1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.10
6 * Per-inferior thread numbers
8 Thread numbers are now per inferior instead of global. If you're
9 debugging multiple inferiors, GDB displays thread IDs using a
10 qualified INF_NUM.THR_NUM form. For example:
14 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
15 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
16 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
17 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
19 As consequence, thread numbers as visible in the $_thread
20 convenience variable and in Python's InferiorThread.num attribute
21 are no longer unique between inferiors.
23 GDB now maintains a second thread ID per thread, referred to as the
24 global thread ID, which is the new equivalent of thread numbers in
27 For backwards compatibility, MI's thread IDs always refer to global
30 * Commands that accept thread IDs now accept the qualified
31 INF_NUM.THR_NUM form as well. For example:
34 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
37 * The new convenience variable $_inferior holds the number of the
40 * Record btrace now supports non-stop mode.
42 * Support for tracepoints on aarch64-linux was added in GDBserver.
44 * The 'record instruction-history' command now indicates speculative execution
45 when using the Intel Processor Trace recording format.
47 * GDB now allows users to specify explicit locations, bypassing
48 the linespec parser. This feature is also available to GDB/MI
51 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
52 GDB now is able to debug both AArch64 applications and ARM applications
55 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
56 including JIT compiling fast tracepoint's conditional expression bytecode
59 * GDB now supports displaced stepping on AArch64 GNU/Linux.
61 * "info threads", "info inferiors", "info display", "info checkpoints"
62 and "maint info program-spaces" now list the corresponding items in
63 ascending ID order, for consistency with all other "info" commands.
65 * In Ada, the overloads selection menu has been enhanced to display the
66 parameter types and the return types for the matching overloaded subprograms.
70 maint set target-non-stop (on|off|auto)
71 maint show target-non-stop
72 Control whether GDB targets always operate in non-stop mode even if
73 "set non-stop" is "off". The default is "auto", meaning non-stop
74 mode is enabled if supported by the target.
77 maint show bfd-sharing
78 Control the reuse of bfd objects.
82 Control display of debugging info regarding bfd caching.
84 set remote multiprocess-extensions-packet
85 show remote multiprocess-extensions-packet
86 Set/show the use of the remote protocol multiprocess extensions.
88 set remote thread-events
89 show remote thread-events
90 Set/show the use of thread create/exit events.
92 set ada print-signatures on|off
93 show ada print-signatures"
94 Control whether parameter types and return types are displayed in overloads
95 selection menus. It is activaled (@code{on}) by default.
97 * The "disassemble" command accepts a new modifier: /s.
98 It prints mixed source+disassembly like /m with two differences:
99 - disassembled instructions are now printed in program order, and
100 - and source for all relevant files is now printed.
101 The "/m" option is now considered deprecated: its "source-centric"
102 output hasn't proved useful in practice.
104 * The "record instruction-history" command accepts a new modifier: /s.
105 It behaves exactly like /m and prints mixed source+disassembly.
107 * The "set scheduler-locking" command supports a new mode "replay".
108 It behaves like "off" in record mode and like "on" in replay mode.
110 * Support for various ROM monitors has been removed:
112 target dbug dBUG ROM monitor for Motorola ColdFire
113 target picobug Motorola picobug monitor
114 target dink32 DINK32 ROM monitor for PowerPC
115 target m32r Renesas M32R/D ROM monitor
116 target mon2000 mon2000 ROM monitor
117 target ppcbug PPCBUG ROM monitor for PowerPC
119 * Support for reading/writing memory and extracting values on architectures
120 whose memory is addressable in units of any integral multiple of 8 bits.
125 Indicates that an exec system call was executed.
127 exec-events feature in qSupported
128 The qSupported packet allows GDB to request support for exec
129 events using the new 'gdbfeature' exec-event, and the qSupported
130 response can contain the corresponding 'stubfeature'. Set and
131 show commands can be used to display whether these features are enabled.
134 Equivalent to interrupting with the ^C character, but works in
137 thread created stop reason (T05 create:...)
138 Indicates that the thread was just created and is stopped at entry.
140 thread exit stop reply (w exitcode;tid)
141 Indicates that the thread has terminated.
144 Enables/disables thread create and exit event reporting. For
145 example, this is used in non-stop mode when GDB stops a set of
146 threads and synchronously waits for the their corresponding stop
147 replies. Without exit events, if one of the threads exits, GDB
148 would hang forever not knowing that it should no longer expect a
149 stop for that same thread.
153 Indicates that there are no resumed threads left in the target (all
154 threads are stopped). The remote stub reports support for this stop
155 reply to GDB's qSupported query.
157 QCatchSyscalls:1 [;SYSNO]...
159 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
160 catching syscalls from the inferior process.
162 syscall_entry stop reason
163 Indicates that a syscall was just called.
165 syscall_return stop reason
166 Indicates that a syscall just returned.
168 QCatchSyscalls:1 in qSupported
169 The qSupported packet may now include QCatchSyscalls:1 in the reply
170 to indicate support for catching syscalls.
172 * Extended-remote exec events
174 ** GDB now has support for exec events on extended-remote Linux targets.
175 For such targets with Linux kernels 2.5.46 and later, this enables
176 follow-exec-mode and exec catchpoints.
178 set remote exec-event-feature-packet
179 show remote exec-event-feature-packet
180 Set/show the use of the remote exec event feature.
182 * Thread names in remote protocol
184 The reply to qXfer:threads:read may now include a name attribute for each
187 * Target remote mode fork and exec events
189 ** GDB now has support for fork and exec events on target remote mode
190 Linux targets. For such targets with Linux kernels 2.5.46 and later,
191 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
192 fork and exec catchpoints.
194 * Remote syscall events
196 ** GDB now has support for catch syscall on remote Linux targets,
197 currently enabled on x86/x86_64 architectures.
199 set remote catch-syscall-packet
200 show remote catch-syscall-packet
201 Set/show the use of the remote catch syscall feature.
205 ** The -var-set-format command now accepts the zero-hexadecimal
206 format. It outputs data in hexadecimal format with zero-padding on the
211 ** gdb.InferiorThread objects have a new attribute "global_num",
212 which refers to the thread's global thread ID. The existing
213 "num" attribute now refers to the thread's per-inferior number.
214 See "Per-inferior thread numbers" above.
215 ** gdb.InferiorThread objects have a new attribute "inferior", which
216 is the Inferior object the thread belongs to.
218 *** Changes in GDB 7.10
220 * Support for process record-replay and reverse debugging on aarch64*-linux*
221 targets has been added. GDB now supports recording of A64 instruction set
222 including advance SIMD instructions.
224 * Support for Sun's version of the "stabs" debug file format has been removed.
226 * GDB now honors the content of the file /proc/PID/coredump_filter
227 (PID is the process ID) on GNU/Linux systems. This file can be used
228 to specify the types of memory mappings that will be included in a
229 corefile. For more information, please refer to the manual page of
230 "core(5)". GDB also has a new command: "set use-coredump-filter
231 on|off". It allows to set whether GDB will read the content of the
232 /proc/PID/coredump_filter file when generating a corefile.
234 * The "info os" command on GNU/Linux can now display information on
236 "info os cpus" Listing of all cpus/cores on the system
238 * GDB has two new commands: "set serial parity odd|even|none" and
239 "show serial parity". These allows to set or show parity for the
242 * The "info source" command now displays the producer string if it was
243 present in the debug info. This typically includes the compiler version
244 and may include things like its command line arguments.
246 * The "info dll", an alias of the "info sharedlibrary" command,
247 is now available on all platforms.
249 * Directory names supplied to the "set sysroot" commands may be
250 prefixed with "target:" to tell GDB to access shared libraries from
251 the target system, be it local or remote. This replaces the prefix
252 "remote:". The default sysroot has been changed from "" to
253 "target:". "remote:" is automatically converted to "target:" for
254 backward compatibility.
256 * The system root specified by "set sysroot" will be prepended to the
257 filename of the main executable (if reported to GDB as absolute by
258 the operating system) when starting processes remotely, and when
259 attaching to already-running local or remote processes.
261 * GDB now supports automatic location and retrieval of executable
262 files from remote targets. Remote debugging can now be initiated
263 using only a "target remote" or "target extended-remote" command
264 (no "set sysroot" or "file" commands are required). See "New remote
267 * The "dump" command now supports verilog hex format.
269 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
271 * On GNU/Linux, GDB and gdbserver are now able to access executable
272 and shared library files without a "set sysroot" command when
273 attaching to processes running in different mount namespaces from
274 the debugger. This makes it possible to attach to processes in
275 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
276 See "New remote packets" below.
278 * The "tui reg" command now provides completion for all of the
279 available register groups, including target specific groups.
281 * The HISTSIZE environment variable is no longer read when determining
282 the size of GDB's command history. GDB now instead reads the dedicated
283 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
284 disables truncation of command history. Non-numeric values of GDBHISTSIZE
289 ** Memory ports can now be unbuffered.
293 ** gdb.Objfile objects have a new attribute "username",
294 which is the name of the objfile as specified by the user,
295 without, for example, resolving symlinks.
296 ** You can now write frame unwinders in Python.
297 ** gdb.Type objects have a new method "optimized_out",
298 returning optimized out gdb.Value instance of this type.
299 ** gdb.Value objects have new methods "reference_value" and
300 "const_value" which return a reference to the value and a
301 "const" version of the value respectively.
305 maint print symbol-cache
306 Print the contents of the symbol cache.
308 maint print symbol-cache-statistics
309 Print statistics of symbol cache usage.
311 maint flush-symbol-cache
312 Flush the contents of the symbol cache.
316 Start branch trace recording using Branch Trace Store (BTS) format.
319 Evaluate expression by using the compiler and print result.
323 Explicit commands for enabling and disabling tui mode.
326 set mpx bound on i386 and amd64
327 Support for bound table investigation on Intel MPX enabled applications.
331 Start branch trace recording using Intel Processor Trace format.
334 Print information about branch tracing internals.
336 maint btrace packet-history
337 Print the raw branch tracing data.
339 maint btrace clear-packet-history
340 Discard the stored raw branch tracing data.
343 Discard all branch tracing data. It will be fetched and processed
344 anew by the next "record" command.
349 Renamed from "set debug dwarf2-die".
351 Renamed from "show debug dwarf2-die".
354 Renamed from "set debug dwarf2-read".
355 show debug dwarf-read
356 Renamed from "show debug dwarf2-read".
358 maint set dwarf always-disassemble
359 Renamed from "maint set dwarf2 always-disassemble".
360 maint show dwarf always-disassemble
361 Renamed from "maint show dwarf2 always-disassemble".
363 maint set dwarf max-cache-age
364 Renamed from "maint set dwarf2 max-cache-age".
365 maint show dwarf max-cache-age
366 Renamed from "maint show dwarf2 max-cache-age".
369 show debug dwarf-line
370 Control display of debugging info regarding DWARF line processing.
374 Set the maximum number of candidates to be considered during
375 completion. The default value is 200. This limit allows GDB
376 to avoid generating large completion lists, the computation of
377 which can cause the debugger to become temporarily unresponsive.
379 set history remove-duplicates
380 show history remove-duplicates
381 Control the removal of duplicate history entries.
383 maint set symbol-cache-size
384 maint show symbol-cache-size
385 Control the size of the symbol cache.
387 set|show record btrace bts buffer-size
388 Set and show the size of the ring buffer used for branch tracing in
390 The obtained size may differ from the requested size. Use "info
391 record" to see the obtained buffer size.
393 set debug linux-namespaces
394 show debug linux-namespaces
395 Control display of debugging info regarding Linux namespaces.
397 set|show record btrace pt buffer-size
398 Set and show the size of the ring buffer used for branch tracing in
399 Intel Processor Trace format.
400 The obtained size may differ from the requested size. Use "info
401 record" to see the obtained buffer size.
403 maint set|show btrace pt skip-pad
404 Set and show whether PAD packets are skipped when computing the
407 * The command 'thread apply all' can now support new option '-ascending'
408 to call its specified command for all threads in ascending order.
410 * Python/Guile scripting
412 ** GDB now supports auto-loading of Python/Guile scripts contained in the
413 special section named `.debug_gdb_scripts'.
417 qXfer:btrace-conf:read
418 Return the branch trace configuration for the current thread.
420 Qbtrace-conf:bts:size
421 Set the requested ring buffer size for branch tracing in BTS format.
424 Enable Intel Procesor Trace-based branch tracing for the current
425 process. The remote stub reports support for this packet to GDB's
429 Set the requested ring buffer size for branch tracing in Intel Processor
433 Indicates a memory breakpoint instruction was executed, irrespective
434 of whether it was GDB that planted the breakpoint or the breakpoint
435 is hardcoded in the program. This is required for correct non-stop
439 Indicates the target stopped for a hardware breakpoint. This is
440 required for correct non-stop mode operation.
443 Return information about files on the remote system.
446 Return the full absolute name of the file that was executed to
447 create a process running on the remote system.
450 Select the filesystem on which vFile: operations with filename
451 arguments will operate. This is required for GDB to be able to
452 access files on remote targets where the remote stub does not
453 share a common filesystem with the inferior(s).
456 Indicates that a fork system call was executed.
459 Indicates that a vfork system call was executed.
461 vforkdone stop reason
462 Indicates that a vfork child of the specified process has executed
463 an exec or exit, allowing the vfork parent to resume execution.
465 fork-events and vfork-events features in qSupported
466 The qSupported packet allows GDB to request support for fork and
467 vfork events using new 'gdbfeatures' fork-events and vfork-events,
468 and the qSupported response can contain the corresponding
469 'stubfeatures'. Set and show commands can be used to display
470 whether these features are enabled.
472 * Extended-remote fork events
474 ** GDB now has support for fork events on extended-remote Linux
475 targets. For targets with Linux kernels 2.5.60 and later, this
476 enables follow-fork-mode and detach-on-fork for both fork and
477 vfork, as well as fork and vfork catchpoints.
479 * The info record command now shows the recording format and the
480 branch tracing configuration for the current thread when using
481 the btrace record target.
482 For the BTS format, it shows the ring buffer size.
484 * GDB now has support for DTrace USDT (Userland Static Defined
485 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
487 * GDB now supports access to vector registers on S/390 GNU/Linux
490 * Removed command line options
492 -xdb HP-UX XDB compatibility mode.
494 * Removed targets and native configurations
496 HP/PA running HP-UX hppa*-*-hpux*
497 Itanium running HP-UX ia64-*-hpux*
499 * New configure options
502 This configure option allows the user to build GDB with support for
503 Intel Processor Trace (default: auto). This requires libipt.
505 --with-libipt-prefix=PATH
506 Specify the path to the version of libipt that GDB should use.
507 $PATH/include should contain the intel-pt.h header and
508 $PATH/lib should contain the libipt.so library.
510 *** Changes in GDB 7.9.1
514 ** Xmethods can now specify a result type.
516 *** Changes in GDB 7.9
518 * GDB now supports hardware watchpoints on x86 GNU Hurd.
522 ** You can now access frame registers from Python scripts.
523 ** New attribute 'producer' for gdb.Symtab objects.
524 ** gdb.Objfile objects have a new attribute "progspace",
525 which is the gdb.Progspace object of the containing program space.
526 ** gdb.Objfile objects have a new attribute "owner".
527 ** gdb.Objfile objects have a new attribute "build_id",
528 which is the build ID generated when the file was built.
529 ** gdb.Objfile objects have a new method "add_separate_debug_file".
530 ** A new event "gdb.clear_objfiles" has been added, triggered when
531 selecting a new file to debug.
532 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
533 ** New function gdb.lookup_objfile.
535 New events which are triggered when GDB modifies the state of the
538 ** gdb.events.inferior_call_pre: Function call is about to be made.
539 ** gdb.events.inferior_call_post: Function call has just been made.
540 ** gdb.events.memory_changed: A memory location has been altered.
541 ** gdb.events.register_changed: A register has been altered.
543 * New Python-based convenience functions:
545 ** $_caller_is(name [, number_of_frames])
546 ** $_caller_matches(regexp [, number_of_frames])
547 ** $_any_caller_is(name [, number_of_frames])
548 ** $_any_caller_matches(regexp [, number_of_frames])
550 * GDB now supports the compilation and injection of source code into
551 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
552 to compile the source code to object code, and if successful, inject
553 and execute that code within the current context of the inferior.
554 Currently the C language is supported. The commands used to
555 interface with this new feature are:
557 compile code [-raw|-r] [--] [source code]
558 compile file [-raw|-r] filename
562 demangle [-l language] [--] name
563 Demangle "name" in the specified language, or the current language
564 if elided. This command is renamed from the "maint demangle" command.
565 The latter is kept as a no-op to avoid "maint demangle" being interpreted
566 as "maint demangler-warning".
568 queue-signal signal-name-or-number
569 Queue a signal to be delivered to the thread when it is resumed.
571 add-auto-load-scripts-directory directory
572 Add entries to the list of directories from which to load auto-loaded
575 maint print user-registers
576 List all currently available "user" registers.
578 compile code [-r|-raw] [--] [source code]
579 Compile, inject, and execute in the inferior the executable object
580 code produced by compiling the provided source code.
582 compile file [-r|-raw] filename
583 Compile and inject into the inferior the executable object code
584 produced by compiling the source code stored in the filename
587 * On resume, GDB now always passes the signal the program had stopped
588 for to the thread the signal was sent to, even if the user changed
589 threads before resuming. Previously GDB would often (but not
590 always) deliver the signal to the thread that happens to be current
593 * Conversely, the "signal" command now consistently delivers the
594 requested signal to the current thread. GDB now asks for
595 confirmation if the program had stopped for a signal and the user
596 switched threads meanwhile.
598 * "breakpoint always-inserted" modes "off" and "auto" merged.
600 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
601 won't remove breakpoints from the target until all threads stop,
602 even in non-stop mode. The "auto" mode has been removed, and "off"
603 is now the default mode.
607 set debug symbol-lookup
608 show debug symbol-lookup
609 Control display of debugging info regarding symbol lookup.
613 ** The -list-thread-groups command outputs an exit-code field for
614 inferiors that have exited.
618 MIPS SDE mips*-sde*-elf*
622 Support for these obsolete configurations has been removed.
624 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
625 SGI Irix-5.x mips-*-irix5*
626 SGI Irix-6.x mips-*-irix6*
627 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
628 VAX running Ultrix vax-*-ultrix*
630 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
631 and "assf"), have been removed. Use the "sharedlibrary" command, or
632 its alias "share", instead.
634 *** Changes in GDB 7.8
636 * New command line options
639 This is an alias for the --data-directory option.
641 * GDB supports printing and modifying of variable length automatic arrays
642 as specified in ISO C99.
644 * The ARM simulator now supports instruction level tracing
645 with or without disassembly.
649 GDB now has support for scripting using Guile. Whether this is
650 available is determined at configure time.
651 Guile version 2.0 or greater is required.
652 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
654 * New commands (for set/show, see "New options" below)
658 Invoke CODE by passing it to the Guile interpreter.
662 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
664 info auto-load guile-scripts [regexp]
665 Print the list of automatically loaded Guile scripts.
667 * The source command is now capable of sourcing Guile scripts.
668 This feature is dependent on the debugger being built with Guile support.
672 set print symbol-loading (off|brief|full)
673 show print symbol-loading
674 Control whether to print informational messages when loading symbol
675 information for a file. The default is "full", but when debugging
676 programs with large numbers of shared libraries the amount of output
679 set guile print-stack (none|message|full)
680 show guile print-stack
681 Show a stack trace when an error is encountered in a Guile script.
683 set auto-load guile-scripts (on|off)
684 show auto-load guile-scripts
685 Control auto-loading of Guile script files.
687 maint ada set ignore-descriptive-types (on|off)
688 maint ada show ignore-descriptive-types
689 Control whether the debugger should ignore descriptive types in Ada
690 programs. The default is not to ignore the descriptive types. See
691 the user manual for more details on descriptive types and the intended
692 usage of this option.
694 set auto-connect-native-target
696 Control whether GDB is allowed to automatically connect to the
697 native target for the run, attach, etc. commands when not connected
698 to any target yet. See also "target native" below.
700 set record btrace replay-memory-access (read-only|read-write)
701 show record btrace replay-memory-access
702 Control what memory accesses are allowed during replay.
704 maint set target-async (on|off)
705 maint show target-async
706 This controls whether GDB targets operate in synchronous or
707 asynchronous mode. Normally the default is asynchronous, if it is
708 available; but this can be changed to more easily debug problems
709 occurring only in synchronous mode.
711 set mi-async (on|off)
713 Control whether MI asynchronous mode is preferred. This supersedes
714 "set target-async" of previous GDB versions.
716 * "set target-async" is deprecated as a CLI option and is now an alias
717 for "set mi-async" (only puts MI into async mode).
719 * Background execution commands (e.g., "c&", "s&", etc.) are now
720 possible ``out of the box'' if the target supports them. Previously
721 the user would need to explicitly enable the possibility with the
722 "set target-async on" command.
724 * New features in the GDB remote stub, GDBserver
726 ** New option --debug-format=option1[,option2,...] allows one to add
727 additional text to each output. At present only timestamps
728 are supported: --debug-format=timestamps.
729 Timestamps can also be turned on with the
730 "monitor set debug-format timestamps" command from GDB.
732 * The 'record instruction-history' command now starts counting instructions
733 at one. This also affects the instruction ranges reported by the
734 'record function-call-history' command when given the /i modifier.
736 * The command 'record function-call-history' supports a new modifier '/c' to
737 indent the function names based on their call stack depth.
738 The fields for the '/i' and '/l' modifier have been reordered.
739 The source line range is now prefixed with 'at'.
740 The instruction range is now prefixed with 'inst'.
741 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
742 "record instruction-history" and "list" commands.
744 * The ranges given as arguments to the 'record function-call-history' and
745 'record instruction-history' commands are now inclusive.
747 * The btrace record target now supports the 'record goto' command.
748 For locations inside the execution trace, the back trace is computed
749 based on the information stored in the execution trace.
751 * The btrace record target supports limited reverse execution and replay.
752 The target does not record data and therefore does not allow reading
755 * The "catch syscall" command now works on s390*-linux* targets.
757 * The "compare-sections" command is no longer specific to target
758 remote. It now works with all targets.
760 * All native targets are now consistently called "native".
761 Consequently, the "target child", "target GNU", "target djgpp",
762 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
763 commands have been replaced with "target native". The QNX/NTO port
764 leaves the "procfs" target in place and adds a "native" target for
765 consistency with other ports. The impact on users should be minimal
766 as these commands previously either throwed an error, or were
767 no-ops. The target's name is visible in the output of the following
768 commands: "help target", "info target", "info files", "maint print
771 * The "target native" command now connects to the native target. This
772 can be used to launch native programs even when "set
773 auto-connect-native-target" is set to off.
775 * GDB now supports access to Intel MPX registers on GNU/Linux.
777 * Support for Intel AVX-512 registers on GNU/Linux.
778 Support displaying and modifying Intel AVX-512 registers
779 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
783 qXfer:btrace:read's annex
784 The qXfer:btrace:read packet supports a new annex 'delta' to read
785 branch trace incrementally.
789 ** Valid Python operations on gdb.Value objects representing
790 structs/classes invoke the corresponding overloaded operators if
792 ** New `Xmethods' feature in the Python API. Xmethods are
793 additional methods or replacements for existing methods of a C++
794 class. This feature is useful for those cases where a method
795 defined in C++ source code could be inlined or optimized out by
796 the compiler, making it unavailable to GDB.
799 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
801 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
802 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
803 its alias "share", instead.
805 * The commands "set remotebaud" and "show remotebaud" are no longer
806 supported. Use "set serial baud" and "show serial baud" (respectively)
811 ** A new option "-gdb-set mi-async" replaces "-gdb-set
812 target-async". The latter is left as a deprecated alias of the
813 former for backward compatibility. If the target supports it,
814 CLI background execution commands are now always possible by
815 default, independently of whether the frontend stated a
816 preference for asynchronous execution with "-gdb-set mi-async".
817 Previously "-gdb-set target-async off" affected both MI execution
818 commands and CLI execution commands.
