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
25 previous releases. See also $_gthread below.
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 * In commands that accept a list of thread IDs, you can now refer to
38 all threads of an inferior using a star wildcard. GDB accepts
39 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
40 refer to all threads of the current inferior. For example, "info
43 * You can use "info threads -gid" to display the global thread ID of
46 * The new convenience variable $_gthread holds the global number of
49 * The new convenience variable $_inferior holds the number of the
52 * GDB now displays the ID and name of the thread that hit a breakpoint
53 or received a signal, if your program is multi-threaded. For
56 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
57 Thread 1 "main" received signal SIGINT, Interrupt.
59 * Record btrace now supports non-stop mode.
61 * Support for tracepoints on aarch64-linux was added in GDBserver.
63 * The 'record instruction-history' command now indicates speculative execution
64 when using the Intel Processor Trace recording format.
66 * GDB now allows users to specify explicit locations, bypassing
67 the linespec parser. This feature is also available to GDB/MI
70 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
71 GDB now is able to debug both AArch64 applications and ARM applications
74 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
75 including JIT compiling fast tracepoint's conditional expression bytecode
78 * GDB now supports displaced stepping on AArch64 GNU/Linux.
80 * "info threads", "info inferiors", "info display", "info checkpoints"
81 and "maint info program-spaces" now list the corresponding items in
82 ascending ID order, for consistency with all other "info" commands.
84 * In Ada, the overloads selection menu has been enhanced to display the
85 parameter types and the return types for the matching overloaded subprograms.
89 maint set target-non-stop (on|off|auto)
90 maint show target-non-stop
91 Control whether GDB targets always operate in non-stop mode even if
92 "set non-stop" is "off". The default is "auto", meaning non-stop
93 mode is enabled if supported by the target.
96 maint show bfd-sharing
97 Control the reuse of bfd objects.
101 Control display of debugging info regarding bfd caching.
103 set remote multiprocess-extensions-packet
104 show remote multiprocess-extensions-packet
105 Set/show the use of the remote protocol multiprocess extensions.
107 set remote thread-events
108 show remote thread-events
109 Set/show the use of thread create/exit events.
111 set ada print-signatures on|off
112 show ada print-signatures"
113 Control whether parameter types and return types are displayed in overloads
114 selection menus. It is activaled (@code{on}) by default.
116 * The "disassemble" command accepts a new modifier: /s.
117 It prints mixed source+disassembly like /m with two differences:
118 - disassembled instructions are now printed in program order, and
119 - and source for all relevant files is now printed.
120 The "/m" option is now considered deprecated: its "source-centric"
121 output hasn't proved useful in practice.
123 * The "record instruction-history" command accepts a new modifier: /s.
124 It behaves exactly like /m and prints mixed source+disassembly.
126 * The "set scheduler-locking" command supports a new mode "replay".
127 It behaves like "off" in record mode and like "on" in replay mode.
129 * Support for various ROM monitors has been removed:
131 target dbug dBUG ROM monitor for Motorola ColdFire
132 target picobug Motorola picobug monitor
133 target dink32 DINK32 ROM monitor for PowerPC
134 target m32r Renesas M32R/D ROM monitor
135 target mon2000 mon2000 ROM monitor
136 target ppcbug PPCBUG ROM monitor for PowerPC
138 * Support for reading/writing memory and extracting values on architectures
139 whose memory is addressable in units of any integral multiple of 8 bits.
144 Indicates that an exec system call was executed.
146 exec-events feature in qSupported
147 The qSupported packet allows GDB to request support for exec
148 events using the new 'gdbfeature' exec-event, and the qSupported
149 response can contain the corresponding 'stubfeature'. Set and
150 show commands can be used to display whether these features are enabled.
153 Equivalent to interrupting with the ^C character, but works in
156 thread created stop reason (T05 create:...)
157 Indicates that the thread was just created and is stopped at entry.
159 thread exit stop reply (w exitcode;tid)
160 Indicates that the thread has terminated.
163 Enables/disables thread create and exit event reporting. For
164 example, this is used in non-stop mode when GDB stops a set of
165 threads and synchronously waits for the their corresponding stop
166 replies. Without exit events, if one of the threads exits, GDB
167 would hang forever not knowing that it should no longer expect a
168 stop for that same thread.
172 Indicates that there are no resumed threads left in the target (all
173 threads are stopped). The remote stub reports support for this stop
174 reply to GDB's qSupported query.
176 QCatchSyscalls:1 [;SYSNO]...
178 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
179 catching syscalls from the inferior process.
181 syscall_entry stop reason
182 Indicates that a syscall was just called.
184 syscall_return stop reason
185 Indicates that a syscall just returned.
187 QCatchSyscalls:1 in qSupported
188 The qSupported packet may now include QCatchSyscalls:1 in the reply
189 to indicate support for catching syscalls.
191 * Extended-remote exec events
193 ** GDB now has support for exec events on extended-remote Linux targets.
194 For such targets with Linux kernels 2.5.46 and later, this enables
195 follow-exec-mode and exec catchpoints.
197 set remote exec-event-feature-packet
198 show remote exec-event-feature-packet
199 Set/show the use of the remote exec event feature.
201 * Thread names in remote protocol
203 The reply to qXfer:threads:read may now include a name attribute for each
206 * Target remote mode fork and exec events
208 ** GDB now has support for fork and exec events on target remote mode
209 Linux targets. For such targets with Linux kernels 2.5.46 and later,
210 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
211 fork and exec catchpoints.
213 * Remote syscall events
215 ** GDB now has support for catch syscall on remote Linux targets,
216 currently enabled on x86/x86_64 architectures.
218 set remote catch-syscall-packet
219 show remote catch-syscall-packet
220 Set/show the use of the remote catch syscall feature.
224 ** The -var-set-format command now accepts the zero-hexadecimal
225 format. It outputs data in hexadecimal format with zero-padding on the
230 ** gdb.InferiorThread objects have a new attribute "global_num",
231 which refers to the thread's global thread ID. The existing
232 "num" attribute now refers to the thread's per-inferior number.
233 See "Per-inferior thread numbers" above.
234 ** gdb.InferiorThread objects have a new attribute "inferior", which
235 is the Inferior object the thread belongs to.
237 *** Changes in GDB 7.10
239 * Support for process record-replay and reverse debugging on aarch64*-linux*
240 targets has been added. GDB now supports recording of A64 instruction set
241 including advance SIMD instructions.
243 * Support for Sun's version of the "stabs" debug file format has been removed.
245 * GDB now honors the content of the file /proc/PID/coredump_filter
246 (PID is the process ID) on GNU/Linux systems. This file can be used
247 to specify the types of memory mappings that will be included in a
248 corefile. For more information, please refer to the manual page of
249 "core(5)". GDB also has a new command: "set use-coredump-filter
250 on|off". It allows to set whether GDB will read the content of the
251 /proc/PID/coredump_filter file when generating a corefile.
253 * The "info os" command on GNU/Linux can now display information on
255 "info os cpus" Listing of all cpus/cores on the system
257 * GDB has two new commands: "set serial parity odd|even|none" and
258 "show serial parity". These allows to set or show parity for the
261 * The "info source" command now displays the producer string if it was
262 present in the debug info. This typically includes the compiler version
263 and may include things like its command line arguments.
265 * The "info dll", an alias of the "info sharedlibrary" command,
266 is now available on all platforms.
268 * Directory names supplied to the "set sysroot" commands may be
269 prefixed with "target:" to tell GDB to access shared libraries from
270 the target system, be it local or remote. This replaces the prefix
271 "remote:". The default sysroot has been changed from "" to
272 "target:". "remote:" is automatically converted to "target:" for
273 backward compatibility.
275 * The system root specified by "set sysroot" will be prepended to the
276 filename of the main executable (if reported to GDB as absolute by
277 the operating system) when starting processes remotely, and when
278 attaching to already-running local or remote processes.
