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 ** gdb.Objfile objects have a new method "add_separate_debug_file".
27 ** A new event "gdb.clear_objfiles" has been added, triggered when
28 selecting a new file to debug.
29 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
31 * New Python-based convenience functions:
33 ** $_caller_is(name [, number_of_frames])
34 ** $_caller_matches(regexp [, number_of_frames])
35 ** $_any_caller_is(name [, number_of_frames])
36 ** $_any_caller_matches(regexp [, number_of_frames])
40 queue-signal signal-name-or-number
41 Queue a signal to be delivered to the thread when it is resumed.
43 add-auto-load-scripts-directory directory
44 Add entries to the list of directories from which to load auto-loaded
47 * On resume, GDB now always passes the signal the program had stopped
48 for to the thread the signal was sent to, even if the user changed
49 threads before resuming. Previously GDB would often (but not
50 always) deliver the signal to the thread that happens to be current
53 * Conversely, the "signal" command now consistently delivers the
54 requested signal to the current thread. GDB now asks for
55 confirmation if the program had stopped for a signal and the user
56 switched threads meanwhile.
58 * "breakpoint always-inserted" modes "off" and "auto" merged.
60 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
61 won't remove breakpoints from the target until all threads stop,
62 even in non-stop mode. The "auto" mode has been removed, and "off"
63 is now the default mode.
67 ** The -list-thread-groups command outputs an exit-code field for
68 inferiors that have exited.
72 Support for these obsolete configurations has been removed.
74 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
75 SGI Irix-5.x mips-*-irix5*
76 SGI Irix-6.x mips-*-irix6*
77 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
78 VAX running Ultrix vax-*-ultrix*
80 *** Changes in GDB 7.8
82 * New command line options
85 This is an alias for the --data-directory option.
87 * GDB supports printing and modifying of variable length automatic arrays
88 as specified in ISO C99.
90 * The ARM simulator now supports instruction level tracing
91 with or without disassembly.
95 GDB now has support for scripting using Guile. Whether this is
96 available is determined at configure time.
97 Guile version 2.0 or greater is required.
98 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
100 * New commands (for set/show, see "New options" below)
104 Invoke CODE by passing it to the Guile interpreter.
108 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
110 info auto-load guile-scripts [regexp]
111 Print the list of automatically loaded Guile scripts.
113 * The source command is now capable of sourcing Guile scripts.
114 This feature is dependent on the debugger being built with Guile support.
118 set print symbol-loading (off|brief|full)
119 show print symbol-loading
120 Control whether to print informational messages when loading symbol
121 information for a file. The default is "full", but when debugging
122 programs with large numbers of shared libraries the amount of output
125 set guile print-stack (none|message|full)
126 show guile print-stack
127 Show a stack trace when an error is encountered in a Guile script.
129 set auto-load guile-scripts (on|off)
130 show auto-load guile-scripts
131 Control auto-loading of Guile script files.
133 maint ada set ignore-descriptive-types (on|off)
134 maint ada show ignore-descriptive-types
135 Control whether the debugger should ignore descriptive types in Ada
136 programs. The default is not to ignore the descriptive types. See
137 the user manual for more details on descriptive types and the intended
138 usage of this option.
140 set auto-connect-native-target
142 Control whether GDB is allowed to automatically connect to the
143 native target for the run, attach, etc. commands when not connected
144 to any target yet. See also "target native" below.
146 set record btrace replay-memory-access (read-only|read-write)
147 show record btrace replay-memory-access
148 Control what memory accesses are allowed during replay.
150 maint set target-async (on|off)
151 maint show target-async
152 This controls whether GDB targets operate in synchronous or
153 asynchronous mode. Normally the default is asynchronous, if it is
154 available; but this can be changed to more easily debug problems
155 occurring only in synchronous mode.
157 set mi-async (on|off)
159 Control whether MI asynchronous mode is preferred. This supersedes
160 "set target-async" of previous GDB versions.
162 * "set target-async" is deprecated as a CLI option and is now an alias
163 for "set mi-async" (only puts MI into async mode).
165 * Background execution commands (e.g., "c&", "s&", etc.) are now
166 possible ``out of the box'' if the target supports them. Previously
167 the user would need to explicitly enable the possibility with the
168 "set target-async on" command.
170 * New features in the GDB remote stub, GDBserver
172 ** New option --debug-format=option1[,option2,...] allows one to add
173 additional text to each output. At present only timestamps
174 are supported: --debug-format=timestamps.
175 Timestamps can also be turned on with the
176 "monitor set debug-format timestamps" command from GDB.
178 * The 'record instruction-history' command now starts counting instructions
179 at one. This also affects the instruction ranges reported by the
180 'record function-call-history' command when given the /i modifier.
182 * The command 'record function-call-history' supports a new modifier '/c' to
183 indent the function names based on their call stack depth.
184 The fields for the '/i' and '/l' modifier have been reordered.
185 The source line range is now prefixed with 'at'.
186 The instruction range is now prefixed with 'inst'.
187 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
188 "record instruction-history" and "list" commands.
190 * The ranges given as arguments to the 'record function-call-history' and
191 'record instruction-history' commands are now inclusive.
193 * The btrace record target now supports the 'record goto' command.
194 For locations inside the execution trace, the back trace is computed
195 based on the information stored in the execution trace.
197 * The btrace record target supports limited reverse execution and replay.
198 The target does not record data and therefore does not allow reading
201 * The "catch syscall" command now works on s390*-linux* targets.
203 * The "compare-sections" command is no longer specific to target
204 remote. It now works with all targets.
206 * All native targets are now consistently called "native".
207 Consequently, the "target child", "target GNU", "target djgpp",
208 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
209 commands have been replaced with "target native". The QNX/NTO port
210 leaves the "procfs" target in place and adds a "native" target for
211 consistency with other ports. The impact on users should be minimal
212 as these commands previously either throwed an error, or were
213 no-ops. The target's name is visible in the output of the following
214 commands: "help target", "info target", "info files", "maint print
217 * The "target native" command now connects to the native target. This
218 can be used to launch native programs even when "set
219 auto-connect-native-target" is set to off.
221 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
223 * Support for Intel(R) AVX-512 registers on GNU/Linux.
224 Support displaying and modifying Intel(R) AVX-512 registers
225 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
229 qXfer:btrace:read's annex
230 The qXfer:btrace:read packet supports a new annex 'delta' to read
231 branch trace incrementally.
235 ** Valid Python operations on gdb.Value objects representing
236 structs/classes invoke the corresponding overloaded operators if
238 ** New `Xmethods' feature in the Python API. Xmethods are
239 additional methods or replacements for existing methods of a C++
240 class. This feature is useful for those cases where a method
241 defined in C++ source code could be inlined or optimized out by
242 the compiler, making it unavailable to GDB.
245 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
247 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
248 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
249 its alias "share", instead.
251 * The commands "set remotebaud" and "show remotebaud" are no longer
252 supported. Use "set serial baud" and "show serial baud" (respectively)
257 ** A new option "-gdb-set mi-async" replaces "-gdb-set
258 target-async". The latter is left as a deprecated alias of the
259 former for backward compatibility. If the target supports it,
260 CLI background execution commands are now always possible by
261 default, independently of whether the frontend stated a
262 preference for asynchronous execution with "-gdb-set mi-async".
263 Previously "-gdb-set target-async off" affected both MI execution
264 commands and CLI execution commands.
266 *** Changes in GDB 7.7
268 * Improved support for process record-replay and reverse debugging on
269 arm*-linux* targets. Support for thumb32 and syscall instruction
270 recording has been added.
272 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
274 * GDB now supports Fission DWP file format version 2.
275 http://gcc.gnu.org/wiki/DebugFission
277 * New convenience function "$_isvoid", to check whether an expression
278 is void. A void expression is an expression where the type of the
279 result is "void". For example, some convenience variables may be
280 "void" when evaluated (e.g., "$_exitcode" before the execution of
281 the program being debugged; or an undefined convenience variable).
282 Another example, when calling a function whose return type is
285 * The "maintenance print objfiles" command now takes an optional regexp.
287 * The "catch syscall" command now works on arm*-linux* targets.
289 * GDB now consistently shows "<not saved>" when printing values of
290 registers the debug info indicates have not been saved in the frame
291 and there's nowhere to retrieve them from
292 (callee-saved/call-clobbered registers):
297 (gdb) info registers rax
300 Before, the former would print "<optimized out>", and the latter
301 "*value not available*".
303 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
308 ** Frame filters and frame decorators have been added.
309 ** Temporary breakpoints are now supported.
310 ** Line tables representation has been added.
311 ** New attribute 'parent_type' for gdb.Field objects.
312 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
313 ** New attribute 'name' for gdb.Type objects.
317 Nios II ELF nios2*-*-elf
318 Nios II GNU/Linux nios2*-*-linux
319 Texas Instruments MSP430 msp430*-*-elf
321 * Removed native configurations
323 Support for these a.out NetBSD and OpenBSD obsolete configurations has
324 been removed. ELF variants of these configurations are kept supported.
326 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
327 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
328 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
329 i[34567]86-*-openbsd3.[0-3]
330 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
331 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
332 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
336 Like "catch throw", but catches a re-thrown exception.
338 Renamed from old "maint check-symtabs".
340 Perform consistency checks on symtabs.
342 Expand symtabs matching an optional regexp.
345 Display the details of GDB configure-time options.
347 maint set|show per-command
348 maint set|show per-command space
349 maint set|show per-command time
350 maint set|show per-command symtab
351 Enable display of per-command gdb resource usage.
353 remove-symbol-file FILENAME
354 remove-symbol-file -a ADDRESS
355 Remove a symbol file added via add-symbol-file. The file to remove
356 can be identified by its filename or by an address that lies within
357 the boundaries of this symbol file in memory.
360 info exceptions REGEXP
361 Display the list of Ada exceptions defined in the program being
362 debugged. If provided, only the exceptions whose names match REGEXP
367 set debug symfile off|on
369 Control display of debugging info regarding reading symbol files and
370 symbol tables within those files
372 set print raw frame-arguments
373 show print raw frame-arguments
374 Set/show whether to print frame arguments in raw mode,
375 disregarding any defined pretty-printers.
377 set remote trace-status-packet
378 show remote trace-status-packet
379 Set/show the use of remote protocol qTStatus packet.
383 Control display of debugging messages related to Nios II targets.
387 Control whether target-assisted range stepping is enabled.
389 set startup-with-shell
390 show startup-with-shell
391 Specifies whether Unix child processes are started via a shell or
396 Use the target memory cache for accesses to the code segment. This
397 improves performance of remote debugging (particularly disassembly).
399 * You can now use a literal value 'unlimited' for options that
400 interpret 0 or -1 as meaning "unlimited". E.g., "set
401 trace-buffer-size unlimited" is now an alias for "set
402 trace-buffer-size -1" and "set height unlimited" is now an alias for
405 * The "set debug symtab-create" debugging option of GDB has been changed to
406 accept a verbosity level. 0 means "off", 1 provides basic debugging
407 output, and values of 2 or greater provides more verbose output.
409 * New command-line options
411 Display the details of GDB configure-time options.
413 * The command 'tsave' can now support new option '-ctf' to save trace
414 buffer in Common Trace Format.
416 * Newly installed $prefix/bin/gcore acts as a shell interface for the
419 * GDB now implements the the C++ 'typeid' operator.
421 * The new convenience variable $_exception holds the exception being
422 thrown or caught at an exception-related catchpoint.
424 * The exception-related catchpoints, like "catch throw", now accept a
425 regular expression which can be used to filter exceptions by type.
427 * The new convenience variable $_exitsignal is automatically set to
428 the terminating signal number when the program being debugged dies
429 due to an uncaught signal.
433 ** All MI commands now accept an optional "--language" option.
434 Support for this feature can be verified by using the "-list-features"
435 command, which should contain "language-option".
437 ** The new command -info-gdb-mi-command allows the user to determine
438 whether a GDB/MI command is supported or not.
440 ** The "^error" result record returned when trying to execute an undefined
441 GDB/MI command now provides a variable named "code" whose content is the
442 "undefined-command" error code. Support for this feature can be verified
443 by using the "-list-features" command, which should contain
444 "undefined-command-error-code".
446 ** The -trace-save MI command can optionally save trace buffer in Common
449 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
451 ** The command -data-list-register-values now accepts an optional
452 "--skip-unavailable" option. When used, only the available registers
455 ** The new command -trace-frame-collected dumps collected variables,
456 computed expressions, tvars, memory and registers in a traceframe.
458 ** The commands -stack-list-locals, -stack-list-arguments and
459 -stack-list-variables now accept an option "--skip-unavailable".
460 When used, only the available locals or arguments are displayed.
462 ** The -exec-run command now accepts an optional "--start" option.
463 When used, the command follows the same semantics as the "start"
464 command, stopping the program's execution at the start of its
465 main subprogram. Support for this feature can be verified using
466 the "-list-features" command, which should contain
467 "exec-run-start-option".
469 ** The new commands -catch-assert and -catch-exceptions insert
470 catchpoints stopping the program when Ada exceptions are raised.
472 ** The new command -info-ada-exceptions provides the equivalent of
473 the new "info exceptions" command.
475 * New system-wide configuration scripts
476 A GDB installation now provides scripts suitable for use as system-wide
477 configuration scripts for the following systems:
481 * GDB now supports target-assigned range stepping with remote targets.
482 This improves the performance of stepping source lines by reducing
483 the number of control packets from/to GDB. See "New remote packets"
486 * GDB now understands the element 'tvar' in the XML traceframe info.
487 It has the id of the collected trace state variables.
489 * On S/390 targets that provide the transactional-execution feature,
490 the program interruption transaction diagnostic block (TDB) is now
491 represented as a number of additional "registers" in GDB.
497 The vCont packet supports a new 'r' action, that tells the remote
498 stub to step through an address range itself, without GDB
499 involvemement at each single-step.
501 qXfer:libraries-svr4:read's annex
502 The previously unused annex of the qXfer:libraries-svr4:read packet
503 is now used to support passing an argument list. The remote stub
504 reports support for this argument list to GDB's qSupported query.
505 The defined arguments are "start" and "prev", used to reduce work
506 necessary for library list updating, resulting in significant
509 * New features in the GDB remote stub, GDBserver
511 ** GDBserver now supports target-assisted range stepping. Currently
512 enabled on x86/x86_64 GNU/Linux targets.
514 ** GDBserver now adds element 'tvar' in the XML in the reply to
515 'qXfer:traceframe-info:read'. It has the id of the collected
516 trace state variables.
518 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
521 * New 'z' formatter for printing and examining memory, this displays the
522 value as hexadecimal zero padded on the left to the size of the type.
524 * GDB can now use Windows x64 unwinding data.
526 * The "set remotebaud" command has been replaced by "set serial baud".
527 Similarly, "show remotebaud" has been replaced by "show serial baud".
528 The "set remotebaud" and "show remotebaud" commands are still available
529 to provide backward compatibility with older versions of GDB.
531 *** Changes in GDB 7.6
533 * Target record has been renamed to record-full.
534 Record/replay is now enabled with the "record full" command.
535 This also affects settings that are associated with full record/replay
536 that have been moved from "set/show record" to "set/show record full":
538 set|show record full insn-number-max
539 set|show record full stop-at-limit
540 set|show record full memory-query
542 * A new record target "record-btrace" has been added. The new target
543 uses hardware support to record the control-flow of a process. It
544 does not support replaying the execution, but it implements the
545 below new commands for investigating the recorded execution log.
546 This new recording method can be enabled using:
550 The "record-btrace" target is only available on Intel Atom processors
551 and requires a Linux kernel 2.6.32 or later.
553 * Two new commands have been added for record/replay to give information
554 about the recorded execution without having to replay the execution.
555 The commands are only supported by "record btrace".
557 record instruction-history prints the execution history at
558 instruction granularity
560 record function-call-history prints the execution history at
563 * New native configurations
565 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
566 FreeBSD/powerpc powerpc*-*-freebsd
567 x86_64/Cygwin x86_64-*-cygwin*
568 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
572 ARM AArch64 aarch64*-*-elf
573 ARM AArch64 GNU/Linux aarch64*-*-linux
574 Lynx 178 PowerPC powerpc-*-lynx*178
575 x86_64/Cygwin x86_64-*-cygwin*
576 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
578 * If the configured location of system.gdbinit file (as given by the
579 --with-system-gdbinit option at configure time) is in the
580 data-directory (as specified by --with-gdb-datadir at configure
581 time) or in one of its subdirectories, then GDB will look for the
582 system-wide init file in the directory specified by the
583 --data-directory command-line option.
585 * New command line options:
587 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
588 other initialization files, unlike -nx which disables all of them.
590 * Removed command line options
592 -epoch This was used by the gdb mode in Epoch, an ancient fork of
595 * The 'ptype' and 'whatis' commands now accept an argument to control
598 * 'info proc' now works on some core files.
602 ** Vectors can be created with gdb.Type.vector.
604 ** Python's atexit.register now works in GDB.
606 ** Types can be pretty-printed via a Python API.
608 ** Python 3 is now supported (in addition to Python 2.4 or later)
610 ** New class gdb.Architecture exposes GDB's internal representation
611 of architecture in the Python API.
613 ** New method Frame.architecture returns the gdb.Architecture object
614 corresponding to the frame's architecture.
616 * New Python-based convenience functions:
618 ** $_memeq(buf1, buf2, length)
619 ** $_streq(str1, str2)
621 ** $_regex(str, regex)
623 * The 'cd' command now defaults to using '~' (the home directory) if not
626 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
627 default for GCC since November 2000.
629 * The command 'forward-search' can now be abbreviated as 'fo'.
631 * The command 'info tracepoints' can now display 'installed on target'
632 or 'not installed on target' for each non-pending location of tracepoint.
634 * New configure options
636 --enable-libmcheck/--disable-libmcheck
637 By default, development versions are built with -lmcheck on hosts
638 that support it, in order to help track memory corruption issues.
639 Release versions, on the other hand, are built without -lmcheck
640 by default. The --enable-libmcheck/--disable-libmcheck configure
641 options allow the user to override that default.
642 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
643 This configure option allows the user to build GDB with
644 libbabeltrace using which GDB can read Common Trace Format data.
646 * New commands (for set/show, see "New options" below)
649 Catch signals. This is similar to "handle", but allows commands and
650 conditions to be attached.
653 List the BFDs known to GDB.
655 python-interactive [command]
657 Start a Python interactive prompt, or evaluate the optional command
658 and print the result of expressions.
661 "py" is a new alias for "python".
663 enable type-printer [name]...
664 disable type-printer [name]...
665 Enable or disable type printers.
669 ** For the Renesas Super-H architecture, the "regs" command has been removed
670 (has been deprecated in GDB 7.5), and "info all-registers" should be used
675 set print type methods (on|off)
676 show print type methods
677 Control whether method declarations are displayed by "ptype".
678 The default is to show them.
680 set print type typedefs (on|off)
681 show print type typedefs
682 Control whether typedef definitions are displayed by "ptype".
683 The default is to show them.
685 set filename-display basename|relative|absolute
686 show filename-display
687 Control the way in which filenames is displayed.
688 The default is "relative", which preserves previous behavior.
690 set trace-buffer-size
691 show trace-buffer-size
692 Request target to change the size of trace buffer.
694 set remote trace-buffer-size-packet auto|on|off
695 show remote trace-buffer-size-packet
696 Control the use of the remote protocol `QTBuffer:size' packet.
700 Control display of debugging messages related to ARM AArch64.
703 set debug coff-pe-read
704 show debug coff-pe-read
705 Control display of debugging messages related to reading of COFF/PE
710 Control display of debugging messages related to Mach-O symbols
713 set debug notification
714 show debug notification
715 Control display of debugging info for async remote notification.
719 ** Command parameter changes are now notified using new async record
720 "=cmd-param-changed".
721 ** Trace frame changes caused by command "tfind" are now notified using
722 new async record "=traceframe-changed".
723 ** The creation, deletion and modification of trace state variables
724 are now notified using new async records "=tsv-created",
725 "=tsv-deleted" and "=tsv-modified".
726 ** The start and stop of process record are now notified using new
727 async record "=record-started" and "=record-stopped".
728 ** Memory changes are now notified using new async record
730 ** The data-disassemble command response will include a "fullname" field
731 containing the absolute file name when source has been requested.
732 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
733 command, to allow pattern filling of memory areas.
734 ** New commands "-catch-load"/"-catch-unload" added for intercepting
735 library load/unload events.
736 ** The response to breakpoint commands and breakpoint async records
737 includes an "installed" field containing a boolean state about each
738 non-pending tracepoint location is whether installed on target or not.
739 ** Output of the "-trace-status" command includes a "trace-file" field
740 containing the name of the trace file being examined. This field is
741 optional, and only present when examining a trace file.
742 ** The "fullname" field is now always present along with the "file" field,
743 even if the file cannot be found by GDB.
745 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
746 You must have the LZMA library available when configuring GDB for this
747 feature to be enabled. For more information, see:
748 http://fedoraproject.org/wiki/Features/MiniDebugInfo
753 Set the size of trace buffer. The remote stub reports support for this
754 packet to gdb's qSupported query.
757 Enable Branch Trace Store (BTS)-based branch tracing for the current
758 thread. The remote stub reports support for this packet to gdb's
762 Disable branch tracing for the current thread. The remote stub reports
763 support for this packet to gdb's qSupported query.
766 Read the traced branches for the current thread. The remote stub
767 reports support for this packet to gdb's qSupported query.
769 *** Changes in GDB 7.5
771 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
772 for more x32 ABI info.
774 * GDB now supports access to MIPS DSP registers on Linux targets.
776 * GDB now supports debugging microMIPS binaries.
778 * The "info os" command on GNU/Linux can now display information on
779 several new classes of objects managed by the operating system:
780 "info os procgroups" lists process groups
781 "info os files" lists file descriptors
782 "info os sockets" lists internet-domain sockets
783 "info os shm" lists shared-memory regions
784 "info os semaphores" lists semaphores
785 "info os msg" lists message queues
786 "info os modules" lists loaded kernel modules
788 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
789 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
790 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
791 options and inspect the probe arguments using the new $_probe_arg family
792 of convenience variables. You can obtain more information about SystemTap
793 in <http://sourceware.org/systemtap/>.
