1 What has changed in GDB?
2 (Organized release by release)
6 New events which are triggered when GDB modifies the state of the
9 ** gdb.events.inferior_call_pre: Function call is about to be made.
10 ** gdb.events.inferior_call_post: Function call has just been made.
11 ** gdb.events.memory_changed: A memory location has been altered.
12 ** gdb.events.register_changed: A register has been altered.
14 *** Changes since GDB 7.8
16 * GDB now supports hardware watchpoints on x86 GNU Hurd.
20 ** You can now access frame registers from Python scripts.
21 ** New attribute 'producer' for gdb.Symtab objects.
22 ** gdb.Objfile objects have a new attribute "progspace",
23 which is the gdb.Progspace object of the containing program space.
24 ** gdb.Objfile objects have a new attribute "owner".
25 ** gdb.Objfile objects have a new attribute "build_id",
26 which is the build ID generated when the file was built.
27 ** gdb.Objfile objects have a new method "add_separate_debug_file".
28 ** A new event "gdb.clear_objfiles" has been added, triggered when
29 selecting a new file to debug.
30 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
32 * New Python-based convenience functions:
34 ** $_caller_is(name [, number_of_frames])
35 ** $_caller_matches(regexp [, number_of_frames])
36 ** $_any_caller_is(name [, number_of_frames])
37 ** $_any_caller_matches(regexp [, number_of_frames])
41 queue-signal signal-name-or-number
42 Queue a signal to be delivered to the thread when it is resumed.
44 add-auto-load-scripts-directory directory
45 Add entries to the list of directories from which to load auto-loaded
48 maint print user-registers
49 List all currently available "user" registers.
51 * On resume, GDB now always passes the signal the program had stopped
52 for to the thread the signal was sent to, even if the user changed
53 threads before resuming. Previously GDB would often (but not
54 always) deliver the signal to the thread that happens to be current
57 * Conversely, the "signal" command now consistently delivers the
58 requested signal to the current thread. GDB now asks for
59 confirmation if the program had stopped for a signal and the user
60 switched threads meanwhile.
62 * "breakpoint always-inserted" modes "off" and "auto" merged.
64 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
65 won't remove breakpoints from the target until all threads stop,
66 even in non-stop mode. The "auto" mode has been removed, and "off"
67 is now the default mode.
71 ** The -list-thread-groups command outputs an exit-code field for
72 inferiors that have exited.
76 Support for these obsolete configurations has been removed.
78 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
79 SGI Irix-5.x mips-*-irix5*
80 SGI Irix-6.x mips-*-irix6*
81 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
82 VAX running Ultrix vax-*-ultrix*
84 *** Changes in GDB 7.8
86 * New command line options
89 This is an alias for the --data-directory option.
91 * GDB supports printing and modifying of variable length automatic arrays
92 as specified in ISO C99.
94 * The ARM simulator now supports instruction level tracing
95 with or without disassembly.
99 GDB now has support for scripting using Guile. Whether this is
100 available is determined at configure time.
101 Guile version 2.0 or greater is required.
102 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
104 * New commands (for set/show, see "New options" below)
108 Invoke CODE by passing it to the Guile interpreter.
112 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
114 info auto-load guile-scripts [regexp]
115 Print the list of automatically loaded Guile scripts.
117 * The source command is now capable of sourcing Guile scripts.
118 This feature is dependent on the debugger being built with Guile support.
122 set print symbol-loading (off|brief|full)
123 show print symbol-loading
124 Control whether to print informational messages when loading symbol
125 information for a file. The default is "full", but when debugging
126 programs with large numbers of shared libraries the amount of output
129 set guile print-stack (none|message|full)
130 show guile print-stack
131 Show a stack trace when an error is encountered in a Guile script.
133 set auto-load guile-scripts (on|off)
134 show auto-load guile-scripts
135 Control auto-loading of Guile script files.
137 maint ada set ignore-descriptive-types (on|off)
138 maint ada show ignore-descriptive-types
139 Control whether the debugger should ignore descriptive types in Ada
140 programs. The default is not to ignore the descriptive types. See
141 the user manual for more details on descriptive types and the intended
142 usage of this option.
144 set auto-connect-native-target
146 Control whether GDB is allowed to automatically connect to the
147 native target for the run, attach, etc. commands when not connected
148 to any target yet. See also "target native" below.
150 set record btrace replay-memory-access (read-only|read-write)
151 show record btrace replay-memory-access
152 Control what memory accesses are allowed during replay.
154 maint set target-async (on|off)
155 maint show target-async
156 This controls whether GDB targets operate in synchronous or
157 asynchronous mode. Normally the default is asynchronous, if it is
158 available; but this can be changed to more easily debug problems
159 occurring only in synchronous mode.
161 set mi-async (on|off)
163 Control whether MI asynchronous mode is preferred. This supersedes
164 "set target-async" of previous GDB versions.
166 * "set target-async" is deprecated as a CLI option and is now an alias
167 for "set mi-async" (only puts MI into async mode).
169 * Background execution commands (e.g., "c&", "s&", etc.) are now
170 possible ``out of the box'' if the target supports them. Previously
171 the user would need to explicitly enable the possibility with the
172 "set target-async on" command.
174 * New features in the GDB remote stub, GDBserver
176 ** New option --debug-format=option1[,option2,...] allows one to add
177 additional text to each output. At present only timestamps
178 are supported: --debug-format=timestamps.
179 Timestamps can also be turned on with the
180 "monitor set debug-format timestamps" command from GDB.
182 * The 'record instruction-history' command now starts counting instructions
183 at one. This also affects the instruction ranges reported by the
184 'record function-call-history' command when given the /i modifier.
186 * The command 'record function-call-history' supports a new modifier '/c' to
187 indent the function names based on their call stack depth.
188 The fields for the '/i' and '/l' modifier have been reordered.
189 The source line range is now prefixed with 'at'.
190 The instruction range is now prefixed with 'inst'.
191 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
192 "record instruction-history" and "list" commands.
194 * The ranges given as arguments to the 'record function-call-history' and
195 'record instruction-history' commands are now inclusive.
197 * The btrace record target now supports the 'record goto' command.
198 For locations inside the execution trace, the back trace is computed
199 based on the information stored in the execution trace.
201 * The btrace record target supports limited reverse execution and replay.
202 The target does not record data and therefore does not allow reading
205 * The "catch syscall" command now works on s390*-linux* targets.
207 * The "compare-sections" command is no longer specific to target
208 remote. It now works with all targets.
210 * All native targets are now consistently called "native".
211 Consequently, the "target child", "target GNU", "target djgpp",
212 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
213 commands have been replaced with "target native". The QNX/NTO port
214 leaves the "procfs" target in place and adds a "native" target for
215 consistency with other ports. The impact on users should be minimal
216 as these commands previously either throwed an error, or were
217 no-ops. The target's name is visible in the output of the following
218 commands: "help target", "info target", "info files", "maint print
221 * The "target native" command now connects to the native target. This
222 can be used to launch native programs even when "set
223 auto-connect-native-target" is set to off.
225 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
227 * Support for Intel(R) AVX-512 registers on GNU/Linux.
228 Support displaying and modifying Intel(R) AVX-512 registers
229 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
233 qXfer:btrace:read's annex
234 The qXfer:btrace:read packet supports a new annex 'delta' to read
235 branch trace incrementally.
239 ** Valid Python operations on gdb.Value objects representing
240 structs/classes invoke the corresponding overloaded operators if
242 ** New `Xmethods' feature in the Python API. Xmethods are
243 additional methods or replacements for existing methods of a C++
244 class. This feature is useful for those cases where a method
245 defined in C++ source code could be inlined or optimized out by
246 the compiler, making it unavailable to GDB.
249 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
251 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
252 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
253 its alias "share", instead.
255 * The commands "set remotebaud" and "show remotebaud" are no longer
256 supported. Use "set serial baud" and "show serial baud" (respectively)
261 ** A new option "-gdb-set mi-async" replaces "-gdb-set
262 target-async". The latter is left as a deprecated alias of the
263 former for backward compatibility. If the target supports it,
264 CLI background execution commands are now always possible by
265 default, independently of whether the frontend stated a
266 preference for asynchronous execution with "-gdb-set mi-async".
267 Previously "-gdb-set target-async off" affected both MI execution
268 commands and CLI execution commands.
270 *** Changes in GDB 7.7
272 * Improved support for process record-replay and reverse debugging on
273 arm*-linux* targets. Support for thumb32 and syscall instruction
274 recording has been added.
276 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
278 * GDB now supports Fission DWP file format version 2.
279 http://gcc.gnu.org/wiki/DebugFission
281 * New convenience function "$_isvoid", to check whether an expression
282 is void. A void expression is an expression where the type of the
283 result is "void". For example, some convenience variables may be
284 "void" when evaluated (e.g., "$_exitcode" before the execution of
285 the program being debugged; or an undefined convenience variable).
286 Another example, when calling a function whose return type is
289 * The "maintenance print objfiles" command now takes an optional regexp.
291 * The "catch syscall" command now works on arm*-linux* targets.
293 * GDB now consistently shows "<not saved>" when printing values of
294 registers the debug info indicates have not been saved in the frame
295 and there's nowhere to retrieve them from
296 (callee-saved/call-clobbered registers):
301 (gdb) info registers rax
304 Before, the former would print "<optimized out>", and the latter
305 "*value not available*".
307 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
312 ** Frame filters and frame decorators have been added.
313 ** Temporary breakpoints are now supported.
314 ** Line tables representation has been added.
315 ** New attribute 'parent_type' for gdb.Field objects.
316 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
317 ** New attribute 'name' for gdb.Type objects.
321 Nios II ELF nios2*-*-elf
322 Nios II GNU/Linux nios2*-*-linux
323 Texas Instruments MSP430 msp430*-*-elf
325 * Removed native configurations
327 Support for these a.out NetBSD and OpenBSD obsolete configurations has
328 been removed. ELF variants of these configurations are kept supported.
330 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
331 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
332 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
333 i[34567]86-*-openbsd3.[0-3]
334 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
335 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
336 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
340 Like "catch throw", but catches a re-thrown exception.
342 Renamed from old "maint check-symtabs".
344 Perform consistency checks on symtabs.
346 Expand symtabs matching an optional regexp.
349 Display the details of GDB configure-time options.
351 maint set|show per-command
352 maint set|show per-command space
353 maint set|show per-command time
354 maint set|show per-command symtab
355 Enable display of per-command gdb resource usage.
357 remove-symbol-file FILENAME
358 remove-symbol-file -a ADDRESS
359 Remove a symbol file added via add-symbol-file. The file to remove
360 can be identified by its filename or by an address that lies within
361 the boundaries of this symbol file in memory.
364 info exceptions REGEXP
365 Display the list of Ada exceptions defined in the program being
366 debugged. If provided, only the exceptions whose names match REGEXP
371 set debug symfile off|on
373 Control display of debugging info regarding reading symbol files and
374 symbol tables within those files
376 set print raw frame-arguments
377 show print raw frame-arguments
378 Set/show whether to print frame arguments in raw mode,
379 disregarding any defined pretty-printers.
381 set remote trace-status-packet
382 show remote trace-status-packet
383 Set/show the use of remote protocol qTStatus packet.
387 Control display of debugging messages related to Nios II targets.
391 Control whether target-assisted range stepping is enabled.
393 set startup-with-shell
394 show startup-with-shell
395 Specifies whether Unix child processes are started via a shell or
400 Use the target memory cache for accesses to the code segment. This
401 improves performance of remote debugging (particularly disassembly).
403 * You can now use a literal value 'unlimited' for options that
404 interpret 0 or -1 as meaning "unlimited". E.g., "set
405 trace-buffer-size unlimited" is now an alias for "set
406 trace-buffer-size -1" and "set height unlimited" is now an alias for
409 * The "set debug symtab-create" debugging option of GDB has been changed to
410 accept a verbosity level. 0 means "off", 1 provides basic debugging
411 output, and values of 2 or greater provides more verbose output.
413 * New command-line options
415 Display the details of GDB configure-time options.
417 * The command 'tsave' can now support new option '-ctf' to save trace
418 buffer in Common Trace Format.
420 * Newly installed $prefix/bin/gcore acts as a shell interface for the
423 * GDB now implements the the C++ 'typeid' operator.
425 * The new convenience variable $_exception holds the exception being
426 thrown or caught at an exception-related catchpoint.
428 * The exception-related catchpoints, like "catch throw", now accept a
429 regular expression which can be used to filter exceptions by type.
431 * The new convenience variable $_exitsignal is automatically set to
432 the terminating signal number when the program being debugged dies
433 due to an uncaught signal.
437 ** All MI commands now accept an optional "--language" option.
438 Support for this feature can be verified by using the "-list-features"
439 command, which should contain "language-option".
441 ** The new command -info-gdb-mi-command allows the user to determine
442 whether a GDB/MI command is supported or not.
444 ** The "^error" result record returned when trying to execute an undefined
445 GDB/MI command now provides a variable named "code" whose content is the
446 "undefined-command" error code. Support for this feature can be verified
447 by using the "-list-features" command, which should contain
448 "undefined-command-error-code".
450 ** The -trace-save MI command can optionally save trace buffer in Common
453 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
455 ** The command -data-list-register-values now accepts an optional
456 "--skip-unavailable" option. When used, only the available registers
459 ** The new command -trace-frame-collected dumps collected variables,
460 computed expressions, tvars, memory and registers in a traceframe.
462 ** The commands -stack-list-locals, -stack-list-arguments and
463 -stack-list-variables now accept an option "--skip-unavailable".
464 When used, only the available locals or arguments are displayed.
466 ** The -exec-run command now accepts an optional "--start" option.
467 When used, the command follows the same semantics as the "start"
468 command, stopping the program's execution at the start of its
469 main subprogram. Support for this feature can be verified using
470 the "-list-features" command, which should contain
471 "exec-run-start-option".
473 ** The new commands -catch-assert and -catch-exceptions insert
474 catchpoints stopping the program when Ada exceptions are raised.
476 ** The new command -info-ada-exceptions provides the equivalent of
477 the new "info exceptions" command.
479 * New system-wide configuration scripts
480 A GDB installation now provides scripts suitable for use as system-wide
481 configuration scripts for the following systems:
485 * GDB now supports target-assigned range stepping with remote targets.
486 This improves the performance of stepping source lines by reducing
487 the number of control packets from/to GDB. See "New remote packets"
490 * GDB now understands the element 'tvar' in the XML traceframe info.
491 It has the id of the collected trace state variables.
493 * On S/390 targets that provide the transactional-execution feature,
494 the program interruption transaction diagnostic block (TDB) is now
495 represented as a number of additional "registers" in GDB.
501 The vCont packet supports a new 'r' action, that tells the remote
502 stub to step through an address range itself, without GDB
503 involvemement at each single-step.
505 qXfer:libraries-svr4:read's annex
506 The previously unused annex of the qXfer:libraries-svr4:read packet
507 is now used to support passing an argument list. The remote stub
508 reports support for this argument list to GDB's qSupported query.
509 The defined arguments are "start" and "prev", used to reduce work
510 necessary for library list updating, resulting in significant
513 * New features in the GDB remote stub, GDBserver
515 ** GDBserver now supports target-assisted range stepping. Currently
516 enabled on x86/x86_64 GNU/Linux targets.
518 ** GDBserver now adds element 'tvar' in the XML in the reply to
519 'qXfer:traceframe-info:read'. It has the id of the collected
520 trace state variables.
522 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
525 * New 'z' formatter for printing and examining memory, this displays the
526 value as hexadecimal zero padded on the left to the size of the type.
528 * GDB can now use Windows x64 unwinding data.
530 * The "set remotebaud" command has been replaced by "set serial baud".
531 Similarly, "show remotebaud" has been replaced by "show serial baud".
532 The "set remotebaud" and "show remotebaud" commands are still available
533 to provide backward compatibility with older versions of GDB.
535 *** Changes in GDB 7.6
537 * Target record has been renamed to record-full.
538 Record/replay is now enabled with the "record full" command.
539 This also affects settings that are associated with full record/replay
540 that have been moved from "set/show record" to "set/show record full":
542 set|show record full insn-number-max
543 set|show record full stop-at-limit
544 set|show record full memory-query
546 * A new record target "record-btrace" has been added. The new target
547 uses hardware support to record the control-flow of a process. It
548 does not support replaying the execution, but it implements the
549 below new commands for investigating the recorded execution log.
550 This new recording method can be enabled using:
554 The "record-btrace" target is only available on Intel Atom processors
555 and requires a Linux kernel 2.6.32 or later.
557 * Two new commands have been added for record/replay to give information
558 about the recorded execution without having to replay the execution.
559 The commands are only supported by "record btrace".
561 record instruction-history prints the execution history at
562 instruction granularity
564 record function-call-history prints the execution history at
567 * New native configurations
569 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
570 FreeBSD/powerpc powerpc*-*-freebsd
571 x86_64/Cygwin x86_64-*-cygwin*
572 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
576 ARM AArch64 aarch64*-*-elf
577 ARM AArch64 GNU/Linux aarch64*-*-linux
578 Lynx 178 PowerPC powerpc-*-lynx*178
579 x86_64/Cygwin x86_64-*-cygwin*
580 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
582 * If the configured location of system.gdbinit file (as given by the
583 --with-system-gdbinit option at configure time) is in the
584 data-directory (as specified by --with-gdb-datadir at configure
585 time) or in one of its subdirectories, then GDB will look for the
586 system-wide init file in the directory specified by the
587 --data-directory command-line option.
589 * New command line options:
591 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
592 other initialization files, unlike -nx which disables all of them.
594 * Removed command line options
596 -epoch This was used by the gdb mode in Epoch, an ancient fork of
599 * The 'ptype' and 'whatis' commands now accept an argument to control
602 * 'info proc' now works on some core files.
606 ** Vectors can be created with gdb.Type.vector.
608 ** Python's atexit.register now works in GDB.
610 ** Types can be pretty-printed via a Python API.
612 ** Python 3 is now supported (in addition to Python 2.4 or later)
614 ** New class gdb.Architecture exposes GDB's internal representation
615 of architecture in the Python API.
617 ** New method Frame.architecture returns the gdb.Architecture object
618 corresponding to the frame's architecture.
620 * New Python-based convenience functions:
622 ** $_memeq(buf1, buf2, length)
623 ** $_streq(str1, str2)
625 ** $_regex(str, regex)
627 * The 'cd' command now defaults to using '~' (the home directory) if not
630 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
631 default for GCC since November 2000.
633 * The command 'forward-search' can now be abbreviated as 'fo'.
635 * The command 'info tracepoints' can now display 'installed on target'
636 or 'not installed on target' for each non-pending location of tracepoint.
638 * New configure options
640 --enable-libmcheck/--disable-libmcheck
641 By default, development versions are built with -lmcheck on hosts
642 that support it, in order to help track memory corruption issues.
643 Release versions, on the other hand, are built without -lmcheck
644 by default. The --enable-libmcheck/--disable-libmcheck configure
645 options allow the user to override that default.
646 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
647 This configure option allows the user to build GDB with
648 libbabeltrace using which GDB can read Common Trace Format data.
650 * New commands (for set/show, see "New options" below)
653 Catch signals. This is similar to "handle", but allows commands and
654 conditions to be attached.
657 List the BFDs known to GDB.
659 python-interactive [command]
661 Start a Python interactive prompt, or evaluate the optional command
662 and print the result of expressions.
665 "py" is a new alias for "python".
667 enable type-printer [name]...
668 disable type-printer [name]...
669 Enable or disable type printers.
673 ** For the Renesas Super-H architecture, the "regs" command has been removed
674 (has been deprecated in GDB 7.5), and "info all-registers" should be used
679 set print type methods (on|off)
680 show print type methods
681 Control whether method declarations are displayed by "ptype".
682 The default is to show them.
684 set print type typedefs (on|off)
685 show print type typedefs
686 Control whether typedef definitions are displayed by "ptype".
687 The default is to show them.
689 set filename-display basename|relative|absolute
690 show filename-display
691 Control the way in which filenames is displayed.
692 The default is "relative", which preserves previous behavior.
694 set trace-buffer-size
695 show trace-buffer-size
696 Request target to change the size of trace buffer.
698 set remote trace-buffer-size-packet auto|on|off
699 show remote trace-buffer-size-packet
700 Control the use of the remote protocol `QTBuffer:size' packet.
704 Control display of debugging messages related to ARM AArch64.
707 set debug coff-pe-read
708 show debug coff-pe-read
709 Control display of debugging messages related to reading of COFF/PE
714 Control display of debugging messages related to Mach-O symbols
717 set debug notification
718 show debug notification
719 Control display of debugging info for async remote notification.
723 ** Command parameter changes are now notified using new async record
724 "=cmd-param-changed".
725 ** Trace frame changes caused by command "tfind" are now notified using
726 new async record "=traceframe-changed".
727 ** The creation, deletion and modification of trace state variables
728 are now notified using new async records "=tsv-created",
729 "=tsv-deleted" and "=tsv-modified".
730 ** The start and stop of process record are now notified using new
731 async record "=record-started" and "=record-stopped".
732 ** Memory changes are now notified using new async record
734 ** The data-disassemble command response will include a "fullname" field
735 containing the absolute file name when source has been requested.
736 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
737 command, to allow pattern filling of memory areas.
738 ** New commands "-catch-load"/"-catch-unload" added for intercepting
739 library load/unload events.
740 ** The response to breakpoint commands and breakpoint async records
741 includes an "installed" field containing a boolean state about each
742 non-pending tracepoint location is whether installed on target or not.
743 ** Output of the "-trace-status" command includes a "trace-file" field
744 containing the name of the trace file being examined. This field is
745 optional, and only present when examining a trace file.
746 ** The "fullname" field is now always present along with the "file" field,
747 even if the file cannot be found by GDB.
749 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
750 You must have the LZMA library available when configuring GDB for this
751 feature to be enabled. For more information, see:
752 http://fedoraproject.org/wiki/Features/MiniDebugInfo
757 Set the size of trace buffer. The remote stub reports support for this
758 packet to gdb's qSupported query.
