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.
35 maint print symbol-cache
36 Print the contents of the symbol cache.
38 maint print symbol-cache-statistics
39 Print statistics of symbol cache usage.
41 maint flush-symbol-cache
42 Flush the contents of the symbol cache.
46 Start branch trace recording using Branch Trace Store (BTS) format.
52 Set the maximum number of candidates to be considered during
53 completion. The default value is 200. This limit allows GDB
54 to avoid generating large completion lists, the computation of
55 which can cause the debugger to become temporarily unresponsive.
57 maint set symbol-cache-size
58 maint show symbol-cache-size
59 Control the size of the symbol cache.
61 set|show record btrace bts buffer-size
62 Set and show the size of the ring buffer used for branch tracing in
64 The obtained size may differ from the requested size. Use "info
65 record" to see the obtained buffer size.
67 * The command 'thread apply all' can now support new option '-ascending'
68 to call its specified command for all threads in ascending order.
70 * Python/Guile scripting
72 ** GDB now supports auto-loading of Python/Guile scripts contained in the
73 special section named `.debug_gdb_scripts'.
77 qXfer:btrace-conf:read
78 Return the branch trace configuration for the current thread.
81 Set the requested ring buffer size for branch tracing in BTS format.
84 Indicates a memory breakpoint instruction was executed, irrespective
85 of whether it was GDB that planted the breakpoint or the breakpoint
86 is hardcoded in the program. This is required for correct non-stop
90 Indicates the target stopped for a hardware breakpoint. This is
91 required for correct non-stop mode operation.
94 Return information about files on the remote system.
96 * The info record command now shows the recording format and the
97 branch tracing configuration for the current thread when using
98 the btrace record target.
99 For the BTS format, it shows the ring buffer size.
101 * GDB now has support for DTrace USDT (Userland Static Defined
102 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
104 * GDB now supports access to vector registers on S/390 GNU/Linux
107 * Removed targets and native configurations
109 HP/PA running HP-UX hppa*-*-hpux*
110 Itanium running HP-UX ia64-*-hpux*
112 *** Changes in GDB 7.9
114 * GDB now supports hardware watchpoints on x86 GNU Hurd.
118 ** You can now access frame registers from Python scripts.
119 ** New attribute 'producer' for gdb.Symtab objects.
120 ** gdb.Objfile objects have a new attribute "progspace",
121 which is the gdb.Progspace object of the containing program space.
122 ** gdb.Objfile objects have a new attribute "owner".
123 ** gdb.Objfile objects have a new attribute "build_id",
124 which is the build ID generated when the file was built.
125 ** gdb.Objfile objects have a new method "add_separate_debug_file".
126 ** A new event "gdb.clear_objfiles" has been added, triggered when
127 selecting a new file to debug.
128 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
129 ** New function gdb.lookup_objfile.
131 New events which are triggered when GDB modifies the state of the
134 ** gdb.events.inferior_call_pre: Function call is about to be made.
135 ** gdb.events.inferior_call_post: Function call has just been made.
136 ** gdb.events.memory_changed: A memory location has been altered.
137 ** gdb.events.register_changed: A register has been altered.
139 * New Python-based convenience functions:
141 ** $_caller_is(name [, number_of_frames])
142 ** $_caller_matches(regexp [, number_of_frames])
143 ** $_any_caller_is(name [, number_of_frames])
144 ** $_any_caller_matches(regexp [, number_of_frames])
146 * GDB now supports the compilation and injection of source code into
147 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
148 to compile the source code to object code, and if successful, inject
149 and execute that code within the current context of the inferior.
150 Currently the C language is supported. The commands used to
151 interface with this new feature are:
153 compile code [-raw|-r] [--] [source code]
154 compile file [-raw|-r] filename
158 demangle [-l language] [--] name
159 Demangle "name" in the specified language, or the current language
160 if elided. This command is renamed from the "maint demangle" command.
161 The latter is kept as a no-op to avoid "maint demangle" being interpreted
162 as "maint demangler-warning".
164 queue-signal signal-name-or-number
165 Queue a signal to be delivered to the thread when it is resumed.
167 add-auto-load-scripts-directory directory
168 Add entries to the list of directories from which to load auto-loaded
171 maint print user-registers
172 List all currently available "user" registers.
174 compile code [-r|-raw] [--] [source code]
175 Compile, inject, and execute in the inferior the executable object
176 code produced by compiling the provided source code.
178 compile file [-r|-raw] filename
179 Compile and inject into the inferior the executable object code
180 produced by compiling the source code stored in the filename
183 * On resume, GDB now always passes the signal the program had stopped
184 for to the thread the signal was sent to, even if the user changed
185 threads before resuming. Previously GDB would often (but not
186 always) deliver the signal to the thread that happens to be current
189 * Conversely, the "signal" command now consistently delivers the
190 requested signal to the current thread. GDB now asks for
191 confirmation if the program had stopped for a signal and the user
192 switched threads meanwhile.
194 * "breakpoint always-inserted" modes "off" and "auto" merged.
196 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
197 won't remove breakpoints from the target until all threads stop,
198 even in non-stop mode. The "auto" mode has been removed, and "off"
199 is now the default mode.
203 set debug symbol-lookup
204 show debug symbol-lookup
205 Control display of debugging info regarding symbol lookup.
209 ** The -list-thread-groups command outputs an exit-code field for
210 inferiors that have exited.
214 MIPS SDE mips*-sde*-elf*
218 Support for these obsolete configurations has been removed.
220 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
221 SGI Irix-5.x mips-*-irix5*
222 SGI Irix-6.x mips-*-irix6*
223 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
224 VAX running Ultrix vax-*-ultrix*
226 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
227 and "assf"), have been removed. Use the "sharedlibrary" command, or
228 its alias "share", instead.
230 *** Changes in GDB 7.8
232 * New command line options
235 This is an alias for the --data-directory option.
237 * GDB supports printing and modifying of variable length automatic arrays
238 as specified in ISO C99.
240 * The ARM simulator now supports instruction level tracing
241 with or without disassembly.
245 GDB now has support for scripting using Guile. Whether this is
246 available is determined at configure time.
247 Guile version 2.0 or greater is required.
248 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
250 * New commands (for set/show, see "New options" below)
254 Invoke CODE by passing it to the Guile interpreter.
258 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
260 info auto-load guile-scripts [regexp]
261 Print the list of automatically loaded Guile scripts.
263 * The source command is now capable of sourcing Guile scripts.
264 This feature is dependent on the debugger being built with Guile support.
268 set print symbol-loading (off|brief|full)
269 show print symbol-loading
270 Control whether to print informational messages when loading symbol
271 information for a file. The default is "full", but when debugging
272 programs with large numbers of shared libraries the amount of output
275 set guile print-stack (none|message|full)
276 show guile print-stack
277 Show a stack trace when an error is encountered in a Guile script.
279 set auto-load guile-scripts (on|off)
280 show auto-load guile-scripts
281 Control auto-loading of Guile script files.
283 maint ada set ignore-descriptive-types (on|off)
284 maint ada show ignore-descriptive-types
285 Control whether the debugger should ignore descriptive types in Ada
286 programs. The default is not to ignore the descriptive types. See
287 the user manual for more details on descriptive types and the intended
288 usage of this option.
290 set auto-connect-native-target
292 Control whether GDB is allowed to automatically connect to the
293 native target for the run, attach, etc. commands when not connected
294 to any target yet. See also "target native" below.
296 set record btrace replay-memory-access (read-only|read-write)
297 show record btrace replay-memory-access
298 Control what memory accesses are allowed during replay.
300 maint set target-async (on|off)
301 maint show target-async
302 This controls whether GDB targets operate in synchronous or
303 asynchronous mode. Normally the default is asynchronous, if it is
304 available; but this can be changed to more easily debug problems
305 occurring only in synchronous mode.
307 set mi-async (on|off)
309 Control whether MI asynchronous mode is preferred. This supersedes
310 "set target-async" of previous GDB versions.
312 * "set target-async" is deprecated as a CLI option and is now an alias
313 for "set mi-async" (only puts MI into async mode).
315 * Background execution commands (e.g., "c&", "s&", etc.) are now
316 possible ``out of the box'' if the target supports them. Previously
317 the user would need to explicitly enable the possibility with the
318 "set target-async on" command.
320 * New features in the GDB remote stub, GDBserver
322 ** New option --debug-format=option1[,option2,...] allows one to add
323 additional text to each output. At present only timestamps
324 are supported: --debug-format=timestamps.
325 Timestamps can also be turned on with the
326 "monitor set debug-format timestamps" command from GDB.
328 * The 'record instruction-history' command now starts counting instructions
329 at one. This also affects the instruction ranges reported by the
330 'record function-call-history' command when given the /i modifier.
332 * The command 'record function-call-history' supports a new modifier '/c' to
333 indent the function names based on their call stack depth.
334 The fields for the '/i' and '/l' modifier have been reordered.
335 The source line range is now prefixed with 'at'.
336 The instruction range is now prefixed with 'inst'.
337 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
338 "record instruction-history" and "list" commands.
340 * The ranges given as arguments to the 'record function-call-history' and
341 'record instruction-history' commands are now inclusive.
343 * The btrace record target now supports the 'record goto' command.
344 For locations inside the execution trace, the back trace is computed
345 based on the information stored in the execution trace.
347 * The btrace record target supports limited reverse execution and replay.
348 The target does not record data and therefore does not allow reading
351 * The "catch syscall" command now works on s390*-linux* targets.
353 * The "compare-sections" command is no longer specific to target
354 remote. It now works with all targets.
356 * All native targets are now consistently called "native".
357 Consequently, the "target child", "target GNU", "target djgpp",
358 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
359 commands have been replaced with "target native". The QNX/NTO port
360 leaves the "procfs" target in place and adds a "native" target for
361 consistency with other ports. The impact on users should be minimal
362 as these commands previously either throwed an error, or were
363 no-ops. The target's name is visible in the output of the following
364 commands: "help target", "info target", "info files", "maint print
367 * The "target native" command now connects to the native target. This
368 can be used to launch native programs even when "set
369 auto-connect-native-target" is set to off.
371 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
373 * Support for Intel(R) AVX-512 registers on GNU/Linux.
374 Support displaying and modifying Intel(R) AVX-512 registers
375 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
379 qXfer:btrace:read's annex
380 The qXfer:btrace:read packet supports a new annex 'delta' to read
381 branch trace incrementally.
385 ** Valid Python operations on gdb.Value objects representing
386 structs/classes invoke the corresponding overloaded operators if
388 ** New `Xmethods' feature in the Python API. Xmethods are
389 additional methods or replacements for existing methods of a C++
390 class. This feature is useful for those cases where a method
391 defined in C++ source code could be inlined or optimized out by
392 the compiler, making it unavailable to GDB.
395 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
397 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
398 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
399 its alias "share", instead.
401 * The commands "set remotebaud" and "show remotebaud" are no longer
402 supported. Use "set serial baud" and "show serial baud" (respectively)
407 ** A new option "-gdb-set mi-async" replaces "-gdb-set
408 target-async". The latter is left as a deprecated alias of the
409 former for backward compatibility. If the target supports it,
410 CLI background execution commands are now always possible by
411 default, independently of whether the frontend stated a
412 preference for asynchronous execution with "-gdb-set mi-async".
413 Previously "-gdb-set target-async off" affected both MI execution
414 commands and CLI execution commands.
416 *** Changes in GDB 7.7
418 * Improved support for process record-replay and reverse debugging on
419 arm*-linux* targets. Support for thumb32 and syscall instruction
420 recording has been added.
422 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
424 * GDB now supports Fission DWP file format version 2.
425 http://gcc.gnu.org/wiki/DebugFission
427 * New convenience function "$_isvoid", to check whether an expression
428 is void. A void expression is an expression where the type of the
429 result is "void". For example, some convenience variables may be
430 "void" when evaluated (e.g., "$_exitcode" before the execution of
431 the program being debugged; or an undefined convenience variable).
432 Another example, when calling a function whose return type is
435 * The "maintenance print objfiles" command now takes an optional regexp.
437 * The "catch syscall" command now works on arm*-linux* targets.
439 * GDB now consistently shows "<not saved>" when printing values of
440 registers the debug info indicates have not been saved in the frame
441 and there's nowhere to retrieve them from
442 (callee-saved/call-clobbered registers):
447 (gdb) info registers rax
450 Before, the former would print "<optimized out>", and the latter
451 "*value not available*".
453 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
458 ** Frame filters and frame decorators have been added.
459 ** Temporary breakpoints are now supported.
460 ** Line tables representation has been added.
461 ** New attribute 'parent_type' for gdb.Field objects.
462 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
463 ** New attribute 'name' for gdb.Type objects.
467 Nios II ELF nios2*-*-elf
468 Nios II GNU/Linux nios2*-*-linux
469 Texas Instruments MSP430 msp430*-*-elf
471 * Removed native configurations
473 Support for these a.out NetBSD and OpenBSD obsolete configurations has
474 been removed. ELF variants of these configurations are kept supported.
476 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
477 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
478 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
479 i[34567]86-*-openbsd3.[0-3]
480 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
481 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
482 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
486 Like "catch throw", but catches a re-thrown exception.
488 Renamed from old "maint check-symtabs".
490 Perform consistency checks on symtabs.
492 Expand symtabs matching an optional regexp.
495 Display the details of GDB configure-time options.
497 maint set|show per-command
498 maint set|show per-command space
499 maint set|show per-command time
500 maint set|show per-command symtab
501 Enable display of per-command gdb resource usage.
503 remove-symbol-file FILENAME
504 remove-symbol-file -a ADDRESS
505 Remove a symbol file added via add-symbol-file. The file to remove
506 can be identified by its filename or by an address that lies within
507 the boundaries of this symbol file in memory.
510 info exceptions REGEXP
511 Display the list of Ada exceptions defined in the program being
512 debugged. If provided, only the exceptions whose names match REGEXP
517 set debug symfile off|on
519 Control display of debugging info regarding reading symbol files and
520 symbol tables within those files
522 set print raw frame-arguments
523 show print raw frame-arguments
524 Set/show whether to print frame arguments in raw mode,
525 disregarding any defined pretty-printers.
527 set remote trace-status-packet
528 show remote trace-status-packet
529 Set/show the use of remote protocol qTStatus packet.
533 Control display of debugging messages related to Nios II targets.
537 Control whether target-assisted range stepping is enabled.
539 set startup-with-shell
540 show startup-with-shell
541 Specifies whether Unix child processes are started via a shell or
546 Use the target memory cache for accesses to the code segment. This
547 improves performance of remote debugging (particularly disassembly).
549 * You can now use a literal value 'unlimited' for options that
550 interpret 0 or -1 as meaning "unlimited". E.g., "set
551 trace-buffer-size unlimited" is now an alias for "set
552 trace-buffer-size -1" and "set height unlimited" is now an alias for
555 * The "set debug symtab-create" debugging option of GDB has been changed to
556 accept a verbosity level. 0 means "off", 1 provides basic debugging
557 output, and values of 2 or greater provides more verbose output.
559 * New command-line options
561 Display the details of GDB configure-time options.
563 * The command 'tsave' can now support new option '-ctf' to save trace
564 buffer in Common Trace Format.
566 * Newly installed $prefix/bin/gcore acts as a shell interface for the
569 * GDB now implements the the C++ 'typeid' operator.
571 * The new convenience variable $_exception holds the exception being
572 thrown or caught at an exception-related catchpoint.
574 * The exception-related catchpoints, like "catch throw", now accept a
575 regular expression which can be used to filter exceptions by type.
577 * The new convenience variable $_exitsignal is automatically set to
578 the terminating signal number when the program being debugged dies
579 due to an uncaught signal.
583 ** All MI commands now accept an optional "--language" option.
584 Support for this feature can be verified by using the "-list-features"
585 command, which should contain "language-option".
587 ** The new command -info-gdb-mi-command allows the user to determine
588 whether a GDB/MI command is supported or not.
590 ** The "^error" result record returned when trying to execute an undefined
591 GDB/MI command now provides a variable named "code" whose content is the
592 "undefined-command" error code. Support for this feature can be verified
593 by using the "-list-features" command, which should contain
594 "undefined-command-error-code".
596 ** The -trace-save MI command can optionally save trace buffer in Common
599 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
601 ** The command -data-list-register-values now accepts an optional
602 "--skip-unavailable" option. When used, only the available registers
605 ** The new command -trace-frame-collected dumps collected variables,
606 computed expressions, tvars, memory and registers in a traceframe.
608 ** The commands -stack-list-locals, -stack-list-arguments and
609 -stack-list-variables now accept an option "--skip-unavailable".
610 When used, only the available locals or arguments are displayed.
612 ** The -exec-run command now accepts an optional "--start" option.
613 When used, the command follows the same semantics as the "start"
614 command, stopping the program's execution at the start of its
615 main subprogram. Support for this feature can be verified using
616 the "-list-features" command, which should contain
617 "exec-run-start-option".
619 ** The new commands -catch-assert and -catch-exceptions insert
620 catchpoints stopping the program when Ada exceptions are raised.
622 ** The new command -info-ada-exceptions provides the equivalent of
623 the new "info exceptions" command.
625 * New system-wide configuration scripts
626 A GDB installation now provides scripts suitable for use as system-wide
627 configuration scripts for the following systems:
631 * GDB now supports target-assigned range stepping with remote targets.
632 This improves the performance of stepping source lines by reducing
633 the number of control packets from/to GDB. See "New remote packets"
636 * GDB now understands the element 'tvar' in the XML traceframe info.
637 It has the id of the collected trace state variables.
639 * On S/390 targets that provide the transactional-execution feature,
640 the program interruption transaction diagnostic block (TDB) is now
641 represented as a number of additional "registers" in GDB.
647 The vCont packet supports a new 'r' action, that tells the remote
648 stub to step through an address range itself, without GDB
649 involvemement at each single-step.
651 qXfer:libraries-svr4:read's annex
652 The previously unused annex of the qXfer:libraries-svr4:read packet
653 is now used to support passing an argument list. The remote stub
654 reports support for this argument list to GDB's qSupported query.
655 The defined arguments are "start" and "prev", used to reduce work
656 necessary for library list updating, resulting in significant
659 * New features in the GDB remote stub, GDBserver
661 ** GDBserver now supports target-assisted range stepping. Currently
662 enabled on x86/x86_64 GNU/Linux targets.
664 ** GDBserver now adds element 'tvar' in the XML in the reply to
665 'qXfer:traceframe-info:read'. It has the id of the collected
666 trace state variables.
668 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
671 * New 'z' formatter for printing and examining memory, this displays the
672 value as hexadecimal zero padded on the left to the size of the type.
674 * GDB can now use Windows x64 unwinding data.
676 * The "set remotebaud" command has been replaced by "set serial baud".
677 Similarly, "show remotebaud" has been replaced by "show serial baud".
678 The "set remotebaud" and "show remotebaud" commands are still available
679 to provide backward compatibility with older versions of GDB.
681 *** Changes in GDB 7.6
683 * Target record has been renamed to record-full.
684 Record/replay is now enabled with the "record full" command.
685 This also affects settings that are associated with full record/replay
686 that have been moved from "set/show record" to "set/show record full":
688 set|show record full insn-number-max
689 set|show record full stop-at-limit
690 set|show record full memory-query
692 * A new record target "record-btrace" has been added. The new target
693 uses hardware support to record the control-flow of a process. It
694 does not support replaying the execution, but it implements the
695 below new commands for investigating the recorded execution log.
696 This new recording method can be enabled using:
700 The "record-btrace" target is only available on Intel Atom processors
701 and requires a Linux kernel 2.6.32 or later.
703 * Two new commands have been added for record/replay to give information
704 about the recorded execution without having to replay the execution.
705 The commands are only supported by "record btrace".
707 record instruction-history prints the execution history at
708 instruction granularity
710 record function-call-history prints the execution history at
713 * New native configurations
715 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
716 FreeBSD/powerpc powerpc*-*-freebsd
717 x86_64/Cygwin x86_64-*-cygwin*
718 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
722 ARM AArch64 aarch64*-*-elf
723 ARM AArch64 GNU/Linux aarch64*-*-linux
724 Lynx 178 PowerPC powerpc-*-lynx*178
725 x86_64/Cygwin x86_64-*-cygwin*
726 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
728 * If the configured location of system.gdbinit file (as given by the
729 --with-system-gdbinit option at configure time) is in the
730 data-directory (as specified by --with-gdb-datadir at configure
731 time) or in one of its subdirectories, then GDB will look for the
732 system-wide init file in the directory specified by the
733 --data-directory command-line option.
735 * New command line options:
737 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
738 other initialization files, unlike -nx which disables all of them.
740 * Removed command line options
742 -epoch This was used by the gdb mode in Epoch, an ancient fork of
745 * The 'ptype' and 'whatis' commands now accept an argument to control
748 * 'info proc' now works on some core files.
752 ** Vectors can be created with gdb.Type.vector.
754 ** Python's atexit.register now works in GDB.
756 ** Types can be pretty-printed via a Python API.
758 ** Python 3 is now supported (in addition to Python 2.4 or later)
760 ** New class gdb.Architecture exposes GDB's internal representation
761 of architecture in the Python API.
763 ** New method Frame.architecture returns the gdb.Architecture object
764 corresponding to the frame's architecture.
766 * New Python-based convenience functions:
768 ** $_memeq(buf1, buf2, length)
769 ** $_streq(str1, str2)
771 ** $_regex(str, regex)
773 * The 'cd' command now defaults to using '~' (the home directory) if not
776 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
777 default for GCC since November 2000.
779 * The command 'forward-search' can now be abbreviated as 'fo'.
781 * The command 'info tracepoints' can now display 'installed on target'
782 or 'not installed on target' for each non-pending location of tracepoint.
784 * New configure options
786 --enable-libmcheck/--disable-libmcheck
787 By default, development versions are built with -lmcheck on hosts
788 that support it, in order to help track memory corruption issues.
789 Release versions, on the other hand, are built without -lmcheck
790 by default. The --enable-libmcheck/--disable-libmcheck configure
791 options allow the user to override that default.
792 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
793 This configure option allows the user to build GDB with
794 libbabeltrace using which GDB can read Common Trace Format data.
796 * New commands (for set/show, see "New options" below)
799 Catch signals. This is similar to "handle", but allows commands and
800 conditions to be attached.
803 List the BFDs known to GDB.
805 python-interactive [command]
807 Start a Python interactive prompt, or evaluate the optional command
808 and print the result of expressions.
811 "py" is a new alias for "python".
813 enable type-printer [name]...
