1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.10
6 * Support for tracepoints on aarch64-linux was added in GDBserver.
8 * The 'record instruction-history' command now indicates speculative execution
9 when using the Intel(R) Processor Trace recording format.
11 * GDB now allows users to specify explicit locations, bypassing
12 the linespec parser. This feature is also available to GDB/MI
17 maint set target-non-stop (on|off|auto)
18 maint show target-non-stop
19 Control whether GDB targets always operate in non-stop mode even if
20 "set non-stop" is "off". The default is "auto", meaning non-stop
21 mode is enabled if supported by the target.
24 maint show bfd-sharing
25 Control the reuse of bfd objects.
27 * The "disassemble" command accepts a new modifier: /s.
28 It prints mixed source+disassembly like /m with two differences:
29 - disassembled instructions are now printed in program order, and
30 - and source for all relevant files is now printed.
31 The "/m" option is now considered deprecated: its "source-centric"
32 output hasn't proved useful in practice.
34 *** Changes in GDB 7.10
36 * Support for process record-replay and reverse debugging on aarch64*-linux*
37 targets has been added. GDB now supports recording of A64 instruction set
38 including advance SIMD instructions.
40 * Support for Sun's version of the "stabs" debug file format has been removed.
42 * GDB now honors the content of the file /proc/PID/coredump_filter
43 (PID is the process ID) on GNU/Linux systems. This file can be used
44 to specify the types of memory mappings that will be included in a
45 corefile. For more information, please refer to the manual page of
46 "core(5)". GDB also has a new command: "set use-coredump-filter
47 on|off". It allows to set whether GDB will read the content of the
48 /proc/PID/coredump_filter file when generating a corefile.
50 * The "info os" command on GNU/Linux can now display information on
52 "info os cpus" Listing of all cpus/cores on the system
54 * GDB has two new commands: "set serial parity odd|even|none" and
55 "show serial parity". These allows to set or show parity for the
58 * The "info source" command now displays the producer string if it was
59 present in the debug info. This typically includes the compiler version
60 and may include things like its command line arguments.
62 * The "info dll", an alias of the "info sharedlibrary" command,
63 is now available on all platforms.
65 * Directory names supplied to the "set sysroot" commands may be
66 prefixed with "target:" to tell GDB to access shared libraries from
67 the target system, be it local or remote. This replaces the prefix
68 "remote:". The default sysroot has been changed from "" to
69 "target:". "remote:" is automatically converted to "target:" for
70 backward compatibility.
72 * The system root specified by "set sysroot" will be prepended to the
73 filename of the main executable (if reported to GDB as absolute by
74 the operating system) when starting processes remotely, and when
75 attaching to already-running local or remote processes.
77 * GDB now supports automatic location and retrieval of executable
78 files from remote targets. Remote debugging can now be initiated
79 using only a "target remote" or "target extended-remote" command
80 (no "set sysroot" or "file" commands are required). See "New remote
83 * The "dump" command now supports verilog hex format.
85 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
87 * On GNU/Linux, GDB and gdbserver are now able to access executable
88 and shared library files without a "set sysroot" command when
89 attaching to processes running in different mount namespaces from
90 the debugger. This makes it possible to attach to processes in
91 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
92 See "New remote packets" below.
94 * The "tui reg" command now provides completion for all of the
95 available register groups, including target specific groups.
97 * The HISTSIZE environment variable is no longer read when determining
98 the size of GDB's command history. GDB now instead reads the dedicated
99 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
100 disables truncation of command history. Non-numeric values of GDBHISTSIZE
105 ** Memory ports can now be unbuffered.
109 ** gdb.Objfile objects have a new attribute "username",
110 which is the name of the objfile as specified by the user,
111 without, for example, resolving symlinks.
112 ** You can now write frame unwinders in Python.
113 ** gdb.Type objects have a new method "optimized_out",
114 returning optimized out gdb.Value instance of this type.
115 ** gdb.Value objects have new methods "reference_value" and
116 "const_value" which return a reference to the value and a
117 "const" version of the value respectively.
121 maint print symbol-cache
122 Print the contents of the symbol cache.
124 maint print symbol-cache-statistics
125 Print statistics of symbol cache usage.
127 maint flush-symbol-cache
128 Flush the contents of the symbol cache.
130 maint set target-non-stop (on|off|auto)
131 maint show target-non-stop
132 Control whether GDB targets always operate in non-stop mode even if
133 "set non-stop" is "off". The default is "auto", meaning non-stop
134 mode is enabled if supported by the target.
138 Start branch trace recording using Branch Trace Store (BTS) format.
141 Evaluate expression by using the compiler and print result.
145 Explicit commands for enabling and disabling tui mode.
148 set mpx bound on i386 and amd64
149 Support for bound table investigation on Intel(R) MPX enabled applications.
153 Start branch trace recording using Intel(R) Processor Trace format.
156 Print information about branch tracing internals.
158 maint btrace packet-history
159 Print the raw branch tracing data.
161 maint btrace clear-packet-history
162 Discard the stored raw branch tracing data.
165 Discard all branch tracing data. It will be fetched and processed
166 anew by the next "record" command.
171 Renamed from "set debug dwarf2-die".
173 Renamed from "show debug dwarf2-die".
176 Renamed from "set debug dwarf2-read".
177 show debug dwarf-read
178 Renamed from "show debug dwarf2-read".
180 maint set dwarf always-disassemble
181 Renamed from "maint set dwarf2 always-disassemble".
182 maint show dwarf always-disassemble
183 Renamed from "maint show dwarf2 always-disassemble".
185 maint set dwarf max-cache-age
186 Renamed from "maint set dwarf2 max-cache-age".
187 maint show dwarf max-cache-age
188 Renamed from "maint show dwarf2 max-cache-age".
191 show debug dwarf-line
192 Control display of debugging info regarding DWARF line processing.
196 Set the maximum number of candidates to be considered during
197 completion. The default value is 200. This limit allows GDB
198 to avoid generating large completion lists, the computation of
199 which can cause the debugger to become temporarily unresponsive.
201 set history remove-duplicates
202 show history remove-duplicates
203 Control the removal of duplicate history entries.
205 maint set symbol-cache-size
206 maint show symbol-cache-size
207 Control the size of the symbol cache.
209 set|show record btrace bts buffer-size
210 Set and show the size of the ring buffer used for branch tracing in
212 The obtained size may differ from the requested size. Use "info
213 record" to see the obtained buffer size.
215 set debug linux-namespaces
216 show debug linux-namespaces
217 Control display of debugging info regarding Linux namespaces.
219 set|show record btrace pt buffer-size
220 Set and show the size of the ring buffer used for branch tracing in
221 Intel(R) Processor Trace format.
222 The obtained size may differ from the requested size. Use "info
223 record" to see the obtained buffer size.
225 maint set|show btrace pt skip-pad
226 Set and show whether PAD packets are skipped when computing the
229 * The command 'thread apply all' can now support new option '-ascending'
230 to call its specified command for all threads in ascending order.
232 * Python/Guile scripting
234 ** GDB now supports auto-loading of Python/Guile scripts contained in the
235 special section named `.debug_gdb_scripts'.
239 qXfer:btrace-conf:read
240 Return the branch trace configuration for the current thread.
242 Qbtrace-conf:bts:size
243 Set the requested ring buffer size for branch tracing in BTS format.
246 Enable Intel(R) Procesor Trace-based branch tracing for the current
247 process. The remote stub reports support for this packet to GDB's
251 Set the requested ring buffer size for branch tracing in Intel(R) Processor
255 Indicates a memory breakpoint instruction was executed, irrespective
256 of whether it was GDB that planted the breakpoint or the breakpoint
257 is hardcoded in the program. This is required for correct non-stop
261 Indicates the target stopped for a hardware breakpoint. This is
262 required for correct non-stop mode operation.
265 Return information about files on the remote system.
268 Return the full absolute name of the file that was executed to
269 create a process running on the remote system.
272 Select the filesystem on which vFile: operations with filename
273 arguments will operate. This is required for GDB to be able to
274 access files on remote targets where the remote stub does not
275 share a common filesystem with the inferior(s).
278 Indicates that a fork system call was executed.
281 Indicates that a vfork system call was executed.
283 vforkdone stop reason
284 Indicates that a vfork child of the specified process has executed
285 an exec or exit, allowing the vfork parent to resume execution.
287 fork-events and vfork-events features in qSupported
288 The qSupported packet allows GDB to request support for fork and
289 vfork events using new 'gdbfeatures' fork-events and vfork-events,
290 and the qSupported response can contain the corresponding
291 'stubfeatures'. Set and show commands can be used to display
292 whether these features are enabled.
294 * Extended-remote fork events
296 ** GDB now has support for fork events on extended-remote Linux
297 targets. For targets with Linux kernels 2.5.60 and later, this
298 enables follow-fork-mode and detach-on-fork for both fork and
299 vfork, as well as fork and vfork catchpoints.
301 * The info record command now shows the recording format and the
302 branch tracing configuration for the current thread when using
303 the btrace record target.
304 For the BTS format, it shows the ring buffer size.
306 * GDB now has support for DTrace USDT (Userland Static Defined
307 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
309 * GDB now supports access to vector registers on S/390 GNU/Linux
312 * Removed command line options
314 -xdb HP-UX XDB compatibility mode.
316 * Removed targets and native configurations
318 HP/PA running HP-UX hppa*-*-hpux*
319 Itanium running HP-UX ia64-*-hpux*
321 * New configure options
324 This configure option allows the user to build GDB with support for
325 Intel(R) Processor Trace (default: auto). This requires libipt.
327 --with-libipt-prefix=PATH
328 Specify the path to the version of libipt that GDB should use.
329 $PATH/include should contain the intel-pt.h header and
330 $PATH/lib should contain the libipt.so library.
332 *** Changes in GDB 7.9.1
336 ** Xmethods can now specify a result type.
338 *** Changes in GDB 7.9
340 * GDB now supports hardware watchpoints on x86 GNU Hurd.
344 ** You can now access frame registers from Python scripts.
345 ** New attribute 'producer' for gdb.Symtab objects.
346 ** gdb.Objfile objects have a new attribute "progspace",
347 which is the gdb.Progspace object of the containing program space.
348 ** gdb.Objfile objects have a new attribute "owner".
349 ** gdb.Objfile objects have a new attribute "build_id",
350 which is the build ID generated when the file was built.
351 ** gdb.Objfile objects have a new method "add_separate_debug_file".
352 ** A new event "gdb.clear_objfiles" has been added, triggered when
353 selecting a new file to debug.
354 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
355 ** New function gdb.lookup_objfile.
357 New events which are triggered when GDB modifies the state of the
360 ** gdb.events.inferior_call_pre: Function call is about to be made.
361 ** gdb.events.inferior_call_post: Function call has just been made.
362 ** gdb.events.memory_changed: A memory location has been altered.
363 ** gdb.events.register_changed: A register has been altered.
365 * New Python-based convenience functions:
367 ** $_caller_is(name [, number_of_frames])
368 ** $_caller_matches(regexp [, number_of_frames])
369 ** $_any_caller_is(name [, number_of_frames])
370 ** $_any_caller_matches(regexp [, number_of_frames])
372 * GDB now supports the compilation and injection of source code into
373 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
374 to compile the source code to object code, and if successful, inject
375 and execute that code within the current context of the inferior.
376 Currently the C language is supported. The commands used to
377 interface with this new feature are:
379 compile code [-raw|-r] [--] [source code]
380 compile file [-raw|-r] filename
384 demangle [-l language] [--] name
385 Demangle "name" in the specified language, or the current language
386 if elided. This command is renamed from the "maint demangle" command.
387 The latter is kept as a no-op to avoid "maint demangle" being interpreted
388 as "maint demangler-warning".
390 queue-signal signal-name-or-number
391 Queue a signal to be delivered to the thread when it is resumed.
393 add-auto-load-scripts-directory directory
394 Add entries to the list of directories from which to load auto-loaded
397 maint print user-registers
398 List all currently available "user" registers.
400 compile code [-r|-raw] [--] [source code]
401 Compile, inject, and execute in the inferior the executable object
402 code produced by compiling the provided source code.
404 compile file [-r|-raw] filename
405 Compile and inject into the inferior the executable object code
406 produced by compiling the source code stored in the filename
409 * On resume, GDB now always passes the signal the program had stopped
410 for to the thread the signal was sent to, even if the user changed
411 threads before resuming. Previously GDB would often (but not
412 always) deliver the signal to the thread that happens to be current
415 * Conversely, the "signal" command now consistently delivers the
416 requested signal to the current thread. GDB now asks for
417 confirmation if the program had stopped for a signal and the user
418 switched threads meanwhile.
420 * "breakpoint always-inserted" modes "off" and "auto" merged.
422 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
423 won't remove breakpoints from the target until all threads stop,
424 even in non-stop mode. The "auto" mode has been removed, and "off"
425 is now the default mode.
429 set debug symbol-lookup
430 show debug symbol-lookup
431 Control display of debugging info regarding symbol lookup.
435 ** The -list-thread-groups command outputs an exit-code field for
436 inferiors that have exited.
440 MIPS SDE mips*-sde*-elf*
444 Support for these obsolete configurations has been removed.
446 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
447 SGI Irix-5.x mips-*-irix5*
448 SGI Irix-6.x mips-*-irix6*
449 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
450 VAX running Ultrix vax-*-ultrix*
452 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
453 and "assf"), have been removed. Use the "sharedlibrary" command, or
454 its alias "share", instead.
456 *** Changes in GDB 7.8
458 * New command line options
461 This is an alias for the --data-directory option.
463 * GDB supports printing and modifying of variable length automatic arrays
464 as specified in ISO C99.
466 * The ARM simulator now supports instruction level tracing
467 with or without disassembly.
471 GDB now has support for scripting using Guile. Whether this is
472 available is determined at configure time.
473 Guile version 2.0 or greater is required.
474 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
476 * New commands (for set/show, see "New options" below)
480 Invoke CODE by passing it to the Guile interpreter.
484 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
486 info auto-load guile-scripts [regexp]
487 Print the list of automatically loaded Guile scripts.
489 * The source command is now capable of sourcing Guile scripts.
490 This feature is dependent on the debugger being built with Guile support.
494 set print symbol-loading (off|brief|full)
495 show print symbol-loading
496 Control whether to print informational messages when loading symbol
497 information for a file. The default is "full", but when debugging
498 programs with large numbers of shared libraries the amount of output
501 set guile print-stack (none|message|full)
502 show guile print-stack
503 Show a stack trace when an error is encountered in a Guile script.
505 set auto-load guile-scripts (on|off)
506 show auto-load guile-scripts
507 Control auto-loading of Guile script files.
509 maint ada set ignore-descriptive-types (on|off)
510 maint ada show ignore-descriptive-types
511 Control whether the debugger should ignore descriptive types in Ada
512 programs. The default is not to ignore the descriptive types. See
513 the user manual for more details on descriptive types and the intended
514 usage of this option.
516 set auto-connect-native-target
518 Control whether GDB is allowed to automatically connect to the
519 native target for the run, attach, etc. commands when not connected
520 to any target yet. See also "target native" below.
522 set record btrace replay-memory-access (read-only|read-write)
523 show record btrace replay-memory-access
524 Control what memory accesses are allowed during replay.
526 maint set target-async (on|off)
527 maint show target-async
528 This controls whether GDB targets operate in synchronous or
529 asynchronous mode. Normally the default is asynchronous, if it is
530 available; but this can be changed to more easily debug problems
531 occurring only in synchronous mode.
533 set mi-async (on|off)
535 Control whether MI asynchronous mode is preferred. This supersedes
536 "set target-async" of previous GDB versions.
538 * "set target-async" is deprecated as a CLI option and is now an alias
539 for "set mi-async" (only puts MI into async mode).
541 * Background execution commands (e.g., "c&", "s&", etc.) are now
542 possible ``out of the box'' if the target supports them. Previously
543 the user would need to explicitly enable the possibility with the
544 "set target-async on" command.
546 * New features in the GDB remote stub, GDBserver
548 ** New option --debug-format=option1[,option2,...] allows one to add
549 additional text to each output. At present only timestamps
550 are supported: --debug-format=timestamps.
551 Timestamps can also be turned on with the
552 "monitor set debug-format timestamps" command from GDB.
554 * The 'record instruction-history' command now starts counting instructions
555 at one. This also affects the instruction ranges reported by the
556 'record function-call-history' command when given the /i modifier.
558 * The command 'record function-call-history' supports a new modifier '/c' to
559 indent the function names based on their call stack depth.
560 The fields for the '/i' and '/l' modifier have been reordered.
561 The source line range is now prefixed with 'at'.
562 The instruction range is now prefixed with 'inst'.
563 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
564 "record instruction-history" and "list" commands.
566 * The ranges given as arguments to the 'record function-call-history' and
567 'record instruction-history' commands are now inclusive.
569 * The btrace record target now supports the 'record goto' command.
570 For locations inside the execution trace, the back trace is computed
571 based on the information stored in the execution trace.
573 * The btrace record target supports limited reverse execution and replay.
574 The target does not record data and therefore does not allow reading
577 * The "catch syscall" command now works on s390*-linux* targets.
579 * The "compare-sections" command is no longer specific to target
580 remote. It now works with all targets.
582 * All native targets are now consistently called "native".
583 Consequently, the "target child", "target GNU", "target djgpp",
584 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
585 commands have been replaced with "target native". The QNX/NTO port
586 leaves the "procfs" target in place and adds a "native" target for
587 consistency with other ports. The impact on users should be minimal
588 as these commands previously either throwed an error, or were
589 no-ops. The target's name is visible in the output of the following
590 commands: "help target", "info target", "info files", "maint print
593 * The "target native" command now connects to the native target. This
594 can be used to launch native programs even when "set
595 auto-connect-native-target" is set to off.
597 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
599 * Support for Intel(R) AVX-512 registers on GNU/Linux.
600 Support displaying and modifying Intel(R) AVX-512 registers
601 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
605 qXfer:btrace:read's annex
606 The qXfer:btrace:read packet supports a new annex 'delta' to read
607 branch trace incrementally.
611 ** Valid Python operations on gdb.Value objects representing
612 structs/classes invoke the corresponding overloaded operators if
614 ** New `Xmethods' feature in the Python API. Xmethods are
615 additional methods or replacements for existing methods of a C++
616 class. This feature is useful for those cases where a method
617 defined in C++ source code could be inlined or optimized out by
618 the compiler, making it unavailable to GDB.
621 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
623 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
624 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
625 its alias "share", instead.
627 * The commands "set remotebaud" and "show remotebaud" are no longer
628 supported. Use "set serial baud" and "show serial baud" (respectively)
633 ** A new option "-gdb-set mi-async" replaces "-gdb-set
634 target-async". The latter is left as a deprecated alias of the
635 former for backward compatibility. If the target supports it,
636 CLI background execution commands are now always possible by
637 default, independently of whether the frontend stated a
638 preference for asynchronous execution with "-gdb-set mi-async".
639 Previously "-gdb-set target-async off" affected both MI execution
640 commands and CLI execution commands.
642 *** Changes in GDB 7.7
644 * Improved support for process record-replay and reverse debugging on
645 arm*-linux* targets. Support for thumb32 and syscall instruction
646 recording has been added.
648 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
650 * GDB now supports Fission DWP file format version 2.
651 http://gcc.gnu.org/wiki/DebugFission
653 * New convenience function "$_isvoid", to check whether an expression
654 is void. A void expression is an expression where the type of the
655 result is "void". For example, some convenience variables may be
656 "void" when evaluated (e.g., "$_exitcode" before the execution of
657 the program being debugged; or an undefined convenience variable).
658 Another example, when calling a function whose return type is
661 * The "maintenance print objfiles" command now takes an optional regexp.
663 * The "catch syscall" command now works on arm*-linux* targets.
665 * GDB now consistently shows "<not saved>" when printing values of
666 registers the debug info indicates have not been saved in the frame
667 and there's nowhere to retrieve them from
668 (callee-saved/call-clobbered registers):
673 (gdb) info registers rax
676 Before, the former would print "<optimized out>", and the latter
677 "*value not available*".
679 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
684 ** Frame filters and frame decorators have been added.
685 ** Temporary breakpoints are now supported.
686 ** Line tables representation has been added.
687 ** New attribute 'parent_type' for gdb.Field objects.
688 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
689 ** New attribute 'name' for gdb.Type objects.
693 Nios II ELF nios2*-*-elf
694 Nios II GNU/Linux nios2*-*-linux
695 Texas Instruments MSP430 msp430*-*-elf
697 * Removed native configurations
699 Support for these a.out NetBSD and OpenBSD obsolete configurations has
700 been removed. ELF variants of these configurations are kept supported.
702 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
703 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
704 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
705 i[34567]86-*-openbsd3.[0-3]
706 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
707 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
708 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
712 Like "catch throw", but catches a re-thrown exception.
714 Renamed from old "maint check-symtabs".
716 Perform consistency checks on symtabs.
718 Expand symtabs matching an optional regexp.
721 Display the details of GDB configure-time options.
723 maint set|show per-command
724 maint set|show per-command space
725 maint set|show per-command time
726 maint set|show per-command symtab
727 Enable display of per-command gdb resource usage.
729 remove-symbol-file FILENAME
730 remove-symbol-file -a ADDRESS
731 Remove a symbol file added via add-symbol-file. The file to remove
732 can be identified by its filename or by an address that lies within
733 the boundaries of this symbol file in memory.
736 info exceptions REGEXP
737 Display the list of Ada exceptions defined in the program being
738 debugged. If provided, only the exceptions whose names match REGEXP
743 set debug symfile off|on
745 Control display of debugging info regarding reading symbol files and
746 symbol tables within those files
748 set print raw frame-arguments
749 show print raw frame-arguments
750 Set/show whether to print frame arguments in raw mode,
751 disregarding any defined pretty-printers.
753 set remote trace-status-packet
754 show remote trace-status-packet
755 Set/show the use of remote protocol qTStatus packet.
759 Control display of debugging messages related to Nios II targets.
763 Control whether target-assisted range stepping is enabled.
765 set startup-with-shell
766 show startup-with-shell
767 Specifies whether Unix child processes are started via a shell or
772 Use the target memory cache for accesses to the code segment. This
773 improves performance of remote debugging (particularly disassembly).
775 * You can now use a literal value 'unlimited' for options that
776 interpret 0 or -1 as meaning "unlimited". E.g., "set
777 trace-buffer-size unlimited" is now an alias for "set
778 trace-buffer-size -1" and "set height unlimited" is now an alias for
781 * The "set debug symtab-create" debugging option of GDB has been changed to
782 accept a verbosity level. 0 means "off", 1 provides basic debugging
783 output, and values of 2 or greater provides more verbose output.
785 * New command-line options
787 Display the details of GDB configure-time options.
789 * The command 'tsave' can now support new option '-ctf' to save trace
790 buffer in Common Trace Format.
792 * Newly installed $prefix/bin/gcore acts as a shell interface for the
795 * GDB now implements the the C++ 'typeid' operator.
797 * The new convenience variable $_exception holds the exception being
798 thrown or caught at an exception-related catchpoint.
800 * The exception-related catchpoints, like "catch throw", now accept a
801 regular expression which can be used to filter exceptions by type.
803 * The new convenience variable $_exitsignal is automatically set to
804 the terminating signal number when the program being debugged dies
805 due to an uncaught signal.
809 ** All MI commands now accept an optional "--language" option.
810 Support for this feature can be verified by using the "-list-features"
811 command, which should contain "language-option".
