1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.9
6 * Support for process record-replay and reverse debugging on aarch64*-linux*
7 targets has been added. GDB now supports recording of A64 instruction set
8 including advance SIMD instructions.
10 * Support for Sun's version of the "stabs" debug file format has been removed.
12 * GDB now honors the content of the file /proc/PID/coredump_filter
13 (PID is the process ID) on GNU/Linux systems. This file can be used
14 to specify the types of memory mappings that will be included in a
15 corefile. For more information, please refer to the manual page of
16 "core(5)". GDB also has a new command: "set use-coredump-filter
17 on|off". It allows to set whether GDB will read the content of the
18 /proc/PID/coredump_filter file when generating a corefile.
20 * The "info os" command on GNU/Linux can now display information on
22 "info os cpus" Listing of all cpus/cores on the system
24 * GDB has two new commands: "set serial parity odd|even|none" and
25 "show serial parity". These allows to set or show parity for the
28 * The "info source" command now displays the producer string if it was
29 present in the debug info. This typically includes the compiler version
30 and may include things like its command line arguments.
32 * The "info dll", an alias of the "info sharedlibrary" command,
33 is now available on all platforms.
35 * Directory names supplied to the "set sysroot" commands may be
36 prefixed with "target:" to tell GDB to access shared libraries from
37 the target system, be it local or remote. This replaces the prefix
38 "remote:". The default sysroot has been changed from "" to
39 "target:". "remote:" is automatically converted to "target:" for
40 backward compatibility.
42 * The system root specified by "set sysroot" will be prepended to the
43 filename of the main executable (if reported to GDB as absolute by
44 the operating system) when starting processes remotely, and when
45 attaching to already-running local or remote processes.
47 * GDB now supports automatic location and retrieval of executable
48 files from remote targets. Remote debugging can now be initiated
49 using only a "target remote" or "target extended-remote" command
50 (no "set sysroot" or "file" commands are required). See "New remote
53 * The "dump" command now supports verilog hex format.
55 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
57 * On GNU/Linux, GDB and gdbserver are now able to access executable
58 and shared library files without a "set sysroot" command when
59 attaching to processes running in different mount namespaces from
60 the debugger. This makes it possible to attach to processes in
61 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
62 See "New remote packets" below.
64 * The "tui reg" command now provides completion for all of the
65 available register groups, including target specific groups.
67 * The HISTSIZE environment variable is no longer read when determining
68 the size of GDB's command history. GDB now instead reads the dedicated
69 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
70 disables truncation of command history. Non-numeric values of GDBHISTSIZE
75 ** Memory ports can now be unbuffered.
79 ** gdb.Objfile objects have a new attribute "username",
80 which is the name of the objfile as specified by the user,
81 without, for example, resolving symlinks.
82 ** You can now write frame unwinders in Python.
83 ** gdb.Type objects have a new method "optimized_out",
84 returning optimized out gdb.Value instance of this type.
85 ** gdb.Value objects have new methods "reference_value" and
86 "const_value" which return a reference to the value and a
87 "const" version of the value respectively.
91 maint print symbol-cache
92 Print the contents of the symbol cache.
94 maint print symbol-cache-statistics
95 Print statistics of symbol cache usage.
97 maint flush-symbol-cache
98 Flush the contents of the symbol cache.
102 Start branch trace recording using Branch Trace Store (BTS) format.
105 Evaluate expression by using the compiler and print result.
109 Explicit commands for enabling and disabling tui mode.
112 set mpx bound on i386 and amd64
113 Support for bound table investigation on Intel(R) MPX enabled applications.
117 Start branch trace recording using Intel(R) Processor Trace format.
122 Renamed from "set debug dwarf2-die".
124 Renamed from "show debug dwarf2-die".
127 Renamed from "set debug dwarf2-read".
128 show debug dwarf-read
129 Renamed from "show debug dwarf2-read".
131 maint set dwarf always-disassemble
132 Renamed from "maint set dwarf2 always-disassemble".
133 maint show dwarf always-disassemble
134 Renamed from "maint show dwarf2 always-disassemble".
136 maint set dwarf max-cache-age
137 Renamed from "maint set dwarf2 max-cache-age".
138 maint show dwarf max-cache-age
139 Renamed from "maint show dwarf2 max-cache-age".
142 show debug dwarf-line
143 Control display of debugging info regarding DWARF line processing.
147 Set the maximum number of candidates to be considered during
148 completion. The default value is 200. This limit allows GDB
149 to avoid generating large completion lists, the computation of
150 which can cause the debugger to become temporarily unresponsive.
152 set history remove-duplicates
153 show history remove-duplicates
154 Control the removal of duplicate history entries.
156 maint set symbol-cache-size
157 maint show symbol-cache-size
158 Control the size of the symbol cache.
160 set|show record btrace bts buffer-size
161 Set and show the size of the ring buffer used for branch tracing in
163 The obtained size may differ from the requested size. Use "info
164 record" to see the obtained buffer size.
166 set debug linux-namespaces
167 show debug linux-namespaces
168 Control display of debugging info regarding Linux namespaces.
170 set|show record btrace pt buffer-size
171 Set and show the size of the ring buffer used for branch tracing in
172 Intel(R) Processor Trace format.
173 The obtained size may differ from the requested size. Use "info
174 record" to see the obtained buffer size.
176 * The command 'thread apply all' can now support new option '-ascending'
177 to call its specified command for all threads in ascending order.
179 * Python/Guile scripting
181 ** GDB now supports auto-loading of Python/Guile scripts contained in the
182 special section named `.debug_gdb_scripts'.
186 qXfer:btrace-conf:read
187 Return the branch trace configuration for the current thread.
189 Qbtrace-conf:bts:size
190 Set the requested ring buffer size for branch tracing in BTS format.
193 Enable Intel(R) Procesor Trace-based branch tracing for the current
194 process. The remote stub reports support for this packet to GDB's
198 Set the requested ring buffer size for branch tracing in Intel(R) Processor
202 Indicates a memory breakpoint instruction was executed, irrespective
203 of whether it was GDB that planted the breakpoint or the breakpoint
204 is hardcoded in the program. This is required for correct non-stop
208 Indicates the target stopped for a hardware breakpoint. This is
209 required for correct non-stop mode operation.
212 Return information about files on the remote system.
215 Return the full absolute name of the file that was executed to
216 create a process running on the remote system.
219 Select the filesystem on which vFile: operations with filename
220 arguments will operate. This is required for GDB to be able to
221 access files on remote targets where the remote stub does not
222 share a common filesystem with the inferior(s).
225 Indicates that a fork system call was executed.
228 Indicates that a vfork system call was executed.
230 vforkdone stop reason
231 Indicates that a vfork child of the specified process has executed
232 an exec or exit, allowing the vfork parent to resume execution.
234 fork-events and vfork-events features in qSupported
235 The qSupported packet allows GDB to request support for fork and
236 vfork events using new 'gdbfeatures' fork-events and vfork-events,
237 and the qSupported response can contain the corresponding
238 'stubfeatures'. Set and show commands can be used to display
239 whether these features are enabled.
241 * Extended-remote fork events
243 ** GDB now has support for fork events on extended-remote Linux
244 targets. For targets with Linux kernels 2.5.60 and later, this
245 enables follow-fork-mode and detach-on-fork for both fork and
246 vfork, as well as fork and vfork catchpoints.
248 * The info record command now shows the recording format and the
249 branch tracing configuration for the current thread when using
250 the btrace record target.
251 For the BTS format, it shows the ring buffer size.
253 * GDB now has support for DTrace USDT (Userland Static Defined
254 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
256 * GDB now supports access to vector registers on S/390 GNU/Linux
259 * Removed command line options
261 -xdb HP-UX XDB compatibility mode.
263 * Removed targets and native configurations
265 HP/PA running HP-UX hppa*-*-hpux*
266 Itanium running HP-UX ia64-*-hpux*
268 * New configure options
271 This configure option allows the user to build GDB with support for
272 Intel(R) Processor Trace (default: auto). This requires libipt.
274 --with-libipt-prefix=PATH
275 Specify the path to the version of libipt that GDB should use.
276 $PATH/include should contain the intel-pt.h header and
277 $PATH/lib should contain the libipt.so library.
279 *** Changes in GDB 7.9.1
283 ** Xmethods can now specify a result type.
285 *** Changes in GDB 7.9
287 * GDB now supports hardware watchpoints on x86 GNU Hurd.
291 ** You can now access frame registers from Python scripts.
292 ** New attribute 'producer' for gdb.Symtab objects.
293 ** gdb.Objfile objects have a new attribute "progspace",
294 which is the gdb.Progspace object of the containing program space.
295 ** gdb.Objfile objects have a new attribute "owner".
296 ** gdb.Objfile objects have a new attribute "build_id",
297 which is the build ID generated when the file was built.
298 ** gdb.Objfile objects have a new method "add_separate_debug_file".
299 ** A new event "gdb.clear_objfiles" has been added, triggered when
300 selecting a new file to debug.
301 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
302 ** New function gdb.lookup_objfile.
304 New events which are triggered when GDB modifies the state of the
307 ** gdb.events.inferior_call_pre: Function call is about to be made.
308 ** gdb.events.inferior_call_post: Function call has just been made.
309 ** gdb.events.memory_changed: A memory location has been altered.
310 ** gdb.events.register_changed: A register has been altered.
312 * New Python-based convenience functions:
314 ** $_caller_is(name [, number_of_frames])
315 ** $_caller_matches(regexp [, number_of_frames])
316 ** $_any_caller_is(name [, number_of_frames])
317 ** $_any_caller_matches(regexp [, number_of_frames])
319 * GDB now supports the compilation and injection of source code into
320 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
321 to compile the source code to object code, and if successful, inject
322 and execute that code within the current context of the inferior.
323 Currently the C language is supported. The commands used to
324 interface with this new feature are:
326 compile code [-raw|-r] [--] [source code]
327 compile file [-raw|-r] filename
331 demangle [-l language] [--] name
332 Demangle "name" in the specified language, or the current language
333 if elided. This command is renamed from the "maint demangle" command.
334 The latter is kept as a no-op to avoid "maint demangle" being interpreted
335 as "maint demangler-warning".
337 queue-signal signal-name-or-number
338 Queue a signal to be delivered to the thread when it is resumed.
340 add-auto-load-scripts-directory directory
341 Add entries to the list of directories from which to load auto-loaded
344 maint print user-registers
345 List all currently available "user" registers.
347 compile code [-r|-raw] [--] [source code]
348 Compile, inject, and execute in the inferior the executable object
349 code produced by compiling the provided source code.
351 compile file [-r|-raw] filename
352 Compile and inject into the inferior the executable object code
353 produced by compiling the source code stored in the filename
356 * On resume, GDB now always passes the signal the program had stopped
357 for to the thread the signal was sent to, even if the user changed
358 threads before resuming. Previously GDB would often (but not
359 always) deliver the signal to the thread that happens to be current
362 * Conversely, the "signal" command now consistently delivers the
363 requested signal to the current thread. GDB now asks for
364 confirmation if the program had stopped for a signal and the user
365 switched threads meanwhile.
367 * "breakpoint always-inserted" modes "off" and "auto" merged.
369 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
370 won't remove breakpoints from the target until all threads stop,
371 even in non-stop mode. The "auto" mode has been removed, and "off"
372 is now the default mode.
376 set debug symbol-lookup
377 show debug symbol-lookup
378 Control display of debugging info regarding symbol lookup.
382 ** The -list-thread-groups command outputs an exit-code field for
383 inferiors that have exited.
387 MIPS SDE mips*-sde*-elf*
391 Support for these obsolete configurations has been removed.
393 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
394 SGI Irix-5.x mips-*-irix5*
395 SGI Irix-6.x mips-*-irix6*
396 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
397 VAX running Ultrix vax-*-ultrix*
399 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
400 and "assf"), have been removed. Use the "sharedlibrary" command, or
401 its alias "share", instead.
403 *** Changes in GDB 7.8
405 * New command line options
408 This is an alias for the --data-directory option.
410 * GDB supports printing and modifying of variable length automatic arrays
411 as specified in ISO C99.
413 * The ARM simulator now supports instruction level tracing
414 with or without disassembly.
418 GDB now has support for scripting using Guile. Whether this is
419 available is determined at configure time.
420 Guile version 2.0 or greater is required.
421 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
423 * New commands (for set/show, see "New options" below)
427 Invoke CODE by passing it to the Guile interpreter.
431 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
433 info auto-load guile-scripts [regexp]
434 Print the list of automatically loaded Guile scripts.
436 * The source command is now capable of sourcing Guile scripts.
437 This feature is dependent on the debugger being built with Guile support.
441 set print symbol-loading (off|brief|full)
442 show print symbol-loading
443 Control whether to print informational messages when loading symbol
444 information for a file. The default is "full", but when debugging
445 programs with large numbers of shared libraries the amount of output
448 set guile print-stack (none|message|full)
449 show guile print-stack
450 Show a stack trace when an error is encountered in a Guile script.
452 set auto-load guile-scripts (on|off)
453 show auto-load guile-scripts
454 Control auto-loading of Guile script files.
456 maint ada set ignore-descriptive-types (on|off)
457 maint ada show ignore-descriptive-types
458 Control whether the debugger should ignore descriptive types in Ada
459 programs. The default is not to ignore the descriptive types. See
460 the user manual for more details on descriptive types and the intended
461 usage of this option.
463 set auto-connect-native-target
465 Control whether GDB is allowed to automatically connect to the
466 native target for the run, attach, etc. commands when not connected
467 to any target yet. See also "target native" below.
469 set record btrace replay-memory-access (read-only|read-write)
470 show record btrace replay-memory-access
471 Control what memory accesses are allowed during replay.
473 maint set target-async (on|off)
474 maint show target-async
475 This controls whether GDB targets operate in synchronous or
476 asynchronous mode. Normally the default is asynchronous, if it is
477 available; but this can be changed to more easily debug problems
478 occurring only in synchronous mode.
480 set mi-async (on|off)
482 Control whether MI asynchronous mode is preferred. This supersedes
483 "set target-async" of previous GDB versions.
485 * "set target-async" is deprecated as a CLI option and is now an alias
486 for "set mi-async" (only puts MI into async mode).
488 * Background execution commands (e.g., "c&", "s&", etc.) are now
489 possible ``out of the box'' if the target supports them. Previously
490 the user would need to explicitly enable the possibility with the
491 "set target-async on" command.
493 * New features in the GDB remote stub, GDBserver
495 ** New option --debug-format=option1[,option2,...] allows one to add
496 additional text to each output. At present only timestamps
497 are supported: --debug-format=timestamps.
498 Timestamps can also be turned on with the
499 "monitor set debug-format timestamps" command from GDB.
501 * The 'record instruction-history' command now starts counting instructions
502 at one. This also affects the instruction ranges reported by the
503 'record function-call-history' command when given the /i modifier.
505 * The command 'record function-call-history' supports a new modifier '/c' to
506 indent the function names based on their call stack depth.
507 The fields for the '/i' and '/l' modifier have been reordered.
508 The source line range is now prefixed with 'at'.
509 The instruction range is now prefixed with 'inst'.
510 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
511 "record instruction-history" and "list" commands.
513 * The ranges given as arguments to the 'record function-call-history' and
514 'record instruction-history' commands are now inclusive.
516 * The btrace record target now supports the 'record goto' command.
517 For locations inside the execution trace, the back trace is computed
518 based on the information stored in the execution trace.
520 * The btrace record target supports limited reverse execution and replay.
521 The target does not record data and therefore does not allow reading
524 * The "catch syscall" command now works on s390*-linux* targets.
526 * The "compare-sections" command is no longer specific to target
527 remote. It now works with all targets.
529 * All native targets are now consistently called "native".
530 Consequently, the "target child", "target GNU", "target djgpp",
531 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
532 commands have been replaced with "target native". The QNX/NTO port
533 leaves the "procfs" target in place and adds a "native" target for
534 consistency with other ports. The impact on users should be minimal
535 as these commands previously either throwed an error, or were
536 no-ops. The target's name is visible in the output of the following
537 commands: "help target", "info target", "info files", "maint print
540 * The "target native" command now connects to the native target. This
541 can be used to launch native programs even when "set
542 auto-connect-native-target" is set to off.
544 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
546 * Support for Intel(R) AVX-512 registers on GNU/Linux.
547 Support displaying and modifying Intel(R) AVX-512 registers
548 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
552 qXfer:btrace:read's annex
553 The qXfer:btrace:read packet supports a new annex 'delta' to read
554 branch trace incrementally.
558 ** Valid Python operations on gdb.Value objects representing
559 structs/classes invoke the corresponding overloaded operators if
561 ** New `Xmethods' feature in the Python API. Xmethods are
562 additional methods or replacements for existing methods of a C++
563 class. This feature is useful for those cases where a method
564 defined in C++ source code could be inlined or optimized out by
565 the compiler, making it unavailable to GDB.
568 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
570 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
571 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
572 its alias "share", instead.
574 * The commands "set remotebaud" and "show remotebaud" are no longer
575 supported. Use "set serial baud" and "show serial baud" (respectively)
580 ** A new option "-gdb-set mi-async" replaces "-gdb-set
581 target-async". The latter is left as a deprecated alias of the
582 former for backward compatibility. If the target supports it,
583 CLI background execution commands are now always possible by
584 default, independently of whether the frontend stated a
585 preference for asynchronous execution with "-gdb-set mi-async".
586 Previously "-gdb-set target-async off" affected both MI execution
587 commands and CLI execution commands.
589 *** Changes in GDB 7.7
591 * Improved support for process record-replay and reverse debugging on
592 arm*-linux* targets. Support for thumb32 and syscall instruction
593 recording has been added.
595 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
597 * GDB now supports Fission DWP file format version 2.
598 http://gcc.gnu.org/wiki/DebugFission
600 * New convenience function "$_isvoid", to check whether an expression
601 is void. A void expression is an expression where the type of the
602 result is "void". For example, some convenience variables may be
603 "void" when evaluated (e.g., "$_exitcode" before the execution of
604 the program being debugged; or an undefined convenience variable).
605 Another example, when calling a function whose return type is
608 * The "maintenance print objfiles" command now takes an optional regexp.
610 * The "catch syscall" command now works on arm*-linux* targets.
612 * GDB now consistently shows "<not saved>" when printing values of
613 registers the debug info indicates have not been saved in the frame
614 and there's nowhere to retrieve them from
615 (callee-saved/call-clobbered registers):
620 (gdb) info registers rax
623 Before, the former would print "<optimized out>", and the latter
624 "*value not available*".
626 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
631 ** Frame filters and frame decorators have been added.
632 ** Temporary breakpoints are now supported.
633 ** Line tables representation has been added.
634 ** New attribute 'parent_type' for gdb.Field objects.
635 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
636 ** New attribute 'name' for gdb.Type objects.
640 Nios II ELF nios2*-*-elf
641 Nios II GNU/Linux nios2*-*-linux
642 Texas Instruments MSP430 msp430*-*-elf
644 * Removed native configurations
646 Support for these a.out NetBSD and OpenBSD obsolete configurations has
647 been removed. ELF variants of these configurations are kept supported.
649 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
650 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
651 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
652 i[34567]86-*-openbsd3.[0-3]
653 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
654 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
655 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
659 Like "catch throw", but catches a re-thrown exception.
661 Renamed from old "maint check-symtabs".
663 Perform consistency checks on symtabs.
665 Expand symtabs matching an optional regexp.
668 Display the details of GDB configure-time options.
670 maint set|show per-command
671 maint set|show per-command space
672 maint set|show per-command time
673 maint set|show per-command symtab
674 Enable display of per-command gdb resource usage.
676 remove-symbol-file FILENAME
677 remove-symbol-file -a ADDRESS
678 Remove a symbol file added via add-symbol-file. The file to remove
679 can be identified by its filename or by an address that lies within
680 the boundaries of this symbol file in memory.
683 info exceptions REGEXP
684 Display the list of Ada exceptions defined in the program being
685 debugged. If provided, only the exceptions whose names match REGEXP
690 set debug symfile off|on
692 Control display of debugging info regarding reading symbol files and
693 symbol tables within those files
695 set print raw frame-arguments
696 show print raw frame-arguments
697 Set/show whether to print frame arguments in raw mode,
698 disregarding any defined pretty-printers.
700 set remote trace-status-packet
701 show remote trace-status-packet
702 Set/show the use of remote protocol qTStatus packet.
706 Control display of debugging messages related to Nios II targets.
710 Control whether target-assisted range stepping is enabled.
712 set startup-with-shell
713 show startup-with-shell
714 Specifies whether Unix child processes are started via a shell or
719 Use the target memory cache for accesses to the code segment. This
720 improves performance of remote debugging (particularly disassembly).
722 * You can now use a literal value 'unlimited' for options that
723 interpret 0 or -1 as meaning "unlimited". E.g., "set
724 trace-buffer-size unlimited" is now an alias for "set
725 trace-buffer-size -1" and "set height unlimited" is now an alias for
728 * The "set debug symtab-create" debugging option of GDB has been changed to
729 accept a verbosity level. 0 means "off", 1 provides basic debugging
730 output, and values of 2 or greater provides more verbose output.
732 * New command-line options
734 Display the details of GDB configure-time options.
736 * The command 'tsave' can now support new option '-ctf' to save trace
737 buffer in Common Trace Format.
739 * Newly installed $prefix/bin/gcore acts as a shell interface for the
742 * GDB now implements the the C++ 'typeid' operator.
744 * The new convenience variable $_exception holds the exception being
745 thrown or caught at an exception-related catchpoint.
747 * The exception-related catchpoints, like "catch throw", now accept a
748 regular expression which can be used to filter exceptions by type.
750 * The new convenience variable $_exitsignal is automatically set to
751 the terminating signal number when the program being debugged dies
752 due to an uncaught signal.
756 ** All MI commands now accept an optional "--language" option.
757 Support for this feature can be verified by using the "-list-features"
758 command, which should contain "language-option".
760 ** The new command -info-gdb-mi-command allows the user to determine
761 whether a GDB/MI command is supported or not.
763 ** The "^error" result record returned when trying to execute an undefined
764 GDB/MI command now provides a variable named "code" whose content is the
765 "undefined-command" error code. Support for this feature can be verified
766 by using the "-list-features" command, which should contain
767 "undefined-command-error-code".
769 ** The -trace-save MI command can optionally save trace buffer in Common
772 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
774 ** The command -data-list-register-values now accepts an optional
775 "--skip-unavailable" option. When used, only the available registers
778 ** The new command -trace-frame-collected dumps collected variables,
779 computed expressions, tvars, memory and registers in a traceframe.
781 ** The commands -stack-list-locals, -stack-list-arguments and
782 -stack-list-variables now accept an option "--skip-unavailable".
783 When used, only the available locals or arguments are displayed.
785 ** The -exec-run command now accepts an optional "--start" option.
786 When used, the command follows the same semantics as the "start"
787 command, stopping the program's execution at the start of its
788 main subprogram. Support for this feature can be verified using
789 the "-list-features" command, which should contain
790 "exec-run-start-option".
792 ** The new commands -catch-assert and -catch-exceptions insert
793 catchpoints stopping the program when Ada exceptions are raised.
795 ** The new command -info-ada-exceptions provides the equivalent of
796 the new "info exceptions" command.