795 * GDB now supports reversible debugging on ARM, it allows you to
796 debug basic ARM and THUMB instructions, and provides
797 record/replay support.
799 * The option "symbol-reloading" has been deleted as it is no longer used.
803 ** GDB commands implemented in Python can now be put in command class
806 ** The "maint set python print-stack on|off" is now deleted.
808 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
809 apply "flag enum"-style pretty-printing to any enum.
811 ** gdb.lookup_symbol can now work when there is no current frame.
813 ** gdb.Symbol now has a 'line' attribute, holding the line number in
814 the source at which the symbol was defined.
816 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
817 method 'value'. The former indicates whether the symbol needs a
818 frame in order to compute its value, and the latter computes the
821 ** A new method 'referenced_value' on gdb.Value objects which can
822 dereference pointer as well as C++ reference values.
824 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
825 which return the global and static blocks (as gdb.Block objects),
826 of the underlying symbol table, respectively.
828 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
829 object associated with a PC value.
831 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
832 of the address range occupied by code for the current source line.
834 * Go language support.
835 GDB now supports debugging programs written in the Go programming
838 * GDBserver now supports stdio connections.
839 E.g. (gdb) target remote | ssh myhost gdbserver - hello
841 * The binary "gdbtui" can no longer be built or installed.
842 Use "gdb -tui" instead.
844 * GDB will now print "flag" enums specially. A flag enum is one where
845 all the enumerator values have no bits in common when pairwise
846 "and"ed. When printing a value whose type is a flag enum, GDB will
847 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
848 (gdb) print (enum E) 3
851 * The filename part of a linespec will now match trailing components
852 of a source file name. For example, "break gcc/expr.c:1000" will
853 now set a breakpoint in build/gcc/expr.c, but not
856 * The "info proc" and "generate-core-file" commands will now also
857 work on remote targets connected to GDBserver on Linux.
859 * The command "info catch" has been removed. It has been disabled
862 * The "catch exception" and "catch assert" commands now accept
863 a condition at the end of the command, much like the "break"
864 command does. For instance:
866 (gdb) catch exception Constraint_Error if Barrier = True
868 Previously, it was possible to add a condition to such catchpoints,
869 but it had to be done as a second step, after the catchpoint had been
870 created, using the "condition" command.
872 * The "info static-tracepoint-marker" command will now also work on
873 native Linux targets with in-process agent.
875 * GDB can now set breakpoints on inlined functions.
877 * The .gdb_index section has been updated to include symbols for
878 inlined functions. GDB will ignore older .gdb_index sections by
879 default, which could cause symbol files to be loaded more slowly
880 until their .gdb_index sections can be recreated. The new command
881 "set use-deprecated-index-sections on" will cause GDB to use any older
882 .gdb_index sections it finds. This will restore performance, but the
883 ability to set breakpoints on inlined functions will be lost in symbol
884 files with older .gdb_index sections.
886 The .gdb_index section has also been updated to record more information
887 about each symbol. This speeds up the "info variables", "info functions"
888 and "info types" commands when used with programs having the .gdb_index
889 section, as well as speeding up debugging with shared libraries using
890 the .gdb_index section.
892 * Ada support for GDB/MI Variable Objects has been added.
894 * GDB can now support 'breakpoint always-inserted mode' in 'record'
899 ** New command -info-os is the MI equivalent of "info os".
901 ** Output logs ("set logging" and related) now include MI output.
905 ** "set use-deprecated-index-sections on|off"
906 "show use-deprecated-index-sections on|off"
907 Controls the use of deprecated .gdb_index sections.
909 ** "catch load" and "catch unload" can be used to stop when a shared
910 library is loaded or unloaded, respectively.
912 ** "enable count" can be used to auto-disable a breakpoint after
915 ** "info vtbl" can be used to show the virtual method tables for
916 C++ and Java objects.
918 ** "explore" and its sub commands "explore value" and "explore type"
919 can be used to recursively explore values and types of
920 expressions. These commands are available only if GDB is
921 configured with '--with-python'.
923 ** "info auto-load" shows status of all kinds of auto-loaded files,
924 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
925 sequences of commands files, "info auto-load python-scripts"
926 shows status of auto-loading Python script files,
927 "info auto-load local-gdbinit" shows status of loading init file
928 (.gdbinit) from current directory and "info auto-load libthread-db" shows
929 status of inferior specific thread debugging shared library loading.
931 ** "info auto-load-scripts", "set auto-load-scripts on|off"
932 and "show auto-load-scripts" commands have been deprecated, use their
933 "info auto-load python-scripts", "set auto-load python-scripts on|off"
934 and "show auto-load python-scripts" counterparts instead.
936 ** "dprintf location,format,args..." creates a dynamic printf, which
937 is basically a breakpoint that does a printf and immediately
938 resumes your program's execution, so it is like a printf that you
939 can insert dynamically at runtime instead of at compiletime.
941 ** "set print symbol"
943 Controls whether GDB attempts to display the symbol, if any,
944 corresponding to addresses it prints. This defaults to "on", but
945 you can set it to "off" to restore GDB's previous behavior.
947 * Deprecated commands
949 ** For the Renesas Super-H architecture, the "regs" command has been
950 deprecated, and "info all-registers" should be used instead.
954 Renesas RL78 rl78-*-elf
955 HP OpenVMS ia64 ia64-hp-openvms*
957 * GDBserver supports evaluation of breakpoint conditions. When
958 support is advertised by GDBserver, GDB may be told to send the
959 breakpoint conditions in bytecode form to GDBserver. GDBserver
960 will only report the breakpoint trigger to GDB when its condition
966 show mips compression
967 Select the compressed ISA encoding used in functions that have no symbol
968 information available. The encoding can be set to either of:
971 and is updated automatically from ELF file flags if available.
973 set breakpoint condition-evaluation
974 show breakpoint condition-evaluation
975 Control whether breakpoint conditions are evaluated by GDB ("host") or by
976 GDBserver ("target"). Default option "auto" chooses the most efficient
978 This option can improve debugger efficiency depending on the speed of the
982 Disable auto-loading globally.
985 Show auto-loading setting of all kinds of auto-loaded files.
987 set auto-load gdb-scripts on|off
988 show auto-load gdb-scripts
989 Control auto-loading of GDB canned sequences of commands files.
991 set auto-load python-scripts on|off
992 show auto-load python-scripts
993 Control auto-loading of Python script files.
995 set auto-load local-gdbinit on|off
996 show auto-load local-gdbinit
997 Control loading of init file (.gdbinit) from current directory.
999 set auto-load libthread-db on|off
1000 show auto-load libthread-db
1001 Control auto-loading of inferior specific thread debugging shared library.
1003 set auto-load scripts-directory <dir1>[:<dir2>...]
1004 show auto-load scripts-directory
1005 Set a list of directories from which to load auto-loaded scripts.
1006 Automatically loaded Python scripts and GDB scripts are located in one
1007 of the directories listed by this option.
1008 The delimiter (':' above) may differ according to the host platform.
1010 set auto-load safe-path <dir1>[:<dir2>...]
1011 show auto-load safe-path
1012 Set a list of directories from which it is safe to auto-load files.
1013 The delimiter (':' above) may differ according to the host platform.
1015 set debug auto-load on|off
1016 show debug auto-load
1017 Control display of debugging info for auto-loading the files above.
1019 set dprintf-style gdb|call|agent
1021 Control the way in which a dynamic printf is performed; "gdb"
1022 requests a GDB printf command, while "call" causes dprintf to call a
1023 function in the inferior. "agent" requests that the target agent
1024 (such as GDBserver) do the printing.
1026 set dprintf-function <expr>
1027 show dprintf-function
1028 set dprintf-channel <expr>
1029 show dprintf-channel
1030 Set the function and optional first argument to the call when using
1031 the "call" style of dynamic printf.
1033 set disconnected-dprintf on|off
1034 show disconnected-dprintf
1035 Control whether agent-style dynamic printfs continue to be in effect
1036 after GDB disconnects.
1038 * New configure options
1040 --with-auto-load-dir
1041 Configure default value for the 'set auto-load scripts-directory'
1042 setting above. It defaults to '$debugdir:$datadir/auto-load',
1043 $debugdir representing global debugging info directories (available
1044 via 'show debug-file-directory') and $datadir representing GDB's data
1045 directory (available via 'show data-directory').
1047 --with-auto-load-safe-path
1048 Configure default value for the 'set auto-load safe-path' setting
1049 above. It defaults to the --with-auto-load-dir setting.
1051 --without-auto-load-safe-path
1052 Set 'set auto-load safe-path' to '/', effectively disabling this
1055 * New remote packets
1057 z0/z1 conditional breakpoints extension
1059 The z0/z1 breakpoint insertion packets have been extended to carry
1060 a list of conditional expressions over to the remote stub depending on the
1061 condition evaluation mode. The use of this extension can be controlled
1062 via the "set remote conditional-breakpoints-packet" command.
1066 Specify the signals which the remote stub may pass to the debugged
1067 program without GDB involvement.
1069 * New command line options
1071 --init-command=FILE, -ix Like --command, -x but execute it
1072 before loading inferior.
1073 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1074 execute it before loading inferior.
1076 *** Changes in GDB 7.4
1078 * GDB now handles ambiguous linespecs more consistently; the existing
1079 FILE:LINE support has been expanded to other types of linespecs. A
1080 breakpoint will now be set on all matching locations in all
1081 inferiors, and locations will be added or removed according to
1084 * GDB now allows you to skip uninteresting functions and files when
1085 stepping with the "skip function" and "skip file" commands.
1087 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1088 and "show remote hardware-watchpoint-length-limit". These allows to
1089 set or show the maximum length limit (in bytes) of a remote
1090 target hardware watchpoint.
1092 This allows e.g. to use "unlimited" hardware watchpoints with the
1093 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1094 watchpoints are slower than real hardware watchpoints but are
1095 significantly faster than gdb software watchpoints.
1099 ** The register_pretty_printer function in module gdb.printing now takes
1100 an optional `replace' argument. If True, the new printer replaces any
1103 ** The "maint set python print-stack on|off" command has been
1104 deprecated and will be deleted in GDB 7.5.
1105 A new command: "set python print-stack none|full|message" has
1106 replaced it. Additionally, the default for "print-stack" is
1107 now "message", which just prints the error message without
1110 ** A prompt substitution hook (prompt_hook) is now available to the
1113 ** A new Python module, gdb.prompt has been added to the GDB Python
1114 modules library. This module provides functionality for
1115 escape sequences in prompts (used by set/show
1116 extended-prompt). These escape sequences are replaced by their
1117 corresponding value.
1119 ** Python commands and convenience-functions located in
1120 'data-directory'/python/gdb/command and
1121 'data-directory'/python/gdb/function are now automatically loaded
1124 ** Blocks now provide four new attributes. global_block and
1125 static_block will return the global and static blocks
1126 respectively. is_static and is_global are boolean attributes
1127 that indicate if the block is one of those two types.
1129 ** Symbols now provide the "type" attribute, the type of the symbol.
1131 ** The "gdb.breakpoint" function has been deprecated in favor of
1134 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1135 of a function. This class is based on the "finish" command
1136 available in the CLI.
1138 ** Type objects for struct and union types now allow access to
1139 the fields using standard Python dictionary (mapping) methods.
1140 For example, "some_type['myfield']" now works, as does
1141 "some_type.items()".
1143 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1146 ** A new function, "deep_items" has been added to the gdb.types
1147 module in the GDB Python modules library. This function returns
1148 an iterator over the fields of a struct or union type. Unlike
1149 the standard Python "iteritems" method, it will recursively traverse
1150 any anonymous fields.
1154 ** "*stopped" events can report several new "reason"s, such as
1157 ** Breakpoint changes are now notified using new async records, like
1158 "=breakpoint-modified".
1160 ** New command -ada-task-info.
1162 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1163 $sdir specifies the default system locations of shared libraries.
1164 $pdir specifies the directory where the libpthread used by the application
1167 GDB no longer looks in $sdir and $pdir after it has searched the directories
1168 mentioned in libthread-db-search-path. If you want to search those
1169 directories, they must be specified in libthread-db-search-path.
1170 The default value of libthread-db-search-path on GNU/Linux and Solaris
1171 systems is now "$sdir:$pdir".
1173 $pdir is not supported by gdbserver, it is currently ignored.
1174 $sdir is supported by gdbserver.
1176 * New configure option --with-iconv-bin.
1177 When using the internationalization support like the one in the GNU C
1178 library, GDB will invoke the "iconv" program to get a list of supported
1179 character sets. If this program lives in a non-standard location, one can
1180 use this option to specify where to find it.
1182 * When natively debugging programs on PowerPC BookE processors running
1183 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1184 watchpoints, which specify a mask in addition to an address to watch.
1185 The mask specifies that some bits of an address (the bits which are
1186 reset in the mask) should be ignored when matching the address accessed
1187 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1188 section in the user manual for more details.
1190 * The new option --once causes GDBserver to stop listening for connections once
1191 the first connection is made. The listening port used by GDBserver will
1192 become available after that.
1194 * New commands "info macros" and "alias" have been added.
1196 * New function parameters suffix @entry specifies value of function parameter
1197 at the time the function got called. Entry values are available only since
1203 "!" is now an alias of the "shell" command.
1204 Note that no space is needed between "!" and SHELL COMMAND.
1208 watch EXPRESSION mask MASK_VALUE
1209 The watch command now supports the mask argument which allows creation
1210 of masked watchpoints, if the current architecture supports this feature.
1212 info auto-load-scripts [REGEXP]
1213 This command was formerly named "maintenance print section-scripts".
1214 It is now generally useful and is no longer a maintenance-only command.
1216 info macro [-all] [--] MACRO
1217 The info macro command has new options `-all' and `--'. The first for
1218 printing all definitions of a macro. The second for explicitly specifying
1219 the end of arguments and the beginning of the macro name in case the macro
1220 name starts with a hyphen.
1222 collect[/s] EXPRESSIONS
1223 The tracepoint collect command now takes an optional modifier "/s"
1224 that directs it to dereference pointer-to-character types and
1225 collect the bytes of memory up to a zero byte. The behavior is
1226 similar to what you see when you use the regular print command on a
1227 string. An optional integer following the "/s" sets a bound on the
1228 number of bytes that will be collected.
1231 The trace start command now interprets any supplied arguments as a
1232 note to be recorded with the trace run, with an effect similar to
1233 setting the variable trace-notes.
1236 The trace stop command now interprets any arguments as a note to be
1237 mentioned along with the tstatus report that the trace was stopped
1238 with a command. The effect is similar to setting the variable
1241 * Tracepoints can now be enabled and disabled at any time after a trace
1242 experiment has been started using the standard "enable" and "disable"
1243 commands. It is now possible to start a trace experiment with no enabled
1244 tracepoints; GDB will display a warning, but will allow the experiment to
1245 begin, assuming that tracepoints will be enabled as needed while the trace
1248 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1249 locations with 4-byte instructions, when they were previously
1250 limited to locations with instructions of 5 bytes or longer.
1254 set debug dwarf2-read
1255 show debug dwarf2-read
1256 Turns on or off display of debugging messages related to reading
1257 DWARF debug info. The default is off.
1259 set debug symtab-create
1260 show debug symtab-create
1261 Turns on or off display of debugging messages related to symbol table
1262 creation. The default is off.
1265 show extended-prompt
1266 Set the GDB prompt, and allow escape sequences to be inserted to
1267 display miscellaneous information (see 'help set extended-prompt'
1268 for the list of sequences). This prompt (and any information
1269 accessed through the escape sequences) is updated every time the
1270 prompt is displayed.
1272 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1273 show print entry-values
1274 Set printing of frame argument values at function entry. In some cases
1275 GDB can determine the value of function argument which was passed by the
1276 function caller, even if the value was modified inside the called function.
1278 set debug entry-values
1279 show debug entry-values
1280 Control display of debugging info for determining frame argument values at
1281 function entry and virtual tail call frames.
1283 set basenames-may-differ
1284 show basenames-may-differ
1285 Set whether a source file may have multiple base names.
1286 (A "base name" is the name of a file with the directory part removed.
1287 Example: The base name of "/home/user/hello.c" is "hello.c".)
1288 If set, GDB will canonicalize file names (e.g., expand symlinks)
1289 before comparing them. Canonicalization is an expensive operation,
1290 but it allows the same file be known by more than one base name.
1291 If not set (the default), all source files are assumed to have just
1292 one base name, and gdb will do file name comparisons more efficiently.
1298 Set a user name and notes for the current and any future trace runs.
1299 This is useful for long-running and/or disconnected traces, to
1300 inform others (or yourself) as to who is running the trace, supply
1301 contact information, or otherwise explain what is going on.
1303 set trace-stop-notes
1304 show trace-stop-notes
1305 Set a note attached to the trace run, that is displayed when the
1306 trace has been stopped by a tstop command. This is useful for
1307 instance as an explanation, if you are stopping a trace run that was
1308 started by someone else.
1310 * New remote packets
1314 Dynamically enable a tracepoint in a started trace experiment.
1318 Dynamically disable a tracepoint in a started trace experiment.
1322 Set the user and notes of the trace run.
1326 Query the current status of a tracepoint.
1330 Query the minimum length of instruction at which a fast tracepoint may
1333 * Dcache size (number of lines) and line-size are now runtime-configurable
1334 via "set dcache line" and "set dcache line-size" commands.
1338 Texas Instruments TMS320C6x tic6x-*-*
1342 Renesas RL78 rl78-*-elf
1344 *** Changes in GDB 7.3.1
1346 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1348 *** Changes in GDB 7.3
1350 * GDB has a new command: "thread find [REGEXP]".
1351 It finds the thread id whose name, target id, or thread extra info
1352 matches the given regular expression.
1354 * The "catch syscall" command now works on mips*-linux* targets.
1356 * The -data-disassemble MI command now supports modes 2 and 3 for
1357 dumping the instruction opcodes.
1359 * New command line options
1361 -data-directory DIR Specify DIR as the "data-directory".
1362 This is mostly for testing purposes.
1364 * The "maint set python auto-load on|off" command has been renamed to
1365 "set auto-load-scripts on|off".
1367 * GDB has a new command: "set directories".
1368 It is like the "dir" command except that it replaces the
1369 source path list instead of augmenting it.
1371 * GDB now understands thread names.
1373 On GNU/Linux, "info threads" will display the thread name as set by
1374 prctl or pthread_setname_np.
1376 There is also a new command, "thread name", which can be used to
1377 assign a name internally for GDB to display.
1380 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1381 has been integrated into GDB.
1385 ** The function gdb.Write now accepts an optional keyword 'stream'.
1386 This keyword, when provided, will direct the output to either
1387 stdout, stderr, or GDB's logging output.
1389 ** Parameters can now be be sub-classed in Python, and in particular
1390 you may implement the get_set_doc and get_show_doc functions.
1391 This improves how Parameter set/show documentation is processed
1392 and allows for more dynamic content.
1394 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1395 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1396 have an is_valid method.
1398 ** Breakpoints can now be sub-classed in Python, and in particular
1399 you may implement a 'stop' function that is executed each time
1400 the inferior reaches that breakpoint.
1402 ** New function gdb.lookup_global_symbol looks up a global symbol.
1404 ** GDB values in Python are now callable if the value represents a
1405 function. For example, if 'some_value' represents a function that
1406 takes two integer parameters and returns a value, you can call
1407 that function like so:
1409 result = some_value (10,20)
1411 ** Module gdb.types has been added.
1412 It contains a collection of utilities for working with gdb.Types objects:
1413 get_basic_type, has_field, make_enum_dict.
1415 ** Module gdb.printing has been added.
1416 It contains utilities for writing and registering pretty-printers.
1417 New classes: PrettyPrinter, SubPrettyPrinter,
1418 RegexpCollectionPrettyPrinter.
1419 New function: register_pretty_printer.
1421 ** New commands "info pretty-printers", "enable pretty-printer" and
1422 "disable pretty-printer" have been added.
1424 ** gdb.parameter("directories") is now available.
1426 ** New function gdb.newest_frame returns the newest frame in the
1429 ** The gdb.InferiorThread class has a new "name" attribute. This
1430 holds the thread's name.
1432 ** Python Support for Inferior events.
1433 Python scripts can add observers to be notified of events
1434 occurring in the process being debugged.
1435 The following events are currently supported:
1436 - gdb.events.cont Continue event.
1437 - gdb.events.exited Inferior exited event.
1438 - gdb.events.stop Signal received, and Breakpoint hit events.
1442 ** GDB now puts template parameters in scope when debugging in an
1443 instantiation. For example, if you have:
1445 template<int X> int func (void) { return X; }
1447 then if you step into func<5>, "print X" will show "5". This
1448 feature requires proper debuginfo support from the compiler; it
1449 was added to GCC 4.5.
1451 ** The motion commands "next", "finish", "until", and "advance" now
1452 work better when exceptions are thrown. In particular, GDB will
1453 no longer lose control of the inferior; instead, the GDB will
1454 stop the inferior at the point at which the exception is caught.
1455 This functionality requires a change in the exception handling
1456 code that was introduced in GCC 4.5.
1458 * GDB now follows GCC's rules on accessing volatile objects when
1459 reading or writing target state during expression evaluation.
1460 One notable difference to prior behavior is that "print x = 0"
1461 no longer generates a read of x; the value of the assignment is
1462 now always taken directly from the value being assigned.
1464 * GDB now has some support for using labels in the program's source in
1465 linespecs. For instance, you can use "advance label" to continue
1466 execution to a label.
1468 * GDB now has support for reading and writing a new .gdb_index
1469 section. This section holds a fast index of DWARF debugging
1470 information and can be used to greatly speed up GDB startup and
1471 operation. See the documentation for `save gdb-index' for details.
1473 * The "watch" command now accepts an optional "-location" argument.
