1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.8
6 * GDB now supports hardware watchpoints on x86 GNU Hurd.
10 ** You can now access frame registers from Python scripts.
11 ** New attribute 'producer' for gdb.Symtab objects.
12 ** gdb.Objfile objects have a new attribute "progspace",
13 which is the gdb.Progspace object of the containing program space.
14 ** A new event "gdb.clear_objfiles" has been added, triggered when
15 selecting a new file to debug.
16 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
18 * New Python-based convenience functions:
20 ** $_caller_is(name [, number_of_frames])
21 ** $_caller_matches(regexp [, number_of_frames])
22 ** $_any_caller_is(name [, number_of_frames])
23 ** $_any_caller_matches(regexp [, number_of_frames])
27 queue-signal signal-name-or-number
28 Queue a signal to be delivered to the thread when it is resumed.
30 add-auto-load-scripts-directory directory
31 Add entries to the list of directories from which to load auto-loaded
34 * On resume, GDB now always passes the signal the program had stopped
35 for to the thread the signal was sent to, even if the user changed
36 threads before resuming. Previously GDB would often (but not
37 always) deliver the signal to the thread that happens to be current
40 * Conversely, the "signal" command now consistently delivers the
41 requested signal to the current thread. GDB now asks for
42 confirmation if the program had stopped for a signal and the user
43 switched threads meanwhile.
45 * "breakpoint always-inserted" modes "off" and "auto" merged.
47 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
48 won't remove breakpoints from the target until all threads stop,
49 even in non-stop mode. The "auto" mode has been removed, and "off"
50 is now the default mode.
54 ** The -list-thread-groups command outputs an exit-code field for
55 inferiors that have exited.
59 Support for these obsolete configurations has been removed.
61 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
62 SGI Irix-5.x mips-*-irix5*
63 SGI Irix-6.x mips-*-irix6*
64 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
65 VAX running Ultrix vax-*-ultrix*
67 *** Changes in GDB 7.8
69 * New command line options
72 This is an alias for the --data-directory option.
74 * GDB supports printing and modifying of variable length automatic arrays
75 as specified in ISO C99.
77 * The ARM simulator now supports instruction level tracing
78 with or without disassembly.
82 GDB now has support for scripting using Guile. Whether this is
83 available is determined at configure time.
84 Guile version 2.0 or greater is required.
85 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
87 * New commands (for set/show, see "New options" below)
91 Invoke CODE by passing it to the Guile interpreter.
95 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
97 info auto-load guile-scripts [regexp]
98 Print the list of automatically loaded Guile scripts.
100 * The source command is now capable of sourcing Guile scripts.
101 This feature is dependent on the debugger being built with Guile support.
105 set print symbol-loading (off|brief|full)
106 show print symbol-loading
107 Control whether to print informational messages when loading symbol
108 information for a file. The default is "full", but when debugging
109 programs with large numbers of shared libraries the amount of output
112 set guile print-stack (none|message|full)
113 show guile print-stack
114 Show a stack trace when an error is encountered in a Guile script.
116 set auto-load guile-scripts (on|off)
117 show auto-load guile-scripts
118 Control auto-loading of Guile script files.
120 maint ada set ignore-descriptive-types (on|off)
121 maint ada show ignore-descriptive-types
122 Control whether the debugger should ignore descriptive types in Ada
123 programs. The default is not to ignore the descriptive types. See
124 the user manual for more details on descriptive types and the intended
125 usage of this option.
127 set auto-connect-native-target
129 Control whether GDB is allowed to automatically connect to the
130 native target for the run, attach, etc. commands when not connected
131 to any target yet. See also "target native" below.
133 set record btrace replay-memory-access (read-only|read-write)
134 show record btrace replay-memory-access
135 Control what memory accesses are allowed during replay.
137 maint set target-async (on|off)
138 maint show target-async
139 This controls whether GDB targets operate in synchronous or
140 asynchronous mode. Normally the default is asynchronous, if it is
141 available; but this can be changed to more easily debug problems
142 occurring only in synchronous mode.
144 set mi-async (on|off)
146 Control whether MI asynchronous mode is preferred. This supersedes
147 "set target-async" of previous GDB versions.
149 * "set target-async" is deprecated as a CLI option and is now an alias
150 for "set mi-async" (only puts MI into async mode).
152 * Background execution commands (e.g., "c&", "s&", etc.) are now
153 possible ``out of the box'' if the target supports them. Previously
154 the user would need to explicitly enable the possibility with the
155 "set target-async on" command.
157 * New features in the GDB remote stub, GDBserver
159 ** New option --debug-format=option1[,option2,...] allows one to add
160 additional text to each output. At present only timestamps
161 are supported: --debug-format=timestamps.
162 Timestamps can also be turned on with the
163 "monitor set debug-format timestamps" command from GDB.
165 * The 'record instruction-history' command now starts counting instructions
166 at one. This also affects the instruction ranges reported by the
167 'record function-call-history' command when given the /i modifier.
169 * The command 'record function-call-history' supports a new modifier '/c' to
170 indent the function names based on their call stack depth.
171 The fields for the '/i' and '/l' modifier have been reordered.
172 The source line range is now prefixed with 'at'.
173 The instruction range is now prefixed with 'inst'.
174 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
175 "record instruction-history" and "list" commands.
177 * The ranges given as arguments to the 'record function-call-history' and
178 'record instruction-history' commands are now inclusive.
180 * The btrace record target now supports the 'record goto' command.
181 For locations inside the execution trace, the back trace is computed
182 based on the information stored in the execution trace.
184 * The btrace record target supports limited reverse execution and replay.
185 The target does not record data and therefore does not allow reading
188 * The "catch syscall" command now works on s390*-linux* targets.
190 * The "compare-sections" command is no longer specific to target
191 remote. It now works with all targets.
193 * All native targets are now consistently called "native".
194 Consequently, the "target child", "target GNU", "target djgpp",
195 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
196 commands have been replaced with "target native". The QNX/NTO port
197 leaves the "procfs" target in place and adds a "native" target for
198 consistency with other ports. The impact on users should be minimal
199 as these commands previously either throwed an error, or were
200 no-ops. The target's name is visible in the output of the following
201 commands: "help target", "info target", "info files", "maint print
204 * The "target native" command now connects to the native target. This
205 can be used to launch native programs even when "set
206 auto-connect-native-target" is set to off.
208 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
210 * Support for Intel(R) AVX-512 registers on GNU/Linux.
211 Support displaying and modifying Intel(R) AVX-512 registers
212 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
216 qXfer:btrace:read's annex
217 The qXfer:btrace:read packet supports a new annex 'delta' to read
218 branch trace incrementally.
222 ** Valid Python operations on gdb.Value objects representing
223 structs/classes invoke the corresponding overloaded operators if
225 ** New `Xmethods' feature in the Python API. Xmethods are
226 additional methods or replacements for existing methods of a C++
227 class. This feature is useful for those cases where a method
228 defined in C++ source code could be inlined or optimized out by
229 the compiler, making it unavailable to GDB.
232 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
234 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
235 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
236 its alias "share", instead.
238 * The commands "set remotebaud" and "show remotebaud" are no longer
239 supported. Use "set serial baud" and "show serial baud" (respectively)
244 ** A new option "-gdb-set mi-async" replaces "-gdb-set
245 target-async". The latter is left as a deprecated alias of the
246 former for backward compatibility. If the target supports it,
247 CLI background execution commands are now always possible by
248 default, independently of whether the frontend stated a
249 preference for asynchronous execution with "-gdb-set mi-async".
250 Previously "-gdb-set target-async off" affected both MI execution
251 commands and CLI execution commands.
253 *** Changes in GDB 7.7
255 * Improved support for process record-replay and reverse debugging on
256 arm*-linux* targets. Support for thumb32 and syscall instruction
257 recording has been added.
259 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
261 * GDB now supports Fission DWP file format version 2.
262 http://gcc.gnu.org/wiki/DebugFission
264 * New convenience function "$_isvoid", to check whether an expression
265 is void. A void expression is an expression where the type of the
266 result is "void". For example, some convenience variables may be
267 "void" when evaluated (e.g., "$_exitcode" before the execution of
268 the program being debugged; or an undefined convenience variable).
269 Another example, when calling a function whose return type is
272 * The "maintenance print objfiles" command now takes an optional regexp.
274 * The "catch syscall" command now works on arm*-linux* targets.
276 * GDB now consistently shows "<not saved>" when printing values of
277 registers the debug info indicates have not been saved in the frame
278 and there's nowhere to retrieve them from
279 (callee-saved/call-clobbered registers):
284 (gdb) info registers rax
287 Before, the former would print "<optimized out>", and the latter
288 "*value not available*".
290 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
295 ** Frame filters and frame decorators have been added.
296 ** Temporary breakpoints are now supported.
297 ** Line tables representation has been added.
298 ** New attribute 'parent_type' for gdb.Field objects.
299 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
300 ** New attribute 'name' for gdb.Type objects.
304 Nios II ELF nios2*-*-elf
305 Nios II GNU/Linux nios2*-*-linux
306 Texas Instruments MSP430 msp430*-*-elf
308 * Removed native configurations
310 Support for these a.out NetBSD and OpenBSD obsolete configurations has
311 been removed. ELF variants of these configurations are kept supported.
313 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
314 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
315 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
316 i[34567]86-*-openbsd3.[0-3]
317 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
318 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
319 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
323 Like "catch throw", but catches a re-thrown exception.
325 Renamed from old "maint check-symtabs".
327 Perform consistency checks on symtabs.
329 Expand symtabs matching an optional regexp.
332 Display the details of GDB configure-time options.
334 maint set|show per-command
335 maint set|show per-command space
336 maint set|show per-command time
337 maint set|show per-command symtab
338 Enable display of per-command gdb resource usage.
340 remove-symbol-file FILENAME
341 remove-symbol-file -a ADDRESS
342 Remove a symbol file added via add-symbol-file. The file to remove
343 can be identified by its filename or by an address that lies within
344 the boundaries of this symbol file in memory.
347 info exceptions REGEXP
348 Display the list of Ada exceptions defined in the program being
349 debugged. If provided, only the exceptions whose names match REGEXP
354 set debug symfile off|on
356 Control display of debugging info regarding reading symbol files and
357 symbol tables within those files
359 set print raw frame-arguments
360 show print raw frame-arguments
361 Set/show whether to print frame arguments in raw mode,
362 disregarding any defined pretty-printers.
364 set remote trace-status-packet
365 show remote trace-status-packet
366 Set/show the use of remote protocol qTStatus packet.
370 Control display of debugging messages related to Nios II targets.
374 Control whether target-assisted range stepping is enabled.
376 set startup-with-shell
377 show startup-with-shell
378 Specifies whether Unix child processes are started via a shell or
383 Use the target memory cache for accesses to the code segment. This
384 improves performance of remote debugging (particularly disassembly).
386 * You can now use a literal value 'unlimited' for options that
387 interpret 0 or -1 as meaning "unlimited". E.g., "set
388 trace-buffer-size unlimited" is now an alias for "set
389 trace-buffer-size -1" and "set height unlimited" is now an alias for
392 * The "set debug symtab-create" debugging option of GDB has been changed to
393 accept a verbosity level. 0 means "off", 1 provides basic debugging
394 output, and values of 2 or greater provides more verbose output.
396 * New command-line options
398 Display the details of GDB configure-time options.
400 * The command 'tsave' can now support new option '-ctf' to save trace
401 buffer in Common Trace Format.
403 * Newly installed $prefix/bin/gcore acts as a shell interface for the
406 * GDB now implements the the C++ 'typeid' operator.
408 * The new convenience variable $_exception holds the exception being
409 thrown or caught at an exception-related catchpoint.
411 * The exception-related catchpoints, like "catch throw", now accept a
412 regular expression which can be used to filter exceptions by type.
414 * The new convenience variable $_exitsignal is automatically set to
415 the terminating signal number when the program being debugged dies
416 due to an uncaught signal.
420 ** All MI commands now accept an optional "--language" option.
421 Support for this feature can be verified by using the "-list-features"
422 command, which should contain "language-option".
424 ** The new command -info-gdb-mi-command allows the user to determine
425 whether a GDB/MI command is supported or not.
427 ** The "^error" result record returned when trying to execute an undefined
428 GDB/MI command now provides a variable named "code" whose content is the
429 "undefined-command" error code. Support for this feature can be verified
430 by using the "-list-features" command, which should contain
431 "undefined-command-error-code".
433 ** The -trace-save MI command can optionally save trace buffer in Common
436 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
438 ** The command -data-list-register-values now accepts an optional
439 "--skip-unavailable" option. When used, only the available registers
442 ** The new command -trace-frame-collected dumps collected variables,
443 computed expressions, tvars, memory and registers in a traceframe.
445 ** The commands -stack-list-locals, -stack-list-arguments and
446 -stack-list-variables now accept an option "--skip-unavailable".
447 When used, only the available locals or arguments are displayed.
449 ** The -exec-run command now accepts an optional "--start" option.
450 When used, the command follows the same semantics as the "start"
451 command, stopping the program's execution at the start of its
452 main subprogram. Support for this feature can be verified using
453 the "-list-features" command, which should contain
454 "exec-run-start-option".
456 ** The new commands -catch-assert and -catch-exceptions insert
457 catchpoints stopping the program when Ada exceptions are raised.
459 ** The new command -info-ada-exceptions provides the equivalent of
460 the new "info exceptions" command.
462 * New system-wide configuration scripts
463 A GDB installation now provides scripts suitable for use as system-wide
464 configuration scripts for the following systems:
468 * GDB now supports target-assigned range stepping with remote targets.
469 This improves the performance of stepping source lines by reducing
470 the number of control packets from/to GDB. See "New remote packets"
473 * GDB now understands the element 'tvar' in the XML traceframe info.
474 It has the id of the collected trace state variables.
476 * On S/390 targets that provide the transactional-execution feature,
477 the program interruption transaction diagnostic block (TDB) is now
478 represented as a number of additional "registers" in GDB.
484 The vCont packet supports a new 'r' action, that tells the remote
485 stub to step through an address range itself, without GDB
486 involvemement at each single-step.
488 qXfer:libraries-svr4:read's annex
489 The previously unused annex of the qXfer:libraries-svr4:read packet
490 is now used to support passing an argument list. The remote stub
491 reports support for this argument list to GDB's qSupported query.
492 The defined arguments are "start" and "prev", used to reduce work
493 necessary for library list updating, resulting in significant
496 * New features in the GDB remote stub, GDBserver
498 ** GDBserver now supports target-assisted range stepping. Currently
499 enabled on x86/x86_64 GNU/Linux targets.
501 ** GDBserver now adds element 'tvar' in the XML in the reply to
502 'qXfer:traceframe-info:read'. It has the id of the collected
503 trace state variables.
505 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
508 * New 'z' formatter for printing and examining memory, this displays the
509 value as hexadecimal zero padded on the left to the size of the type.
511 * GDB can now use Windows x64 unwinding data.
513 * The "set remotebaud" command has been replaced by "set serial baud".
514 Similarly, "show remotebaud" has been replaced by "show serial baud".
515 The "set remotebaud" and "show remotebaud" commands are still available
516 to provide backward compatibility with older versions of GDB.
518 *** Changes in GDB 7.6
520 * Target record has been renamed to record-full.
521 Record/replay is now enabled with the "record full" command.
522 This also affects settings that are associated with full record/replay
523 that have been moved from "set/show record" to "set/show record full":
525 set|show record full insn-number-max
526 set|show record full stop-at-limit
527 set|show record full memory-query
529 * A new record target "record-btrace" has been added. The new target
530 uses hardware support to record the control-flow of a process. It
531 does not support replaying the execution, but it implements the
532 below new commands for investigating the recorded execution log.
533 This new recording method can be enabled using:
537 The "record-btrace" target is only available on Intel Atom processors
538 and requires a Linux kernel 2.6.32 or later.
540 * Two new commands have been added for record/replay to give information
541 about the recorded execution without having to replay the execution.
542 The commands are only supported by "record btrace".
544 record instruction-history prints the execution history at
545 instruction granularity
547 record function-call-history prints the execution history at
550 * New native configurations
552 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
553 FreeBSD/powerpc powerpc*-*-freebsd
554 x86_64/Cygwin x86_64-*-cygwin*
555 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
559 ARM AArch64 aarch64*-*-elf
560 ARM AArch64 GNU/Linux aarch64*-*-linux
561 Lynx 178 PowerPC powerpc-*-lynx*178
562 x86_64/Cygwin x86_64-*-cygwin*
563 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
565 * If the configured location of system.gdbinit file (as given by the
566 --with-system-gdbinit option at configure time) is in the
567 data-directory (as specified by --with-gdb-datadir at configure
568 time) or in one of its subdirectories, then GDB will look for the
569 system-wide init file in the directory specified by the
570 --data-directory command-line option.
572 * New command line options:
574 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
575 other initialization files, unlike -nx which disables all of them.
577 * Removed command line options
579 -epoch This was used by the gdb mode in Epoch, an ancient fork of
582 * The 'ptype' and 'whatis' commands now accept an argument to control
585 * 'info proc' now works on some core files.
589 ** Vectors can be created with gdb.Type.vector.
591 ** Python's atexit.register now works in GDB.
593 ** Types can be pretty-printed via a Python API.
595 ** Python 3 is now supported (in addition to Python 2.4 or later)
597 ** New class gdb.Architecture exposes GDB's internal representation
598 of architecture in the Python API.
600 ** New method Frame.architecture returns the gdb.Architecture object
601 corresponding to the frame's architecture.
603 * New Python-based convenience functions:
605 ** $_memeq(buf1, buf2, length)
606 ** $_streq(str1, str2)
608 ** $_regex(str, regex)
610 * The 'cd' command now defaults to using '~' (the home directory) if not
613 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
614 default for GCC since November 2000.
616 * The command 'forward-search' can now be abbreviated as 'fo'.
618 * The command 'info tracepoints' can now display 'installed on target'
619 or 'not installed on target' for each non-pending location of tracepoint.
621 * New configure options
623 --enable-libmcheck/--disable-libmcheck
624 By default, development versions are built with -lmcheck on hosts
625 that support it, in order to help track memory corruption issues.
626 Release versions, on the other hand, are built without -lmcheck
627 by default. The --enable-libmcheck/--disable-libmcheck configure
628 options allow the user to override that default.
629 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
630 This configure option allows the user to build GDB with
631 libbabeltrace using which GDB can read Common Trace Format data.
633 * New commands (for set/show, see "New options" below)
636 Catch signals. This is similar to "handle", but allows commands and
637 conditions to be attached.
640 List the BFDs known to GDB.
642 python-interactive [command]
644 Start a Python interactive prompt, or evaluate the optional command
645 and print the result of expressions.
648 "py" is a new alias for "python".
650 enable type-printer [name]...
651 disable type-printer [name]...
652 Enable or disable type printers.
656 ** For the Renesas Super-H architecture, the "regs" command has been removed
657 (has been deprecated in GDB 7.5), and "info all-registers" should be used
662 set print type methods (on|off)
663 show print type methods
664 Control whether method declarations are displayed by "ptype".
665 The default is to show them.
667 set print type typedefs (on|off)
668 show print type typedefs
669 Control whether typedef definitions are displayed by "ptype".
670 The default is to show them.
672 set filename-display basename|relative|absolute
673 show filename-display
674 Control the way in which filenames is displayed.
675 The default is "relative", which preserves previous behavior.
677 set trace-buffer-size
678 show trace-buffer-size
679 Request target to change the size of trace buffer.
681 set remote trace-buffer-size-packet auto|on|off
682 show remote trace-buffer-size-packet
683 Control the use of the remote protocol `QTBuffer:size' packet.
687 Control display of debugging messages related to ARM AArch64.
690 set debug coff-pe-read
691 show debug coff-pe-read
692 Control display of debugging messages related to reading of COFF/PE
697 Control display of debugging messages related to Mach-O symbols
700 set debug notification
701 show debug notification
702 Control display of debugging info for async remote notification.
706 ** Command parameter changes are now notified using new async record
707 "=cmd-param-changed".
708 ** Trace frame changes caused by command "tfind" are now notified using
709 new async record "=traceframe-changed".
710 ** The creation, deletion and modification of trace state variables
711 are now notified using new async records "=tsv-created",
712 "=tsv-deleted" and "=tsv-modified".
713 ** The start and stop of process record are now notified using new
714 async record "=record-started" and "=record-stopped".
715 ** Memory changes are now notified using new async record
717 ** The data-disassemble command response will include a "fullname" field
718 containing the absolute file name when source has been requested.
719 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
720 command, to allow pattern filling of memory areas.
721 ** New commands "-catch-load"/"-catch-unload" added for intercepting
722 library load/unload events.
723 ** The response to breakpoint commands and breakpoint async records
724 includes an "installed" field containing a boolean state about each
725 non-pending tracepoint location is whether installed on target or not.
726 ** Output of the "-trace-status" command includes a "trace-file" field
727 containing the name of the trace file being examined. This field is
728 optional, and only present when examining a trace file.
729 ** The "fullname" field is now always present along with the "file" field,
730 even if the file cannot be found by GDB.
732 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
733 You must have the LZMA library available when configuring GDB for this
734 feature to be enabled. For more information, see:
735 http://fedoraproject.org/wiki/Features/MiniDebugInfo
740 Set the size of trace buffer. The remote stub reports support for this
741 packet to gdb's qSupported query.
744 Enable Branch Trace Store (BTS)-based branch tracing for the current
745 thread. The remote stub reports support for this packet to gdb's
749 Disable branch tracing for the current thread. The remote stub reports
750 support for this packet to gdb's qSupported query.
753 Read the traced branches for the current thread. The remote stub
754 reports support for this packet to gdb's qSupported query.
756 *** Changes in GDB 7.5
758 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
759 for more x32 ABI info.
761 * GDB now supports access to MIPS DSP registers on Linux targets.
763 * GDB now supports debugging microMIPS binaries.