761 Enable Branch Trace Store (BTS)-based branch tracing for the current
762 thread. The remote stub reports support for this packet to gdb's
766 Disable branch tracing for the current thread. The remote stub reports
767 support for this packet to gdb's qSupported query.
770 Read the traced branches for the current thread. The remote stub
771 reports support for this packet to gdb's qSupported query.
773 *** Changes in GDB 7.5
775 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
776 for more x32 ABI info.
778 * GDB now supports access to MIPS DSP registers on Linux targets.
780 * GDB now supports debugging microMIPS binaries.
782 * The "info os" command on GNU/Linux can now display information on
783 several new classes of objects managed by the operating system:
784 "info os procgroups" lists process groups
785 "info os files" lists file descriptors
786 "info os sockets" lists internet-domain sockets
787 "info os shm" lists shared-memory regions
788 "info os semaphores" lists semaphores
789 "info os msg" lists message queues
790 "info os modules" lists loaded kernel modules
792 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
793 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
794 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
795 options and inspect the probe arguments using the new $_probe_arg family
796 of convenience variables. You can obtain more information about SystemTap
797 in <http://sourceware.org/systemtap/>.
799 * GDB now supports reversible debugging on ARM, it allows you to
800 debug basic ARM and THUMB instructions, and provides
801 record/replay support.
803 * The option "symbol-reloading" has been deleted as it is no longer used.
807 ** GDB commands implemented in Python can now be put in command class
810 ** The "maint set python print-stack on|off" is now deleted.
812 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
813 apply "flag enum"-style pretty-printing to any enum.
815 ** gdb.lookup_symbol can now work when there is no current frame.
817 ** gdb.Symbol now has a 'line' attribute, holding the line number in
818 the source at which the symbol was defined.
820 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
821 method 'value'. The former indicates whether the symbol needs a
822 frame in order to compute its value, and the latter computes the
825 ** A new method 'referenced_value' on gdb.Value objects which can
826 dereference pointer as well as C++ reference values.
828 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
829 which return the global and static blocks (as gdb.Block objects),
830 of the underlying symbol table, respectively.
832 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
833 object associated with a PC value.
835 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
836 of the address range occupied by code for the current source line.
838 * Go language support.
839 GDB now supports debugging programs written in the Go programming
842 * GDBserver now supports stdio connections.
843 E.g. (gdb) target remote | ssh myhost gdbserver - hello
845 * The binary "gdbtui" can no longer be built or installed.
846 Use "gdb -tui" instead.
848 * GDB will now print "flag" enums specially. A flag enum is one where
849 all the enumerator values have no bits in common when pairwise
850 "and"ed. When printing a value whose type is a flag enum, GDB will
851 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
852 (gdb) print (enum E) 3
855 * The filename part of a linespec will now match trailing components
856 of a source file name. For example, "break gcc/expr.c:1000" will
857 now set a breakpoint in build/gcc/expr.c, but not
860 * The "info proc" and "generate-core-file" commands will now also
861 work on remote targets connected to GDBserver on Linux.
863 * The command "info catch" has been removed. It has been disabled
866 * The "catch exception" and "catch assert" commands now accept
867 a condition at the end of the command, much like the "break"
868 command does. For instance:
870 (gdb) catch exception Constraint_Error if Barrier = True
872 Previously, it was possible to add a condition to such catchpoints,
873 but it had to be done as a second step, after the catchpoint had been
874 created, using the "condition" command.
876 * The "info static-tracepoint-marker" command will now also work on
877 native Linux targets with in-process agent.
879 * GDB can now set breakpoints on inlined functions.
881 * The .gdb_index section has been updated to include symbols for
882 inlined functions. GDB will ignore older .gdb_index sections by
883 default, which could cause symbol files to be loaded more slowly
884 until their .gdb_index sections can be recreated. The new command
885 "set use-deprecated-index-sections on" will cause GDB to use any older
886 .gdb_index sections it finds. This will restore performance, but the
887 ability to set breakpoints on inlined functions will be lost in symbol
888 files with older .gdb_index sections.
890 The .gdb_index section has also been updated to record more information
891 about each symbol. This speeds up the "info variables", "info functions"
892 and "info types" commands when used with programs having the .gdb_index
893 section, as well as speeding up debugging with shared libraries using
894 the .gdb_index section.
896 * Ada support for GDB/MI Variable Objects has been added.
898 * GDB can now support 'breakpoint always-inserted mode' in 'record'
903 ** New command -info-os is the MI equivalent of "info os".
905 ** Output logs ("set logging" and related) now include MI output.
909 ** "set use-deprecated-index-sections on|off"
910 "show use-deprecated-index-sections on|off"
911 Controls the use of deprecated .gdb_index sections.
913 ** "catch load" and "catch unload" can be used to stop when a shared
914 library is loaded or unloaded, respectively.
916 ** "enable count" can be used to auto-disable a breakpoint after
919 ** "info vtbl" can be used to show the virtual method tables for
920 C++ and Java objects.
922 ** "explore" and its sub commands "explore value" and "explore type"
923 can be used to recursively explore values and types of
924 expressions. These commands are available only if GDB is
925 configured with '--with-python'.
927 ** "info auto-load" shows status of all kinds of auto-loaded files,
928 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
929 sequences of commands files, "info auto-load python-scripts"
930 shows status of auto-loading Python script files,
931 "info auto-load local-gdbinit" shows status of loading init file
932 (.gdbinit) from current directory and "info auto-load libthread-db" shows
933 status of inferior specific thread debugging shared library loading.
935 ** "info auto-load-scripts", "set auto-load-scripts on|off"
936 and "show auto-load-scripts" commands have been deprecated, use their
937 "info auto-load python-scripts", "set auto-load python-scripts on|off"
938 and "show auto-load python-scripts" counterparts instead.
940 ** "dprintf location,format,args..." creates a dynamic printf, which
941 is basically a breakpoint that does a printf and immediately
942 resumes your program's execution, so it is like a printf that you
943 can insert dynamically at runtime instead of at compiletime.
945 ** "set print symbol"
947 Controls whether GDB attempts to display the symbol, if any,
948 corresponding to addresses it prints. This defaults to "on", but
949 you can set it to "off" to restore GDB's previous behavior.
951 * Deprecated commands
953 ** For the Renesas Super-H architecture, the "regs" command has been
954 deprecated, and "info all-registers" should be used instead.
958 Renesas RL78 rl78-*-elf
959 HP OpenVMS ia64 ia64-hp-openvms*
961 * GDBserver supports evaluation of breakpoint conditions. When
962 support is advertised by GDBserver, GDB may be told to send the
963 breakpoint conditions in bytecode form to GDBserver. GDBserver
964 will only report the breakpoint trigger to GDB when its condition
970 show mips compression
971 Select the compressed ISA encoding used in functions that have no symbol
972 information available. The encoding can be set to either of:
975 and is updated automatically from ELF file flags if available.
977 set breakpoint condition-evaluation
978 show breakpoint condition-evaluation
979 Control whether breakpoint conditions are evaluated by GDB ("host") or by
980 GDBserver ("target"). Default option "auto" chooses the most efficient
982 This option can improve debugger efficiency depending on the speed of the
986 Disable auto-loading globally.
989 Show auto-loading setting of all kinds of auto-loaded files.
991 set auto-load gdb-scripts on|off
992 show auto-load gdb-scripts
993 Control auto-loading of GDB canned sequences of commands files.
995 set auto-load python-scripts on|off
996 show auto-load python-scripts
997 Control auto-loading of Python script files.
999 set auto-load local-gdbinit on|off
1000 show auto-load local-gdbinit
1001 Control loading of init file (.gdbinit) from current directory.
1003 set auto-load libthread-db on|off
1004 show auto-load libthread-db
1005 Control auto-loading of inferior specific thread debugging shared library.
1007 set auto-load scripts-directory <dir1>[:<dir2>...]
1008 show auto-load scripts-directory
1009 Set a list of directories from which to load auto-loaded scripts.
1010 Automatically loaded Python scripts and GDB scripts are located in one
1011 of the directories listed by this option.
1012 The delimiter (':' above) may differ according to the host platform.
1014 set auto-load safe-path <dir1>[:<dir2>...]
1015 show auto-load safe-path
1016 Set a list of directories from which it is safe to auto-load files.
1017 The delimiter (':' above) may differ according to the host platform.
1019 set debug auto-load on|off
1020 show debug auto-load
1021 Control display of debugging info for auto-loading the files above.
1023 set dprintf-style gdb|call|agent
1025 Control the way in which a dynamic printf is performed; "gdb"
1026 requests a GDB printf command, while "call" causes dprintf to call a
1027 function in the inferior. "agent" requests that the target agent
1028 (such as GDBserver) do the printing.
1030 set dprintf-function <expr>
1031 show dprintf-function
1032 set dprintf-channel <expr>
1033 show dprintf-channel
1034 Set the function and optional first argument to the call when using
1035 the "call" style of dynamic printf.
1037 set disconnected-dprintf on|off
1038 show disconnected-dprintf
1039 Control whether agent-style dynamic printfs continue to be in effect
1040 after GDB disconnects.
1042 * New configure options
1044 --with-auto-load-dir
1045 Configure default value for the 'set auto-load scripts-directory'
1046 setting above. It defaults to '$debugdir:$datadir/auto-load',
1047 $debugdir representing global debugging info directories (available
1048 via 'show debug-file-directory') and $datadir representing GDB's data
1049 directory (available via 'show data-directory').
1051 --with-auto-load-safe-path
1052 Configure default value for the 'set auto-load safe-path' setting
1053 above. It defaults to the --with-auto-load-dir setting.
1055 --without-auto-load-safe-path
1056 Set 'set auto-load safe-path' to '/', effectively disabling this
1059 * New remote packets
1061 z0/z1 conditional breakpoints extension
1063 The z0/z1 breakpoint insertion packets have been extended to carry
1064 a list of conditional expressions over to the remote stub depending on the
1065 condition evaluation mode. The use of this extension can be controlled
1066 via the "set remote conditional-breakpoints-packet" command.
1070 Specify the signals which the remote stub may pass to the debugged
1071 program without GDB involvement.
1073 * New command line options
1075 --init-command=FILE, -ix Like --command, -x but execute it
1076 before loading inferior.
1077 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1078 execute it before loading inferior.
1080 *** Changes in GDB 7.4
1082 * GDB now handles ambiguous linespecs more consistently; the existing
1083 FILE:LINE support has been expanded to other types of linespecs. A
1084 breakpoint will now be set on all matching locations in all
1085 inferiors, and locations will be added or removed according to
1088 * GDB now allows you to skip uninteresting functions and files when
1089 stepping with the "skip function" and "skip file" commands.
1091 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1092 and "show remote hardware-watchpoint-length-limit". These allows to
1093 set or show the maximum length limit (in bytes) of a remote
1094 target hardware watchpoint.
1096 This allows e.g. to use "unlimited" hardware watchpoints with the
1097 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1098 watchpoints are slower than real hardware watchpoints but are
1099 significantly faster than gdb software watchpoints.
1103 ** The register_pretty_printer function in module gdb.printing now takes
1104 an optional `replace' argument. If True, the new printer replaces any
1107 ** The "maint set python print-stack on|off" command has been
1108 deprecated and will be deleted in GDB 7.5.
1109 A new command: "set python print-stack none|full|message" has
1110 replaced it. Additionally, the default for "print-stack" is
1111 now "message", which just prints the error message without
1114 ** A prompt substitution hook (prompt_hook) is now available to the
1117 ** A new Python module, gdb.prompt has been added to the GDB Python
1118 modules library. This module provides functionality for
1119 escape sequences in prompts (used by set/show
1120 extended-prompt). These escape sequences are replaced by their
1121 corresponding value.
1123 ** Python commands and convenience-functions located in
1124 'data-directory'/python/gdb/command and
1125 'data-directory'/python/gdb/function are now automatically loaded
1128 ** Blocks now provide four new attributes. global_block and
1129 static_block will return the global and static blocks
1130 respectively. is_static and is_global are boolean attributes
1131 that indicate if the block is one of those two types.
1133 ** Symbols now provide the "type" attribute, the type of the symbol.
1135 ** The "gdb.breakpoint" function has been deprecated in favor of
1138 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1139 of a function. This class is based on the "finish" command
1140 available in the CLI.
1142 ** Type objects for struct and union types now allow access to
1143 the fields using standard Python dictionary (mapping) methods.
1144 For example, "some_type['myfield']" now works, as does
1145 "some_type.items()".
1147 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1150 ** A new function, "deep_items" has been added to the gdb.types
1151 module in the GDB Python modules library. This function returns
1152 an iterator over the fields of a struct or union type. Unlike
1153 the standard Python "iteritems" method, it will recursively traverse
1154 any anonymous fields.
1158 ** "*stopped" events can report several new "reason"s, such as
1161 ** Breakpoint changes are now notified using new async records, like
1162 "=breakpoint-modified".
1164 ** New command -ada-task-info.
1166 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1167 $sdir specifies the default system locations of shared libraries.
1168 $pdir specifies the directory where the libpthread used by the application
1171 GDB no longer looks in $sdir and $pdir after it has searched the directories
1172 mentioned in libthread-db-search-path. If you want to search those
1173 directories, they must be specified in libthread-db-search-path.
1174 The default value of libthread-db-search-path on GNU/Linux and Solaris
1175 systems is now "$sdir:$pdir".
1177 $pdir is not supported by gdbserver, it is currently ignored.
1178 $sdir is supported by gdbserver.
1180 * New configure option --with-iconv-bin.
1181 When using the internationalization support like the one in the GNU C
1182 library, GDB will invoke the "iconv" program to get a list of supported
1183 character sets. If this program lives in a non-standard location, one can
1184 use this option to specify where to find it.
1186 * When natively debugging programs on PowerPC BookE processors running
1187 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1188 watchpoints, which specify a mask in addition to an address to watch.
1189 The mask specifies that some bits of an address (the bits which are
1190 reset in the mask) should be ignored when matching the address accessed
1191 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1192 section in the user manual for more details.
1194 * The new option --once causes GDBserver to stop listening for connections once
1195 the first connection is made. The listening port used by GDBserver will
1196 become available after that.
1198 * New commands "info macros" and "alias" have been added.
1200 * New function parameters suffix @entry specifies value of function parameter
1201 at the time the function got called. Entry values are available only since
1207 "!" is now an alias of the "shell" command.
1208 Note that no space is needed between "!" and SHELL COMMAND.
1212 watch EXPRESSION mask MASK_VALUE
1213 The watch command now supports the mask argument which allows creation
1214 of masked watchpoints, if the current architecture supports this feature.
1216 info auto-load-scripts [REGEXP]
1217 This command was formerly named "maintenance print section-scripts".
1218 It is now generally useful and is no longer a maintenance-only command.
1220 info macro [-all] [--] MACRO
1221 The info macro command has new options `-all' and `--'. The first for
1222 printing all definitions of a macro. The second for explicitly specifying
1223 the end of arguments and the beginning of the macro name in case the macro
1224 name starts with a hyphen.
1226 collect[/s] EXPRESSIONS
1227 The tracepoint collect command now takes an optional modifier "/s"
1228 that directs it to dereference pointer-to-character types and
1229 collect the bytes of memory up to a zero byte. The behavior is
1230 similar to what you see when you use the regular print command on a
1231 string. An optional integer following the "/s" sets a bound on the
1232 number of bytes that will be collected.
1235 The trace start command now interprets any supplied arguments as a
1236 note to be recorded with the trace run, with an effect similar to
1237 setting the variable trace-notes.
1240 The trace stop command now interprets any arguments as a note to be
1241 mentioned along with the tstatus report that the trace was stopped
1242 with a command. The effect is similar to setting the variable
1245 * Tracepoints can now be enabled and disabled at any time after a trace
1246 experiment has been started using the standard "enable" and "disable"
1247 commands. It is now possible to start a trace experiment with no enabled
1248 tracepoints; GDB will display a warning, but will allow the experiment to
1249 begin, assuming that tracepoints will be enabled as needed while the trace
1252 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1253 locations with 4-byte instructions, when they were previously
1254 limited to locations with instructions of 5 bytes or longer.
1258 set debug dwarf2-read
1259 show debug dwarf2-read
1260 Turns on or off display of debugging messages related to reading
1261 DWARF debug info. The default is off.
1263 set debug symtab-create
1264 show debug symtab-create
1265 Turns on or off display of debugging messages related to symbol table
1266 creation. The default is off.
1269 show extended-prompt
1270 Set the GDB prompt, and allow escape sequences to be inserted to
1271 display miscellaneous information (see 'help set extended-prompt'
1272 for the list of sequences). This prompt (and any information
1273 accessed through the escape sequences) is updated every time the
1274 prompt is displayed.
1276 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1277 show print entry-values
1278 Set printing of frame argument values at function entry. In some cases
1279 GDB can determine the value of function argument which was passed by the
1280 function caller, even if the value was modified inside the called function.
1282 set debug entry-values
1283 show debug entry-values
1284 Control display of debugging info for determining frame argument values at
1285 function entry and virtual tail call frames.
1287 set basenames-may-differ
1288 show basenames-may-differ
1289 Set whether a source file may have multiple base names.
1290 (A "base name" is the name of a file with the directory part removed.
1291 Example: The base name of "/home/user/hello.c" is "hello.c".)
1292 If set, GDB will canonicalize file names (e.g., expand symlinks)
1293 before comparing them. Canonicalization is an expensive operation,
1294 but it allows the same file be known by more than one base name.
1295 If not set (the default), all source files are assumed to have just
1296 one base name, and gdb will do file name comparisons more efficiently.
1302 Set a user name and notes for the current and any future trace runs.
1303 This is useful for long-running and/or disconnected traces, to
1304 inform others (or yourself) as to who is running the trace, supply
1305 contact information, or otherwise explain what is going on.
1307 set trace-stop-notes
1308 show trace-stop-notes
1309 Set a note attached to the trace run, that is displayed when the
1310 trace has been stopped by a tstop command. This is useful for
1311 instance as an explanation, if you are stopping a trace run that was
1312 started by someone else.
1314 * New remote packets
1318 Dynamically enable a tracepoint in a started trace experiment.
1322 Dynamically disable a tracepoint in a started trace experiment.
1326 Set the user and notes of the trace run.
1330 Query the current status of a tracepoint.
1334 Query the minimum length of instruction at which a fast tracepoint may
1337 * Dcache size (number of lines) and line-size are now runtime-configurable
1338 via "set dcache line" and "set dcache line-size" commands.
1342 Texas Instruments TMS320C6x tic6x-*-*
1346 Renesas RL78 rl78-*-elf
1348 *** Changes in GDB 7.3.1
1350 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1352 *** Changes in GDB 7.3
1354 * GDB has a new command: "thread find [REGEXP]".
1355 It finds the thread id whose name, target id, or thread extra info
1356 matches the given regular expression.
1358 * The "catch syscall" command now works on mips*-linux* targets.
1360 * The -data-disassemble MI command now supports modes 2 and 3 for
1361 dumping the instruction opcodes.
1363 * New command line options
1365 -data-directory DIR Specify DIR as the "data-directory".
1366 This is mostly for testing purposes.
1368 * The "maint set python auto-load on|off" command has been renamed to
1369 "set auto-load-scripts on|off".
1371 * GDB has a new command: "set directories".
1372 It is like the "dir" command except that it replaces the
1373 source path list instead of augmenting it.
1375 * GDB now understands thread names.
1377 On GNU/Linux, "info threads" will display the thread name as set by
1378 prctl or pthread_setname_np.
1380 There is also a new command, "thread name", which can be used to
1381 assign a name internally for GDB to display.
1384 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1385 has been integrated into GDB.
1389 ** The function gdb.Write now accepts an optional keyword 'stream'.
1390 This keyword, when provided, will direct the output to either
1391 stdout, stderr, or GDB's logging output.
1393 ** Parameters can now be be sub-classed in Python, and in particular
1394 you may implement the get_set_doc and get_show_doc functions.
1395 This improves how Parameter set/show documentation is processed
1396 and allows for more dynamic content.
1398 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1399 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1400 have an is_valid method.
1402 ** Breakpoints can now be sub-classed in Python, and in particular
1403 you may implement a 'stop' function that is executed each time
1404 the inferior reaches that breakpoint.
1406 ** New function gdb.lookup_global_symbol looks up a global symbol.
1408 ** GDB values in Python are now callable if the value represents a
1409 function. For example, if 'some_value' represents a function that
1410 takes two integer parameters and returns a value, you can call
1411 that function like so:
1413 result = some_value (10,20)
1415 ** Module gdb.types has been added.
1416 It contains a collection of utilities for working with gdb.Types objects:
1417 get_basic_type, has_field, make_enum_dict.
1419 ** Module gdb.printing has been added.
1420 It contains utilities for writing and registering pretty-printers.
1421 New classes: PrettyPrinter, SubPrettyPrinter,
1422 RegexpCollectionPrettyPrinter.
1423 New function: register_pretty_printer.
1425 ** New commands "info pretty-printers", "enable pretty-printer" and
1426 "disable pretty-printer" have been added.
1428 ** gdb.parameter("directories") is now available.
1430 ** New function gdb.newest_frame returns the newest frame in the
1433 ** The gdb.InferiorThread class has a new "name" attribute. This
1434 holds the thread's name.
1436 ** Python Support for Inferior events.
1437 Python scripts can add observers to be notified of events
1438 occurring in the process being debugged.
1439 The following events are currently supported:
1440 - gdb.events.cont Continue event.
1441 - gdb.events.exited Inferior exited event.
1442 - gdb.events.stop Signal received, and Breakpoint hit events.
1446 ** GDB now puts template parameters in scope when debugging in an
1447 instantiation. For example, if you have:
1449 template<int X> int func (void) { return X; }
1451 then if you step into func<5>, "print X" will show "5". This
1452 feature requires proper debuginfo support from the compiler; it
1453 was added to GCC 4.5.
1455 ** The motion commands "next", "finish", "until", and "advance" now
1456 work better when exceptions are thrown. In particular, GDB will
1457 no longer lose control of the inferior; instead, the GDB will
1458 stop the inferior at the point at which the exception is caught.
1459 This functionality requires a change in the exception handling
1460 code that was introduced in GCC 4.5.
