1 What has changed in GDB?
2 (Organized release by release)
6 * The 'set disassembler-options' command now supports specifying options
9 * GDB now supports general memory tagging functionality if the underlying
10 architecture supports the proper primitives and hooks. Currently this is
11 enabled only for AArch64 MTE.
15 - Additional information when the inferior crashes with a SIGSEGV caused by
16 a memory tag violation.
18 - A new modifier 'm' for the "x" command, which displays allocation tags for a
19 particular memory range.
21 - Display of memory tag mismatches by "print", for addresses and
22 pointers, if memory tagging is supported by the architecture.
24 * Building GDB now requires GMP (The GNU Multiple Precision Arithmetic
29 ** '-break-insert --qualified' and '-dprintf-insert --qualified'
31 The MI -break-insert and -dprintf-insert commands now support a
32 new "--qualified" option that makes GDB interpret a specified
33 function name as a complete fully-qualified name. This is the
34 equivalent of the CLI's "break -qualified" and "dprintf
37 ** '-break-insert --force-condition' and '-dprintf-insert --force-condition'
39 The MI -break-insert and -dprintf-insert commands now support a
40 '--force-condition' flag to forcibly define a condition even when
41 the condition is invalid at all locations of the breakpoint. This
42 is equivalent to the '-force-condition' flag of the CLI's "break"
45 ** '-break-condition --force'
47 The MI -break-condition command now supports a '--force' flag to
48 forcibly define a condition even when the condition is invalid at
49 all locations of the selected breakpoint. This is equivalent to
50 the '-force' flag of the CLI's "cond" command.
52 ** '-file-list-exec-source-files [--group-by-objfile]
53 [--basename | --dirname]
56 The existing -file-list-exec-source-files command now takes an
57 optional REGEXP which is used to filter the source files that are
58 included in the results.
60 By default REGEXP is matched against the full filename of the
61 source file. When one of --basename or --dirname is given then
62 REGEXP is only matched against the specified part of the full
65 When the optional --group-by-objfile flag is used the output
66 format is changed, the results are now a list of object files
67 (executable and libraries) with the source files that are
68 associated with each object file.
70 The results from -file-list-exec-source-files now include a
71 'debug-fully-read' field which takes the value 'true' or 'false'.
72 A 'true' value indicates the source file is from a compilation
73 unit that has had its debug information fully read in by GDB, a
74 value of 'false' indicates GDB has only performed a partial scan
75 of the debug information so far.
77 * GDB now supports core file debugging for x86_64 Cygwin programs.
79 * GDB will now look for the .gdbinit file in a config directory before
80 looking for ~/.gdbinit. The file is searched for in the following
81 locations: $XDG_CONFIG_HOME/gdb/gdbinit, $HOME/.config/gdb/gdbinit,
82 $HOME/.gdbinit. On Apple hosts the search order is instead:
83 $HOME/Library/Preferences/gdb/gdbinit, $HOME/.gdbinit.
85 * GDB now supports fixed point types which are described in DWARF
86 as base types with a fixed-point encoding. Additionally, support
87 for the DW_AT_GNU_numerator and DW_AT_GNU_denominator has also
90 For Ada, this allows support for fixed point types without requiring
91 the use of the GNAT encoding (based on information added to the type's
92 name following a GNAT-specific format).
94 * GDB will now load and process commands from ~/.config/gdb/gdbearlyinit
95 or ~/.gdbearlyinit if these files are present. These files are
96 processed earlier than any of the other initialization files and
97 can affect parts of GDB's startup that previously had already been
98 completed before the initialization files were read, for example
99 styling of the initial GDB greeting.
101 * GDB now has two new options "--early-init-command" and
102 "--early-init-eval-command" with corresponding short options "-eix"
103 and "-eiex" that allow options (that would normally appear in a
104 gdbearlyinit file) to be passed on the command line.
106 * For RISC-V targets, the target feature "org.gnu.gdb.riscv.vector" is
107 now understood by GDB, and can be used to describe the vector
108 registers of a target. The precise requirements of this register
109 feature are documented in the GDB manual.
113 ** TUI windows now support mouse actions. The mouse wheel scrolls
114 the appropriate window.
116 ** Key combinations that do not have a specific action on the
117 focused window are passed to GDB. For example, you now can use
118 Ctrl-Left/Ctrl-Right to move between words in the command window
119 regardless of which window is in focus. Previously you would
120 need to focus on the command window for such key combinations to
126 show debug event-loop
127 Control the display of debug output about GDB's event loop.
129 set print memory-tag-violations
130 show print memory-tag-violations
131 Control whether to display additional information about memory tag violations
132 when printing pointers and addresses. Architecture support for memory
133 tagging is required for this option to have an effect.
135 maintenance flush symbol-cache
136 maintenance flush register-cache
137 These new commands are equivalent to the already existing commands
138 'maintenance flush-symbol-cache' and 'flushregs' respectively.
140 maintenance flush dcache
141 A new command to flush the dcache.
143 maintenance info target-sections
144 Print GDB's internal target sections table.
146 memory-tag show-logical-tag POINTER
147 Print the logical tag for POINTER.
148 memory-tag with-logical-tag POINTER TAG
149 Print POINTER with logical tag TAG.
150 memory-tag show-allocation-tag ADDRESS
151 Print the allocation tag for ADDRESS.
152 memory-tag set-allocation-tag ADDRESS LENGTH TAGS
153 Set the allocation tag for [ADDRESS, ADDRESS + LENGTH) to TAGS.
154 memory-tag check POINTER
155 Validate that POINTER's logical tag matches the allocation tag.
157 set startup-quietly on|off
159 When 'on', this causes GDB to act as if "-silent" were passed on the
160 command line. This command needs to be added to an early
161 initialization file (e.g. ~/.config/gdb/gdbearlyinit) in order to
164 set print type hex on|off
166 When 'on', the 'ptype' command uses hexadecimal notation to print sizes
167 and offsets of struct members. When 'off', decimal notation is used.
169 set python ignore-environment on|off
170 show python ignore-environment
171 When 'on', this causes GDB's builtin Python to ignore any
172 environment variables that would otherwise affect how Python
173 behaves. This command needs to be added to an early initialization
174 file (e.g. ~/.config/gdb/gdbearlyinit) in order to affect GDB.
176 set python dont-write-bytecode auto|on|off
177 show python dont-write-bytecode
178 When 'on', this causes GDB's builtin Python to not write any
179 byte-code (.pyc files) to disk. This command needs to be added to
180 an early initialization file (e.g. ~/.config/gdb/gdbearlyinit) in
181 order to affect GDB. When 'off' byte-code will always be written.
182 When set to 'auto' (the default) Python will check the
183 PYTHONDONTWRITEBYTECODE environment variable.
187 break [PROBE_MODIFIER] [LOCATION] [thread THREADNUM]
188 [-force-condition] [if CONDITION]
189 This command would previously refuse setting a breakpoint if the
190 CONDITION expression is invalid at a location. It now accepts and
191 defines the breakpoint if there is at least one location at which
192 the CONDITION is valid. The locations for which the CONDITION is
193 invalid, are automatically disabled. If CONDITION is invalid at all
194 of the locations, setting the breakpoint is still rejected. However,
195 the '-force-condition' flag can be used in this case for forcing GDB to
196 define the breakpoint, making all the current locations automatically
197 disabled. This may be useful if the user knows the condition will
198 become meaningful at a future location, e.g. due to a shared library
201 condition [-force] N COND
202 The behavior of this command is changed the same way for the 'break'
203 command as explained above. The '-force' flag can be used to force
204 GDB into defining the condition even when COND is invalid for all the
205 current locations of breakpoint N.
208 maintenance flush-symbol-cache
209 These commands are deprecated in favor of the new commands
210 'maintenance flush register-cache' and 'maintenance flush
211 symbol-cache' respectively.
213 set style version foreground COLOR
214 set style version background COLOR
215 set style version intensity VALUE
216 Control the styling of GDB's version number text.
219 When the ID parameter is omitted, then this command prints information
220 about the current inferior. When the ID parameter is present, the
221 behavior of the command is unchanged and have the inferior ID become
222 the current inferior.
224 maintenance info sections
225 The ALLOBJ keyword has been replaced with an -all-objects command
226 line flag. It is now possible to filter which sections are printed
227 even when -all-objects is passed.
229 ptype[/FLAGS] TYPE | EXPRESSION
230 The 'ptype' command has two new flags. When '/x' is set, hexadecimal
231 notation is used when printing sizes and offsets of struct members.
232 When '/d' is set, decimal notation is used when printing sizes and
233 offsets of struct members. Default behavior is given by 'show print
237 The info sources command output has been restructured. The results
238 are now based around a list of objfiles (executable and libraries),
239 and for each objfile the source files that are part of that objfile
242 * Removed targets and native configurations
244 ARM Symbian arm*-*-symbianelf*
249 Request the remote to send allocation tags for a particular memory range.
251 Request the remote to store the specified allocation tags to the requested
256 ** Improved support for rvalue reference values:
257 TYPE_CODE_RVALUE_REF is now exported as part of the API and the
258 value-referenced-value procedure now handles rvalue reference
261 ** New procedures for obtaining value variants:
262 value-reference-value, value-rvalue-reference-value and
267 ** Inferior objects now contain a read-only 'connection_num' attribute that
268 gives the connection number as seen in 'info connections' and
271 ** New method gdb.Frame.level() which returns the stack level of the
274 ** New method gdb.PendingFrame.level() which returns the stack level
277 ** When hitting a catchpoint, the Python API will now emit a
278 gdb.BreakpointEvent rather than a gdb.StopEvent. The
279 gdb.Breakpoint attached to the event will have type BP_CATCHPOINT.
281 ** Python TUI windows can now receive mouse click events. If the
282 Window object implements the click method, it is called for each
283 mouse click event in this window.
285 *** Changes in GDB 10
287 * There are new feature names for ARC targets: "org.gnu.gdb.arc.core"
288 and "org.gnu.gdb.arc.aux". The old names are still supported but
289 must be considered obsolete. They will be deprecated after some
292 * Help and apropos commands will now show the documentation of a
293 command only once, even if that command has one or more aliases.
294 These commands now show the command name, then all of its aliases,
295 and finally the description of the command.
297 * 'help aliases' now shows only the user defined aliases. GDB predefined
298 aliases are shown together with their aliased command.
300 * GDB now supports debuginfod, an HTTP server for distributing ELF/DWARF
301 debugging information as well as source code.
303 When built with debuginfod, GDB can automatically query debuginfod
304 servers for the separate debug files and source code of the executable
307 To build GDB with debuginfod, pass --with-debuginfod to configure (this
308 requires libdebuginfod, the debuginfod client library).
310 debuginfod is distributed with elfutils, starting with version 0.178.
312 You can get the latest version from https://sourceware.org/elfutils.
314 * Multi-target debugging support
316 GDB now supports debugging multiple target connections
317 simultaneously. For example, you can now have each inferior
318 connected to different remote servers running in different machines,
319 or have one inferior debugging a local native process, an inferior
320 debugging a core dump, etc.
322 This support is experimental and comes with some limitations -- you
323 can only resume multiple targets simultaneously if all targets
324 support non-stop mode, and all remote stubs or servers must support
325 the same set of remote protocol features exactly. See also "info
326 connections" and "add-inferior -no-connection" below, and "maint set
327 target-non-stop" in the user manual.
329 * New features in the GDB remote stub, GDBserver
331 ** GDBserver is now supported on ARC GNU/Linux.
333 ** GDBserver is now supported on RISC-V GNU/Linux.
335 ** GDBserver no longer supports these host triplets:
346 i[34567]86-*-mingw32ce*
348 * Debugging MS-Windows processes now sets $_exitsignal when the
349 inferior is terminated by a signal, instead of setting $_exitcode.
351 * Multithreaded symbol loading has now been enabled by default on systems
352 that support it (see entry for GDB 9, below), providing faster
353 performance for programs with many symbols.
355 * The $_siginfo convenience variable now also works on Windows targets,
356 and will display the EXCEPTION_RECORD of the last handled exception.
358 * TUI windows can now be arranged horizontally.
360 * The command history filename can now be set to the empty string
361 either using 'set history filename' or by setting 'GDBHISTFILE=' in
362 the environment. The effect of setting this filename to the empty
363 string is that GDB will not try to load any previous command
366 * On Windows targets, it is now possible to debug 32-bit programs with a
371 set exec-file-mismatch -- Set exec-file-mismatch handling (ask|warn|off).
372 show exec-file-mismatch -- Show exec-file-mismatch handling (ask|warn|off).
373 Set or show the option 'exec-file-mismatch'. When GDB attaches to a
374 running process, this new option indicates whether to detect
375 a mismatch between the current executable file loaded by GDB and the
376 executable file used to start the process. If 'ask', the default,
377 display a warning and ask the user whether to load the process
378 executable file; if 'warn', just display a warning; if 'off', don't
379 attempt to detect a mismatch.
381 tui new-layout NAME WINDOW WEIGHT [WINDOW WEIGHT]...
382 Define a new TUI layout, specifying its name and the windows that
385 maintenance print xml-tdesc [FILE]
386 Prints the current target description as an XML document. If the
387 optional FILE is provided (which is an XML target description) then
388 the target description is read from FILE into GDB, and then
391 maintenance print core-file-backed-mappings
392 Prints file-backed mappings loaded from a core file's note section.
393 Output is expected to be similar to that of "info proc mappings".
395 set debug fortran-array-slicing on|off
396 show debug fortran-array-slicing
397 Print debugging when taking slices of Fortran arrays.
399 set fortran repack-array-slices on|off
400 show fortran repack-array-slices
401 When taking slices from Fortran arrays and strings, if the slice is
402 non-contiguous within the original value then, when this option is
403 on, the new value will be repacked into a single contiguous value.
404 When this option is off, then the value returned will consist of a
405 descriptor that describes the slice within the memory of the
406 original parent value.
410 alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
411 The alias command can now specify default args for an alias.
412 GDB automatically prepends the alias default args to the argument list
413 provided explicitly by the user.
414 For example, to have a backtrace with full details, you can define
416 'alias bt_ALL = backtrace -entry-values both -frame-arg all
417 -past-main -past-entry -full'.
418 Alias default arguments can also use a set of nested 'with' commands,
419 e.g. 'alias pp10 = with print pretty -- with print elem 10 -- print'
420 defines the alias pp10 that will pretty print a maximum of 10 elements
421 of the given expression (if the expression is an array).
425 GNU/Linux/RISC-V (gdbserver) riscv*-*-linux*
431 ** gdb.register_window_type can be used to implement new TUI windows
434 ** Dynamic types can now be queried. gdb.Type has a new attribute,
435 "dynamic", and gdb.Type.sizeof can be None for a dynamic type. A
436 field of a dynamic type may have None for its "bitpos" attribute
439 ** Commands written in Python can be in the "TUI" help class by
440 registering with the new constant gdb.COMMAND_TUI.
442 ** New method gdb.PendingFrame.architecture () to retrieve the
443 architecture of the pending frame.
445 ** New gdb.Architecture.registers method that returns a
446 gdb.RegisterDescriptorIterator object, an iterator that returns
447 gdb.RegisterDescriptor objects. The new RegisterDescriptor is a
448 way to query the registers available for an architecture.
450 ** New gdb.Architecture.register_groups method that returns a
451 gdb.RegisterGroupIterator object, an iterator that returns
452 gdb.RegisterGroup objects. The new RegisterGroup is a way to
453 discover the available register groups.
457 ** GDB can now be built with GNU Guile 3.0 and 2.2 in addition to 2.0.
459 ** Procedures 'memory-port-read-buffer-size',
460 'set-memory-port-read-buffer-size!', 'memory-port-write-buffer-size',
461 and 'set-memory-port-write-buffer-size!' are deprecated. When
462 using Guile 2.2 and later, users who need to control the size of
463 a memory port's internal buffer can use the 'setvbuf' procedure.
467 * 'thread-exited' event is now available in the annotations interface.
469 * New built-in convenience variables $_gdb_major and $_gdb_minor
470 provide the GDB version. They are handy for conditionally using
471 features available only in or since specific GDB versions, in
472 scripts that should work error-free with many different versions,
473 such as in system-wide init files.
475 * New built-in convenience functions $_gdb_setting, $_gdb_setting_str,
476 $_gdb_maint_setting and $_gdb_maint_setting_str provide access to values
477 of the GDB settings and the GDB maintenance settings. They are handy
478 for changing the logic of user defined commands depending on the
479 current GDB settings.
481 * GDB now supports Thread Local Storage (TLS) variables on several
482 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
483 architectures require kernel changes. TLS is not yet supported for
484 amd64 and i386 process core dumps.
486 * Support for Pointer Authentication (PAC) on AArch64 Linux. Return
487 addresses that required unmasking are shown in the backtrace with the
490 * Two new convenience functions $_cimag and $_creal that extract the
491 imaginary and real parts respectively from complex numbers.
493 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
494 provide the exitcode or exit status of the shell commands launched by
495 GDB commands such as "shell", "pipe" and "make".
497 * The command define-prefix can now define user defined prefix commands.
498 User defined commands can now be defined using these user defined prefix
501 * Command names can now use the . character.
503 * The RX port now supports XML target descriptions.
505 * GDB now shows the Ada task names at more places, e.g. in task switching
508 * GDB can now be compiled with Python 3 on Windows.
510 * New convenience variable $_ada_exception holds the address of the
511 Ada exception being thrown. This is set by Ada-related catchpoints.
513 * GDB can now place breakpoints on nested functions and subroutines in
514 Fortran code. The '::' operator can be used between parent and
515 child scopes when placing breakpoints, for example:
517 (gdb) break outer_function::inner_function
519 The 'outer_function::' prefix is only needed if 'inner_function' is
520 not visible in the current scope.
522 * In addition to the system-wide gdbinit file, if configured with
523 --with-system-gdbinit-dir, GDB will now also load files in that directory
524 as system gdbinit files, unless the -nx or -n flag is provided. Files
525 with extensions .gdb, .py and .scm are supported as long as GDB was
526 compiled with support for that language.
528 * GDB now supports multithreaded symbol loading for higher performance.
529 This feature is still in testing, so it is disabled by default. You
530 can turn it on using 'maint set worker-threads unlimited'.
534 ** The gdb.Value type has a new method 'format_string' which returns a
535 string representing the value. The formatting is controlled by the
536 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
537 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
538 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
540 ** gdb.Type has a new property 'objfile' which returns the objfile the
543 ** The frame information printed by the python frame filtering code
544 is now consistent with what the 'backtrace' command prints when
545 there are no filters, or when the 'backtrace' '-no-filters' option
548 ** The new function gdb.lookup_static_symbol can be used to look up
549 symbols with static linkage.
551 ** The new function gdb.lookup_static_symbols can be used to look up
552 all static symbols with static linkage.
554 ** gdb.Objfile has new methods 'lookup_global_symbol' and
555 'lookup_static_symbol' to lookup a symbol from this objfile only.
557 ** gdb.Block now supports the dictionary syntax for accessing symbols in
558 this block (e.g. block['local_variable']).
562 | [COMMAND] | SHELL_COMMAND
563 | -d DELIM COMMAND DELIM SHELL_COMMAND
564 pipe [COMMAND] | SHELL_COMMAND
565 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
566 Executes COMMAND and sends its output to SHELL_COMMAND.
567 With no COMMAND, repeat the last executed command
568 and send its output to SHELL_COMMAND.
570 define-prefix COMMAND
571 Define or mark a command as a user-defined prefix command.
573 with SETTING [VALUE] [-- COMMAND]
574 w SETTING [VALUE] [-- COMMAND]
575 Temporarily set SETTING, run COMMAND, and restore SETTING.
576 Usage: with SETTING -- COMMAND
577 With no COMMAND, repeats the last executed command.
578 SETTING is any GDB setting you can change with the "set"
579 subcommands. For example, 'with language c -- print someobj'
580 temporarily switches to the C language in order to print someobj.
581 Settings can be combined: 'w lang c -- w print elements unlimited --
582 usercmd' switches to the C language and runs usercmd with no limit
583 of array elements to print.
585 maint with SETTING [VALUE] [-- COMMAND]
586 Like "with", but works with "maintenance set" settings.
588 set may-call-functions [on|off]
589 show may-call-functions
590 This controls whether GDB will attempt to call functions in
591 the program, such as with expressions in the print command. It
592 defaults to on. Calling functions in the program being debugged
593 can have undesired side effects. It is now possible to forbid
594 such function calls. If function calls are forbidden, GDB will throw
595 an error when a command (such as print expression) calls a function
598 set print finish [on|off]
600 This controls whether the `finish' command will display the value
601 that is returned by the current function. When `off', the value is
602 still entered into the value history, but it is not printed. The
607 Allows deeply nested structures to be simplified when printing by
608 replacing deeply nested parts (beyond the max-depth) with ellipses.
609 The default max-depth is 20, but this can be set to unlimited to get
610 the old behavior back.
612 set print raw-values [on|off]
613 show print raw-values
614 By default, GDB applies the enabled pretty printers when printing a
615 value. This allows to ignore the enabled pretty printers for a series
616 of commands. The default is 'off'.
618 set logging debugredirect [on|off]
619 By default, GDB debug output will go to both the terminal and the logfile.
620 Set if you want debug output to go only to the log file.
622 set style title foreground COLOR
623 set style title background COLOR
624 set style title intensity VALUE
625 Control the styling of titles.
627 set style highlight foreground COLOR
628 set style highlight background COLOR
629 set style highlight intensity VALUE
630 Control the styling of highlightings.
632 maint set worker-threads
633 maint show worker-threads
634 Control the number of worker threads that can be used by GDB. The
635 default is 0. "unlimited" lets GDB choose a number that is
636 reasonable. Currently worker threads are only used when demangling
637 the names of linker symbols.
639 set style tui-border foreground COLOR
640 set style tui-border background COLOR
641 Control the styling of TUI borders.
643 set style tui-active-border foreground COLOR
644 set style tui-active-border background COLOR
645 Control the styling of the active TUI border.
647 maint set test-settings KIND
648 maint show test-settings KIND
649 A set of commands used by the testsuite for exercising the settings
652 maint set tui-resize-message [on|off]
653 maint show tui-resize-message
654 Control whether GDB prints a message each time the terminal is
655 resized when in TUI mode. This is primarily useful for testing the
658 set print frame-info [short-location|location|location-and-address
659 |source-and-location|source-line|auto]
660 show print frame-info
661 This controls what frame information is printed by the commands printing
662 a frame. This setting will e.g. influence the behaviour of 'backtrace',
663 'frame', 'stepi'. The python frame filtering also respect this setting.
664 The 'backtrace' '-frame-info' option can override this global setting.
666 set tui compact-source
667 show tui compact-source
669 Enable the "compact" display mode for the TUI source window. The
670 compact display uses only as much space as is needed for the line
671 numbers in the current file, and only a single space to separate the
672 line numbers from the source.
674 info modules [-q] [REGEXP]
675 Return a list of Fortran modules matching REGEXP, or all modules if
678 info module functions [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
679 Return a list of functions within all modules, grouped by module.
680 The list of functions can be restricted with the optional regular
681 expressions. MODULE_REGEXP matches against the module name,
682 TYPE_REGEXP matches against the function type signature, and REGEXP
683 matches against the function name.
685 info module variables [-q] [-m MODULE_REGEXP] [-t TYPE_REGEXP] [REGEXP]
686 Return a list of variables within all modules, grouped by module.
687 The list of variables can be restricted with the optional regular
688 expressions. MODULE_REGEXP matches against the module name,
689 TYPE_REGEXP matches against the variable type, and REGEXP matches
690 against the variable name.
692 set debug remote-packet-max-chars
693 show debug remote-packet-max-chars
694 Controls the number of characters to output in a remote packet when using
696 The default is 512 bytes.
699 Lists the target connections currently in use.
704 The "help" command uses the title style to enhance the
705 readibility of its output by styling the classes and
709 Similarly to "help", the "apropos" command also uses the
710 title style for the command names. "apropos" accepts now
711 a flag "-v" (verbose) to show the full documentation
712 of matching commands and to use the highlight style to mark
713 the documentation parts matching REGEXP.
717 The GDB printf and eval commands can now print C-style and Ada-style
718 string convenience variables without calling functions in the program.
719 This allows to do formatted printing of strings without having
720 a running inferior, or when debugging a core dump.
722 info sources [-dirname | -basename] [--] [REGEXP]
723 This command has now optional arguments to only print the files
724 whose names match REGEXP. The arguments -dirname and -basename
725 allow to restrict matching respectively to the dirname and basename
729 The "show style" and its subcommands are now styling
730 a style name in their output using its own style, to help
731 the user visualize the different styles.
733 set print frame-arguments
734 The new value 'presence' indicates to only indicate the presence of
735 arguments using ..., instead of printing argument names and values.
737 set print raw-frame-arguments
738 show print raw-frame-arguments
740 These commands replace the similarly-named "set/show print raw
741 frame-arguments" commands (now with a dash instead of a space). The
742 old commands are now deprecated and may be removed in a future
745 add-inferior [-no-connection]
746 The add-inferior command now supports a "-no-connection" flag that
747 makes the new inferior start with no target connection associated.
748 By default, the new inferior inherits the target connection of the
749 current inferior. See also "info connections".
752 This command's output now includes a new "Connection" column
753 indicating which target connection an inferior is bound to. See
754 "info connections" above.
756 maint test-options require-delimiter
757 maint test-options unknown-is-error
758 maint test-options unknown-is-operand
759 maint show test-options-completion-result
760 Commands used by the testsuite to validate the command options
763 focus, winheight, +, -, >, <
764 These commands are now case-sensitive.
766 * New command options, command completion
768 GDB now has a standard infrastructure to support dash-style command
769 options ('-OPT'). One benefit is that commands that use it can
770 easily support completion of command line arguments. Try "CMD
771 -[TAB]" or "help CMD" to find options supported by a command. Over
772 time, we intend to migrate most commands to this infrastructure. A
773 number of commands got support for new command options in this
776 ** The "print" and "compile print" commands now support a number of
777 options that allow overriding relevant global print settings as
778 set by "set print" subcommands:
782 -array-indexes [on|off]
783 -elements NUMBER|unlimited
788 -repeats NUMBER|unlimited
789 -static-members [on|off]
794 Note that because the "print"/"compile print" commands accept
795 arbitrary expressions which may look like options (including
796 abbreviations), if you specify any command option, then you must
797 use a double dash ("--") to mark the end of argument processing.
799 ** The "backtrace" command now supports a number of options that
800 allow overriding relevant global print settings as set by "set
801 backtrace" and "set print" subcommands:
803 -entry-values no|only|preferred|if-needed|both|compact|default
804 -frame-arguments all|scalars|none
805 -raw-frame-arguments [on|off]
806 -frame-info auto|source-line|location|source-and-location
807 |location-and-address|short-location
811 In addition, the full/no-filters/hide qualifiers are now also
812 exposed as command options too:
818 ** The "frame apply", "tfaas" and "faas" commands similarly now
819 support the following options:
824 ** The new "info sources" options -dirname and -basename options
825 are using the standard '-OPT' infrastructure.
827 All options above can also be abbreviated. The argument of boolean
828 (on/off) options can be 0/1 too, and also the argument is assumed
829 "on" if omitted. This allows writing compact command invocations,
832 (gdb) p -ra -p -o 0 -- *myptr
834 The above is equivalent to:
836 (gdb) print -raw-values -pretty -object off -- *myptr
838 ** The "info types" command now supports the '-q' flag to disable
839 printing of some header information in a similar fashion to "info
840 variables" and "info functions".
842 ** The "info variables", "info functions", and "whereis" commands
843 now take a '-n' flag that excludes non-debug symbols (symbols
844 from the symbol table, not from the debug info such as DWARF)
847 * Completion improvements
849 ** GDB can now complete the options of the "thread apply all" and
850 "taas" commands, and their "-ascending" option can now be
853 ** GDB can now complete the options of the "info threads", "info
854 functions", "info variables", "info locals", and "info args"
857 ** GDB can now complete the options of the "compile file" and
858 "compile code" commands. The "compile file" command now
859 completes on filenames.
861 ** GDB can now complete the backtrace command's
862 "full/no-filters/hide" qualifiers.
864 * In settings, you can now abbreviate "unlimited".
866 E.g., "set print elements u" is now equivalent to "set print
872 This lists all the possible completions for the rest of the line, if it
873 were to be given as a command itself. This is intended for use by MI
874 frontends in cases when separate CLI and MI channels cannot be used.
876 -catch-throw, -catch-rethrow, and -catch-catch
877 These can be used to catch C++ exceptions in a similar fashion to
878 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
880 -symbol-info-functions, -symbol-info-types, and -symbol-info-variables
881 These commands are the MI equivalent of the CLI commands 'info
882 functions', 'info types', and 'info variables' respectively.
884 -symbol-info-modules, this is the MI equivalent of the CLI 'info
887 -symbol-info-module-functions and -symbol-info-module-variables.
888 These commands are the MI equivalent of the CLI commands 'info
889 module functions' and 'info module variables'.
893 ** The default version of the MI interpreter is now 3 (-i=mi3).
895 ** The output of information about multi-location breakpoints (which is
896 syntactically incorrect in MI 2) has changed in MI 3. This affects
897 the following commands and events:
901 - =breakpoint-created
902 - =breakpoint-modified
904 The -fix-multi-location-breakpoint-output command can be used to enable
905 this behavior with previous MI versions.
907 ** Backtraces and frames include a new optional field addr_flags which is
908 given after the addr field. On AArch64 this contains PAC if the address
909 has been masked in the frame. On all other targets the field is not
914 The testsuite now creates the files gdb.cmd (containing the arguments
915 used to launch GDB) and gdb.in (containing all the commands sent to
916 GDB) in the output directory for each test script. Multiple invocations
917 are appended with .1, .2, .3 etc.
919 * Building GDB and GDBserver now requires GNU make >= 3.82.
921 Using another implementation of the make program or an earlier version of
922 GNU make to build GDB or GDBserver is not supported.
924 * Building GDB now requires GNU readline >= 7.0.
926 GDB now bundles GNU readline 8.0, but if you choose to use
927 --with-system-readline, only readline >= 7.0 can be used.
929 * The TUI SingleKey keymap is now named "SingleKey". This can be used
930 from .inputrc to bind keys in this keymap. This feature is only
931 available when gdb is built against GNU readline 8.0 or later.
933 * Removed targets and native configurations
935 GDB no longer supports debugging the Cell Broadband Engine. This includes
936 both debugging standalone Cell/B.E. SPU applications and integrated debugging
937 of Cell/B.E. applications that use both the PPU and SPU architectures.
943 * Removed targets and native configurations
945 Solaris 10 i?86-*-solaris2.10, x86_64-*-solaris2.10,
948 *** Changes in GDB 8.3
950 * GDB and GDBserver now support access to additional registers on
951 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
954 * GDB now has experimental support for the compilation and injection of
955 C++ source code into the inferior. This beta release does not include
956 support for several language features, such as templates, constructors,
959 This feature requires GCC 7.1 or higher built with libcp1.so
962 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
963 can be passed using the '[ADDRESS]:PORT' notation, or the regular
964 'ADDRESS:PORT' method.
966 * DWARF index cache: GDB can now automatically save indices of DWARF
967 symbols on disk to speed up further loading of the same binaries.
969 * Ada task switching is now supported on aarch64-elf targets when
970 debugging a program using the Ravenscar Profile. For more information,
971 see the "Tasking Support when using the Ravenscar Profile" section
972 in the GDB user manual.
974 * GDB in batch mode now exits with status 1 if the last command to be
977 * The RISC-V target now supports target descriptions.
979 * System call catchpoints now support system call aliases on FreeBSD.
980 When the ABI of a system call changes in FreeBSD, this is
981 implemented by leaving a compatibility system call using the old ABI
982 at the existing number and allocating a new system call number for
983 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
984 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
985 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
986 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
987 so that a system call catchpoint for the 'kevent' system call will
988 catch invocations of both the 'kevent' and 'freebsd11_kevent'
989 binaries. This ensures that 'kevent' system calls are caught for
990 binaries using either the old or new ABIs.