280 * GDB now supports automatic location and retrieval of executable
281 files from remote targets. Remote debugging can now be initiated
282 using only a "target remote" or "target extended-remote" command
283 (no "set sysroot" or "file" commands are required). See "New remote
286 * The "dump" command now supports verilog hex format.
288 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
290 * On GNU/Linux, GDB and gdbserver are now able to access executable
291 and shared library files without a "set sysroot" command when
292 attaching to processes running in different mount namespaces from
293 the debugger. This makes it possible to attach to processes in
294 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
295 See "New remote packets" below.
297 * The "tui reg" command now provides completion for all of the
298 available register groups, including target specific groups.
300 * The HISTSIZE environment variable is no longer read when determining
301 the size of GDB's command history. GDB now instead reads the dedicated
302 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
303 disables truncation of command history. Non-numeric values of GDBHISTSIZE
308 ** Memory ports can now be unbuffered.
312 ** gdb.Objfile objects have a new attribute "username",
313 which is the name of the objfile as specified by the user,
314 without, for example, resolving symlinks.
315 ** You can now write frame unwinders in Python.
316 ** gdb.Type objects have a new method "optimized_out",
317 returning optimized out gdb.Value instance of this type.
318 ** gdb.Value objects have new methods "reference_value" and
319 "const_value" which return a reference to the value and a
320 "const" version of the value respectively.
324 maint print symbol-cache
325 Print the contents of the symbol cache.
327 maint print symbol-cache-statistics
328 Print statistics of symbol cache usage.
330 maint flush-symbol-cache
331 Flush the contents of the symbol cache.
335 Start branch trace recording using Branch Trace Store (BTS) format.
338 Evaluate expression by using the compiler and print result.
342 Explicit commands for enabling and disabling tui mode.
345 set mpx bound on i386 and amd64
346 Support for bound table investigation on Intel MPX enabled applications.
350 Start branch trace recording using Intel Processor Trace format.
353 Print information about branch tracing internals.
355 maint btrace packet-history
356 Print the raw branch tracing data.
358 maint btrace clear-packet-history
359 Discard the stored raw branch tracing data.
362 Discard all branch tracing data. It will be fetched and processed
363 anew by the next "record" command.
368 Renamed from "set debug dwarf2-die".
370 Renamed from "show debug dwarf2-die".
373 Renamed from "set debug dwarf2-read".
374 show debug dwarf-read
375 Renamed from "show debug dwarf2-read".
377 maint set dwarf always-disassemble
378 Renamed from "maint set dwarf2 always-disassemble".
379 maint show dwarf always-disassemble
380 Renamed from "maint show dwarf2 always-disassemble".
382 maint set dwarf max-cache-age
383 Renamed from "maint set dwarf2 max-cache-age".
384 maint show dwarf max-cache-age
385 Renamed from "maint show dwarf2 max-cache-age".
388 show debug dwarf-line
389 Control display of debugging info regarding DWARF line processing.
393 Set the maximum number of candidates to be considered during
394 completion. The default value is 200. This limit allows GDB
395 to avoid generating large completion lists, the computation of
396 which can cause the debugger to become temporarily unresponsive.
398 set history remove-duplicates
399 show history remove-duplicates
400 Control the removal of duplicate history entries.
402 maint set symbol-cache-size
403 maint show symbol-cache-size
404 Control the size of the symbol cache.
406 set|show record btrace bts buffer-size
407 Set and show the size of the ring buffer used for branch tracing in
409 The obtained size may differ from the requested size. Use "info
410 record" to see the obtained buffer size.
412 set debug linux-namespaces
413 show debug linux-namespaces
414 Control display of debugging info regarding Linux namespaces.
416 set|show record btrace pt buffer-size
417 Set and show the size of the ring buffer used for branch tracing in
418 Intel Processor Trace format.
419 The obtained size may differ from the requested size. Use "info
420 record" to see the obtained buffer size.
422 maint set|show btrace pt skip-pad
423 Set and show whether PAD packets are skipped when computing the
426 * The command 'thread apply all' can now support new option '-ascending'
427 to call its specified command for all threads in ascending order.
429 * Python/Guile scripting
431 ** GDB now supports auto-loading of Python/Guile scripts contained in the
432 special section named `.debug_gdb_scripts'.
436 qXfer:btrace-conf:read
437 Return the branch trace configuration for the current thread.
439 Qbtrace-conf:bts:size
440 Set the requested ring buffer size for branch tracing in BTS format.
443 Enable Intel Procesor Trace-based branch tracing for the current
444 process. The remote stub reports support for this packet to GDB's
448 Set the requested ring buffer size for branch tracing in Intel Processor
452 Indicates a memory breakpoint instruction was executed, irrespective
453 of whether it was GDB that planted the breakpoint or the breakpoint
454 is hardcoded in the program. This is required for correct non-stop
458 Indicates the target stopped for a hardware breakpoint. This is
459 required for correct non-stop mode operation.
462 Return information about files on the remote system.
465 Return the full absolute name of the file that was executed to
466 create a process running on the remote system.
469 Select the filesystem on which vFile: operations with filename
470 arguments will operate. This is required for GDB to be able to
471 access files on remote targets where the remote stub does not
472 share a common filesystem with the inferior(s).
475 Indicates that a fork system call was executed.
478 Indicates that a vfork system call was executed.
480 vforkdone stop reason
481 Indicates that a vfork child of the specified process has executed
482 an exec or exit, allowing the vfork parent to resume execution.
484 fork-events and vfork-events features in qSupported
485 The qSupported packet allows GDB to request support for fork and
486 vfork events using new 'gdbfeatures' fork-events and vfork-events,
487 and the qSupported response can contain the corresponding
488 'stubfeatures'. Set and show commands can be used to display
489 whether these features are enabled.
491 * Extended-remote fork events
493 ** GDB now has support for fork events on extended-remote Linux
494 targets. For targets with Linux kernels 2.5.60 and later, this
495 enables follow-fork-mode and detach-on-fork for both fork and
496 vfork, as well as fork and vfork catchpoints.
498 * The info record command now shows the recording format and the
499 branch tracing configuration for the current thread when using
500 the btrace record target.
501 For the BTS format, it shows the ring buffer size.
503 * GDB now has support for DTrace USDT (Userland Static Defined
504 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
506 * GDB now supports access to vector registers on S/390 GNU/Linux
509 * Removed command line options
511 -xdb HP-UX XDB compatibility mode.
513 * Removed targets and native configurations
515 HP/PA running HP-UX hppa*-*-hpux*
516 Itanium running HP-UX ia64-*-hpux*
518 * New configure options
521 This configure option allows the user to build GDB with support for
522 Intel Processor Trace (default: auto). This requires libipt.
524 --with-libipt-prefix=PATH
525 Specify the path to the version of libipt that GDB should use.
526 $PATH/include should contain the intel-pt.h header and
527 $PATH/lib should contain the libipt.so library.
529 *** Changes in GDB 7.9.1
533 ** Xmethods can now specify a result type.
535 *** Changes in GDB 7.9
537 * GDB now supports hardware watchpoints on x86 GNU Hurd.
541 ** You can now access frame registers from Python scripts.
542 ** New attribute 'producer' for gdb.Symtab objects.
543 ** gdb.Objfile objects have a new attribute "progspace",
544 which is the gdb.Progspace object of the containing program space.
545 ** gdb.Objfile objects have a new attribute "owner".
546 ** gdb.Objfile objects have a new attribute "build_id",
547 which is the build ID generated when the file was built.
548 ** gdb.Objfile objects have a new method "add_separate_debug_file".
549 ** A new event "gdb.clear_objfiles" has been added, triggered when
550 selecting a new file to debug.
551 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
552 ** New function gdb.lookup_objfile.
554 New events which are triggered when GDB modifies the state of the
557 ** gdb.events.inferior_call_pre: Function call is about to be made.