813 ** The new command -info-gdb-mi-command allows the user to determine
814 whether a GDB/MI command is supported or not.
816 ** The "^error" result record returned when trying to execute an undefined
817 GDB/MI command now provides a variable named "code" whose content is the
818 "undefined-command" error code. Support for this feature can be verified
819 by using the "-list-features" command, which should contain
820 "undefined-command-error-code".
822 ** The -trace-save MI command can optionally save trace buffer in Common
825 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
827 ** The command -data-list-register-values now accepts an optional
828 "--skip-unavailable" option. When used, only the available registers
831 ** The new command -trace-frame-collected dumps collected variables,
832 computed expressions, tvars, memory and registers in a traceframe.
834 ** The commands -stack-list-locals, -stack-list-arguments and
835 -stack-list-variables now accept an option "--skip-unavailable".
836 When used, only the available locals or arguments are displayed.
838 ** The -exec-run command now accepts an optional "--start" option.
839 When used, the command follows the same semantics as the "start"
840 command, stopping the program's execution at the start of its
841 main subprogram. Support for this feature can be verified using
842 the "-list-features" command, which should contain
843 "exec-run-start-option".
845 ** The new commands -catch-assert and -catch-exceptions insert
846 catchpoints stopping the program when Ada exceptions are raised.
848 ** The new command -info-ada-exceptions provides the equivalent of
849 the new "info exceptions" command.
851 * New system-wide configuration scripts
852 A GDB installation now provides scripts suitable for use as system-wide
853 configuration scripts for the following systems:
857 * GDB now supports target-assigned range stepping with remote targets.
858 This improves the performance of stepping source lines by reducing
859 the number of control packets from/to GDB. See "New remote packets"
862 * GDB now understands the element 'tvar' in the XML traceframe info.
863 It has the id of the collected trace state variables.
865 * On S/390 targets that provide the transactional-execution feature,
866 the program interruption transaction diagnostic block (TDB) is now
867 represented as a number of additional "registers" in GDB.
873 The vCont packet supports a new 'r' action, that tells the remote
874 stub to step through an address range itself, without GDB
875 involvemement at each single-step.
877 qXfer:libraries-svr4:read's annex
878 The previously unused annex of the qXfer:libraries-svr4:read packet
879 is now used to support passing an argument list. The remote stub
880 reports support for this argument list to GDB's qSupported query.
881 The defined arguments are "start" and "prev", used to reduce work
882 necessary for library list updating, resulting in significant
885 * New features in the GDB remote stub, GDBserver
887 ** GDBserver now supports target-assisted range stepping. Currently
888 enabled on x86/x86_64 GNU/Linux targets.
890 ** GDBserver now adds element 'tvar' in the XML in the reply to
891 'qXfer:traceframe-info:read'. It has the id of the collected
892 trace state variables.
894 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
897 * New 'z' formatter for printing and examining memory, this displays the
898 value as hexadecimal zero padded on the left to the size of the type.
900 * GDB can now use Windows x64 unwinding data.
902 * The "set remotebaud" command has been replaced by "set serial baud".
903 Similarly, "show remotebaud" has been replaced by "show serial baud".
904 The "set remotebaud" and "show remotebaud" commands are still available
905 to provide backward compatibility with older versions of GDB.
907 *** Changes in GDB 7.6
909 * Target record has been renamed to record-full.
910 Record/replay is now enabled with the "record full" command.
911 This also affects settings that are associated with full record/replay
912 that have been moved from "set/show record" to "set/show record full":
914 set|show record full insn-number-max
915 set|show record full stop-at-limit
916 set|show record full memory-query
918 * A new record target "record-btrace" has been added. The new target
919 uses hardware support to record the control-flow of a process. It
920 does not support replaying the execution, but it implements the
921 below new commands for investigating the recorded execution log.
922 This new recording method can be enabled using:
926 The "record-btrace" target is only available on Intel Atom processors
927 and requires a Linux kernel 2.6.32 or later.
929 * Two new commands have been added for record/replay to give information
930 about the recorded execution without having to replay the execution.
931 The commands are only supported by "record btrace".
933 record instruction-history prints the execution history at
934 instruction granularity
936 record function-call-history prints the execution history at
939 * New native configurations
941 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
942 FreeBSD/powerpc powerpc*-*-freebsd
943 x86_64/Cygwin x86_64-*-cygwin*
944 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
948 ARM AArch64 aarch64*-*-elf
949 ARM AArch64 GNU/Linux aarch64*-*-linux
950 Lynx 178 PowerPC powerpc-*-lynx*178
951 x86_64/Cygwin x86_64-*-cygwin*
952 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
954 * If the configured location of system.gdbinit file (as given by the
955 --with-system-gdbinit option at configure time) is in the
956 data-directory (as specified by --with-gdb-datadir at configure
957 time) or in one of its subdirectories, then GDB will look for the
958 system-wide init file in the directory specified by the
959 --data-directory command-line option.
961 * New command line options:
963 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
964 other initialization files, unlike -nx which disables all of them.
966 * Removed command line options
968 -epoch This was used by the gdb mode in Epoch, an ancient fork of
971 * The 'ptype' and 'whatis' commands now accept an argument to control
974 * 'info proc' now works on some core files.
978 ** Vectors can be created with gdb.Type.vector.
980 ** Python's atexit.register now works in GDB.
982 ** Types can be pretty-printed via a Python API.
984 ** Python 3 is now supported (in addition to Python 2.4 or later)
986 ** New class gdb.Architecture exposes GDB's internal representation
987 of architecture in the Python API.
989 ** New method Frame.architecture returns the gdb.Architecture object
990 corresponding to the frame's architecture.
992 * New Python-based convenience functions:
994 ** $_memeq(buf1, buf2, length)
995 ** $_streq(str1, str2)
997 ** $_regex(str, regex)
999 * The 'cd' command now defaults to using '~' (the home directory) if not
1002 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1003 default for GCC since November 2000.
1005 * The command 'forward-search' can now be abbreviated as 'fo'.
1007 * The command 'info tracepoints' can now display 'installed on target'
1008 or 'not installed on target' for each non-pending location of tracepoint.
1010 * New configure options
1012 --enable-libmcheck/--disable-libmcheck
1013 By default, development versions are built with -lmcheck on hosts
1014 that support it, in order to help track memory corruption issues.
1015 Release versions, on the other hand, are built without -lmcheck
1016 by default. The --enable-libmcheck/--disable-libmcheck configure
1017 options allow the user to override that default.
1018 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1019 This configure option allows the user to build GDB with
1020 libbabeltrace using which GDB can read Common Trace Format data.
1022 * New commands (for set/show, see "New options" below)
1025 Catch signals. This is similar to "handle", but allows commands and
1026 conditions to be attached.
1029 List the BFDs known to GDB.
1031 python-interactive [command]
1033 Start a Python interactive prompt, or evaluate the optional command
1034 and print the result of expressions.
1037 "py" is a new alias for "python".
1039 enable type-printer [name]...
1040 disable type-printer [name]...
1041 Enable or disable type printers.
1045 ** For the Renesas Super-H architecture, the "regs" command has been removed
1046 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1051 set print type methods (on|off)
1052 show print type methods
1053 Control whether method declarations are displayed by "ptype".
1054 The default is to show them.
1056 set print type typedefs (on|off)
1057 show print type typedefs
1058 Control whether typedef definitions are displayed by "ptype".
1059 The default is to show them.
1061 set filename-display basename|relative|absolute
1062 show filename-display
1063 Control the way in which filenames is displayed.
1064 The default is "relative", which preserves previous behavior.
1066 set trace-buffer-size
1067 show trace-buffer-size
1068 Request target to change the size of trace buffer.
1070 set remote trace-buffer-size-packet auto|on|off
1071 show remote trace-buffer-size-packet
1072 Control the use of the remote protocol `QTBuffer:size' packet.
1076 Control display of debugging messages related to ARM AArch64.
1079 set debug coff-pe-read
1080 show debug coff-pe-read
1081 Control display of debugging messages related to reading of COFF/PE
1086 Control display of debugging messages related to Mach-O symbols
1089 set debug notification
1090 show debug notification
1091 Control display of debugging info for async remote notification.
1095 ** Command parameter changes are now notified using new async record
1096 "=cmd-param-changed".
1097 ** Trace frame changes caused by command "tfind" are now notified using
1098 new async record "=traceframe-changed".
1099 ** The creation, deletion and modification of trace state variables
1100 are now notified using new async records "=tsv-created",
1101 "=tsv-deleted" and "=tsv-modified".
1102 ** The start and stop of process record are now notified using new
1103 async record "=record-started" and "=record-stopped".
1104 ** Memory changes are now notified using new async record
1106 ** The data-disassemble command response will include a "fullname" field
1107 containing the absolute file name when source has been requested.
1108 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1109 command, to allow pattern filling of memory areas.
1110 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1111 library load/unload events.
1112 ** The response to breakpoint commands and breakpoint async records
1113 includes an "installed" field containing a boolean state about each
1114 non-pending tracepoint location is whether installed on target or not.
1115 ** Output of the "-trace-status" command includes a "trace-file" field
1116 containing the name of the trace file being examined. This field is
1117 optional, and only present when examining a trace file.
1118 ** The "fullname" field is now always present along with the "file" field,
1119 even if the file cannot be found by GDB.
1121 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1122 You must have the LZMA library available when configuring GDB for this
1123 feature to be enabled. For more information, see:
1124 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1126 * New remote packets
1129 Set the size of trace buffer. The remote stub reports support for this
1130 packet to gdb's qSupported query.
1133 Enable Branch Trace Store (BTS)-based branch tracing for the current
1134 thread. The remote stub reports support for this packet to gdb's
1138 Disable branch tracing for the current thread. The remote stub reports
1139 support for this packet to gdb's qSupported query.
1142 Read the traced branches for the current thread. The remote stub
1143 reports support for this packet to gdb's qSupported query.
1145 *** Changes in GDB 7.5
1147 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1148 for more x32 ABI info.
1150 * GDB now supports access to MIPS DSP registers on Linux targets.
1152 * GDB now supports debugging microMIPS binaries.
1154 * The "info os" command on GNU/Linux can now display information on
1155 several new classes of objects managed by the operating system:
1156 "info os procgroups" lists process groups
1157 "info os files" lists file descriptors
1158 "info os sockets" lists internet-domain sockets
1159 "info os shm" lists shared-memory regions
1160 "info os semaphores" lists semaphores
1161 "info os msg" lists message queues
1162 "info os modules" lists loaded kernel modules
1164 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1165 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1166 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1167 options and inspect the probe arguments using the new $_probe_arg family
1168 of convenience variables. You can obtain more information about SystemTap
1169 in <http://sourceware.org/systemtap/>.
1171 * GDB now supports reversible debugging on ARM, it allows you to
1172 debug basic ARM and THUMB instructions, and provides
1173 record/replay support.
1175 * The option "symbol-reloading" has been deleted as it is no longer used.
1179 ** GDB commands implemented in Python can now be put in command class
1182 ** The "maint set python print-stack on|off" is now deleted.
1184 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1185 apply "flag enum"-style pretty-printing to any enum.
1187 ** gdb.lookup_symbol can now work when there is no current frame.
1189 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1190 the source at which the symbol was defined.
1192 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1193 method 'value'. The former indicates whether the symbol needs a
1194 frame in order to compute its value, and the latter computes the
1197 ** A new method 'referenced_value' on gdb.Value objects which can
1198 dereference pointer as well as C++ reference values.
1200 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1201 which return the global and static blocks (as gdb.Block objects),
1202 of the underlying symbol table, respectively.
1204 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1205 object associated with a PC value.
1207 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1208 of the address range occupied by code for the current source line.
1210 * Go language support.
1211 GDB now supports debugging programs written in the Go programming
1214 * GDBserver now supports stdio connections.
1215 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1217 * The binary "gdbtui" can no longer be built or installed.
1218 Use "gdb -tui" instead.
1220 * GDB will now print "flag" enums specially. A flag enum is one where
1221 all the enumerator values have no bits in common when pairwise
1222 "and"ed. When printing a value whose type is a flag enum, GDB will
1223 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1224 (gdb) print (enum E) 3
1227 * The filename part of a linespec will now match trailing components
1228 of a source file name. For example, "break gcc/expr.c:1000" will
1229 now set a breakpoint in build/gcc/expr.c, but not
1230 build/libcpp/expr.c.
1232 * The "info proc" and "generate-core-file" commands will now also
1233 work on remote targets connected to GDBserver on Linux.
1235 * The command "info catch" has been removed. It has been disabled
1236 since December 2007.
1238 * The "catch exception" and "catch assert" commands now accept
1239 a condition at the end of the command, much like the "break"
1240 command does. For instance:
1242 (gdb) catch exception Constraint_Error if Barrier = True
1244 Previously, it was possible to add a condition to such catchpoints,
1245 but it had to be done as a second step, after the catchpoint had been
1246 created, using the "condition" command.
1248 * The "info static-tracepoint-marker" command will now also work on
1249 native Linux targets with in-process agent.
1251 * GDB can now set breakpoints on inlined functions.
1253 * The .gdb_index section has been updated to include symbols for
1254 inlined functions. GDB will ignore older .gdb_index sections by
1255 default, which could cause symbol files to be loaded more slowly
1256 until their .gdb_index sections can be recreated. The new command
1257 "set use-deprecated-index-sections on" will cause GDB to use any older
1258 .gdb_index sections it finds. This will restore performance, but the
1259 ability to set breakpoints on inlined functions will be lost in symbol
1260 files with older .gdb_index sections.
1262 The .gdb_index section has also been updated to record more information
1263 about each symbol. This speeds up the "info variables", "info functions"
1264 and "info types" commands when used with programs having the .gdb_index
1265 section, as well as speeding up debugging with shared libraries using
1266 the .gdb_index section.
1268 * Ada support for GDB/MI Variable Objects has been added.
1270 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1275 ** New command -info-os is the MI equivalent of "info os".
1277 ** Output logs ("set logging" and related) now include MI output.
1281 ** "set use-deprecated-index-sections on|off"
1282 "show use-deprecated-index-sections on|off"
1283 Controls the use of deprecated .gdb_index sections.
1285 ** "catch load" and "catch unload" can be used to stop when a shared
1286 library is loaded or unloaded, respectively.
1288 ** "enable count" can be used to auto-disable a breakpoint after
1291 ** "info vtbl" can be used to show the virtual method tables for
1292 C++ and Java objects.
1294 ** "explore" and its sub commands "explore value" and "explore type"
1295 can be used to recursively explore values and types of
1296 expressions. These commands are available only if GDB is
1297 configured with '--with-python'.
1299 ** "info auto-load" shows status of all kinds of auto-loaded files,
1300 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1301 sequences of commands files, "info auto-load python-scripts"
1302 shows status of auto-loading Python script files,
1303 "info auto-load local-gdbinit" shows status of loading init file
1304 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1305 status of inferior specific thread debugging shared library loading.
1307 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1308 and "show auto-load-scripts" commands have been deprecated, use their
1309 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1310 and "show auto-load python-scripts" counterparts instead.
1312 ** "dprintf location,format,args..." creates a dynamic printf, which
1313 is basically a breakpoint that does a printf and immediately
1314 resumes your program's execution, so it is like a printf that you
1315 can insert dynamically at runtime instead of at compiletime.
1317 ** "set print symbol"
1319 Controls whether GDB attempts to display the symbol, if any,
1320 corresponding to addresses it prints. This defaults to "on", but
1321 you can set it to "off" to restore GDB's previous behavior.
1323 * Deprecated commands
1325 ** For the Renesas Super-H architecture, the "regs" command has been
1326 deprecated, and "info all-registers" should be used instead.
1330 Renesas RL78 rl78-*-elf
1331 HP OpenVMS ia64 ia64-hp-openvms*
1333 * GDBserver supports evaluation of breakpoint conditions. When
1334 support is advertised by GDBserver, GDB may be told to send the
1335 breakpoint conditions in bytecode form to GDBserver. GDBserver
1336 will only report the breakpoint trigger to GDB when its condition
1341 set mips compression
1342 show mips compression
1343 Select the compressed ISA encoding used in functions that have no symbol
1344 information available. The encoding can be set to either of:
1347 and is updated automatically from ELF file flags if available.
1349 set breakpoint condition-evaluation
1350 show breakpoint condition-evaluation
1351 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1352 GDBserver ("target"). Default option "auto" chooses the most efficient
1354 This option can improve debugger efficiency depending on the speed of the
1358 Disable auto-loading globally.
1361 Show auto-loading setting of all kinds of auto-loaded files.
1363 set auto-load gdb-scripts on|off
1364 show auto-load gdb-scripts
1365 Control auto-loading of GDB canned sequences of commands files.
1367 set auto-load python-scripts on|off
1368 show auto-load python-scripts
1369 Control auto-loading of Python script files.
1371 set auto-load local-gdbinit on|off
1372 show auto-load local-gdbinit
1373 Control loading of init file (.gdbinit) from current directory.
1375 set auto-load libthread-db on|off
1376 show auto-load libthread-db
1377 Control auto-loading of inferior specific thread debugging shared library.
1379 set auto-load scripts-directory <dir1>[:<dir2>...]
1380 show auto-load scripts-directory
1381 Set a list of directories from which to load auto-loaded scripts.
1382 Automatically loaded Python scripts and GDB scripts are located in one
1383 of the directories listed by this option.
1384 The delimiter (':' above) may differ according to the host platform.
1386 set auto-load safe-path <dir1>[:<dir2>...]
1387 show auto-load safe-path
1388 Set a list of directories from which it is safe to auto-load files.
1389 The delimiter (':' above) may differ according to the host platform.
1391 set debug auto-load on|off
1392 show debug auto-load
1393 Control display of debugging info for auto-loading the files above.
1395 set dprintf-style gdb|call|agent
1397 Control the way in which a dynamic printf is performed; "gdb"
1398 requests a GDB printf command, while "call" causes dprintf to call a
1399 function in the inferior. "agent" requests that the target agent
1400 (such as GDBserver) do the printing.
1402 set dprintf-function <expr>
1403 show dprintf-function
1404 set dprintf-channel <expr>
1405 show dprintf-channel
1406 Set the function and optional first argument to the call when using
1407 the "call" style of dynamic printf.
1409 set disconnected-dprintf on|off
1410 show disconnected-dprintf
1411 Control whether agent-style dynamic printfs continue to be in effect
1412 after GDB disconnects.
1414 * New configure options
1416 --with-auto-load-dir
1417 Configure default value for the 'set auto-load scripts-directory'
1418 setting above. It defaults to '$debugdir:$datadir/auto-load',
1419 $debugdir representing global debugging info directories (available
1420 via 'show debug-file-directory') and $datadir representing GDB's data
1421 directory (available via 'show data-directory').
1423 --with-auto-load-safe-path
1424 Configure default value for the 'set auto-load safe-path' setting
1425 above. It defaults to the --with-auto-load-dir setting.
1427 --without-auto-load-safe-path
1428 Set 'set auto-load safe-path' to '/', effectively disabling this
1431 * New remote packets
1433 z0/z1 conditional breakpoints extension
1435 The z0/z1 breakpoint insertion packets have been extended to carry
1436 a list of conditional expressions over to the remote stub depending on the
1437 condition evaluation mode. The use of this extension can be controlled
1438 via the "set remote conditional-breakpoints-packet" command.
1442 Specify the signals which the remote stub may pass to the debugged
1443 program without GDB involvement.
1445 * New command line options
1447 --init-command=FILE, -ix Like --command, -x but execute it
1448 before loading inferior.
1449 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1450 execute it before loading inferior.
1452 *** Changes in GDB 7.4
1454 * GDB now handles ambiguous linespecs more consistently; the existing
1455 FILE:LINE support has been expanded to other types of linespecs. A
1456 breakpoint will now be set on all matching locations in all
1457 inferiors, and locations will be added or removed according to
1460 * GDB now allows you to skip uninteresting functions and files when
1461 stepping with the "skip function" and "skip file" commands.
1463 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1464 and "show remote hardware-watchpoint-length-limit". These allows to
1465 set or show the maximum length limit (in bytes) of a remote
1466 target hardware watchpoint.
1468 This allows e.g. to use "unlimited" hardware watchpoints with the
1469 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1470 watchpoints are slower than real hardware watchpoints but are
1471 significantly faster than gdb software watchpoints.
1475 ** The register_pretty_printer function in module gdb.printing now takes
1476 an optional `replace' argument. If True, the new printer replaces any
1479 ** The "maint set python print-stack on|off" command has been
1480 deprecated and will be deleted in GDB 7.5.
1481 A new command: "set python print-stack none|full|message" has
1482 replaced it. Additionally, the default for "print-stack" is
1483 now "message", which just prints the error message without
1486 ** A prompt substitution hook (prompt_hook) is now available to the
1489 ** A new Python module, gdb.prompt has been added to the GDB Python
1490 modules library. This module provides functionality for
1491 escape sequences in prompts (used by set/show
1492 extended-prompt). These escape sequences are replaced by their
1493 corresponding value.
1495 ** Python commands and convenience-functions located in
1496 'data-directory'/python/gdb/command and
1497 'data-directory'/python/gdb/function are now automatically loaded
1500 ** Blocks now provide four new attributes. global_block and
1501 static_block will return the global and static blocks
1502 respectively. is_static and is_global are boolean attributes
1503 that indicate if the block is one of those two types.
1505 ** Symbols now provide the "type" attribute, the type of the symbol.
1507 ** The "gdb.breakpoint" function has been deprecated in favor of
1510 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1511 of a function. This class is based on the "finish" command
1512 available in the CLI.
1514 ** Type objects for struct and union types now allow access to
1515 the fields using standard Python dictionary (mapping) methods.
1516 For example, "some_type['myfield']" now works, as does
1517 "some_type.items()".
1519 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1522 ** A new function, "deep_items" has been added to the gdb.types
1523 module in the GDB Python modules library. This function returns
1524 an iterator over the fields of a struct or union type. Unlike
1525 the standard Python "iteritems" method, it will recursively traverse
1526 any anonymous fields.
1530 ** "*stopped" events can report several new "reason"s, such as
1533 ** Breakpoint changes are now notified using new async records, like
1534 "=breakpoint-modified".
1536 ** New command -ada-task-info.
1538 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1539 $sdir specifies the default system locations of shared libraries.
1540 $pdir specifies the directory where the libpthread used by the application
1543 GDB no longer looks in $sdir and $pdir after it has searched the directories
1544 mentioned in libthread-db-search-path. If you want to search those
1545 directories, they must be specified in libthread-db-search-path.
1546 The default value of libthread-db-search-path on GNU/Linux and Solaris
1547 systems is now "$sdir:$pdir".
1549 $pdir is not supported by gdbserver, it is currently ignored.
1550 $sdir is supported by gdbserver.
1552 * New configure option --with-iconv-bin.
1553 When using the internationalization support like the one in the GNU C
1554 library, GDB will invoke the "iconv" program to get a list of supported
1555 character sets. If this program lives in a non-standard location, one can
1556 use this option to specify where to find it.
1558 * When natively debugging programs on PowerPC BookE processors running
1559 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1560 watchpoints, which specify a mask in addition to an address to watch.
1561 The mask specifies that some bits of an address (the bits which are
1562 reset in the mask) should be ignored when matching the address accessed
1563 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1564 section in the user manual for more details.
1566 * The new option --once causes GDBserver to stop listening for connections once
1567 the first connection is made. The listening port used by GDBserver will
1568 become available after that.
1570 * New commands "info macros" and "alias" have been added.