798 * New system-wide configuration scripts
799 A GDB installation now provides scripts suitable for use as system-wide
800 configuration scripts for the following systems:
804 * GDB now supports target-assigned range stepping with remote targets.
805 This improves the performance of stepping source lines by reducing
806 the number of control packets from/to GDB. See "New remote packets"
809 * GDB now understands the element 'tvar' in the XML traceframe info.
810 It has the id of the collected trace state variables.
812 * On S/390 targets that provide the transactional-execution feature,
813 the program interruption transaction diagnostic block (TDB) is now
814 represented as a number of additional "registers" in GDB.
820 The vCont packet supports a new 'r' action, that tells the remote
821 stub to step through an address range itself, without GDB
822 involvemement at each single-step.
824 qXfer:libraries-svr4:read's annex
825 The previously unused annex of the qXfer:libraries-svr4:read packet
826 is now used to support passing an argument list. The remote stub
827 reports support for this argument list to GDB's qSupported query.
828 The defined arguments are "start" and "prev", used to reduce work
829 necessary for library list updating, resulting in significant
832 * New features in the GDB remote stub, GDBserver
834 ** GDBserver now supports target-assisted range stepping. Currently
835 enabled on x86/x86_64 GNU/Linux targets.
837 ** GDBserver now adds element 'tvar' in the XML in the reply to
838 'qXfer:traceframe-info:read'. It has the id of the collected
839 trace state variables.
841 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
844 * New 'z' formatter for printing and examining memory, this displays the
845 value as hexadecimal zero padded on the left to the size of the type.
847 * GDB can now use Windows x64 unwinding data.
849 * The "set remotebaud" command has been replaced by "set serial baud".
850 Similarly, "show remotebaud" has been replaced by "show serial baud".
851 The "set remotebaud" and "show remotebaud" commands are still available
852 to provide backward compatibility with older versions of GDB.
854 *** Changes in GDB 7.6
856 * Target record has been renamed to record-full.
857 Record/replay is now enabled with the "record full" command.
858 This also affects settings that are associated with full record/replay
859 that have been moved from "set/show record" to "set/show record full":
861 set|show record full insn-number-max
862 set|show record full stop-at-limit
863 set|show record full memory-query
865 * A new record target "record-btrace" has been added. The new target
866 uses hardware support to record the control-flow of a process. It
867 does not support replaying the execution, but it implements the
868 below new commands for investigating the recorded execution log.
869 This new recording method can be enabled using:
873 The "record-btrace" target is only available on Intel Atom processors
874 and requires a Linux kernel 2.6.32 or later.
876 * Two new commands have been added for record/replay to give information
877 about the recorded execution without having to replay the execution.
878 The commands are only supported by "record btrace".
880 record instruction-history prints the execution history at
881 instruction granularity
883 record function-call-history prints the execution history at
886 * New native configurations
888 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
889 FreeBSD/powerpc powerpc*-*-freebsd
890 x86_64/Cygwin x86_64-*-cygwin*
891 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
895 ARM AArch64 aarch64*-*-elf
896 ARM AArch64 GNU/Linux aarch64*-*-linux
897 Lynx 178 PowerPC powerpc-*-lynx*178
898 x86_64/Cygwin x86_64-*-cygwin*
899 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
901 * If the configured location of system.gdbinit file (as given by the
902 --with-system-gdbinit option at configure time) is in the
903 data-directory (as specified by --with-gdb-datadir at configure
904 time) or in one of its subdirectories, then GDB will look for the
905 system-wide init file in the directory specified by the
906 --data-directory command-line option.
908 * New command line options:
910 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
911 other initialization files, unlike -nx which disables all of them.
913 * Removed command line options
915 -epoch This was used by the gdb mode in Epoch, an ancient fork of
918 * The 'ptype' and 'whatis' commands now accept an argument to control
921 * 'info proc' now works on some core files.
925 ** Vectors can be created with gdb.Type.vector.
927 ** Python's atexit.register now works in GDB.
929 ** Types can be pretty-printed via a Python API.
931 ** Python 3 is now supported (in addition to Python 2.4 or later)
933 ** New class gdb.Architecture exposes GDB's internal representation
934 of architecture in the Python API.
936 ** New method Frame.architecture returns the gdb.Architecture object
937 corresponding to the frame's architecture.
939 * New Python-based convenience functions:
941 ** $_memeq(buf1, buf2, length)
942 ** $_streq(str1, str2)
944 ** $_regex(str, regex)
946 * The 'cd' command now defaults to using '~' (the home directory) if not
949 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
950 default for GCC since November 2000.
952 * The command 'forward-search' can now be abbreviated as 'fo'.
954 * The command 'info tracepoints' can now display 'installed on target'
955 or 'not installed on target' for each non-pending location of tracepoint.
957 * New configure options
959 --enable-libmcheck/--disable-libmcheck
960 By default, development versions are built with -lmcheck on hosts
961 that support it, in order to help track memory corruption issues.
962 Release versions, on the other hand, are built without -lmcheck
963 by default. The --enable-libmcheck/--disable-libmcheck configure
964 options allow the user to override that default.
965 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
966 This configure option allows the user to build GDB with
967 libbabeltrace using which GDB can read Common Trace Format data.
969 * New commands (for set/show, see "New options" below)
972 Catch signals. This is similar to "handle", but allows commands and
973 conditions to be attached.
976 List the BFDs known to GDB.
978 python-interactive [command]
980 Start a Python interactive prompt, or evaluate the optional command
981 and print the result of expressions.
984 "py" is a new alias for "python".
986 enable type-printer [name]...
987 disable type-printer [name]...
988 Enable or disable type printers.
992 ** For the Renesas Super-H architecture, the "regs" command has been removed
993 (has been deprecated in GDB 7.5), and "info all-registers" should be used
998 set print type methods (on|off)
999 show print type methods
1000 Control whether method declarations are displayed by "ptype".
1001 The default is to show them.
1003 set print type typedefs (on|off)
1004 show print type typedefs
1005 Control whether typedef definitions are displayed by "ptype".
1006 The default is to show them.
1008 set filename-display basename|relative|absolute
1009 show filename-display
1010 Control the way in which filenames is displayed.
1011 The default is "relative", which preserves previous behavior.
1013 set trace-buffer-size
1014 show trace-buffer-size
1015 Request target to change the size of trace buffer.
1017 set remote trace-buffer-size-packet auto|on|off
1018 show remote trace-buffer-size-packet
1019 Control the use of the remote protocol `QTBuffer:size' packet.
1023 Control display of debugging messages related to ARM AArch64.
1026 set debug coff-pe-read
1027 show debug coff-pe-read
1028 Control display of debugging messages related to reading of COFF/PE
1033 Control display of debugging messages related to Mach-O symbols
1036 set debug notification
1037 show debug notification
1038 Control display of debugging info for async remote notification.
1042 ** Command parameter changes are now notified using new async record
1043 "=cmd-param-changed".
1044 ** Trace frame changes caused by command "tfind" are now notified using
1045 new async record "=traceframe-changed".
1046 ** The creation, deletion and modification of trace state variables
1047 are now notified using new async records "=tsv-created",
1048 "=tsv-deleted" and "=tsv-modified".
1049 ** The start and stop of process record are now notified using new
1050 async record "=record-started" and "=record-stopped".
1051 ** Memory changes are now notified using new async record
1053 ** The data-disassemble command response will include a "fullname" field
1054 containing the absolute file name when source has been requested.
1055 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1056 command, to allow pattern filling of memory areas.
1057 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1058 library load/unload events.
1059 ** The response to breakpoint commands and breakpoint async records
1060 includes an "installed" field containing a boolean state about each
1061 non-pending tracepoint location is whether installed on target or not.
1062 ** Output of the "-trace-status" command includes a "trace-file" field
1063 containing the name of the trace file being examined. This field is
1064 optional, and only present when examining a trace file.
1065 ** The "fullname" field is now always present along with the "file" field,
1066 even if the file cannot be found by GDB.
1068 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1069 You must have the LZMA library available when configuring GDB for this
1070 feature to be enabled. For more information, see:
1071 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1073 * New remote packets
1076 Set the size of trace buffer. The remote stub reports support for this
1077 packet to gdb's qSupported query.
1080 Enable Branch Trace Store (BTS)-based branch tracing for the current
1081 thread. The remote stub reports support for this packet to gdb's
1085 Disable branch tracing for the current thread. The remote stub reports
1086 support for this packet to gdb's qSupported query.
1089 Read the traced branches for the current thread. The remote stub
1090 reports support for this packet to gdb's qSupported query.
1092 *** Changes in GDB 7.5
1094 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1095 for more x32 ABI info.
1097 * GDB now supports access to MIPS DSP registers on Linux targets.
1099 * GDB now supports debugging microMIPS binaries.
1101 * The "info os" command on GNU/Linux can now display information on
1102 several new classes of objects managed by the operating system:
1103 "info os procgroups" lists process groups
1104 "info os files" lists file descriptors
1105 "info os sockets" lists internet-domain sockets
1106 "info os shm" lists shared-memory regions
1107 "info os semaphores" lists semaphores
1108 "info os msg" lists message queues
1109 "info os modules" lists loaded kernel modules
1111 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1112 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1113 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1114 options and inspect the probe arguments using the new $_probe_arg family
1115 of convenience variables. You can obtain more information about SystemTap
1116 in <http://sourceware.org/systemtap/>.
1118 * GDB now supports reversible debugging on ARM, it allows you to
1119 debug basic ARM and THUMB instructions, and provides
1120 record/replay support.
1122 * The option "symbol-reloading" has been deleted as it is no longer used.
1126 ** GDB commands implemented in Python can now be put in command class
1129 ** The "maint set python print-stack on|off" is now deleted.
1131 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1132 apply "flag enum"-style pretty-printing to any enum.
1134 ** gdb.lookup_symbol can now work when there is no current frame.
1136 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1137 the source at which the symbol was defined.
1139 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1140 method 'value'. The former indicates whether the symbol needs a
1141 frame in order to compute its value, and the latter computes the
1144 ** A new method 'referenced_value' on gdb.Value objects which can
1145 dereference pointer as well as C++ reference values.
1147 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1148 which return the global and static blocks (as gdb.Block objects),
1149 of the underlying symbol table, respectively.
1151 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1152 object associated with a PC value.
1154 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1155 of the address range occupied by code for the current source line.
1157 * Go language support.
1158 GDB now supports debugging programs written in the Go programming
1161 * GDBserver now supports stdio connections.
1162 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1164 * The binary "gdbtui" can no longer be built or installed.
1165 Use "gdb -tui" instead.
1167 * GDB will now print "flag" enums specially. A flag enum is one where
1168 all the enumerator values have no bits in common when pairwise
1169 "and"ed. When printing a value whose type is a flag enum, GDB will
1170 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1171 (gdb) print (enum E) 3
1174 * The filename part of a linespec will now match trailing components
1175 of a source file name. For example, "break gcc/expr.c:1000" will
1176 now set a breakpoint in build/gcc/expr.c, but not
1177 build/libcpp/expr.c.
1179 * The "info proc" and "generate-core-file" commands will now also
1180 work on remote targets connected to GDBserver on Linux.
1182 * The command "info catch" has been removed. It has been disabled
1183 since December 2007.
1185 * The "catch exception" and "catch assert" commands now accept
1186 a condition at the end of the command, much like the "break"
1187 command does. For instance:
1189 (gdb) catch exception Constraint_Error if Barrier = True
1191 Previously, it was possible to add a condition to such catchpoints,
1192 but it had to be done as a second step, after the catchpoint had been
1193 created, using the "condition" command.
1195 * The "info static-tracepoint-marker" command will now also work on
1196 native Linux targets with in-process agent.
1198 * GDB can now set breakpoints on inlined functions.
1200 * The .gdb_index section has been updated to include symbols for
1201 inlined functions. GDB will ignore older .gdb_index sections by
1202 default, which could cause symbol files to be loaded more slowly
1203 until their .gdb_index sections can be recreated. The new command
1204 "set use-deprecated-index-sections on" will cause GDB to use any older
1205 .gdb_index sections it finds. This will restore performance, but the
1206 ability to set breakpoints on inlined functions will be lost in symbol
1207 files with older .gdb_index sections.
1209 The .gdb_index section has also been updated to record more information
1210 about each symbol. This speeds up the "info variables", "info functions"
1211 and "info types" commands when used with programs having the .gdb_index
1212 section, as well as speeding up debugging with shared libraries using
1213 the .gdb_index section.
1215 * Ada support for GDB/MI Variable Objects has been added.
1217 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1222 ** New command -info-os is the MI equivalent of "info os".
1224 ** Output logs ("set logging" and related) now include MI output.
1228 ** "set use-deprecated-index-sections on|off"
1229 "show use-deprecated-index-sections on|off"
1230 Controls the use of deprecated .gdb_index sections.
1232 ** "catch load" and "catch unload" can be used to stop when a shared
1233 library is loaded or unloaded, respectively.
1235 ** "enable count" can be used to auto-disable a breakpoint after
1238 ** "info vtbl" can be used to show the virtual method tables for
1239 C++ and Java objects.
1241 ** "explore" and its sub commands "explore value" and "explore type"
1242 can be used to recursively explore values and types of
1243 expressions. These commands are available only if GDB is
1244 configured with '--with-python'.
1246 ** "info auto-load" shows status of all kinds of auto-loaded files,
1247 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1248 sequences of commands files, "info auto-load python-scripts"
1249 shows status of auto-loading Python script files,
1250 "info auto-load local-gdbinit" shows status of loading init file
1251 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1252 status of inferior specific thread debugging shared library loading.
1254 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1255 and "show auto-load-scripts" commands have been deprecated, use their
1256 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1257 and "show auto-load python-scripts" counterparts instead.
1259 ** "dprintf location,format,args..." creates a dynamic printf, which
1260 is basically a breakpoint that does a printf and immediately
1261 resumes your program's execution, so it is like a printf that you
1262 can insert dynamically at runtime instead of at compiletime.
1264 ** "set print symbol"
1266 Controls whether GDB attempts to display the symbol, if any,
1267 corresponding to addresses it prints. This defaults to "on", but
1268 you can set it to "off" to restore GDB's previous behavior.
1270 * Deprecated commands
1272 ** For the Renesas Super-H architecture, the "regs" command has been
1273 deprecated, and "info all-registers" should be used instead.
1277 Renesas RL78 rl78-*-elf
1278 HP OpenVMS ia64 ia64-hp-openvms*
1280 * GDBserver supports evaluation of breakpoint conditions. When
1281 support is advertised by GDBserver, GDB may be told to send the
1282 breakpoint conditions in bytecode form to GDBserver. GDBserver
1283 will only report the breakpoint trigger to GDB when its condition
1288 set mips compression
1289 show mips compression
1290 Select the compressed ISA encoding used in functions that have no symbol
1291 information available. The encoding can be set to either of:
1294 and is updated automatically from ELF file flags if available.
1296 set breakpoint condition-evaluation
1297 show breakpoint condition-evaluation
1298 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1299 GDBserver ("target"). Default option "auto" chooses the most efficient
1301 This option can improve debugger efficiency depending on the speed of the
1305 Disable auto-loading globally.
1308 Show auto-loading setting of all kinds of auto-loaded files.
1310 set auto-load gdb-scripts on|off
1311 show auto-load gdb-scripts
1312 Control auto-loading of GDB canned sequences of commands files.
1314 set auto-load python-scripts on|off
1315 show auto-load python-scripts
1316 Control auto-loading of Python script files.
1318 set auto-load local-gdbinit on|off
1319 show auto-load local-gdbinit
1320 Control loading of init file (.gdbinit) from current directory.
1322 set auto-load libthread-db on|off
1323 show auto-load libthread-db
1324 Control auto-loading of inferior specific thread debugging shared library.
1326 set auto-load scripts-directory <dir1>[:<dir2>...]
1327 show auto-load scripts-directory
1328 Set a list of directories from which to load auto-loaded scripts.
1329 Automatically loaded Python scripts and GDB scripts are located in one
1330 of the directories listed by this option.
1331 The delimiter (':' above) may differ according to the host platform.
1333 set auto-load safe-path <dir1>[:<dir2>...]
1334 show auto-load safe-path
1335 Set a list of directories from which it is safe to auto-load files.
1336 The delimiter (':' above) may differ according to the host platform.
1338 set debug auto-load on|off
1339 show debug auto-load
1340 Control display of debugging info for auto-loading the files above.
1342 set dprintf-style gdb|call|agent
1344 Control the way in which a dynamic printf is performed; "gdb"
1345 requests a GDB printf command, while "call" causes dprintf to call a
1346 function in the inferior. "agent" requests that the target agent
1347 (such as GDBserver) do the printing.
1349 set dprintf-function <expr>
1350 show dprintf-function
1351 set dprintf-channel <expr>
1352 show dprintf-channel
1353 Set the function and optional first argument to the call when using
1354 the "call" style of dynamic printf.
1356 set disconnected-dprintf on|off
1357 show disconnected-dprintf
1358 Control whether agent-style dynamic printfs continue to be in effect
1359 after GDB disconnects.
1361 * New configure options
1363 --with-auto-load-dir
1364 Configure default value for the 'set auto-load scripts-directory'
1365 setting above. It defaults to '$debugdir:$datadir/auto-load',
1366 $debugdir representing global debugging info directories (available
1367 via 'show debug-file-directory') and $datadir representing GDB's data
1368 directory (available via 'show data-directory').
1370 --with-auto-load-safe-path
1371 Configure default value for the 'set auto-load safe-path' setting
1372 above. It defaults to the --with-auto-load-dir setting.
1374 --without-auto-load-safe-path
1375 Set 'set auto-load safe-path' to '/', effectively disabling this
1378 * New remote packets
1380 z0/z1 conditional breakpoints extension
1382 The z0/z1 breakpoint insertion packets have been extended to carry
1383 a list of conditional expressions over to the remote stub depending on the
1384 condition evaluation mode. The use of this extension can be controlled
1385 via the "set remote conditional-breakpoints-packet" command.
1389 Specify the signals which the remote stub may pass to the debugged
1390 program without GDB involvement.
1392 * New command line options
1394 --init-command=FILE, -ix Like --command, -x but execute it
1395 before loading inferior.
1396 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1397 execute it before loading inferior.
1399 *** Changes in GDB 7.4
1401 * GDB now handles ambiguous linespecs more consistently; the existing
1402 FILE:LINE support has been expanded to other types of linespecs. A
1403 breakpoint will now be set on all matching locations in all
1404 inferiors, and locations will be added or removed according to
1407 * GDB now allows you to skip uninteresting functions and files when
1408 stepping with the "skip function" and "skip file" commands.
1410 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1411 and "show remote hardware-watchpoint-length-limit". These allows to
1412 set or show the maximum length limit (in bytes) of a remote
1413 target hardware watchpoint.
1415 This allows e.g. to use "unlimited" hardware watchpoints with the
1416 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1417 watchpoints are slower than real hardware watchpoints but are
1418 significantly faster than gdb software watchpoints.
1422 ** The register_pretty_printer function in module gdb.printing now takes
1423 an optional `replace' argument. If True, the new printer replaces any
1426 ** The "maint set python print-stack on|off" command has been
1427 deprecated and will be deleted in GDB 7.5.
1428 A new command: "set python print-stack none|full|message" has
1429 replaced it. Additionally, the default for "print-stack" is
1430 now "message", which just prints the error message without
1433 ** A prompt substitution hook (prompt_hook) is now available to the
1436 ** A new Python module, gdb.prompt has been added to the GDB Python
1437 modules library. This module provides functionality for
1438 escape sequences in prompts (used by set/show
1439 extended-prompt). These escape sequences are replaced by their
1440 corresponding value.
1442 ** Python commands and convenience-functions located in
1443 'data-directory'/python/gdb/command and
1444 'data-directory'/python/gdb/function are now automatically loaded
1447 ** Blocks now provide four new attributes. global_block and
1448 static_block will return the global and static blocks
1449 respectively. is_static and is_global are boolean attributes
1450 that indicate if the block is one of those two types.
1452 ** Symbols now provide the "type" attribute, the type of the symbol.
1454 ** The "gdb.breakpoint" function has been deprecated in favor of
1457 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1458 of a function. This class is based on the "finish" command
1459 available in the CLI.
1461 ** Type objects for struct and union types now allow access to
1462 the fields using standard Python dictionary (mapping) methods.
1463 For example, "some_type['myfield']" now works, as does
1464 "some_type.items()".
1466 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1469 ** A new function, "deep_items" has been added to the gdb.types
1470 module in the GDB Python modules library. This function returns
1471 an iterator over the fields of a struct or union type. Unlike
1472 the standard Python "iteritems" method, it will recursively traverse
1473 any anonymous fields.
1477 ** "*stopped" events can report several new "reason"s, such as
1480 ** Breakpoint changes are now notified using new async records, like
1481 "=breakpoint-modified".
1483 ** New command -ada-task-info.
1485 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1486 $sdir specifies the default system locations of shared libraries.
1487 $pdir specifies the directory where the libpthread used by the application
1490 GDB no longer looks in $sdir and $pdir after it has searched the directories
1491 mentioned in libthread-db-search-path. If you want to search those
1492 directories, they must be specified in libthread-db-search-path.
1493 The default value of libthread-db-search-path on GNU/Linux and Solaris
1494 systems is now "$sdir:$pdir".
1496 $pdir is not supported by gdbserver, it is currently ignored.
1497 $sdir is supported by gdbserver.
1499 * New configure option --with-iconv-bin.
1500 When using the internationalization support like the one in the GNU C
1501 library, GDB will invoke the "iconv" program to get a list of supported
1502 character sets. If this program lives in a non-standard location, one can
1503 use this option to specify where to find it.
1505 * When natively debugging programs on PowerPC BookE processors running
1506 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1507 watchpoints, which specify a mask in addition to an address to watch.
1508 The mask specifies that some bits of an address (the bits which are
1509 reset in the mask) should be ignored when matching the address accessed
1510 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1511 section in the user manual for more details.
1513 * The new option --once causes GDBserver to stop listening for connections once
1514 the first connection is made. The listening port used by GDBserver will
1515 become available after that.
1517 * New commands "info macros" and "alias" have been added.
1519 * New function parameters suffix @entry specifies value of function parameter
1520 at the time the function got called. Entry values are available only since
1526 "!" is now an alias of the "shell" command.
1527 Note that no space is needed between "!" and SHELL COMMAND.
1531 watch EXPRESSION mask MASK_VALUE
1532 The watch command now supports the mask argument which allows creation
1533 of masked watchpoints, if the current architecture supports this feature.
1535 info auto-load-scripts [REGEXP]
1536 This command was formerly named "maintenance print section-scripts".
1537 It is now generally useful and is no longer a maintenance-only command.
1539 info macro [-all] [--] MACRO
1540 The info macro command has new options `-all' and `--'. The first for
1541 printing all definitions of a macro. The second for explicitly specifying
1542 the end of arguments and the beginning of the macro name in case the macro
1543 name starts with a hyphen.
1545 collect[/s] EXPRESSIONS
1546 The tracepoint collect command now takes an optional modifier "/s"
1547 that directs it to dereference pointer-to-character types and
1548 collect the bytes of memory up to a zero byte. The behavior is
1549 similar to what you see when you use the regular print command on a
1550 string. An optional integer following the "/s" sets a bound on the
1551 number of bytes that will be collected.