820 *** Changes in GDB 7.7
822 * Improved support for process record-replay and reverse debugging on
823 arm*-linux* targets. Support for thumb32 and syscall instruction
824 recording has been added.
826 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
828 * GDB now supports Fission DWP file format version 2.
829 http://gcc.gnu.org/wiki/DebugFission
831 * New convenience function "$_isvoid", to check whether an expression
832 is void. A void expression is an expression where the type of the
833 result is "void". For example, some convenience variables may be
834 "void" when evaluated (e.g., "$_exitcode" before the execution of
835 the program being debugged; or an undefined convenience variable).
836 Another example, when calling a function whose return type is
839 * The "maintenance print objfiles" command now takes an optional regexp.
841 * The "catch syscall" command now works on arm*-linux* targets.
843 * GDB now consistently shows "<not saved>" when printing values of
844 registers the debug info indicates have not been saved in the frame
845 and there's nowhere to retrieve them from
846 (callee-saved/call-clobbered registers):
851 (gdb) info registers rax
854 Before, the former would print "<optimized out>", and the latter
855 "*value not available*".
857 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
862 ** Frame filters and frame decorators have been added.
863 ** Temporary breakpoints are now supported.
864 ** Line tables representation has been added.
865 ** New attribute 'parent_type' for gdb.Field objects.
866 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
867 ** New attribute 'name' for gdb.Type objects.
871 Nios II ELF nios2*-*-elf
872 Nios II GNU/Linux nios2*-*-linux
873 Texas Instruments MSP430 msp430*-*-elf
875 * Removed native configurations
877 Support for these a.out NetBSD and OpenBSD obsolete configurations has
878 been removed. ELF variants of these configurations are kept supported.
880 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
881 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
882 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
883 i[34567]86-*-openbsd3.[0-3]
884 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
885 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
886 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
890 Like "catch throw", but catches a re-thrown exception.
892 Renamed from old "maint check-symtabs".
894 Perform consistency checks on symtabs.
896 Expand symtabs matching an optional regexp.
899 Display the details of GDB configure-time options.
901 maint set|show per-command
902 maint set|show per-command space
903 maint set|show per-command time
904 maint set|show per-command symtab
905 Enable display of per-command gdb resource usage.
907 remove-symbol-file FILENAME
908 remove-symbol-file -a ADDRESS
909 Remove a symbol file added via add-symbol-file. The file to remove
910 can be identified by its filename or by an address that lies within
911 the boundaries of this symbol file in memory.
914 info exceptions REGEXP
915 Display the list of Ada exceptions defined in the program being
916 debugged. If provided, only the exceptions whose names match REGEXP
921 set debug symfile off|on
923 Control display of debugging info regarding reading symbol files and
924 symbol tables within those files
926 set print raw frame-arguments
927 show print raw frame-arguments
928 Set/show whether to print frame arguments in raw mode,
929 disregarding any defined pretty-printers.
931 set remote trace-status-packet
932 show remote trace-status-packet
933 Set/show the use of remote protocol qTStatus packet.
937 Control display of debugging messages related to Nios II targets.
941 Control whether target-assisted range stepping is enabled.
943 set startup-with-shell
944 show startup-with-shell
945 Specifies whether Unix child processes are started via a shell or
950 Use the target memory cache for accesses to the code segment. This
951 improves performance of remote debugging (particularly disassembly).
953 * You can now use a literal value 'unlimited' for options that
954 interpret 0 or -1 as meaning "unlimited". E.g., "set
955 trace-buffer-size unlimited" is now an alias for "set
956 trace-buffer-size -1" and "set height unlimited" is now an alias for
959 * The "set debug symtab-create" debugging option of GDB has been changed to
960 accept a verbosity level. 0 means "off", 1 provides basic debugging
961 output, and values of 2 or greater provides more verbose output.
963 * New command-line options
965 Display the details of GDB configure-time options.
967 * The command 'tsave' can now support new option '-ctf' to save trace
968 buffer in Common Trace Format.
970 * Newly installed $prefix/bin/gcore acts as a shell interface for the
973 * GDB now implements the the C++ 'typeid' operator.
975 * The new convenience variable $_exception holds the exception being
976 thrown or caught at an exception-related catchpoint.
978 * The exception-related catchpoints, like "catch throw", now accept a
979 regular expression which can be used to filter exceptions by type.
981 * The new convenience variable $_exitsignal is automatically set to
982 the terminating signal number when the program being debugged dies
983 due to an uncaught signal.
987 ** All MI commands now accept an optional "--language" option.
988 Support for this feature can be verified by using the "-list-features"
989 command, which should contain "language-option".
991 ** The new command -info-gdb-mi-command allows the user to determine
992 whether a GDB/MI command is supported or not.
994 ** The "^error" result record returned when trying to execute an undefined
995 GDB/MI command now provides a variable named "code" whose content is the
996 "undefined-command" error code. Support for this feature can be verified
997 by using the "-list-features" command, which should contain
998 "undefined-command-error-code".
1000 ** The -trace-save MI command can optionally save trace buffer in Common
1003 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1005 ** The command -data-list-register-values now accepts an optional
1006 "--skip-unavailable" option. When used, only the available registers
1009 ** The new command -trace-frame-collected dumps collected variables,
1010 computed expressions, tvars, memory and registers in a traceframe.
1012 ** The commands -stack-list-locals, -stack-list-arguments and
1013 -stack-list-variables now accept an option "--skip-unavailable".
1014 When used, only the available locals or arguments are displayed.
1016 ** The -exec-run command now accepts an optional "--start" option.
1017 When used, the command follows the same semantics as the "start"
1018 command, stopping the program's execution at the start of its
1019 main subprogram. Support for this feature can be verified using
1020 the "-list-features" command, which should contain
1021 "exec-run-start-option".
1023 ** The new commands -catch-assert and -catch-exceptions insert
1024 catchpoints stopping the program when Ada exceptions are raised.
1026 ** The new command -info-ada-exceptions provides the equivalent of
1027 the new "info exceptions" command.
1029 * New system-wide configuration scripts
1030 A GDB installation now provides scripts suitable for use as system-wide
1031 configuration scripts for the following systems:
1035 * GDB now supports target-assigned range stepping with remote targets.
1036 This improves the performance of stepping source lines by reducing
1037 the number of control packets from/to GDB. See "New remote packets"
1040 * GDB now understands the element 'tvar' in the XML traceframe info.
1041 It has the id of the collected trace state variables.
1043 * On S/390 targets that provide the transactional-execution feature,
1044 the program interruption transaction diagnostic block (TDB) is now
1045 represented as a number of additional "registers" in GDB.
1047 * New remote packets
1051 The vCont packet supports a new 'r' action, that tells the remote
1052 stub to step through an address range itself, without GDB
1053 involvemement at each single-step.
1055 qXfer:libraries-svr4:read's annex
1056 The previously unused annex of the qXfer:libraries-svr4:read packet
1057 is now used to support passing an argument list. The remote stub
1058 reports support for this argument list to GDB's qSupported query.
1059 The defined arguments are "start" and "prev", used to reduce work
1060 necessary for library list updating, resulting in significant
1063 * New features in the GDB remote stub, GDBserver
1065 ** GDBserver now supports target-assisted range stepping. Currently
1066 enabled on x86/x86_64 GNU/Linux targets.
1068 ** GDBserver now adds element 'tvar' in the XML in the reply to
1069 'qXfer:traceframe-info:read'. It has the id of the collected
1070 trace state variables.
1072 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1075 * New 'z' formatter for printing and examining memory, this displays the
1076 value as hexadecimal zero padded on the left to the size of the type.
1078 * GDB can now use Windows x64 unwinding data.
1080 * The "set remotebaud" command has been replaced by "set serial baud".
1081 Similarly, "show remotebaud" has been replaced by "show serial baud".
1082 The "set remotebaud" and "show remotebaud" commands are still available
1083 to provide backward compatibility with older versions of GDB.
1085 *** Changes in GDB 7.6
1087 * Target record has been renamed to record-full.
1088 Record/replay is now enabled with the "record full" command.
1089 This also affects settings that are associated with full record/replay
1090 that have been moved from "set/show record" to "set/show record full":
1092 set|show record full insn-number-max
1093 set|show record full stop-at-limit
1094 set|show record full memory-query
1096 * A new record target "record-btrace" has been added. The new target
1097 uses hardware support to record the control-flow of a process. It
1098 does not support replaying the execution, but it implements the
1099 below new commands for investigating the recorded execution log.
1100 This new recording method can be enabled using:
1104 The "record-btrace" target is only available on Intel Atom processors
1105 and requires a Linux kernel 2.6.32 or later.
1107 * Two new commands have been added for record/replay to give information
1108 about the recorded execution without having to replay the execution.
1109 The commands are only supported by "record btrace".
1111 record instruction-history prints the execution history at
1112 instruction granularity
1114 record function-call-history prints the execution history at
1115 function granularity
1117 * New native configurations
1119 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1120 FreeBSD/powerpc powerpc*-*-freebsd
1121 x86_64/Cygwin x86_64-*-cygwin*
1122 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1126 ARM AArch64 aarch64*-*-elf
1127 ARM AArch64 GNU/Linux aarch64*-*-linux
1128 Lynx 178 PowerPC powerpc-*-lynx*178
1129 x86_64/Cygwin x86_64-*-cygwin*
1130 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1132 * If the configured location of system.gdbinit file (as given by the
1133 --with-system-gdbinit option at configure time) is in the
1134 data-directory (as specified by --with-gdb-datadir at configure
1135 time) or in one of its subdirectories, then GDB will look for the
1136 system-wide init file in the directory specified by the
1137 --data-directory command-line option.
1139 * New command line options:
1141 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1142 other initialization files, unlike -nx which disables all of them.
1144 * Removed command line options
1146 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1149 * The 'ptype' and 'whatis' commands now accept an argument to control
1152 * 'info proc' now works on some core files.
1156 ** Vectors can be created with gdb.Type.vector.
1158 ** Python's atexit.register now works in GDB.
1160 ** Types can be pretty-printed via a Python API.
1162 ** Python 3 is now supported (in addition to Python 2.4 or later)
1164 ** New class gdb.Architecture exposes GDB's internal representation
1165 of architecture in the Python API.
1167 ** New method Frame.architecture returns the gdb.Architecture object
1168 corresponding to the frame's architecture.
1170 * New Python-based convenience functions:
1172 ** $_memeq(buf1, buf2, length)
1173 ** $_streq(str1, str2)
1175 ** $_regex(str, regex)
1177 * The 'cd' command now defaults to using '~' (the home directory) if not
1180 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1181 default for GCC since November 2000.
1183 * The command 'forward-search' can now be abbreviated as 'fo'.
1185 * The command 'info tracepoints' can now display 'installed on target'
1186 or 'not installed on target' for each non-pending location of tracepoint.
1188 * New configure options
1190 --enable-libmcheck/--disable-libmcheck
1191 By default, development versions are built with -lmcheck on hosts
1192 that support it, in order to help track memory corruption issues.
1193 Release versions, on the other hand, are built without -lmcheck
1194 by default. The --enable-libmcheck/--disable-libmcheck configure
1195 options allow the user to override that default.
1196 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1197 This configure option allows the user to build GDB with
1198 libbabeltrace using which GDB can read Common Trace Format data.
1200 * New commands (for set/show, see "New options" below)
1203 Catch signals. This is similar to "handle", but allows commands and
1204 conditions to be attached.
1207 List the BFDs known to GDB.
1209 python-interactive [command]
1211 Start a Python interactive prompt, or evaluate the optional command
1212 and print the result of expressions.
1215 "py" is a new alias for "python".
1217 enable type-printer [name]...
1218 disable type-printer [name]...
1219 Enable or disable type printers.
1223 ** For the Renesas Super-H architecture, the "regs" command has been removed
1224 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1229 set print type methods (on|off)
1230 show print type methods
1231 Control whether method declarations are displayed by "ptype".
1232 The default is to show them.
1234 set print type typedefs (on|off)
1235 show print type typedefs
1236 Control whether typedef definitions are displayed by "ptype".
1237 The default is to show them.
1239 set filename-display basename|relative|absolute
1240 show filename-display
1241 Control the way in which filenames is displayed.
1242 The default is "relative", which preserves previous behavior.
1244 set trace-buffer-size
1245 show trace-buffer-size
1246 Request target to change the size of trace buffer.
1248 set remote trace-buffer-size-packet auto|on|off
1249 show remote trace-buffer-size-packet
1250 Control the use of the remote protocol `QTBuffer:size' packet.
1254 Control display of debugging messages related to ARM AArch64.
1257 set debug coff-pe-read
1258 show debug coff-pe-read
1259 Control display of debugging messages related to reading of COFF/PE
1264 Control display of debugging messages related to Mach-O symbols
1267 set debug notification
1268 show debug notification
1269 Control display of debugging info for async remote notification.
1273 ** Command parameter changes are now notified using new async record
1274 "=cmd-param-changed".
1275 ** Trace frame changes caused by command "tfind" are now notified using
1276 new async record "=traceframe-changed".
1277 ** The creation, deletion and modification of trace state variables
1278 are now notified using new async records "=tsv-created",
1279 "=tsv-deleted" and "=tsv-modified".
1280 ** The start and stop of process record are now notified using new
1281 async record "=record-started" and "=record-stopped".
1282 ** Memory changes are now notified using new async record
1284 ** The data-disassemble command response will include a "fullname" field
1285 containing the absolute file name when source has been requested.
1286 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1287 command, to allow pattern filling of memory areas.
1288 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1289 library load/unload events.
1290 ** The response to breakpoint commands and breakpoint async records
1291 includes an "installed" field containing a boolean state about each
1292 non-pending tracepoint location is whether installed on target or not.
1293 ** Output of the "-trace-status" command includes a "trace-file" field
1294 containing the name of the trace file being examined. This field is
1295 optional, and only present when examining a trace file.
1296 ** The "fullname" field is now always present along with the "file" field,
1297 even if the file cannot be found by GDB.
1299 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1300 You must have the LZMA library available when configuring GDB for this
1301 feature to be enabled. For more information, see:
1302 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1304 * New remote packets
1307 Set the size of trace buffer. The remote stub reports support for this
1308 packet to gdb's qSupported query.
1311 Enable Branch Trace Store (BTS)-based branch tracing for the current
1312 thread. The remote stub reports support for this packet to gdb's
1316 Disable branch tracing for the current thread. The remote stub reports
1317 support for this packet to gdb's qSupported query.
1320 Read the traced branches for the current thread. The remote stub
1321 reports support for this packet to gdb's qSupported query.
1323 *** Changes in GDB 7.5
1325 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1326 for more x32 ABI info.
1328 * GDB now supports access to MIPS DSP registers on Linux targets.
1330 * GDB now supports debugging microMIPS binaries.
1332 * The "info os" command on GNU/Linux can now display information on
1333 several new classes of objects managed by the operating system:
1334 "info os procgroups" lists process groups
1335 "info os files" lists file descriptors
1336 "info os sockets" lists internet-domain sockets
1337 "info os shm" lists shared-memory regions
1338 "info os semaphores" lists semaphores
1339 "info os msg" lists message queues
1340 "info os modules" lists loaded kernel modules
1342 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1343 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1344 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1345 options and inspect the probe arguments using the new $_probe_arg family
1346 of convenience variables. You can obtain more information about SystemTap
1347 in <http://sourceware.org/systemtap/>.
1349 * GDB now supports reversible debugging on ARM, it allows you to
1350 debug basic ARM and THUMB instructions, and provides
1351 record/replay support.
1353 * The option "symbol-reloading" has been deleted as it is no longer used.
1357 ** GDB commands implemented in Python can now be put in command class
1360 ** The "maint set python print-stack on|off" is now deleted.
1362 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1363 apply "flag enum"-style pretty-printing to any enum.
1365 ** gdb.lookup_symbol can now work when there is no current frame.
1367 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1368 the source at which the symbol was defined.
1370 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1371 method 'value'. The former indicates whether the symbol needs a
1372 frame in order to compute its value, and the latter computes the
1375 ** A new method 'referenced_value' on gdb.Value objects which can
1376 dereference pointer as well as C++ reference values.
1378 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1379 which return the global and static blocks (as gdb.Block objects),
1380 of the underlying symbol table, respectively.
1382 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1383 object associated with a PC value.
1385 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1386 of the address range occupied by code for the current source line.
1388 * Go language support.
1389 GDB now supports debugging programs written in the Go programming
1392 * GDBserver now supports stdio connections.
1393 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1395 * The binary "gdbtui" can no longer be built or installed.
1396 Use "gdb -tui" instead.
1398 * GDB will now print "flag" enums specially. A flag enum is one where
1399 all the enumerator values have no bits in common when pairwise
1400 "and"ed. When printing a value whose type is a flag enum, GDB will
1401 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1402 (gdb) print (enum E) 3
1405 * The filename part of a linespec will now match trailing components
1406 of a source file name. For example, "break gcc/expr.c:1000" will
1407 now set a breakpoint in build/gcc/expr.c, but not
1408 build/libcpp/expr.c.
1410 * The "info proc" and "generate-core-file" commands will now also
1411 work on remote targets connected to GDBserver on Linux.
1413 * The command "info catch" has been removed. It has been disabled
1414 since December 2007.
1416 * The "catch exception" and "catch assert" commands now accept
1417 a condition at the end of the command, much like the "break"
1418 command does. For instance:
1420 (gdb) catch exception Constraint_Error if Barrier = True
1422 Previously, it was possible to add a condition to such catchpoints,
1423 but it had to be done as a second step, after the catchpoint had been
1424 created, using the "condition" command.
1426 * The "info static-tracepoint-marker" command will now also work on
1427 native Linux targets with in-process agent.
1429 * GDB can now set breakpoints on inlined functions.
1431 * The .gdb_index section has been updated to include symbols for
1432 inlined functions. GDB will ignore older .gdb_index sections by
1433 default, which could cause symbol files to be loaded more slowly
1434 until their .gdb_index sections can be recreated. The new command
1435 "set use-deprecated-index-sections on" will cause GDB to use any older
1436 .gdb_index sections it finds. This will restore performance, but the
1437 ability to set breakpoints on inlined functions will be lost in symbol
1438 files with older .gdb_index sections.
1440 The .gdb_index section has also been updated to record more information
1441 about each symbol. This speeds up the "info variables", "info functions"
1442 and "info types" commands when used with programs having the .gdb_index
1443 section, as well as speeding up debugging with shared libraries using
1444 the .gdb_index section.
1446 * Ada support for GDB/MI Variable Objects has been added.
1448 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1453 ** New command -info-os is the MI equivalent of "info os".
1455 ** Output logs ("set logging" and related) now include MI output.
1459 ** "set use-deprecated-index-sections on|off"
1460 "show use-deprecated-index-sections on|off"
1461 Controls the use of deprecated .gdb_index sections.
1463 ** "catch load" and "catch unload" can be used to stop when a shared
1464 library is loaded or unloaded, respectively.
1466 ** "enable count" can be used to auto-disable a breakpoint after
1469 ** "info vtbl" can be used to show the virtual method tables for
1470 C++ and Java objects.
1472 ** "explore" and its sub commands "explore value" and "explore type"
1473 can be used to recursively explore values and types of
1474 expressions. These commands are available only if GDB is
1475 configured with '--with-python'.
1477 ** "info auto-load" shows status of all kinds of auto-loaded files,
1478 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1479 sequences of commands files, "info auto-load python-scripts"
1480 shows status of auto-loading Python script files,
1481 "info auto-load local-gdbinit" shows status of loading init file
1482 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1483 status of inferior specific thread debugging shared library loading.
1485 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1486 and "show auto-load-scripts" commands have been deprecated, use their
1487 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1488 and "show auto-load python-scripts" counterparts instead.
1490 ** "dprintf location,format,args..." creates a dynamic printf, which
1491 is basically a breakpoint that does a printf and immediately
1492 resumes your program's execution, so it is like a printf that you
1493 can insert dynamically at runtime instead of at compiletime.
1495 ** "set print symbol"
1497 Controls whether GDB attempts to display the symbol, if any,
1498 corresponding to addresses it prints. This defaults to "on", but
1499 you can set it to "off" to restore GDB's previous behavior.
1501 * Deprecated commands
1503 ** For the Renesas Super-H architecture, the "regs" command has been
1504 deprecated, and "info all-registers" should be used instead.
1508 Renesas RL78 rl78-*-elf
1509 HP OpenVMS ia64 ia64-hp-openvms*
1511 * GDBserver supports evaluation of breakpoint conditions. When
1512 support is advertised by GDBserver, GDB may be told to send the
1513 breakpoint conditions in bytecode form to GDBserver. GDBserver
1514 will only report the breakpoint trigger to GDB when its condition
1519 set mips compression
1520 show mips compression
1521 Select the compressed ISA encoding used in functions that have no symbol
1522 information available. The encoding can be set to either of:
1525 and is updated automatically from ELF file flags if available.
1527 set breakpoint condition-evaluation
1528 show breakpoint condition-evaluation
1529 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1530 GDBserver ("target"). Default option "auto" chooses the most efficient
1532 This option can improve debugger efficiency depending on the speed of the
1536 Disable auto-loading globally.
1539 Show auto-loading setting of all kinds of auto-loaded files.
1541 set auto-load gdb-scripts on|off
1542 show auto-load gdb-scripts
1543 Control auto-loading of GDB canned sequences of commands files.
1545 set auto-load python-scripts on|off
1546 show auto-load python-scripts
1547 Control auto-loading of Python script files.
1549 set auto-load local-gdbinit on|off
1550 show auto-load local-gdbinit
1551 Control loading of init file (.gdbinit) from current directory.
1553 set auto-load libthread-db on|off
1554 show auto-load libthread-db
1555 Control auto-loading of inferior specific thread debugging shared library.
1557 set auto-load scripts-directory <dir1>[:<dir2>...]
1558 show auto-load scripts-directory
1559 Set a list of directories from which to load auto-loaded scripts.
1560 Automatically loaded Python scripts and GDB scripts are located in one
1561 of the directories listed by this option.
1562 The delimiter (':' above) may differ according to the host platform.
1564 set auto-load safe-path <dir1>[:<dir2>...]
1565 show auto-load safe-path
1566 Set a list of directories from which it is safe to auto-load files.
1567 The delimiter (':' above) may differ according to the host platform.
1569 set debug auto-load on|off
1570 show debug auto-load
1571 Control display of debugging info for auto-loading the files above.
1573 set dprintf-style gdb|call|agent
1575 Control the way in which a dynamic printf is performed; "gdb"
1576 requests a GDB printf command, while "call" causes dprintf to call a
1577 function in the inferior. "agent" requests that the target agent
1578 (such as GDBserver) do the printing.
1580 set dprintf-function <expr>
1581 show dprintf-function
1582 set dprintf-channel <expr>
1583 show dprintf-channel
1584 Set the function and optional first argument to the call when using
1585 the "call" style of dynamic printf.
1587 set disconnected-dprintf on|off
1588 show disconnected-dprintf
1589 Control whether agent-style dynamic printfs continue to be in effect
1590 after GDB disconnects.
1592 * New configure options
1594 --with-auto-load-dir
1595 Configure default value for the 'set auto-load scripts-directory'
1596 setting above. It defaults to '$debugdir:$datadir/auto-load',
1597 $debugdir representing global debugging info directories (available
1598 via 'show debug-file-directory') and $datadir representing GDB's data
1599 directory (available via 'show data-directory').
1601 --with-auto-load-safe-path
1602 Configure default value for the 'set auto-load safe-path' setting
1603 above. It defaults to the --with-auto-load-dir setting.
1605 --without-auto-load-safe-path
1606 Set 'set auto-load safe-path' to '/', effectively disabling this
1609 * New remote packets
1611 z0/z1 conditional breakpoints extension
1613 The z0/z1 breakpoint insertion packets have been extended to carry
1614 a list of conditional expressions over to the remote stub depending on the
1615 condition evaluation mode. The use of this extension can be controlled
1616 via the "set remote conditional-breakpoints-packet" command.
1620 Specify the signals which the remote stub may pass to the debugged
1621 program without GDB involvement.
1623 * New command line options
1625 --init-command=FILE, -ix Like --command, -x but execute it
1626 before loading inferior.
1627 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1628 execute it before loading inferior.
