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 *** Changes in GDB 7.9
23 * GDB now supports hardware watchpoints on x86 GNU Hurd.
27 ** You can now access frame registers from Python scripts.
28 ** New attribute 'producer' for gdb.Symtab objects.
29 ** gdb.Objfile objects have a new attribute "progspace",
30 which is the gdb.Progspace object of the containing program space.
31 ** gdb.Objfile objects have a new attribute "owner".
32 ** gdb.Objfile objects have a new attribute "build_id",
33 which is the build ID generated when the file was built.
34 ** gdb.Objfile objects have a new method "add_separate_debug_file".
35 ** A new event "gdb.clear_objfiles" has been added, triggered when
36 selecting a new file to debug.
37 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
38 ** New function gdb.lookup_objfile.
40 New events which are triggered when GDB modifies the state of the
43 ** gdb.events.inferior_call_pre: Function call is about to be made.
44 ** gdb.events.inferior_call_post: Function call has just been made.
45 ** gdb.events.memory_changed: A memory location has been altered.
46 ** gdb.events.register_changed: A register has been altered.
48 * New Python-based convenience functions:
50 ** $_caller_is(name [, number_of_frames])
51 ** $_caller_matches(regexp [, number_of_frames])
52 ** $_any_caller_is(name [, number_of_frames])
53 ** $_any_caller_matches(regexp [, number_of_frames])
55 * GDB now supports the compilation and injection of source code into
56 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
57 to compile the source code to object code, and if successful, inject
58 and execute that code within the current context of the inferior.
59 Currently the C language is supported. The commands used to
60 interface with this new feature are:
62 compile code [-raw|-r] [--] [source code]
63 compile file [-raw|-r] filename
67 demangle [-l language] [--] name
68 Demangle "name" in the specified language, or the current language
69 if elided. This command is renamed from the "maint demangle" command.
70 The latter is kept as a no-op to avoid "maint demangle" being interpreted
71 as "maint demangler-warning".
73 queue-signal signal-name-or-number
74 Queue a signal to be delivered to the thread when it is resumed.
76 add-auto-load-scripts-directory directory
77 Add entries to the list of directories from which to load auto-loaded
80 maint print user-registers
81 List all currently available "user" registers.
83 compile code [-r|-raw] [--] [source code]
84 Compile, inject, and execute in the inferior the executable object
85 code produced by compiling the provided source code.
87 compile file [-r|-raw] filename
88 Compile and inject into the inferior the executable object code
89 produced by compiling the source code stored in the filename
92 * On resume, GDB now always passes the signal the program had stopped
93 for to the thread the signal was sent to, even if the user changed
94 threads before resuming. Previously GDB would often (but not
95 always) deliver the signal to the thread that happens to be current
98 * Conversely, the "signal" command now consistently delivers the
99 requested signal to the current thread. GDB now asks for
100 confirmation if the program had stopped for a signal and the user
101 switched threads meanwhile.
103 * "breakpoint always-inserted" modes "off" and "auto" merged.
105 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
106 won't remove breakpoints from the target until all threads stop,
107 even in non-stop mode. The "auto" mode has been removed, and "off"
108 is now the default mode.
112 set debug symbol-lookup
113 show debug symbol-lookup
114 Control display of debugging info regarding symbol lookup.
118 ** The -list-thread-groups command outputs an exit-code field for
119 inferiors that have exited.
123 MIPS SDE mips*-sde*-elf*
127 Support for these obsolete configurations has been removed.
129 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
130 SGI Irix-5.x mips-*-irix5*
131 SGI Irix-6.x mips-*-irix6*
132 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
133 VAX running Ultrix vax-*-ultrix*
135 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
136 and "assf"), have been removed. Use the "sharedlibrary" command, or
137 its alias "share", instead.
139 *** Changes in GDB 7.8
141 * New command line options
144 This is an alias for the --data-directory option.
146 * GDB supports printing and modifying of variable length automatic arrays
147 as specified in ISO C99.
149 * The ARM simulator now supports instruction level tracing
150 with or without disassembly.
154 GDB now has support for scripting using Guile. Whether this is
155 available is determined at configure time.
156 Guile version 2.0 or greater is required.
157 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
159 * New commands (for set/show, see "New options" below)
163 Invoke CODE by passing it to the Guile interpreter.
167 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
169 info auto-load guile-scripts [regexp]
170 Print the list of automatically loaded Guile scripts.
172 * The source command is now capable of sourcing Guile scripts.
173 This feature is dependent on the debugger being built with Guile support.
177 set print symbol-loading (off|brief|full)
178 show print symbol-loading
179 Control whether to print informational messages when loading symbol
180 information for a file. The default is "full", but when debugging
181 programs with large numbers of shared libraries the amount of output
184 set guile print-stack (none|message|full)
185 show guile print-stack
186 Show a stack trace when an error is encountered in a Guile script.
188 set auto-load guile-scripts (on|off)
189 show auto-load guile-scripts
190 Control auto-loading of Guile script files.
192 maint ada set ignore-descriptive-types (on|off)
193 maint ada show ignore-descriptive-types
194 Control whether the debugger should ignore descriptive types in Ada
195 programs. The default is not to ignore the descriptive types. See
196 the user manual for more details on descriptive types and the intended
197 usage of this option.
199 set auto-connect-native-target
201 Control whether GDB is allowed to automatically connect to the
202 native target for the run, attach, etc. commands when not connected
203 to any target yet. See also "target native" below.
205 set record btrace replay-memory-access (read-only|read-write)
206 show record btrace replay-memory-access
207 Control what memory accesses are allowed during replay.
209 maint set target-async (on|off)
210 maint show target-async
211 This controls whether GDB targets operate in synchronous or
212 asynchronous mode. Normally the default is asynchronous, if it is
213 available; but this can be changed to more easily debug problems
214 occurring only in synchronous mode.
216 set mi-async (on|off)
218 Control whether MI asynchronous mode is preferred. This supersedes
219 "set target-async" of previous GDB versions.
221 * "set target-async" is deprecated as a CLI option and is now an alias
222 for "set mi-async" (only puts MI into async mode).
224 * Background execution commands (e.g., "c&", "s&", etc.) are now
225 possible ``out of the box'' if the target supports them. Previously
226 the user would need to explicitly enable the possibility with the
227 "set target-async on" command.
229 * New features in the GDB remote stub, GDBserver
231 ** New option --debug-format=option1[,option2,...] allows one to add
232 additional text to each output. At present only timestamps
233 are supported: --debug-format=timestamps.
234 Timestamps can also be turned on with the
235 "monitor set debug-format timestamps" command from GDB.
237 * The 'record instruction-history' command now starts counting instructions
238 at one. This also affects the instruction ranges reported by the
239 'record function-call-history' command when given the /i modifier.
241 * The command 'record function-call-history' supports a new modifier '/c' to
242 indent the function names based on their call stack depth.
243 The fields for the '/i' and '/l' modifier have been reordered.
244 The source line range is now prefixed with 'at'.
245 The instruction range is now prefixed with 'inst'.
246 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
247 "record instruction-history" and "list" commands.
249 * The ranges given as arguments to the 'record function-call-history' and
250 'record instruction-history' commands are now inclusive.
252 * The btrace record target now supports the 'record goto' command.
253 For locations inside the execution trace, the back trace is computed
254 based on the information stored in the execution trace.
256 * The btrace record target supports limited reverse execution and replay.
257 The target does not record data and therefore does not allow reading
260 * The "catch syscall" command now works on s390*-linux* targets.
262 * The "compare-sections" command is no longer specific to target
263 remote. It now works with all targets.
265 * All native targets are now consistently called "native".
266 Consequently, the "target child", "target GNU", "target djgpp",
267 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
268 commands have been replaced with "target native". The QNX/NTO port
269 leaves the "procfs" target in place and adds a "native" target for
270 consistency with other ports. The impact on users should be minimal
271 as these commands previously either throwed an error, or were
272 no-ops. The target's name is visible in the output of the following
273 commands: "help target", "info target", "info files", "maint print
276 * The "target native" command now connects to the native target. This
277 can be used to launch native programs even when "set
278 auto-connect-native-target" is set to off.
280 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
282 * Support for Intel(R) AVX-512 registers on GNU/Linux.
283 Support displaying and modifying Intel(R) AVX-512 registers
284 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
288 qXfer:btrace:read's annex
289 The qXfer:btrace:read packet supports a new annex 'delta' to read
290 branch trace incrementally.
294 ** Valid Python operations on gdb.Value objects representing
295 structs/classes invoke the corresponding overloaded operators if
297 ** New `Xmethods' feature in the Python API. Xmethods are
298 additional methods or replacements for existing methods of a C++
299 class. This feature is useful for those cases where a method
300 defined in C++ source code could be inlined or optimized out by
301 the compiler, making it unavailable to GDB.
304 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
306 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
307 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
308 its alias "share", instead.
310 * The commands "set remotebaud" and "show remotebaud" are no longer
311 supported. Use "set serial baud" and "show serial baud" (respectively)
316 ** A new option "-gdb-set mi-async" replaces "-gdb-set
317 target-async". The latter is left as a deprecated alias of the
318 former for backward compatibility. If the target supports it,
319 CLI background execution commands are now always possible by
320 default, independently of whether the frontend stated a
321 preference for asynchronous execution with "-gdb-set mi-async".
322 Previously "-gdb-set target-async off" affected both MI execution
323 commands and CLI execution commands.
325 *** Changes in GDB 7.7
327 * Improved support for process record-replay and reverse debugging on
328 arm*-linux* targets. Support for thumb32 and syscall instruction
329 recording has been added.
331 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
333 * GDB now supports Fission DWP file format version 2.
334 http://gcc.gnu.org/wiki/DebugFission
336 * New convenience function "$_isvoid", to check whether an expression
337 is void. A void expression is an expression where the type of the
338 result is "void". For example, some convenience variables may be
339 "void" when evaluated (e.g., "$_exitcode" before the execution of
340 the program being debugged; or an undefined convenience variable).
341 Another example, when calling a function whose return type is
344 * The "maintenance print objfiles" command now takes an optional regexp.
346 * The "catch syscall" command now works on arm*-linux* targets.
348 * GDB now consistently shows "<not saved>" when printing values of
349 registers the debug info indicates have not been saved in the frame
350 and there's nowhere to retrieve them from
351 (callee-saved/call-clobbered registers):
356 (gdb) info registers rax
359 Before, the former would print "<optimized out>", and the latter
360 "*value not available*".
362 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
367 ** Frame filters and frame decorators have been added.
368 ** Temporary breakpoints are now supported.
369 ** Line tables representation has been added.
370 ** New attribute 'parent_type' for gdb.Field objects.
371 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
372 ** New attribute 'name' for gdb.Type objects.
376 Nios II ELF nios2*-*-elf
377 Nios II GNU/Linux nios2*-*-linux
378 Texas Instruments MSP430 msp430*-*-elf
380 * Removed native configurations
382 Support for these a.out NetBSD and OpenBSD obsolete configurations has
383 been removed. ELF variants of these configurations are kept supported.
385 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
386 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
387 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
388 i[34567]86-*-openbsd3.[0-3]
389 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
390 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
391 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
395 Like "catch throw", but catches a re-thrown exception.
397 Renamed from old "maint check-symtabs".
399 Perform consistency checks on symtabs.
401 Expand symtabs matching an optional regexp.
404 Display the details of GDB configure-time options.
406 maint set|show per-command
407 maint set|show per-command space
408 maint set|show per-command time
409 maint set|show per-command symtab
410 Enable display of per-command gdb resource usage.
412 remove-symbol-file FILENAME
413 remove-symbol-file -a ADDRESS
414 Remove a symbol file added via add-symbol-file. The file to remove
415 can be identified by its filename or by an address that lies within
416 the boundaries of this symbol file in memory.
419 info exceptions REGEXP
420 Display the list of Ada exceptions defined in the program being
421 debugged. If provided, only the exceptions whose names match REGEXP
426 set debug symfile off|on
428 Control display of debugging info regarding reading symbol files and
429 symbol tables within those files
431 set print raw frame-arguments
432 show print raw frame-arguments
433 Set/show whether to print frame arguments in raw mode,
434 disregarding any defined pretty-printers.
436 set remote trace-status-packet
437 show remote trace-status-packet
438 Set/show the use of remote protocol qTStatus packet.
442 Control display of debugging messages related to Nios II targets.
446 Control whether target-assisted range stepping is enabled.
448 set startup-with-shell
449 show startup-with-shell
450 Specifies whether Unix child processes are started via a shell or
455 Use the target memory cache for accesses to the code segment. This
456 improves performance of remote debugging (particularly disassembly).
458 * You can now use a literal value 'unlimited' for options that
459 interpret 0 or -1 as meaning "unlimited". E.g., "set
460 trace-buffer-size unlimited" is now an alias for "set
461 trace-buffer-size -1" and "set height unlimited" is now an alias for
464 * The "set debug symtab-create" debugging option of GDB has been changed to
465 accept a verbosity level. 0 means "off", 1 provides basic debugging
466 output, and values of 2 or greater provides more verbose output.
468 * New command-line options
470 Display the details of GDB configure-time options.
472 * The command 'tsave' can now support new option '-ctf' to save trace
473 buffer in Common Trace Format.
475 * Newly installed $prefix/bin/gcore acts as a shell interface for the
478 * GDB now implements the the C++ 'typeid' operator.
480 * The new convenience variable $_exception holds the exception being
481 thrown or caught at an exception-related catchpoint.
483 * The exception-related catchpoints, like "catch throw", now accept a
484 regular expression which can be used to filter exceptions by type.
486 * The new convenience variable $_exitsignal is automatically set to
487 the terminating signal number when the program being debugged dies
488 due to an uncaught signal.
492 ** All MI commands now accept an optional "--language" option.
493 Support for this feature can be verified by using the "-list-features"
494 command, which should contain "language-option".
496 ** The new command -info-gdb-mi-command allows the user to determine
497 whether a GDB/MI command is supported or not.
499 ** The "^error" result record returned when trying to execute an undefined
500 GDB/MI command now provides a variable named "code" whose content is the
501 "undefined-command" error code. Support for this feature can be verified
502 by using the "-list-features" command, which should contain
503 "undefined-command-error-code".
505 ** The -trace-save MI command can optionally save trace buffer in Common
508 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
510 ** The command -data-list-register-values now accepts an optional
511 "--skip-unavailable" option. When used, only the available registers
514 ** The new command -trace-frame-collected dumps collected variables,
515 computed expressions, tvars, memory and registers in a traceframe.
517 ** The commands -stack-list-locals, -stack-list-arguments and
518 -stack-list-variables now accept an option "--skip-unavailable".
519 When used, only the available locals or arguments are displayed.
521 ** The -exec-run command now accepts an optional "--start" option.
522 When used, the command follows the same semantics as the "start"
523 command, stopping the program's execution at the start of its
524 main subprogram. Support for this feature can be verified using
525 the "-list-features" command, which should contain
526 "exec-run-start-option".
528 ** The new commands -catch-assert and -catch-exceptions insert
529 catchpoints stopping the program when Ada exceptions are raised.
531 ** The new command -info-ada-exceptions provides the equivalent of
532 the new "info exceptions" command.
534 * New system-wide configuration scripts
535 A GDB installation now provides scripts suitable for use as system-wide
536 configuration scripts for the following systems:
540 * GDB now supports target-assigned range stepping with remote targets.
541 This improves the performance of stepping source lines by reducing
542 the number of control packets from/to GDB. See "New remote packets"
545 * GDB now understands the element 'tvar' in the XML traceframe info.
546 It has the id of the collected trace state variables.
548 * On S/390 targets that provide the transactional-execution feature,
549 the program interruption transaction diagnostic block (TDB) is now
550 represented as a number of additional "registers" in GDB.
556 The vCont packet supports a new 'r' action, that tells the remote
557 stub to step through an address range itself, without GDB
558 involvemement at each single-step.
560 qXfer:libraries-svr4:read's annex
561 The previously unused annex of the qXfer:libraries-svr4:read packet
562 is now used to support passing an argument list. The remote stub
563 reports support for this argument list to GDB's qSupported query.
564 The defined arguments are "start" and "prev", used to reduce work
565 necessary for library list updating, resulting in significant
568 * New features in the GDB remote stub, GDBserver
570 ** GDBserver now supports target-assisted range stepping. Currently
571 enabled on x86/x86_64 GNU/Linux targets.
573 ** GDBserver now adds element 'tvar' in the XML in the reply to
574 'qXfer:traceframe-info:read'. It has the id of the collected
575 trace state variables.
577 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
580 * New 'z' formatter for printing and examining memory, this displays the
581 value as hexadecimal zero padded on the left to the size of the type.
583 * GDB can now use Windows x64 unwinding data.
585 * The "set remotebaud" command has been replaced by "set serial baud".
586 Similarly, "show remotebaud" has been replaced by "show serial baud".
587 The "set remotebaud" and "show remotebaud" commands are still available
588 to provide backward compatibility with older versions of GDB.
590 *** Changes in GDB 7.6
592 * Target record has been renamed to record-full.
593 Record/replay is now enabled with the "record full" command.
594 This also affects settings that are associated with full record/replay
595 that have been moved from "set/show record" to "set/show record full":
597 set|show record full insn-number-max
598 set|show record full stop-at-limit
599 set|show record full memory-query
601 * A new record target "record-btrace" has been added. The new target
602 uses hardware support to record the control-flow of a process. It
603 does not support replaying the execution, but it implements the
604 below new commands for investigating the recorded execution log.
605 This new recording method can be enabled using:
609 The "record-btrace" target is only available on Intel Atom processors
610 and requires a Linux kernel 2.6.32 or later.
612 * Two new commands have been added for record/replay to give information
613 about the recorded execution without having to replay the execution.
614 The commands are only supported by "record btrace".
616 record instruction-history prints the execution history at
617 instruction granularity
619 record function-call-history prints the execution history at
622 * New native configurations
624 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
625 FreeBSD/powerpc powerpc*-*-freebsd
626 x86_64/Cygwin x86_64-*-cygwin*
627 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
631 ARM AArch64 aarch64*-*-elf
632 ARM AArch64 GNU/Linux aarch64*-*-linux
633 Lynx 178 PowerPC powerpc-*-lynx*178
634 x86_64/Cygwin x86_64-*-cygwin*
635 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
637 * If the configured location of system.gdbinit file (as given by the
638 --with-system-gdbinit option at configure time) is in the
639 data-directory (as specified by --with-gdb-datadir at configure
640 time) or in one of its subdirectories, then GDB will look for the
641 system-wide init file in the directory specified by the
642 --data-directory command-line option.
644 * New command line options:
646 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
647 other initialization files, unlike -nx which disables all of them.
649 * Removed command line options
651 -epoch This was used by the gdb mode in Epoch, an ancient fork of
654 * The 'ptype' and 'whatis' commands now accept an argument to control
657 * 'info proc' now works on some core files.
661 ** Vectors can be created with gdb.Type.vector.
663 ** Python's atexit.register now works in GDB.
665 ** Types can be pretty-printed via a Python API.
667 ** Python 3 is now supported (in addition to Python 2.4 or later)
669 ** New class gdb.Architecture exposes GDB's internal representation
670 of architecture in the Python API.
672 ** New method Frame.architecture returns the gdb.Architecture object
673 corresponding to the frame's architecture.
675 * New Python-based convenience functions:
677 ** $_memeq(buf1, buf2, length)
678 ** $_streq(str1, str2)
680 ** $_regex(str, regex)
682 * The 'cd' command now defaults to using '~' (the home directory) if not
685 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
686 default for GCC since November 2000.
688 * The command 'forward-search' can now be abbreviated as 'fo'.
690 * The command 'info tracepoints' can now display 'installed on target'
691 or 'not installed on target' for each non-pending location of tracepoint.
693 * New configure options
695 --enable-libmcheck/--disable-libmcheck
696 By default, development versions are built with -lmcheck on hosts
697 that support it, in order to help track memory corruption issues.
698 Release versions, on the other hand, are built without -lmcheck
699 by default. The --enable-libmcheck/--disable-libmcheck configure
700 options allow the user to override that default.
701 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
702 This configure option allows the user to build GDB with
703 libbabeltrace using which GDB can read Common Trace Format data.
705 * New commands (for set/show, see "New options" below)
708 Catch signals. This is similar to "handle", but allows commands and
709 conditions to be attached.
712 List the BFDs known to GDB.
714 python-interactive [command]
716 Start a Python interactive prompt, or evaluate the optional command
717 and print the result of expressions.
720 "py" is a new alias for "python".
722 enable type-printer [name]...
723 disable type-printer [name]...
724 Enable or disable type printers.
728 ** For the Renesas Super-H architecture, the "regs" command has been removed
729 (has been deprecated in GDB 7.5), and "info all-registers" should be used
734 set print type methods (on|off)
735 show print type methods
736 Control whether method declarations are displayed by "ptype".
737 The default is to show them.
739 set print type typedefs (on|off)
740 show print type typedefs
741 Control whether typedef definitions are displayed by "ptype".
742 The default is to show them.
744 set filename-display basename|relative|absolute
745 show filename-display
746 Control the way in which filenames is displayed.
747 The default is "relative", which preserves previous behavior.
749 set trace-buffer-size
750 show trace-buffer-size
751 Request target to change the size of trace buffer.
753 set remote trace-buffer-size-packet auto|on|off
754 show remote trace-buffer-size-packet
755 Control the use of the remote protocol `QTBuffer:size' packet.
759 Control display of debugging messages related to ARM AArch64.
762 set debug coff-pe-read
763 show debug coff-pe-read
764 Control display of debugging messages related to reading of COFF/PE
769 Control display of debugging messages related to Mach-O symbols
772 set debug notification
773 show debug notification
774 Control display of debugging info for async remote notification.
778 ** Command parameter changes are now notified using new async record
779 "=cmd-param-changed".
780 ** Trace frame changes caused by command "tfind" are now notified using
781 new async record "=traceframe-changed".
782 ** The creation, deletion and modification of trace state variables
783 are now notified using new async records "=tsv-created",
784 "=tsv-deleted" and "=tsv-modified".
785 ** The start and stop of process record are now notified using new
786 async record "=record-started" and "=record-stopped".
787 ** Memory changes are now notified using new async record
789 ** The data-disassemble command response will include a "fullname" field
790 containing the absolute file name when source has been requested.
