1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
7 * GDB now honors the content of the file /proc/PID/coredump_filter
8 (PID is the process ID) on GNU/Linux systems. This file can be used
9 to specify the types of memory mappings that will be included in a
10 corefile. For more information, please refer to the manual page of
11 "core(5)". GDB also has a new command: "set use-coredump-filter
12 on|off". It allows to set whether GDB will read the content of the
13 /proc/PID/coredump_filter file when generating a corefile.
15 * The "info os" command on GNU/Linux can now display information on
17 "info os cpus" Listing of all cpus/cores on the system
19 * GDB has two new commands: "set serial parity odd|even|none" and
20 "show serial parity". These allows to set or show parity for the
23 * The "info source" command now displays the producer string if it was
24 present in the debug info. This typically includes the compiler version
25 and may include things like its command line arguments.
29 ** gdb.Objfile objects have a new attribute "username",
30 which is the name of the objfile as specified by the user,
31 without, for example, resolving symlinks.
32 ** You can now write frame unwinders in Python.
36 maint print symbol-cache
37 Print the contents of the symbol cache.
39 maint print symbol-cache-statistics
40 Print statistics of symbol cache usage.
42 maint flush-symbol-cache
43 Flush the contents of the symbol cache.
47 Start branch trace recording using Branch Trace Store (BTS) format.
53 Set the maximum number of candidates to be considered during
54 completion. The default value is 200. This limit allows GDB
55 to avoid generating large completion lists, the computation of
56 which can cause the debugger to become temporarily unresponsive.
58 maint set symbol-cache-size
59 maint show symbol-cache-size
60 Control the size of the symbol cache.
62 set|show record btrace bts buffer-size
63 Set and show the size of the ring buffer used for branch tracing in
65 The obtained size may differ from the requested size. Use "info
66 record" to see the obtained buffer size.
68 * The command 'thread apply all' can now support new option '-ascending'
69 to call its specified command for all threads in ascending order.
71 * Python/Guile scripting
73 ** GDB now supports auto-loading of Python/Guile scripts contained in the
74 special section named `.debug_gdb_scripts'.
78 qXfer:btrace-conf:read
79 Return the branch trace configuration for the current thread.
82 Set the requested ring buffer size for branch tracing in BTS format.
85 Indicates a memory breakpoint instruction was executed, irrespective
86 of whether it was GDB that planted the breakpoint or the breakpoint
87 is hardcoded in the program. This is required for correct non-stop
91 Indicates the target stopped for a hardware breakpoint. This is
92 required for correct non-stop mode operation.
95 Return information about files on the remote system.
97 * The info record command now shows the recording format and the
98 branch tracing configuration for the current thread when using
99 the btrace record target.
100 For the BTS format, it shows the ring buffer size.
102 * GDB now has support for DTrace USDT (Userland Static Defined
103 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
105 * GDB now supports access to vector registers on S/390 GNU/Linux
108 * Removed targets and native configurations
110 HP/PA running HP-UX hppa*-*-hpux*
111 Itanium running HP-UX ia64-*-hpux*
113 *** Changes in GDB 7.9
115 * GDB now supports hardware watchpoints on x86 GNU Hurd.
119 ** You can now access frame registers from Python scripts.
120 ** New attribute 'producer' for gdb.Symtab objects.
121 ** gdb.Objfile objects have a new attribute "progspace",
122 which is the gdb.Progspace object of the containing program space.
123 ** gdb.Objfile objects have a new attribute "owner".
124 ** gdb.Objfile objects have a new attribute "build_id",
125 which is the build ID generated when the file was built.
126 ** gdb.Objfile objects have a new method "add_separate_debug_file".
127 ** A new event "gdb.clear_objfiles" has been added, triggered when
128 selecting a new file to debug.
129 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
130 ** New function gdb.lookup_objfile.
132 New events which are triggered when GDB modifies the state of the
135 ** gdb.events.inferior_call_pre: Function call is about to be made.
136 ** gdb.events.inferior_call_post: Function call has just been made.
137 ** gdb.events.memory_changed: A memory location has been altered.
138 ** gdb.events.register_changed: A register has been altered.
140 * New Python-based convenience functions:
142 ** $_caller_is(name [, number_of_frames])
143 ** $_caller_matches(regexp [, number_of_frames])
144 ** $_any_caller_is(name [, number_of_frames])
145 ** $_any_caller_matches(regexp [, number_of_frames])
147 * GDB now supports the compilation and injection of source code into
148 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
149 to compile the source code to object code, and if successful, inject
150 and execute that code within the current context of the inferior.
151 Currently the C language is supported. The commands used to
152 interface with this new feature are:
154 compile code [-raw|-r] [--] [source code]
155 compile file [-raw|-r] filename
159 demangle [-l language] [--] name
160 Demangle "name" in the specified language, or the current language
161 if elided. This command is renamed from the "maint demangle" command.
162 The latter is kept as a no-op to avoid "maint demangle" being interpreted
163 as "maint demangler-warning".
165 queue-signal signal-name-or-number
166 Queue a signal to be delivered to the thread when it is resumed.
168 add-auto-load-scripts-directory directory
169 Add entries to the list of directories from which to load auto-loaded
172 maint print user-registers
173 List all currently available "user" registers.
175 compile code [-r|-raw] [--] [source code]
176 Compile, inject, and execute in the inferior the executable object
177 code produced by compiling the provided source code.
179 compile file [-r|-raw] filename
180 Compile and inject into the inferior the executable object code
181 produced by compiling the source code stored in the filename
184 * On resume, GDB now always passes the signal the program had stopped
185 for to the thread the signal was sent to, even if the user changed
186 threads before resuming. Previously GDB would often (but not
187 always) deliver the signal to the thread that happens to be current
190 * Conversely, the "signal" command now consistently delivers the
191 requested signal to the current thread. GDB now asks for
192 confirmation if the program had stopped for a signal and the user
193 switched threads meanwhile.
195 * "breakpoint always-inserted" modes "off" and "auto" merged.
197 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
198 won't remove breakpoints from the target until all threads stop,
199 even in non-stop mode. The "auto" mode has been removed, and "off"
200 is now the default mode.
204 set debug symbol-lookup
205 show debug symbol-lookup
206 Control display of debugging info regarding symbol lookup.
210 ** The -list-thread-groups command outputs an exit-code field for
211 inferiors that have exited.
215 MIPS SDE mips*-sde*-elf*
219 Support for these obsolete configurations has been removed.
221 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
222 SGI Irix-5.x mips-*-irix5*
223 SGI Irix-6.x mips-*-irix6*
224 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
225 VAX running Ultrix vax-*-ultrix*
227 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
228 and "assf"), have been removed. Use the "sharedlibrary" command, or
229 its alias "share", instead.
231 *** Changes in GDB 7.8
233 * New command line options
236 This is an alias for the --data-directory option.
238 * GDB supports printing and modifying of variable length automatic arrays
239 as specified in ISO C99.
241 * The ARM simulator now supports instruction level tracing
242 with or without disassembly.
246 GDB now has support for scripting using Guile. Whether this is
247 available is determined at configure time.
248 Guile version 2.0 or greater is required.
249 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
251 * New commands (for set/show, see "New options" below)
255 Invoke CODE by passing it to the Guile interpreter.
259 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
261 info auto-load guile-scripts [regexp]
262 Print the list of automatically loaded Guile scripts.
264 * The source command is now capable of sourcing Guile scripts.
265 This feature is dependent on the debugger being built with Guile support.
269 set print symbol-loading (off|brief|full)
270 show print symbol-loading
271 Control whether to print informational messages when loading symbol
272 information for a file. The default is "full", but when debugging
273 programs with large numbers of shared libraries the amount of output
276 set guile print-stack (none|message|full)
277 show guile print-stack
278 Show a stack trace when an error is encountered in a Guile script.
280 set auto-load guile-scripts (on|off)
281 show auto-load guile-scripts
282 Control auto-loading of Guile script files.
284 maint ada set ignore-descriptive-types (on|off)
285 maint ada show ignore-descriptive-types
286 Control whether the debugger should ignore descriptive types in Ada
287 programs. The default is not to ignore the descriptive types. See
288 the user manual for more details on descriptive types and the intended
289 usage of this option.
291 set auto-connect-native-target
293 Control whether GDB is allowed to automatically connect to the
294 native target for the run, attach, etc. commands when not connected
295 to any target yet. See also "target native" below.
297 set record btrace replay-memory-access (read-only|read-write)
298 show record btrace replay-memory-access
299 Control what memory accesses are allowed during replay.
301 maint set target-async (on|off)
302 maint show target-async
303 This controls whether GDB targets operate in synchronous or
304 asynchronous mode. Normally the default is asynchronous, if it is
305 available; but this can be changed to more easily debug problems
306 occurring only in synchronous mode.
308 set mi-async (on|off)
310 Control whether MI asynchronous mode is preferred. This supersedes
311 "set target-async" of previous GDB versions.
313 * "set target-async" is deprecated as a CLI option and is now an alias
314 for "set mi-async" (only puts MI into async mode).
316 * Background execution commands (e.g., "c&", "s&", etc.) are now
317 possible ``out of the box'' if the target supports them. Previously
318 the user would need to explicitly enable the possibility with the
319 "set target-async on" command.
321 * New features in the GDB remote stub, GDBserver
323 ** New option --debug-format=option1[,option2,...] allows one to add
324 additional text to each output. At present only timestamps
325 are supported: --debug-format=timestamps.
326 Timestamps can also be turned on with the
327 "monitor set debug-format timestamps" command from GDB.
329 * The 'record instruction-history' command now starts counting instructions
330 at one. This also affects the instruction ranges reported by the
331 'record function-call-history' command when given the /i modifier.
333 * The command 'record function-call-history' supports a new modifier '/c' to
334 indent the function names based on their call stack depth.
335 The fields for the '/i' and '/l' modifier have been reordered.
336 The source line range is now prefixed with 'at'.
337 The instruction range is now prefixed with 'inst'.
338 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
339 "record instruction-history" and "list" commands.
341 * The ranges given as arguments to the 'record function-call-history' and
342 'record instruction-history' commands are now inclusive.
344 * The btrace record target now supports the 'record goto' command.
345 For locations inside the execution trace, the back trace is computed
346 based on the information stored in the execution trace.
348 * The btrace record target supports limited reverse execution and replay.
349 The target does not record data and therefore does not allow reading
352 * The "catch syscall" command now works on s390*-linux* targets.
354 * The "compare-sections" command is no longer specific to target
355 remote. It now works with all targets.
357 * All native targets are now consistently called "native".
358 Consequently, the "target child", "target GNU", "target djgpp",
359 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
360 commands have been replaced with "target native". The QNX/NTO port
361 leaves the "procfs" target in place and adds a "native" target for
362 consistency with other ports. The impact on users should be minimal
363 as these commands previously either throwed an error, or were
364 no-ops. The target's name is visible in the output of the following
365 commands: "help target", "info target", "info files", "maint print
368 * The "target native" command now connects to the native target. This
369 can be used to launch native programs even when "set
370 auto-connect-native-target" is set to off.
372 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
374 * Support for Intel(R) AVX-512 registers on GNU/Linux.
375 Support displaying and modifying Intel(R) AVX-512 registers
376 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
380 qXfer:btrace:read's annex
381 The qXfer:btrace:read packet supports a new annex 'delta' to read
382 branch trace incrementally.
386 ** Valid Python operations on gdb.Value objects representing
387 structs/classes invoke the corresponding overloaded operators if
389 ** New `Xmethods' feature in the Python API. Xmethods are
390 additional methods or replacements for existing methods of a C++
391 class. This feature is useful for those cases where a method
392 defined in C++ source code could be inlined or optimized out by
393 the compiler, making it unavailable to GDB.
396 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
398 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
399 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
400 its alias "share", instead.
402 * The commands "set remotebaud" and "show remotebaud" are no longer
403 supported. Use "set serial baud" and "show serial baud" (respectively)
408 ** A new option "-gdb-set mi-async" replaces "-gdb-set
409 target-async". The latter is left as a deprecated alias of the
410 former for backward compatibility. If the target supports it,
411 CLI background execution commands are now always possible by
412 default, independently of whether the frontend stated a
413 preference for asynchronous execution with "-gdb-set mi-async".
414 Previously "-gdb-set target-async off" affected both MI execution
415 commands and CLI execution commands.
417 *** Changes in GDB 7.7
419 * Improved support for process record-replay and reverse debugging on
420 arm*-linux* targets. Support for thumb32 and syscall instruction
421 recording has been added.
423 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
425 * GDB now supports Fission DWP file format version 2.
426 http://gcc.gnu.org/wiki/DebugFission
428 * New convenience function "$_isvoid", to check whether an expression
429 is void. A void expression is an expression where the type of the
430 result is "void". For example, some convenience variables may be
431 "void" when evaluated (e.g., "$_exitcode" before the execution of
432 the program being debugged; or an undefined convenience variable).
433 Another example, when calling a function whose return type is
436 * The "maintenance print objfiles" command now takes an optional regexp.
438 * The "catch syscall" command now works on arm*-linux* targets.
440 * GDB now consistently shows "<not saved>" when printing values of
441 registers the debug info indicates have not been saved in the frame
442 and there's nowhere to retrieve them from
443 (callee-saved/call-clobbered registers):
448 (gdb) info registers rax
451 Before, the former would print "<optimized out>", and the latter
452 "*value not available*".
454 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
459 ** Frame filters and frame decorators have been added.
460 ** Temporary breakpoints are now supported.
461 ** Line tables representation has been added.
462 ** New attribute 'parent_type' for gdb.Field objects.
463 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
464 ** New attribute 'name' for gdb.Type objects.
468 Nios II ELF nios2*-*-elf
469 Nios II GNU/Linux nios2*-*-linux
470 Texas Instruments MSP430 msp430*-*-elf
472 * Removed native configurations
474 Support for these a.out NetBSD and OpenBSD obsolete configurations has
475 been removed. ELF variants of these configurations are kept supported.
477 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
478 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
479 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
480 i[34567]86-*-openbsd3.[0-3]
481 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
482 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
483 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
487 Like "catch throw", but catches a re-thrown exception.
489 Renamed from old "maint check-symtabs".
491 Perform consistency checks on symtabs.
493 Expand symtabs matching an optional regexp.
496 Display the details of GDB configure-time options.
498 maint set|show per-command
499 maint set|show per-command space
500 maint set|show per-command time
501 maint set|show per-command symtab
502 Enable display of per-command gdb resource usage.
504 remove-symbol-file FILENAME
505 remove-symbol-file -a ADDRESS
506 Remove a symbol file added via add-symbol-file. The file to remove
507 can be identified by its filename or by an address that lies within
508 the boundaries of this symbol file in memory.
511 info exceptions REGEXP
512 Display the list of Ada exceptions defined in the program being
513 debugged. If provided, only the exceptions whose names match REGEXP
518 set debug symfile off|on
520 Control display of debugging info regarding reading symbol files and
521 symbol tables within those files
523 set print raw frame-arguments
524 show print raw frame-arguments
525 Set/show whether to print frame arguments in raw mode,
526 disregarding any defined pretty-printers.
528 set remote trace-status-packet
529 show remote trace-status-packet
530 Set/show the use of remote protocol qTStatus packet.
534 Control display of debugging messages related to Nios II targets.
538 Control whether target-assisted range stepping is enabled.
540 set startup-with-shell
541 show startup-with-shell
542 Specifies whether Unix child processes are started via a shell or
547 Use the target memory cache for accesses to the code segment. This
548 improves performance of remote debugging (particularly disassembly).
550 * You can now use a literal value 'unlimited' for options that
551 interpret 0 or -1 as meaning "unlimited". E.g., "set
552 trace-buffer-size unlimited" is now an alias for "set
553 trace-buffer-size -1" and "set height unlimited" is now an alias for
556 * The "set debug symtab-create" debugging option of GDB has been changed to
557 accept a verbosity level. 0 means "off", 1 provides basic debugging
558 output, and values of 2 or greater provides more verbose output.
560 * New command-line options
562 Display the details of GDB configure-time options.
564 * The command 'tsave' can now support new option '-ctf' to save trace
565 buffer in Common Trace Format.
567 * Newly installed $prefix/bin/gcore acts as a shell interface for the
570 * GDB now implements the the C++ 'typeid' operator.
572 * The new convenience variable $_exception holds the exception being
573 thrown or caught at an exception-related catchpoint.
575 * The exception-related catchpoints, like "catch throw", now accept a
576 regular expression which can be used to filter exceptions by type.
578 * The new convenience variable $_exitsignal is automatically set to
579 the terminating signal number when the program being debugged dies
580 due to an uncaught signal.
584 ** All MI commands now accept an optional "--language" option.
585 Support for this feature can be verified by using the "-list-features"
586 command, which should contain "language-option".
588 ** The new command -info-gdb-mi-command allows the user to determine
589 whether a GDB/MI command is supported or not.
591 ** The "^error" result record returned when trying to execute an undefined
592 GDB/MI command now provides a variable named "code" whose content is the
593 "undefined-command" error code. Support for this feature can be verified
594 by using the "-list-features" command, which should contain
595 "undefined-command-error-code".
597 ** The -trace-save MI command can optionally save trace buffer in Common
600 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
602 ** The command -data-list-register-values now accepts an optional
603 "--skip-unavailable" option. When used, only the available registers
606 ** The new command -trace-frame-collected dumps collected variables,
607 computed expressions, tvars, memory and registers in a traceframe.
609 ** The commands -stack-list-locals, -stack-list-arguments and
610 -stack-list-variables now accept an option "--skip-unavailable".
611 When used, only the available locals or arguments are displayed.
613 ** The -exec-run command now accepts an optional "--start" option.
614 When used, the command follows the same semantics as the "start"
615 command, stopping the program's execution at the start of its
616 main subprogram. Support for this feature can be verified using
617 the "-list-features" command, which should contain
618 "exec-run-start-option".
620 ** The new commands -catch-assert and -catch-exceptions insert
621 catchpoints stopping the program when Ada exceptions are raised.
623 ** The new command -info-ada-exceptions provides the equivalent of
624 the new "info exceptions" command.
626 * New system-wide configuration scripts
627 A GDB installation now provides scripts suitable for use as system-wide
628 configuration scripts for the following systems:
632 * GDB now supports target-assigned range stepping with remote targets.
633 This improves the performance of stepping source lines by reducing
634 the number of control packets from/to GDB. See "New remote packets"
637 * GDB now understands the element 'tvar' in the XML traceframe info.
638 It has the id of the collected trace state variables.
640 * On S/390 targets that provide the transactional-execution feature,
641 the program interruption transaction diagnostic block (TDB) is now
642 represented as a number of additional "registers" in GDB.
648 The vCont packet supports a new 'r' action, that tells the remote
649 stub to step through an address range itself, without GDB
650 involvemement at each single-step.
652 qXfer:libraries-svr4:read's annex
653 The previously unused annex of the qXfer:libraries-svr4:read packet
654 is now used to support passing an argument list. The remote stub
655 reports support for this argument list to GDB's qSupported query.
656 The defined arguments are "start" and "prev", used to reduce work
657 necessary for library list updating, resulting in significant
660 * New features in the GDB remote stub, GDBserver
662 ** GDBserver now supports target-assisted range stepping. Currently
663 enabled on x86/x86_64 GNU/Linux targets.
665 ** GDBserver now adds element 'tvar' in the XML in the reply to
666 'qXfer:traceframe-info:read'. It has the id of the collected
667 trace state variables.
669 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
672 * New 'z' formatter for printing and examining memory, this displays the
673 value as hexadecimal zero padded on the left to the size of the type.
675 * GDB can now use Windows x64 unwinding data.
677 * The "set remotebaud" command has been replaced by "set serial baud".
678 Similarly, "show remotebaud" has been replaced by "show serial baud".
679 The "set remotebaud" and "show remotebaud" commands are still available
680 to provide backward compatibility with older versions of GDB.
682 *** Changes in GDB 7.6
684 * Target record has been renamed to record-full.
685 Record/replay is now enabled with the "record full" command.
686 This also affects settings that are associated with full record/replay
687 that have been moved from "set/show record" to "set/show record full":
689 set|show record full insn-number-max
690 set|show record full stop-at-limit
691 set|show record full memory-query
693 * A new record target "record-btrace" has been added. The new target
694 uses hardware support to record the control-flow of a process. It
695 does not support replaying the execution, but it implements the
696 below new commands for investigating the recorded execution log.
697 This new recording method can be enabled using:
701 The "record-btrace" target is only available on Intel Atom processors
702 and requires a Linux kernel 2.6.32 or later.
704 * Two new commands have been added for record/replay to give information
705 about the recorded execution without having to replay the execution.
706 The commands are only supported by "record btrace".
708 record instruction-history prints the execution history at
709 instruction granularity
711 record function-call-history prints the execution history at
714 * New native configurations
716 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
717 FreeBSD/powerpc powerpc*-*-freebsd
718 x86_64/Cygwin x86_64-*-cygwin*
719 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
723 ARM AArch64 aarch64*-*-elf
724 ARM AArch64 GNU/Linux aarch64*-*-linux
725 Lynx 178 PowerPC powerpc-*-lynx*178
726 x86_64/Cygwin x86_64-*-cygwin*
727 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
729 * If the configured location of system.gdbinit file (as given by the
730 --with-system-gdbinit option at configure time) is in the
731 data-directory (as specified by --with-gdb-datadir at configure
732 time) or in one of its subdirectories, then GDB will look for the
733 system-wide init file in the directory specified by the
734 --data-directory command-line option.
736 * New command line options:
738 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
739 other initialization files, unlike -nx which disables all of them.
741 * Removed command line options
743 -epoch This was used by the gdb mode in Epoch, an ancient fork of
746 * The 'ptype' and 'whatis' commands now accept an argument to control
749 * 'info proc' now works on some core files.
753 ** Vectors can be created with gdb.Type.vector.
755 ** Python's atexit.register now works in GDB.
757 ** Types can be pretty-printed via a Python API.
759 ** Python 3 is now supported (in addition to Python 2.4 or later)
761 ** New class gdb.Architecture exposes GDB's internal representation
762 of architecture in the Python API.
764 ** New method Frame.architecture returns the gdb.Architecture object
765 corresponding to the frame's architecture.
767 * New Python-based convenience functions:
769 ** $_memeq(buf1, buf2, length)
770 ** $_streq(str1, str2)
772 ** $_regex(str, regex)
774 * The 'cd' command now defaults to using '~' (the home directory) if not
777 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
778 default for GCC since November 2000.
780 * The command 'forward-search' can now be abbreviated as 'fo'.
782 * The command 'info tracepoints' can now display 'installed on target'
783 or 'not installed on target' for each non-pending location of tracepoint.
