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.
29 Control display of debugging info regarding bfd caching.
31 set remote multiprocess-extensions-packet
32 show remote multiprocess-extensions-packet
33 Set/show the use of the remote protocol multiprocess extensions.
35 * The "disassemble" command accepts a new modifier: /s.
36 It prints mixed source+disassembly like /m with two differences:
37 - disassembled instructions are now printed in program order, and
38 - and source for all relevant files is now printed.
39 The "/m" option is now considered deprecated: its "source-centric"
40 output hasn't proved useful in practice.
42 * Support for various ROM monitors has been removed:
44 target dbug dBUG ROM monitor for Motorola ColdFire
45 target picobug Motorola picobug monitor
46 target dink32 DINK32 ROM monitor for PowerPC
47 target m32r Renesas M32R/D ROM monitor
48 target mon2000 mon2000 ROM monitor
49 target ppcbug PPCBUG ROM monitor for PowerPC
51 *** Changes in GDB 7.10
53 * Support for process record-replay and reverse debugging on aarch64*-linux*
54 targets has been added. GDB now supports recording of A64 instruction set
55 including advance SIMD instructions.
57 * Support for Sun's version of the "stabs" debug file format has been removed.
59 * GDB now honors the content of the file /proc/PID/coredump_filter
60 (PID is the process ID) on GNU/Linux systems. This file can be used
61 to specify the types of memory mappings that will be included in a
62 corefile. For more information, please refer to the manual page of
63 "core(5)". GDB also has a new command: "set use-coredump-filter
64 on|off". It allows to set whether GDB will read the content of the
65 /proc/PID/coredump_filter file when generating a corefile.
67 * The "info os" command on GNU/Linux can now display information on
69 "info os cpus" Listing of all cpus/cores on the system
71 * GDB has two new commands: "set serial parity odd|even|none" and
72 "show serial parity". These allows to set or show parity for the
75 * The "info source" command now displays the producer string if it was
76 present in the debug info. This typically includes the compiler version
77 and may include things like its command line arguments.
79 * The "info dll", an alias of the "info sharedlibrary" command,
80 is now available on all platforms.
82 * Directory names supplied to the "set sysroot" commands may be
83 prefixed with "target:" to tell GDB to access shared libraries from
84 the target system, be it local or remote. This replaces the prefix
85 "remote:". The default sysroot has been changed from "" to
86 "target:". "remote:" is automatically converted to "target:" for
87 backward compatibility.
89 * The system root specified by "set sysroot" will be prepended to the
90 filename of the main executable (if reported to GDB as absolute by
91 the operating system) when starting processes remotely, and when
92 attaching to already-running local or remote processes.
94 * GDB now supports automatic location and retrieval of executable
95 files from remote targets. Remote debugging can now be initiated
96 using only a "target remote" or "target extended-remote" command
97 (no "set sysroot" or "file" commands are required). See "New remote
100 * The "dump" command now supports verilog hex format.
102 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
104 * On GNU/Linux, GDB and gdbserver are now able to access executable
105 and shared library files without a "set sysroot" command when
106 attaching to processes running in different mount namespaces from
107 the debugger. This makes it possible to attach to processes in
108 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
109 See "New remote packets" below.
111 * The "tui reg" command now provides completion for all of the
112 available register groups, including target specific groups.
114 * The HISTSIZE environment variable is no longer read when determining
115 the size of GDB's command history. GDB now instead reads the dedicated
116 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
117 disables truncation of command history. Non-numeric values of GDBHISTSIZE
122 ** Memory ports can now be unbuffered.
126 ** gdb.Objfile objects have a new attribute "username",
127 which is the name of the objfile as specified by the user,
128 without, for example, resolving symlinks.
129 ** You can now write frame unwinders in Python.
130 ** gdb.Type objects have a new method "optimized_out",
131 returning optimized out gdb.Value instance of this type.
132 ** gdb.Value objects have new methods "reference_value" and
133 "const_value" which return a reference to the value and a
134 "const" version of the value respectively.
138 maint print symbol-cache
139 Print the contents of the symbol cache.
141 maint print symbol-cache-statistics
142 Print statistics of symbol cache usage.
144 maint flush-symbol-cache
145 Flush the contents of the symbol cache.
147 maint set target-non-stop (on|off|auto)
148 maint show target-non-stop
149 Control whether GDB targets always operate in non-stop mode even if
150 "set non-stop" is "off". The default is "auto", meaning non-stop
151 mode is enabled if supported by the target.
155 Start branch trace recording using Branch Trace Store (BTS) format.
158 Evaluate expression by using the compiler and print result.
162 Explicit commands for enabling and disabling tui mode.
165 set mpx bound on i386 and amd64
166 Support for bound table investigation on Intel(R) MPX enabled applications.
170 Start branch trace recording using Intel(R) Processor Trace format.
173 Print information about branch tracing internals.
175 maint btrace packet-history
176 Print the raw branch tracing data.
178 maint btrace clear-packet-history
179 Discard the stored raw branch tracing data.
182 Discard all branch tracing data. It will be fetched and processed
183 anew by the next "record" command.
188 Renamed from "set debug dwarf2-die".
190 Renamed from "show debug dwarf2-die".
193 Renamed from "set debug dwarf2-read".
194 show debug dwarf-read
195 Renamed from "show debug dwarf2-read".
197 maint set dwarf always-disassemble
198 Renamed from "maint set dwarf2 always-disassemble".
199 maint show dwarf always-disassemble
200 Renamed from "maint show dwarf2 always-disassemble".
202 maint set dwarf max-cache-age
203 Renamed from "maint set dwarf2 max-cache-age".
204 maint show dwarf max-cache-age
205 Renamed from "maint show dwarf2 max-cache-age".
208 show debug dwarf-line
209 Control display of debugging info regarding DWARF line processing.
213 Set the maximum number of candidates to be considered during
214 completion. The default value is 200. This limit allows GDB
215 to avoid generating large completion lists, the computation of
216 which can cause the debugger to become temporarily unresponsive.
218 set history remove-duplicates
219 show history remove-duplicates
220 Control the removal of duplicate history entries.
222 maint set symbol-cache-size
223 maint show symbol-cache-size
224 Control the size of the symbol cache.
226 set|show record btrace bts buffer-size
227 Set and show the size of the ring buffer used for branch tracing in
229 The obtained size may differ from the requested size. Use "info
230 record" to see the obtained buffer size.
232 set debug linux-namespaces
233 show debug linux-namespaces
234 Control display of debugging info regarding Linux namespaces.
236 set|show record btrace pt buffer-size
237 Set and show the size of the ring buffer used for branch tracing in
238 Intel(R) Processor Trace format.
239 The obtained size may differ from the requested size. Use "info
240 record" to see the obtained buffer size.
242 maint set|show btrace pt skip-pad
243 Set and show whether PAD packets are skipped when computing the
246 * The command 'thread apply all' can now support new option '-ascending'
247 to call its specified command for all threads in ascending order.
249 * Python/Guile scripting
251 ** GDB now supports auto-loading of Python/Guile scripts contained in the
252 special section named `.debug_gdb_scripts'.
256 qXfer:btrace-conf:read
257 Return the branch trace configuration for the current thread.
259 Qbtrace-conf:bts:size
260 Set the requested ring buffer size for branch tracing in BTS format.
263 Enable Intel(R) Procesor Trace-based branch tracing for the current
264 process. The remote stub reports support for this packet to GDB's
268 Set the requested ring buffer size for branch tracing in Intel(R) Processor
272 Indicates a memory breakpoint instruction was executed, irrespective
273 of whether it was GDB that planted the breakpoint or the breakpoint
274 is hardcoded in the program. This is required for correct non-stop
278 Indicates the target stopped for a hardware breakpoint. This is
279 required for correct non-stop mode operation.
282 Return information about files on the remote system.
285 Return the full absolute name of the file that was executed to
286 create a process running on the remote system.
289 Select the filesystem on which vFile: operations with filename
290 arguments will operate. This is required for GDB to be able to
291 access files on remote targets where the remote stub does not
292 share a common filesystem with the inferior(s).
295 Indicates that a fork system call was executed.
298 Indicates that a vfork system call was executed.
300 vforkdone stop reason
301 Indicates that a vfork child of the specified process has executed
302 an exec or exit, allowing the vfork parent to resume execution.
304 fork-events and vfork-events features in qSupported
305 The qSupported packet allows GDB to request support for fork and
306 vfork events using new 'gdbfeatures' fork-events and vfork-events,
307 and the qSupported response can contain the corresponding
308 'stubfeatures'. Set and show commands can be used to display
309 whether these features are enabled.
311 * Extended-remote fork events
313 ** GDB now has support for fork events on extended-remote Linux
314 targets. For targets with Linux kernels 2.5.60 and later, this
315 enables follow-fork-mode and detach-on-fork for both fork and
316 vfork, as well as fork and vfork catchpoints.
318 * The info record command now shows the recording format and the
319 branch tracing configuration for the current thread when using
320 the btrace record target.
321 For the BTS format, it shows the ring buffer size.
323 * GDB now has support for DTrace USDT (Userland Static Defined
324 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
326 * GDB now supports access to vector registers on S/390 GNU/Linux
329 * Removed command line options
331 -xdb HP-UX XDB compatibility mode.
333 * Removed targets and native configurations
335 HP/PA running HP-UX hppa*-*-hpux*
336 Itanium running HP-UX ia64-*-hpux*
338 * New configure options
341 This configure option allows the user to build GDB with support for
342 Intel(R) Processor Trace (default: auto). This requires libipt.
344 --with-libipt-prefix=PATH
345 Specify the path to the version of libipt that GDB should use.
346 $PATH/include should contain the intel-pt.h header and
347 $PATH/lib should contain the libipt.so library.
349 *** Changes in GDB 7.9.1
353 ** Xmethods can now specify a result type.
355 *** Changes in GDB 7.9
357 * GDB now supports hardware watchpoints on x86 GNU Hurd.
361 ** You can now access frame registers from Python scripts.
362 ** New attribute 'producer' for gdb.Symtab objects.
363 ** gdb.Objfile objects have a new attribute "progspace",
364 which is the gdb.Progspace object of the containing program space.
365 ** gdb.Objfile objects have a new attribute "owner".
366 ** gdb.Objfile objects have a new attribute "build_id",
367 which is the build ID generated when the file was built.
368 ** gdb.Objfile objects have a new method "add_separate_debug_file".
369 ** A new event "gdb.clear_objfiles" has been added, triggered when
370 selecting a new file to debug.
371 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
372 ** New function gdb.lookup_objfile.
374 New events which are triggered when GDB modifies the state of the
377 ** gdb.events.inferior_call_pre: Function call is about to be made.
378 ** gdb.events.inferior_call_post: Function call has just been made.
379 ** gdb.events.memory_changed: A memory location has been altered.
380 ** gdb.events.register_changed: A register has been altered.
382 * New Python-based convenience functions:
384 ** $_caller_is(name [, number_of_frames])
385 ** $_caller_matches(regexp [, number_of_frames])
386 ** $_any_caller_is(name [, number_of_frames])
387 ** $_any_caller_matches(regexp [, number_of_frames])
389 * GDB now supports the compilation and injection of source code into
390 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
391 to compile the source code to object code, and if successful, inject
392 and execute that code within the current context of the inferior.
393 Currently the C language is supported. The commands used to
394 interface with this new feature are:
396 compile code [-raw|-r] [--] [source code]
397 compile file [-raw|-r] filename
401 demangle [-l language] [--] name
402 Demangle "name" in the specified language, or the current language
403 if elided. This command is renamed from the "maint demangle" command.
404 The latter is kept as a no-op to avoid "maint demangle" being interpreted
405 as "maint demangler-warning".
407 queue-signal signal-name-or-number
408 Queue a signal to be delivered to the thread when it is resumed.
410 add-auto-load-scripts-directory directory
411 Add entries to the list of directories from which to load auto-loaded
414 maint print user-registers
415 List all currently available "user" registers.
417 compile code [-r|-raw] [--] [source code]
418 Compile, inject, and execute in the inferior the executable object
419 code produced by compiling the provided source code.
421 compile file [-r|-raw] filename
422 Compile and inject into the inferior the executable object code
423 produced by compiling the source code stored in the filename
426 * On resume, GDB now always passes the signal the program had stopped
427 for to the thread the signal was sent to, even if the user changed
428 threads before resuming. Previously GDB would often (but not
429 always) deliver the signal to the thread that happens to be current
432 * Conversely, the "signal" command now consistently delivers the
433 requested signal to the current thread. GDB now asks for
434 confirmation if the program had stopped for a signal and the user
435 switched threads meanwhile.
437 * "breakpoint always-inserted" modes "off" and "auto" merged.
439 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
440 won't remove breakpoints from the target until all threads stop,
441 even in non-stop mode. The "auto" mode has been removed, and "off"
442 is now the default mode.
446 set debug symbol-lookup
447 show debug symbol-lookup
448 Control display of debugging info regarding symbol lookup.
452 ** The -list-thread-groups command outputs an exit-code field for
453 inferiors that have exited.
457 MIPS SDE mips*-sde*-elf*
461 Support for these obsolete configurations has been removed.
463 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
464 SGI Irix-5.x mips-*-irix5*
465 SGI Irix-6.x mips-*-irix6*
466 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
467 VAX running Ultrix vax-*-ultrix*
469 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
470 and "assf"), have been removed. Use the "sharedlibrary" command, or
471 its alias "share", instead.
473 *** Changes in GDB 7.8
475 * New command line options
478 This is an alias for the --data-directory option.
480 * GDB supports printing and modifying of variable length automatic arrays
481 as specified in ISO C99.
483 * The ARM simulator now supports instruction level tracing
484 with or without disassembly.
488 GDB now has support for scripting using Guile. Whether this is
489 available is determined at configure time.
490 Guile version 2.0 or greater is required.
491 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
493 * New commands (for set/show, see "New options" below)
497 Invoke CODE by passing it to the Guile interpreter.
501 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
503 info auto-load guile-scripts [regexp]
504 Print the list of automatically loaded Guile scripts.
506 * The source command is now capable of sourcing Guile scripts.
507 This feature is dependent on the debugger being built with Guile support.
511 set print symbol-loading (off|brief|full)
512 show print symbol-loading
513 Control whether to print informational messages when loading symbol
514 information for a file. The default is "full", but when debugging
515 programs with large numbers of shared libraries the amount of output
518 set guile print-stack (none|message|full)
519 show guile print-stack
520 Show a stack trace when an error is encountered in a Guile script.
522 set auto-load guile-scripts (on|off)
523 show auto-load guile-scripts
524 Control auto-loading of Guile script files.
526 maint ada set ignore-descriptive-types (on|off)
527 maint ada show ignore-descriptive-types
528 Control whether the debugger should ignore descriptive types in Ada
529 programs. The default is not to ignore the descriptive types. See
530 the user manual for more details on descriptive types and the intended
531 usage of this option.
533 set auto-connect-native-target
535 Control whether GDB is allowed to automatically connect to the
536 native target for the run, attach, etc. commands when not connected
537 to any target yet. See also "target native" below.
539 set record btrace replay-memory-access (read-only|read-write)
540 show record btrace replay-memory-access
541 Control what memory accesses are allowed during replay.
543 maint set target-async (on|off)
544 maint show target-async
545 This controls whether GDB targets operate in synchronous or
546 asynchronous mode. Normally the default is asynchronous, if it is
547 available; but this can be changed to more easily debug problems
548 occurring only in synchronous mode.
550 set mi-async (on|off)
552 Control whether MI asynchronous mode is preferred. This supersedes
553 "set target-async" of previous GDB versions.
555 * "set target-async" is deprecated as a CLI option and is now an alias
556 for "set mi-async" (only puts MI into async mode).
558 * Background execution commands (e.g., "c&", "s&", etc.) are now
559 possible ``out of the box'' if the target supports them. Previously
560 the user would need to explicitly enable the possibility with the
561 "set target-async on" command.
563 * New features in the GDB remote stub, GDBserver
565 ** New option --debug-format=option1[,option2,...] allows one to add
566 additional text to each output. At present only timestamps
567 are supported: --debug-format=timestamps.
568 Timestamps can also be turned on with the
569 "monitor set debug-format timestamps" command from GDB.
571 * The 'record instruction-history' command now starts counting instructions
572 at one. This also affects the instruction ranges reported by the
573 'record function-call-history' command when given the /i modifier.
575 * The command 'record function-call-history' supports a new modifier '/c' to
576 indent the function names based on their call stack depth.
577 The fields for the '/i' and '/l' modifier have been reordered.
578 The source line range is now prefixed with 'at'.
579 The instruction range is now prefixed with 'inst'.
580 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
581 "record instruction-history" and "list" commands.
583 * The ranges given as arguments to the 'record function-call-history' and
584 'record instruction-history' commands are now inclusive.
586 * The btrace record target now supports the 'record goto' command.
587 For locations inside the execution trace, the back trace is computed
588 based on the information stored in the execution trace.
590 * The btrace record target supports limited reverse execution and replay.
591 The target does not record data and therefore does not allow reading
594 * The "catch syscall" command now works on s390*-linux* targets.
596 * The "compare-sections" command is no longer specific to target
597 remote. It now works with all targets.
599 * All native targets are now consistently called "native".
600 Consequently, the "target child", "target GNU", "target djgpp",
601 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
602 commands have been replaced with "target native". The QNX/NTO port
603 leaves the "procfs" target in place and adds a "native" target for
604 consistency with other ports. The impact on users should be minimal
605 as these commands previously either throwed an error, or were
606 no-ops. The target's name is visible in the output of the following
607 commands: "help target", "info target", "info files", "maint print
610 * The "target native" command now connects to the native target. This
611 can be used to launch native programs even when "set
612 auto-connect-native-target" is set to off.
614 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
616 * Support for Intel(R) AVX-512 registers on GNU/Linux.
617 Support displaying and modifying Intel(R) AVX-512 registers
618 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
622 qXfer:btrace:read's annex
623 The qXfer:btrace:read packet supports a new annex 'delta' to read
624 branch trace incrementally.
628 ** Valid Python operations on gdb.Value objects representing
629 structs/classes invoke the corresponding overloaded operators if
631 ** New `Xmethods' feature in the Python API. Xmethods are
632 additional methods or replacements for existing methods of a C++
633 class. This feature is useful for those cases where a method
634 defined in C++ source code could be inlined or optimized out by
635 the compiler, making it unavailable to GDB.
638 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
640 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
641 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
642 its alias "share", instead.
644 * The commands "set remotebaud" and "show remotebaud" are no longer
645 supported. Use "set serial baud" and "show serial baud" (respectively)
650 ** A new option "-gdb-set mi-async" replaces "-gdb-set
651 target-async". The latter is left as a deprecated alias of the
652 former for backward compatibility. If the target supports it,
653 CLI background execution commands are now always possible by
654 default, independently of whether the frontend stated a
655 preference for asynchronous execution with "-gdb-set mi-async".
656 Previously "-gdb-set target-async off" affected both MI execution
657 commands and CLI execution commands.
659 *** Changes in GDB 7.7
661 * Improved support for process record-replay and reverse debugging on
662 arm*-linux* targets. Support for thumb32 and syscall instruction
663 recording has been added.
665 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
667 * GDB now supports Fission DWP file format version 2.
668 http://gcc.gnu.org/wiki/DebugFission
670 * New convenience function "$_isvoid", to check whether an expression
671 is void. A void expression is an expression where the type of the
672 result is "void". For example, some convenience variables may be
673 "void" when evaluated (e.g., "$_exitcode" before the execution of
674 the program being debugged; or an undefined convenience variable).
675 Another example, when calling a function whose return type is
678 * The "maintenance print objfiles" command now takes an optional regexp.
680 * The "catch syscall" command now works on arm*-linux* targets.
682 * GDB now consistently shows "<not saved>" when printing values of
683 registers the debug info indicates have not been saved in the frame
684 and there's nowhere to retrieve them from
685 (callee-saved/call-clobbered registers):
690 (gdb) info registers rax
693 Before, the former would print "<optimized out>", and the latter
694 "*value not available*".
696 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
701 ** Frame filters and frame decorators have been added.
702 ** Temporary breakpoints are now supported.
703 ** Line tables representation has been added.
704 ** New attribute 'parent_type' for gdb.Field objects.
705 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
706 ** New attribute 'name' for gdb.Type objects.
710 Nios II ELF nios2*-*-elf
711 Nios II GNU/Linux nios2*-*-linux
712 Texas Instruments MSP430 msp430*-*-elf
714 * Removed native configurations
716 Support for these a.out NetBSD and OpenBSD obsolete configurations has
717 been removed. ELF variants of these configurations are kept supported.
719 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
720 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
721 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
722 i[34567]86-*-openbsd3.[0-3]
723 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
724 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
725 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
729 Like "catch throw", but catches a re-thrown exception.
731 Renamed from old "maint check-symtabs".
733 Perform consistency checks on symtabs.
735 Expand symtabs matching an optional regexp.
738 Display the details of GDB configure-time options.
740 maint set|show per-command
741 maint set|show per-command space
742 maint set|show per-command time
743 maint set|show per-command symtab
744 Enable display of per-command gdb resource usage.
746 remove-symbol-file FILENAME
747 remove-symbol-file -a ADDRESS
748 Remove a symbol file added via add-symbol-file. The file to remove
749 can be identified by its filename or by an address that lies within
750 the boundaries of this symbol file in memory.
753 info exceptions REGEXP
754 Display the list of Ada exceptions defined in the program being
755 debugged. If provided, only the exceptions whose names match REGEXP
760 set debug symfile off|on
762 Control display of debugging info regarding reading symbol files and
763 symbol tables within those files
765 set print raw frame-arguments
766 show print raw frame-arguments
767 Set/show whether to print frame arguments in raw mode,
768 disregarding any defined pretty-printers.
770 set remote trace-status-packet
771 show remote trace-status-packet
772 Set/show the use of remote protocol qTStatus packet.
776 Control display of debugging messages related to Nios II targets.
780 Control whether target-assisted range stepping is enabled.
782 set startup-with-shell
783 show startup-with-shell
784 Specifies whether Unix child processes are started via a shell or
789 Use the target memory cache for accesses to the code segment. This
790 improves performance of remote debugging (particularly disassembly).
792 * You can now use a literal value 'unlimited' for options that
793 interpret 0 or -1 as meaning "unlimited". E.g., "set
794 trace-buffer-size unlimited" is now an alias for "set
795 trace-buffer-size -1" and "set height unlimited" is now an alias for
798 * The "set debug symtab-create" debugging option of GDB has been changed to
799 accept a verbosity level. 0 means "off", 1 provides basic debugging
800 output, and values of 2 or greater provides more verbose output.
802 * New command-line options
804 Display the details of GDB configure-time options.
806 * The command 'tsave' can now support new option '-ctf' to save trace
807 buffer in Common Trace Format.
809 * Newly installed $prefix/bin/gcore acts as a shell interface for the
812 * GDB now implements the the C++ 'typeid' operator.
814 * The new convenience variable $_exception holds the exception being
815 thrown or caught at an exception-related catchpoint.
817 * The exception-related catchpoints, like "catch throw", now accept a
818 regular expression which can be used to filter exceptions by type.
820 * The new convenience variable $_exitsignal is automatically set to
821 the terminating signal number when the program being debugged dies
822 due to an uncaught signal.
826 ** All MI commands now accept an optional "--language" option.
827 Support for this feature can be verified by using the "-list-features"
828 command, which should contain "language-option".