1462 * GDB now follows GCC's rules on accessing volatile objects when
1463 reading or writing target state during expression evaluation.
1464 One notable difference to prior behavior is that "print x = 0"
1465 no longer generates a read of x; the value of the assignment is
1466 now always taken directly from the value being assigned.
1468 * GDB now has some support for using labels in the program's source in
1469 linespecs. For instance, you can use "advance label" to continue
1470 execution to a label.
1472 * GDB now has support for reading and writing a new .gdb_index
1473 section. This section holds a fast index of DWARF debugging
1474 information and can be used to greatly speed up GDB startup and
1475 operation. See the documentation for `save gdb-index' for details.
1477 * The "watch" command now accepts an optional "-location" argument.
1478 When used, this causes GDB to watch the memory referred to by the
1479 expression. Such a watchpoint is never deleted due to it going out
1482 * GDB now supports thread debugging of core dumps on GNU/Linux.
1484 GDB now activates thread debugging using the libthread_db library
1485 when debugging GNU/Linux core dumps, similarly to when debugging
1486 live processes. As a result, when debugging a core dump file, GDB
1487 is now able to display pthread_t ids of threads. For example, "info
1488 threads" shows the same output as when debugging the process when it
1489 was live. In earlier releases, you'd see something like this:
1492 * 1 LWP 6780 main () at main.c:10
1494 While now you see this:
1497 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1499 It is also now possible to inspect TLS variables when debugging core
1502 When debugging a core dump generated on a machine other than the one
1503 used to run GDB, you may need to point GDB at the correct
1504 libthread_db library with the "set libthread-db-search-path"
1505 command. See the user manual for more details on this command.
1507 * When natively debugging programs on PowerPC BookE processors running
1508 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1509 which stop execution of the inferior whenever it executes an instruction
1510 at any address within the specified range. See the "PowerPC Embedded"
1511 section in the user manual for more details.
1513 * New features in the GDB remote stub, GDBserver
1515 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1516 and i686 LynxOS (version 5.x).
1518 ** GDBserver is now supported on Blackfin Linux.
1520 * New native configurations
1522 ia64 HP-UX ia64-*-hpux*
1526 Analog Devices, Inc. Blackfin Processor bfin-*
1528 * Ada task switching is now supported on sparc-elf targets when
1529 debugging a program using the Ravenscar Profile. For more information,
1530 see the "Tasking Support when using the Ravenscar Profile" section
1531 in the GDB user manual.
1533 * Guile support was removed.
1535 * New features in the GNU simulator
1537 ** The --map-info flag lists all known core mappings.
1539 ** CFI flashes may be simulated via the "cfi" device.
1541 *** Changes in GDB 7.2
1543 * Shared library support for remote targets by default
1545 When GDB is configured for a generic, non-OS specific target, like
1546 for example, --target=arm-eabi or one of the many *-*-elf targets,
1547 GDB now queries remote stubs for loaded shared libraries using the
1548 `qXfer:libraries:read' packet. Previously, shared library support
1549 was always disabled for such configurations.
1553 ** Argument Dependent Lookup (ADL)
1555 In C++ ADL lookup directs function search to the namespaces of its
1556 arguments even if the namespace has not been imported.
1566 Here the compiler will search for `foo' in the namespace of 'b'
1567 and find A::foo. GDB now supports this. This construct is commonly
1568 used in the Standard Template Library for operators.
1570 ** Improved User Defined Operator Support
1572 In addition to member operators, GDB now supports lookup of operators
1573 defined in a namespace and imported with a `using' directive, operators
1574 defined in the global scope, operators imported implicitly from an
1575 anonymous namespace, and the ADL operators mentioned in the previous
1577 GDB now also supports proper overload resolution for all the previously
1578 mentioned flavors of operators.
1580 ** static const class members
1582 Printing of static const class members that are initialized in the
1583 class definition has been fixed.
1585 * Windows Thread Information Block access.
1587 On Windows targets, GDB now supports displaying the Windows Thread
1588 Information Block (TIB) structure. This structure is visible either
1589 by using the new command `info w32 thread-information-block' or, by
1590 dereferencing the new convenience variable named `$_tlb', a
1591 thread-specific pointer to the TIB. This feature is also supported
1592 when remote debugging using GDBserver.
1594 * Static tracepoints
1596 Static tracepoints are calls in the user program into a tracing
1597 library. One such library is a port of the LTTng kernel tracer to
1598 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1599 When debugging with GDBserver, GDB now supports combining the GDB
1600 tracepoint machinery with such libraries. For example: the user can
1601 use GDB to probe a static tracepoint marker (a call from the user
1602 program into the tracing library) with the new "strace" command (see
1603 "New commands" below). This creates a "static tracepoint" in the
1604 breakpoint list, that can be manipulated with the same feature set
1605 as fast and regular tracepoints. E.g., collect registers, local and
1606 global variables, collect trace state variables, and define
1607 tracepoint conditions. In addition, the user can collect extra
1608 static tracepoint marker specific data, by collecting the new
1609 $_sdata internal variable. When analyzing the trace buffer, you can
1610 inspect $_sdata like any other variable available to GDB. For more
1611 information, see the "Tracepoints" chapter in GDB user manual. New
1612 remote packets have been defined to support static tracepoints, see
1613 the "New remote packets" section below.
1615 * Better reconstruction of tracepoints after disconnected tracing
1617 GDB will attempt to download the original source form of tracepoint
1618 definitions when starting a trace run, and then will upload these
1619 upon reconnection to the target, resulting in a more accurate
1620 reconstruction of the tracepoints that are in use on the target.
1624 You can now exercise direct control over the ways that GDB can
1625 affect your program. For instance, you can disallow the setting of
1626 breakpoints, so that the program can run continuously (assuming
1627 non-stop mode). In addition, the "observer" variable is available
1628 to switch all of the different controls; in observer mode, GDB
1629 cannot affect the target's behavior at all, which is useful for
1630 tasks like diagnosing live systems in the field.
1632 * The new convenience variable $_thread holds the number of the
1635 * New remote packets
1639 Return the address of the Windows Thread Information Block of a given thread.
1643 In response to several of the tracepoint packets, the target may now
1644 also respond with a number of intermediate `qRelocInsn' request
1645 packets before the final result packet, to have GDB handle
1646 relocating an instruction to execute at a different address. This
1647 is particularly useful for stubs that support fast tracepoints. GDB
1648 reports support for this feature in the qSupported packet.
1652 List static tracepoint markers in the target program.
1656 List static tracepoint markers at a given address in the target
1659 qXfer:statictrace:read
1661 Read the static trace data collected (by a `collect $_sdata'
1662 tracepoint action). The remote stub reports support for this packet
1663 to gdb's qSupported query.
1667 Send the current settings of GDB's permission flags.
1671 Send part of the source (textual) form of a tracepoint definition,
1672 which includes location, conditional, and action list.
1674 * The source command now accepts a -s option to force searching for the
1675 script in the source search path even if the script name specifies
1678 * New features in the GDB remote stub, GDBserver
1680 - GDBserver now support tracepoints (including fast tracepoints, and
1681 static tracepoints). The feature is currently supported by the
1682 i386-linux and amd64-linux builds. See the "Tracepoints support
1683 in gdbserver" section in the manual for more information.
1685 GDBserver JIT compiles the tracepoint's conditional agent
1686 expression bytecode into native code whenever possible for low
1687 overhead dynamic tracepoints conditionals. For such tracepoints,
1688 an expression that examines program state is evaluated when the
1689 tracepoint is reached, in order to determine whether to capture
1690 trace data. If the condition is simple and false, processing the
1691 tracepoint finishes very quickly and no data is gathered.
1693 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1694 for static tracepoints support.
1696 - GDBserver now supports x86_64 Windows 64-bit debugging.
1698 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1699 it understands register description.
1701 * The --batch flag now disables pagination and queries.
1703 * X86 general purpose registers
1705 GDB now supports reading/writing byte, word and double-word x86
1706 general purpose registers directly. This means you can use, say,
1707 $ah or $ax to refer, respectively, to the byte register AH and
1708 16-bit word register AX that are actually portions of the 32-bit
1709 register EAX or 64-bit register RAX.
1711 * The `commands' command now accepts a range of breakpoints to modify.
1712 A plain `commands' following a command that creates multiple
1713 breakpoints affects all the breakpoints set by that command. This
1714 applies to breakpoints set by `rbreak', and also applies when a
1715 single `break' command creates multiple breakpoints (e.g.,
1716 breakpoints on overloaded c++ functions).
1718 * The `rbreak' command now accepts a filename specification as part of
1719 its argument, limiting the functions selected by the regex to those
1720 in the specified file.
1722 * Support for remote debugging Windows and SymbianOS shared libraries
1723 from Unix hosts has been improved. Non Windows GDB builds now can
1724 understand target reported file names that follow MS-DOS based file
1725 system semantics, such as file names that include drive letters and
1726 use the backslash character as directory separator. This makes it
1727 possible to transparently use the "set sysroot" and "set
1728 solib-search-path" on Unix hosts to point as host copies of the
1729 target's shared libraries. See the new command "set
1730 target-file-system-kind" described below, and the "Commands to
1731 specify files" section in the user manual for more information.
1735 eval template, expressions...
1736 Convert the values of one or more expressions under the control
1737 of the string template to a command line, and call it.
1739 set target-file-system-kind unix|dos-based|auto
1740 show target-file-system-kind
1741 Set or show the assumed file system kind for target reported file
1744 save breakpoints <filename>
1745 Save all current breakpoint definitions to a file suitable for use
1746 in a later debugging session. To read the saved breakpoint
1747 definitions, use the `source' command.
1749 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1752 info static-tracepoint-markers
1753 Display information about static tracepoint markers in the target.
1755 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1756 Define a static tracepoint by probing a marker at the given
1757 function, line, address, or marker ID.
1761 Enable and disable observer mode.
1763 set may-write-registers on|off
1764 set may-write-memory on|off
1765 set may-insert-breakpoints on|off
1766 set may-insert-tracepoints on|off
1767 set may-insert-fast-tracepoints on|off
1768 set may-interrupt on|off
1769 Set individual permissions for GDB effects on the target. Note that
1770 some of these settings can have undesirable or surprising
1771 consequences, particularly when changed in the middle of a session.
1772 For instance, disabling the writing of memory can prevent
1773 breakpoints from being inserted, cause single-stepping to fail, or
1774 even crash your program, if you disable after breakpoints have been
1775 inserted. However, GDB should not crash.
1777 set record memory-query on|off
1778 show record memory-query
1779 Control whether to stop the inferior if memory changes caused
1780 by an instruction cannot be recorded.
1785 The disassemble command now supports "start,+length" form of two arguments.
1789 ** GDB now provides a new directory location, called the python directory,
1790 where Python scripts written for GDB can be installed. The location
1791 of that directory is <data-directory>/python, where <data-directory>
1792 is the GDB data directory. For more details, see section `Scripting
1793 GDB using Python' in the manual.
1795 ** The GDB Python API now has access to breakpoints, symbols, symbol
1796 tables, program spaces, inferiors, threads and frame's code blocks.
1797 Additionally, GDB Parameters can now be created from the API, and
1798 manipulated via set/show in the CLI.
1800 ** New functions gdb.target_charset, gdb.target_wide_charset,
1801 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1803 ** New exception gdb.GdbError.
1805 ** Pretty-printers are now also looked up in the current program space.
1807 ** Pretty-printers can now be individually enabled and disabled.
1809 ** GDB now looks for names of Python scripts to auto-load in a
1810 special section named `.debug_gdb_scripts', in addition to looking
1811 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1813 * Tracepoint actions were unified with breakpoint commands. In particular,
1814 there are no longer differences in "info break" output for breakpoints and
1815 tracepoints and the "commands" command can be used for both tracepoints and
1816 regular breakpoints.
1820 ARM Symbian arm*-*-symbianelf*
1822 * D language support.
1823 GDB now supports debugging programs written in the D programming
1826 * GDB now supports the extended ptrace interface for PowerPC which is
1827 available since Linux kernel version 2.6.34. This automatically enables
1828 any hardware breakpoints and additional hardware watchpoints available in
1829 the processor. The old ptrace interface exposes just one hardware
1830 watchpoint and no hardware breakpoints.
1832 * GDB is now able to use the Data Value Compare (DVC) register available on
1833 embedded PowerPC processors to implement in hardware simple watchpoint
1834 conditions of the form:
1836 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1838 This works in native GDB running on Linux kernels with the extended ptrace
1839 interface mentioned above.
1841 *** Changes in GDB 7.1
1845 ** Namespace Support
1847 GDB now supports importing of namespaces in C++. This enables the
1848 user to inspect variables from imported namespaces. Support for
1849 namepace aliasing has also been added. So, if a namespace is
1850 aliased in the current scope (e.g. namepace C=A; ) the user can
1851 print variables using the alias (e.g. (gdb) print C::x).
1855 All known bugs relating to the printing of virtual base class were
1856 fixed. It is now possible to call overloaded static methods using a
1861 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1862 and reinterpret_cast<> are now handled by the C++ expression parser.
1866 Xilinx MicroBlaze microblaze-*-*
1871 Xilinx MicroBlaze microblaze
1874 * Multi-program debugging.
1876 GDB now has support for multi-program (a.k.a. multi-executable or
1877 multi-exec) debugging. This allows for debugging multiple inferiors
1878 simultaneously each running a different program under the same GDB
1879 session. See "Debugging Multiple Inferiors and Programs" in the
1880 manual for more information. This implied some user visible changes
1881 in the multi-inferior support. For example, "info inferiors" now
1882 lists inferiors that are not running yet or that have exited
1883 already. See also "New commands" and "New options" below.
1885 * New tracing features
1887 GDB's tracepoint facility now includes several new features:
1889 ** Trace state variables
1891 GDB tracepoints now include support for trace state variables, which
1892 are variables managed by the target agent during a tracing
1893 experiment. They are useful for tracepoints that trigger each
1894 other, so for instance one tracepoint can count hits in a variable,
1895 and then a second tracepoint has a condition that is true when the
1896 count reaches a particular value. Trace state variables share the
1897 $-syntax of GDB convenience variables, and can appear in both
1898 tracepoint actions and condition expressions. Use the "tvariable"
1899 command to create, and "info tvariables" to view; see "Trace State
1900 Variables" in the manual for more detail.
1904 GDB now includes an option for defining fast tracepoints, which
1905 targets may implement more efficiently, such as by installing a jump
1906 into the target agent rather than a trap instruction. The resulting
1907 speedup can be by two orders of magnitude or more, although the
1908 tradeoff is that some program locations on some target architectures
1909 might not allow fast tracepoint installation, for instance if the
1910 instruction to be replaced is shorter than the jump. To request a
1911 fast tracepoint, use the "ftrace" command, with syntax identical to
1912 the regular trace command.
1914 ** Disconnected tracing
1916 It is now possible to detach GDB from the target while it is running
1917 a trace experiment, then reconnect later to see how the experiment
1918 is going. In addition, a new variable disconnected-tracing lets you
1919 tell the target agent whether to continue running a trace if the
1920 connection is lost unexpectedly.
1924 GDB now has the ability to save the trace buffer into a file, and
1925 then use that file as a target, similarly to you can do with
1926 corefiles. You can select trace frames, print data that was
1927 collected in them, and use tstatus to display the state of the
1928 tracing run at the moment that it was saved. To create a trace
1929 file, use "tsave <filename>", and to use it, do "target tfile
1932 ** Circular trace buffer
1934 You can ask the target agent to handle the trace buffer as a
1935 circular buffer, discarding the oldest trace frames to make room for
1936 newer ones, by setting circular-trace-buffer to on. This feature may
1937 not be available for all target agents.
1942 The disassemble command, when invoked with two arguments, now requires
1943 the arguments to be comma-separated.
1946 The info variables command now displays variable definitions. Files
1947 which only declare a variable are not shown.
1950 The source command is now capable of sourcing Python scripts.
1951 This feature is dependent on the debugger being build with Python
1954 Related to this enhancement is also the introduction of a new command
1955 "set script-extension" (see below).
1957 * New commands (for set/show, see "New options" below)
1959 record save [<FILENAME>]
1960 Save a file (in core file format) containing the process record
1961 execution log for replay debugging at a later time.
1963 record restore <FILENAME>
1964 Restore the process record execution log that was saved at an
1965 earlier time, for replay debugging.
1967 add-inferior [-copies <N>] [-exec <FILENAME>]
1970 clone-inferior [-copies <N>] [ID]
1971 Make a new inferior ready to execute the same program another
1972 inferior has loaded.
1977 maint info program-spaces
1978 List the program spaces loaded into GDB.
1980 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1981 show remote interrupt-sequence
1982 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1983 as the sequence to the remote target in order to interrupt the execution.
1984 Ctrl-C is a default. Some system prefers BREAK which is high level of
1985 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1986 Magic SysRq g. It is BREAK signal and character 'g'.
1988 set remote interrupt-on-connect [on | off]
1989 show remote interrupt-on-connect
1990 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1991 remote target when gdb connects to it. This is needed when you debug
1994 set remotebreak [on | off]
1996 Deprecated. Use "set/show remote interrupt-sequence" instead.
1998 tvariable $NAME [ = EXP ]
1999 Create or modify a trace state variable.
2002 List trace state variables and their values.
2004 delete tvariable $NAME ...
2005 Delete one or more trace state variables.
2008 Evaluate the given expressions without collecting anything into the
2009 trace buffer. (Valid in tracepoint actions only.)
2011 ftrace FN / FILE:LINE / *ADDR
2012 Define a fast tracepoint at the given function, line, or address.
2014 * New expression syntax
2016 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2017 GDB now parses 0b101010 identically with 42.
2021 set follow-exec-mode new|same
2022 show follow-exec-mode
2023 Control whether GDB reuses the same inferior across an exec call or
2024 creates a new one. This is useful to be able to restart the old
2025 executable after the inferior having done an exec call.
2027 set default-collect EXPR, ...
2028 show default-collect
2029 Define a list of expressions to be collected at each tracepoint.
2030 This is a useful way to ensure essential items are not overlooked,
2031 such as registers or a critical global variable.
2033 set disconnected-tracing
2034 show disconnected-tracing
2035 If set to 1, the target is instructed to continue tracing if it
2036 loses its connection to GDB. If 0, the target is to stop tracing
2039 set circular-trace-buffer
2040 show circular-trace-buffer
2041 If set to on, the target is instructed to use a circular trace buffer
2042 and discard the oldest trace frames instead of stopping the trace due
2043 to a full trace buffer. If set to off, the trace stops when the buffer
2044 fills up. Some targets may not support this.
2046 set script-extension off|soft|strict
2047 show script-extension
2048 If set to "off", the debugger does not perform any script language
2049 recognition, and all sourced files are assumed to be GDB scripts.
2050 If set to "soft" (the default), files are sourced according to
2051 filename extension, falling back to GDB scripts if the first
2053 If set to "strict", files are sourced according to filename extension.
2055 set ada trust-PAD-over-XVS on|off
2056 show ada trust-PAD-over-XVS
2057 If off, activate a workaround against a bug in the debugging information
2058 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2059 the GCC sources for more information about the GNAT encoding and
2060 PAD types in particular). It is always safe to set this option to
2061 off, but this introduces a slight performance penalty. The default
2064 * Python API Improvements
2066 ** GDB provides the new class gdb.LazyString. This is useful in
2067 some pretty-printing cases. The new method gdb.Value.lazy_string
2068 provides a simple way to create objects of this type.
2070 ** The fields returned by gdb.Type.fields now have an
2071 `is_base_class' attribute.
2073 ** The new method gdb.Type.range returns the range of an array type.
2075 ** The new method gdb.parse_and_eval can be used to parse and
2076 evaluate an expression.
2078 * New remote packets
2081 Define a trace state variable.
2084 Get the current value of a trace state variable.
2087 Set desired tracing behavior upon disconnection.
2090 Set the trace buffer to be linear or circular.
2093 Get data about the tracepoints currently in use.
2097 Process record now works correctly with hardware watchpoints.
2099 Multiple bug fixes have been made to the mips-irix port, making it
2100 much more reliable. In particular:
2101 - Debugging threaded applications is now possible again. Previously,
2102 GDB would hang while starting the program, or while waiting for
2103 the program to stop at a breakpoint.
2104 - Attaching to a running process no longer hangs.
2105 - An error occurring while loading a core file has been fixed.
2106 - Changing the value of the PC register now works again. This fixes
2107 problems observed when using the "jump" command, or when calling
2108 a function from GDB, or even when assigning a new value to $pc.
2109 - With the "finish" and "return" commands, the return value for functions
2110 returning a small array is now correctly printed.
2111 - It is now possible to break on shared library code which gets executed
2112 during a shared library init phase (code executed while executing
2113 their .init section). Previously, the breakpoint would have no effect.
2114 - GDB is now able to backtrace through the signal handler for
2115 non-threaded programs.
2117 PIE (Position Independent Executable) programs debugging is now supported.
2118 This includes debugging execution of PIC (Position Independent Code) shared
2119 libraries although for that, it should be possible to run such libraries as an
2122 *** Changes in GDB 7.0
2124 * GDB now has an interface for JIT compilation. Applications that
2125 dynamically generate code can create symbol files in memory and register
2126 them with GDB. For users, the feature should work transparently, and
2127 for JIT developers, the interface is documented in the GDB manual in the
2128 "JIT Compilation Interface" chapter.
2130 * Tracepoints may now be conditional. The syntax is as for
2131 breakpoints; either an "if" clause appended to the "trace" command,
2132 or the "condition" command is available. GDB sends the condition to
2133 the target for evaluation using the same bytecode format as is used
2134 for tracepoint actions.
2136 * The disassemble command now supports: an optional /r modifier, print the
2137 raw instructions in hex as well as in symbolic form, and an optional /m
2138 modifier to print mixed source+assembly.
2140 * Process record and replay
2142 In a architecture environment that supports ``process record and
2143 replay'', ``process record and replay'' target can record a log of
2144 the process execution, and replay it with both forward and reverse
2147 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2148 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2149 set execution-direction {forward|reverse}, for targets that support
2152 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2153 feature is available with a native GDB running on kernel version
2156 * GDB now has support for multi-byte and wide character sets on the
2157 target. Strings whose character type is wchar_t, char16_t, or
2158 char32_t are now correctly printed. GDB supports wide- and unicode-
2159 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2160 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2161 `printf'. This feature requires iconv to work properly; if your
2162 system does not have a working iconv, GDB can use GNU libiconv. See
2163 the installation instructions for more information.