814 disable type-printer [name]...
815 Enable or disable type printers.
819 ** For the Renesas Super-H architecture, the "regs" command has been removed
820 (has been deprecated in GDB 7.5), and "info all-registers" should be used
825 set print type methods (on|off)
826 show print type methods
827 Control whether method declarations are displayed by "ptype".
828 The default is to show them.
830 set print type typedefs (on|off)
831 show print type typedefs
832 Control whether typedef definitions are displayed by "ptype".
833 The default is to show them.
835 set filename-display basename|relative|absolute
836 show filename-display
837 Control the way in which filenames is displayed.
838 The default is "relative", which preserves previous behavior.
840 set trace-buffer-size
841 show trace-buffer-size
842 Request target to change the size of trace buffer.
844 set remote trace-buffer-size-packet auto|on|off
845 show remote trace-buffer-size-packet
846 Control the use of the remote protocol `QTBuffer:size' packet.
850 Control display of debugging messages related to ARM AArch64.
853 set debug coff-pe-read
854 show debug coff-pe-read
855 Control display of debugging messages related to reading of COFF/PE
860 Control display of debugging messages related to Mach-O symbols
863 set debug notification
864 show debug notification
865 Control display of debugging info for async remote notification.
869 ** Command parameter changes are now notified using new async record
870 "=cmd-param-changed".
871 ** Trace frame changes caused by command "tfind" are now notified using
872 new async record "=traceframe-changed".
873 ** The creation, deletion and modification of trace state variables
874 are now notified using new async records "=tsv-created",
875 "=tsv-deleted" and "=tsv-modified".
876 ** The start and stop of process record are now notified using new
877 async record "=record-started" and "=record-stopped".
878 ** Memory changes are now notified using new async record
880 ** The data-disassemble command response will include a "fullname" field
881 containing the absolute file name when source has been requested.
882 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
883 command, to allow pattern filling of memory areas.
884 ** New commands "-catch-load"/"-catch-unload" added for intercepting
885 library load/unload events.
886 ** The response to breakpoint commands and breakpoint async records
887 includes an "installed" field containing a boolean state about each
888 non-pending tracepoint location is whether installed on target or not.
889 ** Output of the "-trace-status" command includes a "trace-file" field
890 containing the name of the trace file being examined. This field is
891 optional, and only present when examining a trace file.
892 ** The "fullname" field is now always present along with the "file" field,
893 even if the file cannot be found by GDB.
895 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
896 You must have the LZMA library available when configuring GDB for this
897 feature to be enabled. For more information, see:
898 http://fedoraproject.org/wiki/Features/MiniDebugInfo
903 Set the size of trace buffer. The remote stub reports support for this
904 packet to gdb's qSupported query.
907 Enable Branch Trace Store (BTS)-based branch tracing for the current
908 thread. The remote stub reports support for this packet to gdb's
912 Disable branch tracing for the current thread. The remote stub reports
913 support for this packet to gdb's qSupported query.
916 Read the traced branches for the current thread. The remote stub
917 reports support for this packet to gdb's qSupported query.
919 *** Changes in GDB 7.5
921 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
922 for more x32 ABI info.
924 * GDB now supports access to MIPS DSP registers on Linux targets.
926 * GDB now supports debugging microMIPS binaries.
928 * The "info os" command on GNU/Linux can now display information on
929 several new classes of objects managed by the operating system:
930 "info os procgroups" lists process groups
931 "info os files" lists file descriptors
932 "info os sockets" lists internet-domain sockets
933 "info os shm" lists shared-memory regions
934 "info os semaphores" lists semaphores
935 "info os msg" lists message queues
936 "info os modules" lists loaded kernel modules
938 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
939 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
940 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
941 options and inspect the probe arguments using the new $_probe_arg family
942 of convenience variables. You can obtain more information about SystemTap
943 in <http://sourceware.org/systemtap/>.
945 * GDB now supports reversible debugging on ARM, it allows you to
946 debug basic ARM and THUMB instructions, and provides
947 record/replay support.
949 * The option "symbol-reloading" has been deleted as it is no longer used.
953 ** GDB commands implemented in Python can now be put in command class
956 ** The "maint set python print-stack on|off" is now deleted.
958 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
959 apply "flag enum"-style pretty-printing to any enum.
961 ** gdb.lookup_symbol can now work when there is no current frame.
963 ** gdb.Symbol now has a 'line' attribute, holding the line number in
964 the source at which the symbol was defined.
966 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
967 method 'value'. The former indicates whether the symbol needs a
968 frame in order to compute its value, and the latter computes the
971 ** A new method 'referenced_value' on gdb.Value objects which can
972 dereference pointer as well as C++ reference values.
974 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
975 which return the global and static blocks (as gdb.Block objects),
976 of the underlying symbol table, respectively.
978 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
979 object associated with a PC value.
981 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
982 of the address range occupied by code for the current source line.
984 * Go language support.
985 GDB now supports debugging programs written in the Go programming
988 * GDBserver now supports stdio connections.
989 E.g. (gdb) target remote | ssh myhost gdbserver - hello
991 * The binary "gdbtui" can no longer be built or installed.
992 Use "gdb -tui" instead.
994 * GDB will now print "flag" enums specially. A flag enum is one where
995 all the enumerator values have no bits in common when pairwise
996 "and"ed. When printing a value whose type is a flag enum, GDB will
997 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
998 (gdb) print (enum E) 3
1001 * The filename part of a linespec will now match trailing components
1002 of a source file name. For example, "break gcc/expr.c:1000" will
1003 now set a breakpoint in build/gcc/expr.c, but not
1004 build/libcpp/expr.c.
1006 * The "info proc" and "generate-core-file" commands will now also
1007 work on remote targets connected to GDBserver on Linux.
1009 * The command "info catch" has been removed. It has been disabled
1010 since December 2007.
1012 * The "catch exception" and "catch assert" commands now accept
1013 a condition at the end of the command, much like the "break"
1014 command does. For instance:
1016 (gdb) catch exception Constraint_Error if Barrier = True
1018 Previously, it was possible to add a condition to such catchpoints,
1019 but it had to be done as a second step, after the catchpoint had been
1020 created, using the "condition" command.
1022 * The "info static-tracepoint-marker" command will now also work on
1023 native Linux targets with in-process agent.
1025 * GDB can now set breakpoints on inlined functions.
1027 * The .gdb_index section has been updated to include symbols for
1028 inlined functions. GDB will ignore older .gdb_index sections by
1029 default, which could cause symbol files to be loaded more slowly
1030 until their .gdb_index sections can be recreated. The new command
1031 "set use-deprecated-index-sections on" will cause GDB to use any older
1032 .gdb_index sections it finds. This will restore performance, but the
1033 ability to set breakpoints on inlined functions will be lost in symbol
1034 files with older .gdb_index sections.
1036 The .gdb_index section has also been updated to record more information
1037 about each symbol. This speeds up the "info variables", "info functions"
1038 and "info types" commands when used with programs having the .gdb_index
1039 section, as well as speeding up debugging with shared libraries using
1040 the .gdb_index section.
1042 * Ada support for GDB/MI Variable Objects has been added.
1044 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1049 ** New command -info-os is the MI equivalent of "info os".
1051 ** Output logs ("set logging" and related) now include MI output.
1055 ** "set use-deprecated-index-sections on|off"
1056 "show use-deprecated-index-sections on|off"
1057 Controls the use of deprecated .gdb_index sections.
1059 ** "catch load" and "catch unload" can be used to stop when a shared
1060 library is loaded or unloaded, respectively.
1062 ** "enable count" can be used to auto-disable a breakpoint after
1065 ** "info vtbl" can be used to show the virtual method tables for
1066 C++ and Java objects.
1068 ** "explore" and its sub commands "explore value" and "explore type"
1069 can be used to recursively explore values and types of
1070 expressions. These commands are available only if GDB is
1071 configured with '--with-python'.
1073 ** "info auto-load" shows status of all kinds of auto-loaded files,
1074 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1075 sequences of commands files, "info auto-load python-scripts"
1076 shows status of auto-loading Python script files,
1077 "info auto-load local-gdbinit" shows status of loading init file
1078 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1079 status of inferior specific thread debugging shared library loading.
1081 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1082 and "show auto-load-scripts" commands have been deprecated, use their
1083 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1084 and "show auto-load python-scripts" counterparts instead.
1086 ** "dprintf location,format,args..." creates a dynamic printf, which
1087 is basically a breakpoint that does a printf and immediately
1088 resumes your program's execution, so it is like a printf that you
1089 can insert dynamically at runtime instead of at compiletime.
1091 ** "set print symbol"
1093 Controls whether GDB attempts to display the symbol, if any,
1094 corresponding to addresses it prints. This defaults to "on", but
1095 you can set it to "off" to restore GDB's previous behavior.
1097 * Deprecated commands
1099 ** For the Renesas Super-H architecture, the "regs" command has been
1100 deprecated, and "info all-registers" should be used instead.
1104 Renesas RL78 rl78-*-elf
1105 HP OpenVMS ia64 ia64-hp-openvms*
1107 * GDBserver supports evaluation of breakpoint conditions. When
1108 support is advertised by GDBserver, GDB may be told to send the
1109 breakpoint conditions in bytecode form to GDBserver. GDBserver
1110 will only report the breakpoint trigger to GDB when its condition
1115 set mips compression
1116 show mips compression
1117 Select the compressed ISA encoding used in functions that have no symbol
1118 information available. The encoding can be set to either of:
1121 and is updated automatically from ELF file flags if available.
1123 set breakpoint condition-evaluation
1124 show breakpoint condition-evaluation
1125 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1126 GDBserver ("target"). Default option "auto" chooses the most efficient
1128 This option can improve debugger efficiency depending on the speed of the
1132 Disable auto-loading globally.
1135 Show auto-loading setting of all kinds of auto-loaded files.
1137 set auto-load gdb-scripts on|off
1138 show auto-load gdb-scripts
1139 Control auto-loading of GDB canned sequences of commands files.
1141 set auto-load python-scripts on|off
1142 show auto-load python-scripts
1143 Control auto-loading of Python script files.
1145 set auto-load local-gdbinit on|off
1146 show auto-load local-gdbinit
1147 Control loading of init file (.gdbinit) from current directory.
1149 set auto-load libthread-db on|off
1150 show auto-load libthread-db
1151 Control auto-loading of inferior specific thread debugging shared library.
1153 set auto-load scripts-directory <dir1>[:<dir2>...]
1154 show auto-load scripts-directory
1155 Set a list of directories from which to load auto-loaded scripts.
1156 Automatically loaded Python scripts and GDB scripts are located in one
1157 of the directories listed by this option.
1158 The delimiter (':' above) may differ according to the host platform.
1160 set auto-load safe-path <dir1>[:<dir2>...]
1161 show auto-load safe-path
1162 Set a list of directories from which it is safe to auto-load files.
1163 The delimiter (':' above) may differ according to the host platform.
1165 set debug auto-load on|off
1166 show debug auto-load
1167 Control display of debugging info for auto-loading the files above.
1169 set dprintf-style gdb|call|agent
1171 Control the way in which a dynamic printf is performed; "gdb"
1172 requests a GDB printf command, while "call" causes dprintf to call a
1173 function in the inferior. "agent" requests that the target agent
1174 (such as GDBserver) do the printing.
1176 set dprintf-function <expr>
1177 show dprintf-function
1178 set dprintf-channel <expr>
1179 show dprintf-channel
1180 Set the function and optional first argument to the call when using
1181 the "call" style of dynamic printf.
1183 set disconnected-dprintf on|off
1184 show disconnected-dprintf
1185 Control whether agent-style dynamic printfs continue to be in effect
1186 after GDB disconnects.
1188 * New configure options
1190 --with-auto-load-dir
1191 Configure default value for the 'set auto-load scripts-directory'
1192 setting above. It defaults to '$debugdir:$datadir/auto-load',
1193 $debugdir representing global debugging info directories (available
1194 via 'show debug-file-directory') and $datadir representing GDB's data
1195 directory (available via 'show data-directory').
1197 --with-auto-load-safe-path
1198 Configure default value for the 'set auto-load safe-path' setting
1199 above. It defaults to the --with-auto-load-dir setting.
1201 --without-auto-load-safe-path
1202 Set 'set auto-load safe-path' to '/', effectively disabling this
1205 * New remote packets
1207 z0/z1 conditional breakpoints extension
1209 The z0/z1 breakpoint insertion packets have been extended to carry
1210 a list of conditional expressions over to the remote stub depending on the
1211 condition evaluation mode. The use of this extension can be controlled
1212 via the "set remote conditional-breakpoints-packet" command.
1216 Specify the signals which the remote stub may pass to the debugged
1217 program without GDB involvement.
1219 * New command line options
1221 --init-command=FILE, -ix Like --command, -x but execute it
1222 before loading inferior.
1223 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1224 execute it before loading inferior.
1226 *** Changes in GDB 7.4
1228 * GDB now handles ambiguous linespecs more consistently; the existing
1229 FILE:LINE support has been expanded to other types of linespecs. A
1230 breakpoint will now be set on all matching locations in all
1231 inferiors, and locations will be added or removed according to
1234 * GDB now allows you to skip uninteresting functions and files when
1235 stepping with the "skip function" and "skip file" commands.
1237 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1238 and "show remote hardware-watchpoint-length-limit". These allows to
1239 set or show the maximum length limit (in bytes) of a remote
1240 target hardware watchpoint.
1242 This allows e.g. to use "unlimited" hardware watchpoints with the
1243 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1244 watchpoints are slower than real hardware watchpoints but are
1245 significantly faster than gdb software watchpoints.
1249 ** The register_pretty_printer function in module gdb.printing now takes
1250 an optional `replace' argument. If True, the new printer replaces any
1253 ** The "maint set python print-stack on|off" command has been
1254 deprecated and will be deleted in GDB 7.5.
1255 A new command: "set python print-stack none|full|message" has
1256 replaced it. Additionally, the default for "print-stack" is
1257 now "message", which just prints the error message without
1260 ** A prompt substitution hook (prompt_hook) is now available to the
1263 ** A new Python module, gdb.prompt has been added to the GDB Python
1264 modules library. This module provides functionality for
1265 escape sequences in prompts (used by set/show
1266 extended-prompt). These escape sequences are replaced by their
1267 corresponding value.
1269 ** Python commands and convenience-functions located in
1270 'data-directory'/python/gdb/command and
1271 'data-directory'/python/gdb/function are now automatically loaded
1274 ** Blocks now provide four new attributes. global_block and
1275 static_block will return the global and static blocks
1276 respectively. is_static and is_global are boolean attributes
1277 that indicate if the block is one of those two types.
1279 ** Symbols now provide the "type" attribute, the type of the symbol.
1281 ** The "gdb.breakpoint" function has been deprecated in favor of
1284 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1285 of a function. This class is based on the "finish" command
1286 available in the CLI.
1288 ** Type objects for struct and union types now allow access to
1289 the fields using standard Python dictionary (mapping) methods.
1290 For example, "some_type['myfield']" now works, as does
1291 "some_type.items()".
1293 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1296 ** A new function, "deep_items" has been added to the gdb.types
1297 module in the GDB Python modules library. This function returns
1298 an iterator over the fields of a struct or union type. Unlike
1299 the standard Python "iteritems" method, it will recursively traverse
1300 any anonymous fields.
1304 ** "*stopped" events can report several new "reason"s, such as
1307 ** Breakpoint changes are now notified using new async records, like
1308 "=breakpoint-modified".
1310 ** New command -ada-task-info.
1312 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1313 $sdir specifies the default system locations of shared libraries.
1314 $pdir specifies the directory where the libpthread used by the application
1317 GDB no longer looks in $sdir and $pdir after it has searched the directories
1318 mentioned in libthread-db-search-path. If you want to search those
1319 directories, they must be specified in libthread-db-search-path.
1320 The default value of libthread-db-search-path on GNU/Linux and Solaris
1321 systems is now "$sdir:$pdir".
1323 $pdir is not supported by gdbserver, it is currently ignored.
1324 $sdir is supported by gdbserver.
1326 * New configure option --with-iconv-bin.
1327 When using the internationalization support like the one in the GNU C
1328 library, GDB will invoke the "iconv" program to get a list of supported
1329 character sets. If this program lives in a non-standard location, one can
1330 use this option to specify where to find it.
1332 * When natively debugging programs on PowerPC BookE processors running
1333 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1334 watchpoints, which specify a mask in addition to an address to watch.
1335 The mask specifies that some bits of an address (the bits which are
1336 reset in the mask) should be ignored when matching the address accessed
1337 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1338 section in the user manual for more details.
1340 * The new option --once causes GDBserver to stop listening for connections once
1341 the first connection is made. The listening port used by GDBserver will
1342 become available after that.
1344 * New commands "info macros" and "alias" have been added.
1346 * New function parameters suffix @entry specifies value of function parameter
1347 at the time the function got called. Entry values are available only since
1353 "!" is now an alias of the "shell" command.
1354 Note that no space is needed between "!" and SHELL COMMAND.
1358 watch EXPRESSION mask MASK_VALUE
1359 The watch command now supports the mask argument which allows creation
1360 of masked watchpoints, if the current architecture supports this feature.
1362 info auto-load-scripts [REGEXP]
1363 This command was formerly named "maintenance print section-scripts".
1364 It is now generally useful and is no longer a maintenance-only command.
1366 info macro [-all] [--] MACRO
1367 The info macro command has new options `-all' and `--'. The first for
1368 printing all definitions of a macro. The second for explicitly specifying
1369 the end of arguments and the beginning of the macro name in case the macro
1370 name starts with a hyphen.
1372 collect[/s] EXPRESSIONS
1373 The tracepoint collect command now takes an optional modifier "/s"
1374 that directs it to dereference pointer-to-character types and
1375 collect the bytes of memory up to a zero byte. The behavior is
1376 similar to what you see when you use the regular print command on a
1377 string. An optional integer following the "/s" sets a bound on the
1378 number of bytes that will be collected.
1381 The trace start command now interprets any supplied arguments as a
1382 note to be recorded with the trace run, with an effect similar to
1383 setting the variable trace-notes.
1386 The trace stop command now interprets any arguments as a note to be
1387 mentioned along with the tstatus report that the trace was stopped
1388 with a command. The effect is similar to setting the variable
1391 * Tracepoints can now be enabled and disabled at any time after a trace
1392 experiment has been started using the standard "enable" and "disable"
1393 commands. It is now possible to start a trace experiment with no enabled
1394 tracepoints; GDB will display a warning, but will allow the experiment to
1395 begin, assuming that tracepoints will be enabled as needed while the trace
1398 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1399 locations with 4-byte instructions, when they were previously
1400 limited to locations with instructions of 5 bytes or longer.
1404 set debug dwarf2-read
1405 show debug dwarf2-read
1406 Turns on or off display of debugging messages related to reading
1407 DWARF debug info. The default is off.
1409 set debug symtab-create
1410 show debug symtab-create
1411 Turns on or off display of debugging messages related to symbol table
1412 creation. The default is off.
1415 show extended-prompt
1416 Set the GDB prompt, and allow escape sequences to be inserted to
1417 display miscellaneous information (see 'help set extended-prompt'
1418 for the list of sequences). This prompt (and any information
1419 accessed through the escape sequences) is updated every time the
1420 prompt is displayed.
1422 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1423 show print entry-values
1424 Set printing of frame argument values at function entry. In some cases
1425 GDB can determine the value of function argument which was passed by the
1426 function caller, even if the value was modified inside the called function.
1428 set debug entry-values
1429 show debug entry-values
1430 Control display of debugging info for determining frame argument values at
1431 function entry and virtual tail call frames.
1433 set basenames-may-differ
1434 show basenames-may-differ
1435 Set whether a source file may have multiple base names.
1436 (A "base name" is the name of a file with the directory part removed.
1437 Example: The base name of "/home/user/hello.c" is "hello.c".)
1438 If set, GDB will canonicalize file names (e.g., expand symlinks)
1439 before comparing them. Canonicalization is an expensive operation,
1440 but it allows the same file be known by more than one base name.
1441 If not set (the default), all source files are assumed to have just
1442 one base name, and gdb will do file name comparisons more efficiently.
1448 Set a user name and notes for the current and any future trace runs.
1449 This is useful for long-running and/or disconnected traces, to
1450 inform others (or yourself) as to who is running the trace, supply
1451 contact information, or otherwise explain what is going on.
1453 set trace-stop-notes
1454 show trace-stop-notes
1455 Set a note attached to the trace run, that is displayed when the
1456 trace has been stopped by a tstop command. This is useful for
1457 instance as an explanation, if you are stopping a trace run that was
1458 started by someone else.
1460 * New remote packets
1464 Dynamically enable a tracepoint in a started trace experiment.
1468 Dynamically disable a tracepoint in a started trace experiment.
1472 Set the user and notes of the trace run.
1476 Query the current status of a tracepoint.
1480 Query the minimum length of instruction at which a fast tracepoint may
1483 * Dcache size (number of lines) and line-size are now runtime-configurable
1484 via "set dcache line" and "set dcache line-size" commands.
1488 Texas Instruments TMS320C6x tic6x-*-*
1492 Renesas RL78 rl78-*-elf
1494 *** Changes in GDB 7.3.1
1496 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1498 *** Changes in GDB 7.3
1500 * GDB has a new command: "thread find [REGEXP]".
1501 It finds the thread id whose name, target id, or thread extra info
1502 matches the given regular expression.
1504 * The "catch syscall" command now works on mips*-linux* targets.
1506 * The -data-disassemble MI command now supports modes 2 and 3 for
1507 dumping the instruction opcodes.
1509 * New command line options
1511 -data-directory DIR Specify DIR as the "data-directory".
1512 This is mostly for testing purposes.
1514 * The "maint set python auto-load on|off" command has been renamed to
1515 "set auto-load-scripts on|off".
1517 * GDB has a new command: "set directories".
1518 It is like the "dir" command except that it replaces the
1519 source path list instead of augmenting it.
1521 * GDB now understands thread names.
1523 On GNU/Linux, "info threads" will display the thread name as set by
1524 prctl or pthread_setname_np.
1526 There is also a new command, "thread name", which can be used to
1527 assign a name internally for GDB to display.
1530 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1531 has been integrated into GDB.
1535 ** The function gdb.Write now accepts an optional keyword 'stream'.
1536 This keyword, when provided, will direct the output to either
1537 stdout, stderr, or GDB's logging output.
1539 ** Parameters can now be be sub-classed in Python, and in particular
1540 you may implement the get_set_doc and get_show_doc functions.