1572 * New function parameters suffix @entry specifies value of function parameter
1573 at the time the function got called. Entry values are available only since
1579 "!" is now an alias of the "shell" command.
1580 Note that no space is needed between "!" and SHELL COMMAND.
1584 watch EXPRESSION mask MASK_VALUE
1585 The watch command now supports the mask argument which allows creation
1586 of masked watchpoints, if the current architecture supports this feature.
1588 info auto-load-scripts [REGEXP]
1589 This command was formerly named "maintenance print section-scripts".
1590 It is now generally useful and is no longer a maintenance-only command.
1592 info macro [-all] [--] MACRO
1593 The info macro command has new options `-all' and `--'. The first for
1594 printing all definitions of a macro. The second for explicitly specifying
1595 the end of arguments and the beginning of the macro name in case the macro
1596 name starts with a hyphen.
1598 collect[/s] EXPRESSIONS
1599 The tracepoint collect command now takes an optional modifier "/s"
1600 that directs it to dereference pointer-to-character types and
1601 collect the bytes of memory up to a zero byte. The behavior is
1602 similar to what you see when you use the regular print command on a
1603 string. An optional integer following the "/s" sets a bound on the
1604 number of bytes that will be collected.
1607 The trace start command now interprets any supplied arguments as a
1608 note to be recorded with the trace run, with an effect similar to
1609 setting the variable trace-notes.
1612 The trace stop command now interprets any arguments as a note to be
1613 mentioned along with the tstatus report that the trace was stopped
1614 with a command. The effect is similar to setting the variable
1617 * Tracepoints can now be enabled and disabled at any time after a trace
1618 experiment has been started using the standard "enable" and "disable"
1619 commands. It is now possible to start a trace experiment with no enabled
1620 tracepoints; GDB will display a warning, but will allow the experiment to
1621 begin, assuming that tracepoints will be enabled as needed while the trace
1624 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1625 locations with 4-byte instructions, when they were previously
1626 limited to locations with instructions of 5 bytes or longer.
1630 set debug dwarf2-read
1631 show debug dwarf2-read
1632 Turns on or off display of debugging messages related to reading
1633 DWARF debug info. The default is off.
1635 set debug symtab-create
1636 show debug symtab-create
1637 Turns on or off display of debugging messages related to symbol table
1638 creation. The default is off.
1641 show extended-prompt
1642 Set the GDB prompt, and allow escape sequences to be inserted to
1643 display miscellaneous information (see 'help set extended-prompt'
1644 for the list of sequences). This prompt (and any information
1645 accessed through the escape sequences) is updated every time the
1646 prompt is displayed.
1648 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1649 show print entry-values
1650 Set printing of frame argument values at function entry. In some cases
1651 GDB can determine the value of function argument which was passed by the
1652 function caller, even if the value was modified inside the called function.
1654 set debug entry-values
1655 show debug entry-values
1656 Control display of debugging info for determining frame argument values at
1657 function entry and virtual tail call frames.
1659 set basenames-may-differ
1660 show basenames-may-differ
1661 Set whether a source file may have multiple base names.
1662 (A "base name" is the name of a file with the directory part removed.
1663 Example: The base name of "/home/user/hello.c" is "hello.c".)
1664 If set, GDB will canonicalize file names (e.g., expand symlinks)
1665 before comparing them. Canonicalization is an expensive operation,
1666 but it allows the same file be known by more than one base name.
1667 If not set (the default), all source files are assumed to have just
1668 one base name, and gdb will do file name comparisons more efficiently.
1674 Set a user name and notes for the current and any future trace runs.
1675 This is useful for long-running and/or disconnected traces, to
1676 inform others (or yourself) as to who is running the trace, supply
1677 contact information, or otherwise explain what is going on.
1679 set trace-stop-notes
1680 show trace-stop-notes
1681 Set a note attached to the trace run, that is displayed when the
1682 trace has been stopped by a tstop command. This is useful for
1683 instance as an explanation, if you are stopping a trace run that was
1684 started by someone else.
1686 * New remote packets
1690 Dynamically enable a tracepoint in a started trace experiment.
1694 Dynamically disable a tracepoint in a started trace experiment.
1698 Set the user and notes of the trace run.
1702 Query the current status of a tracepoint.
1706 Query the minimum length of instruction at which a fast tracepoint may
1709 * Dcache size (number of lines) and line-size are now runtime-configurable
1710 via "set dcache line" and "set dcache line-size" commands.
1714 Texas Instruments TMS320C6x tic6x-*-*
1718 Renesas RL78 rl78-*-elf
1720 *** Changes in GDB 7.3.1
1722 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1724 *** Changes in GDB 7.3
1726 * GDB has a new command: "thread find [REGEXP]".
1727 It finds the thread id whose name, target id, or thread extra info
1728 matches the given regular expression.
1730 * The "catch syscall" command now works on mips*-linux* targets.
1732 * The -data-disassemble MI command now supports modes 2 and 3 for
1733 dumping the instruction opcodes.
1735 * New command line options
1737 -data-directory DIR Specify DIR as the "data-directory".
1738 This is mostly for testing purposes.
1740 * The "maint set python auto-load on|off" command has been renamed to
1741 "set auto-load-scripts on|off".
1743 * GDB has a new command: "set directories".
1744 It is like the "dir" command except that it replaces the
1745 source path list instead of augmenting it.
1747 * GDB now understands thread names.
1749 On GNU/Linux, "info threads" will display the thread name as set by
1750 prctl or pthread_setname_np.
1752 There is also a new command, "thread name", which can be used to
1753 assign a name internally for GDB to display.
1756 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1757 has been integrated into GDB.
1761 ** The function gdb.Write now accepts an optional keyword 'stream'.
1762 This keyword, when provided, will direct the output to either
1763 stdout, stderr, or GDB's logging output.
1765 ** Parameters can now be be sub-classed in Python, and in particular
1766 you may implement the get_set_doc and get_show_doc functions.
1767 This improves how Parameter set/show documentation is processed
1768 and allows for more dynamic content.
1770 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1771 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1772 have an is_valid method.
1774 ** Breakpoints can now be sub-classed in Python, and in particular
1775 you may implement a 'stop' function that is executed each time
1776 the inferior reaches that breakpoint.
1778 ** New function gdb.lookup_global_symbol looks up a global symbol.
1780 ** GDB values in Python are now callable if the value represents a
1781 function. For example, if 'some_value' represents a function that
1782 takes two integer parameters and returns a value, you can call
1783 that function like so:
1785 result = some_value (10,20)
1787 ** Module gdb.types has been added.
1788 It contains a collection of utilities for working with gdb.Types objects:
1789 get_basic_type, has_field, make_enum_dict.
1791 ** Module gdb.printing has been added.
1792 It contains utilities for writing and registering pretty-printers.
1793 New classes: PrettyPrinter, SubPrettyPrinter,
1794 RegexpCollectionPrettyPrinter.
1795 New function: register_pretty_printer.
1797 ** New commands "info pretty-printers", "enable pretty-printer" and
1798 "disable pretty-printer" have been added.
1800 ** gdb.parameter("directories") is now available.
1802 ** New function gdb.newest_frame returns the newest frame in the
1805 ** The gdb.InferiorThread class has a new "name" attribute. This
1806 holds the thread's name.
1808 ** Python Support for Inferior events.
1809 Python scripts can add observers to be notified of events
1810 occurring in the process being debugged.
1811 The following events are currently supported:
1812 - gdb.events.cont Continue event.
1813 - gdb.events.exited Inferior exited event.
1814 - gdb.events.stop Signal received, and Breakpoint hit events.
1818 ** GDB now puts template parameters in scope when debugging in an
1819 instantiation. For example, if you have:
1821 template<int X> int func (void) { return X; }
1823 then if you step into func<5>, "print X" will show "5". This
1824 feature requires proper debuginfo support from the compiler; it
1825 was added to GCC 4.5.
1827 ** The motion commands "next", "finish", "until", and "advance" now
1828 work better when exceptions are thrown. In particular, GDB will
1829 no longer lose control of the inferior; instead, the GDB will
1830 stop the inferior at the point at which the exception is caught.
1831 This functionality requires a change in the exception handling
1832 code that was introduced in GCC 4.5.
1834 * GDB now follows GCC's rules on accessing volatile objects when
1835 reading or writing target state during expression evaluation.
1836 One notable difference to prior behavior is that "print x = 0"
1837 no longer generates a read of x; the value of the assignment is
1838 now always taken directly from the value being assigned.
1840 * GDB now has some support for using labels in the program's source in
1841 linespecs. For instance, you can use "advance label" to continue
1842 execution to a label.
1844 * GDB now has support for reading and writing a new .gdb_index
1845 section. This section holds a fast index of DWARF debugging
1846 information and can be used to greatly speed up GDB startup and
1847 operation. See the documentation for `save gdb-index' for details.
1849 * The "watch" command now accepts an optional "-location" argument.
1850 When used, this causes GDB to watch the memory referred to by the
1851 expression. Such a watchpoint is never deleted due to it going out
1854 * GDB now supports thread debugging of core dumps on GNU/Linux.
1856 GDB now activates thread debugging using the libthread_db library
1857 when debugging GNU/Linux core dumps, similarly to when debugging
1858 live processes. As a result, when debugging a core dump file, GDB
1859 is now able to display pthread_t ids of threads. For example, "info
1860 threads" shows the same output as when debugging the process when it
1861 was live. In earlier releases, you'd see something like this:
1864 * 1 LWP 6780 main () at main.c:10
1866 While now you see this:
1869 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1871 It is also now possible to inspect TLS variables when debugging core
1874 When debugging a core dump generated on a machine other than the one
1875 used to run GDB, you may need to point GDB at the correct
1876 libthread_db library with the "set libthread-db-search-path"
1877 command. See the user manual for more details on this command.
1879 * When natively debugging programs on PowerPC BookE processors running
1880 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1881 which stop execution of the inferior whenever it executes an instruction
1882 at any address within the specified range. See the "PowerPC Embedded"
1883 section in the user manual for more details.
1885 * New features in the GDB remote stub, GDBserver
1887 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1888 and i686 LynxOS (version 5.x).
1890 ** GDBserver is now supported on Blackfin Linux.
1892 * New native configurations
1894 ia64 HP-UX ia64-*-hpux*
1898 Analog Devices, Inc. Blackfin Processor bfin-*
1900 * Ada task switching is now supported on sparc-elf targets when
1901 debugging a program using the Ravenscar Profile. For more information,
1902 see the "Tasking Support when using the Ravenscar Profile" section
1903 in the GDB user manual.
1905 * Guile support was removed.
1907 * New features in the GNU simulator
1909 ** The --map-info flag lists all known core mappings.
1911 ** CFI flashes may be simulated via the "cfi" device.
1913 *** Changes in GDB 7.2
1915 * Shared library support for remote targets by default
1917 When GDB is configured for a generic, non-OS specific target, like
1918 for example, --target=arm-eabi or one of the many *-*-elf targets,
1919 GDB now queries remote stubs for loaded shared libraries using the
1920 `qXfer:libraries:read' packet. Previously, shared library support
1921 was always disabled for such configurations.
1925 ** Argument Dependent Lookup (ADL)
1927 In C++ ADL lookup directs function search to the namespaces of its
1928 arguments even if the namespace has not been imported.
1938 Here the compiler will search for `foo' in the namespace of 'b'
1939 and find A::foo. GDB now supports this. This construct is commonly
1940 used in the Standard Template Library for operators.
1942 ** Improved User Defined Operator Support
1944 In addition to member operators, GDB now supports lookup of operators
1945 defined in a namespace and imported with a `using' directive, operators
1946 defined in the global scope, operators imported implicitly from an
1947 anonymous namespace, and the ADL operators mentioned in the previous
1949 GDB now also supports proper overload resolution for all the previously
1950 mentioned flavors of operators.
1952 ** static const class members
1954 Printing of static const class members that are initialized in the
1955 class definition has been fixed.
1957 * Windows Thread Information Block access.
1959 On Windows targets, GDB now supports displaying the Windows Thread
1960 Information Block (TIB) structure. This structure is visible either
1961 by using the new command `info w32 thread-information-block' or, by
1962 dereferencing the new convenience variable named `$_tlb', a
1963 thread-specific pointer to the TIB. This feature is also supported
1964 when remote debugging using GDBserver.
1966 * Static tracepoints
1968 Static tracepoints are calls in the user program into a tracing
1969 library. One such library is a port of the LTTng kernel tracer to
1970 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1971 When debugging with GDBserver, GDB now supports combining the GDB
1972 tracepoint machinery with such libraries. For example: the user can
1973 use GDB to probe a static tracepoint marker (a call from the user
1974 program into the tracing library) with the new "strace" command (see
1975 "New commands" below). This creates a "static tracepoint" in the
1976 breakpoint list, that can be manipulated with the same feature set
1977 as fast and regular tracepoints. E.g., collect registers, local and
1978 global variables, collect trace state variables, and define
1979 tracepoint conditions. In addition, the user can collect extra
1980 static tracepoint marker specific data, by collecting the new
1981 $_sdata internal variable. When analyzing the trace buffer, you can
1982 inspect $_sdata like any other variable available to GDB. For more
1983 information, see the "Tracepoints" chapter in GDB user manual. New
1984 remote packets have been defined to support static tracepoints, see
1985 the "New remote packets" section below.
1987 * Better reconstruction of tracepoints after disconnected tracing
1989 GDB will attempt to download the original source form of tracepoint
1990 definitions when starting a trace run, and then will upload these
1991 upon reconnection to the target, resulting in a more accurate
1992 reconstruction of the tracepoints that are in use on the target.
1996 You can now exercise direct control over the ways that GDB can
1997 affect your program. For instance, you can disallow the setting of
1998 breakpoints, so that the program can run continuously (assuming
1999 non-stop mode). In addition, the "observer" variable is available
2000 to switch all of the different controls; in observer mode, GDB
2001 cannot affect the target's behavior at all, which is useful for
2002 tasks like diagnosing live systems in the field.
2004 * The new convenience variable $_thread holds the number of the
2007 * New remote packets
2011 Return the address of the Windows Thread Information Block of a given thread.
2015 In response to several of the tracepoint packets, the target may now
2016 also respond with a number of intermediate `qRelocInsn' request
2017 packets before the final result packet, to have GDB handle
2018 relocating an instruction to execute at a different address. This
2019 is particularly useful for stubs that support fast tracepoints. GDB
2020 reports support for this feature in the qSupported packet.
2024 List static tracepoint markers in the target program.
2028 List static tracepoint markers at a given address in the target
2031 qXfer:statictrace:read
2033 Read the static trace data collected (by a `collect $_sdata'
2034 tracepoint action). The remote stub reports support for this packet
2035 to gdb's qSupported query.
2039 Send the current settings of GDB's permission flags.
2043 Send part of the source (textual) form of a tracepoint definition,
2044 which includes location, conditional, and action list.
2046 * The source command now accepts a -s option to force searching for the
2047 script in the source search path even if the script name specifies
2050 * New features in the GDB remote stub, GDBserver
2052 - GDBserver now support tracepoints (including fast tracepoints, and
2053 static tracepoints). The feature is currently supported by the
2054 i386-linux and amd64-linux builds. See the "Tracepoints support
2055 in gdbserver" section in the manual for more information.
2057 GDBserver JIT compiles the tracepoint's conditional agent
2058 expression bytecode into native code whenever possible for low
2059 overhead dynamic tracepoints conditionals. For such tracepoints,
2060 an expression that examines program state is evaluated when the
2061 tracepoint is reached, in order to determine whether to capture
2062 trace data. If the condition is simple and false, processing the
2063 tracepoint finishes very quickly and no data is gathered.
2065 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2066 for static tracepoints support.
2068 - GDBserver now supports x86_64 Windows 64-bit debugging.
2070 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2071 it understands register description.
2073 * The --batch flag now disables pagination and queries.
2075 * X86 general purpose registers
2077 GDB now supports reading/writing byte, word and double-word x86
2078 general purpose registers directly. This means you can use, say,
2079 $ah or $ax to refer, respectively, to the byte register AH and
2080 16-bit word register AX that are actually portions of the 32-bit
2081 register EAX or 64-bit register RAX.
2083 * The `commands' command now accepts a range of breakpoints to modify.
2084 A plain `commands' following a command that creates multiple
2085 breakpoints affects all the breakpoints set by that command. This
2086 applies to breakpoints set by `rbreak', and also applies when a
2087 single `break' command creates multiple breakpoints (e.g.,
2088 breakpoints on overloaded c++ functions).
2090 * The `rbreak' command now accepts a filename specification as part of
2091 its argument, limiting the functions selected by the regex to those
2092 in the specified file.
2094 * Support for remote debugging Windows and SymbianOS shared libraries
2095 from Unix hosts has been improved. Non Windows GDB builds now can
2096 understand target reported file names that follow MS-DOS based file
2097 system semantics, such as file names that include drive letters and
2098 use the backslash character as directory separator. This makes it
2099 possible to transparently use the "set sysroot" and "set
2100 solib-search-path" on Unix hosts to point as host copies of the
2101 target's shared libraries. See the new command "set
2102 target-file-system-kind" described below, and the "Commands to
2103 specify files" section in the user manual for more information.
2107 eval template, expressions...
2108 Convert the values of one or more expressions under the control
2109 of the string template to a command line, and call it.
2111 set target-file-system-kind unix|dos-based|auto
2112 show target-file-system-kind
2113 Set or show the assumed file system kind for target reported file
2116 save breakpoints <filename>
2117 Save all current breakpoint definitions to a file suitable for use
2118 in a later debugging session. To read the saved breakpoint
2119 definitions, use the `source' command.
2121 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2124 info static-tracepoint-markers
2125 Display information about static tracepoint markers in the target.
2127 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2128 Define a static tracepoint by probing a marker at the given
2129 function, line, address, or marker ID.
2133 Enable and disable observer mode.
2135 set may-write-registers on|off
2136 set may-write-memory on|off
2137 set may-insert-breakpoints on|off
2138 set may-insert-tracepoints on|off
2139 set may-insert-fast-tracepoints on|off
2140 set may-interrupt on|off
2141 Set individual permissions for GDB effects on the target. Note that
2142 some of these settings can have undesirable or surprising
2143 consequences, particularly when changed in the middle of a session.
2144 For instance, disabling the writing of memory can prevent
2145 breakpoints from being inserted, cause single-stepping to fail, or
2146 even crash your program, if you disable after breakpoints have been
2147 inserted. However, GDB should not crash.
2149 set record memory-query on|off
2150 show record memory-query
2151 Control whether to stop the inferior if memory changes caused
2152 by an instruction cannot be recorded.
2157 The disassemble command now supports "start,+length" form of two arguments.
2161 ** GDB now provides a new directory location, called the python directory,
2162 where Python scripts written for GDB can be installed. The location
2163 of that directory is <data-directory>/python, where <data-directory>
2164 is the GDB data directory. For more details, see section `Scripting
2165 GDB using Python' in the manual.
2167 ** The GDB Python API now has access to breakpoints, symbols, symbol
2168 tables, program spaces, inferiors, threads and frame's code blocks.
2169 Additionally, GDB Parameters can now be created from the API, and
2170 manipulated via set/show in the CLI.
2172 ** New functions gdb.target_charset, gdb.target_wide_charset,
2173 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2175 ** New exception gdb.GdbError.
2177 ** Pretty-printers are now also looked up in the current program space.
2179 ** Pretty-printers can now be individually enabled and disabled.
2181 ** GDB now looks for names of Python scripts to auto-load in a
2182 special section named `.debug_gdb_scripts', in addition to looking
2183 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2185 * Tracepoint actions were unified with breakpoint commands. In particular,
2186 there are no longer differences in "info break" output for breakpoints and
2187 tracepoints and the "commands" command can be used for both tracepoints and
2188 regular breakpoints.
2192 ARM Symbian arm*-*-symbianelf*
2194 * D language support.
2195 GDB now supports debugging programs written in the D programming
2198 * GDB now supports the extended ptrace interface for PowerPC which is
2199 available since Linux kernel version 2.6.34. This automatically enables
2200 any hardware breakpoints and additional hardware watchpoints available in
2201 the processor. The old ptrace interface exposes just one hardware
2202 watchpoint and no hardware breakpoints.
2204 * GDB is now able to use the Data Value Compare (DVC) register available on
2205 embedded PowerPC processors to implement in hardware simple watchpoint
2206 conditions of the form:
2208 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2210 This works in native GDB running on Linux kernels with the extended ptrace
2211 interface mentioned above.
2213 *** Changes in GDB 7.1
2217 ** Namespace Support
2219 GDB now supports importing of namespaces in C++. This enables the
2220 user to inspect variables from imported namespaces. Support for
2221 namepace aliasing has also been added. So, if a namespace is
2222 aliased in the current scope (e.g. namepace C=A; ) the user can
2223 print variables using the alias (e.g. (gdb) print C::x).
2227 All known bugs relating to the printing of virtual base class were
2228 fixed. It is now possible to call overloaded static methods using a
2233 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2234 and reinterpret_cast<> are now handled by the C++ expression parser.
2238 Xilinx MicroBlaze microblaze-*-*
2243 Xilinx MicroBlaze microblaze
2246 * Multi-program debugging.
2248 GDB now has support for multi-program (a.k.a. multi-executable or
2249 multi-exec) debugging. This allows for debugging multiple inferiors
2250 simultaneously each running a different program under the same GDB
2251 session. See "Debugging Multiple Inferiors and Programs" in the
2252 manual for more information. This implied some user visible changes
2253 in the multi-inferior support. For example, "info inferiors" now
2254 lists inferiors that are not running yet or that have exited
2255 already. See also "New commands" and "New options" below.
2257 * New tracing features
2259 GDB's tracepoint facility now includes several new features:
2261 ** Trace state variables
2263 GDB tracepoints now include support for trace state variables, which
2264 are variables managed by the target agent during a tracing
2265 experiment. They are useful for tracepoints that trigger each
2266 other, so for instance one tracepoint can count hits in a variable,
2267 and then a second tracepoint has a condition that is true when the
2268 count reaches a particular value. Trace state variables share the
2269 $-syntax of GDB convenience variables, and can appear in both
2270 tracepoint actions and condition expressions. Use the "tvariable"
2271 command to create, and "info tvariables" to view; see "Trace State
2272 Variables" in the manual for more detail.
2276 GDB now includes an option for defining fast tracepoints, which
2277 targets may implement more efficiently, such as by installing a jump
2278 into the target agent rather than a trap instruction. The resulting
2279 speedup can be by two orders of magnitude or more, although the
2280 tradeoff is that some program locations on some target architectures
2281 might not allow fast tracepoint installation, for instance if the
2282 instruction to be replaced is shorter than the jump. To request a
2283 fast tracepoint, use the "ftrace" command, with syntax identical to
2284 the regular trace command.
2286 ** Disconnected tracing
2288 It is now possible to detach GDB from the target while it is running
2289 a trace experiment, then reconnect later to see how the experiment
2290 is going. In addition, a new variable disconnected-tracing lets you
2291 tell the target agent whether to continue running a trace if the
2292 connection is lost unexpectedly.
2296 GDB now has the ability to save the trace buffer into a file, and
2297 then use that file as a target, similarly to you can do with
2298 corefiles. You can select trace frames, print data that was
2299 collected in them, and use tstatus to display the state of the
2300 tracing run at the moment that it was saved. To create a trace
2301 file, use "tsave <filename>", and to use it, do "target tfile
2304 ** Circular trace buffer
2306 You can ask the target agent to handle the trace buffer as a
2307 circular buffer, discarding the oldest trace frames to make room for
2308 newer ones, by setting circular-trace-buffer to on. This feature may
2309 not be available for all target agents.