1554 The trace start command now interprets any supplied arguments as a
1555 note to be recorded with the trace run, with an effect similar to
1556 setting the variable trace-notes.
1559 The trace stop command now interprets any arguments as a note to be
1560 mentioned along with the tstatus report that the trace was stopped
1561 with a command. The effect is similar to setting the variable
1564 * Tracepoints can now be enabled and disabled at any time after a trace
1565 experiment has been started using the standard "enable" and "disable"
1566 commands. It is now possible to start a trace experiment with no enabled
1567 tracepoints; GDB will display a warning, but will allow the experiment to
1568 begin, assuming that tracepoints will be enabled as needed while the trace
1571 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1572 locations with 4-byte instructions, when they were previously
1573 limited to locations with instructions of 5 bytes or longer.
1577 set debug dwarf2-read
1578 show debug dwarf2-read
1579 Turns on or off display of debugging messages related to reading
1580 DWARF debug info. The default is off.
1582 set debug symtab-create
1583 show debug symtab-create
1584 Turns on or off display of debugging messages related to symbol table
1585 creation. The default is off.
1588 show extended-prompt
1589 Set the GDB prompt, and allow escape sequences to be inserted to
1590 display miscellaneous information (see 'help set extended-prompt'
1591 for the list of sequences). This prompt (and any information
1592 accessed through the escape sequences) is updated every time the
1593 prompt is displayed.
1595 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1596 show print entry-values
1597 Set printing of frame argument values at function entry. In some cases
1598 GDB can determine the value of function argument which was passed by the
1599 function caller, even if the value was modified inside the called function.
1601 set debug entry-values
1602 show debug entry-values
1603 Control display of debugging info for determining frame argument values at
1604 function entry and virtual tail call frames.
1606 set basenames-may-differ
1607 show basenames-may-differ
1608 Set whether a source file may have multiple base names.
1609 (A "base name" is the name of a file with the directory part removed.
1610 Example: The base name of "/home/user/hello.c" is "hello.c".)
1611 If set, GDB will canonicalize file names (e.g., expand symlinks)
1612 before comparing them. Canonicalization is an expensive operation,
1613 but it allows the same file be known by more than one base name.
1614 If not set (the default), all source files are assumed to have just
1615 one base name, and gdb will do file name comparisons more efficiently.
1621 Set a user name and notes for the current and any future trace runs.
1622 This is useful for long-running and/or disconnected traces, to
1623 inform others (or yourself) as to who is running the trace, supply
1624 contact information, or otherwise explain what is going on.
1626 set trace-stop-notes
1627 show trace-stop-notes
1628 Set a note attached to the trace run, that is displayed when the
1629 trace has been stopped by a tstop command. This is useful for
1630 instance as an explanation, if you are stopping a trace run that was
1631 started by someone else.
1633 * New remote packets
1637 Dynamically enable a tracepoint in a started trace experiment.
1641 Dynamically disable a tracepoint in a started trace experiment.
1645 Set the user and notes of the trace run.
1649 Query the current status of a tracepoint.
1653 Query the minimum length of instruction at which a fast tracepoint may
1656 * Dcache size (number of lines) and line-size are now runtime-configurable
1657 via "set dcache line" and "set dcache line-size" commands.
1661 Texas Instruments TMS320C6x tic6x-*-*
1665 Renesas RL78 rl78-*-elf
1667 *** Changes in GDB 7.3.1
1669 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1671 *** Changes in GDB 7.3
1673 * GDB has a new command: "thread find [REGEXP]".
1674 It finds the thread id whose name, target id, or thread extra info
1675 matches the given regular expression.
1677 * The "catch syscall" command now works on mips*-linux* targets.
1679 * The -data-disassemble MI command now supports modes 2 and 3 for
1680 dumping the instruction opcodes.
1682 * New command line options
1684 -data-directory DIR Specify DIR as the "data-directory".
1685 This is mostly for testing purposes.
1687 * The "maint set python auto-load on|off" command has been renamed to
1688 "set auto-load-scripts on|off".
1690 * GDB has a new command: "set directories".
1691 It is like the "dir" command except that it replaces the
1692 source path list instead of augmenting it.
1694 * GDB now understands thread names.
1696 On GNU/Linux, "info threads" will display the thread name as set by
1697 prctl or pthread_setname_np.
1699 There is also a new command, "thread name", which can be used to
1700 assign a name internally for GDB to display.
1703 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1704 has been integrated into GDB.
1708 ** The function gdb.Write now accepts an optional keyword 'stream'.
1709 This keyword, when provided, will direct the output to either
1710 stdout, stderr, or GDB's logging output.
1712 ** Parameters can now be be sub-classed in Python, and in particular
1713 you may implement the get_set_doc and get_show_doc functions.
1714 This improves how Parameter set/show documentation is processed
1715 and allows for more dynamic content.
1717 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1718 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1719 have an is_valid method.
1721 ** Breakpoints can now be sub-classed in Python, and in particular
1722 you may implement a 'stop' function that is executed each time
1723 the inferior reaches that breakpoint.
1725 ** New function gdb.lookup_global_symbol looks up a global symbol.
1727 ** GDB values in Python are now callable if the value represents a
1728 function. For example, if 'some_value' represents a function that
1729 takes two integer parameters and returns a value, you can call
1730 that function like so:
1732 result = some_value (10,20)
1734 ** Module gdb.types has been added.
1735 It contains a collection of utilities for working with gdb.Types objects:
1736 get_basic_type, has_field, make_enum_dict.
1738 ** Module gdb.printing has been added.
1739 It contains utilities for writing and registering pretty-printers.
1740 New classes: PrettyPrinter, SubPrettyPrinter,
1741 RegexpCollectionPrettyPrinter.
1742 New function: register_pretty_printer.
1744 ** New commands "info pretty-printers", "enable pretty-printer" and
1745 "disable pretty-printer" have been added.
1747 ** gdb.parameter("directories") is now available.
1749 ** New function gdb.newest_frame returns the newest frame in the
1752 ** The gdb.InferiorThread class has a new "name" attribute. This
1753 holds the thread's name.
1755 ** Python Support for Inferior events.
1756 Python scripts can add observers to be notified of events
1757 occurring in the process being debugged.
1758 The following events are currently supported:
1759 - gdb.events.cont Continue event.
1760 - gdb.events.exited Inferior exited event.
1761 - gdb.events.stop Signal received, and Breakpoint hit events.
1765 ** GDB now puts template parameters in scope when debugging in an
1766 instantiation. For example, if you have:
1768 template<int X> int func (void) { return X; }
1770 then if you step into func<5>, "print X" will show "5". This
1771 feature requires proper debuginfo support from the compiler; it
1772 was added to GCC 4.5.
1774 ** The motion commands "next", "finish", "until", and "advance" now
1775 work better when exceptions are thrown. In particular, GDB will
1776 no longer lose control of the inferior; instead, the GDB will
1777 stop the inferior at the point at which the exception is caught.
1778 This functionality requires a change in the exception handling
1779 code that was introduced in GCC 4.5.
1781 * GDB now follows GCC's rules on accessing volatile objects when
1782 reading or writing target state during expression evaluation.
1783 One notable difference to prior behavior is that "print x = 0"
1784 no longer generates a read of x; the value of the assignment is
1785 now always taken directly from the value being assigned.
1787 * GDB now has some support for using labels in the program's source in
1788 linespecs. For instance, you can use "advance label" to continue
1789 execution to a label.
1791 * GDB now has support for reading and writing a new .gdb_index
1792 section. This section holds a fast index of DWARF debugging
1793 information and can be used to greatly speed up GDB startup and
1794 operation. See the documentation for `save gdb-index' for details.
1796 * The "watch" command now accepts an optional "-location" argument.
1797 When used, this causes GDB to watch the memory referred to by the
1798 expression. Such a watchpoint is never deleted due to it going out
1801 * GDB now supports thread debugging of core dumps on GNU/Linux.
1803 GDB now activates thread debugging using the libthread_db library
1804 when debugging GNU/Linux core dumps, similarly to when debugging
1805 live processes. As a result, when debugging a core dump file, GDB
1806 is now able to display pthread_t ids of threads. For example, "info
1807 threads" shows the same output as when debugging the process when it
1808 was live. In earlier releases, you'd see something like this:
1811 * 1 LWP 6780 main () at main.c:10
1813 While now you see this:
1816 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1818 It is also now possible to inspect TLS variables when debugging core
1821 When debugging a core dump generated on a machine other than the one
1822 used to run GDB, you may need to point GDB at the correct
1823 libthread_db library with the "set libthread-db-search-path"
1824 command. See the user manual for more details on this command.
1826 * When natively debugging programs on PowerPC BookE processors running
1827 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1828 which stop execution of the inferior whenever it executes an instruction
1829 at any address within the specified range. See the "PowerPC Embedded"
1830 section in the user manual for more details.
1832 * New features in the GDB remote stub, GDBserver
1834 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1835 and i686 LynxOS (version 5.x).
1837 ** GDBserver is now supported on Blackfin Linux.
1839 * New native configurations
1841 ia64 HP-UX ia64-*-hpux*
1845 Analog Devices, Inc. Blackfin Processor bfin-*
1847 * Ada task switching is now supported on sparc-elf targets when
1848 debugging a program using the Ravenscar Profile. For more information,
1849 see the "Tasking Support when using the Ravenscar Profile" section
1850 in the GDB user manual.
1852 * Guile support was removed.
1854 * New features in the GNU simulator
1856 ** The --map-info flag lists all known core mappings.
1858 ** CFI flashes may be simulated via the "cfi" device.
1860 *** Changes in GDB 7.2
1862 * Shared library support for remote targets by default
1864 When GDB is configured for a generic, non-OS specific target, like
1865 for example, --target=arm-eabi or one of the many *-*-elf targets,
1866 GDB now queries remote stubs for loaded shared libraries using the
1867 `qXfer:libraries:read' packet. Previously, shared library support
1868 was always disabled for such configurations.
1872 ** Argument Dependent Lookup (ADL)
1874 In C++ ADL lookup directs function search to the namespaces of its
1875 arguments even if the namespace has not been imported.
1885 Here the compiler will search for `foo' in the namespace of 'b'
1886 and find A::foo. GDB now supports this. This construct is commonly
1887 used in the Standard Template Library for operators.
1889 ** Improved User Defined Operator Support
1891 In addition to member operators, GDB now supports lookup of operators
1892 defined in a namespace and imported with a `using' directive, operators
1893 defined in the global scope, operators imported implicitly from an
1894 anonymous namespace, and the ADL operators mentioned in the previous
1896 GDB now also supports proper overload resolution for all the previously
1897 mentioned flavors of operators.
1899 ** static const class members
1901 Printing of static const class members that are initialized in the
1902 class definition has been fixed.
1904 * Windows Thread Information Block access.
1906 On Windows targets, GDB now supports displaying the Windows Thread
1907 Information Block (TIB) structure. This structure is visible either
1908 by using the new command `info w32 thread-information-block' or, by
1909 dereferencing the new convenience variable named `$_tlb', a
1910 thread-specific pointer to the TIB. This feature is also supported
1911 when remote debugging using GDBserver.
1913 * Static tracepoints
1915 Static tracepoints are calls in the user program into a tracing
1916 library. One such library is a port of the LTTng kernel tracer to
1917 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1918 When debugging with GDBserver, GDB now supports combining the GDB
1919 tracepoint machinery with such libraries. For example: the user can
1920 use GDB to probe a static tracepoint marker (a call from the user
1921 program into the tracing library) with the new "strace" command (see
1922 "New commands" below). This creates a "static tracepoint" in the
1923 breakpoint list, that can be manipulated with the same feature set
1924 as fast and regular tracepoints. E.g., collect registers, local and
1925 global variables, collect trace state variables, and define
1926 tracepoint conditions. In addition, the user can collect extra
1927 static tracepoint marker specific data, by collecting the new
1928 $_sdata internal variable. When analyzing the trace buffer, you can
1929 inspect $_sdata like any other variable available to GDB. For more
1930 information, see the "Tracepoints" chapter in GDB user manual. New
1931 remote packets have been defined to support static tracepoints, see
1932 the "New remote packets" section below.
1934 * Better reconstruction of tracepoints after disconnected tracing
1936 GDB will attempt to download the original source form of tracepoint
1937 definitions when starting a trace run, and then will upload these
1938 upon reconnection to the target, resulting in a more accurate
1939 reconstruction of the tracepoints that are in use on the target.
1943 You can now exercise direct control over the ways that GDB can
1944 affect your program. For instance, you can disallow the setting of
1945 breakpoints, so that the program can run continuously (assuming
1946 non-stop mode). In addition, the "observer" variable is available
1947 to switch all of the different controls; in observer mode, GDB
1948 cannot affect the target's behavior at all, which is useful for
1949 tasks like diagnosing live systems in the field.
1951 * The new convenience variable $_thread holds the number of the
1954 * New remote packets
1958 Return the address of the Windows Thread Information Block of a given thread.
1962 In response to several of the tracepoint packets, the target may now
1963 also respond with a number of intermediate `qRelocInsn' request
1964 packets before the final result packet, to have GDB handle
1965 relocating an instruction to execute at a different address. This
1966 is particularly useful for stubs that support fast tracepoints. GDB
1967 reports support for this feature in the qSupported packet.
1971 List static tracepoint markers in the target program.
1975 List static tracepoint markers at a given address in the target
1978 qXfer:statictrace:read
1980 Read the static trace data collected (by a `collect $_sdata'
1981 tracepoint action). The remote stub reports support for this packet
1982 to gdb's qSupported query.
1986 Send the current settings of GDB's permission flags.
1990 Send part of the source (textual) form of a tracepoint definition,
1991 which includes location, conditional, and action list.
1993 * The source command now accepts a -s option to force searching for the
1994 script in the source search path even if the script name specifies
1997 * New features in the GDB remote stub, GDBserver
1999 - GDBserver now support tracepoints (including fast tracepoints, and
2000 static tracepoints). The feature is currently supported by the
2001 i386-linux and amd64-linux builds. See the "Tracepoints support
2002 in gdbserver" section in the manual for more information.
2004 GDBserver JIT compiles the tracepoint's conditional agent
2005 expression bytecode into native code whenever possible for low
2006 overhead dynamic tracepoints conditionals. For such tracepoints,
2007 an expression that examines program state is evaluated when the
2008 tracepoint is reached, in order to determine whether to capture
2009 trace data. If the condition is simple and false, processing the
2010 tracepoint finishes very quickly and no data is gathered.
2012 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2013 for static tracepoints support.
2015 - GDBserver now supports x86_64 Windows 64-bit debugging.
2017 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2018 it understands register description.
2020 * The --batch flag now disables pagination and queries.
2022 * X86 general purpose registers
2024 GDB now supports reading/writing byte, word and double-word x86
2025 general purpose registers directly. This means you can use, say,
2026 $ah or $ax to refer, respectively, to the byte register AH and
2027 16-bit word register AX that are actually portions of the 32-bit
2028 register EAX or 64-bit register RAX.
2030 * The `commands' command now accepts a range of breakpoints to modify.
2031 A plain `commands' following a command that creates multiple
2032 breakpoints affects all the breakpoints set by that command. This
2033 applies to breakpoints set by `rbreak', and also applies when a
2034 single `break' command creates multiple breakpoints (e.g.,
2035 breakpoints on overloaded c++ functions).
2037 * The `rbreak' command now accepts a filename specification as part of
2038 its argument, limiting the functions selected by the regex to those
2039 in the specified file.
2041 * Support for remote debugging Windows and SymbianOS shared libraries
2042 from Unix hosts has been improved. Non Windows GDB builds now can
2043 understand target reported file names that follow MS-DOS based file
2044 system semantics, such as file names that include drive letters and
2045 use the backslash character as directory separator. This makes it
2046 possible to transparently use the "set sysroot" and "set
2047 solib-search-path" on Unix hosts to point as host copies of the
2048 target's shared libraries. See the new command "set
2049 target-file-system-kind" described below, and the "Commands to
2050 specify files" section in the user manual for more information.
2054 eval template, expressions...
2055 Convert the values of one or more expressions under the control
2056 of the string template to a command line, and call it.
2058 set target-file-system-kind unix|dos-based|auto
2059 show target-file-system-kind
2060 Set or show the assumed file system kind for target reported file
2063 save breakpoints <filename>
2064 Save all current breakpoint definitions to a file suitable for use
2065 in a later debugging session. To read the saved breakpoint
2066 definitions, use the `source' command.
2068 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2071 info static-tracepoint-markers
2072 Display information about static tracepoint markers in the target.
2074 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2075 Define a static tracepoint by probing a marker at the given
2076 function, line, address, or marker ID.
2080 Enable and disable observer mode.
2082 set may-write-registers on|off
2083 set may-write-memory on|off
2084 set may-insert-breakpoints on|off
2085 set may-insert-tracepoints on|off
2086 set may-insert-fast-tracepoints on|off
2087 set may-interrupt on|off
2088 Set individual permissions for GDB effects on the target. Note that
2089 some of these settings can have undesirable or surprising
2090 consequences, particularly when changed in the middle of a session.
2091 For instance, disabling the writing of memory can prevent
2092 breakpoints from being inserted, cause single-stepping to fail, or
2093 even crash your program, if you disable after breakpoints have been
2094 inserted. However, GDB should not crash.
2096 set record memory-query on|off
2097 show record memory-query
2098 Control whether to stop the inferior if memory changes caused
2099 by an instruction cannot be recorded.
2104 The disassemble command now supports "start,+length" form of two arguments.
2108 ** GDB now provides a new directory location, called the python directory,
2109 where Python scripts written for GDB can be installed. The location
2110 of that directory is <data-directory>/python, where <data-directory>
2111 is the GDB data directory. For more details, see section `Scripting
2112 GDB using Python' in the manual.
2114 ** The GDB Python API now has access to breakpoints, symbols, symbol
2115 tables, program spaces, inferiors, threads and frame's code blocks.
2116 Additionally, GDB Parameters can now be created from the API, and
2117 manipulated via set/show in the CLI.
2119 ** New functions gdb.target_charset, gdb.target_wide_charset,
2120 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2122 ** New exception gdb.GdbError.
2124 ** Pretty-printers are now also looked up in the current program space.
2126 ** Pretty-printers can now be individually enabled and disabled.
2128 ** GDB now looks for names of Python scripts to auto-load in a
2129 special section named `.debug_gdb_scripts', in addition to looking
2130 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2132 * Tracepoint actions were unified with breakpoint commands. In particular,
2133 there are no longer differences in "info break" output for breakpoints and
2134 tracepoints and the "commands" command can be used for both tracepoints and
2135 regular breakpoints.
2139 ARM Symbian arm*-*-symbianelf*
2141 * D language support.
2142 GDB now supports debugging programs written in the D programming
2145 * GDB now supports the extended ptrace interface for PowerPC which is
2146 available since Linux kernel version 2.6.34. This automatically enables
2147 any hardware breakpoints and additional hardware watchpoints available in
2148 the processor. The old ptrace interface exposes just one hardware
2149 watchpoint and no hardware breakpoints.
2151 * GDB is now able to use the Data Value Compare (DVC) register available on
2152 embedded PowerPC processors to implement in hardware simple watchpoint
2153 conditions of the form:
2155 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2157 This works in native GDB running on Linux kernels with the extended ptrace
2158 interface mentioned above.
2160 *** Changes in GDB 7.1
2164 ** Namespace Support
2166 GDB now supports importing of namespaces in C++. This enables the
2167 user to inspect variables from imported namespaces. Support for
2168 namepace aliasing has also been added. So, if a namespace is
2169 aliased in the current scope (e.g. namepace C=A; ) the user can
2170 print variables using the alias (e.g. (gdb) print C::x).
2174 All known bugs relating to the printing of virtual base class were
2175 fixed. It is now possible to call overloaded static methods using a
2180 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2181 and reinterpret_cast<> are now handled by the C++ expression parser.
2185 Xilinx MicroBlaze microblaze-*-*
2190 Xilinx MicroBlaze microblaze
2193 * Multi-program debugging.
2195 GDB now has support for multi-program (a.k.a. multi-executable or
2196 multi-exec) debugging. This allows for debugging multiple inferiors
2197 simultaneously each running a different program under the same GDB
2198 session. See "Debugging Multiple Inferiors and Programs" in the
2199 manual for more information. This implied some user visible changes
2200 in the multi-inferior support. For example, "info inferiors" now
2201 lists inferiors that are not running yet or that have exited
2202 already. See also "New commands" and "New options" below.
2204 * New tracing features
2206 GDB's tracepoint facility now includes several new features:
2208 ** Trace state variables
2210 GDB tracepoints now include support for trace state variables, which
2211 are variables managed by the target agent during a tracing
2212 experiment. They are useful for tracepoints that trigger each
2213 other, so for instance one tracepoint can count hits in a variable,
2214 and then a second tracepoint has a condition that is true when the
2215 count reaches a particular value. Trace state variables share the
2216 $-syntax of GDB convenience variables, and can appear in both
2217 tracepoint actions and condition expressions. Use the "tvariable"
2218 command to create, and "info tvariables" to view; see "Trace State
2219 Variables" in the manual for more detail.
2223 GDB now includes an option for defining fast tracepoints, which
2224 targets may implement more efficiently, such as by installing a jump
2225 into the target agent rather than a trap instruction. The resulting
2226 speedup can be by two orders of magnitude or more, although the
2227 tradeoff is that some program locations on some target architectures
2228 might not allow fast tracepoint installation, for instance if the
2229 instruction to be replaced is shorter than the jump. To request a
2230 fast tracepoint, use the "ftrace" command, with syntax identical to
2231 the regular trace command.
2233 ** Disconnected tracing
2235 It is now possible to detach GDB from the target while it is running
2236 a trace experiment, then reconnect later to see how the experiment
2237 is going. In addition, a new variable disconnected-tracing lets you
2238 tell the target agent whether to continue running a trace if the
2239 connection is lost unexpectedly.
2243 GDB now has the ability to save the trace buffer into a file, and
2244 then use that file as a target, similarly to you can do with
2245 corefiles. You can select trace frames, print data that was
2246 collected in them, and use tstatus to display the state of the
2247 tracing run at the moment that it was saved. To create a trace
2248 file, use "tsave <filename>", and to use it, do "target tfile
2251 ** Circular trace buffer
2253 You can ask the target agent to handle the trace buffer as a
2254 circular buffer, discarding the oldest trace frames to make room for
2255 newer ones, by setting circular-trace-buffer to on. This feature may
2256 not be available for all target agents.
2261 The disassemble command, when invoked with two arguments, now requires
2262 the arguments to be comma-separated.
2265 The info variables command now displays variable definitions. Files
2266 which only declare a variable are not shown.
2269 The source command is now capable of sourcing Python scripts.
2270 This feature is dependent on the debugger being build with Python
2273 Related to this enhancement is also the introduction of a new command
2274 "set script-extension" (see below).
2276 * New commands (for set/show, see "New options" below)
2278 record save [<FILENAME>]
2279 Save a file (in core file format) containing the process record
2280 execution log for replay debugging at a later time.
2282 record restore <FILENAME>
2283 Restore the process record execution log that was saved at an
2284 earlier time, for replay debugging.
2286 add-inferior [-copies <N>] [-exec <FILENAME>]
2289 clone-inferior [-copies <N>] [ID]
2290 Make a new inferior ready to execute the same program another
2291 inferior has loaded.