830 ** The new command -info-gdb-mi-command allows the user to determine
831 whether a GDB/MI command is supported or not.
833 ** The "^error" result record returned when trying to execute an undefined
834 GDB/MI command now provides a variable named "code" whose content is the
835 "undefined-command" error code. Support for this feature can be verified
836 by using the "-list-features" command, which should contain
837 "undefined-command-error-code".
839 ** The -trace-save MI command can optionally save trace buffer in Common
842 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
844 ** The command -data-list-register-values now accepts an optional
845 "--skip-unavailable" option. When used, only the available registers
848 ** The new command -trace-frame-collected dumps collected variables,
849 computed expressions, tvars, memory and registers in a traceframe.
851 ** The commands -stack-list-locals, -stack-list-arguments and
852 -stack-list-variables now accept an option "--skip-unavailable".
853 When used, only the available locals or arguments are displayed.
855 ** The -exec-run command now accepts an optional "--start" option.
856 When used, the command follows the same semantics as the "start"
857 command, stopping the program's execution at the start of its
858 main subprogram. Support for this feature can be verified using
859 the "-list-features" command, which should contain
860 "exec-run-start-option".
862 ** The new commands -catch-assert and -catch-exceptions insert
863 catchpoints stopping the program when Ada exceptions are raised.
865 ** The new command -info-ada-exceptions provides the equivalent of
866 the new "info exceptions" command.
868 * New system-wide configuration scripts
869 A GDB installation now provides scripts suitable for use as system-wide
870 configuration scripts for the following systems:
874 * GDB now supports target-assigned range stepping with remote targets.
875 This improves the performance of stepping source lines by reducing
876 the number of control packets from/to GDB. See "New remote packets"
879 * GDB now understands the element 'tvar' in the XML traceframe info.
880 It has the id of the collected trace state variables.
882 * On S/390 targets that provide the transactional-execution feature,
883 the program interruption transaction diagnostic block (TDB) is now
884 represented as a number of additional "registers" in GDB.
890 The vCont packet supports a new 'r' action, that tells the remote
891 stub to step through an address range itself, without GDB
892 involvemement at each single-step.
894 qXfer:libraries-svr4:read's annex
895 The previously unused annex of the qXfer:libraries-svr4:read packet
896 is now used to support passing an argument list. The remote stub
897 reports support for this argument list to GDB's qSupported query.
898 The defined arguments are "start" and "prev", used to reduce work
899 necessary for library list updating, resulting in significant
902 * New features in the GDB remote stub, GDBserver
904 ** GDBserver now supports target-assisted range stepping. Currently
905 enabled on x86/x86_64 GNU/Linux targets.
907 ** GDBserver now adds element 'tvar' in the XML in the reply to
908 'qXfer:traceframe-info:read'. It has the id of the collected
909 trace state variables.
911 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
914 * New 'z' formatter for printing and examining memory, this displays the
915 value as hexadecimal zero padded on the left to the size of the type.
917 * GDB can now use Windows x64 unwinding data.
919 * The "set remotebaud" command has been replaced by "set serial baud".
920 Similarly, "show remotebaud" has been replaced by "show serial baud".
921 The "set remotebaud" and "show remotebaud" commands are still available
922 to provide backward compatibility with older versions of GDB.
924 *** Changes in GDB 7.6
926 * Target record has been renamed to record-full.
927 Record/replay is now enabled with the "record full" command.
928 This also affects settings that are associated with full record/replay
929 that have been moved from "set/show record" to "set/show record full":
931 set|show record full insn-number-max
932 set|show record full stop-at-limit
933 set|show record full memory-query
935 * A new record target "record-btrace" has been added. The new target
936 uses hardware support to record the control-flow of a process. It
937 does not support replaying the execution, but it implements the
938 below new commands for investigating the recorded execution log.
939 This new recording method can be enabled using:
943 The "record-btrace" target is only available on Intel Atom processors
944 and requires a Linux kernel 2.6.32 or later.
946 * Two new commands have been added for record/replay to give information
947 about the recorded execution without having to replay the execution.
948 The commands are only supported by "record btrace".
950 record instruction-history prints the execution history at
951 instruction granularity
953 record function-call-history prints the execution history at
956 * New native configurations
958 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
959 FreeBSD/powerpc powerpc*-*-freebsd
960 x86_64/Cygwin x86_64-*-cygwin*
961 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
965 ARM AArch64 aarch64*-*-elf
966 ARM AArch64 GNU/Linux aarch64*-*-linux
967 Lynx 178 PowerPC powerpc-*-lynx*178
968 x86_64/Cygwin x86_64-*-cygwin*
969 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
971 * If the configured location of system.gdbinit file (as given by the
972 --with-system-gdbinit option at configure time) is in the
973 data-directory (as specified by --with-gdb-datadir at configure
974 time) or in one of its subdirectories, then GDB will look for the
975 system-wide init file in the directory specified by the
976 --data-directory command-line option.
978 * New command line options:
980 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
981 other initialization files, unlike -nx which disables all of them.
983 * Removed command line options
985 -epoch This was used by the gdb mode in Epoch, an ancient fork of
988 * The 'ptype' and 'whatis' commands now accept an argument to control
991 * 'info proc' now works on some core files.
995 ** Vectors can be created with gdb.Type.vector.
997 ** Python's atexit.register now works in GDB.
999 ** Types can be pretty-printed via a Python API.
1001 ** Python 3 is now supported (in addition to Python 2.4 or later)
1003 ** New class gdb.Architecture exposes GDB's internal representation
1004 of architecture in the Python API.
1006 ** New method Frame.architecture returns the gdb.Architecture object
1007 corresponding to the frame's architecture.
1009 * New Python-based convenience functions:
1011 ** $_memeq(buf1, buf2, length)
1012 ** $_streq(str1, str2)
1014 ** $_regex(str, regex)
1016 * The 'cd' command now defaults to using '~' (the home directory) if not
1019 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1020 default for GCC since November 2000.
1022 * The command 'forward-search' can now be abbreviated as 'fo'.
1024 * The command 'info tracepoints' can now display 'installed on target'
1025 or 'not installed on target' for each non-pending location of tracepoint.
1027 * New configure options
1029 --enable-libmcheck/--disable-libmcheck
1030 By default, development versions are built with -lmcheck on hosts
1031 that support it, in order to help track memory corruption issues.
1032 Release versions, on the other hand, are built without -lmcheck
1033 by default. The --enable-libmcheck/--disable-libmcheck configure
1034 options allow the user to override that default.
1035 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1036 This configure option allows the user to build GDB with
1037 libbabeltrace using which GDB can read Common Trace Format data.
1039 * New commands (for set/show, see "New options" below)
1042 Catch signals. This is similar to "handle", but allows commands and
1043 conditions to be attached.
1046 List the BFDs known to GDB.
1048 python-interactive [command]
1050 Start a Python interactive prompt, or evaluate the optional command
1051 and print the result of expressions.
1054 "py" is a new alias for "python".
1056 enable type-printer [name]...
1057 disable type-printer [name]...
1058 Enable or disable type printers.
1062 ** For the Renesas Super-H architecture, the "regs" command has been removed
1063 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1068 set print type methods (on|off)
1069 show print type methods
1070 Control whether method declarations are displayed by "ptype".
1071 The default is to show them.
1073 set print type typedefs (on|off)
1074 show print type typedefs
1075 Control whether typedef definitions are displayed by "ptype".
1076 The default is to show them.
1078 set filename-display basename|relative|absolute
1079 show filename-display
1080 Control the way in which filenames is displayed.
1081 The default is "relative", which preserves previous behavior.
1083 set trace-buffer-size
1084 show trace-buffer-size
1085 Request target to change the size of trace buffer.
1087 set remote trace-buffer-size-packet auto|on|off
1088 show remote trace-buffer-size-packet
1089 Control the use of the remote protocol `QTBuffer:size' packet.
1093 Control display of debugging messages related to ARM AArch64.
1096 set debug coff-pe-read
1097 show debug coff-pe-read
1098 Control display of debugging messages related to reading of COFF/PE
1103 Control display of debugging messages related to Mach-O symbols
1106 set debug notification
1107 show debug notification
1108 Control display of debugging info for async remote notification.
1112 ** Command parameter changes are now notified using new async record
1113 "=cmd-param-changed".
1114 ** Trace frame changes caused by command "tfind" are now notified using
1115 new async record "=traceframe-changed".
1116 ** The creation, deletion and modification of trace state variables
1117 are now notified using new async records "=tsv-created",
1118 "=tsv-deleted" and "=tsv-modified".
1119 ** The start and stop of process record are now notified using new
1120 async record "=record-started" and "=record-stopped".
1121 ** Memory changes are now notified using new async record
1123 ** The data-disassemble command response will include a "fullname" field
1124 containing the absolute file name when source has been requested.
1125 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1126 command, to allow pattern filling of memory areas.
1127 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1128 library load/unload events.
1129 ** The response to breakpoint commands and breakpoint async records
1130 includes an "installed" field containing a boolean state about each
1131 non-pending tracepoint location is whether installed on target or not.
1132 ** Output of the "-trace-status" command includes a "trace-file" field
1133 containing the name of the trace file being examined. This field is
1134 optional, and only present when examining a trace file.
1135 ** The "fullname" field is now always present along with the "file" field,
1136 even if the file cannot be found by GDB.
1138 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1139 You must have the LZMA library available when configuring GDB for this
1140 feature to be enabled. For more information, see:
1141 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1143 * New remote packets
1146 Set the size of trace buffer. The remote stub reports support for this
1147 packet to gdb's qSupported query.
1150 Enable Branch Trace Store (BTS)-based branch tracing for the current
1151 thread. The remote stub reports support for this packet to gdb's
1155 Disable branch tracing for the current thread. The remote stub reports
1156 support for this packet to gdb's qSupported query.
1159 Read the traced branches for the current thread. The remote stub
1160 reports support for this packet to gdb's qSupported query.
1162 *** Changes in GDB 7.5
1164 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1165 for more x32 ABI info.
1167 * GDB now supports access to MIPS DSP registers on Linux targets.
1169 * GDB now supports debugging microMIPS binaries.
1171 * The "info os" command on GNU/Linux can now display information on
1172 several new classes of objects managed by the operating system:
1173 "info os procgroups" lists process groups
1174 "info os files" lists file descriptors
1175 "info os sockets" lists internet-domain sockets
1176 "info os shm" lists shared-memory regions
1177 "info os semaphores" lists semaphores
1178 "info os msg" lists message queues
1179 "info os modules" lists loaded kernel modules
1181 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1182 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1183 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1184 options and inspect the probe arguments using the new $_probe_arg family
1185 of convenience variables. You can obtain more information about SystemTap
1186 in <http://sourceware.org/systemtap/>.
1188 * GDB now supports reversible debugging on ARM, it allows you to
1189 debug basic ARM and THUMB instructions, and provides
1190 record/replay support.
1192 * The option "symbol-reloading" has been deleted as it is no longer used.
1196 ** GDB commands implemented in Python can now be put in command class
1199 ** The "maint set python print-stack on|off" is now deleted.
1201 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1202 apply "flag enum"-style pretty-printing to any enum.
1204 ** gdb.lookup_symbol can now work when there is no current frame.
1206 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1207 the source at which the symbol was defined.
1209 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1210 method 'value'. The former indicates whether the symbol needs a
1211 frame in order to compute its value, and the latter computes the
1214 ** A new method 'referenced_value' on gdb.Value objects which can
1215 dereference pointer as well as C++ reference values.
1217 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1218 which return the global and static blocks (as gdb.Block objects),
1219 of the underlying symbol table, respectively.
1221 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1222 object associated with a PC value.
1224 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1225 of the address range occupied by code for the current source line.
1227 * Go language support.
1228 GDB now supports debugging programs written in the Go programming
1231 * GDBserver now supports stdio connections.
1232 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1234 * The binary "gdbtui" can no longer be built or installed.
1235 Use "gdb -tui" instead.
1237 * GDB will now print "flag" enums specially. A flag enum is one where
1238 all the enumerator values have no bits in common when pairwise
1239 "and"ed. When printing a value whose type is a flag enum, GDB will
1240 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1241 (gdb) print (enum E) 3
1244 * The filename part of a linespec will now match trailing components
1245 of a source file name. For example, "break gcc/expr.c:1000" will
1246 now set a breakpoint in build/gcc/expr.c, but not
1247 build/libcpp/expr.c.
1249 * The "info proc" and "generate-core-file" commands will now also
1250 work on remote targets connected to GDBserver on Linux.
1252 * The command "info catch" has been removed. It has been disabled
1253 since December 2007.
1255 * The "catch exception" and "catch assert" commands now accept
1256 a condition at the end of the command, much like the "break"
1257 command does. For instance:
1259 (gdb) catch exception Constraint_Error if Barrier = True
1261 Previously, it was possible to add a condition to such catchpoints,
1262 but it had to be done as a second step, after the catchpoint had been
1263 created, using the "condition" command.
1265 * The "info static-tracepoint-marker" command will now also work on
1266 native Linux targets with in-process agent.
1268 * GDB can now set breakpoints on inlined functions.
1270 * The .gdb_index section has been updated to include symbols for
1271 inlined functions. GDB will ignore older .gdb_index sections by
1272 default, which could cause symbol files to be loaded more slowly
1273 until their .gdb_index sections can be recreated. The new command
1274 "set use-deprecated-index-sections on" will cause GDB to use any older
1275 .gdb_index sections it finds. This will restore performance, but the
1276 ability to set breakpoints on inlined functions will be lost in symbol
1277 files with older .gdb_index sections.
1279 The .gdb_index section has also been updated to record more information
1280 about each symbol. This speeds up the "info variables", "info functions"
1281 and "info types" commands when used with programs having the .gdb_index
1282 section, as well as speeding up debugging with shared libraries using
1283 the .gdb_index section.
1285 * Ada support for GDB/MI Variable Objects has been added.
1287 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1292 ** New command -info-os is the MI equivalent of "info os".
1294 ** Output logs ("set logging" and related) now include MI output.
1298 ** "set use-deprecated-index-sections on|off"
1299 "show use-deprecated-index-sections on|off"
1300 Controls the use of deprecated .gdb_index sections.
1302 ** "catch load" and "catch unload" can be used to stop when a shared
1303 library is loaded or unloaded, respectively.
1305 ** "enable count" can be used to auto-disable a breakpoint after
1308 ** "info vtbl" can be used to show the virtual method tables for
1309 C++ and Java objects.
1311 ** "explore" and its sub commands "explore value" and "explore type"
1312 can be used to recursively explore values and types of
1313 expressions. These commands are available only if GDB is
1314 configured with '--with-python'.
1316 ** "info auto-load" shows status of all kinds of auto-loaded files,
1317 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1318 sequences of commands files, "info auto-load python-scripts"
1319 shows status of auto-loading Python script files,
1320 "info auto-load local-gdbinit" shows status of loading init file
1321 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1322 status of inferior specific thread debugging shared library loading.
1324 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1325 and "show auto-load-scripts" commands have been deprecated, use their
1326 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1327 and "show auto-load python-scripts" counterparts instead.
1329 ** "dprintf location,format,args..." creates a dynamic printf, which
1330 is basically a breakpoint that does a printf and immediately
1331 resumes your program's execution, so it is like a printf that you
1332 can insert dynamically at runtime instead of at compiletime.
1334 ** "set print symbol"
1336 Controls whether GDB attempts to display the symbol, if any,
1337 corresponding to addresses it prints. This defaults to "on", but
1338 you can set it to "off" to restore GDB's previous behavior.
1340 * Deprecated commands
1342 ** For the Renesas Super-H architecture, the "regs" command has been
1343 deprecated, and "info all-registers" should be used instead.
1347 Renesas RL78 rl78-*-elf
1348 HP OpenVMS ia64 ia64-hp-openvms*
1350 * GDBserver supports evaluation of breakpoint conditions. When
1351 support is advertised by GDBserver, GDB may be told to send the
1352 breakpoint conditions in bytecode form to GDBserver. GDBserver
1353 will only report the breakpoint trigger to GDB when its condition
1358 set mips compression
1359 show mips compression
1360 Select the compressed ISA encoding used in functions that have no symbol
1361 information available. The encoding can be set to either of:
1364 and is updated automatically from ELF file flags if available.
1366 set breakpoint condition-evaluation
1367 show breakpoint condition-evaluation
1368 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1369 GDBserver ("target"). Default option "auto" chooses the most efficient
1371 This option can improve debugger efficiency depending on the speed of the
1375 Disable auto-loading globally.
1378 Show auto-loading setting of all kinds of auto-loaded files.
1380 set auto-load gdb-scripts on|off
1381 show auto-load gdb-scripts
1382 Control auto-loading of GDB canned sequences of commands files.
1384 set auto-load python-scripts on|off
1385 show auto-load python-scripts
1386 Control auto-loading of Python script files.
1388 set auto-load local-gdbinit on|off
1389 show auto-load local-gdbinit
1390 Control loading of init file (.gdbinit) from current directory.
1392 set auto-load libthread-db on|off
1393 show auto-load libthread-db
1394 Control auto-loading of inferior specific thread debugging shared library.
1396 set auto-load scripts-directory <dir1>[:<dir2>...]
1397 show auto-load scripts-directory
1398 Set a list of directories from which to load auto-loaded scripts.
1399 Automatically loaded Python scripts and GDB scripts are located in one
1400 of the directories listed by this option.
1401 The delimiter (':' above) may differ according to the host platform.
1403 set auto-load safe-path <dir1>[:<dir2>...]
1404 show auto-load safe-path
1405 Set a list of directories from which it is safe to auto-load files.
1406 The delimiter (':' above) may differ according to the host platform.
1408 set debug auto-load on|off
1409 show debug auto-load
1410 Control display of debugging info for auto-loading the files above.
1412 set dprintf-style gdb|call|agent
1414 Control the way in which a dynamic printf is performed; "gdb"
1415 requests a GDB printf command, while "call" causes dprintf to call a
1416 function in the inferior. "agent" requests that the target agent
1417 (such as GDBserver) do the printing.
1419 set dprintf-function <expr>
1420 show dprintf-function
1421 set dprintf-channel <expr>
1422 show dprintf-channel
1423 Set the function and optional first argument to the call when using
1424 the "call" style of dynamic printf.
1426 set disconnected-dprintf on|off
1427 show disconnected-dprintf
1428 Control whether agent-style dynamic printfs continue to be in effect
1429 after GDB disconnects.
1431 * New configure options
1433 --with-auto-load-dir
1434 Configure default value for the 'set auto-load scripts-directory'
1435 setting above. It defaults to '$debugdir:$datadir/auto-load',
1436 $debugdir representing global debugging info directories (available
1437 via 'show debug-file-directory') and $datadir representing GDB's data
1438 directory (available via 'show data-directory').
1440 --with-auto-load-safe-path
1441 Configure default value for the 'set auto-load safe-path' setting
1442 above. It defaults to the --with-auto-load-dir setting.
1444 --without-auto-load-safe-path
1445 Set 'set auto-load safe-path' to '/', effectively disabling this
1448 * New remote packets
1450 z0/z1 conditional breakpoints extension
1452 The z0/z1 breakpoint insertion packets have been extended to carry
1453 a list of conditional expressions over to the remote stub depending on the
1454 condition evaluation mode. The use of this extension can be controlled
1455 via the "set remote conditional-breakpoints-packet" command.
1459 Specify the signals which the remote stub may pass to the debugged
1460 program without GDB involvement.
1462 * New command line options
1464 --init-command=FILE, -ix Like --command, -x but execute it
1465 before loading inferior.
1466 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1467 execute it before loading inferior.
1469 *** Changes in GDB 7.4
1471 * GDB now handles ambiguous linespecs more consistently; the existing
1472 FILE:LINE support has been expanded to other types of linespecs. A
1473 breakpoint will now be set on all matching locations in all
1474 inferiors, and locations will be added or removed according to
1477 * GDB now allows you to skip uninteresting functions and files when
1478 stepping with the "skip function" and "skip file" commands.
1480 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1481 and "show remote hardware-watchpoint-length-limit". These allows to
1482 set or show the maximum length limit (in bytes) of a remote
1483 target hardware watchpoint.
1485 This allows e.g. to use "unlimited" hardware watchpoints with the
1486 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1487 watchpoints are slower than real hardware watchpoints but are
1488 significantly faster than gdb software watchpoints.
1492 ** The register_pretty_printer function in module gdb.printing now takes
1493 an optional `replace' argument. If True, the new printer replaces any
1496 ** The "maint set python print-stack on|off" command has been
1497 deprecated and will be deleted in GDB 7.5.
1498 A new command: "set python print-stack none|full|message" has
1499 replaced it. Additionally, the default for "print-stack" is
1500 now "message", which just prints the error message without
1503 ** A prompt substitution hook (prompt_hook) is now available to the
1506 ** A new Python module, gdb.prompt has been added to the GDB Python
1507 modules library. This module provides functionality for
1508 escape sequences in prompts (used by set/show
1509 extended-prompt). These escape sequences are replaced by their
1510 corresponding value.
1512 ** Python commands and convenience-functions located in
1513 'data-directory'/python/gdb/command and
1514 'data-directory'/python/gdb/function are now automatically loaded
1517 ** Blocks now provide four new attributes. global_block and
1518 static_block will return the global and static blocks
1519 respectively. is_static and is_global are boolean attributes
1520 that indicate if the block is one of those two types.
1522 ** Symbols now provide the "type" attribute, the type of the symbol.
1524 ** The "gdb.breakpoint" function has been deprecated in favor of
1527 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1528 of a function. This class is based on the "finish" command
1529 available in the CLI.
1531 ** Type objects for struct and union types now allow access to
1532 the fields using standard Python dictionary (mapping) methods.
1533 For example, "some_type['myfield']" now works, as does
1534 "some_type.items()".
1536 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1539 ** A new function, "deep_items" has been added to the gdb.types
1540 module in the GDB Python modules library. This function returns
1541 an iterator over the fields of a struct or union type. Unlike
1542 the standard Python "iteritems" method, it will recursively traverse
1543 any anonymous fields.
1547 ** "*stopped" events can report several new "reason"s, such as
1550 ** Breakpoint changes are now notified using new async records, like
1551 "=breakpoint-modified".
1553 ** New command -ada-task-info.
1555 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1556 $sdir specifies the default system locations of shared libraries.
1557 $pdir specifies the directory where the libpthread used by the application
1560 GDB no longer looks in $sdir and $pdir after it has searched the directories
1561 mentioned in libthread-db-search-path. If you want to search those
1562 directories, they must be specified in libthread-db-search-path.
1563 The default value of libthread-db-search-path on GNU/Linux and Solaris
1564 systems is now "$sdir:$pdir".
1566 $pdir is not supported by gdbserver, it is currently ignored.
1567 $sdir is supported by gdbserver.
1569 * New configure option --with-iconv-bin.
1570 When using the internationalization support like the one in the GNU C
1571 library, GDB will invoke the "iconv" program to get a list of supported
1572 character sets. If this program lives in a non-standard location, one can
1573 use this option to specify where to find it.
1575 * When natively debugging programs on PowerPC BookE processors running
1576 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1577 watchpoints, which specify a mask in addition to an address to watch.
1578 The mask specifies that some bits of an address (the bits which are
1579 reset in the mask) should be ignored when matching the address accessed
1580 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1581 section in the user manual for more details.
1583 * The new option --once causes GDBserver to stop listening for connections once
1584 the first connection is made. The listening port used by GDBserver will
1585 become available after that.
1587 * New commands "info macros" and "alias" have been added.