791 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
792 command, to allow pattern filling of memory areas.
793 ** New commands "-catch-load"/"-catch-unload" added for intercepting
794 library load/unload events.
795 ** The response to breakpoint commands and breakpoint async records
796 includes an "installed" field containing a boolean state about each
797 non-pending tracepoint location is whether installed on target or not.
798 ** Output of the "-trace-status" command includes a "trace-file" field
799 containing the name of the trace file being examined. This field is
800 optional, and only present when examining a trace file.
801 ** The "fullname" field is now always present along with the "file" field,
802 even if the file cannot be found by GDB.
804 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
805 You must have the LZMA library available when configuring GDB for this
806 feature to be enabled. For more information, see:
807 http://fedoraproject.org/wiki/Features/MiniDebugInfo
812 Set the size of trace buffer. The remote stub reports support for this
813 packet to gdb's qSupported query.
816 Enable Branch Trace Store (BTS)-based branch tracing for the current
817 thread. The remote stub reports support for this packet to gdb's
821 Disable branch tracing for the current thread. The remote stub reports
822 support for this packet to gdb's qSupported query.
825 Read the traced branches for the current thread. The remote stub
826 reports support for this packet to gdb's qSupported query.
828 *** Changes in GDB 7.5
830 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
831 for more x32 ABI info.
833 * GDB now supports access to MIPS DSP registers on Linux targets.
835 * GDB now supports debugging microMIPS binaries.
837 * The "info os" command on GNU/Linux can now display information on
838 several new classes of objects managed by the operating system:
839 "info os procgroups" lists process groups
840 "info os files" lists file descriptors
841 "info os sockets" lists internet-domain sockets
842 "info os shm" lists shared-memory regions
843 "info os semaphores" lists semaphores
844 "info os msg" lists message queues
845 "info os modules" lists loaded kernel modules
847 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
848 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
849 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
850 options and inspect the probe arguments using the new $_probe_arg family
851 of convenience variables. You can obtain more information about SystemTap
852 in <http://sourceware.org/systemtap/>.
854 * GDB now supports reversible debugging on ARM, it allows you to
855 debug basic ARM and THUMB instructions, and provides
856 record/replay support.
858 * The option "symbol-reloading" has been deleted as it is no longer used.
862 ** GDB commands implemented in Python can now be put in command class
865 ** The "maint set python print-stack on|off" is now deleted.
867 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
868 apply "flag enum"-style pretty-printing to any enum.
870 ** gdb.lookup_symbol can now work when there is no current frame.
872 ** gdb.Symbol now has a 'line' attribute, holding the line number in
873 the source at which the symbol was defined.
875 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
876 method 'value'. The former indicates whether the symbol needs a
877 frame in order to compute its value, and the latter computes the
880 ** A new method 'referenced_value' on gdb.Value objects which can
881 dereference pointer as well as C++ reference values.
883 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
884 which return the global and static blocks (as gdb.Block objects),
885 of the underlying symbol table, respectively.
887 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
888 object associated with a PC value.
890 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
891 of the address range occupied by code for the current source line.
893 * Go language support.
894 GDB now supports debugging programs written in the Go programming
897 * GDBserver now supports stdio connections.
898 E.g. (gdb) target remote | ssh myhost gdbserver - hello
900 * The binary "gdbtui" can no longer be built or installed.
901 Use "gdb -tui" instead.
903 * GDB will now print "flag" enums specially. A flag enum is one where
904 all the enumerator values have no bits in common when pairwise
905 "and"ed. When printing a value whose type is a flag enum, GDB will
906 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
907 (gdb) print (enum E) 3
910 * The filename part of a linespec will now match trailing components
911 of a source file name. For example, "break gcc/expr.c:1000" will
912 now set a breakpoint in build/gcc/expr.c, but not
915 * The "info proc" and "generate-core-file" commands will now also
916 work on remote targets connected to GDBserver on Linux.
918 * The command "info catch" has been removed. It has been disabled
921 * The "catch exception" and "catch assert" commands now accept
922 a condition at the end of the command, much like the "break"
923 command does. For instance:
925 (gdb) catch exception Constraint_Error if Barrier = True
927 Previously, it was possible to add a condition to such catchpoints,
928 but it had to be done as a second step, after the catchpoint had been
929 created, using the "condition" command.
931 * The "info static-tracepoint-marker" command will now also work on
932 native Linux targets with in-process agent.
934 * GDB can now set breakpoints on inlined functions.
936 * The .gdb_index section has been updated to include symbols for
937 inlined functions. GDB will ignore older .gdb_index sections by
938 default, which could cause symbol files to be loaded more slowly
939 until their .gdb_index sections can be recreated. The new command
940 "set use-deprecated-index-sections on" will cause GDB to use any older
941 .gdb_index sections it finds. This will restore performance, but the
942 ability to set breakpoints on inlined functions will be lost in symbol
943 files with older .gdb_index sections.
945 The .gdb_index section has also been updated to record more information
946 about each symbol. This speeds up the "info variables", "info functions"
947 and "info types" commands when used with programs having the .gdb_index
948 section, as well as speeding up debugging with shared libraries using
949 the .gdb_index section.
951 * Ada support for GDB/MI Variable Objects has been added.
953 * GDB can now support 'breakpoint always-inserted mode' in 'record'
958 ** New command -info-os is the MI equivalent of "info os".
960 ** Output logs ("set logging" and related) now include MI output.
964 ** "set use-deprecated-index-sections on|off"
965 "show use-deprecated-index-sections on|off"
966 Controls the use of deprecated .gdb_index sections.
968 ** "catch load" and "catch unload" can be used to stop when a shared
969 library is loaded or unloaded, respectively.
971 ** "enable count" can be used to auto-disable a breakpoint after
974 ** "info vtbl" can be used to show the virtual method tables for
975 C++ and Java objects.
977 ** "explore" and its sub commands "explore value" and "explore type"
978 can be used to recursively explore values and types of
979 expressions. These commands are available only if GDB is
980 configured with '--with-python'.
982 ** "info auto-load" shows status of all kinds of auto-loaded files,
983 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
984 sequences of commands files, "info auto-load python-scripts"
985 shows status of auto-loading Python script files,
986 "info auto-load local-gdbinit" shows status of loading init file
987 (.gdbinit) from current directory and "info auto-load libthread-db" shows
988 status of inferior specific thread debugging shared library loading.
990 ** "info auto-load-scripts", "set auto-load-scripts on|off"
991 and "show auto-load-scripts" commands have been deprecated, use their
992 "info auto-load python-scripts", "set auto-load python-scripts on|off"
993 and "show auto-load python-scripts" counterparts instead.
995 ** "dprintf location,format,args..." creates a dynamic printf, which
996 is basically a breakpoint that does a printf and immediately
997 resumes your program's execution, so it is like a printf that you
998 can insert dynamically at runtime instead of at compiletime.
1000 ** "set print symbol"
1002 Controls whether GDB attempts to display the symbol, if any,
1003 corresponding to addresses it prints. This defaults to "on", but
1004 you can set it to "off" to restore GDB's previous behavior.
1006 * Deprecated commands
1008 ** For the Renesas Super-H architecture, the "regs" command has been
1009 deprecated, and "info all-registers" should be used instead.
1013 Renesas RL78 rl78-*-elf
1014 HP OpenVMS ia64 ia64-hp-openvms*
1016 * GDBserver supports evaluation of breakpoint conditions. When
1017 support is advertised by GDBserver, GDB may be told to send the
1018 breakpoint conditions in bytecode form to GDBserver. GDBserver
1019 will only report the breakpoint trigger to GDB when its condition
1024 set mips compression
1025 show mips compression
1026 Select the compressed ISA encoding used in functions that have no symbol
1027 information available. The encoding can be set to either of:
1030 and is updated automatically from ELF file flags if available.
1032 set breakpoint condition-evaluation
1033 show breakpoint condition-evaluation
1034 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1035 GDBserver ("target"). Default option "auto" chooses the most efficient
1037 This option can improve debugger efficiency depending on the speed of the
1041 Disable auto-loading globally.
1044 Show auto-loading setting of all kinds of auto-loaded files.
1046 set auto-load gdb-scripts on|off
1047 show auto-load gdb-scripts
1048 Control auto-loading of GDB canned sequences of commands files.
1050 set auto-load python-scripts on|off
1051 show auto-load python-scripts
1052 Control auto-loading of Python script files.
1054 set auto-load local-gdbinit on|off
1055 show auto-load local-gdbinit
1056 Control loading of init file (.gdbinit) from current directory.
1058 set auto-load libthread-db on|off
1059 show auto-load libthread-db
1060 Control auto-loading of inferior specific thread debugging shared library.
1062 set auto-load scripts-directory <dir1>[:<dir2>...]
1063 show auto-load scripts-directory
1064 Set a list of directories from which to load auto-loaded scripts.
1065 Automatically loaded Python scripts and GDB scripts are located in one
1066 of the directories listed by this option.
1067 The delimiter (':' above) may differ according to the host platform.
1069 set auto-load safe-path <dir1>[:<dir2>...]
1070 show auto-load safe-path
1071 Set a list of directories from which it is safe to auto-load files.
1072 The delimiter (':' above) may differ according to the host platform.
1074 set debug auto-load on|off
1075 show debug auto-load
1076 Control display of debugging info for auto-loading the files above.
1078 set dprintf-style gdb|call|agent
1080 Control the way in which a dynamic printf is performed; "gdb"
1081 requests a GDB printf command, while "call" causes dprintf to call a
1082 function in the inferior. "agent" requests that the target agent
1083 (such as GDBserver) do the printing.
1085 set dprintf-function <expr>
1086 show dprintf-function
1087 set dprintf-channel <expr>
1088 show dprintf-channel
1089 Set the function and optional first argument to the call when using
1090 the "call" style of dynamic printf.
1092 set disconnected-dprintf on|off
1093 show disconnected-dprintf
1094 Control whether agent-style dynamic printfs continue to be in effect
1095 after GDB disconnects.
1097 * New configure options
1099 --with-auto-load-dir
1100 Configure default value for the 'set auto-load scripts-directory'
1101 setting above. It defaults to '$debugdir:$datadir/auto-load',
1102 $debugdir representing global debugging info directories (available
1103 via 'show debug-file-directory') and $datadir representing GDB's data
1104 directory (available via 'show data-directory').
1106 --with-auto-load-safe-path
1107 Configure default value for the 'set auto-load safe-path' setting
1108 above. It defaults to the --with-auto-load-dir setting.
1110 --without-auto-load-safe-path
1111 Set 'set auto-load safe-path' to '/', effectively disabling this
1114 * New remote packets
1116 z0/z1 conditional breakpoints extension
1118 The z0/z1 breakpoint insertion packets have been extended to carry
1119 a list of conditional expressions over to the remote stub depending on the
1120 condition evaluation mode. The use of this extension can be controlled
1121 via the "set remote conditional-breakpoints-packet" command.
1125 Specify the signals which the remote stub may pass to the debugged
1126 program without GDB involvement.
1128 * New command line options
1130 --init-command=FILE, -ix Like --command, -x but execute it
1131 before loading inferior.
1132 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1133 execute it before loading inferior.
1135 *** Changes in GDB 7.4
1137 * GDB now handles ambiguous linespecs more consistently; the existing
1138 FILE:LINE support has been expanded to other types of linespecs. A
1139 breakpoint will now be set on all matching locations in all
1140 inferiors, and locations will be added or removed according to
1143 * GDB now allows you to skip uninteresting functions and files when
1144 stepping with the "skip function" and "skip file" commands.
1146 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1147 and "show remote hardware-watchpoint-length-limit". These allows to
1148 set or show the maximum length limit (in bytes) of a remote
1149 target hardware watchpoint.
1151 This allows e.g. to use "unlimited" hardware watchpoints with the
1152 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1153 watchpoints are slower than real hardware watchpoints but are
1154 significantly faster than gdb software watchpoints.
1158 ** The register_pretty_printer function in module gdb.printing now takes
1159 an optional `replace' argument. If True, the new printer replaces any
1162 ** The "maint set python print-stack on|off" command has been
1163 deprecated and will be deleted in GDB 7.5.
1164 A new command: "set python print-stack none|full|message" has
1165 replaced it. Additionally, the default for "print-stack" is
1166 now "message", which just prints the error message without
1169 ** A prompt substitution hook (prompt_hook) is now available to the
1172 ** A new Python module, gdb.prompt has been added to the GDB Python
1173 modules library. This module provides functionality for
1174 escape sequences in prompts (used by set/show
1175 extended-prompt). These escape sequences are replaced by their
1176 corresponding value.
1178 ** Python commands and convenience-functions located in
1179 'data-directory'/python/gdb/command and
1180 'data-directory'/python/gdb/function are now automatically loaded
1183 ** Blocks now provide four new attributes. global_block and
1184 static_block will return the global and static blocks
1185 respectively. is_static and is_global are boolean attributes
1186 that indicate if the block is one of those two types.
1188 ** Symbols now provide the "type" attribute, the type of the symbol.
1190 ** The "gdb.breakpoint" function has been deprecated in favor of
1193 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1194 of a function. This class is based on the "finish" command
1195 available in the CLI.
1197 ** Type objects for struct and union types now allow access to
1198 the fields using standard Python dictionary (mapping) methods.
1199 For example, "some_type['myfield']" now works, as does
1200 "some_type.items()".
1202 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1205 ** A new function, "deep_items" has been added to the gdb.types
1206 module in the GDB Python modules library. This function returns
1207 an iterator over the fields of a struct or union type. Unlike
1208 the standard Python "iteritems" method, it will recursively traverse
1209 any anonymous fields.
1213 ** "*stopped" events can report several new "reason"s, such as
1216 ** Breakpoint changes are now notified using new async records, like
1217 "=breakpoint-modified".
1219 ** New command -ada-task-info.
1221 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1222 $sdir specifies the default system locations of shared libraries.
1223 $pdir specifies the directory where the libpthread used by the application
1226 GDB no longer looks in $sdir and $pdir after it has searched the directories
1227 mentioned in libthread-db-search-path. If you want to search those
1228 directories, they must be specified in libthread-db-search-path.
1229 The default value of libthread-db-search-path on GNU/Linux and Solaris
1230 systems is now "$sdir:$pdir".
1232 $pdir is not supported by gdbserver, it is currently ignored.
1233 $sdir is supported by gdbserver.
1235 * New configure option --with-iconv-bin.
1236 When using the internationalization support like the one in the GNU C
1237 library, GDB will invoke the "iconv" program to get a list of supported
1238 character sets. If this program lives in a non-standard location, one can
1239 use this option to specify where to find it.
1241 * When natively debugging programs on PowerPC BookE processors running
1242 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1243 watchpoints, which specify a mask in addition to an address to watch.
1244 The mask specifies that some bits of an address (the bits which are
1245 reset in the mask) should be ignored when matching the address accessed
1246 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1247 section in the user manual for more details.
1249 * The new option --once causes GDBserver to stop listening for connections once
1250 the first connection is made. The listening port used by GDBserver will
1251 become available after that.
1253 * New commands "info macros" and "alias" have been added.
1255 * New function parameters suffix @entry specifies value of function parameter
1256 at the time the function got called. Entry values are available only since
1262 "!" is now an alias of the "shell" command.
1263 Note that no space is needed between "!" and SHELL COMMAND.
1267 watch EXPRESSION mask MASK_VALUE
1268 The watch command now supports the mask argument which allows creation
1269 of masked watchpoints, if the current architecture supports this feature.
1271 info auto-load-scripts [REGEXP]
1272 This command was formerly named "maintenance print section-scripts".
1273 It is now generally useful and is no longer a maintenance-only command.
1275 info macro [-all] [--] MACRO
1276 The info macro command has new options `-all' and `--'. The first for
1277 printing all definitions of a macro. The second for explicitly specifying
1278 the end of arguments and the beginning of the macro name in case the macro
1279 name starts with a hyphen.
1281 collect[/s] EXPRESSIONS
1282 The tracepoint collect command now takes an optional modifier "/s"
1283 that directs it to dereference pointer-to-character types and
1284 collect the bytes of memory up to a zero byte. The behavior is
1285 similar to what you see when you use the regular print command on a
1286 string. An optional integer following the "/s" sets a bound on the
1287 number of bytes that will be collected.
1290 The trace start command now interprets any supplied arguments as a
1291 note to be recorded with the trace run, with an effect similar to
1292 setting the variable trace-notes.
1295 The trace stop command now interprets any arguments as a note to be
1296 mentioned along with the tstatus report that the trace was stopped
1297 with a command. The effect is similar to setting the variable
1300 * Tracepoints can now be enabled and disabled at any time after a trace
1301 experiment has been started using the standard "enable" and "disable"
1302 commands. It is now possible to start a trace experiment with no enabled
1303 tracepoints; GDB will display a warning, but will allow the experiment to
1304 begin, assuming that tracepoints will be enabled as needed while the trace
1307 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1308 locations with 4-byte instructions, when they were previously
1309 limited to locations with instructions of 5 bytes or longer.
1313 set debug dwarf2-read
1314 show debug dwarf2-read
1315 Turns on or off display of debugging messages related to reading
1316 DWARF debug info. The default is off.
1318 set debug symtab-create
1319 show debug symtab-create
1320 Turns on or off display of debugging messages related to symbol table
1321 creation. The default is off.
1324 show extended-prompt
1325 Set the GDB prompt, and allow escape sequences to be inserted to
1326 display miscellaneous information (see 'help set extended-prompt'
1327 for the list of sequences). This prompt (and any information
1328 accessed through the escape sequences) is updated every time the
1329 prompt is displayed.
1331 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1332 show print entry-values
1333 Set printing of frame argument values at function entry. In some cases
1334 GDB can determine the value of function argument which was passed by the
1335 function caller, even if the value was modified inside the called function.
1337 set debug entry-values
1338 show debug entry-values
1339 Control display of debugging info for determining frame argument values at
1340 function entry and virtual tail call frames.
1342 set basenames-may-differ
1343 show basenames-may-differ
1344 Set whether a source file may have multiple base names.
1345 (A "base name" is the name of a file with the directory part removed.
1346 Example: The base name of "/home/user/hello.c" is "hello.c".)
1347 If set, GDB will canonicalize file names (e.g., expand symlinks)
1348 before comparing them. Canonicalization is an expensive operation,
1349 but it allows the same file be known by more than one base name.
1350 If not set (the default), all source files are assumed to have just
1351 one base name, and gdb will do file name comparisons more efficiently.
1357 Set a user name and notes for the current and any future trace runs.
1358 This is useful for long-running and/or disconnected traces, to
1359 inform others (or yourself) as to who is running the trace, supply
1360 contact information, or otherwise explain what is going on.
1362 set trace-stop-notes
1363 show trace-stop-notes
1364 Set a note attached to the trace run, that is displayed when the
1365 trace has been stopped by a tstop command. This is useful for
1366 instance as an explanation, if you are stopping a trace run that was
1367 started by someone else.
1369 * New remote packets
1373 Dynamically enable a tracepoint in a started trace experiment.
1377 Dynamically disable a tracepoint in a started trace experiment.
1381 Set the user and notes of the trace run.
1385 Query the current status of a tracepoint.
1389 Query the minimum length of instruction at which a fast tracepoint may
1392 * Dcache size (number of lines) and line-size are now runtime-configurable
1393 via "set dcache line" and "set dcache line-size" commands.
1397 Texas Instruments TMS320C6x tic6x-*-*
1401 Renesas RL78 rl78-*-elf
1403 *** Changes in GDB 7.3.1
1405 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1407 *** Changes in GDB 7.3
1409 * GDB has a new command: "thread find [REGEXP]".
1410 It finds the thread id whose name, target id, or thread extra info
1411 matches the given regular expression.
1413 * The "catch syscall" command now works on mips*-linux* targets.
1415 * The -data-disassemble MI command now supports modes 2 and 3 for
1416 dumping the instruction opcodes.
1418 * New command line options
1420 -data-directory DIR Specify DIR as the "data-directory".
1421 This is mostly for testing purposes.
1423 * The "maint set python auto-load on|off" command has been renamed to
1424 "set auto-load-scripts on|off".
1426 * GDB has a new command: "set directories".
1427 It is like the "dir" command except that it replaces the
1428 source path list instead of augmenting it.
1430 * GDB now understands thread names.
1432 On GNU/Linux, "info threads" will display the thread name as set by
1433 prctl or pthread_setname_np.
1435 There is also a new command, "thread name", which can be used to
1436 assign a name internally for GDB to display.
1439 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1440 has been integrated into GDB.
1444 ** The function gdb.Write now accepts an optional keyword 'stream'.
1445 This keyword, when provided, will direct the output to either
1446 stdout, stderr, or GDB's logging output.
1448 ** Parameters can now be be sub-classed in Python, and in particular
1449 you may implement the get_set_doc and get_show_doc functions.
1450 This improves how Parameter set/show documentation is processed
1451 and allows for more dynamic content.
1453 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1454 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1455 have an is_valid method.
1457 ** Breakpoints can now be sub-classed in Python, and in particular
1458 you may implement a 'stop' function that is executed each time
1459 the inferior reaches that breakpoint.
1461 ** New function gdb.lookup_global_symbol looks up a global symbol.
1463 ** GDB values in Python are now callable if the value represents a
1464 function. For example, if 'some_value' represents a function that
1465 takes two integer parameters and returns a value, you can call
1466 that function like so:
1468 result = some_value (10,20)
1470 ** Module gdb.types has been added.
1471 It contains a collection of utilities for working with gdb.Types objects:
1472 get_basic_type, has_field, make_enum_dict.
1474 ** Module gdb.printing has been added.
1475 It contains utilities for writing and registering pretty-printers.
1476 New classes: PrettyPrinter, SubPrettyPrinter,
1477 RegexpCollectionPrettyPrinter.
1478 New function: register_pretty_printer.
1480 ** New commands "info pretty-printers", "enable pretty-printer" and
1481 "disable pretty-printer" have been added.
1483 ** gdb.parameter("directories") is now available.
1485 ** New function gdb.newest_frame returns the newest frame in the
1488 ** The gdb.InferiorThread class has a new "name" attribute. This
1489 holds the thread's name.
1491 ** Python Support for Inferior events.
1492 Python scripts can add observers to be notified of events
1493 occurring in the process being debugged.
