1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
6 * The "info source" command now displays the producer string if it was
7 present in the debug info. This typically includes the compiler version
8 and may include things like its command line arguments.
12 ** gdb.Objfile objects have a new attribute "username",
13 which is the name of the objfile as specified by the user,
14 without, for example, resolving symlinks.
18 * The command 'thread apply all' can now support new option '-ascending'
19 to call its specified command for all threads in ascending order.
21 * Python/Guile scripting
23 ** GDB now supports auto-loading of Python/Guile scripts contained in the
24 special section named `.debug_gdb_scripts'.
26 *** Changes in GDB 7.9
28 * GDB now supports hardware watchpoints on x86 GNU Hurd.
32 ** You can now access frame registers from Python scripts.
33 ** New attribute 'producer' for gdb.Symtab objects.
34 ** gdb.Objfile objects have a new attribute "progspace",
35 which is the gdb.Progspace object of the containing program space.
36 ** gdb.Objfile objects have a new attribute "owner".
37 ** gdb.Objfile objects have a new attribute "build_id",
38 which is the build ID generated when the file was built.
39 ** gdb.Objfile objects have a new method "add_separate_debug_file".
40 ** A new event "gdb.clear_objfiles" has been added, triggered when
41 selecting a new file to debug.
42 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
43 ** New function gdb.lookup_objfile.
45 New events which are triggered when GDB modifies the state of the
48 ** gdb.events.inferior_call_pre: Function call is about to be made.
49 ** gdb.events.inferior_call_post: Function call has just been made.
50 ** gdb.events.memory_changed: A memory location has been altered.
51 ** gdb.events.register_changed: A register has been altered.
53 * New Python-based convenience functions:
55 ** $_caller_is(name [, number_of_frames])
56 ** $_caller_matches(regexp [, number_of_frames])
57 ** $_any_caller_is(name [, number_of_frames])
58 ** $_any_caller_matches(regexp [, number_of_frames])
60 * GDB now supports the compilation and injection of source code into
61 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
62 to compile the source code to object code, and if successful, inject
63 and execute that code within the current context of the inferior.
64 Currently the C language is supported. The commands used to
65 interface with this new feature are:
67 compile code [-raw|-r] [--] [source code]
68 compile file [-raw|-r] filename
72 demangle [-l language] [--] name
73 Demangle "name" in the specified language, or the current language
74 if elided. This command is renamed from the "maint demangle" command.
75 The latter is kept as a no-op to avoid "maint demangle" being interpreted
76 as "maint demangler-warning".
78 queue-signal signal-name-or-number
79 Queue a signal to be delivered to the thread when it is resumed.
81 add-auto-load-scripts-directory directory
82 Add entries to the list of directories from which to load auto-loaded
85 maint print user-registers
86 List all currently available "user" registers.
88 compile code [-r|-raw] [--] [source code]
89 Compile, inject, and execute in the inferior the executable object
90 code produced by compiling the provided source code.
92 compile file [-r|-raw] filename
93 Compile and inject into the inferior the executable object code
94 produced by compiling the source code stored in the filename
97 * On resume, GDB now always passes the signal the program had stopped
98 for to the thread the signal was sent to, even if the user changed
99 threads before resuming. Previously GDB would often (but not
100 always) deliver the signal to the thread that happens to be current
103 * Conversely, the "signal" command now consistently delivers the
104 requested signal to the current thread. GDB now asks for
105 confirmation if the program had stopped for a signal and the user
106 switched threads meanwhile.
108 * "breakpoint always-inserted" modes "off" and "auto" merged.
110 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
111 won't remove breakpoints from the target until all threads stop,
112 even in non-stop mode. The "auto" mode has been removed, and "off"
113 is now the default mode.
117 set debug symbol-lookup
118 show debug symbol-lookup
119 Control display of debugging info regarding symbol lookup.
123 ** The -list-thread-groups command outputs an exit-code field for
124 inferiors that have exited.
128 MIPS SDE mips*-sde*-elf*
132 Support for these obsolete configurations has been removed.
134 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
135 SGI Irix-5.x mips-*-irix5*
136 SGI Irix-6.x mips-*-irix6*
137 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
138 VAX running Ultrix vax-*-ultrix*
140 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
141 and "assf"), have been removed. Use the "sharedlibrary" command, or
142 its alias "share", instead.
144 *** Changes in GDB 7.8
146 * New command line options
149 This is an alias for the --data-directory option.
151 * GDB supports printing and modifying of variable length automatic arrays
152 as specified in ISO C99.
154 * The ARM simulator now supports instruction level tracing
155 with or without disassembly.
159 GDB now has support for scripting using Guile. Whether this is
160 available is determined at configure time.
161 Guile version 2.0 or greater is required.
162 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
164 * New commands (for set/show, see "New options" below)
168 Invoke CODE by passing it to the Guile interpreter.
172 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
174 info auto-load guile-scripts [regexp]
175 Print the list of automatically loaded Guile scripts.
177 * The source command is now capable of sourcing Guile scripts.
178 This feature is dependent on the debugger being built with Guile support.
182 set print symbol-loading (off|brief|full)
183 show print symbol-loading
184 Control whether to print informational messages when loading symbol
185 information for a file. The default is "full", but when debugging
186 programs with large numbers of shared libraries the amount of output
189 set guile print-stack (none|message|full)
190 show guile print-stack
191 Show a stack trace when an error is encountered in a Guile script.
193 set auto-load guile-scripts (on|off)
194 show auto-load guile-scripts
195 Control auto-loading of Guile script files.
197 maint ada set ignore-descriptive-types (on|off)
198 maint ada show ignore-descriptive-types
199 Control whether the debugger should ignore descriptive types in Ada
200 programs. The default is not to ignore the descriptive types. See
201 the user manual for more details on descriptive types and the intended
202 usage of this option.
204 set auto-connect-native-target
206 Control whether GDB is allowed to automatically connect to the
207 native target for the run, attach, etc. commands when not connected
208 to any target yet. See also "target native" below.
210 set record btrace replay-memory-access (read-only|read-write)
211 show record btrace replay-memory-access
212 Control what memory accesses are allowed during replay.
214 maint set target-async (on|off)
215 maint show target-async
216 This controls whether GDB targets operate in synchronous or
217 asynchronous mode. Normally the default is asynchronous, if it is
218 available; but this can be changed to more easily debug problems
219 occurring only in synchronous mode.
221 set mi-async (on|off)
223 Control whether MI asynchronous mode is preferred. This supersedes
224 "set target-async" of previous GDB versions.
226 * "set target-async" is deprecated as a CLI option and is now an alias
227 for "set mi-async" (only puts MI into async mode).
229 * Background execution commands (e.g., "c&", "s&", etc.) are now
230 possible ``out of the box'' if the target supports them. Previously
231 the user would need to explicitly enable the possibility with the
232 "set target-async on" command.
234 * New features in the GDB remote stub, GDBserver
236 ** New option --debug-format=option1[,option2,...] allows one to add
237 additional text to each output. At present only timestamps
238 are supported: --debug-format=timestamps.
239 Timestamps can also be turned on with the
240 "monitor set debug-format timestamps" command from GDB.
242 * The 'record instruction-history' command now starts counting instructions
243 at one. This also affects the instruction ranges reported by the
244 'record function-call-history' command when given the /i modifier.
246 * The command 'record function-call-history' supports a new modifier '/c' to
247 indent the function names based on their call stack depth.
248 The fields for the '/i' and '/l' modifier have been reordered.
249 The source line range is now prefixed with 'at'.
250 The instruction range is now prefixed with 'inst'.
251 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
252 "record instruction-history" and "list" commands.
254 * The ranges given as arguments to the 'record function-call-history' and
255 'record instruction-history' commands are now inclusive.
257 * The btrace record target now supports the 'record goto' command.
258 For locations inside the execution trace, the back trace is computed
259 based on the information stored in the execution trace.
261 * The btrace record target supports limited reverse execution and replay.
262 The target does not record data and therefore does not allow reading
265 * The "catch syscall" command now works on s390*-linux* targets.
267 * The "compare-sections" command is no longer specific to target
268 remote. It now works with all targets.
270 * All native targets are now consistently called "native".
271 Consequently, the "target child", "target GNU", "target djgpp",
272 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
273 commands have been replaced with "target native". The QNX/NTO port
274 leaves the "procfs" target in place and adds a "native" target for
275 consistency with other ports. The impact on users should be minimal
276 as these commands previously either throwed an error, or were
277 no-ops. The target's name is visible in the output of the following
278 commands: "help target", "info target", "info files", "maint print
281 * The "target native" command now connects to the native target. This
282 can be used to launch native programs even when "set
283 auto-connect-native-target" is set to off.
285 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
287 * Support for Intel(R) AVX-512 registers on GNU/Linux.
288 Support displaying and modifying Intel(R) AVX-512 registers
289 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
293 qXfer:btrace:read's annex
294 The qXfer:btrace:read packet supports a new annex 'delta' to read
295 branch trace incrementally.
299 ** Valid Python operations on gdb.Value objects representing
300 structs/classes invoke the corresponding overloaded operators if
302 ** New `Xmethods' feature in the Python API. Xmethods are
303 additional methods or replacements for existing methods of a C++
304 class. This feature is useful for those cases where a method
305 defined in C++ source code could be inlined or optimized out by
306 the compiler, making it unavailable to GDB.
309 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
311 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
312 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
313 its alias "share", instead.
315 * The commands "set remotebaud" and "show remotebaud" are no longer
316 supported. Use "set serial baud" and "show serial baud" (respectively)
321 ** A new option "-gdb-set mi-async" replaces "-gdb-set
322 target-async". The latter is left as a deprecated alias of the
323 former for backward compatibility. If the target supports it,
324 CLI background execution commands are now always possible by
325 default, independently of whether the frontend stated a
326 preference for asynchronous execution with "-gdb-set mi-async".
327 Previously "-gdb-set target-async off" affected both MI execution
328 commands and CLI execution commands.
330 *** Changes in GDB 7.7
332 * Improved support for process record-replay and reverse debugging on
333 arm*-linux* targets. Support for thumb32 and syscall instruction
334 recording has been added.
336 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
338 * GDB now supports Fission DWP file format version 2.
339 http://gcc.gnu.org/wiki/DebugFission
341 * New convenience function "$_isvoid", to check whether an expression
342 is void. A void expression is an expression where the type of the
343 result is "void". For example, some convenience variables may be
344 "void" when evaluated (e.g., "$_exitcode" before the execution of
345 the program being debugged; or an undefined convenience variable).
346 Another example, when calling a function whose return type is
349 * The "maintenance print objfiles" command now takes an optional regexp.
351 * The "catch syscall" command now works on arm*-linux* targets.
353 * GDB now consistently shows "<not saved>" when printing values of
354 registers the debug info indicates have not been saved in the frame
355 and there's nowhere to retrieve them from
356 (callee-saved/call-clobbered registers):
361 (gdb) info registers rax
364 Before, the former would print "<optimized out>", and the latter
365 "*value not available*".
367 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
372 ** Frame filters and frame decorators have been added.
373 ** Temporary breakpoints are now supported.
374 ** Line tables representation has been added.
375 ** New attribute 'parent_type' for gdb.Field objects.
376 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
377 ** New attribute 'name' for gdb.Type objects.
381 Nios II ELF nios2*-*-elf
382 Nios II GNU/Linux nios2*-*-linux
383 Texas Instruments MSP430 msp430*-*-elf
385 * Removed native configurations
387 Support for these a.out NetBSD and OpenBSD obsolete configurations has
388 been removed. ELF variants of these configurations are kept supported.
390 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
391 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
392 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
393 i[34567]86-*-openbsd3.[0-3]
394 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
395 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
396 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
400 Like "catch throw", but catches a re-thrown exception.
402 Renamed from old "maint check-symtabs".
404 Perform consistency checks on symtabs.
406 Expand symtabs matching an optional regexp.
409 Display the details of GDB configure-time options.
411 maint set|show per-command
412 maint set|show per-command space
413 maint set|show per-command time
414 maint set|show per-command symtab
415 Enable display of per-command gdb resource usage.
417 remove-symbol-file FILENAME
418 remove-symbol-file -a ADDRESS
419 Remove a symbol file added via add-symbol-file. The file to remove
420 can be identified by its filename or by an address that lies within
421 the boundaries of this symbol file in memory.
424 info exceptions REGEXP
425 Display the list of Ada exceptions defined in the program being
426 debugged. If provided, only the exceptions whose names match REGEXP
431 set debug symfile off|on
433 Control display of debugging info regarding reading symbol files and
434 symbol tables within those files
436 set print raw frame-arguments
437 show print raw frame-arguments
438 Set/show whether to print frame arguments in raw mode,
439 disregarding any defined pretty-printers.
441 set remote trace-status-packet
442 show remote trace-status-packet
443 Set/show the use of remote protocol qTStatus packet.
447 Control display of debugging messages related to Nios II targets.
451 Control whether target-assisted range stepping is enabled.
453 set startup-with-shell
454 show startup-with-shell
455 Specifies whether Unix child processes are started via a shell or
460 Use the target memory cache for accesses to the code segment. This
461 improves performance of remote debugging (particularly disassembly).
463 * You can now use a literal value 'unlimited' for options that
464 interpret 0 or -1 as meaning "unlimited". E.g., "set
465 trace-buffer-size unlimited" is now an alias for "set
466 trace-buffer-size -1" and "set height unlimited" is now an alias for
469 * The "set debug symtab-create" debugging option of GDB has been changed to
470 accept a verbosity level. 0 means "off", 1 provides basic debugging
471 output, and values of 2 or greater provides more verbose output.
473 * New command-line options
475 Display the details of GDB configure-time options.
477 * The command 'tsave' can now support new option '-ctf' to save trace
478 buffer in Common Trace Format.
480 * Newly installed $prefix/bin/gcore acts as a shell interface for the
483 * GDB now implements the the C++ 'typeid' operator.
485 * The new convenience variable $_exception holds the exception being
486 thrown or caught at an exception-related catchpoint.
488 * The exception-related catchpoints, like "catch throw", now accept a
489 regular expression which can be used to filter exceptions by type.
491 * The new convenience variable $_exitsignal is automatically set to
492 the terminating signal number when the program being debugged dies
493 due to an uncaught signal.
497 ** All MI commands now accept an optional "--language" option.
498 Support for this feature can be verified by using the "-list-features"
499 command, which should contain "language-option".
501 ** The new command -info-gdb-mi-command allows the user to determine
502 whether a GDB/MI command is supported or not.
504 ** The "^error" result record returned when trying to execute an undefined
505 GDB/MI command now provides a variable named "code" whose content is the
506 "undefined-command" error code. Support for this feature can be verified
507 by using the "-list-features" command, which should contain
508 "undefined-command-error-code".
510 ** The -trace-save MI command can optionally save trace buffer in Common
513 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
515 ** The command -data-list-register-values now accepts an optional
516 "--skip-unavailable" option. When used, only the available registers
519 ** The new command -trace-frame-collected dumps collected variables,
520 computed expressions, tvars, memory and registers in a traceframe.
522 ** The commands -stack-list-locals, -stack-list-arguments and
523 -stack-list-variables now accept an option "--skip-unavailable".
524 When used, only the available locals or arguments are displayed.
526 ** The -exec-run command now accepts an optional "--start" option.
527 When used, the command follows the same semantics as the "start"
528 command, stopping the program's execution at the start of its
529 main subprogram. Support for this feature can be verified using
530 the "-list-features" command, which should contain
531 "exec-run-start-option".
533 ** The new commands -catch-assert and -catch-exceptions insert
534 catchpoints stopping the program when Ada exceptions are raised.
536 ** The new command -info-ada-exceptions provides the equivalent of
537 the new "info exceptions" command.
539 * New system-wide configuration scripts
540 A GDB installation now provides scripts suitable for use as system-wide
541 configuration scripts for the following systems:
545 * GDB now supports target-assigned range stepping with remote targets.
546 This improves the performance of stepping source lines by reducing
547 the number of control packets from/to GDB. See "New remote packets"
550 * GDB now understands the element 'tvar' in the XML traceframe info.
551 It has the id of the collected trace state variables.
553 * On S/390 targets that provide the transactional-execution feature,
554 the program interruption transaction diagnostic block (TDB) is now
555 represented as a number of additional "registers" in GDB.
561 The vCont packet supports a new 'r' action, that tells the remote
562 stub to step through an address range itself, without GDB
563 involvemement at each single-step.
565 qXfer:libraries-svr4:read's annex
566 The previously unused annex of the qXfer:libraries-svr4:read packet
567 is now used to support passing an argument list. The remote stub
568 reports support for this argument list to GDB's qSupported query.
569 The defined arguments are "start" and "prev", used to reduce work
570 necessary for library list updating, resulting in significant
573 * New features in the GDB remote stub, GDBserver
575 ** GDBserver now supports target-assisted range stepping. Currently
576 enabled on x86/x86_64 GNU/Linux targets.
578 ** GDBserver now adds element 'tvar' in the XML in the reply to
579 'qXfer:traceframe-info:read'. It has the id of the collected
580 trace state variables.
582 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
585 * New 'z' formatter for printing and examining memory, this displays the
586 value as hexadecimal zero padded on the left to the size of the type.
588 * GDB can now use Windows x64 unwinding data.
590 * The "set remotebaud" command has been replaced by "set serial baud".
591 Similarly, "show remotebaud" has been replaced by "show serial baud".
592 The "set remotebaud" and "show remotebaud" commands are still available
593 to provide backward compatibility with older versions of GDB.
595 *** Changes in GDB 7.6
597 * Target record has been renamed to record-full.
598 Record/replay is now enabled with the "record full" command.
599 This also affects settings that are associated with full record/replay
600 that have been moved from "set/show record" to "set/show record full":
602 set|show record full insn-number-max
603 set|show record full stop-at-limit
604 set|show record full memory-query
606 * A new record target "record-btrace" has been added. The new target
607 uses hardware support to record the control-flow of a process. It
608 does not support replaying the execution, but it implements the
609 below new commands for investigating the recorded execution log.
610 This new recording method can be enabled using:
614 The "record-btrace" target is only available on Intel Atom processors
615 and requires a Linux kernel 2.6.32 or later.
617 * Two new commands have been added for record/replay to give information
618 about the recorded execution without having to replay the execution.
619 The commands are only supported by "record btrace".
621 record instruction-history prints the execution history at
622 instruction granularity
624 record function-call-history prints the execution history at
627 * New native configurations
629 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
630 FreeBSD/powerpc powerpc*-*-freebsd
631 x86_64/Cygwin x86_64-*-cygwin*
632 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
636 ARM AArch64 aarch64*-*-elf
637 ARM AArch64 GNU/Linux aarch64*-*-linux
638 Lynx 178 PowerPC powerpc-*-lynx*178
639 x86_64/Cygwin x86_64-*-cygwin*
640 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
642 * If the configured location of system.gdbinit file (as given by the
643 --with-system-gdbinit option at configure time) is in the
644 data-directory (as specified by --with-gdb-datadir at configure
645 time) or in one of its subdirectories, then GDB will look for the
646 system-wide init file in the directory specified by the
647 --data-directory command-line option.
649 * New command line options:
651 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
652 other initialization files, unlike -nx which disables all of them.
654 * Removed command line options
656 -epoch This was used by the gdb mode in Epoch, an ancient fork of
659 * The 'ptype' and 'whatis' commands now accept an argument to control
662 * 'info proc' now works on some core files.
666 ** Vectors can be created with gdb.Type.vector.
668 ** Python's atexit.register now works in GDB.
670 ** Types can be pretty-printed via a Python API.
672 ** Python 3 is now supported (in addition to Python 2.4 or later)
674 ** New class gdb.Architecture exposes GDB's internal representation
675 of architecture in the Python API.
677 ** New method Frame.architecture returns the gdb.Architecture object
678 corresponding to the frame's architecture.
680 * New Python-based convenience functions:
682 ** $_memeq(buf1, buf2, length)
683 ** $_streq(str1, str2)
685 ** $_regex(str, regex)
687 * The 'cd' command now defaults to using '~' (the home directory) if not
690 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
691 default for GCC since November 2000.
693 * The command 'forward-search' can now be abbreviated as 'fo'.
695 * The command 'info tracepoints' can now display 'installed on target'
696 or 'not installed on target' for each non-pending location of tracepoint.
698 * New configure options
700 --enable-libmcheck/--disable-libmcheck
701 By default, development versions are built with -lmcheck on hosts
702 that support it, in order to help track memory corruption issues.
703 Release versions, on the other hand, are built without -lmcheck
704 by default. The --enable-libmcheck/--disable-libmcheck configure
705 options allow the user to override that default.
706 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
707 This configure option allows the user to build GDB with
708 libbabeltrace using which GDB can read Common Trace Format data.
710 * New commands (for set/show, see "New options" below)
713 Catch signals. This is similar to "handle", but allows commands and
714 conditions to be attached.
717 List the BFDs known to GDB.
719 python-interactive [command]
721 Start a Python interactive prompt, or evaluate the optional command
722 and print the result of expressions.
725 "py" is a new alias for "python".
727 enable type-printer [name]...
728 disable type-printer [name]...
729 Enable or disable type printers.
733 ** For the Renesas Super-H architecture, the "regs" command has been removed
734 (has been deprecated in GDB 7.5), and "info all-registers" should be used
739 set print type methods (on|off)
740 show print type methods
741 Control whether method declarations are displayed by "ptype".
742 The default is to show them.
744 set print type typedefs (on|off)
745 show print type typedefs
746 Control whether typedef definitions are displayed by "ptype".
747 The default is to show them.
749 set filename-display basename|relative|absolute
750 show filename-display
751 Control the way in which filenames is displayed.
752 The default is "relative", which preserves previous behavior.
754 set trace-buffer-size
755 show trace-buffer-size
756 Request target to change the size of trace buffer.
758 set remote trace-buffer-size-packet auto|on|off
759 show remote trace-buffer-size-packet
760 Control the use of the remote protocol `QTBuffer:size' packet.
764 Control display of debugging messages related to ARM AArch64.
767 set debug coff-pe-read
768 show debug coff-pe-read
769 Control display of debugging messages related to reading of COFF/PE
774 Control display of debugging messages related to Mach-O symbols
777 set debug notification
778 show debug notification
779 Control display of debugging info for async remote notification.
783 ** Command parameter changes are now notified using new async record
784 "=cmd-param-changed".