2165 * GDB now supports automatic retrieval of shared library files from
2166 remote targets. To use this feature, specify a system root that begins
2167 with the `remote:' prefix, either via the `set sysroot' command or via
2168 the `--with-sysroot' configure-time option.
2170 * "info sharedlibrary" now takes an optional regex of libraries to show,
2171 and it now reports if a shared library has no debugging information.
2173 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2174 now complete on file names.
2176 * When completing in expressions, gdb will attempt to limit
2177 completions to allowable structure or union fields, where appropriate.
2178 For instance, consider:
2180 # struct example { int f1; double f2; };
2181 # struct example variable;
2184 If the user types TAB at the end of this command line, the available
2185 completions will be "f1" and "f2".
2187 * Inlined functions are now supported. They show up in backtraces, and
2188 the "step", "next", and "finish" commands handle them automatically.
2190 * GDB now supports the token-splicing (##) and stringification (#)
2191 operators when expanding macros. It also supports variable-arity
2194 * GDB now supports inspecting extra signal information, exported by
2195 the new $_siginfo convenience variable. The feature is currently
2196 implemented on linux ARM, i386 and amd64.
2198 * GDB can now display the VFP floating point registers and NEON vector
2199 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2200 can provide these registers (requires Linux 2.6.30 or later). Remote
2201 and simulator targets may also provide them.
2203 * New remote packets
2206 Search memory for a sequence of bytes.
2209 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2210 operation over reliable transport links. Use of this packet is
2211 controlled by the `set remote noack-packet' command.
2214 Kill the process with the specified process ID. Use this in preference
2215 to `k' when multiprocess protocol extensions are supported.
2218 Obtains additional operating system information
2222 Read or write additional signal information.
2224 * Removed remote protocol undocumented extension
2226 An undocumented extension to the remote protocol's `S' stop reply
2227 packet that permited the stub to pass a process id was removed.
2228 Remote servers should use the `T' stop reply packet instead.
2230 * GDB now supports multiple function calling conventions according to the
2231 DWARF-2 DW_AT_calling_convention function attribute.
2233 * The SH target utilizes the aforementioned change to distinguish between gcc
2234 and Renesas calling convention. It also adds the new CLI commands
2235 `set/show sh calling-convention'.
2237 * GDB can now read compressed debug sections, as produced by GNU gold
2238 with the --compress-debug-sections=zlib flag.
2240 * 64-bit core files are now supported on AIX.
2242 * Thread switching is now supported on Tru64.
2244 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2245 which will be allocated using malloc later in program execution.
2247 * The qXfer:libraries:read remote procotol packet now allows passing a
2248 list of section offsets.
2250 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2251 conditions handling signals delivered during attach or thread creation
2252 have also been fixed.
2254 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2255 From the user's standpoint, all unqualified instances of True and False
2256 are treated as the standard definitions, regardless of context.
2258 * GDB now parses C++ symbol and type names more flexibly. For
2261 template<typename T> class C { };
2264 GDB will now correctly handle all of:
2266 ptype C<char const *>
2267 ptype C<char const*>
2268 ptype C<const char *>
2269 ptype C<const char*>
2271 * New features in the GDB remote stub, gdbserver
2273 - The "--wrapper" command-line argument tells gdbserver to use a
2274 wrapper program to launch programs for debugging.
2276 - On PowerPC and S/390 targets, it is now possible to use a single
2277 gdbserver executable to debug both 32-bit and 64-bit programs.
2278 (This requires gdbserver itself to be built as a 64-bit executable.)
2280 - gdbserver uses the new noack protocol mode for TCP connections to
2281 reduce communications latency, if also supported and enabled in GDB.
2283 - Support for the sparc64-linux-gnu target is now included in
2286 - The amd64-linux build of gdbserver now supports debugging both
2287 32-bit and 64-bit programs.
2289 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2290 now support hardware watchpoints, and will use them automatically
2295 GDB now has support for scripting using Python. Whether this is
2296 available is determined at configure time.
2298 New GDB commands can now be written in Python.
2300 * Ada tasking support
2302 Ada tasks can now be inspected in GDB. The following commands have
2306 Print the list of Ada tasks.
2308 Print detailed information about task number N.
2310 Print the task number of the current task.
2312 Switch the context of debugging to task number N.
2314 * Support for user-defined prefixed commands. The "define" command can
2315 add new commands to existing prefixes, e.g. "target".
2317 * Multi-inferior, multi-process debugging.
2319 GDB now has generalized support for multi-inferior debugging. See
2320 "Debugging Multiple Inferiors" in the manual for more information.
2321 Although availability still depends on target support, the command
2322 set is more uniform now. The GNU/Linux specific multi-forks support
2323 has been migrated to this new framework. This implied some user
2324 visible changes; see "New commands" and also "Removed commands"
2327 * Target descriptions can now describe the target OS ABI. See the
2328 "Target Description Format" section in the user manual for more
2331 * Target descriptions can now describe "compatible" architectures
2332 to indicate that the target can execute applications for a different
2333 architecture in addition to those for the main target architecture.
2334 See the "Target Description Format" section in the user manual for
2337 * Multi-architecture debugging.
2339 GDB now includes general supports for debugging applications on
2340 hybrid systems that use more than one single processor architecture
2341 at the same time. Each such hybrid architecture still requires
2342 specific support to be added. The only hybrid architecture supported
2343 in this version of GDB is the Cell Broadband Engine.
2345 * GDB now supports integrated debugging of Cell/B.E. applications that
2346 use both the PPU and SPU architectures. To enable support for hybrid
2347 Cell/B.E. debugging, you need to configure GDB to support both the
2348 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2349 --enable-targets configure option.
2351 * Non-stop mode debugging.
2353 For some targets, GDB now supports an optional mode of operation in
2354 which you can examine stopped threads while other threads continue
2355 to execute freely. This is referred to as non-stop mode, with the
2356 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2357 section in the user manual for more information.
2359 To be able to support remote non-stop debugging, a remote stub needs
2360 to implement the non-stop mode remote protocol extensions, as
2361 described in the "Remote Non-Stop" section of the user manual. The
2362 GDB remote stub, gdbserver, has been adjusted to support these
2363 extensions on linux targets.
2365 * New commands (for set/show, see "New options" below)
2367 catch syscall [NAME(S) | NUMBER(S)]
2368 Catch system calls. Arguments, which should be names of system
2369 calls or their numbers, mean catch only those syscalls. Without
2370 arguments, every syscall will be caught. When the inferior issues
2371 any of the specified syscalls, GDB will stop and announce the system
2372 call, both when it is called and when its call returns. This
2373 feature is currently available with a native GDB running on the
2374 Linux Kernel, under the following architectures: x86, x86_64,
2375 PowerPC and PowerPC64.
2377 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2379 Search memory for a sequence of bytes.
2381 maint set python print-stack
2382 maint show python print-stack
2383 Show a stack trace when an error is encountered in a Python script.
2386 Invoke CODE by passing it to the Python interpreter.
2391 These allow macros to be defined, undefined, and listed
2395 Show operating system information about processes.
2398 List the inferiors currently under GDB's control.
2401 Switch focus to inferior number NUM.
2404 Detach from inferior number NUM.
2407 Kill inferior number NUM.
2411 set spu stop-on-load
2412 show spu stop-on-load
2413 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2415 set spu auto-flush-cache
2416 show spu auto-flush-cache
2417 Control whether to automatically flush the software-managed cache
2418 during Cell/B.E. debugging.
2420 set sh calling-convention
2421 show sh calling-convention
2422 Control the calling convention used when calling SH target functions.
2425 show debug timestamp
2426 Control display of timestamps with GDB debugging output.
2428 set disassemble-next-line
2429 show disassemble-next-line
2430 Control display of disassembled source lines or instructions when
2433 set remote noack-packet
2434 show remote noack-packet
2435 Set/show the use of remote protocol QStartNoAckMode packet. See above
2436 under "New remote packets."
2438 set remote query-attached-packet
2439 show remote query-attached-packet
2440 Control use of remote protocol `qAttached' (query-attached) packet.
2442 set remote read-siginfo-object
2443 show remote read-siginfo-object
2444 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2447 set remote write-siginfo-object
2448 show remote write-siginfo-object
2449 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2452 set remote reverse-continue
2453 show remote reverse-continue
2454 Control use of remote protocol 'bc' (reverse-continue) packet.
2456 set remote reverse-step
2457 show remote reverse-step
2458 Control use of remote protocol 'bs' (reverse-step) packet.
2460 set displaced-stepping
2461 show displaced-stepping
2462 Control displaced stepping mode. Displaced stepping is a way to
2463 single-step over breakpoints without removing them from the debuggee.
2464 Also known as "out-of-line single-stepping".
2467 show debug displaced
2468 Control display of debugging info for displaced stepping.
2470 maint set internal-error
2471 maint show internal-error
2472 Control what GDB does when an internal error is detected.
2474 maint set internal-warning
2475 maint show internal-warning
2476 Control what GDB does when an internal warning is detected.
2481 Use a wrapper program to launch programs for debugging.
2483 set multiple-symbols (all|ask|cancel)
2484 show multiple-symbols
2485 The value of this variable can be changed to adjust the debugger behavior
2486 when an expression or a breakpoint location contains an ambiguous symbol
2487 name (an overloaded function name, for instance).
2489 set breakpoint always-inserted
2490 show breakpoint always-inserted
2491 Keep breakpoints always inserted in the target, as opposed to inserting
2492 them when resuming the target, and removing them when the target stops.
2493 This option can improve debugger performance on slow remote targets.
2495 set arm fallback-mode (arm|thumb|auto)
2496 show arm fallback-mode
2497 set arm force-mode (arm|thumb|auto)
2499 These commands control how ARM GDB determines whether instructions
2500 are ARM or Thumb. The default for both settings is auto, which uses
2501 the current CPSR value for instructions without symbols; previous
2502 versions of GDB behaved as if "set arm fallback-mode arm".
2504 set disable-randomization
2505 show disable-randomization
2506 Standalone programs run with the virtual address space randomization enabled
2507 by default on some platforms. This option keeps the addresses stable across
2508 multiple debugging sessions.
2512 Control whether other threads are stopped or not when some thread hits
2517 Requests that asynchronous execution is enabled in the target, if available.
2518 In this case, it's possible to resume target in the background, and interact
2519 with GDB while the target is running. "show target-async" displays the
2520 current state of asynchronous execution of the target.
2522 set target-wide-charset
2523 show target-wide-charset
2524 The target-wide-charset is the name of the character set that GDB
2525 uses when printing characters whose type is wchar_t.
2527 set tcp auto-retry (on|off)
2529 set tcp connect-timeout
2530 show tcp connect-timeout
2531 These commands allow GDB to retry failed TCP connections to a remote stub
2532 with a specified timeout period; this is useful if the stub is launched
2533 in parallel with GDB but may not be ready to accept connections immediately.
2535 set libthread-db-search-path
2536 show libthread-db-search-path
2537 Control list of directories which GDB will search for appropriate
2540 set schedule-multiple (on|off)
2541 show schedule-multiple
2542 Allow GDB to resume all threads of all processes or only threads of
2543 the current process.
2547 Use more aggressive caching for accesses to the stack. This improves
2548 performance of remote debugging (particularly backtraces) without
2549 affecting correctness.
2551 set interactive-mode (on|off|auto)
2552 show interactive-mode
2553 Control whether GDB runs in interactive mode (on) or not (off).
2554 When in interactive mode, GDB waits for the user to answer all
2555 queries. Otherwise, GDB does not wait and assumes the default
2556 answer. When set to auto (the default), GDB determines which
2557 mode to use based on the stdin settings.
2562 For program forks, this is replaced by the new more generic `info
2563 inferiors' command. To list checkpoints, you can still use the
2564 `info checkpoints' command, which was an alias for the `info forks'
2568 Replaced by the new `inferior' command. To switch between
2569 checkpoints, you can still use the `restart' command, which was an
2570 alias for the `fork' command.
2573 This is removed, since some targets don't have a notion of
2574 processes. To switch between processes, you can still use the
2575 `inferior' command using GDB's own inferior number.
2578 For program forks, this is replaced by the new more generic `kill
2579 inferior' command. To delete a checkpoint, you can still use the
2580 `delete checkpoint' command, which was an alias for the `delete
2584 For program forks, this is replaced by the new more generic `detach
2585 inferior' command. To detach a checkpoint, you can still use the
2586 `detach checkpoint' command, which was an alias for the `detach
2589 * New native configurations
2591 x86/x86_64 Darwin i[34567]86-*-darwin*
2593 x86_64 MinGW x86_64-*-mingw*
2597 Lattice Mico32 lm32-*
2598 x86 DICOS i[34567]86-*-dicos*
2599 x86_64 DICOS x86_64-*-dicos*
2602 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2603 (mingw32ce) debugging.
2609 These commands were actually not implemented on any target.
2611 *** Changes in GDB 6.8
2613 * New native configurations
2615 NetBSD/hppa hppa*-*netbsd*
2616 Xtensa GNU/Linux xtensa*-*-linux*
2620 NetBSD/hppa hppa*-*-netbsd*
2621 Xtensa GNU/Lunux xtensa*-*-linux*
2623 * Change in command line behavior -- corefiles vs. process ids.
2625 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2626 attaching to process NUMBER fails, GDB no longer attempts to open a
2627 core file named NUMBER. Attaching to a program using the -c option
2628 is no longer supported. Instead, use the '-p' or '--pid' options.
2630 * GDB can now be built as a native debugger for debugging Windows x86
2631 (mingw32) Portable Executable (PE) programs.
2633 * Pending breakpoints no longer change their number when their address
2636 * GDB now supports breakpoints with multiple locations,
2637 including breakpoints on C++ constructors, inside C++ templates,
2638 and in inlined functions.
2640 * GDB's ability to debug optimized code has been improved. GDB more
2641 accurately identifies function bodies and lexical blocks that occupy
2642 more than one contiguous range of addresses.
2644 * Target descriptions can now describe registers for PowerPC.
2646 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2647 registers on PowerPC targets.
2649 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2650 targets even when the libthread_db library is not available.
2652 * The GDB remote stub, gdbserver, now supports the new file transfer
2653 commands (remote put, remote get, and remote delete).
2655 * The GDB remote stub, gdbserver, now supports run and attach in
2656 extended-remote mode.
2658 * hppa*64*-*-hpux11* target broken
2659 The debugger is unable to start a program and fails with the following
2660 error: "Error trying to get information about dynamic linker".
2661 The gdb-6.7 release is also affected.
2663 * GDB now supports the --enable-targets= configure option to allow
2664 building a single GDB executable that supports multiple remote
2665 target architectures.
2667 * GDB now supports debugging C and C++ programs which use the
2668 Decimal Floating Point extension. In addition, the PowerPC target
2669 now has a set of pseudo-registers to inspect decimal float values
2670 stored in two consecutive float registers.
2672 * The -break-insert MI command can optionally create pending
2675 * Improved support for debugging Ada
2676 Many improvements to the Ada language support have been made. These
2678 - Better support for Ada2005 interface types
2679 - Improved handling of arrays and slices in general
2680 - Better support for Taft-amendment types
2681 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2683 - Improved command completion in Ada
2686 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2691 set print frame-arguments (all|scalars|none)
2692 show print frame-arguments
2693 The value of this variable can be changed to control which argument
2694 values should be printed by the debugger when displaying a frame.
2699 Transfer files to and from a remote target, and delete remote files.
2706 Transfer files to and from a remote target, and delete remote files.
2708 * New remote packets
2715 Open, close, read, write, and delete files on the remote system.
2718 Attach to an existing process on the remote system, in extended-remote
2722 Run a new process on the remote system, in extended-remote mode.
2724 *** Changes in GDB 6.7
2726 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2727 bfd, libiberty and opcodes, as revealed by static analysis donated by
2728 Coverity, Inc. (http://scan.coverity.com).
2730 * When looking up multiply-defined global symbols, GDB will now prefer the
2731 symbol definition in the current shared library if it was built using the
2732 -Bsymbolic linker option.
2734 * When the Text User Interface (TUI) is not configured, GDB will now
2735 recognize the -tui command-line option and print a message that the TUI
2738 * The GDB remote stub, gdbserver, now has lower overhead for high
2739 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2741 * GDB for MIPS targets now autodetects whether a remote target provides
2742 32-bit or 64-bit register values.
2744 * Support for C++ member pointers has been improved.
2746 * GDB now understands XML target descriptions, which specify the
2747 target's overall architecture. GDB can read a description from
2748 a local file or over the remote serial protocol.
2750 * Vectors of single-byte data use a new integer type which is not
2751 automatically displayed as character or string data.
2753 * The /s format now works with the print command. It displays
2754 arrays of single-byte integers and pointers to single-byte integers
2757 * Target descriptions can now describe target-specific registers,
2758 for architectures which have implemented the support (currently
2759 only ARM, M68K, and MIPS).
2761 * GDB and the GDB remote stub, gdbserver, now support the XScale
2764 * The GDB remote stub, gdbserver, has been updated to support
2765 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2766 has been rewritten to use the standard GDB remote protocol.
2768 * GDB can now step into C++ functions which are called through thunks.
2770 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2772 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2773 layout. It also supports a TextSeg= and DataSeg= response when only
2774 segment base addresses (rather than offsets) are available.
2776 * The /i format now outputs any trailing branch delay slot instructions
2777 immediately following the last instruction within the count specified.
2779 * The GDB remote protocol "T" stop reply packet now supports a
2780 "library" response. Combined with the new "qXfer:libraries:read"
2781 packet, this response allows GDB to debug shared libraries on targets
2782 where the operating system manages the list of loaded libraries (e.g.
2783 Windows and SymbianOS).
2785 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2786 (DLLs) on Windows and Windows CE targets.
2788 * GDB now supports a faster verification that a .debug file matches its binary
2789 according to its build-id signature, if the signature is present.
2795 Enable or disable hardware flow control (RTS/CTS) on the serial port
2796 when debugging using remote targets.
2798 set mem inaccessible-by-default
2799 show mem inaccessible-by-default
2800 If the target supplies a memory map, for instance via the remote
2801 protocol's "qXfer:memory-map:read" packet, setting this variable
2802 prevents GDB from accessing memory outside the memory map. This
2803 is useful for targets with memory mapped registers or which react
2804 badly to accesses of unmapped address space.
2806 set breakpoint auto-hw
2807 show breakpoint auto-hw
2808 If the target supplies a memory map, for instance via the remote
2809 protocol's "qXfer:memory-map:read" packet, setting this variable
2810 lets GDB use hardware breakpoints automatically for memory regions
2811 where it can not use software breakpoints. This covers both the
2812 "break" command and internal breakpoints used for other commands
2813 including "next" and "finish".
2816 catch exception unhandled
2817 Stop the program execution when Ada exceptions are raised.
2820 Stop the program execution when an Ada assertion failed.
2824 Set an alternate system root for target files. This is a more
2825 general version of "set solib-absolute-prefix", which is now
2826 an alias to "set sysroot".
2829 Provide extended SPU facility status information. This set of
2830 commands is available only when debugging the Cell/B.E. SPU
2833 * New native configurations
2835 OpenBSD/sh sh*-*openbsd*
2838 unset tdesc filename
2840 Use the specified local file as an XML target description, and do
2841 not query the target for its built-in description.
2845 OpenBSD/sh sh*-*-openbsd*
2846 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2847 Toshiba Media Processor mep-elf
2849 * New remote packets
2852 Ignore the specified signals; pass them directly to the debugged program
2853 without stopping other threads or reporting them to GDB.
2855 qXfer:features:read:
2856 Read an XML target description from the target, which describes its
2861 Read or write contents of an spufs file on the target system. These
2862 packets are available only on the Cell/B.E. SPU architecture.
2864 qXfer:libraries:read:
2865 Report the loaded shared libraries. Combined with new "T" packet
2866 response, this packet allows GDB to debug shared libraries on
2867 targets where the operating system manages the list of loaded
2868 libraries (e.g. Windows and SymbianOS).
2872 Support for these obsolete configurations has been removed.
2880 i[34567]86-*-lynxos*
2881 i[34567]86-*-netware*
2882 i[34567]86-*-sco3.2v5*
2883 i[34567]86-*-sco3.2v4*
2885 i[34567]86-*-sysv4.2*
2888 i[34567]86-*-unixware2*
2889 i[34567]86-*-unixware*
2898 * Other removed features
2905 Various m68k-only ROM monitors.
2912 Various Renesas ROM monitors and debugging interfaces for SH and
2917 Support for a Macraigor serial interface to on-chip debugging.
2918 GDB does not directly support the newer parallel or USB
2923 A debug information format. The predecessor to DWARF 2 and
2924 DWARF 3, which are still supported.
2926 Support for the HP aCC compiler on HP-UX/PA-RISC
2928 SOM-encapsulated symbolic debugging information, automatic
2929 invocation of pxdb, and the aCC custom C++ ABI. This does not
2930 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2931 with aCC can still be debugged on an assembly level.
2933 MIPS ".pdr" sections
2935 A MIPS-specific format used to describe stack frame layout
2936 in debugging information.
2940 GDB could work with an older version of Guile to debug
2941 the interpreter and Scheme programs running in it.
2943 set mips stack-arg-size
2944 set mips saved-gpreg-size
2946 Use "set mips abi" to control parameter passing for MIPS.
2948 *** Changes in GDB 6.6
2953 Cell Broadband Engine SPU spu-elf
2955 * GDB can now be configured as a cross-debugger targeting native Windows
2956 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2957 running on a Windows system over TCP/IP to debug Windows programs.
2959 * The GDB remote stub, gdbserver, has been updated to support Windows and
2960 Cygwin debugging. Both single-threaded and multi-threaded programs are
2963 * The "set trust-readonly-sections" command works again. This command was
2964 broken in GDB 6.3, 6.4, and 6.5.
