands all now take a frame specification which
854 is either a frame level, or one of the keywords 'level', 'address',
855 'function', or 'view' followed by a parameter. Selecting a frame by
856 address, or viewing a frame outside the current backtrace now
857 requires the use of a keyword. Selecting a frame by level is
858 unchanged. The MI comment "-stack-select-frame" is unchanged.
860 target remote FILENAME
861 target extended-remote FILENAME
862 If FILENAME is a Unix domain socket, GDB will attempt to connect
863 to this socket instead of opening FILENAME as a character device.
865 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
866 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
867 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
868 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
869 These commands can now print only the searched entities
870 matching the provided regexp(s), giving a condition
871 on the entity names or entity types. The flag -q disables
872 printing headers or informations messages.
878 These commands now determine the syntax for the shown entities
879 according to the language chosen by `set language'. In particular,
880 `set language auto' means to automatically choose the language of
883 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
884 The 'thread apply' command accepts new FLAG arguments.
885 FLAG arguments allow to control what output to produce and how to handle
886 errors raised when applying COMMAND to a thread.
888 set tui tab-width NCHARS
889 show tui tab-width NCHARS
890 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
892 set style enabled [on|off]
894 Enable or disable terminal styling. Styling is enabled by default
895 on most hosts, but disabled by default when in batch mode.
897 set style sources [on|off]
899 Enable or disable source code styling. Source code styling is
900 enabled by default, but only takes effect if styling in general is
901 enabled, and if GDB was linked with GNU Source Highlight.
903 set style filename foreground COLOR
904 set style filename background COLOR
905 set style filename intensity VALUE
906 Control the styling of file names.
908 set style function foreground COLOR
909 set style function background COLOR
910 set style function intensity VALUE
911 Control the styling of function names.
913 set style variable foreground COLOR
914 set style variable background COLOR
915 set style variable intensity VALUE
916 Control the styling of variable names.
918 set style address foreground COLOR
919 set style address background COLOR
920 set style address intensity VALUE
921 Control the styling of addresses.
925 ** The '-data-disassemble' MI command now accepts an '-a' option to
926 disassemble the whole function surrounding the given program
927 counter value or function name. Support for this feature can be
928 verified by using the "-list-features" command, which should
929 contain "data-disassemble-a-option".
931 ** Command responses and notifications that include a frame now include
932 the frame's architecture in a new "arch" attribute.
934 * New native configurations
936 GNU/Linux/RISC-V riscv*-*-linux*
937 FreeBSD/riscv riscv*-*-freebsd*
941 GNU/Linux/RISC-V riscv*-*-linux*
943 CSKY GNU/LINUX csky*-*-linux
944 FreeBSD/riscv riscv*-*-freebsd*
946 GNU/Linux/OpenRISC or1k*-*-linux*
950 GDB no longer supports native debugging on versions of MS-Windows
955 ** GDB no longer supports Python versions less than 2.6.
957 ** The gdb.Inferior type has a new 'progspace' property, which is the program
958 space associated to that inferior.
960 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
961 of objfiles associated to that program space.
963 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
964 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
967 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
968 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
969 correct and did not work properly.
971 ** The gdb.Value type has a new constructor, which is used to construct a
972 gdb.Value from a Python buffer object and a gdb.Type.
978 Enable or disable the undefined behavior sanitizer. This is
979 disabled by default, but passing --enable-ubsan=yes or
980 --enable-ubsan=auto to configure will enable it. Enabling this can
981 cause a performance penalty. The undefined behavior sanitizer was
982 first introduced in GCC 4.9.
984 *** Changes in GDB 8.2
986 * The 'set disassembler-options' command now supports specifying options
989 * The 'symbol-file' command now accepts an '-o' option to add a relative
990 offset to all sections.
992 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
993 a relative offset to all sections, but it allows to override the load
994 address of individual sections using '-s'.
996 * The 'add-symbol-file' command no longer requires the second argument
997 (address of the text section).
999 * The endianness used with the 'set endian auto' mode in the absence of
1000 an executable selected for debugging is now the last endianness chosen
1001 either by one of the 'set endian big' and 'set endian little' commands
1002 or by inferring from the last executable used, rather than the startup
1005 * The pager now allows a "c" response, meaning to disable the pager
1006 for the rest of the current command.
1008 * The commands 'info variables/functions/types' now show the source line
1009 numbers of symbol definitions when available.
1011 * 'info proc' now works on running processes on FreeBSD systems and core
1012 files created on FreeBSD systems.
1014 * C expressions can now use _Alignof, and C++ expressions can now use
1017 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
1018 the vector length while the process is running.
1024 Control display of debugging info regarding the FreeBSD native target.
1026 set|show varsize-limit
1027 This new setting allows the user to control the maximum size of Ada
1028 objects being printed when those objects have a variable type,
1029 instead of that maximum size being hardcoded to 65536 bytes.
1031 set|show record btrace cpu
1032 Controls the processor to be used for enabling errata workarounds for
1033 branch trace decode.
1035 maint check libthread-db
1036 Run integrity checks on the current inferior's thread debugging
1039 maint set check-libthread-db (on|off)
1040 maint show check-libthread-db
1041 Control whether to run integrity checks on inferior specific thread
1042 debugging libraries as they are loaded. The default is not to
1043 perform such checks.
1047 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
1049 ** The commands attached to a breakpoint can be set by assigning to
1050 the breakpoint's "commands" field.
1052 ** gdb.execute can now execute multi-line gdb commands.
1054 ** The new functions gdb.convenience_variable and
1055 gdb.set_convenience_variable can be used to get and set the value
1056 of convenience variables.
1058 ** A gdb.Parameter will no longer print the "set" help text on an
1059 ordinary "set"; instead by default a "set" will be silent unless
1060 the get_set_string method returns a non-empty string.
1064 RiscV ELF riscv*-*-elf
1066 * Removed targets and native configurations
1068 m88k running OpenBSD m88*-*-openbsd*
1069 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
1070 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
1071 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
1073 * Aarch64/Linux hardware watchpoints improvements
1075 Hardware watchpoints on unaligned addresses are now properly
1076 supported when running Linux kernel 4.10 or higher: read and access
1077 watchpoints are no longer spuriously missed, and all watchpoints
1078 lengths between 1 and 8 bytes are supported. On older kernels,
1079 watchpoints set on unaligned addresses are no longer missed, with
1080 the tradeoff that there is a possibility of false hits being
1085 --enable-codesign=CERT
1086 This can be used to invoke "codesign -s CERT" after building gdb.
1087 This option is useful on macOS, where code signing is required for
1088 gdb to work properly.
1090 --disable-gdbcli has been removed
1091 This is now silently accepted, but does nothing.
1093 *** Changes in GDB 8.1
1095 * GDB now supports dynamically creating arbitrary register groups specified
1096 in XML target descriptions. This allows for finer grain grouping of
1097 registers on systems with a large amount of registers.
1099 * The 'ptype' command now accepts a '/o' flag, which prints the
1100 offsets and sizes of fields in a struct, like the pahole(1) tool.
1102 * New "--readnever" command line option instructs GDB to not read each
1103 symbol file's symbolic debug information. This makes startup faster
1104 but at the expense of not being able to perform symbolic debugging.
1105 This option is intended for use cases where symbolic debugging will
1106 not be used, e.g., when you only need to dump the debuggee's core.
1108 * GDB now uses the GNU MPFR library, if available, to emulate target
1109 floating-point arithmetic during expression evaluation when the target
1110 uses different floating-point formats than the host. At least version
1111 3.1 of GNU MPFR is required.
1113 * GDB now supports access to the guarded-storage-control registers and the
1114 software-based guarded-storage broadcast control registers on IBM z14.
1116 * On Unix systems, GDB now supports transmitting environment variables
1117 that are to be set or unset to GDBserver. These variables will
1118 affect the environment to be passed to the remote inferior.
1120 To inform GDB of environment variables that are to be transmitted to
1121 GDBserver, use the "set environment" command. Only user set
1122 environment variables are sent to GDBserver.
1124 To inform GDB of environment variables that are to be unset before
1125 the remote inferior is started by the GDBserver, use the "unset
1126 environment" command.
1128 * Completion improvements
1130 ** GDB can now complete function parameters in linespecs and
1131 explicit locations without quoting. When setting breakpoints,
1132 quoting around functions names to help with TAB-completion is
1133 generally no longer necessary. For example, this now completes
1136 (gdb) b function(in[TAB]
1137 (gdb) b function(int)
1139 Related, GDB is no longer confused with completing functions in
1140 C++ anonymous namespaces:
1143 (gdb) b (anonymous namespace)::[TAB][TAB]
1144 (anonymous namespace)::a_function()
1145 (anonymous namespace)::b_function()
1147 ** GDB now has much improved linespec and explicit locations TAB
1148 completion support, that better understands what you're
1149 completing and offers better suggestions. For example, GDB no
1150 longer offers data symbols as possible completions when you're
1151 setting a breakpoint.
1153 ** GDB now TAB-completes label symbol names.
1155 ** The "complete" command now mimics TAB completion accurately.
1157 * New command line options (gcore)
1160 Dump all memory mappings.
1162 * Breakpoints on C++ functions are now set on all scopes by default
1164 By default, breakpoints on functions/methods are now interpreted as
1165 specifying all functions with the given name ignoring missing
1166 leading scopes (namespaces and classes).
1168 For example, assuming a C++ program with symbols named:
1173 both commands "break func()" and "break B::func()" set a breakpoint
1176 You can use the new flag "-qualified" to override this. This makes
1177 GDB interpret the specified function name as a complete
1178 fully-qualified name instead. For example, using the same C++
1179 program, the "break -q B::func" command sets a breakpoint on
1180 "B::func", only. A parameter has been added to the Python
1181 gdb.Breakpoint constructor to achieve the same result when creating
1182 a breakpoint from Python.
1184 * Breakpoints on functions marked with C++ ABI tags
1186 GDB can now set breakpoints on functions marked with C++ ABI tags
1187 (e.g., [abi:cxx11]). See here for a description of ABI tags:
1188 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
1190 Functions with a C++11 abi tag are demangled/displayed like this:
1192 function[abi:cxx11](int)
1195 You can now set a breakpoint on such functions simply as if they had
1198 (gdb) b function(int)
1200 Or if you need to disambiguate between tags, like:
1202 (gdb) b function[abi:other_tag](int)
1204 Tab completion was adjusted accordingly as well.
1208 ** New events gdb.new_inferior, gdb.inferior_deleted, and
1209 gdb.new_thread are emitted. See the manual for further
1210 description of these.
1212 ** A new function, "gdb.rbreak" has been added to the Python API.
1213 This function allows the setting of a large number of breakpoints
1214 via a regex pattern in Python. See the manual for further details.
1216 ** Python breakpoints can now accept explicit locations. See the
1217 manual for a further description of this feature.
1220 * New features in the GDB remote stub, GDBserver
1222 ** GDBserver is now able to start inferior processes with a
1223 specified initial working directory.
1225 The user can set the desired working directory to be used from
1226 GDB using the new "set cwd" command.
1228 ** New "--selftest" command line option runs some GDBserver self
1229 tests. These self tests are disabled in releases.
1231 ** On Unix systems, GDBserver now does globbing expansion and variable
1232 substitution in inferior command line arguments.
1234 This is done by starting inferiors using a shell, like GDB does.
1235 See "set startup-with-shell" in the user manual for how to disable
1236 this from GDB when using "target extended-remote". When using
1237 "target remote", you can disable the startup with shell by using the
1238 new "--no-startup-with-shell" GDBserver command line option.
1240 ** On Unix systems, GDBserver now supports receiving environment
1241 variables that are to be set or unset from GDB. These variables
1242 will affect the environment to be passed to the inferior.
1244 * When catching an Ada exception raised with a message, GDB now prints
1245 the message in the catchpoint hit notification. In GDB/MI mode, that
1246 information is provided as an extra field named "exception-message"
1247 in the *stopped notification.
1249 * Trait objects can now be inspected When debugging Rust code. This
1250 requires compiler support which will appear in Rust 1.24.
1252 * New remote packets
1254 QEnvironmentHexEncoded
1255 Inform GDBserver of an environment variable that is to be passed to
1256 the inferior when starting it.
1259 Inform GDBserver of an environment variable that is to be unset
1260 before starting the remote inferior.
1263 Inform GDBserver that the environment should be reset (i.e.,
1264 user-set environment variables should be unset).
1267 Indicates whether the inferior must be started with a shell or not.
1270 Tell GDBserver that the inferior to be started should use a specific
1273 * The "maintenance print c-tdesc" command now takes an optional
1274 argument which is the file name of XML target description.
1276 * The "maintenance selftest" command now takes an optional argument to
1277 filter the tests to be run.
1279 * The "enable", and "disable" commands now accept a range of
1280 breakpoint locations, e.g. "enable 1.3-5".
1285 Set and show the current working directory for the inferior.
1287 set|show compile-gcc
1288 Set and show compilation command used for compiling and injecting code
1289 with the 'compile' commands.
1291 set debug separate-debug-file
1292 show debug separate-debug-file
1293 Control the display of debug output about separate debug file search.
1295 set dump-excluded-mappings
1296 show dump-excluded-mappings
1297 Control whether mappings marked with the VM_DONTDUMP flag should be
1298 dumped when generating a core file.
1300 maint info selftests
1301 List the registered selftests.
1304 Start the debugged program stopping at the first instruction.
1307 Control display of debugging messages related to OpenRISC targets.
1309 set|show print type nested-type-limit
1310 Set and show the limit of nesting level for nested types that the
1311 type printer will show.
1313 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
1316 * Safer/improved support for debugging with no debug info
1318 GDB no longer assumes functions with no debug information return
1321 This means that GDB now refuses to call such functions unless you
1322 tell it the function's type, by either casting the call to the
1323 declared return type, or by casting the function to a function
1324 pointer of the right type, and calling that:
1326 (gdb) p getenv ("PATH")
1327 'getenv' has unknown return type; cast the call to its declared return type
1328 (gdb) p (char *) getenv ("PATH")
1329 $1 = 0x7fffffffe "/usr/local/bin:/"...
1330 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
1331 $2 = 0x7fffffffe "/usr/local/bin:/"...
1333 Similarly, GDB no longer assumes that global variables with no debug
1334 info have type 'int', and refuses to print the variable's value
1335 unless you tell it the variable's type:
1338 'var' has unknown type; cast it to its declared type
1342 * New native configurations
1344 FreeBSD/aarch64 aarch64*-*-freebsd*
1345 FreeBSD/arm arm*-*-freebsd*
1349 FreeBSD/aarch64 aarch64*-*-freebsd*
1350 FreeBSD/arm arm*-*-freebsd*
1351 OpenRISC ELF or1k*-*-elf
1353 * Removed targets and native configurations
1355 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
1357 *** Changes in GDB 8.0
1359 * GDB now supports access to the PKU register on GNU/Linux. The register is
1360 added by the Memory Protection Keys for Userspace feature which will be
1361 available in future Intel CPUs.
1363 * GDB now supports C++11 rvalue references.
1367 ** New functions to start, stop and access a running btrace recording.
1368 ** Rvalue references are now supported in gdb.Type.
1370 * GDB now supports recording and replaying rdrand and rdseed Intel 64
1373 * Building GDB and GDBserver now requires a C++11 compiler.
1375 For example, GCC 4.8 or later.
1377 It is no longer possible to build GDB or GDBserver with a C
1378 compiler. The --disable-build-with-cxx configure option has been
1381 * Building GDB and GDBserver now requires GNU make >= 3.81.
1383 It is no longer supported to build GDB or GDBserver with another
1384 implementation of the make program or an earlier version of GNU make.
1386 * Native debugging on MS-Windows supports command-line redirection
1388 Command-line arguments used for starting programs on MS-Windows can
1389 now include redirection symbols supported by native Windows shells,
1390 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
1391 as "run", "start", and "set args", as well as the corresponding MI
1394 * Support for thread names on MS-Windows.
1396 GDB now catches and handles the special exception that programs
1397 running on MS-Windows use to assign names to threads in the
1400 * Support for Java programs compiled with gcj has been removed.
1402 * User commands now accept an unlimited number of arguments.
1403 Previously, only up to 10 was accepted.
1405 * The "eval" command now expands user-defined command arguments.
1407 This makes it easier to process a variable number of arguments:
1412 eval "print $arg%d", $i
1417 * Target descriptions can now describe registers for sparc32 and sparc64.
1419 * GDB now supports DWARF version 5 (debug information format).
1420 Its .debug_names index is not yet supported.
1422 * New native configurations
1424 FreeBSD/mips mips*-*-freebsd
1428 Synopsys ARC arc*-*-elf32
1429 FreeBSD/mips mips*-*-freebsd
1431 * Removed targets and native configurations
1433 Alpha running FreeBSD alpha*-*-freebsd*
1434 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
1439 Erases all the flash memory regions reported by the target.
1441 maint print arc arc-instruction address
1442 Print internal disassembler information about instruction at a given address.
1446 set disassembler-options
1447 show disassembler-options
1448 Controls the passing of target specific information to the disassembler.
1449 If it is necessary to specify more than one disassembler option then
1450 multiple options can be placed together into a comma separated list.
1451 The default value is the empty string. Currently, the only supported
1452 targets are ARM, PowerPC and S/390.
1457 Erases all the flash memory regions reported by the target. This is
1458 equivalent to the CLI command flash-erase.
1460 -file-list-shared-libraries
1461 List the shared libraries in the program. This is
1462 equivalent to the CLI command "info shared".
1465 Catchpoints stopping the program when Ada exceptions are
1466 handled. This is equivalent to the CLI command "catch handlers".
1468 *** Changes in GDB 7.12
1470 * GDB and GDBserver now build with a C++ compiler by default.
1472 The --enable-build-with-cxx configure option is now enabled by
1473 default. One must now explicitly configure with
1474 --disable-build-with-cxx in order to build with a C compiler. This
1475 option will be removed in a future release.
1477 * GDBserver now supports recording btrace without maintaining an active
1480 * GDB now supports a negative repeat count in the 'x' command to examine
1481 memory backward from the given address. For example:
1484 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
1485 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
1486 (gdb) x/-5i 0x0000000000400580
1487 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
1488 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
1489 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
1490 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
1491 0x40057b <main(int, char**)+25>:
1492 callq 0x400536 <Func1(int, char const*)>
1494 * Fortran: Support structures with fields of dynamic types and
1495 arrays of dynamic types.
1497 * The symbol dumping maintenance commands have new syntax.
1498 maint print symbols [-pc address] [--] [filename]
1499 maint print symbols [-objfile objfile] [-source source] [--] [filename]
1500 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
1501 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
1502 maint print msymbols [-objfile objfile] [--] [filename]
1504 * GDB now supports multibit bitfields and enums in target register
1507 * New Python-based convenience function $_as_string(val), which returns
1508 the textual representation of a value. This function is especially
1509 useful to obtain the text label of an enum value.
1511 * Intel MPX bound violation handling.
1513 Segmentation faults caused by a Intel MPX boundary violation
1514 now display the kind of violation (upper or lower), the memory
1515 address accessed and the memory bounds, along with the usual
1516 signal received and code location.
1520 Program received signal SIGSEGV, Segmentation fault
1521 Upper bound violation while accessing address 0x7fffffffc3b3
1522 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
1523 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
1525 * Rust language support.
1526 GDB now supports debugging programs written in the Rust programming
1527 language. See https://www.rust-lang.org/ for more information about
1530 * Support for running interpreters on specified input/output devices
1532 GDB now supports a new mechanism that allows frontends to provide
1533 fully featured GDB console views, as a better alternative to
1534 building such views on top of the "-interpreter-exec console"
1535 command. See the new "new-ui" command below. With that command,
1536 frontends can now start GDB in the traditional command-line mode
1537 running in an embedded terminal emulator widget, and create a
1538 separate MI interpreter running on a specified i/o device. In this
1539 way, GDB handles line editing, history, tab completion, etc. in the
1540 console all by itself, and the GUI uses the separate MI interpreter
1541 for its own control and synchronization, invisible to the command
1544 * The "catch syscall" command catches groups of related syscalls.
1546 The "catch syscall" command now supports catching a group of related
1547 syscalls using the 'group:' or 'g:' prefix.
1552 skip -gfile file-glob-pattern
1553 skip -function function
1554 skip -rfunction regular-expression
1555 A generalized form of the skip command, with new support for
1556 glob-style file names and regular expressions for function names.
1557 Additionally, a file spec and a function spec may now be combined.
1559 maint info line-table REGEXP
1560 Display the contents of GDB's internal line table data structure.
1563 Run any GDB unit tests that were compiled in.
1566 Start a new user interface instance running INTERP as interpreter,
1567 using the TTY file for input/output.
1571 ** gdb.Breakpoint objects have a new attribute "pending", which
1572 indicates whether the breakpoint is pending.
1573 ** Three new breakpoint-related events have been added:
1574 gdb.breakpoint_created, gdb.breakpoint_modified, and
1575 gdb.breakpoint_deleted.
1577 signal-event EVENTID
1578 Signal ("set") the given MS-Windows event object. This is used in
1579 conjunction with the Windows JIT debugging (AeDebug) support, where
1580 the OS suspends a crashing process until a debugger can attach to
1581 it. Resuming the crashing process, in order to debug it, is done by
1582 signalling an event.
1584 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
1585 was added in GDBserver, including JIT compiling fast tracepoint's
1586 conditional expression bytecode into native code.
1588 * Support for various remote target protocols and ROM monitors has
1591 target m32rsdi Remote M32R debugging over SDI
1592 target mips MIPS remote debugging protocol
1593 target pmon PMON ROM monitor
1594 target ddb NEC's DDB variant of PMON for Vr4300
1595 target rockhopper NEC RockHopper variant of PMON
1596 target lsi LSI variant of PMO
1598 * Support for tracepoints and fast tracepoints on powerpc-linux,
1599 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
1600 including JIT compiling fast tracepoint's conditional expression
1601 bytecode into native code.
1603 * MI async record =record-started now includes the method and format used for
1604 recording. For example:
1606 =record-started,thread-group="i1",method="btrace",format="bts"
1608 * MI async record =thread-selected now includes the frame field. For example:
1610 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
1614 Andes NDS32 nds32*-*-elf
1616 *** Changes in GDB 7.11
1618 * GDB now supports debugging kernel-based threads on FreeBSD.
1620 * Per-inferior thread numbers
1622 Thread numbers are now per inferior instead of global. If you're
1623 debugging multiple inferiors, GDB displays thread IDs using a
1624 qualified INF_NUM.THR_NUM form. For example:
1628 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
1629 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1630 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1631 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1633 As consequence, thread numbers as visible in the $_thread
1634 convenience variable and in Python's InferiorThread.num attribute
1635 are no longer unique between inferiors.
1637 GDB now maintains a second thread ID per thread, referred to as the
1638 global thread ID, which is the new equivalent of thread numbers in
1639 previous releases. See also $_gthread below.
1641 For backwards compatibility, MI's thread IDs always refer to global
1644 * Commands that accept thread IDs now accept the qualified
1645 INF_NUM.THR_NUM form as well. For example:
1648 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1651 * In commands that accept a list of thread IDs, you can now refer to
1652 all threads of an inferior using a star wildcard. GDB accepts
1653 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1654 refer to all threads of the current inferior. For example, "info
1657 * You can use "info threads -gid" to display the global thread ID of
1660 * The new convenience variable $_gthread holds the global number of
1663 * The new convenience variable $_inferior holds the number of the
1666 * GDB now displays the ID and name of the thread that hit a breakpoint
1667 or received a signal, if your program is multi-threaded. For
1670 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1671 Thread 1 "main" received signal SIGINT, Interrupt.
1673 * Record btrace now supports non-stop mode.
1675 * Support for tracepoints on aarch64-linux was added in GDBserver.
1677 * The 'record instruction-history' command now indicates speculative execution
1678 when using the Intel Processor Trace recording format.
1680 * GDB now allows users to specify explicit locations, bypassing
1681 the linespec parser. This feature is also available to GDB/MI
1684 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1685 GDB now is able to debug both AArch64 applications and ARM applications
1688 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1689 including JIT compiling fast tracepoint's conditional expression bytecode
1692 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1694 * "info threads", "info inferiors", "info display", "info checkpoints"
1695 and "maint info program-spaces" now list the corresponding items in
1696 ascending ID order, for consistency with all other "info" commands.
1698 * In Ada, the overloads selection menu has been enhanced to display the
1699 parameter types and the return types for the matching overloaded subprograms.
1703 maint set target-non-stop (on|off|auto)
1704 maint show target-non-stop
1705 Control whether GDB targets always operate in non-stop mode even if
1706 "set non-stop" is "off". The default is "auto", meaning non-stop
1707 mode is enabled if supported by the target.
1709 maint set bfd-sharing
1710 maint show bfd-sharing
1711 Control the reuse of bfd objects.
1714 show debug bfd-cache
1715 Control display of debugging info regarding bfd caching.
1719 Control display of debugging info regarding FreeBSD threads.
1721 set remote multiprocess-extensions-packet
1722 show remote multiprocess-extensions-packet
1723 Set/show the use of the remote protocol multiprocess extensions.
1725 set remote thread-events
1726 show remote thread-events
1727 Set/show the use of thread create/exit events.
1729 set ada print-signatures on|off
1730 show ada print-signatures"
1731 Control whether parameter types and return types are displayed in overloads
1732 selection menus. It is activated (@code{on}) by default.
1736 Controls the maximum size of memory, in bytes, that GDB will
1737 allocate for value contents. Prevents incorrect programs from
1738 causing GDB to allocate overly large buffers. Default is 64k.
1740 * The "disassemble" command accepts a new modifier: /s.
1741 It prints mixed source+disassembly like /m with two differences:
1742 - disassembled instructions are now printed in program order, and
1743 - and source for all relevant files is now printed.
1744 The "/m" option is now considered deprecated: its "source-centric"
1745 output hasn't proved useful in practice.
1747 * The "record instruction-history" command accepts a new modifier: /s.
1748 It behaves exactly like /m and prints mixed source+disassembly.
1750 * The "set scheduler-locking" command supports a new mode "replay".
1751 It behaves like "off" in record mode and like "on" in replay mode.
1753 * Support for various ROM monitors has been removed:
1755 target dbug dBUG ROM monitor for Motorola ColdFire
1756 target picobug Motorola picobug monitor
1757 target dink32 DINK32 ROM monitor for PowerPC
1758 target m32r Renesas M32R/D ROM monitor
1759 target mon2000 mon2000 ROM monitor
1760 target ppcbug PPCBUG ROM monitor for PowerPC
1762 * Support for reading/writing memory and extracting values on architectures
1763 whose memory is addressable in units of any integral multiple of 8 bits.
1766 Allows to break when an Ada exception is handled.
1768 * New remote packets
1771 Indicates that an exec system call was executed.
1773 exec-events feature in qSupported
1774 The qSupported packet allows GDB to request support for exec
1775 events using the new 'gdbfeature' exec-event, and the qSupported
1776 response can contain the corresponding 'stubfeature'. Set and
1777 show commands can be used to display whether these features are enabled.
1780 Equivalent to interrupting with the ^C character, but works in
1783 thread created stop reason (T05 create:...)
1784 Indicates that the thread was just created and is stopped at entry.
1786 thread exit stop reply (w exitcode;tid)
1787 Indicates that the thread has terminated.
1790 Enables/disables thread create and exit event reporting. For
1791 example, this is used in non-stop mode when GDB stops a set of
1792 threads and synchronously waits for the their corresponding stop
1793 replies. Without exit events, if one of the threads exits, GDB
1794 would hang forever not knowing that it should no longer expect a
1795 stop for that same thread.