785 ** Trace frame changes caused by command "tfind" are now notified using
786 new async record "=traceframe-changed".
787 ** The creation, deletion and modification of trace state variables
788 are now notified using new async records "=tsv-created",
789 "=tsv-deleted" and "=tsv-modified".
790 ** The start and stop of process record are now notified using new
791 async record "=record-started" and "=record-stopped".
792 ** Memory changes are now notified using new async record
794 ** The data-disassemble command response will include a "fullname" field
795 containing the absolute file name when source has been requested.
796 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
797 command, to allow pattern filling of memory areas.
798 ** New commands "-catch-load"/"-catch-unload" added for intercepting
799 library load/unload events.
800 ** The response to breakpoint commands and breakpoint async records
801 includes an "installed" field containing a boolean state about each
802 non-pending tracepoint location is whether installed on target or not.
803 ** Output of the "-trace-status" command includes a "trace-file" field
804 containing the name of the trace file being examined. This field is
805 optional, and only present when examining a trace file.
806 ** The "fullname" field is now always present along with the "file" field,
807 even if the file cannot be found by GDB.
809 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
810 You must have the LZMA library available when configuring GDB for this
811 feature to be enabled. For more information, see:
812 http://fedoraproject.org/wiki/Features/MiniDebugInfo
817 Set the size of trace buffer. The remote stub reports support for this
818 packet to gdb's qSupported query.
821 Enable Branch Trace Store (BTS)-based branch tracing for the current
822 thread. The remote stub reports support for this packet to gdb's
826 Disable branch tracing for the current thread. The remote stub reports
827 support for this packet to gdb's qSupported query.
830 Read the traced branches for the current thread. The remote stub
831 reports support for this packet to gdb's qSupported query.
833 *** Changes in GDB 7.5
835 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
836 for more x32 ABI info.
838 * GDB now supports access to MIPS DSP registers on Linux targets.
840 * GDB now supports debugging microMIPS binaries.
842 * The "info os" command on GNU/Linux can now display information on
843 several new classes of objects managed by the operating system:
844 "info os procgroups" lists process groups
845 "info os files" lists file descriptors
846 "info os sockets" lists internet-domain sockets
847 "info os shm" lists shared-memory regions
848 "info os semaphores" lists semaphores
849 "info os msg" lists message queues
850 "info os modules" lists loaded kernel modules
852 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
853 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
854 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
855 options and inspect the probe arguments using the new $_probe_arg family
856 of convenience variables. You can obtain more information about SystemTap
857 in <http://sourceware.org/systemtap/>.
859 * GDB now supports reversible debugging on ARM, it allows you to
860 debug basic ARM and THUMB instructions, and provides
861 record/replay support.
863 * The option "symbol-reloading" has been deleted as it is no longer used.
867 ** GDB commands implemented in Python can now be put in command class
870 ** The "maint set python print-stack on|off" is now deleted.
872 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
873 apply "flag enum"-style pretty-printing to any enum.
875 ** gdb.lookup_symbol can now work when there is no current frame.
877 ** gdb.Symbol now has a 'line' attribute, holding the line number in
878 the source at which the symbol was defined.
880 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
881 method 'value'. The former indicates whether the symbol needs a
882 frame in order to compute its value, and the latter computes the
885 ** A new method 'referenced_value' on gdb.Value objects which can
886 dereference pointer as well as C++ reference values.
888 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
889 which return the global and static blocks (as gdb.Block objects),
890 of the underlying symbol table, respectively.
892 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
893 object associated with a PC value.
895 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
896 of the address range occupied by code for the current source line.
898 * Go language support.
899 GDB now supports debugging programs written in the Go programming
902 * GDBserver now supports stdio connections.
903 E.g. (gdb) target remote | ssh myhost gdbserver - hello
905 * The binary "gdbtui" can no longer be built or installed.
906 Use "gdb -tui" instead.
908 * GDB will now print "flag" enums specially. A flag enum is one where
909 all the enumerator values have no bits in common when pairwise
910 "and"ed. When printing a value whose type is a flag enum, GDB will
911 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
912 (gdb) print (enum E) 3
915 * The filename part of a linespec will now match trailing components
916 of a source file name. For example, "break gcc/expr.c:1000" will
917 now set a breakpoint in build/gcc/expr.c, but not
920 * The "info proc" and "generate-core-file" commands will now also
921 work on remote targets connected to GDBserver on Linux.
923 * The command "info catch" has been removed. It has been disabled
926 * The "catch exception" and "catch assert" commands now accept
927 a condition at the end of the command, much like the "break"
928 command does. For instance:
930 (gdb) catch exception Constraint_Error if Barrier = True
932 Previously, it was possible to add a condition to such catchpoints,
933 but it had to be done as a second step, after the catchpoint had been
934 created, using the "condition" command.
936 * The "info static-tracepoint-marker" command will now also work on
937 native Linux targets with in-process agent.
939 * GDB can now set breakpoints on inlined functions.
941 * The .gdb_index section has been updated to include symbols for
942 inlined functions. GDB will ignore older .gdb_index sections by
943 default, which could cause symbol files to be loaded more slowly
944 until their .gdb_index sections can be recreated. The new command
945 "set use-deprecated-index-sections on" will cause GDB to use any older
946 .gdb_index sections it finds. This will restore performance, but the
947 ability to set breakpoints on inlined functions will be lost in symbol
948 files with older .gdb_index sections.
950 The .gdb_index section has also been updated to record more information
951 about each symbol. This speeds up the "info variables", "info functions"
952 and "info types" commands when used with programs having the .gdb_index
953 section, as well as speeding up debugging with shared libraries using
954 the .gdb_index section.
956 * Ada support for GDB/MI Variable Objects has been added.
958 * GDB can now support 'breakpoint always-inserted mode' in 'record'
963 ** New command -info-os is the MI equivalent of "info os".
965 ** Output logs ("set logging" and related) now include MI output.
969 ** "set use-deprecated-index-sections on|off"
970 "show use-deprecated-index-sections on|off"
971 Controls the use of deprecated .gdb_index sections.
973 ** "catch load" and "catch unload" can be used to stop when a shared
974 library is loaded or unloaded, respectively.
976 ** "enable count" can be used to auto-disable a breakpoint after
979 ** "info vtbl" can be used to show the virtual method tables for
980 C++ and Java objects.
982 ** "explore" and its sub commands "explore value" and "explore type"
983 can be used to recursively explore values and types of
984 expressions. These commands are available only if GDB is
985 configured with '--with-python'.
987 ** "info auto-load" shows status of all kinds of auto-loaded files,
988 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
989 sequences of commands files, "info auto-load python-scripts"
990 shows status of auto-loading Python script files,
991 "info auto-load local-gdbinit" shows status of loading init file
992 (.gdbinit) from current directory and "info auto-load libthread-db" shows
993 status of inferior specific thread debugging shared library loading.
995 ** "info auto-load-scripts", "set auto-load-scripts on|off"
996 and "show auto-load-scripts" commands have been deprecated, use their
997 "info auto-load python-scripts", "set auto-load python-scripts on|off"
998 and "show auto-load python-scripts" counterparts instead.
1000 ** "dprintf location,format,args..." creates a dynamic printf, which
1001 is basically a breakpoint that does a printf and immediately
1002 resumes your program's execution, so it is like a printf that you
1003 can insert dynamically at runtime instead of at compiletime.
1005 ** "set print symbol"
1007 Controls whether GDB attempts to display the symbol, if any,
1008 corresponding to addresses it prints. This defaults to "on", but
1009 you can set it to "off" to restore GDB's previous behavior.
1011 * Deprecated commands
1013 ** For the Renesas Super-H architecture, the "regs" command has been
1014 deprecated, and "info all-registers" should be used instead.
1018 Renesas RL78 rl78-*-elf
1019 HP OpenVMS ia64 ia64-hp-openvms*
1021 * GDBserver supports evaluation of breakpoint conditions. When
1022 support is advertised by GDBserver, GDB may be told to send the
1023 breakpoint conditions in bytecode form to GDBserver. GDBserver
1024 will only report the breakpoint trigger to GDB when its condition
1029 set mips compression
1030 show mips compression
1031 Select the compressed ISA encoding used in functions that have no symbol
1032 information available. The encoding can be set to either of:
1035 and is updated automatically from ELF file flags if available.
1037 set breakpoint condition-evaluation
1038 show breakpoint condition-evaluation
1039 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1040 GDBserver ("target"). Default option "auto" chooses the most efficient
1042 This option can improve debugger efficiency depending on the speed of the
1046 Disable auto-loading globally.
1049 Show auto-loading setting of all kinds of auto-loaded files.
1051 set auto-load gdb-scripts on|off
1052 show auto-load gdb-scripts
1053 Control auto-loading of GDB canned sequences of commands files.
1055 set auto-load python-scripts on|off
1056 show auto-load python-scripts
1057 Control auto-loading of Python script files.
1059 set auto-load local-gdbinit on|off
1060 show auto-load local-gdbinit
1061 Control loading of init file (.gdbinit) from current directory.
1063 set auto-load libthread-db on|off
1064 show auto-load libthread-db
1065 Control auto-loading of inferior specific thread debugging shared library.
1067 set auto-load scripts-directory <dir1>[:<dir2>...]
1068 show auto-load scripts-directory
1069 Set a list of directories from which to load auto-loaded scripts.
1070 Automatically loaded Python scripts and GDB scripts are located in one
1071 of the directories listed by this option.
1072 The delimiter (':' above) may differ according to the host platform.
1074 set auto-load safe-path <dir1>[:<dir2>...]
1075 show auto-load safe-path
1076 Set a list of directories from which it is safe to auto-load files.
1077 The delimiter (':' above) may differ according to the host platform.
1079 set debug auto-load on|off
1080 show debug auto-load
1081 Control display of debugging info for auto-loading the files above.
1083 set dprintf-style gdb|call|agent
1085 Control the way in which a dynamic printf is performed; "gdb"
1086 requests a GDB printf command, while "call" causes dprintf to call a
1087 function in the inferior. "agent" requests that the target agent
1088 (such as GDBserver) do the printing.
1090 set dprintf-function <expr>
1091 show dprintf-function
1092 set dprintf-channel <expr>
1093 show dprintf-channel
1094 Set the function and optional first argument to the call when using
1095 the "call" style of dynamic printf.
1097 set disconnected-dprintf on|off
1098 show disconnected-dprintf
1099 Control whether agent-style dynamic printfs continue to be in effect
1100 after GDB disconnects.
1102 * New configure options
1104 --with-auto-load-dir
1105 Configure default value for the 'set auto-load scripts-directory'
1106 setting above. It defaults to '$debugdir:$datadir/auto-load',
1107 $debugdir representing global debugging info directories (available
1108 via 'show debug-file-directory') and $datadir representing GDB's data
1109 directory (available via 'show data-directory').
1111 --with-auto-load-safe-path
1112 Configure default value for the 'set auto-load safe-path' setting
1113 above. It defaults to the --with-auto-load-dir setting.
1115 --without-auto-load-safe-path
1116 Set 'set auto-load safe-path' to '/', effectively disabling this
1119 * New remote packets
1121 z0/z1 conditional breakpoints extension
1123 The z0/z1 breakpoint insertion packets have been extended to carry
1124 a list of conditional expressions over to the remote stub depending on the
1125 condition evaluation mode. The use of this extension can be controlled
1126 via the "set remote conditional-breakpoints-packet" command.
1130 Specify the signals which the remote stub may pass to the debugged
1131 program without GDB involvement.
1133 * New command line options
1135 --init-command=FILE, -ix Like --command, -x but execute it
1136 before loading inferior.
1137 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1138 execute it before loading inferior.
1140 *** Changes in GDB 7.4
1142 * GDB now handles ambiguous linespecs more consistently; the existing
1143 FILE:LINE support has been expanded to other types of linespecs. A
1144 breakpoint will now be set on all matching locations in all
1145 inferiors, and locations will be added or removed according to
1148 * GDB now allows you to skip uninteresting functions and files when
1149 stepping with the "skip function" and "skip file" commands.
1151 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1152 and "show remote hardware-watchpoint-length-limit". These allows to
1153 set or show the maximum length limit (in bytes) of a remote
1154 target hardware watchpoint.
1156 This allows e.g. to use "unlimited" hardware watchpoints with the
1157 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1158 watchpoints are slower than real hardware watchpoints but are
1159 significantly faster than gdb software watchpoints.
1163 ** The register_pretty_printer function in module gdb.printing now takes
1164 an optional `replace' argument. If True, the new printer replaces any
1167 ** The "maint set python print-stack on|off" command has been
1168 deprecated and will be deleted in GDB 7.5.
1169 A new command: "set python print-stack none|full|message" has
1170 replaced it. Additionally, the default for "print-stack" is
1171 now "message", which just prints the error message without
1174 ** A prompt substitution hook (prompt_hook) is now available to the
1177 ** A new Python module, gdb.prompt has been added to the GDB Python
1178 modules library. This module provides functionality for
1179 escape sequences in prompts (used by set/show
1180 extended-prompt). These escape sequences are replaced by their
1181 corresponding value.
1183 ** Python commands and convenience-functions located in
1184 'data-directory'/python/gdb/command and
1185 'data-directory'/python/gdb/function are now automatically loaded
1188 ** Blocks now provide four new attributes. global_block and
1189 static_block will return the global and static blocks
1190 respectively. is_static and is_global are boolean attributes
1191 that indicate if the block is one of those two types.
1193 ** Symbols now provide the "type" attribute, the type of the symbol.
1195 ** The "gdb.breakpoint" function has been deprecated in favor of
1198 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1199 of a function. This class is based on the "finish" command
1200 available in the CLI.
1202 ** Type objects for struct and union types now allow access to
1203 the fields using standard Python dictionary (mapping) methods.
1204 For example, "some_type['myfield']" now works, as does
1205 "some_type.items()".
1207 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1210 ** A new function, "deep_items" has been added to the gdb.types
1211 module in the GDB Python modules library. This function returns
1212 an iterator over the fields of a struct or union type. Unlike
1213 the standard Python "iteritems" method, it will recursively traverse
1214 any anonymous fields.
1218 ** "*stopped" events can report several new "reason"s, such as
1221 ** Breakpoint changes are now notified using new async records, like
1222 "=breakpoint-modified".
1224 ** New command -ada-task-info.
1226 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1227 $sdir specifies the default system locations of shared libraries.
1228 $pdir specifies the directory where the libpthread used by the application
1231 GDB no longer looks in $sdir and $pdir after it has searched the directories
1232 mentioned in libthread-db-search-path. If you want to search those
1233 directories, they must be specified in libthread-db-search-path.
1234 The default value of libthread-db-search-path on GNU/Linux and Solaris
1235 systems is now "$sdir:$pdir".
1237 $pdir is not supported by gdbserver, it is currently ignored.
1238 $sdir is supported by gdbserver.
1240 * New configure option --with-iconv-bin.
1241 When using the internationalization support like the one in the GNU C
1242 library, GDB will invoke the "iconv" program to get a list of supported
1243 character sets. If this program lives in a non-standard location, one can
1244 use this option to specify where to find it.
1246 * When natively debugging programs on PowerPC BookE processors running
1247 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1248 watchpoints, which specify a mask in addition to an address to watch.
1249 The mask specifies that some bits of an address (the bits which are
1250 reset in the mask) should be ignored when matching the address accessed
1251 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1252 section in the user manual for more details.
1254 * The new option --once causes GDBserver to stop listening for connections once
1255 the first connection is made. The listening port used by GDBserver will
1256 become available after that.
1258 * New commands "info macros" and "alias" have been added.
1260 * New function parameters suffix @entry specifies value of function parameter
1261 at the time the function got called. Entry values are available only since
1267 "!" is now an alias of the "shell" command.
1268 Note that no space is needed between "!" and SHELL COMMAND.
1272 watch EXPRESSION mask MASK_VALUE
1273 The watch command now supports the mask argument which allows creation
1274 of masked watchpoints, if the current architecture supports this feature.
1276 info auto-load-scripts [REGEXP]
1277 This command was formerly named "maintenance print section-scripts".
1278 It is now generally useful and is no longer a maintenance-only command.
1280 info macro [-all] [--] MACRO
1281 The info macro command has new options `-all' and `--'. The first for
1282 printing all definitions of a macro. The second for explicitly specifying
1283 the end of arguments and the beginning of the macro name in case the macro
1284 name starts with a hyphen.
1286 collect[/s] EXPRESSIONS
1287 The tracepoint collect command now takes an optional modifier "/s"
1288 that directs it to dereference pointer-to-character types and
1289 collect the bytes of memory up to a zero byte. The behavior is
1290 similar to what you see when you use the regular print command on a
1291 string. An optional integer following the "/s" sets a bound on the
1292 number of bytes that will be collected.
1295 The trace start command now interprets any supplied arguments as a
1296 note to be recorded with the trace run, with an effect similar to
1297 setting the variable trace-notes.
1300 The trace stop command now interprets any arguments as a note to be
1301 mentioned along with the tstatus report that the trace was stopped
1302 with a command. The effect is similar to setting the variable
1305 * Tracepoints can now be enabled and disabled at any time after a trace
1306 experiment has been started using the standard "enable" and "disable"
1307 commands. It is now possible to start a trace experiment with no enabled
1308 tracepoints; GDB will display a warning, but will allow the experiment to
1309 begin, assuming that tracepoints will be enabled as needed while the trace
1312 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1313 locations with 4-byte instructions, when they were previously
1314 limited to locations with instructions of 5 bytes or longer.
1318 set debug dwarf2-read
1319 show debug dwarf2-read
1320 Turns on or off display of debugging messages related to reading
1321 DWARF debug info. The default is off.
1323 set debug symtab-create
1324 show debug symtab-create
1325 Turns on or off display of debugging messages related to symbol table
1326 creation. The default is off.
1329 show extended-prompt
1330 Set the GDB prompt, and allow escape sequences to be inserted to
1331 display miscellaneous information (see 'help set extended-prompt'
1332 for the list of sequences). This prompt (and any information
1333 accessed through the escape sequences) is updated every time the
1334 prompt is displayed.
1336 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1337 show print entry-values
1338 Set printing of frame argument values at function entry. In some cases
1339 GDB can determine the value of function argument which was passed by the
1340 function caller, even if the value was modified inside the called function.
1342 set debug entry-values
1343 show debug entry-values
1344 Control display of debugging info for determining frame argument values at
1345 function entry and virtual tail call frames.
1347 set basenames-may-differ
1348 show basenames-may-differ
1349 Set whether a source file may have multiple base names.
1350 (A "base name" is the name of a file with the directory part removed.
1351 Example: The base name of "/home/user/hello.c" is "hello.c".)
1352 If set, GDB will canonicalize file names (e.g., expand symlinks)
1353 before comparing them. Canonicalization is an expensive operation,
1354 but it allows the same file be known by more than one base name.
1355 If not set (the default), all source files are assumed to have just
1356 one base name, and gdb will do file name comparisons more efficiently.
1362 Set a user name and notes for the current and any future trace runs.
1363 This is useful for long-running and/or disconnected traces, to
1364 inform others (or yourself) as to who is running the trace, supply
1365 contact information, or otherwise explain what is going on.
1367 set trace-stop-notes
1368 show trace-stop-notes
1369 Set a note attached to the trace run, that is displayed when the
1370 trace has been stopped by a tstop command. This is useful for
1371 instance as an explanation, if you are stopping a trace run that was
1372 started by someone else.
1374 * New remote packets
1378 Dynamically enable a tracepoint in a started trace experiment.
1382 Dynamically disable a tracepoint in a started trace experiment.
1386 Set the user and notes of the trace run.
1390 Query the current status of a tracepoint.
1394 Query the minimum length of instruction at which a fast tracepoint may
1397 * Dcache size (number of lines) and line-size are now runtime-configurable
1398 via "set dcache line" and "set dcache line-size" commands.
1402 Texas Instruments TMS320C6x tic6x-*-*
1406 Renesas RL78 rl78-*-elf
1408 *** Changes in GDB 7.3.1
1410 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1412 *** Changes in GDB 7.3
1414 * GDB has a new command: "thread find [REGEXP]".
1415 It finds the thread id whose name, target id, or thread extra info
1416 matches the given regular expression.
1418 * The "catch syscall" command now works on mips*-linux* targets.
1420 * The -data-disassemble MI command now supports modes 2 and 3 for
1421 dumping the instruction opcodes.
1423 * New command line options
1425 -data-directory DIR Specify DIR as the "data-directory".
1426 This is mostly for testing purposes.
1428 * The "maint set python auto-load on|off" command has been renamed to
1429 "set auto-load-scripts on|off".
1431 * GDB has a new command: "set directories".
1432 It is like the "dir" command except that it replaces the
1433 source path list instead of augmenting it.
1435 * GDB now understands thread names.
1437 On GNU/Linux, "info threads" will display the thread name as set by
1438 prctl or pthread_setname_np.
1440 There is also a new command, "thread name", which can be used to
1441 assign a name internally for GDB to display.
1444 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1445 has been integrated into GDB.
1449 ** The function gdb.Write now accepts an optional keyword 'stream'.
1450 This keyword, when provided, will direct the output to either
1451 stdout, stderr, or GDB's logging output.
1453 ** Parameters can now be be sub-classed in Python, and in particular
1454 you may implement the get_set_doc and get_show_doc functions.
1455 This improves how Parameter set/show documentation is processed
1456 and allows for more dynamic content.
1458 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1459 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1460 have an is_valid method.
1462 ** Breakpoints can now be sub-classed in Python, and in particular
1463 you may implement a 'stop' function that is executed each time
1464 the inferior reaches that breakpoint.
1466 ** New function gdb.lookup_global_symbol looks up a global symbol.
1468 ** GDB values in Python are now callable if the value represents a
1469 function. For example, if 'some_value' represents a function that
1470 takes two integer parameters and returns a value, you can call
1471 that function like so:
1473 result = some_value (10,20)
1475 ** Module gdb.types has been added.
1476 It contains a collection of utilities for working with gdb.Types objects:
1477 get_basic_type, has_field, make_enum_dict.
1479 ** Module gdb.printing has been added.
1480 It contains utilities for writing and registering pretty-printers.
1481 New classes: PrettyPrinter, SubPrettyPrinter,
1482 RegexpCollectionPrettyPrinter.
1483 New function: register_pretty_printer.
1485 ** New commands "info pretty-printers", "enable pretty-printer" and
1486 "disable pretty-printer" have been added.