1589 * New function parameters suffix @entry specifies value of function parameter
1590 at the time the function got called. Entry values are available only since
1596 "!" is now an alias of the "shell" command.
1597 Note that no space is needed between "!" and SHELL COMMAND.
1601 watch EXPRESSION mask MASK_VALUE
1602 The watch command now supports the mask argument which allows creation
1603 of masked watchpoints, if the current architecture supports this feature.
1605 info auto-load-scripts [REGEXP]
1606 This command was formerly named "maintenance print section-scripts".
1607 It is now generally useful and is no longer a maintenance-only command.
1609 info macro [-all] [--] MACRO
1610 The info macro command has new options `-all' and `--'. The first for
1611 printing all definitions of a macro. The second for explicitly specifying
1612 the end of arguments and the beginning of the macro name in case the macro
1613 name starts with a hyphen.
1615 collect[/s] EXPRESSIONS
1616 The tracepoint collect command now takes an optional modifier "/s"
1617 that directs it to dereference pointer-to-character types and
1618 collect the bytes of memory up to a zero byte. The behavior is
1619 similar to what you see when you use the regular print command on a
1620 string. An optional integer following the "/s" sets a bound on the
1621 number of bytes that will be collected.
1624 The trace start command now interprets any supplied arguments as a
1625 note to be recorded with the trace run, with an effect similar to
1626 setting the variable trace-notes.
1629 The trace stop command now interprets any arguments as a note to be
1630 mentioned along with the tstatus report that the trace was stopped
1631 with a command. The effect is similar to setting the variable
1634 * Tracepoints can now be enabled and disabled at any time after a trace
1635 experiment has been started using the standard "enable" and "disable"
1636 commands. It is now possible to start a trace experiment with no enabled
1637 tracepoints; GDB will display a warning, but will allow the experiment to
1638 begin, assuming that tracepoints will be enabled as needed while the trace
1641 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1642 locations with 4-byte instructions, when they were previously
1643 limited to locations with instructions of 5 bytes or longer.
1647 set debug dwarf2-read
1648 show debug dwarf2-read
1649 Turns on or off display of debugging messages related to reading
1650 DWARF debug info. The default is off.
1652 set debug symtab-create
1653 show debug symtab-create
1654 Turns on or off display of debugging messages related to symbol table
1655 creation. The default is off.
1658 show extended-prompt
1659 Set the GDB prompt, and allow escape sequences to be inserted to
1660 display miscellaneous information (see 'help set extended-prompt'
1661 for the list of sequences). This prompt (and any information
1662 accessed through the escape sequences) is updated every time the
1663 prompt is displayed.
1665 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1666 show print entry-values
1667 Set printing of frame argument values at function entry. In some cases
1668 GDB can determine the value of function argument which was passed by the
1669 function caller, even if the value was modified inside the called function.
1671 set debug entry-values
1672 show debug entry-values
1673 Control display of debugging info for determining frame argument values at
1674 function entry and virtual tail call frames.
1676 set basenames-may-differ
1677 show basenames-may-differ
1678 Set whether a source file may have multiple base names.
1679 (A "base name" is the name of a file with the directory part removed.
1680 Example: The base name of "/home/user/hello.c" is "hello.c".)
1681 If set, GDB will canonicalize file names (e.g., expand symlinks)
1682 before comparing them. Canonicalization is an expensive operation,
1683 but it allows the same file be known by more than one base name.
1684 If not set (the default), all source files are assumed to have just
1685 one base name, and gdb will do file name comparisons more efficiently.
1691 Set a user name and notes for the current and any future trace runs.
1692 This is useful for long-running and/or disconnected traces, to
1693 inform others (or yourself) as to who is running the trace, supply
1694 contact information, or otherwise explain what is going on.
1696 set trace-stop-notes
1697 show trace-stop-notes
1698 Set a note attached to the trace run, that is displayed when the
1699 trace has been stopped by a tstop command. This is useful for
1700 instance as an explanation, if you are stopping a trace run that was
1701 started by someone else.
1703 * New remote packets
1707 Dynamically enable a tracepoint in a started trace experiment.
1711 Dynamically disable a tracepoint in a started trace experiment.
1715 Set the user and notes of the trace run.
1719 Query the current status of a tracepoint.
1723 Query the minimum length of instruction at which a fast tracepoint may
1726 * Dcache size (number of lines) and line-size are now runtime-configurable
1727 via "set dcache line" and "set dcache line-size" commands.
1731 Texas Instruments TMS320C6x tic6x-*-*
1735 Renesas RL78 rl78-*-elf
1737 *** Changes in GDB 7.3.1
1739 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1741 *** Changes in GDB 7.3
1743 * GDB has a new command: "thread find [REGEXP]".
1744 It finds the thread id whose name, target id, or thread extra info
1745 matches the given regular expression.
1747 * The "catch syscall" command now works on mips*-linux* targets.
1749 * The -data-disassemble MI command now supports modes 2 and 3 for
1750 dumping the instruction opcodes.
1752 * New command line options
1754 -data-directory DIR Specify DIR as the "data-directory".
1755 This is mostly for testing purposes.
1757 * The "maint set python auto-load on|off" command has been renamed to
1758 "set auto-load-scripts on|off".
1760 * GDB has a new command: "set directories".
1761 It is like the "dir" command except that it replaces the
1762 source path list instead of augmenting it.
1764 * GDB now understands thread names.
1766 On GNU/Linux, "info threads" will display the thread name as set by
1767 prctl or pthread_setname_np.
1769 There is also a new command, "thread name", which can be used to
1770 assign a name internally for GDB to display.
1773 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1774 has been integrated into GDB.
1778 ** The function gdb.Write now accepts an optional keyword 'stream'.
1779 This keyword, when provided, will direct the output to either
1780 stdout, stderr, or GDB's logging output.
1782 ** Parameters can now be be sub-classed in Python, and in particular
1783 you may implement the get_set_doc and get_show_doc functions.
1784 This improves how Parameter set/show documentation is processed
1785 and allows for more dynamic content.
1787 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1788 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1789 have an is_valid method.
1791 ** Breakpoints can now be sub-classed in Python, and in particular
1792 you may implement a 'stop' function that is executed each time
1793 the inferior reaches that breakpoint.
1795 ** New function gdb.lookup_global_symbol looks up a global symbol.
1797 ** GDB values in Python are now callable if the value represents a
1798 function. For example, if 'some_value' represents a function that
1799 takes two integer parameters and returns a value, you can call
1800 that function like so:
1802 result = some_value (10,20)
1804 ** Module gdb.types has been added.
1805 It contains a collection of utilities for working with gdb.Types objects:
1806 get_basic_type, has_field, make_enum_dict.
1808 ** Module gdb.printing has been added.
1809 It contains utilities for writing and registering pretty-printers.
1810 New classes: PrettyPrinter, SubPrettyPrinter,
1811 RegexpCollectionPrettyPrinter.
1812 New function: register_pretty_printer.
1814 ** New commands "info pretty-printers", "enable pretty-printer" and
1815 "disable pretty-printer" have been added.
1817 ** gdb.parameter("directories") is now available.
1819 ** New function gdb.newest_frame returns the newest frame in the
1822 ** The gdb.InferiorThread class has a new "name" attribute. This
1823 holds the thread's name.
1825 ** Python Support for Inferior events.
1826 Python scripts can add observers to be notified of events
1827 occurring in the process being debugged.
1828 The following events are currently supported:
1829 - gdb.events.cont Continue event.
1830 - gdb.events.exited Inferior exited event.
1831 - gdb.events.stop Signal received, and Breakpoint hit events.
1835 ** GDB now puts template parameters in scope when debugging in an
1836 instantiation. For example, if you have:
1838 template<int X> int func (void) { return X; }
1840 then if you step into func<5>, "print X" will show "5". This
1841 feature requires proper debuginfo support from the compiler; it
1842 was added to GCC 4.5.
1844 ** The motion commands "next", "finish", "until", and "advance" now
1845 work better when exceptions are thrown. In particular, GDB will
1846 no longer lose control of the inferior; instead, the GDB will
1847 stop the inferior at the point at which the exception is caught.
1848 This functionality requires a change in the exception handling
1849 code that was introduced in GCC 4.5.
1851 * GDB now follows GCC's rules on accessing volatile objects when
1852 reading or writing target state during expression evaluation.
1853 One notable difference to prior behavior is that "print x = 0"
1854 no longer generates a read of x; the value of the assignment is
1855 now always taken directly from the value being assigned.
1857 * GDB now has some support for using labels in the program's source in
1858 linespecs. For instance, you can use "advance label" to continue
1859 execution to a label.
1861 * GDB now has support for reading and writing a new .gdb_index
1862 section. This section holds a fast index of DWARF debugging
1863 information and can be used to greatly speed up GDB startup and
1864 operation. See the documentation for `save gdb-index' for details.
1866 * The "watch" command now accepts an optional "-location" argument.
1867 When used, this causes GDB to watch the memory referred to by the
1868 expression. Such a watchpoint is never deleted due to it going out
1871 * GDB now supports thread debugging of core dumps on GNU/Linux.
1873 GDB now activates thread debugging using the libthread_db library
1874 when debugging GNU/Linux core dumps, similarly to when debugging
1875 live processes. As a result, when debugging a core dump file, GDB
1876 is now able to display pthread_t ids of threads. For example, "info
1877 threads" shows the same output as when debugging the process when it
1878 was live. In earlier releases, you'd see something like this:
1881 * 1 LWP 6780 main () at main.c:10
1883 While now you see this:
1886 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1888 It is also now possible to inspect TLS variables when debugging core
1891 When debugging a core dump generated on a machine other than the one
1892 used to run GDB, you may need to point GDB at the correct
1893 libthread_db library with the "set libthread-db-search-path"
1894 command. See the user manual for more details on this command.
1896 * When natively debugging programs on PowerPC BookE processors running
1897 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1898 which stop execution of the inferior whenever it executes an instruction
1899 at any address within the specified range. See the "PowerPC Embedded"
1900 section in the user manual for more details.
1902 * New features in the GDB remote stub, GDBserver
1904 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1905 and i686 LynxOS (version 5.x).
1907 ** GDBserver is now supported on Blackfin Linux.
1909 * New native configurations
1911 ia64 HP-UX ia64-*-hpux*
1915 Analog Devices, Inc. Blackfin Processor bfin-*
1917 * Ada task switching is now supported on sparc-elf targets when
1918 debugging a program using the Ravenscar Profile. For more information,
1919 see the "Tasking Support when using the Ravenscar Profile" section
1920 in the GDB user manual.
1922 * Guile support was removed.
1924 * New features in the GNU simulator
1926 ** The --map-info flag lists all known core mappings.
1928 ** CFI flashes may be simulated via the "cfi" device.
1930 *** Changes in GDB 7.2
1932 * Shared library support for remote targets by default
1934 When GDB is configured for a generic, non-OS specific target, like
1935 for example, --target=arm-eabi or one of the many *-*-elf targets,
1936 GDB now queries remote stubs for loaded shared libraries using the
1937 `qXfer:libraries:read' packet. Previously, shared library support
1938 was always disabled for such configurations.
1942 ** Argument Dependent Lookup (ADL)
1944 In C++ ADL lookup directs function search to the namespaces of its
1945 arguments even if the namespace has not been imported.
1955 Here the compiler will search for `foo' in the namespace of 'b'
1956 and find A::foo. GDB now supports this. This construct is commonly
1957 used in the Standard Template Library for operators.
1959 ** Improved User Defined Operator Support
1961 In addition to member operators, GDB now supports lookup of operators
1962 defined in a namespace and imported with a `using' directive, operators
1963 defined in the global scope, operators imported implicitly from an
1964 anonymous namespace, and the ADL operators mentioned in the previous
1966 GDB now also supports proper overload resolution for all the previously
1967 mentioned flavors of operators.
1969 ** static const class members
1971 Printing of static const class members that are initialized in the
1972 class definition has been fixed.
1974 * Windows Thread Information Block access.
1976 On Windows targets, GDB now supports displaying the Windows Thread
1977 Information Block (TIB) structure. This structure is visible either
1978 by using the new command `info w32 thread-information-block' or, by
1979 dereferencing the new convenience variable named `$_tlb', a
1980 thread-specific pointer to the TIB. This feature is also supported
1981 when remote debugging using GDBserver.
1983 * Static tracepoints
1985 Static tracepoints are calls in the user program into a tracing
1986 library. One such library is a port of the LTTng kernel tracer to
1987 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1988 When debugging with GDBserver, GDB now supports combining the GDB
1989 tracepoint machinery with such libraries. For example: the user can
1990 use GDB to probe a static tracepoint marker (a call from the user
1991 program into the tracing library) with the new "strace" command (see
1992 "New commands" below). This creates a "static tracepoint" in the
1993 breakpoint list, that can be manipulated with the same feature set
1994 as fast and regular tracepoints. E.g., collect registers, local and
1995 global variables, collect trace state variables, and define
1996 tracepoint conditions. In addition, the user can collect extra
1997 static tracepoint marker specific data, by collecting the new
1998 $_sdata internal variable. When analyzing the trace buffer, you can
1999 inspect $_sdata like any other variable available to GDB. For more
2000 information, see the "Tracepoints" chapter in GDB user manual. New
2001 remote packets have been defined to support static tracepoints, see
2002 the "New remote packets" section below.
2004 * Better reconstruction of tracepoints after disconnected tracing
2006 GDB will attempt to download the original source form of tracepoint
2007 definitions when starting a trace run, and then will upload these
2008 upon reconnection to the target, resulting in a more accurate
2009 reconstruction of the tracepoints that are in use on the target.
2013 You can now exercise direct control over the ways that GDB can
2014 affect your program. For instance, you can disallow the setting of
2015 breakpoints, so that the program can run continuously (assuming
2016 non-stop mode). In addition, the "observer" variable is available
2017 to switch all of the different controls; in observer mode, GDB
2018 cannot affect the target's behavior at all, which is useful for
2019 tasks like diagnosing live systems in the field.
2021 * The new convenience variable $_thread holds the number of the
2024 * New remote packets
2028 Return the address of the Windows Thread Information Block of a given thread.
2032 In response to several of the tracepoint packets, the target may now
2033 also respond with a number of intermediate `qRelocInsn' request
2034 packets before the final result packet, to have GDB handle
2035 relocating an instruction to execute at a different address. This
2036 is particularly useful for stubs that support fast tracepoints. GDB
2037 reports support for this feature in the qSupported packet.
2041 List static tracepoint markers in the target program.
2045 List static tracepoint markers at a given address in the target
2048 qXfer:statictrace:read
2050 Read the static trace data collected (by a `collect $_sdata'
2051 tracepoint action). The remote stub reports support for this packet
2052 to gdb's qSupported query.
2056 Send the current settings of GDB's permission flags.
2060 Send part of the source (textual) form of a tracepoint definition,
2061 which includes location, conditional, and action list.
2063 * The source command now accepts a -s option to force searching for the
2064 script in the source search path even if the script name specifies
2067 * New features in the GDB remote stub, GDBserver
2069 - GDBserver now support tracepoints (including fast tracepoints, and
2070 static tracepoints). The feature is currently supported by the
2071 i386-linux and amd64-linux builds. See the "Tracepoints support
2072 in gdbserver" section in the manual for more information.
2074 GDBserver JIT compiles the tracepoint's conditional agent
2075 expression bytecode into native code whenever possible for low
2076 overhead dynamic tracepoints conditionals. For such tracepoints,
2077 an expression that examines program state is evaluated when the
2078 tracepoint is reached, in order to determine whether to capture
2079 trace data. If the condition is simple and false, processing the
2080 tracepoint finishes very quickly and no data is gathered.
2082 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2083 for static tracepoints support.
2085 - GDBserver now supports x86_64 Windows 64-bit debugging.
2087 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2088 it understands register description.
2090 * The --batch flag now disables pagination and queries.
2092 * X86 general purpose registers
2094 GDB now supports reading/writing byte, word and double-word x86
2095 general purpose registers directly. This means you can use, say,
2096 $ah or $ax to refer, respectively, to the byte register AH and
2097 16-bit word register AX that are actually portions of the 32-bit
2098 register EAX or 64-bit register RAX.
2100 * The `commands' command now accepts a range of breakpoints to modify.
2101 A plain `commands' following a command that creates multiple
2102 breakpoints affects all the breakpoints set by that command. This
2103 applies to breakpoints set by `rbreak', and also applies when a
2104 single `break' command creates multiple breakpoints (e.g.,
2105 breakpoints on overloaded c++ functions).
2107 * The `rbreak' command now accepts a filename specification as part of
2108 its argument, limiting the functions selected by the regex to those
2109 in the specified file.
2111 * Support for remote debugging Windows and SymbianOS shared libraries
2112 from Unix hosts has been improved. Non Windows GDB builds now can
2113 understand target reported file names that follow MS-DOS based file
2114 system semantics, such as file names that include drive letters and
2115 use the backslash character as directory separator. This makes it
2116 possible to transparently use the "set sysroot" and "set
2117 solib-search-path" on Unix hosts to point as host copies of the
2118 target's shared libraries. See the new command "set
2119 target-file-system-kind" described below, and the "Commands to
2120 specify files" section in the user manual for more information.
2124 eval template, expressions...
2125 Convert the values of one or more expressions under the control
2126 of the string template to a command line, and call it.
2128 set target-file-system-kind unix|dos-based|auto
2129 show target-file-system-kind
2130 Set or show the assumed file system kind for target reported file
2133 save breakpoints <filename>
2134 Save all current breakpoint definitions to a file suitable for use
2135 in a later debugging session. To read the saved breakpoint
2136 definitions, use the `source' command.
2138 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2141 info static-tracepoint-markers
2142 Display information about static tracepoint markers in the target.
2144 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2145 Define a static tracepoint by probing a marker at the given
2146 function, line, address, or marker ID.
2150 Enable and disable observer mode.
2152 set may-write-registers on|off
2153 set may-write-memory on|off
2154 set may-insert-breakpoints on|off
2155 set may-insert-tracepoints on|off
2156 set may-insert-fast-tracepoints on|off
2157 set may-interrupt on|off
2158 Set individual permissions for GDB effects on the target. Note that
2159 some of these settings can have undesirable or surprising
2160 consequences, particularly when changed in the middle of a session.
2161 For instance, disabling the writing of memory can prevent
2162 breakpoints from being inserted, cause single-stepping to fail, or
2163 even crash your program, if you disable after breakpoints have been
2164 inserted. However, GDB should not crash.
2166 set record memory-query on|off
2167 show record memory-query
2168 Control whether to stop the inferior if memory changes caused
2169 by an instruction cannot be recorded.
2174 The disassemble command now supports "start,+length" form of two arguments.
2178 ** GDB now provides a new directory location, called the python directory,
2179 where Python scripts written for GDB can be installed. The location
2180 of that directory is <data-directory>/python, where <data-directory>
2181 is the GDB data directory. For more details, see section `Scripting
2182 GDB using Python' in the manual.
2184 ** The GDB Python API now has access to breakpoints, symbols, symbol
2185 tables, program spaces, inferiors, threads and frame's code blocks.
2186 Additionally, GDB Parameters can now be created from the API, and
2187 manipulated via set/show in the CLI.
2189 ** New functions gdb.target_charset, gdb.target_wide_charset,
2190 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2192 ** New exception gdb.GdbError.
2194 ** Pretty-printers are now also looked up in the current program space.
2196 ** Pretty-printers can now be individually enabled and disabled.
2198 ** GDB now looks for names of Python scripts to auto-load in a
2199 special section named `.debug_gdb_scripts', in addition to looking
2200 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2202 * Tracepoint actions were unified with breakpoint commands. In particular,
2203 there are no longer differences in "info break" output for breakpoints and
2204 tracepoints and the "commands" command can be used for both tracepoints and
2205 regular breakpoints.
2209 ARM Symbian arm*-*-symbianelf*
2211 * D language support.
2212 GDB now supports debugging programs written in the D programming
2215 * GDB now supports the extended ptrace interface for PowerPC which is
2216 available since Linux kernel version 2.6.34. This automatically enables
2217 any hardware breakpoints and additional hardware watchpoints available in
2218 the processor. The old ptrace interface exposes just one hardware
2219 watchpoint and no hardware breakpoints.
2221 * GDB is now able to use the Data Value Compare (DVC) register available on
2222 embedded PowerPC processors to implement in hardware simple watchpoint
2223 conditions of the form:
2225 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2227 This works in native GDB running on Linux kernels with the extended ptrace
2228 interface mentioned above.
2230 *** Changes in GDB 7.1
2234 ** Namespace Support
2236 GDB now supports importing of namespaces in C++. This enables the
2237 user to inspect variables from imported namespaces. Support for
2238 namepace aliasing has also been added. So, if a namespace is
2239 aliased in the current scope (e.g. namepace C=A; ) the user can
2240 print variables using the alias (e.g. (gdb) print C::x).
2244 All known bugs relating to the printing of virtual base class were
2245 fixed. It is now possible to call overloaded static methods using a
2250 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2251 and reinterpret_cast<> are now handled by the C++ expression parser.
2255 Xilinx MicroBlaze microblaze-*-*
2260 Xilinx MicroBlaze microblaze
2263 * Multi-program debugging.
2265 GDB now has support for multi-program (a.k.a. multi-executable or
2266 multi-exec) debugging. This allows for debugging multiple inferiors
2267 simultaneously each running a different program under the same GDB
2268 session. See "Debugging Multiple Inferiors and Programs" in the
2269 manual for more information. This implied some user visible changes
2270 in the multi-inferior support. For example, "info inferiors" now
2271 lists inferiors that are not running yet or that have exited
2272 already. See also "New commands" and "New options" below.
2274 * New tracing features
2276 GDB's tracepoint facility now includes several new features:
2278 ** Trace state variables
2280 GDB tracepoints now include support for trace state variables, which
2281 are variables managed by the target agent during a tracing
2282 experiment. They are useful for tracepoints that trigger each
2283 other, so for instance one tracepoint can count hits in a variable,
2284 and then a second tracepoint has a condition that is true when the
2285 count reaches a particular value. Trace state variables share the
2286 $-syntax of GDB convenience variables, and can appear in both
2287 tracepoint actions and condition expressions. Use the "tvariable"
2288 command to create, and "info tvariables" to view; see "Trace State
2289 Variables" in the manual for more detail.
2293 GDB now includes an option for defining fast tracepoints, which
2294 targets may implement more efficiently, such as by installing a jump
2295 into the target agent rather than a trap instruction. The resulting
2296 speedup can be by two orders of magnitude or more, although the
2297 tradeoff is that some program locations on some target architectures
2298 might not allow fast tracepoint installation, for instance if the
2299 instruction to be replaced is shorter than the jump. To request a
2300 fast tracepoint, use the "ftrace" command, with syntax identical to
2301 the regular trace command.
2303 ** Disconnected tracing
2305 It is now possible to detach GDB from the target while it is running
2306 a trace experiment, then reconnect later to see how the experiment
2307 is going. In addition, a new variable disconnected-tracing lets you
2308 tell the target agent whether to continue running a trace if the
2309 connection is lost unexpectedly.
2313 GDB now has the ability to save the trace buffer into a file, and
2314 then use that file as a target, similarly to you can do with
2315 corefiles. You can select trace frames, print data that was
2316 collected in them, and use tstatus to display the state of the
2317 tracing run at the moment that it was saved. To create a trace
2318 file, use "tsave <filename>", and to use it, do "target tfile
2321 ** Circular trace buffer
2323 You can ask the target agent to handle the trace buffer as a
2324 circular buffer, discarding the oldest trace frames to make room for
2325 newer ones, by setting circular-trace-buffer to on. This feature may
2326 not be available for all target agents.