1541 This improves how Parameter set/show documentation is processed
1542 and allows for more dynamic content.
1544 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1545 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1546 have an is_valid method.
1548 ** Breakpoints can now be sub-classed in Python, and in particular
1549 you may implement a 'stop' function that is executed each time
1550 the inferior reaches that breakpoint.
1552 ** New function gdb.lookup_global_symbol looks up a global symbol.
1554 ** GDB values in Python are now callable if the value represents a
1555 function. For example, if 'some_value' represents a function that
1556 takes two integer parameters and returns a value, you can call
1557 that function like so:
1559 result = some_value (10,20)
1561 ** Module gdb.types has been added.
1562 It contains a collection of utilities for working with gdb.Types objects:
1563 get_basic_type, has_field, make_enum_dict.
1565 ** Module gdb.printing has been added.
1566 It contains utilities for writing and registering pretty-printers.
1567 New classes: PrettyPrinter, SubPrettyPrinter,
1568 RegexpCollectionPrettyPrinter.
1569 New function: register_pretty_printer.
1571 ** New commands "info pretty-printers", "enable pretty-printer" and
1572 "disable pretty-printer" have been added.
1574 ** gdb.parameter("directories") is now available.
1576 ** New function gdb.newest_frame returns the newest frame in the
1579 ** The gdb.InferiorThread class has a new "name" attribute. This
1580 holds the thread's name.
1582 ** Python Support for Inferior events.
1583 Python scripts can add observers to be notified of events
1584 occurring in the process being debugged.
1585 The following events are currently supported:
1586 - gdb.events.cont Continue event.
1587 - gdb.events.exited Inferior exited event.
1588 - gdb.events.stop Signal received, and Breakpoint hit events.
1592 ** GDB now puts template parameters in scope when debugging in an
1593 instantiation. For example, if you have:
1595 template<int X> int func (void) { return X; }
1597 then if you step into func<5>, "print X" will show "5". This
1598 feature requires proper debuginfo support from the compiler; it
1599 was added to GCC 4.5.
1601 ** The motion commands "next", "finish", "until", and "advance" now
1602 work better when exceptions are thrown. In particular, GDB will
1603 no longer lose control of the inferior; instead, the GDB will
1604 stop the inferior at the point at which the exception is caught.
1605 This functionality requires a change in the exception handling
1606 code that was introduced in GCC 4.5.
1608 * GDB now follows GCC's rules on accessing volatile objects when
1609 reading or writing target state during expression evaluation.
1610 One notable difference to prior behavior is that "print x = 0"
1611 no longer generates a read of x; the value of the assignment is
1612 now always taken directly from the value being assigned.
1614 * GDB now has some support for using labels in the program's source in
1615 linespecs. For instance, you can use "advance label" to continue
1616 execution to a label.
1618 * GDB now has support for reading and writing a new .gdb_index
1619 section. This section holds a fast index of DWARF debugging
1620 information and can be used to greatly speed up GDB startup and
1621 operation. See the documentation for `save gdb-index' for details.
1623 * The "watch" command now accepts an optional "-location" argument.
1624 When used, this causes GDB to watch the memory referred to by the
1625 expression. Such a watchpoint is never deleted due to it going out
1628 * GDB now supports thread debugging of core dumps on GNU/Linux.
1630 GDB now activates thread debugging using the libthread_db library
1631 when debugging GNU/Linux core dumps, similarly to when debugging
1632 live processes. As a result, when debugging a core dump file, GDB
1633 is now able to display pthread_t ids of threads. For example, "info
1634 threads" shows the same output as when debugging the process when it
1635 was live. In earlier releases, you'd see something like this:
1638 * 1 LWP 6780 main () at main.c:10
1640 While now you see this:
1643 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1645 It is also now possible to inspect TLS variables when debugging core
1648 When debugging a core dump generated on a machine other than the one
1649 used to run GDB, you may need to point GDB at the correct
1650 libthread_db library with the "set libthread-db-search-path"
1651 command. See the user manual for more details on this command.
1653 * When natively debugging programs on PowerPC BookE processors running
1654 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1655 which stop execution of the inferior whenever it executes an instruction
1656 at any address within the specified range. See the "PowerPC Embedded"
1657 section in the user manual for more details.
1659 * New features in the GDB remote stub, GDBserver
1661 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1662 and i686 LynxOS (version 5.x).
1664 ** GDBserver is now supported on Blackfin Linux.
1666 * New native configurations
1668 ia64 HP-UX ia64-*-hpux*
1672 Analog Devices, Inc. Blackfin Processor bfin-*
1674 * Ada task switching is now supported on sparc-elf targets when
1675 debugging a program using the Ravenscar Profile. For more information,
1676 see the "Tasking Support when using the Ravenscar Profile" section
1677 in the GDB user manual.
1679 * Guile support was removed.
1681 * New features in the GNU simulator
1683 ** The --map-info flag lists all known core mappings.
1685 ** CFI flashes may be simulated via the "cfi" device.
1687 *** Changes in GDB 7.2
1689 * Shared library support for remote targets by default
1691 When GDB is configured for a generic, non-OS specific target, like
1692 for example, --target=arm-eabi or one of the many *-*-elf targets,
1693 GDB now queries remote stubs for loaded shared libraries using the
1694 `qXfer:libraries:read' packet. Previously, shared library support
1695 was always disabled for such configurations.
1699 ** Argument Dependent Lookup (ADL)
1701 In C++ ADL lookup directs function search to the namespaces of its
1702 arguments even if the namespace has not been imported.
1712 Here the compiler will search for `foo' in the namespace of 'b'
1713 and find A::foo. GDB now supports this. This construct is commonly
1714 used in the Standard Template Library for operators.
1716 ** Improved User Defined Operator Support
1718 In addition to member operators, GDB now supports lookup of operators
1719 defined in a namespace and imported with a `using' directive, operators
1720 defined in the global scope, operators imported implicitly from an
1721 anonymous namespace, and the ADL operators mentioned in the previous
1723 GDB now also supports proper overload resolution for all the previously
1724 mentioned flavors of operators.
1726 ** static const class members
1728 Printing of static const class members that are initialized in the
1729 class definition has been fixed.
1731 * Windows Thread Information Block access.
1733 On Windows targets, GDB now supports displaying the Windows Thread
1734 Information Block (TIB) structure. This structure is visible either
1735 by using the new command `info w32 thread-information-block' or, by
1736 dereferencing the new convenience variable named `$_tlb', a
1737 thread-specific pointer to the TIB. This feature is also supported
1738 when remote debugging using GDBserver.
1740 * Static tracepoints
1742 Static tracepoints are calls in the user program into a tracing
1743 library. One such library is a port of the LTTng kernel tracer to
1744 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1745 When debugging with GDBserver, GDB now supports combining the GDB
1746 tracepoint machinery with such libraries. For example: the user can
1747 use GDB to probe a static tracepoint marker (a call from the user
1748 program into the tracing library) with the new "strace" command (see
1749 "New commands" below). This creates a "static tracepoint" in the
1750 breakpoint list, that can be manipulated with the same feature set
1751 as fast and regular tracepoints. E.g., collect registers, local and
1752 global variables, collect trace state variables, and define
1753 tracepoint conditions. In addition, the user can collect extra
1754 static tracepoint marker specific data, by collecting the new
1755 $_sdata internal variable. When analyzing the trace buffer, you can
1756 inspect $_sdata like any other variable available to GDB. For more
1757 information, see the "Tracepoints" chapter in GDB user manual. New
1758 remote packets have been defined to support static tracepoints, see
1759 the "New remote packets" section below.
1761 * Better reconstruction of tracepoints after disconnected tracing
1763 GDB will attempt to download the original source form of tracepoint
1764 definitions when starting a trace run, and then will upload these
1765 upon reconnection to the target, resulting in a more accurate
1766 reconstruction of the tracepoints that are in use on the target.
1770 You can now exercise direct control over the ways that GDB can
1771 affect your program. For instance, you can disallow the setting of
1772 breakpoints, so that the program can run continuously (assuming
1773 non-stop mode). In addition, the "observer" variable is available
1774 to switch all of the different controls; in observer mode, GDB
1775 cannot affect the target's behavior at all, which is useful for
1776 tasks like diagnosing live systems in the field.
1778 * The new convenience variable $_thread holds the number of the
1781 * New remote packets
1785 Return the address of the Windows Thread Information Block of a given thread.
1789 In response to several of the tracepoint packets, the target may now
1790 also respond with a number of intermediate `qRelocInsn' request
1791 packets before the final result packet, to have GDB handle
1792 relocating an instruction to execute at a different address. This
1793 is particularly useful for stubs that support fast tracepoints. GDB
1794 reports support for this feature in the qSupported packet.
1798 List static tracepoint markers in the target program.
1802 List static tracepoint markers at a given address in the target
1805 qXfer:statictrace:read
1807 Read the static trace data collected (by a `collect $_sdata'
1808 tracepoint action). The remote stub reports support for this packet
1809 to gdb's qSupported query.
1813 Send the current settings of GDB's permission flags.
1817 Send part of the source (textual) form of a tracepoint definition,
1818 which includes location, conditional, and action list.
1820 * The source command now accepts a -s option to force searching for the
1821 script in the source search path even if the script name specifies
1824 * New features in the GDB remote stub, GDBserver
1826 - GDBserver now support tracepoints (including fast tracepoints, and
1827 static tracepoints). The feature is currently supported by the
1828 i386-linux and amd64-linux builds. See the "Tracepoints support
1829 in gdbserver" section in the manual for more information.
1831 GDBserver JIT compiles the tracepoint's conditional agent
1832 expression bytecode into native code whenever possible for low
1833 overhead dynamic tracepoints conditionals. For such tracepoints,
1834 an expression that examines program state is evaluated when the
1835 tracepoint is reached, in order to determine whether to capture
1836 trace data. If the condition is simple and false, processing the
1837 tracepoint finishes very quickly and no data is gathered.
1839 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1840 for static tracepoints support.
1842 - GDBserver now supports x86_64 Windows 64-bit debugging.
1844 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1845 it understands register description.
1847 * The --batch flag now disables pagination and queries.
1849 * X86 general purpose registers
1851 GDB now supports reading/writing byte, word and double-word x86
1852 general purpose registers directly. This means you can use, say,
1853 $ah or $ax to refer, respectively, to the byte register AH and
1854 16-bit word register AX that are actually portions of the 32-bit
1855 register EAX or 64-bit register RAX.
1857 * The `commands' command now accepts a range of breakpoints to modify.
1858 A plain `commands' following a command that creates multiple
1859 breakpoints affects all the breakpoints set by that command. This
1860 applies to breakpoints set by `rbreak', and also applies when a
1861 single `break' command creates multiple breakpoints (e.g.,
1862 breakpoints on overloaded c++ functions).
1864 * The `rbreak' command now accepts a filename specification as part of
1865 its argument, limiting the functions selected by the regex to those
1866 in the specified file.
1868 * Support for remote debugging Windows and SymbianOS shared libraries
1869 from Unix hosts has been improved. Non Windows GDB builds now can
1870 understand target reported file names that follow MS-DOS based file
1871 system semantics, such as file names that include drive letters and
1872 use the backslash character as directory separator. This makes it
1873 possible to transparently use the "set sysroot" and "set
1874 solib-search-path" on Unix hosts to point as host copies of the
1875 target's shared libraries. See the new command "set
1876 target-file-system-kind" described below, and the "Commands to
1877 specify files" section in the user manual for more information.
1881 eval template, expressions...
1882 Convert the values of one or more expressions under the control
1883 of the string template to a command line, and call it.
1885 set target-file-system-kind unix|dos-based|auto
1886 show target-file-system-kind
1887 Set or show the assumed file system kind for target reported file
1890 save breakpoints <filename>
1891 Save all current breakpoint definitions to a file suitable for use
1892 in a later debugging session. To read the saved breakpoint
1893 definitions, use the `source' command.
1895 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1898 info static-tracepoint-markers
1899 Display information about static tracepoint markers in the target.
1901 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1902 Define a static tracepoint by probing a marker at the given
1903 function, line, address, or marker ID.
1907 Enable and disable observer mode.
1909 set may-write-registers on|off
1910 set may-write-memory on|off
1911 set may-insert-breakpoints on|off
1912 set may-insert-tracepoints on|off
1913 set may-insert-fast-tracepoints on|off
1914 set may-interrupt on|off
1915 Set individual permissions for GDB effects on the target. Note that
1916 some of these settings can have undesirable or surprising
1917 consequences, particularly when changed in the middle of a session.
1918 For instance, disabling the writing of memory can prevent
1919 breakpoints from being inserted, cause single-stepping to fail, or
1920 even crash your program, if you disable after breakpoints have been
1921 inserted. However, GDB should not crash.
1923 set record memory-query on|off
1924 show record memory-query
1925 Control whether to stop the inferior if memory changes caused
1926 by an instruction cannot be recorded.
1931 The disassemble command now supports "start,+length" form of two arguments.
1935 ** GDB now provides a new directory location, called the python directory,
1936 where Python scripts written for GDB can be installed. The location
1937 of that directory is <data-directory>/python, where <data-directory>
1938 is the GDB data directory. For more details, see section `Scripting
1939 GDB using Python' in the manual.
1941 ** The GDB Python API now has access to breakpoints, symbols, symbol
1942 tables, program spaces, inferiors, threads and frame's code blocks.
1943 Additionally, GDB Parameters can now be created from the API, and
1944 manipulated via set/show in the CLI.
1946 ** New functions gdb.target_charset, gdb.target_wide_charset,
1947 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1949 ** New exception gdb.GdbError.
1951 ** Pretty-printers are now also looked up in the current program space.
1953 ** Pretty-printers can now be individually enabled and disabled.
1955 ** GDB now looks for names of Python scripts to auto-load in a
1956 special section named `.debug_gdb_scripts', in addition to looking
1957 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1959 * Tracepoint actions were unified with breakpoint commands. In particular,
1960 there are no longer differences in "info break" output for breakpoints and
1961 tracepoints and the "commands" command can be used for both tracepoints and
1962 regular breakpoints.
1966 ARM Symbian arm*-*-symbianelf*
1968 * D language support.
1969 GDB now supports debugging programs written in the D programming
1972 * GDB now supports the extended ptrace interface for PowerPC which is
1973 available since Linux kernel version 2.6.34. This automatically enables
1974 any hardware breakpoints and additional hardware watchpoints available in
1975 the processor. The old ptrace interface exposes just one hardware
1976 watchpoint and no hardware breakpoints.
1978 * GDB is now able to use the Data Value Compare (DVC) register available on
1979 embedded PowerPC processors to implement in hardware simple watchpoint
1980 conditions of the form:
1982 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1984 This works in native GDB running on Linux kernels with the extended ptrace
1985 interface mentioned above.
1987 *** Changes in GDB 7.1
1991 ** Namespace Support
1993 GDB now supports importing of namespaces in C++. This enables the
1994 user to inspect variables from imported namespaces. Support for
1995 namepace aliasing has also been added. So, if a namespace is
1996 aliased in the current scope (e.g. namepace C=A; ) the user can
1997 print variables using the alias (e.g. (gdb) print C::x).
2001 All known bugs relating to the printing of virtual base class were
2002 fixed. It is now possible to call overloaded static methods using a
2007 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2008 and reinterpret_cast<> are now handled by the C++ expression parser.
2012 Xilinx MicroBlaze microblaze-*-*
2017 Xilinx MicroBlaze microblaze
2020 * Multi-program debugging.
2022 GDB now has support for multi-program (a.k.a. multi-executable or
2023 multi-exec) debugging. This allows for debugging multiple inferiors
2024 simultaneously each running a different program under the same GDB
2025 session. See "Debugging Multiple Inferiors and Programs" in the
2026 manual for more information. This implied some user visible changes
2027 in the multi-inferior support. For example, "info inferiors" now
2028 lists inferiors that are not running yet or that have exited
2029 already. See also "New commands" and "New options" below.
2031 * New tracing features
2033 GDB's tracepoint facility now includes several new features:
2035 ** Trace state variables
2037 GDB tracepoints now include support for trace state variables, which
2038 are variables managed by the target agent during a tracing
2039 experiment. They are useful for tracepoints that trigger each
2040 other, so for instance one tracepoint can count hits in a variable,
2041 and then a second tracepoint has a condition that is true when the
2042 count reaches a particular value. Trace state variables share the
2043 $-syntax of GDB convenience variables, and can appear in both
2044 tracepoint actions and condition expressions. Use the "tvariable"
2045 command to create, and "info tvariables" to view; see "Trace State
2046 Variables" in the manual for more detail.
2050 GDB now includes an option for defining fast tracepoints, which
2051 targets may implement more efficiently, such as by installing a jump
2052 into the target agent rather than a trap instruction. The resulting
2053 speedup can be by two orders of magnitude or more, although the
2054 tradeoff is that some program locations on some target architectures
2055 might not allow fast tracepoint installation, for instance if the
2056 instruction to be replaced is shorter than the jump. To request a
2057 fast tracepoint, use the "ftrace" command, with syntax identical to
2058 the regular trace command.
2060 ** Disconnected tracing
2062 It is now possible to detach GDB from the target while it is running
2063 a trace experiment, then reconnect later to see how the experiment
2064 is going. In addition, a new variable disconnected-tracing lets you
2065 tell the target agent whether to continue running a trace if the
2066 connection is lost unexpectedly.
2070 GDB now has the ability to save the trace buffer into a file, and
2071 then use that file as a target, similarly to you can do with
2072 corefiles. You can select trace frames, print data that was
2073 collected in them, and use tstatus to display the state of the
2074 tracing run at the moment that it was saved. To create a trace
2075 file, use "tsave <filename>", and to use it, do "target tfile
2078 ** Circular trace buffer
2080 You can ask the target agent to handle the trace buffer as a
2081 circular buffer, discarding the oldest trace frames to make room for
2082 newer ones, by setting circular-trace-buffer to on. This feature may
2083 not be available for all target agents.
2088 The disassemble command, when invoked with two arguments, now requires
2089 the arguments to be comma-separated.
2092 The info variables command now displays variable definitions. Files
2093 which only declare a variable are not shown.
2096 The source command is now capable of sourcing Python scripts.
2097 This feature is dependent on the debugger being build with Python
2100 Related to this enhancement is also the introduction of a new command
2101 "set script-extension" (see below).
2103 * New commands (for set/show, see "New options" below)
2105 record save [<FILENAME>]
2106 Save a file (in core file format) containing the process record
2107 execution log for replay debugging at a later time.
2109 record restore <FILENAME>
2110 Restore the process record execution log that was saved at an
2111 earlier time, for replay debugging.
2113 add-inferior [-copies <N>] [-exec <FILENAME>]
2116 clone-inferior [-copies <N>] [ID]
2117 Make a new inferior ready to execute the same program another
2118 inferior has loaded.
2123 maint info program-spaces
2124 List the program spaces loaded into GDB.
2126 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2127 show remote interrupt-sequence
2128 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2129 as the sequence to the remote target in order to interrupt the execution.
2130 Ctrl-C is a default. Some system prefers BREAK which is high level of
2131 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2132 Magic SysRq g. It is BREAK signal and character 'g'.
2134 set remote interrupt-on-connect [on | off]
2135 show remote interrupt-on-connect
2136 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2137 remote target when gdb connects to it. This is needed when you debug
2140 set remotebreak [on | off]
2142 Deprecated. Use "set/show remote interrupt-sequence" instead.
2144 tvariable $NAME [ = EXP ]
2145 Create or modify a trace state variable.
2148 List trace state variables and their values.
2150 delete tvariable $NAME ...
2151 Delete one or more trace state variables.
2154 Evaluate the given expressions without collecting anything into the
2155 trace buffer. (Valid in tracepoint actions only.)
2157 ftrace FN / FILE:LINE / *ADDR
2158 Define a fast tracepoint at the given function, line, or address.
2160 * New expression syntax
2162 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2163 GDB now parses 0b101010 identically with 42.
2167 set follow-exec-mode new|same
2168 show follow-exec-mode
2169 Control whether GDB reuses the same inferior across an exec call or
2170 creates a new one. This is useful to be able to restart the old
2171 executable after the inferior having done an exec call.
2173 set default-collect EXPR, ...
2174 show default-collect
2175 Define a list of expressions to be collected at each tracepoint.
2176 This is a useful way to ensure essential items are not overlooked,
2177 such as registers or a critical global variable.
2179 set disconnected-tracing
2180 show disconnected-tracing
2181 If set to 1, the target is instructed to continue tracing if it
2182 loses its connection to GDB. If 0, the target is to stop tracing
2185 set circular-trace-buffer
2186 show circular-trace-buffer
2187 If set to on, the target is instructed to use a circular trace buffer
2188 and discard the oldest trace frames instead of stopping the trace due
2189 to a full trace buffer. If set to off, the trace stops when the buffer
2190 fills up. Some targets may not support this.
2192 set script-extension off|soft|strict
2193 show script-extension
2194 If set to "off", the debugger does not perform any script language
2195 recognition, and all sourced files are assumed to be GDB scripts.
2196 If set to "soft" (the default), files are sourced according to
2197 filename extension, falling back to GDB scripts if the first
2199 If set to "strict", files are sourced according to filename extension.
2201 set ada trust-PAD-over-XVS on|off
2202 show ada trust-PAD-over-XVS
2203 If off, activate a workaround against a bug in the debugging information
2204 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2205 the GCC sources for more information about the GNAT encoding and
2206 PAD types in particular). It is always safe to set this option to
2207 off, but this introduces a slight performance penalty. The default
2210 * Python API Improvements
2212 ** GDB provides the new class gdb.LazyString. This is useful in
2213 some pretty-printing cases. The new method gdb.Value.lazy_string
2214 provides a simple way to create objects of this type.
2216 ** The fields returned by gdb.Type.fields now have an
2217 `is_base_class' attribute.
2219 ** The new method gdb.Type.range returns the range of an array type.
2221 ** The new method gdb.parse_and_eval can be used to parse and
2222 evaluate an expression.
2224 * New remote packets
2227 Define a trace state variable.
2230 Get the current value of a trace state variable.
2233 Set desired tracing behavior upon disconnection.
2236 Set the trace buffer to be linear or circular.
2239 Get data about the tracepoints currently in use.
2243 Process record now works correctly with hardware watchpoints.
2245 Multiple bug fixes have been made to the mips-irix port, making it
2246 much more reliable. In particular:
2247 - Debugging threaded applications is now possible again. Previously,
2248 GDB would hang while starting the program, or while waiting for
2249 the program to stop at a breakpoint.
2250 - Attaching to a running process no longer hangs.