1488 ** gdb.parameter("directories") is now available.
1490 ** New function gdb.newest_frame returns the newest frame in the
1493 ** The gdb.InferiorThread class has a new "name" attribute. This
1494 holds the thread's name.
1496 ** Python Support for Inferior events.
1497 Python scripts can add observers to be notified of events
1498 occurring in the process being debugged.
1499 The following events are currently supported:
1500 - gdb.events.cont Continue event.
1501 - gdb.events.exited Inferior exited event.
1502 - gdb.events.stop Signal received, and Breakpoint hit events.
1506 ** GDB now puts template parameters in scope when debugging in an
1507 instantiation. For example, if you have:
1509 template<int X> int func (void) { return X; }
1511 then if you step into func<5>, "print X" will show "5". This
1512 feature requires proper debuginfo support from the compiler; it
1513 was added to GCC 4.5.
1515 ** The motion commands "next", "finish", "until", and "advance" now
1516 work better when exceptions are thrown. In particular, GDB will
1517 no longer lose control of the inferior; instead, the GDB will
1518 stop the inferior at the point at which the exception is caught.
1519 This functionality requires a change in the exception handling
1520 code that was introduced in GCC 4.5.
1522 * GDB now follows GCC's rules on accessing volatile objects when
1523 reading or writing target state during expression evaluation.
1524 One notable difference to prior behavior is that "print x = 0"
1525 no longer generates a read of x; the value of the assignment is
1526 now always taken directly from the value being assigned.
1528 * GDB now has some support for using labels in the program's source in
1529 linespecs. For instance, you can use "advance label" to continue
1530 execution to a label.
1532 * GDB now has support for reading and writing a new .gdb_index
1533 section. This section holds a fast index of DWARF debugging
1534 information and can be used to greatly speed up GDB startup and
1535 operation. See the documentation for `save gdb-index' for details.
1537 * The "watch" command now accepts an optional "-location" argument.
1538 When used, this causes GDB to watch the memory referred to by the
1539 expression. Such a watchpoint is never deleted due to it going out
1542 * GDB now supports thread debugging of core dumps on GNU/Linux.
1544 GDB now activates thread debugging using the libthread_db library
1545 when debugging GNU/Linux core dumps, similarly to when debugging
1546 live processes. As a result, when debugging a core dump file, GDB
1547 is now able to display pthread_t ids of threads. For example, "info
1548 threads" shows the same output as when debugging the process when it
1549 was live. In earlier releases, you'd see something like this:
1552 * 1 LWP 6780 main () at main.c:10
1554 While now you see this:
1557 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1559 It is also now possible to inspect TLS variables when debugging core
1562 When debugging a core dump generated on a machine other than the one
1563 used to run GDB, you may need to point GDB at the correct
1564 libthread_db library with the "set libthread-db-search-path"
1565 command. See the user manual for more details on this command.
1567 * When natively debugging programs on PowerPC BookE processors running
1568 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1569 which stop execution of the inferior whenever it executes an instruction
1570 at any address within the specified range. See the "PowerPC Embedded"
1571 section in the user manual for more details.
1573 * New features in the GDB remote stub, GDBserver
1575 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1576 and i686 LynxOS (version 5.x).
1578 ** GDBserver is now supported on Blackfin Linux.
1580 * New native configurations
1582 ia64 HP-UX ia64-*-hpux*
1586 Analog Devices, Inc. Blackfin Processor bfin-*
1588 * Ada task switching is now supported on sparc-elf targets when
1589 debugging a program using the Ravenscar Profile. For more information,
1590 see the "Tasking Support when using the Ravenscar Profile" section
1591 in the GDB user manual.
1593 * Guile support was removed.
1595 * New features in the GNU simulator
1597 ** The --map-info flag lists all known core mappings.
1599 ** CFI flashes may be simulated via the "cfi" device.
1601 *** Changes in GDB 7.2
1603 * Shared library support for remote targets by default
1605 When GDB is configured for a generic, non-OS specific target, like
1606 for example, --target=arm-eabi or one of the many *-*-elf targets,
1607 GDB now queries remote stubs for loaded shared libraries using the
1608 `qXfer:libraries:read' packet. Previously, shared library support
1609 was always disabled for such configurations.
1613 ** Argument Dependent Lookup (ADL)
1615 In C++ ADL lookup directs function search to the namespaces of its
1616 arguments even if the namespace has not been imported.
1626 Here the compiler will search for `foo' in the namespace of 'b'
1627 and find A::foo. GDB now supports this. This construct is commonly
1628 used in the Standard Template Library for operators.
1630 ** Improved User Defined Operator Support
1632 In addition to member operators, GDB now supports lookup of operators
1633 defined in a namespace and imported with a `using' directive, operators
1634 defined in the global scope, operators imported implicitly from an
1635 anonymous namespace, and the ADL operators mentioned in the previous
1637 GDB now also supports proper overload resolution for all the previously
1638 mentioned flavors of operators.
1640 ** static const class members
1642 Printing of static const class members that are initialized in the
1643 class definition has been fixed.
1645 * Windows Thread Information Block access.
1647 On Windows targets, GDB now supports displaying the Windows Thread
1648 Information Block (TIB) structure. This structure is visible either
1649 by using the new command `info w32 thread-information-block' or, by
1650 dereferencing the new convenience variable named `$_tlb', a
1651 thread-specific pointer to the TIB. This feature is also supported
1652 when remote debugging using GDBserver.
1654 * Static tracepoints
1656 Static tracepoints are calls in the user program into a tracing
1657 library. One such library is a port of the LTTng kernel tracer to
1658 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1659 When debugging with GDBserver, GDB now supports combining the GDB
1660 tracepoint machinery with such libraries. For example: the user can
1661 use GDB to probe a static tracepoint marker (a call from the user
1662 program into the tracing library) with the new "strace" command (see
1663 "New commands" below). This creates a "static tracepoint" in the
1664 breakpoint list, that can be manipulated with the same feature set
1665 as fast and regular tracepoints. E.g., collect registers, local and
1666 global variables, collect trace state variables, and define
1667 tracepoint conditions. In addition, the user can collect extra
1668 static tracepoint marker specific data, by collecting the new
1669 $_sdata internal variable. When analyzing the trace buffer, you can
1670 inspect $_sdata like any other variable available to GDB. For more
1671 information, see the "Tracepoints" chapter in GDB user manual. New
1672 remote packets have been defined to support static tracepoints, see
1673 the "New remote packets" section below.
1675 * Better reconstruction of tracepoints after disconnected tracing
1677 GDB will attempt to download the original source form of tracepoint
1678 definitions when starting a trace run, and then will upload these
1679 upon reconnection to the target, resulting in a more accurate
1680 reconstruction of the tracepoints that are in use on the target.
1684 You can now exercise direct control over the ways that GDB can
1685 affect your program. For instance, you can disallow the setting of
1686 breakpoints, so that the program can run continuously (assuming
1687 non-stop mode). In addition, the "observer" variable is available
1688 to switch all of the different controls; in observer mode, GDB
1689 cannot affect the target's behavior at all, which is useful for
1690 tasks like diagnosing live systems in the field.
1692 * The new convenience variable $_thread holds the number of the
1695 * New remote packets
1699 Return the address of the Windows Thread Information Block of a given thread.
1703 In response to several of the tracepoint packets, the target may now
1704 also respond with a number of intermediate `qRelocInsn' request
1705 packets before the final result packet, to have GDB handle
1706 relocating an instruction to execute at a different address. This
1707 is particularly useful for stubs that support fast tracepoints. GDB
1708 reports support for this feature in the qSupported packet.
1712 List static tracepoint markers in the target program.
1716 List static tracepoint markers at a given address in the target
1719 qXfer:statictrace:read
1721 Read the static trace data collected (by a `collect $_sdata'
1722 tracepoint action). The remote stub reports support for this packet
1723 to gdb's qSupported query.
1727 Send the current settings of GDB's permission flags.
1731 Send part of the source (textual) form of a tracepoint definition,
1732 which includes location, conditional, and action list.
1734 * The source command now accepts a -s option to force searching for the
1735 script in the source search path even if the script name specifies
1738 * New features in the GDB remote stub, GDBserver
1740 - GDBserver now support tracepoints (including fast tracepoints, and
1741 static tracepoints). The feature is currently supported by the
1742 i386-linux and amd64-linux builds. See the "Tracepoints support
1743 in gdbserver" section in the manual for more information.
1745 GDBserver JIT compiles the tracepoint's conditional agent
1746 expression bytecode into native code whenever possible for low
1747 overhead dynamic tracepoints conditionals. For such tracepoints,
1748 an expression that examines program state is evaluated when the
1749 tracepoint is reached, in order to determine whether to capture
1750 trace data. If the condition is simple and false, processing the
1751 tracepoint finishes very quickly and no data is gathered.
1753 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1754 for static tracepoints support.
1756 - GDBserver now supports x86_64 Windows 64-bit debugging.
1758 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1759 it understands register description.
1761 * The --batch flag now disables pagination and queries.
1763 * X86 general purpose registers
1765 GDB now supports reading/writing byte, word and double-word x86
1766 general purpose registers directly. This means you can use, say,
1767 $ah or $ax to refer, respectively, to the byte register AH and
1768 16-bit word register AX that are actually portions of the 32-bit
1769 register EAX or 64-bit register RAX.
1771 * The `commands' command now accepts a range of breakpoints to modify.
1772 A plain `commands' following a command that creates multiple
1773 breakpoints affects all the breakpoints set by that command. This
1774 applies to breakpoints set by `rbreak', and also applies when a
1775 single `break' command creates multiple breakpoints (e.g.,
1776 breakpoints on overloaded c++ functions).
1778 * The `rbreak' command now accepts a filename specification as part of
1779 its argument, limiting the functions selected by the regex to those
1780 in the specified file.
1782 * Support for remote debugging Windows and SymbianOS shared libraries
1783 from Unix hosts has been improved. Non Windows GDB builds now can
1784 understand target reported file names that follow MS-DOS based file
1785 system semantics, such as file names that include drive letters and
1786 use the backslash character as directory separator. This makes it
1787 possible to transparently use the "set sysroot" and "set
1788 solib-search-path" on Unix hosts to point as host copies of the
1789 target's shared libraries. See the new command "set
1790 target-file-system-kind" described below, and the "Commands to
1791 specify files" section in the user manual for more information.
1795 eval template, expressions...
1796 Convert the values of one or more expressions under the control
1797 of the string template to a command line, and call it.
1799 set target-file-system-kind unix|dos-based|auto
1800 show target-file-system-kind
1801 Set or show the assumed file system kind for target reported file
1804 save breakpoints <filename>
1805 Save all current breakpoint definitions to a file suitable for use
1806 in a later debugging session. To read the saved breakpoint
1807 definitions, use the `source' command.
1809 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1812 info static-tracepoint-markers
1813 Display information about static tracepoint markers in the target.
1815 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1816 Define a static tracepoint by probing a marker at the given
1817 function, line, address, or marker ID.
1821 Enable and disable observer mode.
1823 set may-write-registers on|off
1824 set may-write-memory on|off
1825 set may-insert-breakpoints on|off
1826 set may-insert-tracepoints on|off
1827 set may-insert-fast-tracepoints on|off
1828 set may-interrupt on|off
1829 Set individual permissions for GDB effects on the target. Note that
1830 some of these settings can have undesirable or surprising
1831 consequences, particularly when changed in the middle of a session.
1832 For instance, disabling the writing of memory can prevent
1833 breakpoints from being inserted, cause single-stepping to fail, or
1834 even crash your program, if you disable after breakpoints have been
1835 inserted. However, GDB should not crash.
1837 set record memory-query on|off
1838 show record memory-query
1839 Control whether to stop the inferior if memory changes caused
1840 by an instruction cannot be recorded.
1845 The disassemble command now supports "start,+length" form of two arguments.
1849 ** GDB now provides a new directory location, called the python directory,
1850 where Python scripts written for GDB can be installed. The location
1851 of that directory is <data-directory>/python, where <data-directory>
1852 is the GDB data directory. For more details, see section `Scripting
1853 GDB using Python' in the manual.
1855 ** The GDB Python API now has access to breakpoints, symbols, symbol
1856 tables, program spaces, inferiors, threads and frame's code blocks.
1857 Additionally, GDB Parameters can now be created from the API, and
1858 manipulated via set/show in the CLI.
1860 ** New functions gdb.target_charset, gdb.target_wide_charset,
1861 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1863 ** New exception gdb.GdbError.
1865 ** Pretty-printers are now also looked up in the current program space.
1867 ** Pretty-printers can now be individually enabled and disabled.
1869 ** GDB now looks for names of Python scripts to auto-load in a
1870 special section named `.debug_gdb_scripts', in addition to looking
1871 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1873 * Tracepoint actions were unified with breakpoint commands. In particular,
1874 there are no longer differences in "info break" output for breakpoints and
1875 tracepoints and the "commands" command can be used for both tracepoints and
1876 regular breakpoints.
1880 ARM Symbian arm*-*-symbianelf*
1882 * D language support.
1883 GDB now supports debugging programs written in the D programming
1886 * GDB now supports the extended ptrace interface for PowerPC which is
1887 available since Linux kernel version 2.6.34. This automatically enables
1888 any hardware breakpoints and additional hardware watchpoints available in
1889 the processor. The old ptrace interface exposes just one hardware
1890 watchpoint and no hardware breakpoints.
1892 * GDB is now able to use the Data Value Compare (DVC) register available on
1893 embedded PowerPC processors to implement in hardware simple watchpoint
1894 conditions of the form:
1896 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1898 This works in native GDB running on Linux kernels with the extended ptrace
1899 interface mentioned above.
1901 *** Changes in GDB 7.1
1905 ** Namespace Support
1907 GDB now supports importing of namespaces in C++. This enables the
1908 user to inspect variables from imported namespaces. Support for
1909 namepace aliasing has also been added. So, if a namespace is
1910 aliased in the current scope (e.g. namepace C=A; ) the user can
1911 print variables using the alias (e.g. (gdb) print C::x).
1915 All known bugs relating to the printing of virtual base class were
1916 fixed. It is now possible to call overloaded static methods using a
1921 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1922 and reinterpret_cast<> are now handled by the C++ expression parser.
1926 Xilinx MicroBlaze microblaze-*-*
1931 Xilinx MicroBlaze microblaze
1934 * Multi-program debugging.
1936 GDB now has support for multi-program (a.k.a. multi-executable or
1937 multi-exec) debugging. This allows for debugging multiple inferiors
1938 simultaneously each running a different program under the same GDB
1939 session. See "Debugging Multiple Inferiors and Programs" in the
1940 manual for more information. This implied some user visible changes
1941 in the multi-inferior support. For example, "info inferiors" now
1942 lists inferiors that are not running yet or that have exited
1943 already. See also "New commands" and "New options" below.
1945 * New tracing features
1947 GDB's tracepoint facility now includes several new features:
1949 ** Trace state variables
1951 GDB tracepoints now include support for trace state variables, which
1952 are variables managed by the target agent during a tracing
1953 experiment. They are useful for tracepoints that trigger each
1954 other, so for instance one tracepoint can count hits in a variable,
1955 and then a second tracepoint has a condition that is true when the
1956 count reaches a particular value. Trace state variables share the
1957 $-syntax of GDB convenience variables, and can appear in both
1958 tracepoint actions and condition expressions. Use the "tvariable"
1959 command to create, and "info tvariables" to view; see "Trace State
1960 Variables" in the manual for more detail.
1964 GDB now includes an option for defining fast tracepoints, which
1965 targets may implement more efficiently, such as by installing a jump
1966 into the target agent rather than a trap instruction. The resulting
1967 speedup can be by two orders of magnitude or more, although the
1968 tradeoff is that some program locations on some target architectures
1969 might not allow fast tracepoint installation, for instance if the
1970 instruction to be replaced is shorter than the jump. To request a
1971 fast tracepoint, use the "ftrace" command, with syntax identical to
1972 the regular trace command.
1974 ** Disconnected tracing
1976 It is now possible to detach GDB from the target while it is running
1977 a trace experiment, then reconnect later to see how the experiment
1978 is going. In addition, a new variable disconnected-tracing lets you
1979 tell the target agent whether to continue running a trace if the
1980 connection is lost unexpectedly.
1984 GDB now has the ability to save the trace buffer into a file, and
1985 then use that file as a target, similarly to you can do with
1986 corefiles. You can select trace frames, print data that was
1987 collected in them, and use tstatus to display the state of the
1988 tracing run at the moment that it was saved. To create a trace
1989 file, use "tsave <filename>", and to use it, do "target tfile
1992 ** Circular trace buffer
1994 You can ask the target agent to handle the trace buffer as a
1995 circular buffer, discarding the oldest trace frames to make room for
1996 newer ones, by setting circular-trace-buffer to on. This feature may
1997 not be available for all target agents.
2002 The disassemble command, when invoked with two arguments, now requires
2003 the arguments to be comma-separated.
2006 The info variables command now displays variable definitions. Files
2007 which only declare a variable are not shown.
2010 The source command is now capable of sourcing Python scripts.
2011 This feature is dependent on the debugger being build with Python
2014 Related to this enhancement is also the introduction of a new command
2015 "set script-extension" (see below).
2017 * New commands (for set/show, see "New options" below)
2019 record save [<FILENAME>]
2020 Save a file (in core file format) containing the process record
2021 execution log for replay debugging at a later time.
2023 record restore <FILENAME>
2024 Restore the process record execution log that was saved at an
2025 earlier time, for replay debugging.
2027 add-inferior [-copies <N>] [-exec <FILENAME>]
2030 clone-inferior [-copies <N>] [ID]
2031 Make a new inferior ready to execute the same program another
2032 inferior has loaded.
2037 maint info program-spaces
2038 List the program spaces loaded into GDB.
2040 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2041 show remote interrupt-sequence
2042 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2043 as the sequence to the remote target in order to interrupt the execution.
2044 Ctrl-C is a default. Some system prefers BREAK which is high level of
2045 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2046 Magic SysRq g. It is BREAK signal and character 'g'.
2048 set remote interrupt-on-connect [on | off]
2049 show remote interrupt-on-connect
2050 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2051 remote target when gdb connects to it. This is needed when you debug
2054 set remotebreak [on | off]
2056 Deprecated. Use "set/show remote interrupt-sequence" instead.
2058 tvariable $NAME [ = EXP ]
2059 Create or modify a trace state variable.
2062 List trace state variables and their values.
2064 delete tvariable $NAME ...
2065 Delete one or more trace state variables.
2068 Evaluate the given expressions without collecting anything into the
2069 trace buffer. (Valid in tracepoint actions only.)
2071 ftrace FN / FILE:LINE / *ADDR
2072 Define a fast tracepoint at the given function, line, or address.
2074 * New expression syntax
2076 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2077 GDB now parses 0b101010 identically with 42.
2081 set follow-exec-mode new|same
2082 show follow-exec-mode
2083 Control whether GDB reuses the same inferior across an exec call or
2084 creates a new one. This is useful to be able to restart the old
2085 executable after the inferior having done an exec call.
2087 set default-collect EXPR, ...
2088 show default-collect
2089 Define a list of expressions to be collected at each tracepoint.
2090 This is a useful way to ensure essential items are not overlooked,
2091 such as registers or a critical global variable.
2093 set disconnected-tracing
2094 show disconnected-tracing
2095 If set to 1, the target is instructed to continue tracing if it
2096 loses its connection to GDB. If 0, the target is to stop tracing
2099 set circular-trace-buffer
2100 show circular-trace-buffer
2101 If set to on, the target is instructed to use a circular trace buffer
2102 and discard the oldest trace frames instead of stopping the trace due
2103 to a full trace buffer. If set to off, the trace stops when the buffer
2104 fills up. Some targets may not support this.
2106 set script-extension off|soft|strict
2107 show script-extension
2108 If set to "off", the debugger does not perform any script language
2109 recognition, and all sourced files are assumed to be GDB scripts.
2110 If set to "soft" (the default), files are sourced according to
2111 filename extension, falling back to GDB scripts if the first
2113 If set to "strict", files are sourced according to filename extension.
2115 set ada trust-PAD-over-XVS on|off
2116 show ada trust-PAD-over-XVS
2117 If off, activate a workaround against a bug in the debugging information
2118 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2119 the GCC sources for more information about the GNAT encoding and
2120 PAD types in particular). It is always safe to set this option to
2121 off, but this introduces a slight performance penalty. The default
2124 * Python API Improvements
2126 ** GDB provides the new class gdb.LazyString. This is useful in
2127 some pretty-printing cases. The new method gdb.Value.lazy_string
2128 provides a simple way to create objects of this type.
2130 ** The fields returned by gdb.Type.fields now have an
2131 `is_base_class' attribute.
2133 ** The new method gdb.Type.range returns the range of an array type.
2135 ** The new method gdb.parse_and_eval can be used to parse and
2136 evaluate an expression.
2138 * New remote packets
2141 Define a trace state variable.
2144 Get the current value of a trace state variable.
2147 Set desired tracing behavior upon disconnection.
2150 Set the trace buffer to be linear or circular.
2153 Get data about the tracepoints currently in use.
2157 Process record now works correctly with hardware watchpoints.
2159 Multiple bug fixes have been made to the mips-irix port, making it
2160 much more reliable. In particular:
2161 - Debugging threaded applications is now possible again. Previously,
2162 GDB would hang while starting the program, or while waiting for
2163 the program to stop at a breakpoint.
2164 - Attaching to a running process no longer hangs.
2165 - An error occurring while loading a core file has been fixed.
2166 - Changing the value of the PC register now works again. This fixes
2167 problems observed when using the "jump" command, or when calling
2168 a function from GDB, or even when assigning a new value to $pc.
2169 - With the "finish" and "return" commands, the return value for functions
2170 returning a small array is now correctly printed.
2171 - It is now possible to break on shared library code which gets executed
2172 during a shared library init phase (code executed while executing
2173 their .init section). Previously, the breakpoint would have no effect.
2174 - GDB is now able to backtrace through the signal handler for
2175 non-threaded programs.
2177 PIE (Position Independent Executable) programs debugging is now supported.
2178 This includes debugging execution of PIC (Position Independent Code) shared
2179 libraries although for that, it should be possible to run such libraries as an
2182 *** Changes in GDB 7.0
2184 * GDB now has an interface for JIT compilation. Applications that
2185 dynamically generate code can create symbol files in memory and register
2186 them with GDB. For users, the feature should work transparently, and
2187 for JIT developers, the interface is documented in the GDB manual in the
2188 "JIT Compilation Interface" chapter.