558 ** gdb.events.inferior_call_post: Function call has just been made.
559 ** gdb.events.memory_changed: A memory location has been altered.
560 ** gdb.events.register_changed: A register has been altered.
562 * New Python-based convenience functions:
564 ** $_caller_is(name [, number_of_frames])
565 ** $_caller_matches(regexp [, number_of_frames])
566 ** $_any_caller_is(name [, number_of_frames])
567 ** $_any_caller_matches(regexp [, number_of_frames])
569 * GDB now supports the compilation and injection of source code into
570 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
571 to compile the source code to object code, and if successful, inject
572 and execute that code within the current context of the inferior.
573 Currently the C language is supported. The commands used to
574 interface with this new feature are:
576 compile code [-raw|-r] [--] [source code]
577 compile file [-raw|-r] filename
581 demangle [-l language] [--] name
582 Demangle "name" in the specified language, or the current language
583 if elided. This command is renamed from the "maint demangle" command.
584 The latter is kept as a no-op to avoid "maint demangle" being interpreted
585 as "maint demangler-warning".
587 queue-signal signal-name-or-number
588 Queue a signal to be delivered to the thread when it is resumed.
590 add-auto-load-scripts-directory directory
591 Add entries to the list of directories from which to load auto-loaded
594 maint print user-registers
595 List all currently available "user" registers.
597 compile code [-r|-raw] [--] [source code]
598 Compile, inject, and execute in the inferior the executable object
599 code produced by compiling the provided source code.
601 compile file [-r|-raw] filename
602 Compile and inject into the inferior the executable object code
603 produced by compiling the source code stored in the filename
606 * On resume, GDB now always passes the signal the program had stopped
607 for to the thread the signal was sent to, even if the user changed
608 threads before resuming. Previously GDB would often (but not
609 always) deliver the signal to the thread that happens to be current
612 * Conversely, the "signal" command now consistently delivers the
613 requested signal to the current thread. GDB now asks for
614 confirmation if the program had stopped for a signal and the user
615 switched threads meanwhile.
617 * "breakpoint always-inserted" modes "off" and "auto" merged.
619 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
620 won't remove breakpoints from the target until all threads stop,
621 even in non-stop mode. The "auto" mode has been removed, and "off"
622 is now the default mode.
626 set debug symbol-lookup
627 show debug symbol-lookup
628 Control display of debugging info regarding symbol lookup.
632 ** The -list-thread-groups command outputs an exit-code field for
633 inferiors that have exited.
637 MIPS SDE mips*-sde*-elf*
641 Support for these obsolete configurations has been removed.
643 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
644 SGI Irix-5.x mips-*-irix5*
645 SGI Irix-6.x mips-*-irix6*
646 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
647 VAX running Ultrix vax-*-ultrix*
649 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
650 and "assf"), have been removed. Use the "sharedlibrary" command, or
651 its alias "share", instead.
653 *** Changes in GDB 7.8
655 * New command line options
658 This is an alias for the --data-directory option.
660 * GDB supports printing and modifying of variable length automatic arrays
661 as specified in ISO C99.
663 * The ARM simulator now supports instruction level tracing
664 with or without disassembly.
668 GDB now has support for scripting using Guile. Whether this is
669 available is determined at configure time.
670 Guile version 2.0 or greater is required.
671 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
673 * New commands (for set/show, see "New options" below)
677 Invoke CODE by passing it to the Guile interpreter.
681 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
683 info auto-load guile-scripts [regexp]
684 Print the list of automatically loaded Guile scripts.
686 * The source command is now capable of sourcing Guile scripts.
687 This feature is dependent on the debugger being built with Guile support.
691 set print symbol-loading (off|brief|full)
692 show print symbol-loading
693 Control whether to print informational messages when loading symbol
694 information for a file. The default is "full", but when debugging
695 programs with large numbers of shared libraries the amount of output
698 set guile print-stack (none|message|full)
699 show guile print-stack
700 Show a stack trace when an error is encountered in a Guile script.
702 set auto-load guile-scripts (on|off)
703 show auto-load guile-scripts
704 Control auto-loading of Guile script files.
706 maint ada set ignore-descriptive-types (on|off)
707 maint ada show ignore-descriptive-types
708 Control whether the debugger should ignore descriptive types in Ada
709 programs. The default is not to ignore the descriptive types. See
710 the user manual for more details on descriptive types and the intended
711 usage of this option.
713 set auto-connect-native-target
715 Control whether GDB is allowed to automatically connect to the
716 native target for the run, attach, etc. commands when not connected
717 to any target yet. See also "target native" below.
719 set record btrace replay-memory-access (read-only|read-write)
720 show record btrace replay-memory-access
721 Control what memory accesses are allowed during replay.
723 maint set target-async (on|off)
724 maint show target-async
725 This controls whether GDB targets operate in synchronous or
726 asynchronous mode. Normally the default is asynchronous, if it is
727 available; but this can be changed to more easily debug problems
728 occurring only in synchronous mode.
730 set mi-async (on|off)
732 Control whether MI asynchronous mode is preferred. This supersedes
733 "set target-async" of previous GDB versions.
735 * "set target-async" is deprecated as a CLI option and is now an alias
736 for "set mi-async" (only puts MI into async mode).
738 * Background execution commands (e.g., "c&", "s&", etc.) are now
739 possible ``out of the box'' if the target supports them. Previously
740 the user would need to explicitly enable the possibility with the
741 "set target-async on" command.
743 * New features in the GDB remote stub, GDBserver
745 ** New option --debug-format=option1[,option2,...] allows one to add
746 additional text to each output. At present only timestamps
747 are supported: --debug-format=timestamps.
748 Timestamps can also be turned on with the
749 "monitor set debug-format timestamps" command from GDB.
751 * The 'record instruction-history' command now starts counting instructions
752 at one. This also affects the instruction ranges reported by the
753 'record function-call-history' command when given the /i modifier.
755 * The command 'record function-call-history' supports a new modifier '/c' to
756 indent the function names based on their call stack depth.
757 The fields for the '/i' and '/l' modifier have been reordered.
758 The source line range is now prefixed with 'at'.
759 The instruction range is now prefixed with 'inst'.
760 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
761 "record instruction-history" and "list" commands.
763 * The ranges given as arguments to the 'record function-call-history' and
764 'record instruction-history' commands are now inclusive.
766 * The btrace record target now supports the 'record goto' command.
767 For locations inside the execution trace, the back trace is computed
768 based on the information stored in the execution trace.
770 * The btrace record target supports limited reverse execution and replay.
771 The target does not record data and therefore does not allow reading
774 * The "catch syscall" command now works on s390*-linux* targets.
776 * The "compare-sections" command is no longer specific to target
777 remote. It now works with all targets.
779 * All native targets are now consistently called "native".
780 Consequently, the "target child", "target GNU", "target djgpp",
781 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
782 commands have been replaced with "target native". The QNX/NTO port
783 leaves the "procfs" target in place and adds a "native" target for
784 consistency with other ports. The impact on users should be minimal
785 as these commands previously either throwed an error, or were
786 no-ops. The target's name is visible in the output of the following
787 commands: "help target", "info target", "info files", "maint print
790 * The "target native" command now connects to the native target. This
791 can be used to launch native programs even when "set
792 auto-connect-native-target" is set to off.
794 * GDB now supports access to Intel MPX registers on GNU/Linux.
796 * Support for Intel AVX-512 registers on GNU/Linux.
797 Support displaying and modifying Intel AVX-512 registers
798 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
802 qXfer:btrace:read's annex
803 The qXfer:btrace:read packet supports a new annex 'delta' to read
804 branch trace incrementally.
808 ** Valid Python operations on gdb.Value objects representing
809 structs/classes invoke the corresponding overloaded operators if
811 ** New `Xmethods' feature in the Python API. Xmethods are
812 additional methods or replacements for existing methods of a C++
813 class. This feature is useful for those cases where a method
814 defined in C++ source code could be inlined or optimized out by
815 the compiler, making it unavailable to GDB.