2251 - An error occurring while loading a core file has been fixed.
2252 - Changing the value of the PC register now works again. This fixes
2253 problems observed when using the "jump" command, or when calling
2254 a function from GDB, or even when assigning a new value to $pc.
2255 - With the "finish" and "return" commands, the return value for functions
2256 returning a small array is now correctly printed.
2257 - It is now possible to break on shared library code which gets executed
2258 during a shared library init phase (code executed while executing
2259 their .init section). Previously, the breakpoint would have no effect.
2260 - GDB is now able to backtrace through the signal handler for
2261 non-threaded programs.
2263 PIE (Position Independent Executable) programs debugging is now supported.
2264 This includes debugging execution of PIC (Position Independent Code) shared
2265 libraries although for that, it should be possible to run such libraries as an
2268 *** Changes in GDB 7.0
2270 * GDB now has an interface for JIT compilation. Applications that
2271 dynamically generate code can create symbol files in memory and register
2272 them with GDB. For users, the feature should work transparently, and
2273 for JIT developers, the interface is documented in the GDB manual in the
2274 "JIT Compilation Interface" chapter.
2276 * Tracepoints may now be conditional. The syntax is as for
2277 breakpoints; either an "if" clause appended to the "trace" command,
2278 or the "condition" command is available. GDB sends the condition to
2279 the target for evaluation using the same bytecode format as is used
2280 for tracepoint actions.
2282 * The disassemble command now supports: an optional /r modifier, print the
2283 raw instructions in hex as well as in symbolic form, and an optional /m
2284 modifier to print mixed source+assembly.
2286 * Process record and replay
2288 In a architecture environment that supports ``process record and
2289 replay'', ``process record and replay'' target can record a log of
2290 the process execution, and replay it with both forward and reverse
2293 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2294 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2295 set execution-direction {forward|reverse}, for targets that support
2298 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2299 feature is available with a native GDB running on kernel version
2302 * GDB now has support for multi-byte and wide character sets on the
2303 target. Strings whose character type is wchar_t, char16_t, or
2304 char32_t are now correctly printed. GDB supports wide- and unicode-
2305 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2306 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2307 `printf'. This feature requires iconv to work properly; if your
2308 system does not have a working iconv, GDB can use GNU libiconv. See
2309 the installation instructions for more information.
2311 * GDB now supports automatic retrieval of shared library files from
2312 remote targets. To use this feature, specify a system root that begins
2313 with the `remote:' prefix, either via the `set sysroot' command or via
2314 the `--with-sysroot' configure-time option.
2316 * "info sharedlibrary" now takes an optional regex of libraries to show,
2317 and it now reports if a shared library has no debugging information.
2319 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2320 now complete on file names.
2322 * When completing in expressions, gdb will attempt to limit
2323 completions to allowable structure or union fields, where appropriate.
2324 For instance, consider:
2326 # struct example { int f1; double f2; };
2327 # struct example variable;
2330 If the user types TAB at the end of this command line, the available
2331 completions will be "f1" and "f2".
2333 * Inlined functions are now supported. They show up in backtraces, and
2334 the "step", "next", and "finish" commands handle them automatically.
2336 * GDB now supports the token-splicing (##) and stringification (#)
2337 operators when expanding macros. It also supports variable-arity
2340 * GDB now supports inspecting extra signal information, exported by
2341 the new $_siginfo convenience variable. The feature is currently
2342 implemented on linux ARM, i386 and amd64.
2344 * GDB can now display the VFP floating point registers and NEON vector
2345 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2346 can provide these registers (requires Linux 2.6.30 or later). Remote
2347 and simulator targets may also provide them.
2349 * New remote packets
2352 Search memory for a sequence of bytes.
2355 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2356 operation over reliable transport links. Use of this packet is
2357 controlled by the `set remote noack-packet' command.
2360 Kill the process with the specified process ID. Use this in preference
2361 to `k' when multiprocess protocol extensions are supported.
2364 Obtains additional operating system information
2368 Read or write additional signal information.
2370 * Removed remote protocol undocumented extension
2372 An undocumented extension to the remote protocol's `S' stop reply
2373 packet that permited the stub to pass a process id was removed.
2374 Remote servers should use the `T' stop reply packet instead.
2376 * GDB now supports multiple function calling conventions according to the
2377 DWARF-2 DW_AT_calling_convention function attribute.
2379 * The SH target utilizes the aforementioned change to distinguish between gcc
2380 and Renesas calling convention. It also adds the new CLI commands
2381 `set/show sh calling-convention'.
2383 * GDB can now read compressed debug sections, as produced by GNU gold
2384 with the --compress-debug-sections=zlib flag.
2386 * 64-bit core files are now supported on AIX.
2388 * Thread switching is now supported on Tru64.
2390 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2391 which will be allocated using malloc later in program execution.
2393 * The qXfer:libraries:read remote procotol packet now allows passing a
2394 list of section offsets.
2396 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2397 conditions handling signals delivered during attach or thread creation
2398 have also been fixed.
2400 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2401 From the user's standpoint, all unqualified instances of True and False
2402 are treated as the standard definitions, regardless of context.
2404 * GDB now parses C++ symbol and type names more flexibly. For
2407 template<typename T> class C { };
2410 GDB will now correctly handle all of:
2412 ptype C<char const *>
2413 ptype C<char const*>
2414 ptype C<const char *>
2415 ptype C<const char*>
2417 * New features in the GDB remote stub, gdbserver
2419 - The "--wrapper" command-line argument tells gdbserver to use a
2420 wrapper program to launch programs for debugging.
2422 - On PowerPC and S/390 targets, it is now possible to use a single
2423 gdbserver executable to debug both 32-bit and 64-bit programs.
2424 (This requires gdbserver itself to be built as a 64-bit executable.)
2426 - gdbserver uses the new noack protocol mode for TCP connections to
2427 reduce communications latency, if also supported and enabled in GDB.
2429 - Support for the sparc64-linux-gnu target is now included in
2432 - The amd64-linux build of gdbserver now supports debugging both
2433 32-bit and 64-bit programs.
2435 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2436 now support hardware watchpoints, and will use them automatically
2441 GDB now has support for scripting using Python. Whether this is
2442 available is determined at configure time.
2444 New GDB commands can now be written in Python.
2446 * Ada tasking support
2448 Ada tasks can now be inspected in GDB. The following commands have
2452 Print the list of Ada tasks.
2454 Print detailed information about task number N.
2456 Print the task number of the current task.
2458 Switch the context of debugging to task number N.
2460 * Support for user-defined prefixed commands. The "define" command can
2461 add new commands to existing prefixes, e.g. "target".
2463 * Multi-inferior, multi-process debugging.
2465 GDB now has generalized support for multi-inferior debugging. See
2466 "Debugging Multiple Inferiors" in the manual for more information.
2467 Although availability still depends on target support, the command
2468 set is more uniform now. The GNU/Linux specific multi-forks support
2469 has been migrated to this new framework. This implied some user
2470 visible changes; see "New commands" and also "Removed commands"
2473 * Target descriptions can now describe the target OS ABI. See the
2474 "Target Description Format" section in the user manual for more
2477 * Target descriptions can now describe "compatible" architectures
2478 to indicate that the target can execute applications for a different
2479 architecture in addition to those for the main target architecture.
2480 See the "Target Description Format" section in the user manual for
2483 * Multi-architecture debugging.
2485 GDB now includes general supports for debugging applications on
2486 hybrid systems that use more than one single processor architecture
2487 at the same time. Each such hybrid architecture still requires
2488 specific support to be added. The only hybrid architecture supported
2489 in this version of GDB is the Cell Broadband Engine.
2491 * GDB now supports integrated debugging of Cell/B.E. applications that
2492 use both the PPU and SPU architectures. To enable support for hybrid
2493 Cell/B.E. debugging, you need to configure GDB to support both the
2494 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2495 --enable-targets configure option.
2497 * Non-stop mode debugging.
2499 For some targets, GDB now supports an optional mode of operation in
2500 which you can examine stopped threads while other threads continue
2501 to execute freely. This is referred to as non-stop mode, with the
2502 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2503 section in the user manual for more information.
2505 To be able to support remote non-stop debugging, a remote stub needs
2506 to implement the non-stop mode remote protocol extensions, as
2507 described in the "Remote Non-Stop" section of the user manual. The
2508 GDB remote stub, gdbserver, has been adjusted to support these
2509 extensions on linux targets.
2511 * New commands (for set/show, see "New options" below)
2513 catch syscall [NAME(S) | NUMBER(S)]
2514 Catch system calls. Arguments, which should be names of system
2515 calls or their numbers, mean catch only those syscalls. Without
2516 arguments, every syscall will be caught. When the inferior issues
2517 any of the specified syscalls, GDB will stop and announce the system
2518 call, both when it is called and when its call returns. This
2519 feature is currently available with a native GDB running on the
2520 Linux Kernel, under the following architectures: x86, x86_64,
2521 PowerPC and PowerPC64.
2523 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2525 Search memory for a sequence of bytes.
2527 maint set python print-stack
2528 maint show python print-stack
2529 Show a stack trace when an error is encountered in a Python script.
2532 Invoke CODE by passing it to the Python interpreter.
2537 These allow macros to be defined, undefined, and listed
2541 Show operating system information about processes.
2544 List the inferiors currently under GDB's control.
2547 Switch focus to inferior number NUM.
2550 Detach from inferior number NUM.
2553 Kill inferior number NUM.
2557 set spu stop-on-load
2558 show spu stop-on-load
2559 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2561 set spu auto-flush-cache
2562 show spu auto-flush-cache
2563 Control whether to automatically flush the software-managed cache
2564 during Cell/B.E. debugging.
2566 set sh calling-convention
2567 show sh calling-convention
2568 Control the calling convention used when calling SH target functions.
2571 show debug timestamp
2572 Control display of timestamps with GDB debugging output.
2574 set disassemble-next-line
2575 show disassemble-next-line
2576 Control display of disassembled source lines or instructions when
2579 set remote noack-packet
2580 show remote noack-packet
2581 Set/show the use of remote protocol QStartNoAckMode packet. See above
2582 under "New remote packets."
2584 set remote query-attached-packet
2585 show remote query-attached-packet
2586 Control use of remote protocol `qAttached' (query-attached) packet.
2588 set remote read-siginfo-object
2589 show remote read-siginfo-object
2590 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2593 set remote write-siginfo-object
2594 show remote write-siginfo-object
2595 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2598 set remote reverse-continue
2599 show remote reverse-continue
2600 Control use of remote protocol 'bc' (reverse-continue) packet.
2602 set remote reverse-step
2603 show remote reverse-step
2604 Control use of remote protocol 'bs' (reverse-step) packet.
2606 set displaced-stepping
2607 show displaced-stepping
2608 Control displaced stepping mode. Displaced stepping is a way to
2609 single-step over breakpoints without removing them from the debuggee.
2610 Also known as "out-of-line single-stepping".
2613 show debug displaced
2614 Control display of debugging info for displaced stepping.
2616 maint set internal-error
2617 maint show internal-error
2618 Control what GDB does when an internal error is detected.
2620 maint set internal-warning
2621 maint show internal-warning
2622 Control what GDB does when an internal warning is detected.
2627 Use a wrapper program to launch programs for debugging.
2629 set multiple-symbols (all|ask|cancel)
2630 show multiple-symbols
2631 The value of this variable can be changed to adjust the debugger behavior
2632 when an expression or a breakpoint location contains an ambiguous symbol
2633 name (an overloaded function name, for instance).
2635 set breakpoint always-inserted
2636 show breakpoint always-inserted
2637 Keep breakpoints always inserted in the target, as opposed to inserting
2638 them when resuming the target, and removing them when the target stops.
2639 This option can improve debugger performance on slow remote targets.
2641 set arm fallback-mode (arm|thumb|auto)
2642 show arm fallback-mode
2643 set arm force-mode (arm|thumb|auto)
2645 These commands control how ARM GDB determines whether instructions
2646 are ARM or Thumb. The default for both settings is auto, which uses
2647 the current CPSR value for instructions without symbols; previous
2648 versions of GDB behaved as if "set arm fallback-mode arm".
2650 set disable-randomization
2651 show disable-randomization
2652 Standalone programs run with the virtual address space randomization enabled
2653 by default on some platforms. This option keeps the addresses stable across
2654 multiple debugging sessions.
2658 Control whether other threads are stopped or not when some thread hits
2663 Requests that asynchronous execution is enabled in the target, if available.
2664 In this case, it's possible to resume target in the background, and interact
2665 with GDB while the target is running. "show target-async" displays the
2666 current state of asynchronous execution of the target.
2668 set target-wide-charset
2669 show target-wide-charset
2670 The target-wide-charset is the name of the character set that GDB
2671 uses when printing characters whose type is wchar_t.
2673 set tcp auto-retry (on|off)
2675 set tcp connect-timeout
2676 show tcp connect-timeout
2677 These commands allow GDB to retry failed TCP connections to a remote stub
2678 with a specified timeout period; this is useful if the stub is launched
2679 in parallel with GDB but may not be ready to accept connections immediately.
2681 set libthread-db-search-path
2682 show libthread-db-search-path
2683 Control list of directories which GDB will search for appropriate
2686 set schedule-multiple (on|off)
2687 show schedule-multiple
2688 Allow GDB to resume all threads of all processes or only threads of
2689 the current process.
2693 Use more aggressive caching for accesses to the stack. This improves
2694 performance of remote debugging (particularly backtraces) without
2695 affecting correctness.
2697 set interactive-mode (on|off|auto)
2698 show interactive-mode
2699 Control whether GDB runs in interactive mode (on) or not (off).
2700 When in interactive mode, GDB waits for the user to answer all
2701 queries. Otherwise, GDB does not wait and assumes the default
2702 answer. When set to auto (the default), GDB determines which
2703 mode to use based on the stdin settings.
2708 For program forks, this is replaced by the new more generic `info
2709 inferiors' command. To list checkpoints, you can still use the
2710 `info checkpoints' command, which was an alias for the `info forks'
2714 Replaced by the new `inferior' command. To switch between
2715 checkpoints, you can still use the `restart' command, which was an
2716 alias for the `fork' command.
2719 This is removed, since some targets don't have a notion of
2720 processes. To switch between processes, you can still use the
2721 `inferior' command using GDB's own inferior number.
2724 For program forks, this is replaced by the new more generic `kill
2725 inferior' command. To delete a checkpoint, you can still use the
2726 `delete checkpoint' command, which was an alias for the `delete
2730 For program forks, this is replaced by the new more generic `detach
2731 inferior' command. To detach a checkpoint, you can still use the
2732 `detach checkpoint' command, which was an alias for the `detach
2735 * New native configurations
2737 x86/x86_64 Darwin i[34567]86-*-darwin*
2739 x86_64 MinGW x86_64-*-mingw*
2743 Lattice Mico32 lm32-*
2744 x86 DICOS i[34567]86-*-dicos*
2745 x86_64 DICOS x86_64-*-dicos*
2748 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2749 (mingw32ce) debugging.
2755 These commands were actually not implemented on any target.
2757 *** Changes in GDB 6.8
2759 * New native configurations
2761 NetBSD/hppa hppa*-*netbsd*
2762 Xtensa GNU/Linux xtensa*-*-linux*
2766 NetBSD/hppa hppa*-*-netbsd*
2767 Xtensa GNU/Lunux xtensa*-*-linux*
2769 * Change in command line behavior -- corefiles vs. process ids.
2771 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2772 attaching to process NUMBER fails, GDB no longer attempts to open a
2773 core file named NUMBER. Attaching to a program using the -c option
2774 is no longer supported. Instead, use the '-p' or '--pid' options.
2776 * GDB can now be built as a native debugger for debugging Windows x86
2777 (mingw32) Portable Executable (PE) programs.
2779 * Pending breakpoints no longer change their number when their address
2782 * GDB now supports breakpoints with multiple locations,
2783 including breakpoints on C++ constructors, inside C++ templates,
2784 and in inlined functions.
2786 * GDB's ability to debug optimized code has been improved. GDB more
2787 accurately identifies function bodies and lexical blocks that occupy
2788 more than one contiguous range of addresses.
2790 * Target descriptions can now describe registers for PowerPC.
2792 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2793 registers on PowerPC targets.
2795 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2796 targets even when the libthread_db library is not available.
2798 * The GDB remote stub, gdbserver, now supports the new file transfer
2799 commands (remote put, remote get, and remote delete).
2801 * The GDB remote stub, gdbserver, now supports run and attach in
2802 extended-remote mode.
2804 * hppa*64*-*-hpux11* target broken
2805 The debugger is unable to start a program and fails with the following
2806 error: "Error trying to get information about dynamic linker".
2807 The gdb-6.7 release is also affected.
2809 * GDB now supports the --enable-targets= configure option to allow
2810 building a single GDB executable that supports multiple remote
2811 target architectures.
2813 * GDB now supports debugging C and C++ programs which use the
2814 Decimal Floating Point extension. In addition, the PowerPC target
2815 now has a set of pseudo-registers to inspect decimal float values
2816 stored in two consecutive float registers.
2818 * The -break-insert MI command can optionally create pending
2821 * Improved support for debugging Ada
2822 Many improvements to the Ada language support have been made. These
2824 - Better support for Ada2005 interface types
2825 - Improved handling of arrays and slices in general
2826 - Better support for Taft-amendment types
2827 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2829 - Improved command completion in Ada
2832 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2837 set print frame-arguments (all|scalars|none)
2838 show print frame-arguments
2839 The value of this variable can be changed to control which argument
2840 values should be printed by the debugger when displaying a frame.
2845 Transfer files to and from a remote target, and delete remote files.
2852 Transfer files to and from a remote target, and delete remote files.
2854 * New remote packets
2861 Open, close, read, write, and delete files on the remote system.
2864 Attach to an existing process on the remote system, in extended-remote
2868 Run a new process on the remote system, in extended-remote mode.
2870 *** Changes in GDB 6.7
2872 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2873 bfd, libiberty and opcodes, as revealed by static analysis donated by
2874 Coverity, Inc. (http://scan.coverity.com).
2876 * When looking up multiply-defined global symbols, GDB will now prefer the
2877 symbol definition in the current shared library if it was built using the
2878 -Bsymbolic linker option.
2880 * When the Text User Interface (TUI) is not configured, GDB will now
2881 recognize the -tui command-line option and print a message that the TUI
2884 * The GDB remote stub, gdbserver, now has lower overhead for high
2885 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2887 * GDB for MIPS targets now autodetects whether a remote target provides
2888 32-bit or 64-bit register values.
2890 * Support for C++ member pointers has been improved.
2892 * GDB now understands XML target descriptions, which specify the
2893 target's overall architecture. GDB can read a description from
2894 a local file or over the remote serial protocol.
2896 * Vectors of single-byte data use a new integer type which is not
2897 automatically displayed as character or string data.
2899 * The /s format now works with the print command. It displays
2900 arrays of single-byte integers and pointers to single-byte integers
2903 * Target descriptions can now describe target-specific registers,
2904 for architectures which have implemented the support (currently
2905 only ARM, M68K, and MIPS).
2907 * GDB and the GDB remote stub, gdbserver, now support the XScale
2910 * The GDB remote stub, gdbserver, has been updated to support
2911 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2912 has been rewritten to use the standard GDB remote protocol.
2914 * GDB can now step into C++ functions which are called through thunks.
2916 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2918 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2919 layout. It also supports a TextSeg= and DataSeg= response when only
2920 segment base addresses (rather than offsets) are available.
2922 * The /i format now outputs any trailing branch delay slot instructions
2923 immediately following the last instruction within the count specified.
2925 * The GDB remote protocol "T" stop reply packet now supports a
2926 "library" response. Combined with the new "qXfer:libraries:read"
2927 packet, this response allows GDB to debug shared libraries on targets
2928 where the operating system manages the list of loaded libraries (e.g.
2929 Windows and SymbianOS).
2931 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2932 (DLLs) on Windows and Windows CE targets.
2934 * GDB now supports a faster verification that a .debug file matches its binary
2935 according to its build-id signature, if the signature is present.
2941 Enable or disable hardware flow control (RTS/CTS) on the serial port
2942 when debugging using remote targets.
2944 set mem inaccessible-by-default
2945 show mem inaccessible-by-default
2946 If the target supplies a memory map, for instance via the remote
2947 protocol's "qXfer:memory-map:read" packet, setting this variable
2948 prevents GDB from accessing memory outside the memory map. This
2949 is useful for targets with memory mapped registers or which react
2950 badly to accesses of unmapped address space.
2952 set breakpoint auto-hw
2953 show breakpoint auto-hw
2954 If the target supplies a memory map, for instance via the remote
2955 protocol's "qXfer:memory-map:read" packet, setting this variable
2956 lets GDB use hardware breakpoints automatically for memory regions
2957 where it can not use software breakpoints. This covers both the
2958 "break" command and internal breakpoints used for other commands
2959 including "next" and "finish".
2962 catch exception unhandled
2963 Stop the program execution when Ada exceptions are raised.
2966 Stop the program execution when an Ada assertion failed.
2970 Set an alternate system root for target files. This is a more
2971 general version of "set solib-absolute-prefix", which is now
2972 an alias to "set sysroot".
2975 Provide extended SPU facility status information. This set of
2976 commands is available only when debugging the Cell/B.E. SPU
2979 * New native configurations
2981 OpenBSD/sh sh*-*openbsd*
2984 unset tdesc filename
2986 Use the specified local file as an XML target description, and do
2987 not query the target for its built-in description.
2991 OpenBSD/sh sh*-*-openbsd*
2992 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2993 Toshiba Media Processor mep-elf
2995 * New remote packets
2998 Ignore the specified signals; pass them directly to the debugged program
2999 without stopping other threads or reporting them to GDB.
3001 qXfer:features:read:
3002 Read an XML target description from the target, which describes its
3007 Read or write contents of an spufs file on the target system. These
3008 packets are available only on the Cell/B.E. SPU architecture.
3010 qXfer:libraries:read:
3011 Report the loaded shared libraries. Combined with new "T" packet
3012 response, this packet allows GDB to debug shared libraries on
3013 targets where the operating system manages the list of loaded
3014 libraries (e.g. Windows and SymbianOS).