992 * Terminal styling is now available for the CLI and the TUI. GNU
993 Source Highlight can additionally be used to provide styling of
994 source code snippets. See the "set style" commands, below, for more
997 * Removed support for old demangling styles arm, edg, gnu, hp and
1002 set debug compile-cplus-types
1003 show debug compile-cplus-types
1004 Control the display of debug output about type conversion in the
1005 C++ compile feature. Commands have no effect while compiling
1006 for other languages.
1010 Control whether debug output about files/functions skipping is
1013 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
1014 Apply a command to some frames.
1015 FLAG arguments allow to control what output to produce and how to handle
1016 errors raised when applying COMMAND to a frame.
1019 Apply a command to all threads (ignoring errors and empty output).
1020 Shortcut for 'thread apply all -s COMMAND'.
1023 Apply a command to all frames (ignoring errors and empty output).
1024 Shortcut for 'frame apply all -s COMMAND'.
1027 Apply a command to all frames of all threads (ignoring errors and empty
1029 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
1031 maint set dwarf unwinders (on|off)
1032 maint show dwarf unwinders
1033 Control whether DWARF unwinders can be used.
1036 Display a list of open files for a process.
1040 Changes to the "frame", "select-frame", and "info frame" CLI commands.
1041 These commands all now take a frame specification which
1042 is either a frame level, or one of the keywords 'level', 'address',
1043 'function', or 'view' followed by a parameter. Selecting a frame by
1044 address, or viewing a frame outside the current backtrace now
1045 requires the use of a keyword. Selecting a frame by level is
1046 unchanged. The MI comment "-stack-select-frame" is unchanged.
1048 target remote FILENAME
1049 target extended-remote FILENAME
1050 If FILENAME is a Unix domain socket, GDB will attempt to connect
1051 to this socket instead of opening FILENAME as a character device.
1053 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
1054 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
1055 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
1056 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
1057 These commands can now print only the searched entities
1058 matching the provided regexp(s), giving a condition
1059 on the entity names or entity types. The flag -q disables
1060 printing headers or informations messages.
1066 These commands now determine the syntax for the shown entities
1067 according to the language chosen by `set language'. In particular,
1068 `set language auto' means to automatically choose the language of
1071 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
1072 The 'thread apply' command accepts new FLAG arguments.
1073 FLAG arguments allow to control what output to produce and how to handle
1074 errors raised when applying COMMAND to a thread.
1076 set tui tab-width NCHARS
1077 show tui tab-width NCHARS
1078 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
1080 set style enabled [on|off]
1082 Enable or disable terminal styling. Styling is enabled by default
1083 on most hosts, but disabled by default when in batch mode.
1085 set style sources [on|off]
1087 Enable or disable source code styling. Source code styling is
1088 enabled by default, but only takes effect if styling in general is
1089 enabled, and if GDB was linked with GNU Source Highlight.
1091 set style filename foreground COLOR
1092 set style filename background COLOR
1093 set style filename intensity VALUE
1094 Control the styling of file names.
1096 set style function foreground COLOR
1097 set style function background COLOR
1098 set style function intensity VALUE
1099 Control the styling of function names.
1101 set style variable foreground COLOR
1102 set style variable background COLOR
1103 set style variable intensity VALUE
1104 Control the styling of variable names.
1106 set style address foreground COLOR
1107 set style address background COLOR
1108 set style address intensity VALUE
1109 Control the styling of addresses.
1113 ** The '-data-disassemble' MI command now accepts an '-a' option to
1114 disassemble the whole function surrounding the given program
1115 counter value or function name. Support for this feature can be
1116 verified by using the "-list-features" command, which should
1117 contain "data-disassemble-a-option".
1119 ** Command responses and notifications that include a frame now include
1120 the frame's architecture in a new "arch" attribute.
1122 * New native configurations
1124 GNU/Linux/RISC-V riscv*-*-linux*
1125 FreeBSD/riscv riscv*-*-freebsd*
1129 GNU/Linux/RISC-V riscv*-*-linux*
1130 CSKY ELF csky*-*-elf
1131 CSKY GNU/LINUX csky*-*-linux
1132 FreeBSD/riscv riscv*-*-freebsd*
1134 GNU/Linux/OpenRISC or1k*-*-linux*
1138 GDB no longer supports native debugging on versions of MS-Windows
1143 ** GDB no longer supports Python versions less than 2.6.
1145 ** The gdb.Inferior type has a new 'progspace' property, which is the program
1146 space associated to that inferior.
1148 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
1149 of objfiles associated to that program space.
1151 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
1152 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
1155 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
1156 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
1157 correct and did not work properly.
1159 ** The gdb.Value type has a new constructor, which is used to construct a
1160 gdb.Value from a Python buffer object and a gdb.Type.
1166 Enable or disable the undefined behavior sanitizer. This is
1167 disabled by default, but passing --enable-ubsan=yes or
1168 --enable-ubsan=auto to configure will enable it. Enabling this can
1169 cause a performance penalty. The undefined behavior sanitizer was
1170 first introduced in GCC 4.9.
1172 *** Changes in GDB 8.2
1174 * The 'set disassembler-options' command now supports specifying options
1175 for the MIPS target.
1177 * The 'symbol-file' command now accepts an '-o' option to add a relative
1178 offset to all sections.
1180 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
1181 a relative offset to all sections, but it allows to override the load
1182 address of individual sections using '-s'.
1184 * The 'add-symbol-file' command no longer requires the second argument
1185 (address of the text section).
1187 * The endianness used with the 'set endian auto' mode in the absence of
1188 an executable selected for debugging is now the last endianness chosen
1189 either by one of the 'set endian big' and 'set endian little' commands
1190 or by inferring from the last executable used, rather than the startup
1193 * The pager now allows a "c" response, meaning to disable the pager
1194 for the rest of the current command.
1196 * The commands 'info variables/functions/types' now show the source line
1197 numbers of symbol definitions when available.
1199 * 'info proc' now works on running processes on FreeBSD systems and core
1200 files created on FreeBSD systems.
1202 * C expressions can now use _Alignof, and C++ expressions can now use
1205 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
1206 the vector length while the process is running.
1212 Control display of debugging info regarding the FreeBSD native target.
1214 set|show varsize-limit
1215 This new setting allows the user to control the maximum size of Ada
1216 objects being printed when those objects have a variable type,
1217 instead of that maximum size being hardcoded to 65536 bytes.
1219 set|show record btrace cpu
1220 Controls the processor to be used for enabling errata workarounds for
1221 branch trace decode.
1223 maint check libthread-db
1224 Run integrity checks on the current inferior's thread debugging
1227 maint set check-libthread-db (on|off)
1228 maint show check-libthread-db
1229 Control whether to run integrity checks on inferior specific thread
1230 debugging libraries as they are loaded. The default is not to
1231 perform such checks.
1235 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
1237 ** The commands attached to a breakpoint can be set by assigning to
1238 the breakpoint's "commands" field.
1240 ** gdb.execute can now execute multi-line gdb commands.
1242 ** The new functions gdb.convenience_variable and
1243 gdb.set_convenience_variable can be used to get and set the value
1244 of convenience variables.
1246 ** A gdb.Parameter will no longer print the "set" help text on an
1247 ordinary "set"; instead by default a "set" will be silent unless
1248 the get_set_string method returns a non-empty string.
1252 RiscV ELF riscv*-*-elf
1254 * Removed targets and native configurations
1256 m88k running OpenBSD m88*-*-openbsd*
1257 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
1258 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
1259 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
1261 * Aarch64/Linux hardware watchpoints improvements
1263 Hardware watchpoints on unaligned addresses are now properly
1264 supported when running Linux kernel 4.10 or higher: read and access
1265 watchpoints are no longer spuriously missed, and all watchpoints
1266 lengths between 1 and 8 bytes are supported. On older kernels,
1267 watchpoints set on unaligned addresses are no longer missed, with
1268 the tradeoff that there is a possibility of false hits being
1273 --enable-codesign=CERT
1274 This can be used to invoke "codesign -s CERT" after building gdb.
1275 This option is useful on macOS, where code signing is required for
1276 gdb to work properly.
1278 --disable-gdbcli has been removed
1279 This is now silently accepted, but does nothing.
1281 *** Changes in GDB 8.1
1283 * GDB now supports dynamically creating arbitrary register groups specified
1284 in XML target descriptions. This allows for finer grain grouping of
1285 registers on systems with a large amount of registers.
1287 * The 'ptype' command now accepts a '/o' flag, which prints the
1288 offsets and sizes of fields in a struct, like the pahole(1) tool.
1290 * New "--readnever" command line option instructs GDB to not read each
1291 symbol file's symbolic debug information. This makes startup faster
1292 but at the expense of not being able to perform symbolic debugging.
1293 This option is intended for use cases where symbolic debugging will
1294 not be used, e.g., when you only need to dump the debuggee's core.
1296 * GDB now uses the GNU MPFR library, if available, to emulate target
1297 floating-point arithmetic during expression evaluation when the target
1298 uses different floating-point formats than the host. At least version
1299 3.1 of GNU MPFR is required.
1301 * GDB now supports access to the guarded-storage-control registers and the
1302 software-based guarded-storage broadcast control registers on IBM z14.
1304 * On Unix systems, GDB now supports transmitting environment variables
1305 that are to be set or unset to GDBserver. These variables will
1306 affect the environment to be passed to the remote inferior.
1308 To inform GDB of environment variables that are to be transmitted to
1309 GDBserver, use the "set environment" command. Only user set
1310 environment variables are sent to GDBserver.
1312 To inform GDB of environment variables that are to be unset before
1313 the remote inferior is started by the GDBserver, use the "unset
1314 environment" command.
1316 * Completion improvements
1318 ** GDB can now complete function parameters in linespecs and
1319 explicit locations without quoting. When setting breakpoints,
1320 quoting around functions names to help with TAB-completion is
1321 generally no longer necessary. For example, this now completes
1324 (gdb) b function(in[TAB]
1325 (gdb) b function(int)
1327 Related, GDB is no longer confused with completing functions in
1328 C++ anonymous namespaces:
1331 (gdb) b (anonymous namespace)::[TAB][TAB]
1332 (anonymous namespace)::a_function()
1333 (anonymous namespace)::b_function()
1335 ** GDB now has much improved linespec and explicit locations TAB
1336 completion support, that better understands what you're
1337 completing and offers better suggestions. For example, GDB no
1338 longer offers data symbols as possible completions when you're
1339 setting a breakpoint.
1341 ** GDB now TAB-completes label symbol names.
1343 ** The "complete" command now mimics TAB completion accurately.
1345 * New command line options (gcore)
1348 Dump all memory mappings.
1350 * Breakpoints on C++ functions are now set on all scopes by default
1352 By default, breakpoints on functions/methods are now interpreted as
1353 specifying all functions with the given name ignoring missing
1354 leading scopes (namespaces and classes).
1356 For example, assuming a C++ program with symbols named:
1361 both commands "break func()" and "break B::func()" set a breakpoint
1364 You can use the new flag "-qualified" to override this. This makes
1365 GDB interpret the specified function name as a complete
1366 fully-qualified name instead. For example, using the same C++
1367 program, the "break -q B::func" command sets a breakpoint on
1368 "B::func", only. A parameter has been added to the Python
1369 gdb.Breakpoint constructor to achieve the same result when creating
1370 a breakpoint from Python.
1372 * Breakpoints on functions marked with C++ ABI tags
1374 GDB can now set breakpoints on functions marked with C++ ABI tags
1375 (e.g., [abi:cxx11]). See here for a description of ABI tags:
1376 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
1378 Functions with a C++11 abi tag are demangled/displayed like this:
1380 function[abi:cxx11](int)
1383 You can now set a breakpoint on such functions simply as if they had
1386 (gdb) b function(int)
1388 Or if you need to disambiguate between tags, like:
1390 (gdb) b function[abi:other_tag](int)
1392 Tab completion was adjusted accordingly as well.
1396 ** New events gdb.new_inferior, gdb.inferior_deleted, and
1397 gdb.new_thread are emitted. See the manual for further
1398 description of these.
1400 ** A new function, "gdb.rbreak" has been added to the Python API.
1401 This function allows the setting of a large number of breakpoints
1402 via a regex pattern in Python. See the manual for further details.
1404 ** Python breakpoints can now accept explicit locations. See the
1405 manual for a further description of this feature.
1408 * New features in the GDB remote stub, GDBserver
1410 ** GDBserver is now able to start inferior processes with a
1411 specified initial working directory.
1413 The user can set the desired working directory to be used from
1414 GDB using the new "set cwd" command.
1416 ** New "--selftest" command line option runs some GDBserver self
1417 tests. These self tests are disabled in releases.
1419 ** On Unix systems, GDBserver now does globbing expansion and variable
1420 substitution in inferior command line arguments.
1422 This is done by starting inferiors using a shell, like GDB does.
1423 See "set startup-with-shell" in the user manual for how to disable
1424 this from GDB when using "target extended-remote". When using
1425 "target remote", you can disable the startup with shell by using the
1426 new "--no-startup-with-shell" GDBserver command line option.
1428 ** On Unix systems, GDBserver now supports receiving environment
1429 variables that are to be set or unset from GDB. These variables
1430 will affect the environment to be passed to the inferior.
1432 * When catching an Ada exception raised with a message, GDB now prints
1433 the message in the catchpoint hit notification. In GDB/MI mode, that
1434 information is provided as an extra field named "exception-message"
1435 in the *stopped notification.
1437 * Trait objects can now be inspected When debugging Rust code. This
1438 requires compiler support which will appear in Rust 1.24.
1440 * New remote packets
1442 QEnvironmentHexEncoded
1443 Inform GDBserver of an environment variable that is to be passed to
1444 the inferior when starting it.
1447 Inform GDBserver of an environment variable that is to be unset
1448 before starting the remote inferior.
1451 Inform GDBserver that the environment should be reset (i.e.,
1452 user-set environment variables should be unset).
1455 Indicates whether the inferior must be started with a shell or not.
1458 Tell GDBserver that the inferior to be started should use a specific
1461 * The "maintenance print c-tdesc" command now takes an optional
1462 argument which is the file name of XML target description.
1464 * The "maintenance selftest" command now takes an optional argument to
1465 filter the tests to be run.
1467 * The "enable", and "disable" commands now accept a range of
1468 breakpoint locations, e.g. "enable 1.3-5".
1473 Set and show the current working directory for the inferior.
1475 set|show compile-gcc
1476 Set and show compilation command used for compiling and injecting code
1477 with the 'compile' commands.
1479 set debug separate-debug-file
1480 show debug separate-debug-file
1481 Control the display of debug output about separate debug file search.
1483 set dump-excluded-mappings
1484 show dump-excluded-mappings
1485 Control whether mappings marked with the VM_DONTDUMP flag should be
1486 dumped when generating a core file.
1488 maint info selftests
1489 List the registered selftests.
1492 Start the debugged program stopping at the first instruction.
1495 Control display of debugging messages related to OpenRISC targets.
1497 set|show print type nested-type-limit
1498 Set and show the limit of nesting level for nested types that the
1499 type printer will show.
1501 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
1504 * Safer/improved support for debugging with no debug info
1506 GDB no longer assumes functions with no debug information return
1509 This means that GDB now refuses to call such functions unless you
1510 tell it the function's type, by either casting the call to the
1511 declared return type, or by casting the function to a function
1512 pointer of the right type, and calling that:
1514 (gdb) p getenv ("PATH")
1515 'getenv' has unknown return type; cast the call to its declared return type
1516 (gdb) p (char *) getenv ("PATH")
1517 $1 = 0x7fffffffe "/usr/local/bin:/"...
1518 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
1519 $2 = 0x7fffffffe "/usr/local/bin:/"...
1521 Similarly, GDB no longer assumes that global variables with no debug
1522 info have type 'int', and refuses to print the variable's value
1523 unless you tell it the variable's type:
1526 'var' has unknown type; cast it to its declared type
1530 * New native configurations
1532 FreeBSD/aarch64 aarch64*-*-freebsd*
1533 FreeBSD/arm arm*-*-freebsd*
1537 FreeBSD/aarch64 aarch64*-*-freebsd*
1538 FreeBSD/arm arm*-*-freebsd*
1539 OpenRISC ELF or1k*-*-elf
1541 * Removed targets and native configurations
1543 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
1545 *** Changes in GDB 8.0
1547 * GDB now supports access to the PKU register on GNU/Linux. The register is
1548 added by the Memory Protection Keys for Userspace feature which will be
1549 available in future Intel CPUs.
1551 * GDB now supports C++11 rvalue references.
1555 ** New functions to start, stop and access a running btrace recording.
1556 ** Rvalue references are now supported in gdb.Type.
1558 * GDB now supports recording and replaying rdrand and rdseed Intel 64
1561 * Building GDB and GDBserver now requires a C++11 compiler.
1563 For example, GCC 4.8 or later.
1565 It is no longer possible to build GDB or GDBserver with a C
1566 compiler. The --disable-build-with-cxx configure option has been
1569 * Building GDB and GDBserver now requires GNU make >= 3.81.
1571 It is no longer supported to build GDB or GDBserver with another
1572 implementation of the make program or an earlier version of GNU make.
1574 * Native debugging on MS-Windows supports command-line redirection
1576 Command-line arguments used for starting programs on MS-Windows can
1577 now include redirection symbols supported by native Windows shells,
1578 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
1579 as "run", "start", and "set args", as well as the corresponding MI
1582 * Support for thread names on MS-Windows.
1584 GDB now catches and handles the special exception that programs
1585 running on MS-Windows use to assign names to threads in the
1588 * Support for Java programs compiled with gcj has been removed.
1590 * User commands now accept an unlimited number of arguments.
1591 Previously, only up to 10 was accepted.
1593 * The "eval" command now expands user-defined command arguments.
1595 This makes it easier to process a variable number of arguments:
1600 eval "print $arg%d", $i
1605 * Target descriptions can now describe registers for sparc32 and sparc64.
1607 * GDB now supports DWARF version 5 (debug information format).
1608 Its .debug_names index is not yet supported.
1610 * New native configurations
1612 FreeBSD/mips mips*-*-freebsd
1616 Synopsys ARC arc*-*-elf32
1617 FreeBSD/mips mips*-*-freebsd
1619 * Removed targets and native configurations
1621 Alpha running FreeBSD alpha*-*-freebsd*
1622 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
1627 Erases all the flash memory regions reported by the target.
1629 maint print arc arc-instruction address
1630 Print internal disassembler information about instruction at a given address.
1634 set disassembler-options
1635 show disassembler-options
1636 Controls the passing of target specific information to the disassembler.
1637 If it is necessary to specify more than one disassembler option then
1638 multiple options can be placed together into a comma separated list.
1639 The default value is the empty string. Currently, the only supported
1640 targets are ARM, PowerPC and S/390.
1645 Erases all the flash memory regions reported by the target. This is
1646 equivalent to the CLI command flash-erase.
1648 -file-list-shared-libraries
1649 List the shared libraries in the program. This is
1650 equivalent to the CLI command "info shared".
1653 Catchpoints stopping the program when Ada exceptions are
1654 handled. This is equivalent to the CLI command "catch handlers".
1656 *** Changes in GDB 7.12
1658 * GDB and GDBserver now build with a C++ compiler by default.
1660 The --enable-build-with-cxx configure option is now enabled by
1661 default. One must now explicitly configure with
1662 --disable-build-with-cxx in order to build with a C compiler. This
1663 option will be removed in a future release.
1665 * GDBserver now supports recording btrace without maintaining an active
1668 * GDB now supports a negative repeat count in the 'x' command to examine
1669 memory backward from the given address. For example:
1672 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
1673 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
1674 (gdb) x/-5i 0x0000000000400580
1675 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
1676 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
1677 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
1678 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
1679 0x40057b <main(int, char**)+25>:
1680 callq 0x400536 <Func1(int, char const*)>
1682 * Fortran: Support structures with fields of dynamic types and
1683 arrays of dynamic types.
1685 * The symbol dumping maintenance commands have new syntax.
1686 maint print symbols [-pc address] [--] [filename]
1687 maint print symbols [-objfile objfile] [-source source] [--] [filename]
1688 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
1689 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
1690 maint print msymbols [-objfile objfile] [--] [filename]
1692 * GDB now supports multibit bitfields and enums in target register
1695 * New Python-based convenience function $_as_string(val), which returns
1696 the textual representation of a value. This function is especially
1697 useful to obtain the text label of an enum value.
1699 * Intel MPX bound violation handling.
1701 Segmentation faults caused by a Intel MPX boundary violation
1702 now display the kind of violation (upper or lower), the memory
1703 address accessed and the memory bounds, along with the usual
1704 signal received and code location.
1708 Program received signal SIGSEGV, Segmentation fault
1709 Upper bound violation while accessing address 0x7fffffffc3b3
1710 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
1711 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
1713 * Rust language support.
1714 GDB now supports debugging programs written in the Rust programming
1715 language. See https://www.rust-lang.org/ for more information about
1718 * Support for running interpreters on specified input/output devices
1720 GDB now supports a new mechanism that allows frontends to provide
1721 fully featured GDB console views, as a better alternative to
1722 building such views on top of the "-interpreter-exec console"
1723 command. See the new "new-ui" command below. With that command,
1724 frontends can now start GDB in the traditional command-line mode
1725 running in an embedded terminal emulator widget, and create a
1726 separate MI interpreter running on a specified i/o device. In this
1727 way, GDB handles line editing, history, tab completion, etc. in the
1728 console all by itself, and the GUI uses the separate MI interpreter
1729 for its own control and synchronization, invisible to the command
1732 * The "catch syscall" command catches groups of related syscalls.
1734 The "catch syscall" command now supports catching a group of related
1735 syscalls using the 'group:' or 'g:' prefix.
1740 skip -gfile file-glob-pattern
1741 skip -function function
1742 skip -rfunction regular-expression
1743 A generalized form of the skip command, with new support for
1744 glob-style file names and regular expressions for function names.
1745 Additionally, a file spec and a function spec may now be combined.
1747 maint info line-table REGEXP
1748 Display the contents of GDB's internal line table data structure.
1751 Run any GDB unit tests that were compiled in.
1754 Start a new user interface instance running INTERP as interpreter,
1755 using the TTY file for input/output.
1759 ** gdb.Breakpoint objects have a new attribute "pending", which
1760 indicates whether the breakpoint is pending.
1761 ** Three new breakpoint-related events have been added:
1762 gdb.breakpoint_created, gdb.breakpoint_modified, and
1763 gdb.breakpoint_deleted.
1765 signal-event EVENTID
1766 Signal ("set") the given MS-Windows event object. This is used in
1767 conjunction with the Windows JIT debugging (AeDebug) support, where
1768 the OS suspends a crashing process until a debugger can attach to
1769 it. Resuming the crashing process, in order to debug it, is done by
1770 signalling an event.
1772 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
1773 was added in GDBserver, including JIT compiling fast tracepoint's
1774 conditional expression bytecode into native code.
1776 * Support for various remote target protocols and ROM monitors has
1779 target m32rsdi Remote M32R debugging over SDI
1780 target mips MIPS remote debugging protocol
1781 target pmon PMON ROM monitor
1782 target ddb NEC's DDB variant of PMON for Vr4300
1783 target rockhopper NEC RockHopper variant of PMON
1784 target lsi LSI variant of PMO
1786 * Support for tracepoints and fast tracepoints on powerpc-linux,
1787 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
1788 including JIT compiling fast tracepoint's conditional expression
1789 bytecode into native code.
1791 * MI async record =record-started now includes the method and format used for
1792 recording. For example:
1794 =record-started,thread-group="i1",method="btrace",format="bts"
1796 * MI async record =thread-selected now includes the frame field. For example:
1798 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
1802 Andes NDS32 nds32*-*-elf
1804 *** Changes in GDB 7.11
1806 * GDB now supports debugging kernel-based threads on FreeBSD.
1808 * Per-inferior thread numbers
1810 Thread numbers are now per inferior instead of global. If you're
1811 debugging multiple inferiors, GDB displays thread IDs using a
1812 qualified INF_NUM.THR_NUM form. For example:
1816 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
1817 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1818 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1819 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1821 As consequence, thread numbers as visible in the $_thread
1822 convenience variable and in Python's InferiorThread.num attribute
1823 are no longer unique between inferiors.
1825 GDB now maintains a second thread ID per thread, referred to as the
1826 global thread ID, which is the new equivalent of thread numbers in
1827 previous releases. See also $_gthread below.
1829 For backwards compatibility, MI's thread IDs always refer to global
1832 * Commands that accept thread IDs now accept the qualified
1833 INF_NUM.THR_NUM form as well. For example:
1836 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1839 * In commands that accept a list of thread IDs, you can now refer to
1840 all threads of an inferior using a star wildcard. GDB accepts
1841 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1842 refer to all threads of the current inferior. For example, "info
1845 * You can use "info threads -gid" to display the global thread ID of
1848 * The new convenience variable $_gthread holds the global number of
1851 * The new convenience variable $_inferior holds the number of the
1854 * GDB now displays the ID and name of the thread that hit a breakpoint
1855 or received a signal, if your program is multi-threaded. For
1858 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1859 Thread 1 "main" received signal SIGINT, Interrupt.
1861 * Record btrace now supports non-stop mode.
1863 * Support for tracepoints on aarch64-linux was added in GDBserver.
1865 * The 'record instruction-history' command now indicates speculative execution
1866 when using the Intel Processor Trace recording format.
1868 * GDB now allows users to specify explicit locations, bypassing
1869 the linespec parser. This feature is also available to GDB/MI
1872 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1873 GDB now is able to debug both AArch64 applications and ARM applications
1876 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1877 including JIT compiling fast tracepoint's conditional expression bytecode
1880 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1882 * "info threads", "info inferiors", "info display", "info checkpoints"
1883 and "maint info program-spaces" now list the corresponding items in
1884 ascending ID order, for consistency with all other "info" commands.
1886 * In Ada, the overloads selection menu has been enhanced to display the
1887 parameter types and the return types for the matching overloaded subprograms.
1891 maint set target-non-stop (on|off|auto)
1892 maint show target-non-stop
1893 Control whether GDB targets always operate in non-stop mode even if
1894 "set non-stop" is "off". The default is "auto", meaning non-stop
1895 mode is enabled if supported by the target.
1897 maint set bfd-sharing
1898 maint show bfd-sharing
1899 Control the reuse of bfd objects.
1902 show debug bfd-cache
1903 Control display of debugging info regarding bfd caching.
1907 Control display of debugging info regarding FreeBSD threads.
1909 set remote multiprocess-extensions-packet
1910 show remote multiprocess-extensions-packet
1911 Set/show the use of the remote protocol multiprocess extensions.
1913 set remote thread-events
1914 show remote thread-events
1915 Set/show the use of thread create/exit events.
1917 set ada print-signatures on|off
1918 show ada print-signatures"
1919 Control whether parameter types and return types are displayed in overloads
1920 selection menus. It is activated (@code{on}) by default.
1924 Controls the maximum size of memory, in bytes, that GDB will
1925 allocate for value contents. Prevents incorrect programs from
1926 causing GDB to allocate overly large buffers. Default is 64k.
1928 * The "disassemble" command accepts a new modifier: /s.
1929 It prints mixed source+disassembly like /m with two differences:
1930 - disassembled instructions are now printed in program order, and
1931 - and source for all relevant files is now printed.
1932 The "/m" option is now considered deprecated: its "source-centric"
1933 output hasn't proved useful in practice.
1935 * The "record instruction-history" command accepts a new modifier: /s.
1936 It behaves exactly like /m and prints mixed source+disassembly.
1938 * The "set scheduler-locking" command supports a new mode "replay".
1939 It behaves like "off" in record mode and like "on" in replay mode.
1941 * Support for various ROM monitors has been removed:
1943 target dbug dBUG ROM monitor for Motorola ColdFire
1944 target picobug Motorola picobug monitor
1945 target dink32 DINK32 ROM monitor for PowerPC
1946 target m32r Renesas M32R/D ROM monitor
1947 target mon2000 mon2000 ROM monitor
1948 target ppcbug PPCBUG ROM monitor for PowerPC
1950 * Support for reading/writing memory and extracting values on architectures
1951 whose memory is addressable in units of any integral multiple of 8 bits.
1954 Allows to break when an Ada exception is handled.
1956 * New remote packets
1959 Indicates that an exec system call was executed.
1961 exec-events feature in qSupported
1962 The qSupported packet allows GDB to request support for exec
1963 events using the new 'gdbfeature' exec-event, and the qSupported
1964 response can contain the corresponding 'stubfeature'. Set and
1965 show commands can be used to display whether these features are enabled.
1968 Equivalent to interrupting with the ^C character, but works in
1971 thread created stop reason (T05 create:...)
1972 Indicates that the thread was just created and is stopped at entry.
1974 thread exit stop reply (w exitcode;tid)
1975 Indicates that the thread has terminated.
1978 Enables/disables thread create and exit event reporting. For
1979 example, this is used in non-stop mode when GDB stops a set of
1980 threads and synchronously waits for the their corresponding stop
1981 replies. Without exit events, if one of the threads exits, GDB
1982 would hang forever not knowing that it should no longer expect a
1983 stop for that same thread.
1986 Indicates that there are no resumed threads left in the target (all
1987 threads are stopped). The remote stub reports support for this stop
1988 reply to GDB's qSupported query.
1991 Enables/disables catching syscalls from the inferior process.
1992 The remote stub reports support for this packet to GDB's qSupported query.
1994 syscall_entry stop reason
1995 Indicates that a syscall was just called.
1997 syscall_return stop reason
1998 Indicates that a syscall just returned.
2000 * Extended-remote exec events
2002 ** GDB now has support for exec events on extended-remote Linux targets.
2003 For such targets with Linux kernels 2.5.46 and later, this enables
2004 follow-exec-mode and exec catchpoints.
2006 set remote exec-event-feature-packet
2007 show remote exec-event-feature-packet
2008 Set/show the use of the remote exec event feature.
2010 * Thread names in remote protocol
2012 The reply to qXfer:threads:read may now include a name attribute for each
2015 * Target remote mode fork and exec events
2017 ** GDB now has support for fork and exec events on target remote mode
2018 Linux targets. For such targets with Linux kernels 2.5.46 and later,
2019 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
2020 fork and exec catchpoints.
2022 * Remote syscall events
2024 ** GDB now has support for catch syscall on remote Linux targets,
2025 currently enabled on x86/x86_64 architectures.
2027 set remote catch-syscall-packet
2028 show remote catch-syscall-packet
2029 Set/show the use of the remote catch syscall feature.
2033 ** The -var-set-format command now accepts the zero-hexadecimal
2034 format. It outputs data in hexadecimal format with zero-padding on the
2039 ** gdb.InferiorThread objects have a new attribute "global_num",
2040 which refers to the thread's global thread ID. The existing
2041 "num" attribute now refers to the thread's per-inferior number.
2042 See "Per-inferior thread numbers" above.
2043 ** gdb.InferiorThread objects have a new attribute "inferior", which
2044 is the Inferior object the thread belongs to.
2046 *** Changes in GDB 7.10
2048 * Support for process record-replay and reverse debugging on aarch64*-linux*
2049 targets has been added. GDB now supports recording of A64 instruction set
2050 including advance SIMD instructions.
2052 * Support for Sun's version of the "stabs" debug file format has been removed.
2054 * GDB now honors the content of the file /proc/PID/coredump_filter
2055 (PID is the process ID) on GNU/Linux systems. This file can be used
2056 to specify the types of memory mappings that will be included in a
2057 corefile. For more information, please refer to the manual page of
2058 "core(5)". GDB also has a new command: "set use-coredump-filter
2059 on|off". It allows to set whether GDB will read the content of the
2060 /proc/PID/coredump_filter file when generating a corefile.
