1 What has changed in GDB?
2 (Organized release by release)
6 New events which are triggered when GDB modifies the state of the
9 ** gdb.events.inferior_call_pre: Function call is about to be made.
10 ** gdb.events.inferior_call_post: Function call has just been made.
11 ** gdb.events.memory_changed: A memory location has been altered.
12 ** gdb.events.register_changed: A register has been altered.
14 *** Changes since GDB 7.8
16 * GDB now supports hardware watchpoints on x86 GNU Hurd.
20 ** You can now access frame registers from Python scripts.
21 ** New attribute 'producer' for gdb.Symtab objects.
22 ** gdb.Objfile objects have a new attribute "progspace",
23 which is the gdb.Progspace object of the containing program space.
24 ** gdb.Objfile objects have a new attribute "build_id",
25 which is the build ID generated when the file was built.
26 ** A new event "gdb.clear_objfiles" has been added, triggered when
27 selecting a new file to debug.
28 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
30 * New Python-based convenience functions:
32 ** $_caller_is(name [, number_of_frames])
33 ** $_caller_matches(regexp [, number_of_frames])
34 ** $_any_caller_is(name [, number_of_frames])
35 ** $_any_caller_matches(regexp [, number_of_frames])
39 queue-signal signal-name-or-number
40 Queue a signal to be delivered to the thread when it is resumed.
42 add-auto-load-scripts-directory directory
43 Add entries to the list of directories from which to load auto-loaded
46 * On resume, GDB now always passes the signal the program had stopped
47 for to the thread the signal was sent to, even if the user changed
48 threads before resuming. Previously GDB would often (but not
49 always) deliver the signal to the thread that happens to be current
52 * Conversely, the "signal" command now consistently delivers the
53 requested signal to the current thread. GDB now asks for
54 confirmation if the program had stopped for a signal and the user
55 switched threads meanwhile.
57 * "breakpoint always-inserted" modes "off" and "auto" merged.
59 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
60 won't remove breakpoints from the target until all threads stop,
61 even in non-stop mode. The "auto" mode has been removed, and "off"
62 is now the default mode.
66 ** The -list-thread-groups command outputs an exit-code field for
67 inferiors that have exited.
71 Support for these obsolete configurations has been removed.
73 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
74 SGI Irix-5.x mips-*-irix5*
75 SGI Irix-6.x mips-*-irix6*
76 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
77 VAX running Ultrix vax-*-ultrix*
79 *** Changes in GDB 7.8
81 * New command line options
84 This is an alias for the --data-directory option.
86 * GDB supports printing and modifying of variable length automatic arrays
87 as specified in ISO C99.
89 * The ARM simulator now supports instruction level tracing
90 with or without disassembly.
94 GDB now has support for scripting using Guile. Whether this is
95 available is determined at configure time.
96 Guile version 2.0 or greater is required.
97 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
99 * New commands (for set/show, see "New options" below)
103 Invoke CODE by passing it to the Guile interpreter.
107 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
109 info auto-load guile-scripts [regexp]
110 Print the list of automatically loaded Guile scripts.
112 * The source command is now capable of sourcing Guile scripts.
113 This feature is dependent on the debugger being built with Guile support.
117 set print symbol-loading (off|brief|full)
118 show print symbol-loading
119 Control whether to print informational messages when loading symbol
120 information for a file. The default is "full", but when debugging
121 programs with large numbers of shared libraries the amount of output
124 set guile print-stack (none|message|full)
125 show guile print-stack
126 Show a stack trace when an error is encountered in a Guile script.
128 set auto-load guile-scripts (on|off)
129 show auto-load guile-scripts
130 Control auto-loading of Guile script files.
132 maint ada set ignore-descriptive-types (on|off)
133 maint ada show ignore-descriptive-types
134 Control whether the debugger should ignore descriptive types in Ada
135 programs. The default is not to ignore the descriptive types. See
136 the user manual for more details on descriptive types and the intended
137 usage of this option.
139 set auto-connect-native-target
141 Control whether GDB is allowed to automatically connect to the
142 native target for the run, attach, etc. commands when not connected
143 to any target yet. See also "target native" below.
145 set record btrace replay-memory-access (read-only|read-write)
146 show record btrace replay-memory-access
147 Control what memory accesses are allowed during replay.
149 maint set target-async (on|off)
150 maint show target-async
151 This controls whether GDB targets operate in synchronous or
152 asynchronous mode. Normally the default is asynchronous, if it is
153 available; but this can be changed to more easily debug problems
154 occurring only in synchronous mode.
156 set mi-async (on|off)
158 Control whether MI asynchronous mode is preferred. This supersedes
159 "set target-async" of previous GDB versions.
161 * "set target-async" is deprecated as a CLI option and is now an alias
162 for "set mi-async" (only puts MI into async mode).
164 * Background execution commands (e.g., "c&", "s&", etc.) are now
165 possible ``out of the box'' if the target supports them. Previously
166 the user would need to explicitly enable the possibility with the
167 "set target-async on" command.
169 * New features in the GDB remote stub, GDBserver
171 ** New option --debug-format=option1[,option2,...] allows one to add
172 additional text to each output. At present only timestamps
173 are supported: --debug-format=timestamps.
174 Timestamps can also be turned on with the
175 "monitor set debug-format timestamps" command from GDB.
177 * The 'record instruction-history' command now starts counting instructions
178 at one. This also affects the instruction ranges reported by the
179 'record function-call-history' command when given the /i modifier.
181 * The command 'record function-call-history' supports a new modifier '/c' to
182 indent the function names based on their call stack depth.
183 The fields for the '/i' and '/l' modifier have been reordered.
184 The source line range is now prefixed with 'at'.
185 The instruction range is now prefixed with 'inst'.
186 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
187 "record instruction-history" and "list" commands.
189 * The ranges given as arguments to the 'record function-call-history' and
190 'record instruction-history' commands are now inclusive.
192 * The btrace record target now supports the 'record goto' command.
193 For locations inside the execution trace, the back trace is computed
194 based on the information stored in the execution trace.
196 * The btrace record target supports limited reverse execution and replay.
197 The target does not record data and therefore does not allow reading
200 * The "catch syscall" command now works on s390*-linux* targets.
202 * The "compare-sections" command is no longer specific to target
203 remote. It now works with all targets.
205 * All native targets are now consistently called "native".
206 Consequently, the "target child", "target GNU", "target djgpp",
207 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
208 commands have been replaced with "target native". The QNX/NTO port
209 leaves the "procfs" target in place and adds a "native" target for
210 consistency with other ports. The impact on users should be minimal
211 as these commands previously either throwed an error, or were
212 no-ops. The target's name is visible in the output of the following
213 commands: "help target", "info target", "info files", "maint print
216 * The "target native" command now connects to the native target. This
217 can be used to launch native programs even when "set
218 auto-connect-native-target" is set to off.
220 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
222 * Support for Intel(R) AVX-512 registers on GNU/Linux.
223 Support displaying and modifying Intel(R) AVX-512 registers
224 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
228 qXfer:btrace:read's annex
229 The qXfer:btrace:read packet supports a new annex 'delta' to read
230 branch trace incrementally.
234 ** Valid Python operations on gdb.Value objects representing
235 structs/classes invoke the corresponding overloaded operators if
237 ** New `Xmethods' feature in the Python API. Xmethods are
238 additional methods or replacements for existing methods of a C++
239 class. This feature is useful for those cases where a method
240 defined in C++ source code could be inlined or optimized out by
241 the compiler, making it unavailable to GDB.
244 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
246 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
247 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
248 its alias "share", instead.
250 * The commands "set remotebaud" and "show remotebaud" are no longer
251 supported. Use "set serial baud" and "show serial baud" (respectively)
256 ** A new option "-gdb-set mi-async" replaces "-gdb-set
257 target-async". The latter is left as a deprecated alias of the
258 former for backward compatibility. If the target supports it,
259 CLI background execution commands are now always possible by
260 default, independently of whether the frontend stated a
261 preference for asynchronous execution with "-gdb-set mi-async".
262 Previously "-gdb-set target-async off" affected both MI execution
263 commands and CLI execution commands.
265 *** Changes in GDB 7.7
267 * Improved support for process record-replay and reverse debugging on
268 arm*-linux* targets. Support for thumb32 and syscall instruction
269 recording has been added.
271 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
273 * GDB now supports Fission DWP file format version 2.
274 http://gcc.gnu.org/wiki/DebugFission
276 * New convenience function "$_isvoid", to check whether an expression
277 is void. A void expression is an expression where the type of the
278 result is "void". For example, some convenience variables may be
279 "void" when evaluated (e.g., "$_exitcode" before the execution of
280 the program being debugged; or an undefined convenience variable).
281 Another example, when calling a function whose return type is
284 * The "maintenance print objfiles" command now takes an optional regexp.
286 * The "catch syscall" command now works on arm*-linux* targets.
288 * GDB now consistently shows "<not saved>" when printing values of
289 registers the debug info indicates have not been saved in the frame
290 and there's nowhere to retrieve them from
291 (callee-saved/call-clobbered registers):
296 (gdb) info registers rax
299 Before, the former would print "<optimized out>", and the latter
300 "*value not available*".
302 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
307 ** Frame filters and frame decorators have been added.
308 ** Temporary breakpoints are now supported.
309 ** Line tables representation has been added.
310 ** New attribute 'parent_type' for gdb.Field objects.
311 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
312 ** New attribute 'name' for gdb.Type objects.
316 Nios II ELF nios2*-*-elf
317 Nios II GNU/Linux nios2*-*-linux
318 Texas Instruments MSP430 msp430*-*-elf
320 * Removed native configurations
322 Support for these a.out NetBSD and OpenBSD obsolete configurations has
323 been removed. ELF variants of these configurations are kept supported.
325 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
326 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
327 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
328 i[34567]86-*-openbsd3.[0-3]
329 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
330 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
331 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
335 Like "catch throw", but catches a re-thrown exception.
337 Renamed from old "maint check-symtabs".
339 Perform consistency checks on symtabs.
341 Expand symtabs matching an optional regexp.
344 Display the details of GDB configure-time options.
346 maint set|show per-command
347 maint set|show per-command space
348 maint set|show per-command time
349 maint set|show per-command symtab
350 Enable display of per-command gdb resource usage.
352 remove-symbol-file FILENAME
353 remove-symbol-file -a ADDRESS
354 Remove a symbol file added via add-symbol-file. The file to remove
355 can be identified by its filename or by an address that lies within
356 the boundaries of this symbol file in memory.
359 info exceptions REGEXP
360 Display the list of Ada exceptions defined in the program being
361 debugged. If provided, only the exceptions whose names match REGEXP
366 set debug symfile off|on
368 Control display of debugging info regarding reading symbol files and
369 symbol tables within those files
371 set print raw frame-arguments
372 show print raw frame-arguments
373 Set/show whether to print frame arguments in raw mode,
374 disregarding any defined pretty-printers.
376 set remote trace-status-packet
377 show remote trace-status-packet
378 Set/show the use of remote protocol qTStatus packet.
382 Control display of debugging messages related to Nios II targets.
386 Control whether target-assisted range stepping is enabled.
388 set startup-with-shell
389 show startup-with-shell
390 Specifies whether Unix child processes are started via a shell or
395 Use the target memory cache for accesses to the code segment. This
396 improves performance of remote debugging (particularly disassembly).
398 * You can now use a literal value 'unlimited' for options that
399 interpret 0 or -1 as meaning "unlimited". E.g., "set
400 trace-buffer-size unlimited" is now an alias for "set
401 trace-buffer-size -1" and "set height unlimited" is now an alias for
404 * The "set debug symtab-create" debugging option of GDB has been changed to
405 accept a verbosity level. 0 means "off", 1 provides basic debugging
406 output, and values of 2 or greater provides more verbose output.
408 * New command-line options
410 Display the details of GDB configure-time options.
412 * The command 'tsave' can now support new option '-ctf' to save trace
413 buffer in Common Trace Format.
415 * Newly installed $prefix/bin/gcore acts as a shell interface for the
418 * GDB now implements the the C++ 'typeid' operator.
420 * The new convenience variable $_exception holds the exception being
421 thrown or caught at an exception-related catchpoint.
423 * The exception-related catchpoints, like "catch throw", now accept a
424 regular expression which can be used to filter exceptions by type.
426 * The new convenience variable $_exitsignal is automatically set to
427 the terminating signal number when the program being debugged dies
428 due to an uncaught signal.
432 ** All MI commands now accept an optional "--language" option.
433 Support for this feature can be verified by using the "-list-features"
434 command, which should contain "language-option".
436 ** The new command -info-gdb-mi-command allows the user to determine
437 whether a GDB/MI command is supported or not.
439 ** The "^error" result record returned when trying to execute an undefined
440 GDB/MI command now provides a variable named "code" whose content is the
441 "undefined-command" error code. Support for this feature can be verified
442 by using the "-list-features" command, which should contain
443 "undefined-command-error-code".
445 ** The -trace-save MI command can optionally save trace buffer in Common
448 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
450 ** The command -data-list-register-values now accepts an optional
451 "--skip-unavailable" option. When used, only the available registers
454 ** The new command -trace-frame-collected dumps collected variables,
455 computed expressions, tvars, memory and registers in a traceframe.
457 ** The commands -stack-list-locals, -stack-list-arguments and
458 -stack-list-variables now accept an option "--skip-unavailable".
459 When used, only the available locals or arguments are displayed.
461 ** The -exec-run command now accepts an optional "--start" option.
462 When used, the command follows the same semantics as the "start"
463 command, stopping the program's execution at the start of its
464 main subprogram. Support for this feature can be verified using
465 the "-list-features" command, which should contain
466 "exec-run-start-option".
468 ** The new commands -catch-assert and -catch-exceptions insert
469 catchpoints stopping the program when Ada exceptions are raised.
471 ** The new command -info-ada-exceptions provides the equivalent of
472 the new "info exceptions" command.
474 * New system-wide configuration scripts
475 A GDB installation now provides scripts suitable for use as system-wide
476 configuration scripts for the following systems:
480 * GDB now supports target-assigned range stepping with remote targets.
481 This improves the performance of stepping source lines by reducing
482 the number of control packets from/to GDB. See "New remote packets"
485 * GDB now understands the element 'tvar' in the XML traceframe info.
486 It has the id of the collected trace state variables.
488 * On S/390 targets that provide the transactional-execution feature,
489 the program interruption transaction diagnostic block (TDB) is now
490 represented as a number of additional "registers" in GDB.
496 The vCont packet supports a new 'r' action, that tells the remote
497 stub to step through an address range itself, without GDB
498 involvemement at each single-step.
500 qXfer:libraries-svr4:read's annex
501 The previously unused annex of the qXfer:libraries-svr4:read packet
502 is now used to support passing an argument list. The remote stub
503 reports support for this argument list to GDB's qSupported query.
504 The defined arguments are "start" and "prev", used to reduce work
505 necessary for library list updating, resulting in significant
508 * New features in the GDB remote stub, GDBserver
510 ** GDBserver now supports target-assisted range stepping. Currently
511 enabled on x86/x86_64 GNU/Linux targets.
513 ** GDBserver now adds element 'tvar' in the XML in the reply to
514 'qXfer:traceframe-info:read'. It has the id of the collected
515 trace state variables.
517 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
520 * New 'z' formatter for printing and examining memory, this displays the
521 value as hexadecimal zero padded on the left to the size of the type.
523 * GDB can now use Windows x64 unwinding data.
525 * The "set remotebaud" command has been replaced by "set serial baud".
526 Similarly, "show remotebaud" has been replaced by "show serial baud".
527 The "set remotebaud" and "show remotebaud" commands are still available
528 to provide backward compatibility with older versions of GDB.
530 *** Changes in GDB 7.6
532 * Target record has been renamed to record-full.
533 Record/replay is now enabled with the "record full" command.
534 This also affects settings that are associated with full record/replay
535 that have been moved from "set/show record" to "set/show record full":
537 set|show record full insn-number-max
538 set|show record full stop-at-limit
539 set|show record full memory-query
541 * A new record target "record-btrace" has been added. The new target
542 uses hardware support to record the control-flow of a process. It
543 does not support replaying the execution, but it implements the
544 below new commands for investigating the recorded execution log.
545 This new recording method can be enabled using:
549 The "record-btrace" target is only available on Intel Atom processors
550 and requires a Linux kernel 2.6.32 or later.
552 * Two new commands have been added for record/replay to give information
553 about the recorded execution without having to replay the execution.
554 The commands are only supported by "record btrace".
556 record instruction-history prints the execution history at
557 instruction granularity
559 record function-call-history prints the execution history at
562 * New native configurations
564 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
565 FreeBSD/powerpc powerpc*-*-freebsd
566 x86_64/Cygwin x86_64-*-cygwin*
567 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
571 ARM AArch64 aarch64*-*-elf
572 ARM AArch64 GNU/Linux aarch64*-*-linux
573 Lynx 178 PowerPC powerpc-*-lynx*178
574 x86_64/Cygwin x86_64-*-cygwin*
575 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
577 * If the configured location of system.gdbinit file (as given by the
578 --with-system-gdbinit option at configure time) is in the
579 data-directory (as specified by --with-gdb-datadir at configure
580 time) or in one of its subdirectories, then GDB will look for the
581 system-wide init file in the directory specified by the
582 --data-directory command-line option.
584 * New command line options:
586 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
587 other initialization files, unlike -nx which disables all of them.
589 * Removed command line options
591 -epoch This was used by the gdb mode in Epoch, an ancient fork of
594 * The 'ptype' and 'whatis' commands now accept an argument to control
597 * 'info proc' now works on some core files.
601 ** Vectors can be created with gdb.Type.vector.
603 ** Python's atexit.register now works in GDB.
605 ** Types can be pretty-printed via a Python API.
607 ** Python 3 is now supported (in addition to Python 2.4 or later)
609 ** New class gdb.Architecture exposes GDB's internal representation
610 of architecture in the Python API.
612 ** New method Frame.architecture returns the gdb.Architecture object
613 corresponding to the frame's architecture.
615 * New Python-based convenience functions:
617 ** $_memeq(buf1, buf2, length)
618 ** $_streq(str1, str2)
620 ** $_regex(str, regex)
622 * The 'cd' command now defaults to using '~' (the home directory) if not
625 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
626 default for GCC since November 2000.
628 * The command 'forward-search' can now be abbreviated as 'fo'.
630 * The command 'info tracepoints' can now display 'installed on target'
631 or 'not installed on target' for each non-pending location of tracepoint.
633 * New configure options
635 --enable-libmcheck/--disable-libmcheck
636 By default, development versions are built with -lmcheck on hosts
637 that support it, in order to help track memory corruption issues.
638 Release versions, on the other hand, are built without -lmcheck
639 by default. The --enable-libmcheck/--disable-libmcheck configure
640 options allow the user to override that default.
641 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
642 This configure option allows the user to build GDB with
643 libbabeltrace using which GDB can read Common Trace Format data.
645 * New commands (for set/show, see "New options" below)
648 Catch signals. This is similar to "handle", but allows commands and
649 conditions to be attached.
652 List the BFDs known to GDB.
654 python-interactive [command]
656 Start a Python interactive prompt, or evaluate the optional command
657 and print the result of expressions.
660 "py" is a new alias for "python".
662 enable type-printer [name]...
663 disable type-printer [name]...
664 Enable or disable type printers.
668 ** For the Renesas Super-H architecture, the "regs" command has been removed
669 (has been deprecated in GDB 7.5), and "info all-registers" should be used
674 set print type methods (on|off)
675 show print type methods
676 Control whether method declarations are displayed by "ptype".
677 The default is to show them.
679 set print type typedefs (on|off)
680 show print type typedefs
681 Control whether typedef definitions are displayed by "ptype".
682 The default is to show them.
684 set filename-display basename|relative|absolute
685 show filename-display
686 Control the way in which filenames is displayed.
687 The default is "relative", which preserves previous behavior.
689 set trace-buffer-size
690 show trace-buffer-size
691 Request target to change the size of trace buffer.
693 set remote trace-buffer-size-packet auto|on|off
694 show remote trace-buffer-size-packet
695 Control the use of the remote protocol `QTBuffer:size' packet.
699 Control display of debugging messages related to ARM AArch64.
702 set debug coff-pe-read
703 show debug coff-pe-read
704 Control display of debugging messages related to reading of COFF/PE
709 Control display of debugging messages related to Mach-O symbols
712 set debug notification
713 show debug notification
714 Control display of debugging info for async remote notification.
718 ** Command parameter changes are now notified using new async record
719 "=cmd-param-changed".
720 ** Trace frame changes caused by command "tfind" are now notified using
721 new async record "=traceframe-changed".
722 ** The creation, deletion and modification of trace state variables
723 are now notified using new async records "=tsv-created",
724 "=tsv-deleted" and "=tsv-modified".
725 ** The start and stop of process record are now notified using new
726 async record "=record-started" and "=record-stopped".
727 ** Memory changes are now notified using new async record
729 ** The data-disassemble command response will include a "fullname" field
730 containing the absolute file name when source has been requested.
731 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
732 command, to allow pattern filling of memory areas.
733 ** New commands "-catch-load"/"-catch-unload" added for intercepting
734 library load/unload events.
735 ** The response to breakpoint commands and breakpoint async records
736 includes an "installed" field containing a boolean state about each
737 non-pending tracepoint location is whether installed on target or not.
738 ** Output of the "-trace-status" command includes a "trace-file" field
739 containing the name of the trace file being examined. This field is
740 optional, and only present when examining a trace file.
741 ** The "fullname" field is now always present along with the "file" field,
742 even if the file cannot be found by GDB.
744 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
745 You must have the LZMA library available when configuring GDB for this
746 feature to be enabled. For more information, see:
747 http://fedoraproject.org/wiki/Features/MiniDebugInfo
752 Set the size of trace buffer. The remote stub reports support for this
753 packet to gdb's qSupported query.
756 Enable Branch Trace Store (BTS)-based branch tracing for the current
757 thread. The remote stub reports support for this packet to gdb's
761 Disable branch tracing for the current thread. The remote stub reports
762 support for this packet to gdb's qSupported query.