818 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
820 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
821 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
822 its alias "share", instead.
824 * The commands "set remotebaud" and "show remotebaud" are no longer
825 supported. Use "set serial baud" and "show serial baud" (respectively)
830 ** A new option "-gdb-set mi-async" replaces "-gdb-set
831 target-async". The latter is left as a deprecated alias of the
832 former for backward compatibility. If the target supports it,
833 CLI background execution commands are now always possible by
834 default, independently of whether the frontend stated a
835 preference for asynchronous execution with "-gdb-set mi-async".
836 Previously "-gdb-set target-async off" affected both MI execution
837 commands and CLI execution commands.
839 *** Changes in GDB 7.7
841 * Improved support for process record-replay and reverse debugging on
842 arm*-linux* targets. Support for thumb32 and syscall instruction
843 recording has been added.
845 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
847 * GDB now supports Fission DWP file format version 2.
848 http://gcc.gnu.org/wiki/DebugFission
850 * New convenience function "$_isvoid", to check whether an expression
851 is void. A void expression is an expression where the type of the
852 result is "void". For example, some convenience variables may be
853 "void" when evaluated (e.g., "$_exitcode" before the execution of
854 the program being debugged; or an undefined convenience variable).
855 Another example, when calling a function whose return type is
858 * The "maintenance print objfiles" command now takes an optional regexp.
860 * The "catch syscall" command now works on arm*-linux* targets.
862 * GDB now consistently shows "<not saved>" when printing values of
863 registers the debug info indicates have not been saved in the frame
864 and there's nowhere to retrieve them from
865 (callee-saved/call-clobbered registers):
870 (gdb) info registers rax
873 Before, the former would print "<optimized out>", and the latter
874 "*value not available*".
876 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
881 ** Frame filters and frame decorators have been added.
882 ** Temporary breakpoints are now supported.
883 ** Line tables representation has been added.
884 ** New attribute 'parent_type' for gdb.Field objects.
885 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
886 ** New attribute 'name' for gdb.Type objects.
890 Nios II ELF nios2*-*-elf
891 Nios II GNU/Linux nios2*-*-linux
892 Texas Instruments MSP430 msp430*-*-elf
894 * Removed native configurations
896 Support for these a.out NetBSD and OpenBSD obsolete configurations has
897 been removed. ELF variants of these configurations are kept supported.
899 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
900 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
901 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
902 i[34567]86-*-openbsd3.[0-3]
903 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
904 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
905 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
909 Like "catch throw", but catches a re-thrown exception.
911 Renamed from old "maint check-symtabs".
913 Perform consistency checks on symtabs.
915 Expand symtabs matching an optional regexp.
918 Display the details of GDB configure-time options.
920 maint set|show per-command
921 maint set|show per-command space
922 maint set|show per-command time
923 maint set|show per-command symtab
924 Enable display of per-command gdb resource usage.
926 remove-symbol-file FILENAME
927 remove-symbol-file -a ADDRESS
928 Remove a symbol file added via add-symbol-file. The file to remove
929 can be identified by its filename or by an address that lies within
930 the boundaries of this symbol file in memory.
933 info exceptions REGEXP
934 Display the list of Ada exceptions defined in the program being
935 debugged. If provided, only the exceptions whose names match REGEXP
940 set debug symfile off|on
942 Control display of debugging info regarding reading symbol files and
943 symbol tables within those files
945 set print raw frame-arguments
946 show print raw frame-arguments
947 Set/show whether to print frame arguments in raw mode,
948 disregarding any defined pretty-printers.
950 set remote trace-status-packet
951 show remote trace-status-packet
952 Set/show the use of remote protocol qTStatus packet.
956 Control display of debugging messages related to Nios II targets.
960 Control whether target-assisted range stepping is enabled.
962 set startup-with-shell
963 show startup-with-shell
964 Specifies whether Unix child processes are started via a shell or
969 Use the target memory cache for accesses to the code segment. This
970 improves performance of remote debugging (particularly disassembly).
972 * You can now use a literal value 'unlimited' for options that
973 interpret 0 or -1 as meaning "unlimited". E.g., "set
974 trace-buffer-size unlimited" is now an alias for "set
975 trace-buffer-size -1" and "set height unlimited" is now an alias for
978 * The "set debug symtab-create" debugging option of GDB has been changed to
979 accept a verbosity level. 0 means "off", 1 provides basic debugging
980 output, and values of 2 or greater provides more verbose output.
982 * New command-line options
984 Display the details of GDB configure-time options.
986 * The command 'tsave' can now support new option '-ctf' to save trace
987 buffer in Common Trace Format.
989 * Newly installed $prefix/bin/gcore acts as a shell interface for the
992 * GDB now implements the the C++ 'typeid' operator.
994 * The new convenience variable $_exception holds the exception being
995 thrown or caught at an exception-related catchpoint.
997 * The exception-related catchpoints, like "catch throw", now accept a
998 regular expression which can be used to filter exceptions by type.
1000 * The new convenience variable $_exitsignal is automatically set to
1001 the terminating signal number when the program being debugged dies
1002 due to an uncaught signal.
1006 ** All MI commands now accept an optional "--language" option.
1007 Support for this feature can be verified by using the "-list-features"
1008 command, which should contain "language-option".
1010 ** The new command -info-gdb-mi-command allows the user to determine
1011 whether a GDB/MI command is supported or not.
1013 ** The "^error" result record returned when trying to execute an undefined
1014 GDB/MI command now provides a variable named "code" whose content is the
1015 "undefined-command" error code. Support for this feature can be verified
1016 by using the "-list-features" command, which should contain
1017 "undefined-command-error-code".
1019 ** The -trace-save MI command can optionally save trace buffer in Common
1022 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1024 ** The command -data-list-register-values now accepts an optional
1025 "--skip-unavailable" option. When used, only the available registers
1028 ** The new command -trace-frame-collected dumps collected variables,
1029 computed expressions, tvars, memory and registers in a traceframe.
1031 ** The commands -stack-list-locals, -stack-list-arguments and
1032 -stack-list-variables now accept an option "--skip-unavailable".
1033 When used, only the available locals or arguments are displayed.
1035 ** The -exec-run command now accepts an optional "--start" option.
1036 When used, the command follows the same semantics as the "start"
1037 command, stopping the program's execution at the start of its
1038 main subprogram. Support for this feature can be verified using
1039 the "-list-features" command, which should contain
1040 "exec-run-start-option".
1042 ** The new commands -catch-assert and -catch-exceptions insert
1043 catchpoints stopping the program when Ada exceptions are raised.
1045 ** The new command -info-ada-exceptions provides the equivalent of
1046 the new "info exceptions" command.
1048 * New system-wide configuration scripts
1049 A GDB installation now provides scripts suitable for use as system-wide
1050 configuration scripts for the following systems:
1054 * GDB now supports target-assigned range stepping with remote targets.
1055 This improves the performance of stepping source lines by reducing
1056 the number of control packets from/to GDB. See "New remote packets"
1059 * GDB now understands the element 'tvar' in the XML traceframe info.
1060 It has the id of the collected trace state variables.
1062 * On S/390 targets that provide the transactional-execution feature,
1063 the program interruption transaction diagnostic block (TDB) is now
1064 represented as a number of additional "registers" in GDB.
1066 * New remote packets
1070 The vCont packet supports a new 'r' action, that tells the remote
1071 stub to step through an address range itself, without GDB
1072 involvemement at each single-step.
1074 qXfer:libraries-svr4:read's annex
1075 The previously unused annex of the qXfer:libraries-svr4:read packet
1076 is now used to support passing an argument list. The remote stub
1077 reports support for this argument list to GDB's qSupported query.