1798 Indicates that there are no resumed threads left in the target (all
1799 threads are stopped). The remote stub reports support for this stop
1800 reply to GDB's qSupported query.
1803 Enables/disables catching syscalls from the inferior process.
1804 The remote stub reports support for this packet to GDB's qSupported query.
1806 syscall_entry stop reason
1807 Indicates that a syscall was just called.
1809 syscall_return stop reason
1810 Indicates that a syscall just returned.
1812 * Extended-remote exec events
1814 ** GDB now has support for exec events on extended-remote Linux targets.
1815 For such targets with Linux kernels 2.5.46 and later, this enables
1816 follow-exec-mode and exec catchpoints.
1818 set remote exec-event-feature-packet
1819 show remote exec-event-feature-packet
1820 Set/show the use of the remote exec event feature.
1822 * Thread names in remote protocol
1824 The reply to qXfer:threads:read may now include a name attribute for each
1827 * Target remote mode fork and exec events
1829 ** GDB now has support for fork and exec events on target remote mode
1830 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1831 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1832 fork and exec catchpoints.
1834 * Remote syscall events
1836 ** GDB now has support for catch syscall on remote Linux targets,
1837 currently enabled on x86/x86_64 architectures.
1839 set remote catch-syscall-packet
1840 show remote catch-syscall-packet
1841 Set/show the use of the remote catch syscall feature.
1845 ** The -var-set-format command now accepts the zero-hexadecimal
1846 format. It outputs data in hexadecimal format with zero-padding on the
1851 ** gdb.InferiorThread objects have a new attribute "global_num",
1852 which refers to the thread's global thread ID. The existing
1853 "num" attribute now refers to the thread's per-inferior number.
1854 See "Per-inferior thread numbers" above.
1855 ** gdb.InferiorThread objects have a new attribute "inferior", which
1856 is the Inferior object the thread belongs to.
1858 *** Changes in GDB 7.10
1860 * Support for process record-replay and reverse debugging on aarch64*-linux*
1861 targets has been added. GDB now supports recording of A64 instruction set
1862 including advance SIMD instructions.
1864 * Support for Sun's version of the "stabs" debug file format has been removed.
1866 * GDB now honors the content of the file /proc/PID/coredump_filter
1867 (PID is the process ID) on GNU/Linux systems. This file can be used
1868 to specify the types of memory mappings that will be included in a
1869 corefile. For more information, please refer to the manual page of
1870 "core(5)". GDB also has a new command: "set use-coredump-filter
1871 on|off". It allows to set whether GDB will read the content of the
1872 /proc/PID/coredump_filter file when generating a corefile.
1874 * The "info os" command on GNU/Linux can now display information on
1876 "info os cpus" Listing of all cpus/cores on the system
1878 * GDB has two new commands: "set serial parity odd|even|none" and
1879 "show serial parity". These allows to set or show parity for the
1882 * The "info source" command now displays the producer string if it was
1883 present in the debug info. This typically includes the compiler version
1884 and may include things like its command line arguments.
1886 * The "info dll", an alias of the "info sharedlibrary" command,
1887 is now available on all platforms.
1889 * Directory names supplied to the "set sysroot" commands may be
1890 prefixed with "target:" to tell GDB to access shared libraries from
1891 the target system, be it local or remote. This replaces the prefix
1892 "remote:". The default sysroot has been changed from "" to
1893 "target:". "remote:" is automatically converted to "target:" for
1894 backward compatibility.
1896 * The system root specified by "set sysroot" will be prepended to the
1897 filename of the main executable (if reported to GDB as absolute by
1898 the operating system) when starting processes remotely, and when
1899 attaching to already-running local or remote processes.
1901 * GDB now supports automatic location and retrieval of executable
1902 files from remote targets. Remote debugging can now be initiated
1903 using only a "target remote" or "target extended-remote" command
1904 (no "set sysroot" or "file" commands are required). See "New remote
1907 * The "dump" command now supports verilog hex format.
1909 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
1911 * On GNU/Linux, GDB and gdbserver are now able to access executable
1912 and shared library files without a "set sysroot" command when
1913 attaching to processes running in different mount namespaces from
1914 the debugger. This makes it possible to attach to processes in
1915 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
1916 See "New remote packets" below.
1918 * The "tui reg" command now provides completion for all of the
1919 available register groups, including target specific groups.
1921 * The HISTSIZE environment variable is no longer read when determining
1922 the size of GDB's command history. GDB now instead reads the dedicated
1923 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
1924 disables truncation of command history. Non-numeric values of GDBHISTSIZE
1929 ** Memory ports can now be unbuffered.
1933 ** gdb.Objfile objects have a new attribute "username",
1934 which is the name of the objfile as specified by the user,
1935 without, for example, resolving symlinks.
1936 ** You can now write frame unwinders in Python.
1937 ** gdb.Type objects have a new method "optimized_out",
1938 returning optimized out gdb.Value instance of this type.
1939 ** gdb.Value objects have new methods "reference_value" and
1940 "const_value" which return a reference to the value and a
1941 "const" version of the value respectively.
1945 maint print symbol-cache
1946 Print the contents of the symbol cache.
1948 maint print symbol-cache-statistics
1949 Print statistics of symbol cache usage.
1951 maint flush-symbol-cache
1952 Flush the contents of the symbol cache.
1956 Start branch trace recording using Branch Trace Store (BTS) format.
1959 Evaluate expression by using the compiler and print result.
1963 Explicit commands for enabling and disabling tui mode.
1966 set mpx bound on i386 and amd64
1967 Support for bound table investigation on Intel MPX enabled applications.
1971 Start branch trace recording using Intel Processor Trace format.
1974 Print information about branch tracing internals.
1976 maint btrace packet-history
1977 Print the raw branch tracing data.
1979 maint btrace clear-packet-history
1980 Discard the stored raw branch tracing data.
1983 Discard all branch tracing data. It will be fetched and processed
1984 anew by the next "record" command.
1989 Renamed from "set debug dwarf2-die".
1990 show debug dwarf-die
1991 Renamed from "show debug dwarf2-die".
1993 set debug dwarf-read
1994 Renamed from "set debug dwarf2-read".
1995 show debug dwarf-read
1996 Renamed from "show debug dwarf2-read".
1998 maint set dwarf always-disassemble
1999 Renamed from "maint set dwarf2 always-disassemble".
2000 maint show dwarf always-disassemble
2001 Renamed from "maint show dwarf2 always-disassemble".
2003 maint set dwarf max-cache-age
2004 Renamed from "maint set dwarf2 max-cache-age".
2005 maint show dwarf max-cache-age
2006 Renamed from "maint show dwarf2 max-cache-age".
2008 set debug dwarf-line
2009 show debug dwarf-line
2010 Control display of debugging info regarding DWARF line processing.
2013 show max-completions
2014 Set the maximum number of candidates to be considered during
2015 completion. The default value is 200. This limit allows GDB
2016 to avoid generating large completion lists, the computation of
2017 which can cause the debugger to become temporarily unresponsive.
2019 set history remove-duplicates
2020 show history remove-duplicates
2021 Control the removal of duplicate history entries.
2023 maint set symbol-cache-size
2024 maint show symbol-cache-size
2025 Control the size of the symbol cache.
2027 set|show record btrace bts buffer-size
2028 Set and show the size of the ring buffer used for branch tracing in
2030 The obtained size may differ from the requested size. Use "info
2031 record" to see the obtained buffer size.
2033 set debug linux-namespaces
2034 show debug linux-namespaces
2035 Control display of debugging info regarding Linux namespaces.
2037 set|show record btrace pt buffer-size
2038 Set and show the size of the ring buffer used for branch tracing in
2039 Intel Processor Trace format.
2040 The obtained size may differ from the requested size. Use "info
2041 record" to see the obtained buffer size.
2043 maint set|show btrace pt skip-pad
2044 Set and show whether PAD packets are skipped when computing the
2047 * The command 'thread apply all' can now support new option '-ascending'
2048 to call its specified command for all threads in ascending order.
2050 * Python/Guile scripting
2052 ** GDB now supports auto-loading of Python/Guile scripts contained in the
2053 special section named `.debug_gdb_scripts'.
2055 * New remote packets
2057 qXfer:btrace-conf:read
2058 Return the branch trace configuration for the current thread.
2060 Qbtrace-conf:bts:size
2061 Set the requested ring buffer size for branch tracing in BTS format.
2064 Enable Intel Processor Trace-based branch tracing for the current
2065 process. The remote stub reports support for this packet to GDB's
2068 Qbtrace-conf:pt:size
2069 Set the requested ring buffer size for branch tracing in Intel Processor
2073 Indicates a memory breakpoint instruction was executed, irrespective
2074 of whether it was GDB that planted the breakpoint or the breakpoint
2075 is hardcoded in the program. This is required for correct non-stop
2079 Indicates the target stopped for a hardware breakpoint. This is
2080 required for correct non-stop mode operation.
2083 Return information about files on the remote system.
2085 qXfer:exec-file:read
2086 Return the full absolute name of the file that was executed to
2087 create a process running on the remote system.
2090 Select the filesystem on which vFile: operations with filename
2091 arguments will operate. This is required for GDB to be able to
2092 access files on remote targets where the remote stub does not
2093 share a common filesystem with the inferior(s).
2096 Indicates that a fork system call was executed.
2099 Indicates that a vfork system call was executed.
2101 vforkdone stop reason
2102 Indicates that a vfork child of the specified process has executed
2103 an exec or exit, allowing the vfork parent to resume execution.
2105 fork-events and vfork-events features in qSupported
2106 The qSupported packet allows GDB to request support for fork and
2107 vfork events using new 'gdbfeatures' fork-events and vfork-events,
2108 and the qSupported response can contain the corresponding
2109 'stubfeatures'. Set and show commands can be used to display
2110 whether these features are enabled.
2112 * Extended-remote fork events
2114 ** GDB now has support for fork events on extended-remote Linux
2115 targets. For targets with Linux kernels 2.5.60 and later, this
2116 enables follow-fork-mode and detach-on-fork for both fork and
2117 vfork, as well as fork and vfork catchpoints.
2119 * The info record command now shows the recording format and the
2120 branch tracing configuration for the current thread when using
2121 the btrace record target.
2122 For the BTS format, it shows the ring buffer size.
2124 * GDB now has support for DTrace USDT (Userland Static Defined
2125 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
2127 * GDB now supports access to vector registers on S/390 GNU/Linux
2130 * Removed command line options
2132 -xdb HP-UX XDB compatibility mode.
2134 * Removed targets and native configurations
2136 HP/PA running HP-UX hppa*-*-hpux*
2137 Itanium running HP-UX ia64-*-hpux*
2139 * New configure options
2142 This configure option allows the user to build GDB with support for
2143 Intel Processor Trace (default: auto). This requires libipt.
2145 --with-libipt-prefix=PATH
2146 Specify the path to the version of libipt that GDB should use.
2147 $PATH/include should contain the intel-pt.h header and
2148 $PATH/lib should contain the libipt.so library.
2150 *** Changes in GDB 7.9.1
2154 ** Xmethods can now specify a result type.
2156 *** Changes in GDB 7.9
2158 * GDB now supports hardware watchpoints on x86 GNU Hurd.
2162 ** You can now access frame registers from Python scripts.
2163 ** New attribute 'producer' for gdb.Symtab objects.
2164 ** gdb.Objfile objects have a new attribute "progspace",
2165 which is the gdb.Progspace object of the containing program space.
2166 ** gdb.Objfile objects have a new attribute "owner".
2167 ** gdb.Objfile objects have a new attribute "build_id",
2168 which is the build ID generated when the file was built.
2169 ** gdb.Objfile objects have a new method "add_separate_debug_file".
2170 ** A new event "gdb.clear_objfiles" has been added, triggered when
2171 selecting a new file to debug.
2172 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
2173 ** New function gdb.lookup_objfile.
2175 New events which are triggered when GDB modifies the state of the
2178 ** gdb.events.inferior_call_pre: Function call is about to be made.
2179 ** gdb.events.inferior_call_post: Function call has just been made.
2180 ** gdb.events.memory_changed: A memory location has been altered.
2181 ** gdb.events.register_changed: A register has been altered.
2183 * New Python-based convenience functions:
2185 ** $_caller_is(name [, number_of_frames])
2186 ** $_caller_matches(regexp [, number_of_frames])
2187 ** $_any_caller_is(name [, number_of_frames])
2188 ** $_any_caller_matches(regexp [, number_of_frames])
2190 * GDB now supports the compilation and injection of source code into
2191 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
2192 to compile the source code to object code, and if successful, inject
2193 and execute that code within the current context of the inferior.
2194 Currently the C language is supported. The commands used to
2195 interface with this new feature are:
2197 compile code [-raw|-r] [--] [source code]
2198 compile file [-raw|-r] filename
2202 demangle [-l language] [--] name
2203 Demangle "name" in the specified language, or the current language
2204 if elided. This command is renamed from the "maint demangle" command.
2205 The latter is kept as a no-op to avoid "maint demangle" being interpreted
2206 as "maint demangler-warning".
2208 queue-signal signal-name-or-number
2209 Queue a signal to be delivered to the thread when it is resumed.
2211 add-auto-load-scripts-directory directory
2212 Add entries to the list of directories from which to load auto-loaded
2215 maint print user-registers
2216 List all currently available "user" registers.
2218 compile code [-r|-raw] [--] [source code]
2219 Compile, inject, and execute in the inferior the executable object
2220 code produced by compiling the provided source code.
2222 compile file [-r|-raw] filename
2223 Compile and inject into the inferior the executable object code
2224 produced by compiling the source code stored in the filename
2227 * On resume, GDB now always passes the signal the program had stopped
2228 for to the thread the signal was sent to, even if the user changed
2229 threads before resuming. Previously GDB would often (but not
2230 always) deliver the signal to the thread that happens to be current
2233 * Conversely, the "signal" command now consistently delivers the
2234 requested signal to the current thread. GDB now asks for
2235 confirmation if the program had stopped for a signal and the user
2236 switched threads meanwhile.
2238 * "breakpoint always-inserted" modes "off" and "auto" merged.
2240 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
2241 won't remove breakpoints from the target until all threads stop,
2242 even in non-stop mode. The "auto" mode has been removed, and "off"
2243 is now the default mode.
2247 set debug symbol-lookup
2248 show debug symbol-lookup
2249 Control display of debugging info regarding symbol lookup.
2253 ** The -list-thread-groups command outputs an exit-code field for
2254 inferiors that have exited.
2258 MIPS SDE mips*-sde*-elf*
2262 Support for these obsolete configurations has been removed.
2264 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
2265 SGI Irix-5.x mips-*-irix5*
2266 SGI Irix-6.x mips-*-irix6*
2267 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
2268 VAX running Ultrix vax-*-ultrix*
2270 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2271 and "assf"), have been removed. Use the "sharedlibrary" command, or
2272 its alias "share", instead.
2274 *** Changes in GDB 7.8
2276 * New command line options
2279 This is an alias for the --data-directory option.
2281 * GDB supports printing and modifying of variable length automatic arrays
2282 as specified in ISO C99.
2284 * The ARM simulator now supports instruction level tracing
2285 with or without disassembly.
2289 GDB now has support for scripting using Guile. Whether this is
2290 available is determined at configure time.
2291 Guile version 2.0 or greater is required.
2292 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
2294 * New commands (for set/show, see "New options" below)
2298 Invoke CODE by passing it to the Guile interpreter.
2302 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
2304 info auto-load guile-scripts [regexp]
2305 Print the list of automatically loaded Guile scripts.
2307 * The source command is now capable of sourcing Guile scripts.
2308 This feature is dependent on the debugger being built with Guile support.
2312 set print symbol-loading (off|brief|full)
2313 show print symbol-loading
2314 Control whether to print informational messages when loading symbol
2315 information for a file. The default is "full", but when debugging
2316 programs with large numbers of shared libraries the amount of output
2317 becomes less useful.
2319 set guile print-stack (none|message|full)
2320 show guile print-stack
2321 Show a stack trace when an error is encountered in a Guile script.
2323 set auto-load guile-scripts (on|off)
2324 show auto-load guile-scripts
2325 Control auto-loading of Guile script files.
2327 maint ada set ignore-descriptive-types (on|off)
2328 maint ada show ignore-descriptive-types
2329 Control whether the debugger should ignore descriptive types in Ada
2330 programs. The default is not to ignore the descriptive types. See
2331 the user manual for more details on descriptive types and the intended
2332 usage of this option.
2334 set auto-connect-native-target
2336 Control whether GDB is allowed to automatically connect to the
2337 native target for the run, attach, etc. commands when not connected
2338 to any target yet. See also "target native" below.
2340 set record btrace replay-memory-access (read-only|read-write)
2341 show record btrace replay-memory-access
2342 Control what memory accesses are allowed during replay.
2344 maint set target-async (on|off)
2345 maint show target-async
2346 This controls whether GDB targets operate in synchronous or
2347 asynchronous mode. Normally the default is asynchronous, if it is
2348 available; but this can be changed to more easily debug problems
2349 occurring only in synchronous mode.
2351 set mi-async (on|off)
2353 Control whether MI asynchronous mode is preferred. This supersedes
2354 "set target-async" of previous GDB versions.
2356 * "set target-async" is deprecated as a CLI option and is now an alias
2357 for "set mi-async" (only puts MI into async mode).
2359 * Background execution commands (e.g., "c&", "s&", etc.) are now
2360 possible ``out of the box'' if the target supports them. Previously
2361 the user would need to explicitly enable the possibility with the
2362 "set target-async on" command.
2364 * New features in the GDB remote stub, GDBserver
2366 ** New option --debug-format=option1[,option2,...] allows one to add
2367 additional text to each output. At present only timestamps
2368 are supported: --debug-format=timestamps.
2369 Timestamps can also be turned on with the
2370 "monitor set debug-format timestamps" command from GDB.
2372 * The 'record instruction-history' command now starts counting instructions
2373 at one. This also affects the instruction ranges reported by the
2374 'record function-call-history' command when given the /i modifier.
2376 * The command 'record function-call-history' supports a new modifier '/c' to
2377 indent the function names based on their call stack depth.
2378 The fields for the '/i' and '/l' modifier have been reordered.
2379 The source line range is now prefixed with 'at'.
2380 The instruction range is now prefixed with 'inst'.
2381 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
2382 "record instruction-history" and "list" commands.
2384 * The ranges given as arguments to the 'record function-call-history' and
2385 'record instruction-history' commands are now inclusive.
2387 * The btrace record target now supports the 'record goto' command.
2388 For locations inside the execution trace, the back trace is computed
2389 based on the information stored in the execution trace.
2391 * The btrace record target supports limited reverse execution and replay.
2392 The target does not record data and therefore does not allow reading
2393 memory or registers.
2395 * The "catch syscall" command now works on s390*-linux* targets.
2397 * The "compare-sections" command is no longer specific to target
2398 remote. It now works with all targets.
2400 * All native targets are now consistently called "native".
2401 Consequently, the "target child", "target GNU", "target djgpp",
2402 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
2403 commands have been replaced with "target native". The QNX/NTO port
2404 leaves the "procfs" target in place and adds a "native" target for
2405 consistency with other ports. The impact on users should be minimal
2406 as these commands previously either throwed an error, or were
2407 no-ops. The target's name is visible in the output of the following
2408 commands: "help target", "info target", "info files", "maint print
2411 * The "target native" command now connects to the native target. This
2412 can be used to launch native programs even when "set
2413 auto-connect-native-target" is set to off.
2415 * GDB now supports access to Intel MPX registers on GNU/Linux.
2417 * Support for Intel AVX-512 registers on GNU/Linux.
2418 Support displaying and modifying Intel AVX-512 registers
2419 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
2421 * New remote packets
2423 qXfer:btrace:read's annex
2424 The qXfer:btrace:read packet supports a new annex 'delta' to read
2425 branch trace incrementally.
2429 ** Valid Python operations on gdb.Value objects representing
2430 structs/classes invoke the corresponding overloaded operators if
2432 ** New `Xmethods' feature in the Python API. Xmethods are
2433 additional methods or replacements for existing methods of a C++
2434 class. This feature is useful for those cases where a method
2435 defined in C++ source code could be inlined or optimized out by
2436 the compiler, making it unavailable to GDB.
2439 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
2441 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2442 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
2443 its alias "share", instead.
2445 * The commands "set remotebaud" and "show remotebaud" are no longer
2446 supported. Use "set serial baud" and "show serial baud" (respectively)
2451 ** A new option "-gdb-set mi-async" replaces "-gdb-set
2452 target-async". The latter is left as a deprecated alias of the
2453 former for backward compatibility. If the target supports it,
2454 CLI background execution commands are now always possible by
2455 default, independently of whether the frontend stated a
2456 preference for asynchronous execution with "-gdb-set mi-async".
2457 Previously "-gdb-set target-async off" affected both MI execution
2458 commands and CLI execution commands.
2460 *** Changes in GDB 7.7
2462 * Improved support for process record-replay and reverse debugging on
2463 arm*-linux* targets. Support for thumb32 and syscall instruction
2464 recording has been added.
2466 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
2468 * GDB now supports Fission DWP file format version 2.
2469 http://gcc.gnu.org/wiki/DebugFission
2471 * New convenience function "$_isvoid", to check whether an expression
2472 is void. A void expression is an expression where the type of the
2473 result is "void". For example, some convenience variables may be
2474 "void" when evaluated (e.g., "$_exitcode" before the execution of
2475 the program being debugged; or an undefined convenience variable).
2476 Another example, when calling a function whose return type is
2479 * The "maintenance print objfiles" command now takes an optional regexp.
2481 * The "catch syscall" command now works on arm*-linux* targets.
2483 * GDB now consistently shows "<not saved>" when printing values of
2484 registers the debug info indicates have not been saved in the frame
2485 and there's nowhere to retrieve them from
2486 (callee-saved/call-clobbered registers):
2491 (gdb) info registers rax
2494 Before, the former would print "<optimized out>", and the latter
2495 "*value not available*".
2497 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
2502 ** Frame filters and frame decorators have been added.
2503 ** Temporary breakpoints are now supported.
2504 ** Line tables representation has been added.
2505 ** New attribute 'parent_type' for gdb.Field objects.
2506 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
2507 ** New attribute 'name' for gdb.Type objects.
2511 Nios II ELF nios2*-*-elf
2512 Nios II GNU/Linux nios2*-*-linux
2513 Texas Instruments MSP430 msp430*-*-elf
2515 * Removed native configurations
2517 Support for these a.out NetBSD and OpenBSD obsolete configurations has
2518 been removed. ELF variants of these configurations are kept supported.
2520 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
2521 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
2522 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
2523 i[34567]86-*-openbsd3.[0-3]
2524 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
2525 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
2526 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
2530 Like "catch throw", but catches a re-thrown exception.
2531 maint check-psymtabs
2532 Renamed from old "maint check-symtabs".
2534 Perform consistency checks on symtabs.
2535 maint expand-symtabs
2536 Expand symtabs matching an optional regexp.
2539 Display the details of GDB configure-time options.
2541 maint set|show per-command
2542 maint set|show per-command space
2543 maint set|show per-command time
2544 maint set|show per-command symtab
2545 Enable display of per-command gdb resource usage.
2547 remove-symbol-file FILENAME
2548 remove-symbol-file -a ADDRESS
2549 Remove a symbol file added via add-symbol-file. The file to remove
2550 can be identified by its filename or by an address that lies within
2551 the boundaries of this symbol file in memory.
2554 info exceptions REGEXP
2555 Display the list of Ada exceptions defined in the program being
2556 debugged. If provided, only the exceptions whose names match REGEXP
2561 set debug symfile off|on
2563 Control display of debugging info regarding reading symbol files and
2564 symbol tables within those files
2566 set print raw frame-arguments
2567 show print raw frame-arguments
2568 Set/show whether to print frame arguments in raw mode,
2569 disregarding any defined pretty-printers.
2571 set remote trace-status-packet
2572 show remote trace-status-packet
2573 Set/show the use of remote protocol qTStatus packet.
2577 Control display of debugging messages related to Nios II targets.
2581 Control whether target-assisted range stepping is enabled.
2583 set startup-with-shell
2584 show startup-with-shell
2585 Specifies whether Unix child processes are started via a shell or
2590 Use the target memory cache for accesses to the code segment. This
2591 improves performance of remote debugging (particularly disassembly).
2593 * You can now use a literal value 'unlimited' for options that
2594 interpret 0 or -1 as meaning "unlimited". E.g., "set
2595 trace-buffer-size unlimited" is now an alias for "set
2596 trace-buffer-size -1" and "set height unlimited" is now an alias for
2599 * The "set debug symtab-create" debugging option of GDB has been changed to
2600 accept a verbosity level. 0 means "off", 1 provides basic debugging
2601 output, and values of 2 or greater provides more verbose output.
2603 * New command-line options
2605 Display the details of GDB configure-time options.
2607 * The command 'tsave' can now support new option '-ctf' to save trace
2608 buffer in Common Trace Format.
2610 * Newly installed $prefix/bin/gcore acts as a shell interface for the
2613 * GDB now implements the C++ 'typeid' operator.
2615 * The new convenience variable $_exception holds the exception being
2616 thrown or caught at an exception-related catchpoint.
2618 * The exception-related catchpoints, like "catch throw", now accept a
2619 regular expression which can be used to filter exceptions by type.
2621 * The new convenience variable $_exitsignal is automatically set to
2622 the terminating signal number when the program being debugged dies
2623 due to an uncaught signal.
2627 ** All MI commands now accept an optional "--language" option.
2628 Support for this feature can be verified by using the "-list-features"
2629 command, which should contain "language-option".
2631 ** The new command -info-gdb-mi-command allows the user to determine
2632 whether a GDB/MI command is supported or not.
2634 ** The "^error" result record returned when trying to execute an undefined
2635 GDB/MI command now provides a variable named "code" whose content is the
2636 "undefined-command" error code. Support for this feature can be verified
2637 by using the "-list-features" command, which should contain
2638 "undefined-command-error-code".
2640 ** The -trace-save MI command can optionally save trace buffer in Common
2643 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2645 ** The command -data-list-register-values now accepts an optional
2646 "--skip-unavailable" option. When used, only the available registers
2649 ** The new command -trace-frame-collected dumps collected variables,
2650 computed expressions, tvars, memory and registers in a traceframe.
2652 ** The commands -stack-list-locals, -stack-list-arguments and
2653 -stack-list-variables now accept an option "--skip-unavailable".
2654 When used, only the available locals or arguments are displayed.
2656 ** The -exec-run command now accepts an optional "--start" option.
2657 When used, the command follows the same semantics as the "start"
2658 command, stopping the program's execution at the start of its
2659 main subprogram. Support for this feature can be verified using
2660 the "-list-features" command, which should contain
2661 "exec-run-start-option".
2663 ** The new commands -catch-assert and -catch-exceptions insert
2664 catchpoints stopping the program when Ada exceptions are raised.
2666 ** The new command -info-ada-exceptions provides the equivalent of
2667 the new "info exceptions" command.
2669 * New system-wide configuration scripts
2670 A GDB installation now provides scripts suitable for use as system-wide
2671 configuration scripts for the following systems:
2675 * GDB now supports target-assigned range stepping with remote targets.
2676 This improves the performance of stepping source lines by reducing
2677 the number of control packets from/to GDB. See "New remote packets"
2680 * GDB now understands the element 'tvar' in the XML traceframe info.
2681 It has the id of the collected trace state variables.
2683 * On S/390 targets that provide the transactional-execution feature,
2684 the program interruption transaction diagnostic block (TDB) is now
2685 represented as a number of additional "registers" in GDB.
2687 * New remote packets
2691 The vCont packet supports a new 'r' action, that tells the remote
2692 stub to step through an address range itself, without GDB
2693 involvemement at each single-step.