1630 *** Changes in GDB 7.4
1632 * GDB now handles ambiguous linespecs more consistently; the existing
1633 FILE:LINE support has been expanded to other types of linespecs. A
1634 breakpoint will now be set on all matching locations in all
1635 inferiors, and locations will be added or removed according to
1638 * GDB now allows you to skip uninteresting functions and files when
1639 stepping with the "skip function" and "skip file" commands.
1641 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1642 and "show remote hardware-watchpoint-length-limit". These allows to
1643 set or show the maximum length limit (in bytes) of a remote
1644 target hardware watchpoint.
1646 This allows e.g. to use "unlimited" hardware watchpoints with the
1647 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1648 watchpoints are slower than real hardware watchpoints but are
1649 significantly faster than gdb software watchpoints.
1653 ** The register_pretty_printer function in module gdb.printing now takes
1654 an optional `replace' argument. If True, the new printer replaces any
1657 ** The "maint set python print-stack on|off" command has been
1658 deprecated and will be deleted in GDB 7.5.
1659 A new command: "set python print-stack none|full|message" has
1660 replaced it. Additionally, the default for "print-stack" is
1661 now "message", which just prints the error message without
1664 ** A prompt substitution hook (prompt_hook) is now available to the
1667 ** A new Python module, gdb.prompt has been added to the GDB Python
1668 modules library. This module provides functionality for
1669 escape sequences in prompts (used by set/show
1670 extended-prompt). These escape sequences are replaced by their
1671 corresponding value.
1673 ** Python commands and convenience-functions located in
1674 'data-directory'/python/gdb/command and
1675 'data-directory'/python/gdb/function are now automatically loaded
1678 ** Blocks now provide four new attributes. global_block and
1679 static_block will return the global and static blocks
1680 respectively. is_static and is_global are boolean attributes
1681 that indicate if the block is one of those two types.
1683 ** Symbols now provide the "type" attribute, the type of the symbol.
1685 ** The "gdb.breakpoint" function has been deprecated in favor of
1688 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1689 of a function. This class is based on the "finish" command
1690 available in the CLI.
1692 ** Type objects for struct and union types now allow access to
1693 the fields using standard Python dictionary (mapping) methods.
1694 For example, "some_type['myfield']" now works, as does
1695 "some_type.items()".
1697 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1700 ** A new function, "deep_items" has been added to the gdb.types
1701 module in the GDB Python modules library. This function returns
1702 an iterator over the fields of a struct or union type. Unlike
1703 the standard Python "iteritems" method, it will recursively traverse
1704 any anonymous fields.
1708 ** "*stopped" events can report several new "reason"s, such as
1711 ** Breakpoint changes are now notified using new async records, like
1712 "=breakpoint-modified".
1714 ** New command -ada-task-info.
1716 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1717 $sdir specifies the default system locations of shared libraries.
1718 $pdir specifies the directory where the libpthread used by the application
1721 GDB no longer looks in $sdir and $pdir after it has searched the directories
1722 mentioned in libthread-db-search-path. If you want to search those
1723 directories, they must be specified in libthread-db-search-path.
1724 The default value of libthread-db-search-path on GNU/Linux and Solaris
1725 systems is now "$sdir:$pdir".
1727 $pdir is not supported by gdbserver, it is currently ignored.
1728 $sdir is supported by gdbserver.
1730 * New configure option --with-iconv-bin.
1731 When using the internationalization support like the one in the GNU C
1732 library, GDB will invoke the "iconv" program to get a list of supported
1733 character sets. If this program lives in a non-standard location, one can
1734 use this option to specify where to find it.
1736 * When natively debugging programs on PowerPC BookE processors running
1737 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1738 watchpoints, which specify a mask in addition to an address to watch.
1739 The mask specifies that some bits of an address (the bits which are
1740 reset in the mask) should be ignored when matching the address accessed
1741 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1742 section in the user manual for more details.
1744 * The new option --once causes GDBserver to stop listening for connections once
1745 the first connection is made. The listening port used by GDBserver will
1746 become available after that.
1748 * New commands "info macros" and "alias" have been added.
1750 * New function parameters suffix @entry specifies value of function parameter
1751 at the time the function got called. Entry values are available only since
1757 "!" is now an alias of the "shell" command.
1758 Note that no space is needed between "!" and SHELL COMMAND.
1762 watch EXPRESSION mask MASK_VALUE
1763 The watch command now supports the mask argument which allows creation
1764 of masked watchpoints, if the current architecture supports this feature.
1766 info auto-load-scripts [REGEXP]
1767 This command was formerly named "maintenance print section-scripts".
1768 It is now generally useful and is no longer a maintenance-only command.
1770 info macro [-all] [--] MACRO
1771 The info macro command has new options `-all' and `--'. The first for
1772 printing all definitions of a macro. The second for explicitly specifying
1773 the end of arguments and the beginning of the macro name in case the macro
1774 name starts with a hyphen.
1776 collect[/s] EXPRESSIONS
1777 The tracepoint collect command now takes an optional modifier "/s"
1778 that directs it to dereference pointer-to-character types and
1779 collect the bytes of memory up to a zero byte. The behavior is
1780 similar to what you see when you use the regular print command on a
1781 string. An optional integer following the "/s" sets a bound on the
1782 number of bytes that will be collected.
1785 The trace start command now interprets any supplied arguments as a
1786 note to be recorded with the trace run, with an effect similar to
1787 setting the variable trace-notes.
1790 The trace stop command now interprets any arguments as a note to be
1791 mentioned along with the tstatus report that the trace was stopped
1792 with a command. The effect is similar to setting the variable
1795 * Tracepoints can now be enabled and disabled at any time after a trace
1796 experiment has been started using the standard "enable" and "disable"
1797 commands. It is now possible to start a trace experiment with no enabled
1798 tracepoints; GDB will display a warning, but will allow the experiment to
1799 begin, assuming that tracepoints will be enabled as needed while the trace
1802 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1803 locations with 4-byte instructions, when they were previously
1804 limited to locations with instructions of 5 bytes or longer.
1808 set debug dwarf2-read
1809 show debug dwarf2-read
1810 Turns on or off display of debugging messages related to reading
1811 DWARF debug info. The default is off.
1813 set debug symtab-create
1814 show debug symtab-create
1815 Turns on or off display of debugging messages related to symbol table
1816 creation. The default is off.
1819 show extended-prompt
1820 Set the GDB prompt, and allow escape sequences to be inserted to
1821 display miscellaneous information (see 'help set extended-prompt'
1822 for the list of sequences). This prompt (and any information
1823 accessed through the escape sequences) is updated every time the
1824 prompt is displayed.
1826 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1827 show print entry-values
1828 Set printing of frame argument values at function entry. In some cases
1829 GDB can determine the value of function argument which was passed by the
1830 function caller, even if the value was modified inside the called function.
1832 set debug entry-values
1833 show debug entry-values
1834 Control display of debugging info for determining frame argument values at
1835 function entry and virtual tail call frames.
1837 set basenames-may-differ
1838 show basenames-may-differ
1839 Set whether a source file may have multiple base names.
1840 (A "base name" is the name of a file with the directory part removed.
1841 Example: The base name of "/home/user/hello.c" is "hello.c".)
1842 If set, GDB will canonicalize file names (e.g., expand symlinks)
1843 before comparing them. Canonicalization is an expensive operation,
1844 but it allows the same file be known by more than one base name.
1845 If not set (the default), all source files are assumed to have just
1846 one base name, and gdb will do file name comparisons more efficiently.
1852 Set a user name and notes for the current and any future trace runs.
1853 This is useful for long-running and/or disconnected traces, to
1854 inform others (or yourself) as to who is running the trace, supply
1855 contact information, or otherwise explain what is going on.
1857 set trace-stop-notes
1858 show trace-stop-notes
1859 Set a note attached to the trace run, that is displayed when the
1860 trace has been stopped by a tstop command. This is useful for
1861 instance as an explanation, if you are stopping a trace run that was
1862 started by someone else.
1864 * New remote packets
1868 Dynamically enable a tracepoint in a started trace experiment.
1872 Dynamically disable a tracepoint in a started trace experiment.
1876 Set the user and notes of the trace run.
1880 Query the current status of a tracepoint.
1884 Query the minimum length of instruction at which a fast tracepoint may
1887 * Dcache size (number of lines) and line-size are now runtime-configurable
1888 via "set dcache line" and "set dcache line-size" commands.
1892 Texas Instruments TMS320C6x tic6x-*-*
1896 Renesas RL78 rl78-*-elf
1898 *** Changes in GDB 7.3.1
1900 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1902 *** Changes in GDB 7.3
1904 * GDB has a new command: "thread find [REGEXP]".
1905 It finds the thread id whose name, target id, or thread extra info
1906 matches the given regular expression.
1908 * The "catch syscall" command now works on mips*-linux* targets.
1910 * The -data-disassemble MI command now supports modes 2 and 3 for
1911 dumping the instruction opcodes.
1913 * New command line options
1915 -data-directory DIR Specify DIR as the "data-directory".
1916 This is mostly for testing purposes.
1918 * The "maint set python auto-load on|off" command has been renamed to
1919 "set auto-load-scripts on|off".
1921 * GDB has a new command: "set directories".
1922 It is like the "dir" command except that it replaces the
1923 source path list instead of augmenting it.
1925 * GDB now understands thread names.
1927 On GNU/Linux, "info threads" will display the thread name as set by
1928 prctl or pthread_setname_np.
1930 There is also a new command, "thread name", which can be used to
1931 assign a name internally for GDB to display.
1934 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1935 has been integrated into GDB.
1939 ** The function gdb.Write now accepts an optional keyword 'stream'.
1940 This keyword, when provided, will direct the output to either
1941 stdout, stderr, or GDB's logging output.
1943 ** Parameters can now be be sub-classed in Python, and in particular
1944 you may implement the get_set_doc and get_show_doc functions.
1945 This improves how Parameter set/show documentation is processed
1946 and allows for more dynamic content.
1948 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1949 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1950 have an is_valid method.
1952 ** Breakpoints can now be sub-classed in Python, and in particular
1953 you may implement a 'stop' function that is executed each time
1954 the inferior reaches that breakpoint.
1956 ** New function gdb.lookup_global_symbol looks up a global symbol.
1958 ** GDB values in Python are now callable if the value represents a
1959 function. For example, if 'some_value' represents a function that
1960 takes two integer parameters and returns a value, you can call
1961 that function like so:
1963 result = some_value (10,20)
1965 ** Module gdb.types has been added.
1966 It contains a collection of utilities for working with gdb.Types objects:
1967 get_basic_type, has_field, make_enum_dict.
1969 ** Module gdb.printing has been added.
1970 It contains utilities for writing and registering pretty-printers.
1971 New classes: PrettyPrinter, SubPrettyPrinter,
1972 RegexpCollectionPrettyPrinter.
1973 New function: register_pretty_printer.
1975 ** New commands "info pretty-printers", "enable pretty-printer" and
1976 "disable pretty-printer" have been added.
1978 ** gdb.parameter("directories") is now available.
1980 ** New function gdb.newest_frame returns the newest frame in the
1983 ** The gdb.InferiorThread class has a new "name" attribute. This
1984 holds the thread's name.
1986 ** Python Support for Inferior events.
1987 Python scripts can add observers to be notified of events
1988 occurring in the process being debugged.
1989 The following events are currently supported:
1990 - gdb.events.cont Continue event.
1991 - gdb.events.exited Inferior exited event.
1992 - gdb.events.stop Signal received, and Breakpoint hit events.
1996 ** GDB now puts template parameters in scope when debugging in an
1997 instantiation. For example, if you have:
1999 template<int X> int func (void) { return X; }
2001 then if you step into func<5>, "print X" will show "5". This
2002 feature requires proper debuginfo support from the compiler; it
2003 was added to GCC 4.5.
2005 ** The motion commands "next", "finish", "until", and "advance" now
2006 work better when exceptions are thrown. In particular, GDB will
2007 no longer lose control of the inferior; instead, the GDB will
2008 stop the inferior at the point at which the exception is caught.
2009 This functionality requires a change in the exception handling
2010 code that was introduced in GCC 4.5.
2012 * GDB now follows GCC's rules on accessing volatile objects when
2013 reading or writing target state during expression evaluation.
2014 One notable difference to prior behavior is that "print x = 0"
2015 no longer generates a read of x; the value of the assignment is
2016 now always taken directly from the value being assigned.
2018 * GDB now has some support for using labels in the program's source in
2019 linespecs. For instance, you can use "advance label" to continue
2020 execution to a label.
2022 * GDB now has support for reading and writing a new .gdb_index
2023 section. This section holds a fast index of DWARF debugging
2024 information and can be used to greatly speed up GDB startup and
2025 operation. See the documentation for `save gdb-index' for details.
2027 * The "watch" command now accepts an optional "-location" argument.
2028 When used, this causes GDB to watch the memory referred to by the
2029 expression. Such a watchpoint is never deleted due to it going out
2032 * GDB now supports thread debugging of core dumps on GNU/Linux.
2034 GDB now activates thread debugging using the libthread_db library
2035 when debugging GNU/Linux core dumps, similarly to when debugging
2036 live processes. As a result, when debugging a core dump file, GDB
2037 is now able to display pthread_t ids of threads. For example, "info
2038 threads" shows the same output as when debugging the process when it
2039 was live. In earlier releases, you'd see something like this:
2042 * 1 LWP 6780 main () at main.c:10
2044 While now you see this:
2047 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2049 It is also now possible to inspect TLS variables when debugging core
2052 When debugging a core dump generated on a machine other than the one
2053 used to run GDB, you may need to point GDB at the correct
2054 libthread_db library with the "set libthread-db-search-path"
2055 command. See the user manual for more details on this command.
2057 * When natively debugging programs on PowerPC BookE processors running
2058 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2059 which stop execution of the inferior whenever it executes an instruction
2060 at any address within the specified range. See the "PowerPC Embedded"
2061 section in the user manual for more details.
2063 * New features in the GDB remote stub, GDBserver
2065 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2066 and i686 LynxOS (version 5.x).
2068 ** GDBserver is now supported on Blackfin Linux.
2070 * New native configurations
2072 ia64 HP-UX ia64-*-hpux*
2076 Analog Devices, Inc. Blackfin Processor bfin-*
2078 * Ada task switching is now supported on sparc-elf targets when
2079 debugging a program using the Ravenscar Profile. For more information,
2080 see the "Tasking Support when using the Ravenscar Profile" section
2081 in the GDB user manual.
2083 * Guile support was removed.
2085 * New features in the GNU simulator
2087 ** The --map-info flag lists all known core mappings.
2089 ** CFI flashes may be simulated via the "cfi" device.
2091 *** Changes in GDB 7.2
2093 * Shared library support for remote targets by default
2095 When GDB is configured for a generic, non-OS specific target, like
2096 for example, --target=arm-eabi or one of the many *-*-elf targets,
2097 GDB now queries remote stubs for loaded shared libraries using the
2098 `qXfer:libraries:read' packet. Previously, shared library support
2099 was always disabled for such configurations.
2103 ** Argument Dependent Lookup (ADL)
2105 In C++ ADL lookup directs function search to the namespaces of its
2106 arguments even if the namespace has not been imported.
2116 Here the compiler will search for `foo' in the namespace of 'b'
2117 and find A::foo. GDB now supports this. This construct is commonly
2118 used in the Standard Template Library for operators.
2120 ** Improved User Defined Operator Support
2122 In addition to member operators, GDB now supports lookup of operators
2123 defined in a namespace and imported with a `using' directive, operators
2124 defined in the global scope, operators imported implicitly from an
2125 anonymous namespace, and the ADL operators mentioned in the previous
2127 GDB now also supports proper overload resolution for all the previously
2128 mentioned flavors of operators.
2130 ** static const class members
2132 Printing of static const class members that are initialized in the
2133 class definition has been fixed.
2135 * Windows Thread Information Block access.
2137 On Windows targets, GDB now supports displaying the Windows Thread
2138 Information Block (TIB) structure. This structure is visible either
2139 by using the new command `info w32 thread-information-block' or, by
2140 dereferencing the new convenience variable named `$_tlb', a
2141 thread-specific pointer to the TIB. This feature is also supported
2142 when remote debugging using GDBserver.
2144 * Static tracepoints
2146 Static tracepoints are calls in the user program into a tracing
2147 library. One such library is a port of the LTTng kernel tracer to
2148 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2149 When debugging with GDBserver, GDB now supports combining the GDB
2150 tracepoint machinery with such libraries. For example: the user can
2151 use GDB to probe a static tracepoint marker (a call from the user
2152 program into the tracing library) with the new "strace" command (see
2153 "New commands" below). This creates a "static tracepoint" in the
2154 breakpoint list, that can be manipulated with the same feature set
2155 as fast and regular tracepoints. E.g., collect registers, local and
2156 global variables, collect trace state variables, and define
2157 tracepoint conditions. In addition, the user can collect extra
2158 static tracepoint marker specific data, by collecting the new
2159 $_sdata internal variable. When analyzing the trace buffer, you can
2160 inspect $_sdata like any other variable available to GDB. For more
2161 information, see the "Tracepoints" chapter in GDB user manual. New
2162 remote packets have been defined to support static tracepoints, see
2163 the "New remote packets" section below.
2165 * Better reconstruction of tracepoints after disconnected tracing
2167 GDB will attempt to download the original source form of tracepoint
2168 definitions when starting a trace run, and then will upload these
2169 upon reconnection to the target, resulting in a more accurate
2170 reconstruction of the tracepoints that are in use on the target.
2174 You can now exercise direct control over the ways that GDB can
2175 affect your program. For instance, you can disallow the setting of
2176 breakpoints, so that the program can run continuously (assuming
2177 non-stop mode). In addition, the "observer" variable is available
2178 to switch all of the different controls; in observer mode, GDB
2179 cannot affect the target's behavior at all, which is useful for
2180 tasks like diagnosing live systems in the field.
2182 * The new convenience variable $_thread holds the number of the
2185 * New remote packets
2189 Return the address of the Windows Thread Information Block of a given thread.
2193 In response to several of the tracepoint packets, the target may now
2194 also respond with a number of intermediate `qRelocInsn' request
2195 packets before the final result packet, to have GDB handle
2196 relocating an instruction to execute at a different address. This
2197 is particularly useful for stubs that support fast tracepoints. GDB
2198 reports support for this feature in the qSupported packet.
2202 List static tracepoint markers in the target program.
2206 List static tracepoint markers at a given address in the target
2209 qXfer:statictrace:read
2211 Read the static trace data collected (by a `collect $_sdata'
2212 tracepoint action). The remote stub reports support for this packet
2213 to gdb's qSupported query.
2217 Send the current settings of GDB's permission flags.
2221 Send part of the source (textual) form of a tracepoint definition,
2222 which includes location, conditional, and action list.
2224 * The source command now accepts a -s option to force searching for the
2225 script in the source search path even if the script name specifies
2228 * New features in the GDB remote stub, GDBserver
2230 - GDBserver now support tracepoints (including fast tracepoints, and
2231 static tracepoints). The feature is currently supported by the
2232 i386-linux and amd64-linux builds. See the "Tracepoints support
2233 in gdbserver" section in the manual for more information.
2235 GDBserver JIT compiles the tracepoint's conditional agent
2236 expression bytecode into native code whenever possible for low
2237 overhead dynamic tracepoints conditionals. For such tracepoints,
2238 an expression that examines program state is evaluated when the
2239 tracepoint is reached, in order to determine whether to capture
2240 trace data. If the condition is simple and false, processing the
2241 tracepoint finishes very quickly and no data is gathered.
2243 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2244 for static tracepoints support.
2246 - GDBserver now supports x86_64 Windows 64-bit debugging.
2248 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2249 it understands register description.
2251 * The --batch flag now disables pagination and queries.
2253 * X86 general purpose registers
2255 GDB now supports reading/writing byte, word and double-word x86
2256 general purpose registers directly. This means you can use, say,
2257 $ah or $ax to refer, respectively, to the byte register AH and
2258 16-bit word register AX that are actually portions of the 32-bit
2259 register EAX or 64-bit register RAX.
2261 * The `commands' command now accepts a range of breakpoints to modify.
2262 A plain `commands' following a command that creates multiple
2263 breakpoints affects all the breakpoints set by that command. This
2264 applies to breakpoints set by `rbreak', and also applies when a
2265 single `break' command creates multiple breakpoints (e.g.,
2266 breakpoints on overloaded c++ functions).
2268 * The `rbreak' command now accepts a filename specification as part of
2269 its argument, limiting the functions selected by the regex to those
2270 in the specified file.
2272 * Support for remote debugging Windows and SymbianOS shared libraries
2273 from Unix hosts has been improved. Non Windows GDB builds now can
2274 understand target reported file names that follow MS-DOS based file
2275 system semantics, such as file names that include drive letters and
2276 use the backslash character as directory separator. This makes it
2277 possible to transparently use the "set sysroot" and "set
2278 solib-search-path" on Unix hosts to point as host copies of the
2279 target's shared libraries. See the new command "set
2280 target-file-system-kind" described below, and the "Commands to
2281 specify files" section in the user manual for more information.
2285 eval template, expressions...
2286 Convert the values of one or more expressions under the control
2287 of the string template to a command line, and call it.
2289 set target-file-system-kind unix|dos-based|auto
2290 show target-file-system-kind
2291 Set or show the assumed file system kind for target reported file
2294 save breakpoints <filename>
2295 Save all current breakpoint definitions to a file suitable for use
2296 in a later debugging session. To read the saved breakpoint
2297 definitions, use the `source' command.
2299 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2302 info static-tracepoint-markers
2303 Display information about static tracepoint markers in the target.
2305 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2306 Define a static tracepoint by probing a marker at the given
2307 function, line, address, or marker ID.
2311 Enable and disable observer mode.
2313 set may-write-registers on|off
2314 set may-write-memory on|off
2315 set may-insert-breakpoints on|off
2316 set may-insert-tracepoints on|off
2317 set may-insert-fast-tracepoints on|off
2318 set may-interrupt on|off
2319 Set individual permissions for GDB effects on the target. Note that
2320 some of these settings can have undesirable or surprising
2321 consequences, particularly when changed in the middle of a session.
2322 For instance, disabling the writing of memory can prevent
2323 breakpoints from being inserted, cause single-stepping to fail, or
2324 even crash your program, if you disable after breakpoints have been
2325 inserted. However, GDB should not crash.
2327 set record memory-query on|off
2328 show record memory-query
2329 Control whether to stop the inferior if memory changes caused
2330 by an instruction cannot be recorded.
2335 The disassemble command now supports "start,+length" form of two arguments.
2339 ** GDB now provides a new directory location, called the python directory,
2340 where Python scripts written for GDB can be installed. The location
2341 of that directory is <data-directory>/python, where <data-directory>
2342 is the GDB data directory. For more details, see section `Scripting
2343 GDB using Python' in the manual.
2345 ** The GDB Python API now has access to breakpoints, symbols, symbol
2346 tables, program spaces, inferiors, threads and frame's code blocks.
2347 Additionally, GDB Parameters can now be created from the API, and
2348 manipulated via set/show in the CLI.
2350 ** New functions gdb.target_charset, gdb.target_wide_charset,
2351 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2353 ** New exception gdb.GdbError.
2355 ** Pretty-printers are now also looked up in the current program space.
2357 ** Pretty-printers can now be individually enabled and disabled.
2359 ** GDB now looks for names of Python scripts to auto-load in a
2360 special section named `.debug_gdb_scripts', in addition to looking
2361 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2363 * Tracepoint actions were unified with breakpoint commands. In particular,
2364 there are no longer differences in "info break" output for breakpoints and
2365 tracepoints and the "commands" command can be used for both tracepoints and
2366 regular breakpoints.
2370 ARM Symbian arm*-*-symbianelf*
2372 * D language support.
2373 GDB now supports debugging programs written in the D programming
2376 * GDB now supports the extended ptrace interface for PowerPC which is
2377 available since Linux kernel version 2.6.34. This automatically enables
2378 any hardware breakpoints and additional hardware watchpoints available in
2379 the processor. The old ptrace interface exposes just one hardware
2380 watchpoint and no hardware breakpoints.