1078 The defined arguments are "start" and "prev", used to reduce work
1079 necessary for library list updating, resulting in significant
1082 * New features in the GDB remote stub, GDBserver
1084 ** GDBserver now supports target-assisted range stepping. Currently
1085 enabled on x86/x86_64 GNU/Linux targets.
1087 ** GDBserver now adds element 'tvar' in the XML in the reply to
1088 'qXfer:traceframe-info:read'. It has the id of the collected
1089 trace state variables.
1091 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1094 * New 'z' formatter for printing and examining memory, this displays the
1095 value as hexadecimal zero padded on the left to the size of the type.
1097 * GDB can now use Windows x64 unwinding data.
1099 * The "set remotebaud" command has been replaced by "set serial baud".
1100 Similarly, "show remotebaud" has been replaced by "show serial baud".
1101 The "set remotebaud" and "show remotebaud" commands are still available
1102 to provide backward compatibility with older versions of GDB.
1104 *** Changes in GDB 7.6
1106 * Target record has been renamed to record-full.
1107 Record/replay is now enabled with the "record full" command.
1108 This also affects settings that are associated with full record/replay
1109 that have been moved from "set/show record" to "set/show record full":
1111 set|show record full insn-number-max
1112 set|show record full stop-at-limit
1113 set|show record full memory-query
1115 * A new record target "record-btrace" has been added. The new target
1116 uses hardware support to record the control-flow of a process. It
1117 does not support replaying the execution, but it implements the
1118 below new commands for investigating the recorded execution log.
1119 This new recording method can be enabled using:
1123 The "record-btrace" target is only available on Intel Atom processors
1124 and requires a Linux kernel 2.6.32 or later.
1126 * Two new commands have been added for record/replay to give information
1127 about the recorded execution without having to replay the execution.
1128 The commands are only supported by "record btrace".
1130 record instruction-history prints the execution history at
1131 instruction granularity
1133 record function-call-history prints the execution history at
1134 function granularity
1136 * New native configurations
1138 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1139 FreeBSD/powerpc powerpc*-*-freebsd
1140 x86_64/Cygwin x86_64-*-cygwin*
1141 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1145 ARM AArch64 aarch64*-*-elf
1146 ARM AArch64 GNU/Linux aarch64*-*-linux
1147 Lynx 178 PowerPC powerpc-*-lynx*178
1148 x86_64/Cygwin x86_64-*-cygwin*
1149 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1151 * If the configured location of system.gdbinit file (as given by the
1152 --with-system-gdbinit option at configure time) is in the
1153 data-directory (as specified by --with-gdb-datadir at configure
1154 time) or in one of its subdirectories, then GDB will look for the
1155 system-wide init file in the directory specified by the
1156 --data-directory command-line option.
1158 * New command line options:
1160 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1161 other initialization files, unlike -nx which disables all of them.
1163 * Removed command line options
1165 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1168 * The 'ptype' and 'whatis' commands now accept an argument to control
1171 * 'info proc' now works on some core files.
1175 ** Vectors can be created with gdb.Type.vector.
1177 ** Python's atexit.register now works in GDB.
1179 ** Types can be pretty-printed via a Python API.
1181 ** Python 3 is now supported (in addition to Python 2.4 or later)
1183 ** New class gdb.Architecture exposes GDB's internal representation
1184 of architecture in the Python API.
1186 ** New method Frame.architecture returns the gdb.Architecture object
1187 corresponding to the frame's architecture.
1189 * New Python-based convenience functions:
1191 ** $_memeq(buf1, buf2, length)
1192 ** $_streq(str1, str2)
1194 ** $_regex(str, regex)
1196 * The 'cd' command now defaults to using '~' (the home directory) if not
1199 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1200 default for GCC since November 2000.
1202 * The command 'forward-search' can now be abbreviated as 'fo'.
1204 * The command 'info tracepoints' can now display 'installed on target'
1205 or 'not installed on target' for each non-pending location of tracepoint.
1207 * New configure options
1209 --enable-libmcheck/--disable-libmcheck
1210 By default, development versions are built with -lmcheck on hosts
1211 that support it, in order to help track memory corruption issues.
1212 Release versions, on the other hand, are built without -lmcheck
1213 by default. The --enable-libmcheck/--disable-libmcheck configure
1214 options allow the user to override that default.
1215 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1216 This configure option allows the user to build GDB with
1217 libbabeltrace using which GDB can read Common Trace Format data.
1219 * New commands (for set/show, see "New options" below)
1222 Catch signals. This is similar to "handle", but allows commands and
1223 conditions to be attached.
1226 List the BFDs known to GDB.
1228 python-interactive [command]
1230 Start a Python interactive prompt, or evaluate the optional command
1231 and print the result of expressions.
1234 "py" is a new alias for "python".
1236 enable type-printer [name]...
1237 disable type-printer [name]...
1238 Enable or disable type printers.
1242 ** For the Renesas Super-H architecture, the "regs" command has been removed
1243 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1248 set print type methods (on|off)
1249 show print type methods
1250 Control whether method declarations are displayed by "ptype".
1251 The default is to show them.
1253 set print type typedefs (on|off)
1254 show print type typedefs
1255 Control whether typedef definitions are displayed by "ptype".
1256 The default is to show them.
1258 set filename-display basename|relative|absolute
1259 show filename-display
1260 Control the way in which filenames is displayed.
1261 The default is "relative", which preserves previous behavior.
1263 set trace-buffer-size
1264 show trace-buffer-size
1265 Request target to change the size of trace buffer.
1267 set remote trace-buffer-size-packet auto|on|off
1268 show remote trace-buffer-size-packet
1269 Control the use of the remote protocol `QTBuffer:size' packet.
1273 Control display of debugging messages related to ARM AArch64.
1276 set debug coff-pe-read
1277 show debug coff-pe-read
1278 Control display of debugging messages related to reading of COFF/PE
1283 Control display of debugging messages related to Mach-O symbols
1286 set debug notification
1287 show debug notification
1288 Control display of debugging info for async remote notification.
1292 ** Command parameter changes are now notified using new async record
1293 "=cmd-param-changed".
1294 ** Trace frame changes caused by command "tfind" are now notified using
1295 new async record "=traceframe-changed".
1296 ** The creation, deletion and modification of trace state variables
1297 are now notified using new async records "=tsv-created",
1298 "=tsv-deleted" and "=tsv-modified".
1299 ** The start and stop of process record are now notified using new
1300 async record "=record-started" and "=record-stopped".
1301 ** Memory changes are now notified using new async record
1303 ** The data-disassemble command response will include a "fullname" field
1304 containing the absolute file name when source has been requested.
1305 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1306 command, to allow pattern filling of memory areas.
1307 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1308 library load/unload events.
1309 ** The response to breakpoint commands and breakpoint async records
1310 includes an "installed" field containing a boolean state about each
1311 non-pending tracepoint location is whether installed on target or not.
1312 ** Output of the "-trace-status" command includes a "trace-file" field
1313 containing the name of the trace file being examined. This field is
1314 optional, and only present when examining a trace file.
1315 ** The "fullname" field is now always present along with the "file" field,
1316 even if the file cannot be found by GDB.
1318 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1319 You must have the LZMA library available when configuring GDB for this
1320 feature to be enabled. For more information, see:
1321 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1323 * New remote packets
1326 Set the size of trace buffer. The remote stub reports support for this
1327 packet to gdb's qSupported query.
1330 Enable Branch Trace Store (BTS)-based branch tracing for the current
1331 thread. The remote stub reports support for this packet to gdb's
1335 Disable branch tracing for the current thread. The remote stub reports
1336 support for this packet to gdb's qSupported query.
1339 Read the traced branches for the current thread. The remote stub
1340 reports support for this packet to gdb's qSupported query.
1342 *** Changes in GDB 7.5
1344 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1345 for more x32 ABI info.
1347 * GDB now supports access to MIPS DSP registers on Linux targets.
1349 * GDB now supports debugging microMIPS binaries.