1494 The following events are currently supported:
1495 - gdb.events.cont Continue event.
1496 - gdb.events.exited Inferior exited event.
1497 - gdb.events.stop Signal received, and Breakpoint hit events.
1501 ** GDB now puts template parameters in scope when debugging in an
1502 instantiation. For example, if you have:
1504 template<int X> int func (void) { return X; }
1506 then if you step into func<5>, "print X" will show "5". This
1507 feature requires proper debuginfo support from the compiler; it
1508 was added to GCC 4.5.
1510 ** The motion commands "next", "finish", "until", and "advance" now
1511 work better when exceptions are thrown. In particular, GDB will
1512 no longer lose control of the inferior; instead, the GDB will
1513 stop the inferior at the point at which the exception is caught.
1514 This functionality requires a change in the exception handling
1515 code that was introduced in GCC 4.5.
1517 * GDB now follows GCC's rules on accessing volatile objects when
1518 reading or writing target state during expression evaluation.
1519 One notable difference to prior behavior is that "print x = 0"
1520 no longer generates a read of x; the value of the assignment is
1521 now always taken directly from the value being assigned.
1523 * GDB now has some support for using labels in the program's source in
1524 linespecs. For instance, you can use "advance label" to continue
1525 execution to a label.
1527 * GDB now has support for reading and writing a new .gdb_index
1528 section. This section holds a fast index of DWARF debugging
1529 information and can be used to greatly speed up GDB startup and
1530 operation. See the documentation for `save gdb-index' for details.
1532 * The "watch" command now accepts an optional "-location" argument.
1533 When used, this causes GDB to watch the memory referred to by the
1534 expression. Such a watchpoint is never deleted due to it going out
1537 * GDB now supports thread debugging of core dumps on GNU/Linux.
1539 GDB now activates thread debugging using the libthread_db library
1540 when debugging GNU/Linux core dumps, similarly to when debugging
1541 live processes. As a result, when debugging a core dump file, GDB
1542 is now able to display pthread_t ids of threads. For example, "info
1543 threads" shows the same output as when debugging the process when it
1544 was live. In earlier releases, you'd see something like this:
1547 * 1 LWP 6780 main () at main.c:10
1549 While now you see this:
1552 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1554 It is also now possible to inspect TLS variables when debugging core
1557 When debugging a core dump generated on a machine other than the one
1558 used to run GDB, you may need to point GDB at the correct
1559 libthread_db library with the "set libthread-db-search-path"
1560 command. See the user manual for more details on this command.
1562 * When natively debugging programs on PowerPC BookE processors running
1563 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1564 which stop execution of the inferior whenever it executes an instruction
1565 at any address within the specified range. See the "PowerPC Embedded"
1566 section in the user manual for more details.
1568 * New features in the GDB remote stub, GDBserver
1570 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1571 and i686 LynxOS (version 5.x).
1573 ** GDBserver is now supported on Blackfin Linux.
1575 * New native configurations
1577 ia64 HP-UX ia64-*-hpux*
1581 Analog Devices, Inc. Blackfin Processor bfin-*
1583 * Ada task switching is now supported on sparc-elf targets when
1584 debugging a program using the Ravenscar Profile. For more information,
1585 see the "Tasking Support when using the Ravenscar Profile" section
1586 in the GDB user manual.
1588 * Guile support was removed.
1590 * New features in the GNU simulator
1592 ** The --map-info flag lists all known core mappings.
1594 ** CFI flashes may be simulated via the "cfi" device.
1596 *** Changes in GDB 7.2
1598 * Shared library support for remote targets by default
1600 When GDB is configured for a generic, non-OS specific target, like
1601 for example, --target=arm-eabi or one of the many *-*-elf targets,
1602 GDB now queries remote stubs for loaded shared libraries using the
1603 `qXfer:libraries:read' packet. Previously, shared library support
1604 was always disabled for such configurations.
1608 ** Argument Dependent Lookup (ADL)
1610 In C++ ADL lookup directs function search to the namespaces of its
1611 arguments even if the namespace has not been imported.
1621 Here the compiler will search for `foo' in the namespace of 'b'
1622 and find A::foo. GDB now supports this. This construct is commonly
1623 used in the Standard Template Library for operators.
1625 ** Improved User Defined Operator Support
1627 In addition to member operators, GDB now supports lookup of operators
1628 defined in a namespace and imported with a `using' directive, operators
1629 defined in the global scope, operators imported implicitly from an
1630 anonymous namespace, and the ADL operators mentioned in the previous
1632 GDB now also supports proper overload resolution for all the previously
1633 mentioned flavors of operators.
1635 ** static const class members
1637 Printing of static const class members that are initialized in the
1638 class definition has been fixed.
1640 * Windows Thread Information Block access.
1642 On Windows targets, GDB now supports displaying the Windows Thread
1643 Information Block (TIB) structure. This structure is visible either
1644 by using the new command `info w32 thread-information-block' or, by
1645 dereferencing the new convenience variable named `$_tlb', a
1646 thread-specific pointer to the TIB. This feature is also supported
1647 when remote debugging using GDBserver.
1649 * Static tracepoints
1651 Static tracepoints are calls in the user program into a tracing
1652 library. One such library is a port of the LTTng kernel tracer to
1653 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1654 When debugging with GDBserver, GDB now supports combining the GDB
1655 tracepoint machinery with such libraries. For example: the user can
1656 use GDB to probe a static tracepoint marker (a call from the user
1657 program into the tracing library) with the new "strace" command (see
1658 "New commands" below). This creates a "static tracepoint" in the
1659 breakpoint list, that can be manipulated with the same feature set
1660 as fast and regular tracepoints. E.g., collect registers, local and
1661 global variables, collect trace state variables, and define
1662 tracepoint conditions. In addition, the user can collect extra
1663 static tracepoint marker specific data, by collecting the new
1664 $_sdata internal variable. When analyzing the trace buffer, you can
1665 inspect $_sdata like any other variable available to GDB. For more
1666 information, see the "Tracepoints" chapter in GDB user manual. New
1667 remote packets have been defined to support static tracepoints, see
1668 the "New remote packets" section below.
1670 * Better reconstruction of tracepoints after disconnected tracing
1672 GDB will attempt to download the original source form of tracepoint
1673 definitions when starting a trace run, and then will upload these
1674 upon reconnection to the target, resulting in a more accurate
1675 reconstruction of the tracepoints that are in use on the target.
1679 You can now exercise direct control over the ways that GDB can
1680 affect your program. For instance, you can disallow the setting of
1681 breakpoints, so that the program can run continuously (assuming
1682 non-stop mode). In addition, the "observer" variable is available
1683 to switch all of the different controls; in observer mode, GDB
1684 cannot affect the target's behavior at all, which is useful for
1685 tasks like diagnosing live systems in the field.
1687 * The new convenience variable $_thread holds the number of the
1690 * New remote packets
1694 Return the address of the Windows Thread Information Block of a given thread.
1698 In response to several of the tracepoint packets, the target may now
1699 also respond with a number of intermediate `qRelocInsn' request
1700 packets before the final result packet, to have GDB handle
1701 relocating an instruction to execute at a different address. This
1702 is particularly useful for stubs that support fast tracepoints. GDB
1703 reports support for this feature in the qSupported packet.
1707 List static tracepoint markers in the target program.
1711 List static tracepoint markers at a given address in the target
1714 qXfer:statictrace:read
1716 Read the static trace data collected (by a `collect $_sdata'
1717 tracepoint action). The remote stub reports support for this packet
1718 to gdb's qSupported query.
1722 Send the current settings of GDB's permission flags.
1726 Send part of the source (textual) form of a tracepoint definition,
1727 which includes location, conditional, and action list.
1729 * The source command now accepts a -s option to force searching for the
1730 script in the source search path even if the script name specifies
1733 * New features in the GDB remote stub, GDBserver
1735 - GDBserver now support tracepoints (including fast tracepoints, and
1736 static tracepoints). The feature is currently supported by the
1737 i386-linux and amd64-linux builds. See the "Tracepoints support
1738 in gdbserver" section in the manual for more information.
1740 GDBserver JIT compiles the tracepoint's conditional agent
1741 expression bytecode into native code whenever possible for low
1742 overhead dynamic tracepoints conditionals. For such tracepoints,
1743 an expression that examines program state is evaluated when the
1744 tracepoint is reached, in order to determine whether to capture
1745 trace data. If the condition is simple and false, processing the
1746 tracepoint finishes very quickly and no data is gathered.
1748 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1749 for static tracepoints support.
1751 - GDBserver now supports x86_64 Windows 64-bit debugging.
1753 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1754 it understands register description.
1756 * The --batch flag now disables pagination and queries.
1758 * X86 general purpose registers
1760 GDB now supports reading/writing byte, word and double-word x86
1761 general purpose registers directly. This means you can use, say,
1762 $ah or $ax to refer, respectively, to the byte register AH and
1763 16-bit word register AX that are actually portions of the 32-bit
1764 register EAX or 64-bit register RAX.
1766 * The `commands' command now accepts a range of breakpoints to modify.
1767 A plain `commands' following a command that creates multiple
1768 breakpoints affects all the breakpoints set by that command. This
1769 applies to breakpoints set by `rbreak', and also applies when a
1770 single `break' command creates multiple breakpoints (e.g.,
1771 breakpoints on overloaded c++ functions).
1773 * The `rbreak' command now accepts a filename specification as part of
1774 its argument, limiting the functions selected by the regex to those
1775 in the specified file.
1777 * Support for remote debugging Windows and SymbianOS shared libraries
1778 from Unix hosts has been improved. Non Windows GDB builds now can
1779 understand target reported file names that follow MS-DOS based file
1780 system semantics, such as file names that include drive letters and
1781 use the backslash character as directory separator. This makes it
1782 possible to transparently use the "set sysroot" and "set
1783 solib-search-path" on Unix hosts to point as host copies of the
1784 target's shared libraries. See the new command "set
1785 target-file-system-kind" described below, and the "Commands to
1786 specify files" section in the user manual for more information.
1790 eval template, expressions...
1791 Convert the values of one or more expressions under the control
1792 of the string template to a command line, and call it.
1794 set target-file-system-kind unix|dos-based|auto
1795 show target-file-system-kind
1796 Set or show the assumed file system kind for target reported file
1799 save breakpoints <filename>
1800 Save all current breakpoint definitions to a file suitable for use
1801 in a later debugging session. To read the saved breakpoint
1802 definitions, use the `source' command.
1804 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1807 info static-tracepoint-markers
1808 Display information about static tracepoint markers in the target.
1810 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1811 Define a static tracepoint by probing a marker at the given
1812 function, line, address, or marker ID.
1816 Enable and disable observer mode.
1818 set may-write-registers on|off
1819 set may-write-memory on|off
1820 set may-insert-breakpoints on|off
1821 set may-insert-tracepoints on|off
1822 set may-insert-fast-tracepoints on|off
1823 set may-interrupt on|off
1824 Set individual permissions for GDB effects on the target. Note that
1825 some of these settings can have undesirable or surprising
1826 consequences, particularly when changed in the middle of a session.
1827 For instance, disabling the writing of memory can prevent
1828 breakpoints from being inserted, cause single-stepping to fail, or
1829 even crash your program, if you disable after breakpoints have been
1830 inserted. However, GDB should not crash.
1832 set record memory-query on|off
1833 show record memory-query
1834 Control whether to stop the inferior if memory changes caused
1835 by an instruction cannot be recorded.
1840 The disassemble command now supports "start,+length" form of two arguments.
1844 ** GDB now provides a new directory location, called the python directory,
1845 where Python scripts written for GDB can be installed. The location
1846 of that directory is <data-directory>/python, where <data-directory>
1847 is the GDB data directory. For more details, see section `Scripting
1848 GDB using Python' in the manual.
1850 ** The GDB Python API now has access to breakpoints, symbols, symbol
1851 tables, program spaces, inferiors, threads and frame's code blocks.
1852 Additionally, GDB Parameters can now be created from the API, and
1853 manipulated via set/show in the CLI.
1855 ** New functions gdb.target_charset, gdb.target_wide_charset,
1856 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1858 ** New exception gdb.GdbError.
1860 ** Pretty-printers are now also looked up in the current program space.
1862 ** Pretty-printers can now be individually enabled and disabled.
1864 ** GDB now looks for names of Python scripts to auto-load in a
1865 special section named `.debug_gdb_scripts', in addition to looking
1866 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1868 * Tracepoint actions were unified with breakpoint commands. In particular,
1869 there are no longer differences in "info break" output for breakpoints and
1870 tracepoints and the "commands" command can be used for both tracepoints and
1871 regular breakpoints.
1875 ARM Symbian arm*-*-symbianelf*
1877 * D language support.
1878 GDB now supports debugging programs written in the D programming
1881 * GDB now supports the extended ptrace interface for PowerPC which is
1882 available since Linux kernel version 2.6.34. This automatically enables
1883 any hardware breakpoints and additional hardware watchpoints available in
1884 the processor. The old ptrace interface exposes just one hardware
1885 watchpoint and no hardware breakpoints.
1887 * GDB is now able to use the Data Value Compare (DVC) register available on
1888 embedded PowerPC processors to implement in hardware simple watchpoint
1889 conditions of the form:
1891 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1893 This works in native GDB running on Linux kernels with the extended ptrace
1894 interface mentioned above.
1896 *** Changes in GDB 7.1
1900 ** Namespace Support
1902 GDB now supports importing of namespaces in C++. This enables the
1903 user to inspect variables from imported namespaces. Support for
1904 namepace aliasing has also been added. So, if a namespace is
1905 aliased in the current scope (e.g. namepace C=A; ) the user can
1906 print variables using the alias (e.g. (gdb) print C::x).
1910 All known bugs relating to the printing of virtual base class were
1911 fixed. It is now possible to call overloaded static methods using a
1916 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1917 and reinterpret_cast<> are now handled by the C++ expression parser.
1921 Xilinx MicroBlaze microblaze-*-*
1926 Xilinx MicroBlaze microblaze
1929 * Multi-program debugging.
1931 GDB now has support for multi-program (a.k.a. multi-executable or
1932 multi-exec) debugging. This allows for debugging multiple inferiors
1933 simultaneously each running a different program under the same GDB
1934 session. See "Debugging Multiple Inferiors and Programs" in the
1935 manual for more information. This implied some user visible changes
1936 in the multi-inferior support. For example, "info inferiors" now
1937 lists inferiors that are not running yet or that have exited
1938 already. See also "New commands" and "New options" below.
1940 * New tracing features
1942 GDB's tracepoint facility now includes several new features:
1944 ** Trace state variables
1946 GDB tracepoints now include support for trace state variables, which
1947 are variables managed by the target agent during a tracing
1948 experiment. They are useful for tracepoints that trigger each
1949 other, so for instance one tracepoint can count hits in a variable,
1950 and then a second tracepoint has a condition that is true when the
1951 count reaches a particular value. Trace state variables share the
1952 $-syntax of GDB convenience variables, and can appear in both
1953 tracepoint actions and condition expressions. Use the "tvariable"
1954 command to create, and "info tvariables" to view; see "Trace State
1955 Variables" in the manual for more detail.
1959 GDB now includes an option for defining fast tracepoints, which
1960 targets may implement more efficiently, such as by installing a jump
1961 into the target agent rather than a trap instruction. The resulting
1962 speedup can be by two orders of magnitude or more, although the
1963 tradeoff is that some program locations on some target architectures
1964 might not allow fast tracepoint installation, for instance if the
1965 instruction to be replaced is shorter than the jump. To request a
1966 fast tracepoint, use the "ftrace" command, with syntax identical to
1967 the regular trace command.
1969 ** Disconnected tracing
1971 It is now possible to detach GDB from the target while it is running
1972 a trace experiment, then reconnect later to see how the experiment
1973 is going. In addition, a new variable disconnected-tracing lets you
1974 tell the target agent whether to continue running a trace if the
1975 connection is lost unexpectedly.
1979 GDB now has the ability to save the trace buffer into a file, and
1980 then use that file as a target, similarly to you can do with
1981 corefiles. You can select trace frames, print data that was
1982 collected in them, and use tstatus to display the state of the
1983 tracing run at the moment that it was saved. To create a trace
1984 file, use "tsave <filename>", and to use it, do "target tfile
1987 ** Circular trace buffer
1989 You can ask the target agent to handle the trace buffer as a
1990 circular buffer, discarding the oldest trace frames to make room for
1991 newer ones, by setting circular-trace-buffer to on. This feature may
1992 not be available for all target agents.
1997 The disassemble command, when invoked with two arguments, now requires
1998 the arguments to be comma-separated.
2001 The info variables command now displays variable definitions. Files
2002 which only declare a variable are not shown.
2005 The source command is now capable of sourcing Python scripts.
2006 This feature is dependent on the debugger being build with Python
2009 Related to this enhancement is also the introduction of a new command
2010 "set script-extension" (see below).
2012 * New commands (for set/show, see "New options" below)
2014 record save [<FILENAME>]
2015 Save a file (in core file format) containing the process record
2016 execution log for replay debugging at a later time.
2018 record restore <FILENAME>
2019 Restore the process record execution log that was saved at an
2020 earlier time, for replay debugging.
2022 add-inferior [-copies <N>] [-exec <FILENAME>]
2025 clone-inferior [-copies <N>] [ID]
2026 Make a new inferior ready to execute the same program another
2027 inferior has loaded.
2032 maint info program-spaces
2033 List the program spaces loaded into GDB.
2035 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2036 show remote interrupt-sequence
2037 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2038 as the sequence to the remote target in order to interrupt the execution.
2039 Ctrl-C is a default. Some system prefers BREAK which is high level of
2040 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2041 Magic SysRq g. It is BREAK signal and character 'g'.
2043 set remote interrupt-on-connect [on | off]
2044 show remote interrupt-on-connect
2045 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2046 remote target when gdb connects to it. This is needed when you debug
2049 set remotebreak [on | off]
2051 Deprecated. Use "set/show remote interrupt-sequence" instead.
2053 tvariable $NAME [ = EXP ]
2054 Create or modify a trace state variable.
2057 List trace state variables and their values.
2059 delete tvariable $NAME ...
2060 Delete one or more trace state variables.
2063 Evaluate the given expressions without collecting anything into the
2064 trace buffer. (Valid in tracepoint actions only.)
2066 ftrace FN / FILE:LINE / *ADDR
2067 Define a fast tracepoint at the given function, line, or address.
2069 * New expression syntax
2071 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2072 GDB now parses 0b101010 identically with 42.
2076 set follow-exec-mode new|same
2077 show follow-exec-mode
2078 Control whether GDB reuses the same inferior across an exec call or
2079 creates a new one. This is useful to be able to restart the old
2080 executable after the inferior having done an exec call.
2082 set default-collect EXPR, ...
2083 show default-collect
2084 Define a list of expressions to be collected at each tracepoint.
2085 This is a useful way to ensure essential items are not overlooked,
2086 such as registers or a critical global variable.
2088 set disconnected-tracing
2089 show disconnected-tracing
2090 If set to 1, the target is instructed to continue tracing if it
2091 loses its connection to GDB. If 0, the target is to stop tracing
2094 set circular-trace-buffer
2095 show circular-trace-buffer
2096 If set to on, the target is instructed to use a circular trace buffer
2097 and discard the oldest trace frames instead of stopping the trace due
2098 to a full trace buffer. If set to off, the trace stops when the buffer
2099 fills up. Some targets may not support this.
2101 set script-extension off|soft|strict
2102 show script-extension
2103 If set to "off", the debugger does not perform any script language
2104 recognition, and all sourced files are assumed to be GDB scripts.
2105 If set to "soft" (the default), files are sourced according to
2106 filename extension, falling back to GDB scripts if the first
2108 If set to "strict", files are sourced according to filename extension.
2110 set ada trust-PAD-over-XVS on|off
2111 show ada trust-PAD-over-XVS
2112 If off, activate a workaround against a bug in the debugging information
2113 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2114 the GCC sources for more information about the GNAT encoding and
2115 PAD types in particular). It is always safe to set this option to
2116 off, but this introduces a slight performance penalty. The default
2119 * Python API Improvements
2121 ** GDB provides the new class gdb.LazyString. This is useful in
2122 some pretty-printing cases. The new method gdb.Value.lazy_string
2123 provides a simple way to create objects of this type.
2125 ** The fields returned by gdb.Type.fields now have an
2126 `is_base_class' attribute.
2128 ** The new method gdb.Type.range returns the range of an array type.
2130 ** The new method gdb.parse_and_eval can be used to parse and
2131 evaluate an expression.
2133 * New remote packets
2136 Define a trace state variable.
2139 Get the current value of a trace state variable.
2142 Set desired tracing behavior upon disconnection.
2145 Set the trace buffer to be linear or circular.
2148 Get data about the tracepoints currently in use.
2152 Process record now works correctly with hardware watchpoints.
2154 Multiple bug fixes have been made to the mips-irix port, making it
2155 much more reliable. In particular:
2156 - Debugging threaded applications is now possible again. Previously,
2157 GDB would hang while starting the program, or while waiting for
2158 the program to stop at a breakpoint.
2159 - Attaching to a running process no longer hangs.
2160 - An error occurring while loading a core file has been fixed.
2161 - Changing the value of the PC register now works again. This fixes
2162 problems observed when using the "jump" command, or when calling
2163 a function from GDB, or even when assigning a new value to $pc.
2164 - With the "finish" and "return" commands, the return value for functions
2165 returning a small array is now correctly printed.
2166 - It is now possible to break on shared library code which gets executed
2167 during a shared library init phase (code executed while executing
2168 their .init section). Previously, the breakpoint would have no effect.
2169 - GDB is now able to backtrace through the signal handler for
2170 non-threaded programs.
2172 PIE (Position Independent Executable) programs debugging is now supported.
2173 This includes debugging execution of PIC (Position Independent Code) shared
2174 libraries although for that, it should be possible to run such libraries as an
2177 *** Changes in GDB 7.0
2179 * GDB now has an interface for JIT compilation. Applications that
2180 dynamically generate code can create symbol files in memory and register
2181 them with GDB. For users, the feature should work transparently, and
2182 for JIT developers, the interface is documented in the GDB manual in the
2183 "JIT Compilation Interface" chapter.