2382 * GDB is now able to use the Data Value Compare (DVC) register available on
2383 embedded PowerPC processors to implement in hardware simple watchpoint
2384 conditions of the form:
2386 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2388 This works in native GDB running on Linux kernels with the extended ptrace
2389 interface mentioned above.
2391 *** Changes in GDB 7.1
2395 ** Namespace Support
2397 GDB now supports importing of namespaces in C++. This enables the
2398 user to inspect variables from imported namespaces. Support for
2399 namepace aliasing has also been added. So, if a namespace is
2400 aliased in the current scope (e.g. namepace C=A; ) the user can
2401 print variables using the alias (e.g. (gdb) print C::x).
2405 All known bugs relating to the printing of virtual base class were
2406 fixed. It is now possible to call overloaded static methods using a
2411 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2412 and reinterpret_cast<> are now handled by the C++ expression parser.
2416 Xilinx MicroBlaze microblaze-*-*
2421 Xilinx MicroBlaze microblaze
2424 * Multi-program debugging.
2426 GDB now has support for multi-program (a.k.a. multi-executable or
2427 multi-exec) debugging. This allows for debugging multiple inferiors
2428 simultaneously each running a different program under the same GDB
2429 session. See "Debugging Multiple Inferiors and Programs" in the
2430 manual for more information. This implied some user visible changes
2431 in the multi-inferior support. For example, "info inferiors" now
2432 lists inferiors that are not running yet or that have exited
2433 already. See also "New commands" and "New options" below.
2435 * New tracing features
2437 GDB's tracepoint facility now includes several new features:
2439 ** Trace state variables
2441 GDB tracepoints now include support for trace state variables, which
2442 are variables managed by the target agent during a tracing
2443 experiment. They are useful for tracepoints that trigger each
2444 other, so for instance one tracepoint can count hits in a variable,
2445 and then a second tracepoint has a condition that is true when the
2446 count reaches a particular value. Trace state variables share the
2447 $-syntax of GDB convenience variables, and can appear in both
2448 tracepoint actions and condition expressions. Use the "tvariable"
2449 command to create, and "info tvariables" to view; see "Trace State
2450 Variables" in the manual for more detail.
2454 GDB now includes an option for defining fast tracepoints, which
2455 targets may implement more efficiently, such as by installing a jump
2456 into the target agent rather than a trap instruction. The resulting
2457 speedup can be by two orders of magnitude or more, although the
2458 tradeoff is that some program locations on some target architectures
2459 might not allow fast tracepoint installation, for instance if the
2460 instruction to be replaced is shorter than the jump. To request a
2461 fast tracepoint, use the "ftrace" command, with syntax identical to
2462 the regular trace command.
2464 ** Disconnected tracing
2466 It is now possible to detach GDB from the target while it is running
2467 a trace experiment, then reconnect later to see how the experiment
2468 is going. In addition, a new variable disconnected-tracing lets you
2469 tell the target agent whether to continue running a trace if the
2470 connection is lost unexpectedly.
2474 GDB now has the ability to save the trace buffer into a file, and
2475 then use that file as a target, similarly to you can do with
2476 corefiles. You can select trace frames, print data that was
2477 collected in them, and use tstatus to display the state of the
2478 tracing run at the moment that it was saved. To create a trace
2479 file, use "tsave <filename>", and to use it, do "target tfile
2482 ** Circular trace buffer
2484 You can ask the target agent to handle the trace buffer as a
2485 circular buffer, discarding the oldest trace frames to make room for
2486 newer ones, by setting circular-trace-buffer to on. This feature may
2487 not be available for all target agents.
2492 The disassemble command, when invoked with two arguments, now requires
2493 the arguments to be comma-separated.
2496 The info variables command now displays variable definitions. Files
2497 which only declare a variable are not shown.
2500 The source command is now capable of sourcing Python scripts.
2501 This feature is dependent on the debugger being build with Python
2504 Related to this enhancement is also the introduction of a new command
2505 "set script-extension" (see below).
2507 * New commands (for set/show, see "New options" below)
2509 record save [<FILENAME>]
2510 Save a file (in core file format) containing the process record
2511 execution log for replay debugging at a later time.
2513 record restore <FILENAME>
2514 Restore the process record execution log that was saved at an
2515 earlier time, for replay debugging.
2517 add-inferior [-copies <N>] [-exec <FILENAME>]
2520 clone-inferior [-copies <N>] [ID]
2521 Make a new inferior ready to execute the same program another
2522 inferior has loaded.
2527 maint info program-spaces
2528 List the program spaces loaded into GDB.
2530 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2531 show remote interrupt-sequence
2532 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2533 as the sequence to the remote target in order to interrupt the execution.
2534 Ctrl-C is a default. Some system prefers BREAK which is high level of
2535 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2536 Magic SysRq g. It is BREAK signal and character 'g'.
2538 set remote interrupt-on-connect [on | off]
2539 show remote interrupt-on-connect
2540 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2541 remote target when gdb connects to it. This is needed when you debug
2544 set remotebreak [on | off]
2546 Deprecated. Use "set/show remote interrupt-sequence" instead.
2548 tvariable $NAME [ = EXP ]
2549 Create or modify a trace state variable.
2552 List trace state variables and their values.
2554 delete tvariable $NAME ...
2555 Delete one or more trace state variables.
2558 Evaluate the given expressions without collecting anything into the
2559 trace buffer. (Valid in tracepoint actions only.)
2561 ftrace FN / FILE:LINE / *ADDR
2562 Define a fast tracepoint at the given function, line, or address.
2564 * New expression syntax
2566 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2567 GDB now parses 0b101010 identically with 42.
2571 set follow-exec-mode new|same
2572 show follow-exec-mode
2573 Control whether GDB reuses the same inferior across an exec call or
2574 creates a new one. This is useful to be able to restart the old
2575 executable after the inferior having done an exec call.
2577 set default-collect EXPR, ...
2578 show default-collect
2579 Define a list of expressions to be collected at each tracepoint.
2580 This is a useful way to ensure essential items are not overlooked,
2581 such as registers or a critical global variable.
2583 set disconnected-tracing
2584 show disconnected-tracing
2585 If set to 1, the target is instructed to continue tracing if it
2586 loses its connection to GDB. If 0, the target is to stop tracing
2589 set circular-trace-buffer
2590 show circular-trace-buffer
2591 If set to on, the target is instructed to use a circular trace buffer
2592 and discard the oldest trace frames instead of stopping the trace due
2593 to a full trace buffer. If set to off, the trace stops when the buffer
2594 fills up. Some targets may not support this.
2596 set script-extension off|soft|strict
2597 show script-extension
2598 If set to "off", the debugger does not perform any script language
2599 recognition, and all sourced files are assumed to be GDB scripts.
2600 If set to "soft" (the default), files are sourced according to
2601 filename extension, falling back to GDB scripts if the first
2603 If set to "strict", files are sourced according to filename extension.
2605 set ada trust-PAD-over-XVS on|off
2606 show ada trust-PAD-over-XVS
2607 If off, activate a workaround against a bug in the debugging information
2608 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2609 the GCC sources for more information about the GNAT encoding and
2610 PAD types in particular). It is always safe to set this option to
2611 off, but this introduces a slight performance penalty. The default
2614 * Python API Improvements
2616 ** GDB provides the new class gdb.LazyString. This is useful in
2617 some pretty-printing cases. The new method gdb.Value.lazy_string
2618 provides a simple way to create objects of this type.
2620 ** The fields returned by gdb.Type.fields now have an
2621 `is_base_class' attribute.
2623 ** The new method gdb.Type.range returns the range of an array type.
2625 ** The new method gdb.parse_and_eval can be used to parse and
2626 evaluate an expression.
2628 * New remote packets
2631 Define a trace state variable.
2634 Get the current value of a trace state variable.
2637 Set desired tracing behavior upon disconnection.
2640 Set the trace buffer to be linear or circular.
2643 Get data about the tracepoints currently in use.
2647 Process record now works correctly with hardware watchpoints.
2649 Multiple bug fixes have been made to the mips-irix port, making it
2650 much more reliable. In particular:
2651 - Debugging threaded applications is now possible again. Previously,
2652 GDB would hang while starting the program, or while waiting for
2653 the program to stop at a breakpoint.
2654 - Attaching to a running process no longer hangs.
2655 - An error occurring while loading a core file has been fixed.
2656 - Changing the value of the PC register now works again. This fixes
2657 problems observed when using the "jump" command, or when calling
2658 a function from GDB, or even when assigning a new value to $pc.
2659 - With the "finish" and "return" commands, the return value for functions
2660 returning a small array is now correctly printed.
2661 - It is now possible to break on shared library code which gets executed
2662 during a shared library init phase (code executed while executing
2663 their .init section). Previously, the breakpoint would have no effect.
2664 - GDB is now able to backtrace through the signal handler for
2665 non-threaded programs.
2667 PIE (Position Independent Executable) programs debugging is now supported.
2668 This includes debugging execution of PIC (Position Independent Code) shared
2669 libraries although for that, it should be possible to run such libraries as an
2672 *** Changes in GDB 7.0
2674 * GDB now has an interface for JIT compilation. Applications that
2675 dynamically generate code can create symbol files in memory and register
2676 them with GDB. For users, the feature should work transparently, and
2677 for JIT developers, the interface is documented in the GDB manual in the
2678 "JIT Compilation Interface" chapter.
2680 * Tracepoints may now be conditional. The syntax is as for
2681 breakpoints; either an "if" clause appended to the "trace" command,
2682 or the "condition" command is available. GDB sends the condition to
2683 the target for evaluation using the same bytecode format as is used
2684 for tracepoint actions.
2686 * The disassemble command now supports: an optional /r modifier, print the
2687 raw instructions in hex as well as in symbolic form, and an optional /m
2688 modifier to print mixed source+assembly.
2690 * Process record and replay
2692 In a architecture environment that supports ``process record and
2693 replay'', ``process record and replay'' target can record a log of
2694 the process execution, and replay it with both forward and reverse
2697 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2698 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2699 set execution-direction {forward|reverse}, for targets that support
2702 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2703 feature is available with a native GDB running on kernel version
2706 * GDB now has support for multi-byte and wide character sets on the
2707 target. Strings whose character type is wchar_t, char16_t, or
2708 char32_t are now correctly printed. GDB supports wide- and unicode-
2709 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2710 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2711 `printf'. This feature requires iconv to work properly; if your
2712 system does not have a working iconv, GDB can use GNU libiconv. See
2713 the installation instructions for more information.
2715 * GDB now supports automatic retrieval of shared library files from
2716 remote targets. To use this feature, specify a system root that begins
2717 with the `remote:' prefix, either via the `set sysroot' command or via
2718 the `--with-sysroot' configure-time option.
2720 * "info sharedlibrary" now takes an optional regex of libraries to show,
2721 and it now reports if a shared library has no debugging information.
2723 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2724 now complete on file names.
2726 * When completing in expressions, gdb will attempt to limit
2727 completions to allowable structure or union fields, where appropriate.
2728 For instance, consider:
2730 # struct example { int f1; double f2; };
2731 # struct example variable;
2734 If the user types TAB at the end of this command line, the available
2735 completions will be "f1" and "f2".
2737 * Inlined functions are now supported. They show up in backtraces, and
2738 the "step", "next", and "finish" commands handle them automatically.
2740 * GDB now supports the token-splicing (##) and stringification (#)
2741 operators when expanding macros. It also supports variable-arity
2744 * GDB now supports inspecting extra signal information, exported by
2745 the new $_siginfo convenience variable. The feature is currently
2746 implemented on linux ARM, i386 and amd64.
2748 * GDB can now display the VFP floating point registers and NEON vector
2749 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2750 can provide these registers (requires Linux 2.6.30 or later). Remote
2751 and simulator targets may also provide them.
2753 * New remote packets
2756 Search memory for a sequence of bytes.
2759 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2760 operation over reliable transport links. Use of this packet is
2761 controlled by the `set remote noack-packet' command.
2764 Kill the process with the specified process ID. Use this in preference
2765 to `k' when multiprocess protocol extensions are supported.
2768 Obtains additional operating system information
2772 Read or write additional signal information.
2774 * Removed remote protocol undocumented extension
2776 An undocumented extension to the remote protocol's `S' stop reply
2777 packet that permited the stub to pass a process id was removed.
2778 Remote servers should use the `T' stop reply packet instead.
2780 * GDB now supports multiple function calling conventions according to the
2781 DWARF-2 DW_AT_calling_convention function attribute.
2783 * The SH target utilizes the aforementioned change to distinguish between gcc
2784 and Renesas calling convention. It also adds the new CLI commands
2785 `set/show sh calling-convention'.
2787 * GDB can now read compressed debug sections, as produced by GNU gold
2788 with the --compress-debug-sections=zlib flag.
2790 * 64-bit core files are now supported on AIX.
2792 * Thread switching is now supported on Tru64.
2794 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2795 which will be allocated using malloc later in program execution.
2797 * The qXfer:libraries:read remote procotol packet now allows passing a
2798 list of section offsets.
2800 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2801 conditions handling signals delivered during attach or thread creation
2802 have also been fixed.
2804 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2805 From the user's standpoint, all unqualified instances of True and False
2806 are treated as the standard definitions, regardless of context.
2808 * GDB now parses C++ symbol and type names more flexibly. For
2811 template<typename T> class C { };
2814 GDB will now correctly handle all of:
2816 ptype C<char const *>
2817 ptype C<char const*>
2818 ptype C<const char *>
2819 ptype C<const char*>
2821 * New features in the GDB remote stub, gdbserver
2823 - The "--wrapper" command-line argument tells gdbserver to use a
2824 wrapper program to launch programs for debugging.
2826 - On PowerPC and S/390 targets, it is now possible to use a single
2827 gdbserver executable to debug both 32-bit and 64-bit programs.
2828 (This requires gdbserver itself to be built as a 64-bit executable.)
2830 - gdbserver uses the new noack protocol mode for TCP connections to
2831 reduce communications latency, if also supported and enabled in GDB.
2833 - Support for the sparc64-linux-gnu target is now included in
2836 - The amd64-linux build of gdbserver now supports debugging both
2837 32-bit and 64-bit programs.
2839 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2840 now support hardware watchpoints, and will use them automatically
2845 GDB now has support for scripting using Python. Whether this is
2846 available is determined at configure time.
2848 New GDB commands can now be written in Python.
2850 * Ada tasking support
2852 Ada tasks can now be inspected in GDB. The following commands have
2856 Print the list of Ada tasks.
2858 Print detailed information about task number N.
2860 Print the task number of the current task.
2862 Switch the context of debugging to task number N.
2864 * Support for user-defined prefixed commands. The "define" command can
2865 add new commands to existing prefixes, e.g. "target".
2867 * Multi-inferior, multi-process debugging.
2869 GDB now has generalized support for multi-inferior debugging. See
2870 "Debugging Multiple Inferiors" in the manual for more information.
2871 Although availability still depends on target support, the command
2872 set is more uniform now. The GNU/Linux specific multi-forks support
2873 has been migrated to this new framework. This implied some user
2874 visible changes; see "New commands" and also "Removed commands"
2877 * Target descriptions can now describe the target OS ABI. See the
2878 "Target Description Format" section in the user manual for more
2881 * Target descriptions can now describe "compatible" architectures
2882 to indicate that the target can execute applications for a different
2883 architecture in addition to those for the main target architecture.
2884 See the "Target Description Format" section in the user manual for
2887 * Multi-architecture debugging.
2889 GDB now includes general supports for debugging applications on
2890 hybrid systems that use more than one single processor architecture
2891 at the same time. Each such hybrid architecture still requires
2892 specific support to be added. The only hybrid architecture supported
2893 in this version of GDB is the Cell Broadband Engine.
2895 * GDB now supports integrated debugging of Cell/B.E. applications that
2896 use both the PPU and SPU architectures. To enable support for hybrid
2897 Cell/B.E. debugging, you need to configure GDB to support both the
2898 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2899 --enable-targets configure option.
2901 * Non-stop mode debugging.
2903 For some targets, GDB now supports an optional mode of operation in
2904 which you can examine stopped threads while other threads continue
2905 to execute freely. This is referred to as non-stop mode, with the
2906 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2907 section in the user manual for more information.
2909 To be able to support remote non-stop debugging, a remote stub needs
2910 to implement the non-stop mode remote protocol extensions, as
2911 described in the "Remote Non-Stop" section of the user manual. The
2912 GDB remote stub, gdbserver, has been adjusted to support these
2913 extensions on linux targets.
2915 * New commands (for set/show, see "New options" below)
2917 catch syscall [NAME(S) | NUMBER(S)]
2918 Catch system calls. Arguments, which should be names of system
2919 calls or their numbers, mean catch only those syscalls. Without
2920 arguments, every syscall will be caught. When the inferior issues
2921 any of the specified syscalls, GDB will stop and announce the system
2922 call, both when it is called and when its call returns. This
2923 feature is currently available with a native GDB running on the
2924 Linux Kernel, under the following architectures: x86, x86_64,
2925 PowerPC and PowerPC64.
2927 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2929 Search memory for a sequence of bytes.
2931 maint set python print-stack
2932 maint show python print-stack
2933 Show a stack trace when an error is encountered in a Python script.
2936 Invoke CODE by passing it to the Python interpreter.
2941 These allow macros to be defined, undefined, and listed
2945 Show operating system information about processes.
2948 List the inferiors currently under GDB's control.
2951 Switch focus to inferior number NUM.
2954 Detach from inferior number NUM.
2957 Kill inferior number NUM.
2961 set spu stop-on-load
2962 show spu stop-on-load
2963 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2965 set spu auto-flush-cache
2966 show spu auto-flush-cache
2967 Control whether to automatically flush the software-managed cache
2968 during Cell/B.E. debugging.
2970 set sh calling-convention
2971 show sh calling-convention
2972 Control the calling convention used when calling SH target functions.
2975 show debug timestamp
2976 Control display of timestamps with GDB debugging output.
2978 set disassemble-next-line
2979 show disassemble-next-line
2980 Control display of disassembled source lines or instructions when
2983 set remote noack-packet
2984 show remote noack-packet
2985 Set/show the use of remote protocol QStartNoAckMode packet. See above
2986 under "New remote packets."
2988 set remote query-attached-packet
2989 show remote query-attached-packet
2990 Control use of remote protocol `qAttached' (query-attached) packet.
2992 set remote read-siginfo-object
2993 show remote read-siginfo-object
2994 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2997 set remote write-siginfo-object
2998 show remote write-siginfo-object
2999 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3002 set remote reverse-continue
3003 show remote reverse-continue
3004 Control use of remote protocol 'bc' (reverse-continue) packet.
3006 set remote reverse-step
3007 show remote reverse-step
3008 Control use of remote protocol 'bs' (reverse-step) packet.
3010 set displaced-stepping
3011 show displaced-stepping
3012 Control displaced stepping mode. Displaced stepping is a way to
3013 single-step over breakpoints without removing them from the debuggee.
3014 Also known as "out-of-line single-stepping".
3017 show debug displaced
3018 Control display of debugging info for displaced stepping.
3020 maint set internal-error
3021 maint show internal-error
3022 Control what GDB does when an internal error is detected.
3024 maint set internal-warning
3025 maint show internal-warning
3026 Control what GDB does when an internal warning is detected.
3031 Use a wrapper program to launch programs for debugging.
3033 set multiple-symbols (all|ask|cancel)
3034 show multiple-symbols
3035 The value of this variable can be changed to adjust the debugger behavior
3036 when an expression or a breakpoint location contains an ambiguous symbol
3037 name (an overloaded function name, for instance).
3039 set breakpoint always-inserted
3040 show breakpoint always-inserted
3041 Keep breakpoints always inserted in the target, as opposed to inserting
3042 them when resuming the target, and removing them when the target stops.
3043 This option can improve debugger performance on slow remote targets.
3045 set arm fallback-mode (arm|thumb|auto)
3046 show arm fallback-mode
3047 set arm force-mode (arm|thumb|auto)
3049 These commands control how ARM GDB determines whether instructions
3050 are ARM or Thumb. The default for both settings is auto, which uses
3051 the current CPSR value for instructions without symbols; previous
3052 versions of GDB behaved as if "set arm fallback-mode arm".
3054 set disable-randomization
3055 show disable-randomization
3056 Standalone programs run with the virtual address space randomization enabled
3057 by default on some platforms. This option keeps the addresses stable across
3058 multiple debugging sessions.
3062 Control whether other threads are stopped or not when some thread hits
3067 Requests that asynchronous execution is enabled in the target, if available.
3068 In this case, it's possible to resume target in the background, and interact
3069 with GDB while the target is running. "show target-async" displays the
3070 current state of asynchronous execution of the target.
3072 set target-wide-charset
3073 show target-wide-charset
3074 The target-wide-charset is the name of the character set that GDB
3075 uses when printing characters whose type is wchar_t.
3077 set tcp auto-retry (on|off)
3079 set tcp connect-timeout
3080 show tcp connect-timeout
3081 These commands allow GDB to retry failed TCP connections to a remote stub
3082 with a specified timeout period; this is useful if the stub is launched
3083 in parallel with GDB but may not be ready to accept connections immediately.
3085 set libthread-db-search-path
3086 show libthread-db-search-path
3087 Control list of directories which GDB will search for appropriate
3090 set schedule-multiple (on|off)
3091 show schedule-multiple
3092 Allow GDB to resume all threads of all processes or only threads of
3093 the current process.
3097 Use more aggressive caching for accesses to the stack. This improves
3098 performance of remote debugging (particularly backtraces) without
3099 affecting correctness.
3101 set interactive-mode (on|off|auto)
3102 show interactive-mode
3103 Control whether GDB runs in interactive mode (on) or not (off).
3104 When in interactive mode, GDB waits for the user to answer all
3105 queries. Otherwise, GDB does not wait and assumes the default
3106 answer. When set to auto (the default), GDB determines which
3107 mode to use based on the stdin settings.
3112 For program forks, this is replaced by the new more generic `info
3113 inferiors' command. To list checkpoints, you can still use the
3114 `info checkpoints' command, which was an alias for the `info forks'
3118 Replaced by the new `inferior' command. To switch between
3119 checkpoints, you can still use the `restart' command, which was an
3120 alias for the `fork' command.
3123 This is removed, since some targets don't have a notion of
3124 processes. To switch between processes, you can still use the
3125 `inferior' command using GDB's own inferior number.
3128 For program forks, this is replaced by the new more generic `kill
3129 inferior' command. To delete a checkpoint, you can still use the
3130 `delete checkpoint' command, which was an alias for the `delete
3134 For program forks, this is replaced by the new more generic `detach
3135 inferior' command. To detach a checkpoint, you can still use the
3136 `detach checkpoint' command, which was an alias for the `detach
3139 * New native configurations
3141 x86/x86_64 Darwin i[34567]86-*-darwin*
3143 x86_64 MinGW x86_64-*-mingw*
3147 Lattice Mico32 lm32-*
3148 x86 DICOS i[34567]86-*-dicos*
3149 x86_64 DICOS x86_64-*-dicos*
3152 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3153 (mingw32ce) debugging.
3159 These commands were actually not implemented on any target.
3161 *** Changes in GDB 6.8
3163 * New native configurations
3165 NetBSD/hppa hppa*-*netbsd*
3166 Xtensa GNU/Linux xtensa*-*-linux*
3170 NetBSD/hppa hppa*-*-netbsd*
3171 Xtensa GNU/Lunux xtensa*-*-linux*
3173 * Change in command line behavior -- corefiles vs. process ids.
3175 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3176 attaching to process NUMBER fails, GDB no longer attempts to open a
3177 core file named NUMBER. Attaching to a program using the -c option
3178 is no longer supported. Instead, use the '-p' or '--pid' options.
3180 * GDB can now be built as a native debugger for debugging Windows x86
3181 (mingw32) Portable Executable (PE) programs.
3183 * Pending breakpoints no longer change their number when their address
3186 * GDB now supports breakpoints with multiple locations,
3187 including breakpoints on C++ constructors, inside C++ templates,
3188 and in inlined functions.
3190 * GDB's ability to debug optimized code has been improved. GDB more
3191 accurately identifies function bodies and lexical blocks that occupy
3192 more than one contiguous range of addresses.