2331 The disassemble command, when invoked with two arguments, now requires
2332 the arguments to be comma-separated.
2335 The info variables command now displays variable definitions. Files
2336 which only declare a variable are not shown.
2339 The source command is now capable of sourcing Python scripts.
2340 This feature is dependent on the debugger being build with Python
2343 Related to this enhancement is also the introduction of a new command
2344 "set script-extension" (see below).
2346 * New commands (for set/show, see "New options" below)
2348 record save [<FILENAME>]
2349 Save a file (in core file format) containing the process record
2350 execution log for replay debugging at a later time.
2352 record restore <FILENAME>
2353 Restore the process record execution log that was saved at an
2354 earlier time, for replay debugging.
2356 add-inferior [-copies <N>] [-exec <FILENAME>]
2359 clone-inferior [-copies <N>] [ID]
2360 Make a new inferior ready to execute the same program another
2361 inferior has loaded.
2366 maint info program-spaces
2367 List the program spaces loaded into GDB.
2369 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2370 show remote interrupt-sequence
2371 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2372 as the sequence to the remote target in order to interrupt the execution.
2373 Ctrl-C is a default. Some system prefers BREAK which is high level of
2374 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2375 Magic SysRq g. It is BREAK signal and character 'g'.
2377 set remote interrupt-on-connect [on | off]
2378 show remote interrupt-on-connect
2379 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2380 remote target when gdb connects to it. This is needed when you debug
2383 set remotebreak [on | off]
2385 Deprecated. Use "set/show remote interrupt-sequence" instead.
2387 tvariable $NAME [ = EXP ]
2388 Create or modify a trace state variable.
2391 List trace state variables and their values.
2393 delete tvariable $NAME ...
2394 Delete one or more trace state variables.
2397 Evaluate the given expressions without collecting anything into the
2398 trace buffer. (Valid in tracepoint actions only.)
2400 ftrace FN / FILE:LINE / *ADDR
2401 Define a fast tracepoint at the given function, line, or address.
2403 * New expression syntax
2405 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2406 GDB now parses 0b101010 identically with 42.
2410 set follow-exec-mode new|same
2411 show follow-exec-mode
2412 Control whether GDB reuses the same inferior across an exec call or
2413 creates a new one. This is useful to be able to restart the old
2414 executable after the inferior having done an exec call.
2416 set default-collect EXPR, ...
2417 show default-collect
2418 Define a list of expressions to be collected at each tracepoint.
2419 This is a useful way to ensure essential items are not overlooked,
2420 such as registers or a critical global variable.
2422 set disconnected-tracing
2423 show disconnected-tracing
2424 If set to 1, the target is instructed to continue tracing if it
2425 loses its connection to GDB. If 0, the target is to stop tracing
2428 set circular-trace-buffer
2429 show circular-trace-buffer
2430 If set to on, the target is instructed to use a circular trace buffer
2431 and discard the oldest trace frames instead of stopping the trace due
2432 to a full trace buffer. If set to off, the trace stops when the buffer
2433 fills up. Some targets may not support this.
2435 set script-extension off|soft|strict
2436 show script-extension
2437 If set to "off", the debugger does not perform any script language
2438 recognition, and all sourced files are assumed to be GDB scripts.
2439 If set to "soft" (the default), files are sourced according to
2440 filename extension, falling back to GDB scripts if the first
2442 If set to "strict", files are sourced according to filename extension.
2444 set ada trust-PAD-over-XVS on|off
2445 show ada trust-PAD-over-XVS
2446 If off, activate a workaround against a bug in the debugging information
2447 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2448 the GCC sources for more information about the GNAT encoding and
2449 PAD types in particular). It is always safe to set this option to
2450 off, but this introduces a slight performance penalty. The default
2453 * Python API Improvements
2455 ** GDB provides the new class gdb.LazyString. This is useful in
2456 some pretty-printing cases. The new method gdb.Value.lazy_string
2457 provides a simple way to create objects of this type.
2459 ** The fields returned by gdb.Type.fields now have an
2460 `is_base_class' attribute.
2462 ** The new method gdb.Type.range returns the range of an array type.
2464 ** The new method gdb.parse_and_eval can be used to parse and
2465 evaluate an expression.
2467 * New remote packets
2470 Define a trace state variable.
2473 Get the current value of a trace state variable.
2476 Set desired tracing behavior upon disconnection.
2479 Set the trace buffer to be linear or circular.
2482 Get data about the tracepoints currently in use.
2486 Process record now works correctly with hardware watchpoints.
2488 Multiple bug fixes have been made to the mips-irix port, making it
2489 much more reliable. In particular:
2490 - Debugging threaded applications is now possible again. Previously,
2491 GDB would hang while starting the program, or while waiting for
2492 the program to stop at a breakpoint.
2493 - Attaching to a running process no longer hangs.
2494 - An error occurring while loading a core file has been fixed.
2495 - Changing the value of the PC register now works again. This fixes
2496 problems observed when using the "jump" command, or when calling
2497 a function from GDB, or even when assigning a new value to $pc.
2498 - With the "finish" and "return" commands, the return value for functions
2499 returning a small array is now correctly printed.
2500 - It is now possible to break on shared library code which gets executed
2501 during a shared library init phase (code executed while executing
2502 their .init section). Previously, the breakpoint would have no effect.
2503 - GDB is now able to backtrace through the signal handler for
2504 non-threaded programs.
2506 PIE (Position Independent Executable) programs debugging is now supported.
2507 This includes debugging execution of PIC (Position Independent Code) shared
2508 libraries although for that, it should be possible to run such libraries as an
2511 *** Changes in GDB 7.0
2513 * GDB now has an interface for JIT compilation. Applications that
2514 dynamically generate code can create symbol files in memory and register
2515 them with GDB. For users, the feature should work transparently, and
2516 for JIT developers, the interface is documented in the GDB manual in the
2517 "JIT Compilation Interface" chapter.
2519 * Tracepoints may now be conditional. The syntax is as for
2520 breakpoints; either an "if" clause appended to the "trace" command,
2521 or the "condition" command is available. GDB sends the condition to
2522 the target for evaluation using the same bytecode format as is used
2523 for tracepoint actions.
2525 * The disassemble command now supports: an optional /r modifier, print the
2526 raw instructions in hex as well as in symbolic form, and an optional /m
2527 modifier to print mixed source+assembly.
2529 * Process record and replay
2531 In a architecture environment that supports ``process record and
2532 replay'', ``process record and replay'' target can record a log of
2533 the process execution, and replay it with both forward and reverse
2536 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2537 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2538 set execution-direction {forward|reverse}, for targets that support
2541 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2542 feature is available with a native GDB running on kernel version
2545 * GDB now has support for multi-byte and wide character sets on the
2546 target. Strings whose character type is wchar_t, char16_t, or
2547 char32_t are now correctly printed. GDB supports wide- and unicode-
2548 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2549 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2550 `printf'. This feature requires iconv to work properly; if your
2551 system does not have a working iconv, GDB can use GNU libiconv. See
2552 the installation instructions for more information.
2554 * GDB now supports automatic retrieval of shared library files from
2555 remote targets. To use this feature, specify a system root that begins
2556 with the `remote:' prefix, either via the `set sysroot' command or via
2557 the `--with-sysroot' configure-time option.
2559 * "info sharedlibrary" now takes an optional regex of libraries to show,
2560 and it now reports if a shared library has no debugging information.
2562 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2563 now complete on file names.
2565 * When completing in expressions, gdb will attempt to limit
2566 completions to allowable structure or union fields, where appropriate.
2567 For instance, consider:
2569 # struct example { int f1; double f2; };
2570 # struct example variable;
2573 If the user types TAB at the end of this command line, the available
2574 completions will be "f1" and "f2".
2576 * Inlined functions are now supported. They show up in backtraces, and
2577 the "step", "next", and "finish" commands handle them automatically.
2579 * GDB now supports the token-splicing (##) and stringification (#)
2580 operators when expanding macros. It also supports variable-arity
2583 * GDB now supports inspecting extra signal information, exported by
2584 the new $_siginfo convenience variable. The feature is currently
2585 implemented on linux ARM, i386 and amd64.
2587 * GDB can now display the VFP floating point registers and NEON vector
2588 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2589 can provide these registers (requires Linux 2.6.30 or later). Remote
2590 and simulator targets may also provide them.
2592 * New remote packets
2595 Search memory for a sequence of bytes.
2598 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2599 operation over reliable transport links. Use of this packet is
2600 controlled by the `set remote noack-packet' command.
2603 Kill the process with the specified process ID. Use this in preference
2604 to `k' when multiprocess protocol extensions are supported.
2607 Obtains additional operating system information
2611 Read or write additional signal information.
2613 * Removed remote protocol undocumented extension
2615 An undocumented extension to the remote protocol's `S' stop reply
2616 packet that permited the stub to pass a process id was removed.
2617 Remote servers should use the `T' stop reply packet instead.
2619 * GDB now supports multiple function calling conventions according to the
2620 DWARF-2 DW_AT_calling_convention function attribute.
2622 * The SH target utilizes the aforementioned change to distinguish between gcc
2623 and Renesas calling convention. It also adds the new CLI commands
2624 `set/show sh calling-convention'.
2626 * GDB can now read compressed debug sections, as produced by GNU gold
2627 with the --compress-debug-sections=zlib flag.
2629 * 64-bit core files are now supported on AIX.
2631 * Thread switching is now supported on Tru64.
2633 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2634 which will be allocated using malloc later in program execution.
2636 * The qXfer:libraries:read remote procotol packet now allows passing a
2637 list of section offsets.
2639 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2640 conditions handling signals delivered during attach or thread creation
2641 have also been fixed.
2643 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2644 From the user's standpoint, all unqualified instances of True and False
2645 are treated as the standard definitions, regardless of context.
2647 * GDB now parses C++ symbol and type names more flexibly. For
2650 template<typename T> class C { };
2653 GDB will now correctly handle all of:
2655 ptype C<char const *>
2656 ptype C<char const*>
2657 ptype C<const char *>
2658 ptype C<const char*>
2660 * New features in the GDB remote stub, gdbserver
2662 - The "--wrapper" command-line argument tells gdbserver to use a
2663 wrapper program to launch programs for debugging.
2665 - On PowerPC and S/390 targets, it is now possible to use a single
2666 gdbserver executable to debug both 32-bit and 64-bit programs.
2667 (This requires gdbserver itself to be built as a 64-bit executable.)
2669 - gdbserver uses the new noack protocol mode for TCP connections to
2670 reduce communications latency, if also supported and enabled in GDB.
2672 - Support for the sparc64-linux-gnu target is now included in
2675 - The amd64-linux build of gdbserver now supports debugging both
2676 32-bit and 64-bit programs.
2678 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2679 now support hardware watchpoints, and will use them automatically
2684 GDB now has support for scripting using Python. Whether this is
2685 available is determined at configure time.
2687 New GDB commands can now be written in Python.
2689 * Ada tasking support
2691 Ada tasks can now be inspected in GDB. The following commands have
2695 Print the list of Ada tasks.
2697 Print detailed information about task number N.
2699 Print the task number of the current task.
2701 Switch the context of debugging to task number N.
2703 * Support for user-defined prefixed commands. The "define" command can
2704 add new commands to existing prefixes, e.g. "target".
2706 * Multi-inferior, multi-process debugging.
2708 GDB now has generalized support for multi-inferior debugging. See
2709 "Debugging Multiple Inferiors" in the manual for more information.
2710 Although availability still depends on target support, the command
2711 set is more uniform now. The GNU/Linux specific multi-forks support
2712 has been migrated to this new framework. This implied some user
2713 visible changes; see "New commands" and also "Removed commands"
2716 * Target descriptions can now describe the target OS ABI. See the
2717 "Target Description Format" section in the user manual for more
2720 * Target descriptions can now describe "compatible" architectures
2721 to indicate that the target can execute applications for a different
2722 architecture in addition to those for the main target architecture.
2723 See the "Target Description Format" section in the user manual for
2726 * Multi-architecture debugging.
2728 GDB now includes general supports for debugging applications on
2729 hybrid systems that use more than one single processor architecture
2730 at the same time. Each such hybrid architecture still requires
2731 specific support to be added. The only hybrid architecture supported
2732 in this version of GDB is the Cell Broadband Engine.
2734 * GDB now supports integrated debugging of Cell/B.E. applications that
2735 use both the PPU and SPU architectures. To enable support for hybrid
2736 Cell/B.E. debugging, you need to configure GDB to support both the
2737 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2738 --enable-targets configure option.
2740 * Non-stop mode debugging.
2742 For some targets, GDB now supports an optional mode of operation in
2743 which you can examine stopped threads while other threads continue
2744 to execute freely. This is referred to as non-stop mode, with the
2745 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2746 section in the user manual for more information.
2748 To be able to support remote non-stop debugging, a remote stub needs
2749 to implement the non-stop mode remote protocol extensions, as
2750 described in the "Remote Non-Stop" section of the user manual. The
2751 GDB remote stub, gdbserver, has been adjusted to support these
2752 extensions on linux targets.
2754 * New commands (for set/show, see "New options" below)
2756 catch syscall [NAME(S) | NUMBER(S)]
2757 Catch system calls. Arguments, which should be names of system
2758 calls or their numbers, mean catch only those syscalls. Without
2759 arguments, every syscall will be caught. When the inferior issues
2760 any of the specified syscalls, GDB will stop and announce the system
2761 call, both when it is called and when its call returns. This
2762 feature is currently available with a native GDB running on the
2763 Linux Kernel, under the following architectures: x86, x86_64,
2764 PowerPC and PowerPC64.
2766 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2768 Search memory for a sequence of bytes.
2770 maint set python print-stack
2771 maint show python print-stack
2772 Show a stack trace when an error is encountered in a Python script.
2775 Invoke CODE by passing it to the Python interpreter.
2780 These allow macros to be defined, undefined, and listed
2784 Show operating system information about processes.
2787 List the inferiors currently under GDB's control.
2790 Switch focus to inferior number NUM.
2793 Detach from inferior number NUM.
2796 Kill inferior number NUM.
2800 set spu stop-on-load
2801 show spu stop-on-load
2802 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2804 set spu auto-flush-cache
2805 show spu auto-flush-cache
2806 Control whether to automatically flush the software-managed cache
2807 during Cell/B.E. debugging.
2809 set sh calling-convention
2810 show sh calling-convention
2811 Control the calling convention used when calling SH target functions.
2814 show debug timestamp
2815 Control display of timestamps with GDB debugging output.
2817 set disassemble-next-line
2818 show disassemble-next-line
2819 Control display of disassembled source lines or instructions when
2822 set remote noack-packet
2823 show remote noack-packet
2824 Set/show the use of remote protocol QStartNoAckMode packet. See above
2825 under "New remote packets."
2827 set remote query-attached-packet
2828 show remote query-attached-packet
2829 Control use of remote protocol `qAttached' (query-attached) packet.
2831 set remote read-siginfo-object
2832 show remote read-siginfo-object
2833 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2836 set remote write-siginfo-object
2837 show remote write-siginfo-object
2838 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2841 set remote reverse-continue
2842 show remote reverse-continue
2843 Control use of remote protocol 'bc' (reverse-continue) packet.
2845 set remote reverse-step
2846 show remote reverse-step
2847 Control use of remote protocol 'bs' (reverse-step) packet.
2849 set displaced-stepping
2850 show displaced-stepping
2851 Control displaced stepping mode. Displaced stepping is a way to
2852 single-step over breakpoints without removing them from the debuggee.
2853 Also known as "out-of-line single-stepping".
2856 show debug displaced
2857 Control display of debugging info for displaced stepping.
2859 maint set internal-error
2860 maint show internal-error
2861 Control what GDB does when an internal error is detected.
2863 maint set internal-warning
2864 maint show internal-warning
2865 Control what GDB does when an internal warning is detected.
2870 Use a wrapper program to launch programs for debugging.
2872 set multiple-symbols (all|ask|cancel)
2873 show multiple-symbols
2874 The value of this variable can be changed to adjust the debugger behavior
2875 when an expression or a breakpoint location contains an ambiguous symbol
2876 name (an overloaded function name, for instance).
2878 set breakpoint always-inserted
2879 show breakpoint always-inserted
2880 Keep breakpoints always inserted in the target, as opposed to inserting
2881 them when resuming the target, and removing them when the target stops.
2882 This option can improve debugger performance on slow remote targets.
2884 set arm fallback-mode (arm|thumb|auto)
2885 show arm fallback-mode
2886 set arm force-mode (arm|thumb|auto)
2888 These commands control how ARM GDB determines whether instructions
2889 are ARM or Thumb. The default for both settings is auto, which uses
2890 the current CPSR value for instructions without symbols; previous
2891 versions of GDB behaved as if "set arm fallback-mode arm".
2893 set disable-randomization
2894 show disable-randomization
2895 Standalone programs run with the virtual address space randomization enabled
2896 by default on some platforms. This option keeps the addresses stable across
2897 multiple debugging sessions.
2901 Control whether other threads are stopped or not when some thread hits
2906 Requests that asynchronous execution is enabled in the target, if available.
2907 In this case, it's possible to resume target in the background, and interact
2908 with GDB while the target is running. "show target-async" displays the
2909 current state of asynchronous execution of the target.
2911 set target-wide-charset
2912 show target-wide-charset
2913 The target-wide-charset is the name of the character set that GDB
2914 uses when printing characters whose type is wchar_t.
2916 set tcp auto-retry (on|off)
2918 set tcp connect-timeout
2919 show tcp connect-timeout
2920 These commands allow GDB to retry failed TCP connections to a remote stub
2921 with a specified timeout period; this is useful if the stub is launched
2922 in parallel with GDB but may not be ready to accept connections immediately.
2924 set libthread-db-search-path
2925 show libthread-db-search-path
2926 Control list of directories which GDB will search for appropriate
2929 set schedule-multiple (on|off)
2930 show schedule-multiple
2931 Allow GDB to resume all threads of all processes or only threads of
2932 the current process.
2936 Use more aggressive caching for accesses to the stack. This improves
2937 performance of remote debugging (particularly backtraces) without
2938 affecting correctness.
2940 set interactive-mode (on|off|auto)
2941 show interactive-mode
2942 Control whether GDB runs in interactive mode (on) or not (off).
2943 When in interactive mode, GDB waits for the user to answer all
2944 queries. Otherwise, GDB does not wait and assumes the default
2945 answer. When set to auto (the default), GDB determines which
2946 mode to use based on the stdin settings.
2951 For program forks, this is replaced by the new more generic `info
2952 inferiors' command. To list checkpoints, you can still use the
2953 `info checkpoints' command, which was an alias for the `info forks'
2957 Replaced by the new `inferior' command. To switch between
2958 checkpoints, you can still use the `restart' command, which was an
2959 alias for the `fork' command.
2962 This is removed, since some targets don't have a notion of
2963 processes. To switch between processes, you can still use the
2964 `inferior' command using GDB's own inferior number.
2967 For program forks, this is replaced by the new more generic `kill
2968 inferior' command. To delete a checkpoint, you can still use the
2969 `delete checkpoint' command, which was an alias for the `delete
2973 For program forks, this is replaced by the new more generic `detach
2974 inferior' command. To detach a checkpoint, you can still use the
2975 `detach checkpoint' command, which was an alias for the `detach
2978 * New native configurations
2980 x86/x86_64 Darwin i[34567]86-*-darwin*
2982 x86_64 MinGW x86_64-*-mingw*
2986 Lattice Mico32 lm32-*
2987 x86 DICOS i[34567]86-*-dicos*
2988 x86_64 DICOS x86_64-*-dicos*
2991 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2992 (mingw32ce) debugging.
2998 These commands were actually not implemented on any target.
3000 *** Changes in GDB 6.8
3002 * New native configurations
3004 NetBSD/hppa hppa*-*netbsd*
3005 Xtensa GNU/Linux xtensa*-*-linux*
3009 NetBSD/hppa hppa*-*-netbsd*
3010 Xtensa GNU/Lunux xtensa*-*-linux*
3012 * Change in command line behavior -- corefiles vs. process ids.
3014 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3015 attaching to process NUMBER fails, GDB no longer attempts to open a
3016 core file named NUMBER. Attaching to a program using the -c option
3017 is no longer supported. Instead, use the '-p' or '--pid' options.
3019 * GDB can now be built as a native debugger for debugging Windows x86
3020 (mingw32) Portable Executable (PE) programs.
3022 * Pending breakpoints no longer change their number when their address
3025 * GDB now supports breakpoints with multiple locations,
3026 including breakpoints on C++ constructors, inside C++ templates,
3027 and in inlined functions.
3029 * GDB's ability to debug optimized code has been improved. GDB more
3030 accurately identifies function bodies and lexical blocks that occupy
3031 more than one contiguous range of addresses.
3033 * Target descriptions can now describe registers for PowerPC.
3035 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3036 registers on PowerPC targets.
3038 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3039 targets even when the libthread_db library is not available.
3041 * The GDB remote stub, gdbserver, now supports the new file transfer
3042 commands (remote put, remote get, and remote delete).
3044 * The GDB remote stub, gdbserver, now supports run and attach in
3045 extended-remote mode.
3047 * hppa*64*-*-hpux11* target broken
3048 The debugger is unable to start a program and fails with the following
3049 error: "Error trying to get information about dynamic linker".
3050 The gdb-6.7 release is also affected.
3052 * GDB now supports the --enable-targets= configure option to allow
3053 building a single GDB executable that supports multiple remote
3054 target architectures.
3056 * GDB now supports debugging C and C++ programs which use the
3057 Decimal Floating Point extension. In addition, the PowerPC target
3058 now has a set of pseudo-registers to inspect decimal float values
3059 stored in two consecutive float registers.
3061 * The -break-insert MI command can optionally create pending
3064 * Improved support for debugging Ada
3065 Many improvements to the Ada language support have been made. These
3067 - Better support for Ada2005 interface types
3068 - Improved handling of arrays and slices in general
3069 - Better support for Taft-amendment types
3070 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3072 - Improved command completion in Ada
3075 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3080 set print frame-arguments (all|scalars|none)
3081 show print frame-arguments
3082 The value of this variable can be changed to control which argument
3083 values should be printed by the debugger when displaying a frame.
3088 Transfer files to and from a remote target, and delete remote files.
3095 Transfer files to and from a remote target, and delete remote files.
3097 * New remote packets
3104 Open, close, read, write, and delete files on the remote system.
3107 Attach to an existing process on the remote system, in extended-remote
3111 Run a new process on the remote system, in extended-remote mode.
3113 *** Changes in GDB 6.7
3115 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3116 bfd, libiberty and opcodes, as revealed by static analysis donated by
3117 Coverity, Inc. (http://scan.coverity.com).
3119 * When looking up multiply-defined global symbols, GDB will now prefer the
3120 symbol definition in the current shared library if it was built using the
3121 -Bsymbolic linker option.
3123 * When the Text User Interface (TUI) is not configured, GDB will now
3124 recognize the -tui command-line option and print a message that the TUI
3127 * The GDB remote stub, gdbserver, now has lower overhead for high
3128 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3130 * GDB for MIPS targets now autodetects whether a remote target provides
3131 32-bit or 64-bit register values.
3133 * Support for C++ member pointers has been improved.
3135 * GDB now understands XML target descriptions, which specify the
3136 target's overall architecture. GDB can read a description from
3137 a local file or over the remote serial protocol.