2296 maint info program-spaces
2297 List the program spaces loaded into GDB.
2299 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2300 show remote interrupt-sequence
2301 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2302 as the sequence to the remote target in order to interrupt the execution.
2303 Ctrl-C is a default. Some system prefers BREAK which is high level of
2304 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2305 Magic SysRq g. It is BREAK signal and character 'g'.
2307 set remote interrupt-on-connect [on | off]
2308 show remote interrupt-on-connect
2309 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2310 remote target when gdb connects to it. This is needed when you debug
2313 set remotebreak [on | off]
2315 Deprecated. Use "set/show remote interrupt-sequence" instead.
2317 tvariable $NAME [ = EXP ]
2318 Create or modify a trace state variable.
2321 List trace state variables and their values.
2323 delete tvariable $NAME ...
2324 Delete one or more trace state variables.
2327 Evaluate the given expressions without collecting anything into the
2328 trace buffer. (Valid in tracepoint actions only.)
2330 ftrace FN / FILE:LINE / *ADDR
2331 Define a fast tracepoint at the given function, line, or address.
2333 * New expression syntax
2335 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2336 GDB now parses 0b101010 identically with 42.
2340 set follow-exec-mode new|same
2341 show follow-exec-mode
2342 Control whether GDB reuses the same inferior across an exec call or
2343 creates a new one. This is useful to be able to restart the old
2344 executable after the inferior having done an exec call.
2346 set default-collect EXPR, ...
2347 show default-collect
2348 Define a list of expressions to be collected at each tracepoint.
2349 This is a useful way to ensure essential items are not overlooked,
2350 such as registers or a critical global variable.
2352 set disconnected-tracing
2353 show disconnected-tracing
2354 If set to 1, the target is instructed to continue tracing if it
2355 loses its connection to GDB. If 0, the target is to stop tracing
2358 set circular-trace-buffer
2359 show circular-trace-buffer
2360 If set to on, the target is instructed to use a circular trace buffer
2361 and discard the oldest trace frames instead of stopping the trace due
2362 to a full trace buffer. If set to off, the trace stops when the buffer
2363 fills up. Some targets may not support this.
2365 set script-extension off|soft|strict
2366 show script-extension
2367 If set to "off", the debugger does not perform any script language
2368 recognition, and all sourced files are assumed to be GDB scripts.
2369 If set to "soft" (the default), files are sourced according to
2370 filename extension, falling back to GDB scripts if the first
2372 If set to "strict", files are sourced according to filename extension.
2374 set ada trust-PAD-over-XVS on|off
2375 show ada trust-PAD-over-XVS
2376 If off, activate a workaround against a bug in the debugging information
2377 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2378 the GCC sources for more information about the GNAT encoding and
2379 PAD types in particular). It is always safe to set this option to
2380 off, but this introduces a slight performance penalty. The default
2383 * Python API Improvements
2385 ** GDB provides the new class gdb.LazyString. This is useful in
2386 some pretty-printing cases. The new method gdb.Value.lazy_string
2387 provides a simple way to create objects of this type.
2389 ** The fields returned by gdb.Type.fields now have an
2390 `is_base_class' attribute.
2392 ** The new method gdb.Type.range returns the range of an array type.
2394 ** The new method gdb.parse_and_eval can be used to parse and
2395 evaluate an expression.
2397 * New remote packets
2400 Define a trace state variable.
2403 Get the current value of a trace state variable.
2406 Set desired tracing behavior upon disconnection.
2409 Set the trace buffer to be linear or circular.
2412 Get data about the tracepoints currently in use.
2416 Process record now works correctly with hardware watchpoints.
2418 Multiple bug fixes have been made to the mips-irix port, making it
2419 much more reliable. In particular:
2420 - Debugging threaded applications is now possible again. Previously,
2421 GDB would hang while starting the program, or while waiting for
2422 the program to stop at a breakpoint.
2423 - Attaching to a running process no longer hangs.
2424 - An error occurring while loading a core file has been fixed.
2425 - Changing the value of the PC register now works again. This fixes
2426 problems observed when using the "jump" command, or when calling
2427 a function from GDB, or even when assigning a new value to $pc.
2428 - With the "finish" and "return" commands, the return value for functions
2429 returning a small array is now correctly printed.
2430 - It is now possible to break on shared library code which gets executed
2431 during a shared library init phase (code executed while executing
2432 their .init section). Previously, the breakpoint would have no effect.
2433 - GDB is now able to backtrace through the signal handler for
2434 non-threaded programs.
2436 PIE (Position Independent Executable) programs debugging is now supported.
2437 This includes debugging execution of PIC (Position Independent Code) shared
2438 libraries although for that, it should be possible to run such libraries as an
2441 *** Changes in GDB 7.0
2443 * GDB now has an interface for JIT compilation. Applications that
2444 dynamically generate code can create symbol files in memory and register
2445 them with GDB. For users, the feature should work transparently, and
2446 for JIT developers, the interface is documented in the GDB manual in the
2447 "JIT Compilation Interface" chapter.
2449 * Tracepoints may now be conditional. The syntax is as for
2450 breakpoints; either an "if" clause appended to the "trace" command,
2451 or the "condition" command is available. GDB sends the condition to
2452 the target for evaluation using the same bytecode format as is used
2453 for tracepoint actions.
2455 * The disassemble command now supports: an optional /r modifier, print the
2456 raw instructions in hex as well as in symbolic form, and an optional /m
2457 modifier to print mixed source+assembly.
2459 * Process record and replay
2461 In a architecture environment that supports ``process record and
2462 replay'', ``process record and replay'' target can record a log of
2463 the process execution, and replay it with both forward and reverse
2466 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2467 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2468 set execution-direction {forward|reverse}, for targets that support
2471 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2472 feature is available with a native GDB running on kernel version
2475 * GDB now has support for multi-byte and wide character sets on the
2476 target. Strings whose character type is wchar_t, char16_t, or
2477 char32_t are now correctly printed. GDB supports wide- and unicode-
2478 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2479 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2480 `printf'. This feature requires iconv to work properly; if your
2481 system does not have a working iconv, GDB can use GNU libiconv. See
2482 the installation instructions for more information.
2484 * GDB now supports automatic retrieval of shared library files from
2485 remote targets. To use this feature, specify a system root that begins
2486 with the `remote:' prefix, either via the `set sysroot' command or via
2487 the `--with-sysroot' configure-time option.
2489 * "info sharedlibrary" now takes an optional regex of libraries to show,
2490 and it now reports if a shared library has no debugging information.
2492 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2493 now complete on file names.
2495 * When completing in expressions, gdb will attempt to limit
2496 completions to allowable structure or union fields, where appropriate.
2497 For instance, consider:
2499 # struct example { int f1; double f2; };
2500 # struct example variable;
2503 If the user types TAB at the end of this command line, the available
2504 completions will be "f1" and "f2".
2506 * Inlined functions are now supported. They show up in backtraces, and
2507 the "step", "next", and "finish" commands handle them automatically.
2509 * GDB now supports the token-splicing (##) and stringification (#)
2510 operators when expanding macros. It also supports variable-arity
2513 * GDB now supports inspecting extra signal information, exported by
2514 the new $_siginfo convenience variable. The feature is currently
2515 implemented on linux ARM, i386 and amd64.
2517 * GDB can now display the VFP floating point registers and NEON vector
2518 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2519 can provide these registers (requires Linux 2.6.30 or later). Remote
2520 and simulator targets may also provide them.
2522 * New remote packets
2525 Search memory for a sequence of bytes.
2528 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2529 operation over reliable transport links. Use of this packet is
2530 controlled by the `set remote noack-packet' command.
2533 Kill the process with the specified process ID. Use this in preference
2534 to `k' when multiprocess protocol extensions are supported.
2537 Obtains additional operating system information
2541 Read or write additional signal information.
2543 * Removed remote protocol undocumented extension
2545 An undocumented extension to the remote protocol's `S' stop reply
2546 packet that permited the stub to pass a process id was removed.
2547 Remote servers should use the `T' stop reply packet instead.
2549 * GDB now supports multiple function calling conventions according to the
2550 DWARF-2 DW_AT_calling_convention function attribute.
2552 * The SH target utilizes the aforementioned change to distinguish between gcc
2553 and Renesas calling convention. It also adds the new CLI commands
2554 `set/show sh calling-convention'.
2556 * GDB can now read compressed debug sections, as produced by GNU gold
2557 with the --compress-debug-sections=zlib flag.
2559 * 64-bit core files are now supported on AIX.
2561 * Thread switching is now supported on Tru64.
2563 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2564 which will be allocated using malloc later in program execution.
2566 * The qXfer:libraries:read remote procotol packet now allows passing a
2567 list of section offsets.
2569 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2570 conditions handling signals delivered during attach or thread creation
2571 have also been fixed.
2573 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2574 From the user's standpoint, all unqualified instances of True and False
2575 are treated as the standard definitions, regardless of context.
2577 * GDB now parses C++ symbol and type names more flexibly. For
2580 template<typename T> class C { };
2583 GDB will now correctly handle all of:
2585 ptype C<char const *>
2586 ptype C<char const*>
2587 ptype C<const char *>
2588 ptype C<const char*>
2590 * New features in the GDB remote stub, gdbserver
2592 - The "--wrapper" command-line argument tells gdbserver to use a
2593 wrapper program to launch programs for debugging.
2595 - On PowerPC and S/390 targets, it is now possible to use a single
2596 gdbserver executable to debug both 32-bit and 64-bit programs.
2597 (This requires gdbserver itself to be built as a 64-bit executable.)
2599 - gdbserver uses the new noack protocol mode for TCP connections to
2600 reduce communications latency, if also supported and enabled in GDB.
2602 - Support for the sparc64-linux-gnu target is now included in
2605 - The amd64-linux build of gdbserver now supports debugging both
2606 32-bit and 64-bit programs.
2608 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2609 now support hardware watchpoints, and will use them automatically
2614 GDB now has support for scripting using Python. Whether this is
2615 available is determined at configure time.
2617 New GDB commands can now be written in Python.
2619 * Ada tasking support
2621 Ada tasks can now be inspected in GDB. The following commands have
2625 Print the list of Ada tasks.
2627 Print detailed information about task number N.
2629 Print the task number of the current task.
2631 Switch the context of debugging to task number N.
2633 * Support for user-defined prefixed commands. The "define" command can
2634 add new commands to existing prefixes, e.g. "target".
2636 * Multi-inferior, multi-process debugging.
2638 GDB now has generalized support for multi-inferior debugging. See
2639 "Debugging Multiple Inferiors" in the manual for more information.
2640 Although availability still depends on target support, the command
2641 set is more uniform now. The GNU/Linux specific multi-forks support
2642 has been migrated to this new framework. This implied some user
2643 visible changes; see "New commands" and also "Removed commands"
2646 * Target descriptions can now describe the target OS ABI. See the
2647 "Target Description Format" section in the user manual for more
2650 * Target descriptions can now describe "compatible" architectures
2651 to indicate that the target can execute applications for a different
2652 architecture in addition to those for the main target architecture.
2653 See the "Target Description Format" section in the user manual for
2656 * Multi-architecture debugging.
2658 GDB now includes general supports for debugging applications on
2659 hybrid systems that use more than one single processor architecture
2660 at the same time. Each such hybrid architecture still requires
2661 specific support to be added. The only hybrid architecture supported
2662 in this version of GDB is the Cell Broadband Engine.
2664 * GDB now supports integrated debugging of Cell/B.E. applications that
2665 use both the PPU and SPU architectures. To enable support for hybrid
2666 Cell/B.E. debugging, you need to configure GDB to support both the
2667 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2668 --enable-targets configure option.
2670 * Non-stop mode debugging.
2672 For some targets, GDB now supports an optional mode of operation in
2673 which you can examine stopped threads while other threads continue
2674 to execute freely. This is referred to as non-stop mode, with the
2675 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2676 section in the user manual for more information.
2678 To be able to support remote non-stop debugging, a remote stub needs
2679 to implement the non-stop mode remote protocol extensions, as
2680 described in the "Remote Non-Stop" section of the user manual. The
2681 GDB remote stub, gdbserver, has been adjusted to support these
2682 extensions on linux targets.
2684 * New commands (for set/show, see "New options" below)
2686 catch syscall [NAME(S) | NUMBER(S)]
2687 Catch system calls. Arguments, which should be names of system
2688 calls or their numbers, mean catch only those syscalls. Without
2689 arguments, every syscall will be caught. When the inferior issues
2690 any of the specified syscalls, GDB will stop and announce the system
2691 call, both when it is called and when its call returns. This
2692 feature is currently available with a native GDB running on the
2693 Linux Kernel, under the following architectures: x86, x86_64,
2694 PowerPC and PowerPC64.
2696 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2698 Search memory for a sequence of bytes.
2700 maint set python print-stack
2701 maint show python print-stack
2702 Show a stack trace when an error is encountered in a Python script.
2705 Invoke CODE by passing it to the Python interpreter.
2710 These allow macros to be defined, undefined, and listed
2714 Show operating system information about processes.
2717 List the inferiors currently under GDB's control.
2720 Switch focus to inferior number NUM.
2723 Detach from inferior number NUM.
2726 Kill inferior number NUM.
2730 set spu stop-on-load
2731 show spu stop-on-load
2732 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2734 set spu auto-flush-cache
2735 show spu auto-flush-cache
2736 Control whether to automatically flush the software-managed cache
2737 during Cell/B.E. debugging.
2739 set sh calling-convention
2740 show sh calling-convention
2741 Control the calling convention used when calling SH target functions.
2744 show debug timestamp
2745 Control display of timestamps with GDB debugging output.
2747 set disassemble-next-line
2748 show disassemble-next-line
2749 Control display of disassembled source lines or instructions when
2752 set remote noack-packet
2753 show remote noack-packet
2754 Set/show the use of remote protocol QStartNoAckMode packet. See above
2755 under "New remote packets."
2757 set remote query-attached-packet
2758 show remote query-attached-packet
2759 Control use of remote protocol `qAttached' (query-attached) packet.
2761 set remote read-siginfo-object
2762 show remote read-siginfo-object
2763 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2766 set remote write-siginfo-object
2767 show remote write-siginfo-object
2768 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2771 set remote reverse-continue
2772 show remote reverse-continue
2773 Control use of remote protocol 'bc' (reverse-continue) packet.
2775 set remote reverse-step
2776 show remote reverse-step
2777 Control use of remote protocol 'bs' (reverse-step) packet.
2779 set displaced-stepping
2780 show displaced-stepping
2781 Control displaced stepping mode. Displaced stepping is a way to
2782 single-step over breakpoints without removing them from the debuggee.
2783 Also known as "out-of-line single-stepping".
2786 show debug displaced
2787 Control display of debugging info for displaced stepping.
2789 maint set internal-error
2790 maint show internal-error
2791 Control what GDB does when an internal error is detected.
2793 maint set internal-warning
2794 maint show internal-warning
2795 Control what GDB does when an internal warning is detected.
2800 Use a wrapper program to launch programs for debugging.
2802 set multiple-symbols (all|ask|cancel)
2803 show multiple-symbols
2804 The value of this variable can be changed to adjust the debugger behavior
2805 when an expression or a breakpoint location contains an ambiguous symbol
2806 name (an overloaded function name, for instance).
2808 set breakpoint always-inserted
2809 show breakpoint always-inserted
2810 Keep breakpoints always inserted in the target, as opposed to inserting
2811 them when resuming the target, and removing them when the target stops.
2812 This option can improve debugger performance on slow remote targets.
2814 set arm fallback-mode (arm|thumb|auto)
2815 show arm fallback-mode
2816 set arm force-mode (arm|thumb|auto)
2818 These commands control how ARM GDB determines whether instructions
2819 are ARM or Thumb. The default for both settings is auto, which uses
2820 the current CPSR value for instructions without symbols; previous
2821 versions of GDB behaved as if "set arm fallback-mode arm".
2823 set disable-randomization
2824 show disable-randomization
2825 Standalone programs run with the virtual address space randomization enabled
2826 by default on some platforms. This option keeps the addresses stable across
2827 multiple debugging sessions.
2831 Control whether other threads are stopped or not when some thread hits
2836 Requests that asynchronous execution is enabled in the target, if available.
2837 In this case, it's possible to resume target in the background, and interact
2838 with GDB while the target is running. "show target-async" displays the
2839 current state of asynchronous execution of the target.
2841 set target-wide-charset
2842 show target-wide-charset
2843 The target-wide-charset is the name of the character set that GDB
2844 uses when printing characters whose type is wchar_t.
2846 set tcp auto-retry (on|off)
2848 set tcp connect-timeout
2849 show tcp connect-timeout
2850 These commands allow GDB to retry failed TCP connections to a remote stub
2851 with a specified timeout period; this is useful if the stub is launched
2852 in parallel with GDB but may not be ready to accept connections immediately.
2854 set libthread-db-search-path
2855 show libthread-db-search-path
2856 Control list of directories which GDB will search for appropriate
2859 set schedule-multiple (on|off)
2860 show schedule-multiple
2861 Allow GDB to resume all threads of all processes or only threads of
2862 the current process.
2866 Use more aggressive caching for accesses to the stack. This improves
2867 performance of remote debugging (particularly backtraces) without
2868 affecting correctness.
2870 set interactive-mode (on|off|auto)
2871 show interactive-mode
2872 Control whether GDB runs in interactive mode (on) or not (off).
2873 When in interactive mode, GDB waits for the user to answer all
2874 queries. Otherwise, GDB does not wait and assumes the default
2875 answer. When set to auto (the default), GDB determines which
2876 mode to use based on the stdin settings.
2881 For program forks, this is replaced by the new more generic `info
2882 inferiors' command. To list checkpoints, you can still use the
2883 `info checkpoints' command, which was an alias for the `info forks'
2887 Replaced by the new `inferior' command. To switch between
2888 checkpoints, you can still use the `restart' command, which was an
2889 alias for the `fork' command.
2892 This is removed, since some targets don't have a notion of
2893 processes. To switch between processes, you can still use the
2894 `inferior' command using GDB's own inferior number.
2897 For program forks, this is replaced by the new more generic `kill
2898 inferior' command. To delete a checkpoint, you can still use the
2899 `delete checkpoint' command, which was an alias for the `delete
2903 For program forks, this is replaced by the new more generic `detach
2904 inferior' command. To detach a checkpoint, you can still use the
2905 `detach checkpoint' command, which was an alias for the `detach
2908 * New native configurations
2910 x86/x86_64 Darwin i[34567]86-*-darwin*
2912 x86_64 MinGW x86_64-*-mingw*
2916 Lattice Mico32 lm32-*
2917 x86 DICOS i[34567]86-*-dicos*
2918 x86_64 DICOS x86_64-*-dicos*
2921 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2922 (mingw32ce) debugging.
2928 These commands were actually not implemented on any target.
2930 *** Changes in GDB 6.8
2932 * New native configurations
2934 NetBSD/hppa hppa*-*netbsd*
2935 Xtensa GNU/Linux xtensa*-*-linux*
2939 NetBSD/hppa hppa*-*-netbsd*
2940 Xtensa GNU/Lunux xtensa*-*-linux*
2942 * Change in command line behavior -- corefiles vs. process ids.
2944 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2945 attaching to process NUMBER fails, GDB no longer attempts to open a
2946 core file named NUMBER. Attaching to a program using the -c option
2947 is no longer supported. Instead, use the '-p' or '--pid' options.
2949 * GDB can now be built as a native debugger for debugging Windows x86
2950 (mingw32) Portable Executable (PE) programs.
2952 * Pending breakpoints no longer change their number when their address
2955 * GDB now supports breakpoints with multiple locations,
2956 including breakpoints on C++ constructors, inside C++ templates,
2957 and in inlined functions.
2959 * GDB's ability to debug optimized code has been improved. GDB more
2960 accurately identifies function bodies and lexical blocks that occupy
2961 more than one contiguous range of addresses.
2963 * Target descriptions can now describe registers for PowerPC.
2965 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2966 registers on PowerPC targets.
2968 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2969 targets even when the libthread_db library is not available.
2971 * The GDB remote stub, gdbserver, now supports the new file transfer
2972 commands (remote put, remote get, and remote delete).
2974 * The GDB remote stub, gdbserver, now supports run and attach in
2975 extended-remote mode.
2977 * hppa*64*-*-hpux11* target broken
2978 The debugger is unable to start a program and fails with the following
2979 error: "Error trying to get information about dynamic linker".
2980 The gdb-6.7 release is also affected.
2982 * GDB now supports the --enable-targets= configure option to allow
2983 building a single GDB executable that supports multiple remote
2984 target architectures.
2986 * GDB now supports debugging C and C++ programs which use the
2987 Decimal Floating Point extension. In addition, the PowerPC target
2988 now has a set of pseudo-registers to inspect decimal float values
2989 stored in two consecutive float registers.
2991 * The -break-insert MI command can optionally create pending
2994 * Improved support for debugging Ada
2995 Many improvements to the Ada language support have been made. These
2997 - Better support for Ada2005 interface types
2998 - Improved handling of arrays and slices in general
2999 - Better support for Taft-amendment types
3000 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3002 - Improved command completion in Ada
3005 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3010 set print frame-arguments (all|scalars|none)
3011 show print frame-arguments
3012 The value of this variable can be changed to control which argument
3013 values should be printed by the debugger when displaying a frame.
3018 Transfer files to and from a remote target, and delete remote files.
3025 Transfer files to and from a remote target, and delete remote files.
3027 * New remote packets
3034 Open, close, read, write, and delete files on the remote system.
3037 Attach to an existing process on the remote system, in extended-remote
3041 Run a new process on the remote system, in extended-remote mode.
3043 *** Changes in GDB 6.7
3045 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3046 bfd, libiberty and opcodes, as revealed by static analysis donated by
3047 Coverity, Inc. (http://scan.coverity.com).
3049 * When looking up multiply-defined global symbols, GDB will now prefer the
3050 symbol definition in the current shared library if it was built using the
3051 -Bsymbolic linker option.
3053 * When the Text User Interface (TUI) is not configured, GDB will now
3054 recognize the -tui command-line option and print a message that the TUI
3057 * The GDB remote stub, gdbserver, now has lower overhead for high
3058 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3060 * GDB for MIPS targets now autodetects whether a remote target provides
3061 32-bit or 64-bit register values.
3063 * Support for C++ member pointers has been improved.
3065 * GDB now understands XML target descriptions, which specify the
3066 target's overall architecture. GDB can read a description from
3067 a local file or over the remote serial protocol.
3069 * Vectors of single-byte data use a new integer type which is not
3070 automatically displayed as character or string data.
3072 * The /s format now works with the print command. It displays
3073 arrays of single-byte integers and pointers to single-byte integers
3076 * Target descriptions can now describe target-specific registers,
3077 for architectures which have implemented the support (currently
3078 only ARM, M68K, and MIPS).
3080 * GDB and the GDB remote stub, gdbserver, now support the XScale
3083 * The GDB remote stub, gdbserver, has been updated to support
3084 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3085 has been rewritten to use the standard GDB remote protocol.
3087 * GDB can now step into C++ functions which are called through thunks.
3089 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3091 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3092 layout. It also supports a TextSeg= and DataSeg= response when only
3093 segment base addresses (rather than offsets) are available.