2190 * Tracepoints may now be conditional. The syntax is as for
2191 breakpoints; either an "if" clause appended to the "trace" command,
2192 or the "condition" command is available. GDB sends the condition to
2193 the target for evaluation using the same bytecode format as is used
2194 for tracepoint actions.
2196 * The disassemble command now supports: an optional /r modifier, print the
2197 raw instructions in hex as well as in symbolic form, and an optional /m
2198 modifier to print mixed source+assembly.
2200 * Process record and replay
2202 In a architecture environment that supports ``process record and
2203 replay'', ``process record and replay'' target can record a log of
2204 the process execution, and replay it with both forward and reverse
2207 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2208 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2209 set execution-direction {forward|reverse}, for targets that support
2212 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2213 feature is available with a native GDB running on kernel version
2216 * GDB now has support for multi-byte and wide character sets on the
2217 target. Strings whose character type is wchar_t, char16_t, or
2218 char32_t are now correctly printed. GDB supports wide- and unicode-
2219 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2220 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2221 `printf'. This feature requires iconv to work properly; if your
2222 system does not have a working iconv, GDB can use GNU libiconv. See
2223 the installation instructions for more information.
2225 * GDB now supports automatic retrieval of shared library files from
2226 remote targets. To use this feature, specify a system root that begins
2227 with the `remote:' prefix, either via the `set sysroot' command or via
2228 the `--with-sysroot' configure-time option.
2230 * "info sharedlibrary" now takes an optional regex of libraries to show,
2231 and it now reports if a shared library has no debugging information.
2233 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2234 now complete on file names.
2236 * When completing in expressions, gdb will attempt to limit
2237 completions to allowable structure or union fields, where appropriate.
2238 For instance, consider:
2240 # struct example { int f1; double f2; };
2241 # struct example variable;
2244 If the user types TAB at the end of this command line, the available
2245 completions will be "f1" and "f2".
2247 * Inlined functions are now supported. They show up in backtraces, and
2248 the "step", "next", and "finish" commands handle them automatically.
2250 * GDB now supports the token-splicing (##) and stringification (#)
2251 operators when expanding macros. It also supports variable-arity
2254 * GDB now supports inspecting extra signal information, exported by
2255 the new $_siginfo convenience variable. The feature is currently
2256 implemented on linux ARM, i386 and amd64.
2258 * GDB can now display the VFP floating point registers and NEON vector
2259 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2260 can provide these registers (requires Linux 2.6.30 or later). Remote
2261 and simulator targets may also provide them.
2263 * New remote packets
2266 Search memory for a sequence of bytes.
2269 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2270 operation over reliable transport links. Use of this packet is
2271 controlled by the `set remote noack-packet' command.
2274 Kill the process with the specified process ID. Use this in preference
2275 to `k' when multiprocess protocol extensions are supported.
2278 Obtains additional operating system information
2282 Read or write additional signal information.
2284 * Removed remote protocol undocumented extension
2286 An undocumented extension to the remote protocol's `S' stop reply
2287 packet that permited the stub to pass a process id was removed.
2288 Remote servers should use the `T' stop reply packet instead.
2290 * GDB now supports multiple function calling conventions according to the
2291 DWARF-2 DW_AT_calling_convention function attribute.
2293 * The SH target utilizes the aforementioned change to distinguish between gcc
2294 and Renesas calling convention. It also adds the new CLI commands
2295 `set/show sh calling-convention'.
2297 * GDB can now read compressed debug sections, as produced by GNU gold
2298 with the --compress-debug-sections=zlib flag.
2300 * 64-bit core files are now supported on AIX.
2302 * Thread switching is now supported on Tru64.
2304 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2305 which will be allocated using malloc later in program execution.
2307 * The qXfer:libraries:read remote procotol packet now allows passing a
2308 list of section offsets.
2310 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2311 conditions handling signals delivered during attach or thread creation
2312 have also been fixed.
2314 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2315 From the user's standpoint, all unqualified instances of True and False
2316 are treated as the standard definitions, regardless of context.
2318 * GDB now parses C++ symbol and type names more flexibly. For
2321 template<typename T> class C { };
2324 GDB will now correctly handle all of:
2326 ptype C<char const *>
2327 ptype C<char const*>
2328 ptype C<const char *>
2329 ptype C<const char*>
2331 * New features in the GDB remote stub, gdbserver
2333 - The "--wrapper" command-line argument tells gdbserver to use a
2334 wrapper program to launch programs for debugging.
2336 - On PowerPC and S/390 targets, it is now possible to use a single
2337 gdbserver executable to debug both 32-bit and 64-bit programs.
2338 (This requires gdbserver itself to be built as a 64-bit executable.)
2340 - gdbserver uses the new noack protocol mode for TCP connections to
2341 reduce communications latency, if also supported and enabled in GDB.
2343 - Support for the sparc64-linux-gnu target is now included in
2346 - The amd64-linux build of gdbserver now supports debugging both
2347 32-bit and 64-bit programs.
2349 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2350 now support hardware watchpoints, and will use them automatically
2355 GDB now has support for scripting using Python. Whether this is
2356 available is determined at configure time.
2358 New GDB commands can now be written in Python.
2360 * Ada tasking support
2362 Ada tasks can now be inspected in GDB. The following commands have
2366 Print the list of Ada tasks.
2368 Print detailed information about task number N.
2370 Print the task number of the current task.
2372 Switch the context of debugging to task number N.
2374 * Support for user-defined prefixed commands. The "define" command can
2375 add new commands to existing prefixes, e.g. "target".
2377 * Multi-inferior, multi-process debugging.
2379 GDB now has generalized support for multi-inferior debugging. See
2380 "Debugging Multiple Inferiors" in the manual for more information.
2381 Although availability still depends on target support, the command
2382 set is more uniform now. The GNU/Linux specific multi-forks support
2383 has been migrated to this new framework. This implied some user
2384 visible changes; see "New commands" and also "Removed commands"
2387 * Target descriptions can now describe the target OS ABI. See the
2388 "Target Description Format" section in the user manual for more
2391 * Target descriptions can now describe "compatible" architectures
2392 to indicate that the target can execute applications for a different
2393 architecture in addition to those for the main target architecture.
2394 See the "Target Description Format" section in the user manual for
2397 * Multi-architecture debugging.
2399 GDB now includes general supports for debugging applications on
2400 hybrid systems that use more than one single processor architecture
2401 at the same time. Each such hybrid architecture still requires
2402 specific support to be added. The only hybrid architecture supported
2403 in this version of GDB is the Cell Broadband Engine.
2405 * GDB now supports integrated debugging of Cell/B.E. applications that
2406 use both the PPU and SPU architectures. To enable support for hybrid
2407 Cell/B.E. debugging, you need to configure GDB to support both the
2408 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2409 --enable-targets configure option.
2411 * Non-stop mode debugging.
2413 For some targets, GDB now supports an optional mode of operation in
2414 which you can examine stopped threads while other threads continue
2415 to execute freely. This is referred to as non-stop mode, with the
2416 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2417 section in the user manual for more information.
2419 To be able to support remote non-stop debugging, a remote stub needs
2420 to implement the non-stop mode remote protocol extensions, as
2421 described in the "Remote Non-Stop" section of the user manual. The
2422 GDB remote stub, gdbserver, has been adjusted to support these
2423 extensions on linux targets.
2425 * New commands (for set/show, see "New options" below)
2427 catch syscall [NAME(S) | NUMBER(S)]
2428 Catch system calls. Arguments, which should be names of system
2429 calls or their numbers, mean catch only those syscalls. Without
2430 arguments, every syscall will be caught. When the inferior issues
2431 any of the specified syscalls, GDB will stop and announce the system
2432 call, both when it is called and when its call returns. This
2433 feature is currently available with a native GDB running on the
2434 Linux Kernel, under the following architectures: x86, x86_64,
2435 PowerPC and PowerPC64.
2437 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2439 Search memory for a sequence of bytes.
2441 maint set python print-stack
2442 maint show python print-stack
2443 Show a stack trace when an error is encountered in a Python script.
2446 Invoke CODE by passing it to the Python interpreter.
2451 These allow macros to be defined, undefined, and listed
2455 Show operating system information about processes.
2458 List the inferiors currently under GDB's control.
2461 Switch focus to inferior number NUM.
2464 Detach from inferior number NUM.
2467 Kill inferior number NUM.
2471 set spu stop-on-load
2472 show spu stop-on-load
2473 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2475 set spu auto-flush-cache
2476 show spu auto-flush-cache
2477 Control whether to automatically flush the software-managed cache
2478 during Cell/B.E. debugging.
2480 set sh calling-convention
2481 show sh calling-convention
2482 Control the calling convention used when calling SH target functions.
2485 show debug timestamp
2486 Control display of timestamps with GDB debugging output.
2488 set disassemble-next-line
2489 show disassemble-next-line
2490 Control display of disassembled source lines or instructions when
2493 set remote noack-packet
2494 show remote noack-packet
2495 Set/show the use of remote protocol QStartNoAckMode packet. See above
2496 under "New remote packets."
2498 set remote query-attached-packet
2499 show remote query-attached-packet
2500 Control use of remote protocol `qAttached' (query-attached) packet.
2502 set remote read-siginfo-object
2503 show remote read-siginfo-object
2504 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2507 set remote write-siginfo-object
2508 show remote write-siginfo-object
2509 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2512 set remote reverse-continue
2513 show remote reverse-continue
2514 Control use of remote protocol 'bc' (reverse-continue) packet.
2516 set remote reverse-step
2517 show remote reverse-step
2518 Control use of remote protocol 'bs' (reverse-step) packet.
2520 set displaced-stepping
2521 show displaced-stepping
2522 Control displaced stepping mode. Displaced stepping is a way to
2523 single-step over breakpoints without removing them from the debuggee.
2524 Also known as "out-of-line single-stepping".
2527 show debug displaced
2528 Control display of debugging info for displaced stepping.
2530 maint set internal-error
2531 maint show internal-error
2532 Control what GDB does when an internal error is detected.
2534 maint set internal-warning
2535 maint show internal-warning
2536 Control what GDB does when an internal warning is detected.
2541 Use a wrapper program to launch programs for debugging.
2543 set multiple-symbols (all|ask|cancel)
2544 show multiple-symbols
2545 The value of this variable can be changed to adjust the debugger behavior
2546 when an expression or a breakpoint location contains an ambiguous symbol
2547 name (an overloaded function name, for instance).
2549 set breakpoint always-inserted
2550 show breakpoint always-inserted
2551 Keep breakpoints always inserted in the target, as opposed to inserting
2552 them when resuming the target, and removing them when the target stops.
2553 This option can improve debugger performance on slow remote targets.
2555 set arm fallback-mode (arm|thumb|auto)
2556 show arm fallback-mode
2557 set arm force-mode (arm|thumb|auto)
2559 These commands control how ARM GDB determines whether instructions
2560 are ARM or Thumb. The default for both settings is auto, which uses
2561 the current CPSR value for instructions without symbols; previous
2562 versions of GDB behaved as if "set arm fallback-mode arm".
2564 set disable-randomization
2565 show disable-randomization
2566 Standalone programs run with the virtual address space randomization enabled
2567 by default on some platforms. This option keeps the addresses stable across
2568 multiple debugging sessions.
2572 Control whether other threads are stopped or not when some thread hits
2577 Requests that asynchronous execution is enabled in the target, if available.
2578 In this case, it's possible to resume target in the background, and interact
2579 with GDB while the target is running. "show target-async" displays the
2580 current state of asynchronous execution of the target.
2582 set target-wide-charset
2583 show target-wide-charset
2584 The target-wide-charset is the name of the character set that GDB
2585 uses when printing characters whose type is wchar_t.
2587 set tcp auto-retry (on|off)
2589 set tcp connect-timeout
2590 show tcp connect-timeout
2591 These commands allow GDB to retry failed TCP connections to a remote stub
2592 with a specified timeout period; this is useful if the stub is launched
2593 in parallel with GDB but may not be ready to accept connections immediately.
2595 set libthread-db-search-path
2596 show libthread-db-search-path
2597 Control list of directories which GDB will search for appropriate
2600 set schedule-multiple (on|off)
2601 show schedule-multiple
2602 Allow GDB to resume all threads of all processes or only threads of
2603 the current process.
2607 Use more aggressive caching for accesses to the stack. This improves
2608 performance of remote debugging (particularly backtraces) without
2609 affecting correctness.
2611 set interactive-mode (on|off|auto)
2612 show interactive-mode
2613 Control whether GDB runs in interactive mode (on) or not (off).
2614 When in interactive mode, GDB waits for the user to answer all
2615 queries. Otherwise, GDB does not wait and assumes the default
2616 answer. When set to auto (the default), GDB determines which
2617 mode to use based on the stdin settings.
2622 For program forks, this is replaced by the new more generic `info
2623 inferiors' command. To list checkpoints, you can still use the
2624 `info checkpoints' command, which was an alias for the `info forks'
2628 Replaced by the new `inferior' command. To switch between
2629 checkpoints, you can still use the `restart' command, which was an
2630 alias for the `fork' command.
2633 This is removed, since some targets don't have a notion of
2634 processes. To switch between processes, you can still use the
2635 `inferior' command using GDB's own inferior number.
2638 For program forks, this is replaced by the new more generic `kill
2639 inferior' command. To delete a checkpoint, you can still use the
2640 `delete checkpoint' command, which was an alias for the `delete
2644 For program forks, this is replaced by the new more generic `detach
2645 inferior' command. To detach a checkpoint, you can still use the
2646 `detach checkpoint' command, which was an alias for the `detach
2649 * New native configurations
2651 x86/x86_64 Darwin i[34567]86-*-darwin*
2653 x86_64 MinGW x86_64-*-mingw*
2657 Lattice Mico32 lm32-*
2658 x86 DICOS i[34567]86-*-dicos*
2659 x86_64 DICOS x86_64-*-dicos*
2662 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2663 (mingw32ce) debugging.
2669 These commands were actually not implemented on any target.
2671 *** Changes in GDB 6.8
2673 * New native configurations
2675 NetBSD/hppa hppa*-*netbsd*
2676 Xtensa GNU/Linux xtensa*-*-linux*
2680 NetBSD/hppa hppa*-*-netbsd*
2681 Xtensa GNU/Lunux xtensa*-*-linux*
2683 * Change in command line behavior -- corefiles vs. process ids.
2685 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2686 attaching to process NUMBER fails, GDB no longer attempts to open a
2687 core file named NUMBER. Attaching to a program using the -c option
2688 is no longer supported. Instead, use the '-p' or '--pid' options.
2690 * GDB can now be built as a native debugger for debugging Windows x86
2691 (mingw32) Portable Executable (PE) programs.
2693 * Pending breakpoints no longer change their number when their address
2696 * GDB now supports breakpoints with multiple locations,
2697 including breakpoints on C++ constructors, inside C++ templates,
2698 and in inlined functions.
2700 * GDB's ability to debug optimized code has been improved. GDB more
2701 accurately identifies function bodies and lexical blocks that occupy
2702 more than one contiguous range of addresses.
2704 * Target descriptions can now describe registers for PowerPC.
2706 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2707 registers on PowerPC targets.
2709 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2710 targets even when the libthread_db library is not available.
2712 * The GDB remote stub, gdbserver, now supports the new file transfer
2713 commands (remote put, remote get, and remote delete).
2715 * The GDB remote stub, gdbserver, now supports run and attach in
2716 extended-remote mode.
2718 * hppa*64*-*-hpux11* target broken
2719 The debugger is unable to start a program and fails with the following
2720 error: "Error trying to get information about dynamic linker".
2721 The gdb-6.7 release is also affected.
2723 * GDB now supports the --enable-targets= configure option to allow
2724 building a single GDB executable that supports multiple remote
2725 target architectures.
2727 * GDB now supports debugging C and C++ programs which use the
2728 Decimal Floating Point extension. In addition, the PowerPC target
2729 now has a set of pseudo-registers to inspect decimal float values
2730 stored in two consecutive float registers.
2732 * The -break-insert MI command can optionally create pending
2735 * Improved support for debugging Ada
2736 Many improvements to the Ada language support have been made. These
2738 - Better support for Ada2005 interface types
2739 - Improved handling of arrays and slices in general
2740 - Better support for Taft-amendment types
2741 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2743 - Improved command completion in Ada
2746 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2751 set print frame-arguments (all|scalars|none)
2752 show print frame-arguments
2753 The value of this variable can be changed to control which argument
2754 values should be printed by the debugger when displaying a frame.
2759 Transfer files to and from a remote target, and delete remote files.
2766 Transfer files to and from a remote target, and delete remote files.
2768 * New remote packets
2775 Open, close, read, write, and delete files on the remote system.
2778 Attach to an existing process on the remote system, in extended-remote
2782 Run a new process on the remote system, in extended-remote mode.
2784 *** Changes in GDB 6.7
2786 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2787 bfd, libiberty and opcodes, as revealed by static analysis donated by
2788 Coverity, Inc. (http://scan.coverity.com).
2790 * When looking up multiply-defined global symbols, GDB will now prefer the
2791 symbol definition in the current shared library if it was built using the
2792 -Bsymbolic linker option.
2794 * When the Text User Interface (TUI) is not configured, GDB will now
2795 recognize the -tui command-line option and print a message that the TUI
2798 * The GDB remote stub, gdbserver, now has lower overhead for high
2799 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2801 * GDB for MIPS targets now autodetects whether a remote target provides
2802 32-bit or 64-bit register values.
2804 * Support for C++ member pointers has been improved.
2806 * GDB now understands XML target descriptions, which specify the
2807 target's overall architecture. GDB can read a description from
2808 a local file or over the remote serial protocol.
2810 * Vectors of single-byte data use a new integer type which is not
2811 automatically displayed as character or string data.
2813 * The /s format now works with the print command. It displays
2814 arrays of single-byte integers and pointers to single-byte integers
2817 * Target descriptions can now describe target-specific registers,
2818 for architectures which have implemented the support (currently
2819 only ARM, M68K, and MIPS).
2821 * GDB and the GDB remote stub, gdbserver, now support the XScale
2824 * The GDB remote stub, gdbserver, has been updated to support
2825 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2826 has been rewritten to use the standard GDB remote protocol.
2828 * GDB can now step into C++ functions which are called through thunks.
2830 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2832 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2833 layout. It also supports a TextSeg= and DataSeg= response when only
2834 segment base addresses (rather than offsets) are available.
2836 * The /i format now outputs any trailing branch delay slot instructions
2837 immediately following the last instruction within the count specified.
2839 * The GDB remote protocol "T" stop reply packet now supports a
2840 "library" response. Combined with the new "qXfer:libraries:read"
2841 packet, this response allows GDB to debug shared libraries on targets
2842 where the operating system manages the list of loaded libraries (e.g.
2843 Windows and SymbianOS).
2845 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2846 (DLLs) on Windows and Windows CE targets.
2848 * GDB now supports a faster verification that a .debug file matches its binary
2849 according to its build-id signature, if the signature is present.
2855 Enable or disable hardware flow control (RTS/CTS) on the serial port
2856 when debugging using remote targets.
2858 set mem inaccessible-by-default
2859 show mem inaccessible-by-default
2860 If the target supplies a memory map, for instance via the remote
2861 protocol's "qXfer:memory-map:read" packet, setting this variable
2862 prevents GDB from accessing memory outside the memory map. This
2863 is useful for targets with memory mapped registers or which react
2864 badly to accesses of unmapped address space.
2866 set breakpoint auto-hw
2867 show breakpoint auto-hw
2868 If the target supplies a memory map, for instance via the remote
2869 protocol's "qXfer:memory-map:read" packet, setting this variable
2870 lets GDB use hardware breakpoints automatically for memory regions
2871 where it can not use software breakpoints. This covers both the
2872 "break" command and internal breakpoints used for other commands
2873 including "next" and "finish".
2876 catch exception unhandled
2877 Stop the program execution when Ada exceptions are raised.
2880 Stop the program execution when an Ada assertion failed.
2884 Set an alternate system root for target files. This is a more
2885 general version of "set solib-absolute-prefix", which is now
2886 an alias to "set sysroot".
2889 Provide extended SPU facility status information. This set of
2890 commands is available only when debugging the Cell/B.E. SPU
2893 * New native configurations
2895 OpenBSD/sh sh*-*openbsd*
2898 unset tdesc filename
2900 Use the specified local file as an XML target description, and do
2901 not query the target for its built-in description.
2905 OpenBSD/sh sh*-*-openbsd*
2906 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2907 Toshiba Media Processor mep-elf
2909 * New remote packets
2912 Ignore the specified signals; pass them directly to the debugged program
2913 without stopping other threads or reporting them to GDB.
2915 qXfer:features:read:
2916 Read an XML target description from the target, which describes its
2921 Read or write contents of an spufs file on the target system. These
2922 packets are available only on the Cell/B.E. SPU architecture.
2924 qXfer:libraries:read:
2925 Report the loaded shared libraries. Combined with new "T" packet
2926 response, this packet allows GDB to debug shared libraries on
2927 targets where the operating system manages the list of loaded
2928 libraries (e.g. Windows and SymbianOS).
2932 Support for these obsolete configurations has been removed.
2940 i[34567]86-*-lynxos*
2941 i[34567]86-*-netware*
2942 i[34567]86-*-sco3.2v5*
2943 i[34567]86-*-sco3.2v4*
2945 i[34567]86-*-sysv4.2*
2948 i[34567]86-*-unixware2*
2949 i[34567]86-*-unixware*
2958 * Other removed features
2965 Various m68k-only ROM monitors.
2972 Various Renesas ROM monitors and debugging interfaces for SH and
2977 Support for a Macraigor serial interface to on-chip debugging.
2978 GDB does not directly support the newer parallel or USB
2983 A debug information format. The predecessor to DWARF 2 and
2984 DWARF 3, which are still supported.
2986 Support for the HP aCC compiler on HP-UX/PA-RISC
2988 SOM-encapsulated symbolic debugging information, automatic
2989 invocation of pxdb, and the aCC custom C++ ABI. This does not
2990 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2991 with aCC can still be debugged on an assembly level.