2314 The disassemble command, when invoked with two arguments, now requires
2315 the arguments to be comma-separated.
2318 The info variables command now displays variable definitions. Files
2319 which only declare a variable are not shown.
2322 The source command is now capable of sourcing Python scripts.
2323 This feature is dependent on the debugger being build with Python
2326 Related to this enhancement is also the introduction of a new command
2327 "set script-extension" (see below).
2329 * New commands (for set/show, see "New options" below)
2331 record save [<FILENAME>]
2332 Save a file (in core file format) containing the process record
2333 execution log for replay debugging at a later time.
2335 record restore <FILENAME>
2336 Restore the process record execution log that was saved at an
2337 earlier time, for replay debugging.
2339 add-inferior [-copies <N>] [-exec <FILENAME>]
2342 clone-inferior [-copies <N>] [ID]
2343 Make a new inferior ready to execute the same program another
2344 inferior has loaded.
2349 maint info program-spaces
2350 List the program spaces loaded into GDB.
2352 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2353 show remote interrupt-sequence
2354 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2355 as the sequence to the remote target in order to interrupt the execution.
2356 Ctrl-C is a default. Some system prefers BREAK which is high level of
2357 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2358 Magic SysRq g. It is BREAK signal and character 'g'.
2360 set remote interrupt-on-connect [on | off]
2361 show remote interrupt-on-connect
2362 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2363 remote target when gdb connects to it. This is needed when you debug
2366 set remotebreak [on | off]
2368 Deprecated. Use "set/show remote interrupt-sequence" instead.
2370 tvariable $NAME [ = EXP ]
2371 Create or modify a trace state variable.
2374 List trace state variables and their values.
2376 delete tvariable $NAME ...
2377 Delete one or more trace state variables.
2380 Evaluate the given expressions without collecting anything into the
2381 trace buffer. (Valid in tracepoint actions only.)
2383 ftrace FN / FILE:LINE / *ADDR
2384 Define a fast tracepoint at the given function, line, or address.
2386 * New expression syntax
2388 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2389 GDB now parses 0b101010 identically with 42.
2393 set follow-exec-mode new|same
2394 show follow-exec-mode
2395 Control whether GDB reuses the same inferior across an exec call or
2396 creates a new one. This is useful to be able to restart the old
2397 executable after the inferior having done an exec call.
2399 set default-collect EXPR, ...
2400 show default-collect
2401 Define a list of expressions to be collected at each tracepoint.
2402 This is a useful way to ensure essential items are not overlooked,
2403 such as registers or a critical global variable.
2405 set disconnected-tracing
2406 show disconnected-tracing
2407 If set to 1, the target is instructed to continue tracing if it
2408 loses its connection to GDB. If 0, the target is to stop tracing
2411 set circular-trace-buffer
2412 show circular-trace-buffer
2413 If set to on, the target is instructed to use a circular trace buffer
2414 and discard the oldest trace frames instead of stopping the trace due
2415 to a full trace buffer. If set to off, the trace stops when the buffer
2416 fills up. Some targets may not support this.
2418 set script-extension off|soft|strict
2419 show script-extension
2420 If set to "off", the debugger does not perform any script language
2421 recognition, and all sourced files are assumed to be GDB scripts.
2422 If set to "soft" (the default), files are sourced according to
2423 filename extension, falling back to GDB scripts if the first
2425 If set to "strict", files are sourced according to filename extension.
2427 set ada trust-PAD-over-XVS on|off
2428 show ada trust-PAD-over-XVS
2429 If off, activate a workaround against a bug in the debugging information
2430 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2431 the GCC sources for more information about the GNAT encoding and
2432 PAD types in particular). It is always safe to set this option to
2433 off, but this introduces a slight performance penalty. The default
2436 * Python API Improvements
2438 ** GDB provides the new class gdb.LazyString. This is useful in
2439 some pretty-printing cases. The new method gdb.Value.lazy_string
2440 provides a simple way to create objects of this type.
2442 ** The fields returned by gdb.Type.fields now have an
2443 `is_base_class' attribute.
2445 ** The new method gdb.Type.range returns the range of an array type.
2447 ** The new method gdb.parse_and_eval can be used to parse and
2448 evaluate an expression.
2450 * New remote packets
2453 Define a trace state variable.
2456 Get the current value of a trace state variable.
2459 Set desired tracing behavior upon disconnection.
2462 Set the trace buffer to be linear or circular.
2465 Get data about the tracepoints currently in use.
2469 Process record now works correctly with hardware watchpoints.
2471 Multiple bug fixes have been made to the mips-irix port, making it
2472 much more reliable. In particular:
2473 - Debugging threaded applications is now possible again. Previously,
2474 GDB would hang while starting the program, or while waiting for
2475 the program to stop at a breakpoint.
2476 - Attaching to a running process no longer hangs.
2477 - An error occurring while loading a core file has been fixed.
2478 - Changing the value of the PC register now works again. This fixes
2479 problems observed when using the "jump" command, or when calling
2480 a function from GDB, or even when assigning a new value to $pc.
2481 - With the "finish" and "return" commands, the return value for functions
2482 returning a small array is now correctly printed.
2483 - It is now possible to break on shared library code which gets executed
2484 during a shared library init phase (code executed while executing
2485 their .init section). Previously, the breakpoint would have no effect.
2486 - GDB is now able to backtrace through the signal handler for
2487 non-threaded programs.
2489 PIE (Position Independent Executable) programs debugging is now supported.
2490 This includes debugging execution of PIC (Position Independent Code) shared
2491 libraries although for that, it should be possible to run such libraries as an
2494 *** Changes in GDB 7.0
2496 * GDB now has an interface for JIT compilation. Applications that
2497 dynamically generate code can create symbol files in memory and register
2498 them with GDB. For users, the feature should work transparently, and
2499 for JIT developers, the interface is documented in the GDB manual in the
2500 "JIT Compilation Interface" chapter.
2502 * Tracepoints may now be conditional. The syntax is as for
2503 breakpoints; either an "if" clause appended to the "trace" command,
2504 or the "condition" command is available. GDB sends the condition to
2505 the target for evaluation using the same bytecode format as is used
2506 for tracepoint actions.
2508 * The disassemble command now supports: an optional /r modifier, print the
2509 raw instructions in hex as well as in symbolic form, and an optional /m
2510 modifier to print mixed source+assembly.
2512 * Process record and replay
2514 In a architecture environment that supports ``process record and
2515 replay'', ``process record and replay'' target can record a log of
2516 the process execution, and replay it with both forward and reverse
2519 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2520 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2521 set execution-direction {forward|reverse}, for targets that support
2524 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2525 feature is available with a native GDB running on kernel version
2528 * GDB now has support for multi-byte and wide character sets on the
2529 target. Strings whose character type is wchar_t, char16_t, or
2530 char32_t are now correctly printed. GDB supports wide- and unicode-
2531 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2532 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2533 `printf'. This feature requires iconv to work properly; if your
2534 system does not have a working iconv, GDB can use GNU libiconv. See
2535 the installation instructions for more information.
2537 * GDB now supports automatic retrieval of shared library files from
2538 remote targets. To use this feature, specify a system root that begins
2539 with the `remote:' prefix, either via the `set sysroot' command or via
2540 the `--with-sysroot' configure-time option.
2542 * "info sharedlibrary" now takes an optional regex of libraries to show,
2543 and it now reports if a shared library has no debugging information.
2545 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2546 now complete on file names.
2548 * When completing in expressions, gdb will attempt to limit
2549 completions to allowable structure or union fields, where appropriate.
2550 For instance, consider:
2552 # struct example { int f1; double f2; };
2553 # struct example variable;
2556 If the user types TAB at the end of this command line, the available
2557 completions will be "f1" and "f2".
2559 * Inlined functions are now supported. They show up in backtraces, and
2560 the "step", "next", and "finish" commands handle them automatically.
2562 * GDB now supports the token-splicing (##) and stringification (#)
2563 operators when expanding macros. It also supports variable-arity
2566 * GDB now supports inspecting extra signal information, exported by
2567 the new $_siginfo convenience variable. The feature is currently
2568 implemented on linux ARM, i386 and amd64.
2570 * GDB can now display the VFP floating point registers and NEON vector
2571 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2572 can provide these registers (requires Linux 2.6.30 or later). Remote
2573 and simulator targets may also provide them.
2575 * New remote packets
2578 Search memory for a sequence of bytes.
2581 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2582 operation over reliable transport links. Use of this packet is
2583 controlled by the `set remote noack-packet' command.
2586 Kill the process with the specified process ID. Use this in preference
2587 to `k' when multiprocess protocol extensions are supported.
2590 Obtains additional operating system information
2594 Read or write additional signal information.
2596 * Removed remote protocol undocumented extension
2598 An undocumented extension to the remote protocol's `S' stop reply
2599 packet that permited the stub to pass a process id was removed.
2600 Remote servers should use the `T' stop reply packet instead.
2602 * GDB now supports multiple function calling conventions according to the
2603 DWARF-2 DW_AT_calling_convention function attribute.
2605 * The SH target utilizes the aforementioned change to distinguish between gcc
2606 and Renesas calling convention. It also adds the new CLI commands
2607 `set/show sh calling-convention'.
2609 * GDB can now read compressed debug sections, as produced by GNU gold
2610 with the --compress-debug-sections=zlib flag.
2612 * 64-bit core files are now supported on AIX.
2614 * Thread switching is now supported on Tru64.
2616 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2617 which will be allocated using malloc later in program execution.
2619 * The qXfer:libraries:read remote procotol packet now allows passing a
2620 list of section offsets.
2622 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2623 conditions handling signals delivered during attach or thread creation
2624 have also been fixed.
2626 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2627 From the user's standpoint, all unqualified instances of True and False
2628 are treated as the standard definitions, regardless of context.
2630 * GDB now parses C++ symbol and type names more flexibly. For
2633 template<typename T> class C { };
2636 GDB will now correctly handle all of:
2638 ptype C<char const *>
2639 ptype C<char const*>
2640 ptype C<const char *>
2641 ptype C<const char*>
2643 * New features in the GDB remote stub, gdbserver
2645 - The "--wrapper" command-line argument tells gdbserver to use a
2646 wrapper program to launch programs for debugging.
2648 - On PowerPC and S/390 targets, it is now possible to use a single
2649 gdbserver executable to debug both 32-bit and 64-bit programs.
2650 (This requires gdbserver itself to be built as a 64-bit executable.)
2652 - gdbserver uses the new noack protocol mode for TCP connections to
2653 reduce communications latency, if also supported and enabled in GDB.
2655 - Support for the sparc64-linux-gnu target is now included in
2658 - The amd64-linux build of gdbserver now supports debugging both
2659 32-bit and 64-bit programs.
2661 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2662 now support hardware watchpoints, and will use them automatically
2667 GDB now has support for scripting using Python. Whether this is
2668 available is determined at configure time.
2670 New GDB commands can now be written in Python.
2672 * Ada tasking support
2674 Ada tasks can now be inspected in GDB. The following commands have
2678 Print the list of Ada tasks.
2680 Print detailed information about task number N.
2682 Print the task number of the current task.
2684 Switch the context of debugging to task number N.
2686 * Support for user-defined prefixed commands. The "define" command can
2687 add new commands to existing prefixes, e.g. "target".
2689 * Multi-inferior, multi-process debugging.
2691 GDB now has generalized support for multi-inferior debugging. See
2692 "Debugging Multiple Inferiors" in the manual for more information.
2693 Although availability still depends on target support, the command
2694 set is more uniform now. The GNU/Linux specific multi-forks support
2695 has been migrated to this new framework. This implied some user
2696 visible changes; see "New commands" and also "Removed commands"
2699 * Target descriptions can now describe the target OS ABI. See the
2700 "Target Description Format" section in the user manual for more
2703 * Target descriptions can now describe "compatible" architectures
2704 to indicate that the target can execute applications for a different
2705 architecture in addition to those for the main target architecture.
2706 See the "Target Description Format" section in the user manual for
2709 * Multi-architecture debugging.
2711 GDB now includes general supports for debugging applications on
2712 hybrid systems that use more than one single processor architecture
2713 at the same time. Each such hybrid architecture still requires
2714 specific support to be added. The only hybrid architecture supported
2715 in this version of GDB is the Cell Broadband Engine.
2717 * GDB now supports integrated debugging of Cell/B.E. applications that
2718 use both the PPU and SPU architectures. To enable support for hybrid
2719 Cell/B.E. debugging, you need to configure GDB to support both the
2720 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2721 --enable-targets configure option.
2723 * Non-stop mode debugging.
2725 For some targets, GDB now supports an optional mode of operation in
2726 which you can examine stopped threads while other threads continue
2727 to execute freely. This is referred to as non-stop mode, with the
2728 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2729 section in the user manual for more information.
2731 To be able to support remote non-stop debugging, a remote stub needs
2732 to implement the non-stop mode remote protocol extensions, as
2733 described in the "Remote Non-Stop" section of the user manual. The
2734 GDB remote stub, gdbserver, has been adjusted to support these
2735 extensions on linux targets.
2737 * New commands (for set/show, see "New options" below)
2739 catch syscall [NAME(S) | NUMBER(S)]
2740 Catch system calls. Arguments, which should be names of system
2741 calls or their numbers, mean catch only those syscalls. Without
2742 arguments, every syscall will be caught. When the inferior issues
2743 any of the specified syscalls, GDB will stop and announce the system
2744 call, both when it is called and when its call returns. This
2745 feature is currently available with a native GDB running on the
2746 Linux Kernel, under the following architectures: x86, x86_64,
2747 PowerPC and PowerPC64.
2749 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2751 Search memory for a sequence of bytes.
2753 maint set python print-stack
2754 maint show python print-stack
2755 Show a stack trace when an error is encountered in a Python script.
2758 Invoke CODE by passing it to the Python interpreter.
2763 These allow macros to be defined, undefined, and listed
2767 Show operating system information about processes.
2770 List the inferiors currently under GDB's control.
2773 Switch focus to inferior number NUM.
2776 Detach from inferior number NUM.
2779 Kill inferior number NUM.
2783 set spu stop-on-load
2784 show spu stop-on-load
2785 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2787 set spu auto-flush-cache
2788 show spu auto-flush-cache
2789 Control whether to automatically flush the software-managed cache
2790 during Cell/B.E. debugging.
2792 set sh calling-convention
2793 show sh calling-convention
2794 Control the calling convention used when calling SH target functions.
2797 show debug timestamp
2798 Control display of timestamps with GDB debugging output.
2800 set disassemble-next-line
2801 show disassemble-next-line
2802 Control display of disassembled source lines or instructions when
2805 set remote noack-packet
2806 show remote noack-packet
2807 Set/show the use of remote protocol QStartNoAckMode packet. See above
2808 under "New remote packets."
2810 set remote query-attached-packet
2811 show remote query-attached-packet
2812 Control use of remote protocol `qAttached' (query-attached) packet.
2814 set remote read-siginfo-object
2815 show remote read-siginfo-object
2816 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2819 set remote write-siginfo-object
2820 show remote write-siginfo-object
2821 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2824 set remote reverse-continue
2825 show remote reverse-continue
2826 Control use of remote protocol 'bc' (reverse-continue) packet.
2828 set remote reverse-step
2829 show remote reverse-step
2830 Control use of remote protocol 'bs' (reverse-step) packet.
2832 set displaced-stepping
2833 show displaced-stepping
2834 Control displaced stepping mode. Displaced stepping is a way to
2835 single-step over breakpoints without removing them from the debuggee.
2836 Also known as "out-of-line single-stepping".
2839 show debug displaced
2840 Control display of debugging info for displaced stepping.
2842 maint set internal-error
2843 maint show internal-error
2844 Control what GDB does when an internal error is detected.
2846 maint set internal-warning
2847 maint show internal-warning
2848 Control what GDB does when an internal warning is detected.
2853 Use a wrapper program to launch programs for debugging.
2855 set multiple-symbols (all|ask|cancel)
2856 show multiple-symbols
2857 The value of this variable can be changed to adjust the debugger behavior
2858 when an expression or a breakpoint location contains an ambiguous symbol
2859 name (an overloaded function name, for instance).
2861 set breakpoint always-inserted
2862 show breakpoint always-inserted
2863 Keep breakpoints always inserted in the target, as opposed to inserting
2864 them when resuming the target, and removing them when the target stops.
2865 This option can improve debugger performance on slow remote targets.
2867 set arm fallback-mode (arm|thumb|auto)
2868 show arm fallback-mode
2869 set arm force-mode (arm|thumb|auto)
2871 These commands control how ARM GDB determines whether instructions
2872 are ARM or Thumb. The default for both settings is auto, which uses
2873 the current CPSR value for instructions without symbols; previous
2874 versions of GDB behaved as if "set arm fallback-mode arm".
2876 set disable-randomization
2877 show disable-randomization
2878 Standalone programs run with the virtual address space randomization enabled
2879 by default on some platforms. This option keeps the addresses stable across
2880 multiple debugging sessions.
2884 Control whether other threads are stopped or not when some thread hits
2889 Requests that asynchronous execution is enabled in the target, if available.
2890 In this case, it's possible to resume target in the background, and interact
2891 with GDB while the target is running. "show target-async" displays the
2892 current state of asynchronous execution of the target.
2894 set target-wide-charset
2895 show target-wide-charset
2896 The target-wide-charset is the name of the character set that GDB
2897 uses when printing characters whose type is wchar_t.
2899 set tcp auto-retry (on|off)
2901 set tcp connect-timeout
2902 show tcp connect-timeout
2903 These commands allow GDB to retry failed TCP connections to a remote stub
2904 with a specified timeout period; this is useful if the stub is launched
2905 in parallel with GDB but may not be ready to accept connections immediately.
2907 set libthread-db-search-path
2908 show libthread-db-search-path
2909 Control list of directories which GDB will search for appropriate
2912 set schedule-multiple (on|off)
2913 show schedule-multiple
2914 Allow GDB to resume all threads of all processes or only threads of
2915 the current process.
2919 Use more aggressive caching for accesses to the stack. This improves
2920 performance of remote debugging (particularly backtraces) without
2921 affecting correctness.
2923 set interactive-mode (on|off|auto)
2924 show interactive-mode
2925 Control whether GDB runs in interactive mode (on) or not (off).
2926 When in interactive mode, GDB waits for the user to answer all
2927 queries. Otherwise, GDB does not wait and assumes the default
2928 answer. When set to auto (the default), GDB determines which
2929 mode to use based on the stdin settings.
2934 For program forks, this is replaced by the new more generic `info
2935 inferiors' command. To list checkpoints, you can still use the
2936 `info checkpoints' command, which was an alias for the `info forks'
2940 Replaced by the new `inferior' command. To switch between
2941 checkpoints, you can still use the `restart' command, which was an
2942 alias for the `fork' command.
2945 This is removed, since some targets don't have a notion of
2946 processes. To switch between processes, you can still use the
2947 `inferior' command using GDB's own inferior number.
2950 For program forks, this is replaced by the new more generic `kill
2951 inferior' command. To delete a checkpoint, you can still use the
2952 `delete checkpoint' command, which was an alias for the `delete
2956 For program forks, this is replaced by the new more generic `detach
2957 inferior' command. To detach a checkpoint, you can still use the
2958 `detach checkpoint' command, which was an alias for the `detach
2961 * New native configurations
2963 x86/x86_64 Darwin i[34567]86-*-darwin*
2965 x86_64 MinGW x86_64-*-mingw*
2969 Lattice Mico32 lm32-*
2970 x86 DICOS i[34567]86-*-dicos*
2971 x86_64 DICOS x86_64-*-dicos*
2974 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2975 (mingw32ce) debugging.
2981 These commands were actually not implemented on any target.
2983 *** Changes in GDB 6.8
2985 * New native configurations
2987 NetBSD/hppa hppa*-*netbsd*
2988 Xtensa GNU/Linux xtensa*-*-linux*
2992 NetBSD/hppa hppa*-*-netbsd*
2993 Xtensa GNU/Lunux xtensa*-*-linux*
2995 * Change in command line behavior -- corefiles vs. process ids.
2997 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2998 attaching to process NUMBER fails, GDB no longer attempts to open a
2999 core file named NUMBER. Attaching to a program using the -c option
3000 is no longer supported. Instead, use the '-p' or '--pid' options.
3002 * GDB can now be built as a native debugger for debugging Windows x86
3003 (mingw32) Portable Executable (PE) programs.
3005 * Pending breakpoints no longer change their number when their address
3008 * GDB now supports breakpoints with multiple locations,
3009 including breakpoints on C++ constructors, inside C++ templates,
3010 and in inlined functions.
3012 * GDB's ability to debug optimized code has been improved. GDB more
3013 accurately identifies function bodies and lexical blocks that occupy
3014 more than one contiguous range of addresses.
3016 * Target descriptions can now describe registers for PowerPC.
3018 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3019 registers on PowerPC targets.
3021 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3022 targets even when the libthread_db library is not available.
3024 * The GDB remote stub, gdbserver, now supports the new file transfer
3025 commands (remote put, remote get, and remote delete).
3027 * The GDB remote stub, gdbserver, now supports run and attach in
3028 extended-remote mode.
3030 * hppa*64*-*-hpux11* target broken
3031 The debugger is unable to start a program and fails with the following
3032 error: "Error trying to get information about dynamic linker".
3033 The gdb-6.7 release is also affected.
3035 * GDB now supports the --enable-targets= configure option to allow
3036 building a single GDB executable that supports multiple remote
3037 target architectures.
3039 * GDB now supports debugging C and C++ programs which use the
3040 Decimal Floating Point extension. In addition, the PowerPC target
3041 now has a set of pseudo-registers to inspect decimal float values
3042 stored in two consecutive float registers.
3044 * The -break-insert MI command can optionally create pending
3047 * Improved support for debugging Ada
3048 Many improvements to the Ada language support have been made. These
3050 - Better support for Ada2005 interface types
3051 - Improved handling of arrays and slices in general
3052 - Better support for Taft-amendment types
3053 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3055 - Improved command completion in Ada
3058 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3063 set print frame-arguments (all|scalars|none)
3064 show print frame-arguments
3065 The value of this variable can be changed to control which argument
3066 values should be printed by the debugger when displaying a frame.
3071 Transfer files to and from a remote target, and delete remote files.
3078 Transfer files to and from a remote target, and delete remote files.
3080 * New remote packets
3087 Open, close, read, write, and delete files on the remote system.
3090 Attach to an existing process on the remote system, in extended-remote
3094 Run a new process on the remote system, in extended-remote mode.
3096 *** Changes in GDB 6.7
3098 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3099 bfd, libiberty and opcodes, as revealed by static analysis donated by
3100 Coverity, Inc. (http://scan.coverity.com).
3102 * When looking up multiply-defined global symbols, GDB will now prefer the
3103 symbol definition in the current shared library if it was built using the
3104 -Bsymbolic linker option.
3106 * When the Text User Interface (TUI) is not configured, GDB will now
3107 recognize the -tui command-line option and print a message that the TUI
3110 * The GDB remote stub, gdbserver, now has lower overhead for high
3111 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3113 * GDB for MIPS targets now autodetects whether a remote target provides
3114 32-bit or 64-bit register values.
3116 * Support for C++ member pointers has been improved.
3118 * GDB now understands XML target descriptions, which specify the
3119 target's overall architecture. GDB can read a description from
3120 a local file or over the remote serial protocol.