765 * The "info os" command on GNU/Linux can now display information on
766 several new classes of objects managed by the operating system:
767 "info os procgroups" lists process groups
768 "info os files" lists file descriptors
769 "info os sockets" lists internet-domain sockets
770 "info os shm" lists shared-memory regions
771 "info os semaphores" lists semaphores
772 "info os msg" lists message queues
773 "info os modules" lists loaded kernel modules
775 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
776 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
777 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
778 options and inspect the probe arguments using the new $_probe_arg family
779 of convenience variables. You can obtain more information about SystemTap
780 in <http://sourceware.org/systemtap/>.
782 * GDB now supports reversible debugging on ARM, it allows you to
783 debug basic ARM and THUMB instructions, and provides
784 record/replay support.
786 * The option "symbol-reloading" has been deleted as it is no longer used.
790 ** GDB commands implemented in Python can now be put in command class
793 ** The "maint set python print-stack on|off" is now deleted.
795 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
796 apply "flag enum"-style pretty-printing to any enum.
798 ** gdb.lookup_symbol can now work when there is no current frame.
800 ** gdb.Symbol now has a 'line' attribute, holding the line number in
801 the source at which the symbol was defined.
803 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
804 method 'value'. The former indicates whether the symbol needs a
805 frame in order to compute its value, and the latter computes the
808 ** A new method 'referenced_value' on gdb.Value objects which can
809 dereference pointer as well as C++ reference values.
811 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
812 which return the global and static blocks (as gdb.Block objects),
813 of the underlying symbol table, respectively.
815 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
816 object associated with a PC value.
818 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
819 of the address range occupied by code for the current source line.
821 * Go language support.
822 GDB now supports debugging programs written in the Go programming
825 * GDBserver now supports stdio connections.
826 E.g. (gdb) target remote | ssh myhost gdbserver - hello
828 * The binary "gdbtui" can no longer be built or installed.
829 Use "gdb -tui" instead.
831 * GDB will now print "flag" enums specially. A flag enum is one where
832 all the enumerator values have no bits in common when pairwise
833 "and"ed. When printing a value whose type is a flag enum, GDB will
834 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
835 (gdb) print (enum E) 3
838 * The filename part of a linespec will now match trailing components
839 of a source file name. For example, "break gcc/expr.c:1000" will
840 now set a breakpoint in build/gcc/expr.c, but not
843 * The "info proc" and "generate-core-file" commands will now also
844 work on remote targets connected to GDBserver on Linux.
846 * The command "info catch" has been removed. It has been disabled
849 * The "catch exception" and "catch assert" commands now accept
850 a condition at the end of the command, much like the "break"
851 command does. For instance:
853 (gdb) catch exception Constraint_Error if Barrier = True
855 Previously, it was possible to add a condition to such catchpoints,
856 but it had to be done as a second step, after the catchpoint had been
857 created, using the "condition" command.
859 * The "info static-tracepoint-marker" command will now also work on
860 native Linux targets with in-process agent.
862 * GDB can now set breakpoints on inlined functions.
864 * The .gdb_index section has been updated to include symbols for
865 inlined functions. GDB will ignore older .gdb_index sections by
866 default, which could cause symbol files to be loaded more slowly
867 until their .gdb_index sections can be recreated. The new command
868 "set use-deprecated-index-sections on" will cause GDB to use any older
869 .gdb_index sections it finds. This will restore performance, but the
870 ability to set breakpoints on inlined functions will be lost in symbol
871 files with older .gdb_index sections.
873 The .gdb_index section has also been updated to record more information
874 about each symbol. This speeds up the "info variables", "info functions"
875 and "info types" commands when used with programs having the .gdb_index
876 section, as well as speeding up debugging with shared libraries using
877 the .gdb_index section.
879 * Ada support for GDB/MI Variable Objects has been added.
881 * GDB can now support 'breakpoint always-inserted mode' in 'record'
886 ** New command -info-os is the MI equivalent of "info os".
888 ** Output logs ("set logging" and related) now include MI output.
892 ** "set use-deprecated-index-sections on|off"
893 "show use-deprecated-index-sections on|off"
894 Controls the use of deprecated .gdb_index sections.
896 ** "catch load" and "catch unload" can be used to stop when a shared
897 library is loaded or unloaded, respectively.
899 ** "enable count" can be used to auto-disable a breakpoint after
902 ** "info vtbl" can be used to show the virtual method tables for
903 C++ and Java objects.
905 ** "explore" and its sub commands "explore value" and "explore type"
906 can be used to recursively explore values and types of
907 expressions. These commands are available only if GDB is
908 configured with '--with-python'.
910 ** "info auto-load" shows status of all kinds of auto-loaded files,
911 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
912 sequences of commands files, "info auto-load python-scripts"
913 shows status of auto-loading Python script files,
914 "info auto-load local-gdbinit" shows status of loading init file
915 (.gdbinit) from current directory and "info auto-load libthread-db" shows
916 status of inferior specific thread debugging shared library loading.
918 ** "info auto-load-scripts", "set auto-load-scripts on|off"
919 and "show auto-load-scripts" commands have been deprecated, use their
920 "info auto-load python-scripts", "set auto-load python-scripts on|off"
921 and "show auto-load python-scripts" counterparts instead.
923 ** "dprintf location,format,args..." creates a dynamic printf, which
924 is basically a breakpoint that does a printf and immediately
925 resumes your program's execution, so it is like a printf that you
926 can insert dynamically at runtime instead of at compiletime.
928 ** "set print symbol"
930 Controls whether GDB attempts to display the symbol, if any,
931 corresponding to addresses it prints. This defaults to "on", but
932 you can set it to "off" to restore GDB's previous behavior.
934 * Deprecated commands
936 ** For the Renesas Super-H architecture, the "regs" command has been
937 deprecated, and "info all-registers" should be used instead.
941 Renesas RL78 rl78-*-elf
942 HP OpenVMS ia64 ia64-hp-openvms*
944 * GDBserver supports evaluation of breakpoint conditions. When
945 support is advertised by GDBserver, GDB may be told to send the
946 breakpoint conditions in bytecode form to GDBserver. GDBserver
947 will only report the breakpoint trigger to GDB when its condition
953 show mips compression
954 Select the compressed ISA encoding used in functions that have no symbol
955 information available. The encoding can be set to either of:
958 and is updated automatically from ELF file flags if available.
960 set breakpoint condition-evaluation
961 show breakpoint condition-evaluation
962 Control whether breakpoint conditions are evaluated by GDB ("host") or by
963 GDBserver ("target"). Default option "auto" chooses the most efficient
965 This option can improve debugger efficiency depending on the speed of the
969 Disable auto-loading globally.
972 Show auto-loading setting of all kinds of auto-loaded files.
974 set auto-load gdb-scripts on|off
975 show auto-load gdb-scripts
976 Control auto-loading of GDB canned sequences of commands files.
978 set auto-load python-scripts on|off
979 show auto-load python-scripts
980 Control auto-loading of Python script files.
982 set auto-load local-gdbinit on|off
983 show auto-load local-gdbinit
984 Control loading of init file (.gdbinit) from current directory.
986 set auto-load libthread-db on|off
987 show auto-load libthread-db
988 Control auto-loading of inferior specific thread debugging shared library.
990 set auto-load scripts-directory <dir1>[:<dir2>...]
991 show auto-load scripts-directory
992 Set a list of directories from which to load auto-loaded scripts.
993 Automatically loaded Python scripts and GDB scripts are located in one
994 of the directories listed by this option.
995 The delimiter (':' above) may differ according to the host platform.
997 set auto-load safe-path <dir1>[:<dir2>...]
998 show auto-load safe-path
999 Set a list of directories from which it is safe to auto-load files.
1000 The delimiter (':' above) may differ according to the host platform.
1002 set debug auto-load on|off
1003 show debug auto-load
1004 Control display of debugging info for auto-loading the files above.
1006 set dprintf-style gdb|call|agent
1008 Control the way in which a dynamic printf is performed; "gdb"
1009 requests a GDB printf command, while "call" causes dprintf to call a
1010 function in the inferior. "agent" requests that the target agent
1011 (such as GDBserver) do the printing.
1013 set dprintf-function <expr>
1014 show dprintf-function
1015 set dprintf-channel <expr>
1016 show dprintf-channel
1017 Set the function and optional first argument to the call when using
1018 the "call" style of dynamic printf.
1020 set disconnected-dprintf on|off
1021 show disconnected-dprintf
1022 Control whether agent-style dynamic printfs continue to be in effect
1023 after GDB disconnects.
1025 * New configure options
1027 --with-auto-load-dir
1028 Configure default value for the 'set auto-load scripts-directory'
1029 setting above. It defaults to '$debugdir:$datadir/auto-load',
1030 $debugdir representing global debugging info directories (available
1031 via 'show debug-file-directory') and $datadir representing GDB's data
1032 directory (available via 'show data-directory').
1034 --with-auto-load-safe-path
1035 Configure default value for the 'set auto-load safe-path' setting
1036 above. It defaults to the --with-auto-load-dir setting.
1038 --without-auto-load-safe-path
1039 Set 'set auto-load safe-path' to '/', effectively disabling this
1042 * New remote packets
1044 z0/z1 conditional breakpoints extension
1046 The z0/z1 breakpoint insertion packets have been extended to carry
1047 a list of conditional expressions over to the remote stub depending on the
1048 condition evaluation mode. The use of this extension can be controlled
1049 via the "set remote conditional-breakpoints-packet" command.
1053 Specify the signals which the remote stub may pass to the debugged
1054 program without GDB involvement.
1056 * New command line options
1058 --init-command=FILE, -ix Like --command, -x but execute it
1059 before loading inferior.
1060 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1061 execute it before loading inferior.
1063 *** Changes in GDB 7.4
1065 * GDB now handles ambiguous linespecs more consistently; the existing
1066 FILE:LINE support has been expanded to other types of linespecs. A
1067 breakpoint will now be set on all matching locations in all
1068 inferiors, and locations will be added or removed according to
1071 * GDB now allows you to skip uninteresting functions and files when
1072 stepping with the "skip function" and "skip file" commands.
1074 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1075 and "show remote hardware-watchpoint-length-limit". These allows to
1076 set or show the maximum length limit (in bytes) of a remote
1077 target hardware watchpoint.
1079 This allows e.g. to use "unlimited" hardware watchpoints with the
1080 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1081 watchpoints are slower than real hardware watchpoints but are
1082 significantly faster than gdb software watchpoints.
1086 ** The register_pretty_printer function in module gdb.printing now takes
1087 an optional `replace' argument. If True, the new printer replaces any
1090 ** The "maint set python print-stack on|off" command has been
1091 deprecated and will be deleted in GDB 7.5.
1092 A new command: "set python print-stack none|full|message" has
1093 replaced it. Additionally, the default for "print-stack" is
1094 now "message", which just prints the error message without
1097 ** A prompt substitution hook (prompt_hook) is now available to the
1100 ** A new Python module, gdb.prompt has been added to the GDB Python
1101 modules library. This module provides functionality for
1102 escape sequences in prompts (used by set/show
1103 extended-prompt). These escape sequences are replaced by their
1104 corresponding value.
1106 ** Python commands and convenience-functions located in
1107 'data-directory'/python/gdb/command and
1108 'data-directory'/python/gdb/function are now automatically loaded
1111 ** Blocks now provide four new attributes. global_block and
1112 static_block will return the global and static blocks
1113 respectively. is_static and is_global are boolean attributes
1114 that indicate if the block is one of those two types.
1116 ** Symbols now provide the "type" attribute, the type of the symbol.
1118 ** The "gdb.breakpoint" function has been deprecated in favor of
1121 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1122 of a function. This class is based on the "finish" command
1123 available in the CLI.
1125 ** Type objects for struct and union types now allow access to
1126 the fields using standard Python dictionary (mapping) methods.
1127 For example, "some_type['myfield']" now works, as does
1128 "some_type.items()".
1130 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1133 ** A new function, "deep_items" has been added to the gdb.types
1134 module in the GDB Python modules library. This function returns
1135 an iterator over the fields of a struct or union type. Unlike
1136 the standard Python "iteritems" method, it will recursively traverse
1137 any anonymous fields.
1141 ** "*stopped" events can report several new "reason"s, such as
1144 ** Breakpoint changes are now notified using new async records, like
1145 "=breakpoint-modified".
1147 ** New command -ada-task-info.
1149 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1150 $sdir specifies the default system locations of shared libraries.
1151 $pdir specifies the directory where the libpthread used by the application
1154 GDB no longer looks in $sdir and $pdir after it has searched the directories
1155 mentioned in libthread-db-search-path. If you want to search those
1156 directories, they must be specified in libthread-db-search-path.
1157 The default value of libthread-db-search-path on GNU/Linux and Solaris
1158 systems is now "$sdir:$pdir".
1160 $pdir is not supported by gdbserver, it is currently ignored.
1161 $sdir is supported by gdbserver.
1163 * New configure option --with-iconv-bin.
1164 When using the internationalization support like the one in the GNU C
1165 library, GDB will invoke the "iconv" program to get a list of supported
1166 character sets. If this program lives in a non-standard location, one can
1167 use this option to specify where to find it.
1169 * When natively debugging programs on PowerPC BookE processors running
1170 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1171 watchpoints, which specify a mask in addition to an address to watch.
1172 The mask specifies that some bits of an address (the bits which are
1173 reset in the mask) should be ignored when matching the address accessed
1174 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1175 section in the user manual for more details.
1177 * The new option --once causes GDBserver to stop listening for connections once
1178 the first connection is made. The listening port used by GDBserver will
1179 become available after that.
1181 * New commands "info macros" and "alias" have been added.
1183 * New function parameters suffix @entry specifies value of function parameter
1184 at the time the function got called. Entry values are available only since
1190 "!" is now an alias of the "shell" command.
1191 Note that no space is needed between "!" and SHELL COMMAND.
1195 watch EXPRESSION mask MASK_VALUE
1196 The watch command now supports the mask argument which allows creation
1197 of masked watchpoints, if the current architecture supports this feature.
1199 info auto-load-scripts [REGEXP]
1200 This command was formerly named "maintenance print section-scripts".
1201 It is now generally useful and is no longer a maintenance-only command.
1203 info macro [-all] [--] MACRO
1204 The info macro command has new options `-all' and `--'. The first for
1205 printing all definitions of a macro. The second for explicitly specifying
1206 the end of arguments and the beginning of the macro name in case the macro
1207 name starts with a hyphen.
1209 collect[/s] EXPRESSIONS
1210 The tracepoint collect command now takes an optional modifier "/s"
1211 that directs it to dereference pointer-to-character types and
1212 collect the bytes of memory up to a zero byte. The behavior is
1213 similar to what you see when you use the regular print command on a
1214 string. An optional integer following the "/s" sets a bound on the
1215 number of bytes that will be collected.
1218 The trace start command now interprets any supplied arguments as a
1219 note to be recorded with the trace run, with an effect similar to
1220 setting the variable trace-notes.
1223 The trace stop command now interprets any arguments as a note to be
1224 mentioned along with the tstatus report that the trace was stopped
1225 with a command. The effect is similar to setting the variable
1228 * Tracepoints can now be enabled and disabled at any time after a trace
1229 experiment has been started using the standard "enable" and "disable"
1230 commands. It is now possible to start a trace experiment with no enabled
1231 tracepoints; GDB will display a warning, but will allow the experiment to
1232 begin, assuming that tracepoints will be enabled as needed while the trace
1235 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1236 locations with 4-byte instructions, when they were previously
1237 limited to locations with instructions of 5 bytes or longer.
1241 set debug dwarf2-read
1242 show debug dwarf2-read
1243 Turns on or off display of debugging messages related to reading
1244 DWARF debug info. The default is off.
1246 set debug symtab-create
1247 show debug symtab-create
1248 Turns on or off display of debugging messages related to symbol table
1249 creation. The default is off.
1252 show extended-prompt
1253 Set the GDB prompt, and allow escape sequences to be inserted to
1254 display miscellaneous information (see 'help set extended-prompt'
1255 for the list of sequences). This prompt (and any information
1256 accessed through the escape sequences) is updated every time the
1257 prompt is displayed.
1259 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1260 show print entry-values
1261 Set printing of frame argument values at function entry. In some cases
1262 GDB can determine the value of function argument which was passed by the
1263 function caller, even if the value was modified inside the called function.
1265 set debug entry-values
1266 show debug entry-values
1267 Control display of debugging info for determining frame argument values at
1268 function entry and virtual tail call frames.
1270 set basenames-may-differ
1271 show basenames-may-differ
1272 Set whether a source file may have multiple base names.
1273 (A "base name" is the name of a file with the directory part removed.
1274 Example: The base name of "/home/user/hello.c" is "hello.c".)
1275 If set, GDB will canonicalize file names (e.g., expand symlinks)
1276 before comparing them. Canonicalization is an expensive operation,
1277 but it allows the same file be known by more than one base name.
1278 If not set (the default), all source files are assumed to have just
1279 one base name, and gdb will do file name comparisons more efficiently.
1285 Set a user name and notes for the current and any future trace runs.
1286 This is useful for long-running and/or disconnected traces, to
1287 inform others (or yourself) as to who is running the trace, supply
1288 contact information, or otherwise explain what is going on.
1290 set trace-stop-notes
1291 show trace-stop-notes
1292 Set a note attached to the trace run, that is displayed when the
1293 trace has been stopped by a tstop command. This is useful for
1294 instance as an explanation, if you are stopping a trace run that was
1295 started by someone else.
1297 * New remote packets
1301 Dynamically enable a tracepoint in a started trace experiment.
1305 Dynamically disable a tracepoint in a started trace experiment.
1309 Set the user and notes of the trace run.
1313 Query the current status of a tracepoint.
1317 Query the minimum length of instruction at which a fast tracepoint may
1320 * Dcache size (number of lines) and line-size are now runtime-configurable
1321 via "set dcache line" and "set dcache line-size" commands.
1325 Texas Instruments TMS320C6x tic6x-*-*
1329 Renesas RL78 rl78-*-elf
1331 *** Changes in GDB 7.3.1
1333 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1335 *** Changes in GDB 7.3
1337 * GDB has a new command: "thread find [REGEXP]".
1338 It finds the thread id whose name, target id, or thread extra info
1339 matches the given regular expression.
1341 * The "catch syscall" command now works on mips*-linux* targets.
1343 * The -data-disassemble MI command now supports modes 2 and 3 for
1344 dumping the instruction opcodes.
1346 * New command line options
1348 -data-directory DIR Specify DIR as the "data-directory".
1349 This is mostly for testing purposes.
1351 * The "maint set python auto-load on|off" command has been renamed to
1352 "set auto-load-scripts on|off".
1354 * GDB has a new command: "set directories".
1355 It is like the "dir" command except that it replaces the
1356 source path list instead of augmenting it.
1358 * GDB now understands thread names.
1360 On GNU/Linux, "info threads" will display the thread name as set by
1361 prctl or pthread_setname_np.
1363 There is also a new command, "thread name", which can be used to
1364 assign a name internally for GDB to display.
1367 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1368 has been integrated into GDB.
1372 ** The function gdb.Write now accepts an optional keyword 'stream'.
1373 This keyword, when provided, will direct the output to either
1374 stdout, stderr, or GDB's logging output.
1376 ** Parameters can now be be sub-classed in Python, and in particular
1377 you may implement the get_set_doc and get_show_doc functions.
1378 This improves how Parameter set/show documentation is processed
1379 and allows for more dynamic content.
1381 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1382 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1383 have an is_valid method.
1385 ** Breakpoints can now be sub-classed in Python, and in particular
1386 you may implement a 'stop' function that is executed each time
1387 the inferior reaches that breakpoint.
1389 ** New function gdb.lookup_global_symbol looks up a global symbol.
1391 ** GDB values in Python are now callable if the value represents a
1392 function. For example, if 'some_value' represents a function that
1393 takes two integer parameters and returns a value, you can call
1394 that function like so:
1396 result = some_value (10,20)
1398 ** Module gdb.types has been added.
1399 It contains a collection of utilities for working with gdb.Types objects:
1400 get_basic_type, has_field, make_enum_dict.
1402 ** Module gdb.printing has been added.
1403 It contains utilities for writing and registering pretty-printers.
1404 New classes: PrettyPrinter, SubPrettyPrinter,
1405 RegexpCollectionPrettyPrinter.
1406 New function: register_pretty_printer.
1408 ** New commands "info pretty-printers", "enable pretty-printer" and
1409 "disable pretty-printer" have been added.
1411 ** gdb.parameter("directories") is now available.
1413 ** New function gdb.newest_frame returns the newest frame in the
1416 ** The gdb.InferiorThread class has a new "name" attribute. This
1417 holds the thread's name.
1419 ** Python Support for Inferior events.
1420 Python scripts can add observers to be notified of events
1421 occurring in the process being debugged.
1422 The following events are currently supported:
1423 - gdb.events.cont Continue event.
1424 - gdb.events.exited Inferior exited event.
1425 - gdb.events.stop Signal received, and Breakpoint hit events.
1429 ** GDB now puts template parameters in scope when debugging in an
1430 instantiation. For example, if you have:
1432 template<int X> int func (void) { return X; }
1434 then if you step into func<5>, "print X" will show "5". This
1435 feature requires proper debuginfo support from the compiler; it
1436 was added to GCC 4.5.
1438 ** The motion commands "next", "finish", "until", and "advance" now
1439 work better when exceptions are thrown. In particular, GDB will
1440 no longer lose control of the inferior; instead, the GDB will
1441 stop the inferior at the point at which the exception is caught.
1442 This functionality requires a change in the exception handling
1443 code that was introduced in GCC 4.5.
1445 * GDB now follows GCC's rules on accessing volatile objects when
1446 reading or writing target state during expression evaluation.
1447 One notable difference to prior behavior is that "print x = 0"
1448 no longer generates a read of x; the value of the assignment is
1449 now always taken directly from the value being assigned.
1451 * GDB now has some support for using labels in the program's source in
1452 linespecs. For instance, you can use "advance label" to continue
1453 execution to a label.
1455 * GDB now has support for reading and writing a new .gdb_index
1456 section. This section holds a fast index of DWARF debugging
1457 information and can be used to greatly speed up GDB startup and
1458 operation. See the documentation for `save gdb-index' for details.