2185 * Tracepoints may now be conditional. The syntax is as for
2186 breakpoints; either an "if" clause appended to the "trace" command,
2187 or the "condition" command is available. GDB sends the condition to
2188 the target for evaluation using the same bytecode format as is used
2189 for tracepoint actions.
2191 * The disassemble command now supports: an optional /r modifier, print the
2192 raw instructions in hex as well as in symbolic form, and an optional /m
2193 modifier to print mixed source+assembly.
2195 * Process record and replay
2197 In a architecture environment that supports ``process record and
2198 replay'', ``process record and replay'' target can record a log of
2199 the process execution, and replay it with both forward and reverse
2202 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2203 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2204 set execution-direction {forward|reverse}, for targets that support
2207 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2208 feature is available with a native GDB running on kernel version
2211 * GDB now has support for multi-byte and wide character sets on the
2212 target. Strings whose character type is wchar_t, char16_t, or
2213 char32_t are now correctly printed. GDB supports wide- and unicode-
2214 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2215 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2216 `printf'. This feature requires iconv to work properly; if your
2217 system does not have a working iconv, GDB can use GNU libiconv. See
2218 the installation instructions for more information.
2220 * GDB now supports automatic retrieval of shared library files from
2221 remote targets. To use this feature, specify a system root that begins
2222 with the `remote:' prefix, either via the `set sysroot' command or via
2223 the `--with-sysroot' configure-time option.
2225 * "info sharedlibrary" now takes an optional regex of libraries to show,
2226 and it now reports if a shared library has no debugging information.
2228 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2229 now complete on file names.
2231 * When completing in expressions, gdb will attempt to limit
2232 completions to allowable structure or union fields, where appropriate.
2233 For instance, consider:
2235 # struct example { int f1; double f2; };
2236 # struct example variable;
2239 If the user types TAB at the end of this command line, the available
2240 completions will be "f1" and "f2".
2242 * Inlined functions are now supported. They show up in backtraces, and
2243 the "step", "next", and "finish" commands handle them automatically.
2245 * GDB now supports the token-splicing (##) and stringification (#)
2246 operators when expanding macros. It also supports variable-arity
2249 * GDB now supports inspecting extra signal information, exported by
2250 the new $_siginfo convenience variable. The feature is currently
2251 implemented on linux ARM, i386 and amd64.
2253 * GDB can now display the VFP floating point registers and NEON vector
2254 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2255 can provide these registers (requires Linux 2.6.30 or later). Remote
2256 and simulator targets may also provide them.
2258 * New remote packets
2261 Search memory for a sequence of bytes.
2264 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2265 operation over reliable transport links. Use of this packet is
2266 controlled by the `set remote noack-packet' command.
2269 Kill the process with the specified process ID. Use this in preference
2270 to `k' when multiprocess protocol extensions are supported.
2273 Obtains additional operating system information
2277 Read or write additional signal information.
2279 * Removed remote protocol undocumented extension
2281 An undocumented extension to the remote protocol's `S' stop reply
2282 packet that permited the stub to pass a process id was removed.
2283 Remote servers should use the `T' stop reply packet instead.
2285 * GDB now supports multiple function calling conventions according to the
2286 DWARF-2 DW_AT_calling_convention function attribute.
2288 * The SH target utilizes the aforementioned change to distinguish between gcc
2289 and Renesas calling convention. It also adds the new CLI commands
2290 `set/show sh calling-convention'.
2292 * GDB can now read compressed debug sections, as produced by GNU gold
2293 with the --compress-debug-sections=zlib flag.
2295 * 64-bit core files are now supported on AIX.
2297 * Thread switching is now supported on Tru64.
2299 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2300 which will be allocated using malloc later in program execution.
2302 * The qXfer:libraries:read remote procotol packet now allows passing a
2303 list of section offsets.
2305 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2306 conditions handling signals delivered during attach or thread creation
2307 have also been fixed.
2309 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2310 From the user's standpoint, all unqualified instances of True and False
2311 are treated as the standard definitions, regardless of context.
2313 * GDB now parses C++ symbol and type names more flexibly. For
2316 template<typename T> class C { };
2319 GDB will now correctly handle all of:
2321 ptype C<char const *>
2322 ptype C<char const*>
2323 ptype C<const char *>
2324 ptype C<const char*>
2326 * New features in the GDB remote stub, gdbserver
2328 - The "--wrapper" command-line argument tells gdbserver to use a
2329 wrapper program to launch programs for debugging.
2331 - On PowerPC and S/390 targets, it is now possible to use a single
2332 gdbserver executable to debug both 32-bit and 64-bit programs.
2333 (This requires gdbserver itself to be built as a 64-bit executable.)
2335 - gdbserver uses the new noack protocol mode for TCP connections to
2336 reduce communications latency, if also supported and enabled in GDB.
2338 - Support for the sparc64-linux-gnu target is now included in
2341 - The amd64-linux build of gdbserver now supports debugging both
2342 32-bit and 64-bit programs.
2344 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2345 now support hardware watchpoints, and will use them automatically
2350 GDB now has support for scripting using Python. Whether this is
2351 available is determined at configure time.
2353 New GDB commands can now be written in Python.
2355 * Ada tasking support
2357 Ada tasks can now be inspected in GDB. The following commands have
2361 Print the list of Ada tasks.
2363 Print detailed information about task number N.
2365 Print the task number of the current task.
2367 Switch the context of debugging to task number N.
2369 * Support for user-defined prefixed commands. The "define" command can
2370 add new commands to existing prefixes, e.g. "target".
2372 * Multi-inferior, multi-process debugging.
2374 GDB now has generalized support for multi-inferior debugging. See
2375 "Debugging Multiple Inferiors" in the manual for more information.
2376 Although availability still depends on target support, the command
2377 set is more uniform now. The GNU/Linux specific multi-forks support
2378 has been migrated to this new framework. This implied some user
2379 visible changes; see "New commands" and also "Removed commands"
2382 * Target descriptions can now describe the target OS ABI. See the
2383 "Target Description Format" section in the user manual for more
2386 * Target descriptions can now describe "compatible" architectures
2387 to indicate that the target can execute applications for a different
2388 architecture in addition to those for the main target architecture.
2389 See the "Target Description Format" section in the user manual for
2392 * Multi-architecture debugging.
2394 GDB now includes general supports for debugging applications on
2395 hybrid systems that use more than one single processor architecture
2396 at the same time. Each such hybrid architecture still requires
2397 specific support to be added. The only hybrid architecture supported
2398 in this version of GDB is the Cell Broadband Engine.
2400 * GDB now supports integrated debugging of Cell/B.E. applications that
2401 use both the PPU and SPU architectures. To enable support for hybrid
2402 Cell/B.E. debugging, you need to configure GDB to support both the
2403 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2404 --enable-targets configure option.
2406 * Non-stop mode debugging.
2408 For some targets, GDB now supports an optional mode of operation in
2409 which you can examine stopped threads while other threads continue
2410 to execute freely. This is referred to as non-stop mode, with the
2411 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2412 section in the user manual for more information.
2414 To be able to support remote non-stop debugging, a remote stub needs
2415 to implement the non-stop mode remote protocol extensions, as
2416 described in the "Remote Non-Stop" section of the user manual. The
2417 GDB remote stub, gdbserver, has been adjusted to support these
2418 extensions on linux targets.
2420 * New commands (for set/show, see "New options" below)
2422 catch syscall [NAME(S) | NUMBER(S)]
2423 Catch system calls. Arguments, which should be names of system
2424 calls or their numbers, mean catch only those syscalls. Without
2425 arguments, every syscall will be caught. When the inferior issues
2426 any of the specified syscalls, GDB will stop and announce the system
2427 call, both when it is called and when its call returns. This
2428 feature is currently available with a native GDB running on the
2429 Linux Kernel, under the following architectures: x86, x86_64,
2430 PowerPC and PowerPC64.
2432 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2434 Search memory for a sequence of bytes.
2436 maint set python print-stack
2437 maint show python print-stack
2438 Show a stack trace when an error is encountered in a Python script.
2441 Invoke CODE by passing it to the Python interpreter.
2446 These allow macros to be defined, undefined, and listed
2450 Show operating system information about processes.
2453 List the inferiors currently under GDB's control.
2456 Switch focus to inferior number NUM.
2459 Detach from inferior number NUM.
2462 Kill inferior number NUM.
2466 set spu stop-on-load
2467 show spu stop-on-load
2468 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2470 set spu auto-flush-cache
2471 show spu auto-flush-cache
2472 Control whether to automatically flush the software-managed cache
2473 during Cell/B.E. debugging.
2475 set sh calling-convention
2476 show sh calling-convention
2477 Control the calling convention used when calling SH target functions.
2480 show debug timestamp
2481 Control display of timestamps with GDB debugging output.
2483 set disassemble-next-line
2484 show disassemble-next-line
2485 Control display of disassembled source lines or instructions when
2488 set remote noack-packet
2489 show remote noack-packet
2490 Set/show the use of remote protocol QStartNoAckMode packet. See above
2491 under "New remote packets."
2493 set remote query-attached-packet
2494 show remote query-attached-packet
2495 Control use of remote protocol `qAttached' (query-attached) packet.
2497 set remote read-siginfo-object
2498 show remote read-siginfo-object
2499 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2502 set remote write-siginfo-object
2503 show remote write-siginfo-object
2504 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2507 set remote reverse-continue
2508 show remote reverse-continue
2509 Control use of remote protocol 'bc' (reverse-continue) packet.
2511 set remote reverse-step
2512 show remote reverse-step
2513 Control use of remote protocol 'bs' (reverse-step) packet.
2515 set displaced-stepping
2516 show displaced-stepping
2517 Control displaced stepping mode. Displaced stepping is a way to
2518 single-step over breakpoints without removing them from the debuggee.
2519 Also known as "out-of-line single-stepping".
2522 show debug displaced
2523 Control display of debugging info for displaced stepping.
2525 maint set internal-error
2526 maint show internal-error
2527 Control what GDB does when an internal error is detected.
2529 maint set internal-warning
2530 maint show internal-warning
2531 Control what GDB does when an internal warning is detected.
2536 Use a wrapper program to launch programs for debugging.
2538 set multiple-symbols (all|ask|cancel)
2539 show multiple-symbols
2540 The value of this variable can be changed to adjust the debugger behavior
2541 when an expression or a breakpoint location contains an ambiguous symbol
2542 name (an overloaded function name, for instance).
2544 set breakpoint always-inserted
2545 show breakpoint always-inserted
2546 Keep breakpoints always inserted in the target, as opposed to inserting
2547 them when resuming the target, and removing them when the target stops.
2548 This option can improve debugger performance on slow remote targets.
2550 set arm fallback-mode (arm|thumb|auto)
2551 show arm fallback-mode
2552 set arm force-mode (arm|thumb|auto)
2554 These commands control how ARM GDB determines whether instructions
2555 are ARM or Thumb. The default for both settings is auto, which uses
2556 the current CPSR value for instructions without symbols; previous
2557 versions of GDB behaved as if "set arm fallback-mode arm".
2559 set disable-randomization
2560 show disable-randomization
2561 Standalone programs run with the virtual address space randomization enabled
2562 by default on some platforms. This option keeps the addresses stable across
2563 multiple debugging sessions.
2567 Control whether other threads are stopped or not when some thread hits
2572 Requests that asynchronous execution is enabled in the target, if available.
2573 In this case, it's possible to resume target in the background, and interact
2574 with GDB while the target is running. "show target-async" displays the
2575 current state of asynchronous execution of the target.
2577 set target-wide-charset
2578 show target-wide-charset
2579 The target-wide-charset is the name of the character set that GDB
2580 uses when printing characters whose type is wchar_t.
2582 set tcp auto-retry (on|off)
2584 set tcp connect-timeout
2585 show tcp connect-timeout
2586 These commands allow GDB to retry failed TCP connections to a remote stub
2587 with a specified timeout period; this is useful if the stub is launched
2588 in parallel with GDB but may not be ready to accept connections immediately.
2590 set libthread-db-search-path
2591 show libthread-db-search-path
2592 Control list of directories which GDB will search for appropriate
2595 set schedule-multiple (on|off)
2596 show schedule-multiple
2597 Allow GDB to resume all threads of all processes or only threads of
2598 the current process.
2602 Use more aggressive caching for accesses to the stack. This improves
2603 performance of remote debugging (particularly backtraces) without
2604 affecting correctness.
2606 set interactive-mode (on|off|auto)
2607 show interactive-mode
2608 Control whether GDB runs in interactive mode (on) or not (off).
2609 When in interactive mode, GDB waits for the user to answer all
2610 queries. Otherwise, GDB does not wait and assumes the default
2611 answer. When set to auto (the default), GDB determines which
2612 mode to use based on the stdin settings.
2617 For program forks, this is replaced by the new more generic `info
2618 inferiors' command. To list checkpoints, you can still use the
2619 `info checkpoints' command, which was an alias for the `info forks'
2623 Replaced by the new `inferior' command. To switch between
2624 checkpoints, you can still use the `restart' command, which was an
2625 alias for the `fork' command.
2628 This is removed, since some targets don't have a notion of
2629 processes. To switch between processes, you can still use the
2630 `inferior' command using GDB's own inferior number.
2633 For program forks, this is replaced by the new more generic `kill
2634 inferior' command. To delete a checkpoint, you can still use the
2635 `delete checkpoint' command, which was an alias for the `delete
2639 For program forks, this is replaced by the new more generic `detach
2640 inferior' command. To detach a checkpoint, you can still use the
2641 `detach checkpoint' command, which was an alias for the `detach
2644 * New native configurations
2646 x86/x86_64 Darwin i[34567]86-*-darwin*
2648 x86_64 MinGW x86_64-*-mingw*
2652 Lattice Mico32 lm32-*
2653 x86 DICOS i[34567]86-*-dicos*
2654 x86_64 DICOS x86_64-*-dicos*
2657 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2658 (mingw32ce) debugging.
2664 These commands were actually not implemented on any target.
2666 *** Changes in GDB 6.8
2668 * New native configurations
2670 NetBSD/hppa hppa*-*netbsd*
2671 Xtensa GNU/Linux xtensa*-*-linux*
2675 NetBSD/hppa hppa*-*-netbsd*
2676 Xtensa GNU/Lunux xtensa*-*-linux*
2678 * Change in command line behavior -- corefiles vs. process ids.
2680 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2681 attaching to process NUMBER fails, GDB no longer attempts to open a
2682 core file named NUMBER. Attaching to a program using the -c option
2683 is no longer supported. Instead, use the '-p' or '--pid' options.
2685 * GDB can now be built as a native debugger for debugging Windows x86
2686 (mingw32) Portable Executable (PE) programs.
2688 * Pending breakpoints no longer change their number when their address
2691 * GDB now supports breakpoints with multiple locations,
2692 including breakpoints on C++ constructors, inside C++ templates,
2693 and in inlined functions.
2695 * GDB's ability to debug optimized code has been improved. GDB more
2696 accurately identifies function bodies and lexical blocks that occupy
2697 more than one contiguous range of addresses.
2699 * Target descriptions can now describe registers for PowerPC.
2701 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2702 registers on PowerPC targets.
2704 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2705 targets even when the libthread_db library is not available.
2707 * The GDB remote stub, gdbserver, now supports the new file transfer
2708 commands (remote put, remote get, and remote delete).
2710 * The GDB remote stub, gdbserver, now supports run and attach in
2711 extended-remote mode.
2713 * hppa*64*-*-hpux11* target broken
2714 The debugger is unable to start a program and fails with the following
2715 error: "Error trying to get information about dynamic linker".
2716 The gdb-6.7 release is also affected.
2718 * GDB now supports the --enable-targets= configure option to allow
2719 building a single GDB executable that supports multiple remote
2720 target architectures.
2722 * GDB now supports debugging C and C++ programs which use the
2723 Decimal Floating Point extension. In addition, the PowerPC target
2724 now has a set of pseudo-registers to inspect decimal float values
2725 stored in two consecutive float registers.
2727 * The -break-insert MI command can optionally create pending
2730 * Improved support for debugging Ada
2731 Many improvements to the Ada language support have been made. These
2733 - Better support for Ada2005 interface types
2734 - Improved handling of arrays and slices in general
2735 - Better support for Taft-amendment types
2736 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2738 - Improved command completion in Ada
2741 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2746 set print frame-arguments (all|scalars|none)
2747 show print frame-arguments
2748 The value of this variable can be changed to control which argument
2749 values should be printed by the debugger when displaying a frame.
2754 Transfer files to and from a remote target, and delete remote files.
2761 Transfer files to and from a remote target, and delete remote files.
2763 * New remote packets
2770 Open, close, read, write, and delete files on the remote system.
2773 Attach to an existing process on the remote system, in extended-remote
2777 Run a new process on the remote system, in extended-remote mode.
2779 *** Changes in GDB 6.7
2781 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2782 bfd, libiberty and opcodes, as revealed by static analysis donated by
2783 Coverity, Inc. (http://scan.coverity.com).
2785 * When looking up multiply-defined global symbols, GDB will now prefer the
2786 symbol definition in the current shared library if it was built using the
2787 -Bsymbolic linker option.
2789 * When the Text User Interface (TUI) is not configured, GDB will now
2790 recognize the -tui command-line option and print a message that the TUI
2793 * The GDB remote stub, gdbserver, now has lower overhead for high
2794 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2796 * GDB for MIPS targets now autodetects whether a remote target provides
2797 32-bit or 64-bit register values.
2799 * Support for C++ member pointers has been improved.
2801 * GDB now understands XML target descriptions, which specify the
2802 target's overall architecture. GDB can read a description from
2803 a local file or over the remote serial protocol.
2805 * Vectors of single-byte data use a new integer type which is not
2806 automatically displayed as character or string data.
2808 * The /s format now works with the print command. It displays
2809 arrays of single-byte integers and pointers to single-byte integers
2812 * Target descriptions can now describe target-specific registers,
2813 for architectures which have implemented the support (currently
2814 only ARM, M68K, and MIPS).
2816 * GDB and the GDB remote stub, gdbserver, now support the XScale
2819 * The GDB remote stub, gdbserver, has been updated to support
2820 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2821 has been rewritten to use the standard GDB remote protocol.
2823 * GDB can now step into C++ functions which are called through thunks.
2825 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2827 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2828 layout. It also supports a TextSeg= and DataSeg= response when only
2829 segment base addresses (rather than offsets) are available.
2831 * The /i format now outputs any trailing branch delay slot instructions
2832 immediately following the last instruction within the count specified.
2834 * The GDB remote protocol "T" stop reply packet now supports a
2835 "library" response. Combined with the new "qXfer:libraries:read"
2836 packet, this response allows GDB to debug shared libraries on targets
2837 where the operating system manages the list of loaded libraries (e.g.
2838 Windows and SymbianOS).
2840 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2841 (DLLs) on Windows and Windows CE targets.
2843 * GDB now supports a faster verification that a .debug file matches its binary
2844 according to its build-id signature, if the signature is present.
2850 Enable or disable hardware flow control (RTS/CTS) on the serial port
2851 when debugging using remote targets.
2853 set mem inaccessible-by-default
2854 show mem inaccessible-by-default
2855 If the target supplies a memory map, for instance via the remote
2856 protocol's "qXfer:memory-map:read" packet, setting this variable
2857 prevents GDB from accessing memory outside the memory map. This
2858 is useful for targets with memory mapped registers or which react
2859 badly to accesses of unmapped address space.
2861 set breakpoint auto-hw
2862 show breakpoint auto-hw
2863 If the target supplies a memory map, for instance via the remote
2864 protocol's "qXfer:memory-map:read" packet, setting this variable
2865 lets GDB use hardware breakpoints automatically for memory regions
2866 where it can not use software breakpoints. This covers both the
2867 "break" command and internal breakpoints used for other commands
2868 including "next" and "finish".
2871 catch exception unhandled
2872 Stop the program execution when Ada exceptions are raised.
2875 Stop the program execution when an Ada assertion failed.
2879 Set an alternate system root for target files. This is a more
2880 general version of "set solib-absolute-prefix", which is now
2881 an alias to "set sysroot".
2884 Provide extended SPU facility status information. This set of
2885 commands is available only when debugging the Cell/B.E. SPU
2888 * New native configurations
2890 OpenBSD/sh sh*-*openbsd*
2893 unset tdesc filename
2895 Use the specified local file as an XML target description, and do
2896 not query the target for its built-in description.
2900 OpenBSD/sh sh*-*-openbsd*
2901 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2902 Toshiba Media Processor mep-elf
2904 * New remote packets
2907 Ignore the specified signals; pass them directly to the debugged program
2908 without stopping other threads or reporting them to GDB.
2910 qXfer:features:read:
2911 Read an XML target description from the target, which describes its
2916 Read or write contents of an spufs file on the target system. These
2917 packets are available only on the Cell/B.E. SPU architecture.
2919 qXfer:libraries:read:
2920 Report the loaded shared libraries. Combined with new "T" packet
2921 response, this packet allows GDB to debug shared libraries on
2922 targets where the operating system manages the list of loaded
2923 libraries (e.g. Windows and SymbianOS).
2927 Support for these obsolete configurations has been removed.
2935 i[34567]86-*-lynxos*
2936 i[34567]86-*-netware*
2937 i[34567]86-*-sco3.2v5*
2938 i[34567]86-*-sco3.2v4*
2940 i[34567]86-*-sysv4.2*
2943 i[34567]86-*-unixware2*
2944 i[34567]86-*-unixware*
2953 * Other removed features
2960 Various m68k-only ROM monitors.
2967 Various Renesas ROM monitors and debugging interfaces for SH and
2972 Support for a Macraigor serial interface to on-chip debugging.
2973 GDB does not directly support the newer parallel or USB
2978 A debug information format. The predecessor to DWARF 2 and
2979 DWARF 3, which are still supported.
2981 Support for the HP aCC compiler on HP-UX/PA-RISC
2983 SOM-encapsulated symbolic debugging information, automatic
2984 invocation of pxdb, and the aCC custom C++ ABI. This does not
2985 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2986 with aCC can still be debugged on an assembly level.
2988 MIPS ".pdr" sections
2990 A MIPS-specific format used to describe stack frame layout
2991 in debugging information.
2995 GDB could work with an older version of Guile to debug
2996 the interpreter and Scheme programs running in it.