765 Read the traced branches for the current thread. The remote stub
766 reports support for this packet to gdb's qSupported query.
768 *** Changes in GDB 7.5
770 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
771 for more x32 ABI info.
773 * GDB now supports access to MIPS DSP registers on Linux targets.
775 * GDB now supports debugging microMIPS binaries.
777 * The "info os" command on GNU/Linux can now display information on
778 several new classes of objects managed by the operating system:
779 "info os procgroups" lists process groups
780 "info os files" lists file descriptors
781 "info os sockets" lists internet-domain sockets
782 "info os shm" lists shared-memory regions
783 "info os semaphores" lists semaphores
784 "info os msg" lists message queues
785 "info os modules" lists loaded kernel modules
787 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
788 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
789 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
790 options and inspect the probe arguments using the new $_probe_arg family
791 of convenience variables. You can obtain more information about SystemTap
792 in <http://sourceware.org/systemtap/>.
794 * GDB now supports reversible debugging on ARM, it allows you to
795 debug basic ARM and THUMB instructions, and provides
796 record/replay support.
798 * The option "symbol-reloading" has been deleted as it is no longer used.
802 ** GDB commands implemented in Python can now be put in command class
805 ** The "maint set python print-stack on|off" is now deleted.
807 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
808 apply "flag enum"-style pretty-printing to any enum.
810 ** gdb.lookup_symbol can now work when there is no current frame.
812 ** gdb.Symbol now has a 'line' attribute, holding the line number in
813 the source at which the symbol was defined.
815 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
816 method 'value'. The former indicates whether the symbol needs a
817 frame in order to compute its value, and the latter computes the
820 ** A new method 'referenced_value' on gdb.Value objects which can
821 dereference pointer as well as C++ reference values.
823 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
824 which return the global and static blocks (as gdb.Block objects),
825 of the underlying symbol table, respectively.
827 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
828 object associated with a PC value.
830 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
831 of the address range occupied by code for the current source line.
833 * Go language support.
834 GDB now supports debugging programs written in the Go programming
837 * GDBserver now supports stdio connections.
838 E.g. (gdb) target remote | ssh myhost gdbserver - hello
840 * The binary "gdbtui" can no longer be built or installed.
841 Use "gdb -tui" instead.
843 * GDB will now print "flag" enums specially. A flag enum is one where
844 all the enumerator values have no bits in common when pairwise
845 "and"ed. When printing a value whose type is a flag enum, GDB will
846 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
847 (gdb) print (enum E) 3
850 * The filename part of a linespec will now match trailing components
851 of a source file name. For example, "break gcc/expr.c:1000" will
852 now set a breakpoint in build/gcc/expr.c, but not
855 * The "info proc" and "generate-core-file" commands will now also
856 work on remote targets connected to GDBserver on Linux.
858 * The command "info catch" has been removed. It has been disabled
861 * The "catch exception" and "catch assert" commands now accept
862 a condition at the end of the command, much like the "break"
863 command does. For instance:
865 (gdb) catch exception Constraint_Error if Barrier = True
867 Previously, it was possible to add a condition to such catchpoints,
868 but it had to be done as a second step, after the catchpoint had been
869 created, using the "condition" command.
871 * The "info static-tracepoint-marker" command will now also work on
872 native Linux targets with in-process agent.
874 * GDB can now set breakpoints on inlined functions.
876 * The .gdb_index section has been updated to include symbols for
877 inlined functions. GDB will ignore older .gdb_index sections by
878 default, which could cause symbol files to be loaded more slowly
879 until their .gdb_index sections can be recreated. The new command
880 "set use-deprecated-index-sections on" will cause GDB to use any older
881 .gdb_index sections it finds. This will restore performance, but the
882 ability to set breakpoints on inlined functions will be lost in symbol
883 files with older .gdb_index sections.
885 The .gdb_index section has also been updated to record more information
886 about each symbol. This speeds up the "info variables", "info functions"
887 and "info types" commands when used with programs having the .gdb_index
888 section, as well as speeding up debugging with shared libraries using
889 the .gdb_index section.
891 * Ada support for GDB/MI Variable Objects has been added.
893 * GDB can now support 'breakpoint always-inserted mode' in 'record'
898 ** New command -info-os is the MI equivalent of "info os".
900 ** Output logs ("set logging" and related) now include MI output.
904 ** "set use-deprecated-index-sections on|off"
905 "show use-deprecated-index-sections on|off"
906 Controls the use of deprecated .gdb_index sections.
908 ** "catch load" and "catch unload" can be used to stop when a shared
909 library is loaded or unloaded, respectively.
911 ** "enable count" can be used to auto-disable a breakpoint after
914 ** "info vtbl" can be used to show the virtual method tables for
915 C++ and Java objects.
917 ** "explore" and its sub commands "explore value" and "explore type"
918 can be used to recursively explore values and types of
919 expressions. These commands are available only if GDB is
920 configured with '--with-python'.
922 ** "info auto-load" shows status of all kinds of auto-loaded files,
923 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
924 sequences of commands files, "info auto-load python-scripts"
925 shows status of auto-loading Python script files,
926 "info auto-load local-gdbinit" shows status of loading init file
927 (.gdbinit) from current directory and "info auto-load libthread-db" shows
928 status of inferior specific thread debugging shared library loading.
930 ** "info auto-load-scripts", "set auto-load-scripts on|off"
931 and "show auto-load-scripts" commands have been deprecated, use their
932 "info auto-load python-scripts", "set auto-load python-scripts on|off"
933 and "show auto-load python-scripts" counterparts instead.
935 ** "dprintf location,format,args..." creates a dynamic printf, which
936 is basically a breakpoint that does a printf and immediately
937 resumes your program's execution, so it is like a printf that you
938 can insert dynamically at runtime instead of at compiletime.
940 ** "set print symbol"
942 Controls whether GDB attempts to display the symbol, if any,
943 corresponding to addresses it prints. This defaults to "on", but
944 you can set it to "off" to restore GDB's previous behavior.
946 * Deprecated commands
948 ** For the Renesas Super-H architecture, the "regs" command has been
949 deprecated, and "info all-registers" should be used instead.
953 Renesas RL78 rl78-*-elf
954 HP OpenVMS ia64 ia64-hp-openvms*
956 * GDBserver supports evaluation of breakpoint conditions. When
957 support is advertised by GDBserver, GDB may be told to send the
958 breakpoint conditions in bytecode form to GDBserver. GDBserver
959 will only report the breakpoint trigger to GDB when its condition
965 show mips compression
966 Select the compressed ISA encoding used in functions that have no symbol
967 information available. The encoding can be set to either of:
970 and is updated automatically from ELF file flags if available.
972 set breakpoint condition-evaluation
973 show breakpoint condition-evaluation
974 Control whether breakpoint conditions are evaluated by GDB ("host") or by
975 GDBserver ("target"). Default option "auto" chooses the most efficient
977 This option can improve debugger efficiency depending on the speed of the
981 Disable auto-loading globally.
984 Show auto-loading setting of all kinds of auto-loaded files.
986 set auto-load gdb-scripts on|off
987 show auto-load gdb-scripts
988 Control auto-loading of GDB canned sequences of commands files.
990 set auto-load python-scripts on|off
991 show auto-load python-scripts
992 Control auto-loading of Python script files.
994 set auto-load local-gdbinit on|off
995 show auto-load local-gdbinit
996 Control loading of init file (.gdbinit) from current directory.
998 set auto-load libthread-db on|off
999 show auto-load libthread-db
1000 Control auto-loading of inferior specific thread debugging shared library.
1002 set auto-load scripts-directory <dir1>[:<dir2>...]
1003 show auto-load scripts-directory
1004 Set a list of directories from which to load auto-loaded scripts.
1005 Automatically loaded Python scripts and GDB scripts are located in one
1006 of the directories listed by this option.
1007 The delimiter (':' above) may differ according to the host platform.
1009 set auto-load safe-path <dir1>[:<dir2>...]
1010 show auto-load safe-path
1011 Set a list of directories from which it is safe to auto-load files.
1012 The delimiter (':' above) may differ according to the host platform.
1014 set debug auto-load on|off
1015 show debug auto-load
1016 Control display of debugging info for auto-loading the files above.
1018 set dprintf-style gdb|call|agent
1020 Control the way in which a dynamic printf is performed; "gdb"
1021 requests a GDB printf command, while "call" causes dprintf to call a
1022 function in the inferior. "agent" requests that the target agent
1023 (such as GDBserver) do the printing.
1025 set dprintf-function <expr>
1026 show dprintf-function
1027 set dprintf-channel <expr>
1028 show dprintf-channel
1029 Set the function and optional first argument to the call when using
1030 the "call" style of dynamic printf.
1032 set disconnected-dprintf on|off
1033 show disconnected-dprintf
1034 Control whether agent-style dynamic printfs continue to be in effect
1035 after GDB disconnects.
1037 * New configure options
1039 --with-auto-load-dir
1040 Configure default value for the 'set auto-load scripts-directory'
1041 setting above. It defaults to '$debugdir:$datadir/auto-load',
1042 $debugdir representing global debugging info directories (available
1043 via 'show debug-file-directory') and $datadir representing GDB's data
1044 directory (available via 'show data-directory').
1046 --with-auto-load-safe-path
1047 Configure default value for the 'set auto-load safe-path' setting
1048 above. It defaults to the --with-auto-load-dir setting.
1050 --without-auto-load-safe-path
1051 Set 'set auto-load safe-path' to '/', effectively disabling this
1054 * New remote packets
1056 z0/z1 conditional breakpoints extension
1058 The z0/z1 breakpoint insertion packets have been extended to carry
1059 a list of conditional expressions over to the remote stub depending on the
1060 condition evaluation mode. The use of this extension can be controlled
1061 via the "set remote conditional-breakpoints-packet" command.
1065 Specify the signals which the remote stub may pass to the debugged
1066 program without GDB involvement.
1068 * New command line options
1070 --init-command=FILE, -ix Like --command, -x but execute it
1071 before loading inferior.
1072 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1073 execute it before loading inferior.
1075 *** Changes in GDB 7.4
1077 * GDB now handles ambiguous linespecs more consistently; the existing
1078 FILE:LINE support has been expanded to other types of linespecs. A
1079 breakpoint will now be set on all matching locations in all
1080 inferiors, and locations will be added or removed according to
1083 * GDB now allows you to skip uninteresting functions and files when
1084 stepping with the "skip function" and "skip file" commands.
1086 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1087 and "show remote hardware-watchpoint-length-limit". These allows to
1088 set or show the maximum length limit (in bytes) of a remote
1089 target hardware watchpoint.
1091 This allows e.g. to use "unlimited" hardware watchpoints with the
1092 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1093 watchpoints are slower than real hardware watchpoints but are
1094 significantly faster than gdb software watchpoints.
1098 ** The register_pretty_printer function in module gdb.printing now takes
1099 an optional `replace' argument. If True, the new printer replaces any
1102 ** The "maint set python print-stack on|off" command has been
1103 deprecated and will be deleted in GDB 7.5.
1104 A new command: "set python print-stack none|full|message" has
1105 replaced it. Additionally, the default for "print-stack" is
1106 now "message", which just prints the error message without
1109 ** A prompt substitution hook (prompt_hook) is now available to the
1112 ** A new Python module, gdb.prompt has been added to the GDB Python
1113 modules library. This module provides functionality for
1114 escape sequences in prompts (used by set/show
1115 extended-prompt). These escape sequences are replaced by their
1116 corresponding value.
1118 ** Python commands and convenience-functions located in
1119 'data-directory'/python/gdb/command and
1120 'data-directory'/python/gdb/function are now automatically loaded
1123 ** Blocks now provide four new attributes. global_block and
1124 static_block will return the global and static blocks
1125 respectively. is_static and is_global are boolean attributes
1126 that indicate if the block is one of those two types.
1128 ** Symbols now provide the "type" attribute, the type of the symbol.
1130 ** The "gdb.breakpoint" function has been deprecated in favor of
1133 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1134 of a function. This class is based on the "finish" command
1135 available in the CLI.
1137 ** Type objects for struct and union types now allow access to
1138 the fields using standard Python dictionary (mapping) methods.
1139 For example, "some_type['myfield']" now works, as does
1140 "some_type.items()".
1142 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1145 ** A new function, "deep_items" has been added to the gdb.types
1146 module in the GDB Python modules library. This function returns
1147 an iterator over the fields of a struct or union type. Unlike
1148 the standard Python "iteritems" method, it will recursively traverse
1149 any anonymous fields.
1153 ** "*stopped" events can report several new "reason"s, such as
1156 ** Breakpoint changes are now notified using new async records, like
1157 "=breakpoint-modified".
1159 ** New command -ada-task-info.
1161 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1162 $sdir specifies the default system locations of shared libraries.
1163 $pdir specifies the directory where the libpthread used by the application
1166 GDB no longer looks in $sdir and $pdir after it has searched the directories
1167 mentioned in libthread-db-search-path. If you want to search those
1168 directories, they must be specified in libthread-db-search-path.
1169 The default value of libthread-db-search-path on GNU/Linux and Solaris
1170 systems is now "$sdir:$pdir".
1172 $pdir is not supported by gdbserver, it is currently ignored.
1173 $sdir is supported by gdbserver.
1175 * New configure option --with-iconv-bin.
1176 When using the internationalization support like the one in the GNU C
1177 library, GDB will invoke the "iconv" program to get a list of supported
1178 character sets. If this program lives in a non-standard location, one can
1179 use this option to specify where to find it.
1181 * When natively debugging programs on PowerPC BookE processors running
1182 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1183 watchpoints, which specify a mask in addition to an address to watch.
1184 The mask specifies that some bits of an address (the bits which are
1185 reset in the mask) should be ignored when matching the address accessed
1186 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1187 section in the user manual for more details.
1189 * The new option --once causes GDBserver to stop listening for connections once
1190 the first connection is made. The listening port used by GDBserver will
1191 become available after that.
1193 * New commands "info macros" and "alias" have been added.
1195 * New function parameters suffix @entry specifies value of function parameter
1196 at the time the function got called. Entry values are available only since
1202 "!" is now an alias of the "shell" command.
1203 Note that no space is needed between "!" and SHELL COMMAND.
1207 watch EXPRESSION mask MASK_VALUE
1208 The watch command now supports the mask argument which allows creation
1209 of masked watchpoints, if the current architecture supports this feature.
1211 info auto-load-scripts [REGEXP]
1212 This command was formerly named "maintenance print section-scripts".
1213 It is now generally useful and is no longer a maintenance-only command.
1215 info macro [-all] [--] MACRO
1216 The info macro command has new options `-all' and `--'. The first for
1217 printing all definitions of a macro. The second for explicitly specifying
1218 the end of arguments and the beginning of the macro name in case the macro
1219 name starts with a hyphen.
1221 collect[/s] EXPRESSIONS
1222 The tracepoint collect command now takes an optional modifier "/s"
1223 that directs it to dereference pointer-to-character types and
1224 collect the bytes of memory up to a zero byte. The behavior is
1225 similar to what you see when you use the regular print command on a
1226 string. An optional integer following the "/s" sets a bound on the
1227 number of bytes that will be collected.
1230 The trace start command now interprets any supplied arguments as a
1231 note to be recorded with the trace run, with an effect similar to
1232 setting the variable trace-notes.
1235 The trace stop command now interprets any arguments as a note to be
1236 mentioned along with the tstatus report that the trace was stopped
1237 with a command. The effect is similar to setting the variable
1240 * Tracepoints can now be enabled and disabled at any time after a trace
1241 experiment has been started using the standard "enable" and "disable"
1242 commands. It is now possible to start a trace experiment with no enabled
1243 tracepoints; GDB will display a warning, but will allow the experiment to
1244 begin, assuming that tracepoints will be enabled as needed while the trace
1247 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1248 locations with 4-byte instructions, when they were previously
1249 limited to locations with instructions of 5 bytes or longer.
1253 set debug dwarf2-read
1254 show debug dwarf2-read
1255 Turns on or off display of debugging messages related to reading
1256 DWARF debug info. The default is off.
1258 set debug symtab-create
1259 show debug symtab-create
1260 Turns on or off display of debugging messages related to symbol table
1261 creation. The default is off.
1264 show extended-prompt
1265 Set the GDB prompt, and allow escape sequences to be inserted to
1266 display miscellaneous information (see 'help set extended-prompt'
1267 for the list of sequences). This prompt (and any information
1268 accessed through the escape sequences) is updated every time the
1269 prompt is displayed.
1271 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1272 show print entry-values
1273 Set printing of frame argument values at function entry. In some cases
1274 GDB can determine the value of function argument which was passed by the
1275 function caller, even if the value was modified inside the called function.
1277 set debug entry-values
1278 show debug entry-values
1279 Control display of debugging info for determining frame argument values at
1280 function entry and virtual tail call frames.
1282 set basenames-may-differ
1283 show basenames-may-differ
1284 Set whether a source file may have multiple base names.
1285 (A "base name" is the name of a file with the directory part removed.
1286 Example: The base name of "/home/user/hello.c" is "hello.c".)
1287 If set, GDB will canonicalize file names (e.g., expand symlinks)
1288 before comparing them. Canonicalization is an expensive operation,
1289 but it allows the same file be known by more than one base name.
1290 If not set (the default), all source files are assumed to have just
1291 one base name, and gdb will do file name comparisons more efficiently.
1297 Set a user name and notes for the current and any future trace runs.
1298 This is useful for long-running and/or disconnected traces, to
1299 inform others (or yourself) as to who is running the trace, supply
1300 contact information, or otherwise explain what is going on.
1302 set trace-stop-notes
1303 show trace-stop-notes
1304 Set a note attached to the trace run, that is displayed when the
1305 trace has been stopped by a tstop command. This is useful for
1306 instance as an explanation, if you are stopping a trace run that was
1307 started by someone else.
1309 * New remote packets
1313 Dynamically enable a tracepoint in a started trace experiment.
1317 Dynamically disable a tracepoint in a started trace experiment.
1321 Set the user and notes of the trace run.
1325 Query the current status of a tracepoint.
1329 Query the minimum length of instruction at which a fast tracepoint may
1332 * Dcache size (number of lines) and line-size are now runtime-configurable
1333 via "set dcache line" and "set dcache line-size" commands.
1337 Texas Instruments TMS320C6x tic6x-*-*
1341 Renesas RL78 rl78-*-elf
1343 *** Changes in GDB 7.3.1
1345 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1347 *** Changes in GDB 7.3
1349 * GDB has a new command: "thread find [REGEXP]".
1350 It finds the thread id whose name, target id, or thread extra info
1351 matches the given regular expression.
1353 * The "catch syscall" command now works on mips*-linux* targets.
1355 * The -data-disassemble MI command now supports modes 2 and 3 for
1356 dumping the instruction opcodes.
1358 * New command line options
1360 -data-directory DIR Specify DIR as the "data-directory".
1361 This is mostly for testing purposes.
1363 * The "maint set python auto-load on|off" command has been renamed to
1364 "set auto-load-scripts on|off".
1366 * GDB has a new command: "set directories".
1367 It is like the "dir" command except that it replaces the
1368 source path list instead of augmenting it.
1370 * GDB now understands thread names.
1372 On GNU/Linux, "info threads" will display the thread name as set by
1373 prctl or pthread_setname_np.
1375 There is also a new command, "thread name", which can be used to
1376 assign a name internally for GDB to display.
1379 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1380 has been integrated into GDB.
1384 ** The function gdb.Write now accepts an optional keyword 'stream'.
1385 This keyword, when provided, will direct the output to either
1386 stdout, stderr, or GDB's logging output.
1388 ** Parameters can now be be sub-classed in Python, and in particular
1389 you may implement the get_set_doc and get_show_doc functions.
1390 This improves how Parameter set/show documentation is processed
1391 and allows for more dynamic content.
1393 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1394 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1395 have an is_valid method.
1397 ** Breakpoints can now be sub-classed in Python, and in particular
1398 you may implement a 'stop' function that is executed each time
1399 the inferior reaches that breakpoint.
1401 ** New function gdb.lookup_global_symbol looks up a global symbol.
1403 ** GDB values in Python are now callable if the value represents a
1404 function. For example, if 'some_value' represents a function that
1405 takes two integer parameters and returns a value, you can call
1406 that function like so:
1408 result = some_value (10,20)
1410 ** Module gdb.types has been added.
1411 It contains a collection of utilities for working with gdb.Types objects:
1412 get_basic_type, has_field, make_enum_dict.
1414 ** Module gdb.printing has been added.
1415 It contains utilities for writing and registering pretty-printers.
1416 New classes: PrettyPrinter, SubPrettyPrinter,
1417 RegexpCollectionPrettyPrinter.
1418 New function: register_pretty_printer.
1420 ** New commands "info pretty-printers", "enable pretty-printer" and
1421 "disable pretty-printer" have been added.
1423 ** gdb.parameter("directories") is now available.
1425 ** New function gdb.newest_frame returns the newest frame in the
1428 ** The gdb.InferiorThread class has a new "name" attribute. This
1429 holds the thread's name.
1431 ** Python Support for Inferior events.
1432 Python scripts can add observers to be notified of events
1433 occurring in the process being debugged.
1434 The following events are currently supported:
1435 - gdb.events.cont Continue event.
1436 - gdb.events.exited Inferior exited event.
1437 - gdb.events.stop Signal received, and Breakpoint hit events.
1441 ** GDB now puts template parameters in scope when debugging in an
1442 instantiation. For example, if you have:
1444 template<int X> int func (void) { return X; }
1446 then if you step into func<5>, "print X" will show "5". This
1447 feature requires proper debuginfo support from the compiler; it
1448 was added to GCC 4.5.
1450 ** The motion commands "next", "finish", "until", and "advance" now
1451 work better when exceptions are thrown. In particular, GDB will
1452 no longer lose control of the inferior; instead, the GDB will
1453 stop the inferior at the point at which the exception is caught.
1454 This functionality requires a change in the exception handling
1455 code that was introduced in GCC 4.5.
1457 * GDB now follows GCC's rules on accessing volatile objects when
1458 reading or writing target state during expression evaluation.