3095 * The /i format now outputs any trailing branch delay slot instructions
3096 immediately following the last instruction within the count specified.
3098 * The GDB remote protocol "T" stop reply packet now supports a
3099 "library" response. Combined with the new "qXfer:libraries:read"
3100 packet, this response allows GDB to debug shared libraries on targets
3101 where the operating system manages the list of loaded libraries (e.g.
3102 Windows and SymbianOS).
3104 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3105 (DLLs) on Windows and Windows CE targets.
3107 * GDB now supports a faster verification that a .debug file matches its binary
3108 according to its build-id signature, if the signature is present.
3114 Enable or disable hardware flow control (RTS/CTS) on the serial port
3115 when debugging using remote targets.
3117 set mem inaccessible-by-default
3118 show mem inaccessible-by-default
3119 If the target supplies a memory map, for instance via the remote
3120 protocol's "qXfer:memory-map:read" packet, setting this variable
3121 prevents GDB from accessing memory outside the memory map. This
3122 is useful for targets with memory mapped registers or which react
3123 badly to accesses of unmapped address space.
3125 set breakpoint auto-hw
3126 show breakpoint auto-hw
3127 If the target supplies a memory map, for instance via the remote
3128 protocol's "qXfer:memory-map:read" packet, setting this variable
3129 lets GDB use hardware breakpoints automatically for memory regions
3130 where it can not use software breakpoints. This covers both the
3131 "break" command and internal breakpoints used for other commands
3132 including "next" and "finish".
3135 catch exception unhandled
3136 Stop the program execution when Ada exceptions are raised.
3139 Stop the program execution when an Ada assertion failed.
3143 Set an alternate system root for target files. This is a more
3144 general version of "set solib-absolute-prefix", which is now
3145 an alias to "set sysroot".
3148 Provide extended SPU facility status information. This set of
3149 commands is available only when debugging the Cell/B.E. SPU
3152 * New native configurations
3154 OpenBSD/sh sh*-*openbsd*
3157 unset tdesc filename
3159 Use the specified local file as an XML target description, and do
3160 not query the target for its built-in description.
3164 OpenBSD/sh sh*-*-openbsd*
3165 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3166 Toshiba Media Processor mep-elf
3168 * New remote packets
3171 Ignore the specified signals; pass them directly to the debugged program
3172 without stopping other threads or reporting them to GDB.
3174 qXfer:features:read:
3175 Read an XML target description from the target, which describes its
3180 Read or write contents of an spufs file on the target system. These
3181 packets are available only on the Cell/B.E. SPU architecture.
3183 qXfer:libraries:read:
3184 Report the loaded shared libraries. Combined with new "T" packet
3185 response, this packet allows GDB to debug shared libraries on
3186 targets where the operating system manages the list of loaded
3187 libraries (e.g. Windows and SymbianOS).
3191 Support for these obsolete configurations has been removed.
3199 i[34567]86-*-lynxos*
3200 i[34567]86-*-netware*
3201 i[34567]86-*-sco3.2v5*
3202 i[34567]86-*-sco3.2v4*
3204 i[34567]86-*-sysv4.2*
3207 i[34567]86-*-unixware2*
3208 i[34567]86-*-unixware*
3217 * Other removed features
3224 Various m68k-only ROM monitors.
3231 Various Renesas ROM monitors and debugging interfaces for SH and
3236 Support for a Macraigor serial interface to on-chip debugging.
3237 GDB does not directly support the newer parallel or USB
3242 A debug information format. The predecessor to DWARF 2 and
3243 DWARF 3, which are still supported.
3245 Support for the HP aCC compiler on HP-UX/PA-RISC
3247 SOM-encapsulated symbolic debugging information, automatic
3248 invocation of pxdb, and the aCC custom C++ ABI. This does not
3249 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3250 with aCC can still be debugged on an assembly level.
3252 MIPS ".pdr" sections
3254 A MIPS-specific format used to describe stack frame layout
3255 in debugging information.
3259 GDB could work with an older version of Guile to debug
3260 the interpreter and Scheme programs running in it.
3262 set mips stack-arg-size
3263 set mips saved-gpreg-size
3265 Use "set mips abi" to control parameter passing for MIPS.
3267 *** Changes in GDB 6.6
3272 Cell Broadband Engine SPU spu-elf
3274 * GDB can now be configured as a cross-debugger targeting native Windows
3275 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3276 running on a Windows system over TCP/IP to debug Windows programs.
3278 * The GDB remote stub, gdbserver, has been updated to support Windows and
3279 Cygwin debugging. Both single-threaded and multi-threaded programs are
3282 * The "set trust-readonly-sections" command works again. This command was
3283 broken in GDB 6.3, 6.4, and 6.5.
3285 * The "load" command now supports writing to flash memory, if the remote
3286 stub provides the required support.
3288 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3289 longer requires symbolic debug information (e.g. DWARF-2).
3294 unset substitute-path
3295 show substitute-path
3296 Manage a list of substitution rules that GDB uses to rewrite the name
3297 of the directories where the sources are located. This can be useful
3298 for instance when the sources were moved to a different location
3299 between compilation and debugging.
3303 Print each CLI command as it is executed. Each command is prefixed with
3304 a number of `+' symbols representing the nesting depth.
3305 The source command now has a `-v' option to enable the same feature.
3309 The ARM Demon monitor support (RDP protocol, "target rdp").
3311 Kernel Object Display, an embedded debugging feature which only worked with
3312 an obsolete version of Cisco IOS.
3314 The 'set download-write-size' and 'show download-write-size' commands.
3316 * New remote packets
3319 Tell a stub about GDB client features, and request remote target features.
3320 The first feature implemented is PacketSize, which allows the target to
3321 specify the size of packets it can handle - to minimize the number of
3322 packets required and improve performance when connected to a remote
3326 Fetch an OS auxilliary vector from the remote stub. This packet is a
3327 more efficient replacement for qPart:auxv:read.
3329 qXfer:memory-map:read:
3330 Fetch a memory map from the remote stub, including information about
3331 RAM, ROM, and flash memory devices.
3336 Erase and program a flash memory device.
3338 * Removed remote packets
3341 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3342 used it, and only gdbserver implemented it.
3344 *** Changes in GDB 6.5
3348 Renesas M32C/M16C m32c-elf
3350 Morpho Technologies ms1 ms1-elf
3354 init-if-undefined Initialize a convenience variable, but
3355 only if it doesn't already have a value.
3357 The following commands are presently only implemented for native GNU/Linux:
3359 checkpoint Save a snapshot of the program state.
3361 restart <n> Return the program state to a
3362 previously saved state.
3364 info checkpoints List currently saved checkpoints.
3366 delete-checkpoint <n> Delete a previously saved checkpoint.
3368 set|show detach-on-fork Tell gdb whether to detach from a newly
3369 forked process, or to keep debugging it.
3371 info forks List forks of the user program that
3372 are available to be debugged.
3374 fork <n> Switch to debugging one of several
3375 forks of the user program that are
3376 available to be debugged.
3378 delete-fork <n> Delete a fork from the list of forks
3379 that are available to be debugged (and
3380 kill the forked process).
3382 detach-fork <n> Delete a fork from the list of forks
3383 that are available to be debugged (and
3384 allow the process to continue).
3388 Morpho Technologies ms2 ms1-elf
3390 * Improved Windows host support
3392 GDB now builds as a cross debugger hosted on i686-mingw32, including
3393 native console support, and remote communications using either
3394 network sockets or serial ports.
3396 * Improved Modula-2 language support
3398 GDB can now print most types in the Modula-2 syntax. This includes:
3399 basic types, set types, record types, enumerated types, range types,
3400 pointer types and ARRAY types. Procedure var parameters are correctly
3401 printed and hexadecimal addresses and character constants are also
3402 written in the Modula-2 syntax. Best results can be obtained by using
3403 GNU Modula-2 together with the -gdwarf-2 command line option.
3407 The ARM rdi-share module.
3409 The Netware NLM debug server.
3411 *** Changes in GDB 6.4
3413 * New native configurations
3415 OpenBSD/arm arm*-*-openbsd*
3416 OpenBSD/mips64 mips64-*-openbsd*
3420 Morpho Technologies ms1 ms1-elf
3422 * New command line options
3424 --batch-silent As for --batch, but totally silent.
3425 --return-child-result The debugger will exist with the same value
3426 the child (debugged) program exited with.
3427 --eval-command COMMAND, -ex COMMAND
3428 Execute a single GDB CLI command. This may be
3429 specified multiple times and in conjunction
3430 with the --command (-x) option.
3432 * Deprecated commands removed
3434 The following commands, that were deprecated in 2000, have been
3438 set|show arm disassembly-flavor set|show arm disassembler
3439 othernames set arm disassembler
3440 set|show remotedebug set|show debug remote
3441 set|show archdebug set|show debug arch
3442 set|show eventdebug set|show debug event
3445 * New BSD user-level threads support
3447 It is now possible to debug programs using the user-level threads
3448 library on OpenBSD and FreeBSD. Currently supported (target)
3451 FreeBSD/amd64 x86_64-*-freebsd*
3452 FreeBSD/i386 i386-*-freebsd*
3453 OpenBSD/i386 i386-*-openbsd*
3455 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3456 are not yet supported.
3458 * New support for Matsushita MN10300 w/sim added
3459 (Work in progress). mn10300-elf.
3461 * REMOVED configurations and files
3463 VxWorks and the XDR protocol *-*-vxworks
3464 Motorola MCORE mcore-*-*
3465 National Semiconductor NS32000 ns32k-*-*
3467 * New "set print array-indexes" command
3469 After turning this setting "on", GDB prints the index of each element
3470 when displaying arrays. The default is "off" to preserve the previous
3473 * VAX floating point support
3475 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3477 * User-defined command support
3479 In addition to using $arg0..$arg9 for argument passing, it is now possible
3480 to use $argc to determine now many arguments have been passed. See the
3481 section on user-defined commands in the user manual for more information.
3483 *** Changes in GDB 6.3:
3485 * New command line option
3487 GDB now accepts -l followed by a number to set the timeout for remote
3490 * GDB works with GCC -feliminate-dwarf2-dups
3492 GDB now supports a more compact representation of DWARF-2 debug
3493 information using DW_FORM_ref_addr references. These are produced
3494 by GCC with the option -feliminate-dwarf2-dups and also by some
3495 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3496 to use -feliminate-dwarf2-dups.
3498 * Internationalization
3500 When supported by the host system, GDB will be built with
3501 internationalization (libintl). The task of marking up the sources is
3502 continued, we're looking forward to our first translation.
3506 Initial support for debugging programs compiled with the GNAT
3507 implementation of the Ada programming language has been integrated
3508 into GDB. In this release, support is limited to expression evaluation.
3510 * New native configurations
3512 GNU/Linux/m32r m32r-*-linux-gnu
3516 GDB's remote protocol now includes support for the 'p' packet. This
3517 packet is used to fetch individual registers from a remote inferior.
3519 * END-OF-LIFE registers[] compatibility module
3521 GDB's internal register infrastructure has been completely rewritten.
3522 The new infrastructure making possible the implementation of key new
3523 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3526 GDB 6.3 will be the last release to include the the registers[]
3527 compatibility module that allowed out-of-date configurations to
3528 continue to work. This change directly impacts the following
3538 powerpc bdm protocol
3540 Unless there is activity to revive these configurations, they will be
3541 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3543 * OBSOLETE configurations and files
3545 Configurations that have been declared obsolete in this release have
3546 been commented out. Unless there is activity to revive these
3547 configurations, the next release of GDB will have their sources
3548 permanently REMOVED.
3557 *** Changes in GDB 6.2.1:
3559 * MIPS `break main; run' gave an heuristic-fence-post warning
3561 When attempting to run even a simple program, a warning about
3562 heuristic-fence-post being hit would be reported. This problem has
3565 * MIPS IRIX 'long double' crashed GDB
3567 When examining a long double variable, GDB would get a segmentation
3568 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3569 IRIX long double values).
3573 A bug in the VAX stack code was causing problems with the "next"
3574 command. This problem has been fixed.
3576 *** Changes in GDB 6.2:
3578 * Fix for ``many threads''
3580 On GNU/Linux systems that use the NPTL threads library, a program
3581 rapidly creating and deleting threads would confuse GDB leading to the
3584 ptrace: No such process.
3585 thread_db_get_info: cannot get thread info: generic error
3587 This problem has been fixed.
3589 * "-async" and "-noasync" options removed.
3591 Support for the broken "-noasync" option has been removed (it caused
3594 * New ``start'' command.
3596 This command runs the program until the begining of the main procedure.
3598 * New BSD Kernel Data Access Library (libkvm) interface
3600 Using ``target kvm'' it is now possible to debug kernel core dumps and
3601 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3602 platforms. Currently supported (native-only) configurations are:
3604 FreeBSD/amd64 x86_64-*-freebsd*
3605 FreeBSD/i386 i?86-*-freebsd*
3606 NetBSD/i386 i?86-*-netbsd*
3607 NetBSD/m68k m68*-*-netbsd*
3608 NetBSD/sparc sparc-*-netbsd*
3609 OpenBSD/amd64 x86_64-*-openbsd*
3610 OpenBSD/i386 i?86-*-openbsd*
3611 OpenBSD/m68k m68*-openbsd*
3612 OpenBSD/sparc sparc-*-openbsd*
3614 * Signal trampoline code overhauled
3616 Many generic problems with GDB's signal handling code have been fixed.
3617 These include: backtraces through non-contiguous stacks; recognition
3618 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3619 call; backtrace through a signal trampoline; step into and out of
3620 signal handlers; and single-stepping in the signal trampoline.
3622 Please note that kernel bugs are a limiting factor here. These
3623 features have been shown to work on an s390 GNU/Linux system that
3624 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3626 * Cygwin support for DWARF 2 added.
3628 * New native configurations
3630 GNU/Linux/hppa hppa*-*-linux*
3631 OpenBSD/hppa hppa*-*-openbsd*
3632 OpenBSD/m68k m68*-*-openbsd*
3633 OpenBSD/m88k m88*-*-openbsd*
3634 OpenBSD/powerpc powerpc-*-openbsd*
3635 NetBSD/vax vax-*-netbsd*
3636 OpenBSD/vax vax-*-openbsd*
3638 * END-OF-LIFE frame compatibility module
3640 GDB's internal frame infrastructure has been completely rewritten.
3641 The new infrastructure making it possible to support key new features
3642 including DWARF 2 Call Frame Information. To aid in the task of
3643 migrating old configurations to this new infrastructure, a
3644 compatibility module, that allowed old configurations to continue to
3645 work, was also included.
3647 GDB 6.2 will be the last release to include this frame compatibility
3648 module. This change directly impacts the following configurations:
3658 Unless there is activity to revive these configurations, they will be
3659 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3661 * REMOVED configurations and files
3663 Sun 3, running SunOS 3 m68*-*-sunos3*
3664 Sun 3, running SunOS 4 m68*-*-sunos4*
3665 Sun 2, running SunOS 3 m68000-*-sunos3*
3666 Sun 2, running SunOS 4 m68000-*-sunos4*
3667 Motorola 680x0 running LynxOS m68*-*-lynxos*
3668 AT&T 3b1/Unix pc m68*-att-*
3669 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3670 decstation mips-dec-* mips-little-*
3671 riscos mips-*-riscos* mips-*-sysv*
3672 sonymips mips-sony-*
3673 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3675 *** Changes in GDB 6.1.1:
3677 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3679 The TUI (Text-mode User Interface) is now built as part of a default
3680 GDB configuration. It is enabled by either selecting the TUI with the
3681 command line option "-i=tui" or by running the separate "gdbtui"
3682 program. For more information on the TUI, see the manual "Debugging
3685 * Pending breakpoint support (also included in GDB 6.1)
3687 Support has been added to allow you to specify breakpoints in shared
3688 libraries that have not yet been loaded. If a breakpoint location
3689 cannot be found, and the "breakpoint pending" option is set to auto,
3690 GDB queries you if you wish to make the breakpoint pending on a future
3691 shared-library load. If and when GDB resolves the breakpoint symbol,
3692 the pending breakpoint is removed as one or more regular breakpoints
3695 Pending breakpoints are very useful for GCJ Java debugging.
3697 * Fixed ISO-C build problems
3699 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3700 non ISO-C code that stopped them being built using a more strict ISO-C
3701 compiler (e.g., IBM's C compiler).
3703 * Fixed build problem on IRIX 5
3705 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3706 wasn't able to compile compile on an IRIX 5 system.
3708 * Added execute permission to gdb/gdbserver/configure
3710 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3711 permission. This bug would cause configure to fail on a number of
3712 systems (Solaris, IRIX). Ref: server/519.
3714 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3716 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3717 has been updated to use constant array sizes.
3719 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3721 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3722 its generated DWARF Call Frame Info. This encoding was causing GDB to
3723 panic, that panic has been fixed. Ref: gdb/1628.
3725 * Fixed a problem when examining parameters in shared library code.
3727 When examining parameters in optimized shared library code generated
3728 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3729 not available''. GDB now correctly displays the variable's value.
3731 *** Changes in GDB 6.1:
3733 * Removed --with-mmalloc
3735 Support for the mmalloc memory manager has been removed, as it
3736 conflicted with the internal gdb byte cache.
3738 * Changes in AMD64 configurations
3740 The AMD64 target now includes the %cs and %ss registers. As a result
3741 the AMD64 remote protocol has changed; this affects the floating-point
3742 and SSE registers. If you rely on those registers for your debugging,
3743 you should upgrade gdbserver on the remote side.
3745 * Revised SPARC target
3747 The SPARC target has been completely revised, incorporating the
3748 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3749 support for LynxOS and SunOS 4 has been dropped. Calling functions
3750 from within GDB on operating systems with a non-executable stack
3751 (Solaris, OpenBSD) now works.
3755 GDB has a new C++ demangler which does a better job on the mangled
3756 names generated by current versions of g++. It also runs faster, so
3757 with this and other changes gdb should now start faster on large C++
3760 * DWARF 2 Location Expressions
3762 GDB support for location expressions has been extended to support function
3763 arguments and frame bases. Older versions of GDB could crash when they
3766 * C++ nested types and namespaces
3768 GDB's support for nested types and namespaces in C++ has been
3769 improved, especially if you use the DWARF 2 debugging format. (This
3770 is the default for recent versions of GCC on most platforms.)
3771 Specifically, if you have a class "Inner" defined within a class or
3772 namespace "Outer", then GDB realizes that the class's name is
3773 "Outer::Inner", not simply "Inner". This should greatly reduce the
3774 frequency of complaints about not finding RTTI symbols. In addition,
3775 if you are stopped at inside of a function defined within a namespace,
3776 GDB modifies its name lookup accordingly.
3778 * New native configurations
3780 NetBSD/amd64 x86_64-*-netbsd*
3781 OpenBSD/amd64 x86_64-*-openbsd*
3782 OpenBSD/alpha alpha*-*-openbsd*
3783 OpenBSD/sparc sparc-*-openbsd*
3784 OpenBSD/sparc64 sparc64-*-openbsd*
3786 * New debugging protocols
3788 M32R with SDI protocol m32r-*-elf*
3790 * "set prompt-escape-char" command deleted.
3792 The command "set prompt-escape-char" has been deleted. This command,
3793 and its very obscure effet on GDB's prompt, was never documented,
3794 tested, nor mentioned in the NEWS file.
3796 * OBSOLETE configurations and files
3798 Configurations that have been declared obsolete in this release have
3799 been commented out. Unless there is activity to revive these
3800 configurations, the next release of GDB will have their sources
3801 permanently REMOVED.
3803 Sun 3, running SunOS 3 m68*-*-sunos3*
3804 Sun 3, running SunOS 4 m68*-*-sunos4*
3805 Sun 2, running SunOS 3 m68000-*-sunos3*
3806 Sun 2, running SunOS 4 m68000-*-sunos4*
3807 Motorola 680x0 running LynxOS m68*-*-lynxos*
3808 AT&T 3b1/Unix pc m68*-att-*
3809 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3810 decstation mips-dec-* mips-little-*
3811 riscos mips-*-riscos* mips-*-sysv*
3812 sonymips mips-sony-*
3813 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3815 * REMOVED configurations and files
3817 SGI Irix-4.x mips-sgi-irix4 or iris4
3818 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3819 Z8000 simulator z8k-zilog-none or z8ksim
3820 Matsushita MN10200 w/simulator mn10200-*-*
3821 H8/500 simulator h8500-hitachi-hms or h8500hms
3822 HP/PA running BSD hppa*-*-bsd*
3823 HP/PA running OSF/1 hppa*-*-osf*
3824 HP/PA Pro target hppa*-*-pro*
3825 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3826 386BSD i[3456]86-*-bsd*
3827 Sequent family i[3456]86-sequent-sysv4*
3828 i[3456]86-sequent-sysv*
3829 i[3456]86-sequent-bsd*
3830 SPARC running LynxOS sparc-*-lynxos*
3831 SPARC running SunOS 4 sparc-*-sunos4*
3832 Tsqware Sparclet sparclet-*-*
3833 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3835 *** Changes in GDB 6.0:
3839 Support for debugging the Objective-C programming language has been
3840 integrated into GDB.
3842 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3844 DWARF 2's Call Frame Information makes available compiler generated
3845 information that more exactly describes the program's run-time stack.
3846 By using this information, GDB is able to provide more robust stack
3849 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3850 have been updated to use a new backtrace mechanism which includes
3851 DWARF 2 CFI support.
3855 GDB's remote protocol has been extended to include support for hosted
3856 file I/O (where the remote target uses GDB's file system). See GDB's
3857 remote protocol documentation for details.
3859 * All targets using the new architecture framework.
3861 All of GDB's targets have been updated to use the new internal
3862 architecture framework. The way is now open for future GDB releases
3863 to include cross-architecture native debugging support (i386 on amd64,
3866 * GNU/Linux's Thread Local Storage (TLS)
3868 GDB now includes support for for the GNU/Linux implementation of
3869 per-thread variables.
3871 * GNU/Linux's Native POSIX Thread Library (NPTL)
3873 GDB's thread code has been updated to work with either the new
3874 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3876 * Separate debug info.
3878 GDB, in conjunction with BINUTILS, now supports a mechanism for
3879 automatically loading debug information from a separate file. Instead
3880 of shipping full debug and non-debug versions of system libraries,
3881 system integrators can now instead ship just the stripped libraries
3882 and optional debug files.
3884 * DWARF 2 Location Expressions
3886 DWARF 2 Location Expressions allow the compiler to more completely
3887 describe the location of variables (even in optimized code) to the
3890 GDB now includes preliminary support for location expressions (support
3891 for DW_OP_piece is still missing).
3895 A number of long standing bugs that caused GDB to die while starting a
3896 Java application have been fixed. GDB's Java support is now
3897 considered "useable".
3899 * GNU/Linux support for fork, vfork, and exec.
3901 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3902 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3905 * GDB supports logging output to a file
3907 There are two new commands, "set logging" and "show logging", which can be
3908 used to capture GDB's output to a file.
3910 * The meaning of "detach" has changed for gdbserver
3912 The "detach" command will now resume the application, as documented. To
3913 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3916 * d10v, m68hc11 `regs' command deprecated
3918 The `info registers' command has been updated so that it displays the
3919 registers using a format identical to the old `regs' command.