2998 set mips stack-arg-size
2999 set mips saved-gpreg-size
3001 Use "set mips abi" to control parameter passing for MIPS.
3003 *** Changes in GDB 6.6
3008 Cell Broadband Engine SPU spu-elf
3010 * GDB can now be configured as a cross-debugger targeting native Windows
3011 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3012 running on a Windows system over TCP/IP to debug Windows programs.
3014 * The GDB remote stub, gdbserver, has been updated to support Windows and
3015 Cygwin debugging. Both single-threaded and multi-threaded programs are
3018 * The "set trust-readonly-sections" command works again. This command was
3019 broken in GDB 6.3, 6.4, and 6.5.
3021 * The "load" command now supports writing to flash memory, if the remote
3022 stub provides the required support.
3024 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3025 longer requires symbolic debug information (e.g. DWARF-2).
3030 unset substitute-path
3031 show substitute-path
3032 Manage a list of substitution rules that GDB uses to rewrite the name
3033 of the directories where the sources are located. This can be useful
3034 for instance when the sources were moved to a different location
3035 between compilation and debugging.
3039 Print each CLI command as it is executed. Each command is prefixed with
3040 a number of `+' symbols representing the nesting depth.
3041 The source command now has a `-v' option to enable the same feature.
3045 The ARM Demon monitor support (RDP protocol, "target rdp").
3047 Kernel Object Display, an embedded debugging feature which only worked with
3048 an obsolete version of Cisco IOS.
3050 The 'set download-write-size' and 'show download-write-size' commands.
3052 * New remote packets
3055 Tell a stub about GDB client features, and request remote target features.
3056 The first feature implemented is PacketSize, which allows the target to
3057 specify the size of packets it can handle - to minimize the number of
3058 packets required and improve performance when connected to a remote
3062 Fetch an OS auxilliary vector from the remote stub. This packet is a
3063 more efficient replacement for qPart:auxv:read.
3065 qXfer:memory-map:read:
3066 Fetch a memory map from the remote stub, including information about
3067 RAM, ROM, and flash memory devices.
3072 Erase and program a flash memory device.
3074 * Removed remote packets
3077 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3078 used it, and only gdbserver implemented it.
3080 *** Changes in GDB 6.5
3084 Renesas M32C/M16C m32c-elf
3086 Morpho Technologies ms1 ms1-elf
3090 init-if-undefined Initialize a convenience variable, but
3091 only if it doesn't already have a value.
3093 The following commands are presently only implemented for native GNU/Linux:
3095 checkpoint Save a snapshot of the program state.
3097 restart <n> Return the program state to a
3098 previously saved state.
3100 info checkpoints List currently saved checkpoints.
3102 delete-checkpoint <n> Delete a previously saved checkpoint.
3104 set|show detach-on-fork Tell gdb whether to detach from a newly
3105 forked process, or to keep debugging it.
3107 info forks List forks of the user program that
3108 are available to be debugged.
3110 fork <n> Switch to debugging one of several
3111 forks of the user program that are
3112 available to be debugged.
3114 delete-fork <n> Delete a fork from the list of forks
3115 that are available to be debugged (and
3116 kill the forked process).
3118 detach-fork <n> Delete a fork from the list of forks
3119 that are available to be debugged (and
3120 allow the process to continue).
3124 Morpho Technologies ms2 ms1-elf
3126 * Improved Windows host support
3128 GDB now builds as a cross debugger hosted on i686-mingw32, including
3129 native console support, and remote communications using either
3130 network sockets or serial ports.
3132 * Improved Modula-2 language support
3134 GDB can now print most types in the Modula-2 syntax. This includes:
3135 basic types, set types, record types, enumerated types, range types,
3136 pointer types and ARRAY types. Procedure var parameters are correctly
3137 printed and hexadecimal addresses and character constants are also
3138 written in the Modula-2 syntax. Best results can be obtained by using
3139 GNU Modula-2 together with the -gdwarf-2 command line option.
3143 The ARM rdi-share module.
3145 The Netware NLM debug server.
3147 *** Changes in GDB 6.4
3149 * New native configurations
3151 OpenBSD/arm arm*-*-openbsd*
3152 OpenBSD/mips64 mips64-*-openbsd*
3156 Morpho Technologies ms1 ms1-elf
3158 * New command line options
3160 --batch-silent As for --batch, but totally silent.
3161 --return-child-result The debugger will exist with the same value
3162 the child (debugged) program exited with.
3163 --eval-command COMMAND, -ex COMMAND
3164 Execute a single GDB CLI command. This may be
3165 specified multiple times and in conjunction
3166 with the --command (-x) option.
3168 * Deprecated commands removed
3170 The following commands, that were deprecated in 2000, have been
3174 set|show arm disassembly-flavor set|show arm disassembler
3175 othernames set arm disassembler
3176 set|show remotedebug set|show debug remote
3177 set|show archdebug set|show debug arch
3178 set|show eventdebug set|show debug event
3181 * New BSD user-level threads support
3183 It is now possible to debug programs using the user-level threads
3184 library on OpenBSD and FreeBSD. Currently supported (target)
3187 FreeBSD/amd64 x86_64-*-freebsd*
3188 FreeBSD/i386 i386-*-freebsd*
3189 OpenBSD/i386 i386-*-openbsd*
3191 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3192 are not yet supported.
3194 * New support for Matsushita MN10300 w/sim added
3195 (Work in progress). mn10300-elf.
3197 * REMOVED configurations and files
3199 VxWorks and the XDR protocol *-*-vxworks
3200 Motorola MCORE mcore-*-*
3201 National Semiconductor NS32000 ns32k-*-*
3203 * New "set print array-indexes" command
3205 After turning this setting "on", GDB prints the index of each element
3206 when displaying arrays. The default is "off" to preserve the previous
3209 * VAX floating point support
3211 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3213 * User-defined command support
3215 In addition to using $arg0..$arg9 for argument passing, it is now possible
3216 to use $argc to determine now many arguments have been passed. See the
3217 section on user-defined commands in the user manual for more information.
3219 *** Changes in GDB 6.3:
3221 * New command line option
3223 GDB now accepts -l followed by a number to set the timeout for remote
3226 * GDB works with GCC -feliminate-dwarf2-dups
3228 GDB now supports a more compact representation of DWARF-2 debug
3229 information using DW_FORM_ref_addr references. These are produced
3230 by GCC with the option -feliminate-dwarf2-dups and also by some
3231 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3232 to use -feliminate-dwarf2-dups.
3234 * Internationalization
3236 When supported by the host system, GDB will be built with
3237 internationalization (libintl). The task of marking up the sources is
3238 continued, we're looking forward to our first translation.
3242 Initial support for debugging programs compiled with the GNAT
3243 implementation of the Ada programming language has been integrated
3244 into GDB. In this release, support is limited to expression evaluation.
3246 * New native configurations
3248 GNU/Linux/m32r m32r-*-linux-gnu
3252 GDB's remote protocol now includes support for the 'p' packet. This
3253 packet is used to fetch individual registers from a remote inferior.
3255 * END-OF-LIFE registers[] compatibility module
3257 GDB's internal register infrastructure has been completely rewritten.
3258 The new infrastructure making possible the implementation of key new
3259 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3262 GDB 6.3 will be the last release to include the the registers[]
3263 compatibility module that allowed out-of-date configurations to
3264 continue to work. This change directly impacts the following
3274 powerpc bdm protocol
3276 Unless there is activity to revive these configurations, they will be
3277 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3279 * OBSOLETE configurations and files
3281 Configurations that have been declared obsolete in this release have
3282 been commented out. Unless there is activity to revive these
3283 configurations, the next release of GDB will have their sources
3284 permanently REMOVED.
3293 *** Changes in GDB 6.2.1:
3295 * MIPS `break main; run' gave an heuristic-fence-post warning
3297 When attempting to run even a simple program, a warning about
3298 heuristic-fence-post being hit would be reported. This problem has
3301 * MIPS IRIX 'long double' crashed GDB
3303 When examining a long double variable, GDB would get a segmentation
3304 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3305 IRIX long double values).
3309 A bug in the VAX stack code was causing problems with the "next"
3310 command. This problem has been fixed.
3312 *** Changes in GDB 6.2:
3314 * Fix for ``many threads''
3316 On GNU/Linux systems that use the NPTL threads library, a program
3317 rapidly creating and deleting threads would confuse GDB leading to the
3320 ptrace: No such process.
3321 thread_db_get_info: cannot get thread info: generic error
3323 This problem has been fixed.
3325 * "-async" and "-noasync" options removed.
3327 Support for the broken "-noasync" option has been removed (it caused
3330 * New ``start'' command.
3332 This command runs the program until the begining of the main procedure.
3334 * New BSD Kernel Data Access Library (libkvm) interface
3336 Using ``target kvm'' it is now possible to debug kernel core dumps and
3337 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3338 platforms. Currently supported (native-only) configurations are:
3340 FreeBSD/amd64 x86_64-*-freebsd*
3341 FreeBSD/i386 i?86-*-freebsd*
3342 NetBSD/i386 i?86-*-netbsd*
3343 NetBSD/m68k m68*-*-netbsd*
3344 NetBSD/sparc sparc-*-netbsd*
3345 OpenBSD/amd64 x86_64-*-openbsd*
3346 OpenBSD/i386 i?86-*-openbsd*
3347 OpenBSD/m68k m68*-openbsd*
3348 OpenBSD/sparc sparc-*-openbsd*
3350 * Signal trampoline code overhauled
3352 Many generic problems with GDB's signal handling code have been fixed.
3353 These include: backtraces through non-contiguous stacks; recognition
3354 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3355 call; backtrace through a signal trampoline; step into and out of
3356 signal handlers; and single-stepping in the signal trampoline.
3358 Please note that kernel bugs are a limiting factor here. These
3359 features have been shown to work on an s390 GNU/Linux system that
3360 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3362 * Cygwin support for DWARF 2 added.
3364 * New native configurations
3366 GNU/Linux/hppa hppa*-*-linux*
3367 OpenBSD/hppa hppa*-*-openbsd*
3368 OpenBSD/m68k m68*-*-openbsd*
3369 OpenBSD/m88k m88*-*-openbsd*
3370 OpenBSD/powerpc powerpc-*-openbsd*
3371 NetBSD/vax vax-*-netbsd*
3372 OpenBSD/vax vax-*-openbsd*
3374 * END-OF-LIFE frame compatibility module
3376 GDB's internal frame infrastructure has been completely rewritten.
3377 The new infrastructure making it possible to support key new features
3378 including DWARF 2 Call Frame Information. To aid in the task of
3379 migrating old configurations to this new infrastructure, a
3380 compatibility module, that allowed old configurations to continue to
3381 work, was also included.
3383 GDB 6.2 will be the last release to include this frame compatibility
3384 module. This change directly impacts the following configurations:
3394 Unless there is activity to revive these configurations, they will be
3395 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3397 * REMOVED configurations and files
3399 Sun 3, running SunOS 3 m68*-*-sunos3*
3400 Sun 3, running SunOS 4 m68*-*-sunos4*
3401 Sun 2, running SunOS 3 m68000-*-sunos3*
3402 Sun 2, running SunOS 4 m68000-*-sunos4*
3403 Motorola 680x0 running LynxOS m68*-*-lynxos*
3404 AT&T 3b1/Unix pc m68*-att-*
3405 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3406 decstation mips-dec-* mips-little-*
3407 riscos mips-*-riscos* mips-*-sysv*
3408 sonymips mips-sony-*
3409 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3411 *** Changes in GDB 6.1.1:
3413 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3415 The TUI (Text-mode User Interface) is now built as part of a default
3416 GDB configuration. It is enabled by either selecting the TUI with the
3417 command line option "-i=tui" or by running the separate "gdbtui"
3418 program. For more information on the TUI, see the manual "Debugging
3421 * Pending breakpoint support (also included in GDB 6.1)
3423 Support has been added to allow you to specify breakpoints in shared
3424 libraries that have not yet been loaded. If a breakpoint location
3425 cannot be found, and the "breakpoint pending" option is set to auto,
3426 GDB queries you if you wish to make the breakpoint pending on a future
3427 shared-library load. If and when GDB resolves the breakpoint symbol,
3428 the pending breakpoint is removed as one or more regular breakpoints
3431 Pending breakpoints are very useful for GCJ Java debugging.
3433 * Fixed ISO-C build problems
3435 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3436 non ISO-C code that stopped them being built using a more strict ISO-C
3437 compiler (e.g., IBM's C compiler).
3439 * Fixed build problem on IRIX 5
3441 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3442 wasn't able to compile compile on an IRIX 5 system.
3444 * Added execute permission to gdb/gdbserver/configure
3446 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3447 permission. This bug would cause configure to fail on a number of
3448 systems (Solaris, IRIX). Ref: server/519.
3450 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3452 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3453 has been updated to use constant array sizes.
3455 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3457 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3458 its generated DWARF Call Frame Info. This encoding was causing GDB to
3459 panic, that panic has been fixed. Ref: gdb/1628.
3461 * Fixed a problem when examining parameters in shared library code.
3463 When examining parameters in optimized shared library code generated
3464 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3465 not available''. GDB now correctly displays the variable's value.
3467 *** Changes in GDB 6.1:
3469 * Removed --with-mmalloc
3471 Support for the mmalloc memory manager has been removed, as it
3472 conflicted with the internal gdb byte cache.
3474 * Changes in AMD64 configurations
3476 The AMD64 target now includes the %cs and %ss registers. As a result
3477 the AMD64 remote protocol has changed; this affects the floating-point
3478 and SSE registers. If you rely on those registers for your debugging,
3479 you should upgrade gdbserver on the remote side.
3481 * Revised SPARC target
3483 The SPARC target has been completely revised, incorporating the
3484 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3485 support for LynxOS and SunOS 4 has been dropped. Calling functions
3486 from within GDB on operating systems with a non-executable stack
3487 (Solaris, OpenBSD) now works.
3491 GDB has a new C++ demangler which does a better job on the mangled
3492 names generated by current versions of g++. It also runs faster, so
3493 with this and other changes gdb should now start faster on large C++
3496 * DWARF 2 Location Expressions
3498 GDB support for location expressions has been extended to support function
3499 arguments and frame bases. Older versions of GDB could crash when they
3502 * C++ nested types and namespaces
3504 GDB's support for nested types and namespaces in C++ has been
3505 improved, especially if you use the DWARF 2 debugging format. (This
3506 is the default for recent versions of GCC on most platforms.)
3507 Specifically, if you have a class "Inner" defined within a class or
3508 namespace "Outer", then GDB realizes that the class's name is
3509 "Outer::Inner", not simply "Inner". This should greatly reduce the
3510 frequency of complaints about not finding RTTI symbols. In addition,
3511 if you are stopped at inside of a function defined within a namespace,
3512 GDB modifies its name lookup accordingly.
3514 * New native configurations
3516 NetBSD/amd64 x86_64-*-netbsd*
3517 OpenBSD/amd64 x86_64-*-openbsd*
3518 OpenBSD/alpha alpha*-*-openbsd*
3519 OpenBSD/sparc sparc-*-openbsd*
3520 OpenBSD/sparc64 sparc64-*-openbsd*
3522 * New debugging protocols
3524 M32R with SDI protocol m32r-*-elf*
3526 * "set prompt-escape-char" command deleted.
3528 The command "set prompt-escape-char" has been deleted. This command,
3529 and its very obscure effet on GDB's prompt, was never documented,
3530 tested, nor mentioned in the NEWS file.
3532 * OBSOLETE configurations and files
3534 Configurations that have been declared obsolete in this release have
3535 been commented out. Unless there is activity to revive these
3536 configurations, the next release of GDB will have their sources
3537 permanently REMOVED.
3539 Sun 3, running SunOS 3 m68*-*-sunos3*
3540 Sun 3, running SunOS 4 m68*-*-sunos4*
3541 Sun 2, running SunOS 3 m68000-*-sunos3*
3542 Sun 2, running SunOS 4 m68000-*-sunos4*
3543 Motorola 680x0 running LynxOS m68*-*-lynxos*
3544 AT&T 3b1/Unix pc m68*-att-*
3545 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3546 decstation mips-dec-* mips-little-*
3547 riscos mips-*-riscos* mips-*-sysv*
3548 sonymips mips-sony-*
3549 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3551 * REMOVED configurations and files
3553 SGI Irix-4.x mips-sgi-irix4 or iris4
3554 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3555 Z8000 simulator z8k-zilog-none or z8ksim
3556 Matsushita MN10200 w/simulator mn10200-*-*
3557 H8/500 simulator h8500-hitachi-hms or h8500hms
3558 HP/PA running BSD hppa*-*-bsd*
3559 HP/PA running OSF/1 hppa*-*-osf*
3560 HP/PA Pro target hppa*-*-pro*
3561 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3562 386BSD i[3456]86-*-bsd*
3563 Sequent family i[3456]86-sequent-sysv4*
3564 i[3456]86-sequent-sysv*
3565 i[3456]86-sequent-bsd*
3566 SPARC running LynxOS sparc-*-lynxos*
3567 SPARC running SunOS 4 sparc-*-sunos4*
3568 Tsqware Sparclet sparclet-*-*
3569 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3571 *** Changes in GDB 6.0:
3575 Support for debugging the Objective-C programming language has been
3576 integrated into GDB.
3578 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3580 DWARF 2's Call Frame Information makes available compiler generated
3581 information that more exactly describes the program's run-time stack.
3582 By using this information, GDB is able to provide more robust stack
3585 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3586 have been updated to use a new backtrace mechanism which includes
3587 DWARF 2 CFI support.
3591 GDB's remote protocol has been extended to include support for hosted
3592 file I/O (where the remote target uses GDB's file system). See GDB's
3593 remote protocol documentation for details.
3595 * All targets using the new architecture framework.
3597 All of GDB's targets have been updated to use the new internal
3598 architecture framework. The way is now open for future GDB releases
3599 to include cross-architecture native debugging support (i386 on amd64,
3602 * GNU/Linux's Thread Local Storage (TLS)
3604 GDB now includes support for for the GNU/Linux implementation of
3605 per-thread variables.
3607 * GNU/Linux's Native POSIX Thread Library (NPTL)
3609 GDB's thread code has been updated to work with either the new
3610 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3612 * Separate debug info.
3614 GDB, in conjunction with BINUTILS, now supports a mechanism for
3615 automatically loading debug information from a separate file. Instead
3616 of shipping full debug and non-debug versions of system libraries,
3617 system integrators can now instead ship just the stripped libraries
3618 and optional debug files.
3620 * DWARF 2 Location Expressions
3622 DWARF 2 Location Expressions allow the compiler to more completely
3623 describe the location of variables (even in optimized code) to the
3626 GDB now includes preliminary support for location expressions (support
3627 for DW_OP_piece is still missing).
3631 A number of long standing bugs that caused GDB to die while starting a
3632 Java application have been fixed. GDB's Java support is now
3633 considered "useable".
3635 * GNU/Linux support for fork, vfork, and exec.
3637 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3638 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3641 * GDB supports logging output to a file
3643 There are two new commands, "set logging" and "show logging", which can be
3644 used to capture GDB's output to a file.
3646 * The meaning of "detach" has changed for gdbserver
3648 The "detach" command will now resume the application, as documented. To
3649 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3652 * d10v, m68hc11 `regs' command deprecated
3654 The `info registers' command has been updated so that it displays the
3655 registers using a format identical to the old `regs' command.
3659 A new command, "maint set profile on/off", has been added. This command can
3660 be used to enable or disable profiling while running GDB, to profile a
3661 session or a set of commands. In addition there is a new configure switch,
3662 "--enable-profiling", which will cause GDB to be compiled with profiling
3663 data, for more informative profiling results.
3665 * Default MI syntax changed to "mi2".
3667 The default MI (machine interface) syntax, enabled by the command line
3668 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3669 "mi1", can be enabled by specifying the option "-i=mi1".
3671 Support for the original "mi0" syntax (included in GDB 5.0) has been
3674 Fix for gdb/192: removed extraneous space when displaying frame level.
3675 Fix for gdb/672: update changelist is now output in mi list format.
3676 Fix for gdb/702: a -var-assign that updates the value now shows up
3677 in a subsequent -var-update.
3679 * New native configurations.
3681 FreeBSD/amd64 x86_64-*-freebsd*
3683 * Multi-arched targets.
3685 HP/PA HPUX11 hppa*-*-hpux*
3686 Renesas M32R/D w/simulator m32r-*-elf*
3688 * OBSOLETE configurations and files
3690 Configurations that have been declared obsolete in this release have
3691 been commented out. Unless there is activity to revive these
3692 configurations, the next release of GDB will have their sources
3693 permanently REMOVED.
3695 Z8000 simulator z8k-zilog-none or z8ksim
3696 Matsushita MN10200 w/simulator mn10200-*-*
3697 H8/500 simulator h8500-hitachi-hms or h8500hms
3698 HP/PA running BSD hppa*-*-bsd*
3699 HP/PA running OSF/1 hppa*-*-osf*
3700 HP/PA Pro target hppa*-*-pro*
3701 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3702 Sequent family i[3456]86-sequent-sysv4*
3703 i[3456]86-sequent-sysv*
3704 i[3456]86-sequent-bsd*
3705 Tsqware Sparclet sparclet-*-*
3706 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3708 * REMOVED configurations and files
3711 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3712 IBM AIX PS/2 i[3456]86-*-aix
3713 i386 running Mach 3.0 i[3456]86-*-mach3*
3714 i386 running Mach i[3456]86-*-mach*
3715 i386 running OSF/1 i[3456]86-*osf1mk*
3716 HP/Apollo 68k Family m68*-apollo*-sysv*,
3718 m68*-hp-bsd*, m68*-hp-hpux*
3719 Argonaut Risc Chip (ARC) arc-*-*
3720 Mitsubishi D30V d30v-*-*
3721 Fujitsu FR30 fr30-*-elf*
3722 OS/9000 i[34]86-*-os9k
3723 I960 with MON960 i960-*-coff
3725 * MIPS $fp behavior changed
3727 The convenience variable $fp, for the MIPS, now consistently returns
3728 the address of the current frame's base. Previously, depending on the
3729 context, $fp could refer to either $sp or the current frame's base
3730 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3731 The GNU Source-Level Debugger''.
3733 *** Changes in GDB 5.3:
3735 * GNU/Linux shared library multi-threaded performance improved.