1459 One notable difference to prior behavior is that "print x = 0"
1460 no longer generates a read of x; the value of the assignment is
1461 now always taken directly from the value being assigned.
1463 * GDB now has some support for using labels in the program's source in
1464 linespecs. For instance, you can use "advance label" to continue
1465 execution to a label.
1467 * GDB now has support for reading and writing a new .gdb_index
1468 section. This section holds a fast index of DWARF debugging
1469 information and can be used to greatly speed up GDB startup and
1470 operation. See the documentation for `save gdb-index' for details.
1472 * The "watch" command now accepts an optional "-location" argument.
1473 When used, this causes GDB to watch the memory referred to by the
1474 expression. Such a watchpoint is never deleted due to it going out
1477 * GDB now supports thread debugging of core dumps on GNU/Linux.
1479 GDB now activates thread debugging using the libthread_db library
1480 when debugging GNU/Linux core dumps, similarly to when debugging
1481 live processes. As a result, when debugging a core dump file, GDB
1482 is now able to display pthread_t ids of threads. For example, "info
1483 threads" shows the same output as when debugging the process when it
1484 was live. In earlier releases, you'd see something like this:
1487 * 1 LWP 6780 main () at main.c:10
1489 While now you see this:
1492 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1494 It is also now possible to inspect TLS variables when debugging core
1497 When debugging a core dump generated on a machine other than the one
1498 used to run GDB, you may need to point GDB at the correct
1499 libthread_db library with the "set libthread-db-search-path"
1500 command. See the user manual for more details on this command.
1502 * When natively debugging programs on PowerPC BookE processors running
1503 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1504 which stop execution of the inferior whenever it executes an instruction
1505 at any address within the specified range. See the "PowerPC Embedded"
1506 section in the user manual for more details.
1508 * New features in the GDB remote stub, GDBserver
1510 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1511 and i686 LynxOS (version 5.x).
1513 ** GDBserver is now supported on Blackfin Linux.
1515 * New native configurations
1517 ia64 HP-UX ia64-*-hpux*
1521 Analog Devices, Inc. Blackfin Processor bfin-*
1523 * Ada task switching is now supported on sparc-elf targets when
1524 debugging a program using the Ravenscar Profile. For more information,
1525 see the "Tasking Support when using the Ravenscar Profile" section
1526 in the GDB user manual.
1528 * Guile support was removed.
1530 * New features in the GNU simulator
1532 ** The --map-info flag lists all known core mappings.
1534 ** CFI flashes may be simulated via the "cfi" device.
1536 *** Changes in GDB 7.2
1538 * Shared library support for remote targets by default
1540 When GDB is configured for a generic, non-OS specific target, like
1541 for example, --target=arm-eabi or one of the many *-*-elf targets,
1542 GDB now queries remote stubs for loaded shared libraries using the
1543 `qXfer:libraries:read' packet. Previously, shared library support
1544 was always disabled for such configurations.
1548 ** Argument Dependent Lookup (ADL)
1550 In C++ ADL lookup directs function search to the namespaces of its
1551 arguments even if the namespace has not been imported.
1561 Here the compiler will search for `foo' in the namespace of 'b'
1562 and find A::foo. GDB now supports this. This construct is commonly
1563 used in the Standard Template Library for operators.
1565 ** Improved User Defined Operator Support
1567 In addition to member operators, GDB now supports lookup of operators
1568 defined in a namespace and imported with a `using' directive, operators
1569 defined in the global scope, operators imported implicitly from an
1570 anonymous namespace, and the ADL operators mentioned in the previous
1572 GDB now also supports proper overload resolution for all the previously
1573 mentioned flavors of operators.
1575 ** static const class members
1577 Printing of static const class members that are initialized in the
1578 class definition has been fixed.
1580 * Windows Thread Information Block access.
1582 On Windows targets, GDB now supports displaying the Windows Thread
1583 Information Block (TIB) structure. This structure is visible either
1584 by using the new command `info w32 thread-information-block' or, by
1585 dereferencing the new convenience variable named `$_tlb', a
1586 thread-specific pointer to the TIB. This feature is also supported
1587 when remote debugging using GDBserver.
1589 * Static tracepoints
1591 Static tracepoints are calls in the user program into a tracing
1592 library. One such library is a port of the LTTng kernel tracer to
1593 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1594 When debugging with GDBserver, GDB now supports combining the GDB
1595 tracepoint machinery with such libraries. For example: the user can
1596 use GDB to probe a static tracepoint marker (a call from the user
1597 program into the tracing library) with the new "strace" command (see
1598 "New commands" below). This creates a "static tracepoint" in the
1599 breakpoint list, that can be manipulated with the same feature set
1600 as fast and regular tracepoints. E.g., collect registers, local and
1601 global variables, collect trace state variables, and define
1602 tracepoint conditions. In addition, the user can collect extra
1603 static tracepoint marker specific data, by collecting the new
1604 $_sdata internal variable. When analyzing the trace buffer, you can
1605 inspect $_sdata like any other variable available to GDB. For more
1606 information, see the "Tracepoints" chapter in GDB user manual. New
1607 remote packets have been defined to support static tracepoints, see
1608 the "New remote packets" section below.
1610 * Better reconstruction of tracepoints after disconnected tracing
1612 GDB will attempt to download the original source form of tracepoint
1613 definitions when starting a trace run, and then will upload these
1614 upon reconnection to the target, resulting in a more accurate
1615 reconstruction of the tracepoints that are in use on the target.
1619 You can now exercise direct control over the ways that GDB can
1620 affect your program. For instance, you can disallow the setting of
1621 breakpoints, so that the program can run continuously (assuming
1622 non-stop mode). In addition, the "observer" variable is available
1623 to switch all of the different controls; in observer mode, GDB
1624 cannot affect the target's behavior at all, which is useful for
1625 tasks like diagnosing live systems in the field.
1627 * The new convenience variable $_thread holds the number of the
1630 * New remote packets
1634 Return the address of the Windows Thread Information Block of a given thread.
1638 In response to several of the tracepoint packets, the target may now
1639 also respond with a number of intermediate `qRelocInsn' request
1640 packets before the final result packet, to have GDB handle
1641 relocating an instruction to execute at a different address. This
1642 is particularly useful for stubs that support fast tracepoints. GDB
1643 reports support for this feature in the qSupported packet.
1647 List static tracepoint markers in the target program.
1651 List static tracepoint markers at a given address in the target
1654 qXfer:statictrace:read
1656 Read the static trace data collected (by a `collect $_sdata'
1657 tracepoint action). The remote stub reports support for this packet
1658 to gdb's qSupported query.
1662 Send the current settings of GDB's permission flags.
1666 Send part of the source (textual) form of a tracepoint definition,
1667 which includes location, conditional, and action list.
1669 * The source command now accepts a -s option to force searching for the
1670 script in the source search path even if the script name specifies
1673 * New features in the GDB remote stub, GDBserver
1675 - GDBserver now support tracepoints (including fast tracepoints, and
1676 static tracepoints). The feature is currently supported by the
1677 i386-linux and amd64-linux builds. See the "Tracepoints support
1678 in gdbserver" section in the manual for more information.
1680 GDBserver JIT compiles the tracepoint's conditional agent
1681 expression bytecode into native code whenever possible for low
1682 overhead dynamic tracepoints conditionals. For such tracepoints,
1683 an expression that examines program state is evaluated when the
1684 tracepoint is reached, in order to determine whether to capture
1685 trace data. If the condition is simple and false, processing the
1686 tracepoint finishes very quickly and no data is gathered.
1688 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1689 for static tracepoints support.
1691 - GDBserver now supports x86_64 Windows 64-bit debugging.
1693 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1694 it understands register description.
1696 * The --batch flag now disables pagination and queries.
1698 * X86 general purpose registers
1700 GDB now supports reading/writing byte, word and double-word x86
1701 general purpose registers directly. This means you can use, say,
1702 $ah or $ax to refer, respectively, to the byte register AH and
1703 16-bit word register AX that are actually portions of the 32-bit
1704 register EAX or 64-bit register RAX.
1706 * The `commands' command now accepts a range of breakpoints to modify.
1707 A plain `commands' following a command that creates multiple
1708 breakpoints affects all the breakpoints set by that command. This
1709 applies to breakpoints set by `rbreak', and also applies when a
1710 single `break' command creates multiple breakpoints (e.g.,
1711 breakpoints on overloaded c++ functions).
1713 * The `rbreak' command now accepts a filename specification as part of
1714 its argument, limiting the functions selected by the regex to those
1715 in the specified file.
1717 * Support for remote debugging Windows and SymbianOS shared libraries
1718 from Unix hosts has been improved. Non Windows GDB builds now can
1719 understand target reported file names that follow MS-DOS based file
1720 system semantics, such as file names that include drive letters and
1721 use the backslash character as directory separator. This makes it
1722 possible to transparently use the "set sysroot" and "set
1723 solib-search-path" on Unix hosts to point as host copies of the
1724 target's shared libraries. See the new command "set
1725 target-file-system-kind" described below, and the "Commands to
1726 specify files" section in the user manual for more information.
1730 eval template, expressions...
1731 Convert the values of one or more expressions under the control
1732 of the string template to a command line, and call it.
1734 set target-file-system-kind unix|dos-based|auto
1735 show target-file-system-kind
1736 Set or show the assumed file system kind for target reported file
1739 save breakpoints <filename>
1740 Save all current breakpoint definitions to a file suitable for use
1741 in a later debugging session. To read the saved breakpoint
1742 definitions, use the `source' command.
1744 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1747 info static-tracepoint-markers
1748 Display information about static tracepoint markers in the target.
1750 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1751 Define a static tracepoint by probing a marker at the given
1752 function, line, address, or marker ID.
1756 Enable and disable observer mode.
1758 set may-write-registers on|off
1759 set may-write-memory on|off
1760 set may-insert-breakpoints on|off
1761 set may-insert-tracepoints on|off
1762 set may-insert-fast-tracepoints on|off
1763 set may-interrupt on|off
1764 Set individual permissions for GDB effects on the target. Note that
1765 some of these settings can have undesirable or surprising
1766 consequences, particularly when changed in the middle of a session.
1767 For instance, disabling the writing of memory can prevent
1768 breakpoints from being inserted, cause single-stepping to fail, or
1769 even crash your program, if you disable after breakpoints have been
1770 inserted. However, GDB should not crash.
1772 set record memory-query on|off
1773 show record memory-query
1774 Control whether to stop the inferior if memory changes caused
1775 by an instruction cannot be recorded.
1780 The disassemble command now supports "start,+length" form of two arguments.
1784 ** GDB now provides a new directory location, called the python directory,
1785 where Python scripts written for GDB can be installed. The location
1786 of that directory is <data-directory>/python, where <data-directory>
1787 is the GDB data directory. For more details, see section `Scripting
1788 GDB using Python' in the manual.
1790 ** The GDB Python API now has access to breakpoints, symbols, symbol
1791 tables, program spaces, inferiors, threads and frame's code blocks.
1792 Additionally, GDB Parameters can now be created from the API, and
1793 manipulated via set/show in the CLI.
1795 ** New functions gdb.target_charset, gdb.target_wide_charset,
1796 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1798 ** New exception gdb.GdbError.
1800 ** Pretty-printers are now also looked up in the current program space.
1802 ** Pretty-printers can now be individually enabled and disabled.
1804 ** GDB now looks for names of Python scripts to auto-load in a
1805 special section named `.debug_gdb_scripts', in addition to looking
1806 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1808 * Tracepoint actions were unified with breakpoint commands. In particular,
1809 there are no longer differences in "info break" output for breakpoints and
1810 tracepoints and the "commands" command can be used for both tracepoints and
1811 regular breakpoints.
1815 ARM Symbian arm*-*-symbianelf*
1817 * D language support.
1818 GDB now supports debugging programs written in the D programming
1821 * GDB now supports the extended ptrace interface for PowerPC which is
1822 available since Linux kernel version 2.6.34. This automatically enables
1823 any hardware breakpoints and additional hardware watchpoints available in
1824 the processor. The old ptrace interface exposes just one hardware
1825 watchpoint and no hardware breakpoints.
1827 * GDB is now able to use the Data Value Compare (DVC) register available on
1828 embedded PowerPC processors to implement in hardware simple watchpoint
1829 conditions of the form:
1831 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1833 This works in native GDB running on Linux kernels with the extended ptrace
1834 interface mentioned above.
1836 *** Changes in GDB 7.1
1840 ** Namespace Support
1842 GDB now supports importing of namespaces in C++. This enables the
1843 user to inspect variables from imported namespaces. Support for
1844 namepace aliasing has also been added. So, if a namespace is
1845 aliased in the current scope (e.g. namepace C=A; ) the user can
1846 print variables using the alias (e.g. (gdb) print C::x).
1850 All known bugs relating to the printing of virtual base class were
1851 fixed. It is now possible to call overloaded static methods using a
1856 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1857 and reinterpret_cast<> are now handled by the C++ expression parser.
1861 Xilinx MicroBlaze microblaze-*-*
1866 Xilinx MicroBlaze microblaze
1869 * Multi-program debugging.
1871 GDB now has support for multi-program (a.k.a. multi-executable or
1872 multi-exec) debugging. This allows for debugging multiple inferiors
1873 simultaneously each running a different program under the same GDB
1874 session. See "Debugging Multiple Inferiors and Programs" in the
1875 manual for more information. This implied some user visible changes
1876 in the multi-inferior support. For example, "info inferiors" now
1877 lists inferiors that are not running yet or that have exited
1878 already. See also "New commands" and "New options" below.
1880 * New tracing features
1882 GDB's tracepoint facility now includes several new features:
1884 ** Trace state variables
1886 GDB tracepoints now include support for trace state variables, which
1887 are variables managed by the target agent during a tracing
1888 experiment. They are useful for tracepoints that trigger each
1889 other, so for instance one tracepoint can count hits in a variable,
1890 and then a second tracepoint has a condition that is true when the
1891 count reaches a particular value. Trace state variables share the
1892 $-syntax of GDB convenience variables, and can appear in both
1893 tracepoint actions and condition expressions. Use the "tvariable"
1894 command to create, and "info tvariables" to view; see "Trace State
1895 Variables" in the manual for more detail.
1899 GDB now includes an option for defining fast tracepoints, which
1900 targets may implement more efficiently, such as by installing a jump
1901 into the target agent rather than a trap instruction. The resulting
1902 speedup can be by two orders of magnitude or more, although the
1903 tradeoff is that some program locations on some target architectures
1904 might not allow fast tracepoint installation, for instance if the
1905 instruction to be replaced is shorter than the jump. To request a
1906 fast tracepoint, use the "ftrace" command, with syntax identical to
1907 the regular trace command.
1909 ** Disconnected tracing
1911 It is now possible to detach GDB from the target while it is running
1912 a trace experiment, then reconnect later to see how the experiment
1913 is going. In addition, a new variable disconnected-tracing lets you
1914 tell the target agent whether to continue running a trace if the
1915 connection is lost unexpectedly.
1919 GDB now has the ability to save the trace buffer into a file, and
1920 then use that file as a target, similarly to you can do with
1921 corefiles. You can select trace frames, print data that was
1922 collected in them, and use tstatus to display the state of the
1923 tracing run at the moment that it was saved. To create a trace
1924 file, use "tsave <filename>", and to use it, do "target tfile
1927 ** Circular trace buffer
1929 You can ask the target agent to handle the trace buffer as a
1930 circular buffer, discarding the oldest trace frames to make room for
1931 newer ones, by setting circular-trace-buffer to on. This feature may
1932 not be available for all target agents.
1937 The disassemble command, when invoked with two arguments, now requires
1938 the arguments to be comma-separated.
1941 The info variables command now displays variable definitions. Files
1942 which only declare a variable are not shown.
1945 The source command is now capable of sourcing Python scripts.
1946 This feature is dependent on the debugger being build with Python
1949 Related to this enhancement is also the introduction of a new command
1950 "set script-extension" (see below).
1952 * New commands (for set/show, see "New options" below)
1954 record save [<FILENAME>]
1955 Save a file (in core file format) containing the process record
1956 execution log for replay debugging at a later time.
1958 record restore <FILENAME>
1959 Restore the process record execution log that was saved at an
1960 earlier time, for replay debugging.
1962 add-inferior [-copies <N>] [-exec <FILENAME>]
1965 clone-inferior [-copies <N>] [ID]
1966 Make a new inferior ready to execute the same program another
1967 inferior has loaded.
1972 maint info program-spaces
1973 List the program spaces loaded into GDB.
1975 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1976 show remote interrupt-sequence
1977 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1978 as the sequence to the remote target in order to interrupt the execution.
1979 Ctrl-C is a default. Some system prefers BREAK which is high level of
1980 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1981 Magic SysRq g. It is BREAK signal and character 'g'.
1983 set remote interrupt-on-connect [on | off]
1984 show remote interrupt-on-connect
1985 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1986 remote target when gdb connects to it. This is needed when you debug
1989 set remotebreak [on | off]
1991 Deprecated. Use "set/show remote interrupt-sequence" instead.
1993 tvariable $NAME [ = EXP ]
1994 Create or modify a trace state variable.
1997 List trace state variables and their values.
1999 delete tvariable $NAME ...
2000 Delete one or more trace state variables.
2003 Evaluate the given expressions without collecting anything into the
2004 trace buffer. (Valid in tracepoint actions only.)
2006 ftrace FN / FILE:LINE / *ADDR
2007 Define a fast tracepoint at the given function, line, or address.
2009 * New expression syntax
2011 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2012 GDB now parses 0b101010 identically with 42.
2016 set follow-exec-mode new|same
2017 show follow-exec-mode
2018 Control whether GDB reuses the same inferior across an exec call or
2019 creates a new one. This is useful to be able to restart the old
2020 executable after the inferior having done an exec call.
2022 set default-collect EXPR, ...
2023 show default-collect
2024 Define a list of expressions to be collected at each tracepoint.
2025 This is a useful way to ensure essential items are not overlooked,
2026 such as registers or a critical global variable.
2028 set disconnected-tracing
2029 show disconnected-tracing
2030 If set to 1, the target is instructed to continue tracing if it
2031 loses its connection to GDB. If 0, the target is to stop tracing
2034 set circular-trace-buffer
2035 show circular-trace-buffer
2036 If set to on, the target is instructed to use a circular trace buffer
2037 and discard the oldest trace frames instead of stopping the trace due
2038 to a full trace buffer. If set to off, the trace stops when the buffer
2039 fills up. Some targets may not support this.
2041 set script-extension off|soft|strict
2042 show script-extension
2043 If set to "off", the debugger does not perform any script language
2044 recognition, and all sourced files are assumed to be GDB scripts.
2045 If set to "soft" (the default), files are sourced according to
2046 filename extension, falling back to GDB scripts if the first
2048 If set to "strict", files are sourced according to filename extension.
2050 set ada trust-PAD-over-XVS on|off
2051 show ada trust-PAD-over-XVS
2052 If off, activate a workaround against a bug in the debugging information
2053 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2054 the GCC sources for more information about the GNAT encoding and
2055 PAD types in particular). It is always safe to set this option to
2056 off, but this introduces a slight performance penalty. The default
2059 * Python API Improvements
2061 ** GDB provides the new class gdb.LazyString. This is useful in
2062 some pretty-printing cases. The new method gdb.Value.lazy_string
2063 provides a simple way to create objects of this type.
2065 ** The fields returned by gdb.Type.fields now have an
2066 `is_base_class' attribute.
2068 ** The new method gdb.Type.range returns the range of an array type.
2070 ** The new method gdb.parse_and_eval can be used to parse and
2071 evaluate an expression.
2073 * New remote packets
2076 Define a trace state variable.
2079 Get the current value of a trace state variable.
2082 Set desired tracing behavior upon disconnection.
2085 Set the trace buffer to be linear or circular.
2088 Get data about the tracepoints currently in use.
2092 Process record now works correctly with hardware watchpoints.
2094 Multiple bug fixes have been made to the mips-irix port, making it
2095 much more reliable. In particular:
2096 - Debugging threaded applications is now possible again. Previously,
2097 GDB would hang while starting the program, or while waiting for
2098 the program to stop at a breakpoint.
2099 - Attaching to a running process no longer hangs.
2100 - An error occurring while loading a core file has been fixed.
2101 - Changing the value of the PC register now works again. This fixes
2102 problems observed when using the "jump" command, or when calling
2103 a function from GDB, or even when assigning a new value to $pc.
2104 - With the "finish" and "return" commands, the return value for functions
2105 returning a small array is now correctly printed.
2106 - It is now possible to break on shared library code which gets executed
2107 during a shared library init phase (code executed while executing
2108 their .init section). Previously, the breakpoint would have no effect.
2109 - GDB is now able to backtrace through the signal handler for
2110 non-threaded programs.
2112 PIE (Position Independent Executable) programs debugging is now supported.
2113 This includes debugging execution of PIC (Position Independent Code) shared
2114 libraries although for that, it should be possible to run such libraries as an
2117 *** Changes in GDB 7.0
2119 * GDB now has an interface for JIT compilation. Applications that
2120 dynamically generate code can create symbol files in memory and register
2121 them with GDB. For users, the feature should work transparently, and
2122 for JIT developers, the interface is documented in the GDB manual in the
2123 "JIT Compilation Interface" chapter.
2125 * Tracepoints may now be conditional. The syntax is as for
2126 breakpoints; either an "if" clause appended to the "trace" command,
2127 or the "condition" command is available. GDB sends the condition to
2128 the target for evaluation using the same bytecode format as is used
2129 for tracepoint actions.
2131 * The disassemble command now supports: an optional /r modifier, print the
2132 raw instructions in hex as well as in symbolic form, and an optional /m
2133 modifier to print mixed source+assembly.
2135 * Process record and replay
2137 In a architecture environment that supports ``process record and
2138 replay'', ``process record and replay'' target can record a log of
2139 the process execution, and replay it with both forward and reverse
2142 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2143 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2144 set execution-direction {forward|reverse}, for targets that support
2147 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2148 feature is available with a native GDB running on kernel version
2151 * GDB now has support for multi-byte and wide character sets on the
2152 target. Strings whose character type is wchar_t, char16_t, or
2153 char32_t are now correctly printed. GDB supports wide- and unicode-
2154 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2155 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2156 `printf'. This feature requires iconv to work properly; if your
2157 system does not have a working iconv, GDB can use GNU libiconv. See
2158 the installation instructions for more information.