3923 A new command, "maint set profile on/off", has been added. This command can
3924 be used to enable or disable profiling while running GDB, to profile a
3925 session or a set of commands. In addition there is a new configure switch,
3926 "--enable-profiling", which will cause GDB to be compiled with profiling
3927 data, for more informative profiling results.
3929 * Default MI syntax changed to "mi2".
3931 The default MI (machine interface) syntax, enabled by the command line
3932 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3933 "mi1", can be enabled by specifying the option "-i=mi1".
3935 Support for the original "mi0" syntax (included in GDB 5.0) has been
3938 Fix for gdb/192: removed extraneous space when displaying frame level.
3939 Fix for gdb/672: update changelist is now output in mi list format.
3940 Fix for gdb/702: a -var-assign that updates the value now shows up
3941 in a subsequent -var-update.
3943 * New native configurations.
3945 FreeBSD/amd64 x86_64-*-freebsd*
3947 * Multi-arched targets.
3949 HP/PA HPUX11 hppa*-*-hpux*
3950 Renesas M32R/D w/simulator m32r-*-elf*
3952 * OBSOLETE configurations and files
3954 Configurations that have been declared obsolete in this release have
3955 been commented out. Unless there is activity to revive these
3956 configurations, the next release of GDB will have their sources
3957 permanently REMOVED.
3959 Z8000 simulator z8k-zilog-none or z8ksim
3960 Matsushita MN10200 w/simulator mn10200-*-*
3961 H8/500 simulator h8500-hitachi-hms or h8500hms
3962 HP/PA running BSD hppa*-*-bsd*
3963 HP/PA running OSF/1 hppa*-*-osf*
3964 HP/PA Pro target hppa*-*-pro*
3965 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3966 Sequent family i[3456]86-sequent-sysv4*
3967 i[3456]86-sequent-sysv*
3968 i[3456]86-sequent-bsd*
3969 Tsqware Sparclet sparclet-*-*
3970 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3972 * REMOVED configurations and files
3975 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3976 IBM AIX PS/2 i[3456]86-*-aix
3977 i386 running Mach 3.0 i[3456]86-*-mach3*
3978 i386 running Mach i[3456]86-*-mach*
3979 i386 running OSF/1 i[3456]86-*osf1mk*
3980 HP/Apollo 68k Family m68*-apollo*-sysv*,
3982 m68*-hp-bsd*, m68*-hp-hpux*
3983 Argonaut Risc Chip (ARC) arc-*-*
3984 Mitsubishi D30V d30v-*-*
3985 Fujitsu FR30 fr30-*-elf*
3986 OS/9000 i[34]86-*-os9k
3987 I960 with MON960 i960-*-coff
3989 * MIPS $fp behavior changed
3991 The convenience variable $fp, for the MIPS, now consistently returns
3992 the address of the current frame's base. Previously, depending on the
3993 context, $fp could refer to either $sp or the current frame's base
3994 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3995 The GNU Source-Level Debugger''.
3997 *** Changes in GDB 5.3:
3999 * GNU/Linux shared library multi-threaded performance improved.
4001 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4002 `/proc', in preference to `ptrace' for memory reads. This may result
4003 in an improvement in the start-up time of multi-threaded, shared
4004 library applications when run under GDB. One GDB user writes: ``loads
4005 shared libs like mad''.
4007 * ``gdbserver'' now supports multi-threaded applications on some targets
4009 Support for debugging multi-threaded applications which use
4010 the GNU/Linux LinuxThreads package has been added for
4011 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4012 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4014 * GDB now supports C/C++ preprocessor macros.
4016 GDB now expands preprocessor macro invocations in C/C++ expressions,
4017 and provides various commands for showing macro definitions and how
4020 The new command `macro expand EXPRESSION' expands any macro
4021 invocations in expression, and shows the result.
4023 The new command `show macro MACRO-NAME' shows the definition of the
4024 macro named MACRO-NAME, and where it was defined.
4026 Most compilers don't include information about macros in the debugging
4027 information by default. In GCC 3.1, for example, you need to compile
4028 your program with the options `-gdwarf-2 -g3'. If the macro
4029 information is present in the executable, GDB will read it.
4031 * Multi-arched targets.
4033 DEC Alpha (partial) alpha*-*-*
4034 DEC VAX (partial) vax-*-*
4036 National Semiconductor NS32000 (partial) ns32k-*-*
4037 Motorola 68000 (partial) m68k-*-*
4038 Motorola MCORE mcore-*-*
4042 Fujitsu FRV architecture added by Red Hat frv*-*-*
4045 * New native configurations
4047 Alpha NetBSD alpha*-*-netbsd*
4048 SH NetBSD sh*-*-netbsdelf*
4049 MIPS NetBSD mips*-*-netbsd*
4050 UltraSPARC NetBSD sparc64-*-netbsd*
4052 * OBSOLETE configurations and files
4054 Configurations that have been declared obsolete in this release have
4055 been commented out. Unless there is activity to revive these
4056 configurations, the next release of GDB will have their sources
4057 permanently REMOVED.
4059 Mitsubishi D30V d30v-*-*
4060 OS/9000 i[34]86-*-os9k
4061 IBM AIX PS/2 i[3456]86-*-aix
4062 Fujitsu FR30 fr30-*-elf*
4063 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4064 Argonaut Risc Chip (ARC) arc-*-*
4065 i386 running Mach 3.0 i[3456]86-*-mach3*
4066 i386 running Mach i[3456]86-*-mach*
4067 i386 running OSF/1 i[3456]86-*osf1mk*
4068 HP/Apollo 68k Family m68*-apollo*-sysv*,
4070 m68*-hp-bsd*, m68*-hp-hpux*
4071 I960 with MON960 i960-*-coff
4073 * OBSOLETE languages
4075 CHILL, a Pascal like language used by telecommunications companies.
4077 * REMOVED configurations and files
4079 AMD 29k family via UDI a29k-amd-udi, udi29k
4080 A29K VxWorks a29k-*-vxworks
4081 AMD 29000 embedded, using EBMON a29k-none-none
4082 AMD 29000 embedded with COFF a29k-none-coff
4083 AMD 29000 embedded with a.out a29k-none-aout
4085 testsuite/gdb.hp/gdb.threads-hp/ directory
4087 * New command "set max-user-call-depth <nnn>"
4089 This command allows the user to limit the call depth of user-defined
4090 commands. The default is 1024.
4092 * Changes in FreeBSD/i386 native debugging.
4094 Support for the "generate-core-file" has been added.
4096 * New commands "dump", "append", and "restore".
4098 These commands allow data to be copied from target memory
4099 to a bfd-format or binary file (dump and append), and back
4100 from a file into memory (restore).
4102 * Improved "next/step" support on multi-processor Alpha Tru64.
4104 The previous single-step mechanism could cause unpredictable problems,
4105 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4106 of a software single-step mechanism prevents this.
4108 *** Changes in GDB 5.2.1:
4116 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4117 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4118 Fix, by Joel Brobecker imported from mainline.
4120 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4121 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4122 Fix, by Fred Fish, imported from mainline.
4124 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4125 Surprisingly enough, it works now.
4126 By Michal Ludvig, imported from mainline.
4128 i386 hardware watchpoint support:
4129 avoid misses on second run for some targets.
4130 By Pierre Muller, imported from mainline.
4132 *** Changes in GDB 5.2:
4134 * New command "set trust-readonly-sections on[off]".
4136 This command is a hint that tells gdb that read-only sections
4137 really are read-only (ie. that their contents will not change).
4138 In this mode, gdb will go to the object file rather than the
4139 target to read memory from read-only sections (such as ".text").
4140 This can be a significant performance improvement on some
4141 (notably embedded) targets.
4143 * New command "generate-core-file" (or "gcore").
4145 This new gdb command allows the user to drop a core file of the child
4146 process state at any time. So far it's been implemented only for
4147 GNU/Linux and Solaris, but should be relatively easily ported to other
4148 hosts. Argument is core file name (defaults to core.<pid>).
4150 * New command line option
4152 GDB now accepts --pid or -p followed by a process id.
4154 * Change in command line behavior -- corefiles vs. process ids.
4156 There is a subtle behavior in the way in which GDB handles
4157 command line arguments. The first non-flag argument is always
4158 a program to debug, but the second non-flag argument may either
4159 be a corefile or a process id. Previously, GDB would attempt to
4160 open the second argument as a corefile, and if that failed, would
4161 issue a superfluous error message and then attempt to attach it as
4162 a process. Now, if the second argument begins with a non-digit,
4163 it will be treated as a corefile. If it begins with a digit,
4164 GDB will attempt to attach it as a process, and if no such process
4165 is found, will then attempt to open it as a corefile.
4167 * Changes in ARM configurations.
4169 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4170 configuration is fully multi-arch.
4172 * New native configurations
4174 ARM NetBSD arm*-*-netbsd*
4175 x86 OpenBSD i[3456]86-*-openbsd*
4176 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4177 Sparc64 running FreeBSD sparc64-*-freebsd*
4181 Sanyo XStormy16 xstormy16-elf
4183 * OBSOLETE configurations and files
4185 Configurations that have been declared obsolete in this release have
4186 been commented out. Unless there is activity to revive these
4187 configurations, the next release of GDB will have their sources
4188 permanently REMOVED.
4190 AMD 29k family via UDI a29k-amd-udi, udi29k
4191 A29K VxWorks a29k-*-vxworks
4192 AMD 29000 embedded, using EBMON a29k-none-none
4193 AMD 29000 embedded with COFF a29k-none-coff
4194 AMD 29000 embedded with a.out a29k-none-aout
4196 testsuite/gdb.hp/gdb.threads-hp/ directory
4198 * REMOVED configurations and files
4200 TI TMS320C80 tic80-*-*
4202 PowerPC Solaris powerpcle-*-solaris*
4203 PowerPC Windows NT powerpcle-*-cygwin32
4204 PowerPC Netware powerpc-*-netware*
4205 Harris/CXUX m88k m88*-harris-cxux*
4206 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4207 ns32k-utek-sysv* ns32k-utek-*
4208 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4209 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4210 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4211 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4212 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4214 * Changes to command line processing
4216 The new `--args' feature can be used to specify command-line arguments
4217 for the inferior from gdb's command line.
4219 * Changes to key bindings
4221 There is a new `operate-and-get-next' function bound to `C-o'.
4223 *** Changes in GDB 5.1.1
4225 Fix compile problem on DJGPP.
4227 Fix a problem with floating-point registers on the i386 being
4230 Fix to stop GDB crashing on .debug_str debug info.
4232 Numerous documentation fixes.
4234 Numerous testsuite fixes.
4236 *** Changes in GDB 5.1:
4238 * New native configurations
4240 Alpha FreeBSD alpha*-*-freebsd*
4241 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4242 MIPS GNU/Linux mips*-*-linux*
4243 MIPS SGI Irix 6.x mips*-sgi-irix6*
4244 ia64 AIX ia64-*-aix*
4245 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4249 Motorola 68HC11 and 68HC12 m68hc11-elf
4251 UltraSparc running GNU/Linux sparc64-*-linux*
4253 * OBSOLETE configurations and files
4255 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4256 Harris/CXUX m88k m88*-harris-cxux*
4257 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4258 ns32k-utek-sysv* ns32k-utek-*
4259 TI TMS320C80 tic80-*-*
4261 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4262 PowerPC Solaris powerpcle-*-solaris*
4263 PowerPC Windows NT powerpcle-*-cygwin32
4264 PowerPC Netware powerpc-*-netware*
4265 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4266 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4267 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4268 Apple Macintosh (MPW) host N/A
4270 stuff.c (Program to stuff files into a specially prepared space in kdb)
4271 kdb-start.c (Main loop for the standalone kernel debugger)
4273 Configurations that have been declared obsolete in this release have
4274 been commented out. Unless there is activity to revive these
4275 configurations, the next release of GDB will have their sources
4276 permanently REMOVED.
4278 * REMOVED configurations and files
4280 Altos 3068 m68*-altos-*
4281 Convex c1-*-*, c2-*-*
4283 ARM RISCix arm-*-* (as host)
4287 * GDB has been converted to ISO C.
4289 GDB's source code has been converted to ISO C. In particular, the
4290 sources are fully protoized, and rely on standard headers being
4295 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4297 * The MI enabled by default.
4299 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4300 revised and enabled by default. Packages which use GDB as a debugging
4301 engine behind a UI or another front end are encouraged to switch to
4302 using the GDB/MI interface, instead of the old annotations interface
4303 which is now deprecated.
4305 * Support for debugging Pascal programs.
4307 GDB now includes support for debugging Pascal programs. The following
4308 main features are supported:
4310 - Pascal-specific data types such as sets;
4312 - automatic recognition of Pascal sources based on file-name
4315 - Pascal-style display of data types, variables, and functions;
4317 - a Pascal expression parser.
4319 However, some important features are not yet supported.
4321 - Pascal string operations are not supported at all;
4323 - there are some problems with boolean types;
4325 - Pascal type hexadecimal constants are not supported
4326 because they conflict with the internal variables format;
4328 - support for Pascal objects and classes is not full yet;
4330 - unlike Pascal, GDB is case-sensitive for symbol names.
4332 * Changes in completion.
4334 Commands such as `shell', `run' and `set args', which pass arguments
4335 to inferior programs, now complete on file names, similar to what
4336 users expect at the shell prompt.
4338 Commands which accept locations, such as `disassemble', `print',
4339 `breakpoint', `until', etc. now complete on filenames as well as
4340 program symbols. Thus, if you type "break foob TAB", and the source
4341 files linked into the programs include `foobar.c', that file name will
4342 be one of the candidates for completion. However, file names are not
4343 considered for completion after you typed a colon that delimits a file
4344 name from a name of a function in that file, as in "break foo.c:bar".
4346 `set demangle-style' completes on available demangling styles.
4348 * New platform-independent commands:
4350 It is now possible to define a post-hook for a command as well as a
4351 hook that runs before the command. For more details, see the
4352 documentation of `hookpost' in the GDB manual.
4354 * Changes in GNU/Linux native debugging.
4356 Support for debugging multi-threaded programs has been completely
4357 revised for all platforms except m68k and sparc. You can now debug as
4358 many threads as your system allows you to have.
4360 Attach/detach is supported for multi-threaded programs.
4362 Support for SSE registers was added for x86. This doesn't work for
4363 multi-threaded programs though.
4365 * Changes in MIPS configurations.
4367 Multi-arch support is enabled for all MIPS configurations.
4369 GDB can now be built as native debugger on SGI Irix 6.x systems for
4370 debugging n32 executables. (Debugging 64-bit executables is not yet
4373 * Unified support for hardware watchpoints in all x86 configurations.
4375 Most (if not all) native x86 configurations support hardware-assisted
4376 breakpoints and watchpoints in a unified manner. This support
4377 implements debug register sharing between watchpoints, which allows to
4378 put a virtually infinite number of watchpoints on the same address,
4379 and also supports watching regions up to 16 bytes with several debug
4382 The new maintenance command `maintenance show-debug-regs' toggles
4383 debugging print-outs in functions that insert, remove, and test
4384 watchpoints and hardware breakpoints.
4386 * Changes in the DJGPP native configuration.
4388 New command ``info dos sysinfo'' displays assorted information about
4389 the CPU, OS, memory, and DPMI server.
4391 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4392 display information about segment descriptors stored in GDT, LDT, and
4395 New commands ``info dos pde'' and ``info dos pte'' display entries
4396 from Page Directory and Page Tables (for now works with CWSDPMI only).
4397 New command ``info dos address-pte'' displays the Page Table entry for
4398 a given linear address.
4400 GDB can now pass command lines longer than 126 characters to the
4401 program being debugged (requires an update to the libdbg.a library
4402 which is part of the DJGPP development kit).
4404 DWARF2 debug info is now supported.
4406 It is now possible to `step' and `next' through calls to `longjmp'.
4408 * Changes in documentation.
4410 All GDB documentation was converted to GFDL, the GNU Free
4411 Documentation License.
4413 Tracepoints-related commands are now fully documented in the GDB
4416 TUI, the Text-mode User Interface, is now documented in the manual.
4418 Tracepoints-related commands are now fully documented in the GDB
4421 The "GDB Internals" manual now has an index. It also includes
4422 documentation of `ui_out' functions, GDB coding standards, x86
4423 hardware watchpoints, and memory region attributes.
4425 * GDB's version number moved to ``version.in''
4427 The Makefile variable VERSION has been replaced by the file
4428 ``version.in''. People creating GDB distributions should update the
4429 contents of this file.
4433 GUD support is now a standard part of the EMACS distribution.
4435 *** Changes in GDB 5.0:
4437 * Improved support for debugging FP programs on x86 targets
4439 Unified and much-improved support for debugging floating-point
4440 programs on all x86 targets. In particular, ``info float'' now
4441 displays the FP registers in the same format on all x86 targets, with
4442 greater level of detail.
4444 * Improvements and bugfixes in hardware-assisted watchpoints
4446 It is now possible to watch array elements, struct members, and
4447 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4448 on x86 targets no longer erroneously trigger when the address is
4451 * Improvements in the native DJGPP version of GDB
4453 The distribution now includes all the scripts and auxiliary files
4454 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4455 machines ``out of the box''.
4457 The DJGPP version can now debug programs that use signals. It is
4458 possible to catch signals that happened in the debuggee, deliver
4459 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4460 would kill the program being debugged.) Programs that hook hardware
4461 interrupts (keyboard, timer, etc.) can also be debugged.
4463 It is now possible to debug DJGPP programs that redirect their
4464 standard handles or switch them to raw (as opposed to cooked) mode, or
4465 even close them. The command ``run < foo > bar'' works as expected,
4466 and ``info terminal'' reports useful information about the debuggee's
4467 terminal, including raw/cooked mode, redirection, etc.
4469 The DJGPP version now uses termios functions for console I/O, which
4470 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4473 DOS-style file names with drive letters are now fully supported by
4476 It is now possible to debug DJGPP programs that switch their working
4477 directory. It is also possible to rerun the debuggee any number of
4478 times without restarting GDB; thus, you can use the same setup,
4479 breakpoints, etc. for many debugging sessions.
4481 * New native configurations
4483 ARM GNU/Linux arm*-*-linux*
4484 PowerPC GNU/Linux powerpc-*-linux*
4488 Motorola MCore mcore-*-*
4489 x86 VxWorks i[3456]86-*-vxworks*
4490 PowerPC VxWorks powerpc-*-vxworks*
4491 TI TMS320C80 tic80-*-*
4493 * OBSOLETE configurations
4495 Altos 3068 m68*-altos-*
4496 Convex c1-*-*, c2-*-*
4498 ARM RISCix arm-*-* (as host)
4501 Configurations that have been declared obsolete will be commented out,
4502 but the code will be left in place. If there is no activity to revive
4503 these configurations before the next release of GDB, the sources will
4504 be permanently REMOVED.
4506 * Gould support removed
4508 Support for the Gould PowerNode and NP1 has been removed.
4510 * New features for SVR4
4512 On SVR4 native platforms (such as Solaris), if you attach to a process
4513 without first loading a symbol file, GDB will now attempt to locate and
4514 load symbols from the running process's executable file.
4516 * Many C++ enhancements
4518 C++ support has been greatly improved. Overload resolution now works properly
4519 in almost all cases. RTTI support is on the way.
4521 * Remote targets can connect to a sub-program
4523 A popen(3) style serial-device has been added. This device starts a
4524 sub-process (such as a stand-alone simulator) and then communicates
4525 with that. The sub-program to run is specified using the syntax
4526 ``|<program> <args>'' vis:
4528 (gdb) set remotedebug 1
4529 (gdb) target extended-remote |mn10300-elf-sim program-args
4531 * MIPS 64 remote protocol
4533 A long standing bug in the mips64 remote protocol where by GDB
4534 expected certain 32 bit registers (ex SR) to be transfered as 32
4535 instead of 64 bits has been fixed.
4537 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4538 added to provide backward compatibility with older versions of GDB.
4540 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4542 The command ``set remotebinarydownload'' command has been replaced by
4543 ``set remote X-packet''. Other commands in ``set remote'' family
4544 include ``set remote P-packet''.
4546 * Breakpoint commands accept ranges.
4548 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4549 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4550 ``tracepoint passcount'' also accepts a range of tracepoints.
4552 * ``apropos'' command added.
4554 The ``apropos'' command searches through command names and
4555 documentation strings, printing out matches, making it much easier to
4556 try to find a command that does what you are looking for.
4560 A new machine oriented interface (MI) has been added to GDB. This
4561 interface is designed for debug environments running GDB as a separate
4562 process. This is part of the long term libGDB project. See the
4563 "GDB/MI" chapter of the GDB manual for further information. It can be
4564 enabled by configuring with:
4566 .../configure --enable-gdbmi
4568 *** Changes in GDB-4.18:
4570 * New native configurations
4572 HP-UX 10.20 hppa*-*-hpux10.20
4573 HP-UX 11.x hppa*-*-hpux11.0*
4574 M68K GNU/Linux m68*-*-linux*
4578 Fujitsu FR30 fr30-*-elf*
4579 Intel StrongARM strongarm-*-*
4580 Mitsubishi D30V d30v-*-*
4582 * OBSOLETE configurations
4584 Gould PowerNode, NP1 np1-*-*, pn-*-*
4586 Configurations that have been declared obsolete will be commented out,
4587 but the code will be left in place. If there is no activity to revive
4588 these configurations before the next release of GDB, the sources will
4589 be permanently REMOVED.
4593 As a compatibility experiment, GDB's source files buildsym.h and
4594 buildsym.c have been converted to pure standard C, no longer
4595 containing any K&R compatibility code. We believe that all systems in
4596 use today either come with a standard C compiler, or have a GCC port
4597 available. If this is not true, please report the affected
4598 configuration to bug-gdb@gnu.org immediately. See the README file for
4599 information about getting a standard C compiler if you don't have one
4604 GDB now uses readline 2.2.
4606 * set extension-language
4608 You can now control the mapping between filename extensions and source
4609 languages by using the `set extension-language' command. For instance,
4610 you can ask GDB to treat .c files as C++ by saying
4611 set extension-language .c c++
4612 The command `info extensions' lists all of the recognized extensions
4613 and their associated languages.
4615 * Setting processor type for PowerPC and RS/6000
4617 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4618 you can use the `set processor' command to specify what variant of the
4619 PowerPC family you are debugging. The command
4623 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4624 following PowerPC and RS6000 variants:
4626 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4627 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4629 403GC IBM PowerPC 403GC
4630 505 Motorola PowerPC 505
4631 860 Motorola PowerPC 860 or 850
4632 601 Motorola PowerPC 601
4633 602 Motorola PowerPC 602
4634 603 Motorola/IBM PowerPC 603 or 603e
4635 604 Motorola PowerPC 604 or 604e
4636 750 Motorola/IBM PowerPC 750 or 750
4638 At the moment, this command just tells GDB what to name the
4639 special-purpose processor registers. Since almost all the affected
4640 registers are inaccessible to user-level programs, this command is
4641 only useful for remote debugging in its present form.
4645 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4646 more extensive support for HP-UX. Added features include shared
4647 library support, kernel threads and hardware watchpoints for 11.00,
4648 support for HP's ANSI C and C++ compilers, and a compatibility mode
4649 for xdb and dbx commands.