3737 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3738 `/proc', in preference to `ptrace' for memory reads. This may result
3739 in an improvement in the start-up time of multi-threaded, shared
3740 library applications when run under GDB. One GDB user writes: ``loads
3741 shared libs like mad''.
3743 * ``gdbserver'' now supports multi-threaded applications on some targets
3745 Support for debugging multi-threaded applications which use
3746 the GNU/Linux LinuxThreads package has been added for
3747 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3748 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3750 * GDB now supports C/C++ preprocessor macros.
3752 GDB now expands preprocessor macro invocations in C/C++ expressions,
3753 and provides various commands for showing macro definitions and how
3756 The new command `macro expand EXPRESSION' expands any macro
3757 invocations in expression, and shows the result.
3759 The new command `show macro MACRO-NAME' shows the definition of the
3760 macro named MACRO-NAME, and where it was defined.
3762 Most compilers don't include information about macros in the debugging
3763 information by default. In GCC 3.1, for example, you need to compile
3764 your program with the options `-gdwarf-2 -g3'. If the macro
3765 information is present in the executable, GDB will read it.
3767 * Multi-arched targets.
3769 DEC Alpha (partial) alpha*-*-*
3770 DEC VAX (partial) vax-*-*
3772 National Semiconductor NS32000 (partial) ns32k-*-*
3773 Motorola 68000 (partial) m68k-*-*
3774 Motorola MCORE mcore-*-*
3778 Fujitsu FRV architecture added by Red Hat frv*-*-*
3781 * New native configurations
3783 Alpha NetBSD alpha*-*-netbsd*
3784 SH NetBSD sh*-*-netbsdelf*
3785 MIPS NetBSD mips*-*-netbsd*
3786 UltraSPARC NetBSD sparc64-*-netbsd*
3788 * OBSOLETE configurations and files
3790 Configurations that have been declared obsolete in this release have
3791 been commented out. Unless there is activity to revive these
3792 configurations, the next release of GDB will have their sources
3793 permanently REMOVED.
3795 Mitsubishi D30V d30v-*-*
3796 OS/9000 i[34]86-*-os9k
3797 IBM AIX PS/2 i[3456]86-*-aix
3798 Fujitsu FR30 fr30-*-elf*
3799 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3800 Argonaut Risc Chip (ARC) arc-*-*
3801 i386 running Mach 3.0 i[3456]86-*-mach3*
3802 i386 running Mach i[3456]86-*-mach*
3803 i386 running OSF/1 i[3456]86-*osf1mk*
3804 HP/Apollo 68k Family m68*-apollo*-sysv*,
3806 m68*-hp-bsd*, m68*-hp-hpux*
3807 I960 with MON960 i960-*-coff
3809 * OBSOLETE languages
3811 CHILL, a Pascal like language used by telecommunications companies.
3813 * REMOVED configurations and files
3815 AMD 29k family via UDI a29k-amd-udi, udi29k
3816 A29K VxWorks a29k-*-vxworks
3817 AMD 29000 embedded, using EBMON a29k-none-none
3818 AMD 29000 embedded with COFF a29k-none-coff
3819 AMD 29000 embedded with a.out a29k-none-aout
3821 testsuite/gdb.hp/gdb.threads-hp/ directory
3823 * New command "set max-user-call-depth <nnn>"
3825 This command allows the user to limit the call depth of user-defined
3826 commands. The default is 1024.
3828 * Changes in FreeBSD/i386 native debugging.
3830 Support for the "generate-core-file" has been added.
3832 * New commands "dump", "append", and "restore".
3834 These commands allow data to be copied from target memory
3835 to a bfd-format or binary file (dump and append), and back
3836 from a file into memory (restore).
3838 * Improved "next/step" support on multi-processor Alpha Tru64.
3840 The previous single-step mechanism could cause unpredictable problems,
3841 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3842 of a software single-step mechanism prevents this.
3844 *** Changes in GDB 5.2.1:
3852 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3853 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3854 Fix, by Joel Brobecker imported from mainline.
3856 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3857 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3858 Fix, by Fred Fish, imported from mainline.
3860 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3861 Surprisingly enough, it works now.
3862 By Michal Ludvig, imported from mainline.
3864 i386 hardware watchpoint support:
3865 avoid misses on second run for some targets.
3866 By Pierre Muller, imported from mainline.
3868 *** Changes in GDB 5.2:
3870 * New command "set trust-readonly-sections on[off]".
3872 This command is a hint that tells gdb that read-only sections
3873 really are read-only (ie. that their contents will not change).
3874 In this mode, gdb will go to the object file rather than the
3875 target to read memory from read-only sections (such as ".text").
3876 This can be a significant performance improvement on some
3877 (notably embedded) targets.
3879 * New command "generate-core-file" (or "gcore").
3881 This new gdb command allows the user to drop a core file of the child
3882 process state at any time. So far it's been implemented only for
3883 GNU/Linux and Solaris, but should be relatively easily ported to other
3884 hosts. Argument is core file name (defaults to core.<pid>).
3886 * New command line option
3888 GDB now accepts --pid or -p followed by a process id.
3890 * Change in command line behavior -- corefiles vs. process ids.
3892 There is a subtle behavior in the way in which GDB handles
3893 command line arguments. The first non-flag argument is always
3894 a program to debug, but the second non-flag argument may either
3895 be a corefile or a process id. Previously, GDB would attempt to
3896 open the second argument as a corefile, and if that failed, would
3897 issue a superfluous error message and then attempt to attach it as
3898 a process. Now, if the second argument begins with a non-digit,
3899 it will be treated as a corefile. If it begins with a digit,
3900 GDB will attempt to attach it as a process, and if no such process
3901 is found, will then attempt to open it as a corefile.
3903 * Changes in ARM configurations.
3905 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3906 configuration is fully multi-arch.
3908 * New native configurations
3910 ARM NetBSD arm*-*-netbsd*
3911 x86 OpenBSD i[3456]86-*-openbsd*
3912 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3913 Sparc64 running FreeBSD sparc64-*-freebsd*
3917 Sanyo XStormy16 xstormy16-elf
3919 * OBSOLETE configurations and files
3921 Configurations that have been declared obsolete in this release have
3922 been commented out. Unless there is activity to revive these
3923 configurations, the next release of GDB will have their sources
3924 permanently REMOVED.
3926 AMD 29k family via UDI a29k-amd-udi, udi29k
3927 A29K VxWorks a29k-*-vxworks
3928 AMD 29000 embedded, using EBMON a29k-none-none
3929 AMD 29000 embedded with COFF a29k-none-coff
3930 AMD 29000 embedded with a.out a29k-none-aout
3932 testsuite/gdb.hp/gdb.threads-hp/ directory
3934 * REMOVED configurations and files
3936 TI TMS320C80 tic80-*-*
3938 PowerPC Solaris powerpcle-*-solaris*
3939 PowerPC Windows NT powerpcle-*-cygwin32
3940 PowerPC Netware powerpc-*-netware*
3941 Harris/CXUX m88k m88*-harris-cxux*
3942 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3943 ns32k-utek-sysv* ns32k-utek-*
3944 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3945 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3946 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3947 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3948 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3950 * Changes to command line processing
3952 The new `--args' feature can be used to specify command-line arguments
3953 for the inferior from gdb's command line.
3955 * Changes to key bindings
3957 There is a new `operate-and-get-next' function bound to `C-o'.
3959 *** Changes in GDB 5.1.1
3961 Fix compile problem on DJGPP.
3963 Fix a problem with floating-point registers on the i386 being
3966 Fix to stop GDB crashing on .debug_str debug info.
3968 Numerous documentation fixes.
3970 Numerous testsuite fixes.
3972 *** Changes in GDB 5.1:
3974 * New native configurations
3976 Alpha FreeBSD alpha*-*-freebsd*
3977 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3978 MIPS GNU/Linux mips*-*-linux*
3979 MIPS SGI Irix 6.x mips*-sgi-irix6*
3980 ia64 AIX ia64-*-aix*
3981 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3985 Motorola 68HC11 and 68HC12 m68hc11-elf
3987 UltraSparc running GNU/Linux sparc64-*-linux*
3989 * OBSOLETE configurations and files
3991 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3992 Harris/CXUX m88k m88*-harris-cxux*
3993 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3994 ns32k-utek-sysv* ns32k-utek-*
3995 TI TMS320C80 tic80-*-*
3997 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3998 PowerPC Solaris powerpcle-*-solaris*
3999 PowerPC Windows NT powerpcle-*-cygwin32
4000 PowerPC Netware powerpc-*-netware*
4001 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4002 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4003 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4004 Apple Macintosh (MPW) host N/A
4006 stuff.c (Program to stuff files into a specially prepared space in kdb)
4007 kdb-start.c (Main loop for the standalone kernel debugger)
4009 Configurations that have been declared obsolete in this release have
4010 been commented out. Unless there is activity to revive these
4011 configurations, the next release of GDB will have their sources
4012 permanently REMOVED.
4014 * REMOVED configurations and files
4016 Altos 3068 m68*-altos-*
4017 Convex c1-*-*, c2-*-*
4019 ARM RISCix arm-*-* (as host)
4023 * GDB has been converted to ISO C.
4025 GDB's source code has been converted to ISO C. In particular, the
4026 sources are fully protoized, and rely on standard headers being
4031 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4033 * The MI enabled by default.
4035 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4036 revised and enabled by default. Packages which use GDB as a debugging
4037 engine behind a UI or another front end are encouraged to switch to
4038 using the GDB/MI interface, instead of the old annotations interface
4039 which is now deprecated.
4041 * Support for debugging Pascal programs.
4043 GDB now includes support for debugging Pascal programs. The following
4044 main features are supported:
4046 - Pascal-specific data types such as sets;
4048 - automatic recognition of Pascal sources based on file-name
4051 - Pascal-style display of data types, variables, and functions;
4053 - a Pascal expression parser.
4055 However, some important features are not yet supported.
4057 - Pascal string operations are not supported at all;
4059 - there are some problems with boolean types;
4061 - Pascal type hexadecimal constants are not supported
4062 because they conflict with the internal variables format;
4064 - support for Pascal objects and classes is not full yet;
4066 - unlike Pascal, GDB is case-sensitive for symbol names.
4068 * Changes in completion.
4070 Commands such as `shell', `run' and `set args', which pass arguments
4071 to inferior programs, now complete on file names, similar to what
4072 users expect at the shell prompt.
4074 Commands which accept locations, such as `disassemble', `print',
4075 `breakpoint', `until', etc. now complete on filenames as well as
4076 program symbols. Thus, if you type "break foob TAB", and the source
4077 files linked into the programs include `foobar.c', that file name will
4078 be one of the candidates for completion. However, file names are not
4079 considered for completion after you typed a colon that delimits a file
4080 name from a name of a function in that file, as in "break foo.c:bar".
4082 `set demangle-style' completes on available demangling styles.
4084 * New platform-independent commands:
4086 It is now possible to define a post-hook for a command as well as a
4087 hook that runs before the command. For more details, see the
4088 documentation of `hookpost' in the GDB manual.
4090 * Changes in GNU/Linux native debugging.
4092 Support for debugging multi-threaded programs has been completely
4093 revised for all platforms except m68k and sparc. You can now debug as
4094 many threads as your system allows you to have.
4096 Attach/detach is supported for multi-threaded programs.
4098 Support for SSE registers was added for x86. This doesn't work for
4099 multi-threaded programs though.
4101 * Changes in MIPS configurations.
4103 Multi-arch support is enabled for all MIPS configurations.
4105 GDB can now be built as native debugger on SGI Irix 6.x systems for
4106 debugging n32 executables. (Debugging 64-bit executables is not yet
4109 * Unified support for hardware watchpoints in all x86 configurations.
4111 Most (if not all) native x86 configurations support hardware-assisted
4112 breakpoints and watchpoints in a unified manner. This support
4113 implements debug register sharing between watchpoints, which allows to
4114 put a virtually infinite number of watchpoints on the same address,
4115 and also supports watching regions up to 16 bytes with several debug
4118 The new maintenance command `maintenance show-debug-regs' toggles
4119 debugging print-outs in functions that insert, remove, and test
4120 watchpoints and hardware breakpoints.
4122 * Changes in the DJGPP native configuration.
4124 New command ``info dos sysinfo'' displays assorted information about
4125 the CPU, OS, memory, and DPMI server.
4127 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4128 display information about segment descriptors stored in GDT, LDT, and
4131 New commands ``info dos pde'' and ``info dos pte'' display entries
4132 from Page Directory and Page Tables (for now works with CWSDPMI only).
4133 New command ``info dos address-pte'' displays the Page Table entry for
4134 a given linear address.
4136 GDB can now pass command lines longer than 126 characters to the
4137 program being debugged (requires an update to the libdbg.a library
4138 which is part of the DJGPP development kit).
4140 DWARF2 debug info is now supported.
4142 It is now possible to `step' and `next' through calls to `longjmp'.
4144 * Changes in documentation.
4146 All GDB documentation was converted to GFDL, the GNU Free
4147 Documentation License.
4149 Tracepoints-related commands are now fully documented in the GDB
4152 TUI, the Text-mode User Interface, is now documented in the manual.
4154 Tracepoints-related commands are now fully documented in the GDB
4157 The "GDB Internals" manual now has an index. It also includes
4158 documentation of `ui_out' functions, GDB coding standards, x86
4159 hardware watchpoints, and memory region attributes.
4161 * GDB's version number moved to ``version.in''
4163 The Makefile variable VERSION has been replaced by the file
4164 ``version.in''. People creating GDB distributions should update the
4165 contents of this file.
4169 GUD support is now a standard part of the EMACS distribution.
4171 *** Changes in GDB 5.0:
4173 * Improved support for debugging FP programs on x86 targets
4175 Unified and much-improved support for debugging floating-point
4176 programs on all x86 targets. In particular, ``info float'' now
4177 displays the FP registers in the same format on all x86 targets, with
4178 greater level of detail.
4180 * Improvements and bugfixes in hardware-assisted watchpoints
4182 It is now possible to watch array elements, struct members, and
4183 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4184 on x86 targets no longer erroneously trigger when the address is
4187 * Improvements in the native DJGPP version of GDB
4189 The distribution now includes all the scripts and auxiliary files
4190 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4191 machines ``out of the box''.
4193 The DJGPP version can now debug programs that use signals. It is
4194 possible to catch signals that happened in the debuggee, deliver
4195 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4196 would kill the program being debugged.) Programs that hook hardware
4197 interrupts (keyboard, timer, etc.) can also be debugged.
4199 It is now possible to debug DJGPP programs that redirect their
4200 standard handles or switch them to raw (as opposed to cooked) mode, or
4201 even close them. The command ``run < foo > bar'' works as expected,
4202 and ``info terminal'' reports useful information about the debuggee's
4203 terminal, including raw/cooked mode, redirection, etc.
4205 The DJGPP version now uses termios functions for console I/O, which
4206 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4209 DOS-style file names with drive letters are now fully supported by
4212 It is now possible to debug DJGPP programs that switch their working
4213 directory. It is also possible to rerun the debuggee any number of
4214 times without restarting GDB; thus, you can use the same setup,
4215 breakpoints, etc. for many debugging sessions.
4217 * New native configurations
4219 ARM GNU/Linux arm*-*-linux*
4220 PowerPC GNU/Linux powerpc-*-linux*
4224 Motorola MCore mcore-*-*
4225 x86 VxWorks i[3456]86-*-vxworks*
4226 PowerPC VxWorks powerpc-*-vxworks*
4227 TI TMS320C80 tic80-*-*
4229 * OBSOLETE configurations
4231 Altos 3068 m68*-altos-*
4232 Convex c1-*-*, c2-*-*
4234 ARM RISCix arm-*-* (as host)
4237 Configurations that have been declared obsolete will be commented out,
4238 but the code will be left in place. If there is no activity to revive
4239 these configurations before the next release of GDB, the sources will
4240 be permanently REMOVED.
4242 * Gould support removed
4244 Support for the Gould PowerNode and NP1 has been removed.
4246 * New features for SVR4
4248 On SVR4 native platforms (such as Solaris), if you attach to a process
4249 without first loading a symbol file, GDB will now attempt to locate and
4250 load symbols from the running process's executable file.
4252 * Many C++ enhancements
4254 C++ support has been greatly improved. Overload resolution now works properly
4255 in almost all cases. RTTI support is on the way.
4257 * Remote targets can connect to a sub-program
4259 A popen(3) style serial-device has been added. This device starts a
4260 sub-process (such as a stand-alone simulator) and then communicates
4261 with that. The sub-program to run is specified using the syntax
4262 ``|<program> <args>'' vis:
4264 (gdb) set remotedebug 1
4265 (gdb) target extended-remote |mn10300-elf-sim program-args
4267 * MIPS 64 remote protocol
4269 A long standing bug in the mips64 remote protocol where by GDB
4270 expected certain 32 bit registers (ex SR) to be transfered as 32
4271 instead of 64 bits has been fixed.
4273 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4274 added to provide backward compatibility with older versions of GDB.
4276 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4278 The command ``set remotebinarydownload'' command has been replaced by
4279 ``set remote X-packet''. Other commands in ``set remote'' family
4280 include ``set remote P-packet''.
4282 * Breakpoint commands accept ranges.
4284 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4285 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4286 ``tracepoint passcount'' also accepts a range of tracepoints.
4288 * ``apropos'' command added.
4290 The ``apropos'' command searches through command names and
4291 documentation strings, printing out matches, making it much easier to
4292 try to find a command that does what you are looking for.
4296 A new machine oriented interface (MI) has been added to GDB. This
4297 interface is designed for debug environments running GDB as a separate
4298 process. This is part of the long term libGDB project. See the
4299 "GDB/MI" chapter of the GDB manual for further information. It can be
4300 enabled by configuring with:
4302 .../configure --enable-gdbmi
4304 *** Changes in GDB-4.18:
4306 * New native configurations
4308 HP-UX 10.20 hppa*-*-hpux10.20
4309 HP-UX 11.x hppa*-*-hpux11.0*
4310 M68K GNU/Linux m68*-*-linux*
4314 Fujitsu FR30 fr30-*-elf*
4315 Intel StrongARM strongarm-*-*
4316 Mitsubishi D30V d30v-*-*
4318 * OBSOLETE configurations
4320 Gould PowerNode, NP1 np1-*-*, pn-*-*
4322 Configurations that have been declared obsolete will be commented out,
4323 but the code will be left in place. If there is no activity to revive
4324 these configurations before the next release of GDB, the sources will
4325 be permanently REMOVED.
4329 As a compatibility experiment, GDB's source files buildsym.h and
4330 buildsym.c have been converted to pure standard C, no longer
4331 containing any K&R compatibility code. We believe that all systems in
4332 use today either come with a standard C compiler, or have a GCC port
4333 available. If this is not true, please report the affected
4334 configuration to bug-gdb@gnu.org immediately. See the README file for
4335 information about getting a standard C compiler if you don't have one
4340 GDB now uses readline 2.2.
4342 * set extension-language
4344 You can now control the mapping between filename extensions and source
4345 languages by using the `set extension-language' command. For instance,
4346 you can ask GDB to treat .c files as C++ by saying
4347 set extension-language .c c++
4348 The command `info extensions' lists all of the recognized extensions
4349 and their associated languages.
4351 * Setting processor type for PowerPC and RS/6000
4353 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4354 you can use the `set processor' command to specify what variant of the
4355 PowerPC family you are debugging. The command
4359 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4360 following PowerPC and RS6000 variants:
4362 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4363 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4365 403GC IBM PowerPC 403GC
4366 505 Motorola PowerPC 505
4367 860 Motorola PowerPC 860 or 850
4368 601 Motorola PowerPC 601
4369 602 Motorola PowerPC 602
4370 603 Motorola/IBM PowerPC 603 or 603e
4371 604 Motorola PowerPC 604 or 604e
4372 750 Motorola/IBM PowerPC 750 or 750
4374 At the moment, this command just tells GDB what to name the
4375 special-purpose processor registers. Since almost all the affected
4376 registers are inaccessible to user-level programs, this command is
4377 only useful for remote debugging in its present form.
4381 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4382 more extensive support for HP-UX. Added features include shared
4383 library support, kernel threads and hardware watchpoints for 11.00,
4384 support for HP's ANSI C and C++ compilers, and a compatibility mode
4385 for xdb and dbx commands.
4389 HP's donation includes the new concept of catchpoints, which is a
4390 generalization of the old catch command. On HP-UX, it is now possible
4391 to catch exec, fork, and vfork, as well as library loading.
4393 This means that the existing catch command has changed; its first
4394 argument now specifies the type of catch to be set up. See the
4395 output of "help catch" for a list of catchpoint types.
4397 * Debugging across forks
4399 On HP-UX, you can choose which process to debug when a fork() happens
4404 HP has donated a curses-based terminal user interface (TUI). To get
4405 it, build with --enable-tui. Although this can be enabled for any
4406 configuration, at present it only works for native HP debugging.
4408 * GDB remote protocol additions
4410 A new protocol packet 'X' that writes binary data is now available.
4411 Default behavior is to try 'X', then drop back to 'M' if the stub
4412 fails to respond. The settable variable `remotebinarydownload'
4413 allows explicit control over the use of 'X'.
4415 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4416 full 64-bit address. The command
4418 set remoteaddresssize 32
4420 can be used to revert to the old behaviour. For existing remote stubs
4421 the change should not be noticed, as the additional address information
4424 In order to assist in debugging stubs, you may use the maintenance
4425 command `packet' to send any text string to the stub. For instance,
4427 maint packet heythere
4429 sends the packet "$heythere#<checksum>". Note that it is very easy to
4430 disrupt a debugging session by sending the wrong packet at the wrong
4433 The compare-sections command allows you to compare section data on the
4434 target to what is in the executable file without uploading or
4435 downloading, by comparing CRC checksums.
4437 * Tracing can collect general expressions
4439 You may now collect general expressions at tracepoints. This requires
4440 further additions to the target-side stub; see tracepoint.c and
4441 doc/agentexpr.texi for further details.
4443 * mask-address variable for Mips
4445 For Mips targets, you may control the zeroing of the upper 32 bits of
4446 a 64-bit address by entering `set mask-address on'. This is mainly
4447 of interest to users of embedded R4xxx and R5xxx processors.