3139 * Vectors of single-byte data use a new integer type which is not
3140 automatically displayed as character or string data.
3142 * The /s format now works with the print command. It displays
3143 arrays of single-byte integers and pointers to single-byte integers
3146 * Target descriptions can now describe target-specific registers,
3147 for architectures which have implemented the support (currently
3148 only ARM, M68K, and MIPS).
3150 * GDB and the GDB remote stub, gdbserver, now support the XScale
3153 * The GDB remote stub, gdbserver, has been updated to support
3154 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3155 has been rewritten to use the standard GDB remote protocol.
3157 * GDB can now step into C++ functions which are called through thunks.
3159 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3161 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3162 layout. It also supports a TextSeg= and DataSeg= response when only
3163 segment base addresses (rather than offsets) are available.
3165 * The /i format now outputs any trailing branch delay slot instructions
3166 immediately following the last instruction within the count specified.
3168 * The GDB remote protocol "T" stop reply packet now supports a
3169 "library" response. Combined with the new "qXfer:libraries:read"
3170 packet, this response allows GDB to debug shared libraries on targets
3171 where the operating system manages the list of loaded libraries (e.g.
3172 Windows and SymbianOS).
3174 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3175 (DLLs) on Windows and Windows CE targets.
3177 * GDB now supports a faster verification that a .debug file matches its binary
3178 according to its build-id signature, if the signature is present.
3184 Enable or disable hardware flow control (RTS/CTS) on the serial port
3185 when debugging using remote targets.
3187 set mem inaccessible-by-default
3188 show mem inaccessible-by-default
3189 If the target supplies a memory map, for instance via the remote
3190 protocol's "qXfer:memory-map:read" packet, setting this variable
3191 prevents GDB from accessing memory outside the memory map. This
3192 is useful for targets with memory mapped registers or which react
3193 badly to accesses of unmapped address space.
3195 set breakpoint auto-hw
3196 show breakpoint auto-hw
3197 If the target supplies a memory map, for instance via the remote
3198 protocol's "qXfer:memory-map:read" packet, setting this variable
3199 lets GDB use hardware breakpoints automatically for memory regions
3200 where it can not use software breakpoints. This covers both the
3201 "break" command and internal breakpoints used for other commands
3202 including "next" and "finish".
3205 catch exception unhandled
3206 Stop the program execution when Ada exceptions are raised.
3209 Stop the program execution when an Ada assertion failed.
3213 Set an alternate system root for target files. This is a more
3214 general version of "set solib-absolute-prefix", which is now
3215 an alias to "set sysroot".
3218 Provide extended SPU facility status information. This set of
3219 commands is available only when debugging the Cell/B.E. SPU
3222 * New native configurations
3224 OpenBSD/sh sh*-*openbsd*
3227 unset tdesc filename
3229 Use the specified local file as an XML target description, and do
3230 not query the target for its built-in description.
3234 OpenBSD/sh sh*-*-openbsd*
3235 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3236 Toshiba Media Processor mep-elf
3238 * New remote packets
3241 Ignore the specified signals; pass them directly to the debugged program
3242 without stopping other threads or reporting them to GDB.
3244 qXfer:features:read:
3245 Read an XML target description from the target, which describes its
3250 Read or write contents of an spufs file on the target system. These
3251 packets are available only on the Cell/B.E. SPU architecture.
3253 qXfer:libraries:read:
3254 Report the loaded shared libraries. Combined with new "T" packet
3255 response, this packet allows GDB to debug shared libraries on
3256 targets where the operating system manages the list of loaded
3257 libraries (e.g. Windows and SymbianOS).
3261 Support for these obsolete configurations has been removed.
3269 i[34567]86-*-lynxos*
3270 i[34567]86-*-netware*
3271 i[34567]86-*-sco3.2v5*
3272 i[34567]86-*-sco3.2v4*
3274 i[34567]86-*-sysv4.2*
3277 i[34567]86-*-unixware2*
3278 i[34567]86-*-unixware*
3287 * Other removed features
3294 Various m68k-only ROM monitors.
3301 Various Renesas ROM monitors and debugging interfaces for SH and
3306 Support for a Macraigor serial interface to on-chip debugging.
3307 GDB does not directly support the newer parallel or USB
3312 A debug information format. The predecessor to DWARF 2 and
3313 DWARF 3, which are still supported.
3315 Support for the HP aCC compiler on HP-UX/PA-RISC
3317 SOM-encapsulated symbolic debugging information, automatic
3318 invocation of pxdb, and the aCC custom C++ ABI. This does not
3319 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3320 with aCC can still be debugged on an assembly level.
3322 MIPS ".pdr" sections
3324 A MIPS-specific format used to describe stack frame layout
3325 in debugging information.
3329 GDB could work with an older version of Guile to debug
3330 the interpreter and Scheme programs running in it.
3332 set mips stack-arg-size
3333 set mips saved-gpreg-size
3335 Use "set mips abi" to control parameter passing for MIPS.
3337 *** Changes in GDB 6.6
3342 Cell Broadband Engine SPU spu-elf
3344 * GDB can now be configured as a cross-debugger targeting native Windows
3345 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3346 running on a Windows system over TCP/IP to debug Windows programs.
3348 * The GDB remote stub, gdbserver, has been updated to support Windows and
3349 Cygwin debugging. Both single-threaded and multi-threaded programs are
3352 * The "set trust-readonly-sections" command works again. This command was
3353 broken in GDB 6.3, 6.4, and 6.5.
3355 * The "load" command now supports writing to flash memory, if the remote
3356 stub provides the required support.
3358 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3359 longer requires symbolic debug information (e.g. DWARF-2).
3364 unset substitute-path
3365 show substitute-path
3366 Manage a list of substitution rules that GDB uses to rewrite the name
3367 of the directories where the sources are located. This can be useful
3368 for instance when the sources were moved to a different location
3369 between compilation and debugging.
3373 Print each CLI command as it is executed. Each command is prefixed with
3374 a number of `+' symbols representing the nesting depth.
3375 The source command now has a `-v' option to enable the same feature.
3379 The ARM Demon monitor support (RDP protocol, "target rdp").
3381 Kernel Object Display, an embedded debugging feature which only worked with
3382 an obsolete version of Cisco IOS.
3384 The 'set download-write-size' and 'show download-write-size' commands.
3386 * New remote packets
3389 Tell a stub about GDB client features, and request remote target features.
3390 The first feature implemented is PacketSize, which allows the target to
3391 specify the size of packets it can handle - to minimize the number of
3392 packets required and improve performance when connected to a remote
3396 Fetch an OS auxilliary vector from the remote stub. This packet is a
3397 more efficient replacement for qPart:auxv:read.
3399 qXfer:memory-map:read:
3400 Fetch a memory map from the remote stub, including information about
3401 RAM, ROM, and flash memory devices.
3406 Erase and program a flash memory device.
3408 * Removed remote packets
3411 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3412 used it, and only gdbserver implemented it.
3414 *** Changes in GDB 6.5
3418 Renesas M32C/M16C m32c-elf
3420 Morpho Technologies ms1 ms1-elf
3424 init-if-undefined Initialize a convenience variable, but
3425 only if it doesn't already have a value.
3427 The following commands are presently only implemented for native GNU/Linux:
3429 checkpoint Save a snapshot of the program state.
3431 restart <n> Return the program state to a
3432 previously saved state.
3434 info checkpoints List currently saved checkpoints.
3436 delete-checkpoint <n> Delete a previously saved checkpoint.
3438 set|show detach-on-fork Tell gdb whether to detach from a newly
3439 forked process, or to keep debugging it.
3441 info forks List forks of the user program that
3442 are available to be debugged.
3444 fork <n> Switch to debugging one of several
3445 forks of the user program that are
3446 available to be debugged.
3448 delete-fork <n> Delete a fork from the list of forks
3449 that are available to be debugged (and
3450 kill the forked process).
3452 detach-fork <n> Delete a fork from the list of forks
3453 that are available to be debugged (and
3454 allow the process to continue).
3458 Morpho Technologies ms2 ms1-elf
3460 * Improved Windows host support
3462 GDB now builds as a cross debugger hosted on i686-mingw32, including
3463 native console support, and remote communications using either
3464 network sockets or serial ports.
3466 * Improved Modula-2 language support
3468 GDB can now print most types in the Modula-2 syntax. This includes:
3469 basic types, set types, record types, enumerated types, range types,
3470 pointer types and ARRAY types. Procedure var parameters are correctly
3471 printed and hexadecimal addresses and character constants are also
3472 written in the Modula-2 syntax. Best results can be obtained by using
3473 GNU Modula-2 together with the -gdwarf-2 command line option.
3477 The ARM rdi-share module.
3479 The Netware NLM debug server.
3481 *** Changes in GDB 6.4
3483 * New native configurations
3485 OpenBSD/arm arm*-*-openbsd*
3486 OpenBSD/mips64 mips64-*-openbsd*
3490 Morpho Technologies ms1 ms1-elf
3492 * New command line options
3494 --batch-silent As for --batch, but totally silent.
3495 --return-child-result The debugger will exist with the same value
3496 the child (debugged) program exited with.
3497 --eval-command COMMAND, -ex COMMAND
3498 Execute a single GDB CLI command. This may be
3499 specified multiple times and in conjunction
3500 with the --command (-x) option.
3502 * Deprecated commands removed
3504 The following commands, that were deprecated in 2000, have been
3508 set|show arm disassembly-flavor set|show arm disassembler
3509 othernames set arm disassembler
3510 set|show remotedebug set|show debug remote
3511 set|show archdebug set|show debug arch
3512 set|show eventdebug set|show debug event
3515 * New BSD user-level threads support
3517 It is now possible to debug programs using the user-level threads
3518 library on OpenBSD and FreeBSD. Currently supported (target)
3521 FreeBSD/amd64 x86_64-*-freebsd*
3522 FreeBSD/i386 i386-*-freebsd*
3523 OpenBSD/i386 i386-*-openbsd*
3525 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3526 are not yet supported.
3528 * New support for Matsushita MN10300 w/sim added
3529 (Work in progress). mn10300-elf.
3531 * REMOVED configurations and files
3533 VxWorks and the XDR protocol *-*-vxworks
3534 Motorola MCORE mcore-*-*
3535 National Semiconductor NS32000 ns32k-*-*
3537 * New "set print array-indexes" command
3539 After turning this setting "on", GDB prints the index of each element
3540 when displaying arrays. The default is "off" to preserve the previous
3543 * VAX floating point support
3545 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3547 * User-defined command support
3549 In addition to using $arg0..$arg9 for argument passing, it is now possible
3550 to use $argc to determine now many arguments have been passed. See the
3551 section on user-defined commands in the user manual for more information.
3553 *** Changes in GDB 6.3:
3555 * New command line option
3557 GDB now accepts -l followed by a number to set the timeout for remote
3560 * GDB works with GCC -feliminate-dwarf2-dups
3562 GDB now supports a more compact representation of DWARF-2 debug
3563 information using DW_FORM_ref_addr references. These are produced
3564 by GCC with the option -feliminate-dwarf2-dups and also by some
3565 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3566 to use -feliminate-dwarf2-dups.
3568 * Internationalization
3570 When supported by the host system, GDB will be built with
3571 internationalization (libintl). The task of marking up the sources is
3572 continued, we're looking forward to our first translation.
3576 Initial support for debugging programs compiled with the GNAT
3577 implementation of the Ada programming language has been integrated
3578 into GDB. In this release, support is limited to expression evaluation.
3580 * New native configurations
3582 GNU/Linux/m32r m32r-*-linux-gnu
3586 GDB's remote protocol now includes support for the 'p' packet. This
3587 packet is used to fetch individual registers from a remote inferior.
3589 * END-OF-LIFE registers[] compatibility module
3591 GDB's internal register infrastructure has been completely rewritten.
3592 The new infrastructure making possible the implementation of key new
3593 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3596 GDB 6.3 will be the last release to include the the registers[]
3597 compatibility module that allowed out-of-date configurations to
3598 continue to work. This change directly impacts the following
3608 powerpc bdm protocol
3610 Unless there is activity to revive these configurations, they will be
3611 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3613 * OBSOLETE configurations and files
3615 Configurations that have been declared obsolete in this release have
3616 been commented out. Unless there is activity to revive these
3617 configurations, the next release of GDB will have their sources
3618 permanently REMOVED.
3627 *** Changes in GDB 6.2.1:
3629 * MIPS `break main; run' gave an heuristic-fence-post warning
3631 When attempting to run even a simple program, a warning about
3632 heuristic-fence-post being hit would be reported. This problem has
3635 * MIPS IRIX 'long double' crashed GDB
3637 When examining a long double variable, GDB would get a segmentation
3638 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3639 IRIX long double values).
3643 A bug in the VAX stack code was causing problems with the "next"
3644 command. This problem has been fixed.
3646 *** Changes in GDB 6.2:
3648 * Fix for ``many threads''
3650 On GNU/Linux systems that use the NPTL threads library, a program
3651 rapidly creating and deleting threads would confuse GDB leading to the
3654 ptrace: No such process.
3655 thread_db_get_info: cannot get thread info: generic error
3657 This problem has been fixed.
3659 * "-async" and "-noasync" options removed.
3661 Support for the broken "-noasync" option has been removed (it caused
3664 * New ``start'' command.
3666 This command runs the program until the begining of the main procedure.
3668 * New BSD Kernel Data Access Library (libkvm) interface
3670 Using ``target kvm'' it is now possible to debug kernel core dumps and
3671 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3672 platforms. Currently supported (native-only) configurations are:
3674 FreeBSD/amd64 x86_64-*-freebsd*
3675 FreeBSD/i386 i?86-*-freebsd*
3676 NetBSD/i386 i?86-*-netbsd*
3677 NetBSD/m68k m68*-*-netbsd*
3678 NetBSD/sparc sparc-*-netbsd*
3679 OpenBSD/amd64 x86_64-*-openbsd*
3680 OpenBSD/i386 i?86-*-openbsd*
3681 OpenBSD/m68k m68*-openbsd*
3682 OpenBSD/sparc sparc-*-openbsd*
3684 * Signal trampoline code overhauled
3686 Many generic problems with GDB's signal handling code have been fixed.
3687 These include: backtraces through non-contiguous stacks; recognition
3688 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3689 call; backtrace through a signal trampoline; step into and out of
3690 signal handlers; and single-stepping in the signal trampoline.
3692 Please note that kernel bugs are a limiting factor here. These
3693 features have been shown to work on an s390 GNU/Linux system that
3694 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3696 * Cygwin support for DWARF 2 added.
3698 * New native configurations
3700 GNU/Linux/hppa hppa*-*-linux*
3701 OpenBSD/hppa hppa*-*-openbsd*
3702 OpenBSD/m68k m68*-*-openbsd*
3703 OpenBSD/m88k m88*-*-openbsd*
3704 OpenBSD/powerpc powerpc-*-openbsd*
3705 NetBSD/vax vax-*-netbsd*
3706 OpenBSD/vax vax-*-openbsd*
3708 * END-OF-LIFE frame compatibility module
3710 GDB's internal frame infrastructure has been completely rewritten.
3711 The new infrastructure making it possible to support key new features
3712 including DWARF 2 Call Frame Information. To aid in the task of
3713 migrating old configurations to this new infrastructure, a
3714 compatibility module, that allowed old configurations to continue to
3715 work, was also included.
3717 GDB 6.2 will be the last release to include this frame compatibility
3718 module. This change directly impacts the following configurations:
3728 Unless there is activity to revive these configurations, they will be
3729 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3731 * REMOVED configurations and files
3733 Sun 3, running SunOS 3 m68*-*-sunos3*
3734 Sun 3, running SunOS 4 m68*-*-sunos4*
3735 Sun 2, running SunOS 3 m68000-*-sunos3*
3736 Sun 2, running SunOS 4 m68000-*-sunos4*
3737 Motorola 680x0 running LynxOS m68*-*-lynxos*
3738 AT&T 3b1/Unix pc m68*-att-*
3739 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3740 decstation mips-dec-* mips-little-*
3741 riscos mips-*-riscos* mips-*-sysv*
3742 sonymips mips-sony-*
3743 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3745 *** Changes in GDB 6.1.1:
3747 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3749 The TUI (Text-mode User Interface) is now built as part of a default
3750 GDB configuration. It is enabled by either selecting the TUI with the
3751 command line option "-i=tui" or by running the separate "gdbtui"
3752 program. For more information on the TUI, see the manual "Debugging
3755 * Pending breakpoint support (also included in GDB 6.1)
3757 Support has been added to allow you to specify breakpoints in shared
3758 libraries that have not yet been loaded. If a breakpoint location
3759 cannot be found, and the "breakpoint pending" option is set to auto,
3760 GDB queries you if you wish to make the breakpoint pending on a future
3761 shared-library load. If and when GDB resolves the breakpoint symbol,
3762 the pending breakpoint is removed as one or more regular breakpoints
3765 Pending breakpoints are very useful for GCJ Java debugging.
3767 * Fixed ISO-C build problems
3769 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3770 non ISO-C code that stopped them being built using a more strict ISO-C
3771 compiler (e.g., IBM's C compiler).
3773 * Fixed build problem on IRIX 5
3775 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3776 wasn't able to compile compile on an IRIX 5 system.
3778 * Added execute permission to gdb/gdbserver/configure
3780 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3781 permission. This bug would cause configure to fail on a number of
3782 systems (Solaris, IRIX). Ref: server/519.
3784 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3786 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3787 has been updated to use constant array sizes.
3789 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3791 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3792 its generated DWARF Call Frame Info. This encoding was causing GDB to
3793 panic, that panic has been fixed. Ref: gdb/1628.
3795 * Fixed a problem when examining parameters in shared library code.
3797 When examining parameters in optimized shared library code generated
3798 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3799 not available''. GDB now correctly displays the variable's value.
3801 *** Changes in GDB 6.1:
3803 * Removed --with-mmalloc
3805 Support for the mmalloc memory manager has been removed, as it
3806 conflicted with the internal gdb byte cache.
3808 * Changes in AMD64 configurations
3810 The AMD64 target now includes the %cs and %ss registers. As a result
3811 the AMD64 remote protocol has changed; this affects the floating-point
3812 and SSE registers. If you rely on those registers for your debugging,
3813 you should upgrade gdbserver on the remote side.
3815 * Revised SPARC target
3817 The SPARC target has been completely revised, incorporating the
3818 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3819 support for LynxOS and SunOS 4 has been dropped. Calling functions
3820 from within GDB on operating systems with a non-executable stack
3821 (Solaris, OpenBSD) now works.
3825 GDB has a new C++ demangler which does a better job on the mangled
3826 names generated by current versions of g++. It also runs faster, so
3827 with this and other changes gdb should now start faster on large C++
3830 * DWARF 2 Location Expressions
3832 GDB support for location expressions has been extended to support function
3833 arguments and frame bases. Older versions of GDB could crash when they
3836 * C++ nested types and namespaces
3838 GDB's support for nested types and namespaces in C++ has been
3839 improved, especially if you use the DWARF 2 debugging format. (This
3840 is the default for recent versions of GCC on most platforms.)
3841 Specifically, if you have a class "Inner" defined within a class or
3842 namespace "Outer", then GDB realizes that the class's name is
3843 "Outer::Inner", not simply "Inner". This should greatly reduce the
3844 frequency of complaints about not finding RTTI symbols. In addition,
3845 if you are stopped at inside of a function defined within a namespace,
3846 GDB modifies its name lookup accordingly.
3848 * New native configurations
3850 NetBSD/amd64 x86_64-*-netbsd*
3851 OpenBSD/amd64 x86_64-*-openbsd*
3852 OpenBSD/alpha alpha*-*-openbsd*
3853 OpenBSD/sparc sparc-*-openbsd*
3854 OpenBSD/sparc64 sparc64-*-openbsd*
3856 * New debugging protocols
3858 M32R with SDI protocol m32r-*-elf*
3860 * "set prompt-escape-char" command deleted.
3862 The command "set prompt-escape-char" has been deleted. This command,
3863 and its very obscure effet on GDB's prompt, was never documented,
3864 tested, nor mentioned in the NEWS file.
3866 * OBSOLETE configurations and files
3868 Configurations that have been declared obsolete in this release have
3869 been commented out. Unless there is activity to revive these
3870 configurations, the next release of GDB will have their sources
3871 permanently REMOVED.
3873 Sun 3, running SunOS 3 m68*-*-sunos3*
3874 Sun 3, running SunOS 4 m68*-*-sunos4*
3875 Sun 2, running SunOS 3 m68000-*-sunos3*
3876 Sun 2, running SunOS 4 m68000-*-sunos4*
3877 Motorola 680x0 running LynxOS m68*-*-lynxos*
3878 AT&T 3b1/Unix pc m68*-att-*
3879 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3880 decstation mips-dec-* mips-little-*
3881 riscos mips-*-riscos* mips-*-sysv*
3882 sonymips mips-sony-*
3883 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3885 * REMOVED configurations and files
3887 SGI Irix-4.x mips-sgi-irix4 or iris4
3888 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3889 Z8000 simulator z8k-zilog-none or z8ksim
3890 Matsushita MN10200 w/simulator mn10200-*-*
3891 H8/500 simulator h8500-hitachi-hms or h8500hms
3892 HP/PA running BSD hppa*-*-bsd*
3893 HP/PA running OSF/1 hppa*-*-osf*
3894 HP/PA Pro target hppa*-*-pro*
3895 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3896 386BSD i[3456]86-*-bsd*
3897 Sequent family i[3456]86-sequent-sysv4*
3898 i[3456]86-sequent-sysv*
3899 i[3456]86-sequent-bsd*
3900 SPARC running LynxOS sparc-*-lynxos*
3901 SPARC running SunOS 4 sparc-*-sunos4*
3902 Tsqware Sparclet sparclet-*-*
3903 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3905 *** Changes in GDB 6.0:
3909 Support for debugging the Objective-C programming language has been
3910 integrated into GDB.
3912 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3914 DWARF 2's Call Frame Information makes available compiler generated
3915 information that more exactly describes the program's run-time stack.
3916 By using this information, GDB is able to provide more robust stack
3919 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3920 have been updated to use a new backtrace mechanism which includes
3921 DWARF 2 CFI support.
3925 GDB's remote protocol has been extended to include support for hosted
3926 file I/O (where the remote target uses GDB's file system). See GDB's
3927 remote protocol documentation for details.
3929 * All targets using the new architecture framework.
3931 All of GDB's targets have been updated to use the new internal
3932 architecture framework. The way is now open for future GDB releases
3933 to include cross-architecture native debugging support (i386 on amd64,
3936 * GNU/Linux's Thread Local Storage (TLS)
3938 GDB now includes support for for the GNU/Linux implementation of
3939 per-thread variables.
3941 * GNU/Linux's Native POSIX Thread Library (NPTL)
3943 GDB's thread code has been updated to work with either the new
3944 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3946 * Separate debug info.
3948 GDB, in conjunction with BINUTILS, now supports a mechanism for
3949 automatically loading debug information from a separate file. Instead
3950 of shipping full debug and non-debug versions of system libraries,
3951 system integrators can now instead ship just the stripped libraries
3952 and optional debug files.
3954 * DWARF 2 Location Expressions
3956 DWARF 2 Location Expressions allow the compiler to more completely
3957 describe the location of variables (even in optimized code) to the
3960 GDB now includes preliminary support for location expressions (support
3961 for DW_OP_piece is still missing).