2160 * GDB now supports automatic retrieval of shared library files from
2161 remote targets. To use this feature, specify a system root that begins
2162 with the `remote:' prefix, either via the `set sysroot' command or via
2163 the `--with-sysroot' configure-time option.
2165 * "info sharedlibrary" now takes an optional regex of libraries to show,
2166 and it now reports if a shared library has no debugging information.
2168 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2169 now complete on file names.
2171 * When completing in expressions, gdb will attempt to limit
2172 completions to allowable structure or union fields, where appropriate.
2173 For instance, consider:
2175 # struct example { int f1; double f2; };
2176 # struct example variable;
2179 If the user types TAB at the end of this command line, the available
2180 completions will be "f1" and "f2".
2182 * Inlined functions are now supported. They show up in backtraces, and
2183 the "step", "next", and "finish" commands handle them automatically.
2185 * GDB now supports the token-splicing (##) and stringification (#)
2186 operators when expanding macros. It also supports variable-arity
2189 * GDB now supports inspecting extra signal information, exported by
2190 the new $_siginfo convenience variable. The feature is currently
2191 implemented on linux ARM, i386 and amd64.
2193 * GDB can now display the VFP floating point registers and NEON vector
2194 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2195 can provide these registers (requires Linux 2.6.30 or later). Remote
2196 and simulator targets may also provide them.
2198 * New remote packets
2201 Search memory for a sequence of bytes.
2204 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2205 operation over reliable transport links. Use of this packet is
2206 controlled by the `set remote noack-packet' command.
2209 Kill the process with the specified process ID. Use this in preference
2210 to `k' when multiprocess protocol extensions are supported.
2213 Obtains additional operating system information
2217 Read or write additional signal information.
2219 * Removed remote protocol undocumented extension
2221 An undocumented extension to the remote protocol's `S' stop reply
2222 packet that permited the stub to pass a process id was removed.
2223 Remote servers should use the `T' stop reply packet instead.
2225 * GDB now supports multiple function calling conventions according to the
2226 DWARF-2 DW_AT_calling_convention function attribute.
2228 * The SH target utilizes the aforementioned change to distinguish between gcc
2229 and Renesas calling convention. It also adds the new CLI commands
2230 `set/show sh calling-convention'.
2232 * GDB can now read compressed debug sections, as produced by GNU gold
2233 with the --compress-debug-sections=zlib flag.
2235 * 64-bit core files are now supported on AIX.
2237 * Thread switching is now supported on Tru64.
2239 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2240 which will be allocated using malloc later in program execution.
2242 * The qXfer:libraries:read remote procotol packet now allows passing a
2243 list of section offsets.
2245 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2246 conditions handling signals delivered during attach or thread creation
2247 have also been fixed.
2249 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2250 From the user's standpoint, all unqualified instances of True and False
2251 are treated as the standard definitions, regardless of context.
2253 * GDB now parses C++ symbol and type names more flexibly. For
2256 template<typename T> class C { };
2259 GDB will now correctly handle all of:
2261 ptype C<char const *>
2262 ptype C<char const*>
2263 ptype C<const char *>
2264 ptype C<const char*>
2266 * New features in the GDB remote stub, gdbserver
2268 - The "--wrapper" command-line argument tells gdbserver to use a
2269 wrapper program to launch programs for debugging.
2271 - On PowerPC and S/390 targets, it is now possible to use a single
2272 gdbserver executable to debug both 32-bit and 64-bit programs.
2273 (This requires gdbserver itself to be built as a 64-bit executable.)
2275 - gdbserver uses the new noack protocol mode for TCP connections to
2276 reduce communications latency, if also supported and enabled in GDB.
2278 - Support for the sparc64-linux-gnu target is now included in
2281 - The amd64-linux build of gdbserver now supports debugging both
2282 32-bit and 64-bit programs.
2284 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2285 now support hardware watchpoints, and will use them automatically
2290 GDB now has support for scripting using Python. Whether this is
2291 available is determined at configure time.
2293 New GDB commands can now be written in Python.
2295 * Ada tasking support
2297 Ada tasks can now be inspected in GDB. The following commands have
2301 Print the list of Ada tasks.
2303 Print detailed information about task number N.
2305 Print the task number of the current task.
2307 Switch the context of debugging to task number N.
2309 * Support for user-defined prefixed commands. The "define" command can
2310 add new commands to existing prefixes, e.g. "target".
2312 * Multi-inferior, multi-process debugging.
2314 GDB now has generalized support for multi-inferior debugging. See
2315 "Debugging Multiple Inferiors" in the manual for more information.
2316 Although availability still depends on target support, the command
2317 set is more uniform now. The GNU/Linux specific multi-forks support
2318 has been migrated to this new framework. This implied some user
2319 visible changes; see "New commands" and also "Removed commands"
2322 * Target descriptions can now describe the target OS ABI. See the
2323 "Target Description Format" section in the user manual for more
2326 * Target descriptions can now describe "compatible" architectures
2327 to indicate that the target can execute applications for a different
2328 architecture in addition to those for the main target architecture.
2329 See the "Target Description Format" section in the user manual for
2332 * Multi-architecture debugging.
2334 GDB now includes general supports for debugging applications on
2335 hybrid systems that use more than one single processor architecture
2336 at the same time. Each such hybrid architecture still requires
2337 specific support to be added. The only hybrid architecture supported
2338 in this version of GDB is the Cell Broadband Engine.
2340 * GDB now supports integrated debugging of Cell/B.E. applications that
2341 use both the PPU and SPU architectures. To enable support for hybrid
2342 Cell/B.E. debugging, you need to configure GDB to support both the
2343 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2344 --enable-targets configure option.
2346 * Non-stop mode debugging.
2348 For some targets, GDB now supports an optional mode of operation in
2349 which you can examine stopped threads while other threads continue
2350 to execute freely. This is referred to as non-stop mode, with the
2351 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2352 section in the user manual for more information.
2354 To be able to support remote non-stop debugging, a remote stub needs
2355 to implement the non-stop mode remote protocol extensions, as
2356 described in the "Remote Non-Stop" section of the user manual. The
2357 GDB remote stub, gdbserver, has been adjusted to support these
2358 extensions on linux targets.
2360 * New commands (for set/show, see "New options" below)
2362 catch syscall [NAME(S) | NUMBER(S)]
2363 Catch system calls. Arguments, which should be names of system
2364 calls or their numbers, mean catch only those syscalls. Without
2365 arguments, every syscall will be caught. When the inferior issues
2366 any of the specified syscalls, GDB will stop and announce the system
2367 call, both when it is called and when its call returns. This
2368 feature is currently available with a native GDB running on the
2369 Linux Kernel, under the following architectures: x86, x86_64,
2370 PowerPC and PowerPC64.
2372 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2374 Search memory for a sequence of bytes.
2376 maint set python print-stack
2377 maint show python print-stack
2378 Show a stack trace when an error is encountered in a Python script.
2381 Invoke CODE by passing it to the Python interpreter.
2386 These allow macros to be defined, undefined, and listed
2390 Show operating system information about processes.
2393 List the inferiors currently under GDB's control.
2396 Switch focus to inferior number NUM.
2399 Detach from inferior number NUM.
2402 Kill inferior number NUM.
2406 set spu stop-on-load
2407 show spu stop-on-load
2408 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2410 set spu auto-flush-cache
2411 show spu auto-flush-cache
2412 Control whether to automatically flush the software-managed cache
2413 during Cell/B.E. debugging.
2415 set sh calling-convention
2416 show sh calling-convention
2417 Control the calling convention used when calling SH target functions.
2420 show debug timestamp
2421 Control display of timestamps with GDB debugging output.
2423 set disassemble-next-line
2424 show disassemble-next-line
2425 Control display of disassembled source lines or instructions when
2428 set remote noack-packet
2429 show remote noack-packet
2430 Set/show the use of remote protocol QStartNoAckMode packet. See above
2431 under "New remote packets."
2433 set remote query-attached-packet
2434 show remote query-attached-packet
2435 Control use of remote protocol `qAttached' (query-attached) packet.
2437 set remote read-siginfo-object
2438 show remote read-siginfo-object
2439 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2442 set remote write-siginfo-object
2443 show remote write-siginfo-object
2444 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2447 set remote reverse-continue
2448 show remote reverse-continue
2449 Control use of remote protocol 'bc' (reverse-continue) packet.
2451 set remote reverse-step
2452 show remote reverse-step
2453 Control use of remote protocol 'bs' (reverse-step) packet.
2455 set displaced-stepping
2456 show displaced-stepping
2457 Control displaced stepping mode. Displaced stepping is a way to
2458 single-step over breakpoints without removing them from the debuggee.
2459 Also known as "out-of-line single-stepping".
2462 show debug displaced
2463 Control display of debugging info for displaced stepping.
2465 maint set internal-error
2466 maint show internal-error
2467 Control what GDB does when an internal error is detected.
2469 maint set internal-warning
2470 maint show internal-warning
2471 Control what GDB does when an internal warning is detected.
2476 Use a wrapper program to launch programs for debugging.
2478 set multiple-symbols (all|ask|cancel)
2479 show multiple-symbols
2480 The value of this variable can be changed to adjust the debugger behavior
2481 when an expression or a breakpoint location contains an ambiguous symbol
2482 name (an overloaded function name, for instance).
2484 set breakpoint always-inserted
2485 show breakpoint always-inserted
2486 Keep breakpoints always inserted in the target, as opposed to inserting
2487 them when resuming the target, and removing them when the target stops.
2488 This option can improve debugger performance on slow remote targets.
2490 set arm fallback-mode (arm|thumb|auto)
2491 show arm fallback-mode
2492 set arm force-mode (arm|thumb|auto)
2494 These commands control how ARM GDB determines whether instructions
2495 are ARM or Thumb. The default for both settings is auto, which uses
2496 the current CPSR value for instructions without symbols; previous
2497 versions of GDB behaved as if "set arm fallback-mode arm".
2499 set disable-randomization
2500 show disable-randomization
2501 Standalone programs run with the virtual address space randomization enabled
2502 by default on some platforms. This option keeps the addresses stable across
2503 multiple debugging sessions.
2507 Control whether other threads are stopped or not when some thread hits
2512 Requests that asynchronous execution is enabled in the target, if available.
2513 In this case, it's possible to resume target in the background, and interact
2514 with GDB while the target is running. "show target-async" displays the
2515 current state of asynchronous execution of the target.
2517 set target-wide-charset
2518 show target-wide-charset
2519 The target-wide-charset is the name of the character set that GDB
2520 uses when printing characters whose type is wchar_t.
2522 set tcp auto-retry (on|off)
2524 set tcp connect-timeout
2525 show tcp connect-timeout
2526 These commands allow GDB to retry failed TCP connections to a remote stub
2527 with a specified timeout period; this is useful if the stub is launched
2528 in parallel with GDB but may not be ready to accept connections immediately.
2530 set libthread-db-search-path
2531 show libthread-db-search-path
2532 Control list of directories which GDB will search for appropriate
2535 set schedule-multiple (on|off)
2536 show schedule-multiple
2537 Allow GDB to resume all threads of all processes or only threads of
2538 the current process.
2542 Use more aggressive caching for accesses to the stack. This improves
2543 performance of remote debugging (particularly backtraces) without
2544 affecting correctness.
2546 set interactive-mode (on|off|auto)
2547 show interactive-mode
2548 Control whether GDB runs in interactive mode (on) or not (off).
2549 When in interactive mode, GDB waits for the user to answer all
2550 queries. Otherwise, GDB does not wait and assumes the default
2551 answer. When set to auto (the default), GDB determines which
2552 mode to use based on the stdin settings.
2557 For program forks, this is replaced by the new more generic `info
2558 inferiors' command. To list checkpoints, you can still use the
2559 `info checkpoints' command, which was an alias for the `info forks'
2563 Replaced by the new `inferior' command. To switch between
2564 checkpoints, you can still use the `restart' command, which was an
2565 alias for the `fork' command.
2568 This is removed, since some targets don't have a notion of
2569 processes. To switch between processes, you can still use the
2570 `inferior' command using GDB's own inferior number.
2573 For program forks, this is replaced by the new more generic `kill
2574 inferior' command. To delete a checkpoint, you can still use the
2575 `delete checkpoint' command, which was an alias for the `delete
2579 For program forks, this is replaced by the new more generic `detach
2580 inferior' command. To detach a checkpoint, you can still use the
2581 `detach checkpoint' command, which was an alias for the `detach
2584 * New native configurations
2586 x86/x86_64 Darwin i[34567]86-*-darwin*
2588 x86_64 MinGW x86_64-*-mingw*
2592 Lattice Mico32 lm32-*
2593 x86 DICOS i[34567]86-*-dicos*
2594 x86_64 DICOS x86_64-*-dicos*
2597 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2598 (mingw32ce) debugging.
2604 These commands were actually not implemented on any target.
2606 *** Changes in GDB 6.8
2608 * New native configurations
2610 NetBSD/hppa hppa*-*netbsd*
2611 Xtensa GNU/Linux xtensa*-*-linux*
2615 NetBSD/hppa hppa*-*-netbsd*
2616 Xtensa GNU/Lunux xtensa*-*-linux*
2618 * Change in command line behavior -- corefiles vs. process ids.
2620 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2621 attaching to process NUMBER fails, GDB no longer attempts to open a
2622 core file named NUMBER. Attaching to a program using the -c option
2623 is no longer supported. Instead, use the '-p' or '--pid' options.
2625 * GDB can now be built as a native debugger for debugging Windows x86
2626 (mingw32) Portable Executable (PE) programs.
2628 * Pending breakpoints no longer change their number when their address
2631 * GDB now supports breakpoints with multiple locations,
2632 including breakpoints on C++ constructors, inside C++ templates,
2633 and in inlined functions.
2635 * GDB's ability to debug optimized code has been improved. GDB more
2636 accurately identifies function bodies and lexical blocks that occupy
2637 more than one contiguous range of addresses.
2639 * Target descriptions can now describe registers for PowerPC.
2641 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2642 registers on PowerPC targets.
2644 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2645 targets even when the libthread_db library is not available.
2647 * The GDB remote stub, gdbserver, now supports the new file transfer
2648 commands (remote put, remote get, and remote delete).
2650 * The GDB remote stub, gdbserver, now supports run and attach in
2651 extended-remote mode.
2653 * hppa*64*-*-hpux11* target broken
2654 The debugger is unable to start a program and fails with the following
2655 error: "Error trying to get information about dynamic linker".
2656 The gdb-6.7 release is also affected.
2658 * GDB now supports the --enable-targets= configure option to allow
2659 building a single GDB executable that supports multiple remote
2660 target architectures.
2662 * GDB now supports debugging C and C++ programs which use the
2663 Decimal Floating Point extension. In addition, the PowerPC target
2664 now has a set of pseudo-registers to inspect decimal float values
2665 stored in two consecutive float registers.
2667 * The -break-insert MI command can optionally create pending
2670 * Improved support for debugging Ada
2671 Many improvements to the Ada language support have been made. These
2673 - Better support for Ada2005 interface types
2674 - Improved handling of arrays and slices in general
2675 - Better support for Taft-amendment types
2676 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2678 - Improved command completion in Ada
2681 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2686 set print frame-arguments (all|scalars|none)
2687 show print frame-arguments
2688 The value of this variable can be changed to control which argument
2689 values should be printed by the debugger when displaying a frame.
2694 Transfer files to and from a remote target, and delete remote files.
2701 Transfer files to and from a remote target, and delete remote files.
2703 * New remote packets
2710 Open, close, read, write, and delete files on the remote system.
2713 Attach to an existing process on the remote system, in extended-remote
2717 Run a new process on the remote system, in extended-remote mode.
2719 *** Changes in GDB 6.7
2721 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2722 bfd, libiberty and opcodes, as revealed by static analysis donated by
2723 Coverity, Inc. (http://scan.coverity.com).
2725 * When looking up multiply-defined global symbols, GDB will now prefer the
2726 symbol definition in the current shared library if it was built using the
2727 -Bsymbolic linker option.
2729 * When the Text User Interface (TUI) is not configured, GDB will now
2730 recognize the -tui command-line option and print a message that the TUI
2733 * The GDB remote stub, gdbserver, now has lower overhead for high
2734 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2736 * GDB for MIPS targets now autodetects whether a remote target provides
2737 32-bit or 64-bit register values.
2739 * Support for C++ member pointers has been improved.
2741 * GDB now understands XML target descriptions, which specify the
2742 target's overall architecture. GDB can read a description from
2743 a local file or over the remote serial protocol.
2745 * Vectors of single-byte data use a new integer type which is not
2746 automatically displayed as character or string data.
2748 * The /s format now works with the print command. It displays
2749 arrays of single-byte integers and pointers to single-byte integers
2752 * Target descriptions can now describe target-specific registers,
2753 for architectures which have implemented the support (currently
2754 only ARM, M68K, and MIPS).
2756 * GDB and the GDB remote stub, gdbserver, now support the XScale
2759 * The GDB remote stub, gdbserver, has been updated to support
2760 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2761 has been rewritten to use the standard GDB remote protocol.
2763 * GDB can now step into C++ functions which are called through thunks.
2765 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2767 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2768 layout. It also supports a TextSeg= and DataSeg= response when only
2769 segment base addresses (rather than offsets) are available.
2771 * The /i format now outputs any trailing branch delay slot instructions
2772 immediately following the last instruction within the count specified.
2774 * The GDB remote protocol "T" stop reply packet now supports a
2775 "library" response. Combined with the new "qXfer:libraries:read"
2776 packet, this response allows GDB to debug shared libraries on targets
2777 where the operating system manages the list of loaded libraries (e.g.
2778 Windows and SymbianOS).
2780 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2781 (DLLs) on Windows and Windows CE targets.
2783 * GDB now supports a faster verification that a .debug file matches its binary
2784 according to its build-id signature, if the signature is present.
2790 Enable or disable hardware flow control (RTS/CTS) on the serial port
2791 when debugging using remote targets.
2793 set mem inaccessible-by-default
2794 show mem inaccessible-by-default
2795 If the target supplies a memory map, for instance via the remote
2796 protocol's "qXfer:memory-map:read" packet, setting this variable
2797 prevents GDB from accessing memory outside the memory map. This
2798 is useful for targets with memory mapped registers or which react
2799 badly to accesses of unmapped address space.
2801 set breakpoint auto-hw
2802 show breakpoint auto-hw
2803 If the target supplies a memory map, for instance via the remote
2804 protocol's "qXfer:memory-map:read" packet, setting this variable
2805 lets GDB use hardware breakpoints automatically for memory regions
2806 where it can not use software breakpoints. This covers both the
2807 "break" command and internal breakpoints used for other commands
2808 including "next" and "finish".
2811 catch exception unhandled
2812 Stop the program execution when Ada exceptions are raised.
2815 Stop the program execution when an Ada assertion failed.
2819 Set an alternate system root for target files. This is a more
2820 general version of "set solib-absolute-prefix", which is now
2821 an alias to "set sysroot".
2824 Provide extended SPU facility status information. This set of
2825 commands is available only when debugging the Cell/B.E. SPU
2828 * New native configurations
2830 OpenBSD/sh sh*-*openbsd*
2833 unset tdesc filename
2835 Use the specified local file as an XML target description, and do
2836 not query the target for its built-in description.
2840 OpenBSD/sh sh*-*-openbsd*
2841 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2842 Toshiba Media Processor mep-elf
2844 * New remote packets
2847 Ignore the specified signals; pass them directly to the debugged program
2848 without stopping other threads or reporting them to GDB.
2850 qXfer:features:read:
2851 Read an XML target description from the target, which describes its
2856 Read or write contents of an spufs file on the target system. These
2857 packets are available only on the Cell/B.E. SPU architecture.
2859 qXfer:libraries:read:
2860 Report the loaded shared libraries. Combined with new "T" packet
2861 response, this packet allows GDB to debug shared libraries on
2862 targets where the operating system manages the list of loaded
2863 libraries (e.g. Windows and SymbianOS).
2867 Support for these obsolete configurations has been removed.
2875 i[34567]86-*-lynxos*
2876 i[34567]86-*-netware*
2877 i[34567]86-*-sco3.2v5*
2878 i[34567]86-*-sco3.2v4*
2880 i[34567]86-*-sysv4.2*
2883 i[34567]86-*-unixware2*
2884 i[34567]86-*-unixware*
2893 * Other removed features
2900 Various m68k-only ROM monitors.
2907 Various Renesas ROM monitors and debugging interfaces for SH and
2912 Support for a Macraigor serial interface to on-chip debugging.
2913 GDB does not directly support the newer parallel or USB
2918 A debug information format. The predecessor to DWARF 2 and
2919 DWARF 3, which are still supported.
2921 Support for the HP aCC compiler on HP-UX/PA-RISC
2923 SOM-encapsulated symbolic debugging information, automatic
2924 invocation of pxdb, and the aCC custom C++ ABI. This does not
2925 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2926 with aCC can still be debugged on an assembly level.
2928 MIPS ".pdr" sections
2930 A MIPS-specific format used to describe stack frame layout
2931 in debugging information.
2935 GDB could work with an older version of Guile to debug
2936 the interpreter and Scheme programs running in it.
2938 set mips stack-arg-size
2939 set mips saved-gpreg-size
2941 Use "set mips abi" to control parameter passing for MIPS.
2943 *** Changes in GDB 6.6
2948 Cell Broadband Engine SPU spu-elf
2950 * GDB can now be configured as a cross-debugger targeting native Windows
2951 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2952 running on a Windows system over TCP/IP to debug Windows programs.
2954 * The GDB remote stub, gdbserver, has been updated to support Windows and
2955 Cygwin debugging. Both single-threaded and multi-threaded programs are
2958 * The "set trust-readonly-sections" command works again. This command was
2959 broken in GDB 6.3, 6.4, and 6.5.
2961 * The "load" command now supports writing to flash memory, if the remote
2962 stub provides the required support.