2993 MIPS ".pdr" sections
2995 A MIPS-specific format used to describe stack frame layout
2996 in debugging information.
3000 GDB could work with an older version of Guile to debug
3001 the interpreter and Scheme programs running in it.
3003 set mips stack-arg-size
3004 set mips saved-gpreg-size
3006 Use "set mips abi" to control parameter passing for MIPS.
3008 *** Changes in GDB 6.6
3013 Cell Broadband Engine SPU spu-elf
3015 * GDB can now be configured as a cross-debugger targeting native Windows
3016 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3017 running on a Windows system over TCP/IP to debug Windows programs.
3019 * The GDB remote stub, gdbserver, has been updated to support Windows and
3020 Cygwin debugging. Both single-threaded and multi-threaded programs are
3023 * The "set trust-readonly-sections" command works again. This command was
3024 broken in GDB 6.3, 6.4, and 6.5.
3026 * The "load" command now supports writing to flash memory, if the remote
3027 stub provides the required support.
3029 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3030 longer requires symbolic debug information (e.g. DWARF-2).
3035 unset substitute-path
3036 show substitute-path
3037 Manage a list of substitution rules that GDB uses to rewrite the name
3038 of the directories where the sources are located. This can be useful
3039 for instance when the sources were moved to a different location
3040 between compilation and debugging.
3044 Print each CLI command as it is executed. Each command is prefixed with
3045 a number of `+' symbols representing the nesting depth.
3046 The source command now has a `-v' option to enable the same feature.
3050 The ARM Demon monitor support (RDP protocol, "target rdp").
3052 Kernel Object Display, an embedded debugging feature which only worked with
3053 an obsolete version of Cisco IOS.
3055 The 'set download-write-size' and 'show download-write-size' commands.
3057 * New remote packets
3060 Tell a stub about GDB client features, and request remote target features.
3061 The first feature implemented is PacketSize, which allows the target to
3062 specify the size of packets it can handle - to minimize the number of
3063 packets required and improve performance when connected to a remote
3067 Fetch an OS auxilliary vector from the remote stub. This packet is a
3068 more efficient replacement for qPart:auxv:read.
3070 qXfer:memory-map:read:
3071 Fetch a memory map from the remote stub, including information about
3072 RAM, ROM, and flash memory devices.
3077 Erase and program a flash memory device.
3079 * Removed remote packets
3082 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3083 used it, and only gdbserver implemented it.
3085 *** Changes in GDB 6.5
3089 Renesas M32C/M16C m32c-elf
3091 Morpho Technologies ms1 ms1-elf
3095 init-if-undefined Initialize a convenience variable, but
3096 only if it doesn't already have a value.
3098 The following commands are presently only implemented for native GNU/Linux:
3100 checkpoint Save a snapshot of the program state.
3102 restart <n> Return the program state to a
3103 previously saved state.
3105 info checkpoints List currently saved checkpoints.
3107 delete-checkpoint <n> Delete a previously saved checkpoint.
3109 set|show detach-on-fork Tell gdb whether to detach from a newly
3110 forked process, or to keep debugging it.
3112 info forks List forks of the user program that
3113 are available to be debugged.
3115 fork <n> Switch to debugging one of several
3116 forks of the user program that are
3117 available to be debugged.
3119 delete-fork <n> Delete a fork from the list of forks
3120 that are available to be debugged (and
3121 kill the forked process).
3123 detach-fork <n> Delete a fork from the list of forks
3124 that are available to be debugged (and
3125 allow the process to continue).
3129 Morpho Technologies ms2 ms1-elf
3131 * Improved Windows host support
3133 GDB now builds as a cross debugger hosted on i686-mingw32, including
3134 native console support, and remote communications using either
3135 network sockets or serial ports.
3137 * Improved Modula-2 language support
3139 GDB can now print most types in the Modula-2 syntax. This includes:
3140 basic types, set types, record types, enumerated types, range types,
3141 pointer types and ARRAY types. Procedure var parameters are correctly
3142 printed and hexadecimal addresses and character constants are also
3143 written in the Modula-2 syntax. Best results can be obtained by using
3144 GNU Modula-2 together with the -gdwarf-2 command line option.
3148 The ARM rdi-share module.
3150 The Netware NLM debug server.
3152 *** Changes in GDB 6.4
3154 * New native configurations
3156 OpenBSD/arm arm*-*-openbsd*
3157 OpenBSD/mips64 mips64-*-openbsd*
3161 Morpho Technologies ms1 ms1-elf
3163 * New command line options
3165 --batch-silent As for --batch, but totally silent.
3166 --return-child-result The debugger will exist with the same value
3167 the child (debugged) program exited with.
3168 --eval-command COMMAND, -ex COMMAND
3169 Execute a single GDB CLI command. This may be
3170 specified multiple times and in conjunction
3171 with the --command (-x) option.
3173 * Deprecated commands removed
3175 The following commands, that were deprecated in 2000, have been
3179 set|show arm disassembly-flavor set|show arm disassembler
3180 othernames set arm disassembler
3181 set|show remotedebug set|show debug remote
3182 set|show archdebug set|show debug arch
3183 set|show eventdebug set|show debug event
3186 * New BSD user-level threads support
3188 It is now possible to debug programs using the user-level threads
3189 library on OpenBSD and FreeBSD. Currently supported (target)
3192 FreeBSD/amd64 x86_64-*-freebsd*
3193 FreeBSD/i386 i386-*-freebsd*
3194 OpenBSD/i386 i386-*-openbsd*
3196 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3197 are not yet supported.
3199 * New support for Matsushita MN10300 w/sim added
3200 (Work in progress). mn10300-elf.
3202 * REMOVED configurations and files
3204 VxWorks and the XDR protocol *-*-vxworks
3205 Motorola MCORE mcore-*-*
3206 National Semiconductor NS32000 ns32k-*-*
3208 * New "set print array-indexes" command
3210 After turning this setting "on", GDB prints the index of each element
3211 when displaying arrays. The default is "off" to preserve the previous
3214 * VAX floating point support
3216 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3218 * User-defined command support
3220 In addition to using $arg0..$arg9 for argument passing, it is now possible
3221 to use $argc to determine now many arguments have been passed. See the
3222 section on user-defined commands in the user manual for more information.
3224 *** Changes in GDB 6.3:
3226 * New command line option
3228 GDB now accepts -l followed by a number to set the timeout for remote
3231 * GDB works with GCC -feliminate-dwarf2-dups
3233 GDB now supports a more compact representation of DWARF-2 debug
3234 information using DW_FORM_ref_addr references. These are produced
3235 by GCC with the option -feliminate-dwarf2-dups and also by some
3236 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3237 to use -feliminate-dwarf2-dups.
3239 * Internationalization
3241 When supported by the host system, GDB will be built with
3242 internationalization (libintl). The task of marking up the sources is
3243 continued, we're looking forward to our first translation.
3247 Initial support for debugging programs compiled with the GNAT
3248 implementation of the Ada programming language has been integrated
3249 into GDB. In this release, support is limited to expression evaluation.
3251 * New native configurations
3253 GNU/Linux/m32r m32r-*-linux-gnu
3257 GDB's remote protocol now includes support for the 'p' packet. This
3258 packet is used to fetch individual registers from a remote inferior.
3260 * END-OF-LIFE registers[] compatibility module
3262 GDB's internal register infrastructure has been completely rewritten.
3263 The new infrastructure making possible the implementation of key new
3264 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3267 GDB 6.3 will be the last release to include the the registers[]
3268 compatibility module that allowed out-of-date configurations to
3269 continue to work. This change directly impacts the following
3279 powerpc bdm protocol
3281 Unless there is activity to revive these configurations, they will be
3282 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3284 * OBSOLETE configurations and files
3286 Configurations that have been declared obsolete in this release have
3287 been commented out. Unless there is activity to revive these
3288 configurations, the next release of GDB will have their sources
3289 permanently REMOVED.
3298 *** Changes in GDB 6.2.1:
3300 * MIPS `break main; run' gave an heuristic-fence-post warning
3302 When attempting to run even a simple program, a warning about
3303 heuristic-fence-post being hit would be reported. This problem has
3306 * MIPS IRIX 'long double' crashed GDB
3308 When examining a long double variable, GDB would get a segmentation
3309 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3310 IRIX long double values).
3314 A bug in the VAX stack code was causing problems with the "next"
3315 command. This problem has been fixed.
3317 *** Changes in GDB 6.2:
3319 * Fix for ``many threads''
3321 On GNU/Linux systems that use the NPTL threads library, a program
3322 rapidly creating and deleting threads would confuse GDB leading to the
3325 ptrace: No such process.
3326 thread_db_get_info: cannot get thread info: generic error
3328 This problem has been fixed.
3330 * "-async" and "-noasync" options removed.
3332 Support for the broken "-noasync" option has been removed (it caused
3335 * New ``start'' command.
3337 This command runs the program until the begining of the main procedure.
3339 * New BSD Kernel Data Access Library (libkvm) interface
3341 Using ``target kvm'' it is now possible to debug kernel core dumps and
3342 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3343 platforms. Currently supported (native-only) configurations are:
3345 FreeBSD/amd64 x86_64-*-freebsd*
3346 FreeBSD/i386 i?86-*-freebsd*
3347 NetBSD/i386 i?86-*-netbsd*
3348 NetBSD/m68k m68*-*-netbsd*
3349 NetBSD/sparc sparc-*-netbsd*
3350 OpenBSD/amd64 x86_64-*-openbsd*
3351 OpenBSD/i386 i?86-*-openbsd*
3352 OpenBSD/m68k m68*-openbsd*
3353 OpenBSD/sparc sparc-*-openbsd*
3355 * Signal trampoline code overhauled
3357 Many generic problems with GDB's signal handling code have been fixed.
3358 These include: backtraces through non-contiguous stacks; recognition
3359 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3360 call; backtrace through a signal trampoline; step into and out of
3361 signal handlers; and single-stepping in the signal trampoline.
3363 Please note that kernel bugs are a limiting factor here. These
3364 features have been shown to work on an s390 GNU/Linux system that
3365 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3367 * Cygwin support for DWARF 2 added.
3369 * New native configurations
3371 GNU/Linux/hppa hppa*-*-linux*
3372 OpenBSD/hppa hppa*-*-openbsd*
3373 OpenBSD/m68k m68*-*-openbsd*
3374 OpenBSD/m88k m88*-*-openbsd*
3375 OpenBSD/powerpc powerpc-*-openbsd*
3376 NetBSD/vax vax-*-netbsd*
3377 OpenBSD/vax vax-*-openbsd*
3379 * END-OF-LIFE frame compatibility module
3381 GDB's internal frame infrastructure has been completely rewritten.
3382 The new infrastructure making it possible to support key new features
3383 including DWARF 2 Call Frame Information. To aid in the task of
3384 migrating old configurations to this new infrastructure, a
3385 compatibility module, that allowed old configurations to continue to
3386 work, was also included.
3388 GDB 6.2 will be the last release to include this frame compatibility
3389 module. This change directly impacts the following configurations:
3399 Unless there is activity to revive these configurations, they will be
3400 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3402 * REMOVED configurations and files
3404 Sun 3, running SunOS 3 m68*-*-sunos3*
3405 Sun 3, running SunOS 4 m68*-*-sunos4*
3406 Sun 2, running SunOS 3 m68000-*-sunos3*
3407 Sun 2, running SunOS 4 m68000-*-sunos4*
3408 Motorola 680x0 running LynxOS m68*-*-lynxos*
3409 AT&T 3b1/Unix pc m68*-att-*
3410 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3411 decstation mips-dec-* mips-little-*
3412 riscos mips-*-riscos* mips-*-sysv*
3413 sonymips mips-sony-*
3414 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3416 *** Changes in GDB 6.1.1:
3418 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3420 The TUI (Text-mode User Interface) is now built as part of a default
3421 GDB configuration. It is enabled by either selecting the TUI with the
3422 command line option "-i=tui" or by running the separate "gdbtui"
3423 program. For more information on the TUI, see the manual "Debugging
3426 * Pending breakpoint support (also included in GDB 6.1)
3428 Support has been added to allow you to specify breakpoints in shared
3429 libraries that have not yet been loaded. If a breakpoint location
3430 cannot be found, and the "breakpoint pending" option is set to auto,
3431 GDB queries you if you wish to make the breakpoint pending on a future
3432 shared-library load. If and when GDB resolves the breakpoint symbol,
3433 the pending breakpoint is removed as one or more regular breakpoints
3436 Pending breakpoints are very useful for GCJ Java debugging.
3438 * Fixed ISO-C build problems
3440 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3441 non ISO-C code that stopped them being built using a more strict ISO-C
3442 compiler (e.g., IBM's C compiler).
3444 * Fixed build problem on IRIX 5
3446 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3447 wasn't able to compile compile on an IRIX 5 system.
3449 * Added execute permission to gdb/gdbserver/configure
3451 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3452 permission. This bug would cause configure to fail on a number of
3453 systems (Solaris, IRIX). Ref: server/519.
3455 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3457 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3458 has been updated to use constant array sizes.
3460 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3462 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3463 its generated DWARF Call Frame Info. This encoding was causing GDB to
3464 panic, that panic has been fixed. Ref: gdb/1628.
3466 * Fixed a problem when examining parameters in shared library code.
3468 When examining parameters in optimized shared library code generated
3469 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3470 not available''. GDB now correctly displays the variable's value.
3472 *** Changes in GDB 6.1:
3474 * Removed --with-mmalloc
3476 Support for the mmalloc memory manager has been removed, as it
3477 conflicted with the internal gdb byte cache.
3479 * Changes in AMD64 configurations
3481 The AMD64 target now includes the %cs and %ss registers. As a result
3482 the AMD64 remote protocol has changed; this affects the floating-point
3483 and SSE registers. If you rely on those registers for your debugging,
3484 you should upgrade gdbserver on the remote side.
3486 * Revised SPARC target
3488 The SPARC target has been completely revised, incorporating the
3489 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3490 support for LynxOS and SunOS 4 has been dropped. Calling functions
3491 from within GDB on operating systems with a non-executable stack
3492 (Solaris, OpenBSD) now works.
3496 GDB has a new C++ demangler which does a better job on the mangled
3497 names generated by current versions of g++. It also runs faster, so
3498 with this and other changes gdb should now start faster on large C++
3501 * DWARF 2 Location Expressions
3503 GDB support for location expressions has been extended to support function
3504 arguments and frame bases. Older versions of GDB could crash when they
3507 * C++ nested types and namespaces
3509 GDB's support for nested types and namespaces in C++ has been
3510 improved, especially if you use the DWARF 2 debugging format. (This
3511 is the default for recent versions of GCC on most platforms.)
3512 Specifically, if you have a class "Inner" defined within a class or
3513 namespace "Outer", then GDB realizes that the class's name is
3514 "Outer::Inner", not simply "Inner". This should greatly reduce the
3515 frequency of complaints about not finding RTTI symbols. In addition,
3516 if you are stopped at inside of a function defined within a namespace,
3517 GDB modifies its name lookup accordingly.
3519 * New native configurations
3521 NetBSD/amd64 x86_64-*-netbsd*
3522 OpenBSD/amd64 x86_64-*-openbsd*
3523 OpenBSD/alpha alpha*-*-openbsd*
3524 OpenBSD/sparc sparc-*-openbsd*
3525 OpenBSD/sparc64 sparc64-*-openbsd*
3527 * New debugging protocols
3529 M32R with SDI protocol m32r-*-elf*
3531 * "set prompt-escape-char" command deleted.
3533 The command "set prompt-escape-char" has been deleted. This command,
3534 and its very obscure effet on GDB's prompt, was never documented,
3535 tested, nor mentioned in the NEWS file.
3537 * OBSOLETE configurations and files
3539 Configurations that have been declared obsolete in this release have
3540 been commented out. Unless there is activity to revive these
3541 configurations, the next release of GDB will have their sources
3542 permanently REMOVED.
3544 Sun 3, running SunOS 3 m68*-*-sunos3*
3545 Sun 3, running SunOS 4 m68*-*-sunos4*
3546 Sun 2, running SunOS 3 m68000-*-sunos3*
3547 Sun 2, running SunOS 4 m68000-*-sunos4*
3548 Motorola 680x0 running LynxOS m68*-*-lynxos*
3549 AT&T 3b1/Unix pc m68*-att-*
3550 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3551 decstation mips-dec-* mips-little-*
3552 riscos mips-*-riscos* mips-*-sysv*
3553 sonymips mips-sony-*
3554 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3556 * REMOVED configurations and files
3558 SGI Irix-4.x mips-sgi-irix4 or iris4
3559 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3560 Z8000 simulator z8k-zilog-none or z8ksim
3561 Matsushita MN10200 w/simulator mn10200-*-*
3562 H8/500 simulator h8500-hitachi-hms or h8500hms
3563 HP/PA running BSD hppa*-*-bsd*
3564 HP/PA running OSF/1 hppa*-*-osf*
3565 HP/PA Pro target hppa*-*-pro*
3566 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3567 386BSD i[3456]86-*-bsd*
3568 Sequent family i[3456]86-sequent-sysv4*
3569 i[3456]86-sequent-sysv*
3570 i[3456]86-sequent-bsd*
3571 SPARC running LynxOS sparc-*-lynxos*
3572 SPARC running SunOS 4 sparc-*-sunos4*
3573 Tsqware Sparclet sparclet-*-*
3574 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3576 *** Changes in GDB 6.0:
3580 Support for debugging the Objective-C programming language has been
3581 integrated into GDB.
3583 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3585 DWARF 2's Call Frame Information makes available compiler generated
3586 information that more exactly describes the program's run-time stack.
3587 By using this information, GDB is able to provide more robust stack
3590 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3591 have been updated to use a new backtrace mechanism which includes
3592 DWARF 2 CFI support.
3596 GDB's remote protocol has been extended to include support for hosted
3597 file I/O (where the remote target uses GDB's file system). See GDB's
3598 remote protocol documentation for details.
3600 * All targets using the new architecture framework.
3602 All of GDB's targets have been updated to use the new internal
3603 architecture framework. The way is now open for future GDB releases
3604 to include cross-architecture native debugging support (i386 on amd64,
3607 * GNU/Linux's Thread Local Storage (TLS)
3609 GDB now includes support for for the GNU/Linux implementation of
3610 per-thread variables.
3612 * GNU/Linux's Native POSIX Thread Library (NPTL)
3614 GDB's thread code has been updated to work with either the new
3615 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3617 * Separate debug info.
3619 GDB, in conjunction with BINUTILS, now supports a mechanism for
3620 automatically loading debug information from a separate file. Instead
3621 of shipping full debug and non-debug versions of system libraries,
3622 system integrators can now instead ship just the stripped libraries
3623 and optional debug files.
3625 * DWARF 2 Location Expressions
3627 DWARF 2 Location Expressions allow the compiler to more completely
3628 describe the location of variables (even in optimized code) to the
3631 GDB now includes preliminary support for location expressions (support
3632 for DW_OP_piece is still missing).
3636 A number of long standing bugs that caused GDB to die while starting a
3637 Java application have been fixed. GDB's Java support is now
3638 considered "useable".
3640 * GNU/Linux support for fork, vfork, and exec.
3642 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3643 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3646 * GDB supports logging output to a file
3648 There are two new commands, "set logging" and "show logging", which can be
3649 used to capture GDB's output to a file.
3651 * The meaning of "detach" has changed for gdbserver
3653 The "detach" command will now resume the application, as documented. To
3654 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3657 * d10v, m68hc11 `regs' command deprecated
3659 The `info registers' command has been updated so that it displays the
3660 registers using a format identical to the old `regs' command.
3664 A new command, "maint set profile on/off", has been added. This command can
3665 be used to enable or disable profiling while running GDB, to profile a
3666 session or a set of commands. In addition there is a new configure switch,
3667 "--enable-profiling", which will cause GDB to be compiled with profiling
3668 data, for more informative profiling results.
3670 * Default MI syntax changed to "mi2".
3672 The default MI (machine interface) syntax, enabled by the command line
3673 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3674 "mi1", can be enabled by specifying the option "-i=mi1".
3676 Support for the original "mi0" syntax (included in GDB 5.0) has been
3679 Fix for gdb/192: removed extraneous space when displaying frame level.
3680 Fix for gdb/672: update changelist is now output in mi list format.
3681 Fix for gdb/702: a -var-assign that updates the value now shows up
3682 in a subsequent -var-update.
3684 * New native configurations.
3686 FreeBSD/amd64 x86_64-*-freebsd*
3688 * Multi-arched targets.
3690 HP/PA HPUX11 hppa*-*-hpux*
3691 Renesas M32R/D w/simulator m32r-*-elf*
3693 * OBSOLETE configurations and files
3695 Configurations that have been declared obsolete in this release have
3696 been commented out. Unless there is activity to revive these
3697 configurations, the next release of GDB will have their sources
3698 permanently REMOVED.
3700 Z8000 simulator z8k-zilog-none or z8ksim
3701 Matsushita MN10200 w/simulator mn10200-*-*
3702 H8/500 simulator h8500-hitachi-hms or h8500hms
3703 HP/PA running BSD hppa*-*-bsd*
3704 HP/PA running OSF/1 hppa*-*-osf*
3705 HP/PA Pro target hppa*-*-pro*
3706 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3707 Sequent family i[3456]86-sequent-sysv4*
3708 i[3456]86-sequent-sysv*
3709 i[3456]86-sequent-bsd*
3710 Tsqware Sparclet sparclet-*-*
3711 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3713 * REMOVED configurations and files
3716 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3717 IBM AIX PS/2 i[3456]86-*-aix
3718 i386 running Mach 3.0 i[3456]86-*-mach3*
3719 i386 running Mach i[3456]86-*-mach*
3720 i386 running OSF/1 i[3456]86-*osf1mk*
3721 HP/Apollo 68k Family m68*-apollo*-sysv*,
3723 m68*-hp-bsd*, m68*-hp-hpux*
3724 Argonaut Risc Chip (ARC) arc-*-*
3725 Mitsubishi D30V d30v-*-*
3726 Fujitsu FR30 fr30-*-elf*
3727 OS/9000 i[34]86-*-os9k
3728 I960 with MON960 i960-*-coff
3730 * MIPS $fp behavior changed
3732 The convenience variable $fp, for the MIPS, now consistently returns
3733 the address of the current frame's base. Previously, depending on the
3734 context, $fp could refer to either $sp or the current frame's base
3735 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3736 The GNU Source-Level Debugger''.