785 * New configure options
787 --enable-libmcheck/--disable-libmcheck
788 By default, development versions are built with -lmcheck on hosts
789 that support it, in order to help track memory corruption issues.
790 Release versions, on the other hand, are built without -lmcheck
791 by default. The --enable-libmcheck/--disable-libmcheck configure
792 options allow the user to override that default.
793 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
794 This configure option allows the user to build GDB with
795 libbabeltrace using which GDB can read Common Trace Format data.
797 * New commands (for set/show, see "New options" below)
800 Catch signals. This is similar to "handle", but allows commands and
801 conditions to be attached.
804 List the BFDs known to GDB.
806 python-interactive [command]
808 Start a Python interactive prompt, or evaluate the optional command
809 and print the result of expressions.
812 "py" is a new alias for "python".
814 enable type-printer [name]...
815 disable type-printer [name]...
816 Enable or disable type printers.
820 ** For the Renesas Super-H architecture, the "regs" command has been removed
821 (has been deprecated in GDB 7.5), and "info all-registers" should be used
826 set print type methods (on|off)
827 show print type methods
828 Control whether method declarations are displayed by "ptype".
829 The default is to show them.
831 set print type typedefs (on|off)
832 show print type typedefs
833 Control whether typedef definitions are displayed by "ptype".
834 The default is to show them.
836 set filename-display basename|relative|absolute
837 show filename-display
838 Control the way in which filenames is displayed.
839 The default is "relative", which preserves previous behavior.
841 set trace-buffer-size
842 show trace-buffer-size
843 Request target to change the size of trace buffer.
845 set remote trace-buffer-size-packet auto|on|off
846 show remote trace-buffer-size-packet
847 Control the use of the remote protocol `QTBuffer:size' packet.
851 Control display of debugging messages related to ARM AArch64.
854 set debug coff-pe-read
855 show debug coff-pe-read
856 Control display of debugging messages related to reading of COFF/PE
861 Control display of debugging messages related to Mach-O symbols
864 set debug notification
865 show debug notification
866 Control display of debugging info for async remote notification.
870 ** Command parameter changes are now notified using new async record
871 "=cmd-param-changed".
872 ** Trace frame changes caused by command "tfind" are now notified using
873 new async record "=traceframe-changed".
874 ** The creation, deletion and modification of trace state variables
875 are now notified using new async records "=tsv-created",
876 "=tsv-deleted" and "=tsv-modified".
877 ** The start and stop of process record are now notified using new
878 async record "=record-started" and "=record-stopped".
879 ** Memory changes are now notified using new async record
881 ** The data-disassemble command response will include a "fullname" field
882 containing the absolute file name when source has been requested.
883 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
884 command, to allow pattern filling of memory areas.
885 ** New commands "-catch-load"/"-catch-unload" added for intercepting
886 library load/unload events.
887 ** The response to breakpoint commands and breakpoint async records
888 includes an "installed" field containing a boolean state about each
889 non-pending tracepoint location is whether installed on target or not.
890 ** Output of the "-trace-status" command includes a "trace-file" field
891 containing the name of the trace file being examined. This field is
892 optional, and only present when examining a trace file.
893 ** The "fullname" field is now always present along with the "file" field,
894 even if the file cannot be found by GDB.
896 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
897 You must have the LZMA library available when configuring GDB for this
898 feature to be enabled. For more information, see:
899 http://fedoraproject.org/wiki/Features/MiniDebugInfo
904 Set the size of trace buffer. The remote stub reports support for this
905 packet to gdb's qSupported query.
908 Enable Branch Trace Store (BTS)-based branch tracing for the current
909 thread. The remote stub reports support for this packet to gdb's
913 Disable branch tracing for the current thread. The remote stub reports
914 support for this packet to gdb's qSupported query.
917 Read the traced branches for the current thread. The remote stub
918 reports support for this packet to gdb's qSupported query.
920 *** Changes in GDB 7.5
922 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
923 for more x32 ABI info.
925 * GDB now supports access to MIPS DSP registers on Linux targets.
927 * GDB now supports debugging microMIPS binaries.
929 * The "info os" command on GNU/Linux can now display information on
930 several new classes of objects managed by the operating system:
931 "info os procgroups" lists process groups
932 "info os files" lists file descriptors
933 "info os sockets" lists internet-domain sockets
934 "info os shm" lists shared-memory regions
935 "info os semaphores" lists semaphores
936 "info os msg" lists message queues
937 "info os modules" lists loaded kernel modules
939 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
940 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
941 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
942 options and inspect the probe arguments using the new $_probe_arg family
943 of convenience variables. You can obtain more information about SystemTap
944 in <http://sourceware.org/systemtap/>.
946 * GDB now supports reversible debugging on ARM, it allows you to
947 debug basic ARM and THUMB instructions, and provides
948 record/replay support.
950 * The option "symbol-reloading" has been deleted as it is no longer used.
954 ** GDB commands implemented in Python can now be put in command class
957 ** The "maint set python print-stack on|off" is now deleted.
959 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
960 apply "flag enum"-style pretty-printing to any enum.
962 ** gdb.lookup_symbol can now work when there is no current frame.
964 ** gdb.Symbol now has a 'line' attribute, holding the line number in
965 the source at which the symbol was defined.
967 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
968 method 'value'. The former indicates whether the symbol needs a
969 frame in order to compute its value, and the latter computes the
972 ** A new method 'referenced_value' on gdb.Value objects which can
973 dereference pointer as well as C++ reference values.
975 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
976 which return the global and static blocks (as gdb.Block objects),
977 of the underlying symbol table, respectively.
979 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
980 object associated with a PC value.
982 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
983 of the address range occupied by code for the current source line.
985 * Go language support.
986 GDB now supports debugging programs written in the Go programming
989 * GDBserver now supports stdio connections.
990 E.g. (gdb) target remote | ssh myhost gdbserver - hello
992 * The binary "gdbtui" can no longer be built or installed.
993 Use "gdb -tui" instead.
995 * GDB will now print "flag" enums specially. A flag enum is one where
996 all the enumerator values have no bits in common when pairwise
997 "and"ed. When printing a value whose type is a flag enum, GDB will
998 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
999 (gdb) print (enum E) 3
1002 * The filename part of a linespec will now match trailing components
1003 of a source file name. For example, "break gcc/expr.c:1000" will
1004 now set a breakpoint in build/gcc/expr.c, but not
1005 build/libcpp/expr.c.
1007 * The "info proc" and "generate-core-file" commands will now also
1008 work on remote targets connected to GDBserver on Linux.
1010 * The command "info catch" has been removed. It has been disabled
1011 since December 2007.
1013 * The "catch exception" and "catch assert" commands now accept
1014 a condition at the end of the command, much like the "break"
1015 command does. For instance:
1017 (gdb) catch exception Constraint_Error if Barrier = True
1019 Previously, it was possible to add a condition to such catchpoints,
1020 but it had to be done as a second step, after the catchpoint had been
1021 created, using the "condition" command.
1023 * The "info static-tracepoint-marker" command will now also work on
1024 native Linux targets with in-process agent.
1026 * GDB can now set breakpoints on inlined functions.
1028 * The .gdb_index section has been updated to include symbols for
1029 inlined functions. GDB will ignore older .gdb_index sections by
1030 default, which could cause symbol files to be loaded more slowly
1031 until their .gdb_index sections can be recreated. The new command
1032 "set use-deprecated-index-sections on" will cause GDB to use any older
1033 .gdb_index sections it finds. This will restore performance, but the
1034 ability to set breakpoints on inlined functions will be lost in symbol
1035 files with older .gdb_index sections.
1037 The .gdb_index section has also been updated to record more information
1038 about each symbol. This speeds up the "info variables", "info functions"
1039 and "info types" commands when used with programs having the .gdb_index
1040 section, as well as speeding up debugging with shared libraries using
1041 the .gdb_index section.
1043 * Ada support for GDB/MI Variable Objects has been added.
1045 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1050 ** New command -info-os is the MI equivalent of "info os".
1052 ** Output logs ("set logging" and related) now include MI output.
1056 ** "set use-deprecated-index-sections on|off"
1057 "show use-deprecated-index-sections on|off"
1058 Controls the use of deprecated .gdb_index sections.
1060 ** "catch load" and "catch unload" can be used to stop when a shared
1061 library is loaded or unloaded, respectively.
1063 ** "enable count" can be used to auto-disable a breakpoint after
1066 ** "info vtbl" can be used to show the virtual method tables for
1067 C++ and Java objects.
1069 ** "explore" and its sub commands "explore value" and "explore type"
1070 can be used to recursively explore values and types of
1071 expressions. These commands are available only if GDB is
1072 configured with '--with-python'.
1074 ** "info auto-load" shows status of all kinds of auto-loaded files,
1075 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1076 sequences of commands files, "info auto-load python-scripts"
1077 shows status of auto-loading Python script files,
1078 "info auto-load local-gdbinit" shows status of loading init file
1079 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1080 status of inferior specific thread debugging shared library loading.
1082 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1083 and "show auto-load-scripts" commands have been deprecated, use their
1084 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1085 and "show auto-load python-scripts" counterparts instead.
1087 ** "dprintf location,format,args..." creates a dynamic printf, which
1088 is basically a breakpoint that does a printf and immediately
1089 resumes your program's execution, so it is like a printf that you
1090 can insert dynamically at runtime instead of at compiletime.
1092 ** "set print symbol"
1094 Controls whether GDB attempts to display the symbol, if any,
1095 corresponding to addresses it prints. This defaults to "on", but
1096 you can set it to "off" to restore GDB's previous behavior.
1098 * Deprecated commands
1100 ** For the Renesas Super-H architecture, the "regs" command has been
1101 deprecated, and "info all-registers" should be used instead.
1105 Renesas RL78 rl78-*-elf
1106 HP OpenVMS ia64 ia64-hp-openvms*
1108 * GDBserver supports evaluation of breakpoint conditions. When
1109 support is advertised by GDBserver, GDB may be told to send the
1110 breakpoint conditions in bytecode form to GDBserver. GDBserver
1111 will only report the breakpoint trigger to GDB when its condition
1116 set mips compression
1117 show mips compression
1118 Select the compressed ISA encoding used in functions that have no symbol
1119 information available. The encoding can be set to either of:
1122 and is updated automatically from ELF file flags if available.
1124 set breakpoint condition-evaluation
1125 show breakpoint condition-evaluation
1126 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1127 GDBserver ("target"). Default option "auto" chooses the most efficient
1129 This option can improve debugger efficiency depending on the speed of the
1133 Disable auto-loading globally.
1136 Show auto-loading setting of all kinds of auto-loaded files.
1138 set auto-load gdb-scripts on|off
1139 show auto-load gdb-scripts
1140 Control auto-loading of GDB canned sequences of commands files.
1142 set auto-load python-scripts on|off
1143 show auto-load python-scripts
1144 Control auto-loading of Python script files.
1146 set auto-load local-gdbinit on|off
1147 show auto-load local-gdbinit
1148 Control loading of init file (.gdbinit) from current directory.
1150 set auto-load libthread-db on|off
1151 show auto-load libthread-db
1152 Control auto-loading of inferior specific thread debugging shared library.
1154 set auto-load scripts-directory <dir1>[:<dir2>...]
1155 show auto-load scripts-directory
1156 Set a list of directories from which to load auto-loaded scripts.
1157 Automatically loaded Python scripts and GDB scripts are located in one
1158 of the directories listed by this option.
1159 The delimiter (':' above) may differ according to the host platform.
1161 set auto-load safe-path <dir1>[:<dir2>...]
1162 show auto-load safe-path
1163 Set a list of directories from which it is safe to auto-load files.
1164 The delimiter (':' above) may differ according to the host platform.
1166 set debug auto-load on|off
1167 show debug auto-load
1168 Control display of debugging info for auto-loading the files above.
1170 set dprintf-style gdb|call|agent
1172 Control the way in which a dynamic printf is performed; "gdb"
1173 requests a GDB printf command, while "call" causes dprintf to call a
1174 function in the inferior. "agent" requests that the target agent
1175 (such as GDBserver) do the printing.
1177 set dprintf-function <expr>
1178 show dprintf-function
1179 set dprintf-channel <expr>
1180 show dprintf-channel
1181 Set the function and optional first argument to the call when using
1182 the "call" style of dynamic printf.
1184 set disconnected-dprintf on|off
1185 show disconnected-dprintf
1186 Control whether agent-style dynamic printfs continue to be in effect
1187 after GDB disconnects.
1189 * New configure options
1191 --with-auto-load-dir
1192 Configure default value for the 'set auto-load scripts-directory'
1193 setting above. It defaults to '$debugdir:$datadir/auto-load',
1194 $debugdir representing global debugging info directories (available
1195 via 'show debug-file-directory') and $datadir representing GDB's data
1196 directory (available via 'show data-directory').
1198 --with-auto-load-safe-path
1199 Configure default value for the 'set auto-load safe-path' setting
1200 above. It defaults to the --with-auto-load-dir setting.
1202 --without-auto-load-safe-path
1203 Set 'set auto-load safe-path' to '/', effectively disabling this
1206 * New remote packets
1208 z0/z1 conditional breakpoints extension
1210 The z0/z1 breakpoint insertion packets have been extended to carry
1211 a list of conditional expressions over to the remote stub depending on the
1212 condition evaluation mode. The use of this extension can be controlled
1213 via the "set remote conditional-breakpoints-packet" command.
1217 Specify the signals which the remote stub may pass to the debugged
1218 program without GDB involvement.
1220 * New command line options
1222 --init-command=FILE, -ix Like --command, -x but execute it
1223 before loading inferior.
1224 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1225 execute it before loading inferior.
1227 *** Changes in GDB 7.4
1229 * GDB now handles ambiguous linespecs more consistently; the existing
1230 FILE:LINE support has been expanded to other types of linespecs. A
1231 breakpoint will now be set on all matching locations in all
1232 inferiors, and locations will be added or removed according to
1235 * GDB now allows you to skip uninteresting functions and files when
1236 stepping with the "skip function" and "skip file" commands.
1238 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1239 and "show remote hardware-watchpoint-length-limit". These allows to
1240 set or show the maximum length limit (in bytes) of a remote
1241 target hardware watchpoint.
1243 This allows e.g. to use "unlimited" hardware watchpoints with the
1244 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1245 watchpoints are slower than real hardware watchpoints but are
1246 significantly faster than gdb software watchpoints.
1250 ** The register_pretty_printer function in module gdb.printing now takes
1251 an optional `replace' argument. If True, the new printer replaces any
1254 ** The "maint set python print-stack on|off" command has been
1255 deprecated and will be deleted in GDB 7.5.
1256 A new command: "set python print-stack none|full|message" has
1257 replaced it. Additionally, the default for "print-stack" is
1258 now "message", which just prints the error message without
1261 ** A prompt substitution hook (prompt_hook) is now available to the
1264 ** A new Python module, gdb.prompt has been added to the GDB Python
1265 modules library. This module provides functionality for
1266 escape sequences in prompts (used by set/show
1267 extended-prompt). These escape sequences are replaced by their
1268 corresponding value.
1270 ** Python commands and convenience-functions located in
1271 'data-directory'/python/gdb/command and
1272 'data-directory'/python/gdb/function are now automatically loaded
1275 ** Blocks now provide four new attributes. global_block and
1276 static_block will return the global and static blocks
1277 respectively. is_static and is_global are boolean attributes
1278 that indicate if the block is one of those two types.
1280 ** Symbols now provide the "type" attribute, the type of the symbol.
1282 ** The "gdb.breakpoint" function has been deprecated in favor of
1285 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1286 of a function. This class is based on the "finish" command
1287 available in the CLI.
1289 ** Type objects for struct and union types now allow access to
1290 the fields using standard Python dictionary (mapping) methods.
1291 For example, "some_type['myfield']" now works, as does
1292 "some_type.items()".
1294 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1297 ** A new function, "deep_items" has been added to the gdb.types
1298 module in the GDB Python modules library. This function returns
1299 an iterator over the fields of a struct or union type. Unlike
1300 the standard Python "iteritems" method, it will recursively traverse
1301 any anonymous fields.
1305 ** "*stopped" events can report several new "reason"s, such as
1308 ** Breakpoint changes are now notified using new async records, like
1309 "=breakpoint-modified".
1311 ** New command -ada-task-info.
1313 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1314 $sdir specifies the default system locations of shared libraries.
1315 $pdir specifies the directory where the libpthread used by the application
1318 GDB no longer looks in $sdir and $pdir after it has searched the directories
1319 mentioned in libthread-db-search-path. If you want to search those
1320 directories, they must be specified in libthread-db-search-path.
1321 The default value of libthread-db-search-path on GNU/Linux and Solaris
1322 systems is now "$sdir:$pdir".
1324 $pdir is not supported by gdbserver, it is currently ignored.
1325 $sdir is supported by gdbserver.
1327 * New configure option --with-iconv-bin.
1328 When using the internationalization support like the one in the GNU C
1329 library, GDB will invoke the "iconv" program to get a list of supported
1330 character sets. If this program lives in a non-standard location, one can
1331 use this option to specify where to find it.
1333 * When natively debugging programs on PowerPC BookE processors running
1334 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1335 watchpoints, which specify a mask in addition to an address to watch.
1336 The mask specifies that some bits of an address (the bits which are
1337 reset in the mask) should be ignored when matching the address accessed
1338 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1339 section in the user manual for more details.
1341 * The new option --once causes GDBserver to stop listening for connections once
1342 the first connection is made. The listening port used by GDBserver will
1343 become available after that.
1345 * New commands "info macros" and "alias" have been added.
1347 * New function parameters suffix @entry specifies value of function parameter
1348 at the time the function got called. Entry values are available only since
1354 "!" is now an alias of the "shell" command.
1355 Note that no space is needed between "!" and SHELL COMMAND.
1359 watch EXPRESSION mask MASK_VALUE
1360 The watch command now supports the mask argument which allows creation
1361 of masked watchpoints, if the current architecture supports this feature.
1363 info auto-load-scripts [REGEXP]
1364 This command was formerly named "maintenance print section-scripts".
1365 It is now generally useful and is no longer a maintenance-only command.
1367 info macro [-all] [--] MACRO
1368 The info macro command has new options `-all' and `--'. The first for
1369 printing all definitions of a macro. The second for explicitly specifying
1370 the end of arguments and the beginning of the macro name in case the macro
1371 name starts with a hyphen.
1373 collect[/s] EXPRESSIONS
1374 The tracepoint collect command now takes an optional modifier "/s"
1375 that directs it to dereference pointer-to-character types and
1376 collect the bytes of memory up to a zero byte. The behavior is
1377 similar to what you see when you use the regular print command on a
1378 string. An optional integer following the "/s" sets a bound on the
1379 number of bytes that will be collected.
1382 The trace start command now interprets any supplied arguments as a
1383 note to be recorded with the trace run, with an effect similar to
1384 setting the variable trace-notes.
1387 The trace stop command now interprets any arguments as a note to be
1388 mentioned along with the tstatus report that the trace was stopped
1389 with a command. The effect is similar to setting the variable
1392 * Tracepoints can now be enabled and disabled at any time after a trace
1393 experiment has been started using the standard "enable" and "disable"
1394 commands. It is now possible to start a trace experiment with no enabled
1395 tracepoints; GDB will display a warning, but will allow the experiment to
1396 begin, assuming that tracepoints will be enabled as needed while the trace
1399 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1400 locations with 4-byte instructions, when they were previously
1401 limited to locations with instructions of 5 bytes or longer.
1405 set debug dwarf2-read
1406 show debug dwarf2-read
1407 Turns on or off display of debugging messages related to reading
1408 DWARF debug info. The default is off.
1410 set debug symtab-create
1411 show debug symtab-create
1412 Turns on or off display of debugging messages related to symbol table
1413 creation. The default is off.
1416 show extended-prompt
1417 Set the GDB prompt, and allow escape sequences to be inserted to
1418 display miscellaneous information (see 'help set extended-prompt'
1419 for the list of sequences). This prompt (and any information
1420 accessed through the escape sequences) is updated every time the
1421 prompt is displayed.
1423 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1424 show print entry-values
1425 Set printing of frame argument values at function entry. In some cases
1426 GDB can determine the value of function argument which was passed by the
1427 function caller, even if the value was modified inside the called function.
1429 set debug entry-values
1430 show debug entry-values
1431 Control display of debugging info for determining frame argument values at
1432 function entry and virtual tail call frames.
1434 set basenames-may-differ
1435 show basenames-may-differ
1436 Set whether a source file may have multiple base names.
1437 (A "base name" is the name of a file with the directory part removed.
1438 Example: The base name of "/home/user/hello.c" is "hello.c".)
1439 If set, GDB will canonicalize file names (e.g., expand symlinks)
1440 before comparing them. Canonicalization is an expensive operation,
1441 but it allows the same file be known by more than one base name.
1442 If not set (the default), all source files are assumed to have just
1443 one base name, and gdb will do file name comparisons more efficiently.
1449 Set a user name and notes for the current and any future trace runs.
1450 This is useful for long-running and/or disconnected traces, to
1451 inform others (or yourself) as to who is running the trace, supply
1452 contact information, or otherwise explain what is going on.
1454 set trace-stop-notes
1455 show trace-stop-notes
1456 Set a note attached to the trace run, that is displayed when the
1457 trace has been stopped by a tstop command. This is useful for
1458 instance as an explanation, if you are stopping a trace run that was
1459 started by someone else.
1461 * New remote packets
1465 Dynamically enable a tracepoint in a started trace experiment.
1469 Dynamically disable a tracepoint in a started trace experiment.
1473 Set the user and notes of the trace run.
1477 Query the current status of a tracepoint.
1481 Query the minimum length of instruction at which a fast tracepoint may
1484 * Dcache size (number of lines) and line-size are now runtime-configurable
1485 via "set dcache line" and "set dcache line-size" commands.
1489 Texas Instruments TMS320C6x tic6x-*-*
1493 Renesas RL78 rl78-*-elf
1495 *** Changes in GDB 7.3.1
1497 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1499 *** Changes in GDB 7.3
1501 * GDB has a new command: "thread find [REGEXP]".
1502 It finds the thread id whose name, target id, or thread extra info
1503 matches the given regular expression.
1505 * The "catch syscall" command now works on mips*-linux* targets.
1507 * The -data-disassemble MI command now supports modes 2 and 3 for
1508 dumping the instruction opcodes.
1510 * New command line options
1512 -data-directory DIR Specify DIR as the "data-directory".
1513 This is mostly for testing purposes.
1515 * The "maint set python auto-load on|off" command has been renamed to
1516 "set auto-load-scripts on|off".