3122 * Vectors of single-byte data use a new integer type which is not
3123 automatically displayed as character or string data.
3125 * The /s format now works with the print command. It displays
3126 arrays of single-byte integers and pointers to single-byte integers
3129 * Target descriptions can now describe target-specific registers,
3130 for architectures which have implemented the support (currently
3131 only ARM, M68K, and MIPS).
3133 * GDB and the GDB remote stub, gdbserver, now support the XScale
3136 * The GDB remote stub, gdbserver, has been updated to support
3137 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3138 has been rewritten to use the standard GDB remote protocol.
3140 * GDB can now step into C++ functions which are called through thunks.
3142 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3144 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3145 layout. It also supports a TextSeg= and DataSeg= response when only
3146 segment base addresses (rather than offsets) are available.
3148 * The /i format now outputs any trailing branch delay slot instructions
3149 immediately following the last instruction within the count specified.
3151 * The GDB remote protocol "T" stop reply packet now supports a
3152 "library" response. Combined with the new "qXfer:libraries:read"
3153 packet, this response allows GDB to debug shared libraries on targets
3154 where the operating system manages the list of loaded libraries (e.g.
3155 Windows and SymbianOS).
3157 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3158 (DLLs) on Windows and Windows CE targets.
3160 * GDB now supports a faster verification that a .debug file matches its binary
3161 according to its build-id signature, if the signature is present.
3167 Enable or disable hardware flow control (RTS/CTS) on the serial port
3168 when debugging using remote targets.
3170 set mem inaccessible-by-default
3171 show mem inaccessible-by-default
3172 If the target supplies a memory map, for instance via the remote
3173 protocol's "qXfer:memory-map:read" packet, setting this variable
3174 prevents GDB from accessing memory outside the memory map. This
3175 is useful for targets with memory mapped registers or which react
3176 badly to accesses of unmapped address space.
3178 set breakpoint auto-hw
3179 show breakpoint auto-hw
3180 If the target supplies a memory map, for instance via the remote
3181 protocol's "qXfer:memory-map:read" packet, setting this variable
3182 lets GDB use hardware breakpoints automatically for memory regions
3183 where it can not use software breakpoints. This covers both the
3184 "break" command and internal breakpoints used for other commands
3185 including "next" and "finish".
3188 catch exception unhandled
3189 Stop the program execution when Ada exceptions are raised.
3192 Stop the program execution when an Ada assertion failed.
3196 Set an alternate system root for target files. This is a more
3197 general version of "set solib-absolute-prefix", which is now
3198 an alias to "set sysroot".
3201 Provide extended SPU facility status information. This set of
3202 commands is available only when debugging the Cell/B.E. SPU
3205 * New native configurations
3207 OpenBSD/sh sh*-*openbsd*
3210 unset tdesc filename
3212 Use the specified local file as an XML target description, and do
3213 not query the target for its built-in description.
3217 OpenBSD/sh sh*-*-openbsd*
3218 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3219 Toshiba Media Processor mep-elf
3221 * New remote packets
3224 Ignore the specified signals; pass them directly to the debugged program
3225 without stopping other threads or reporting them to GDB.
3227 qXfer:features:read:
3228 Read an XML target description from the target, which describes its
3233 Read or write contents of an spufs file on the target system. These
3234 packets are available only on the Cell/B.E. SPU architecture.
3236 qXfer:libraries:read:
3237 Report the loaded shared libraries. Combined with new "T" packet
3238 response, this packet allows GDB to debug shared libraries on
3239 targets where the operating system manages the list of loaded
3240 libraries (e.g. Windows and SymbianOS).
3244 Support for these obsolete configurations has been removed.
3252 i[34567]86-*-lynxos*
3253 i[34567]86-*-netware*
3254 i[34567]86-*-sco3.2v5*
3255 i[34567]86-*-sco3.2v4*
3257 i[34567]86-*-sysv4.2*
3260 i[34567]86-*-unixware2*
3261 i[34567]86-*-unixware*
3270 * Other removed features
3277 Various m68k-only ROM monitors.
3284 Various Renesas ROM monitors and debugging interfaces for SH and
3289 Support for a Macraigor serial interface to on-chip debugging.
3290 GDB does not directly support the newer parallel or USB
3295 A debug information format. The predecessor to DWARF 2 and
3296 DWARF 3, which are still supported.
3298 Support for the HP aCC compiler on HP-UX/PA-RISC
3300 SOM-encapsulated symbolic debugging information, automatic
3301 invocation of pxdb, and the aCC custom C++ ABI. This does not
3302 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3303 with aCC can still be debugged on an assembly level.
3305 MIPS ".pdr" sections
3307 A MIPS-specific format used to describe stack frame layout
3308 in debugging information.
3312 GDB could work with an older version of Guile to debug
3313 the interpreter and Scheme programs running in it.
3315 set mips stack-arg-size
3316 set mips saved-gpreg-size
3318 Use "set mips abi" to control parameter passing for MIPS.
3320 *** Changes in GDB 6.6
3325 Cell Broadband Engine SPU spu-elf
3327 * GDB can now be configured as a cross-debugger targeting native Windows
3328 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3329 running on a Windows system over TCP/IP to debug Windows programs.
3331 * The GDB remote stub, gdbserver, has been updated to support Windows and
3332 Cygwin debugging. Both single-threaded and multi-threaded programs are
3335 * The "set trust-readonly-sections" command works again. This command was
3336 broken in GDB 6.3, 6.4, and 6.5.
3338 * The "load" command now supports writing to flash memory, if the remote
3339 stub provides the required support.
3341 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3342 longer requires symbolic debug information (e.g. DWARF-2).
3347 unset substitute-path
3348 show substitute-path
3349 Manage a list of substitution rules that GDB uses to rewrite the name
3350 of the directories where the sources are located. This can be useful
3351 for instance when the sources were moved to a different location
3352 between compilation and debugging.
3356 Print each CLI command as it is executed. Each command is prefixed with
3357 a number of `+' symbols representing the nesting depth.
3358 The source command now has a `-v' option to enable the same feature.
3362 The ARM Demon monitor support (RDP protocol, "target rdp").
3364 Kernel Object Display, an embedded debugging feature which only worked with
3365 an obsolete version of Cisco IOS.
3367 The 'set download-write-size' and 'show download-write-size' commands.
3369 * New remote packets
3372 Tell a stub about GDB client features, and request remote target features.
3373 The first feature implemented is PacketSize, which allows the target to
3374 specify the size of packets it can handle - to minimize the number of
3375 packets required and improve performance when connected to a remote
3379 Fetch an OS auxilliary vector from the remote stub. This packet is a
3380 more efficient replacement for qPart:auxv:read.
3382 qXfer:memory-map:read:
3383 Fetch a memory map from the remote stub, including information about
3384 RAM, ROM, and flash memory devices.
3389 Erase and program a flash memory device.
3391 * Removed remote packets
3394 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3395 used it, and only gdbserver implemented it.
3397 *** Changes in GDB 6.5
3401 Renesas M32C/M16C m32c-elf
3403 Morpho Technologies ms1 ms1-elf
3407 init-if-undefined Initialize a convenience variable, but
3408 only if it doesn't already have a value.
3410 The following commands are presently only implemented for native GNU/Linux:
3412 checkpoint Save a snapshot of the program state.
3414 restart <n> Return the program state to a
3415 previously saved state.
3417 info checkpoints List currently saved checkpoints.
3419 delete-checkpoint <n> Delete a previously saved checkpoint.
3421 set|show detach-on-fork Tell gdb whether to detach from a newly
3422 forked process, or to keep debugging it.
3424 info forks List forks of the user program that
3425 are available to be debugged.
3427 fork <n> Switch to debugging one of several
3428 forks of the user program that are
3429 available to be debugged.
3431 delete-fork <n> Delete a fork from the list of forks
3432 that are available to be debugged (and
3433 kill the forked process).
3435 detach-fork <n> Delete a fork from the list of forks
3436 that are available to be debugged (and
3437 allow the process to continue).
3441 Morpho Technologies ms2 ms1-elf
3443 * Improved Windows host support
3445 GDB now builds as a cross debugger hosted on i686-mingw32, including
3446 native console support, and remote communications using either
3447 network sockets or serial ports.
3449 * Improved Modula-2 language support
3451 GDB can now print most types in the Modula-2 syntax. This includes:
3452 basic types, set types, record types, enumerated types, range types,
3453 pointer types and ARRAY types. Procedure var parameters are correctly
3454 printed and hexadecimal addresses and character constants are also
3455 written in the Modula-2 syntax. Best results can be obtained by using
3456 GNU Modula-2 together with the -gdwarf-2 command line option.
3460 The ARM rdi-share module.
3462 The Netware NLM debug server.
3464 *** Changes in GDB 6.4
3466 * New native configurations
3468 OpenBSD/arm arm*-*-openbsd*
3469 OpenBSD/mips64 mips64-*-openbsd*
3473 Morpho Technologies ms1 ms1-elf
3475 * New command line options
3477 --batch-silent As for --batch, but totally silent.
3478 --return-child-result The debugger will exist with the same value
3479 the child (debugged) program exited with.
3480 --eval-command COMMAND, -ex COMMAND
3481 Execute a single GDB CLI command. This may be
3482 specified multiple times and in conjunction
3483 with the --command (-x) option.
3485 * Deprecated commands removed
3487 The following commands, that were deprecated in 2000, have been
3491 set|show arm disassembly-flavor set|show arm disassembler
3492 othernames set arm disassembler
3493 set|show remotedebug set|show debug remote
3494 set|show archdebug set|show debug arch
3495 set|show eventdebug set|show debug event
3498 * New BSD user-level threads support
3500 It is now possible to debug programs using the user-level threads
3501 library on OpenBSD and FreeBSD. Currently supported (target)
3504 FreeBSD/amd64 x86_64-*-freebsd*
3505 FreeBSD/i386 i386-*-freebsd*
3506 OpenBSD/i386 i386-*-openbsd*
3508 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3509 are not yet supported.
3511 * New support for Matsushita MN10300 w/sim added
3512 (Work in progress). mn10300-elf.
3514 * REMOVED configurations and files
3516 VxWorks and the XDR protocol *-*-vxworks
3517 Motorola MCORE mcore-*-*
3518 National Semiconductor NS32000 ns32k-*-*
3520 * New "set print array-indexes" command
3522 After turning this setting "on", GDB prints the index of each element
3523 when displaying arrays. The default is "off" to preserve the previous
3526 * VAX floating point support
3528 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3530 * User-defined command support
3532 In addition to using $arg0..$arg9 for argument passing, it is now possible
3533 to use $argc to determine now many arguments have been passed. See the
3534 section on user-defined commands in the user manual for more information.
3536 *** Changes in GDB 6.3:
3538 * New command line option
3540 GDB now accepts -l followed by a number to set the timeout for remote
3543 * GDB works with GCC -feliminate-dwarf2-dups
3545 GDB now supports a more compact representation of DWARF-2 debug
3546 information using DW_FORM_ref_addr references. These are produced
3547 by GCC with the option -feliminate-dwarf2-dups and also by some
3548 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3549 to use -feliminate-dwarf2-dups.
3551 * Internationalization
3553 When supported by the host system, GDB will be built with
3554 internationalization (libintl). The task of marking up the sources is
3555 continued, we're looking forward to our first translation.
3559 Initial support for debugging programs compiled with the GNAT
3560 implementation of the Ada programming language has been integrated
3561 into GDB. In this release, support is limited to expression evaluation.
3563 * New native configurations
3565 GNU/Linux/m32r m32r-*-linux-gnu
3569 GDB's remote protocol now includes support for the 'p' packet. This
3570 packet is used to fetch individual registers from a remote inferior.
3572 * END-OF-LIFE registers[] compatibility module
3574 GDB's internal register infrastructure has been completely rewritten.
3575 The new infrastructure making possible the implementation of key new
3576 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3579 GDB 6.3 will be the last release to include the the registers[]
3580 compatibility module that allowed out-of-date configurations to
3581 continue to work. This change directly impacts the following
3591 powerpc bdm protocol
3593 Unless there is activity to revive these configurations, they will be
3594 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3596 * OBSOLETE configurations and files
3598 Configurations that have been declared obsolete in this release have
3599 been commented out. Unless there is activity to revive these
3600 configurations, the next release of GDB will have their sources
3601 permanently REMOVED.
3610 *** Changes in GDB 6.2.1:
3612 * MIPS `break main; run' gave an heuristic-fence-post warning
3614 When attempting to run even a simple program, a warning about
3615 heuristic-fence-post being hit would be reported. This problem has
3618 * MIPS IRIX 'long double' crashed GDB
3620 When examining a long double variable, GDB would get a segmentation
3621 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3622 IRIX long double values).
3626 A bug in the VAX stack code was causing problems with the "next"
3627 command. This problem has been fixed.
3629 *** Changes in GDB 6.2:
3631 * Fix for ``many threads''
3633 On GNU/Linux systems that use the NPTL threads library, a program
3634 rapidly creating and deleting threads would confuse GDB leading to the
3637 ptrace: No such process.
3638 thread_db_get_info: cannot get thread info: generic error
3640 This problem has been fixed.
3642 * "-async" and "-noasync" options removed.
3644 Support for the broken "-noasync" option has been removed (it caused
3647 * New ``start'' command.
3649 This command runs the program until the begining of the main procedure.
3651 * New BSD Kernel Data Access Library (libkvm) interface
3653 Using ``target kvm'' it is now possible to debug kernel core dumps and
3654 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3655 platforms. Currently supported (native-only) configurations are:
3657 FreeBSD/amd64 x86_64-*-freebsd*
3658 FreeBSD/i386 i?86-*-freebsd*
3659 NetBSD/i386 i?86-*-netbsd*
3660 NetBSD/m68k m68*-*-netbsd*
3661 NetBSD/sparc sparc-*-netbsd*
3662 OpenBSD/amd64 x86_64-*-openbsd*
3663 OpenBSD/i386 i?86-*-openbsd*
3664 OpenBSD/m68k m68*-openbsd*
3665 OpenBSD/sparc sparc-*-openbsd*
3667 * Signal trampoline code overhauled
3669 Many generic problems with GDB's signal handling code have been fixed.
3670 These include: backtraces through non-contiguous stacks; recognition
3671 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3672 call; backtrace through a signal trampoline; step into and out of
3673 signal handlers; and single-stepping in the signal trampoline.
3675 Please note that kernel bugs are a limiting factor here. These
3676 features have been shown to work on an s390 GNU/Linux system that
3677 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3679 * Cygwin support for DWARF 2 added.
3681 * New native configurations
3683 GNU/Linux/hppa hppa*-*-linux*
3684 OpenBSD/hppa hppa*-*-openbsd*
3685 OpenBSD/m68k m68*-*-openbsd*
3686 OpenBSD/m88k m88*-*-openbsd*
3687 OpenBSD/powerpc powerpc-*-openbsd*
3688 NetBSD/vax vax-*-netbsd*
3689 OpenBSD/vax vax-*-openbsd*
3691 * END-OF-LIFE frame compatibility module
3693 GDB's internal frame infrastructure has been completely rewritten.
3694 The new infrastructure making it possible to support key new features
3695 including DWARF 2 Call Frame Information. To aid in the task of
3696 migrating old configurations to this new infrastructure, a
3697 compatibility module, that allowed old configurations to continue to
3698 work, was also included.
3700 GDB 6.2 will be the last release to include this frame compatibility
3701 module. This change directly impacts the following configurations:
3711 Unless there is activity to revive these configurations, they will be
3712 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3714 * REMOVED configurations and files
3716 Sun 3, running SunOS 3 m68*-*-sunos3*
3717 Sun 3, running SunOS 4 m68*-*-sunos4*
3718 Sun 2, running SunOS 3 m68000-*-sunos3*
3719 Sun 2, running SunOS 4 m68000-*-sunos4*
3720 Motorola 680x0 running LynxOS m68*-*-lynxos*
3721 AT&T 3b1/Unix pc m68*-att-*
3722 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3723 decstation mips-dec-* mips-little-*
3724 riscos mips-*-riscos* mips-*-sysv*
3725 sonymips mips-sony-*
3726 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3728 *** Changes in GDB 6.1.1:
3730 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3732 The TUI (Text-mode User Interface) is now built as part of a default
3733 GDB configuration. It is enabled by either selecting the TUI with the
3734 command line option "-i=tui" or by running the separate "gdbtui"
3735 program. For more information on the TUI, see the manual "Debugging
3738 * Pending breakpoint support (also included in GDB 6.1)
3740 Support has been added to allow you to specify breakpoints in shared
3741 libraries that have not yet been loaded. If a breakpoint location
3742 cannot be found, and the "breakpoint pending" option is set to auto,
3743 GDB queries you if you wish to make the breakpoint pending on a future
3744 shared-library load. If and when GDB resolves the breakpoint symbol,
3745 the pending breakpoint is removed as one or more regular breakpoints
3748 Pending breakpoints are very useful for GCJ Java debugging.
3750 * Fixed ISO-C build problems
3752 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3753 non ISO-C code that stopped them being built using a more strict ISO-C
3754 compiler (e.g., IBM's C compiler).
3756 * Fixed build problem on IRIX 5
3758 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3759 wasn't able to compile compile on an IRIX 5 system.
3761 * Added execute permission to gdb/gdbserver/configure
3763 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3764 permission. This bug would cause configure to fail on a number of
3765 systems (Solaris, IRIX). Ref: server/519.
3767 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3769 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3770 has been updated to use constant array sizes.
3772 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3774 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3775 its generated DWARF Call Frame Info. This encoding was causing GDB to
3776 panic, that panic has been fixed. Ref: gdb/1628.
3778 * Fixed a problem when examining parameters in shared library code.
3780 When examining parameters in optimized shared library code generated
3781 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3782 not available''. GDB now correctly displays the variable's value.
3784 *** Changes in GDB 6.1:
3786 * Removed --with-mmalloc
3788 Support for the mmalloc memory manager has been removed, as it
3789 conflicted with the internal gdb byte cache.
3791 * Changes in AMD64 configurations
3793 The AMD64 target now includes the %cs and %ss registers. As a result
3794 the AMD64 remote protocol has changed; this affects the floating-point
3795 and SSE registers. If you rely on those registers for your debugging,
3796 you should upgrade gdbserver on the remote side.
3798 * Revised SPARC target
3800 The SPARC target has been completely revised, incorporating the
3801 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3802 support for LynxOS and SunOS 4 has been dropped. Calling functions
3803 from within GDB on operating systems with a non-executable stack
3804 (Solaris, OpenBSD) now works.
3808 GDB has a new C++ demangler which does a better job on the mangled
3809 names generated by current versions of g++. It also runs faster, so
3810 with this and other changes gdb should now start faster on large C++
3813 * DWARF 2 Location Expressions
3815 GDB support for location expressions has been extended to support function
3816 arguments and frame bases. Older versions of GDB could crash when they
3819 * C++ nested types and namespaces
3821 GDB's support for nested types and namespaces in C++ has been
3822 improved, especially if you use the DWARF 2 debugging format. (This
3823 is the default for recent versions of GCC on most platforms.)
3824 Specifically, if you have a class "Inner" defined within a class or
3825 namespace "Outer", then GDB realizes that the class's name is
3826 "Outer::Inner", not simply "Inner". This should greatly reduce the
3827 frequency of complaints about not finding RTTI symbols. In addition,
3828 if you are stopped at inside of a function defined within a namespace,
3829 GDB modifies its name lookup accordingly.
3831 * New native configurations
3833 NetBSD/amd64 x86_64-*-netbsd*
3834 OpenBSD/amd64 x86_64-*-openbsd*
3835 OpenBSD/alpha alpha*-*-openbsd*
3836 OpenBSD/sparc sparc-*-openbsd*
3837 OpenBSD/sparc64 sparc64-*-openbsd*
3839 * New debugging protocols
3841 M32R with SDI protocol m32r-*-elf*
3843 * "set prompt-escape-char" command deleted.
3845 The command "set prompt-escape-char" has been deleted. This command,
3846 and its very obscure effet on GDB's prompt, was never documented,
3847 tested, nor mentioned in the NEWS file.
3849 * OBSOLETE configurations and files
3851 Configurations that have been declared obsolete in this release have
3852 been commented out. Unless there is activity to revive these
3853 configurations, the next release of GDB will have their sources
3854 permanently REMOVED.
3856 Sun 3, running SunOS 3 m68*-*-sunos3*
3857 Sun 3, running SunOS 4 m68*-*-sunos4*
3858 Sun 2, running SunOS 3 m68000-*-sunos3*
3859 Sun 2, running SunOS 4 m68000-*-sunos4*
3860 Motorola 680x0 running LynxOS m68*-*-lynxos*
3861 AT&T 3b1/Unix pc m68*-att-*
3862 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3863 decstation mips-dec-* mips-little-*
3864 riscos mips-*-riscos* mips-*-sysv*
3865 sonymips mips-sony-*
3866 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3868 * REMOVED configurations and files
3870 SGI Irix-4.x mips-sgi-irix4 or iris4
3871 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3872 Z8000 simulator z8k-zilog-none or z8ksim
3873 Matsushita MN10200 w/simulator mn10200-*-*
3874 H8/500 simulator h8500-hitachi-hms or h8500hms
3875 HP/PA running BSD hppa*-*-bsd*
3876 HP/PA running OSF/1 hppa*-*-osf*
3877 HP/PA Pro target hppa*-*-pro*
3878 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3879 386BSD i[3456]86-*-bsd*
3880 Sequent family i[3456]86-sequent-sysv4*
3881 i[3456]86-sequent-sysv*
3882 i[3456]86-sequent-bsd*
3883 SPARC running LynxOS sparc-*-lynxos*
3884 SPARC running SunOS 4 sparc-*-sunos4*
3885 Tsqware Sparclet sparclet-*-*
3886 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3888 *** Changes in GDB 6.0:
3892 Support for debugging the Objective-C programming language has been
3893 integrated into GDB.
3895 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3897 DWARF 2's Call Frame Information makes available compiler generated
3898 information that more exactly describes the program's run-time stack.
3899 By using this information, GDB is able to provide more robust stack
3902 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3903 have been updated to use a new backtrace mechanism which includes
3904 DWARF 2 CFI support.
3908 GDB's remote protocol has been extended to include support for hosted
3909 file I/O (where the remote target uses GDB's file system). See GDB's
3910 remote protocol documentation for details.
3912 * All targets using the new architecture framework.
3914 All of GDB's targets have been updated to use the new internal
3915 architecture framework. The way is now open for future GDB releases
3916 to include cross-architecture native debugging support (i386 on amd64,
3919 * GNU/Linux's Thread Local Storage (TLS)
3921 GDB now includes support for for the GNU/Linux implementation of
3922 per-thread variables.
3924 * GNU/Linux's Native POSIX Thread Library (NPTL)
3926 GDB's thread code has been updated to work with either the new
3927 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3929 * Separate debug info.
3931 GDB, in conjunction with BINUTILS, now supports a mechanism for
3932 automatically loading debug information from a separate file. Instead
3933 of shipping full debug and non-debug versions of system libraries,
3934 system integrators can now instead ship just the stripped libraries
3935 and optional debug files.
3937 * DWARF 2 Location Expressions
3939 DWARF 2 Location Expressions allow the compiler to more completely
3940 describe the location of variables (even in optimized code) to the
3943 GDB now includes preliminary support for location expressions (support
3944 for DW_OP_piece is still missing).