2062 * The "info os" command on GNU/Linux can now display information on
2064 "info os cpus" Listing of all cpus/cores on the system
2066 * GDB has two new commands: "set serial parity odd|even|none" and
2067 "show serial parity". These allows to set or show parity for the
2070 * The "info source" command now displays the producer string if it was
2071 present in the debug info. This typically includes the compiler version
2072 and may include things like its command line arguments.
2074 * The "info dll", an alias of the "info sharedlibrary" command,
2075 is now available on all platforms.
2077 * Directory names supplied to the "set sysroot" commands may be
2078 prefixed with "target:" to tell GDB to access shared libraries from
2079 the target system, be it local or remote. This replaces the prefix
2080 "remote:". The default sysroot has been changed from "" to
2081 "target:". "remote:" is automatically converted to "target:" for
2082 backward compatibility.
2084 * The system root specified by "set sysroot" will be prepended to the
2085 filename of the main executable (if reported to GDB as absolute by
2086 the operating system) when starting processes remotely, and when
2087 attaching to already-running local or remote processes.
2089 * GDB now supports automatic location and retrieval of executable
2090 files from remote targets. Remote debugging can now be initiated
2091 using only a "target remote" or "target extended-remote" command
2092 (no "set sysroot" or "file" commands are required). See "New remote
2095 * The "dump" command now supports verilog hex format.
2097 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
2099 * On GNU/Linux, GDB and gdbserver are now able to access executable
2100 and shared library files without a "set sysroot" command when
2101 attaching to processes running in different mount namespaces from
2102 the debugger. This makes it possible to attach to processes in
2103 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
2104 See "New remote packets" below.
2106 * The "tui reg" command now provides completion for all of the
2107 available register groups, including target specific groups.
2109 * The HISTSIZE environment variable is no longer read when determining
2110 the size of GDB's command history. GDB now instead reads the dedicated
2111 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
2112 disables truncation of command history. Non-numeric values of GDBHISTSIZE
2117 ** Memory ports can now be unbuffered.
2121 ** gdb.Objfile objects have a new attribute "username",
2122 which is the name of the objfile as specified by the user,
2123 without, for example, resolving symlinks.
2124 ** You can now write frame unwinders in Python.
2125 ** gdb.Type objects have a new method "optimized_out",
2126 returning optimized out gdb.Value instance of this type.
2127 ** gdb.Value objects have new methods "reference_value" and
2128 "const_value" which return a reference to the value and a
2129 "const" version of the value respectively.
2133 maint print symbol-cache
2134 Print the contents of the symbol cache.
2136 maint print symbol-cache-statistics
2137 Print statistics of symbol cache usage.
2139 maint flush-symbol-cache
2140 Flush the contents of the symbol cache.
2144 Start branch trace recording using Branch Trace Store (BTS) format.
2147 Evaluate expression by using the compiler and print result.
2151 Explicit commands for enabling and disabling tui mode.
2154 set mpx bound on i386 and amd64
2155 Support for bound table investigation on Intel MPX enabled applications.
2159 Start branch trace recording using Intel Processor Trace format.
2162 Print information about branch tracing internals.
2164 maint btrace packet-history
2165 Print the raw branch tracing data.
2167 maint btrace clear-packet-history
2168 Discard the stored raw branch tracing data.
2171 Discard all branch tracing data. It will be fetched and processed
2172 anew by the next "record" command.
2177 Renamed from "set debug dwarf2-die".
2178 show debug dwarf-die
2179 Renamed from "show debug dwarf2-die".
2181 set debug dwarf-read
2182 Renamed from "set debug dwarf2-read".
2183 show debug dwarf-read
2184 Renamed from "show debug dwarf2-read".
2186 maint set dwarf always-disassemble
2187 Renamed from "maint set dwarf2 always-disassemble".
2188 maint show dwarf always-disassemble
2189 Renamed from "maint show dwarf2 always-disassemble".
2191 maint set dwarf max-cache-age
2192 Renamed from "maint set dwarf2 max-cache-age".
2193 maint show dwarf max-cache-age
2194 Renamed from "maint show dwarf2 max-cache-age".
2196 set debug dwarf-line
2197 show debug dwarf-line
2198 Control display of debugging info regarding DWARF line processing.
2201 show max-completions
2202 Set the maximum number of candidates to be considered during
2203 completion. The default value is 200. This limit allows GDB
2204 to avoid generating large completion lists, the computation of
2205 which can cause the debugger to become temporarily unresponsive.
2207 set history remove-duplicates
2208 show history remove-duplicates
2209 Control the removal of duplicate history entries.
2211 maint set symbol-cache-size
2212 maint show symbol-cache-size
2213 Control the size of the symbol cache.
2215 set|show record btrace bts buffer-size
2216 Set and show the size of the ring buffer used for branch tracing in
2218 The obtained size may differ from the requested size. Use "info
2219 record" to see the obtained buffer size.
2221 set debug linux-namespaces
2222 show debug linux-namespaces
2223 Control display of debugging info regarding Linux namespaces.
2225 set|show record btrace pt buffer-size
2226 Set and show the size of the ring buffer used for branch tracing in
2227 Intel Processor Trace format.
2228 The obtained size may differ from the requested size. Use "info
2229 record" to see the obtained buffer size.
2231 maint set|show btrace pt skip-pad
2232 Set and show whether PAD packets are skipped when computing the
2235 * The command 'thread apply all' can now support new option '-ascending'
2236 to call its specified command for all threads in ascending order.
2238 * Python/Guile scripting
2240 ** GDB now supports auto-loading of Python/Guile scripts contained in the
2241 special section named `.debug_gdb_scripts'.
2243 * New remote packets
2245 qXfer:btrace-conf:read
2246 Return the branch trace configuration for the current thread.
2248 Qbtrace-conf:bts:size
2249 Set the requested ring buffer size for branch tracing in BTS format.
2252 Enable Intel Processor Trace-based branch tracing for the current
2253 process. The remote stub reports support for this packet to GDB's
2256 Qbtrace-conf:pt:size
2257 Set the requested ring buffer size for branch tracing in Intel Processor
2261 Indicates a memory breakpoint instruction was executed, irrespective
2262 of whether it was GDB that planted the breakpoint or the breakpoint
2263 is hardcoded in the program. This is required for correct non-stop
2267 Indicates the target stopped for a hardware breakpoint. This is
2268 required for correct non-stop mode operation.
2271 Return information about files on the remote system.
2273 qXfer:exec-file:read
2274 Return the full absolute name of the file that was executed to
2275 create a process running on the remote system.
2278 Select the filesystem on which vFile: operations with filename
2279 arguments will operate. This is required for GDB to be able to
2280 access files on remote targets where the remote stub does not
2281 share a common filesystem with the inferior(s).
2284 Indicates that a fork system call was executed.
2287 Indicates that a vfork system call was executed.
2289 vforkdone stop reason
2290 Indicates that a vfork child of the specified process has executed
2291 an exec or exit, allowing the vfork parent to resume execution.
2293 fork-events and vfork-events features in qSupported
2294 The qSupported packet allows GDB to request support for fork and
2295 vfork events using new 'gdbfeatures' fork-events and vfork-events,
2296 and the qSupported response can contain the corresponding
2297 'stubfeatures'. Set and show commands can be used to display
2298 whether these features are enabled.
2300 * Extended-remote fork events
2302 ** GDB now has support for fork events on extended-remote Linux
2303 targets. For targets with Linux kernels 2.5.60 and later, this
2304 enables follow-fork-mode and detach-on-fork for both fork and
2305 vfork, as well as fork and vfork catchpoints.
2307 * The info record command now shows the recording format and the
2308 branch tracing configuration for the current thread when using
2309 the btrace record target.
2310 For the BTS format, it shows the ring buffer size.
2312 * GDB now has support for DTrace USDT (Userland Static Defined
2313 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
2315 * GDB now supports access to vector registers on S/390 GNU/Linux
2318 * Removed command line options
2320 -xdb HP-UX XDB compatibility mode.
2322 * Removed targets and native configurations
2324 HP/PA running HP-UX hppa*-*-hpux*
2325 Itanium running HP-UX ia64-*-hpux*
2327 * New configure options
2330 This configure option allows the user to build GDB with support for
2331 Intel Processor Trace (default: auto). This requires libipt.
2333 --with-libipt-prefix=PATH
2334 Specify the path to the version of libipt that GDB should use.
2335 $PATH/include should contain the intel-pt.h header and
2336 $PATH/lib should contain the libipt.so library.
2338 *** Changes in GDB 7.9.1
2342 ** Xmethods can now specify a result type.
2344 *** Changes in GDB 7.9
2346 * GDB now supports hardware watchpoints on x86 GNU Hurd.
2350 ** You can now access frame registers from Python scripts.
2351 ** New attribute 'producer' for gdb.Symtab objects.
2352 ** gdb.Objfile objects have a new attribute "progspace",
2353 which is the gdb.Progspace object of the containing program space.
2354 ** gdb.Objfile objects have a new attribute "owner".
2355 ** gdb.Objfile objects have a new attribute "build_id",
2356 which is the build ID generated when the file was built.
2357 ** gdb.Objfile objects have a new method "add_separate_debug_file".
2358 ** A new event "gdb.clear_objfiles" has been added, triggered when
2359 selecting a new file to debug.
2360 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
2361 ** New function gdb.lookup_objfile.
2363 New events which are triggered when GDB modifies the state of the
2366 ** gdb.events.inferior_call_pre: Function call is about to be made.
2367 ** gdb.events.inferior_call_post: Function call has just been made.
2368 ** gdb.events.memory_changed: A memory location has been altered.
2369 ** gdb.events.register_changed: A register has been altered.
2371 * New Python-based convenience functions:
2373 ** $_caller_is(name [, number_of_frames])
2374 ** $_caller_matches(regexp [, number_of_frames])
2375 ** $_any_caller_is(name [, number_of_frames])
2376 ** $_any_caller_matches(regexp [, number_of_frames])
2378 * GDB now supports the compilation and injection of source code into
2379 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
2380 to compile the source code to object code, and if successful, inject
2381 and execute that code within the current context of the inferior.
2382 Currently the C language is supported. The commands used to
2383 interface with this new feature are:
2385 compile code [-raw|-r] [--] [source code]
2386 compile file [-raw|-r] filename
2390 demangle [-l language] [--] name
2391 Demangle "name" in the specified language, or the current language
2392 if elided. This command is renamed from the "maint demangle" command.
2393 The latter is kept as a no-op to avoid "maint demangle" being interpreted
2394 as "maint demangler-warning".
2396 queue-signal signal-name-or-number
2397 Queue a signal to be delivered to the thread when it is resumed.
2399 add-auto-load-scripts-directory directory
2400 Add entries to the list of directories from which to load auto-loaded
2403 maint print user-registers
2404 List all currently available "user" registers.
2406 compile code [-r|-raw] [--] [source code]
2407 Compile, inject, and execute in the inferior the executable object
2408 code produced by compiling the provided source code.
2410 compile file [-r|-raw] filename
2411 Compile and inject into the inferior the executable object code
2412 produced by compiling the source code stored in the filename
2415 * On resume, GDB now always passes the signal the program had stopped
2416 for to the thread the signal was sent to, even if the user changed
2417 threads before resuming. Previously GDB would often (but not
2418 always) deliver the signal to the thread that happens to be current
2421 * Conversely, the "signal" command now consistently delivers the
2422 requested signal to the current thread. GDB now asks for
2423 confirmation if the program had stopped for a signal and the user
2424 switched threads meanwhile.
2426 * "breakpoint always-inserted" modes "off" and "auto" merged.
2428 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
2429 won't remove breakpoints from the target until all threads stop,
2430 even in non-stop mode. The "auto" mode has been removed, and "off"
2431 is now the default mode.
2435 set debug symbol-lookup
2436 show debug symbol-lookup
2437 Control display of debugging info regarding symbol lookup.
2441 ** The -list-thread-groups command outputs an exit-code field for
2442 inferiors that have exited.
2446 MIPS SDE mips*-sde*-elf*
2450 Support for these obsolete configurations has been removed.
2452 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
2453 SGI Irix-5.x mips-*-irix5*
2454 SGI Irix-6.x mips-*-irix6*
2455 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
2456 VAX running Ultrix vax-*-ultrix*
2458 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2459 and "assf"), have been removed. Use the "sharedlibrary" command, or
2460 its alias "share", instead.
2462 *** Changes in GDB 7.8
2464 * New command line options
2467 This is an alias for the --data-directory option.
2469 * GDB supports printing and modifying of variable length automatic arrays
2470 as specified in ISO C99.
2472 * The ARM simulator now supports instruction level tracing
2473 with or without disassembly.
2477 GDB now has support for scripting using Guile. Whether this is
2478 available is determined at configure time.
2479 Guile version 2.0 or greater is required.
2480 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
2482 * New commands (for set/show, see "New options" below)
2486 Invoke CODE by passing it to the Guile interpreter.
2490 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
2492 info auto-load guile-scripts [regexp]
2493 Print the list of automatically loaded Guile scripts.
2495 * The source command is now capable of sourcing Guile scripts.
2496 This feature is dependent on the debugger being built with Guile support.
2500 set print symbol-loading (off|brief|full)
2501 show print symbol-loading
2502 Control whether to print informational messages when loading symbol
2503 information for a file. The default is "full", but when debugging
2504 programs with large numbers of shared libraries the amount of output
2505 becomes less useful.
2507 set guile print-stack (none|message|full)
2508 show guile print-stack
2509 Show a stack trace when an error is encountered in a Guile script.
2511 set auto-load guile-scripts (on|off)
2512 show auto-load guile-scripts
2513 Control auto-loading of Guile script files.
2515 maint ada set ignore-descriptive-types (on|off)
2516 maint ada show ignore-descriptive-types
2517 Control whether the debugger should ignore descriptive types in Ada
2518 programs. The default is not to ignore the descriptive types. See
2519 the user manual for more details on descriptive types and the intended
2520 usage of this option.
2522 set auto-connect-native-target
2524 Control whether GDB is allowed to automatically connect to the
2525 native target for the run, attach, etc. commands when not connected
2526 to any target yet. See also "target native" below.
2528 set record btrace replay-memory-access (read-only|read-write)
2529 show record btrace replay-memory-access
2530 Control what memory accesses are allowed during replay.
2532 maint set target-async (on|off)
2533 maint show target-async
2534 This controls whether GDB targets operate in synchronous or
2535 asynchronous mode. Normally the default is asynchronous, if it is
2536 available; but this can be changed to more easily debug problems
2537 occurring only in synchronous mode.
2539 set mi-async (on|off)
2541 Control whether MI asynchronous mode is preferred. This supersedes
2542 "set target-async" of previous GDB versions.
2544 * "set target-async" is deprecated as a CLI option and is now an alias
2545 for "set mi-async" (only puts MI into async mode).
2547 * Background execution commands (e.g., "c&", "s&", etc.) are now
2548 possible ``out of the box'' if the target supports them. Previously
2549 the user would need to explicitly enable the possibility with the
2550 "set target-async on" command.
2552 * New features in the GDB remote stub, GDBserver
2554 ** New option --debug-format=option1[,option2,...] allows one to add
2555 additional text to each output. At present only timestamps
2556 are supported: --debug-format=timestamps.
2557 Timestamps can also be turned on with the
2558 "monitor set debug-format timestamps" command from GDB.
2560 * The 'record instruction-history' command now starts counting instructions
2561 at one. This also affects the instruction ranges reported by the
2562 'record function-call-history' command when given the /i modifier.
2564 * The command 'record function-call-history' supports a new modifier '/c' to
2565 indent the function names based on their call stack depth.
2566 The fields for the '/i' and '/l' modifier have been reordered.
2567 The source line range is now prefixed with 'at'.
2568 The instruction range is now prefixed with 'inst'.
2569 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
2570 "record instruction-history" and "list" commands.
2572 * The ranges given as arguments to the 'record function-call-history' and
2573 'record instruction-history' commands are now inclusive.
2575 * The btrace record target now supports the 'record goto' command.
2576 For locations inside the execution trace, the back trace is computed
2577 based on the information stored in the execution trace.
2579 * The btrace record target supports limited reverse execution and replay.
2580 The target does not record data and therefore does not allow reading
2581 memory or registers.
2583 * The "catch syscall" command now works on s390*-linux* targets.
2585 * The "compare-sections" command is no longer specific to target
2586 remote. It now works with all targets.
2588 * All native targets are now consistently called "native".
2589 Consequently, the "target child", "target GNU", "target djgpp",
2590 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
2591 commands have been replaced with "target native". The QNX/NTO port
2592 leaves the "procfs" target in place and adds a "native" target for
2593 consistency with other ports. The impact on users should be minimal
2594 as these commands previously either throwed an error, or were
2595 no-ops. The target's name is visible in the output of the following
2596 commands: "help target", "info target", "info files", "maint print
2599 * The "target native" command now connects to the native target. This
2600 can be used to launch native programs even when "set
2601 auto-connect-native-target" is set to off.
2603 * GDB now supports access to Intel MPX registers on GNU/Linux.
2605 * Support for Intel AVX-512 registers on GNU/Linux.
2606 Support displaying and modifying Intel AVX-512 registers
2607 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
2609 * New remote packets
2611 qXfer:btrace:read's annex
2612 The qXfer:btrace:read packet supports a new annex 'delta' to read
2613 branch trace incrementally.
2617 ** Valid Python operations on gdb.Value objects representing
2618 structs/classes invoke the corresponding overloaded operators if
2620 ** New `Xmethods' feature in the Python API. Xmethods are
2621 additional methods or replacements for existing methods of a C++
2622 class. This feature is useful for those cases where a method
2623 defined in C++ source code could be inlined or optimized out by
2624 the compiler, making it unavailable to GDB.
2627 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
2629 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2630 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
2631 its alias "share", instead.
2633 * The commands "set remotebaud" and "show remotebaud" are no longer
2634 supported. Use "set serial baud" and "show serial baud" (respectively)
2639 ** A new option "-gdb-set mi-async" replaces "-gdb-set
2640 target-async". The latter is left as a deprecated alias of the
2641 former for backward compatibility. If the target supports it,
2642 CLI background execution commands are now always possible by
2643 default, independently of whether the frontend stated a
2644 preference for asynchronous execution with "-gdb-set mi-async".
2645 Previously "-gdb-set target-async off" affected both MI execution
2646 commands and CLI execution commands.
2648 *** Changes in GDB 7.7
2650 * Improved support for process record-replay and reverse debugging on
2651 arm*-linux* targets. Support for thumb32 and syscall instruction
2652 recording has been added.
2654 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
2656 * GDB now supports Fission DWP file format version 2.
2657 http://gcc.gnu.org/wiki/DebugFission
2659 * New convenience function "$_isvoid", to check whether an expression
2660 is void. A void expression is an expression where the type of the
2661 result is "void". For example, some convenience variables may be
2662 "void" when evaluated (e.g., "$_exitcode" before the execution of
2663 the program being debugged; or an undefined convenience variable).
2664 Another example, when calling a function whose return type is
2667 * The "maintenance print objfiles" command now takes an optional regexp.
2669 * The "catch syscall" command now works on arm*-linux* targets.
2671 * GDB now consistently shows "<not saved>" when printing values of
2672 registers the debug info indicates have not been saved in the frame
2673 and there's nowhere to retrieve them from
2674 (callee-saved/call-clobbered registers):
2679 (gdb) info registers rax
2682 Before, the former would print "<optimized out>", and the latter
2683 "*value not available*".
2685 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
2690 ** Frame filters and frame decorators have been added.
2691 ** Temporary breakpoints are now supported.
2692 ** Line tables representation has been added.
2693 ** New attribute 'parent_type' for gdb.Field objects.
2694 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
2695 ** New attribute 'name' for gdb.Type objects.
2699 Nios II ELF nios2*-*-elf
2700 Nios II GNU/Linux nios2*-*-linux
2701 Texas Instruments MSP430 msp430*-*-elf
2703 * Removed native configurations
2705 Support for these a.out NetBSD and OpenBSD obsolete configurations has
2706 been removed. ELF variants of these configurations are kept supported.
2708 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
2709 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
2710 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
2711 i[34567]86-*-openbsd3.[0-3]
2712 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
2713 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
2714 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
2718 Like "catch throw", but catches a re-thrown exception.
2719 maint check-psymtabs
2720 Renamed from old "maint check-symtabs".
2722 Perform consistency checks on symtabs.
2723 maint expand-symtabs
2724 Expand symtabs matching an optional regexp.
2727 Display the details of GDB configure-time options.
2729 maint set|show per-command
2730 maint set|show per-command space
2731 maint set|show per-command time
2732 maint set|show per-command symtab
2733 Enable display of per-command gdb resource usage.
2735 remove-symbol-file FILENAME
2736 remove-symbol-file -a ADDRESS
2737 Remove a symbol file added via add-symbol-file. The file to remove
2738 can be identified by its filename or by an address that lies within
2739 the boundaries of this symbol file in memory.
2742 info exceptions REGEXP
2743 Display the list of Ada exceptions defined in the program being
2744 debugged. If provided, only the exceptions whose names match REGEXP
2749 set debug symfile off|on
2751 Control display of debugging info regarding reading symbol files and
2752 symbol tables within those files
2754 set print raw frame-arguments
2755 show print raw frame-arguments
2756 Set/show whether to print frame arguments in raw mode,
2757 disregarding any defined pretty-printers.
2759 set remote trace-status-packet
2760 show remote trace-status-packet
2761 Set/show the use of remote protocol qTStatus packet.
2765 Control display of debugging messages related to Nios II targets.
2769 Control whether target-assisted range stepping is enabled.
2771 set startup-with-shell
2772 show startup-with-shell
2773 Specifies whether Unix child processes are started via a shell or
2778 Use the target memory cache for accesses to the code segment. This
2779 improves performance of remote debugging (particularly disassembly).
2781 * You can now use a literal value 'unlimited' for options that
2782 interpret 0 or -1 as meaning "unlimited". E.g., "set
2783 trace-buffer-size unlimited" is now an alias for "set
2784 trace-buffer-size -1" and "set height unlimited" is now an alias for
2787 * The "set debug symtab-create" debugging option of GDB has been changed to
2788 accept a verbosity level. 0 means "off", 1 provides basic debugging
2789 output, and values of 2 or greater provides more verbose output.
2791 * New command-line options
2793 Display the details of GDB configure-time options.
2795 * The command 'tsave' can now support new option '-ctf' to save trace
2796 buffer in Common Trace Format.
2798 * Newly installed $prefix/bin/gcore acts as a shell interface for the
2801 * GDB now implements the C++ 'typeid' operator.
2803 * The new convenience variable $_exception holds the exception being
2804 thrown or caught at an exception-related catchpoint.
2806 * The exception-related catchpoints, like "catch throw", now accept a
2807 regular expression which can be used to filter exceptions by type.
2809 * The new convenience variable $_exitsignal is automatically set to
2810 the terminating signal number when the program being debugged dies
2811 due to an uncaught signal.
2815 ** All MI commands now accept an optional "--language" option.
2816 Support for this feature can be verified by using the "-list-features"
2817 command, which should contain "language-option".
2819 ** The new command -info-gdb-mi-command allows the user to determine
2820 whether a GDB/MI command is supported or not.
2822 ** The "^error" result record returned when trying to execute an undefined
2823 GDB/MI command now provides a variable named "code" whose content is the
2824 "undefined-command" error code. Support for this feature can be verified
2825 by using the "-list-features" command, which should contain
2826 "undefined-command-error-code".
2828 ** The -trace-save MI command can optionally save trace buffer in Common
2831 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2833 ** The command -data-list-register-values now accepts an optional
2834 "--skip-unavailable" option. When used, only the available registers
2837 ** The new command -trace-frame-collected dumps collected variables,
2838 computed expressions, tvars, memory and registers in a traceframe.
2840 ** The commands -stack-list-locals, -stack-list-arguments and
2841 -stack-list-variables now accept an option "--skip-unavailable".
2842 When used, only the available locals or arguments are displayed.
2844 ** The -exec-run command now accepts an optional "--start" option.
2845 When used, the command follows the same semantics as the "start"
2846 command, stopping the program's execution at the start of its
2847 main subprogram. Support for this feature can be verified using
2848 the "-list-features" command, which should contain
2849 "exec-run-start-option".
2851 ** The new commands -catch-assert and -catch-exceptions insert
2852 catchpoints stopping the program when Ada exceptions are raised.
2854 ** The new command -info-ada-exceptions provides the equivalent of
2855 the new "info exceptions" command.
2857 * New system-wide configuration scripts
2858 A GDB installation now provides scripts suitable for use as system-wide
2859 configuration scripts for the following systems:
2863 * GDB now supports target-assigned range stepping with remote targets.
2864 This improves the performance of stepping source lines by reducing
2865 the number of control packets from/to GDB. See "New remote packets"
2868 * GDB now understands the element 'tvar' in the XML traceframe info.
2869 It has the id of the collected trace state variables.
2871 * On S/390 targets that provide the transactional-execution feature,
2872 the program interruption transaction diagnostic block (TDB) is now
2873 represented as a number of additional "registers" in GDB.
2875 * New remote packets
2879 The vCont packet supports a new 'r' action, that tells the remote
2880 stub to step through an address range itself, without GDB
2881 involvemement at each single-step.
2883 qXfer:libraries-svr4:read's annex
2884 The previously unused annex of the qXfer:libraries-svr4:read packet
2885 is now used to support passing an argument list. The remote stub
2886 reports support for this argument list to GDB's qSupported query.
2887 The defined arguments are "start" and "prev", used to reduce work
2888 necessary for library list updating, resulting in significant
2891 * New features in the GDB remote stub, GDBserver
2893 ** GDBserver now supports target-assisted range stepping. Currently
2894 enabled on x86/x86_64 GNU/Linux targets.
2896 ** GDBserver now adds element 'tvar' in the XML in the reply to
2897 'qXfer:traceframe-info:read'. It has the id of the collected
2898 trace state variables.
2900 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2903 * New 'z' formatter for printing and examining memory, this displays the
2904 value as hexadecimal zero padded on the left to the size of the type.
2906 * GDB can now use Windows x64 unwinding data.
2908 * The "set remotebaud" command has been replaced by "set serial baud".
2909 Similarly, "show remotebaud" has been replaced by "show serial baud".
2910 The "set remotebaud" and "show remotebaud" commands are still available
2911 to provide backward compatibility with older versions of GDB.
2913 *** Changes in GDB 7.6
2915 * Target record has been renamed to record-full.
2916 Record/replay is now enabled with the "record full" command.
2917 This also affects settings that are associated with full record/replay
2918 that have been moved from "set/show record" to "set/show record full":
2920 set|show record full insn-number-max
2921 set|show record full stop-at-limit
2922 set|show record full memory-query
2924 * A new record target "record-btrace" has been added. The new target
2925 uses hardware support to record the control-flow of a process. It
2926 does not support replaying the execution, but it implements the
2927 below new commands for investigating the recorded execution log.
2928 This new recording method can be enabled using:
2932 The "record-btrace" target is only available on Intel Atom processors
2933 and requires a Linux kernel 2.6.32 or later.
2935 * Two new commands have been added for record/replay to give information
2936 about the recorded execution without having to replay the execution.
2937 The commands are only supported by "record btrace".
2939 record instruction-history prints the execution history at
2940 instruction granularity
2942 record function-call-history prints the execution history at
2943 function granularity
2945 * New native configurations
2947 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2948 FreeBSD/powerpc powerpc*-*-freebsd
2949 x86_64/Cygwin x86_64-*-cygwin*
2950 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2954 ARM AArch64 aarch64*-*-elf
2955 ARM AArch64 GNU/Linux aarch64*-*-linux
2956 Lynx 178 PowerPC powerpc-*-lynx*178
2957 x86_64/Cygwin x86_64-*-cygwin*
2958 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2960 * If the configured location of system.gdbinit file (as given by the
2961 --with-system-gdbinit option at configure time) is in the
2962 data-directory (as specified by --with-gdb-datadir at configure
2963 time) or in one of its subdirectories, then GDB will look for the
2964 system-wide init file in the directory specified by the
2965 --data-directory command-line option.
2967 * New command line options:
2969 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2970 other initialization files, unlike -nx which disables all of them.
2972 * Removed command line options
2974 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2977 * The 'ptype' and 'whatis' commands now accept an argument to control
2980 * 'info proc' now works on some core files.
2984 ** Vectors can be created with gdb.Type.vector.
2986 ** Python's atexit.register now works in GDB.
2988 ** Types can be pretty-printed via a Python API.
2990 ** Python 3 is now supported (in addition to Python 2.4 or later)
2992 ** New class gdb.Architecture exposes GDB's internal representation
2993 of architecture in the Python API.
2995 ** New method Frame.architecture returns the gdb.Architecture object
2996 corresponding to the frame's architecture.
2998 * New Python-based convenience functions:
3000 ** $_memeq(buf1, buf2, length)
3001 ** $_streq(str1, str2)
3003 ** $_regex(str, regex)
3005 * The 'cd' command now defaults to using '~' (the home directory) if not
3008 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
3009 default for GCC since November 2000.
3011 * The command 'forward-search' can now be abbreviated as 'fo'.
3013 * The command 'info tracepoints' can now display 'installed on target'
3014 or 'not installed on target' for each non-pending location of tracepoint.
3016 * New configure options
3018 --enable-libmcheck/--disable-libmcheck
3019 By default, development versions are built with -lmcheck on hosts
3020 that support it, in order to help track memory corruption issues.
3021 Release versions, on the other hand, are built without -lmcheck
3022 by default. The --enable-libmcheck/--disable-libmcheck configure
3023 options allow the user to override that default.
3024 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
3025 This configure option allows the user to build GDB with
3026 libbabeltrace using which GDB can read Common Trace Format data.
3028 * New commands (for set/show, see "New options" below)
3031 Catch signals. This is similar to "handle", but allows commands and
3032 conditions to be attached.
3035 List the BFDs known to GDB.
3037 python-interactive [command]
3039 Start a Python interactive prompt, or evaluate the optional command
3040 and print the result of expressions.
3043 "py" is a new alias for "python".
3045 enable type-printer [name]...
3046 disable type-printer [name]...
3047 Enable or disable type printers.
3051 ** For the Renesas Super-H architecture, the "regs" command has been removed
3052 (has been deprecated in GDB 7.5), and "info all-registers" should be used
3057 set print type methods (on|off)
3058 show print type methods
3059 Control whether method declarations are displayed by "ptype".
3060 The default is to show them.
3062 set print type typedefs (on|off)
3063 show print type typedefs
3064 Control whether typedef definitions are displayed by "ptype".
3065 The default is to show them.
3067 set filename-display basename|relative|absolute
3068 show filename-display
3069 Control the way in which filenames is displayed.
3070 The default is "relative", which preserves previous behavior.
3072 set trace-buffer-size
3073 show trace-buffer-size
3074 Request target to change the size of trace buffer.
3076 set remote trace-buffer-size-packet auto|on|off
3077 show remote trace-buffer-size-packet
3078 Control the use of the remote protocol `QTBuffer:size' packet.
3082 Control display of debugging messages related to ARM AArch64.
3085 set debug coff-pe-read
3086 show debug coff-pe-read
3087 Control display of debugging messages related to reading of COFF/PE
3092 Control display of debugging messages related to Mach-O symbols
3095 set debug notification
3096 show debug notification
3097 Control display of debugging info for async remote notification.
3101 ** Command parameter changes are now notified using new async record
3102 "=cmd-param-changed".
3103 ** Trace frame changes caused by command "tfind" are now notified using
3104 new async record "=traceframe-changed".
3105 ** The creation, deletion and modification of trace state variables
3106 are now notified using new async records "=tsv-created",
3107 "=tsv-deleted" and "=tsv-modified".
3108 ** The start and stop of process record are now notified using new
3109 async record "=record-started" and "=record-stopped".
3110 ** Memory changes are now notified using new async record
3112 ** The data-disassemble command response will include a "fullname" field
3113 containing the absolute file name when source has been requested.
3114 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
3115 command, to allow pattern filling of memory areas.