1518 * GDB has a new command: "set directories".
1519 It is like the "dir" command except that it replaces the
1520 source path list instead of augmenting it.
1522 * GDB now understands thread names.
1524 On GNU/Linux, "info threads" will display the thread name as set by
1525 prctl or pthread_setname_np.
1527 There is also a new command, "thread name", which can be used to
1528 assign a name internally for GDB to display.
1531 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1532 has been integrated into GDB.
1536 ** The function gdb.Write now accepts an optional keyword 'stream'.
1537 This keyword, when provided, will direct the output to either
1538 stdout, stderr, or GDB's logging output.
1540 ** Parameters can now be be sub-classed in Python, and in particular
1541 you may implement the get_set_doc and get_show_doc functions.
1542 This improves how Parameter set/show documentation is processed
1543 and allows for more dynamic content.
1545 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1546 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1547 have an is_valid method.
1549 ** Breakpoints can now be sub-classed in Python, and in particular
1550 you may implement a 'stop' function that is executed each time
1551 the inferior reaches that breakpoint.
1553 ** New function gdb.lookup_global_symbol looks up a global symbol.
1555 ** GDB values in Python are now callable if the value represents a
1556 function. For example, if 'some_value' represents a function that
1557 takes two integer parameters and returns a value, you can call
1558 that function like so:
1560 result = some_value (10,20)
1562 ** Module gdb.types has been added.
1563 It contains a collection of utilities for working with gdb.Types objects:
1564 get_basic_type, has_field, make_enum_dict.
1566 ** Module gdb.printing has been added.
1567 It contains utilities for writing and registering pretty-printers.
1568 New classes: PrettyPrinter, SubPrettyPrinter,
1569 RegexpCollectionPrettyPrinter.
1570 New function: register_pretty_printer.
1572 ** New commands "info pretty-printers", "enable pretty-printer" and
1573 "disable pretty-printer" have been added.
1575 ** gdb.parameter("directories") is now available.
1577 ** New function gdb.newest_frame returns the newest frame in the
1580 ** The gdb.InferiorThread class has a new "name" attribute. This
1581 holds the thread's name.
1583 ** Python Support for Inferior events.
1584 Python scripts can add observers to be notified of events
1585 occurring in the process being debugged.
1586 The following events are currently supported:
1587 - gdb.events.cont Continue event.
1588 - gdb.events.exited Inferior exited event.
1589 - gdb.events.stop Signal received, and Breakpoint hit events.
1593 ** GDB now puts template parameters in scope when debugging in an
1594 instantiation. For example, if you have:
1596 template<int X> int func (void) { return X; }
1598 then if you step into func<5>, "print X" will show "5". This
1599 feature requires proper debuginfo support from the compiler; it
1600 was added to GCC 4.5.
1602 ** The motion commands "next", "finish", "until", and "advance" now
1603 work better when exceptions are thrown. In particular, GDB will
1604 no longer lose control of the inferior; instead, the GDB will
1605 stop the inferior at the point at which the exception is caught.
1606 This functionality requires a change in the exception handling
1607 code that was introduced in GCC 4.5.
1609 * GDB now follows GCC's rules on accessing volatile objects when
1610 reading or writing target state during expression evaluation.
1611 One notable difference to prior behavior is that "print x = 0"
1612 no longer generates a read of x; the value of the assignment is
1613 now always taken directly from the value being assigned.
1615 * GDB now has some support for using labels in the program's source in
1616 linespecs. For instance, you can use "advance label" to continue
1617 execution to a label.
1619 * GDB now has support for reading and writing a new .gdb_index
1620 section. This section holds a fast index of DWARF debugging
1621 information and can be used to greatly speed up GDB startup and
1622 operation. See the documentation for `save gdb-index' for details.
1624 * The "watch" command now accepts an optional "-location" argument.
1625 When used, this causes GDB to watch the memory referred to by the
1626 expression. Such a watchpoint is never deleted due to it going out
1629 * GDB now supports thread debugging of core dumps on GNU/Linux.
1631 GDB now activates thread debugging using the libthread_db library
1632 when debugging GNU/Linux core dumps, similarly to when debugging
1633 live processes. As a result, when debugging a core dump file, GDB
1634 is now able to display pthread_t ids of threads. For example, "info
1635 threads" shows the same output as when debugging the process when it
1636 was live. In earlier releases, you'd see something like this:
1639 * 1 LWP 6780 main () at main.c:10
1641 While now you see this:
1644 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1646 It is also now possible to inspect TLS variables when debugging core
1649 When debugging a core dump generated on a machine other than the one
1650 used to run GDB, you may need to point GDB at the correct
1651 libthread_db library with the "set libthread-db-search-path"
1652 command. See the user manual for more details on this command.
1654 * When natively debugging programs on PowerPC BookE processors running
1655 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1656 which stop execution of the inferior whenever it executes an instruction
1657 at any address within the specified range. See the "PowerPC Embedded"
1658 section in the user manual for more details.
1660 * New features in the GDB remote stub, GDBserver
1662 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1663 and i686 LynxOS (version 5.x).
1665 ** GDBserver is now supported on Blackfin Linux.
1667 * New native configurations
1669 ia64 HP-UX ia64-*-hpux*
1673 Analog Devices, Inc. Blackfin Processor bfin-*
1675 * Ada task switching is now supported on sparc-elf targets when
1676 debugging a program using the Ravenscar Profile. For more information,
1677 see the "Tasking Support when using the Ravenscar Profile" section
1678 in the GDB user manual.
1680 * Guile support was removed.
1682 * New features in the GNU simulator
1684 ** The --map-info flag lists all known core mappings.
1686 ** CFI flashes may be simulated via the "cfi" device.
1688 *** Changes in GDB 7.2
1690 * Shared library support for remote targets by default
1692 When GDB is configured for a generic, non-OS specific target, like
1693 for example, --target=arm-eabi or one of the many *-*-elf targets,
1694 GDB now queries remote stubs for loaded shared libraries using the
1695 `qXfer:libraries:read' packet. Previously, shared library support
1696 was always disabled for such configurations.
1700 ** Argument Dependent Lookup (ADL)
1702 In C++ ADL lookup directs function search to the namespaces of its
1703 arguments even if the namespace has not been imported.
1713 Here the compiler will search for `foo' in the namespace of 'b'
1714 and find A::foo. GDB now supports this. This construct is commonly
1715 used in the Standard Template Library for operators.
1717 ** Improved User Defined Operator Support
1719 In addition to member operators, GDB now supports lookup of operators
1720 defined in a namespace and imported with a `using' directive, operators
1721 defined in the global scope, operators imported implicitly from an
1722 anonymous namespace, and the ADL operators mentioned in the previous
1724 GDB now also supports proper overload resolution for all the previously
1725 mentioned flavors of operators.
1727 ** static const class members
1729 Printing of static const class members that are initialized in the
1730 class definition has been fixed.
1732 * Windows Thread Information Block access.
1734 On Windows targets, GDB now supports displaying the Windows Thread
1735 Information Block (TIB) structure. This structure is visible either
1736 by using the new command `info w32 thread-information-block' or, by
1737 dereferencing the new convenience variable named `$_tlb', a
1738 thread-specific pointer to the TIB. This feature is also supported
1739 when remote debugging using GDBserver.
1741 * Static tracepoints
1743 Static tracepoints are calls in the user program into a tracing
1744 library. One such library is a port of the LTTng kernel tracer to
1745 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1746 When debugging with GDBserver, GDB now supports combining the GDB
1747 tracepoint machinery with such libraries. For example: the user can
1748 use GDB to probe a static tracepoint marker (a call from the user
1749 program into the tracing library) with the new "strace" command (see
1750 "New commands" below). This creates a "static tracepoint" in the
1751 breakpoint list, that can be manipulated with the same feature set
1752 as fast and regular tracepoints. E.g., collect registers, local and
1753 global variables, collect trace state variables, and define
1754 tracepoint conditions. In addition, the user can collect extra
1755 static tracepoint marker specific data, by collecting the new
1756 $_sdata internal variable. When analyzing the trace buffer, you can
1757 inspect $_sdata like any other variable available to GDB. For more
1758 information, see the "Tracepoints" chapter in GDB user manual. New
1759 remote packets have been defined to support static tracepoints, see
1760 the "New remote packets" section below.
1762 * Better reconstruction of tracepoints after disconnected tracing
1764 GDB will attempt to download the original source form of tracepoint
1765 definitions when starting a trace run, and then will upload these
1766 upon reconnection to the target, resulting in a more accurate
1767 reconstruction of the tracepoints that are in use on the target.
1771 You can now exercise direct control over the ways that GDB can
1772 affect your program. For instance, you can disallow the setting of
1773 breakpoints, so that the program can run continuously (assuming
1774 non-stop mode). In addition, the "observer" variable is available
1775 to switch all of the different controls; in observer mode, GDB
1776 cannot affect the target's behavior at all, which is useful for
1777 tasks like diagnosing live systems in the field.
1779 * The new convenience variable $_thread holds the number of the
1782 * New remote packets
1786 Return the address of the Windows Thread Information Block of a given thread.
1790 In response to several of the tracepoint packets, the target may now
1791 also respond with a number of intermediate `qRelocInsn' request
1792 packets before the final result packet, to have GDB handle
1793 relocating an instruction to execute at a different address. This
1794 is particularly useful for stubs that support fast tracepoints. GDB
1795 reports support for this feature in the qSupported packet.
1799 List static tracepoint markers in the target program.
1803 List static tracepoint markers at a given address in the target
1806 qXfer:statictrace:read
1808 Read the static trace data collected (by a `collect $_sdata'
1809 tracepoint action). The remote stub reports support for this packet
1810 to gdb's qSupported query.
1814 Send the current settings of GDB's permission flags.
1818 Send part of the source (textual) form of a tracepoint definition,
1819 which includes location, conditional, and action list.
1821 * The source command now accepts a -s option to force searching for the
1822 script in the source search path even if the script name specifies
1825 * New features in the GDB remote stub, GDBserver
1827 - GDBserver now support tracepoints (including fast tracepoints, and
1828 static tracepoints). The feature is currently supported by the
1829 i386-linux and amd64-linux builds. See the "Tracepoints support
1830 in gdbserver" section in the manual for more information.
1832 GDBserver JIT compiles the tracepoint's conditional agent
1833 expression bytecode into native code whenever possible for low
1834 overhead dynamic tracepoints conditionals. For such tracepoints,
1835 an expression that examines program state is evaluated when the
1836 tracepoint is reached, in order to determine whether to capture
1837 trace data. If the condition is simple and false, processing the
1838 tracepoint finishes very quickly and no data is gathered.
1840 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1841 for static tracepoints support.
1843 - GDBserver now supports x86_64 Windows 64-bit debugging.
1845 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1846 it understands register description.
1848 * The --batch flag now disables pagination and queries.
1850 * X86 general purpose registers
1852 GDB now supports reading/writing byte, word and double-word x86
1853 general purpose registers directly. This means you can use, say,
1854 $ah or $ax to refer, respectively, to the byte register AH and
1855 16-bit word register AX that are actually portions of the 32-bit
1856 register EAX or 64-bit register RAX.
1858 * The `commands' command now accepts a range of breakpoints to modify.
1859 A plain `commands' following a command that creates multiple
1860 breakpoints affects all the breakpoints set by that command. This
1861 applies to breakpoints set by `rbreak', and also applies when a
1862 single `break' command creates multiple breakpoints (e.g.,
1863 breakpoints on overloaded c++ functions).
1865 * The `rbreak' command now accepts a filename specification as part of
1866 its argument, limiting the functions selected by the regex to those
1867 in the specified file.
1869 * Support for remote debugging Windows and SymbianOS shared libraries
1870 from Unix hosts has been improved. Non Windows GDB builds now can
1871 understand target reported file names that follow MS-DOS based file
1872 system semantics, such as file names that include drive letters and
1873 use the backslash character as directory separator. This makes it
1874 possible to transparently use the "set sysroot" and "set
1875 solib-search-path" on Unix hosts to point as host copies of the
1876 target's shared libraries. See the new command "set
1877 target-file-system-kind" described below, and the "Commands to
1878 specify files" section in the user manual for more information.
1882 eval template, expressions...
1883 Convert the values of one or more expressions under the control
1884 of the string template to a command line, and call it.
1886 set target-file-system-kind unix|dos-based|auto
1887 show target-file-system-kind
1888 Set or show the assumed file system kind for target reported file
1891 save breakpoints <filename>
1892 Save all current breakpoint definitions to a file suitable for use
1893 in a later debugging session. To read the saved breakpoint
1894 definitions, use the `source' command.
1896 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1899 info static-tracepoint-markers
1900 Display information about static tracepoint markers in the target.
1902 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1903 Define a static tracepoint by probing a marker at the given
1904 function, line, address, or marker ID.
1908 Enable and disable observer mode.
1910 set may-write-registers on|off
1911 set may-write-memory on|off
1912 set may-insert-breakpoints on|off
1913 set may-insert-tracepoints on|off
1914 set may-insert-fast-tracepoints on|off
1915 set may-interrupt on|off
1916 Set individual permissions for GDB effects on the target. Note that
1917 some of these settings can have undesirable or surprising
1918 consequences, particularly when changed in the middle of a session.
1919 For instance, disabling the writing of memory can prevent
1920 breakpoints from being inserted, cause single-stepping to fail, or
1921 even crash your program, if you disable after breakpoints have been
1922 inserted. However, GDB should not crash.
1924 set record memory-query on|off
1925 show record memory-query
1926 Control whether to stop the inferior if memory changes caused
1927 by an instruction cannot be recorded.
1932 The disassemble command now supports "start,+length" form of two arguments.
1936 ** GDB now provides a new directory location, called the python directory,
1937 where Python scripts written for GDB can be installed. The location
1938 of that directory is <data-directory>/python, where <data-directory>
1939 is the GDB data directory. For more details, see section `Scripting
1940 GDB using Python' in the manual.
1942 ** The GDB Python API now has access to breakpoints, symbols, symbol
1943 tables, program spaces, inferiors, threads and frame's code blocks.
1944 Additionally, GDB Parameters can now be created from the API, and
1945 manipulated via set/show in the CLI.
1947 ** New functions gdb.target_charset, gdb.target_wide_charset,
1948 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1950 ** New exception gdb.GdbError.
1952 ** Pretty-printers are now also looked up in the current program space.
1954 ** Pretty-printers can now be individually enabled and disabled.
1956 ** GDB now looks for names of Python scripts to auto-load in a
1957 special section named `.debug_gdb_scripts', in addition to looking
1958 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1960 * Tracepoint actions were unified with breakpoint commands. In particular,
1961 there are no longer differences in "info break" output for breakpoints and
1962 tracepoints and the "commands" command can be used for both tracepoints and
1963 regular breakpoints.
1967 ARM Symbian arm*-*-symbianelf*
1969 * D language support.
1970 GDB now supports debugging programs written in the D programming
1973 * GDB now supports the extended ptrace interface for PowerPC which is
1974 available since Linux kernel version 2.6.34. This automatically enables
1975 any hardware breakpoints and additional hardware watchpoints available in
1976 the processor. The old ptrace interface exposes just one hardware
1977 watchpoint and no hardware breakpoints.
1979 * GDB is now able to use the Data Value Compare (DVC) register available on
1980 embedded PowerPC processors to implement in hardware simple watchpoint
1981 conditions of the form:
1983 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1985 This works in native GDB running on Linux kernels with the extended ptrace
1986 interface mentioned above.
1988 *** Changes in GDB 7.1
1992 ** Namespace Support
1994 GDB now supports importing of namespaces in C++. This enables the
1995 user to inspect variables from imported namespaces. Support for
1996 namepace aliasing has also been added. So, if a namespace is
1997 aliased in the current scope (e.g. namepace C=A; ) the user can
1998 print variables using the alias (e.g. (gdb) print C::x).
2002 All known bugs relating to the printing of virtual base class were
2003 fixed. It is now possible to call overloaded static methods using a
2008 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2009 and reinterpret_cast<> are now handled by the C++ expression parser.
2013 Xilinx MicroBlaze microblaze-*-*
2018 Xilinx MicroBlaze microblaze
2021 * Multi-program debugging.
2023 GDB now has support for multi-program (a.k.a. multi-executable or
2024 multi-exec) debugging. This allows for debugging multiple inferiors
2025 simultaneously each running a different program under the same GDB
2026 session. See "Debugging Multiple Inferiors and Programs" in the
2027 manual for more information. This implied some user visible changes
2028 in the multi-inferior support. For example, "info inferiors" now
2029 lists inferiors that are not running yet or that have exited
2030 already. See also "New commands" and "New options" below.
2032 * New tracing features
2034 GDB's tracepoint facility now includes several new features:
2036 ** Trace state variables
2038 GDB tracepoints now include support for trace state variables, which
2039 are variables managed by the target agent during a tracing
2040 experiment. They are useful for tracepoints that trigger each
2041 other, so for instance one tracepoint can count hits in a variable,
2042 and then a second tracepoint has a condition that is true when the
2043 count reaches a particular value. Trace state variables share the
2044 $-syntax of GDB convenience variables, and can appear in both
2045 tracepoint actions and condition expressions. Use the "tvariable"
2046 command to create, and "info tvariables" to view; see "Trace State
2047 Variables" in the manual for more detail.
2051 GDB now includes an option for defining fast tracepoints, which
2052 targets may implement more efficiently, such as by installing a jump
2053 into the target agent rather than a trap instruction. The resulting
2054 speedup can be by two orders of magnitude or more, although the
2055 tradeoff is that some program locations on some target architectures
2056 might not allow fast tracepoint installation, for instance if the
2057 instruction to be replaced is shorter than the jump. To request a
2058 fast tracepoint, use the "ftrace" command, with syntax identical to
2059 the regular trace command.
2061 ** Disconnected tracing
2063 It is now possible to detach GDB from the target while it is running
2064 a trace experiment, then reconnect later to see how the experiment
2065 is going. In addition, a new variable disconnected-tracing lets you
2066 tell the target agent whether to continue running a trace if the
2067 connection is lost unexpectedly.
2071 GDB now has the ability to save the trace buffer into a file, and
2072 then use that file as a target, similarly to you can do with
2073 corefiles. You can select trace frames, print data that was
2074 collected in them, and use tstatus to display the state of the
2075 tracing run at the moment that it was saved. To create a trace
2076 file, use "tsave <filename>", and to use it, do "target tfile
2079 ** Circular trace buffer
2081 You can ask the target agent to handle the trace buffer as a
2082 circular buffer, discarding the oldest trace frames to make room for
2083 newer ones, by setting circular-trace-buffer to on. This feature may
2084 not be available for all target agents.
2089 The disassemble command, when invoked with two arguments, now requires
2090 the arguments to be comma-separated.
2093 The info variables command now displays variable definitions. Files
2094 which only declare a variable are not shown.
2097 The source command is now capable of sourcing Python scripts.
2098 This feature is dependent on the debugger being build with Python
2101 Related to this enhancement is also the introduction of a new command
2102 "set script-extension" (see below).
2104 * New commands (for set/show, see "New options" below)
2106 record save [<FILENAME>]
2107 Save a file (in core file format) containing the process record
2108 execution log for replay debugging at a later time.
2110 record restore <FILENAME>
2111 Restore the process record execution log that was saved at an
2112 earlier time, for replay debugging.
2114 add-inferior [-copies <N>] [-exec <FILENAME>]
2117 clone-inferior [-copies <N>] [ID]
2118 Make a new inferior ready to execute the same program another
2119 inferior has loaded.
2124 maint info program-spaces
2125 List the program spaces loaded into GDB.
2127 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2128 show remote interrupt-sequence
2129 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2130 as the sequence to the remote target in order to interrupt the execution.
2131 Ctrl-C is a default. Some system prefers BREAK which is high level of
2132 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2133 Magic SysRq g. It is BREAK signal and character 'g'.
2135 set remote interrupt-on-connect [on | off]
2136 show remote interrupt-on-connect
2137 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2138 remote target when gdb connects to it. This is needed when you debug
2141 set remotebreak [on | off]
2143 Deprecated. Use "set/show remote interrupt-sequence" instead.
2145 tvariable $NAME [ = EXP ]
2146 Create or modify a trace state variable.
2149 List trace state variables and their values.
2151 delete tvariable $NAME ...
2152 Delete one or more trace state variables.
2155 Evaluate the given expressions without collecting anything into the
2156 trace buffer. (Valid in tracepoint actions only.)
2158 ftrace FN / FILE:LINE / *ADDR
2159 Define a fast tracepoint at the given function, line, or address.
2161 * New expression syntax
2163 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2164 GDB now parses 0b101010 identically with 42.
2168 set follow-exec-mode new|same
2169 show follow-exec-mode
2170 Control whether GDB reuses the same inferior across an exec call or
2171 creates a new one. This is useful to be able to restart the old
2172 executable after the inferior having done an exec call.
2174 set default-collect EXPR, ...
2175 show default-collect
2176 Define a list of expressions to be collected at each tracepoint.
2177 This is a useful way to ensure essential items are not overlooked,
2178 such as registers or a critical global variable.
2180 set disconnected-tracing
2181 show disconnected-tracing
2182 If set to 1, the target is instructed to continue tracing if it
2183 loses its connection to GDB. If 0, the target is to stop tracing
2186 set circular-trace-buffer
2187 show circular-trace-buffer
2188 If set to on, the target is instructed to use a circular trace buffer
2189 and discard the oldest trace frames instead of stopping the trace due
2190 to a full trace buffer. If set to off, the trace stops when the buffer
2191 fills up. Some targets may not support this.
2193 set script-extension off|soft|strict
2194 show script-extension
2195 If set to "off", the debugger does not perform any script language
2196 recognition, and all sourced files are assumed to be GDB scripts.
2197 If set to "soft" (the default), files are sourced according to
2198 filename extension, falling back to GDB scripts if the first
2200 If set to "strict", files are sourced according to filename extension.
2202 set ada trust-PAD-over-XVS on|off
2203 show ada trust-PAD-over-XVS
2204 If off, activate a workaround against a bug in the debugging information
2205 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2206 the GCC sources for more information about the GNAT encoding and
2207 PAD types in particular). It is always safe to set this option to
2208 off, but this introduces a slight performance penalty. The default
2211 * Python API Improvements
2213 ** GDB provides the new class gdb.LazyString. This is useful in
2214 some pretty-printing cases. The new method gdb.Value.lazy_string
2215 provides a simple way to create objects of this type.
2217 ** The fields returned by gdb.Type.fields now have an
2218 `is_base_class' attribute.
2220 ** The new method gdb.Type.range returns the range of an array type.
2222 ** The new method gdb.parse_and_eval can be used to parse and
2223 evaluate an expression.