3738 *** Changes in GDB 5.3:
3740 * GNU/Linux shared library multi-threaded performance improved.
3742 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3743 `/proc', in preference to `ptrace' for memory reads. This may result
3744 in an improvement in the start-up time of multi-threaded, shared
3745 library applications when run under GDB. One GDB user writes: ``loads
3746 shared libs like mad''.
3748 * ``gdbserver'' now supports multi-threaded applications on some targets
3750 Support for debugging multi-threaded applications which use
3751 the GNU/Linux LinuxThreads package has been added for
3752 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3753 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3755 * GDB now supports C/C++ preprocessor macros.
3757 GDB now expands preprocessor macro invocations in C/C++ expressions,
3758 and provides various commands for showing macro definitions and how
3761 The new command `macro expand EXPRESSION' expands any macro
3762 invocations in expression, and shows the result.
3764 The new command `show macro MACRO-NAME' shows the definition of the
3765 macro named MACRO-NAME, and where it was defined.
3767 Most compilers don't include information about macros in the debugging
3768 information by default. In GCC 3.1, for example, you need to compile
3769 your program with the options `-gdwarf-2 -g3'. If the macro
3770 information is present in the executable, GDB will read it.
3772 * Multi-arched targets.
3774 DEC Alpha (partial) alpha*-*-*
3775 DEC VAX (partial) vax-*-*
3777 National Semiconductor NS32000 (partial) ns32k-*-*
3778 Motorola 68000 (partial) m68k-*-*
3779 Motorola MCORE mcore-*-*
3783 Fujitsu FRV architecture added by Red Hat frv*-*-*
3786 * New native configurations
3788 Alpha NetBSD alpha*-*-netbsd*
3789 SH NetBSD sh*-*-netbsdelf*
3790 MIPS NetBSD mips*-*-netbsd*
3791 UltraSPARC NetBSD sparc64-*-netbsd*
3793 * OBSOLETE configurations and files
3795 Configurations that have been declared obsolete in this release have
3796 been commented out. Unless there is activity to revive these
3797 configurations, the next release of GDB will have their sources
3798 permanently REMOVED.
3800 Mitsubishi D30V d30v-*-*
3801 OS/9000 i[34]86-*-os9k
3802 IBM AIX PS/2 i[3456]86-*-aix
3803 Fujitsu FR30 fr30-*-elf*
3804 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3805 Argonaut Risc Chip (ARC) arc-*-*
3806 i386 running Mach 3.0 i[3456]86-*-mach3*
3807 i386 running Mach i[3456]86-*-mach*
3808 i386 running OSF/1 i[3456]86-*osf1mk*
3809 HP/Apollo 68k Family m68*-apollo*-sysv*,
3811 m68*-hp-bsd*, m68*-hp-hpux*
3812 I960 with MON960 i960-*-coff
3814 * OBSOLETE languages
3816 CHILL, a Pascal like language used by telecommunications companies.
3818 * REMOVED configurations and files
3820 AMD 29k family via UDI a29k-amd-udi, udi29k
3821 A29K VxWorks a29k-*-vxworks
3822 AMD 29000 embedded, using EBMON a29k-none-none
3823 AMD 29000 embedded with COFF a29k-none-coff
3824 AMD 29000 embedded with a.out a29k-none-aout
3826 testsuite/gdb.hp/gdb.threads-hp/ directory
3828 * New command "set max-user-call-depth <nnn>"
3830 This command allows the user to limit the call depth of user-defined
3831 commands. The default is 1024.
3833 * Changes in FreeBSD/i386 native debugging.
3835 Support for the "generate-core-file" has been added.
3837 * New commands "dump", "append", and "restore".
3839 These commands allow data to be copied from target memory
3840 to a bfd-format or binary file (dump and append), and back
3841 from a file into memory (restore).
3843 * Improved "next/step" support on multi-processor Alpha Tru64.
3845 The previous single-step mechanism could cause unpredictable problems,
3846 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3847 of a software single-step mechanism prevents this.
3849 *** Changes in GDB 5.2.1:
3857 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3858 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3859 Fix, by Joel Brobecker imported from mainline.
3861 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3862 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3863 Fix, by Fred Fish, imported from mainline.
3865 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3866 Surprisingly enough, it works now.
3867 By Michal Ludvig, imported from mainline.
3869 i386 hardware watchpoint support:
3870 avoid misses on second run for some targets.
3871 By Pierre Muller, imported from mainline.
3873 *** Changes in GDB 5.2:
3875 * New command "set trust-readonly-sections on[off]".
3877 This command is a hint that tells gdb that read-only sections
3878 really are read-only (ie. that their contents will not change).
3879 In this mode, gdb will go to the object file rather than the
3880 target to read memory from read-only sections (such as ".text").
3881 This can be a significant performance improvement on some
3882 (notably embedded) targets.
3884 * New command "generate-core-file" (or "gcore").
3886 This new gdb command allows the user to drop a core file of the child
3887 process state at any time. So far it's been implemented only for
3888 GNU/Linux and Solaris, but should be relatively easily ported to other
3889 hosts. Argument is core file name (defaults to core.<pid>).
3891 * New command line option
3893 GDB now accepts --pid or -p followed by a process id.
3895 * Change in command line behavior -- corefiles vs. process ids.
3897 There is a subtle behavior in the way in which GDB handles
3898 command line arguments. The first non-flag argument is always
3899 a program to debug, but the second non-flag argument may either
3900 be a corefile or a process id. Previously, GDB would attempt to
3901 open the second argument as a corefile, and if that failed, would
3902 issue a superfluous error message and then attempt to attach it as
3903 a process. Now, if the second argument begins with a non-digit,
3904 it will be treated as a corefile. If it begins with a digit,
3905 GDB will attempt to attach it as a process, and if no such process
3906 is found, will then attempt to open it as a corefile.
3908 * Changes in ARM configurations.
3910 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3911 configuration is fully multi-arch.
3913 * New native configurations
3915 ARM NetBSD arm*-*-netbsd*
3916 x86 OpenBSD i[3456]86-*-openbsd*
3917 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3918 Sparc64 running FreeBSD sparc64-*-freebsd*
3922 Sanyo XStormy16 xstormy16-elf
3924 * OBSOLETE configurations and files
3926 Configurations that have been declared obsolete in this release have
3927 been commented out. Unless there is activity to revive these
3928 configurations, the next release of GDB will have their sources
3929 permanently REMOVED.
3931 AMD 29k family via UDI a29k-amd-udi, udi29k
3932 A29K VxWorks a29k-*-vxworks
3933 AMD 29000 embedded, using EBMON a29k-none-none
3934 AMD 29000 embedded with COFF a29k-none-coff
3935 AMD 29000 embedded with a.out a29k-none-aout
3937 testsuite/gdb.hp/gdb.threads-hp/ directory
3939 * REMOVED configurations and files
3941 TI TMS320C80 tic80-*-*
3943 PowerPC Solaris powerpcle-*-solaris*
3944 PowerPC Windows NT powerpcle-*-cygwin32
3945 PowerPC Netware powerpc-*-netware*
3946 Harris/CXUX m88k m88*-harris-cxux*
3947 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3948 ns32k-utek-sysv* ns32k-utek-*
3949 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3950 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3951 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3952 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3953 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3955 * Changes to command line processing
3957 The new `--args' feature can be used to specify command-line arguments
3958 for the inferior from gdb's command line.
3960 * Changes to key bindings
3962 There is a new `operate-and-get-next' function bound to `C-o'.
3964 *** Changes in GDB 5.1.1
3966 Fix compile problem on DJGPP.
3968 Fix a problem with floating-point registers on the i386 being
3971 Fix to stop GDB crashing on .debug_str debug info.
3973 Numerous documentation fixes.
3975 Numerous testsuite fixes.
3977 *** Changes in GDB 5.1:
3979 * New native configurations
3981 Alpha FreeBSD alpha*-*-freebsd*
3982 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3983 MIPS GNU/Linux mips*-*-linux*
3984 MIPS SGI Irix 6.x mips*-sgi-irix6*
3985 ia64 AIX ia64-*-aix*
3986 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3990 Motorola 68HC11 and 68HC12 m68hc11-elf
3992 UltraSparc running GNU/Linux sparc64-*-linux*
3994 * OBSOLETE configurations and files
3996 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3997 Harris/CXUX m88k m88*-harris-cxux*
3998 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3999 ns32k-utek-sysv* ns32k-utek-*
4000 TI TMS320C80 tic80-*-*
4002 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4003 PowerPC Solaris powerpcle-*-solaris*
4004 PowerPC Windows NT powerpcle-*-cygwin32
4005 PowerPC Netware powerpc-*-netware*
4006 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4007 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4008 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4009 Apple Macintosh (MPW) host N/A
4011 stuff.c (Program to stuff files into a specially prepared space in kdb)
4012 kdb-start.c (Main loop for the standalone kernel debugger)
4014 Configurations that have been declared obsolete in this release have
4015 been commented out. Unless there is activity to revive these
4016 configurations, the next release of GDB will have their sources
4017 permanently REMOVED.
4019 * REMOVED configurations and files
4021 Altos 3068 m68*-altos-*
4022 Convex c1-*-*, c2-*-*
4024 ARM RISCix arm-*-* (as host)
4028 * GDB has been converted to ISO C.
4030 GDB's source code has been converted to ISO C. In particular, the
4031 sources are fully protoized, and rely on standard headers being
4036 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4038 * The MI enabled by default.
4040 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4041 revised and enabled by default. Packages which use GDB as a debugging
4042 engine behind a UI or another front end are encouraged to switch to
4043 using the GDB/MI interface, instead of the old annotations interface
4044 which is now deprecated.
4046 * Support for debugging Pascal programs.
4048 GDB now includes support for debugging Pascal programs. The following
4049 main features are supported:
4051 - Pascal-specific data types such as sets;
4053 - automatic recognition of Pascal sources based on file-name
4056 - Pascal-style display of data types, variables, and functions;
4058 - a Pascal expression parser.
4060 However, some important features are not yet supported.
4062 - Pascal string operations are not supported at all;
4064 - there are some problems with boolean types;
4066 - Pascal type hexadecimal constants are not supported
4067 because they conflict with the internal variables format;
4069 - support for Pascal objects and classes is not full yet;
4071 - unlike Pascal, GDB is case-sensitive for symbol names.
4073 * Changes in completion.
4075 Commands such as `shell', `run' and `set args', which pass arguments
4076 to inferior programs, now complete on file names, similar to what
4077 users expect at the shell prompt.
4079 Commands which accept locations, such as `disassemble', `print',
4080 `breakpoint', `until', etc. now complete on filenames as well as
4081 program symbols. Thus, if you type "break foob TAB", and the source
4082 files linked into the programs include `foobar.c', that file name will
4083 be one of the candidates for completion. However, file names are not
4084 considered for completion after you typed a colon that delimits a file
4085 name from a name of a function in that file, as in "break foo.c:bar".
4087 `set demangle-style' completes on available demangling styles.
4089 * New platform-independent commands:
4091 It is now possible to define a post-hook for a command as well as a
4092 hook that runs before the command. For more details, see the
4093 documentation of `hookpost' in the GDB manual.
4095 * Changes in GNU/Linux native debugging.
4097 Support for debugging multi-threaded programs has been completely
4098 revised for all platforms except m68k and sparc. You can now debug as
4099 many threads as your system allows you to have.
4101 Attach/detach is supported for multi-threaded programs.
4103 Support for SSE registers was added for x86. This doesn't work for
4104 multi-threaded programs though.
4106 * Changes in MIPS configurations.
4108 Multi-arch support is enabled for all MIPS configurations.
4110 GDB can now be built as native debugger on SGI Irix 6.x systems for
4111 debugging n32 executables. (Debugging 64-bit executables is not yet
4114 * Unified support for hardware watchpoints in all x86 configurations.
4116 Most (if not all) native x86 configurations support hardware-assisted
4117 breakpoints and watchpoints in a unified manner. This support
4118 implements debug register sharing between watchpoints, which allows to
4119 put a virtually infinite number of watchpoints on the same address,
4120 and also supports watching regions up to 16 bytes with several debug
4123 The new maintenance command `maintenance show-debug-regs' toggles
4124 debugging print-outs in functions that insert, remove, and test
4125 watchpoints and hardware breakpoints.
4127 * Changes in the DJGPP native configuration.
4129 New command ``info dos sysinfo'' displays assorted information about
4130 the CPU, OS, memory, and DPMI server.
4132 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4133 display information about segment descriptors stored in GDT, LDT, and
4136 New commands ``info dos pde'' and ``info dos pte'' display entries
4137 from Page Directory and Page Tables (for now works with CWSDPMI only).
4138 New command ``info dos address-pte'' displays the Page Table entry for
4139 a given linear address.
4141 GDB can now pass command lines longer than 126 characters to the
4142 program being debugged (requires an update to the libdbg.a library
4143 which is part of the DJGPP development kit).
4145 DWARF2 debug info is now supported.
4147 It is now possible to `step' and `next' through calls to `longjmp'.
4149 * Changes in documentation.
4151 All GDB documentation was converted to GFDL, the GNU Free
4152 Documentation License.
4154 Tracepoints-related commands are now fully documented in the GDB
4157 TUI, the Text-mode User Interface, is now documented in the manual.
4159 Tracepoints-related commands are now fully documented in the GDB
4162 The "GDB Internals" manual now has an index. It also includes
4163 documentation of `ui_out' functions, GDB coding standards, x86
4164 hardware watchpoints, and memory region attributes.
4166 * GDB's version number moved to ``version.in''
4168 The Makefile variable VERSION has been replaced by the file
4169 ``version.in''. People creating GDB distributions should update the
4170 contents of this file.
4174 GUD support is now a standard part of the EMACS distribution.
4176 *** Changes in GDB 5.0:
4178 * Improved support for debugging FP programs on x86 targets
4180 Unified and much-improved support for debugging floating-point
4181 programs on all x86 targets. In particular, ``info float'' now
4182 displays the FP registers in the same format on all x86 targets, with
4183 greater level of detail.
4185 * Improvements and bugfixes in hardware-assisted watchpoints
4187 It is now possible to watch array elements, struct members, and
4188 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4189 on x86 targets no longer erroneously trigger when the address is
4192 * Improvements in the native DJGPP version of GDB
4194 The distribution now includes all the scripts and auxiliary files
4195 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4196 machines ``out of the box''.
4198 The DJGPP version can now debug programs that use signals. It is
4199 possible to catch signals that happened in the debuggee, deliver
4200 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4201 would kill the program being debugged.) Programs that hook hardware
4202 interrupts (keyboard, timer, etc.) can also be debugged.
4204 It is now possible to debug DJGPP programs that redirect their
4205 standard handles or switch them to raw (as opposed to cooked) mode, or
4206 even close them. The command ``run < foo > bar'' works as expected,
4207 and ``info terminal'' reports useful information about the debuggee's
4208 terminal, including raw/cooked mode, redirection, etc.
4210 The DJGPP version now uses termios functions for console I/O, which
4211 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4214 DOS-style file names with drive letters are now fully supported by
4217 It is now possible to debug DJGPP programs that switch their working
4218 directory. It is also possible to rerun the debuggee any number of
4219 times without restarting GDB; thus, you can use the same setup,
4220 breakpoints, etc. for many debugging sessions.
4222 * New native configurations
4224 ARM GNU/Linux arm*-*-linux*
4225 PowerPC GNU/Linux powerpc-*-linux*
4229 Motorola MCore mcore-*-*
4230 x86 VxWorks i[3456]86-*-vxworks*
4231 PowerPC VxWorks powerpc-*-vxworks*
4232 TI TMS320C80 tic80-*-*
4234 * OBSOLETE configurations
4236 Altos 3068 m68*-altos-*
4237 Convex c1-*-*, c2-*-*
4239 ARM RISCix arm-*-* (as host)
4242 Configurations that have been declared obsolete will be commented out,
4243 but the code will be left in place. If there is no activity to revive
4244 these configurations before the next release of GDB, the sources will
4245 be permanently REMOVED.
4247 * Gould support removed
4249 Support for the Gould PowerNode and NP1 has been removed.
4251 * New features for SVR4
4253 On SVR4 native platforms (such as Solaris), if you attach to a process
4254 without first loading a symbol file, GDB will now attempt to locate and
4255 load symbols from the running process's executable file.
4257 * Many C++ enhancements
4259 C++ support has been greatly improved. Overload resolution now works properly
4260 in almost all cases. RTTI support is on the way.
4262 * Remote targets can connect to a sub-program
4264 A popen(3) style serial-device has been added. This device starts a
4265 sub-process (such as a stand-alone simulator) and then communicates
4266 with that. The sub-program to run is specified using the syntax
4267 ``|<program> <args>'' vis:
4269 (gdb) set remotedebug 1
4270 (gdb) target extended-remote |mn10300-elf-sim program-args
4272 * MIPS 64 remote protocol
4274 A long standing bug in the mips64 remote protocol where by GDB
4275 expected certain 32 bit registers (ex SR) to be transfered as 32
4276 instead of 64 bits has been fixed.
4278 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4279 added to provide backward compatibility with older versions of GDB.
4281 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4283 The command ``set remotebinarydownload'' command has been replaced by
4284 ``set remote X-packet''. Other commands in ``set remote'' family
4285 include ``set remote P-packet''.
4287 * Breakpoint commands accept ranges.
4289 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4290 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4291 ``tracepoint passcount'' also accepts a range of tracepoints.
4293 * ``apropos'' command added.
4295 The ``apropos'' command searches through command names and
4296 documentation strings, printing out matches, making it much easier to
4297 try to find a command that does what you are looking for.
4301 A new machine oriented interface (MI) has been added to GDB. This
4302 interface is designed for debug environments running GDB as a separate
4303 process. This is part of the long term libGDB project. See the
4304 "GDB/MI" chapter of the GDB manual for further information. It can be
4305 enabled by configuring with:
4307 .../configure --enable-gdbmi
4309 *** Changes in GDB-4.18:
4311 * New native configurations
4313 HP-UX 10.20 hppa*-*-hpux10.20
4314 HP-UX 11.x hppa*-*-hpux11.0*
4315 M68K GNU/Linux m68*-*-linux*
4319 Fujitsu FR30 fr30-*-elf*
4320 Intel StrongARM strongarm-*-*
4321 Mitsubishi D30V d30v-*-*
4323 * OBSOLETE configurations
4325 Gould PowerNode, NP1 np1-*-*, pn-*-*
4327 Configurations that have been declared obsolete will be commented out,
4328 but the code will be left in place. If there is no activity to revive
4329 these configurations before the next release of GDB, the sources will
4330 be permanently REMOVED.
4334 As a compatibility experiment, GDB's source files buildsym.h and
4335 buildsym.c have been converted to pure standard C, no longer
4336 containing any K&R compatibility code. We believe that all systems in
4337 use today either come with a standard C compiler, or have a GCC port
4338 available. If this is not true, please report the affected
4339 configuration to bug-gdb@gnu.org immediately. See the README file for
4340 information about getting a standard C compiler if you don't have one
4345 GDB now uses readline 2.2.
4347 * set extension-language
4349 You can now control the mapping between filename extensions and source
4350 languages by using the `set extension-language' command. For instance,
4351 you can ask GDB to treat .c files as C++ by saying
4352 set extension-language .c c++
4353 The command `info extensions' lists all of the recognized extensions
4354 and their associated languages.
4356 * Setting processor type for PowerPC and RS/6000
4358 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4359 you can use the `set processor' command to specify what variant of the
4360 PowerPC family you are debugging. The command
4364 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4365 following PowerPC and RS6000 variants:
4367 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4368 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4370 403GC IBM PowerPC 403GC
4371 505 Motorola PowerPC 505
4372 860 Motorola PowerPC 860 or 850
4373 601 Motorola PowerPC 601
4374 602 Motorola PowerPC 602
4375 603 Motorola/IBM PowerPC 603 or 603e
4376 604 Motorola PowerPC 604 or 604e
4377 750 Motorola/IBM PowerPC 750 or 750
4379 At the moment, this command just tells GDB what to name the
4380 special-purpose processor registers. Since almost all the affected
4381 registers are inaccessible to user-level programs, this command is
4382 only useful for remote debugging in its present form.
4386 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4387 more extensive support for HP-UX. Added features include shared
4388 library support, kernel threads and hardware watchpoints for 11.00,
4389 support for HP's ANSI C and C++ compilers, and a compatibility mode
4390 for xdb and dbx commands.
4394 HP's donation includes the new concept of catchpoints, which is a
4395 generalization of the old catch command. On HP-UX, it is now possible
4396 to catch exec, fork, and vfork, as well as library loading.
4398 This means that the existing catch command has changed; its first
4399 argument now specifies the type of catch to be set up. See the
4400 output of "help catch" for a list of catchpoint types.
4402 * Debugging across forks
4404 On HP-UX, you can choose which process to debug when a fork() happens
4409 HP has donated a curses-based terminal user interface (TUI). To get
4410 it, build with --enable-tui. Although this can be enabled for any
4411 configuration, at present it only works for native HP debugging.
4413 * GDB remote protocol additions
4415 A new protocol packet 'X' that writes binary data is now available.
4416 Default behavior is to try 'X', then drop back to 'M' if the stub
4417 fails to respond. The settable variable `remotebinarydownload'
4418 allows explicit control over the use of 'X'.
4420 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4421 full 64-bit address. The command
4423 set remoteaddresssize 32
4425 can be used to revert to the old behaviour. For existing remote stubs
4426 the change should not be noticed, as the additional address information
4429 In order to assist in debugging stubs, you may use the maintenance
4430 command `packet' to send any text string to the stub. For instance,
4432 maint packet heythere
4434 sends the packet "$heythere#<checksum>". Note that it is very easy to
4435 disrupt a debugging session by sending the wrong packet at the wrong
4438 The compare-sections command allows you to compare section data on the
4439 target to what is in the executable file without uploading or
4440 downloading, by comparing CRC checksums.
4442 * Tracing can collect general expressions
4444 You may now collect general expressions at tracepoints. This requires
4445 further additions to the target-side stub; see tracepoint.c and
4446 doc/agentexpr.texi for further details.
4448 * mask-address variable for Mips
4450 For Mips targets, you may control the zeroing of the upper 32 bits of
4451 a 64-bit address by entering `set mask-address on'. This is mainly
4452 of interest to users of embedded R4xxx and R5xxx processors.