3948 A number of long standing bugs that caused GDB to die while starting a
3949 Java application have been fixed. GDB's Java support is now
3950 considered "useable".
3952 * GNU/Linux support for fork, vfork, and exec.
3954 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3955 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3958 * GDB supports logging output to a file
3960 There are two new commands, "set logging" and "show logging", which can be
3961 used to capture GDB's output to a file.
3963 * The meaning of "detach" has changed for gdbserver
3965 The "detach" command will now resume the application, as documented. To
3966 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3969 * d10v, m68hc11 `regs' command deprecated
3971 The `info registers' command has been updated so that it displays the
3972 registers using a format identical to the old `regs' command.
3976 A new command, "maint set profile on/off", has been added. This command can
3977 be used to enable or disable profiling while running GDB, to profile a
3978 session or a set of commands. In addition there is a new configure switch,
3979 "--enable-profiling", which will cause GDB to be compiled with profiling
3980 data, for more informative profiling results.
3982 * Default MI syntax changed to "mi2".
3984 The default MI (machine interface) syntax, enabled by the command line
3985 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3986 "mi1", can be enabled by specifying the option "-i=mi1".
3988 Support for the original "mi0" syntax (included in GDB 5.0) has been
3991 Fix for gdb/192: removed extraneous space when displaying frame level.
3992 Fix for gdb/672: update changelist is now output in mi list format.
3993 Fix for gdb/702: a -var-assign that updates the value now shows up
3994 in a subsequent -var-update.
3996 * New native configurations.
3998 FreeBSD/amd64 x86_64-*-freebsd*
4000 * Multi-arched targets.
4002 HP/PA HPUX11 hppa*-*-hpux*
4003 Renesas M32R/D w/simulator m32r-*-elf*
4005 * OBSOLETE configurations and files
4007 Configurations that have been declared obsolete in this release have
4008 been commented out. Unless there is activity to revive these
4009 configurations, the next release of GDB will have their sources
4010 permanently REMOVED.
4012 Z8000 simulator z8k-zilog-none or z8ksim
4013 Matsushita MN10200 w/simulator mn10200-*-*
4014 H8/500 simulator h8500-hitachi-hms or h8500hms
4015 HP/PA running BSD hppa*-*-bsd*
4016 HP/PA running OSF/1 hppa*-*-osf*
4017 HP/PA Pro target hppa*-*-pro*
4018 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4019 Sequent family i[3456]86-sequent-sysv4*
4020 i[3456]86-sequent-sysv*
4021 i[3456]86-sequent-bsd*
4022 Tsqware Sparclet sparclet-*-*
4023 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4025 * REMOVED configurations and files
4028 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4029 IBM AIX PS/2 i[3456]86-*-aix
4030 i386 running Mach 3.0 i[3456]86-*-mach3*
4031 i386 running Mach i[3456]86-*-mach*
4032 i386 running OSF/1 i[3456]86-*osf1mk*
4033 HP/Apollo 68k Family m68*-apollo*-sysv*,
4035 m68*-hp-bsd*, m68*-hp-hpux*
4036 Argonaut Risc Chip (ARC) arc-*-*
4037 Mitsubishi D30V d30v-*-*
4038 Fujitsu FR30 fr30-*-elf*
4039 OS/9000 i[34]86-*-os9k
4040 I960 with MON960 i960-*-coff
4042 * MIPS $fp behavior changed
4044 The convenience variable $fp, for the MIPS, now consistently returns
4045 the address of the current frame's base. Previously, depending on the
4046 context, $fp could refer to either $sp or the current frame's base
4047 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4048 The GNU Source-Level Debugger''.
4050 *** Changes in GDB 5.3:
4052 * GNU/Linux shared library multi-threaded performance improved.
4054 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4055 `/proc', in preference to `ptrace' for memory reads. This may result
4056 in an improvement in the start-up time of multi-threaded, shared
4057 library applications when run under GDB. One GDB user writes: ``loads
4058 shared libs like mad''.
4060 * ``gdbserver'' now supports multi-threaded applications on some targets
4062 Support for debugging multi-threaded applications which use
4063 the GNU/Linux LinuxThreads package has been added for
4064 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4065 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4067 * GDB now supports C/C++ preprocessor macros.
4069 GDB now expands preprocessor macro invocations in C/C++ expressions,
4070 and provides various commands for showing macro definitions and how
4073 The new command `macro expand EXPRESSION' expands any macro
4074 invocations in expression, and shows the result.
4076 The new command `show macro MACRO-NAME' shows the definition of the
4077 macro named MACRO-NAME, and where it was defined.
4079 Most compilers don't include information about macros in the debugging
4080 information by default. In GCC 3.1, for example, you need to compile
4081 your program with the options `-gdwarf-2 -g3'. If the macro
4082 information is present in the executable, GDB will read it.
4084 * Multi-arched targets.
4086 DEC Alpha (partial) alpha*-*-*
4087 DEC VAX (partial) vax-*-*
4089 National Semiconductor NS32000 (partial) ns32k-*-*
4090 Motorola 68000 (partial) m68k-*-*
4091 Motorola MCORE mcore-*-*
4095 Fujitsu FRV architecture added by Red Hat frv*-*-*
4098 * New native configurations
4100 Alpha NetBSD alpha*-*-netbsd*
4101 SH NetBSD sh*-*-netbsdelf*
4102 MIPS NetBSD mips*-*-netbsd*
4103 UltraSPARC NetBSD sparc64-*-netbsd*
4105 * OBSOLETE configurations and files
4107 Configurations that have been declared obsolete in this release have
4108 been commented out. Unless there is activity to revive these
4109 configurations, the next release of GDB will have their sources
4110 permanently REMOVED.
4112 Mitsubishi D30V d30v-*-*
4113 OS/9000 i[34]86-*-os9k
4114 IBM AIX PS/2 i[3456]86-*-aix
4115 Fujitsu FR30 fr30-*-elf*
4116 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4117 Argonaut Risc Chip (ARC) arc-*-*
4118 i386 running Mach 3.0 i[3456]86-*-mach3*
4119 i386 running Mach i[3456]86-*-mach*
4120 i386 running OSF/1 i[3456]86-*osf1mk*
4121 HP/Apollo 68k Family m68*-apollo*-sysv*,
4123 m68*-hp-bsd*, m68*-hp-hpux*
4124 I960 with MON960 i960-*-coff
4126 * OBSOLETE languages
4128 CHILL, a Pascal like language used by telecommunications companies.
4130 * REMOVED configurations and files
4132 AMD 29k family via UDI a29k-amd-udi, udi29k
4133 A29K VxWorks a29k-*-vxworks
4134 AMD 29000 embedded, using EBMON a29k-none-none
4135 AMD 29000 embedded with COFF a29k-none-coff
4136 AMD 29000 embedded with a.out a29k-none-aout
4138 testsuite/gdb.hp/gdb.threads-hp/ directory
4140 * New command "set max-user-call-depth <nnn>"
4142 This command allows the user to limit the call depth of user-defined
4143 commands. The default is 1024.
4145 * Changes in FreeBSD/i386 native debugging.
4147 Support for the "generate-core-file" has been added.
4149 * New commands "dump", "append", and "restore".
4151 These commands allow data to be copied from target memory
4152 to a bfd-format or binary file (dump and append), and back
4153 from a file into memory (restore).
4155 * Improved "next/step" support on multi-processor Alpha Tru64.
4157 The previous single-step mechanism could cause unpredictable problems,
4158 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4159 of a software single-step mechanism prevents this.
4161 *** Changes in GDB 5.2.1:
4169 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4170 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4171 Fix, by Joel Brobecker imported from mainline.
4173 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4174 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4175 Fix, by Fred Fish, imported from mainline.
4177 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4178 Surprisingly enough, it works now.
4179 By Michal Ludvig, imported from mainline.
4181 i386 hardware watchpoint support:
4182 avoid misses on second run for some targets.
4183 By Pierre Muller, imported from mainline.
4185 *** Changes in GDB 5.2:
4187 * New command "set trust-readonly-sections on[off]".
4189 This command is a hint that tells gdb that read-only sections
4190 really are read-only (ie. that their contents will not change).
4191 In this mode, gdb will go to the object file rather than the
4192 target to read memory from read-only sections (such as ".text").
4193 This can be a significant performance improvement on some
4194 (notably embedded) targets.
4196 * New command "generate-core-file" (or "gcore").
4198 This new gdb command allows the user to drop a core file of the child
4199 process state at any time. So far it's been implemented only for
4200 GNU/Linux and Solaris, but should be relatively easily ported to other
4201 hosts. Argument is core file name (defaults to core.<pid>).
4203 * New command line option
4205 GDB now accepts --pid or -p followed by a process id.
4207 * Change in command line behavior -- corefiles vs. process ids.
4209 There is a subtle behavior in the way in which GDB handles
4210 command line arguments. The first non-flag argument is always
4211 a program to debug, but the second non-flag argument may either
4212 be a corefile or a process id. Previously, GDB would attempt to
4213 open the second argument as a corefile, and if that failed, would
4214 issue a superfluous error message and then attempt to attach it as
4215 a process. Now, if the second argument begins with a non-digit,
4216 it will be treated as a corefile. If it begins with a digit,
4217 GDB will attempt to attach it as a process, and if no such process
4218 is found, will then attempt to open it as a corefile.
4220 * Changes in ARM configurations.
4222 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4223 configuration is fully multi-arch.
4225 * New native configurations
4227 ARM NetBSD arm*-*-netbsd*
4228 x86 OpenBSD i[3456]86-*-openbsd*
4229 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4230 Sparc64 running FreeBSD sparc64-*-freebsd*
4234 Sanyo XStormy16 xstormy16-elf
4236 * OBSOLETE configurations and files
4238 Configurations that have been declared obsolete in this release have
4239 been commented out. Unless there is activity to revive these
4240 configurations, the next release of GDB will have their sources
4241 permanently REMOVED.
4243 AMD 29k family via UDI a29k-amd-udi, udi29k
4244 A29K VxWorks a29k-*-vxworks
4245 AMD 29000 embedded, using EBMON a29k-none-none
4246 AMD 29000 embedded with COFF a29k-none-coff
4247 AMD 29000 embedded with a.out a29k-none-aout
4249 testsuite/gdb.hp/gdb.threads-hp/ directory
4251 * REMOVED configurations and files
4253 TI TMS320C80 tic80-*-*
4255 PowerPC Solaris powerpcle-*-solaris*
4256 PowerPC Windows NT powerpcle-*-cygwin32
4257 PowerPC Netware powerpc-*-netware*
4258 Harris/CXUX m88k m88*-harris-cxux*
4259 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4260 ns32k-utek-sysv* ns32k-utek-*
4261 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4262 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4263 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4264 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4265 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4267 * Changes to command line processing
4269 The new `--args' feature can be used to specify command-line arguments
4270 for the inferior from gdb's command line.
4272 * Changes to key bindings
4274 There is a new `operate-and-get-next' function bound to `C-o'.
4276 *** Changes in GDB 5.1.1
4278 Fix compile problem on DJGPP.
4280 Fix a problem with floating-point registers on the i386 being
4283 Fix to stop GDB crashing on .debug_str debug info.
4285 Numerous documentation fixes.
4287 Numerous testsuite fixes.
4289 *** Changes in GDB 5.1:
4291 * New native configurations
4293 Alpha FreeBSD alpha*-*-freebsd*
4294 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4295 MIPS GNU/Linux mips*-*-linux*
4296 MIPS SGI Irix 6.x mips*-sgi-irix6*
4297 ia64 AIX ia64-*-aix*
4298 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4302 Motorola 68HC11 and 68HC12 m68hc11-elf
4304 UltraSparc running GNU/Linux sparc64-*-linux*
4306 * OBSOLETE configurations and files
4308 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4309 Harris/CXUX m88k m88*-harris-cxux*
4310 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4311 ns32k-utek-sysv* ns32k-utek-*
4312 TI TMS320C80 tic80-*-*
4314 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4315 PowerPC Solaris powerpcle-*-solaris*
4316 PowerPC Windows NT powerpcle-*-cygwin32
4317 PowerPC Netware powerpc-*-netware*
4318 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4319 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4320 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4321 Apple Macintosh (MPW) host N/A
4323 stuff.c (Program to stuff files into a specially prepared space in kdb)
4324 kdb-start.c (Main loop for the standalone kernel debugger)
4326 Configurations that have been declared obsolete in this release have
4327 been commented out. Unless there is activity to revive these
4328 configurations, the next release of GDB will have their sources
4329 permanently REMOVED.
4331 * REMOVED configurations and files
4333 Altos 3068 m68*-altos-*
4334 Convex c1-*-*, c2-*-*
4336 ARM RISCix arm-*-* (as host)
4340 * GDB has been converted to ISO C.
4342 GDB's source code has been converted to ISO C. In particular, the
4343 sources are fully protoized, and rely on standard headers being
4348 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4350 * The MI enabled by default.
4352 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4353 revised and enabled by default. Packages which use GDB as a debugging
4354 engine behind a UI or another front end are encouraged to switch to
4355 using the GDB/MI interface, instead of the old annotations interface
4356 which is now deprecated.
4358 * Support for debugging Pascal programs.
4360 GDB now includes support for debugging Pascal programs. The following
4361 main features are supported:
4363 - Pascal-specific data types such as sets;
4365 - automatic recognition of Pascal sources based on file-name
4368 - Pascal-style display of data types, variables, and functions;
4370 - a Pascal expression parser.
4372 However, some important features are not yet supported.
4374 - Pascal string operations are not supported at all;
4376 - there are some problems with boolean types;
4378 - Pascal type hexadecimal constants are not supported
4379 because they conflict with the internal variables format;
4381 - support for Pascal objects and classes is not full yet;
4383 - unlike Pascal, GDB is case-sensitive for symbol names.
4385 * Changes in completion.
4387 Commands such as `shell', `run' and `set args', which pass arguments
4388 to inferior programs, now complete on file names, similar to what
4389 users expect at the shell prompt.
4391 Commands which accept locations, such as `disassemble', `print',
4392 `breakpoint', `until', etc. now complete on filenames as well as
4393 program symbols. Thus, if you type "break foob TAB", and the source
4394 files linked into the programs include `foobar.c', that file name will
4395 be one of the candidates for completion. However, file names are not
4396 considered for completion after you typed a colon that delimits a file
4397 name from a name of a function in that file, as in "break foo.c:bar".
4399 `set demangle-style' completes on available demangling styles.
4401 * New platform-independent commands:
4403 It is now possible to define a post-hook for a command as well as a
4404 hook that runs before the command. For more details, see the
4405 documentation of `hookpost' in the GDB manual.
4407 * Changes in GNU/Linux native debugging.
4409 Support for debugging multi-threaded programs has been completely
4410 revised for all platforms except m68k and sparc. You can now debug as
4411 many threads as your system allows you to have.
4413 Attach/detach is supported for multi-threaded programs.
4415 Support for SSE registers was added for x86. This doesn't work for
4416 multi-threaded programs though.
4418 * Changes in MIPS configurations.
4420 Multi-arch support is enabled for all MIPS configurations.
4422 GDB can now be built as native debugger on SGI Irix 6.x systems for
4423 debugging n32 executables. (Debugging 64-bit executables is not yet
4426 * Unified support for hardware watchpoints in all x86 configurations.
4428 Most (if not all) native x86 configurations support hardware-assisted
4429 breakpoints and watchpoints in a unified manner. This support
4430 implements debug register sharing between watchpoints, which allows to
4431 put a virtually infinite number of watchpoints on the same address,
4432 and also supports watching regions up to 16 bytes with several debug
4435 The new maintenance command `maintenance show-debug-regs' toggles
4436 debugging print-outs in functions that insert, remove, and test
4437 watchpoints and hardware breakpoints.
4439 * Changes in the DJGPP native configuration.
4441 New command ``info dos sysinfo'' displays assorted information about
4442 the CPU, OS, memory, and DPMI server.
4444 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4445 display information about segment descriptors stored in GDT, LDT, and
4448 New commands ``info dos pde'' and ``info dos pte'' display entries
4449 from Page Directory and Page Tables (for now works with CWSDPMI only).
4450 New command ``info dos address-pte'' displays the Page Table entry for
4451 a given linear address.
4453 GDB can now pass command lines longer than 126 characters to the
4454 program being debugged (requires an update to the libdbg.a library
4455 which is part of the DJGPP development kit).
4457 DWARF2 debug info is now supported.
4459 It is now possible to `step' and `next' through calls to `longjmp'.
4461 * Changes in documentation.
4463 All GDB documentation was converted to GFDL, the GNU Free
4464 Documentation License.
4466 Tracepoints-related commands are now fully documented in the GDB
4469 TUI, the Text-mode User Interface, is now documented in the manual.
4471 Tracepoints-related commands are now fully documented in the GDB
4474 The "GDB Internals" manual now has an index. It also includes
4475 documentation of `ui_out' functions, GDB coding standards, x86
4476 hardware watchpoints, and memory region attributes.
4478 * GDB's version number moved to ``version.in''
4480 The Makefile variable VERSION has been replaced by the file
4481 ``version.in''. People creating GDB distributions should update the
4482 contents of this file.
4486 GUD support is now a standard part of the EMACS distribution.
4488 *** Changes in GDB 5.0:
4490 * Improved support for debugging FP programs on x86 targets
4492 Unified and much-improved support for debugging floating-point
4493 programs on all x86 targets. In particular, ``info float'' now
4494 displays the FP registers in the same format on all x86 targets, with
4495 greater level of detail.
4497 * Improvements and bugfixes in hardware-assisted watchpoints
4499 It is now possible to watch array elements, struct members, and
4500 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4501 on x86 targets no longer erroneously trigger when the address is
4504 * Improvements in the native DJGPP version of GDB
4506 The distribution now includes all the scripts and auxiliary files
4507 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4508 machines ``out of the box''.
4510 The DJGPP version can now debug programs that use signals. It is
4511 possible to catch signals that happened in the debuggee, deliver
4512 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4513 would kill the program being debugged.) Programs that hook hardware
4514 interrupts (keyboard, timer, etc.) can also be debugged.
4516 It is now possible to debug DJGPP programs that redirect their
4517 standard handles or switch them to raw (as opposed to cooked) mode, or
4518 even close them. The command ``run < foo > bar'' works as expected,
4519 and ``info terminal'' reports useful information about the debuggee's
4520 terminal, including raw/cooked mode, redirection, etc.
4522 The DJGPP version now uses termios functions for console I/O, which
4523 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4526 DOS-style file names with drive letters are now fully supported by
4529 It is now possible to debug DJGPP programs that switch their working
4530 directory. It is also possible to rerun the debuggee any number of
4531 times without restarting GDB; thus, you can use the same setup,
4532 breakpoints, etc. for many debugging sessions.
4534 * New native configurations
4536 ARM GNU/Linux arm*-*-linux*
4537 PowerPC GNU/Linux powerpc-*-linux*
4541 Motorola MCore mcore-*-*
4542 x86 VxWorks i[3456]86-*-vxworks*
4543 PowerPC VxWorks powerpc-*-vxworks*
4544 TI TMS320C80 tic80-*-*
4546 * OBSOLETE configurations
4548 Altos 3068 m68*-altos-*
4549 Convex c1-*-*, c2-*-*
4551 ARM RISCix arm-*-* (as host)
4554 Configurations that have been declared obsolete will be commented out,
4555 but the code will be left in place. If there is no activity to revive
4556 these configurations before the next release of GDB, the sources will
4557 be permanently REMOVED.
4559 * Gould support removed
4561 Support for the Gould PowerNode and NP1 has been removed.
4563 * New features for SVR4
4565 On SVR4 native platforms (such as Solaris), if you attach to a process
4566 without first loading a symbol file, GDB will now attempt to locate and
4567 load symbols from the running process's executable file.
4569 * Many C++ enhancements
4571 C++ support has been greatly improved. Overload resolution now works properly
4572 in almost all cases. RTTI support is on the way.
4574 * Remote targets can connect to a sub-program
4576 A popen(3) style serial-device has been added. This device starts a
4577 sub-process (such as a stand-alone simulator) and then communicates
4578 with that. The sub-program to run is specified using the syntax
4579 ``|<program> <args>'' vis:
4581 (gdb) set remotedebug 1
4582 (gdb) target extended-remote |mn10300-elf-sim program-args
4584 * MIPS 64 remote protocol
4586 A long standing bug in the mips64 remote protocol where by GDB
4587 expected certain 32 bit registers (ex SR) to be transfered as 32
4588 instead of 64 bits has been fixed.
4590 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4591 added to provide backward compatibility with older versions of GDB.
4593 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4595 The command ``set remotebinarydownload'' command has been replaced by
4596 ``set remote X-packet''. Other commands in ``set remote'' family
4597 include ``set remote P-packet''.
4599 * Breakpoint commands accept ranges.
4601 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4602 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4603 ``tracepoint passcount'' also accepts a range of tracepoints.
4605 * ``apropos'' command added.
4607 The ``apropos'' command searches through command names and
4608 documentation strings, printing out matches, making it much easier to
4609 try to find a command that does what you are looking for.
4613 A new machine oriented interface (MI) has been added to GDB. This
4614 interface is designed for debug environments running GDB as a separate
4615 process. This is part of the long term libGDB project. See the
4616 "GDB/MI" chapter of the GDB manual for further information. It can be
4617 enabled by configuring with:
4619 .../configure --enable-gdbmi
4621 *** Changes in GDB-4.18:
4623 * New native configurations
4625 HP-UX 10.20 hppa*-*-hpux10.20
4626 HP-UX 11.x hppa*-*-hpux11.0*
4627 M68K GNU/Linux m68*-*-linux*
4631 Fujitsu FR30 fr30-*-elf*
4632 Intel StrongARM strongarm-*-*
4633 Mitsubishi D30V d30v-*-*
4635 * OBSOLETE configurations
4637 Gould PowerNode, NP1 np1-*-*, pn-*-*
4639 Configurations that have been declared obsolete will be commented out,
4640 but the code will be left in place. If there is no activity to revive
4641 these configurations before the next release of GDB, the sources will
4642 be permanently REMOVED.
4646 As a compatibility experiment, GDB's source files buildsym.h and
4647 buildsym.c have been converted to pure standard C, no longer
4648 containing any K&R compatibility code. We believe that all systems in
4649 use today either come with a standard C compiler, or have a GCC port
4650 available. If this is not true, please report the affected
4651 configuration to bug-gdb@gnu.org immediately. See the README file for
4652 information about getting a standard C compiler if you don't have one
4657 GDB now uses readline 2.2.
4659 * set extension-language
4661 You can now control the mapping between filename extensions and source
4662 languages by using the `set extension-language' command. For instance,
4663 you can ask GDB to treat .c files as C++ by saying
4664 set extension-language .c c++
4665 The command `info extensions' lists all of the recognized extensions
4666 and their associated languages.
4668 * Setting processor type for PowerPC and RS/6000
4670 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4671 you can use the `set processor' command to specify what variant of the
4672 PowerPC family you are debugging. The command
4676 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4677 following PowerPC and RS6000 variants:
4679 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4680 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4682 403GC IBM PowerPC 403GC
4683 505 Motorola PowerPC 505
4684 860 Motorola PowerPC 860 or 850
4685 601 Motorola PowerPC 601
4686 602 Motorola PowerPC 602
4687 603 Motorola/IBM PowerPC 603 or 603e
4688 604 Motorola PowerPC 604 or 604e
4689 750 Motorola/IBM PowerPC 750 or 750
4691 At the moment, this command just tells GDB what to name the
4692 special-purpose processor registers. Since almost all the affected
4693 registers are inaccessible to user-level programs, this command is
4694 only useful for remote debugging in its present form.