1474 When used, this causes GDB to watch the memory referred to by the
1475 expression. Such a watchpoint is never deleted due to it going out
1478 * GDB now supports thread debugging of core dumps on GNU/Linux.
1480 GDB now activates thread debugging using the libthread_db library
1481 when debugging GNU/Linux core dumps, similarly to when debugging
1482 live processes. As a result, when debugging a core dump file, GDB
1483 is now able to display pthread_t ids of threads. For example, "info
1484 threads" shows the same output as when debugging the process when it
1485 was live. In earlier releases, you'd see something like this:
1488 * 1 LWP 6780 main () at main.c:10
1490 While now you see this:
1493 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1495 It is also now possible to inspect TLS variables when debugging core
1498 When debugging a core dump generated on a machine other than the one
1499 used to run GDB, you may need to point GDB at the correct
1500 libthread_db library with the "set libthread-db-search-path"
1501 command. See the user manual for more details on this command.
1503 * When natively debugging programs on PowerPC BookE processors running
1504 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1505 which stop execution of the inferior whenever it executes an instruction
1506 at any address within the specified range. See the "PowerPC Embedded"
1507 section in the user manual for more details.
1509 * New features in the GDB remote stub, GDBserver
1511 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1512 and i686 LynxOS (version 5.x).
1514 ** GDBserver is now supported on Blackfin Linux.
1516 * New native configurations
1518 ia64 HP-UX ia64-*-hpux*
1522 Analog Devices, Inc. Blackfin Processor bfin-*
1524 * Ada task switching is now supported on sparc-elf targets when
1525 debugging a program using the Ravenscar Profile. For more information,
1526 see the "Tasking Support when using the Ravenscar Profile" section
1527 in the GDB user manual.
1529 * Guile support was removed.
1531 * New features in the GNU simulator
1533 ** The --map-info flag lists all known core mappings.
1535 ** CFI flashes may be simulated via the "cfi" device.
1537 *** Changes in GDB 7.2
1539 * Shared library support for remote targets by default
1541 When GDB is configured for a generic, non-OS specific target, like
1542 for example, --target=arm-eabi or one of the many *-*-elf targets,
1543 GDB now queries remote stubs for loaded shared libraries using the
1544 `qXfer:libraries:read' packet. Previously, shared library support
1545 was always disabled for such configurations.
1549 ** Argument Dependent Lookup (ADL)
1551 In C++ ADL lookup directs function search to the namespaces of its
1552 arguments even if the namespace has not been imported.
1562 Here the compiler will search for `foo' in the namespace of 'b'
1563 and find A::foo. GDB now supports this. This construct is commonly
1564 used in the Standard Template Library for operators.
1566 ** Improved User Defined Operator Support
1568 In addition to member operators, GDB now supports lookup of operators
1569 defined in a namespace and imported with a `using' directive, operators
1570 defined in the global scope, operators imported implicitly from an
1571 anonymous namespace, and the ADL operators mentioned in the previous
1573 GDB now also supports proper overload resolution for all the previously
1574 mentioned flavors of operators.
1576 ** static const class members
1578 Printing of static const class members that are initialized in the
1579 class definition has been fixed.
1581 * Windows Thread Information Block access.
1583 On Windows targets, GDB now supports displaying the Windows Thread
1584 Information Block (TIB) structure. This structure is visible either
1585 by using the new command `info w32 thread-information-block' or, by
1586 dereferencing the new convenience variable named `$_tlb', a
1587 thread-specific pointer to the TIB. This feature is also supported
1588 when remote debugging using GDBserver.
1590 * Static tracepoints
1592 Static tracepoints are calls in the user program into a tracing
1593 library. One such library is a port of the LTTng kernel tracer to
1594 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1595 When debugging with GDBserver, GDB now supports combining the GDB
1596 tracepoint machinery with such libraries. For example: the user can
1597 use GDB to probe a static tracepoint marker (a call from the user
1598 program into the tracing library) with the new "strace" command (see
1599 "New commands" below). This creates a "static tracepoint" in the
1600 breakpoint list, that can be manipulated with the same feature set
1601 as fast and regular tracepoints. E.g., collect registers, local and
1602 global variables, collect trace state variables, and define
1603 tracepoint conditions. In addition, the user can collect extra
1604 static tracepoint marker specific data, by collecting the new
1605 $_sdata internal variable. When analyzing the trace buffer, you can
1606 inspect $_sdata like any other variable available to GDB. For more
1607 information, see the "Tracepoints" chapter in GDB user manual. New
1608 remote packets have been defined to support static tracepoints, see
1609 the "New remote packets" section below.
1611 * Better reconstruction of tracepoints after disconnected tracing
1613 GDB will attempt to download the original source form of tracepoint
1614 definitions when starting a trace run, and then will upload these
1615 upon reconnection to the target, resulting in a more accurate
1616 reconstruction of the tracepoints that are in use on the target.
1620 You can now exercise direct control over the ways that GDB can
1621 affect your program. For instance, you can disallow the setting of
1622 breakpoints, so that the program can run continuously (assuming
1623 non-stop mode). In addition, the "observer" variable is available
1624 to switch all of the different controls; in observer mode, GDB
1625 cannot affect the target's behavior at all, which is useful for
1626 tasks like diagnosing live systems in the field.
1628 * The new convenience variable $_thread holds the number of the
1631 * New remote packets
1635 Return the address of the Windows Thread Information Block of a given thread.
1639 In response to several of the tracepoint packets, the target may now
1640 also respond with a number of intermediate `qRelocInsn' request
1641 packets before the final result packet, to have GDB handle
1642 relocating an instruction to execute at a different address. This
1643 is particularly useful for stubs that support fast tracepoints. GDB
1644 reports support for this feature in the qSupported packet.
1648 List static tracepoint markers in the target program.
1652 List static tracepoint markers at a given address in the target
1655 qXfer:statictrace:read
1657 Read the static trace data collected (by a `collect $_sdata'
1658 tracepoint action). The remote stub reports support for this packet
1659 to gdb's qSupported query.
1663 Send the current settings of GDB's permission flags.
1667 Send part of the source (textual) form of a tracepoint definition,
1668 which includes location, conditional, and action list.
1670 * The source command now accepts a -s option to force searching for the
1671 script in the source search path even if the script name specifies
1674 * New features in the GDB remote stub, GDBserver
1676 - GDBserver now support tracepoints (including fast tracepoints, and
1677 static tracepoints). The feature is currently supported by the
1678 i386-linux and amd64-linux builds. See the "Tracepoints support
1679 in gdbserver" section in the manual for more information.
1681 GDBserver JIT compiles the tracepoint's conditional agent
1682 expression bytecode into native code whenever possible for low
1683 overhead dynamic tracepoints conditionals. For such tracepoints,
1684 an expression that examines program state is evaluated when the
1685 tracepoint is reached, in order to determine whether to capture
1686 trace data. If the condition is simple and false, processing the
1687 tracepoint finishes very quickly and no data is gathered.
1689 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1690 for static tracepoints support.
1692 - GDBserver now supports x86_64 Windows 64-bit debugging.
1694 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1695 it understands register description.
1697 * The --batch flag now disables pagination and queries.
1699 * X86 general purpose registers
1701 GDB now supports reading/writing byte, word and double-word x86
1702 general purpose registers directly. This means you can use, say,
1703 $ah or $ax to refer, respectively, to the byte register AH and
1704 16-bit word register AX that are actually portions of the 32-bit
1705 register EAX or 64-bit register RAX.
1707 * The `commands' command now accepts a range of breakpoints to modify.
1708 A plain `commands' following a command that creates multiple
1709 breakpoints affects all the breakpoints set by that command. This
1710 applies to breakpoints set by `rbreak', and also applies when a
1711 single `break' command creates multiple breakpoints (e.g.,
1712 breakpoints on overloaded c++ functions).
1714 * The `rbreak' command now accepts a filename specification as part of
1715 its argument, limiting the functions selected by the regex to those
1716 in the specified file.
1718 * Support for remote debugging Windows and SymbianOS shared libraries
1719 from Unix hosts has been improved. Non Windows GDB builds now can
1720 understand target reported file names that follow MS-DOS based file
1721 system semantics, such as file names that include drive letters and
1722 use the backslash character as directory separator. This makes it
1723 possible to transparently use the "set sysroot" and "set
1724 solib-search-path" on Unix hosts to point as host copies of the
1725 target's shared libraries. See the new command "set
1726 target-file-system-kind" described below, and the "Commands to
1727 specify files" section in the user manual for more information.
1731 eval template, expressions...
1732 Convert the values of one or more expressions under the control
1733 of the string template to a command line, and call it.
1735 set target-file-system-kind unix|dos-based|auto
1736 show target-file-system-kind
1737 Set or show the assumed file system kind for target reported file
1740 save breakpoints <filename>
1741 Save all current breakpoint definitions to a file suitable for use
1742 in a later debugging session. To read the saved breakpoint
1743 definitions, use the `source' command.
1745 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1748 info static-tracepoint-markers
1749 Display information about static tracepoint markers in the target.
1751 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1752 Define a static tracepoint by probing a marker at the given
1753 function, line, address, or marker ID.
1757 Enable and disable observer mode.
1759 set may-write-registers on|off
1760 set may-write-memory on|off
1761 set may-insert-breakpoints on|off
1762 set may-insert-tracepoints on|off
1763 set may-insert-fast-tracepoints on|off
1764 set may-interrupt on|off
1765 Set individual permissions for GDB effects on the target. Note that
1766 some of these settings can have undesirable or surprising
1767 consequences, particularly when changed in the middle of a session.
1768 For instance, disabling the writing of memory can prevent
1769 breakpoints from being inserted, cause single-stepping to fail, or
1770 even crash your program, if you disable after breakpoints have been
1771 inserted. However, GDB should not crash.
1773 set record memory-query on|off
1774 show record memory-query
1775 Control whether to stop the inferior if memory changes caused
1776 by an instruction cannot be recorded.
1781 The disassemble command now supports "start,+length" form of two arguments.
1785 ** GDB now provides a new directory location, called the python directory,
1786 where Python scripts written for GDB can be installed. The location
1787 of that directory is <data-directory>/python, where <data-directory>
1788 is the GDB data directory. For more details, see section `Scripting
1789 GDB using Python' in the manual.
1791 ** The GDB Python API now has access to breakpoints, symbols, symbol
1792 tables, program spaces, inferiors, threads and frame's code blocks.
1793 Additionally, GDB Parameters can now be created from the API, and
1794 manipulated via set/show in the CLI.
1796 ** New functions gdb.target_charset, gdb.target_wide_charset,
1797 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1799 ** New exception gdb.GdbError.
1801 ** Pretty-printers are now also looked up in the current program space.
1803 ** Pretty-printers can now be individually enabled and disabled.
1805 ** GDB now looks for names of Python scripts to auto-load in a
1806 special section named `.debug_gdb_scripts', in addition to looking
1807 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1809 * Tracepoint actions were unified with breakpoint commands. In particular,
1810 there are no longer differences in "info break" output for breakpoints and
1811 tracepoints and the "commands" command can be used for both tracepoints and
1812 regular breakpoints.
1816 ARM Symbian arm*-*-symbianelf*
1818 * D language support.
1819 GDB now supports debugging programs written in the D programming
1822 * GDB now supports the extended ptrace interface for PowerPC which is
1823 available since Linux kernel version 2.6.34. This automatically enables
1824 any hardware breakpoints and additional hardware watchpoints available in
1825 the processor. The old ptrace interface exposes just one hardware
1826 watchpoint and no hardware breakpoints.
1828 * GDB is now able to use the Data Value Compare (DVC) register available on
1829 embedded PowerPC processors to implement in hardware simple watchpoint
1830 conditions of the form:
1832 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1834 This works in native GDB running on Linux kernels with the extended ptrace
1835 interface mentioned above.
1837 *** Changes in GDB 7.1
1841 ** Namespace Support
1843 GDB now supports importing of namespaces in C++. This enables the
1844 user to inspect variables from imported namespaces. Support for
1845 namepace aliasing has also been added. So, if a namespace is
1846 aliased in the current scope (e.g. namepace C=A; ) the user can
1847 print variables using the alias (e.g. (gdb) print C::x).
1851 All known bugs relating to the printing of virtual base class were
1852 fixed. It is now possible to call overloaded static methods using a
1857 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1858 and reinterpret_cast<> are now handled by the C++ expression parser.
1862 Xilinx MicroBlaze microblaze-*-*
1867 Xilinx MicroBlaze microblaze
1870 * Multi-program debugging.
1872 GDB now has support for multi-program (a.k.a. multi-executable or
1873 multi-exec) debugging. This allows for debugging multiple inferiors
1874 simultaneously each running a different program under the same GDB
1875 session. See "Debugging Multiple Inferiors and Programs" in the
1876 manual for more information. This implied some user visible changes
1877 in the multi-inferior support. For example, "info inferiors" now
1878 lists inferiors that are not running yet or that have exited
1879 already. See also "New commands" and "New options" below.
1881 * New tracing features
1883 GDB's tracepoint facility now includes several new features:
1885 ** Trace state variables
1887 GDB tracepoints now include support for trace state variables, which
1888 are variables managed by the target agent during a tracing
1889 experiment. They are useful for tracepoints that trigger each
1890 other, so for instance one tracepoint can count hits in a variable,
1891 and then a second tracepoint has a condition that is true when the
1892 count reaches a particular value. Trace state variables share the
1893 $-syntax of GDB convenience variables, and can appear in both
1894 tracepoint actions and condition expressions. Use the "tvariable"
1895 command to create, and "info tvariables" to view; see "Trace State
1896 Variables" in the manual for more detail.
1900 GDB now includes an option for defining fast tracepoints, which
1901 targets may implement more efficiently, such as by installing a jump
1902 into the target agent rather than a trap instruction. The resulting
1903 speedup can be by two orders of magnitude or more, although the
1904 tradeoff is that some program locations on some target architectures
1905 might not allow fast tracepoint installation, for instance if the
1906 instruction to be replaced is shorter than the jump. To request a
1907 fast tracepoint, use the "ftrace" command, with syntax identical to
1908 the regular trace command.
1910 ** Disconnected tracing
1912 It is now possible to detach GDB from the target while it is running
1913 a trace experiment, then reconnect later to see how the experiment
1914 is going. In addition, a new variable disconnected-tracing lets you
1915 tell the target agent whether to continue running a trace if the
1916 connection is lost unexpectedly.
1920 GDB now has the ability to save the trace buffer into a file, and
1921 then use that file as a target, similarly to you can do with
1922 corefiles. You can select trace frames, print data that was
1923 collected in them, and use tstatus to display the state of the
1924 tracing run at the moment that it was saved. To create a trace
1925 file, use "tsave <filename>", and to use it, do "target tfile
1928 ** Circular trace buffer
1930 You can ask the target agent to handle the trace buffer as a
1931 circular buffer, discarding the oldest trace frames to make room for
1932 newer ones, by setting circular-trace-buffer to on. This feature may
1933 not be available for all target agents.
1938 The disassemble command, when invoked with two arguments, now requires
1939 the arguments to be comma-separated.
1942 The info variables command now displays variable definitions. Files
1943 which only declare a variable are not shown.
1946 The source command is now capable of sourcing Python scripts.
1947 This feature is dependent on the debugger being build with Python
1950 Related to this enhancement is also the introduction of a new command
1951 "set script-extension" (see below).
1953 * New commands (for set/show, see "New options" below)
1955 record save [<FILENAME>]
1956 Save a file (in core file format) containing the process record
1957 execution log for replay debugging at a later time.
1959 record restore <FILENAME>
1960 Restore the process record execution log that was saved at an
1961 earlier time, for replay debugging.
1963 add-inferior [-copies <N>] [-exec <FILENAME>]
1966 clone-inferior [-copies <N>] [ID]
1967 Make a new inferior ready to execute the same program another
1968 inferior has loaded.
1973 maint info program-spaces
1974 List the program spaces loaded into GDB.
1976 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1977 show remote interrupt-sequence
1978 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1979 as the sequence to the remote target in order to interrupt the execution.
1980 Ctrl-C is a default. Some system prefers BREAK which is high level of
1981 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1982 Magic SysRq g. It is BREAK signal and character 'g'.
1984 set remote interrupt-on-connect [on | off]
1985 show remote interrupt-on-connect
1986 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1987 remote target when gdb connects to it. This is needed when you debug
1990 set remotebreak [on | off]
1992 Deprecated. Use "set/show remote interrupt-sequence" instead.
1994 tvariable $NAME [ = EXP ]
1995 Create or modify a trace state variable.
1998 List trace state variables and their values.
2000 delete tvariable $NAME ...
2001 Delete one or more trace state variables.
2004 Evaluate the given expressions without collecting anything into the
2005 trace buffer. (Valid in tracepoint actions only.)
2007 ftrace FN / FILE:LINE / *ADDR
2008 Define a fast tracepoint at the given function, line, or address.
2010 * New expression syntax
2012 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2013 GDB now parses 0b101010 identically with 42.
2017 set follow-exec-mode new|same
2018 show follow-exec-mode
2019 Control whether GDB reuses the same inferior across an exec call or
2020 creates a new one. This is useful to be able to restart the old
2021 executable after the inferior having done an exec call.
2023 set default-collect EXPR, ...
2024 show default-collect
2025 Define a list of expressions to be collected at each tracepoint.
2026 This is a useful way to ensure essential items are not overlooked,
2027 such as registers or a critical global variable.
2029 set disconnected-tracing
2030 show disconnected-tracing
2031 If set to 1, the target is instructed to continue tracing if it
2032 loses its connection to GDB. If 0, the target is to stop tracing
2035 set circular-trace-buffer
2036 show circular-trace-buffer
2037 If set to on, the target is instructed to use a circular trace buffer
2038 and discard the oldest trace frames instead of stopping the trace due
2039 to a full trace buffer. If set to off, the trace stops when the buffer
2040 fills up. Some targets may not support this.
2042 set script-extension off|soft|strict
2043 show script-extension
2044 If set to "off", the debugger does not perform any script language
2045 recognition, and all sourced files are assumed to be GDB scripts.
2046 If set to "soft" (the default), files are sourced according to
2047 filename extension, falling back to GDB scripts if the first
2049 If set to "strict", files are sourced according to filename extension.
2051 set ada trust-PAD-over-XVS on|off
2052 show ada trust-PAD-over-XVS
2053 If off, activate a workaround against a bug in the debugging information
2054 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2055 the GCC sources for more information about the GNAT encoding and
2056 PAD types in particular). It is always safe to set this option to
2057 off, but this introduces a slight performance penalty. The default
2060 * Python API Improvements
2062 ** GDB provides the new class gdb.LazyString. This is useful in
2063 some pretty-printing cases. The new method gdb.Value.lazy_string
2064 provides a simple way to create objects of this type.
2066 ** The fields returned by gdb.Type.fields now have an
2067 `is_base_class' attribute.
2069 ** The new method gdb.Type.range returns the range of an array type.
2071 ** The new method gdb.parse_and_eval can be used to parse and
2072 evaluate an expression.
2074 * New remote packets
2077 Define a trace state variable.
2080 Get the current value of a trace state variable.
2083 Set desired tracing behavior upon disconnection.
2086 Set the trace buffer to be linear or circular.
2089 Get data about the tracepoints currently in use.
2093 Process record now works correctly with hardware watchpoints.
2095 Multiple bug fixes have been made to the mips-irix port, making it
2096 much more reliable. In particular:
2097 - Debugging threaded applications is now possible again. Previously,
2098 GDB would hang while starting the program, or while waiting for
2099 the program to stop at a breakpoint.
2100 - Attaching to a running process no longer hangs.
2101 - An error occurring while loading a core file has been fixed.
2102 - Changing the value of the PC register now works again. This fixes
2103 problems observed when using the "jump" command, or when calling
2104 a function from GDB, or even when assigning a new value to $pc.
2105 - With the "finish" and "return" commands, the return value for functions
2106 returning a small array is now correctly printed.
2107 - It is now possible to break on shared library code which gets executed
2108 during a shared library init phase (code executed while executing
2109 their .init section). Previously, the breakpoint would have no effect.
2110 - GDB is now able to backtrace through the signal handler for
2111 non-threaded programs.
2113 PIE (Position Independent Executable) programs debugging is now supported.
2114 This includes debugging execution of PIC (Position Independent Code) shared
2115 libraries although for that, it should be possible to run such libraries as an
2118 *** Changes in GDB 7.0
2120 * GDB now has an interface for JIT compilation. Applications that
2121 dynamically generate code can create symbol files in memory and register
2122 them with GDB. For users, the feature should work transparently, and
2123 for JIT developers, the interface is documented in the GDB manual in the
2124 "JIT Compilation Interface" chapter.
2126 * Tracepoints may now be conditional. The syntax is as for
2127 breakpoints; either an "if" clause appended to the "trace" command,
2128 or the "condition" command is available. GDB sends the condition to
2129 the target for evaluation using the same bytecode format as is used
2130 for tracepoint actions.
2132 * The disassemble command now supports: an optional /r modifier, print the
2133 raw instructions in hex as well as in symbolic form, and an optional /m
2134 modifier to print mixed source+assembly.
2136 * Process record and replay
2138 In a architecture environment that supports ``process record and
2139 replay'', ``process record and replay'' target can record a log of
2140 the process execution, and replay it with both forward and reverse
2143 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2144 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2145 set execution-direction {forward|reverse}, for targets that support
2148 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2149 feature is available with a native GDB running on kernel version
2152 * GDB now has support for multi-byte and wide character sets on the
2153 target. Strings whose character type is wchar_t, char16_t, or
2154 char32_t are now correctly printed. GDB supports wide- and unicode-
2155 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2156 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2157 `printf'. This feature requires iconv to work properly; if your
2158 system does not have a working iconv, GDB can use GNU libiconv. See
2159 the installation instructions for more information.
2161 * GDB now supports automatic retrieval of shared library files from
2162 remote targets. To use this feature, specify a system root that begins
2163 with the `remote:' prefix, either via the `set sysroot' command or via
2164 the `--with-sysroot' configure-time option.