3018 Support for these obsolete configurations has been removed.
3026 i[34567]86-*-lynxos*
3027 i[34567]86-*-netware*
3028 i[34567]86-*-sco3.2v5*
3029 i[34567]86-*-sco3.2v4*
3031 i[34567]86-*-sysv4.2*
3034 i[34567]86-*-unixware2*
3035 i[34567]86-*-unixware*
3044 * Other removed features
3051 Various m68k-only ROM monitors.
3058 Various Renesas ROM monitors and debugging interfaces for SH and
3063 Support for a Macraigor serial interface to on-chip debugging.
3064 GDB does not directly support the newer parallel or USB
3069 A debug information format. The predecessor to DWARF 2 and
3070 DWARF 3, which are still supported.
3072 Support for the HP aCC compiler on HP-UX/PA-RISC
3074 SOM-encapsulated symbolic debugging information, automatic
3075 invocation of pxdb, and the aCC custom C++ ABI. This does not
3076 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3077 with aCC can still be debugged on an assembly level.
3079 MIPS ".pdr" sections
3081 A MIPS-specific format used to describe stack frame layout
3082 in debugging information.
3086 GDB could work with an older version of Guile to debug
3087 the interpreter and Scheme programs running in it.
3089 set mips stack-arg-size
3090 set mips saved-gpreg-size
3092 Use "set mips abi" to control parameter passing for MIPS.
3094 *** Changes in GDB 6.6
3099 Cell Broadband Engine SPU spu-elf
3101 * GDB can now be configured as a cross-debugger targeting native Windows
3102 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3103 running on a Windows system over TCP/IP to debug Windows programs.
3105 * The GDB remote stub, gdbserver, has been updated to support Windows and
3106 Cygwin debugging. Both single-threaded and multi-threaded programs are
3109 * The "set trust-readonly-sections" command works again. This command was
3110 broken in GDB 6.3, 6.4, and 6.5.
3112 * The "load" command now supports writing to flash memory, if the remote
3113 stub provides the required support.
3115 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3116 longer requires symbolic debug information (e.g. DWARF-2).
3121 unset substitute-path
3122 show substitute-path
3123 Manage a list of substitution rules that GDB uses to rewrite the name
3124 of the directories where the sources are located. This can be useful
3125 for instance when the sources were moved to a different location
3126 between compilation and debugging.
3130 Print each CLI command as it is executed. Each command is prefixed with
3131 a number of `+' symbols representing the nesting depth.
3132 The source command now has a `-v' option to enable the same feature.
3136 The ARM Demon monitor support (RDP protocol, "target rdp").
3138 Kernel Object Display, an embedded debugging feature which only worked with
3139 an obsolete version of Cisco IOS.
3141 The 'set download-write-size' and 'show download-write-size' commands.
3143 * New remote packets
3146 Tell a stub about GDB client features, and request remote target features.
3147 The first feature implemented is PacketSize, which allows the target to
3148 specify the size of packets it can handle - to minimize the number of
3149 packets required and improve performance when connected to a remote
3153 Fetch an OS auxilliary vector from the remote stub. This packet is a
3154 more efficient replacement for qPart:auxv:read.
3156 qXfer:memory-map:read:
3157 Fetch a memory map from the remote stub, including information about
3158 RAM, ROM, and flash memory devices.
3163 Erase and program a flash memory device.
3165 * Removed remote packets
3168 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3169 used it, and only gdbserver implemented it.
3171 *** Changes in GDB 6.5
3175 Renesas M32C/M16C m32c-elf
3177 Morpho Technologies ms1 ms1-elf
3181 init-if-undefined Initialize a convenience variable, but
3182 only if it doesn't already have a value.
3184 The following commands are presently only implemented for native GNU/Linux:
3186 checkpoint Save a snapshot of the program state.
3188 restart <n> Return the program state to a
3189 previously saved state.
3191 info checkpoints List currently saved checkpoints.
3193 delete-checkpoint <n> Delete a previously saved checkpoint.
3195 set|show detach-on-fork Tell gdb whether to detach from a newly
3196 forked process, or to keep debugging it.
3198 info forks List forks of the user program that
3199 are available to be debugged.
3201 fork <n> Switch to debugging one of several
3202 forks of the user program that are
3203 available to be debugged.
3205 delete-fork <n> Delete a fork from the list of forks
3206 that are available to be debugged (and
3207 kill the forked process).
3209 detach-fork <n> Delete a fork from the list of forks
3210 that are available to be debugged (and
3211 allow the process to continue).
3215 Morpho Technologies ms2 ms1-elf
3217 * Improved Windows host support
3219 GDB now builds as a cross debugger hosted on i686-mingw32, including
3220 native console support, and remote communications using either
3221 network sockets or serial ports.
3223 * Improved Modula-2 language support
3225 GDB can now print most types in the Modula-2 syntax. This includes:
3226 basic types, set types, record types, enumerated types, range types,
3227 pointer types and ARRAY types. Procedure var parameters are correctly
3228 printed and hexadecimal addresses and character constants are also
3229 written in the Modula-2 syntax. Best results can be obtained by using
3230 GNU Modula-2 together with the -gdwarf-2 command line option.
3234 The ARM rdi-share module.
3236 The Netware NLM debug server.
3238 *** Changes in GDB 6.4
3240 * New native configurations
3242 OpenBSD/arm arm*-*-openbsd*
3243 OpenBSD/mips64 mips64-*-openbsd*
3247 Morpho Technologies ms1 ms1-elf
3249 * New command line options
3251 --batch-silent As for --batch, but totally silent.
3252 --return-child-result The debugger will exist with the same value
3253 the child (debugged) program exited with.
3254 --eval-command COMMAND, -ex COMMAND
3255 Execute a single GDB CLI command. This may be
3256 specified multiple times and in conjunction
3257 with the --command (-x) option.
3259 * Deprecated commands removed
3261 The following commands, that were deprecated in 2000, have been
3265 set|show arm disassembly-flavor set|show arm disassembler
3266 othernames set arm disassembler
3267 set|show remotedebug set|show debug remote
3268 set|show archdebug set|show debug arch
3269 set|show eventdebug set|show debug event
3272 * New BSD user-level threads support
3274 It is now possible to debug programs using the user-level threads
3275 library on OpenBSD and FreeBSD. Currently supported (target)
3278 FreeBSD/amd64 x86_64-*-freebsd*
3279 FreeBSD/i386 i386-*-freebsd*
3280 OpenBSD/i386 i386-*-openbsd*
3282 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3283 are not yet supported.
3285 * New support for Matsushita MN10300 w/sim added
3286 (Work in progress). mn10300-elf.
3288 * REMOVED configurations and files
3290 VxWorks and the XDR protocol *-*-vxworks
3291 Motorola MCORE mcore-*-*
3292 National Semiconductor NS32000 ns32k-*-*
3294 * New "set print array-indexes" command
3296 After turning this setting "on", GDB prints the index of each element
3297 when displaying arrays. The default is "off" to preserve the previous
3300 * VAX floating point support
3302 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3304 * User-defined command support
3306 In addition to using $arg0..$arg9 for argument passing, it is now possible
3307 to use $argc to determine now many arguments have been passed. See the
3308 section on user-defined commands in the user manual for more information.
3310 *** Changes in GDB 6.3:
3312 * New command line option
3314 GDB now accepts -l followed by a number to set the timeout for remote
3317 * GDB works with GCC -feliminate-dwarf2-dups
3319 GDB now supports a more compact representation of DWARF-2 debug
3320 information using DW_FORM_ref_addr references. These are produced
3321 by GCC with the option -feliminate-dwarf2-dups and also by some
3322 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3323 to use -feliminate-dwarf2-dups.
3325 * Internationalization
3327 When supported by the host system, GDB will be built with
3328 internationalization (libintl). The task of marking up the sources is
3329 continued, we're looking forward to our first translation.
3333 Initial support for debugging programs compiled with the GNAT
3334 implementation of the Ada programming language has been integrated
3335 into GDB. In this release, support is limited to expression evaluation.
3337 * New native configurations
3339 GNU/Linux/m32r m32r-*-linux-gnu
3343 GDB's remote protocol now includes support for the 'p' packet. This
3344 packet is used to fetch individual registers from a remote inferior.
3346 * END-OF-LIFE registers[] compatibility module
3348 GDB's internal register infrastructure has been completely rewritten.
3349 The new infrastructure making possible the implementation of key new
3350 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3353 GDB 6.3 will be the last release to include the the registers[]
3354 compatibility module that allowed out-of-date configurations to
3355 continue to work. This change directly impacts the following
3365 powerpc bdm protocol
3367 Unless there is activity to revive these configurations, they will be
3368 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3370 * OBSOLETE configurations and files
3372 Configurations that have been declared obsolete in this release have
3373 been commented out. Unless there is activity to revive these
3374 configurations, the next release of GDB will have their sources
3375 permanently REMOVED.
3384 *** Changes in GDB 6.2.1:
3386 * MIPS `break main; run' gave an heuristic-fence-post warning
3388 When attempting to run even a simple program, a warning about
3389 heuristic-fence-post being hit would be reported. This problem has
3392 * MIPS IRIX 'long double' crashed GDB
3394 When examining a long double variable, GDB would get a segmentation
3395 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3396 IRIX long double values).
3400 A bug in the VAX stack code was causing problems with the "next"
3401 command. This problem has been fixed.
3403 *** Changes in GDB 6.2:
3405 * Fix for ``many threads''
3407 On GNU/Linux systems that use the NPTL threads library, a program
3408 rapidly creating and deleting threads would confuse GDB leading to the
3411 ptrace: No such process.
3412 thread_db_get_info: cannot get thread info: generic error
3414 This problem has been fixed.
3416 * "-async" and "-noasync" options removed.
3418 Support for the broken "-noasync" option has been removed (it caused
3421 * New ``start'' command.
3423 This command runs the program until the begining of the main procedure.
3425 * New BSD Kernel Data Access Library (libkvm) interface
3427 Using ``target kvm'' it is now possible to debug kernel core dumps and
3428 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3429 platforms. Currently supported (native-only) configurations are:
3431 FreeBSD/amd64 x86_64-*-freebsd*
3432 FreeBSD/i386 i?86-*-freebsd*
3433 NetBSD/i386 i?86-*-netbsd*
3434 NetBSD/m68k m68*-*-netbsd*
3435 NetBSD/sparc sparc-*-netbsd*
3436 OpenBSD/amd64 x86_64-*-openbsd*
3437 OpenBSD/i386 i?86-*-openbsd*
3438 OpenBSD/m68k m68*-openbsd*
3439 OpenBSD/sparc sparc-*-openbsd*
3441 * Signal trampoline code overhauled
3443 Many generic problems with GDB's signal handling code have been fixed.
3444 These include: backtraces through non-contiguous stacks; recognition
3445 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3446 call; backtrace through a signal trampoline; step into and out of
3447 signal handlers; and single-stepping in the signal trampoline.
3449 Please note that kernel bugs are a limiting factor here. These
3450 features have been shown to work on an s390 GNU/Linux system that
3451 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3453 * Cygwin support for DWARF 2 added.
3455 * New native configurations
3457 GNU/Linux/hppa hppa*-*-linux*
3458 OpenBSD/hppa hppa*-*-openbsd*
3459 OpenBSD/m68k m68*-*-openbsd*
3460 OpenBSD/m88k m88*-*-openbsd*
3461 OpenBSD/powerpc powerpc-*-openbsd*
3462 NetBSD/vax vax-*-netbsd*
3463 OpenBSD/vax vax-*-openbsd*
3465 * END-OF-LIFE frame compatibility module
3467 GDB's internal frame infrastructure has been completely rewritten.
3468 The new infrastructure making it possible to support key new features
3469 including DWARF 2 Call Frame Information. To aid in the task of
3470 migrating old configurations to this new infrastructure, a
3471 compatibility module, that allowed old configurations to continue to
3472 work, was also included.
3474 GDB 6.2 will be the last release to include this frame compatibility
3475 module. This change directly impacts the following configurations:
3485 Unless there is activity to revive these configurations, they will be
3486 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3488 * REMOVED configurations and files
3490 Sun 3, running SunOS 3 m68*-*-sunos3*
3491 Sun 3, running SunOS 4 m68*-*-sunos4*
3492 Sun 2, running SunOS 3 m68000-*-sunos3*
3493 Sun 2, running SunOS 4 m68000-*-sunos4*
3494 Motorola 680x0 running LynxOS m68*-*-lynxos*
3495 AT&T 3b1/Unix pc m68*-att-*
3496 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3497 decstation mips-dec-* mips-little-*
3498 riscos mips-*-riscos* mips-*-sysv*
3499 sonymips mips-sony-*
3500 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3502 *** Changes in GDB 6.1.1:
3504 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3506 The TUI (Text-mode User Interface) is now built as part of a default
3507 GDB configuration. It is enabled by either selecting the TUI with the
3508 command line option "-i=tui" or by running the separate "gdbtui"
3509 program. For more information on the TUI, see the manual "Debugging
3512 * Pending breakpoint support (also included in GDB 6.1)
3514 Support has been added to allow you to specify breakpoints in shared
3515 libraries that have not yet been loaded. If a breakpoint location
3516 cannot be found, and the "breakpoint pending" option is set to auto,
3517 GDB queries you if you wish to make the breakpoint pending on a future
3518 shared-library load. If and when GDB resolves the breakpoint symbol,
3519 the pending breakpoint is removed as one or more regular breakpoints
3522 Pending breakpoints are very useful for GCJ Java debugging.
3524 * Fixed ISO-C build problems
3526 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3527 non ISO-C code that stopped them being built using a more strict ISO-C
3528 compiler (e.g., IBM's C compiler).
3530 * Fixed build problem on IRIX 5
3532 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3533 wasn't able to compile compile on an IRIX 5 system.
3535 * Added execute permission to gdb/gdbserver/configure
3537 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3538 permission. This bug would cause configure to fail on a number of
3539 systems (Solaris, IRIX). Ref: server/519.
3541 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3543 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3544 has been updated to use constant array sizes.
3546 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3548 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3549 its generated DWARF Call Frame Info. This encoding was causing GDB to
3550 panic, that panic has been fixed. Ref: gdb/1628.
3552 * Fixed a problem when examining parameters in shared library code.
3554 When examining parameters in optimized shared library code generated
3555 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3556 not available''. GDB now correctly displays the variable's value.
3558 *** Changes in GDB 6.1:
3560 * Removed --with-mmalloc
3562 Support for the mmalloc memory manager has been removed, as it
3563 conflicted with the internal gdb byte cache.
3565 * Changes in AMD64 configurations
3567 The AMD64 target now includes the %cs and %ss registers. As a result
3568 the AMD64 remote protocol has changed; this affects the floating-point
3569 and SSE registers. If you rely on those registers for your debugging,
3570 you should upgrade gdbserver on the remote side.
3572 * Revised SPARC target
3574 The SPARC target has been completely revised, incorporating the
3575 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3576 support for LynxOS and SunOS 4 has been dropped. Calling functions
3577 from within GDB on operating systems with a non-executable stack
3578 (Solaris, OpenBSD) now works.
3582 GDB has a new C++ demangler which does a better job on the mangled
3583 names generated by current versions of g++. It also runs faster, so
3584 with this and other changes gdb should now start faster on large C++
3587 * DWARF 2 Location Expressions
3589 GDB support for location expressions has been extended to support function
3590 arguments and frame bases. Older versions of GDB could crash when they
3593 * C++ nested types and namespaces
3595 GDB's support for nested types and namespaces in C++ has been
3596 improved, especially if you use the DWARF 2 debugging format. (This
3597 is the default for recent versions of GCC on most platforms.)
3598 Specifically, if you have a class "Inner" defined within a class or
3599 namespace "Outer", then GDB realizes that the class's name is
3600 "Outer::Inner", not simply "Inner". This should greatly reduce the
3601 frequency of complaints about not finding RTTI symbols. In addition,
3602 if you are stopped at inside of a function defined within a namespace,
3603 GDB modifies its name lookup accordingly.
3605 * New native configurations
3607 NetBSD/amd64 x86_64-*-netbsd*
3608 OpenBSD/amd64 x86_64-*-openbsd*
3609 OpenBSD/alpha alpha*-*-openbsd*
3610 OpenBSD/sparc sparc-*-openbsd*
3611 OpenBSD/sparc64 sparc64-*-openbsd*
3613 * New debugging protocols
3615 M32R with SDI protocol m32r-*-elf*
3617 * "set prompt-escape-char" command deleted.
3619 The command "set prompt-escape-char" has been deleted. This command,
3620 and its very obscure effet on GDB's prompt, was never documented,
3621 tested, nor mentioned in the NEWS file.
3623 * OBSOLETE configurations and files
3625 Configurations that have been declared obsolete in this release have
3626 been commented out. Unless there is activity to revive these
3627 configurations, the next release of GDB will have their sources
3628 permanently REMOVED.
3630 Sun 3, running SunOS 3 m68*-*-sunos3*
3631 Sun 3, running SunOS 4 m68*-*-sunos4*
3632 Sun 2, running SunOS 3 m68000-*-sunos3*
3633 Sun 2, running SunOS 4 m68000-*-sunos4*
3634 Motorola 680x0 running LynxOS m68*-*-lynxos*
3635 AT&T 3b1/Unix pc m68*-att-*
3636 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3637 decstation mips-dec-* mips-little-*
3638 riscos mips-*-riscos* mips-*-sysv*
3639 sonymips mips-sony-*
3640 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3642 * REMOVED configurations and files
3644 SGI Irix-4.x mips-sgi-irix4 or iris4
3645 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3646 Z8000 simulator z8k-zilog-none or z8ksim
3647 Matsushita MN10200 w/simulator mn10200-*-*
3648 H8/500 simulator h8500-hitachi-hms or h8500hms
3649 HP/PA running BSD hppa*-*-bsd*
3650 HP/PA running OSF/1 hppa*-*-osf*
3651 HP/PA Pro target hppa*-*-pro*
3652 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3653 386BSD i[3456]86-*-bsd*
3654 Sequent family i[3456]86-sequent-sysv4*
3655 i[3456]86-sequent-sysv*
3656 i[3456]86-sequent-bsd*
3657 SPARC running LynxOS sparc-*-lynxos*
3658 SPARC running SunOS 4 sparc-*-sunos4*
3659 Tsqware Sparclet sparclet-*-*
3660 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3662 *** Changes in GDB 6.0:
3666 Support for debugging the Objective-C programming language has been
3667 integrated into GDB.
3669 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3671 DWARF 2's Call Frame Information makes available compiler generated
3672 information that more exactly describes the program's run-time stack.
3673 By using this information, GDB is able to provide more robust stack
3676 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3677 have been updated to use a new backtrace mechanism which includes
3678 DWARF 2 CFI support.
3682 GDB's remote protocol has been extended to include support for hosted
3683 file I/O (where the remote target uses GDB's file system). See GDB's
3684 remote protocol documentation for details.
3686 * All targets using the new architecture framework.
3688 All of GDB's targets have been updated to use the new internal
3689 architecture framework. The way is now open for future GDB releases
3690 to include cross-architecture native debugging support (i386 on amd64,
3693 * GNU/Linux's Thread Local Storage (TLS)
3695 GDB now includes support for for the GNU/Linux implementation of
3696 per-thread variables.
3698 * GNU/Linux's Native POSIX Thread Library (NPTL)
3700 GDB's thread code has been updated to work with either the new
3701 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3703 * Separate debug info.
3705 GDB, in conjunction with BINUTILS, now supports a mechanism for
3706 automatically loading debug information from a separate file. Instead
3707 of shipping full debug and non-debug versions of system libraries,
3708 system integrators can now instead ship just the stripped libraries
3709 and optional debug files.
3711 * DWARF 2 Location Expressions
3713 DWARF 2 Location Expressions allow the compiler to more completely
3714 describe the location of variables (even in optimized code) to the
3717 GDB now includes preliminary support for location expressions (support
3718 for DW_OP_piece is still missing).
3722 A number of long standing bugs that caused GDB to die while starting a
3723 Java application have been fixed. GDB's Java support is now
3724 considered "useable".
3726 * GNU/Linux support for fork, vfork, and exec.
3728 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3729 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3732 * GDB supports logging output to a file
3734 There are two new commands, "set logging" and "show logging", which can be
3735 used to capture GDB's output to a file.
3737 * The meaning of "detach" has changed for gdbserver
3739 The "detach" command will now resume the application, as documented. To
3740 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3743 * d10v, m68hc11 `regs' command deprecated
3745 The `info registers' command has been updated so that it displays the
3746 registers using a format identical to the old `regs' command.
3750 A new command, "maint set profile on/off", has been added. This command can
3751 be used to enable or disable profiling while running GDB, to profile a
3752 session or a set of commands. In addition there is a new configure switch,
3753 "--enable-profiling", which will cause GDB to be compiled with profiling
3754 data, for more informative profiling results.
3756 * Default MI syntax changed to "mi2".
3758 The default MI (machine interface) syntax, enabled by the command line
3759 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3760 "mi1", can be enabled by specifying the option "-i=mi1".
3762 Support for the original "mi0" syntax (included in GDB 5.0) has been
3765 Fix for gdb/192: removed extraneous space when displaying frame level.
3766 Fix for gdb/672: update changelist is now output in mi list format.
3767 Fix for gdb/702: a -var-assign that updates the value now shows up
3768 in a subsequent -var-update.
3770 * New native configurations.
3772 FreeBSD/amd64 x86_64-*-freebsd*
3774 * Multi-arched targets.
3776 HP/PA HPUX11 hppa*-*-hpux*
3777 Renesas M32R/D w/simulator m32r-*-elf*
3779 * OBSOLETE configurations and files
3781 Configurations that have been declared obsolete in this release have
3782 been commented out. Unless there is activity to revive these
3783 configurations, the next release of GDB will have their sources
3784 permanently REMOVED.
3786 Z8000 simulator z8k-zilog-none or z8ksim
3787 Matsushita MN10200 w/simulator mn10200-*-*
3788 H8/500 simulator h8500-hitachi-hms or h8500hms
3789 HP/PA running BSD hppa*-*-bsd*
3790 HP/PA running OSF/1 hppa*-*-osf*
3791 HP/PA Pro target hppa*-*-pro*
3792 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3793 Sequent family i[3456]86-sequent-sysv4*
3794 i[3456]86-sequent-sysv*
3795 i[3456]86-sequent-bsd*
3796 Tsqware Sparclet sparclet-*-*
3797 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3799 * REMOVED configurations and files
3802 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3803 IBM AIX PS/2 i[3456]86-*-aix
3804 i386 running Mach 3.0 i[3456]86-*-mach3*
3805 i386 running Mach i[3456]86-*-mach*
3806 i386 running OSF/1 i[3456]86-*osf1mk*
3807 HP/Apollo 68k Family m68*-apollo*-sysv*,
3809 m68*-hp-bsd*, m68*-hp-hpux*
3810 Argonaut Risc Chip (ARC) arc-*-*
3811 Mitsubishi D30V d30v-*-*
3812 Fujitsu FR30 fr30-*-elf*
3813 OS/9000 i[34]86-*-os9k
3814 I960 with MON960 i960-*-coff
3816 * MIPS $fp behavior changed
3818 The convenience variable $fp, for the MIPS, now consistently returns
3819 the address of the current frame's base. Previously, depending on the
3820 context, $fp could refer to either $sp or the current frame's base
3821 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3822 The GNU Source-Level Debugger''.