2695 qXfer:libraries-svr4:read's annex
2696 The previously unused annex of the qXfer:libraries-svr4:read packet
2697 is now used to support passing an argument list. The remote stub
2698 reports support for this argument list to GDB's qSupported query.
2699 The defined arguments are "start" and "prev", used to reduce work
2700 necessary for library list updating, resulting in significant
2703 * New features in the GDB remote stub, GDBserver
2705 ** GDBserver now supports target-assisted range stepping. Currently
2706 enabled on x86/x86_64 GNU/Linux targets.
2708 ** GDBserver now adds element 'tvar' in the XML in the reply to
2709 'qXfer:traceframe-info:read'. It has the id of the collected
2710 trace state variables.
2712 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2715 * New 'z' formatter for printing and examining memory, this displays the
2716 value as hexadecimal zero padded on the left to the size of the type.
2718 * GDB can now use Windows x64 unwinding data.
2720 * The "set remotebaud" command has been replaced by "set serial baud".
2721 Similarly, "show remotebaud" has been replaced by "show serial baud".
2722 The "set remotebaud" and "show remotebaud" commands are still available
2723 to provide backward compatibility with older versions of GDB.
2725 *** Changes in GDB 7.6
2727 * Target record has been renamed to record-full.
2728 Record/replay is now enabled with the "record full" command.
2729 This also affects settings that are associated with full record/replay
2730 that have been moved from "set/show record" to "set/show record full":
2732 set|show record full insn-number-max
2733 set|show record full stop-at-limit
2734 set|show record full memory-query
2736 * A new record target "record-btrace" has been added. The new target
2737 uses hardware support to record the control-flow of a process. It
2738 does not support replaying the execution, but it implements the
2739 below new commands for investigating the recorded execution log.
2740 This new recording method can be enabled using:
2744 The "record-btrace" target is only available on Intel Atom processors
2745 and requires a Linux kernel 2.6.32 or later.
2747 * Two new commands have been added for record/replay to give information
2748 about the recorded execution without having to replay the execution.
2749 The commands are only supported by "record btrace".
2751 record instruction-history prints the execution history at
2752 instruction granularity
2754 record function-call-history prints the execution history at
2755 function granularity
2757 * New native configurations
2759 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2760 FreeBSD/powerpc powerpc*-*-freebsd
2761 x86_64/Cygwin x86_64-*-cygwin*
2762 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2766 ARM AArch64 aarch64*-*-elf
2767 ARM AArch64 GNU/Linux aarch64*-*-linux
2768 Lynx 178 PowerPC powerpc-*-lynx*178
2769 x86_64/Cygwin x86_64-*-cygwin*
2770 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2772 * If the configured location of system.gdbinit file (as given by the
2773 --with-system-gdbinit option at configure time) is in the
2774 data-directory (as specified by --with-gdb-datadir at configure
2775 time) or in one of its subdirectories, then GDB will look for the
2776 system-wide init file in the directory specified by the
2777 --data-directory command-line option.
2779 * New command line options:
2781 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2782 other initialization files, unlike -nx which disables all of them.
2784 * Removed command line options
2786 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2789 * The 'ptype' and 'whatis' commands now accept an argument to control
2792 * 'info proc' now works on some core files.
2796 ** Vectors can be created with gdb.Type.vector.
2798 ** Python's atexit.register now works in GDB.
2800 ** Types can be pretty-printed via a Python API.
2802 ** Python 3 is now supported (in addition to Python 2.4 or later)
2804 ** New class gdb.Architecture exposes GDB's internal representation
2805 of architecture in the Python API.
2807 ** New method Frame.architecture returns the gdb.Architecture object
2808 corresponding to the frame's architecture.
2810 * New Python-based convenience functions:
2812 ** $_memeq(buf1, buf2, length)
2813 ** $_streq(str1, str2)
2815 ** $_regex(str, regex)
2817 * The 'cd' command now defaults to using '~' (the home directory) if not
2820 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2821 default for GCC since November 2000.
2823 * The command 'forward-search' can now be abbreviated as 'fo'.
2825 * The command 'info tracepoints' can now display 'installed on target'
2826 or 'not installed on target' for each non-pending location of tracepoint.
2828 * New configure options
2830 --enable-libmcheck/--disable-libmcheck
2831 By default, development versions are built with -lmcheck on hosts
2832 that support it, in order to help track memory corruption issues.
2833 Release versions, on the other hand, are built without -lmcheck
2834 by default. The --enable-libmcheck/--disable-libmcheck configure
2835 options allow the user to override that default.
2836 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2837 This configure option allows the user to build GDB with
2838 libbabeltrace using which GDB can read Common Trace Format data.
2840 * New commands (for set/show, see "New options" below)
2843 Catch signals. This is similar to "handle", but allows commands and
2844 conditions to be attached.
2847 List the BFDs known to GDB.
2849 python-interactive [command]
2851 Start a Python interactive prompt, or evaluate the optional command
2852 and print the result of expressions.
2855 "py" is a new alias for "python".
2857 enable type-printer [name]...
2858 disable type-printer [name]...
2859 Enable or disable type printers.
2863 ** For the Renesas Super-H architecture, the "regs" command has been removed
2864 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2869 set print type methods (on|off)
2870 show print type methods
2871 Control whether method declarations are displayed by "ptype".
2872 The default is to show them.
2874 set print type typedefs (on|off)
2875 show print type typedefs
2876 Control whether typedef definitions are displayed by "ptype".
2877 The default is to show them.
2879 set filename-display basename|relative|absolute
2880 show filename-display
2881 Control the way in which filenames is displayed.
2882 The default is "relative", which preserves previous behavior.
2884 set trace-buffer-size
2885 show trace-buffer-size
2886 Request target to change the size of trace buffer.
2888 set remote trace-buffer-size-packet auto|on|off
2889 show remote trace-buffer-size-packet
2890 Control the use of the remote protocol `QTBuffer:size' packet.
2894 Control display of debugging messages related to ARM AArch64.
2897 set debug coff-pe-read
2898 show debug coff-pe-read
2899 Control display of debugging messages related to reading of COFF/PE
2904 Control display of debugging messages related to Mach-O symbols
2907 set debug notification
2908 show debug notification
2909 Control display of debugging info for async remote notification.
2913 ** Command parameter changes are now notified using new async record
2914 "=cmd-param-changed".
2915 ** Trace frame changes caused by command "tfind" are now notified using
2916 new async record "=traceframe-changed".
2917 ** The creation, deletion and modification of trace state variables
2918 are now notified using new async records "=tsv-created",
2919 "=tsv-deleted" and "=tsv-modified".
2920 ** The start and stop of process record are now notified using new
2921 async record "=record-started" and "=record-stopped".
2922 ** Memory changes are now notified using new async record
2924 ** The data-disassemble command response will include a "fullname" field
2925 containing the absolute file name when source has been requested.
2926 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
2927 command, to allow pattern filling of memory areas.
2928 ** New commands "-catch-load"/"-catch-unload" added for intercepting
2929 library load/unload events.
2930 ** The response to breakpoint commands and breakpoint async records
2931 includes an "installed" field containing a boolean state about each
2932 non-pending tracepoint location is whether installed on target or not.
2933 ** Output of the "-trace-status" command includes a "trace-file" field
2934 containing the name of the trace file being examined. This field is
2935 optional, and only present when examining a trace file.
2936 ** The "fullname" field is now always present along with the "file" field,
2937 even if the file cannot be found by GDB.
2939 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
2940 You must have the LZMA library available when configuring GDB for this
2941 feature to be enabled. For more information, see:
2942 http://fedoraproject.org/wiki/Features/MiniDebugInfo
2944 * New remote packets
2947 Set the size of trace buffer. The remote stub reports support for this
2948 packet to gdb's qSupported query.
2951 Enable Branch Trace Store (BTS)-based branch tracing for the current
2952 thread. The remote stub reports support for this packet to gdb's
2956 Disable branch tracing for the current thread. The remote stub reports
2957 support for this packet to gdb's qSupported query.
2960 Read the traced branches for the current thread. The remote stub
2961 reports support for this packet to gdb's qSupported query.
2963 *** Changes in GDB 7.5
2965 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2966 for more x32 ABI info.
2968 * GDB now supports access to MIPS DSP registers on Linux targets.
2970 * GDB now supports debugging microMIPS binaries.
2972 * The "info os" command on GNU/Linux can now display information on
2973 several new classes of objects managed by the operating system:
2974 "info os procgroups" lists process groups
2975 "info os files" lists file descriptors
2976 "info os sockets" lists internet-domain sockets
2977 "info os shm" lists shared-memory regions
2978 "info os semaphores" lists semaphores
2979 "info os msg" lists message queues
2980 "info os modules" lists loaded kernel modules
2982 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2983 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2984 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2985 options and inspect the probe arguments using the new $_probe_arg family
2986 of convenience variables. You can obtain more information about SystemTap
2987 in <http://sourceware.org/systemtap/>.
2989 * GDB now supports reversible debugging on ARM, it allows you to
2990 debug basic ARM and THUMB instructions, and provides
2991 record/replay support.
2993 * The option "symbol-reloading" has been deleted as it is no longer used.
2997 ** GDB commands implemented in Python can now be put in command class
3000 ** The "maint set python print-stack on|off" is now deleted.
3002 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
3003 apply "flag enum"-style pretty-printing to any enum.
3005 ** gdb.lookup_symbol can now work when there is no current frame.
3007 ** gdb.Symbol now has a 'line' attribute, holding the line number in
3008 the source at which the symbol was defined.
3010 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
3011 method 'value'. The former indicates whether the symbol needs a
3012 frame in order to compute its value, and the latter computes the
3015 ** A new method 'referenced_value' on gdb.Value objects which can
3016 dereference pointer as well as C++ reference values.
3018 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
3019 which return the global and static blocks (as gdb.Block objects),
3020 of the underlying symbol table, respectively.
3022 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
3023 object associated with a PC value.
3025 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
3026 of the address range occupied by code for the current source line.
3028 * Go language support.
3029 GDB now supports debugging programs written in the Go programming
3032 * GDBserver now supports stdio connections.
3033 E.g. (gdb) target remote | ssh myhost gdbserver - hello
3035 * The binary "gdbtui" can no longer be built or installed.
3036 Use "gdb -tui" instead.
3038 * GDB will now print "flag" enums specially. A flag enum is one where
3039 all the enumerator values have no bits in common when pairwise
3040 "and"ed. When printing a value whose type is a flag enum, GDB will
3041 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
3042 (gdb) print (enum E) 3
3045 * The filename part of a linespec will now match trailing components
3046 of a source file name. For example, "break gcc/expr.c:1000" will
3047 now set a breakpoint in build/gcc/expr.c, but not
3048 build/libcpp/expr.c.
3050 * The "info proc" and "generate-core-file" commands will now also
3051 work on remote targets connected to GDBserver on Linux.
3053 * The command "info catch" has been removed. It has been disabled
3054 since December 2007.
3056 * The "catch exception" and "catch assert" commands now accept
3057 a condition at the end of the command, much like the "break"
3058 command does. For instance:
3060 (gdb) catch exception Constraint_Error if Barrier = True
3062 Previously, it was possible to add a condition to such catchpoints,
3063 but it had to be done as a second step, after the catchpoint had been
3064 created, using the "condition" command.
3066 * The "info static-tracepoint-marker" command will now also work on
3067 native Linux targets with in-process agent.
3069 * GDB can now set breakpoints on inlined functions.
3071 * The .gdb_index section has been updated to include symbols for
3072 inlined functions. GDB will ignore older .gdb_index sections by
3073 default, which could cause symbol files to be loaded more slowly
3074 until their .gdb_index sections can be recreated. The new command
3075 "set use-deprecated-index-sections on" will cause GDB to use any older
3076 .gdb_index sections it finds. This will restore performance, but the
3077 ability to set breakpoints on inlined functions will be lost in symbol
3078 files with older .gdb_index sections.
3080 The .gdb_index section has also been updated to record more information
3081 about each symbol. This speeds up the "info variables", "info functions"
3082 and "info types" commands when used with programs having the .gdb_index
3083 section, as well as speeding up debugging with shared libraries using
3084 the .gdb_index section.
3086 * Ada support for GDB/MI Variable Objects has been added.
3088 * GDB can now support 'breakpoint always-inserted mode' in 'record'
3093 ** New command -info-os is the MI equivalent of "info os".
3095 ** Output logs ("set logging" and related) now include MI output.
3099 ** "set use-deprecated-index-sections on|off"
3100 "show use-deprecated-index-sections on|off"
3101 Controls the use of deprecated .gdb_index sections.
3103 ** "catch load" and "catch unload" can be used to stop when a shared
3104 library is loaded or unloaded, respectively.
3106 ** "enable count" can be used to auto-disable a breakpoint after
3109 ** "info vtbl" can be used to show the virtual method tables for
3110 C++ and Java objects.
3112 ** "explore" and its sub commands "explore value" and "explore type"
3113 can be used to recursively explore values and types of
3114 expressions. These commands are available only if GDB is
3115 configured with '--with-python'.
3117 ** "info auto-load" shows status of all kinds of auto-loaded files,
3118 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
3119 sequences of commands files, "info auto-load python-scripts"
3120 shows status of auto-loading Python script files,
3121 "info auto-load local-gdbinit" shows status of loading init file
3122 (.gdbinit) from current directory and "info auto-load libthread-db" shows
3123 status of inferior specific thread debugging shared library loading.
3125 ** "info auto-load-scripts", "set auto-load-scripts on|off"
3126 and "show auto-load-scripts" commands have been deprecated, use their
3127 "info auto-load python-scripts", "set auto-load python-scripts on|off"
3128 and "show auto-load python-scripts" counterparts instead.
3130 ** "dprintf location,format,args..." creates a dynamic printf, which
3131 is basically a breakpoint that does a printf and immediately
3132 resumes your program's execution, so it is like a printf that you
3133 can insert dynamically at runtime instead of at compiletime.
3135 ** "set print symbol"
3137 Controls whether GDB attempts to display the symbol, if any,
3138 corresponding to addresses it prints. This defaults to "on", but
3139 you can set it to "off" to restore GDB's previous behavior.
3141 * Deprecated commands
3143 ** For the Renesas Super-H architecture, the "regs" command has been
3144 deprecated, and "info all-registers" should be used instead.
3148 Renesas RL78 rl78-*-elf
3149 HP OpenVMS ia64 ia64-hp-openvms*
3151 * GDBserver supports evaluation of breakpoint conditions. When
3152 support is advertised by GDBserver, GDB may be told to send the
3153 breakpoint conditions in bytecode form to GDBserver. GDBserver
3154 will only report the breakpoint trigger to GDB when its condition
3159 set mips compression
3160 show mips compression
3161 Select the compressed ISA encoding used in functions that have no symbol
3162 information available. The encoding can be set to either of:
3165 and is updated automatically from ELF file flags if available.
3167 set breakpoint condition-evaluation
3168 show breakpoint condition-evaluation
3169 Control whether breakpoint conditions are evaluated by GDB ("host") or by
3170 GDBserver ("target"). Default option "auto" chooses the most efficient
3172 This option can improve debugger efficiency depending on the speed of the
3176 Disable auto-loading globally.
3179 Show auto-loading setting of all kinds of auto-loaded files.
3181 set auto-load gdb-scripts on|off
3182 show auto-load gdb-scripts
3183 Control auto-loading of GDB canned sequences of commands files.
3185 set auto-load python-scripts on|off
3186 show auto-load python-scripts
3187 Control auto-loading of Python script files.
3189 set auto-load local-gdbinit on|off
3190 show auto-load local-gdbinit
3191 Control loading of init file (.gdbinit) from current directory.
3193 set auto-load libthread-db on|off
3194 show auto-load libthread-db
3195 Control auto-loading of inferior specific thread debugging shared library.
3197 set auto-load scripts-directory <dir1>[:<dir2>...]
3198 show auto-load scripts-directory
3199 Set a list of directories from which to load auto-loaded scripts.
3200 Automatically loaded Python scripts and GDB scripts are located in one
3201 of the directories listed by this option.
3202 The delimiter (':' above) may differ according to the host platform.
3204 set auto-load safe-path <dir1>[:<dir2>...]
3205 show auto-load safe-path
3206 Set a list of directories from which it is safe to auto-load files.
3207 The delimiter (':' above) may differ according to the host platform.
3209 set debug auto-load on|off
3210 show debug auto-load
3211 Control display of debugging info for auto-loading the files above.
3213 set dprintf-style gdb|call|agent
3215 Control the way in which a dynamic printf is performed; "gdb"
3216 requests a GDB printf command, while "call" causes dprintf to call a
3217 function in the inferior. "agent" requests that the target agent
3218 (such as GDBserver) do the printing.
3220 set dprintf-function <expr>
3221 show dprintf-function
3222 set dprintf-channel <expr>
3223 show dprintf-channel
3224 Set the function and optional first argument to the call when using
3225 the "call" style of dynamic printf.
3227 set disconnected-dprintf on|off
3228 show disconnected-dprintf
3229 Control whether agent-style dynamic printfs continue to be in effect
3230 after GDB disconnects.
3232 * New configure options
3234 --with-auto-load-dir
3235 Configure default value for the 'set auto-load scripts-directory'
3236 setting above. It defaults to '$debugdir:$datadir/auto-load',
3237 $debugdir representing global debugging info directories (available
3238 via 'show debug-file-directory') and $datadir representing GDB's data
3239 directory (available via 'show data-directory').
3241 --with-auto-load-safe-path
3242 Configure default value for the 'set auto-load safe-path' setting
3243 above. It defaults to the --with-auto-load-dir setting.
3245 --without-auto-load-safe-path
3246 Set 'set auto-load safe-path' to '/', effectively disabling this
3249 * New remote packets
3251 z0/z1 conditional breakpoints extension
3253 The z0/z1 breakpoint insertion packets have been extended to carry
3254 a list of conditional expressions over to the remote stub depending on the
3255 condition evaluation mode. The use of this extension can be controlled
3256 via the "set remote conditional-breakpoints-packet" command.
3260 Specify the signals which the remote stub may pass to the debugged
3261 program without GDB involvement.
3263 * New command line options
3265 --init-command=FILE, -ix Like --command, -x but execute it
3266 before loading inferior.
3267 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
3268 execute it before loading inferior.
3270 *** Changes in GDB 7.4
3272 * GDB now handles ambiguous linespecs more consistently; the existing
3273 FILE:LINE support has been expanded to other types of linespecs. A
3274 breakpoint will now be set on all matching locations in all
3275 inferiors, and locations will be added or removed according to
3278 * GDB now allows you to skip uninteresting functions and files when
3279 stepping with the "skip function" and "skip file" commands.
3281 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
3282 and "show remote hardware-watchpoint-length-limit". These allows to
3283 set or show the maximum length limit (in bytes) of a remote
3284 target hardware watchpoint.
3286 This allows e.g. to use "unlimited" hardware watchpoints with the
3287 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
3288 watchpoints are slower than real hardware watchpoints but are
3289 significantly faster than gdb software watchpoints.
3293 ** The register_pretty_printer function in module gdb.printing now takes
3294 an optional `replace' argument. If True, the new printer replaces any
3297 ** The "maint set python print-stack on|off" command has been
3298 deprecated and will be deleted in GDB 7.5.
3299 A new command: "set python print-stack none|full|message" has
3300 replaced it. Additionally, the default for "print-stack" is
3301 now "message", which just prints the error message without
3304 ** A prompt substitution hook (prompt_hook) is now available to the
3307 ** A new Python module, gdb.prompt has been added to the GDB Python
3308 modules library. This module provides functionality for
3309 escape sequences in prompts (used by set/show
3310 extended-prompt). These escape sequences are replaced by their
3311 corresponding value.
3313 ** Python commands and convenience-functions located in
3314 'data-directory'/python/gdb/command and
3315 'data-directory'/python/gdb/function are now automatically loaded
3318 ** Blocks now provide four new attributes. global_block and
3319 static_block will return the global and static blocks
3320 respectively. is_static and is_global are boolean attributes
3321 that indicate if the block is one of those two types.
3323 ** Symbols now provide the "type" attribute, the type of the symbol.
3325 ** The "gdb.breakpoint" function has been deprecated in favor of
3328 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
3329 of a function. This class is based on the "finish" command
3330 available in the CLI.
3332 ** Type objects for struct and union types now allow access to
3333 the fields using standard Python dictionary (mapping) methods.
3334 For example, "some_type['myfield']" now works, as does
3335 "some_type.items()".
3337 ** A new event "gdb.new_objfile" has been added, triggered by loading a
3340 ** A new function, "deep_items" has been added to the gdb.types
3341 module in the GDB Python modules library. This function returns
3342 an iterator over the fields of a struct or union type. Unlike
3343 the standard Python "iteritems" method, it will recursively traverse
3344 any anonymous fields.
3348 ** "*stopped" events can report several new "reason"s, such as
3351 ** Breakpoint changes are now notified using new async records, like
3352 "=breakpoint-modified".
3354 ** New command -ada-task-info.
3356 * libthread-db-search-path now supports two special values: $sdir and $pdir.
3357 $sdir specifies the default system locations of shared libraries.
3358 $pdir specifies the directory where the libpthread used by the application
3361 GDB no longer looks in $sdir and $pdir after it has searched the directories
3362 mentioned in libthread-db-search-path. If you want to search those
3363 directories, they must be specified in libthread-db-search-path.
3364 The default value of libthread-db-search-path on GNU/Linux and Solaris
3365 systems is now "$sdir:$pdir".
3367 $pdir is not supported by gdbserver, it is currently ignored.
3368 $sdir is supported by gdbserver.
3370 * New configure option --with-iconv-bin.
3371 When using the internationalization support like the one in the GNU C
3372 library, GDB will invoke the "iconv" program to get a list of supported
3373 character sets. If this program lives in a non-standard location, one can
3374 use this option to specify where to find it.
3376 * When natively debugging programs on PowerPC BookE processors running
3377 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
3378 watchpoints, which specify a mask in addition to an address to watch.
3379 The mask specifies that some bits of an address (the bits which are
3380 reset in the mask) should be ignored when matching the address accessed
3381 by the inferior against the watchpoint address. See the "PowerPC Embedded"
3382 section in the user manual for more details.
3384 * The new option --once causes GDBserver to stop listening for connections once
3385 the first connection is made. The listening port used by GDBserver will
3386 become available after that.
3388 * New commands "info macros" and "alias" have been added.
3390 * New function parameters suffix @entry specifies value of function parameter
3391 at the time the function got called. Entry values are available only since
3397 "!" is now an alias of the "shell" command.
3398 Note that no space is needed between "!" and SHELL COMMAND.
3402 watch EXPRESSION mask MASK_VALUE
3403 The watch command now supports the mask argument which allows creation
3404 of masked watchpoints, if the current architecture supports this feature.
3406 info auto-load-scripts [REGEXP]
3407 This command was formerly named "maintenance print section-scripts".
3408 It is now generally useful and is no longer a maintenance-only command.
3410 info macro [-all] [--] MACRO
3411 The info macro command has new options `-all' and `--'. The first for
3412 printing all definitions of a macro. The second for explicitly specifying
3413 the end of arguments and the beginning of the macro name in case the macro
3414 name starts with a hyphen.
3416 collect[/s] EXPRESSIONS
3417 The tracepoint collect command now takes an optional modifier "/s"
3418 that directs it to dereference pointer-to-character types and
3419 collect the bytes of memory up to a zero byte. The behavior is
3420 similar to what you see when you use the regular print command on a
3421 string. An optional integer following the "/s" sets a bound on the
3422 number of bytes that will be collected.
3425 The trace start command now interprets any supplied arguments as a
3426 note to be recorded with the trace run, with an effect similar to
3427 setting the variable trace-notes.
3430 The trace stop command now interprets any arguments as a note to be
3431 mentioned along with the tstatus report that the trace was stopped
3432 with a command. The effect is similar to setting the variable
3435 * Tracepoints can now be enabled and disabled at any time after a trace
3436 experiment has been started using the standard "enable" and "disable"
3437 commands. It is now possible to start a trace experiment with no enabled
3438 tracepoints; GDB will display a warning, but will allow the experiment to
3439 begin, assuming that tracepoints will be enabled as needed while the trace
3442 * Fast tracepoints on 32-bit x86-architectures can now be placed at
3443 locations with 4-byte instructions, when they were previously
3444 limited to locations with instructions of 5 bytes or longer.
3448 set debug dwarf2-read
3449 show debug dwarf2-read
3450 Turns on or off display of debugging messages related to reading
3451 DWARF debug info. The default is off.
3453 set debug symtab-create
3454 show debug symtab-create
3455 Turns on or off display of debugging messages related to symbol table
3456 creation. The default is off.
3459 show extended-prompt
3460 Set the GDB prompt, and allow escape sequences to be inserted to
3461 display miscellaneous information (see 'help set extended-prompt'
3462 for the list of sequences). This prompt (and any information
3463 accessed through the escape sequences) is updated every time the
3464 prompt is displayed.
3466 set print entry-values (both|compact|default|if-needed|no|only|preferred)
3467 show print entry-values
3468 Set printing of frame argument values at function entry. In some cases
3469 GDB can determine the value of function argument which was passed by the
3470 function caller, even if the value was modified inside the called function.
3472 set debug entry-values
3473 show debug entry-values
3474 Control display of debugging info for determining frame argument values at
3475 function entry and virtual tail call frames.
3477 set basenames-may-differ
3478 show basenames-may-differ
3479 Set whether a source file may have multiple base names.
3480 (A "base name" is the name of a file with the directory part removed.
3481 Example: The base name of "/home/user/hello.c" is "hello.c".)
3482 If set, GDB will canonicalize file names (e.g., expand symlinks)
3483 before comparing them. Canonicalization is an expensive operation,
3484 but it allows the same file be known by more than one base name.
3485 If not set (the default), all source files are assumed to have just
3486 one base name, and gdb will do file name comparisons more efficiently.
3492 Set a user name and notes for the current and any future trace runs.
3493 This is useful for long-running and/or disconnected traces, to
3494 inform others (or yourself) as to who is running the trace, supply
3495 contact information, or otherwise explain what is going on.
3497 set trace-stop-notes
3498 show trace-stop-notes
3499 Set a note attached to the trace run, that is displayed when the
3500 trace has been stopped by a tstop command. This is useful for
3501 instance as an explanation, if you are stopping a trace run that was
3502 started by someone else.
3504 * New remote packets
3508 Dynamically enable a tracepoint in a started trace experiment.
3512 Dynamically disable a tracepoint in a started trace experiment.
3516 Set the user and notes of the trace run.
3520 Query the current status of a tracepoint.
3524 Query the minimum length of instruction at which a fast tracepoint may
3527 * Dcache size (number of lines) and line-size are now runtime-configurable
3528 via "set dcache line" and "set dcache line-size" commands.
3532 Texas Instruments TMS320C6x tic6x-*-*
3536 Renesas RL78 rl78-*-elf
3538 *** Changes in GDB 7.3.1
3540 * The build failure for NetBSD and OpenBSD targets have now been fixed.
3542 *** Changes in GDB 7.3
3544 * GDB has a new command: "thread find [REGEXP]".
3545 It finds the thread id whose name, target id, or thread extra info
3546 matches the given regular expression.
3548 * The "catch syscall" command now works on mips*-linux* targets.
3550 * The -data-disassemble MI command now supports modes 2 and 3 for
3551 dumping the instruction opcodes.
3553 * New command line options
3555 -data-directory DIR Specify DIR as the "data-directory".
3556 This is mostly for testing purposes.
3558 * The "maint set python auto-load on|off" command has been renamed to
3559 "set auto-load-scripts on|off".