2166 * "info sharedlibrary" now takes an optional regex of libraries to show,
2167 and it now reports if a shared library has no debugging information.
2169 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2170 now complete on file names.
2172 * When completing in expressions, gdb will attempt to limit
2173 completions to allowable structure or union fields, where appropriate.
2174 For instance, consider:
2176 # struct example { int f1; double f2; };
2177 # struct example variable;
2180 If the user types TAB at the end of this command line, the available
2181 completions will be "f1" and "f2".
2183 * Inlined functions are now supported. They show up in backtraces, and
2184 the "step", "next", and "finish" commands handle them automatically.
2186 * GDB now supports the token-splicing (##) and stringification (#)
2187 operators when expanding macros. It also supports variable-arity
2190 * GDB now supports inspecting extra signal information, exported by
2191 the new $_siginfo convenience variable. The feature is currently
2192 implemented on linux ARM, i386 and amd64.
2194 * GDB can now display the VFP floating point registers and NEON vector
2195 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2196 can provide these registers (requires Linux 2.6.30 or later). Remote
2197 and simulator targets may also provide them.
2199 * New remote packets
2202 Search memory for a sequence of bytes.
2205 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2206 operation over reliable transport links. Use of this packet is
2207 controlled by the `set remote noack-packet' command.
2210 Kill the process with the specified process ID. Use this in preference
2211 to `k' when multiprocess protocol extensions are supported.
2214 Obtains additional operating system information
2218 Read or write additional signal information.
2220 * Removed remote protocol undocumented extension
2222 An undocumented extension to the remote protocol's `S' stop reply
2223 packet that permited the stub to pass a process id was removed.
2224 Remote servers should use the `T' stop reply packet instead.
2226 * GDB now supports multiple function calling conventions according to the
2227 DWARF-2 DW_AT_calling_convention function attribute.
2229 * The SH target utilizes the aforementioned change to distinguish between gcc
2230 and Renesas calling convention. It also adds the new CLI commands
2231 `set/show sh calling-convention'.
2233 * GDB can now read compressed debug sections, as produced by GNU gold
2234 with the --compress-debug-sections=zlib flag.
2236 * 64-bit core files are now supported on AIX.
2238 * Thread switching is now supported on Tru64.
2240 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2241 which will be allocated using malloc later in program execution.
2243 * The qXfer:libraries:read remote procotol packet now allows passing a
2244 list of section offsets.
2246 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2247 conditions handling signals delivered during attach or thread creation
2248 have also been fixed.
2250 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2251 From the user's standpoint, all unqualified instances of True and False
2252 are treated as the standard definitions, regardless of context.
2254 * GDB now parses C++ symbol and type names more flexibly. For
2257 template<typename T> class C { };
2260 GDB will now correctly handle all of:
2262 ptype C<char const *>
2263 ptype C<char const*>
2264 ptype C<const char *>
2265 ptype C<const char*>
2267 * New features in the GDB remote stub, gdbserver
2269 - The "--wrapper" command-line argument tells gdbserver to use a
2270 wrapper program to launch programs for debugging.
2272 - On PowerPC and S/390 targets, it is now possible to use a single
2273 gdbserver executable to debug both 32-bit and 64-bit programs.
2274 (This requires gdbserver itself to be built as a 64-bit executable.)
2276 - gdbserver uses the new noack protocol mode for TCP connections to
2277 reduce communications latency, if also supported and enabled in GDB.
2279 - Support for the sparc64-linux-gnu target is now included in
2282 - The amd64-linux build of gdbserver now supports debugging both
2283 32-bit and 64-bit programs.
2285 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2286 now support hardware watchpoints, and will use them automatically
2291 GDB now has support for scripting using Python. Whether this is
2292 available is determined at configure time.
2294 New GDB commands can now be written in Python.
2296 * Ada tasking support
2298 Ada tasks can now be inspected in GDB. The following commands have
2302 Print the list of Ada tasks.
2304 Print detailed information about task number N.
2306 Print the task number of the current task.
2308 Switch the context of debugging to task number N.
2310 * Support for user-defined prefixed commands. The "define" command can
2311 add new commands to existing prefixes, e.g. "target".
2313 * Multi-inferior, multi-process debugging.
2315 GDB now has generalized support for multi-inferior debugging. See
2316 "Debugging Multiple Inferiors" in the manual for more information.
2317 Although availability still depends on target support, the command
2318 set is more uniform now. The GNU/Linux specific multi-forks support
2319 has been migrated to this new framework. This implied some user
2320 visible changes; see "New commands" and also "Removed commands"
2323 * Target descriptions can now describe the target OS ABI. See the
2324 "Target Description Format" section in the user manual for more
2327 * Target descriptions can now describe "compatible" architectures
2328 to indicate that the target can execute applications for a different
2329 architecture in addition to those for the main target architecture.
2330 See the "Target Description Format" section in the user manual for
2333 * Multi-architecture debugging.
2335 GDB now includes general supports for debugging applications on
2336 hybrid systems that use more than one single processor architecture
2337 at the same time. Each such hybrid architecture still requires
2338 specific support to be added. The only hybrid architecture supported
2339 in this version of GDB is the Cell Broadband Engine.
2341 * GDB now supports integrated debugging of Cell/B.E. applications that
2342 use both the PPU and SPU architectures. To enable support for hybrid
2343 Cell/B.E. debugging, you need to configure GDB to support both the
2344 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2345 --enable-targets configure option.
2347 * Non-stop mode debugging.
2349 For some targets, GDB now supports an optional mode of operation in
2350 which you can examine stopped threads while other threads continue
2351 to execute freely. This is referred to as non-stop mode, with the
2352 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2353 section in the user manual for more information.
2355 To be able to support remote non-stop debugging, a remote stub needs
2356 to implement the non-stop mode remote protocol extensions, as
2357 described in the "Remote Non-Stop" section of the user manual. The
2358 GDB remote stub, gdbserver, has been adjusted to support these
2359 extensions on linux targets.
2361 * New commands (for set/show, see "New options" below)
2363 catch syscall [NAME(S) | NUMBER(S)]
2364 Catch system calls. Arguments, which should be names of system
2365 calls or their numbers, mean catch only those syscalls. Without
2366 arguments, every syscall will be caught. When the inferior issues
2367 any of the specified syscalls, GDB will stop and announce the system
2368 call, both when it is called and when its call returns. This
2369 feature is currently available with a native GDB running on the
2370 Linux Kernel, under the following architectures: x86, x86_64,
2371 PowerPC and PowerPC64.
2373 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2375 Search memory for a sequence of bytes.
2377 maint set python print-stack
2378 maint show python print-stack
2379 Show a stack trace when an error is encountered in a Python script.
2382 Invoke CODE by passing it to the Python interpreter.
2387 These allow macros to be defined, undefined, and listed
2391 Show operating system information about processes.
2394 List the inferiors currently under GDB's control.
2397 Switch focus to inferior number NUM.
2400 Detach from inferior number NUM.
2403 Kill inferior number NUM.
2407 set spu stop-on-load
2408 show spu stop-on-load
2409 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2411 set spu auto-flush-cache
2412 show spu auto-flush-cache
2413 Control whether to automatically flush the software-managed cache
2414 during Cell/B.E. debugging.
2416 set sh calling-convention
2417 show sh calling-convention
2418 Control the calling convention used when calling SH target functions.
2421 show debug timestamp
2422 Control display of timestamps with GDB debugging output.
2424 set disassemble-next-line
2425 show disassemble-next-line
2426 Control display of disassembled source lines or instructions when
2429 set remote noack-packet
2430 show remote noack-packet
2431 Set/show the use of remote protocol QStartNoAckMode packet. See above
2432 under "New remote packets."
2434 set remote query-attached-packet
2435 show remote query-attached-packet
2436 Control use of remote protocol `qAttached' (query-attached) packet.
2438 set remote read-siginfo-object
2439 show remote read-siginfo-object
2440 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2443 set remote write-siginfo-object
2444 show remote write-siginfo-object
2445 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2448 set remote reverse-continue
2449 show remote reverse-continue
2450 Control use of remote protocol 'bc' (reverse-continue) packet.
2452 set remote reverse-step
2453 show remote reverse-step
2454 Control use of remote protocol 'bs' (reverse-step) packet.
2456 set displaced-stepping
2457 show displaced-stepping
2458 Control displaced stepping mode. Displaced stepping is a way to
2459 single-step over breakpoints without removing them from the debuggee.
2460 Also known as "out-of-line single-stepping".
2463 show debug displaced
2464 Control display of debugging info for displaced stepping.
2466 maint set internal-error
2467 maint show internal-error
2468 Control what GDB does when an internal error is detected.
2470 maint set internal-warning
2471 maint show internal-warning
2472 Control what GDB does when an internal warning is detected.
2477 Use a wrapper program to launch programs for debugging.
2479 set multiple-symbols (all|ask|cancel)
2480 show multiple-symbols
2481 The value of this variable can be changed to adjust the debugger behavior
2482 when an expression or a breakpoint location contains an ambiguous symbol
2483 name (an overloaded function name, for instance).
2485 set breakpoint always-inserted
2486 show breakpoint always-inserted
2487 Keep breakpoints always inserted in the target, as opposed to inserting
2488 them when resuming the target, and removing them when the target stops.
2489 This option can improve debugger performance on slow remote targets.
2491 set arm fallback-mode (arm|thumb|auto)
2492 show arm fallback-mode
2493 set arm force-mode (arm|thumb|auto)
2495 These commands control how ARM GDB determines whether instructions
2496 are ARM or Thumb. The default for both settings is auto, which uses
2497 the current CPSR value for instructions without symbols; previous
2498 versions of GDB behaved as if "set arm fallback-mode arm".
2500 set disable-randomization
2501 show disable-randomization
2502 Standalone programs run with the virtual address space randomization enabled
2503 by default on some platforms. This option keeps the addresses stable across
2504 multiple debugging sessions.
2508 Control whether other threads are stopped or not when some thread hits
2513 Requests that asynchronous execution is enabled in the target, if available.
2514 In this case, it's possible to resume target in the background, and interact
2515 with GDB while the target is running. "show target-async" displays the
2516 current state of asynchronous execution of the target.
2518 set target-wide-charset
2519 show target-wide-charset
2520 The target-wide-charset is the name of the character set that GDB
2521 uses when printing characters whose type is wchar_t.
2523 set tcp auto-retry (on|off)
2525 set tcp connect-timeout
2526 show tcp connect-timeout
2527 These commands allow GDB to retry failed TCP connections to a remote stub
2528 with a specified timeout period; this is useful if the stub is launched
2529 in parallel with GDB but may not be ready to accept connections immediately.
2531 set libthread-db-search-path
2532 show libthread-db-search-path
2533 Control list of directories which GDB will search for appropriate
2536 set schedule-multiple (on|off)
2537 show schedule-multiple
2538 Allow GDB to resume all threads of all processes or only threads of
2539 the current process.
2543 Use more aggressive caching for accesses to the stack. This improves
2544 performance of remote debugging (particularly backtraces) without
2545 affecting correctness.
2547 set interactive-mode (on|off|auto)
2548 show interactive-mode
2549 Control whether GDB runs in interactive mode (on) or not (off).
2550 When in interactive mode, GDB waits for the user to answer all
2551 queries. Otherwise, GDB does not wait and assumes the default
2552 answer. When set to auto (the default), GDB determines which
2553 mode to use based on the stdin settings.
2558 For program forks, this is replaced by the new more generic `info
2559 inferiors' command. To list checkpoints, you can still use the
2560 `info checkpoints' command, which was an alias for the `info forks'
2564 Replaced by the new `inferior' command. To switch between
2565 checkpoints, you can still use the `restart' command, which was an
2566 alias for the `fork' command.
2569 This is removed, since some targets don't have a notion of
2570 processes. To switch between processes, you can still use the
2571 `inferior' command using GDB's own inferior number.
2574 For program forks, this is replaced by the new more generic `kill
2575 inferior' command. To delete a checkpoint, you can still use the
2576 `delete checkpoint' command, which was an alias for the `delete
2580 For program forks, this is replaced by the new more generic `detach
2581 inferior' command. To detach a checkpoint, you can still use the
2582 `detach checkpoint' command, which was an alias for the `detach
2585 * New native configurations
2587 x86/x86_64 Darwin i[34567]86-*-darwin*
2589 x86_64 MinGW x86_64-*-mingw*
2593 Lattice Mico32 lm32-*
2594 x86 DICOS i[34567]86-*-dicos*
2595 x86_64 DICOS x86_64-*-dicos*
2598 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2599 (mingw32ce) debugging.
2605 These commands were actually not implemented on any target.
2607 *** Changes in GDB 6.8
2609 * New native configurations
2611 NetBSD/hppa hppa*-*netbsd*
2612 Xtensa GNU/Linux xtensa*-*-linux*
2616 NetBSD/hppa hppa*-*-netbsd*
2617 Xtensa GNU/Lunux xtensa*-*-linux*
2619 * Change in command line behavior -- corefiles vs. process ids.
2621 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2622 attaching to process NUMBER fails, GDB no longer attempts to open a
2623 core file named NUMBER. Attaching to a program using the -c option
2624 is no longer supported. Instead, use the '-p' or '--pid' options.
2626 * GDB can now be built as a native debugger for debugging Windows x86
2627 (mingw32) Portable Executable (PE) programs.
2629 * Pending breakpoints no longer change their number when their address
2632 * GDB now supports breakpoints with multiple locations,
2633 including breakpoints on C++ constructors, inside C++ templates,
2634 and in inlined functions.
2636 * GDB's ability to debug optimized code has been improved. GDB more
2637 accurately identifies function bodies and lexical blocks that occupy
2638 more than one contiguous range of addresses.
2640 * Target descriptions can now describe registers for PowerPC.
2642 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2643 registers on PowerPC targets.
2645 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2646 targets even when the libthread_db library is not available.
2648 * The GDB remote stub, gdbserver, now supports the new file transfer
2649 commands (remote put, remote get, and remote delete).
2651 * The GDB remote stub, gdbserver, now supports run and attach in
2652 extended-remote mode.
2654 * hppa*64*-*-hpux11* target broken
2655 The debugger is unable to start a program and fails with the following
2656 error: "Error trying to get information about dynamic linker".
2657 The gdb-6.7 release is also affected.
2659 * GDB now supports the --enable-targets= configure option to allow
2660 building a single GDB executable that supports multiple remote
2661 target architectures.
2663 * GDB now supports debugging C and C++ programs which use the
2664 Decimal Floating Point extension. In addition, the PowerPC target
2665 now has a set of pseudo-registers to inspect decimal float values
2666 stored in two consecutive float registers.
2668 * The -break-insert MI command can optionally create pending
2671 * Improved support for debugging Ada
2672 Many improvements to the Ada language support have been made. These
2674 - Better support for Ada2005 interface types
2675 - Improved handling of arrays and slices in general
2676 - Better support for Taft-amendment types
2677 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2679 - Improved command completion in Ada
2682 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2687 set print frame-arguments (all|scalars|none)
2688 show print frame-arguments
2689 The value of this variable can be changed to control which argument
2690 values should be printed by the debugger when displaying a frame.
2695 Transfer files to and from a remote target, and delete remote files.
2702 Transfer files to and from a remote target, and delete remote files.
2704 * New remote packets
2711 Open, close, read, write, and delete files on the remote system.
2714 Attach to an existing process on the remote system, in extended-remote
2718 Run a new process on the remote system, in extended-remote mode.
2720 *** Changes in GDB 6.7
2722 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2723 bfd, libiberty and opcodes, as revealed by static analysis donated by
2724 Coverity, Inc. (http://scan.coverity.com).
2726 * When looking up multiply-defined global symbols, GDB will now prefer the
2727 symbol definition in the current shared library if it was built using the
2728 -Bsymbolic linker option.
2730 * When the Text User Interface (TUI) is not configured, GDB will now
2731 recognize the -tui command-line option and print a message that the TUI
2734 * The GDB remote stub, gdbserver, now has lower overhead for high
2735 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2737 * GDB for MIPS targets now autodetects whether a remote target provides
2738 32-bit or 64-bit register values.
2740 * Support for C++ member pointers has been improved.
2742 * GDB now understands XML target descriptions, which specify the
2743 target's overall architecture. GDB can read a description from
2744 a local file or over the remote serial protocol.
2746 * Vectors of single-byte data use a new integer type which is not
2747 automatically displayed as character or string data.
2749 * The /s format now works with the print command. It displays
2750 arrays of single-byte integers and pointers to single-byte integers
2753 * Target descriptions can now describe target-specific registers,
2754 for architectures which have implemented the support (currently
2755 only ARM, M68K, and MIPS).
2757 * GDB and the GDB remote stub, gdbserver, now support the XScale
2760 * The GDB remote stub, gdbserver, has been updated to support
2761 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2762 has been rewritten to use the standard GDB remote protocol.
2764 * GDB can now step into C++ functions which are called through thunks.
2766 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2768 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2769 layout. It also supports a TextSeg= and DataSeg= response when only
2770 segment base addresses (rather than offsets) are available.
2772 * The /i format now outputs any trailing branch delay slot instructions
2773 immediately following the last instruction within the count specified.
2775 * The GDB remote protocol "T" stop reply packet now supports a
2776 "library" response. Combined with the new "qXfer:libraries:read"
2777 packet, this response allows GDB to debug shared libraries on targets
2778 where the operating system manages the list of loaded libraries (e.g.
2779 Windows and SymbianOS).
2781 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2782 (DLLs) on Windows and Windows CE targets.
2784 * GDB now supports a faster verification that a .debug file matches its binary
2785 according to its build-id signature, if the signature is present.
2791 Enable or disable hardware flow control (RTS/CTS) on the serial port
2792 when debugging using remote targets.
2794 set mem inaccessible-by-default
2795 show mem inaccessible-by-default
2796 If the target supplies a memory map, for instance via the remote
2797 protocol's "qXfer:memory-map:read" packet, setting this variable
2798 prevents GDB from accessing memory outside the memory map. This
2799 is useful for targets with memory mapped registers or which react
2800 badly to accesses of unmapped address space.
2802 set breakpoint auto-hw
2803 show breakpoint auto-hw
2804 If the target supplies a memory map, for instance via the remote
2805 protocol's "qXfer:memory-map:read" packet, setting this variable
2806 lets GDB use hardware breakpoints automatically for memory regions
2807 where it can not use software breakpoints. This covers both the
2808 "break" command and internal breakpoints used for other commands
2809 including "next" and "finish".
2812 catch exception unhandled
2813 Stop the program execution when Ada exceptions are raised.
2816 Stop the program execution when an Ada assertion failed.
2820 Set an alternate system root for target files. This is a more
2821 general version of "set solib-absolute-prefix", which is now
2822 an alias to "set sysroot".
2825 Provide extended SPU facility status information. This set of
2826 commands is available only when debugging the Cell/B.E. SPU
2829 * New native configurations
2831 OpenBSD/sh sh*-*openbsd*
2834 unset tdesc filename
2836 Use the specified local file as an XML target description, and do
2837 not query the target for its built-in description.
2841 OpenBSD/sh sh*-*-openbsd*
2842 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2843 Toshiba Media Processor mep-elf
2845 * New remote packets
2848 Ignore the specified signals; pass them directly to the debugged program
2849 without stopping other threads or reporting them to GDB.
2851 qXfer:features:read:
2852 Read an XML target description from the target, which describes its
2857 Read or write contents of an spufs file on the target system. These
2858 packets are available only on the Cell/B.E. SPU architecture.
2860 qXfer:libraries:read:
2861 Report the loaded shared libraries. Combined with new "T" packet
2862 response, this packet allows GDB to debug shared libraries on
2863 targets where the operating system manages the list of loaded
2864 libraries (e.g. Windows and SymbianOS).
2868 Support for these obsolete configurations has been removed.
2876 i[34567]86-*-lynxos*
2877 i[34567]86-*-netware*
2878 i[34567]86-*-sco3.2v5*
2879 i[34567]86-*-sco3.2v4*
2881 i[34567]86-*-sysv4.2*
2884 i[34567]86-*-unixware2*
2885 i[34567]86-*-unixware*
2894 * Other removed features
2901 Various m68k-only ROM monitors.
2908 Various Renesas ROM monitors and debugging interfaces for SH and
2913 Support for a Macraigor serial interface to on-chip debugging.
2914 GDB does not directly support the newer parallel or USB
2919 A debug information format. The predecessor to DWARF 2 and
2920 DWARF 3, which are still supported.
2922 Support for the HP aCC compiler on HP-UX/PA-RISC
2924 SOM-encapsulated symbolic debugging information, automatic
2925 invocation of pxdb, and the aCC custom C++ ABI. This does not
2926 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2927 with aCC can still be debugged on an assembly level.
2929 MIPS ".pdr" sections
2931 A MIPS-specific format used to describe stack frame layout
2932 in debugging information.
2936 GDB could work with an older version of Guile to debug
2937 the interpreter and Scheme programs running in it.
2939 set mips stack-arg-size
2940 set mips saved-gpreg-size
2942 Use "set mips abi" to control parameter passing for MIPS.
2944 *** Changes in GDB 6.6
2949 Cell Broadband Engine SPU spu-elf
2951 * GDB can now be configured as a cross-debugger targeting native Windows
2952 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2953 running on a Windows system over TCP/IP to debug Windows programs.
2955 * The GDB remote stub, gdbserver, has been updated to support Windows and
2956 Cygwin debugging. Both single-threaded and multi-threaded programs are
2959 * The "set trust-readonly-sections" command works again. This command was
2960 broken in GDB 6.3, 6.4, and 6.5.
2962 * The "load" command now supports writing to flash memory, if the remote
2963 stub provides the required support.
2965 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2966 longer requires symbolic debug information (e.g. DWARF-2).
2971 unset substitute-path
2972 show substitute-path
2973 Manage a list of substitution rules that GDB uses to rewrite the name
2974 of the directories where the sources are located. This can be useful
2975 for instance when the sources were moved to a different location
2976 between compilation and debugging.
2980 Print each CLI command as it is executed. Each command is prefixed with
2981 a number of `+' symbols representing the nesting depth.
