1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.8
6 * GDB now supports hardware watchpoints on x86 GNU Hurd.
10 ** You can now access frame registers from Python scripts.
11 ** New attribute 'producer' for gdb.Symtab objects.
12 ** gdb.Objfile objects have a new attribute "progspace",
13 which is the gdb.Progspace object of the containing program space.
14 ** gdb.Objfile objects have a new attribute "owner".
15 ** gdb.Objfile objects have a new attribute "build_id",
16 which is the build ID generated when the file was built.
17 ** gdb.Objfile objects have a new method "add_separate_debug_file".
18 ** A new event "gdb.clear_objfiles" has been added, triggered when
19 selecting a new file to debug.
20 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
21 ** New function gdb.lookup_objfile.
23 New events which are triggered when GDB modifies the state of the
26 ** gdb.events.inferior_call_pre: Function call is about to be made.
27 ** gdb.events.inferior_call_post: Function call has just been made.
28 ** gdb.events.memory_changed: A memory location has been altered.
29 ** gdb.events.register_changed: A register has been altered.
31 * New Python-based convenience functions:
33 ** $_caller_is(name [, number_of_frames])
34 ** $_caller_matches(regexp [, number_of_frames])
35 ** $_any_caller_is(name [, number_of_frames])
36 ** $_any_caller_matches(regexp [, number_of_frames])
38 * GDB now supports the compilation and injection of source code into
39 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
40 to compile the source code to object code, and if successful, inject
41 and execute that code within the current context of the inferior.
42 Currently the C language is supported. The commands used to
43 interface with this new feature are:
45 compile code [-raw|-r] [--] [source code]
46 compile file [-raw|-r] filename
50 queue-signal signal-name-or-number
51 Queue a signal to be delivered to the thread when it is resumed.
53 add-auto-load-scripts-directory directory
54 Add entries to the list of directories from which to load auto-loaded
57 maint print user-registers
58 List all currently available "user" registers.
60 maint print symbol-cache
61 Print the contents of the symbol cache.
63 maint print symbol-cache-statistics
64 Print statistics of symbol cache usage.
66 maint flush-symbol-cache
67 Flush the contents of the symbol cache.
69 compile code [-r|-raw] [--] [source code]
70 Compile, inject, and execute in the inferior the executable object
71 code produced by compiling the provided source code.
73 compile file [-r|-raw] filename
74 Compile and inject into the inferior the executable object code
75 produced by compiling the source code stored in the filename
78 * On resume, GDB now always passes the signal the program had stopped
79 for to the thread the signal was sent to, even if the user changed
80 threads before resuming. Previously GDB would often (but not
81 always) deliver the signal to the thread that happens to be current
84 * Conversely, the "signal" command now consistently delivers the
85 requested signal to the current thread. GDB now asks for
86 confirmation if the program had stopped for a signal and the user
87 switched threads meanwhile.
89 * "breakpoint always-inserted" modes "off" and "auto" merged.
91 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
92 won't remove breakpoints from the target until all threads stop,
93 even in non-stop mode. The "auto" mode has been removed, and "off"
94 is now the default mode.
98 set debug symbol-lookup
99 show debug symbol-lookup
100 Control display of debugging info regarding symbol lookup.
102 maint set symbol-cache-size
103 maint show symbol-cache-size
104 Control the size of the symbol cache.
108 ** The -list-thread-groups command outputs an exit-code field for
109 inferiors that have exited.
113 MIPS SDE mips*-sde*-elf*
117 Support for these obsolete configurations has been removed.
119 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
120 SGI Irix-5.x mips-*-irix5*
121 SGI Irix-6.x mips-*-irix6*
122 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
123 VAX running Ultrix vax-*-ultrix*
125 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
126 and "assf"), have been removed. Use the "sharedlibrary" command, or
127 its alias "share", instead.
129 *** Changes in GDB 7.8
131 * New command line options
134 This is an alias for the --data-directory option.
136 * GDB supports printing and modifying of variable length automatic arrays
137 as specified in ISO C99.
139 * The ARM simulator now supports instruction level tracing
140 with or without disassembly.
144 GDB now has support for scripting using Guile. Whether this is
145 available is determined at configure time.
146 Guile version 2.0 or greater is required.
147 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
149 * New commands (for set/show, see "New options" below)
153 Invoke CODE by passing it to the Guile interpreter.
157 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
159 info auto-load guile-scripts [regexp]
160 Print the list of automatically loaded Guile scripts.
162 * The source command is now capable of sourcing Guile scripts.
163 This feature is dependent on the debugger being built with Guile support.
167 set print symbol-loading (off|brief|full)
168 show print symbol-loading
169 Control whether to print informational messages when loading symbol
170 information for a file. The default is "full", but when debugging
171 programs with large numbers of shared libraries the amount of output
174 set guile print-stack (none|message|full)
175 show guile print-stack
176 Show a stack trace when an error is encountered in a Guile script.
178 set auto-load guile-scripts (on|off)
179 show auto-load guile-scripts
180 Control auto-loading of Guile script files.
182 maint ada set ignore-descriptive-types (on|off)
183 maint ada show ignore-descriptive-types
184 Control whether the debugger should ignore descriptive types in Ada
185 programs. The default is not to ignore the descriptive types. See
186 the user manual for more details on descriptive types and the intended
187 usage of this option.
189 set auto-connect-native-target
191 Control whether GDB is allowed to automatically connect to the
192 native target for the run, attach, etc. commands when not connected
193 to any target yet. See also "target native" below.
195 set record btrace replay-memory-access (read-only|read-write)
196 show record btrace replay-memory-access
197 Control what memory accesses are allowed during replay.
199 maint set target-async (on|off)
200 maint show target-async
201 This controls whether GDB targets operate in synchronous or
202 asynchronous mode. Normally the default is asynchronous, if it is
203 available; but this can be changed to more easily debug problems
204 occurring only in synchronous mode.
206 set mi-async (on|off)
208 Control whether MI asynchronous mode is preferred. This supersedes
209 "set target-async" of previous GDB versions.
211 * "set target-async" is deprecated as a CLI option and is now an alias
212 for "set mi-async" (only puts MI into async mode).
214 * Background execution commands (e.g., "c&", "s&", etc.) are now
215 possible ``out of the box'' if the target supports them. Previously
216 the user would need to explicitly enable the possibility with the
217 "set target-async on" command.
219 * New features in the GDB remote stub, GDBserver
221 ** New option --debug-format=option1[,option2,...] allows one to add
222 additional text to each output. At present only timestamps
223 are supported: --debug-format=timestamps.
224 Timestamps can also be turned on with the
225 "monitor set debug-format timestamps" command from GDB.
227 * The 'record instruction-history' command now starts counting instructions
228 at one. This also affects the instruction ranges reported by the
229 'record function-call-history' command when given the /i modifier.
231 * The command 'record function-call-history' supports a new modifier '/c' to
232 indent the function names based on their call stack depth.
233 The fields for the '/i' and '/l' modifier have been reordered.
234 The source line range is now prefixed with 'at'.
235 The instruction range is now prefixed with 'inst'.
236 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
237 "record instruction-history" and "list" commands.
239 * The ranges given as arguments to the 'record function-call-history' and
240 'record instruction-history' commands are now inclusive.
242 * The btrace record target now supports the 'record goto' command.
243 For locations inside the execution trace, the back trace is computed
244 based on the information stored in the execution trace.
246 * The btrace record target supports limited reverse execution and replay.
247 The target does not record data and therefore does not allow reading
250 * The "catch syscall" command now works on s390*-linux* targets.
252 * The "compare-sections" command is no longer specific to target
253 remote. It now works with all targets.
255 * All native targets are now consistently called "native".
256 Consequently, the "target child", "target GNU", "target djgpp",
257 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
258 commands have been replaced with "target native". The QNX/NTO port
259 leaves the "procfs" target in place and adds a "native" target for
260 consistency with other ports. The impact on users should be minimal
261 as these commands previously either throwed an error, or were
262 no-ops. The target's name is visible in the output of the following
263 commands: "help target", "info target", "info files", "maint print
266 * The "target native" command now connects to the native target. This
267 can be used to launch native programs even when "set
268 auto-connect-native-target" is set to off.
270 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
272 * Support for Intel(R) AVX-512 registers on GNU/Linux.
273 Support displaying and modifying Intel(R) AVX-512 registers
274 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
278 qXfer:btrace:read's annex
279 The qXfer:btrace:read packet supports a new annex 'delta' to read
280 branch trace incrementally.
284 ** Valid Python operations on gdb.Value objects representing
285 structs/classes invoke the corresponding overloaded operators if
287 ** New `Xmethods' feature in the Python API. Xmethods are
288 additional methods or replacements for existing methods of a C++
289 class. This feature is useful for those cases where a method
290 defined in C++ source code could be inlined or optimized out by
291 the compiler, making it unavailable to GDB.
294 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
296 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
297 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
298 its alias "share", instead.
300 * The commands "set remotebaud" and "show remotebaud" are no longer
301 supported. Use "set serial baud" and "show serial baud" (respectively)
306 ** A new option "-gdb-set mi-async" replaces "-gdb-set
307 target-async". The latter is left as a deprecated alias of the
308 former for backward compatibility. If the target supports it,
309 CLI background execution commands are now always possible by
310 default, independently of whether the frontend stated a
311 preference for asynchronous execution with "-gdb-set mi-async".
312 Previously "-gdb-set target-async off" affected both MI execution
313 commands and CLI execution commands.
315 *** Changes in GDB 7.7
317 * Improved support for process record-replay and reverse debugging on
318 arm*-linux* targets. Support for thumb32 and syscall instruction
319 recording has been added.
321 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
323 * GDB now supports Fission DWP file format version 2.
324 http://gcc.gnu.org/wiki/DebugFission
326 * New convenience function "$_isvoid", to check whether an expression
327 is void. A void expression is an expression where the type of the
328 result is "void". For example, some convenience variables may be
329 "void" when evaluated (e.g., "$_exitcode" before the execution of
330 the program being debugged; or an undefined convenience variable).
331 Another example, when calling a function whose return type is
334 * The "maintenance print objfiles" command now takes an optional regexp.
336 * The "catch syscall" command now works on arm*-linux* targets.
338 * GDB now consistently shows "<not saved>" when printing values of
339 registers the debug info indicates have not been saved in the frame
340 and there's nowhere to retrieve them from
341 (callee-saved/call-clobbered registers):
346 (gdb) info registers rax
349 Before, the former would print "<optimized out>", and the latter
350 "*value not available*".
352 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
357 ** Frame filters and frame decorators have been added.
358 ** Temporary breakpoints are now supported.
359 ** Line tables representation has been added.
360 ** New attribute 'parent_type' for gdb.Field objects.
361 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
362 ** New attribute 'name' for gdb.Type objects.
366 Nios II ELF nios2*-*-elf
367 Nios II GNU/Linux nios2*-*-linux
368 Texas Instruments MSP430 msp430*-*-elf
370 * Removed native configurations
372 Support for these a.out NetBSD and OpenBSD obsolete configurations has
373 been removed. ELF variants of these configurations are kept supported.
375 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
376 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
377 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
378 i[34567]86-*-openbsd3.[0-3]
379 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
380 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
381 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
385 Like "catch throw", but catches a re-thrown exception.
387 Renamed from old "maint check-symtabs".
389 Perform consistency checks on symtabs.
391 Expand symtabs matching an optional regexp.
394 Display the details of GDB configure-time options.
396 maint set|show per-command
397 maint set|show per-command space
398 maint set|show per-command time
399 maint set|show per-command symtab
400 Enable display of per-command gdb resource usage.
402 remove-symbol-file FILENAME
403 remove-symbol-file -a ADDRESS
404 Remove a symbol file added via add-symbol-file. The file to remove
405 can be identified by its filename or by an address that lies within
406 the boundaries of this symbol file in memory.
409 info exceptions REGEXP
410 Display the list of Ada exceptions defined in the program being
411 debugged. If provided, only the exceptions whose names match REGEXP
416 set debug symfile off|on
418 Control display of debugging info regarding reading symbol files and
419 symbol tables within those files
421 set print raw frame-arguments
422 show print raw frame-arguments
423 Set/show whether to print frame arguments in raw mode,
424 disregarding any defined pretty-printers.
426 set remote trace-status-packet
427 show remote trace-status-packet
428 Set/show the use of remote protocol qTStatus packet.
432 Control display of debugging messages related to Nios II targets.
436 Control whether target-assisted range stepping is enabled.
438 set startup-with-shell
439 show startup-with-shell
440 Specifies whether Unix child processes are started via a shell or
445 Use the target memory cache for accesses to the code segment. This
446 improves performance of remote debugging (particularly disassembly).
448 * You can now use a literal value 'unlimited' for options that
449 interpret 0 or -1 as meaning "unlimited". E.g., "set
450 trace-buffer-size unlimited" is now an alias for "set
451 trace-buffer-size -1" and "set height unlimited" is now an alias for
454 * The "set debug symtab-create" debugging option of GDB has been changed to
455 accept a verbosity level. 0 means "off", 1 provides basic debugging
456 output, and values of 2 or greater provides more verbose output.
458 * New command-line options
460 Display the details of GDB configure-time options.
462 * The command 'tsave' can now support new option '-ctf' to save trace
463 buffer in Common Trace Format.
465 * Newly installed $prefix/bin/gcore acts as a shell interface for the
468 * GDB now implements the the C++ 'typeid' operator.
470 * The new convenience variable $_exception holds the exception being
471 thrown or caught at an exception-related catchpoint.
473 * The exception-related catchpoints, like "catch throw", now accept a
474 regular expression which can be used to filter exceptions by type.
476 * The new convenience variable $_exitsignal is automatically set to
477 the terminating signal number when the program being debugged dies
478 due to an uncaught signal.
482 ** All MI commands now accept an optional "--language" option.
483 Support for this feature can be verified by using the "-list-features"
484 command, which should contain "language-option".
486 ** The new command -info-gdb-mi-command allows the user to determine
487 whether a GDB/MI command is supported or not.
489 ** The "^error" result record returned when trying to execute an undefined
490 GDB/MI command now provides a variable named "code" whose content is the
491 "undefined-command" error code. Support for this feature can be verified
492 by using the "-list-features" command, which should contain
493 "undefined-command-error-code".
495 ** The -trace-save MI command can optionally save trace buffer in Common
498 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
500 ** The command -data-list-register-values now accepts an optional
501 "--skip-unavailable" option. When used, only the available registers
504 ** The new command -trace-frame-collected dumps collected variables,
505 computed expressions, tvars, memory and registers in a traceframe.
507 ** The commands -stack-list-locals, -stack-list-arguments and
508 -stack-list-variables now accept an option "--skip-unavailable".
509 When used, only the available locals or arguments are displayed.
511 ** The -exec-run command now accepts an optional "--start" option.
512 When used, the command follows the same semantics as the "start"
513 command, stopping the program's execution at the start of its
514 main subprogram. Support for this feature can be verified using
515 the "-list-features" command, which should contain
516 "exec-run-start-option".
518 ** The new commands -catch-assert and -catch-exceptions insert
519 catchpoints stopping the program when Ada exceptions are raised.
521 ** The new command -info-ada-exceptions provides the equivalent of
522 the new "info exceptions" command.
524 * New system-wide configuration scripts
525 A GDB installation now provides scripts suitable for use as system-wide
526 configuration scripts for the following systems:
530 * GDB now supports target-assigned range stepping with remote targets.
531 This improves the performance of stepping source lines by reducing
532 the number of control packets from/to GDB. See "New remote packets"
535 * GDB now understands the element 'tvar' in the XML traceframe info.
536 It has the id of the collected trace state variables.
538 * On S/390 targets that provide the transactional-execution feature,
539 the program interruption transaction diagnostic block (TDB) is now
540 represented as a number of additional "registers" in GDB.
546 The vCont packet supports a new 'r' action, that tells the remote
547 stub to step through an address range itself, without GDB
548 involvemement at each single-step.
550 qXfer:libraries-svr4:read's annex
551 The previously unused annex of the qXfer:libraries-svr4:read packet
552 is now used to support passing an argument list. The remote stub
553 reports support for this argument list to GDB's qSupported query.
554 The defined arguments are "start" and "prev", used to reduce work
555 necessary for library list updating, resulting in significant
558 * New features in the GDB remote stub, GDBserver
560 ** GDBserver now supports target-assisted range stepping. Currently
561 enabled on x86/x86_64 GNU/Linux targets.
563 ** GDBserver now adds element 'tvar' in the XML in the reply to
564 'qXfer:traceframe-info:read'. It has the id of the collected
565 trace state variables.
567 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
570 * New 'z' formatter for printing and examining memory, this displays the
571 value as hexadecimal zero padded on the left to the size of the type.
573 * GDB can now use Windows x64 unwinding data.
575 * The "set remotebaud" command has been replaced by "set serial baud".
576 Similarly, "show remotebaud" has been replaced by "show serial baud".
577 The "set remotebaud" and "show remotebaud" commands are still available
578 to provide backward compatibility with older versions of GDB.
580 *** Changes in GDB 7.6
582 * Target record has been renamed to record-full.
583 Record/replay is now enabled with the "record full" command.
584 This also affects settings that are associated with full record/replay
585 that have been moved from "set/show record" to "set/show record full":
587 set|show record full insn-number-max
588 set|show record full stop-at-limit
589 set|show record full memory-query
591 * A new record target "record-btrace" has been added. The new target
592 uses hardware support to record the control-flow of a process. It
593 does not support replaying the execution, but it implements the
594 below new commands for investigating the recorded execution log.
595 This new recording method can be enabled using:
599 The "record-btrace" target is only available on Intel Atom processors
600 and requires a Linux kernel 2.6.32 or later.
602 * Two new commands have been added for record/replay to give information
603 about the recorded execution without having to replay the execution.
604 The commands are only supported by "record btrace".
606 record instruction-history prints the execution history at
607 instruction granularity
609 record function-call-history prints the execution history at
612 * New native configurations
614 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
615 FreeBSD/powerpc powerpc*-*-freebsd
616 x86_64/Cygwin x86_64-*-cygwin*
617 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
621 ARM AArch64 aarch64*-*-elf
622 ARM AArch64 GNU/Linux aarch64*-*-linux
623 Lynx 178 PowerPC powerpc-*-lynx*178
624 x86_64/Cygwin x86_64-*-cygwin*
625 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
627 * If the configured location of system.gdbinit file (as given by the
628 --with-system-gdbinit option at configure time) is in the
629 data-directory (as specified by --with-gdb-datadir at configure
630 time) or in one of its subdirectories, then GDB will look for the
631 system-wide init file in the directory specified by the
632 --data-directory command-line option.
634 * New command line options:
636 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
637 other initialization files, unlike -nx which disables all of them.
639 * Removed command line options
641 -epoch This was used by the gdb mode in Epoch, an ancient fork of
644 * The 'ptype' and 'whatis' commands now accept an argument to control
647 * 'info proc' now works on some core files.
651 ** Vectors can be created with gdb.Type.vector.
653 ** Python's atexit.register now works in GDB.
655 ** Types can be pretty-printed via a Python API.
657 ** Python 3 is now supported (in addition to Python 2.4 or later)
659 ** New class gdb.Architecture exposes GDB's internal representation
660 of architecture in the Python API.
662 ** New method Frame.architecture returns the gdb.Architecture object
663 corresponding to the frame's architecture.
665 * New Python-based convenience functions:
667 ** $_memeq(buf1, buf2, length)
668 ** $_streq(str1, str2)
670 ** $_regex(str, regex)
672 * The 'cd' command now defaults to using '~' (the home directory) if not
675 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
676 default for GCC since November 2000.
678 * The command 'forward-search' can now be abbreviated as 'fo'.
680 * The command 'info tracepoints' can now display 'installed on target'
681 or 'not installed on target' for each non-pending location of tracepoint.
683 * New configure options
685 --enable-libmcheck/--disable-libmcheck
686 By default, development versions are built with -lmcheck on hosts
687 that support it, in order to help track memory corruption issues.
688 Release versions, on the other hand, are built without -lmcheck
689 by default. The --enable-libmcheck/--disable-libmcheck configure
690 options allow the user to override that default.
691 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
692 This configure option allows the user to build GDB with
693 libbabeltrace using which GDB can read Common Trace Format data.
695 * New commands (for set/show, see "New options" below)
698 Catch signals. This is similar to "handle", but allows commands and
699 conditions to be attached.
702 List the BFDs known to GDB.
704 python-interactive [command]
706 Start a Python interactive prompt, or evaluate the optional command
707 and print the result of expressions.
710 "py" is a new alias for "python".
712 enable type-printer [name]...
713 disable type-printer [name]...
714 Enable or disable type printers.
718 ** For the Renesas Super-H architecture, the "regs" command has been removed
719 (has been deprecated in GDB 7.5), and "info all-registers" should be used
724 set print type methods (on|off)
725 show print type methods
726 Control whether method declarations are displayed by "ptype".
727 The default is to show them.
729 set print type typedefs (on|off)
730 show print type typedefs
731 Control whether typedef definitions are displayed by "ptype".
732 The default is to show them.
734 set filename-display basename|relative|absolute
735 show filename-display
736 Control the way in which filenames is displayed.
737 The default is "relative", which preserves previous behavior.
739 set trace-buffer-size
740 show trace-buffer-size
741 Request target to change the size of trace buffer.
743 set remote trace-buffer-size-packet auto|on|off
744 show remote trace-buffer-size-packet
745 Control the use of the remote protocol `QTBuffer:size' packet.
749 Control display of debugging messages related to ARM AArch64.
752 set debug coff-pe-read
753 show debug coff-pe-read
754 Control display of debugging messages related to reading of COFF/PE
759 Control display of debugging messages related to Mach-O symbols
762 set debug notification
763 show debug notification
764 Control display of debugging info for async remote notification.
768 ** Command parameter changes are now notified using new async record
769 "=cmd-param-changed".
770 ** Trace frame changes caused by command "tfind" are now notified using
771 new async record "=traceframe-changed".
772 ** The creation, deletion and modification of trace state variables
773 are now notified using new async records "=tsv-created",
774 "=tsv-deleted" and "=tsv-modified".
775 ** The start and stop of process record are now notified using new
776 async record "=record-started" and "=record-stopped".