2966 * The "load" command now supports writing to flash memory, if the remote
2967 stub provides the required support.
2969 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2970 longer requires symbolic debug information (e.g. DWARF-2).
2975 unset substitute-path
2976 show substitute-path
2977 Manage a list of substitution rules that GDB uses to rewrite the name
2978 of the directories where the sources are located. This can be useful
2979 for instance when the sources were moved to a different location
2980 between compilation and debugging.
2984 Print each CLI command as it is executed. Each command is prefixed with
2985 a number of `+' symbols representing the nesting depth.
2986 The source command now has a `-v' option to enable the same feature.
2990 The ARM Demon monitor support (RDP protocol, "target rdp").
2992 Kernel Object Display, an embedded debugging feature which only worked with
2993 an obsolete version of Cisco IOS.
2995 The 'set download-write-size' and 'show download-write-size' commands.
2997 * New remote packets
3000 Tell a stub about GDB client features, and request remote target features.
3001 The first feature implemented is PacketSize, which allows the target to
3002 specify the size of packets it can handle - to minimize the number of
3003 packets required and improve performance when connected to a remote
3007 Fetch an OS auxilliary vector from the remote stub. This packet is a
3008 more efficient replacement for qPart:auxv:read.
3010 qXfer:memory-map:read:
3011 Fetch a memory map from the remote stub, including information about
3012 RAM, ROM, and flash memory devices.
3017 Erase and program a flash memory device.
3019 * Removed remote packets
3022 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3023 used it, and only gdbserver implemented it.
3025 *** Changes in GDB 6.5
3029 Renesas M32C/M16C m32c-elf
3031 Morpho Technologies ms1 ms1-elf
3035 init-if-undefined Initialize a convenience variable, but
3036 only if it doesn't already have a value.
3038 The following commands are presently only implemented for native GNU/Linux:
3040 checkpoint Save a snapshot of the program state.
3042 restart <n> Return the program state to a
3043 previously saved state.
3045 info checkpoints List currently saved checkpoints.
3047 delete-checkpoint <n> Delete a previously saved checkpoint.
3049 set|show detach-on-fork Tell gdb whether to detach from a newly
3050 forked process, or to keep debugging it.
3052 info forks List forks of the user program that
3053 are available to be debugged.
3055 fork <n> Switch to debugging one of several
3056 forks of the user program that are
3057 available to be debugged.
3059 delete-fork <n> Delete a fork from the list of forks
3060 that are available to be debugged (and
3061 kill the forked process).
3063 detach-fork <n> Delete a fork from the list of forks
3064 that are available to be debugged (and
3065 allow the process to continue).
3069 Morpho Technologies ms2 ms1-elf
3071 * Improved Windows host support
3073 GDB now builds as a cross debugger hosted on i686-mingw32, including
3074 native console support, and remote communications using either
3075 network sockets or serial ports.
3077 * Improved Modula-2 language support
3079 GDB can now print most types in the Modula-2 syntax. This includes:
3080 basic types, set types, record types, enumerated types, range types,
3081 pointer types and ARRAY types. Procedure var parameters are correctly
3082 printed and hexadecimal addresses and character constants are also
3083 written in the Modula-2 syntax. Best results can be obtained by using
3084 GNU Modula-2 together with the -gdwarf-2 command line option.
3088 The ARM rdi-share module.
3090 The Netware NLM debug server.
3092 *** Changes in GDB 6.4
3094 * New native configurations
3096 OpenBSD/arm arm*-*-openbsd*
3097 OpenBSD/mips64 mips64-*-openbsd*
3101 Morpho Technologies ms1 ms1-elf
3103 * New command line options
3105 --batch-silent As for --batch, but totally silent.
3106 --return-child-result The debugger will exist with the same value
3107 the child (debugged) program exited with.
3108 --eval-command COMMAND, -ex COMMAND
3109 Execute a single GDB CLI command. This may be
3110 specified multiple times and in conjunction
3111 with the --command (-x) option.
3113 * Deprecated commands removed
3115 The following commands, that were deprecated in 2000, have been
3119 set|show arm disassembly-flavor set|show arm disassembler
3120 othernames set arm disassembler
3121 set|show remotedebug set|show debug remote
3122 set|show archdebug set|show debug arch
3123 set|show eventdebug set|show debug event
3126 * New BSD user-level threads support
3128 It is now possible to debug programs using the user-level threads
3129 library on OpenBSD and FreeBSD. Currently supported (target)
3132 FreeBSD/amd64 x86_64-*-freebsd*
3133 FreeBSD/i386 i386-*-freebsd*
3134 OpenBSD/i386 i386-*-openbsd*
3136 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3137 are not yet supported.
3139 * New support for Matsushita MN10300 w/sim added
3140 (Work in progress). mn10300-elf.
3142 * REMOVED configurations and files
3144 VxWorks and the XDR protocol *-*-vxworks
3145 Motorola MCORE mcore-*-*
3146 National Semiconductor NS32000 ns32k-*-*
3148 * New "set print array-indexes" command
3150 After turning this setting "on", GDB prints the index of each element
3151 when displaying arrays. The default is "off" to preserve the previous
3154 * VAX floating point support
3156 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3158 * User-defined command support
3160 In addition to using $arg0..$arg9 for argument passing, it is now possible
3161 to use $argc to determine now many arguments have been passed. See the
3162 section on user-defined commands in the user manual for more information.
3164 *** Changes in GDB 6.3:
3166 * New command line option
3168 GDB now accepts -l followed by a number to set the timeout for remote
3171 * GDB works with GCC -feliminate-dwarf2-dups
3173 GDB now supports a more compact representation of DWARF-2 debug
3174 information using DW_FORM_ref_addr references. These are produced
3175 by GCC with the option -feliminate-dwarf2-dups and also by some
3176 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3177 to use -feliminate-dwarf2-dups.
3179 * Internationalization
3181 When supported by the host system, GDB will be built with
3182 internationalization (libintl). The task of marking up the sources is
3183 continued, we're looking forward to our first translation.
3187 Initial support for debugging programs compiled with the GNAT
3188 implementation of the Ada programming language has been integrated
3189 into GDB. In this release, support is limited to expression evaluation.
3191 * New native configurations
3193 GNU/Linux/m32r m32r-*-linux-gnu
3197 GDB's remote protocol now includes support for the 'p' packet. This
3198 packet is used to fetch individual registers from a remote inferior.
3200 * END-OF-LIFE registers[] compatibility module
3202 GDB's internal register infrastructure has been completely rewritten.
3203 The new infrastructure making possible the implementation of key new
3204 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3207 GDB 6.3 will be the last release to include the the registers[]
3208 compatibility module that allowed out-of-date configurations to
3209 continue to work. This change directly impacts the following
3219 powerpc bdm protocol
3221 Unless there is activity to revive these configurations, they will be
3222 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3224 * OBSOLETE configurations and files
3226 Configurations that have been declared obsolete in this release have
3227 been commented out. Unless there is activity to revive these
3228 configurations, the next release of GDB will have their sources
3229 permanently REMOVED.
3238 *** Changes in GDB 6.2.1:
3240 * MIPS `break main; run' gave an heuristic-fence-post warning
3242 When attempting to run even a simple program, a warning about
3243 heuristic-fence-post being hit would be reported. This problem has
3246 * MIPS IRIX 'long double' crashed GDB
3248 When examining a long double variable, GDB would get a segmentation
3249 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3250 IRIX long double values).
3254 A bug in the VAX stack code was causing problems with the "next"
3255 command. This problem has been fixed.
3257 *** Changes in GDB 6.2:
3259 * Fix for ``many threads''
3261 On GNU/Linux systems that use the NPTL threads library, a program
3262 rapidly creating and deleting threads would confuse GDB leading to the
3265 ptrace: No such process.
3266 thread_db_get_info: cannot get thread info: generic error
3268 This problem has been fixed.
3270 * "-async" and "-noasync" options removed.
3272 Support for the broken "-noasync" option has been removed (it caused
3275 * New ``start'' command.
3277 This command runs the program until the begining of the main procedure.
3279 * New BSD Kernel Data Access Library (libkvm) interface
3281 Using ``target kvm'' it is now possible to debug kernel core dumps and
3282 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3283 platforms. Currently supported (native-only) configurations are:
3285 FreeBSD/amd64 x86_64-*-freebsd*
3286 FreeBSD/i386 i?86-*-freebsd*
3287 NetBSD/i386 i?86-*-netbsd*
3288 NetBSD/m68k m68*-*-netbsd*
3289 NetBSD/sparc sparc-*-netbsd*
3290 OpenBSD/amd64 x86_64-*-openbsd*
3291 OpenBSD/i386 i?86-*-openbsd*
3292 OpenBSD/m68k m68*-openbsd*
3293 OpenBSD/sparc sparc-*-openbsd*
3295 * Signal trampoline code overhauled
3297 Many generic problems with GDB's signal handling code have been fixed.
3298 These include: backtraces through non-contiguous stacks; recognition
3299 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3300 call; backtrace through a signal trampoline; step into and out of
3301 signal handlers; and single-stepping in the signal trampoline.
3303 Please note that kernel bugs are a limiting factor here. These
3304 features have been shown to work on an s390 GNU/Linux system that
3305 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3307 * Cygwin support for DWARF 2 added.
3309 * New native configurations
3311 GNU/Linux/hppa hppa*-*-linux*
3312 OpenBSD/hppa hppa*-*-openbsd*
3313 OpenBSD/m68k m68*-*-openbsd*
3314 OpenBSD/m88k m88*-*-openbsd*
3315 OpenBSD/powerpc powerpc-*-openbsd*
3316 NetBSD/vax vax-*-netbsd*
3317 OpenBSD/vax vax-*-openbsd*
3319 * END-OF-LIFE frame compatibility module
3321 GDB's internal frame infrastructure has been completely rewritten.
3322 The new infrastructure making it possible to support key new features
3323 including DWARF 2 Call Frame Information. To aid in the task of
3324 migrating old configurations to this new infrastructure, a
3325 compatibility module, that allowed old configurations to continue to
3326 work, was also included.
3328 GDB 6.2 will be the last release to include this frame compatibility
3329 module. This change directly impacts the following configurations:
3339 Unless there is activity to revive these configurations, they will be
3340 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3342 * REMOVED configurations and files
3344 Sun 3, running SunOS 3 m68*-*-sunos3*
3345 Sun 3, running SunOS 4 m68*-*-sunos4*
3346 Sun 2, running SunOS 3 m68000-*-sunos3*
3347 Sun 2, running SunOS 4 m68000-*-sunos4*
3348 Motorola 680x0 running LynxOS m68*-*-lynxos*
3349 AT&T 3b1/Unix pc m68*-att-*
3350 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3351 decstation mips-dec-* mips-little-*
3352 riscos mips-*-riscos* mips-*-sysv*
3353 sonymips mips-sony-*
3354 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3356 *** Changes in GDB 6.1.1:
3358 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3360 The TUI (Text-mode User Interface) is now built as part of a default
3361 GDB configuration. It is enabled by either selecting the TUI with the
3362 command line option "-i=tui" or by running the separate "gdbtui"
3363 program. For more information on the TUI, see the manual "Debugging
3366 * Pending breakpoint support (also included in GDB 6.1)
3368 Support has been added to allow you to specify breakpoints in shared
3369 libraries that have not yet been loaded. If a breakpoint location
3370 cannot be found, and the "breakpoint pending" option is set to auto,
3371 GDB queries you if you wish to make the breakpoint pending on a future
3372 shared-library load. If and when GDB resolves the breakpoint symbol,
3373 the pending breakpoint is removed as one or more regular breakpoints
3376 Pending breakpoints are very useful for GCJ Java debugging.
3378 * Fixed ISO-C build problems
3380 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3381 non ISO-C code that stopped them being built using a more strict ISO-C
3382 compiler (e.g., IBM's C compiler).
3384 * Fixed build problem on IRIX 5
3386 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3387 wasn't able to compile compile on an IRIX 5 system.
3389 * Added execute permission to gdb/gdbserver/configure
3391 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3392 permission. This bug would cause configure to fail on a number of
3393 systems (Solaris, IRIX). Ref: server/519.
3395 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3397 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3398 has been updated to use constant array sizes.
3400 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3402 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3403 its generated DWARF Call Frame Info. This encoding was causing GDB to
3404 panic, that panic has been fixed. Ref: gdb/1628.
3406 * Fixed a problem when examining parameters in shared library code.
3408 When examining parameters in optimized shared library code generated
3409 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3410 not available''. GDB now correctly displays the variable's value.
3412 *** Changes in GDB 6.1:
3414 * Removed --with-mmalloc
3416 Support for the mmalloc memory manager has been removed, as it
3417 conflicted with the internal gdb byte cache.
3419 * Changes in AMD64 configurations
3421 The AMD64 target now includes the %cs and %ss registers. As a result
3422 the AMD64 remote protocol has changed; this affects the floating-point
3423 and SSE registers. If you rely on those registers for your debugging,
3424 you should upgrade gdbserver on the remote side.
3426 * Revised SPARC target
3428 The SPARC target has been completely revised, incorporating the
3429 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3430 support for LynxOS and SunOS 4 has been dropped. Calling functions
3431 from within GDB on operating systems with a non-executable stack
3432 (Solaris, OpenBSD) now works.
3436 GDB has a new C++ demangler which does a better job on the mangled
3437 names generated by current versions of g++. It also runs faster, so
3438 with this and other changes gdb should now start faster on large C++
3441 * DWARF 2 Location Expressions
3443 GDB support for location expressions has been extended to support function
3444 arguments and frame bases. Older versions of GDB could crash when they
3447 * C++ nested types and namespaces
3449 GDB's support for nested types and namespaces in C++ has been
3450 improved, especially if you use the DWARF 2 debugging format. (This
3451 is the default for recent versions of GCC on most platforms.)
3452 Specifically, if you have a class "Inner" defined within a class or
3453 namespace "Outer", then GDB realizes that the class's name is
3454 "Outer::Inner", not simply "Inner". This should greatly reduce the
3455 frequency of complaints about not finding RTTI symbols. In addition,
3456 if you are stopped at inside of a function defined within a namespace,
3457 GDB modifies its name lookup accordingly.
3459 * New native configurations
3461 NetBSD/amd64 x86_64-*-netbsd*
3462 OpenBSD/amd64 x86_64-*-openbsd*
3463 OpenBSD/alpha alpha*-*-openbsd*
3464 OpenBSD/sparc sparc-*-openbsd*
3465 OpenBSD/sparc64 sparc64-*-openbsd*
3467 * New debugging protocols
3469 M32R with SDI protocol m32r-*-elf*
3471 * "set prompt-escape-char" command deleted.
3473 The command "set prompt-escape-char" has been deleted. This command,
3474 and its very obscure effet on GDB's prompt, was never documented,
3475 tested, nor mentioned in the NEWS file.
3477 * OBSOLETE configurations and files
3479 Configurations that have been declared obsolete in this release have
3480 been commented out. Unless there is activity to revive these
3481 configurations, the next release of GDB will have their sources
3482 permanently REMOVED.
3484 Sun 3, running SunOS 3 m68*-*-sunos3*
3485 Sun 3, running SunOS 4 m68*-*-sunos4*
3486 Sun 2, running SunOS 3 m68000-*-sunos3*
3487 Sun 2, running SunOS 4 m68000-*-sunos4*
3488 Motorola 680x0 running LynxOS m68*-*-lynxos*
3489 AT&T 3b1/Unix pc m68*-att-*
3490 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3491 decstation mips-dec-* mips-little-*
3492 riscos mips-*-riscos* mips-*-sysv*
3493 sonymips mips-sony-*
3494 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3496 * REMOVED configurations and files
3498 SGI Irix-4.x mips-sgi-irix4 or iris4
3499 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3500 Z8000 simulator z8k-zilog-none or z8ksim
3501 Matsushita MN10200 w/simulator mn10200-*-*
3502 H8/500 simulator h8500-hitachi-hms or h8500hms
3503 HP/PA running BSD hppa*-*-bsd*
3504 HP/PA running OSF/1 hppa*-*-osf*
3505 HP/PA Pro target hppa*-*-pro*
3506 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3507 386BSD i[3456]86-*-bsd*
3508 Sequent family i[3456]86-sequent-sysv4*
3509 i[3456]86-sequent-sysv*
3510 i[3456]86-sequent-bsd*
3511 SPARC running LynxOS sparc-*-lynxos*
3512 SPARC running SunOS 4 sparc-*-sunos4*
3513 Tsqware Sparclet sparclet-*-*
3514 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3516 *** Changes in GDB 6.0:
3520 Support for debugging the Objective-C programming language has been
3521 integrated into GDB.
3523 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3525 DWARF 2's Call Frame Information makes available compiler generated
3526 information that more exactly describes the program's run-time stack.
3527 By using this information, GDB is able to provide more robust stack
3530 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3531 have been updated to use a new backtrace mechanism which includes
3532 DWARF 2 CFI support.
3536 GDB's remote protocol has been extended to include support for hosted
3537 file I/O (where the remote target uses GDB's file system). See GDB's
3538 remote protocol documentation for details.
3540 * All targets using the new architecture framework.
3542 All of GDB's targets have been updated to use the new internal
3543 architecture framework. The way is now open for future GDB releases
3544 to include cross-architecture native debugging support (i386 on amd64,
3547 * GNU/Linux's Thread Local Storage (TLS)
3549 GDB now includes support for for the GNU/Linux implementation of
3550 per-thread variables.
3552 * GNU/Linux's Native POSIX Thread Library (NPTL)
3554 GDB's thread code has been updated to work with either the new
3555 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3557 * Separate debug info.
3559 GDB, in conjunction with BINUTILS, now supports a mechanism for
3560 automatically loading debug information from a separate file. Instead
3561 of shipping full debug and non-debug versions of system libraries,
3562 system integrators can now instead ship just the stripped libraries
3563 and optional debug files.
3565 * DWARF 2 Location Expressions
3567 DWARF 2 Location Expressions allow the compiler to more completely
3568 describe the location of variables (even in optimized code) to the
3571 GDB now includes preliminary support for location expressions (support
3572 for DW_OP_piece is still missing).
3576 A number of long standing bugs that caused GDB to die while starting a
3577 Java application have been fixed. GDB's Java support is now
3578 considered "useable".
3580 * GNU/Linux support for fork, vfork, and exec.
3582 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3583 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3586 * GDB supports logging output to a file
3588 There are two new commands, "set logging" and "show logging", which can be
3589 used to capture GDB's output to a file.
3591 * The meaning of "detach" has changed for gdbserver
3593 The "detach" command will now resume the application, as documented. To
3594 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3597 * d10v, m68hc11 `regs' command deprecated
3599 The `info registers' command has been updated so that it displays the
3600 registers using a format identical to the old `regs' command.
3604 A new command, "maint set profile on/off", has been added. This command can
3605 be used to enable or disable profiling while running GDB, to profile a
3606 session or a set of commands. In addition there is a new configure switch,
3607 "--enable-profiling", which will cause GDB to be compiled with profiling
3608 data, for more informative profiling results.
3610 * Default MI syntax changed to "mi2".
3612 The default MI (machine interface) syntax, enabled by the command line
3613 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3614 "mi1", can be enabled by specifying the option "-i=mi1".
3616 Support for the original "mi0" syntax (included in GDB 5.0) has been
3619 Fix for gdb/192: removed extraneous space when displaying frame level.
3620 Fix for gdb/672: update changelist is now output in mi list format.
3621 Fix for gdb/702: a -var-assign that updates the value now shows up
3622 in a subsequent -var-update.
3624 * New native configurations.
3626 FreeBSD/amd64 x86_64-*-freebsd*
3628 * Multi-arched targets.
3630 HP/PA HPUX11 hppa*-*-hpux*
3631 Renesas M32R/D w/simulator m32r-*-elf*
3633 * OBSOLETE configurations and files
3635 Configurations that have been declared obsolete in this release have
3636 been commented out. Unless there is activity to revive these
3637 configurations, the next release of GDB will have their sources
3638 permanently REMOVED.
3640 Z8000 simulator z8k-zilog-none or z8ksim
3641 Matsushita MN10200 w/simulator mn10200-*-*
3642 H8/500 simulator h8500-hitachi-hms or h8500hms
3643 HP/PA running BSD hppa*-*-bsd*
3644 HP/PA running OSF/1 hppa*-*-osf*
3645 HP/PA Pro target hppa*-*-pro*
3646 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3647 Sequent family i[3456]86-sequent-sysv4*
3648 i[3456]86-sequent-sysv*
3649 i[3456]86-sequent-bsd*
3650 Tsqware Sparclet sparclet-*-*
3651 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3653 * REMOVED configurations and files
3656 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3657 IBM AIX PS/2 i[3456]86-*-aix
3658 i386 running Mach 3.0 i[3456]86-*-mach3*
3659 i386 running Mach i[3456]86-*-mach*
3660 i386 running OSF/1 i[3456]86-*osf1mk*
3661 HP/Apollo 68k Family m68*-apollo*-sysv*,
3663 m68*-hp-bsd*, m68*-hp-hpux*
3664 Argonaut Risc Chip (ARC) arc-*-*
3665 Mitsubishi D30V d30v-*-*
3666 Fujitsu FR30 fr30-*-elf*
3667 OS/9000 i[34]86-*-os9k
3668 I960 with MON960 i960-*-coff
3670 * MIPS $fp behavior changed
3672 The convenience variable $fp, for the MIPS, now consistently returns
3673 the address of the current frame's base. Previously, depending on the
3674 context, $fp could refer to either $sp or the current frame's base
3675 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3676 The GNU Source-Level Debugger''.
3678 *** Changes in GDB 5.3:
3680 * GNU/Linux shared library multi-threaded performance improved.
3682 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3683 `/proc', in preference to `ptrace' for memory reads. This may result
3684 in an improvement in the start-up time of multi-threaded, shared
3685 library applications when run under GDB. One GDB user writes: ``loads
3686 shared libs like mad''.
3688 * ``gdbserver'' now supports multi-threaded applications on some targets
3690 Support for debugging multi-threaded applications which use
3691 the GNU/Linux LinuxThreads package has been added for
3692 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3693 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3695 * GDB now supports C/C++ preprocessor macros.
