1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.8
6 * GDB now supports hardware watchpoints on x86 GNU Hurd.
10 ** You can now access frame registers from Python scripts.
11 ** New attribute 'producer' for gdb.Symtab objects.
12 ** gdb.Objfile objects have a new attribute "progspace",
13 which is the gdb.Progspace object of the containing program space.
14 ** gdb.Objfile objects have a new attribute "owner".
15 ** gdb.Objfile objects have a new attribute "build_id",
16 which is the build ID generated when the file was built.
17 ** gdb.Objfile objects have a new method "add_separate_debug_file".
18 ** A new event "gdb.clear_objfiles" has been added, triggered when
19 selecting a new file to debug.
20 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
21 ** New function gdb.lookup_objfile.
23 New events which are triggered when GDB modifies the state of the
26 ** gdb.events.inferior_call_pre: Function call is about to be made.
27 ** gdb.events.inferior_call_post: Function call has just been made.
28 ** gdb.events.memory_changed: A memory location has been altered.
29 ** gdb.events.register_changed: A register has been altered.
31 * New Python-based convenience functions:
33 ** $_caller_is(name [, number_of_frames])
34 ** $_caller_matches(regexp [, number_of_frames])
35 ** $_any_caller_is(name [, number_of_frames])
36 ** $_any_caller_matches(regexp [, number_of_frames])
38 * GDB now supports the compilation and injection of source code into
39 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
40 to compile the source code to object code, and if successful, inject
41 and execute that code within the current context of the inferior.
42 Currently the C language is supported. The commands used to
43 interface with this new feature are:
45 compile code [-raw|-r] [--] [source code]
46 compile file [-raw|-r] filename
50 queue-signal signal-name-or-number
51 Queue a signal to be delivered to the thread when it is resumed.
53 add-auto-load-scripts-directory directory
54 Add entries to the list of directories from which to load auto-loaded
57 maint print user-registers
58 List all currently available "user" registers.
60 compile code [-r|-raw] [--] [source code]
61 Compile, inject, and execute in the inferior the executable object
62 code produced by compiling the provided source code.
64 compile file [-r|-raw] filename
65 Compile and inject into the inferior the executable object code
66 produced by compiling the source code stored in the filename
69 * On resume, GDB now always passes the signal the program had stopped
70 for to the thread the signal was sent to, even if the user changed
71 threads before resuming. Previously GDB would often (but not
72 always) deliver the signal to the thread that happens to be current
75 * Conversely, the "signal" command now consistently delivers the
76 requested signal to the current thread. GDB now asks for
77 confirmation if the program had stopped for a signal and the user
78 switched threads meanwhile.
80 * "breakpoint always-inserted" modes "off" and "auto" merged.
82 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
83 won't remove breakpoints from the target until all threads stop,
84 even in non-stop mode. The "auto" mode has been removed, and "off"
85 is now the default mode.
89 set debug symbol-lookup
90 show debug symbol-lookup
91 Control display of debugging info regarding symbol lookup.
95 ** The -list-thread-groups command outputs an exit-code field for
96 inferiors that have exited.
100 MIPS SDE mips*-sde*-elf*
104 Support for these obsolete configurations has been removed.
106 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
107 SGI Irix-5.x mips-*-irix5*
108 SGI Irix-6.x mips-*-irix6*
109 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
110 VAX running Ultrix vax-*-ultrix*
112 *** Changes in GDB 7.8
114 * New command line options
117 This is an alias for the --data-directory option.
119 * GDB supports printing and modifying of variable length automatic arrays
120 as specified in ISO C99.
122 * The ARM simulator now supports instruction level tracing
123 with or without disassembly.
127 GDB now has support for scripting using Guile. Whether this is
128 available is determined at configure time.
129 Guile version 2.0 or greater is required.
130 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
132 * New commands (for set/show, see "New options" below)
136 Invoke CODE by passing it to the Guile interpreter.
140 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
142 info auto-load guile-scripts [regexp]
143 Print the list of automatically loaded Guile scripts.
145 * The source command is now capable of sourcing Guile scripts.
146 This feature is dependent on the debugger being built with Guile support.
150 set print symbol-loading (off|brief|full)
151 show print symbol-loading
152 Control whether to print informational messages when loading symbol
153 information for a file. The default is "full", but when debugging
154 programs with large numbers of shared libraries the amount of output
157 set guile print-stack (none|message|full)
158 show guile print-stack
159 Show a stack trace when an error is encountered in a Guile script.
161 set auto-load guile-scripts (on|off)
162 show auto-load guile-scripts
163 Control auto-loading of Guile script files.
165 maint ada set ignore-descriptive-types (on|off)
166 maint ada show ignore-descriptive-types
167 Control whether the debugger should ignore descriptive types in Ada
168 programs. The default is not to ignore the descriptive types. See
169 the user manual for more details on descriptive types and the intended
170 usage of this option.
172 set auto-connect-native-target
174 Control whether GDB is allowed to automatically connect to the
175 native target for the run, attach, etc. commands when not connected
176 to any target yet. See also "target native" below.
178 set record btrace replay-memory-access (read-only|read-write)
179 show record btrace replay-memory-access
180 Control what memory accesses are allowed during replay.
182 maint set target-async (on|off)
183 maint show target-async
184 This controls whether GDB targets operate in synchronous or
185 asynchronous mode. Normally the default is asynchronous, if it is
186 available; but this can be changed to more easily debug problems
187 occurring only in synchronous mode.
189 set mi-async (on|off)
191 Control whether MI asynchronous mode is preferred. This supersedes
192 "set target-async" of previous GDB versions.
194 * "set target-async" is deprecated as a CLI option and is now an alias
195 for "set mi-async" (only puts MI into async mode).
197 * Background execution commands (e.g., "c&", "s&", etc.) are now
198 possible ``out of the box'' if the target supports them. Previously
199 the user would need to explicitly enable the possibility with the
200 "set target-async on" command.
202 * New features in the GDB remote stub, GDBserver
204 ** New option --debug-format=option1[,option2,...] allows one to add
205 additional text to each output. At present only timestamps
206 are supported: --debug-format=timestamps.
207 Timestamps can also be turned on with the
208 "monitor set debug-format timestamps" command from GDB.
210 * The 'record instruction-history' command now starts counting instructions
211 at one. This also affects the instruction ranges reported by the
212 'record function-call-history' command when given the /i modifier.
214 * The command 'record function-call-history' supports a new modifier '/c' to
215 indent the function names based on their call stack depth.
216 The fields for the '/i' and '/l' modifier have been reordered.
217 The source line range is now prefixed with 'at'.
218 The instruction range is now prefixed with 'inst'.
219 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
220 "record instruction-history" and "list" commands.
222 * The ranges given as arguments to the 'record function-call-history' and
223 'record instruction-history' commands are now inclusive.
225 * The btrace record target now supports the 'record goto' command.
226 For locations inside the execution trace, the back trace is computed
227 based on the information stored in the execution trace.
229 * The btrace record target supports limited reverse execution and replay.
230 The target does not record data and therefore does not allow reading
233 * The "catch syscall" command now works on s390*-linux* targets.
235 * The "compare-sections" command is no longer specific to target
236 remote. It now works with all targets.
238 * All native targets are now consistently called "native".
239 Consequently, the "target child", "target GNU", "target djgpp",
240 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
241 commands have been replaced with "target native". The QNX/NTO port
242 leaves the "procfs" target in place and adds a "native" target for
243 consistency with other ports. The impact on users should be minimal
244 as these commands previously either throwed an error, or were
245 no-ops. The target's name is visible in the output of the following
246 commands: "help target", "info target", "info files", "maint print
249 * The "target native" command now connects to the native target. This
250 can be used to launch native programs even when "set
251 auto-connect-native-target" is set to off.
253 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
255 * Support for Intel(R) AVX-512 registers on GNU/Linux.
256 Support displaying and modifying Intel(R) AVX-512 registers
257 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
261 qXfer:btrace:read's annex
262 The qXfer:btrace:read packet supports a new annex 'delta' to read
263 branch trace incrementally.
267 ** Valid Python operations on gdb.Value objects representing
268 structs/classes invoke the corresponding overloaded operators if
270 ** New `Xmethods' feature in the Python API. Xmethods are
271 additional methods or replacements for existing methods of a C++
272 class. This feature is useful for those cases where a method
273 defined in C++ source code could be inlined or optimized out by
274 the compiler, making it unavailable to GDB.
277 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
279 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
280 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
281 its alias "share", instead.
283 * The commands "set remotebaud" and "show remotebaud" are no longer
284 supported. Use "set serial baud" and "show serial baud" (respectively)
289 ** A new option "-gdb-set mi-async" replaces "-gdb-set
290 target-async". The latter is left as a deprecated alias of the
291 former for backward compatibility. If the target supports it,
292 CLI background execution commands are now always possible by
293 default, independently of whether the frontend stated a
294 preference for asynchronous execution with "-gdb-set mi-async".
295 Previously "-gdb-set target-async off" affected both MI execution
296 commands and CLI execution commands.
298 *** Changes in GDB 7.7
300 * Improved support for process record-replay and reverse debugging on
301 arm*-linux* targets. Support for thumb32 and syscall instruction
302 recording has been added.
304 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
306 * GDB now supports Fission DWP file format version 2.
307 http://gcc.gnu.org/wiki/DebugFission
309 * New convenience function "$_isvoid", to check whether an expression
310 is void. A void expression is an expression where the type of the
311 result is "void". For example, some convenience variables may be
312 "void" when evaluated (e.g., "$_exitcode" before the execution of
313 the program being debugged; or an undefined convenience variable).
314 Another example, when calling a function whose return type is
317 * The "maintenance print objfiles" command now takes an optional regexp.
319 * The "catch syscall" command now works on arm*-linux* targets.
321 * GDB now consistently shows "<not saved>" when printing values of
322 registers the debug info indicates have not been saved in the frame
323 and there's nowhere to retrieve them from
324 (callee-saved/call-clobbered registers):
329 (gdb) info registers rax
332 Before, the former would print "<optimized out>", and the latter
333 "*value not available*".
335 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
340 ** Frame filters and frame decorators have been added.
341 ** Temporary breakpoints are now supported.
342 ** Line tables representation has been added.
343 ** New attribute 'parent_type' for gdb.Field objects.
344 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
345 ** New attribute 'name' for gdb.Type objects.
349 Nios II ELF nios2*-*-elf
350 Nios II GNU/Linux nios2*-*-linux
351 Texas Instruments MSP430 msp430*-*-elf
353 * Removed native configurations
355 Support for these a.out NetBSD and OpenBSD obsolete configurations has
356 been removed. ELF variants of these configurations are kept supported.
358 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
359 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
360 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
361 i[34567]86-*-openbsd3.[0-3]
362 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
363 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
364 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
368 Like "catch throw", but catches a re-thrown exception.
370 Renamed from old "maint check-symtabs".
372 Perform consistency checks on symtabs.
374 Expand symtabs matching an optional regexp.
377 Display the details of GDB configure-time options.
379 maint set|show per-command
380 maint set|show per-command space
381 maint set|show per-command time
382 maint set|show per-command symtab
383 Enable display of per-command gdb resource usage.
385 remove-symbol-file FILENAME
386 remove-symbol-file -a ADDRESS
387 Remove a symbol file added via add-symbol-file. The file to remove
388 can be identified by its filename or by an address that lies within
389 the boundaries of this symbol file in memory.
392 info exceptions REGEXP
393 Display the list of Ada exceptions defined in the program being
394 debugged. If provided, only the exceptions whose names match REGEXP
399 set debug symfile off|on
401 Control display of debugging info regarding reading symbol files and
402 symbol tables within those files
404 set print raw frame-arguments
405 show print raw frame-arguments
406 Set/show whether to print frame arguments in raw mode,
407 disregarding any defined pretty-printers.
409 set remote trace-status-packet
410 show remote trace-status-packet
411 Set/show the use of remote protocol qTStatus packet.
415 Control display of debugging messages related to Nios II targets.
419 Control whether target-assisted range stepping is enabled.
421 set startup-with-shell
422 show startup-with-shell
423 Specifies whether Unix child processes are started via a shell or
428 Use the target memory cache for accesses to the code segment. This
429 improves performance of remote debugging (particularly disassembly).
431 * You can now use a literal value 'unlimited' for options that
432 interpret 0 or -1 as meaning "unlimited". E.g., "set
433 trace-buffer-size unlimited" is now an alias for "set
434 trace-buffer-size -1" and "set height unlimited" is now an alias for
437 * The "set debug symtab-create" debugging option of GDB has been changed to
438 accept a verbosity level. 0 means "off", 1 provides basic debugging
439 output, and values of 2 or greater provides more verbose output.
441 * New command-line options
443 Display the details of GDB configure-time options.
445 * The command 'tsave' can now support new option '-ctf' to save trace
446 buffer in Common Trace Format.
448 * Newly installed $prefix/bin/gcore acts as a shell interface for the
451 * GDB now implements the the C++ 'typeid' operator.
453 * The new convenience variable $_exception holds the exception being
454 thrown or caught at an exception-related catchpoint.
456 * The exception-related catchpoints, like "catch throw", now accept a
457 regular expression which can be used to filter exceptions by type.
459 * The new convenience variable $_exitsignal is automatically set to
460 the terminating signal number when the program being debugged dies
461 due to an uncaught signal.
465 ** All MI commands now accept an optional "--language" option.
466 Support for this feature can be verified by using the "-list-features"
467 command, which should contain "language-option".
469 ** The new command -info-gdb-mi-command allows the user to determine
470 whether a GDB/MI command is supported or not.
472 ** The "^error" result record returned when trying to execute an undefined
473 GDB/MI command now provides a variable named "code" whose content is the
474 "undefined-command" error code. Support for this feature can be verified
475 by using the "-list-features" command, which should contain
476 "undefined-command-error-code".
478 ** The -trace-save MI command can optionally save trace buffer in Common
481 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
483 ** The command -data-list-register-values now accepts an optional
484 "--skip-unavailable" option. When used, only the available registers
487 ** The new command -trace-frame-collected dumps collected variables,
488 computed expressions, tvars, memory and registers in a traceframe.
490 ** The commands -stack-list-locals, -stack-list-arguments and
491 -stack-list-variables now accept an option "--skip-unavailable".
492 When used, only the available locals or arguments are displayed.
494 ** The -exec-run command now accepts an optional "--start" option.
495 When used, the command follows the same semantics as the "start"
496 command, stopping the program's execution at the start of its
497 main subprogram. Support for this feature can be verified using
498 the "-list-features" command, which should contain
499 "exec-run-start-option".
501 ** The new commands -catch-assert and -catch-exceptions insert
502 catchpoints stopping the program when Ada exceptions are raised.
504 ** The new command -info-ada-exceptions provides the equivalent of
505 the new "info exceptions" command.
507 * New system-wide configuration scripts
508 A GDB installation now provides scripts suitable for use as system-wide
509 configuration scripts for the following systems:
513 * GDB now supports target-assigned range stepping with remote targets.
514 This improves the performance of stepping source lines by reducing
515 the number of control packets from/to GDB. See "New remote packets"
518 * GDB now understands the element 'tvar' in the XML traceframe info.
519 It has the id of the collected trace state variables.
521 * On S/390 targets that provide the transactional-execution feature,
522 the program interruption transaction diagnostic block (TDB) is now
523 represented as a number of additional "registers" in GDB.
529 The vCont packet supports a new 'r' action, that tells the remote
530 stub to step through an address range itself, without GDB
531 involvemement at each single-step.
533 qXfer:libraries-svr4:read's annex
534 The previously unused annex of the qXfer:libraries-svr4:read packet
535 is now used to support passing an argument list. The remote stub
536 reports support for this argument list to GDB's qSupported query.
537 The defined arguments are "start" and "prev", used to reduce work
538 necessary for library list updating, resulting in significant
541 * New features in the GDB remote stub, GDBserver
543 ** GDBserver now supports target-assisted range stepping. Currently
544 enabled on x86/x86_64 GNU/Linux targets.
546 ** GDBserver now adds element 'tvar' in the XML in the reply to
547 'qXfer:traceframe-info:read'. It has the id of the collected
548 trace state variables.
550 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
553 * New 'z' formatter for printing and examining memory, this displays the
554 value as hexadecimal zero padded on the left to the size of the type.
556 * GDB can now use Windows x64 unwinding data.
558 * The "set remotebaud" command has been replaced by "set serial baud".
559 Similarly, "show remotebaud" has been replaced by "show serial baud".
560 The "set remotebaud" and "show remotebaud" commands are still available
561 to provide backward compatibility with older versions of GDB.
563 *** Changes in GDB 7.6
565 * Target record has been renamed to record-full.
566 Record/replay is now enabled with the "record full" command.
567 This also affects settings that are associated with full record/replay
568 that have been moved from "set/show record" to "set/show record full":
570 set|show record full insn-number-max
571 set|show record full stop-at-limit
572 set|show record full memory-query
574 * A new record target "record-btrace" has been added. The new target
575 uses hardware support to record the control-flow of a process. It
576 does not support replaying the execution, but it implements the
577 below new commands for investigating the recorded execution log.
578 This new recording method can be enabled using:
582 The "record-btrace" target is only available on Intel Atom processors
583 and requires a Linux kernel 2.6.32 or later.
585 * Two new commands have been added for record/replay to give information
586 about the recorded execution without having to replay the execution.
587 The commands are only supported by "record btrace".
589 record instruction-history prints the execution history at
590 instruction granularity
592 record function-call-history prints the execution history at
595 * New native configurations
597 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
598 FreeBSD/powerpc powerpc*-*-freebsd
599 x86_64/Cygwin x86_64-*-cygwin*
600 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
604 ARM AArch64 aarch64*-*-elf
605 ARM AArch64 GNU/Linux aarch64*-*-linux
606 Lynx 178 PowerPC powerpc-*-lynx*178
607 x86_64/Cygwin x86_64-*-cygwin*
608 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
610 * If the configured location of system.gdbinit file (as given by the
611 --with-system-gdbinit option at configure time) is in the
612 data-directory (as specified by --with-gdb-datadir at configure
613 time) or in one of its subdirectories, then GDB will look for the
614 system-wide init file in the directory specified by the
615 --data-directory command-line option.
617 * New command line options:
619 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
620 other initialization files, unlike -nx which disables all of them.
622 * Removed command line options
624 -epoch This was used by the gdb mode in Epoch, an ancient fork of
627 * The 'ptype' and 'whatis' commands now accept an argument to control
630 * 'info proc' now works on some core files.
634 ** Vectors can be created with gdb.Type.vector.
636 ** Python's atexit.register now works in GDB.
638 ** Types can be pretty-printed via a Python API.
640 ** Python 3 is now supported (in addition to Python 2.4 or later)
642 ** New class gdb.Architecture exposes GDB's internal representation
643 of architecture in the Python API.
645 ** New method Frame.architecture returns the gdb.Architecture object
646 corresponding to the frame's architecture.
648 * New Python-based convenience functions:
650 ** $_memeq(buf1, buf2, length)
651 ** $_streq(str1, str2)
653 ** $_regex(str, regex)
655 * The 'cd' command now defaults to using '~' (the home directory) if not
658 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
659 default for GCC since November 2000.
661 * The command 'forward-search' can now be abbreviated as 'fo'.
663 * The command 'info tracepoints' can now display 'installed on target'
664 or 'not installed on target' for each non-pending location of tracepoint.
666 * New configure options
668 --enable-libmcheck/--disable-libmcheck
669 By default, development versions are built with -lmcheck on hosts
670 that support it, in order to help track memory corruption issues.
671 Release versions, on the other hand, are built without -lmcheck
672 by default. The --enable-libmcheck/--disable-libmcheck configure
673 options allow the user to override that default.
674 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
675 This configure option allows the user to build GDB with
676 libbabeltrace using which GDB can read Common Trace Format data.
678 * New commands (for set/show, see "New options" below)
681 Catch signals. This is similar to "handle", but allows commands and
682 conditions to be attached.
685 List the BFDs known to GDB.
687 python-interactive [command]
689 Start a Python interactive prompt, or evaluate the optional command
690 and print the result of expressions.
693 "py" is a new alias for "python".
695 enable type-printer [name]...
696 disable type-printer [name]...
697 Enable or disable type printers.
701 ** For the Renesas Super-H architecture, the "regs" command has been removed
702 (has been deprecated in GDB 7.5), and "info all-registers" should be used
707 set print type methods (on|off)
708 show print type methods
709 Control whether method declarations are displayed by "ptype".
710 The default is to show them.
712 set print type typedefs (on|off)
713 show print type typedefs
714 Control whether typedef definitions are displayed by "ptype".
715 The default is to show them.
717 set filename-display basename|relative|absolute
718 show filename-display
719 Control the way in which filenames is displayed.
720 The default is "relative", which preserves previous behavior.
722 set trace-buffer-size
723 show trace-buffer-size
724 Request target to change the size of trace buffer.
726 set remote trace-buffer-size-packet auto|on|off
727 show remote trace-buffer-size-packet
728 Control the use of the remote protocol `QTBuffer:size' packet.
732 Control display of debugging messages related to ARM AArch64.
735 set debug coff-pe-read
736 show debug coff-pe-read
737 Control display of debugging messages related to reading of COFF/PE
742 Control display of debugging messages related to Mach-O symbols
745 set debug notification
746 show debug notification
747 Control display of debugging info for async remote notification.
751 ** Command parameter changes are now notified using new async record
752 "=cmd-param-changed".
753 ** Trace frame changes caused by command "tfind" are now notified using
754 new async record "=traceframe-changed".
755 ** The creation, deletion and modification of trace state variables
756 are now notified using new async records "=tsv-created",
757 "=tsv-deleted" and "=tsv-modified".
758 ** The start and stop of process record are now notified using new
759 async record "=record-started" and "=record-stopped".
760 ** Memory changes are now notified using new async record
762 ** The data-disassemble command response will include a "fullname" field
763 containing the absolute file name when source has been requested.
764 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
765 command, to allow pattern filling of memory areas.
766 ** New commands "-catch-load"/"-catch-unload" added for intercepting
767 library load/unload events.
768 ** The response to breakpoint commands and breakpoint async records
769 includes an "installed" field containing a boolean state about each
770 non-pending tracepoint location is whether installed on target or not.