1460 * The "watch" command now accepts an optional "-location" argument.
1461 When used, this causes GDB to watch the memory referred to by the
1462 expression. Such a watchpoint is never deleted due to it going out
1465 * GDB now supports thread debugging of core dumps on GNU/Linux.
1467 GDB now activates thread debugging using the libthread_db library
1468 when debugging GNU/Linux core dumps, similarly to when debugging
1469 live processes. As a result, when debugging a core dump file, GDB
1470 is now able to display pthread_t ids of threads. For example, "info
1471 threads" shows the same output as when debugging the process when it
1472 was live. In earlier releases, you'd see something like this:
1475 * 1 LWP 6780 main () at main.c:10
1477 While now you see this:
1480 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1482 It is also now possible to inspect TLS variables when debugging core
1485 When debugging a core dump generated on a machine other than the one
1486 used to run GDB, you may need to point GDB at the correct
1487 libthread_db library with the "set libthread-db-search-path"
1488 command. See the user manual for more details on this command.
1490 * When natively debugging programs on PowerPC BookE processors running
1491 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1492 which stop execution of the inferior whenever it executes an instruction
1493 at any address within the specified range. See the "PowerPC Embedded"
1494 section in the user manual for more details.
1496 * New features in the GDB remote stub, GDBserver
1498 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1499 and i686 LynxOS (version 5.x).
1501 ** GDBserver is now supported on Blackfin Linux.
1503 * New native configurations
1505 ia64 HP-UX ia64-*-hpux*
1509 Analog Devices, Inc. Blackfin Processor bfin-*
1511 * Ada task switching is now supported on sparc-elf targets when
1512 debugging a program using the Ravenscar Profile. For more information,
1513 see the "Tasking Support when using the Ravenscar Profile" section
1514 in the GDB user manual.
1516 * Guile support was removed.
1518 * New features in the GNU simulator
1520 ** The --map-info flag lists all known core mappings.
1522 ** CFI flashes may be simulated via the "cfi" device.
1524 *** Changes in GDB 7.2
1526 * Shared library support for remote targets by default
1528 When GDB is configured for a generic, non-OS specific target, like
1529 for example, --target=arm-eabi or one of the many *-*-elf targets,
1530 GDB now queries remote stubs for loaded shared libraries using the
1531 `qXfer:libraries:read' packet. Previously, shared library support
1532 was always disabled for such configurations.
1536 ** Argument Dependent Lookup (ADL)
1538 In C++ ADL lookup directs function search to the namespaces of its
1539 arguments even if the namespace has not been imported.
1549 Here the compiler will search for `foo' in the namespace of 'b'
1550 and find A::foo. GDB now supports this. This construct is commonly
1551 used in the Standard Template Library for operators.
1553 ** Improved User Defined Operator Support
1555 In addition to member operators, GDB now supports lookup of operators
1556 defined in a namespace and imported with a `using' directive, operators
1557 defined in the global scope, operators imported implicitly from an
1558 anonymous namespace, and the ADL operators mentioned in the previous
1560 GDB now also supports proper overload resolution for all the previously
1561 mentioned flavors of operators.
1563 ** static const class members
1565 Printing of static const class members that are initialized in the
1566 class definition has been fixed.
1568 * Windows Thread Information Block access.
1570 On Windows targets, GDB now supports displaying the Windows Thread
1571 Information Block (TIB) structure. This structure is visible either
1572 by using the new command `info w32 thread-information-block' or, by
1573 dereferencing the new convenience variable named `$_tlb', a
1574 thread-specific pointer to the TIB. This feature is also supported
1575 when remote debugging using GDBserver.
1577 * Static tracepoints
1579 Static tracepoints are calls in the user program into a tracing
1580 library. One such library is a port of the LTTng kernel tracer to
1581 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1582 When debugging with GDBserver, GDB now supports combining the GDB
1583 tracepoint machinery with such libraries. For example: the user can
1584 use GDB to probe a static tracepoint marker (a call from the user
1585 program into the tracing library) with the new "strace" command (see
1586 "New commands" below). This creates a "static tracepoint" in the
1587 breakpoint list, that can be manipulated with the same feature set
1588 as fast and regular tracepoints. E.g., collect registers, local and
1589 global variables, collect trace state variables, and define
1590 tracepoint conditions. In addition, the user can collect extra
1591 static tracepoint marker specific data, by collecting the new
1592 $_sdata internal variable. When analyzing the trace buffer, you can
1593 inspect $_sdata like any other variable available to GDB. For more
1594 information, see the "Tracepoints" chapter in GDB user manual. New
1595 remote packets have been defined to support static tracepoints, see
1596 the "New remote packets" section below.
1598 * Better reconstruction of tracepoints after disconnected tracing
1600 GDB will attempt to download the original source form of tracepoint
1601 definitions when starting a trace run, and then will upload these
1602 upon reconnection to the target, resulting in a more accurate
1603 reconstruction of the tracepoints that are in use on the target.
1607 You can now exercise direct control over the ways that GDB can
1608 affect your program. For instance, you can disallow the setting of
1609 breakpoints, so that the program can run continuously (assuming
1610 non-stop mode). In addition, the "observer" variable is available
1611 to switch all of the different controls; in observer mode, GDB
1612 cannot affect the target's behavior at all, which is useful for
1613 tasks like diagnosing live systems in the field.
1615 * The new convenience variable $_thread holds the number of the
1618 * New remote packets
1622 Return the address of the Windows Thread Information Block of a given thread.
1626 In response to several of the tracepoint packets, the target may now
1627 also respond with a number of intermediate `qRelocInsn' request
1628 packets before the final result packet, to have GDB handle
1629 relocating an instruction to execute at a different address. This
1630 is particularly useful for stubs that support fast tracepoints. GDB
1631 reports support for this feature in the qSupported packet.
1635 List static tracepoint markers in the target program.
1639 List static tracepoint markers at a given address in the target
1642 qXfer:statictrace:read
1644 Read the static trace data collected (by a `collect $_sdata'
1645 tracepoint action). The remote stub reports support for this packet
1646 to gdb's qSupported query.
1650 Send the current settings of GDB's permission flags.
1654 Send part of the source (textual) form of a tracepoint definition,
1655 which includes location, conditional, and action list.
1657 * The source command now accepts a -s option to force searching for the
1658 script in the source search path even if the script name specifies
1661 * New features in the GDB remote stub, GDBserver
1663 - GDBserver now support tracepoints (including fast tracepoints, and
1664 static tracepoints). The feature is currently supported by the
1665 i386-linux and amd64-linux builds. See the "Tracepoints support
1666 in gdbserver" section in the manual for more information.
1668 GDBserver JIT compiles the tracepoint's conditional agent
1669 expression bytecode into native code whenever possible for low
1670 overhead dynamic tracepoints conditionals. For such tracepoints,
1671 an expression that examines program state is evaluated when the
1672 tracepoint is reached, in order to determine whether to capture
1673 trace data. If the condition is simple and false, processing the
1674 tracepoint finishes very quickly and no data is gathered.
1676 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1677 for static tracepoints support.
1679 - GDBserver now supports x86_64 Windows 64-bit debugging.
1681 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1682 it understands register description.
1684 * The --batch flag now disables pagination and queries.
1686 * X86 general purpose registers
1688 GDB now supports reading/writing byte, word and double-word x86
1689 general purpose registers directly. This means you can use, say,
1690 $ah or $ax to refer, respectively, to the byte register AH and
1691 16-bit word register AX that are actually portions of the 32-bit
1692 register EAX or 64-bit register RAX.
1694 * The `commands' command now accepts a range of breakpoints to modify.
1695 A plain `commands' following a command that creates multiple
1696 breakpoints affects all the breakpoints set by that command. This
1697 applies to breakpoints set by `rbreak', and also applies when a
1698 single `break' command creates multiple breakpoints (e.g.,
1699 breakpoints on overloaded c++ functions).
1701 * The `rbreak' command now accepts a filename specification as part of
1702 its argument, limiting the functions selected by the regex to those
1703 in the specified file.
1705 * Support for remote debugging Windows and SymbianOS shared libraries
1706 from Unix hosts has been improved. Non Windows GDB builds now can
1707 understand target reported file names that follow MS-DOS based file
1708 system semantics, such as file names that include drive letters and
1709 use the backslash character as directory separator. This makes it
1710 possible to transparently use the "set sysroot" and "set
1711 solib-search-path" on Unix hosts to point as host copies of the
1712 target's shared libraries. See the new command "set
1713 target-file-system-kind" described below, and the "Commands to
1714 specify files" section in the user manual for more information.
1718 eval template, expressions...
1719 Convert the values of one or more expressions under the control
1720 of the string template to a command line, and call it.
1722 set target-file-system-kind unix|dos-based|auto
1723 show target-file-system-kind
1724 Set or show the assumed file system kind for target reported file
1727 save breakpoints <filename>
1728 Save all current breakpoint definitions to a file suitable for use
1729 in a later debugging session. To read the saved breakpoint
1730 definitions, use the `source' command.
1732 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1735 info static-tracepoint-markers
1736 Display information about static tracepoint markers in the target.
1738 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1739 Define a static tracepoint by probing a marker at the given
1740 function, line, address, or marker ID.
1744 Enable and disable observer mode.
1746 set may-write-registers on|off
1747 set may-write-memory on|off
1748 set may-insert-breakpoints on|off
1749 set may-insert-tracepoints on|off
1750 set may-insert-fast-tracepoints on|off
1751 set may-interrupt on|off
1752 Set individual permissions for GDB effects on the target. Note that
1753 some of these settings can have undesirable or surprising
1754 consequences, particularly when changed in the middle of a session.
1755 For instance, disabling the writing of memory can prevent
1756 breakpoints from being inserted, cause single-stepping to fail, or
1757 even crash your program, if you disable after breakpoints have been
1758 inserted. However, GDB should not crash.
1760 set record memory-query on|off
1761 show record memory-query
1762 Control whether to stop the inferior if memory changes caused
1763 by an instruction cannot be recorded.
1768 The disassemble command now supports "start,+length" form of two arguments.
1772 ** GDB now provides a new directory location, called the python directory,
1773 where Python scripts written for GDB can be installed. The location
1774 of that directory is <data-directory>/python, where <data-directory>
1775 is the GDB data directory. For more details, see section `Scripting
1776 GDB using Python' in the manual.
1778 ** The GDB Python API now has access to breakpoints, symbols, symbol
1779 tables, program spaces, inferiors, threads and frame's code blocks.
1780 Additionally, GDB Parameters can now be created from the API, and
1781 manipulated via set/show in the CLI.
1783 ** New functions gdb.target_charset, gdb.target_wide_charset,
1784 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1786 ** New exception gdb.GdbError.
1788 ** Pretty-printers are now also looked up in the current program space.
1790 ** Pretty-printers can now be individually enabled and disabled.
1792 ** GDB now looks for names of Python scripts to auto-load in a
1793 special section named `.debug_gdb_scripts', in addition to looking
1794 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1796 * Tracepoint actions were unified with breakpoint commands. In particular,
1797 there are no longer differences in "info break" output for breakpoints and
1798 tracepoints and the "commands" command can be used for both tracepoints and
1799 regular breakpoints.
1803 ARM Symbian arm*-*-symbianelf*
1805 * D language support.
1806 GDB now supports debugging programs written in the D programming
1809 * GDB now supports the extended ptrace interface for PowerPC which is
1810 available since Linux kernel version 2.6.34. This automatically enables
1811 any hardware breakpoints and additional hardware watchpoints available in
1812 the processor. The old ptrace interface exposes just one hardware
1813 watchpoint and no hardware breakpoints.
1815 * GDB is now able to use the Data Value Compare (DVC) register available on
1816 embedded PowerPC processors to implement in hardware simple watchpoint
1817 conditions of the form:
1819 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1821 This works in native GDB running on Linux kernels with the extended ptrace
1822 interface mentioned above.
1824 *** Changes in GDB 7.1
1828 ** Namespace Support
1830 GDB now supports importing of namespaces in C++. This enables the
1831 user to inspect variables from imported namespaces. Support for
1832 namepace aliasing has also been added. So, if a namespace is
1833 aliased in the current scope (e.g. namepace C=A; ) the user can
1834 print variables using the alias (e.g. (gdb) print C::x).
1838 All known bugs relating to the printing of virtual base class were
1839 fixed. It is now possible to call overloaded static methods using a
1844 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1845 and reinterpret_cast<> are now handled by the C++ expression parser.
1849 Xilinx MicroBlaze microblaze-*-*
1854 Xilinx MicroBlaze microblaze
1857 * Multi-program debugging.
1859 GDB now has support for multi-program (a.k.a. multi-executable or
1860 multi-exec) debugging. This allows for debugging multiple inferiors
1861 simultaneously each running a different program under the same GDB
1862 session. See "Debugging Multiple Inferiors and Programs" in the
1863 manual for more information. This implied some user visible changes
1864 in the multi-inferior support. For example, "info inferiors" now
1865 lists inferiors that are not running yet or that have exited
1866 already. See also "New commands" and "New options" below.
1868 * New tracing features
1870 GDB's tracepoint facility now includes several new features:
1872 ** Trace state variables
1874 GDB tracepoints now include support for trace state variables, which
1875 are variables managed by the target agent during a tracing
1876 experiment. They are useful for tracepoints that trigger each
1877 other, so for instance one tracepoint can count hits in a variable,
1878 and then a second tracepoint has a condition that is true when the
1879 count reaches a particular value. Trace state variables share the
1880 $-syntax of GDB convenience variables, and can appear in both
1881 tracepoint actions and condition expressions. Use the "tvariable"
1882 command to create, and "info tvariables" to view; see "Trace State
1883 Variables" in the manual for more detail.
1887 GDB now includes an option for defining fast tracepoints, which
1888 targets may implement more efficiently, such as by installing a jump
1889 into the target agent rather than a trap instruction. The resulting
1890 speedup can be by two orders of magnitude or more, although the
1891 tradeoff is that some program locations on some target architectures
1892 might not allow fast tracepoint installation, for instance if the
1893 instruction to be replaced is shorter than the jump. To request a
1894 fast tracepoint, use the "ftrace" command, with syntax identical to
1895 the regular trace command.
1897 ** Disconnected tracing
1899 It is now possible to detach GDB from the target while it is running
1900 a trace experiment, then reconnect later to see how the experiment
1901 is going. In addition, a new variable disconnected-tracing lets you
1902 tell the target agent whether to continue running a trace if the
1903 connection is lost unexpectedly.
1907 GDB now has the ability to save the trace buffer into a file, and
1908 then use that file as a target, similarly to you can do with
1909 corefiles. You can select trace frames, print data that was
1910 collected in them, and use tstatus to display the state of the
1911 tracing run at the moment that it was saved. To create a trace
1912 file, use "tsave <filename>", and to use it, do "target tfile
1915 ** Circular trace buffer
1917 You can ask the target agent to handle the trace buffer as a
1918 circular buffer, discarding the oldest trace frames to make room for
1919 newer ones, by setting circular-trace-buffer to on. This feature may
1920 not be available for all target agents.
1925 The disassemble command, when invoked with two arguments, now requires
1926 the arguments to be comma-separated.
1929 The info variables command now displays variable definitions. Files
1930 which only declare a variable are not shown.
1933 The source command is now capable of sourcing Python scripts.
1934 This feature is dependent on the debugger being build with Python
1937 Related to this enhancement is also the introduction of a new command
1938 "set script-extension" (see below).
1940 * New commands (for set/show, see "New options" below)
1942 record save [<FILENAME>]
1943 Save a file (in core file format) containing the process record
1944 execution log for replay debugging at a later time.
1946 record restore <FILENAME>
1947 Restore the process record execution log that was saved at an
1948 earlier time, for replay debugging.
1950 add-inferior [-copies <N>] [-exec <FILENAME>]
1953 clone-inferior [-copies <N>] [ID]
1954 Make a new inferior ready to execute the same program another
1955 inferior has loaded.
1960 maint info program-spaces
1961 List the program spaces loaded into GDB.
1963 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1964 show remote interrupt-sequence
1965 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1966 as the sequence to the remote target in order to interrupt the execution.
1967 Ctrl-C is a default. Some system prefers BREAK which is high level of
1968 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1969 Magic SysRq g. It is BREAK signal and character 'g'.
1971 set remote interrupt-on-connect [on | off]
1972 show remote interrupt-on-connect
1973 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1974 remote target when gdb connects to it. This is needed when you debug
1977 set remotebreak [on | off]
1979 Deprecated. Use "set/show remote interrupt-sequence" instead.
1981 tvariable $NAME [ = EXP ]
1982 Create or modify a trace state variable.
1985 List trace state variables and their values.
1987 delete tvariable $NAME ...
1988 Delete one or more trace state variables.
1991 Evaluate the given expressions without collecting anything into the
1992 trace buffer. (Valid in tracepoint actions only.)
1994 ftrace FN / FILE:LINE / *ADDR
1995 Define a fast tracepoint at the given function, line, or address.
1997 * New expression syntax
1999 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2000 GDB now parses 0b101010 identically with 42.
2004 set follow-exec-mode new|same
2005 show follow-exec-mode
2006 Control whether GDB reuses the same inferior across an exec call or
2007 creates a new one. This is useful to be able to restart the old
2008 executable after the inferior having done an exec call.
2010 set default-collect EXPR, ...
2011 show default-collect
2012 Define a list of expressions to be collected at each tracepoint.
2013 This is a useful way to ensure essential items are not overlooked,
2014 such as registers or a critical global variable.
2016 set disconnected-tracing
2017 show disconnected-tracing
2018 If set to 1, the target is instructed to continue tracing if it
2019 loses its connection to GDB. If 0, the target is to stop tracing
2022 set circular-trace-buffer
2023 show circular-trace-buffer
2024 If set to on, the target is instructed to use a circular trace buffer
2025 and discard the oldest trace frames instead of stopping the trace due
2026 to a full trace buffer. If set to off, the trace stops when the buffer
2027 fills up. Some targets may not support this.
2029 set script-extension off|soft|strict
2030 show script-extension
2031 If set to "off", the debugger does not perform any script language
2032 recognition, and all sourced files are assumed to be GDB scripts.
2033 If set to "soft" (the default), files are sourced according to
2034 filename extension, falling back to GDB scripts if the first
2036 If set to "strict", files are sourced according to filename extension.
2038 set ada trust-PAD-over-XVS on|off
2039 show ada trust-PAD-over-XVS
2040 If off, activate a workaround against a bug in the debugging information
2041 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2042 the GCC sources for more information about the GNAT encoding and
2043 PAD types in particular). It is always safe to set this option to
2044 off, but this introduces a slight performance penalty. The default
2047 * Python API Improvements
2049 ** GDB provides the new class gdb.LazyString. This is useful in
2050 some pretty-printing cases. The new method gdb.Value.lazy_string
2051 provides a simple way to create objects of this type.
2053 ** The fields returned by gdb.Type.fields now have an
2054 `is_base_class' attribute.
2056 ** The new method gdb.Type.range returns the range of an array type.
2058 ** The new method gdb.parse_and_eval can be used to parse and
2059 evaluate an expression.
2061 * New remote packets
2064 Define a trace state variable.
2067 Get the current value of a trace state variable.
2070 Set desired tracing behavior upon disconnection.
2073 Set the trace buffer to be linear or circular.
2076 Get data about the tracepoints currently in use.
2080 Process record now works correctly with hardware watchpoints.
2082 Multiple bug fixes have been made to the mips-irix port, making it
2083 much more reliable. In particular:
2084 - Debugging threaded applications is now possible again. Previously,
2085 GDB would hang while starting the program, or while waiting for
2086 the program to stop at a breakpoint.
2087 - Attaching to a running process no longer hangs.
2088 - An error occurring while loading a core file has been fixed.
2089 - Changing the value of the PC register now works again. This fixes
2090 problems observed when using the "jump" command, or when calling
2091 a function from GDB, or even when assigning a new value to $pc.
2092 - With the "finish" and "return" commands, the return value for functions
2093 returning a small array is now correctly printed.
2094 - It is now possible to break on shared library code which gets executed
2095 during a shared library init phase (code executed while executing
2096 their .init section). Previously, the breakpoint would have no effect.
2097 - GDB is now able to backtrace through the signal handler for
2098 non-threaded programs.
2100 PIE (Position Independent Executable) programs debugging is now supported.
2101 This includes debugging execution of PIC (Position Independent Code) shared
2102 libraries although for that, it should be possible to run such libraries as an
2105 *** Changes in GDB 7.0
2107 * GDB now has an interface for JIT compilation. Applications that
2108 dynamically generate code can create symbol files in memory and register
2109 them with GDB. For users, the feature should work transparently, and
2110 for JIT developers, the interface is documented in the GDB manual in the
2111 "JIT Compilation Interface" chapter.
2113 * Tracepoints may now be conditional. The syntax is as for
2114 breakpoints; either an "if" clause appended to the "trace" command,
2115 or the "condition" command is available. GDB sends the condition to
2116 the target for evaluation using the same bytecode format as is used
2117 for tracepoint actions.
2119 * The disassemble command now supports: an optional /r modifier, print the
2120 raw instructions in hex as well as in symbolic form, and an optional /m
2121 modifier to print mixed source+assembly.
2123 * Process record and replay
2125 In a architecture environment that supports ``process record and
2126 replay'', ``process record and replay'' target can record a log of
2127 the process execution, and replay it with both forward and reverse
2130 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2131 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2132 set execution-direction {forward|reverse}, for targets that support
2135 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2136 feature is available with a native GDB running on kernel version
2139 * GDB now has support for multi-byte and wide character sets on the
2140 target. Strings whose character type is wchar_t, char16_t, or
2141 char32_t are now correctly printed. GDB supports wide- and unicode-
2142 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2143 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2144 `printf'. This feature requires iconv to work properly; if your
2145 system does not have a working iconv, GDB can use GNU libiconv. See
2146 the installation instructions for more information.