4698 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4699 more extensive support for HP-UX. Added features include shared
4700 library support, kernel threads and hardware watchpoints for 11.00,
4701 support for HP's ANSI C and C++ compilers, and a compatibility mode
4702 for xdb and dbx commands.
4706 HP's donation includes the new concept of catchpoints, which is a
4707 generalization of the old catch command. On HP-UX, it is now possible
4708 to catch exec, fork, and vfork, as well as library loading.
4710 This means that the existing catch command has changed; its first
4711 argument now specifies the type of catch to be set up. See the
4712 output of "help catch" for a list of catchpoint types.
4714 * Debugging across forks
4716 On HP-UX, you can choose which process to debug when a fork() happens
4721 HP has donated a curses-based terminal user interface (TUI). To get
4722 it, build with --enable-tui. Although this can be enabled for any
4723 configuration, at present it only works for native HP debugging.
4725 * GDB remote protocol additions
4727 A new protocol packet 'X' that writes binary data is now available.
4728 Default behavior is to try 'X', then drop back to 'M' if the stub
4729 fails to respond. The settable variable `remotebinarydownload'
4730 allows explicit control over the use of 'X'.
4732 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4733 full 64-bit address. The command
4735 set remoteaddresssize 32
4737 can be used to revert to the old behaviour. For existing remote stubs
4738 the change should not be noticed, as the additional address information
4741 In order to assist in debugging stubs, you may use the maintenance
4742 command `packet' to send any text string to the stub. For instance,
4744 maint packet heythere
4746 sends the packet "$heythere#<checksum>". Note that it is very easy to
4747 disrupt a debugging session by sending the wrong packet at the wrong
4750 The compare-sections command allows you to compare section data on the
4751 target to what is in the executable file without uploading or
4752 downloading, by comparing CRC checksums.
4754 * Tracing can collect general expressions
4756 You may now collect general expressions at tracepoints. This requires
4757 further additions to the target-side stub; see tracepoint.c and
4758 doc/agentexpr.texi for further details.
4760 * mask-address variable for Mips
4762 For Mips targets, you may control the zeroing of the upper 32 bits of
4763 a 64-bit address by entering `set mask-address on'. This is mainly
4764 of interest to users of embedded R4xxx and R5xxx processors.
4766 * Higher serial baud rates
4768 GDB's serial code now allows you to specify baud rates 57600, 115200,
4769 230400, and 460800 baud. (Note that your host system may not be able
4770 to achieve all of these rates.)
4774 The i960 configuration now includes an initial implementation of a
4775 builtin simulator, contributed by Jim Wilson.
4778 *** Changes in GDB-4.17:
4780 * New native configurations
4782 Alpha GNU/Linux alpha*-*-linux*
4783 Unixware 2.x i[3456]86-unixware2*
4784 Irix 6.x mips*-sgi-irix6*
4785 PowerPC GNU/Linux powerpc-*-linux*
4786 PowerPC Solaris powerpcle-*-solaris*
4787 Sparc GNU/Linux sparc-*-linux*
4788 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4792 Argonaut Risc Chip (ARC) arc-*-*
4793 Hitachi H8/300S h8300*-*-*
4794 Matsushita MN10200 w/simulator mn10200-*-*
4795 Matsushita MN10300 w/simulator mn10300-*-*
4796 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4797 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4798 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4799 Mitsubishi D10V w/simulator d10v-*-*
4800 Mitsubishi M32R/D w/simulator m32r-*-elf*
4801 Tsqware Sparclet sparclet-*-*
4802 NEC V850 w/simulator v850-*-*
4804 * New debugging protocols
4806 ARM with RDI protocol arm*-*-*
4807 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4808 DDB and LSI variants of PMON protocol mips*-*-*
4809 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4810 PowerPC with SDS protocol powerpc{,le}-*-eabi
4811 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4815 All configurations can now understand and use the DWARF 2 debugging
4816 format. The choice is automatic, if the symbol file contains DWARF 2
4821 GDB now includes basic Java language support. This support is
4822 only useful with Java compilers that produce native machine code.
4824 * solib-absolute-prefix and solib-search-path
4826 For SunOS and SVR4 shared libraries, you may now set the prefix for
4827 loading absolute shared library symbol files, and the search path for
4828 locating non-absolute shared library symbol files.
4830 * Live range splitting
4832 GDB can now effectively debug code for which GCC has performed live
4833 range splitting as part of its optimization. See gdb/doc/LRS for
4834 more details on the expected format of the stabs information.
4838 GDB's support for the GNU Hurd, including thread debugging, has been
4839 updated to work with current versions of the Hurd.
4843 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4844 instruction set. ARM GDB automatically detects when Thumb
4845 instructions are in use, and adjusts disassembly and backtracing
4850 GDB's MIPS target configurations now handle the MIP16 16-bit
4855 GDB now includes support for overlays; if an executable has been
4856 linked such that multiple sections are based at the same address, GDB
4857 will decide which section to use for symbolic info. You can choose to
4858 control the decision manually, using overlay commands, or implement
4859 additional target-side support and use "overlay load-target" to bring
4860 in the overlay mapping. Do "help overlay" for more detail.
4864 The command "info symbol <address>" displays information about
4865 the symbol at the specified address.
4869 The standard remote protocol now includes an extension that allows
4870 asynchronous collection and display of trace data. This requires
4871 extensive support in the target-side debugging stub. Tracing mode
4872 includes a new interaction mode in GDB and new commands: see the
4873 file tracepoint.c for more details.
4877 Configurations for embedded MIPS now include a simulator contributed
4878 by Cygnus Solutions. The simulator supports the instruction sets
4879 of most MIPS variants.
4883 Sparc configurations may now include the ERC32 simulator contributed
4884 by the European Space Agency. The simulator is not built into
4885 Sparc targets by default; configure with --enable-sim to include it.
4889 For target configurations that may include multiple variants of a
4890 basic architecture (such as MIPS and SH), you may now set the
4891 architecture explicitly. "set arch" sets, "info arch" lists
4892 the possible architectures.
4894 *** Changes in GDB-4.16:
4896 * New native configurations
4898 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4899 M68K NetBSD m68k-*-netbsd*
4900 PowerPC AIX 4.x powerpc-*-aix*
4901 PowerPC MacOS powerpc-*-macos*
4902 PowerPC Windows NT powerpcle-*-cygwin32
4903 RS/6000 AIX 4.x rs6000-*-aix4*
4907 ARM with RDP protocol arm-*-*
4908 I960 with MON960 i960-*-coff
4909 MIPS VxWorks mips*-*-vxworks*
4910 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4911 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4913 Matra Sparclet sparclet-*-*
4917 The powerpc-eabi configuration now includes the PSIM simulator,
4918 contributed by Andrew Cagney, with assistance from Mike Meissner.
4919 PSIM is a very elaborate model of the PowerPC, including not only
4920 basic instruction set execution, but also details of execution unit
4921 performance and I/O hardware. See sim/ppc/README for more details.
4925 GDB now works with Solaris 2.5.
4927 * Windows 95/NT native
4929 GDB will now work as a native debugger on Windows 95 and Windows NT.
4930 To build it from source, you must use the "gnu-win32" environment,
4931 which uses a DLL to emulate enough of Unix to run the GNU tools.
4932 Further information, binaries, and sources are available at
4933 ftp.cygnus.com, under pub/gnu-win32.
4935 * dont-repeat command
4937 If a user-defined command includes the command `dont-repeat', then the
4938 command will not be repeated if the user just types return. This is
4939 useful if the command is time-consuming to run, so that accidental
4940 extra keystrokes don't run the same command many times.
4942 * Send break instead of ^C
4944 The standard remote protocol now includes an option to send a break
4945 rather than a ^C to the target in order to interrupt it. By default,
4946 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4948 * Remote protocol timeout
4950 The standard remote protocol includes a new variable `remotetimeout'
4951 that allows you to set the number of seconds before GDB gives up trying
4952 to read from the target. The default value is 2.
4954 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4956 By default GDB will automatically keep track of objects as they are
4957 loaded and unloaded by the dynamic linker. By using the command `set
4958 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4959 when shared library events occur, thus allowing you to set breakpoints
4960 in shared libraries which are explicitly loaded by the inferior.
4962 Note this feature does not work on hpux8. On hpux9 you must link
4963 /usr/lib/end.o into your program. This feature should work
4964 automatically on hpux10.
4966 * Irix 5.x hardware watchpoint support
4968 Irix 5 configurations now support the use of hardware watchpoints.
4970 * Mips protocol "SYN garbage limit"
4972 When debugging a Mips target using the `target mips' protocol, you
4973 may set the number of characters that GDB will ignore by setting
4974 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4975 every character. The default value is 1050.
4977 * Recording and replaying remote debug sessions
4979 If you set `remotelogfile' to the name of a file, gdb will write to it
4980 a recording of a remote debug session. This recording may then be
4981 replayed back to gdb using "gdbreplay". See gdbserver/README for
4982 details. This is useful when you have a problem with GDB while doing
4983 remote debugging; you can make a recording of the session and send it
4984 to someone else, who can then recreate the problem.
4986 * Speedups for remote debugging
4988 GDB includes speedups for downloading and stepping MIPS systems using
4989 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4990 and more efficient S-record downloading.
4992 * Memory use reductions and statistics collection
4994 GDB now uses less memory and reports statistics about memory usage.
4995 Try the `maint print statistics' command, for example.
4997 *** Changes in GDB-4.15:
4999 * Psymtabs for XCOFF
5001 The symbol reader for AIX GDB now uses partial symbol tables. This
5002 can greatly improve startup time, especially for large executables.
5004 * Remote targets use caching
5006 Remote targets now use a data cache to speed up communication with the
5007 remote side. The data cache could lead to incorrect results because
5008 it doesn't know about volatile variables, thus making it impossible to
5009 debug targets which use memory mapped I/O devices. `set remotecache
5010 off' turns the the data cache off.
5012 * Remote targets may have threads
5014 The standard remote protocol now includes support for multiple threads
5015 in the target system, using new protocol commands 'H' and 'T'. See
5016 gdb/remote.c for details.
5020 If GDB is configured with `--enable-netrom', then it will include
5021 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5022 acts as though it is a bank of ROM on the target board, but you can
5023 write into it over the network. GDB's support consists only of
5024 support for fast loading into the emulated ROM; to debug, you must use
5025 another protocol, such as standard remote protocol. The usual
5026 sequence is something like
5028 target nrom <netrom-hostname>
5030 target remote <netrom-hostname>:1235
5034 GDB now includes support for the Apple Macintosh, as a host only. It
5035 may be run as either an MPW tool or as a standalone application, and
5036 it can debug through the serial port. All the usual GDB commands are
5037 available, but to the target command, you must supply "serial" as the
5038 device type instead of "/dev/ttyXX". See mpw-README in the main
5039 directory for more information on how to build. The MPW configuration
5040 scripts */mpw-config.in support only a few targets, and only the
5041 mips-idt-ecoff target has been tested.
5045 GDB configuration now uses autoconf. This is not user-visible,
5046 but does simplify configuration and building.
5050 GDB now supports hpux10.
5052 *** Changes in GDB-4.14:
5054 * New native configurations
5056 x86 FreeBSD i[345]86-*-freebsd
5057 x86 NetBSD i[345]86-*-netbsd
5058 NS32k NetBSD ns32k-*-netbsd
5059 Sparc NetBSD sparc-*-netbsd
5063 A29K VxWorks a29k-*-vxworks
5064 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5065 CPU32 EST-300 emulator m68*-*-est*
5066 PowerPC ELF powerpc-*-elf
5069 * Alpha OSF/1 support for procfs
5071 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5072 possible to attach to running processes. As the mounting of the /proc
5073 filesystem is optional on the Alpha, GDB automatically determines
5074 the availability of /proc during startup. This can lead to problems
5075 if /proc is unmounted after GDB has been started.
5077 * Arguments to user-defined commands
5079 User commands may accept up to 10 arguments separated by whitespace.
5080 Arguments are accessed within the user command via $arg0..$arg9. A
5083 print $arg0 + $arg1 + $arg2
5085 To execute the command use:
5088 Defines the command "adder" which prints the sum of its three arguments.
5089 Note the arguments are text substitutions, so they may reference variables,
5090 use complex expressions, or even perform inferior function calls.
5092 * New `if' and `while' commands
5094 This makes it possible to write more sophisticated user-defined
5095 commands. Both commands take a single argument, which is the
5096 expression to evaluate, and must be followed by the commands to
5097 execute, one per line, if the expression is nonzero, the list being
5098 terminated by the word `end'. The `if' command list may include an
5099 `else' word, which causes the following commands to be executed only
5100 if the expression is zero.
5102 * Fortran source language mode
5104 GDB now includes partial support for Fortran 77. It will recognize
5105 Fortran programs and can evaluate a subset of Fortran expressions, but
5106 variables and functions may not be handled correctly. GDB will work
5107 with G77, but does not yet know much about symbols emitted by other
5110 * Better HPUX support
5112 Most debugging facilities now work on dynamic executables for HPPAs
5113 running hpux9 or later. You can attach to running dynamically linked
5114 processes, but by default the dynamic libraries will be read-only, so
5115 for instance you won't be able to put breakpoints in them. To change
5116 that behavior do the following before running the program:
5122 This will cause the libraries to be mapped private and read-write.
5123 To revert to the normal behavior, do this:
5129 You cannot set breakpoints or examine data in the library until after
5130 the library is loaded if the function/data symbols do not have
5133 GDB can now also read debug symbols produced by the HP C compiler on
5134 HPPAs (sorry, no C++, Fortran or 68k support).
5136 * Target byte order now dynamically selectable
5138 You can choose which byte order to use with a target system, via the
5139 commands "set endian big" and "set endian little", and you can see the
5140 current setting by using "show endian". You can also give the command
5141 "set endian auto", in which case GDB will use the byte order
5142 associated with the executable. Currently, only embedded MIPS
5143 configurations support dynamic selection of target byte order.
5145 * New DOS host serial code
5147 This version uses DPMI interrupts to handle buffered I/O, so you
5148 no longer need to run asynctsr when debugging boards connected to
5151 *** Changes in GDB-4.13:
5153 * New "complete" command
5155 This lists all the possible completions for the rest of the line, if it
5156 were to be given as a command itself. This is intended for use by emacs.
5158 * Trailing space optional in prompt
5160 "set prompt" no longer adds a space for you after the prompt you set. This
5161 allows you to set a prompt which ends in a space or one that does not.
5163 * Breakpoint hit counts
5165 "info break" now displays a count of the number of times the breakpoint
5166 has been hit. This is especially useful in conjunction with "ignore"; you
5167 can ignore a large number of breakpoint hits, look at the breakpoint info
5168 to see how many times the breakpoint was hit, then run again, ignoring one
5169 less than that number, and this will get you quickly to the last hit of
5172 * Ability to stop printing at NULL character
5174 "set print null-stop" will cause GDB to stop printing the characters of
5175 an array when the first NULL is encountered. This is useful when large
5176 arrays actually contain only short strings.
5178 * Shared library breakpoints
5180 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5181 breakpoints in shared libraries before the executable is run.
5183 * Hardware watchpoints
5185 There is a new hardware breakpoint for the watch command for sparclite
5186 targets. See gdb/sparclite/hw_breakpoint.note.
5188 Hardware watchpoints are also now supported under GNU/Linux.
5192 Annotations have been added. These are for use with graphical interfaces,
5193 and are still experimental. Currently only gdba.el uses these.
5195 * Improved Irix 5 support
5197 GDB now works properly with Irix 5.2.
5199 * Improved HPPA support
5201 GDB now works properly with the latest GCC and GAS.
5203 * New native configurations
5205 Sequent PTX4 i[34]86-sequent-ptx4
5206 HPPA running OSF/1 hppa*-*-osf*
5207 Atari TT running SVR4 m68*-*-sysv4*
5208 RS/6000 LynxOS rs6000-*-lynxos*
5212 OS/9000 i[34]86-*-os9k
5213 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5216 * Hitachi SH7000 and E7000-PC ICE support
5218 There is now support for communicating with the Hitachi E7000-PC ICE.
5219 This is available automatically when GDB is configured for the SH.
5223 As usual, a variety of small fixes and improvements, both generic
5224 and configuration-specific. See the ChangeLog for more detail.
5226 *** Changes in GDB-4.12:
5228 * Irix 5 is now supported
5232 GDB-4.12 on the HPPA has a number of changes which make it unable
5233 to debug the output from the currently released versions of GCC and
5234 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5235 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5236 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5239 *** Changes in GDB-4.11:
5241 * User visible changes:
5245 The "set remotedebug" option is now consistent between the mips remote
5246 target, remote targets using the gdb-specific protocol, UDI (AMD's
5247 debug protocol for the 29k) and the 88k bug monitor. It is now an
5248 integer specifying a debug level (normally 0 or 1, but 2 means more
5249 debugging info for the mips target).
5251 * DEC Alpha native support
5253 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5254 debug info, but GDB works fairly well with the DEC compiler and should
5255 work with a future GCC release. See the README file for a few
5256 Alpha-specific notes.
5258 * Preliminary thread implementation
5260 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5262 * LynxOS native and target support for 386
5264 This release has been hosted on LynxOS 2.2, and also can be configured
5265 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5268 * Improvements in C++ mangling/demangling.
5270 This release has much better g++ debugging, specifically in name
5271 mangling/demangling, virtual function calls, print virtual table,
5272 call methods, ...etc.
5274 *** Changes in GDB-4.10:
5276 * User visible changes:
5278 Remote debugging using the GDB-specific (`target remote') protocol now
5279 supports the `load' command. This is only useful if you have some
5280 other way of getting the stub to the target system, and you can put it
5281 somewhere in memory where it won't get clobbered by the download.
5283 Filename completion now works.
5285 When run under emacs mode, the "info line" command now causes the
5286 arrow to point to the line specified. Also, "info line" prints
5287 addresses in symbolic form (as well as hex).
5289 All vxworks based targets now support a user settable option, called
5290 vxworks-timeout. This option represents the number of seconds gdb
5291 should wait for responses to rpc's. You might want to use this if
5292 your vxworks target is, perhaps, a slow software simulator or happens
5293 to be on the far side of a thin network line.
5297 This release contains support for using a DEC alpha as a GDB host for
5298 cross debugging. Native alpha debugging is not supported yet.
5301 *** Changes in GDB-4.9:
5305 This is the first GDB release which is accompanied by a matching testsuite.
5306 The testsuite requires installation of dejagnu, which should be available
5307 via ftp from most sites that carry GNU software.
5311 'Cfront' style demangling has had its name changed to 'ARM' style, to
5312 emphasize that it was written from the specifications in the C++ Annotated
5313 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5314 disclaimers, it still generated too much confusion with users attempting to
5315 use gdb with AT&T cfront.
5319 GDB now uses a standard remote interface to a simulator library.
5320 So far, the library contains simulators for the Zilog Z8001/2, the
5321 Hitachi H8/300, H8/500 and Super-H.
5323 * New targets supported
5325 H8/300 simulator h8300-hitachi-hms or h8300hms
5326 H8/500 simulator h8500-hitachi-hms or h8500hms
5327 SH simulator sh-hitachi-hms or sh
5328 Z8000 simulator z8k-zilog-none or z8ksim
5329 IDT MIPS board over serial line mips-idt-ecoff
5331 Cross-debugging to GO32 targets is supported. It requires a custom
5332 version of the i386-stub.c module which is integrated with the
5333 GO32 memory extender.
5335 * New remote protocols
5337 MIPS remote debugging protocol.
5339 * New source languages supported
5341 This version includes preliminary support for Chill, a Pascal like language
5342 used by telecommunications companies. Chill support is also being integrated
5343 into the GNU compiler, but we don't know when it will be publically available.
5346 *** Changes in GDB-4.8:
5348 * HP Precision Architecture supported
5350 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5351 version of this support was available as a set of patches from the
5352 University of Utah. GDB does not support debugging of programs
5353 compiled with the HP compiler, because HP will not document their file
5354 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5355 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5357 Many problems in the preliminary version have been fixed.
5359 * Faster and better demangling
5361 We have improved template demangling and fixed numerous bugs in the GNU style
5362 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5363 character types (wchar_t) are now supported. Demangling of each symbol is now
5364 only done once, and is cached when the symbol table for a file is read in.
5365 This results in a small increase in memory usage for C programs, a moderate
5366 increase in memory usage for C++ programs, and a fantastic speedup in
5369 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5370 from the specifications in the Annotated Reference Manual, which AT&T's
5371 compiler does not actually implement.
5373 * G++ multiple inheritance compiler problem
5375 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5376 inheritance lattices was reworked to properly discover ambiguities. We
5377 recently found an example which causes this new algorithm to fail in a
5378 very subtle way, producing bad debug information for those classes.
5379 The file 'gcc.patch' (in this directory) can be applied to gcc to
5380 circumvent the problem. A future GCC release will contain a complete
5383 The previous G++ debug info problem (mentioned below for the gdb-4.7
5384 release) is fixed in gcc version 2.3.2.
5386 * Improved configure script
5388 The `configure' script will now attempt to guess your system type if
5389 you don't supply a host system type. The old scheme of supplying a
5390 host system triplet is preferable over using this. All the magic is
5391 done in the new `config.guess' script. Examine it for details.
5393 We have also brought our configure script much more in line with the FSF's
5394 version. It now supports the --with-xxx options. In particular,
5395 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5396 The resulting GDB will not be able to read arbitrary object file formats --
5397 only the format ``expected'' to be used on the configured target system.
5398 We hope to make this the default in a future release.
5400 * Documentation improvements
5402 There's new internal documentation on how to modify GDB, and how to
5403 produce clean changes to the code. We implore people to read it
5404 before submitting changes.
5406 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5407 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5408 `info' files are also provided. To build `info' files from scratch,
5409 you will need the latest `makeinfo' release, which will be available in
5410 a future texinfo-X.Y release.
5412 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5413 We're not sure exactly which versions have this problem, but it has
5414 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5415 or better. If that isn't possible, there is a patch in
5416 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5417 around this problem.
5421 GDB now supports array constants that can be used in expressions typed in by
5422 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5423 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5426 The new directory `gdb/sparclite' contains a program that demonstrates
5427 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5429 * New native hosts supported
5431 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5432 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5434 * New targets supported
5436 AMD 29k family via UDI a29k-amd-udi or udi29k
5438 * New file formats supported
5440 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5441 HPUX core files, and SCO 3.2v2 core files.
5445 Attaching to processes now works again; thanks for the many bug reports.
5447 We have also stomped on a bunch of core dumps caused by
5448 printf_filtered("%s") problems.
5450 We eliminated a copyright problem on the rpc and ptrace header files
5451 for VxWorks, which was discovered at the last minute during the 4.7
5452 release. You should now be able to build a VxWorks GDB.
5454 You can now interrupt gdb while an attached process is running. This
5455 will cause the attached process to stop, and give control back to GDB.
5457 We fixed problems caused by using too many file descriptors
5458 for reading symbols from object files and libraries. This was
5459 especially a problem for programs that used many (~100) shared
5462 The `step' command now only enters a subroutine if there is line number
5463 information for the subroutine. Otherwise it acts like the `next'
5464 command. Previously, `step' would enter subroutines if there was
5465 any debugging information about the routine. This avoids problems
5466 when using `cc -g1' on MIPS machines.
5468 * Internal improvements
5470 GDB's internal interfaces have been improved to make it easier to support
5471 debugging of multiple languages in the future.