2982 The source command now has a `-v' option to enable the same feature.
2986 The ARM Demon monitor support (RDP protocol, "target rdp").
2988 Kernel Object Display, an embedded debugging feature which only worked with
2989 an obsolete version of Cisco IOS.
2991 The 'set download-write-size' and 'show download-write-size' commands.
2993 * New remote packets
2996 Tell a stub about GDB client features, and request remote target features.
2997 The first feature implemented is PacketSize, which allows the target to
2998 specify the size of packets it can handle - to minimize the number of
2999 packets required and improve performance when connected to a remote
3003 Fetch an OS auxilliary vector from the remote stub. This packet is a
3004 more efficient replacement for qPart:auxv:read.
3006 qXfer:memory-map:read:
3007 Fetch a memory map from the remote stub, including information about
3008 RAM, ROM, and flash memory devices.
3013 Erase and program a flash memory device.
3015 * Removed remote packets
3018 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3019 used it, and only gdbserver implemented it.
3021 *** Changes in GDB 6.5
3025 Renesas M32C/M16C m32c-elf
3027 Morpho Technologies ms1 ms1-elf
3031 init-if-undefined Initialize a convenience variable, but
3032 only if it doesn't already have a value.
3034 The following commands are presently only implemented for native GNU/Linux:
3036 checkpoint Save a snapshot of the program state.
3038 restart <n> Return the program state to a
3039 previously saved state.
3041 info checkpoints List currently saved checkpoints.
3043 delete-checkpoint <n> Delete a previously saved checkpoint.
3045 set|show detach-on-fork Tell gdb whether to detach from a newly
3046 forked process, or to keep debugging it.
3048 info forks List forks of the user program that
3049 are available to be debugged.
3051 fork <n> Switch to debugging one of several
3052 forks of the user program that are
3053 available to be debugged.
3055 delete-fork <n> Delete a fork from the list of forks
3056 that are available to be debugged (and
3057 kill the forked process).
3059 detach-fork <n> Delete a fork from the list of forks
3060 that are available to be debugged (and
3061 allow the process to continue).
3065 Morpho Technologies ms2 ms1-elf
3067 * Improved Windows host support
3069 GDB now builds as a cross debugger hosted on i686-mingw32, including
3070 native console support, and remote communications using either
3071 network sockets or serial ports.
3073 * Improved Modula-2 language support
3075 GDB can now print most types in the Modula-2 syntax. This includes:
3076 basic types, set types, record types, enumerated types, range types,
3077 pointer types and ARRAY types. Procedure var parameters are correctly
3078 printed and hexadecimal addresses and character constants are also
3079 written in the Modula-2 syntax. Best results can be obtained by using
3080 GNU Modula-2 together with the -gdwarf-2 command line option.
3084 The ARM rdi-share module.
3086 The Netware NLM debug server.
3088 *** Changes in GDB 6.4
3090 * New native configurations
3092 OpenBSD/arm arm*-*-openbsd*
3093 OpenBSD/mips64 mips64-*-openbsd*
3097 Morpho Technologies ms1 ms1-elf
3099 * New command line options
3101 --batch-silent As for --batch, but totally silent.
3102 --return-child-result The debugger will exist with the same value
3103 the child (debugged) program exited with.
3104 --eval-command COMMAND, -ex COMMAND
3105 Execute a single GDB CLI command. This may be
3106 specified multiple times and in conjunction
3107 with the --command (-x) option.
3109 * Deprecated commands removed
3111 The following commands, that were deprecated in 2000, have been
3115 set|show arm disassembly-flavor set|show arm disassembler
3116 othernames set arm disassembler
3117 set|show remotedebug set|show debug remote
3118 set|show archdebug set|show debug arch
3119 set|show eventdebug set|show debug event
3122 * New BSD user-level threads support
3124 It is now possible to debug programs using the user-level threads
3125 library on OpenBSD and FreeBSD. Currently supported (target)
3128 FreeBSD/amd64 x86_64-*-freebsd*
3129 FreeBSD/i386 i386-*-freebsd*
3130 OpenBSD/i386 i386-*-openbsd*
3132 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3133 are not yet supported.
3135 * New support for Matsushita MN10300 w/sim added
3136 (Work in progress). mn10300-elf.
3138 * REMOVED configurations and files
3140 VxWorks and the XDR protocol *-*-vxworks
3141 Motorola MCORE mcore-*-*
3142 National Semiconductor NS32000 ns32k-*-*
3144 * New "set print array-indexes" command
3146 After turning this setting "on", GDB prints the index of each element
3147 when displaying arrays. The default is "off" to preserve the previous
3150 * VAX floating point support
3152 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3154 * User-defined command support
3156 In addition to using $arg0..$arg9 for argument passing, it is now possible
3157 to use $argc to determine now many arguments have been passed. See the
3158 section on user-defined commands in the user manual for more information.
3160 *** Changes in GDB 6.3:
3162 * New command line option
3164 GDB now accepts -l followed by a number to set the timeout for remote
3167 * GDB works with GCC -feliminate-dwarf2-dups
3169 GDB now supports a more compact representation of DWARF-2 debug
3170 information using DW_FORM_ref_addr references. These are produced
3171 by GCC with the option -feliminate-dwarf2-dups and also by some
3172 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3173 to use -feliminate-dwarf2-dups.
3175 * Internationalization
3177 When supported by the host system, GDB will be built with
3178 internationalization (libintl). The task of marking up the sources is
3179 continued, we're looking forward to our first translation.
3183 Initial support for debugging programs compiled with the GNAT
3184 implementation of the Ada programming language has been integrated
3185 into GDB. In this release, support is limited to expression evaluation.
3187 * New native configurations
3189 GNU/Linux/m32r m32r-*-linux-gnu
3193 GDB's remote protocol now includes support for the 'p' packet. This
3194 packet is used to fetch individual registers from a remote inferior.
3196 * END-OF-LIFE registers[] compatibility module
3198 GDB's internal register infrastructure has been completely rewritten.
3199 The new infrastructure making possible the implementation of key new
3200 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3203 GDB 6.3 will be the last release to include the the registers[]
3204 compatibility module that allowed out-of-date configurations to
3205 continue to work. This change directly impacts the following
3215 powerpc bdm protocol
3217 Unless there is activity to revive these configurations, they will be
3218 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3220 * OBSOLETE configurations and files
3222 Configurations that have been declared obsolete in this release have
3223 been commented out. Unless there is activity to revive these
3224 configurations, the next release of GDB will have their sources
3225 permanently REMOVED.
3234 *** Changes in GDB 6.2.1:
3236 * MIPS `break main; run' gave an heuristic-fence-post warning
3238 When attempting to run even a simple program, a warning about
3239 heuristic-fence-post being hit would be reported. This problem has
3242 * MIPS IRIX 'long double' crashed GDB
3244 When examining a long double variable, GDB would get a segmentation
3245 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3246 IRIX long double values).
3250 A bug in the VAX stack code was causing problems with the "next"
3251 command. This problem has been fixed.
3253 *** Changes in GDB 6.2:
3255 * Fix for ``many threads''
3257 On GNU/Linux systems that use the NPTL threads library, a program
3258 rapidly creating and deleting threads would confuse GDB leading to the
3261 ptrace: No such process.
3262 thread_db_get_info: cannot get thread info: generic error
3264 This problem has been fixed.
3266 * "-async" and "-noasync" options removed.
3268 Support for the broken "-noasync" option has been removed (it caused
3271 * New ``start'' command.
3273 This command runs the program until the begining of the main procedure.
3275 * New BSD Kernel Data Access Library (libkvm) interface
3277 Using ``target kvm'' it is now possible to debug kernel core dumps and
3278 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3279 platforms. Currently supported (native-only) configurations are:
3281 FreeBSD/amd64 x86_64-*-freebsd*
3282 FreeBSD/i386 i?86-*-freebsd*
3283 NetBSD/i386 i?86-*-netbsd*
3284 NetBSD/m68k m68*-*-netbsd*
3285 NetBSD/sparc sparc-*-netbsd*
3286 OpenBSD/amd64 x86_64-*-openbsd*
3287 OpenBSD/i386 i?86-*-openbsd*
3288 OpenBSD/m68k m68*-openbsd*
3289 OpenBSD/sparc sparc-*-openbsd*
3291 * Signal trampoline code overhauled
3293 Many generic problems with GDB's signal handling code have been fixed.
3294 These include: backtraces through non-contiguous stacks; recognition
3295 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3296 call; backtrace through a signal trampoline; step into and out of
3297 signal handlers; and single-stepping in the signal trampoline.
3299 Please note that kernel bugs are a limiting factor here. These
3300 features have been shown to work on an s390 GNU/Linux system that
3301 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3303 * Cygwin support for DWARF 2 added.
3305 * New native configurations
3307 GNU/Linux/hppa hppa*-*-linux*
3308 OpenBSD/hppa hppa*-*-openbsd*
3309 OpenBSD/m68k m68*-*-openbsd*
3310 OpenBSD/m88k m88*-*-openbsd*
3311 OpenBSD/powerpc powerpc-*-openbsd*
3312 NetBSD/vax vax-*-netbsd*
3313 OpenBSD/vax vax-*-openbsd*
3315 * END-OF-LIFE frame compatibility module
3317 GDB's internal frame infrastructure has been completely rewritten.
3318 The new infrastructure making it possible to support key new features
3319 including DWARF 2 Call Frame Information. To aid in the task of
3320 migrating old configurations to this new infrastructure, a
3321 compatibility module, that allowed old configurations to continue to
3322 work, was also included.
3324 GDB 6.2 will be the last release to include this frame compatibility
3325 module. This change directly impacts the following configurations:
3335 Unless there is activity to revive these configurations, they will be
3336 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3338 * REMOVED configurations and files
3340 Sun 3, running SunOS 3 m68*-*-sunos3*
3341 Sun 3, running SunOS 4 m68*-*-sunos4*
3342 Sun 2, running SunOS 3 m68000-*-sunos3*
3343 Sun 2, running SunOS 4 m68000-*-sunos4*
3344 Motorola 680x0 running LynxOS m68*-*-lynxos*
3345 AT&T 3b1/Unix pc m68*-att-*
3346 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3347 decstation mips-dec-* mips-little-*
3348 riscos mips-*-riscos* mips-*-sysv*
3349 sonymips mips-sony-*
3350 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3352 *** Changes in GDB 6.1.1:
3354 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3356 The TUI (Text-mode User Interface) is now built as part of a default
3357 GDB configuration. It is enabled by either selecting the TUI with the
3358 command line option "-i=tui" or by running the separate "gdbtui"
3359 program. For more information on the TUI, see the manual "Debugging
3362 * Pending breakpoint support (also included in GDB 6.1)
3364 Support has been added to allow you to specify breakpoints in shared
3365 libraries that have not yet been loaded. If a breakpoint location
3366 cannot be found, and the "breakpoint pending" option is set to auto,
3367 GDB queries you if you wish to make the breakpoint pending on a future
3368 shared-library load. If and when GDB resolves the breakpoint symbol,
3369 the pending breakpoint is removed as one or more regular breakpoints
3372 Pending breakpoints are very useful for GCJ Java debugging.
3374 * Fixed ISO-C build problems
3376 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3377 non ISO-C code that stopped them being built using a more strict ISO-C
3378 compiler (e.g., IBM's C compiler).
3380 * Fixed build problem on IRIX 5
3382 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3383 wasn't able to compile compile on an IRIX 5 system.
3385 * Added execute permission to gdb/gdbserver/configure
3387 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3388 permission. This bug would cause configure to fail on a number of
3389 systems (Solaris, IRIX). Ref: server/519.
3391 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3393 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3394 has been updated to use constant array sizes.
3396 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3398 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3399 its generated DWARF Call Frame Info. This encoding was causing GDB to
3400 panic, that panic has been fixed. Ref: gdb/1628.
3402 * Fixed a problem when examining parameters in shared library code.
3404 When examining parameters in optimized shared library code generated
3405 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3406 not available''. GDB now correctly displays the variable's value.
3408 *** Changes in GDB 6.1:
3410 * Removed --with-mmalloc
3412 Support for the mmalloc memory manager has been removed, as it
3413 conflicted with the internal gdb byte cache.
3415 * Changes in AMD64 configurations
3417 The AMD64 target now includes the %cs and %ss registers. As a result
3418 the AMD64 remote protocol has changed; this affects the floating-point
3419 and SSE registers. If you rely on those registers for your debugging,
3420 you should upgrade gdbserver on the remote side.
3422 * Revised SPARC target
3424 The SPARC target has been completely revised, incorporating the
3425 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3426 support for LynxOS and SunOS 4 has been dropped. Calling functions
3427 from within GDB on operating systems with a non-executable stack
3428 (Solaris, OpenBSD) now works.
3432 GDB has a new C++ demangler which does a better job on the mangled
3433 names generated by current versions of g++. It also runs faster, so
3434 with this and other changes gdb should now start faster on large C++
3437 * DWARF 2 Location Expressions
3439 GDB support for location expressions has been extended to support function
3440 arguments and frame bases. Older versions of GDB could crash when they
3443 * C++ nested types and namespaces
3445 GDB's support for nested types and namespaces in C++ has been
3446 improved, especially if you use the DWARF 2 debugging format. (This
3447 is the default for recent versions of GCC on most platforms.)
3448 Specifically, if you have a class "Inner" defined within a class or
3449 namespace "Outer", then GDB realizes that the class's name is
3450 "Outer::Inner", not simply "Inner". This should greatly reduce the
3451 frequency of complaints about not finding RTTI symbols. In addition,
3452 if you are stopped at inside of a function defined within a namespace,
3453 GDB modifies its name lookup accordingly.
3455 * New native configurations
3457 NetBSD/amd64 x86_64-*-netbsd*
3458 OpenBSD/amd64 x86_64-*-openbsd*
3459 OpenBSD/alpha alpha*-*-openbsd*
3460 OpenBSD/sparc sparc-*-openbsd*
3461 OpenBSD/sparc64 sparc64-*-openbsd*
3463 * New debugging protocols
3465 M32R with SDI protocol m32r-*-elf*
3467 * "set prompt-escape-char" command deleted.
3469 The command "set prompt-escape-char" has been deleted. This command,
3470 and its very obscure effet on GDB's prompt, was never documented,
3471 tested, nor mentioned in the NEWS file.
3473 * OBSOLETE configurations and files
3475 Configurations that have been declared obsolete in this release have
3476 been commented out. Unless there is activity to revive these
3477 configurations, the next release of GDB will have their sources
3478 permanently REMOVED.
3480 Sun 3, running SunOS 3 m68*-*-sunos3*
3481 Sun 3, running SunOS 4 m68*-*-sunos4*
3482 Sun 2, running SunOS 3 m68000-*-sunos3*
3483 Sun 2, running SunOS 4 m68000-*-sunos4*
3484 Motorola 680x0 running LynxOS m68*-*-lynxos*
3485 AT&T 3b1/Unix pc m68*-att-*
3486 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3487 decstation mips-dec-* mips-little-*
3488 riscos mips-*-riscos* mips-*-sysv*
3489 sonymips mips-sony-*
3490 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3492 * REMOVED configurations and files
3494 SGI Irix-4.x mips-sgi-irix4 or iris4
3495 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3496 Z8000 simulator z8k-zilog-none or z8ksim
3497 Matsushita MN10200 w/simulator mn10200-*-*
3498 H8/500 simulator h8500-hitachi-hms or h8500hms
3499 HP/PA running BSD hppa*-*-bsd*
3500 HP/PA running OSF/1 hppa*-*-osf*
3501 HP/PA Pro target hppa*-*-pro*
3502 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3503 386BSD i[3456]86-*-bsd*
3504 Sequent family i[3456]86-sequent-sysv4*
3505 i[3456]86-sequent-sysv*
3506 i[3456]86-sequent-bsd*
3507 SPARC running LynxOS sparc-*-lynxos*
3508 SPARC running SunOS 4 sparc-*-sunos4*
3509 Tsqware Sparclet sparclet-*-*
3510 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3512 *** Changes in GDB 6.0:
3516 Support for debugging the Objective-C programming language has been
3517 integrated into GDB.
3519 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3521 DWARF 2's Call Frame Information makes available compiler generated
3522 information that more exactly describes the program's run-time stack.
3523 By using this information, GDB is able to provide more robust stack
3526 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3527 have been updated to use a new backtrace mechanism which includes
3528 DWARF 2 CFI support.
3532 GDB's remote protocol has been extended to include support for hosted
3533 file I/O (where the remote target uses GDB's file system). See GDB's
3534 remote protocol documentation for details.
3536 * All targets using the new architecture framework.
3538 All of GDB's targets have been updated to use the new internal
3539 architecture framework. The way is now open for future GDB releases
3540 to include cross-architecture native debugging support (i386 on amd64,
3543 * GNU/Linux's Thread Local Storage (TLS)
3545 GDB now includes support for for the GNU/Linux implementation of
3546 per-thread variables.
3548 * GNU/Linux's Native POSIX Thread Library (NPTL)
3550 GDB's thread code has been updated to work with either the new
3551 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3553 * Separate debug info.
3555 GDB, in conjunction with BINUTILS, now supports a mechanism for
3556 automatically loading debug information from a separate file. Instead
3557 of shipping full debug and non-debug versions of system libraries,
3558 system integrators can now instead ship just the stripped libraries
3559 and optional debug files.
3561 * DWARF 2 Location Expressions
3563 DWARF 2 Location Expressions allow the compiler to more completely
3564 describe the location of variables (even in optimized code) to the
3567 GDB now includes preliminary support for location expressions (support
3568 for DW_OP_piece is still missing).
3572 A number of long standing bugs that caused GDB to die while starting a
3573 Java application have been fixed. GDB's Java support is now
3574 considered "useable".
3576 * GNU/Linux support for fork, vfork, and exec.
3578 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3579 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3582 * GDB supports logging output to a file
3584 There are two new commands, "set logging" and "show logging", which can be
3585 used to capture GDB's output to a file.
3587 * The meaning of "detach" has changed for gdbserver
3589 The "detach" command will now resume the application, as documented. To
3590 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3593 * d10v, m68hc11 `regs' command deprecated
3595 The `info registers' command has been updated so that it displays the
3596 registers using a format identical to the old `regs' command.
3600 A new command, "maint set profile on/off", has been added. This command can
3601 be used to enable or disable profiling while running GDB, to profile a
3602 session or a set of commands. In addition there is a new configure switch,
3603 "--enable-profiling", which will cause GDB to be compiled with profiling
3604 data, for more informative profiling results.
3606 * Default MI syntax changed to "mi2".
3608 The default MI (machine interface) syntax, enabled by the command line
3609 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3610 "mi1", can be enabled by specifying the option "-i=mi1".
3612 Support for the original "mi0" syntax (included in GDB 5.0) has been
3615 Fix for gdb/192: removed extraneous space when displaying frame level.
3616 Fix for gdb/672: update changelist is now output in mi list format.
3617 Fix for gdb/702: a -var-assign that updates the value now shows up
3618 in a subsequent -var-update.
3620 * New native configurations.
3622 FreeBSD/amd64 x86_64-*-freebsd*
3624 * Multi-arched targets.
3626 HP/PA HPUX11 hppa*-*-hpux*
3627 Renesas M32R/D w/simulator m32r-*-elf*
3629 * OBSOLETE configurations and files
3631 Configurations that have been declared obsolete in this release have
3632 been commented out. Unless there is activity to revive these
3633 configurations, the next release of GDB will have their sources
3634 permanently REMOVED.
3636 Z8000 simulator z8k-zilog-none or z8ksim
3637 Matsushita MN10200 w/simulator mn10200-*-*
3638 H8/500 simulator h8500-hitachi-hms or h8500hms
3639 HP/PA running BSD hppa*-*-bsd*
3640 HP/PA running OSF/1 hppa*-*-osf*
3641 HP/PA Pro target hppa*-*-pro*
3642 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3643 Sequent family i[3456]86-sequent-sysv4*
3644 i[3456]86-sequent-sysv*
3645 i[3456]86-sequent-bsd*
3646 Tsqware Sparclet sparclet-*-*
3647 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3649 * REMOVED configurations and files
3652 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3653 IBM AIX PS/2 i[3456]86-*-aix
3654 i386 running Mach 3.0 i[3456]86-*-mach3*
3655 i386 running Mach i[3456]86-*-mach*
3656 i386 running OSF/1 i[3456]86-*osf1mk*
3657 HP/Apollo 68k Family m68*-apollo*-sysv*,
3659 m68*-hp-bsd*, m68*-hp-hpux*
3660 Argonaut Risc Chip (ARC) arc-*-*
3661 Mitsubishi D30V d30v-*-*
3662 Fujitsu FR30 fr30-*-elf*
3663 OS/9000 i[34]86-*-os9k
3664 I960 with MON960 i960-*-coff
3666 * MIPS $fp behavior changed
3668 The convenience variable $fp, for the MIPS, now consistently returns
3669 the address of the current frame's base. Previously, depending on the
3670 context, $fp could refer to either $sp or the current frame's base
3671 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3672 The GNU Source-Level Debugger''.
3674 *** Changes in GDB 5.3:
3676 * GNU/Linux shared library multi-threaded performance improved.
3678 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3679 `/proc', in preference to `ptrace' for memory reads. This may result
3680 in an improvement in the start-up time of multi-threaded, shared
3681 library applications when run under GDB. One GDB user writes: ``loads
3682 shared libs like mad''.
3684 * ``gdbserver'' now supports multi-threaded applications on some targets
3686 Support for debugging multi-threaded applications which use
3687 the GNU/Linux LinuxThreads package has been added for
3688 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3689 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3691 * GDB now supports C/C++ preprocessor macros.
3693 GDB now expands preprocessor macro invocations in C/C++ expressions,
3694 and provides various commands for showing macro definitions and how
3697 The new command `macro expand EXPRESSION' expands any macro
3698 invocations in expression, and shows the result.
3700 The new command `show macro MACRO-NAME' shows the definition of the
3701 macro named MACRO-NAME, and where it was defined.