3824 *** Changes in GDB 5.3:
3826 * GNU/Linux shared library multi-threaded performance improved.
3828 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3829 `/proc', in preference to `ptrace' for memory reads. This may result
3830 in an improvement in the start-up time of multi-threaded, shared
3831 library applications when run under GDB. One GDB user writes: ``loads
3832 shared libs like mad''.
3834 * ``gdbserver'' now supports multi-threaded applications on some targets
3836 Support for debugging multi-threaded applications which use
3837 the GNU/Linux LinuxThreads package has been added for
3838 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3839 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3841 * GDB now supports C/C++ preprocessor macros.
3843 GDB now expands preprocessor macro invocations in C/C++ expressions,
3844 and provides various commands for showing macro definitions and how
3847 The new command `macro expand EXPRESSION' expands any macro
3848 invocations in expression, and shows the result.
3850 The new command `show macro MACRO-NAME' shows the definition of the
3851 macro named MACRO-NAME, and where it was defined.
3853 Most compilers don't include information about macros in the debugging
3854 information by default. In GCC 3.1, for example, you need to compile
3855 your program with the options `-gdwarf-2 -g3'. If the macro
3856 information is present in the executable, GDB will read it.
3858 * Multi-arched targets.
3860 DEC Alpha (partial) alpha*-*-*
3861 DEC VAX (partial) vax-*-*
3863 National Semiconductor NS32000 (partial) ns32k-*-*
3864 Motorola 68000 (partial) m68k-*-*
3865 Motorola MCORE mcore-*-*
3869 Fujitsu FRV architecture added by Red Hat frv*-*-*
3872 * New native configurations
3874 Alpha NetBSD alpha*-*-netbsd*
3875 SH NetBSD sh*-*-netbsdelf*
3876 MIPS NetBSD mips*-*-netbsd*
3877 UltraSPARC NetBSD sparc64-*-netbsd*
3879 * OBSOLETE configurations and files
3881 Configurations that have been declared obsolete in this release have
3882 been commented out. Unless there is activity to revive these
3883 configurations, the next release of GDB will have their sources
3884 permanently REMOVED.
3886 Mitsubishi D30V d30v-*-*
3887 OS/9000 i[34]86-*-os9k
3888 IBM AIX PS/2 i[3456]86-*-aix
3889 Fujitsu FR30 fr30-*-elf*
3890 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3891 Argonaut Risc Chip (ARC) arc-*-*
3892 i386 running Mach 3.0 i[3456]86-*-mach3*
3893 i386 running Mach i[3456]86-*-mach*
3894 i386 running OSF/1 i[3456]86-*osf1mk*
3895 HP/Apollo 68k Family m68*-apollo*-sysv*,
3897 m68*-hp-bsd*, m68*-hp-hpux*
3898 I960 with MON960 i960-*-coff
3900 * OBSOLETE languages
3902 CHILL, a Pascal like language used by telecommunications companies.
3904 * REMOVED configurations and files
3906 AMD 29k family via UDI a29k-amd-udi, udi29k
3907 A29K VxWorks a29k-*-vxworks
3908 AMD 29000 embedded, using EBMON a29k-none-none
3909 AMD 29000 embedded with COFF a29k-none-coff
3910 AMD 29000 embedded with a.out a29k-none-aout
3912 testsuite/gdb.hp/gdb.threads-hp/ directory
3914 * New command "set max-user-call-depth <nnn>"
3916 This command allows the user to limit the call depth of user-defined
3917 commands. The default is 1024.
3919 * Changes in FreeBSD/i386 native debugging.
3921 Support for the "generate-core-file" has been added.
3923 * New commands "dump", "append", and "restore".
3925 These commands allow data to be copied from target memory
3926 to a bfd-format or binary file (dump and append), and back
3927 from a file into memory (restore).
3929 * Improved "next/step" support on multi-processor Alpha Tru64.
3931 The previous single-step mechanism could cause unpredictable problems,
3932 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3933 of a software single-step mechanism prevents this.
3935 *** Changes in GDB 5.2.1:
3943 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3944 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3945 Fix, by Joel Brobecker imported from mainline.
3947 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3948 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3949 Fix, by Fred Fish, imported from mainline.
3951 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3952 Surprisingly enough, it works now.
3953 By Michal Ludvig, imported from mainline.
3955 i386 hardware watchpoint support:
3956 avoid misses on second run for some targets.
3957 By Pierre Muller, imported from mainline.
3959 *** Changes in GDB 5.2:
3961 * New command "set trust-readonly-sections on[off]".
3963 This command is a hint that tells gdb that read-only sections
3964 really are read-only (ie. that their contents will not change).
3965 In this mode, gdb will go to the object file rather than the
3966 target to read memory from read-only sections (such as ".text").
3967 This can be a significant performance improvement on some
3968 (notably embedded) targets.
3970 * New command "generate-core-file" (or "gcore").
3972 This new gdb command allows the user to drop a core file of the child
3973 process state at any time. So far it's been implemented only for
3974 GNU/Linux and Solaris, but should be relatively easily ported to other
3975 hosts. Argument is core file name (defaults to core.<pid>).
3977 * New command line option
3979 GDB now accepts --pid or -p followed by a process id.
3981 * Change in command line behavior -- corefiles vs. process ids.
3983 There is a subtle behavior in the way in which GDB handles
3984 command line arguments. The first non-flag argument is always
3985 a program to debug, but the second non-flag argument may either
3986 be a corefile or a process id. Previously, GDB would attempt to
3987 open the second argument as a corefile, and if that failed, would
3988 issue a superfluous error message and then attempt to attach it as
3989 a process. Now, if the second argument begins with a non-digit,
3990 it will be treated as a corefile. If it begins with a digit,
3991 GDB will attempt to attach it as a process, and if no such process
3992 is found, will then attempt to open it as a corefile.
3994 * Changes in ARM configurations.
3996 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3997 configuration is fully multi-arch.
3999 * New native configurations
4001 ARM NetBSD arm*-*-netbsd*
4002 x86 OpenBSD i[3456]86-*-openbsd*
4003 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4004 Sparc64 running FreeBSD sparc64-*-freebsd*
4008 Sanyo XStormy16 xstormy16-elf
4010 * OBSOLETE configurations and files
4012 Configurations that have been declared obsolete in this release have
4013 been commented out. Unless there is activity to revive these
4014 configurations, the next release of GDB will have their sources
4015 permanently REMOVED.
4017 AMD 29k family via UDI a29k-amd-udi, udi29k
4018 A29K VxWorks a29k-*-vxworks
4019 AMD 29000 embedded, using EBMON a29k-none-none
4020 AMD 29000 embedded with COFF a29k-none-coff
4021 AMD 29000 embedded with a.out a29k-none-aout
4023 testsuite/gdb.hp/gdb.threads-hp/ directory
4025 * REMOVED configurations and files
4027 TI TMS320C80 tic80-*-*
4029 PowerPC Solaris powerpcle-*-solaris*
4030 PowerPC Windows NT powerpcle-*-cygwin32
4031 PowerPC Netware powerpc-*-netware*
4032 Harris/CXUX m88k m88*-harris-cxux*
4033 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4034 ns32k-utek-sysv* ns32k-utek-*
4035 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4036 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4037 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4038 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4039 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4041 * Changes to command line processing
4043 The new `--args' feature can be used to specify command-line arguments
4044 for the inferior from gdb's command line.
4046 * Changes to key bindings
4048 There is a new `operate-and-get-next' function bound to `C-o'.
4050 *** Changes in GDB 5.1.1
4052 Fix compile problem on DJGPP.
4054 Fix a problem with floating-point registers on the i386 being
4057 Fix to stop GDB crashing on .debug_str debug info.
4059 Numerous documentation fixes.
4061 Numerous testsuite fixes.
4063 *** Changes in GDB 5.1:
4065 * New native configurations
4067 Alpha FreeBSD alpha*-*-freebsd*
4068 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4069 MIPS GNU/Linux mips*-*-linux*
4070 MIPS SGI Irix 6.x mips*-sgi-irix6*
4071 ia64 AIX ia64-*-aix*
4072 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4076 Motorola 68HC11 and 68HC12 m68hc11-elf
4078 UltraSparc running GNU/Linux sparc64-*-linux*
4080 * OBSOLETE configurations and files
4082 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4083 Harris/CXUX m88k m88*-harris-cxux*
4084 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4085 ns32k-utek-sysv* ns32k-utek-*
4086 TI TMS320C80 tic80-*-*
4088 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4089 PowerPC Solaris powerpcle-*-solaris*
4090 PowerPC Windows NT powerpcle-*-cygwin32
4091 PowerPC Netware powerpc-*-netware*
4092 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4093 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4094 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4095 Apple Macintosh (MPW) host N/A
4097 stuff.c (Program to stuff files into a specially prepared space in kdb)
4098 kdb-start.c (Main loop for the standalone kernel debugger)
4100 Configurations that have been declared obsolete in this release have
4101 been commented out. Unless there is activity to revive these
4102 configurations, the next release of GDB will have their sources
4103 permanently REMOVED.
4105 * REMOVED configurations and files
4107 Altos 3068 m68*-altos-*
4108 Convex c1-*-*, c2-*-*
4110 ARM RISCix arm-*-* (as host)
4114 * GDB has been converted to ISO C.
4116 GDB's source code has been converted to ISO C. In particular, the
4117 sources are fully protoized, and rely on standard headers being
4122 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4124 * The MI enabled by default.
4126 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4127 revised and enabled by default. Packages which use GDB as a debugging
4128 engine behind a UI or another front end are encouraged to switch to
4129 using the GDB/MI interface, instead of the old annotations interface
4130 which is now deprecated.
4132 * Support for debugging Pascal programs.
4134 GDB now includes support for debugging Pascal programs. The following
4135 main features are supported:
4137 - Pascal-specific data types such as sets;
4139 - automatic recognition of Pascal sources based on file-name
4142 - Pascal-style display of data types, variables, and functions;
4144 - a Pascal expression parser.
4146 However, some important features are not yet supported.
4148 - Pascal string operations are not supported at all;
4150 - there are some problems with boolean types;
4152 - Pascal type hexadecimal constants are not supported
4153 because they conflict with the internal variables format;
4155 - support for Pascal objects and classes is not full yet;
4157 - unlike Pascal, GDB is case-sensitive for symbol names.
4159 * Changes in completion.
4161 Commands such as `shell', `run' and `set args', which pass arguments
4162 to inferior programs, now complete on file names, similar to what
4163 users expect at the shell prompt.
4165 Commands which accept locations, such as `disassemble', `print',
4166 `breakpoint', `until', etc. now complete on filenames as well as
4167 program symbols. Thus, if you type "break foob TAB", and the source
4168 files linked into the programs include `foobar.c', that file name will
4169 be one of the candidates for completion. However, file names are not
4170 considered for completion after you typed a colon that delimits a file
4171 name from a name of a function in that file, as in "break foo.c:bar".
4173 `set demangle-style' completes on available demangling styles.
4175 * New platform-independent commands:
4177 It is now possible to define a post-hook for a command as well as a
4178 hook that runs before the command. For more details, see the
4179 documentation of `hookpost' in the GDB manual.
4181 * Changes in GNU/Linux native debugging.
4183 Support for debugging multi-threaded programs has been completely
4184 revised for all platforms except m68k and sparc. You can now debug as
4185 many threads as your system allows you to have.
4187 Attach/detach is supported for multi-threaded programs.
4189 Support for SSE registers was added for x86. This doesn't work for
4190 multi-threaded programs though.
4192 * Changes in MIPS configurations.
4194 Multi-arch support is enabled for all MIPS configurations.
4196 GDB can now be built as native debugger on SGI Irix 6.x systems for
4197 debugging n32 executables. (Debugging 64-bit executables is not yet
4200 * Unified support for hardware watchpoints in all x86 configurations.
4202 Most (if not all) native x86 configurations support hardware-assisted
4203 breakpoints and watchpoints in a unified manner. This support
4204 implements debug register sharing between watchpoints, which allows to
4205 put a virtually infinite number of watchpoints on the same address,
4206 and also supports watching regions up to 16 bytes with several debug
4209 The new maintenance command `maintenance show-debug-regs' toggles
4210 debugging print-outs in functions that insert, remove, and test
4211 watchpoints and hardware breakpoints.
4213 * Changes in the DJGPP native configuration.
4215 New command ``info dos sysinfo'' displays assorted information about
4216 the CPU, OS, memory, and DPMI server.
4218 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4219 display information about segment descriptors stored in GDT, LDT, and
4222 New commands ``info dos pde'' and ``info dos pte'' display entries
4223 from Page Directory and Page Tables (for now works with CWSDPMI only).
4224 New command ``info dos address-pte'' displays the Page Table entry for
4225 a given linear address.
4227 GDB can now pass command lines longer than 126 characters to the
4228 program being debugged (requires an update to the libdbg.a library
4229 which is part of the DJGPP development kit).
4231 DWARF2 debug info is now supported.
4233 It is now possible to `step' and `next' through calls to `longjmp'.
4235 * Changes in documentation.
4237 All GDB documentation was converted to GFDL, the GNU Free
4238 Documentation License.
4240 Tracepoints-related commands are now fully documented in the GDB
4243 TUI, the Text-mode User Interface, is now documented in the manual.
4245 Tracepoints-related commands are now fully documented in the GDB
4248 The "GDB Internals" manual now has an index. It also includes
4249 documentation of `ui_out' functions, GDB coding standards, x86
4250 hardware watchpoints, and memory region attributes.
4252 * GDB's version number moved to ``version.in''
4254 The Makefile variable VERSION has been replaced by the file
4255 ``version.in''. People creating GDB distributions should update the
4256 contents of this file.
4260 GUD support is now a standard part of the EMACS distribution.
4262 *** Changes in GDB 5.0:
4264 * Improved support for debugging FP programs on x86 targets
4266 Unified and much-improved support for debugging floating-point
4267 programs on all x86 targets. In particular, ``info float'' now
4268 displays the FP registers in the same format on all x86 targets, with
4269 greater level of detail.
4271 * Improvements and bugfixes in hardware-assisted watchpoints
4273 It is now possible to watch array elements, struct members, and
4274 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4275 on x86 targets no longer erroneously trigger when the address is
4278 * Improvements in the native DJGPP version of GDB
4280 The distribution now includes all the scripts and auxiliary files
4281 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4282 machines ``out of the box''.
4284 The DJGPP version can now debug programs that use signals. It is
4285 possible to catch signals that happened in the debuggee, deliver
4286 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4287 would kill the program being debugged.) Programs that hook hardware
4288 interrupts (keyboard, timer, etc.) can also be debugged.
4290 It is now possible to debug DJGPP programs that redirect their
4291 standard handles or switch them to raw (as opposed to cooked) mode, or
4292 even close them. The command ``run < foo > bar'' works as expected,
4293 and ``info terminal'' reports useful information about the debuggee's
4294 terminal, including raw/cooked mode, redirection, etc.
4296 The DJGPP version now uses termios functions for console I/O, which
4297 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4300 DOS-style file names with drive letters are now fully supported by
4303 It is now possible to debug DJGPP programs that switch their working
4304 directory. It is also possible to rerun the debuggee any number of
4305 times without restarting GDB; thus, you can use the same setup,
4306 breakpoints, etc. for many debugging sessions.
4308 * New native configurations
4310 ARM GNU/Linux arm*-*-linux*
4311 PowerPC GNU/Linux powerpc-*-linux*
4315 Motorola MCore mcore-*-*
4316 x86 VxWorks i[3456]86-*-vxworks*
4317 PowerPC VxWorks powerpc-*-vxworks*
4318 TI TMS320C80 tic80-*-*
4320 * OBSOLETE configurations
4322 Altos 3068 m68*-altos-*
4323 Convex c1-*-*, c2-*-*
4325 ARM RISCix arm-*-* (as host)
4328 Configurations that have been declared obsolete will be commented out,
4329 but the code will be left in place. If there is no activity to revive
4330 these configurations before the next release of GDB, the sources will
4331 be permanently REMOVED.
4333 * Gould support removed
4335 Support for the Gould PowerNode and NP1 has been removed.
4337 * New features for SVR4
4339 On SVR4 native platforms (such as Solaris), if you attach to a process
4340 without first loading a symbol file, GDB will now attempt to locate and
4341 load symbols from the running process's executable file.
4343 * Many C++ enhancements
4345 C++ support has been greatly improved. Overload resolution now works properly
4346 in almost all cases. RTTI support is on the way.
4348 * Remote targets can connect to a sub-program
4350 A popen(3) style serial-device has been added. This device starts a
4351 sub-process (such as a stand-alone simulator) and then communicates
4352 with that. The sub-program to run is specified using the syntax
4353 ``|<program> <args>'' vis:
4355 (gdb) set remotedebug 1
4356 (gdb) target extended-remote |mn10300-elf-sim program-args
4358 * MIPS 64 remote protocol
4360 A long standing bug in the mips64 remote protocol where by GDB
4361 expected certain 32 bit registers (ex SR) to be transfered as 32
4362 instead of 64 bits has been fixed.
4364 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4365 added to provide backward compatibility with older versions of GDB.
4367 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4369 The command ``set remotebinarydownload'' command has been replaced by
4370 ``set remote X-packet''. Other commands in ``set remote'' family
4371 include ``set remote P-packet''.
4373 * Breakpoint commands accept ranges.
4375 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4376 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4377 ``tracepoint passcount'' also accepts a range of tracepoints.
4379 * ``apropos'' command added.
4381 The ``apropos'' command searches through command names and
4382 documentation strings, printing out matches, making it much easier to
4383 try to find a command that does what you are looking for.
4387 A new machine oriented interface (MI) has been added to GDB. This
4388 interface is designed for debug environments running GDB as a separate
4389 process. This is part of the long term libGDB project. See the
4390 "GDB/MI" chapter of the GDB manual for further information. It can be
4391 enabled by configuring with:
4393 .../configure --enable-gdbmi
4395 *** Changes in GDB-4.18:
4397 * New native configurations
4399 HP-UX 10.20 hppa*-*-hpux10.20
4400 HP-UX 11.x hppa*-*-hpux11.0*
4401 M68K GNU/Linux m68*-*-linux*
4405 Fujitsu FR30 fr30-*-elf*
4406 Intel StrongARM strongarm-*-*
4407 Mitsubishi D30V d30v-*-*
4409 * OBSOLETE configurations
4411 Gould PowerNode, NP1 np1-*-*, pn-*-*
4413 Configurations that have been declared obsolete will be commented out,
4414 but the code will be left in place. If there is no activity to revive
4415 these configurations before the next release of GDB, the sources will
4416 be permanently REMOVED.
4420 As a compatibility experiment, GDB's source files buildsym.h and
4421 buildsym.c have been converted to pure standard C, no longer
4422 containing any K&R compatibility code. We believe that all systems in
4423 use today either come with a standard C compiler, or have a GCC port
4424 available. If this is not true, please report the affected
4425 configuration to bug-gdb@gnu.org immediately. See the README file for
4426 information about getting a standard C compiler if you don't have one
4431 GDB now uses readline 2.2.
4433 * set extension-language
4435 You can now control the mapping between filename extensions and source
4436 languages by using the `set extension-language' command. For instance,
4437 you can ask GDB to treat .c files as C++ by saying
4438 set extension-language .c c++
4439 The command `info extensions' lists all of the recognized extensions
4440 and their associated languages.
4442 * Setting processor type for PowerPC and RS/6000
4444 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4445 you can use the `set processor' command to specify what variant of the
4446 PowerPC family you are debugging. The command
4450 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4451 following PowerPC and RS6000 variants:
4453 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4454 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4456 403GC IBM PowerPC 403GC
4457 505 Motorola PowerPC 505
4458 860 Motorola PowerPC 860 or 850
4459 601 Motorola PowerPC 601
4460 602 Motorola PowerPC 602
4461 603 Motorola/IBM PowerPC 603 or 603e
4462 604 Motorola PowerPC 604 or 604e
4463 750 Motorola/IBM PowerPC 750 or 750
4465 At the moment, this command just tells GDB what to name the
4466 special-purpose processor registers. Since almost all the affected
4467 registers are inaccessible to user-level programs, this command is
4468 only useful for remote debugging in its present form.
4472 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4473 more extensive support for HP-UX. Added features include shared
4474 library support, kernel threads and hardware watchpoints for 11.00,
4475 support for HP's ANSI C and C++ compilers, and a compatibility mode
4476 for xdb and dbx commands.
4480 HP's donation includes the new concept of catchpoints, which is a
4481 generalization of the old catch command. On HP-UX, it is now possible
4482 to catch exec, fork, and vfork, as well as library loading.
4484 This means that the existing catch command has changed; its first
4485 argument now specifies the type of catch to be set up. See the
4486 output of "help catch" for a list of catchpoint types.
4488 * Debugging across forks
4490 On HP-UX, you can choose which process to debug when a fork() happens
4495 HP has donated a curses-based terminal user interface (TUI). To get
4496 it, build with --enable-tui. Although this can be enabled for any
4497 configuration, at present it only works for native HP debugging.
4499 * GDB remote protocol additions
4501 A new protocol packet 'X' that writes binary data is now available.
4502 Default behavior is to try 'X', then drop back to 'M' if the stub
4503 fails to respond. The settable variable `remotebinarydownload'
4504 allows explicit control over the use of 'X'.
4506 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4507 full 64-bit address. The command
4509 set remoteaddresssize 32
4511 can be used to revert to the old behaviour. For existing remote stubs
4512 the change should not be noticed, as the additional address information
4515 In order to assist in debugging stubs, you may use the maintenance
4516 command `packet' to send any text string to the stub. For instance,
4518 maint packet heythere
4520 sends the packet "$heythere#<checksum>". Note that it is very easy to
4521 disrupt a debugging session by sending the wrong packet at the wrong
4524 The compare-sections command allows you to compare section data on the
4525 target to what is in the executable file without uploading or
4526 downloading, by comparing CRC checksums.