3561 * GDB has a new command: "set directories".
3562 It is like the "dir" command except that it replaces the
3563 source path list instead of augmenting it.
3565 * GDB now understands thread names.
3567 On GNU/Linux, "info threads" will display the thread name as set by
3568 prctl or pthread_setname_np.
3570 There is also a new command, "thread name", which can be used to
3571 assign a name internally for GDB to display.
3574 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
3575 has been integrated into GDB.
3579 ** The function gdb.Write now accepts an optional keyword 'stream'.
3580 This keyword, when provided, will direct the output to either
3581 stdout, stderr, or GDB's logging output.
3583 ** Parameters can now be be sub-classed in Python, and in particular
3584 you may implement the get_set_doc and get_show_doc functions.
3585 This improves how Parameter set/show documentation is processed
3586 and allows for more dynamic content.
3588 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
3589 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
3590 have an is_valid method.
3592 ** Breakpoints can now be sub-classed in Python, and in particular
3593 you may implement a 'stop' function that is executed each time
3594 the inferior reaches that breakpoint.
3596 ** New function gdb.lookup_global_symbol looks up a global symbol.
3598 ** GDB values in Python are now callable if the value represents a
3599 function. For example, if 'some_value' represents a function that
3600 takes two integer parameters and returns a value, you can call
3601 that function like so:
3603 result = some_value (10,20)
3605 ** Module gdb.types has been added.
3606 It contains a collection of utilities for working with gdb.Types objects:
3607 get_basic_type, has_field, make_enum_dict.
3609 ** Module gdb.printing has been added.
3610 It contains utilities for writing and registering pretty-printers.
3611 New classes: PrettyPrinter, SubPrettyPrinter,
3612 RegexpCollectionPrettyPrinter.
3613 New function: register_pretty_printer.
3615 ** New commands "info pretty-printers", "enable pretty-printer" and
3616 "disable pretty-printer" have been added.
3618 ** gdb.parameter("directories") is now available.
3620 ** New function gdb.newest_frame returns the newest frame in the
3623 ** The gdb.InferiorThread class has a new "name" attribute. This
3624 holds the thread's name.
3626 ** Python Support for Inferior events.
3627 Python scripts can add observers to be notified of events
3628 occurring in the process being debugged.
3629 The following events are currently supported:
3630 - gdb.events.cont Continue event.
3631 - gdb.events.exited Inferior exited event.
3632 - gdb.events.stop Signal received, and Breakpoint hit events.
3636 ** GDB now puts template parameters in scope when debugging in an
3637 instantiation. For example, if you have:
3639 template<int X> int func (void) { return X; }
3641 then if you step into func<5>, "print X" will show "5". This
3642 feature requires proper debuginfo support from the compiler; it
3643 was added to GCC 4.5.
3645 ** The motion commands "next", "finish", "until", and "advance" now
3646 work better when exceptions are thrown. In particular, GDB will
3647 no longer lose control of the inferior; instead, the GDB will
3648 stop the inferior at the point at which the exception is caught.
3649 This functionality requires a change in the exception handling
3650 code that was introduced in GCC 4.5.
3652 * GDB now follows GCC's rules on accessing volatile objects when
3653 reading or writing target state during expression evaluation.
3654 One notable difference to prior behavior is that "print x = 0"
3655 no longer generates a read of x; the value of the assignment is
3656 now always taken directly from the value being assigned.
3658 * GDB now has some support for using labels in the program's source in
3659 linespecs. For instance, you can use "advance label" to continue
3660 execution to a label.
3662 * GDB now has support for reading and writing a new .gdb_index
3663 section. This section holds a fast index of DWARF debugging
3664 information and can be used to greatly speed up GDB startup and
3665 operation. See the documentation for `save gdb-index' for details.
3667 * The "watch" command now accepts an optional "-location" argument.
3668 When used, this causes GDB to watch the memory referred to by the
3669 expression. Such a watchpoint is never deleted due to it going out
3672 * GDB now supports thread debugging of core dumps on GNU/Linux.
3674 GDB now activates thread debugging using the libthread_db library
3675 when debugging GNU/Linux core dumps, similarly to when debugging
3676 live processes. As a result, when debugging a core dump file, GDB
3677 is now able to display pthread_t ids of threads. For example, "info
3678 threads" shows the same output as when debugging the process when it
3679 was live. In earlier releases, you'd see something like this:
3682 * 1 LWP 6780 main () at main.c:10
3684 While now you see this:
3687 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3689 It is also now possible to inspect TLS variables when debugging core
3692 When debugging a core dump generated on a machine other than the one
3693 used to run GDB, you may need to point GDB at the correct
3694 libthread_db library with the "set libthread-db-search-path"
3695 command. See the user manual for more details on this command.
3697 * When natively debugging programs on PowerPC BookE processors running
3698 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3699 which stop execution of the inferior whenever it executes an instruction
3700 at any address within the specified range. See the "PowerPC Embedded"
3701 section in the user manual for more details.
3703 * New features in the GDB remote stub, GDBserver
3705 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3706 and i686 LynxOS (version 5.x).
3708 ** GDBserver is now supported on Blackfin Linux.
3710 * New native configurations
3712 ia64 HP-UX ia64-*-hpux*
3716 Analog Devices, Inc. Blackfin Processor bfin-*
3718 * Ada task switching is now supported on sparc-elf targets when
3719 debugging a program using the Ravenscar Profile. For more information,
3720 see the "Tasking Support when using the Ravenscar Profile" section
3721 in the GDB user manual.
3723 * Guile support was removed.
3725 * New features in the GNU simulator
3727 ** The --map-info flag lists all known core mappings.
3729 ** CFI flashes may be simulated via the "cfi" device.
3731 *** Changes in GDB 7.2
3733 * Shared library support for remote targets by default
3735 When GDB is configured for a generic, non-OS specific target, like
3736 for example, --target=arm-eabi or one of the many *-*-elf targets,
3737 GDB now queries remote stubs for loaded shared libraries using the
3738 `qXfer:libraries:read' packet. Previously, shared library support
3739 was always disabled for such configurations.
3743 ** Argument Dependent Lookup (ADL)
3745 In C++ ADL lookup directs function search to the namespaces of its
3746 arguments even if the namespace has not been imported.
3756 Here the compiler will search for `foo' in the namespace of 'b'
3757 and find A::foo. GDB now supports this. This construct is commonly
3758 used in the Standard Template Library for operators.
3760 ** Improved User Defined Operator Support
3762 In addition to member operators, GDB now supports lookup of operators
3763 defined in a namespace and imported with a `using' directive, operators
3764 defined in the global scope, operators imported implicitly from an
3765 anonymous namespace, and the ADL operators mentioned in the previous
3767 GDB now also supports proper overload resolution for all the previously
3768 mentioned flavors of operators.
3770 ** static const class members
3772 Printing of static const class members that are initialized in the
3773 class definition has been fixed.
3775 * Windows Thread Information Block access.
3777 On Windows targets, GDB now supports displaying the Windows Thread
3778 Information Block (TIB) structure. This structure is visible either
3779 by using the new command `info w32 thread-information-block' or, by
3780 dereferencing the new convenience variable named `$_tlb', a
3781 thread-specific pointer to the TIB. This feature is also supported
3782 when remote debugging using GDBserver.
3784 * Static tracepoints
3786 Static tracepoints are calls in the user program into a tracing
3787 library. One such library is a port of the LTTng kernel tracer to
3788 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3789 When debugging with GDBserver, GDB now supports combining the GDB
3790 tracepoint machinery with such libraries. For example: the user can
3791 use GDB to probe a static tracepoint marker (a call from the user
3792 program into the tracing library) with the new "strace" command (see
3793 "New commands" below). This creates a "static tracepoint" in the
3794 breakpoint list, that can be manipulated with the same feature set
3795 as fast and regular tracepoints. E.g., collect registers, local and
3796 global variables, collect trace state variables, and define
3797 tracepoint conditions. In addition, the user can collect extra
3798 static tracepoint marker specific data, by collecting the new
3799 $_sdata internal variable. When analyzing the trace buffer, you can
3800 inspect $_sdata like any other variable available to GDB. For more
3801 information, see the "Tracepoints" chapter in GDB user manual. New
3802 remote packets have been defined to support static tracepoints, see
3803 the "New remote packets" section below.
3805 * Better reconstruction of tracepoints after disconnected tracing
3807 GDB will attempt to download the original source form of tracepoint
3808 definitions when starting a trace run, and then will upload these
3809 upon reconnection to the target, resulting in a more accurate
3810 reconstruction of the tracepoints that are in use on the target.
3814 You can now exercise direct control over the ways that GDB can
3815 affect your program. For instance, you can disallow the setting of
3816 breakpoints, so that the program can run continuously (assuming
3817 non-stop mode). In addition, the "observer" variable is available
3818 to switch all of the different controls; in observer mode, GDB
3819 cannot affect the target's behavior at all, which is useful for
3820 tasks like diagnosing live systems in the field.
3822 * The new convenience variable $_thread holds the number of the
3825 * New remote packets
3829 Return the address of the Windows Thread Information Block of a given thread.
3833 In response to several of the tracepoint packets, the target may now
3834 also respond with a number of intermediate `qRelocInsn' request
3835 packets before the final result packet, to have GDB handle
3836 relocating an instruction to execute at a different address. This
3837 is particularly useful for stubs that support fast tracepoints. GDB
3838 reports support for this feature in the qSupported packet.
3842 List static tracepoint markers in the target program.
3846 List static tracepoint markers at a given address in the target
3849 qXfer:statictrace:read
3851 Read the static trace data collected (by a `collect $_sdata'
3852 tracepoint action). The remote stub reports support for this packet
3853 to gdb's qSupported query.
3857 Send the current settings of GDB's permission flags.
3861 Send part of the source (textual) form of a tracepoint definition,
3862 which includes location, conditional, and action list.
3864 * The source command now accepts a -s option to force searching for the
3865 script in the source search path even if the script name specifies
3868 * New features in the GDB remote stub, GDBserver
3870 - GDBserver now support tracepoints (including fast tracepoints, and
3871 static tracepoints). The feature is currently supported by the
3872 i386-linux and amd64-linux builds. See the "Tracepoints support
3873 in gdbserver" section in the manual for more information.
3875 GDBserver JIT compiles the tracepoint's conditional agent
3876 expression bytecode into native code whenever possible for low
3877 overhead dynamic tracepoints conditionals. For such tracepoints,
3878 an expression that examines program state is evaluated when the
3879 tracepoint is reached, in order to determine whether to capture
3880 trace data. If the condition is simple and false, processing the
3881 tracepoint finishes very quickly and no data is gathered.
3883 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3884 for static tracepoints support.
3886 - GDBserver now supports x86_64 Windows 64-bit debugging.
3888 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3889 it understands register description.
3891 * The --batch flag now disables pagination and queries.
3893 * X86 general purpose registers
3895 GDB now supports reading/writing byte, word and double-word x86
3896 general purpose registers directly. This means you can use, say,
3897 $ah or $ax to refer, respectively, to the byte register AH and
3898 16-bit word register AX that are actually portions of the 32-bit
3899 register EAX or 64-bit register RAX.
3901 * The `commands' command now accepts a range of breakpoints to modify.
3902 A plain `commands' following a command that creates multiple
3903 breakpoints affects all the breakpoints set by that command. This
3904 applies to breakpoints set by `rbreak', and also applies when a
3905 single `break' command creates multiple breakpoints (e.g.,
3906 breakpoints on overloaded c++ functions).
3908 * The `rbreak' command now accepts a filename specification as part of
3909 its argument, limiting the functions selected by the regex to those
3910 in the specified file.
3912 * Support for remote debugging Windows and SymbianOS shared libraries
3913 from Unix hosts has been improved. Non Windows GDB builds now can
3914 understand target reported file names that follow MS-DOS based file
3915 system semantics, such as file names that include drive letters and
3916 use the backslash character as directory separator. This makes it
3917 possible to transparently use the "set sysroot" and "set
3918 solib-search-path" on Unix hosts to point as host copies of the
3919 target's shared libraries. See the new command "set
3920 target-file-system-kind" described below, and the "Commands to
3921 specify files" section in the user manual for more information.
3925 eval template, expressions...
3926 Convert the values of one or more expressions under the control
3927 of the string template to a command line, and call it.
3929 set target-file-system-kind unix|dos-based|auto
3930 show target-file-system-kind
3931 Set or show the assumed file system kind for target reported file
3934 save breakpoints <filename>
3935 Save all current breakpoint definitions to a file suitable for use
3936 in a later debugging session. To read the saved breakpoint
3937 definitions, use the `source' command.
3939 `save tracepoints' is a new alias for `save-tracepoints'. The latter
3942 info static-tracepoint-markers
3943 Display information about static tracepoint markers in the target.
3945 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
3946 Define a static tracepoint by probing a marker at the given
3947 function, line, address, or marker ID.
3951 Enable and disable observer mode.
3953 set may-write-registers on|off
3954 set may-write-memory on|off
3955 set may-insert-breakpoints on|off
3956 set may-insert-tracepoints on|off
3957 set may-insert-fast-tracepoints on|off
3958 set may-interrupt on|off
3959 Set individual permissions for GDB effects on the target. Note that
3960 some of these settings can have undesirable or surprising
3961 consequences, particularly when changed in the middle of a session.
3962 For instance, disabling the writing of memory can prevent
3963 breakpoints from being inserted, cause single-stepping to fail, or
3964 even crash your program, if you disable after breakpoints have been
3965 inserted. However, GDB should not crash.
3967 set record memory-query on|off
3968 show record memory-query
3969 Control whether to stop the inferior if memory changes caused
3970 by an instruction cannot be recorded.
3975 The disassemble command now supports "start,+length" form of two arguments.
3979 ** GDB now provides a new directory location, called the python directory,
3980 where Python scripts written for GDB can be installed. The location
3981 of that directory is <data-directory>/python, where <data-directory>
3982 is the GDB data directory. For more details, see section `Scripting
3983 GDB using Python' in the manual.
3985 ** The GDB Python API now has access to breakpoints, symbols, symbol
3986 tables, program spaces, inferiors, threads and frame's code blocks.
3987 Additionally, GDB Parameters can now be created from the API, and
3988 manipulated via set/show in the CLI.
3990 ** New functions gdb.target_charset, gdb.target_wide_charset,
3991 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3993 ** New exception gdb.GdbError.
3995 ** Pretty-printers are now also looked up in the current program space.
3997 ** Pretty-printers can now be individually enabled and disabled.
3999 ** GDB now looks for names of Python scripts to auto-load in a
4000 special section named `.debug_gdb_scripts', in addition to looking
4001 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
4003 * Tracepoint actions were unified with breakpoint commands. In particular,
4004 there are no longer differences in "info break" output for breakpoints and
4005 tracepoints and the "commands" command can be used for both tracepoints and
4006 regular breakpoints.
4010 ARM Symbian arm*-*-symbianelf*
4012 * D language support.
4013 GDB now supports debugging programs written in the D programming
4016 * GDB now supports the extended ptrace interface for PowerPC which is
4017 available since Linux kernel version 2.6.34. This automatically enables
4018 any hardware breakpoints and additional hardware watchpoints available in
4019 the processor. The old ptrace interface exposes just one hardware
4020 watchpoint and no hardware breakpoints.
4022 * GDB is now able to use the Data Value Compare (DVC) register available on
4023 embedded PowerPC processors to implement in hardware simple watchpoint
4024 conditions of the form:
4026 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
4028 This works in native GDB running on Linux kernels with the extended ptrace
4029 interface mentioned above.
4031 *** Changes in GDB 7.1
4035 ** Namespace Support
4037 GDB now supports importing of namespaces in C++. This enables the
4038 user to inspect variables from imported namespaces. Support for
4039 namepace aliasing has also been added. So, if a namespace is
4040 aliased in the current scope (e.g. namepace C=A; ) the user can
4041 print variables using the alias (e.g. (gdb) print C::x).
4045 All known bugs relating to the printing of virtual base class were
4046 fixed. It is now possible to call overloaded static methods using a
4051 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
4052 and reinterpret_cast<> are now handled by the C++ expression parser.
4056 Xilinx MicroBlaze microblaze-*-*
4061 Xilinx MicroBlaze microblaze
4064 * Multi-program debugging.
4066 GDB now has support for multi-program (a.k.a. multi-executable or
4067 multi-exec) debugging. This allows for debugging multiple inferiors
4068 simultaneously each running a different program under the same GDB
4069 session. See "Debugging Multiple Inferiors and Programs" in the
4070 manual for more information. This implied some user visible changes
4071 in the multi-inferior support. For example, "info inferiors" now
4072 lists inferiors that are not running yet or that have exited
4073 already. See also "New commands" and "New options" below.
4075 * New tracing features
4077 GDB's tracepoint facility now includes several new features:
4079 ** Trace state variables
4081 GDB tracepoints now include support for trace state variables, which
4082 are variables managed by the target agent during a tracing
4083 experiment. They are useful for tracepoints that trigger each
4084 other, so for instance one tracepoint can count hits in a variable,
4085 and then a second tracepoint has a condition that is true when the
4086 count reaches a particular value. Trace state variables share the
4087 $-syntax of GDB convenience variables, and can appear in both
4088 tracepoint actions and condition expressions. Use the "tvariable"
4089 command to create, and "info tvariables" to view; see "Trace State
4090 Variables" in the manual for more detail.
4094 GDB now includes an option for defining fast tracepoints, which
4095 targets may implement more efficiently, such as by installing a jump
4096 into the target agent rather than a trap instruction. The resulting
4097 speedup can be by two orders of magnitude or more, although the
4098 tradeoff is that some program locations on some target architectures
4099 might not allow fast tracepoint installation, for instance if the
4100 instruction to be replaced is shorter than the jump. To request a
4101 fast tracepoint, use the "ftrace" command, with syntax identical to
4102 the regular trace command.
4104 ** Disconnected tracing
4106 It is now possible to detach GDB from the target while it is running
4107 a trace experiment, then reconnect later to see how the experiment
4108 is going. In addition, a new variable disconnected-tracing lets you
4109 tell the target agent whether to continue running a trace if the
4110 connection is lost unexpectedly.
4114 GDB now has the ability to save the trace buffer into a file, and
4115 then use that file as a target, similarly to you can do with
4116 corefiles. You can select trace frames, print data that was
4117 collected in them, and use tstatus to display the state of the
4118 tracing run at the moment that it was saved. To create a trace
4119 file, use "tsave <filename>", and to use it, do "target tfile
4122 ** Circular trace buffer
4124 You can ask the target agent to handle the trace buffer as a
4125 circular buffer, discarding the oldest trace frames to make room for
4126 newer ones, by setting circular-trace-buffer to on. This feature may
4127 not be available for all target agents.
4132 The disassemble command, when invoked with two arguments, now requires
4133 the arguments to be comma-separated.
4136 The info variables command now displays variable definitions. Files
4137 which only declare a variable are not shown.
4140 The source command is now capable of sourcing Python scripts.
4141 This feature is dependent on the debugger being build with Python
4144 Related to this enhancement is also the introduction of a new command
4145 "set script-extension" (see below).
4147 * New commands (for set/show, see "New options" below)
4149 record save [<FILENAME>]
4150 Save a file (in core file format) containing the process record
4151 execution log for replay debugging at a later time.
4153 record restore <FILENAME>
4154 Restore the process record execution log that was saved at an
4155 earlier time, for replay debugging.
4157 add-inferior [-copies <N>] [-exec <FILENAME>]
4160 clone-inferior [-copies <N>] [ID]
4161 Make a new inferior ready to execute the same program another
4162 inferior has loaded.
4167 maint info program-spaces
4168 List the program spaces loaded into GDB.
4170 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
4171 show remote interrupt-sequence
4172 Allow the user to select one of ^C, a BREAK signal or BREAK-g
4173 as the sequence to the remote target in order to interrupt the execution.
4174 Ctrl-C is a default. Some system prefers BREAK which is high level of
4175 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
4176 Magic SysRq g. It is BREAK signal and character 'g'.
4178 set remote interrupt-on-connect [on | off]
4179 show remote interrupt-on-connect
4180 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
4181 remote target when gdb connects to it. This is needed when you debug
4184 set remotebreak [on | off]
4186 Deprecated. Use "set/show remote interrupt-sequence" instead.
4188 tvariable $NAME [ = EXP ]
4189 Create or modify a trace state variable.
4192 List trace state variables and their values.
4194 delete tvariable $NAME ...
4195 Delete one or more trace state variables.
4198 Evaluate the given expressions without collecting anything into the
4199 trace buffer. (Valid in tracepoint actions only.)
4201 ftrace FN / FILE:LINE / *ADDR
4202 Define a fast tracepoint at the given function, line, or address.
4204 * New expression syntax
4206 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
4207 GDB now parses 0b101010 identically with 42.
4211 set follow-exec-mode new|same
4212 show follow-exec-mode
4213 Control whether GDB reuses the same inferior across an exec call or
4214 creates a new one. This is useful to be able to restart the old
4215 executable after the inferior having done an exec call.
4217 set default-collect EXPR, ...
4218 show default-collect
4219 Define a list of expressions to be collected at each tracepoint.
4220 This is a useful way to ensure essential items are not overlooked,
4221 such as registers or a critical global variable.
4223 set disconnected-tracing
4224 show disconnected-tracing
4225 If set to 1, the target is instructed to continue tracing if it
4226 loses its connection to GDB. If 0, the target is to stop tracing
4229 set circular-trace-buffer
4230 show circular-trace-buffer
4231 If set to on, the target is instructed to use a circular trace buffer
4232 and discard the oldest trace frames instead of stopping the trace due
4233 to a full trace buffer. If set to off, the trace stops when the buffer
4234 fills up. Some targets may not support this.
4236 set script-extension off|soft|strict
4237 show script-extension
4238 If set to "off", the debugger does not perform any script language
4239 recognition, and all sourced files are assumed to be GDB scripts.
4240 If set to "soft" (the default), files are sourced according to
4241 filename extension, falling back to GDB scripts if the first
4243 If set to "strict", files are sourced according to filename extension.
4245 set ada trust-PAD-over-XVS on|off
4246 show ada trust-PAD-over-XVS
4247 If off, activate a workaround against a bug in the debugging information
4248 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
4249 the GCC sources for more information about the GNAT encoding and
4250 PAD types in particular). It is always safe to set this option to
4251 off, but this introduces a slight performance penalty. The default
4254 * Python API Improvements
4256 ** GDB provides the new class gdb.LazyString. This is useful in
4257 some pretty-printing cases. The new method gdb.Value.lazy_string
4258 provides a simple way to create objects of this type.
4260 ** The fields returned by gdb.Type.fields now have an
4261 `is_base_class' attribute.
4263 ** The new method gdb.Type.range returns the range of an array type.
4265 ** The new method gdb.parse_and_eval can be used to parse and
4266 evaluate an expression.
4268 * New remote packets
4271 Define a trace state variable.
4274 Get the current value of a trace state variable.
4277 Set desired tracing behavior upon disconnection.
4280 Set the trace buffer to be linear or circular.
4283 Get data about the tracepoints currently in use.
4287 Process record now works correctly with hardware watchpoints.
4289 Multiple bug fixes have been made to the mips-irix port, making it
4290 much more reliable. In particular:
4291 - Debugging threaded applications is now possible again. Previously,
4292 GDB would hang while starting the program, or while waiting for
4293 the program to stop at a breakpoint.
4294 - Attaching to a running process no longer hangs.
4295 - An error occurring while loading a core file has been fixed.
4296 - Changing the value of the PC register now works again. This fixes
4297 problems observed when using the "jump" command, or when calling
4298 a function from GDB, or even when assigning a new value to $pc.
4299 - With the "finish" and "return" commands, the return value for functions
4300 returning a small array is now correctly printed.
4301 - It is now possible to break on shared library code which gets executed
4302 during a shared library init phase (code executed while executing
4303 their .init section). Previously, the breakpoint would have no effect.
4304 - GDB is now able to backtrace through the signal handler for
4305 non-threaded programs.
4307 PIE (Position Independent Executable) programs debugging is now supported.
4308 This includes debugging execution of PIC (Position Independent Code) shared
4309 libraries although for that, it should be possible to run such libraries as an
4312 *** Changes in GDB 7.0
4314 * GDB now has an interface for JIT compilation. Applications that
4315 dynamically generate code can create symbol files in memory and register
4316 them with GDB. For users, the feature should work transparently, and
4317 for JIT developers, the interface is documented in the GDB manual in the
4318 "JIT Compilation Interface" chapter.
4320 * Tracepoints may now be conditional. The syntax is as for
4321 breakpoints; either an "if" clause appended to the "trace" command,
4322 or the "condition" command is available. GDB sends the condition to
4323 the target for evaluation using the same bytecode format as is used
4324 for tracepoint actions.
4326 * The disassemble command now supports: an optional /r modifier, print the
4327 raw instructions in hex as well as in symbolic form, and an optional /m
4328 modifier to print mixed source+assembly.
4330 * Process record and replay
4332 In a architecture environment that supports ``process record and
4333 replay'', ``process record and replay'' target can record a log of
4334 the process execution, and replay it with both forward and reverse
4337 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
4338 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
4339 set execution-direction {forward|reverse}, for targets that support
4342 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
4343 feature is available with a native GDB running on kernel version
4346 * GDB now has support for multi-byte and wide character sets on the
4347 target. Strings whose character type is wchar_t, char16_t, or
4348 char32_t are now correctly printed. GDB supports wide- and unicode-
4349 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
4350 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
4351 `printf'. This feature requires iconv to work properly; if your
4352 system does not have a working iconv, GDB can use GNU libiconv. See
4353 the installation instructions for more information.
4355 * GDB now supports automatic retrieval of shared library files from
4356 remote targets. To use this feature, specify a system root that begins
4357 with the `remote:' prefix, either via the `set sysroot' command or via
4358 the `--with-sysroot' configure-time option.
4360 * "info sharedlibrary" now takes an optional regex of libraries to show,
4361 and it now reports if a shared library has no debugging information.
4363 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
4364 now complete on file names.
4366 * When completing in expressions, gdb will attempt to limit
4367 completions to allowable structure or union fields, where appropriate.
4368 For instance, consider:
4370 # struct example { int f1; double f2; };
4371 # struct example variable;
4374 If the user types TAB at the end of this command line, the available
4375 completions will be "f1" and "f2".
4377 * Inlined functions are now supported. They show up in backtraces, and
4378 the "step", "next", and "finish" commands handle them automatically.
4380 * GDB now supports the token-splicing (##) and stringification (#)
4381 operators when expanding macros. It also supports variable-arity
4384 * GDB now supports inspecting extra signal information, exported by
4385 the new $_siginfo convenience variable. The feature is currently
4386 implemented on linux ARM, i386 and amd64.
4388 * GDB can now display the VFP floating point registers and NEON vector
4389 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
4390 can provide these registers (requires Linux 2.6.30 or later). Remote
4391 and simulator targets may also provide them.
4393 * New remote packets
4396 Search memory for a sequence of bytes.
4399 Turn off `+'/`-' protocol acknowledgments to permit more efficient
4400 operation over reliable transport links. Use of this packet is
4401 controlled by the `set remote noack-packet' command.
4404 Kill the process with the specified process ID. Use this in preference
4405 to `k' when multiprocess protocol extensions are supported.
4408 Obtains additional operating system information
4412 Read or write additional signal information.
4414 * Removed remote protocol undocumented extension
4416 An undocumented extension to the remote protocol's `S' stop reply
4417 packet that permitted the stub to pass a process id was removed.