771 ** Output of the "-trace-status" command includes a "trace-file" field
772 containing the name of the trace file being examined. This field is
773 optional, and only present when examining a trace file.
774 ** The "fullname" field is now always present along with the "file" field,
775 even if the file cannot be found by GDB.
777 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
778 You must have the LZMA library available when configuring GDB for this
779 feature to be enabled. For more information, see:
780 http://fedoraproject.org/wiki/Features/MiniDebugInfo
785 Set the size of trace buffer. The remote stub reports support for this
786 packet to gdb's qSupported query.
789 Enable Branch Trace Store (BTS)-based branch tracing for the current
790 thread. The remote stub reports support for this packet to gdb's
794 Disable branch tracing for the current thread. The remote stub reports
795 support for this packet to gdb's qSupported query.
798 Read the traced branches for the current thread. The remote stub
799 reports support for this packet to gdb's qSupported query.
801 *** Changes in GDB 7.5
803 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
804 for more x32 ABI info.
806 * GDB now supports access to MIPS DSP registers on Linux targets.
808 * GDB now supports debugging microMIPS binaries.
810 * The "info os" command on GNU/Linux can now display information on
811 several new classes of objects managed by the operating system:
812 "info os procgroups" lists process groups
813 "info os files" lists file descriptors
814 "info os sockets" lists internet-domain sockets
815 "info os shm" lists shared-memory regions
816 "info os semaphores" lists semaphores
817 "info os msg" lists message queues
818 "info os modules" lists loaded kernel modules
820 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
821 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
822 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
823 options and inspect the probe arguments using the new $_probe_arg family
824 of convenience variables. You can obtain more information about SystemTap
825 in <http://sourceware.org/systemtap/>.
827 * GDB now supports reversible debugging on ARM, it allows you to
828 debug basic ARM and THUMB instructions, and provides
829 record/replay support.
831 * The option "symbol-reloading" has been deleted as it is no longer used.
835 ** GDB commands implemented in Python can now be put in command class
838 ** The "maint set python print-stack on|off" is now deleted.
840 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
841 apply "flag enum"-style pretty-printing to any enum.
843 ** gdb.lookup_symbol can now work when there is no current frame.
845 ** gdb.Symbol now has a 'line' attribute, holding the line number in
846 the source at which the symbol was defined.
848 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
849 method 'value'. The former indicates whether the symbol needs a
850 frame in order to compute its value, and the latter computes the
853 ** A new method 'referenced_value' on gdb.Value objects which can
854 dereference pointer as well as C++ reference values.
856 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
857 which return the global and static blocks (as gdb.Block objects),
858 of the underlying symbol table, respectively.
860 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
861 object associated with a PC value.
863 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
864 of the address range occupied by code for the current source line.
866 * Go language support.
867 GDB now supports debugging programs written in the Go programming
870 * GDBserver now supports stdio connections.
871 E.g. (gdb) target remote | ssh myhost gdbserver - hello
873 * The binary "gdbtui" can no longer be built or installed.
874 Use "gdb -tui" instead.
876 * GDB will now print "flag" enums specially. A flag enum is one where
877 all the enumerator values have no bits in common when pairwise
878 "and"ed. When printing a value whose type is a flag enum, GDB will
879 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
880 (gdb) print (enum E) 3
883 * The filename part of a linespec will now match trailing components
884 of a source file name. For example, "break gcc/expr.c:1000" will
885 now set a breakpoint in build/gcc/expr.c, but not
888 * The "info proc" and "generate-core-file" commands will now also
889 work on remote targets connected to GDBserver on Linux.
891 * The command "info catch" has been removed. It has been disabled
894 * The "catch exception" and "catch assert" commands now accept
895 a condition at the end of the command, much like the "break"
896 command does. For instance:
898 (gdb) catch exception Constraint_Error if Barrier = True
900 Previously, it was possible to add a condition to such catchpoints,
901 but it had to be done as a second step, after the catchpoint had been
902 created, using the "condition" command.
904 * The "info static-tracepoint-marker" command will now also work on
905 native Linux targets with in-process agent.
907 * GDB can now set breakpoints on inlined functions.
909 * The .gdb_index section has been updated to include symbols for
910 inlined functions. GDB will ignore older .gdb_index sections by
911 default, which could cause symbol files to be loaded more slowly
912 until their .gdb_index sections can be recreated. The new command
913 "set use-deprecated-index-sections on" will cause GDB to use any older
914 .gdb_index sections it finds. This will restore performance, but the
915 ability to set breakpoints on inlined functions will be lost in symbol
916 files with older .gdb_index sections.
918 The .gdb_index section has also been updated to record more information
919 about each symbol. This speeds up the "info variables", "info functions"
920 and "info types" commands when used with programs having the .gdb_index
921 section, as well as speeding up debugging with shared libraries using
922 the .gdb_index section.
924 * Ada support for GDB/MI Variable Objects has been added.
926 * GDB can now support 'breakpoint always-inserted mode' in 'record'
931 ** New command -info-os is the MI equivalent of "info os".
933 ** Output logs ("set logging" and related) now include MI output.
937 ** "set use-deprecated-index-sections on|off"
938 "show use-deprecated-index-sections on|off"
939 Controls the use of deprecated .gdb_index sections.
941 ** "catch load" and "catch unload" can be used to stop when a shared
942 library is loaded or unloaded, respectively.
944 ** "enable count" can be used to auto-disable a breakpoint after
947 ** "info vtbl" can be used to show the virtual method tables for
948 C++ and Java objects.
950 ** "explore" and its sub commands "explore value" and "explore type"
951 can be used to recursively explore values and types of
952 expressions. These commands are available only if GDB is
953 configured with '--with-python'.
955 ** "info auto-load" shows status of all kinds of auto-loaded files,
956 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
957 sequences of commands files, "info auto-load python-scripts"
958 shows status of auto-loading Python script files,
959 "info auto-load local-gdbinit" shows status of loading init file
960 (.gdbinit) from current directory and "info auto-load libthread-db" shows
961 status of inferior specific thread debugging shared library loading.
963 ** "info auto-load-scripts", "set auto-load-scripts on|off"
964 and "show auto-load-scripts" commands have been deprecated, use their
965 "info auto-load python-scripts", "set auto-load python-scripts on|off"
966 and "show auto-load python-scripts" counterparts instead.
968 ** "dprintf location,format,args..." creates a dynamic printf, which
969 is basically a breakpoint that does a printf and immediately
970 resumes your program's execution, so it is like a printf that you
971 can insert dynamically at runtime instead of at compiletime.
973 ** "set print symbol"
975 Controls whether GDB attempts to display the symbol, if any,
976 corresponding to addresses it prints. This defaults to "on", but
977 you can set it to "off" to restore GDB's previous behavior.
979 * Deprecated commands
981 ** For the Renesas Super-H architecture, the "regs" command has been
982 deprecated, and "info all-registers" should be used instead.
986 Renesas RL78 rl78-*-elf
987 HP OpenVMS ia64 ia64-hp-openvms*
989 * GDBserver supports evaluation of breakpoint conditions. When
990 support is advertised by GDBserver, GDB may be told to send the
991 breakpoint conditions in bytecode form to GDBserver. GDBserver
992 will only report the breakpoint trigger to GDB when its condition
998 show mips compression
999 Select the compressed ISA encoding used in functions that have no symbol
1000 information available. The encoding can be set to either of:
1003 and is updated automatically from ELF file flags if available.
1005 set breakpoint condition-evaluation
1006 show breakpoint condition-evaluation
1007 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1008 GDBserver ("target"). Default option "auto" chooses the most efficient
1010 This option can improve debugger efficiency depending on the speed of the
1014 Disable auto-loading globally.
1017 Show auto-loading setting of all kinds of auto-loaded files.
1019 set auto-load gdb-scripts on|off
1020 show auto-load gdb-scripts
1021 Control auto-loading of GDB canned sequences of commands files.
1023 set auto-load python-scripts on|off
1024 show auto-load python-scripts
1025 Control auto-loading of Python script files.
1027 set auto-load local-gdbinit on|off
1028 show auto-load local-gdbinit
1029 Control loading of init file (.gdbinit) from current directory.
1031 set auto-load libthread-db on|off
1032 show auto-load libthread-db
1033 Control auto-loading of inferior specific thread debugging shared library.
1035 set auto-load scripts-directory <dir1>[:<dir2>...]
1036 show auto-load scripts-directory
1037 Set a list of directories from which to load auto-loaded scripts.
1038 Automatically loaded Python scripts and GDB scripts are located in one
1039 of the directories listed by this option.
1040 The delimiter (':' above) may differ according to the host platform.
1042 set auto-load safe-path <dir1>[:<dir2>...]
1043 show auto-load safe-path
1044 Set a list of directories from which it is safe to auto-load files.
1045 The delimiter (':' above) may differ according to the host platform.
1047 set debug auto-load on|off
1048 show debug auto-load
1049 Control display of debugging info for auto-loading the files above.
1051 set dprintf-style gdb|call|agent
1053 Control the way in which a dynamic printf is performed; "gdb"
1054 requests a GDB printf command, while "call" causes dprintf to call a
1055 function in the inferior. "agent" requests that the target agent
1056 (such as GDBserver) do the printing.
1058 set dprintf-function <expr>
1059 show dprintf-function
1060 set dprintf-channel <expr>
1061 show dprintf-channel
1062 Set the function and optional first argument to the call when using
1063 the "call" style of dynamic printf.
1065 set disconnected-dprintf on|off
1066 show disconnected-dprintf
1067 Control whether agent-style dynamic printfs continue to be in effect
1068 after GDB disconnects.
1070 * New configure options
1072 --with-auto-load-dir
1073 Configure default value for the 'set auto-load scripts-directory'
1074 setting above. It defaults to '$debugdir:$datadir/auto-load',
1075 $debugdir representing global debugging info directories (available
1076 via 'show debug-file-directory') and $datadir representing GDB's data
1077 directory (available via 'show data-directory').
1079 --with-auto-load-safe-path
1080 Configure default value for the 'set auto-load safe-path' setting
1081 above. It defaults to the --with-auto-load-dir setting.
1083 --without-auto-load-safe-path
1084 Set 'set auto-load safe-path' to '/', effectively disabling this
1087 * New remote packets
1089 z0/z1 conditional breakpoints extension
1091 The z0/z1 breakpoint insertion packets have been extended to carry
1092 a list of conditional expressions over to the remote stub depending on the
1093 condition evaluation mode. The use of this extension can be controlled
1094 via the "set remote conditional-breakpoints-packet" command.
1098 Specify the signals which the remote stub may pass to the debugged
1099 program without GDB involvement.
1101 * New command line options
1103 --init-command=FILE, -ix Like --command, -x but execute it
1104 before loading inferior.
1105 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1106 execute it before loading inferior.
1108 *** Changes in GDB 7.4
1110 * GDB now handles ambiguous linespecs more consistently; the existing
1111 FILE:LINE support has been expanded to other types of linespecs. A
1112 breakpoint will now be set on all matching locations in all
1113 inferiors, and locations will be added or removed according to
1116 * GDB now allows you to skip uninteresting functions and files when
1117 stepping with the "skip function" and "skip file" commands.
1119 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1120 and "show remote hardware-watchpoint-length-limit". These allows to
1121 set or show the maximum length limit (in bytes) of a remote
1122 target hardware watchpoint.
1124 This allows e.g. to use "unlimited" hardware watchpoints with the
1125 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1126 watchpoints are slower than real hardware watchpoints but are
1127 significantly faster than gdb software watchpoints.
1131 ** The register_pretty_printer function in module gdb.printing now takes
1132 an optional `replace' argument. If True, the new printer replaces any
1135 ** The "maint set python print-stack on|off" command has been
1136 deprecated and will be deleted in GDB 7.5.
1137 A new command: "set python print-stack none|full|message" has
1138 replaced it. Additionally, the default for "print-stack" is
1139 now "message", which just prints the error message without
1142 ** A prompt substitution hook (prompt_hook) is now available to the
1145 ** A new Python module, gdb.prompt has been added to the GDB Python
1146 modules library. This module provides functionality for
1147 escape sequences in prompts (used by set/show
1148 extended-prompt). These escape sequences are replaced by their
1149 corresponding value.
1151 ** Python commands and convenience-functions located in
1152 'data-directory'/python/gdb/command and
1153 'data-directory'/python/gdb/function are now automatically loaded
1156 ** Blocks now provide four new attributes. global_block and
1157 static_block will return the global and static blocks
1158 respectively. is_static and is_global are boolean attributes
1159 that indicate if the block is one of those two types.
1161 ** Symbols now provide the "type" attribute, the type of the symbol.
1163 ** The "gdb.breakpoint" function has been deprecated in favor of
1166 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1167 of a function. This class is based on the "finish" command
1168 available in the CLI.
1170 ** Type objects for struct and union types now allow access to
1171 the fields using standard Python dictionary (mapping) methods.
1172 For example, "some_type['myfield']" now works, as does
1173 "some_type.items()".
1175 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1178 ** A new function, "deep_items" has been added to the gdb.types
1179 module in the GDB Python modules library. This function returns
1180 an iterator over the fields of a struct or union type. Unlike
1181 the standard Python "iteritems" method, it will recursively traverse
1182 any anonymous fields.
1186 ** "*stopped" events can report several new "reason"s, such as
1189 ** Breakpoint changes are now notified using new async records, like
1190 "=breakpoint-modified".
1192 ** New command -ada-task-info.
1194 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1195 $sdir specifies the default system locations of shared libraries.
1196 $pdir specifies the directory where the libpthread used by the application
1199 GDB no longer looks in $sdir and $pdir after it has searched the directories
1200 mentioned in libthread-db-search-path. If you want to search those
1201 directories, they must be specified in libthread-db-search-path.
1202 The default value of libthread-db-search-path on GNU/Linux and Solaris
1203 systems is now "$sdir:$pdir".
1205 $pdir is not supported by gdbserver, it is currently ignored.
1206 $sdir is supported by gdbserver.
1208 * New configure option --with-iconv-bin.
1209 When using the internationalization support like the one in the GNU C
1210 library, GDB will invoke the "iconv" program to get a list of supported
1211 character sets. If this program lives in a non-standard location, one can
1212 use this option to specify where to find it.
1214 * When natively debugging programs on PowerPC BookE processors running
1215 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1216 watchpoints, which specify a mask in addition to an address to watch.
1217 The mask specifies that some bits of an address (the bits which are
1218 reset in the mask) should be ignored when matching the address accessed
1219 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1220 section in the user manual for more details.
1222 * The new option --once causes GDBserver to stop listening for connections once
1223 the first connection is made. The listening port used by GDBserver will
1224 become available after that.
1226 * New commands "info macros" and "alias" have been added.
1228 * New function parameters suffix @entry specifies value of function parameter
1229 at the time the function got called. Entry values are available only since
1235 "!" is now an alias of the "shell" command.
1236 Note that no space is needed between "!" and SHELL COMMAND.
1240 watch EXPRESSION mask MASK_VALUE
1241 The watch command now supports the mask argument which allows creation
1242 of masked watchpoints, if the current architecture supports this feature.
1244 info auto-load-scripts [REGEXP]
1245 This command was formerly named "maintenance print section-scripts".
1246 It is now generally useful and is no longer a maintenance-only command.
1248 info macro [-all] [--] MACRO
1249 The info macro command has new options `-all' and `--'. The first for
1250 printing all definitions of a macro. The second for explicitly specifying
1251 the end of arguments and the beginning of the macro name in case the macro
1252 name starts with a hyphen.
1254 collect[/s] EXPRESSIONS
1255 The tracepoint collect command now takes an optional modifier "/s"
1256 that directs it to dereference pointer-to-character types and
1257 collect the bytes of memory up to a zero byte. The behavior is
1258 similar to what you see when you use the regular print command on a
1259 string. An optional integer following the "/s" sets a bound on the
1260 number of bytes that will be collected.
1263 The trace start command now interprets any supplied arguments as a
1264 note to be recorded with the trace run, with an effect similar to
1265 setting the variable trace-notes.
1268 The trace stop command now interprets any arguments as a note to be
1269 mentioned along with the tstatus report that the trace was stopped
1270 with a command. The effect is similar to setting the variable
1273 * Tracepoints can now be enabled and disabled at any time after a trace
1274 experiment has been started using the standard "enable" and "disable"
1275 commands. It is now possible to start a trace experiment with no enabled
1276 tracepoints; GDB will display a warning, but will allow the experiment to
1277 begin, assuming that tracepoints will be enabled as needed while the trace
1280 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1281 locations with 4-byte instructions, when they were previously
1282 limited to locations with instructions of 5 bytes or longer.
1286 set debug dwarf2-read
1287 show debug dwarf2-read
1288 Turns on or off display of debugging messages related to reading
1289 DWARF debug info. The default is off.
1291 set debug symtab-create
1292 show debug symtab-create
1293 Turns on or off display of debugging messages related to symbol table
1294 creation. The default is off.
1297 show extended-prompt
1298 Set the GDB prompt, and allow escape sequences to be inserted to
1299 display miscellaneous information (see 'help set extended-prompt'
1300 for the list of sequences). This prompt (and any information
1301 accessed through the escape sequences) is updated every time the
1302 prompt is displayed.
1304 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1305 show print entry-values
1306 Set printing of frame argument values at function entry. In some cases
1307 GDB can determine the value of function argument which was passed by the
1308 function caller, even if the value was modified inside the called function.
1310 set debug entry-values
1311 show debug entry-values
1312 Control display of debugging info for determining frame argument values at
1313 function entry and virtual tail call frames.
1315 set basenames-may-differ
1316 show basenames-may-differ
1317 Set whether a source file may have multiple base names.
1318 (A "base name" is the name of a file with the directory part removed.
1319 Example: The base name of "/home/user/hello.c" is "hello.c".)
1320 If set, GDB will canonicalize file names (e.g., expand symlinks)
1321 before comparing them. Canonicalization is an expensive operation,
1322 but it allows the same file be known by more than one base name.
1323 If not set (the default), all source files are assumed to have just
1324 one base name, and gdb will do file name comparisons more efficiently.
1330 Set a user name and notes for the current and any future trace runs.
1331 This is useful for long-running and/or disconnected traces, to
1332 inform others (or yourself) as to who is running the trace, supply
1333 contact information, or otherwise explain what is going on.
1335 set trace-stop-notes
1336 show trace-stop-notes
1337 Set a note attached to the trace run, that is displayed when the
1338 trace has been stopped by a tstop command. This is useful for
1339 instance as an explanation, if you are stopping a trace run that was
1340 started by someone else.
1342 * New remote packets
1346 Dynamically enable a tracepoint in a started trace experiment.
1350 Dynamically disable a tracepoint in a started trace experiment.
1354 Set the user and notes of the trace run.
1358 Query the current status of a tracepoint.
1362 Query the minimum length of instruction at which a fast tracepoint may
1365 * Dcache size (number of lines) and line-size are now runtime-configurable
1366 via "set dcache line" and "set dcache line-size" commands.
1370 Texas Instruments TMS320C6x tic6x-*-*
1374 Renesas RL78 rl78-*-elf
1376 *** Changes in GDB 7.3.1
1378 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1380 *** Changes in GDB 7.3
1382 * GDB has a new command: "thread find [REGEXP]".
1383 It finds the thread id whose name, target id, or thread extra info
1384 matches the given regular expression.
1386 * The "catch syscall" command now works on mips*-linux* targets.
1388 * The -data-disassemble MI command now supports modes 2 and 3 for
1389 dumping the instruction opcodes.
1391 * New command line options
1393 -data-directory DIR Specify DIR as the "data-directory".
1394 This is mostly for testing purposes.
1396 * The "maint set python auto-load on|off" command has been renamed to
1397 "set auto-load-scripts on|off".
1399 * GDB has a new command: "set directories".
1400 It is like the "dir" command except that it replaces the
1401 source path list instead of augmenting it.
1403 * GDB now understands thread names.
1405 On GNU/Linux, "info threads" will display the thread name as set by
1406 prctl or pthread_setname_np.
1408 There is also a new command, "thread name", which can be used to
1409 assign a name internally for GDB to display.
1412 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1413 has been integrated into GDB.
1417 ** The function gdb.Write now accepts an optional keyword 'stream'.
1418 This keyword, when provided, will direct the output to either
1419 stdout, stderr, or GDB's logging output.
1421 ** Parameters can now be be sub-classed in Python, and in particular
1422 you may implement the get_set_doc and get_show_doc functions.
1423 This improves how Parameter set/show documentation is processed
1424 and allows for more dynamic content.
1426 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1427 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1428 have an is_valid method.
1430 ** Breakpoints can now be sub-classed in Python, and in particular
1431 you may implement a 'stop' function that is executed each time
1432 the inferior reaches that breakpoint.
1434 ** New function gdb.lookup_global_symbol looks up a global symbol.
1436 ** GDB values in Python are now callable if the value represents a
1437 function. For example, if 'some_value' represents a function that
1438 takes two integer parameters and returns a value, you can call
1439 that function like so:
1441 result = some_value (10,20)
1443 ** Module gdb.types has been added.
1444 It contains a collection of utilities for working with gdb.Types objects:
1445 get_basic_type, has_field, make_enum_dict.
1447 ** Module gdb.printing has been added.
1448 It contains utilities for writing and registering pretty-printers.
1449 New classes: PrettyPrinter, SubPrettyPrinter,
1450 RegexpCollectionPrettyPrinter.
1451 New function: register_pretty_printer.
1453 ** New commands "info pretty-printers", "enable pretty-printer" and
1454 "disable pretty-printer" have been added.
1456 ** gdb.parameter("directories") is now available.
1458 ** New function gdb.newest_frame returns the newest frame in the
1461 ** The gdb.InferiorThread class has a new "name" attribute. This
1462 holds the thread's name.
1464 ** Python Support for Inferior events.
1465 Python scripts can add observers to be notified of events
1466 occurring in the process being debugged.
1467 The following events are currently supported:
1468 - gdb.events.cont Continue event.
1469 - gdb.events.exited Inferior exited event.
1470 - gdb.events.stop Signal received, and Breakpoint hit events.