2225 * New remote packets
2228 Define a trace state variable.
2231 Get the current value of a trace state variable.
2234 Set desired tracing behavior upon disconnection.
2237 Set the trace buffer to be linear or circular.
2240 Get data about the tracepoints currently in use.
2244 Process record now works correctly with hardware watchpoints.
2246 Multiple bug fixes have been made to the mips-irix port, making it
2247 much more reliable. In particular:
2248 - Debugging threaded applications is now possible again. Previously,
2249 GDB would hang while starting the program, or while waiting for
2250 the program to stop at a breakpoint.
2251 - Attaching to a running process no longer hangs.
2252 - An error occurring while loading a core file has been fixed.
2253 - Changing the value of the PC register now works again. This fixes
2254 problems observed when using the "jump" command, or when calling
2255 a function from GDB, or even when assigning a new value to $pc.
2256 - With the "finish" and "return" commands, the return value for functions
2257 returning a small array is now correctly printed.
2258 - It is now possible to break on shared library code which gets executed
2259 during a shared library init phase (code executed while executing
2260 their .init section). Previously, the breakpoint would have no effect.
2261 - GDB is now able to backtrace through the signal handler for
2262 non-threaded programs.
2264 PIE (Position Independent Executable) programs debugging is now supported.
2265 This includes debugging execution of PIC (Position Independent Code) shared
2266 libraries although for that, it should be possible to run such libraries as an
2269 *** Changes in GDB 7.0
2271 * GDB now has an interface for JIT compilation. Applications that
2272 dynamically generate code can create symbol files in memory and register
2273 them with GDB. For users, the feature should work transparently, and
2274 for JIT developers, the interface is documented in the GDB manual in the
2275 "JIT Compilation Interface" chapter.
2277 * Tracepoints may now be conditional. The syntax is as for
2278 breakpoints; either an "if" clause appended to the "trace" command,
2279 or the "condition" command is available. GDB sends the condition to
2280 the target for evaluation using the same bytecode format as is used
2281 for tracepoint actions.
2283 * The disassemble command now supports: an optional /r modifier, print the
2284 raw instructions in hex as well as in symbolic form, and an optional /m
2285 modifier to print mixed source+assembly.
2287 * Process record and replay
2289 In a architecture environment that supports ``process record and
2290 replay'', ``process record and replay'' target can record a log of
2291 the process execution, and replay it with both forward and reverse
2294 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2295 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2296 set execution-direction {forward|reverse}, for targets that support
2299 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2300 feature is available with a native GDB running on kernel version
2303 * GDB now has support for multi-byte and wide character sets on the
2304 target. Strings whose character type is wchar_t, char16_t, or
2305 char32_t are now correctly printed. GDB supports wide- and unicode-
2306 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2307 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2308 `printf'. This feature requires iconv to work properly; if your
2309 system does not have a working iconv, GDB can use GNU libiconv. See
2310 the installation instructions for more information.
2312 * GDB now supports automatic retrieval of shared library files from
2313 remote targets. To use this feature, specify a system root that begins
2314 with the `remote:' prefix, either via the `set sysroot' command or via
2315 the `--with-sysroot' configure-time option.
2317 * "info sharedlibrary" now takes an optional regex of libraries to show,
2318 and it now reports if a shared library has no debugging information.
2320 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2321 now complete on file names.
2323 * When completing in expressions, gdb will attempt to limit
2324 completions to allowable structure or union fields, where appropriate.
2325 For instance, consider:
2327 # struct example { int f1; double f2; };
2328 # struct example variable;
2331 If the user types TAB at the end of this command line, the available
2332 completions will be "f1" and "f2".
2334 * Inlined functions are now supported. They show up in backtraces, and
2335 the "step", "next", and "finish" commands handle them automatically.
2337 * GDB now supports the token-splicing (##) and stringification (#)
2338 operators when expanding macros. It also supports variable-arity
2341 * GDB now supports inspecting extra signal information, exported by
2342 the new $_siginfo convenience variable. The feature is currently
2343 implemented on linux ARM, i386 and amd64.
2345 * GDB can now display the VFP floating point registers and NEON vector
2346 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2347 can provide these registers (requires Linux 2.6.30 or later). Remote
2348 and simulator targets may also provide them.
2350 * New remote packets
2353 Search memory for a sequence of bytes.
2356 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2357 operation over reliable transport links. Use of this packet is
2358 controlled by the `set remote noack-packet' command.
2361 Kill the process with the specified process ID. Use this in preference
2362 to `k' when multiprocess protocol extensions are supported.
2365 Obtains additional operating system information
2369 Read or write additional signal information.
2371 * Removed remote protocol undocumented extension
2373 An undocumented extension to the remote protocol's `S' stop reply
2374 packet that permited the stub to pass a process id was removed.
2375 Remote servers should use the `T' stop reply packet instead.
2377 * GDB now supports multiple function calling conventions according to the
2378 DWARF-2 DW_AT_calling_convention function attribute.
2380 * The SH target utilizes the aforementioned change to distinguish between gcc
2381 and Renesas calling convention. It also adds the new CLI commands
2382 `set/show sh calling-convention'.
2384 * GDB can now read compressed debug sections, as produced by GNU gold
2385 with the --compress-debug-sections=zlib flag.
2387 * 64-bit core files are now supported on AIX.
2389 * Thread switching is now supported on Tru64.
2391 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2392 which will be allocated using malloc later in program execution.
2394 * The qXfer:libraries:read remote procotol packet now allows passing a
2395 list of section offsets.
2397 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2398 conditions handling signals delivered during attach or thread creation
2399 have also been fixed.
2401 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2402 From the user's standpoint, all unqualified instances of True and False
2403 are treated as the standard definitions, regardless of context.
2405 * GDB now parses C++ symbol and type names more flexibly. For
2408 template<typename T> class C { };
2411 GDB will now correctly handle all of:
2413 ptype C<char const *>
2414 ptype C<char const*>
2415 ptype C<const char *>
2416 ptype C<const char*>
2418 * New features in the GDB remote stub, gdbserver
2420 - The "--wrapper" command-line argument tells gdbserver to use a
2421 wrapper program to launch programs for debugging.
2423 - On PowerPC and S/390 targets, it is now possible to use a single
2424 gdbserver executable to debug both 32-bit and 64-bit programs.
2425 (This requires gdbserver itself to be built as a 64-bit executable.)
2427 - gdbserver uses the new noack protocol mode for TCP connections to
2428 reduce communications latency, if also supported and enabled in GDB.
2430 - Support for the sparc64-linux-gnu target is now included in
2433 - The amd64-linux build of gdbserver now supports debugging both
2434 32-bit and 64-bit programs.
2436 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2437 now support hardware watchpoints, and will use them automatically
2442 GDB now has support for scripting using Python. Whether this is
2443 available is determined at configure time.
2445 New GDB commands can now be written in Python.
2447 * Ada tasking support
2449 Ada tasks can now be inspected in GDB. The following commands have
2453 Print the list of Ada tasks.
2455 Print detailed information about task number N.
2457 Print the task number of the current task.
2459 Switch the context of debugging to task number N.
2461 * Support for user-defined prefixed commands. The "define" command can
2462 add new commands to existing prefixes, e.g. "target".
2464 * Multi-inferior, multi-process debugging.
2466 GDB now has generalized support for multi-inferior debugging. See
2467 "Debugging Multiple Inferiors" in the manual for more information.
2468 Although availability still depends on target support, the command
2469 set is more uniform now. The GNU/Linux specific multi-forks support
2470 has been migrated to this new framework. This implied some user
2471 visible changes; see "New commands" and also "Removed commands"
2474 * Target descriptions can now describe the target OS ABI. See the
2475 "Target Description Format" section in the user manual for more
2478 * Target descriptions can now describe "compatible" architectures
2479 to indicate that the target can execute applications for a different
2480 architecture in addition to those for the main target architecture.
2481 See the "Target Description Format" section in the user manual for
2484 * Multi-architecture debugging.
2486 GDB now includes general supports for debugging applications on
2487 hybrid systems that use more than one single processor architecture
2488 at the same time. Each such hybrid architecture still requires
2489 specific support to be added. The only hybrid architecture supported
2490 in this version of GDB is the Cell Broadband Engine.
2492 * GDB now supports integrated debugging of Cell/B.E. applications that
2493 use both the PPU and SPU architectures. To enable support for hybrid
2494 Cell/B.E. debugging, you need to configure GDB to support both the
2495 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2496 --enable-targets configure option.
2498 * Non-stop mode debugging.
2500 For some targets, GDB now supports an optional mode of operation in
2501 which you can examine stopped threads while other threads continue
2502 to execute freely. This is referred to as non-stop mode, with the
2503 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2504 section in the user manual for more information.
2506 To be able to support remote non-stop debugging, a remote stub needs
2507 to implement the non-stop mode remote protocol extensions, as
2508 described in the "Remote Non-Stop" section of the user manual. The
2509 GDB remote stub, gdbserver, has been adjusted to support these
2510 extensions on linux targets.
2512 * New commands (for set/show, see "New options" below)
2514 catch syscall [NAME(S) | NUMBER(S)]
2515 Catch system calls. Arguments, which should be names of system
2516 calls or their numbers, mean catch only those syscalls. Without
2517 arguments, every syscall will be caught. When the inferior issues
2518 any of the specified syscalls, GDB will stop and announce the system
2519 call, both when it is called and when its call returns. This
2520 feature is currently available with a native GDB running on the
2521 Linux Kernel, under the following architectures: x86, x86_64,
2522 PowerPC and PowerPC64.
2524 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2526 Search memory for a sequence of bytes.
2528 maint set python print-stack
2529 maint show python print-stack
2530 Show a stack trace when an error is encountered in a Python script.
2533 Invoke CODE by passing it to the Python interpreter.
2538 These allow macros to be defined, undefined, and listed
2542 Show operating system information about processes.
2545 List the inferiors currently under GDB's control.
2548 Switch focus to inferior number NUM.
2551 Detach from inferior number NUM.
2554 Kill inferior number NUM.
2558 set spu stop-on-load
2559 show spu stop-on-load
2560 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2562 set spu auto-flush-cache
2563 show spu auto-flush-cache
2564 Control whether to automatically flush the software-managed cache
2565 during Cell/B.E. debugging.
2567 set sh calling-convention
2568 show sh calling-convention
2569 Control the calling convention used when calling SH target functions.
2572 show debug timestamp
2573 Control display of timestamps with GDB debugging output.
2575 set disassemble-next-line
2576 show disassemble-next-line
2577 Control display of disassembled source lines or instructions when
2580 set remote noack-packet
2581 show remote noack-packet
2582 Set/show the use of remote protocol QStartNoAckMode packet. See above
2583 under "New remote packets."
2585 set remote query-attached-packet
2586 show remote query-attached-packet
2587 Control use of remote protocol `qAttached' (query-attached) packet.
2589 set remote read-siginfo-object
2590 show remote read-siginfo-object
2591 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2594 set remote write-siginfo-object
2595 show remote write-siginfo-object
2596 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2599 set remote reverse-continue
2600 show remote reverse-continue
2601 Control use of remote protocol 'bc' (reverse-continue) packet.
2603 set remote reverse-step
2604 show remote reverse-step
2605 Control use of remote protocol 'bs' (reverse-step) packet.
2607 set displaced-stepping
2608 show displaced-stepping
2609 Control displaced stepping mode. Displaced stepping is a way to
2610 single-step over breakpoints without removing them from the debuggee.
2611 Also known as "out-of-line single-stepping".
2614 show debug displaced
2615 Control display of debugging info for displaced stepping.
2617 maint set internal-error
2618 maint show internal-error
2619 Control what GDB does when an internal error is detected.
2621 maint set internal-warning
2622 maint show internal-warning
2623 Control what GDB does when an internal warning is detected.
2628 Use a wrapper program to launch programs for debugging.
2630 set multiple-symbols (all|ask|cancel)
2631 show multiple-symbols
2632 The value of this variable can be changed to adjust the debugger behavior
2633 when an expression or a breakpoint location contains an ambiguous symbol
2634 name (an overloaded function name, for instance).
2636 set breakpoint always-inserted
2637 show breakpoint always-inserted
2638 Keep breakpoints always inserted in the target, as opposed to inserting
2639 them when resuming the target, and removing them when the target stops.
2640 This option can improve debugger performance on slow remote targets.
2642 set arm fallback-mode (arm|thumb|auto)
2643 show arm fallback-mode
2644 set arm force-mode (arm|thumb|auto)
2646 These commands control how ARM GDB determines whether instructions
2647 are ARM or Thumb. The default for both settings is auto, which uses
2648 the current CPSR value for instructions without symbols; previous
2649 versions of GDB behaved as if "set arm fallback-mode arm".
2651 set disable-randomization
2652 show disable-randomization
2653 Standalone programs run with the virtual address space randomization enabled
2654 by default on some platforms. This option keeps the addresses stable across
2655 multiple debugging sessions.
2659 Control whether other threads are stopped or not when some thread hits
2664 Requests that asynchronous execution is enabled in the target, if available.
2665 In this case, it's possible to resume target in the background, and interact
2666 with GDB while the target is running. "show target-async" displays the
2667 current state of asynchronous execution of the target.
2669 set target-wide-charset
2670 show target-wide-charset
2671 The target-wide-charset is the name of the character set that GDB
2672 uses when printing characters whose type is wchar_t.
2674 set tcp auto-retry (on|off)
2676 set tcp connect-timeout
2677 show tcp connect-timeout
2678 These commands allow GDB to retry failed TCP connections to a remote stub
2679 with a specified timeout period; this is useful if the stub is launched
2680 in parallel with GDB but may not be ready to accept connections immediately.
2682 set libthread-db-search-path
2683 show libthread-db-search-path
2684 Control list of directories which GDB will search for appropriate
2687 set schedule-multiple (on|off)
2688 show schedule-multiple
2689 Allow GDB to resume all threads of all processes or only threads of
2690 the current process.
2694 Use more aggressive caching for accesses to the stack. This improves
2695 performance of remote debugging (particularly backtraces) without
2696 affecting correctness.
2698 set interactive-mode (on|off|auto)
2699 show interactive-mode
2700 Control whether GDB runs in interactive mode (on) or not (off).
2701 When in interactive mode, GDB waits for the user to answer all
2702 queries. Otherwise, GDB does not wait and assumes the default
2703 answer. When set to auto (the default), GDB determines which
2704 mode to use based on the stdin settings.
2709 For program forks, this is replaced by the new more generic `info
2710 inferiors' command. To list checkpoints, you can still use the
2711 `info checkpoints' command, which was an alias for the `info forks'
2715 Replaced by the new `inferior' command. To switch between
2716 checkpoints, you can still use the `restart' command, which was an
2717 alias for the `fork' command.
2720 This is removed, since some targets don't have a notion of
2721 processes. To switch between processes, you can still use the
2722 `inferior' command using GDB's own inferior number.
2725 For program forks, this is replaced by the new more generic `kill
2726 inferior' command. To delete a checkpoint, you can still use the
2727 `delete checkpoint' command, which was an alias for the `delete
2731 For program forks, this is replaced by the new more generic `detach
2732 inferior' command. To detach a checkpoint, you can still use the
2733 `detach checkpoint' command, which was an alias for the `detach
2736 * New native configurations
2738 x86/x86_64 Darwin i[34567]86-*-darwin*
2740 x86_64 MinGW x86_64-*-mingw*
2744 Lattice Mico32 lm32-*
2745 x86 DICOS i[34567]86-*-dicos*
2746 x86_64 DICOS x86_64-*-dicos*
2749 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2750 (mingw32ce) debugging.
2756 These commands were actually not implemented on any target.
2758 *** Changes in GDB 6.8
2760 * New native configurations
2762 NetBSD/hppa hppa*-*netbsd*
2763 Xtensa GNU/Linux xtensa*-*-linux*
2767 NetBSD/hppa hppa*-*-netbsd*
2768 Xtensa GNU/Lunux xtensa*-*-linux*
2770 * Change in command line behavior -- corefiles vs. process ids.
2772 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2773 attaching to process NUMBER fails, GDB no longer attempts to open a
2774 core file named NUMBER. Attaching to a program using the -c option
2775 is no longer supported. Instead, use the '-p' or '--pid' options.
2777 * GDB can now be built as a native debugger for debugging Windows x86
2778 (mingw32) Portable Executable (PE) programs.
2780 * Pending breakpoints no longer change their number when their address
2783 * GDB now supports breakpoints with multiple locations,
2784 including breakpoints on C++ constructors, inside C++ templates,
2785 and in inlined functions.
2787 * GDB's ability to debug optimized code has been improved. GDB more
2788 accurately identifies function bodies and lexical blocks that occupy
2789 more than one contiguous range of addresses.
2791 * Target descriptions can now describe registers for PowerPC.
2793 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2794 registers on PowerPC targets.
2796 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2797 targets even when the libthread_db library is not available.
2799 * The GDB remote stub, gdbserver, now supports the new file transfer
2800 commands (remote put, remote get, and remote delete).
2802 * The GDB remote stub, gdbserver, now supports run and attach in
2803 extended-remote mode.
2805 * hppa*64*-*-hpux11* target broken
2806 The debugger is unable to start a program and fails with the following
2807 error: "Error trying to get information about dynamic linker".
2808 The gdb-6.7 release is also affected.
2810 * GDB now supports the --enable-targets= configure option to allow
2811 building a single GDB executable that supports multiple remote
2812 target architectures.
2814 * GDB now supports debugging C and C++ programs which use the
2815 Decimal Floating Point extension. In addition, the PowerPC target
2816 now has a set of pseudo-registers to inspect decimal float values
2817 stored in two consecutive float registers.
2819 * The -break-insert MI command can optionally create pending
2822 * Improved support for debugging Ada
2823 Many improvements to the Ada language support have been made. These
2825 - Better support for Ada2005 interface types
2826 - Improved handling of arrays and slices in general
2827 - Better support for Taft-amendment types
2828 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2830 - Improved command completion in Ada
2833 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2838 set print frame-arguments (all|scalars|none)
2839 show print frame-arguments
2840 The value of this variable can be changed to control which argument
2841 values should be printed by the debugger when displaying a frame.
2846 Transfer files to and from a remote target, and delete remote files.
2853 Transfer files to and from a remote target, and delete remote files.
2855 * New remote packets
2862 Open, close, read, write, and delete files on the remote system.
2865 Attach to an existing process on the remote system, in extended-remote
2869 Run a new process on the remote system, in extended-remote mode.
2871 *** Changes in GDB 6.7
2873 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2874 bfd, libiberty and opcodes, as revealed by static analysis donated by
2875 Coverity, Inc. (http://scan.coverity.com).
2877 * When looking up multiply-defined global symbols, GDB will now prefer the
2878 symbol definition in the current shared library if it was built using the
2879 -Bsymbolic linker option.
2881 * When the Text User Interface (TUI) is not configured, GDB will now
2882 recognize the -tui command-line option and print a message that the TUI
2885 * The GDB remote stub, gdbserver, now has lower overhead for high
2886 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2888 * GDB for MIPS targets now autodetects whether a remote target provides
2889 32-bit or 64-bit register values.
2891 * Support for C++ member pointers has been improved.
2893 * GDB now understands XML target descriptions, which specify the
2894 target's overall architecture. GDB can read a description from
2895 a local file or over the remote serial protocol.
2897 * Vectors of single-byte data use a new integer type which is not
2898 automatically displayed as character or string data.
2900 * The /s format now works with the print command. It displays
2901 arrays of single-byte integers and pointers to single-byte integers
2904 * Target descriptions can now describe target-specific registers,
2905 for architectures which have implemented the support (currently
2906 only ARM, M68K, and MIPS).
2908 * GDB and the GDB remote stub, gdbserver, now support the XScale
2911 * The GDB remote stub, gdbserver, has been updated to support
2912 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2913 has been rewritten to use the standard GDB remote protocol.
2915 * GDB can now step into C++ functions which are called through thunks.
2917 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2919 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2920 layout. It also supports a TextSeg= and DataSeg= response when only
2921 segment base addresses (rather than offsets) are available.
2923 * The /i format now outputs any trailing branch delay slot instructions
2924 immediately following the last instruction within the count specified.
2926 * The GDB remote protocol "T" stop reply packet now supports a
2927 "library" response. Combined with the new "qXfer:libraries:read"
2928 packet, this response allows GDB to debug shared libraries on targets
2929 where the operating system manages the list of loaded libraries (e.g.
2930 Windows and SymbianOS).
2932 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2933 (DLLs) on Windows and Windows CE targets.
2935 * GDB now supports a faster verification that a .debug file matches its binary
2936 according to its build-id signature, if the signature is present.
2942 Enable or disable hardware flow control (RTS/CTS) on the serial port
2943 when debugging using remote targets.
2945 set mem inaccessible-by-default
2946 show mem inaccessible-by-default
2947 If the target supplies a memory map, for instance via the remote
2948 protocol's "qXfer:memory-map:read" packet, setting this variable
2949 prevents GDB from accessing memory outside the memory map. This
2950 is useful for targets with memory mapped registers or which react
2951 badly to accesses of unmapped address space.
2953 set breakpoint auto-hw
2954 show breakpoint auto-hw
2955 If the target supplies a memory map, for instance via the remote
2956 protocol's "qXfer:memory-map:read" packet, setting this variable
2957 lets GDB use hardware breakpoints automatically for memory regions
2958 where it can not use software breakpoints. This covers both the
2959 "break" command and internal breakpoints used for other commands
2960 including "next" and "finish".
2963 catch exception unhandled
2964 Stop the program execution when Ada exceptions are raised.
2967 Stop the program execution when an Ada assertion failed.
2971 Set an alternate system root for target files. This is a more
2972 general version of "set solib-absolute-prefix", which is now
2973 an alias to "set sysroot".
2976 Provide extended SPU facility status information. This set of
2977 commands is available only when debugging the Cell/B.E. SPU
2980 * New native configurations
2982 OpenBSD/sh sh*-*openbsd*
2985 unset tdesc filename
2987 Use the specified local file as an XML target description, and do
2988 not query the target for its built-in description.
2992 OpenBSD/sh sh*-*-openbsd*
2993 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2994 Toshiba Media Processor mep-elf
2996 * New remote packets
2999 Ignore the specified signals; pass them directly to the debugged program
3000 without stopping other threads or reporting them to GDB.
3002 qXfer:features:read:
3003 Read an XML target description from the target, which describes its
3008 Read or write contents of an spufs file on the target system. These
3009 packets are available only on the Cell/B.E. SPU architecture.