777 ** Memory changes are now notified using new async record
779 ** The data-disassemble command response will include a "fullname" field
780 containing the absolute file name when source has been requested.
781 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
782 command, to allow pattern filling of memory areas.
783 ** New commands "-catch-load"/"-catch-unload" added for intercepting
784 library load/unload events.
785 ** The response to breakpoint commands and breakpoint async records
786 includes an "installed" field containing a boolean state about each
787 non-pending tracepoint location is whether installed on target or not.
788 ** Output of the "-trace-status" command includes a "trace-file" field
789 containing the name of the trace file being examined. This field is
790 optional, and only present when examining a trace file.
791 ** The "fullname" field is now always present along with the "file" field,
792 even if the file cannot be found by GDB.
794 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
795 You must have the LZMA library available when configuring GDB for this
796 feature to be enabled. For more information, see:
797 http://fedoraproject.org/wiki/Features/MiniDebugInfo
802 Set the size of trace buffer. The remote stub reports support for this
803 packet to gdb's qSupported query.
806 Enable Branch Trace Store (BTS)-based branch tracing for the current
807 thread. The remote stub reports support for this packet to gdb's
811 Disable branch tracing for the current thread. The remote stub reports
812 support for this packet to gdb's qSupported query.
815 Read the traced branches for the current thread. The remote stub
816 reports support for this packet to gdb's qSupported query.
818 *** Changes in GDB 7.5
820 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
821 for more x32 ABI info.
823 * GDB now supports access to MIPS DSP registers on Linux targets.
825 * GDB now supports debugging microMIPS binaries.
827 * The "info os" command on GNU/Linux can now display information on
828 several new classes of objects managed by the operating system:
829 "info os procgroups" lists process groups
830 "info os files" lists file descriptors
831 "info os sockets" lists internet-domain sockets
832 "info os shm" lists shared-memory regions
833 "info os semaphores" lists semaphores
834 "info os msg" lists message queues
835 "info os modules" lists loaded kernel modules
837 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
838 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
839 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
840 options and inspect the probe arguments using the new $_probe_arg family
841 of convenience variables. You can obtain more information about SystemTap
842 in <http://sourceware.org/systemtap/>.
844 * GDB now supports reversible debugging on ARM, it allows you to
845 debug basic ARM and THUMB instructions, and provides
846 record/replay support.
848 * The option "symbol-reloading" has been deleted as it is no longer used.
852 ** GDB commands implemented in Python can now be put in command class
855 ** The "maint set python print-stack on|off" is now deleted.
857 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
858 apply "flag enum"-style pretty-printing to any enum.
860 ** gdb.lookup_symbol can now work when there is no current frame.
862 ** gdb.Symbol now has a 'line' attribute, holding the line number in
863 the source at which the symbol was defined.
865 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
866 method 'value'. The former indicates whether the symbol needs a
867 frame in order to compute its value, and the latter computes the
870 ** A new method 'referenced_value' on gdb.Value objects which can
871 dereference pointer as well as C++ reference values.
873 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
874 which return the global and static blocks (as gdb.Block objects),
875 of the underlying symbol table, respectively.
877 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
878 object associated with a PC value.
880 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
881 of the address range occupied by code for the current source line.
883 * Go language support.
884 GDB now supports debugging programs written in the Go programming
887 * GDBserver now supports stdio connections.
888 E.g. (gdb) target remote | ssh myhost gdbserver - hello
890 * The binary "gdbtui" can no longer be built or installed.
891 Use "gdb -tui" instead.
893 * GDB will now print "flag" enums specially. A flag enum is one where
894 all the enumerator values have no bits in common when pairwise
895 "and"ed. When printing a value whose type is a flag enum, GDB will
896 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
897 (gdb) print (enum E) 3
900 * The filename part of a linespec will now match trailing components
901 of a source file name. For example, "break gcc/expr.c:1000" will
902 now set a breakpoint in build/gcc/expr.c, but not
905 * The "info proc" and "generate-core-file" commands will now also
906 work on remote targets connected to GDBserver on Linux.
908 * The command "info catch" has been removed. It has been disabled
911 * The "catch exception" and "catch assert" commands now accept
912 a condition at the end of the command, much like the "break"
913 command does. For instance:
915 (gdb) catch exception Constraint_Error if Barrier = True
917 Previously, it was possible to add a condition to such catchpoints,
918 but it had to be done as a second step, after the catchpoint had been
919 created, using the "condition" command.
921 * The "info static-tracepoint-marker" command will now also work on
922 native Linux targets with in-process agent.
924 * GDB can now set breakpoints on inlined functions.
926 * The .gdb_index section has been updated to include symbols for
927 inlined functions. GDB will ignore older .gdb_index sections by
928 default, which could cause symbol files to be loaded more slowly
929 until their .gdb_index sections can be recreated. The new command
930 "set use-deprecated-index-sections on" will cause GDB to use any older
931 .gdb_index sections it finds. This will restore performance, but the
932 ability to set breakpoints on inlined functions will be lost in symbol
933 files with older .gdb_index sections.
935 The .gdb_index section has also been updated to record more information
936 about each symbol. This speeds up the "info variables", "info functions"
937 and "info types" commands when used with programs having the .gdb_index
938 section, as well as speeding up debugging with shared libraries using
939 the .gdb_index section.
941 * Ada support for GDB/MI Variable Objects has been added.
943 * GDB can now support 'breakpoint always-inserted mode' in 'record'
948 ** New command -info-os is the MI equivalent of "info os".
950 ** Output logs ("set logging" and related) now include MI output.
954 ** "set use-deprecated-index-sections on|off"
955 "show use-deprecated-index-sections on|off"
956 Controls the use of deprecated .gdb_index sections.
958 ** "catch load" and "catch unload" can be used to stop when a shared
959 library is loaded or unloaded, respectively.
961 ** "enable count" can be used to auto-disable a breakpoint after
964 ** "info vtbl" can be used to show the virtual method tables for
965 C++ and Java objects.
967 ** "explore" and its sub commands "explore value" and "explore type"
968 can be used to recursively explore values and types of
969 expressions. These commands are available only if GDB is
970 configured with '--with-python'.
972 ** "info auto-load" shows status of all kinds of auto-loaded files,
973 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
974 sequences of commands files, "info auto-load python-scripts"
975 shows status of auto-loading Python script files,
976 "info auto-load local-gdbinit" shows status of loading init file
977 (.gdbinit) from current directory and "info auto-load libthread-db" shows
978 status of inferior specific thread debugging shared library loading.
980 ** "info auto-load-scripts", "set auto-load-scripts on|off"
981 and "show auto-load-scripts" commands have been deprecated, use their
982 "info auto-load python-scripts", "set auto-load python-scripts on|off"
983 and "show auto-load python-scripts" counterparts instead.
985 ** "dprintf location,format,args..." creates a dynamic printf, which
986 is basically a breakpoint that does a printf and immediately
987 resumes your program's execution, so it is like a printf that you
988 can insert dynamically at runtime instead of at compiletime.
990 ** "set print symbol"
992 Controls whether GDB attempts to display the symbol, if any,
993 corresponding to addresses it prints. This defaults to "on", but
994 you can set it to "off" to restore GDB's previous behavior.
996 * Deprecated commands
998 ** For the Renesas Super-H architecture, the "regs" command has been
999 deprecated, and "info all-registers" should be used instead.
1003 Renesas RL78 rl78-*-elf
1004 HP OpenVMS ia64 ia64-hp-openvms*
1006 * GDBserver supports evaluation of breakpoint conditions. When
1007 support is advertised by GDBserver, GDB may be told to send the
1008 breakpoint conditions in bytecode form to GDBserver. GDBserver
1009 will only report the breakpoint trigger to GDB when its condition
1014 set mips compression
1015 show mips compression
1016 Select the compressed ISA encoding used in functions that have no symbol
1017 information available. The encoding can be set to either of:
1020 and is updated automatically from ELF file flags if available.
1022 set breakpoint condition-evaluation
1023 show breakpoint condition-evaluation
1024 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1025 GDBserver ("target"). Default option "auto" chooses the most efficient
1027 This option can improve debugger efficiency depending on the speed of the
1031 Disable auto-loading globally.
1034 Show auto-loading setting of all kinds of auto-loaded files.
1036 set auto-load gdb-scripts on|off
1037 show auto-load gdb-scripts
1038 Control auto-loading of GDB canned sequences of commands files.
1040 set auto-load python-scripts on|off
1041 show auto-load python-scripts
1042 Control auto-loading of Python script files.
1044 set auto-load local-gdbinit on|off
1045 show auto-load local-gdbinit
1046 Control loading of init file (.gdbinit) from current directory.
1048 set auto-load libthread-db on|off
1049 show auto-load libthread-db
1050 Control auto-loading of inferior specific thread debugging shared library.
1052 set auto-load scripts-directory <dir1>[:<dir2>...]
1053 show auto-load scripts-directory
1054 Set a list of directories from which to load auto-loaded scripts.
1055 Automatically loaded Python scripts and GDB scripts are located in one
1056 of the directories listed by this option.
1057 The delimiter (':' above) may differ according to the host platform.
1059 set auto-load safe-path <dir1>[:<dir2>...]
1060 show auto-load safe-path
1061 Set a list of directories from which it is safe to auto-load files.
1062 The delimiter (':' above) may differ according to the host platform.
1064 set debug auto-load on|off
1065 show debug auto-load
1066 Control display of debugging info for auto-loading the files above.
1068 set dprintf-style gdb|call|agent
1070 Control the way in which a dynamic printf is performed; "gdb"
1071 requests a GDB printf command, while "call" causes dprintf to call a
1072 function in the inferior. "agent" requests that the target agent
1073 (such as GDBserver) do the printing.
1075 set dprintf-function <expr>
1076 show dprintf-function
1077 set dprintf-channel <expr>
1078 show dprintf-channel
1079 Set the function and optional first argument to the call when using
1080 the "call" style of dynamic printf.
1082 set disconnected-dprintf on|off
1083 show disconnected-dprintf
1084 Control whether agent-style dynamic printfs continue to be in effect
1085 after GDB disconnects.
1087 * New configure options
1089 --with-auto-load-dir
1090 Configure default value for the 'set auto-load scripts-directory'
1091 setting above. It defaults to '$debugdir:$datadir/auto-load',
1092 $debugdir representing global debugging info directories (available
1093 via 'show debug-file-directory') and $datadir representing GDB's data
1094 directory (available via 'show data-directory').
1096 --with-auto-load-safe-path
1097 Configure default value for the 'set auto-load safe-path' setting
1098 above. It defaults to the --with-auto-load-dir setting.
1100 --without-auto-load-safe-path
1101 Set 'set auto-load safe-path' to '/', effectively disabling this
1104 * New remote packets
1106 z0/z1 conditional breakpoints extension
1108 The z0/z1 breakpoint insertion packets have been extended to carry
1109 a list of conditional expressions over to the remote stub depending on the
1110 condition evaluation mode. The use of this extension can be controlled
1111 via the "set remote conditional-breakpoints-packet" command.
1115 Specify the signals which the remote stub may pass to the debugged
1116 program without GDB involvement.
1118 * New command line options
1120 --init-command=FILE, -ix Like --command, -x but execute it
1121 before loading inferior.
1122 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1123 execute it before loading inferior.
1125 *** Changes in GDB 7.4
1127 * GDB now handles ambiguous linespecs more consistently; the existing
1128 FILE:LINE support has been expanded to other types of linespecs. A
1129 breakpoint will now be set on all matching locations in all
1130 inferiors, and locations will be added or removed according to
1133 * GDB now allows you to skip uninteresting functions and files when
1134 stepping with the "skip function" and "skip file" commands.
1136 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1137 and "show remote hardware-watchpoint-length-limit". These allows to
1138 set or show the maximum length limit (in bytes) of a remote
1139 target hardware watchpoint.
1141 This allows e.g. to use "unlimited" hardware watchpoints with the
1142 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1143 watchpoints are slower than real hardware watchpoints but are
1144 significantly faster than gdb software watchpoints.
1148 ** The register_pretty_printer function in module gdb.printing now takes
1149 an optional `replace' argument. If True, the new printer replaces any
1152 ** The "maint set python print-stack on|off" command has been
1153 deprecated and will be deleted in GDB 7.5.
1154 A new command: "set python print-stack none|full|message" has
1155 replaced it. Additionally, the default for "print-stack" is
1156 now "message", which just prints the error message without
1159 ** A prompt substitution hook (prompt_hook) is now available to the
1162 ** A new Python module, gdb.prompt has been added to the GDB Python
1163 modules library. This module provides functionality for
1164 escape sequences in prompts (used by set/show
1165 extended-prompt). These escape sequences are replaced by their
1166 corresponding value.
1168 ** Python commands and convenience-functions located in
1169 'data-directory'/python/gdb/command and
1170 'data-directory'/python/gdb/function are now automatically loaded
1173 ** Blocks now provide four new attributes. global_block and
1174 static_block will return the global and static blocks
1175 respectively. is_static and is_global are boolean attributes
1176 that indicate if the block is one of those two types.
1178 ** Symbols now provide the "type" attribute, the type of the symbol.
1180 ** The "gdb.breakpoint" function has been deprecated in favor of
1183 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1184 of a function. This class is based on the "finish" command
1185 available in the CLI.
1187 ** Type objects for struct and union types now allow access to
1188 the fields using standard Python dictionary (mapping) methods.
1189 For example, "some_type['myfield']" now works, as does
1190 "some_type.items()".
1192 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1195 ** A new function, "deep_items" has been added to the gdb.types
1196 module in the GDB Python modules library. This function returns
1197 an iterator over the fields of a struct or union type. Unlike
1198 the standard Python "iteritems" method, it will recursively traverse
1199 any anonymous fields.
1203 ** "*stopped" events can report several new "reason"s, such as
1206 ** Breakpoint changes are now notified using new async records, like
1207 "=breakpoint-modified".
1209 ** New command -ada-task-info.
1211 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1212 $sdir specifies the default system locations of shared libraries.
1213 $pdir specifies the directory where the libpthread used by the application
1216 GDB no longer looks in $sdir and $pdir after it has searched the directories
1217 mentioned in libthread-db-search-path. If you want to search those
1218 directories, they must be specified in libthread-db-search-path.
1219 The default value of libthread-db-search-path on GNU/Linux and Solaris
1220 systems is now "$sdir:$pdir".
1222 $pdir is not supported by gdbserver, it is currently ignored.
1223 $sdir is supported by gdbserver.
1225 * New configure option --with-iconv-bin.
1226 When using the internationalization support like the one in the GNU C
1227 library, GDB will invoke the "iconv" program to get a list of supported
1228 character sets. If this program lives in a non-standard location, one can
1229 use this option to specify where to find it.
1231 * When natively debugging programs on PowerPC BookE processors running
1232 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1233 watchpoints, which specify a mask in addition to an address to watch.
1234 The mask specifies that some bits of an address (the bits which are
1235 reset in the mask) should be ignored when matching the address accessed
1236 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1237 section in the user manual for more details.
1239 * The new option --once causes GDBserver to stop listening for connections once
1240 the first connection is made. The listening port used by GDBserver will
1241 become available after that.
1243 * New commands "info macros" and "alias" have been added.
1245 * New function parameters suffix @entry specifies value of function parameter
1246 at the time the function got called. Entry values are available only since
1252 "!" is now an alias of the "shell" command.
1253 Note that no space is needed between "!" and SHELL COMMAND.
1257 watch EXPRESSION mask MASK_VALUE
1258 The watch command now supports the mask argument which allows creation
1259 of masked watchpoints, if the current architecture supports this feature.
1261 info auto-load-scripts [REGEXP]
1262 This command was formerly named "maintenance print section-scripts".
1263 It is now generally useful and is no longer a maintenance-only command.
1265 info macro [-all] [--] MACRO
1266 The info macro command has new options `-all' and `--'. The first for
1267 printing all definitions of a macro. The second for explicitly specifying
1268 the end of arguments and the beginning of the macro name in case the macro
1269 name starts with a hyphen.
1271 collect[/s] EXPRESSIONS
1272 The tracepoint collect command now takes an optional modifier "/s"
1273 that directs it to dereference pointer-to-character types and
1274 collect the bytes of memory up to a zero byte. The behavior is
1275 similar to what you see when you use the regular print command on a
1276 string. An optional integer following the "/s" sets a bound on the
1277 number of bytes that will be collected.
1280 The trace start command now interprets any supplied arguments as a
1281 note to be recorded with the trace run, with an effect similar to
1282 setting the variable trace-notes.
1285 The trace stop command now interprets any arguments as a note to be
1286 mentioned along with the tstatus report that the trace was stopped
1287 with a command. The effect is similar to setting the variable
1290 * Tracepoints can now be enabled and disabled at any time after a trace
1291 experiment has been started using the standard "enable" and "disable"
1292 commands. It is now possible to start a trace experiment with no enabled
1293 tracepoints; GDB will display a warning, but will allow the experiment to
1294 begin, assuming that tracepoints will be enabled as needed while the trace
1297 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1298 locations with 4-byte instructions, when they were previously
1299 limited to locations with instructions of 5 bytes or longer.
1303 set debug dwarf2-read
1304 show debug dwarf2-read
1305 Turns on or off display of debugging messages related to reading
1306 DWARF debug info. The default is off.
1308 set debug symtab-create
1309 show debug symtab-create
1310 Turns on or off display of debugging messages related to symbol table
1311 creation. The default is off.
1314 show extended-prompt
1315 Set the GDB prompt, and allow escape sequences to be inserted to
1316 display miscellaneous information (see 'help set extended-prompt'
1317 for the list of sequences). This prompt (and any information
1318 accessed through the escape sequences) is updated every time the
1319 prompt is displayed.
1321 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1322 show print entry-values
1323 Set printing of frame argument values at function entry. In some cases
1324 GDB can determine the value of function argument which was passed by the
1325 function caller, even if the value was modified inside the called function.
1327 set debug entry-values
1328 show debug entry-values
1329 Control display of debugging info for determining frame argument values at
1330 function entry and virtual tail call frames.
1332 set basenames-may-differ
1333 show basenames-may-differ
1334 Set whether a source file may have multiple base names.
1335 (A "base name" is the name of a file with the directory part removed.
1336 Example: The base name of "/home/user/hello.c" is "hello.c".)
1337 If set, GDB will canonicalize file names (e.g., expand symlinks)
1338 before comparing them. Canonicalization is an expensive operation,
1339 but it allows the same file be known by more than one base name.
1340 If not set (the default), all source files are assumed to have just
1341 one base name, and gdb will do file name comparisons more efficiently.
1347 Set a user name and notes for the current and any future trace runs.
1348 This is useful for long-running and/or disconnected traces, to
1349 inform others (or yourself) as to who is running the trace, supply
1350 contact information, or otherwise explain what is going on.
1352 set trace-stop-notes
1353 show trace-stop-notes
1354 Set a note attached to the trace run, that is displayed when the
1355 trace has been stopped by a tstop command. This is useful for
1356 instance as an explanation, if you are stopping a trace run that was
1357 started by someone else.
1359 * New remote packets
1363 Dynamically enable a tracepoint in a started trace experiment.
1367 Dynamically disable a tracepoint in a started trace experiment.
1371 Set the user and notes of the trace run.
1375 Query the current status of a tracepoint.
1379 Query the minimum length of instruction at which a fast tracepoint may
1382 * Dcache size (number of lines) and line-size are now runtime-configurable
1383 via "set dcache line" and "set dcache line-size" commands.
1387 Texas Instruments TMS320C6x tic6x-*-*
1391 Renesas RL78 rl78-*-elf
1393 *** Changes in GDB 7.3.1
1395 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1397 *** Changes in GDB 7.3
1399 * GDB has a new command: "thread find [REGEXP]".
1400 It finds the thread id whose name, target id, or thread extra info
1401 matches the given regular expression.
1403 * The "catch syscall" command now works on mips*-linux* targets.
1405 * The -data-disassemble MI command now supports modes 2 and 3 for
1406 dumping the instruction opcodes.
1408 * New command line options
1410 -data-directory DIR Specify DIR as the "data-directory".
1411 This is mostly for testing purposes.
1413 * The "maint set python auto-load on|off" command has been renamed to
1414 "set auto-load-scripts on|off".
1416 * GDB has a new command: "set directories".
1417 It is like the "dir" command except that it replaces the
1418 source path list instead of augmenting it.
1420 * GDB now understands thread names.
1422 On GNU/Linux, "info threads" will display the thread name as set by
1423 prctl or pthread_setname_np.
1425 There is also a new command, "thread name", which can be used to
1426 assign a name internally for GDB to display.
1429 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1430 has been integrated into GDB.
1434 ** The function gdb.Write now accepts an optional keyword 'stream'.
1435 This keyword, when provided, will direct the output to either
1436 stdout, stderr, or GDB's logging output.
1438 ** Parameters can now be be sub-classed in Python, and in particular
1439 you may implement the get_set_doc and get_show_doc functions.
1440 This improves how Parameter set/show documentation is processed
1441 and allows for more dynamic content.
1443 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1444 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1445 have an is_valid method.
1447 ** Breakpoints can now be sub-classed in Python, and in particular
1448 you may implement a 'stop' function that is executed each time
1449 the inferior reaches that breakpoint.
1451 ** New function gdb.lookup_global_symbol looks up a global symbol.
1453 ** GDB values in Python are now callable if the value represents a
1454 function. For example, if 'some_value' represents a function that
1455 takes two integer parameters and returns a value, you can call
1456 that function like so:
1458 result = some_value (10,20)
1460 ** Module gdb.types has been added.
1461 It contains a collection of utilities for working with gdb.Types objects:
1462 get_basic_type, has_field, make_enum_dict.
1464 ** Module gdb.printing has been added.
1465 It contains utilities for writing and registering pretty-printers.
1466 New classes: PrettyPrinter, SubPrettyPrinter,
1467 RegexpCollectionPrettyPrinter.
1468 New function: register_pretty_printer.
1470 ** New commands "info pretty-printers", "enable pretty-printer" and
1471 "disable pretty-printer" have been added.
1473 ** gdb.parameter("directories") is now available.
1475 ** New function gdb.newest_frame returns the newest frame in the
1478 ** The gdb.InferiorThread class has a new "name" attribute. This
1479 holds the thread's name.
1481 ** Python Support for Inferior events.
1482 Python scripts can add observers to be notified of events
1483 occurring in the process being debugged.