3703 Most compilers don't include information about macros in the debugging
3704 information by default. In GCC 3.1, for example, you need to compile
3705 your program with the options `-gdwarf-2 -g3'. If the macro
3706 information is present in the executable, GDB will read it.
3708 * Multi-arched targets.
3710 DEC Alpha (partial) alpha*-*-*
3711 DEC VAX (partial) vax-*-*
3713 National Semiconductor NS32000 (partial) ns32k-*-*
3714 Motorola 68000 (partial) m68k-*-*
3715 Motorola MCORE mcore-*-*
3719 Fujitsu FRV architecture added by Red Hat frv*-*-*
3722 * New native configurations
3724 Alpha NetBSD alpha*-*-netbsd*
3725 SH NetBSD sh*-*-netbsdelf*
3726 MIPS NetBSD mips*-*-netbsd*
3727 UltraSPARC NetBSD sparc64-*-netbsd*
3729 * OBSOLETE configurations and files
3731 Configurations that have been declared obsolete in this release have
3732 been commented out. Unless there is activity to revive these
3733 configurations, the next release of GDB will have their sources
3734 permanently REMOVED.
3736 Mitsubishi D30V d30v-*-*
3737 OS/9000 i[34]86-*-os9k
3738 IBM AIX PS/2 i[3456]86-*-aix
3739 Fujitsu FR30 fr30-*-elf*
3740 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3741 Argonaut Risc Chip (ARC) arc-*-*
3742 i386 running Mach 3.0 i[3456]86-*-mach3*
3743 i386 running Mach i[3456]86-*-mach*
3744 i386 running OSF/1 i[3456]86-*osf1mk*
3745 HP/Apollo 68k Family m68*-apollo*-sysv*,
3747 m68*-hp-bsd*, m68*-hp-hpux*
3748 I960 with MON960 i960-*-coff
3750 * OBSOLETE languages
3752 CHILL, a Pascal like language used by telecommunications companies.
3754 * REMOVED configurations and files
3756 AMD 29k family via UDI a29k-amd-udi, udi29k
3757 A29K VxWorks a29k-*-vxworks
3758 AMD 29000 embedded, using EBMON a29k-none-none
3759 AMD 29000 embedded with COFF a29k-none-coff
3760 AMD 29000 embedded with a.out a29k-none-aout
3762 testsuite/gdb.hp/gdb.threads-hp/ directory
3764 * New command "set max-user-call-depth <nnn>"
3766 This command allows the user to limit the call depth of user-defined
3767 commands. The default is 1024.
3769 * Changes in FreeBSD/i386 native debugging.
3771 Support for the "generate-core-file" has been added.
3773 * New commands "dump", "append", and "restore".
3775 These commands allow data to be copied from target memory
3776 to a bfd-format or binary file (dump and append), and back
3777 from a file into memory (restore).
3779 * Improved "next/step" support on multi-processor Alpha Tru64.
3781 The previous single-step mechanism could cause unpredictable problems,
3782 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3783 of a software single-step mechanism prevents this.
3785 *** Changes in GDB 5.2.1:
3793 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3794 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3795 Fix, by Joel Brobecker imported from mainline.
3797 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3798 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3799 Fix, by Fred Fish, imported from mainline.
3801 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3802 Surprisingly enough, it works now.
3803 By Michal Ludvig, imported from mainline.
3805 i386 hardware watchpoint support:
3806 avoid misses on second run for some targets.
3807 By Pierre Muller, imported from mainline.
3809 *** Changes in GDB 5.2:
3811 * New command "set trust-readonly-sections on[off]".
3813 This command is a hint that tells gdb that read-only sections
3814 really are read-only (ie. that their contents will not change).
3815 In this mode, gdb will go to the object file rather than the
3816 target to read memory from read-only sections (such as ".text").
3817 This can be a significant performance improvement on some
3818 (notably embedded) targets.
3820 * New command "generate-core-file" (or "gcore").
3822 This new gdb command allows the user to drop a core file of the child
3823 process state at any time. So far it's been implemented only for
3824 GNU/Linux and Solaris, but should be relatively easily ported to other
3825 hosts. Argument is core file name (defaults to core.<pid>).
3827 * New command line option
3829 GDB now accepts --pid or -p followed by a process id.
3831 * Change in command line behavior -- corefiles vs. process ids.
3833 There is a subtle behavior in the way in which GDB handles
3834 command line arguments. The first non-flag argument is always
3835 a program to debug, but the second non-flag argument may either
3836 be a corefile or a process id. Previously, GDB would attempt to
3837 open the second argument as a corefile, and if that failed, would
3838 issue a superfluous error message and then attempt to attach it as
3839 a process. Now, if the second argument begins with a non-digit,
3840 it will be treated as a corefile. If it begins with a digit,
3841 GDB will attempt to attach it as a process, and if no such process
3842 is found, will then attempt to open it as a corefile.
3844 * Changes in ARM configurations.
3846 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3847 configuration is fully multi-arch.
3849 * New native configurations
3851 ARM NetBSD arm*-*-netbsd*
3852 x86 OpenBSD i[3456]86-*-openbsd*
3853 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3854 Sparc64 running FreeBSD sparc64-*-freebsd*
3858 Sanyo XStormy16 xstormy16-elf
3860 * OBSOLETE configurations and files
3862 Configurations that have been declared obsolete in this release have
3863 been commented out. Unless there is activity to revive these
3864 configurations, the next release of GDB will have their sources
3865 permanently REMOVED.
3867 AMD 29k family via UDI a29k-amd-udi, udi29k
3868 A29K VxWorks a29k-*-vxworks
3869 AMD 29000 embedded, using EBMON a29k-none-none
3870 AMD 29000 embedded with COFF a29k-none-coff
3871 AMD 29000 embedded with a.out a29k-none-aout
3873 testsuite/gdb.hp/gdb.threads-hp/ directory
3875 * REMOVED configurations and files
3877 TI TMS320C80 tic80-*-*
3879 PowerPC Solaris powerpcle-*-solaris*
3880 PowerPC Windows NT powerpcle-*-cygwin32
3881 PowerPC Netware powerpc-*-netware*
3882 Harris/CXUX m88k m88*-harris-cxux*
3883 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3884 ns32k-utek-sysv* ns32k-utek-*
3885 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3886 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3887 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3888 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3889 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3891 * Changes to command line processing
3893 The new `--args' feature can be used to specify command-line arguments
3894 for the inferior from gdb's command line.
3896 * Changes to key bindings
3898 There is a new `operate-and-get-next' function bound to `C-o'.
3900 *** Changes in GDB 5.1.1
3902 Fix compile problem on DJGPP.
3904 Fix a problem with floating-point registers on the i386 being
3907 Fix to stop GDB crashing on .debug_str debug info.
3909 Numerous documentation fixes.
3911 Numerous testsuite fixes.
3913 *** Changes in GDB 5.1:
3915 * New native configurations
3917 Alpha FreeBSD alpha*-*-freebsd*
3918 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3919 MIPS GNU/Linux mips*-*-linux*
3920 MIPS SGI Irix 6.x mips*-sgi-irix6*
3921 ia64 AIX ia64-*-aix*
3922 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3926 Motorola 68HC11 and 68HC12 m68hc11-elf
3928 UltraSparc running GNU/Linux sparc64-*-linux*
3930 * OBSOLETE configurations and files
3932 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3933 Harris/CXUX m88k m88*-harris-cxux*
3934 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3935 ns32k-utek-sysv* ns32k-utek-*
3936 TI TMS320C80 tic80-*-*
3938 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3939 PowerPC Solaris powerpcle-*-solaris*
3940 PowerPC Windows NT powerpcle-*-cygwin32
3941 PowerPC Netware powerpc-*-netware*
3942 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3943 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3944 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3945 Apple Macintosh (MPW) host N/A
3947 stuff.c (Program to stuff files into a specially prepared space in kdb)
3948 kdb-start.c (Main loop for the standalone kernel debugger)
3950 Configurations that have been declared obsolete in this release have
3951 been commented out. Unless there is activity to revive these
3952 configurations, the next release of GDB will have their sources
3953 permanently REMOVED.
3955 * REMOVED configurations and files
3957 Altos 3068 m68*-altos-*
3958 Convex c1-*-*, c2-*-*
3960 ARM RISCix arm-*-* (as host)
3964 * GDB has been converted to ISO C.
3966 GDB's source code has been converted to ISO C. In particular, the
3967 sources are fully protoized, and rely on standard headers being
3972 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3974 * The MI enabled by default.
3976 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3977 revised and enabled by default. Packages which use GDB as a debugging
3978 engine behind a UI or another front end are encouraged to switch to
3979 using the GDB/MI interface, instead of the old annotations interface
3980 which is now deprecated.
3982 * Support for debugging Pascal programs.
3984 GDB now includes support for debugging Pascal programs. The following
3985 main features are supported:
3987 - Pascal-specific data types such as sets;
3989 - automatic recognition of Pascal sources based on file-name
3992 - Pascal-style display of data types, variables, and functions;
3994 - a Pascal expression parser.
3996 However, some important features are not yet supported.
3998 - Pascal string operations are not supported at all;
4000 - there are some problems with boolean types;
4002 - Pascal type hexadecimal constants are not supported
4003 because they conflict with the internal variables format;
4005 - support for Pascal objects and classes is not full yet;
4007 - unlike Pascal, GDB is case-sensitive for symbol names.
4009 * Changes in completion.
4011 Commands such as `shell', `run' and `set args', which pass arguments
4012 to inferior programs, now complete on file names, similar to what
4013 users expect at the shell prompt.
4015 Commands which accept locations, such as `disassemble', `print',
4016 `breakpoint', `until', etc. now complete on filenames as well as
4017 program symbols. Thus, if you type "break foob TAB", and the source
4018 files linked into the programs include `foobar.c', that file name will
4019 be one of the candidates for completion. However, file names are not
4020 considered for completion after you typed a colon that delimits a file
4021 name from a name of a function in that file, as in "break foo.c:bar".
4023 `set demangle-style' completes on available demangling styles.
4025 * New platform-independent commands:
4027 It is now possible to define a post-hook for a command as well as a
4028 hook that runs before the command. For more details, see the
4029 documentation of `hookpost' in the GDB manual.
4031 * Changes in GNU/Linux native debugging.
4033 Support for debugging multi-threaded programs has been completely
4034 revised for all platforms except m68k and sparc. You can now debug as
4035 many threads as your system allows you to have.
4037 Attach/detach is supported for multi-threaded programs.
4039 Support for SSE registers was added for x86. This doesn't work for
4040 multi-threaded programs though.
4042 * Changes in MIPS configurations.
4044 Multi-arch support is enabled for all MIPS configurations.
4046 GDB can now be built as native debugger on SGI Irix 6.x systems for
4047 debugging n32 executables. (Debugging 64-bit executables is not yet
4050 * Unified support for hardware watchpoints in all x86 configurations.
4052 Most (if not all) native x86 configurations support hardware-assisted
4053 breakpoints and watchpoints in a unified manner. This support
4054 implements debug register sharing between watchpoints, which allows to
4055 put a virtually infinite number of watchpoints on the same address,
4056 and also supports watching regions up to 16 bytes with several debug
4059 The new maintenance command `maintenance show-debug-regs' toggles
4060 debugging print-outs in functions that insert, remove, and test
4061 watchpoints and hardware breakpoints.
4063 * Changes in the DJGPP native configuration.
4065 New command ``info dos sysinfo'' displays assorted information about
4066 the CPU, OS, memory, and DPMI server.
4068 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4069 display information about segment descriptors stored in GDT, LDT, and
4072 New commands ``info dos pde'' and ``info dos pte'' display entries
4073 from Page Directory and Page Tables (for now works with CWSDPMI only).
4074 New command ``info dos address-pte'' displays the Page Table entry for
4075 a given linear address.
4077 GDB can now pass command lines longer than 126 characters to the
4078 program being debugged (requires an update to the libdbg.a library
4079 which is part of the DJGPP development kit).
4081 DWARF2 debug info is now supported.
4083 It is now possible to `step' and `next' through calls to `longjmp'.
4085 * Changes in documentation.
4087 All GDB documentation was converted to GFDL, the GNU Free
4088 Documentation License.
4090 Tracepoints-related commands are now fully documented in the GDB
4093 TUI, the Text-mode User Interface, is now documented in the manual.
4095 Tracepoints-related commands are now fully documented in the GDB
4098 The "GDB Internals" manual now has an index. It also includes
4099 documentation of `ui_out' functions, GDB coding standards, x86
4100 hardware watchpoints, and memory region attributes.
4102 * GDB's version number moved to ``version.in''
4104 The Makefile variable VERSION has been replaced by the file
4105 ``version.in''. People creating GDB distributions should update the
4106 contents of this file.
4110 GUD support is now a standard part of the EMACS distribution.
4112 *** Changes in GDB 5.0:
4114 * Improved support for debugging FP programs on x86 targets
4116 Unified and much-improved support for debugging floating-point
4117 programs on all x86 targets. In particular, ``info float'' now
4118 displays the FP registers in the same format on all x86 targets, with
4119 greater level of detail.
4121 * Improvements and bugfixes in hardware-assisted watchpoints
4123 It is now possible to watch array elements, struct members, and
4124 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4125 on x86 targets no longer erroneously trigger when the address is
4128 * Improvements in the native DJGPP version of GDB
4130 The distribution now includes all the scripts and auxiliary files
4131 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4132 machines ``out of the box''.
4134 The DJGPP version can now debug programs that use signals. It is
4135 possible to catch signals that happened in the debuggee, deliver
4136 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4137 would kill the program being debugged.) Programs that hook hardware
4138 interrupts (keyboard, timer, etc.) can also be debugged.
4140 It is now possible to debug DJGPP programs that redirect their
4141 standard handles or switch them to raw (as opposed to cooked) mode, or
4142 even close them. The command ``run < foo > bar'' works as expected,
4143 and ``info terminal'' reports useful information about the debuggee's
4144 terminal, including raw/cooked mode, redirection, etc.
4146 The DJGPP version now uses termios functions for console I/O, which
4147 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4150 DOS-style file names with drive letters are now fully supported by
4153 It is now possible to debug DJGPP programs that switch their working
4154 directory. It is also possible to rerun the debuggee any number of
4155 times without restarting GDB; thus, you can use the same setup,
4156 breakpoints, etc. for many debugging sessions.
4158 * New native configurations
4160 ARM GNU/Linux arm*-*-linux*
4161 PowerPC GNU/Linux powerpc-*-linux*
4165 Motorola MCore mcore-*-*
4166 x86 VxWorks i[3456]86-*-vxworks*
4167 PowerPC VxWorks powerpc-*-vxworks*
4168 TI TMS320C80 tic80-*-*
4170 * OBSOLETE configurations
4172 Altos 3068 m68*-altos-*
4173 Convex c1-*-*, c2-*-*
4175 ARM RISCix arm-*-* (as host)
4178 Configurations that have been declared obsolete will be commented out,
4179 but the code will be left in place. If there is no activity to revive
4180 these configurations before the next release of GDB, the sources will
4181 be permanently REMOVED.
4183 * Gould support removed
4185 Support for the Gould PowerNode and NP1 has been removed.
4187 * New features for SVR4
4189 On SVR4 native platforms (such as Solaris), if you attach to a process
4190 without first loading a symbol file, GDB will now attempt to locate and
4191 load symbols from the running process's executable file.
4193 * Many C++ enhancements
4195 C++ support has been greatly improved. Overload resolution now works properly
4196 in almost all cases. RTTI support is on the way.
4198 * Remote targets can connect to a sub-program
4200 A popen(3) style serial-device has been added. This device starts a
4201 sub-process (such as a stand-alone simulator) and then communicates
4202 with that. The sub-program to run is specified using the syntax
4203 ``|<program> <args>'' vis:
4205 (gdb) set remotedebug 1
4206 (gdb) target extended-remote |mn10300-elf-sim program-args
4208 * MIPS 64 remote protocol
4210 A long standing bug in the mips64 remote protocol where by GDB
4211 expected certain 32 bit registers (ex SR) to be transfered as 32
4212 instead of 64 bits has been fixed.
4214 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4215 added to provide backward compatibility with older versions of GDB.
4217 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4219 The command ``set remotebinarydownload'' command has been replaced by
4220 ``set remote X-packet''. Other commands in ``set remote'' family
4221 include ``set remote P-packet''.
4223 * Breakpoint commands accept ranges.
4225 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4226 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4227 ``tracepoint passcount'' also accepts a range of tracepoints.
4229 * ``apropos'' command added.
4231 The ``apropos'' command searches through command names and
4232 documentation strings, printing out matches, making it much easier to
4233 try to find a command that does what you are looking for.
4237 A new machine oriented interface (MI) has been added to GDB. This
4238 interface is designed for debug environments running GDB as a separate
4239 process. This is part of the long term libGDB project. See the
4240 "GDB/MI" chapter of the GDB manual for further information. It can be
4241 enabled by configuring with:
4243 .../configure --enable-gdbmi
4245 *** Changes in GDB-4.18:
4247 * New native configurations
4249 HP-UX 10.20 hppa*-*-hpux10.20
4250 HP-UX 11.x hppa*-*-hpux11.0*
4251 M68K GNU/Linux m68*-*-linux*
4255 Fujitsu FR30 fr30-*-elf*
4256 Intel StrongARM strongarm-*-*
4257 Mitsubishi D30V d30v-*-*
4259 * OBSOLETE configurations
4261 Gould PowerNode, NP1 np1-*-*, pn-*-*
4263 Configurations that have been declared obsolete will be commented out,
4264 but the code will be left in place. If there is no activity to revive
4265 these configurations before the next release of GDB, the sources will
4266 be permanently REMOVED.
4270 As a compatibility experiment, GDB's source files buildsym.h and
4271 buildsym.c have been converted to pure standard C, no longer
4272 containing any K&R compatibility code. We believe that all systems in
4273 use today either come with a standard C compiler, or have a GCC port
4274 available. If this is not true, please report the affected
4275 configuration to bug-gdb@gnu.org immediately. See the README file for
4276 information about getting a standard C compiler if you don't have one
4281 GDB now uses readline 2.2.
4283 * set extension-language
4285 You can now control the mapping between filename extensions and source
4286 languages by using the `set extension-language' command. For instance,
4287 you can ask GDB to treat .c files as C++ by saying
4288 set extension-language .c c++
4289 The command `info extensions' lists all of the recognized extensions
4290 and their associated languages.
4292 * Setting processor type for PowerPC and RS/6000
4294 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4295 you can use the `set processor' command to specify what variant of the
4296 PowerPC family you are debugging. The command
4300 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4301 following PowerPC and RS6000 variants:
4303 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4304 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4306 403GC IBM PowerPC 403GC
4307 505 Motorola PowerPC 505
4308 860 Motorola PowerPC 860 or 850
4309 601 Motorola PowerPC 601
4310 602 Motorola PowerPC 602
4311 603 Motorola/IBM PowerPC 603 or 603e
4312 604 Motorola PowerPC 604 or 604e
4313 750 Motorola/IBM PowerPC 750 or 750
4315 At the moment, this command just tells GDB what to name the
4316 special-purpose processor registers. Since almost all the affected
4317 registers are inaccessible to user-level programs, this command is
4318 only useful for remote debugging in its present form.
4322 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4323 more extensive support for HP-UX. Added features include shared
4324 library support, kernel threads and hardware watchpoints for 11.00,
4325 support for HP's ANSI C and C++ compilers, and a compatibility mode
4326 for xdb and dbx commands.
4330 HP's donation includes the new concept of catchpoints, which is a
4331 generalization of the old catch command. On HP-UX, it is now possible
4332 to catch exec, fork, and vfork, as well as library loading.
4334 This means that the existing catch command has changed; its first
4335 argument now specifies the type of catch to be set up. See the
4336 output of "help catch" for a list of catchpoint types.
4338 * Debugging across forks
4340 On HP-UX, you can choose which process to debug when a fork() happens
4345 HP has donated a curses-based terminal user interface (TUI). To get
4346 it, build with --enable-tui. Although this can be enabled for any
4347 configuration, at present it only works for native HP debugging.
4349 * GDB remote protocol additions
4351 A new protocol packet 'X' that writes binary data is now available.
4352 Default behavior is to try 'X', then drop back to 'M' if the stub
4353 fails to respond. The settable variable `remotebinarydownload'
4354 allows explicit control over the use of 'X'.
4356 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4357 full 64-bit address. The command
4359 set remoteaddresssize 32
4361 can be used to revert to the old behaviour. For existing remote stubs
4362 the change should not be noticed, as the additional address information
4365 In order to assist in debugging stubs, you may use the maintenance
4366 command `packet' to send any text string to the stub. For instance,
4368 maint packet heythere
4370 sends the packet "$heythere#<checksum>". Note that it is very easy to
4371 disrupt a debugging session by sending the wrong packet at the wrong
4374 The compare-sections command allows you to compare section data on the
4375 target to what is in the executable file without uploading or
4376 downloading, by comparing CRC checksums.
4378 * Tracing can collect general expressions
4380 You may now collect general expressions at tracepoints. This requires
4381 further additions to the target-side stub; see tracepoint.c and
4382 doc/agentexpr.texi for further details.
4384 * mask-address variable for Mips
4386 For Mips targets, you may control the zeroing of the upper 32 bits of
4387 a 64-bit address by entering `set mask-address on'. This is mainly
4388 of interest to users of embedded R4xxx and R5xxx processors.
4390 * Higher serial baud rates
4392 GDB's serial code now allows you to specify baud rates 57600, 115200,
4393 230400, and 460800 baud. (Note that your host system may not be able
4394 to achieve all of these rates.)
4398 The i960 configuration now includes an initial implementation of a
4399 builtin simulator, contributed by Jim Wilson.