4528 * Tracing can collect general expressions
4530 You may now collect general expressions at tracepoints. This requires
4531 further additions to the target-side stub; see tracepoint.c and
4532 doc/agentexpr.texi for further details.
4534 * mask-address variable for Mips
4536 For Mips targets, you may control the zeroing of the upper 32 bits of
4537 a 64-bit address by entering `set mask-address on'. This is mainly
4538 of interest to users of embedded R4xxx and R5xxx processors.
4540 * Higher serial baud rates
4542 GDB's serial code now allows you to specify baud rates 57600, 115200,
4543 230400, and 460800 baud. (Note that your host system may not be able
4544 to achieve all of these rates.)
4548 The i960 configuration now includes an initial implementation of a
4549 builtin simulator, contributed by Jim Wilson.
4552 *** Changes in GDB-4.17:
4554 * New native configurations
4556 Alpha GNU/Linux alpha*-*-linux*
4557 Unixware 2.x i[3456]86-unixware2*
4558 Irix 6.x mips*-sgi-irix6*
4559 PowerPC GNU/Linux powerpc-*-linux*
4560 PowerPC Solaris powerpcle-*-solaris*
4561 Sparc GNU/Linux sparc-*-linux*
4562 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4566 Argonaut Risc Chip (ARC) arc-*-*
4567 Hitachi H8/300S h8300*-*-*
4568 Matsushita MN10200 w/simulator mn10200-*-*
4569 Matsushita MN10300 w/simulator mn10300-*-*
4570 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4571 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4572 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4573 Mitsubishi D10V w/simulator d10v-*-*
4574 Mitsubishi M32R/D w/simulator m32r-*-elf*
4575 Tsqware Sparclet sparclet-*-*
4576 NEC V850 w/simulator v850-*-*
4578 * New debugging protocols
4580 ARM with RDI protocol arm*-*-*
4581 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4582 DDB and LSI variants of PMON protocol mips*-*-*
4583 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4584 PowerPC with SDS protocol powerpc{,le}-*-eabi
4585 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4589 All configurations can now understand and use the DWARF 2 debugging
4590 format. The choice is automatic, if the symbol file contains DWARF 2
4595 GDB now includes basic Java language support. This support is
4596 only useful with Java compilers that produce native machine code.
4598 * solib-absolute-prefix and solib-search-path
4600 For SunOS and SVR4 shared libraries, you may now set the prefix for
4601 loading absolute shared library symbol files, and the search path for
4602 locating non-absolute shared library symbol files.
4604 * Live range splitting
4606 GDB can now effectively debug code for which GCC has performed live
4607 range splitting as part of its optimization. See gdb/doc/LRS for
4608 more details on the expected format of the stabs information.
4612 GDB's support for the GNU Hurd, including thread debugging, has been
4613 updated to work with current versions of the Hurd.
4617 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4618 instruction set. ARM GDB automatically detects when Thumb
4619 instructions are in use, and adjusts disassembly and backtracing
4624 GDB's MIPS target configurations now handle the MIP16 16-bit
4629 GDB now includes support for overlays; if an executable has been
4630 linked such that multiple sections are based at the same address, GDB
4631 will decide which section to use for symbolic info. You can choose to
4632 control the decision manually, using overlay commands, or implement
4633 additional target-side support and use "overlay load-target" to bring
4634 in the overlay mapping. Do "help overlay" for more detail.
4638 The command "info symbol <address>" displays information about
4639 the symbol at the specified address.
4643 The standard remote protocol now includes an extension that allows
4644 asynchronous collection and display of trace data. This requires
4645 extensive support in the target-side debugging stub. Tracing mode
4646 includes a new interaction mode in GDB and new commands: see the
4647 file tracepoint.c for more details.
4651 Configurations for embedded MIPS now include a simulator contributed
4652 by Cygnus Solutions. The simulator supports the instruction sets
4653 of most MIPS variants.
4657 Sparc configurations may now include the ERC32 simulator contributed
4658 by the European Space Agency. The simulator is not built into
4659 Sparc targets by default; configure with --enable-sim to include it.
4663 For target configurations that may include multiple variants of a
4664 basic architecture (such as MIPS and SH), you may now set the
4665 architecture explicitly. "set arch" sets, "info arch" lists
4666 the possible architectures.
4668 *** Changes in GDB-4.16:
4670 * New native configurations
4672 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4673 M68K NetBSD m68k-*-netbsd*
4674 PowerPC AIX 4.x powerpc-*-aix*
4675 PowerPC MacOS powerpc-*-macos*
4676 PowerPC Windows NT powerpcle-*-cygwin32
4677 RS/6000 AIX 4.x rs6000-*-aix4*
4681 ARM with RDP protocol arm-*-*
4682 I960 with MON960 i960-*-coff
4683 MIPS VxWorks mips*-*-vxworks*
4684 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4685 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4687 Matra Sparclet sparclet-*-*
4691 The powerpc-eabi configuration now includes the PSIM simulator,
4692 contributed by Andrew Cagney, with assistance from Mike Meissner.
4693 PSIM is a very elaborate model of the PowerPC, including not only
4694 basic instruction set execution, but also details of execution unit
4695 performance and I/O hardware. See sim/ppc/README for more details.
4699 GDB now works with Solaris 2.5.
4701 * Windows 95/NT native
4703 GDB will now work as a native debugger on Windows 95 and Windows NT.
4704 To build it from source, you must use the "gnu-win32" environment,
4705 which uses a DLL to emulate enough of Unix to run the GNU tools.
4706 Further information, binaries, and sources are available at
4707 ftp.cygnus.com, under pub/gnu-win32.
4709 * dont-repeat command
4711 If a user-defined command includes the command `dont-repeat', then the
4712 command will not be repeated if the user just types return. This is
4713 useful if the command is time-consuming to run, so that accidental
4714 extra keystrokes don't run the same command many times.
4716 * Send break instead of ^C
4718 The standard remote protocol now includes an option to send a break
4719 rather than a ^C to the target in order to interrupt it. By default,
4720 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4722 * Remote protocol timeout
4724 The standard remote protocol includes a new variable `remotetimeout'
4725 that allows you to set the number of seconds before GDB gives up trying
4726 to read from the target. The default value is 2.
4728 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4730 By default GDB will automatically keep track of objects as they are
4731 loaded and unloaded by the dynamic linker. By using the command `set
4732 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4733 when shared library events occur, thus allowing you to set breakpoints
4734 in shared libraries which are explicitly loaded by the inferior.
4736 Note this feature does not work on hpux8. On hpux9 you must link
4737 /usr/lib/end.o into your program. This feature should work
4738 automatically on hpux10.
4740 * Irix 5.x hardware watchpoint support
4742 Irix 5 configurations now support the use of hardware watchpoints.
4744 * Mips protocol "SYN garbage limit"
4746 When debugging a Mips target using the `target mips' protocol, you
4747 may set the number of characters that GDB will ignore by setting
4748 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4749 every character. The default value is 1050.
4751 * Recording and replaying remote debug sessions
4753 If you set `remotelogfile' to the name of a file, gdb will write to it
4754 a recording of a remote debug session. This recording may then be
4755 replayed back to gdb using "gdbreplay". See gdbserver/README for
4756 details. This is useful when you have a problem with GDB while doing
4757 remote debugging; you can make a recording of the session and send it
4758 to someone else, who can then recreate the problem.
4760 * Speedups for remote debugging
4762 GDB includes speedups for downloading and stepping MIPS systems using
4763 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4764 and more efficient S-record downloading.
4766 * Memory use reductions and statistics collection
4768 GDB now uses less memory and reports statistics about memory usage.
4769 Try the `maint print statistics' command, for example.
4771 *** Changes in GDB-4.15:
4773 * Psymtabs for XCOFF
4775 The symbol reader for AIX GDB now uses partial symbol tables. This
4776 can greatly improve startup time, especially for large executables.
4778 * Remote targets use caching
4780 Remote targets now use a data cache to speed up communication with the
4781 remote side. The data cache could lead to incorrect results because
4782 it doesn't know about volatile variables, thus making it impossible to
4783 debug targets which use memory mapped I/O devices. `set remotecache
4784 off' turns the the data cache off.
4786 * Remote targets may have threads
4788 The standard remote protocol now includes support for multiple threads
4789 in the target system, using new protocol commands 'H' and 'T'. See
4790 gdb/remote.c for details.
4794 If GDB is configured with `--enable-netrom', then it will include
4795 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4796 acts as though it is a bank of ROM on the target board, but you can
4797 write into it over the network. GDB's support consists only of
4798 support for fast loading into the emulated ROM; to debug, you must use
4799 another protocol, such as standard remote protocol. The usual
4800 sequence is something like
4802 target nrom <netrom-hostname>
4804 target remote <netrom-hostname>:1235
4808 GDB now includes support for the Apple Macintosh, as a host only. It
4809 may be run as either an MPW tool or as a standalone application, and
4810 it can debug through the serial port. All the usual GDB commands are
4811 available, but to the target command, you must supply "serial" as the
4812 device type instead of "/dev/ttyXX". See mpw-README in the main
4813 directory for more information on how to build. The MPW configuration
4814 scripts */mpw-config.in support only a few targets, and only the
4815 mips-idt-ecoff target has been tested.
4819 GDB configuration now uses autoconf. This is not user-visible,
4820 but does simplify configuration and building.
4824 GDB now supports hpux10.
4826 *** Changes in GDB-4.14:
4828 * New native configurations
4830 x86 FreeBSD i[345]86-*-freebsd
4831 x86 NetBSD i[345]86-*-netbsd
4832 NS32k NetBSD ns32k-*-netbsd
4833 Sparc NetBSD sparc-*-netbsd
4837 A29K VxWorks a29k-*-vxworks
4838 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4839 CPU32 EST-300 emulator m68*-*-est*
4840 PowerPC ELF powerpc-*-elf
4843 * Alpha OSF/1 support for procfs
4845 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4846 possible to attach to running processes. As the mounting of the /proc
4847 filesystem is optional on the Alpha, GDB automatically determines
4848 the availability of /proc during startup. This can lead to problems
4849 if /proc is unmounted after GDB has been started.
4851 * Arguments to user-defined commands
4853 User commands may accept up to 10 arguments separated by whitespace.
4854 Arguments are accessed within the user command via $arg0..$arg9. A
4857 print $arg0 + $arg1 + $arg2
4859 To execute the command use:
4862 Defines the command "adder" which prints the sum of its three arguments.
4863 Note the arguments are text substitutions, so they may reference variables,
4864 use complex expressions, or even perform inferior function calls.
4866 * New `if' and `while' commands
4868 This makes it possible to write more sophisticated user-defined
4869 commands. Both commands take a single argument, which is the
4870 expression to evaluate, and must be followed by the commands to
4871 execute, one per line, if the expression is nonzero, the list being
4872 terminated by the word `end'. The `if' command list may include an
4873 `else' word, which causes the following commands to be executed only
4874 if the expression is zero.
4876 * Fortran source language mode
4878 GDB now includes partial support for Fortran 77. It will recognize
4879 Fortran programs and can evaluate a subset of Fortran expressions, but
4880 variables and functions may not be handled correctly. GDB will work
4881 with G77, but does not yet know much about symbols emitted by other
4884 * Better HPUX support
4886 Most debugging facilities now work on dynamic executables for HPPAs
4887 running hpux9 or later. You can attach to running dynamically linked
4888 processes, but by default the dynamic libraries will be read-only, so
4889 for instance you won't be able to put breakpoints in them. To change
4890 that behavior do the following before running the program:
4896 This will cause the libraries to be mapped private and read-write.
4897 To revert to the normal behavior, do this:
4903 You cannot set breakpoints or examine data in the library until after
4904 the library is loaded if the function/data symbols do not have
4907 GDB can now also read debug symbols produced by the HP C compiler on
4908 HPPAs (sorry, no C++, Fortran or 68k support).
4910 * Target byte order now dynamically selectable
4912 You can choose which byte order to use with a target system, via the
4913 commands "set endian big" and "set endian little", and you can see the
4914 current setting by using "show endian". You can also give the command
4915 "set endian auto", in which case GDB will use the byte order
4916 associated with the executable. Currently, only embedded MIPS
4917 configurations support dynamic selection of target byte order.
4919 * New DOS host serial code
4921 This version uses DPMI interrupts to handle buffered I/O, so you
4922 no longer need to run asynctsr when debugging boards connected to
4925 *** Changes in GDB-4.13:
4927 * New "complete" command
4929 This lists all the possible completions for the rest of the line, if it
4930 were to be given as a command itself. This is intended for use by emacs.
4932 * Trailing space optional in prompt
4934 "set prompt" no longer adds a space for you after the prompt you set. This
4935 allows you to set a prompt which ends in a space or one that does not.
4937 * Breakpoint hit counts
4939 "info break" now displays a count of the number of times the breakpoint
4940 has been hit. This is especially useful in conjunction with "ignore"; you
4941 can ignore a large number of breakpoint hits, look at the breakpoint info
4942 to see how many times the breakpoint was hit, then run again, ignoring one
4943 less than that number, and this will get you quickly to the last hit of
4946 * Ability to stop printing at NULL character
4948 "set print null-stop" will cause GDB to stop printing the characters of
4949 an array when the first NULL is encountered. This is useful when large
4950 arrays actually contain only short strings.
4952 * Shared library breakpoints
4954 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4955 breakpoints in shared libraries before the executable is run.
4957 * Hardware watchpoints
4959 There is a new hardware breakpoint for the watch command for sparclite
4960 targets. See gdb/sparclite/hw_breakpoint.note.
4962 Hardware watchpoints are also now supported under GNU/Linux.
4966 Annotations have been added. These are for use with graphical interfaces,
4967 and are still experimental. Currently only gdba.el uses these.
4969 * Improved Irix 5 support
4971 GDB now works properly with Irix 5.2.
4973 * Improved HPPA support
4975 GDB now works properly with the latest GCC and GAS.
4977 * New native configurations
4979 Sequent PTX4 i[34]86-sequent-ptx4
4980 HPPA running OSF/1 hppa*-*-osf*
4981 Atari TT running SVR4 m68*-*-sysv4*
4982 RS/6000 LynxOS rs6000-*-lynxos*
4986 OS/9000 i[34]86-*-os9k
4987 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4990 * Hitachi SH7000 and E7000-PC ICE support
4992 There is now support for communicating with the Hitachi E7000-PC ICE.
4993 This is available automatically when GDB is configured for the SH.
4997 As usual, a variety of small fixes and improvements, both generic
4998 and configuration-specific. See the ChangeLog for more detail.
5000 *** Changes in GDB-4.12:
5002 * Irix 5 is now supported
5006 GDB-4.12 on the HPPA has a number of changes which make it unable
5007 to debug the output from the currently released versions of GCC and
5008 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5009 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5010 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5013 *** Changes in GDB-4.11:
5015 * User visible changes:
5019 The "set remotedebug" option is now consistent between the mips remote
5020 target, remote targets using the gdb-specific protocol, UDI (AMD's
5021 debug protocol for the 29k) and the 88k bug monitor. It is now an
5022 integer specifying a debug level (normally 0 or 1, but 2 means more
5023 debugging info for the mips target).
5025 * DEC Alpha native support
5027 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5028 debug info, but GDB works fairly well with the DEC compiler and should
5029 work with a future GCC release. See the README file for a few
5030 Alpha-specific notes.
5032 * Preliminary thread implementation
5034 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5036 * LynxOS native and target support for 386
5038 This release has been hosted on LynxOS 2.2, and also can be configured
5039 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5042 * Improvements in C++ mangling/demangling.
5044 This release has much better g++ debugging, specifically in name
5045 mangling/demangling, virtual function calls, print virtual table,
5046 call methods, ...etc.
5048 *** Changes in GDB-4.10:
5050 * User visible changes:
5052 Remote debugging using the GDB-specific (`target remote') protocol now
5053 supports the `load' command. This is only useful if you have some
5054 other way of getting the stub to the target system, and you can put it
5055 somewhere in memory where it won't get clobbered by the download.
5057 Filename completion now works.
5059 When run under emacs mode, the "info line" command now causes the
5060 arrow to point to the line specified. Also, "info line" prints
5061 addresses in symbolic form (as well as hex).
5063 All vxworks based targets now support a user settable option, called
5064 vxworks-timeout. This option represents the number of seconds gdb
5065 should wait for responses to rpc's. You might want to use this if
5066 your vxworks target is, perhaps, a slow software simulator or happens
5067 to be on the far side of a thin network line.
5071 This release contains support for using a DEC alpha as a GDB host for
5072 cross debugging. Native alpha debugging is not supported yet.
5075 *** Changes in GDB-4.9:
5079 This is the first GDB release which is accompanied by a matching testsuite.
5080 The testsuite requires installation of dejagnu, which should be available
5081 via ftp from most sites that carry GNU software.
5085 'Cfront' style demangling has had its name changed to 'ARM' style, to
5086 emphasize that it was written from the specifications in the C++ Annotated
5087 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5088 disclaimers, it still generated too much confusion with users attempting to
5089 use gdb with AT&T cfront.
5093 GDB now uses a standard remote interface to a simulator library.
5094 So far, the library contains simulators for the Zilog Z8001/2, the
5095 Hitachi H8/300, H8/500 and Super-H.
5097 * New targets supported
5099 H8/300 simulator h8300-hitachi-hms or h8300hms
5100 H8/500 simulator h8500-hitachi-hms or h8500hms
5101 SH simulator sh-hitachi-hms or sh
5102 Z8000 simulator z8k-zilog-none or z8ksim
5103 IDT MIPS board over serial line mips-idt-ecoff
5105 Cross-debugging to GO32 targets is supported. It requires a custom
5106 version of the i386-stub.c module which is integrated with the
5107 GO32 memory extender.
5109 * New remote protocols
5111 MIPS remote debugging protocol.
5113 * New source languages supported
5115 This version includes preliminary support for Chill, a Pascal like language
5116 used by telecommunications companies. Chill support is also being integrated
5117 into the GNU compiler, but we don't know when it will be publically available.
5120 *** Changes in GDB-4.8:
5122 * HP Precision Architecture supported
5124 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5125 version of this support was available as a set of patches from the
5126 University of Utah. GDB does not support debugging of programs
5127 compiled with the HP compiler, because HP will not document their file
5128 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5129 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5131 Many problems in the preliminary version have been fixed.
5133 * Faster and better demangling
5135 We have improved template demangling and fixed numerous bugs in the GNU style
5136 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5137 character types (wchar_t) are now supported. Demangling of each symbol is now
5138 only done once, and is cached when the symbol table for a file is read in.
5139 This results in a small increase in memory usage for C programs, a moderate
5140 increase in memory usage for C++ programs, and a fantastic speedup in
5143 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5144 from the specifications in the Annotated Reference Manual, which AT&T's
5145 compiler does not actually implement.
5147 * G++ multiple inheritance compiler problem
5149 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5150 inheritance lattices was reworked to properly discover ambiguities. We
5151 recently found an example which causes this new algorithm to fail in a
5152 very subtle way, producing bad debug information for those classes.
5153 The file 'gcc.patch' (in this directory) can be applied to gcc to
5154 circumvent the problem. A future GCC release will contain a complete
5157 The previous G++ debug info problem (mentioned below for the gdb-4.7
5158 release) is fixed in gcc version 2.3.2.
5160 * Improved configure script
5162 The `configure' script will now attempt to guess your system type if
5163 you don't supply a host system type. The old scheme of supplying a
5164 host system triplet is preferable over using this. All the magic is
5165 done in the new `config.guess' script. Examine it for details.
5167 We have also brought our configure script much more in line with the FSF's
5168 version. It now supports the --with-xxx options. In particular,
5169 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5170 The resulting GDB will not be able to read arbitrary object file formats --
5171 only the format ``expected'' to be used on the configured target system.
5172 We hope to make this the default in a future release.
5174 * Documentation improvements
5176 There's new internal documentation on how to modify GDB, and how to
5177 produce clean changes to the code. We implore people to read it
5178 before submitting changes.
5180 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5181 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5182 `info' files are also provided. To build `info' files from scratch,
5183 you will need the latest `makeinfo' release, which will be available in
5184 a future texinfo-X.Y release.
5186 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5187 We're not sure exactly which versions have this problem, but it has
5188 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5189 or better. If that isn't possible, there is a patch in
5190 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5191 around this problem.
5195 GDB now supports array constants that can be used in expressions typed in by
5196 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5197 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5200 The new directory `gdb/sparclite' contains a program that demonstrates
5201 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5203 * New native hosts supported
5205 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5206 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5208 * New targets supported
5210 AMD 29k family via UDI a29k-amd-udi or udi29k
5212 * New file formats supported
5214 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5215 HPUX core files, and SCO 3.2v2 core files.
5219 Attaching to processes now works again; thanks for the many bug reports.
5221 We have also stomped on a bunch of core dumps caused by
5222 printf_filtered("%s") problems.
5224 We eliminated a copyright problem on the rpc and ptrace header files
5225 for VxWorks, which was discovered at the last minute during the 4.7
5226 release. You should now be able to build a VxWorks GDB.
5228 You can now interrupt gdb while an attached process is running. This
5229 will cause the attached process to stop, and give control back to GDB.
5231 We fixed problems caused by using too many file descriptors
5232 for reading symbols from object files and libraries. This was
5233 especially a problem for programs that used many (~100) shared
5236 The `step' command now only enters a subroutine if there is line number
5237 information for the subroutine. Otherwise it acts like the `next'
5238 command. Previously, `step' would enter subroutines if there was
5239 any debugging information about the routine. This avoids problems
5240 when using `cc -g1' on MIPS machines.
5242 * Internal improvements
5244 GDB's internal interfaces have been improved to make it easier to support
5245 debugging of multiple languages in the future.
5247 GDB now uses a common structure for symbol information internally.
5248 Minimal symbols (derived from linkage symbols in object files), partial
5249 symbols (from a quick scan of debug information), and full symbols
5250 contain a common subset of information, making it easier to write
5251 shared code that handles any of them.
5253 * New command line options
5255 We now accept --silent as an alias for --quiet.
5259 The memory-mapped-malloc library is now licensed under the GNU Library
5260 General Public License.
5262 *** Changes in GDB-4.7:
5264 * Host/native/target split
5266 GDB has had some major internal surgery to untangle the support for
5267 hosts and remote targets. Now, when you configure GDB for a remote
5268 target, it will no longer load in all of the support for debugging
5269 local programs on the host. When fully completed and tested, this will
5270 ensure that arbitrary host/target combinations are possible.