4418 Remote servers should use the `T' stop reply packet instead.
4420 * GDB now supports multiple function calling conventions according to the
4421 DWARF-2 DW_AT_calling_convention function attribute.
4423 * The SH target utilizes the aforementioned change to distinguish between gcc
4424 and Renesas calling convention. It also adds the new CLI commands
4425 `set/show sh calling-convention'.
4427 * GDB can now read compressed debug sections, as produced by GNU gold
4428 with the --compress-debug-sections=zlib flag.
4430 * 64-bit core files are now supported on AIX.
4432 * Thread switching is now supported on Tru64.
4434 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
4435 which will be allocated using malloc later in program execution.
4437 * The qXfer:libraries:read remote protocol packet now allows passing a
4438 list of section offsets.
4440 * On GNU/Linux, GDB can now attach to stopped processes. Several race
4441 conditions handling signals delivered during attach or thread creation
4442 have also been fixed.
4444 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
4445 From the user's standpoint, all unqualified instances of True and False
4446 are treated as the standard definitions, regardless of context.
4448 * GDB now parses C++ symbol and type names more flexibly. For
4451 template<typename T> class C { };
4454 GDB will now correctly handle all of:
4456 ptype C<char const *>
4457 ptype C<char const*>
4458 ptype C<const char *>
4459 ptype C<const char*>
4461 * New features in the GDB remote stub, gdbserver
4463 - The "--wrapper" command-line argument tells gdbserver to use a
4464 wrapper program to launch programs for debugging.
4466 - On PowerPC and S/390 targets, it is now possible to use a single
4467 gdbserver executable to debug both 32-bit and 64-bit programs.
4468 (This requires gdbserver itself to be built as a 64-bit executable.)
4470 - gdbserver uses the new noack protocol mode for TCP connections to
4471 reduce communications latency, if also supported and enabled in GDB.
4473 - Support for the sparc64-linux-gnu target is now included in
4476 - The amd64-linux build of gdbserver now supports debugging both
4477 32-bit and 64-bit programs.
4479 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
4480 now support hardware watchpoints, and will use them automatically
4485 GDB now has support for scripting using Python. Whether this is
4486 available is determined at configure time.
4488 New GDB commands can now be written in Python.
4490 * Ada tasking support
4492 Ada tasks can now be inspected in GDB. The following commands have
4496 Print the list of Ada tasks.
4498 Print detailed information about task number N.
4500 Print the task number of the current task.
4502 Switch the context of debugging to task number N.
4504 * Support for user-defined prefixed commands. The "define" command can
4505 add new commands to existing prefixes, e.g. "target".
4507 * Multi-inferior, multi-process debugging.
4509 GDB now has generalized support for multi-inferior debugging. See
4510 "Debugging Multiple Inferiors" in the manual for more information.
4511 Although availability still depends on target support, the command
4512 set is more uniform now. The GNU/Linux specific multi-forks support
4513 has been migrated to this new framework. This implied some user
4514 visible changes; see "New commands" and also "Removed commands"
4517 * Target descriptions can now describe the target OS ABI. See the
4518 "Target Description Format" section in the user manual for more
4521 * Target descriptions can now describe "compatible" architectures
4522 to indicate that the target can execute applications for a different
4523 architecture in addition to those for the main target architecture.
4524 See the "Target Description Format" section in the user manual for
4527 * Multi-architecture debugging.
4529 GDB now includes general supports for debugging applications on
4530 hybrid systems that use more than one single processor architecture
4531 at the same time. Each such hybrid architecture still requires
4532 specific support to be added. The only hybrid architecture supported
4533 in this version of GDB is the Cell Broadband Engine.
4535 * GDB now supports integrated debugging of Cell/B.E. applications that
4536 use both the PPU and SPU architectures. To enable support for hybrid
4537 Cell/B.E. debugging, you need to configure GDB to support both the
4538 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
4539 --enable-targets configure option.
4541 * Non-stop mode debugging.
4543 For some targets, GDB now supports an optional mode of operation in
4544 which you can examine stopped threads while other threads continue
4545 to execute freely. This is referred to as non-stop mode, with the
4546 old mode referred to as all-stop mode. See the "Non-Stop Mode"
4547 section in the user manual for more information.
4549 To be able to support remote non-stop debugging, a remote stub needs
4550 to implement the non-stop mode remote protocol extensions, as
4551 described in the "Remote Non-Stop" section of the user manual. The
4552 GDB remote stub, gdbserver, has been adjusted to support these
4553 extensions on linux targets.
4555 * New commands (for set/show, see "New options" below)
4557 catch syscall [NAME(S) | NUMBER(S)]
4558 Catch system calls. Arguments, which should be names of system
4559 calls or their numbers, mean catch only those syscalls. Without
4560 arguments, every syscall will be caught. When the inferior issues
4561 any of the specified syscalls, GDB will stop and announce the system
4562 call, both when it is called and when its call returns. This
4563 feature is currently available with a native GDB running on the
4564 Linux Kernel, under the following architectures: x86, x86_64,
4565 PowerPC and PowerPC64.
4567 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
4569 Search memory for a sequence of bytes.
4571 maint set python print-stack
4572 maint show python print-stack
4573 Show a stack trace when an error is encountered in a Python script.
4576 Invoke CODE by passing it to the Python interpreter.
4581 These allow macros to be defined, undefined, and listed
4585 Show operating system information about processes.
4588 List the inferiors currently under GDB's control.
4591 Switch focus to inferior number NUM.
4594 Detach from inferior number NUM.
4597 Kill inferior number NUM.
4601 set spu stop-on-load
4602 show spu stop-on-load
4603 Control whether to stop for new SPE threads during Cell/B.E. debugging.
4605 set spu auto-flush-cache
4606 show spu auto-flush-cache
4607 Control whether to automatically flush the software-managed cache
4608 during Cell/B.E. debugging.
4610 set sh calling-convention
4611 show sh calling-convention
4612 Control the calling convention used when calling SH target functions.
4615 show debug timestamp
4616 Control display of timestamps with GDB debugging output.
4618 set disassemble-next-line
4619 show disassemble-next-line
4620 Control display of disassembled source lines or instructions when
4623 set remote noack-packet
4624 show remote noack-packet
4625 Set/show the use of remote protocol QStartNoAckMode packet. See above
4626 under "New remote packets."
4628 set remote query-attached-packet
4629 show remote query-attached-packet
4630 Control use of remote protocol `qAttached' (query-attached) packet.
4632 set remote read-siginfo-object
4633 show remote read-siginfo-object
4634 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4637 set remote write-siginfo-object
4638 show remote write-siginfo-object
4639 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4642 set remote reverse-continue
4643 show remote reverse-continue
4644 Control use of remote protocol 'bc' (reverse-continue) packet.
4646 set remote reverse-step
4647 show remote reverse-step
4648 Control use of remote protocol 'bs' (reverse-step) packet.
4650 set displaced-stepping
4651 show displaced-stepping
4652 Control displaced stepping mode. Displaced stepping is a way to
4653 single-step over breakpoints without removing them from the debuggee.
4654 Also known as "out-of-line single-stepping".
4657 show debug displaced
4658 Control display of debugging info for displaced stepping.
4660 maint set internal-error
4661 maint show internal-error
4662 Control what GDB does when an internal error is detected.
4664 maint set internal-warning
4665 maint show internal-warning
4666 Control what GDB does when an internal warning is detected.
4671 Use a wrapper program to launch programs for debugging.
4673 set multiple-symbols (all|ask|cancel)
4674 show multiple-symbols
4675 The value of this variable can be changed to adjust the debugger behavior
4676 when an expression or a breakpoint location contains an ambiguous symbol
4677 name (an overloaded function name, for instance).
4679 set breakpoint always-inserted
4680 show breakpoint always-inserted
4681 Keep breakpoints always inserted in the target, as opposed to inserting
4682 them when resuming the target, and removing them when the target stops.
4683 This option can improve debugger performance on slow remote targets.
4685 set arm fallback-mode (arm|thumb|auto)
4686 show arm fallback-mode
4687 set arm force-mode (arm|thumb|auto)
4689 These commands control how ARM GDB determines whether instructions
4690 are ARM or Thumb. The default for both settings is auto, which uses
4691 the current CPSR value for instructions without symbols; previous
4692 versions of GDB behaved as if "set arm fallback-mode arm".
4694 set disable-randomization
4695 show disable-randomization
4696 Standalone programs run with the virtual address space randomization enabled
4697 by default on some platforms. This option keeps the addresses stable across
4698 multiple debugging sessions.
4702 Control whether other threads are stopped or not when some thread hits
4707 Requests that asynchronous execution is enabled in the target, if available.
4708 In this case, it's possible to resume target in the background, and interact
4709 with GDB while the target is running. "show target-async" displays the
4710 current state of asynchronous execution of the target.
4712 set target-wide-charset
4713 show target-wide-charset
4714 The target-wide-charset is the name of the character set that GDB
4715 uses when printing characters whose type is wchar_t.
4717 set tcp auto-retry (on|off)
4719 set tcp connect-timeout
4720 show tcp connect-timeout
4721 These commands allow GDB to retry failed TCP connections to a remote stub
4722 with a specified timeout period; this is useful if the stub is launched
4723 in parallel with GDB but may not be ready to accept connections immediately.
4725 set libthread-db-search-path
4726 show libthread-db-search-path
4727 Control list of directories which GDB will search for appropriate
4730 set schedule-multiple (on|off)
4731 show schedule-multiple
4732 Allow GDB to resume all threads of all processes or only threads of
4733 the current process.
4737 Use more aggressive caching for accesses to the stack. This improves
4738 performance of remote debugging (particularly backtraces) without
4739 affecting correctness.
4741 set interactive-mode (on|off|auto)
4742 show interactive-mode
4743 Control whether GDB runs in interactive mode (on) or not (off).
4744 When in interactive mode, GDB waits for the user to answer all
4745 queries. Otherwise, GDB does not wait and assumes the default
4746 answer. When set to auto (the default), GDB determines which
4747 mode to use based on the stdin settings.
4752 For program forks, this is replaced by the new more generic `info
4753 inferiors' command. To list checkpoints, you can still use the
4754 `info checkpoints' command, which was an alias for the `info forks'
4758 Replaced by the new `inferior' command. To switch between
4759 checkpoints, you can still use the `restart' command, which was an
4760 alias for the `fork' command.
4763 This is removed, since some targets don't have a notion of
4764 processes. To switch between processes, you can still use the
4765 `inferior' command using GDB's own inferior number.
4768 For program forks, this is replaced by the new more generic `kill
4769 inferior' command. To delete a checkpoint, you can still use the
4770 `delete checkpoint' command, which was an alias for the `delete
4774 For program forks, this is replaced by the new more generic `detach
4775 inferior' command. To detach a checkpoint, you can still use the
4776 `detach checkpoint' command, which was an alias for the `detach
4779 * New native configurations
4781 x86/x86_64 Darwin i[34567]86-*-darwin*
4783 x86_64 MinGW x86_64-*-mingw*
4787 Lattice Mico32 lm32-*
4788 x86 DICOS i[34567]86-*-dicos*
4789 x86_64 DICOS x86_64-*-dicos*
4792 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4793 (mingw32ce) debugging.
4799 These commands were actually not implemented on any target.
4801 *** Changes in GDB 6.8
4803 * New native configurations
4805 NetBSD/hppa hppa*-*netbsd*
4806 Xtensa GNU/Linux xtensa*-*-linux*
4810 NetBSD/hppa hppa*-*-netbsd*
4811 Xtensa GNU/Linux xtensa*-*-linux*
4813 * Change in command line behavior -- corefiles vs. process ids.
4815 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4816 attaching to process NUMBER fails, GDB no longer attempts to open a
4817 core file named NUMBER. Attaching to a program using the -c option
4818 is no longer supported. Instead, use the '-p' or '--pid' options.
4820 * GDB can now be built as a native debugger for debugging Windows x86
4821 (mingw32) Portable Executable (PE) programs.
4823 * Pending breakpoints no longer change their number when their address
4826 * GDB now supports breakpoints with multiple locations,
4827 including breakpoints on C++ constructors, inside C++ templates,
4828 and in inlined functions.
4830 * GDB's ability to debug optimized code has been improved. GDB more
4831 accurately identifies function bodies and lexical blocks that occupy
4832 more than one contiguous range of addresses.
4834 * Target descriptions can now describe registers for PowerPC.
4836 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4837 registers on PowerPC targets.
4839 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4840 targets even when the libthread_db library is not available.
4842 * The GDB remote stub, gdbserver, now supports the new file transfer
4843 commands (remote put, remote get, and remote delete).
4845 * The GDB remote stub, gdbserver, now supports run and attach in
4846 extended-remote mode.
4848 * hppa*64*-*-hpux11* target broken
4849 The debugger is unable to start a program and fails with the following
4850 error: "Error trying to get information about dynamic linker".
4851 The gdb-6.7 release is also affected.
4853 * GDB now supports the --enable-targets= configure option to allow
4854 building a single GDB executable that supports multiple remote
4855 target architectures.
4857 * GDB now supports debugging C and C++ programs which use the
4858 Decimal Floating Point extension. In addition, the PowerPC target
4859 now has a set of pseudo-registers to inspect decimal float values
4860 stored in two consecutive float registers.
4862 * The -break-insert MI command can optionally create pending
4865 * Improved support for debugging Ada
4866 Many improvements to the Ada language support have been made. These
4868 - Better support for Ada2005 interface types
4869 - Improved handling of arrays and slices in general
4870 - Better support for Taft-amendment types
4871 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4873 - Improved command completion in Ada
4876 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4881 set print frame-arguments (all|scalars|none)
4882 show print frame-arguments
4883 The value of this variable can be changed to control which argument
4884 values should be printed by the debugger when displaying a frame.
4889 Transfer files to and from a remote target, and delete remote files.
4896 Transfer files to and from a remote target, and delete remote files.
4898 * New remote packets
4905 Open, close, read, write, and delete files on the remote system.
4908 Attach to an existing process on the remote system, in extended-remote
4912 Run a new process on the remote system, in extended-remote mode.
4914 *** Changes in GDB 6.7
4916 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
4917 bfd, libiberty and opcodes, as revealed by static analysis donated by
4918 Coverity, Inc. (http://scan.coverity.com).
4920 * When looking up multiply-defined global symbols, GDB will now prefer the
4921 symbol definition in the current shared library if it was built using the
4922 -Bsymbolic linker option.
4924 * When the Text User Interface (TUI) is not configured, GDB will now
4925 recognize the -tui command-line option and print a message that the TUI
4928 * The GDB remote stub, gdbserver, now has lower overhead for high
4929 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
4931 * GDB for MIPS targets now autodetects whether a remote target provides
4932 32-bit or 64-bit register values.
4934 * Support for C++ member pointers has been improved.
4936 * GDB now understands XML target descriptions, which specify the
4937 target's overall architecture. GDB can read a description from
4938 a local file or over the remote serial protocol.
4940 * Vectors of single-byte data use a new integer type which is not
4941 automatically displayed as character or string data.
4943 * The /s format now works with the print command. It displays
4944 arrays of single-byte integers and pointers to single-byte integers
4947 * Target descriptions can now describe target-specific registers,
4948 for architectures which have implemented the support (currently
4949 only ARM, M68K, and MIPS).
4951 * GDB and the GDB remote stub, gdbserver, now support the XScale
4954 * The GDB remote stub, gdbserver, has been updated to support
4955 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4956 has been rewritten to use the standard GDB remote protocol.
4958 * GDB can now step into C++ functions which are called through thunks.
4960 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4962 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4963 layout. It also supports a TextSeg= and DataSeg= response when only
4964 segment base addresses (rather than offsets) are available.
4966 * The /i format now outputs any trailing branch delay slot instructions
4967 immediately following the last instruction within the count specified.
4969 * The GDB remote protocol "T" stop reply packet now supports a
4970 "library" response. Combined with the new "qXfer:libraries:read"
4971 packet, this response allows GDB to debug shared libraries on targets
4972 where the operating system manages the list of loaded libraries (e.g.
4973 Windows and SymbianOS).
4975 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4976 (DLLs) on Windows and Windows CE targets.
4978 * GDB now supports a faster verification that a .debug file matches its binary
4979 according to its build-id signature, if the signature is present.
4985 Enable or disable hardware flow control (RTS/CTS) on the serial port
4986 when debugging using remote targets.
4988 set mem inaccessible-by-default
4989 show mem inaccessible-by-default
4990 If the target supplies a memory map, for instance via the remote
4991 protocol's "qXfer:memory-map:read" packet, setting this variable
4992 prevents GDB from accessing memory outside the memory map. This
4993 is useful for targets with memory mapped registers or which react
4994 badly to accesses of unmapped address space.
4996 set breakpoint auto-hw
4997 show breakpoint auto-hw
4998 If the target supplies a memory map, for instance via the remote
4999 protocol's "qXfer:memory-map:read" packet, setting this variable
5000 lets GDB use hardware breakpoints automatically for memory regions
5001 where it can not use software breakpoints. This covers both the
5002 "break" command and internal breakpoints used for other commands
5003 including "next" and "finish".
5006 catch exception unhandled
5007 Stop the program execution when Ada exceptions are raised.
5010 Stop the program execution when an Ada assertion failed.
5014 Set an alternate system root for target files. This is a more
5015 general version of "set solib-absolute-prefix", which is now
5016 an alias to "set sysroot".
5019 Provide extended SPU facility status information. This set of
5020 commands is available only when debugging the Cell/B.E. SPU
5023 * New native configurations
5025 OpenBSD/sh sh*-*openbsd*
5028 unset tdesc filename
5030 Use the specified local file as an XML target description, and do
5031 not query the target for its built-in description.
5035 OpenBSD/sh sh*-*-openbsd*
5036 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
5037 Toshiba Media Processor mep-elf
5039 * New remote packets
5042 Ignore the specified signals; pass them directly to the debugged program
5043 without stopping other threads or reporting them to GDB.
5045 qXfer:features:read:
5046 Read an XML target description from the target, which describes its
5051 Read or write contents of an spufs file on the target system. These
5052 packets are available only on the Cell/B.E. SPU architecture.
5054 qXfer:libraries:read:
5055 Report the loaded shared libraries. Combined with new "T" packet
5056 response, this packet allows GDB to debug shared libraries on
5057 targets where the operating system manages the list of loaded
5058 libraries (e.g. Windows and SymbianOS).
5062 Support for these obsolete configurations has been removed.
5070 i[34567]86-*-lynxos*
5071 i[34567]86-*-netware*
5072 i[34567]86-*-sco3.2v5*
5073 i[34567]86-*-sco3.2v4*
5075 i[34567]86-*-sysv4.2*
5078 i[34567]86-*-unixware2*
5079 i[34567]86-*-unixware*
5088 * Other removed features
5095 Various m68k-only ROM monitors.
5102 Various Renesas ROM monitors and debugging interfaces for SH and
5107 Support for a Macraigor serial interface to on-chip debugging.
5108 GDB does not directly support the newer parallel or USB
5113 A debug information format. The predecessor to DWARF 2 and
5114 DWARF 3, which are still supported.
5116 Support for the HP aCC compiler on HP-UX/PA-RISC
5118 SOM-encapsulated symbolic debugging information, automatic
5119 invocation of pxdb, and the aCC custom C++ ABI. This does not
5120 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
5121 with aCC can still be debugged on an assembly level.
5123 MIPS ".pdr" sections
5125 A MIPS-specific format used to describe stack frame layout
5126 in debugging information.
5130 GDB could work with an older version of Guile to debug
5131 the interpreter and Scheme programs running in it.
5133 set mips stack-arg-size
5134 set mips saved-gpreg-size
5136 Use "set mips abi" to control parameter passing for MIPS.
5138 *** Changes in GDB 6.6
5143 Cell Broadband Engine SPU spu-elf
5145 * GDB can now be configured as a cross-debugger targeting native Windows
5146 (mingw32) or Cygwin. It can communicate with a remote debugging stub
5147 running on a Windows system over TCP/IP to debug Windows programs.
5149 * The GDB remote stub, gdbserver, has been updated to support Windows and
5150 Cygwin debugging. Both single-threaded and multi-threaded programs are
5153 * The "set trust-readonly-sections" command works again. This command was
5154 broken in GDB 6.3, 6.4, and 6.5.
5156 * The "load" command now supports writing to flash memory, if the remote
5157 stub provides the required support.
5159 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
5160 longer requires symbolic debug information (e.g. DWARF-2).
5165 unset substitute-path
5166 show substitute-path
5167 Manage a list of substitution rules that GDB uses to rewrite the name
5168 of the directories where the sources are located. This can be useful
5169 for instance when the sources were moved to a different location
5170 between compilation and debugging.
5174 Print each CLI command as it is executed. Each command is prefixed with
5175 a number of `+' symbols representing the nesting depth.
5176 The source command now has a `-v' option to enable the same feature.
5180 The ARM Demon monitor support (RDP protocol, "target rdp").
5182 Kernel Object Display, an embedded debugging feature which only worked with
5183 an obsolete version of Cisco IOS.
5185 The 'set download-write-size' and 'show download-write-size' commands.
5187 * New remote packets
5190 Tell a stub about GDB client features, and request remote target features.
5191 The first feature implemented is PacketSize, which allows the target to
5192 specify the size of packets it can handle - to minimize the number of
5193 packets required and improve performance when connected to a remote
5197 Fetch an OS auxilliary vector from the remote stub. This packet is a
5198 more efficient replacement for qPart:auxv:read.
5200 qXfer:memory-map:read:
5201 Fetch a memory map from the remote stub, including information about
5202 RAM, ROM, and flash memory devices.
5207 Erase and program a flash memory device.
5209 * Removed remote packets
5212 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
5213 used it, and only gdbserver implemented it.
5215 *** Changes in GDB 6.5
5219 Renesas M32C/M16C m32c-elf
5221 Morpho Technologies ms1 ms1-elf
5225 init-if-undefined Initialize a convenience variable, but
5226 only if it doesn't already have a value.
5228 The following commands are presently only implemented for native GNU/Linux:
5230 checkpoint Save a snapshot of the program state.
5232 restart <n> Return the program state to a
5233 previously saved state.
5235 info checkpoints List currently saved checkpoints.
5237 delete-checkpoint <n> Delete a previously saved checkpoint.
5239 set|show detach-on-fork Tell gdb whether to detach from a newly
5240 forked process, or to keep debugging it.
5242 info forks List forks of the user program that
5243 are available to be debugged.
5245 fork <n> Switch to debugging one of several
5246 forks of the user program that are
5247 available to be debugged.
5249 delete-fork <n> Delete a fork from the list of forks
5250 that are available to be debugged (and
5251 kill the forked process).
5253 detach-fork <n> Delete a fork from the list of forks
5254 that are available to be debugged (and
5255 allow the process to continue).
5259 Morpho Technologies ms2 ms1-elf
5261 * Improved Windows host support
5263 GDB now builds as a cross debugger hosted on i686-mingw32, including
5264 native console support, and remote communications using either
5265 network sockets or serial ports.
5267 * Improved Modula-2 language support
5269 GDB can now print most types in the Modula-2 syntax. This includes:
5270 basic types, set types, record types, enumerated types, range types,
5271 pointer types and ARRAY types. Procedure var parameters are correctly
5272 printed and hexadecimal addresses and character constants are also
5273 written in the Modula-2 syntax. Best results can be obtained by using
5274 GNU Modula-2 together with the -gdwarf-2 command line option.
5278 The ARM rdi-share module.
5280 The Netware NLM debug server.
5282 *** Changes in GDB 6.4
5284 * New native configurations
5286 OpenBSD/arm arm*-*-openbsd*
5287 OpenBSD/mips64 mips64-*-openbsd*
5291 Morpho Technologies ms1 ms1-elf
5293 * New command line options
5295 --batch-silent As for --batch, but totally silent.
5296 --return-child-result The debugger will exist with the same value
5297 the child (debugged) program exited with.
5298 --eval-command COMMAND, -ex COMMAND
5299 Execute a single GDB CLI command. This may be
5300 specified multiple times and in conjunction
5301 with the --command (-x) option.
5303 * Deprecated commands removed
5305 The following commands, that were deprecated in 2000, have been
5309 set|show arm disassembly-flavor set|show arm disassembler
5310 othernames set arm disassembler
5311 set|show remotedebug set|show debug remote
5312 set|show archdebug set|show debug arch
5313 set|show eventdebug set|show debug event
5316 * New BSD user-level threads support
5318 It is now possible to debug programs using the user-level threads
5319 library on OpenBSD and FreeBSD. Currently supported (target)
5322 FreeBSD/amd64 x86_64-*-freebsd*
5323 FreeBSD/i386 i386-*-freebsd*
5324 OpenBSD/i386 i386-*-openbsd*
5326 Note that the new kernel threads libraries introduced in FreeBSD 5.x
5327 are not yet supported.
5329 * New support for Matsushita MN10300 w/sim added
5330 (Work in progress). mn10300-elf.
5332 * REMOVED configurations and files
5334 VxWorks and the XDR protocol *-*-vxworks
5335 Motorola MCORE mcore-*-*
5336 National Semiconductor NS32000 ns32k-*-*
5338 * New "set print array-indexes" command
5340 After turning this setting "on", GDB prints the index of each element
5341 when displaying arrays. The default is "off" to preserve the previous
5344 * VAX floating point support
5346 GDB now supports the not-quite-ieee VAX F and D floating point formats.
5348 * User-defined command support
5350 In addition to using $arg0..$arg9 for argument passing, it is now possible
5351 to use $argc to determine now many arguments have been passed. See the
5352 section on user-defined commands in the user manual for more information.
5354 *** Changes in GDB 6.3:
5356 * New command line option
5358 GDB now accepts -l followed by a number to set the timeout for remote
5361 * GDB works with GCC -feliminate-dwarf2-dups
5363 GDB now supports a more compact representation of DWARF-2 debug
5364 information using DW_FORM_ref_addr references. These are produced
5365 by GCC with the option -feliminate-dwarf2-dups and also by some
5366 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
5367 to use -feliminate-dwarf2-dups.
5369 * Internationalization
5371 When supported by the host system, GDB will be built with
5372 internationalization (libintl). The task of marking up the sources is
5373 continued, we're looking forward to our first translation.
5377 Initial support for debugging programs compiled with the GNAT
5378 implementation of the Ada programming language has been integrated
5379 into GDB. In this release, support is limited to expression evaluation.
5381 * New native configurations
5383 GNU/Linux/m32r m32r-*-linux-gnu
5387 GDB's remote protocol now includes support for the 'p' packet. This
5388 packet is used to fetch individual registers from a remote inferior.
5390 * END-OF-LIFE registers[] compatibility module
5392 GDB's internal register infrastructure has been completely rewritten.
5393 The new infrastructure making possible the implementation of key new
5394 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
5397 GDB 6.3 will be the last release to include the registers[]
5398 compatibility module that allowed out-of-date configurations to
5399 continue to work. This change directly impacts the following
5409 powerpc bdm protocol
5411 Unless there is activity to revive these configurations, they will be
5412 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
5414 * OBSOLETE configurations and files
5416 Configurations that have been declared obsolete in this release have
5417 been commented out. Unless there is activity to revive these
5418 configurations, the next release of GDB will have their sources
5419 permanently REMOVED.
5428 *** Changes in GDB 6.2.1:
5430 * MIPS `break main; run' gave an heuristic-fence-post warning
5432 When attempting to run even a simple program, a warning about
5433 heuristic-fence-post being hit would be reported. This problem has
5436 * MIPS IRIX 'long double' crashed GDB
5438 When examining a long double variable, GDB would get a segmentation
5439 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
5440 IRIX long double values).
5444 A bug in the VAX stack code was causing problems with the "next"
5445 command. This problem has been fixed.