3116 ** New commands "-catch-load"/"-catch-unload" added for intercepting
3117 library load/unload events.
3118 ** The response to breakpoint commands and breakpoint async records
3119 includes an "installed" field containing a boolean state about each
3120 non-pending tracepoint location is whether installed on target or not.
3121 ** Output of the "-trace-status" command includes a "trace-file" field
3122 containing the name of the trace file being examined. This field is
3123 optional, and only present when examining a trace file.
3124 ** The "fullname" field is now always present along with the "file" field,
3125 even if the file cannot be found by GDB.
3127 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
3128 You must have the LZMA library available when configuring GDB for this
3129 feature to be enabled. For more information, see:
3130 http://fedoraproject.org/wiki/Features/MiniDebugInfo
3132 * New remote packets
3135 Set the size of trace buffer. The remote stub reports support for this
3136 packet to gdb's qSupported query.
3139 Enable Branch Trace Store (BTS)-based branch tracing for the current
3140 thread. The remote stub reports support for this packet to gdb's
3144 Disable branch tracing for the current thread. The remote stub reports
3145 support for this packet to gdb's qSupported query.
3148 Read the traced branches for the current thread. The remote stub
3149 reports support for this packet to gdb's qSupported query.
3151 *** Changes in GDB 7.5
3153 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
3154 for more x32 ABI info.
3156 * GDB now supports access to MIPS DSP registers on Linux targets.
3158 * GDB now supports debugging microMIPS binaries.
3160 * The "info os" command on GNU/Linux can now display information on
3161 several new classes of objects managed by the operating system:
3162 "info os procgroups" lists process groups
3163 "info os files" lists file descriptors
3164 "info os sockets" lists internet-domain sockets
3165 "info os shm" lists shared-memory regions
3166 "info os semaphores" lists semaphores
3167 "info os msg" lists message queues
3168 "info os modules" lists loaded kernel modules
3170 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
3171 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
3172 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
3173 options and inspect the probe arguments using the new $_probe_arg family
3174 of convenience variables. You can obtain more information about SystemTap
3175 in <http://sourceware.org/systemtap/>.
3177 * GDB now supports reversible debugging on ARM, it allows you to
3178 debug basic ARM and THUMB instructions, and provides
3179 record/replay support.
3181 * The option "symbol-reloading" has been deleted as it is no longer used.
3185 ** GDB commands implemented in Python can now be put in command class
3188 ** The "maint set python print-stack on|off" is now deleted.
3190 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
3191 apply "flag enum"-style pretty-printing to any enum.
3193 ** gdb.lookup_symbol can now work when there is no current frame.
3195 ** gdb.Symbol now has a 'line' attribute, holding the line number in
3196 the source at which the symbol was defined.
3198 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
3199 method 'value'. The former indicates whether the symbol needs a
3200 frame in order to compute its value, and the latter computes the
3203 ** A new method 'referenced_value' on gdb.Value objects which can
3204 dereference pointer as well as C++ reference values.
3206 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
3207 which return the global and static blocks (as gdb.Block objects),
3208 of the underlying symbol table, respectively.
3210 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
3211 object associated with a PC value.
3213 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
3214 of the address range occupied by code for the current source line.
3216 * Go language support.
3217 GDB now supports debugging programs written in the Go programming
3220 * GDBserver now supports stdio connections.
3221 E.g. (gdb) target remote | ssh myhost gdbserver - hello
3223 * The binary "gdbtui" can no longer be built or installed.
3224 Use "gdb -tui" instead.
3226 * GDB will now print "flag" enums specially. A flag enum is one where
3227 all the enumerator values have no bits in common when pairwise
3228 "and"ed. When printing a value whose type is a flag enum, GDB will
3229 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
3230 (gdb) print (enum E) 3
3233 * The filename part of a linespec will now match trailing components
3234 of a source file name. For example, "break gcc/expr.c:1000" will
3235 now set a breakpoint in build/gcc/expr.c, but not
3236 build/libcpp/expr.c.
3238 * The "info proc" and "generate-core-file" commands will now also
3239 work on remote targets connected to GDBserver on Linux.
3241 * The command "info catch" has been removed. It has been disabled
3242 since December 2007.
3244 * The "catch exception" and "catch assert" commands now accept
3245 a condition at the end of the command, much like the "break"
3246 command does. For instance:
3248 (gdb) catch exception Constraint_Error if Barrier = True
3250 Previously, it was possible to add a condition to such catchpoints,
3251 but it had to be done as a second step, after the catchpoint had been
3252 created, using the "condition" command.
3254 * The "info static-tracepoint-marker" command will now also work on
3255 native Linux targets with in-process agent.
3257 * GDB can now set breakpoints on inlined functions.
3259 * The .gdb_index section has been updated to include symbols for
3260 inlined functions. GDB will ignore older .gdb_index sections by
3261 default, which could cause symbol files to be loaded more slowly
3262 until their .gdb_index sections can be recreated. The new command
3263 "set use-deprecated-index-sections on" will cause GDB to use any older
3264 .gdb_index sections it finds. This will restore performance, but the
3265 ability to set breakpoints on inlined functions will be lost in symbol
3266 files with older .gdb_index sections.
3268 The .gdb_index section has also been updated to record more information
3269 about each symbol. This speeds up the "info variables", "info functions"
3270 and "info types" commands when used with programs having the .gdb_index
3271 section, as well as speeding up debugging with shared libraries using
3272 the .gdb_index section.
3274 * Ada support for GDB/MI Variable Objects has been added.
3276 * GDB can now support 'breakpoint always-inserted mode' in 'record'
3281 ** New command -info-os is the MI equivalent of "info os".
3283 ** Output logs ("set logging" and related) now include MI output.
3287 ** "set use-deprecated-index-sections on|off"
3288 "show use-deprecated-index-sections on|off"
3289 Controls the use of deprecated .gdb_index sections.
3291 ** "catch load" and "catch unload" can be used to stop when a shared
3292 library is loaded or unloaded, respectively.
3294 ** "enable count" can be used to auto-disable a breakpoint after
3297 ** "info vtbl" can be used to show the virtual method tables for
3298 C++ and Java objects.
3300 ** "explore" and its sub commands "explore value" and "explore type"
3301 can be used to recursively explore values and types of
3302 expressions. These commands are available only if GDB is
3303 configured with '--with-python'.
3305 ** "info auto-load" shows status of all kinds of auto-loaded files,
3306 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
3307 sequences of commands files, "info auto-load python-scripts"
3308 shows status of auto-loading Python script files,
3309 "info auto-load local-gdbinit" shows status of loading init file
3310 (.gdbinit) from current directory and "info auto-load libthread-db" shows
3311 status of inferior specific thread debugging shared library loading.
3313 ** "info auto-load-scripts", "set auto-load-scripts on|off"
3314 and "show auto-load-scripts" commands have been deprecated, use their
3315 "info auto-load python-scripts", "set auto-load python-scripts on|off"
3316 and "show auto-load python-scripts" counterparts instead.
3318 ** "dprintf location,format,args..." creates a dynamic printf, which
3319 is basically a breakpoint that does a printf and immediately
3320 resumes your program's execution, so it is like a printf that you
3321 can insert dynamically at runtime instead of at compiletime.
3323 ** "set print symbol"
3325 Controls whether GDB attempts to display the symbol, if any,
3326 corresponding to addresses it prints. This defaults to "on", but
3327 you can set it to "off" to restore GDB's previous behavior.
3329 * Deprecated commands
3331 ** For the Renesas Super-H architecture, the "regs" command has been
3332 deprecated, and "info all-registers" should be used instead.
3336 Renesas RL78 rl78-*-elf
3337 HP OpenVMS ia64 ia64-hp-openvms*
3339 * GDBserver supports evaluation of breakpoint conditions. When
3340 support is advertised by GDBserver, GDB may be told to send the
3341 breakpoint conditions in bytecode form to GDBserver. GDBserver
3342 will only report the breakpoint trigger to GDB when its condition
3347 set mips compression
3348 show mips compression
3349 Select the compressed ISA encoding used in functions that have no symbol
3350 information available. The encoding can be set to either of:
3353 and is updated automatically from ELF file flags if available.
3355 set breakpoint condition-evaluation
3356 show breakpoint condition-evaluation
3357 Control whether breakpoint conditions are evaluated by GDB ("host") or by
3358 GDBserver ("target"). Default option "auto" chooses the most efficient
3360 This option can improve debugger efficiency depending on the speed of the
3364 Disable auto-loading globally.
3367 Show auto-loading setting of all kinds of auto-loaded files.
3369 set auto-load gdb-scripts on|off
3370 show auto-load gdb-scripts
3371 Control auto-loading of GDB canned sequences of commands files.
3373 set auto-load python-scripts on|off
3374 show auto-load python-scripts
3375 Control auto-loading of Python script files.
3377 set auto-load local-gdbinit on|off
3378 show auto-load local-gdbinit
3379 Control loading of init file (.gdbinit) from current directory.
3381 set auto-load libthread-db on|off
3382 show auto-load libthread-db
3383 Control auto-loading of inferior specific thread debugging shared library.
3385 set auto-load scripts-directory <dir1>[:<dir2>...]
3386 show auto-load scripts-directory
3387 Set a list of directories from which to load auto-loaded scripts.
3388 Automatically loaded Python scripts and GDB scripts are located in one
3389 of the directories listed by this option.
3390 The delimiter (':' above) may differ according to the host platform.
3392 set auto-load safe-path <dir1>[:<dir2>...]
3393 show auto-load safe-path
3394 Set a list of directories from which it is safe to auto-load files.
3395 The delimiter (':' above) may differ according to the host platform.
3397 set debug auto-load on|off
3398 show debug auto-load
3399 Control display of debugging info for auto-loading the files above.
3401 set dprintf-style gdb|call|agent
3403 Control the way in which a dynamic printf is performed; "gdb"
3404 requests a GDB printf command, while "call" causes dprintf to call a
3405 function in the inferior. "agent" requests that the target agent
3406 (such as GDBserver) do the printing.
3408 set dprintf-function <expr>
3409 show dprintf-function
3410 set dprintf-channel <expr>
3411 show dprintf-channel
3412 Set the function and optional first argument to the call when using
3413 the "call" style of dynamic printf.
3415 set disconnected-dprintf on|off
3416 show disconnected-dprintf
3417 Control whether agent-style dynamic printfs continue to be in effect
3418 after GDB disconnects.
3420 * New configure options
3422 --with-auto-load-dir
3423 Configure default value for the 'set auto-load scripts-directory'
3424 setting above. It defaults to '$debugdir:$datadir/auto-load',
3425 $debugdir representing global debugging info directories (available
3426 via 'show debug-file-directory') and $datadir representing GDB's data
3427 directory (available via 'show data-directory').
3429 --with-auto-load-safe-path
3430 Configure default value for the 'set auto-load safe-path' setting
3431 above. It defaults to the --with-auto-load-dir setting.
3433 --without-auto-load-safe-path
3434 Set 'set auto-load safe-path' to '/', effectively disabling this
3437 * New remote packets
3439 z0/z1 conditional breakpoints extension
3441 The z0/z1 breakpoint insertion packets have been extended to carry
3442 a list of conditional expressions over to the remote stub depending on the
3443 condition evaluation mode. The use of this extension can be controlled
3444 via the "set remote conditional-breakpoints-packet" command.
3448 Specify the signals which the remote stub may pass to the debugged
3449 program without GDB involvement.
3451 * New command line options
3453 --init-command=FILE, -ix Like --command, -x but execute it
3454 before loading inferior.
3455 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
3456 execute it before loading inferior.
3458 *** Changes in GDB 7.4
3460 * GDB now handles ambiguous linespecs more consistently; the existing
3461 FILE:LINE support has been expanded to other types of linespecs. A
3462 breakpoint will now be set on all matching locations in all
3463 inferiors, and locations will be added or removed according to
3466 * GDB now allows you to skip uninteresting functions and files when
3467 stepping with the "skip function" and "skip file" commands.
3469 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
3470 and "show remote hardware-watchpoint-length-limit". These allows to
3471 set or show the maximum length limit (in bytes) of a remote
3472 target hardware watchpoint.
3474 This allows e.g. to use "unlimited" hardware watchpoints with the
3475 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
3476 watchpoints are slower than real hardware watchpoints but are
3477 significantly faster than gdb software watchpoints.
3481 ** The register_pretty_printer function in module gdb.printing now takes
3482 an optional `replace' argument. If True, the new printer replaces any
3485 ** The "maint set python print-stack on|off" command has been
3486 deprecated and will be deleted in GDB 7.5.
3487 A new command: "set python print-stack none|full|message" has
3488 replaced it. Additionally, the default for "print-stack" is
3489 now "message", which just prints the error message without
3492 ** A prompt substitution hook (prompt_hook) is now available to the
3495 ** A new Python module, gdb.prompt has been added to the GDB Python
3496 modules library. This module provides functionality for
3497 escape sequences in prompts (used by set/show
3498 extended-prompt). These escape sequences are replaced by their
3499 corresponding value.
3501 ** Python commands and convenience-functions located in
3502 'data-directory'/python/gdb/command and
3503 'data-directory'/python/gdb/function are now automatically loaded
3506 ** Blocks now provide four new attributes. global_block and
3507 static_block will return the global and static blocks
3508 respectively. is_static and is_global are boolean attributes
3509 that indicate if the block is one of those two types.
3511 ** Symbols now provide the "type" attribute, the type of the symbol.
3513 ** The "gdb.breakpoint" function has been deprecated in favor of
3516 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
3517 of a function. This class is based on the "finish" command
3518 available in the CLI.
3520 ** Type objects for struct and union types now allow access to
3521 the fields using standard Python dictionary (mapping) methods.
3522 For example, "some_type['myfield']" now works, as does
3523 "some_type.items()".
3525 ** A new event "gdb.new_objfile" has been added, triggered by loading a
3528 ** A new function, "deep_items" has been added to the gdb.types
3529 module in the GDB Python modules library. This function returns
3530 an iterator over the fields of a struct or union type. Unlike
3531 the standard Python "iteritems" method, it will recursively traverse
3532 any anonymous fields.
3536 ** "*stopped" events can report several new "reason"s, such as
3539 ** Breakpoint changes are now notified using new async records, like
3540 "=breakpoint-modified".
3542 ** New command -ada-task-info.
3544 * libthread-db-search-path now supports two special values: $sdir and $pdir.
3545 $sdir specifies the default system locations of shared libraries.
3546 $pdir specifies the directory where the libpthread used by the application
3549 GDB no longer looks in $sdir and $pdir after it has searched the directories
3550 mentioned in libthread-db-search-path. If you want to search those
3551 directories, they must be specified in libthread-db-search-path.
3552 The default value of libthread-db-search-path on GNU/Linux and Solaris
3553 systems is now "$sdir:$pdir".
3555 $pdir is not supported by gdbserver, it is currently ignored.
3556 $sdir is supported by gdbserver.
3558 * New configure option --with-iconv-bin.
3559 When using the internationalization support like the one in the GNU C
3560 library, GDB will invoke the "iconv" program to get a list of supported
3561 character sets. If this program lives in a non-standard location, one can
3562 use this option to specify where to find it.
3564 * When natively debugging programs on PowerPC BookE processors running
3565 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
3566 watchpoints, which specify a mask in addition to an address to watch.
3567 The mask specifies that some bits of an address (the bits which are
3568 reset in the mask) should be ignored when matching the address accessed
3569 by the inferior against the watchpoint address. See the "PowerPC Embedded"
3570 section in the user manual for more details.
3572 * The new option --once causes GDBserver to stop listening for connections once
3573 the first connection is made. The listening port used by GDBserver will
3574 become available after that.
3576 * New commands "info macros" and "alias" have been added.
3578 * New function parameters suffix @entry specifies value of function parameter
3579 at the time the function got called. Entry values are available only since
3585 "!" is now an alias of the "shell" command.
3586 Note that no space is needed between "!" and SHELL COMMAND.
3590 watch EXPRESSION mask MASK_VALUE
3591 The watch command now supports the mask argument which allows creation
3592 of masked watchpoints, if the current architecture supports this feature.
3594 info auto-load-scripts [REGEXP]
3595 This command was formerly named "maintenance print section-scripts".
3596 It is now generally useful and is no longer a maintenance-only command.
3598 info macro [-all] [--] MACRO
3599 The info macro command has new options `-all' and `--'. The first for
3600 printing all definitions of a macro. The second for explicitly specifying
3601 the end of arguments and the beginning of the macro name in case the macro
3602 name starts with a hyphen.
3604 collect[/s] EXPRESSIONS
3605 The tracepoint collect command now takes an optional modifier "/s"
3606 that directs it to dereference pointer-to-character types and
3607 collect the bytes of memory up to a zero byte. The behavior is
3608 similar to what you see when you use the regular print command on a
3609 string. An optional integer following the "/s" sets a bound on the
3610 number of bytes that will be collected.
3613 The trace start command now interprets any supplied arguments as a
3614 note to be recorded with the trace run, with an effect similar to
3615 setting the variable trace-notes.
3618 The trace stop command now interprets any arguments as a note to be
3619 mentioned along with the tstatus report that the trace was stopped
3620 with a command. The effect is similar to setting the variable
3623 * Tracepoints can now be enabled and disabled at any time after a trace
3624 experiment has been started using the standard "enable" and "disable"
3625 commands. It is now possible to start a trace experiment with no enabled
3626 tracepoints; GDB will display a warning, but will allow the experiment to
3627 begin, assuming that tracepoints will be enabled as needed while the trace
3630 * Fast tracepoints on 32-bit x86-architectures can now be placed at
3631 locations with 4-byte instructions, when they were previously
3632 limited to locations with instructions of 5 bytes or longer.
3636 set debug dwarf2-read
3637 show debug dwarf2-read
3638 Turns on or off display of debugging messages related to reading
3639 DWARF debug info. The default is off.
3641 set debug symtab-create
3642 show debug symtab-create
3643 Turns on or off display of debugging messages related to symbol table
3644 creation. The default is off.
3647 show extended-prompt
3648 Set the GDB prompt, and allow escape sequences to be inserted to
3649 display miscellaneous information (see 'help set extended-prompt'
3650 for the list of sequences). This prompt (and any information
3651 accessed through the escape sequences) is updated every time the
3652 prompt is displayed.
3654 set print entry-values (both|compact|default|if-needed|no|only|preferred)
3655 show print entry-values
3656 Set printing of frame argument values at function entry. In some cases
3657 GDB can determine the value of function argument which was passed by the
3658 function caller, even if the value was modified inside the called function.
3660 set debug entry-values
3661 show debug entry-values
3662 Control display of debugging info for determining frame argument values at
3663 function entry and virtual tail call frames.
3665 set basenames-may-differ
3666 show basenames-may-differ
3667 Set whether a source file may have multiple base names.
3668 (A "base name" is the name of a file with the directory part removed.
3669 Example: The base name of "/home/user/hello.c" is "hello.c".)
3670 If set, GDB will canonicalize file names (e.g., expand symlinks)
3671 before comparing them. Canonicalization is an expensive operation,
3672 but it allows the same file be known by more than one base name.
3673 If not set (the default), all source files are assumed to have just
3674 one base name, and gdb will do file name comparisons more efficiently.
3680 Set a user name and notes for the current and any future trace runs.
3681 This is useful for long-running and/or disconnected traces, to
3682 inform others (or yourself) as to who is running the trace, supply
3683 contact information, or otherwise explain what is going on.
3685 set trace-stop-notes
3686 show trace-stop-notes
3687 Set a note attached to the trace run, that is displayed when the
3688 trace has been stopped by a tstop command. This is useful for
3689 instance as an explanation, if you are stopping a trace run that was
3690 started by someone else.
3692 * New remote packets
3696 Dynamically enable a tracepoint in a started trace experiment.
3700 Dynamically disable a tracepoint in a started trace experiment.
3704 Set the user and notes of the trace run.
3708 Query the current status of a tracepoint.
3712 Query the minimum length of instruction at which a fast tracepoint may
3715 * Dcache size (number of lines) and line-size are now runtime-configurable
3716 via "set dcache line" and "set dcache line-size" commands.
3720 Texas Instruments TMS320C6x tic6x-*-*
3724 Renesas RL78 rl78-*-elf
3726 *** Changes in GDB 7.3.1
3728 * The build failure for NetBSD and OpenBSD targets have now been fixed.
3730 *** Changes in GDB 7.3
3732 * GDB has a new command: "thread find [REGEXP]".
3733 It finds the thread id whose name, target id, or thread extra info
3734 matches the given regular expression.
3736 * The "catch syscall" command now works on mips*-linux* targets.
3738 * The -data-disassemble MI command now supports modes 2 and 3 for
3739 dumping the instruction opcodes.
3741 * New command line options
3743 -data-directory DIR Specify DIR as the "data-directory".
3744 This is mostly for testing purposes.
3746 * The "maint set python auto-load on|off" command has been renamed to
3747 "set auto-load-scripts on|off".
3749 * GDB has a new command: "set directories".
3750 It is like the "dir" command except that it replaces the
3751 source path list instead of augmenting it.
3753 * GDB now understands thread names.
3755 On GNU/Linux, "info threads" will display the thread name as set by
3756 prctl or pthread_setname_np.
3758 There is also a new command, "thread name", which can be used to
3759 assign a name internally for GDB to display.
3762 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
3763 has been integrated into GDB.
3767 ** The function gdb.Write now accepts an optional keyword 'stream'.
3768 This keyword, when provided, will direct the output to either
3769 stdout, stderr, or GDB's logging output.
3771 ** Parameters can now be be sub-classed in Python, and in particular
3772 you may implement the get_set_doc and get_show_doc functions.
3773 This improves how Parameter set/show documentation is processed
3774 and allows for more dynamic content.
3776 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
3777 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
3778 have an is_valid method.
3780 ** Breakpoints can now be sub-classed in Python, and in particular
3781 you may implement a 'stop' function that is executed each time
3782 the inferior reaches that breakpoint.
3784 ** New function gdb.lookup_global_symbol looks up a global symbol.
3786 ** GDB values in Python are now callable if the value represents a
3787 function. For example, if 'some_value' represents a function that
3788 takes two integer parameters and returns a value, you can call
3789 that function like so:
3791 result = some_value (10,20)
3793 ** Module gdb.types has been added.
3794 It contains a collection of utilities for working with gdb.Types objects:
3795 get_basic_type, has_field, make_enum_dict.
3797 ** Module gdb.printing has been added.
3798 It contains utilities for writing and registering pretty-printers.
3799 New classes: PrettyPrinter, SubPrettyPrinter,
3800 RegexpCollectionPrettyPrinter.
3801 New function: register_pretty_printer.
3803 ** New commands "info pretty-printers", "enable pretty-printer" and
3804 "disable pretty-printer" have been added.
3806 ** gdb.parameter("directories") is now available.
3808 ** New function gdb.newest_frame returns the newest frame in the
3811 ** The gdb.InferiorThread class has a new "name" attribute. This
3812 holds the thread's name.
3814 ** Python Support for Inferior events.
3815 Python scripts can add observers to be notified of events
3816 occurring in the process being debugged.
3817 The following events are currently supported:
3818 - gdb.events.cont Continue event.
3819 - gdb.events.exited Inferior exited event.
3820 - gdb.events.stop Signal received, and Breakpoint hit events.
3824 ** GDB now puts template parameters in scope when debugging in an
3825 instantiation. For example, if you have:
3827 template<int X> int func (void) { return X; }
3829 then if you step into func<5>, "print X" will show "5". This
3830 feature requires proper debuginfo support from the compiler; it
3831 was added to GCC 4.5.
3833 ** The motion commands "next", "finish", "until", and "advance" now
3834 work better when exceptions are thrown. In particular, GDB will
3835 no longer lose control of the inferior; instead, the GDB will
3836 stop the inferior at the point at which the exception is caught.
3837 This functionality requires a change in the exception handling
3838 code that was introduced in GCC 4.5.
3840 * GDB now follows GCC's rules on accessing volatile objects when
3841 reading or writing target state during expression evaluation.
3842 One notable difference to prior behavior is that "print x = 0"
3843 no longer generates a read of x; the value of the assignment is
3844 now always taken directly from the value being assigned.
3846 * GDB now has some support for using labels in the program's source in
3847 linespecs. For instance, you can use "advance label" to continue
3848 execution to a label.
3850 * GDB now has support for reading and writing a new .gdb_index
3851 section. This section holds a fast index of DWARF debugging
3852 information and can be used to greatly speed up GDB startup and
3853 operation. See the documentation for `save gdb-index' for details.
3855 * The "watch" command now accepts an optional "-location" argument.
3856 When used, this causes GDB to watch the memory referred to by the
3857 expression. Such a watchpoint is never deleted due to it going out
3860 * GDB now supports thread debugging of core dumps on GNU/Linux.
3862 GDB now activates thread debugging using the libthread_db library
3863 when debugging GNU/Linux core dumps, similarly to when debugging
3864 live processes. As a result, when debugging a core dump file, GDB
3865 is now able to display pthread_t ids of threads. For example, "info
3866 threads" shows the same output as when debugging the process when it
3867 was live. In earlier releases, you'd see something like this:
3870 * 1 LWP 6780 main () at main.c:10
3872 While now you see this:
3875 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3877 It is also now possible to inspect TLS variables when debugging core
3880 When debugging a core dump generated on a machine other than the one
3881 used to run GDB, you may need to point GDB at the correct
3882 libthread_db library with the "set libthread-db-search-path"
3883 command. See the user manual for more details on this command.
3885 * When natively debugging programs on PowerPC BookE processors running
3886 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3887 which stop execution of the inferior whenever it executes an instruction
3888 at any address within the specified range. See the "PowerPC Embedded"
3889 section in the user manual for more details.
3891 * New features in the GDB remote stub, GDBserver
3893 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3894 and i686 LynxOS (version 5.x).
3896 ** GDBserver is now supported on Blackfin Linux.
3898 * New native configurations
3900 ia64 HP-UX ia64-*-hpux*
3904 Analog Devices, Inc. Blackfin Processor bfin-*
3906 * Ada task switching is now supported on sparc-elf targets when
3907 debugging a program using the Ravenscar Profile. For more information,
3908 see the "Tasking Support when using the Ravenscar Profile" section
3909 in the GDB user manual.
3911 * Guile support was removed.
3913 * New features in the GNU simulator
3915 ** The --map-info flag lists all known core mappings.
3917 ** CFI flashes may be simulated via the "cfi" device.
3919 *** Changes in GDB 7.2
3921 * Shared library support for remote targets by default
3923 When GDB is configured for a generic, non-OS specific target, like
3924 for example, --target=arm-eabi or one of the many *-*-elf targets,
3925 GDB now queries remote stubs for loaded shared libraries using the
3926 `qXfer:libraries:read' packet. Previously, shared library support
3927 was always disabled for such configurations.
3931 ** Argument Dependent Lookup (ADL)
3933 In C++ ADL lookup directs function search to the namespaces of its
3934 arguments even if the namespace has not been imported.
3944 Here the compiler will search for `foo' in the namespace of 'b'
3945 and find A::foo. GDB now supports this. This construct is commonly
3946 used in the Standard Template Library for operators.
3948 ** Improved User Defined Operator Support
3950 In addition to member operators, GDB now supports lookup of operators
3951 defined in a namespace and imported with a `using' directive, operators
3952 defined in the global scope, operators imported implicitly from an
3953 anonymous namespace, and the ADL operators mentioned in the previous
3955 GDB now also supports proper overload resolution for all the previously
3956 mentioned flavors of operators.
3958 ** static const class members
3960 Printing of static const class members that are initialized in the
3961 class definition has been fixed.
3963 * Windows Thread Information Block access.
3965 On Windows targets, GDB now supports displaying the Windows Thread
3966 Information Block (TIB) structure. This structure is visible either
3967 by using the new command `info w32 thread-information-block' or, by
3968 dereferencing the new convenience variable named `$_tlb', a
3969 thread-specific pointer to the TIB. This feature is also supported
3970 when remote debugging using GDBserver.
3972 * Static tracepoints
3974 Static tracepoints are calls in the user program into a tracing
3975 library. One such library is a port of the LTTng kernel tracer to
3976 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3977 When debugging with GDBserver, GDB now supports combining the GDB
3978 tracepoint machinery with such libraries. For example: the user can
3979 use GDB to probe a static tracepoint marker (a call from the user
3980 program into the tracing library) with the new "strace" command (see
3981 "New commands" below). This creates a "static tracepoint" in the
3982 breakpoint list, that can be manipulated with the same feature set
3983 as fast and regular tracepoints. E.g., collect registers, local and
3984 global variables, collect trace state variables, and define
3985 tracepoint conditions. In addition, the user can collect extra
3986 static tracepoint marker specific data, by collecting the new
3987 $_sdata internal variable. When analyzing the trace buffer, you can
3988 inspect $_sdata like any other variable available to GDB. For more
3989 information, see the "Tracepoints" chapter in GDB user manual. New
3990 remote packets have been defined to support static tracepoints, see
3991 the "New remote packets" section below.
3993 * Better reconstruction of tracepoints after disconnected tracing
3995 GDB will attempt to download the original source form of tracepoint
3996 definitions when starting a trace run, and then will upload these
3997 upon reconnection to the target, resulting in a more accurate
3998 reconstruction of the tracepoints that are in use on the target.
4002 You can now exercise direct control over the ways that GDB can
4003 affect your program. For instance, you can disallow the setting of
4004 breakpoints, so that the program can run continuously (assuming
4005 non-stop mode). In addition, the "observer" variable is available
4006 to switch all of the different controls; in observer mode, GDB
4007 cannot affect the target's behavior at all, which is useful for
4008 tasks like diagnosing live systems in the field.
4010 * The new convenience variable $_thread holds the number of the
4013 * New remote packets
4017 Return the address of the Windows Thread Information Block of a given thread.
4021 In response to several of the tracepoint packets, the target may now
4022 also respond with a number of intermediate `qRelocInsn' request
4023 packets before the final result packet, to have GDB handle
4024 relocating an instruction to execute at a different address. This
4025 is particularly useful for stubs that support fast tracepoints. GDB
4026 reports support for this feature in the qSupported packet.
4030 List static tracepoint markers in the target program.
4034 List static tracepoint markers at a given address in the target
4037 qXfer:statictrace:read
4039 Read the static trace data collected (by a `collect $_sdata'
4040 tracepoint action). The remote stub reports support for this packet
4041 to gdb's qSupported query.
4045 Send the current settings of GDB's permission flags.
4049 Send part of the source (textual) form of a tracepoint definition,
4050 which includes location, conditional, and action list.
4052 * The source command now accepts a -s option to force searching for the
4053 script in the source search path even if the script name specifies
4056 * New features in the GDB remote stub, GDBserver
4058 - GDBserver now support tracepoints (including fast tracepoints, and
4059 static tracepoints). The feature is currently supported by the
4060 i386-linux and amd64-linux builds. See the "Tracepoints support
4061 in gdbserver" section in the manual for more information.
4063 GDBserver JIT compiles the tracepoint's conditional agent
4064 expression bytecode into native code whenever possible for low
4065 overhead dynamic tracepoints conditionals. For such tracepoints,
4066 an expression that examines program state is evaluated when the
4067 tracepoint is reached, in order to determine whether to capture
4068 trace data. If the condition is simple and false, processing the
4069 tracepoint finishes very quickly and no data is gathered.
4071 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
4072 for static tracepoints support.
4074 - GDBserver now supports x86_64 Windows 64-bit debugging.
4076 * GDB now sends xmlRegisters= in qSupported packet to indicate that
4077 it understands register description.
4079 * The --batch flag now disables pagination and queries.
4081 * X86 general purpose registers
4083 GDB now supports reading/writing byte, word and double-word x86
4084 general purpose registers directly. This means you can use, say,
4085 $ah or $ax to refer, respectively, to the byte register AH and
4086 16-bit word register AX that are actually portions of the 32-bit
4087 register EAX or 64-bit register RAX.
4089 * The `commands' command now accepts a range of breakpoints to modify.