1484 The following events are currently supported:
1485 - gdb.events.cont Continue event.
1486 - gdb.events.exited Inferior exited event.
1487 - gdb.events.stop Signal received, and Breakpoint hit events.
1491 ** GDB now puts template parameters in scope when debugging in an
1492 instantiation. For example, if you have:
1494 template<int X> int func (void) { return X; }
1496 then if you step into func<5>, "print X" will show "5". This
1497 feature requires proper debuginfo support from the compiler; it
1498 was added to GCC 4.5.
1500 ** The motion commands "next", "finish", "until", and "advance" now
1501 work better when exceptions are thrown. In particular, GDB will
1502 no longer lose control of the inferior; instead, the GDB will
1503 stop the inferior at the point at which the exception is caught.
1504 This functionality requires a change in the exception handling
1505 code that was introduced in GCC 4.5.
1507 * GDB now follows GCC's rules on accessing volatile objects when
1508 reading or writing target state during expression evaluation.
1509 One notable difference to prior behavior is that "print x = 0"
1510 no longer generates a read of x; the value of the assignment is
1511 now always taken directly from the value being assigned.
1513 * GDB now has some support for using labels in the program's source in
1514 linespecs. For instance, you can use "advance label" to continue
1515 execution to a label.
1517 * GDB now has support for reading and writing a new .gdb_index
1518 section. This section holds a fast index of DWARF debugging
1519 information and can be used to greatly speed up GDB startup and
1520 operation. See the documentation for `save gdb-index' for details.
1522 * The "watch" command now accepts an optional "-location" argument.
1523 When used, this causes GDB to watch the memory referred to by the
1524 expression. Such a watchpoint is never deleted due to it going out
1527 * GDB now supports thread debugging of core dumps on GNU/Linux.
1529 GDB now activates thread debugging using the libthread_db library
1530 when debugging GNU/Linux core dumps, similarly to when debugging
1531 live processes. As a result, when debugging a core dump file, GDB
1532 is now able to display pthread_t ids of threads. For example, "info
1533 threads" shows the same output as when debugging the process when it
1534 was live. In earlier releases, you'd see something like this:
1537 * 1 LWP 6780 main () at main.c:10
1539 While now you see this:
1542 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1544 It is also now possible to inspect TLS variables when debugging core
1547 When debugging a core dump generated on a machine other than the one
1548 used to run GDB, you may need to point GDB at the correct
1549 libthread_db library with the "set libthread-db-search-path"
1550 command. See the user manual for more details on this command.
1552 * When natively debugging programs on PowerPC BookE processors running
1553 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1554 which stop execution of the inferior whenever it executes an instruction
1555 at any address within the specified range. See the "PowerPC Embedded"
1556 section in the user manual for more details.
1558 * New features in the GDB remote stub, GDBserver
1560 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1561 and i686 LynxOS (version 5.x).
1563 ** GDBserver is now supported on Blackfin Linux.
1565 * New native configurations
1567 ia64 HP-UX ia64-*-hpux*
1571 Analog Devices, Inc. Blackfin Processor bfin-*
1573 * Ada task switching is now supported on sparc-elf targets when
1574 debugging a program using the Ravenscar Profile. For more information,
1575 see the "Tasking Support when using the Ravenscar Profile" section
1576 in the GDB user manual.
1578 * Guile support was removed.
1580 * New features in the GNU simulator
1582 ** The --map-info flag lists all known core mappings.
1584 ** CFI flashes may be simulated via the "cfi" device.
1586 *** Changes in GDB 7.2
1588 * Shared library support for remote targets by default
1590 When GDB is configured for a generic, non-OS specific target, like
1591 for example, --target=arm-eabi or one of the many *-*-elf targets,
1592 GDB now queries remote stubs for loaded shared libraries using the
1593 `qXfer:libraries:read' packet. Previously, shared library support
1594 was always disabled for such configurations.
1598 ** Argument Dependent Lookup (ADL)
1600 In C++ ADL lookup directs function search to the namespaces of its
1601 arguments even if the namespace has not been imported.
1611 Here the compiler will search for `foo' in the namespace of 'b'
1612 and find A::foo. GDB now supports this. This construct is commonly
1613 used in the Standard Template Library for operators.
1615 ** Improved User Defined Operator Support
1617 In addition to member operators, GDB now supports lookup of operators
1618 defined in a namespace and imported with a `using' directive, operators
1619 defined in the global scope, operators imported implicitly from an
1620 anonymous namespace, and the ADL operators mentioned in the previous
1622 GDB now also supports proper overload resolution for all the previously
1623 mentioned flavors of operators.
1625 ** static const class members
1627 Printing of static const class members that are initialized in the
1628 class definition has been fixed.
1630 * Windows Thread Information Block access.
1632 On Windows targets, GDB now supports displaying the Windows Thread
1633 Information Block (TIB) structure. This structure is visible either
1634 by using the new command `info w32 thread-information-block' or, by
1635 dereferencing the new convenience variable named `$_tlb', a
1636 thread-specific pointer to the TIB. This feature is also supported
1637 when remote debugging using GDBserver.
1639 * Static tracepoints
1641 Static tracepoints are calls in the user program into a tracing
1642 library. One such library is a port of the LTTng kernel tracer to
1643 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1644 When debugging with GDBserver, GDB now supports combining the GDB
1645 tracepoint machinery with such libraries. For example: the user can
1646 use GDB to probe a static tracepoint marker (a call from the user
1647 program into the tracing library) with the new "strace" command (see
1648 "New commands" below). This creates a "static tracepoint" in the
1649 breakpoint list, that can be manipulated with the same feature set
1650 as fast and regular tracepoints. E.g., collect registers, local and
1651 global variables, collect trace state variables, and define
1652 tracepoint conditions. In addition, the user can collect extra
1653 static tracepoint marker specific data, by collecting the new
1654 $_sdata internal variable. When analyzing the trace buffer, you can
1655 inspect $_sdata like any other variable available to GDB. For more
1656 information, see the "Tracepoints" chapter in GDB user manual. New
1657 remote packets have been defined to support static tracepoints, see
1658 the "New remote packets" section below.
1660 * Better reconstruction of tracepoints after disconnected tracing
1662 GDB will attempt to download the original source form of tracepoint
1663 definitions when starting a trace run, and then will upload these
1664 upon reconnection to the target, resulting in a more accurate
1665 reconstruction of the tracepoints that are in use on the target.
1669 You can now exercise direct control over the ways that GDB can
1670 affect your program. For instance, you can disallow the setting of
1671 breakpoints, so that the program can run continuously (assuming
1672 non-stop mode). In addition, the "observer" variable is available
1673 to switch all of the different controls; in observer mode, GDB
1674 cannot affect the target's behavior at all, which is useful for
1675 tasks like diagnosing live systems in the field.
1677 * The new convenience variable $_thread holds the number of the
1680 * New remote packets
1684 Return the address of the Windows Thread Information Block of a given thread.
1688 In response to several of the tracepoint packets, the target may now
1689 also respond with a number of intermediate `qRelocInsn' request
1690 packets before the final result packet, to have GDB handle
1691 relocating an instruction to execute at a different address. This
1692 is particularly useful for stubs that support fast tracepoints. GDB
1693 reports support for this feature in the qSupported packet.
1697 List static tracepoint markers in the target program.
1701 List static tracepoint markers at a given address in the target
1704 qXfer:statictrace:read
1706 Read the static trace data collected (by a `collect $_sdata'
1707 tracepoint action). The remote stub reports support for this packet
1708 to gdb's qSupported query.
1712 Send the current settings of GDB's permission flags.
1716 Send part of the source (textual) form of a tracepoint definition,
1717 which includes location, conditional, and action list.
1719 * The source command now accepts a -s option to force searching for the
1720 script in the source search path even if the script name specifies
1723 * New features in the GDB remote stub, GDBserver
1725 - GDBserver now support tracepoints (including fast tracepoints, and
1726 static tracepoints). The feature is currently supported by the
1727 i386-linux and amd64-linux builds. See the "Tracepoints support
1728 in gdbserver" section in the manual for more information.
1730 GDBserver JIT compiles the tracepoint's conditional agent
1731 expression bytecode into native code whenever possible for low
1732 overhead dynamic tracepoints conditionals. For such tracepoints,
1733 an expression that examines program state is evaluated when the
1734 tracepoint is reached, in order to determine whether to capture
1735 trace data. If the condition is simple and false, processing the
1736 tracepoint finishes very quickly and no data is gathered.
1738 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1739 for static tracepoints support.
1741 - GDBserver now supports x86_64 Windows 64-bit debugging.
1743 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1744 it understands register description.
1746 * The --batch flag now disables pagination and queries.
1748 * X86 general purpose registers
1750 GDB now supports reading/writing byte, word and double-word x86
1751 general purpose registers directly. This means you can use, say,
1752 $ah or $ax to refer, respectively, to the byte register AH and
1753 16-bit word register AX that are actually portions of the 32-bit
1754 register EAX or 64-bit register RAX.
1756 * The `commands' command now accepts a range of breakpoints to modify.
1757 A plain `commands' following a command that creates multiple
1758 breakpoints affects all the breakpoints set by that command. This
1759 applies to breakpoints set by `rbreak', and also applies when a
1760 single `break' command creates multiple breakpoints (e.g.,
1761 breakpoints on overloaded c++ functions).
1763 * The `rbreak' command now accepts a filename specification as part of
1764 its argument, limiting the functions selected by the regex to those
1765 in the specified file.
1767 * Support for remote debugging Windows and SymbianOS shared libraries
1768 from Unix hosts has been improved. Non Windows GDB builds now can
1769 understand target reported file names that follow MS-DOS based file
1770 system semantics, such as file names that include drive letters and
1771 use the backslash character as directory separator. This makes it
1772 possible to transparently use the "set sysroot" and "set
1773 solib-search-path" on Unix hosts to point as host copies of the
1774 target's shared libraries. See the new command "set
1775 target-file-system-kind" described below, and the "Commands to
1776 specify files" section in the user manual for more information.
1780 eval template, expressions...
1781 Convert the values of one or more expressions under the control
1782 of the string template to a command line, and call it.
1784 set target-file-system-kind unix|dos-based|auto
1785 show target-file-system-kind
1786 Set or show the assumed file system kind for target reported file
1789 save breakpoints <filename>
1790 Save all current breakpoint definitions to a file suitable for use
1791 in a later debugging session. To read the saved breakpoint
1792 definitions, use the `source' command.
1794 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1797 info static-tracepoint-markers
1798 Display information about static tracepoint markers in the target.
1800 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1801 Define a static tracepoint by probing a marker at the given
1802 function, line, address, or marker ID.
1806 Enable and disable observer mode.
1808 set may-write-registers on|off
1809 set may-write-memory on|off
1810 set may-insert-breakpoints on|off
1811 set may-insert-tracepoints on|off
1812 set may-insert-fast-tracepoints on|off
1813 set may-interrupt on|off
1814 Set individual permissions for GDB effects on the target. Note that
1815 some of these settings can have undesirable or surprising
1816 consequences, particularly when changed in the middle of a session.
1817 For instance, disabling the writing of memory can prevent
1818 breakpoints from being inserted, cause single-stepping to fail, or
1819 even crash your program, if you disable after breakpoints have been
1820 inserted. However, GDB should not crash.
1822 set record memory-query on|off
1823 show record memory-query
1824 Control whether to stop the inferior if memory changes caused
1825 by an instruction cannot be recorded.
1830 The disassemble command now supports "start,+length" form of two arguments.
1834 ** GDB now provides a new directory location, called the python directory,
1835 where Python scripts written for GDB can be installed. The location
1836 of that directory is <data-directory>/python, where <data-directory>
1837 is the GDB data directory. For more details, see section `Scripting
1838 GDB using Python' in the manual.
1840 ** The GDB Python API now has access to breakpoints, symbols, symbol
1841 tables, program spaces, inferiors, threads and frame's code blocks.
1842 Additionally, GDB Parameters can now be created from the API, and
1843 manipulated via set/show in the CLI.
1845 ** New functions gdb.target_charset, gdb.target_wide_charset,
1846 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1848 ** New exception gdb.GdbError.
1850 ** Pretty-printers are now also looked up in the current program space.
1852 ** Pretty-printers can now be individually enabled and disabled.
1854 ** GDB now looks for names of Python scripts to auto-load in a
1855 special section named `.debug_gdb_scripts', in addition to looking
1856 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1858 * Tracepoint actions were unified with breakpoint commands. In particular,
1859 there are no longer differences in "info break" output for breakpoints and
1860 tracepoints and the "commands" command can be used for both tracepoints and
1861 regular breakpoints.
1865 ARM Symbian arm*-*-symbianelf*
1867 * D language support.
1868 GDB now supports debugging programs written in the D programming
1871 * GDB now supports the extended ptrace interface for PowerPC which is
1872 available since Linux kernel version 2.6.34. This automatically enables
1873 any hardware breakpoints and additional hardware watchpoints available in
1874 the processor. The old ptrace interface exposes just one hardware
1875 watchpoint and no hardware breakpoints.
1877 * GDB is now able to use the Data Value Compare (DVC) register available on
1878 embedded PowerPC processors to implement in hardware simple watchpoint
1879 conditions of the form:
1881 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1883 This works in native GDB running on Linux kernels with the extended ptrace
1884 interface mentioned above.
1886 *** Changes in GDB 7.1
1890 ** Namespace Support
1892 GDB now supports importing of namespaces in C++. This enables the
1893 user to inspect variables from imported namespaces. Support for
1894 namepace aliasing has also been added. So, if a namespace is
1895 aliased in the current scope (e.g. namepace C=A; ) the user can
1896 print variables using the alias (e.g. (gdb) print C::x).
1900 All known bugs relating to the printing of virtual base class were
1901 fixed. It is now possible to call overloaded static methods using a
1906 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1907 and reinterpret_cast<> are now handled by the C++ expression parser.
1911 Xilinx MicroBlaze microblaze-*-*
1916 Xilinx MicroBlaze microblaze
1919 * Multi-program debugging.
1921 GDB now has support for multi-program (a.k.a. multi-executable or
1922 multi-exec) debugging. This allows for debugging multiple inferiors
1923 simultaneously each running a different program under the same GDB
1924 session. See "Debugging Multiple Inferiors and Programs" in the
1925 manual for more information. This implied some user visible changes
1926 in the multi-inferior support. For example, "info inferiors" now
1927 lists inferiors that are not running yet or that have exited
1928 already. See also "New commands" and "New options" below.
1930 * New tracing features
1932 GDB's tracepoint facility now includes several new features:
1934 ** Trace state variables
1936 GDB tracepoints now include support for trace state variables, which
1937 are variables managed by the target agent during a tracing
1938 experiment. They are useful for tracepoints that trigger each
1939 other, so for instance one tracepoint can count hits in a variable,
1940 and then a second tracepoint has a condition that is true when the
1941 count reaches a particular value. Trace state variables share the
1942 $-syntax of GDB convenience variables, and can appear in both
1943 tracepoint actions and condition expressions. Use the "tvariable"
1944 command to create, and "info tvariables" to view; see "Trace State
1945 Variables" in the manual for more detail.
1949 GDB now includes an option for defining fast tracepoints, which
1950 targets may implement more efficiently, such as by installing a jump
1951 into the target agent rather than a trap instruction. The resulting
1952 speedup can be by two orders of magnitude or more, although the
1953 tradeoff is that some program locations on some target architectures
1954 might not allow fast tracepoint installation, for instance if the
1955 instruction to be replaced is shorter than the jump. To request a
1956 fast tracepoint, use the "ftrace" command, with syntax identical to
1957 the regular trace command.
1959 ** Disconnected tracing
1961 It is now possible to detach GDB from the target while it is running
1962 a trace experiment, then reconnect later to see how the experiment
1963 is going. In addition, a new variable disconnected-tracing lets you
1964 tell the target agent whether to continue running a trace if the
1965 connection is lost unexpectedly.
1969 GDB now has the ability to save the trace buffer into a file, and
1970 then use that file as a target, similarly to you can do with
1971 corefiles. You can select trace frames, print data that was
1972 collected in them, and use tstatus to display the state of the
1973 tracing run at the moment that it was saved. To create a trace
1974 file, use "tsave <filename>", and to use it, do "target tfile
1977 ** Circular trace buffer
1979 You can ask the target agent to handle the trace buffer as a
1980 circular buffer, discarding the oldest trace frames to make room for
1981 newer ones, by setting circular-trace-buffer to on. This feature may
1982 not be available for all target agents.
1987 The disassemble command, when invoked with two arguments, now requires
1988 the arguments to be comma-separated.
1991 The info variables command now displays variable definitions. Files
1992 which only declare a variable are not shown.
1995 The source command is now capable of sourcing Python scripts.
1996 This feature is dependent on the debugger being build with Python
1999 Related to this enhancement is also the introduction of a new command
2000 "set script-extension" (see below).
2002 * New commands (for set/show, see "New options" below)
2004 record save [<FILENAME>]
2005 Save a file (in core file format) containing the process record
2006 execution log for replay debugging at a later time.
2008 record restore <FILENAME>
2009 Restore the process record execution log that was saved at an
2010 earlier time, for replay debugging.
2012 add-inferior [-copies <N>] [-exec <FILENAME>]
2015 clone-inferior [-copies <N>] [ID]
2016 Make a new inferior ready to execute the same program another
2017 inferior has loaded.
2022 maint info program-spaces
2023 List the program spaces loaded into GDB.
2025 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2026 show remote interrupt-sequence
2027 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2028 as the sequence to the remote target in order to interrupt the execution.
2029 Ctrl-C is a default. Some system prefers BREAK which is high level of
2030 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2031 Magic SysRq g. It is BREAK signal and character 'g'.
2033 set remote interrupt-on-connect [on | off]
2034 show remote interrupt-on-connect
2035 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2036 remote target when gdb connects to it. This is needed when you debug
2039 set remotebreak [on | off]
2041 Deprecated. Use "set/show remote interrupt-sequence" instead.
2043 tvariable $NAME [ = EXP ]
2044 Create or modify a trace state variable.
2047 List trace state variables and their values.
2049 delete tvariable $NAME ...
2050 Delete one or more trace state variables.
2053 Evaluate the given expressions without collecting anything into the
2054 trace buffer. (Valid in tracepoint actions only.)
2056 ftrace FN / FILE:LINE / *ADDR
2057 Define a fast tracepoint at the given function, line, or address.
2059 * New expression syntax
2061 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2062 GDB now parses 0b101010 identically with 42.
2066 set follow-exec-mode new|same
2067 show follow-exec-mode
2068 Control whether GDB reuses the same inferior across an exec call or
2069 creates a new one. This is useful to be able to restart the old
2070 executable after the inferior having done an exec call.
2072 set default-collect EXPR, ...
2073 show default-collect
2074 Define a list of expressions to be collected at each tracepoint.
2075 This is a useful way to ensure essential items are not overlooked,
2076 such as registers or a critical global variable.
2078 set disconnected-tracing
2079 show disconnected-tracing
2080 If set to 1, the target is instructed to continue tracing if it
2081 loses its connection to GDB. If 0, the target is to stop tracing
2084 set circular-trace-buffer
2085 show circular-trace-buffer
2086 If set to on, the target is instructed to use a circular trace buffer
2087 and discard the oldest trace frames instead of stopping the trace due
2088 to a full trace buffer. If set to off, the trace stops when the buffer
2089 fills up. Some targets may not support this.
2091 set script-extension off|soft|strict
2092 show script-extension
2093 If set to "off", the debugger does not perform any script language
2094 recognition, and all sourced files are assumed to be GDB scripts.
2095 If set to "soft" (the default), files are sourced according to
2096 filename extension, falling back to GDB scripts if the first
2098 If set to "strict", files are sourced according to filename extension.
2100 set ada trust-PAD-over-XVS on|off
2101 show ada trust-PAD-over-XVS
2102 If off, activate a workaround against a bug in the debugging information
2103 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2104 the GCC sources for more information about the GNAT encoding and
2105 PAD types in particular). It is always safe to set this option to
2106 off, but this introduces a slight performance penalty. The default
2109 * Python API Improvements
2111 ** GDB provides the new class gdb.LazyString. This is useful in
2112 some pretty-printing cases. The new method gdb.Value.lazy_string
2113 provides a simple way to create objects of this type.
2115 ** The fields returned by gdb.Type.fields now have an
2116 `is_base_class' attribute.
2118 ** The new method gdb.Type.range returns the range of an array type.
2120 ** The new method gdb.parse_and_eval can be used to parse and
2121 evaluate an expression.
2123 * New remote packets
2126 Define a trace state variable.
2129 Get the current value of a trace state variable.
2132 Set desired tracing behavior upon disconnection.
2135 Set the trace buffer to be linear or circular.
2138 Get data about the tracepoints currently in use.
2142 Process record now works correctly with hardware watchpoints.
2144 Multiple bug fixes have been made to the mips-irix port, making it
2145 much more reliable. In particular:
2146 - Debugging threaded applications is now possible again. Previously,
2147 GDB would hang while starting the program, or while waiting for
2148 the program to stop at a breakpoint.
2149 - Attaching to a running process no longer hangs.
2150 - An error occurring while loading a core file has been fixed.
2151 - Changing the value of the PC register now works again. This fixes
2152 problems observed when using the "jump" command, or when calling
2153 a function from GDB, or even when assigning a new value to $pc.
2154 - With the "finish" and "return" commands, the return value for functions
2155 returning a small array is now correctly printed.
2156 - It is now possible to break on shared library code which gets executed
2157 during a shared library init phase (code executed while executing
2158 their .init section). Previously, the breakpoint would have no effect.
2159 - GDB is now able to backtrace through the signal handler for
2160 non-threaded programs.
2162 PIE (Position Independent Executable) programs debugging is now supported.
2163 This includes debugging execution of PIC (Position Independent Code) shared
2164 libraries although for that, it should be possible to run such libraries as an
2167 *** Changes in GDB 7.0
2169 * GDB now has an interface for JIT compilation. Applications that
2170 dynamically generate code can create symbol files in memory and register
2171 them with GDB. For users, the feature should work transparently, and
2172 for JIT developers, the interface is documented in the GDB manual in the
2173 "JIT Compilation Interface" chapter.