4449 * Higher serial baud rates
4451 GDB's serial code now allows you to specify baud rates 57600, 115200,
4452 230400, and 460800 baud. (Note that your host system may not be able
4453 to achieve all of these rates.)
4457 The i960 configuration now includes an initial implementation of a
4458 builtin simulator, contributed by Jim Wilson.
4461 *** Changes in GDB-4.17:
4463 * New native configurations
4465 Alpha GNU/Linux alpha*-*-linux*
4466 Unixware 2.x i[3456]86-unixware2*
4467 Irix 6.x mips*-sgi-irix6*
4468 PowerPC GNU/Linux powerpc-*-linux*
4469 PowerPC Solaris powerpcle-*-solaris*
4470 Sparc GNU/Linux sparc-*-linux*
4471 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4475 Argonaut Risc Chip (ARC) arc-*-*
4476 Hitachi H8/300S h8300*-*-*
4477 Matsushita MN10200 w/simulator mn10200-*-*
4478 Matsushita MN10300 w/simulator mn10300-*-*
4479 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4480 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4481 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4482 Mitsubishi D10V w/simulator d10v-*-*
4483 Mitsubishi M32R/D w/simulator m32r-*-elf*
4484 Tsqware Sparclet sparclet-*-*
4485 NEC V850 w/simulator v850-*-*
4487 * New debugging protocols
4489 ARM with RDI protocol arm*-*-*
4490 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4491 DDB and LSI variants of PMON protocol mips*-*-*
4492 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4493 PowerPC with SDS protocol powerpc{,le}-*-eabi
4494 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4498 All configurations can now understand and use the DWARF 2 debugging
4499 format. The choice is automatic, if the symbol file contains DWARF 2
4504 GDB now includes basic Java language support. This support is
4505 only useful with Java compilers that produce native machine code.
4507 * solib-absolute-prefix and solib-search-path
4509 For SunOS and SVR4 shared libraries, you may now set the prefix for
4510 loading absolute shared library symbol files, and the search path for
4511 locating non-absolute shared library symbol files.
4513 * Live range splitting
4515 GDB can now effectively debug code for which GCC has performed live
4516 range splitting as part of its optimization. See gdb/doc/LRS for
4517 more details on the expected format of the stabs information.
4521 GDB's support for the GNU Hurd, including thread debugging, has been
4522 updated to work with current versions of the Hurd.
4526 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4527 instruction set. ARM GDB automatically detects when Thumb
4528 instructions are in use, and adjusts disassembly and backtracing
4533 GDB's MIPS target configurations now handle the MIP16 16-bit
4538 GDB now includes support for overlays; if an executable has been
4539 linked such that multiple sections are based at the same address, GDB
4540 will decide which section to use for symbolic info. You can choose to
4541 control the decision manually, using overlay commands, or implement
4542 additional target-side support and use "overlay load-target" to bring
4543 in the overlay mapping. Do "help overlay" for more detail.
4547 The command "info symbol <address>" displays information about
4548 the symbol at the specified address.
4552 The standard remote protocol now includes an extension that allows
4553 asynchronous collection and display of trace data. This requires
4554 extensive support in the target-side debugging stub. Tracing mode
4555 includes a new interaction mode in GDB and new commands: see the
4556 file tracepoint.c for more details.
4560 Configurations for embedded MIPS now include a simulator contributed
4561 by Cygnus Solutions. The simulator supports the instruction sets
4562 of most MIPS variants.
4566 Sparc configurations may now include the ERC32 simulator contributed
4567 by the European Space Agency. The simulator is not built into
4568 Sparc targets by default; configure with --enable-sim to include it.
4572 For target configurations that may include multiple variants of a
4573 basic architecture (such as MIPS and SH), you may now set the
4574 architecture explicitly. "set arch" sets, "info arch" lists
4575 the possible architectures.
4577 *** Changes in GDB-4.16:
4579 * New native configurations
4581 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4582 M68K NetBSD m68k-*-netbsd*
4583 PowerPC AIX 4.x powerpc-*-aix*
4584 PowerPC MacOS powerpc-*-macos*
4585 PowerPC Windows NT powerpcle-*-cygwin32
4586 RS/6000 AIX 4.x rs6000-*-aix4*
4590 ARM with RDP protocol arm-*-*
4591 I960 with MON960 i960-*-coff
4592 MIPS VxWorks mips*-*-vxworks*
4593 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4594 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4596 Matra Sparclet sparclet-*-*
4600 The powerpc-eabi configuration now includes the PSIM simulator,
4601 contributed by Andrew Cagney, with assistance from Mike Meissner.
4602 PSIM is a very elaborate model of the PowerPC, including not only
4603 basic instruction set execution, but also details of execution unit
4604 performance and I/O hardware. See sim/ppc/README for more details.
4608 GDB now works with Solaris 2.5.
4610 * Windows 95/NT native
4612 GDB will now work as a native debugger on Windows 95 and Windows NT.
4613 To build it from source, you must use the "gnu-win32" environment,
4614 which uses a DLL to emulate enough of Unix to run the GNU tools.
4615 Further information, binaries, and sources are available at
4616 ftp.cygnus.com, under pub/gnu-win32.
4618 * dont-repeat command
4620 If a user-defined command includes the command `dont-repeat', then the
4621 command will not be repeated if the user just types return. This is
4622 useful if the command is time-consuming to run, so that accidental
4623 extra keystrokes don't run the same command many times.
4625 * Send break instead of ^C
4627 The standard remote protocol now includes an option to send a break
4628 rather than a ^C to the target in order to interrupt it. By default,
4629 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4631 * Remote protocol timeout
4633 The standard remote protocol includes a new variable `remotetimeout'
4634 that allows you to set the number of seconds before GDB gives up trying
4635 to read from the target. The default value is 2.
4637 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4639 By default GDB will automatically keep track of objects as they are
4640 loaded and unloaded by the dynamic linker. By using the command `set
4641 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4642 when shared library events occur, thus allowing you to set breakpoints
4643 in shared libraries which are explicitly loaded by the inferior.
4645 Note this feature does not work on hpux8. On hpux9 you must link
4646 /usr/lib/end.o into your program. This feature should work
4647 automatically on hpux10.
4649 * Irix 5.x hardware watchpoint support
4651 Irix 5 configurations now support the use of hardware watchpoints.
4653 * Mips protocol "SYN garbage limit"
4655 When debugging a Mips target using the `target mips' protocol, you
4656 may set the number of characters that GDB will ignore by setting
4657 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4658 every character. The default value is 1050.
4660 * Recording and replaying remote debug sessions
4662 If you set `remotelogfile' to the name of a file, gdb will write to it
4663 a recording of a remote debug session. This recording may then be
4664 replayed back to gdb using "gdbreplay". See gdbserver/README for
4665 details. This is useful when you have a problem with GDB while doing
4666 remote debugging; you can make a recording of the session and send it
4667 to someone else, who can then recreate the problem.
4669 * Speedups for remote debugging
4671 GDB includes speedups for downloading and stepping MIPS systems using
4672 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4673 and more efficient S-record downloading.
4675 * Memory use reductions and statistics collection
4677 GDB now uses less memory and reports statistics about memory usage.
4678 Try the `maint print statistics' command, for example.
4680 *** Changes in GDB-4.15:
4682 * Psymtabs for XCOFF
4684 The symbol reader for AIX GDB now uses partial symbol tables. This
4685 can greatly improve startup time, especially for large executables.
4687 * Remote targets use caching
4689 Remote targets now use a data cache to speed up communication with the
4690 remote side. The data cache could lead to incorrect results because
4691 it doesn't know about volatile variables, thus making it impossible to
4692 debug targets which use memory mapped I/O devices. `set remotecache
4693 off' turns the the data cache off.
4695 * Remote targets may have threads
4697 The standard remote protocol now includes support for multiple threads
4698 in the target system, using new protocol commands 'H' and 'T'. See
4699 gdb/remote.c for details.
4703 If GDB is configured with `--enable-netrom', then it will include
4704 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4705 acts as though it is a bank of ROM on the target board, but you can
4706 write into it over the network. GDB's support consists only of
4707 support for fast loading into the emulated ROM; to debug, you must use
4708 another protocol, such as standard remote protocol. The usual
4709 sequence is something like
4711 target nrom <netrom-hostname>
4713 target remote <netrom-hostname>:1235
4717 GDB now includes support for the Apple Macintosh, as a host only. It
4718 may be run as either an MPW tool or as a standalone application, and
4719 it can debug through the serial port. All the usual GDB commands are
4720 available, but to the target command, you must supply "serial" as the
4721 device type instead of "/dev/ttyXX". See mpw-README in the main
4722 directory for more information on how to build. The MPW configuration
4723 scripts */mpw-config.in support only a few targets, and only the
4724 mips-idt-ecoff target has been tested.
4728 GDB configuration now uses autoconf. This is not user-visible,
4729 but does simplify configuration and building.
4733 GDB now supports hpux10.
4735 *** Changes in GDB-4.14:
4737 * New native configurations
4739 x86 FreeBSD i[345]86-*-freebsd
4740 x86 NetBSD i[345]86-*-netbsd
4741 NS32k NetBSD ns32k-*-netbsd
4742 Sparc NetBSD sparc-*-netbsd
4746 A29K VxWorks a29k-*-vxworks
4747 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4748 CPU32 EST-300 emulator m68*-*-est*
4749 PowerPC ELF powerpc-*-elf
4752 * Alpha OSF/1 support for procfs
4754 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4755 possible to attach to running processes. As the mounting of the /proc
4756 filesystem is optional on the Alpha, GDB automatically determines
4757 the availability of /proc during startup. This can lead to problems
4758 if /proc is unmounted after GDB has been started.
4760 * Arguments to user-defined commands
4762 User commands may accept up to 10 arguments separated by whitespace.
4763 Arguments are accessed within the user command via $arg0..$arg9. A
4766 print $arg0 + $arg1 + $arg2
4768 To execute the command use:
4771 Defines the command "adder" which prints the sum of its three arguments.
4772 Note the arguments are text substitutions, so they may reference variables,
4773 use complex expressions, or even perform inferior function calls.
4775 * New `if' and `while' commands
4777 This makes it possible to write more sophisticated user-defined
4778 commands. Both commands take a single argument, which is the
4779 expression to evaluate, and must be followed by the commands to
4780 execute, one per line, if the expression is nonzero, the list being
4781 terminated by the word `end'. The `if' command list may include an
4782 `else' word, which causes the following commands to be executed only
4783 if the expression is zero.
4785 * Fortran source language mode
4787 GDB now includes partial support for Fortran 77. It will recognize
4788 Fortran programs and can evaluate a subset of Fortran expressions, but
4789 variables and functions may not be handled correctly. GDB will work
4790 with G77, but does not yet know much about symbols emitted by other
4793 * Better HPUX support
4795 Most debugging facilities now work on dynamic executables for HPPAs
4796 running hpux9 or later. You can attach to running dynamically linked
4797 processes, but by default the dynamic libraries will be read-only, so
4798 for instance you won't be able to put breakpoints in them. To change
4799 that behavior do the following before running the program:
4805 This will cause the libraries to be mapped private and read-write.
4806 To revert to the normal behavior, do this:
4812 You cannot set breakpoints or examine data in the library until after
4813 the library is loaded if the function/data symbols do not have
4816 GDB can now also read debug symbols produced by the HP C compiler on
4817 HPPAs (sorry, no C++, Fortran or 68k support).
4819 * Target byte order now dynamically selectable
4821 You can choose which byte order to use with a target system, via the
4822 commands "set endian big" and "set endian little", and you can see the
4823 current setting by using "show endian". You can also give the command
4824 "set endian auto", in which case GDB will use the byte order
4825 associated with the executable. Currently, only embedded MIPS
4826 configurations support dynamic selection of target byte order.
4828 * New DOS host serial code
4830 This version uses DPMI interrupts to handle buffered I/O, so you
4831 no longer need to run asynctsr when debugging boards connected to
4834 *** Changes in GDB-4.13:
4836 * New "complete" command
4838 This lists all the possible completions for the rest of the line, if it
4839 were to be given as a command itself. This is intended for use by emacs.
4841 * Trailing space optional in prompt
4843 "set prompt" no longer adds a space for you after the prompt you set. This
4844 allows you to set a prompt which ends in a space or one that does not.
4846 * Breakpoint hit counts
4848 "info break" now displays a count of the number of times the breakpoint
4849 has been hit. This is especially useful in conjunction with "ignore"; you
4850 can ignore a large number of breakpoint hits, look at the breakpoint info
4851 to see how many times the breakpoint was hit, then run again, ignoring one
4852 less than that number, and this will get you quickly to the last hit of
4855 * Ability to stop printing at NULL character
4857 "set print null-stop" will cause GDB to stop printing the characters of
4858 an array when the first NULL is encountered. This is useful when large
4859 arrays actually contain only short strings.
4861 * Shared library breakpoints
4863 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4864 breakpoints in shared libraries before the executable is run.
4866 * Hardware watchpoints
4868 There is a new hardware breakpoint for the watch command for sparclite
4869 targets. See gdb/sparclite/hw_breakpoint.note.
4871 Hardware watchpoints are also now supported under GNU/Linux.
4875 Annotations have been added. These are for use with graphical interfaces,
4876 and are still experimental. Currently only gdba.el uses these.
4878 * Improved Irix 5 support
4880 GDB now works properly with Irix 5.2.
4882 * Improved HPPA support
4884 GDB now works properly with the latest GCC and GAS.
4886 * New native configurations
4888 Sequent PTX4 i[34]86-sequent-ptx4
4889 HPPA running OSF/1 hppa*-*-osf*
4890 Atari TT running SVR4 m68*-*-sysv4*
4891 RS/6000 LynxOS rs6000-*-lynxos*
4895 OS/9000 i[34]86-*-os9k
4896 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4899 * Hitachi SH7000 and E7000-PC ICE support
4901 There is now support for communicating with the Hitachi E7000-PC ICE.
4902 This is available automatically when GDB is configured for the SH.
4906 As usual, a variety of small fixes and improvements, both generic
4907 and configuration-specific. See the ChangeLog for more detail.
4909 *** Changes in GDB-4.12:
4911 * Irix 5 is now supported
4915 GDB-4.12 on the HPPA has a number of changes which make it unable
4916 to debug the output from the currently released versions of GCC and
4917 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4918 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4919 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4922 *** Changes in GDB-4.11:
4924 * User visible changes:
4928 The "set remotedebug" option is now consistent between the mips remote
4929 target, remote targets using the gdb-specific protocol, UDI (AMD's
4930 debug protocol for the 29k) and the 88k bug monitor. It is now an
4931 integer specifying a debug level (normally 0 or 1, but 2 means more
4932 debugging info for the mips target).
4934 * DEC Alpha native support
4936 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4937 debug info, but GDB works fairly well with the DEC compiler and should
4938 work with a future GCC release. See the README file for a few
4939 Alpha-specific notes.
4941 * Preliminary thread implementation
4943 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4945 * LynxOS native and target support for 386
4947 This release has been hosted on LynxOS 2.2, and also can be configured
4948 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4951 * Improvements in C++ mangling/demangling.
4953 This release has much better g++ debugging, specifically in name
4954 mangling/demangling, virtual function calls, print virtual table,
4955 call methods, ...etc.
4957 *** Changes in GDB-4.10:
4959 * User visible changes:
4961 Remote debugging using the GDB-specific (`target remote') protocol now
4962 supports the `load' command. This is only useful if you have some
4963 other way of getting the stub to the target system, and you can put it
4964 somewhere in memory where it won't get clobbered by the download.
4966 Filename completion now works.
4968 When run under emacs mode, the "info line" command now causes the
4969 arrow to point to the line specified. Also, "info line" prints
4970 addresses in symbolic form (as well as hex).
4972 All vxworks based targets now support a user settable option, called
4973 vxworks-timeout. This option represents the number of seconds gdb
4974 should wait for responses to rpc's. You might want to use this if
4975 your vxworks target is, perhaps, a slow software simulator or happens
4976 to be on the far side of a thin network line.
4980 This release contains support for using a DEC alpha as a GDB host for
4981 cross debugging. Native alpha debugging is not supported yet.
4984 *** Changes in GDB-4.9:
4988 This is the first GDB release which is accompanied by a matching testsuite.
4989 The testsuite requires installation of dejagnu, which should be available
4990 via ftp from most sites that carry GNU software.
4994 'Cfront' style demangling has had its name changed to 'ARM' style, to
4995 emphasize that it was written from the specifications in the C++ Annotated
4996 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4997 disclaimers, it still generated too much confusion with users attempting to
4998 use gdb with AT&T cfront.
5002 GDB now uses a standard remote interface to a simulator library.
5003 So far, the library contains simulators for the Zilog Z8001/2, the
5004 Hitachi H8/300, H8/500 and Super-H.
5006 * New targets supported
5008 H8/300 simulator h8300-hitachi-hms or h8300hms
5009 H8/500 simulator h8500-hitachi-hms or h8500hms
5010 SH simulator sh-hitachi-hms or sh
5011 Z8000 simulator z8k-zilog-none or z8ksim
5012 IDT MIPS board over serial line mips-idt-ecoff
5014 Cross-debugging to GO32 targets is supported. It requires a custom
5015 version of the i386-stub.c module which is integrated with the
5016 GO32 memory extender.
5018 * New remote protocols
5020 MIPS remote debugging protocol.
5022 * New source languages supported
5024 This version includes preliminary support for Chill, a Pascal like language
5025 used by telecommunications companies. Chill support is also being integrated
5026 into the GNU compiler, but we don't know when it will be publically available.
5029 *** Changes in GDB-4.8:
5031 * HP Precision Architecture supported
5033 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5034 version of this support was available as a set of patches from the
5035 University of Utah. GDB does not support debugging of programs
5036 compiled with the HP compiler, because HP will not document their file
5037 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5038 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5040 Many problems in the preliminary version have been fixed.
5042 * Faster and better demangling
5044 We have improved template demangling and fixed numerous bugs in the GNU style
5045 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5046 character types (wchar_t) are now supported. Demangling of each symbol is now
5047 only done once, and is cached when the symbol table for a file is read in.
5048 This results in a small increase in memory usage for C programs, a moderate
5049 increase in memory usage for C++ programs, and a fantastic speedup in
5052 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5053 from the specifications in the Annotated Reference Manual, which AT&T's
5054 compiler does not actually implement.
5056 * G++ multiple inheritance compiler problem
5058 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5059 inheritance lattices was reworked to properly discover ambiguities. We
5060 recently found an example which causes this new algorithm to fail in a
5061 very subtle way, producing bad debug information for those classes.
5062 The file 'gcc.patch' (in this directory) can be applied to gcc to
5063 circumvent the problem. A future GCC release will contain a complete
5066 The previous G++ debug info problem (mentioned below for the gdb-4.7
5067 release) is fixed in gcc version 2.3.2.
5069 * Improved configure script
5071 The `configure' script will now attempt to guess your system type if
5072 you don't supply a host system type. The old scheme of supplying a
5073 host system triplet is preferable over using this. All the magic is
5074 done in the new `config.guess' script. Examine it for details.
5076 We have also brought our configure script much more in line with the FSF's
5077 version. It now supports the --with-xxx options. In particular,
5078 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5079 The resulting GDB will not be able to read arbitrary object file formats --
5080 only the format ``expected'' to be used on the configured target system.
5081 We hope to make this the default in a future release.
5083 * Documentation improvements
5085 There's new internal documentation on how to modify GDB, and how to
5086 produce clean changes to the code. We implore people to read it
5087 before submitting changes.
5089 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5090 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5091 `info' files are also provided. To build `info' files from scratch,
5092 you will need the latest `makeinfo' release, which will be available in
5093 a future texinfo-X.Y release.
5095 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5096 We're not sure exactly which versions have this problem, but it has
5097 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5098 or better. If that isn't possible, there is a patch in
5099 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5100 around this problem.
5104 GDB now supports array constants that can be used in expressions typed in by
5105 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5106 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5109 The new directory `gdb/sparclite' contains a program that demonstrates
5110 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5112 * New native hosts supported
5114 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5115 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5117 * New targets supported
5119 AMD 29k family via UDI a29k-amd-udi or udi29k
5121 * New file formats supported
5123 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5124 HPUX core files, and SCO 3.2v2 core files.
5128 Attaching to processes now works again; thanks for the many bug reports.
5130 We have also stomped on a bunch of core dumps caused by
5131 printf_filtered("%s") problems.
5133 We eliminated a copyright problem on the rpc and ptrace header files
5134 for VxWorks, which was discovered at the last minute during the 4.7
5135 release. You should now be able to build a VxWorks GDB.
5137 You can now interrupt gdb while an attached process is running. This
5138 will cause the attached process to stop, and give control back to GDB.
5140 We fixed problems caused by using too many file descriptors
5141 for reading symbols from object files and libraries. This was
5142 especially a problem for programs that used many (~100) shared
5145 The `step' command now only enters a subroutine if there is line number
5146 information for the subroutine. Otherwise it acts like the `next'
5147 command. Previously, `step' would enter subroutines if there was
5148 any debugging information about the routine. This avoids problems
5149 when using `cc -g1' on MIPS machines.
5151 * Internal improvements
5153 GDB's internal interfaces have been improved to make it easier to support
5154 debugging of multiple languages in the future.
5156 GDB now uses a common structure for symbol information internally.
5157 Minimal symbols (derived from linkage symbols in object files), partial
5158 symbols (from a quick scan of debug information), and full symbols
5159 contain a common subset of information, making it easier to write
5160 shared code that handles any of them.
5162 * New command line options
5164 We now accept --silent as an alias for --quiet.
5168 The memory-mapped-malloc library is now licensed under the GNU Library
5169 General Public License.
5171 *** Changes in GDB-4.7:
5173 * Host/native/target split
5175 GDB has had some major internal surgery to untangle the support for
5176 hosts and remote targets. Now, when you configure GDB for a remote
5177 target, it will no longer load in all of the support for debugging
5178 local programs on the host. When fully completed and tested, this will
5179 ensure that arbitrary host/target combinations are possible.
5181 The primary conceptual shift is to separate the non-portable code in
5182 GDB into three categories. Host specific code is required any time GDB
5183 is compiled on that host, regardless of the target. Target specific
5184 code relates to the peculiarities of the target, but can be compiled on
5185 any host. Native specific code is everything else: it can only be
5186 built when the host and target are the same system. Child process
5187 handling and core file support are two common `native' examples.