4090 A plain `commands' following a command that creates multiple
4091 breakpoints affects all the breakpoints set by that command. This
4092 applies to breakpoints set by `rbreak', and also applies when a
4093 single `break' command creates multiple breakpoints (e.g.,
4094 breakpoints on overloaded c++ functions).
4096 * The `rbreak' command now accepts a filename specification as part of
4097 its argument, limiting the functions selected by the regex to those
4098 in the specified file.
4100 * Support for remote debugging Windows and SymbianOS shared libraries
4101 from Unix hosts has been improved. Non Windows GDB builds now can
4102 understand target reported file names that follow MS-DOS based file
4103 system semantics, such as file names that include drive letters and
4104 use the backslash character as directory separator. This makes it
4105 possible to transparently use the "set sysroot" and "set
4106 solib-search-path" on Unix hosts to point as host copies of the
4107 target's shared libraries. See the new command "set
4108 target-file-system-kind" described below, and the "Commands to
4109 specify files" section in the user manual for more information.
4113 eval template, expressions...
4114 Convert the values of one or more expressions under the control
4115 of the string template to a command line, and call it.
4117 set target-file-system-kind unix|dos-based|auto
4118 show target-file-system-kind
4119 Set or show the assumed file system kind for target reported file
4122 save breakpoints <filename>
4123 Save all current breakpoint definitions to a file suitable for use
4124 in a later debugging session. To read the saved breakpoint
4125 definitions, use the `source' command.
4127 `save tracepoints' is a new alias for `save-tracepoints'. The latter
4130 info static-tracepoint-markers
4131 Display information about static tracepoint markers in the target.
4133 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
4134 Define a static tracepoint by probing a marker at the given
4135 function, line, address, or marker ID.
4139 Enable and disable observer mode.
4141 set may-write-registers on|off
4142 set may-write-memory on|off
4143 set may-insert-breakpoints on|off
4144 set may-insert-tracepoints on|off
4145 set may-insert-fast-tracepoints on|off
4146 set may-interrupt on|off
4147 Set individual permissions for GDB effects on the target. Note that
4148 some of these settings can have undesirable or surprising
4149 consequences, particularly when changed in the middle of a session.
4150 For instance, disabling the writing of memory can prevent
4151 breakpoints from being inserted, cause single-stepping to fail, or
4152 even crash your program, if you disable after breakpoints have been
4153 inserted. However, GDB should not crash.
4155 set record memory-query on|off
4156 show record memory-query
4157 Control whether to stop the inferior if memory changes caused
4158 by an instruction cannot be recorded.
4163 The disassemble command now supports "start,+length" form of two arguments.
4167 ** GDB now provides a new directory location, called the python directory,
4168 where Python scripts written for GDB can be installed. The location
4169 of that directory is <data-directory>/python, where <data-directory>
4170 is the GDB data directory. For more details, see section `Scripting
4171 GDB using Python' in the manual.
4173 ** The GDB Python API now has access to breakpoints, symbols, symbol
4174 tables, program spaces, inferiors, threads and frame's code blocks.
4175 Additionally, GDB Parameters can now be created from the API, and
4176 manipulated via set/show in the CLI.
4178 ** New functions gdb.target_charset, gdb.target_wide_charset,
4179 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
4181 ** New exception gdb.GdbError.
4183 ** Pretty-printers are now also looked up in the current program space.
4185 ** Pretty-printers can now be individually enabled and disabled.
4187 ** GDB now looks for names of Python scripts to auto-load in a
4188 special section named `.debug_gdb_scripts', in addition to looking
4189 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
4191 * Tracepoint actions were unified with breakpoint commands. In particular,
4192 there are no longer differences in "info break" output for breakpoints and
4193 tracepoints and the "commands" command can be used for both tracepoints and
4194 regular breakpoints.
4198 ARM Symbian arm*-*-symbianelf*
4200 * D language support.
4201 GDB now supports debugging programs written in the D programming
4204 * GDB now supports the extended ptrace interface for PowerPC which is
4205 available since Linux kernel version 2.6.34. This automatically enables
4206 any hardware breakpoints and additional hardware watchpoints available in
4207 the processor. The old ptrace interface exposes just one hardware
4208 watchpoint and no hardware breakpoints.
4210 * GDB is now able to use the Data Value Compare (DVC) register available on
4211 embedded PowerPC processors to implement in hardware simple watchpoint
4212 conditions of the form:
4214 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
4216 This works in native GDB running on Linux kernels with the extended ptrace
4217 interface mentioned above.
4219 *** Changes in GDB 7.1
4223 ** Namespace Support
4225 GDB now supports importing of namespaces in C++. This enables the
4226 user to inspect variables from imported namespaces. Support for
4227 namepace aliasing has also been added. So, if a namespace is
4228 aliased in the current scope (e.g. namepace C=A; ) the user can
4229 print variables using the alias (e.g. (gdb) print C::x).
4233 All known bugs relating to the printing of virtual base class were
4234 fixed. It is now possible to call overloaded static methods using a
4239 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
4240 and reinterpret_cast<> are now handled by the C++ expression parser.
4244 Xilinx MicroBlaze microblaze-*-*
4249 Xilinx MicroBlaze microblaze
4252 * Multi-program debugging.
4254 GDB now has support for multi-program (a.k.a. multi-executable or
4255 multi-exec) debugging. This allows for debugging multiple inferiors
4256 simultaneously each running a different program under the same GDB
4257 session. See "Debugging Multiple Inferiors and Programs" in the
4258 manual for more information. This implied some user visible changes
4259 in the multi-inferior support. For example, "info inferiors" now
4260 lists inferiors that are not running yet or that have exited
4261 already. See also "New commands" and "New options" below.
4263 * New tracing features
4265 GDB's tracepoint facility now includes several new features:
4267 ** Trace state variables
4269 GDB tracepoints now include support for trace state variables, which
4270 are variables managed by the target agent during a tracing
4271 experiment. They are useful for tracepoints that trigger each
4272 other, so for instance one tracepoint can count hits in a variable,
4273 and then a second tracepoint has a condition that is true when the
4274 count reaches a particular value. Trace state variables share the
4275 $-syntax of GDB convenience variables, and can appear in both
4276 tracepoint actions and condition expressions. Use the "tvariable"
4277 command to create, and "info tvariables" to view; see "Trace State
4278 Variables" in the manual for more detail.
4282 GDB now includes an option for defining fast tracepoints, which
4283 targets may implement more efficiently, such as by installing a jump
4284 into the target agent rather than a trap instruction. The resulting
4285 speedup can be by two orders of magnitude or more, although the
4286 tradeoff is that some program locations on some target architectures
4287 might not allow fast tracepoint installation, for instance if the
4288 instruction to be replaced is shorter than the jump. To request a
4289 fast tracepoint, use the "ftrace" command, with syntax identical to
4290 the regular trace command.
4292 ** Disconnected tracing
4294 It is now possible to detach GDB from the target while it is running
4295 a trace experiment, then reconnect later to see how the experiment
4296 is going. In addition, a new variable disconnected-tracing lets you
4297 tell the target agent whether to continue running a trace if the
4298 connection is lost unexpectedly.
4302 GDB now has the ability to save the trace buffer into a file, and
4303 then use that file as a target, similarly to you can do with
4304 corefiles. You can select trace frames, print data that was
4305 collected in them, and use tstatus to display the state of the
4306 tracing run at the moment that it was saved. To create a trace
4307 file, use "tsave <filename>", and to use it, do "target tfile
4310 ** Circular trace buffer
4312 You can ask the target agent to handle the trace buffer as a
4313 circular buffer, discarding the oldest trace frames to make room for
4314 newer ones, by setting circular-trace-buffer to on. This feature may
4315 not be available for all target agents.
4320 The disassemble command, when invoked with two arguments, now requires
4321 the arguments to be comma-separated.
4324 The info variables command now displays variable definitions. Files
4325 which only declare a variable are not shown.
4328 The source command is now capable of sourcing Python scripts.
4329 This feature is dependent on the debugger being build with Python
4332 Related to this enhancement is also the introduction of a new command
4333 "set script-extension" (see below).
4335 * New commands (for set/show, see "New options" below)
4337 record save [<FILENAME>]
4338 Save a file (in core file format) containing the process record
4339 execution log for replay debugging at a later time.
4341 record restore <FILENAME>
4342 Restore the process record execution log that was saved at an
4343 earlier time, for replay debugging.
4345 add-inferior [-copies <N>] [-exec <FILENAME>]
4348 clone-inferior [-copies <N>] [ID]
4349 Make a new inferior ready to execute the same program another
4350 inferior has loaded.
4355 maint info program-spaces
4356 List the program spaces loaded into GDB.
4358 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
4359 show remote interrupt-sequence
4360 Allow the user to select one of ^C, a BREAK signal or BREAK-g
4361 as the sequence to the remote target in order to interrupt the execution.
4362 Ctrl-C is a default. Some system prefers BREAK which is high level of
4363 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
4364 Magic SysRq g. It is BREAK signal and character 'g'.
4366 set remote interrupt-on-connect [on | off]
4367 show remote interrupt-on-connect
4368 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
4369 remote target when gdb connects to it. This is needed when you debug
4372 set remotebreak [on | off]
4374 Deprecated. Use "set/show remote interrupt-sequence" instead.
4376 tvariable $NAME [ = EXP ]
4377 Create or modify a trace state variable.
4380 List trace state variables and their values.
4382 delete tvariable $NAME ...
4383 Delete one or more trace state variables.
4386 Evaluate the given expressions without collecting anything into the
4387 trace buffer. (Valid in tracepoint actions only.)
4389 ftrace FN / FILE:LINE / *ADDR
4390 Define a fast tracepoint at the given function, line, or address.
4392 * New expression syntax
4394 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
4395 GDB now parses 0b101010 identically with 42.
4399 set follow-exec-mode new|same
4400 show follow-exec-mode
4401 Control whether GDB reuses the same inferior across an exec call or
4402 creates a new one. This is useful to be able to restart the old
4403 executable after the inferior having done an exec call.
4405 set default-collect EXPR, ...
4406 show default-collect
4407 Define a list of expressions to be collected at each tracepoint.
4408 This is a useful way to ensure essential items are not overlooked,
4409 such as registers or a critical global variable.
4411 set disconnected-tracing
4412 show disconnected-tracing
4413 If set to 1, the target is instructed to continue tracing if it
4414 loses its connection to GDB. If 0, the target is to stop tracing
4417 set circular-trace-buffer
4418 show circular-trace-buffer
4419 If set to on, the target is instructed to use a circular trace buffer
4420 and discard the oldest trace frames instead of stopping the trace due
4421 to a full trace buffer. If set to off, the trace stops when the buffer
4422 fills up. Some targets may not support this.
4424 set script-extension off|soft|strict
4425 show script-extension
4426 If set to "off", the debugger does not perform any script language
4427 recognition, and all sourced files are assumed to be GDB scripts.
4428 If set to "soft" (the default), files are sourced according to
4429 filename extension, falling back to GDB scripts if the first
4431 If set to "strict", files are sourced according to filename extension.
4433 set ada trust-PAD-over-XVS on|off
4434 show ada trust-PAD-over-XVS
4435 If off, activate a workaround against a bug in the debugging information
4436 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
4437 the GCC sources for more information about the GNAT encoding and
4438 PAD types in particular). It is always safe to set this option to
4439 off, but this introduces a slight performance penalty. The default
4442 * Python API Improvements
4444 ** GDB provides the new class gdb.LazyString. This is useful in
4445 some pretty-printing cases. The new method gdb.Value.lazy_string
4446 provides a simple way to create objects of this type.
4448 ** The fields returned by gdb.Type.fields now have an
4449 `is_base_class' attribute.
4451 ** The new method gdb.Type.range returns the range of an array type.
4453 ** The new method gdb.parse_and_eval can be used to parse and
4454 evaluate an expression.
4456 * New remote packets
4459 Define a trace state variable.
4462 Get the current value of a trace state variable.
4465 Set desired tracing behavior upon disconnection.
4468 Set the trace buffer to be linear or circular.
4471 Get data about the tracepoints currently in use.
4475 Process record now works correctly with hardware watchpoints.
4477 Multiple bug fixes have been made to the mips-irix port, making it
4478 much more reliable. In particular:
4479 - Debugging threaded applications is now possible again. Previously,
4480 GDB would hang while starting the program, or while waiting for
4481 the program to stop at a breakpoint.
4482 - Attaching to a running process no longer hangs.
4483 - An error occurring while loading a core file has been fixed.
4484 - Changing the value of the PC register now works again. This fixes
4485 problems observed when using the "jump" command, or when calling
4486 a function from GDB, or even when assigning a new value to $pc.
4487 - With the "finish" and "return" commands, the return value for functions
4488 returning a small array is now correctly printed.
4489 - It is now possible to break on shared library code which gets executed
4490 during a shared library init phase (code executed while executing
4491 their .init section). Previously, the breakpoint would have no effect.
4492 - GDB is now able to backtrace through the signal handler for
4493 non-threaded programs.
4495 PIE (Position Independent Executable) programs debugging is now supported.
4496 This includes debugging execution of PIC (Position Independent Code) shared
4497 libraries although for that, it should be possible to run such libraries as an
4500 *** Changes in GDB 7.0
4502 * GDB now has an interface for JIT compilation. Applications that
4503 dynamically generate code can create symbol files in memory and register
4504 them with GDB. For users, the feature should work transparently, and
4505 for JIT developers, the interface is documented in the GDB manual in the
4506 "JIT Compilation Interface" chapter.
4508 * Tracepoints may now be conditional. The syntax is as for
4509 breakpoints; either an "if" clause appended to the "trace" command,
4510 or the "condition" command is available. GDB sends the condition to
4511 the target for evaluation using the same bytecode format as is used
4512 for tracepoint actions.
4514 * The disassemble command now supports: an optional /r modifier, print the
4515 raw instructions in hex as well as in symbolic form, and an optional /m
4516 modifier to print mixed source+assembly.
4518 * Process record and replay
4520 In a architecture environment that supports ``process record and
4521 replay'', ``process record and replay'' target can record a log of
4522 the process execution, and replay it with both forward and reverse
4525 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
4526 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
4527 set execution-direction {forward|reverse}, for targets that support
4530 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
4531 feature is available with a native GDB running on kernel version
4534 * GDB now has support for multi-byte and wide character sets on the
4535 target. Strings whose character type is wchar_t, char16_t, or
4536 char32_t are now correctly printed. GDB supports wide- and unicode-
4537 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
4538 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
4539 `printf'. This feature requires iconv to work properly; if your
4540 system does not have a working iconv, GDB can use GNU libiconv. See
4541 the installation instructions for more information.
4543 * GDB now supports automatic retrieval of shared library files from
4544 remote targets. To use this feature, specify a system root that begins
4545 with the `remote:' prefix, either via the `set sysroot' command or via
4546 the `--with-sysroot' configure-time option.
4548 * "info sharedlibrary" now takes an optional regex of libraries to show,
4549 and it now reports if a shared library has no debugging information.
4551 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
4552 now complete on file names.
4554 * When completing in expressions, gdb will attempt to limit
4555 completions to allowable structure or union fields, where appropriate.
4556 For instance, consider:
4558 # struct example { int f1; double f2; };
4559 # struct example variable;
4562 If the user types TAB at the end of this command line, the available
4563 completions will be "f1" and "f2".
4565 * Inlined functions are now supported. They show up in backtraces, and
4566 the "step", "next", and "finish" commands handle them automatically.
4568 * GDB now supports the token-splicing (##) and stringification (#)
4569 operators when expanding macros. It also supports variable-arity
4572 * GDB now supports inspecting extra signal information, exported by
4573 the new $_siginfo convenience variable. The feature is currently
4574 implemented on linux ARM, i386 and amd64.
4576 * GDB can now display the VFP floating point registers and NEON vector
4577 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
4578 can provide these registers (requires Linux 2.6.30 or later). Remote
4579 and simulator targets may also provide them.
4581 * New remote packets
4584 Search memory for a sequence of bytes.
4587 Turn off `+'/`-' protocol acknowledgments to permit more efficient
4588 operation over reliable transport links. Use of this packet is
4589 controlled by the `set remote noack-packet' command.
4592 Kill the process with the specified process ID. Use this in preference
4593 to `k' when multiprocess protocol extensions are supported.
4596 Obtains additional operating system information
4600 Read or write additional signal information.
4602 * Removed remote protocol undocumented extension
4604 An undocumented extension to the remote protocol's `S' stop reply
4605 packet that permitted the stub to pass a process id was removed.
4606 Remote servers should use the `T' stop reply packet instead.
4608 * GDB now supports multiple function calling conventions according to the
4609 DWARF-2 DW_AT_calling_convention function attribute.
4611 * The SH target utilizes the aforementioned change to distinguish between gcc
4612 and Renesas calling convention. It also adds the new CLI commands
4613 `set/show sh calling-convention'.
4615 * GDB can now read compressed debug sections, as produced by GNU gold
4616 with the --compress-debug-sections=zlib flag.
4618 * 64-bit core files are now supported on AIX.
4620 * Thread switching is now supported on Tru64.
4622 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
4623 which will be allocated using malloc later in program execution.
4625 * The qXfer:libraries:read remote protocol packet now allows passing a
4626 list of section offsets.
4628 * On GNU/Linux, GDB can now attach to stopped processes. Several race
4629 conditions handling signals delivered during attach or thread creation
4630 have also been fixed.
4632 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
4633 From the user's standpoint, all unqualified instances of True and False
4634 are treated as the standard definitions, regardless of context.
4636 * GDB now parses C++ symbol and type names more flexibly. For
4639 template<typename T> class C { };
4642 GDB will now correctly handle all of:
4644 ptype C<char const *>
4645 ptype C<char const*>
4646 ptype C<const char *>
4647 ptype C<const char*>
4649 * New features in the GDB remote stub, gdbserver
4651 - The "--wrapper" command-line argument tells gdbserver to use a
4652 wrapper program to launch programs for debugging.
4654 - On PowerPC and S/390 targets, it is now possible to use a single
4655 gdbserver executable to debug both 32-bit and 64-bit programs.
4656 (This requires gdbserver itself to be built as a 64-bit executable.)
4658 - gdbserver uses the new noack protocol mode for TCP connections to
4659 reduce communications latency, if also supported and enabled in GDB.
4661 - Support for the sparc64-linux-gnu target is now included in
4664 - The amd64-linux build of gdbserver now supports debugging both
4665 32-bit and 64-bit programs.
4667 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
4668 now support hardware watchpoints, and will use them automatically
4673 GDB now has support for scripting using Python. Whether this is
4674 available is determined at configure time.
4676 New GDB commands can now be written in Python.
4678 * Ada tasking support
4680 Ada tasks can now be inspected in GDB. The following commands have
4684 Print the list of Ada tasks.
4686 Print detailed information about task number N.
4688 Print the task number of the current task.
4690 Switch the context of debugging to task number N.
4692 * Support for user-defined prefixed commands. The "define" command can
4693 add new commands to existing prefixes, e.g. "target".
4695 * Multi-inferior, multi-process debugging.
4697 GDB now has generalized support for multi-inferior debugging. See
4698 "Debugging Multiple Inferiors" in the manual for more information.
4699 Although availability still depends on target support, the command
4700 set is more uniform now. The GNU/Linux specific multi-forks support
4701 has been migrated to this new framework. This implied some user
4702 visible changes; see "New commands" and also "Removed commands"
4705 * Target descriptions can now describe the target OS ABI. See the
4706 "Target Description Format" section in the user manual for more
4709 * Target descriptions can now describe "compatible" architectures
4710 to indicate that the target can execute applications for a different
4711 architecture in addition to those for the main target architecture.
4712 See the "Target Description Format" section in the user manual for
4715 * Multi-architecture debugging.
4717 GDB now includes general supports for debugging applications on
4718 hybrid systems that use more than one single processor architecture
4719 at the same time. Each such hybrid architecture still requires
4720 specific support to be added. The only hybrid architecture supported
4721 in this version of GDB is the Cell Broadband Engine.
4723 * GDB now supports integrated debugging of Cell/B.E. applications that
4724 use both the PPU and SPU architectures. To enable support for hybrid
4725 Cell/B.E. debugging, you need to configure GDB to support both the
4726 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
4727 --enable-targets configure option.
4729 * Non-stop mode debugging.
4731 For some targets, GDB now supports an optional mode of operation in
4732 which you can examine stopped threads while other threads continue
4733 to execute freely. This is referred to as non-stop mode, with the
4734 old mode referred to as all-stop mode. See the "Non-Stop Mode"
4735 section in the user manual for more information.
4737 To be able to support remote non-stop debugging, a remote stub needs
4738 to implement the non-stop mode remote protocol extensions, as
4739 described in the "Remote Non-Stop" section of the user manual. The
4740 GDB remote stub, gdbserver, has been adjusted to support these
4741 extensions on linux targets.
4743 * New commands (for set/show, see "New options" below)
4745 catch syscall [NAME(S) | NUMBER(S)]
4746 Catch system calls. Arguments, which should be names of system
4747 calls or their numbers, mean catch only those syscalls. Without
4748 arguments, every syscall will be caught. When the inferior issues
4749 any of the specified syscalls, GDB will stop and announce the system
4750 call, both when it is called and when its call returns. This
4751 feature is currently available with a native GDB running on the
4752 Linux Kernel, under the following architectures: x86, x86_64,
4753 PowerPC and PowerPC64.
4755 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
4757 Search memory for a sequence of bytes.
4759 maint set python print-stack
4760 maint show python print-stack
4761 Show a stack trace when an error is encountered in a Python script.
4764 Invoke CODE by passing it to the Python interpreter.
4769 These allow macros to be defined, undefined, and listed
4773 Show operating system information about processes.
4776 List the inferiors currently under GDB's control.
4779 Switch focus to inferior number NUM.
4782 Detach from inferior number NUM.
4785 Kill inferior number NUM.
4789 set spu stop-on-load
4790 show spu stop-on-load
4791 Control whether to stop for new SPE threads during Cell/B.E. debugging.
4793 set spu auto-flush-cache
4794 show spu auto-flush-cache
4795 Control whether to automatically flush the software-managed cache
4796 during Cell/B.E. debugging.
4798 set sh calling-convention
4799 show sh calling-convention
4800 Control the calling convention used when calling SH target functions.
4803 show debug timestamp
4804 Control display of timestamps with GDB debugging output.
4806 set disassemble-next-line
4807 show disassemble-next-line
4808 Control display of disassembled source lines or instructions when
4811 set remote noack-packet
4812 show remote noack-packet
4813 Set/show the use of remote protocol QStartNoAckMode packet. See above
4814 under "New remote packets."
4816 set remote query-attached-packet
4817 show remote query-attached-packet
4818 Control use of remote protocol `qAttached' (query-attached) packet.
4820 set remote read-siginfo-object
4821 show remote read-siginfo-object
4822 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4825 set remote write-siginfo-object
4826 show remote write-siginfo-object
4827 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4830 set remote reverse-continue
4831 show remote reverse-continue
4832 Control use of remote protocol 'bc' (reverse-continue) packet.
4834 set remote reverse-step
4835 show remote reverse-step
4836 Control use of remote protocol 'bs' (reverse-step) packet.
4838 set displaced-stepping
4839 show displaced-stepping
4840 Control displaced stepping mode. Displaced stepping is a way to
4841 single-step over breakpoints without removing them from the debuggee.
4842 Also known as "out-of-line single-stepping".
4845 show debug displaced
4846 Control display of debugging info for displaced stepping.
4848 maint set internal-error
4849 maint show internal-error
4850 Control what GDB does when an internal error is detected.
4852 maint set internal-warning
4853 maint show internal-warning
4854 Control what GDB does when an internal warning is detected.
4859 Use a wrapper program to launch programs for debugging.
4861 set multiple-symbols (all|ask|cancel)
4862 show multiple-symbols
4863 The value of this variable can be changed to adjust the debugger behavior
4864 when an expression or a breakpoint location contains an ambiguous symbol
4865 name (an overloaded function name, for instance).
4867 set breakpoint always-inserted
4868 show breakpoint always-inserted
4869 Keep breakpoints always inserted in the target, as opposed to inserting
4870 them when resuming the target, and removing them when the target stops.
4871 This option can improve debugger performance on slow remote targets.
4873 set arm fallback-mode (arm|thumb|auto)
4874 show arm fallback-mode
4875 set arm force-mode (arm|thumb|auto)
4877 These commands control how ARM GDB determines whether instructions
4878 are ARM or Thumb. The default for both settings is auto, which uses
4879 the current CPSR value for instructions without symbols; previous
4880 versions of GDB behaved as if "set arm fallback-mode arm".
4882 set disable-randomization
4883 show disable-randomization
4884 Standalone programs run with the virtual address space randomization enabled
4885 by default on some platforms. This option keeps the addresses stable across
4886 multiple debugging sessions.
4890 Control whether other threads are stopped or not when some thread hits
4895 Requests that asynchronous execution is enabled in the target, if available.
4896 In this case, it's possible to resume target in the background, and interact
4897 with GDB while the target is running. "show target-async" displays the
4898 current state of asynchronous execution of the target.
4900 set target-wide-charset
4901 show target-wide-charset
4902 The target-wide-charset is the name of the character set that GDB
4903 uses when printing characters whose type is wchar_t.
4905 set tcp auto-retry (on|off)
4907 set tcp connect-timeout
4908 show tcp connect-timeout
4909 These commands allow GDB to retry failed TCP connections to a remote stub
4910 with a specified timeout period; this is useful if the stub is launched
4911 in parallel with GDB but may not be ready to accept connections immediately.
4913 set libthread-db-search-path
4914 show libthread-db-search-path
4915 Control list of directories which GDB will search for appropriate
4918 set schedule-multiple (on|off)
4919 show schedule-multiple
4920 Allow GDB to resume all threads of all processes or only threads of
4921 the current process.
4925 Use more aggressive caching for accesses to the stack. This improves
4926 performance of remote debugging (particularly backtraces) without
4927 affecting correctness.
4929 set interactive-mode (on|off|auto)
4930 show interactive-mode
4931 Control whether GDB runs in interactive mode (on) or not (off).
4932 When in interactive mode, GDB waits for the user to answer all
4933 queries. Otherwise, GDB does not wait and assumes the default
4934 answer. When set to auto (the default), GDB determines which
4935 mode to use based on the stdin settings.
4940 For program forks, this is replaced by the new more generic `info
4941 inferiors' command. To list checkpoints, you can still use the
4942 `info checkpoints' command, which was an alias for the `info forks'
4946 Replaced by the new `inferior' command. To switch between
4947 checkpoints, you can still use the `restart' command, which was an
4948 alias for the `fork' command.
4951 This is removed, since some targets don't have a notion of
4952 processes. To switch between processes, you can still use the
4953 `inferior' command using GDB's own inferior number.
4956 For program forks, this is replaced by the new more generic `kill
4957 inferior' command. To delete a checkpoint, you can still use the
4958 `delete checkpoint' command, which was an alias for the `delete
4962 For program forks, this is replaced by the new more generic `detach
4963 inferior' command. To detach a checkpoint, you can still use the
4964 `detach checkpoint' command, which was an alias for the `detach
4967 * New native configurations
4969 x86/x86_64 Darwin i[34567]86-*-darwin*
4971 x86_64 MinGW x86_64-*-mingw*
4975 Lattice Mico32 lm32-*
4976 x86 DICOS i[34567]86-*-dicos*
4977 x86_64 DICOS x86_64-*-dicos*
4980 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4981 (mingw32ce) debugging.
4987 These commands were actually not implemented on any target.
4989 *** Changes in GDB 6.8
4991 * New native configurations
4993 NetBSD/hppa hppa*-*netbsd*
4994 Xtensa GNU/Linux xtensa*-*-linux*
4998 NetBSD/hppa hppa*-*-netbsd*
4999 Xtensa GNU/Linux xtensa*-*-linux*
5001 * Change in command line behavior -- corefiles vs. process ids.
5003 When the '-p NUMBER' or '--pid NUMBER' options are used, and
5004 attaching to process NUMBER fails, GDB no longer attempts to open a
5005 core file named NUMBER. Attaching to a program using the -c option
5006 is no longer supported. Instead, use the '-p' or '--pid' options.
5008 * GDB can now be built as a native debugger for debugging Windows x86
5009 (mingw32) Portable Executable (PE) programs.
5011 * Pending breakpoints no longer change their number when their address
5014 * GDB now supports breakpoints with multiple locations,
5015 including breakpoints on C++ constructors, inside C++ templates,
5016 and in inlined functions.
5018 * GDB's ability to debug optimized code has been improved. GDB more
5019 accurately identifies function bodies and lexical blocks that occupy
5020 more than one contiguous range of addresses.
5022 * Target descriptions can now describe registers for PowerPC.
5024 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
5025 registers on PowerPC targets.
5027 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
5028 targets even when the libthread_db library is not available.
5030 * The GDB remote stub, gdbserver, now supports the new file transfer
5031 commands (remote put, remote get, and remote delete).
5033 * The GDB remote stub, gdbserver, now supports run and attach in
5034 extended-remote mode.
5036 * hppa*64*-*-hpux11* target broken
5037 The debugger is unable to start a program and fails with the following
5038 error: "Error trying to get information about dynamic linker".
5039 The gdb-6.7 release is also affected.
5041 * GDB now supports the --enable-targets= configure option to allow
5042 building a single GDB executable that supports multiple remote
5043 target architectures.
5045 * GDB now supports debugging C and C++ programs which use the
5046 Decimal Floating Point extension. In addition, the PowerPC target
5047 now has a set of pseudo-registers to inspect decimal float values
5048 stored in two consecutive float registers.
5050 * The -break-insert MI command can optionally create pending
5053 * Improved support for debugging Ada
5054 Many improvements to the Ada language support have been made. These
5056 - Better support for Ada2005 interface types
5057 - Improved handling of arrays and slices in general
5058 - Better support for Taft-amendment types
5059 - The '{type} ADDRESS' expression is now allowed on the left hand-side
5061 - Improved command completion in Ada
5064 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
5069 set print frame-arguments (all|scalars|none)
5070 show print frame-arguments
5071 The value of this variable can be changed to control which argument
5072 values should be printed by the debugger when displaying a frame.
5077 Transfer files to and from a remote target, and delete remote files.
5084 Transfer files to and from a remote target, and delete remote files.
5086 * New remote packets
5093 Open, close, read, write, and delete files on the remote system.
5096 Attach to an existing process on the remote system, in extended-remote
5100 Run a new process on the remote system, in extended-remote mode.
5102 *** Changes in GDB 6.7
5104 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
5105 bfd, libiberty and opcodes, as revealed by static analysis donated by
5106 Coverity, Inc. (http://scan.coverity.com).
5108 * When looking up multiply-defined global symbols, GDB will now prefer the
5109 symbol definition in the current shared library if it was built using the
5110 -Bsymbolic linker option.
5112 * When the Text User Interface (TUI) is not configured, GDB will now
5113 recognize the -tui command-line option and print a message that the TUI
5116 * The GDB remote stub, gdbserver, now has lower overhead for high
5117 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
5119 * GDB for MIPS targets now autodetects whether a remote target provides
5120 32-bit or 64-bit register values.
5122 * Support for C++ member pointers has been improved.
5124 * GDB now understands XML target descriptions, which specify the
5125 target's overall architecture. GDB can read a description from
5126 a local file or over the remote serial protocol.
5128 * Vectors of single-byte data use a new integer type which is not
5129 automatically displayed as character or string data.
5131 * The /s format now works with the print command. It displays
5132 arrays of single-byte integers and pointers to single-byte integers
5135 * Target descriptions can now describe target-specific registers,
5136 for architectures which have implemented the support (currently
5137 only ARM, M68K, and MIPS).
5139 * GDB and the GDB remote stub, gdbserver, now support the XScale
5142 * The GDB remote stub, gdbserver, has been updated to support
5143 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
5144 has been rewritten to use the standard GDB remote protocol.
5146 * GDB can now step into C++ functions which are called through thunks.