3194 * Target descriptions can now describe registers for PowerPC.
3196 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3197 registers on PowerPC targets.
3199 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3200 targets even when the libthread_db library is not available.
3202 * The GDB remote stub, gdbserver, now supports the new file transfer
3203 commands (remote put, remote get, and remote delete).
3205 * The GDB remote stub, gdbserver, now supports run and attach in
3206 extended-remote mode.
3208 * hppa*64*-*-hpux11* target broken
3209 The debugger is unable to start a program and fails with the following
3210 error: "Error trying to get information about dynamic linker".
3211 The gdb-6.7 release is also affected.
3213 * GDB now supports the --enable-targets= configure option to allow
3214 building a single GDB executable that supports multiple remote
3215 target architectures.
3217 * GDB now supports debugging C and C++ programs which use the
3218 Decimal Floating Point extension. In addition, the PowerPC target
3219 now has a set of pseudo-registers to inspect decimal float values
3220 stored in two consecutive float registers.
3222 * The -break-insert MI command can optionally create pending
3225 * Improved support for debugging Ada
3226 Many improvements to the Ada language support have been made. These
3228 - Better support for Ada2005 interface types
3229 - Improved handling of arrays and slices in general
3230 - Better support for Taft-amendment types
3231 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3233 - Improved command completion in Ada
3236 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3241 set print frame-arguments (all|scalars|none)
3242 show print frame-arguments
3243 The value of this variable can be changed to control which argument
3244 values should be printed by the debugger when displaying a frame.
3249 Transfer files to and from a remote target, and delete remote files.
3256 Transfer files to and from a remote target, and delete remote files.
3258 * New remote packets
3265 Open, close, read, write, and delete files on the remote system.
3268 Attach to an existing process on the remote system, in extended-remote
3272 Run a new process on the remote system, in extended-remote mode.
3274 *** Changes in GDB 6.7
3276 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3277 bfd, libiberty and opcodes, as revealed by static analysis donated by
3278 Coverity, Inc. (http://scan.coverity.com).
3280 * When looking up multiply-defined global symbols, GDB will now prefer the
3281 symbol definition in the current shared library if it was built using the
3282 -Bsymbolic linker option.
3284 * When the Text User Interface (TUI) is not configured, GDB will now
3285 recognize the -tui command-line option and print a message that the TUI
3288 * The GDB remote stub, gdbserver, now has lower overhead for high
3289 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3291 * GDB for MIPS targets now autodetects whether a remote target provides
3292 32-bit or 64-bit register values.
3294 * Support for C++ member pointers has been improved.
3296 * GDB now understands XML target descriptions, which specify the
3297 target's overall architecture. GDB can read a description from
3298 a local file or over the remote serial protocol.
3300 * Vectors of single-byte data use a new integer type which is not
3301 automatically displayed as character or string data.
3303 * The /s format now works with the print command. It displays
3304 arrays of single-byte integers and pointers to single-byte integers
3307 * Target descriptions can now describe target-specific registers,
3308 for architectures which have implemented the support (currently
3309 only ARM, M68K, and MIPS).
3311 * GDB and the GDB remote stub, gdbserver, now support the XScale
3314 * The GDB remote stub, gdbserver, has been updated to support
3315 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3316 has been rewritten to use the standard GDB remote protocol.
3318 * GDB can now step into C++ functions which are called through thunks.
3320 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3322 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3323 layout. It also supports a TextSeg= and DataSeg= response when only
3324 segment base addresses (rather than offsets) are available.
3326 * The /i format now outputs any trailing branch delay slot instructions
3327 immediately following the last instruction within the count specified.
3329 * The GDB remote protocol "T" stop reply packet now supports a
3330 "library" response. Combined with the new "qXfer:libraries:read"
3331 packet, this response allows GDB to debug shared libraries on targets
3332 where the operating system manages the list of loaded libraries (e.g.
3333 Windows and SymbianOS).
3335 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3336 (DLLs) on Windows and Windows CE targets.
3338 * GDB now supports a faster verification that a .debug file matches its binary
3339 according to its build-id signature, if the signature is present.
3345 Enable or disable hardware flow control (RTS/CTS) on the serial port
3346 when debugging using remote targets.
3348 set mem inaccessible-by-default
3349 show mem inaccessible-by-default
3350 If the target supplies a memory map, for instance via the remote
3351 protocol's "qXfer:memory-map:read" packet, setting this variable
3352 prevents GDB from accessing memory outside the memory map. This
3353 is useful for targets with memory mapped registers or which react
3354 badly to accesses of unmapped address space.
3356 set breakpoint auto-hw
3357 show breakpoint auto-hw
3358 If the target supplies a memory map, for instance via the remote
3359 protocol's "qXfer:memory-map:read" packet, setting this variable
3360 lets GDB use hardware breakpoints automatically for memory regions
3361 where it can not use software breakpoints. This covers both the
3362 "break" command and internal breakpoints used for other commands
3363 including "next" and "finish".
3366 catch exception unhandled
3367 Stop the program execution when Ada exceptions are raised.
3370 Stop the program execution when an Ada assertion failed.
3374 Set an alternate system root for target files. This is a more
3375 general version of "set solib-absolute-prefix", which is now
3376 an alias to "set sysroot".
3379 Provide extended SPU facility status information. This set of
3380 commands is available only when debugging the Cell/B.E. SPU
3383 * New native configurations
3385 OpenBSD/sh sh*-*openbsd*
3388 unset tdesc filename
3390 Use the specified local file as an XML target description, and do
3391 not query the target for its built-in description.
3395 OpenBSD/sh sh*-*-openbsd*
3396 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3397 Toshiba Media Processor mep-elf
3399 * New remote packets
3402 Ignore the specified signals; pass them directly to the debugged program
3403 without stopping other threads or reporting them to GDB.
3405 qXfer:features:read:
3406 Read an XML target description from the target, which describes its
3411 Read or write contents of an spufs file on the target system. These
3412 packets are available only on the Cell/B.E. SPU architecture.
3414 qXfer:libraries:read:
3415 Report the loaded shared libraries. Combined with new "T" packet
3416 response, this packet allows GDB to debug shared libraries on
3417 targets where the operating system manages the list of loaded
3418 libraries (e.g. Windows and SymbianOS).
3422 Support for these obsolete configurations has been removed.
3430 i[34567]86-*-lynxos*
3431 i[34567]86-*-netware*
3432 i[34567]86-*-sco3.2v5*
3433 i[34567]86-*-sco3.2v4*
3435 i[34567]86-*-sysv4.2*
3438 i[34567]86-*-unixware2*
3439 i[34567]86-*-unixware*
3448 * Other removed features
3455 Various m68k-only ROM monitors.
3462 Various Renesas ROM monitors and debugging interfaces for SH and
3467 Support for a Macraigor serial interface to on-chip debugging.
3468 GDB does not directly support the newer parallel or USB
3473 A debug information format. The predecessor to DWARF 2 and
3474 DWARF 3, which are still supported.
3476 Support for the HP aCC compiler on HP-UX/PA-RISC
3478 SOM-encapsulated symbolic debugging information, automatic
3479 invocation of pxdb, and the aCC custom C++ ABI. This does not
3480 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3481 with aCC can still be debugged on an assembly level.
3483 MIPS ".pdr" sections
3485 A MIPS-specific format used to describe stack frame layout
3486 in debugging information.
3490 GDB could work with an older version of Guile to debug
3491 the interpreter and Scheme programs running in it.
3493 set mips stack-arg-size
3494 set mips saved-gpreg-size
3496 Use "set mips abi" to control parameter passing for MIPS.
3498 *** Changes in GDB 6.6
3503 Cell Broadband Engine SPU spu-elf
3505 * GDB can now be configured as a cross-debugger targeting native Windows
3506 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3507 running on a Windows system over TCP/IP to debug Windows programs.
3509 * The GDB remote stub, gdbserver, has been updated to support Windows and
3510 Cygwin debugging. Both single-threaded and multi-threaded programs are
3513 * The "set trust-readonly-sections" command works again. This command was
3514 broken in GDB 6.3, 6.4, and 6.5.
3516 * The "load" command now supports writing to flash memory, if the remote
3517 stub provides the required support.
3519 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3520 longer requires symbolic debug information (e.g. DWARF-2).
3525 unset substitute-path
3526 show substitute-path
3527 Manage a list of substitution rules that GDB uses to rewrite the name
3528 of the directories where the sources are located. This can be useful
3529 for instance when the sources were moved to a different location
3530 between compilation and debugging.
3534 Print each CLI command as it is executed. Each command is prefixed with
3535 a number of `+' symbols representing the nesting depth.
3536 The source command now has a `-v' option to enable the same feature.
3540 The ARM Demon monitor support (RDP protocol, "target rdp").
3542 Kernel Object Display, an embedded debugging feature which only worked with
3543 an obsolete version of Cisco IOS.
3545 The 'set download-write-size' and 'show download-write-size' commands.
3547 * New remote packets
3550 Tell a stub about GDB client features, and request remote target features.
3551 The first feature implemented is PacketSize, which allows the target to
3552 specify the size of packets it can handle - to minimize the number of
3553 packets required and improve performance when connected to a remote
3557 Fetch an OS auxilliary vector from the remote stub. This packet is a
3558 more efficient replacement for qPart:auxv:read.
3560 qXfer:memory-map:read:
3561 Fetch a memory map from the remote stub, including information about
3562 RAM, ROM, and flash memory devices.
3567 Erase and program a flash memory device.
3569 * Removed remote packets
3572 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3573 used it, and only gdbserver implemented it.
3575 *** Changes in GDB 6.5
3579 Renesas M32C/M16C m32c-elf
3581 Morpho Technologies ms1 ms1-elf
3585 init-if-undefined Initialize a convenience variable, but
3586 only if it doesn't already have a value.
3588 The following commands are presently only implemented for native GNU/Linux:
3590 checkpoint Save a snapshot of the program state.
3592 restart <n> Return the program state to a
3593 previously saved state.
3595 info checkpoints List currently saved checkpoints.
3597 delete-checkpoint <n> Delete a previously saved checkpoint.
3599 set|show detach-on-fork Tell gdb whether to detach from a newly
3600 forked process, or to keep debugging it.
3602 info forks List forks of the user program that
3603 are available to be debugged.
3605 fork <n> Switch to debugging one of several
3606 forks of the user program that are
3607 available to be debugged.
3609 delete-fork <n> Delete a fork from the list of forks
3610 that are available to be debugged (and
3611 kill the forked process).
3613 detach-fork <n> Delete a fork from the list of forks
3614 that are available to be debugged (and
3615 allow the process to continue).
3619 Morpho Technologies ms2 ms1-elf
3621 * Improved Windows host support
3623 GDB now builds as a cross debugger hosted on i686-mingw32, including
3624 native console support, and remote communications using either
3625 network sockets or serial ports.
3627 * Improved Modula-2 language support
3629 GDB can now print most types in the Modula-2 syntax. This includes:
3630 basic types, set types, record types, enumerated types, range types,
3631 pointer types and ARRAY types. Procedure var parameters are correctly
3632 printed and hexadecimal addresses and character constants are also
3633 written in the Modula-2 syntax. Best results can be obtained by using
3634 GNU Modula-2 together with the -gdwarf-2 command line option.
3638 The ARM rdi-share module.
3640 The Netware NLM debug server.
3642 *** Changes in GDB 6.4
3644 * New native configurations
3646 OpenBSD/arm arm*-*-openbsd*
3647 OpenBSD/mips64 mips64-*-openbsd*
3651 Morpho Technologies ms1 ms1-elf
3653 * New command line options
3655 --batch-silent As for --batch, but totally silent.
3656 --return-child-result The debugger will exist with the same value
3657 the child (debugged) program exited with.
3658 --eval-command COMMAND, -ex COMMAND
3659 Execute a single GDB CLI command. This may be
3660 specified multiple times and in conjunction
3661 with the --command (-x) option.
3663 * Deprecated commands removed
3665 The following commands, that were deprecated in 2000, have been
3669 set|show arm disassembly-flavor set|show arm disassembler
3670 othernames set arm disassembler
3671 set|show remotedebug set|show debug remote
3672 set|show archdebug set|show debug arch
3673 set|show eventdebug set|show debug event
3676 * New BSD user-level threads support
3678 It is now possible to debug programs using the user-level threads
3679 library on OpenBSD and FreeBSD. Currently supported (target)
3682 FreeBSD/amd64 x86_64-*-freebsd*
3683 FreeBSD/i386 i386-*-freebsd*
3684 OpenBSD/i386 i386-*-openbsd*
3686 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3687 are not yet supported.
3689 * New support for Matsushita MN10300 w/sim added
3690 (Work in progress). mn10300-elf.
3692 * REMOVED configurations and files
3694 VxWorks and the XDR protocol *-*-vxworks
3695 Motorola MCORE mcore-*-*
3696 National Semiconductor NS32000 ns32k-*-*
3698 * New "set print array-indexes" command
3700 After turning this setting "on", GDB prints the index of each element
3701 when displaying arrays. The default is "off" to preserve the previous
3704 * VAX floating point support
3706 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3708 * User-defined command support
3710 In addition to using $arg0..$arg9 for argument passing, it is now possible
3711 to use $argc to determine now many arguments have been passed. See the
3712 section on user-defined commands in the user manual for more information.
3714 *** Changes in GDB 6.3:
3716 * New command line option
3718 GDB now accepts -l followed by a number to set the timeout for remote
3721 * GDB works with GCC -feliminate-dwarf2-dups
3723 GDB now supports a more compact representation of DWARF-2 debug
3724 information using DW_FORM_ref_addr references. These are produced
3725 by GCC with the option -feliminate-dwarf2-dups and also by some
3726 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3727 to use -feliminate-dwarf2-dups.
3729 * Internationalization
3731 When supported by the host system, GDB will be built with
3732 internationalization (libintl). The task of marking up the sources is
3733 continued, we're looking forward to our first translation.
3737 Initial support for debugging programs compiled with the GNAT
3738 implementation of the Ada programming language has been integrated
3739 into GDB. In this release, support is limited to expression evaluation.
3741 * New native configurations
3743 GNU/Linux/m32r m32r-*-linux-gnu
3747 GDB's remote protocol now includes support for the 'p' packet. This
3748 packet is used to fetch individual registers from a remote inferior.
3750 * END-OF-LIFE registers[] compatibility module
3752 GDB's internal register infrastructure has been completely rewritten.
3753 The new infrastructure making possible the implementation of key new
3754 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3757 GDB 6.3 will be the last release to include the the registers[]
3758 compatibility module that allowed out-of-date configurations to
3759 continue to work. This change directly impacts the following
3769 powerpc bdm protocol
3771 Unless there is activity to revive these configurations, they will be
3772 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3774 * OBSOLETE configurations and files
3776 Configurations that have been declared obsolete in this release have
3777 been commented out. Unless there is activity to revive these
3778 configurations, the next release of GDB will have their sources
3779 permanently REMOVED.
3788 *** Changes in GDB 6.2.1:
3790 * MIPS `break main; run' gave an heuristic-fence-post warning
3792 When attempting to run even a simple program, a warning about
3793 heuristic-fence-post being hit would be reported. This problem has
3796 * MIPS IRIX 'long double' crashed GDB
3798 When examining a long double variable, GDB would get a segmentation
3799 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3800 IRIX long double values).
3804 A bug in the VAX stack code was causing problems with the "next"
3805 command. This problem has been fixed.
3807 *** Changes in GDB 6.2:
3809 * Fix for ``many threads''
3811 On GNU/Linux systems that use the NPTL threads library, a program
3812 rapidly creating and deleting threads would confuse GDB leading to the
3815 ptrace: No such process.
3816 thread_db_get_info: cannot get thread info: generic error
3818 This problem has been fixed.
3820 * "-async" and "-noasync" options removed.
3822 Support for the broken "-noasync" option has been removed (it caused
3825 * New ``start'' command.
3827 This command runs the program until the begining of the main procedure.
3829 * New BSD Kernel Data Access Library (libkvm) interface
3831 Using ``target kvm'' it is now possible to debug kernel core dumps and
3832 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3833 platforms. Currently supported (native-only) configurations are:
3835 FreeBSD/amd64 x86_64-*-freebsd*
3836 FreeBSD/i386 i?86-*-freebsd*
3837 NetBSD/i386 i?86-*-netbsd*
3838 NetBSD/m68k m68*-*-netbsd*
3839 NetBSD/sparc sparc-*-netbsd*
3840 OpenBSD/amd64 x86_64-*-openbsd*
3841 OpenBSD/i386 i?86-*-openbsd*
3842 OpenBSD/m68k m68*-openbsd*
3843 OpenBSD/sparc sparc-*-openbsd*
3845 * Signal trampoline code overhauled
3847 Many generic problems with GDB's signal handling code have been fixed.
3848 These include: backtraces through non-contiguous stacks; recognition
3849 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3850 call; backtrace through a signal trampoline; step into and out of
3851 signal handlers; and single-stepping in the signal trampoline.
3853 Please note that kernel bugs are a limiting factor here. These
3854 features have been shown to work on an s390 GNU/Linux system that
3855 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3857 * Cygwin support for DWARF 2 added.
3859 * New native configurations
3861 GNU/Linux/hppa hppa*-*-linux*
3862 OpenBSD/hppa hppa*-*-openbsd*
3863 OpenBSD/m68k m68*-*-openbsd*
3864 OpenBSD/m88k m88*-*-openbsd*
3865 OpenBSD/powerpc powerpc-*-openbsd*
3866 NetBSD/vax vax-*-netbsd*
3867 OpenBSD/vax vax-*-openbsd*
3869 * END-OF-LIFE frame compatibility module
3871 GDB's internal frame infrastructure has been completely rewritten.
3872 The new infrastructure making it possible to support key new features
3873 including DWARF 2 Call Frame Information. To aid in the task of
3874 migrating old configurations to this new infrastructure, a
3875 compatibility module, that allowed old configurations to continue to
3876 work, was also included.
3878 GDB 6.2 will be the last release to include this frame compatibility
3879 module. This change directly impacts the following configurations:
3889 Unless there is activity to revive these configurations, they will be
3890 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3892 * REMOVED configurations and files
3894 Sun 3, running SunOS 3 m68*-*-sunos3*
3895 Sun 3, running SunOS 4 m68*-*-sunos4*
3896 Sun 2, running SunOS 3 m68000-*-sunos3*
3897 Sun 2, running SunOS 4 m68000-*-sunos4*
3898 Motorola 680x0 running LynxOS m68*-*-lynxos*
3899 AT&T 3b1/Unix pc m68*-att-*
3900 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3901 decstation mips-dec-* mips-little-*
3902 riscos mips-*-riscos* mips-*-sysv*
3903 sonymips mips-sony-*
3904 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3906 *** Changes in GDB 6.1.1:
3908 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3910 The TUI (Text-mode User Interface) is now built as part of a default
3911 GDB configuration. It is enabled by either selecting the TUI with the
3912 command line option "-i=tui" or by running the separate "gdbtui"
3913 program. For more information on the TUI, see the manual "Debugging
3916 * Pending breakpoint support (also included in GDB 6.1)
3918 Support has been added to allow you to specify breakpoints in shared
3919 libraries that have not yet been loaded. If a breakpoint location
3920 cannot be found, and the "breakpoint pending" option is set to auto,
3921 GDB queries you if you wish to make the breakpoint pending on a future
3922 shared-library load. If and when GDB resolves the breakpoint symbol,
3923 the pending breakpoint is removed as one or more regular breakpoints
3926 Pending breakpoints are very useful for GCJ Java debugging.
3928 * Fixed ISO-C build problems
3930 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3931 non ISO-C code that stopped them being built using a more strict ISO-C
3932 compiler (e.g., IBM's C compiler).
3934 * Fixed build problem on IRIX 5
3936 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3937 wasn't able to compile compile on an IRIX 5 system.
3939 * Added execute permission to gdb/gdbserver/configure
3941 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3942 permission. This bug would cause configure to fail on a number of
3943 systems (Solaris, IRIX). Ref: server/519.
3945 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3947 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3948 has been updated to use constant array sizes.
3950 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3952 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3953 its generated DWARF Call Frame Info. This encoding was causing GDB to
3954 panic, that panic has been fixed. Ref: gdb/1628.
3956 * Fixed a problem when examining parameters in shared library code.
3958 When examining parameters in optimized shared library code generated
3959 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3960 not available''. GDB now correctly displays the variable's value.
3962 *** Changes in GDB 6.1:
3964 * Removed --with-mmalloc
3966 Support for the mmalloc memory manager has been removed, as it
3967 conflicted with the internal gdb byte cache.
3969 * Changes in AMD64 configurations
3971 The AMD64 target now includes the %cs and %ss registers. As a result
3972 the AMD64 remote protocol has changed; this affects the floating-point
3973 and SSE registers. If you rely on those registers for your debugging,
3974 you should upgrade gdbserver on the remote side.
3976 * Revised SPARC target
3978 The SPARC target has been completely revised, incorporating the
3979 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3980 support for LynxOS and SunOS 4 has been dropped. Calling functions
3981 from within GDB on operating systems with a non-executable stack
3982 (Solaris, OpenBSD) now works.
3986 GDB has a new C++ demangler which does a better job on the mangled
3987 names generated by current versions of g++. It also runs faster, so
3988 with this and other changes gdb should now start faster on large C++
3991 * DWARF 2 Location Expressions
3993 GDB support for location expressions has been extended to support function
3994 arguments and frame bases. Older versions of GDB could crash when they
3997 * C++ nested types and namespaces
3999 GDB's support for nested types and namespaces in C++ has been
4000 improved, especially if you use the DWARF 2 debugging format. (This
4001 is the default for recent versions of GCC on most platforms.)
4002 Specifically, if you have a class "Inner" defined within a class or
4003 namespace "Outer", then GDB realizes that the class's name is
4004 "Outer::Inner", not simply "Inner". This should greatly reduce the
4005 frequency of complaints about not finding RTTI symbols. In addition,
4006 if you are stopped at inside of a function defined within a namespace,
4007 GDB modifies its name lookup accordingly.
4009 * New native configurations
4011 NetBSD/amd64 x86_64-*-netbsd*
4012 OpenBSD/amd64 x86_64-*-openbsd*
4013 OpenBSD/alpha alpha*-*-openbsd*
4014 OpenBSD/sparc sparc-*-openbsd*
4015 OpenBSD/sparc64 sparc64-*-openbsd*
4017 * New debugging protocols
4019 M32R with SDI protocol m32r-*-elf*
4021 * "set prompt-escape-char" command deleted.
4023 The command "set prompt-escape-char" has been deleted. This command,
4024 and its very obscure effet on GDB's prompt, was never documented,
4025 tested, nor mentioned in the NEWS file.
4027 * OBSOLETE configurations and files
4029 Configurations that have been declared obsolete in this release have
4030 been commented out. Unless there is activity to revive these
4031 configurations, the next release of GDB will have their sources
4032 permanently REMOVED.
4034 Sun 3, running SunOS 3 m68*-*-sunos3*
4035 Sun 3, running SunOS 4 m68*-*-sunos4*
4036 Sun 2, running SunOS 3 m68000-*-sunos3*
4037 Sun 2, running SunOS 4 m68000-*-sunos4*
4038 Motorola 680x0 running LynxOS m68*-*-lynxos*
4039 AT&T 3b1/Unix pc m68*-att-*
4040 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4041 decstation mips-dec-* mips-little-*
4042 riscos mips-*-riscos* mips-*-sysv*
4043 sonymips mips-sony-*
4044 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4046 * REMOVED configurations and files
4048 SGI Irix-4.x mips-sgi-irix4 or iris4
4049 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4050 Z8000 simulator z8k-zilog-none or z8ksim
4051 Matsushita MN10200 w/simulator mn10200-*-*
4052 H8/500 simulator h8500-hitachi-hms or h8500hms
4053 HP/PA running BSD hppa*-*-bsd*
4054 HP/PA running OSF/1 hppa*-*-osf*
4055 HP/PA Pro target hppa*-*-pro*
4056 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4057 386BSD i[3456]86-*-bsd*
4058 Sequent family i[3456]86-sequent-sysv4*
4059 i[3456]86-sequent-sysv*
4060 i[3456]86-sequent-bsd*
4061 SPARC running LynxOS sparc-*-lynxos*
4062 SPARC running SunOS 4 sparc-*-sunos4*
4063 Tsqware Sparclet sparclet-*-*
4064 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4066 *** Changes in GDB 6.0:
4070 Support for debugging the Objective-C programming language has been
4071 integrated into GDB.