1474 ** GDB now puts template parameters in scope when debugging in an
1475 instantiation. For example, if you have:
1477 template<int X> int func (void) { return X; }
1479 then if you step into func<5>, "print X" will show "5". This
1480 feature requires proper debuginfo support from the compiler; it
1481 was added to GCC 4.5.
1483 ** The motion commands "next", "finish", "until", and "advance" now
1484 work better when exceptions are thrown. In particular, GDB will
1485 no longer lose control of the inferior; instead, the GDB will
1486 stop the inferior at the point at which the exception is caught.
1487 This functionality requires a change in the exception handling
1488 code that was introduced in GCC 4.5.
1490 * GDB now follows GCC's rules on accessing volatile objects when
1491 reading or writing target state during expression evaluation.
1492 One notable difference to prior behavior is that "print x = 0"
1493 no longer generates a read of x; the value of the assignment is
1494 now always taken directly from the value being assigned.
1496 * GDB now has some support for using labels in the program's source in
1497 linespecs. For instance, you can use "advance label" to continue
1498 execution to a label.
1500 * GDB now has support for reading and writing a new .gdb_index
1501 section. This section holds a fast index of DWARF debugging
1502 information and can be used to greatly speed up GDB startup and
1503 operation. See the documentation for `save gdb-index' for details.
1505 * The "watch" command now accepts an optional "-location" argument.
1506 When used, this causes GDB to watch the memory referred to by the
1507 expression. Such a watchpoint is never deleted due to it going out
1510 * GDB now supports thread debugging of core dumps on GNU/Linux.
1512 GDB now activates thread debugging using the libthread_db library
1513 when debugging GNU/Linux core dumps, similarly to when debugging
1514 live processes. As a result, when debugging a core dump file, GDB
1515 is now able to display pthread_t ids of threads. For example, "info
1516 threads" shows the same output as when debugging the process when it
1517 was live. In earlier releases, you'd see something like this:
1520 * 1 LWP 6780 main () at main.c:10
1522 While now you see this:
1525 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1527 It is also now possible to inspect TLS variables when debugging core
1530 When debugging a core dump generated on a machine other than the one
1531 used to run GDB, you may need to point GDB at the correct
1532 libthread_db library with the "set libthread-db-search-path"
1533 command. See the user manual for more details on this command.
1535 * When natively debugging programs on PowerPC BookE processors running
1536 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1537 which stop execution of the inferior whenever it executes an instruction
1538 at any address within the specified range. See the "PowerPC Embedded"
1539 section in the user manual for more details.
1541 * New features in the GDB remote stub, GDBserver
1543 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1544 and i686 LynxOS (version 5.x).
1546 ** GDBserver is now supported on Blackfin Linux.
1548 * New native configurations
1550 ia64 HP-UX ia64-*-hpux*
1554 Analog Devices, Inc. Blackfin Processor bfin-*
1556 * Ada task switching is now supported on sparc-elf targets when
1557 debugging a program using the Ravenscar Profile. For more information,
1558 see the "Tasking Support when using the Ravenscar Profile" section
1559 in the GDB user manual.
1561 * Guile support was removed.
1563 * New features in the GNU simulator
1565 ** The --map-info flag lists all known core mappings.
1567 ** CFI flashes may be simulated via the "cfi" device.
1569 *** Changes in GDB 7.2
1571 * Shared library support for remote targets by default
1573 When GDB is configured for a generic, non-OS specific target, like
1574 for example, --target=arm-eabi or one of the many *-*-elf targets,
1575 GDB now queries remote stubs for loaded shared libraries using the
1576 `qXfer:libraries:read' packet. Previously, shared library support
1577 was always disabled for such configurations.
1581 ** Argument Dependent Lookup (ADL)
1583 In C++ ADL lookup directs function search to the namespaces of its
1584 arguments even if the namespace has not been imported.
1594 Here the compiler will search for `foo' in the namespace of 'b'
1595 and find A::foo. GDB now supports this. This construct is commonly
1596 used in the Standard Template Library for operators.
1598 ** Improved User Defined Operator Support
1600 In addition to member operators, GDB now supports lookup of operators
1601 defined in a namespace and imported with a `using' directive, operators
1602 defined in the global scope, operators imported implicitly from an
1603 anonymous namespace, and the ADL operators mentioned in the previous
1605 GDB now also supports proper overload resolution for all the previously
1606 mentioned flavors of operators.
1608 ** static const class members
1610 Printing of static const class members that are initialized in the
1611 class definition has been fixed.
1613 * Windows Thread Information Block access.
1615 On Windows targets, GDB now supports displaying the Windows Thread
1616 Information Block (TIB) structure. This structure is visible either
1617 by using the new command `info w32 thread-information-block' or, by
1618 dereferencing the new convenience variable named `$_tlb', a
1619 thread-specific pointer to the TIB. This feature is also supported
1620 when remote debugging using GDBserver.
1622 * Static tracepoints
1624 Static tracepoints are calls in the user program into a tracing
1625 library. One such library is a port of the LTTng kernel tracer to
1626 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1627 When debugging with GDBserver, GDB now supports combining the GDB
1628 tracepoint machinery with such libraries. For example: the user can
1629 use GDB to probe a static tracepoint marker (a call from the user
1630 program into the tracing library) with the new "strace" command (see
1631 "New commands" below). This creates a "static tracepoint" in the
1632 breakpoint list, that can be manipulated with the same feature set
1633 as fast and regular tracepoints. E.g., collect registers, local and
1634 global variables, collect trace state variables, and define
1635 tracepoint conditions. In addition, the user can collect extra
1636 static tracepoint marker specific data, by collecting the new
1637 $_sdata internal variable. When analyzing the trace buffer, you can
1638 inspect $_sdata like any other variable available to GDB. For more
1639 information, see the "Tracepoints" chapter in GDB user manual. New
1640 remote packets have been defined to support static tracepoints, see
1641 the "New remote packets" section below.
1643 * Better reconstruction of tracepoints after disconnected tracing
1645 GDB will attempt to download the original source form of tracepoint
1646 definitions when starting a trace run, and then will upload these
1647 upon reconnection to the target, resulting in a more accurate
1648 reconstruction of the tracepoints that are in use on the target.
1652 You can now exercise direct control over the ways that GDB can
1653 affect your program. For instance, you can disallow the setting of
1654 breakpoints, so that the program can run continuously (assuming
1655 non-stop mode). In addition, the "observer" variable is available
1656 to switch all of the different controls; in observer mode, GDB
1657 cannot affect the target's behavior at all, which is useful for
1658 tasks like diagnosing live systems in the field.
1660 * The new convenience variable $_thread holds the number of the
1663 * New remote packets
1667 Return the address of the Windows Thread Information Block of a given thread.
1671 In response to several of the tracepoint packets, the target may now
1672 also respond with a number of intermediate `qRelocInsn' request
1673 packets before the final result packet, to have GDB handle
1674 relocating an instruction to execute at a different address. This
1675 is particularly useful for stubs that support fast tracepoints. GDB
1676 reports support for this feature in the qSupported packet.
1680 List static tracepoint markers in the target program.
1684 List static tracepoint markers at a given address in the target
1687 qXfer:statictrace:read
1689 Read the static trace data collected (by a `collect $_sdata'
1690 tracepoint action). The remote stub reports support for this packet
1691 to gdb's qSupported query.
1695 Send the current settings of GDB's permission flags.
1699 Send part of the source (textual) form of a tracepoint definition,
1700 which includes location, conditional, and action list.
1702 * The source command now accepts a -s option to force searching for the
1703 script in the source search path even if the script name specifies
1706 * New features in the GDB remote stub, GDBserver
1708 - GDBserver now support tracepoints (including fast tracepoints, and
1709 static tracepoints). The feature is currently supported by the
1710 i386-linux and amd64-linux builds. See the "Tracepoints support
1711 in gdbserver" section in the manual for more information.
1713 GDBserver JIT compiles the tracepoint's conditional agent
1714 expression bytecode into native code whenever possible for low
1715 overhead dynamic tracepoints conditionals. For such tracepoints,
1716 an expression that examines program state is evaluated when the
1717 tracepoint is reached, in order to determine whether to capture
1718 trace data. If the condition is simple and false, processing the
1719 tracepoint finishes very quickly and no data is gathered.
1721 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1722 for static tracepoints support.
1724 - GDBserver now supports x86_64 Windows 64-bit debugging.
1726 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1727 it understands register description.
1729 * The --batch flag now disables pagination and queries.
1731 * X86 general purpose registers
1733 GDB now supports reading/writing byte, word and double-word x86
1734 general purpose registers directly. This means you can use, say,
1735 $ah or $ax to refer, respectively, to the byte register AH and
1736 16-bit word register AX that are actually portions of the 32-bit
1737 register EAX or 64-bit register RAX.
1739 * The `commands' command now accepts a range of breakpoints to modify.
1740 A plain `commands' following a command that creates multiple
1741 breakpoints affects all the breakpoints set by that command. This
1742 applies to breakpoints set by `rbreak', and also applies when a
1743 single `break' command creates multiple breakpoints (e.g.,
1744 breakpoints on overloaded c++ functions).
1746 * The `rbreak' command now accepts a filename specification as part of
1747 its argument, limiting the functions selected by the regex to those
1748 in the specified file.
1750 * Support for remote debugging Windows and SymbianOS shared libraries
1751 from Unix hosts has been improved. Non Windows GDB builds now can
1752 understand target reported file names that follow MS-DOS based file
1753 system semantics, such as file names that include drive letters and
1754 use the backslash character as directory separator. This makes it
1755 possible to transparently use the "set sysroot" and "set
1756 solib-search-path" on Unix hosts to point as host copies of the
1757 target's shared libraries. See the new command "set
1758 target-file-system-kind" described below, and the "Commands to
1759 specify files" section in the user manual for more information.
1763 eval template, expressions...
1764 Convert the values of one or more expressions under the control
1765 of the string template to a command line, and call it.
1767 set target-file-system-kind unix|dos-based|auto
1768 show target-file-system-kind
1769 Set or show the assumed file system kind for target reported file
1772 save breakpoints <filename>
1773 Save all current breakpoint definitions to a file suitable for use
1774 in a later debugging session. To read the saved breakpoint
1775 definitions, use the `source' command.
1777 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1780 info static-tracepoint-markers
1781 Display information about static tracepoint markers in the target.
1783 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1784 Define a static tracepoint by probing a marker at the given
1785 function, line, address, or marker ID.
1789 Enable and disable observer mode.
1791 set may-write-registers on|off
1792 set may-write-memory on|off
1793 set may-insert-breakpoints on|off
1794 set may-insert-tracepoints on|off
1795 set may-insert-fast-tracepoints on|off
1796 set may-interrupt on|off
1797 Set individual permissions for GDB effects on the target. Note that
1798 some of these settings can have undesirable or surprising
1799 consequences, particularly when changed in the middle of a session.
1800 For instance, disabling the writing of memory can prevent
1801 breakpoints from being inserted, cause single-stepping to fail, or
1802 even crash your program, if you disable after breakpoints have been
1803 inserted. However, GDB should not crash.
1805 set record memory-query on|off
1806 show record memory-query
1807 Control whether to stop the inferior if memory changes caused
1808 by an instruction cannot be recorded.
1813 The disassemble command now supports "start,+length" form of two arguments.
1817 ** GDB now provides a new directory location, called the python directory,
1818 where Python scripts written for GDB can be installed. The location
1819 of that directory is <data-directory>/python, where <data-directory>
1820 is the GDB data directory. For more details, see section `Scripting
1821 GDB using Python' in the manual.
1823 ** The GDB Python API now has access to breakpoints, symbols, symbol
1824 tables, program spaces, inferiors, threads and frame's code blocks.
1825 Additionally, GDB Parameters can now be created from the API, and
1826 manipulated via set/show in the CLI.
1828 ** New functions gdb.target_charset, gdb.target_wide_charset,
1829 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1831 ** New exception gdb.GdbError.
1833 ** Pretty-printers are now also looked up in the current program space.
1835 ** Pretty-printers can now be individually enabled and disabled.
1837 ** GDB now looks for names of Python scripts to auto-load in a
1838 special section named `.debug_gdb_scripts', in addition to looking
1839 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1841 * Tracepoint actions were unified with breakpoint commands. In particular,
1842 there are no longer differences in "info break" output for breakpoints and
1843 tracepoints and the "commands" command can be used for both tracepoints and
1844 regular breakpoints.
1848 ARM Symbian arm*-*-symbianelf*
1850 * D language support.
1851 GDB now supports debugging programs written in the D programming
1854 * GDB now supports the extended ptrace interface for PowerPC which is
1855 available since Linux kernel version 2.6.34. This automatically enables
1856 any hardware breakpoints and additional hardware watchpoints available in
1857 the processor. The old ptrace interface exposes just one hardware
1858 watchpoint and no hardware breakpoints.
1860 * GDB is now able to use the Data Value Compare (DVC) register available on
1861 embedded PowerPC processors to implement in hardware simple watchpoint
1862 conditions of the form:
1864 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1866 This works in native GDB running on Linux kernels with the extended ptrace
1867 interface mentioned above.
1869 *** Changes in GDB 7.1
1873 ** Namespace Support
1875 GDB now supports importing of namespaces in C++. This enables the
1876 user to inspect variables from imported namespaces. Support for
1877 namepace aliasing has also been added. So, if a namespace is
1878 aliased in the current scope (e.g. namepace C=A; ) the user can
1879 print variables using the alias (e.g. (gdb) print C::x).
1883 All known bugs relating to the printing of virtual base class were
1884 fixed. It is now possible to call overloaded static methods using a
1889 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1890 and reinterpret_cast<> are now handled by the C++ expression parser.
1894 Xilinx MicroBlaze microblaze-*-*
1899 Xilinx MicroBlaze microblaze
1902 * Multi-program debugging.
1904 GDB now has support for multi-program (a.k.a. multi-executable or
1905 multi-exec) debugging. This allows for debugging multiple inferiors
1906 simultaneously each running a different program under the same GDB
1907 session. See "Debugging Multiple Inferiors and Programs" in the
1908 manual for more information. This implied some user visible changes
1909 in the multi-inferior support. For example, "info inferiors" now
1910 lists inferiors that are not running yet or that have exited
1911 already. See also "New commands" and "New options" below.
1913 * New tracing features
1915 GDB's tracepoint facility now includes several new features:
1917 ** Trace state variables
1919 GDB tracepoints now include support for trace state variables, which
1920 are variables managed by the target agent during a tracing
1921 experiment. They are useful for tracepoints that trigger each
1922 other, so for instance one tracepoint can count hits in a variable,
1923 and then a second tracepoint has a condition that is true when the
1924 count reaches a particular value. Trace state variables share the
1925 $-syntax of GDB convenience variables, and can appear in both
1926 tracepoint actions and condition expressions. Use the "tvariable"
1927 command to create, and "info tvariables" to view; see "Trace State
1928 Variables" in the manual for more detail.
1932 GDB now includes an option for defining fast tracepoints, which
1933 targets may implement more efficiently, such as by installing a jump
1934 into the target agent rather than a trap instruction. The resulting
1935 speedup can be by two orders of magnitude or more, although the
1936 tradeoff is that some program locations on some target architectures
1937 might not allow fast tracepoint installation, for instance if the
1938 instruction to be replaced is shorter than the jump. To request a
1939 fast tracepoint, use the "ftrace" command, with syntax identical to
1940 the regular trace command.
1942 ** Disconnected tracing
1944 It is now possible to detach GDB from the target while it is running
1945 a trace experiment, then reconnect later to see how the experiment
1946 is going. In addition, a new variable disconnected-tracing lets you
1947 tell the target agent whether to continue running a trace if the
1948 connection is lost unexpectedly.
1952 GDB now has the ability to save the trace buffer into a file, and
1953 then use that file as a target, similarly to you can do with
1954 corefiles. You can select trace frames, print data that was
1955 collected in them, and use tstatus to display the state of the
1956 tracing run at the moment that it was saved. To create a trace
1957 file, use "tsave <filename>", and to use it, do "target tfile
1960 ** Circular trace buffer
1962 You can ask the target agent to handle the trace buffer as a
1963 circular buffer, discarding the oldest trace frames to make room for
1964 newer ones, by setting circular-trace-buffer to on. This feature may
1965 not be available for all target agents.
1970 The disassemble command, when invoked with two arguments, now requires
1971 the arguments to be comma-separated.
1974 The info variables command now displays variable definitions. Files
1975 which only declare a variable are not shown.
1978 The source command is now capable of sourcing Python scripts.
1979 This feature is dependent on the debugger being build with Python
1982 Related to this enhancement is also the introduction of a new command
1983 "set script-extension" (see below).
1985 * New commands (for set/show, see "New options" below)
1987 record save [<FILENAME>]
1988 Save a file (in core file format) containing the process record
1989 execution log for replay debugging at a later time.
1991 record restore <FILENAME>
1992 Restore the process record execution log that was saved at an
1993 earlier time, for replay debugging.
1995 add-inferior [-copies <N>] [-exec <FILENAME>]
1998 clone-inferior [-copies <N>] [ID]
1999 Make a new inferior ready to execute the same program another
2000 inferior has loaded.
2005 maint info program-spaces
2006 List the program spaces loaded into GDB.
2008 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2009 show remote interrupt-sequence
2010 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2011 as the sequence to the remote target in order to interrupt the execution.
2012 Ctrl-C is a default. Some system prefers BREAK which is high level of
2013 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2014 Magic SysRq g. It is BREAK signal and character 'g'.
2016 set remote interrupt-on-connect [on | off]
2017 show remote interrupt-on-connect
2018 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2019 remote target when gdb connects to it. This is needed when you debug
2022 set remotebreak [on | off]
2024 Deprecated. Use "set/show remote interrupt-sequence" instead.
2026 tvariable $NAME [ = EXP ]
2027 Create or modify a trace state variable.
2030 List trace state variables and their values.
2032 delete tvariable $NAME ...
2033 Delete one or more trace state variables.
2036 Evaluate the given expressions without collecting anything into the
2037 trace buffer. (Valid in tracepoint actions only.)
2039 ftrace FN / FILE:LINE / *ADDR
2040 Define a fast tracepoint at the given function, line, or address.
2042 * New expression syntax
2044 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2045 GDB now parses 0b101010 identically with 42.
2049 set follow-exec-mode new|same
2050 show follow-exec-mode
2051 Control whether GDB reuses the same inferior across an exec call or
2052 creates a new one. This is useful to be able to restart the old
2053 executable after the inferior having done an exec call.
2055 set default-collect EXPR, ...
2056 show default-collect
2057 Define a list of expressions to be collected at each tracepoint.
2058 This is a useful way to ensure essential items are not overlooked,
2059 such as registers or a critical global variable.
2061 set disconnected-tracing
2062 show disconnected-tracing
2063 If set to 1, the target is instructed to continue tracing if it
2064 loses its connection to GDB. If 0, the target is to stop tracing
2067 set circular-trace-buffer
2068 show circular-trace-buffer
2069 If set to on, the target is instructed to use a circular trace buffer
2070 and discard the oldest trace frames instead of stopping the trace due
2071 to a full trace buffer. If set to off, the trace stops when the buffer
2072 fills up. Some targets may not support this.
2074 set script-extension off|soft|strict
2075 show script-extension
2076 If set to "off", the debugger does not perform any script language
2077 recognition, and all sourced files are assumed to be GDB scripts.
2078 If set to "soft" (the default), files are sourced according to
2079 filename extension, falling back to GDB scripts if the first
2081 If set to "strict", files are sourced according to filename extension.
2083 set ada trust-PAD-over-XVS on|off
2084 show ada trust-PAD-over-XVS
2085 If off, activate a workaround against a bug in the debugging information
2086 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2087 the GCC sources for more information about the GNAT encoding and
2088 PAD types in particular). It is always safe to set this option to
2089 off, but this introduces a slight performance penalty. The default
2092 * Python API Improvements
2094 ** GDB provides the new class gdb.LazyString. This is useful in
2095 some pretty-printing cases. The new method gdb.Value.lazy_string
2096 provides a simple way to create objects of this type.
2098 ** The fields returned by gdb.Type.fields now have an
2099 `is_base_class' attribute.
2101 ** The new method gdb.Type.range returns the range of an array type.
2103 ** The new method gdb.parse_and_eval can be used to parse and
2104 evaluate an expression.
2106 * New remote packets
2109 Define a trace state variable.
2112 Get the current value of a trace state variable.
2115 Set desired tracing behavior upon disconnection.
2118 Set the trace buffer to be linear or circular.
2121 Get data about the tracepoints currently in use.
2125 Process record now works correctly with hardware watchpoints.
2127 Multiple bug fixes have been made to the mips-irix port, making it
2128 much more reliable. In particular:
2129 - Debugging threaded applications is now possible again. Previously,
2130 GDB would hang while starting the program, or while waiting for
2131 the program to stop at a breakpoint.
2132 - Attaching to a running process no longer hangs.
2133 - An error occurring while loading a core file has been fixed.
2134 - Changing the value of the PC register now works again. This fixes
2135 problems observed when using the "jump" command, or when calling
2136 a function from GDB, or even when assigning a new value to $pc.
2137 - With the "finish" and "return" commands, the return value for functions
2138 returning a small array is now correctly printed.
2139 - It is now possible to break on shared library code which gets executed
2140 during a shared library init phase (code executed while executing
2141 their .init section). Previously, the breakpoint would have no effect.
2142 - GDB is now able to backtrace through the signal handler for
2143 non-threaded programs.
2145 PIE (Position Independent Executable) programs debugging is now supported.
2146 This includes debugging execution of PIC (Position Independent Code) shared
2147 libraries although for that, it should be possible to run such libraries as an
2150 *** Changes in GDB 7.0
2152 * GDB now has an interface for JIT compilation. Applications that
2153 dynamically generate code can create symbol files in memory and register
2154 them with GDB. For users, the feature should work transparently, and
2155 for JIT developers, the interface is documented in the GDB manual in the
2156 "JIT Compilation Interface" chapter.
2158 * Tracepoints may now be conditional. The syntax is as for
2159 breakpoints; either an "if" clause appended to the "trace" command,
2160 or the "condition" command is available. GDB sends the condition to
2161 the target for evaluation using the same bytecode format as is used
2162 for tracepoint actions.
2164 * The disassemble command now supports: an optional /r modifier, print the
2165 raw instructions in hex as well as in symbolic form, and an optional /m
2166 modifier to print mixed source+assembly.