2175 * Tracepoints may now be conditional. The syntax is as for
2176 breakpoints; either an "if" clause appended to the "trace" command,
2177 or the "condition" command is available. GDB sends the condition to
2178 the target for evaluation using the same bytecode format as is used
2179 for tracepoint actions.
2181 * The disassemble command now supports: an optional /r modifier, print the
2182 raw instructions in hex as well as in symbolic form, and an optional /m
2183 modifier to print mixed source+assembly.
2185 * Process record and replay
2187 In a architecture environment that supports ``process record and
2188 replay'', ``process record and replay'' target can record a log of
2189 the process execution, and replay it with both forward and reverse
2192 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2193 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2194 set execution-direction {forward|reverse}, for targets that support
2197 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2198 feature is available with a native GDB running on kernel version
2201 * GDB now has support for multi-byte and wide character sets on the
2202 target. Strings whose character type is wchar_t, char16_t, or
2203 char32_t are now correctly printed. GDB supports wide- and unicode-
2204 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2205 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2206 `printf'. This feature requires iconv to work properly; if your
2207 system does not have a working iconv, GDB can use GNU libiconv. See
2208 the installation instructions for more information.
2210 * GDB now supports automatic retrieval of shared library files from
2211 remote targets. To use this feature, specify a system root that begins
2212 with the `remote:' prefix, either via the `set sysroot' command or via
2213 the `--with-sysroot' configure-time option.
2215 * "info sharedlibrary" now takes an optional regex of libraries to show,
2216 and it now reports if a shared library has no debugging information.
2218 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2219 now complete on file names.
2221 * When completing in expressions, gdb will attempt to limit
2222 completions to allowable structure or union fields, where appropriate.
2223 For instance, consider:
2225 # struct example { int f1; double f2; };
2226 # struct example variable;
2229 If the user types TAB at the end of this command line, the available
2230 completions will be "f1" and "f2".
2232 * Inlined functions are now supported. They show up in backtraces, and
2233 the "step", "next", and "finish" commands handle them automatically.
2235 * GDB now supports the token-splicing (##) and stringification (#)
2236 operators when expanding macros. It also supports variable-arity
2239 * GDB now supports inspecting extra signal information, exported by
2240 the new $_siginfo convenience variable. The feature is currently
2241 implemented on linux ARM, i386 and amd64.
2243 * GDB can now display the VFP floating point registers and NEON vector
2244 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2245 can provide these registers (requires Linux 2.6.30 or later). Remote
2246 and simulator targets may also provide them.
2248 * New remote packets
2251 Search memory for a sequence of bytes.
2254 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2255 operation over reliable transport links. Use of this packet is
2256 controlled by the `set remote noack-packet' command.
2259 Kill the process with the specified process ID. Use this in preference
2260 to `k' when multiprocess protocol extensions are supported.
2263 Obtains additional operating system information
2267 Read or write additional signal information.
2269 * Removed remote protocol undocumented extension
2271 An undocumented extension to the remote protocol's `S' stop reply
2272 packet that permited the stub to pass a process id was removed.
2273 Remote servers should use the `T' stop reply packet instead.
2275 * GDB now supports multiple function calling conventions according to the
2276 DWARF-2 DW_AT_calling_convention function attribute.
2278 * The SH target utilizes the aforementioned change to distinguish between gcc
2279 and Renesas calling convention. It also adds the new CLI commands
2280 `set/show sh calling-convention'.
2282 * GDB can now read compressed debug sections, as produced by GNU gold
2283 with the --compress-debug-sections=zlib flag.
2285 * 64-bit core files are now supported on AIX.
2287 * Thread switching is now supported on Tru64.
2289 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2290 which will be allocated using malloc later in program execution.
2292 * The qXfer:libraries:read remote procotol packet now allows passing a
2293 list of section offsets.
2295 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2296 conditions handling signals delivered during attach or thread creation
2297 have also been fixed.
2299 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2300 From the user's standpoint, all unqualified instances of True and False
2301 are treated as the standard definitions, regardless of context.
2303 * GDB now parses C++ symbol and type names more flexibly. For
2306 template<typename T> class C { };
2309 GDB will now correctly handle all of:
2311 ptype C<char const *>
2312 ptype C<char const*>
2313 ptype C<const char *>
2314 ptype C<const char*>
2316 * New features in the GDB remote stub, gdbserver
2318 - The "--wrapper" command-line argument tells gdbserver to use a
2319 wrapper program to launch programs for debugging.
2321 - On PowerPC and S/390 targets, it is now possible to use a single
2322 gdbserver executable to debug both 32-bit and 64-bit programs.
2323 (This requires gdbserver itself to be built as a 64-bit executable.)
2325 - gdbserver uses the new noack protocol mode for TCP connections to
2326 reduce communications latency, if also supported and enabled in GDB.
2328 - Support for the sparc64-linux-gnu target is now included in
2331 - The amd64-linux build of gdbserver now supports debugging both
2332 32-bit and 64-bit programs.
2334 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2335 now support hardware watchpoints, and will use them automatically
2340 GDB now has support for scripting using Python. Whether this is
2341 available is determined at configure time.
2343 New GDB commands can now be written in Python.
2345 * Ada tasking support
2347 Ada tasks can now be inspected in GDB. The following commands have
2351 Print the list of Ada tasks.
2353 Print detailed information about task number N.
2355 Print the task number of the current task.
2357 Switch the context of debugging to task number N.
2359 * Support for user-defined prefixed commands. The "define" command can
2360 add new commands to existing prefixes, e.g. "target".
2362 * Multi-inferior, multi-process debugging.
2364 GDB now has generalized support for multi-inferior debugging. See
2365 "Debugging Multiple Inferiors" in the manual for more information.
2366 Although availability still depends on target support, the command
2367 set is more uniform now. The GNU/Linux specific multi-forks support
2368 has been migrated to this new framework. This implied some user
2369 visible changes; see "New commands" and also "Removed commands"
2372 * Target descriptions can now describe the target OS ABI. See the
2373 "Target Description Format" section in the user manual for more
2376 * Target descriptions can now describe "compatible" architectures
2377 to indicate that the target can execute applications for a different
2378 architecture in addition to those for the main target architecture.
2379 See the "Target Description Format" section in the user manual for
2382 * Multi-architecture debugging.
2384 GDB now includes general supports for debugging applications on
2385 hybrid systems that use more than one single processor architecture
2386 at the same time. Each such hybrid architecture still requires
2387 specific support to be added. The only hybrid architecture supported
2388 in this version of GDB is the Cell Broadband Engine.
2390 * GDB now supports integrated debugging of Cell/B.E. applications that
2391 use both the PPU and SPU architectures. To enable support for hybrid
2392 Cell/B.E. debugging, you need to configure GDB to support both the
2393 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2394 --enable-targets configure option.
2396 * Non-stop mode debugging.
2398 For some targets, GDB now supports an optional mode of operation in
2399 which you can examine stopped threads while other threads continue
2400 to execute freely. This is referred to as non-stop mode, with the
2401 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2402 section in the user manual for more information.
2404 To be able to support remote non-stop debugging, a remote stub needs
2405 to implement the non-stop mode remote protocol extensions, as
2406 described in the "Remote Non-Stop" section of the user manual. The
2407 GDB remote stub, gdbserver, has been adjusted to support these
2408 extensions on linux targets.
2410 * New commands (for set/show, see "New options" below)
2412 catch syscall [NAME(S) | NUMBER(S)]
2413 Catch system calls. Arguments, which should be names of system
2414 calls or their numbers, mean catch only those syscalls. Without
2415 arguments, every syscall will be caught. When the inferior issues
2416 any of the specified syscalls, GDB will stop and announce the system
2417 call, both when it is called and when its call returns. This
2418 feature is currently available with a native GDB running on the
2419 Linux Kernel, under the following architectures: x86, x86_64,
2420 PowerPC and PowerPC64.
2422 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2424 Search memory for a sequence of bytes.
2426 maint set python print-stack
2427 maint show python print-stack
2428 Show a stack trace when an error is encountered in a Python script.
2431 Invoke CODE by passing it to the Python interpreter.
2436 These allow macros to be defined, undefined, and listed
2440 Show operating system information about processes.
2443 List the inferiors currently under GDB's control.
2446 Switch focus to inferior number NUM.
2449 Detach from inferior number NUM.
2452 Kill inferior number NUM.
2456 set spu stop-on-load
2457 show spu stop-on-load
2458 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2460 set spu auto-flush-cache
2461 show spu auto-flush-cache
2462 Control whether to automatically flush the software-managed cache
2463 during Cell/B.E. debugging.
2465 set sh calling-convention
2466 show sh calling-convention
2467 Control the calling convention used when calling SH target functions.
2470 show debug timestamp
2471 Control display of timestamps with GDB debugging output.
2473 set disassemble-next-line
2474 show disassemble-next-line
2475 Control display of disassembled source lines or instructions when
2478 set remote noack-packet
2479 show remote noack-packet
2480 Set/show the use of remote protocol QStartNoAckMode packet. See above
2481 under "New remote packets."
2483 set remote query-attached-packet
2484 show remote query-attached-packet
2485 Control use of remote protocol `qAttached' (query-attached) packet.
2487 set remote read-siginfo-object
2488 show remote read-siginfo-object
2489 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2492 set remote write-siginfo-object
2493 show remote write-siginfo-object
2494 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2497 set remote reverse-continue
2498 show remote reverse-continue
2499 Control use of remote protocol 'bc' (reverse-continue) packet.
2501 set remote reverse-step
2502 show remote reverse-step
2503 Control use of remote protocol 'bs' (reverse-step) packet.
2505 set displaced-stepping
2506 show displaced-stepping
2507 Control displaced stepping mode. Displaced stepping is a way to
2508 single-step over breakpoints without removing them from the debuggee.
2509 Also known as "out-of-line single-stepping".
2512 show debug displaced
2513 Control display of debugging info for displaced stepping.
2515 maint set internal-error
2516 maint show internal-error
2517 Control what GDB does when an internal error is detected.
2519 maint set internal-warning
2520 maint show internal-warning
2521 Control what GDB does when an internal warning is detected.
2526 Use a wrapper program to launch programs for debugging.
2528 set multiple-symbols (all|ask|cancel)
2529 show multiple-symbols
2530 The value of this variable can be changed to adjust the debugger behavior
2531 when an expression or a breakpoint location contains an ambiguous symbol
2532 name (an overloaded function name, for instance).
2534 set breakpoint always-inserted
2535 show breakpoint always-inserted
2536 Keep breakpoints always inserted in the target, as opposed to inserting
2537 them when resuming the target, and removing them when the target stops.
2538 This option can improve debugger performance on slow remote targets.
2540 set arm fallback-mode (arm|thumb|auto)
2541 show arm fallback-mode
2542 set arm force-mode (arm|thumb|auto)
2544 These commands control how ARM GDB determines whether instructions
2545 are ARM or Thumb. The default for both settings is auto, which uses
2546 the current CPSR value for instructions without symbols; previous
2547 versions of GDB behaved as if "set arm fallback-mode arm".
2549 set disable-randomization
2550 show disable-randomization
2551 Standalone programs run with the virtual address space randomization enabled
2552 by default on some platforms. This option keeps the addresses stable across
2553 multiple debugging sessions.
2557 Control whether other threads are stopped or not when some thread hits
2562 Requests that asynchronous execution is enabled in the target, if available.
2563 In this case, it's possible to resume target in the background, and interact
2564 with GDB while the target is running. "show target-async" displays the
2565 current state of asynchronous execution of the target.
2567 set target-wide-charset
2568 show target-wide-charset
2569 The target-wide-charset is the name of the character set that GDB
2570 uses when printing characters whose type is wchar_t.
2572 set tcp auto-retry (on|off)
2574 set tcp connect-timeout
2575 show tcp connect-timeout
2576 These commands allow GDB to retry failed TCP connections to a remote stub
2577 with a specified timeout period; this is useful if the stub is launched
2578 in parallel with GDB but may not be ready to accept connections immediately.
2580 set libthread-db-search-path
2581 show libthread-db-search-path
2582 Control list of directories which GDB will search for appropriate
2585 set schedule-multiple (on|off)
2586 show schedule-multiple
2587 Allow GDB to resume all threads of all processes or only threads of
2588 the current process.
2592 Use more aggressive caching for accesses to the stack. This improves
2593 performance of remote debugging (particularly backtraces) without
2594 affecting correctness.
2596 set interactive-mode (on|off|auto)
2597 show interactive-mode
2598 Control whether GDB runs in interactive mode (on) or not (off).
2599 When in interactive mode, GDB waits for the user to answer all
2600 queries. Otherwise, GDB does not wait and assumes the default
2601 answer. When set to auto (the default), GDB determines which
2602 mode to use based on the stdin settings.
2607 For program forks, this is replaced by the new more generic `info
2608 inferiors' command. To list checkpoints, you can still use the
2609 `info checkpoints' command, which was an alias for the `info forks'
2613 Replaced by the new `inferior' command. To switch between
2614 checkpoints, you can still use the `restart' command, which was an
2615 alias for the `fork' command.
2618 This is removed, since some targets don't have a notion of
2619 processes. To switch between processes, you can still use the
2620 `inferior' command using GDB's own inferior number.
2623 For program forks, this is replaced by the new more generic `kill
2624 inferior' command. To delete a checkpoint, you can still use the
2625 `delete checkpoint' command, which was an alias for the `delete
2629 For program forks, this is replaced by the new more generic `detach
2630 inferior' command. To detach a checkpoint, you can still use the
2631 `detach checkpoint' command, which was an alias for the `detach
2634 * New native configurations
2636 x86/x86_64 Darwin i[34567]86-*-darwin*
2638 x86_64 MinGW x86_64-*-mingw*
2642 Lattice Mico32 lm32-*
2643 x86 DICOS i[34567]86-*-dicos*
2644 x86_64 DICOS x86_64-*-dicos*
2647 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2648 (mingw32ce) debugging.
2654 These commands were actually not implemented on any target.
2656 *** Changes in GDB 6.8
2658 * New native configurations
2660 NetBSD/hppa hppa*-*netbsd*
2661 Xtensa GNU/Linux xtensa*-*-linux*
2665 NetBSD/hppa hppa*-*-netbsd*
2666 Xtensa GNU/Lunux xtensa*-*-linux*
2668 * Change in command line behavior -- corefiles vs. process ids.
2670 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2671 attaching to process NUMBER fails, GDB no longer attempts to open a
2672 core file named NUMBER. Attaching to a program using the -c option
2673 is no longer supported. Instead, use the '-p' or '--pid' options.
2675 * GDB can now be built as a native debugger for debugging Windows x86
2676 (mingw32) Portable Executable (PE) programs.
2678 * Pending breakpoints no longer change their number when their address
2681 * GDB now supports breakpoints with multiple locations,
2682 including breakpoints on C++ constructors, inside C++ templates,
2683 and in inlined functions.
2685 * GDB's ability to debug optimized code has been improved. GDB more
2686 accurately identifies function bodies and lexical blocks that occupy
2687 more than one contiguous range of addresses.
2689 * Target descriptions can now describe registers for PowerPC.
2691 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2692 registers on PowerPC targets.
2694 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2695 targets even when the libthread_db library is not available.
2697 * The GDB remote stub, gdbserver, now supports the new file transfer
2698 commands (remote put, remote get, and remote delete).
2700 * The GDB remote stub, gdbserver, now supports run and attach in
2701 extended-remote mode.
2703 * hppa*64*-*-hpux11* target broken
2704 The debugger is unable to start a program and fails with the following
2705 error: "Error trying to get information about dynamic linker".
2706 The gdb-6.7 release is also affected.
2708 * GDB now supports the --enable-targets= configure option to allow
2709 building a single GDB executable that supports multiple remote
2710 target architectures.
2712 * GDB now supports debugging C and C++ programs which use the
2713 Decimal Floating Point extension. In addition, the PowerPC target
2714 now has a set of pseudo-registers to inspect decimal float values
2715 stored in two consecutive float registers.
2717 * The -break-insert MI command can optionally create pending
2720 * Improved support for debugging Ada
2721 Many improvements to the Ada language support have been made. These
2723 - Better support for Ada2005 interface types
2724 - Improved handling of arrays and slices in general
2725 - Better support for Taft-amendment types
2726 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2728 - Improved command completion in Ada
2731 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2736 set print frame-arguments (all|scalars|none)
2737 show print frame-arguments
2738 The value of this variable can be changed to control which argument
2739 values should be printed by the debugger when displaying a frame.
2744 Transfer files to and from a remote target, and delete remote files.
2751 Transfer files to and from a remote target, and delete remote files.
2753 * New remote packets
2760 Open, close, read, write, and delete files on the remote system.
2763 Attach to an existing process on the remote system, in extended-remote
2767 Run a new process on the remote system, in extended-remote mode.
2769 *** Changes in GDB 6.7
2771 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2772 bfd, libiberty and opcodes, as revealed by static analysis donated by
2773 Coverity, Inc. (http://scan.coverity.com).
2775 * When looking up multiply-defined global symbols, GDB will now prefer the
2776 symbol definition in the current shared library if it was built using the
2777 -Bsymbolic linker option.
2779 * When the Text User Interface (TUI) is not configured, GDB will now
2780 recognize the -tui command-line option and print a message that the TUI
2783 * The GDB remote stub, gdbserver, now has lower overhead for high
2784 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2786 * GDB for MIPS targets now autodetects whether a remote target provides
2787 32-bit or 64-bit register values.
2789 * Support for C++ member pointers has been improved.
2791 * GDB now understands XML target descriptions, which specify the
2792 target's overall architecture. GDB can read a description from
2793 a local file or over the remote serial protocol.
2795 * Vectors of single-byte data use a new integer type which is not
2796 automatically displayed as character or string data.
2798 * The /s format now works with the print command. It displays
2799 arrays of single-byte integers and pointers to single-byte integers
2802 * Target descriptions can now describe target-specific registers,
2803 for architectures which have implemented the support (currently
2804 only ARM, M68K, and MIPS).
2806 * GDB and the GDB remote stub, gdbserver, now support the XScale
2809 * The GDB remote stub, gdbserver, has been updated to support
2810 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2811 has been rewritten to use the standard GDB remote protocol.
2813 * GDB can now step into C++ functions which are called through thunks.
2815 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2817 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2818 layout. It also supports a TextSeg= and DataSeg= response when only
2819 segment base addresses (rather than offsets) are available.
2821 * The /i format now outputs any trailing branch delay slot instructions
2822 immediately following the last instruction within the count specified.
2824 * The GDB remote protocol "T" stop reply packet now supports a
2825 "library" response. Combined with the new "qXfer:libraries:read"
2826 packet, this response allows GDB to debug shared libraries on targets
2827 where the operating system manages the list of loaded libraries (e.g.
2828 Windows and SymbianOS).
2830 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2831 (DLLs) on Windows and Windows CE targets.
2833 * GDB now supports a faster verification that a .debug file matches its binary
2834 according to its build-id signature, if the signature is present.
2840 Enable or disable hardware flow control (RTS/CTS) on the serial port
2841 when debugging using remote targets.
2843 set mem inaccessible-by-default
2844 show mem inaccessible-by-default
2845 If the target supplies a memory map, for instance via the remote
2846 protocol's "qXfer:memory-map:read" packet, setting this variable
2847 prevents GDB from accessing memory outside the memory map. This
2848 is useful for targets with memory mapped registers or which react
2849 badly to accesses of unmapped address space.
2851 set breakpoint auto-hw
2852 show breakpoint auto-hw
2853 If the target supplies a memory map, for instance via the remote
2854 protocol's "qXfer:memory-map:read" packet, setting this variable
2855 lets GDB use hardware breakpoints automatically for memory regions
2856 where it can not use software breakpoints. This covers both the
2857 "break" command and internal breakpoints used for other commands
2858 including "next" and "finish".
2861 catch exception unhandled
2862 Stop the program execution when Ada exceptions are raised.
2865 Stop the program execution when an Ada assertion failed.
2869 Set an alternate system root for target files. This is a more
2870 general version of "set solib-absolute-prefix", which is now
2871 an alias to "set sysroot".
2874 Provide extended SPU facility status information. This set of
2875 commands is available only when debugging the Cell/B.E. SPU
2878 * New native configurations
2880 OpenBSD/sh sh*-*openbsd*
2883 unset tdesc filename
2885 Use the specified local file as an XML target description, and do
2886 not query the target for its built-in description.
2890 OpenBSD/sh sh*-*-openbsd*
2891 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2892 Toshiba Media Processor mep-elf
2894 * New remote packets
2897 Ignore the specified signals; pass them directly to the debugged program
2898 without stopping other threads or reporting them to GDB.
2900 qXfer:features:read:
2901 Read an XML target description from the target, which describes its
2906 Read or write contents of an spufs file on the target system. These
2907 packets are available only on the Cell/B.E. SPU architecture.
2909 qXfer:libraries:read:
2910 Report the loaded shared libraries. Combined with new "T" packet
2911 response, this packet allows GDB to debug shared libraries on
2912 targets where the operating system manages the list of loaded
2913 libraries (e.g. Windows and SymbianOS).
2917 Support for these obsolete configurations has been removed.
2925 i[34567]86-*-lynxos*
2926 i[34567]86-*-netware*
2927 i[34567]86-*-sco3.2v5*
2928 i[34567]86-*-sco3.2v4*
2930 i[34567]86-*-sysv4.2*
2933 i[34567]86-*-unixware2*
2934 i[34567]86-*-unixware*
2943 * Other removed features
2950 Various m68k-only ROM monitors.
2957 Various Renesas ROM monitors and debugging interfaces for SH and
2962 Support for a Macraigor serial interface to on-chip debugging.
2963 GDB does not directly support the newer parallel or USB
2968 A debug information format. The predecessor to DWARF 2 and
2969 DWARF 3, which are still supported.
2971 Support for the HP aCC compiler on HP-UX/PA-RISC
2973 SOM-encapsulated symbolic debugging information, automatic
2974 invocation of pxdb, and the aCC custom C++ ABI. This does not
2975 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2976 with aCC can still be debugged on an assembly level.
2978 MIPS ".pdr" sections
2980 A MIPS-specific format used to describe stack frame layout
2981 in debugging information.
2985 GDB could work with an older version of Guile to debug
2986 the interpreter and Scheme programs running in it.