4073 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4075 DWARF 2's Call Frame Information makes available compiler generated
4076 information that more exactly describes the program's run-time stack.
4077 By using this information, GDB is able to provide more robust stack
4080 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4081 have been updated to use a new backtrace mechanism which includes
4082 DWARF 2 CFI support.
4086 GDB's remote protocol has been extended to include support for hosted
4087 file I/O (where the remote target uses GDB's file system). See GDB's
4088 remote protocol documentation for details.
4090 * All targets using the new architecture framework.
4092 All of GDB's targets have been updated to use the new internal
4093 architecture framework. The way is now open for future GDB releases
4094 to include cross-architecture native debugging support (i386 on amd64,
4097 * GNU/Linux's Thread Local Storage (TLS)
4099 GDB now includes support for for the GNU/Linux implementation of
4100 per-thread variables.
4102 * GNU/Linux's Native POSIX Thread Library (NPTL)
4104 GDB's thread code has been updated to work with either the new
4105 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4107 * Separate debug info.
4109 GDB, in conjunction with BINUTILS, now supports a mechanism for
4110 automatically loading debug information from a separate file. Instead
4111 of shipping full debug and non-debug versions of system libraries,
4112 system integrators can now instead ship just the stripped libraries
4113 and optional debug files.
4115 * DWARF 2 Location Expressions
4117 DWARF 2 Location Expressions allow the compiler to more completely
4118 describe the location of variables (even in optimized code) to the
4121 GDB now includes preliminary support for location expressions (support
4122 for DW_OP_piece is still missing).
4126 A number of long standing bugs that caused GDB to die while starting a
4127 Java application have been fixed. GDB's Java support is now
4128 considered "useable".
4130 * GNU/Linux support for fork, vfork, and exec.
4132 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4133 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4136 * GDB supports logging output to a file
4138 There are two new commands, "set logging" and "show logging", which can be
4139 used to capture GDB's output to a file.
4141 * The meaning of "detach" has changed for gdbserver
4143 The "detach" command will now resume the application, as documented. To
4144 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4147 * d10v, m68hc11 `regs' command deprecated
4149 The `info registers' command has been updated so that it displays the
4150 registers using a format identical to the old `regs' command.
4154 A new command, "maint set profile on/off", has been added. This command can
4155 be used to enable or disable profiling while running GDB, to profile a
4156 session or a set of commands. In addition there is a new configure switch,
4157 "--enable-profiling", which will cause GDB to be compiled with profiling
4158 data, for more informative profiling results.
4160 * Default MI syntax changed to "mi2".
4162 The default MI (machine interface) syntax, enabled by the command line
4163 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4164 "mi1", can be enabled by specifying the option "-i=mi1".
4166 Support for the original "mi0" syntax (included in GDB 5.0) has been
4169 Fix for gdb/192: removed extraneous space when displaying frame level.
4170 Fix for gdb/672: update changelist is now output in mi list format.
4171 Fix for gdb/702: a -var-assign that updates the value now shows up
4172 in a subsequent -var-update.
4174 * New native configurations.
4176 FreeBSD/amd64 x86_64-*-freebsd*
4178 * Multi-arched targets.
4180 HP/PA HPUX11 hppa*-*-hpux*
4181 Renesas M32R/D w/simulator m32r-*-elf*
4183 * OBSOLETE configurations and files
4185 Configurations that have been declared obsolete in this release have
4186 been commented out. Unless there is activity to revive these
4187 configurations, the next release of GDB will have their sources
4188 permanently REMOVED.
4190 Z8000 simulator z8k-zilog-none or z8ksim
4191 Matsushita MN10200 w/simulator mn10200-*-*
4192 H8/500 simulator h8500-hitachi-hms or h8500hms
4193 HP/PA running BSD hppa*-*-bsd*
4194 HP/PA running OSF/1 hppa*-*-osf*
4195 HP/PA Pro target hppa*-*-pro*
4196 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4197 Sequent family i[3456]86-sequent-sysv4*
4198 i[3456]86-sequent-sysv*
4199 i[3456]86-sequent-bsd*
4200 Tsqware Sparclet sparclet-*-*
4201 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4203 * REMOVED configurations and files
4206 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4207 IBM AIX PS/2 i[3456]86-*-aix
4208 i386 running Mach 3.0 i[3456]86-*-mach3*
4209 i386 running Mach i[3456]86-*-mach*
4210 i386 running OSF/1 i[3456]86-*osf1mk*
4211 HP/Apollo 68k Family m68*-apollo*-sysv*,
4213 m68*-hp-bsd*, m68*-hp-hpux*
4214 Argonaut Risc Chip (ARC) arc-*-*
4215 Mitsubishi D30V d30v-*-*
4216 Fujitsu FR30 fr30-*-elf*
4217 OS/9000 i[34]86-*-os9k
4218 I960 with MON960 i960-*-coff
4220 * MIPS $fp behavior changed
4222 The convenience variable $fp, for the MIPS, now consistently returns
4223 the address of the current frame's base. Previously, depending on the
4224 context, $fp could refer to either $sp or the current frame's base
4225 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4226 The GNU Source-Level Debugger''.
4228 *** Changes in GDB 5.3:
4230 * GNU/Linux shared library multi-threaded performance improved.
4232 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4233 `/proc', in preference to `ptrace' for memory reads. This may result
4234 in an improvement in the start-up time of multi-threaded, shared
4235 library applications when run under GDB. One GDB user writes: ``loads
4236 shared libs like mad''.
4238 * ``gdbserver'' now supports multi-threaded applications on some targets
4240 Support for debugging multi-threaded applications which use
4241 the GNU/Linux LinuxThreads package has been added for
4242 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4243 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4245 * GDB now supports C/C++ preprocessor macros.
4247 GDB now expands preprocessor macro invocations in C/C++ expressions,
4248 and provides various commands for showing macro definitions and how
4251 The new command `macro expand EXPRESSION' expands any macro
4252 invocations in expression, and shows the result.
4254 The new command `show macro MACRO-NAME' shows the definition of the
4255 macro named MACRO-NAME, and where it was defined.
4257 Most compilers don't include information about macros in the debugging
4258 information by default. In GCC 3.1, for example, you need to compile
4259 your program with the options `-gdwarf-2 -g3'. If the macro
4260 information is present in the executable, GDB will read it.
4262 * Multi-arched targets.
4264 DEC Alpha (partial) alpha*-*-*
4265 DEC VAX (partial) vax-*-*
4267 National Semiconductor NS32000 (partial) ns32k-*-*
4268 Motorola 68000 (partial) m68k-*-*
4269 Motorola MCORE mcore-*-*
4273 Fujitsu FRV architecture added by Red Hat frv*-*-*
4276 * New native configurations
4278 Alpha NetBSD alpha*-*-netbsd*
4279 SH NetBSD sh*-*-netbsdelf*
4280 MIPS NetBSD mips*-*-netbsd*
4281 UltraSPARC NetBSD sparc64-*-netbsd*
4283 * OBSOLETE configurations and files
4285 Configurations that have been declared obsolete in this release have
4286 been commented out. Unless there is activity to revive these
4287 configurations, the next release of GDB will have their sources
4288 permanently REMOVED.
4290 Mitsubishi D30V d30v-*-*
4291 OS/9000 i[34]86-*-os9k
4292 IBM AIX PS/2 i[3456]86-*-aix
4293 Fujitsu FR30 fr30-*-elf*
4294 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4295 Argonaut Risc Chip (ARC) arc-*-*
4296 i386 running Mach 3.0 i[3456]86-*-mach3*
4297 i386 running Mach i[3456]86-*-mach*
4298 i386 running OSF/1 i[3456]86-*osf1mk*
4299 HP/Apollo 68k Family m68*-apollo*-sysv*,
4301 m68*-hp-bsd*, m68*-hp-hpux*
4302 I960 with MON960 i960-*-coff
4304 * OBSOLETE languages
4306 CHILL, a Pascal like language used by telecommunications companies.
4308 * REMOVED configurations and files
4310 AMD 29k family via UDI a29k-amd-udi, udi29k
4311 A29K VxWorks a29k-*-vxworks
4312 AMD 29000 embedded, using EBMON a29k-none-none
4313 AMD 29000 embedded with COFF a29k-none-coff
4314 AMD 29000 embedded with a.out a29k-none-aout
4316 testsuite/gdb.hp/gdb.threads-hp/ directory
4318 * New command "set max-user-call-depth <nnn>"
4320 This command allows the user to limit the call depth of user-defined
4321 commands. The default is 1024.
4323 * Changes in FreeBSD/i386 native debugging.
4325 Support for the "generate-core-file" has been added.
4327 * New commands "dump", "append", and "restore".
4329 These commands allow data to be copied from target memory
4330 to a bfd-format or binary file (dump and append), and back
4331 from a file into memory (restore).
4333 * Improved "next/step" support on multi-processor Alpha Tru64.
4335 The previous single-step mechanism could cause unpredictable problems,
4336 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4337 of a software single-step mechanism prevents this.
4339 *** Changes in GDB 5.2.1:
4347 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4348 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4349 Fix, by Joel Brobecker imported from mainline.
4351 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4352 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4353 Fix, by Fred Fish, imported from mainline.
4355 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4356 Surprisingly enough, it works now.
4357 By Michal Ludvig, imported from mainline.
4359 i386 hardware watchpoint support:
4360 avoid misses on second run for some targets.
4361 By Pierre Muller, imported from mainline.
4363 *** Changes in GDB 5.2:
4365 * New command "set trust-readonly-sections on[off]".
4367 This command is a hint that tells gdb that read-only sections
4368 really are read-only (ie. that their contents will not change).
4369 In this mode, gdb will go to the object file rather than the
4370 target to read memory from read-only sections (such as ".text").
4371 This can be a significant performance improvement on some
4372 (notably embedded) targets.
4374 * New command "generate-core-file" (or "gcore").
4376 This new gdb command allows the user to drop a core file of the child
4377 process state at any time. So far it's been implemented only for
4378 GNU/Linux and Solaris, but should be relatively easily ported to other
4379 hosts. Argument is core file name (defaults to core.<pid>).
4381 * New command line option
4383 GDB now accepts --pid or -p followed by a process id.
4385 * Change in command line behavior -- corefiles vs. process ids.
4387 There is a subtle behavior in the way in which GDB handles
4388 command line arguments. The first non-flag argument is always
4389 a program to debug, but the second non-flag argument may either
4390 be a corefile or a process id. Previously, GDB would attempt to
4391 open the second argument as a corefile, and if that failed, would
4392 issue a superfluous error message and then attempt to attach it as
4393 a process. Now, if the second argument begins with a non-digit,
4394 it will be treated as a corefile. If it begins with a digit,
4395 GDB will attempt to attach it as a process, and if no such process
4396 is found, will then attempt to open it as a corefile.
4398 * Changes in ARM configurations.
4400 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4401 configuration is fully multi-arch.
4403 * New native configurations
4405 ARM NetBSD arm*-*-netbsd*
4406 x86 OpenBSD i[3456]86-*-openbsd*
4407 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4408 Sparc64 running FreeBSD sparc64-*-freebsd*
4412 Sanyo XStormy16 xstormy16-elf
4414 * OBSOLETE configurations and files
4416 Configurations that have been declared obsolete in this release have
4417 been commented out. Unless there is activity to revive these
4418 configurations, the next release of GDB will have their sources
4419 permanently REMOVED.
4421 AMD 29k family via UDI a29k-amd-udi, udi29k
4422 A29K VxWorks a29k-*-vxworks
4423 AMD 29000 embedded, using EBMON a29k-none-none
4424 AMD 29000 embedded with COFF a29k-none-coff
4425 AMD 29000 embedded with a.out a29k-none-aout
4427 testsuite/gdb.hp/gdb.threads-hp/ directory
4429 * REMOVED configurations and files
4431 TI TMS320C80 tic80-*-*
4433 PowerPC Solaris powerpcle-*-solaris*
4434 PowerPC Windows NT powerpcle-*-cygwin32
4435 PowerPC Netware powerpc-*-netware*
4436 Harris/CXUX m88k m88*-harris-cxux*
4437 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4438 ns32k-utek-sysv* ns32k-utek-*
4439 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4440 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4441 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4442 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4443 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4445 * Changes to command line processing
4447 The new `--args' feature can be used to specify command-line arguments
4448 for the inferior from gdb's command line.
4450 * Changes to key bindings
4452 There is a new `operate-and-get-next' function bound to `C-o'.
4454 *** Changes in GDB 5.1.1
4456 Fix compile problem on DJGPP.
4458 Fix a problem with floating-point registers on the i386 being
4461 Fix to stop GDB crashing on .debug_str debug info.
4463 Numerous documentation fixes.
4465 Numerous testsuite fixes.
4467 *** Changes in GDB 5.1:
4469 * New native configurations
4471 Alpha FreeBSD alpha*-*-freebsd*
4472 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4473 MIPS GNU/Linux mips*-*-linux*
4474 MIPS SGI Irix 6.x mips*-sgi-irix6*
4475 ia64 AIX ia64-*-aix*
4476 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4480 Motorola 68HC11 and 68HC12 m68hc11-elf
4482 UltraSparc running GNU/Linux sparc64-*-linux*
4484 * OBSOLETE configurations and files
4486 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4487 Harris/CXUX m88k m88*-harris-cxux*
4488 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4489 ns32k-utek-sysv* ns32k-utek-*
4490 TI TMS320C80 tic80-*-*
4492 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4493 PowerPC Solaris powerpcle-*-solaris*
4494 PowerPC Windows NT powerpcle-*-cygwin32
4495 PowerPC Netware powerpc-*-netware*
4496 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4497 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4498 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4499 Apple Macintosh (MPW) host N/A
4501 stuff.c (Program to stuff files into a specially prepared space in kdb)
4502 kdb-start.c (Main loop for the standalone kernel debugger)
4504 Configurations that have been declared obsolete in this release have
4505 been commented out. Unless there is activity to revive these
4506 configurations, the next release of GDB will have their sources
4507 permanently REMOVED.
4509 * REMOVED configurations and files
4511 Altos 3068 m68*-altos-*
4512 Convex c1-*-*, c2-*-*
4514 ARM RISCix arm-*-* (as host)
4518 * GDB has been converted to ISO C.
4520 GDB's source code has been converted to ISO C. In particular, the
4521 sources are fully protoized, and rely on standard headers being
4526 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4528 * The MI enabled by default.
4530 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4531 revised and enabled by default. Packages which use GDB as a debugging
4532 engine behind a UI or another front end are encouraged to switch to
4533 using the GDB/MI interface, instead of the old annotations interface
4534 which is now deprecated.
4536 * Support for debugging Pascal programs.
4538 GDB now includes support for debugging Pascal programs. The following
4539 main features are supported:
4541 - Pascal-specific data types such as sets;
4543 - automatic recognition of Pascal sources based on file-name
4546 - Pascal-style display of data types, variables, and functions;
4548 - a Pascal expression parser.
4550 However, some important features are not yet supported.
4552 - Pascal string operations are not supported at all;
4554 - there are some problems with boolean types;
4556 - Pascal type hexadecimal constants are not supported
4557 because they conflict with the internal variables format;
4559 - support for Pascal objects and classes is not full yet;
4561 - unlike Pascal, GDB is case-sensitive for symbol names.
4563 * Changes in completion.
4565 Commands such as `shell', `run' and `set args', which pass arguments
4566 to inferior programs, now complete on file names, similar to what
4567 users expect at the shell prompt.
4569 Commands which accept locations, such as `disassemble', `print',
4570 `breakpoint', `until', etc. now complete on filenames as well as
4571 program symbols. Thus, if you type "break foob TAB", and the source
4572 files linked into the programs include `foobar.c', that file name will
4573 be one of the candidates for completion. However, file names are not
4574 considered for completion after you typed a colon that delimits a file
4575 name from a name of a function in that file, as in "break foo.c:bar".
4577 `set demangle-style' completes on available demangling styles.
4579 * New platform-independent commands:
4581 It is now possible to define a post-hook for a command as well as a
4582 hook that runs before the command. For more details, see the
4583 documentation of `hookpost' in the GDB manual.
4585 * Changes in GNU/Linux native debugging.
4587 Support for debugging multi-threaded programs has been completely
4588 revised for all platforms except m68k and sparc. You can now debug as
4589 many threads as your system allows you to have.
4591 Attach/detach is supported for multi-threaded programs.
4593 Support for SSE registers was added for x86. This doesn't work for
4594 multi-threaded programs though.
4596 * Changes in MIPS configurations.
4598 Multi-arch support is enabled for all MIPS configurations.
4600 GDB can now be built as native debugger on SGI Irix 6.x systems for
4601 debugging n32 executables. (Debugging 64-bit executables is not yet
4604 * Unified support for hardware watchpoints in all x86 configurations.
4606 Most (if not all) native x86 configurations support hardware-assisted
4607 breakpoints and watchpoints in a unified manner. This support
4608 implements debug register sharing between watchpoints, which allows to
4609 put a virtually infinite number of watchpoints on the same address,
4610 and also supports watching regions up to 16 bytes with several debug
4613 The new maintenance command `maintenance show-debug-regs' toggles
4614 debugging print-outs in functions that insert, remove, and test
4615 watchpoints and hardware breakpoints.
4617 * Changes in the DJGPP native configuration.
4619 New command ``info dos sysinfo'' displays assorted information about
4620 the CPU, OS, memory, and DPMI server.
4622 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4623 display information about segment descriptors stored in GDT, LDT, and
4626 New commands ``info dos pde'' and ``info dos pte'' display entries
4627 from Page Directory and Page Tables (for now works with CWSDPMI only).
4628 New command ``info dos address-pte'' displays the Page Table entry for
4629 a given linear address.
4631 GDB can now pass command lines longer than 126 characters to the
4632 program being debugged (requires an update to the libdbg.a library
4633 which is part of the DJGPP development kit).
4635 DWARF2 debug info is now supported.
4637 It is now possible to `step' and `next' through calls to `longjmp'.
4639 * Changes in documentation.
4641 All GDB documentation was converted to GFDL, the GNU Free
4642 Documentation License.
4644 Tracepoints-related commands are now fully documented in the GDB
4647 TUI, the Text-mode User Interface, is now documented in the manual.
4649 Tracepoints-related commands are now fully documented in the GDB
4652 The "GDB Internals" manual now has an index. It also includes
4653 documentation of `ui_out' functions, GDB coding standards, x86
4654 hardware watchpoints, and memory region attributes.
4656 * GDB's version number moved to ``version.in''
4658 The Makefile variable VERSION has been replaced by the file
4659 ``version.in''. People creating GDB distributions should update the
4660 contents of this file.
4664 GUD support is now a standard part of the EMACS distribution.
4666 *** Changes in GDB 5.0:
4668 * Improved support for debugging FP programs on x86 targets
4670 Unified and much-improved support for debugging floating-point
4671 programs on all x86 targets. In particular, ``info float'' now
4672 displays the FP registers in the same format on all x86 targets, with
4673 greater level of detail.
4675 * Improvements and bugfixes in hardware-assisted watchpoints
4677 It is now possible to watch array elements, struct members, and
4678 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4679 on x86 targets no longer erroneously trigger when the address is
4682 * Improvements in the native DJGPP version of GDB
4684 The distribution now includes all the scripts and auxiliary files
4685 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4686 machines ``out of the box''.
4688 The DJGPP version can now debug programs that use signals. It is
4689 possible to catch signals that happened in the debuggee, deliver
4690 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4691 would kill the program being debugged.) Programs that hook hardware
4692 interrupts (keyboard, timer, etc.) can also be debugged.
4694 It is now possible to debug DJGPP programs that redirect their
4695 standard handles or switch them to raw (as opposed to cooked) mode, or
4696 even close them. The command ``run < foo > bar'' works as expected,
4697 and ``info terminal'' reports useful information about the debuggee's
4698 terminal, including raw/cooked mode, redirection, etc.
4700 The DJGPP version now uses termios functions for console I/O, which
4701 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4704 DOS-style file names with drive letters are now fully supported by
4707 It is now possible to debug DJGPP programs that switch their working
4708 directory. It is also possible to rerun the debuggee any number of
4709 times without restarting GDB; thus, you can use the same setup,
4710 breakpoints, etc. for many debugging sessions.
4712 * New native configurations
4714 ARM GNU/Linux arm*-*-linux*
4715 PowerPC GNU/Linux powerpc-*-linux*
4719 Motorola MCore mcore-*-*
4720 x86 VxWorks i[3456]86-*-vxworks*
4721 PowerPC VxWorks powerpc-*-vxworks*
4722 TI TMS320C80 tic80-*-*
4724 * OBSOLETE configurations
4726 Altos 3068 m68*-altos-*
4727 Convex c1-*-*, c2-*-*
4729 ARM RISCix arm-*-* (as host)
4732 Configurations that have been declared obsolete will be commented out,
4733 but the code will be left in place. If there is no activity to revive
4734 these configurations before the next release of GDB, the sources will
4735 be permanently REMOVED.
4737 * Gould support removed
4739 Support for the Gould PowerNode and NP1 has been removed.
4741 * New features for SVR4
4743 On SVR4 native platforms (such as Solaris), if you attach to a process
4744 without first loading a symbol file, GDB will now attempt to locate and
4745 load symbols from the running process's executable file.
4747 * Many C++ enhancements
4749 C++ support has been greatly improved. Overload resolution now works properly
4750 in almost all cases. RTTI support is on the way.
4752 * Remote targets can connect to a sub-program
4754 A popen(3) style serial-device has been added. This device starts a
4755 sub-process (such as a stand-alone simulator) and then communicates
4756 with that. The sub-program to run is specified using the syntax
4757 ``|<program> <args>'' vis:
4759 (gdb) set remotedebug 1
4760 (gdb) target extended-remote |mn10300-elf-sim program-args
4762 * MIPS 64 remote protocol
4764 A long standing bug in the mips64 remote protocol where by GDB
4765 expected certain 32 bit registers (ex SR) to be transfered as 32
4766 instead of 64 bits has been fixed.
4768 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4769 added to provide backward compatibility with older versions of GDB.
4771 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4773 The command ``set remotebinarydownload'' command has been replaced by
4774 ``set remote X-packet''. Other commands in ``set remote'' family
4775 include ``set remote P-packet''.
4777 * Breakpoint commands accept ranges.
4779 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4780 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4781 ``tracepoint passcount'' also accepts a range of tracepoints.
4783 * ``apropos'' command added.
4785 The ``apropos'' command searches through command names and
4786 documentation strings, printing out matches, making it much easier to
4787 try to find a command that does what you are looking for.
4791 A new machine oriented interface (MI) has been added to GDB. This
4792 interface is designed for debug environments running GDB as a separate
4793 process. This is part of the long term libGDB project. See the
4794 "GDB/MI" chapter of the GDB manual for further information. It can be
4795 enabled by configuring with:
4797 .../configure --enable-gdbmi
4799 *** Changes in GDB-4.18:
4801 * New native configurations
4803 HP-UX 10.20 hppa*-*-hpux10.20
4804 HP-UX 11.x hppa*-*-hpux11.0*
4805 M68K GNU/Linux m68*-*-linux*
4809 Fujitsu FR30 fr30-*-elf*
4810 Intel StrongARM strongarm-*-*
4811 Mitsubishi D30V d30v-*-*
4813 * OBSOLETE configurations
4815 Gould PowerNode, NP1 np1-*-*, pn-*-*
4817 Configurations that have been declared obsolete will be commented out,
4818 but the code will be left in place. If there is no activity to revive
4819 these configurations before the next release of GDB, the sources will
4820 be permanently REMOVED.