2964 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2965 longer requires symbolic debug information (e.g. DWARF-2).
2970 unset substitute-path
2971 show substitute-path
2972 Manage a list of substitution rules that GDB uses to rewrite the name
2973 of the directories where the sources are located. This can be useful
2974 for instance when the sources were moved to a different location
2975 between compilation and debugging.
2979 Print each CLI command as it is executed. Each command is prefixed with
2980 a number of `+' symbols representing the nesting depth.
2981 The source command now has a `-v' option to enable the same feature.
2985 The ARM Demon monitor support (RDP protocol, "target rdp").
2987 Kernel Object Display, an embedded debugging feature which only worked with
2988 an obsolete version of Cisco IOS.
2990 The 'set download-write-size' and 'show download-write-size' commands.
2992 * New remote packets
2995 Tell a stub about GDB client features, and request remote target features.
2996 The first feature implemented is PacketSize, which allows the target to
2997 specify the size of packets it can handle - to minimize the number of
2998 packets required and improve performance when connected to a remote
3002 Fetch an OS auxilliary vector from the remote stub. This packet is a
3003 more efficient replacement for qPart:auxv:read.
3005 qXfer:memory-map:read:
3006 Fetch a memory map from the remote stub, including information about
3007 RAM, ROM, and flash memory devices.
3012 Erase and program a flash memory device.
3014 * Removed remote packets
3017 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3018 used it, and only gdbserver implemented it.
3020 *** Changes in GDB 6.5
3024 Renesas M32C/M16C m32c-elf
3026 Morpho Technologies ms1 ms1-elf
3030 init-if-undefined Initialize a convenience variable, but
3031 only if it doesn't already have a value.
3033 The following commands are presently only implemented for native GNU/Linux:
3035 checkpoint Save a snapshot of the program state.
3037 restart <n> Return the program state to a
3038 previously saved state.
3040 info checkpoints List currently saved checkpoints.
3042 delete-checkpoint <n> Delete a previously saved checkpoint.
3044 set|show detach-on-fork Tell gdb whether to detach from a newly
3045 forked process, or to keep debugging it.
3047 info forks List forks of the user program that
3048 are available to be debugged.
3050 fork <n> Switch to debugging one of several
3051 forks of the user program that are
3052 available to be debugged.
3054 delete-fork <n> Delete a fork from the list of forks
3055 that are available to be debugged (and
3056 kill the forked process).
3058 detach-fork <n> Delete a fork from the list of forks
3059 that are available to be debugged (and
3060 allow the process to continue).
3064 Morpho Technologies ms2 ms1-elf
3066 * Improved Windows host support
3068 GDB now builds as a cross debugger hosted on i686-mingw32, including
3069 native console support, and remote communications using either
3070 network sockets or serial ports.
3072 * Improved Modula-2 language support
3074 GDB can now print most types in the Modula-2 syntax. This includes:
3075 basic types, set types, record types, enumerated types, range types,
3076 pointer types and ARRAY types. Procedure var parameters are correctly
3077 printed and hexadecimal addresses and character constants are also
3078 written in the Modula-2 syntax. Best results can be obtained by using
3079 GNU Modula-2 together with the -gdwarf-2 command line option.
3083 The ARM rdi-share module.
3085 The Netware NLM debug server.
3087 *** Changes in GDB 6.4
3089 * New native configurations
3091 OpenBSD/arm arm*-*-openbsd*
3092 OpenBSD/mips64 mips64-*-openbsd*
3096 Morpho Technologies ms1 ms1-elf
3098 * New command line options
3100 --batch-silent As for --batch, but totally silent.
3101 --return-child-result The debugger will exist with the same value
3102 the child (debugged) program exited with.
3103 --eval-command COMMAND, -ex COMMAND
3104 Execute a single GDB CLI command. This may be
3105 specified multiple times and in conjunction
3106 with the --command (-x) option.
3108 * Deprecated commands removed
3110 The following commands, that were deprecated in 2000, have been
3114 set|show arm disassembly-flavor set|show arm disassembler
3115 othernames set arm disassembler
3116 set|show remotedebug set|show debug remote
3117 set|show archdebug set|show debug arch
3118 set|show eventdebug set|show debug event
3121 * New BSD user-level threads support
3123 It is now possible to debug programs using the user-level threads
3124 library on OpenBSD and FreeBSD. Currently supported (target)
3127 FreeBSD/amd64 x86_64-*-freebsd*
3128 FreeBSD/i386 i386-*-freebsd*
3129 OpenBSD/i386 i386-*-openbsd*
3131 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3132 are not yet supported.
3134 * New support for Matsushita MN10300 w/sim added
3135 (Work in progress). mn10300-elf.
3137 * REMOVED configurations and files
3139 VxWorks and the XDR protocol *-*-vxworks
3140 Motorola MCORE mcore-*-*
3141 National Semiconductor NS32000 ns32k-*-*
3143 * New "set print array-indexes" command
3145 After turning this setting "on", GDB prints the index of each element
3146 when displaying arrays. The default is "off" to preserve the previous
3149 * VAX floating point support
3151 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3153 * User-defined command support
3155 In addition to using $arg0..$arg9 for argument passing, it is now possible
3156 to use $argc to determine now many arguments have been passed. See the
3157 section on user-defined commands in the user manual for more information.
3159 *** Changes in GDB 6.3:
3161 * New command line option
3163 GDB now accepts -l followed by a number to set the timeout for remote
3166 * GDB works with GCC -feliminate-dwarf2-dups
3168 GDB now supports a more compact representation of DWARF-2 debug
3169 information using DW_FORM_ref_addr references. These are produced
3170 by GCC with the option -feliminate-dwarf2-dups and also by some
3171 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3172 to use -feliminate-dwarf2-dups.
3174 * Internationalization
3176 When supported by the host system, GDB will be built with
3177 internationalization (libintl). The task of marking up the sources is
3178 continued, we're looking forward to our first translation.
3182 Initial support for debugging programs compiled with the GNAT
3183 implementation of the Ada programming language has been integrated
3184 into GDB. In this release, support is limited to expression evaluation.
3186 * New native configurations
3188 GNU/Linux/m32r m32r-*-linux-gnu
3192 GDB's remote protocol now includes support for the 'p' packet. This
3193 packet is used to fetch individual registers from a remote inferior.
3195 * END-OF-LIFE registers[] compatibility module
3197 GDB's internal register infrastructure has been completely rewritten.
3198 The new infrastructure making possible the implementation of key new
3199 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3202 GDB 6.3 will be the last release to include the the registers[]
3203 compatibility module that allowed out-of-date configurations to
3204 continue to work. This change directly impacts the following
3214 powerpc bdm protocol
3216 Unless there is activity to revive these configurations, they will be
3217 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3219 * OBSOLETE configurations and files
3221 Configurations that have been declared obsolete in this release have
3222 been commented out. Unless there is activity to revive these
3223 configurations, the next release of GDB will have their sources
3224 permanently REMOVED.
3233 *** Changes in GDB 6.2.1:
3235 * MIPS `break main; run' gave an heuristic-fence-post warning
3237 When attempting to run even a simple program, a warning about
3238 heuristic-fence-post being hit would be reported. This problem has
3241 * MIPS IRIX 'long double' crashed GDB
3243 When examining a long double variable, GDB would get a segmentation
3244 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3245 IRIX long double values).
3249 A bug in the VAX stack code was causing problems with the "next"
3250 command. This problem has been fixed.
3252 *** Changes in GDB 6.2:
3254 * Fix for ``many threads''
3256 On GNU/Linux systems that use the NPTL threads library, a program
3257 rapidly creating and deleting threads would confuse GDB leading to the
3260 ptrace: No such process.
3261 thread_db_get_info: cannot get thread info: generic error
3263 This problem has been fixed.
3265 * "-async" and "-noasync" options removed.
3267 Support for the broken "-noasync" option has been removed (it caused
3270 * New ``start'' command.
3272 This command runs the program until the begining of the main procedure.
3274 * New BSD Kernel Data Access Library (libkvm) interface
3276 Using ``target kvm'' it is now possible to debug kernel core dumps and
3277 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3278 platforms. Currently supported (native-only) configurations are:
3280 FreeBSD/amd64 x86_64-*-freebsd*
3281 FreeBSD/i386 i?86-*-freebsd*
3282 NetBSD/i386 i?86-*-netbsd*
3283 NetBSD/m68k m68*-*-netbsd*
3284 NetBSD/sparc sparc-*-netbsd*
3285 OpenBSD/amd64 x86_64-*-openbsd*
3286 OpenBSD/i386 i?86-*-openbsd*
3287 OpenBSD/m68k m68*-openbsd*
3288 OpenBSD/sparc sparc-*-openbsd*
3290 * Signal trampoline code overhauled
3292 Many generic problems with GDB's signal handling code have been fixed.
3293 These include: backtraces through non-contiguous stacks; recognition
3294 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3295 call; backtrace through a signal trampoline; step into and out of
3296 signal handlers; and single-stepping in the signal trampoline.
3298 Please note that kernel bugs are a limiting factor here. These
3299 features have been shown to work on an s390 GNU/Linux system that
3300 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3302 * Cygwin support for DWARF 2 added.
3304 * New native configurations
3306 GNU/Linux/hppa hppa*-*-linux*
3307 OpenBSD/hppa hppa*-*-openbsd*
3308 OpenBSD/m68k m68*-*-openbsd*
3309 OpenBSD/m88k m88*-*-openbsd*
3310 OpenBSD/powerpc powerpc-*-openbsd*
3311 NetBSD/vax vax-*-netbsd*
3312 OpenBSD/vax vax-*-openbsd*
3314 * END-OF-LIFE frame compatibility module
3316 GDB's internal frame infrastructure has been completely rewritten.
3317 The new infrastructure making it possible to support key new features
3318 including DWARF 2 Call Frame Information. To aid in the task of
3319 migrating old configurations to this new infrastructure, a
3320 compatibility module, that allowed old configurations to continue to
3321 work, was also included.
3323 GDB 6.2 will be the last release to include this frame compatibility
3324 module. This change directly impacts the following configurations:
3334 Unless there is activity to revive these configurations, they will be
3335 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3337 * REMOVED configurations and files
3339 Sun 3, running SunOS 3 m68*-*-sunos3*
3340 Sun 3, running SunOS 4 m68*-*-sunos4*
3341 Sun 2, running SunOS 3 m68000-*-sunos3*
3342 Sun 2, running SunOS 4 m68000-*-sunos4*
3343 Motorola 680x0 running LynxOS m68*-*-lynxos*
3344 AT&T 3b1/Unix pc m68*-att-*
3345 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3346 decstation mips-dec-* mips-little-*
3347 riscos mips-*-riscos* mips-*-sysv*
3348 sonymips mips-sony-*
3349 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3351 *** Changes in GDB 6.1.1:
3353 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3355 The TUI (Text-mode User Interface) is now built as part of a default
3356 GDB configuration. It is enabled by either selecting the TUI with the
3357 command line option "-i=tui" or by running the separate "gdbtui"
3358 program. For more information on the TUI, see the manual "Debugging
3361 * Pending breakpoint support (also included in GDB 6.1)
3363 Support has been added to allow you to specify breakpoints in shared
3364 libraries that have not yet been loaded. If a breakpoint location
3365 cannot be found, and the "breakpoint pending" option is set to auto,
3366 GDB queries you if you wish to make the breakpoint pending on a future
3367 shared-library load. If and when GDB resolves the breakpoint symbol,
3368 the pending breakpoint is removed as one or more regular breakpoints
3371 Pending breakpoints are very useful for GCJ Java debugging.
3373 * Fixed ISO-C build problems
3375 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3376 non ISO-C code that stopped them being built using a more strict ISO-C
3377 compiler (e.g., IBM's C compiler).
3379 * Fixed build problem on IRIX 5
3381 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3382 wasn't able to compile compile on an IRIX 5 system.
3384 * Added execute permission to gdb/gdbserver/configure
3386 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3387 permission. This bug would cause configure to fail on a number of
3388 systems (Solaris, IRIX). Ref: server/519.
3390 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3392 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3393 has been updated to use constant array sizes.
3395 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3397 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3398 its generated DWARF Call Frame Info. This encoding was causing GDB to
3399 panic, that panic has been fixed. Ref: gdb/1628.
3401 * Fixed a problem when examining parameters in shared library code.
3403 When examining parameters in optimized shared library code generated
3404 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3405 not available''. GDB now correctly displays the variable's value.
3407 *** Changes in GDB 6.1:
3409 * Removed --with-mmalloc
3411 Support for the mmalloc memory manager has been removed, as it
3412 conflicted with the internal gdb byte cache.
3414 * Changes in AMD64 configurations
3416 The AMD64 target now includes the %cs and %ss registers. As a result
3417 the AMD64 remote protocol has changed; this affects the floating-point
3418 and SSE registers. If you rely on those registers for your debugging,
3419 you should upgrade gdbserver on the remote side.
3421 * Revised SPARC target
3423 The SPARC target has been completely revised, incorporating the
3424 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3425 support for LynxOS and SunOS 4 has been dropped. Calling functions
3426 from within GDB on operating systems with a non-executable stack
3427 (Solaris, OpenBSD) now works.
3431 GDB has a new C++ demangler which does a better job on the mangled
3432 names generated by current versions of g++. It also runs faster, so
3433 with this and other changes gdb should now start faster on large C++
3436 * DWARF 2 Location Expressions
3438 GDB support for location expressions has been extended to support function
3439 arguments and frame bases. Older versions of GDB could crash when they
3442 * C++ nested types and namespaces
3444 GDB's support for nested types and namespaces in C++ has been
3445 improved, especially if you use the DWARF 2 debugging format. (This
3446 is the default for recent versions of GCC on most platforms.)
3447 Specifically, if you have a class "Inner" defined within a class or
3448 namespace "Outer", then GDB realizes that the class's name is
3449 "Outer::Inner", not simply "Inner". This should greatly reduce the
3450 frequency of complaints about not finding RTTI symbols. In addition,
3451 if you are stopped at inside of a function defined within a namespace,
3452 GDB modifies its name lookup accordingly.
3454 * New native configurations
3456 NetBSD/amd64 x86_64-*-netbsd*
3457 OpenBSD/amd64 x86_64-*-openbsd*
3458 OpenBSD/alpha alpha*-*-openbsd*
3459 OpenBSD/sparc sparc-*-openbsd*
3460 OpenBSD/sparc64 sparc64-*-openbsd*
3462 * New debugging protocols
3464 M32R with SDI protocol m32r-*-elf*
3466 * "set prompt-escape-char" command deleted.
3468 The command "set prompt-escape-char" has been deleted. This command,
3469 and its very obscure effet on GDB's prompt, was never documented,
3470 tested, nor mentioned in the NEWS file.
3472 * OBSOLETE configurations and files
3474 Configurations that have been declared obsolete in this release have
3475 been commented out. Unless there is activity to revive these
3476 configurations, the next release of GDB will have their sources
3477 permanently REMOVED.
3479 Sun 3, running SunOS 3 m68*-*-sunos3*
3480 Sun 3, running SunOS 4 m68*-*-sunos4*
3481 Sun 2, running SunOS 3 m68000-*-sunos3*
3482 Sun 2, running SunOS 4 m68000-*-sunos4*
3483 Motorola 680x0 running LynxOS m68*-*-lynxos*
3484 AT&T 3b1/Unix pc m68*-att-*
3485 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3486 decstation mips-dec-* mips-little-*
3487 riscos mips-*-riscos* mips-*-sysv*
3488 sonymips mips-sony-*
3489 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3491 * REMOVED configurations and files
3493 SGI Irix-4.x mips-sgi-irix4 or iris4
3494 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3495 Z8000 simulator z8k-zilog-none or z8ksim
3496 Matsushita MN10200 w/simulator mn10200-*-*
3497 H8/500 simulator h8500-hitachi-hms or h8500hms
3498 HP/PA running BSD hppa*-*-bsd*
3499 HP/PA running OSF/1 hppa*-*-osf*
3500 HP/PA Pro target hppa*-*-pro*
3501 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3502 386BSD i[3456]86-*-bsd*
3503 Sequent family i[3456]86-sequent-sysv4*
3504 i[3456]86-sequent-sysv*
3505 i[3456]86-sequent-bsd*
3506 SPARC running LynxOS sparc-*-lynxos*
3507 SPARC running SunOS 4 sparc-*-sunos4*
3508 Tsqware Sparclet sparclet-*-*
3509 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3511 *** Changes in GDB 6.0:
3515 Support for debugging the Objective-C programming language has been
3516 integrated into GDB.
3518 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3520 DWARF 2's Call Frame Information makes available compiler generated
3521 information that more exactly describes the program's run-time stack.
3522 By using this information, GDB is able to provide more robust stack
3525 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3526 have been updated to use a new backtrace mechanism which includes
3527 DWARF 2 CFI support.
3531 GDB's remote protocol has been extended to include support for hosted
3532 file I/O (where the remote target uses GDB's file system). See GDB's
3533 remote protocol documentation for details.
3535 * All targets using the new architecture framework.
3537 All of GDB's targets have been updated to use the new internal
3538 architecture framework. The way is now open for future GDB releases
3539 to include cross-architecture native debugging support (i386 on amd64,
3542 * GNU/Linux's Thread Local Storage (TLS)
3544 GDB now includes support for for the GNU/Linux implementation of
3545 per-thread variables.
3547 * GNU/Linux's Native POSIX Thread Library (NPTL)
3549 GDB's thread code has been updated to work with either the new
3550 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3552 * Separate debug info.
3554 GDB, in conjunction with BINUTILS, now supports a mechanism for
3555 automatically loading debug information from a separate file. Instead
3556 of shipping full debug and non-debug versions of system libraries,
3557 system integrators can now instead ship just the stripped libraries
3558 and optional debug files.
3560 * DWARF 2 Location Expressions
3562 DWARF 2 Location Expressions allow the compiler to more completely
3563 describe the location of variables (even in optimized code) to the
3566 GDB now includes preliminary support for location expressions (support
3567 for DW_OP_piece is still missing).
3571 A number of long standing bugs that caused GDB to die while starting a
3572 Java application have been fixed. GDB's Java support is now
3573 considered "useable".
3575 * GNU/Linux support for fork, vfork, and exec.
3577 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3578 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3581 * GDB supports logging output to a file
3583 There are two new commands, "set logging" and "show logging", which can be
3584 used to capture GDB's output to a file.
3586 * The meaning of "detach" has changed for gdbserver
3588 The "detach" command will now resume the application, as documented. To
3589 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3592 * d10v, m68hc11 `regs' command deprecated
3594 The `info registers' command has been updated so that it displays the
3595 registers using a format identical to the old `regs' command.
3599 A new command, "maint set profile on/off", has been added. This command can
3600 be used to enable or disable profiling while running GDB, to profile a
3601 session or a set of commands. In addition there is a new configure switch,
3602 "--enable-profiling", which will cause GDB to be compiled with profiling
3603 data, for more informative profiling results.
3605 * Default MI syntax changed to "mi2".
3607 The default MI (machine interface) syntax, enabled by the command line
3608 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3609 "mi1", can be enabled by specifying the option "-i=mi1".
3611 Support for the original "mi0" syntax (included in GDB 5.0) has been
3614 Fix for gdb/192: removed extraneous space when displaying frame level.
3615 Fix for gdb/672: update changelist is now output in mi list format.
3616 Fix for gdb/702: a -var-assign that updates the value now shows up
3617 in a subsequent -var-update.
3619 * New native configurations.
3621 FreeBSD/amd64 x86_64-*-freebsd*
3623 * Multi-arched targets.
3625 HP/PA HPUX11 hppa*-*-hpux*
3626 Renesas M32R/D w/simulator m32r-*-elf*
3628 * OBSOLETE configurations and files
3630 Configurations that have been declared obsolete in this release have
3631 been commented out. Unless there is activity to revive these
3632 configurations, the next release of GDB will have their sources
3633 permanently REMOVED.
3635 Z8000 simulator z8k-zilog-none or z8ksim
3636 Matsushita MN10200 w/simulator mn10200-*-*
3637 H8/500 simulator h8500-hitachi-hms or h8500hms
3638 HP/PA running BSD hppa*-*-bsd*
3639 HP/PA running OSF/1 hppa*-*-osf*
3640 HP/PA Pro target hppa*-*-pro*
3641 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3642 Sequent family i[3456]86-sequent-sysv4*
3643 i[3456]86-sequent-sysv*
3644 i[3456]86-sequent-bsd*
3645 Tsqware Sparclet sparclet-*-*
3646 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3648 * REMOVED configurations and files
3651 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3652 IBM AIX PS/2 i[3456]86-*-aix
3653 i386 running Mach 3.0 i[3456]86-*-mach3*
3654 i386 running Mach i[3456]86-*-mach*
3655 i386 running OSF/1 i[3456]86-*osf1mk*
3656 HP/Apollo 68k Family m68*-apollo*-sysv*,
3658 m68*-hp-bsd*, m68*-hp-hpux*
3659 Argonaut Risc Chip (ARC) arc-*-*
3660 Mitsubishi D30V d30v-*-*
3661 Fujitsu FR30 fr30-*-elf*
3662 OS/9000 i[34]86-*-os9k
3663 I960 with MON960 i960-*-coff
3665 * MIPS $fp behavior changed
3667 The convenience variable $fp, for the MIPS, now consistently returns
3668 the address of the current frame's base. Previously, depending on the
3669 context, $fp could refer to either $sp or the current frame's base
3670 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3671 The GNU Source-Level Debugger''.
3673 *** Changes in GDB 5.3:
3675 * GNU/Linux shared library multi-threaded performance improved.
3677 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3678 `/proc', in preference to `ptrace' for memory reads. This may result
3679 in an improvement in the start-up time of multi-threaded, shared
3680 library applications when run under GDB. One GDB user writes: ``loads
3681 shared libs like mad''.
3683 * ``gdbserver'' now supports multi-threaded applications on some targets
3685 Support for debugging multi-threaded applications which use
3686 the GNU/Linux LinuxThreads package has been added for
3687 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3688 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3690 * GDB now supports C/C++ preprocessor macros.