3965 A number of long standing bugs that caused GDB to die while starting a
3966 Java application have been fixed. GDB's Java support is now
3967 considered "useable".
3969 * GNU/Linux support for fork, vfork, and exec.
3971 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3972 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3975 * GDB supports logging output to a file
3977 There are two new commands, "set logging" and "show logging", which can be
3978 used to capture GDB's output to a file.
3980 * The meaning of "detach" has changed for gdbserver
3982 The "detach" command will now resume the application, as documented. To
3983 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3986 * d10v, m68hc11 `regs' command deprecated
3988 The `info registers' command has been updated so that it displays the
3989 registers using a format identical to the old `regs' command.
3993 A new command, "maint set profile on/off", has been added. This command can
3994 be used to enable or disable profiling while running GDB, to profile a
3995 session or a set of commands. In addition there is a new configure switch,
3996 "--enable-profiling", which will cause GDB to be compiled with profiling
3997 data, for more informative profiling results.
3999 * Default MI syntax changed to "mi2".
4001 The default MI (machine interface) syntax, enabled by the command line
4002 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4003 "mi1", can be enabled by specifying the option "-i=mi1".
4005 Support for the original "mi0" syntax (included in GDB 5.0) has been
4008 Fix for gdb/192: removed extraneous space when displaying frame level.
4009 Fix for gdb/672: update changelist is now output in mi list format.
4010 Fix for gdb/702: a -var-assign that updates the value now shows up
4011 in a subsequent -var-update.
4013 * New native configurations.
4015 FreeBSD/amd64 x86_64-*-freebsd*
4017 * Multi-arched targets.
4019 HP/PA HPUX11 hppa*-*-hpux*
4020 Renesas M32R/D w/simulator m32r-*-elf*
4022 * OBSOLETE configurations and files
4024 Configurations that have been declared obsolete in this release have
4025 been commented out. Unless there is activity to revive these
4026 configurations, the next release of GDB will have their sources
4027 permanently REMOVED.
4029 Z8000 simulator z8k-zilog-none or z8ksim
4030 Matsushita MN10200 w/simulator mn10200-*-*
4031 H8/500 simulator h8500-hitachi-hms or h8500hms
4032 HP/PA running BSD hppa*-*-bsd*
4033 HP/PA running OSF/1 hppa*-*-osf*
4034 HP/PA Pro target hppa*-*-pro*
4035 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4036 Sequent family i[3456]86-sequent-sysv4*
4037 i[3456]86-sequent-sysv*
4038 i[3456]86-sequent-bsd*
4039 Tsqware Sparclet sparclet-*-*
4040 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4042 * REMOVED configurations and files
4045 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4046 IBM AIX PS/2 i[3456]86-*-aix
4047 i386 running Mach 3.0 i[3456]86-*-mach3*
4048 i386 running Mach i[3456]86-*-mach*
4049 i386 running OSF/1 i[3456]86-*osf1mk*
4050 HP/Apollo 68k Family m68*-apollo*-sysv*,
4052 m68*-hp-bsd*, m68*-hp-hpux*
4053 Argonaut Risc Chip (ARC) arc-*-*
4054 Mitsubishi D30V d30v-*-*
4055 Fujitsu FR30 fr30-*-elf*
4056 OS/9000 i[34]86-*-os9k
4057 I960 with MON960 i960-*-coff
4059 * MIPS $fp behavior changed
4061 The convenience variable $fp, for the MIPS, now consistently returns
4062 the address of the current frame's base. Previously, depending on the
4063 context, $fp could refer to either $sp or the current frame's base
4064 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4065 The GNU Source-Level Debugger''.
4067 *** Changes in GDB 5.3:
4069 * GNU/Linux shared library multi-threaded performance improved.
4071 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4072 `/proc', in preference to `ptrace' for memory reads. This may result
4073 in an improvement in the start-up time of multi-threaded, shared
4074 library applications when run under GDB. One GDB user writes: ``loads
4075 shared libs like mad''.
4077 * ``gdbserver'' now supports multi-threaded applications on some targets
4079 Support for debugging multi-threaded applications which use
4080 the GNU/Linux LinuxThreads package has been added for
4081 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4082 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4084 * GDB now supports C/C++ preprocessor macros.
4086 GDB now expands preprocessor macro invocations in C/C++ expressions,
4087 and provides various commands for showing macro definitions and how
4090 The new command `macro expand EXPRESSION' expands any macro
4091 invocations in expression, and shows the result.
4093 The new command `show macro MACRO-NAME' shows the definition of the
4094 macro named MACRO-NAME, and where it was defined.
4096 Most compilers don't include information about macros in the debugging
4097 information by default. In GCC 3.1, for example, you need to compile
4098 your program with the options `-gdwarf-2 -g3'. If the macro
4099 information is present in the executable, GDB will read it.
4101 * Multi-arched targets.
4103 DEC Alpha (partial) alpha*-*-*
4104 DEC VAX (partial) vax-*-*
4106 National Semiconductor NS32000 (partial) ns32k-*-*
4107 Motorola 68000 (partial) m68k-*-*
4108 Motorola MCORE mcore-*-*
4112 Fujitsu FRV architecture added by Red Hat frv*-*-*
4115 * New native configurations
4117 Alpha NetBSD alpha*-*-netbsd*
4118 SH NetBSD sh*-*-netbsdelf*
4119 MIPS NetBSD mips*-*-netbsd*
4120 UltraSPARC NetBSD sparc64-*-netbsd*
4122 * OBSOLETE configurations and files
4124 Configurations that have been declared obsolete in this release have
4125 been commented out. Unless there is activity to revive these
4126 configurations, the next release of GDB will have their sources
4127 permanently REMOVED.
4129 Mitsubishi D30V d30v-*-*
4130 OS/9000 i[34]86-*-os9k
4131 IBM AIX PS/2 i[3456]86-*-aix
4132 Fujitsu FR30 fr30-*-elf*
4133 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4134 Argonaut Risc Chip (ARC) arc-*-*
4135 i386 running Mach 3.0 i[3456]86-*-mach3*
4136 i386 running Mach i[3456]86-*-mach*
4137 i386 running OSF/1 i[3456]86-*osf1mk*
4138 HP/Apollo 68k Family m68*-apollo*-sysv*,
4140 m68*-hp-bsd*, m68*-hp-hpux*
4141 I960 with MON960 i960-*-coff
4143 * OBSOLETE languages
4145 CHILL, a Pascal like language used by telecommunications companies.
4147 * REMOVED configurations and files
4149 AMD 29k family via UDI a29k-amd-udi, udi29k
4150 A29K VxWorks a29k-*-vxworks
4151 AMD 29000 embedded, using EBMON a29k-none-none
4152 AMD 29000 embedded with COFF a29k-none-coff
4153 AMD 29000 embedded with a.out a29k-none-aout
4155 testsuite/gdb.hp/gdb.threads-hp/ directory
4157 * New command "set max-user-call-depth <nnn>"
4159 This command allows the user to limit the call depth of user-defined
4160 commands. The default is 1024.
4162 * Changes in FreeBSD/i386 native debugging.
4164 Support for the "generate-core-file" has been added.
4166 * New commands "dump", "append", and "restore".
4168 These commands allow data to be copied from target memory
4169 to a bfd-format or binary file (dump and append), and back
4170 from a file into memory (restore).
4172 * Improved "next/step" support on multi-processor Alpha Tru64.
4174 The previous single-step mechanism could cause unpredictable problems,
4175 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4176 of a software single-step mechanism prevents this.
4178 *** Changes in GDB 5.2.1:
4186 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4187 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4188 Fix, by Joel Brobecker imported from mainline.
4190 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4191 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4192 Fix, by Fred Fish, imported from mainline.
4194 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4195 Surprisingly enough, it works now.
4196 By Michal Ludvig, imported from mainline.
4198 i386 hardware watchpoint support:
4199 avoid misses on second run for some targets.
4200 By Pierre Muller, imported from mainline.
4202 *** Changes in GDB 5.2:
4204 * New command "set trust-readonly-sections on[off]".
4206 This command is a hint that tells gdb that read-only sections
4207 really are read-only (ie. that their contents will not change).
4208 In this mode, gdb will go to the object file rather than the
4209 target to read memory from read-only sections (such as ".text").
4210 This can be a significant performance improvement on some
4211 (notably embedded) targets.
4213 * New command "generate-core-file" (or "gcore").
4215 This new gdb command allows the user to drop a core file of the child
4216 process state at any time. So far it's been implemented only for
4217 GNU/Linux and Solaris, but should be relatively easily ported to other
4218 hosts. Argument is core file name (defaults to core.<pid>).
4220 * New command line option
4222 GDB now accepts --pid or -p followed by a process id.
4224 * Change in command line behavior -- corefiles vs. process ids.
4226 There is a subtle behavior in the way in which GDB handles
4227 command line arguments. The first non-flag argument is always
4228 a program to debug, but the second non-flag argument may either
4229 be a corefile or a process id. Previously, GDB would attempt to
4230 open the second argument as a corefile, and if that failed, would
4231 issue a superfluous error message and then attempt to attach it as
4232 a process. Now, if the second argument begins with a non-digit,
4233 it will be treated as a corefile. If it begins with a digit,
4234 GDB will attempt to attach it as a process, and if no such process
4235 is found, will then attempt to open it as a corefile.
4237 * Changes in ARM configurations.
4239 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4240 configuration is fully multi-arch.
4242 * New native configurations
4244 ARM NetBSD arm*-*-netbsd*
4245 x86 OpenBSD i[3456]86-*-openbsd*
4246 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4247 Sparc64 running FreeBSD sparc64-*-freebsd*
4251 Sanyo XStormy16 xstormy16-elf
4253 * OBSOLETE configurations and files
4255 Configurations that have been declared obsolete in this release have
4256 been commented out. Unless there is activity to revive these
4257 configurations, the next release of GDB will have their sources
4258 permanently REMOVED.
4260 AMD 29k family via UDI a29k-amd-udi, udi29k
4261 A29K VxWorks a29k-*-vxworks
4262 AMD 29000 embedded, using EBMON a29k-none-none
4263 AMD 29000 embedded with COFF a29k-none-coff
4264 AMD 29000 embedded with a.out a29k-none-aout
4266 testsuite/gdb.hp/gdb.threads-hp/ directory
4268 * REMOVED configurations and files
4270 TI TMS320C80 tic80-*-*
4272 PowerPC Solaris powerpcle-*-solaris*
4273 PowerPC Windows NT powerpcle-*-cygwin32
4274 PowerPC Netware powerpc-*-netware*
4275 Harris/CXUX m88k m88*-harris-cxux*
4276 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4277 ns32k-utek-sysv* ns32k-utek-*
4278 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4279 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4280 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4281 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4282 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4284 * Changes to command line processing
4286 The new `--args' feature can be used to specify command-line arguments
4287 for the inferior from gdb's command line.
4289 * Changes to key bindings
4291 There is a new `operate-and-get-next' function bound to `C-o'.
4293 *** Changes in GDB 5.1.1
4295 Fix compile problem on DJGPP.
4297 Fix a problem with floating-point registers on the i386 being
4300 Fix to stop GDB crashing on .debug_str debug info.
4302 Numerous documentation fixes.
4304 Numerous testsuite fixes.
4306 *** Changes in GDB 5.1:
4308 * New native configurations
4310 Alpha FreeBSD alpha*-*-freebsd*
4311 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4312 MIPS GNU/Linux mips*-*-linux*
4313 MIPS SGI Irix 6.x mips*-sgi-irix6*
4314 ia64 AIX ia64-*-aix*
4315 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4319 Motorola 68HC11 and 68HC12 m68hc11-elf
4321 UltraSparc running GNU/Linux sparc64-*-linux*
4323 * OBSOLETE configurations and files
4325 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4326 Harris/CXUX m88k m88*-harris-cxux*
4327 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4328 ns32k-utek-sysv* ns32k-utek-*
4329 TI TMS320C80 tic80-*-*
4331 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4332 PowerPC Solaris powerpcle-*-solaris*
4333 PowerPC Windows NT powerpcle-*-cygwin32
4334 PowerPC Netware powerpc-*-netware*
4335 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4336 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4337 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4338 Apple Macintosh (MPW) host N/A
4340 stuff.c (Program to stuff files into a specially prepared space in kdb)
4341 kdb-start.c (Main loop for the standalone kernel debugger)
4343 Configurations that have been declared obsolete in this release have
4344 been commented out. Unless there is activity to revive these
4345 configurations, the next release of GDB will have their sources
4346 permanently REMOVED.
4348 * REMOVED configurations and files
4350 Altos 3068 m68*-altos-*
4351 Convex c1-*-*, c2-*-*
4353 ARM RISCix arm-*-* (as host)
4357 * GDB has been converted to ISO C.
4359 GDB's source code has been converted to ISO C. In particular, the
4360 sources are fully protoized, and rely on standard headers being
4365 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4367 * The MI enabled by default.
4369 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4370 revised and enabled by default. Packages which use GDB as a debugging
4371 engine behind a UI or another front end are encouraged to switch to
4372 using the GDB/MI interface, instead of the old annotations interface
4373 which is now deprecated.
4375 * Support for debugging Pascal programs.
4377 GDB now includes support for debugging Pascal programs. The following
4378 main features are supported:
4380 - Pascal-specific data types such as sets;
4382 - automatic recognition of Pascal sources based on file-name
4385 - Pascal-style display of data types, variables, and functions;
4387 - a Pascal expression parser.
4389 However, some important features are not yet supported.
4391 - Pascal string operations are not supported at all;
4393 - there are some problems with boolean types;
4395 - Pascal type hexadecimal constants are not supported
4396 because they conflict with the internal variables format;
4398 - support for Pascal objects and classes is not full yet;
4400 - unlike Pascal, GDB is case-sensitive for symbol names.
4402 * Changes in completion.
4404 Commands such as `shell', `run' and `set args', which pass arguments
4405 to inferior programs, now complete on file names, similar to what
4406 users expect at the shell prompt.
4408 Commands which accept locations, such as `disassemble', `print',
4409 `breakpoint', `until', etc. now complete on filenames as well as
4410 program symbols. Thus, if you type "break foob TAB", and the source
4411 files linked into the programs include `foobar.c', that file name will
4412 be one of the candidates for completion. However, file names are not
4413 considered for completion after you typed a colon that delimits a file
4414 name from a name of a function in that file, as in "break foo.c:bar".
4416 `set demangle-style' completes on available demangling styles.
4418 * New platform-independent commands:
4420 It is now possible to define a post-hook for a command as well as a
4421 hook that runs before the command. For more details, see the
4422 documentation of `hookpost' in the GDB manual.
4424 * Changes in GNU/Linux native debugging.
4426 Support for debugging multi-threaded programs has been completely
4427 revised for all platforms except m68k and sparc. You can now debug as
4428 many threads as your system allows you to have.
4430 Attach/detach is supported for multi-threaded programs.
4432 Support for SSE registers was added for x86. This doesn't work for
4433 multi-threaded programs though.
4435 * Changes in MIPS configurations.
4437 Multi-arch support is enabled for all MIPS configurations.
4439 GDB can now be built as native debugger on SGI Irix 6.x systems for
4440 debugging n32 executables. (Debugging 64-bit executables is not yet
4443 * Unified support for hardware watchpoints in all x86 configurations.
4445 Most (if not all) native x86 configurations support hardware-assisted
4446 breakpoints and watchpoints in a unified manner. This support
4447 implements debug register sharing between watchpoints, which allows to
4448 put a virtually infinite number of watchpoints on the same address,
4449 and also supports watching regions up to 16 bytes with several debug
4452 The new maintenance command `maintenance show-debug-regs' toggles
4453 debugging print-outs in functions that insert, remove, and test
4454 watchpoints and hardware breakpoints.
4456 * Changes in the DJGPP native configuration.
4458 New command ``info dos sysinfo'' displays assorted information about
4459 the CPU, OS, memory, and DPMI server.
4461 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4462 display information about segment descriptors stored in GDT, LDT, and
4465 New commands ``info dos pde'' and ``info dos pte'' display entries
4466 from Page Directory and Page Tables (for now works with CWSDPMI only).
4467 New command ``info dos address-pte'' displays the Page Table entry for
4468 a given linear address.
4470 GDB can now pass command lines longer than 126 characters to the
4471 program being debugged (requires an update to the libdbg.a library
4472 which is part of the DJGPP development kit).
4474 DWARF2 debug info is now supported.
4476 It is now possible to `step' and `next' through calls to `longjmp'.
4478 * Changes in documentation.
4480 All GDB documentation was converted to GFDL, the GNU Free
4481 Documentation License.
4483 Tracepoints-related commands are now fully documented in the GDB
4486 TUI, the Text-mode User Interface, is now documented in the manual.
4488 Tracepoints-related commands are now fully documented in the GDB
4491 The "GDB Internals" manual now has an index. It also includes
4492 documentation of `ui_out' functions, GDB coding standards, x86
4493 hardware watchpoints, and memory region attributes.
4495 * GDB's version number moved to ``version.in''
4497 The Makefile variable VERSION has been replaced by the file
4498 ``version.in''. People creating GDB distributions should update the
4499 contents of this file.
4503 GUD support is now a standard part of the EMACS distribution.
4505 *** Changes in GDB 5.0:
4507 * Improved support for debugging FP programs on x86 targets
4509 Unified and much-improved support for debugging floating-point
4510 programs on all x86 targets. In particular, ``info float'' now
4511 displays the FP registers in the same format on all x86 targets, with
4512 greater level of detail.
4514 * Improvements and bugfixes in hardware-assisted watchpoints
4516 It is now possible to watch array elements, struct members, and
4517 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4518 on x86 targets no longer erroneously trigger when the address is
4521 * Improvements in the native DJGPP version of GDB
4523 The distribution now includes all the scripts and auxiliary files
4524 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4525 machines ``out of the box''.
4527 The DJGPP version can now debug programs that use signals. It is
4528 possible to catch signals that happened in the debuggee, deliver
4529 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4530 would kill the program being debugged.) Programs that hook hardware
4531 interrupts (keyboard, timer, etc.) can also be debugged.
4533 It is now possible to debug DJGPP programs that redirect their
4534 standard handles or switch them to raw (as opposed to cooked) mode, or
4535 even close them. The command ``run < foo > bar'' works as expected,
4536 and ``info terminal'' reports useful information about the debuggee's
4537 terminal, including raw/cooked mode, redirection, etc.
4539 The DJGPP version now uses termios functions for console I/O, which
4540 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4543 DOS-style file names with drive letters are now fully supported by
4546 It is now possible to debug DJGPP programs that switch their working
4547 directory. It is also possible to rerun the debuggee any number of
4548 times without restarting GDB; thus, you can use the same setup,
4549 breakpoints, etc. for many debugging sessions.
4551 * New native configurations
4553 ARM GNU/Linux arm*-*-linux*
4554 PowerPC GNU/Linux powerpc-*-linux*
4558 Motorola MCore mcore-*-*
4559 x86 VxWorks i[3456]86-*-vxworks*
4560 PowerPC VxWorks powerpc-*-vxworks*
4561 TI TMS320C80 tic80-*-*
4563 * OBSOLETE configurations
4565 Altos 3068 m68*-altos-*
4566 Convex c1-*-*, c2-*-*
4568 ARM RISCix arm-*-* (as host)
4571 Configurations that have been declared obsolete will be commented out,
4572 but the code will be left in place. If there is no activity to revive
4573 these configurations before the next release of GDB, the sources will
4574 be permanently REMOVED.
4576 * Gould support removed
4578 Support for the Gould PowerNode and NP1 has been removed.
4580 * New features for SVR4
4582 On SVR4 native platforms (such as Solaris), if you attach to a process
4583 without first loading a symbol file, GDB will now attempt to locate and
4584 load symbols from the running process's executable file.
4586 * Many C++ enhancements
4588 C++ support has been greatly improved. Overload resolution now works properly
4589 in almost all cases. RTTI support is on the way.
4591 * Remote targets can connect to a sub-program
4593 A popen(3) style serial-device has been added. This device starts a
4594 sub-process (such as a stand-alone simulator) and then communicates
4595 with that. The sub-program to run is specified using the syntax
4596 ``|<program> <args>'' vis:
4598 (gdb) set remotedebug 1
4599 (gdb) target extended-remote |mn10300-elf-sim program-args
4601 * MIPS 64 remote protocol
4603 A long standing bug in the mips64 remote protocol where by GDB
4604 expected certain 32 bit registers (ex SR) to be transfered as 32
4605 instead of 64 bits has been fixed.
4607 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4608 added to provide backward compatibility with older versions of GDB.
4610 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4612 The command ``set remotebinarydownload'' command has been replaced by
4613 ``set remote X-packet''. Other commands in ``set remote'' family
4614 include ``set remote P-packet''.
4616 * Breakpoint commands accept ranges.
4618 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4619 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4620 ``tracepoint passcount'' also accepts a range of tracepoints.
4622 * ``apropos'' command added.
4624 The ``apropos'' command searches through command names and
4625 documentation strings, printing out matches, making it much easier to
4626 try to find a command that does what you are looking for.
4630 A new machine oriented interface (MI) has been added to GDB. This
4631 interface is designed for debug environments running GDB as a separate
4632 process. This is part of the long term libGDB project. See the
4633 "GDB/MI" chapter of the GDB manual for further information. It can be
4634 enabled by configuring with:
4636 .../configure --enable-gdbmi
4638 *** Changes in GDB-4.18:
4640 * New native configurations
4642 HP-UX 10.20 hppa*-*-hpux10.20
4643 HP-UX 11.x hppa*-*-hpux11.0*
4644 M68K GNU/Linux m68*-*-linux*
4648 Fujitsu FR30 fr30-*-elf*
4649 Intel StrongARM strongarm-*-*
4650 Mitsubishi D30V d30v-*-*
4652 * OBSOLETE configurations
4654 Gould PowerNode, NP1 np1-*-*, pn-*-*
4656 Configurations that have been declared obsolete will be commented out,
4657 but the code will be left in place. If there is no activity to revive
4658 these configurations before the next release of GDB, the sources will
4659 be permanently REMOVED.
4663 As a compatibility experiment, GDB's source files buildsym.h and
4664 buildsym.c have been converted to pure standard C, no longer
4665 containing any K&R compatibility code. We believe that all systems in
4666 use today either come with a standard C compiler, or have a GCC port
4667 available. If this is not true, please report the affected
4668 configuration to bug-gdb@gnu.org immediately. See the README file for
4669 information about getting a standard C compiler if you don't have one
4674 GDB now uses readline 2.2.
4676 * set extension-language
4678 You can now control the mapping between filename extensions and source
4679 languages by using the `set extension-language' command. For instance,
4680 you can ask GDB to treat .c files as C++ by saying
4681 set extension-language .c c++
4682 The command `info extensions' lists all of the recognized extensions
4683 and their associated languages.
4685 * Setting processor type for PowerPC and RS/6000
4687 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4688 you can use the `set processor' command to specify what variant of the
4689 PowerPC family you are debugging. The command
4693 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4694 following PowerPC and RS6000 variants:
4696 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4697 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4699 403GC IBM PowerPC 403GC
4700 505 Motorola PowerPC 505
4701 860 Motorola PowerPC 860 or 850
4702 601 Motorola PowerPC 601
4703 602 Motorola PowerPC 602
4704 603 Motorola/IBM PowerPC 603 or 603e
4705 604 Motorola PowerPC 604 or 604e
4706 750 Motorola/IBM PowerPC 750 or 750
4708 At the moment, this command just tells GDB what to name the
4709 special-purpose processor registers. Since almost all the affected
4710 registers are inaccessible to user-level programs, this command is
4711 only useful for remote debugging in its present form.