4824 As a compatibility experiment, GDB's source files buildsym.h and
4825 buildsym.c have been converted to pure standard C, no longer
4826 containing any K&R compatibility code. We believe that all systems in
4827 use today either come with a standard C compiler, or have a GCC port
4828 available. If this is not true, please report the affected
4829 configuration to bug-gdb@gnu.org immediately. See the README file for
4830 information about getting a standard C compiler if you don't have one
4835 GDB now uses readline 2.2.
4837 * set extension-language
4839 You can now control the mapping between filename extensions and source
4840 languages by using the `set extension-language' command. For instance,
4841 you can ask GDB to treat .c files as C++ by saying
4842 set extension-language .c c++
4843 The command `info extensions' lists all of the recognized extensions
4844 and their associated languages.
4846 * Setting processor type for PowerPC and RS/6000
4848 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4849 you can use the `set processor' command to specify what variant of the
4850 PowerPC family you are debugging. The command
4854 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4855 following PowerPC and RS6000 variants:
4857 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4858 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4860 403GC IBM PowerPC 403GC
4861 505 Motorola PowerPC 505
4862 860 Motorola PowerPC 860 or 850
4863 601 Motorola PowerPC 601
4864 602 Motorola PowerPC 602
4865 603 Motorola/IBM PowerPC 603 or 603e
4866 604 Motorola PowerPC 604 or 604e
4867 750 Motorola/IBM PowerPC 750 or 750
4869 At the moment, this command just tells GDB what to name the
4870 special-purpose processor registers. Since almost all the affected
4871 registers are inaccessible to user-level programs, this command is
4872 only useful for remote debugging in its present form.
4876 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4877 more extensive support for HP-UX. Added features include shared
4878 library support, kernel threads and hardware watchpoints for 11.00,
4879 support for HP's ANSI C and C++ compilers, and a compatibility mode
4880 for xdb and dbx commands.
4884 HP's donation includes the new concept of catchpoints, which is a
4885 generalization of the old catch command. On HP-UX, it is now possible
4886 to catch exec, fork, and vfork, as well as library loading.
4888 This means that the existing catch command has changed; its first
4889 argument now specifies the type of catch to be set up. See the
4890 output of "help catch" for a list of catchpoint types.
4892 * Debugging across forks
4894 On HP-UX, you can choose which process to debug when a fork() happens
4899 HP has donated a curses-based terminal user interface (TUI). To get
4900 it, build with --enable-tui. Although this can be enabled for any
4901 configuration, at present it only works for native HP debugging.
4903 * GDB remote protocol additions
4905 A new protocol packet 'X' that writes binary data is now available.
4906 Default behavior is to try 'X', then drop back to 'M' if the stub
4907 fails to respond. The settable variable `remotebinarydownload'
4908 allows explicit control over the use of 'X'.
4910 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4911 full 64-bit address. The command
4913 set remoteaddresssize 32
4915 can be used to revert to the old behaviour. For existing remote stubs
4916 the change should not be noticed, as the additional address information
4919 In order to assist in debugging stubs, you may use the maintenance
4920 command `packet' to send any text string to the stub. For instance,
4922 maint packet heythere
4924 sends the packet "$heythere#<checksum>". Note that it is very easy to
4925 disrupt a debugging session by sending the wrong packet at the wrong
4928 The compare-sections command allows you to compare section data on the
4929 target to what is in the executable file without uploading or
4930 downloading, by comparing CRC checksums.
4932 * Tracing can collect general expressions
4934 You may now collect general expressions at tracepoints. This requires
4935 further additions to the target-side stub; see tracepoint.c and
4936 doc/agentexpr.texi for further details.
4938 * mask-address variable for Mips
4940 For Mips targets, you may control the zeroing of the upper 32 bits of
4941 a 64-bit address by entering `set mask-address on'. This is mainly
4942 of interest to users of embedded R4xxx and R5xxx processors.
4944 * Higher serial baud rates
4946 GDB's serial code now allows you to specify baud rates 57600, 115200,
4947 230400, and 460800 baud. (Note that your host system may not be able
4948 to achieve all of these rates.)
4952 The i960 configuration now includes an initial implementation of a
4953 builtin simulator, contributed by Jim Wilson.
4956 *** Changes in GDB-4.17:
4958 * New native configurations
4960 Alpha GNU/Linux alpha*-*-linux*
4961 Unixware 2.x i[3456]86-unixware2*
4962 Irix 6.x mips*-sgi-irix6*
4963 PowerPC GNU/Linux powerpc-*-linux*
4964 PowerPC Solaris powerpcle-*-solaris*
4965 Sparc GNU/Linux sparc-*-linux*
4966 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4970 Argonaut Risc Chip (ARC) arc-*-*
4971 Hitachi H8/300S h8300*-*-*
4972 Matsushita MN10200 w/simulator mn10200-*-*
4973 Matsushita MN10300 w/simulator mn10300-*-*
4974 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4975 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4976 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4977 Mitsubishi D10V w/simulator d10v-*-*
4978 Mitsubishi M32R/D w/simulator m32r-*-elf*
4979 Tsqware Sparclet sparclet-*-*
4980 NEC V850 w/simulator v850-*-*
4982 * New debugging protocols
4984 ARM with RDI protocol arm*-*-*
4985 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4986 DDB and LSI variants of PMON protocol mips*-*-*
4987 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4988 PowerPC with SDS protocol powerpc{,le}-*-eabi
4989 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4993 All configurations can now understand and use the DWARF 2 debugging
4994 format. The choice is automatic, if the symbol file contains DWARF 2
4999 GDB now includes basic Java language support. This support is
5000 only useful with Java compilers that produce native machine code.
5002 * solib-absolute-prefix and solib-search-path
5004 For SunOS and SVR4 shared libraries, you may now set the prefix for
5005 loading absolute shared library symbol files, and the search path for
5006 locating non-absolute shared library symbol files.
5008 * Live range splitting
5010 GDB can now effectively debug code for which GCC has performed live
5011 range splitting as part of its optimization. See gdb/doc/LRS for
5012 more details on the expected format of the stabs information.
5016 GDB's support for the GNU Hurd, including thread debugging, has been
5017 updated to work with current versions of the Hurd.
5021 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5022 instruction set. ARM GDB automatically detects when Thumb
5023 instructions are in use, and adjusts disassembly and backtracing
5028 GDB's MIPS target configurations now handle the MIP16 16-bit
5033 GDB now includes support for overlays; if an executable has been
5034 linked such that multiple sections are based at the same address, GDB
5035 will decide which section to use for symbolic info. You can choose to
5036 control the decision manually, using overlay commands, or implement
5037 additional target-side support and use "overlay load-target" to bring
5038 in the overlay mapping. Do "help overlay" for more detail.
5042 The command "info symbol <address>" displays information about
5043 the symbol at the specified address.
5047 The standard remote protocol now includes an extension that allows
5048 asynchronous collection and display of trace data. This requires
5049 extensive support in the target-side debugging stub. Tracing mode
5050 includes a new interaction mode in GDB and new commands: see the
5051 file tracepoint.c for more details.
5055 Configurations for embedded MIPS now include a simulator contributed
5056 by Cygnus Solutions. The simulator supports the instruction sets
5057 of most MIPS variants.
5061 Sparc configurations may now include the ERC32 simulator contributed
5062 by the European Space Agency. The simulator is not built into
5063 Sparc targets by default; configure with --enable-sim to include it.
5067 For target configurations that may include multiple variants of a
5068 basic architecture (such as MIPS and SH), you may now set the
5069 architecture explicitly. "set arch" sets, "info arch" lists
5070 the possible architectures.
5072 *** Changes in GDB-4.16:
5074 * New native configurations
5076 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5077 M68K NetBSD m68k-*-netbsd*
5078 PowerPC AIX 4.x powerpc-*-aix*
5079 PowerPC MacOS powerpc-*-macos*
5080 PowerPC Windows NT powerpcle-*-cygwin32
5081 RS/6000 AIX 4.x rs6000-*-aix4*
5085 ARM with RDP protocol arm-*-*
5086 I960 with MON960 i960-*-coff
5087 MIPS VxWorks mips*-*-vxworks*
5088 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5089 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5091 Matra Sparclet sparclet-*-*
5095 The powerpc-eabi configuration now includes the PSIM simulator,
5096 contributed by Andrew Cagney, with assistance from Mike Meissner.
5097 PSIM is a very elaborate model of the PowerPC, including not only
5098 basic instruction set execution, but also details of execution unit
5099 performance and I/O hardware. See sim/ppc/README for more details.
5103 GDB now works with Solaris 2.5.
5105 * Windows 95/NT native
5107 GDB will now work as a native debugger on Windows 95 and Windows NT.
5108 To build it from source, you must use the "gnu-win32" environment,
5109 which uses a DLL to emulate enough of Unix to run the GNU tools.
5110 Further information, binaries, and sources are available at
5111 ftp.cygnus.com, under pub/gnu-win32.
5113 * dont-repeat command
5115 If a user-defined command includes the command `dont-repeat', then the
5116 command will not be repeated if the user just types return. This is
5117 useful if the command is time-consuming to run, so that accidental
5118 extra keystrokes don't run the same command many times.
5120 * Send break instead of ^C
5122 The standard remote protocol now includes an option to send a break
5123 rather than a ^C to the target in order to interrupt it. By default,
5124 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5126 * Remote protocol timeout
5128 The standard remote protocol includes a new variable `remotetimeout'
5129 that allows you to set the number of seconds before GDB gives up trying
5130 to read from the target. The default value is 2.
5132 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5134 By default GDB will automatically keep track of objects as they are
5135 loaded and unloaded by the dynamic linker. By using the command `set
5136 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5137 when shared library events occur, thus allowing you to set breakpoints
5138 in shared libraries which are explicitly loaded by the inferior.
5140 Note this feature does not work on hpux8. On hpux9 you must link
5141 /usr/lib/end.o into your program. This feature should work
5142 automatically on hpux10.
5144 * Irix 5.x hardware watchpoint support
5146 Irix 5 configurations now support the use of hardware watchpoints.
5148 * Mips protocol "SYN garbage limit"
5150 When debugging a Mips target using the `target mips' protocol, you
5151 may set the number of characters that GDB will ignore by setting
5152 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5153 every character. The default value is 1050.
5155 * Recording and replaying remote debug sessions
5157 If you set `remotelogfile' to the name of a file, gdb will write to it
5158 a recording of a remote debug session. This recording may then be
5159 replayed back to gdb using "gdbreplay". See gdbserver/README for
5160 details. This is useful when you have a problem with GDB while doing
5161 remote debugging; you can make a recording of the session and send it
5162 to someone else, who can then recreate the problem.
5164 * Speedups for remote debugging
5166 GDB includes speedups for downloading and stepping MIPS systems using
5167 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5168 and more efficient S-record downloading.
5170 * Memory use reductions and statistics collection
5172 GDB now uses less memory and reports statistics about memory usage.
5173 Try the `maint print statistics' command, for example.
5175 *** Changes in GDB-4.15:
5177 * Psymtabs for XCOFF
5179 The symbol reader for AIX GDB now uses partial symbol tables. This
5180 can greatly improve startup time, especially for large executables.
5182 * Remote targets use caching
5184 Remote targets now use a data cache to speed up communication with the
5185 remote side. The data cache could lead to incorrect results because
5186 it doesn't know about volatile variables, thus making it impossible to
5187 debug targets which use memory mapped I/O devices. `set remotecache
5188 off' turns the the data cache off.
5190 * Remote targets may have threads
5192 The standard remote protocol now includes support for multiple threads
5193 in the target system, using new protocol commands 'H' and 'T'. See
5194 gdb/remote.c for details.
5198 If GDB is configured with `--enable-netrom', then it will include
5199 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5200 acts as though it is a bank of ROM on the target board, but you can
5201 write into it over the network. GDB's support consists only of
5202 support for fast loading into the emulated ROM; to debug, you must use
5203 another protocol, such as standard remote protocol. The usual
5204 sequence is something like
5206 target nrom <netrom-hostname>
5208 target remote <netrom-hostname>:1235
5212 GDB now includes support for the Apple Macintosh, as a host only. It
5213 may be run as either an MPW tool or as a standalone application, and
5214 it can debug through the serial port. All the usual GDB commands are
5215 available, but to the target command, you must supply "serial" as the
5216 device type instead of "/dev/ttyXX". See mpw-README in the main
5217 directory for more information on how to build. The MPW configuration
5218 scripts */mpw-config.in support only a few targets, and only the
5219 mips-idt-ecoff target has been tested.
5223 GDB configuration now uses autoconf. This is not user-visible,
5224 but does simplify configuration and building.
5228 GDB now supports hpux10.
5230 *** Changes in GDB-4.14:
5232 * New native configurations
5234 x86 FreeBSD i[345]86-*-freebsd
5235 x86 NetBSD i[345]86-*-netbsd
5236 NS32k NetBSD ns32k-*-netbsd
5237 Sparc NetBSD sparc-*-netbsd
5241 A29K VxWorks a29k-*-vxworks
5242 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5243 CPU32 EST-300 emulator m68*-*-est*
5244 PowerPC ELF powerpc-*-elf
5247 * Alpha OSF/1 support for procfs
5249 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5250 possible to attach to running processes. As the mounting of the /proc
5251 filesystem is optional on the Alpha, GDB automatically determines
5252 the availability of /proc during startup. This can lead to problems
5253 if /proc is unmounted after GDB has been started.
5255 * Arguments to user-defined commands
5257 User commands may accept up to 10 arguments separated by whitespace.
5258 Arguments are accessed within the user command via $arg0..$arg9. A
5261 print $arg0 + $arg1 + $arg2
5263 To execute the command use:
5266 Defines the command "adder" which prints the sum of its three arguments.
5267 Note the arguments are text substitutions, so they may reference variables,
5268 use complex expressions, or even perform inferior function calls.
5270 * New `if' and `while' commands
5272 This makes it possible to write more sophisticated user-defined
5273 commands. Both commands take a single argument, which is the
5274 expression to evaluate, and must be followed by the commands to
5275 execute, one per line, if the expression is nonzero, the list being
5276 terminated by the word `end'. The `if' command list may include an
5277 `else' word, which causes the following commands to be executed only
5278 if the expression is zero.
5280 * Fortran source language mode
5282 GDB now includes partial support for Fortran 77. It will recognize
5283 Fortran programs and can evaluate a subset of Fortran expressions, but
5284 variables and functions may not be handled correctly. GDB will work
5285 with G77, but does not yet know much about symbols emitted by other
5288 * Better HPUX support
5290 Most debugging facilities now work on dynamic executables for HPPAs
5291 running hpux9 or later. You can attach to running dynamically linked
5292 processes, but by default the dynamic libraries will be read-only, so
5293 for instance you won't be able to put breakpoints in them. To change
5294 that behavior do the following before running the program:
5300 This will cause the libraries to be mapped private and read-write.
5301 To revert to the normal behavior, do this:
5307 You cannot set breakpoints or examine data in the library until after
5308 the library is loaded if the function/data symbols do not have
5311 GDB can now also read debug symbols produced by the HP C compiler on
5312 HPPAs (sorry, no C++, Fortran or 68k support).
5314 * Target byte order now dynamically selectable
5316 You can choose which byte order to use with a target system, via the
5317 commands "set endian big" and "set endian little", and you can see the
5318 current setting by using "show endian". You can also give the command
5319 "set endian auto", in which case GDB will use the byte order
5320 associated with the executable. Currently, only embedded MIPS
5321 configurations support dynamic selection of target byte order.
5323 * New DOS host serial code
5325 This version uses DPMI interrupts to handle buffered I/O, so you
5326 no longer need to run asynctsr when debugging boards connected to
5329 *** Changes in GDB-4.13:
5331 * New "complete" command
5333 This lists all the possible completions for the rest of the line, if it
5334 were to be given as a command itself. This is intended for use by emacs.
5336 * Trailing space optional in prompt
5338 "set prompt" no longer adds a space for you after the prompt you set. This
5339 allows you to set a prompt which ends in a space or one that does not.
5341 * Breakpoint hit counts
5343 "info break" now displays a count of the number of times the breakpoint
5344 has been hit. This is especially useful in conjunction with "ignore"; you
5345 can ignore a large number of breakpoint hits, look at the breakpoint info
5346 to see how many times the breakpoint was hit, then run again, ignoring one
5347 less than that number, and this will get you quickly to the last hit of
5350 * Ability to stop printing at NULL character
5352 "set print null-stop" will cause GDB to stop printing the characters of
5353 an array when the first NULL is encountered. This is useful when large
5354 arrays actually contain only short strings.
5356 * Shared library breakpoints
5358 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5359 breakpoints in shared libraries before the executable is run.
5361 * Hardware watchpoints
5363 There is a new hardware breakpoint for the watch command for sparclite
5364 targets. See gdb/sparclite/hw_breakpoint.note.
5366 Hardware watchpoints are also now supported under GNU/Linux.
5370 Annotations have been added. These are for use with graphical interfaces,
5371 and are still experimental. Currently only gdba.el uses these.
5373 * Improved Irix 5 support
5375 GDB now works properly with Irix 5.2.
5377 * Improved HPPA support
5379 GDB now works properly with the latest GCC and GAS.
5381 * New native configurations
5383 Sequent PTX4 i[34]86-sequent-ptx4
5384 HPPA running OSF/1 hppa*-*-osf*
5385 Atari TT running SVR4 m68*-*-sysv4*
5386 RS/6000 LynxOS rs6000-*-lynxos*
5390 OS/9000 i[34]86-*-os9k
5391 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5394 * Hitachi SH7000 and E7000-PC ICE support
5396 There is now support for communicating with the Hitachi E7000-PC ICE.
5397 This is available automatically when GDB is configured for the SH.
5401 As usual, a variety of small fixes and improvements, both generic
5402 and configuration-specific. See the ChangeLog for more detail.
5404 *** Changes in GDB-4.12:
5406 * Irix 5 is now supported
5410 GDB-4.12 on the HPPA has a number of changes which make it unable
5411 to debug the output from the currently released versions of GCC and
5412 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5413 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5414 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5417 *** Changes in GDB-4.11:
5419 * User visible changes:
5423 The "set remotedebug" option is now consistent between the mips remote
5424 target, remote targets using the gdb-specific protocol, UDI (AMD's
5425 debug protocol for the 29k) and the 88k bug monitor. It is now an
5426 integer specifying a debug level (normally 0 or 1, but 2 means more
5427 debugging info for the mips target).
5429 * DEC Alpha native support
5431 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5432 debug info, but GDB works fairly well with the DEC compiler and should
5433 work with a future GCC release. See the README file for a few
5434 Alpha-specific notes.
5436 * Preliminary thread implementation
5438 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5440 * LynxOS native and target support for 386
5442 This release has been hosted on LynxOS 2.2, and also can be configured
5443 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5446 * Improvements in C++ mangling/demangling.
5448 This release has much better g++ debugging, specifically in name
5449 mangling/demangling, virtual function calls, print virtual table,
5450 call methods, ...etc.
5452 *** Changes in GDB-4.10:
5454 * User visible changes:
5456 Remote debugging using the GDB-specific (`target remote') protocol now
5457 supports the `load' command. This is only useful if you have some
5458 other way of getting the stub to the target system, and you can put it
5459 somewhere in memory where it won't get clobbered by the download.
5461 Filename completion now works.
5463 When run under emacs mode, the "info line" command now causes the
5464 arrow to point to the line specified. Also, "info line" prints
5465 addresses in symbolic form (as well as hex).
5467 All vxworks based targets now support a user settable option, called
5468 vxworks-timeout. This option represents the number of seconds gdb
5469 should wait for responses to rpc's. You might want to use this if
5470 your vxworks target is, perhaps, a slow software simulator or happens
5471 to be on the far side of a thin network line.
5475 This release contains support for using a DEC alpha as a GDB host for
5476 cross debugging. Native alpha debugging is not supported yet.
5479 *** Changes in GDB-4.9:
5483 This is the first GDB release which is accompanied by a matching testsuite.
5484 The testsuite requires installation of dejagnu, which should be available
5485 via ftp from most sites that carry GNU software.
5489 'Cfront' style demangling has had its name changed to 'ARM' style, to
5490 emphasize that it was written from the specifications in the C++ Annotated
5491 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5492 disclaimers, it still generated too much confusion with users attempting to
5493 use gdb with AT&T cfront.
5497 GDB now uses a standard remote interface to a simulator library.
5498 So far, the library contains simulators for the Zilog Z8001/2, the
5499 Hitachi H8/300, H8/500 and Super-H.
5501 * New targets supported
5503 H8/300 simulator h8300-hitachi-hms or h8300hms
5504 H8/500 simulator h8500-hitachi-hms or h8500hms
5505 SH simulator sh-hitachi-hms or sh
5506 Z8000 simulator z8k-zilog-none or z8ksim
5507 IDT MIPS board over serial line mips-idt-ecoff
5509 Cross-debugging to GO32 targets is supported. It requires a custom
5510 version of the i386-stub.c module which is integrated with the
5511 GO32 memory extender.
5513 * New remote protocols
5515 MIPS remote debugging protocol.
5517 * New source languages supported
5519 This version includes preliminary support for Chill, a Pascal like language
5520 used by telecommunications companies. Chill support is also being integrated
5521 into the GNU compiler, but we don't know when it will be publically available.
5524 *** Changes in GDB-4.8:
5526 * HP Precision Architecture supported
5528 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5529 version of this support was available as a set of patches from the
5530 University of Utah. GDB does not support debugging of programs
5531 compiled with the HP compiler, because HP will not document their file
5532 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5533 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5535 Many problems in the preliminary version have been fixed.
5537 * Faster and better demangling
5539 We have improved template demangling and fixed numerous bugs in the GNU style
5540 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5541 character types (wchar_t) are now supported. Demangling of each symbol is now
5542 only done once, and is cached when the symbol table for a file is read in.
5543 This results in a small increase in memory usage for C programs, a moderate
5544 increase in memory usage for C++ programs, and a fantastic speedup in
5547 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5548 from the specifications in the Annotated Reference Manual, which AT&T's
5549 compiler does not actually implement.
5551 * G++ multiple inheritance compiler problem
5553 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5554 inheritance lattices was reworked to properly discover ambiguities. We
5555 recently found an example which causes this new algorithm to fail in a
5556 very subtle way, producing bad debug information for those classes.
5557 The file 'gcc.patch' (in this directory) can be applied to gcc to
5558 circumvent the problem. A future GCC release will contain a complete
5561 The previous G++ debug info problem (mentioned below for the gdb-4.7
5562 release) is fixed in gcc version 2.3.2.
5564 * Improved configure script
5566 The `configure' script will now attempt to guess your system type if
5567 you don't supply a host system type. The old scheme of supplying a
5568 host system triplet is preferable over using this. All the magic is
5569 done in the new `config.guess' script. Examine it for details.
5571 We have also brought our configure script much more in line with the FSF's
5572 version. It now supports the --with-xxx options. In particular,
5573 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5574 The resulting GDB will not be able to read arbitrary object file formats --
5575 only the format ``expected'' to be used on the configured target system.
5576 We hope to make this the default in a future release.
5578 * Documentation improvements
5580 There's new internal documentation on how to modify GDB, and how to
5581 produce clean changes to the code. We implore people to read it
5582 before submitting changes.
5584 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5585 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5586 `info' files are also provided. To build `info' files from scratch,
5587 you will need the latest `makeinfo' release, which will be available in
5588 a future texinfo-X.Y release.
5590 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5591 We're not sure exactly which versions have this problem, but it has
5592 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5593 or better. If that isn't possible, there is a patch in
5594 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5595 around this problem.
5599 GDB now supports array constants that can be used in expressions typed in by
5600 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5601 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5604 The new directory `gdb/sparclite' contains a program that demonstrates
5605 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5607 * New native hosts supported
5609 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5610 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5612 * New targets supported
5614 AMD 29k family via UDI a29k-amd-udi or udi29k
5616 * New file formats supported
5618 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5619 HPUX core files, and SCO 3.2v2 core files.
5623 Attaching to processes now works again; thanks for the many bug reports.
5625 We have also stomped on a bunch of core dumps caused by
5626 printf_filtered("%s") problems.
5628 We eliminated a copyright problem on the rpc and ptrace header files
5629 for VxWorks, which was discovered at the last minute during the 4.7
5630 release. You should now be able to build a VxWorks GDB.