5447 *** Changes in GDB 6.2:
5449 * Fix for ``many threads''
5451 On GNU/Linux systems that use the NPTL threads library, a program
5452 rapidly creating and deleting threads would confuse GDB leading to the
5455 ptrace: No such process.
5456 thread_db_get_info: cannot get thread info: generic error
5458 This problem has been fixed.
5460 * "-async" and "-noasync" options removed.
5462 Support for the broken "-noasync" option has been removed (it caused
5465 * New ``start'' command.
5467 This command runs the program until the beginning of the main procedure.
5469 * New BSD Kernel Data Access Library (libkvm) interface
5471 Using ``target kvm'' it is now possible to debug kernel core dumps and
5472 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
5473 platforms. Currently supported (native-only) configurations are:
5475 FreeBSD/amd64 x86_64-*-freebsd*
5476 FreeBSD/i386 i?86-*-freebsd*
5477 NetBSD/i386 i?86-*-netbsd*
5478 NetBSD/m68k m68*-*-netbsd*
5479 NetBSD/sparc sparc-*-netbsd*
5480 OpenBSD/amd64 x86_64-*-openbsd*
5481 OpenBSD/i386 i?86-*-openbsd*
5482 OpenBSD/m68k m68*-openbsd*
5483 OpenBSD/sparc sparc-*-openbsd*
5485 * Signal trampoline code overhauled
5487 Many generic problems with GDB's signal handling code have been fixed.
5488 These include: backtraces through non-contiguous stacks; recognition
5489 of sa_sigaction signal trampolines; backtrace from a NULL pointer
5490 call; backtrace through a signal trampoline; step into and out of
5491 signal handlers; and single-stepping in the signal trampoline.
5493 Please note that kernel bugs are a limiting factor here. These
5494 features have been shown to work on an s390 GNU/Linux system that
5495 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
5497 * Cygwin support for DWARF 2 added.
5499 * New native configurations
5501 GNU/Linux/hppa hppa*-*-linux*
5502 OpenBSD/hppa hppa*-*-openbsd*
5503 OpenBSD/m68k m68*-*-openbsd*
5504 OpenBSD/m88k m88*-*-openbsd*
5505 OpenBSD/powerpc powerpc-*-openbsd*
5506 NetBSD/vax vax-*-netbsd*
5507 OpenBSD/vax vax-*-openbsd*
5509 * END-OF-LIFE frame compatibility module
5511 GDB's internal frame infrastructure has been completely rewritten.
5512 The new infrastructure making it possible to support key new features
5513 including DWARF 2 Call Frame Information. To aid in the task of
5514 migrating old configurations to this new infrastructure, a
5515 compatibility module, that allowed old configurations to continue to
5516 work, was also included.
5518 GDB 6.2 will be the last release to include this frame compatibility
5519 module. This change directly impacts the following configurations:
5529 Unless there is activity to revive these configurations, they will be
5530 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
5532 * REMOVED configurations and files
5534 Sun 3, running SunOS 3 m68*-*-sunos3*
5535 Sun 3, running SunOS 4 m68*-*-sunos4*
5536 Sun 2, running SunOS 3 m68000-*-sunos3*
5537 Sun 2, running SunOS 4 m68000-*-sunos4*
5538 Motorola 680x0 running LynxOS m68*-*-lynxos*
5539 AT&T 3b1/Unix pc m68*-att-*
5540 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5541 decstation mips-dec-* mips-little-*
5542 riscos mips-*-riscos* mips-*-sysv*
5543 sonymips mips-sony-*
5544 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5546 *** Changes in GDB 6.1.1:
5548 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
5550 The TUI (Text-mode User Interface) is now built as part of a default
5551 GDB configuration. It is enabled by either selecting the TUI with the
5552 command line option "-i=tui" or by running the separate "gdbtui"
5553 program. For more information on the TUI, see the manual "Debugging
5556 * Pending breakpoint support (also included in GDB 6.1)
5558 Support has been added to allow you to specify breakpoints in shared
5559 libraries that have not yet been loaded. If a breakpoint location
5560 cannot be found, and the "breakpoint pending" option is set to auto,
5561 GDB queries you if you wish to make the breakpoint pending on a future
5562 shared-library load. If and when GDB resolves the breakpoint symbol,
5563 the pending breakpoint is removed as one or more regular breakpoints
5566 Pending breakpoints are very useful for GCJ Java debugging.
5568 * Fixed ISO-C build problems
5570 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
5571 non ISO-C code that stopped them being built using a more strict ISO-C
5572 compiler (e.g., IBM's C compiler).
5574 * Fixed build problem on IRIX 5
5576 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
5577 wasn't able to compile compile on an IRIX 5 system.
5579 * Added execute permission to gdb/gdbserver/configure
5581 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
5582 permission. This bug would cause configure to fail on a number of
5583 systems (Solaris, IRIX). Ref: server/519.
5585 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
5587 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
5588 has been updated to use constant array sizes.
5590 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
5592 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
5593 its generated DWARF Call Frame Info. This encoding was causing GDB to
5594 panic, that panic has been fixed. Ref: gdb/1628.
5596 * Fixed a problem when examining parameters in shared library code.
5598 When examining parameters in optimized shared library code generated
5599 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
5600 not available''. GDB now correctly displays the variable's value.
5602 *** Changes in GDB 6.1:
5604 * Removed --with-mmalloc
5606 Support for the mmalloc memory manager has been removed, as it
5607 conflicted with the internal gdb byte cache.
5609 * Changes in AMD64 configurations
5611 The AMD64 target now includes the %cs and %ss registers. As a result
5612 the AMD64 remote protocol has changed; this affects the floating-point
5613 and SSE registers. If you rely on those registers for your debugging,
5614 you should upgrade gdbserver on the remote side.
5616 * Revised SPARC target
5618 The SPARC target has been completely revised, incorporating the
5619 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
5620 support for LynxOS and SunOS 4 has been dropped. Calling functions
5621 from within GDB on operating systems with a non-executable stack
5622 (Solaris, OpenBSD) now works.
5626 GDB has a new C++ demangler which does a better job on the mangled
5627 names generated by current versions of g++. It also runs faster, so
5628 with this and other changes gdb should now start faster on large C++
5631 * DWARF 2 Location Expressions
5633 GDB support for location expressions has been extended to support function
5634 arguments and frame bases. Older versions of GDB could crash when they
5637 * C++ nested types and namespaces
5639 GDB's support for nested types and namespaces in C++ has been
5640 improved, especially if you use the DWARF 2 debugging format. (This
5641 is the default for recent versions of GCC on most platforms.)
5642 Specifically, if you have a class "Inner" defined within a class or
5643 namespace "Outer", then GDB realizes that the class's name is
5644 "Outer::Inner", not simply "Inner". This should greatly reduce the
5645 frequency of complaints about not finding RTTI symbols. In addition,
5646 if you are stopped at inside of a function defined within a namespace,
5647 GDB modifies its name lookup accordingly.
5649 * New native configurations
5651 NetBSD/amd64 x86_64-*-netbsd*
5652 OpenBSD/amd64 x86_64-*-openbsd*
5653 OpenBSD/alpha alpha*-*-openbsd*
5654 OpenBSD/sparc sparc-*-openbsd*
5655 OpenBSD/sparc64 sparc64-*-openbsd*
5657 * New debugging protocols
5659 M32R with SDI protocol m32r-*-elf*
5661 * "set prompt-escape-char" command deleted.
5663 The command "set prompt-escape-char" has been deleted. This command,
5664 and its very obscure effect on GDB's prompt, was never documented,
5665 tested, nor mentioned in the NEWS file.
5667 * OBSOLETE configurations and files
5669 Configurations that have been declared obsolete in this release have
5670 been commented out. Unless there is activity to revive these
5671 configurations, the next release of GDB will have their sources
5672 permanently REMOVED.
5674 Sun 3, running SunOS 3 m68*-*-sunos3*
5675 Sun 3, running SunOS 4 m68*-*-sunos4*
5676 Sun 2, running SunOS 3 m68000-*-sunos3*
5677 Sun 2, running SunOS 4 m68000-*-sunos4*
5678 Motorola 680x0 running LynxOS m68*-*-lynxos*
5679 AT&T 3b1/Unix pc m68*-att-*
5680 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5681 decstation mips-dec-* mips-little-*
5682 riscos mips-*-riscos* mips-*-sysv*
5683 sonymips mips-sony-*
5684 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5686 * REMOVED configurations and files
5688 SGI Irix-4.x mips-sgi-irix4 or iris4
5689 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5690 Z8000 simulator z8k-zilog-none or z8ksim
5691 Matsushita MN10200 w/simulator mn10200-*-*
5692 H8/500 simulator h8500-hitachi-hms or h8500hms
5693 HP/PA running BSD hppa*-*-bsd*
5694 HP/PA running OSF/1 hppa*-*-osf*
5695 HP/PA Pro target hppa*-*-pro*
5696 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5697 386BSD i[3456]86-*-bsd*
5698 Sequent family i[3456]86-sequent-sysv4*
5699 i[3456]86-sequent-sysv*
5700 i[3456]86-sequent-bsd*
5701 SPARC running LynxOS sparc-*-lynxos*
5702 SPARC running SunOS 4 sparc-*-sunos4*
5703 Tsqware Sparclet sparclet-*-*
5704 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5706 *** Changes in GDB 6.0:
5710 Support for debugging the Objective-C programming language has been
5711 integrated into GDB.
5713 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5715 DWARF 2's Call Frame Information makes available compiler generated
5716 information that more exactly describes the program's run-time stack.
5717 By using this information, GDB is able to provide more robust stack
5720 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5721 have been updated to use a new backtrace mechanism which includes
5722 DWARF 2 CFI support.
5726 GDB's remote protocol has been extended to include support for hosted
5727 file I/O (where the remote target uses GDB's file system). See GDB's
5728 remote protocol documentation for details.
5730 * All targets using the new architecture framework.
5732 All of GDB's targets have been updated to use the new internal
5733 architecture framework. The way is now open for future GDB releases
5734 to include cross-architecture native debugging support (i386 on amd64,
5737 * GNU/Linux's Thread Local Storage (TLS)
5739 GDB now includes support for for the GNU/Linux implementation of
5740 per-thread variables.
5742 * GNU/Linux's Native POSIX Thread Library (NPTL)
5744 GDB's thread code has been updated to work with either the new
5745 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5747 * Separate debug info.
5749 GDB, in conjunction with BINUTILS, now supports a mechanism for
5750 automatically loading debug information from a separate file. Instead
5751 of shipping full debug and non-debug versions of system libraries,
5752 system integrators can now instead ship just the stripped libraries
5753 and optional debug files.
5755 * DWARF 2 Location Expressions
5757 DWARF 2 Location Expressions allow the compiler to more completely
5758 describe the location of variables (even in optimized code) to the
5761 GDB now includes preliminary support for location expressions (support
5762 for DW_OP_piece is still missing).
5766 A number of long standing bugs that caused GDB to die while starting a
5767 Java application have been fixed. GDB's Java support is now
5768 considered "useable".
5770 * GNU/Linux support for fork, vfork, and exec.
5772 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5773 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5776 * GDB supports logging output to a file
5778 There are two new commands, "set logging" and "show logging", which can be
5779 used to capture GDB's output to a file.
5781 * The meaning of "detach" has changed for gdbserver
5783 The "detach" command will now resume the application, as documented. To
5784 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5787 * d10v, m68hc11 `regs' command deprecated
5789 The `info registers' command has been updated so that it displays the
5790 registers using a format identical to the old `regs' command.
5794 A new command, "maint set profile on/off", has been added. This command can
5795 be used to enable or disable profiling while running GDB, to profile a
5796 session or a set of commands. In addition there is a new configure switch,
5797 "--enable-profiling", which will cause GDB to be compiled with profiling
5798 data, for more informative profiling results.
5800 * Default MI syntax changed to "mi2".
5802 The default MI (machine interface) syntax, enabled by the command line
5803 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5804 "mi1", can be enabled by specifying the option "-i=mi1".
5806 Support for the original "mi0" syntax (included in GDB 5.0) has been
5809 Fix for gdb/192: removed extraneous space when displaying frame level.
5810 Fix for gdb/672: update changelist is now output in mi list format.
5811 Fix for gdb/702: a -var-assign that updates the value now shows up
5812 in a subsequent -var-update.
5814 * New native configurations.
5816 FreeBSD/amd64 x86_64-*-freebsd*
5818 * Multi-arched targets.
5820 HP/PA HPUX11 hppa*-*-hpux*
5821 Renesas M32R/D w/simulator m32r-*-elf*
5823 * OBSOLETE configurations and files
5825 Configurations that have been declared obsolete in this release have
5826 been commented out. Unless there is activity to revive these
5827 configurations, the next release of GDB will have their sources
5828 permanently REMOVED.
5830 Z8000 simulator z8k-zilog-none or z8ksim
5831 Matsushita MN10200 w/simulator mn10200-*-*
5832 H8/500 simulator h8500-hitachi-hms or h8500hms
5833 HP/PA running BSD hppa*-*-bsd*
5834 HP/PA running OSF/1 hppa*-*-osf*
5835 HP/PA Pro target hppa*-*-pro*
5836 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5837 Sequent family i[3456]86-sequent-sysv4*
5838 i[3456]86-sequent-sysv*
5839 i[3456]86-sequent-bsd*
5840 Tsqware Sparclet sparclet-*-*
5841 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5843 * REMOVED configurations and files
5846 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5847 IBM AIX PS/2 i[3456]86-*-aix
5848 i386 running Mach 3.0 i[3456]86-*-mach3*
5849 i386 running Mach i[3456]86-*-mach*
5850 i386 running OSF/1 i[3456]86-*osf1mk*
5851 HP/Apollo 68k Family m68*-apollo*-sysv*,
5853 m68*-hp-bsd*, m68*-hp-hpux*
5854 Argonaut Risc Chip (ARC) arc-*-*
5855 Mitsubishi D30V d30v-*-*
5856 Fujitsu FR30 fr30-*-elf*
5857 OS/9000 i[34]86-*-os9k
5858 I960 with MON960 i960-*-coff
5860 * MIPS $fp behavior changed
5862 The convenience variable $fp, for the MIPS, now consistently returns
5863 the address of the current frame's base. Previously, depending on the
5864 context, $fp could refer to either $sp or the current frame's base
5865 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5866 The GNU Source-Level Debugger''.
5868 *** Changes in GDB 5.3:
5870 * GNU/Linux shared library multi-threaded performance improved.
5872 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5873 `/proc', in preference to `ptrace' for memory reads. This may result
5874 in an improvement in the start-up time of multi-threaded, shared
5875 library applications when run under GDB. One GDB user writes: ``loads
5876 shared libs like mad''.
5878 * ``gdbserver'' now supports multi-threaded applications on some targets
5880 Support for debugging multi-threaded applications which use
5881 the GNU/Linux LinuxThreads package has been added for
5882 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5883 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5885 * GDB now supports C/C++ preprocessor macros.
5887 GDB now expands preprocessor macro invocations in C/C++ expressions,
5888 and provides various commands for showing macro definitions and how
5891 The new command `macro expand EXPRESSION' expands any macro
5892 invocations in expression, and shows the result.
5894 The new command `show macro MACRO-NAME' shows the definition of the
5895 macro named MACRO-NAME, and where it was defined.
5897 Most compilers don't include information about macros in the debugging
5898 information by default. In GCC 3.1, for example, you need to compile
5899 your program with the options `-gdwarf-2 -g3'. If the macro
5900 information is present in the executable, GDB will read it.
5902 * Multi-arched targets.
5904 DEC Alpha (partial) alpha*-*-*
5905 DEC VAX (partial) vax-*-*
5907 National Semiconductor NS32000 (partial) ns32k-*-*
5908 Motorola 68000 (partial) m68k-*-*
5909 Motorola MCORE mcore-*-*
5913 Fujitsu FRV architecture added by Red Hat frv*-*-*
5916 * New native configurations
5918 Alpha NetBSD alpha*-*-netbsd*
5919 SH NetBSD sh*-*-netbsdelf*
5920 MIPS NetBSD mips*-*-netbsd*
5921 UltraSPARC NetBSD sparc64-*-netbsd*
5923 * OBSOLETE configurations and files
5925 Configurations that have been declared obsolete in this release have
5926 been commented out. Unless there is activity to revive these
5927 configurations, the next release of GDB will have their sources
5928 permanently REMOVED.
5930 Mitsubishi D30V d30v-*-*
5931 OS/9000 i[34]86-*-os9k
5932 IBM AIX PS/2 i[3456]86-*-aix
5933 Fujitsu FR30 fr30-*-elf*
5934 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5935 Argonaut Risc Chip (ARC) arc-*-*
5936 i386 running Mach 3.0 i[3456]86-*-mach3*
5937 i386 running Mach i[3456]86-*-mach*
5938 i386 running OSF/1 i[3456]86-*osf1mk*
5939 HP/Apollo 68k Family m68*-apollo*-sysv*,
5941 m68*-hp-bsd*, m68*-hp-hpux*
5942 I960 with MON960 i960-*-coff
5944 * OBSOLETE languages
5946 CHILL, a Pascal like language used by telecommunications companies.
5948 * REMOVED configurations and files
5950 AMD 29k family via UDI a29k-amd-udi, udi29k
5951 A29K VxWorks a29k-*-vxworks
5952 AMD 29000 embedded, using EBMON a29k-none-none
5953 AMD 29000 embedded with COFF a29k-none-coff
5954 AMD 29000 embedded with a.out a29k-none-aout
5956 testsuite/gdb.hp/gdb.threads-hp/ directory
5958 * New command "set max-user-call-depth <nnn>"
5960 This command allows the user to limit the call depth of user-defined
5961 commands. The default is 1024.
5963 * Changes in FreeBSD/i386 native debugging.
5965 Support for the "generate-core-file" has been added.
5967 * New commands "dump", "append", and "restore".
5969 These commands allow data to be copied from target memory
5970 to a bfd-format or binary file (dump and append), and back
5971 from a file into memory (restore).
5973 * Improved "next/step" support on multi-processor Alpha Tru64.
5975 The previous single-step mechanism could cause unpredictable problems,
5976 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5977 of a software single-step mechanism prevents this.
5979 *** Changes in GDB 5.2.1:
5987 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5988 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5989 Fix, by Joel Brobecker imported from mainline.
5991 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5992 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5993 Fix, by Fred Fish, imported from mainline.
5995 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5996 Surprisingly enough, it works now.
5997 By Michal Ludvig, imported from mainline.
5999 i386 hardware watchpoint support:
6000 avoid misses on second run for some targets.
6001 By Pierre Muller, imported from mainline.
6003 *** Changes in GDB 5.2:
6005 * New command "set trust-readonly-sections on[off]".
6007 This command is a hint that tells gdb that read-only sections
6008 really are read-only (ie. that their contents will not change).
6009 In this mode, gdb will go to the object file rather than the
6010 target to read memory from read-only sections (such as ".text").
6011 This can be a significant performance improvement on some
6012 (notably embedded) targets.
6014 * New command "generate-core-file" (or "gcore").
6016 This new gdb command allows the user to drop a core file of the child
6017 process state at any time. So far it's been implemented only for
6018 GNU/Linux and Solaris, but should be relatively easily ported to other
6019 hosts. Argument is core file name (defaults to core.<pid>).
6021 * New command line option
6023 GDB now accepts --pid or -p followed by a process id.
6025 * Change in command line behavior -- corefiles vs. process ids.
6027 There is a subtle behavior in the way in which GDB handles
6028 command line arguments. The first non-flag argument is always
6029 a program to debug, but the second non-flag argument may either
6030 be a corefile or a process id. Previously, GDB would attempt to
6031 open the second argument as a corefile, and if that failed, would
6032 issue a superfluous error message and then attempt to attach it as
6033 a process. Now, if the second argument begins with a non-digit,
6034 it will be treated as a corefile. If it begins with a digit,
6035 GDB will attempt to attach it as a process, and if no such process
6036 is found, will then attempt to open it as a corefile.
6038 * Changes in ARM configurations.
6040 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
6041 configuration is fully multi-arch.
6043 * New native configurations
6045 ARM NetBSD arm*-*-netbsd*
6046 x86 OpenBSD i[3456]86-*-openbsd*
6047 AMD x86-64 running GNU/Linux x86_64-*-linux-*
6048 Sparc64 running FreeBSD sparc64-*-freebsd*
6052 Sanyo XStormy16 xstormy16-elf
6054 * OBSOLETE configurations and files
6056 Configurations that have been declared obsolete in this release have
6057 been commented out. Unless there is activity to revive these
6058 configurations, the next release of GDB will have their sources
6059 permanently REMOVED.
6061 AMD 29k family via UDI a29k-amd-udi, udi29k
6062 A29K VxWorks a29k-*-vxworks
6063 AMD 29000 embedded, using EBMON a29k-none-none
6064 AMD 29000 embedded with COFF a29k-none-coff
6065 AMD 29000 embedded with a.out a29k-none-aout
6067 testsuite/gdb.hp/gdb.threads-hp/ directory
6069 * REMOVED configurations and files
6071 TI TMS320C80 tic80-*-*
6073 PowerPC Solaris powerpcle-*-solaris*
6074 PowerPC Windows NT powerpcle-*-cygwin32
6075 PowerPC Netware powerpc-*-netware*
6076 Harris/CXUX m88k m88*-harris-cxux*
6077 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
6078 ns32k-utek-sysv* ns32k-utek-*
6079 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
6080 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
6081 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
6082 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
6083 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
6085 * Changes to command line processing
6087 The new `--args' feature can be used to specify command-line arguments
6088 for the inferior from gdb's command line.
6090 * Changes to key bindings
6092 There is a new `operate-and-get-next' function bound to `C-o'.
6094 *** Changes in GDB 5.1.1
6096 Fix compile problem on DJGPP.
6098 Fix a problem with floating-point registers on the i386 being
6101 Fix to stop GDB crashing on .debug_str debug info.
6103 Numerous documentation fixes.
6105 Numerous testsuite fixes.
6107 *** Changes in GDB 5.1:
6109 * New native configurations
6111 Alpha FreeBSD alpha*-*-freebsd*
6112 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
6113 MIPS GNU/Linux mips*-*-linux*
6114 MIPS SGI Irix 6.x mips*-sgi-irix6*
6115 ia64 AIX ia64-*-aix*
6116 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
6120 Motorola 68HC11 and 68HC12 m68hc11-elf
6122 UltraSparc running GNU/Linux sparc64-*-linux*
6124 * OBSOLETE configurations and files
6126 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
6127 Harris/CXUX m88k m88*-harris-cxux*
6128 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
6129 ns32k-utek-sysv* ns32k-utek-*
6130 TI TMS320C80 tic80-*-*
6132 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
6133 PowerPC Solaris powerpcle-*-solaris*
6134 PowerPC Windows NT powerpcle-*-cygwin32
6135 PowerPC Netware powerpc-*-netware*
6136 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
6137 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
6138 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
6139 Apple Macintosh (MPW) host N/A
6141 stuff.c (Program to stuff files into a specially prepared space in kdb)
6142 kdb-start.c (Main loop for the standalone kernel debugger)
6144 Configurations that have been declared obsolete in this release have
6145 been commented out. Unless there is activity to revive these
6146 configurations, the next release of GDB will have their sources
6147 permanently REMOVED.
6149 * REMOVED configurations and files
6151 Altos 3068 m68*-altos-*
6152 Convex c1-*-*, c2-*-*
6154 ARM RISCix arm-*-* (as host)
6158 * GDB has been converted to ISO C.
6160 GDB's source code has been converted to ISO C. In particular, the
6161 sources are fully protoized, and rely on standard headers being
6166 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
6168 * The MI enabled by default.
6170 The new machine oriented interface (MI) introduced in GDB 5.0 has been
6171 revised and enabled by default. Packages which use GDB as a debugging
6172 engine behind a UI or another front end are encouraged to switch to
6173 using the GDB/MI interface, instead of the old annotations interface
6174 which is now deprecated.
6176 * Support for debugging Pascal programs.
6178 GDB now includes support for debugging Pascal programs. The following
6179 main features are supported:
6181 - Pascal-specific data types such as sets;
6183 - automatic recognition of Pascal sources based on file-name
6186 - Pascal-style display of data types, variables, and functions;
6188 - a Pascal expression parser.
6190 However, some important features are not yet supported.
6192 - Pascal string operations are not supported at all;
6194 - there are some problems with boolean types;
6196 - Pascal type hexadecimal constants are not supported
6197 because they conflict with the internal variables format;
6199 - support for Pascal objects and classes is not full yet;
6201 - unlike Pascal, GDB is case-sensitive for symbol names.
6203 * Changes in completion.
6205 Commands such as `shell', `run' and `set args', which pass arguments
6206 to inferior programs, now complete on file names, similar to what
6207 users expect at the shell prompt.
6209 Commands which accept locations, such as `disassemble', `print',
6210 `breakpoint', `until', etc. now complete on filenames as well as
6211 program symbols. Thus, if you type "break foob TAB", and the source
6212 files linked into the programs include `foobar.c', that file name will
6213 be one of the candidates for completion. However, file names are not
6214 considered for completion after you typed a colon that delimits a file
6215 name from a name of a function in that file, as in "break foo.c:bar".
6217 `set demangle-style' completes on available demangling styles.
6219 * New platform-independent commands:
6221 It is now possible to define a post-hook for a command as well as a
6222 hook that runs before the command. For more details, see the
6223 documentation of `hookpost' in the GDB manual.
6225 * Changes in GNU/Linux native debugging.
6227 Support for debugging multi-threaded programs has been completely
6228 revised for all platforms except m68k and sparc. You can now debug as
6229 many threads as your system allows you to have.
6231 Attach/detach is supported for multi-threaded programs.
6233 Support for SSE registers was added for x86. This doesn't work for
6234 multi-threaded programs though.
6236 * Changes in MIPS configurations.
6238 Multi-arch support is enabled for all MIPS configurations.
6240 GDB can now be built as native debugger on SGI Irix 6.x systems for
6241 debugging n32 executables. (Debugging 64-bit executables is not yet
6244 * Unified support for hardware watchpoints in all x86 configurations.
6246 Most (if not all) native x86 configurations support hardware-assisted
6247 breakpoints and watchpoints in a unified manner. This support
6248 implements debug register sharing between watchpoints, which allows to
6249 put a virtually infinite number of watchpoints on the same address,
6250 and also supports watching regions up to 16 bytes with several debug
6253 The new maintenance command `maintenance show-debug-regs' toggles
6254 debugging print-outs in functions that insert, remove, and test
6255 watchpoints and hardware breakpoints.
6257 * Changes in the DJGPP native configuration.
6259 New command ``info dos sysinfo'' displays assorted information about
6260 the CPU, OS, memory, and DPMI server.
6262 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
6263 display information about segment descriptors stored in GDT, LDT, and
6266 New commands ``info dos pde'' and ``info dos pte'' display entries
6267 from Page Directory and Page Tables (for now works with CWSDPMI only).
6268 New command ``info dos address-pte'' displays the Page Table entry for
6269 a given linear address.
6271 GDB can now pass command lines longer than 126 characters to the
6272 program being debugged (requires an update to the libdbg.a library
6273 which is part of the DJGPP development kit).
6275 DWARF2 debug info is now supported.
6277 It is now possible to `step' and `next' through calls to `longjmp'.
6279 * Changes in documentation.
6281 All GDB documentation was converted to GFDL, the GNU Free
6282 Documentation License.
6284 Tracepoints-related commands are now fully documented in the GDB
6287 TUI, the Text-mode User Interface, is now documented in the manual.
6289 Tracepoints-related commands are now fully documented in the GDB
6292 The "GDB Internals" manual now has an index. It also includes
6293 documentation of `ui_out' functions, GDB coding standards, x86
6294 hardware watchpoints, and memory region attributes.