3692 GDB now expands preprocessor macro invocations in C/C++ expressions,
3693 and provides various commands for showing macro definitions and how
3696 The new command `macro expand EXPRESSION' expands any macro
3697 invocations in expression, and shows the result.
3699 The new command `show macro MACRO-NAME' shows the definition of the
3700 macro named MACRO-NAME, and where it was defined.
3702 Most compilers don't include information about macros in the debugging
3703 information by default. In GCC 3.1, for example, you need to compile
3704 your program with the options `-gdwarf-2 -g3'. If the macro
3705 information is present in the executable, GDB will read it.
3707 * Multi-arched targets.
3709 DEC Alpha (partial) alpha*-*-*
3710 DEC VAX (partial) vax-*-*
3712 National Semiconductor NS32000 (partial) ns32k-*-*
3713 Motorola 68000 (partial) m68k-*-*
3714 Motorola MCORE mcore-*-*
3718 Fujitsu FRV architecture added by Red Hat frv*-*-*
3721 * New native configurations
3723 Alpha NetBSD alpha*-*-netbsd*
3724 SH NetBSD sh*-*-netbsdelf*
3725 MIPS NetBSD mips*-*-netbsd*
3726 UltraSPARC NetBSD sparc64-*-netbsd*
3728 * OBSOLETE configurations and files
3730 Configurations that have been declared obsolete in this release have
3731 been commented out. Unless there is activity to revive these
3732 configurations, the next release of GDB will have their sources
3733 permanently REMOVED.
3735 Mitsubishi D30V d30v-*-*
3736 OS/9000 i[34]86-*-os9k
3737 IBM AIX PS/2 i[3456]86-*-aix
3738 Fujitsu FR30 fr30-*-elf*
3739 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3740 Argonaut Risc Chip (ARC) arc-*-*
3741 i386 running Mach 3.0 i[3456]86-*-mach3*
3742 i386 running Mach i[3456]86-*-mach*
3743 i386 running OSF/1 i[3456]86-*osf1mk*
3744 HP/Apollo 68k Family m68*-apollo*-sysv*,
3746 m68*-hp-bsd*, m68*-hp-hpux*
3747 I960 with MON960 i960-*-coff
3749 * OBSOLETE languages
3751 CHILL, a Pascal like language used by telecommunications companies.
3753 * REMOVED configurations and files
3755 AMD 29k family via UDI a29k-amd-udi, udi29k
3756 A29K VxWorks a29k-*-vxworks
3757 AMD 29000 embedded, using EBMON a29k-none-none
3758 AMD 29000 embedded with COFF a29k-none-coff
3759 AMD 29000 embedded with a.out a29k-none-aout
3761 testsuite/gdb.hp/gdb.threads-hp/ directory
3763 * New command "set max-user-call-depth <nnn>"
3765 This command allows the user to limit the call depth of user-defined
3766 commands. The default is 1024.
3768 * Changes in FreeBSD/i386 native debugging.
3770 Support for the "generate-core-file" has been added.
3772 * New commands "dump", "append", and "restore".
3774 These commands allow data to be copied from target memory
3775 to a bfd-format or binary file (dump and append), and back
3776 from a file into memory (restore).
3778 * Improved "next/step" support on multi-processor Alpha Tru64.
3780 The previous single-step mechanism could cause unpredictable problems,
3781 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3782 of a software single-step mechanism prevents this.
3784 *** Changes in GDB 5.2.1:
3792 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3793 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3794 Fix, by Joel Brobecker imported from mainline.
3796 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3797 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3798 Fix, by Fred Fish, imported from mainline.
3800 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3801 Surprisingly enough, it works now.
3802 By Michal Ludvig, imported from mainline.
3804 i386 hardware watchpoint support:
3805 avoid misses on second run for some targets.
3806 By Pierre Muller, imported from mainline.
3808 *** Changes in GDB 5.2:
3810 * New command "set trust-readonly-sections on[off]".
3812 This command is a hint that tells gdb that read-only sections
3813 really are read-only (ie. that their contents will not change).
3814 In this mode, gdb will go to the object file rather than the
3815 target to read memory from read-only sections (such as ".text").
3816 This can be a significant performance improvement on some
3817 (notably embedded) targets.
3819 * New command "generate-core-file" (or "gcore").
3821 This new gdb command allows the user to drop a core file of the child
3822 process state at any time. So far it's been implemented only for
3823 GNU/Linux and Solaris, but should be relatively easily ported to other
3824 hosts. Argument is core file name (defaults to core.<pid>).
3826 * New command line option
3828 GDB now accepts --pid or -p followed by a process id.
3830 * Change in command line behavior -- corefiles vs. process ids.
3832 There is a subtle behavior in the way in which GDB handles
3833 command line arguments. The first non-flag argument is always
3834 a program to debug, but the second non-flag argument may either
3835 be a corefile or a process id. Previously, GDB would attempt to
3836 open the second argument as a corefile, and if that failed, would
3837 issue a superfluous error message and then attempt to attach it as
3838 a process. Now, if the second argument begins with a non-digit,
3839 it will be treated as a corefile. If it begins with a digit,
3840 GDB will attempt to attach it as a process, and if no such process
3841 is found, will then attempt to open it as a corefile.
3843 * Changes in ARM configurations.
3845 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3846 configuration is fully multi-arch.
3848 * New native configurations
3850 ARM NetBSD arm*-*-netbsd*
3851 x86 OpenBSD i[3456]86-*-openbsd*
3852 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3853 Sparc64 running FreeBSD sparc64-*-freebsd*
3857 Sanyo XStormy16 xstormy16-elf
3859 * OBSOLETE configurations and files
3861 Configurations that have been declared obsolete in this release have
3862 been commented out. Unless there is activity to revive these
3863 configurations, the next release of GDB will have their sources
3864 permanently REMOVED.
3866 AMD 29k family via UDI a29k-amd-udi, udi29k
3867 A29K VxWorks a29k-*-vxworks
3868 AMD 29000 embedded, using EBMON a29k-none-none
3869 AMD 29000 embedded with COFF a29k-none-coff
3870 AMD 29000 embedded with a.out a29k-none-aout
3872 testsuite/gdb.hp/gdb.threads-hp/ directory
3874 * REMOVED configurations and files
3876 TI TMS320C80 tic80-*-*
3878 PowerPC Solaris powerpcle-*-solaris*
3879 PowerPC Windows NT powerpcle-*-cygwin32
3880 PowerPC Netware powerpc-*-netware*
3881 Harris/CXUX m88k m88*-harris-cxux*
3882 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3883 ns32k-utek-sysv* ns32k-utek-*
3884 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3885 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3886 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3887 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3888 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3890 * Changes to command line processing
3892 The new `--args' feature can be used to specify command-line arguments
3893 for the inferior from gdb's command line.
3895 * Changes to key bindings
3897 There is a new `operate-and-get-next' function bound to `C-o'.
3899 *** Changes in GDB 5.1.1
3901 Fix compile problem on DJGPP.
3903 Fix a problem with floating-point registers on the i386 being
3906 Fix to stop GDB crashing on .debug_str debug info.
3908 Numerous documentation fixes.
3910 Numerous testsuite fixes.
3912 *** Changes in GDB 5.1:
3914 * New native configurations
3916 Alpha FreeBSD alpha*-*-freebsd*
3917 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3918 MIPS GNU/Linux mips*-*-linux*
3919 MIPS SGI Irix 6.x mips*-sgi-irix6*
3920 ia64 AIX ia64-*-aix*
3921 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3925 Motorola 68HC11 and 68HC12 m68hc11-elf
3927 UltraSparc running GNU/Linux sparc64-*-linux*
3929 * OBSOLETE configurations and files
3931 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3932 Harris/CXUX m88k m88*-harris-cxux*
3933 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3934 ns32k-utek-sysv* ns32k-utek-*
3935 TI TMS320C80 tic80-*-*
3937 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3938 PowerPC Solaris powerpcle-*-solaris*
3939 PowerPC Windows NT powerpcle-*-cygwin32
3940 PowerPC Netware powerpc-*-netware*
3941 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3942 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3943 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3944 Apple Macintosh (MPW) host N/A
3946 stuff.c (Program to stuff files into a specially prepared space in kdb)
3947 kdb-start.c (Main loop for the standalone kernel debugger)
3949 Configurations that have been declared obsolete in this release have
3950 been commented out. Unless there is activity to revive these
3951 configurations, the next release of GDB will have their sources
3952 permanently REMOVED.
3954 * REMOVED configurations and files
3956 Altos 3068 m68*-altos-*
3957 Convex c1-*-*, c2-*-*
3959 ARM RISCix arm-*-* (as host)
3963 * GDB has been converted to ISO C.
3965 GDB's source code has been converted to ISO C. In particular, the
3966 sources are fully protoized, and rely on standard headers being
3971 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3973 * The MI enabled by default.
3975 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3976 revised and enabled by default. Packages which use GDB as a debugging
3977 engine behind a UI or another front end are encouraged to switch to
3978 using the GDB/MI interface, instead of the old annotations interface
3979 which is now deprecated.
3981 * Support for debugging Pascal programs.
3983 GDB now includes support for debugging Pascal programs. The following
3984 main features are supported:
3986 - Pascal-specific data types such as sets;
3988 - automatic recognition of Pascal sources based on file-name
3991 - Pascal-style display of data types, variables, and functions;
3993 - a Pascal expression parser.
3995 However, some important features are not yet supported.
3997 - Pascal string operations are not supported at all;
3999 - there are some problems with boolean types;
4001 - Pascal type hexadecimal constants are not supported
4002 because they conflict with the internal variables format;
4004 - support for Pascal objects and classes is not full yet;
4006 - unlike Pascal, GDB is case-sensitive for symbol names.
4008 * Changes in completion.
4010 Commands such as `shell', `run' and `set args', which pass arguments
4011 to inferior programs, now complete on file names, similar to what
4012 users expect at the shell prompt.
4014 Commands which accept locations, such as `disassemble', `print',
4015 `breakpoint', `until', etc. now complete on filenames as well as
4016 program symbols. Thus, if you type "break foob TAB", and the source
4017 files linked into the programs include `foobar.c', that file name will
4018 be one of the candidates for completion. However, file names are not
4019 considered for completion after you typed a colon that delimits a file
4020 name from a name of a function in that file, as in "break foo.c:bar".
4022 `set demangle-style' completes on available demangling styles.
4024 * New platform-independent commands:
4026 It is now possible to define a post-hook for a command as well as a
4027 hook that runs before the command. For more details, see the
4028 documentation of `hookpost' in the GDB manual.
4030 * Changes in GNU/Linux native debugging.
4032 Support for debugging multi-threaded programs has been completely
4033 revised for all platforms except m68k and sparc. You can now debug as
4034 many threads as your system allows you to have.
4036 Attach/detach is supported for multi-threaded programs.
4038 Support for SSE registers was added for x86. This doesn't work for
4039 multi-threaded programs though.
4041 * Changes in MIPS configurations.
4043 Multi-arch support is enabled for all MIPS configurations.
4045 GDB can now be built as native debugger on SGI Irix 6.x systems for
4046 debugging n32 executables. (Debugging 64-bit executables is not yet
4049 * Unified support for hardware watchpoints in all x86 configurations.
4051 Most (if not all) native x86 configurations support hardware-assisted
4052 breakpoints and watchpoints in a unified manner. This support
4053 implements debug register sharing between watchpoints, which allows to
4054 put a virtually infinite number of watchpoints on the same address,
4055 and also supports watching regions up to 16 bytes with several debug
4058 The new maintenance command `maintenance show-debug-regs' toggles
4059 debugging print-outs in functions that insert, remove, and test
4060 watchpoints and hardware breakpoints.
4062 * Changes in the DJGPP native configuration.
4064 New command ``info dos sysinfo'' displays assorted information about
4065 the CPU, OS, memory, and DPMI server.
4067 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4068 display information about segment descriptors stored in GDT, LDT, and
4071 New commands ``info dos pde'' and ``info dos pte'' display entries
4072 from Page Directory and Page Tables (for now works with CWSDPMI only).
4073 New command ``info dos address-pte'' displays the Page Table entry for
4074 a given linear address.
4076 GDB can now pass command lines longer than 126 characters to the
4077 program being debugged (requires an update to the libdbg.a library
4078 which is part of the DJGPP development kit).
4080 DWARF2 debug info is now supported.
4082 It is now possible to `step' and `next' through calls to `longjmp'.
4084 * Changes in documentation.
4086 All GDB documentation was converted to GFDL, the GNU Free
4087 Documentation License.
4089 Tracepoints-related commands are now fully documented in the GDB
4092 TUI, the Text-mode User Interface, is now documented in the manual.
4094 Tracepoints-related commands are now fully documented in the GDB
4097 The "GDB Internals" manual now has an index. It also includes
4098 documentation of `ui_out' functions, GDB coding standards, x86
4099 hardware watchpoints, and memory region attributes.
4101 * GDB's version number moved to ``version.in''
4103 The Makefile variable VERSION has been replaced by the file
4104 ``version.in''. People creating GDB distributions should update the
4105 contents of this file.
4109 GUD support is now a standard part of the EMACS distribution.
4111 *** Changes in GDB 5.0:
4113 * Improved support for debugging FP programs on x86 targets
4115 Unified and much-improved support for debugging floating-point
4116 programs on all x86 targets. In particular, ``info float'' now
4117 displays the FP registers in the same format on all x86 targets, with
4118 greater level of detail.
4120 * Improvements and bugfixes in hardware-assisted watchpoints
4122 It is now possible to watch array elements, struct members, and
4123 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4124 on x86 targets no longer erroneously trigger when the address is
4127 * Improvements in the native DJGPP version of GDB
4129 The distribution now includes all the scripts and auxiliary files
4130 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4131 machines ``out of the box''.
4133 The DJGPP version can now debug programs that use signals. It is
4134 possible to catch signals that happened in the debuggee, deliver
4135 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4136 would kill the program being debugged.) Programs that hook hardware
4137 interrupts (keyboard, timer, etc.) can also be debugged.
4139 It is now possible to debug DJGPP programs that redirect their
4140 standard handles or switch them to raw (as opposed to cooked) mode, or
4141 even close them. The command ``run < foo > bar'' works as expected,
4142 and ``info terminal'' reports useful information about the debuggee's
4143 terminal, including raw/cooked mode, redirection, etc.
4145 The DJGPP version now uses termios functions for console I/O, which
4146 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4149 DOS-style file names with drive letters are now fully supported by
4152 It is now possible to debug DJGPP programs that switch their working
4153 directory. It is also possible to rerun the debuggee any number of
4154 times without restarting GDB; thus, you can use the same setup,
4155 breakpoints, etc. for many debugging sessions.
4157 * New native configurations
4159 ARM GNU/Linux arm*-*-linux*
4160 PowerPC GNU/Linux powerpc-*-linux*
4164 Motorola MCore mcore-*-*
4165 x86 VxWorks i[3456]86-*-vxworks*
4166 PowerPC VxWorks powerpc-*-vxworks*
4167 TI TMS320C80 tic80-*-*
4169 * OBSOLETE configurations
4171 Altos 3068 m68*-altos-*
4172 Convex c1-*-*, c2-*-*
4174 ARM RISCix arm-*-* (as host)
4177 Configurations that have been declared obsolete will be commented out,
4178 but the code will be left in place. If there is no activity to revive
4179 these configurations before the next release of GDB, the sources will
4180 be permanently REMOVED.
4182 * Gould support removed
4184 Support for the Gould PowerNode and NP1 has been removed.
4186 * New features for SVR4
4188 On SVR4 native platforms (such as Solaris), if you attach to a process
4189 without first loading a symbol file, GDB will now attempt to locate and
4190 load symbols from the running process's executable file.
4192 * Many C++ enhancements
4194 C++ support has been greatly improved. Overload resolution now works properly
4195 in almost all cases. RTTI support is on the way.
4197 * Remote targets can connect to a sub-program
4199 A popen(3) style serial-device has been added. This device starts a
4200 sub-process (such as a stand-alone simulator) and then communicates
4201 with that. The sub-program to run is specified using the syntax
4202 ``|<program> <args>'' vis:
4204 (gdb) set remotedebug 1
4205 (gdb) target extended-remote |mn10300-elf-sim program-args
4207 * MIPS 64 remote protocol
4209 A long standing bug in the mips64 remote protocol where by GDB
4210 expected certain 32 bit registers (ex SR) to be transfered as 32
4211 instead of 64 bits has been fixed.
4213 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4214 added to provide backward compatibility with older versions of GDB.
4216 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4218 The command ``set remotebinarydownload'' command has been replaced by
4219 ``set remote X-packet''. Other commands in ``set remote'' family
4220 include ``set remote P-packet''.
4222 * Breakpoint commands accept ranges.
4224 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4225 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4226 ``tracepoint passcount'' also accepts a range of tracepoints.
4228 * ``apropos'' command added.
4230 The ``apropos'' command searches through command names and
4231 documentation strings, printing out matches, making it much easier to
4232 try to find a command that does what you are looking for.
4236 A new machine oriented interface (MI) has been added to GDB. This
4237 interface is designed for debug environments running GDB as a separate
4238 process. This is part of the long term libGDB project. See the
4239 "GDB/MI" chapter of the GDB manual for further information. It can be
4240 enabled by configuring with:
4242 .../configure --enable-gdbmi
4244 *** Changes in GDB-4.18:
4246 * New native configurations
4248 HP-UX 10.20 hppa*-*-hpux10.20
4249 HP-UX 11.x hppa*-*-hpux11.0*
4250 M68K GNU/Linux m68*-*-linux*
4254 Fujitsu FR30 fr30-*-elf*
4255 Intel StrongARM strongarm-*-*
4256 Mitsubishi D30V d30v-*-*
4258 * OBSOLETE configurations
4260 Gould PowerNode, NP1 np1-*-*, pn-*-*
4262 Configurations that have been declared obsolete will be commented out,
4263 but the code will be left in place. If there is no activity to revive
4264 these configurations before the next release of GDB, the sources will
4265 be permanently REMOVED.
4269 As a compatibility experiment, GDB's source files buildsym.h and
4270 buildsym.c have been converted to pure standard C, no longer
4271 containing any K&R compatibility code. We believe that all systems in
4272 use today either come with a standard C compiler, or have a GCC port
4273 available. If this is not true, please report the affected
4275 information about getting a standard C compiler if you don't have one
4280 GDB now uses readline 2.2.
4282 * set extension-language
4284 You can now control the mapping between filename extensions and source
4285 languages by using the `set extension-language' command. For instance,
4286 you can ask GDB to treat .c files as C++ by saying
4287 set extension-language .c c++
4288 The command `info extensions' lists all of the recognized extensions
4289 and their associated languages.
4291 * Setting processor type for PowerPC and RS/6000
4293 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4294 you can use the `set processor' command to specify what variant of the
4295 PowerPC family you are debugging. The command
4299 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4300 following PowerPC and RS6000 variants:
4302 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4303 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4305 403GC IBM PowerPC 403GC
4306 505 Motorola PowerPC 505
4307 860 Motorola PowerPC 860 or 850
4308 601 Motorola PowerPC 601
4309 602 Motorola PowerPC 602
4310 603 Motorola/IBM PowerPC 603 or 603e
4311 604 Motorola PowerPC 604 or 604e
4312 750 Motorola/IBM PowerPC 750 or 750
4314 At the moment, this command just tells GDB what to name the
4315 special-purpose processor registers. Since almost all the affected
4316 registers are inaccessible to user-level programs, this command is
4317 only useful for remote debugging in its present form.
4321 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4322 more extensive support for HP-UX. Added features include shared
4323 library support, kernel threads and hardware watchpoints for 11.00,
4324 support for HP's ANSI C and C++ compilers, and a compatibility mode
4325 for xdb and dbx commands.
4329 HP's donation includes the new concept of catchpoints, which is a
4330 generalization of the old catch command. On HP-UX, it is now possible
4331 to catch exec, fork, and vfork, as well as library loading.
4333 This means that the existing catch command has changed; its first
4334 argument now specifies the type of catch to be set up. See the
4335 output of "help catch" for a list of catchpoint types.
4337 * Debugging across forks
4339 On HP-UX, you can choose which process to debug when a fork() happens
4344 HP has donated a curses-based terminal user interface (TUI). To get
4345 it, build with --enable-tui. Although this can be enabled for any
4346 configuration, at present it only works for native HP debugging.
4348 * GDB remote protocol additions
4350 A new protocol packet 'X' that writes binary data is now available.
4351 Default behavior is to try 'X', then drop back to 'M' if the stub
4352 fails to respond. The settable variable `remotebinarydownload'
4353 allows explicit control over the use of 'X'.
4355 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4356 full 64-bit address. The command
4358 set remoteaddresssize 32
4360 can be used to revert to the old behaviour. For existing remote stubs
4361 the change should not be noticed, as the additional address information
4364 In order to assist in debugging stubs, you may use the maintenance
4365 command `packet' to send any text string to the stub. For instance,
4367 maint packet heythere
4369 sends the packet "$heythere#<checksum>". Note that it is very easy to
4370 disrupt a debugging session by sending the wrong packet at the wrong
4373 The compare-sections command allows you to compare section data on the
4374 target to what is in the executable file without uploading or
4375 downloading, by comparing CRC checksums.
4377 * Tracing can collect general expressions
4379 You may now collect general expressions at tracepoints. This requires
4380 further additions to the target-side stub; see tracepoint.c and
4381 doc/agentexpr.texi for further details.
4383 * mask-address variable for Mips
4385 For Mips targets, you may control the zeroing of the upper 32 bits of
4386 a 64-bit address by entering `set mask-address on'. This is mainly
4387 of interest to users of embedded R4xxx and R5xxx processors.
4389 * Higher serial baud rates
4391 GDB's serial code now allows you to specify baud rates 57600, 115200,
4392 230400, and 460800 baud. (Note that your host system may not be able
4393 to achieve all of these rates.)
4397 The i960 configuration now includes an initial implementation of a
4398 builtin simulator, contributed by Jim Wilson.