5632 You can now interrupt gdb while an attached process is running. This
5633 will cause the attached process to stop, and give control back to GDB.
5635 We fixed problems caused by using too many file descriptors
5636 for reading symbols from object files and libraries. This was
5637 especially a problem for programs that used many (~100) shared
5640 The `step' command now only enters a subroutine if there is line number
5641 information for the subroutine. Otherwise it acts like the `next'
5642 command. Previously, `step' would enter subroutines if there was
5643 any debugging information about the routine. This avoids problems
5644 when using `cc -g1' on MIPS machines.
5646 * Internal improvements
5648 GDB's internal interfaces have been improved to make it easier to support
5649 debugging of multiple languages in the future.
5651 GDB now uses a common structure for symbol information internally.
5652 Minimal symbols (derived from linkage symbols in object files), partial
5653 symbols (from a quick scan of debug information), and full symbols
5654 contain a common subset of information, making it easier to write
5655 shared code that handles any of them.
5657 * New command line options
5659 We now accept --silent as an alias for --quiet.
5663 The memory-mapped-malloc library is now licensed under the GNU Library
5664 General Public License.
5666 *** Changes in GDB-4.7:
5668 * Host/native/target split
5670 GDB has had some major internal surgery to untangle the support for
5671 hosts and remote targets. Now, when you configure GDB for a remote
5672 target, it will no longer load in all of the support for debugging
5673 local programs on the host. When fully completed and tested, this will
5674 ensure that arbitrary host/target combinations are possible.
5676 The primary conceptual shift is to separate the non-portable code in
5677 GDB into three categories. Host specific code is required any time GDB
5678 is compiled on that host, regardless of the target. Target specific
5679 code relates to the peculiarities of the target, but can be compiled on
5680 any host. Native specific code is everything else: it can only be
5681 built when the host and target are the same system. Child process
5682 handling and core file support are two common `native' examples.
5684 GDB's use of /proc for controlling Unix child processes is now cleaner.
5685 It has been split out into a single module under the `target_ops' vector,
5686 plus two native-dependent functions for each system that uses /proc.
5688 * New hosts supported
5690 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5691 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5692 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5694 * New targets supported
5696 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5697 68030 and CPU32 m68030-*-*, m68332-*-*
5699 * New native hosts supported
5701 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5702 (386bsd is not well tested yet)
5703 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5705 * New file formats supported
5707 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5708 supports reading of `a.out.adobe' object files, which are an a.out
5709 format extended with minimal information about multiple sections.
5713 `show copying' is the same as the old `info copying'.
5714 `show warranty' is the same as `info warrantee'.
5715 These were renamed for consistency. The old commands continue to work.
5717 `info handle' is a new alias for `info signals'.
5719 You can now define pre-command hooks, which attach arbitrary command
5720 scripts to any command. The commands in the hook will be executed
5721 prior to the user's command. You can also create a hook which will be
5722 executed whenever the program stops. See gdb.texinfo.
5726 We now deal with Cfront style name mangling, and can even extract type
5727 info from mangled symbols. GDB can automatically figure out which
5728 symbol mangling style your C++ compiler uses.
5730 Calling of methods and virtual functions has been improved as well.
5734 The crash that occured when debugging Sun Ansi-C compiled binaries is
5735 fixed. This was due to mishandling of the extra N_SO stabs output
5738 We also finally got Ultrix 4.2 running in house, and fixed core file
5739 support, with help from a dozen people on the net.
5741 John M. Farrell discovered that the reason that single-stepping was so
5742 slow on all of the Mips based platforms (primarily SGI and DEC) was
5743 that we were trying to demangle and lookup a symbol used for internal
5744 purposes on every instruction that was being stepped through. Changing
5745 the name of that symbol so that it couldn't be mistaken for a C++
5746 mangled symbol sped things up a great deal.
5748 Rich Pixley sped up symbol lookups in general by getting much smarter
5749 about when C++ symbol mangling is necessary. This should make symbol
5750 completion (TAB on the command line) much faster. It's not as fast as
5751 we'd like, but it's significantly faster than gdb-4.6.
5755 A new user controllable variable 'call_scratch_address' can
5756 specify the location of a scratch area to be used when GDB
5757 calls a function in the target. This is necessary because the
5758 usual method of putting the scratch area on the stack does not work
5759 in systems that have separate instruction and data spaces.
5761 We integrated changes to support the 29k UDI (Universal Debugger
5762 Interface), but discovered at the last minute that we didn't have all
5763 of the appropriate copyright paperwork. We are working with AMD to
5764 resolve this, and hope to have it available soon.
5768 We have sped up the remote serial line protocol, especially for targets
5769 with lots of registers. It now supports a new `expedited status' ('T')
5770 message which can be used in place of the existing 'S' status message.
5771 This allows the remote stub to send only the registers that GDB
5772 needs to make a quick decision about single-stepping or conditional
5773 breakpoints, eliminating the need to fetch the entire register set for
5774 each instruction being stepped through.
5776 The GDB remote serial protocol now implements a write-through cache for
5777 registers, only re-reading the registers if the target has run.
5779 There is also a new remote serial stub for SPARC processors. You can
5780 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5781 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5782 processor with a serial port.
5786 Configure.in files have become much easier to read and modify. A new
5787 `table driven' format makes it more obvious what configurations are
5788 supported, and what files each one uses.
5792 There is a new opcodes library which will eventually contain all of the
5793 disassembly routines and opcode tables. At present, it only contains
5794 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5795 disassembler (binutils/objdump) to share these routines.
5797 The libiberty library is now copylefted under the GNU Library General
5798 Public License. This allows more liberal use, and was done so libg++
5799 can use it. This makes no difference to GDB, since the Library License
5800 grants all the rights from the General Public License.
5804 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5805 reference to the stabs symbol info used by the debugger. It is (as far
5806 as we know) the only published document on this fascinating topic. We
5807 encourage you to read it, compare it to the stabs information on your
5808 system, and send improvements on the document in general (to
5809 bug-gdb@prep.ai.mit.edu).
5811 And, of course, many bugs have been fixed.
5814 *** Changes in GDB-4.6:
5816 * Better support for C++ function names
5818 GDB now accepts as input the "demangled form" of C++ overloaded function
5819 names and member function names, and can do command completion on such names
5820 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5821 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5822 Make use of command completion, it is your friend.
5824 GDB also now accepts a variety of C++ mangled symbol formats. They are
5825 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5826 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5827 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5828 for the list of formats.
5830 * G++ symbol mangling problem
5832 Recent versions of gcc have a bug in how they emit debugging information for
5833 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5834 directory) can be applied to gcc to fix the problem. Alternatively, if you
5835 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5836 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5837 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5840 * New 'maintenance' command
5842 All of the commands related to hacking GDB internals have been moved out of
5843 the main command set, and now live behind the 'maintenance' command. This
5844 can also be abbreviated as 'mt'. The following changes were made:
5846 dump-me -> maintenance dump-me
5847 info all-breakpoints -> maintenance info breakpoints
5848 printmsyms -> maintenance print msyms
5849 printobjfiles -> maintenance print objfiles
5850 printpsyms -> maintenance print psymbols
5851 printsyms -> maintenance print symbols
5853 The following commands are new:
5855 maintenance demangle Call internal GDB demangler routine to
5856 demangle a C++ link name and prints the result.
5857 maintenance print type Print a type chain for a given symbol
5859 * Change to .gdbinit file processing
5861 We now read the $HOME/.gdbinit file before processing the argv arguments
5862 (e.g. reading symbol files or core files). This allows global parameters to
5863 be set, which will apply during the symbol reading. The ./.gdbinit is still
5864 read after argv processing.
5866 * New hosts supported
5868 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5870 GNU/Linux support i386-unknown-linux or linux
5872 We are also including code to support the HP/PA running BSD and HPUX. This
5873 is almost guaranteed not to work, as we didn't have time to test or build it
5874 for this release. We are including it so that the more adventurous (or
5875 masochistic) of you can play with it. We also had major problems with the
5876 fact that the compiler that we got from HP doesn't support the -g option.
5879 * New targets supported
5881 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5883 * More smarts about finding #include files
5885 GDB now remembers the compilation directory for all include files, and for
5886 all files from which C is generated (like yacc and lex sources). This
5887 greatly improves GDB's ability to find yacc/lex sources, and include files,
5888 especially if you are debugging your program from a directory different from
5889 the one that contains your sources.
5891 We also fixed a bug which caused difficulty with listing and setting
5892 breakpoints in include files which contain C code. (In the past, you had to
5893 try twice in order to list an include file that you hadn't looked at before.)
5895 * Interesting infernals change
5897 GDB now deals with arbitrary numbers of sections, where the symbols for each
5898 section must be relocated relative to that section's landing place in the
5899 target's address space. This work was needed to support ELF with embedded
5900 stabs used by Solaris-2.0.
5902 * Bug fixes (of course!)
5904 There have been loads of fixes for the following things:
5905 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5906 i960, stabs, DOS(GO32), procfs, etc...
5908 See the ChangeLog for details.
5910 *** Changes in GDB-4.5:
5912 * New machines supported (host and target)
5914 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5916 SGI Irix-4.x mips-sgi-irix4 or iris4
5918 * New malloc package
5920 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5921 Mmalloc is capable of handling mutiple heaps of memory. It is also
5922 capable of saving a heap to a file, and then mapping it back in later.
5923 This can be used to greatly speedup the startup of GDB by using a
5924 pre-parsed symbol table which lives in a mmalloc managed heap. For
5925 more details, please read mmalloc/mmalloc.texi.
5929 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5930 'help info proc' for details.
5932 * MIPS ecoff symbol table format
5934 The code that reads MIPS symbol table format is now supported on all hosts.
5935 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5938 * File name changes for MS-DOS
5940 Many files in the config directories have been renamed to make it easier to
5941 support GDB on MS-DOSe systems (which have very restrictive file name
5942 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5943 environment) is close to working but has some remaining problems. Note
5944 that debugging of DOS programs is not supported, due to limitations
5945 in the ``operating system'', but it can be used to host cross-debugging.
5947 * Cross byte order fixes
5949 Many fixes have been made to support cross debugging of Sparc and MIPS
5950 targets from hosts whose byte order differs.
5952 * New -mapped and -readnow options
5954 If memory-mapped files are available on your system through the 'mmap'
5955 system call, you can use the -mapped option on the `file' or
5956 `symbol-file' commands to cause GDB to write the symbols from your
5957 program into a reusable file. If the program you are debugging is
5958 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5959 Future GDB debugging sessions will notice the presence of this file,
5960 and will quickly map in symbol information from it, rather than reading
5961 the symbol table from the executable program. Using the '-mapped'
5962 option in a GDB `file' or `symbol-file' command has the same effect as
5963 starting GDB with the '-mapped' command-line option.
5965 You can cause GDB to read the entire symbol table immediately by using
5966 the '-readnow' option with any of the commands that load symbol table
5967 information (or on the GDB command line). This makes the command
5968 slower, but makes future operations faster.
5970 The -mapped and -readnow options are typically combined in order to
5971 build a `fred.syms' file that contains complete symbol information.
5972 A simple GDB invocation to do nothing but build a `.syms' file for future
5975 gdb -batch -nx -mapped -readnow programname
5977 The `.syms' file is specific to the host machine on which GDB is run.
5978 It holds an exact image of GDB's internal symbol table. It cannot be
5979 shared across multiple host platforms.
5981 * longjmp() handling
5983 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5984 siglongjmp() without losing control. This feature has not yet been ported to
5985 all systems. It currently works on many 386 platforms, all MIPS-based
5986 platforms (SGI, DECstation, etc), and Sun3/4.
5990 Preliminary work has been put in to support the new Solaris OS from Sun. At
5991 this time, it can control and debug processes, but it is not capable of
5996 As always, many many bug fixes. The major areas were with g++, and mipsread.
5997 People using the MIPS-based platforms should experience fewer mysterious
5998 crashes and trashed symbol tables.
6000 *** Changes in GDB-4.4:
6002 * New machines supported (host and target)
6004 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6006 BSD Reno on Vax vax-dec-bsd
6007 Ultrix on Vax vax-dec-ultrix
6009 * New machines supported (target)
6011 AMD 29000 embedded, using EBMON a29k-none-none
6015 GDB continues to improve its handling of C++. `References' work better.
6016 The demangler has also been improved, and now deals with symbols mangled as
6017 per the Annotated C++ Reference Guide.
6019 GDB also now handles `stabs' symbol information embedded in MIPS
6020 `ecoff' symbol tables. Since the ecoff format was not easily
6021 extensible to handle new languages such as C++, this appeared to be a
6022 good way to put C++ debugging info into MIPS binaries. This option
6023 will be supported in the GNU C compiler, version 2, when it is
6026 * New features for SVR4
6028 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6029 shared libraries. Debugging dynamically linked programs should present
6030 only minor differences from debugging statically linked programs.
6032 The `info proc' command will print out information about any process
6033 on an SVR4 system (including the one you are debugging). At the moment,
6034 it prints the address mappings of the process.
6036 If you bring up GDB on another SVR4 system, please send mail to
6037 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6039 * Better dynamic linking support in SunOS
6041 Reading symbols from shared libraries which contain debugging symbols
6042 now works properly. However, there remain issues such as automatic
6043 skipping of `transfer vector' code during function calls, which
6044 make it harder to debug code in a shared library, than to debug the
6045 same code linked statically.
6049 GDB is now using the latest `getopt' routines from the FSF. This
6050 version accepts the -- prefix for options with long names. GDB will
6051 continue to accept the old forms (-option and +option) as well.
6052 Various single letter abbreviations for options have been explicity
6053 added to the option table so that they won't get overshadowed in the
6054 future by other options that begin with the same letter.
6058 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6059 Many assorted bugs have been handled. Many more remain to be handled.
6060 See the various ChangeLog files (primarily in gdb and bfd) for details.
6063 *** Changes in GDB-4.3:
6065 * New machines supported (host and target)
6067 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6068 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6069 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6071 * Almost SCO Unix support
6073 We had hoped to support:
6074 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6075 (except for core file support), but we discovered very late in the release
6076 that it has problems with process groups that render gdb unusable. Sorry
6077 about that. I encourage people to fix it and post the fixes.
6079 * Preliminary ELF and DWARF support
6081 GDB can read ELF object files on System V Release 4, and can handle
6082 debugging records for C, in DWARF format, in ELF files. This support
6083 is preliminary. If you bring up GDB on another SVR4 system, please
6084 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6089 GDB now uses the latest `readline' library. One user-visible change
6090 is that two tabs will list possible command completions, which previously
6091 required typing M-? (meta-question mark, or ESC ?).
6095 The `stepi' bug that many of you noticed has been squashed.
6096 Many bugs in C++ have been handled. Many more remain to be handled.
6097 See the various ChangeLog files (primarily in gdb and bfd) for details.
6099 * State of the MIPS world (in case you wondered):
6101 GDB can understand the symbol tables emitted by the compilers
6102 supplied by most vendors of MIPS-based machines, including DEC. These
6103 symbol tables are in a format that essentially nobody else uses.
6105 Some versions of gcc come with an assembler post-processor called
6106 mips-tfile. This program is required if you want to do source-level
6107 debugging of gcc-compiled programs. I believe FSF does not ship
6108 mips-tfile with gcc version 1, but it will eventually come with gcc
6111 Debugging of g++ output remains a problem. g++ version 1.xx does not
6112 really support it at all. (If you're lucky, you should be able to get
6113 line numbers and stack traces to work, but no parameters or local
6114 variables.) With some work it should be possible to improve the
6117 When gcc version 2 is released, you will have somewhat better luck.
6118 However, even then you will get confusing results for inheritance and
6121 We will eventually provide full debugging of g++ output on
6122 DECstations. This will probably involve some kind of stabs-in-ecoff
6123 encapulation, but the details have not been worked out yet.
6126 *** Changes in GDB-4.2:
6128 * Improved configuration
6130 Only one copy of `configure' exists now, and it is not self-modifying.
6131 Porting BFD is simpler.
6135 The `step' and `next' commands now only stop at the first instruction
6136 of a source line. This prevents the multiple stops that used to occur
6137 in switch statements, for-loops, etc. `Step' continues to stop if a
6138 function that has debugging information is called within the line.
6142 Lots of small bugs fixed. More remain.
6144 * New host supported (not target)
6146 Intel 386 PC clone running Mach i386-none-mach
6149 *** Changes in GDB-4.1:
6151 * Multiple source language support
6153 GDB now has internal scaffolding to handle several source languages.
6154 It determines the type of each source file from its filename extension,
6155 and will switch expression parsing and number formatting to match the
6156 language of the function in the currently selected stack frame.
6157 You can also specifically set the language to be used, with
6158 `set language c' or `set language modula-2'.
6162 GDB now has preliminary support for the GNU Modula-2 compiler,
6163 currently under development at the State University of New York at
6164 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6165 continue through the fall of 1991 and into 1992.
6167 Other Modula-2 compilers are currently not supported, and attempting to
6168 debug programs compiled with them will likely result in an error as the
6169 symbol table is read. Feel free to work on it, though!
6171 There are hooks in GDB for strict type checking and range checking,
6172 in the `Modula-2 philosophy', but they do not currently work.
6176 GDB can now write to executable and core files (e.g. patch
6177 a variable's value). You must turn this switch on, specify
6178 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6179 by assigning a new value to a variable. Modifications take
6182 * Automatic SunOS shared library reading
6184 When you run your program, GDB automatically determines where its
6185 shared libraries (if any) have been loaded, and reads their symbols.
6186 The `share' command is no longer needed. This also works when
6187 examining core files.
6191 You can specify the number of lines that the `list' command shows.
6194 * New machines supported (host and target)
6196 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6197 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6198 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6200 * New hosts supported (not targets)
6202 IBM RT/PC: romp-ibm-aix or rtpc
6204 * New targets supported (not hosts)
6206 AMD 29000 embedded with COFF a29k-none-coff
6207 AMD 29000 embedded with a.out a29k-none-aout
6208 Ultracomputer remote kernel debug a29k-nyu-kern
6210 * New remote interfaces
6216 *** Changes in GDB-4.0:
6220 Wide output is wrapped at good places to make the output more readable.
6222 Gdb now supports cross-debugging from a host machine of one type to a
6223 target machine of another type. Communication with the target system
6224 is over serial lines. The ``target'' command handles connecting to the
6225 remote system; the ``load'' command will download a program into the
6226 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6227 also supports debugging of realtime processes running under VxWorks,
6228 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6229 stub on the target system.
6231 New CPUs supported include the AMD 29000 and Intel 960.
6233 GDB now reads object files and symbol tables via a ``binary file''
6234 library, which allows a single copy of GDB to debug programs of multiple
6235 object file types such as a.out and coff.
6237 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6238 refcard.dvi and refcard.ps are available to format it).
6241 * Control-Variable user interface simplified
6243 All variables that control the operation of the debugger can be set
6244 by the ``set'' command, and displayed by the ``show'' command.
6246 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6247 ``Show prompt'' produces the response:
6248 Gdb's prompt is new-gdb=>.
6250 What follows are the NEW set commands. The command ``help set'' will
6251 print a complete list of old and new set commands. ``help set FOO''
6252 will give a longer description of the variable FOO. ``show'' will show
6253 all of the variable descriptions and their current settings.
6255 confirm on/off: Enables warning questions for operations that are
6256 hard to recover from, e.g. rerunning the program while
6257 it is already running. Default is ON.
6259 editing on/off: Enables EMACS style command line editing
6260 of input. Previous lines can be recalled with
6261 control-P, the current line can be edited with control-B,
6262 you can search for commands with control-R, etc.
6265 history filename NAME: NAME is where the gdb command history
6266 will be stored. The default is .gdb_history,
6267 or the value of the environment variable
6270 history size N: The size, in commands, of the command history. The
6271 default is 256, or the value of the environment variable
6274 history save on/off: If this value is set to ON, the history file will
6275 be saved after exiting gdb. If set to OFF, the
6276 file will not be saved. The default is OFF.
6278 history expansion on/off: If this value is set to ON, then csh-like
6279 history expansion will be performed on
6280 command line input. The default is OFF.
6282 radix N: Sets the default radix for input and output. It can be set
6283 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6284 in the current radix, so "set radix 10" is always a no-op.
6286 height N: This integer value is the number of lines on a page. Default
6287 is 24, the current `stty rows'' setting, or the ``li#''
6288 setting from the termcap entry matching the environment
6291 width N: This integer value is the number of characters on a line.
6292 Default is 80, the current `stty cols'' setting, or the ``co#''
6293 setting from the termcap entry matching the environment
6296 Note: ``set screensize'' is obsolete. Use ``set height'' and
6297 ``set width'' instead.
6299 print address on/off: Print memory addresses in various command displays,
6300 such as stack traces and structure values. Gdb looks
6301 more ``symbolic'' if you turn this off; it looks more
6302 ``machine level'' with it on. Default is ON.
6304 print array on/off: Prettyprint arrays. New convenient format! Default
6307 print demangle on/off: Print C++ symbols in "source" form if on,
6310 print asm-demangle on/off: Same, for assembler level printouts
6313 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6316 * Support for Epoch Environment.
6318 The epoch environment is a version of Emacs v18 with windowing. One
6319 new command, ``inspect'', is identical to ``print'', except that if you
6320 are running in the epoch environment, the value is printed in its own
6324 * Support for Shared Libraries
6326 GDB can now debug programs and core files that use SunOS shared libraries.
6327 Symbols from a shared library cannot be referenced
6328 before the shared library has been linked with the program (this
6329 happens after you type ``run'' and before the function main() is entered).
6330 At any time after this linking (including when examining core files
6331 from dynamically linked programs), gdb reads the symbols from each
6332 shared library when you type the ``sharedlibrary'' command.
6333 It can be abbreviated ``share''.
6335 sharedlibrary REGEXP: Load shared object library symbols for files
6336 matching a unix regular expression. No argument
6337 indicates to load symbols for all shared libraries.
6339 info sharedlibrary: Status of loaded shared libraries.
6344 A watchpoint stops execution of a program whenever the value of an
6345 expression changes. Checking for this slows down execution
6346 tremendously whenever you are in the scope of the expression, but is
6347 quite useful for catching tough ``bit-spreader'' or pointer misuse
6348 problems. Some machines such as the 386 have hardware for doing this
6349 more quickly, and future versions of gdb will use this hardware.
6351 watch EXP: Set a watchpoint (breakpoint) for an expression.
6353 info watchpoints: Information about your watchpoints.
6355 delete N: Deletes watchpoint number N (same as breakpoints).
6356 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6357 enable N: Re-enables watchpoint number N (same as breakpoints).
6360 * C++ multiple inheritance
6362 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6365 * C++ exception handling
6367 Gdb now supports limited C++ exception handling. Besides the existing
6368 ability to breakpoint on an exception handler, gdb can breakpoint on
6369 the raising of an exception (before the stack is peeled back to the
6372 catch FOO: If there is a FOO exception handler in the dynamic scope,
6373 set a breakpoint to catch exceptions which may be raised there.
6374 Multiple exceptions (``catch foo bar baz'') may be caught.
6376 info catch: Lists all exceptions which may be caught in the
6377 current stack frame.
6380 * Minor command changes
6382 The command ``call func (arg, arg, ...)'' now acts like the print
6383 command, except it does not print or save a value if the function's result
6384 is void. This is similar to dbx usage.
6386 The ``up'' and ``down'' commands now always print the frame they end up
6387 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6388 frames without printing.
6390 * New directory command
6392 'dir' now adds directories to the FRONT of the source search path.
6393 The path starts off empty. Source files that contain debug information
6394 about the directory in which they were compiled can be found even
6395 with an empty path; Sun CC and GCC include this information. If GDB can't
6396 find your source file in the current directory, type "dir .".
6398 * Configuring GDB for compilation
6400 For normal use, type ``./configure host''. See README or gdb.texinfo
6403 GDB now handles cross debugging. If you are remotely debugging between
6404 two different machines, type ``./configure host -target=targ''.
6405 Host is the machine where GDB will run; targ is the machine
6406 where the program that you are debugging will run.
projects / binutils-gdb.git / blob