5272 The primary conceptual shift is to separate the non-portable code in
5273 GDB into three categories. Host specific code is required any time GDB
5274 is compiled on that host, regardless of the target. Target specific
5275 code relates to the peculiarities of the target, but can be compiled on
5276 any host. Native specific code is everything else: it can only be
5277 built when the host and target are the same system. Child process
5278 handling and core file support are two common `native' examples.
5280 GDB's use of /proc for controlling Unix child processes is now cleaner.
5281 It has been split out into a single module under the `target_ops' vector,
5282 plus two native-dependent functions for each system that uses /proc.
5284 * New hosts supported
5286 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5287 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5288 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5290 * New targets supported
5292 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5293 68030 and CPU32 m68030-*-*, m68332-*-*
5295 * New native hosts supported
5297 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5298 (386bsd is not well tested yet)
5299 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5301 * New file formats supported
5303 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5304 supports reading of `a.out.adobe' object files, which are an a.out
5305 format extended with minimal information about multiple sections.
5309 `show copying' is the same as the old `info copying'.
5310 `show warranty' is the same as `info warrantee'.
5311 These were renamed for consistency. The old commands continue to work.
5313 `info handle' is a new alias for `info signals'.
5315 You can now define pre-command hooks, which attach arbitrary command
5316 scripts to any command. The commands in the hook will be executed
5317 prior to the user's command. You can also create a hook which will be
5318 executed whenever the program stops. See gdb.texinfo.
5322 We now deal with Cfront style name mangling, and can even extract type
5323 info from mangled symbols. GDB can automatically figure out which
5324 symbol mangling style your C++ compiler uses.
5326 Calling of methods and virtual functions has been improved as well.
5330 The crash that occured when debugging Sun Ansi-C compiled binaries is
5331 fixed. This was due to mishandling of the extra N_SO stabs output
5334 We also finally got Ultrix 4.2 running in house, and fixed core file
5335 support, with help from a dozen people on the net.
5337 John M. Farrell discovered that the reason that single-stepping was so
5338 slow on all of the Mips based platforms (primarily SGI and DEC) was
5339 that we were trying to demangle and lookup a symbol used for internal
5340 purposes on every instruction that was being stepped through. Changing
5341 the name of that symbol so that it couldn't be mistaken for a C++
5342 mangled symbol sped things up a great deal.
5344 Rich Pixley sped up symbol lookups in general by getting much smarter
5345 about when C++ symbol mangling is necessary. This should make symbol
5346 completion (TAB on the command line) much faster. It's not as fast as
5347 we'd like, but it's significantly faster than gdb-4.6.
5351 A new user controllable variable 'call_scratch_address' can
5352 specify the location of a scratch area to be used when GDB
5353 calls a function in the target. This is necessary because the
5354 usual method of putting the scratch area on the stack does not work
5355 in systems that have separate instruction and data spaces.
5357 We integrated changes to support the 29k UDI (Universal Debugger
5358 Interface), but discovered at the last minute that we didn't have all
5359 of the appropriate copyright paperwork. We are working with AMD to
5360 resolve this, and hope to have it available soon.
5364 We have sped up the remote serial line protocol, especially for targets
5365 with lots of registers. It now supports a new `expedited status' ('T')
5366 message which can be used in place of the existing 'S' status message.
5367 This allows the remote stub to send only the registers that GDB
5368 needs to make a quick decision about single-stepping or conditional
5369 breakpoints, eliminating the need to fetch the entire register set for
5370 each instruction being stepped through.
5372 The GDB remote serial protocol now implements a write-through cache for
5373 registers, only re-reading the registers if the target has run.
5375 There is also a new remote serial stub for SPARC processors. You can
5376 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5377 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5378 processor with a serial port.
5382 Configure.in files have become much easier to read and modify. A new
5383 `table driven' format makes it more obvious what configurations are
5384 supported, and what files each one uses.
5388 There is a new opcodes library which will eventually contain all of the
5389 disassembly routines and opcode tables. At present, it only contains
5390 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5391 disassembler (binutils/objdump) to share these routines.
5393 The libiberty library is now copylefted under the GNU Library General
5394 Public License. This allows more liberal use, and was done so libg++
5395 can use it. This makes no difference to GDB, since the Library License
5396 grants all the rights from the General Public License.
5400 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5401 reference to the stabs symbol info used by the debugger. It is (as far
5402 as we know) the only published document on this fascinating topic. We
5403 encourage you to read it, compare it to the stabs information on your
5404 system, and send improvements on the document in general (to
5405 bug-gdb@prep.ai.mit.edu).
5407 And, of course, many bugs have been fixed.
5410 *** Changes in GDB-4.6:
5412 * Better support for C++ function names
5414 GDB now accepts as input the "demangled form" of C++ overloaded function
5415 names and member function names, and can do command completion on such names
5416 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5417 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5418 Make use of command completion, it is your friend.
5420 GDB also now accepts a variety of C++ mangled symbol formats. They are
5421 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5422 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5423 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5424 for the list of formats.
5426 * G++ symbol mangling problem
5428 Recent versions of gcc have a bug in how they emit debugging information for
5429 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5430 directory) can be applied to gcc to fix the problem. Alternatively, if you
5431 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5432 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5433 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5436 * New 'maintenance' command
5438 All of the commands related to hacking GDB internals have been moved out of
5439 the main command set, and now live behind the 'maintenance' command. This
5440 can also be abbreviated as 'mt'. The following changes were made:
5442 dump-me -> maintenance dump-me
5443 info all-breakpoints -> maintenance info breakpoints
5444 printmsyms -> maintenance print msyms
5445 printobjfiles -> maintenance print objfiles
5446 printpsyms -> maintenance print psymbols
5447 printsyms -> maintenance print symbols
5449 The following commands are new:
5451 maintenance demangle Call internal GDB demangler routine to
5452 demangle a C++ link name and prints the result.
5453 maintenance print type Print a type chain for a given symbol
5455 * Change to .gdbinit file processing
5457 We now read the $HOME/.gdbinit file before processing the argv arguments
5458 (e.g. reading symbol files or core files). This allows global parameters to
5459 be set, which will apply during the symbol reading. The ./.gdbinit is still
5460 read after argv processing.
5462 * New hosts supported
5464 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5466 GNU/Linux support i386-unknown-linux or linux
5468 We are also including code to support the HP/PA running BSD and HPUX. This
5469 is almost guaranteed not to work, as we didn't have time to test or build it
5470 for this release. We are including it so that the more adventurous (or
5471 masochistic) of you can play with it. We also had major problems with the
5472 fact that the compiler that we got from HP doesn't support the -g option.
5475 * New targets supported
5477 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5479 * More smarts about finding #include files
5481 GDB now remembers the compilation directory for all include files, and for
5482 all files from which C is generated (like yacc and lex sources). This
5483 greatly improves GDB's ability to find yacc/lex sources, and include files,
5484 especially if you are debugging your program from a directory different from
5485 the one that contains your sources.
5487 We also fixed a bug which caused difficulty with listing and setting
5488 breakpoints in include files which contain C code. (In the past, you had to
5489 try twice in order to list an include file that you hadn't looked at before.)
5491 * Interesting infernals change
5493 GDB now deals with arbitrary numbers of sections, where the symbols for each
5494 section must be relocated relative to that section's landing place in the
5495 target's address space. This work was needed to support ELF with embedded
5496 stabs used by Solaris-2.0.
5498 * Bug fixes (of course!)
5500 There have been loads of fixes for the following things:
5501 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5502 i960, stabs, DOS(GO32), procfs, etc...
5504 See the ChangeLog for details.
5506 *** Changes in GDB-4.5:
5508 * New machines supported (host and target)
5510 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5512 SGI Irix-4.x mips-sgi-irix4 or iris4
5514 * New malloc package
5516 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5517 Mmalloc is capable of handling mutiple heaps of memory. It is also
5518 capable of saving a heap to a file, and then mapping it back in later.
5519 This can be used to greatly speedup the startup of GDB by using a
5520 pre-parsed symbol table which lives in a mmalloc managed heap. For
5521 more details, please read mmalloc/mmalloc.texi.
5525 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5526 'help info proc' for details.
5528 * MIPS ecoff symbol table format
5530 The code that reads MIPS symbol table format is now supported on all hosts.
5531 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5534 * File name changes for MS-DOS
5536 Many files in the config directories have been renamed to make it easier to
5537 support GDB on MS-DOSe systems (which have very restrictive file name
5538 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5539 environment) is close to working but has some remaining problems. Note
5540 that debugging of DOS programs is not supported, due to limitations
5541 in the ``operating system'', but it can be used to host cross-debugging.
5543 * Cross byte order fixes
5545 Many fixes have been made to support cross debugging of Sparc and MIPS
5546 targets from hosts whose byte order differs.
5548 * New -mapped and -readnow options
5550 If memory-mapped files are available on your system through the 'mmap'
5551 system call, you can use the -mapped option on the `file' or
5552 `symbol-file' commands to cause GDB to write the symbols from your
5553 program into a reusable file. If the program you are debugging is
5554 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5555 Future GDB debugging sessions will notice the presence of this file,
5556 and will quickly map in symbol information from it, rather than reading
5557 the symbol table from the executable program. Using the '-mapped'
5558 option in a GDB `file' or `symbol-file' command has the same effect as
5559 starting GDB with the '-mapped' command-line option.
5561 You can cause GDB to read the entire symbol table immediately by using
5562 the '-readnow' option with any of the commands that load symbol table
5563 information (or on the GDB command line). This makes the command
5564 slower, but makes future operations faster.
5566 The -mapped and -readnow options are typically combined in order to
5567 build a `fred.syms' file that contains complete symbol information.
5568 A simple GDB invocation to do nothing but build a `.syms' file for future
5571 gdb -batch -nx -mapped -readnow programname
5573 The `.syms' file is specific to the host machine on which GDB is run.
5574 It holds an exact image of GDB's internal symbol table. It cannot be
5575 shared across multiple host platforms.
5577 * longjmp() handling
5579 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5580 siglongjmp() without losing control. This feature has not yet been ported to
5581 all systems. It currently works on many 386 platforms, all MIPS-based
5582 platforms (SGI, DECstation, etc), and Sun3/4.
5586 Preliminary work has been put in to support the new Solaris OS from Sun. At
5587 this time, it can control and debug processes, but it is not capable of
5592 As always, many many bug fixes. The major areas were with g++, and mipsread.
5593 People using the MIPS-based platforms should experience fewer mysterious
5594 crashes and trashed symbol tables.
5596 *** Changes in GDB-4.4:
5598 * New machines supported (host and target)
5600 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5602 BSD Reno on Vax vax-dec-bsd
5603 Ultrix on Vax vax-dec-ultrix
5605 * New machines supported (target)
5607 AMD 29000 embedded, using EBMON a29k-none-none
5611 GDB continues to improve its handling of C++. `References' work better.
5612 The demangler has also been improved, and now deals with symbols mangled as
5613 per the Annotated C++ Reference Guide.
5615 GDB also now handles `stabs' symbol information embedded in MIPS
5616 `ecoff' symbol tables. Since the ecoff format was not easily
5617 extensible to handle new languages such as C++, this appeared to be a
5618 good way to put C++ debugging info into MIPS binaries. This option
5619 will be supported in the GNU C compiler, version 2, when it is
5622 * New features for SVR4
5624 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5625 shared libraries. Debugging dynamically linked programs should present
5626 only minor differences from debugging statically linked programs.
5628 The `info proc' command will print out information about any process
5629 on an SVR4 system (including the one you are debugging). At the moment,
5630 it prints the address mappings of the process.
5632 If you bring up GDB on another SVR4 system, please send mail to
5633 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5635 * Better dynamic linking support in SunOS
5637 Reading symbols from shared libraries which contain debugging symbols
5638 now works properly. However, there remain issues such as automatic
5639 skipping of `transfer vector' code during function calls, which
5640 make it harder to debug code in a shared library, than to debug the
5641 same code linked statically.
5645 GDB is now using the latest `getopt' routines from the FSF. This
5646 version accepts the -- prefix for options with long names. GDB will
5647 continue to accept the old forms (-option and +option) as well.
5648 Various single letter abbreviations for options have been explicity
5649 added to the option table so that they won't get overshadowed in the
5650 future by other options that begin with the same letter.
5654 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5655 Many assorted bugs have been handled. Many more remain to be handled.
5656 See the various ChangeLog files (primarily in gdb and bfd) for details.
5659 *** Changes in GDB-4.3:
5661 * New machines supported (host and target)
5663 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5664 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5665 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5667 * Almost SCO Unix support
5669 We had hoped to support:
5670 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5671 (except for core file support), but we discovered very late in the release
5672 that it has problems with process groups that render gdb unusable. Sorry
5673 about that. I encourage people to fix it and post the fixes.
5675 * Preliminary ELF and DWARF support
5677 GDB can read ELF object files on System V Release 4, and can handle
5678 debugging records for C, in DWARF format, in ELF files. This support
5679 is preliminary. If you bring up GDB on another SVR4 system, please
5680 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5685 GDB now uses the latest `readline' library. One user-visible change
5686 is that two tabs will list possible command completions, which previously
5687 required typing M-? (meta-question mark, or ESC ?).
5691 The `stepi' bug that many of you noticed has been squashed.
5692 Many bugs in C++ have been handled. Many more remain to be handled.
5693 See the various ChangeLog files (primarily in gdb and bfd) for details.
5695 * State of the MIPS world (in case you wondered):
5697 GDB can understand the symbol tables emitted by the compilers
5698 supplied by most vendors of MIPS-based machines, including DEC. These
5699 symbol tables are in a format that essentially nobody else uses.
5701 Some versions of gcc come with an assembler post-processor called
5702 mips-tfile. This program is required if you want to do source-level
5703 debugging of gcc-compiled programs. I believe FSF does not ship
5704 mips-tfile with gcc version 1, but it will eventually come with gcc
5707 Debugging of g++ output remains a problem. g++ version 1.xx does not
5708 really support it at all. (If you're lucky, you should be able to get
5709 line numbers and stack traces to work, but no parameters or local
5710 variables.) With some work it should be possible to improve the
5713 When gcc version 2 is released, you will have somewhat better luck.
5714 However, even then you will get confusing results for inheritance and
5717 We will eventually provide full debugging of g++ output on
5718 DECstations. This will probably involve some kind of stabs-in-ecoff
5719 encapulation, but the details have not been worked out yet.
5722 *** Changes in GDB-4.2:
5724 * Improved configuration
5726 Only one copy of `configure' exists now, and it is not self-modifying.
5727 Porting BFD is simpler.
5731 The `step' and `next' commands now only stop at the first instruction
5732 of a source line. This prevents the multiple stops that used to occur
5733 in switch statements, for-loops, etc. `Step' continues to stop if a
5734 function that has debugging information is called within the line.
5738 Lots of small bugs fixed. More remain.
5740 * New host supported (not target)
5742 Intel 386 PC clone running Mach i386-none-mach
5745 *** Changes in GDB-4.1:
5747 * Multiple source language support
5749 GDB now has internal scaffolding to handle several source languages.
5750 It determines the type of each source file from its filename extension,
5751 and will switch expression parsing and number formatting to match the
5752 language of the function in the currently selected stack frame.
5753 You can also specifically set the language to be used, with
5754 `set language c' or `set language modula-2'.
5758 GDB now has preliminary support for the GNU Modula-2 compiler,
5759 currently under development at the State University of New York at
5760 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5761 continue through the fall of 1991 and into 1992.
5763 Other Modula-2 compilers are currently not supported, and attempting to
5764 debug programs compiled with them will likely result in an error as the
5765 symbol table is read. Feel free to work on it, though!
5767 There are hooks in GDB for strict type checking and range checking,
5768 in the `Modula-2 philosophy', but they do not currently work.
5772 GDB can now write to executable and core files (e.g. patch
5773 a variable's value). You must turn this switch on, specify
5774 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5775 by assigning a new value to a variable. Modifications take
5778 * Automatic SunOS shared library reading
5780 When you run your program, GDB automatically determines where its
5781 shared libraries (if any) have been loaded, and reads their symbols.
5782 The `share' command is no longer needed. This also works when
5783 examining core files.
5787 You can specify the number of lines that the `list' command shows.
5790 * New machines supported (host and target)
5792 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5793 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5794 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5796 * New hosts supported (not targets)
5798 IBM RT/PC: romp-ibm-aix or rtpc
5800 * New targets supported (not hosts)
5802 AMD 29000 embedded with COFF a29k-none-coff
5803 AMD 29000 embedded with a.out a29k-none-aout
5804 Ultracomputer remote kernel debug a29k-nyu-kern
5806 * New remote interfaces
5812 *** Changes in GDB-4.0:
5816 Wide output is wrapped at good places to make the output more readable.
5818 Gdb now supports cross-debugging from a host machine of one type to a
5819 target machine of another type. Communication with the target system
5820 is over serial lines. The ``target'' command handles connecting to the
5821 remote system; the ``load'' command will download a program into the
5822 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5823 also supports debugging of realtime processes running under VxWorks,
5824 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5825 stub on the target system.
5827 New CPUs supported include the AMD 29000 and Intel 960.
5829 GDB now reads object files and symbol tables via a ``binary file''
5830 library, which allows a single copy of GDB to debug programs of multiple
5831 object file types such as a.out and coff.
5833 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5834 refcard.dvi and refcard.ps are available to format it).
5837 * Control-Variable user interface simplified
5839 All variables that control the operation of the debugger can be set
5840 by the ``set'' command, and displayed by the ``show'' command.
5842 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5843 ``Show prompt'' produces the response:
5844 Gdb's prompt is new-gdb=>.
5846 What follows are the NEW set commands. The command ``help set'' will
5847 print a complete list of old and new set commands. ``help set FOO''
5848 will give a longer description of the variable FOO. ``show'' will show
5849 all of the variable descriptions and their current settings.
5851 confirm on/off: Enables warning questions for operations that are
5852 hard to recover from, e.g. rerunning the program while
5853 it is already running. Default is ON.
5855 editing on/off: Enables EMACS style command line editing
5856 of input. Previous lines can be recalled with
5857 control-P, the current line can be edited with control-B,
5858 you can search for commands with control-R, etc.
5861 history filename NAME: NAME is where the gdb command history
5862 will be stored. The default is .gdb_history,
5863 or the value of the environment variable
5866 history size N: The size, in commands, of the command history. The
5867 default is 256, or the value of the environment variable
5870 history save on/off: If this value is set to ON, the history file will
5871 be saved after exiting gdb. If set to OFF, the
5872 file will not be saved. The default is OFF.
5874 history expansion on/off: If this value is set to ON, then csh-like
5875 history expansion will be performed on
5876 command line input. The default is OFF.
5878 radix N: Sets the default radix for input and output. It can be set
5879 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5880 in the current radix, so "set radix 10" is always a no-op.
5882 height N: This integer value is the number of lines on a page. Default
5883 is 24, the current `stty rows'' setting, or the ``li#''
5884 setting from the termcap entry matching the environment
5887 width N: This integer value is the number of characters on a line.
5888 Default is 80, the current `stty cols'' setting, or the ``co#''
5889 setting from the termcap entry matching the environment
5892 Note: ``set screensize'' is obsolete. Use ``set height'' and
5893 ``set width'' instead.
5895 print address on/off: Print memory addresses in various command displays,
5896 such as stack traces and structure values. Gdb looks
5897 more ``symbolic'' if you turn this off; it looks more
5898 ``machine level'' with it on. Default is ON.
5900 print array on/off: Prettyprint arrays. New convenient format! Default
5903 print demangle on/off: Print C++ symbols in "source" form if on,
5906 print asm-demangle on/off: Same, for assembler level printouts
5909 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5912 * Support for Epoch Environment.
5914 The epoch environment is a version of Emacs v18 with windowing. One
5915 new command, ``inspect'', is identical to ``print'', except that if you
5916 are running in the epoch environment, the value is printed in its own
5920 * Support for Shared Libraries
5922 GDB can now debug programs and core files that use SunOS shared libraries.
5923 Symbols from a shared library cannot be referenced
5924 before the shared library has been linked with the program (this
5925 happens after you type ``run'' and before the function main() is entered).
5926 At any time after this linking (including when examining core files
5927 from dynamically linked programs), gdb reads the symbols from each
5928 shared library when you type the ``sharedlibrary'' command.
5929 It can be abbreviated ``share''.
5931 sharedlibrary REGEXP: Load shared object library symbols for files
5932 matching a unix regular expression. No argument
5933 indicates to load symbols for all shared libraries.
5935 info sharedlibrary: Status of loaded shared libraries.
5940 A watchpoint stops execution of a program whenever the value of an
5941 expression changes. Checking for this slows down execution
5942 tremendously whenever you are in the scope of the expression, but is
5943 quite useful for catching tough ``bit-spreader'' or pointer misuse
5944 problems. Some machines such as the 386 have hardware for doing this
5945 more quickly, and future versions of gdb will use this hardware.
5947 watch EXP: Set a watchpoint (breakpoint) for an expression.
5949 info watchpoints: Information about your watchpoints.
5951 delete N: Deletes watchpoint number N (same as breakpoints).
5952 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5953 enable N: Re-enables watchpoint number N (same as breakpoints).
5956 * C++ multiple inheritance
5958 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5961 * C++ exception handling
5963 Gdb now supports limited C++ exception handling. Besides the existing
5964 ability to breakpoint on an exception handler, gdb can breakpoint on
5965 the raising of an exception (before the stack is peeled back to the
5968 catch FOO: If there is a FOO exception handler in the dynamic scope,
5969 set a breakpoint to catch exceptions which may be raised there.
5970 Multiple exceptions (``catch foo bar baz'') may be caught.
5972 info catch: Lists all exceptions which may be caught in the
5973 current stack frame.
5976 * Minor command changes
5978 The command ``call func (arg, arg, ...)'' now acts like the print
5979 command, except it does not print or save a value if the function's result
5980 is void. This is similar to dbx usage.
5982 The ``up'' and ``down'' commands now always print the frame they end up
5983 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5984 frames without printing.
5986 * New directory command
5988 'dir' now adds directories to the FRONT of the source search path.
5989 The path starts off empty. Source files that contain debug information
5990 about the directory in which they were compiled can be found even
5991 with an empty path; Sun CC and GCC include this information. If GDB can't
5992 find your source file in the current directory, type "dir .".
5994 * Configuring GDB for compilation
5996 For normal use, type ``./configure host''. See README or gdb.texinfo
5999 GDB now handles cross debugging. If you are remotely debugging between
6000 two different machines, type ``./configure host -target=targ''.
6001 Host is the machine where GDB will run; targ is the machine
6002 where the program that you are debugging will run.