2148 * GDB now supports automatic retrieval of shared library files from
2149 remote targets. To use this feature, specify a system root that begins
2150 with the `remote:' prefix, either via the `set sysroot' command or via
2151 the `--with-sysroot' configure-time option.
2153 * "info sharedlibrary" now takes an optional regex of libraries to show,
2154 and it now reports if a shared library has no debugging information.
2156 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2157 now complete on file names.
2159 * When completing in expressions, gdb will attempt to limit
2160 completions to allowable structure or union fields, where appropriate.
2161 For instance, consider:
2163 # struct example { int f1; double f2; };
2164 # struct example variable;
2167 If the user types TAB at the end of this command line, the available
2168 completions will be "f1" and "f2".
2170 * Inlined functions are now supported. They show up in backtraces, and
2171 the "step", "next", and "finish" commands handle them automatically.
2173 * GDB now supports the token-splicing (##) and stringification (#)
2174 operators when expanding macros. It also supports variable-arity
2177 * GDB now supports inspecting extra signal information, exported by
2178 the new $_siginfo convenience variable. The feature is currently
2179 implemented on linux ARM, i386 and amd64.
2181 * GDB can now display the VFP floating point registers and NEON vector
2182 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2183 can provide these registers (requires Linux 2.6.30 or later). Remote
2184 and simulator targets may also provide them.
2186 * New remote packets
2189 Search memory for a sequence of bytes.
2192 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2193 operation over reliable transport links. Use of this packet is
2194 controlled by the `set remote noack-packet' command.
2197 Kill the process with the specified process ID. Use this in preference
2198 to `k' when multiprocess protocol extensions are supported.
2201 Obtains additional operating system information
2205 Read or write additional signal information.
2207 * Removed remote protocol undocumented extension
2209 An undocumented extension to the remote protocol's `S' stop reply
2210 packet that permited the stub to pass a process id was removed.
2211 Remote servers should use the `T' stop reply packet instead.
2213 * GDB now supports multiple function calling conventions according to the
2214 DWARF-2 DW_AT_calling_convention function attribute.
2216 * The SH target utilizes the aforementioned change to distinguish between gcc
2217 and Renesas calling convention. It also adds the new CLI commands
2218 `set/show sh calling-convention'.
2220 * GDB can now read compressed debug sections, as produced by GNU gold
2221 with the --compress-debug-sections=zlib flag.
2223 * 64-bit core files are now supported on AIX.
2225 * Thread switching is now supported on Tru64.
2227 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2228 which will be allocated using malloc later in program execution.
2230 * The qXfer:libraries:read remote procotol packet now allows passing a
2231 list of section offsets.
2233 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2234 conditions handling signals delivered during attach or thread creation
2235 have also been fixed.
2237 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2238 From the user's standpoint, all unqualified instances of True and False
2239 are treated as the standard definitions, regardless of context.
2241 * GDB now parses C++ symbol and type names more flexibly. For
2244 template<typename T> class C { };
2247 GDB will now correctly handle all of:
2249 ptype C<char const *>
2250 ptype C<char const*>
2251 ptype C<const char *>
2252 ptype C<const char*>
2254 * New features in the GDB remote stub, gdbserver
2256 - The "--wrapper" command-line argument tells gdbserver to use a
2257 wrapper program to launch programs for debugging.
2259 - On PowerPC and S/390 targets, it is now possible to use a single
2260 gdbserver executable to debug both 32-bit and 64-bit programs.
2261 (This requires gdbserver itself to be built as a 64-bit executable.)
2263 - gdbserver uses the new noack protocol mode for TCP connections to
2264 reduce communications latency, if also supported and enabled in GDB.
2266 - Support for the sparc64-linux-gnu target is now included in
2269 - The amd64-linux build of gdbserver now supports debugging both
2270 32-bit and 64-bit programs.
2272 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2273 now support hardware watchpoints, and will use them automatically
2278 GDB now has support for scripting using Python. Whether this is
2279 available is determined at configure time.
2281 New GDB commands can now be written in Python.
2283 * Ada tasking support
2285 Ada tasks can now be inspected in GDB. The following commands have
2289 Print the list of Ada tasks.
2291 Print detailed information about task number N.
2293 Print the task number of the current task.
2295 Switch the context of debugging to task number N.
2297 * Support for user-defined prefixed commands. The "define" command can
2298 add new commands to existing prefixes, e.g. "target".
2300 * Multi-inferior, multi-process debugging.
2302 GDB now has generalized support for multi-inferior debugging. See
2303 "Debugging Multiple Inferiors" in the manual for more information.
2304 Although availability still depends on target support, the command
2305 set is more uniform now. The GNU/Linux specific multi-forks support
2306 has been migrated to this new framework. This implied some user
2307 visible changes; see "New commands" and also "Removed commands"
2310 * Target descriptions can now describe the target OS ABI. See the
2311 "Target Description Format" section in the user manual for more
2314 * Target descriptions can now describe "compatible" architectures
2315 to indicate that the target can execute applications for a different
2316 architecture in addition to those for the main target architecture.
2317 See the "Target Description Format" section in the user manual for
2320 * Multi-architecture debugging.
2322 GDB now includes general supports for debugging applications on
2323 hybrid systems that use more than one single processor architecture
2324 at the same time. Each such hybrid architecture still requires
2325 specific support to be added. The only hybrid architecture supported
2326 in this version of GDB is the Cell Broadband Engine.
2328 * GDB now supports integrated debugging of Cell/B.E. applications that
2329 use both the PPU and SPU architectures. To enable support for hybrid
2330 Cell/B.E. debugging, you need to configure GDB to support both the
2331 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2332 --enable-targets configure option.
2334 * Non-stop mode debugging.
2336 For some targets, GDB now supports an optional mode of operation in
2337 which you can examine stopped threads while other threads continue
2338 to execute freely. This is referred to as non-stop mode, with the
2339 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2340 section in the user manual for more information.
2342 To be able to support remote non-stop debugging, a remote stub needs
2343 to implement the non-stop mode remote protocol extensions, as
2344 described in the "Remote Non-Stop" section of the user manual. The
2345 GDB remote stub, gdbserver, has been adjusted to support these
2346 extensions on linux targets.
2348 * New commands (for set/show, see "New options" below)
2350 catch syscall [NAME(S) | NUMBER(S)]
2351 Catch system calls. Arguments, which should be names of system
2352 calls or their numbers, mean catch only those syscalls. Without
2353 arguments, every syscall will be caught. When the inferior issues
2354 any of the specified syscalls, GDB will stop and announce the system
2355 call, both when it is called and when its call returns. This
2356 feature is currently available with a native GDB running on the
2357 Linux Kernel, under the following architectures: x86, x86_64,
2358 PowerPC and PowerPC64.
2360 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2362 Search memory for a sequence of bytes.
2364 maint set python print-stack
2365 maint show python print-stack
2366 Show a stack trace when an error is encountered in a Python script.
2369 Invoke CODE by passing it to the Python interpreter.
2374 These allow macros to be defined, undefined, and listed
2378 Show operating system information about processes.
2381 List the inferiors currently under GDB's control.
2384 Switch focus to inferior number NUM.
2387 Detach from inferior number NUM.
2390 Kill inferior number NUM.
2394 set spu stop-on-load
2395 show spu stop-on-load
2396 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2398 set spu auto-flush-cache
2399 show spu auto-flush-cache
2400 Control whether to automatically flush the software-managed cache
2401 during Cell/B.E. debugging.
2403 set sh calling-convention
2404 show sh calling-convention
2405 Control the calling convention used when calling SH target functions.
2408 show debug timestamp
2409 Control display of timestamps with GDB debugging output.
2411 set disassemble-next-line
2412 show disassemble-next-line
2413 Control display of disassembled source lines or instructions when
2416 set remote noack-packet
2417 show remote noack-packet
2418 Set/show the use of remote protocol QStartNoAckMode packet. See above
2419 under "New remote packets."
2421 set remote query-attached-packet
2422 show remote query-attached-packet
2423 Control use of remote protocol `qAttached' (query-attached) packet.
2425 set remote read-siginfo-object
2426 show remote read-siginfo-object
2427 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2430 set remote write-siginfo-object
2431 show remote write-siginfo-object
2432 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2435 set remote reverse-continue
2436 show remote reverse-continue
2437 Control use of remote protocol 'bc' (reverse-continue) packet.
2439 set remote reverse-step
2440 show remote reverse-step
2441 Control use of remote protocol 'bs' (reverse-step) packet.
2443 set displaced-stepping
2444 show displaced-stepping
2445 Control displaced stepping mode. Displaced stepping is a way to
2446 single-step over breakpoints without removing them from the debuggee.
2447 Also known as "out-of-line single-stepping".
2450 show debug displaced
2451 Control display of debugging info for displaced stepping.
2453 maint set internal-error
2454 maint show internal-error
2455 Control what GDB does when an internal error is detected.
2457 maint set internal-warning
2458 maint show internal-warning
2459 Control what GDB does when an internal warning is detected.
2464 Use a wrapper program to launch programs for debugging.
2466 set multiple-symbols (all|ask|cancel)
2467 show multiple-symbols
2468 The value of this variable can be changed to adjust the debugger behavior
2469 when an expression or a breakpoint location contains an ambiguous symbol
2470 name (an overloaded function name, for instance).
2472 set breakpoint always-inserted
2473 show breakpoint always-inserted
2474 Keep breakpoints always inserted in the target, as opposed to inserting
2475 them when resuming the target, and removing them when the target stops.
2476 This option can improve debugger performance on slow remote targets.
2478 set arm fallback-mode (arm|thumb|auto)
2479 show arm fallback-mode
2480 set arm force-mode (arm|thumb|auto)
2482 These commands control how ARM GDB determines whether instructions
2483 are ARM or Thumb. The default for both settings is auto, which uses
2484 the current CPSR value for instructions without symbols; previous
2485 versions of GDB behaved as if "set arm fallback-mode arm".
2487 set disable-randomization
2488 show disable-randomization
2489 Standalone programs run with the virtual address space randomization enabled
2490 by default on some platforms. This option keeps the addresses stable across
2491 multiple debugging sessions.
2495 Control whether other threads are stopped or not when some thread hits
2500 Requests that asynchronous execution is enabled in the target, if available.
2501 In this case, it's possible to resume target in the background, and interact
2502 with GDB while the target is running. "show target-async" displays the
2503 current state of asynchronous execution of the target.
2505 set target-wide-charset
2506 show target-wide-charset
2507 The target-wide-charset is the name of the character set that GDB
2508 uses when printing characters whose type is wchar_t.
2510 set tcp auto-retry (on|off)
2512 set tcp connect-timeout
2513 show tcp connect-timeout
2514 These commands allow GDB to retry failed TCP connections to a remote stub
2515 with a specified timeout period; this is useful if the stub is launched
2516 in parallel with GDB but may not be ready to accept connections immediately.
2518 set libthread-db-search-path
2519 show libthread-db-search-path
2520 Control list of directories which GDB will search for appropriate
2523 set schedule-multiple (on|off)
2524 show schedule-multiple
2525 Allow GDB to resume all threads of all processes or only threads of
2526 the current process.
2530 Use more aggressive caching for accesses to the stack. This improves
2531 performance of remote debugging (particularly backtraces) without
2532 affecting correctness.
2534 set interactive-mode (on|off|auto)
2535 show interactive-mode
2536 Control whether GDB runs in interactive mode (on) or not (off).
2537 When in interactive mode, GDB waits for the user to answer all
2538 queries. Otherwise, GDB does not wait and assumes the default
2539 answer. When set to auto (the default), GDB determines which
2540 mode to use based on the stdin settings.
2545 For program forks, this is replaced by the new more generic `info
2546 inferiors' command. To list checkpoints, you can still use the
2547 `info checkpoints' command, which was an alias for the `info forks'
2551 Replaced by the new `inferior' command. To switch between
2552 checkpoints, you can still use the `restart' command, which was an
2553 alias for the `fork' command.
2556 This is removed, since some targets don't have a notion of
2557 processes. To switch between processes, you can still use the
2558 `inferior' command using GDB's own inferior number.
2561 For program forks, this is replaced by the new more generic `kill
2562 inferior' command. To delete a checkpoint, you can still use the
2563 `delete checkpoint' command, which was an alias for the `delete
2567 For program forks, this is replaced by the new more generic `detach
2568 inferior' command. To detach a checkpoint, you can still use the
2569 `detach checkpoint' command, which was an alias for the `detach
2572 * New native configurations
2574 x86/x86_64 Darwin i[34567]86-*-darwin*
2576 x86_64 MinGW x86_64-*-mingw*
2580 Lattice Mico32 lm32-*
2581 x86 DICOS i[34567]86-*-dicos*
2582 x86_64 DICOS x86_64-*-dicos*
2585 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2586 (mingw32ce) debugging.
2592 These commands were actually not implemented on any target.
2594 *** Changes in GDB 6.8
2596 * New native configurations
2598 NetBSD/hppa hppa*-*netbsd*
2599 Xtensa GNU/Linux xtensa*-*-linux*
2603 NetBSD/hppa hppa*-*-netbsd*
2604 Xtensa GNU/Lunux xtensa*-*-linux*
2606 * Change in command line behavior -- corefiles vs. process ids.
2608 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2609 attaching to process NUMBER fails, GDB no longer attempts to open a
2610 core file named NUMBER. Attaching to a program using the -c option
2611 is no longer supported. Instead, use the '-p' or '--pid' options.
2613 * GDB can now be built as a native debugger for debugging Windows x86
2614 (mingw32) Portable Executable (PE) programs.
2616 * Pending breakpoints no longer change their number when their address
2619 * GDB now supports breakpoints with multiple locations,
2620 including breakpoints on C++ constructors, inside C++ templates,
2621 and in inlined functions.
2623 * GDB's ability to debug optimized code has been improved. GDB more
2624 accurately identifies function bodies and lexical blocks that occupy
2625 more than one contiguous range of addresses.
2627 * Target descriptions can now describe registers for PowerPC.
2629 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2630 registers on PowerPC targets.
2632 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2633 targets even when the libthread_db library is not available.
2635 * The GDB remote stub, gdbserver, now supports the new file transfer
2636 commands (remote put, remote get, and remote delete).
2638 * The GDB remote stub, gdbserver, now supports run and attach in
2639 extended-remote mode.
2641 * hppa*64*-*-hpux11* target broken
2642 The debugger is unable to start a program and fails with the following
2643 error: "Error trying to get information about dynamic linker".
2644 The gdb-6.7 release is also affected.
2646 * GDB now supports the --enable-targets= configure option to allow
2647 building a single GDB executable that supports multiple remote
2648 target architectures.
2650 * GDB now supports debugging C and C++ programs which use the
2651 Decimal Floating Point extension. In addition, the PowerPC target
2652 now has a set of pseudo-registers to inspect decimal float values
2653 stored in two consecutive float registers.
2655 * The -break-insert MI command can optionally create pending
2658 * Improved support for debugging Ada
2659 Many improvements to the Ada language support have been made. These
2661 - Better support for Ada2005 interface types
2662 - Improved handling of arrays and slices in general
2663 - Better support for Taft-amendment types
2664 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2666 - Improved command completion in Ada
2669 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2674 set print frame-arguments (all|scalars|none)
2675 show print frame-arguments
2676 The value of this variable can be changed to control which argument
2677 values should be printed by the debugger when displaying a frame.
2682 Transfer files to and from a remote target, and delete remote files.
2689 Transfer files to and from a remote target, and delete remote files.
2691 * New remote packets
2698 Open, close, read, write, and delete files on the remote system.
2701 Attach to an existing process on the remote system, in extended-remote
2705 Run a new process on the remote system, in extended-remote mode.
2707 *** Changes in GDB 6.7
2709 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2710 bfd, libiberty and opcodes, as revealed by static analysis donated by
2711 Coverity, Inc. (http://scan.coverity.com).
2713 * When looking up multiply-defined global symbols, GDB will now prefer the
2714 symbol definition in the current shared library if it was built using the
2715 -Bsymbolic linker option.
2717 * When the Text User Interface (TUI) is not configured, GDB will now
2718 recognize the -tui command-line option and print a message that the TUI
2721 * The GDB remote stub, gdbserver, now has lower overhead for high
2722 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2724 * GDB for MIPS targets now autodetects whether a remote target provides
2725 32-bit or 64-bit register values.
2727 * Support for C++ member pointers has been improved.
2729 * GDB now understands XML target descriptions, which specify the
2730 target's overall architecture. GDB can read a description from
2731 a local file or over the remote serial protocol.
2733 * Vectors of single-byte data use a new integer type which is not
2734 automatically displayed as character or string data.
2736 * The /s format now works with the print command. It displays
2737 arrays of single-byte integers and pointers to single-byte integers
2740 * Target descriptions can now describe target-specific registers,
2741 for architectures which have implemented the support (currently
2742 only ARM, M68K, and MIPS).
2744 * GDB and the GDB remote stub, gdbserver, now support the XScale
2747 * The GDB remote stub, gdbserver, has been updated to support
2748 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2749 has been rewritten to use the standard GDB remote protocol.
2751 * GDB can now step into C++ functions which are called through thunks.
2753 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2755 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2756 layout. It also supports a TextSeg= and DataSeg= response when only
2757 segment base addresses (rather than offsets) are available.
2759 * The /i format now outputs any trailing branch delay slot instructions
2760 immediately following the last instruction within the count specified.
2762 * The GDB remote protocol "T" stop reply packet now supports a
2763 "library" response. Combined with the new "qXfer:libraries:read"
2764 packet, this response allows GDB to debug shared libraries on targets
2765 where the operating system manages the list of loaded libraries (e.g.
2766 Windows and SymbianOS).
2768 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2769 (DLLs) on Windows and Windows CE targets.
2771 * GDB now supports a faster verification that a .debug file matches its binary
2772 according to its build-id signature, if the signature is present.
2778 Enable or disable hardware flow control (RTS/CTS) on the serial port
2779 when debugging using remote targets.
2781 set mem inaccessible-by-default
2782 show mem inaccessible-by-default
2783 If the target supplies a memory map, for instance via the remote
2784 protocol's "qXfer:memory-map:read" packet, setting this variable
2785 prevents GDB from accessing memory outside the memory map. This
2786 is useful for targets with memory mapped registers or which react
2787 badly to accesses of unmapped address space.
2789 set breakpoint auto-hw
2790 show breakpoint auto-hw
2791 If the target supplies a memory map, for instance via the remote
2792 protocol's "qXfer:memory-map:read" packet, setting this variable
2793 lets GDB use hardware breakpoints automatically for memory regions
2794 where it can not use software breakpoints. This covers both the
2795 "break" command and internal breakpoints used for other commands
2796 including "next" and "finish".
2799 catch exception unhandled
2800 Stop the program execution when Ada exceptions are raised.
2803 Stop the program execution when an Ada assertion failed.
2807 Set an alternate system root for target files. This is a more
2808 general version of "set solib-absolute-prefix", which is now
2809 an alias to "set sysroot".
2812 Provide extended SPU facility status information. This set of
2813 commands is available only when debugging the Cell/B.E. SPU
2816 * New native configurations
2818 OpenBSD/sh sh*-*openbsd*
2821 unset tdesc filename
2823 Use the specified local file as an XML target description, and do
2824 not query the target for its built-in description.
2828 OpenBSD/sh sh*-*-openbsd*
2829 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2830 Toshiba Media Processor mep-elf
2832 * New remote packets
2835 Ignore the specified signals; pass them directly to the debugged program
2836 without stopping other threads or reporting them to GDB.
2838 qXfer:features:read:
2839 Read an XML target description from the target, which describes its
2844 Read or write contents of an spufs file on the target system. These
2845 packets are available only on the Cell/B.E. SPU architecture.
2847 qXfer:libraries:read:
2848 Report the loaded shared libraries. Combined with new "T" packet
2849 response, this packet allows GDB to debug shared libraries on
2850 targets where the operating system manages the list of loaded
2851 libraries (e.g. Windows and SymbianOS).
2855 Support for these obsolete configurations has been removed.
2863 i[34567]86-*-lynxos*
2864 i[34567]86-*-netware*
2865 i[34567]86-*-sco3.2v5*
2866 i[34567]86-*-sco3.2v4*
2868 i[34567]86-*-sysv4.2*
2871 i[34567]86-*-unixware2*
2872 i[34567]86-*-unixware*
2881 * Other removed features
2888 Various m68k-only ROM monitors.
2895 Various Renesas ROM monitors and debugging interfaces for SH and
2900 Support for a Macraigor serial interface to on-chip debugging.
2901 GDB does not directly support the newer parallel or USB
2906 A debug information format. The predecessor to DWARF 2 and
2907 DWARF 3, which are still supported.
2909 Support for the HP aCC compiler on HP-UX/PA-RISC
2911 SOM-encapsulated symbolic debugging information, automatic
2912 invocation of pxdb, and the aCC custom C++ ABI. This does not
2913 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2914 with aCC can still be debugged on an assembly level.
2916 MIPS ".pdr" sections
2918 A MIPS-specific format used to describe stack frame layout
2919 in debugging information.
2923 GDB could work with an older version of Guile to debug
2924 the interpreter and Scheme programs running in it.
2926 set mips stack-arg-size
2927 set mips saved-gpreg-size
2929 Use "set mips abi" to control parameter passing for MIPS.
2931 *** Changes in GDB 6.6
2936 Cell Broadband Engine SPU spu-elf
2938 * GDB can now be configured as a cross-debugger targeting native Windows
2939 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2940 running on a Windows system over TCP/IP to debug Windows programs.
2942 * The GDB remote stub, gdbserver, has been updated to support Windows and
2943 Cygwin debugging. Both single-threaded and multi-threaded programs are
2946 * The "set trust-readonly-sections" command works again. This command was
2947 broken in GDB 6.3, 6.4, and 6.5.
2949 * The "load" command now supports writing to flash memory, if the remote
2950 stub provides the required support.
2952 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2953 longer requires symbolic debug information (e.g. DWARF-2).
2958 unset substitute-path
2959 show substitute-path
2960 Manage a list of substitution rules that GDB uses to rewrite the name
2961 of the directories where the sources are located. This can be useful
2962 for instance when the sources were moved to a different location
2963 between compilation and debugging.