1351 * The "info os" command on GNU/Linux can now display information on
1352 several new classes of objects managed by the operating system:
1353 "info os procgroups" lists process groups
1354 "info os files" lists file descriptors
1355 "info os sockets" lists internet-domain sockets
1356 "info os shm" lists shared-memory regions
1357 "info os semaphores" lists semaphores
1358 "info os msg" lists message queues
1359 "info os modules" lists loaded kernel modules
1361 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1362 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1363 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1364 options and inspect the probe arguments using the new $_probe_arg family
1365 of convenience variables. You can obtain more information about SystemTap
1366 in <http://sourceware.org/systemtap/>.
1368 * GDB now supports reversible debugging on ARM, it allows you to
1369 debug basic ARM and THUMB instructions, and provides
1370 record/replay support.
1372 * The option "symbol-reloading" has been deleted as it is no longer used.
1376 ** GDB commands implemented in Python can now be put in command class
1379 ** The "maint set python print-stack on|off" is now deleted.
1381 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1382 apply "flag enum"-style pretty-printing to any enum.
1384 ** gdb.lookup_symbol can now work when there is no current frame.
1386 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1387 the source at which the symbol was defined.
1389 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1390 method 'value'. The former indicates whether the symbol needs a
1391 frame in order to compute its value, and the latter computes the
1394 ** A new method 'referenced_value' on gdb.Value objects which can
1395 dereference pointer as well as C++ reference values.
1397 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1398 which return the global and static blocks (as gdb.Block objects),
1399 of the underlying symbol table, respectively.
1401 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1402 object associated with a PC value.
1404 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1405 of the address range occupied by code for the current source line.
1407 * Go language support.
1408 GDB now supports debugging programs written in the Go programming
1411 * GDBserver now supports stdio connections.
1412 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1414 * The binary "gdbtui" can no longer be built or installed.
1415 Use "gdb -tui" instead.
1417 * GDB will now print "flag" enums specially. A flag enum is one where
1418 all the enumerator values have no bits in common when pairwise
1419 "and"ed. When printing a value whose type is a flag enum, GDB will
1420 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1421 (gdb) print (enum E) 3
1424 * The filename part of a linespec will now match trailing components
1425 of a source file name. For example, "break gcc/expr.c:1000" will
1426 now set a breakpoint in build/gcc/expr.c, but not
1427 build/libcpp/expr.c.
1429 * The "info proc" and "generate-core-file" commands will now also
1430 work on remote targets connected to GDBserver on Linux.
1432 * The command "info catch" has been removed. It has been disabled
1433 since December 2007.
1435 * The "catch exception" and "catch assert" commands now accept
1436 a condition at the end of the command, much like the "break"
1437 command does. For instance:
1439 (gdb) catch exception Constraint_Error if Barrier = True
1441 Previously, it was possible to add a condition to such catchpoints,
1442 but it had to be done as a second step, after the catchpoint had been
1443 created, using the "condition" command.
1445 * The "info static-tracepoint-marker" command will now also work on
1446 native Linux targets with in-process agent.
1448 * GDB can now set breakpoints on inlined functions.
1450 * The .gdb_index section has been updated to include symbols for
1451 inlined functions. GDB will ignore older .gdb_index sections by
1452 default, which could cause symbol files to be loaded more slowly
1453 until their .gdb_index sections can be recreated. The new command
1454 "set use-deprecated-index-sections on" will cause GDB to use any older
1455 .gdb_index sections it finds. This will restore performance, but the
1456 ability to set breakpoints on inlined functions will be lost in symbol
1457 files with older .gdb_index sections.
1459 The .gdb_index section has also been updated to record more information
1460 about each symbol. This speeds up the "info variables", "info functions"
1461 and "info types" commands when used with programs having the .gdb_index
1462 section, as well as speeding up debugging with shared libraries using
1463 the .gdb_index section.
1465 * Ada support for GDB/MI Variable Objects has been added.
1467 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1472 ** New command -info-os is the MI equivalent of "info os".
1474 ** Output logs ("set logging" and related) now include MI output.
1478 ** "set use-deprecated-index-sections on|off"
1479 "show use-deprecated-index-sections on|off"
1480 Controls the use of deprecated .gdb_index sections.
1482 ** "catch load" and "catch unload" can be used to stop when a shared
1483 library is loaded or unloaded, respectively.
1485 ** "enable count" can be used to auto-disable a breakpoint after
1488 ** "info vtbl" can be used to show the virtual method tables for
1489 C++ and Java objects.
1491 ** "explore" and its sub commands "explore value" and "explore type"
1492 can be used to recursively explore values and types of
1493 expressions. These commands are available only if GDB is
1494 configured with '--with-python'.
1496 ** "info auto-load" shows status of all kinds of auto-loaded files,
1497 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1498 sequences of commands files, "info auto-load python-scripts"
1499 shows status of auto-loading Python script files,
1500 "info auto-load local-gdbinit" shows status of loading init file
1501 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1502 status of inferior specific thread debugging shared library loading.
1504 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1505 and "show auto-load-scripts" commands have been deprecated, use their
1506 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1507 and "show auto-load python-scripts" counterparts instead.
1509 ** "dprintf location,format,args..." creates a dynamic printf, which
1510 is basically a breakpoint that does a printf and immediately
1511 resumes your program's execution, so it is like a printf that you
1512 can insert dynamically at runtime instead of at compiletime.
1514 ** "set print symbol"
1516 Controls whether GDB attempts to display the symbol, if any,
1517 corresponding to addresses it prints. This defaults to "on", but
1518 you can set it to "off" to restore GDB's previous behavior.
1520 * Deprecated commands
1522 ** For the Renesas Super-H architecture, the "regs" command has been
1523 deprecated, and "info all-registers" should be used instead.
1527 Renesas RL78 rl78-*-elf
1528 HP OpenVMS ia64 ia64-hp-openvms*
1530 * GDBserver supports evaluation of breakpoint conditions. When
1531 support is advertised by GDBserver, GDB may be told to send the
1532 breakpoint conditions in bytecode form to GDBserver. GDBserver
1533 will only report the breakpoint trigger to GDB when its condition
1538 set mips compression
1539 show mips compression
1540 Select the compressed ISA encoding used in functions that have no symbol
1541 information available. The encoding can be set to either of:
1544 and is updated automatically from ELF file flags if available.
1546 set breakpoint condition-evaluation
1547 show breakpoint condition-evaluation
1548 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1549 GDBserver ("target"). Default option "auto" chooses the most efficient
1551 This option can improve debugger efficiency depending on the speed of the
1555 Disable auto-loading globally.
1558 Show auto-loading setting of all kinds of auto-loaded files.
1560 set auto-load gdb-scripts on|off
1561 show auto-load gdb-scripts
1562 Control auto-loading of GDB canned sequences of commands files.
1564 set auto-load python-scripts on|off
1565 show auto-load python-scripts
1566 Control auto-loading of Python script files.
1568 set auto-load local-gdbinit on|off
1569 show auto-load local-gdbinit
1570 Control loading of init file (.gdbinit) from current directory.
1572 set auto-load libthread-db on|off
1573 show auto-load libthread-db
1574 Control auto-loading of inferior specific thread debugging shared library.
1576 set auto-load scripts-directory <dir1>[:<dir2>...]
1577 show auto-load scripts-directory
1578 Set a list of directories from which to load auto-loaded scripts.
1579 Automatically loaded Python scripts and GDB scripts are located in one
1580 of the directories listed by this option.
1581 The delimiter (':' above) may differ according to the host platform.
1583 set auto-load safe-path <dir1>[:<dir2>...]
1584 show auto-load safe-path
1585 Set a list of directories from which it is safe to auto-load files.
1586 The delimiter (':' above) may differ according to the host platform.
1588 set debug auto-load on|off
1589 show debug auto-load
1590 Control display of debugging info for auto-loading the files above.
1592 set dprintf-style gdb|call|agent
1594 Control the way in which a dynamic printf is performed; "gdb"
1595 requests a GDB printf command, while "call" causes dprintf to call a
1596 function in the inferior. "agent" requests that the target agent
1597 (such as GDBserver) do the printing.