2168 * Process record and replay
2170 In a architecture environment that supports ``process record and
2171 replay'', ``process record and replay'' target can record a log of
2172 the process execution, and replay it with both forward and reverse
2175 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2176 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2177 set execution-direction {forward|reverse}, for targets that support
2180 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2181 feature is available with a native GDB running on kernel version
2184 * GDB now has support for multi-byte and wide character sets on the
2185 target. Strings whose character type is wchar_t, char16_t, or
2186 char32_t are now correctly printed. GDB supports wide- and unicode-
2187 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2188 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2189 `printf'. This feature requires iconv to work properly; if your
2190 system does not have a working iconv, GDB can use GNU libiconv. See
2191 the installation instructions for more information.
2193 * GDB now supports automatic retrieval of shared library files from
2194 remote targets. To use this feature, specify a system root that begins
2195 with the `remote:' prefix, either via the `set sysroot' command or via
2196 the `--with-sysroot' configure-time option.
2198 * "info sharedlibrary" now takes an optional regex of libraries to show,
2199 and it now reports if a shared library has no debugging information.
2201 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2202 now complete on file names.
2204 * When completing in expressions, gdb will attempt to limit
2205 completions to allowable structure or union fields, where appropriate.
2206 For instance, consider:
2208 # struct example { int f1; double f2; };
2209 # struct example variable;
2212 If the user types TAB at the end of this command line, the available
2213 completions will be "f1" and "f2".
2215 * Inlined functions are now supported. They show up in backtraces, and
2216 the "step", "next", and "finish" commands handle them automatically.
2218 * GDB now supports the token-splicing (##) and stringification (#)
2219 operators when expanding macros. It also supports variable-arity
2222 * GDB now supports inspecting extra signal information, exported by
2223 the new $_siginfo convenience variable. The feature is currently
2224 implemented on linux ARM, i386 and amd64.
2226 * GDB can now display the VFP floating point registers and NEON vector
2227 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2228 can provide these registers (requires Linux 2.6.30 or later). Remote
2229 and simulator targets may also provide them.
2231 * New remote packets
2234 Search memory for a sequence of bytes.
2237 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2238 operation over reliable transport links. Use of this packet is
2239 controlled by the `set remote noack-packet' command.
2242 Kill the process with the specified process ID. Use this in preference
2243 to `k' when multiprocess protocol extensions are supported.
2246 Obtains additional operating system information
2250 Read or write additional signal information.
2252 * Removed remote protocol undocumented extension
2254 An undocumented extension to the remote protocol's `S' stop reply
2255 packet that permited the stub to pass a process id was removed.
2256 Remote servers should use the `T' stop reply packet instead.
2258 * GDB now supports multiple function calling conventions according to the
2259 DWARF-2 DW_AT_calling_convention function attribute.
2261 * The SH target utilizes the aforementioned change to distinguish between gcc
2262 and Renesas calling convention. It also adds the new CLI commands
2263 `set/show sh calling-convention'.
2265 * GDB can now read compressed debug sections, as produced by GNU gold
2266 with the --compress-debug-sections=zlib flag.
2268 * 64-bit core files are now supported on AIX.
2270 * Thread switching is now supported on Tru64.
2272 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2273 which will be allocated using malloc later in program execution.
2275 * The qXfer:libraries:read remote procotol packet now allows passing a
2276 list of section offsets.
2278 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2279 conditions handling signals delivered during attach or thread creation
2280 have also been fixed.
2282 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2283 From the user's standpoint, all unqualified instances of True and False
2284 are treated as the standard definitions, regardless of context.
2286 * GDB now parses C++ symbol and type names more flexibly. For
2289 template<typename T> class C { };
2292 GDB will now correctly handle all of:
2294 ptype C<char const *>
2295 ptype C<char const*>
2296 ptype C<const char *>
2297 ptype C<const char*>
2299 * New features in the GDB remote stub, gdbserver
2301 - The "--wrapper" command-line argument tells gdbserver to use a
2302 wrapper program to launch programs for debugging.
2304 - On PowerPC and S/390 targets, it is now possible to use a single
2305 gdbserver executable to debug both 32-bit and 64-bit programs.
2306 (This requires gdbserver itself to be built as a 64-bit executable.)
2308 - gdbserver uses the new noack protocol mode for TCP connections to
2309 reduce communications latency, if also supported and enabled in GDB.
2311 - Support for the sparc64-linux-gnu target is now included in
2314 - The amd64-linux build of gdbserver now supports debugging both
2315 32-bit and 64-bit programs.
2317 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2318 now support hardware watchpoints, and will use them automatically
2323 GDB now has support for scripting using Python. Whether this is
2324 available is determined at configure time.
2326 New GDB commands can now be written in Python.
2328 * Ada tasking support
2330 Ada tasks can now be inspected in GDB. The following commands have
2334 Print the list of Ada tasks.
2336 Print detailed information about task number N.
2338 Print the task number of the current task.
2340 Switch the context of debugging to task number N.
2342 * Support for user-defined prefixed commands. The "define" command can
2343 add new commands to existing prefixes, e.g. "target".
2345 * Multi-inferior, multi-process debugging.
2347 GDB now has generalized support for multi-inferior debugging. See
2348 "Debugging Multiple Inferiors" in the manual for more information.
2349 Although availability still depends on target support, the command
2350 set is more uniform now. The GNU/Linux specific multi-forks support
2351 has been migrated to this new framework. This implied some user
2352 visible changes; see "New commands" and also "Removed commands"
2355 * Target descriptions can now describe the target OS ABI. See the
2356 "Target Description Format" section in the user manual for more
2359 * Target descriptions can now describe "compatible" architectures
2360 to indicate that the target can execute applications for a different
2361 architecture in addition to those for the main target architecture.
2362 See the "Target Description Format" section in the user manual for
2365 * Multi-architecture debugging.
2367 GDB now includes general supports for debugging applications on
2368 hybrid systems that use more than one single processor architecture
2369 at the same time. Each such hybrid architecture still requires
2370 specific support to be added. The only hybrid architecture supported
2371 in this version of GDB is the Cell Broadband Engine.
2373 * GDB now supports integrated debugging of Cell/B.E. applications that
2374 use both the PPU and SPU architectures. To enable support for hybrid
2375 Cell/B.E. debugging, you need to configure GDB to support both the
2376 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2377 --enable-targets configure option.
2379 * Non-stop mode debugging.
2381 For some targets, GDB now supports an optional mode of operation in
2382 which you can examine stopped threads while other threads continue
2383 to execute freely. This is referred to as non-stop mode, with the
2384 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2385 section in the user manual for more information.
2387 To be able to support remote non-stop debugging, a remote stub needs
2388 to implement the non-stop mode remote protocol extensions, as
2389 described in the "Remote Non-Stop" section of the user manual. The
2390 GDB remote stub, gdbserver, has been adjusted to support these
2391 extensions on linux targets.
2393 * New commands (for set/show, see "New options" below)
2395 catch syscall [NAME(S) | NUMBER(S)]
2396 Catch system calls. Arguments, which should be names of system
2397 calls or their numbers, mean catch only those syscalls. Without
2398 arguments, every syscall will be caught. When the inferior issues
2399 any of the specified syscalls, GDB will stop and announce the system
2400 call, both when it is called and when its call returns. This
2401 feature is currently available with a native GDB running on the
2402 Linux Kernel, under the following architectures: x86, x86_64,
2403 PowerPC and PowerPC64.
2405 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2407 Search memory for a sequence of bytes.
2409 maint set python print-stack
2410 maint show python print-stack
2411 Show a stack trace when an error is encountered in a Python script.
2414 Invoke CODE by passing it to the Python interpreter.
2419 These allow macros to be defined, undefined, and listed
2423 Show operating system information about processes.
2426 List the inferiors currently under GDB's control.
2429 Switch focus to inferior number NUM.
2432 Detach from inferior number NUM.
2435 Kill inferior number NUM.
2439 set spu stop-on-load
2440 show spu stop-on-load
2441 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2443 set spu auto-flush-cache
2444 show spu auto-flush-cache
2445 Control whether to automatically flush the software-managed cache
2446 during Cell/B.E. debugging.
2448 set sh calling-convention
2449 show sh calling-convention
2450 Control the calling convention used when calling SH target functions.
2453 show debug timestamp
2454 Control display of timestamps with GDB debugging output.
2456 set disassemble-next-line
2457 show disassemble-next-line
2458 Control display of disassembled source lines or instructions when
2461 set remote noack-packet
2462 show remote noack-packet
2463 Set/show the use of remote protocol QStartNoAckMode packet. See above
2464 under "New remote packets."
2466 set remote query-attached-packet
2467 show remote query-attached-packet
2468 Control use of remote protocol `qAttached' (query-attached) packet.
2470 set remote read-siginfo-object
2471 show remote read-siginfo-object
2472 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2475 set remote write-siginfo-object
2476 show remote write-siginfo-object
2477 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2480 set remote reverse-continue
2481 show remote reverse-continue
2482 Control use of remote protocol 'bc' (reverse-continue) packet.
2484 set remote reverse-step
2485 show remote reverse-step
2486 Control use of remote protocol 'bs' (reverse-step) packet.
2488 set displaced-stepping
2489 show displaced-stepping
2490 Control displaced stepping mode. Displaced stepping is a way to
2491 single-step over breakpoints without removing them from the debuggee.
2492 Also known as "out-of-line single-stepping".
2495 show debug displaced
2496 Control display of debugging info for displaced stepping.
2498 maint set internal-error
2499 maint show internal-error
2500 Control what GDB does when an internal error is detected.
2502 maint set internal-warning
2503 maint show internal-warning
2504 Control what GDB does when an internal warning is detected.
2509 Use a wrapper program to launch programs for debugging.
2511 set multiple-symbols (all|ask|cancel)
2512 show multiple-symbols
2513 The value of this variable can be changed to adjust the debugger behavior
2514 when an expression or a breakpoint location contains an ambiguous symbol
2515 name (an overloaded function name, for instance).
2517 set breakpoint always-inserted
2518 show breakpoint always-inserted
2519 Keep breakpoints always inserted in the target, as opposed to inserting
2520 them when resuming the target, and removing them when the target stops.
2521 This option can improve debugger performance on slow remote targets.
2523 set arm fallback-mode (arm|thumb|auto)
2524 show arm fallback-mode
2525 set arm force-mode (arm|thumb|auto)
2527 These commands control how ARM GDB determines whether instructions
2528 are ARM or Thumb. The default for both settings is auto, which uses
2529 the current CPSR value for instructions without symbols; previous
2530 versions of GDB behaved as if "set arm fallback-mode arm".
2532 set disable-randomization
2533 show disable-randomization
2534 Standalone programs run with the virtual address space randomization enabled
2535 by default on some platforms. This option keeps the addresses stable across
2536 multiple debugging sessions.
2540 Control whether other threads are stopped or not when some thread hits
2545 Requests that asynchronous execution is enabled in the target, if available.
2546 In this case, it's possible to resume target in the background, and interact
2547 with GDB while the target is running. "show target-async" displays the
2548 current state of asynchronous execution of the target.
2550 set target-wide-charset
2551 show target-wide-charset
2552 The target-wide-charset is the name of the character set that GDB
2553 uses when printing characters whose type is wchar_t.
2555 set tcp auto-retry (on|off)
2557 set tcp connect-timeout
2558 show tcp connect-timeout
2559 These commands allow GDB to retry failed TCP connections to a remote stub
2560 with a specified timeout period; this is useful if the stub is launched
2561 in parallel with GDB but may not be ready to accept connections immediately.
2563 set libthread-db-search-path
2564 show libthread-db-search-path
2565 Control list of directories which GDB will search for appropriate
2568 set schedule-multiple (on|off)
2569 show schedule-multiple
2570 Allow GDB to resume all threads of all processes or only threads of
2571 the current process.
2575 Use more aggressive caching for accesses to the stack. This improves
2576 performance of remote debugging (particularly backtraces) without
2577 affecting correctness.
2579 set interactive-mode (on|off|auto)
2580 show interactive-mode
2581 Control whether GDB runs in interactive mode (on) or not (off).
2582 When in interactive mode, GDB waits for the user to answer all
2583 queries. Otherwise, GDB does not wait and assumes the default
2584 answer. When set to auto (the default), GDB determines which
2585 mode to use based on the stdin settings.
2590 For program forks, this is replaced by the new more generic `info
2591 inferiors' command. To list checkpoints, you can still use the
2592 `info checkpoints' command, which was an alias for the `info forks'
2596 Replaced by the new `inferior' command. To switch between
2597 checkpoints, you can still use the `restart' command, which was an
2598 alias for the `fork' command.
2601 This is removed, since some targets don't have a notion of
2602 processes. To switch between processes, you can still use the
2603 `inferior' command using GDB's own inferior number.
2606 For program forks, this is replaced by the new more generic `kill
2607 inferior' command. To delete a checkpoint, you can still use the
2608 `delete checkpoint' command, which was an alias for the `delete
2612 For program forks, this is replaced by the new more generic `detach
2613 inferior' command. To detach a checkpoint, you can still use the
2614 `detach checkpoint' command, which was an alias for the `detach
2617 * New native configurations
2619 x86/x86_64 Darwin i[34567]86-*-darwin*
2621 x86_64 MinGW x86_64-*-mingw*
2625 Lattice Mico32 lm32-*
2626 x86 DICOS i[34567]86-*-dicos*
2627 x86_64 DICOS x86_64-*-dicos*
2630 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2631 (mingw32ce) debugging.
2637 These commands were actually not implemented on any target.
2639 *** Changes in GDB 6.8
2641 * New native configurations
2643 NetBSD/hppa hppa*-*netbsd*
2644 Xtensa GNU/Linux xtensa*-*-linux*
2648 NetBSD/hppa hppa*-*-netbsd*
2649 Xtensa GNU/Lunux xtensa*-*-linux*
2651 * Change in command line behavior -- corefiles vs. process ids.
2653 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2654 attaching to process NUMBER fails, GDB no longer attempts to open a
2655 core file named NUMBER. Attaching to a program using the -c option
2656 is no longer supported. Instead, use the '-p' or '--pid' options.
2658 * GDB can now be built as a native debugger for debugging Windows x86
2659 (mingw32) Portable Executable (PE) programs.
2661 * Pending breakpoints no longer change their number when their address
2664 * GDB now supports breakpoints with multiple locations,
2665 including breakpoints on C++ constructors, inside C++ templates,
2666 and in inlined functions.
2668 * GDB's ability to debug optimized code has been improved. GDB more
2669 accurately identifies function bodies and lexical blocks that occupy
2670 more than one contiguous range of addresses.
2672 * Target descriptions can now describe registers for PowerPC.
2674 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2675 registers on PowerPC targets.
2677 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2678 targets even when the libthread_db library is not available.
2680 * The GDB remote stub, gdbserver, now supports the new file transfer
2681 commands (remote put, remote get, and remote delete).
2683 * The GDB remote stub, gdbserver, now supports run and attach in
2684 extended-remote mode.
2686 * hppa*64*-*-hpux11* target broken
2687 The debugger is unable to start a program and fails with the following
2688 error: "Error trying to get information about dynamic linker".
2689 The gdb-6.7 release is also affected.
2691 * GDB now supports the --enable-targets= configure option to allow
2692 building a single GDB executable that supports multiple remote
2693 target architectures.
2695 * GDB now supports debugging C and C++ programs which use the
2696 Decimal Floating Point extension. In addition, the PowerPC target
2697 now has a set of pseudo-registers to inspect decimal float values
2698 stored in two consecutive float registers.
2700 * The -break-insert MI command can optionally create pending
2703 * Improved support for debugging Ada
2704 Many improvements to the Ada language support have been made. These
2706 - Better support for Ada2005 interface types
2707 - Improved handling of arrays and slices in general
2708 - Better support for Taft-amendment types
2709 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2711 - Improved command completion in Ada
2714 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2719 set print frame-arguments (all|scalars|none)
2720 show print frame-arguments
2721 The value of this variable can be changed to control which argument
2722 values should be printed by the debugger when displaying a frame.
2727 Transfer files to and from a remote target, and delete remote files.
2734 Transfer files to and from a remote target, and delete remote files.
2736 * New remote packets
2743 Open, close, read, write, and delete files on the remote system.
2746 Attach to an existing process on the remote system, in extended-remote
2750 Run a new process on the remote system, in extended-remote mode.
2752 *** Changes in GDB 6.7
2754 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2755 bfd, libiberty and opcodes, as revealed by static analysis donated by
2756 Coverity, Inc. (http://scan.coverity.com).
2758 * When looking up multiply-defined global symbols, GDB will now prefer the
2759 symbol definition in the current shared library if it was built using the
2760 -Bsymbolic linker option.
2762 * When the Text User Interface (TUI) is not configured, GDB will now
2763 recognize the -tui command-line option and print a message that the TUI
2766 * The GDB remote stub, gdbserver, now has lower overhead for high
2767 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2769 * GDB for MIPS targets now autodetects whether a remote target provides
2770 32-bit or 64-bit register values.
2772 * Support for C++ member pointers has been improved.
2774 * GDB now understands XML target descriptions, which specify the
2775 target's overall architecture. GDB can read a description from
2776 a local file or over the remote serial protocol.
2778 * Vectors of single-byte data use a new integer type which is not
2779 automatically displayed as character or string data.
2781 * The /s format now works with the print command. It displays
2782 arrays of single-byte integers and pointers to single-byte integers
2785 * Target descriptions can now describe target-specific registers,
2786 for architectures which have implemented the support (currently
2787 only ARM, M68K, and MIPS).
2789 * GDB and the GDB remote stub, gdbserver, now support the XScale
2792 * The GDB remote stub, gdbserver, has been updated to support
2793 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2794 has been rewritten to use the standard GDB remote protocol.
2796 * GDB can now step into C++ functions which are called through thunks.
2798 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2800 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2801 layout. It also supports a TextSeg= and DataSeg= response when only
2802 segment base addresses (rather than offsets) are available.
2804 * The /i format now outputs any trailing branch delay slot instructions
2805 immediately following the last instruction within the count specified.
2807 * The GDB remote protocol "T" stop reply packet now supports a
2808 "library" response. Combined with the new "qXfer:libraries:read"
2809 packet, this response allows GDB to debug shared libraries on targets
2810 where the operating system manages the list of loaded libraries (e.g.
2811 Windows and SymbianOS).
2813 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2814 (DLLs) on Windows and Windows CE targets.
2816 * GDB now supports a faster verification that a .debug file matches its binary
2817 according to its build-id signature, if the signature is present.
2823 Enable or disable hardware flow control (RTS/CTS) on the serial port
2824 when debugging using remote targets.
2826 set mem inaccessible-by-default
2827 show mem inaccessible-by-default
2828 If the target supplies a memory map, for instance via the remote
2829 protocol's "qXfer:memory-map:read" packet, setting this variable
2830 prevents GDB from accessing memory outside the memory map. This
2831 is useful for targets with memory mapped registers or which react
2832 badly to accesses of unmapped address space.
2834 set breakpoint auto-hw
2835 show breakpoint auto-hw
2836 If the target supplies a memory map, for instance via the remote
2837 protocol's "qXfer:memory-map:read" packet, setting this variable
2838 lets GDB use hardware breakpoints automatically for memory regions
2839 where it can not use software breakpoints. This covers both the
2840 "break" command and internal breakpoints used for other commands
2841 including "next" and "finish".
2844 catch exception unhandled
2845 Stop the program execution when Ada exceptions are raised.
2848 Stop the program execution when an Ada assertion failed.
2852 Set an alternate system root for target files. This is a more
2853 general version of "set solib-absolute-prefix", which is now
2854 an alias to "set sysroot".
2857 Provide extended SPU facility status information. This set of
2858 commands is available only when debugging the Cell/B.E. SPU
2861 * New native configurations
2863 OpenBSD/sh sh*-*openbsd*
2866 unset tdesc filename
2868 Use the specified local file as an XML target description, and do
2869 not query the target for its built-in description.
2873 OpenBSD/sh sh*-*-openbsd*
2874 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2875 Toshiba Media Processor mep-elf
2877 * New remote packets
2880 Ignore the specified signals; pass them directly to the debugged program
2881 without stopping other threads or reporting them to GDB.
2883 qXfer:features:read:
2884 Read an XML target description from the target, which describes its
2889 Read or write contents of an spufs file on the target system. These
2890 packets are available only on the Cell/B.E. SPU architecture.
2892 qXfer:libraries:read:
2893 Report the loaded shared libraries. Combined with new "T" packet
2894 response, this packet allows GDB to debug shared libraries on
2895 targets where the operating system manages the list of loaded
2896 libraries (e.g. Windows and SymbianOS).
2900 Support for these obsolete configurations has been removed.
2908 i[34567]86-*-lynxos*
2909 i[34567]86-*-netware*
2910 i[34567]86-*-sco3.2v5*
2911 i[34567]86-*-sco3.2v4*
2913 i[34567]86-*-sysv4.2*
2916 i[34567]86-*-unixware2*
2917 i[34567]86-*-unixware*
2926 * Other removed features
2933 Various m68k-only ROM monitors.
2940 Various Renesas ROM monitors and debugging interfaces for SH and
2945 Support for a Macraigor serial interface to on-chip debugging.
2946 GDB does not directly support the newer parallel or USB
2951 A debug information format. The predecessor to DWARF 2 and
2952 DWARF 3, which are still supported.
2954 Support for the HP aCC compiler on HP-UX/PA-RISC
2956 SOM-encapsulated symbolic debugging information, automatic
2957 invocation of pxdb, and the aCC custom C++ ABI. This does not
2958 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2959 with aCC can still be debugged on an assembly level.
2961 MIPS ".pdr" sections
2963 A MIPS-specific format used to describe stack frame layout
2964 in debugging information.
2968 GDB could work with an older version of Guile to debug
2969 the interpreter and Scheme programs running in it.
2971 set mips stack-arg-size
2972 set mips saved-gpreg-size
2974 Use "set mips abi" to control parameter passing for MIPS.
2976 *** Changes in GDB 6.6
2981 Cell Broadband Engine SPU spu-elf
2983 * GDB can now be configured as a cross-debugger targeting native Windows
2984 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2985 running on a Windows system over TCP/IP to debug Windows programs.