2967 Print each CLI command as it is executed. Each command is prefixed with
2968 a number of `+' symbols representing the nesting depth.
2969 The source command now has a `-v' option to enable the same feature.
2973 The ARM Demon monitor support (RDP protocol, "target rdp").
2975 Kernel Object Display, an embedded debugging feature which only worked with
2976 an obsolete version of Cisco IOS.
2978 The 'set download-write-size' and 'show download-write-size' commands.
2980 * New remote packets
2983 Tell a stub about GDB client features, and request remote target features.
2984 The first feature implemented is PacketSize, which allows the target to
2985 specify the size of packets it can handle - to minimize the number of
2986 packets required and improve performance when connected to a remote
2990 Fetch an OS auxilliary vector from the remote stub. This packet is a
2991 more efficient replacement for qPart:auxv:read.
2993 qXfer:memory-map:read:
2994 Fetch a memory map from the remote stub, including information about
2995 RAM, ROM, and flash memory devices.
3000 Erase and program a flash memory device.
3002 * Removed remote packets
3005 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3006 used it, and only gdbserver implemented it.
3008 *** Changes in GDB 6.5
3012 Renesas M32C/M16C m32c-elf
3014 Morpho Technologies ms1 ms1-elf
3018 init-if-undefined Initialize a convenience variable, but
3019 only if it doesn't already have a value.
3021 The following commands are presently only implemented for native GNU/Linux:
3023 checkpoint Save a snapshot of the program state.
3025 restart <n> Return the program state to a
3026 previously saved state.
3028 info checkpoints List currently saved checkpoints.
3030 delete-checkpoint <n> Delete a previously saved checkpoint.
3032 set|show detach-on-fork Tell gdb whether to detach from a newly
3033 forked process, or to keep debugging it.
3035 info forks List forks of the user program that
3036 are available to be debugged.
3038 fork <n> Switch to debugging one of several
3039 forks of the user program that are
3040 available to be debugged.
3042 delete-fork <n> Delete a fork from the list of forks
3043 that are available to be debugged (and
3044 kill the forked process).
3046 detach-fork <n> Delete a fork from the list of forks
3047 that are available to be debugged (and
3048 allow the process to continue).
3052 Morpho Technologies ms2 ms1-elf
3054 * Improved Windows host support
3056 GDB now builds as a cross debugger hosted on i686-mingw32, including
3057 native console support, and remote communications using either
3058 network sockets or serial ports.
3060 * Improved Modula-2 language support
3062 GDB can now print most types in the Modula-2 syntax. This includes:
3063 basic types, set types, record types, enumerated types, range types,
3064 pointer types and ARRAY types. Procedure var parameters are correctly
3065 printed and hexadecimal addresses and character constants are also
3066 written in the Modula-2 syntax. Best results can be obtained by using
3067 GNU Modula-2 together with the -gdwarf-2 command line option.
3071 The ARM rdi-share module.
3073 The Netware NLM debug server.
3075 *** Changes in GDB 6.4
3077 * New native configurations
3079 OpenBSD/arm arm*-*-openbsd*
3080 OpenBSD/mips64 mips64-*-openbsd*
3084 Morpho Technologies ms1 ms1-elf
3086 * New command line options
3088 --batch-silent As for --batch, but totally silent.
3089 --return-child-result The debugger will exist with the same value
3090 the child (debugged) program exited with.
3091 --eval-command COMMAND, -ex COMMAND
3092 Execute a single GDB CLI command. This may be
3093 specified multiple times and in conjunction
3094 with the --command (-x) option.
3096 * Deprecated commands removed
3098 The following commands, that were deprecated in 2000, have been
3102 set|show arm disassembly-flavor set|show arm disassembler
3103 othernames set arm disassembler
3104 set|show remotedebug set|show debug remote
3105 set|show archdebug set|show debug arch
3106 set|show eventdebug set|show debug event
3109 * New BSD user-level threads support
3111 It is now possible to debug programs using the user-level threads
3112 library on OpenBSD and FreeBSD. Currently supported (target)
3115 FreeBSD/amd64 x86_64-*-freebsd*
3116 FreeBSD/i386 i386-*-freebsd*
3117 OpenBSD/i386 i386-*-openbsd*
3119 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3120 are not yet supported.
3122 * New support for Matsushita MN10300 w/sim added
3123 (Work in progress). mn10300-elf.
3125 * REMOVED configurations and files
3127 VxWorks and the XDR protocol *-*-vxworks
3128 Motorola MCORE mcore-*-*
3129 National Semiconductor NS32000 ns32k-*-*
3131 * New "set print array-indexes" command
3133 After turning this setting "on", GDB prints the index of each element
3134 when displaying arrays. The default is "off" to preserve the previous
3137 * VAX floating point support
3139 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3141 * User-defined command support
3143 In addition to using $arg0..$arg9 for argument passing, it is now possible
3144 to use $argc to determine now many arguments have been passed. See the
3145 section on user-defined commands in the user manual for more information.
3147 *** Changes in GDB 6.3:
3149 * New command line option
3151 GDB now accepts -l followed by a number to set the timeout for remote
3154 * GDB works with GCC -feliminate-dwarf2-dups
3156 GDB now supports a more compact representation of DWARF-2 debug
3157 information using DW_FORM_ref_addr references. These are produced
3158 by GCC with the option -feliminate-dwarf2-dups and also by some
3159 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3160 to use -feliminate-dwarf2-dups.
3162 * Internationalization
3164 When supported by the host system, GDB will be built with
3165 internationalization (libintl). The task of marking up the sources is
3166 continued, we're looking forward to our first translation.
3170 Initial support for debugging programs compiled with the GNAT
3171 implementation of the Ada programming language has been integrated
3172 into GDB. In this release, support is limited to expression evaluation.
3174 * New native configurations
3176 GNU/Linux/m32r m32r-*-linux-gnu
3180 GDB's remote protocol now includes support for the 'p' packet. This
3181 packet is used to fetch individual registers from a remote inferior.
3183 * END-OF-LIFE registers[] compatibility module
3185 GDB's internal register infrastructure has been completely rewritten.
3186 The new infrastructure making possible the implementation of key new
3187 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3190 GDB 6.3 will be the last release to include the the registers[]
3191 compatibility module that allowed out-of-date configurations to
3192 continue to work. This change directly impacts the following
3202 powerpc bdm protocol
3204 Unless there is activity to revive these configurations, they will be
3205 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3207 * OBSOLETE configurations and files
3209 Configurations that have been declared obsolete in this release have
3210 been commented out. Unless there is activity to revive these
3211 configurations, the next release of GDB will have their sources
3212 permanently REMOVED.
3221 *** Changes in GDB 6.2.1:
3223 * MIPS `break main; run' gave an heuristic-fence-post warning
3225 When attempting to run even a simple program, a warning about
3226 heuristic-fence-post being hit would be reported. This problem has
3229 * MIPS IRIX 'long double' crashed GDB
3231 When examining a long double variable, GDB would get a segmentation
3232 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3233 IRIX long double values).
3237 A bug in the VAX stack code was causing problems with the "next"
3238 command. This problem has been fixed.
3240 *** Changes in GDB 6.2:
3242 * Fix for ``many threads''
3244 On GNU/Linux systems that use the NPTL threads library, a program
3245 rapidly creating and deleting threads would confuse GDB leading to the
3248 ptrace: No such process.
3249 thread_db_get_info: cannot get thread info: generic error
3251 This problem has been fixed.
3253 * "-async" and "-noasync" options removed.
3255 Support for the broken "-noasync" option has been removed (it caused
3258 * New ``start'' command.
3260 This command runs the program until the begining of the main procedure.
3262 * New BSD Kernel Data Access Library (libkvm) interface
3264 Using ``target kvm'' it is now possible to debug kernel core dumps and
3265 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3266 platforms. Currently supported (native-only) configurations are:
3268 FreeBSD/amd64 x86_64-*-freebsd*
3269 FreeBSD/i386 i?86-*-freebsd*
3270 NetBSD/i386 i?86-*-netbsd*
3271 NetBSD/m68k m68*-*-netbsd*
3272 NetBSD/sparc sparc-*-netbsd*
3273 OpenBSD/amd64 x86_64-*-openbsd*
3274 OpenBSD/i386 i?86-*-openbsd*
3275 OpenBSD/m68k m68*-openbsd*
3276 OpenBSD/sparc sparc-*-openbsd*
3278 * Signal trampoline code overhauled
3280 Many generic problems with GDB's signal handling code have been fixed.
3281 These include: backtraces through non-contiguous stacks; recognition
3282 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3283 call; backtrace through a signal trampoline; step into and out of
3284 signal handlers; and single-stepping in the signal trampoline.
3286 Please note that kernel bugs are a limiting factor here. These
3287 features have been shown to work on an s390 GNU/Linux system that
3288 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3290 * Cygwin support for DWARF 2 added.
3292 * New native configurations
3294 GNU/Linux/hppa hppa*-*-linux*
3295 OpenBSD/hppa hppa*-*-openbsd*
3296 OpenBSD/m68k m68*-*-openbsd*
3297 OpenBSD/m88k m88*-*-openbsd*
3298 OpenBSD/powerpc powerpc-*-openbsd*
3299 NetBSD/vax vax-*-netbsd*
3300 OpenBSD/vax vax-*-openbsd*
3302 * END-OF-LIFE frame compatibility module
3304 GDB's internal frame infrastructure has been completely rewritten.
3305 The new infrastructure making it possible to support key new features
3306 including DWARF 2 Call Frame Information. To aid in the task of
3307 migrating old configurations to this new infrastructure, a
3308 compatibility module, that allowed old configurations to continue to
3309 work, was also included.
3311 GDB 6.2 will be the last release to include this frame compatibility
3312 module. This change directly impacts the following configurations:
3322 Unless there is activity to revive these configurations, they will be
3323 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3325 * REMOVED configurations and files
3327 Sun 3, running SunOS 3 m68*-*-sunos3*
3328 Sun 3, running SunOS 4 m68*-*-sunos4*
3329 Sun 2, running SunOS 3 m68000-*-sunos3*
3330 Sun 2, running SunOS 4 m68000-*-sunos4*
3331 Motorola 680x0 running LynxOS m68*-*-lynxos*
3332 AT&T 3b1/Unix pc m68*-att-*
3333 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3334 decstation mips-dec-* mips-little-*
3335 riscos mips-*-riscos* mips-*-sysv*
3336 sonymips mips-sony-*
3337 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3339 *** Changes in GDB 6.1.1:
3341 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3343 The TUI (Text-mode User Interface) is now built as part of a default
3344 GDB configuration. It is enabled by either selecting the TUI with the
3345 command line option "-i=tui" or by running the separate "gdbtui"
3346 program. For more information on the TUI, see the manual "Debugging
3349 * Pending breakpoint support (also included in GDB 6.1)
3351 Support has been added to allow you to specify breakpoints in shared
3352 libraries that have not yet been loaded. If a breakpoint location
3353 cannot be found, and the "breakpoint pending" option is set to auto,
3354 GDB queries you if you wish to make the breakpoint pending on a future
3355 shared-library load. If and when GDB resolves the breakpoint symbol,
3356 the pending breakpoint is removed as one or more regular breakpoints
3359 Pending breakpoints are very useful for GCJ Java debugging.
3361 * Fixed ISO-C build problems
3363 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3364 non ISO-C code that stopped them being built using a more strict ISO-C
3365 compiler (e.g., IBM's C compiler).
3367 * Fixed build problem on IRIX 5
3369 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3370 wasn't able to compile compile on an IRIX 5 system.
3372 * Added execute permission to gdb/gdbserver/configure
3374 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3375 permission. This bug would cause configure to fail on a number of
3376 systems (Solaris, IRIX). Ref: server/519.
3378 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3380 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3381 has been updated to use constant array sizes.
3383 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3385 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3386 its generated DWARF Call Frame Info. This encoding was causing GDB to
3387 panic, that panic has been fixed. Ref: gdb/1628.
3389 * Fixed a problem when examining parameters in shared library code.
3391 When examining parameters in optimized shared library code generated
3392 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3393 not available''. GDB now correctly displays the variable's value.
3395 *** Changes in GDB 6.1:
3397 * Removed --with-mmalloc
3399 Support for the mmalloc memory manager has been removed, as it
3400 conflicted with the internal gdb byte cache.
3402 * Changes in AMD64 configurations
3404 The AMD64 target now includes the %cs and %ss registers. As a result
3405 the AMD64 remote protocol has changed; this affects the floating-point
3406 and SSE registers. If you rely on those registers for your debugging,
3407 you should upgrade gdbserver on the remote side.
3409 * Revised SPARC target
3411 The SPARC target has been completely revised, incorporating the
3412 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3413 support for LynxOS and SunOS 4 has been dropped. Calling functions
3414 from within GDB on operating systems with a non-executable stack
3415 (Solaris, OpenBSD) now works.
3419 GDB has a new C++ demangler which does a better job on the mangled
3420 names generated by current versions of g++. It also runs faster, so
3421 with this and other changes gdb should now start faster on large C++
3424 * DWARF 2 Location Expressions
3426 GDB support for location expressions has been extended to support function
3427 arguments and frame bases. Older versions of GDB could crash when they
3430 * C++ nested types and namespaces
3432 GDB's support for nested types and namespaces in C++ has been
3433 improved, especially if you use the DWARF 2 debugging format. (This
3434 is the default for recent versions of GCC on most platforms.)
3435 Specifically, if you have a class "Inner" defined within a class or
3436 namespace "Outer", then GDB realizes that the class's name is
3437 "Outer::Inner", not simply "Inner". This should greatly reduce the
3438 frequency of complaints about not finding RTTI symbols. In addition,
3439 if you are stopped at inside of a function defined within a namespace,
3440 GDB modifies its name lookup accordingly.
3442 * New native configurations
3444 NetBSD/amd64 x86_64-*-netbsd*
3445 OpenBSD/amd64 x86_64-*-openbsd*
3446 OpenBSD/alpha alpha*-*-openbsd*
3447 OpenBSD/sparc sparc-*-openbsd*
3448 OpenBSD/sparc64 sparc64-*-openbsd*
3450 * New debugging protocols
3452 M32R with SDI protocol m32r-*-elf*
3454 * "set prompt-escape-char" command deleted.
3456 The command "set prompt-escape-char" has been deleted. This command,
3457 and its very obscure effet on GDB's prompt, was never documented,
3458 tested, nor mentioned in the NEWS file.
3460 * OBSOLETE configurations and files
3462 Configurations that have been declared obsolete in this release have
3463 been commented out. Unless there is activity to revive these
3464 configurations, the next release of GDB will have their sources
3465 permanently REMOVED.
3467 Sun 3, running SunOS 3 m68*-*-sunos3*
3468 Sun 3, running SunOS 4 m68*-*-sunos4*
3469 Sun 2, running SunOS 3 m68000-*-sunos3*
3470 Sun 2, running SunOS 4 m68000-*-sunos4*
3471 Motorola 680x0 running LynxOS m68*-*-lynxos*
3472 AT&T 3b1/Unix pc m68*-att-*
3473 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3474 decstation mips-dec-* mips-little-*
3475 riscos mips-*-riscos* mips-*-sysv*
3476 sonymips mips-sony-*
3477 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3479 * REMOVED configurations and files
3481 SGI Irix-4.x mips-sgi-irix4 or iris4
3482 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3483 Z8000 simulator z8k-zilog-none or z8ksim
3484 Matsushita MN10200 w/simulator mn10200-*-*
3485 H8/500 simulator h8500-hitachi-hms or h8500hms
3486 HP/PA running BSD hppa*-*-bsd*
3487 HP/PA running OSF/1 hppa*-*-osf*
3488 HP/PA Pro target hppa*-*-pro*
3489 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3490 386BSD i[3456]86-*-bsd*
3491 Sequent family i[3456]86-sequent-sysv4*
3492 i[3456]86-sequent-sysv*
3493 i[3456]86-sequent-bsd*
3494 SPARC running LynxOS sparc-*-lynxos*
3495 SPARC running SunOS 4 sparc-*-sunos4*
3496 Tsqware Sparclet sparclet-*-*
3497 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3499 *** Changes in GDB 6.0:
3503 Support for debugging the Objective-C programming language has been
3504 integrated into GDB.
3506 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3508 DWARF 2's Call Frame Information makes available compiler generated
3509 information that more exactly describes the program's run-time stack.
3510 By using this information, GDB is able to provide more robust stack
3513 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3514 have been updated to use a new backtrace mechanism which includes
3515 DWARF 2 CFI support.
3519 GDB's remote protocol has been extended to include support for hosted
3520 file I/O (where the remote target uses GDB's file system). See GDB's
3521 remote protocol documentation for details.
3523 * All targets using the new architecture framework.
3525 All of GDB's targets have been updated to use the new internal
3526 architecture framework. The way is now open for future GDB releases
3527 to include cross-architecture native debugging support (i386 on amd64,
3530 * GNU/Linux's Thread Local Storage (TLS)
3532 GDB now includes support for for the GNU/Linux implementation of
3533 per-thread variables.
3535 * GNU/Linux's Native POSIX Thread Library (NPTL)
3537 GDB's thread code has been updated to work with either the new
3538 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3540 * Separate debug info.
3542 GDB, in conjunction with BINUTILS, now supports a mechanism for
3543 automatically loading debug information from a separate file. Instead
3544 of shipping full debug and non-debug versions of system libraries,
3545 system integrators can now instead ship just the stripped libraries
3546 and optional debug files.
3548 * DWARF 2 Location Expressions
3550 DWARF 2 Location Expressions allow the compiler to more completely
3551 describe the location of variables (even in optimized code) to the
3554 GDB now includes preliminary support for location expressions (support
3555 for DW_OP_piece is still missing).
3559 A number of long standing bugs that caused GDB to die while starting a
3560 Java application have been fixed. GDB's Java support is now
3561 considered "useable".
3563 * GNU/Linux support for fork, vfork, and exec.
3565 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3566 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3569 * GDB supports logging output to a file
3571 There are two new commands, "set logging" and "show logging", which can be
3572 used to capture GDB's output to a file.
3574 * The meaning of "detach" has changed for gdbserver
3576 The "detach" command will now resume the application, as documented. To
3577 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3580 * d10v, m68hc11 `regs' command deprecated
3582 The `info registers' command has been updated so that it displays the
3583 registers using a format identical to the old `regs' command.
3587 A new command, "maint set profile on/off", has been added. This command can
3588 be used to enable or disable profiling while running GDB, to profile a
3589 session or a set of commands. In addition there is a new configure switch,
3590 "--enable-profiling", which will cause GDB to be compiled with profiling
3591 data, for more informative profiling results.
3593 * Default MI syntax changed to "mi2".
3595 The default MI (machine interface) syntax, enabled by the command line
3596 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3597 "mi1", can be enabled by specifying the option "-i=mi1".
3599 Support for the original "mi0" syntax (included in GDB 5.0) has been
3602 Fix for gdb/192: removed extraneous space when displaying frame level.
3603 Fix for gdb/672: update changelist is now output in mi list format.
3604 Fix for gdb/702: a -var-assign that updates the value now shows up
3605 in a subsequent -var-update.
3607 * New native configurations.
3609 FreeBSD/amd64 x86_64-*-freebsd*
3611 * Multi-arched targets.
3613 HP/PA HPUX11 hppa*-*-hpux*
3614 Renesas M32R/D w/simulator m32r-*-elf*
3616 * OBSOLETE configurations and files
3618 Configurations that have been declared obsolete in this release have
3619 been commented out. Unless there is activity to revive these
3620 configurations, the next release of GDB will have their sources
3621 permanently REMOVED.
3623 Z8000 simulator z8k-zilog-none or z8ksim
3624 Matsushita MN10200 w/simulator mn10200-*-*
3625 H8/500 simulator h8500-hitachi-hms or h8500hms
3626 HP/PA running BSD hppa*-*-bsd*
3627 HP/PA running OSF/1 hppa*-*-osf*
3628 HP/PA Pro target hppa*-*-pro*
3629 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3630 Sequent family i[3456]86-sequent-sysv4*
3631 i[3456]86-sequent-sysv*
3632 i[3456]86-sequent-bsd*
3633 Tsqware Sparclet sparclet-*-*
3634 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3636 * REMOVED configurations and files
3639 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3640 IBM AIX PS/2 i[3456]86-*-aix
3641 i386 running Mach 3.0 i[3456]86-*-mach3*
3642 i386 running Mach i[3456]86-*-mach*
3643 i386 running OSF/1 i[3456]86-*osf1mk*
3644 HP/Apollo 68k Family m68*-apollo*-sysv*,
3646 m68*-hp-bsd*, m68*-hp-hpux*
3647 Argonaut Risc Chip (ARC) arc-*-*
3648 Mitsubishi D30V d30v-*-*
3649 Fujitsu FR30 fr30-*-elf*
3650 OS/9000 i[34]86-*-os9k
3651 I960 with MON960 i960-*-coff
3653 * MIPS $fp behavior changed
3655 The convenience variable $fp, for the MIPS, now consistently returns
3656 the address of the current frame's base. Previously, depending on the
3657 context, $fp could refer to either $sp or the current frame's base
3658 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3659 The GNU Source-Level Debugger''.
3661 *** Changes in GDB 5.3:
3663 * GNU/Linux shared library multi-threaded performance improved.
3665 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3666 `/proc', in preference to `ptrace' for memory reads. This may result
3667 in an improvement in the start-up time of multi-threaded, shared
3668 library applications when run under GDB. One GDB user writes: ``loads
3669 shared libs like mad''.
3671 * ``gdbserver'' now supports multi-threaded applications on some targets
3673 Support for debugging multi-threaded applications which use
3674 the GNU/Linux LinuxThreads package has been added for
3675 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3676 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3678 * GDB now supports C/C++ preprocessor macros.
3680 GDB now expands preprocessor macro invocations in C/C++ expressions,
3681 and provides various commands for showing macro definitions and how
3684 The new command `macro expand EXPRESSION' expands any macro
3685 invocations in expression, and shows the result.