3697 GDB now expands preprocessor macro invocations in C/C++ expressions,
3698 and provides various commands for showing macro definitions and how
3701 The new command `macro expand EXPRESSION' expands any macro
3702 invocations in expression, and shows the result.
3704 The new command `show macro MACRO-NAME' shows the definition of the
3705 macro named MACRO-NAME, and where it was defined.
3707 Most compilers don't include information about macros in the debugging
3708 information by default. In GCC 3.1, for example, you need to compile
3709 your program with the options `-gdwarf-2 -g3'. If the macro
3710 information is present in the executable, GDB will read it.
3712 * Multi-arched targets.
3714 DEC Alpha (partial) alpha*-*-*
3715 DEC VAX (partial) vax-*-*
3717 National Semiconductor NS32000 (partial) ns32k-*-*
3718 Motorola 68000 (partial) m68k-*-*
3719 Motorola MCORE mcore-*-*
3723 Fujitsu FRV architecture added by Red Hat frv*-*-*
3726 * New native configurations
3728 Alpha NetBSD alpha*-*-netbsd*
3729 SH NetBSD sh*-*-netbsdelf*
3730 MIPS NetBSD mips*-*-netbsd*
3731 UltraSPARC NetBSD sparc64-*-netbsd*
3733 * OBSOLETE configurations and files
3735 Configurations that have been declared obsolete in this release have
3736 been commented out. Unless there is activity to revive these
3737 configurations, the next release of GDB will have their sources
3738 permanently REMOVED.
3740 Mitsubishi D30V d30v-*-*
3741 OS/9000 i[34]86-*-os9k
3742 IBM AIX PS/2 i[3456]86-*-aix
3743 Fujitsu FR30 fr30-*-elf*
3744 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3745 Argonaut Risc Chip (ARC) arc-*-*
3746 i386 running Mach 3.0 i[3456]86-*-mach3*
3747 i386 running Mach i[3456]86-*-mach*
3748 i386 running OSF/1 i[3456]86-*osf1mk*
3749 HP/Apollo 68k Family m68*-apollo*-sysv*,
3751 m68*-hp-bsd*, m68*-hp-hpux*
3752 I960 with MON960 i960-*-coff
3754 * OBSOLETE languages
3756 CHILL, a Pascal like language used by telecommunications companies.
3758 * REMOVED configurations and files
3760 AMD 29k family via UDI a29k-amd-udi, udi29k
3761 A29K VxWorks a29k-*-vxworks
3762 AMD 29000 embedded, using EBMON a29k-none-none
3763 AMD 29000 embedded with COFF a29k-none-coff
3764 AMD 29000 embedded with a.out a29k-none-aout
3766 testsuite/gdb.hp/gdb.threads-hp/ directory
3768 * New command "set max-user-call-depth <nnn>"
3770 This command allows the user to limit the call depth of user-defined
3771 commands. The default is 1024.
3773 * Changes in FreeBSD/i386 native debugging.
3775 Support for the "generate-core-file" has been added.
3777 * New commands "dump", "append", and "restore".
3779 These commands allow data to be copied from target memory
3780 to a bfd-format or binary file (dump and append), and back
3781 from a file into memory (restore).
3783 * Improved "next/step" support on multi-processor Alpha Tru64.
3785 The previous single-step mechanism could cause unpredictable problems,
3786 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3787 of a software single-step mechanism prevents this.
3789 *** Changes in GDB 5.2.1:
3797 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3798 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3799 Fix, by Joel Brobecker imported from mainline.
3801 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3802 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3803 Fix, by Fred Fish, imported from mainline.
3805 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3806 Surprisingly enough, it works now.
3807 By Michal Ludvig, imported from mainline.
3809 i386 hardware watchpoint support:
3810 avoid misses on second run for some targets.
3811 By Pierre Muller, imported from mainline.
3813 *** Changes in GDB 5.2:
3815 * New command "set trust-readonly-sections on[off]".
3817 This command is a hint that tells gdb that read-only sections
3818 really are read-only (ie. that their contents will not change).
3819 In this mode, gdb will go to the object file rather than the
3820 target to read memory from read-only sections (such as ".text").
3821 This can be a significant performance improvement on some
3822 (notably embedded) targets.
3824 * New command "generate-core-file" (or "gcore").
3826 This new gdb command allows the user to drop a core file of the child
3827 process state at any time. So far it's been implemented only for
3828 GNU/Linux and Solaris, but should be relatively easily ported to other
3829 hosts. Argument is core file name (defaults to core.<pid>).
3831 * New command line option
3833 GDB now accepts --pid or -p followed by a process id.
3835 * Change in command line behavior -- corefiles vs. process ids.
3837 There is a subtle behavior in the way in which GDB handles
3838 command line arguments. The first non-flag argument is always
3839 a program to debug, but the second non-flag argument may either
3840 be a corefile or a process id. Previously, GDB would attempt to
3841 open the second argument as a corefile, and if that failed, would
3842 issue a superfluous error message and then attempt to attach it as
3843 a process. Now, if the second argument begins with a non-digit,
3844 it will be treated as a corefile. If it begins with a digit,
3845 GDB will attempt to attach it as a process, and if no such process
3846 is found, will then attempt to open it as a corefile.
3848 * Changes in ARM configurations.
3850 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3851 configuration is fully multi-arch.
3853 * New native configurations
3855 ARM NetBSD arm*-*-netbsd*
3856 x86 OpenBSD i[3456]86-*-openbsd*
3857 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3858 Sparc64 running FreeBSD sparc64-*-freebsd*
3862 Sanyo XStormy16 xstormy16-elf
3864 * OBSOLETE configurations and files
3866 Configurations that have been declared obsolete in this release have
3867 been commented out. Unless there is activity to revive these
3868 configurations, the next release of GDB will have their sources
3869 permanently REMOVED.
3871 AMD 29k family via UDI a29k-amd-udi, udi29k
3872 A29K VxWorks a29k-*-vxworks
3873 AMD 29000 embedded, using EBMON a29k-none-none
3874 AMD 29000 embedded with COFF a29k-none-coff
3875 AMD 29000 embedded with a.out a29k-none-aout
3877 testsuite/gdb.hp/gdb.threads-hp/ directory
3879 * REMOVED configurations and files
3881 TI TMS320C80 tic80-*-*
3883 PowerPC Solaris powerpcle-*-solaris*
3884 PowerPC Windows NT powerpcle-*-cygwin32
3885 PowerPC Netware powerpc-*-netware*
3886 Harris/CXUX m88k m88*-harris-cxux*
3887 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3888 ns32k-utek-sysv* ns32k-utek-*
3889 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3890 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3891 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3892 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3893 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3895 * Changes to command line processing
3897 The new `--args' feature can be used to specify command-line arguments
3898 for the inferior from gdb's command line.
3900 * Changes to key bindings
3902 There is a new `operate-and-get-next' function bound to `C-o'.
3904 *** Changes in GDB 5.1.1
3906 Fix compile problem on DJGPP.
3908 Fix a problem with floating-point registers on the i386 being
3911 Fix to stop GDB crashing on .debug_str debug info.
3913 Numerous documentation fixes.
3915 Numerous testsuite fixes.
3917 *** Changes in GDB 5.1:
3919 * New native configurations
3921 Alpha FreeBSD alpha*-*-freebsd*
3922 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3923 MIPS GNU/Linux mips*-*-linux*
3924 MIPS SGI Irix 6.x mips*-sgi-irix6*
3925 ia64 AIX ia64-*-aix*
3926 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3930 Motorola 68HC11 and 68HC12 m68hc11-elf
3932 UltraSparc running GNU/Linux sparc64-*-linux*
3934 * OBSOLETE configurations and files
3936 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3937 Harris/CXUX m88k m88*-harris-cxux*
3938 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3939 ns32k-utek-sysv* ns32k-utek-*
3940 TI TMS320C80 tic80-*-*
3942 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3943 PowerPC Solaris powerpcle-*-solaris*
3944 PowerPC Windows NT powerpcle-*-cygwin32
3945 PowerPC Netware powerpc-*-netware*
3946 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3947 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3948 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3949 Apple Macintosh (MPW) host N/A
3951 stuff.c (Program to stuff files into a specially prepared space in kdb)
3952 kdb-start.c (Main loop for the standalone kernel debugger)
3954 Configurations that have been declared obsolete in this release have
3955 been commented out. Unless there is activity to revive these
3956 configurations, the next release of GDB will have their sources
3957 permanently REMOVED.
3959 * REMOVED configurations and files
3961 Altos 3068 m68*-altos-*
3962 Convex c1-*-*, c2-*-*
3964 ARM RISCix arm-*-* (as host)
3968 * GDB has been converted to ISO C.
3970 GDB's source code has been converted to ISO C. In particular, the
3971 sources are fully protoized, and rely on standard headers being
3976 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3978 * The MI enabled by default.
3980 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3981 revised and enabled by default. Packages which use GDB as a debugging
3982 engine behind a UI or another front end are encouraged to switch to
3983 using the GDB/MI interface, instead of the old annotations interface
3984 which is now deprecated.
3986 * Support for debugging Pascal programs.
3988 GDB now includes support for debugging Pascal programs. The following
3989 main features are supported:
3991 - Pascal-specific data types such as sets;
3993 - automatic recognition of Pascal sources based on file-name
3996 - Pascal-style display of data types, variables, and functions;
3998 - a Pascal expression parser.
4000 However, some important features are not yet supported.
4002 - Pascal string operations are not supported at all;
4004 - there are some problems with boolean types;
4006 - Pascal type hexadecimal constants are not supported
4007 because they conflict with the internal variables format;
4009 - support for Pascal objects and classes is not full yet;
4011 - unlike Pascal, GDB is case-sensitive for symbol names.
4013 * Changes in completion.
4015 Commands such as `shell', `run' and `set args', which pass arguments
4016 to inferior programs, now complete on file names, similar to what
4017 users expect at the shell prompt.
4019 Commands which accept locations, such as `disassemble', `print',
4020 `breakpoint', `until', etc. now complete on filenames as well as
4021 program symbols. Thus, if you type "break foob TAB", and the source
4022 files linked into the programs include `foobar.c', that file name will
4023 be one of the candidates for completion. However, file names are not
4024 considered for completion after you typed a colon that delimits a file
4025 name from a name of a function in that file, as in "break foo.c:bar".
4027 `set demangle-style' completes on available demangling styles.
4029 * New platform-independent commands:
4031 It is now possible to define a post-hook for a command as well as a
4032 hook that runs before the command. For more details, see the
4033 documentation of `hookpost' in the GDB manual.
4035 * Changes in GNU/Linux native debugging.
4037 Support for debugging multi-threaded programs has been completely
4038 revised for all platforms except m68k and sparc. You can now debug as
4039 many threads as your system allows you to have.
4041 Attach/detach is supported for multi-threaded programs.
4043 Support for SSE registers was added for x86. This doesn't work for
4044 multi-threaded programs though.
4046 * Changes in MIPS configurations.
4048 Multi-arch support is enabled for all MIPS configurations.
4050 GDB can now be built as native debugger on SGI Irix 6.x systems for
4051 debugging n32 executables. (Debugging 64-bit executables is not yet
4054 * Unified support for hardware watchpoints in all x86 configurations.
4056 Most (if not all) native x86 configurations support hardware-assisted
4057 breakpoints and watchpoints in a unified manner. This support
4058 implements debug register sharing between watchpoints, which allows to
4059 put a virtually infinite number of watchpoints on the same address,
4060 and also supports watching regions up to 16 bytes with several debug
4063 The new maintenance command `maintenance show-debug-regs' toggles
4064 debugging print-outs in functions that insert, remove, and test
4065 watchpoints and hardware breakpoints.
4067 * Changes in the DJGPP native configuration.
4069 New command ``info dos sysinfo'' displays assorted information about
4070 the CPU, OS, memory, and DPMI server.
4072 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4073 display information about segment descriptors stored in GDT, LDT, and
4076 New commands ``info dos pde'' and ``info dos pte'' display entries
4077 from Page Directory and Page Tables (for now works with CWSDPMI only).
4078 New command ``info dos address-pte'' displays the Page Table entry for
4079 a given linear address.
4081 GDB can now pass command lines longer than 126 characters to the
4082 program being debugged (requires an update to the libdbg.a library
4083 which is part of the DJGPP development kit).
4085 DWARF2 debug info is now supported.
4087 It is now possible to `step' and `next' through calls to `longjmp'.
4089 * Changes in documentation.
4091 All GDB documentation was converted to GFDL, the GNU Free
4092 Documentation License.
4094 Tracepoints-related commands are now fully documented in the GDB
4097 TUI, the Text-mode User Interface, is now documented in the manual.
4099 Tracepoints-related commands are now fully documented in the GDB
4102 The "GDB Internals" manual now has an index. It also includes
4103 documentation of `ui_out' functions, GDB coding standards, x86
4104 hardware watchpoints, and memory region attributes.
4106 * GDB's version number moved to ``version.in''
4108 The Makefile variable VERSION has been replaced by the file
4109 ``version.in''. People creating GDB distributions should update the
4110 contents of this file.
4114 GUD support is now a standard part of the EMACS distribution.
4116 *** Changes in GDB 5.0:
4118 * Improved support for debugging FP programs on x86 targets
4120 Unified and much-improved support for debugging floating-point
4121 programs on all x86 targets. In particular, ``info float'' now
4122 displays the FP registers in the same format on all x86 targets, with
4123 greater level of detail.
4125 * Improvements and bugfixes in hardware-assisted watchpoints
4127 It is now possible to watch array elements, struct members, and
4128 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4129 on x86 targets no longer erroneously trigger when the address is
4132 * Improvements in the native DJGPP version of GDB
4134 The distribution now includes all the scripts and auxiliary files
4135 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4136 machines ``out of the box''.
4138 The DJGPP version can now debug programs that use signals. It is
4139 possible to catch signals that happened in the debuggee, deliver
4140 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4141 would kill the program being debugged.) Programs that hook hardware
4142 interrupts (keyboard, timer, etc.) can also be debugged.
4144 It is now possible to debug DJGPP programs that redirect their
4145 standard handles or switch them to raw (as opposed to cooked) mode, or
4146 even close them. The command ``run < foo > bar'' works as expected,
4147 and ``info terminal'' reports useful information about the debuggee's
4148 terminal, including raw/cooked mode, redirection, etc.
4150 The DJGPP version now uses termios functions for console I/O, which
4151 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4154 DOS-style file names with drive letters are now fully supported by
4157 It is now possible to debug DJGPP programs that switch their working
4158 directory. It is also possible to rerun the debuggee any number of
4159 times without restarting GDB; thus, you can use the same setup,
4160 breakpoints, etc. for many debugging sessions.
4162 * New native configurations
4164 ARM GNU/Linux arm*-*-linux*
4165 PowerPC GNU/Linux powerpc-*-linux*
4169 Motorola MCore mcore-*-*
4170 x86 VxWorks i[3456]86-*-vxworks*
4171 PowerPC VxWorks powerpc-*-vxworks*
4172 TI TMS320C80 tic80-*-*
4174 * OBSOLETE configurations
4176 Altos 3068 m68*-altos-*
4177 Convex c1-*-*, c2-*-*
4179 ARM RISCix arm-*-* (as host)
4182 Configurations that have been declared obsolete will be commented out,
4183 but the code will be left in place. If there is no activity to revive
4184 these configurations before the next release of GDB, the sources will
4185 be permanently REMOVED.
4187 * Gould support removed
4189 Support for the Gould PowerNode and NP1 has been removed.
4191 * New features for SVR4
4193 On SVR4 native platforms (such as Solaris), if you attach to a process
4194 without first loading a symbol file, GDB will now attempt to locate and
4195 load symbols from the running process's executable file.
4197 * Many C++ enhancements
4199 C++ support has been greatly improved. Overload resolution now works properly
4200 in almost all cases. RTTI support is on the way.
4202 * Remote targets can connect to a sub-program
4204 A popen(3) style serial-device has been added. This device starts a
4205 sub-process (such as a stand-alone simulator) and then communicates
4206 with that. The sub-program to run is specified using the syntax
4207 ``|<program> <args>'' vis:
4209 (gdb) set remotedebug 1
4210 (gdb) target extended-remote |mn10300-elf-sim program-args
4212 * MIPS 64 remote protocol
4214 A long standing bug in the mips64 remote protocol where by GDB
4215 expected certain 32 bit registers (ex SR) to be transfered as 32
4216 instead of 64 bits has been fixed.
4218 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4219 added to provide backward compatibility with older versions of GDB.
4221 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4223 The command ``set remotebinarydownload'' command has been replaced by
4224 ``set remote X-packet''. Other commands in ``set remote'' family
4225 include ``set remote P-packet''.
4227 * Breakpoint commands accept ranges.
4229 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4230 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4231 ``tracepoint passcount'' also accepts a range of tracepoints.
4233 * ``apropos'' command added.
4235 The ``apropos'' command searches through command names and
4236 documentation strings, printing out matches, making it much easier to
4237 try to find a command that does what you are looking for.
4241 A new machine oriented interface (MI) has been added to GDB. This
4242 interface is designed for debug environments running GDB as a separate
4243 process. This is part of the long term libGDB project. See the
4244 "GDB/MI" chapter of the GDB manual for further information. It can be
4245 enabled by configuring with:
4247 .../configure --enable-gdbmi
4249 *** Changes in GDB-4.18:
4251 * New native configurations
4253 HP-UX 10.20 hppa*-*-hpux10.20
4254 HP-UX 11.x hppa*-*-hpux11.0*
4255 M68K GNU/Linux m68*-*-linux*
4259 Fujitsu FR30 fr30-*-elf*
4260 Intel StrongARM strongarm-*-*
4261 Mitsubishi D30V d30v-*-*
4263 * OBSOLETE configurations
4265 Gould PowerNode, NP1 np1-*-*, pn-*-*
4267 Configurations that have been declared obsolete will be commented out,
4268 but the code will be left in place. If there is no activity to revive
4269 these configurations before the next release of GDB, the sources will
4270 be permanently REMOVED.
4274 As a compatibility experiment, GDB's source files buildsym.h and
4275 buildsym.c have been converted to pure standard C, no longer
4276 containing any K&R compatibility code. We believe that all systems in
4277 use today either come with a standard C compiler, or have a GCC port
4278 available. If this is not true, please report the affected
4279 configuration to bug-gdb@gnu.org immediately. See the README file for
4280 information about getting a standard C compiler if you don't have one
4285 GDB now uses readline 2.2.
4287 * set extension-language
4289 You can now control the mapping between filename extensions and source
4290 languages by using the `set extension-language' command. For instance,
4291 you can ask GDB to treat .c files as C++ by saying
4292 set extension-language .c c++
4293 The command `info extensions' lists all of the recognized extensions
4294 and their associated languages.
4296 * Setting processor type for PowerPC and RS/6000
4298 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4299 you can use the `set processor' command to specify what variant of the
4300 PowerPC family you are debugging. The command
4304 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4305 following PowerPC and RS6000 variants:
4307 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4308 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4310 403GC IBM PowerPC 403GC
4311 505 Motorola PowerPC 505
4312 860 Motorola PowerPC 860 or 850
4313 601 Motorola PowerPC 601
4314 602 Motorola PowerPC 602
4315 603 Motorola/IBM PowerPC 603 or 603e
4316 604 Motorola PowerPC 604 or 604e
4317 750 Motorola/IBM PowerPC 750 or 750
4319 At the moment, this command just tells GDB what to name the
4320 special-purpose processor registers. Since almost all the affected
4321 registers are inaccessible to user-level programs, this command is
4322 only useful for remote debugging in its present form.
4326 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4327 more extensive support for HP-UX. Added features include shared
4328 library support, kernel threads and hardware watchpoints for 11.00,
4329 support for HP's ANSI C and C++ compilers, and a compatibility mode
4330 for xdb and dbx commands.
4334 HP's donation includes the new concept of catchpoints, which is a
4335 generalization of the old catch command. On HP-UX, it is now possible
4336 to catch exec, fork, and vfork, as well as library loading.
4338 This means that the existing catch command has changed; its first
4339 argument now specifies the type of catch to be set up. See the
4340 output of "help catch" for a list of catchpoint types.
4342 * Debugging across forks
4344 On HP-UX, you can choose which process to debug when a fork() happens
4349 HP has donated a curses-based terminal user interface (TUI). To get
4350 it, build with --enable-tui. Although this can be enabled for any
4351 configuration, at present it only works for native HP debugging.
4353 * GDB remote protocol additions
4355 A new protocol packet 'X' that writes binary data is now available.
4356 Default behavior is to try 'X', then drop back to 'M' if the stub
4357 fails to respond. The settable variable `remotebinarydownload'
4358 allows explicit control over the use of 'X'.
4360 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4361 full 64-bit address. The command
4363 set remoteaddresssize 32
4365 can be used to revert to the old behaviour. For existing remote stubs
4366 the change should not be noticed, as the additional address information
4369 In order to assist in debugging stubs, you may use the maintenance
4370 command `packet' to send any text string to the stub. For instance,
4372 maint packet heythere
4374 sends the packet "$heythere#<checksum>". Note that it is very easy to
4375 disrupt a debugging session by sending the wrong packet at the wrong
4378 The compare-sections command allows you to compare section data on the
4379 target to what is in the executable file without uploading or
4380 downloading, by comparing CRC checksums.
4382 * Tracing can collect general expressions
4384 You may now collect general expressions at tracepoints. This requires
4385 further additions to the target-side stub; see tracepoint.c and
4386 doc/agentexpr.texi for further details.
4388 * mask-address variable for Mips
4390 For Mips targets, you may control the zeroing of the upper 32 bits of
4391 a 64-bit address by entering `set mask-address on'. This is mainly
4392 of interest to users of embedded R4xxx and R5xxx processors.
4394 * Higher serial baud rates
4396 GDB's serial code now allows you to specify baud rates 57600, 115200,
4397 230400, and 460800 baud. (Note that your host system may not be able
4398 to achieve all of these rates.)
4402 The i960 configuration now includes an initial implementation of a
4403 builtin simulator, contributed by Jim Wilson.