2987 * The GDB remote stub, gdbserver, has been updated to support Windows and
2988 Cygwin debugging. Both single-threaded and multi-threaded programs are
2991 * The "set trust-readonly-sections" command works again. This command was
2992 broken in GDB 6.3, 6.4, and 6.5.
2994 * The "load" command now supports writing to flash memory, if the remote
2995 stub provides the required support.
2997 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2998 longer requires symbolic debug information (e.g. DWARF-2).
3003 unset substitute-path
3004 show substitute-path
3005 Manage a list of substitution rules that GDB uses to rewrite the name
3006 of the directories where the sources are located. This can be useful
3007 for instance when the sources were moved to a different location
3008 between compilation and debugging.
3012 Print each CLI command as it is executed. Each command is prefixed with
3013 a number of `+' symbols representing the nesting depth.
3014 The source command now has a `-v' option to enable the same feature.
3018 The ARM Demon monitor support (RDP protocol, "target rdp").
3020 Kernel Object Display, an embedded debugging feature which only worked with
3021 an obsolete version of Cisco IOS.
3023 The 'set download-write-size' and 'show download-write-size' commands.
3025 * New remote packets
3028 Tell a stub about GDB client features, and request remote target features.
3029 The first feature implemented is PacketSize, which allows the target to
3030 specify the size of packets it can handle - to minimize the number of
3031 packets required and improve performance when connected to a remote
3035 Fetch an OS auxilliary vector from the remote stub. This packet is a
3036 more efficient replacement for qPart:auxv:read.
3038 qXfer:memory-map:read:
3039 Fetch a memory map from the remote stub, including information about
3040 RAM, ROM, and flash memory devices.
3045 Erase and program a flash memory device.
3047 * Removed remote packets
3050 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3051 used it, and only gdbserver implemented it.
3053 *** Changes in GDB 6.5
3057 Renesas M32C/M16C m32c-elf
3059 Morpho Technologies ms1 ms1-elf
3063 init-if-undefined Initialize a convenience variable, but
3064 only if it doesn't already have a value.
3066 The following commands are presently only implemented for native GNU/Linux:
3068 checkpoint Save a snapshot of the program state.
3070 restart <n> Return the program state to a
3071 previously saved state.
3073 info checkpoints List currently saved checkpoints.
3075 delete-checkpoint <n> Delete a previously saved checkpoint.
3077 set|show detach-on-fork Tell gdb whether to detach from a newly
3078 forked process, or to keep debugging it.
3080 info forks List forks of the user program that
3081 are available to be debugged.
3083 fork <n> Switch to debugging one of several
3084 forks of the user program that are
3085 available to be debugged.
3087 delete-fork <n> Delete a fork from the list of forks
3088 that are available to be debugged (and
3089 kill the forked process).
3091 detach-fork <n> Delete a fork from the list of forks
3092 that are available to be debugged (and
3093 allow the process to continue).
3097 Morpho Technologies ms2 ms1-elf
3099 * Improved Windows host support
3101 GDB now builds as a cross debugger hosted on i686-mingw32, including
3102 native console support, and remote communications using either
3103 network sockets or serial ports.
3105 * Improved Modula-2 language support
3107 GDB can now print most types in the Modula-2 syntax. This includes:
3108 basic types, set types, record types, enumerated types, range types,
3109 pointer types and ARRAY types. Procedure var parameters are correctly
3110 printed and hexadecimal addresses and character constants are also
3111 written in the Modula-2 syntax. Best results can be obtained by using
3112 GNU Modula-2 together with the -gdwarf-2 command line option.
3116 The ARM rdi-share module.
3118 The Netware NLM debug server.
3120 *** Changes in GDB 6.4
3122 * New native configurations
3124 OpenBSD/arm arm*-*-openbsd*
3125 OpenBSD/mips64 mips64-*-openbsd*
3129 Morpho Technologies ms1 ms1-elf
3131 * New command line options
3133 --batch-silent As for --batch, but totally silent.
3134 --return-child-result The debugger will exist with the same value
3135 the child (debugged) program exited with.
3136 --eval-command COMMAND, -ex COMMAND
3137 Execute a single GDB CLI command. This may be
3138 specified multiple times and in conjunction
3139 with the --command (-x) option.
3141 * Deprecated commands removed
3143 The following commands, that were deprecated in 2000, have been
3147 set|show arm disassembly-flavor set|show arm disassembler
3148 othernames set arm disassembler
3149 set|show remotedebug set|show debug remote
3150 set|show archdebug set|show debug arch
3151 set|show eventdebug set|show debug event
3154 * New BSD user-level threads support
3156 It is now possible to debug programs using the user-level threads
3157 library on OpenBSD and FreeBSD. Currently supported (target)
3160 FreeBSD/amd64 x86_64-*-freebsd*
3161 FreeBSD/i386 i386-*-freebsd*
3162 OpenBSD/i386 i386-*-openbsd*
3164 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3165 are not yet supported.
3167 * New support for Matsushita MN10300 w/sim added
3168 (Work in progress). mn10300-elf.
3170 * REMOVED configurations and files
3172 VxWorks and the XDR protocol *-*-vxworks
3173 Motorola MCORE mcore-*-*
3174 National Semiconductor NS32000 ns32k-*-*
3176 * New "set print array-indexes" command
3178 After turning this setting "on", GDB prints the index of each element
3179 when displaying arrays. The default is "off" to preserve the previous
3182 * VAX floating point support
3184 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3186 * User-defined command support
3188 In addition to using $arg0..$arg9 for argument passing, it is now possible
3189 to use $argc to determine now many arguments have been passed. See the
3190 section on user-defined commands in the user manual for more information.
3192 *** Changes in GDB 6.3:
3194 * New command line option
3196 GDB now accepts -l followed by a number to set the timeout for remote
3199 * GDB works with GCC -feliminate-dwarf2-dups
3201 GDB now supports a more compact representation of DWARF-2 debug
3202 information using DW_FORM_ref_addr references. These are produced
3203 by GCC with the option -feliminate-dwarf2-dups and also by some
3204 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3205 to use -feliminate-dwarf2-dups.
3207 * Internationalization
3209 When supported by the host system, GDB will be built with
3210 internationalization (libintl). The task of marking up the sources is
3211 continued, we're looking forward to our first translation.
3215 Initial support for debugging programs compiled with the GNAT
3216 implementation of the Ada programming language has been integrated
3217 into GDB. In this release, support is limited to expression evaluation.
3219 * New native configurations
3221 GNU/Linux/m32r m32r-*-linux-gnu
3225 GDB's remote protocol now includes support for the 'p' packet. This
3226 packet is used to fetch individual registers from a remote inferior.
3228 * END-OF-LIFE registers[] compatibility module
3230 GDB's internal register infrastructure has been completely rewritten.
3231 The new infrastructure making possible the implementation of key new
3232 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3235 GDB 6.3 will be the last release to include the the registers[]
3236 compatibility module that allowed out-of-date configurations to
3237 continue to work. This change directly impacts the following
3247 powerpc bdm protocol
3249 Unless there is activity to revive these configurations, they will be
3250 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3252 * OBSOLETE configurations and files
3254 Configurations that have been declared obsolete in this release have
3255 been commented out. Unless there is activity to revive these
3256 configurations, the next release of GDB will have their sources
3257 permanently REMOVED.
3266 *** Changes in GDB 6.2.1:
3268 * MIPS `break main; run' gave an heuristic-fence-post warning
3270 When attempting to run even a simple program, a warning about
3271 heuristic-fence-post being hit would be reported. This problem has
3274 * MIPS IRIX 'long double' crashed GDB
3276 When examining a long double variable, GDB would get a segmentation
3277 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3278 IRIX long double values).
3282 A bug in the VAX stack code was causing problems with the "next"
3283 command. This problem has been fixed.
3285 *** Changes in GDB 6.2:
3287 * Fix for ``many threads''
3289 On GNU/Linux systems that use the NPTL threads library, a program
3290 rapidly creating and deleting threads would confuse GDB leading to the
3293 ptrace: No such process.
3294 thread_db_get_info: cannot get thread info: generic error
3296 This problem has been fixed.
3298 * "-async" and "-noasync" options removed.
3300 Support for the broken "-noasync" option has been removed (it caused
3303 * New ``start'' command.
3305 This command runs the program until the begining of the main procedure.
3307 * New BSD Kernel Data Access Library (libkvm) interface
3309 Using ``target kvm'' it is now possible to debug kernel core dumps and
3310 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3311 platforms. Currently supported (native-only) configurations are:
3313 FreeBSD/amd64 x86_64-*-freebsd*
3314 FreeBSD/i386 i?86-*-freebsd*
3315 NetBSD/i386 i?86-*-netbsd*
3316 NetBSD/m68k m68*-*-netbsd*
3317 NetBSD/sparc sparc-*-netbsd*
3318 OpenBSD/amd64 x86_64-*-openbsd*
3319 OpenBSD/i386 i?86-*-openbsd*
3320 OpenBSD/m68k m68*-openbsd*
3321 OpenBSD/sparc sparc-*-openbsd*
3323 * Signal trampoline code overhauled
3325 Many generic problems with GDB's signal handling code have been fixed.
3326 These include: backtraces through non-contiguous stacks; recognition
3327 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3328 call; backtrace through a signal trampoline; step into and out of
3329 signal handlers; and single-stepping in the signal trampoline.
3331 Please note that kernel bugs are a limiting factor here. These
3332 features have been shown to work on an s390 GNU/Linux system that
3333 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3335 * Cygwin support for DWARF 2 added.
3337 * New native configurations
3339 GNU/Linux/hppa hppa*-*-linux*
3340 OpenBSD/hppa hppa*-*-openbsd*
3341 OpenBSD/m68k m68*-*-openbsd*
3342 OpenBSD/m88k m88*-*-openbsd*
3343 OpenBSD/powerpc powerpc-*-openbsd*
3344 NetBSD/vax vax-*-netbsd*
3345 OpenBSD/vax vax-*-openbsd*
3347 * END-OF-LIFE frame compatibility module
3349 GDB's internal frame infrastructure has been completely rewritten.
3350 The new infrastructure making it possible to support key new features
3351 including DWARF 2 Call Frame Information. To aid in the task of
3352 migrating old configurations to this new infrastructure, a
3353 compatibility module, that allowed old configurations to continue to
3354 work, was also included.
3356 GDB 6.2 will be the last release to include this frame compatibility
3357 module. This change directly impacts the following configurations:
3367 Unless there is activity to revive these configurations, they will be
3368 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3370 * REMOVED configurations and files
3372 Sun 3, running SunOS 3 m68*-*-sunos3*
3373 Sun 3, running SunOS 4 m68*-*-sunos4*
3374 Sun 2, running SunOS 3 m68000-*-sunos3*
3375 Sun 2, running SunOS 4 m68000-*-sunos4*
3376 Motorola 680x0 running LynxOS m68*-*-lynxos*
3377 AT&T 3b1/Unix pc m68*-att-*
3378 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3379 decstation mips-dec-* mips-little-*
3380 riscos mips-*-riscos* mips-*-sysv*
3381 sonymips mips-sony-*
3382 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3384 *** Changes in GDB 6.1.1:
3386 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3388 The TUI (Text-mode User Interface) is now built as part of a default
3389 GDB configuration. It is enabled by either selecting the TUI with the
3390 command line option "-i=tui" or by running the separate "gdbtui"
3391 program. For more information on the TUI, see the manual "Debugging
3394 * Pending breakpoint support (also included in GDB 6.1)
3396 Support has been added to allow you to specify breakpoints in shared
3397 libraries that have not yet been loaded. If a breakpoint location
3398 cannot be found, and the "breakpoint pending" option is set to auto,
3399 GDB queries you if you wish to make the breakpoint pending on a future
3400 shared-library load. If and when GDB resolves the breakpoint symbol,
3401 the pending breakpoint is removed as one or more regular breakpoints
3404 Pending breakpoints are very useful for GCJ Java debugging.
3406 * Fixed ISO-C build problems
3408 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3409 non ISO-C code that stopped them being built using a more strict ISO-C
3410 compiler (e.g., IBM's C compiler).
3412 * Fixed build problem on IRIX 5
3414 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3415 wasn't able to compile compile on an IRIX 5 system.
3417 * Added execute permission to gdb/gdbserver/configure
3419 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3420 permission. This bug would cause configure to fail on a number of
3421 systems (Solaris, IRIX). Ref: server/519.
3423 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3425 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3426 has been updated to use constant array sizes.
3428 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3430 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3431 its generated DWARF Call Frame Info. This encoding was causing GDB to
3432 panic, that panic has been fixed. Ref: gdb/1628.
3434 * Fixed a problem when examining parameters in shared library code.
3436 When examining parameters in optimized shared library code generated
3437 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3438 not available''. GDB now correctly displays the variable's value.
3440 *** Changes in GDB 6.1:
3442 * Removed --with-mmalloc
3444 Support for the mmalloc memory manager has been removed, as it
3445 conflicted with the internal gdb byte cache.
3447 * Changes in AMD64 configurations
3449 The AMD64 target now includes the %cs and %ss registers. As a result
3450 the AMD64 remote protocol has changed; this affects the floating-point
3451 and SSE registers. If you rely on those registers for your debugging,
3452 you should upgrade gdbserver on the remote side.
3454 * Revised SPARC target
3456 The SPARC target has been completely revised, incorporating the
3457 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3458 support for LynxOS and SunOS 4 has been dropped. Calling functions
3459 from within GDB on operating systems with a non-executable stack
3460 (Solaris, OpenBSD) now works.
3464 GDB has a new C++ demangler which does a better job on the mangled
3465 names generated by current versions of g++. It also runs faster, so
3466 with this and other changes gdb should now start faster on large C++
3469 * DWARF 2 Location Expressions
3471 GDB support for location expressions has been extended to support function
3472 arguments and frame bases. Older versions of GDB could crash when they
3475 * C++ nested types and namespaces
3477 GDB's support for nested types and namespaces in C++ has been
3478 improved, especially if you use the DWARF 2 debugging format. (This
3479 is the default for recent versions of GCC on most platforms.)
3480 Specifically, if you have a class "Inner" defined within a class or
3481 namespace "Outer", then GDB realizes that the class's name is
3482 "Outer::Inner", not simply "Inner". This should greatly reduce the
3483 frequency of complaints about not finding RTTI symbols. In addition,
3484 if you are stopped at inside of a function defined within a namespace,
3485 GDB modifies its name lookup accordingly.
3487 * New native configurations
3489 NetBSD/amd64 x86_64-*-netbsd*
3490 OpenBSD/amd64 x86_64-*-openbsd*
3491 OpenBSD/alpha alpha*-*-openbsd*
3492 OpenBSD/sparc sparc-*-openbsd*
3493 OpenBSD/sparc64 sparc64-*-openbsd*
3495 * New debugging protocols
3497 M32R with SDI protocol m32r-*-elf*
3499 * "set prompt-escape-char" command deleted.
3501 The command "set prompt-escape-char" has been deleted. This command,
3502 and its very obscure effet on GDB's prompt, was never documented,
3503 tested, nor mentioned in the NEWS file.
3505 * OBSOLETE configurations and files
3507 Configurations that have been declared obsolete in this release have
3508 been commented out. Unless there is activity to revive these
3509 configurations, the next release of GDB will have their sources
3510 permanently REMOVED.
3512 Sun 3, running SunOS 3 m68*-*-sunos3*
3513 Sun 3, running SunOS 4 m68*-*-sunos4*
3514 Sun 2, running SunOS 3 m68000-*-sunos3*
3515 Sun 2, running SunOS 4 m68000-*-sunos4*
3516 Motorola 680x0 running LynxOS m68*-*-lynxos*
3517 AT&T 3b1/Unix pc m68*-att-*
3518 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3519 decstation mips-dec-* mips-little-*
3520 riscos mips-*-riscos* mips-*-sysv*
3521 sonymips mips-sony-*
3522 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3524 * REMOVED configurations and files
3526 SGI Irix-4.x mips-sgi-irix4 or iris4
3527 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3528 Z8000 simulator z8k-zilog-none or z8ksim
3529 Matsushita MN10200 w/simulator mn10200-*-*
3530 H8/500 simulator h8500-hitachi-hms or h8500hms
3531 HP/PA running BSD hppa*-*-bsd*
3532 HP/PA running OSF/1 hppa*-*-osf*
3533 HP/PA Pro target hppa*-*-pro*
3534 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3535 386BSD i[3456]86-*-bsd*
3536 Sequent family i[3456]86-sequent-sysv4*
3537 i[3456]86-sequent-sysv*
3538 i[3456]86-sequent-bsd*
3539 SPARC running LynxOS sparc-*-lynxos*
3540 SPARC running SunOS 4 sparc-*-sunos4*
3541 Tsqware Sparclet sparclet-*-*
3542 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3544 *** Changes in GDB 6.0:
3548 Support for debugging the Objective-C programming language has been
3549 integrated into GDB.
3551 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3553 DWARF 2's Call Frame Information makes available compiler generated
3554 information that more exactly describes the program's run-time stack.
3555 By using this information, GDB is able to provide more robust stack
3558 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3559 have been updated to use a new backtrace mechanism which includes
3560 DWARF 2 CFI support.
3564 GDB's remote protocol has been extended to include support for hosted
3565 file I/O (where the remote target uses GDB's file system). See GDB's
3566 remote protocol documentation for details.
3568 * All targets using the new architecture framework.
3570 All of GDB's targets have been updated to use the new internal
3571 architecture framework. The way is now open for future GDB releases
3572 to include cross-architecture native debugging support (i386 on amd64,
3575 * GNU/Linux's Thread Local Storage (TLS)
3577 GDB now includes support for for the GNU/Linux implementation of
3578 per-thread variables.
3580 * GNU/Linux's Native POSIX Thread Library (NPTL)
3582 GDB's thread code has been updated to work with either the new
3583 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3585 * Separate debug info.
3587 GDB, in conjunction with BINUTILS, now supports a mechanism for
3588 automatically loading debug information from a separate file. Instead
3589 of shipping full debug and non-debug versions of system libraries,
3590 system integrators can now instead ship just the stripped libraries
3591 and optional debug files.
3593 * DWARF 2 Location Expressions
3595 DWARF 2 Location Expressions allow the compiler to more completely
3596 describe the location of variables (even in optimized code) to the
3599 GDB now includes preliminary support for location expressions (support
3600 for DW_OP_piece is still missing).
3604 A number of long standing bugs that caused GDB to die while starting a
3605 Java application have been fixed. GDB's Java support is now
3606 considered "useable".
3608 * GNU/Linux support for fork, vfork, and exec.
3610 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3611 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3614 * GDB supports logging output to a file
3616 There are two new commands, "set logging" and "show logging", which can be
3617 used to capture GDB's output to a file.
3619 * The meaning of "detach" has changed for gdbserver
3621 The "detach" command will now resume the application, as documented. To
3622 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3625 * d10v, m68hc11 `regs' command deprecated
3627 The `info registers' command has been updated so that it displays the
3628 registers using a format identical to the old `regs' command.
3632 A new command, "maint set profile on/off", has been added. This command can
3633 be used to enable or disable profiling while running GDB, to profile a
3634 session or a set of commands. In addition there is a new configure switch,
3635 "--enable-profiling", which will cause GDB to be compiled with profiling
3636 data, for more informative profiling results.
3638 * Default MI syntax changed to "mi2".
3640 The default MI (machine interface) syntax, enabled by the command line
3641 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3642 "mi1", can be enabled by specifying the option "-i=mi1".
3644 Support for the original "mi0" syntax (included in GDB 5.0) has been
3647 Fix for gdb/192: removed extraneous space when displaying frame level.
3648 Fix for gdb/672: update changelist is now output in mi list format.
3649 Fix for gdb/702: a -var-assign that updates the value now shows up
3650 in a subsequent -var-update.
3652 * New native configurations.
3654 FreeBSD/amd64 x86_64-*-freebsd*
3656 * Multi-arched targets.
3658 HP/PA HPUX11 hppa*-*-hpux*
3659 Renesas M32R/D w/simulator m32r-*-elf*
3661 * OBSOLETE configurations and files
3663 Configurations that have been declared obsolete in this release have
3664 been commented out. Unless there is activity to revive these
3665 configurations, the next release of GDB will have their sources
3666 permanently REMOVED.
3668 Z8000 simulator z8k-zilog-none or z8ksim
3669 Matsushita MN10200 w/simulator mn10200-*-*
3670 H8/500 simulator h8500-hitachi-hms or h8500hms
3671 HP/PA running BSD hppa*-*-bsd*
3672 HP/PA running OSF/1 hppa*-*-osf*
3673 HP/PA Pro target hppa*-*-pro*
3674 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3675 Sequent family i[3456]86-sequent-sysv4*
3676 i[3456]86-sequent-sysv*
3677 i[3456]86-sequent-bsd*
3678 Tsqware Sparclet sparclet-*-*
3679 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3681 * REMOVED configurations and files
3684 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3685 IBM AIX PS/2 i[3456]86-*-aix
3686 i386 running Mach 3.0 i[3456]86-*-mach3*
3687 i386 running Mach i[3456]86-*-mach*
3688 i386 running OSF/1 i[3456]86-*osf1mk*
3689 HP/Apollo 68k Family m68*-apollo*-sysv*,
3691 m68*-hp-bsd*, m68*-hp-hpux*
3692 Argonaut Risc Chip (ARC) arc-*-*
3693 Mitsubishi D30V d30v-*-*
3694 Fujitsu FR30 fr30-*-elf*
3695 OS/9000 i[34]86-*-os9k
3696 I960 with MON960 i960-*-coff
3698 * MIPS $fp behavior changed
3700 The convenience variable $fp, for the MIPS, now consistently returns
3701 the address of the current frame's base. Previously, depending on the
3702 context, $fp could refer to either $sp or the current frame's base
3703 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3704 The GNU Source-Level Debugger''.
3706 *** Changes in GDB 5.3:
3708 * GNU/Linux shared library multi-threaded performance improved.
3710 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3711 `/proc', in preference to `ptrace' for memory reads. This may result
3712 in an improvement in the start-up time of multi-threaded, shared
3713 library applications when run under GDB. One GDB user writes: ``loads
3714 shared libs like mad''.