4715 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4716 more extensive support for HP-UX. Added features include shared
4717 library support, kernel threads and hardware watchpoints for 11.00,
4718 support for HP's ANSI C and C++ compilers, and a compatibility mode
4719 for xdb and dbx commands.
4723 HP's donation includes the new concept of catchpoints, which is a
4724 generalization of the old catch command. On HP-UX, it is now possible
4725 to catch exec, fork, and vfork, as well as library loading.
4727 This means that the existing catch command has changed; its first
4728 argument now specifies the type of catch to be set up. See the
4729 output of "help catch" for a list of catchpoint types.
4731 * Debugging across forks
4733 On HP-UX, you can choose which process to debug when a fork() happens
4738 HP has donated a curses-based terminal user interface (TUI). To get
4739 it, build with --enable-tui. Although this can be enabled for any
4740 configuration, at present it only works for native HP debugging.
4742 * GDB remote protocol additions
4744 A new protocol packet 'X' that writes binary data is now available.
4745 Default behavior is to try 'X', then drop back to 'M' if the stub
4746 fails to respond. The settable variable `remotebinarydownload'
4747 allows explicit control over the use of 'X'.
4749 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4750 full 64-bit address. The command
4752 set remoteaddresssize 32
4754 can be used to revert to the old behaviour. For existing remote stubs
4755 the change should not be noticed, as the additional address information
4758 In order to assist in debugging stubs, you may use the maintenance
4759 command `packet' to send any text string to the stub. For instance,
4761 maint packet heythere
4763 sends the packet "$heythere#<checksum>". Note that it is very easy to
4764 disrupt a debugging session by sending the wrong packet at the wrong
4767 The compare-sections command allows you to compare section data on the
4768 target to what is in the executable file without uploading or
4769 downloading, by comparing CRC checksums.
4771 * Tracing can collect general expressions
4773 You may now collect general expressions at tracepoints. This requires
4774 further additions to the target-side stub; see tracepoint.c and
4775 doc/agentexpr.texi for further details.
4777 * mask-address variable for Mips
4779 For Mips targets, you may control the zeroing of the upper 32 bits of
4780 a 64-bit address by entering `set mask-address on'. This is mainly
4781 of interest to users of embedded R4xxx and R5xxx processors.
4783 * Higher serial baud rates
4785 GDB's serial code now allows you to specify baud rates 57600, 115200,
4786 230400, and 460800 baud. (Note that your host system may not be able
4787 to achieve all of these rates.)
4791 The i960 configuration now includes an initial implementation of a
4792 builtin simulator, contributed by Jim Wilson.
4795 *** Changes in GDB-4.17:
4797 * New native configurations
4799 Alpha GNU/Linux alpha*-*-linux*
4800 Unixware 2.x i[3456]86-unixware2*
4801 Irix 6.x mips*-sgi-irix6*
4802 PowerPC GNU/Linux powerpc-*-linux*
4803 PowerPC Solaris powerpcle-*-solaris*
4804 Sparc GNU/Linux sparc-*-linux*
4805 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4809 Argonaut Risc Chip (ARC) arc-*-*
4810 Hitachi H8/300S h8300*-*-*
4811 Matsushita MN10200 w/simulator mn10200-*-*
4812 Matsushita MN10300 w/simulator mn10300-*-*
4813 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4814 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4815 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4816 Mitsubishi D10V w/simulator d10v-*-*
4817 Mitsubishi M32R/D w/simulator m32r-*-elf*
4818 Tsqware Sparclet sparclet-*-*
4819 NEC V850 w/simulator v850-*-*
4821 * New debugging protocols
4823 ARM with RDI protocol arm*-*-*
4824 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4825 DDB and LSI variants of PMON protocol mips*-*-*
4826 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4827 PowerPC with SDS protocol powerpc{,le}-*-eabi
4828 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4832 All configurations can now understand and use the DWARF 2 debugging
4833 format. The choice is automatic, if the symbol file contains DWARF 2
4838 GDB now includes basic Java language support. This support is
4839 only useful with Java compilers that produce native machine code.
4841 * solib-absolute-prefix and solib-search-path
4843 For SunOS and SVR4 shared libraries, you may now set the prefix for
4844 loading absolute shared library symbol files, and the search path for
4845 locating non-absolute shared library symbol files.
4847 * Live range splitting
4849 GDB can now effectively debug code for which GCC has performed live
4850 range splitting as part of its optimization. See gdb/doc/LRS for
4851 more details on the expected format of the stabs information.
4855 GDB's support for the GNU Hurd, including thread debugging, has been
4856 updated to work with current versions of the Hurd.
4860 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4861 instruction set. ARM GDB automatically detects when Thumb
4862 instructions are in use, and adjusts disassembly and backtracing
4867 GDB's MIPS target configurations now handle the MIP16 16-bit
4872 GDB now includes support for overlays; if an executable has been
4873 linked such that multiple sections are based at the same address, GDB
4874 will decide which section to use for symbolic info. You can choose to
4875 control the decision manually, using overlay commands, or implement
4876 additional target-side support and use "overlay load-target" to bring
4877 in the overlay mapping. Do "help overlay" for more detail.
4881 The command "info symbol <address>" displays information about
4882 the symbol at the specified address.
4886 The standard remote protocol now includes an extension that allows
4887 asynchronous collection and display of trace data. This requires
4888 extensive support in the target-side debugging stub. Tracing mode
4889 includes a new interaction mode in GDB and new commands: see the
4890 file tracepoint.c for more details.
4894 Configurations for embedded MIPS now include a simulator contributed
4895 by Cygnus Solutions. The simulator supports the instruction sets
4896 of most MIPS variants.
4900 Sparc configurations may now include the ERC32 simulator contributed
4901 by the European Space Agency. The simulator is not built into
4902 Sparc targets by default; configure with --enable-sim to include it.
4906 For target configurations that may include multiple variants of a
4907 basic architecture (such as MIPS and SH), you may now set the
4908 architecture explicitly. "set arch" sets, "info arch" lists
4909 the possible architectures.
4911 *** Changes in GDB-4.16:
4913 * New native configurations
4915 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4916 M68K NetBSD m68k-*-netbsd*
4917 PowerPC AIX 4.x powerpc-*-aix*
4918 PowerPC MacOS powerpc-*-macos*
4919 PowerPC Windows NT powerpcle-*-cygwin32
4920 RS/6000 AIX 4.x rs6000-*-aix4*
4924 ARM with RDP protocol arm-*-*
4925 I960 with MON960 i960-*-coff
4926 MIPS VxWorks mips*-*-vxworks*
4927 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4928 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4930 Matra Sparclet sparclet-*-*
4934 The powerpc-eabi configuration now includes the PSIM simulator,
4935 contributed by Andrew Cagney, with assistance from Mike Meissner.
4936 PSIM is a very elaborate model of the PowerPC, including not only
4937 basic instruction set execution, but also details of execution unit
4938 performance and I/O hardware. See sim/ppc/README for more details.
4942 GDB now works with Solaris 2.5.
4944 * Windows 95/NT native
4946 GDB will now work as a native debugger on Windows 95 and Windows NT.
4947 To build it from source, you must use the "gnu-win32" environment,
4948 which uses a DLL to emulate enough of Unix to run the GNU tools.
4949 Further information, binaries, and sources are available at
4950 ftp.cygnus.com, under pub/gnu-win32.
4952 * dont-repeat command
4954 If a user-defined command includes the command `dont-repeat', then the
4955 command will not be repeated if the user just types return. This is
4956 useful if the command is time-consuming to run, so that accidental
4957 extra keystrokes don't run the same command many times.
4959 * Send break instead of ^C
4961 The standard remote protocol now includes an option to send a break
4962 rather than a ^C to the target in order to interrupt it. By default,
4963 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4965 * Remote protocol timeout
4967 The standard remote protocol includes a new variable `remotetimeout'
4968 that allows you to set the number of seconds before GDB gives up trying
4969 to read from the target. The default value is 2.
4971 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4973 By default GDB will automatically keep track of objects as they are
4974 loaded and unloaded by the dynamic linker. By using the command `set
4975 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4976 when shared library events occur, thus allowing you to set breakpoints
4977 in shared libraries which are explicitly loaded by the inferior.
4979 Note this feature does not work on hpux8. On hpux9 you must link
4980 /usr/lib/end.o into your program. This feature should work
4981 automatically on hpux10.
4983 * Irix 5.x hardware watchpoint support
4985 Irix 5 configurations now support the use of hardware watchpoints.
4987 * Mips protocol "SYN garbage limit"
4989 When debugging a Mips target using the `target mips' protocol, you
4990 may set the number of characters that GDB will ignore by setting
4991 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4992 every character. The default value is 1050.
4994 * Recording and replaying remote debug sessions
4996 If you set `remotelogfile' to the name of a file, gdb will write to it
4997 a recording of a remote debug session. This recording may then be
4998 replayed back to gdb using "gdbreplay". See gdbserver/README for
4999 details. This is useful when you have a problem with GDB while doing
5000 remote debugging; you can make a recording of the session and send it
5001 to someone else, who can then recreate the problem.
5003 * Speedups for remote debugging
5005 GDB includes speedups for downloading and stepping MIPS systems using
5006 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5007 and more efficient S-record downloading.
5009 * Memory use reductions and statistics collection
5011 GDB now uses less memory and reports statistics about memory usage.
5012 Try the `maint print statistics' command, for example.
5014 *** Changes in GDB-4.15:
5016 * Psymtabs for XCOFF
5018 The symbol reader for AIX GDB now uses partial symbol tables. This
5019 can greatly improve startup time, especially for large executables.
5021 * Remote targets use caching
5023 Remote targets now use a data cache to speed up communication with the
5024 remote side. The data cache could lead to incorrect results because
5025 it doesn't know about volatile variables, thus making it impossible to
5026 debug targets which use memory mapped I/O devices. `set remotecache
5027 off' turns the the data cache off.
5029 * Remote targets may have threads
5031 The standard remote protocol now includes support for multiple threads
5032 in the target system, using new protocol commands 'H' and 'T'. See
5033 gdb/remote.c for details.
5037 If GDB is configured with `--enable-netrom', then it will include
5038 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5039 acts as though it is a bank of ROM on the target board, but you can
5040 write into it over the network. GDB's support consists only of
5041 support for fast loading into the emulated ROM; to debug, you must use
5042 another protocol, such as standard remote protocol. The usual
5043 sequence is something like
5045 target nrom <netrom-hostname>
5047 target remote <netrom-hostname>:1235
5051 GDB now includes support for the Apple Macintosh, as a host only. It
5052 may be run as either an MPW tool or as a standalone application, and
5053 it can debug through the serial port. All the usual GDB commands are
5054 available, but to the target command, you must supply "serial" as the
5055 device type instead of "/dev/ttyXX". See mpw-README in the main
5056 directory for more information on how to build. The MPW configuration
5057 scripts */mpw-config.in support only a few targets, and only the
5058 mips-idt-ecoff target has been tested.
5062 GDB configuration now uses autoconf. This is not user-visible,
5063 but does simplify configuration and building.
5067 GDB now supports hpux10.
5069 *** Changes in GDB-4.14:
5071 * New native configurations
5073 x86 FreeBSD i[345]86-*-freebsd
5074 x86 NetBSD i[345]86-*-netbsd
5075 NS32k NetBSD ns32k-*-netbsd
5076 Sparc NetBSD sparc-*-netbsd
5080 A29K VxWorks a29k-*-vxworks
5081 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5082 CPU32 EST-300 emulator m68*-*-est*
5083 PowerPC ELF powerpc-*-elf
5086 * Alpha OSF/1 support for procfs
5088 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5089 possible to attach to running processes. As the mounting of the /proc
5090 filesystem is optional on the Alpha, GDB automatically determines
5091 the availability of /proc during startup. This can lead to problems
5092 if /proc is unmounted after GDB has been started.
5094 * Arguments to user-defined commands
5096 User commands may accept up to 10 arguments separated by whitespace.
5097 Arguments are accessed within the user command via $arg0..$arg9. A
5100 print $arg0 + $arg1 + $arg2
5102 To execute the command use:
5105 Defines the command "adder" which prints the sum of its three arguments.
5106 Note the arguments are text substitutions, so they may reference variables,
5107 use complex expressions, or even perform inferior function calls.
5109 * New `if' and `while' commands
5111 This makes it possible to write more sophisticated user-defined
5112 commands. Both commands take a single argument, which is the
5113 expression to evaluate, and must be followed by the commands to
5114 execute, one per line, if the expression is nonzero, the list being
5115 terminated by the word `end'. The `if' command list may include an
5116 `else' word, which causes the following commands to be executed only
5117 if the expression is zero.
5119 * Fortran source language mode
5121 GDB now includes partial support for Fortran 77. It will recognize
5122 Fortran programs and can evaluate a subset of Fortran expressions, but
5123 variables and functions may not be handled correctly. GDB will work
5124 with G77, but does not yet know much about symbols emitted by other
5127 * Better HPUX support
5129 Most debugging facilities now work on dynamic executables for HPPAs
5130 running hpux9 or later. You can attach to running dynamically linked
5131 processes, but by default the dynamic libraries will be read-only, so
5132 for instance you won't be able to put breakpoints in them. To change
5133 that behavior do the following before running the program:
5139 This will cause the libraries to be mapped private and read-write.
5140 To revert to the normal behavior, do this:
5146 You cannot set breakpoints or examine data in the library until after
5147 the library is loaded if the function/data symbols do not have
5150 GDB can now also read debug symbols produced by the HP C compiler on
5151 HPPAs (sorry, no C++, Fortran or 68k support).
5153 * Target byte order now dynamically selectable
5155 You can choose which byte order to use with a target system, via the
5156 commands "set endian big" and "set endian little", and you can see the
5157 current setting by using "show endian". You can also give the command
5158 "set endian auto", in which case GDB will use the byte order
5159 associated with the executable. Currently, only embedded MIPS
5160 configurations support dynamic selection of target byte order.
5162 * New DOS host serial code
5164 This version uses DPMI interrupts to handle buffered I/O, so you
5165 no longer need to run asynctsr when debugging boards connected to
5168 *** Changes in GDB-4.13:
5170 * New "complete" command
5172 This lists all the possible completions for the rest of the line, if it
5173 were to be given as a command itself. This is intended for use by emacs.
5175 * Trailing space optional in prompt
5177 "set prompt" no longer adds a space for you after the prompt you set. This
5178 allows you to set a prompt which ends in a space or one that does not.
5180 * Breakpoint hit counts
5182 "info break" now displays a count of the number of times the breakpoint
5183 has been hit. This is especially useful in conjunction with "ignore"; you
5184 can ignore a large number of breakpoint hits, look at the breakpoint info
5185 to see how many times the breakpoint was hit, then run again, ignoring one
5186 less than that number, and this will get you quickly to the last hit of
5189 * Ability to stop printing at NULL character
5191 "set print null-stop" will cause GDB to stop printing the characters of
5192 an array when the first NULL is encountered. This is useful when large
5193 arrays actually contain only short strings.
5195 * Shared library breakpoints
5197 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5198 breakpoints in shared libraries before the executable is run.
5200 * Hardware watchpoints
5202 There is a new hardware breakpoint for the watch command for sparclite
5203 targets. See gdb/sparclite/hw_breakpoint.note.
5205 Hardware watchpoints are also now supported under GNU/Linux.
5209 Annotations have been added. These are for use with graphical interfaces,
5210 and are still experimental. Currently only gdba.el uses these.
5212 * Improved Irix 5 support
5214 GDB now works properly with Irix 5.2.
5216 * Improved HPPA support
5218 GDB now works properly with the latest GCC and GAS.
5220 * New native configurations
5222 Sequent PTX4 i[34]86-sequent-ptx4
5223 HPPA running OSF/1 hppa*-*-osf*
5224 Atari TT running SVR4 m68*-*-sysv4*
5225 RS/6000 LynxOS rs6000-*-lynxos*
5229 OS/9000 i[34]86-*-os9k
5230 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5233 * Hitachi SH7000 and E7000-PC ICE support
5235 There is now support for communicating with the Hitachi E7000-PC ICE.
5236 This is available automatically when GDB is configured for the SH.
5240 As usual, a variety of small fixes and improvements, both generic
5241 and configuration-specific. See the ChangeLog for more detail.
5243 *** Changes in GDB-4.12:
5245 * Irix 5 is now supported
5249 GDB-4.12 on the HPPA has a number of changes which make it unable
5250 to debug the output from the currently released versions of GCC and
5251 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5252 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5253 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5256 *** Changes in GDB-4.11:
5258 * User visible changes:
5262 The "set remotedebug" option is now consistent between the mips remote
5263 target, remote targets using the gdb-specific protocol, UDI (AMD's
5264 debug protocol for the 29k) and the 88k bug monitor. It is now an
5265 integer specifying a debug level (normally 0 or 1, but 2 means more
5266 debugging info for the mips target).
5268 * DEC Alpha native support
5270 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5271 debug info, but GDB works fairly well with the DEC compiler and should
5272 work with a future GCC release. See the README file for a few
5273 Alpha-specific notes.
5275 * Preliminary thread implementation
5277 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5279 * LynxOS native and target support for 386
5281 This release has been hosted on LynxOS 2.2, and also can be configured
5282 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5285 * Improvements in C++ mangling/demangling.
5287 This release has much better g++ debugging, specifically in name
5288 mangling/demangling, virtual function calls, print virtual table,
5289 call methods, ...etc.
5291 *** Changes in GDB-4.10:
5293 * User visible changes:
5295 Remote debugging using the GDB-specific (`target remote') protocol now
5296 supports the `load' command. This is only useful if you have some
5297 other way of getting the stub to the target system, and you can put it
5298 somewhere in memory where it won't get clobbered by the download.
5300 Filename completion now works.
5302 When run under emacs mode, the "info line" command now causes the
5303 arrow to point to the line specified. Also, "info line" prints
5304 addresses in symbolic form (as well as hex).
5306 All vxworks based targets now support a user settable option, called
5307 vxworks-timeout. This option represents the number of seconds gdb
5308 should wait for responses to rpc's. You might want to use this if
5309 your vxworks target is, perhaps, a slow software simulator or happens
5310 to be on the far side of a thin network line.
5314 This release contains support for using a DEC alpha as a GDB host for
5315 cross debugging. Native alpha debugging is not supported yet.
5318 *** Changes in GDB-4.9:
5322 This is the first GDB release which is accompanied by a matching testsuite.
5323 The testsuite requires installation of dejagnu, which should be available
5324 via ftp from most sites that carry GNU software.
5328 'Cfront' style demangling has had its name changed to 'ARM' style, to
5329 emphasize that it was written from the specifications in the C++ Annotated
5330 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5331 disclaimers, it still generated too much confusion with users attempting to
5332 use gdb with AT&T cfront.
5336 GDB now uses a standard remote interface to a simulator library.
5337 So far, the library contains simulators for the Zilog Z8001/2, the
5338 Hitachi H8/300, H8/500 and Super-H.
5340 * New targets supported
5342 H8/300 simulator h8300-hitachi-hms or h8300hms
5343 H8/500 simulator h8500-hitachi-hms or h8500hms
5344 SH simulator sh-hitachi-hms or sh
5345 Z8000 simulator z8k-zilog-none or z8ksim
5346 IDT MIPS board over serial line mips-idt-ecoff
5348 Cross-debugging to GO32 targets is supported. It requires a custom
5349 version of the i386-stub.c module which is integrated with the
5350 GO32 memory extender.
5352 * New remote protocols
5354 MIPS remote debugging protocol.
5356 * New source languages supported
5358 This version includes preliminary support for Chill, a Pascal like language
5359 used by telecommunications companies. Chill support is also being integrated
5360 into the GNU compiler, but we don't know when it will be publically available.
5363 *** Changes in GDB-4.8:
5365 * HP Precision Architecture supported
5367 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5368 version of this support was available as a set of patches from the
5369 University of Utah. GDB does not support debugging of programs
5370 compiled with the HP compiler, because HP will not document their file
5371 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5372 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5374 Many problems in the preliminary version have been fixed.
5376 * Faster and better demangling
5378 We have improved template demangling and fixed numerous bugs in the GNU style
5379 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5380 character types (wchar_t) are now supported. Demangling of each symbol is now
5381 only done once, and is cached when the symbol table for a file is read in.
5382 This results in a small increase in memory usage for C programs, a moderate
5383 increase in memory usage for C++ programs, and a fantastic speedup in
5386 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5387 from the specifications in the Annotated Reference Manual, which AT&T's
5388 compiler does not actually implement.
5390 * G++ multiple inheritance compiler problem
5392 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5393 inheritance lattices was reworked to properly discover ambiguities. We
5394 recently found an example which causes this new algorithm to fail in a
5395 very subtle way, producing bad debug information for those classes.
5396 The file 'gcc.patch' (in this directory) can be applied to gcc to
5397 circumvent the problem. A future GCC release will contain a complete
5400 The previous G++ debug info problem (mentioned below for the gdb-4.7
5401 release) is fixed in gcc version 2.3.2.
5403 * Improved configure script
5405 The `configure' script will now attempt to guess your system type if
5406 you don't supply a host system type. The old scheme of supplying a
5407 host system triplet is preferable over using this. All the magic is
5408 done in the new `config.guess' script. Examine it for details.
5410 We have also brought our configure script much more in line with the FSF's
5411 version. It now supports the --with-xxx options. In particular,
5412 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5413 The resulting GDB will not be able to read arbitrary object file formats --
5414 only the format ``expected'' to be used on the configured target system.
5415 We hope to make this the default in a future release.
5417 * Documentation improvements
5419 There's new internal documentation on how to modify GDB, and how to
5420 produce clean changes to the code. We implore people to read it
5421 before submitting changes.
5423 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5424 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5425 `info' files are also provided. To build `info' files from scratch,
5426 you will need the latest `makeinfo' release, which will be available in
5427 a future texinfo-X.Y release.
5429 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5430 We're not sure exactly which versions have this problem, but it has
5431 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5432 or better. If that isn't possible, there is a patch in
5433 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5434 around this problem.
5438 GDB now supports array constants that can be used in expressions typed in by
5439 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5440 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5443 The new directory `gdb/sparclite' contains a program that demonstrates
5444 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5446 * New native hosts supported
5448 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5449 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5451 * New targets supported
5453 AMD 29k family via UDI a29k-amd-udi or udi29k
5455 * New file formats supported
5457 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5458 HPUX core files, and SCO 3.2v2 core files.
5462 Attaching to processes now works again; thanks for the many bug reports.
5464 We have also stomped on a bunch of core dumps caused by
5465 printf_filtered("%s") problems.
5467 We eliminated a copyright problem on the rpc and ptrace header files
5468 for VxWorks, which was discovered at the last minute during the 4.7
5469 release. You should now be able to build a VxWorks GDB.
5471 You can now interrupt gdb while an attached process is running. This
5472 will cause the attached process to stop, and give control back to GDB.
5474 We fixed problems caused by using too many file descriptors
5475 for reading symbols from object files and libraries. This was
5476 especially a problem for programs that used many (~100) shared
5479 The `step' command now only enters a subroutine if there is line number
5480 information for the subroutine. Otherwise it acts like the `next'
5481 command. Previously, `step' would enter subroutines if there was
5482 any debugging information about the routine. This avoids problems
5483 when using `cc -g1' on MIPS machines.