5148 * GDB for the Cell/B.E. SPU now supports overlay debugging.
5150 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
5151 layout. It also supports a TextSeg= and DataSeg= response when only
5152 segment base addresses (rather than offsets) are available.
5154 * The /i format now outputs any trailing branch delay slot instructions
5155 immediately following the last instruction within the count specified.
5157 * The GDB remote protocol "T" stop reply packet now supports a
5158 "library" response. Combined with the new "qXfer:libraries:read"
5159 packet, this response allows GDB to debug shared libraries on targets
5160 where the operating system manages the list of loaded libraries (e.g.
5161 Windows and SymbianOS).
5163 * The GDB remote stub, gdbserver, now supports dynamic link libraries
5164 (DLLs) on Windows and Windows CE targets.
5166 * GDB now supports a faster verification that a .debug file matches its binary
5167 according to its build-id signature, if the signature is present.
5173 Enable or disable hardware flow control (RTS/CTS) on the serial port
5174 when debugging using remote targets.
5176 set mem inaccessible-by-default
5177 show mem inaccessible-by-default
5178 If the target supplies a memory map, for instance via the remote
5179 protocol's "qXfer:memory-map:read" packet, setting this variable
5180 prevents GDB from accessing memory outside the memory map. This
5181 is useful for targets with memory mapped registers or which react
5182 badly to accesses of unmapped address space.
5184 set breakpoint auto-hw
5185 show breakpoint auto-hw
5186 If the target supplies a memory map, for instance via the remote
5187 protocol's "qXfer:memory-map:read" packet, setting this variable
5188 lets GDB use hardware breakpoints automatically for memory regions
5189 where it can not use software breakpoints. This covers both the
5190 "break" command and internal breakpoints used for other commands
5191 including "next" and "finish".
5194 catch exception unhandled
5195 Stop the program execution when Ada exceptions are raised.
5198 Stop the program execution when an Ada assertion failed.
5202 Set an alternate system root for target files. This is a more
5203 general version of "set solib-absolute-prefix", which is now
5204 an alias to "set sysroot".
5207 Provide extended SPU facility status information. This set of
5208 commands is available only when debugging the Cell/B.E. SPU
5211 * New native configurations
5213 OpenBSD/sh sh*-*openbsd*
5216 unset tdesc filename
5218 Use the specified local file as an XML target description, and do
5219 not query the target for its built-in description.
5223 OpenBSD/sh sh*-*-openbsd*
5224 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
5225 Toshiba Media Processor mep-elf
5227 * New remote packets
5230 Ignore the specified signals; pass them directly to the debugged program
5231 without stopping other threads or reporting them to GDB.
5233 qXfer:features:read:
5234 Read an XML target description from the target, which describes its
5239 Read or write contents of an spufs file on the target system. These
5240 packets are available only on the Cell/B.E. SPU architecture.
5242 qXfer:libraries:read:
5243 Report the loaded shared libraries. Combined with new "T" packet
5244 response, this packet allows GDB to debug shared libraries on
5245 targets where the operating system manages the list of loaded
5246 libraries (e.g. Windows and SymbianOS).
5250 Support for these obsolete configurations has been removed.
5258 i[34567]86-*-lynxos*
5259 i[34567]86-*-netware*
5260 i[34567]86-*-sco3.2v5*
5261 i[34567]86-*-sco3.2v4*
5263 i[34567]86-*-sysv4.2*
5266 i[34567]86-*-unixware2*
5267 i[34567]86-*-unixware*
5276 * Other removed features
5283 Various m68k-only ROM monitors.
5290 Various Renesas ROM monitors and debugging interfaces for SH and
5295 Support for a Macraigor serial interface to on-chip debugging.
5296 GDB does not directly support the newer parallel or USB
5301 A debug information format. The predecessor to DWARF 2 and
5302 DWARF 3, which are still supported.
5304 Support for the HP aCC compiler on HP-UX/PA-RISC
5306 SOM-encapsulated symbolic debugging information, automatic
5307 invocation of pxdb, and the aCC custom C++ ABI. This does not
5308 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
5309 with aCC can still be debugged on an assembly level.
5311 MIPS ".pdr" sections
5313 A MIPS-specific format used to describe stack frame layout
5314 in debugging information.
5318 GDB could work with an older version of Guile to debug
5319 the interpreter and Scheme programs running in it.
5321 set mips stack-arg-size
5322 set mips saved-gpreg-size
5324 Use "set mips abi" to control parameter passing for MIPS.
5326 *** Changes in GDB 6.6
5331 Cell Broadband Engine SPU spu-elf
5333 * GDB can now be configured as a cross-debugger targeting native Windows
5334 (mingw32) or Cygwin. It can communicate with a remote debugging stub
5335 running on a Windows system over TCP/IP to debug Windows programs.
5337 * The GDB remote stub, gdbserver, has been updated to support Windows and
5338 Cygwin debugging. Both single-threaded and multi-threaded programs are
5341 * The "set trust-readonly-sections" command works again. This command was
5342 broken in GDB 6.3, 6.4, and 6.5.
5344 * The "load" command now supports writing to flash memory, if the remote
5345 stub provides the required support.
5347 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
5348 longer requires symbolic debug information (e.g. DWARF-2).
5353 unset substitute-path
5354 show substitute-path
5355 Manage a list of substitution rules that GDB uses to rewrite the name
5356 of the directories where the sources are located. This can be useful
5357 for instance when the sources were moved to a different location
5358 between compilation and debugging.
5362 Print each CLI command as it is executed. Each command is prefixed with
5363 a number of `+' symbols representing the nesting depth.
5364 The source command now has a `-v' option to enable the same feature.
5368 The ARM Demon monitor support (RDP protocol, "target rdp").
5370 Kernel Object Display, an embedded debugging feature which only worked with
5371 an obsolete version of Cisco IOS.
5373 The 'set download-write-size' and 'show download-write-size' commands.
5375 * New remote packets
5378 Tell a stub about GDB client features, and request remote target features.
5379 The first feature implemented is PacketSize, which allows the target to
5380 specify the size of packets it can handle - to minimize the number of
5381 packets required and improve performance when connected to a remote
5385 Fetch an OS auxilliary vector from the remote stub. This packet is a
5386 more efficient replacement for qPart:auxv:read.
5388 qXfer:memory-map:read:
5389 Fetch a memory map from the remote stub, including information about
5390 RAM, ROM, and flash memory devices.
5395 Erase and program a flash memory device.
5397 * Removed remote packets
5400 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
5401 used it, and only gdbserver implemented it.
5403 *** Changes in GDB 6.5
5407 Renesas M32C/M16C m32c-elf
5409 Morpho Technologies ms1 ms1-elf
5413 init-if-undefined Initialize a convenience variable, but
5414 only if it doesn't already have a value.
5416 The following commands are presently only implemented for native GNU/Linux:
5418 checkpoint Save a snapshot of the program state.
5420 restart <n> Return the program state to a
5421 previously saved state.
5423 info checkpoints List currently saved checkpoints.
5425 delete-checkpoint <n> Delete a previously saved checkpoint.
5427 set|show detach-on-fork Tell gdb whether to detach from a newly
5428 forked process, or to keep debugging it.
5430 info forks List forks of the user program that
5431 are available to be debugged.
5433 fork <n> Switch to debugging one of several
5434 forks of the user program that are
5435 available to be debugged.
5437 delete-fork <n> Delete a fork from the list of forks
5438 that are available to be debugged (and
5439 kill the forked process).
5441 detach-fork <n> Delete a fork from the list of forks
5442 that are available to be debugged (and
5443 allow the process to continue).
5447 Morpho Technologies ms2 ms1-elf
5449 * Improved Windows host support
5451 GDB now builds as a cross debugger hosted on i686-mingw32, including
5452 native console support, and remote communications using either
5453 network sockets or serial ports.
5455 * Improved Modula-2 language support
5457 GDB can now print most types in the Modula-2 syntax. This includes:
5458 basic types, set types, record types, enumerated types, range types,
5459 pointer types and ARRAY types. Procedure var parameters are correctly
5460 printed and hexadecimal addresses and character constants are also
5461 written in the Modula-2 syntax. Best results can be obtained by using
5462 GNU Modula-2 together with the -gdwarf-2 command line option.
5466 The ARM rdi-share module.
5468 The Netware NLM debug server.
5470 *** Changes in GDB 6.4
5472 * New native configurations
5474 OpenBSD/arm arm*-*-openbsd*
5475 OpenBSD/mips64 mips64-*-openbsd*
5479 Morpho Technologies ms1 ms1-elf
5481 * New command line options
5483 --batch-silent As for --batch, but totally silent.
5484 --return-child-result The debugger will exist with the same value
5485 the child (debugged) program exited with.
5486 --eval-command COMMAND, -ex COMMAND
5487 Execute a single GDB CLI command. This may be
5488 specified multiple times and in conjunction
5489 with the --command (-x) option.
5491 * Deprecated commands removed
5493 The following commands, that were deprecated in 2000, have been
5497 set|show arm disassembly-flavor set|show arm disassembler
5498 othernames set arm disassembler
5499 set|show remotedebug set|show debug remote
5500 set|show archdebug set|show debug arch
5501 set|show eventdebug set|show debug event
5504 * New BSD user-level threads support
5506 It is now possible to debug programs using the user-level threads
5507 library on OpenBSD and FreeBSD. Currently supported (target)
5510 FreeBSD/amd64 x86_64-*-freebsd*
5511 FreeBSD/i386 i386-*-freebsd*
5512 OpenBSD/i386 i386-*-openbsd*
5514 Note that the new kernel threads libraries introduced in FreeBSD 5.x
5515 are not yet supported.
5517 * New support for Matsushita MN10300 w/sim added
5518 (Work in progress). mn10300-elf.
5520 * REMOVED configurations and files
5522 VxWorks and the XDR protocol *-*-vxworks
5523 Motorola MCORE mcore-*-*
5524 National Semiconductor NS32000 ns32k-*-*
5526 * New "set print array-indexes" command
5528 After turning this setting "on", GDB prints the index of each element
5529 when displaying arrays. The default is "off" to preserve the previous
5532 * VAX floating point support
5534 GDB now supports the not-quite-ieee VAX F and D floating point formats.
5536 * User-defined command support
5538 In addition to using $arg0..$arg9 for argument passing, it is now possible
5539 to use $argc to determine now many arguments have been passed. See the
5540 section on user-defined commands in the user manual for more information.
5542 *** Changes in GDB 6.3:
5544 * New command line option
5546 GDB now accepts -l followed by a number to set the timeout for remote
5549 * GDB works with GCC -feliminate-dwarf2-dups
5551 GDB now supports a more compact representation of DWARF-2 debug
5552 information using DW_FORM_ref_addr references. These are produced
5553 by GCC with the option -feliminate-dwarf2-dups and also by some
5554 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
5555 to use -feliminate-dwarf2-dups.
5557 * Internationalization
5559 When supported by the host system, GDB will be built with
5560 internationalization (libintl). The task of marking up the sources is
5561 continued, we're looking forward to our first translation.
5565 Initial support for debugging programs compiled with the GNAT
5566 implementation of the Ada programming language has been integrated
5567 into GDB. In this release, support is limited to expression evaluation.
5569 * New native configurations
5571 GNU/Linux/m32r m32r-*-linux-gnu
5575 GDB's remote protocol now includes support for the 'p' packet. This
5576 packet is used to fetch individual registers from a remote inferior.
5578 * END-OF-LIFE registers[] compatibility module
5580 GDB's internal register infrastructure has been completely rewritten.
5581 The new infrastructure making possible the implementation of key new
5582 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
5585 GDB 6.3 will be the last release to include the registers[]
5586 compatibility module that allowed out-of-date configurations to
5587 continue to work. This change directly impacts the following
5597 powerpc bdm protocol
5599 Unless there is activity to revive these configurations, they will be
5600 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
5602 * OBSOLETE configurations and files
5604 Configurations that have been declared obsolete in this release have
5605 been commented out. Unless there is activity to revive these
5606 configurations, the next release of GDB will have their sources
5607 permanently REMOVED.
5616 *** Changes in GDB 6.2.1:
5618 * MIPS `break main; run' gave an heuristic-fence-post warning
5620 When attempting to run even a simple program, a warning about
5621 heuristic-fence-post being hit would be reported. This problem has
5624 * MIPS IRIX 'long double' crashed GDB
5626 When examining a long double variable, GDB would get a segmentation
5627 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
5628 IRIX long double values).
5632 A bug in the VAX stack code was causing problems with the "next"
5633 command. This problem has been fixed.
5635 *** Changes in GDB 6.2:
5637 * Fix for ``many threads''
5639 On GNU/Linux systems that use the NPTL threads library, a program
5640 rapidly creating and deleting threads would confuse GDB leading to the
5643 ptrace: No such process.
5644 thread_db_get_info: cannot get thread info: generic error
5646 This problem has been fixed.
5648 * "-async" and "-noasync" options removed.
5650 Support for the broken "-noasync" option has been removed (it caused
5653 * New ``start'' command.
5655 This command runs the program until the beginning of the main procedure.
5657 * New BSD Kernel Data Access Library (libkvm) interface
5659 Using ``target kvm'' it is now possible to debug kernel core dumps and
5660 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
5661 platforms. Currently supported (native-only) configurations are:
5663 FreeBSD/amd64 x86_64-*-freebsd*
5664 FreeBSD/i386 i?86-*-freebsd*
5665 NetBSD/i386 i?86-*-netbsd*
5666 NetBSD/m68k m68*-*-netbsd*
5667 NetBSD/sparc sparc-*-netbsd*
5668 OpenBSD/amd64 x86_64-*-openbsd*
5669 OpenBSD/i386 i?86-*-openbsd*
5670 OpenBSD/m68k m68*-openbsd*
5671 OpenBSD/sparc sparc-*-openbsd*
5673 * Signal trampoline code overhauled
5675 Many generic problems with GDB's signal handling code have been fixed.
5676 These include: backtraces through non-contiguous stacks; recognition
5677 of sa_sigaction signal trampolines; backtrace from a NULL pointer
5678 call; backtrace through a signal trampoline; step into and out of
5679 signal handlers; and single-stepping in the signal trampoline.
5681 Please note that kernel bugs are a limiting factor here. These
5682 features have been shown to work on an s390 GNU/Linux system that
5683 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
5685 * Cygwin support for DWARF 2 added.
5687 * New native configurations
5689 GNU/Linux/hppa hppa*-*-linux*
5690 OpenBSD/hppa hppa*-*-openbsd*
5691 OpenBSD/m68k m68*-*-openbsd*
5692 OpenBSD/m88k m88*-*-openbsd*
5693 OpenBSD/powerpc powerpc-*-openbsd*
5694 NetBSD/vax vax-*-netbsd*
5695 OpenBSD/vax vax-*-openbsd*
5697 * END-OF-LIFE frame compatibility module
5699 GDB's internal frame infrastructure has been completely rewritten.
5700 The new infrastructure making it possible to support key new features
5701 including DWARF 2 Call Frame Information. To aid in the task of
5702 migrating old configurations to this new infrastructure, a
5703 compatibility module, that allowed old configurations to continue to
5704 work, was also included.
5706 GDB 6.2 will be the last release to include this frame compatibility
5707 module. This change directly impacts the following configurations:
5717 Unless there is activity to revive these configurations, they will be
5718 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
5720 * REMOVED configurations and files
5722 Sun 3, running SunOS 3 m68*-*-sunos3*
5723 Sun 3, running SunOS 4 m68*-*-sunos4*
5724 Sun 2, running SunOS 3 m68000-*-sunos3*
5725 Sun 2, running SunOS 4 m68000-*-sunos4*
5726 Motorola 680x0 running LynxOS m68*-*-lynxos*
5727 AT&T 3b1/Unix pc m68*-att-*
5728 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5729 decstation mips-dec-* mips-little-*
5730 riscos mips-*-riscos* mips-*-sysv*
5731 sonymips mips-sony-*
5732 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5734 *** Changes in GDB 6.1.1:
5736 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
5738 The TUI (Text-mode User Interface) is now built as part of a default
5739 GDB configuration. It is enabled by either selecting the TUI with the
5740 command line option "-i=tui" or by running the separate "gdbtui"
5741 program. For more information on the TUI, see the manual "Debugging
5744 * Pending breakpoint support (also included in GDB 6.1)
5746 Support has been added to allow you to specify breakpoints in shared
5747 libraries that have not yet been loaded. If a breakpoint location
5748 cannot be found, and the "breakpoint pending" option is set to auto,
5749 GDB queries you if you wish to make the breakpoint pending on a future
5750 shared-library load. If and when GDB resolves the breakpoint symbol,
5751 the pending breakpoint is removed as one or more regular breakpoints
5754 Pending breakpoints are very useful for GCJ Java debugging.
5756 * Fixed ISO-C build problems
5758 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
5759 non ISO-C code that stopped them being built using a more strict ISO-C
5760 compiler (e.g., IBM's C compiler).
5762 * Fixed build problem on IRIX 5
5764 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
5765 wasn't able to compile compile on an IRIX 5 system.
5767 * Added execute permission to gdb/gdbserver/configure
5769 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
5770 permission. This bug would cause configure to fail on a number of
5771 systems (Solaris, IRIX). Ref: server/519.
5773 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
5775 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
5776 has been updated to use constant array sizes.
5778 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
5780 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
5781 its generated DWARF Call Frame Info. This encoding was causing GDB to
5782 panic, that panic has been fixed. Ref: gdb/1628.
5784 * Fixed a problem when examining parameters in shared library code.
5786 When examining parameters in optimized shared library code generated
5787 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
5788 not available''. GDB now correctly displays the variable's value.
5790 *** Changes in GDB 6.1:
5792 * Removed --with-mmalloc
5794 Support for the mmalloc memory manager has been removed, as it
5795 conflicted with the internal gdb byte cache.
5797 * Changes in AMD64 configurations
5799 The AMD64 target now includes the %cs and %ss registers. As a result
5800 the AMD64 remote protocol has changed; this affects the floating-point
5801 and SSE registers. If you rely on those registers for your debugging,
5802 you should upgrade gdbserver on the remote side.
5804 * Revised SPARC target
5806 The SPARC target has been completely revised, incorporating the
5807 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
5808 support for LynxOS and SunOS 4 has been dropped. Calling functions
5809 from within GDB on operating systems with a non-executable stack
5810 (Solaris, OpenBSD) now works.
5814 GDB has a new C++ demangler which does a better job on the mangled
5815 names generated by current versions of g++. It also runs faster, so
5816 with this and other changes gdb should now start faster on large C++
5819 * DWARF 2 Location Expressions
5821 GDB support for location expressions has been extended to support function
5822 arguments and frame bases. Older versions of GDB could crash when they
5825 * C++ nested types and namespaces
5827 GDB's support for nested types and namespaces in C++ has been
5828 improved, especially if you use the DWARF 2 debugging format. (This
5829 is the default for recent versions of GCC on most platforms.)
5830 Specifically, if you have a class "Inner" defined within a class or
5831 namespace "Outer", then GDB realizes that the class's name is
5832 "Outer::Inner", not simply "Inner". This should greatly reduce the
5833 frequency of complaints about not finding RTTI symbols. In addition,
5834 if you are stopped at inside of a function defined within a namespace,
5835 GDB modifies its name lookup accordingly.
5837 * New native configurations
5839 NetBSD/amd64 x86_64-*-netbsd*
5840 OpenBSD/amd64 x86_64-*-openbsd*
5841 OpenBSD/alpha alpha*-*-openbsd*
5842 OpenBSD/sparc sparc-*-openbsd*
5843 OpenBSD/sparc64 sparc64-*-openbsd*
5845 * New debugging protocols
5847 M32R with SDI protocol m32r-*-elf*
5849 * "set prompt-escape-char" command deleted.
5851 The command "set prompt-escape-char" has been deleted. This command,
5852 and its very obscure effect on GDB's prompt, was never documented,
5853 tested, nor mentioned in the NEWS file.
5855 * OBSOLETE configurations and files
5857 Configurations that have been declared obsolete in this release have
5858 been commented out. Unless there is activity to revive these
5859 configurations, the next release of GDB will have their sources
5860 permanently REMOVED.
5862 Sun 3, running SunOS 3 m68*-*-sunos3*
5863 Sun 3, running SunOS 4 m68*-*-sunos4*
5864 Sun 2, running SunOS 3 m68000-*-sunos3*
5865 Sun 2, running SunOS 4 m68000-*-sunos4*
5866 Motorola 680x0 running LynxOS m68*-*-lynxos*
5867 AT&T 3b1/Unix pc m68*-att-*
5868 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5869 decstation mips-dec-* mips-little-*
5870 riscos mips-*-riscos* mips-*-sysv*
5871 sonymips mips-sony-*
5872 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5874 * REMOVED configurations and files
5876 SGI Irix-4.x mips-sgi-irix4 or iris4
5877 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5878 Z8000 simulator z8k-zilog-none or z8ksim
5879 Matsushita MN10200 w/simulator mn10200-*-*
5880 H8/500 simulator h8500-hitachi-hms or h8500hms
5881 HP/PA running BSD hppa*-*-bsd*
5882 HP/PA running OSF/1 hppa*-*-osf*
5883 HP/PA Pro target hppa*-*-pro*
5884 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5885 386BSD i[3456]86-*-bsd*
5886 Sequent family i[3456]86-sequent-sysv4*
5887 i[3456]86-sequent-sysv*
5888 i[3456]86-sequent-bsd*
5889 SPARC running LynxOS sparc-*-lynxos*
5890 SPARC running SunOS 4 sparc-*-sunos4*
5891 Tsqware Sparclet sparclet-*-*
5892 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5894 *** Changes in GDB 6.0:
5898 Support for debugging the Objective-C programming language has been
5899 integrated into GDB.
5901 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5903 DWARF 2's Call Frame Information makes available compiler generated
5904 information that more exactly describes the program's run-time stack.
5905 By using this information, GDB is able to provide more robust stack
5908 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5909 have been updated to use a new backtrace mechanism which includes
5910 DWARF 2 CFI support.
5914 GDB's remote protocol has been extended to include support for hosted
5915 file I/O (where the remote target uses GDB's file system). See GDB's
5916 remote protocol documentation for details.
5918 * All targets using the new architecture framework.
5920 All of GDB's targets have been updated to use the new internal
5921 architecture framework. The way is now open for future GDB releases
5922 to include cross-architecture native debugging support (i386 on amd64,
5925 * GNU/Linux's Thread Local Storage (TLS)
5927 GDB now includes support for for the GNU/Linux implementation of
5928 per-thread variables.
5930 * GNU/Linux's Native POSIX Thread Library (NPTL)
5932 GDB's thread code has been updated to work with either the new
5933 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5935 * Separate debug info.
5937 GDB, in conjunction with BINUTILS, now supports a mechanism for
5938 automatically loading debug information from a separate file. Instead
5939 of shipping full debug and non-debug versions of system libraries,
5940 system integrators can now instead ship just the stripped libraries
5941 and optional debug files.
5943 * DWARF 2 Location Expressions
5945 DWARF 2 Location Expressions allow the compiler to more completely
5946 describe the location of variables (even in optimized code) to the
5949 GDB now includes preliminary support for location expressions (support
5950 for DW_OP_piece is still missing).
5954 A number of long standing bugs that caused GDB to die while starting a
5955 Java application have been fixed. GDB's Java support is now
5956 considered "useable".
5958 * GNU/Linux support for fork, vfork, and exec.
5960 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5961 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5964 * GDB supports logging output to a file
5966 There are two new commands, "set logging" and "show logging", which can be
5967 used to capture GDB's output to a file.
5969 * The meaning of "detach" has changed for gdbserver
5971 The "detach" command will now resume the application, as documented. To
5972 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5975 * d10v, m68hc11 `regs' command deprecated
5977 The `info registers' command has been updated so that it displays the
5978 registers using a format identical to the old `regs' command.
5982 A new command, "maint set profile on/off", has been added. This command can
5983 be used to enable or disable profiling while running GDB, to profile a
5984 session or a set of commands. In addition there is a new configure switch,
5985 "--enable-profiling", which will cause GDB to be compiled with profiling
5986 data, for more informative profiling results.
5988 * Default MI syntax changed to "mi2".
5990 The default MI (machine interface) syntax, enabled by the command line
5991 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5992 "mi1", can be enabled by specifying the option "-i=mi1".
5994 Support for the original "mi0" syntax (included in GDB 5.0) has been
5997 Fix for gdb/192: removed extraneous space when displaying frame level.
5998 Fix for gdb/672: update changelist is now output in mi list format.
5999 Fix for gdb/702: a -var-assign that updates the value now shows up
6000 in a subsequent -var-update.
6002 * New native configurations.
6004 FreeBSD/amd64 x86_64-*-freebsd*
6006 * Multi-arched targets.
6008 HP/PA HPUX11 hppa*-*-hpux*
6009 Renesas M32R/D w/simulator m32r-*-elf*
6011 * OBSOLETE configurations and files
6013 Configurations that have been declared obsolete in this release have
6014 been commented out. Unless there is activity to revive these
6015 configurations, the next release of GDB will have their sources
6016 permanently REMOVED.
6018 Z8000 simulator z8k-zilog-none or z8ksim
6019 Matsushita MN10200 w/simulator mn10200-*-*
6020 H8/500 simulator h8500-hitachi-hms or h8500hms
6021 HP/PA running BSD hppa*-*-bsd*
6022 HP/PA running OSF/1 hppa*-*-osf*
6023 HP/PA Pro target hppa*-*-pro*
6024 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
6025 Sequent family i[3456]86-sequent-sysv4*
6026 i[3456]86-sequent-sysv*
6027 i[3456]86-sequent-bsd*
6028 Tsqware Sparclet sparclet-*-*
6029 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6031 * REMOVED configurations and files
6034 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6035 IBM AIX PS/2 i[3456]86-*-aix
6036 i386 running Mach 3.0 i[3456]86-*-mach3*
6037 i386 running Mach i[3456]86-*-mach*
6038 i386 running OSF/1 i[3456]86-*osf1mk*
6039 HP/Apollo 68k Family m68*-apollo*-sysv*,
6041 m68*-hp-bsd*, m68*-hp-hpux*
6042 Argonaut Risc Chip (ARC) arc-*-*
6043 Mitsubishi D30V d30v-*-*
6044 Fujitsu FR30 fr30-*-elf*
6045 OS/9000 i[34]86-*-os9k
6046 I960 with MON960 i960-*-coff
6048 * MIPS $fp behavior changed
6050 The convenience variable $fp, for the MIPS, now consistently returns
6051 the address of the current frame's base. Previously, depending on the
6052 context, $fp could refer to either $sp or the current frame's base
6053 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
6054 The GNU Source-Level Debugger''.
6056 *** Changes in GDB 5.3:
6058 * GNU/Linux shared library multi-threaded performance improved.
6060 When debugging a multi-threaded application on GNU/Linux, GDB now uses
6061 `/proc', in preference to `ptrace' for memory reads. This may result
6062 in an improvement in the start-up time of multi-threaded, shared
6063 library applications when run under GDB. One GDB user writes: ``loads
6064 shared libs like mad''.
6066 * ``gdbserver'' now supports multi-threaded applications on some targets
6068 Support for debugging multi-threaded applications which use
6069 the GNU/Linux LinuxThreads package has been added for
6070 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
6071 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
6073 * GDB now supports C/C++ preprocessor macros.
6075 GDB now expands preprocessor macro invocations in C/C++ expressions,
6076 and provides various commands for showing macro definitions and how
6079 The new command `macro expand EXPRESSION' expands any macro
6080 invocations in expression, and shows the result.
6082 The new command `show macro MACRO-NAME' shows the definition of the
6083 macro named MACRO-NAME, and where it was defined.
6085 Most compilers don't include information about macros in the debugging
6086 information by default. In GCC 3.1, for example, you need to compile
6087 your program with the options `-gdwarf-2 -g3'. If the macro
6088 information is present in the executable, GDB will read it.
6090 * Multi-arched targets.
6092 DEC Alpha (partial) alpha*-*-*
6093 DEC VAX (partial) vax-*-*
6095 National Semiconductor NS32000 (partial) ns32k-*-*
6096 Motorola 68000 (partial) m68k-*-*
6097 Motorola MCORE mcore-*-*
6101 Fujitsu FRV architecture added by Red Hat frv*-*-*
6104 * New native configurations
6106 Alpha NetBSD alpha*-*-netbsd*
6107 SH NetBSD sh*-*-netbsdelf*
6108 MIPS NetBSD mips*-*-netbsd*
6109 UltraSPARC NetBSD sparc64-*-netbsd*
6111 * OBSOLETE configurations and files
6113 Configurations that have been declared obsolete in this release have
6114 been commented out. Unless there is activity to revive these
6115 configurations, the next release of GDB will have their sources
6116 permanently REMOVED.
6118 Mitsubishi D30V d30v-*-*
6119 OS/9000 i[34]86-*-os9k
6120 IBM AIX PS/2 i[3456]86-*-aix
6121 Fujitsu FR30 fr30-*-elf*
6122 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6123 Argonaut Risc Chip (ARC) arc-*-*
6124 i386 running Mach 3.0 i[3456]86-*-mach3*
6125 i386 running Mach i[3456]86-*-mach*
6126 i386 running OSF/1 i[3456]86-*osf1mk*
6127 HP/Apollo 68k Family m68*-apollo*-sysv*,
6129 m68*-hp-bsd*, m68*-hp-hpux*
6130 I960 with MON960 i960-*-coff
6132 * OBSOLETE languages
6134 CHILL, a Pascal like language used by telecommunications companies.
6136 * REMOVED configurations and files
6138 AMD 29k family via UDI a29k-amd-udi, udi29k
6139 A29K VxWorks a29k-*-vxworks
6140 AMD 29000 embedded, using EBMON a29k-none-none
6141 AMD 29000 embedded with COFF a29k-none-coff
6142 AMD 29000 embedded with a.out a29k-none-aout
6144 testsuite/gdb.hp/gdb.threads-hp/ directory
6146 * New command "set max-user-call-depth <nnn>"
6148 This command allows the user to limit the call depth of user-defined
6149 commands. The default is 1024.
6151 * Changes in FreeBSD/i386 native debugging.
6153 Support for the "generate-core-file" has been added.
6155 * New commands "dump", "append", and "restore".
6157 These commands allow data to be copied from target memory
6158 to a bfd-format or binary file (dump and append), and back
6159 from a file into memory (restore).
6161 * Improved "next/step" support on multi-processor Alpha Tru64.
6163 The previous single-step mechanism could cause unpredictable problems,
6164 including the random appearance of SIGSEGV or SIGTRAP signals. The use
6165 of a software single-step mechanism prevents this.
6167 *** Changes in GDB 5.2.1:
6175 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
6176 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
6177 Fix, by Joel Brobecker imported from mainline.
6179 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
6180 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
6181 Fix, by Fred Fish, imported from mainline.
6183 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
6184 Surprisingly enough, it works now.
6185 By Michal Ludvig, imported from mainline.
6187 i386 hardware watchpoint support:
6188 avoid misses on second run for some targets.
6189 By Pierre Muller, imported from mainline.
6191 *** Changes in GDB 5.2:
6193 * New command "set trust-readonly-sections on[off]".
6195 This command is a hint that tells gdb that read-only sections
6196 really are read-only (ie. that their contents will not change).
6197 In this mode, gdb will go to the object file rather than the
6198 target to read memory from read-only sections (such as ".text").
6199 This can be a significant performance improvement on some
6200 (notably embedded) targets.
6202 * New command "generate-core-file" (or "gcore").
6204 This new gdb command allows the user to drop a core file of the child
6205 process state at any time. So far it's been implemented only for
6206 GNU/Linux and Solaris, but should be relatively easily ported to other
6207 hosts. Argument is core file name (defaults to core.<pid>).
6209 * New command line option
6211 GDB now accepts --pid or -p followed by a process id.
6213 * Change in command line behavior -- corefiles vs. process ids.