1599 set dprintf-function <expr>
1600 show dprintf-function
1601 set dprintf-channel <expr>
1602 show dprintf-channel
1603 Set the function and optional first argument to the call when using
1604 the "call" style of dynamic printf.
1606 set disconnected-dprintf on|off
1607 show disconnected-dprintf
1608 Control whether agent-style dynamic printfs continue to be in effect
1609 after GDB disconnects.
1611 * New configure options
1613 --with-auto-load-dir
1614 Configure default value for the 'set auto-load scripts-directory'
1615 setting above. It defaults to '$debugdir:$datadir/auto-load',
1616 $debugdir representing global debugging info directories (available
1617 via 'show debug-file-directory') and $datadir representing GDB's data
1618 directory (available via 'show data-directory').
1620 --with-auto-load-safe-path
1621 Configure default value for the 'set auto-load safe-path' setting
1622 above. It defaults to the --with-auto-load-dir setting.
1624 --without-auto-load-safe-path
1625 Set 'set auto-load safe-path' to '/', effectively disabling this
1628 * New remote packets
1630 z0/z1 conditional breakpoints extension
1632 The z0/z1 breakpoint insertion packets have been extended to carry
1633 a list of conditional expressions over to the remote stub depending on the
1634 condition evaluation mode. The use of this extension can be controlled
1635 via the "set remote conditional-breakpoints-packet" command.
1639 Specify the signals which the remote stub may pass to the debugged
1640 program without GDB involvement.
1642 * New command line options
1644 --init-command=FILE, -ix Like --command, -x but execute it
1645 before loading inferior.
1646 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1647 execute it before loading inferior.
1649 *** Changes in GDB 7.4
1651 * GDB now handles ambiguous linespecs more consistently; the existing
1652 FILE:LINE support has been expanded to other types of linespecs. A
1653 breakpoint will now be set on all matching locations in all
1654 inferiors, and locations will be added or removed according to
1657 * GDB now allows you to skip uninteresting functions and files when
1658 stepping with the "skip function" and "skip file" commands.
1660 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1661 and "show remote hardware-watchpoint-length-limit". These allows to
1662 set or show the maximum length limit (in bytes) of a remote
1663 target hardware watchpoint.
1665 This allows e.g. to use "unlimited" hardware watchpoints with the
1666 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1667 watchpoints are slower than real hardware watchpoints but are
1668 significantly faster than gdb software watchpoints.
1672 ** The register_pretty_printer function in module gdb.printing now takes
1673 an optional `replace' argument. If True, the new printer replaces any
1676 ** The "maint set python print-stack on|off" command has been
1677 deprecated and will be deleted in GDB 7.5.
1678 A new command: "set python print-stack none|full|message" has
1679 replaced it. Additionally, the default for "print-stack" is
1680 now "message", which just prints the error message without
1683 ** A prompt substitution hook (prompt_hook) is now available to the
1686 ** A new Python module, gdb.prompt has been added to the GDB Python
1687 modules library. This module provides functionality for
1688 escape sequences in prompts (used by set/show
1689 extended-prompt). These escape sequences are replaced by their
1690 corresponding value.
1692 ** Python commands and convenience-functions located in
1693 'data-directory'/python/gdb/command and
1694 'data-directory'/python/gdb/function are now automatically loaded
1697 ** Blocks now provide four new attributes. global_block and
1698 static_block will return the global and static blocks
1699 respectively. is_static and is_global are boolean attributes
1700 that indicate if the block is one of those two types.
1702 ** Symbols now provide the "type" attribute, the type of the symbol.
1704 ** The "gdb.breakpoint" function has been deprecated in favor of
1707 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1708 of a function. This class is based on the "finish" command
1709 available in the CLI.
1711 ** Type objects for struct and union types now allow access to
1712 the fields using standard Python dictionary (mapping) methods.
1713 For example, "some_type['myfield']" now works, as does
1714 "some_type.items()".
1716 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1719 ** A new function, "deep_items" has been added to the gdb.types
1720 module in the GDB Python modules library. This function returns
1721 an iterator over the fields of a struct or union type. Unlike
1722 the standard Python "iteritems" method, it will recursively traverse
1723 any anonymous fields.
1727 ** "*stopped" events can report several new "reason"s, such as
1730 ** Breakpoint changes are now notified using new async records, like
1731 "=breakpoint-modified".
1733 ** New command -ada-task-info.
1735 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1736 $sdir specifies the default system locations of shared libraries.
1737 $pdir specifies the directory where the libpthread used by the application
1740 GDB no longer looks in $sdir and $pdir after it has searched the directories
1741 mentioned in libthread-db-search-path. If you want to search those
1742 directories, they must be specified in libthread-db-search-path.
1743 The default value of libthread-db-search-path on GNU/Linux and Solaris
1744 systems is now "$sdir:$pdir".
1746 $pdir is not supported by gdbserver, it is currently ignored.
1747 $sdir is supported by gdbserver.
1749 * New configure option --with-iconv-bin.
1750 When using the internationalization support like the one in the GNU C
1751 library, GDB will invoke the "iconv" program to get a list of supported
1752 character sets. If this program lives in a non-standard location, one can
1753 use this option to specify where to find it.
1755 * When natively debugging programs on PowerPC BookE processors running
1756 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1757 watchpoints, which specify a mask in addition to an address to watch.
1758 The mask specifies that some bits of an address (the bits which are
1759 reset in the mask) should be ignored when matching the address accessed
1760 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1761 section in the user manual for more details.
1763 * The new option --once causes GDBserver to stop listening for connections once
1764 the first connection is made. The listening port used by GDBserver will
1765 become available after that.
1767 * New commands "info macros" and "alias" have been added.
1769 * New function parameters suffix @entry specifies value of function parameter
1770 at the time the function got called. Entry values are available only since
1776 "!" is now an alias of the "shell" command.
1777 Note that no space is needed between "!" and SHELL COMMAND.
1781 watch EXPRESSION mask MASK_VALUE
1782 The watch command now supports the mask argument which allows creation
1783 of masked watchpoints, if the current architecture supports this feature.
1785 info auto-load-scripts [REGEXP]
1786 This command was formerly named "maintenance print section-scripts".
1787 It is now generally useful and is no longer a maintenance-only command.
1789 info macro [-all] [--] MACRO
1790 The info macro command has new options `-all' and `--'. The first for
1791 printing all definitions of a macro. The second for explicitly specifying
1792 the end of arguments and the beginning of the macro name in case the macro
1793 name starts with a hyphen.
1795 collect[/s] EXPRESSIONS
1796 The tracepoint collect command now takes an optional modifier "/s"
1797 that directs it to dereference pointer-to-character types and
1798 collect the bytes of memory up to a zero byte. The behavior is
1799 similar to what you see when you use the regular print command on a
1800 string. An optional integer following the "/s" sets a bound on the
1801 number of bytes that will be collected.
1804 The trace start command now interprets any supplied arguments as a
1805 note to be recorded with the trace run, with an effect similar to
1806 setting the variable trace-notes.
1809 The trace stop command now interprets any arguments as a note to be
1810 mentioned along with the tstatus report that the trace was stopped
1811 with a command. The effect is similar to setting the variable
1814 * Tracepoints can now be enabled and disabled at any time after a trace
1815 experiment has been started using the standard "enable" and "disable"
1816 commands. It is now possible to start a trace experiment with no enabled
1817 tracepoints; GDB will display a warning, but will allow the experiment to
1818 begin, assuming that tracepoints will be enabled as needed while the trace
1821 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1822 locations with 4-byte instructions, when they were previously
1823 limited to locations with instructions of 5 bytes or longer.