4653 HP's donation includes the new concept of catchpoints, which is a
4654 generalization of the old catch command. On HP-UX, it is now possible
4655 to catch exec, fork, and vfork, as well as library loading.
4657 This means that the existing catch command has changed; its first
4658 argument now specifies the type of catch to be set up. See the
4659 output of "help catch" for a list of catchpoint types.
4661 * Debugging across forks
4663 On HP-UX, you can choose which process to debug when a fork() happens
4668 HP has donated a curses-based terminal user interface (TUI). To get
4669 it, build with --enable-tui. Although this can be enabled for any
4670 configuration, at present it only works for native HP debugging.
4672 * GDB remote protocol additions
4674 A new protocol packet 'X' that writes binary data is now available.
4675 Default behavior is to try 'X', then drop back to 'M' if the stub
4676 fails to respond. The settable variable `remotebinarydownload'
4677 allows explicit control over the use of 'X'.
4679 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4680 full 64-bit address. The command
4682 set remoteaddresssize 32
4684 can be used to revert to the old behaviour. For existing remote stubs
4685 the change should not be noticed, as the additional address information
4688 In order to assist in debugging stubs, you may use the maintenance
4689 command `packet' to send any text string to the stub. For instance,
4691 maint packet heythere
4693 sends the packet "$heythere#<checksum>". Note that it is very easy to
4694 disrupt a debugging session by sending the wrong packet at the wrong
4697 The compare-sections command allows you to compare section data on the
4698 target to what is in the executable file without uploading or
4699 downloading, by comparing CRC checksums.
4701 * Tracing can collect general expressions
4703 You may now collect general expressions at tracepoints. This requires
4704 further additions to the target-side stub; see tracepoint.c and
4705 doc/agentexpr.texi for further details.
4707 * mask-address variable for Mips
4709 For Mips targets, you may control the zeroing of the upper 32 bits of
4710 a 64-bit address by entering `set mask-address on'. This is mainly
4711 of interest to users of embedded R4xxx and R5xxx processors.
4713 * Higher serial baud rates
4715 GDB's serial code now allows you to specify baud rates 57600, 115200,
4716 230400, and 460800 baud. (Note that your host system may not be able
4717 to achieve all of these rates.)
4721 The i960 configuration now includes an initial implementation of a
4722 builtin simulator, contributed by Jim Wilson.
4725 *** Changes in GDB-4.17:
4727 * New native configurations
4729 Alpha GNU/Linux alpha*-*-linux*
4730 Unixware 2.x i[3456]86-unixware2*
4731 Irix 6.x mips*-sgi-irix6*
4732 PowerPC GNU/Linux powerpc-*-linux*
4733 PowerPC Solaris powerpcle-*-solaris*
4734 Sparc GNU/Linux sparc-*-linux*
4735 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4739 Argonaut Risc Chip (ARC) arc-*-*
4740 Hitachi H8/300S h8300*-*-*
4741 Matsushita MN10200 w/simulator mn10200-*-*
4742 Matsushita MN10300 w/simulator mn10300-*-*
4743 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4744 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4745 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4746 Mitsubishi D10V w/simulator d10v-*-*
4747 Mitsubishi M32R/D w/simulator m32r-*-elf*
4748 Tsqware Sparclet sparclet-*-*
4749 NEC V850 w/simulator v850-*-*
4751 * New debugging protocols
4753 ARM with RDI protocol arm*-*-*
4754 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4755 DDB and LSI variants of PMON protocol mips*-*-*
4756 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4757 PowerPC with SDS protocol powerpc{,le}-*-eabi
4758 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4762 All configurations can now understand and use the DWARF 2 debugging
4763 format. The choice is automatic, if the symbol file contains DWARF 2
4768 GDB now includes basic Java language support. This support is
4769 only useful with Java compilers that produce native machine code.
4771 * solib-absolute-prefix and solib-search-path
4773 For SunOS and SVR4 shared libraries, you may now set the prefix for
4774 loading absolute shared library symbol files, and the search path for
4775 locating non-absolute shared library symbol files.
4777 * Live range splitting
4779 GDB can now effectively debug code for which GCC has performed live
4780 range splitting as part of its optimization. See gdb/doc/LRS for
4781 more details on the expected format of the stabs information.
4785 GDB's support for the GNU Hurd, including thread debugging, has been
4786 updated to work with current versions of the Hurd.
4790 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4791 instruction set. ARM GDB automatically detects when Thumb
4792 instructions are in use, and adjusts disassembly and backtracing
4797 GDB's MIPS target configurations now handle the MIP16 16-bit
4802 GDB now includes support for overlays; if an executable has been
4803 linked such that multiple sections are based at the same address, GDB
4804 will decide which section to use for symbolic info. You can choose to
4805 control the decision manually, using overlay commands, or implement
4806 additional target-side support and use "overlay load-target" to bring
4807 in the overlay mapping. Do "help overlay" for more detail.
4811 The command "info symbol <address>" displays information about
4812 the symbol at the specified address.
4816 The standard remote protocol now includes an extension that allows
4817 asynchronous collection and display of trace data. This requires
4818 extensive support in the target-side debugging stub. Tracing mode
4819 includes a new interaction mode in GDB and new commands: see the
4820 file tracepoint.c for more details.
4824 Configurations for embedded MIPS now include a simulator contributed
4825 by Cygnus Solutions. The simulator supports the instruction sets
4826 of most MIPS variants.
4830 Sparc configurations may now include the ERC32 simulator contributed
4831 by the European Space Agency. The simulator is not built into
4832 Sparc targets by default; configure with --enable-sim to include it.
4836 For target configurations that may include multiple variants of a
4837 basic architecture (such as MIPS and SH), you may now set the
4838 architecture explicitly. "set arch" sets, "info arch" lists
4839 the possible architectures.
4841 *** Changes in GDB-4.16:
4843 * New native configurations
4845 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4846 M68K NetBSD m68k-*-netbsd*
4847 PowerPC AIX 4.x powerpc-*-aix*
4848 PowerPC MacOS powerpc-*-macos*
4849 PowerPC Windows NT powerpcle-*-cygwin32
4850 RS/6000 AIX 4.x rs6000-*-aix4*
4854 ARM with RDP protocol arm-*-*
4855 I960 with MON960 i960-*-coff
4856 MIPS VxWorks mips*-*-vxworks*
4857 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4858 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4860 Matra Sparclet sparclet-*-*
4864 The powerpc-eabi configuration now includes the PSIM simulator,
4865 contributed by Andrew Cagney, with assistance from Mike Meissner.
4866 PSIM is a very elaborate model of the PowerPC, including not only
4867 basic instruction set execution, but also details of execution unit
4868 performance and I/O hardware. See sim/ppc/README for more details.
4872 GDB now works with Solaris 2.5.
4874 * Windows 95/NT native
4876 GDB will now work as a native debugger on Windows 95 and Windows NT.
4877 To build it from source, you must use the "gnu-win32" environment,
4878 which uses a DLL to emulate enough of Unix to run the GNU tools.
4879 Further information, binaries, and sources are available at
4880 ftp.cygnus.com, under pub/gnu-win32.
4882 * dont-repeat command
4884 If a user-defined command includes the command `dont-repeat', then the
4885 command will not be repeated if the user just types return. This is
4886 useful if the command is time-consuming to run, so that accidental
4887 extra keystrokes don't run the same command many times.
4889 * Send break instead of ^C
4891 The standard remote protocol now includes an option to send a break
4892 rather than a ^C to the target in order to interrupt it. By default,
4893 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4895 * Remote protocol timeout
4897 The standard remote protocol includes a new variable `remotetimeout'
4898 that allows you to set the number of seconds before GDB gives up trying
4899 to read from the target. The default value is 2.
4901 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4903 By default GDB will automatically keep track of objects as they are
4904 loaded and unloaded by the dynamic linker. By using the command `set
4905 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4906 when shared library events occur, thus allowing you to set breakpoints
4907 in shared libraries which are explicitly loaded by the inferior.
4909 Note this feature does not work on hpux8. On hpux9 you must link
4910 /usr/lib/end.o into your program. This feature should work
4911 automatically on hpux10.
4913 * Irix 5.x hardware watchpoint support
4915 Irix 5 configurations now support the use of hardware watchpoints.
4917 * Mips protocol "SYN garbage limit"
4919 When debugging a Mips target using the `target mips' protocol, you
4920 may set the number of characters that GDB will ignore by setting
4921 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4922 every character. The default value is 1050.
4924 * Recording and replaying remote debug sessions
4926 If you set `remotelogfile' to the name of a file, gdb will write to it
4927 a recording of a remote debug session. This recording may then be
4928 replayed back to gdb using "gdbreplay". See gdbserver/README for
4929 details. This is useful when you have a problem with GDB while doing
4930 remote debugging; you can make a recording of the session and send it
4931 to someone else, who can then recreate the problem.
4933 * Speedups for remote debugging
4935 GDB includes speedups for downloading and stepping MIPS systems using
4936 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4937 and more efficient S-record downloading.
4939 * Memory use reductions and statistics collection
4941 GDB now uses less memory and reports statistics about memory usage.
4942 Try the `maint print statistics' command, for example.
4944 *** Changes in GDB-4.15:
4946 * Psymtabs for XCOFF
4948 The symbol reader for AIX GDB now uses partial symbol tables. This
4949 can greatly improve startup time, especially for large executables.
4951 * Remote targets use caching
4953 Remote targets now use a data cache to speed up communication with the
4954 remote side. The data cache could lead to incorrect results because
4955 it doesn't know about volatile variables, thus making it impossible to
4956 debug targets which use memory mapped I/O devices. `set remotecache
4957 off' turns the the data cache off.
4959 * Remote targets may have threads
4961 The standard remote protocol now includes support for multiple threads
4962 in the target system, using new protocol commands 'H' and 'T'. See
4963 gdb/remote.c for details.
4967 If GDB is configured with `--enable-netrom', then it will include
4968 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4969 acts as though it is a bank of ROM on the target board, but you can
4970 write into it over the network. GDB's support consists only of
4971 support for fast loading into the emulated ROM; to debug, you must use
4972 another protocol, such as standard remote protocol. The usual
4973 sequence is something like
4975 target nrom <netrom-hostname>
4977 target remote <netrom-hostname>:1235
4981 GDB now includes support for the Apple Macintosh, as a host only. It
4982 may be run as either an MPW tool or as a standalone application, and
4983 it can debug through the serial port. All the usual GDB commands are
4984 available, but to the target command, you must supply "serial" as the
4985 device type instead of "/dev/ttyXX". See mpw-README in the main
4986 directory for more information on how to build. The MPW configuration
4987 scripts */mpw-config.in support only a few targets, and only the
4988 mips-idt-ecoff target has been tested.
4992 GDB configuration now uses autoconf. This is not user-visible,
4993 but does simplify configuration and building.
4997 GDB now supports hpux10.
4999 *** Changes in GDB-4.14:
5001 * New native configurations
5003 x86 FreeBSD i[345]86-*-freebsd
5004 x86 NetBSD i[345]86-*-netbsd
5005 NS32k NetBSD ns32k-*-netbsd
5006 Sparc NetBSD sparc-*-netbsd
5010 A29K VxWorks a29k-*-vxworks
5011 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5012 CPU32 EST-300 emulator m68*-*-est*
5013 PowerPC ELF powerpc-*-elf
5016 * Alpha OSF/1 support for procfs
5018 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5019 possible to attach to running processes. As the mounting of the /proc
5020 filesystem is optional on the Alpha, GDB automatically determines
5021 the availability of /proc during startup. This can lead to problems
5022 if /proc is unmounted after GDB has been started.
5024 * Arguments to user-defined commands
5026 User commands may accept up to 10 arguments separated by whitespace.
5027 Arguments are accessed within the user command via $arg0..$arg9. A
5030 print $arg0 + $arg1 + $arg2
5032 To execute the command use:
5035 Defines the command "adder" which prints the sum of its three arguments.
5036 Note the arguments are text substitutions, so they may reference variables,
5037 use complex expressions, or even perform inferior function calls.
5039 * New `if' and `while' commands
5041 This makes it possible to write more sophisticated user-defined
5042 commands. Both commands take a single argument, which is the
5043 expression to evaluate, and must be followed by the commands to
5044 execute, one per line, if the expression is nonzero, the list being
5045 terminated by the word `end'. The `if' command list may include an
5046 `else' word, which causes the following commands to be executed only
5047 if the expression is zero.
5049 * Fortran source language mode
5051 GDB now includes partial support for Fortran 77. It will recognize
5052 Fortran programs and can evaluate a subset of Fortran expressions, but
5053 variables and functions may not be handled correctly. GDB will work
5054 with G77, but does not yet know much about symbols emitted by other
5057 * Better HPUX support
5059 Most debugging facilities now work on dynamic executables for HPPAs
5060 running hpux9 or later. You can attach to running dynamically linked
5061 processes, but by default the dynamic libraries will be read-only, so
5062 for instance you won't be able to put breakpoints in them. To change
5063 that behavior do the following before running the program:
5069 This will cause the libraries to be mapped private and read-write.
5070 To revert to the normal behavior, do this:
5076 You cannot set breakpoints or examine data in the library until after
5077 the library is loaded if the function/data symbols do not have
5080 GDB can now also read debug symbols produced by the HP C compiler on
5081 HPPAs (sorry, no C++, Fortran or 68k support).
5083 * Target byte order now dynamically selectable
5085 You can choose which byte order to use with a target system, via the
5086 commands "set endian big" and "set endian little", and you can see the
5087 current setting by using "show endian". You can also give the command
5088 "set endian auto", in which case GDB will use the byte order
5089 associated with the executable. Currently, only embedded MIPS
5090 configurations support dynamic selection of target byte order.
5092 * New DOS host serial code
5094 This version uses DPMI interrupts to handle buffered I/O, so you
5095 no longer need to run asynctsr when debugging boards connected to
5098 *** Changes in GDB-4.13:
5100 * New "complete" command
5102 This lists all the possible completions for the rest of the line, if it
5103 were to be given as a command itself. This is intended for use by emacs.
5105 * Trailing space optional in prompt
5107 "set prompt" no longer adds a space for you after the prompt you set. This
5108 allows you to set a prompt which ends in a space or one that does not.
5110 * Breakpoint hit counts
5112 "info break" now displays a count of the number of times the breakpoint
5113 has been hit. This is especially useful in conjunction with "ignore"; you
5114 can ignore a large number of breakpoint hits, look at the breakpoint info
5115 to see how many times the breakpoint was hit, then run again, ignoring one
5116 less than that number, and this will get you quickly to the last hit of
5119 * Ability to stop printing at NULL character
5121 "set print null-stop" will cause GDB to stop printing the characters of
5122 an array when the first NULL is encountered. This is useful when large
5123 arrays actually contain only short strings.
5125 * Shared library breakpoints
5127 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5128 breakpoints in shared libraries before the executable is run.
5130 * Hardware watchpoints
5132 There is a new hardware breakpoint for the watch command for sparclite
5133 targets. See gdb/sparclite/hw_breakpoint.note.
5135 Hardware watchpoints are also now supported under GNU/Linux.
5139 Annotations have been added. These are for use with graphical interfaces,
5140 and are still experimental. Currently only gdba.el uses these.
5142 * Improved Irix 5 support
5144 GDB now works properly with Irix 5.2.
5146 * Improved HPPA support
5148 GDB now works properly with the latest GCC and GAS.
5150 * New native configurations
5152 Sequent PTX4 i[34]86-sequent-ptx4
5153 HPPA running OSF/1 hppa*-*-osf*
5154 Atari TT running SVR4 m68*-*-sysv4*
5155 RS/6000 LynxOS rs6000-*-lynxos*
5159 OS/9000 i[34]86-*-os9k
5160 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5163 * Hitachi SH7000 and E7000-PC ICE support
5165 There is now support for communicating with the Hitachi E7000-PC ICE.
5166 This is available automatically when GDB is configured for the SH.
5170 As usual, a variety of small fixes and improvements, both generic
5171 and configuration-specific. See the ChangeLog for more detail.
5173 *** Changes in GDB-4.12:
5175 * Irix 5 is now supported
5179 GDB-4.12 on the HPPA has a number of changes which make it unable
5180 to debug the output from the currently released versions of GCC and
5181 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5182 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5183 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5186 *** Changes in GDB-4.11:
5188 * User visible changes:
5192 The "set remotedebug" option is now consistent between the mips remote
5193 target, remote targets using the gdb-specific protocol, UDI (AMD's
5194 debug protocol for the 29k) and the 88k bug monitor. It is now an
5195 integer specifying a debug level (normally 0 or 1, but 2 means more
5196 debugging info for the mips target).
5198 * DEC Alpha native support
5200 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5201 debug info, but GDB works fairly well with the DEC compiler and should
5202 work with a future GCC release. See the README file for a few
5203 Alpha-specific notes.
5205 * Preliminary thread implementation
5207 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5209 * LynxOS native and target support for 386
5211 This release has been hosted on LynxOS 2.2, and also can be configured
5212 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5215 * Improvements in C++ mangling/demangling.
5217 This release has much better g++ debugging, specifically in name
5218 mangling/demangling, virtual function calls, print virtual table,
5219 call methods, ...etc.
5221 *** Changes in GDB-4.10:
5223 * User visible changes:
5225 Remote debugging using the GDB-specific (`target remote') protocol now
5226 supports the `load' command. This is only useful if you have some
5227 other way of getting the stub to the target system, and you can put it
5228 somewhere in memory where it won't get clobbered by the download.
5230 Filename completion now works.
5232 When run under emacs mode, the "info line" command now causes the
5233 arrow to point to the line specified. Also, "info line" prints
5234 addresses in symbolic form (as well as hex).
5236 All vxworks based targets now support a user settable option, called
5237 vxworks-timeout. This option represents the number of seconds gdb
5238 should wait for responses to rpc's. You might want to use this if
5239 your vxworks target is, perhaps, a slow software simulator or happens
5240 to be on the far side of a thin network line.
5244 This release contains support for using a DEC alpha as a GDB host for
5245 cross debugging. Native alpha debugging is not supported yet.
5248 *** Changes in GDB-4.9:
5252 This is the first GDB release which is accompanied by a matching testsuite.
5253 The testsuite requires installation of dejagnu, which should be available
5254 via ftp from most sites that carry GNU software.
5258 'Cfront' style demangling has had its name changed to 'ARM' style, to
5259 emphasize that it was written from the specifications in the C++ Annotated
5260 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5261 disclaimers, it still generated too much confusion with users attempting to
5262 use gdb with AT&T cfront.
5266 GDB now uses a standard remote interface to a simulator library.
5267 So far, the library contains simulators for the Zilog Z8001/2, the
5268 Hitachi H8/300, H8/500 and Super-H.
5270 * New targets supported
5272 H8/300 simulator h8300-hitachi-hms or h8300hms
5273 H8/500 simulator h8500-hitachi-hms or h8500hms
5274 SH simulator sh-hitachi-hms or sh
5275 Z8000 simulator z8k-zilog-none or z8ksim
5276 IDT MIPS board over serial line mips-idt-ecoff
5278 Cross-debugging to GO32 targets is supported. It requires a custom
5279 version of the i386-stub.c module which is integrated with the
5280 GO32 memory extender.
5282 * New remote protocols
5284 MIPS remote debugging protocol.
5286 * New source languages supported
5288 This version includes preliminary support for Chill, a Pascal like language
5289 used by telecommunications companies. Chill support is also being integrated
5290 into the GNU compiler, but we don't know when it will be publically available.
5293 *** Changes in GDB-4.8:
5295 * HP Precision Architecture supported
5297 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5298 version of this support was available as a set of patches from the
5299 University of Utah. GDB does not support debugging of programs
5300 compiled with the HP compiler, because HP will not document their file
5301 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5302 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5304 Many problems in the preliminary version have been fixed.
5306 * Faster and better demangling
5308 We have improved template demangling and fixed numerous bugs in the GNU style
5309 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5310 character types (wchar_t) are now supported. Demangling of each symbol is now
5311 only done once, and is cached when the symbol table for a file is read in.
5312 This results in a small increase in memory usage for C programs, a moderate
5313 increase in memory usage for C++ programs, and a fantastic speedup in
5316 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5317 from the specifications in the Annotated Reference Manual, which AT&T's
5318 compiler does not actually implement.
5320 * G++ multiple inheritance compiler problem
5322 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5323 inheritance lattices was reworked to properly discover ambiguities. We
5324 recently found an example which causes this new algorithm to fail in a
5325 very subtle way, producing bad debug information for those classes.
5326 The file 'gcc.patch' (in this directory) can be applied to gcc to
5327 circumvent the problem. A future GCC release will contain a complete
5330 The previous G++ debug info problem (mentioned below for the gdb-4.7
5331 release) is fixed in gcc version 2.3.2.
5333 * Improved configure script
5335 The `configure' script will now attempt to guess your system type if
5336 you don't supply a host system type. The old scheme of supplying a
5337 host system triplet is preferable over using this. All the magic is
5338 done in the new `config.guess' script. Examine it for details.
5340 We have also brought our configure script much more in line with the FSF's
5341 version. It now supports the --with-xxx options. In particular,
5342 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5343 The resulting GDB will not be able to read arbitrary object file formats --
5344 only the format ``expected'' to be used on the configured target system.
5345 We hope to make this the default in a future release.
5347 * Documentation improvements
5349 There's new internal documentation on how to modify GDB, and how to
5350 produce clean changes to the code. We implore people to read it
5351 before submitting changes.
5353 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5354 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5355 `info' files are also provided. To build `info' files from scratch,
5356 you will need the latest `makeinfo' release, which will be available in
5357 a future texinfo-X.Y release.
5359 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5360 We're not sure exactly which versions have this problem, but it has
5361 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5362 or better. If that isn't possible, there is a patch in
5363 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5364 around this problem.
5368 GDB now supports array constants that can be used in expressions typed in by
5369 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5370 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5373 The new directory `gdb/sparclite' contains a program that demonstrates
5374 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5376 * New native hosts supported
5378 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5379 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5381 * New targets supported
5383 AMD 29k family via UDI a29k-amd-udi or udi29k
5385 * New file formats supported
5387 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5388 HPUX core files, and SCO 3.2v2 core files.
5392 Attaching to processes now works again; thanks for the many bug reports.
5394 We have also stomped on a bunch of core dumps caused by
5395 printf_filtered("%s") problems.
5397 We eliminated a copyright problem on the rpc and ptrace header files
5398 for VxWorks, which was discovered at the last minute during the 4.7
5399 release. You should now be able to build a VxWorks GDB.
5401 You can now interrupt gdb while an attached process is running. This
5402 will cause the attached process to stop, and give control back to GDB.
5404 We fixed problems caused by using too many file descriptors
5405 for reading symbols from object files and libraries. This was
5406 especially a problem for programs that used many (~100) shared
5409 The `step' command now only enters a subroutine if there is line number
5410 information for the subroutine. Otherwise it acts like the `next'
5411 command. Previously, `step' would enter subroutines if there was
5412 any debugging information about the routine. This avoids problems
5413 when using `cc -g1' on MIPS machines.
5415 * Internal improvements
5417 GDB's internal interfaces have been improved to make it easier to support
5418 debugging of multiple languages in the future.