3716 * ``gdbserver'' now supports multi-threaded applications on some targets
3718 Support for debugging multi-threaded applications which use
3719 the GNU/Linux LinuxThreads package has been added for
3720 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3721 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3723 * GDB now supports C/C++ preprocessor macros.
3725 GDB now expands preprocessor macro invocations in C/C++ expressions,
3726 and provides various commands for showing macro definitions and how
3729 The new command `macro expand EXPRESSION' expands any macro
3730 invocations in expression, and shows the result.
3732 The new command `show macro MACRO-NAME' shows the definition of the
3733 macro named MACRO-NAME, and where it was defined.
3735 Most compilers don't include information about macros in the debugging
3736 information by default. In GCC 3.1, for example, you need to compile
3737 your program with the options `-gdwarf-2 -g3'. If the macro
3738 information is present in the executable, GDB will read it.
3740 * Multi-arched targets.
3742 DEC Alpha (partial) alpha*-*-*
3743 DEC VAX (partial) vax-*-*
3745 National Semiconductor NS32000 (partial) ns32k-*-*
3746 Motorola 68000 (partial) m68k-*-*
3747 Motorola MCORE mcore-*-*
3751 Fujitsu FRV architecture added by Red Hat frv*-*-*
3754 * New native configurations
3756 Alpha NetBSD alpha*-*-netbsd*
3757 SH NetBSD sh*-*-netbsdelf*
3758 MIPS NetBSD mips*-*-netbsd*
3759 UltraSPARC NetBSD sparc64-*-netbsd*
3761 * OBSOLETE configurations and files
3763 Configurations that have been declared obsolete in this release have
3764 been commented out. Unless there is activity to revive these
3765 configurations, the next release of GDB will have their sources
3766 permanently REMOVED.
3768 Mitsubishi D30V d30v-*-*
3769 OS/9000 i[34]86-*-os9k
3770 IBM AIX PS/2 i[3456]86-*-aix
3771 Fujitsu FR30 fr30-*-elf*
3772 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3773 Argonaut Risc Chip (ARC) arc-*-*
3774 i386 running Mach 3.0 i[3456]86-*-mach3*
3775 i386 running Mach i[3456]86-*-mach*
3776 i386 running OSF/1 i[3456]86-*osf1mk*
3777 HP/Apollo 68k Family m68*-apollo*-sysv*,
3779 m68*-hp-bsd*, m68*-hp-hpux*
3780 I960 with MON960 i960-*-coff
3782 * OBSOLETE languages
3784 CHILL, a Pascal like language used by telecommunications companies.
3786 * REMOVED configurations and files
3788 AMD 29k family via UDI a29k-amd-udi, udi29k
3789 A29K VxWorks a29k-*-vxworks
3790 AMD 29000 embedded, using EBMON a29k-none-none
3791 AMD 29000 embedded with COFF a29k-none-coff
3792 AMD 29000 embedded with a.out a29k-none-aout
3794 testsuite/gdb.hp/gdb.threads-hp/ directory
3796 * New command "set max-user-call-depth <nnn>"
3798 This command allows the user to limit the call depth of user-defined
3799 commands. The default is 1024.
3801 * Changes in FreeBSD/i386 native debugging.
3803 Support for the "generate-core-file" has been added.
3805 * New commands "dump", "append", and "restore".
3807 These commands allow data to be copied from target memory
3808 to a bfd-format or binary file (dump and append), and back
3809 from a file into memory (restore).
3811 * Improved "next/step" support on multi-processor Alpha Tru64.
3813 The previous single-step mechanism could cause unpredictable problems,
3814 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3815 of a software single-step mechanism prevents this.
3817 *** Changes in GDB 5.2.1:
3825 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3826 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3827 Fix, by Joel Brobecker imported from mainline.
3829 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3830 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3831 Fix, by Fred Fish, imported from mainline.
3833 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3834 Surprisingly enough, it works now.
3835 By Michal Ludvig, imported from mainline.
3837 i386 hardware watchpoint support:
3838 avoid misses on second run for some targets.
3839 By Pierre Muller, imported from mainline.
3841 *** Changes in GDB 5.2:
3843 * New command "set trust-readonly-sections on[off]".
3845 This command is a hint that tells gdb that read-only sections
3846 really are read-only (ie. that their contents will not change).
3847 In this mode, gdb will go to the object file rather than the
3848 target to read memory from read-only sections (such as ".text").
3849 This can be a significant performance improvement on some
3850 (notably embedded) targets.
3852 * New command "generate-core-file" (or "gcore").
3854 This new gdb command allows the user to drop a core file of the child
3855 process state at any time. So far it's been implemented only for
3856 GNU/Linux and Solaris, but should be relatively easily ported to other
3857 hosts. Argument is core file name (defaults to core.<pid>).
3859 * New command line option
3861 GDB now accepts --pid or -p followed by a process id.
3863 * Change in command line behavior -- corefiles vs. process ids.
3865 There is a subtle behavior in the way in which GDB handles
3866 command line arguments. The first non-flag argument is always
3867 a program to debug, but the second non-flag argument may either
3868 be a corefile or a process id. Previously, GDB would attempt to
3869 open the second argument as a corefile, and if that failed, would
3870 issue a superfluous error message and then attempt to attach it as
3871 a process. Now, if the second argument begins with a non-digit,
3872 it will be treated as a corefile. If it begins with a digit,
3873 GDB will attempt to attach it as a process, and if no such process
3874 is found, will then attempt to open it as a corefile.
3876 * Changes in ARM configurations.
3878 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3879 configuration is fully multi-arch.
3881 * New native configurations
3883 ARM NetBSD arm*-*-netbsd*
3884 x86 OpenBSD i[3456]86-*-openbsd*
3885 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3886 Sparc64 running FreeBSD sparc64-*-freebsd*
3890 Sanyo XStormy16 xstormy16-elf
3892 * OBSOLETE configurations and files
3894 Configurations that have been declared obsolete in this release have
3895 been commented out. Unless there is activity to revive these
3896 configurations, the next release of GDB will have their sources
3897 permanently REMOVED.
3899 AMD 29k family via UDI a29k-amd-udi, udi29k
3900 A29K VxWorks a29k-*-vxworks
3901 AMD 29000 embedded, using EBMON a29k-none-none
3902 AMD 29000 embedded with COFF a29k-none-coff
3903 AMD 29000 embedded with a.out a29k-none-aout
3905 testsuite/gdb.hp/gdb.threads-hp/ directory
3907 * REMOVED configurations and files
3909 TI TMS320C80 tic80-*-*
3911 PowerPC Solaris powerpcle-*-solaris*
3912 PowerPC Windows NT powerpcle-*-cygwin32
3913 PowerPC Netware powerpc-*-netware*
3914 Harris/CXUX m88k m88*-harris-cxux*
3915 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3916 ns32k-utek-sysv* ns32k-utek-*
3917 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3918 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3919 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3920 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3921 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3923 * Changes to command line processing
3925 The new `--args' feature can be used to specify command-line arguments
3926 for the inferior from gdb's command line.
3928 * Changes to key bindings
3930 There is a new `operate-and-get-next' function bound to `C-o'.
3932 *** Changes in GDB 5.1.1
3934 Fix compile problem on DJGPP.
3936 Fix a problem with floating-point registers on the i386 being
3939 Fix to stop GDB crashing on .debug_str debug info.
3941 Numerous documentation fixes.
3943 Numerous testsuite fixes.
3945 *** Changes in GDB 5.1:
3947 * New native configurations
3949 Alpha FreeBSD alpha*-*-freebsd*
3950 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3951 MIPS GNU/Linux mips*-*-linux*
3952 MIPS SGI Irix 6.x mips*-sgi-irix6*
3953 ia64 AIX ia64-*-aix*
3954 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3958 Motorola 68HC11 and 68HC12 m68hc11-elf
3960 UltraSparc running GNU/Linux sparc64-*-linux*
3962 * OBSOLETE configurations and files
3964 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3965 Harris/CXUX m88k m88*-harris-cxux*
3966 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3967 ns32k-utek-sysv* ns32k-utek-*
3968 TI TMS320C80 tic80-*-*
3970 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3971 PowerPC Solaris powerpcle-*-solaris*
3972 PowerPC Windows NT powerpcle-*-cygwin32
3973 PowerPC Netware powerpc-*-netware*
3974 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3975 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3976 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3977 Apple Macintosh (MPW) host N/A
3979 stuff.c (Program to stuff files into a specially prepared space in kdb)
3980 kdb-start.c (Main loop for the standalone kernel debugger)
3982 Configurations that have been declared obsolete in this release have
3983 been commented out. Unless there is activity to revive these
3984 configurations, the next release of GDB will have their sources
3985 permanently REMOVED.
3987 * REMOVED configurations and files
3989 Altos 3068 m68*-altos-*
3990 Convex c1-*-*, c2-*-*
3992 ARM RISCix arm-*-* (as host)
3996 * GDB has been converted to ISO C.
3998 GDB's source code has been converted to ISO C. In particular, the
3999 sources are fully protoized, and rely on standard headers being
4004 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4006 * The MI enabled by default.
4008 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4009 revised and enabled by default. Packages which use GDB as a debugging
4010 engine behind a UI or another front end are encouraged to switch to
4011 using the GDB/MI interface, instead of the old annotations interface
4012 which is now deprecated.
4014 * Support for debugging Pascal programs.
4016 GDB now includes support for debugging Pascal programs. The following
4017 main features are supported:
4019 - Pascal-specific data types such as sets;
4021 - automatic recognition of Pascal sources based on file-name
4024 - Pascal-style display of data types, variables, and functions;
4026 - a Pascal expression parser.
4028 However, some important features are not yet supported.
4030 - Pascal string operations are not supported at all;
4032 - there are some problems with boolean types;
4034 - Pascal type hexadecimal constants are not supported
4035 because they conflict with the internal variables format;
4037 - support for Pascal objects and classes is not full yet;
4039 - unlike Pascal, GDB is case-sensitive for symbol names.
4041 * Changes in completion.
4043 Commands such as `shell', `run' and `set args', which pass arguments
4044 to inferior programs, now complete on file names, similar to what
4045 users expect at the shell prompt.
4047 Commands which accept locations, such as `disassemble', `print',
4048 `breakpoint', `until', etc. now complete on filenames as well as
4049 program symbols. Thus, if you type "break foob TAB", and the source
4050 files linked into the programs include `foobar.c', that file name will
4051 be one of the candidates for completion. However, file names are not
4052 considered for completion after you typed a colon that delimits a file
4053 name from a name of a function in that file, as in "break foo.c:bar".
4055 `set demangle-style' completes on available demangling styles.
4057 * New platform-independent commands:
4059 It is now possible to define a post-hook for a command as well as a
4060 hook that runs before the command. For more details, see the
4061 documentation of `hookpost' in the GDB manual.
4063 * Changes in GNU/Linux native debugging.
4065 Support for debugging multi-threaded programs has been completely
4066 revised for all platforms except m68k and sparc. You can now debug as
4067 many threads as your system allows you to have.
4069 Attach/detach is supported for multi-threaded programs.
4071 Support for SSE registers was added for x86. This doesn't work for
4072 multi-threaded programs though.
4074 * Changes in MIPS configurations.
4076 Multi-arch support is enabled for all MIPS configurations.
4078 GDB can now be built as native debugger on SGI Irix 6.x systems for
4079 debugging n32 executables. (Debugging 64-bit executables is not yet
4082 * Unified support for hardware watchpoints in all x86 configurations.
4084 Most (if not all) native x86 configurations support hardware-assisted
4085 breakpoints and watchpoints in a unified manner. This support
4086 implements debug register sharing between watchpoints, which allows to
4087 put a virtually infinite number of watchpoints on the same address,
4088 and also supports watching regions up to 16 bytes with several debug
4091 The new maintenance command `maintenance show-debug-regs' toggles
4092 debugging print-outs in functions that insert, remove, and test
4093 watchpoints and hardware breakpoints.
4095 * Changes in the DJGPP native configuration.
4097 New command ``info dos sysinfo'' displays assorted information about
4098 the CPU, OS, memory, and DPMI server.
4100 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4101 display information about segment descriptors stored in GDT, LDT, and
4104 New commands ``info dos pde'' and ``info dos pte'' display entries
4105 from Page Directory and Page Tables (for now works with CWSDPMI only).
4106 New command ``info dos address-pte'' displays the Page Table entry for
4107 a given linear address.
4109 GDB can now pass command lines longer than 126 characters to the
4110 program being debugged (requires an update to the libdbg.a library
4111 which is part of the DJGPP development kit).
4113 DWARF2 debug info is now supported.
4115 It is now possible to `step' and `next' through calls to `longjmp'.
4117 * Changes in documentation.
4119 All GDB documentation was converted to GFDL, the GNU Free
4120 Documentation License.
4122 Tracepoints-related commands are now fully documented in the GDB
4125 TUI, the Text-mode User Interface, is now documented in the manual.
4127 Tracepoints-related commands are now fully documented in the GDB
4130 The "GDB Internals" manual now has an index. It also includes
4131 documentation of `ui_out' functions, GDB coding standards, x86
4132 hardware watchpoints, and memory region attributes.
4134 * GDB's version number moved to ``version.in''
4136 The Makefile variable VERSION has been replaced by the file
4137 ``version.in''. People creating GDB distributions should update the
4138 contents of this file.
4142 GUD support is now a standard part of the EMACS distribution.
4144 *** Changes in GDB 5.0:
4146 * Improved support for debugging FP programs on x86 targets
4148 Unified and much-improved support for debugging floating-point
4149 programs on all x86 targets. In particular, ``info float'' now
4150 displays the FP registers in the same format on all x86 targets, with
4151 greater level of detail.
4153 * Improvements and bugfixes in hardware-assisted watchpoints
4155 It is now possible to watch array elements, struct members, and
4156 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4157 on x86 targets no longer erroneously trigger when the address is
4160 * Improvements in the native DJGPP version of GDB
4162 The distribution now includes all the scripts and auxiliary files
4163 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4164 machines ``out of the box''.
4166 The DJGPP version can now debug programs that use signals. It is
4167 possible to catch signals that happened in the debuggee, deliver
4168 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4169 would kill the program being debugged.) Programs that hook hardware
4170 interrupts (keyboard, timer, etc.) can also be debugged.
4172 It is now possible to debug DJGPP programs that redirect their
4173 standard handles or switch them to raw (as opposed to cooked) mode, or
4174 even close them. The command ``run < foo > bar'' works as expected,
4175 and ``info terminal'' reports useful information about the debuggee's
4176 terminal, including raw/cooked mode, redirection, etc.
4178 The DJGPP version now uses termios functions for console I/O, which
4179 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4182 DOS-style file names with drive letters are now fully supported by
4185 It is now possible to debug DJGPP programs that switch their working
4186 directory. It is also possible to rerun the debuggee any number of
4187 times without restarting GDB; thus, you can use the same setup,
4188 breakpoints, etc. for many debugging sessions.
4190 * New native configurations
4192 ARM GNU/Linux arm*-*-linux*
4193 PowerPC GNU/Linux powerpc-*-linux*
4197 Motorola MCore mcore-*-*
4198 x86 VxWorks i[3456]86-*-vxworks*
4199 PowerPC VxWorks powerpc-*-vxworks*
4200 TI TMS320C80 tic80-*-*
4202 * OBSOLETE configurations
4204 Altos 3068 m68*-altos-*
4205 Convex c1-*-*, c2-*-*
4207 ARM RISCix arm-*-* (as host)
4210 Configurations that have been declared obsolete will be commented out,
4211 but the code will be left in place. If there is no activity to revive
4212 these configurations before the next release of GDB, the sources will
4213 be permanently REMOVED.
4215 * Gould support removed
4217 Support for the Gould PowerNode and NP1 has been removed.
4219 * New features for SVR4
4221 On SVR4 native platforms (such as Solaris), if you attach to a process
4222 without first loading a symbol file, GDB will now attempt to locate and
4223 load symbols from the running process's executable file.
4225 * Many C++ enhancements
4227 C++ support has been greatly improved. Overload resolution now works properly
4228 in almost all cases. RTTI support is on the way.
4230 * Remote targets can connect to a sub-program
4232 A popen(3) style serial-device has been added. This device starts a
4233 sub-process (such as a stand-alone simulator) and then communicates
4234 with that. The sub-program to run is specified using the syntax
4235 ``|<program> <args>'' vis:
4237 (gdb) set remotedebug 1
4238 (gdb) target extended-remote |mn10300-elf-sim program-args
4240 * MIPS 64 remote protocol
4242 A long standing bug in the mips64 remote protocol where by GDB
4243 expected certain 32 bit registers (ex SR) to be transfered as 32
4244 instead of 64 bits has been fixed.
4246 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4247 added to provide backward compatibility with older versions of GDB.
4249 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4251 The command ``set remotebinarydownload'' command has been replaced by
4252 ``set remote X-packet''. Other commands in ``set remote'' family
4253 include ``set remote P-packet''.
4255 * Breakpoint commands accept ranges.
4257 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4258 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4259 ``tracepoint passcount'' also accepts a range of tracepoints.
4261 * ``apropos'' command added.
4263 The ``apropos'' command searches through command names and
4264 documentation strings, printing out matches, making it much easier to
4265 try to find a command that does what you are looking for.
4269 A new machine oriented interface (MI) has been added to GDB. This
4270 interface is designed for debug environments running GDB as a separate
4271 process. This is part of the long term libGDB project. See the
4272 "GDB/MI" chapter of the GDB manual for further information. It can be
4273 enabled by configuring with:
4275 .../configure --enable-gdbmi
4277 *** Changes in GDB-4.18:
4279 * New native configurations
4281 HP-UX 10.20 hppa*-*-hpux10.20
4282 HP-UX 11.x hppa*-*-hpux11.0*
4283 M68K GNU/Linux m68*-*-linux*
4287 Fujitsu FR30 fr30-*-elf*
4288 Intel StrongARM strongarm-*-*
4289 Mitsubishi D30V d30v-*-*
4291 * OBSOLETE configurations
4293 Gould PowerNode, NP1 np1-*-*, pn-*-*
4295 Configurations that have been declared obsolete will be commented out,
4296 but the code will be left in place. If there is no activity to revive
4297 these configurations before the next release of GDB, the sources will
4298 be permanently REMOVED.
4302 As a compatibility experiment, GDB's source files buildsym.h and
4303 buildsym.c have been converted to pure standard C, no longer
4304 containing any K&R compatibility code. We believe that all systems in
4305 use today either come with a standard C compiler, or have a GCC port
4306 available. If this is not true, please report the affected
4307 configuration to bug-gdb@gnu.org immediately. See the README file for
4308 information about getting a standard C compiler if you don't have one
4313 GDB now uses readline 2.2.
4315 * set extension-language
4317 You can now control the mapping between filename extensions and source
4318 languages by using the `set extension-language' command. For instance,
4319 you can ask GDB to treat .c files as C++ by saying
4320 set extension-language .c c++
4321 The command `info extensions' lists all of the recognized extensions
4322 and their associated languages.
4324 * Setting processor type for PowerPC and RS/6000
4326 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4327 you can use the `set processor' command to specify what variant of the
4328 PowerPC family you are debugging. The command
4332 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4333 following PowerPC and RS6000 variants:
4335 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4336 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4338 403GC IBM PowerPC 403GC
4339 505 Motorola PowerPC 505
4340 860 Motorola PowerPC 860 or 850
4341 601 Motorola PowerPC 601
4342 602 Motorola PowerPC 602
4343 603 Motorola/IBM PowerPC 603 or 603e
4344 604 Motorola PowerPC 604 or 604e
4345 750 Motorola/IBM PowerPC 750 or 750
4347 At the moment, this command just tells GDB what to name the
4348 special-purpose processor registers. Since almost all the affected
4349 registers are inaccessible to user-level programs, this command is
4350 only useful for remote debugging in its present form.
4354 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4355 more extensive support for HP-UX. Added features include shared
4356 library support, kernel threads and hardware watchpoints for 11.00,
4357 support for HP's ANSI C and C++ compilers, and a compatibility mode
4358 for xdb and dbx commands.
4362 HP's donation includes the new concept of catchpoints, which is a
4363 generalization of the old catch command. On HP-UX, it is now possible
4364 to catch exec, fork, and vfork, as well as library loading.
4366 This means that the existing catch command has changed; its first
4367 argument now specifies the type of catch to be set up. See the
4368 output of "help catch" for a list of catchpoint types.
4370 * Debugging across forks
4372 On HP-UX, you can choose which process to debug when a fork() happens
4377 HP has donated a curses-based terminal user interface (TUI). To get
4378 it, build with --enable-tui. Although this can be enabled for any
4379 configuration, at present it only works for native HP debugging.
4381 * GDB remote protocol additions
4383 A new protocol packet 'X' that writes binary data is now available.
4384 Default behavior is to try 'X', then drop back to 'M' if the stub
4385 fails to respond. The settable variable `remotebinarydownload'
4386 allows explicit control over the use of 'X'.
4388 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4389 full 64-bit address. The command
4391 set remoteaddresssize 32
4393 can be used to revert to the old behaviour. For existing remote stubs
4394 the change should not be noticed, as the additional address information
4397 In order to assist in debugging stubs, you may use the maintenance
4398 command `packet' to send any text string to the stub. For instance,
4400 maint packet heythere
4402 sends the packet "$heythere#<checksum>". Note that it is very easy to
4403 disrupt a debugging session by sending the wrong packet at the wrong
4406 The compare-sections command allows you to compare section data on the
4407 target to what is in the executable file without uploading or
4408 downloading, by comparing CRC checksums.
4410 * Tracing can collect general expressions
4412 You may now collect general expressions at tracepoints. This requires
4413 further additions to the target-side stub; see tracepoint.c and
4414 doc/agentexpr.texi for further details.
4416 * mask-address variable for Mips
4418 For Mips targets, you may control the zeroing of the upper 32 bits of
4419 a 64-bit address by entering `set mask-address on'. This is mainly
4420 of interest to users of embedded R4xxx and R5xxx processors.
4422 * Higher serial baud rates
4424 GDB's serial code now allows you to specify baud rates 57600, 115200,
4425 230400, and 460800 baud. (Note that your host system may not be able
4426 to achieve all of these rates.)