6215 There is a subtle behavior in the way in which GDB handles
6216 command line arguments. The first non-flag argument is always
6217 a program to debug, but the second non-flag argument may either
6218 be a corefile or a process id. Previously, GDB would attempt to
6219 open the second argument as a corefile, and if that failed, would
6220 issue a superfluous error message and then attempt to attach it as
6221 a process. Now, if the second argument begins with a non-digit,
6222 it will be treated as a corefile. If it begins with a digit,
6223 GDB will attempt to attach it as a process, and if no such process
6224 is found, will then attempt to open it as a corefile.
6226 * Changes in ARM configurations.
6228 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
6229 configuration is fully multi-arch.
6231 * New native configurations
6233 ARM NetBSD arm*-*-netbsd*
6234 x86 OpenBSD i[3456]86-*-openbsd*
6235 AMD x86-64 running GNU/Linux x86_64-*-linux-*
6236 Sparc64 running FreeBSD sparc64-*-freebsd*
6240 Sanyo XStormy16 xstormy16-elf
6242 * OBSOLETE configurations and files
6244 Configurations that have been declared obsolete in this release have
6245 been commented out. Unless there is activity to revive these
6246 configurations, the next release of GDB will have their sources
6247 permanently REMOVED.
6249 AMD 29k family via UDI a29k-amd-udi, udi29k
6250 A29K VxWorks a29k-*-vxworks
6251 AMD 29000 embedded, using EBMON a29k-none-none
6252 AMD 29000 embedded with COFF a29k-none-coff
6253 AMD 29000 embedded with a.out a29k-none-aout
6255 testsuite/gdb.hp/gdb.threads-hp/ directory
6257 * REMOVED configurations and files
6259 TI TMS320C80 tic80-*-*
6261 PowerPC Solaris powerpcle-*-solaris*
6262 PowerPC Windows NT powerpcle-*-cygwin32
6263 PowerPC Netware powerpc-*-netware*
6264 Harris/CXUX m88k m88*-harris-cxux*
6265 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
6266 ns32k-utek-sysv* ns32k-utek-*
6267 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
6268 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
6269 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
6270 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
6271 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
6273 * Changes to command line processing
6275 The new `--args' feature can be used to specify command-line arguments
6276 for the inferior from gdb's command line.
6278 * Changes to key bindings
6280 There is a new `operate-and-get-next' function bound to `C-o'.
6282 *** Changes in GDB 5.1.1
6284 Fix compile problem on DJGPP.
6286 Fix a problem with floating-point registers on the i386 being
6289 Fix to stop GDB crashing on .debug_str debug info.
6291 Numerous documentation fixes.
6293 Numerous testsuite fixes.
6295 *** Changes in GDB 5.1:
6297 * New native configurations
6299 Alpha FreeBSD alpha*-*-freebsd*
6300 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
6301 MIPS GNU/Linux mips*-*-linux*
6302 MIPS SGI Irix 6.x mips*-sgi-irix6*
6303 ia64 AIX ia64-*-aix*
6304 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
6308 Motorola 68HC11 and 68HC12 m68hc11-elf
6310 UltraSparc running GNU/Linux sparc64-*-linux*
6312 * OBSOLETE configurations and files
6314 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
6315 Harris/CXUX m88k m88*-harris-cxux*
6316 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
6317 ns32k-utek-sysv* ns32k-utek-*
6318 TI TMS320C80 tic80-*-*
6320 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
6321 PowerPC Solaris powerpcle-*-solaris*
6322 PowerPC Windows NT powerpcle-*-cygwin32
6323 PowerPC Netware powerpc-*-netware*
6324 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
6325 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
6326 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
6327 Apple Macintosh (MPW) host N/A
6329 stuff.c (Program to stuff files into a specially prepared space in kdb)
6330 kdb-start.c (Main loop for the standalone kernel debugger)
6332 Configurations that have been declared obsolete in this release have
6333 been commented out. Unless there is activity to revive these
6334 configurations, the next release of GDB will have their sources
6335 permanently REMOVED.
6337 * REMOVED configurations and files
6339 Altos 3068 m68*-altos-*
6340 Convex c1-*-*, c2-*-*
6342 ARM RISCix arm-*-* (as host)
6346 * GDB has been converted to ISO C.
6348 GDB's source code has been converted to ISO C. In particular, the
6349 sources are fully protoized, and rely on standard headers being
6354 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
6356 * The MI enabled by default.
6358 The new machine oriented interface (MI) introduced in GDB 5.0 has been
6359 revised and enabled by default. Packages which use GDB as a debugging
6360 engine behind a UI or another front end are encouraged to switch to
6361 using the GDB/MI interface, instead of the old annotations interface
6362 which is now deprecated.
6364 * Support for debugging Pascal programs.
6366 GDB now includes support for debugging Pascal programs. The following
6367 main features are supported:
6369 - Pascal-specific data types such as sets;
6371 - automatic recognition of Pascal sources based on file-name
6374 - Pascal-style display of data types, variables, and functions;
6376 - a Pascal expression parser.
6378 However, some important features are not yet supported.
6380 - Pascal string operations are not supported at all;
6382 - there are some problems with boolean types;
6384 - Pascal type hexadecimal constants are not supported
6385 because they conflict with the internal variables format;
6387 - support for Pascal objects and classes is not full yet;
6389 - unlike Pascal, GDB is case-sensitive for symbol names.
6391 * Changes in completion.
6393 Commands such as `shell', `run' and `set args', which pass arguments
6394 to inferior programs, now complete on file names, similar to what
6395 users expect at the shell prompt.
6397 Commands which accept locations, such as `disassemble', `print',
6398 `breakpoint', `until', etc. now complete on filenames as well as
6399 program symbols. Thus, if you type "break foob TAB", and the source
6400 files linked into the programs include `foobar.c', that file name will
6401 be one of the candidates for completion. However, file names are not
6402 considered for completion after you typed a colon that delimits a file
6403 name from a name of a function in that file, as in "break foo.c:bar".
6405 `set demangle-style' completes on available demangling styles.
6407 * New platform-independent commands:
6409 It is now possible to define a post-hook for a command as well as a
6410 hook that runs before the command. For more details, see the
6411 documentation of `hookpost' in the GDB manual.
6413 * Changes in GNU/Linux native debugging.
6415 Support for debugging multi-threaded programs has been completely
6416 revised for all platforms except m68k and sparc. You can now debug as
6417 many threads as your system allows you to have.
6419 Attach/detach is supported for multi-threaded programs.
6421 Support for SSE registers was added for x86. This doesn't work for
6422 multi-threaded programs though.
6424 * Changes in MIPS configurations.
6426 Multi-arch support is enabled for all MIPS configurations.
6428 GDB can now be built as native debugger on SGI Irix 6.x systems for
6429 debugging n32 executables. (Debugging 64-bit executables is not yet
6432 * Unified support for hardware watchpoints in all x86 configurations.
6434 Most (if not all) native x86 configurations support hardware-assisted
6435 breakpoints and watchpoints in a unified manner. This support
6436 implements debug register sharing between watchpoints, which allows to
6437 put a virtually infinite number of watchpoints on the same address,
6438 and also supports watching regions up to 16 bytes with several debug
6441 The new maintenance command `maintenance show-debug-regs' toggles
6442 debugging print-outs in functions that insert, remove, and test
6443 watchpoints and hardware breakpoints.
6445 * Changes in the DJGPP native configuration.
6447 New command ``info dos sysinfo'' displays assorted information about
6448 the CPU, OS, memory, and DPMI server.
6450 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
6451 display information about segment descriptors stored in GDT, LDT, and
6454 New commands ``info dos pde'' and ``info dos pte'' display entries
6455 from Page Directory and Page Tables (for now works with CWSDPMI only).
6456 New command ``info dos address-pte'' displays the Page Table entry for
6457 a given linear address.
6459 GDB can now pass command lines longer than 126 characters to the
6460 program being debugged (requires an update to the libdbg.a library
6461 which is part of the DJGPP development kit).
6463 DWARF2 debug info is now supported.
6465 It is now possible to `step' and `next' through calls to `longjmp'.
6467 * Changes in documentation.
6469 All GDB documentation was converted to GFDL, the GNU Free
6470 Documentation License.
6472 Tracepoints-related commands are now fully documented in the GDB
6475 TUI, the Text-mode User Interface, is now documented in the manual.
6477 Tracepoints-related commands are now fully documented in the GDB
6480 The "GDB Internals" manual now has an index. It also includes
6481 documentation of `ui_out' functions, GDB coding standards, x86
6482 hardware watchpoints, and memory region attributes.
6484 * GDB's version number moved to ``version.in''
6486 The Makefile variable VERSION has been replaced by the file
6487 ``version.in''. People creating GDB distributions should update the
6488 contents of this file.
6492 GUD support is now a standard part of the EMACS distribution.
6494 *** Changes in GDB 5.0:
6496 * Improved support for debugging FP programs on x86 targets
6498 Unified and much-improved support for debugging floating-point
6499 programs on all x86 targets. In particular, ``info float'' now
6500 displays the FP registers in the same format on all x86 targets, with
6501 greater level of detail.
6503 * Improvements and bugfixes in hardware-assisted watchpoints
6505 It is now possible to watch array elements, struct members, and
6506 bitfields with hardware-assisted watchpoints. Data-read watchpoints
6507 on x86 targets no longer erroneously trigger when the address is
6510 * Improvements in the native DJGPP version of GDB
6512 The distribution now includes all the scripts and auxiliary files
6513 necessary to build the native DJGPP version on MS-DOS/MS-Windows
6514 machines ``out of the box''.
6516 The DJGPP version can now debug programs that use signals. It is
6517 possible to catch signals that happened in the debuggee, deliver
6518 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
6519 would kill the program being debugged.) Programs that hook hardware
6520 interrupts (keyboard, timer, etc.) can also be debugged.
6522 It is now possible to debug DJGPP programs that redirect their
6523 standard handles or switch them to raw (as opposed to cooked) mode, or
6524 even close them. The command ``run < foo > bar'' works as expected,
6525 and ``info terminal'' reports useful information about the debuggee's
6526 terminal, including raw/cooked mode, redirection, etc.
6528 The DJGPP version now uses termios functions for console I/O, which
6529 enables debugging graphics programs. Interrupting GDB with Ctrl-C
6532 DOS-style file names with drive letters are now fully supported by
6535 It is now possible to debug DJGPP programs that switch their working
6536 directory. It is also possible to rerun the debuggee any number of
6537 times without restarting GDB; thus, you can use the same setup,
6538 breakpoints, etc. for many debugging sessions.
6540 * New native configurations
6542 ARM GNU/Linux arm*-*-linux*
6543 PowerPC GNU/Linux powerpc-*-linux*
6547 Motorola MCore mcore-*-*
6548 x86 VxWorks i[3456]86-*-vxworks*
6549 PowerPC VxWorks powerpc-*-vxworks*
6550 TI TMS320C80 tic80-*-*
6552 * OBSOLETE configurations
6554 Altos 3068 m68*-altos-*
6555 Convex c1-*-*, c2-*-*
6557 ARM RISCix arm-*-* (as host)
6560 Configurations that have been declared obsolete will be commented out,
6561 but the code will be left in place. If there is no activity to revive
6562 these configurations before the next release of GDB, the sources will
6563 be permanently REMOVED.
6565 * Gould support removed
6567 Support for the Gould PowerNode and NP1 has been removed.
6569 * New features for SVR4
6571 On SVR4 native platforms (such as Solaris), if you attach to a process
6572 without first loading a symbol file, GDB will now attempt to locate and
6573 load symbols from the running process's executable file.
6575 * Many C++ enhancements
6577 C++ support has been greatly improved. Overload resolution now works properly
6578 in almost all cases. RTTI support is on the way.
6580 * Remote targets can connect to a sub-program
6582 A popen(3) style serial-device has been added. This device starts a
6583 sub-process (such as a stand-alone simulator) and then communicates
6584 with that. The sub-program to run is specified using the syntax
6585 ``|<program> <args>'' vis:
6587 (gdb) set remotedebug 1
6588 (gdb) target extended-remote |mn10300-elf-sim program-args
6590 * MIPS 64 remote protocol
6592 A long standing bug in the mips64 remote protocol where by GDB
6593 expected certain 32 bit registers (ex SR) to be transfered as 32
6594 instead of 64 bits has been fixed.
6596 The command ``set remote-mips64-transfers-32bit-regs on'' has been
6597 added to provide backward compatibility with older versions of GDB.
6599 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
6601 The command ``set remotebinarydownload'' command has been replaced by
6602 ``set remote X-packet''. Other commands in ``set remote'' family
6603 include ``set remote P-packet''.
6605 * Breakpoint commands accept ranges.
6607 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
6608 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
6609 ``tracepoint passcount'' also accepts a range of tracepoints.
6611 * ``apropos'' command added.
6613 The ``apropos'' command searches through command names and
6614 documentation strings, printing out matches, making it much easier to
6615 try to find a command that does what you are looking for.
6619 A new machine oriented interface (MI) has been added to GDB. This
6620 interface is designed for debug environments running GDB as a separate
6621 process. This is part of the long term libGDB project. See the
6622 "GDB/MI" chapter of the GDB manual for further information. It can be
6623 enabled by configuring with:
6625 .../configure --enable-gdbmi
6627 *** Changes in GDB-4.18:
6629 * New native configurations
6631 HP-UX 10.20 hppa*-*-hpux10.20
6632 HP-UX 11.x hppa*-*-hpux11.0*
6633 M68K GNU/Linux m68*-*-linux*
6637 Fujitsu FR30 fr30-*-elf*
6638 Intel StrongARM strongarm-*-*
6639 Mitsubishi D30V d30v-*-*
6641 * OBSOLETE configurations
6643 Gould PowerNode, NP1 np1-*-*, pn-*-*
6645 Configurations that have been declared obsolete will be commented out,
6646 but the code will be left in place. If there is no activity to revive
6647 these configurations before the next release of GDB, the sources will
6648 be permanently REMOVED.
6652 As a compatibility experiment, GDB's source files buildsym.h and
6653 buildsym.c have been converted to pure standard C, no longer
6654 containing any K&R compatibility code. We believe that all systems in
6655 use today either come with a standard C compiler, or have a GCC port
6656 available. If this is not true, please report the affected
6657 configuration to bug-gdb@gnu.org immediately. See the README file for
6658 information about getting a standard C compiler if you don't have one
6663 GDB now uses readline 2.2.
6665 * set extension-language
6667 You can now control the mapping between filename extensions and source
6668 languages by using the `set extension-language' command. For instance,
6669 you can ask GDB to treat .c files as C++ by saying
6670 set extension-language .c c++
6671 The command `info extensions' lists all of the recognized extensions
6672 and their associated languages.
6674 * Setting processor type for PowerPC and RS/6000
6676 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
6677 you can use the `set processor' command to specify what variant of the
6678 PowerPC family you are debugging. The command
6682 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
6683 following PowerPC and RS6000 variants:
6685 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
6686 rs6000 IBM RS6000 ("POWER") architecture, user-level view
6688 403GC IBM PowerPC 403GC
6689 505 Motorola PowerPC 505
6690 860 Motorola PowerPC 860 or 850
6691 601 Motorola PowerPC 601
6692 602 Motorola PowerPC 602
6693 603 Motorola/IBM PowerPC 603 or 603e
6694 604 Motorola PowerPC 604 or 604e
6695 750 Motorola/IBM PowerPC 750 or 750
6697 At the moment, this command just tells GDB what to name the
6698 special-purpose processor registers. Since almost all the affected
6699 registers are inaccessible to user-level programs, this command is
6700 only useful for remote debugging in its present form.
6704 Thanks to a major code donation from Hewlett-Packard, GDB now has much
6705 more extensive support for HP-UX. Added features include shared
6706 library support, kernel threads and hardware watchpoints for 11.00,
6707 support for HP's ANSI C and C++ compilers, and a compatibility mode
6708 for xdb and dbx commands.
6712 HP's donation includes the new concept of catchpoints, which is a
6713 generalization of the old catch command. On HP-UX, it is now possible
6714 to catch exec, fork, and vfork, as well as library loading.
6716 This means that the existing catch command has changed; its first
6717 argument now specifies the type of catch to be set up. See the
6718 output of "help catch" for a list of catchpoint types.
6720 * Debugging across forks
6722 On HP-UX, you can choose which process to debug when a fork() happens
6727 HP has donated a curses-based terminal user interface (TUI). To get
6728 it, build with --enable-tui. Although this can be enabled for any
6729 configuration, at present it only works for native HP debugging.
6731 * GDB remote protocol additions
6733 A new protocol packet 'X' that writes binary data is now available.
6734 Default behavior is to try 'X', then drop back to 'M' if the stub
6735 fails to respond. The settable variable `remotebinarydownload'
6736 allows explicit control over the use of 'X'.
6738 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
6739 full 64-bit address. The command
6741 set remoteaddresssize 32
6743 can be used to revert to the old behaviour. For existing remote stubs
6744 the change should not be noticed, as the additional address information
6747 In order to assist in debugging stubs, you may use the maintenance
6748 command `packet' to send any text string to the stub. For instance,
6750 maint packet heythere
6752 sends the packet "$heythere#<checksum>". Note that it is very easy to
6753 disrupt a debugging session by sending the wrong packet at the wrong
6756 The compare-sections command allows you to compare section data on the
6757 target to what is in the executable file without uploading or
6758 downloading, by comparing CRC checksums.
6760 * Tracing can collect general expressions
6762 You may now collect general expressions at tracepoints. This requires
6763 further additions to the target-side stub; see tracepoint.c and
6764 doc/agentexpr.texi for further details.
6766 * mask-address variable for Mips
6768 For Mips targets, you may control the zeroing of the upper 32 bits of
6769 a 64-bit address by entering `set mask-address on'. This is mainly
6770 of interest to users of embedded R4xxx and R5xxx processors.
6772 * Higher serial baud rates
6774 GDB's serial code now allows you to specify baud rates 57600, 115200,
6775 230400, and 460800 baud. (Note that your host system may not be able
6776 to achieve all of these rates.)
6780 The i960 configuration now includes an initial implementation of a
6781 builtin simulator, contributed by Jim Wilson.
6784 *** Changes in GDB-4.17:
6786 * New native configurations
6788 Alpha GNU/Linux alpha*-*-linux*
6789 Unixware 2.x i[3456]86-unixware2*
6790 Irix 6.x mips*-sgi-irix6*
6791 PowerPC GNU/Linux powerpc-*-linux*
6792 PowerPC Solaris powerpcle-*-solaris*
6793 Sparc GNU/Linux sparc-*-linux*
6794 Motorola sysV68 R3V7.1 m68k-motorola-sysv
6798 Argonaut Risc Chip (ARC) arc-*-*
6799 Hitachi H8/300S h8300*-*-*
6800 Matsushita MN10200 w/simulator mn10200-*-*
6801 Matsushita MN10300 w/simulator mn10300-*-*
6802 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
6803 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
6804 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
6805 Mitsubishi D10V w/simulator d10v-*-*
6806 Mitsubishi M32R/D w/simulator m32r-*-elf*
6807 Tsqware Sparclet sparclet-*-*
6808 NEC V850 w/simulator v850-*-*
6810 * New debugging protocols
6812 ARM with RDI protocol arm*-*-*
6813 M68K with dBUG monitor m68*-*-{aout,coff,elf}
6814 DDB and LSI variants of PMON protocol mips*-*-*
6815 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
6816 PowerPC with SDS protocol powerpc{,le}-*-eabi
6817 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6821 All configurations can now understand and use the DWARF 2 debugging
6822 format. The choice is automatic, if the symbol file contains DWARF 2
6827 GDB now includes basic Java language support. This support is
6828 only useful with Java compilers that produce native machine code.
6830 * solib-absolute-prefix and solib-search-path
6832 For SunOS and SVR4 shared libraries, you may now set the prefix for
6833 loading absolute shared library symbol files, and the search path for
6834 locating non-absolute shared library symbol files.
6836 * Live range splitting
6838 GDB can now effectively debug code for which GCC has performed live
6839 range splitting as part of its optimization. See gdb/doc/LRS for
6840 more details on the expected format of the stabs information.
6844 GDB's support for the GNU Hurd, including thread debugging, has been
6845 updated to work with current versions of the Hurd.
6849 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6850 instruction set. ARM GDB automatically detects when Thumb
6851 instructions are in use, and adjusts disassembly and backtracing
6856 GDB's MIPS target configurations now handle the MIP16 16-bit
6861 GDB now includes support for overlays; if an executable has been
6862 linked such that multiple sections are based at the same address, GDB
6863 will decide which section to use for symbolic info. You can choose to
6864 control the decision manually, using overlay commands, or implement
6865 additional target-side support and use "overlay load-target" to bring
6866 in the overlay mapping. Do "help overlay" for more detail.
6870 The command "info symbol <address>" displays information about
6871 the symbol at the specified address.
6875 The standard remote protocol now includes an extension that allows
6876 asynchronous collection and display of trace data. This requires
6877 extensive support in the target-side debugging stub. Tracing mode
6878 includes a new interaction mode in GDB and new commands: see the
6879 file tracepoint.c for more details.
6883 Configurations for embedded MIPS now include a simulator contributed
6884 by Cygnus Solutions. The simulator supports the instruction sets
6885 of most MIPS variants.
6889 Sparc configurations may now include the ERC32 simulator contributed
6890 by the European Space Agency. The simulator is not built into
6891 Sparc targets by default; configure with --enable-sim to include it.
6895 For target configurations that may include multiple variants of a
6896 basic architecture (such as MIPS and SH), you may now set the
6897 architecture explicitly. "set arch" sets, "info arch" lists
6898 the possible architectures.
6900 *** Changes in GDB-4.16:
6902 * New native configurations
6904 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6905 M68K NetBSD m68k-*-netbsd*
6906 PowerPC AIX 4.x powerpc-*-aix*
6907 PowerPC MacOS powerpc-*-macos*
6908 PowerPC Windows NT powerpcle-*-cygwin32
6909 RS/6000 AIX 4.x rs6000-*-aix4*
6913 ARM with RDP protocol arm-*-*
6914 I960 with MON960 i960-*-coff
6915 MIPS VxWorks mips*-*-vxworks*
6916 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6917 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6919 Matra Sparclet sparclet-*-*
6923 The powerpc-eabi configuration now includes the PSIM simulator,
6924 contributed by Andrew Cagney, with assistance from Mike Meissner.
6925 PSIM is a very elaborate model of the PowerPC, including not only
6926 basic instruction set execution, but also details of execution unit
6927 performance and I/O hardware. See sim/ppc/README for more details.
6931 GDB now works with Solaris 2.5.
6933 * Windows 95/NT native
6935 GDB will now work as a native debugger on Windows 95 and Windows NT.
6936 To build it from source, you must use the "gnu-win32" environment,
6937 which uses a DLL to emulate enough of Unix to run the GNU tools.
6938 Further information, binaries, and sources are available at
6939 ftp.cygnus.com, under pub/gnu-win32.
6941 * dont-repeat command
6943 If a user-defined command includes the command `dont-repeat', then the
6944 command will not be repeated if the user just types return. This is
6945 useful if the command is time-consuming to run, so that accidental
6946 extra keystrokes don't run the same command many times.
6948 * Send break instead of ^C
6950 The standard remote protocol now includes an option to send a break
6951 rather than a ^C to the target in order to interrupt it. By default,
6952 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6954 * Remote protocol timeout
6956 The standard remote protocol includes a new variable `remotetimeout'
6957 that allows you to set the number of seconds before GDB gives up trying
6958 to read from the target. The default value is 2.
6960 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6962 By default GDB will automatically keep track of objects as they are
6963 loaded and unloaded by the dynamic linker. By using the command `set
6964 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6965 when shared library events occur, thus allowing you to set breakpoints
6966 in shared libraries which are explicitly loaded by the inferior.
6968 Note this feature does not work on hpux8. On hpux9 you must link
6969 /usr/lib/end.o into your program. This feature should work
6970 automatically on hpux10.
6972 * Irix 5.x hardware watchpoint support
6974 Irix 5 configurations now support the use of hardware watchpoints.
6976 * Mips protocol "SYN garbage limit"
6978 When debugging a Mips target using the `target mips' protocol, you
6979 may set the number of characters that GDB will ignore by setting
6980 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6981 every character. The default value is 1050.
6983 * Recording and replaying remote debug sessions
6985 If you set `remotelogfile' to the name of a file, gdb will write to it
6986 a recording of a remote debug session. This recording may then be
6987 replayed back to gdb using "gdbreplay". See gdbserver/README for
6988 details. This is useful when you have a problem with GDB while doing
6989 remote debugging; you can make a recording of the session and send it
6990 to someone else, who can then recreate the problem.
6992 * Speedups for remote debugging
6994 GDB includes speedups for downloading and stepping MIPS systems using
6995 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6996 and more efficient S-record downloading.
6998 * Memory use reductions and statistics collection
7000 GDB now uses less memory and reports statistics about memory usage.
7001 Try the `maint print statistics' command, for example.
7003 *** Changes in GDB-4.15:
7005 * Psymtabs for XCOFF
7007 The symbol reader for AIX GDB now uses partial symbol tables. This
7008 can greatly improve startup time, especially for large executables.
7010 * Remote targets use caching
7012 Remote targets now use a data cache to speed up communication with the
7013 remote side. The data cache could lead to incorrect results because
7014 it doesn't know about volatile variables, thus making it impossible to
7015 debug targets which use memory mapped I/O devices. `set remotecache
7016 off' turns the data cache off.
7018 * Remote targets may have threads
7020 The standard remote protocol now includes support for multiple threads
7021 in the target system, using new protocol commands 'H' and 'T'. See
7022 gdb/remote.c for details.
7026 If GDB is configured with `--enable-netrom', then it will include
7027 support for the NetROM ROM emulator from XLNT Designs. The NetROM
7028 acts as though it is a bank of ROM on the target board, but you can
7029 write into it over the network. GDB's support consists only of
7030 support for fast loading into the emulated ROM; to debug, you must use
7031 another protocol, such as standard remote protocol. The usual
7032 sequence is something like
7034 target nrom <netrom-hostname>
7036 target remote <netrom-hostname>:1235
7040 GDB now includes support for the Apple Macintosh, as a host only. It
7041 may be run as either an MPW tool or as a standalone application, and
7042 it can debug through the serial port. All the usual GDB commands are
7043 available, but to the target command, you must supply "serial" as the
7044 device type instead of "/dev/ttyXX". See mpw-README in the main
7045 directory for more information on how to build. The MPW configuration
7046 scripts */mpw-config.in support only a few targets, and only the
7047 mips-idt-ecoff target has been tested.
7051 GDB configuration now uses autoconf. This is not user-visible,
7052 but does simplify configuration and building.
7056 GDB now supports hpux10.
7058 *** Changes in GDB-4.14:
7060 * New native configurations
7062 x86 FreeBSD i[345]86-*-freebsd
7063 x86 NetBSD i[345]86-*-netbsd
7064 NS32k NetBSD ns32k-*-netbsd
7065 Sparc NetBSD sparc-*-netbsd
7069 A29K VxWorks a29k-*-vxworks
7070 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
7071 CPU32 EST-300 emulator m68*-*-est*
7072 PowerPC ELF powerpc-*-elf
7075 * Alpha OSF/1 support for procfs
7077 GDB now supports procfs under OSF/1-2.x and higher, which makes it
7078 possible to attach to running processes. As the mounting of the /proc
7079 filesystem is optional on the Alpha, GDB automatically determines
7080 the availability of /proc during startup. This can lead to problems
7081 if /proc is unmounted after GDB has been started.
7083 * Arguments to user-defined commands
7085 User commands may accept up to 10 arguments separated by whitespace.
7086 Arguments are accessed within the user command via $arg0..$arg9. A
7089 print $arg0 + $arg1 + $arg2
7091 To execute the command use:
7094 Defines the command "adder" which prints the sum of its three arguments.
7095 Note the arguments are text substitutions, so they may reference variables,
7096 use complex expressions, or even perform inferior function calls.
7098 * New `if' and `while' commands
7100 This makes it possible to write more sophisticated user-defined
7101 commands. Both commands take a single argument, which is the
7102 expression to evaluate, and must be followed by the commands to
7103 execute, one per line, if the expression is nonzero, the list being
7104 terminated by the word `end'. The `if' command list may include an
7105 `else' word, which causes the following commands to be executed only
7106 if the expression is zero.
7108 * Fortran source language mode
7110 GDB now includes partial support for Fortran 77. It will recognize
7111 Fortran programs and can evaluate a subset of Fortran expressions, but
7112 variables and functions may not be handled correctly. GDB will work
7113 with G77, but does not yet know much about symbols emitted by other
7116 * Better HPUX support
7118 Most debugging facilities now work on dynamic executables for HPPAs
7119 running hpux9 or later. You can attach to running dynamically linked
7120 processes, but by default the dynamic libraries will be read-only, so
7121 for instance you won't be able to put breakpoints in them. To change
7122 that behavior do the following before running the program:
7128 This will cause the libraries to be mapped private and read-write.
7129 To revert to the normal behavior, do this:
7135 You cannot set breakpoints or examine data in the library until after
7136 the library is loaded if the function/data symbols do not have
7139 GDB can now also read debug symbols produced by the HP C compiler on
7140 HPPAs (sorry, no C++, Fortran or 68k support).
7142 * Target byte order now dynamically selectable
7144 You can choose which byte order to use with a target system, via the
7145 commands "set endian big" and "set endian little", and you can see the
7146 current setting by using "show endian". You can also give the command
7147 "set endian auto", in which case GDB will use the byte order
7148 associated with the executable. Currently, only embedded MIPS
7149 configurations support dynamic selection of target byte order.
7151 * New DOS host serial code
7153 This version uses DPMI interrupts to handle buffered I/O, so you
7154 no longer need to run asynctsr when debugging boards connected to
7157 *** Changes in GDB-4.13:
7159 * New "complete" command
7161 This lists all the possible completions for the rest of the line, if it
7162 were to be given as a command itself. This is intended for use by emacs.
7164 * Trailing space optional in prompt
7166 "set prompt" no longer adds a space for you after the prompt you set. This
7167 allows you to set a prompt which ends in a space or one that does not.
7169 * Breakpoint hit counts
7171 "info break" now displays a count of the number of times the breakpoint
7172 has been hit. This is especially useful in conjunction with "ignore"; you
7173 can ignore a large number of breakpoint hits, look at the breakpoint info
7174 to see how many times the breakpoint was hit, then run again, ignoring one
7175 less than that number, and this will get you quickly to the last hit of
7178 * Ability to stop printing at NULL character
7180 "set print null-stop" will cause GDB to stop printing the characters of
7181 an array when the first NULL is encountered. This is useful when large
7182 arrays actually contain only short strings.
7184 * Shared library breakpoints
7186 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
7187 breakpoints in shared libraries before the executable is run.
7189 * Hardware watchpoints
7191 There is a new hardware breakpoint for the watch command for sparclite
7192 targets. See gdb/sparclite/hw_breakpoint.note.
7194 Hardware watchpoints are also now supported under GNU/Linux.
7198 Annotations have been added. These are for use with graphical interfaces,
7199 and are still experimental. Currently only gdba.el uses these.
7201 * Improved Irix 5 support
7203 GDB now works properly with Irix 5.2.
7205 * Improved HPPA support
7207 GDB now works properly with the latest GCC and GAS.
7209 * New native configurations
7211 Sequent PTX4 i[34]86-sequent-ptx4
7212 HPPA running OSF/1 hppa*-*-osf*
7213 Atari TT running SVR4 m68*-*-sysv4*
7214 RS/6000 LynxOS rs6000-*-lynxos*
7218 OS/9000 i[34]86-*-os9k
7219 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
7222 * Hitachi SH7000 and E7000-PC ICE support
7224 There is now support for communicating with the Hitachi E7000-PC ICE.
7225 This is available automatically when GDB is configured for the SH.
7229 As usual, a variety of small fixes and improvements, both generic
7230 and configuration-specific. See the ChangeLog for more detail.