2988 set mips stack-arg-size
2989 set mips saved-gpreg-size
2991 Use "set mips abi" to control parameter passing for MIPS.
2993 *** Changes in GDB 6.6
2998 Cell Broadband Engine SPU spu-elf
3000 * GDB can now be configured as a cross-debugger targeting native Windows
3001 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3002 running on a Windows system over TCP/IP to debug Windows programs.
3004 * The GDB remote stub, gdbserver, has been updated to support Windows and
3005 Cygwin debugging. Both single-threaded and multi-threaded programs are
3008 * The "set trust-readonly-sections" command works again. This command was
3009 broken in GDB 6.3, 6.4, and 6.5.
3011 * The "load" command now supports writing to flash memory, if the remote
3012 stub provides the required support.
3014 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3015 longer requires symbolic debug information (e.g. DWARF-2).
3020 unset substitute-path
3021 show substitute-path
3022 Manage a list of substitution rules that GDB uses to rewrite the name
3023 of the directories where the sources are located. This can be useful
3024 for instance when the sources were moved to a different location
3025 between compilation and debugging.
3029 Print each CLI command as it is executed. Each command is prefixed with
3030 a number of `+' symbols representing the nesting depth.
3031 The source command now has a `-v' option to enable the same feature.
3035 The ARM Demon monitor support (RDP protocol, "target rdp").
3037 Kernel Object Display, an embedded debugging feature which only worked with
3038 an obsolete version of Cisco IOS.
3040 The 'set download-write-size' and 'show download-write-size' commands.
3042 * New remote packets
3045 Tell a stub about GDB client features, and request remote target features.
3046 The first feature implemented is PacketSize, which allows the target to
3047 specify the size of packets it can handle - to minimize the number of
3048 packets required and improve performance when connected to a remote
3052 Fetch an OS auxilliary vector from the remote stub. This packet is a
3053 more efficient replacement for qPart:auxv:read.
3055 qXfer:memory-map:read:
3056 Fetch a memory map from the remote stub, including information about
3057 RAM, ROM, and flash memory devices.
3062 Erase and program a flash memory device.
3064 * Removed remote packets
3067 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3068 used it, and only gdbserver implemented it.
3070 *** Changes in GDB 6.5
3074 Renesas M32C/M16C m32c-elf
3076 Morpho Technologies ms1 ms1-elf
3080 init-if-undefined Initialize a convenience variable, but
3081 only if it doesn't already have a value.
3083 The following commands are presently only implemented for native GNU/Linux:
3085 checkpoint Save a snapshot of the program state.
3087 restart <n> Return the program state to a
3088 previously saved state.
3090 info checkpoints List currently saved checkpoints.
3092 delete-checkpoint <n> Delete a previously saved checkpoint.
3094 set|show detach-on-fork Tell gdb whether to detach from a newly
3095 forked process, or to keep debugging it.
3097 info forks List forks of the user program that
3098 are available to be debugged.
3100 fork <n> Switch to debugging one of several
3101 forks of the user program that are
3102 available to be debugged.
3104 delete-fork <n> Delete a fork from the list of forks
3105 that are available to be debugged (and
3106 kill the forked process).
3108 detach-fork <n> Delete a fork from the list of forks
3109 that are available to be debugged (and
3110 allow the process to continue).
3114 Morpho Technologies ms2 ms1-elf
3116 * Improved Windows host support
3118 GDB now builds as a cross debugger hosted on i686-mingw32, including
3119 native console support, and remote communications using either
3120 network sockets or serial ports.
3122 * Improved Modula-2 language support
3124 GDB can now print most types in the Modula-2 syntax. This includes:
3125 basic types, set types, record types, enumerated types, range types,
3126 pointer types and ARRAY types. Procedure var parameters are correctly
3127 printed and hexadecimal addresses and character constants are also
3128 written in the Modula-2 syntax. Best results can be obtained by using
3129 GNU Modula-2 together with the -gdwarf-2 command line option.
3133 The ARM rdi-share module.
3135 The Netware NLM debug server.
3137 *** Changes in GDB 6.4
3139 * New native configurations
3141 OpenBSD/arm arm*-*-openbsd*
3142 OpenBSD/mips64 mips64-*-openbsd*
3146 Morpho Technologies ms1 ms1-elf
3148 * New command line options
3150 --batch-silent As for --batch, but totally silent.
3151 --return-child-result The debugger will exist with the same value
3152 the child (debugged) program exited with.
3153 --eval-command COMMAND, -ex COMMAND
3154 Execute a single GDB CLI command. This may be
3155 specified multiple times and in conjunction
3156 with the --command (-x) option.
3158 * Deprecated commands removed
3160 The following commands, that were deprecated in 2000, have been
3164 set|show arm disassembly-flavor set|show arm disassembler
3165 othernames set arm disassembler
3166 set|show remotedebug set|show debug remote
3167 set|show archdebug set|show debug arch
3168 set|show eventdebug set|show debug event
3171 * New BSD user-level threads support
3173 It is now possible to debug programs using the user-level threads
3174 library on OpenBSD and FreeBSD. Currently supported (target)
3177 FreeBSD/amd64 x86_64-*-freebsd*
3178 FreeBSD/i386 i386-*-freebsd*
3179 OpenBSD/i386 i386-*-openbsd*
3181 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3182 are not yet supported.
3184 * New support for Matsushita MN10300 w/sim added
3185 (Work in progress). mn10300-elf.
3187 * REMOVED configurations and files
3189 VxWorks and the XDR protocol *-*-vxworks
3190 Motorola MCORE mcore-*-*
3191 National Semiconductor NS32000 ns32k-*-*
3193 * New "set print array-indexes" command
3195 After turning this setting "on", GDB prints the index of each element
3196 when displaying arrays. The default is "off" to preserve the previous
3199 * VAX floating point support
3201 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3203 * User-defined command support
3205 In addition to using $arg0..$arg9 for argument passing, it is now possible
3206 to use $argc to determine now many arguments have been passed. See the
3207 section on user-defined commands in the user manual for more information.
3209 *** Changes in GDB 6.3:
3211 * New command line option
3213 GDB now accepts -l followed by a number to set the timeout for remote
3216 * GDB works with GCC -feliminate-dwarf2-dups
3218 GDB now supports a more compact representation of DWARF-2 debug
3219 information using DW_FORM_ref_addr references. These are produced
3220 by GCC with the option -feliminate-dwarf2-dups and also by some
3221 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3222 to use -feliminate-dwarf2-dups.
3224 * Internationalization
3226 When supported by the host system, GDB will be built with
3227 internationalization (libintl). The task of marking up the sources is
3228 continued, we're looking forward to our first translation.
3232 Initial support for debugging programs compiled with the GNAT
3233 implementation of the Ada programming language has been integrated
3234 into GDB. In this release, support is limited to expression evaluation.
3236 * New native configurations
3238 GNU/Linux/m32r m32r-*-linux-gnu
3242 GDB's remote protocol now includes support for the 'p' packet. This
3243 packet is used to fetch individual registers from a remote inferior.
3245 * END-OF-LIFE registers[] compatibility module
3247 GDB's internal register infrastructure has been completely rewritten.
3248 The new infrastructure making possible the implementation of key new
3249 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3252 GDB 6.3 will be the last release to include the the registers[]
3253 compatibility module that allowed out-of-date configurations to
3254 continue to work. This change directly impacts the following
3264 powerpc bdm protocol
3266 Unless there is activity to revive these configurations, they will be
3267 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3269 * OBSOLETE configurations and files
3271 Configurations that have been declared obsolete in this release have
3272 been commented out. Unless there is activity to revive these
3273 configurations, the next release of GDB will have their sources
3274 permanently REMOVED.
3283 *** Changes in GDB 6.2.1:
3285 * MIPS `break main; run' gave an heuristic-fence-post warning
3287 When attempting to run even a simple program, a warning about
3288 heuristic-fence-post being hit would be reported. This problem has
3291 * MIPS IRIX 'long double' crashed GDB
3293 When examining a long double variable, GDB would get a segmentation
3294 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3295 IRIX long double values).
3299 A bug in the VAX stack code was causing problems with the "next"
3300 command. This problem has been fixed.
3302 *** Changes in GDB 6.2:
3304 * Fix for ``many threads''
3306 On GNU/Linux systems that use the NPTL threads library, a program
3307 rapidly creating and deleting threads would confuse GDB leading to the
3310 ptrace: No such process.
3311 thread_db_get_info: cannot get thread info: generic error
3313 This problem has been fixed.
3315 * "-async" and "-noasync" options removed.
3317 Support for the broken "-noasync" option has been removed (it caused
3320 * New ``start'' command.
3322 This command runs the program until the begining of the main procedure.
3324 * New BSD Kernel Data Access Library (libkvm) interface
3326 Using ``target kvm'' it is now possible to debug kernel core dumps and
3327 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3328 platforms. Currently supported (native-only) configurations are:
3330 FreeBSD/amd64 x86_64-*-freebsd*
3331 FreeBSD/i386 i?86-*-freebsd*
3332 NetBSD/i386 i?86-*-netbsd*
3333 NetBSD/m68k m68*-*-netbsd*
3334 NetBSD/sparc sparc-*-netbsd*
3335 OpenBSD/amd64 x86_64-*-openbsd*
3336 OpenBSD/i386 i?86-*-openbsd*
3337 OpenBSD/m68k m68*-openbsd*
3338 OpenBSD/sparc sparc-*-openbsd*
3340 * Signal trampoline code overhauled
3342 Many generic problems with GDB's signal handling code have been fixed.
3343 These include: backtraces through non-contiguous stacks; recognition
3344 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3345 call; backtrace through a signal trampoline; step into and out of
3346 signal handlers; and single-stepping in the signal trampoline.
3348 Please note that kernel bugs are a limiting factor here. These
3349 features have been shown to work on an s390 GNU/Linux system that
3350 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3352 * Cygwin support for DWARF 2 added.
3354 * New native configurations
3356 GNU/Linux/hppa hppa*-*-linux*
3357 OpenBSD/hppa hppa*-*-openbsd*
3358 OpenBSD/m68k m68*-*-openbsd*
3359 OpenBSD/m88k m88*-*-openbsd*
3360 OpenBSD/powerpc powerpc-*-openbsd*
3361 NetBSD/vax vax-*-netbsd*
3362 OpenBSD/vax vax-*-openbsd*
3364 * END-OF-LIFE frame compatibility module
3366 GDB's internal frame infrastructure has been completely rewritten.
3367 The new infrastructure making it possible to support key new features
3368 including DWARF 2 Call Frame Information. To aid in the task of
3369 migrating old configurations to this new infrastructure, a
3370 compatibility module, that allowed old configurations to continue to
3371 work, was also included.
3373 GDB 6.2 will be the last release to include this frame compatibility
3374 module. This change directly impacts the following configurations:
3384 Unless there is activity to revive these configurations, they will be
3385 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3387 * REMOVED configurations and files
3389 Sun 3, running SunOS 3 m68*-*-sunos3*
3390 Sun 3, running SunOS 4 m68*-*-sunos4*
3391 Sun 2, running SunOS 3 m68000-*-sunos3*
3392 Sun 2, running SunOS 4 m68000-*-sunos4*
3393 Motorola 680x0 running LynxOS m68*-*-lynxos*
3394 AT&T 3b1/Unix pc m68*-att-*
3395 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3396 decstation mips-dec-* mips-little-*
3397 riscos mips-*-riscos* mips-*-sysv*
3398 sonymips mips-sony-*
3399 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3401 *** Changes in GDB 6.1.1:
3403 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3405 The TUI (Text-mode User Interface) is now built as part of a default
3406 GDB configuration. It is enabled by either selecting the TUI with the
3407 command line option "-i=tui" or by running the separate "gdbtui"
3408 program. For more information on the TUI, see the manual "Debugging
3411 * Pending breakpoint support (also included in GDB 6.1)
3413 Support has been added to allow you to specify breakpoints in shared
3414 libraries that have not yet been loaded. If a breakpoint location
3415 cannot be found, and the "breakpoint pending" option is set to auto,
3416 GDB queries you if you wish to make the breakpoint pending on a future
3417 shared-library load. If and when GDB resolves the breakpoint symbol,
3418 the pending breakpoint is removed as one or more regular breakpoints
3421 Pending breakpoints are very useful for GCJ Java debugging.
3423 * Fixed ISO-C build problems
3425 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3426 non ISO-C code that stopped them being built using a more strict ISO-C
3427 compiler (e.g., IBM's C compiler).
3429 * Fixed build problem on IRIX 5
3431 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3432 wasn't able to compile compile on an IRIX 5 system.
3434 * Added execute permission to gdb/gdbserver/configure
3436 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3437 permission. This bug would cause configure to fail on a number of
3438 systems (Solaris, IRIX). Ref: server/519.
3440 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3442 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3443 has been updated to use constant array sizes.
3445 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3447 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3448 its generated DWARF Call Frame Info. This encoding was causing GDB to
3449 panic, that panic has been fixed. Ref: gdb/1628.
3451 * Fixed a problem when examining parameters in shared library code.
3453 When examining parameters in optimized shared library code generated
3454 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3455 not available''. GDB now correctly displays the variable's value.
3457 *** Changes in GDB 6.1:
3459 * Removed --with-mmalloc
3461 Support for the mmalloc memory manager has been removed, as it
3462 conflicted with the internal gdb byte cache.
3464 * Changes in AMD64 configurations
3466 The AMD64 target now includes the %cs and %ss registers. As a result
3467 the AMD64 remote protocol has changed; this affects the floating-point
3468 and SSE registers. If you rely on those registers for your debugging,
3469 you should upgrade gdbserver on the remote side.
3471 * Revised SPARC target
3473 The SPARC target has been completely revised, incorporating the
3474 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3475 support for LynxOS and SunOS 4 has been dropped. Calling functions
3476 from within GDB on operating systems with a non-executable stack
3477 (Solaris, OpenBSD) now works.
3481 GDB has a new C++ demangler which does a better job on the mangled
3482 names generated by current versions of g++. It also runs faster, so
3483 with this and other changes gdb should now start faster on large C++
3486 * DWARF 2 Location Expressions
3488 GDB support for location expressions has been extended to support function
3489 arguments and frame bases. Older versions of GDB could crash when they
3492 * C++ nested types and namespaces
3494 GDB's support for nested types and namespaces in C++ has been
3495 improved, especially if you use the DWARF 2 debugging format. (This
3496 is the default for recent versions of GCC on most platforms.)
3497 Specifically, if you have a class "Inner" defined within a class or
3498 namespace "Outer", then GDB realizes that the class's name is
3499 "Outer::Inner", not simply "Inner". This should greatly reduce the
3500 frequency of complaints about not finding RTTI symbols. In addition,
3501 if you are stopped at inside of a function defined within a namespace,
3502 GDB modifies its name lookup accordingly.
3504 * New native configurations
3506 NetBSD/amd64 x86_64-*-netbsd*
3507 OpenBSD/amd64 x86_64-*-openbsd*
3508 OpenBSD/alpha alpha*-*-openbsd*
3509 OpenBSD/sparc sparc-*-openbsd*
3510 OpenBSD/sparc64 sparc64-*-openbsd*
3512 * New debugging protocols
3514 M32R with SDI protocol m32r-*-elf*
3516 * "set prompt-escape-char" command deleted.
3518 The command "set prompt-escape-char" has been deleted. This command,
3519 and its very obscure effet on GDB's prompt, was never documented,
3520 tested, nor mentioned in the NEWS file.
3522 * OBSOLETE configurations and files
3524 Configurations that have been declared obsolete in this release have
3525 been commented out. Unless there is activity to revive these
3526 configurations, the next release of GDB will have their sources
3527 permanently REMOVED.
3529 Sun 3, running SunOS 3 m68*-*-sunos3*
3530 Sun 3, running SunOS 4 m68*-*-sunos4*
3531 Sun 2, running SunOS 3 m68000-*-sunos3*
3532 Sun 2, running SunOS 4 m68000-*-sunos4*
3533 Motorola 680x0 running LynxOS m68*-*-lynxos*
3534 AT&T 3b1/Unix pc m68*-att-*
3535 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3536 decstation mips-dec-* mips-little-*
3537 riscos mips-*-riscos* mips-*-sysv*
3538 sonymips mips-sony-*
3539 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3541 * REMOVED configurations and files
3543 SGI Irix-4.x mips-sgi-irix4 or iris4
3544 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3545 Z8000 simulator z8k-zilog-none or z8ksim
3546 Matsushita MN10200 w/simulator mn10200-*-*
3547 H8/500 simulator h8500-hitachi-hms or h8500hms
3548 HP/PA running BSD hppa*-*-bsd*
3549 HP/PA running OSF/1 hppa*-*-osf*
3550 HP/PA Pro target hppa*-*-pro*
3551 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3552 386BSD i[3456]86-*-bsd*
3553 Sequent family i[3456]86-sequent-sysv4*
3554 i[3456]86-sequent-sysv*
3555 i[3456]86-sequent-bsd*
3556 SPARC running LynxOS sparc-*-lynxos*
3557 SPARC running SunOS 4 sparc-*-sunos4*
3558 Tsqware Sparclet sparclet-*-*
3559 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3561 *** Changes in GDB 6.0:
3565 Support for debugging the Objective-C programming language has been
3566 integrated into GDB.
3568 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3570 DWARF 2's Call Frame Information makes available compiler generated
3571 information that more exactly describes the program's run-time stack.
3572 By using this information, GDB is able to provide more robust stack
3575 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3576 have been updated to use a new backtrace mechanism which includes
3577 DWARF 2 CFI support.
3581 GDB's remote protocol has been extended to include support for hosted
3582 file I/O (where the remote target uses GDB's file system). See GDB's
3583 remote protocol documentation for details.
3585 * All targets using the new architecture framework.
3587 All of GDB's targets have been updated to use the new internal
3588 architecture framework. The way is now open for future GDB releases
3589 to include cross-architecture native debugging support (i386 on amd64,
3592 * GNU/Linux's Thread Local Storage (TLS)
3594 GDB now includes support for for the GNU/Linux implementation of
3595 per-thread variables.
3597 * GNU/Linux's Native POSIX Thread Library (NPTL)
3599 GDB's thread code has been updated to work with either the new
3600 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3602 * Separate debug info.
3604 GDB, in conjunction with BINUTILS, now supports a mechanism for
3605 automatically loading debug information from a separate file. Instead
3606 of shipping full debug and non-debug versions of system libraries,
3607 system integrators can now instead ship just the stripped libraries
3608 and optional debug files.
3610 * DWARF 2 Location Expressions
3612 DWARF 2 Location Expressions allow the compiler to more completely
3613 describe the location of variables (even in optimized code) to the
3616 GDB now includes preliminary support for location expressions (support
3617 for DW_OP_piece is still missing).
3621 A number of long standing bugs that caused GDB to die while starting a
3622 Java application have been fixed. GDB's Java support is now
3623 considered "useable".
3625 * GNU/Linux support for fork, vfork, and exec.
3627 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3628 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3631 * GDB supports logging output to a file
3633 There are two new commands, "set logging" and "show logging", which can be
3634 used to capture GDB's output to a file.
3636 * The meaning of "detach" has changed for gdbserver
3638 The "detach" command will now resume the application, as documented. To
3639 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3642 * d10v, m68hc11 `regs' command deprecated
3644 The `info registers' command has been updated so that it displays the
3645 registers using a format identical to the old `regs' command.
3649 A new command, "maint set profile on/off", has been added. This command can
3650 be used to enable or disable profiling while running GDB, to profile a
3651 session or a set of commands. In addition there is a new configure switch,
3652 "--enable-profiling", which will cause GDB to be compiled with profiling
3653 data, for more informative profiling results.
3655 * Default MI syntax changed to "mi2".
3657 The default MI (machine interface) syntax, enabled by the command line
3658 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3659 "mi1", can be enabled by specifying the option "-i=mi1".
3661 Support for the original "mi0" syntax (included in GDB 5.0) has been
3664 Fix for gdb/192: removed extraneous space when displaying frame level.
3665 Fix for gdb/672: update changelist is now output in mi list format.
3666 Fix for gdb/702: a -var-assign that updates the value now shows up
3667 in a subsequent -var-update.
3669 * New native configurations.
3671 FreeBSD/amd64 x86_64-*-freebsd*
3673 * Multi-arched targets.
3675 HP/PA HPUX11 hppa*-*-hpux*
3676 Renesas M32R/D w/simulator m32r-*-elf*
3678 * OBSOLETE configurations and files
3680 Configurations that have been declared obsolete in this release have
3681 been commented out. Unless there is activity to revive these
3682 configurations, the next release of GDB will have their sources
3683 permanently REMOVED.
3685 Z8000 simulator z8k-zilog-none or z8ksim
3686 Matsushita MN10200 w/simulator mn10200-*-*
3687 H8/500 simulator h8500-hitachi-hms or h8500hms
3688 HP/PA running BSD hppa*-*-bsd*
3689 HP/PA running OSF/1 hppa*-*-osf*
3690 HP/PA Pro target hppa*-*-pro*
3691 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3692 Sequent family i[3456]86-sequent-sysv4*
3693 i[3456]86-sequent-sysv*
3694 i[3456]86-sequent-bsd*
3695 Tsqware Sparclet sparclet-*-*
3696 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3698 * REMOVED configurations and files
3701 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3702 IBM AIX PS/2 i[3456]86-*-aix
3703 i386 running Mach 3.0 i[3456]86-*-mach3*
3704 i386 running Mach i[3456]86-*-mach*
3705 i386 running OSF/1 i[3456]86-*osf1mk*
3706 HP/Apollo 68k Family m68*-apollo*-sysv*,
3708 m68*-hp-bsd*, m68*-hp-hpux*
3709 Argonaut Risc Chip (ARC) arc-*-*
3710 Mitsubishi D30V d30v-*-*
3711 Fujitsu FR30 fr30-*-elf*
3712 OS/9000 i[34]86-*-os9k
3713 I960 with MON960 i960-*-coff
3715 * MIPS $fp behavior changed
3717 The convenience variable $fp, for the MIPS, now consistently returns
3718 the address of the current frame's base. Previously, depending on the
3719 context, $fp could refer to either $sp or the current frame's base
3720 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3721 The GNU Source-Level Debugger''.
3723 *** Changes in GDB 5.3:
3725 * GNU/Linux shared library multi-threaded performance improved.