4402 *** Changes in GDB-4.17:
4404 * New native configurations
4406 Alpha GNU/Linux alpha*-*-linux*
4407 Unixware 2.x i[3456]86-unixware2*
4408 Irix 6.x mips*-sgi-irix6*
4409 PowerPC GNU/Linux powerpc-*-linux*
4410 PowerPC Solaris powerpcle-*-solaris*
4411 Sparc GNU/Linux sparc-*-linux*
4412 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4416 Argonaut Risc Chip (ARC) arc-*-*
4417 Hitachi H8/300S h8300*-*-*
4418 Matsushita MN10200 w/simulator mn10200-*-*
4419 Matsushita MN10300 w/simulator mn10300-*-*
4420 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4421 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4422 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4423 Mitsubishi D10V w/simulator d10v-*-*
4424 Mitsubishi M32R/D w/simulator m32r-*-elf*
4425 Tsqware Sparclet sparclet-*-*
4426 NEC V850 w/simulator v850-*-*
4428 * New debugging protocols
4430 ARM with RDI protocol arm*-*-*
4431 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4432 DDB and LSI variants of PMON protocol mips*-*-*
4433 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4434 PowerPC with SDS protocol powerpc{,le}-*-eabi
4435 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4439 All configurations can now understand and use the DWARF 2 debugging
4440 format. The choice is automatic, if the symbol file contains DWARF 2
4445 GDB now includes basic Java language support. This support is
4446 only useful with Java compilers that produce native machine code.
4448 * solib-absolute-prefix and solib-search-path
4450 For SunOS and SVR4 shared libraries, you may now set the prefix for
4451 loading absolute shared library symbol files, and the search path for
4452 locating non-absolute shared library symbol files.
4454 * Live range splitting
4456 GDB can now effectively debug code for which GCC has performed live
4457 range splitting as part of its optimization. See gdb/doc/LRS for
4458 more details on the expected format of the stabs information.
4462 GDB's support for the GNU Hurd, including thread debugging, has been
4463 updated to work with current versions of the Hurd.
4467 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4468 instruction set. ARM GDB automatically detects when Thumb
4469 instructions are in use, and adjusts disassembly and backtracing
4474 GDB's MIPS target configurations now handle the MIP16 16-bit
4479 GDB now includes support for overlays; if an executable has been
4480 linked such that multiple sections are based at the same address, GDB
4481 will decide which section to use for symbolic info. You can choose to
4482 control the decision manually, using overlay commands, or implement
4483 additional target-side support and use "overlay load-target" to bring
4484 in the overlay mapping. Do "help overlay" for more detail.
4488 The command "info symbol <address>" displays information about
4489 the symbol at the specified address.
4493 The standard remote protocol now includes an extension that allows
4494 asynchronous collection and display of trace data. This requires
4495 extensive support in the target-side debugging stub. Tracing mode
4496 includes a new interaction mode in GDB and new commands: see the
4497 file tracepoint.c for more details.
4501 Configurations for embedded MIPS now include a simulator contributed
4502 by Cygnus Solutions. The simulator supports the instruction sets
4503 of most MIPS variants.
4507 Sparc configurations may now include the ERC32 simulator contributed
4508 by the European Space Agency. The simulator is not built into
4509 Sparc targets by default; configure with --enable-sim to include it.
4513 For target configurations that may include multiple variants of a
4514 basic architecture (such as MIPS and SH), you may now set the
4515 architecture explicitly. "set arch" sets, "info arch" lists
4516 the possible architectures.
4518 *** Changes in GDB-4.16:
4520 * New native configurations
4522 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4523 M68K NetBSD m68k-*-netbsd*
4524 PowerPC AIX 4.x powerpc-*-aix*
4525 PowerPC MacOS powerpc-*-macos*
4526 PowerPC Windows NT powerpcle-*-cygwin32
4527 RS/6000 AIX 4.x rs6000-*-aix4*
4531 ARM with RDP protocol arm-*-*
4532 I960 with MON960 i960-*-coff
4533 MIPS VxWorks mips*-*-vxworks*
4534 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4535 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4537 Matra Sparclet sparclet-*-*
4541 The powerpc-eabi configuration now includes the PSIM simulator,
4542 contributed by Andrew Cagney, with assistance from Mike Meissner.
4543 PSIM is a very elaborate model of the PowerPC, including not only
4544 basic instruction set execution, but also details of execution unit
4545 performance and I/O hardware. See sim/ppc/README for more details.
4549 GDB now works with Solaris 2.5.
4551 * Windows 95/NT native
4553 GDB will now work as a native debugger on Windows 95 and Windows NT.
4554 To build it from source, you must use the "gnu-win32" environment,
4555 which uses a DLL to emulate enough of Unix to run the GNU tools.
4556 Further information, binaries, and sources are available at
4557 ftp.cygnus.com, under pub/gnu-win32.
4559 * dont-repeat command
4561 If a user-defined command includes the command `dont-repeat', then the
4562 command will not be repeated if the user just types return. This is
4563 useful if the command is time-consuming to run, so that accidental
4564 extra keystrokes don't run the same command many times.
4566 * Send break instead of ^C
4568 The standard remote protocol now includes an option to send a break
4569 rather than a ^C to the target in order to interrupt it. By default,
4570 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4572 * Remote protocol timeout
4574 The standard remote protocol includes a new variable `remotetimeout'
4575 that allows you to set the number of seconds before GDB gives up trying
4576 to read from the target. The default value is 2.
4578 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4580 By default GDB will automatically keep track of objects as they are
4581 loaded and unloaded by the dynamic linker. By using the command `set
4582 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4583 when shared library events occur, thus allowing you to set breakpoints
4584 in shared libraries which are explicitly loaded by the inferior.
4586 Note this feature does not work on hpux8. On hpux9 you must link
4587 /usr/lib/end.o into your program. This feature should work
4588 automatically on hpux10.
4590 * Irix 5.x hardware watchpoint support
4592 Irix 5 configurations now support the use of hardware watchpoints.
4594 * Mips protocol "SYN garbage limit"
4596 When debugging a Mips target using the `target mips' protocol, you
4597 may set the number of characters that GDB will ignore by setting
4598 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4599 every character. The default value is 1050.
4601 * Recording and replaying remote debug sessions
4603 If you set `remotelogfile' to the name of a file, gdb will write to it
4604 a recording of a remote debug session. This recording may then be
4605 replayed back to gdb using "gdbreplay". See gdbserver/README for
4606 details. This is useful when you have a problem with GDB while doing
4607 remote debugging; you can make a recording of the session and send it
4608 to someone else, who can then recreate the problem.
4610 * Speedups for remote debugging
4612 GDB includes speedups for downloading and stepping MIPS systems using
4613 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4614 and more efficient S-record downloading.
4616 * Memory use reductions and statistics collection
4618 GDB now uses less memory and reports statistics about memory usage.
4619 Try the `maint print statistics' command, for example.
4621 *** Changes in GDB-4.15:
4623 * Psymtabs for XCOFF
4625 The symbol reader for AIX GDB now uses partial symbol tables. This
4626 can greatly improve startup time, especially for large executables.
4628 * Remote targets use caching
4630 Remote targets now use a data cache to speed up communication with the
4631 remote side. The data cache could lead to incorrect results because
4632 it doesn't know about volatile variables, thus making it impossible to
4633 debug targets which use memory mapped I/O devices. `set remotecache
4634 off' turns the the data cache off.
4636 * Remote targets may have threads
4638 The standard remote protocol now includes support for multiple threads
4639 in the target system, using new protocol commands 'H' and 'T'. See
4640 gdb/remote.c for details.
4644 If GDB is configured with `--enable-netrom', then it will include
4645 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4646 acts as though it is a bank of ROM on the target board, but you can
4647 write into it over the network. GDB's support consists only of
4648 support for fast loading into the emulated ROM; to debug, you must use
4649 another protocol, such as standard remote protocol. The usual
4650 sequence is something like
4652 target nrom <netrom-hostname>
4654 target remote <netrom-hostname>:1235
4658 GDB now includes support for the Apple Macintosh, as a host only. It
4659 may be run as either an MPW tool or as a standalone application, and
4660 it can debug through the serial port. All the usual GDB commands are
4661 available, but to the target command, you must supply "serial" as the
4662 device type instead of "/dev/ttyXX". See mpw-README in the main
4663 directory for more information on how to build. The MPW configuration
4664 scripts */mpw-config.in support only a few targets, and only the
4665 mips-idt-ecoff target has been tested.
4669 GDB configuration now uses autoconf. This is not user-visible,
4670 but does simplify configuration and building.
4674 GDB now supports hpux10.
4676 *** Changes in GDB-4.14:
4678 * New native configurations
4680 x86 FreeBSD i[345]86-*-freebsd
4681 x86 NetBSD i[345]86-*-netbsd
4682 NS32k NetBSD ns32k-*-netbsd
4683 Sparc NetBSD sparc-*-netbsd
4687 A29K VxWorks a29k-*-vxworks
4688 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4689 CPU32 EST-300 emulator m68*-*-est*
4690 PowerPC ELF powerpc-*-elf
4693 * Alpha OSF/1 support for procfs
4695 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4696 possible to attach to running processes. As the mounting of the /proc
4697 filesystem is optional on the Alpha, GDB automatically determines
4698 the availability of /proc during startup. This can lead to problems
4699 if /proc is unmounted after GDB has been started.
4701 * Arguments to user-defined commands
4703 User commands may accept up to 10 arguments separated by whitespace.
4704 Arguments are accessed within the user command via $arg0..$arg9. A
4707 print $arg0 + $arg1 + $arg2
4709 To execute the command use:
4712 Defines the command "adder" which prints the sum of its three arguments.
4713 Note the arguments are text substitutions, so they may reference variables,
4714 use complex expressions, or even perform inferior function calls.
4716 * New `if' and `while' commands
4718 This makes it possible to write more sophisticated user-defined
4719 commands. Both commands take a single argument, which is the
4720 expression to evaluate, and must be followed by the commands to
4721 execute, one per line, if the expression is nonzero, the list being
4722 terminated by the word `end'. The `if' command list may include an
4723 `else' word, which causes the following commands to be executed only
4724 if the expression is zero.
4726 * Fortran source language mode
4728 GDB now includes partial support for Fortran 77. It will recognize
4729 Fortran programs and can evaluate a subset of Fortran expressions, but
4730 variables and functions may not be handled correctly. GDB will work
4731 with G77, but does not yet know much about symbols emitted by other
4734 * Better HPUX support
4736 Most debugging facilities now work on dynamic executables for HPPAs
4737 running hpux9 or later. You can attach to running dynamically linked
4738 processes, but by default the dynamic libraries will be read-only, so
4739 for instance you won't be able to put breakpoints in them. To change
4740 that behavior do the following before running the program:
4746 This will cause the libraries to be mapped private and read-write.
4747 To revert to the normal behavior, do this:
4753 You cannot set breakpoints or examine data in the library until after
4754 the library is loaded if the function/data symbols do not have
4757 GDB can now also read debug symbols produced by the HP C compiler on
4758 HPPAs (sorry, no C++, Fortran or 68k support).
4760 * Target byte order now dynamically selectable
4762 You can choose which byte order to use with a target system, via the
4763 commands "set endian big" and "set endian little", and you can see the
4764 current setting by using "show endian". You can also give the command
4765 "set endian auto", in which case GDB will use the byte order
4766 associated with the executable. Currently, only embedded MIPS
4767 configurations support dynamic selection of target byte order.
4769 * New DOS host serial code
4771 This version uses DPMI interrupts to handle buffered I/O, so you
4772 no longer need to run asynctsr when debugging boards connected to
4775 *** Changes in GDB-4.13:
4777 * New "complete" command
4779 This lists all the possible completions for the rest of the line, if it
4780 were to be given as a command itself. This is intended for use by emacs.
4782 * Trailing space optional in prompt
4784 "set prompt" no longer adds a space for you after the prompt you set. This
4785 allows you to set a prompt which ends in a space or one that does not.
4787 * Breakpoint hit counts
4789 "info break" now displays a count of the number of times the breakpoint
4790 has been hit. This is especially useful in conjunction with "ignore"; you
4791 can ignore a large number of breakpoint hits, look at the breakpoint info
4792 to see how many times the breakpoint was hit, then run again, ignoring one
4793 less than that number, and this will get you quickly to the last hit of
4796 * Ability to stop printing at NULL character
4798 "set print null-stop" will cause GDB to stop printing the characters of
4799 an array when the first NULL is encountered. This is useful when large
4800 arrays actually contain only short strings.
4802 * Shared library breakpoints
4804 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4805 breakpoints in shared libraries before the executable is run.
4807 * Hardware watchpoints
4809 There is a new hardware breakpoint for the watch command for sparclite
4810 targets. See gdb/sparclite/hw_breakpoint.note.
4812 Hardware watchpoints are also now supported under GNU/Linux.
4816 Annotations have been added. These are for use with graphical interfaces,
4817 and are still experimental. Currently only gdba.el uses these.
4819 * Improved Irix 5 support
4821 GDB now works properly with Irix 5.2.
4823 * Improved HPPA support
4825 GDB now works properly with the latest GCC and GAS.
4827 * New native configurations
4829 Sequent PTX4 i[34]86-sequent-ptx4
4830 HPPA running OSF/1 hppa*-*-osf*
4831 Atari TT running SVR4 m68*-*-sysv4*
4832 RS/6000 LynxOS rs6000-*-lynxos*
4836 OS/9000 i[34]86-*-os9k
4837 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4840 * Hitachi SH7000 and E7000-PC ICE support
4842 There is now support for communicating with the Hitachi E7000-PC ICE.
4843 This is available automatically when GDB is configured for the SH.
4847 As usual, a variety of small fixes and improvements, both generic
4848 and configuration-specific. See the ChangeLog for more detail.
4850 *** Changes in GDB-4.12:
4852 * Irix 5 is now supported
4856 GDB-4.12 on the HPPA has a number of changes which make it unable
4857 to debug the output from the currently released versions of GCC and
4858 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4859 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4860 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4863 *** Changes in GDB-4.11:
4865 * User visible changes:
4869 The "set remotedebug" option is now consistent between the mips remote
4870 target, remote targets using the gdb-specific protocol, UDI (AMD's
4871 debug protocol for the 29k) and the 88k bug monitor. It is now an
4872 integer specifying a debug level (normally 0 or 1, but 2 means more
4873 debugging info for the mips target).
4875 * DEC Alpha native support
4877 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4878 debug info, but GDB works fairly well with the DEC compiler and should
4879 work with a future GCC release. See the README file for a few
4880 Alpha-specific notes.
4882 * Preliminary thread implementation
4884 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4886 * LynxOS native and target support for 386
4888 This release has been hosted on LynxOS 2.2, and also can be configured
4889 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4892 * Improvements in C++ mangling/demangling.
4894 This release has much better g++ debugging, specifically in name
4895 mangling/demangling, virtual function calls, print virtual table,
4896 call methods, ...etc.
4898 *** Changes in GDB-4.10:
4900 * User visible changes:
4902 Remote debugging using the GDB-specific (`target remote') protocol now
4903 supports the `load' command. This is only useful if you have some
4904 other way of getting the stub to the target system, and you can put it
4905 somewhere in memory where it won't get clobbered by the download.
4907 Filename completion now works.
4909 When run under emacs mode, the "info line" command now causes the
4910 arrow to point to the line specified. Also, "info line" prints
4911 addresses in symbolic form (as well as hex).
4913 All vxworks based targets now support a user settable option, called
4914 vxworks-timeout. This option represents the number of seconds gdb
4915 should wait for responses to rpc's. You might want to use this if
4916 your vxworks target is, perhaps, a slow software simulator or happens
4917 to be on the far side of a thin network line.
4921 This release contains support for using a DEC alpha as a GDB host for
4922 cross debugging. Native alpha debugging is not supported yet.
4925 *** Changes in GDB-4.9:
4929 This is the first GDB release which is accompanied by a matching testsuite.
4930 The testsuite requires installation of dejagnu, which should be available
4931 via ftp from most sites that carry GNU software.
4935 'Cfront' style demangling has had its name changed to 'ARM' style, to
4936 emphasize that it was written from the specifications in the C++ Annotated
4937 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4938 disclaimers, it still generated too much confusion with users attempting to
4939 use gdb with AT&T cfront.
4943 GDB now uses a standard remote interface to a simulator library.
4944 So far, the library contains simulators for the Zilog Z8001/2, the
4945 Hitachi H8/300, H8/500 and Super-H.
4947 * New targets supported
4949 H8/300 simulator h8300-hitachi-hms or h8300hms
4950 H8/500 simulator h8500-hitachi-hms or h8500hms
4951 SH simulator sh-hitachi-hms or sh
4952 Z8000 simulator z8k-zilog-none or z8ksim
4953 IDT MIPS board over serial line mips-idt-ecoff
4955 Cross-debugging to GO32 targets is supported. It requires a custom
4956 version of the i386-stub.c module which is integrated with the
4957 GO32 memory extender.
4959 * New remote protocols
4961 MIPS remote debugging protocol.
4963 * New source languages supported
4965 This version includes preliminary support for Chill, a Pascal like language
4966 used by telecommunications companies. Chill support is also being integrated
4967 into the GNU compiler, but we don't know when it will be publically available.
4970 *** Changes in GDB-4.8:
4972 * HP Precision Architecture supported
4974 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4975 version of this support was available as a set of patches from the
4976 University of Utah. GDB does not support debugging of programs
4977 compiled with the HP compiler, because HP will not document their file
4978 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4979 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4981 Many problems in the preliminary version have been fixed.
4983 * Faster and better demangling
4985 We have improved template demangling and fixed numerous bugs in the GNU style
4986 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4987 character types (wchar_t) are now supported. Demangling of each symbol is now
4988 only done once, and is cached when the symbol table for a file is read in.
4989 This results in a small increase in memory usage for C programs, a moderate
4990 increase in memory usage for C++ programs, and a fantastic speedup in
4993 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4994 from the specifications in the Annotated Reference Manual, which AT&T's
4995 compiler does not actually implement.
4997 * G++ multiple inheritance compiler problem
4999 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5000 inheritance lattices was reworked to properly discover ambiguities. We
5001 recently found an example which causes this new algorithm to fail in a
5002 very subtle way, producing bad debug information for those classes.
5003 The file 'gcc.patch' (in this directory) can be applied to gcc to
5004 circumvent the problem. A future GCC release will contain a complete
5007 The previous G++ debug info problem (mentioned below for the gdb-4.7
5008 release) is fixed in gcc version 2.3.2.
5010 * Improved configure script
5012 The `configure' script will now attempt to guess your system type if
5013 you don't supply a host system type. The old scheme of supplying a
5014 host system triplet is preferable over using this. All the magic is
5015 done in the new `config.guess' script. Examine it for details.
5017 We have also brought our configure script much more in line with the FSF's
5018 version. It now supports the --with-xxx options. In particular,
5019 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5020 The resulting GDB will not be able to read arbitrary object file formats --
5021 only the format ``expected'' to be used on the configured target system.
5022 We hope to make this the default in a future release.
5024 * Documentation improvements
5026 There's new internal documentation on how to modify GDB, and how to
5027 produce clean changes to the code. We implore people to read it
5028 before submitting changes.
5030 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5031 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5032 `info' files are also provided. To build `info' files from scratch,
5033 you will need the latest `makeinfo' release, which will be available in
5034 a future texinfo-X.Y release.
5036 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5037 We're not sure exactly which versions have this problem, but it has
5038 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5039 or better. If that isn't possible, there is a patch in
5040 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5041 around this problem.
5045 GDB now supports array constants that can be used in expressions typed in by
5046 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5047 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5050 The new directory `gdb/sparclite' contains a program that demonstrates
5051 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5053 * New native hosts supported
5055 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5056 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5058 * New targets supported
5060 AMD 29k family via UDI a29k-amd-udi or udi29k
5062 * New file formats supported
5064 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5065 HPUX core files, and SCO 3.2v2 core files.
5069 Attaching to processes now works again; thanks for the many bug reports.
5071 We have also stomped on a bunch of core dumps caused by
5072 printf_filtered("%s") problems.
5074 We eliminated a copyright problem on the rpc and ptrace header files
5075 for VxWorks, which was discovered at the last minute during the 4.7
5076 release. You should now be able to build a VxWorks GDB.
5078 You can now interrupt gdb while an attached process is running. This
5079 will cause the attached process to stop, and give control back to GDB.
5081 We fixed problems caused by using too many file descriptors
5082 for reading symbols from object files and libraries. This was
5083 especially a problem for programs that used many (~100) shared
5086 The `step' command now only enters a subroutine if there is line number
5087 information for the subroutine. Otherwise it acts like the `next'
5088 command. Previously, `step' would enter subroutines if there was
5089 any debugging information about the routine. This avoids problems
5090 when using `cc -g1' on MIPS machines.
5092 * Internal improvements
5094 GDB's internal interfaces have been improved to make it easier to support
5095 debugging of multiple languages in the future.
5097 GDB now uses a common structure for symbol information internally.
5098 Minimal symbols (derived from linkage symbols in object files), partial
5099 symbols (from a quick scan of debug information), and full symbols
5100 contain a common subset of information, making it easier to write
5101 shared code that handles any of them.
5103 * New command line options
5105 We now accept --silent as an alias for --quiet.
5109 The memory-mapped-malloc library is now licensed under the GNU Library
5110 General Public License.
5112 *** Changes in GDB-4.7:
5114 * Host/native/target split
5116 GDB has had some major internal surgery to untangle the support for
5117 hosts and remote targets. Now, when you configure GDB for a remote
5118 target, it will no longer load in all of the support for debugging
5119 local programs on the host. When fully completed and tested, this will
5120 ensure that arbitrary host/target combinations are possible.
5122 The primary conceptual shift is to separate the non-portable code in
5123 GDB into three categories. Host specific code is required any time GDB
5124 is compiled on that host, regardless of the target. Target specific
5125 code relates to the peculiarities of the target, but can be compiled on
5126 any host. Native specific code is everything else: it can only be
5127 built when the host and target are the same system. Child process
5128 handling and core file support are two common `native' examples.
5130 GDB's use of /proc for controlling Unix child processes is now cleaner.
5131 It has been split out into a single module under the `target_ops' vector,
5132 plus two native-dependent functions for each system that uses /proc.