3687 The new command `show macro MACRO-NAME' shows the definition of the
3688 macro named MACRO-NAME, and where it was defined.
3690 Most compilers don't include information about macros in the debugging
3691 information by default. In GCC 3.1, for example, you need to compile
3692 your program with the options `-gdwarf-2 -g3'. If the macro
3693 information is present in the executable, GDB will read it.
3695 * Multi-arched targets.
3697 DEC Alpha (partial) alpha*-*-*
3698 DEC VAX (partial) vax-*-*
3700 National Semiconductor NS32000 (partial) ns32k-*-*
3701 Motorola 68000 (partial) m68k-*-*
3702 Motorola MCORE mcore-*-*
3706 Fujitsu FRV architecture added by Red Hat frv*-*-*
3709 * New native configurations
3711 Alpha NetBSD alpha*-*-netbsd*
3712 SH NetBSD sh*-*-netbsdelf*
3713 MIPS NetBSD mips*-*-netbsd*
3714 UltraSPARC NetBSD sparc64-*-netbsd*
3716 * OBSOLETE configurations and files
3718 Configurations that have been declared obsolete in this release have
3719 been commented out. Unless there is activity to revive these
3720 configurations, the next release of GDB will have their sources
3721 permanently REMOVED.
3723 Mitsubishi D30V d30v-*-*
3724 OS/9000 i[34]86-*-os9k
3725 IBM AIX PS/2 i[3456]86-*-aix
3726 Fujitsu FR30 fr30-*-elf*
3727 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3728 Argonaut Risc Chip (ARC) arc-*-*
3729 i386 running Mach 3.0 i[3456]86-*-mach3*
3730 i386 running Mach i[3456]86-*-mach*
3731 i386 running OSF/1 i[3456]86-*osf1mk*
3732 HP/Apollo 68k Family m68*-apollo*-sysv*,
3734 m68*-hp-bsd*, m68*-hp-hpux*
3735 I960 with MON960 i960-*-coff
3737 * OBSOLETE languages
3739 CHILL, a Pascal like language used by telecommunications companies.
3741 * REMOVED configurations and files
3743 AMD 29k family via UDI a29k-amd-udi, udi29k
3744 A29K VxWorks a29k-*-vxworks
3745 AMD 29000 embedded, using EBMON a29k-none-none
3746 AMD 29000 embedded with COFF a29k-none-coff
3747 AMD 29000 embedded with a.out a29k-none-aout
3749 testsuite/gdb.hp/gdb.threads-hp/ directory
3751 * New command "set max-user-call-depth <nnn>"
3753 This command allows the user to limit the call depth of user-defined
3754 commands. The default is 1024.
3756 * Changes in FreeBSD/i386 native debugging.
3758 Support for the "generate-core-file" has been added.
3760 * New commands "dump", "append", and "restore".
3762 These commands allow data to be copied from target memory
3763 to a bfd-format or binary file (dump and append), and back
3764 from a file into memory (restore).
3766 * Improved "next/step" support on multi-processor Alpha Tru64.
3768 The previous single-step mechanism could cause unpredictable problems,
3769 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3770 of a software single-step mechanism prevents this.
3772 *** Changes in GDB 5.2.1:
3780 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3781 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3782 Fix, by Joel Brobecker imported from mainline.
3784 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3785 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3786 Fix, by Fred Fish, imported from mainline.
3788 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3789 Surprisingly enough, it works now.
3790 By Michal Ludvig, imported from mainline.
3792 i386 hardware watchpoint support:
3793 avoid misses on second run for some targets.
3794 By Pierre Muller, imported from mainline.
3796 *** Changes in GDB 5.2:
3798 * New command "set trust-readonly-sections on[off]".
3800 This command is a hint that tells gdb that read-only sections
3801 really are read-only (ie. that their contents will not change).
3802 In this mode, gdb will go to the object file rather than the
3803 target to read memory from read-only sections (such as ".text").
3804 This can be a significant performance improvement on some
3805 (notably embedded) targets.
3807 * New command "generate-core-file" (or "gcore").
3809 This new gdb command allows the user to drop a core file of the child
3810 process state at any time. So far it's been implemented only for
3811 GNU/Linux and Solaris, but should be relatively easily ported to other
3812 hosts. Argument is core file name (defaults to core.<pid>).
3814 * New command line option
3816 GDB now accepts --pid or -p followed by a process id.
3818 * Change in command line behavior -- corefiles vs. process ids.
3820 There is a subtle behavior in the way in which GDB handles
3821 command line arguments. The first non-flag argument is always
3822 a program to debug, but the second non-flag argument may either
3823 be a corefile or a process id. Previously, GDB would attempt to
3824 open the second argument as a corefile, and if that failed, would
3825 issue a superfluous error message and then attempt to attach it as
3826 a process. Now, if the second argument begins with a non-digit,
3827 it will be treated as a corefile. If it begins with a digit,
3828 GDB will attempt to attach it as a process, and if no such process
3829 is found, will then attempt to open it as a corefile.
3831 * Changes in ARM configurations.
3833 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3834 configuration is fully multi-arch.
3836 * New native configurations
3838 ARM NetBSD arm*-*-netbsd*
3839 x86 OpenBSD i[3456]86-*-openbsd*
3840 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3841 Sparc64 running FreeBSD sparc64-*-freebsd*
3845 Sanyo XStormy16 xstormy16-elf
3847 * OBSOLETE configurations and files
3849 Configurations that have been declared obsolete in this release have
3850 been commented out. Unless there is activity to revive these
3851 configurations, the next release of GDB will have their sources
3852 permanently REMOVED.
3854 AMD 29k family via UDI a29k-amd-udi, udi29k
3855 A29K VxWorks a29k-*-vxworks
3856 AMD 29000 embedded, using EBMON a29k-none-none
3857 AMD 29000 embedded with COFF a29k-none-coff
3858 AMD 29000 embedded with a.out a29k-none-aout
3860 testsuite/gdb.hp/gdb.threads-hp/ directory
3862 * REMOVED configurations and files
3864 TI TMS320C80 tic80-*-*
3866 PowerPC Solaris powerpcle-*-solaris*
3867 PowerPC Windows NT powerpcle-*-cygwin32
3868 PowerPC Netware powerpc-*-netware*
3869 Harris/CXUX m88k m88*-harris-cxux*
3870 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3871 ns32k-utek-sysv* ns32k-utek-*
3872 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3873 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3874 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3875 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3876 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3878 * Changes to command line processing
3880 The new `--args' feature can be used to specify command-line arguments
3881 for the inferior from gdb's command line.
3883 * Changes to key bindings
3885 There is a new `operate-and-get-next' function bound to `C-o'.
3887 *** Changes in GDB 5.1.1
3889 Fix compile problem on DJGPP.
3891 Fix a problem with floating-point registers on the i386 being
3894 Fix to stop GDB crashing on .debug_str debug info.
3896 Numerous documentation fixes.
3898 Numerous testsuite fixes.
3900 *** Changes in GDB 5.1:
3902 * New native configurations
3904 Alpha FreeBSD alpha*-*-freebsd*
3905 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3906 MIPS GNU/Linux mips*-*-linux*
3907 MIPS SGI Irix 6.x mips*-sgi-irix6*
3908 ia64 AIX ia64-*-aix*
3909 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3913 Motorola 68HC11 and 68HC12 m68hc11-elf
3915 UltraSparc running GNU/Linux sparc64-*-linux*
3917 * OBSOLETE configurations and files
3919 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3920 Harris/CXUX m88k m88*-harris-cxux*
3921 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3922 ns32k-utek-sysv* ns32k-utek-*
3923 TI TMS320C80 tic80-*-*
3925 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3926 PowerPC Solaris powerpcle-*-solaris*
3927 PowerPC Windows NT powerpcle-*-cygwin32
3928 PowerPC Netware powerpc-*-netware*
3929 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3930 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3931 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3932 Apple Macintosh (MPW) host N/A
3934 stuff.c (Program to stuff files into a specially prepared space in kdb)
3935 kdb-start.c (Main loop for the standalone kernel debugger)
3937 Configurations that have been declared obsolete in this release have
3938 been commented out. Unless there is activity to revive these
3939 configurations, the next release of GDB will have their sources
3940 permanently REMOVED.
3942 * REMOVED configurations and files
3944 Altos 3068 m68*-altos-*
3945 Convex c1-*-*, c2-*-*
3947 ARM RISCix arm-*-* (as host)
3951 * GDB has been converted to ISO C.
3953 GDB's source code has been converted to ISO C. In particular, the
3954 sources are fully protoized, and rely on standard headers being
3959 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3961 * The MI enabled by default.
3963 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3964 revised and enabled by default. Packages which use GDB as a debugging
3965 engine behind a UI or another front end are encouraged to switch to
3966 using the GDB/MI interface, instead of the old annotations interface
3967 which is now deprecated.
3969 * Support for debugging Pascal programs.
3971 GDB now includes support for debugging Pascal programs. The following
3972 main features are supported:
3974 - Pascal-specific data types such as sets;
3976 - automatic recognition of Pascal sources based on file-name
3979 - Pascal-style display of data types, variables, and functions;
3981 - a Pascal expression parser.
3983 However, some important features are not yet supported.
3985 - Pascal string operations are not supported at all;
3987 - there are some problems with boolean types;
3989 - Pascal type hexadecimal constants are not supported
3990 because they conflict with the internal variables format;
3992 - support for Pascal objects and classes is not full yet;
3994 - unlike Pascal, GDB is case-sensitive for symbol names.
3996 * Changes in completion.
3998 Commands such as `shell', `run' and `set args', which pass arguments
3999 to inferior programs, now complete on file names, similar to what
4000 users expect at the shell prompt.
4002 Commands which accept locations, such as `disassemble', `print',
4003 `breakpoint', `until', etc. now complete on filenames as well as
4004 program symbols. Thus, if you type "break foob TAB", and the source
4005 files linked into the programs include `foobar.c', that file name will
4006 be one of the candidates for completion. However, file names are not
4007 considered for completion after you typed a colon that delimits a file
4008 name from a name of a function in that file, as in "break foo.c:bar".
4010 `set demangle-style' completes on available demangling styles.
4012 * New platform-independent commands:
4014 It is now possible to define a post-hook for a command as well as a
4015 hook that runs before the command. For more details, see the
4016 documentation of `hookpost' in the GDB manual.
4018 * Changes in GNU/Linux native debugging.
4020 Support for debugging multi-threaded programs has been completely
4021 revised for all platforms except m68k and sparc. You can now debug as
4022 many threads as your system allows you to have.
4024 Attach/detach is supported for multi-threaded programs.
4026 Support for SSE registers was added for x86. This doesn't work for
4027 multi-threaded programs though.
4029 * Changes in MIPS configurations.
4031 Multi-arch support is enabled for all MIPS configurations.
4033 GDB can now be built as native debugger on SGI Irix 6.x systems for
4034 debugging n32 executables. (Debugging 64-bit executables is not yet
4037 * Unified support for hardware watchpoints in all x86 configurations.
4039 Most (if not all) native x86 configurations support hardware-assisted
4040 breakpoints and watchpoints in a unified manner. This support
4041 implements debug register sharing between watchpoints, which allows to
4042 put a virtually infinite number of watchpoints on the same address,
4043 and also supports watching regions up to 16 bytes with several debug
4046 The new maintenance command `maintenance show-debug-regs' toggles
4047 debugging print-outs in functions that insert, remove, and test
4048 watchpoints and hardware breakpoints.
4050 * Changes in the DJGPP native configuration.
4052 New command ``info dos sysinfo'' displays assorted information about
4053 the CPU, OS, memory, and DPMI server.
4055 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4056 display information about segment descriptors stored in GDT, LDT, and
4059 New commands ``info dos pde'' and ``info dos pte'' display entries
4060 from Page Directory and Page Tables (for now works with CWSDPMI only).
4061 New command ``info dos address-pte'' displays the Page Table entry for
4062 a given linear address.
4064 GDB can now pass command lines longer than 126 characters to the
4065 program being debugged (requires an update to the libdbg.a library
4066 which is part of the DJGPP development kit).
4068 DWARF2 debug info is now supported.
4070 It is now possible to `step' and `next' through calls to `longjmp'.
4072 * Changes in documentation.
4074 All GDB documentation was converted to GFDL, the GNU Free
4075 Documentation License.
4077 Tracepoints-related commands are now fully documented in the GDB
4080 TUI, the Text-mode User Interface, is now documented in the manual.
4082 Tracepoints-related commands are now fully documented in the GDB
4085 The "GDB Internals" manual now has an index. It also includes
4086 documentation of `ui_out' functions, GDB coding standards, x86
4087 hardware watchpoints, and memory region attributes.
4089 * GDB's version number moved to ``version.in''
4091 The Makefile variable VERSION has been replaced by the file
4092 ``version.in''. People creating GDB distributions should update the
4093 contents of this file.
4097 GUD support is now a standard part of the EMACS distribution.
4099 *** Changes in GDB 5.0:
4101 * Improved support for debugging FP programs on x86 targets
4103 Unified and much-improved support for debugging floating-point
4104 programs on all x86 targets. In particular, ``info float'' now
4105 displays the FP registers in the same format on all x86 targets, with
4106 greater level of detail.
4108 * Improvements and bugfixes in hardware-assisted watchpoints
4110 It is now possible to watch array elements, struct members, and
4111 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4112 on x86 targets no longer erroneously trigger when the address is
4115 * Improvements in the native DJGPP version of GDB
4117 The distribution now includes all the scripts and auxiliary files
4118 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4119 machines ``out of the box''.
4121 The DJGPP version can now debug programs that use signals. It is
4122 possible to catch signals that happened in the debuggee, deliver
4123 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4124 would kill the program being debugged.) Programs that hook hardware
4125 interrupts (keyboard, timer, etc.) can also be debugged.
4127 It is now possible to debug DJGPP programs that redirect their
4128 standard handles or switch them to raw (as opposed to cooked) mode, or
4129 even close them. The command ``run < foo > bar'' works as expected,
4130 and ``info terminal'' reports useful information about the debuggee's
4131 terminal, including raw/cooked mode, redirection, etc.
4133 The DJGPP version now uses termios functions for console I/O, which
4134 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4137 DOS-style file names with drive letters are now fully supported by
4140 It is now possible to debug DJGPP programs that switch their working
4141 directory. It is also possible to rerun the debuggee any number of
4142 times without restarting GDB; thus, you can use the same setup,
4143 breakpoints, etc. for many debugging sessions.
4145 * New native configurations
4147 ARM GNU/Linux arm*-*-linux*
4148 PowerPC GNU/Linux powerpc-*-linux*
4152 Motorola MCore mcore-*-*
4153 x86 VxWorks i[3456]86-*-vxworks*
4154 PowerPC VxWorks powerpc-*-vxworks*
4155 TI TMS320C80 tic80-*-*
4157 * OBSOLETE configurations
4159 Altos 3068 m68*-altos-*
4160 Convex c1-*-*, c2-*-*
4162 ARM RISCix arm-*-* (as host)
4165 Configurations that have been declared obsolete will be commented out,
4166 but the code will be left in place. If there is no activity to revive
4167 these configurations before the next release of GDB, the sources will
4168 be permanently REMOVED.
4170 * Gould support removed
4172 Support for the Gould PowerNode and NP1 has been removed.
4174 * New features for SVR4
4176 On SVR4 native platforms (such as Solaris), if you attach to a process
4177 without first loading a symbol file, GDB will now attempt to locate and
4178 load symbols from the running process's executable file.
4180 * Many C++ enhancements
4182 C++ support has been greatly improved. Overload resolution now works properly
4183 in almost all cases. RTTI support is on the way.
4185 * Remote targets can connect to a sub-program
4187 A popen(3) style serial-device has been added. This device starts a
4188 sub-process (such as a stand-alone simulator) and then communicates
4189 with that. The sub-program to run is specified using the syntax
4190 ``|<program> <args>'' vis:
4192 (gdb) set remotedebug 1
4193 (gdb) target extended-remote |mn10300-elf-sim program-args
4195 * MIPS 64 remote protocol
4197 A long standing bug in the mips64 remote protocol where by GDB
4198 expected certain 32 bit registers (ex SR) to be transfered as 32
4199 instead of 64 bits has been fixed.
4201 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4202 added to provide backward compatibility with older versions of GDB.
4204 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4206 The command ``set remotebinarydownload'' command has been replaced by
4207 ``set remote X-packet''. Other commands in ``set remote'' family
4208 include ``set remote P-packet''.
4210 * Breakpoint commands accept ranges.
4212 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4213 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4214 ``tracepoint passcount'' also accepts a range of tracepoints.
4216 * ``apropos'' command added.
4218 The ``apropos'' command searches through command names and
4219 documentation strings, printing out matches, making it much easier to
4220 try to find a command that does what you are looking for.
4224 A new machine oriented interface (MI) has been added to GDB. This
4225 interface is designed for debug environments running GDB as a separate
4226 process. This is part of the long term libGDB project. See the
4227 "GDB/MI" chapter of the GDB manual for further information. It can be
4228 enabled by configuring with:
4230 .../configure --enable-gdbmi
4232 *** Changes in GDB-4.18:
4234 * New native configurations
4236 HP-UX 10.20 hppa*-*-hpux10.20
4237 HP-UX 11.x hppa*-*-hpux11.0*
4238 M68K GNU/Linux m68*-*-linux*
4242 Fujitsu FR30 fr30-*-elf*
4243 Intel StrongARM strongarm-*-*
4244 Mitsubishi D30V d30v-*-*
4246 * OBSOLETE configurations
4248 Gould PowerNode, NP1 np1-*-*, pn-*-*
4250 Configurations that have been declared obsolete will be commented out,
4251 but the code will be left in place. If there is no activity to revive
4252 these configurations before the next release of GDB, the sources will
4253 be permanently REMOVED.
4257 As a compatibility experiment, GDB's source files buildsym.h and
4258 buildsym.c have been converted to pure standard C, no longer
4259 containing any K&R compatibility code. We believe that all systems in
4260 use today either come with a standard C compiler, or have a GCC port
4261 available. If this is not true, please report the affected
4263 information about getting a standard C compiler if you don't have one
4268 GDB now uses readline 2.2.
4270 * set extension-language
4272 You can now control the mapping between filename extensions and source
4273 languages by using the `set extension-language' command. For instance,
4274 you can ask GDB to treat .c files as C++ by saying
4275 set extension-language .c c++
4276 The command `info extensions' lists all of the recognized extensions
4277 and their associated languages.
4279 * Setting processor type for PowerPC and RS/6000
4281 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4282 you can use the `set processor' command to specify what variant of the
4283 PowerPC family you are debugging. The command
4287 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4288 following PowerPC and RS6000 variants:
4290 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4291 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4293 403GC IBM PowerPC 403GC
4294 505 Motorola PowerPC 505
4295 860 Motorola PowerPC 860 or 850
4296 601 Motorola PowerPC 601
4297 602 Motorola PowerPC 602
4298 603 Motorola/IBM PowerPC 603 or 603e
4299 604 Motorola PowerPC 604 or 604e
4300 750 Motorola/IBM PowerPC 750 or 750
4302 At the moment, this command just tells GDB what to name the
4303 special-purpose processor registers. Since almost all the affected
4304 registers are inaccessible to user-level programs, this command is
4305 only useful for remote debugging in its present form.
4309 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4310 more extensive support for HP-UX. Added features include shared
4311 library support, kernel threads and hardware watchpoints for 11.00,
4312 support for HP's ANSI C and C++ compilers, and a compatibility mode
4313 for xdb and dbx commands.
4317 HP's donation includes the new concept of catchpoints, which is a
4318 generalization of the old catch command. On HP-UX, it is now possible
4319 to catch exec, fork, and vfork, as well as library loading.
4321 This means that the existing catch command has changed; its first
4322 argument now specifies the type of catch to be set up. See the
4323 output of "help catch" for a list of catchpoint types.
4325 * Debugging across forks
4327 On HP-UX, you can choose which process to debug when a fork() happens
4332 HP has donated a curses-based terminal user interface (TUI). To get
4333 it, build with --enable-tui. Although this can be enabled for any
4334 configuration, at present it only works for native HP debugging.
4336 * GDB remote protocol additions
4338 A new protocol packet 'X' that writes binary data is now available.
4339 Default behavior is to try 'X', then drop back to 'M' if the stub
4340 fails to respond. The settable variable `remotebinarydownload'
4341 allows explicit control over the use of 'X'.
4343 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4344 full 64-bit address. The command
4346 set remoteaddresssize 32
4348 can be used to revert to the old behaviour. For existing remote stubs
4349 the change should not be noticed, as the additional address information
4352 In order to assist in debugging stubs, you may use the maintenance
4353 command `packet' to send any text string to the stub. For instance,
4355 maint packet heythere
4357 sends the packet "$heythere#<checksum>". Note that it is very easy to
4358 disrupt a debugging session by sending the wrong packet at the wrong
4361 The compare-sections command allows you to compare section data on the
4362 target to what is in the executable file without uploading or
4363 downloading, by comparing CRC checksums.
4365 * Tracing can collect general expressions
4367 You may now collect general expressions at tracepoints. This requires
4368 further additions to the target-side stub; see tracepoint.c and
4369 doc/agentexpr.texi for further details.
4371 * mask-address variable for Mips
4373 For Mips targets, you may control the zeroing of the upper 32 bits of
4374 a 64-bit address by entering `set mask-address on'. This is mainly
4375 of interest to users of embedded R4xxx and R5xxx processors.
4377 * Higher serial baud rates
4379 GDB's serial code now allows you to specify baud rates 57600, 115200,
4380 230400, and 460800 baud. (Note that your host system may not be able
4381 to achieve all of these rates.)
4385 The i960 configuration now includes an initial implementation of a
4386 builtin simulator, contributed by Jim Wilson.