4401 *** Changes in GDB-4.17:
4403 * New native configurations
4405 Alpha GNU/Linux alpha*-*-linux*
4406 Unixware 2.x i[3456]86-unixware2*
4407 Irix 6.x mips*-sgi-irix6*
4408 PowerPC GNU/Linux powerpc-*-linux*
4409 PowerPC Solaris powerpcle-*-solaris*
4410 Sparc GNU/Linux sparc-*-linux*
4411 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4415 Argonaut Risc Chip (ARC) arc-*-*
4416 Hitachi H8/300S h8300*-*-*
4417 Matsushita MN10200 w/simulator mn10200-*-*
4418 Matsushita MN10300 w/simulator mn10300-*-*
4419 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4420 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4421 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4422 Mitsubishi D10V w/simulator d10v-*-*
4423 Mitsubishi M32R/D w/simulator m32r-*-elf*
4424 Tsqware Sparclet sparclet-*-*
4425 NEC V850 w/simulator v850-*-*
4427 * New debugging protocols
4429 ARM with RDI protocol arm*-*-*
4430 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4431 DDB and LSI variants of PMON protocol mips*-*-*
4432 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4433 PowerPC with SDS protocol powerpc{,le}-*-eabi
4434 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4438 All configurations can now understand and use the DWARF 2 debugging
4439 format. The choice is automatic, if the symbol file contains DWARF 2
4444 GDB now includes basic Java language support. This support is
4445 only useful with Java compilers that produce native machine code.
4447 * solib-absolute-prefix and solib-search-path
4449 For SunOS and SVR4 shared libraries, you may now set the prefix for
4450 loading absolute shared library symbol files, and the search path for
4451 locating non-absolute shared library symbol files.
4453 * Live range splitting
4455 GDB can now effectively debug code for which GCC has performed live
4456 range splitting as part of its optimization. See gdb/doc/LRS for
4457 more details on the expected format of the stabs information.
4461 GDB's support for the GNU Hurd, including thread debugging, has been
4462 updated to work with current versions of the Hurd.
4466 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4467 instruction set. ARM GDB automatically detects when Thumb
4468 instructions are in use, and adjusts disassembly and backtracing
4473 GDB's MIPS target configurations now handle the MIP16 16-bit
4478 GDB now includes support for overlays; if an executable has been
4479 linked such that multiple sections are based at the same address, GDB
4480 will decide which section to use for symbolic info. You can choose to
4481 control the decision manually, using overlay commands, or implement
4482 additional target-side support and use "overlay load-target" to bring
4483 in the overlay mapping. Do "help overlay" for more detail.
4487 The command "info symbol <address>" displays information about
4488 the symbol at the specified address.
4492 The standard remote protocol now includes an extension that allows
4493 asynchronous collection and display of trace data. This requires
4494 extensive support in the target-side debugging stub. Tracing mode
4495 includes a new interaction mode in GDB and new commands: see the
4496 file tracepoint.c for more details.
4500 Configurations for embedded MIPS now include a simulator contributed
4501 by Cygnus Solutions. The simulator supports the instruction sets
4502 of most MIPS variants.
4506 Sparc configurations may now include the ERC32 simulator contributed
4507 by the European Space Agency. The simulator is not built into
4508 Sparc targets by default; configure with --enable-sim to include it.
4512 For target configurations that may include multiple variants of a
4513 basic architecture (such as MIPS and SH), you may now set the
4514 architecture explicitly. "set arch" sets, "info arch" lists
4515 the possible architectures.
4517 *** Changes in GDB-4.16:
4519 * New native configurations
4521 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4522 M68K NetBSD m68k-*-netbsd*
4523 PowerPC AIX 4.x powerpc-*-aix*
4524 PowerPC MacOS powerpc-*-macos*
4525 PowerPC Windows NT powerpcle-*-cygwin32
4526 RS/6000 AIX 4.x rs6000-*-aix4*
4530 ARM with RDP protocol arm-*-*
4531 I960 with MON960 i960-*-coff
4532 MIPS VxWorks mips*-*-vxworks*
4533 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4534 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4536 Matra Sparclet sparclet-*-*
4540 The powerpc-eabi configuration now includes the PSIM simulator,
4541 contributed by Andrew Cagney, with assistance from Mike Meissner.
4542 PSIM is a very elaborate model of the PowerPC, including not only
4543 basic instruction set execution, but also details of execution unit
4544 performance and I/O hardware. See sim/ppc/README for more details.
4548 GDB now works with Solaris 2.5.
4550 * Windows 95/NT native
4552 GDB will now work as a native debugger on Windows 95 and Windows NT.
4553 To build it from source, you must use the "gnu-win32" environment,
4554 which uses a DLL to emulate enough of Unix to run the GNU tools.
4555 Further information, binaries, and sources are available at
4556 ftp.cygnus.com, under pub/gnu-win32.
4558 * dont-repeat command
4560 If a user-defined command includes the command `dont-repeat', then the
4561 command will not be repeated if the user just types return. This is
4562 useful if the command is time-consuming to run, so that accidental
4563 extra keystrokes don't run the same command many times.
4565 * Send break instead of ^C
4567 The standard remote protocol now includes an option to send a break
4568 rather than a ^C to the target in order to interrupt it. By default,
4569 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4571 * Remote protocol timeout
4573 The standard remote protocol includes a new variable `remotetimeout'
4574 that allows you to set the number of seconds before GDB gives up trying
4575 to read from the target. The default value is 2.
4577 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4579 By default GDB will automatically keep track of objects as they are
4580 loaded and unloaded by the dynamic linker. By using the command `set
4581 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4582 when shared library events occur, thus allowing you to set breakpoints
4583 in shared libraries which are explicitly loaded by the inferior.
4585 Note this feature does not work on hpux8. On hpux9 you must link
4586 /usr/lib/end.o into your program. This feature should work
4587 automatically on hpux10.
4589 * Irix 5.x hardware watchpoint support
4591 Irix 5 configurations now support the use of hardware watchpoints.
4593 * Mips protocol "SYN garbage limit"
4595 When debugging a Mips target using the `target mips' protocol, you
4596 may set the number of characters that GDB will ignore by setting
4597 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4598 every character. The default value is 1050.
4600 * Recording and replaying remote debug sessions
4602 If you set `remotelogfile' to the name of a file, gdb will write to it
4603 a recording of a remote debug session. This recording may then be
4604 replayed back to gdb using "gdbreplay". See gdbserver/README for
4605 details. This is useful when you have a problem with GDB while doing
4606 remote debugging; you can make a recording of the session and send it
4607 to someone else, who can then recreate the problem.
4609 * Speedups for remote debugging
4611 GDB includes speedups for downloading and stepping MIPS systems using
4612 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4613 and more efficient S-record downloading.
4615 * Memory use reductions and statistics collection
4617 GDB now uses less memory and reports statistics about memory usage.
4618 Try the `maint print statistics' command, for example.
4620 *** Changes in GDB-4.15:
4622 * Psymtabs for XCOFF
4624 The symbol reader for AIX GDB now uses partial symbol tables. This
4625 can greatly improve startup time, especially for large executables.
4627 * Remote targets use caching
4629 Remote targets now use a data cache to speed up communication with the
4630 remote side. The data cache could lead to incorrect results because
4631 it doesn't know about volatile variables, thus making it impossible to
4632 debug targets which use memory mapped I/O devices. `set remotecache
4633 off' turns the the data cache off.
4635 * Remote targets may have threads
4637 The standard remote protocol now includes support for multiple threads
4638 in the target system, using new protocol commands 'H' and 'T'. See
4639 gdb/remote.c for details.
4643 If GDB is configured with `--enable-netrom', then it will include
4644 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4645 acts as though it is a bank of ROM on the target board, but you can
4646 write into it over the network. GDB's support consists only of
4647 support for fast loading into the emulated ROM; to debug, you must use
4648 another protocol, such as standard remote protocol. The usual
4649 sequence is something like
4651 target nrom <netrom-hostname>
4653 target remote <netrom-hostname>:1235
4657 GDB now includes support for the Apple Macintosh, as a host only. It
4658 may be run as either an MPW tool or as a standalone application, and
4659 it can debug through the serial port. All the usual GDB commands are
4660 available, but to the target command, you must supply "serial" as the
4661 device type instead of "/dev/ttyXX". See mpw-README in the main
4662 directory for more information on how to build. The MPW configuration
4663 scripts */mpw-config.in support only a few targets, and only the
4664 mips-idt-ecoff target has been tested.
4668 GDB configuration now uses autoconf. This is not user-visible,
4669 but does simplify configuration and building.
4673 GDB now supports hpux10.
4675 *** Changes in GDB-4.14:
4677 * New native configurations
4679 x86 FreeBSD i[345]86-*-freebsd
4680 x86 NetBSD i[345]86-*-netbsd
4681 NS32k NetBSD ns32k-*-netbsd
4682 Sparc NetBSD sparc-*-netbsd
4686 A29K VxWorks a29k-*-vxworks
4687 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4688 CPU32 EST-300 emulator m68*-*-est*
4689 PowerPC ELF powerpc-*-elf
4692 * Alpha OSF/1 support for procfs
4694 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4695 possible to attach to running processes. As the mounting of the /proc
4696 filesystem is optional on the Alpha, GDB automatically determines
4697 the availability of /proc during startup. This can lead to problems
4698 if /proc is unmounted after GDB has been started.
4700 * Arguments to user-defined commands
4702 User commands may accept up to 10 arguments separated by whitespace.
4703 Arguments are accessed within the user command via $arg0..$arg9. A
4706 print $arg0 + $arg1 + $arg2
4708 To execute the command use:
4711 Defines the command "adder" which prints the sum of its three arguments.
4712 Note the arguments are text substitutions, so they may reference variables,
4713 use complex expressions, or even perform inferior function calls.
4715 * New `if' and `while' commands
4717 This makes it possible to write more sophisticated user-defined
4718 commands. Both commands take a single argument, which is the
4719 expression to evaluate, and must be followed by the commands to
4720 execute, one per line, if the expression is nonzero, the list being
4721 terminated by the word `end'. The `if' command list may include an
4722 `else' word, which causes the following commands to be executed only
4723 if the expression is zero.
4725 * Fortran source language mode
4727 GDB now includes partial support for Fortran 77. It will recognize
4728 Fortran programs and can evaluate a subset of Fortran expressions, but
4729 variables and functions may not be handled correctly. GDB will work
4730 with G77, but does not yet know much about symbols emitted by other
4733 * Better HPUX support
4735 Most debugging facilities now work on dynamic executables for HPPAs
4736 running hpux9 or later. You can attach to running dynamically linked
4737 processes, but by default the dynamic libraries will be read-only, so
4738 for instance you won't be able to put breakpoints in them. To change
4739 that behavior do the following before running the program:
4745 This will cause the libraries to be mapped private and read-write.
4746 To revert to the normal behavior, do this:
4752 You cannot set breakpoints or examine data in the library until after
4753 the library is loaded if the function/data symbols do not have
4756 GDB can now also read debug symbols produced by the HP C compiler on
4757 HPPAs (sorry, no C++, Fortran or 68k support).
4759 * Target byte order now dynamically selectable
4761 You can choose which byte order to use with a target system, via the
4762 commands "set endian big" and "set endian little", and you can see the
4763 current setting by using "show endian". You can also give the command
4764 "set endian auto", in which case GDB will use the byte order
4765 associated with the executable. Currently, only embedded MIPS
4766 configurations support dynamic selection of target byte order.
4768 * New DOS host serial code
4770 This version uses DPMI interrupts to handle buffered I/O, so you
4771 no longer need to run asynctsr when debugging boards connected to
4774 *** Changes in GDB-4.13:
4776 * New "complete" command
4778 This lists all the possible completions for the rest of the line, if it
4779 were to be given as a command itself. This is intended for use by emacs.
4781 * Trailing space optional in prompt
4783 "set prompt" no longer adds a space for you after the prompt you set. This
4784 allows you to set a prompt which ends in a space or one that does not.
4786 * Breakpoint hit counts
4788 "info break" now displays a count of the number of times the breakpoint
4789 has been hit. This is especially useful in conjunction with "ignore"; you
4790 can ignore a large number of breakpoint hits, look at the breakpoint info
4791 to see how many times the breakpoint was hit, then run again, ignoring one
4792 less than that number, and this will get you quickly to the last hit of
4795 * Ability to stop printing at NULL character
4797 "set print null-stop" will cause GDB to stop printing the characters of
4798 an array when the first NULL is encountered. This is useful when large
4799 arrays actually contain only short strings.
4801 * Shared library breakpoints
4803 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4804 breakpoints in shared libraries before the executable is run.
4806 * Hardware watchpoints
4808 There is a new hardware breakpoint for the watch command for sparclite
4809 targets. See gdb/sparclite/hw_breakpoint.note.
4811 Hardware watchpoints are also now supported under GNU/Linux.
4815 Annotations have been added. These are for use with graphical interfaces,
4816 and are still experimental. Currently only gdba.el uses these.
4818 * Improved Irix 5 support
4820 GDB now works properly with Irix 5.2.
4822 * Improved HPPA support
4824 GDB now works properly with the latest GCC and GAS.
4826 * New native configurations
4828 Sequent PTX4 i[34]86-sequent-ptx4
4829 HPPA running OSF/1 hppa*-*-osf*
4830 Atari TT running SVR4 m68*-*-sysv4*
4831 RS/6000 LynxOS rs6000-*-lynxos*
4835 OS/9000 i[34]86-*-os9k
4836 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4839 * Hitachi SH7000 and E7000-PC ICE support
4841 There is now support for communicating with the Hitachi E7000-PC ICE.
4842 This is available automatically when GDB is configured for the SH.
4846 As usual, a variety of small fixes and improvements, both generic
4847 and configuration-specific. See the ChangeLog for more detail.
4849 *** Changes in GDB-4.12:
4851 * Irix 5 is now supported
4855 GDB-4.12 on the HPPA has a number of changes which make it unable
4856 to debug the output from the currently released versions of GCC and
4857 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4858 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4859 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4862 *** Changes in GDB-4.11:
4864 * User visible changes:
4868 The "set remotedebug" option is now consistent between the mips remote
4869 target, remote targets using the gdb-specific protocol, UDI (AMD's
4870 debug protocol for the 29k) and the 88k bug monitor. It is now an
4871 integer specifying a debug level (normally 0 or 1, but 2 means more
4872 debugging info for the mips target).
4874 * DEC Alpha native support
4876 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4877 debug info, but GDB works fairly well with the DEC compiler and should
4878 work with a future GCC release. See the README file for a few
4879 Alpha-specific notes.
4881 * Preliminary thread implementation
4883 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4885 * LynxOS native and target support for 386
4887 This release has been hosted on LynxOS 2.2, and also can be configured
4888 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4891 * Improvements in C++ mangling/demangling.
4893 This release has much better g++ debugging, specifically in name
4894 mangling/demangling, virtual function calls, print virtual table,
4895 call methods, ...etc.
4897 *** Changes in GDB-4.10:
4899 * User visible changes:
4901 Remote debugging using the GDB-specific (`target remote') protocol now
4902 supports the `load' command. This is only useful if you have some
4903 other way of getting the stub to the target system, and you can put it
4904 somewhere in memory where it won't get clobbered by the download.
4906 Filename completion now works.
4908 When run under emacs mode, the "info line" command now causes the
4909 arrow to point to the line specified. Also, "info line" prints
4910 addresses in symbolic form (as well as hex).
4912 All vxworks based targets now support a user settable option, called
4913 vxworks-timeout. This option represents the number of seconds gdb
4914 should wait for responses to rpc's. You might want to use this if
4915 your vxworks target is, perhaps, a slow software simulator or happens
4916 to be on the far side of a thin network line.
4920 This release contains support for using a DEC alpha as a GDB host for
4921 cross debugging. Native alpha debugging is not supported yet.
4924 *** Changes in GDB-4.9:
4928 This is the first GDB release which is accompanied by a matching testsuite.
4929 The testsuite requires installation of dejagnu, which should be available
4930 via ftp from most sites that carry GNU software.
4934 'Cfront' style demangling has had its name changed to 'ARM' style, to
4935 emphasize that it was written from the specifications in the C++ Annotated
4936 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4937 disclaimers, it still generated too much confusion with users attempting to
4938 use gdb with AT&T cfront.
4942 GDB now uses a standard remote interface to a simulator library.
4943 So far, the library contains simulators for the Zilog Z8001/2, the
4944 Hitachi H8/300, H8/500 and Super-H.
4946 * New targets supported
4948 H8/300 simulator h8300-hitachi-hms or h8300hms
4949 H8/500 simulator h8500-hitachi-hms or h8500hms
4950 SH simulator sh-hitachi-hms or sh
4951 Z8000 simulator z8k-zilog-none or z8ksim
4952 IDT MIPS board over serial line mips-idt-ecoff
4954 Cross-debugging to GO32 targets is supported. It requires a custom
4955 version of the i386-stub.c module which is integrated with the
4956 GO32 memory extender.
4958 * New remote protocols
4960 MIPS remote debugging protocol.
4962 * New source languages supported
4964 This version includes preliminary support for Chill, a Pascal like language
4965 used by telecommunications companies. Chill support is also being integrated
4966 into the GNU compiler, but we don't know when it will be publically available.
4969 *** Changes in GDB-4.8:
4971 * HP Precision Architecture supported
4973 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4974 version of this support was available as a set of patches from the
4975 University of Utah. GDB does not support debugging of programs
4976 compiled with the HP compiler, because HP will not document their file
4977 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4978 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4980 Many problems in the preliminary version have been fixed.
4982 * Faster and better demangling
4984 We have improved template demangling and fixed numerous bugs in the GNU style
4985 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4986 character types (wchar_t) are now supported. Demangling of each symbol is now
4987 only done once, and is cached when the symbol table for a file is read in.
4988 This results in a small increase in memory usage for C programs, a moderate
4989 increase in memory usage for C++ programs, and a fantastic speedup in
4992 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4993 from the specifications in the Annotated Reference Manual, which AT&T's
4994 compiler does not actually implement.
4996 * G++ multiple inheritance compiler problem
4998 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4999 inheritance lattices was reworked to properly discover ambiguities. We
5000 recently found an example which causes this new algorithm to fail in a
5001 very subtle way, producing bad debug information for those classes.
5002 The file 'gcc.patch' (in this directory) can be applied to gcc to
5003 circumvent the problem. A future GCC release will contain a complete
5006 The previous G++ debug info problem (mentioned below for the gdb-4.7
5007 release) is fixed in gcc version 2.3.2.
5009 * Improved configure script
5011 The `configure' script will now attempt to guess your system type if
5012 you don't supply a host system type. The old scheme of supplying a
5013 host system triplet is preferable over using this. All the magic is
5014 done in the new `config.guess' script. Examine it for details.
5016 We have also brought our configure script much more in line with the FSF's
5017 version. It now supports the --with-xxx options. In particular,
5018 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5019 The resulting GDB will not be able to read arbitrary object file formats --
5020 only the format ``expected'' to be used on the configured target system.
5021 We hope to make this the default in a future release.
5023 * Documentation improvements
5025 There's new internal documentation on how to modify GDB, and how to
5026 produce clean changes to the code. We implore people to read it
5027 before submitting changes.
5029 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5030 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5031 `info' files are also provided. To build `info' files from scratch,
5032 you will need the latest `makeinfo' release, which will be available in
5033 a future texinfo-X.Y release.
5035 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5036 We're not sure exactly which versions have this problem, but it has
5037 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5038 or better. If that isn't possible, there is a patch in
5039 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5040 around this problem.
5044 GDB now supports array constants that can be used in expressions typed in by
5045 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5046 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5049 The new directory `gdb/sparclite' contains a program that demonstrates
5050 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5052 * New native hosts supported
5054 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5055 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5057 * New targets supported
5059 AMD 29k family via UDI a29k-amd-udi or udi29k
5061 * New file formats supported
5063 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5064 HPUX core files, and SCO 3.2v2 core files.
5068 Attaching to processes now works again; thanks for the many bug reports.
5070 We have also stomped on a bunch of core dumps caused by
5071 printf_filtered("%s") problems.
5073 We eliminated a copyright problem on the rpc and ptrace header files
5074 for VxWorks, which was discovered at the last minute during the 4.7
5075 release. You should now be able to build a VxWorks GDB.
5077 You can now interrupt gdb while an attached process is running. This
5078 will cause the attached process to stop, and give control back to GDB.
5080 We fixed problems caused by using too many file descriptors
5081 for reading symbols from object files and libraries. This was
5082 especially a problem for programs that used many (~100) shared
5085 The `step' command now only enters a subroutine if there is line number
5086 information for the subroutine. Otherwise it acts like the `next'
5087 command. Previously, `step' would enter subroutines if there was
5088 any debugging information about the routine. This avoids problems
5089 when using `cc -g1' on MIPS machines.
5091 * Internal improvements
5093 GDB's internal interfaces have been improved to make it easier to support
5094 debugging of multiple languages in the future.
5096 GDB now uses a common structure for symbol information internally.
5097 Minimal symbols (derived from linkage symbols in object files), partial
5098 symbols (from a quick scan of debug information), and full symbols
5099 contain a common subset of information, making it easier to write
5100 shared code that handles any of them.
5102 * New command line options
5104 We now accept --silent as an alias for --quiet.
5108 The memory-mapped-malloc library is now licensed under the GNU Library
5109 General Public License.
5111 *** Changes in GDB-4.7:
5113 * Host/native/target split
5115 GDB has had some major internal surgery to untangle the support for
5116 hosts and remote targets. Now, when you configure GDB for a remote
5117 target, it will no longer load in all of the support for debugging
5118 local programs on the host. When fully completed and tested, this will
5119 ensure that arbitrary host/target combinations are possible.
5121 The primary conceptual shift is to separate the non-portable code in
5122 GDB into three categories. Host specific code is required any time GDB
5123 is compiled on that host, regardless of the target. Target specific
5124 code relates to the peculiarities of the target, but can be compiled on
5125 any host. Native specific code is everything else: it can only be
5126 built when the host and target are the same system. Child process
5127 handling and core file support are two common `native' examples.