4454 * Higher serial baud rates
4456 GDB's serial code now allows you to specify baud rates 57600, 115200,
4457 230400, and 460800 baud. (Note that your host system may not be able
4458 to achieve all of these rates.)
4462 The i960 configuration now includes an initial implementation of a
4463 builtin simulator, contributed by Jim Wilson.
4466 *** Changes in GDB-4.17:
4468 * New native configurations
4470 Alpha GNU/Linux alpha*-*-linux*
4471 Unixware 2.x i[3456]86-unixware2*
4472 Irix 6.x mips*-sgi-irix6*
4473 PowerPC GNU/Linux powerpc-*-linux*
4474 PowerPC Solaris powerpcle-*-solaris*
4475 Sparc GNU/Linux sparc-*-linux*
4476 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4480 Argonaut Risc Chip (ARC) arc-*-*
4481 Hitachi H8/300S h8300*-*-*
4482 Matsushita MN10200 w/simulator mn10200-*-*
4483 Matsushita MN10300 w/simulator mn10300-*-*
4484 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4485 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4486 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4487 Mitsubishi D10V w/simulator d10v-*-*
4488 Mitsubishi M32R/D w/simulator m32r-*-elf*
4489 Tsqware Sparclet sparclet-*-*
4490 NEC V850 w/simulator v850-*-*
4492 * New debugging protocols
4494 ARM with RDI protocol arm*-*-*
4495 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4496 DDB and LSI variants of PMON protocol mips*-*-*
4497 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4498 PowerPC with SDS protocol powerpc{,le}-*-eabi
4499 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4503 All configurations can now understand and use the DWARF 2 debugging
4504 format. The choice is automatic, if the symbol file contains DWARF 2
4509 GDB now includes basic Java language support. This support is
4510 only useful with Java compilers that produce native machine code.
4512 * solib-absolute-prefix and solib-search-path
4514 For SunOS and SVR4 shared libraries, you may now set the prefix for
4515 loading absolute shared library symbol files, and the search path for
4516 locating non-absolute shared library symbol files.
4518 * Live range splitting
4520 GDB can now effectively debug code for which GCC has performed live
4521 range splitting as part of its optimization. See gdb/doc/LRS for
4522 more details on the expected format of the stabs information.
4526 GDB's support for the GNU Hurd, including thread debugging, has been
4527 updated to work with current versions of the Hurd.
4531 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4532 instruction set. ARM GDB automatically detects when Thumb
4533 instructions are in use, and adjusts disassembly and backtracing
4538 GDB's MIPS target configurations now handle the MIP16 16-bit
4543 GDB now includes support for overlays; if an executable has been
4544 linked such that multiple sections are based at the same address, GDB
4545 will decide which section to use for symbolic info. You can choose to
4546 control the decision manually, using overlay commands, or implement
4547 additional target-side support and use "overlay load-target" to bring
4548 in the overlay mapping. Do "help overlay" for more detail.
4552 The command "info symbol <address>" displays information about
4553 the symbol at the specified address.
4557 The standard remote protocol now includes an extension that allows
4558 asynchronous collection and display of trace data. This requires
4559 extensive support in the target-side debugging stub. Tracing mode
4560 includes a new interaction mode in GDB and new commands: see the
4561 file tracepoint.c for more details.
4565 Configurations for embedded MIPS now include a simulator contributed
4566 by Cygnus Solutions. The simulator supports the instruction sets
4567 of most MIPS variants.
4571 Sparc configurations may now include the ERC32 simulator contributed
4572 by the European Space Agency. The simulator is not built into
4573 Sparc targets by default; configure with --enable-sim to include it.
4577 For target configurations that may include multiple variants of a
4578 basic architecture (such as MIPS and SH), you may now set the
4579 architecture explicitly. "set arch" sets, "info arch" lists
4580 the possible architectures.
4582 *** Changes in GDB-4.16:
4584 * New native configurations
4586 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4587 M68K NetBSD m68k-*-netbsd*
4588 PowerPC AIX 4.x powerpc-*-aix*
4589 PowerPC MacOS powerpc-*-macos*
4590 PowerPC Windows NT powerpcle-*-cygwin32
4591 RS/6000 AIX 4.x rs6000-*-aix4*
4595 ARM with RDP protocol arm-*-*
4596 I960 with MON960 i960-*-coff
4597 MIPS VxWorks mips*-*-vxworks*
4598 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4599 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4601 Matra Sparclet sparclet-*-*
4605 The powerpc-eabi configuration now includes the PSIM simulator,
4606 contributed by Andrew Cagney, with assistance from Mike Meissner.
4607 PSIM is a very elaborate model of the PowerPC, including not only
4608 basic instruction set execution, but also details of execution unit
4609 performance and I/O hardware. See sim/ppc/README for more details.
4613 GDB now works with Solaris 2.5.
4615 * Windows 95/NT native
4617 GDB will now work as a native debugger on Windows 95 and Windows NT.
4618 To build it from source, you must use the "gnu-win32" environment,
4619 which uses a DLL to emulate enough of Unix to run the GNU tools.
4620 Further information, binaries, and sources are available at
4621 ftp.cygnus.com, under pub/gnu-win32.
4623 * dont-repeat command
4625 If a user-defined command includes the command `dont-repeat', then the
4626 command will not be repeated if the user just types return. This is
4627 useful if the command is time-consuming to run, so that accidental
4628 extra keystrokes don't run the same command many times.
4630 * Send break instead of ^C
4632 The standard remote protocol now includes an option to send a break
4633 rather than a ^C to the target in order to interrupt it. By default,
4634 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4636 * Remote protocol timeout
4638 The standard remote protocol includes a new variable `remotetimeout'
4639 that allows you to set the number of seconds before GDB gives up trying
4640 to read from the target. The default value is 2.
4642 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4644 By default GDB will automatically keep track of objects as they are
4645 loaded and unloaded by the dynamic linker. By using the command `set
4646 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4647 when shared library events occur, thus allowing you to set breakpoints
4648 in shared libraries which are explicitly loaded by the inferior.
4650 Note this feature does not work on hpux8. On hpux9 you must link
4651 /usr/lib/end.o into your program. This feature should work
4652 automatically on hpux10.
4654 * Irix 5.x hardware watchpoint support
4656 Irix 5 configurations now support the use of hardware watchpoints.
4658 * Mips protocol "SYN garbage limit"
4660 When debugging a Mips target using the `target mips' protocol, you
4661 may set the number of characters that GDB will ignore by setting
4662 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4663 every character. The default value is 1050.
4665 * Recording and replaying remote debug sessions
4667 If you set `remotelogfile' to the name of a file, gdb will write to it
4668 a recording of a remote debug session. This recording may then be
4669 replayed back to gdb using "gdbreplay". See gdbserver/README for
4670 details. This is useful when you have a problem with GDB while doing
4671 remote debugging; you can make a recording of the session and send it
4672 to someone else, who can then recreate the problem.
4674 * Speedups for remote debugging
4676 GDB includes speedups for downloading and stepping MIPS systems using
4677 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4678 and more efficient S-record downloading.
4680 * Memory use reductions and statistics collection
4682 GDB now uses less memory and reports statistics about memory usage.
4683 Try the `maint print statistics' command, for example.
4685 *** Changes in GDB-4.15:
4687 * Psymtabs for XCOFF
4689 The symbol reader for AIX GDB now uses partial symbol tables. This
4690 can greatly improve startup time, especially for large executables.
4692 * Remote targets use caching
4694 Remote targets now use a data cache to speed up communication with the
4695 remote side. The data cache could lead to incorrect results because
4696 it doesn't know about volatile variables, thus making it impossible to
4697 debug targets which use memory mapped I/O devices. `set remotecache
4698 off' turns the the data cache off.
4700 * Remote targets may have threads
4702 The standard remote protocol now includes support for multiple threads
4703 in the target system, using new protocol commands 'H' and 'T'. See
4704 gdb/remote.c for details.
4708 If GDB is configured with `--enable-netrom', then it will include
4709 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4710 acts as though it is a bank of ROM on the target board, but you can
4711 write into it over the network. GDB's support consists only of
4712 support for fast loading into the emulated ROM; to debug, you must use
4713 another protocol, such as standard remote protocol. The usual
4714 sequence is something like
4716 target nrom <netrom-hostname>
4718 target remote <netrom-hostname>:1235
4722 GDB now includes support for the Apple Macintosh, as a host only. It
4723 may be run as either an MPW tool or as a standalone application, and
4724 it can debug through the serial port. All the usual GDB commands are
4725 available, but to the target command, you must supply "serial" as the
4726 device type instead of "/dev/ttyXX". See mpw-README in the main
4727 directory for more information on how to build. The MPW configuration
4728 scripts */mpw-config.in support only a few targets, and only the
4729 mips-idt-ecoff target has been tested.
4733 GDB configuration now uses autoconf. This is not user-visible,
4734 but does simplify configuration and building.
4738 GDB now supports hpux10.
4740 *** Changes in GDB-4.14:
4742 * New native configurations
4744 x86 FreeBSD i[345]86-*-freebsd
4745 x86 NetBSD i[345]86-*-netbsd
4746 NS32k NetBSD ns32k-*-netbsd
4747 Sparc NetBSD sparc-*-netbsd
4751 A29K VxWorks a29k-*-vxworks
4752 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4753 CPU32 EST-300 emulator m68*-*-est*
4754 PowerPC ELF powerpc-*-elf
4757 * Alpha OSF/1 support for procfs
4759 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4760 possible to attach to running processes. As the mounting of the /proc
4761 filesystem is optional on the Alpha, GDB automatically determines
4762 the availability of /proc during startup. This can lead to problems
4763 if /proc is unmounted after GDB has been started.
4765 * Arguments to user-defined commands
4767 User commands may accept up to 10 arguments separated by whitespace.
4768 Arguments are accessed within the user command via $arg0..$arg9. A
4771 print $arg0 + $arg1 + $arg2
4773 To execute the command use:
4776 Defines the command "adder" which prints the sum of its three arguments.
4777 Note the arguments are text substitutions, so they may reference variables,
4778 use complex expressions, or even perform inferior function calls.
4780 * New `if' and `while' commands
4782 This makes it possible to write more sophisticated user-defined
4783 commands. Both commands take a single argument, which is the
4784 expression to evaluate, and must be followed by the commands to
4785 execute, one per line, if the expression is nonzero, the list being
4786 terminated by the word `end'. The `if' command list may include an
4787 `else' word, which causes the following commands to be executed only
4788 if the expression is zero.
4790 * Fortran source language mode
4792 GDB now includes partial support for Fortran 77. It will recognize
4793 Fortran programs and can evaluate a subset of Fortran expressions, but
4794 variables and functions may not be handled correctly. GDB will work
4795 with G77, but does not yet know much about symbols emitted by other
4798 * Better HPUX support
4800 Most debugging facilities now work on dynamic executables for HPPAs
4801 running hpux9 or later. You can attach to running dynamically linked
4802 processes, but by default the dynamic libraries will be read-only, so
4803 for instance you won't be able to put breakpoints in them. To change
4804 that behavior do the following before running the program:
4810 This will cause the libraries to be mapped private and read-write.
4811 To revert to the normal behavior, do this:
4817 You cannot set breakpoints or examine data in the library until after
4818 the library is loaded if the function/data symbols do not have
4821 GDB can now also read debug symbols produced by the HP C compiler on
4822 HPPAs (sorry, no C++, Fortran or 68k support).
4824 * Target byte order now dynamically selectable
4826 You can choose which byte order to use with a target system, via the
4827 commands "set endian big" and "set endian little", and you can see the
4828 current setting by using "show endian". You can also give the command
4829 "set endian auto", in which case GDB will use the byte order
4830 associated with the executable. Currently, only embedded MIPS
4831 configurations support dynamic selection of target byte order.
4833 * New DOS host serial code
4835 This version uses DPMI interrupts to handle buffered I/O, so you
4836 no longer need to run asynctsr when debugging boards connected to
4839 *** Changes in GDB-4.13:
4841 * New "complete" command
4843 This lists all the possible completions for the rest of the line, if it
4844 were to be given as a command itself. This is intended for use by emacs.
4846 * Trailing space optional in prompt
4848 "set prompt" no longer adds a space for you after the prompt you set. This
4849 allows you to set a prompt which ends in a space or one that does not.
4851 * Breakpoint hit counts
4853 "info break" now displays a count of the number of times the breakpoint
4854 has been hit. This is especially useful in conjunction with "ignore"; you
4855 can ignore a large number of breakpoint hits, look at the breakpoint info
4856 to see how many times the breakpoint was hit, then run again, ignoring one
4857 less than that number, and this will get you quickly to the last hit of
4860 * Ability to stop printing at NULL character
4862 "set print null-stop" will cause GDB to stop printing the characters of
4863 an array when the first NULL is encountered. This is useful when large
4864 arrays actually contain only short strings.
4866 * Shared library breakpoints
4868 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4869 breakpoints in shared libraries before the executable is run.
4871 * Hardware watchpoints
4873 There is a new hardware breakpoint for the watch command for sparclite
4874 targets. See gdb/sparclite/hw_breakpoint.note.
4876 Hardware watchpoints are also now supported under GNU/Linux.
4880 Annotations have been added. These are for use with graphical interfaces,
4881 and are still experimental. Currently only gdba.el uses these.
4883 * Improved Irix 5 support
4885 GDB now works properly with Irix 5.2.
4887 * Improved HPPA support
4889 GDB now works properly with the latest GCC and GAS.
4891 * New native configurations
4893 Sequent PTX4 i[34]86-sequent-ptx4
4894 HPPA running OSF/1 hppa*-*-osf*
4895 Atari TT running SVR4 m68*-*-sysv4*
4896 RS/6000 LynxOS rs6000-*-lynxos*
4900 OS/9000 i[34]86-*-os9k
4901 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4904 * Hitachi SH7000 and E7000-PC ICE support
4906 There is now support for communicating with the Hitachi E7000-PC ICE.
4907 This is available automatically when GDB is configured for the SH.
4911 As usual, a variety of small fixes and improvements, both generic
4912 and configuration-specific. See the ChangeLog for more detail.
4914 *** Changes in GDB-4.12:
4916 * Irix 5 is now supported
4920 GDB-4.12 on the HPPA has a number of changes which make it unable
4921 to debug the output from the currently released versions of GCC and
4922 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4923 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4924 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4927 *** Changes in GDB-4.11:
4929 * User visible changes:
4933 The "set remotedebug" option is now consistent between the mips remote
4934 target, remote targets using the gdb-specific protocol, UDI (AMD's
4935 debug protocol for the 29k) and the 88k bug monitor. It is now an
4936 integer specifying a debug level (normally 0 or 1, but 2 means more
4937 debugging info for the mips target).
4939 * DEC Alpha native support
4941 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4942 debug info, but GDB works fairly well with the DEC compiler and should
4943 work with a future GCC release. See the README file for a few
4944 Alpha-specific notes.
4946 * Preliminary thread implementation
4948 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4950 * LynxOS native and target support for 386
4952 This release has been hosted on LynxOS 2.2, and also can be configured
4953 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4956 * Improvements in C++ mangling/demangling.
4958 This release has much better g++ debugging, specifically in name
4959 mangling/demangling, virtual function calls, print virtual table,
4960 call methods, ...etc.
4962 *** Changes in GDB-4.10:
4964 * User visible changes:
4966 Remote debugging using the GDB-specific (`target remote') protocol now
4967 supports the `load' command. This is only useful if you have some
4968 other way of getting the stub to the target system, and you can put it
4969 somewhere in memory where it won't get clobbered by the download.
4971 Filename completion now works.
4973 When run under emacs mode, the "info line" command now causes the
4974 arrow to point to the line specified. Also, "info line" prints
4975 addresses in symbolic form (as well as hex).
4977 All vxworks based targets now support a user settable option, called
4978 vxworks-timeout. This option represents the number of seconds gdb
4979 should wait for responses to rpc's. You might want to use this if
4980 your vxworks target is, perhaps, a slow software simulator or happens
4981 to be on the far side of a thin network line.
4985 This release contains support for using a DEC alpha as a GDB host for
4986 cross debugging. Native alpha debugging is not supported yet.
4989 *** Changes in GDB-4.9:
4993 This is the first GDB release which is accompanied by a matching testsuite.
4994 The testsuite requires installation of dejagnu, which should be available
4995 via ftp from most sites that carry GNU software.
4999 'Cfront' style demangling has had its name changed to 'ARM' style, to
5000 emphasize that it was written from the specifications in the C++ Annotated
5001 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5002 disclaimers, it still generated too much confusion with users attempting to
5003 use gdb with AT&T cfront.
5007 GDB now uses a standard remote interface to a simulator library.
5008 So far, the library contains simulators for the Zilog Z8001/2, the
5009 Hitachi H8/300, H8/500 and Super-H.
5011 * New targets supported
5013 H8/300 simulator h8300-hitachi-hms or h8300hms
5014 H8/500 simulator h8500-hitachi-hms or h8500hms
5015 SH simulator sh-hitachi-hms or sh
5016 Z8000 simulator z8k-zilog-none or z8ksim
5017 IDT MIPS board over serial line mips-idt-ecoff
5019 Cross-debugging to GO32 targets is supported. It requires a custom
5020 version of the i386-stub.c module which is integrated with the
5021 GO32 memory extender.
5023 * New remote protocols
5025 MIPS remote debugging protocol.
5027 * New source languages supported
5029 This version includes preliminary support for Chill, a Pascal like language
5030 used by telecommunications companies. Chill support is also being integrated
5031 into the GNU compiler, but we don't know when it will be publically available.
5034 *** Changes in GDB-4.8:
5036 * HP Precision Architecture supported
5038 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5039 version of this support was available as a set of patches from the
5040 University of Utah. GDB does not support debugging of programs
5041 compiled with the HP compiler, because HP will not document their file
5042 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5043 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5045 Many problems in the preliminary version have been fixed.
5047 * Faster and better demangling
5049 We have improved template demangling and fixed numerous bugs in the GNU style
5050 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5051 character types (wchar_t) are now supported. Demangling of each symbol is now
5052 only done once, and is cached when the symbol table for a file is read in.
5053 This results in a small increase in memory usage for C programs, a moderate
5054 increase in memory usage for C++ programs, and a fantastic speedup in
5057 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5058 from the specifications in the Annotated Reference Manual, which AT&T's
5059 compiler does not actually implement.
5061 * G++ multiple inheritance compiler problem
5063 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5064 inheritance lattices was reworked to properly discover ambiguities. We
5065 recently found an example which causes this new algorithm to fail in a
5066 very subtle way, producing bad debug information for those classes.
5067 The file 'gcc.patch' (in this directory) can be applied to gcc to
5068 circumvent the problem. A future GCC release will contain a complete
5071 The previous G++ debug info problem (mentioned below for the gdb-4.7
5072 release) is fixed in gcc version 2.3.2.
5074 * Improved configure script
5076 The `configure' script will now attempt to guess your system type if
5077 you don't supply a host system type. The old scheme of supplying a
5078 host system triplet is preferable over using this. All the magic is
5079 done in the new `config.guess' script. Examine it for details.
5081 We have also brought our configure script much more in line with the FSF's
5082 version. It now supports the --with-xxx options. In particular,
5083 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5084 The resulting GDB will not be able to read arbitrary object file formats --
5085 only the format ``expected'' to be used on the configured target system.
5086 We hope to make this the default in a future release.
5088 * Documentation improvements
5090 There's new internal documentation on how to modify GDB, and how to
5091 produce clean changes to the code. We implore people to read it
5092 before submitting changes.
5094 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5095 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5096 `info' files are also provided. To build `info' files from scratch,
5097 you will need the latest `makeinfo' release, which will be available in
5098 a future texinfo-X.Y release.
5100 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5101 We're not sure exactly which versions have this problem, but it has
5102 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5103 or better. If that isn't possible, there is a patch in
5104 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5105 around this problem.
5109 GDB now supports array constants that can be used in expressions typed in by
5110 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5111 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5114 The new directory `gdb/sparclite' contains a program that demonstrates
5115 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5117 * New native hosts supported
5119 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5120 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5122 * New targets supported
5124 AMD 29k family via UDI a29k-amd-udi or udi29k
5126 * New file formats supported
5128 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5129 HPUX core files, and SCO 3.2v2 core files.
5133 Attaching to processes now works again; thanks for the many bug reports.
5135 We have also stomped on a bunch of core dumps caused by
5136 printf_filtered("%s") problems.
5138 We eliminated a copyright problem on the rpc and ptrace header files
5139 for VxWorks, which was discovered at the last minute during the 4.7
5140 release. You should now be able to build a VxWorks GDB.
5142 You can now interrupt gdb while an attached process is running. This
5143 will cause the attached process to stop, and give control back to GDB.
5145 We fixed problems caused by using too many file descriptors
5146 for reading symbols from object files and libraries. This was
5147 especially a problem for programs that used many (~100) shared
5150 The `step' command now only enters a subroutine if there is line number
5151 information for the subroutine. Otherwise it acts like the `next'
5152 command. Previously, `step' would enter subroutines if there was
5153 any debugging information about the routine. This avoids problems
5154 when using `cc -g1' on MIPS machines.
5156 * Internal improvements
5158 GDB's internal interfaces have been improved to make it easier to support
5159 debugging of multiple languages in the future.
5161 GDB now uses a common structure for symbol information internally.
5162 Minimal symbols (derived from linkage symbols in object files), partial
5163 symbols (from a quick scan of debug information), and full symbols
5164 contain a common subset of information, making it easier to write
5165 shared code that handles any of them.
5167 * New command line options
5169 We now accept --silent as an alias for --quiet.
5173 The memory-mapped-malloc library is now licensed under the GNU Library
5174 General Public License.
5176 *** Changes in GDB-4.7:
5178 * Host/native/target split
5180 GDB has had some major internal surgery to untangle the support for
5181 hosts and remote targets. Now, when you configure GDB for a remote
5182 target, it will no longer load in all of the support for debugging
5183 local programs on the host. When fully completed and tested, this will
5184 ensure that arbitrary host/target combinations are possible.
5186 The primary conceptual shift is to separate the non-portable code in
5187 GDB into three categories. Host specific code is required any time GDB
5188 is compiled on that host, regardless of the target. Target specific
5189 code relates to the peculiarities of the target, but can be compiled on
5190 any host. Native specific code is everything else: it can only be
5191 built when the host and target are the same system. Child process
5192 handling and core file support are two common `native' examples.