5134 * New hosts supported
5136 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5137 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5138 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5140 * New targets supported
5142 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5143 68030 and CPU32 m68030-*-*, m68332-*-*
5145 * New native hosts supported
5147 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5148 (386bsd is not well tested yet)
5149 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5151 * New file formats supported
5153 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5154 supports reading of `a.out.adobe' object files, which are an a.out
5155 format extended with minimal information about multiple sections.
5159 `show copying' is the same as the old `info copying'.
5160 `show warranty' is the same as `info warrantee'.
5161 These were renamed for consistency. The old commands continue to work.
5163 `info handle' is a new alias for `info signals'.
5165 You can now define pre-command hooks, which attach arbitrary command
5166 scripts to any command. The commands in the hook will be executed
5167 prior to the user's command. You can also create a hook which will be
5168 executed whenever the program stops. See gdb.texinfo.
5172 We now deal with Cfront style name mangling, and can even extract type
5173 info from mangled symbols. GDB can automatically figure out which
5174 symbol mangling style your C++ compiler uses.
5176 Calling of methods and virtual functions has been improved as well.
5180 The crash that occured when debugging Sun Ansi-C compiled binaries is
5181 fixed. This was due to mishandling of the extra N_SO stabs output
5184 We also finally got Ultrix 4.2 running in house, and fixed core file
5185 support, with help from a dozen people on the net.
5187 John M. Farrell discovered that the reason that single-stepping was so
5188 slow on all of the Mips based platforms (primarily SGI and DEC) was
5189 that we were trying to demangle and lookup a symbol used for internal
5190 purposes on every instruction that was being stepped through. Changing
5191 the name of that symbol so that it couldn't be mistaken for a C++
5192 mangled symbol sped things up a great deal.
5194 Rich Pixley sped up symbol lookups in general by getting much smarter
5195 about when C++ symbol mangling is necessary. This should make symbol
5196 completion (TAB on the command line) much faster. It's not as fast as
5197 we'd like, but it's significantly faster than gdb-4.6.
5201 A new user controllable variable 'call_scratch_address' can
5202 specify the location of a scratch area to be used when GDB
5203 calls a function in the target. This is necessary because the
5204 usual method of putting the scratch area on the stack does not work
5205 in systems that have separate instruction and data spaces.
5207 We integrated changes to support the 29k UDI (Universal Debugger
5208 Interface), but discovered at the last minute that we didn't have all
5209 of the appropriate copyright paperwork. We are working with AMD to
5210 resolve this, and hope to have it available soon.
5214 We have sped up the remote serial line protocol, especially for targets
5215 with lots of registers. It now supports a new `expedited status' ('T')
5216 message which can be used in place of the existing 'S' status message.
5217 This allows the remote stub to send only the registers that GDB
5218 needs to make a quick decision about single-stepping or conditional
5219 breakpoints, eliminating the need to fetch the entire register set for
5220 each instruction being stepped through.
5222 The GDB remote serial protocol now implements a write-through cache for
5223 registers, only re-reading the registers if the target has run.
5225 There is also a new remote serial stub for SPARC processors. You can
5226 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5227 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5228 processor with a serial port.
5232 Configure.in files have become much easier to read and modify. A new
5233 `table driven' format makes it more obvious what configurations are
5234 supported, and what files each one uses.
5238 There is a new opcodes library which will eventually contain all of the
5239 disassembly routines and opcode tables. At present, it only contains
5240 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5241 disassembler (binutils/objdump) to share these routines.
5243 The libiberty library is now copylefted under the GNU Library General
5244 Public License. This allows more liberal use, and was done so libg++
5245 can use it. This makes no difference to GDB, since the Library License
5246 grants all the rights from the General Public License.
5250 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5251 reference to the stabs symbol info used by the debugger. It is (as far
5252 as we know) the only published document on this fascinating topic. We
5253 encourage you to read it, compare it to the stabs information on your
5254 system, and send improvements on the document in general (to
5255 bug-gdb@prep.ai.mit.edu).
5257 And, of course, many bugs have been fixed.
5260 *** Changes in GDB-4.6:
5262 * Better support for C++ function names
5264 GDB now accepts as input the "demangled form" of C++ overloaded function
5265 names and member function names, and can do command completion on such names
5266 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5267 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5268 Make use of command completion, it is your friend.
5270 GDB also now accepts a variety of C++ mangled symbol formats. They are
5271 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5272 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5273 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5274 for the list of formats.
5276 * G++ symbol mangling problem
5278 Recent versions of gcc have a bug in how they emit debugging information for
5279 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5280 directory) can be applied to gcc to fix the problem. Alternatively, if you
5281 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5282 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5283 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5286 * New 'maintenance' command
5288 All of the commands related to hacking GDB internals have been moved out of
5289 the main command set, and now live behind the 'maintenance' command. This
5290 can also be abbreviated as 'mt'. The following changes were made:
5292 dump-me -> maintenance dump-me
5293 info all-breakpoints -> maintenance info breakpoints
5294 printmsyms -> maintenance print msyms
5295 printobjfiles -> maintenance print objfiles
5296 printpsyms -> maintenance print psymbols
5297 printsyms -> maintenance print symbols
5299 The following commands are new:
5301 maintenance demangle Call internal GDB demangler routine to
5302 demangle a C++ link name and prints the result.
5303 maintenance print type Print a type chain for a given symbol
5305 * Change to .gdbinit file processing
5307 We now read the $HOME/.gdbinit file before processing the argv arguments
5308 (e.g. reading symbol files or core files). This allows global parameters to
5309 be set, which will apply during the symbol reading. The ./.gdbinit is still
5310 read after argv processing.
5312 * New hosts supported
5314 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5316 GNU/Linux support i386-unknown-linux or linux
5318 We are also including code to support the HP/PA running BSD and HPUX. This
5319 is almost guaranteed not to work, as we didn't have time to test or build it
5320 for this release. We are including it so that the more adventurous (or
5321 masochistic) of you can play with it. We also had major problems with the
5322 fact that the compiler that we got from HP doesn't support the -g option.
5325 * New targets supported
5327 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5329 * More smarts about finding #include files
5331 GDB now remembers the compilation directory for all include files, and for
5332 all files from which C is generated (like yacc and lex sources). This
5333 greatly improves GDB's ability to find yacc/lex sources, and include files,
5334 especially if you are debugging your program from a directory different from
5335 the one that contains your sources.
5337 We also fixed a bug which caused difficulty with listing and setting
5338 breakpoints in include files which contain C code. (In the past, you had to
5339 try twice in order to list an include file that you hadn't looked at before.)
5341 * Interesting infernals change
5343 GDB now deals with arbitrary numbers of sections, where the symbols for each
5344 section must be relocated relative to that section's landing place in the
5345 target's address space. This work was needed to support ELF with embedded
5346 stabs used by Solaris-2.0.
5348 * Bug fixes (of course!)
5350 There have been loads of fixes for the following things:
5351 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5352 i960, stabs, DOS(GO32), procfs, etc...
5354 See the ChangeLog for details.
5356 *** Changes in GDB-4.5:
5358 * New machines supported (host and target)
5360 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5362 SGI Irix-4.x mips-sgi-irix4 or iris4
5364 * New malloc package
5366 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5367 Mmalloc is capable of handling mutiple heaps of memory. It is also
5368 capable of saving a heap to a file, and then mapping it back in later.
5369 This can be used to greatly speedup the startup of GDB by using a
5370 pre-parsed symbol table which lives in a mmalloc managed heap. For
5371 more details, please read mmalloc/mmalloc.texi.
5375 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5376 'help info proc' for details.
5378 * MIPS ecoff symbol table format
5380 The code that reads MIPS symbol table format is now supported on all hosts.
5381 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5384 * File name changes for MS-DOS
5386 Many files in the config directories have been renamed to make it easier to
5387 support GDB on MS-DOSe systems (which have very restrictive file name
5388 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5389 environment) is close to working but has some remaining problems. Note
5390 that debugging of DOS programs is not supported, due to limitations
5391 in the ``operating system'', but it can be used to host cross-debugging.
5393 * Cross byte order fixes
5395 Many fixes have been made to support cross debugging of Sparc and MIPS
5396 targets from hosts whose byte order differs.
5398 * New -mapped and -readnow options
5400 If memory-mapped files are available on your system through the 'mmap'
5401 system call, you can use the -mapped option on the `file' or
5402 `symbol-file' commands to cause GDB to write the symbols from your
5403 program into a reusable file. If the program you are debugging is
5404 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5405 Future GDB debugging sessions will notice the presence of this file,
5406 and will quickly map in symbol information from it, rather than reading
5407 the symbol table from the executable program. Using the '-mapped'
5408 option in a GDB `file' or `symbol-file' command has the same effect as
5409 starting GDB with the '-mapped' command-line option.
5411 You can cause GDB to read the entire symbol table immediately by using
5412 the '-readnow' option with any of the commands that load symbol table
5413 information (or on the GDB command line). This makes the command
5414 slower, but makes future operations faster.
5416 The -mapped and -readnow options are typically combined in order to
5417 build a `fred.syms' file that contains complete symbol information.
5418 A simple GDB invocation to do nothing but build a `.syms' file for future
5421 gdb -batch -nx -mapped -readnow programname
5423 The `.syms' file is specific to the host machine on which GDB is run.
5424 It holds an exact image of GDB's internal symbol table. It cannot be
5425 shared across multiple host platforms.
5427 * longjmp() handling
5429 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5430 siglongjmp() without losing control. This feature has not yet been ported to
5431 all systems. It currently works on many 386 platforms, all MIPS-based
5432 platforms (SGI, DECstation, etc), and Sun3/4.
5436 Preliminary work has been put in to support the new Solaris OS from Sun. At
5437 this time, it can control and debug processes, but it is not capable of
5442 As always, many many bug fixes. The major areas were with g++, and mipsread.
5443 People using the MIPS-based platforms should experience fewer mysterious
5444 crashes and trashed symbol tables.
5446 *** Changes in GDB-4.4:
5448 * New machines supported (host and target)
5450 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5452 BSD Reno on Vax vax-dec-bsd
5453 Ultrix on Vax vax-dec-ultrix
5455 * New machines supported (target)
5457 AMD 29000 embedded, using EBMON a29k-none-none
5461 GDB continues to improve its handling of C++. `References' work better.
5462 The demangler has also been improved, and now deals with symbols mangled as
5463 per the Annotated C++ Reference Guide.
5465 GDB also now handles `stabs' symbol information embedded in MIPS
5466 `ecoff' symbol tables. Since the ecoff format was not easily
5467 extensible to handle new languages such as C++, this appeared to be a
5468 good way to put C++ debugging info into MIPS binaries. This option
5469 will be supported in the GNU C compiler, version 2, when it is
5472 * New features for SVR4
5474 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5475 shared libraries. Debugging dynamically linked programs should present
5476 only minor differences from debugging statically linked programs.
5478 The `info proc' command will print out information about any process
5479 on an SVR4 system (including the one you are debugging). At the moment,
5480 it prints the address mappings of the process.
5482 If you bring up GDB on another SVR4 system, please send mail to
5483 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5485 * Better dynamic linking support in SunOS
5487 Reading symbols from shared libraries which contain debugging symbols
5488 now works properly. However, there remain issues such as automatic
5489 skipping of `transfer vector' code during function calls, which
5490 make it harder to debug code in a shared library, than to debug the
5491 same code linked statically.
5495 GDB is now using the latest `getopt' routines from the FSF. This
5496 version accepts the -- prefix for options with long names. GDB will
5497 continue to accept the old forms (-option and +option) as well.
5498 Various single letter abbreviations for options have been explicity
5499 added to the option table so that they won't get overshadowed in the
5500 future by other options that begin with the same letter.
5504 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5505 Many assorted bugs have been handled. Many more remain to be handled.
5506 See the various ChangeLog files (primarily in gdb and bfd) for details.
5509 *** Changes in GDB-4.3:
5511 * New machines supported (host and target)
5513 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5514 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5515 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5517 * Almost SCO Unix support
5519 We had hoped to support:
5520 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5521 (except for core file support), but we discovered very late in the release
5522 that it has problems with process groups that render gdb unusable. Sorry
5523 about that. I encourage people to fix it and post the fixes.
5525 * Preliminary ELF and DWARF support
5527 GDB can read ELF object files on System V Release 4, and can handle
5528 debugging records for C, in DWARF format, in ELF files. This support
5529 is preliminary. If you bring up GDB on another SVR4 system, please
5530 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5535 GDB now uses the latest `readline' library. One user-visible change
5536 is that two tabs will list possible command completions, which previously
5537 required typing M-? (meta-question mark, or ESC ?).
5541 The `stepi' bug that many of you noticed has been squashed.
5542 Many bugs in C++ have been handled. Many more remain to be handled.
5543 See the various ChangeLog files (primarily in gdb and bfd) for details.
5545 * State of the MIPS world (in case you wondered):
5547 GDB can understand the symbol tables emitted by the compilers
5548 supplied by most vendors of MIPS-based machines, including DEC. These
5549 symbol tables are in a format that essentially nobody else uses.
5551 Some versions of gcc come with an assembler post-processor called
5552 mips-tfile. This program is required if you want to do source-level
5553 debugging of gcc-compiled programs. I believe FSF does not ship
5554 mips-tfile with gcc version 1, but it will eventually come with gcc
5557 Debugging of g++ output remains a problem. g++ version 1.xx does not
5558 really support it at all. (If you're lucky, you should be able to get
5559 line numbers and stack traces to work, but no parameters or local
5560 variables.) With some work it should be possible to improve the
5563 When gcc version 2 is released, you will have somewhat better luck.
5564 However, even then you will get confusing results for inheritance and
5567 We will eventually provide full debugging of g++ output on
5568 DECstations. This will probably involve some kind of stabs-in-ecoff
5569 encapulation, but the details have not been worked out yet.
5572 *** Changes in GDB-4.2:
5574 * Improved configuration
5576 Only one copy of `configure' exists now, and it is not self-modifying.
5577 Porting BFD is simpler.
5581 The `step' and `next' commands now only stop at the first instruction
5582 of a source line. This prevents the multiple stops that used to occur
5583 in switch statements, for-loops, etc. `Step' continues to stop if a
5584 function that has debugging information is called within the line.
5588 Lots of small bugs fixed. More remain.
5590 * New host supported (not target)
5592 Intel 386 PC clone running Mach i386-none-mach
5595 *** Changes in GDB-4.1:
5597 * Multiple source language support
5599 GDB now has internal scaffolding to handle several source languages.
5600 It determines the type of each source file from its filename extension,
5601 and will switch expression parsing and number formatting to match the
5602 language of the function in the currently selected stack frame.
5603 You can also specifically set the language to be used, with
5604 `set language c' or `set language modula-2'.
5608 GDB now has preliminary support for the GNU Modula-2 compiler,
5609 currently under development at the State University of New York at
5610 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5611 continue through the fall of 1991 and into 1992.
5613 Other Modula-2 compilers are currently not supported, and attempting to
5614 debug programs compiled with them will likely result in an error as the
5615 symbol table is read. Feel free to work on it, though!
5617 There are hooks in GDB for strict type checking and range checking,
5618 in the `Modula-2 philosophy', but they do not currently work.
5622 GDB can now write to executable and core files (e.g. patch
5623 a variable's value). You must turn this switch on, specify
5624 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5625 by assigning a new value to a variable. Modifications take
5628 * Automatic SunOS shared library reading
5630 When you run your program, GDB automatically determines where its
5631 shared libraries (if any) have been loaded, and reads their symbols.
5632 The `share' command is no longer needed. This also works when
5633 examining core files.
5637 You can specify the number of lines that the `list' command shows.
5640 * New machines supported (host and target)
5642 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5643 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5644 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5646 * New hosts supported (not targets)
5648 IBM RT/PC: romp-ibm-aix or rtpc
5650 * New targets supported (not hosts)
5652 AMD 29000 embedded with COFF a29k-none-coff
5653 AMD 29000 embedded with a.out a29k-none-aout
5654 Ultracomputer remote kernel debug a29k-nyu-kern
5656 * New remote interfaces
5662 *** Changes in GDB-4.0:
5666 Wide output is wrapped at good places to make the output more readable.
5668 Gdb now supports cross-debugging from a host machine of one type to a
5669 target machine of another type. Communication with the target system
5670 is over serial lines. The ``target'' command handles connecting to the
5671 remote system; the ``load'' command will download a program into the
5672 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5673 also supports debugging of realtime processes running under VxWorks,
5674 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5675 stub on the target system.
5677 New CPUs supported include the AMD 29000 and Intel 960.
5679 GDB now reads object files and symbol tables via a ``binary file''
5680 library, which allows a single copy of GDB to debug programs of multiple
5681 object file types such as a.out and coff.
5683 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5684 refcard.dvi and refcard.ps are available to format it).
5687 * Control-Variable user interface simplified
5689 All variables that control the operation of the debugger can be set
5690 by the ``set'' command, and displayed by the ``show'' command.
5692 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5693 ``Show prompt'' produces the response:
5694 Gdb's prompt is new-gdb=>.
5696 What follows are the NEW set commands. The command ``help set'' will
5697 print a complete list of old and new set commands. ``help set FOO''
5698 will give a longer description of the variable FOO. ``show'' will show
5699 all of the variable descriptions and their current settings.
5701 confirm on/off: Enables warning questions for operations that are
5702 hard to recover from, e.g. rerunning the program while
5703 it is already running. Default is ON.
5705 editing on/off: Enables EMACS style command line editing
5706 of input. Previous lines can be recalled with
5707 control-P, the current line can be edited with control-B,
5708 you can search for commands with control-R, etc.
5711 history filename NAME: NAME is where the gdb command history
5712 will be stored. The default is .gdb_history,
5713 or the value of the environment variable
5716 history size N: The size, in commands, of the command history. The
5717 default is 256, or the value of the environment variable
5720 history save on/off: If this value is set to ON, the history file will
5721 be saved after exiting gdb. If set to OFF, the
5722 file will not be saved. The default is OFF.
5724 history expansion on/off: If this value is set to ON, then csh-like
5725 history expansion will be performed on
5726 command line input. The default is OFF.
5728 radix N: Sets the default radix for input and output. It can be set
5729 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5730 in the current radix, so "set radix 10" is always a no-op.
5732 height N: This integer value is the number of lines on a page. Default
5733 is 24, the current `stty rows'' setting, or the ``li#''
5734 setting from the termcap entry matching the environment
5737 width N: This integer value is the number of characters on a line.
5738 Default is 80, the current `stty cols'' setting, or the ``co#''
5739 setting from the termcap entry matching the environment
5742 Note: ``set screensize'' is obsolete. Use ``set height'' and
5743 ``set width'' instead.
5745 print address on/off: Print memory addresses in various command displays,
5746 such as stack traces and structure values. Gdb looks
5747 more ``symbolic'' if you turn this off; it looks more
5748 ``machine level'' with it on. Default is ON.
5750 print array on/off: Prettyprint arrays. New convenient format! Default
5753 print demangle on/off: Print C++ symbols in "source" form if on,
5756 print asm-demangle on/off: Same, for assembler level printouts
5759 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5762 * Support for Epoch Environment.
5764 The epoch environment is a version of Emacs v18 with windowing. One
5765 new command, ``inspect'', is identical to ``print'', except that if you
5766 are running in the epoch environment, the value is printed in its own
5770 * Support for Shared Libraries
5772 GDB can now debug programs and core files that use SunOS shared libraries.
5773 Symbols from a shared library cannot be referenced
5774 before the shared library has been linked with the program (this
5775 happens after you type ``run'' and before the function main() is entered).
5776 At any time after this linking (including when examining core files
5777 from dynamically linked programs), gdb reads the symbols from each
5778 shared library when you type the ``sharedlibrary'' command.
5779 It can be abbreviated ``share''.
5781 sharedlibrary REGEXP: Load shared object library symbols for files
5782 matching a unix regular expression. No argument
5783 indicates to load symbols for all shared libraries.
5785 info sharedlibrary: Status of loaded shared libraries.
5790 A watchpoint stops execution of a program whenever the value of an
5791 expression changes. Checking for this slows down execution
5792 tremendously whenever you are in the scope of the expression, but is
5793 quite useful for catching tough ``bit-spreader'' or pointer misuse
5794 problems. Some machines such as the 386 have hardware for doing this
5795 more quickly, and future versions of gdb will use this hardware.
5797 watch EXP: Set a watchpoint (breakpoint) for an expression.
5799 info watchpoints: Information about your watchpoints.
5801 delete N: Deletes watchpoint number N (same as breakpoints).
5802 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5803 enable N: Re-enables watchpoint number N (same as breakpoints).
5806 * C++ multiple inheritance
5808 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5811 * C++ exception handling
5813 Gdb now supports limited C++ exception handling. Besides the existing
5814 ability to breakpoint on an exception handler, gdb can breakpoint on
5815 the raising of an exception (before the stack is peeled back to the
5818 catch FOO: If there is a FOO exception handler in the dynamic scope,
5819 set a breakpoint to catch exceptions which may be raised there.
5820 Multiple exceptions (``catch foo bar baz'') may be caught.
5822 info catch: Lists all exceptions which may be caught in the
5823 current stack frame.
5826 * Minor command changes
5828 The command ``call func (arg, arg, ...)'' now acts like the print
5829 command, except it does not print or save a value if the function's result
5830 is void. This is similar to dbx usage.
5832 The ``up'' and ``down'' commands now always print the frame they end up
5833 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5834 frames without printing.
5836 * New directory command
5838 'dir' now adds directories to the FRONT of the source search path.
5839 The path starts off empty. Source files that contain debug information
5840 about the directory in which they were compiled can be found even
5841 with an empty path; Sun CC and GCC include this information. If GDB can't
5842 find your source file in the current directory, type "dir .".
5844 * Configuring GDB for compilation
5846 For normal use, type ``./configure host''. See README or gdb.texinfo
5849 GDB now handles cross debugging. If you are remotely debugging between
5850 two different machines, type ``./configure host -target=targ''.
5851 Host is the machine where GDB will run; targ is the machine
5852 where the program that you are debugging will run.
projects / external / binutils.git / blob