5129 GDB's use of /proc for controlling Unix child processes is now cleaner.
5130 It has been split out into a single module under the `target_ops' vector,
5131 plus two native-dependent functions for each system that uses /proc.
5133 * New hosts supported
5135 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5136 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5137 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5139 * New targets supported
5141 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5142 68030 and CPU32 m68030-*-*, m68332-*-*
5144 * New native hosts supported
5146 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5147 (386bsd is not well tested yet)
5148 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5150 * New file formats supported
5152 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5153 supports reading of `a.out.adobe' object files, which are an a.out
5154 format extended with minimal information about multiple sections.
5158 `show copying' is the same as the old `info copying'.
5159 `show warranty' is the same as `info warrantee'.
5160 These were renamed for consistency. The old commands continue to work.
5162 `info handle' is a new alias for `info signals'.
5164 You can now define pre-command hooks, which attach arbitrary command
5165 scripts to any command. The commands in the hook will be executed
5166 prior to the user's command. You can also create a hook which will be
5167 executed whenever the program stops. See gdb.texinfo.
5171 We now deal with Cfront style name mangling, and can even extract type
5172 info from mangled symbols. GDB can automatically figure out which
5173 symbol mangling style your C++ compiler uses.
5175 Calling of methods and virtual functions has been improved as well.
5179 The crash that occured when debugging Sun Ansi-C compiled binaries is
5180 fixed. This was due to mishandling of the extra N_SO stabs output
5183 We also finally got Ultrix 4.2 running in house, and fixed core file
5184 support, with help from a dozen people on the net.
5186 John M. Farrell discovered that the reason that single-stepping was so
5187 slow on all of the Mips based platforms (primarily SGI and DEC) was
5188 that we were trying to demangle and lookup a symbol used for internal
5189 purposes on every instruction that was being stepped through. Changing
5190 the name of that symbol so that it couldn't be mistaken for a C++
5191 mangled symbol sped things up a great deal.
5193 Rich Pixley sped up symbol lookups in general by getting much smarter
5194 about when C++ symbol mangling is necessary. This should make symbol
5195 completion (TAB on the command line) much faster. It's not as fast as
5196 we'd like, but it's significantly faster than gdb-4.6.
5200 A new user controllable variable 'call_scratch_address' can
5201 specify the location of a scratch area to be used when GDB
5202 calls a function in the target. This is necessary because the
5203 usual method of putting the scratch area on the stack does not work
5204 in systems that have separate instruction and data spaces.
5206 We integrated changes to support the 29k UDI (Universal Debugger
5207 Interface), but discovered at the last minute that we didn't have all
5208 of the appropriate copyright paperwork. We are working with AMD to
5209 resolve this, and hope to have it available soon.
5213 We have sped up the remote serial line protocol, especially for targets
5214 with lots of registers. It now supports a new `expedited status' ('T')
5215 message which can be used in place of the existing 'S' status message.
5216 This allows the remote stub to send only the registers that GDB
5217 needs to make a quick decision about single-stepping or conditional
5218 breakpoints, eliminating the need to fetch the entire register set for
5219 each instruction being stepped through.
5221 The GDB remote serial protocol now implements a write-through cache for
5222 registers, only re-reading the registers if the target has run.
5224 There is also a new remote serial stub for SPARC processors. You can
5225 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5226 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5227 processor with a serial port.
5231 Configure.in files have become much easier to read and modify. A new
5232 `table driven' format makes it more obvious what configurations are
5233 supported, and what files each one uses.
5237 There is a new opcodes library which will eventually contain all of the
5238 disassembly routines and opcode tables. At present, it only contains
5239 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5240 disassembler (binutils/objdump) to share these routines.
5242 The libiberty library is now copylefted under the GNU Library General
5243 Public License. This allows more liberal use, and was done so libg++
5244 can use it. This makes no difference to GDB, since the Library License
5245 grants all the rights from the General Public License.
5249 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5250 reference to the stabs symbol info used by the debugger. It is (as far
5251 as we know) the only published document on this fascinating topic. We
5252 encourage you to read it, compare it to the stabs information on your
5253 system, and send improvements on the document in general (to
5256 And, of course, many bugs have been fixed.
5259 *** Changes in GDB-4.6:
5261 * Better support for C++ function names
5263 GDB now accepts as input the "demangled form" of C++ overloaded function
5264 names and member function names, and can do command completion on such names
5265 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5266 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5267 Make use of command completion, it is your friend.
5269 GDB also now accepts a variety of C++ mangled symbol formats. They are
5270 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5271 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5272 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5273 for the list of formats.
5275 * G++ symbol mangling problem
5277 Recent versions of gcc have a bug in how they emit debugging information for
5278 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5279 directory) can be applied to gcc to fix the problem. Alternatively, if you
5280 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5281 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5282 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5285 * New 'maintenance' command
5287 All of the commands related to hacking GDB internals have been moved out of
5288 the main command set, and now live behind the 'maintenance' command. This
5289 can also be abbreviated as 'mt'. The following changes were made:
5291 dump-me -> maintenance dump-me
5292 info all-breakpoints -> maintenance info breakpoints
5293 printmsyms -> maintenance print msyms
5294 printobjfiles -> maintenance print objfiles
5295 printpsyms -> maintenance print psymbols
5296 printsyms -> maintenance print symbols
5298 The following commands are new:
5300 maintenance demangle Call internal GDB demangler routine to
5301 demangle a C++ link name and prints the result.
5302 maintenance print type Print a type chain for a given symbol
5304 * Change to .gdbinit file processing
5306 We now read the $HOME/.gdbinit file before processing the argv arguments
5307 (e.g. reading symbol files or core files). This allows global parameters to
5308 be set, which will apply during the symbol reading. The ./.gdbinit is still
5309 read after argv processing.
5311 * New hosts supported
5313 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5315 GNU/Linux support i386-unknown-linux or linux
5317 We are also including code to support the HP/PA running BSD and HPUX. This
5318 is almost guaranteed not to work, as we didn't have time to test or build it
5319 for this release. We are including it so that the more adventurous (or
5320 masochistic) of you can play with it. We also had major problems with the
5321 fact that the compiler that we got from HP doesn't support the -g option.
5324 * New targets supported
5326 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5328 * More smarts about finding #include files
5330 GDB now remembers the compilation directory for all include files, and for
5331 all files from which C is generated (like yacc and lex sources). This
5332 greatly improves GDB's ability to find yacc/lex sources, and include files,
5333 especially if you are debugging your program from a directory different from
5334 the one that contains your sources.
5336 We also fixed a bug which caused difficulty with listing and setting
5337 breakpoints in include files which contain C code. (In the past, you had to
5338 try twice in order to list an include file that you hadn't looked at before.)
5340 * Interesting infernals change
5342 GDB now deals with arbitrary numbers of sections, where the symbols for each
5343 section must be relocated relative to that section's landing place in the
5344 target's address space. This work was needed to support ELF with embedded
5345 stabs used by Solaris-2.0.
5347 * Bug fixes (of course!)
5349 There have been loads of fixes for the following things:
5350 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5351 i960, stabs, DOS(GO32), procfs, etc...
5353 See the ChangeLog for details.
5355 *** Changes in GDB-4.5:
5357 * New machines supported (host and target)
5359 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5361 SGI Irix-4.x mips-sgi-irix4 or iris4
5363 * New malloc package
5365 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5366 Mmalloc is capable of handling mutiple heaps of memory. It is also
5367 capable of saving a heap to a file, and then mapping it back in later.
5368 This can be used to greatly speedup the startup of GDB by using a
5369 pre-parsed symbol table which lives in a mmalloc managed heap. For
5370 more details, please read mmalloc/mmalloc.texi.
5374 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5375 'help info proc' for details.
5377 * MIPS ecoff symbol table format
5379 The code that reads MIPS symbol table format is now supported on all hosts.
5380 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5383 * File name changes for MS-DOS
5385 Many files in the config directories have been renamed to make it easier to
5386 support GDB on MS-DOSe systems (which have very restrictive file name
5387 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5388 environment) is close to working but has some remaining problems. Note
5389 that debugging of DOS programs is not supported, due to limitations
5390 in the ``operating system'', but it can be used to host cross-debugging.
5392 * Cross byte order fixes
5394 Many fixes have been made to support cross debugging of Sparc and MIPS
5395 targets from hosts whose byte order differs.
5397 * New -mapped and -readnow options
5399 If memory-mapped files are available on your system through the 'mmap'
5400 system call, you can use the -mapped option on the `file' or
5401 `symbol-file' commands to cause GDB to write the symbols from your
5402 program into a reusable file. If the program you are debugging is
5403 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5404 Future GDB debugging sessions will notice the presence of this file,
5405 and will quickly map in symbol information from it, rather than reading
5406 the symbol table from the executable program. Using the '-mapped'
5407 option in a GDB `file' or `symbol-file' command has the same effect as
5408 starting GDB with the '-mapped' command-line option.
5410 You can cause GDB to read the entire symbol table immediately by using
5411 the '-readnow' option with any of the commands that load symbol table
5412 information (or on the GDB command line). This makes the command
5413 slower, but makes future operations faster.
5415 The -mapped and -readnow options are typically combined in order to
5416 build a `fred.syms' file that contains complete symbol information.
5417 A simple GDB invocation to do nothing but build a `.syms' file for future
5420 gdb -batch -nx -mapped -readnow programname
5422 The `.syms' file is specific to the host machine on which GDB is run.
5423 It holds an exact image of GDB's internal symbol table. It cannot be
5424 shared across multiple host platforms.
5426 * longjmp() handling
5428 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5429 siglongjmp() without losing control. This feature has not yet been ported to
5430 all systems. It currently works on many 386 platforms, all MIPS-based
5431 platforms (SGI, DECstation, etc), and Sun3/4.
5435 Preliminary work has been put in to support the new Solaris OS from Sun. At
5436 this time, it can control and debug processes, but it is not capable of
5441 As always, many many bug fixes. The major areas were with g++, and mipsread.
5442 People using the MIPS-based platforms should experience fewer mysterious
5443 crashes and trashed symbol tables.
5445 *** Changes in GDB-4.4:
5447 * New machines supported (host and target)
5449 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5451 BSD Reno on Vax vax-dec-bsd
5452 Ultrix on Vax vax-dec-ultrix
5454 * New machines supported (target)
5456 AMD 29000 embedded, using EBMON a29k-none-none
5460 GDB continues to improve its handling of C++. `References' work better.
5461 The demangler has also been improved, and now deals with symbols mangled as
5462 per the Annotated C++ Reference Guide.
5464 GDB also now handles `stabs' symbol information embedded in MIPS
5465 `ecoff' symbol tables. Since the ecoff format was not easily
5466 extensible to handle new languages such as C++, this appeared to be a
5467 good way to put C++ debugging info into MIPS binaries. This option
5468 will be supported in the GNU C compiler, version 2, when it is
5471 * New features for SVR4
5473 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5474 shared libraries. Debugging dynamically linked programs should present
5475 only minor differences from debugging statically linked programs.
5477 The `info proc' command will print out information about any process
5478 on an SVR4 system (including the one you are debugging). At the moment,
5479 it prints the address mappings of the process.
5481 If you bring up GDB on another SVR4 system, please send mail to
5484 * Better dynamic linking support in SunOS
5486 Reading symbols from shared libraries which contain debugging symbols
5487 now works properly. However, there remain issues such as automatic
5488 skipping of `transfer vector' code during function calls, which
5489 make it harder to debug code in a shared library, than to debug the
5490 same code linked statically.
5494 GDB is now using the latest `getopt' routines from the FSF. This
5495 version accepts the -- prefix for options with long names. GDB will
5496 continue to accept the old forms (-option and +option) as well.
5497 Various single letter abbreviations for options have been explicity
5498 added to the option table so that they won't get overshadowed in the
5499 future by other options that begin with the same letter.
5503 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5504 Many assorted bugs have been handled. Many more remain to be handled.
5505 See the various ChangeLog files (primarily in gdb and bfd) for details.
5508 *** Changes in GDB-4.3:
5510 * New machines supported (host and target)
5512 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5513 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5514 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5516 * Almost SCO Unix support
5518 We had hoped to support:
5519 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5520 (except for core file support), but we discovered very late in the release
5521 that it has problems with process groups that render gdb unusable. Sorry
5522 about that. I encourage people to fix it and post the fixes.
5524 * Preliminary ELF and DWARF support
5526 GDB can read ELF object files on System V Release 4, and can handle
5527 debugging records for C, in DWARF format, in ELF files. This support
5528 is preliminary. If you bring up GDB on another SVR4 system, please
5534 GDB now uses the latest `readline' library. One user-visible change
5535 is that two tabs will list possible command completions, which previously
5536 required typing M-? (meta-question mark, or ESC ?).
5540 The `stepi' bug that many of you noticed has been squashed.
5541 Many bugs in C++ have been handled. Many more remain to be handled.
5542 See the various ChangeLog files (primarily in gdb and bfd) for details.
5544 * State of the MIPS world (in case you wondered):
5546 GDB can understand the symbol tables emitted by the compilers
5547 supplied by most vendors of MIPS-based machines, including DEC. These
5548 symbol tables are in a format that essentially nobody else uses.
5550 Some versions of gcc come with an assembler post-processor called
5551 mips-tfile. This program is required if you want to do source-level
5552 debugging of gcc-compiled programs. I believe FSF does not ship
5553 mips-tfile with gcc version 1, but it will eventually come with gcc
5556 Debugging of g++ output remains a problem. g++ version 1.xx does not
5557 really support it at all. (If you're lucky, you should be able to get
5558 line numbers and stack traces to work, but no parameters or local
5559 variables.) With some work it should be possible to improve the
5562 When gcc version 2 is released, you will have somewhat better luck.
5563 However, even then you will get confusing results for inheritance and
5566 We will eventually provide full debugging of g++ output on
5567 DECstations. This will probably involve some kind of stabs-in-ecoff
5568 encapulation, but the details have not been worked out yet.
5571 *** Changes in GDB-4.2:
5573 * Improved configuration
5575 Only one copy of `configure' exists now, and it is not self-modifying.
5576 Porting BFD is simpler.
5580 The `step' and `next' commands now only stop at the first instruction
5581 of a source line. This prevents the multiple stops that used to occur
5582 in switch statements, for-loops, etc. `Step' continues to stop if a
5583 function that has debugging information is called within the line.
5587 Lots of small bugs fixed. More remain.
5589 * New host supported (not target)
5591 Intel 386 PC clone running Mach i386-none-mach
5594 *** Changes in GDB-4.1:
5596 * Multiple source language support
5598 GDB now has internal scaffolding to handle several source languages.
5599 It determines the type of each source file from its filename extension,
5600 and will switch expression parsing and number formatting to match the
5601 language of the function in the currently selected stack frame.
5602 You can also specifically set the language to be used, with
5603 `set language c' or `set language modula-2'.
5607 GDB now has preliminary support for the GNU Modula-2 compiler,
5608 currently under development at the State University of New York at
5609 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5610 continue through the fall of 1991 and into 1992.
5612 Other Modula-2 compilers are currently not supported, and attempting to
5613 debug programs compiled with them will likely result in an error as the
5614 symbol table is read. Feel free to work on it, though!
5616 There are hooks in GDB for strict type checking and range checking,
5617 in the `Modula-2 philosophy', but they do not currently work.
5621 GDB can now write to executable and core files (e.g. patch
5622 a variable's value). You must turn this switch on, specify
5623 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5624 by assigning a new value to a variable. Modifications take
5627 * Automatic SunOS shared library reading
5629 When you run your program, GDB automatically determines where its
5630 shared libraries (if any) have been loaded, and reads their symbols.
5631 The `share' command is no longer needed. This also works when
5632 examining core files.
5636 You can specify the number of lines that the `list' command shows.
5639 * New machines supported (host and target)
5641 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5642 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5643 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5645 * New hosts supported (not targets)
5647 IBM RT/PC: romp-ibm-aix or rtpc
5649 * New targets supported (not hosts)
5651 AMD 29000 embedded with COFF a29k-none-coff
5652 AMD 29000 embedded with a.out a29k-none-aout
5653 Ultracomputer remote kernel debug a29k-nyu-kern
5655 * New remote interfaces
5661 *** Changes in GDB-4.0:
5665 Wide output is wrapped at good places to make the output more readable.
5667 Gdb now supports cross-debugging from a host machine of one type to a
5668 target machine of another type. Communication with the target system
5669 is over serial lines. The ``target'' command handles connecting to the
5670 remote system; the ``load'' command will download a program into the
5671 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5672 also supports debugging of realtime processes running under VxWorks,
5673 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5674 stub on the target system.
5676 New CPUs supported include the AMD 29000 and Intel 960.
5678 GDB now reads object files and symbol tables via a ``binary file''
5679 library, which allows a single copy of GDB to debug programs of multiple
5680 object file types such as a.out and coff.
5682 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5683 refcard.dvi and refcard.ps are available to format it).
5686 * Control-Variable user interface simplified
5688 All variables that control the operation of the debugger can be set
5689 by the ``set'' command, and displayed by the ``show'' command.
5691 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5692 ``Show prompt'' produces the response:
5693 Gdb's prompt is new-gdb=>.
5695 What follows are the NEW set commands. The command ``help set'' will
5696 print a complete list of old and new set commands. ``help set FOO''
5697 will give a longer description of the variable FOO. ``show'' will show
5698 all of the variable descriptions and their current settings.
5700 confirm on/off: Enables warning questions for operations that are
5701 hard to recover from, e.g. rerunning the program while
5702 it is already running. Default is ON.
5704 editing on/off: Enables EMACS style command line editing
5705 of input. Previous lines can be recalled with
5706 control-P, the current line can be edited with control-B,
5707 you can search for commands with control-R, etc.
5710 history filename NAME: NAME is where the gdb command history
5711 will be stored. The default is .gdb_history,
5712 or the value of the environment variable
5715 history size N: The size, in commands, of the command history. The
5716 default is 256, or the value of the environment variable
5719 history save on/off: If this value is set to ON, the history file will
5720 be saved after exiting gdb. If set to OFF, the
5721 file will not be saved. The default is OFF.
5723 history expansion on/off: If this value is set to ON, then csh-like
5724 history expansion will be performed on
5725 command line input. The default is OFF.
5727 radix N: Sets the default radix for input and output. It can be set
5728 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5729 in the current radix, so "set radix 10" is always a no-op.
5731 height N: This integer value is the number of lines on a page. Default
5732 is 24, the current `stty rows'' setting, or the ``li#''
5733 setting from the termcap entry matching the environment
5736 width N: This integer value is the number of characters on a line.
5737 Default is 80, the current `stty cols'' setting, or the ``co#''
5738 setting from the termcap entry matching the environment
5741 Note: ``set screensize'' is obsolete. Use ``set height'' and
5742 ``set width'' instead.
5744 print address on/off: Print memory addresses in various command displays,
5745 such as stack traces and structure values. Gdb looks
5746 more ``symbolic'' if you turn this off; it looks more
5747 ``machine level'' with it on. Default is ON.
5749 print array on/off: Prettyprint arrays. New convenient format! Default
5752 print demangle on/off: Print C++ symbols in "source" form if on,
5755 print asm-demangle on/off: Same, for assembler level printouts
5758 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5761 * Support for Epoch Environment.
5763 The epoch environment is a version of Emacs v18 with windowing. One
5764 new command, ``inspect'', is identical to ``print'', except that if you
5765 are running in the epoch environment, the value is printed in its own
5769 * Support for Shared Libraries
5771 GDB can now debug programs and core files that use SunOS shared libraries.
5772 Symbols from a shared library cannot be referenced
5773 before the shared library has been linked with the program (this
5774 happens after you type ``run'' and before the function main() is entered).
5775 At any time after this linking (including when examining core files
5776 from dynamically linked programs), gdb reads the symbols from each
5777 shared library when you type the ``sharedlibrary'' command.
5778 It can be abbreviated ``share''.
5780 sharedlibrary REGEXP: Load shared object library symbols for files
5781 matching a unix regular expression. No argument
5782 indicates to load symbols for all shared libraries.
5784 info sharedlibrary: Status of loaded shared libraries.
5789 A watchpoint stops execution of a program whenever the value of an
5790 expression changes. Checking for this slows down execution
5791 tremendously whenever you are in the scope of the expression, but is
5792 quite useful for catching tough ``bit-spreader'' or pointer misuse
5793 problems. Some machines such as the 386 have hardware for doing this
5794 more quickly, and future versions of gdb will use this hardware.
5796 watch EXP: Set a watchpoint (breakpoint) for an expression.
5798 info watchpoints: Information about your watchpoints.
5800 delete N: Deletes watchpoint number N (same as breakpoints).
5801 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5802 enable N: Re-enables watchpoint number N (same as breakpoints).
5805 * C++ multiple inheritance
5807 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5810 * C++ exception handling
5812 Gdb now supports limited C++ exception handling. Besides the existing
5813 ability to breakpoint on an exception handler, gdb can breakpoint on
5814 the raising of an exception (before the stack is peeled back to the
5817 catch FOO: If there is a FOO exception handler in the dynamic scope,
5818 set a breakpoint to catch exceptions which may be raised there.
5819 Multiple exceptions (``catch foo bar baz'') may be caught.
5821 info catch: Lists all exceptions which may be caught in the
5822 current stack frame.
5825 * Minor command changes
5827 The command ``call func (arg, arg, ...)'' now acts like the print
5828 command, except it does not print or save a value if the function's result
5829 is void. This is similar to dbx usage.
5831 The ``up'' and ``down'' commands now always print the frame they end up
5832 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5833 frames without printing.
5835 * New directory command
5837 'dir' now adds directories to the FRONT of the source search path.
5838 The path starts off empty. Source files that contain debug information
5839 about the directory in which they were compiled can be found even
5840 with an empty path; Sun CC and GCC include this information. If GDB can't
5841 find your source file in the current directory, type "dir .".
5843 * Configuring GDB for compilation
5845 For normal use, type ``./configure host''. See README or gdb.texinfo
5848 GDB now handles cross debugging. If you are remotely debugging between
5849 two different machines, type ``./configure host -target=targ''.
5850 Host is the machine where GDB will run; targ is the machine
5851 where the program that you are debugging will run.