3011 qXfer:libraries:read:
3012 Report the loaded shared libraries. Combined with new "T" packet
3013 response, this packet allows GDB to debug shared libraries on
3014 targets where the operating system manages the list of loaded
3015 libraries (e.g. Windows and SymbianOS).
3019 Support for these obsolete configurations has been removed.
3027 i[34567]86-*-lynxos*
3028 i[34567]86-*-netware*
3029 i[34567]86-*-sco3.2v5*
3030 i[34567]86-*-sco3.2v4*
3032 i[34567]86-*-sysv4.2*
3035 i[34567]86-*-unixware2*
3036 i[34567]86-*-unixware*
3045 * Other removed features
3052 Various m68k-only ROM monitors.
3059 Various Renesas ROM monitors and debugging interfaces for SH and
3064 Support for a Macraigor serial interface to on-chip debugging.
3065 GDB does not directly support the newer parallel or USB
3070 A debug information format. The predecessor to DWARF 2 and
3071 DWARF 3, which are still supported.
3073 Support for the HP aCC compiler on HP-UX/PA-RISC
3075 SOM-encapsulated symbolic debugging information, automatic
3076 invocation of pxdb, and the aCC custom C++ ABI. This does not
3077 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3078 with aCC can still be debugged on an assembly level.
3080 MIPS ".pdr" sections
3082 A MIPS-specific format used to describe stack frame layout
3083 in debugging information.
3087 GDB could work with an older version of Guile to debug
3088 the interpreter and Scheme programs running in it.
3090 set mips stack-arg-size
3091 set mips saved-gpreg-size
3093 Use "set mips abi" to control parameter passing for MIPS.
3095 *** Changes in GDB 6.6
3100 Cell Broadband Engine SPU spu-elf
3102 * GDB can now be configured as a cross-debugger targeting native Windows
3103 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3104 running on a Windows system over TCP/IP to debug Windows programs.
3106 * The GDB remote stub, gdbserver, has been updated to support Windows and
3107 Cygwin debugging. Both single-threaded and multi-threaded programs are
3110 * The "set trust-readonly-sections" command works again. This command was
3111 broken in GDB 6.3, 6.4, and 6.5.
3113 * The "load" command now supports writing to flash memory, if the remote
3114 stub provides the required support.
3116 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3117 longer requires symbolic debug information (e.g. DWARF-2).
3122 unset substitute-path
3123 show substitute-path
3124 Manage a list of substitution rules that GDB uses to rewrite the name
3125 of the directories where the sources are located. This can be useful
3126 for instance when the sources were moved to a different location
3127 between compilation and debugging.
3131 Print each CLI command as it is executed. Each command is prefixed with
3132 a number of `+' symbols representing the nesting depth.
3133 The source command now has a `-v' option to enable the same feature.
3137 The ARM Demon monitor support (RDP protocol, "target rdp").
3139 Kernel Object Display, an embedded debugging feature which only worked with
3140 an obsolete version of Cisco IOS.
3142 The 'set download-write-size' and 'show download-write-size' commands.
3144 * New remote packets
3147 Tell a stub about GDB client features, and request remote target features.
3148 The first feature implemented is PacketSize, which allows the target to
3149 specify the size of packets it can handle - to minimize the number of
3150 packets required and improve performance when connected to a remote
3154 Fetch an OS auxilliary vector from the remote stub. This packet is a
3155 more efficient replacement for qPart:auxv:read.
3157 qXfer:memory-map:read:
3158 Fetch a memory map from the remote stub, including information about
3159 RAM, ROM, and flash memory devices.
3164 Erase and program a flash memory device.
3166 * Removed remote packets
3169 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3170 used it, and only gdbserver implemented it.
3172 *** Changes in GDB 6.5
3176 Renesas M32C/M16C m32c-elf
3178 Morpho Technologies ms1 ms1-elf
3182 init-if-undefined Initialize a convenience variable, but
3183 only if it doesn't already have a value.
3185 The following commands are presently only implemented for native GNU/Linux:
3187 checkpoint Save a snapshot of the program state.
3189 restart <n> Return the program state to a
3190 previously saved state.
3192 info checkpoints List currently saved checkpoints.
3194 delete-checkpoint <n> Delete a previously saved checkpoint.
3196 set|show detach-on-fork Tell gdb whether to detach from a newly
3197 forked process, or to keep debugging it.
3199 info forks List forks of the user program that
3200 are available to be debugged.
3202 fork <n> Switch to debugging one of several
3203 forks of the user program that are
3204 available to be debugged.
3206 delete-fork <n> Delete a fork from the list of forks
3207 that are available to be debugged (and
3208 kill the forked process).
3210 detach-fork <n> Delete a fork from the list of forks
3211 that are available to be debugged (and
3212 allow the process to continue).
3216 Morpho Technologies ms2 ms1-elf
3218 * Improved Windows host support
3220 GDB now builds as a cross debugger hosted on i686-mingw32, including
3221 native console support, and remote communications using either
3222 network sockets or serial ports.
3224 * Improved Modula-2 language support
3226 GDB can now print most types in the Modula-2 syntax. This includes:
3227 basic types, set types, record types, enumerated types, range types,
3228 pointer types and ARRAY types. Procedure var parameters are correctly
3229 printed and hexadecimal addresses and character constants are also
3230 written in the Modula-2 syntax. Best results can be obtained by using
3231 GNU Modula-2 together with the -gdwarf-2 command line option.
3235 The ARM rdi-share module.
3237 The Netware NLM debug server.
3239 *** Changes in GDB 6.4
3241 * New native configurations
3243 OpenBSD/arm arm*-*-openbsd*
3244 OpenBSD/mips64 mips64-*-openbsd*
3248 Morpho Technologies ms1 ms1-elf
3250 * New command line options
3252 --batch-silent As for --batch, but totally silent.
3253 --return-child-result The debugger will exist with the same value
3254 the child (debugged) program exited with.
3255 --eval-command COMMAND, -ex COMMAND
3256 Execute a single GDB CLI command. This may be
3257 specified multiple times and in conjunction
3258 with the --command (-x) option.
3260 * Deprecated commands removed
3262 The following commands, that were deprecated in 2000, have been
3266 set|show arm disassembly-flavor set|show arm disassembler
3267 othernames set arm disassembler
3268 set|show remotedebug set|show debug remote
3269 set|show archdebug set|show debug arch
3270 set|show eventdebug set|show debug event
3273 * New BSD user-level threads support
3275 It is now possible to debug programs using the user-level threads
3276 library on OpenBSD and FreeBSD. Currently supported (target)
3279 FreeBSD/amd64 x86_64-*-freebsd*
3280 FreeBSD/i386 i386-*-freebsd*
3281 OpenBSD/i386 i386-*-openbsd*
3283 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3284 are not yet supported.
3286 * New support for Matsushita MN10300 w/sim added
3287 (Work in progress). mn10300-elf.
3289 * REMOVED configurations and files
3291 VxWorks and the XDR protocol *-*-vxworks
3292 Motorola MCORE mcore-*-*
3293 National Semiconductor NS32000 ns32k-*-*
3295 * New "set print array-indexes" command
3297 After turning this setting "on", GDB prints the index of each element
3298 when displaying arrays. The default is "off" to preserve the previous
3301 * VAX floating point support
3303 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3305 * User-defined command support
3307 In addition to using $arg0..$arg9 for argument passing, it is now possible
3308 to use $argc to determine now many arguments have been passed. See the
3309 section on user-defined commands in the user manual for more information.
3311 *** Changes in GDB 6.3:
3313 * New command line option
3315 GDB now accepts -l followed by a number to set the timeout for remote
3318 * GDB works with GCC -feliminate-dwarf2-dups
3320 GDB now supports a more compact representation of DWARF-2 debug
3321 information using DW_FORM_ref_addr references. These are produced
3322 by GCC with the option -feliminate-dwarf2-dups and also by some
3323 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3324 to use -feliminate-dwarf2-dups.
3326 * Internationalization
3328 When supported by the host system, GDB will be built with
3329 internationalization (libintl). The task of marking up the sources is
3330 continued, we're looking forward to our first translation.
3334 Initial support for debugging programs compiled with the GNAT
3335 implementation of the Ada programming language has been integrated
3336 into GDB. In this release, support is limited to expression evaluation.
3338 * New native configurations
3340 GNU/Linux/m32r m32r-*-linux-gnu
3344 GDB's remote protocol now includes support for the 'p' packet. This
3345 packet is used to fetch individual registers from a remote inferior.
3347 * END-OF-LIFE registers[] compatibility module
3349 GDB's internal register infrastructure has been completely rewritten.
3350 The new infrastructure making possible the implementation of key new
3351 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3354 GDB 6.3 will be the last release to include the the registers[]
3355 compatibility module that allowed out-of-date configurations to
3356 continue to work. This change directly impacts the following
3366 powerpc bdm protocol
3368 Unless there is activity to revive these configurations, they will be
3369 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3371 * OBSOLETE configurations and files
3373 Configurations that have been declared obsolete in this release have
3374 been commented out. Unless there is activity to revive these
3375 configurations, the next release of GDB will have their sources
3376 permanently REMOVED.
3385 *** Changes in GDB 6.2.1:
3387 * MIPS `break main; run' gave an heuristic-fence-post warning
3389 When attempting to run even a simple program, a warning about
3390 heuristic-fence-post being hit would be reported. This problem has
3393 * MIPS IRIX 'long double' crashed GDB
3395 When examining a long double variable, GDB would get a segmentation
3396 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3397 IRIX long double values).
3401 A bug in the VAX stack code was causing problems with the "next"
3402 command. This problem has been fixed.
3404 *** Changes in GDB 6.2:
3406 * Fix for ``many threads''
3408 On GNU/Linux systems that use the NPTL threads library, a program
3409 rapidly creating and deleting threads would confuse GDB leading to the
3412 ptrace: No such process.
3413 thread_db_get_info: cannot get thread info: generic error
3415 This problem has been fixed.
3417 * "-async" and "-noasync" options removed.
3419 Support for the broken "-noasync" option has been removed (it caused
3422 * New ``start'' command.
3424 This command runs the program until the begining of the main procedure.
3426 * New BSD Kernel Data Access Library (libkvm) interface
3428 Using ``target kvm'' it is now possible to debug kernel core dumps and
3429 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3430 platforms. Currently supported (native-only) configurations are:
3432 FreeBSD/amd64 x86_64-*-freebsd*
3433 FreeBSD/i386 i?86-*-freebsd*
3434 NetBSD/i386 i?86-*-netbsd*
3435 NetBSD/m68k m68*-*-netbsd*
3436 NetBSD/sparc sparc-*-netbsd*
3437 OpenBSD/amd64 x86_64-*-openbsd*
3438 OpenBSD/i386 i?86-*-openbsd*
3439 OpenBSD/m68k m68*-openbsd*
3440 OpenBSD/sparc sparc-*-openbsd*
3442 * Signal trampoline code overhauled
3444 Many generic problems with GDB's signal handling code have been fixed.
3445 These include: backtraces through non-contiguous stacks; recognition
3446 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3447 call; backtrace through a signal trampoline; step into and out of
3448 signal handlers; and single-stepping in the signal trampoline.
3450 Please note that kernel bugs are a limiting factor here. These
3451 features have been shown to work on an s390 GNU/Linux system that
3452 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3454 * Cygwin support for DWARF 2 added.
3456 * New native configurations
3458 GNU/Linux/hppa hppa*-*-linux*
3459 OpenBSD/hppa hppa*-*-openbsd*
3460 OpenBSD/m68k m68*-*-openbsd*
3461 OpenBSD/m88k m88*-*-openbsd*
3462 OpenBSD/powerpc powerpc-*-openbsd*
3463 NetBSD/vax vax-*-netbsd*
3464 OpenBSD/vax vax-*-openbsd*
3466 * END-OF-LIFE frame compatibility module
3468 GDB's internal frame infrastructure has been completely rewritten.
3469 The new infrastructure making it possible to support key new features
3470 including DWARF 2 Call Frame Information. To aid in the task of
3471 migrating old configurations to this new infrastructure, a
3472 compatibility module, that allowed old configurations to continue to
3473 work, was also included.
3475 GDB 6.2 will be the last release to include this frame compatibility
3476 module. This change directly impacts the following configurations:
3486 Unless there is activity to revive these configurations, they will be
3487 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3489 * REMOVED configurations and files
3491 Sun 3, running SunOS 3 m68*-*-sunos3*
3492 Sun 3, running SunOS 4 m68*-*-sunos4*
3493 Sun 2, running SunOS 3 m68000-*-sunos3*
3494 Sun 2, running SunOS 4 m68000-*-sunos4*
3495 Motorola 680x0 running LynxOS m68*-*-lynxos*
3496 AT&T 3b1/Unix pc m68*-att-*
3497 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3498 decstation mips-dec-* mips-little-*
3499 riscos mips-*-riscos* mips-*-sysv*
3500 sonymips mips-sony-*
3501 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3503 *** Changes in GDB 6.1.1:
3505 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3507 The TUI (Text-mode User Interface) is now built as part of a default
3508 GDB configuration. It is enabled by either selecting the TUI with the
3509 command line option "-i=tui" or by running the separate "gdbtui"
3510 program. For more information on the TUI, see the manual "Debugging
3513 * Pending breakpoint support (also included in GDB 6.1)
3515 Support has been added to allow you to specify breakpoints in shared
3516 libraries that have not yet been loaded. If a breakpoint location
3517 cannot be found, and the "breakpoint pending" option is set to auto,
3518 GDB queries you if you wish to make the breakpoint pending on a future
3519 shared-library load. If and when GDB resolves the breakpoint symbol,
3520 the pending breakpoint is removed as one or more regular breakpoints
3523 Pending breakpoints are very useful for GCJ Java debugging.
3525 * Fixed ISO-C build problems
3527 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3528 non ISO-C code that stopped them being built using a more strict ISO-C
3529 compiler (e.g., IBM's C compiler).
3531 * Fixed build problem on IRIX 5
3533 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3534 wasn't able to compile compile on an IRIX 5 system.
3536 * Added execute permission to gdb/gdbserver/configure
3538 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3539 permission. This bug would cause configure to fail on a number of
3540 systems (Solaris, IRIX). Ref: server/519.
3542 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3544 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3545 has been updated to use constant array sizes.
3547 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3549 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3550 its generated DWARF Call Frame Info. This encoding was causing GDB to
3551 panic, that panic has been fixed. Ref: gdb/1628.
3553 * Fixed a problem when examining parameters in shared library code.
3555 When examining parameters in optimized shared library code generated
3556 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3557 not available''. GDB now correctly displays the variable's value.
3559 *** Changes in GDB 6.1:
3561 * Removed --with-mmalloc
3563 Support for the mmalloc memory manager has been removed, as it
3564 conflicted with the internal gdb byte cache.
3566 * Changes in AMD64 configurations
3568 The AMD64 target now includes the %cs and %ss registers. As a result
3569 the AMD64 remote protocol has changed; this affects the floating-point
3570 and SSE registers. If you rely on those registers for your debugging,
3571 you should upgrade gdbserver on the remote side.
3573 * Revised SPARC target
3575 The SPARC target has been completely revised, incorporating the
3576 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3577 support for LynxOS and SunOS 4 has been dropped. Calling functions
3578 from within GDB on operating systems with a non-executable stack
3579 (Solaris, OpenBSD) now works.
3583 GDB has a new C++ demangler which does a better job on the mangled
3584 names generated by current versions of g++. It also runs faster, so
3585 with this and other changes gdb should now start faster on large C++
3588 * DWARF 2 Location Expressions
3590 GDB support for location expressions has been extended to support function
3591 arguments and frame bases. Older versions of GDB could crash when they
3594 * C++ nested types and namespaces
3596 GDB's support for nested types and namespaces in C++ has been
3597 improved, especially if you use the DWARF 2 debugging format. (This
3598 is the default for recent versions of GCC on most platforms.)
3599 Specifically, if you have a class "Inner" defined within a class or
3600 namespace "Outer", then GDB realizes that the class's name is
3601 "Outer::Inner", not simply "Inner". This should greatly reduce the
3602 frequency of complaints about not finding RTTI symbols. In addition,
3603 if you are stopped at inside of a function defined within a namespace,
3604 GDB modifies its name lookup accordingly.
3606 * New native configurations
3608 NetBSD/amd64 x86_64-*-netbsd*
3609 OpenBSD/amd64 x86_64-*-openbsd*
3610 OpenBSD/alpha alpha*-*-openbsd*
3611 OpenBSD/sparc sparc-*-openbsd*
3612 OpenBSD/sparc64 sparc64-*-openbsd*
3614 * New debugging protocols
3616 M32R with SDI protocol m32r-*-elf*
3618 * "set prompt-escape-char" command deleted.
3620 The command "set prompt-escape-char" has been deleted. This command,
3621 and its very obscure effet on GDB's prompt, was never documented,
3622 tested, nor mentioned in the NEWS file.
3624 * OBSOLETE configurations and files
3626 Configurations that have been declared obsolete in this release have
3627 been commented out. Unless there is activity to revive these
3628 configurations, the next release of GDB will have their sources
3629 permanently REMOVED.
3631 Sun 3, running SunOS 3 m68*-*-sunos3*
3632 Sun 3, running SunOS 4 m68*-*-sunos4*
3633 Sun 2, running SunOS 3 m68000-*-sunos3*
3634 Sun 2, running SunOS 4 m68000-*-sunos4*
3635 Motorola 680x0 running LynxOS m68*-*-lynxos*
3636 AT&T 3b1/Unix pc m68*-att-*
3637 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3638 decstation mips-dec-* mips-little-*
3639 riscos mips-*-riscos* mips-*-sysv*
3640 sonymips mips-sony-*
3641 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3643 * REMOVED configurations and files
3645 SGI Irix-4.x mips-sgi-irix4 or iris4
3646 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3647 Z8000 simulator z8k-zilog-none or z8ksim
3648 Matsushita MN10200 w/simulator mn10200-*-*
3649 H8/500 simulator h8500-hitachi-hms or h8500hms
3650 HP/PA running BSD hppa*-*-bsd*
3651 HP/PA running OSF/1 hppa*-*-osf*
3652 HP/PA Pro target hppa*-*-pro*
3653 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3654 386BSD i[3456]86-*-bsd*
3655 Sequent family i[3456]86-sequent-sysv4*
3656 i[3456]86-sequent-sysv*
3657 i[3456]86-sequent-bsd*
3658 SPARC running LynxOS sparc-*-lynxos*
3659 SPARC running SunOS 4 sparc-*-sunos4*
3660 Tsqware Sparclet sparclet-*-*
3661 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3663 *** Changes in GDB 6.0:
3667 Support for debugging the Objective-C programming language has been
3668 integrated into GDB.
3670 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3672 DWARF 2's Call Frame Information makes available compiler generated
3673 information that more exactly describes the program's run-time stack.
3674 By using this information, GDB is able to provide more robust stack
3677 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3678 have been updated to use a new backtrace mechanism which includes
3679 DWARF 2 CFI support.
3683 GDB's remote protocol has been extended to include support for hosted
3684 file I/O (where the remote target uses GDB's file system). See GDB's
3685 remote protocol documentation for details.
3687 * All targets using the new architecture framework.
3689 All of GDB's targets have been updated to use the new internal
3690 architecture framework. The way is now open for future GDB releases
3691 to include cross-architecture native debugging support (i386 on amd64,
3694 * GNU/Linux's Thread Local Storage (TLS)
3696 GDB now includes support for for the GNU/Linux implementation of
3697 per-thread variables.
3699 * GNU/Linux's Native POSIX Thread Library (NPTL)
3701 GDB's thread code has been updated to work with either the new
3702 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3704 * Separate debug info.
3706 GDB, in conjunction with BINUTILS, now supports a mechanism for
3707 automatically loading debug information from a separate file. Instead
3708 of shipping full debug and non-debug versions of system libraries,
3709 system integrators can now instead ship just the stripped libraries
3710 and optional debug files.
3712 * DWARF 2 Location Expressions
3714 DWARF 2 Location Expressions allow the compiler to more completely
3715 describe the location of variables (even in optimized code) to the
3718 GDB now includes preliminary support for location expressions (support
3719 for DW_OP_piece is still missing).
3723 A number of long standing bugs that caused GDB to die while starting a
3724 Java application have been fixed. GDB's Java support is now
3725 considered "useable".
3727 * GNU/Linux support for fork, vfork, and exec.
3729 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3730 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3733 * GDB supports logging output to a file
3735 There are two new commands, "set logging" and "show logging", which can be
3736 used to capture GDB's output to a file.
3738 * The meaning of "detach" has changed for gdbserver
3740 The "detach" command will now resume the application, as documented. To
3741 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3744 * d10v, m68hc11 `regs' command deprecated
3746 The `info registers' command has been updated so that it displays the
3747 registers using a format identical to the old `regs' command.
3751 A new command, "maint set profile on/off", has been added. This command can
3752 be used to enable or disable profiling while running GDB, to profile a
3753 session or a set of commands. In addition there is a new configure switch,
3754 "--enable-profiling", which will cause GDB to be compiled with profiling
3755 data, for more informative profiling results.
3757 * Default MI syntax changed to "mi2".
3759 The default MI (machine interface) syntax, enabled by the command line
3760 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3761 "mi1", can be enabled by specifying the option "-i=mi1".
3763 Support for the original "mi0" syntax (included in GDB 5.0) has been
3766 Fix for gdb/192: removed extraneous space when displaying frame level.
3767 Fix for gdb/672: update changelist is now output in mi list format.
3768 Fix for gdb/702: a -var-assign that updates the value now shows up
3769 in a subsequent -var-update.
3771 * New native configurations.
3773 FreeBSD/amd64 x86_64-*-freebsd*
3775 * Multi-arched targets.
3777 HP/PA HPUX11 hppa*-*-hpux*
3778 Renesas M32R/D w/simulator m32r-*-elf*
3780 * OBSOLETE configurations and files
3782 Configurations that have been declared obsolete in this release have
3783 been commented out. Unless there is activity to revive these
3784 configurations, the next release of GDB will have their sources
3785 permanently REMOVED.