4430 The i960 configuration now includes an initial implementation of a
4431 builtin simulator, contributed by Jim Wilson.
4434 *** Changes in GDB-4.17:
4436 * New native configurations
4438 Alpha GNU/Linux alpha*-*-linux*
4439 Unixware 2.x i[3456]86-unixware2*
4440 Irix 6.x mips*-sgi-irix6*
4441 PowerPC GNU/Linux powerpc-*-linux*
4442 PowerPC Solaris powerpcle-*-solaris*
4443 Sparc GNU/Linux sparc-*-linux*
4444 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4448 Argonaut Risc Chip (ARC) arc-*-*
4449 Hitachi H8/300S h8300*-*-*
4450 Matsushita MN10200 w/simulator mn10200-*-*
4451 Matsushita MN10300 w/simulator mn10300-*-*
4452 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4453 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4454 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4455 Mitsubishi D10V w/simulator d10v-*-*
4456 Mitsubishi M32R/D w/simulator m32r-*-elf*
4457 Tsqware Sparclet sparclet-*-*
4458 NEC V850 w/simulator v850-*-*
4460 * New debugging protocols
4462 ARM with RDI protocol arm*-*-*
4463 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4464 DDB and LSI variants of PMON protocol mips*-*-*
4465 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4466 PowerPC with SDS protocol powerpc{,le}-*-eabi
4467 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4471 All configurations can now understand and use the DWARF 2 debugging
4472 format. The choice is automatic, if the symbol file contains DWARF 2
4477 GDB now includes basic Java language support. This support is
4478 only useful with Java compilers that produce native machine code.
4480 * solib-absolute-prefix and solib-search-path
4482 For SunOS and SVR4 shared libraries, you may now set the prefix for
4483 loading absolute shared library symbol files, and the search path for
4484 locating non-absolute shared library symbol files.
4486 * Live range splitting
4488 GDB can now effectively debug code for which GCC has performed live
4489 range splitting as part of its optimization. See gdb/doc/LRS for
4490 more details on the expected format of the stabs information.
4494 GDB's support for the GNU Hurd, including thread debugging, has been
4495 updated to work with current versions of the Hurd.
4499 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4500 instruction set. ARM GDB automatically detects when Thumb
4501 instructions are in use, and adjusts disassembly and backtracing
4506 GDB's MIPS target configurations now handle the MIP16 16-bit
4511 GDB now includes support for overlays; if an executable has been
4512 linked such that multiple sections are based at the same address, GDB
4513 will decide which section to use for symbolic info. You can choose to
4514 control the decision manually, using overlay commands, or implement
4515 additional target-side support and use "overlay load-target" to bring
4516 in the overlay mapping. Do "help overlay" for more detail.
4520 The command "info symbol <address>" displays information about
4521 the symbol at the specified address.
4525 The standard remote protocol now includes an extension that allows
4526 asynchronous collection and display of trace data. This requires
4527 extensive support in the target-side debugging stub. Tracing mode
4528 includes a new interaction mode in GDB and new commands: see the
4529 file tracepoint.c for more details.
4533 Configurations for embedded MIPS now include a simulator contributed
4534 by Cygnus Solutions. The simulator supports the instruction sets
4535 of most MIPS variants.
4539 Sparc configurations may now include the ERC32 simulator contributed
4540 by the European Space Agency. The simulator is not built into
4541 Sparc targets by default; configure with --enable-sim to include it.
4545 For target configurations that may include multiple variants of a
4546 basic architecture (such as MIPS and SH), you may now set the
4547 architecture explicitly. "set arch" sets, "info arch" lists
4548 the possible architectures.
4550 *** Changes in GDB-4.16:
4552 * New native configurations
4554 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4555 M68K NetBSD m68k-*-netbsd*
4556 PowerPC AIX 4.x powerpc-*-aix*
4557 PowerPC MacOS powerpc-*-macos*
4558 PowerPC Windows NT powerpcle-*-cygwin32
4559 RS/6000 AIX 4.x rs6000-*-aix4*
4563 ARM with RDP protocol arm-*-*
4564 I960 with MON960 i960-*-coff
4565 MIPS VxWorks mips*-*-vxworks*
4566 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4567 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4569 Matra Sparclet sparclet-*-*
4573 The powerpc-eabi configuration now includes the PSIM simulator,
4574 contributed by Andrew Cagney, with assistance from Mike Meissner.
4575 PSIM is a very elaborate model of the PowerPC, including not only
4576 basic instruction set execution, but also details of execution unit
4577 performance and I/O hardware. See sim/ppc/README for more details.
4581 GDB now works with Solaris 2.5.
4583 * Windows 95/NT native
4585 GDB will now work as a native debugger on Windows 95 and Windows NT.
4586 To build it from source, you must use the "gnu-win32" environment,
4587 which uses a DLL to emulate enough of Unix to run the GNU tools.
4588 Further information, binaries, and sources are available at
4589 ftp.cygnus.com, under pub/gnu-win32.
4591 * dont-repeat command
4593 If a user-defined command includes the command `dont-repeat', then the
4594 command will not be repeated if the user just types return. This is
4595 useful if the command is time-consuming to run, so that accidental
4596 extra keystrokes don't run the same command many times.
4598 * Send break instead of ^C
4600 The standard remote protocol now includes an option to send a break
4601 rather than a ^C to the target in order to interrupt it. By default,
4602 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4604 * Remote protocol timeout
4606 The standard remote protocol includes a new variable `remotetimeout'
4607 that allows you to set the number of seconds before GDB gives up trying
4608 to read from the target. The default value is 2.
4610 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4612 By default GDB will automatically keep track of objects as they are
4613 loaded and unloaded by the dynamic linker. By using the command `set
4614 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4615 when shared library events occur, thus allowing you to set breakpoints
4616 in shared libraries which are explicitly loaded by the inferior.
4618 Note this feature does not work on hpux8. On hpux9 you must link
4619 /usr/lib/end.o into your program. This feature should work
4620 automatically on hpux10.
4622 * Irix 5.x hardware watchpoint support
4624 Irix 5 configurations now support the use of hardware watchpoints.
4626 * Mips protocol "SYN garbage limit"
4628 When debugging a Mips target using the `target mips' protocol, you
4629 may set the number of characters that GDB will ignore by setting
4630 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4631 every character. The default value is 1050.
4633 * Recording and replaying remote debug sessions
4635 If you set `remotelogfile' to the name of a file, gdb will write to it
4636 a recording of a remote debug session. This recording may then be
4637 replayed back to gdb using "gdbreplay". See gdbserver/README for
4638 details. This is useful when you have a problem with GDB while doing
4639 remote debugging; you can make a recording of the session and send it
4640 to someone else, who can then recreate the problem.
4642 * Speedups for remote debugging
4644 GDB includes speedups for downloading and stepping MIPS systems using
4645 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4646 and more efficient S-record downloading.
4648 * Memory use reductions and statistics collection
4650 GDB now uses less memory and reports statistics about memory usage.
4651 Try the `maint print statistics' command, for example.
4653 *** Changes in GDB-4.15:
4655 * Psymtabs for XCOFF
4657 The symbol reader for AIX GDB now uses partial symbol tables. This
4658 can greatly improve startup time, especially for large executables.
4660 * Remote targets use caching
4662 Remote targets now use a data cache to speed up communication with the
4663 remote side. The data cache could lead to incorrect results because
4664 it doesn't know about volatile variables, thus making it impossible to
4665 debug targets which use memory mapped I/O devices. `set remotecache
4666 off' turns the the data cache off.
4668 * Remote targets may have threads
4670 The standard remote protocol now includes support for multiple threads
4671 in the target system, using new protocol commands 'H' and 'T'. See
4672 gdb/remote.c for details.
4676 If GDB is configured with `--enable-netrom', then it will include
4677 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4678 acts as though it is a bank of ROM on the target board, but you can
4679 write into it over the network. GDB's support consists only of
4680 support for fast loading into the emulated ROM; to debug, you must use
4681 another protocol, such as standard remote protocol. The usual
4682 sequence is something like
4684 target nrom <netrom-hostname>
4686 target remote <netrom-hostname>:1235
4690 GDB now includes support for the Apple Macintosh, as a host only. It
4691 may be run as either an MPW tool or as a standalone application, and
4692 it can debug through the serial port. All the usual GDB commands are
4693 available, but to the target command, you must supply "serial" as the
4694 device type instead of "/dev/ttyXX". See mpw-README in the main
4695 directory for more information on how to build. The MPW configuration
4696 scripts */mpw-config.in support only a few targets, and only the
4697 mips-idt-ecoff target has been tested.
4701 GDB configuration now uses autoconf. This is not user-visible,
4702 but does simplify configuration and building.
4706 GDB now supports hpux10.
4708 *** Changes in GDB-4.14:
4710 * New native configurations
4712 x86 FreeBSD i[345]86-*-freebsd
4713 x86 NetBSD i[345]86-*-netbsd
4714 NS32k NetBSD ns32k-*-netbsd
4715 Sparc NetBSD sparc-*-netbsd
4719 A29K VxWorks a29k-*-vxworks
4720 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4721 CPU32 EST-300 emulator m68*-*-est*
4722 PowerPC ELF powerpc-*-elf
4725 * Alpha OSF/1 support for procfs
4727 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4728 possible to attach to running processes. As the mounting of the /proc
4729 filesystem is optional on the Alpha, GDB automatically determines
4730 the availability of /proc during startup. This can lead to problems
4731 if /proc is unmounted after GDB has been started.
4733 * Arguments to user-defined commands
4735 User commands may accept up to 10 arguments separated by whitespace.
4736 Arguments are accessed within the user command via $arg0..$arg9. A
4739 print $arg0 + $arg1 + $arg2
4741 To execute the command use:
4744 Defines the command "adder" which prints the sum of its three arguments.
4745 Note the arguments are text substitutions, so they may reference variables,
4746 use complex expressions, or even perform inferior function calls.
4748 * New `if' and `while' commands
4750 This makes it possible to write more sophisticated user-defined
4751 commands. Both commands take a single argument, which is the
4752 expression to evaluate, and must be followed by the commands to
4753 execute, one per line, if the expression is nonzero, the list being
4754 terminated by the word `end'. The `if' command list may include an
4755 `else' word, which causes the following commands to be executed only
4756 if the expression is zero.
4758 * Fortran source language mode
4760 GDB now includes partial support for Fortran 77. It will recognize
4761 Fortran programs and can evaluate a subset of Fortran expressions, but
4762 variables and functions may not be handled correctly. GDB will work
4763 with G77, but does not yet know much about symbols emitted by other
4766 * Better HPUX support
4768 Most debugging facilities now work on dynamic executables for HPPAs
4769 running hpux9 or later. You can attach to running dynamically linked
4770 processes, but by default the dynamic libraries will be read-only, so
4771 for instance you won't be able to put breakpoints in them. To change
4772 that behavior do the following before running the program:
4778 This will cause the libraries to be mapped private and read-write.
4779 To revert to the normal behavior, do this:
4785 You cannot set breakpoints or examine data in the library until after
4786 the library is loaded if the function/data symbols do not have
4789 GDB can now also read debug symbols produced by the HP C compiler on
4790 HPPAs (sorry, no C++, Fortran or 68k support).
4792 * Target byte order now dynamically selectable
4794 You can choose which byte order to use with a target system, via the
4795 commands "set endian big" and "set endian little", and you can see the
4796 current setting by using "show endian". You can also give the command
4797 "set endian auto", in which case GDB will use the byte order
4798 associated with the executable. Currently, only embedded MIPS
4799 configurations support dynamic selection of target byte order.
4801 * New DOS host serial code
4803 This version uses DPMI interrupts to handle buffered I/O, so you
4804 no longer need to run asynctsr when debugging boards connected to
4807 *** Changes in GDB-4.13:
4809 * New "complete" command
4811 This lists all the possible completions for the rest of the line, if it
4812 were to be given as a command itself. This is intended for use by emacs.
4814 * Trailing space optional in prompt
4816 "set prompt" no longer adds a space for you after the prompt you set. This
4817 allows you to set a prompt which ends in a space or one that does not.
4819 * Breakpoint hit counts
4821 "info break" now displays a count of the number of times the breakpoint
4822 has been hit. This is especially useful in conjunction with "ignore"; you
4823 can ignore a large number of breakpoint hits, look at the breakpoint info
4824 to see how many times the breakpoint was hit, then run again, ignoring one
4825 less than that number, and this will get you quickly to the last hit of
4828 * Ability to stop printing at NULL character
4830 "set print null-stop" will cause GDB to stop printing the characters of
4831 an array when the first NULL is encountered. This is useful when large
4832 arrays actually contain only short strings.
4834 * Shared library breakpoints
4836 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4837 breakpoints in shared libraries before the executable is run.
4839 * Hardware watchpoints
4841 There is a new hardware breakpoint for the watch command for sparclite
4842 targets. See gdb/sparclite/hw_breakpoint.note.
4844 Hardware watchpoints are also now supported under GNU/Linux.
4848 Annotations have been added. These are for use with graphical interfaces,
4849 and are still experimental. Currently only gdba.el uses these.
4851 * Improved Irix 5 support
4853 GDB now works properly with Irix 5.2.
4855 * Improved HPPA support
4857 GDB now works properly with the latest GCC and GAS.
4859 * New native configurations
4861 Sequent PTX4 i[34]86-sequent-ptx4
4862 HPPA running OSF/1 hppa*-*-osf*
4863 Atari TT running SVR4 m68*-*-sysv4*
4864 RS/6000 LynxOS rs6000-*-lynxos*
4868 OS/9000 i[34]86-*-os9k
4869 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4872 * Hitachi SH7000 and E7000-PC ICE support
4874 There is now support for communicating with the Hitachi E7000-PC ICE.
4875 This is available automatically when GDB is configured for the SH.
4879 As usual, a variety of small fixes and improvements, both generic
4880 and configuration-specific. See the ChangeLog for more detail.
4882 *** Changes in GDB-4.12:
4884 * Irix 5 is now supported
4888 GDB-4.12 on the HPPA has a number of changes which make it unable
4889 to debug the output from the currently released versions of GCC and
4890 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4891 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4892 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4895 *** Changes in GDB-4.11:
4897 * User visible changes:
4901 The "set remotedebug" option is now consistent between the mips remote
4902 target, remote targets using the gdb-specific protocol, UDI (AMD's
4903 debug protocol for the 29k) and the 88k bug monitor. It is now an
4904 integer specifying a debug level (normally 0 or 1, but 2 means more
4905 debugging info for the mips target).
4907 * DEC Alpha native support
4909 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4910 debug info, but GDB works fairly well with the DEC compiler and should
4911 work with a future GCC release. See the README file for a few
4912 Alpha-specific notes.
4914 * Preliminary thread implementation
4916 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4918 * LynxOS native and target support for 386
4920 This release has been hosted on LynxOS 2.2, and also can be configured
4921 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4924 * Improvements in C++ mangling/demangling.
4926 This release has much better g++ debugging, specifically in name
4927 mangling/demangling, virtual function calls, print virtual table,
4928 call methods, ...etc.
4930 *** Changes in GDB-4.10:
4932 * User visible changes:
4934 Remote debugging using the GDB-specific (`target remote') protocol now
4935 supports the `load' command. This is only useful if you have some
4936 other way of getting the stub to the target system, and you can put it
4937 somewhere in memory where it won't get clobbered by the download.
4939 Filename completion now works.
4941 When run under emacs mode, the "info line" command now causes the
4942 arrow to point to the line specified. Also, "info line" prints
4943 addresses in symbolic form (as well as hex).
4945 All vxworks based targets now support a user settable option, called
4946 vxworks-timeout. This option represents the number of seconds gdb
4947 should wait for responses to rpc's. You might want to use this if
4948 your vxworks target is, perhaps, a slow software simulator or happens
4949 to be on the far side of a thin network line.
4953 This release contains support for using a DEC alpha as a GDB host for
4954 cross debugging. Native alpha debugging is not supported yet.
4957 *** Changes in GDB-4.9:
4961 This is the first GDB release which is accompanied by a matching testsuite.
4962 The testsuite requires installation of dejagnu, which should be available
4963 via ftp from most sites that carry GNU software.
4967 'Cfront' style demangling has had its name changed to 'ARM' style, to
4968 emphasize that it was written from the specifications in the C++ Annotated
4969 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4970 disclaimers, it still generated too much confusion with users attempting to
4971 use gdb with AT&T cfront.
4975 GDB now uses a standard remote interface to a simulator library.
4976 So far, the library contains simulators for the Zilog Z8001/2, the
4977 Hitachi H8/300, H8/500 and Super-H.
4979 * New targets supported
4981 H8/300 simulator h8300-hitachi-hms or h8300hms
4982 H8/500 simulator h8500-hitachi-hms or h8500hms
4983 SH simulator sh-hitachi-hms or sh
4984 Z8000 simulator z8k-zilog-none or z8ksim
4985 IDT MIPS board over serial line mips-idt-ecoff
4987 Cross-debugging to GO32 targets is supported. It requires a custom
4988 version of the i386-stub.c module which is integrated with the
4989 GO32 memory extender.
4991 * New remote protocols
4993 MIPS remote debugging protocol.
4995 * New source languages supported
4997 This version includes preliminary support for Chill, a Pascal like language
4998 used by telecommunications companies. Chill support is also being integrated
4999 into the GNU compiler, but we don't know when it will be publically available.
5002 *** Changes in GDB-4.8:
5004 * HP Precision Architecture supported
5006 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5007 version of this support was available as a set of patches from the
5008 University of Utah. GDB does not support debugging of programs
5009 compiled with the HP compiler, because HP will not document their file
5010 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5011 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5013 Many problems in the preliminary version have been fixed.
5015 * Faster and better demangling
5017 We have improved template demangling and fixed numerous bugs in the GNU style
5018 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5019 character types (wchar_t) are now supported. Demangling of each symbol is now
5020 only done once, and is cached when the symbol table for a file is read in.
5021 This results in a small increase in memory usage for C programs, a moderate
5022 increase in memory usage for C++ programs, and a fantastic speedup in
5025 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5026 from the specifications in the Annotated Reference Manual, which AT&T's
5027 compiler does not actually implement.
5029 * G++ multiple inheritance compiler problem
5031 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5032 inheritance lattices was reworked to properly discover ambiguities. We
5033 recently found an example which causes this new algorithm to fail in a
5034 very subtle way, producing bad debug information for those classes.
5035 The file 'gcc.patch' (in this directory) can be applied to gcc to
5036 circumvent the problem. A future GCC release will contain a complete
5039 The previous G++ debug info problem (mentioned below for the gdb-4.7
5040 release) is fixed in gcc version 2.3.2.
5042 * Improved configure script
5044 The `configure' script will now attempt to guess your system type if
5045 you don't supply a host system type. The old scheme of supplying a
5046 host system triplet is preferable over using this. All the magic is
5047 done in the new `config.guess' script. Examine it for details.
5049 We have also brought our configure script much more in line with the FSF's
5050 version. It now supports the --with-xxx options. In particular,
5051 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5052 The resulting GDB will not be able to read arbitrary object file formats --
5053 only the format ``expected'' to be used on the configured target system.
5054 We hope to make this the default in a future release.
5056 * Documentation improvements
5058 There's new internal documentation on how to modify GDB, and how to
5059 produce clean changes to the code. We implore people to read it
5060 before submitting changes.
5062 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5063 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5064 `info' files are also provided. To build `info' files from scratch,
5065 you will need the latest `makeinfo' release, which will be available in
5066 a future texinfo-X.Y release.
5068 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5069 We're not sure exactly which versions have this problem, but it has
5070 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5071 or better. If that isn't possible, there is a patch in
5072 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5073 around this problem.
5077 GDB now supports array constants that can be used in expressions typed in by
5078 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5079 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5082 The new directory `gdb/sparclite' contains a program that demonstrates
5083 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5085 * New native hosts supported
5087 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5088 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5090 * New targets supported
5092 AMD 29k family via UDI a29k-amd-udi or udi29k
5094 * New file formats supported
5096 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5097 HPUX core files, and SCO 3.2v2 core files.
5101 Attaching to processes now works again; thanks for the many bug reports.
5103 We have also stomped on a bunch of core dumps caused by
5104 printf_filtered("%s") problems.
5106 We eliminated a copyright problem on the rpc and ptrace header files
5107 for VxWorks, which was discovered at the last minute during the 4.7
5108 release. You should now be able to build a VxWorks GDB.
5110 You can now interrupt gdb while an attached process is running. This
5111 will cause the attached process to stop, and give control back to GDB.
5113 We fixed problems caused by using too many file descriptors
5114 for reading symbols from object files and libraries. This was
5115 especially a problem for programs that used many (~100) shared
5118 The `step' command now only enters a subroutine if there is line number
5119 information for the subroutine. Otherwise it acts like the `next'
5120 command. Previously, `step' would enter subroutines if there was
5121 any debugging information about the routine. This avoids problems
5122 when using `cc -g1' on MIPS machines.
5124 * Internal improvements
5126 GDB's internal interfaces have been improved to make it easier to support
5127 debugging of multiple languages in the future.
5129 GDB now uses a common structure for symbol information internally.
5130 Minimal symbols (derived from linkage symbols in object files), partial
5131 symbols (from a quick scan of debug information), and full symbols
5132 contain a common subset of information, making it easier to write
5133 shared code that handles any of them.
5135 * New command line options
5137 We now accept --silent as an alias for --quiet.
5141 The memory-mapped-malloc library is now licensed under the GNU Library
5142 General Public License.
5144 *** Changes in GDB-4.7:
5146 * Host/native/target split
5148 GDB has had some major internal surgery to untangle the support for
5149 hosts and remote targets. Now, when you configure GDB for a remote
5150 target, it will no longer load in all of the support for debugging
5151 local programs on the host. When fully completed and tested, this will
5152 ensure that arbitrary host/target combinations are possible.
5154 The primary conceptual shift is to separate the non-portable code in
5155 GDB into three categories. Host specific code is required any time GDB
5156 is compiled on that host, regardless of the target. Target specific
5157 code relates to the peculiarities of the target, but can be compiled on
5158 any host. Native specific code is everything else: it can only be
5159 built when the host and target are the same system. Child process
5160 handling and core file support are two common `native' examples.