5189 GDB's use of /proc for controlling Unix child processes is now cleaner.
5190 It has been split out into a single module under the `target_ops' vector,
5191 plus two native-dependent functions for each system that uses /proc.
5193 * New hosts supported
5195 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5196 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5197 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5199 * New targets supported
5201 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5202 68030 and CPU32 m68030-*-*, m68332-*-*
5204 * New native hosts supported
5206 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5207 (386bsd is not well tested yet)
5208 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5210 * New file formats supported
5212 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5213 supports reading of `a.out.adobe' object files, which are an a.out
5214 format extended with minimal information about multiple sections.
5218 `show copying' is the same as the old `info copying'.
5219 `show warranty' is the same as `info warrantee'.
5220 These were renamed for consistency. The old commands continue to work.
5222 `info handle' is a new alias for `info signals'.
5224 You can now define pre-command hooks, which attach arbitrary command
5225 scripts to any command. The commands in the hook will be executed
5226 prior to the user's command. You can also create a hook which will be
5227 executed whenever the program stops. See gdb.texinfo.
5231 We now deal with Cfront style name mangling, and can even extract type
5232 info from mangled symbols. GDB can automatically figure out which
5233 symbol mangling style your C++ compiler uses.
5235 Calling of methods and virtual functions has been improved as well.
5239 The crash that occured when debugging Sun Ansi-C compiled binaries is
5240 fixed. This was due to mishandling of the extra N_SO stabs output
5243 We also finally got Ultrix 4.2 running in house, and fixed core file
5244 support, with help from a dozen people on the net.
5246 John M. Farrell discovered that the reason that single-stepping was so
5247 slow on all of the Mips based platforms (primarily SGI and DEC) was
5248 that we were trying to demangle and lookup a symbol used for internal
5249 purposes on every instruction that was being stepped through. Changing
5250 the name of that symbol so that it couldn't be mistaken for a C++
5251 mangled symbol sped things up a great deal.
5253 Rich Pixley sped up symbol lookups in general by getting much smarter
5254 about when C++ symbol mangling is necessary. This should make symbol
5255 completion (TAB on the command line) much faster. It's not as fast as
5256 we'd like, but it's significantly faster than gdb-4.6.
5260 A new user controllable variable 'call_scratch_address' can
5261 specify the location of a scratch area to be used when GDB
5262 calls a function in the target. This is necessary because the
5263 usual method of putting the scratch area on the stack does not work
5264 in systems that have separate instruction and data spaces.
5266 We integrated changes to support the 29k UDI (Universal Debugger
5267 Interface), but discovered at the last minute that we didn't have all
5268 of the appropriate copyright paperwork. We are working with AMD to
5269 resolve this, and hope to have it available soon.
5273 We have sped up the remote serial line protocol, especially for targets
5274 with lots of registers. It now supports a new `expedited status' ('T')
5275 message which can be used in place of the existing 'S' status message.
5276 This allows the remote stub to send only the registers that GDB
5277 needs to make a quick decision about single-stepping or conditional
5278 breakpoints, eliminating the need to fetch the entire register set for
5279 each instruction being stepped through.
5281 The GDB remote serial protocol now implements a write-through cache for
5282 registers, only re-reading the registers if the target has run.
5284 There is also a new remote serial stub for SPARC processors. You can
5285 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5286 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5287 processor with a serial port.
5291 Configure.in files have become much easier to read and modify. A new
5292 `table driven' format makes it more obvious what configurations are
5293 supported, and what files each one uses.
5297 There is a new opcodes library which will eventually contain all of the
5298 disassembly routines and opcode tables. At present, it only contains
5299 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5300 disassembler (binutils/objdump) to share these routines.
5302 The libiberty library is now copylefted under the GNU Library General
5303 Public License. This allows more liberal use, and was done so libg++
5304 can use it. This makes no difference to GDB, since the Library License
5305 grants all the rights from the General Public License.
5309 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5310 reference to the stabs symbol info used by the debugger. It is (as far
5311 as we know) the only published document on this fascinating topic. We
5312 encourage you to read it, compare it to the stabs information on your
5313 system, and send improvements on the document in general (to
5314 bug-gdb@prep.ai.mit.edu).
5316 And, of course, many bugs have been fixed.
5319 *** Changes in GDB-4.6:
5321 * Better support for C++ function names
5323 GDB now accepts as input the "demangled form" of C++ overloaded function
5324 names and member function names, and can do command completion on such names
5325 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5326 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5327 Make use of command completion, it is your friend.
5329 GDB also now accepts a variety of C++ mangled symbol formats. They are
5330 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5331 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5332 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5333 for the list of formats.
5335 * G++ symbol mangling problem
5337 Recent versions of gcc have a bug in how they emit debugging information for
5338 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5339 directory) can be applied to gcc to fix the problem. Alternatively, if you
5340 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5341 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5342 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5345 * New 'maintenance' command
5347 All of the commands related to hacking GDB internals have been moved out of
5348 the main command set, and now live behind the 'maintenance' command. This
5349 can also be abbreviated as 'mt'. The following changes were made:
5351 dump-me -> maintenance dump-me
5352 info all-breakpoints -> maintenance info breakpoints
5353 printmsyms -> maintenance print msyms
5354 printobjfiles -> maintenance print objfiles
5355 printpsyms -> maintenance print psymbols
5356 printsyms -> maintenance print symbols
5358 The following commands are new:
5360 maintenance demangle Call internal GDB demangler routine to
5361 demangle a C++ link name and prints the result.
5362 maintenance print type Print a type chain for a given symbol
5364 * Change to .gdbinit file processing
5366 We now read the $HOME/.gdbinit file before processing the argv arguments
5367 (e.g. reading symbol files or core files). This allows global parameters to
5368 be set, which will apply during the symbol reading. The ./.gdbinit is still
5369 read after argv processing.
5371 * New hosts supported
5373 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5375 GNU/Linux support i386-unknown-linux or linux
5377 We are also including code to support the HP/PA running BSD and HPUX. This
5378 is almost guaranteed not to work, as we didn't have time to test or build it
5379 for this release. We are including it so that the more adventurous (or
5380 masochistic) of you can play with it. We also had major problems with the
5381 fact that the compiler that we got from HP doesn't support the -g option.
5384 * New targets supported
5386 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5388 * More smarts about finding #include files
5390 GDB now remembers the compilation directory for all include files, and for
5391 all files from which C is generated (like yacc and lex sources). This
5392 greatly improves GDB's ability to find yacc/lex sources, and include files,
5393 especially if you are debugging your program from a directory different from
5394 the one that contains your sources.
5396 We also fixed a bug which caused difficulty with listing and setting
5397 breakpoints in include files which contain C code. (In the past, you had to
5398 try twice in order to list an include file that you hadn't looked at before.)
5400 * Interesting infernals change
5402 GDB now deals with arbitrary numbers of sections, where the symbols for each
5403 section must be relocated relative to that section's landing place in the
5404 target's address space. This work was needed to support ELF with embedded
5405 stabs used by Solaris-2.0.
5407 * Bug fixes (of course!)
5409 There have been loads of fixes for the following things:
5410 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5411 i960, stabs, DOS(GO32), procfs, etc...
5413 See the ChangeLog for details.
5415 *** Changes in GDB-4.5:
5417 * New machines supported (host and target)
5419 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5421 SGI Irix-4.x mips-sgi-irix4 or iris4
5423 * New malloc package
5425 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5426 Mmalloc is capable of handling mutiple heaps of memory. It is also
5427 capable of saving a heap to a file, and then mapping it back in later.
5428 This can be used to greatly speedup the startup of GDB by using a
5429 pre-parsed symbol table which lives in a mmalloc managed heap. For
5430 more details, please read mmalloc/mmalloc.texi.
5434 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5435 'help info proc' for details.
5437 * MIPS ecoff symbol table format
5439 The code that reads MIPS symbol table format is now supported on all hosts.
5440 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5443 * File name changes for MS-DOS
5445 Many files in the config directories have been renamed to make it easier to
5446 support GDB on MS-DOSe systems (which have very restrictive file name
5447 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5448 environment) is close to working but has some remaining problems. Note
5449 that debugging of DOS programs is not supported, due to limitations
5450 in the ``operating system'', but it can be used to host cross-debugging.
5452 * Cross byte order fixes
5454 Many fixes have been made to support cross debugging of Sparc and MIPS
5455 targets from hosts whose byte order differs.
5457 * New -mapped and -readnow options
5459 If memory-mapped files are available on your system through the 'mmap'
5460 system call, you can use the -mapped option on the `file' or
5461 `symbol-file' commands to cause GDB to write the symbols from your
5462 program into a reusable file. If the program you are debugging is
5463 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5464 Future GDB debugging sessions will notice the presence of this file,
5465 and will quickly map in symbol information from it, rather than reading
5466 the symbol table from the executable program. Using the '-mapped'
5467 option in a GDB `file' or `symbol-file' command has the same effect as
5468 starting GDB with the '-mapped' command-line option.
5470 You can cause GDB to read the entire symbol table immediately by using
5471 the '-readnow' option with any of the commands that load symbol table
5472 information (or on the GDB command line). This makes the command
5473 slower, but makes future operations faster.
5475 The -mapped and -readnow options are typically combined in order to
5476 build a `fred.syms' file that contains complete symbol information.
5477 A simple GDB invocation to do nothing but build a `.syms' file for future
5480 gdb -batch -nx -mapped -readnow programname
5482 The `.syms' file is specific to the host machine on which GDB is run.
5483 It holds an exact image of GDB's internal symbol table. It cannot be
5484 shared across multiple host platforms.
5486 * longjmp() handling
5488 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5489 siglongjmp() without losing control. This feature has not yet been ported to
5490 all systems. It currently works on many 386 platforms, all MIPS-based
5491 platforms (SGI, DECstation, etc), and Sun3/4.
5495 Preliminary work has been put in to support the new Solaris OS from Sun. At
5496 this time, it can control and debug processes, but it is not capable of
5501 As always, many many bug fixes. The major areas were with g++, and mipsread.
5502 People using the MIPS-based platforms should experience fewer mysterious
5503 crashes and trashed symbol tables.
5505 *** Changes in GDB-4.4:
5507 * New machines supported (host and target)
5509 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5511 BSD Reno on Vax vax-dec-bsd
5512 Ultrix on Vax vax-dec-ultrix
5514 * New machines supported (target)
5516 AMD 29000 embedded, using EBMON a29k-none-none
5520 GDB continues to improve its handling of C++. `References' work better.
5521 The demangler has also been improved, and now deals with symbols mangled as
5522 per the Annotated C++ Reference Guide.
5524 GDB also now handles `stabs' symbol information embedded in MIPS
5525 `ecoff' symbol tables. Since the ecoff format was not easily
5526 extensible to handle new languages such as C++, this appeared to be a
5527 good way to put C++ debugging info into MIPS binaries. This option
5528 will be supported in the GNU C compiler, version 2, when it is
5531 * New features for SVR4
5533 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5534 shared libraries. Debugging dynamically linked programs should present
5535 only minor differences from debugging statically linked programs.
5537 The `info proc' command will print out information about any process
5538 on an SVR4 system (including the one you are debugging). At the moment,
5539 it prints the address mappings of the process.
5541 If you bring up GDB on another SVR4 system, please send mail to
5542 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5544 * Better dynamic linking support in SunOS
5546 Reading symbols from shared libraries which contain debugging symbols
5547 now works properly. However, there remain issues such as automatic
5548 skipping of `transfer vector' code during function calls, which
5549 make it harder to debug code in a shared library, than to debug the
5550 same code linked statically.
5554 GDB is now using the latest `getopt' routines from the FSF. This
5555 version accepts the -- prefix for options with long names. GDB will
5556 continue to accept the old forms (-option and +option) as well.
5557 Various single letter abbreviations for options have been explicity
5558 added to the option table so that they won't get overshadowed in the
5559 future by other options that begin with the same letter.
5563 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5564 Many assorted bugs have been handled. Many more remain to be handled.
5565 See the various ChangeLog files (primarily in gdb and bfd) for details.
5568 *** Changes in GDB-4.3:
5570 * New machines supported (host and target)
5572 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5573 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5574 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5576 * Almost SCO Unix support
5578 We had hoped to support:
5579 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5580 (except for core file support), but we discovered very late in the release
5581 that it has problems with process groups that render gdb unusable. Sorry
5582 about that. I encourage people to fix it and post the fixes.
5584 * Preliminary ELF and DWARF support
5586 GDB can read ELF object files on System V Release 4, and can handle
5587 debugging records for C, in DWARF format, in ELF files. This support
5588 is preliminary. If you bring up GDB on another SVR4 system, please
5589 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5594 GDB now uses the latest `readline' library. One user-visible change
5595 is that two tabs will list possible command completions, which previously
5596 required typing M-? (meta-question mark, or ESC ?).
5600 The `stepi' bug that many of you noticed has been squashed.
5601 Many bugs in C++ have been handled. Many more remain to be handled.
5602 See the various ChangeLog files (primarily in gdb and bfd) for details.
5604 * State of the MIPS world (in case you wondered):
5606 GDB can understand the symbol tables emitted by the compilers
5607 supplied by most vendors of MIPS-based machines, including DEC. These
5608 symbol tables are in a format that essentially nobody else uses.
5610 Some versions of gcc come with an assembler post-processor called
5611 mips-tfile. This program is required if you want to do source-level
5612 debugging of gcc-compiled programs. I believe FSF does not ship
5613 mips-tfile with gcc version 1, but it will eventually come with gcc
5616 Debugging of g++ output remains a problem. g++ version 1.xx does not
5617 really support it at all. (If you're lucky, you should be able to get
5618 line numbers and stack traces to work, but no parameters or local
5619 variables.) With some work it should be possible to improve the
5622 When gcc version 2 is released, you will have somewhat better luck.
5623 However, even then you will get confusing results for inheritance and
5626 We will eventually provide full debugging of g++ output on
5627 DECstations. This will probably involve some kind of stabs-in-ecoff
5628 encapulation, but the details have not been worked out yet.
5631 *** Changes in GDB-4.2:
5633 * Improved configuration
5635 Only one copy of `configure' exists now, and it is not self-modifying.
5636 Porting BFD is simpler.
5640 The `step' and `next' commands now only stop at the first instruction
5641 of a source line. This prevents the multiple stops that used to occur
5642 in switch statements, for-loops, etc. `Step' continues to stop if a
5643 function that has debugging information is called within the line.
5647 Lots of small bugs fixed. More remain.
5649 * New host supported (not target)
5651 Intel 386 PC clone running Mach i386-none-mach
5654 *** Changes in GDB-4.1:
5656 * Multiple source language support
5658 GDB now has internal scaffolding to handle several source languages.
5659 It determines the type of each source file from its filename extension,
5660 and will switch expression parsing and number formatting to match the
5661 language of the function in the currently selected stack frame.
5662 You can also specifically set the language to be used, with
5663 `set language c' or `set language modula-2'.
5667 GDB now has preliminary support for the GNU Modula-2 compiler,
5668 currently under development at the State University of New York at
5669 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5670 continue through the fall of 1991 and into 1992.
5672 Other Modula-2 compilers are currently not supported, and attempting to
5673 debug programs compiled with them will likely result in an error as the
5674 symbol table is read. Feel free to work on it, though!
5676 There are hooks in GDB for strict type checking and range checking,
5677 in the `Modula-2 philosophy', but they do not currently work.
5681 GDB can now write to executable and core files (e.g. patch
5682 a variable's value). You must turn this switch on, specify
5683 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5684 by assigning a new value to a variable. Modifications take
5687 * Automatic SunOS shared library reading
5689 When you run your program, GDB automatically determines where its
5690 shared libraries (if any) have been loaded, and reads their symbols.
5691 The `share' command is no longer needed. This also works when
5692 examining core files.
5696 You can specify the number of lines that the `list' command shows.
5699 * New machines supported (host and target)
5701 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5702 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5703 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5705 * New hosts supported (not targets)
5707 IBM RT/PC: romp-ibm-aix or rtpc
5709 * New targets supported (not hosts)
5711 AMD 29000 embedded with COFF a29k-none-coff
5712 AMD 29000 embedded with a.out a29k-none-aout
5713 Ultracomputer remote kernel debug a29k-nyu-kern
5715 * New remote interfaces
5721 *** Changes in GDB-4.0:
5725 Wide output is wrapped at good places to make the output more readable.
5727 Gdb now supports cross-debugging from a host machine of one type to a
5728 target machine of another type. Communication with the target system
5729 is over serial lines. The ``target'' command handles connecting to the
5730 remote system; the ``load'' command will download a program into the
5731 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5732 also supports debugging of realtime processes running under VxWorks,
5733 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5734 stub on the target system.
5736 New CPUs supported include the AMD 29000 and Intel 960.
5738 GDB now reads object files and symbol tables via a ``binary file''
5739 library, which allows a single copy of GDB to debug programs of multiple
5740 object file types such as a.out and coff.
5742 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5743 refcard.dvi and refcard.ps are available to format it).
5746 * Control-Variable user interface simplified
5748 All variables that control the operation of the debugger can be set
5749 by the ``set'' command, and displayed by the ``show'' command.
5751 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5752 ``Show prompt'' produces the response:
5753 Gdb's prompt is new-gdb=>.
5755 What follows are the NEW set commands. The command ``help set'' will
5756 print a complete list of old and new set commands. ``help set FOO''
5757 will give a longer description of the variable FOO. ``show'' will show
5758 all of the variable descriptions and their current settings.
5760 confirm on/off: Enables warning questions for operations that are
5761 hard to recover from, e.g. rerunning the program while
5762 it is already running. Default is ON.
5764 editing on/off: Enables EMACS style command line editing
5765 of input. Previous lines can be recalled with
5766 control-P, the current line can be edited with control-B,
5767 you can search for commands with control-R, etc.
5770 history filename NAME: NAME is where the gdb command history
5771 will be stored. The default is .gdb_history,
5772 or the value of the environment variable
5775 history size N: The size, in commands, of the command history. The
5776 default is 256, or the value of the environment variable
5779 history save on/off: If this value is set to ON, the history file will
5780 be saved after exiting gdb. If set to OFF, the
5781 file will not be saved. The default is OFF.
5783 history expansion on/off: If this value is set to ON, then csh-like
5784 history expansion will be performed on
5785 command line input. The default is OFF.
5787 radix N: Sets the default radix for input and output. It can be set
5788 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5789 in the current radix, so "set radix 10" is always a no-op.
5791 height N: This integer value is the number of lines on a page. Default
5792 is 24, the current `stty rows'' setting, or the ``li#''
5793 setting from the termcap entry matching the environment
5796 width N: This integer value is the number of characters on a line.
5797 Default is 80, the current `stty cols'' setting, or the ``co#''
5798 setting from the termcap entry matching the environment
5801 Note: ``set screensize'' is obsolete. Use ``set height'' and
5802 ``set width'' instead.
5804 print address on/off: Print memory addresses in various command displays,
5805 such as stack traces and structure values. Gdb looks
5806 more ``symbolic'' if you turn this off; it looks more
5807 ``machine level'' with it on. Default is ON.
5809 print array on/off: Prettyprint arrays. New convenient format! Default
5812 print demangle on/off: Print C++ symbols in "source" form if on,
5815 print asm-demangle on/off: Same, for assembler level printouts
5818 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5821 * Support for Epoch Environment.
5823 The epoch environment is a version of Emacs v18 with windowing. One
5824 new command, ``inspect'', is identical to ``print'', except that if you
5825 are running in the epoch environment, the value is printed in its own
5829 * Support for Shared Libraries
5831 GDB can now debug programs and core files that use SunOS shared libraries.
5832 Symbols from a shared library cannot be referenced
5833 before the shared library has been linked with the program (this
5834 happens after you type ``run'' and before the function main() is entered).
5835 At any time after this linking (including when examining core files
5836 from dynamically linked programs), gdb reads the symbols from each
5837 shared library when you type the ``sharedlibrary'' command.
5838 It can be abbreviated ``share''.
5840 sharedlibrary REGEXP: Load shared object library symbols for files
5841 matching a unix regular expression. No argument
5842 indicates to load symbols for all shared libraries.
5844 info sharedlibrary: Status of loaded shared libraries.
5849 A watchpoint stops execution of a program whenever the value of an
5850 expression changes. Checking for this slows down execution
5851 tremendously whenever you are in the scope of the expression, but is
5852 quite useful for catching tough ``bit-spreader'' or pointer misuse
5853 problems. Some machines such as the 386 have hardware for doing this
5854 more quickly, and future versions of gdb will use this hardware.
5856 watch EXP: Set a watchpoint (breakpoint) for an expression.
5858 info watchpoints: Information about your watchpoints.
5860 delete N: Deletes watchpoint number N (same as breakpoints).
5861 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5862 enable N: Re-enables watchpoint number N (same as breakpoints).
5865 * C++ multiple inheritance
5867 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5870 * C++ exception handling
5872 Gdb now supports limited C++ exception handling. Besides the existing
5873 ability to breakpoint on an exception handler, gdb can breakpoint on
5874 the raising of an exception (before the stack is peeled back to the
5877 catch FOO: If there is a FOO exception handler in the dynamic scope,
5878 set a breakpoint to catch exceptions which may be raised there.
5879 Multiple exceptions (``catch foo bar baz'') may be caught.
5881 info catch: Lists all exceptions which may be caught in the
5882 current stack frame.
5885 * Minor command changes
5887 The command ``call func (arg, arg, ...)'' now acts like the print
5888 command, except it does not print or save a value if the function's result
5889 is void. This is similar to dbx usage.
5891 The ``up'' and ``down'' commands now always print the frame they end up
5892 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5893 frames without printing.
5895 * New directory command
5897 'dir' now adds directories to the FRONT of the source search path.
5898 The path starts off empty. Source files that contain debug information
5899 about the directory in which they were compiled can be found even
5900 with an empty path; Sun CC and GCC include this information. If GDB can't
5901 find your source file in the current directory, type "dir .".
5903 * Configuring GDB for compilation
5905 For normal use, type ``./configure host''. See README or gdb.texinfo
5908 GDB now handles cross debugging. If you are remotely debugging between
5909 two different machines, type ``./configure host -target=targ''.
5910 Host is the machine where GDB will run; targ is the machine
5911 where the program that you are debugging will run.