3787 Z8000 simulator z8k-zilog-none or z8ksim
3788 Matsushita MN10200 w/simulator mn10200-*-*
3789 H8/500 simulator h8500-hitachi-hms or h8500hms
3790 HP/PA running BSD hppa*-*-bsd*
3791 HP/PA running OSF/1 hppa*-*-osf*
3792 HP/PA Pro target hppa*-*-pro*
3793 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3794 Sequent family i[3456]86-sequent-sysv4*
3795 i[3456]86-sequent-sysv*
3796 i[3456]86-sequent-bsd*
3797 Tsqware Sparclet sparclet-*-*
3798 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3800 * REMOVED configurations and files
3803 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3804 IBM AIX PS/2 i[3456]86-*-aix
3805 i386 running Mach 3.0 i[3456]86-*-mach3*
3806 i386 running Mach i[3456]86-*-mach*
3807 i386 running OSF/1 i[3456]86-*osf1mk*
3808 HP/Apollo 68k Family m68*-apollo*-sysv*,
3810 m68*-hp-bsd*, m68*-hp-hpux*
3811 Argonaut Risc Chip (ARC) arc-*-*
3812 Mitsubishi D30V d30v-*-*
3813 Fujitsu FR30 fr30-*-elf*
3814 OS/9000 i[34]86-*-os9k
3815 I960 with MON960 i960-*-coff
3817 * MIPS $fp behavior changed
3819 The convenience variable $fp, for the MIPS, now consistently returns
3820 the address of the current frame's base. Previously, depending on the
3821 context, $fp could refer to either $sp or the current frame's base
3822 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3823 The GNU Source-Level Debugger''.
3825 *** Changes in GDB 5.3:
3827 * GNU/Linux shared library multi-threaded performance improved.
3829 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3830 `/proc', in preference to `ptrace' for memory reads. This may result
3831 in an improvement in the start-up time of multi-threaded, shared
3832 library applications when run under GDB. One GDB user writes: ``loads
3833 shared libs like mad''.
3835 * ``gdbserver'' now supports multi-threaded applications on some targets
3837 Support for debugging multi-threaded applications which use
3838 the GNU/Linux LinuxThreads package has been added for
3839 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3840 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3842 * GDB now supports C/C++ preprocessor macros.
3844 GDB now expands preprocessor macro invocations in C/C++ expressions,
3845 and provides various commands for showing macro definitions and how
3848 The new command `macro expand EXPRESSION' expands any macro
3849 invocations in expression, and shows the result.
3851 The new command `show macro MACRO-NAME' shows the definition of the
3852 macro named MACRO-NAME, and where it was defined.
3854 Most compilers don't include information about macros in the debugging
3855 information by default. In GCC 3.1, for example, you need to compile
3856 your program with the options `-gdwarf-2 -g3'. If the macro
3857 information is present in the executable, GDB will read it.
3859 * Multi-arched targets.
3861 DEC Alpha (partial) alpha*-*-*
3862 DEC VAX (partial) vax-*-*
3864 National Semiconductor NS32000 (partial) ns32k-*-*
3865 Motorola 68000 (partial) m68k-*-*
3866 Motorola MCORE mcore-*-*
3870 Fujitsu FRV architecture added by Red Hat frv*-*-*
3873 * New native configurations
3875 Alpha NetBSD alpha*-*-netbsd*
3876 SH NetBSD sh*-*-netbsdelf*
3877 MIPS NetBSD mips*-*-netbsd*
3878 UltraSPARC NetBSD sparc64-*-netbsd*
3880 * OBSOLETE configurations and files
3882 Configurations that have been declared obsolete in this release have
3883 been commented out. Unless there is activity to revive these
3884 configurations, the next release of GDB will have their sources
3885 permanently REMOVED.
3887 Mitsubishi D30V d30v-*-*
3888 OS/9000 i[34]86-*-os9k
3889 IBM AIX PS/2 i[3456]86-*-aix
3890 Fujitsu FR30 fr30-*-elf*
3891 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3892 Argonaut Risc Chip (ARC) arc-*-*
3893 i386 running Mach 3.0 i[3456]86-*-mach3*
3894 i386 running Mach i[3456]86-*-mach*
3895 i386 running OSF/1 i[3456]86-*osf1mk*
3896 HP/Apollo 68k Family m68*-apollo*-sysv*,
3898 m68*-hp-bsd*, m68*-hp-hpux*
3899 I960 with MON960 i960-*-coff
3901 * OBSOLETE languages
3903 CHILL, a Pascal like language used by telecommunications companies.
3905 * REMOVED configurations and files
3907 AMD 29k family via UDI a29k-amd-udi, udi29k
3908 A29K VxWorks a29k-*-vxworks
3909 AMD 29000 embedded, using EBMON a29k-none-none
3910 AMD 29000 embedded with COFF a29k-none-coff
3911 AMD 29000 embedded with a.out a29k-none-aout
3913 testsuite/gdb.hp/gdb.threads-hp/ directory
3915 * New command "set max-user-call-depth <nnn>"
3917 This command allows the user to limit the call depth of user-defined
3918 commands. The default is 1024.
3920 * Changes in FreeBSD/i386 native debugging.
3922 Support for the "generate-core-file" has been added.
3924 * New commands "dump", "append", and "restore".
3926 These commands allow data to be copied from target memory
3927 to a bfd-format or binary file (dump and append), and back
3928 from a file into memory (restore).
3930 * Improved "next/step" support on multi-processor Alpha Tru64.
3932 The previous single-step mechanism could cause unpredictable problems,
3933 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3934 of a software single-step mechanism prevents this.
3936 *** Changes in GDB 5.2.1:
3944 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3945 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3946 Fix, by Joel Brobecker imported from mainline.
3948 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3949 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3950 Fix, by Fred Fish, imported from mainline.
3952 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3953 Surprisingly enough, it works now.
3954 By Michal Ludvig, imported from mainline.
3956 i386 hardware watchpoint support:
3957 avoid misses on second run for some targets.
3958 By Pierre Muller, imported from mainline.
3960 *** Changes in GDB 5.2:
3962 * New command "set trust-readonly-sections on[off]".
3964 This command is a hint that tells gdb that read-only sections
3965 really are read-only (ie. that their contents will not change).
3966 In this mode, gdb will go to the object file rather than the
3967 target to read memory from read-only sections (such as ".text").
3968 This can be a significant performance improvement on some
3969 (notably embedded) targets.
3971 * New command "generate-core-file" (or "gcore").
3973 This new gdb command allows the user to drop a core file of the child
3974 process state at any time. So far it's been implemented only for
3975 GNU/Linux and Solaris, but should be relatively easily ported to other
3976 hosts. Argument is core file name (defaults to core.<pid>).
3978 * New command line option
3980 GDB now accepts --pid or -p followed by a process id.
3982 * Change in command line behavior -- corefiles vs. process ids.
3984 There is a subtle behavior in the way in which GDB handles
3985 command line arguments. The first non-flag argument is always
3986 a program to debug, but the second non-flag argument may either
3987 be a corefile or a process id. Previously, GDB would attempt to
3988 open the second argument as a corefile, and if that failed, would
3989 issue a superfluous error message and then attempt to attach it as
3990 a process. Now, if the second argument begins with a non-digit,
3991 it will be treated as a corefile. If it begins with a digit,
3992 GDB will attempt to attach it as a process, and if no such process
3993 is found, will then attempt to open it as a corefile.
3995 * Changes in ARM configurations.
3997 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3998 configuration is fully multi-arch.
4000 * New native configurations
4002 ARM NetBSD arm*-*-netbsd*
4003 x86 OpenBSD i[3456]86-*-openbsd*
4004 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4005 Sparc64 running FreeBSD sparc64-*-freebsd*
4009 Sanyo XStormy16 xstormy16-elf
4011 * OBSOLETE configurations and files
4013 Configurations that have been declared obsolete in this release have
4014 been commented out. Unless there is activity to revive these
4015 configurations, the next release of GDB will have their sources
4016 permanently REMOVED.
4018 AMD 29k family via UDI a29k-amd-udi, udi29k
4019 A29K VxWorks a29k-*-vxworks
4020 AMD 29000 embedded, using EBMON a29k-none-none
4021 AMD 29000 embedded with COFF a29k-none-coff
4022 AMD 29000 embedded with a.out a29k-none-aout
4024 testsuite/gdb.hp/gdb.threads-hp/ directory
4026 * REMOVED configurations and files
4028 TI TMS320C80 tic80-*-*
4030 PowerPC Solaris powerpcle-*-solaris*
4031 PowerPC Windows NT powerpcle-*-cygwin32
4032 PowerPC Netware powerpc-*-netware*
4033 Harris/CXUX m88k m88*-harris-cxux*
4034 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4035 ns32k-utek-sysv* ns32k-utek-*
4036 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4037 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4038 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4039 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4040 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4042 * Changes to command line processing
4044 The new `--args' feature can be used to specify command-line arguments
4045 for the inferior from gdb's command line.
4047 * Changes to key bindings
4049 There is a new `operate-and-get-next' function bound to `C-o'.
4051 *** Changes in GDB 5.1.1
4053 Fix compile problem on DJGPP.
4055 Fix a problem with floating-point registers on the i386 being
4058 Fix to stop GDB crashing on .debug_str debug info.
4060 Numerous documentation fixes.
4062 Numerous testsuite fixes.
4064 *** Changes in GDB 5.1:
4066 * New native configurations
4068 Alpha FreeBSD alpha*-*-freebsd*
4069 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4070 MIPS GNU/Linux mips*-*-linux*
4071 MIPS SGI Irix 6.x mips*-sgi-irix6*
4072 ia64 AIX ia64-*-aix*
4073 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4077 Motorola 68HC11 and 68HC12 m68hc11-elf
4079 UltraSparc running GNU/Linux sparc64-*-linux*
4081 * OBSOLETE configurations and files
4083 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4084 Harris/CXUX m88k m88*-harris-cxux*
4085 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4086 ns32k-utek-sysv* ns32k-utek-*
4087 TI TMS320C80 tic80-*-*
4089 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4090 PowerPC Solaris powerpcle-*-solaris*
4091 PowerPC Windows NT powerpcle-*-cygwin32
4092 PowerPC Netware powerpc-*-netware*
4093 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4094 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4095 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4096 Apple Macintosh (MPW) host N/A
4098 stuff.c (Program to stuff files into a specially prepared space in kdb)
4099 kdb-start.c (Main loop for the standalone kernel debugger)
4101 Configurations that have been declared obsolete in this release have
4102 been commented out. Unless there is activity to revive these
4103 configurations, the next release of GDB will have their sources
4104 permanently REMOVED.
4106 * REMOVED configurations and files
4108 Altos 3068 m68*-altos-*
4109 Convex c1-*-*, c2-*-*
4111 ARM RISCix arm-*-* (as host)
4115 * GDB has been converted to ISO C.
4117 GDB's source code has been converted to ISO C. In particular, the
4118 sources are fully protoized, and rely on standard headers being
4123 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4125 * The MI enabled by default.
4127 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4128 revised and enabled by default. Packages which use GDB as a debugging
4129 engine behind a UI or another front end are encouraged to switch to
4130 using the GDB/MI interface, instead of the old annotations interface
4131 which is now deprecated.
4133 * Support for debugging Pascal programs.
4135 GDB now includes support for debugging Pascal programs. The following
4136 main features are supported:
4138 - Pascal-specific data types such as sets;
4140 - automatic recognition of Pascal sources based on file-name
4143 - Pascal-style display of data types, variables, and functions;
4145 - a Pascal expression parser.
4147 However, some important features are not yet supported.
4149 - Pascal string operations are not supported at all;
4151 - there are some problems with boolean types;
4153 - Pascal type hexadecimal constants are not supported
4154 because they conflict with the internal variables format;
4156 - support for Pascal objects and classes is not full yet;
4158 - unlike Pascal, GDB is case-sensitive for symbol names.
4160 * Changes in completion.
4162 Commands such as `shell', `run' and `set args', which pass arguments
4163 to inferior programs, now complete on file names, similar to what
4164 users expect at the shell prompt.
4166 Commands which accept locations, such as `disassemble', `print',
4167 `breakpoint', `until', etc. now complete on filenames as well as
4168 program symbols. Thus, if you type "break foob TAB", and the source
4169 files linked into the programs include `foobar.c', that file name will
4170 be one of the candidates for completion. However, file names are not
4171 considered for completion after you typed a colon that delimits a file
4172 name from a name of a function in that file, as in "break foo.c:bar".
4174 `set demangle-style' completes on available demangling styles.
4176 * New platform-independent commands:
4178 It is now possible to define a post-hook for a command as well as a
4179 hook that runs before the command. For more details, see the
4180 documentation of `hookpost' in the GDB manual.
4182 * Changes in GNU/Linux native debugging.
4184 Support for debugging multi-threaded programs has been completely
4185 revised for all platforms except m68k and sparc. You can now debug as
4186 many threads as your system allows you to have.
4188 Attach/detach is supported for multi-threaded programs.
4190 Support for SSE registers was added for x86. This doesn't work for
4191 multi-threaded programs though.
4193 * Changes in MIPS configurations.
4195 Multi-arch support is enabled for all MIPS configurations.
4197 GDB can now be built as native debugger on SGI Irix 6.x systems for
4198 debugging n32 executables. (Debugging 64-bit executables is not yet
4201 * Unified support for hardware watchpoints in all x86 configurations.
4203 Most (if not all) native x86 configurations support hardware-assisted
4204 breakpoints and watchpoints in a unified manner. This support
4205 implements debug register sharing between watchpoints, which allows to
4206 put a virtually infinite number of watchpoints on the same address,
4207 and also supports watching regions up to 16 bytes with several debug
4210 The new maintenance command `maintenance show-debug-regs' toggles
4211 debugging print-outs in functions that insert, remove, and test
4212 watchpoints and hardware breakpoints.
4214 * Changes in the DJGPP native configuration.
4216 New command ``info dos sysinfo'' displays assorted information about
4217 the CPU, OS, memory, and DPMI server.
4219 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4220 display information about segment descriptors stored in GDT, LDT, and
4223 New commands ``info dos pde'' and ``info dos pte'' display entries
4224 from Page Directory and Page Tables (for now works with CWSDPMI only).
4225 New command ``info dos address-pte'' displays the Page Table entry for
4226 a given linear address.
4228 GDB can now pass command lines longer than 126 characters to the
4229 program being debugged (requires an update to the libdbg.a library
4230 which is part of the DJGPP development kit).
4232 DWARF2 debug info is now supported.
4234 It is now possible to `step' and `next' through calls to `longjmp'.
4236 * Changes in documentation.
4238 All GDB documentation was converted to GFDL, the GNU Free
4239 Documentation License.
4241 Tracepoints-related commands are now fully documented in the GDB
4244 TUI, the Text-mode User Interface, is now documented in the manual.
4246 Tracepoints-related commands are now fully documented in the GDB
4249 The "GDB Internals" manual now has an index. It also includes
4250 documentation of `ui_out' functions, GDB coding standards, x86
4251 hardware watchpoints, and memory region attributes.
4253 * GDB's version number moved to ``version.in''
4255 The Makefile variable VERSION has been replaced by the file
4256 ``version.in''. People creating GDB distributions should update the
4257 contents of this file.
4261 GUD support is now a standard part of the EMACS distribution.
4263 *** Changes in GDB 5.0:
4265 * Improved support for debugging FP programs on x86 targets
4267 Unified and much-improved support for debugging floating-point
4268 programs on all x86 targets. In particular, ``info float'' now
4269 displays the FP registers in the same format on all x86 targets, with
4270 greater level of detail.
4272 * Improvements and bugfixes in hardware-assisted watchpoints
4274 It is now possible to watch array elements, struct members, and
4275 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4276 on x86 targets no longer erroneously trigger when the address is
4279 * Improvements in the native DJGPP version of GDB
4281 The distribution now includes all the scripts and auxiliary files
4282 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4283 machines ``out of the box''.
4285 The DJGPP version can now debug programs that use signals. It is
4286 possible to catch signals that happened in the debuggee, deliver
4287 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4288 would kill the program being debugged.) Programs that hook hardware
4289 interrupts (keyboard, timer, etc.) can also be debugged.
4291 It is now possible to debug DJGPP programs that redirect their
4292 standard handles or switch them to raw (as opposed to cooked) mode, or
4293 even close them. The command ``run < foo > bar'' works as expected,
4294 and ``info terminal'' reports useful information about the debuggee's
4295 terminal, including raw/cooked mode, redirection, etc.
4297 The DJGPP version now uses termios functions for console I/O, which
4298 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4301 DOS-style file names with drive letters are now fully supported by
4304 It is now possible to debug DJGPP programs that switch their working
4305 directory. It is also possible to rerun the debuggee any number of
4306 times without restarting GDB; thus, you can use the same setup,
4307 breakpoints, etc. for many debugging sessions.
4309 * New native configurations
4311 ARM GNU/Linux arm*-*-linux*
4312 PowerPC GNU/Linux powerpc-*-linux*
4316 Motorola MCore mcore-*-*
4317 x86 VxWorks i[3456]86-*-vxworks*
4318 PowerPC VxWorks powerpc-*-vxworks*
4319 TI TMS320C80 tic80-*-*
4321 * OBSOLETE configurations
4323 Altos 3068 m68*-altos-*
4324 Convex c1-*-*, c2-*-*
4326 ARM RISCix arm-*-* (as host)
4329 Configurations that have been declared obsolete will be commented out,
4330 but the code will be left in place. If there is no activity to revive
4331 these configurations before the next release of GDB, the sources will
4332 be permanently REMOVED.
4334 * Gould support removed
4336 Support for the Gould PowerNode and NP1 has been removed.
4338 * New features for SVR4
4340 On SVR4 native platforms (such as Solaris), if you attach to a process
4341 without first loading a symbol file, GDB will now attempt to locate and
4342 load symbols from the running process's executable file.
4344 * Many C++ enhancements
4346 C++ support has been greatly improved. Overload resolution now works properly
4347 in almost all cases. RTTI support is on the way.
4349 * Remote targets can connect to a sub-program
4351 A popen(3) style serial-device has been added. This device starts a
4352 sub-process (such as a stand-alone simulator) and then communicates
4353 with that. The sub-program to run is specified using the syntax
4354 ``|<program> <args>'' vis:
4356 (gdb) set remotedebug 1
4357 (gdb) target extended-remote |mn10300-elf-sim program-args
4359 * MIPS 64 remote protocol
4361 A long standing bug in the mips64 remote protocol where by GDB
4362 expected certain 32 bit registers (ex SR) to be transfered as 32
4363 instead of 64 bits has been fixed.
4365 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4366 added to provide backward compatibility with older versions of GDB.
4368 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4370 The command ``set remotebinarydownload'' command has been replaced by
4371 ``set remote X-packet''. Other commands in ``set remote'' family
4372 include ``set remote P-packet''.
4374 * Breakpoint commands accept ranges.
4376 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4377 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4378 ``tracepoint passcount'' also accepts a range of tracepoints.
4380 * ``apropos'' command added.
4382 The ``apropos'' command searches through command names and
4383 documentation strings, printing out matches, making it much easier to
4384 try to find a command that does what you are looking for.
4388 A new machine oriented interface (MI) has been added to GDB. This
4389 interface is designed for debug environments running GDB as a separate
4390 process. This is part of the long term libGDB project. See the
4391 "GDB/MI" chapter of the GDB manual for further information. It can be
4392 enabled by configuring with:
4394 .../configure --enable-gdbmi
4396 *** Changes in GDB-4.18:
4398 * New native configurations
4400 HP-UX 10.20 hppa*-*-hpux10.20
4401 HP-UX 11.x hppa*-*-hpux11.0*
4402 M68K GNU/Linux m68*-*-linux*
4406 Fujitsu FR30 fr30-*-elf*
4407 Intel StrongARM strongarm-*-*
4408 Mitsubishi D30V d30v-*-*
4410 * OBSOLETE configurations
4412 Gould PowerNode, NP1 np1-*-*, pn-*-*
4414 Configurations that have been declared obsolete will be commented out,
4415 but the code will be left in place. If there is no activity to revive
4416 these configurations before the next release of GDB, the sources will
4417 be permanently REMOVED.
4421 As a compatibility experiment, GDB's source files buildsym.h and
4422 buildsym.c have been converted to pure standard C, no longer
4423 containing any K&R compatibility code. We believe that all systems in
4424 use today either come with a standard C compiler, or have a GCC port
4425 available. If this is not true, please report the affected
4426 configuration to bug-gdb@gnu.org immediately. See the README file for
4427 information about getting a standard C compiler if you don't have one
4432 GDB now uses readline 2.2.
4434 * set extension-language
4436 You can now control the mapping between filename extensions and source
4437 languages by using the `set extension-language' command. For instance,
4438 you can ask GDB to treat .c files as C++ by saying
4439 set extension-language .c c++
4440 The command `info extensions' lists all of the recognized extensions
4441 and their associated languages.
4443 * Setting processor type for PowerPC and RS/6000
4445 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4446 you can use the `set processor' command to specify what variant of the
4447 PowerPC family you are debugging. The command
4451 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4452 following PowerPC and RS6000 variants:
4454 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4455 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4457 403GC IBM PowerPC 403GC
4458 505 Motorola PowerPC 505
4459 860 Motorola PowerPC 860 or 850
4460 601 Motorola PowerPC 601
4461 602 Motorola PowerPC 602
4462 603 Motorola/IBM PowerPC 603 or 603e
4463 604 Motorola PowerPC 604 or 604e
4464 750 Motorola/IBM PowerPC 750 or 750
4466 At the moment, this command just tells GDB what to name the
4467 special-purpose processor registers. Since almost all the affected
4468 registers are inaccessible to user-level programs, this command is
4469 only useful for remote debugging in its present form.
4473 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4474 more extensive support for HP-UX. Added features include shared
4475 library support, kernel threads and hardware watchpoints for 11.00,
4476 support for HP's ANSI C and C++ compilers, and a compatibility mode
4477 for xdb and dbx commands.
4481 HP's donation includes the new concept of catchpoints, which is a
4482 generalization of the old catch command. On HP-UX, it is now possible
4483 to catch exec, fork, and vfork, as well as library loading.
4485 This means that the existing catch command has changed; its first
4486 argument now specifies the type of catch to be set up. See the
4487 output of "help catch" for a list of catchpoint types.
4489 * Debugging across forks
4491 On HP-UX, you can choose which process to debug when a fork() happens
4496 HP has donated a curses-based terminal user interface (TUI). To get
4497 it, build with --enable-tui. Although this can be enabled for any
4498 configuration, at present it only works for native HP debugging.
4500 * GDB remote protocol additions
4502 A new protocol packet 'X' that writes binary data is now available.
4503 Default behavior is to try 'X', then drop back to 'M' if the stub
4504 fails to respond. The settable variable `remotebinarydownload'
4505 allows explicit control over the use of 'X'.
4507 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4508 full 64-bit address. The command
4510 set remoteaddresssize 32
4512 can be used to revert to the old behaviour. For existing remote stubs
4513 the change should not be noticed, as the additional address information
4516 In order to assist in debugging stubs, you may use the maintenance
4517 command `packet' to send any text string to the stub. For instance,
4519 maint packet heythere
4521 sends the packet "$heythere#<checksum>". Note that it is very easy to
4522 disrupt a debugging session by sending the wrong packet at the wrong
4525 The compare-sections command allows you to compare section data on the
4526 target to what is in the executable file without uploading or
4527 downloading, by comparing CRC checksums.