4389 *** Changes in GDB-4.17:
4391 * New native configurations
4393 Alpha GNU/Linux alpha*-*-linux*
4394 Unixware 2.x i[3456]86-unixware2*
4395 Irix 6.x mips*-sgi-irix6*
4396 PowerPC GNU/Linux powerpc-*-linux*
4397 PowerPC Solaris powerpcle-*-solaris*
4398 Sparc GNU/Linux sparc-*-linux*
4399 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4403 Argonaut Risc Chip (ARC) arc-*-*
4404 Hitachi H8/300S h8300*-*-*
4405 Matsushita MN10200 w/simulator mn10200-*-*
4406 Matsushita MN10300 w/simulator mn10300-*-*
4407 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4408 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4409 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4410 Mitsubishi D10V w/simulator d10v-*-*
4411 Mitsubishi M32R/D w/simulator m32r-*-elf*
4412 Tsqware Sparclet sparclet-*-*
4413 NEC V850 w/simulator v850-*-*
4415 * New debugging protocols
4417 ARM with RDI protocol arm*-*-*
4418 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4419 DDB and LSI variants of PMON protocol mips*-*-*
4420 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4421 PowerPC with SDS protocol powerpc{,le}-*-eabi
4422 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4426 All configurations can now understand and use the DWARF 2 debugging
4427 format. The choice is automatic, if the symbol file contains DWARF 2
4432 GDB now includes basic Java language support. This support is
4433 only useful with Java compilers that produce native machine code.
4435 * solib-absolute-prefix and solib-search-path
4437 For SunOS and SVR4 shared libraries, you may now set the prefix for
4438 loading absolute shared library symbol files, and the search path for
4439 locating non-absolute shared library symbol files.
4441 * Live range splitting
4443 GDB can now effectively debug code for which GCC has performed live
4444 range splitting as part of its optimization. See gdb/doc/LRS for
4445 more details on the expected format of the stabs information.
4449 GDB's support for the GNU Hurd, including thread debugging, has been
4450 updated to work with current versions of the Hurd.
4454 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4455 instruction set. ARM GDB automatically detects when Thumb
4456 instructions are in use, and adjusts disassembly and backtracing
4461 GDB's MIPS target configurations now handle the MIP16 16-bit
4466 GDB now includes support for overlays; if an executable has been
4467 linked such that multiple sections are based at the same address, GDB
4468 will decide which section to use for symbolic info. You can choose to
4469 control the decision manually, using overlay commands, or implement
4470 additional target-side support and use "overlay load-target" to bring
4471 in the overlay mapping. Do "help overlay" for more detail.
4475 The command "info symbol <address>" displays information about
4476 the symbol at the specified address.
4480 The standard remote protocol now includes an extension that allows
4481 asynchronous collection and display of trace data. This requires
4482 extensive support in the target-side debugging stub. Tracing mode
4483 includes a new interaction mode in GDB and new commands: see the
4484 file tracepoint.c for more details.
4488 Configurations for embedded MIPS now include a simulator contributed
4489 by Cygnus Solutions. The simulator supports the instruction sets
4490 of most MIPS variants.
4494 Sparc configurations may now include the ERC32 simulator contributed
4495 by the European Space Agency. The simulator is not built into
4496 Sparc targets by default; configure with --enable-sim to include it.
4500 For target configurations that may include multiple variants of a
4501 basic architecture (such as MIPS and SH), you may now set the
4502 architecture explicitly. "set arch" sets, "info arch" lists
4503 the possible architectures.
4505 *** Changes in GDB-4.16:
4507 * New native configurations
4509 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4510 M68K NetBSD m68k-*-netbsd*
4511 PowerPC AIX 4.x powerpc-*-aix*
4512 PowerPC MacOS powerpc-*-macos*
4513 PowerPC Windows NT powerpcle-*-cygwin32
4514 RS/6000 AIX 4.x rs6000-*-aix4*
4518 ARM with RDP protocol arm-*-*
4519 I960 with MON960 i960-*-coff
4520 MIPS VxWorks mips*-*-vxworks*
4521 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4522 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4524 Matra Sparclet sparclet-*-*
4528 The powerpc-eabi configuration now includes the PSIM simulator,
4529 contributed by Andrew Cagney, with assistance from Mike Meissner.
4530 PSIM is a very elaborate model of the PowerPC, including not only
4531 basic instruction set execution, but also details of execution unit
4532 performance and I/O hardware. See sim/ppc/README for more details.
4536 GDB now works with Solaris 2.5.
4538 * Windows 95/NT native
4540 GDB will now work as a native debugger on Windows 95 and Windows NT.
4541 To build it from source, you must use the "gnu-win32" environment,
4542 which uses a DLL to emulate enough of Unix to run the GNU tools.
4543 Further information, binaries, and sources are available at
4544 ftp.cygnus.com, under pub/gnu-win32.
4546 * dont-repeat command
4548 If a user-defined command includes the command `dont-repeat', then the
4549 command will not be repeated if the user just types return. This is
4550 useful if the command is time-consuming to run, so that accidental
4551 extra keystrokes don't run the same command many times.
4553 * Send break instead of ^C
4555 The standard remote protocol now includes an option to send a break
4556 rather than a ^C to the target in order to interrupt it. By default,
4557 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4559 * Remote protocol timeout
4561 The standard remote protocol includes a new variable `remotetimeout'
4562 that allows you to set the number of seconds before GDB gives up trying
4563 to read from the target. The default value is 2.
4565 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4567 By default GDB will automatically keep track of objects as they are
4568 loaded and unloaded by the dynamic linker. By using the command `set
4569 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4570 when shared library events occur, thus allowing you to set breakpoints
4571 in shared libraries which are explicitly loaded by the inferior.
4573 Note this feature does not work on hpux8. On hpux9 you must link
4574 /usr/lib/end.o into your program. This feature should work
4575 automatically on hpux10.
4577 * Irix 5.x hardware watchpoint support
4579 Irix 5 configurations now support the use of hardware watchpoints.
4581 * Mips protocol "SYN garbage limit"
4583 When debugging a Mips target using the `target mips' protocol, you
4584 may set the number of characters that GDB will ignore by setting
4585 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4586 every character. The default value is 1050.
4588 * Recording and replaying remote debug sessions
4590 If you set `remotelogfile' to the name of a file, gdb will write to it
4591 a recording of a remote debug session. This recording may then be
4592 replayed back to gdb using "gdbreplay". See gdbserver/README for
4593 details. This is useful when you have a problem with GDB while doing
4594 remote debugging; you can make a recording of the session and send it
4595 to someone else, who can then recreate the problem.
4597 * Speedups for remote debugging
4599 GDB includes speedups for downloading and stepping MIPS systems using
4600 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4601 and more efficient S-record downloading.
4603 * Memory use reductions and statistics collection
4605 GDB now uses less memory and reports statistics about memory usage.
4606 Try the `maint print statistics' command, for example.
4608 *** Changes in GDB-4.15:
4610 * Psymtabs for XCOFF
4612 The symbol reader for AIX GDB now uses partial symbol tables. This
4613 can greatly improve startup time, especially for large executables.
4615 * Remote targets use caching
4617 Remote targets now use a data cache to speed up communication with the
4618 remote side. The data cache could lead to incorrect results because
4619 it doesn't know about volatile variables, thus making it impossible to
4620 debug targets which use memory mapped I/O devices. `set remotecache
4621 off' turns the the data cache off.
4623 * Remote targets may have threads
4625 The standard remote protocol now includes support for multiple threads
4626 in the target system, using new protocol commands 'H' and 'T'. See
4627 gdb/remote.c for details.
4631 If GDB is configured with `--enable-netrom', then it will include
4632 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4633 acts as though it is a bank of ROM on the target board, but you can
4634 write into it over the network. GDB's support consists only of
4635 support for fast loading into the emulated ROM; to debug, you must use
4636 another protocol, such as standard remote protocol. The usual
4637 sequence is something like
4639 target nrom <netrom-hostname>
4641 target remote <netrom-hostname>:1235
4645 GDB now includes support for the Apple Macintosh, as a host only. It
4646 may be run as either an MPW tool or as a standalone application, and
4647 it can debug through the serial port. All the usual GDB commands are
4648 available, but to the target command, you must supply "serial" as the
4649 device type instead of "/dev/ttyXX". See mpw-README in the main
4650 directory for more information on how to build. The MPW configuration
4651 scripts */mpw-config.in support only a few targets, and only the
4652 mips-idt-ecoff target has been tested.
4656 GDB configuration now uses autoconf. This is not user-visible,
4657 but does simplify configuration and building.
4661 GDB now supports hpux10.
4663 *** Changes in GDB-4.14:
4665 * New native configurations
4667 x86 FreeBSD i[345]86-*-freebsd
4668 x86 NetBSD i[345]86-*-netbsd
4669 NS32k NetBSD ns32k-*-netbsd
4670 Sparc NetBSD sparc-*-netbsd
4674 A29K VxWorks a29k-*-vxworks
4675 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4676 CPU32 EST-300 emulator m68*-*-est*
4677 PowerPC ELF powerpc-*-elf
4680 * Alpha OSF/1 support for procfs
4682 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4683 possible to attach to running processes. As the mounting of the /proc
4684 filesystem is optional on the Alpha, GDB automatically determines
4685 the availability of /proc during startup. This can lead to problems
4686 if /proc is unmounted after GDB has been started.
4688 * Arguments to user-defined commands
4690 User commands may accept up to 10 arguments separated by whitespace.
4691 Arguments are accessed within the user command via $arg0..$arg9. A
4694 print $arg0 + $arg1 + $arg2
4696 To execute the command use:
4699 Defines the command "adder" which prints the sum of its three arguments.
4700 Note the arguments are text substitutions, so they may reference variables,
4701 use complex expressions, or even perform inferior function calls.
4703 * New `if' and `while' commands
4705 This makes it possible to write more sophisticated user-defined
4706 commands. Both commands take a single argument, which is the
4707 expression to evaluate, and must be followed by the commands to
4708 execute, one per line, if the expression is nonzero, the list being
4709 terminated by the word `end'. The `if' command list may include an
4710 `else' word, which causes the following commands to be executed only
4711 if the expression is zero.
4713 * Fortran source language mode
4715 GDB now includes partial support for Fortran 77. It will recognize
4716 Fortran programs and can evaluate a subset of Fortran expressions, but
4717 variables and functions may not be handled correctly. GDB will work
4718 with G77, but does not yet know much about symbols emitted by other
4721 * Better HPUX support
4723 Most debugging facilities now work on dynamic executables for HPPAs
4724 running hpux9 or later. You can attach to running dynamically linked
4725 processes, but by default the dynamic libraries will be read-only, so
4726 for instance you won't be able to put breakpoints in them. To change
4727 that behavior do the following before running the program:
4733 This will cause the libraries to be mapped private and read-write.
4734 To revert to the normal behavior, do this:
4740 You cannot set breakpoints or examine data in the library until after
4741 the library is loaded if the function/data symbols do not have
4744 GDB can now also read debug symbols produced by the HP C compiler on
4745 HPPAs (sorry, no C++, Fortran or 68k support).
4747 * Target byte order now dynamically selectable
4749 You can choose which byte order to use with a target system, via the
4750 commands "set endian big" and "set endian little", and you can see the
4751 current setting by using "show endian". You can also give the command
4752 "set endian auto", in which case GDB will use the byte order
4753 associated with the executable. Currently, only embedded MIPS
4754 configurations support dynamic selection of target byte order.
4756 * New DOS host serial code
4758 This version uses DPMI interrupts to handle buffered I/O, so you
4759 no longer need to run asynctsr when debugging boards connected to
4762 *** Changes in GDB-4.13:
4764 * New "complete" command
4766 This lists all the possible completions for the rest of the line, if it
4767 were to be given as a command itself. This is intended for use by emacs.
4769 * Trailing space optional in prompt
4771 "set prompt" no longer adds a space for you after the prompt you set. This
4772 allows you to set a prompt which ends in a space or one that does not.
4774 * Breakpoint hit counts
4776 "info break" now displays a count of the number of times the breakpoint
4777 has been hit. This is especially useful in conjunction with "ignore"; you
4778 can ignore a large number of breakpoint hits, look at the breakpoint info
4779 to see how many times the breakpoint was hit, then run again, ignoring one
4780 less than that number, and this will get you quickly to the last hit of
4783 * Ability to stop printing at NULL character
4785 "set print null-stop" will cause GDB to stop printing the characters of
4786 an array when the first NULL is encountered. This is useful when large
4787 arrays actually contain only short strings.
4789 * Shared library breakpoints
4791 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4792 breakpoints in shared libraries before the executable is run.
4794 * Hardware watchpoints
4796 There is a new hardware breakpoint for the watch command for sparclite
4797 targets. See gdb/sparclite/hw_breakpoint.note.
4799 Hardware watchpoints are also now supported under GNU/Linux.
4803 Annotations have been added. These are for use with graphical interfaces,
4804 and are still experimental. Currently only gdba.el uses these.
4806 * Improved Irix 5 support
4808 GDB now works properly with Irix 5.2.
4810 * Improved HPPA support
4812 GDB now works properly with the latest GCC and GAS.
4814 * New native configurations
4816 Sequent PTX4 i[34]86-sequent-ptx4
4817 HPPA running OSF/1 hppa*-*-osf*
4818 Atari TT running SVR4 m68*-*-sysv4*
4819 RS/6000 LynxOS rs6000-*-lynxos*
4823 OS/9000 i[34]86-*-os9k
4824 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4827 * Hitachi SH7000 and E7000-PC ICE support
4829 There is now support for communicating with the Hitachi E7000-PC ICE.
4830 This is available automatically when GDB is configured for the SH.
4834 As usual, a variety of small fixes and improvements, both generic
4835 and configuration-specific. See the ChangeLog for more detail.
4837 *** Changes in GDB-4.12:
4839 * Irix 5 is now supported
4843 GDB-4.12 on the HPPA has a number of changes which make it unable
4844 to debug the output from the currently released versions of GCC and
4845 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4846 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4847 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4850 *** Changes in GDB-4.11:
4852 * User visible changes:
4856 The "set remotedebug" option is now consistent between the mips remote
4857 target, remote targets using the gdb-specific protocol, UDI (AMD's
4858 debug protocol for the 29k) and the 88k bug monitor. It is now an
4859 integer specifying a debug level (normally 0 or 1, but 2 means more
4860 debugging info for the mips target).
4862 * DEC Alpha native support
4864 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4865 debug info, but GDB works fairly well with the DEC compiler and should
4866 work with a future GCC release. See the README file for a few
4867 Alpha-specific notes.
4869 * Preliminary thread implementation
4871 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4873 * LynxOS native and target support for 386
4875 This release has been hosted on LynxOS 2.2, and also can be configured
4876 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4879 * Improvements in C++ mangling/demangling.
4881 This release has much better g++ debugging, specifically in name
4882 mangling/demangling, virtual function calls, print virtual table,
4883 call methods, ...etc.
4885 *** Changes in GDB-4.10:
4887 * User visible changes:
4889 Remote debugging using the GDB-specific (`target remote') protocol now
4890 supports the `load' command. This is only useful if you have some
4891 other way of getting the stub to the target system, and you can put it
4892 somewhere in memory where it won't get clobbered by the download.
4894 Filename completion now works.
4896 When run under emacs mode, the "info line" command now causes the
4897 arrow to point to the line specified. Also, "info line" prints
4898 addresses in symbolic form (as well as hex).
4900 All vxworks based targets now support a user settable option, called
4901 vxworks-timeout. This option represents the number of seconds gdb
4902 should wait for responses to rpc's. You might want to use this if
4903 your vxworks target is, perhaps, a slow software simulator or happens
4904 to be on the far side of a thin network line.
4908 This release contains support for using a DEC alpha as a GDB host for
4909 cross debugging. Native alpha debugging is not supported yet.
4912 *** Changes in GDB-4.9:
4916 This is the first GDB release which is accompanied by a matching testsuite.
4917 The testsuite requires installation of dejagnu, which should be available
4918 via ftp from most sites that carry GNU software.
4922 'Cfront' style demangling has had its name changed to 'ARM' style, to
4923 emphasize that it was written from the specifications in the C++ Annotated
4924 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4925 disclaimers, it still generated too much confusion with users attempting to
4926 use gdb with AT&T cfront.
4930 GDB now uses a standard remote interface to a simulator library.
4931 So far, the library contains simulators for the Zilog Z8001/2, the
4932 Hitachi H8/300, H8/500 and Super-H.
4934 * New targets supported
4936 H8/300 simulator h8300-hitachi-hms or h8300hms
4937 H8/500 simulator h8500-hitachi-hms or h8500hms
4938 SH simulator sh-hitachi-hms or sh
4939 Z8000 simulator z8k-zilog-none or z8ksim
4940 IDT MIPS board over serial line mips-idt-ecoff
4942 Cross-debugging to GO32 targets is supported. It requires a custom
4943 version of the i386-stub.c module which is integrated with the
4944 GO32 memory extender.
4946 * New remote protocols
4948 MIPS remote debugging protocol.
4950 * New source languages supported
4952 This version includes preliminary support for Chill, a Pascal like language
4953 used by telecommunications companies. Chill support is also being integrated
4954 into the GNU compiler, but we don't know when it will be publically available.
4957 *** Changes in GDB-4.8:
4959 * HP Precision Architecture supported
4961 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4962 version of this support was available as a set of patches from the
4963 University of Utah. GDB does not support debugging of programs
4964 compiled with the HP compiler, because HP will not document their file
4965 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4966 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4968 Many problems in the preliminary version have been fixed.
4970 * Faster and better demangling
4972 We have improved template demangling and fixed numerous bugs in the GNU style
4973 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4974 character types (wchar_t) are now supported. Demangling of each symbol is now
4975 only done once, and is cached when the symbol table for a file is read in.
4976 This results in a small increase in memory usage for C programs, a moderate
4977 increase in memory usage for C++ programs, and a fantastic speedup in
4980 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4981 from the specifications in the Annotated Reference Manual, which AT&T's
4982 compiler does not actually implement.
4984 * G++ multiple inheritance compiler problem
4986 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4987 inheritance lattices was reworked to properly discover ambiguities. We
4988 recently found an example which causes this new algorithm to fail in a
4989 very subtle way, producing bad debug information for those classes.
4990 The file 'gcc.patch' (in this directory) can be applied to gcc to
4991 circumvent the problem. A future GCC release will contain a complete
4994 The previous G++ debug info problem (mentioned below for the gdb-4.7
4995 release) is fixed in gcc version 2.3.2.
4997 * Improved configure script
4999 The `configure' script will now attempt to guess your system type if
5000 you don't supply a host system type. The old scheme of supplying a
5001 host system triplet is preferable over using this. All the magic is
5002 done in the new `config.guess' script. Examine it for details.
5004 We have also brought our configure script much more in line with the FSF's
5005 version. It now supports the --with-xxx options. In particular,
5006 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5007 The resulting GDB will not be able to read arbitrary object file formats --
5008 only the format ``expected'' to be used on the configured target system.
5009 We hope to make this the default in a future release.
5011 * Documentation improvements
5013 There's new internal documentation on how to modify GDB, and how to
5014 produce clean changes to the code. We implore people to read it
5015 before submitting changes.
5017 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5018 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5019 `info' files are also provided. To build `info' files from scratch,
5020 you will need the latest `makeinfo' release, which will be available in
5021 a future texinfo-X.Y release.
5023 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5024 We're not sure exactly which versions have this problem, but it has
5025 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5026 or better. If that isn't possible, there is a patch in
5027 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5028 around this problem.
5032 GDB now supports array constants that can be used in expressions typed in by
5033 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5034 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5037 The new directory `gdb/sparclite' contains a program that demonstrates
5038 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5040 * New native hosts supported
5042 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5043 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5045 * New targets supported
5047 AMD 29k family via UDI a29k-amd-udi or udi29k
5049 * New file formats supported
5051 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5052 HPUX core files, and SCO 3.2v2 core files.
5056 Attaching to processes now works again; thanks for the many bug reports.
5058 We have also stomped on a bunch of core dumps caused by
5059 printf_filtered("%s") problems.
5061 We eliminated a copyright problem on the rpc and ptrace header files
5062 for VxWorks, which was discovered at the last minute during the 4.7
5063 release. You should now be able to build a VxWorks GDB.
5065 You can now interrupt gdb while an attached process is running. This
5066 will cause the attached process to stop, and give control back to GDB.
5068 We fixed problems caused by using too many file descriptors
5069 for reading symbols from object files and libraries. This was
5070 especially a problem for programs that used many (~100) shared
5073 The `step' command now only enters a subroutine if there is line number
5074 information for the subroutine. Otherwise it acts like the `next'
5075 command. Previously, `step' would enter subroutines if there was
5076 any debugging information about the routine. This avoids problems
5077 when using `cc -g1' on MIPS machines.
5079 * Internal improvements
5081 GDB's internal interfaces have been improved to make it easier to support
5082 debugging of multiple languages in the future.
5084 GDB now uses a common structure for symbol information internally.
5085 Minimal symbols (derived from linkage symbols in object files), partial
5086 symbols (from a quick scan of debug information), and full symbols
5087 contain a common subset of information, making it easier to write
5088 shared code that handles any of them.
5090 * New command line options
5092 We now accept --silent as an alias for --quiet.
5096 The memory-mapped-malloc library is now licensed under the GNU Library
5097 General Public License.
5099 *** Changes in GDB-4.7:
5101 * Host/native/target split
5103 GDB has had some major internal surgery to untangle the support for
5104 hosts and remote targets. Now, when you configure GDB for a remote
5105 target, it will no longer load in all of the support for debugging
5106 local programs on the host. When fully completed and tested, this will
5107 ensure that arbitrary host/target combinations are possible.
5109 The primary conceptual shift is to separate the non-portable code in
5110 GDB into three categories. Host specific code is required any time GDB
5111 is compiled on that host, regardless of the target. Target specific
5112 code relates to the peculiarities of the target, but can be compiled on
5113 any host. Native specific code is everything else: it can only be
5114 built when the host and target are the same system. Child process
5115 handling and core file support are two common `native' examples.
5117 GDB's use of /proc for controlling Unix child processes is now cleaner.
5118 It has been split out into a single module under the `target_ops' vector,
5119 plus two native-dependent functions for each system that uses /proc.