5420 GDB now uses a common structure for symbol information internally.
5421 Minimal symbols (derived from linkage symbols in object files), partial
5422 symbols (from a quick scan of debug information), and full symbols
5423 contain a common subset of information, making it easier to write
5424 shared code that handles any of them.
5426 * New command line options
5428 We now accept --silent as an alias for --quiet.
5432 The memory-mapped-malloc library is now licensed under the GNU Library
5433 General Public License.
5435 *** Changes in GDB-4.7:
5437 * Host/native/target split
5439 GDB has had some major internal surgery to untangle the support for
5440 hosts and remote targets. Now, when you configure GDB for a remote
5441 target, it will no longer load in all of the support for debugging
5442 local programs on the host. When fully completed and tested, this will
5443 ensure that arbitrary host/target combinations are possible.
5445 The primary conceptual shift is to separate the non-portable code in
5446 GDB into three categories. Host specific code is required any time GDB
5447 is compiled on that host, regardless of the target. Target specific
5448 code relates to the peculiarities of the target, but can be compiled on
5449 any host. Native specific code is everything else: it can only be
5450 built when the host and target are the same system. Child process
5451 handling and core file support are two common `native' examples.
5453 GDB's use of /proc for controlling Unix child processes is now cleaner.
5454 It has been split out into a single module under the `target_ops' vector,
5455 plus two native-dependent functions for each system that uses /proc.
5457 * New hosts supported
5459 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5460 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5461 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5463 * New targets supported
5465 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5466 68030 and CPU32 m68030-*-*, m68332-*-*
5468 * New native hosts supported
5470 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5471 (386bsd is not well tested yet)
5472 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5474 * New file formats supported
5476 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5477 supports reading of `a.out.adobe' object files, which are an a.out
5478 format extended with minimal information about multiple sections.
5482 `show copying' is the same as the old `info copying'.
5483 `show warranty' is the same as `info warrantee'.
5484 These were renamed for consistency. The old commands continue to work.
5486 `info handle' is a new alias for `info signals'.
5488 You can now define pre-command hooks, which attach arbitrary command
5489 scripts to any command. The commands in the hook will be executed
5490 prior to the user's command. You can also create a hook which will be
5491 executed whenever the program stops. See gdb.texinfo.
5495 We now deal with Cfront style name mangling, and can even extract type
5496 info from mangled symbols. GDB can automatically figure out which
5497 symbol mangling style your C++ compiler uses.
5499 Calling of methods and virtual functions has been improved as well.
5503 The crash that occured when debugging Sun Ansi-C compiled binaries is
5504 fixed. This was due to mishandling of the extra N_SO stabs output
5507 We also finally got Ultrix 4.2 running in house, and fixed core file
5508 support, with help from a dozen people on the net.
5510 John M. Farrell discovered that the reason that single-stepping was so
5511 slow on all of the Mips based platforms (primarily SGI and DEC) was
5512 that we were trying to demangle and lookup a symbol used for internal
5513 purposes on every instruction that was being stepped through. Changing
5514 the name of that symbol so that it couldn't be mistaken for a C++
5515 mangled symbol sped things up a great deal.
5517 Rich Pixley sped up symbol lookups in general by getting much smarter
5518 about when C++ symbol mangling is necessary. This should make symbol
5519 completion (TAB on the command line) much faster. It's not as fast as
5520 we'd like, but it's significantly faster than gdb-4.6.
5524 A new user controllable variable 'call_scratch_address' can
5525 specify the location of a scratch area to be used when GDB
5526 calls a function in the target. This is necessary because the
5527 usual method of putting the scratch area on the stack does not work
5528 in systems that have separate instruction and data spaces.
5530 We integrated changes to support the 29k UDI (Universal Debugger
5531 Interface), but discovered at the last minute that we didn't have all
5532 of the appropriate copyright paperwork. We are working with AMD to
5533 resolve this, and hope to have it available soon.
5537 We have sped up the remote serial line protocol, especially for targets
5538 with lots of registers. It now supports a new `expedited status' ('T')
5539 message which can be used in place of the existing 'S' status message.
5540 This allows the remote stub to send only the registers that GDB
5541 needs to make a quick decision about single-stepping or conditional
5542 breakpoints, eliminating the need to fetch the entire register set for
5543 each instruction being stepped through.
5545 The GDB remote serial protocol now implements a write-through cache for
5546 registers, only re-reading the registers if the target has run.
5548 There is also a new remote serial stub for SPARC processors. You can
5549 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5550 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5551 processor with a serial port.
5555 Configure.in files have become much easier to read and modify. A new
5556 `table driven' format makes it more obvious what configurations are
5557 supported, and what files each one uses.
5561 There is a new opcodes library which will eventually contain all of the
5562 disassembly routines and opcode tables. At present, it only contains
5563 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5564 disassembler (binutils/objdump) to share these routines.
5566 The libiberty library is now copylefted under the GNU Library General
5567 Public License. This allows more liberal use, and was done so libg++
5568 can use it. This makes no difference to GDB, since the Library License
5569 grants all the rights from the General Public License.
5573 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5574 reference to the stabs symbol info used by the debugger. It is (as far
5575 as we know) the only published document on this fascinating topic. We
5576 encourage you to read it, compare it to the stabs information on your
5577 system, and send improvements on the document in general (to
5578 bug-gdb@prep.ai.mit.edu).
5580 And, of course, many bugs have been fixed.
5583 *** Changes in GDB-4.6:
5585 * Better support for C++ function names
5587 GDB now accepts as input the "demangled form" of C++ overloaded function
5588 names and member function names, and can do command completion on such names
5589 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5590 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5591 Make use of command completion, it is your friend.
5593 GDB also now accepts a variety of C++ mangled symbol formats. They are
5594 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5595 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5596 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5597 for the list of formats.
5599 * G++ symbol mangling problem
5601 Recent versions of gcc have a bug in how they emit debugging information for
5602 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5603 directory) can be applied to gcc to fix the problem. Alternatively, if you
5604 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5605 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5606 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5609 * New 'maintenance' command
5611 All of the commands related to hacking GDB internals have been moved out of
5612 the main command set, and now live behind the 'maintenance' command. This
5613 can also be abbreviated as 'mt'. The following changes were made:
5615 dump-me -> maintenance dump-me
5616 info all-breakpoints -> maintenance info breakpoints
5617 printmsyms -> maintenance print msyms
5618 printobjfiles -> maintenance print objfiles
5619 printpsyms -> maintenance print psymbols
5620 printsyms -> maintenance print symbols
5622 The following commands are new:
5624 maintenance demangle Call internal GDB demangler routine to
5625 demangle a C++ link name and prints the result.
5626 maintenance print type Print a type chain for a given symbol
5628 * Change to .gdbinit file processing
5630 We now read the $HOME/.gdbinit file before processing the argv arguments
5631 (e.g. reading symbol files or core files). This allows global parameters to
5632 be set, which will apply during the symbol reading. The ./.gdbinit is still
5633 read after argv processing.
5635 * New hosts supported
5637 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5639 GNU/Linux support i386-unknown-linux or linux
5641 We are also including code to support the HP/PA running BSD and HPUX. This
5642 is almost guaranteed not to work, as we didn't have time to test or build it
5643 for this release. We are including it so that the more adventurous (or
5644 masochistic) of you can play with it. We also had major problems with the
5645 fact that the compiler that we got from HP doesn't support the -g option.
5648 * New targets supported
5650 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5652 * More smarts about finding #include files
5654 GDB now remembers the compilation directory for all include files, and for
5655 all files from which C is generated (like yacc and lex sources). This
5656 greatly improves GDB's ability to find yacc/lex sources, and include files,
5657 especially if you are debugging your program from a directory different from
5658 the one that contains your sources.
5660 We also fixed a bug which caused difficulty with listing and setting
5661 breakpoints in include files which contain C code. (In the past, you had to
5662 try twice in order to list an include file that you hadn't looked at before.)
5664 * Interesting infernals change
5666 GDB now deals with arbitrary numbers of sections, where the symbols for each
5667 section must be relocated relative to that section's landing place in the
5668 target's address space. This work was needed to support ELF with embedded
5669 stabs used by Solaris-2.0.
5671 * Bug fixes (of course!)
5673 There have been loads of fixes for the following things:
5674 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5675 i960, stabs, DOS(GO32), procfs, etc...
5677 See the ChangeLog for details.
5679 *** Changes in GDB-4.5:
5681 * New machines supported (host and target)
5683 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5685 SGI Irix-4.x mips-sgi-irix4 or iris4
5687 * New malloc package
5689 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5690 Mmalloc is capable of handling mutiple heaps of memory. It is also
5691 capable of saving a heap to a file, and then mapping it back in later.
5692 This can be used to greatly speedup the startup of GDB by using a
5693 pre-parsed symbol table which lives in a mmalloc managed heap. For
5694 more details, please read mmalloc/mmalloc.texi.
5698 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5699 'help info proc' for details.
5701 * MIPS ecoff symbol table format
5703 The code that reads MIPS symbol table format is now supported on all hosts.
5704 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5707 * File name changes for MS-DOS
5709 Many files in the config directories have been renamed to make it easier to
5710 support GDB on MS-DOSe systems (which have very restrictive file name
5711 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5712 environment) is close to working but has some remaining problems. Note
5713 that debugging of DOS programs is not supported, due to limitations
5714 in the ``operating system'', but it can be used to host cross-debugging.
5716 * Cross byte order fixes
5718 Many fixes have been made to support cross debugging of Sparc and MIPS
5719 targets from hosts whose byte order differs.
5721 * New -mapped and -readnow options
5723 If memory-mapped files are available on your system through the 'mmap'
5724 system call, you can use the -mapped option on the `file' or
5725 `symbol-file' commands to cause GDB to write the symbols from your
5726 program into a reusable file. If the program you are debugging is
5727 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5728 Future GDB debugging sessions will notice the presence of this file,
5729 and will quickly map in symbol information from it, rather than reading
5730 the symbol table from the executable program. Using the '-mapped'
5731 option in a GDB `file' or `symbol-file' command has the same effect as
5732 starting GDB with the '-mapped' command-line option.
5734 You can cause GDB to read the entire symbol table immediately by using
5735 the '-readnow' option with any of the commands that load symbol table
5736 information (or on the GDB command line). This makes the command
5737 slower, but makes future operations faster.
5739 The -mapped and -readnow options are typically combined in order to
5740 build a `fred.syms' file that contains complete symbol information.
5741 A simple GDB invocation to do nothing but build a `.syms' file for future
5744 gdb -batch -nx -mapped -readnow programname
5746 The `.syms' file is specific to the host machine on which GDB is run.
5747 It holds an exact image of GDB's internal symbol table. It cannot be
5748 shared across multiple host platforms.
5750 * longjmp() handling
5752 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5753 siglongjmp() without losing control. This feature has not yet been ported to
5754 all systems. It currently works on many 386 platforms, all MIPS-based
5755 platforms (SGI, DECstation, etc), and Sun3/4.
5759 Preliminary work has been put in to support the new Solaris OS from Sun. At
5760 this time, it can control and debug processes, but it is not capable of
5765 As always, many many bug fixes. The major areas were with g++, and mipsread.
5766 People using the MIPS-based platforms should experience fewer mysterious
5767 crashes and trashed symbol tables.
5769 *** Changes in GDB-4.4:
5771 * New machines supported (host and target)
5773 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5775 BSD Reno on Vax vax-dec-bsd
5776 Ultrix on Vax vax-dec-ultrix
5778 * New machines supported (target)
5780 AMD 29000 embedded, using EBMON a29k-none-none
5784 GDB continues to improve its handling of C++. `References' work better.
5785 The demangler has also been improved, and now deals with symbols mangled as
5786 per the Annotated C++ Reference Guide.
5788 GDB also now handles `stabs' symbol information embedded in MIPS
5789 `ecoff' symbol tables. Since the ecoff format was not easily
5790 extensible to handle new languages such as C++, this appeared to be a
5791 good way to put C++ debugging info into MIPS binaries. This option
5792 will be supported in the GNU C compiler, version 2, when it is
5795 * New features for SVR4
5797 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5798 shared libraries. Debugging dynamically linked programs should present
5799 only minor differences from debugging statically linked programs.
5801 The `info proc' command will print out information about any process
5802 on an SVR4 system (including the one you are debugging). At the moment,
5803 it prints the address mappings of the process.
5805 If you bring up GDB on another SVR4 system, please send mail to
5806 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5808 * Better dynamic linking support in SunOS
5810 Reading symbols from shared libraries which contain debugging symbols
5811 now works properly. However, there remain issues such as automatic
5812 skipping of `transfer vector' code during function calls, which
5813 make it harder to debug code in a shared library, than to debug the
5814 same code linked statically.
5818 GDB is now using the latest `getopt' routines from the FSF. This
5819 version accepts the -- prefix for options with long names. GDB will
5820 continue to accept the old forms (-option and +option) as well.
5821 Various single letter abbreviations for options have been explicity
5822 added to the option table so that they won't get overshadowed in the
5823 future by other options that begin with the same letter.
5827 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5828 Many assorted bugs have been handled. Many more remain to be handled.
5829 See the various ChangeLog files (primarily in gdb and bfd) for details.
5832 *** Changes in GDB-4.3:
5834 * New machines supported (host and target)
5836 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5837 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5838 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5840 * Almost SCO Unix support
5842 We had hoped to support:
5843 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5844 (except for core file support), but we discovered very late in the release
5845 that it has problems with process groups that render gdb unusable. Sorry
5846 about that. I encourage people to fix it and post the fixes.
5848 * Preliminary ELF and DWARF support
5850 GDB can read ELF object files on System V Release 4, and can handle
5851 debugging records for C, in DWARF format, in ELF files. This support
5852 is preliminary. If you bring up GDB on another SVR4 system, please
5853 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5858 GDB now uses the latest `readline' library. One user-visible change
5859 is that two tabs will list possible command completions, which previously
5860 required typing M-? (meta-question mark, or ESC ?).
5864 The `stepi' bug that many of you noticed has been squashed.
5865 Many bugs in C++ have been handled. Many more remain to be handled.
5866 See the various ChangeLog files (primarily in gdb and bfd) for details.
5868 * State of the MIPS world (in case you wondered):
5870 GDB can understand the symbol tables emitted by the compilers
5871 supplied by most vendors of MIPS-based machines, including DEC. These
5872 symbol tables are in a format that essentially nobody else uses.
5874 Some versions of gcc come with an assembler post-processor called
5875 mips-tfile. This program is required if you want to do source-level
5876 debugging of gcc-compiled programs. I believe FSF does not ship
5877 mips-tfile with gcc version 1, but it will eventually come with gcc
5880 Debugging of g++ output remains a problem. g++ version 1.xx does not
5881 really support it at all. (If you're lucky, you should be able to get
5882 line numbers and stack traces to work, but no parameters or local
5883 variables.) With some work it should be possible to improve the
5886 When gcc version 2 is released, you will have somewhat better luck.
5887 However, even then you will get confusing results for inheritance and
5890 We will eventually provide full debugging of g++ output on
5891 DECstations. This will probably involve some kind of stabs-in-ecoff
5892 encapulation, but the details have not been worked out yet.
5895 *** Changes in GDB-4.2:
5897 * Improved configuration
5899 Only one copy of `configure' exists now, and it is not self-modifying.
5900 Porting BFD is simpler.
5904 The `step' and `next' commands now only stop at the first instruction
5905 of a source line. This prevents the multiple stops that used to occur
5906 in switch statements, for-loops, etc. `Step' continues to stop if a
5907 function that has debugging information is called within the line.
5911 Lots of small bugs fixed. More remain.
5913 * New host supported (not target)
5915 Intel 386 PC clone running Mach i386-none-mach
5918 *** Changes in GDB-4.1:
5920 * Multiple source language support
5922 GDB now has internal scaffolding to handle several source languages.
5923 It determines the type of each source file from its filename extension,
5924 and will switch expression parsing and number formatting to match the
5925 language of the function in the currently selected stack frame.
5926 You can also specifically set the language to be used, with
5927 `set language c' or `set language modula-2'.
5931 GDB now has preliminary support for the GNU Modula-2 compiler,
5932 currently under development at the State University of New York at
5933 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5934 continue through the fall of 1991 and into 1992.
5936 Other Modula-2 compilers are currently not supported, and attempting to
5937 debug programs compiled with them will likely result in an error as the
5938 symbol table is read. Feel free to work on it, though!
5940 There are hooks in GDB for strict type checking and range checking,
5941 in the `Modula-2 philosophy', but they do not currently work.
5945 GDB can now write to executable and core files (e.g. patch
5946 a variable's value). You must turn this switch on, specify
5947 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5948 by assigning a new value to a variable. Modifications take
5951 * Automatic SunOS shared library reading
5953 When you run your program, GDB automatically determines where its
5954 shared libraries (if any) have been loaded, and reads their symbols.
5955 The `share' command is no longer needed. This also works when
5956 examining core files.
5960 You can specify the number of lines that the `list' command shows.
5963 * New machines supported (host and target)
5965 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5966 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5967 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5969 * New hosts supported (not targets)
5971 IBM RT/PC: romp-ibm-aix or rtpc
5973 * New targets supported (not hosts)
5975 AMD 29000 embedded with COFF a29k-none-coff
5976 AMD 29000 embedded with a.out a29k-none-aout
5977 Ultracomputer remote kernel debug a29k-nyu-kern
5979 * New remote interfaces
5985 *** Changes in GDB-4.0:
5989 Wide output is wrapped at good places to make the output more readable.
5991 Gdb now supports cross-debugging from a host machine of one type to a
5992 target machine of another type. Communication with the target system
5993 is over serial lines. The ``target'' command handles connecting to the
5994 remote system; the ``load'' command will download a program into the
5995 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5996 also supports debugging of realtime processes running under VxWorks,
5997 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5998 stub on the target system.
6000 New CPUs supported include the AMD 29000 and Intel 960.
6002 GDB now reads object files and symbol tables via a ``binary file''
6003 library, which allows a single copy of GDB to debug programs of multiple
6004 object file types such as a.out and coff.
6006 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6007 refcard.dvi and refcard.ps are available to format it).
6010 * Control-Variable user interface simplified
6012 All variables that control the operation of the debugger can be set
6013 by the ``set'' command, and displayed by the ``show'' command.
6015 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6016 ``Show prompt'' produces the response:
6017 Gdb's prompt is new-gdb=>.
6019 What follows are the NEW set commands. The command ``help set'' will
6020 print a complete list of old and new set commands. ``help set FOO''
6021 will give a longer description of the variable FOO. ``show'' will show
6022 all of the variable descriptions and their current settings.
6024 confirm on/off: Enables warning questions for operations that are
6025 hard to recover from, e.g. rerunning the program while
6026 it is already running. Default is ON.
6028 editing on/off: Enables EMACS style command line editing
6029 of input. Previous lines can be recalled with
6030 control-P, the current line can be edited with control-B,
6031 you can search for commands with control-R, etc.
6034 history filename NAME: NAME is where the gdb command history
6035 will be stored. The default is .gdb_history,
6036 or the value of the environment variable
6039 history size N: The size, in commands, of the command history. The
6040 default is 256, or the value of the environment variable
6043 history save on/off: If this value is set to ON, the history file will
6044 be saved after exiting gdb. If set to OFF, the
6045 file will not be saved. The default is OFF.
6047 history expansion on/off: If this value is set to ON, then csh-like
6048 history expansion will be performed on
6049 command line input. The default is OFF.
6051 radix N: Sets the default radix for input and output. It can be set
6052 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6053 in the current radix, so "set radix 10" is always a no-op.
6055 height N: This integer value is the number of lines on a page. Default
6056 is 24, the current `stty rows'' setting, or the ``li#''
6057 setting from the termcap entry matching the environment
6060 width N: This integer value is the number of characters on a line.
6061 Default is 80, the current `stty cols'' setting, or the ``co#''
6062 setting from the termcap entry matching the environment
6065 Note: ``set screensize'' is obsolete. Use ``set height'' and
6066 ``set width'' instead.
6068 print address on/off: Print memory addresses in various command displays,
6069 such as stack traces and structure values. Gdb looks
6070 more ``symbolic'' if you turn this off; it looks more
6071 ``machine level'' with it on. Default is ON.
6073 print array on/off: Prettyprint arrays. New convenient format! Default
6076 print demangle on/off: Print C++ symbols in "source" form if on,
6079 print asm-demangle on/off: Same, for assembler level printouts
6082 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6085 * Support for Epoch Environment.
6087 The epoch environment is a version of Emacs v18 with windowing. One
6088 new command, ``inspect'', is identical to ``print'', except that if you
6089 are running in the epoch environment, the value is printed in its own
6093 * Support for Shared Libraries
6095 GDB can now debug programs and core files that use SunOS shared libraries.
6096 Symbols from a shared library cannot be referenced
6097 before the shared library has been linked with the program (this
6098 happens after you type ``run'' and before the function main() is entered).
6099 At any time after this linking (including when examining core files
6100 from dynamically linked programs), gdb reads the symbols from each
6101 shared library when you type the ``sharedlibrary'' command.
6102 It can be abbreviated ``share''.
6104 sharedlibrary REGEXP: Load shared object library symbols for files
6105 matching a unix regular expression. No argument
6106 indicates to load symbols for all shared libraries.
6108 info sharedlibrary: Status of loaded shared libraries.
6113 A watchpoint stops execution of a program whenever the value of an
6114 expression changes. Checking for this slows down execution
6115 tremendously whenever you are in the scope of the expression, but is
6116 quite useful for catching tough ``bit-spreader'' or pointer misuse
6117 problems. Some machines such as the 386 have hardware for doing this
6118 more quickly, and future versions of gdb will use this hardware.
6120 watch EXP: Set a watchpoint (breakpoint) for an expression.
6122 info watchpoints: Information about your watchpoints.
6124 delete N: Deletes watchpoint number N (same as breakpoints).
6125 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6126 enable N: Re-enables watchpoint number N (same as breakpoints).
6129 * C++ multiple inheritance
6131 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6134 * C++ exception handling
6136 Gdb now supports limited C++ exception handling. Besides the existing
6137 ability to breakpoint on an exception handler, gdb can breakpoint on
6138 the raising of an exception (before the stack is peeled back to the
6141 catch FOO: If there is a FOO exception handler in the dynamic scope,
6142 set a breakpoint to catch exceptions which may be raised there.
6143 Multiple exceptions (``catch foo bar baz'') may be caught.
6145 info catch: Lists all exceptions which may be caught in the
6146 current stack frame.
6149 * Minor command changes
6151 The command ``call func (arg, arg, ...)'' now acts like the print
6152 command, except it does not print or save a value if the function's result
6153 is void. This is similar to dbx usage.
6155 The ``up'' and ``down'' commands now always print the frame they end up
6156 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6157 frames without printing.
6159 * New directory command
6161 'dir' now adds directories to the FRONT of the source search path.
6162 The path starts off empty. Source files that contain debug information
6163 about the directory in which they were compiled can be found even
6164 with an empty path; Sun CC and GCC include this information. If GDB can't
6165 find your source file in the current directory, type "dir .".
6167 * Configuring GDB for compilation
6169 For normal use, type ``./configure host''. See README or gdb.texinfo
6172 GDB now handles cross debugging. If you are remotely debugging between
6173 two different machines, type ``./configure host -target=targ''.
6174 Host is the machine where GDB will run; targ is the machine
6175 where the program that you are debugging will run.