4529 * Tracing can collect general expressions
4531 You may now collect general expressions at tracepoints. This requires
4532 further additions to the target-side stub; see tracepoint.c and
4533 doc/agentexpr.texi for further details.
4535 * mask-address variable for Mips
4537 For Mips targets, you may control the zeroing of the upper 32 bits of
4538 a 64-bit address by entering `set mask-address on'. This is mainly
4539 of interest to users of embedded R4xxx and R5xxx processors.
4541 * Higher serial baud rates
4543 GDB's serial code now allows you to specify baud rates 57600, 115200,
4544 230400, and 460800 baud. (Note that your host system may not be able
4545 to achieve all of these rates.)
4549 The i960 configuration now includes an initial implementation of a
4550 builtin simulator, contributed by Jim Wilson.
4553 *** Changes in GDB-4.17:
4555 * New native configurations
4557 Alpha GNU/Linux alpha*-*-linux*
4558 Unixware 2.x i[3456]86-unixware2*
4559 Irix 6.x mips*-sgi-irix6*
4560 PowerPC GNU/Linux powerpc-*-linux*
4561 PowerPC Solaris powerpcle-*-solaris*
4562 Sparc GNU/Linux sparc-*-linux*
4563 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4567 Argonaut Risc Chip (ARC) arc-*-*
4568 Hitachi H8/300S h8300*-*-*
4569 Matsushita MN10200 w/simulator mn10200-*-*
4570 Matsushita MN10300 w/simulator mn10300-*-*
4571 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4572 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4573 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4574 Mitsubishi D10V w/simulator d10v-*-*
4575 Mitsubishi M32R/D w/simulator m32r-*-elf*
4576 Tsqware Sparclet sparclet-*-*
4577 NEC V850 w/simulator v850-*-*
4579 * New debugging protocols
4581 ARM with RDI protocol arm*-*-*
4582 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4583 DDB and LSI variants of PMON protocol mips*-*-*
4584 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4585 PowerPC with SDS protocol powerpc{,le}-*-eabi
4586 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4590 All configurations can now understand and use the DWARF 2 debugging
4591 format. The choice is automatic, if the symbol file contains DWARF 2
4596 GDB now includes basic Java language support. This support is
4597 only useful with Java compilers that produce native machine code.
4599 * solib-absolute-prefix and solib-search-path
4601 For SunOS and SVR4 shared libraries, you may now set the prefix for
4602 loading absolute shared library symbol files, and the search path for
4603 locating non-absolute shared library symbol files.
4605 * Live range splitting
4607 GDB can now effectively debug code for which GCC has performed live
4608 range splitting as part of its optimization. See gdb/doc/LRS for
4609 more details on the expected format of the stabs information.
4613 GDB's support for the GNU Hurd, including thread debugging, has been
4614 updated to work with current versions of the Hurd.
4618 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4619 instruction set. ARM GDB automatically detects when Thumb
4620 instructions are in use, and adjusts disassembly and backtracing
4625 GDB's MIPS target configurations now handle the MIP16 16-bit
4630 GDB now includes support for overlays; if an executable has been
4631 linked such that multiple sections are based at the same address, GDB
4632 will decide which section to use for symbolic info. You can choose to
4633 control the decision manually, using overlay commands, or implement
4634 additional target-side support and use "overlay load-target" to bring
4635 in the overlay mapping. Do "help overlay" for more detail.
4639 The command "info symbol <address>" displays information about
4640 the symbol at the specified address.
4644 The standard remote protocol now includes an extension that allows
4645 asynchronous collection and display of trace data. This requires
4646 extensive support in the target-side debugging stub. Tracing mode
4647 includes a new interaction mode in GDB and new commands: see the
4648 file tracepoint.c for more details.
4652 Configurations for embedded MIPS now include a simulator contributed
4653 by Cygnus Solutions. The simulator supports the instruction sets
4654 of most MIPS variants.
4658 Sparc configurations may now include the ERC32 simulator contributed
4659 by the European Space Agency. The simulator is not built into
4660 Sparc targets by default; configure with --enable-sim to include it.
4664 For target configurations that may include multiple variants of a
4665 basic architecture (such as MIPS and SH), you may now set the
4666 architecture explicitly. "set arch" sets, "info arch" lists
4667 the possible architectures.
4669 *** Changes in GDB-4.16:
4671 * New native configurations
4673 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4674 M68K NetBSD m68k-*-netbsd*
4675 PowerPC AIX 4.x powerpc-*-aix*
4676 PowerPC MacOS powerpc-*-macos*
4677 PowerPC Windows NT powerpcle-*-cygwin32
4678 RS/6000 AIX 4.x rs6000-*-aix4*
4682 ARM with RDP protocol arm-*-*
4683 I960 with MON960 i960-*-coff
4684 MIPS VxWorks mips*-*-vxworks*
4685 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4686 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4688 Matra Sparclet sparclet-*-*
4692 The powerpc-eabi configuration now includes the PSIM simulator,
4693 contributed by Andrew Cagney, with assistance from Mike Meissner.
4694 PSIM is a very elaborate model of the PowerPC, including not only
4695 basic instruction set execution, but also details of execution unit
4696 performance and I/O hardware. See sim/ppc/README for more details.
4700 GDB now works with Solaris 2.5.
4702 * Windows 95/NT native
4704 GDB will now work as a native debugger on Windows 95 and Windows NT.
4705 To build it from source, you must use the "gnu-win32" environment,
4706 which uses a DLL to emulate enough of Unix to run the GNU tools.
4707 Further information, binaries, and sources are available at
4708 ftp.cygnus.com, under pub/gnu-win32.
4710 * dont-repeat command
4712 If a user-defined command includes the command `dont-repeat', then the
4713 command will not be repeated if the user just types return. This is
4714 useful if the command is time-consuming to run, so that accidental
4715 extra keystrokes don't run the same command many times.
4717 * Send break instead of ^C
4719 The standard remote protocol now includes an option to send a break
4720 rather than a ^C to the target in order to interrupt it. By default,
4721 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4723 * Remote protocol timeout
4725 The standard remote protocol includes a new variable `remotetimeout'
4726 that allows you to set the number of seconds before GDB gives up trying
4727 to read from the target. The default value is 2.
4729 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4731 By default GDB will automatically keep track of objects as they are
4732 loaded and unloaded by the dynamic linker. By using the command `set
4733 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4734 when shared library events occur, thus allowing you to set breakpoints
4735 in shared libraries which are explicitly loaded by the inferior.
4737 Note this feature does not work on hpux8. On hpux9 you must link
4738 /usr/lib/end.o into your program. This feature should work
4739 automatically on hpux10.
4741 * Irix 5.x hardware watchpoint support
4743 Irix 5 configurations now support the use of hardware watchpoints.
4745 * Mips protocol "SYN garbage limit"
4747 When debugging a Mips target using the `target mips' protocol, you
4748 may set the number of characters that GDB will ignore by setting
4749 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4750 every character. The default value is 1050.
4752 * Recording and replaying remote debug sessions
4754 If you set `remotelogfile' to the name of a file, gdb will write to it
4755 a recording of a remote debug session. This recording may then be
4756 replayed back to gdb using "gdbreplay". See gdbserver/README for
4757 details. This is useful when you have a problem with GDB while doing
4758 remote debugging; you can make a recording of the session and send it
4759 to someone else, who can then recreate the problem.
4761 * Speedups for remote debugging
4763 GDB includes speedups for downloading and stepping MIPS systems using
4764 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4765 and more efficient S-record downloading.
4767 * Memory use reductions and statistics collection
4769 GDB now uses less memory and reports statistics about memory usage.
4770 Try the `maint print statistics' command, for example.
4772 *** Changes in GDB-4.15:
4774 * Psymtabs for XCOFF
4776 The symbol reader for AIX GDB now uses partial symbol tables. This
4777 can greatly improve startup time, especially for large executables.
4779 * Remote targets use caching
4781 Remote targets now use a data cache to speed up communication with the
4782 remote side. The data cache could lead to incorrect results because
4783 it doesn't know about volatile variables, thus making it impossible to
4784 debug targets which use memory mapped I/O devices. `set remotecache
4785 off' turns the the data cache off.
4787 * Remote targets may have threads
4789 The standard remote protocol now includes support for multiple threads
4790 in the target system, using new protocol commands 'H' and 'T'. See
4791 gdb/remote.c for details.
4795 If GDB is configured with `--enable-netrom', then it will include
4796 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4797 acts as though it is a bank of ROM on the target board, but you can
4798 write into it over the network. GDB's support consists only of
4799 support for fast loading into the emulated ROM; to debug, you must use
4800 another protocol, such as standard remote protocol. The usual
4801 sequence is something like
4803 target nrom <netrom-hostname>
4805 target remote <netrom-hostname>:1235
4809 GDB now includes support for the Apple Macintosh, as a host only. It
4810 may be run as either an MPW tool or as a standalone application, and
4811 it can debug through the serial port. All the usual GDB commands are
4812 available, but to the target command, you must supply "serial" as the
4813 device type instead of "/dev/ttyXX". See mpw-README in the main
4814 directory for more information on how to build. The MPW configuration
4815 scripts */mpw-config.in support only a few targets, and only the
4816 mips-idt-ecoff target has been tested.
4820 GDB configuration now uses autoconf. This is not user-visible,
4821 but does simplify configuration and building.
4825 GDB now supports hpux10.
4827 *** Changes in GDB-4.14:
4829 * New native configurations
4831 x86 FreeBSD i[345]86-*-freebsd
4832 x86 NetBSD i[345]86-*-netbsd
4833 NS32k NetBSD ns32k-*-netbsd
4834 Sparc NetBSD sparc-*-netbsd
4838 A29K VxWorks a29k-*-vxworks
4839 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4840 CPU32 EST-300 emulator m68*-*-est*
4841 PowerPC ELF powerpc-*-elf
4844 * Alpha OSF/1 support for procfs
4846 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4847 possible to attach to running processes. As the mounting of the /proc
4848 filesystem is optional on the Alpha, GDB automatically determines
4849 the availability of /proc during startup. This can lead to problems
4850 if /proc is unmounted after GDB has been started.
4852 * Arguments to user-defined commands
4854 User commands may accept up to 10 arguments separated by whitespace.
4855 Arguments are accessed within the user command via $arg0..$arg9. A
4858 print $arg0 + $arg1 + $arg2
4860 To execute the command use:
4863 Defines the command "adder" which prints the sum of its three arguments.
4864 Note the arguments are text substitutions, so they may reference variables,
4865 use complex expressions, or even perform inferior function calls.
4867 * New `if' and `while' commands
4869 This makes it possible to write more sophisticated user-defined
4870 commands. Both commands take a single argument, which is the
4871 expression to evaluate, and must be followed by the commands to
4872 execute, one per line, if the expression is nonzero, the list being
4873 terminated by the word `end'. The `if' command list may include an
4874 `else' word, which causes the following commands to be executed only
4875 if the expression is zero.
4877 * Fortran source language mode
4879 GDB now includes partial support for Fortran 77. It will recognize
4880 Fortran programs and can evaluate a subset of Fortran expressions, but
4881 variables and functions may not be handled correctly. GDB will work
4882 with G77, but does not yet know much about symbols emitted by other
4885 * Better HPUX support
4887 Most debugging facilities now work on dynamic executables for HPPAs
4888 running hpux9 or later. You can attach to running dynamically linked
4889 processes, but by default the dynamic libraries will be read-only, so
4890 for instance you won't be able to put breakpoints in them. To change
4891 that behavior do the following before running the program:
4897 This will cause the libraries to be mapped private and read-write.
4898 To revert to the normal behavior, do this:
4904 You cannot set breakpoints or examine data in the library until after
4905 the library is loaded if the function/data symbols do not have
4908 GDB can now also read debug symbols produced by the HP C compiler on
4909 HPPAs (sorry, no C++, Fortran or 68k support).
4911 * Target byte order now dynamically selectable
4913 You can choose which byte order to use with a target system, via the
4914 commands "set endian big" and "set endian little", and you can see the
4915 current setting by using "show endian". You can also give the command
4916 "set endian auto", in which case GDB will use the byte order
4917 associated with the executable. Currently, only embedded MIPS
4918 configurations support dynamic selection of target byte order.
4920 * New DOS host serial code
4922 This version uses DPMI interrupts to handle buffered I/O, so you
4923 no longer need to run asynctsr when debugging boards connected to
4926 *** Changes in GDB-4.13:
4928 * New "complete" command
4930 This lists all the possible completions for the rest of the line, if it
4931 were to be given as a command itself. This is intended for use by emacs.
4933 * Trailing space optional in prompt
4935 "set prompt" no longer adds a space for you after the prompt you set. This
4936 allows you to set a prompt which ends in a space or one that does not.
4938 * Breakpoint hit counts
4940 "info break" now displays a count of the number of times the breakpoint
4941 has been hit. This is especially useful in conjunction with "ignore"; you
4942 can ignore a large number of breakpoint hits, look at the breakpoint info
4943 to see how many times the breakpoint was hit, then run again, ignoring one
4944 less than that number, and this will get you quickly to the last hit of
4947 * Ability to stop printing at NULL character
4949 "set print null-stop" will cause GDB to stop printing the characters of
4950 an array when the first NULL is encountered. This is useful when large
4951 arrays actually contain only short strings.
4953 * Shared library breakpoints
4955 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4956 breakpoints in shared libraries before the executable is run.
4958 * Hardware watchpoints
4960 There is a new hardware breakpoint for the watch command for sparclite
4961 targets. See gdb/sparclite/hw_breakpoint.note.
4963 Hardware watchpoints are also now supported under GNU/Linux.
4967 Annotations have been added. These are for use with graphical interfaces,
4968 and are still experimental. Currently only gdba.el uses these.
4970 * Improved Irix 5 support
4972 GDB now works properly with Irix 5.2.
4974 * Improved HPPA support
4976 GDB now works properly with the latest GCC and GAS.
4978 * New native configurations
4980 Sequent PTX4 i[34]86-sequent-ptx4
4981 HPPA running OSF/1 hppa*-*-osf*
4982 Atari TT running SVR4 m68*-*-sysv4*
4983 RS/6000 LynxOS rs6000-*-lynxos*
4987 OS/9000 i[34]86-*-os9k
4988 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4991 * Hitachi SH7000 and E7000-PC ICE support
4993 There is now support for communicating with the Hitachi E7000-PC ICE.
4994 This is available automatically when GDB is configured for the SH.
4998 As usual, a variety of small fixes and improvements, both generic
4999 and configuration-specific. See the ChangeLog for more detail.
5001 *** Changes in GDB-4.12:
5003 * Irix 5 is now supported
5007 GDB-4.12 on the HPPA has a number of changes which make it unable
5008 to debug the output from the currently released versions of GCC and
5009 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5010 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5011 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5014 *** Changes in GDB-4.11:
5016 * User visible changes:
5020 The "set remotedebug" option is now consistent between the mips remote
5021 target, remote targets using the gdb-specific protocol, UDI (AMD's
5022 debug protocol for the 29k) and the 88k bug monitor. It is now an
5023 integer specifying a debug level (normally 0 or 1, but 2 means more
5024 debugging info for the mips target).
5026 * DEC Alpha native support
5028 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5029 debug info, but GDB works fairly well with the DEC compiler and should
5030 work with a future GCC release. See the README file for a few
5031 Alpha-specific notes.
5033 * Preliminary thread implementation
5035 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5037 * LynxOS native and target support for 386
5039 This release has been hosted on LynxOS 2.2, and also can be configured
5040 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5043 * Improvements in C++ mangling/demangling.
5045 This release has much better g++ debugging, specifically in name
5046 mangling/demangling, virtual function calls, print virtual table,
5047 call methods, ...etc.
5049 *** Changes in GDB-4.10:
5051 * User visible changes:
5053 Remote debugging using the GDB-specific (`target remote') protocol now
5054 supports the `load' command. This is only useful if you have some
5055 other way of getting the stub to the target system, and you can put it
5056 somewhere in memory where it won't get clobbered by the download.
5058 Filename completion now works.
5060 When run under emacs mode, the "info line" command now causes the
5061 arrow to point to the line specified. Also, "info line" prints
5062 addresses in symbolic form (as well as hex).
5064 All vxworks based targets now support a user settable option, called
5065 vxworks-timeout. This option represents the number of seconds gdb
5066 should wait for responses to rpc's. You might want to use this if
5067 your vxworks target is, perhaps, a slow software simulator or happens
5068 to be on the far side of a thin network line.
5072 This release contains support for using a DEC alpha as a GDB host for
5073 cross debugging. Native alpha debugging is not supported yet.
5076 *** Changes in GDB-4.9:
5080 This is the first GDB release which is accompanied by a matching testsuite.
5081 The testsuite requires installation of dejagnu, which should be available
5082 via ftp from most sites that carry GNU software.
5086 'Cfront' style demangling has had its name changed to 'ARM' style, to
5087 emphasize that it was written from the specifications in the C++ Annotated
5088 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5089 disclaimers, it still generated too much confusion with users attempting to
5090 use gdb with AT&T cfront.
5094 GDB now uses a standard remote interface to a simulator library.
5095 So far, the library contains simulators for the Zilog Z8001/2, the
5096 Hitachi H8/300, H8/500 and Super-H.
5098 * New targets supported
5100 H8/300 simulator h8300-hitachi-hms or h8300hms
5101 H8/500 simulator h8500-hitachi-hms or h8500hms
5102 SH simulator sh-hitachi-hms or sh
5103 Z8000 simulator z8k-zilog-none or z8ksim
5104 IDT MIPS board over serial line mips-idt-ecoff
5106 Cross-debugging to GO32 targets is supported. It requires a custom
5107 version of the i386-stub.c module which is integrated with the
5108 GO32 memory extender.
5110 * New remote protocols
5112 MIPS remote debugging protocol.
5114 * New source languages supported
5116 This version includes preliminary support for Chill, a Pascal like language
5117 used by telecommunications companies. Chill support is also being integrated
5118 into the GNU compiler, but we don't know when it will be publically available.
5121 *** Changes in GDB-4.8:
5123 * HP Precision Architecture supported
5125 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5126 version of this support was available as a set of patches from the
5127 University of Utah. GDB does not support debugging of programs
5128 compiled with the HP compiler, because HP will not document their file
5129 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5130 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5132 Many problems in the preliminary version have been fixed.
5134 * Faster and better demangling
5136 We have improved template demangling and fixed numerous bugs in the GNU style
5137 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5138 character types (wchar_t) are now supported. Demangling of each symbol is now
5139 only done once, and is cached when the symbol table for a file is read in.
5140 This results in a small increase in memory usage for C programs, a moderate
5141 increase in memory usage for C++ programs, and a fantastic speedup in
5144 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5145 from the specifications in the Annotated Reference Manual, which AT&T's
5146 compiler does not actually implement.
5148 * G++ multiple inheritance compiler problem
5150 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5151 inheritance lattices was reworked to properly discover ambiguities. We
5152 recently found an example which causes this new algorithm to fail in a
5153 very subtle way, producing bad debug information for those classes.
5154 The file 'gcc.patch' (in this directory) can be applied to gcc to
5155 circumvent the problem. A future GCC release will contain a complete
5158 The previous G++ debug info problem (mentioned below for the gdb-4.7
5159 release) is fixed in gcc version 2.3.2.
5161 * Improved configure script
5163 The `configure' script will now attempt to guess your system type if
5164 you don't supply a host system type. The old scheme of supplying a
5165 host system triplet is preferable over using this. All the magic is
5166 done in the new `config.guess' script. Examine it for details.
5168 We have also brought our configure script much more in line with the FSF's
5169 version. It now supports the --with-xxx options. In particular,
5170 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5171 The resulting GDB will not be able to read arbitrary object file formats --
5172 only the format ``expected'' to be used on the configured target system.
5173 We hope to make this the default in a future release.
5175 * Documentation improvements
5177 There's new internal documentation on how to modify GDB, and how to
5178 produce clean changes to the code. We implore people to read it
5179 before submitting changes.
5181 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5182 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5183 `info' files are also provided. To build `info' files from scratch,
5184 you will need the latest `makeinfo' release, which will be available in
5185 a future texinfo-X.Y release.
5187 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5188 We're not sure exactly which versions have this problem, but it has
5189 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5190 or better. If that isn't possible, there is a patch in
5191 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5192 around this problem.
5196 GDB now supports array constants that can be used in expressions typed in by
5197 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5198 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5201 The new directory `gdb/sparclite' contains a program that demonstrates
5202 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5204 * New native hosts supported
5206 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5207 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5209 * New targets supported
5211 AMD 29k family via UDI a29k-amd-udi or udi29k
5213 * New file formats supported
5215 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5216 HPUX core files, and SCO 3.2v2 core files.
5220 Attaching to processes now works again; thanks for the many bug reports.
5222 We have also stomped on a bunch of core dumps caused by
5223 printf_filtered("%s") problems.
5225 We eliminated a copyright problem on the rpc and ptrace header files
5226 for VxWorks, which was discovered at the last minute during the 4.7
5227 release. You should now be able to build a VxWorks GDB.
5229 You can now interrupt gdb while an attached process is running. This
5230 will cause the attached process to stop, and give control back to GDB.
5232 We fixed problems caused by using too many file descriptors
5233 for reading symbols from object files and libraries. This was
5234 especially a problem for programs that used many (~100) shared
5237 The `step' command now only enters a subroutine if there is line number
5238 information for the subroutine. Otherwise it acts like the `next'
5239 command. Previously, `step' would enter subroutines if there was
5240 any debugging information about the routine. This avoids problems
5241 when using `cc -g1' on MIPS machines.
5243 * Internal improvements
5245 GDB's internal interfaces have been improved to make it easier to support
5246 debugging of multiple languages in the future.
5248 GDB now uses a common structure for symbol information internally.
5249 Minimal symbols (derived from linkage symbols in object files), partial
5250 symbols (from a quick scan of debug information), and full symbols
5251 contain a common subset of information, making it easier to write
5252 shared code that handles any of them.
5254 * New command line options
5256 We now accept --silent as an alias for --quiet.
5260 The memory-mapped-malloc library is now licensed under the GNU Library
5261 General Public License.
5263 *** Changes in GDB-4.7:
5265 * Host/native/target split
5267 GDB has had some major internal surgery to untangle the support for
5268 hosts and remote targets. Now, when you configure GDB for a remote
5269 target, it will no longer load in all of the support for debugging
5270 local programs on the host. When fully completed and tested, this will
5271 ensure that arbitrary host/target combinations are possible.