4406 *** Changes in GDB-4.17:
4408 * New native configurations
4410 Alpha GNU/Linux alpha*-*-linux*
4411 Unixware 2.x i[3456]86-unixware2*
4412 Irix 6.x mips*-sgi-irix6*
4413 PowerPC GNU/Linux powerpc-*-linux*
4414 PowerPC Solaris powerpcle-*-solaris*
4415 Sparc GNU/Linux sparc-*-linux*
4416 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4420 Argonaut Risc Chip (ARC) arc-*-*
4421 Hitachi H8/300S h8300*-*-*
4422 Matsushita MN10200 w/simulator mn10200-*-*
4423 Matsushita MN10300 w/simulator mn10300-*-*
4424 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4425 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4426 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4427 Mitsubishi D10V w/simulator d10v-*-*
4428 Mitsubishi M32R/D w/simulator m32r-*-elf*
4429 Tsqware Sparclet sparclet-*-*
4430 NEC V850 w/simulator v850-*-*
4432 * New debugging protocols
4434 ARM with RDI protocol arm*-*-*
4435 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4436 DDB and LSI variants of PMON protocol mips*-*-*
4437 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4438 PowerPC with SDS protocol powerpc{,le}-*-eabi
4439 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4443 All configurations can now understand and use the DWARF 2 debugging
4444 format. The choice is automatic, if the symbol file contains DWARF 2
4449 GDB now includes basic Java language support. This support is
4450 only useful with Java compilers that produce native machine code.
4452 * solib-absolute-prefix and solib-search-path
4454 For SunOS and SVR4 shared libraries, you may now set the prefix for
4455 loading absolute shared library symbol files, and the search path for
4456 locating non-absolute shared library symbol files.
4458 * Live range splitting
4460 GDB can now effectively debug code for which GCC has performed live
4461 range splitting as part of its optimization. See gdb/doc/LRS for
4462 more details on the expected format of the stabs information.
4466 GDB's support for the GNU Hurd, including thread debugging, has been
4467 updated to work with current versions of the Hurd.
4471 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4472 instruction set. ARM GDB automatically detects when Thumb
4473 instructions are in use, and adjusts disassembly and backtracing
4478 GDB's MIPS target configurations now handle the MIP16 16-bit
4483 GDB now includes support for overlays; if an executable has been
4484 linked such that multiple sections are based at the same address, GDB
4485 will decide which section to use for symbolic info. You can choose to
4486 control the decision manually, using overlay commands, or implement
4487 additional target-side support and use "overlay load-target" to bring
4488 in the overlay mapping. Do "help overlay" for more detail.
4492 The command "info symbol <address>" displays information about
4493 the symbol at the specified address.
4497 The standard remote protocol now includes an extension that allows
4498 asynchronous collection and display of trace data. This requires
4499 extensive support in the target-side debugging stub. Tracing mode
4500 includes a new interaction mode in GDB and new commands: see the
4501 file tracepoint.c for more details.
4505 Configurations for embedded MIPS now include a simulator contributed
4506 by Cygnus Solutions. The simulator supports the instruction sets
4507 of most MIPS variants.
4511 Sparc configurations may now include the ERC32 simulator contributed
4512 by the European Space Agency. The simulator is not built into
4513 Sparc targets by default; configure with --enable-sim to include it.
4517 For target configurations that may include multiple variants of a
4518 basic architecture (such as MIPS and SH), you may now set the
4519 architecture explicitly. "set arch" sets, "info arch" lists
4520 the possible architectures.
4522 *** Changes in GDB-4.16:
4524 * New native configurations
4526 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4527 M68K NetBSD m68k-*-netbsd*
4528 PowerPC AIX 4.x powerpc-*-aix*
4529 PowerPC MacOS powerpc-*-macos*
4530 PowerPC Windows NT powerpcle-*-cygwin32
4531 RS/6000 AIX 4.x rs6000-*-aix4*
4535 ARM with RDP protocol arm-*-*
4536 I960 with MON960 i960-*-coff
4537 MIPS VxWorks mips*-*-vxworks*
4538 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4539 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4541 Matra Sparclet sparclet-*-*
4545 The powerpc-eabi configuration now includes the PSIM simulator,
4546 contributed by Andrew Cagney, with assistance from Mike Meissner.
4547 PSIM is a very elaborate model of the PowerPC, including not only
4548 basic instruction set execution, but also details of execution unit
4549 performance and I/O hardware. See sim/ppc/README for more details.
4553 GDB now works with Solaris 2.5.
4555 * Windows 95/NT native
4557 GDB will now work as a native debugger on Windows 95 and Windows NT.
4558 To build it from source, you must use the "gnu-win32" environment,
4559 which uses a DLL to emulate enough of Unix to run the GNU tools.
4560 Further information, binaries, and sources are available at
4561 ftp.cygnus.com, under pub/gnu-win32.
4563 * dont-repeat command
4565 If a user-defined command includes the command `dont-repeat', then the
4566 command will not be repeated if the user just types return. This is
4567 useful if the command is time-consuming to run, so that accidental
4568 extra keystrokes don't run the same command many times.
4570 * Send break instead of ^C
4572 The standard remote protocol now includes an option to send a break
4573 rather than a ^C to the target in order to interrupt it. By default,
4574 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4576 * Remote protocol timeout
4578 The standard remote protocol includes a new variable `remotetimeout'
4579 that allows you to set the number of seconds before GDB gives up trying
4580 to read from the target. The default value is 2.
4582 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4584 By default GDB will automatically keep track of objects as they are
4585 loaded and unloaded by the dynamic linker. By using the command `set
4586 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4587 when shared library events occur, thus allowing you to set breakpoints
4588 in shared libraries which are explicitly loaded by the inferior.
4590 Note this feature does not work on hpux8. On hpux9 you must link
4591 /usr/lib/end.o into your program. This feature should work
4592 automatically on hpux10.
4594 * Irix 5.x hardware watchpoint support
4596 Irix 5 configurations now support the use of hardware watchpoints.
4598 * Mips protocol "SYN garbage limit"
4600 When debugging a Mips target using the `target mips' protocol, you
4601 may set the number of characters that GDB will ignore by setting
4602 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4603 every character. The default value is 1050.
4605 * Recording and replaying remote debug sessions
4607 If you set `remotelogfile' to the name of a file, gdb will write to it
4608 a recording of a remote debug session. This recording may then be
4609 replayed back to gdb using "gdbreplay". See gdbserver/README for
4610 details. This is useful when you have a problem with GDB while doing
4611 remote debugging; you can make a recording of the session and send it
4612 to someone else, who can then recreate the problem.
4614 * Speedups for remote debugging
4616 GDB includes speedups for downloading and stepping MIPS systems using
4617 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4618 and more efficient S-record downloading.
4620 * Memory use reductions and statistics collection
4622 GDB now uses less memory and reports statistics about memory usage.
4623 Try the `maint print statistics' command, for example.
4625 *** Changes in GDB-4.15:
4627 * Psymtabs for XCOFF
4629 The symbol reader for AIX GDB now uses partial symbol tables. This
4630 can greatly improve startup time, especially for large executables.
4632 * Remote targets use caching
4634 Remote targets now use a data cache to speed up communication with the
4635 remote side. The data cache could lead to incorrect results because
4636 it doesn't know about volatile variables, thus making it impossible to
4637 debug targets which use memory mapped I/O devices. `set remotecache
4638 off' turns the the data cache off.
4640 * Remote targets may have threads
4642 The standard remote protocol now includes support for multiple threads
4643 in the target system, using new protocol commands 'H' and 'T'. See
4644 gdb/remote.c for details.
4648 If GDB is configured with `--enable-netrom', then it will include
4649 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4650 acts as though it is a bank of ROM on the target board, but you can
4651 write into it over the network. GDB's support consists only of
4652 support for fast loading into the emulated ROM; to debug, you must use
4653 another protocol, such as standard remote protocol. The usual
4654 sequence is something like
4656 target nrom <netrom-hostname>
4658 target remote <netrom-hostname>:1235
4662 GDB now includes support for the Apple Macintosh, as a host only. It
4663 may be run as either an MPW tool or as a standalone application, and
4664 it can debug through the serial port. All the usual GDB commands are
4665 available, but to the target command, you must supply "serial" as the
4666 device type instead of "/dev/ttyXX". See mpw-README in the main
4667 directory for more information on how to build. The MPW configuration
4668 scripts */mpw-config.in support only a few targets, and only the
4669 mips-idt-ecoff target has been tested.
4673 GDB configuration now uses autoconf. This is not user-visible,
4674 but does simplify configuration and building.
4678 GDB now supports hpux10.
4680 *** Changes in GDB-4.14:
4682 * New native configurations
4684 x86 FreeBSD i[345]86-*-freebsd
4685 x86 NetBSD i[345]86-*-netbsd
4686 NS32k NetBSD ns32k-*-netbsd
4687 Sparc NetBSD sparc-*-netbsd
4691 A29K VxWorks a29k-*-vxworks
4692 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4693 CPU32 EST-300 emulator m68*-*-est*
4694 PowerPC ELF powerpc-*-elf
4697 * Alpha OSF/1 support for procfs
4699 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4700 possible to attach to running processes. As the mounting of the /proc
4701 filesystem is optional on the Alpha, GDB automatically determines
4702 the availability of /proc during startup. This can lead to problems
4703 if /proc is unmounted after GDB has been started.
4705 * Arguments to user-defined commands
4707 User commands may accept up to 10 arguments separated by whitespace.
4708 Arguments are accessed within the user command via $arg0..$arg9. A
4711 print $arg0 + $arg1 + $arg2
4713 To execute the command use:
4716 Defines the command "adder" which prints the sum of its three arguments.
4717 Note the arguments are text substitutions, so they may reference variables,
4718 use complex expressions, or even perform inferior function calls.
4720 * New `if' and `while' commands
4722 This makes it possible to write more sophisticated user-defined
4723 commands. Both commands take a single argument, which is the
4724 expression to evaluate, and must be followed by the commands to
4725 execute, one per line, if the expression is nonzero, the list being
4726 terminated by the word `end'. The `if' command list may include an
4727 `else' word, which causes the following commands to be executed only
4728 if the expression is zero.
4730 * Fortran source language mode
4732 GDB now includes partial support for Fortran 77. It will recognize
4733 Fortran programs and can evaluate a subset of Fortran expressions, but
4734 variables and functions may not be handled correctly. GDB will work
4735 with G77, but does not yet know much about symbols emitted by other
4738 * Better HPUX support
4740 Most debugging facilities now work on dynamic executables for HPPAs
4741 running hpux9 or later. You can attach to running dynamically linked
4742 processes, but by default the dynamic libraries will be read-only, so
4743 for instance you won't be able to put breakpoints in them. To change
4744 that behavior do the following before running the program:
4750 This will cause the libraries to be mapped private and read-write.
4751 To revert to the normal behavior, do this:
4757 You cannot set breakpoints or examine data in the library until after
4758 the library is loaded if the function/data symbols do not have
4761 GDB can now also read debug symbols produced by the HP C compiler on
4762 HPPAs (sorry, no C++, Fortran or 68k support).
4764 * Target byte order now dynamically selectable
4766 You can choose which byte order to use with a target system, via the
4767 commands "set endian big" and "set endian little", and you can see the
4768 current setting by using "show endian". You can also give the command
4769 "set endian auto", in which case GDB will use the byte order
4770 associated with the executable. Currently, only embedded MIPS
4771 configurations support dynamic selection of target byte order.
4773 * New DOS host serial code
4775 This version uses DPMI interrupts to handle buffered I/O, so you
4776 no longer need to run asynctsr when debugging boards connected to
4779 *** Changes in GDB-4.13:
4781 * New "complete" command
4783 This lists all the possible completions for the rest of the line, if it
4784 were to be given as a command itself. This is intended for use by emacs.
4786 * Trailing space optional in prompt
4788 "set prompt" no longer adds a space for you after the prompt you set. This
4789 allows you to set a prompt which ends in a space or one that does not.
4791 * Breakpoint hit counts
4793 "info break" now displays a count of the number of times the breakpoint
4794 has been hit. This is especially useful in conjunction with "ignore"; you
4795 can ignore a large number of breakpoint hits, look at the breakpoint info
4796 to see how many times the breakpoint was hit, then run again, ignoring one
4797 less than that number, and this will get you quickly to the last hit of
4800 * Ability to stop printing at NULL character
4802 "set print null-stop" will cause GDB to stop printing the characters of
4803 an array when the first NULL is encountered. This is useful when large
4804 arrays actually contain only short strings.
4806 * Shared library breakpoints
4808 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4809 breakpoints in shared libraries before the executable is run.
4811 * Hardware watchpoints
4813 There is a new hardware breakpoint for the watch command for sparclite
4814 targets. See gdb/sparclite/hw_breakpoint.note.
4816 Hardware watchpoints are also now supported under GNU/Linux.
4820 Annotations have been added. These are for use with graphical interfaces,
4821 and are still experimental. Currently only gdba.el uses these.
4823 * Improved Irix 5 support
4825 GDB now works properly with Irix 5.2.
4827 * Improved HPPA support
4829 GDB now works properly with the latest GCC and GAS.
4831 * New native configurations
4833 Sequent PTX4 i[34]86-sequent-ptx4
4834 HPPA running OSF/1 hppa*-*-osf*
4835 Atari TT running SVR4 m68*-*-sysv4*
4836 RS/6000 LynxOS rs6000-*-lynxos*
4840 OS/9000 i[34]86-*-os9k
4841 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4844 * Hitachi SH7000 and E7000-PC ICE support
4846 There is now support for communicating with the Hitachi E7000-PC ICE.
4847 This is available automatically when GDB is configured for the SH.
4851 As usual, a variety of small fixes and improvements, both generic
4852 and configuration-specific. See the ChangeLog for more detail.
4854 *** Changes in GDB-4.12:
4856 * Irix 5 is now supported
4860 GDB-4.12 on the HPPA has a number of changes which make it unable
4861 to debug the output from the currently released versions of GCC and
4862 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4863 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4864 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4867 *** Changes in GDB-4.11:
4869 * User visible changes:
4873 The "set remotedebug" option is now consistent between the mips remote
4874 target, remote targets using the gdb-specific protocol, UDI (AMD's
4875 debug protocol for the 29k) and the 88k bug monitor. It is now an
4876 integer specifying a debug level (normally 0 or 1, but 2 means more
4877 debugging info for the mips target).
4879 * DEC Alpha native support
4881 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4882 debug info, but GDB works fairly well with the DEC compiler and should
4883 work with a future GCC release. See the README file for a few
4884 Alpha-specific notes.
4886 * Preliminary thread implementation
4888 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4890 * LynxOS native and target support for 386
4892 This release has been hosted on LynxOS 2.2, and also can be configured
4893 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4896 * Improvements in C++ mangling/demangling.
4898 This release has much better g++ debugging, specifically in name
4899 mangling/demangling, virtual function calls, print virtual table,
4900 call methods, ...etc.
4902 *** Changes in GDB-4.10:
4904 * User visible changes:
4906 Remote debugging using the GDB-specific (`target remote') protocol now
4907 supports the `load' command. This is only useful if you have some
4908 other way of getting the stub to the target system, and you can put it
4909 somewhere in memory where it won't get clobbered by the download.
4911 Filename completion now works.
4913 When run under emacs mode, the "info line" command now causes the
4914 arrow to point to the line specified. Also, "info line" prints
4915 addresses in symbolic form (as well as hex).
4917 All vxworks based targets now support a user settable option, called
4918 vxworks-timeout. This option represents the number of seconds gdb
4919 should wait for responses to rpc's. You might want to use this if
4920 your vxworks target is, perhaps, a slow software simulator or happens
4921 to be on the far side of a thin network line.
4925 This release contains support for using a DEC alpha as a GDB host for
4926 cross debugging. Native alpha debugging is not supported yet.
4929 *** Changes in GDB-4.9:
4933 This is the first GDB release which is accompanied by a matching testsuite.
4934 The testsuite requires installation of dejagnu, which should be available
4935 via ftp from most sites that carry GNU software.
4939 'Cfront' style demangling has had its name changed to 'ARM' style, to
4940 emphasize that it was written from the specifications in the C++ Annotated
4941 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4942 disclaimers, it still generated too much confusion with users attempting to
4943 use gdb with AT&T cfront.
4947 GDB now uses a standard remote interface to a simulator library.
4948 So far, the library contains simulators for the Zilog Z8001/2, the
4949 Hitachi H8/300, H8/500 and Super-H.
4951 * New targets supported
4953 H8/300 simulator h8300-hitachi-hms or h8300hms
4954 H8/500 simulator h8500-hitachi-hms or h8500hms
4955 SH simulator sh-hitachi-hms or sh
4956 Z8000 simulator z8k-zilog-none or z8ksim
4957 IDT MIPS board over serial line mips-idt-ecoff
4959 Cross-debugging to GO32 targets is supported. It requires a custom
4960 version of the i386-stub.c module which is integrated with the
4961 GO32 memory extender.
4963 * New remote protocols
4965 MIPS remote debugging protocol.
4967 * New source languages supported
4969 This version includes preliminary support for Chill, a Pascal like language
4970 used by telecommunications companies. Chill support is also being integrated
4971 into the GNU compiler, but we don't know when it will be publically available.
4974 *** Changes in GDB-4.8:
4976 * HP Precision Architecture supported
4978 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4979 version of this support was available as a set of patches from the
4980 University of Utah. GDB does not support debugging of programs
4981 compiled with the HP compiler, because HP will not document their file
4982 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4983 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4985 Many problems in the preliminary version have been fixed.
4987 * Faster and better demangling
4989 We have improved template demangling and fixed numerous bugs in the GNU style
4990 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4991 character types (wchar_t) are now supported. Demangling of each symbol is now
4992 only done once, and is cached when the symbol table for a file is read in.
4993 This results in a small increase in memory usage for C programs, a moderate
4994 increase in memory usage for C++ programs, and a fantastic speedup in
4997 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4998 from the specifications in the Annotated Reference Manual, which AT&T's
4999 compiler does not actually implement.
5001 * G++ multiple inheritance compiler problem
5003 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5004 inheritance lattices was reworked to properly discover ambiguities. We
5005 recently found an example which causes this new algorithm to fail in a
5006 very subtle way, producing bad debug information for those classes.
5007 The file 'gcc.patch' (in this directory) can be applied to gcc to
5008 circumvent the problem. A future GCC release will contain a complete
5011 The previous G++ debug info problem (mentioned below for the gdb-4.7
5012 release) is fixed in gcc version 2.3.2.
5014 * Improved configure script
5016 The `configure' script will now attempt to guess your system type if
5017 you don't supply a host system type. The old scheme of supplying a
5018 host system triplet is preferable over using this. All the magic is
5019 done in the new `config.guess' script. Examine it for details.
5021 We have also brought our configure script much more in line with the FSF's
5022 version. It now supports the --with-xxx options. In particular,
5023 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5024 The resulting GDB will not be able to read arbitrary object file formats --
5025 only the format ``expected'' to be used on the configured target system.
5026 We hope to make this the default in a future release.
5028 * Documentation improvements
5030 There's new internal documentation on how to modify GDB, and how to
5031 produce clean changes to the code. We implore people to read it
5032 before submitting changes.
5034 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5035 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5036 `info' files are also provided. To build `info' files from scratch,
5037 you will need the latest `makeinfo' release, which will be available in
5038 a future texinfo-X.Y release.
5040 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5041 We're not sure exactly which versions have this problem, but it has
5042 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5043 or better. If that isn't possible, there is a patch in
5044 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5045 around this problem.
5049 GDB now supports array constants that can be used in expressions typed in by
5050 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5051 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5054 The new directory `gdb/sparclite' contains a program that demonstrates
5055 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5057 * New native hosts supported
5059 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5060 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5062 * New targets supported
5064 AMD 29k family via UDI a29k-amd-udi or udi29k
5066 * New file formats supported
5068 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5069 HPUX core files, and SCO 3.2v2 core files.
5073 Attaching to processes now works again; thanks for the many bug reports.
5075 We have also stomped on a bunch of core dumps caused by
5076 printf_filtered("%s") problems.
5078 We eliminated a copyright problem on the rpc and ptrace header files
5079 for VxWorks, which was discovered at the last minute during the 4.7
5080 release. You should now be able to build a VxWorks GDB.
5082 You can now interrupt gdb while an attached process is running. This
5083 will cause the attached process to stop, and give control back to GDB.
5085 We fixed problems caused by using too many file descriptors
5086 for reading symbols from object files and libraries. This was
5087 especially a problem for programs that used many (~100) shared
5090 The `step' command now only enters a subroutine if there is line number
5091 information for the subroutine. Otherwise it acts like the `next'
5092 command. Previously, `step' would enter subroutines if there was
5093 any debugging information about the routine. This avoids problems
5094 when using `cc -g1' on MIPS machines.
5096 * Internal improvements
5098 GDB's internal interfaces have been improved to make it easier to support
5099 debugging of multiple languages in the future.
5101 GDB now uses a common structure for symbol information internally.
5102 Minimal symbols (derived from linkage symbols in object files), partial
5103 symbols (from a quick scan of debug information), and full symbols
5104 contain a common subset of information, making it easier to write
5105 shared code that handles any of them.
5107 * New command line options
5109 We now accept --silent as an alias for --quiet.
5113 The memory-mapped-malloc library is now licensed under the GNU Library
5114 General Public License.
5116 *** Changes in GDB-4.7:
5118 * Host/native/target split
5120 GDB has had some major internal surgery to untangle the support for
5121 hosts and remote targets. Now, when you configure GDB for a remote
5122 target, it will no longer load in all of the support for debugging
5123 local programs on the host. When fully completed and tested, this will
5124 ensure that arbitrary host/target combinations are possible.
5126 The primary conceptual shift is to separate the non-portable code in
5127 GDB into three categories. Host specific code is required any time GDB
5128 is compiled on that host, regardless of the target. Target specific
5129 code relates to the peculiarities of the target, but can be compiled on
5130 any host. Native specific code is everything else: it can only be
5131 built when the host and target are the same system. Child process
5132 handling and core file support are two common `native' examples.
5134 GDB's use of /proc for controlling Unix child processes is now cleaner.
5135 It has been split out into a single module under the `target_ops' vector,
5136 plus two native-dependent functions for each system that uses /proc.