3727 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3728 `/proc', in preference to `ptrace' for memory reads. This may result
3729 in an improvement in the start-up time of multi-threaded, shared
3730 library applications when run under GDB. One GDB user writes: ``loads
3731 shared libs like mad''.
3733 * ``gdbserver'' now supports multi-threaded applications on some targets
3735 Support for debugging multi-threaded applications which use
3736 the GNU/Linux LinuxThreads package has been added for
3737 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3738 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3740 * GDB now supports C/C++ preprocessor macros.
3742 GDB now expands preprocessor macro invocations in C/C++ expressions,
3743 and provides various commands for showing macro definitions and how
3746 The new command `macro expand EXPRESSION' expands any macro
3747 invocations in expression, and shows the result.
3749 The new command `show macro MACRO-NAME' shows the definition of the
3750 macro named MACRO-NAME, and where it was defined.
3752 Most compilers don't include information about macros in the debugging
3753 information by default. In GCC 3.1, for example, you need to compile
3754 your program with the options `-gdwarf-2 -g3'. If the macro
3755 information is present in the executable, GDB will read it.
3757 * Multi-arched targets.
3759 DEC Alpha (partial) alpha*-*-*
3760 DEC VAX (partial) vax-*-*
3762 National Semiconductor NS32000 (partial) ns32k-*-*
3763 Motorola 68000 (partial) m68k-*-*
3764 Motorola MCORE mcore-*-*
3768 Fujitsu FRV architecture added by Red Hat frv*-*-*
3771 * New native configurations
3773 Alpha NetBSD alpha*-*-netbsd*
3774 SH NetBSD sh*-*-netbsdelf*
3775 MIPS NetBSD mips*-*-netbsd*
3776 UltraSPARC NetBSD sparc64-*-netbsd*
3778 * OBSOLETE configurations and files
3780 Configurations that have been declared obsolete in this release have
3781 been commented out. Unless there is activity to revive these
3782 configurations, the next release of GDB will have their sources
3783 permanently REMOVED.
3785 Mitsubishi D30V d30v-*-*
3786 OS/9000 i[34]86-*-os9k
3787 IBM AIX PS/2 i[3456]86-*-aix
3788 Fujitsu FR30 fr30-*-elf*
3789 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3790 Argonaut Risc Chip (ARC) arc-*-*
3791 i386 running Mach 3.0 i[3456]86-*-mach3*
3792 i386 running Mach i[3456]86-*-mach*
3793 i386 running OSF/1 i[3456]86-*osf1mk*
3794 HP/Apollo 68k Family m68*-apollo*-sysv*,
3796 m68*-hp-bsd*, m68*-hp-hpux*
3797 I960 with MON960 i960-*-coff
3799 * OBSOLETE languages
3801 CHILL, a Pascal like language used by telecommunications companies.
3803 * REMOVED configurations and files
3805 AMD 29k family via UDI a29k-amd-udi, udi29k
3806 A29K VxWorks a29k-*-vxworks
3807 AMD 29000 embedded, using EBMON a29k-none-none
3808 AMD 29000 embedded with COFF a29k-none-coff
3809 AMD 29000 embedded with a.out a29k-none-aout
3811 testsuite/gdb.hp/gdb.threads-hp/ directory
3813 * New command "set max-user-call-depth <nnn>"
3815 This command allows the user to limit the call depth of user-defined
3816 commands. The default is 1024.
3818 * Changes in FreeBSD/i386 native debugging.
3820 Support for the "generate-core-file" has been added.
3822 * New commands "dump", "append", and "restore".
3824 These commands allow data to be copied from target memory
3825 to a bfd-format or binary file (dump and append), and back
3826 from a file into memory (restore).
3828 * Improved "next/step" support on multi-processor Alpha Tru64.
3830 The previous single-step mechanism could cause unpredictable problems,
3831 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3832 of a software single-step mechanism prevents this.
3834 *** Changes in GDB 5.2.1:
3842 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3843 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3844 Fix, by Joel Brobecker imported from mainline.
3846 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3847 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3848 Fix, by Fred Fish, imported from mainline.
3850 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3851 Surprisingly enough, it works now.
3852 By Michal Ludvig, imported from mainline.
3854 i386 hardware watchpoint support:
3855 avoid misses on second run for some targets.
3856 By Pierre Muller, imported from mainline.
3858 *** Changes in GDB 5.2:
3860 * New command "set trust-readonly-sections on[off]".
3862 This command is a hint that tells gdb that read-only sections
3863 really are read-only (ie. that their contents will not change).
3864 In this mode, gdb will go to the object file rather than the
3865 target to read memory from read-only sections (such as ".text").
3866 This can be a significant performance improvement on some
3867 (notably embedded) targets.
3869 * New command "generate-core-file" (or "gcore").
3871 This new gdb command allows the user to drop a core file of the child
3872 process state at any time. So far it's been implemented only for
3873 GNU/Linux and Solaris, but should be relatively easily ported to other
3874 hosts. Argument is core file name (defaults to core.<pid>).
3876 * New command line option
3878 GDB now accepts --pid or -p followed by a process id.
3880 * Change in command line behavior -- corefiles vs. process ids.
3882 There is a subtle behavior in the way in which GDB handles
3883 command line arguments. The first non-flag argument is always
3884 a program to debug, but the second non-flag argument may either
3885 be a corefile or a process id. Previously, GDB would attempt to
3886 open the second argument as a corefile, and if that failed, would
3887 issue a superfluous error message and then attempt to attach it as
3888 a process. Now, if the second argument begins with a non-digit,
3889 it will be treated as a corefile. If it begins with a digit,
3890 GDB will attempt to attach it as a process, and if no such process
3891 is found, will then attempt to open it as a corefile.
3893 * Changes in ARM configurations.
3895 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3896 configuration is fully multi-arch.
3898 * New native configurations
3900 ARM NetBSD arm*-*-netbsd*
3901 x86 OpenBSD i[3456]86-*-openbsd*
3902 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3903 Sparc64 running FreeBSD sparc64-*-freebsd*
3907 Sanyo XStormy16 xstormy16-elf
3909 * OBSOLETE configurations and files
3911 Configurations that have been declared obsolete in this release have
3912 been commented out. Unless there is activity to revive these
3913 configurations, the next release of GDB will have their sources
3914 permanently REMOVED.
3916 AMD 29k family via UDI a29k-amd-udi, udi29k
3917 A29K VxWorks a29k-*-vxworks
3918 AMD 29000 embedded, using EBMON a29k-none-none
3919 AMD 29000 embedded with COFF a29k-none-coff
3920 AMD 29000 embedded with a.out a29k-none-aout
3922 testsuite/gdb.hp/gdb.threads-hp/ directory
3924 * REMOVED configurations and files
3926 TI TMS320C80 tic80-*-*
3928 PowerPC Solaris powerpcle-*-solaris*
3929 PowerPC Windows NT powerpcle-*-cygwin32
3930 PowerPC Netware powerpc-*-netware*
3931 Harris/CXUX m88k m88*-harris-cxux*
3932 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3933 ns32k-utek-sysv* ns32k-utek-*
3934 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3935 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3936 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3937 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3938 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3940 * Changes to command line processing
3942 The new `--args' feature can be used to specify command-line arguments
3943 for the inferior from gdb's command line.
3945 * Changes to key bindings
3947 There is a new `operate-and-get-next' function bound to `C-o'.
3949 *** Changes in GDB 5.1.1
3951 Fix compile problem on DJGPP.
3953 Fix a problem with floating-point registers on the i386 being
3956 Fix to stop GDB crashing on .debug_str debug info.
3958 Numerous documentation fixes.
3960 Numerous testsuite fixes.
3962 *** Changes in GDB 5.1:
3964 * New native configurations
3966 Alpha FreeBSD alpha*-*-freebsd*
3967 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3968 MIPS GNU/Linux mips*-*-linux*
3969 MIPS SGI Irix 6.x mips*-sgi-irix6*
3970 ia64 AIX ia64-*-aix*
3971 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3975 Motorola 68HC11 and 68HC12 m68hc11-elf
3977 UltraSparc running GNU/Linux sparc64-*-linux*
3979 * OBSOLETE configurations and files
3981 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3982 Harris/CXUX m88k m88*-harris-cxux*
3983 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3984 ns32k-utek-sysv* ns32k-utek-*
3985 TI TMS320C80 tic80-*-*
3987 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3988 PowerPC Solaris powerpcle-*-solaris*
3989 PowerPC Windows NT powerpcle-*-cygwin32
3990 PowerPC Netware powerpc-*-netware*
3991 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3992 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3993 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3994 Apple Macintosh (MPW) host N/A
3996 stuff.c (Program to stuff files into a specially prepared space in kdb)
3997 kdb-start.c (Main loop for the standalone kernel debugger)
3999 Configurations that have been declared obsolete in this release have
4000 been commented out. Unless there is activity to revive these
4001 configurations, the next release of GDB will have their sources
4002 permanently REMOVED.
4004 * REMOVED configurations and files
4006 Altos 3068 m68*-altos-*
4007 Convex c1-*-*, c2-*-*
4009 ARM RISCix arm-*-* (as host)
4013 * GDB has been converted to ISO C.
4015 GDB's source code has been converted to ISO C. In particular, the
4016 sources are fully protoized, and rely on standard headers being
4021 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4023 * The MI enabled by default.
4025 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4026 revised and enabled by default. Packages which use GDB as a debugging
4027 engine behind a UI or another front end are encouraged to switch to
4028 using the GDB/MI interface, instead of the old annotations interface
4029 which is now deprecated.
4031 * Support for debugging Pascal programs.
4033 GDB now includes support for debugging Pascal programs. The following
4034 main features are supported:
4036 - Pascal-specific data types such as sets;
4038 - automatic recognition of Pascal sources based on file-name
4041 - Pascal-style display of data types, variables, and functions;
4043 - a Pascal expression parser.
4045 However, some important features are not yet supported.
4047 - Pascal string operations are not supported at all;
4049 - there are some problems with boolean types;
4051 - Pascal type hexadecimal constants are not supported
4052 because they conflict with the internal variables format;
4054 - support for Pascal objects and classes is not full yet;
4056 - unlike Pascal, GDB is case-sensitive for symbol names.
4058 * Changes in completion.
4060 Commands such as `shell', `run' and `set args', which pass arguments
4061 to inferior programs, now complete on file names, similar to what
4062 users expect at the shell prompt.
4064 Commands which accept locations, such as `disassemble', `print',
4065 `breakpoint', `until', etc. now complete on filenames as well as
4066 program symbols. Thus, if you type "break foob TAB", and the source
4067 files linked into the programs include `foobar.c', that file name will
4068 be one of the candidates for completion. However, file names are not
4069 considered for completion after you typed a colon that delimits a file
4070 name from a name of a function in that file, as in "break foo.c:bar".
4072 `set demangle-style' completes on available demangling styles.
4074 * New platform-independent commands:
4076 It is now possible to define a post-hook for a command as well as a
4077 hook that runs before the command. For more details, see the
4078 documentation of `hookpost' in the GDB manual.
4080 * Changes in GNU/Linux native debugging.
4082 Support for debugging multi-threaded programs has been completely
4083 revised for all platforms except m68k and sparc. You can now debug as
4084 many threads as your system allows you to have.
4086 Attach/detach is supported for multi-threaded programs.
4088 Support for SSE registers was added for x86. This doesn't work for
4089 multi-threaded programs though.
4091 * Changes in MIPS configurations.
4093 Multi-arch support is enabled for all MIPS configurations.
4095 GDB can now be built as native debugger on SGI Irix 6.x systems for
4096 debugging n32 executables. (Debugging 64-bit executables is not yet
4099 * Unified support for hardware watchpoints in all x86 configurations.
4101 Most (if not all) native x86 configurations support hardware-assisted
4102 breakpoints and watchpoints in a unified manner. This support
4103 implements debug register sharing between watchpoints, which allows to
4104 put a virtually infinite number of watchpoints on the same address,
4105 and also supports watching regions up to 16 bytes with several debug
4108 The new maintenance command `maintenance show-debug-regs' toggles
4109 debugging print-outs in functions that insert, remove, and test
4110 watchpoints and hardware breakpoints.
4112 * Changes in the DJGPP native configuration.
4114 New command ``info dos sysinfo'' displays assorted information about
4115 the CPU, OS, memory, and DPMI server.
4117 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4118 display information about segment descriptors stored in GDT, LDT, and
4121 New commands ``info dos pde'' and ``info dos pte'' display entries
4122 from Page Directory and Page Tables (for now works with CWSDPMI only).
4123 New command ``info dos address-pte'' displays the Page Table entry for
4124 a given linear address.
4126 GDB can now pass command lines longer than 126 characters to the
4127 program being debugged (requires an update to the libdbg.a library
4128 which is part of the DJGPP development kit).
4130 DWARF2 debug info is now supported.
4132 It is now possible to `step' and `next' through calls to `longjmp'.
4134 * Changes in documentation.
4136 All GDB documentation was converted to GFDL, the GNU Free
4137 Documentation License.
4139 Tracepoints-related commands are now fully documented in the GDB
4142 TUI, the Text-mode User Interface, is now documented in the manual.
4144 Tracepoints-related commands are now fully documented in the GDB
4147 The "GDB Internals" manual now has an index. It also includes
4148 documentation of `ui_out' functions, GDB coding standards, x86
4149 hardware watchpoints, and memory region attributes.
4151 * GDB's version number moved to ``version.in''
4153 The Makefile variable VERSION has been replaced by the file
4154 ``version.in''. People creating GDB distributions should update the
4155 contents of this file.
4159 GUD support is now a standard part of the EMACS distribution.
4161 *** Changes in GDB 5.0:
4163 * Improved support for debugging FP programs on x86 targets
4165 Unified and much-improved support for debugging floating-point
4166 programs on all x86 targets. In particular, ``info float'' now
4167 displays the FP registers in the same format on all x86 targets, with
4168 greater level of detail.
4170 * Improvements and bugfixes in hardware-assisted watchpoints
4172 It is now possible to watch array elements, struct members, and
4173 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4174 on x86 targets no longer erroneously trigger when the address is
4177 * Improvements in the native DJGPP version of GDB
4179 The distribution now includes all the scripts and auxiliary files
4180 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4181 machines ``out of the box''.
4183 The DJGPP version can now debug programs that use signals. It is
4184 possible to catch signals that happened in the debuggee, deliver
4185 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4186 would kill the program being debugged.) Programs that hook hardware
4187 interrupts (keyboard, timer, etc.) can also be debugged.
4189 It is now possible to debug DJGPP programs that redirect their
4190 standard handles or switch them to raw (as opposed to cooked) mode, or
4191 even close them. The command ``run < foo > bar'' works as expected,
4192 and ``info terminal'' reports useful information about the debuggee's
4193 terminal, including raw/cooked mode, redirection, etc.
4195 The DJGPP version now uses termios functions for console I/O, which
4196 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4199 DOS-style file names with drive letters are now fully supported by
4202 It is now possible to debug DJGPP programs that switch their working
4203 directory. It is also possible to rerun the debuggee any number of
4204 times without restarting GDB; thus, you can use the same setup,
4205 breakpoints, etc. for many debugging sessions.
4207 * New native configurations
4209 ARM GNU/Linux arm*-*-linux*
4210 PowerPC GNU/Linux powerpc-*-linux*
4214 Motorola MCore mcore-*-*
4215 x86 VxWorks i[3456]86-*-vxworks*
4216 PowerPC VxWorks powerpc-*-vxworks*
4217 TI TMS320C80 tic80-*-*
4219 * OBSOLETE configurations
4221 Altos 3068 m68*-altos-*
4222 Convex c1-*-*, c2-*-*
4224 ARM RISCix arm-*-* (as host)
4227 Configurations that have been declared obsolete will be commented out,
4228 but the code will be left in place. If there is no activity to revive
4229 these configurations before the next release of GDB, the sources will
4230 be permanently REMOVED.
4232 * Gould support removed
4234 Support for the Gould PowerNode and NP1 has been removed.
4236 * New features for SVR4
4238 On SVR4 native platforms (such as Solaris), if you attach to a process
4239 without first loading a symbol file, GDB will now attempt to locate and
4240 load symbols from the running process's executable file.
4242 * Many C++ enhancements
4244 C++ support has been greatly improved. Overload resolution now works properly
4245 in almost all cases. RTTI support is on the way.
4247 * Remote targets can connect to a sub-program
4249 A popen(3) style serial-device has been added. This device starts a
4250 sub-process (such as a stand-alone simulator) and then communicates
4251 with that. The sub-program to run is specified using the syntax
4252 ``|<program> <args>'' vis:
4254 (gdb) set remotedebug 1
4255 (gdb) target extended-remote |mn10300-elf-sim program-args
4257 * MIPS 64 remote protocol
4259 A long standing bug in the mips64 remote protocol where by GDB
4260 expected certain 32 bit registers (ex SR) to be transfered as 32
4261 instead of 64 bits has been fixed.
4263 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4264 added to provide backward compatibility with older versions of GDB.
4266 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4268 The command ``set remotebinarydownload'' command has been replaced by
4269 ``set remote X-packet''. Other commands in ``set remote'' family
4270 include ``set remote P-packet''.
4272 * Breakpoint commands accept ranges.
4274 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4275 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4276 ``tracepoint passcount'' also accepts a range of tracepoints.
4278 * ``apropos'' command added.
4280 The ``apropos'' command searches through command names and
4281 documentation strings, printing out matches, making it much easier to
4282 try to find a command that does what you are looking for.
4286 A new machine oriented interface (MI) has been added to GDB. This
4287 interface is designed for debug environments running GDB as a separate
4288 process. This is part of the long term libGDB project. See the
4289 "GDB/MI" chapter of the GDB manual for further information. It can be
4290 enabled by configuring with:
4292 .../configure --enable-gdbmi
4294 *** Changes in GDB-4.18:
4296 * New native configurations
4298 HP-UX 10.20 hppa*-*-hpux10.20
4299 HP-UX 11.x hppa*-*-hpux11.0*
4300 M68K GNU/Linux m68*-*-linux*
4304 Fujitsu FR30 fr30-*-elf*
4305 Intel StrongARM strongarm-*-*
4306 Mitsubishi D30V d30v-*-*
4308 * OBSOLETE configurations
4310 Gould PowerNode, NP1 np1-*-*, pn-*-*
4312 Configurations that have been declared obsolete will be commented out,
4313 but the code will be left in place. If there is no activity to revive
4314 these configurations before the next release of GDB, the sources will
4315 be permanently REMOVED.
4319 As a compatibility experiment, GDB's source files buildsym.h and
4320 buildsym.c have been converted to pure standard C, no longer
4321 containing any K&R compatibility code. We believe that all systems in
4322 use today either come with a standard C compiler, or have a GCC port
4323 available. If this is not true, please report the affected
4324 configuration to bug-gdb@gnu.org immediately. See the README file for
4325 information about getting a standard C compiler if you don't have one
4330 GDB now uses readline 2.2.
4332 * set extension-language
4334 You can now control the mapping between filename extensions and source
4335 languages by using the `set extension-language' command. For instance,
4336 you can ask GDB to treat .c files as C++ by saying
4337 set extension-language .c c++
4338 The command `info extensions' lists all of the recognized extensions
4339 and their associated languages.
4341 * Setting processor type for PowerPC and RS/6000
4343 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4344 you can use the `set processor' command to specify what variant of the
4345 PowerPC family you are debugging. The command
4349 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4350 following PowerPC and RS6000 variants:
4352 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4353 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4355 403GC IBM PowerPC 403GC
4356 505 Motorola PowerPC 505
4357 860 Motorola PowerPC 860 or 850
4358 601 Motorola PowerPC 601
4359 602 Motorola PowerPC 602
4360 603 Motorola/IBM PowerPC 603 or 603e
4361 604 Motorola PowerPC 604 or 604e
4362 750 Motorola/IBM PowerPC 750 or 750
4364 At the moment, this command just tells GDB what to name the
4365 special-purpose processor registers. Since almost all the affected
4366 registers are inaccessible to user-level programs, this command is
4367 only useful for remote debugging in its present form.
4371 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4372 more extensive support for HP-UX. Added features include shared
4373 library support, kernel threads and hardware watchpoints for 11.00,
4374 support for HP's ANSI C and C++ compilers, and a compatibility mode
4375 for xdb and dbx commands.
4379 HP's donation includes the new concept of catchpoints, which is a
4380 generalization of the old catch command. On HP-UX, it is now possible
4381 to catch exec, fork, and vfork, as well as library loading.
4383 This means that the existing catch command has changed; its first
4384 argument now specifies the type of catch to be set up. See the
4385 output of "help catch" for a list of catchpoint types.
4387 * Debugging across forks
4389 On HP-UX, you can choose which process to debug when a fork() happens
4394 HP has donated a curses-based terminal user interface (TUI). To get
4395 it, build with --enable-tui. Although this can be enabled for any
4396 configuration, at present it only works for native HP debugging.
4398 * GDB remote protocol additions
4400 A new protocol packet 'X' that writes binary data is now available.
4401 Default behavior is to try 'X', then drop back to 'M' if the stub
4402 fails to respond. The settable variable `remotebinarydownload'
4403 allows explicit control over the use of 'X'.
4405 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4406 full 64-bit address. The command
4408 set remoteaddresssize 32
4410 can be used to revert to the old behaviour. For existing remote stubs
4411 the change should not be noticed, as the additional address information
4414 In order to assist in debugging stubs, you may use the maintenance
4415 command `packet' to send any text string to the stub. For instance,
4417 maint packet heythere
4419 sends the packet "$heythere#<checksum>". Note that it is very easy to
4420 disrupt a debugging session by sending the wrong packet at the wrong
4423 The compare-sections command allows you to compare section data on the
4424 target to what is in the executable file without uploading or
4425 downloading, by comparing CRC checksums.
4427 * Tracing can collect general expressions
4429 You may now collect general expressions at tracepoints. This requires
4430 further additions to the target-side stub; see tracepoint.c and
4431 doc/agentexpr.texi for further details.
4433 * mask-address variable for Mips
4435 For Mips targets, you may control the zeroing of the upper 32 bits of
4436 a 64-bit address by entering `set mask-address on'. This is mainly
4437 of interest to users of embedded R4xxx and R5xxx processors.