5194 GDB's use of /proc for controlling Unix child processes is now cleaner.
5195 It has been split out into a single module under the `target_ops' vector,
5196 plus two native-dependent functions for each system that uses /proc.
5198 * New hosts supported
5200 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5201 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5202 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5204 * New targets supported
5206 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5207 68030 and CPU32 m68030-*-*, m68332-*-*
5209 * New native hosts supported
5211 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5212 (386bsd is not well tested yet)
5213 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5215 * New file formats supported
5217 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5218 supports reading of `a.out.adobe' object files, which are an a.out
5219 format extended with minimal information about multiple sections.
5223 `show copying' is the same as the old `info copying'.
5224 `show warranty' is the same as `info warrantee'.
5225 These were renamed for consistency. The old commands continue to work.
5227 `info handle' is a new alias for `info signals'.
5229 You can now define pre-command hooks, which attach arbitrary command
5230 scripts to any command. The commands in the hook will be executed
5231 prior to the user's command. You can also create a hook which will be
5232 executed whenever the program stops. See gdb.texinfo.
5236 We now deal with Cfront style name mangling, and can even extract type
5237 info from mangled symbols. GDB can automatically figure out which
5238 symbol mangling style your C++ compiler uses.
5240 Calling of methods and virtual functions has been improved as well.
5244 The crash that occured when debugging Sun Ansi-C compiled binaries is
5245 fixed. This was due to mishandling of the extra N_SO stabs output
5248 We also finally got Ultrix 4.2 running in house, and fixed core file
5249 support, with help from a dozen people on the net.
5251 John M. Farrell discovered that the reason that single-stepping was so
5252 slow on all of the Mips based platforms (primarily SGI and DEC) was
5253 that we were trying to demangle and lookup a symbol used for internal
5254 purposes on every instruction that was being stepped through. Changing
5255 the name of that symbol so that it couldn't be mistaken for a C++
5256 mangled symbol sped things up a great deal.
5258 Rich Pixley sped up symbol lookups in general by getting much smarter
5259 about when C++ symbol mangling is necessary. This should make symbol
5260 completion (TAB on the command line) much faster. It's not as fast as
5261 we'd like, but it's significantly faster than gdb-4.6.
5265 A new user controllable variable 'call_scratch_address' can
5266 specify the location of a scratch area to be used when GDB
5267 calls a function in the target. This is necessary because the
5268 usual method of putting the scratch area on the stack does not work
5269 in systems that have separate instruction and data spaces.
5271 We integrated changes to support the 29k UDI (Universal Debugger
5272 Interface), but discovered at the last minute that we didn't have all
5273 of the appropriate copyright paperwork. We are working with AMD to
5274 resolve this, and hope to have it available soon.
5278 We have sped up the remote serial line protocol, especially for targets
5279 with lots of registers. It now supports a new `expedited status' ('T')
5280 message which can be used in place of the existing 'S' status message.
5281 This allows the remote stub to send only the registers that GDB
5282 needs to make a quick decision about single-stepping or conditional
5283 breakpoints, eliminating the need to fetch the entire register set for
5284 each instruction being stepped through.
5286 The GDB remote serial protocol now implements a write-through cache for
5287 registers, only re-reading the registers if the target has run.
5289 There is also a new remote serial stub for SPARC processors. You can
5290 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5291 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5292 processor with a serial port.
5296 Configure.in files have become much easier to read and modify. A new
5297 `table driven' format makes it more obvious what configurations are
5298 supported, and what files each one uses.
5302 There is a new opcodes library which will eventually contain all of the
5303 disassembly routines and opcode tables. At present, it only contains
5304 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5305 disassembler (binutils/objdump) to share these routines.
5307 The libiberty library is now copylefted under the GNU Library General
5308 Public License. This allows more liberal use, and was done so libg++
5309 can use it. This makes no difference to GDB, since the Library License
5310 grants all the rights from the General Public License.
5314 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5315 reference to the stabs symbol info used by the debugger. It is (as far
5316 as we know) the only published document on this fascinating topic. We
5317 encourage you to read it, compare it to the stabs information on your
5318 system, and send improvements on the document in general (to
5319 bug-gdb@prep.ai.mit.edu).
5321 And, of course, many bugs have been fixed.
5324 *** Changes in GDB-4.6:
5326 * Better support for C++ function names
5328 GDB now accepts as input the "demangled form" of C++ overloaded function
5329 names and member function names, and can do command completion on such names
5330 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5331 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5332 Make use of command completion, it is your friend.
5334 GDB also now accepts a variety of C++ mangled symbol formats. They are
5335 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5336 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5337 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5338 for the list of formats.
5340 * G++ symbol mangling problem
5342 Recent versions of gcc have a bug in how they emit debugging information for
5343 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5344 directory) can be applied to gcc to fix the problem. Alternatively, if you
5345 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5346 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5347 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5350 * New 'maintenance' command
5352 All of the commands related to hacking GDB internals have been moved out of
5353 the main command set, and now live behind the 'maintenance' command. This
5354 can also be abbreviated as 'mt'. The following changes were made:
5356 dump-me -> maintenance dump-me
5357 info all-breakpoints -> maintenance info breakpoints
5358 printmsyms -> maintenance print msyms
5359 printobjfiles -> maintenance print objfiles
5360 printpsyms -> maintenance print psymbols
5361 printsyms -> maintenance print symbols
5363 The following commands are new:
5365 maintenance demangle Call internal GDB demangler routine to
5366 demangle a C++ link name and prints the result.
5367 maintenance print type Print a type chain for a given symbol
5369 * Change to .gdbinit file processing
5371 We now read the $HOME/.gdbinit file before processing the argv arguments
5372 (e.g. reading symbol files or core files). This allows global parameters to
5373 be set, which will apply during the symbol reading. The ./.gdbinit is still
5374 read after argv processing.
5376 * New hosts supported
5378 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5380 GNU/Linux support i386-unknown-linux or linux
5382 We are also including code to support the HP/PA running BSD and HPUX. This
5383 is almost guaranteed not to work, as we didn't have time to test or build it
5384 for this release. We are including it so that the more adventurous (or
5385 masochistic) of you can play with it. We also had major problems with the
5386 fact that the compiler that we got from HP doesn't support the -g option.
5389 * New targets supported
5391 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5393 * More smarts about finding #include files
5395 GDB now remembers the compilation directory for all include files, and for
5396 all files from which C is generated (like yacc and lex sources). This
5397 greatly improves GDB's ability to find yacc/lex sources, and include files,
5398 especially if you are debugging your program from a directory different from
5399 the one that contains your sources.
5401 We also fixed a bug which caused difficulty with listing and setting
5402 breakpoints in include files which contain C code. (In the past, you had to
5403 try twice in order to list an include file that you hadn't looked at before.)
5405 * Interesting infernals change
5407 GDB now deals with arbitrary numbers of sections, where the symbols for each
5408 section must be relocated relative to that section's landing place in the
5409 target's address space. This work was needed to support ELF with embedded
5410 stabs used by Solaris-2.0.
5412 * Bug fixes (of course!)
5414 There have been loads of fixes for the following things:
5415 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5416 i960, stabs, DOS(GO32), procfs, etc...
5418 See the ChangeLog for details.
5420 *** Changes in GDB-4.5:
5422 * New machines supported (host and target)
5424 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5426 SGI Irix-4.x mips-sgi-irix4 or iris4
5428 * New malloc package
5430 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5431 Mmalloc is capable of handling mutiple heaps of memory. It is also
5432 capable of saving a heap to a file, and then mapping it back in later.
5433 This can be used to greatly speedup the startup of GDB by using a
5434 pre-parsed symbol table which lives in a mmalloc managed heap. For
5435 more details, please read mmalloc/mmalloc.texi.
5439 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5440 'help info proc' for details.
5442 * MIPS ecoff symbol table format
5444 The code that reads MIPS symbol table format is now supported on all hosts.
5445 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5448 * File name changes for MS-DOS
5450 Many files in the config directories have been renamed to make it easier to
5451 support GDB on MS-DOSe systems (which have very restrictive file name
5452 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5453 environment) is close to working but has some remaining problems. Note
5454 that debugging of DOS programs is not supported, due to limitations
5455 in the ``operating system'', but it can be used to host cross-debugging.
5457 * Cross byte order fixes
5459 Many fixes have been made to support cross debugging of Sparc and MIPS
5460 targets from hosts whose byte order differs.
5462 * New -mapped and -readnow options
5464 If memory-mapped files are available on your system through the 'mmap'
5465 system call, you can use the -mapped option on the `file' or
5466 `symbol-file' commands to cause GDB to write the symbols from your
5467 program into a reusable file. If the program you are debugging is
5468 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5469 Future GDB debugging sessions will notice the presence of this file,
5470 and will quickly map in symbol information from it, rather than reading
5471 the symbol table from the executable program. Using the '-mapped'
5472 option in a GDB `file' or `symbol-file' command has the same effect as
5473 starting GDB with the '-mapped' command-line option.
5475 You can cause GDB to read the entire symbol table immediately by using
5476 the '-readnow' option with any of the commands that load symbol table
5477 information (or on the GDB command line). This makes the command
5478 slower, but makes future operations faster.
5480 The -mapped and -readnow options are typically combined in order to
5481 build a `fred.syms' file that contains complete symbol information.
5482 A simple GDB invocation to do nothing but build a `.syms' file for future
5485 gdb -batch -nx -mapped -readnow programname
5487 The `.syms' file is specific to the host machine on which GDB is run.
5488 It holds an exact image of GDB's internal symbol table. It cannot be
5489 shared across multiple host platforms.
5491 * longjmp() handling
5493 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5494 siglongjmp() without losing control. This feature has not yet been ported to
5495 all systems. It currently works on many 386 platforms, all MIPS-based
5496 platforms (SGI, DECstation, etc), and Sun3/4.
5500 Preliminary work has been put in to support the new Solaris OS from Sun. At
5501 this time, it can control and debug processes, but it is not capable of
5506 As always, many many bug fixes. The major areas were with g++, and mipsread.
5507 People using the MIPS-based platforms should experience fewer mysterious
5508 crashes and trashed symbol tables.
5510 *** Changes in GDB-4.4:
5512 * New machines supported (host and target)
5514 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5516 BSD Reno on Vax vax-dec-bsd
5517 Ultrix on Vax vax-dec-ultrix
5519 * New machines supported (target)
5521 AMD 29000 embedded, using EBMON a29k-none-none
5525 GDB continues to improve its handling of C++. `References' work better.
5526 The demangler has also been improved, and now deals with symbols mangled as
5527 per the Annotated C++ Reference Guide.
5529 GDB also now handles `stabs' symbol information embedded in MIPS
5530 `ecoff' symbol tables. Since the ecoff format was not easily
5531 extensible to handle new languages such as C++, this appeared to be a
5532 good way to put C++ debugging info into MIPS binaries. This option
5533 will be supported in the GNU C compiler, version 2, when it is
5536 * New features for SVR4
5538 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5539 shared libraries. Debugging dynamically linked programs should present
5540 only minor differences from debugging statically linked programs.
5542 The `info proc' command will print out information about any process
5543 on an SVR4 system (including the one you are debugging). At the moment,
5544 it prints the address mappings of the process.
5546 If you bring up GDB on another SVR4 system, please send mail to
5547 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5549 * Better dynamic linking support in SunOS
5551 Reading symbols from shared libraries which contain debugging symbols
5552 now works properly. However, there remain issues such as automatic
5553 skipping of `transfer vector' code during function calls, which
5554 make it harder to debug code in a shared library, than to debug the
5555 same code linked statically.
5559 GDB is now using the latest `getopt' routines from the FSF. This
5560 version accepts the -- prefix for options with long names. GDB will
5561 continue to accept the old forms (-option and +option) as well.
5562 Various single letter abbreviations for options have been explicity
5563 added to the option table so that they won't get overshadowed in the
5564 future by other options that begin with the same letter.
5568 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5569 Many assorted bugs have been handled. Many more remain to be handled.
5570 See the various ChangeLog files (primarily in gdb and bfd) for details.
5573 *** Changes in GDB-4.3:
5575 * New machines supported (host and target)
5577 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5578 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5579 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5581 * Almost SCO Unix support
5583 We had hoped to support:
5584 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5585 (except for core file support), but we discovered very late in the release
5586 that it has problems with process groups that render gdb unusable. Sorry
5587 about that. I encourage people to fix it and post the fixes.
5589 * Preliminary ELF and DWARF support
5591 GDB can read ELF object files on System V Release 4, and can handle
5592 debugging records for C, in DWARF format, in ELF files. This support
5593 is preliminary. If you bring up GDB on another SVR4 system, please
5594 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5599 GDB now uses the latest `readline' library. One user-visible change
5600 is that two tabs will list possible command completions, which previously
5601 required typing M-? (meta-question mark, or ESC ?).
5605 The `stepi' bug that many of you noticed has been squashed.
5606 Many bugs in C++ have been handled. Many more remain to be handled.
5607 See the various ChangeLog files (primarily in gdb and bfd) for details.
5609 * State of the MIPS world (in case you wondered):
5611 GDB can understand the symbol tables emitted by the compilers
5612 supplied by most vendors of MIPS-based machines, including DEC. These
5613 symbol tables are in a format that essentially nobody else uses.
5615 Some versions of gcc come with an assembler post-processor called
5616 mips-tfile. This program is required if you want to do source-level
5617 debugging of gcc-compiled programs. I believe FSF does not ship
5618 mips-tfile with gcc version 1, but it will eventually come with gcc
5621 Debugging of g++ output remains a problem. g++ version 1.xx does not
5622 really support it at all. (If you're lucky, you should be able to get
5623 line numbers and stack traces to work, but no parameters or local
5624 variables.) With some work it should be possible to improve the
5627 When gcc version 2 is released, you will have somewhat better luck.
5628 However, even then you will get confusing results for inheritance and
5631 We will eventually provide full debugging of g++ output on
5632 DECstations. This will probably involve some kind of stabs-in-ecoff
5633 encapulation, but the details have not been worked out yet.
5636 *** Changes in GDB-4.2:
5638 * Improved configuration
5640 Only one copy of `configure' exists now, and it is not self-modifying.
5641 Porting BFD is simpler.
5645 The `step' and `next' commands now only stop at the first instruction
5646 of a source line. This prevents the multiple stops that used to occur
5647 in switch statements, for-loops, etc. `Step' continues to stop if a
5648 function that has debugging information is called within the line.
5652 Lots of small bugs fixed. More remain.
5654 * New host supported (not target)
5656 Intel 386 PC clone running Mach i386-none-mach
5659 *** Changes in GDB-4.1:
5661 * Multiple source language support
5663 GDB now has internal scaffolding to handle several source languages.
5664 It determines the type of each source file from its filename extension,
5665 and will switch expression parsing and number formatting to match the
5666 language of the function in the currently selected stack frame.
5667 You can also specifically set the language to be used, with
5668 `set language c' or `set language modula-2'.
5672 GDB now has preliminary support for the GNU Modula-2 compiler,
5673 currently under development at the State University of New York at
5674 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5675 continue through the fall of 1991 and into 1992.
5677 Other Modula-2 compilers are currently not supported, and attempting to
5678 debug programs compiled with them will likely result in an error as the
5679 symbol table is read. Feel free to work on it, though!
5681 There are hooks in GDB for strict type checking and range checking,
5682 in the `Modula-2 philosophy', but they do not currently work.
5686 GDB can now write to executable and core files (e.g. patch
5687 a variable's value). You must turn this switch on, specify
5688 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5689 by assigning a new value to a variable. Modifications take
5692 * Automatic SunOS shared library reading
5694 When you run your program, GDB automatically determines where its
5695 shared libraries (if any) have been loaded, and reads their symbols.
5696 The `share' command is no longer needed. This also works when
5697 examining core files.
5701 You can specify the number of lines that the `list' command shows.
5704 * New machines supported (host and target)
5706 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5707 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5708 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5710 * New hosts supported (not targets)
5712 IBM RT/PC: romp-ibm-aix or rtpc
5714 * New targets supported (not hosts)
5716 AMD 29000 embedded with COFF a29k-none-coff
5717 AMD 29000 embedded with a.out a29k-none-aout
5718 Ultracomputer remote kernel debug a29k-nyu-kern
5720 * New remote interfaces
5726 *** Changes in GDB-4.0:
5730 Wide output is wrapped at good places to make the output more readable.
5732 Gdb now supports cross-debugging from a host machine of one type to a
5733 target machine of another type. Communication with the target system
5734 is over serial lines. The ``target'' command handles connecting to the
5735 remote system; the ``load'' command will download a program into the
5736 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5737 also supports debugging of realtime processes running under VxWorks,
5738 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5739 stub on the target system.
5741 New CPUs supported include the AMD 29000 and Intel 960.
5743 GDB now reads object files and symbol tables via a ``binary file''
5744 library, which allows a single copy of GDB to debug programs of multiple
5745 object file types such as a.out and coff.
5747 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5748 refcard.dvi and refcard.ps are available to format it).
5751 * Control-Variable user interface simplified
5753 All variables that control the operation of the debugger can be set
5754 by the ``set'' command, and displayed by the ``show'' command.
5756 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5757 ``Show prompt'' produces the response:
5758 Gdb's prompt is new-gdb=>.
5760 What follows are the NEW set commands. The command ``help set'' will
5761 print a complete list of old and new set commands. ``help set FOO''
5762 will give a longer description of the variable FOO. ``show'' will show
5763 all of the variable descriptions and their current settings.
5765 confirm on/off: Enables warning questions for operations that are
5766 hard to recover from, e.g. rerunning the program while
5767 it is already running. Default is ON.
5769 editing on/off: Enables EMACS style command line editing
5770 of input. Previous lines can be recalled with
5771 control-P, the current line can be edited with control-B,
5772 you can search for commands with control-R, etc.
5775 history filename NAME: NAME is where the gdb command history
5776 will be stored. The default is .gdb_history,
5777 or the value of the environment variable
5780 history size N: The size, in commands, of the command history. The
5781 default is 256, or the value of the environment variable
5784 history save on/off: If this value is set to ON, the history file will
5785 be saved after exiting gdb. If set to OFF, the
5786 file will not be saved. The default is OFF.
5788 history expansion on/off: If this value is set to ON, then csh-like
5789 history expansion will be performed on
5790 command line input. The default is OFF.
5792 radix N: Sets the default radix for input and output. It can be set
5793 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5794 in the current radix, so "set radix 10" is always a no-op.
5796 height N: This integer value is the number of lines on a page. Default
5797 is 24, the current `stty rows'' setting, or the ``li#''
5798 setting from the termcap entry matching the environment
5801 width N: This integer value is the number of characters on a line.
5802 Default is 80, the current `stty cols'' setting, or the ``co#''
5803 setting from the termcap entry matching the environment
5806 Note: ``set screensize'' is obsolete. Use ``set height'' and
5807 ``set width'' instead.
5809 print address on/off: Print memory addresses in various command displays,
5810 such as stack traces and structure values. Gdb looks
5811 more ``symbolic'' if you turn this off; it looks more
5812 ``machine level'' with it on. Default is ON.
5814 print array on/off: Prettyprint arrays. New convenient format! Default
5817 print demangle on/off: Print C++ symbols in "source" form if on,
5820 print asm-demangle on/off: Same, for assembler level printouts
5823 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5826 * Support for Epoch Environment.
5828 The epoch environment is a version of Emacs v18 with windowing. One
5829 new command, ``inspect'', is identical to ``print'', except that if you
5830 are running in the epoch environment, the value is printed in its own
5834 * Support for Shared Libraries
5836 GDB can now debug programs and core files that use SunOS shared libraries.
5837 Symbols from a shared library cannot be referenced
5838 before the shared library has been linked with the program (this
5839 happens after you type ``run'' and before the function main() is entered).
5840 At any time after this linking (including when examining core files
5841 from dynamically linked programs), gdb reads the symbols from each
5842 shared library when you type the ``sharedlibrary'' command.
5843 It can be abbreviated ``share''.
5845 sharedlibrary REGEXP: Load shared object library symbols for files
5846 matching a unix regular expression. No argument
5847 indicates to load symbols for all shared libraries.
5849 info sharedlibrary: Status of loaded shared libraries.
5854 A watchpoint stops execution of a program whenever the value of an
5855 expression changes. Checking for this slows down execution
5856 tremendously whenever you are in the scope of the expression, but is
5857 quite useful for catching tough ``bit-spreader'' or pointer misuse
5858 problems. Some machines such as the 386 have hardware for doing this
5859 more quickly, and future versions of gdb will use this hardware.
5861 watch EXP: Set a watchpoint (breakpoint) for an expression.
5863 info watchpoints: Information about your watchpoints.
5865 delete N: Deletes watchpoint number N (same as breakpoints).
5866 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5867 enable N: Re-enables watchpoint number N (same as breakpoints).
5870 * C++ multiple inheritance
5872 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5875 * C++ exception handling
5877 Gdb now supports limited C++ exception handling. Besides the existing
5878 ability to breakpoint on an exception handler, gdb can breakpoint on
5879 the raising of an exception (before the stack is peeled back to the
5882 catch FOO: If there is a FOO exception handler in the dynamic scope,
5883 set a breakpoint to catch exceptions which may be raised there.
5884 Multiple exceptions (``catch foo bar baz'') may be caught.
5886 info catch: Lists all exceptions which may be caught in the
5887 current stack frame.
5890 * Minor command changes
5892 The command ``call func (arg, arg, ...)'' now acts like the print
5893 command, except it does not print or save a value if the function's result
5894 is void. This is similar to dbx usage.
5896 The ``up'' and ``down'' commands now always print the frame they end up
5897 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5898 frames without printing.
5900 * New directory command
5902 'dir' now adds directories to the FRONT of the source search path.
5903 The path starts off empty. Source files that contain debug information
5904 about the directory in which they were compiled can be found even
5905 with an empty path; Sun CC and GCC include this information. If GDB can't
5906 find your source file in the current directory, type "dir .".
5908 * Configuring GDB for compilation
5910 For normal use, type ``./configure host''. See README or gdb.texinfo
5913 GDB now handles cross debugging. If you are remotely debugging between
5914 two different machines, type ``./configure host -target=targ''.
5915 Host is the machine where GDB will run; targ is the machine
5916 where the program that you are debugging will run.