5162 GDB's use of /proc for controlling Unix child processes is now cleaner.
5163 It has been split out into a single module under the `target_ops' vector,
5164 plus two native-dependent functions for each system that uses /proc.
5166 * New hosts supported
5168 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5169 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5170 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5172 * New targets supported
5174 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5175 68030 and CPU32 m68030-*-*, m68332-*-*
5177 * New native hosts supported
5179 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5180 (386bsd is not well tested yet)
5181 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5183 * New file formats supported
5185 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5186 supports reading of `a.out.adobe' object files, which are an a.out
5187 format extended with minimal information about multiple sections.
5191 `show copying' is the same as the old `info copying'.
5192 `show warranty' is the same as `info warrantee'.
5193 These were renamed for consistency. The old commands continue to work.
5195 `info handle' is a new alias for `info signals'.
5197 You can now define pre-command hooks, which attach arbitrary command
5198 scripts to any command. The commands in the hook will be executed
5199 prior to the user's command. You can also create a hook which will be
5200 executed whenever the program stops. See gdb.texinfo.
5204 We now deal with Cfront style name mangling, and can even extract type
5205 info from mangled symbols. GDB can automatically figure out which
5206 symbol mangling style your C++ compiler uses.
5208 Calling of methods and virtual functions has been improved as well.
5212 The crash that occured when debugging Sun Ansi-C compiled binaries is
5213 fixed. This was due to mishandling of the extra N_SO stabs output
5216 We also finally got Ultrix 4.2 running in house, and fixed core file
5217 support, with help from a dozen people on the net.
5219 John M. Farrell discovered that the reason that single-stepping was so
5220 slow on all of the Mips based platforms (primarily SGI and DEC) was
5221 that we were trying to demangle and lookup a symbol used for internal
5222 purposes on every instruction that was being stepped through. Changing
5223 the name of that symbol so that it couldn't be mistaken for a C++
5224 mangled symbol sped things up a great deal.
5226 Rich Pixley sped up symbol lookups in general by getting much smarter
5227 about when C++ symbol mangling is necessary. This should make symbol
5228 completion (TAB on the command line) much faster. It's not as fast as
5229 we'd like, but it's significantly faster than gdb-4.6.
5233 A new user controllable variable 'call_scratch_address' can
5234 specify the location of a scratch area to be used when GDB
5235 calls a function in the target. This is necessary because the
5236 usual method of putting the scratch area on the stack does not work
5237 in systems that have separate instruction and data spaces.
5239 We integrated changes to support the 29k UDI (Universal Debugger
5240 Interface), but discovered at the last minute that we didn't have all
5241 of the appropriate copyright paperwork. We are working with AMD to
5242 resolve this, and hope to have it available soon.
5246 We have sped up the remote serial line protocol, especially for targets
5247 with lots of registers. It now supports a new `expedited status' ('T')
5248 message which can be used in place of the existing 'S' status message.
5249 This allows the remote stub to send only the registers that GDB
5250 needs to make a quick decision about single-stepping or conditional
5251 breakpoints, eliminating the need to fetch the entire register set for
5252 each instruction being stepped through.
5254 The GDB remote serial protocol now implements a write-through cache for
5255 registers, only re-reading the registers if the target has run.
5257 There is also a new remote serial stub for SPARC processors. You can
5258 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5259 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5260 processor with a serial port.
5264 Configure.in files have become much easier to read and modify. A new
5265 `table driven' format makes it more obvious what configurations are
5266 supported, and what files each one uses.
5270 There is a new opcodes library which will eventually contain all of the
5271 disassembly routines and opcode tables. At present, it only contains
5272 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5273 disassembler (binutils/objdump) to share these routines.
5275 The libiberty library is now copylefted under the GNU Library General
5276 Public License. This allows more liberal use, and was done so libg++
5277 can use it. This makes no difference to GDB, since the Library License
5278 grants all the rights from the General Public License.
5282 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5283 reference to the stabs symbol info used by the debugger. It is (as far
5284 as we know) the only published document on this fascinating topic. We
5285 encourage you to read it, compare it to the stabs information on your
5286 system, and send improvements on the document in general (to
5287 bug-gdb@prep.ai.mit.edu).
5289 And, of course, many bugs have been fixed.
5292 *** Changes in GDB-4.6:
5294 * Better support for C++ function names
5296 GDB now accepts as input the "demangled form" of C++ overloaded function
5297 names and member function names, and can do command completion on such names
5298 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5299 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5300 Make use of command completion, it is your friend.
5302 GDB also now accepts a variety of C++ mangled symbol formats. They are
5303 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5304 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5305 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5306 for the list of formats.
5308 * G++ symbol mangling problem
5310 Recent versions of gcc have a bug in how they emit debugging information for
5311 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5312 directory) can be applied to gcc to fix the problem. Alternatively, if you
5313 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5314 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5315 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5318 * New 'maintenance' command
5320 All of the commands related to hacking GDB internals have been moved out of
5321 the main command set, and now live behind the 'maintenance' command. This
5322 can also be abbreviated as 'mt'. The following changes were made:
5324 dump-me -> maintenance dump-me
5325 info all-breakpoints -> maintenance info breakpoints
5326 printmsyms -> maintenance print msyms
5327 printobjfiles -> maintenance print objfiles
5328 printpsyms -> maintenance print psymbols
5329 printsyms -> maintenance print symbols
5331 The following commands are new:
5333 maintenance demangle Call internal GDB demangler routine to
5334 demangle a C++ link name and prints the result.
5335 maintenance print type Print a type chain for a given symbol
5337 * Change to .gdbinit file processing
5339 We now read the $HOME/.gdbinit file before processing the argv arguments
5340 (e.g. reading symbol files or core files). This allows global parameters to
5341 be set, which will apply during the symbol reading. The ./.gdbinit is still
5342 read after argv processing.
5344 * New hosts supported
5346 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5348 GNU/Linux support i386-unknown-linux or linux
5350 We are also including code to support the HP/PA running BSD and HPUX. This
5351 is almost guaranteed not to work, as we didn't have time to test or build it
5352 for this release. We are including it so that the more adventurous (or
5353 masochistic) of you can play with it. We also had major problems with the
5354 fact that the compiler that we got from HP doesn't support the -g option.
5357 * New targets supported
5359 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5361 * More smarts about finding #include files
5363 GDB now remembers the compilation directory for all include files, and for
5364 all files from which C is generated (like yacc and lex sources). This
5365 greatly improves GDB's ability to find yacc/lex sources, and include files,
5366 especially if you are debugging your program from a directory different from
5367 the one that contains your sources.
5369 We also fixed a bug which caused difficulty with listing and setting
5370 breakpoints in include files which contain C code. (In the past, you had to
5371 try twice in order to list an include file that you hadn't looked at before.)
5373 * Interesting infernals change
5375 GDB now deals with arbitrary numbers of sections, where the symbols for each
5376 section must be relocated relative to that section's landing place in the
5377 target's address space. This work was needed to support ELF with embedded
5378 stabs used by Solaris-2.0.
5380 * Bug fixes (of course!)
5382 There have been loads of fixes for the following things:
5383 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5384 i960, stabs, DOS(GO32), procfs, etc...
5386 See the ChangeLog for details.
5388 *** Changes in GDB-4.5:
5390 * New machines supported (host and target)
5392 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5394 SGI Irix-4.x mips-sgi-irix4 or iris4
5396 * New malloc package
5398 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5399 Mmalloc is capable of handling mutiple heaps of memory. It is also
5400 capable of saving a heap to a file, and then mapping it back in later.
5401 This can be used to greatly speedup the startup of GDB by using a
5402 pre-parsed symbol table which lives in a mmalloc managed heap. For
5403 more details, please read mmalloc/mmalloc.texi.
5407 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5408 'help info proc' for details.
5410 * MIPS ecoff symbol table format
5412 The code that reads MIPS symbol table format is now supported on all hosts.
5413 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5416 * File name changes for MS-DOS
5418 Many files in the config directories have been renamed to make it easier to
5419 support GDB on MS-DOSe systems (which have very restrictive file name
5420 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5421 environment) is close to working but has some remaining problems. Note
5422 that debugging of DOS programs is not supported, due to limitations
5423 in the ``operating system'', but it can be used to host cross-debugging.
5425 * Cross byte order fixes
5427 Many fixes have been made to support cross debugging of Sparc and MIPS
5428 targets from hosts whose byte order differs.
5430 * New -mapped and -readnow options
5432 If memory-mapped files are available on your system through the 'mmap'
5433 system call, you can use the -mapped option on the `file' or
5434 `symbol-file' commands to cause GDB to write the symbols from your
5435 program into a reusable file. If the program you are debugging is
5436 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5437 Future GDB debugging sessions will notice the presence of this file,
5438 and will quickly map in symbol information from it, rather than reading
5439 the symbol table from the executable program. Using the '-mapped'
5440 option in a GDB `file' or `symbol-file' command has the same effect as
5441 starting GDB with the '-mapped' command-line option.
5443 You can cause GDB to read the entire symbol table immediately by using
5444 the '-readnow' option with any of the commands that load symbol table
5445 information (or on the GDB command line). This makes the command
5446 slower, but makes future operations faster.
5448 The -mapped and -readnow options are typically combined in order to
5449 build a `fred.syms' file that contains complete symbol information.
5450 A simple GDB invocation to do nothing but build a `.syms' file for future
5453 gdb -batch -nx -mapped -readnow programname
5455 The `.syms' file is specific to the host machine on which GDB is run.
5456 It holds an exact image of GDB's internal symbol table. It cannot be
5457 shared across multiple host platforms.
5459 * longjmp() handling
5461 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5462 siglongjmp() without losing control. This feature has not yet been ported to
5463 all systems. It currently works on many 386 platforms, all MIPS-based
5464 platforms (SGI, DECstation, etc), and Sun3/4.
5468 Preliminary work has been put in to support the new Solaris OS from Sun. At
5469 this time, it can control and debug processes, but it is not capable of
5474 As always, many many bug fixes. The major areas were with g++, and mipsread.
5475 People using the MIPS-based platforms should experience fewer mysterious
5476 crashes and trashed symbol tables.
5478 *** Changes in GDB-4.4:
5480 * New machines supported (host and target)
5482 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5484 BSD Reno on Vax vax-dec-bsd
5485 Ultrix on Vax vax-dec-ultrix
5487 * New machines supported (target)
5489 AMD 29000 embedded, using EBMON a29k-none-none
5493 GDB continues to improve its handling of C++. `References' work better.
5494 The demangler has also been improved, and now deals with symbols mangled as
5495 per the Annotated C++ Reference Guide.
5497 GDB also now handles `stabs' symbol information embedded in MIPS
5498 `ecoff' symbol tables. Since the ecoff format was not easily
5499 extensible to handle new languages such as C++, this appeared to be a
5500 good way to put C++ debugging info into MIPS binaries. This option
5501 will be supported in the GNU C compiler, version 2, when it is
5504 * New features for SVR4
5506 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5507 shared libraries. Debugging dynamically linked programs should present
5508 only minor differences from debugging statically linked programs.
5510 The `info proc' command will print out information about any process
5511 on an SVR4 system (including the one you are debugging). At the moment,
5512 it prints the address mappings of the process.
5514 If you bring up GDB on another SVR4 system, please send mail to
5515 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5517 * Better dynamic linking support in SunOS
5519 Reading symbols from shared libraries which contain debugging symbols
5520 now works properly. However, there remain issues such as automatic
5521 skipping of `transfer vector' code during function calls, which
5522 make it harder to debug code in a shared library, than to debug the
5523 same code linked statically.
5527 GDB is now using the latest `getopt' routines from the FSF. This
5528 version accepts the -- prefix for options with long names. GDB will
5529 continue to accept the old forms (-option and +option) as well.
5530 Various single letter abbreviations for options have been explicity
5531 added to the option table so that they won't get overshadowed in the
5532 future by other options that begin with the same letter.
5536 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5537 Many assorted bugs have been handled. Many more remain to be handled.
5538 See the various ChangeLog files (primarily in gdb and bfd) for details.
5541 *** Changes in GDB-4.3:
5543 * New machines supported (host and target)
5545 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5546 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5547 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5549 * Almost SCO Unix support
5551 We had hoped to support:
5552 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5553 (except for core file support), but we discovered very late in the release
5554 that it has problems with process groups that render gdb unusable. Sorry
5555 about that. I encourage people to fix it and post the fixes.
5557 * Preliminary ELF and DWARF support
5559 GDB can read ELF object files on System V Release 4, and can handle
5560 debugging records for C, in DWARF format, in ELF files. This support
5561 is preliminary. If you bring up GDB on another SVR4 system, please
5562 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5567 GDB now uses the latest `readline' library. One user-visible change
5568 is that two tabs will list possible command completions, which previously
5569 required typing M-? (meta-question mark, or ESC ?).
5573 The `stepi' bug that many of you noticed has been squashed.
5574 Many bugs in C++ have been handled. Many more remain to be handled.
5575 See the various ChangeLog files (primarily in gdb and bfd) for details.
5577 * State of the MIPS world (in case you wondered):
5579 GDB can understand the symbol tables emitted by the compilers
5580 supplied by most vendors of MIPS-based machines, including DEC. These
5581 symbol tables are in a format that essentially nobody else uses.
5583 Some versions of gcc come with an assembler post-processor called
5584 mips-tfile. This program is required if you want to do source-level
5585 debugging of gcc-compiled programs. I believe FSF does not ship
5586 mips-tfile with gcc version 1, but it will eventually come with gcc
5589 Debugging of g++ output remains a problem. g++ version 1.xx does not
5590 really support it at all. (If you're lucky, you should be able to get
5591 line numbers and stack traces to work, but no parameters or local
5592 variables.) With some work it should be possible to improve the
5595 When gcc version 2 is released, you will have somewhat better luck.
5596 However, even then you will get confusing results for inheritance and
5599 We will eventually provide full debugging of g++ output on
5600 DECstations. This will probably involve some kind of stabs-in-ecoff
5601 encapulation, but the details have not been worked out yet.
5604 *** Changes in GDB-4.2:
5606 * Improved configuration
5608 Only one copy of `configure' exists now, and it is not self-modifying.
5609 Porting BFD is simpler.
5613 The `step' and `next' commands now only stop at the first instruction
5614 of a source line. This prevents the multiple stops that used to occur
5615 in switch statements, for-loops, etc. `Step' continues to stop if a
5616 function that has debugging information is called within the line.
5620 Lots of small bugs fixed. More remain.
5622 * New host supported (not target)
5624 Intel 386 PC clone running Mach i386-none-mach
5627 *** Changes in GDB-4.1:
5629 * Multiple source language support
5631 GDB now has internal scaffolding to handle several source languages.
5632 It determines the type of each source file from its filename extension,
5633 and will switch expression parsing and number formatting to match the
5634 language of the function in the currently selected stack frame.
5635 You can also specifically set the language to be used, with
5636 `set language c' or `set language modula-2'.
5640 GDB now has preliminary support for the GNU Modula-2 compiler,
5641 currently under development at the State University of New York at
5642 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5643 continue through the fall of 1991 and into 1992.
5645 Other Modula-2 compilers are currently not supported, and attempting to
5646 debug programs compiled with them will likely result in an error as the
5647 symbol table is read. Feel free to work on it, though!
5649 There are hooks in GDB for strict type checking and range checking,
5650 in the `Modula-2 philosophy', but they do not currently work.
5654 GDB can now write to executable and core files (e.g. patch
5655 a variable's value). You must turn this switch on, specify
5656 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5657 by assigning a new value to a variable. Modifications take
5660 * Automatic SunOS shared library reading
5662 When you run your program, GDB automatically determines where its
5663 shared libraries (if any) have been loaded, and reads their symbols.
5664 The `share' command is no longer needed. This also works when
5665 examining core files.
5669 You can specify the number of lines that the `list' command shows.
5672 * New machines supported (host and target)
5674 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5675 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5676 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5678 * New hosts supported (not targets)
5680 IBM RT/PC: romp-ibm-aix or rtpc
5682 * New targets supported (not hosts)
5684 AMD 29000 embedded with COFF a29k-none-coff
5685 AMD 29000 embedded with a.out a29k-none-aout
5686 Ultracomputer remote kernel debug a29k-nyu-kern
5688 * New remote interfaces
5694 *** Changes in GDB-4.0:
5698 Wide output is wrapped at good places to make the output more readable.
5700 Gdb now supports cross-debugging from a host machine of one type to a
5701 target machine of another type. Communication with the target system
5702 is over serial lines. The ``target'' command handles connecting to the
5703 remote system; the ``load'' command will download a program into the
5704 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5705 also supports debugging of realtime processes running under VxWorks,
5706 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5707 stub on the target system.
5709 New CPUs supported include the AMD 29000 and Intel 960.
5711 GDB now reads object files and symbol tables via a ``binary file''
5712 library, which allows a single copy of GDB to debug programs of multiple
5713 object file types such as a.out and coff.
5715 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5716 refcard.dvi and refcard.ps are available to format it).
5719 * Control-Variable user interface simplified
5721 All variables that control the operation of the debugger can be set
5722 by the ``set'' command, and displayed by the ``show'' command.
5724 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5725 ``Show prompt'' produces the response:
5726 Gdb's prompt is new-gdb=>.
5728 What follows are the NEW set commands. The command ``help set'' will
5729 print a complete list of old and new set commands. ``help set FOO''
5730 will give a longer description of the variable FOO. ``show'' will show
5731 all of the variable descriptions and their current settings.
5733 confirm on/off: Enables warning questions for operations that are
5734 hard to recover from, e.g. rerunning the program while
5735 it is already running. Default is ON.
5737 editing on/off: Enables EMACS style command line editing
5738 of input. Previous lines can be recalled with
5739 control-P, the current line can be edited with control-B,
5740 you can search for commands with control-R, etc.
5743 history filename NAME: NAME is where the gdb command history
5744 will be stored. The default is .gdb_history,
5745 or the value of the environment variable
5748 history size N: The size, in commands, of the command history. The
5749 default is 256, or the value of the environment variable
5752 history save on/off: If this value is set to ON, the history file will
5753 be saved after exiting gdb. If set to OFF, the
5754 file will not be saved. The default is OFF.
5756 history expansion on/off: If this value is set to ON, then csh-like
5757 history expansion will be performed on
5758 command line input. The default is OFF.
5760 radix N: Sets the default radix for input and output. It can be set
5761 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5762 in the current radix, so "set radix 10" is always a no-op.
5764 height N: This integer value is the number of lines on a page. Default
5765 is 24, the current `stty rows'' setting, or the ``li#''
5766 setting from the termcap entry matching the environment
5769 width N: This integer value is the number of characters on a line.
5770 Default is 80, the current `stty cols'' setting, or the ``co#''
5771 setting from the termcap entry matching the environment
5774 Note: ``set screensize'' is obsolete. Use ``set height'' and
5775 ``set width'' instead.
5777 print address on/off: Print memory addresses in various command displays,
5778 such as stack traces and structure values. Gdb looks
5779 more ``symbolic'' if you turn this off; it looks more
5780 ``machine level'' with it on. Default is ON.
5782 print array on/off: Prettyprint arrays. New convenient format! Default
5785 print demangle on/off: Print C++ symbols in "source" form if on,
5788 print asm-demangle on/off: Same, for assembler level printouts
5791 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5794 * Support for Epoch Environment.
5796 The epoch environment is a version of Emacs v18 with windowing. One
5797 new command, ``inspect'', is identical to ``print'', except that if you
5798 are running in the epoch environment, the value is printed in its own
5802 * Support for Shared Libraries
5804 GDB can now debug programs and core files that use SunOS shared libraries.
5805 Symbols from a shared library cannot be referenced
5806 before the shared library has been linked with the program (this
5807 happens after you type ``run'' and before the function main() is entered).
5808 At any time after this linking (including when examining core files
5809 from dynamically linked programs), gdb reads the symbols from each
5810 shared library when you type the ``sharedlibrary'' command.
5811 It can be abbreviated ``share''.
5813 sharedlibrary REGEXP: Load shared object library symbols for files
5814 matching a unix regular expression. No argument
5815 indicates to load symbols for all shared libraries.
5817 info sharedlibrary: Status of loaded shared libraries.
5822 A watchpoint stops execution of a program whenever the value of an
5823 expression changes. Checking for this slows down execution
5824 tremendously whenever you are in the scope of the expression, but is
5825 quite useful for catching tough ``bit-spreader'' or pointer misuse
5826 problems. Some machines such as the 386 have hardware for doing this
5827 more quickly, and future versions of gdb will use this hardware.
5829 watch EXP: Set a watchpoint (breakpoint) for an expression.
5831 info watchpoints: Information about your watchpoints.
5833 delete N: Deletes watchpoint number N (same as breakpoints).
5834 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5835 enable N: Re-enables watchpoint number N (same as breakpoints).
5838 * C++ multiple inheritance
5840 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5843 * C++ exception handling
5845 Gdb now supports limited C++ exception handling. Besides the existing
5846 ability to breakpoint on an exception handler, gdb can breakpoint on
5847 the raising of an exception (before the stack is peeled back to the
5850 catch FOO: If there is a FOO exception handler in the dynamic scope,
5851 set a breakpoint to catch exceptions which may be raised there.
5852 Multiple exceptions (``catch foo bar baz'') may be caught.
5854 info catch: Lists all exceptions which may be caught in the
5855 current stack frame.
5858 * Minor command changes
5860 The command ``call func (arg, arg, ...)'' now acts like the print
5861 command, except it does not print or save a value if the function's result
5862 is void. This is similar to dbx usage.
5864 The ``up'' and ``down'' commands now always print the frame they end up
5865 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5866 frames without printing.
5868 * New directory command
5870 'dir' now adds directories to the FRONT of the source search path.
5871 The path starts off empty. Source files that contain debug information
5872 about the directory in which they were compiled can be found even
5873 with an empty path; Sun CC and GCC include this information. If GDB can't
5874 find your source file in the current directory, type "dir .".
5876 * Configuring GDB for compilation
5878 For normal use, type ``./configure host''. See README or gdb.texinfo
5881 GDB now handles cross debugging. If you are remotely debugging between
5882 two different machines, type ``./configure host -target=targ''.
5883 Host is the machine where GDB will run; targ is the machine
5884 where the program that you are debugging will run.