4439 * Higher serial baud rates
4441 GDB's serial code now allows you to specify baud rates 57600, 115200,
4442 230400, and 460800 baud. (Note that your host system may not be able
4443 to achieve all of these rates.)
4447 The i960 configuration now includes an initial implementation of a
4448 builtin simulator, contributed by Jim Wilson.
4451 *** Changes in GDB-4.17:
4453 * New native configurations
4455 Alpha GNU/Linux alpha*-*-linux*
4456 Unixware 2.x i[3456]86-unixware2*
4457 Irix 6.x mips*-sgi-irix6*
4458 PowerPC GNU/Linux powerpc-*-linux*
4459 PowerPC Solaris powerpcle-*-solaris*
4460 Sparc GNU/Linux sparc-*-linux*
4461 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4465 Argonaut Risc Chip (ARC) arc-*-*
4466 Hitachi H8/300S h8300*-*-*
4467 Matsushita MN10200 w/simulator mn10200-*-*
4468 Matsushita MN10300 w/simulator mn10300-*-*
4469 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4470 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4471 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4472 Mitsubishi D10V w/simulator d10v-*-*
4473 Mitsubishi M32R/D w/simulator m32r-*-elf*
4474 Tsqware Sparclet sparclet-*-*
4475 NEC V850 w/simulator v850-*-*
4477 * New debugging protocols
4479 ARM with RDI protocol arm*-*-*
4480 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4481 DDB and LSI variants of PMON protocol mips*-*-*
4482 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4483 PowerPC with SDS protocol powerpc{,le}-*-eabi
4484 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4488 All configurations can now understand and use the DWARF 2 debugging
4489 format. The choice is automatic, if the symbol file contains DWARF 2
4494 GDB now includes basic Java language support. This support is
4495 only useful with Java compilers that produce native machine code.
4497 * solib-absolute-prefix and solib-search-path
4499 For SunOS and SVR4 shared libraries, you may now set the prefix for
4500 loading absolute shared library symbol files, and the search path for
4501 locating non-absolute shared library symbol files.
4503 * Live range splitting
4505 GDB can now effectively debug code for which GCC has performed live
4506 range splitting as part of its optimization. See gdb/doc/LRS for
4507 more details on the expected format of the stabs information.
4511 GDB's support for the GNU Hurd, including thread debugging, has been
4512 updated to work with current versions of the Hurd.
4516 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4517 instruction set. ARM GDB automatically detects when Thumb
4518 instructions are in use, and adjusts disassembly and backtracing
4523 GDB's MIPS target configurations now handle the MIP16 16-bit
4528 GDB now includes support for overlays; if an executable has been
4529 linked such that multiple sections are based at the same address, GDB
4530 will decide which section to use for symbolic info. You can choose to
4531 control the decision manually, using overlay commands, or implement
4532 additional target-side support and use "overlay load-target" to bring
4533 in the overlay mapping. Do "help overlay" for more detail.
4537 The command "info symbol <address>" displays information about
4538 the symbol at the specified address.
4542 The standard remote protocol now includes an extension that allows
4543 asynchronous collection and display of trace data. This requires
4544 extensive support in the target-side debugging stub. Tracing mode
4545 includes a new interaction mode in GDB and new commands: see the
4546 file tracepoint.c for more details.
4550 Configurations for embedded MIPS now include a simulator contributed
4551 by Cygnus Solutions. The simulator supports the instruction sets
4552 of most MIPS variants.
4556 Sparc configurations may now include the ERC32 simulator contributed
4557 by the European Space Agency. The simulator is not built into
4558 Sparc targets by default; configure with --enable-sim to include it.
4562 For target configurations that may include multiple variants of a
4563 basic architecture (such as MIPS and SH), you may now set the
4564 architecture explicitly. "set arch" sets, "info arch" lists
4565 the possible architectures.
4567 *** Changes in GDB-4.16:
4569 * New native configurations
4571 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4572 M68K NetBSD m68k-*-netbsd*
4573 PowerPC AIX 4.x powerpc-*-aix*
4574 PowerPC MacOS powerpc-*-macos*
4575 PowerPC Windows NT powerpcle-*-cygwin32
4576 RS/6000 AIX 4.x rs6000-*-aix4*
4580 ARM with RDP protocol arm-*-*
4581 I960 with MON960 i960-*-coff
4582 MIPS VxWorks mips*-*-vxworks*
4583 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4584 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4586 Matra Sparclet sparclet-*-*
4590 The powerpc-eabi configuration now includes the PSIM simulator,
4591 contributed by Andrew Cagney, with assistance from Mike Meissner.
4592 PSIM is a very elaborate model of the PowerPC, including not only
4593 basic instruction set execution, but also details of execution unit
4594 performance and I/O hardware. See sim/ppc/README for more details.
4598 GDB now works with Solaris 2.5.
4600 * Windows 95/NT native
4602 GDB will now work as a native debugger on Windows 95 and Windows NT.
4603 To build it from source, you must use the "gnu-win32" environment,
4604 which uses a DLL to emulate enough of Unix to run the GNU tools.
4605 Further information, binaries, and sources are available at
4606 ftp.cygnus.com, under pub/gnu-win32.
4608 * dont-repeat command
4610 If a user-defined command includes the command `dont-repeat', then the
4611 command will not be repeated if the user just types return. This is
4612 useful if the command is time-consuming to run, so that accidental
4613 extra keystrokes don't run the same command many times.
4615 * Send break instead of ^C
4617 The standard remote protocol now includes an option to send a break
4618 rather than a ^C to the target in order to interrupt it. By default,
4619 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4621 * Remote protocol timeout
4623 The standard remote protocol includes a new variable `remotetimeout'
4624 that allows you to set the number of seconds before GDB gives up trying
4625 to read from the target. The default value is 2.
4627 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4629 By default GDB will automatically keep track of objects as they are
4630 loaded and unloaded by the dynamic linker. By using the command `set
4631 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4632 when shared library events occur, thus allowing you to set breakpoints
4633 in shared libraries which are explicitly loaded by the inferior.
4635 Note this feature does not work on hpux8. On hpux9 you must link
4636 /usr/lib/end.o into your program. This feature should work
4637 automatically on hpux10.
4639 * Irix 5.x hardware watchpoint support
4641 Irix 5 configurations now support the use of hardware watchpoints.
4643 * Mips protocol "SYN garbage limit"
4645 When debugging a Mips target using the `target mips' protocol, you
4646 may set the number of characters that GDB will ignore by setting
4647 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4648 every character. The default value is 1050.
4650 * Recording and replaying remote debug sessions
4652 If you set `remotelogfile' to the name of a file, gdb will write to it
4653 a recording of a remote debug session. This recording may then be
4654 replayed back to gdb using "gdbreplay". See gdbserver/README for
4655 details. This is useful when you have a problem with GDB while doing
4656 remote debugging; you can make a recording of the session and send it
4657 to someone else, who can then recreate the problem.
4659 * Speedups for remote debugging
4661 GDB includes speedups for downloading and stepping MIPS systems using
4662 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4663 and more efficient S-record downloading.
4665 * Memory use reductions and statistics collection
4667 GDB now uses less memory and reports statistics about memory usage.
4668 Try the `maint print statistics' command, for example.
4670 *** Changes in GDB-4.15:
4672 * Psymtabs for XCOFF
4674 The symbol reader for AIX GDB now uses partial symbol tables. This
4675 can greatly improve startup time, especially for large executables.
4677 * Remote targets use caching
4679 Remote targets now use a data cache to speed up communication with the
4680 remote side. The data cache could lead to incorrect results because
4681 it doesn't know about volatile variables, thus making it impossible to
4682 debug targets which use memory mapped I/O devices. `set remotecache
4683 off' turns the the data cache off.
4685 * Remote targets may have threads
4687 The standard remote protocol now includes support for multiple threads
4688 in the target system, using new protocol commands 'H' and 'T'. See
4689 gdb/remote.c for details.
4693 If GDB is configured with `--enable-netrom', then it will include
4694 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4695 acts as though it is a bank of ROM on the target board, but you can
4696 write into it over the network. GDB's support consists only of
4697 support for fast loading into the emulated ROM; to debug, you must use
4698 another protocol, such as standard remote protocol. The usual
4699 sequence is something like
4701 target nrom <netrom-hostname>
4703 target remote <netrom-hostname>:1235
4707 GDB now includes support for the Apple Macintosh, as a host only. It
4708 may be run as either an MPW tool or as a standalone application, and
4709 it can debug through the serial port. All the usual GDB commands are
4710 available, but to the target command, you must supply "serial" as the
4711 device type instead of "/dev/ttyXX". See mpw-README in the main
4712 directory for more information on how to build. The MPW configuration
4713 scripts */mpw-config.in support only a few targets, and only the
4714 mips-idt-ecoff target has been tested.
4718 GDB configuration now uses autoconf. This is not user-visible,
4719 but does simplify configuration and building.
4723 GDB now supports hpux10.
4725 *** Changes in GDB-4.14:
4727 * New native configurations
4729 x86 FreeBSD i[345]86-*-freebsd
4730 x86 NetBSD i[345]86-*-netbsd
4731 NS32k NetBSD ns32k-*-netbsd
4732 Sparc NetBSD sparc-*-netbsd
4736 A29K VxWorks a29k-*-vxworks
4737 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4738 CPU32 EST-300 emulator m68*-*-est*
4739 PowerPC ELF powerpc-*-elf
4742 * Alpha OSF/1 support for procfs
4744 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4745 possible to attach to running processes. As the mounting of the /proc
4746 filesystem is optional on the Alpha, GDB automatically determines
4747 the availability of /proc during startup. This can lead to problems
4748 if /proc is unmounted after GDB has been started.
4750 * Arguments to user-defined commands
4752 User commands may accept up to 10 arguments separated by whitespace.
4753 Arguments are accessed within the user command via $arg0..$arg9. A
4756 print $arg0 + $arg1 + $arg2
4758 To execute the command use:
4761 Defines the command "adder" which prints the sum of its three arguments.
4762 Note the arguments are text substitutions, so they may reference variables,
4763 use complex expressions, or even perform inferior function calls.
4765 * New `if' and `while' commands
4767 This makes it possible to write more sophisticated user-defined
4768 commands. Both commands take a single argument, which is the
4769 expression to evaluate, and must be followed by the commands to
4770 execute, one per line, if the expression is nonzero, the list being
4771 terminated by the word `end'. The `if' command list may include an
4772 `else' word, which causes the following commands to be executed only
4773 if the expression is zero.
4775 * Fortran source language mode
4777 GDB now includes partial support for Fortran 77. It will recognize
4778 Fortran programs and can evaluate a subset of Fortran expressions, but
4779 variables and functions may not be handled correctly. GDB will work
4780 with G77, but does not yet know much about symbols emitted by other
4783 * Better HPUX support
4785 Most debugging facilities now work on dynamic executables for HPPAs
4786 running hpux9 or later. You can attach to running dynamically linked
4787 processes, but by default the dynamic libraries will be read-only, so
4788 for instance you won't be able to put breakpoints in them. To change
4789 that behavior do the following before running the program:
4795 This will cause the libraries to be mapped private and read-write.
4796 To revert to the normal behavior, do this:
4802 You cannot set breakpoints or examine data in the library until after
4803 the library is loaded if the function/data symbols do not have
4806 GDB can now also read debug symbols produced by the HP C compiler on
4807 HPPAs (sorry, no C++, Fortran or 68k support).
4809 * Target byte order now dynamically selectable
4811 You can choose which byte order to use with a target system, via the
4812 commands "set endian big" and "set endian little", and you can see the
4813 current setting by using "show endian". You can also give the command
4814 "set endian auto", in which case GDB will use the byte order
4815 associated with the executable. Currently, only embedded MIPS
4816 configurations support dynamic selection of target byte order.
4818 * New DOS host serial code
4820 This version uses DPMI interrupts to handle buffered I/O, so you
4821 no longer need to run asynctsr when debugging boards connected to
4824 *** Changes in GDB-4.13:
4826 * New "complete" command
4828 This lists all the possible completions for the rest of the line, if it
4829 were to be given as a command itself. This is intended for use by emacs.
4831 * Trailing space optional in prompt
4833 "set prompt" no longer adds a space for you after the prompt you set. This
4834 allows you to set a prompt which ends in a space or one that does not.
4836 * Breakpoint hit counts
4838 "info break" now displays a count of the number of times the breakpoint
4839 has been hit. This is especially useful in conjunction with "ignore"; you
4840 can ignore a large number of breakpoint hits, look at the breakpoint info
4841 to see how many times the breakpoint was hit, then run again, ignoring one
4842 less than that number, and this will get you quickly to the last hit of
4845 * Ability to stop printing at NULL character
4847 "set print null-stop" will cause GDB to stop printing the characters of
4848 an array when the first NULL is encountered. This is useful when large
4849 arrays actually contain only short strings.
4851 * Shared library breakpoints
4853 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4854 breakpoints in shared libraries before the executable is run.
4856 * Hardware watchpoints
4858 There is a new hardware breakpoint for the watch command for sparclite
4859 targets. See gdb/sparclite/hw_breakpoint.note.
4861 Hardware watchpoints are also now supported under GNU/Linux.
4865 Annotations have been added. These are for use with graphical interfaces,
4866 and are still experimental. Currently only gdba.el uses these.
4868 * Improved Irix 5 support
4870 GDB now works properly with Irix 5.2.
4872 * Improved HPPA support
4874 GDB now works properly with the latest GCC and GAS.
4876 * New native configurations
4878 Sequent PTX4 i[34]86-sequent-ptx4
4879 HPPA running OSF/1 hppa*-*-osf*
4880 Atari TT running SVR4 m68*-*-sysv4*
4881 RS/6000 LynxOS rs6000-*-lynxos*
4885 OS/9000 i[34]86-*-os9k
4886 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4889 * Hitachi SH7000 and E7000-PC ICE support
4891 There is now support for communicating with the Hitachi E7000-PC ICE.
4892 This is available automatically when GDB is configured for the SH.
4896 As usual, a variety of small fixes and improvements, both generic
4897 and configuration-specific. See the ChangeLog for more detail.
4899 *** Changes in GDB-4.12:
4901 * Irix 5 is now supported
4905 GDB-4.12 on the HPPA has a number of changes which make it unable
4906 to debug the output from the currently released versions of GCC and
4907 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4908 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4909 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4912 *** Changes in GDB-4.11:
4914 * User visible changes:
4918 The "set remotedebug" option is now consistent between the mips remote
4919 target, remote targets using the gdb-specific protocol, UDI (AMD's
4920 debug protocol for the 29k) and the 88k bug monitor. It is now an
4921 integer specifying a debug level (normally 0 or 1, but 2 means more
4922 debugging info for the mips target).
4924 * DEC Alpha native support
4926 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4927 debug info, but GDB works fairly well with the DEC compiler and should
4928 work with a future GCC release. See the README file for a few
4929 Alpha-specific notes.
4931 * Preliminary thread implementation
4933 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4935 * LynxOS native and target support for 386
4937 This release has been hosted on LynxOS 2.2, and also can be configured
4938 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4941 * Improvements in C++ mangling/demangling.
4943 This release has much better g++ debugging, specifically in name
4944 mangling/demangling, virtual function calls, print virtual table,
4945 call methods, ...etc.
4947 *** Changes in GDB-4.10:
4949 * User visible changes:
4951 Remote debugging using the GDB-specific (`target remote') protocol now
4952 supports the `load' command. This is only useful if you have some
4953 other way of getting the stub to the target system, and you can put it
4954 somewhere in memory where it won't get clobbered by the download.
4956 Filename completion now works.
4958 When run under emacs mode, the "info line" command now causes the
4959 arrow to point to the line specified. Also, "info line" prints
4960 addresses in symbolic form (as well as hex).
4962 All vxworks based targets now support a user settable option, called
4963 vxworks-timeout. This option represents the number of seconds gdb
4964 should wait for responses to rpc's. You might want to use this if
4965 your vxworks target is, perhaps, a slow software simulator or happens
4966 to be on the far side of a thin network line.
4970 This release contains support for using a DEC alpha as a GDB host for
4971 cross debugging. Native alpha debugging is not supported yet.
4974 *** Changes in GDB-4.9:
4978 This is the first GDB release which is accompanied by a matching testsuite.
4979 The testsuite requires installation of dejagnu, which should be available
4980 via ftp from most sites that carry GNU software.
4984 'Cfront' style demangling has had its name changed to 'ARM' style, to
4985 emphasize that it was written from the specifications in the C++ Annotated
4986 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4987 disclaimers, it still generated too much confusion with users attempting to
4988 use gdb with AT&T cfront.
4992 GDB now uses a standard remote interface to a simulator library.
4993 So far, the library contains simulators for the Zilog Z8001/2, the
4994 Hitachi H8/300, H8/500 and Super-H.
4996 * New targets supported
4998 H8/300 simulator h8300-hitachi-hms or h8300hms
4999 H8/500 simulator h8500-hitachi-hms or h8500hms
5000 SH simulator sh-hitachi-hms or sh
5001 Z8000 simulator z8k-zilog-none or z8ksim
5002 IDT MIPS board over serial line mips-idt-ecoff
5004 Cross-debugging to GO32 targets is supported. It requires a custom
5005 version of the i386-stub.c module which is integrated with the
5006 GO32 memory extender.
5008 * New remote protocols
5010 MIPS remote debugging protocol.
5012 * New source languages supported
5014 This version includes preliminary support for Chill, a Pascal like language
5015 used by telecommunications companies. Chill support is also being integrated
5016 into the GNU compiler, but we don't know when it will be publically available.
5019 *** Changes in GDB-4.8:
5021 * HP Precision Architecture supported
5023 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5024 version of this support was available as a set of patches from the
5025 University of Utah. GDB does not support debugging of programs
5026 compiled with the HP compiler, because HP will not document their file
5027 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5028 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5030 Many problems in the preliminary version have been fixed.
5032 * Faster and better demangling
5034 We have improved template demangling and fixed numerous bugs in the GNU style
5035 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5036 character types (wchar_t) are now supported. Demangling of each symbol is now
5037 only done once, and is cached when the symbol table for a file is read in.
5038 This results in a small increase in memory usage for C programs, a moderate
5039 increase in memory usage for C++ programs, and a fantastic speedup in
5042 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5043 from the specifications in the Annotated Reference Manual, which AT&T's
5044 compiler does not actually implement.
5046 * G++ multiple inheritance compiler problem
5048 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5049 inheritance lattices was reworked to properly discover ambiguities. We
5050 recently found an example which causes this new algorithm to fail in a
5051 very subtle way, producing bad debug information for those classes.
5052 The file 'gcc.patch' (in this directory) can be applied to gcc to
5053 circumvent the problem. A future GCC release will contain a complete
5056 The previous G++ debug info problem (mentioned below for the gdb-4.7
5057 release) is fixed in gcc version 2.3.2.
5059 * Improved configure script
5061 The `configure' script will now attempt to guess your system type if
5062 you don't supply a host system type. The old scheme of supplying a
5063 host system triplet is preferable over using this. All the magic is
5064 done in the new `config.guess' script. Examine it for details.
5066 We have also brought our configure script much more in line with the FSF's
5067 version. It now supports the --with-xxx options. In particular,
5068 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5069 The resulting GDB will not be able to read arbitrary object file formats --
5070 only the format ``expected'' to be used on the configured target system.
5071 We hope to make this the default in a future release.
5073 * Documentation improvements
5075 There's new internal documentation on how to modify GDB, and how to
5076 produce clean changes to the code. We implore people to read it
5077 before submitting changes.
5079 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5080 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5081 `info' files are also provided. To build `info' files from scratch,
5082 you will need the latest `makeinfo' release, which will be available in
5083 a future texinfo-X.Y release.
5085 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5086 We're not sure exactly which versions have this problem, but it has
5087 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5088 or better. If that isn't possible, there is a patch in
5089 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5090 around this problem.
5094 GDB now supports array constants that can be used in expressions typed in by
5095 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5096 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5099 The new directory `gdb/sparclite' contains a program that demonstrates
5100 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5102 * New native hosts supported
5104 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5105 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5107 * New targets supported
5109 AMD 29k family via UDI a29k-amd-udi or udi29k
5111 * New file formats supported
5113 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5114 HPUX core files, and SCO 3.2v2 core files.
5118 Attaching to processes now works again; thanks for the many bug reports.
5120 We have also stomped on a bunch of core dumps caused by
5121 printf_filtered("%s") problems.
5123 We eliminated a copyright problem on the rpc and ptrace header files
5124 for VxWorks, which was discovered at the last minute during the 4.7
5125 release. You should now be able to build a VxWorks GDB.
5127 You can now interrupt gdb while an attached process is running. This
5128 will cause the attached process to stop, and give control back to GDB.
5130 We fixed problems caused by using too many file descriptors
5131 for reading symbols from object files and libraries. This was
5132 especially a problem for programs that used many (~100) shared
5135 The `step' command now only enters a subroutine if there is line number
5136 information for the subroutine. Otherwise it acts like the `next'
5137 command. Previously, `step' would enter subroutines if there was
5138 any debugging information about the routine. This avoids problems
5139 when using `cc -g1' on MIPS machines.
5141 * Internal improvements
5143 GDB's internal interfaces have been improved to make it easier to support
5144 debugging of multiple languages in the future.
5146 GDB now uses a common structure for symbol information internally.
5147 Minimal symbols (derived from linkage symbols in object files), partial
5148 symbols (from a quick scan of debug information), and full symbols
5149 contain a common subset of information, making it easier to write
5150 shared code that handles any of them.
5152 * New command line options
5154 We now accept --silent as an alias for --quiet.
5158 The memory-mapped-malloc library is now licensed under the GNU Library
5159 General Public License.
5161 *** Changes in GDB-4.7:
5163 * Host/native/target split
5165 GDB has had some major internal surgery to untangle the support for
5166 hosts and remote targets. Now, when you configure GDB for a remote
5167 target, it will no longer load in all of the support for debugging
5168 local programs on the host. When fully completed and tested, this will
5169 ensure that arbitrary host/target combinations are possible.
5171 The primary conceptual shift is to separate the non-portable code in
5172 GDB into three categories. Host specific code is required any time GDB
5173 is compiled on that host, regardless of the target. Target specific
5174 code relates to the peculiarities of the target, but can be compiled on
5175 any host. Native specific code is everything else: it can only be
5176 built when the host and target are the same system. Child process
5177 handling and core file support are two common `native' examples.