5121 * New hosts supported
5123 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5124 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5125 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5127 * New targets supported
5129 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5130 68030 and CPU32 m68030-*-*, m68332-*-*
5132 * New native hosts supported
5134 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5135 (386bsd is not well tested yet)
5136 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5138 * New file formats supported
5140 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5141 supports reading of `a.out.adobe' object files, which are an a.out
5142 format extended with minimal information about multiple sections.
5146 `show copying' is the same as the old `info copying'.
5147 `show warranty' is the same as `info warrantee'.
5148 These were renamed for consistency. The old commands continue to work.
5150 `info handle' is a new alias for `info signals'.
5152 You can now define pre-command hooks, which attach arbitrary command
5153 scripts to any command. The commands in the hook will be executed
5154 prior to the user's command. You can also create a hook which will be
5155 executed whenever the program stops. See gdb.texinfo.
5159 We now deal with Cfront style name mangling, and can even extract type
5160 info from mangled symbols. GDB can automatically figure out which
5161 symbol mangling style your C++ compiler uses.
5163 Calling of methods and virtual functions has been improved as well.
5167 The crash that occured when debugging Sun Ansi-C compiled binaries is
5168 fixed. This was due to mishandling of the extra N_SO stabs output
5171 We also finally got Ultrix 4.2 running in house, and fixed core file
5172 support, with help from a dozen people on the net.
5174 John M. Farrell discovered that the reason that single-stepping was so
5175 slow on all of the Mips based platforms (primarily SGI and DEC) was
5176 that we were trying to demangle and lookup a symbol used for internal
5177 purposes on every instruction that was being stepped through. Changing
5178 the name of that symbol so that it couldn't be mistaken for a C++
5179 mangled symbol sped things up a great deal.
5181 Rich Pixley sped up symbol lookups in general by getting much smarter
5182 about when C++ symbol mangling is necessary. This should make symbol
5183 completion (TAB on the command line) much faster. It's not as fast as
5184 we'd like, but it's significantly faster than gdb-4.6.
5188 A new user controllable variable 'call_scratch_address' can
5189 specify the location of a scratch area to be used when GDB
5190 calls a function in the target. This is necessary because the
5191 usual method of putting the scratch area on the stack does not work
5192 in systems that have separate instruction and data spaces.
5194 We integrated changes to support the 29k UDI (Universal Debugger
5195 Interface), but discovered at the last minute that we didn't have all
5196 of the appropriate copyright paperwork. We are working with AMD to
5197 resolve this, and hope to have it available soon.
5201 We have sped up the remote serial line protocol, especially for targets
5202 with lots of registers. It now supports a new `expedited status' ('T')
5203 message which can be used in place of the existing 'S' status message.
5204 This allows the remote stub to send only the registers that GDB
5205 needs to make a quick decision about single-stepping or conditional
5206 breakpoints, eliminating the need to fetch the entire register set for
5207 each instruction being stepped through.
5209 The GDB remote serial protocol now implements a write-through cache for
5210 registers, only re-reading the registers if the target has run.
5212 There is also a new remote serial stub for SPARC processors. You can
5213 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5214 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5215 processor with a serial port.
5219 Configure.in files have become much easier to read and modify. A new
5220 `table driven' format makes it more obvious what configurations are
5221 supported, and what files each one uses.
5225 There is a new opcodes library which will eventually contain all of the
5226 disassembly routines and opcode tables. At present, it only contains
5227 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5228 disassembler (binutils/objdump) to share these routines.
5230 The libiberty library is now copylefted under the GNU Library General
5231 Public License. This allows more liberal use, and was done so libg++
5232 can use it. This makes no difference to GDB, since the Library License
5233 grants all the rights from the General Public License.
5237 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5238 reference to the stabs symbol info used by the debugger. It is (as far
5239 as we know) the only published document on this fascinating topic. We
5240 encourage you to read it, compare it to the stabs information on your
5241 system, and send improvements on the document in general (to
5244 And, of course, many bugs have been fixed.
5247 *** Changes in GDB-4.6:
5249 * Better support for C++ function names
5251 GDB now accepts as input the "demangled form" of C++ overloaded function
5252 names and member function names, and can do command completion on such names
5253 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5254 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5255 Make use of command completion, it is your friend.
5257 GDB also now accepts a variety of C++ mangled symbol formats. They are
5258 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5259 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5260 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5261 for the list of formats.
5263 * G++ symbol mangling problem
5265 Recent versions of gcc have a bug in how they emit debugging information for
5266 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5267 directory) can be applied to gcc to fix the problem. Alternatively, if you
5268 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5269 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5270 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5273 * New 'maintenance' command
5275 All of the commands related to hacking GDB internals have been moved out of
5276 the main command set, and now live behind the 'maintenance' command. This
5277 can also be abbreviated as 'mt'. The following changes were made:
5279 dump-me -> maintenance dump-me
5280 info all-breakpoints -> maintenance info breakpoints
5281 printmsyms -> maintenance print msyms
5282 printobjfiles -> maintenance print objfiles
5283 printpsyms -> maintenance print psymbols
5284 printsyms -> maintenance print symbols
5286 The following commands are new:
5288 maintenance demangle Call internal GDB demangler routine to
5289 demangle a C++ link name and prints the result.
5290 maintenance print type Print a type chain for a given symbol
5292 * Change to .gdbinit file processing
5294 We now read the $HOME/.gdbinit file before processing the argv arguments
5295 (e.g. reading symbol files or core files). This allows global parameters to
5296 be set, which will apply during the symbol reading. The ./.gdbinit is still
5297 read after argv processing.
5299 * New hosts supported
5301 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5303 GNU/Linux support i386-unknown-linux or linux
5305 We are also including code to support the HP/PA running BSD and HPUX. This
5306 is almost guaranteed not to work, as we didn't have time to test or build it
5307 for this release. We are including it so that the more adventurous (or
5308 masochistic) of you can play with it. We also had major problems with the
5309 fact that the compiler that we got from HP doesn't support the -g option.
5312 * New targets supported
5314 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5316 * More smarts about finding #include files
5318 GDB now remembers the compilation directory for all include files, and for
5319 all files from which C is generated (like yacc and lex sources). This
5320 greatly improves GDB's ability to find yacc/lex sources, and include files,
5321 especially if you are debugging your program from a directory different from
5322 the one that contains your sources.
5324 We also fixed a bug which caused difficulty with listing and setting
5325 breakpoints in include files which contain C code. (In the past, you had to
5326 try twice in order to list an include file that you hadn't looked at before.)
5328 * Interesting infernals change
5330 GDB now deals with arbitrary numbers of sections, where the symbols for each
5331 section must be relocated relative to that section's landing place in the
5332 target's address space. This work was needed to support ELF with embedded
5333 stabs used by Solaris-2.0.
5335 * Bug fixes (of course!)
5337 There have been loads of fixes for the following things:
5338 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5339 i960, stabs, DOS(GO32), procfs, etc...
5341 See the ChangeLog for details.
5343 *** Changes in GDB-4.5:
5345 * New machines supported (host and target)
5347 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5349 SGI Irix-4.x mips-sgi-irix4 or iris4
5351 * New malloc package
5353 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5354 Mmalloc is capable of handling mutiple heaps of memory. It is also
5355 capable of saving a heap to a file, and then mapping it back in later.
5356 This can be used to greatly speedup the startup of GDB by using a
5357 pre-parsed symbol table which lives in a mmalloc managed heap. For
5358 more details, please read mmalloc/mmalloc.texi.
5362 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5363 'help info proc' for details.
5365 * MIPS ecoff symbol table format
5367 The code that reads MIPS symbol table format is now supported on all hosts.
5368 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5371 * File name changes for MS-DOS
5373 Many files in the config directories have been renamed to make it easier to
5374 support GDB on MS-DOSe systems (which have very restrictive file name
5375 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5376 environment) is close to working but has some remaining problems. Note
5377 that debugging of DOS programs is not supported, due to limitations
5378 in the ``operating system'', but it can be used to host cross-debugging.
5380 * Cross byte order fixes
5382 Many fixes have been made to support cross debugging of Sparc and MIPS
5383 targets from hosts whose byte order differs.
5385 * New -mapped and -readnow options
5387 If memory-mapped files are available on your system through the 'mmap'
5388 system call, you can use the -mapped option on the `file' or
5389 `symbol-file' commands to cause GDB to write the symbols from your
5390 program into a reusable file. If the program you are debugging is
5391 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5392 Future GDB debugging sessions will notice the presence of this file,
5393 and will quickly map in symbol information from it, rather than reading
5394 the symbol table from the executable program. Using the '-mapped'
5395 option in a GDB `file' or `symbol-file' command has the same effect as
5396 starting GDB with the '-mapped' command-line option.
5398 You can cause GDB to read the entire symbol table immediately by using
5399 the '-readnow' option with any of the commands that load symbol table
5400 information (or on the GDB command line). This makes the command
5401 slower, but makes future operations faster.
5403 The -mapped and -readnow options are typically combined in order to
5404 build a `fred.syms' file that contains complete symbol information.
5405 A simple GDB invocation to do nothing but build a `.syms' file for future
5408 gdb -batch -nx -mapped -readnow programname
5410 The `.syms' file is specific to the host machine on which GDB is run.
5411 It holds an exact image of GDB's internal symbol table. It cannot be
5412 shared across multiple host platforms.
5414 * longjmp() handling
5416 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5417 siglongjmp() without losing control. This feature has not yet been ported to
5418 all systems. It currently works on many 386 platforms, all MIPS-based
5419 platforms (SGI, DECstation, etc), and Sun3/4.
5423 Preliminary work has been put in to support the new Solaris OS from Sun. At
5424 this time, it can control and debug processes, but it is not capable of
5429 As always, many many bug fixes. The major areas were with g++, and mipsread.
5430 People using the MIPS-based platforms should experience fewer mysterious
5431 crashes and trashed symbol tables.
5433 *** Changes in GDB-4.4:
5435 * New machines supported (host and target)
5437 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5439 BSD Reno on Vax vax-dec-bsd
5440 Ultrix on Vax vax-dec-ultrix
5442 * New machines supported (target)
5444 AMD 29000 embedded, using EBMON a29k-none-none
5448 GDB continues to improve its handling of C++. `References' work better.
5449 The demangler has also been improved, and now deals with symbols mangled as
5450 per the Annotated C++ Reference Guide.
5452 GDB also now handles `stabs' symbol information embedded in MIPS
5453 `ecoff' symbol tables. Since the ecoff format was not easily
5454 extensible to handle new languages such as C++, this appeared to be a
5455 good way to put C++ debugging info into MIPS binaries. This option
5456 will be supported in the GNU C compiler, version 2, when it is
5459 * New features for SVR4
5461 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5462 shared libraries. Debugging dynamically linked programs should present
5463 only minor differences from debugging statically linked programs.
5465 The `info proc' command will print out information about any process
5466 on an SVR4 system (including the one you are debugging). At the moment,
5467 it prints the address mappings of the process.
5469 If you bring up GDB on another SVR4 system, please send mail to
5472 * Better dynamic linking support in SunOS
5474 Reading symbols from shared libraries which contain debugging symbols
5475 now works properly. However, there remain issues such as automatic
5476 skipping of `transfer vector' code during function calls, which
5477 make it harder to debug code in a shared library, than to debug the
5478 same code linked statically.
5482 GDB is now using the latest `getopt' routines from the FSF. This
5483 version accepts the -- prefix for options with long names. GDB will
5484 continue to accept the old forms (-option and +option) as well.
5485 Various single letter abbreviations for options have been explicity
5486 added to the option table so that they won't get overshadowed in the
5487 future by other options that begin with the same letter.
5491 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5492 Many assorted bugs have been handled. Many more remain to be handled.
5493 See the various ChangeLog files (primarily in gdb and bfd) for details.
5496 *** Changes in GDB-4.3:
5498 * New machines supported (host and target)
5500 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5501 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5502 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5504 * Almost SCO Unix support
5506 We had hoped to support:
5507 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5508 (except for core file support), but we discovered very late in the release
5509 that it has problems with process groups that render gdb unusable. Sorry
5510 about that. I encourage people to fix it and post the fixes.
5512 * Preliminary ELF and DWARF support
5514 GDB can read ELF object files on System V Release 4, and can handle
5515 debugging records for C, in DWARF format, in ELF files. This support
5516 is preliminary. If you bring up GDB on another SVR4 system, please
5522 GDB now uses the latest `readline' library. One user-visible change
5523 is that two tabs will list possible command completions, which previously
5524 required typing M-? (meta-question mark, or ESC ?).
5528 The `stepi' bug that many of you noticed has been squashed.
5529 Many bugs in C++ have been handled. Many more remain to be handled.
5530 See the various ChangeLog files (primarily in gdb and bfd) for details.
5532 * State of the MIPS world (in case you wondered):
5534 GDB can understand the symbol tables emitted by the compilers
5535 supplied by most vendors of MIPS-based machines, including DEC. These
5536 symbol tables are in a format that essentially nobody else uses.
5538 Some versions of gcc come with an assembler post-processor called
5539 mips-tfile. This program is required if you want to do source-level
5540 debugging of gcc-compiled programs. I believe FSF does not ship
5541 mips-tfile with gcc version 1, but it will eventually come with gcc
5544 Debugging of g++ output remains a problem. g++ version 1.xx does not
5545 really support it at all. (If you're lucky, you should be able to get
5546 line numbers and stack traces to work, but no parameters or local
5547 variables.) With some work it should be possible to improve the
5550 When gcc version 2 is released, you will have somewhat better luck.
5551 However, even then you will get confusing results for inheritance and
5554 We will eventually provide full debugging of g++ output on
5555 DECstations. This will probably involve some kind of stabs-in-ecoff
5556 encapulation, but the details have not been worked out yet.
5559 *** Changes in GDB-4.2:
5561 * Improved configuration
5563 Only one copy of `configure' exists now, and it is not self-modifying.
5564 Porting BFD is simpler.
5568 The `step' and `next' commands now only stop at the first instruction
5569 of a source line. This prevents the multiple stops that used to occur
5570 in switch statements, for-loops, etc. `Step' continues to stop if a
5571 function that has debugging information is called within the line.
5575 Lots of small bugs fixed. More remain.
5577 * New host supported (not target)
5579 Intel 386 PC clone running Mach i386-none-mach
5582 *** Changes in GDB-4.1:
5584 * Multiple source language support
5586 GDB now has internal scaffolding to handle several source languages.
5587 It determines the type of each source file from its filename extension,
5588 and will switch expression parsing and number formatting to match the
5589 language of the function in the currently selected stack frame.
5590 You can also specifically set the language to be used, with
5591 `set language c' or `set language modula-2'.
5595 GDB now has preliminary support for the GNU Modula-2 compiler,
5596 currently under development at the State University of New York at
5597 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5598 continue through the fall of 1991 and into 1992.
5600 Other Modula-2 compilers are currently not supported, and attempting to
5601 debug programs compiled with them will likely result in an error as the
5602 symbol table is read. Feel free to work on it, though!
5604 There are hooks in GDB for strict type checking and range checking,
5605 in the `Modula-2 philosophy', but they do not currently work.
5609 GDB can now write to executable and core files (e.g. patch
5610 a variable's value). You must turn this switch on, specify
5611 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5612 by assigning a new value to a variable. Modifications take
5615 * Automatic SunOS shared library reading
5617 When you run your program, GDB automatically determines where its
5618 shared libraries (if any) have been loaded, and reads their symbols.
5619 The `share' command is no longer needed. This also works when
5620 examining core files.
5624 You can specify the number of lines that the `list' command shows.
5627 * New machines supported (host and target)
5629 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5630 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5631 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5633 * New hosts supported (not targets)
5635 IBM RT/PC: romp-ibm-aix or rtpc
5637 * New targets supported (not hosts)
5639 AMD 29000 embedded with COFF a29k-none-coff
5640 AMD 29000 embedded with a.out a29k-none-aout
5641 Ultracomputer remote kernel debug a29k-nyu-kern
5643 * New remote interfaces
5649 *** Changes in GDB-4.0:
5653 Wide output is wrapped at good places to make the output more readable.
5655 Gdb now supports cross-debugging from a host machine of one type to a
5656 target machine of another type. Communication with the target system
5657 is over serial lines. The ``target'' command handles connecting to the
5658 remote system; the ``load'' command will download a program into the
5659 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5660 also supports debugging of realtime processes running under VxWorks,
5661 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5662 stub on the target system.
5664 New CPUs supported include the AMD 29000 and Intel 960.
5666 GDB now reads object files and symbol tables via a ``binary file''
5667 library, which allows a single copy of GDB to debug programs of multiple
5668 object file types such as a.out and coff.
5670 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5671 refcard.dvi and refcard.ps are available to format it).
5674 * Control-Variable user interface simplified
5676 All variables that control the operation of the debugger can be set
5677 by the ``set'' command, and displayed by the ``show'' command.
5679 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5680 ``Show prompt'' produces the response:
5681 Gdb's prompt is new-gdb=>.
5683 What follows are the NEW set commands. The command ``help set'' will
5684 print a complete list of old and new set commands. ``help set FOO''
5685 will give a longer description of the variable FOO. ``show'' will show
5686 all of the variable descriptions and their current settings.
5688 confirm on/off: Enables warning questions for operations that are
5689 hard to recover from, e.g. rerunning the program while
5690 it is already running. Default is ON.
5692 editing on/off: Enables EMACS style command line editing
5693 of input. Previous lines can be recalled with
5694 control-P, the current line can be edited with control-B,
5695 you can search for commands with control-R, etc.
5698 history filename NAME: NAME is where the gdb command history
5699 will be stored. The default is .gdb_history,
5700 or the value of the environment variable
5703 history size N: The size, in commands, of the command history. The
5704 default is 256, or the value of the environment variable
5707 history save on/off: If this value is set to ON, the history file will
5708 be saved after exiting gdb. If set to OFF, the
5709 file will not be saved. The default is OFF.
5711 history expansion on/off: If this value is set to ON, then csh-like
5712 history expansion will be performed on
5713 command line input. The default is OFF.
5715 radix N: Sets the default radix for input and output. It can be set
5716 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5717 in the current radix, so "set radix 10" is always a no-op.
5719 height N: This integer value is the number of lines on a page. Default
5720 is 24, the current `stty rows'' setting, or the ``li#''
5721 setting from the termcap entry matching the environment
5724 width N: This integer value is the number of characters on a line.
5725 Default is 80, the current `stty cols'' setting, or the ``co#''
5726 setting from the termcap entry matching the environment
5729 Note: ``set screensize'' is obsolete. Use ``set height'' and
5730 ``set width'' instead.
5732 print address on/off: Print memory addresses in various command displays,
5733 such as stack traces and structure values. Gdb looks
5734 more ``symbolic'' if you turn this off; it looks more
5735 ``machine level'' with it on. Default is ON.
5737 print array on/off: Prettyprint arrays. New convenient format! Default
5740 print demangle on/off: Print C++ symbols in "source" form if on,
5743 print asm-demangle on/off: Same, for assembler level printouts
5746 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5749 * Support for Epoch Environment.
5751 The epoch environment is a version of Emacs v18 with windowing. One
5752 new command, ``inspect'', is identical to ``print'', except that if you
5753 are running in the epoch environment, the value is printed in its own
5757 * Support for Shared Libraries
5759 GDB can now debug programs and core files that use SunOS shared libraries.
5760 Symbols from a shared library cannot be referenced
5761 before the shared library has been linked with the program (this
5762 happens after you type ``run'' and before the function main() is entered).
5763 At any time after this linking (including when examining core files
5764 from dynamically linked programs), gdb reads the symbols from each
5765 shared library when you type the ``sharedlibrary'' command.
5766 It can be abbreviated ``share''.
5768 sharedlibrary REGEXP: Load shared object library symbols for files
5769 matching a unix regular expression. No argument
5770 indicates to load symbols for all shared libraries.
5772 info sharedlibrary: Status of loaded shared libraries.
5777 A watchpoint stops execution of a program whenever the value of an
5778 expression changes. Checking for this slows down execution
5779 tremendously whenever you are in the scope of the expression, but is
5780 quite useful for catching tough ``bit-spreader'' or pointer misuse
5781 problems. Some machines such as the 386 have hardware for doing this
5782 more quickly, and future versions of gdb will use this hardware.
5784 watch EXP: Set a watchpoint (breakpoint) for an expression.
5786 info watchpoints: Information about your watchpoints.
5788 delete N: Deletes watchpoint number N (same as breakpoints).
5789 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5790 enable N: Re-enables watchpoint number N (same as breakpoints).
5793 * C++ multiple inheritance
5795 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5798 * C++ exception handling
5800 Gdb now supports limited C++ exception handling. Besides the existing
5801 ability to breakpoint on an exception handler, gdb can breakpoint on
5802 the raising of an exception (before the stack is peeled back to the
5805 catch FOO: If there is a FOO exception handler in the dynamic scope,
5806 set a breakpoint to catch exceptions which may be raised there.
5807 Multiple exceptions (``catch foo bar baz'') may be caught.
5809 info catch: Lists all exceptions which may be caught in the
5810 current stack frame.
5813 * Minor command changes
5815 The command ``call func (arg, arg, ...)'' now acts like the print
5816 command, except it does not print or save a value if the function's result
5817 is void. This is similar to dbx usage.
5819 The ``up'' and ``down'' commands now always print the frame they end up
5820 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5821 frames without printing.
5823 * New directory command
5825 'dir' now adds directories to the FRONT of the source search path.
5826 The path starts off empty. Source files that contain debug information
5827 about the directory in which they were compiled can be found even
5828 with an empty path; Sun CC and GCC include this information. If GDB can't
5829 find your source file in the current directory, type "dir .".
5831 * Configuring GDB for compilation
5833 For normal use, type ``./configure host''. See README or gdb.texinfo
5836 GDB now handles cross debugging. If you are remotely debugging between
5837 two different machines, type ``./configure host -target=targ''.
5838 Host is the machine where GDB will run; targ is the machine
5839 where the program that you are debugging will run.