7232 *** Changes in GDB-4.12:
7234 * Irix 5 is now supported
7238 GDB-4.12 on the HPPA has a number of changes which make it unable
7239 to debug the output from the currently released versions of GCC and
7240 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
7241 of GCC and GAS, versions of these tools designed to work with GDB-4.12
7242 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
7245 *** Changes in GDB-4.11:
7247 * User visible changes:
7251 The "set remotedebug" option is now consistent between the mips remote
7252 target, remote targets using the gdb-specific protocol, UDI (AMD's
7253 debug protocol for the 29k) and the 88k bug monitor. It is now an
7254 integer specifying a debug level (normally 0 or 1, but 2 means more
7255 debugging info for the mips target).
7257 * DEC Alpha native support
7259 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
7260 debug info, but GDB works fairly well with the DEC compiler and should
7261 work with a future GCC release. See the README file for a few
7262 Alpha-specific notes.
7264 * Preliminary thread implementation
7266 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
7268 * LynxOS native and target support for 386
7270 This release has been hosted on LynxOS 2.2, and also can be configured
7271 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
7274 * Improvements in C++ mangling/demangling.
7276 This release has much better g++ debugging, specifically in name
7277 mangling/demangling, virtual function calls, print virtual table,
7278 call methods, ...etc.
7280 *** Changes in GDB-4.10:
7282 * User visible changes:
7284 Remote debugging using the GDB-specific (`target remote') protocol now
7285 supports the `load' command. This is only useful if you have some
7286 other way of getting the stub to the target system, and you can put it
7287 somewhere in memory where it won't get clobbered by the download.
7289 Filename completion now works.
7291 When run under emacs mode, the "info line" command now causes the
7292 arrow to point to the line specified. Also, "info line" prints
7293 addresses in symbolic form (as well as hex).
7295 All vxworks based targets now support a user settable option, called
7296 vxworks-timeout. This option represents the number of seconds gdb
7297 should wait for responses to rpc's. You might want to use this if
7298 your vxworks target is, perhaps, a slow software simulator or happens
7299 to be on the far side of a thin network line.
7303 This release contains support for using a DEC alpha as a GDB host for
7304 cross debugging. Native alpha debugging is not supported yet.
7307 *** Changes in GDB-4.9:
7311 This is the first GDB release which is accompanied by a matching testsuite.
7312 The testsuite requires installation of dejagnu, which should be available
7313 via ftp from most sites that carry GNU software.
7317 'Cfront' style demangling has had its name changed to 'ARM' style, to
7318 emphasize that it was written from the specifications in the C++ Annotated
7319 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
7320 disclaimers, it still generated too much confusion with users attempting to
7321 use gdb with AT&T cfront.
7325 GDB now uses a standard remote interface to a simulator library.
7326 So far, the library contains simulators for the Zilog Z8001/2, the
7327 Hitachi H8/300, H8/500 and Super-H.
7329 * New targets supported
7331 H8/300 simulator h8300-hitachi-hms or h8300hms
7332 H8/500 simulator h8500-hitachi-hms or h8500hms
7333 SH simulator sh-hitachi-hms or sh
7334 Z8000 simulator z8k-zilog-none or z8ksim
7335 IDT MIPS board over serial line mips-idt-ecoff
7337 Cross-debugging to GO32 targets is supported. It requires a custom
7338 version of the i386-stub.c module which is integrated with the
7339 GO32 memory extender.
7341 * New remote protocols
7343 MIPS remote debugging protocol.
7345 * New source languages supported
7347 This version includes preliminary support for Chill, a Pascal like language
7348 used by telecommunications companies. Chill support is also being integrated
7349 into the GNU compiler, but we don't know when it will be publically available.
7352 *** Changes in GDB-4.8:
7354 * HP Precision Architecture supported
7356 GDB now supports HP PA-RISC machines running HPUX. A preliminary
7357 version of this support was available as a set of patches from the
7358 University of Utah. GDB does not support debugging of programs
7359 compiled with the HP compiler, because HP will not document their file
7360 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
7361 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
7363 Many problems in the preliminary version have been fixed.
7365 * Faster and better demangling
7367 We have improved template demangling and fixed numerous bugs in the GNU style
7368 demangler. It can now handle type modifiers such as `static' or `const'. Wide
7369 character types (wchar_t) are now supported. Demangling of each symbol is now
7370 only done once, and is cached when the symbol table for a file is read in.
7371 This results in a small increase in memory usage for C programs, a moderate
7372 increase in memory usage for C++ programs, and a fantastic speedup in
7375 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
7376 from the specifications in the Annotated Reference Manual, which AT&T's
7377 compiler does not actually implement.
7379 * G++ multiple inheritance compiler problem
7381 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
7382 inheritance lattices was reworked to properly discover ambiguities. We
7383 recently found an example which causes this new algorithm to fail in a
7384 very subtle way, producing bad debug information for those classes.
7385 The file 'gcc.patch' (in this directory) can be applied to gcc to
7386 circumvent the problem. A future GCC release will contain a complete
7389 The previous G++ debug info problem (mentioned below for the gdb-4.7
7390 release) is fixed in gcc version 2.3.2.
7392 * Improved configure script
7394 The `configure' script will now attempt to guess your system type if
7395 you don't supply a host system type. The old scheme of supplying a
7396 host system triplet is preferable over using this. All the magic is
7397 done in the new `config.guess' script. Examine it for details.
7399 We have also brought our configure script much more in line with the FSF's
7400 version. It now supports the --with-xxx options. In particular,
7401 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
7402 The resulting GDB will not be able to read arbitrary object file formats --
7403 only the format ``expected'' to be used on the configured target system.
7404 We hope to make this the default in a future release.
7406 * Documentation improvements
7408 There's new internal documentation on how to modify GDB, and how to
7409 produce clean changes to the code. We implore people to read it
7410 before submitting changes.
7412 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
7413 M4 macros. The new texinfo.tex is provided in this release. Pre-built
7414 `info' files are also provided. To build `info' files from scratch,
7415 you will need the latest `makeinfo' release, which will be available in
7416 a future texinfo-X.Y release.
7418 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
7419 We're not sure exactly which versions have this problem, but it has
7420 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
7421 or better. If that isn't possible, there is a patch in
7422 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
7423 around this problem.
7427 GDB now supports array constants that can be used in expressions typed in by
7428 the user. The syntax is `{element, element, ...}'. Ie: you can now type
7429 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
7432 The new directory `gdb/sparclite' contains a program that demonstrates
7433 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
7435 * New native hosts supported
7437 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
7438 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
7440 * New targets supported
7442 AMD 29k family via UDI a29k-amd-udi or udi29k
7444 * New file formats supported
7446 BFD now supports reading HP/PA-RISC executables (SOM file format?),
7447 HPUX core files, and SCO 3.2v2 core files.
7451 Attaching to processes now works again; thanks for the many bug reports.
7453 We have also stomped on a bunch of core dumps caused by
7454 printf_filtered("%s") problems.
7456 We eliminated a copyright problem on the rpc and ptrace header files
7457 for VxWorks, which was discovered at the last minute during the 4.7
7458 release. You should now be able to build a VxWorks GDB.
7460 You can now interrupt gdb while an attached process is running. This
7461 will cause the attached process to stop, and give control back to GDB.
7463 We fixed problems caused by using too many file descriptors
7464 for reading symbols from object files and libraries. This was
7465 especially a problem for programs that used many (~100) shared
7468 The `step' command now only enters a subroutine if there is line number
7469 information for the subroutine. Otherwise it acts like the `next'
7470 command. Previously, `step' would enter subroutines if there was
7471 any debugging information about the routine. This avoids problems
7472 when using `cc -g1' on MIPS machines.
7474 * Internal improvements
7476 GDB's internal interfaces have been improved to make it easier to support
7477 debugging of multiple languages in the future.
7479 GDB now uses a common structure for symbol information internally.
7480 Minimal symbols (derived from linkage symbols in object files), partial
7481 symbols (from a quick scan of debug information), and full symbols
7482 contain a common subset of information, making it easier to write
7483 shared code that handles any of them.
7485 * New command line options
7487 We now accept --silent as an alias for --quiet.
7491 The memory-mapped-malloc library is now licensed under the GNU Library
7492 General Public License.
7494 *** Changes in GDB-4.7:
7496 * Host/native/target split
7498 GDB has had some major internal surgery to untangle the support for
7499 hosts and remote targets. Now, when you configure GDB for a remote
7500 target, it will no longer load in all of the support for debugging
7501 local programs on the host. When fully completed and tested, this will
7502 ensure that arbitrary host/target combinations are possible.
7504 The primary conceptual shift is to separate the non-portable code in
7505 GDB into three categories. Host specific code is required any time GDB
7506 is compiled on that host, regardless of the target. Target specific
7507 code relates to the peculiarities of the target, but can be compiled on
7508 any host. Native specific code is everything else: it can only be
7509 built when the host and target are the same system. Child process
7510 handling and core file support are two common `native' examples.
7512 GDB's use of /proc for controlling Unix child processes is now cleaner.
7513 It has been split out into a single module under the `target_ops' vector,
7514 plus two native-dependent functions for each system that uses /proc.
7516 * New hosts supported
7518 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
7519 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7520 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
7522 * New targets supported
7524 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
7525 68030 and CPU32 m68030-*-*, m68332-*-*
7527 * New native hosts supported
7529 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
7530 (386bsd is not well tested yet)
7531 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
7533 * New file formats supported
7535 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
7536 supports reading of `a.out.adobe' object files, which are an a.out
7537 format extended with minimal information about multiple sections.
7541 `show copying' is the same as the old `info copying'.
7542 `show warranty' is the same as `info warrantee'.
7543 These were renamed for consistency. The old commands continue to work.
7545 `info handle' is a new alias for `info signals'.
7547 You can now define pre-command hooks, which attach arbitrary command
7548 scripts to any command. The commands in the hook will be executed
7549 prior to the user's command. You can also create a hook which will be
7550 executed whenever the program stops. See gdb.texinfo.
7554 We now deal with Cfront style name mangling, and can even extract type
7555 info from mangled symbols. GDB can automatically figure out which
7556 symbol mangling style your C++ compiler uses.
7558 Calling of methods and virtual functions has been improved as well.
7562 The crash that occurred when debugging Sun Ansi-C compiled binaries is
7563 fixed. This was due to mishandling of the extra N_SO stabs output
7566 We also finally got Ultrix 4.2 running in house, and fixed core file
7567 support, with help from a dozen people on the net.
7569 John M. Farrell discovered that the reason that single-stepping was so
7570 slow on all of the Mips based platforms (primarily SGI and DEC) was
7571 that we were trying to demangle and lookup a symbol used for internal
7572 purposes on every instruction that was being stepped through. Changing
7573 the name of that symbol so that it couldn't be mistaken for a C++
7574 mangled symbol sped things up a great deal.
7576 Rich Pixley sped up symbol lookups in general by getting much smarter
7577 about when C++ symbol mangling is necessary. This should make symbol
7578 completion (TAB on the command line) much faster. It's not as fast as
7579 we'd like, but it's significantly faster than gdb-4.6.
7583 A new user controllable variable 'call_scratch_address' can
7584 specify the location of a scratch area to be used when GDB
7585 calls a function in the target. This is necessary because the
7586 usual method of putting the scratch area on the stack does not work
7587 in systems that have separate instruction and data spaces.
7589 We integrated changes to support the 29k UDI (Universal Debugger
7590 Interface), but discovered at the last minute that we didn't have all
7591 of the appropriate copyright paperwork. We are working with AMD to
7592 resolve this, and hope to have it available soon.
7596 We have sped up the remote serial line protocol, especially for targets
7597 with lots of registers. It now supports a new `expedited status' ('T')
7598 message which can be used in place of the existing 'S' status message.
7599 This allows the remote stub to send only the registers that GDB
7600 needs to make a quick decision about single-stepping or conditional
7601 breakpoints, eliminating the need to fetch the entire register set for
7602 each instruction being stepped through.
7604 The GDB remote serial protocol now implements a write-through cache for
7605 registers, only re-reading the registers if the target has run.
7607 There is also a new remote serial stub for SPARC processors. You can
7608 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
7609 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
7610 processor with a serial port.
7614 Configure.in files have become much easier to read and modify. A new
7615 `table driven' format makes it more obvious what configurations are
7616 supported, and what files each one uses.
7620 There is a new opcodes library which will eventually contain all of the
7621 disassembly routines and opcode tables. At present, it only contains
7622 Sparc and Z8000 routines. This will allow the assembler, debugger, and
7623 disassembler (binutils/objdump) to share these routines.
7625 The libiberty library is now copylefted under the GNU Library General
7626 Public License. This allows more liberal use, and was done so libg++
7627 can use it. This makes no difference to GDB, since the Library License
7628 grants all the rights from the General Public License.
7632 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
7633 reference to the stabs symbol info used by the debugger. It is (as far
7634 as we know) the only published document on this fascinating topic. We
7635 encourage you to read it, compare it to the stabs information on your
7636 system, and send improvements on the document in general (to
7637 bug-gdb@prep.ai.mit.edu).
7639 And, of course, many bugs have been fixed.
7642 *** Changes in GDB-4.6:
7644 * Better support for C++ function names
7646 GDB now accepts as input the "demangled form" of C++ overloaded function
7647 names and member function names, and can do command completion on such names
7648 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
7649 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
7650 Make use of command completion, it is your friend.
7652 GDB also now accepts a variety of C++ mangled symbol formats. They are
7653 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
7654 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
7655 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
7656 for the list of formats.
7658 * G++ symbol mangling problem
7660 Recent versions of gcc have a bug in how they emit debugging information for
7661 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
7662 directory) can be applied to gcc to fix the problem. Alternatively, if you
7663 can't fix gcc, you can #define GCC_MANGLE_BUG when compiling gdb/symtab.c. The
7664 usual symptom is difficulty with setting breakpoints on methods. GDB complains
7665 about the method being non-existent. (We believe that version 2.2.2 of GCC has
7668 * New 'maintenance' command
7670 All of the commands related to hacking GDB internals have been moved out of
7671 the main command set, and now live behind the 'maintenance' command. This
7672 can also be abbreviated as 'mt'. The following changes were made:
7674 dump-me -> maintenance dump-me
7675 info all-breakpoints -> maintenance info breakpoints
7676 printmsyms -> maintenance print msyms
7677 printobjfiles -> maintenance print objfiles
7678 printpsyms -> maintenance print psymbols
7679 printsyms -> maintenance print symbols
7681 The following commands are new:
7683 maintenance demangle Call internal GDB demangler routine to
7684 demangle a C++ link name and prints the result.
7685 maintenance print type Print a type chain for a given symbol
7687 * Change to .gdbinit file processing
7689 We now read the $HOME/.gdbinit file before processing the argv arguments
7690 (e.g. reading symbol files or core files). This allows global parameters to
7691 be set, which will apply during the symbol reading. The ./.gdbinit is still
7692 read after argv processing.
7694 * New hosts supported
7696 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
7698 GNU/Linux support i386-unknown-linux or linux
7700 We are also including code to support the HP/PA running BSD and HPUX. This
7701 is almost guaranteed not to work, as we didn't have time to test or build it
7702 for this release. We are including it so that the more adventurous (or
7703 masochistic) of you can play with it. We also had major problems with the
7704 fact that the compiler that we got from HP doesn't support the -g option.
7707 * New targets supported
7709 Hitachi H8/300 h8300-hitachi-hms or h8300hms
7711 * More smarts about finding #include files
7713 GDB now remembers the compilation directory for all include files, and for
7714 all files from which C is generated (like yacc and lex sources). This
7715 greatly improves GDB's ability to find yacc/lex sources, and include files,
7716 especially if you are debugging your program from a directory different from
7717 the one that contains your sources.
7719 We also fixed a bug which caused difficulty with listing and setting
7720 breakpoints in include files which contain C code. (In the past, you had to
7721 try twice in order to list an include file that you hadn't looked at before.)
7723 * Interesting infernals change
7725 GDB now deals with arbitrary numbers of sections, where the symbols for each
7726 section must be relocated relative to that section's landing place in the
7727 target's address space. This work was needed to support ELF with embedded
7728 stabs used by Solaris-2.0.
7730 * Bug fixes (of course!)
7732 There have been loads of fixes for the following things:
7733 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
7734 i960, stabs, DOS(GO32), procfs, etc...
7736 See the ChangeLog for details.
7738 *** Changes in GDB-4.5:
7740 * New machines supported (host and target)
7742 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
7744 SGI Irix-4.x mips-sgi-irix4 or iris4
7746 * New malloc package
7748 GDB now uses a new memory manager called mmalloc, based on gmalloc.
7749 Mmalloc is capable of handling multiple heaps of memory. It is also
7750 capable of saving a heap to a file, and then mapping it back in later.
7751 This can be used to greatly speedup the startup of GDB by using a
7752 pre-parsed symbol table which lives in a mmalloc managed heap. For
7753 more details, please read mmalloc/mmalloc.texi.
7757 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
7758 'help info proc' for details.
7760 * MIPS ecoff symbol table format
7762 The code that reads MIPS symbol table format is now supported on all hosts.
7763 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
7766 * File name changes for MS-DOS
7768 Many files in the config directories have been renamed to make it easier to
7769 support GDB on MS-DOSe systems (which have very restrictive file name
7770 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
7771 environment) is close to working but has some remaining problems. Note
7772 that debugging of DOS programs is not supported, due to limitations
7773 in the ``operating system'', but it can be used to host cross-debugging.
7775 * Cross byte order fixes
7777 Many fixes have been made to support cross debugging of Sparc and MIPS
7778 targets from hosts whose byte order differs.
7780 * New -mapped and -readnow options
7782 If memory-mapped files are available on your system through the 'mmap'
7783 system call, you can use the -mapped option on the `file' or
7784 `symbol-file' commands to cause GDB to write the symbols from your
7785 program into a reusable file. If the program you are debugging is
7786 called `/path/fred', the mapped symbol file will be `./fred.syms'.
7787 Future GDB debugging sessions will notice the presence of this file,
7788 and will quickly map in symbol information from it, rather than reading
7789 the symbol table from the executable program. Using the '-mapped'
7790 option in a GDB `file' or `symbol-file' command has the same effect as
7791 starting GDB with the '-mapped' command-line option.
7793 You can cause GDB to read the entire symbol table immediately by using
7794 the '-readnow' option with any of the commands that load symbol table
7795 information (or on the GDB command line). This makes the command
7796 slower, but makes future operations faster.
7798 The -mapped and -readnow options are typically combined in order to
7799 build a `fred.syms' file that contains complete symbol information.
7800 A simple GDB invocation to do nothing but build a `.syms' file for future
7803 gdb -batch -nx -mapped -readnow programname
7805 The `.syms' file is specific to the host machine on which GDB is run.
7806 It holds an exact image of GDB's internal symbol table. It cannot be
7807 shared across multiple host platforms.
7809 * longjmp() handling
7811 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
7812 siglongjmp() without losing control. This feature has not yet been ported to
7813 all systems. It currently works on many 386 platforms, all MIPS-based
7814 platforms (SGI, DECstation, etc), and Sun3/4.
7818 Preliminary work has been put in to support the new Solaris OS from Sun. At
7819 this time, it can control and debug processes, but it is not capable of
7824 As always, many many bug fixes. The major areas were with g++, and mipsread.
7825 People using the MIPS-based platforms should experience fewer mysterious
7826 crashes and trashed symbol tables.
7828 *** Changes in GDB-4.4:
7830 * New machines supported (host and target)
7832 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7834 BSD Reno on Vax vax-dec-bsd
7835 Ultrix on Vax vax-dec-ultrix
7837 * New machines supported (target)
7839 AMD 29000 embedded, using EBMON a29k-none-none
7843 GDB continues to improve its handling of C++. `References' work better.
7844 The demangler has also been improved, and now deals with symbols mangled as
7845 per the Annotated C++ Reference Guide.
7847 GDB also now handles `stabs' symbol information embedded in MIPS
7848 `ecoff' symbol tables. Since the ecoff format was not easily
7849 extensible to handle new languages such as C++, this appeared to be a
7850 good way to put C++ debugging info into MIPS binaries. This option
7851 will be supported in the GNU C compiler, version 2, when it is
7854 * New features for SVR4
7856 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7857 shared libraries. Debugging dynamically linked programs should present
7858 only minor differences from debugging statically linked programs.
7860 The `info proc' command will print out information about any process
7861 on an SVR4 system (including the one you are debugging). At the moment,
7862 it prints the address mappings of the process.
7864 If you bring up GDB on another SVR4 system, please send mail to
7865 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7867 * Better dynamic linking support in SunOS
7869 Reading symbols from shared libraries which contain debugging symbols
7870 now works properly. However, there remain issues such as automatic
7871 skipping of `transfer vector' code during function calls, which
7872 make it harder to debug code in a shared library, than to debug the
7873 same code linked statically.
7877 GDB is now using the latest `getopt' routines from the FSF. This
7878 version accepts the -- prefix for options with long names. GDB will
7879 continue to accept the old forms (-option and +option) as well.
7880 Various single letter abbreviations for options have been explicity
7881 added to the option table so that they won't get overshadowed in the
7882 future by other options that begin with the same letter.
7886 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7887 Many assorted bugs have been handled. Many more remain to be handled.
7888 See the various ChangeLog files (primarily in gdb and bfd) for details.
7891 *** Changes in GDB-4.3:
7893 * New machines supported (host and target)
7895 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7896 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7897 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7899 * Almost SCO Unix support
7901 We had hoped to support:
7902 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7903 (except for core file support), but we discovered very late in the release
7904 that it has problems with process groups that render gdb unusable. Sorry
7905 about that. I encourage people to fix it and post the fixes.
7907 * Preliminary ELF and DWARF support
7909 GDB can read ELF object files on System V Release 4, and can handle
7910 debugging records for C, in DWARF format, in ELF files. This support
7911 is preliminary. If you bring up GDB on another SVR4 system, please
7912 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7917 GDB now uses the latest `readline' library. One user-visible change
7918 is that two tabs will list possible command completions, which previously
7919 required typing M-? (meta-question mark, or ESC ?).
7923 The `stepi' bug that many of you noticed has been squashed.
7924 Many bugs in C++ have been handled. Many more remain to be handled.
7925 See the various ChangeLog files (primarily in gdb and bfd) for details.
7927 * State of the MIPS world (in case you wondered):
7929 GDB can understand the symbol tables emitted by the compilers
7930 supplied by most vendors of MIPS-based machines, including DEC. These
7931 symbol tables are in a format that essentially nobody else uses.
7933 Some versions of gcc come with an assembler post-processor called
7934 mips-tfile. This program is required if you want to do source-level
7935 debugging of gcc-compiled programs. I believe FSF does not ship
7936 mips-tfile with gcc version 1, but it will eventually come with gcc
7939 Debugging of g++ output remains a problem. g++ version 1.xx does not
7940 really support it at all. (If you're lucky, you should be able to get
7941 line numbers and stack traces to work, but no parameters or local
7942 variables.) With some work it should be possible to improve the
7945 When gcc version 2 is released, you will have somewhat better luck.
7946 However, even then you will get confusing results for inheritance and
7949 We will eventually provide full debugging of g++ output on
7950 DECstations. This will probably involve some kind of stabs-in-ecoff
7951 encapulation, but the details have not been worked out yet.
7954 *** Changes in GDB-4.2:
7956 * Improved configuration
7958 Only one copy of `configure' exists now, and it is not self-modifying.
7959 Porting BFD is simpler.
7963 The `step' and `next' commands now only stop at the first instruction
7964 of a source line. This prevents the multiple stops that used to occur
7965 in switch statements, for-loops, etc. `Step' continues to stop if a
7966 function that has debugging information is called within the line.
7970 Lots of small bugs fixed. More remain.
7972 * New host supported (not target)
7974 Intel 386 PC clone running Mach i386-none-mach
7977 *** Changes in GDB-4.1:
7979 * Multiple source language support
7981 GDB now has internal scaffolding to handle several source languages.
7982 It determines the type of each source file from its filename extension,
7983 and will switch expression parsing and number formatting to match the
7984 language of the function in the currently selected stack frame.
7985 You can also specifically set the language to be used, with
7986 `set language c' or `set language modula-2'.
7990 GDB now has preliminary support for the GNU Modula-2 compiler,
7991 currently under development at the State University of New York at
7992 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7993 continue through the fall of 1991 and into 1992.
7995 Other Modula-2 compilers are currently not supported, and attempting to
7996 debug programs compiled with them will likely result in an error as the
7997 symbol table is read. Feel free to work on it, though!
7999 There are hooks in GDB for strict type checking and range checking,
8000 in the `Modula-2 philosophy', but they do not currently work.
8004 GDB can now write to executable and core files (e.g. patch
8005 a variable's value). You must turn this switch on, specify
8006 the file ("exec foo" or "core foo"), *then* modify it, e.g.
8007 by assigning a new value to a variable. Modifications take
8010 * Automatic SunOS shared library reading
8012 When you run your program, GDB automatically determines where its
8013 shared libraries (if any) have been loaded, and reads their symbols.
8014 The `share' command is no longer needed. This also works when
8015 examining core files.
8019 You can specify the number of lines that the `list' command shows.
8022 * New machines supported (host and target)
8024 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
8025 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
8026 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
8028 * New hosts supported (not targets)
8030 IBM RT/PC: romp-ibm-aix or rtpc
8032 * New targets supported (not hosts)
8034 AMD 29000 embedded with COFF a29k-none-coff
8035 AMD 29000 embedded with a.out a29k-none-aout
8036 Ultracomputer remote kernel debug a29k-nyu-kern
8038 * New remote interfaces
8044 *** Changes in GDB-4.0:
8048 Wide output is wrapped at good places to make the output more readable.
8050 Gdb now supports cross-debugging from a host machine of one type to a
8051 target machine of another type. Communication with the target system
8052 is over serial lines. The ``target'' command handles connecting to the
8053 remote system; the ``load'' command will download a program into the
8054 remote system. Serial stubs for the m68k and i386 are provided. Gdb
8055 also supports debugging of realtime processes running under VxWorks,
8056 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
8057 stub on the target system.
8059 New CPUs supported include the AMD 29000 and Intel 960.
8061 GDB now reads object files and symbol tables via a ``binary file''
8062 library, which allows a single copy of GDB to debug programs of multiple
8063 object file types such as a.out and coff.
8065 There is now a GDB reference card in "doc/refcard.tex". (Make targets
8066 refcard.dvi and refcard.ps are available to format it).
8069 * Control-Variable user interface simplified
8071 All variables that control the operation of the debugger can be set
8072 by the ``set'' command, and displayed by the ``show'' command.
8074 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
8075 ``Show prompt'' produces the response:
8076 Gdb's prompt is new-gdb=>.
8078 What follows are the NEW set commands. The command ``help set'' will
8079 print a complete list of old and new set commands. ``help set FOO''
8080 will give a longer description of the variable FOO. ``show'' will show
8081 all of the variable descriptions and their current settings.
8083 confirm on/off: Enables warning questions for operations that are
8084 hard to recover from, e.g. rerunning the program while
8085 it is already running. Default is ON.
8087 editing on/off: Enables EMACS style command line editing
8088 of input. Previous lines can be recalled with
8089 control-P, the current line can be edited with control-B,
8090 you can search for commands with control-R, etc.
8093 history filename NAME: NAME is where the gdb command history
8094 will be stored. The default is .gdb_history,
8095 or the value of the environment variable
8098 history size N: The size, in commands, of the command history. The
8099 default is 256, or the value of the environment variable
8102 history save on/off: If this value is set to ON, the history file will
8103 be saved after exiting gdb. If set to OFF, the
8104 file will not be saved. The default is OFF.
8106 history expansion on/off: If this value is set to ON, then csh-like
8107 history expansion will be performed on
8108 command line input. The default is OFF.
8110 radix N: Sets the default radix for input and output. It can be set
8111 to 8, 10, or 16. Note that the argument to "radix" is interpreted
8112 in the current radix, so "set radix 10" is always a no-op.
8114 height N: This integer value is the number of lines on a page. Default
8115 is 24, the current `stty rows'' setting, or the ``li#''
8116 setting from the termcap entry matching the environment
8119 width N: This integer value is the number of characters on a line.
8120 Default is 80, the current `stty cols'' setting, or the ``co#''
8121 setting from the termcap entry matching the environment
8124 Note: ``set screensize'' is obsolete. Use ``set height'' and
8125 ``set width'' instead.
8127 print address on/off: Print memory addresses in various command displays,
8128 such as stack traces and structure values. Gdb looks
8129 more ``symbolic'' if you turn this off; it looks more
8130 ``machine level'' with it on. Default is ON.
8132 print array on/off: Prettyprint arrays. New convenient format! Default
8135 print demangle on/off: Print C++ symbols in "source" form if on,
8138 print asm-demangle on/off: Same, for assembler level printouts
8141 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
8144 * Support for Epoch Environment.
8146 The epoch environment is a version of Emacs v18 with windowing. One
8147 new command, ``inspect'', is identical to ``print'', except that if you
8148 are running in the epoch environment, the value is printed in its own
8152 * Support for Shared Libraries
8154 GDB can now debug programs and core files that use SunOS shared libraries.
8155 Symbols from a shared library cannot be referenced
8156 before the shared library has been linked with the program (this
8157 happens after you type ``run'' and before the function main() is entered).
8158 At any time after this linking (including when examining core files
8159 from dynamically linked programs), gdb reads the symbols from each
8160 shared library when you type the ``sharedlibrary'' command.
8161 It can be abbreviated ``share''.
8163 sharedlibrary REGEXP: Load shared object library symbols for files
8164 matching a unix regular expression. No argument
8165 indicates to load symbols for all shared libraries.
8167 info sharedlibrary: Status of loaded shared libraries.
8172 A watchpoint stops execution of a program whenever the value of an
8173 expression changes. Checking for this slows down execution
8174 tremendously whenever you are in the scope of the expression, but is
8175 quite useful for catching tough ``bit-spreader'' or pointer misuse
8176 problems. Some machines such as the 386 have hardware for doing this
8177 more quickly, and future versions of gdb will use this hardware.
8179 watch EXP: Set a watchpoint (breakpoint) for an expression.
8181 info watchpoints: Information about your watchpoints.
8183 delete N: Deletes watchpoint number N (same as breakpoints).
8184 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
8185 enable N: Re-enables watchpoint number N (same as breakpoints).
8188 * C++ multiple inheritance
8190 When used with a GCC version 2 compiler, GDB supports multiple inheritance
8193 * C++ exception handling
8195 Gdb now supports limited C++ exception handling. Besides the existing
8196 ability to breakpoint on an exception handler, gdb can breakpoint on
8197 the raising of an exception (before the stack is peeled back to the
8200 catch FOO: If there is a FOO exception handler in the dynamic scope,
8201 set a breakpoint to catch exceptions which may be raised there.
8202 Multiple exceptions (``catch foo bar baz'') may be caught.
8204 info catch: Lists all exceptions which may be caught in the
8205 current stack frame.
8208 * Minor command changes
8210 The command ``call func (arg, arg, ...)'' now acts like the print
8211 command, except it does not print or save a value if the function's result
8212 is void. This is similar to dbx usage.
8214 The ``up'' and ``down'' commands now always print the frame they end up
8215 at; ``up-silently'' and `down-silently'' can be used in scripts to change
8216 frames without printing.
8218 * New directory command
8220 'dir' now adds directories to the FRONT of the source search path.
8221 The path starts off empty. Source files that contain debug information
8222 about the directory in which they were compiled can be found even
8223 with an empty path; Sun CC and GCC include this information. If GDB can't
8224 find your source file in the current directory, type "dir .".
8226 * Configuring GDB for compilation
8228 For normal use, type ``./configure host''. See README or gdb.texinfo
8231 GDB now handles cross debugging. If you are remotely debugging between
8232 two different machines, type ``./configure host -target=targ''.
8233 Host is the machine where GDB will run; targ is the machine
8234 where the program that you are debugging will run.