5179 GDB's use of /proc for controlling Unix child processes is now cleaner.
5180 It has been split out into a single module under the `target_ops' vector,
5181 plus two native-dependent functions for each system that uses /proc.
5183 * New hosts supported
5185 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5186 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5187 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5189 * New targets supported
5191 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5192 68030 and CPU32 m68030-*-*, m68332-*-*
5194 * New native hosts supported
5196 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5197 (386bsd is not well tested yet)
5198 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5200 * New file formats supported
5202 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5203 supports reading of `a.out.adobe' object files, which are an a.out
5204 format extended with minimal information about multiple sections.
5208 `show copying' is the same as the old `info copying'.
5209 `show warranty' is the same as `info warrantee'.
5210 These were renamed for consistency. The old commands continue to work.
5212 `info handle' is a new alias for `info signals'.
5214 You can now define pre-command hooks, which attach arbitrary command
5215 scripts to any command. The commands in the hook will be executed
5216 prior to the user's command. You can also create a hook which will be
5217 executed whenever the program stops. See gdb.texinfo.
5221 We now deal with Cfront style name mangling, and can even extract type
5222 info from mangled symbols. GDB can automatically figure out which
5223 symbol mangling style your C++ compiler uses.
5225 Calling of methods and virtual functions has been improved as well.
5229 The crash that occured when debugging Sun Ansi-C compiled binaries is
5230 fixed. This was due to mishandling of the extra N_SO stabs output
5233 We also finally got Ultrix 4.2 running in house, and fixed core file
5234 support, with help from a dozen people on the net.
5236 John M. Farrell discovered that the reason that single-stepping was so
5237 slow on all of the Mips based platforms (primarily SGI and DEC) was
5238 that we were trying to demangle and lookup a symbol used for internal
5239 purposes on every instruction that was being stepped through. Changing
5240 the name of that symbol so that it couldn't be mistaken for a C++
5241 mangled symbol sped things up a great deal.
5243 Rich Pixley sped up symbol lookups in general by getting much smarter
5244 about when C++ symbol mangling is necessary. This should make symbol
5245 completion (TAB on the command line) much faster. It's not as fast as
5246 we'd like, but it's significantly faster than gdb-4.6.
5250 A new user controllable variable 'call_scratch_address' can
5251 specify the location of a scratch area to be used when GDB
5252 calls a function in the target. This is necessary because the
5253 usual method of putting the scratch area on the stack does not work
5254 in systems that have separate instruction and data spaces.
5256 We integrated changes to support the 29k UDI (Universal Debugger
5257 Interface), but discovered at the last minute that we didn't have all
5258 of the appropriate copyright paperwork. We are working with AMD to
5259 resolve this, and hope to have it available soon.
5263 We have sped up the remote serial line protocol, especially for targets
5264 with lots of registers. It now supports a new `expedited status' ('T')
5265 message which can be used in place of the existing 'S' status message.
5266 This allows the remote stub to send only the registers that GDB
5267 needs to make a quick decision about single-stepping or conditional
5268 breakpoints, eliminating the need to fetch the entire register set for
5269 each instruction being stepped through.
5271 The GDB remote serial protocol now implements a write-through cache for
5272 registers, only re-reading the registers if the target has run.
5274 There is also a new remote serial stub for SPARC processors. You can
5275 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5276 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5277 processor with a serial port.
5281 Configure.in files have become much easier to read and modify. A new
5282 `table driven' format makes it more obvious what configurations are
5283 supported, and what files each one uses.
5287 There is a new opcodes library which will eventually contain all of the
5288 disassembly routines and opcode tables. At present, it only contains
5289 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5290 disassembler (binutils/objdump) to share these routines.
5292 The libiberty library is now copylefted under the GNU Library General
5293 Public License. This allows more liberal use, and was done so libg++
5294 can use it. This makes no difference to GDB, since the Library License
5295 grants all the rights from the General Public License.
5299 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5300 reference to the stabs symbol info used by the debugger. It is (as far
5301 as we know) the only published document on this fascinating topic. We
5302 encourage you to read it, compare it to the stabs information on your
5303 system, and send improvements on the document in general (to
5304 bug-gdb@prep.ai.mit.edu).
5306 And, of course, many bugs have been fixed.
5309 *** Changes in GDB-4.6:
5311 * Better support for C++ function names
5313 GDB now accepts as input the "demangled form" of C++ overloaded function
5314 names and member function names, and can do command completion on such names
5315 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5316 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5317 Make use of command completion, it is your friend.
5319 GDB also now accepts a variety of C++ mangled symbol formats. They are
5320 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5321 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5322 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5323 for the list of formats.
5325 * G++ symbol mangling problem
5327 Recent versions of gcc have a bug in how they emit debugging information for
5328 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5329 directory) can be applied to gcc to fix the problem. Alternatively, if you
5330 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5331 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5332 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5335 * New 'maintenance' command
5337 All of the commands related to hacking GDB internals have been moved out of
5338 the main command set, and now live behind the 'maintenance' command. This
5339 can also be abbreviated as 'mt'. The following changes were made:
5341 dump-me -> maintenance dump-me
5342 info all-breakpoints -> maintenance info breakpoints
5343 printmsyms -> maintenance print msyms
5344 printobjfiles -> maintenance print objfiles
5345 printpsyms -> maintenance print psymbols
5346 printsyms -> maintenance print symbols
5348 The following commands are new:
5350 maintenance demangle Call internal GDB demangler routine to
5351 demangle a C++ link name and prints the result.
5352 maintenance print type Print a type chain for a given symbol
5354 * Change to .gdbinit file processing
5356 We now read the $HOME/.gdbinit file before processing the argv arguments
5357 (e.g. reading symbol files or core files). This allows global parameters to
5358 be set, which will apply during the symbol reading. The ./.gdbinit is still
5359 read after argv processing.
5361 * New hosts supported
5363 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5365 GNU/Linux support i386-unknown-linux or linux
5367 We are also including code to support the HP/PA running BSD and HPUX. This
5368 is almost guaranteed not to work, as we didn't have time to test or build it
5369 for this release. We are including it so that the more adventurous (or
5370 masochistic) of you can play with it. We also had major problems with the
5371 fact that the compiler that we got from HP doesn't support the -g option.
5374 * New targets supported
5376 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5378 * More smarts about finding #include files
5380 GDB now remembers the compilation directory for all include files, and for
5381 all files from which C is generated (like yacc and lex sources). This
5382 greatly improves GDB's ability to find yacc/lex sources, and include files,
5383 especially if you are debugging your program from a directory different from
5384 the one that contains your sources.
5386 We also fixed a bug which caused difficulty with listing and setting
5387 breakpoints in include files which contain C code. (In the past, you had to
5388 try twice in order to list an include file that you hadn't looked at before.)
5390 * Interesting infernals change
5392 GDB now deals with arbitrary numbers of sections, where the symbols for each
5393 section must be relocated relative to that section's landing place in the
5394 target's address space. This work was needed to support ELF with embedded
5395 stabs used by Solaris-2.0.
5397 * Bug fixes (of course!)
5399 There have been loads of fixes for the following things:
5400 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5401 i960, stabs, DOS(GO32), procfs, etc...
5403 See the ChangeLog for details.
5405 *** Changes in GDB-4.5:
5407 * New machines supported (host and target)
5409 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5411 SGI Irix-4.x mips-sgi-irix4 or iris4
5413 * New malloc package
5415 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5416 Mmalloc is capable of handling mutiple heaps of memory. It is also
5417 capable of saving a heap to a file, and then mapping it back in later.
5418 This can be used to greatly speedup the startup of GDB by using a
5419 pre-parsed symbol table which lives in a mmalloc managed heap. For
5420 more details, please read mmalloc/mmalloc.texi.
5424 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5425 'help info proc' for details.
5427 * MIPS ecoff symbol table format
5429 The code that reads MIPS symbol table format is now supported on all hosts.
5430 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5433 * File name changes for MS-DOS
5435 Many files in the config directories have been renamed to make it easier to
5436 support GDB on MS-DOSe systems (which have very restrictive file name
5437 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5438 environment) is close to working but has some remaining problems. Note
5439 that debugging of DOS programs is not supported, due to limitations
5440 in the ``operating system'', but it can be used to host cross-debugging.
5442 * Cross byte order fixes
5444 Many fixes have been made to support cross debugging of Sparc and MIPS
5445 targets from hosts whose byte order differs.
5447 * New -mapped and -readnow options
5449 If memory-mapped files are available on your system through the 'mmap'
5450 system call, you can use the -mapped option on the `file' or
5451 `symbol-file' commands to cause GDB to write the symbols from your
5452 program into a reusable file. If the program you are debugging is
5453 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5454 Future GDB debugging sessions will notice the presence of this file,
5455 and will quickly map in symbol information from it, rather than reading
5456 the symbol table from the executable program. Using the '-mapped'
5457 option in a GDB `file' or `symbol-file' command has the same effect as
5458 starting GDB with the '-mapped' command-line option.
5460 You can cause GDB to read the entire symbol table immediately by using
5461 the '-readnow' option with any of the commands that load symbol table
5462 information (or on the GDB command line). This makes the command
5463 slower, but makes future operations faster.
5465 The -mapped and -readnow options are typically combined in order to
5466 build a `fred.syms' file that contains complete symbol information.
5467 A simple GDB invocation to do nothing but build a `.syms' file for future
5470 gdb -batch -nx -mapped -readnow programname
5472 The `.syms' file is specific to the host machine on which GDB is run.
5473 It holds an exact image of GDB's internal symbol table. It cannot be
5474 shared across multiple host platforms.
5476 * longjmp() handling
5478 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5479 siglongjmp() without losing control. This feature has not yet been ported to
5480 all systems. It currently works on many 386 platforms, all MIPS-based
5481 platforms (SGI, DECstation, etc), and Sun3/4.
5485 Preliminary work has been put in to support the new Solaris OS from Sun. At
5486 this time, it can control and debug processes, but it is not capable of
5491 As always, many many bug fixes. The major areas were with g++, and mipsread.
5492 People using the MIPS-based platforms should experience fewer mysterious
5493 crashes and trashed symbol tables.
5495 *** Changes in GDB-4.4:
5497 * New machines supported (host and target)
5499 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5501 BSD Reno on Vax vax-dec-bsd
5502 Ultrix on Vax vax-dec-ultrix
5504 * New machines supported (target)
5506 AMD 29000 embedded, using EBMON a29k-none-none
5510 GDB continues to improve its handling of C++. `References' work better.
5511 The demangler has also been improved, and now deals with symbols mangled as
5512 per the Annotated C++ Reference Guide.
5514 GDB also now handles `stabs' symbol information embedded in MIPS
5515 `ecoff' symbol tables. Since the ecoff format was not easily
5516 extensible to handle new languages such as C++, this appeared to be a
5517 good way to put C++ debugging info into MIPS binaries. This option
5518 will be supported in the GNU C compiler, version 2, when it is
5521 * New features for SVR4
5523 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5524 shared libraries. Debugging dynamically linked programs should present
5525 only minor differences from debugging statically linked programs.
5527 The `info proc' command will print out information about any process
5528 on an SVR4 system (including the one you are debugging). At the moment,
5529 it prints the address mappings of the process.
5531 If you bring up GDB on another SVR4 system, please send mail to
5532 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5534 * Better dynamic linking support in SunOS
5536 Reading symbols from shared libraries which contain debugging symbols
5537 now works properly. However, there remain issues such as automatic
5538 skipping of `transfer vector' code during function calls, which
5539 make it harder to debug code in a shared library, than to debug the
5540 same code linked statically.
5544 GDB is now using the latest `getopt' routines from the FSF. This
5545 version accepts the -- prefix for options with long names. GDB will
5546 continue to accept the old forms (-option and +option) as well.
5547 Various single letter abbreviations for options have been explicity
5548 added to the option table so that they won't get overshadowed in the
5549 future by other options that begin with the same letter.
5553 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5554 Many assorted bugs have been handled. Many more remain to be handled.
5555 See the various ChangeLog files (primarily in gdb and bfd) for details.
5558 *** Changes in GDB-4.3:
5560 * New machines supported (host and target)
5562 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5563 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5564 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5566 * Almost SCO Unix support
5568 We had hoped to support:
5569 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5570 (except for core file support), but we discovered very late in the release
5571 that it has problems with process groups that render gdb unusable. Sorry
5572 about that. I encourage people to fix it and post the fixes.
5574 * Preliminary ELF and DWARF support
5576 GDB can read ELF object files on System V Release 4, and can handle
5577 debugging records for C, in DWARF format, in ELF files. This support
5578 is preliminary. If you bring up GDB on another SVR4 system, please
5579 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5584 GDB now uses the latest `readline' library. One user-visible change
5585 is that two tabs will list possible command completions, which previously
5586 required typing M-? (meta-question mark, or ESC ?).
5590 The `stepi' bug that many of you noticed has been squashed.
5591 Many bugs in C++ have been handled. Many more remain to be handled.
5592 See the various ChangeLog files (primarily in gdb and bfd) for details.
5594 * State of the MIPS world (in case you wondered):
5596 GDB can understand the symbol tables emitted by the compilers
5597 supplied by most vendors of MIPS-based machines, including DEC. These
5598 symbol tables are in a format that essentially nobody else uses.
5600 Some versions of gcc come with an assembler post-processor called
5601 mips-tfile. This program is required if you want to do source-level
5602 debugging of gcc-compiled programs. I believe FSF does not ship
5603 mips-tfile with gcc version 1, but it will eventually come with gcc
5606 Debugging of g++ output remains a problem. g++ version 1.xx does not
5607 really support it at all. (If you're lucky, you should be able to get
5608 line numbers and stack traces to work, but no parameters or local
5609 variables.) With some work it should be possible to improve the
5612 When gcc version 2 is released, you will have somewhat better luck.
5613 However, even then you will get confusing results for inheritance and
5616 We will eventually provide full debugging of g++ output on
5617 DECstations. This will probably involve some kind of stabs-in-ecoff
5618 encapulation, but the details have not been worked out yet.
5621 *** Changes in GDB-4.2:
5623 * Improved configuration
5625 Only one copy of `configure' exists now, and it is not self-modifying.
5626 Porting BFD is simpler.
5630 The `step' and `next' commands now only stop at the first instruction
5631 of a source line. This prevents the multiple stops that used to occur
5632 in switch statements, for-loops, etc. `Step' continues to stop if a
5633 function that has debugging information is called within the line.
5637 Lots of small bugs fixed. More remain.
5639 * New host supported (not target)
5641 Intel 386 PC clone running Mach i386-none-mach
5644 *** Changes in GDB-4.1:
5646 * Multiple source language support
5648 GDB now has internal scaffolding to handle several source languages.
5649 It determines the type of each source file from its filename extension,
5650 and will switch expression parsing and number formatting to match the
5651 language of the function in the currently selected stack frame.
5652 You can also specifically set the language to be used, with
5653 `set language c' or `set language modula-2'.
5657 GDB now has preliminary support for the GNU Modula-2 compiler,
5658 currently under development at the State University of New York at
5659 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5660 continue through the fall of 1991 and into 1992.
5662 Other Modula-2 compilers are currently not supported, and attempting to
5663 debug programs compiled with them will likely result in an error as the
5664 symbol table is read. Feel free to work on it, though!
5666 There are hooks in GDB for strict type checking and range checking,
5667 in the `Modula-2 philosophy', but they do not currently work.
5671 GDB can now write to executable and core files (e.g. patch
5672 a variable's value). You must turn this switch on, specify
5673 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5674 by assigning a new value to a variable. Modifications take
5677 * Automatic SunOS shared library reading
5679 When you run your program, GDB automatically determines where its
5680 shared libraries (if any) have been loaded, and reads their symbols.
5681 The `share' command is no longer needed. This also works when
5682 examining core files.
5686 You can specify the number of lines that the `list' command shows.
5689 * New machines supported (host and target)
5691 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5692 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5693 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5695 * New hosts supported (not targets)
5697 IBM RT/PC: romp-ibm-aix or rtpc
5699 * New targets supported (not hosts)
5701 AMD 29000 embedded with COFF a29k-none-coff
5702 AMD 29000 embedded with a.out a29k-none-aout
5703 Ultracomputer remote kernel debug a29k-nyu-kern
5705 * New remote interfaces
5711 *** Changes in GDB-4.0:
5715 Wide output is wrapped at good places to make the output more readable.
5717 Gdb now supports cross-debugging from a host machine of one type to a
5718 target machine of another type. Communication with the target system
5719 is over serial lines. The ``target'' command handles connecting to the
5720 remote system; the ``load'' command will download a program into the
5721 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5722 also supports debugging of realtime processes running under VxWorks,
5723 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5724 stub on the target system.
5726 New CPUs supported include the AMD 29000 and Intel 960.
5728 GDB now reads object files and symbol tables via a ``binary file''
5729 library, which allows a single copy of GDB to debug programs of multiple
5730 object file types such as a.out and coff.
5732 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5733 refcard.dvi and refcard.ps are available to format it).
5736 * Control-Variable user interface simplified
5738 All variables that control the operation of the debugger can be set
5739 by the ``set'' command, and displayed by the ``show'' command.
5741 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5742 ``Show prompt'' produces the response:
5743 Gdb's prompt is new-gdb=>.
5745 What follows are the NEW set commands. The command ``help set'' will
5746 print a complete list of old and new set commands. ``help set FOO''
5747 will give a longer description of the variable FOO. ``show'' will show
5748 all of the variable descriptions and their current settings.
5750 confirm on/off: Enables warning questions for operations that are
5751 hard to recover from, e.g. rerunning the program while
5752 it is already running. Default is ON.
5754 editing on/off: Enables EMACS style command line editing
5755 of input. Previous lines can be recalled with
5756 control-P, the current line can be edited with control-B,
5757 you can search for commands with control-R, etc.
5760 history filename NAME: NAME is where the gdb command history
5761 will be stored. The default is .gdb_history,
5762 or the value of the environment variable
5765 history size N: The size, in commands, of the command history. The
5766 default is 256, or the value of the environment variable
5769 history save on/off: If this value is set to ON, the history file will
5770 be saved after exiting gdb. If set to OFF, the
5771 file will not be saved. The default is OFF.
5773 history expansion on/off: If this value is set to ON, then csh-like
5774 history expansion will be performed on
5775 command line input. The default is OFF.
5777 radix N: Sets the default radix for input and output. It can be set
5778 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5779 in the current radix, so "set radix 10" is always a no-op.
5781 height N: This integer value is the number of lines on a page. Default
5782 is 24, the current `stty rows'' setting, or the ``li#''
5783 setting from the termcap entry matching the environment
5786 width N: This integer value is the number of characters on a line.
5787 Default is 80, the current `stty cols'' setting, or the ``co#''
5788 setting from the termcap entry matching the environment
5791 Note: ``set screensize'' is obsolete. Use ``set height'' and
5792 ``set width'' instead.
5794 print address on/off: Print memory addresses in various command displays,
5795 such as stack traces and structure values. Gdb looks
5796 more ``symbolic'' if you turn this off; it looks more
5797 ``machine level'' with it on. Default is ON.
5799 print array on/off: Prettyprint arrays. New convenient format! Default
5802 print demangle on/off: Print C++ symbols in "source" form if on,
5805 print asm-demangle on/off: Same, for assembler level printouts
5808 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5811 * Support for Epoch Environment.
5813 The epoch environment is a version of Emacs v18 with windowing. One
5814 new command, ``inspect'', is identical to ``print'', except that if you
5815 are running in the epoch environment, the value is printed in its own
5819 * Support for Shared Libraries
5821 GDB can now debug programs and core files that use SunOS shared libraries.
5822 Symbols from a shared library cannot be referenced
5823 before the shared library has been linked with the program (this
5824 happens after you type ``run'' and before the function main() is entered).
5825 At any time after this linking (including when examining core files
5826 from dynamically linked programs), gdb reads the symbols from each
5827 shared library when you type the ``sharedlibrary'' command.
5828 It can be abbreviated ``share''.
5830 sharedlibrary REGEXP: Load shared object library symbols for files
5831 matching a unix regular expression. No argument
5832 indicates to load symbols for all shared libraries.
5834 info sharedlibrary: Status of loaded shared libraries.
5839 A watchpoint stops execution of a program whenever the value of an
5840 expression changes. Checking for this slows down execution
5841 tremendously whenever you are in the scope of the expression, but is
5842 quite useful for catching tough ``bit-spreader'' or pointer misuse
5843 problems. Some machines such as the 386 have hardware for doing this
5844 more quickly, and future versions of gdb will use this hardware.
5846 watch EXP: Set a watchpoint (breakpoint) for an expression.
5848 info watchpoints: Information about your watchpoints.
5850 delete N: Deletes watchpoint number N (same as breakpoints).
5851 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5852 enable N: Re-enables watchpoint number N (same as breakpoints).
5855 * C++ multiple inheritance
5857 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5860 * C++ exception handling
5862 Gdb now supports limited C++ exception handling. Besides the existing
5863 ability to breakpoint on an exception handler, gdb can breakpoint on
5864 the raising of an exception (before the stack is peeled back to the
5867 catch FOO: If there is a FOO exception handler in the dynamic scope,
5868 set a breakpoint to catch exceptions which may be raised there.
5869 Multiple exceptions (``catch foo bar baz'') may be caught.
5871 info catch: Lists all exceptions which may be caught in the
5872 current stack frame.
5875 * Minor command changes
5877 The command ``call func (arg, arg, ...)'' now acts like the print
5878 command, except it does not print or save a value if the function's result
5879 is void. This is similar to dbx usage.
5881 The ``up'' and ``down'' commands now always print the frame they end up
5882 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5883 frames without printing.
5885 * New directory command
5887 'dir' now adds directories to the FRONT of the source search path.
5888 The path starts off empty. Source files that contain debug information
5889 about the directory in which they were compiled can be found even
5890 with an empty path; Sun CC and GCC include this information. If GDB can't
5891 find your source file in the current directory, type "dir .".
5893 * Configuring GDB for compilation
5895 For normal use, type ``./configure host''. See README or gdb.texinfo
5898 GDB now handles cross debugging. If you are remotely debugging between
5899 two different machines, type ``./configure host -target=targ''.
5900 Host is the machine where GDB will run; targ is the machine
5901 where the program that you are debugging will run.