5473 GDB now uses a common structure for symbol information internally.
5474 Minimal symbols (derived from linkage symbols in object files), partial
5475 symbols (from a quick scan of debug information), and full symbols
5476 contain a common subset of information, making it easier to write
5477 shared code that handles any of them.
5479 * New command line options
5481 We now accept --silent as an alias for --quiet.
5485 The memory-mapped-malloc library is now licensed under the GNU Library
5486 General Public License.
5488 *** Changes in GDB-4.7:
5490 * Host/native/target split
5492 GDB has had some major internal surgery to untangle the support for
5493 hosts and remote targets. Now, when you configure GDB for a remote
5494 target, it will no longer load in all of the support for debugging
5495 local programs on the host. When fully completed and tested, this will
5496 ensure that arbitrary host/target combinations are possible.
5498 The primary conceptual shift is to separate the non-portable code in
5499 GDB into three categories. Host specific code is required any time GDB
5500 is compiled on that host, regardless of the target. Target specific
5501 code relates to the peculiarities of the target, but can be compiled on
5502 any host. Native specific code is everything else: it can only be
5503 built when the host and target are the same system. Child process
5504 handling and core file support are two common `native' examples.
5506 GDB's use of /proc for controlling Unix child processes is now cleaner.
5507 It has been split out into a single module under the `target_ops' vector,
5508 plus two native-dependent functions for each system that uses /proc.
5510 * New hosts supported
5512 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5513 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5514 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5516 * New targets supported
5518 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5519 68030 and CPU32 m68030-*-*, m68332-*-*
5521 * New native hosts supported
5523 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5524 (386bsd is not well tested yet)
5525 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5527 * New file formats supported
5529 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5530 supports reading of `a.out.adobe' object files, which are an a.out
5531 format extended with minimal information about multiple sections.
5535 `show copying' is the same as the old `info copying'.
5536 `show warranty' is the same as `info warrantee'.
5537 These were renamed for consistency. The old commands continue to work.
5539 `info handle' is a new alias for `info signals'.
5541 You can now define pre-command hooks, which attach arbitrary command
5542 scripts to any command. The commands in the hook will be executed
5543 prior to the user's command. You can also create a hook which will be
5544 executed whenever the program stops. See gdb.texinfo.
5548 We now deal with Cfront style name mangling, and can even extract type
5549 info from mangled symbols. GDB can automatically figure out which
5550 symbol mangling style your C++ compiler uses.
5552 Calling of methods and virtual functions has been improved as well.
5556 The crash that occured when debugging Sun Ansi-C compiled binaries is
5557 fixed. This was due to mishandling of the extra N_SO stabs output
5560 We also finally got Ultrix 4.2 running in house, and fixed core file
5561 support, with help from a dozen people on the net.
5563 John M. Farrell discovered that the reason that single-stepping was so
5564 slow on all of the Mips based platforms (primarily SGI and DEC) was
5565 that we were trying to demangle and lookup a symbol used for internal
5566 purposes on every instruction that was being stepped through. Changing
5567 the name of that symbol so that it couldn't be mistaken for a C++
5568 mangled symbol sped things up a great deal.
5570 Rich Pixley sped up symbol lookups in general by getting much smarter
5571 about when C++ symbol mangling is necessary. This should make symbol
5572 completion (TAB on the command line) much faster. It's not as fast as
5573 we'd like, but it's significantly faster than gdb-4.6.
5577 A new user controllable variable 'call_scratch_address' can
5578 specify the location of a scratch area to be used when GDB
5579 calls a function in the target. This is necessary because the
5580 usual method of putting the scratch area on the stack does not work
5581 in systems that have separate instruction and data spaces.
5583 We integrated changes to support the 29k UDI (Universal Debugger
5584 Interface), but discovered at the last minute that we didn't have all
5585 of the appropriate copyright paperwork. We are working with AMD to
5586 resolve this, and hope to have it available soon.
5590 We have sped up the remote serial line protocol, especially for targets
5591 with lots of registers. It now supports a new `expedited status' ('T')
5592 message which can be used in place of the existing 'S' status message.
5593 This allows the remote stub to send only the registers that GDB
5594 needs to make a quick decision about single-stepping or conditional
5595 breakpoints, eliminating the need to fetch the entire register set for
5596 each instruction being stepped through.
5598 The GDB remote serial protocol now implements a write-through cache for
5599 registers, only re-reading the registers if the target has run.
5601 There is also a new remote serial stub for SPARC processors. You can
5602 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5603 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5604 processor with a serial port.
5608 Configure.in files have become much easier to read and modify. A new
5609 `table driven' format makes it more obvious what configurations are
5610 supported, and what files each one uses.
5614 There is a new opcodes library which will eventually contain all of the
5615 disassembly routines and opcode tables. At present, it only contains
5616 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5617 disassembler (binutils/objdump) to share these routines.
5619 The libiberty library is now copylefted under the GNU Library General
5620 Public License. This allows more liberal use, and was done so libg++
5621 can use it. This makes no difference to GDB, since the Library License
5622 grants all the rights from the General Public License.
5626 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5627 reference to the stabs symbol info used by the debugger. It is (as far
5628 as we know) the only published document on this fascinating topic. We
5629 encourage you to read it, compare it to the stabs information on your
5630 system, and send improvements on the document in general (to
5631 bug-gdb@prep.ai.mit.edu).
5633 And, of course, many bugs have been fixed.
5636 *** Changes in GDB-4.6:
5638 * Better support for C++ function names
5640 GDB now accepts as input the "demangled form" of C++ overloaded function
5641 names and member function names, and can do command completion on such names
5642 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5643 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5644 Make use of command completion, it is your friend.
5646 GDB also now accepts a variety of C++ mangled symbol formats. They are
5647 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5648 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5649 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5650 for the list of formats.
5652 * G++ symbol mangling problem
5654 Recent versions of gcc have a bug in how they emit debugging information for
5655 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5656 directory) can be applied to gcc to fix the problem. Alternatively, if you
5657 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5658 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5659 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5662 * New 'maintenance' command
5664 All of the commands related to hacking GDB internals have been moved out of
5665 the main command set, and now live behind the 'maintenance' command. This
5666 can also be abbreviated as 'mt'. The following changes were made:
5668 dump-me -> maintenance dump-me
5669 info all-breakpoints -> maintenance info breakpoints
5670 printmsyms -> maintenance print msyms
5671 printobjfiles -> maintenance print objfiles
5672 printpsyms -> maintenance print psymbols
5673 printsyms -> maintenance print symbols
5675 The following commands are new:
5677 maintenance demangle Call internal GDB demangler routine to
5678 demangle a C++ link name and prints the result.
5679 maintenance print type Print a type chain for a given symbol
5681 * Change to .gdbinit file processing
5683 We now read the $HOME/.gdbinit file before processing the argv arguments
5684 (e.g. reading symbol files or core files). This allows global parameters to
5685 be set, which will apply during the symbol reading. The ./.gdbinit is still
5686 read after argv processing.
5688 * New hosts supported
5690 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5692 GNU/Linux support i386-unknown-linux or linux
5694 We are also including code to support the HP/PA running BSD and HPUX. This
5695 is almost guaranteed not to work, as we didn't have time to test or build it
5696 for this release. We are including it so that the more adventurous (or
5697 masochistic) of you can play with it. We also had major problems with the
5698 fact that the compiler that we got from HP doesn't support the -g option.
5701 * New targets supported
5703 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5705 * More smarts about finding #include files
5707 GDB now remembers the compilation directory for all include files, and for
5708 all files from which C is generated (like yacc and lex sources). This
5709 greatly improves GDB's ability to find yacc/lex sources, and include files,
5710 especially if you are debugging your program from a directory different from
5711 the one that contains your sources.
5713 We also fixed a bug which caused difficulty with listing and setting
5714 breakpoints in include files which contain C code. (In the past, you had to
5715 try twice in order to list an include file that you hadn't looked at before.)
5717 * Interesting infernals change
5719 GDB now deals with arbitrary numbers of sections, where the symbols for each
5720 section must be relocated relative to that section's landing place in the
5721 target's address space. This work was needed to support ELF with embedded
5722 stabs used by Solaris-2.0.
5724 * Bug fixes (of course!)
5726 There have been loads of fixes for the following things:
5727 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5728 i960, stabs, DOS(GO32), procfs, etc...
5730 See the ChangeLog for details.
5732 *** Changes in GDB-4.5:
5734 * New machines supported (host and target)
5736 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5738 SGI Irix-4.x mips-sgi-irix4 or iris4
5740 * New malloc package
5742 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5743 Mmalloc is capable of handling mutiple heaps of memory. It is also
5744 capable of saving a heap to a file, and then mapping it back in later.
5745 This can be used to greatly speedup the startup of GDB by using a
5746 pre-parsed symbol table which lives in a mmalloc managed heap. For
5747 more details, please read mmalloc/mmalloc.texi.
5751 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5752 'help info proc' for details.
5754 * MIPS ecoff symbol table format
5756 The code that reads MIPS symbol table format is now supported on all hosts.
5757 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5760 * File name changes for MS-DOS
5762 Many files in the config directories have been renamed to make it easier to
5763 support GDB on MS-DOSe systems (which have very restrictive file name
5764 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5765 environment) is close to working but has some remaining problems. Note
5766 that debugging of DOS programs is not supported, due to limitations
5767 in the ``operating system'', but it can be used to host cross-debugging.
5769 * Cross byte order fixes
5771 Many fixes have been made to support cross debugging of Sparc and MIPS
5772 targets from hosts whose byte order differs.
5774 * New -mapped and -readnow options
5776 If memory-mapped files are available on your system through the 'mmap'
5777 system call, you can use the -mapped option on the `file' or
5778 `symbol-file' commands to cause GDB to write the symbols from your
5779 program into a reusable file. If the program you are debugging is
5780 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5781 Future GDB debugging sessions will notice the presence of this file,
5782 and will quickly map in symbol information from it, rather than reading
5783 the symbol table from the executable program. Using the '-mapped'
5784 option in a GDB `file' or `symbol-file' command has the same effect as
5785 starting GDB with the '-mapped' command-line option.
5787 You can cause GDB to read the entire symbol table immediately by using
5788 the '-readnow' option with any of the commands that load symbol table
5789 information (or on the GDB command line). This makes the command
5790 slower, but makes future operations faster.
5792 The -mapped and -readnow options are typically combined in order to
5793 build a `fred.syms' file that contains complete symbol information.
5794 A simple GDB invocation to do nothing but build a `.syms' file for future
5797 gdb -batch -nx -mapped -readnow programname
5799 The `.syms' file is specific to the host machine on which GDB is run.
5800 It holds an exact image of GDB's internal symbol table. It cannot be
5801 shared across multiple host platforms.
5803 * longjmp() handling
5805 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5806 siglongjmp() without losing control. This feature has not yet been ported to
5807 all systems. It currently works on many 386 platforms, all MIPS-based
5808 platforms (SGI, DECstation, etc), and Sun3/4.
5812 Preliminary work has been put in to support the new Solaris OS from Sun. At
5813 this time, it can control and debug processes, but it is not capable of
5818 As always, many many bug fixes. The major areas were with g++, and mipsread.
5819 People using the MIPS-based platforms should experience fewer mysterious
5820 crashes and trashed symbol tables.
5822 *** Changes in GDB-4.4:
5824 * New machines supported (host and target)
5826 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5828 BSD Reno on Vax vax-dec-bsd
5829 Ultrix on Vax vax-dec-ultrix
5831 * New machines supported (target)
5833 AMD 29000 embedded, using EBMON a29k-none-none
5837 GDB continues to improve its handling of C++. `References' work better.
5838 The demangler has also been improved, and now deals with symbols mangled as
5839 per the Annotated C++ Reference Guide.
5841 GDB also now handles `stabs' symbol information embedded in MIPS
5842 `ecoff' symbol tables. Since the ecoff format was not easily
5843 extensible to handle new languages such as C++, this appeared to be a
5844 good way to put C++ debugging info into MIPS binaries. This option
5845 will be supported in the GNU C compiler, version 2, when it is
5848 * New features for SVR4
5850 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5851 shared libraries. Debugging dynamically linked programs should present
5852 only minor differences from debugging statically linked programs.
5854 The `info proc' command will print out information about any process
5855 on an SVR4 system (including the one you are debugging). At the moment,
5856 it prints the address mappings of the process.
5858 If you bring up GDB on another SVR4 system, please send mail to
5859 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5861 * Better dynamic linking support in SunOS
5863 Reading symbols from shared libraries which contain debugging symbols
5864 now works properly. However, there remain issues such as automatic
5865 skipping of `transfer vector' code during function calls, which
5866 make it harder to debug code in a shared library, than to debug the
5867 same code linked statically.
5871 GDB is now using the latest `getopt' routines from the FSF. This
5872 version accepts the -- prefix for options with long names. GDB will
5873 continue to accept the old forms (-option and +option) as well.
5874 Various single letter abbreviations for options have been explicity
5875 added to the option table so that they won't get overshadowed in the
5876 future by other options that begin with the same letter.
5880 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5881 Many assorted bugs have been handled. Many more remain to be handled.
5882 See the various ChangeLog files (primarily in gdb and bfd) for details.
5885 *** Changes in GDB-4.3:
5887 * New machines supported (host and target)
5889 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5890 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5891 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5893 * Almost SCO Unix support
5895 We had hoped to support:
5896 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5897 (except for core file support), but we discovered very late in the release
5898 that it has problems with process groups that render gdb unusable. Sorry
5899 about that. I encourage people to fix it and post the fixes.
5901 * Preliminary ELF and DWARF support
5903 GDB can read ELF object files on System V Release 4, and can handle
5904 debugging records for C, in DWARF format, in ELF files. This support
5905 is preliminary. If you bring up GDB on another SVR4 system, please
5906 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5911 GDB now uses the latest `readline' library. One user-visible change
5912 is that two tabs will list possible command completions, which previously
5913 required typing M-? (meta-question mark, or ESC ?).
5917 The `stepi' bug that many of you noticed has been squashed.
5918 Many bugs in C++ have been handled. Many more remain to be handled.
5919 See the various ChangeLog files (primarily in gdb and bfd) for details.
5921 * State of the MIPS world (in case you wondered):
5923 GDB can understand the symbol tables emitted by the compilers
5924 supplied by most vendors of MIPS-based machines, including DEC. These
5925 symbol tables are in a format that essentially nobody else uses.
5927 Some versions of gcc come with an assembler post-processor called
5928 mips-tfile. This program is required if you want to do source-level
5929 debugging of gcc-compiled programs. I believe FSF does not ship
5930 mips-tfile with gcc version 1, but it will eventually come with gcc
5933 Debugging of g++ output remains a problem. g++ version 1.xx does not
5934 really support it at all. (If you're lucky, you should be able to get
5935 line numbers and stack traces to work, but no parameters or local
5936 variables.) With some work it should be possible to improve the
5939 When gcc version 2 is released, you will have somewhat better luck.
5940 However, even then you will get confusing results for inheritance and
5943 We will eventually provide full debugging of g++ output on
5944 DECstations. This will probably involve some kind of stabs-in-ecoff
5945 encapulation, but the details have not been worked out yet.
5948 *** Changes in GDB-4.2:
5950 * Improved configuration
5952 Only one copy of `configure' exists now, and it is not self-modifying.
5953 Porting BFD is simpler.
5957 The `step' and `next' commands now only stop at the first instruction
5958 of a source line. This prevents the multiple stops that used to occur
5959 in switch statements, for-loops, etc. `Step' continues to stop if a
5960 function that has debugging information is called within the line.
5964 Lots of small bugs fixed. More remain.
5966 * New host supported (not target)
5968 Intel 386 PC clone running Mach i386-none-mach
5971 *** Changes in GDB-4.1:
5973 * Multiple source language support
5975 GDB now has internal scaffolding to handle several source languages.
5976 It determines the type of each source file from its filename extension,
5977 and will switch expression parsing and number formatting to match the
5978 language of the function in the currently selected stack frame.
5979 You can also specifically set the language to be used, with
5980 `set language c' or `set language modula-2'.
5984 GDB now has preliminary support for the GNU Modula-2 compiler,
5985 currently under development at the State University of New York at
5986 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5987 continue through the fall of 1991 and into 1992.
5989 Other Modula-2 compilers are currently not supported, and attempting to
5990 debug programs compiled with them will likely result in an error as the
5991 symbol table is read. Feel free to work on it, though!
5993 There are hooks in GDB for strict type checking and range checking,
5994 in the `Modula-2 philosophy', but they do not currently work.
5998 GDB can now write to executable and core files (e.g. patch
5999 a variable's value). You must turn this switch on, specify
6000 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6001 by assigning a new value to a variable. Modifications take
6004 * Automatic SunOS shared library reading
6006 When you run your program, GDB automatically determines where its
6007 shared libraries (if any) have been loaded, and reads their symbols.
6008 The `share' command is no longer needed. This also works when
6009 examining core files.
6013 You can specify the number of lines that the `list' command shows.
6016 * New machines supported (host and target)
6018 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6019 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6020 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6022 * New hosts supported (not targets)
6024 IBM RT/PC: romp-ibm-aix or rtpc
6026 * New targets supported (not hosts)
6028 AMD 29000 embedded with COFF a29k-none-coff
6029 AMD 29000 embedded with a.out a29k-none-aout
6030 Ultracomputer remote kernel debug a29k-nyu-kern
6032 * New remote interfaces
6038 *** Changes in GDB-4.0:
6042 Wide output is wrapped at good places to make the output more readable.
6044 Gdb now supports cross-debugging from a host machine of one type to a
6045 target machine of another type. Communication with the target system
6046 is over serial lines. The ``target'' command handles connecting to the
6047 remote system; the ``load'' command will download a program into the
6048 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6049 also supports debugging of realtime processes running under VxWorks,
6050 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6051 stub on the target system.
6053 New CPUs supported include the AMD 29000 and Intel 960.
6055 GDB now reads object files and symbol tables via a ``binary file''
6056 library, which allows a single copy of GDB to debug programs of multiple
6057 object file types such as a.out and coff.
6059 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6060 refcard.dvi and refcard.ps are available to format it).
6063 * Control-Variable user interface simplified
6065 All variables that control the operation of the debugger can be set
6066 by the ``set'' command, and displayed by the ``show'' command.
6068 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6069 ``Show prompt'' produces the response:
6070 Gdb's prompt is new-gdb=>.
6072 What follows are the NEW set commands. The command ``help set'' will
6073 print a complete list of old and new set commands. ``help set FOO''
6074 will give a longer description of the variable FOO. ``show'' will show
6075 all of the variable descriptions and their current settings.
6077 confirm on/off: Enables warning questions for operations that are
6078 hard to recover from, e.g. rerunning the program while
6079 it is already running. Default is ON.
6081 editing on/off: Enables EMACS style command line editing
6082 of input. Previous lines can be recalled with
6083 control-P, the current line can be edited with control-B,
6084 you can search for commands with control-R, etc.
6087 history filename NAME: NAME is where the gdb command history
6088 will be stored. The default is .gdb_history,
6089 or the value of the environment variable
6092 history size N: The size, in commands, of the command history. The
6093 default is 256, or the value of the environment variable
6096 history save on/off: If this value is set to ON, the history file will
6097 be saved after exiting gdb. If set to OFF, the
6098 file will not be saved. The default is OFF.
6100 history expansion on/off: If this value is set to ON, then csh-like
6101 history expansion will be performed on
6102 command line input. The default is OFF.
6104 radix N: Sets the default radix for input and output. It can be set
6105 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6106 in the current radix, so "set radix 10" is always a no-op.
6108 height N: This integer value is the number of lines on a page. Default
6109 is 24, the current `stty rows'' setting, or the ``li#''
6110 setting from the termcap entry matching the environment
6113 width N: This integer value is the number of characters on a line.
6114 Default is 80, the current `stty cols'' setting, or the ``co#''
6115 setting from the termcap entry matching the environment
6118 Note: ``set screensize'' is obsolete. Use ``set height'' and
6119 ``set width'' instead.
6121 print address on/off: Print memory addresses in various command displays,
6122 such as stack traces and structure values. Gdb looks
6123 more ``symbolic'' if you turn this off; it looks more
6124 ``machine level'' with it on. Default is ON.
6126 print array on/off: Prettyprint arrays. New convenient format! Default
6129 print demangle on/off: Print C++ symbols in "source" form if on,
6132 print asm-demangle on/off: Same, for assembler level printouts
6135 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6138 * Support for Epoch Environment.
6140 The epoch environment is a version of Emacs v18 with windowing. One
6141 new command, ``inspect'', is identical to ``print'', except that if you
6142 are running in the epoch environment, the value is printed in its own
6146 * Support for Shared Libraries
6148 GDB can now debug programs and core files that use SunOS shared libraries.
6149 Symbols from a shared library cannot be referenced
6150 before the shared library has been linked with the program (this
6151 happens after you type ``run'' and before the function main() is entered).
6152 At any time after this linking (including when examining core files
6153 from dynamically linked programs), gdb reads the symbols from each
6154 shared library when you type the ``sharedlibrary'' command.
6155 It can be abbreviated ``share''.
6157 sharedlibrary REGEXP: Load shared object library symbols for files
6158 matching a unix regular expression. No argument
6159 indicates to load symbols for all shared libraries.
6161 info sharedlibrary: Status of loaded shared libraries.
6166 A watchpoint stops execution of a program whenever the value of an
6167 expression changes. Checking for this slows down execution
6168 tremendously whenever you are in the scope of the expression, but is
6169 quite useful for catching tough ``bit-spreader'' or pointer misuse
6170 problems. Some machines such as the 386 have hardware for doing this
6171 more quickly, and future versions of gdb will use this hardware.
6173 watch EXP: Set a watchpoint (breakpoint) for an expression.
6175 info watchpoints: Information about your watchpoints.
6177 delete N: Deletes watchpoint number N (same as breakpoints).
6178 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6179 enable N: Re-enables watchpoint number N (same as breakpoints).
6182 * C++ multiple inheritance
6184 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6187 * C++ exception handling
6189 Gdb now supports limited C++ exception handling. Besides the existing
6190 ability to breakpoint on an exception handler, gdb can breakpoint on
6191 the raising of an exception (before the stack is peeled back to the
6194 catch FOO: If there is a FOO exception handler in the dynamic scope,
6195 set a breakpoint to catch exceptions which may be raised there.
6196 Multiple exceptions (``catch foo bar baz'') may be caught.
6198 info catch: Lists all exceptions which may be caught in the
6199 current stack frame.
6202 * Minor command changes
6204 The command ``call func (arg, arg, ...)'' now acts like the print
6205 command, except it does not print or save a value if the function's result
6206 is void. This is similar to dbx usage.
6208 The ``up'' and ``down'' commands now always print the frame they end up
6209 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6210 frames without printing.
6212 * New directory command
6214 'dir' now adds directories to the FRONT of the source search path.
6215 The path starts off empty. Source files that contain debug information
6216 about the directory in which they were compiled can be found even
6217 with an empty path; Sun CC and GCC include this information. If GDB can't
6218 find your source file in the current directory, type "dir .".
6220 * Configuring GDB for compilation
6222 For normal use, type ``./configure host''. See README or gdb.texinfo
6225 GDB now handles cross debugging. If you are remotely debugging between
6226 two different machines, type ``./configure host -target=targ''.
6227 Host is the machine where GDB will run; targ is the machine
6228 where the program that you are debugging will run.
projects / external / binutils.git / blob