5138 * New hosts supported
5140 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5141 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5142 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5144 * New targets supported
5146 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5147 68030 and CPU32 m68030-*-*, m68332-*-*
5149 * New native hosts supported
5151 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5152 (386bsd is not well tested yet)
5153 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5155 * New file formats supported
5157 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5158 supports reading of `a.out.adobe' object files, which are an a.out
5159 format extended with minimal information about multiple sections.
5163 `show copying' is the same as the old `info copying'.
5164 `show warranty' is the same as `info warrantee'.
5165 These were renamed for consistency. The old commands continue to work.
5167 `info handle' is a new alias for `info signals'.
5169 You can now define pre-command hooks, which attach arbitrary command
5170 scripts to any command. The commands in the hook will be executed
5171 prior to the user's command. You can also create a hook which will be
5172 executed whenever the program stops. See gdb.texinfo.
5176 We now deal with Cfront style name mangling, and can even extract type
5177 info from mangled symbols. GDB can automatically figure out which
5178 symbol mangling style your C++ compiler uses.
5180 Calling of methods and virtual functions has been improved as well.
5184 The crash that occured when debugging Sun Ansi-C compiled binaries is
5185 fixed. This was due to mishandling of the extra N_SO stabs output
5188 We also finally got Ultrix 4.2 running in house, and fixed core file
5189 support, with help from a dozen people on the net.
5191 John M. Farrell discovered that the reason that single-stepping was so
5192 slow on all of the Mips based platforms (primarily SGI and DEC) was
5193 that we were trying to demangle and lookup a symbol used for internal
5194 purposes on every instruction that was being stepped through. Changing
5195 the name of that symbol so that it couldn't be mistaken for a C++
5196 mangled symbol sped things up a great deal.
5198 Rich Pixley sped up symbol lookups in general by getting much smarter
5199 about when C++ symbol mangling is necessary. This should make symbol
5200 completion (TAB on the command line) much faster. It's not as fast as
5201 we'd like, but it's significantly faster than gdb-4.6.
5205 A new user controllable variable 'call_scratch_address' can
5206 specify the location of a scratch area to be used when GDB
5207 calls a function in the target. This is necessary because the
5208 usual method of putting the scratch area on the stack does not work
5209 in systems that have separate instruction and data spaces.
5211 We integrated changes to support the 29k UDI (Universal Debugger
5212 Interface), but discovered at the last minute that we didn't have all
5213 of the appropriate copyright paperwork. We are working with AMD to
5214 resolve this, and hope to have it available soon.
5218 We have sped up the remote serial line protocol, especially for targets
5219 with lots of registers. It now supports a new `expedited status' ('T')
5220 message which can be used in place of the existing 'S' status message.
5221 This allows the remote stub to send only the registers that GDB
5222 needs to make a quick decision about single-stepping or conditional
5223 breakpoints, eliminating the need to fetch the entire register set for
5224 each instruction being stepped through.
5226 The GDB remote serial protocol now implements a write-through cache for
5227 registers, only re-reading the registers if the target has run.
5229 There is also a new remote serial stub for SPARC processors. You can
5230 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5231 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5232 processor with a serial port.
5236 Configure.in files have become much easier to read and modify. A new
5237 `table driven' format makes it more obvious what configurations are
5238 supported, and what files each one uses.
5242 There is a new opcodes library which will eventually contain all of the
5243 disassembly routines and opcode tables. At present, it only contains
5244 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5245 disassembler (binutils/objdump) to share these routines.
5247 The libiberty library is now copylefted under the GNU Library General
5248 Public License. This allows more liberal use, and was done so libg++
5249 can use it. This makes no difference to GDB, since the Library License
5250 grants all the rights from the General Public License.
5254 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5255 reference to the stabs symbol info used by the debugger. It is (as far
5256 as we know) the only published document on this fascinating topic. We
5257 encourage you to read it, compare it to the stabs information on your
5258 system, and send improvements on the document in general (to
5259 bug-gdb@prep.ai.mit.edu).
5261 And, of course, many bugs have been fixed.
5264 *** Changes in GDB-4.6:
5266 * Better support for C++ function names
5268 GDB now accepts as input the "demangled form" of C++ overloaded function
5269 names and member function names, and can do command completion on such names
5270 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5271 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5272 Make use of command completion, it is your friend.
5274 GDB also now accepts a variety of C++ mangled symbol formats. They are
5275 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5276 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5277 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5278 for the list of formats.
5280 * G++ symbol mangling problem
5282 Recent versions of gcc have a bug in how they emit debugging information for
5283 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5284 directory) can be applied to gcc to fix the problem. Alternatively, if you
5285 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5286 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5287 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5290 * New 'maintenance' command
5292 All of the commands related to hacking GDB internals have been moved out of
5293 the main command set, and now live behind the 'maintenance' command. This
5294 can also be abbreviated as 'mt'. The following changes were made:
5296 dump-me -> maintenance dump-me
5297 info all-breakpoints -> maintenance info breakpoints
5298 printmsyms -> maintenance print msyms
5299 printobjfiles -> maintenance print objfiles
5300 printpsyms -> maintenance print psymbols
5301 printsyms -> maintenance print symbols
5303 The following commands are new:
5305 maintenance demangle Call internal GDB demangler routine to
5306 demangle a C++ link name and prints the result.
5307 maintenance print type Print a type chain for a given symbol
5309 * Change to .gdbinit file processing
5311 We now read the $HOME/.gdbinit file before processing the argv arguments
5312 (e.g. reading symbol files or core files). This allows global parameters to
5313 be set, which will apply during the symbol reading. The ./.gdbinit is still
5314 read after argv processing.
5316 * New hosts supported
5318 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5320 GNU/Linux support i386-unknown-linux or linux
5322 We are also including code to support the HP/PA running BSD and HPUX. This
5323 is almost guaranteed not to work, as we didn't have time to test or build it
5324 for this release. We are including it so that the more adventurous (or
5325 masochistic) of you can play with it. We also had major problems with the
5326 fact that the compiler that we got from HP doesn't support the -g option.
5329 * New targets supported
5331 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5333 * More smarts about finding #include files
5335 GDB now remembers the compilation directory for all include files, and for
5336 all files from which C is generated (like yacc and lex sources). This
5337 greatly improves GDB's ability to find yacc/lex sources, and include files,
5338 especially if you are debugging your program from a directory different from
5339 the one that contains your sources.
5341 We also fixed a bug which caused difficulty with listing and setting
5342 breakpoints in include files which contain C code. (In the past, you had to
5343 try twice in order to list an include file that you hadn't looked at before.)
5345 * Interesting infernals change
5347 GDB now deals with arbitrary numbers of sections, where the symbols for each
5348 section must be relocated relative to that section's landing place in the
5349 target's address space. This work was needed to support ELF with embedded
5350 stabs used by Solaris-2.0.
5352 * Bug fixes (of course!)
5354 There have been loads of fixes for the following things:
5355 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5356 i960, stabs, DOS(GO32), procfs, etc...
5358 See the ChangeLog for details.
5360 *** Changes in GDB-4.5:
5362 * New machines supported (host and target)
5364 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5366 SGI Irix-4.x mips-sgi-irix4 or iris4
5368 * New malloc package
5370 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5371 Mmalloc is capable of handling mutiple heaps of memory. It is also
5372 capable of saving a heap to a file, and then mapping it back in later.
5373 This can be used to greatly speedup the startup of GDB by using a
5374 pre-parsed symbol table which lives in a mmalloc managed heap. For
5375 more details, please read mmalloc/mmalloc.texi.
5379 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5380 'help info proc' for details.
5382 * MIPS ecoff symbol table format
5384 The code that reads MIPS symbol table format is now supported on all hosts.
5385 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5388 * File name changes for MS-DOS
5390 Many files in the config directories have been renamed to make it easier to
5391 support GDB on MS-DOSe systems (which have very restrictive file name
5392 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5393 environment) is close to working but has some remaining problems. Note
5394 that debugging of DOS programs is not supported, due to limitations
5395 in the ``operating system'', but it can be used to host cross-debugging.
5397 * Cross byte order fixes
5399 Many fixes have been made to support cross debugging of Sparc and MIPS
5400 targets from hosts whose byte order differs.
5402 * New -mapped and -readnow options
5404 If memory-mapped files are available on your system through the 'mmap'
5405 system call, you can use the -mapped option on the `file' or
5406 `symbol-file' commands to cause GDB to write the symbols from your
5407 program into a reusable file. If the program you are debugging is
5408 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5409 Future GDB debugging sessions will notice the presence of this file,
5410 and will quickly map in symbol information from it, rather than reading
5411 the symbol table from the executable program. Using the '-mapped'
5412 option in a GDB `file' or `symbol-file' command has the same effect as
5413 starting GDB with the '-mapped' command-line option.
5415 You can cause GDB to read the entire symbol table immediately by using
5416 the '-readnow' option with any of the commands that load symbol table
5417 information (or on the GDB command line). This makes the command
5418 slower, but makes future operations faster.
5420 The -mapped and -readnow options are typically combined in order to
5421 build a `fred.syms' file that contains complete symbol information.
5422 A simple GDB invocation to do nothing but build a `.syms' file for future
5425 gdb -batch -nx -mapped -readnow programname
5427 The `.syms' file is specific to the host machine on which GDB is run.
5428 It holds an exact image of GDB's internal symbol table. It cannot be
5429 shared across multiple host platforms.
5431 * longjmp() handling
5433 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5434 siglongjmp() without losing control. This feature has not yet been ported to
5435 all systems. It currently works on many 386 platforms, all MIPS-based
5436 platforms (SGI, DECstation, etc), and Sun3/4.
5440 Preliminary work has been put in to support the new Solaris OS from Sun. At
5441 this time, it can control and debug processes, but it is not capable of
5446 As always, many many bug fixes. The major areas were with g++, and mipsread.
5447 People using the MIPS-based platforms should experience fewer mysterious
5448 crashes and trashed symbol tables.
5450 *** Changes in GDB-4.4:
5452 * New machines supported (host and target)
5454 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5456 BSD Reno on Vax vax-dec-bsd
5457 Ultrix on Vax vax-dec-ultrix
5459 * New machines supported (target)
5461 AMD 29000 embedded, using EBMON a29k-none-none
5465 GDB continues to improve its handling of C++. `References' work better.
5466 The demangler has also been improved, and now deals with symbols mangled as
5467 per the Annotated C++ Reference Guide.
5469 GDB also now handles `stabs' symbol information embedded in MIPS
5470 `ecoff' symbol tables. Since the ecoff format was not easily
5471 extensible to handle new languages such as C++, this appeared to be a
5472 good way to put C++ debugging info into MIPS binaries. This option
5473 will be supported in the GNU C compiler, version 2, when it is
5476 * New features for SVR4
5478 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5479 shared libraries. Debugging dynamically linked programs should present
5480 only minor differences from debugging statically linked programs.
5482 The `info proc' command will print out information about any process
5483 on an SVR4 system (including the one you are debugging). At the moment,
5484 it prints the address mappings of the process.
5486 If you bring up GDB on another SVR4 system, please send mail to
5487 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5489 * Better dynamic linking support in SunOS
5491 Reading symbols from shared libraries which contain debugging symbols
5492 now works properly. However, there remain issues such as automatic
5493 skipping of `transfer vector' code during function calls, which
5494 make it harder to debug code in a shared library, than to debug the
5495 same code linked statically.
5499 GDB is now using the latest `getopt' routines from the FSF. This
5500 version accepts the -- prefix for options with long names. GDB will
5501 continue to accept the old forms (-option and +option) as well.
5502 Various single letter abbreviations for options have been explicity
5503 added to the option table so that they won't get overshadowed in the
5504 future by other options that begin with the same letter.
5508 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5509 Many assorted bugs have been handled. Many more remain to be handled.
5510 See the various ChangeLog files (primarily in gdb and bfd) for details.
5513 *** Changes in GDB-4.3:
5515 * New machines supported (host and target)
5517 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5518 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5519 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5521 * Almost SCO Unix support
5523 We had hoped to support:
5524 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5525 (except for core file support), but we discovered very late in the release
5526 that it has problems with process groups that render gdb unusable. Sorry
5527 about that. I encourage people to fix it and post the fixes.
5529 * Preliminary ELF and DWARF support
5531 GDB can read ELF object files on System V Release 4, and can handle
5532 debugging records for C, in DWARF format, in ELF files. This support
5533 is preliminary. If you bring up GDB on another SVR4 system, please
5534 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5539 GDB now uses the latest `readline' library. One user-visible change
5540 is that two tabs will list possible command completions, which previously
5541 required typing M-? (meta-question mark, or ESC ?).
5545 The `stepi' bug that many of you noticed has been squashed.
5546 Many bugs in C++ have been handled. Many more remain to be handled.
5547 See the various ChangeLog files (primarily in gdb and bfd) for details.
5549 * State of the MIPS world (in case you wondered):
5551 GDB can understand the symbol tables emitted by the compilers
5552 supplied by most vendors of MIPS-based machines, including DEC. These
5553 symbol tables are in a format that essentially nobody else uses.
5555 Some versions of gcc come with an assembler post-processor called
5556 mips-tfile. This program is required if you want to do source-level
5557 debugging of gcc-compiled programs. I believe FSF does not ship
5558 mips-tfile with gcc version 1, but it will eventually come with gcc
5561 Debugging of g++ output remains a problem. g++ version 1.xx does not
5562 really support it at all. (If you're lucky, you should be able to get
5563 line numbers and stack traces to work, but no parameters or local
5564 variables.) With some work it should be possible to improve the
5567 When gcc version 2 is released, you will have somewhat better luck.
5568 However, even then you will get confusing results for inheritance and
5571 We will eventually provide full debugging of g++ output on
5572 DECstations. This will probably involve some kind of stabs-in-ecoff
5573 encapulation, but the details have not been worked out yet.
5576 *** Changes in GDB-4.2:
5578 * Improved configuration
5580 Only one copy of `configure' exists now, and it is not self-modifying.
5581 Porting BFD is simpler.
5585 The `step' and `next' commands now only stop at the first instruction
5586 of a source line. This prevents the multiple stops that used to occur
5587 in switch statements, for-loops, etc. `Step' continues to stop if a
5588 function that has debugging information is called within the line.
5592 Lots of small bugs fixed. More remain.
5594 * New host supported (not target)
5596 Intel 386 PC clone running Mach i386-none-mach
5599 *** Changes in GDB-4.1:
5601 * Multiple source language support
5603 GDB now has internal scaffolding to handle several source languages.
5604 It determines the type of each source file from its filename extension,
5605 and will switch expression parsing and number formatting to match the
5606 language of the function in the currently selected stack frame.
5607 You can also specifically set the language to be used, with
5608 `set language c' or `set language modula-2'.
5612 GDB now has preliminary support for the GNU Modula-2 compiler,
5613 currently under development at the State University of New York at
5614 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5615 continue through the fall of 1991 and into 1992.
5617 Other Modula-2 compilers are currently not supported, and attempting to
5618 debug programs compiled with them will likely result in an error as the
5619 symbol table is read. Feel free to work on it, though!
5621 There are hooks in GDB for strict type checking and range checking,
5622 in the `Modula-2 philosophy', but they do not currently work.
5626 GDB can now write to executable and core files (e.g. patch
5627 a variable's value). You must turn this switch on, specify
5628 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5629 by assigning a new value to a variable. Modifications take
5632 * Automatic SunOS shared library reading
5634 When you run your program, GDB automatically determines where its
5635 shared libraries (if any) have been loaded, and reads their symbols.
5636 The `share' command is no longer needed. This also works when
5637 examining core files.
5641 You can specify the number of lines that the `list' command shows.
5644 * New machines supported (host and target)
5646 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5647 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5648 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5650 * New hosts supported (not targets)
5652 IBM RT/PC: romp-ibm-aix or rtpc
5654 * New targets supported (not hosts)
5656 AMD 29000 embedded with COFF a29k-none-coff
5657 AMD 29000 embedded with a.out a29k-none-aout
5658 Ultracomputer remote kernel debug a29k-nyu-kern
5660 * New remote interfaces
5666 *** Changes in GDB-4.0:
5670 Wide output is wrapped at good places to make the output more readable.
5672 Gdb now supports cross-debugging from a host machine of one type to a
5673 target machine of another type. Communication with the target system
5674 is over serial lines. The ``target'' command handles connecting to the
5675 remote system; the ``load'' command will download a program into the
5676 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5677 also supports debugging of realtime processes running under VxWorks,
5678 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5679 stub on the target system.
5681 New CPUs supported include the AMD 29000 and Intel 960.
5683 GDB now reads object files and symbol tables via a ``binary file''
5684 library, which allows a single copy of GDB to debug programs of multiple
5685 object file types such as a.out and coff.
5687 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5688 refcard.dvi and refcard.ps are available to format it).
5691 * Control-Variable user interface simplified
5693 All variables that control the operation of the debugger can be set
5694 by the ``set'' command, and displayed by the ``show'' command.
5696 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5697 ``Show prompt'' produces the response:
5698 Gdb's prompt is new-gdb=>.
5700 What follows are the NEW set commands. The command ``help set'' will
5701 print a complete list of old and new set commands. ``help set FOO''
5702 will give a longer description of the variable FOO. ``show'' will show
5703 all of the variable descriptions and their current settings.
5705 confirm on/off: Enables warning questions for operations that are
5706 hard to recover from, e.g. rerunning the program while
5707 it is already running. Default is ON.
5709 editing on/off: Enables EMACS style command line editing
5710 of input. Previous lines can be recalled with
5711 control-P, the current line can be edited with control-B,
5712 you can search for commands with control-R, etc.
5715 history filename NAME: NAME is where the gdb command history
5716 will be stored. The default is .gdb_history,
5717 or the value of the environment variable
5720 history size N: The size, in commands, of the command history. The
5721 default is 256, or the value of the environment variable
5724 history save on/off: If this value is set to ON, the history file will
5725 be saved after exiting gdb. If set to OFF, the
5726 file will not be saved. The default is OFF.
5728 history expansion on/off: If this value is set to ON, then csh-like
5729 history expansion will be performed on
5730 command line input. The default is OFF.
5732 radix N: Sets the default radix for input and output. It can be set
5733 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5734 in the current radix, so "set radix 10" is always a no-op.
5736 height N: This integer value is the number of lines on a page. Default
5737 is 24, the current `stty rows'' setting, or the ``li#''
5738 setting from the termcap entry matching the environment
5741 width N: This integer value is the number of characters on a line.
5742 Default is 80, the current `stty cols'' setting, or the ``co#''
5743 setting from the termcap entry matching the environment
5746 Note: ``set screensize'' is obsolete. Use ``set height'' and
5747 ``set width'' instead.
5749 print address on/off: Print memory addresses in various command displays,
5750 such as stack traces and structure values. Gdb looks
5751 more ``symbolic'' if you turn this off; it looks more
5752 ``machine level'' with it on. Default is ON.
5754 print array on/off: Prettyprint arrays. New convenient format! Default
5757 print demangle on/off: Print C++ symbols in "source" form if on,
5760 print asm-demangle on/off: Same, for assembler level printouts
5763 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5766 * Support for Epoch Environment.
5768 The epoch environment is a version of Emacs v18 with windowing. One
5769 new command, ``inspect'', is identical to ``print'', except that if you
5770 are running in the epoch environment, the value is printed in its own
5774 * Support for Shared Libraries
5776 GDB can now debug programs and core files that use SunOS shared libraries.
5777 Symbols from a shared library cannot be referenced
5778 before the shared library has been linked with the program (this
5779 happens after you type ``run'' and before the function main() is entered).
5780 At any time after this linking (including when examining core files
5781 from dynamically linked programs), gdb reads the symbols from each
5782 shared library when you type the ``sharedlibrary'' command.
5783 It can be abbreviated ``share''.
5785 sharedlibrary REGEXP: Load shared object library symbols for files
5786 matching a unix regular expression. No argument
5787 indicates to load symbols for all shared libraries.
5789 info sharedlibrary: Status of loaded shared libraries.
5794 A watchpoint stops execution of a program whenever the value of an
5795 expression changes. Checking for this slows down execution
5796 tremendously whenever you are in the scope of the expression, but is
5797 quite useful for catching tough ``bit-spreader'' or pointer misuse
5798 problems. Some machines such as the 386 have hardware for doing this
5799 more quickly, and future versions of gdb will use this hardware.
5801 watch EXP: Set a watchpoint (breakpoint) for an expression.
5803 info watchpoints: Information about your watchpoints.
5805 delete N: Deletes watchpoint number N (same as breakpoints).
5806 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5807 enable N: Re-enables watchpoint number N (same as breakpoints).
5810 * C++ multiple inheritance
5812 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5815 * C++ exception handling
5817 Gdb now supports limited C++ exception handling. Besides the existing
5818 ability to breakpoint on an exception handler, gdb can breakpoint on
5819 the raising of an exception (before the stack is peeled back to the
5822 catch FOO: If there is a FOO exception handler in the dynamic scope,
5823 set a breakpoint to catch exceptions which may be raised there.
5824 Multiple exceptions (``catch foo bar baz'') may be caught.
5826 info catch: Lists all exceptions which may be caught in the
5827 current stack frame.
5830 * Minor command changes
5832 The command ``call func (arg, arg, ...)'' now acts like the print
5833 command, except it does not print or save a value if the function's result
5834 is void. This is similar to dbx usage.
5836 The ``up'' and ``down'' commands now always print the frame they end up
5837 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5838 frames without printing.
5840 * New directory command
5842 'dir' now adds directories to the FRONT of the source search path.
5843 The path starts off empty. Source files that contain debug information
5844 about the directory in which they were compiled can be found even
5845 with an empty path; Sun CC and GCC include this information. If GDB can't
5846 find your source file in the current directory, type "dir .".
5848 * Configuring GDB for compilation
5850 For normal use, type ``./configure host''. See README or gdb.texinfo
5853 GDB now handles cross debugging. If you are remotely debugging between
5854 two different machines, type ``./configure host -target=targ''.
5855 Host is the machine where GDB will run; targ is the machine
5856 where the program that you are debugging will run.