5273 The primary conceptual shift is to separate the non-portable code in
5274 GDB into three categories. Host specific code is required any time GDB
5275 is compiled on that host, regardless of the target. Target specific
5276 code relates to the peculiarities of the target, but can be compiled on
5277 any host. Native specific code is everything else: it can only be
5278 built when the host and target are the same system. Child process
5279 handling and core file support are two common `native' examples.
5281 GDB's use of /proc for controlling Unix child processes is now cleaner.
5282 It has been split out into a single module under the `target_ops' vector,
5283 plus two native-dependent functions for each system that uses /proc.
5285 * New hosts supported
5287 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5288 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5289 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5291 * New targets supported
5293 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5294 68030 and CPU32 m68030-*-*, m68332-*-*
5296 * New native hosts supported
5298 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5299 (386bsd is not well tested yet)
5300 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5302 * New file formats supported
5304 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5305 supports reading of `a.out.adobe' object files, which are an a.out
5306 format extended with minimal information about multiple sections.
5310 `show copying' is the same as the old `info copying'.
5311 `show warranty' is the same as `info warrantee'.
5312 These were renamed for consistency. The old commands continue to work.
5314 `info handle' is a new alias for `info signals'.
5316 You can now define pre-command hooks, which attach arbitrary command
5317 scripts to any command. The commands in the hook will be executed
5318 prior to the user's command. You can also create a hook which will be
5319 executed whenever the program stops. See gdb.texinfo.
5323 We now deal with Cfront style name mangling, and can even extract type
5324 info from mangled symbols. GDB can automatically figure out which
5325 symbol mangling style your C++ compiler uses.
5327 Calling of methods and virtual functions has been improved as well.
5331 The crash that occured when debugging Sun Ansi-C compiled binaries is
5332 fixed. This was due to mishandling of the extra N_SO stabs output
5335 We also finally got Ultrix 4.2 running in house, and fixed core file
5336 support, with help from a dozen people on the net.
5338 John M. Farrell discovered that the reason that single-stepping was so
5339 slow on all of the Mips based platforms (primarily SGI and DEC) was
5340 that we were trying to demangle and lookup a symbol used for internal
5341 purposes on every instruction that was being stepped through. Changing
5342 the name of that symbol so that it couldn't be mistaken for a C++
5343 mangled symbol sped things up a great deal.
5345 Rich Pixley sped up symbol lookups in general by getting much smarter
5346 about when C++ symbol mangling is necessary. This should make symbol
5347 completion (TAB on the command line) much faster. It's not as fast as
5348 we'd like, but it's significantly faster than gdb-4.6.
5352 A new user controllable variable 'call_scratch_address' can
5353 specify the location of a scratch area to be used when GDB
5354 calls a function in the target. This is necessary because the
5355 usual method of putting the scratch area on the stack does not work
5356 in systems that have separate instruction and data spaces.
5358 We integrated changes to support the 29k UDI (Universal Debugger
5359 Interface), but discovered at the last minute that we didn't have all
5360 of the appropriate copyright paperwork. We are working with AMD to
5361 resolve this, and hope to have it available soon.
5365 We have sped up the remote serial line protocol, especially for targets
5366 with lots of registers. It now supports a new `expedited status' ('T')
5367 message which can be used in place of the existing 'S' status message.
5368 This allows the remote stub to send only the registers that GDB
5369 needs to make a quick decision about single-stepping or conditional
5370 breakpoints, eliminating the need to fetch the entire register set for
5371 each instruction being stepped through.
5373 The GDB remote serial protocol now implements a write-through cache for
5374 registers, only re-reading the registers if the target has run.
5376 There is also a new remote serial stub for SPARC processors. You can
5377 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5378 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5379 processor with a serial port.
5383 Configure.in files have become much easier to read and modify. A new
5384 `table driven' format makes it more obvious what configurations are
5385 supported, and what files each one uses.
5389 There is a new opcodes library which will eventually contain all of the
5390 disassembly routines and opcode tables. At present, it only contains
5391 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5392 disassembler (binutils/objdump) to share these routines.
5394 The libiberty library is now copylefted under the GNU Library General
5395 Public License. This allows more liberal use, and was done so libg++
5396 can use it. This makes no difference to GDB, since the Library License
5397 grants all the rights from the General Public License.
5401 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5402 reference to the stabs symbol info used by the debugger. It is (as far
5403 as we know) the only published document on this fascinating topic. We
5404 encourage you to read it, compare it to the stabs information on your
5405 system, and send improvements on the document in general (to
5406 bug-gdb@prep.ai.mit.edu).
5408 And, of course, many bugs have been fixed.
5411 *** Changes in GDB-4.6:
5413 * Better support for C++ function names
5415 GDB now accepts as input the "demangled form" of C++ overloaded function
5416 names and member function names, and can do command completion on such names
5417 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5418 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5419 Make use of command completion, it is your friend.
5421 GDB also now accepts a variety of C++ mangled symbol formats. They are
5422 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5423 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5424 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5425 for the list of formats.
5427 * G++ symbol mangling problem
5429 Recent versions of gcc have a bug in how they emit debugging information for
5430 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5431 directory) can be applied to gcc to fix the problem. Alternatively, if you
5432 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5433 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5434 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5437 * New 'maintenance' command
5439 All of the commands related to hacking GDB internals have been moved out of
5440 the main command set, and now live behind the 'maintenance' command. This
5441 can also be abbreviated as 'mt'. The following changes were made:
5443 dump-me -> maintenance dump-me
5444 info all-breakpoints -> maintenance info breakpoints
5445 printmsyms -> maintenance print msyms
5446 printobjfiles -> maintenance print objfiles
5447 printpsyms -> maintenance print psymbols
5448 printsyms -> maintenance print symbols
5450 The following commands are new:
5452 maintenance demangle Call internal GDB demangler routine to
5453 demangle a C++ link name and prints the result.
5454 maintenance print type Print a type chain for a given symbol
5456 * Change to .gdbinit file processing
5458 We now read the $HOME/.gdbinit file before processing the argv arguments
5459 (e.g. reading symbol files or core files). This allows global parameters to
5460 be set, which will apply during the symbol reading. The ./.gdbinit is still
5461 read after argv processing.
5463 * New hosts supported
5465 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5467 GNU/Linux support i386-unknown-linux or linux
5469 We are also including code to support the HP/PA running BSD and HPUX. This
5470 is almost guaranteed not to work, as we didn't have time to test or build it
5471 for this release. We are including it so that the more adventurous (or
5472 masochistic) of you can play with it. We also had major problems with the
5473 fact that the compiler that we got from HP doesn't support the -g option.
5476 * New targets supported
5478 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5480 * More smarts about finding #include files
5482 GDB now remembers the compilation directory for all include files, and for
5483 all files from which C is generated (like yacc and lex sources). This
5484 greatly improves GDB's ability to find yacc/lex sources, and include files,
5485 especially if you are debugging your program from a directory different from
5486 the one that contains your sources.
5488 We also fixed a bug which caused difficulty with listing and setting
5489 breakpoints in include files which contain C code. (In the past, you had to
5490 try twice in order to list an include file that you hadn't looked at before.)
5492 * Interesting infernals change
5494 GDB now deals with arbitrary numbers of sections, where the symbols for each
5495 section must be relocated relative to that section's landing place in the
5496 target's address space. This work was needed to support ELF with embedded
5497 stabs used by Solaris-2.0.
5499 * Bug fixes (of course!)
5501 There have been loads of fixes for the following things:
5502 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5503 i960, stabs, DOS(GO32), procfs, etc...
5505 See the ChangeLog for details.
5507 *** Changes in GDB-4.5:
5509 * New machines supported (host and target)
5511 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5513 SGI Irix-4.x mips-sgi-irix4 or iris4
5515 * New malloc package
5517 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5518 Mmalloc is capable of handling mutiple heaps of memory. It is also
5519 capable of saving a heap to a file, and then mapping it back in later.
5520 This can be used to greatly speedup the startup of GDB by using a
5521 pre-parsed symbol table which lives in a mmalloc managed heap. For
5522 more details, please read mmalloc/mmalloc.texi.
5526 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5527 'help info proc' for details.
5529 * MIPS ecoff symbol table format
5531 The code that reads MIPS symbol table format is now supported on all hosts.
5532 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5535 * File name changes for MS-DOS
5537 Many files in the config directories have been renamed to make it easier to
5538 support GDB on MS-DOSe systems (which have very restrictive file name
5539 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5540 environment) is close to working but has some remaining problems. Note
5541 that debugging of DOS programs is not supported, due to limitations
5542 in the ``operating system'', but it can be used to host cross-debugging.
5544 * Cross byte order fixes
5546 Many fixes have been made to support cross debugging of Sparc and MIPS
5547 targets from hosts whose byte order differs.
5549 * New -mapped and -readnow options
5551 If memory-mapped files are available on your system through the 'mmap'
5552 system call, you can use the -mapped option on the `file' or
5553 `symbol-file' commands to cause GDB to write the symbols from your
5554 program into a reusable file. If the program you are debugging is
5555 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5556 Future GDB debugging sessions will notice the presence of this file,
5557 and will quickly map in symbol information from it, rather than reading
5558 the symbol table from the executable program. Using the '-mapped'
5559 option in a GDB `file' or `symbol-file' command has the same effect as
5560 starting GDB with the '-mapped' command-line option.
5562 You can cause GDB to read the entire symbol table immediately by using
5563 the '-readnow' option with any of the commands that load symbol table
5564 information (or on the GDB command line). This makes the command
5565 slower, but makes future operations faster.
5567 The -mapped and -readnow options are typically combined in order to
5568 build a `fred.syms' file that contains complete symbol information.
5569 A simple GDB invocation to do nothing but build a `.syms' file for future
5572 gdb -batch -nx -mapped -readnow programname
5574 The `.syms' file is specific to the host machine on which GDB is run.
5575 It holds an exact image of GDB's internal symbol table. It cannot be
5576 shared across multiple host platforms.
5578 * longjmp() handling
5580 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5581 siglongjmp() without losing control. This feature has not yet been ported to
5582 all systems. It currently works on many 386 platforms, all MIPS-based
5583 platforms (SGI, DECstation, etc), and Sun3/4.
5587 Preliminary work has been put in to support the new Solaris OS from Sun. At
5588 this time, it can control and debug processes, but it is not capable of
5593 As always, many many bug fixes. The major areas were with g++, and mipsread.
5594 People using the MIPS-based platforms should experience fewer mysterious
5595 crashes and trashed symbol tables.
5597 *** Changes in GDB-4.4:
5599 * New machines supported (host and target)
5601 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5603 BSD Reno on Vax vax-dec-bsd
5604 Ultrix on Vax vax-dec-ultrix
5606 * New machines supported (target)
5608 AMD 29000 embedded, using EBMON a29k-none-none
5612 GDB continues to improve its handling of C++. `References' work better.
5613 The demangler has also been improved, and now deals with symbols mangled as
5614 per the Annotated C++ Reference Guide.
5616 GDB also now handles `stabs' symbol information embedded in MIPS
5617 `ecoff' symbol tables. Since the ecoff format was not easily
5618 extensible to handle new languages such as C++, this appeared to be a
5619 good way to put C++ debugging info into MIPS binaries. This option
5620 will be supported in the GNU C compiler, version 2, when it is
5623 * New features for SVR4
5625 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5626 shared libraries. Debugging dynamically linked programs should present
5627 only minor differences from debugging statically linked programs.
5629 The `info proc' command will print out information about any process
5630 on an SVR4 system (including the one you are debugging). At the moment,
5631 it prints the address mappings of the process.
5633 If you bring up GDB on another SVR4 system, please send mail to
5634 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5636 * Better dynamic linking support in SunOS
5638 Reading symbols from shared libraries which contain debugging symbols
5639 now works properly. However, there remain issues such as automatic
5640 skipping of `transfer vector' code during function calls, which
5641 make it harder to debug code in a shared library, than to debug the
5642 same code linked statically.
5646 GDB is now using the latest `getopt' routines from the FSF. This
5647 version accepts the -- prefix for options with long names. GDB will
5648 continue to accept the old forms (-option and +option) as well.
5649 Various single letter abbreviations for options have been explicity
5650 added to the option table so that they won't get overshadowed in the
5651 future by other options that begin with the same letter.
5655 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5656 Many assorted bugs have been handled. Many more remain to be handled.
5657 See the various ChangeLog files (primarily in gdb and bfd) for details.
5660 *** Changes in GDB-4.3:
5662 * New machines supported (host and target)
5664 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5665 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5666 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5668 * Almost SCO Unix support
5670 We had hoped to support:
5671 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5672 (except for core file support), but we discovered very late in the release
5673 that it has problems with process groups that render gdb unusable. Sorry
5674 about that. I encourage people to fix it and post the fixes.
5676 * Preliminary ELF and DWARF support
5678 GDB can read ELF object files on System V Release 4, and can handle
5679 debugging records for C, in DWARF format, in ELF files. This support
5680 is preliminary. If you bring up GDB on another SVR4 system, please
5681 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5686 GDB now uses the latest `readline' library. One user-visible change
5687 is that two tabs will list possible command completions, which previously
5688 required typing M-? (meta-question mark, or ESC ?).
5692 The `stepi' bug that many of you noticed has been squashed.
5693 Many bugs in C++ have been handled. Many more remain to be handled.
5694 See the various ChangeLog files (primarily in gdb and bfd) for details.
5696 * State of the MIPS world (in case you wondered):
5698 GDB can understand the symbol tables emitted by the compilers
5699 supplied by most vendors of MIPS-based machines, including DEC. These
5700 symbol tables are in a format that essentially nobody else uses.
5702 Some versions of gcc come with an assembler post-processor called
5703 mips-tfile. This program is required if you want to do source-level
5704 debugging of gcc-compiled programs. I believe FSF does not ship
5705 mips-tfile with gcc version 1, but it will eventually come with gcc
5708 Debugging of g++ output remains a problem. g++ version 1.xx does not
5709 really support it at all. (If you're lucky, you should be able to get
5710 line numbers and stack traces to work, but no parameters or local
5711 variables.) With some work it should be possible to improve the
5714 When gcc version 2 is released, you will have somewhat better luck.
5715 However, even then you will get confusing results for inheritance and
5718 We will eventually provide full debugging of g++ output on
5719 DECstations. This will probably involve some kind of stabs-in-ecoff
5720 encapulation, but the details have not been worked out yet.
5723 *** Changes in GDB-4.2:
5725 * Improved configuration
5727 Only one copy of `configure' exists now, and it is not self-modifying.
5728 Porting BFD is simpler.
5732 The `step' and `next' commands now only stop at the first instruction
5733 of a source line. This prevents the multiple stops that used to occur
5734 in switch statements, for-loops, etc. `Step' continues to stop if a
5735 function that has debugging information is called within the line.
5739 Lots of small bugs fixed. More remain.
5741 * New host supported (not target)
5743 Intel 386 PC clone running Mach i386-none-mach
5746 *** Changes in GDB-4.1:
5748 * Multiple source language support
5750 GDB now has internal scaffolding to handle several source languages.
5751 It determines the type of each source file from its filename extension,
5752 and will switch expression parsing and number formatting to match the
5753 language of the function in the currently selected stack frame.
5754 You can also specifically set the language to be used, with
5755 `set language c' or `set language modula-2'.
5759 GDB now has preliminary support for the GNU Modula-2 compiler,
5760 currently under development at the State University of New York at
5761 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5762 continue through the fall of 1991 and into 1992.
5764 Other Modula-2 compilers are currently not supported, and attempting to
5765 debug programs compiled with them will likely result in an error as the
5766 symbol table is read. Feel free to work on it, though!
5768 There are hooks in GDB for strict type checking and range checking,
5769 in the `Modula-2 philosophy', but they do not currently work.
5773 GDB can now write to executable and core files (e.g. patch
5774 a variable's value). You must turn this switch on, specify
5775 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5776 by assigning a new value to a variable. Modifications take
5779 * Automatic SunOS shared library reading
5781 When you run your program, GDB automatically determines where its
5782 shared libraries (if any) have been loaded, and reads their symbols.
5783 The `share' command is no longer needed. This also works when
5784 examining core files.
5788 You can specify the number of lines that the `list' command shows.
5791 * New machines supported (host and target)
5793 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5794 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5795 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5797 * New hosts supported (not targets)
5799 IBM RT/PC: romp-ibm-aix or rtpc
5801 * New targets supported (not hosts)
5803 AMD 29000 embedded with COFF a29k-none-coff
5804 AMD 29000 embedded with a.out a29k-none-aout
5805 Ultracomputer remote kernel debug a29k-nyu-kern
5807 * New remote interfaces
5813 *** Changes in GDB-4.0:
5817 Wide output is wrapped at good places to make the output more readable.
5819 Gdb now supports cross-debugging from a host machine of one type to a
5820 target machine of another type. Communication with the target system
5821 is over serial lines. The ``target'' command handles connecting to the
5822 remote system; the ``load'' command will download a program into the
5823 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5824 also supports debugging of realtime processes running under VxWorks,
5825 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5826 stub on the target system.
5828 New CPUs supported include the AMD 29000 and Intel 960.
5830 GDB now reads object files and symbol tables via a ``binary file''
5831 library, which allows a single copy of GDB to debug programs of multiple
5832 object file types such as a.out and coff.
5834 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5835 refcard.dvi and refcard.ps are available to format it).
5838 * Control-Variable user interface simplified
5840 All variables that control the operation of the debugger can be set
5841 by the ``set'' command, and displayed by the ``show'' command.
5843 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5844 ``Show prompt'' produces the response:
5845 Gdb's prompt is new-gdb=>.
5847 What follows are the NEW set commands. The command ``help set'' will
5848 print a complete list of old and new set commands. ``help set FOO''
5849 will give a longer description of the variable FOO. ``show'' will show
5850 all of the variable descriptions and their current settings.
5852 confirm on/off: Enables warning questions for operations that are
5853 hard to recover from, e.g. rerunning the program while
5854 it is already running. Default is ON.
5856 editing on/off: Enables EMACS style command line editing
5857 of input. Previous lines can be recalled with
5858 control-P, the current line can be edited with control-B,
5859 you can search for commands with control-R, etc.
5862 history filename NAME: NAME is where the gdb command history
5863 will be stored. The default is .gdb_history,
5864 or the value of the environment variable
5867 history size N: The size, in commands, of the command history. The
5868 default is 256, or the value of the environment variable
5871 history save on/off: If this value is set to ON, the history file will
5872 be saved after exiting gdb. If set to OFF, the
5873 file will not be saved. The default is OFF.
5875 history expansion on/off: If this value is set to ON, then csh-like
5876 history expansion will be performed on
5877 command line input. The default is OFF.
5879 radix N: Sets the default radix for input and output. It can be set
5880 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5881 in the current radix, so "set radix 10" is always a no-op.
5883 height N: This integer value is the number of lines on a page. Default
5884 is 24, the current `stty rows'' setting, or the ``li#''
5885 setting from the termcap entry matching the environment
5888 width N: This integer value is the number of characters on a line.
5889 Default is 80, the current `stty cols'' setting, or the ``co#''
5890 setting from the termcap entry matching the environment
5893 Note: ``set screensize'' is obsolete. Use ``set height'' and
5894 ``set width'' instead.
5896 print address on/off: Print memory addresses in various command displays,
5897 such as stack traces and structure values. Gdb looks
5898 more ``symbolic'' if you turn this off; it looks more
5899 ``machine level'' with it on. Default is ON.
5901 print array on/off: Prettyprint arrays. New convenient format! Default
5904 print demangle on/off: Print C++ symbols in "source" form if on,
5907 print asm-demangle on/off: Same, for assembler level printouts
5910 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5913 * Support for Epoch Environment.
5915 The epoch environment is a version of Emacs v18 with windowing. One
5916 new command, ``inspect'', is identical to ``print'', except that if you
5917 are running in the epoch environment, the value is printed in its own
5921 * Support for Shared Libraries
5923 GDB can now debug programs and core files that use SunOS shared libraries.
5924 Symbols from a shared library cannot be referenced
5925 before the shared library has been linked with the program (this
5926 happens after you type ``run'' and before the function main() is entered).
5927 At any time after this linking (including when examining core files
5928 from dynamically linked programs), gdb reads the symbols from each
5929 shared library when you type the ``sharedlibrary'' command.
5930 It can be abbreviated ``share''.
5932 sharedlibrary REGEXP: Load shared object library symbols for files
5933 matching a unix regular expression. No argument
5934 indicates to load symbols for all shared libraries.
5936 info sharedlibrary: Status of loaded shared libraries.
5941 A watchpoint stops execution of a program whenever the value of an
5942 expression changes. Checking for this slows down execution
5943 tremendously whenever you are in the scope of the expression, but is
5944 quite useful for catching tough ``bit-spreader'' or pointer misuse
5945 problems. Some machines such as the 386 have hardware for doing this
5946 more quickly, and future versions of gdb will use this hardware.
5948 watch EXP: Set a watchpoint (breakpoint) for an expression.
5950 info watchpoints: Information about your watchpoints.
5952 delete N: Deletes watchpoint number N (same as breakpoints).
5953 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5954 enable N: Re-enables watchpoint number N (same as breakpoints).
5957 * C++ multiple inheritance
5959 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5962 * C++ exception handling
5964 Gdb now supports limited C++ exception handling. Besides the existing
5965 ability to breakpoint on an exception handler, gdb can breakpoint on
5966 the raising of an exception (before the stack is peeled back to the
5969 catch FOO: If there is a FOO exception handler in the dynamic scope,
5970 set a breakpoint to catch exceptions which may be raised there.
5971 Multiple exceptions (``catch foo bar baz'') may be caught.
5973 info catch: Lists all exceptions which may be caught in the
5974 current stack frame.
5977 * Minor command changes
5979 The command ``call func (arg, arg, ...)'' now acts like the print
5980 command, except it does not print or save a value if the function's result
5981 is void. This is similar to dbx usage.
5983 The ``up'' and ``down'' commands now always print the frame they end up
5984 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5985 frames without printing.
5987 * New directory command
5989 'dir' now adds directories to the FRONT of the source search path.
5990 The path starts off empty. Source files that contain debug information
5991 about the directory in which they were compiled can be found even
5992 with an empty path; Sun CC and GCC include this information. If GDB can't
5993 find your source file in the current directory, type "dir .".
5995 * Configuring GDB for compilation
5997 For normal use, type ``./configure host''. See README or gdb.texinfo
6000 GDB now handles cross debugging. If you are remotely debugging between
6001 two different machines, type ``./configure host -target=targ''.
6002 Host is the machine where GDB will run; targ is the machine
6003 where the program that you are debugging will run.