6296 * GDB's version number moved to ``version.in''
6298 The Makefile variable VERSION has been replaced by the file
6299 ``version.in''. People creating GDB distributions should update the
6300 contents of this file.
6304 GUD support is now a standard part of the EMACS distribution.
6306 *** Changes in GDB 5.0:
6308 * Improved support for debugging FP programs on x86 targets
6310 Unified and much-improved support for debugging floating-point
6311 programs on all x86 targets. In particular, ``info float'' now
6312 displays the FP registers in the same format on all x86 targets, with
6313 greater level of detail.
6315 * Improvements and bugfixes in hardware-assisted watchpoints
6317 It is now possible to watch array elements, struct members, and
6318 bitfields with hardware-assisted watchpoints. Data-read watchpoints
6319 on x86 targets no longer erroneously trigger when the address is
6322 * Improvements in the native DJGPP version of GDB
6324 The distribution now includes all the scripts and auxiliary files
6325 necessary to build the native DJGPP version on MS-DOS/MS-Windows
6326 machines ``out of the box''.
6328 The DJGPP version can now debug programs that use signals. It is
6329 possible to catch signals that happened in the debuggee, deliver
6330 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
6331 would kill the program being debugged.) Programs that hook hardware
6332 interrupts (keyboard, timer, etc.) can also be debugged.
6334 It is now possible to debug DJGPP programs that redirect their
6335 standard handles or switch them to raw (as opposed to cooked) mode, or
6336 even close them. The command ``run < foo > bar'' works as expected,
6337 and ``info terminal'' reports useful information about the debuggee's
6338 terminal, including raw/cooked mode, redirection, etc.
6340 The DJGPP version now uses termios functions for console I/O, which
6341 enables debugging graphics programs. Interrupting GDB with Ctrl-C
6344 DOS-style file names with drive letters are now fully supported by
6347 It is now possible to debug DJGPP programs that switch their working
6348 directory. It is also possible to rerun the debuggee any number of
6349 times without restarting GDB; thus, you can use the same setup,
6350 breakpoints, etc. for many debugging sessions.
6352 * New native configurations
6354 ARM GNU/Linux arm*-*-linux*
6355 PowerPC GNU/Linux powerpc-*-linux*
6359 Motorola MCore mcore-*-*
6360 x86 VxWorks i[3456]86-*-vxworks*
6361 PowerPC VxWorks powerpc-*-vxworks*
6362 TI TMS320C80 tic80-*-*
6364 * OBSOLETE configurations
6366 Altos 3068 m68*-altos-*
6367 Convex c1-*-*, c2-*-*
6369 ARM RISCix arm-*-* (as host)
6372 Configurations that have been declared obsolete will be commented out,
6373 but the code will be left in place. If there is no activity to revive
6374 these configurations before the next release of GDB, the sources will
6375 be permanently REMOVED.
6377 * Gould support removed
6379 Support for the Gould PowerNode and NP1 has been removed.
6381 * New features for SVR4
6383 On SVR4 native platforms (such as Solaris), if you attach to a process
6384 without first loading a symbol file, GDB will now attempt to locate and
6385 load symbols from the running process's executable file.
6387 * Many C++ enhancements
6389 C++ support has been greatly improved. Overload resolution now works properly
6390 in almost all cases. RTTI support is on the way.
6392 * Remote targets can connect to a sub-program
6394 A popen(3) style serial-device has been added. This device starts a
6395 sub-process (such as a stand-alone simulator) and then communicates
6396 with that. The sub-program to run is specified using the syntax
6397 ``|<program> <args>'' vis:
6399 (gdb) set remotedebug 1
6400 (gdb) target extended-remote |mn10300-elf-sim program-args
6402 * MIPS 64 remote protocol
6404 A long standing bug in the mips64 remote protocol where by GDB
6405 expected certain 32 bit registers (ex SR) to be transfered as 32
6406 instead of 64 bits has been fixed.
6408 The command ``set remote-mips64-transfers-32bit-regs on'' has been
6409 added to provide backward compatibility with older versions of GDB.
6411 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
6413 The command ``set remotebinarydownload'' command has been replaced by
6414 ``set remote X-packet''. Other commands in ``set remote'' family
6415 include ``set remote P-packet''.
6417 * Breakpoint commands accept ranges.
6419 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
6420 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
6421 ``tracepoint passcount'' also accepts a range of tracepoints.
6423 * ``apropos'' command added.
6425 The ``apropos'' command searches through command names and
6426 documentation strings, printing out matches, making it much easier to
6427 try to find a command that does what you are looking for.
6431 A new machine oriented interface (MI) has been added to GDB. This
6432 interface is designed for debug environments running GDB as a separate
6433 process. This is part of the long term libGDB project. See the
6434 "GDB/MI" chapter of the GDB manual for further information. It can be
6435 enabled by configuring with:
6437 .../configure --enable-gdbmi
6439 *** Changes in GDB-4.18:
6441 * New native configurations
6443 HP-UX 10.20 hppa*-*-hpux10.20
6444 HP-UX 11.x hppa*-*-hpux11.0*
6445 M68K GNU/Linux m68*-*-linux*
6449 Fujitsu FR30 fr30-*-elf*
6450 Intel StrongARM strongarm-*-*
6451 Mitsubishi D30V d30v-*-*
6453 * OBSOLETE configurations
6455 Gould PowerNode, NP1 np1-*-*, pn-*-*
6457 Configurations that have been declared obsolete will be commented out,
6458 but the code will be left in place. If there is no activity to revive
6459 these configurations before the next release of GDB, the sources will
6460 be permanently REMOVED.
6464 As a compatibility experiment, GDB's source files buildsym.h and
6465 buildsym.c have been converted to pure standard C, no longer
6466 containing any K&R compatibility code. We believe that all systems in
6467 use today either come with a standard C compiler, or have a GCC port
6468 available. If this is not true, please report the affected
6469 configuration to bug-gdb@gnu.org immediately. See the README file for
6470 information about getting a standard C compiler if you don't have one
6475 GDB now uses readline 2.2.
6477 * set extension-language
6479 You can now control the mapping between filename extensions and source
6480 languages by using the `set extension-language' command. For instance,
6481 you can ask GDB to treat .c files as C++ by saying
6482 set extension-language .c c++
6483 The command `info extensions' lists all of the recognized extensions
6484 and their associated languages.
6486 * Setting processor type for PowerPC and RS/6000
6488 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
6489 you can use the `set processor' command to specify what variant of the
6490 PowerPC family you are debugging. The command
6494 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
6495 following PowerPC and RS6000 variants:
6497 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
6498 rs6000 IBM RS6000 ("POWER") architecture, user-level view
6500 403GC IBM PowerPC 403GC
6501 505 Motorola PowerPC 505
6502 860 Motorola PowerPC 860 or 850
6503 601 Motorola PowerPC 601
6504 602 Motorola PowerPC 602
6505 603 Motorola/IBM PowerPC 603 or 603e
6506 604 Motorola PowerPC 604 or 604e
6507 750 Motorola/IBM PowerPC 750 or 750
6509 At the moment, this command just tells GDB what to name the
6510 special-purpose processor registers. Since almost all the affected
6511 registers are inaccessible to user-level programs, this command is
6512 only useful for remote debugging in its present form.
6516 Thanks to a major code donation from Hewlett-Packard, GDB now has much
6517 more extensive support for HP-UX. Added features include shared
6518 library support, kernel threads and hardware watchpoints for 11.00,
6519 support for HP's ANSI C and C++ compilers, and a compatibility mode
6520 for xdb and dbx commands.
6524 HP's donation includes the new concept of catchpoints, which is a
6525 generalization of the old catch command. On HP-UX, it is now possible
6526 to catch exec, fork, and vfork, as well as library loading.
6528 This means that the existing catch command has changed; its first
6529 argument now specifies the type of catch to be set up. See the
6530 output of "help catch" for a list of catchpoint types.
6532 * Debugging across forks
6534 On HP-UX, you can choose which process to debug when a fork() happens
6539 HP has donated a curses-based terminal user interface (TUI). To get
6540 it, build with --enable-tui. Although this can be enabled for any
6541 configuration, at present it only works for native HP debugging.
6543 * GDB remote protocol additions
6545 A new protocol packet 'X' that writes binary data is now available.
6546 Default behavior is to try 'X', then drop back to 'M' if the stub
6547 fails to respond. The settable variable `remotebinarydownload'
6548 allows explicit control over the use of 'X'.
6550 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
6551 full 64-bit address. The command
6553 set remoteaddresssize 32
6555 can be used to revert to the old behaviour. For existing remote stubs
6556 the change should not be noticed, as the additional address information
6559 In order to assist in debugging stubs, you may use the maintenance
6560 command `packet' to send any text string to the stub. For instance,
6562 maint packet heythere
6564 sends the packet "$heythere#<checksum>". Note that it is very easy to
6565 disrupt a debugging session by sending the wrong packet at the wrong
6568 The compare-sections command allows you to compare section data on the
6569 target to what is in the executable file without uploading or
6570 downloading, by comparing CRC checksums.
6572 * Tracing can collect general expressions
6574 You may now collect general expressions at tracepoints. This requires
6575 further additions to the target-side stub; see tracepoint.c and
6576 doc/agentexpr.texi for further details.
6578 * mask-address variable for Mips
6580 For Mips targets, you may control the zeroing of the upper 32 bits of
6581 a 64-bit address by entering `set mask-address on'. This is mainly
6582 of interest to users of embedded R4xxx and R5xxx processors.
6584 * Higher serial baud rates
6586 GDB's serial code now allows you to specify baud rates 57600, 115200,
6587 230400, and 460800 baud. (Note that your host system may not be able
6588 to achieve all of these rates.)
6592 The i960 configuration now includes an initial implementation of a
6593 builtin simulator, contributed by Jim Wilson.
6596 *** Changes in GDB-4.17:
6598 * New native configurations
6600 Alpha GNU/Linux alpha*-*-linux*
6601 Unixware 2.x i[3456]86-unixware2*
6602 Irix 6.x mips*-sgi-irix6*
6603 PowerPC GNU/Linux powerpc-*-linux*
6604 PowerPC Solaris powerpcle-*-solaris*
6605 Sparc GNU/Linux sparc-*-linux*
6606 Motorola sysV68 R3V7.1 m68k-motorola-sysv
6610 Argonaut Risc Chip (ARC) arc-*-*
6611 Hitachi H8/300S h8300*-*-*
6612 Matsushita MN10200 w/simulator mn10200-*-*
6613 Matsushita MN10300 w/simulator mn10300-*-*
6614 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
6615 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
6616 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
6617 Mitsubishi D10V w/simulator d10v-*-*
6618 Mitsubishi M32R/D w/simulator m32r-*-elf*
6619 Tsqware Sparclet sparclet-*-*
6620 NEC V850 w/simulator v850-*-*
6622 * New debugging protocols
6624 ARM with RDI protocol arm*-*-*
6625 M68K with dBUG monitor m68*-*-{aout,coff,elf}
6626 DDB and LSI variants of PMON protocol mips*-*-*
6627 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
6628 PowerPC with SDS protocol powerpc{,le}-*-eabi
6629 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6633 All configurations can now understand and use the DWARF 2 debugging
6634 format. The choice is automatic, if the symbol file contains DWARF 2
6639 GDB now includes basic Java language support. This support is
6640 only useful with Java compilers that produce native machine code.
6642 * solib-absolute-prefix and solib-search-path
6644 For SunOS and SVR4 shared libraries, you may now set the prefix for
6645 loading absolute shared library symbol files, and the search path for
6646 locating non-absolute shared library symbol files.
6648 * Live range splitting
6650 GDB can now effectively debug code for which GCC has performed live
6651 range splitting as part of its optimization. See gdb/doc/LRS for
6652 more details on the expected format of the stabs information.
6656 GDB's support for the GNU Hurd, including thread debugging, has been
6657 updated to work with current versions of the Hurd.
6661 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6662 instruction set. ARM GDB automatically detects when Thumb
6663 instructions are in use, and adjusts disassembly and backtracing
6668 GDB's MIPS target configurations now handle the MIP16 16-bit
6673 GDB now includes support for overlays; if an executable has been
6674 linked such that multiple sections are based at the same address, GDB
6675 will decide which section to use for symbolic info. You can choose to
6676 control the decision manually, using overlay commands, or implement
6677 additional target-side support and use "overlay load-target" to bring
6678 in the overlay mapping. Do "help overlay" for more detail.
6682 The command "info symbol <address>" displays information about
6683 the symbol at the specified address.
6687 The standard remote protocol now includes an extension that allows
6688 asynchronous collection and display of trace data. This requires
6689 extensive support in the target-side debugging stub. Tracing mode
6690 includes a new interaction mode in GDB and new commands: see the
6691 file tracepoint.c for more details.
6695 Configurations for embedded MIPS now include a simulator contributed
6696 by Cygnus Solutions. The simulator supports the instruction sets
6697 of most MIPS variants.
6701 Sparc configurations may now include the ERC32 simulator contributed
6702 by the European Space Agency. The simulator is not built into
6703 Sparc targets by default; configure with --enable-sim to include it.
6707 For target configurations that may include multiple variants of a
6708 basic architecture (such as MIPS and SH), you may now set the
6709 architecture explicitly. "set arch" sets, "info arch" lists
6710 the possible architectures.
6712 *** Changes in GDB-4.16:
6714 * New native configurations
6716 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6717 M68K NetBSD m68k-*-netbsd*
6718 PowerPC AIX 4.x powerpc-*-aix*
6719 PowerPC MacOS powerpc-*-macos*
6720 PowerPC Windows NT powerpcle-*-cygwin32
6721 RS/6000 AIX 4.x rs6000-*-aix4*
6725 ARM with RDP protocol arm-*-*
6726 I960 with MON960 i960-*-coff
6727 MIPS VxWorks mips*-*-vxworks*
6728 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6729 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6731 Matra Sparclet sparclet-*-*
6735 The powerpc-eabi configuration now includes the PSIM simulator,
6736 contributed by Andrew Cagney, with assistance from Mike Meissner.
6737 PSIM is a very elaborate model of the PowerPC, including not only
6738 basic instruction set execution, but also details of execution unit
6739 performance and I/O hardware. See sim/ppc/README for more details.
6743 GDB now works with Solaris 2.5.
6745 * Windows 95/NT native
6747 GDB will now work as a native debugger on Windows 95 and Windows NT.
6748 To build it from source, you must use the "gnu-win32" environment,
6749 which uses a DLL to emulate enough of Unix to run the GNU tools.
6750 Further information, binaries, and sources are available at
6751 ftp.cygnus.com, under pub/gnu-win32.
6753 * dont-repeat command
6755 If a user-defined command includes the command `dont-repeat', then the
6756 command will not be repeated if the user just types return. This is
6757 useful if the command is time-consuming to run, so that accidental
6758 extra keystrokes don't run the same command many times.
6760 * Send break instead of ^C
6762 The standard remote protocol now includes an option to send a break
6763 rather than a ^C to the target in order to interrupt it. By default,
6764 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6766 * Remote protocol timeout
6768 The standard remote protocol includes a new variable `remotetimeout'
6769 that allows you to set the number of seconds before GDB gives up trying
6770 to read from the target. The default value is 2.
6772 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6774 By default GDB will automatically keep track of objects as they are
6775 loaded and unloaded by the dynamic linker. By using the command `set
6776 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6777 when shared library events occur, thus allowing you to set breakpoints
6778 in shared libraries which are explicitly loaded by the inferior.
6780 Note this feature does not work on hpux8. On hpux9 you must link
6781 /usr/lib/end.o into your program. This feature should work
6782 automatically on hpux10.
6784 * Irix 5.x hardware watchpoint support
6786 Irix 5 configurations now support the use of hardware watchpoints.
6788 * Mips protocol "SYN garbage limit"
6790 When debugging a Mips target using the `target mips' protocol, you
6791 may set the number of characters that GDB will ignore by setting
6792 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6793 every character. The default value is 1050.
6795 * Recording and replaying remote debug sessions
6797 If you set `remotelogfile' to the name of a file, gdb will write to it
6798 a recording of a remote debug session. This recording may then be
6799 replayed back to gdb using "gdbreplay". See gdbserver/README for
6800 details. This is useful when you have a problem with GDB while doing
6801 remote debugging; you can make a recording of the session and send it
6802 to someone else, who can then recreate the problem.
6804 * Speedups for remote debugging
6806 GDB includes speedups for downloading and stepping MIPS systems using
6807 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6808 and more efficient S-record downloading.
6810 * Memory use reductions and statistics collection
6812 GDB now uses less memory and reports statistics about memory usage.
6813 Try the `maint print statistics' command, for example.
6815 *** Changes in GDB-4.15:
6817 * Psymtabs for XCOFF
6819 The symbol reader for AIX GDB now uses partial symbol tables. This
6820 can greatly improve startup time, especially for large executables.
6822 * Remote targets use caching
6824 Remote targets now use a data cache to speed up communication with the
6825 remote side. The data cache could lead to incorrect results because
6826 it doesn't know about volatile variables, thus making it impossible to
6827 debug targets which use memory mapped I/O devices. `set remotecache
6828 off' turns the data cache off.
6830 * Remote targets may have threads
6832 The standard remote protocol now includes support for multiple threads
6833 in the target system, using new protocol commands 'H' and 'T'. See
6834 gdb/remote.c for details.
6838 If GDB is configured with `--enable-netrom', then it will include
6839 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6840 acts as though it is a bank of ROM on the target board, but you can
6841 write into it over the network. GDB's support consists only of
6842 support for fast loading into the emulated ROM; to debug, you must use
6843 another protocol, such as standard remote protocol. The usual
6844 sequence is something like
6846 target nrom <netrom-hostname>
6848 target remote <netrom-hostname>:1235
6852 GDB now includes support for the Apple Macintosh, as a host only. It
6853 may be run as either an MPW tool or as a standalone application, and
6854 it can debug through the serial port. All the usual GDB commands are
6855 available, but to the target command, you must supply "serial" as the
6856 device type instead of "/dev/ttyXX". See mpw-README in the main
6857 directory for more information on how to build. The MPW configuration
6858 scripts */mpw-config.in support only a few targets, and only the
6859 mips-idt-ecoff target has been tested.
6863 GDB configuration now uses autoconf. This is not user-visible,
6864 but does simplify configuration and building.
6868 GDB now supports hpux10.
6870 *** Changes in GDB-4.14:
6872 * New native configurations
6874 x86 FreeBSD i[345]86-*-freebsd
6875 x86 NetBSD i[345]86-*-netbsd
6876 NS32k NetBSD ns32k-*-netbsd
6877 Sparc NetBSD sparc-*-netbsd
6881 A29K VxWorks a29k-*-vxworks
6882 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6883 CPU32 EST-300 emulator m68*-*-est*
6884 PowerPC ELF powerpc-*-elf
6887 * Alpha OSF/1 support for procfs
6889 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6890 possible to attach to running processes. As the mounting of the /proc
6891 filesystem is optional on the Alpha, GDB automatically determines
6892 the availability of /proc during startup. This can lead to problems
6893 if /proc is unmounted after GDB has been started.
6895 * Arguments to user-defined commands
6897 User commands may accept up to 10 arguments separated by whitespace.
6898 Arguments are accessed within the user command via $arg0..$arg9. A
6901 print $arg0 + $arg1 + $arg2
6903 To execute the command use:
6906 Defines the command "adder" which prints the sum of its three arguments.
6907 Note the arguments are text substitutions, so they may reference variables,
6908 use complex expressions, or even perform inferior function calls.
6910 * New `if' and `while' commands
6912 This makes it possible to write more sophisticated user-defined
6913 commands. Both commands take a single argument, which is the
6914 expression to evaluate, and must be followed by the commands to
6915 execute, one per line, if the expression is nonzero, the list being
6916 terminated by the word `end'. The `if' command list may include an
6917 `else' word, which causes the following commands to be executed only
6918 if the expression is zero.
6920 * Fortran source language mode
6922 GDB now includes partial support for Fortran 77. It will recognize
6923 Fortran programs and can evaluate a subset of Fortran expressions, but
6924 variables and functions may not be handled correctly. GDB will work
6925 with G77, but does not yet know much about symbols emitted by other
6928 * Better HPUX support
6930 Most debugging facilities now work on dynamic executables for HPPAs
6931 running hpux9 or later. You can attach to running dynamically linked
6932 processes, but by default the dynamic libraries will be read-only, so
6933 for instance you won't be able to put breakpoints in them. To change
6934 that behavior do the following before running the program:
6940 This will cause the libraries to be mapped private and read-write.
6941 To revert to the normal behavior, do this:
6947 You cannot set breakpoints or examine data in the library until after
6948 the library is loaded if the function/data symbols do not have
6951 GDB can now also read debug symbols produced by the HP C compiler on
6952 HPPAs (sorry, no C++, Fortran or 68k support).
6954 * Target byte order now dynamically selectable
6956 You can choose which byte order to use with a target system, via the
6957 commands "set endian big" and "set endian little", and you can see the
6958 current setting by using "show endian". You can also give the command
6959 "set endian auto", in which case GDB will use the byte order
6960 associated with the executable. Currently, only embedded MIPS
6961 configurations support dynamic selection of target byte order.
6963 * New DOS host serial code
6965 This version uses DPMI interrupts to handle buffered I/O, so you
6966 no longer need to run asynctsr when debugging boards connected to
6969 *** Changes in GDB-4.13:
6971 * New "complete" command
6973 This lists all the possible completions for the rest of the line, if it
6974 were to be given as a command itself. This is intended for use by emacs.
6976 * Trailing space optional in prompt
6978 "set prompt" no longer adds a space for you after the prompt you set. This
6979 allows you to set a prompt which ends in a space or one that does not.
6981 * Breakpoint hit counts
6983 "info break" now displays a count of the number of times the breakpoint
6984 has been hit. This is especially useful in conjunction with "ignore"; you
6985 can ignore a large number of breakpoint hits, look at the breakpoint info
6986 to see how many times the breakpoint was hit, then run again, ignoring one
6987 less than that number, and this will get you quickly to the last hit of
6990 * Ability to stop printing at NULL character
6992 "set print null-stop" will cause GDB to stop printing the characters of
6993 an array when the first NULL is encountered. This is useful when large
6994 arrays actually contain only short strings.
6996 * Shared library breakpoints
6998 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6999 breakpoints in shared libraries before the executable is run.
7001 * Hardware watchpoints
7003 There is a new hardware breakpoint for the watch command for sparclite
7004 targets. See gdb/sparclite/hw_breakpoint.note.
7006 Hardware watchpoints are also now supported under GNU/Linux.
7010 Annotations have been added. These are for use with graphical interfaces,
7011 and are still experimental. Currently only gdba.el uses these.
7013 * Improved Irix 5 support
7015 GDB now works properly with Irix 5.2.
7017 * Improved HPPA support
7019 GDB now works properly with the latest GCC and GAS.
7021 * New native configurations
7023 Sequent PTX4 i[34]86-sequent-ptx4
7024 HPPA running OSF/1 hppa*-*-osf*
7025 Atari TT running SVR4 m68*-*-sysv4*
7026 RS/6000 LynxOS rs6000-*-lynxos*
7030 OS/9000 i[34]86-*-os9k
7031 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
7034 * Hitachi SH7000 and E7000-PC ICE support
7036 There is now support for communicating with the Hitachi E7000-PC ICE.
7037 This is available automatically when GDB is configured for the SH.
7041 As usual, a variety of small fixes and improvements, both generic
7042 and configuration-specific. See the ChangeLog for more detail.
7044 *** Changes in GDB-4.12:
7046 * Irix 5 is now supported
7050 GDB-4.12 on the HPPA has a number of changes which make it unable
7051 to debug the output from the currently released versions of GCC and
7052 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
7053 of GCC and GAS, versions of these tools designed to work with GDB-4.12
7054 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
7057 *** Changes in GDB-4.11:
7059 * User visible changes:
7063 The "set remotedebug" option is now consistent between the mips remote
7064 target, remote targets using the gdb-specific protocol, UDI (AMD's
7065 debug protocol for the 29k) and the 88k bug monitor. It is now an
7066 integer specifying a debug level (normally 0 or 1, but 2 means more
7067 debugging info for the mips target).
7069 * DEC Alpha native support
7071 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
7072 debug info, but GDB works fairly well with the DEC compiler and should
7073 work with a future GCC release. See the README file for a few
7074 Alpha-specific notes.
7076 * Preliminary thread implementation
7078 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
7080 * LynxOS native and target support for 386
7082 This release has been hosted on LynxOS 2.2, and also can be configured
7083 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
7086 * Improvements in C++ mangling/demangling.
7088 This release has much better g++ debugging, specifically in name
7089 mangling/demangling, virtual function calls, print virtual table,
7090 call methods, ...etc.
7092 *** Changes in GDB-4.10:
7094 * User visible changes:
7096 Remote debugging using the GDB-specific (`target remote') protocol now
7097 supports the `load' command. This is only useful if you have some
7098 other way of getting the stub to the target system, and you can put it
7099 somewhere in memory where it won't get clobbered by the download.
7101 Filename completion now works.
7103 When run under emacs mode, the "info line" command now causes the
7104 arrow to point to the line specified. Also, "info line" prints
7105 addresses in symbolic form (as well as hex).
7107 All vxworks based targets now support a user settable option, called
7108 vxworks-timeout. This option represents the number of seconds gdb
7109 should wait for responses to rpc's. You might want to use this if
7110 your vxworks target is, perhaps, a slow software simulator or happens
7111 to be on the far side of a thin network line.
7115 This release contains support for using a DEC alpha as a GDB host for
7116 cross debugging. Native alpha debugging is not supported yet.
7119 *** Changes in GDB-4.9:
7123 This is the first GDB release which is accompanied by a matching testsuite.
7124 The testsuite requires installation of dejagnu, which should be available
7125 via ftp from most sites that carry GNU software.
7129 'Cfront' style demangling has had its name changed to 'ARM' style, to
7130 emphasize that it was written from the specifications in the C++ Annotated
7131 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
7132 disclaimers, it still generated too much confusion with users attempting to
7133 use gdb with AT&T cfront.
7137 GDB now uses a standard remote interface to a simulator library.
7138 So far, the library contains simulators for the Zilog Z8001/2, the
7139 Hitachi H8/300, H8/500 and Super-H.
7141 * New targets supported
7143 H8/300 simulator h8300-hitachi-hms or h8300hms
7144 H8/500 simulator h8500-hitachi-hms or h8500hms
7145 SH simulator sh-hitachi-hms or sh
7146 Z8000 simulator z8k-zilog-none or z8ksim
7147 IDT MIPS board over serial line mips-idt-ecoff
7149 Cross-debugging to GO32 targets is supported. It requires a custom
7150 version of the i386-stub.c module which is integrated with the
7151 GO32 memory extender.
7153 * New remote protocols
7155 MIPS remote debugging protocol.
7157 * New source languages supported
7159 This version includes preliminary support for Chill, a Pascal like language
7160 used by telecommunications companies. Chill support is also being integrated
7161 into the GNU compiler, but we don't know when it will be publically available.
7164 *** Changes in GDB-4.8:
7166 * HP Precision Architecture supported
7168 GDB now supports HP PA-RISC machines running HPUX. A preliminary
7169 version of this support was available as a set of patches from the
7170 University of Utah. GDB does not support debugging of programs
7171 compiled with the HP compiler, because HP will not document their file
7172 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
7173 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
7175 Many problems in the preliminary version have been fixed.
7177 * Faster and better demangling
7179 We have improved template demangling and fixed numerous bugs in the GNU style
7180 demangler. It can now handle type modifiers such as `static' or `const'. Wide
7181 character types (wchar_t) are now supported. Demangling of each symbol is now
7182 only done once, and is cached when the symbol table for a file is read in.