5485 * Internal improvements
5487 GDB's internal interfaces have been improved to make it easier to support
5488 debugging of multiple languages in the future.
5490 GDB now uses a common structure for symbol information internally.
5491 Minimal symbols (derived from linkage symbols in object files), partial
5492 symbols (from a quick scan of debug information), and full symbols
5493 contain a common subset of information, making it easier to write
5494 shared code that handles any of them.
5496 * New command line options
5498 We now accept --silent as an alias for --quiet.
5502 The memory-mapped-malloc library is now licensed under the GNU Library
5503 General Public License.
5505 *** Changes in GDB-4.7:
5507 * Host/native/target split
5509 GDB has had some major internal surgery to untangle the support for
5510 hosts and remote targets. Now, when you configure GDB for a remote
5511 target, it will no longer load in all of the support for debugging
5512 local programs on the host. When fully completed and tested, this will
5513 ensure that arbitrary host/target combinations are possible.
5515 The primary conceptual shift is to separate the non-portable code in
5516 GDB into three categories. Host specific code is required any time GDB
5517 is compiled on that host, regardless of the target. Target specific
5518 code relates to the peculiarities of the target, but can be compiled on
5519 any host. Native specific code is everything else: it can only be
5520 built when the host and target are the same system. Child process
5521 handling and core file support are two common `native' examples.
5523 GDB's use of /proc for controlling Unix child processes is now cleaner.
5524 It has been split out into a single module under the `target_ops' vector,
5525 plus two native-dependent functions for each system that uses /proc.
5527 * New hosts supported
5529 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5530 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5531 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5533 * New targets supported
5535 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5536 68030 and CPU32 m68030-*-*, m68332-*-*
5538 * New native hosts supported
5540 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5541 (386bsd is not well tested yet)
5542 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5544 * New file formats supported
5546 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5547 supports reading of `a.out.adobe' object files, which are an a.out
5548 format extended with minimal information about multiple sections.
5552 `show copying' is the same as the old `info copying'.
5553 `show warranty' is the same as `info warrantee'.
5554 These were renamed for consistency. The old commands continue to work.
5556 `info handle' is a new alias for `info signals'.
5558 You can now define pre-command hooks, which attach arbitrary command
5559 scripts to any command. The commands in the hook will be executed
5560 prior to the user's command. You can also create a hook which will be
5561 executed whenever the program stops. See gdb.texinfo.
5565 We now deal with Cfront style name mangling, and can even extract type
5566 info from mangled symbols. GDB can automatically figure out which
5567 symbol mangling style your C++ compiler uses.
5569 Calling of methods and virtual functions has been improved as well.
5573 The crash that occured when debugging Sun Ansi-C compiled binaries is
5574 fixed. This was due to mishandling of the extra N_SO stabs output
5577 We also finally got Ultrix 4.2 running in house, and fixed core file
5578 support, with help from a dozen people on the net.
5580 John M. Farrell discovered that the reason that single-stepping was so
5581 slow on all of the Mips based platforms (primarily SGI and DEC) was
5582 that we were trying to demangle and lookup a symbol used for internal
5583 purposes on every instruction that was being stepped through. Changing
5584 the name of that symbol so that it couldn't be mistaken for a C++
5585 mangled symbol sped things up a great deal.
5587 Rich Pixley sped up symbol lookups in general by getting much smarter
5588 about when C++ symbol mangling is necessary. This should make symbol
5589 completion (TAB on the command line) much faster. It's not as fast as
5590 we'd like, but it's significantly faster than gdb-4.6.
5594 A new user controllable variable 'call_scratch_address' can
5595 specify the location of a scratch area to be used when GDB
5596 calls a function in the target. This is necessary because the
5597 usual method of putting the scratch area on the stack does not work
5598 in systems that have separate instruction and data spaces.
5600 We integrated changes to support the 29k UDI (Universal Debugger
5601 Interface), but discovered at the last minute that we didn't have all
5602 of the appropriate copyright paperwork. We are working with AMD to
5603 resolve this, and hope to have it available soon.
5607 We have sped up the remote serial line protocol, especially for targets
5608 with lots of registers. It now supports a new `expedited status' ('T')
5609 message which can be used in place of the existing 'S' status message.
5610 This allows the remote stub to send only the registers that GDB
5611 needs to make a quick decision about single-stepping or conditional
5612 breakpoints, eliminating the need to fetch the entire register set for
5613 each instruction being stepped through.
5615 The GDB remote serial protocol now implements a write-through cache for
5616 registers, only re-reading the registers if the target has run.
5618 There is also a new remote serial stub for SPARC processors. You can
5619 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5620 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5621 processor with a serial port.
5625 Configure.in files have become much easier to read and modify. A new
5626 `table driven' format makes it more obvious what configurations are
5627 supported, and what files each one uses.
5631 There is a new opcodes library which will eventually contain all of the
5632 disassembly routines and opcode tables. At present, it only contains
5633 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5634 disassembler (binutils/objdump) to share these routines.
5636 The libiberty library is now copylefted under the GNU Library General
5637 Public License. This allows more liberal use, and was done so libg++
5638 can use it. This makes no difference to GDB, since the Library License
5639 grants all the rights from the General Public License.
5643 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5644 reference to the stabs symbol info used by the debugger. It is (as far
5645 as we know) the only published document on this fascinating topic. We
5646 encourage you to read it, compare it to the stabs information on your
5647 system, and send improvements on the document in general (to
5648 bug-gdb@prep.ai.mit.edu).
5650 And, of course, many bugs have been fixed.
5653 *** Changes in GDB-4.6:
5655 * Better support for C++ function names
5657 GDB now accepts as input the "demangled form" of C++ overloaded function
5658 names and member function names, and can do command completion on such names
5659 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5660 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5661 Make use of command completion, it is your friend.
5663 GDB also now accepts a variety of C++ mangled symbol formats. They are
5664 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5665 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5666 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5667 for the list of formats.
5669 * G++ symbol mangling problem
5671 Recent versions of gcc have a bug in how they emit debugging information for
5672 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5673 directory) can be applied to gcc to fix the problem. Alternatively, if you
5674 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5675 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5676 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5679 * New 'maintenance' command
5681 All of the commands related to hacking GDB internals have been moved out of
5682 the main command set, and now live behind the 'maintenance' command. This
5683 can also be abbreviated as 'mt'. The following changes were made:
5685 dump-me -> maintenance dump-me
5686 info all-breakpoints -> maintenance info breakpoints
5687 printmsyms -> maintenance print msyms
5688 printobjfiles -> maintenance print objfiles
5689 printpsyms -> maintenance print psymbols
5690 printsyms -> maintenance print symbols
5692 The following commands are new:
5694 maintenance demangle Call internal GDB demangler routine to
5695 demangle a C++ link name and prints the result.
5696 maintenance print type Print a type chain for a given symbol
5698 * Change to .gdbinit file processing
5700 We now read the $HOME/.gdbinit file before processing the argv arguments
5701 (e.g. reading symbol files or core files). This allows global parameters to
5702 be set, which will apply during the symbol reading. The ./.gdbinit is still
5703 read after argv processing.
5705 * New hosts supported
5707 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5709 GNU/Linux support i386-unknown-linux or linux
5711 We are also including code to support the HP/PA running BSD and HPUX. This
5712 is almost guaranteed not to work, as we didn't have time to test or build it
5713 for this release. We are including it so that the more adventurous (or
5714 masochistic) of you can play with it. We also had major problems with the
5715 fact that the compiler that we got from HP doesn't support the -g option.
5718 * New targets supported
5720 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5722 * More smarts about finding #include files
5724 GDB now remembers the compilation directory for all include files, and for
5725 all files from which C is generated (like yacc and lex sources). This
5726 greatly improves GDB's ability to find yacc/lex sources, and include files,
5727 especially if you are debugging your program from a directory different from
5728 the one that contains your sources.
5730 We also fixed a bug which caused difficulty with listing and setting
5731 breakpoints in include files which contain C code. (In the past, you had to
5732 try twice in order to list an include file that you hadn't looked at before.)
5734 * Interesting infernals change
5736 GDB now deals with arbitrary numbers of sections, where the symbols for each
5737 section must be relocated relative to that section's landing place in the
5738 target's address space. This work was needed to support ELF with embedded
5739 stabs used by Solaris-2.0.
5741 * Bug fixes (of course!)
5743 There have been loads of fixes for the following things:
5744 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5745 i960, stabs, DOS(GO32), procfs, etc...
5747 See the ChangeLog for details.
5749 *** Changes in GDB-4.5:
5751 * New machines supported (host and target)
5753 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5755 SGI Irix-4.x mips-sgi-irix4 or iris4
5757 * New malloc package
5759 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5760 Mmalloc is capable of handling mutiple heaps of memory. It is also
5761 capable of saving a heap to a file, and then mapping it back in later.
5762 This can be used to greatly speedup the startup of GDB by using a
5763 pre-parsed symbol table which lives in a mmalloc managed heap. For
5764 more details, please read mmalloc/mmalloc.texi.
5768 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5769 'help info proc' for details.
5771 * MIPS ecoff symbol table format
5773 The code that reads MIPS symbol table format is now supported on all hosts.
5774 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5777 * File name changes for MS-DOS
5779 Many files in the config directories have been renamed to make it easier to
5780 support GDB on MS-DOSe systems (which have very restrictive file name
5781 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5782 environment) is close to working but has some remaining problems. Note
5783 that debugging of DOS programs is not supported, due to limitations
5784 in the ``operating system'', but it can be used to host cross-debugging.
5786 * Cross byte order fixes
5788 Many fixes have been made to support cross debugging of Sparc and MIPS
5789 targets from hosts whose byte order differs.
5791 * New -mapped and -readnow options
5793 If memory-mapped files are available on your system through the 'mmap'
5794 system call, you can use the -mapped option on the `file' or
5795 `symbol-file' commands to cause GDB to write the symbols from your
5796 program into a reusable file. If the program you are debugging is
5797 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5798 Future GDB debugging sessions will notice the presence of this file,
5799 and will quickly map in symbol information from it, rather than reading
5800 the symbol table from the executable program. Using the '-mapped'
5801 option in a GDB `file' or `symbol-file' command has the same effect as
5802 starting GDB with the '-mapped' command-line option.
5804 You can cause GDB to read the entire symbol table immediately by using
5805 the '-readnow' option with any of the commands that load symbol table
5806 information (or on the GDB command line). This makes the command
5807 slower, but makes future operations faster.
5809 The -mapped and -readnow options are typically combined in order to
5810 build a `fred.syms' file that contains complete symbol information.
5811 A simple GDB invocation to do nothing but build a `.syms' file for future
5814 gdb -batch -nx -mapped -readnow programname
5816 The `.syms' file is specific to the host machine on which GDB is run.
5817 It holds an exact image of GDB's internal symbol table. It cannot be
5818 shared across multiple host platforms.
5820 * longjmp() handling
5822 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5823 siglongjmp() without losing control. This feature has not yet been ported to
5824 all systems. It currently works on many 386 platforms, all MIPS-based
5825 platforms (SGI, DECstation, etc), and Sun3/4.
5829 Preliminary work has been put in to support the new Solaris OS from Sun. At
5830 this time, it can control and debug processes, but it is not capable of
5835 As always, many many bug fixes. The major areas were with g++, and mipsread.
5836 People using the MIPS-based platforms should experience fewer mysterious
5837 crashes and trashed symbol tables.
5839 *** Changes in GDB-4.4:
5841 * New machines supported (host and target)
5843 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5845 BSD Reno on Vax vax-dec-bsd
5846 Ultrix on Vax vax-dec-ultrix
5848 * New machines supported (target)
5850 AMD 29000 embedded, using EBMON a29k-none-none
5854 GDB continues to improve its handling of C++. `References' work better.
5855 The demangler has also been improved, and now deals with symbols mangled as
5856 per the Annotated C++ Reference Guide.
5858 GDB also now handles `stabs' symbol information embedded in MIPS
5859 `ecoff' symbol tables. Since the ecoff format was not easily
5860 extensible to handle new languages such as C++, this appeared to be a
5861 good way to put C++ debugging info into MIPS binaries. This option
5862 will be supported in the GNU C compiler, version 2, when it is
5865 * New features for SVR4
5867 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5868 shared libraries. Debugging dynamically linked programs should present
5869 only minor differences from debugging statically linked programs.
5871 The `info proc' command will print out information about any process
5872 on an SVR4 system (including the one you are debugging). At the moment,
5873 it prints the address mappings of the process.
5875 If you bring up GDB on another SVR4 system, please send mail to
5876 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5878 * Better dynamic linking support in SunOS
5880 Reading symbols from shared libraries which contain debugging symbols
5881 now works properly. However, there remain issues such as automatic
5882 skipping of `transfer vector' code during function calls, which
5883 make it harder to debug code in a shared library, than to debug the
5884 same code linked statically.
5888 GDB is now using the latest `getopt' routines from the FSF. This
5889 version accepts the -- prefix for options with long names. GDB will
5890 continue to accept the old forms (-option and +option) as well.
5891 Various single letter abbreviations for options have been explicity
5892 added to the option table so that they won't get overshadowed in the
5893 future by other options that begin with the same letter.
5897 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5898 Many assorted bugs have been handled. Many more remain to be handled.
5899 See the various ChangeLog files (primarily in gdb and bfd) for details.
5902 *** Changes in GDB-4.3:
5904 * New machines supported (host and target)
5906 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5907 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5908 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5910 * Almost SCO Unix support
5912 We had hoped to support:
5913 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5914 (except for core file support), but we discovered very late in the release
5915 that it has problems with process groups that render gdb unusable. Sorry
5916 about that. I encourage people to fix it and post the fixes.
5918 * Preliminary ELF and DWARF support
5920 GDB can read ELF object files on System V Release 4, and can handle
5921 debugging records for C, in DWARF format, in ELF files. This support
5922 is preliminary. If you bring up GDB on another SVR4 system, please
5923 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5928 GDB now uses the latest `readline' library. One user-visible change
5929 is that two tabs will list possible command completions, which previously
5930 required typing M-? (meta-question mark, or ESC ?).
5934 The `stepi' bug that many of you noticed has been squashed.
5935 Many bugs in C++ have been handled. Many more remain to be handled.
5936 See the various ChangeLog files (primarily in gdb and bfd) for details.
5938 * State of the MIPS world (in case you wondered):
5940 GDB can understand the symbol tables emitted by the compilers
5941 supplied by most vendors of MIPS-based machines, including DEC. These
5942 symbol tables are in a format that essentially nobody else uses.
5944 Some versions of gcc come with an assembler post-processor called
5945 mips-tfile. This program is required if you want to do source-level
5946 debugging of gcc-compiled programs. I believe FSF does not ship
5947 mips-tfile with gcc version 1, but it will eventually come with gcc
5950 Debugging of g++ output remains a problem. g++ version 1.xx does not
5951 really support it at all. (If you're lucky, you should be able to get
5952 line numbers and stack traces to work, but no parameters or local
5953 variables.) With some work it should be possible to improve the
5956 When gcc version 2 is released, you will have somewhat better luck.
5957 However, even then you will get confusing results for inheritance and
5960 We will eventually provide full debugging of g++ output on
5961 DECstations. This will probably involve some kind of stabs-in-ecoff
5962 encapulation, but the details have not been worked out yet.
5965 *** Changes in GDB-4.2:
5967 * Improved configuration
5969 Only one copy of `configure' exists now, and it is not self-modifying.
5970 Porting BFD is simpler.
5974 The `step' and `next' commands now only stop at the first instruction
5975 of a source line. This prevents the multiple stops that used to occur
5976 in switch statements, for-loops, etc. `Step' continues to stop if a
5977 function that has debugging information is called within the line.
5981 Lots of small bugs fixed. More remain.
5983 * New host supported (not target)
5985 Intel 386 PC clone running Mach i386-none-mach
5988 *** Changes in GDB-4.1:
5990 * Multiple source language support
5992 GDB now has internal scaffolding to handle several source languages.
5993 It determines the type of each source file from its filename extension,
5994 and will switch expression parsing and number formatting to match the
5995 language of the function in the currently selected stack frame.
5996 You can also specifically set the language to be used, with
5997 `set language c' or `set language modula-2'.
6001 GDB now has preliminary support for the GNU Modula-2 compiler,
6002 currently under development at the State University of New York at
6003 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6004 continue through the fall of 1991 and into 1992.
6006 Other Modula-2 compilers are currently not supported, and attempting to
6007 debug programs compiled with them will likely result in an error as the
6008 symbol table is read. Feel free to work on it, though!
6010 There are hooks in GDB for strict type checking and range checking,
6011 in the `Modula-2 philosophy', but they do not currently work.
6015 GDB can now write to executable and core files (e.g. patch
6016 a variable's value). You must turn this switch on, specify
6017 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6018 by assigning a new value to a variable. Modifications take
6021 * Automatic SunOS shared library reading
6023 When you run your program, GDB automatically determines where its
6024 shared libraries (if any) have been loaded, and reads their symbols.
6025 The `share' command is no longer needed. This also works when
6026 examining core files.
6030 You can specify the number of lines that the `list' command shows.
6033 * New machines supported (host and target)
6035 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6036 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6037 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6039 * New hosts supported (not targets)
6041 IBM RT/PC: romp-ibm-aix or rtpc
6043 * New targets supported (not hosts)
6045 AMD 29000 embedded with COFF a29k-none-coff
6046 AMD 29000 embedded with a.out a29k-none-aout
6047 Ultracomputer remote kernel debug a29k-nyu-kern
6049 * New remote interfaces
6055 *** Changes in GDB-4.0:
6059 Wide output is wrapped at good places to make the output more readable.
6061 Gdb now supports cross-debugging from a host machine of one type to a
6062 target machine of another type. Communication with the target system
6063 is over serial lines. The ``target'' command handles connecting to the
6064 remote system; the ``load'' command will download a program into the
6065 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6066 also supports debugging of realtime processes running under VxWorks,
6067 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6068 stub on the target system.
6070 New CPUs supported include the AMD 29000 and Intel 960.
6072 GDB now reads object files and symbol tables via a ``binary file''
6073 library, which allows a single copy of GDB to debug programs of multiple
6074 object file types such as a.out and coff.
6076 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6077 refcard.dvi and refcard.ps are available to format it).
6080 * Control-Variable user interface simplified
6082 All variables that control the operation of the debugger can be set
6083 by the ``set'' command, and displayed by the ``show'' command.
6085 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6086 ``Show prompt'' produces the response:
6087 Gdb's prompt is new-gdb=>.
6089 What follows are the NEW set commands. The command ``help set'' will
6090 print a complete list of old and new set commands. ``help set FOO''
6091 will give a longer description of the variable FOO. ``show'' will show
6092 all of the variable descriptions and their current settings.
6094 confirm on/off: Enables warning questions for operations that are
6095 hard to recover from, e.g. rerunning the program while
6096 it is already running. Default is ON.
6098 editing on/off: Enables EMACS style command line editing
6099 of input. Previous lines can be recalled with
6100 control-P, the current line can be edited with control-B,
6101 you can search for commands with control-R, etc.
6104 history filename NAME: NAME is where the gdb command history
6105 will be stored. The default is .gdb_history,
6106 or the value of the environment variable
6109 history size N: The size, in commands, of the command history. The
6110 default is 256, or the value of the environment variable
6113 history save on/off: If this value is set to ON, the history file will
6114 be saved after exiting gdb. If set to OFF, the
6115 file will not be saved. The default is OFF.
6117 history expansion on/off: If this value is set to ON, then csh-like
6118 history expansion will be performed on
6119 command line input. The default is OFF.
6121 radix N: Sets the default radix for input and output. It can be set
6122 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6123 in the current radix, so "set radix 10" is always a no-op.
6125 height N: This integer value is the number of lines on a page. Default
6126 is 24, the current `stty rows'' setting, or the ``li#''
6127 setting from the termcap entry matching the environment
6130 width N: This integer value is the number of characters on a line.
6131 Default is 80, the current `stty cols'' setting, or the ``co#''
6132 setting from the termcap entry matching the environment
6135 Note: ``set screensize'' is obsolete. Use ``set height'' and
6136 ``set width'' instead.
6138 print address on/off: Print memory addresses in various command displays,
6139 such as stack traces and structure values. Gdb looks
6140 more ``symbolic'' if you turn this off; it looks more
6141 ``machine level'' with it on. Default is ON.
6143 print array on/off: Prettyprint arrays. New convenient format! Default
6146 print demangle on/off: Print C++ symbols in "source" form if on,
6149 print asm-demangle on/off: Same, for assembler level printouts
6152 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6155 * Support for Epoch Environment.
6157 The epoch environment is a version of Emacs v18 with windowing. One
6158 new command, ``inspect'', is identical to ``print'', except that if you
6159 are running in the epoch environment, the value is printed in its own
6163 * Support for Shared Libraries
6165 GDB can now debug programs and core files that use SunOS shared libraries.
6166 Symbols from a shared library cannot be referenced
6167 before the shared library has been linked with the program (this
6168 happens after you type ``run'' and before the function main() is entered).
6169 At any time after this linking (including when examining core files
6170 from dynamically linked programs), gdb reads the symbols from each
6171 shared library when you type the ``sharedlibrary'' command.
6172 It can be abbreviated ``share''.
6174 sharedlibrary REGEXP: Load shared object library symbols for files
6175 matching a unix regular expression. No argument
6176 indicates to load symbols for all shared libraries.
6178 info sharedlibrary: Status of loaded shared libraries.
6183 A watchpoint stops execution of a program whenever the value of an
6184 expression changes. Checking for this slows down execution
6185 tremendously whenever you are in the scope of the expression, but is
6186 quite useful for catching tough ``bit-spreader'' or pointer misuse
6187 problems. Some machines such as the 386 have hardware for doing this
6188 more quickly, and future versions of gdb will use this hardware.
6190 watch EXP: Set a watchpoint (breakpoint) for an expression.
6192 info watchpoints: Information about your watchpoints.
6194 delete N: Deletes watchpoint number N (same as breakpoints).
6195 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6196 enable N: Re-enables watchpoint number N (same as breakpoints).
6199 * C++ multiple inheritance
6201 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6204 * C++ exception handling
6206 Gdb now supports limited C++ exception handling. Besides the existing
6207 ability to breakpoint on an exception handler, gdb can breakpoint on
6208 the raising of an exception (before the stack is peeled back to the
6211 catch FOO: If there is a FOO exception handler in the dynamic scope,
6212 set a breakpoint to catch exceptions which may be raised there.
6213 Multiple exceptions (``catch foo bar baz'') may be caught.
6215 info catch: Lists all exceptions which may be caught in the
6216 current stack frame.
6219 * Minor command changes
6221 The command ``call func (arg, arg, ...)'' now acts like the print
6222 command, except it does not print or save a value if the function's result
6223 is void. This is similar to dbx usage.
6225 The ``up'' and ``down'' commands now always print the frame they end up
6226 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6227 frames without printing.
6229 * New directory command
6231 'dir' now adds directories to the FRONT of the source search path.
6232 The path starts off empty. Source files that contain debug information
6233 about the directory in which they were compiled can be found even
6234 with an empty path; Sun CC and GCC include this information. If GDB can't
6235 find your source file in the current directory, type "dir .".
6237 * Configuring GDB for compilation
6239 For normal use, type ``./configure host''. See README or gdb.texinfo
6242 GDB now handles cross debugging. If you are remotely debugging between
6243 two different machines, type ``./configure host -target=targ''.
6244 Host is the machine where GDB will run; targ is the machine
6245 where the program that you are debugging will run.