7183 This results in a small increase in memory usage for C programs, a moderate
7184 increase in memory usage for C++ programs, and a fantastic speedup in
7187 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
7188 from the specifications in the Annotated Reference Manual, which AT&T's
7189 compiler does not actually implement.
7191 * G++ multiple inheritance compiler problem
7193 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
7194 inheritance lattices was reworked to properly discover ambiguities. We
7195 recently found an example which causes this new algorithm to fail in a
7196 very subtle way, producing bad debug information for those classes.
7197 The file 'gcc.patch' (in this directory) can be applied to gcc to
7198 circumvent the problem. A future GCC release will contain a complete
7201 The previous G++ debug info problem (mentioned below for the gdb-4.7
7202 release) is fixed in gcc version 2.3.2.
7204 * Improved configure script
7206 The `configure' script will now attempt to guess your system type if
7207 you don't supply a host system type. The old scheme of supplying a
7208 host system triplet is preferable over using this. All the magic is
7209 done in the new `config.guess' script. Examine it for details.
7211 We have also brought our configure script much more in line with the FSF's
7212 version. It now supports the --with-xxx options. In particular,
7213 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
7214 The resulting GDB will not be able to read arbitrary object file formats --
7215 only the format ``expected'' to be used on the configured target system.
7216 We hope to make this the default in a future release.
7218 * Documentation improvements
7220 There's new internal documentation on how to modify GDB, and how to
7221 produce clean changes to the code. We implore people to read it
7222 before submitting changes.
7224 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
7225 M4 macros. The new texinfo.tex is provided in this release. Pre-built
7226 `info' files are also provided. To build `info' files from scratch,
7227 you will need the latest `makeinfo' release, which will be available in
7228 a future texinfo-X.Y release.
7230 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
7231 We're not sure exactly which versions have this problem, but it has
7232 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
7233 or better. If that isn't possible, there is a patch in
7234 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
7235 around this problem.
7239 GDB now supports array constants that can be used in expressions typed in by
7240 the user. The syntax is `{element, element, ...}'. Ie: you can now type
7241 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
7244 The new directory `gdb/sparclite' contains a program that demonstrates
7245 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
7247 * New native hosts supported
7249 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
7250 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
7252 * New targets supported
7254 AMD 29k family via UDI a29k-amd-udi or udi29k
7256 * New file formats supported
7258 BFD now supports reading HP/PA-RISC executables (SOM file format?),
7259 HPUX core files, and SCO 3.2v2 core files.
7263 Attaching to processes now works again; thanks for the many bug reports.
7265 We have also stomped on a bunch of core dumps caused by
7266 printf_filtered("%s") problems.
7268 We eliminated a copyright problem on the rpc and ptrace header files
7269 for VxWorks, which was discovered at the last minute during the 4.7
7270 release. You should now be able to build a VxWorks GDB.
7272 You can now interrupt gdb while an attached process is running. This
7273 will cause the attached process to stop, and give control back to GDB.
7275 We fixed problems caused by using too many file descriptors
7276 for reading symbols from object files and libraries. This was
7277 especially a problem for programs that used many (~100) shared
7280 The `step' command now only enters a subroutine if there is line number
7281 information for the subroutine. Otherwise it acts like the `next'
7282 command. Previously, `step' would enter subroutines if there was
7283 any debugging information about the routine. This avoids problems
7284 when using `cc -g1' on MIPS machines.
7286 * Internal improvements
7288 GDB's internal interfaces have been improved to make it easier to support
7289 debugging of multiple languages in the future.
7291 GDB now uses a common structure for symbol information internally.
7292 Minimal symbols (derived from linkage symbols in object files), partial
7293 symbols (from a quick scan of debug information), and full symbols
7294 contain a common subset of information, making it easier to write
7295 shared code that handles any of them.
7297 * New command line options
7299 We now accept --silent as an alias for --quiet.
7303 The memory-mapped-malloc library is now licensed under the GNU Library
7304 General Public License.
7306 *** Changes in GDB-4.7:
7308 * Host/native/target split
7310 GDB has had some major internal surgery to untangle the support for
7311 hosts and remote targets. Now, when you configure GDB for a remote
7312 target, it will no longer load in all of the support for debugging
7313 local programs on the host. When fully completed and tested, this will
7314 ensure that arbitrary host/target combinations are possible.
7316 The primary conceptual shift is to separate the non-portable code in
7317 GDB into three categories. Host specific code is required any time GDB
7318 is compiled on that host, regardless of the target. Target specific
7319 code relates to the peculiarities of the target, but can be compiled on
7320 any host. Native specific code is everything else: it can only be
7321 built when the host and target are the same system. Child process
7322 handling and core file support are two common `native' examples.
7324 GDB's use of /proc for controlling Unix child processes is now cleaner.
7325 It has been split out into a single module under the `target_ops' vector,
7326 plus two native-dependent functions for each system that uses /proc.
7328 * New hosts supported
7330 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
7331 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7332 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
7334 * New targets supported
7336 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
7337 68030 and CPU32 m68030-*-*, m68332-*-*
7339 * New native hosts supported
7341 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7342 (386bsd is not well tested yet)
7343 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
7345 * New file formats supported
7347 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
7348 supports reading of `a.out.adobe' object files, which are an a.out
7349 format extended with minimal information about multiple sections.
7353 `show copying' is the same as the old `info copying'.
7354 `show warranty' is the same as `info warrantee'.
7355 These were renamed for consistency. The old commands continue to work.
7357 `info handle' is a new alias for `info signals'.
7359 You can now define pre-command hooks, which attach arbitrary command
7360 scripts to any command. The commands in the hook will be executed
7361 prior to the user's command. You can also create a hook which will be
7362 executed whenever the program stops. See gdb.texinfo.
7366 We now deal with Cfront style name mangling, and can even extract type
7367 info from mangled symbols. GDB can automatically figure out which
7368 symbol mangling style your C++ compiler uses.
7370 Calling of methods and virtual functions has been improved as well.
7374 The crash that occurred when debugging Sun Ansi-C compiled binaries is
7375 fixed. This was due to mishandling of the extra N_SO stabs output
7378 We also finally got Ultrix 4.2 running in house, and fixed core file
7379 support, with help from a dozen people on the net.
7381 John M. Farrell discovered that the reason that single-stepping was so
7382 slow on all of the Mips based platforms (primarily SGI and DEC) was
7383 that we were trying to demangle and lookup a symbol used for internal
7384 purposes on every instruction that was being stepped through. Changing
7385 the name of that symbol so that it couldn't be mistaken for a C++
7386 mangled symbol sped things up a great deal.
7388 Rich Pixley sped up symbol lookups in general by getting much smarter
7389 about when C++ symbol mangling is necessary. This should make symbol
7390 completion (TAB on the command line) much faster. It's not as fast as
7391 we'd like, but it's significantly faster than gdb-4.6.
7395 A new user controllable variable 'call_scratch_address' can
7396 specify the location of a scratch area to be used when GDB
7397 calls a function in the target. This is necessary because the
7398 usual method of putting the scratch area on the stack does not work
7399 in systems that have separate instruction and data spaces.
7401 We integrated changes to support the 29k UDI (Universal Debugger
7402 Interface), but discovered at the last minute that we didn't have all
7403 of the appropriate copyright paperwork. We are working with AMD to
7404 resolve this, and hope to have it available soon.
7408 We have sped up the remote serial line protocol, especially for targets
7409 with lots of registers. It now supports a new `expedited status' ('T')
7410 message which can be used in place of the existing 'S' status message.
7411 This allows the remote stub to send only the registers that GDB
7412 needs to make a quick decision about single-stepping or conditional
7413 breakpoints, eliminating the need to fetch the entire register set for
7414 each instruction being stepped through.
7416 The GDB remote serial protocol now implements a write-through cache for
7417 registers, only re-reading the registers if the target has run.
7419 There is also a new remote serial stub for SPARC processors. You can
7420 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
7421 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
7422 processor with a serial port.
7426 Configure.in files have become much easier to read and modify. A new
7427 `table driven' format makes it more obvious what configurations are
7428 supported, and what files each one uses.
7432 There is a new opcodes library which will eventually contain all of the
7433 disassembly routines and opcode tables. At present, it only contains
7434 Sparc and Z8000 routines. This will allow the assembler, debugger, and
7435 disassembler (binutils/objdump) to share these routines.
7437 The libiberty library is now copylefted under the GNU Library General
7438 Public License. This allows more liberal use, and was done so libg++
7439 can use it. This makes no difference to GDB, since the Library License
7440 grants all the rights from the General Public License.
7444 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
7445 reference to the stabs symbol info used by the debugger. It is (as far
7446 as we know) the only published document on this fascinating topic. We
7447 encourage you to read it, compare it to the stabs information on your
7448 system, and send improvements on the document in general (to
7449 bug-gdb@prep.ai.mit.edu).
7451 And, of course, many bugs have been fixed.
7454 *** Changes in GDB-4.6:
7456 * Better support for C++ function names
7458 GDB now accepts as input the "demangled form" of C++ overloaded function
7459 names and member function names, and can do command completion on such names
7460 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
7461 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
7462 Make use of command completion, it is your friend.
7464 GDB also now accepts a variety of C++ mangled symbol formats. They are
7465 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
7466 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
7467 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
7468 for the list of formats.
7470 * G++ symbol mangling problem
7472 Recent versions of gcc have a bug in how they emit debugging information for
7473 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
7474 directory) can be applied to gcc to fix the problem. Alternatively, if you
7475 can't fix gcc, you can #define GCC_MANGLE_BUG when compiling gdb/symtab.c. The
7476 usual symptom is difficulty with setting breakpoints on methods. GDB complains
7477 about the method being non-existent. (We believe that version 2.2.2 of GCC has
7480 * New 'maintenance' command
7482 All of the commands related to hacking GDB internals have been moved out of
7483 the main command set, and now live behind the 'maintenance' command. This
7484 can also be abbreviated as 'mt'. The following changes were made:
7486 dump-me -> maintenance dump-me
7487 info all-breakpoints -> maintenance info breakpoints
7488 printmsyms -> maintenance print msyms
7489 printobjfiles -> maintenance print objfiles
7490 printpsyms -> maintenance print psymbols
7491 printsyms -> maintenance print symbols
7493 The following commands are new:
7495 maintenance demangle Call internal GDB demangler routine to
7496 demangle a C++ link name and prints the result.
7497 maintenance print type Print a type chain for a given symbol
7499 * Change to .gdbinit file processing
7501 We now read the $HOME/.gdbinit file before processing the argv arguments
7502 (e.g. reading symbol files or core files). This allows global parameters to
7503 be set, which will apply during the symbol reading. The ./.gdbinit is still
7504 read after argv processing.
7506 * New hosts supported
7508 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
7510 GNU/Linux support i386-unknown-linux or linux
7512 We are also including code to support the HP/PA running BSD and HPUX. This
7513 is almost guaranteed not to work, as we didn't have time to test or build it
7514 for this release. We are including it so that the more adventurous (or
7515 masochistic) of you can play with it. We also had major problems with the
7516 fact that the compiler that we got from HP doesn't support the -g option.
7519 * New targets supported
7521 Hitachi H8/300 h8300-hitachi-hms or h8300hms
7523 * More smarts about finding #include files
7525 GDB now remembers the compilation directory for all include files, and for
7526 all files from which C is generated (like yacc and lex sources). This
7527 greatly improves GDB's ability to find yacc/lex sources, and include files,
7528 especially if you are debugging your program from a directory different from
7529 the one that contains your sources.
7531 We also fixed a bug which caused difficulty with listing and setting
7532 breakpoints in include files which contain C code. (In the past, you had to
7533 try twice in order to list an include file that you hadn't looked at before.)
7535 * Interesting infernals change
7537 GDB now deals with arbitrary numbers of sections, where the symbols for each
7538 section must be relocated relative to that section's landing place in the
7539 target's address space. This work was needed to support ELF with embedded
7540 stabs used by Solaris-2.0.
7542 * Bug fixes (of course!)
7544 There have been loads of fixes for the following things:
7545 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
7546 i960, stabs, DOS(GO32), procfs, etc...
7548 See the ChangeLog for details.
7550 *** Changes in GDB-4.5:
7552 * New machines supported (host and target)
7554 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
7556 SGI Irix-4.x mips-sgi-irix4 or iris4
7558 * New malloc package
7560 GDB now uses a new memory manager called mmalloc, based on gmalloc.
7561 Mmalloc is capable of handling multiple heaps of memory. It is also
7562 capable of saving a heap to a file, and then mapping it back in later.
7563 This can be used to greatly speedup the startup of GDB by using a
7564 pre-parsed symbol table which lives in a mmalloc managed heap. For
7565 more details, please read mmalloc/mmalloc.texi.
7569 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
7570 'help info proc' for details.
7572 * MIPS ecoff symbol table format
7574 The code that reads MIPS symbol table format is now supported on all hosts.
7575 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
7578 * File name changes for MS-DOS
7580 Many files in the config directories have been renamed to make it easier to
7581 support GDB on MS-DOSe systems (which have very restrictive file name
7582 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
7583 environment) is close to working but has some remaining problems. Note
7584 that debugging of DOS programs is not supported, due to limitations
7585 in the ``operating system'', but it can be used to host cross-debugging.
7587 * Cross byte order fixes
7589 Many fixes have been made to support cross debugging of Sparc and MIPS
7590 targets from hosts whose byte order differs.
7592 * New -mapped and -readnow options
7594 If memory-mapped files are available on your system through the 'mmap'
7595 system call, you can use the -mapped option on the `file' or
7596 `symbol-file' commands to cause GDB to write the symbols from your
7597 program into a reusable file. If the program you are debugging is
7598 called `/path/fred', the mapped symbol file will be `./fred.syms'.
7599 Future GDB debugging sessions will notice the presence of this file,
7600 and will quickly map in symbol information from it, rather than reading
7601 the symbol table from the executable program. Using the '-mapped'
7602 option in a GDB `file' or `symbol-file' command has the same effect as
7603 starting GDB with the '-mapped' command-line option.
7605 You can cause GDB to read the entire symbol table immediately by using
7606 the '-readnow' option with any of the commands that load symbol table
7607 information (or on the GDB command line). This makes the command
7608 slower, but makes future operations faster.
7610 The -mapped and -readnow options are typically combined in order to
7611 build a `fred.syms' file that contains complete symbol information.
7612 A simple GDB invocation to do nothing but build a `.syms' file for future
7615 gdb -batch -nx -mapped -readnow programname
7617 The `.syms' file is specific to the host machine on which GDB is run.
7618 It holds an exact image of GDB's internal symbol table. It cannot be
7619 shared across multiple host platforms.
7621 * longjmp() handling
7623 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
7624 siglongjmp() without losing control. This feature has not yet been ported to
7625 all systems. It currently works on many 386 platforms, all MIPS-based
7626 platforms (SGI, DECstation, etc), and Sun3/4.
7630 Preliminary work has been put in to support the new Solaris OS from Sun. At
7631 this time, it can control and debug processes, but it is not capable of
7636 As always, many many bug fixes. The major areas were with g++, and mipsread.
7637 People using the MIPS-based platforms should experience fewer mysterious
7638 crashes and trashed symbol tables.
7640 *** Changes in GDB-4.4:
7642 * New machines supported (host and target)
7644 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7646 BSD Reno on Vax vax-dec-bsd
7647 Ultrix on Vax vax-dec-ultrix
7649 * New machines supported (target)
7651 AMD 29000 embedded, using EBMON a29k-none-none
7655 GDB continues to improve its handling of C++. `References' work better.
7656 The demangler has also been improved, and now deals with symbols mangled as
7657 per the Annotated C++ Reference Guide.
7659 GDB also now handles `stabs' symbol information embedded in MIPS
7660 `ecoff' symbol tables. Since the ecoff format was not easily
7661 extensible to handle new languages such as C++, this appeared to be a
7662 good way to put C++ debugging info into MIPS binaries. This option
7663 will be supported in the GNU C compiler, version 2, when it is
7666 * New features for SVR4
7668 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7669 shared libraries. Debugging dynamically linked programs should present
7670 only minor differences from debugging statically linked programs.
7672 The `info proc' command will print out information about any process
7673 on an SVR4 system (including the one you are debugging). At the moment,
7674 it prints the address mappings of the process.
7676 If you bring up GDB on another SVR4 system, please send mail to
7677 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7679 * Better dynamic linking support in SunOS
7681 Reading symbols from shared libraries which contain debugging symbols
7682 now works properly. However, there remain issues such as automatic
7683 skipping of `transfer vector' code during function calls, which
7684 make it harder to debug code in a shared library, than to debug the
7685 same code linked statically.
7689 GDB is now using the latest `getopt' routines from the FSF. This
7690 version accepts the -- prefix for options with long names. GDB will
7691 continue to accept the old forms (-option and +option) as well.
7692 Various single letter abbreviations for options have been explicity
7693 added to the option table so that they won't get overshadowed in the
7694 future by other options that begin with the same letter.
7698 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7699 Many assorted bugs have been handled. Many more remain to be handled.
7700 See the various ChangeLog files (primarily in gdb and bfd) for details.
7703 *** Changes in GDB-4.3:
7705 * New machines supported (host and target)
7707 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7708 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7709 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7711 * Almost SCO Unix support
7713 We had hoped to support:
7714 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7715 (except for core file support), but we discovered very late in the release
7716 that it has problems with process groups that render gdb unusable. Sorry
7717 about that. I encourage people to fix it and post the fixes.
7719 * Preliminary ELF and DWARF support
7721 GDB can read ELF object files on System V Release 4, and can handle
7722 debugging records for C, in DWARF format, in ELF files. This support
7723 is preliminary. If you bring up GDB on another SVR4 system, please
7724 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7729 GDB now uses the latest `readline' library. One user-visible change
7730 is that two tabs will list possible command completions, which previously
7731 required typing M-? (meta-question mark, or ESC ?).
7735 The `stepi' bug that many of you noticed has been squashed.
7736 Many bugs in C++ have been handled. Many more remain to be handled.
7737 See the various ChangeLog files (primarily in gdb and bfd) for details.
7739 * State of the MIPS world (in case you wondered):
7741 GDB can understand the symbol tables emitted by the compilers
7742 supplied by most vendors of MIPS-based machines, including DEC. These
7743 symbol tables are in a format that essentially nobody else uses.
7745 Some versions of gcc come with an assembler post-processor called
7746 mips-tfile. This program is required if you want to do source-level
7747 debugging of gcc-compiled programs. I believe FSF does not ship
7748 mips-tfile with gcc version 1, but it will eventually come with gcc
7751 Debugging of g++ output remains a problem. g++ version 1.xx does not
7752 really support it at all. (If you're lucky, you should be able to get
7753 line numbers and stack traces to work, but no parameters or local
7754 variables.) With some work it should be possible to improve the
7757 When gcc version 2 is released, you will have somewhat better luck.
7758 However, even then you will get confusing results for inheritance and
7761 We will eventually provide full debugging of g++ output on
7762 DECstations. This will probably involve some kind of stabs-in-ecoff
7763 encapulation, but the details have not been worked out yet.
7766 *** Changes in GDB-4.2:
7768 * Improved configuration
7770 Only one copy of `configure' exists now, and it is not self-modifying.
7771 Porting BFD is simpler.
7775 The `step' and `next' commands now only stop at the first instruction
7776 of a source line. This prevents the multiple stops that used to occur
7777 in switch statements, for-loops, etc. `Step' continues to stop if a
7778 function that has debugging information is called within the line.
7782 Lots of small bugs fixed. More remain.
7784 * New host supported (not target)
7786 Intel 386 PC clone running Mach i386-none-mach
7789 *** Changes in GDB-4.1:
7791 * Multiple source language support
7793 GDB now has internal scaffolding to handle several source languages.
7794 It determines the type of each source file from its filename extension,
7795 and will switch expression parsing and number formatting to match the
7796 language of the function in the currently selected stack frame.
7797 You can also specifically set the language to be used, with
7798 `set language c' or `set language modula-2'.
7802 GDB now has preliminary support for the GNU Modula-2 compiler,
7803 currently under development at the State University of New York at
7804 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7805 continue through the fall of 1991 and into 1992.
7807 Other Modula-2 compilers are currently not supported, and attempting to
7808 debug programs compiled with them will likely result in an error as the
7809 symbol table is read. Feel free to work on it, though!
7811 There are hooks in GDB for strict type checking and range checking,
7812 in the `Modula-2 philosophy', but they do not currently work.
7816 GDB can now write to executable and core files (e.g. patch
7817 a variable's value). You must turn this switch on, specify
7818 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7819 by assigning a new value to a variable. Modifications take
7822 * Automatic SunOS shared library reading
7824 When you run your program, GDB automatically determines where its
7825 shared libraries (if any) have been loaded, and reads their symbols.
7826 The `share' command is no longer needed. This also works when
7827 examining core files.
7831 You can specify the number of lines that the `list' command shows.
7834 * New machines supported (host and target)
7836 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7837 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7838 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7840 * New hosts supported (not targets)
7842 IBM RT/PC: romp-ibm-aix or rtpc
7844 * New targets supported (not hosts)
7846 AMD 29000 embedded with COFF a29k-none-coff
7847 AMD 29000 embedded with a.out a29k-none-aout
7848 Ultracomputer remote kernel debug a29k-nyu-kern
7850 * New remote interfaces
7856 *** Changes in GDB-4.0:
7860 Wide output is wrapped at good places to make the output more readable.
7862 Gdb now supports cross-debugging from a host machine of one type to a
7863 target machine of another type. Communication with the target system
7864 is over serial lines. The ``target'' command handles connecting to the
7865 remote system; the ``load'' command will download a program into the
7866 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7867 also supports debugging of realtime processes running under VxWorks,
7868 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7869 stub on the target system.
7871 New CPUs supported include the AMD 29000 and Intel 960.
7873 GDB now reads object files and symbol tables via a ``binary file''
7874 library, which allows a single copy of GDB to debug programs of multiple
7875 object file types such as a.out and coff.
7877 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7878 refcard.dvi and refcard.ps are available to format it).
7881 * Control-Variable user interface simplified
7883 All variables that control the operation of the debugger can be set
7884 by the ``set'' command, and displayed by the ``show'' command.
7886 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7887 ``Show prompt'' produces the response:
7888 Gdb's prompt is new-gdb=>.
7890 What follows are the NEW set commands. The command ``help set'' will
7891 print a complete list of old and new set commands. ``help set FOO''
7892 will give a longer description of the variable FOO. ``show'' will show
7893 all of the variable descriptions and their current settings.
7895 confirm on/off: Enables warning questions for operations that are
7896 hard to recover from, e.g. rerunning the program while
7897 it is already running. Default is ON.
7899 editing on/off: Enables EMACS style command line editing
7900 of input. Previous lines can be recalled with
7901 control-P, the current line can be edited with control-B,
7902 you can search for commands with control-R, etc.
7905 history filename NAME: NAME is where the gdb command history
7906 will be stored. The default is .gdb_history,
7907 or the value of the environment variable
7910 history size N: The size, in commands, of the command history. The
7911 default is 256, or the value of the environment variable
7914 history save on/off: If this value is set to ON, the history file will
7915 be saved after exiting gdb. If set to OFF, the
7916 file will not be saved. The default is OFF.
7918 history expansion on/off: If this value is set to ON, then csh-like
7919 history expansion will be performed on
7920 command line input. The default is OFF.
7922 radix N: Sets the default radix for input and output. It can be set
7923 to 8, 10, or 16. Note that the argument to "radix" is interpreted
7924 in the current radix, so "set radix 10" is always a no-op.
7926 height N: This integer value is the number of lines on a page. Default
7927 is 24, the current `stty rows'' setting, or the ``li#''
7928 setting from the termcap entry matching the environment
7931 width N: This integer value is the number of characters on a line.
7932 Default is 80, the current `stty cols'' setting, or the ``co#''
7933 setting from the termcap entry matching the environment
7936 Note: ``set screensize'' is obsolete. Use ``set height'' and
7937 ``set width'' instead.
7939 print address on/off: Print memory addresses in various command displays,
7940 such as stack traces and structure values. Gdb looks
7941 more ``symbolic'' if you turn this off; it looks more
7942 ``machine level'' with it on. Default is ON.
7944 print array on/off: Prettyprint arrays. New convenient format! Default
7947 print demangle on/off: Print C++ symbols in "source" form if on,
7950 print asm-demangle on/off: Same, for assembler level printouts
7953 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7956 * Support for Epoch Environment.
7958 The epoch environment is a version of Emacs v18 with windowing. One
7959 new command, ``inspect'', is identical to ``print'', except that if you
7960 are running in the epoch environment, the value is printed in its own
7964 * Support for Shared Libraries
7966 GDB can now debug programs and core files that use SunOS shared libraries.
7967 Symbols from a shared library cannot be referenced
7968 before the shared library has been linked with the program (this
7969 happens after you type ``run'' and before the function main() is entered).
7970 At any time after this linking (including when examining core files
7971 from dynamically linked programs), gdb reads the symbols from each
7972 shared library when you type the ``sharedlibrary'' command.
7973 It can be abbreviated ``share''.
7975 sharedlibrary REGEXP: Load shared object library symbols for files
7976 matching a unix regular expression. No argument
7977 indicates to load symbols for all shared libraries.
7979 info sharedlibrary: Status of loaded shared libraries.
7984 A watchpoint stops execution of a program whenever the value of an
7985 expression changes. Checking for this slows down execution
7986 tremendously whenever you are in the scope of the expression, but is
7987 quite useful for catching tough ``bit-spreader'' or pointer misuse
7988 problems. Some machines such as the 386 have hardware for doing this
7989 more quickly, and future versions of gdb will use this hardware.
7991 watch EXP: Set a watchpoint (breakpoint) for an expression.
7993 info watchpoints: Information about your watchpoints.
7995 delete N: Deletes watchpoint number N (same as breakpoints).
7996 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7997 enable N: Re-enables watchpoint number N (same as breakpoints).
8000 * C++ multiple inheritance
8002 When used with a GCC version 2 compiler, GDB supports multiple inheritance
8005 * C++ exception handling
8007 Gdb now supports limited C++ exception handling. Besides the existing
8008 ability to breakpoint on an exception handler, gdb can breakpoint on
8009 the raising of an exception (before the stack is peeled back to the
8012 catch FOO: If there is a FOO exception handler in the dynamic scope,
8013 set a breakpoint to catch exceptions which may be raised there.
8014 Multiple exceptions (``catch foo bar baz'') may be caught.
8016 info catch: Lists all exceptions which may be caught in the
8017 current stack frame.
8020 * Minor command changes
8022 The command ``call func (arg, arg, ...)'' now acts like the print
8023 command, except it does not print or save a value if the function's result
8024 is void. This is similar to dbx usage.
8026 The ``up'' and ``down'' commands now always print the frame they end up
8027 at; ``up-silently'' and `down-silently'' can be used in scripts to change
8028 frames without printing.
8030 * New directory command
8032 'dir' now adds directories to the FRONT of the source search path.
8033 The path starts off empty. Source files that contain debug information
8034 about the directory in which they were compiled can be found even
8035 with an empty path; Sun CC and GCC include this information. If GDB can't
8036 find your source file in the current directory, type "dir .".
8038 * Configuring GDB for compilation
8040 For normal use, type ``./configure host''. See README or gdb.texinfo
8043 GDB now handles cross debugging. If you are remotely debugging between
8044 two different machines, type ``./configure host -target=targ''.
8045 Host is the machine where GDB will run; targ is the machine
8046 where the program that you are debugging will run.