1827 set debug dwarf2-read
1828 show debug dwarf2-read
1829 Turns on or off display of debugging messages related to reading
1830 DWARF debug info. The default is off.
1832 set debug symtab-create
1833 show debug symtab-create
1834 Turns on or off display of debugging messages related to symbol table
1835 creation. The default is off.
1838 show extended-prompt
1839 Set the GDB prompt, and allow escape sequences to be inserted to
1840 display miscellaneous information (see 'help set extended-prompt'
1841 for the list of sequences). This prompt (and any information
1842 accessed through the escape sequences) is updated every time the
1843 prompt is displayed.
1845 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1846 show print entry-values
1847 Set printing of frame argument values at function entry. In some cases
1848 GDB can determine the value of function argument which was passed by the
1849 function caller, even if the value was modified inside the called function.
1851 set debug entry-values
1852 show debug entry-values
1853 Control display of debugging info for determining frame argument values at
1854 function entry and virtual tail call frames.
1856 set basenames-may-differ
1857 show basenames-may-differ
1858 Set whether a source file may have multiple base names.
1859 (A "base name" is the name of a file with the directory part removed.
1860 Example: The base name of "/home/user/hello.c" is "hello.c".)
1861 If set, GDB will canonicalize file names (e.g., expand symlinks)
1862 before comparing them. Canonicalization is an expensive operation,
1863 but it allows the same file be known by more than one base name.
1864 If not set (the default), all source files are assumed to have just
1865 one base name, and gdb will do file name comparisons more efficiently.
1871 Set a user name and notes for the current and any future trace runs.
1872 This is useful for long-running and/or disconnected traces, to
1873 inform others (or yourself) as to who is running the trace, supply
1874 contact information, or otherwise explain what is going on.
1876 set trace-stop-notes
1877 show trace-stop-notes
1878 Set a note attached to the trace run, that is displayed when the
1879 trace has been stopped by a tstop command. This is useful for
1880 instance as an explanation, if you are stopping a trace run that was
1881 started by someone else.
1883 * New remote packets
1887 Dynamically enable a tracepoint in a started trace experiment.
1891 Dynamically disable a tracepoint in a started trace experiment.
1895 Set the user and notes of the trace run.
1899 Query the current status of a tracepoint.
1903 Query the minimum length of instruction at which a fast tracepoint may
1906 * Dcache size (number of lines) and line-size are now runtime-configurable
1907 via "set dcache line" and "set dcache line-size" commands.
1911 Texas Instruments TMS320C6x tic6x-*-*
1915 Renesas RL78 rl78-*-elf
1917 *** Changes in GDB 7.3.1
1919 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1921 *** Changes in GDB 7.3
1923 * GDB has a new command: "thread find [REGEXP]".
1924 It finds the thread id whose name, target id, or thread extra info
1925 matches the given regular expression.
1927 * The "catch syscall" command now works on mips*-linux* targets.
1929 * The -data-disassemble MI command now supports modes 2 and 3 for
1930 dumping the instruction opcodes.
1932 * New command line options
1934 -data-directory DIR Specify DIR as the "data-directory".
1935 This is mostly for testing purposes.
1937 * The "maint set python auto-load on|off" command has been renamed to
1938 "set auto-load-scripts on|off".
1940 * GDB has a new command: "set directories".
1941 It is like the "dir" command except that it replaces the
1942 source path list instead of augmenting it.
1944 * GDB now understands thread names.
1946 On GNU/Linux, "info threads" will display the thread name as set by
1947 prctl or pthread_setname_np.
1949 There is also a new command, "thread name", which can be used to
1950 assign a name internally for GDB to display.
1953 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1954 has been integrated into GDB.
1958 ** The function gdb.Write now accepts an optional keyword 'stream'.
1959 This keyword, when provided, will direct the output to either
1960 stdout, stderr, or GDB's logging output.
1962 ** Parameters can now be be sub-classed in Python, and in particular
1963 you may implement the get_set_doc and get_show_doc functions.
1964 This improves how Parameter set/show documentation is processed
1965 and allows for more dynamic content.
1967 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1968 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1969 have an is_valid method.
1971 ** Breakpoints can now be sub-classed in Python, and in particular
1972 you may implement a 'stop' function that is executed each time
1973 the inferior reaches that breakpoint.
1975 ** New function gdb.lookup_global_symbol looks up a global symbol.
1977 ** GDB values in Python are now callable if the value represents a
1978 function. For example, if 'some_value' represents a function that
1979 takes two integer parameters and returns a value, you can call
1980 that function like so:
1982 result = some_value (10,20)
1984 ** Module gdb.types has been added.
1985 It contains a collection of utilities for working with gdb.Types objects:
1986 get_basic_type, has_field, make_enum_dict.
1988 ** Module gdb.printing has been added.
1989 It contains utilities for writing and registering pretty-printers.
1990 New classes: PrettyPrinter, SubPrettyPrinter,
1991 RegexpCollectionPrettyPrinter.
1992 New function: register_pretty_printer.
1994 ** New commands "info pretty-printers", "enable pretty-printer" and
1995 "disable pretty-printer" have been added.
1997 ** gdb.parameter("directories") is now available.
1999 ** New function gdb.newest_frame returns the newest frame in the
2002 ** The gdb.InferiorThread class has a new "name" attribute. This
2003 holds the thread's name.
2005 ** Python Support for Inferior events.
2006 Python scripts can add observers to be notified of events
2007 occurring in the process being debugged.
2008 The following events are currently supported:
2009 - gdb.events.cont Continue event.
2010 - gdb.events.exited Inferior exited event.
2011 - gdb.events.stop Signal received, and Breakpoint hit events.
2015 ** GDB now puts template parameters in scope when debugging in an
2016 instantiation. For example, if you have:
2018 template<int X> int func (void) { return X; }
2020 then if you step into func<5>, "print X" will show "5". This
2021 feature requires proper debuginfo support from the compiler; it
2022 was added to GCC 4.5.
2024 ** The motion commands "next", "finish", "until", and "advance" now
2025 work better when exceptions are thrown. In particular, GDB will
2026 no longer lose control of the inferior; instead, the GDB will
2027 stop the inferior at the point at which the exception is caught.
2028 This functionality requires a change in the exception handling
2029 code that was introduced in GCC 4.5.
2031 * GDB now follows GCC's rules on accessing volatile objects when
2032 reading or writing target state during expression evaluation.
2033 One notable difference to prior behavior is that "print x = 0"
2034 no longer generates a read of x; the value of the assignment is
2035 now always taken directly from the value being assigned.
2037 * GDB now has some support for using labels in the program's source in
2038 linespecs. For instance, you can use "advance label" to continue
2039 execution to a label.
2041 * GDB now has support for reading and writing a new .gdb_index
2042 section. This section holds a fast index of DWARF debugging
2043 information and can be used to greatly speed up GDB startup and
2044 operation. See the documentation for `save gdb-index' for details.
2046 * The "watch" command now accepts an optional "-location" argument.
2047 When used, this causes GDB to watch the memory referred to by the
2048 expression. Such a watchpoint is never deleted due to it going out
2051 * GDB now supports thread debugging of core dumps on GNU/Linux.
2053 GDB now activates thread debugging using the libthread_db library
2054 when debugging GNU/Linux core dumps, similarly to when debugging
2055 live processes. As a result, when debugging a core dump file, GDB
2056 is now able to display pthread_t ids of threads. For example, "info
2057 threads" shows the same output as when debugging the process when it
2058 was live. In earlier releases, you'd see something like this:
2061 * 1 LWP 6780 main () at main.c:10
2063 While now you see this:
2066 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2068 It is also now possible to inspect TLS variables when debugging core
2071 When debugging a core dump generated on a machine other than the one
2072 used to run GDB, you may need to point GDB at the correct
2073 libthread_db library with the "set libthread-db-search-path"
2074 command. See the user manual for more details on this command.
2076 * When natively debugging programs on PowerPC BookE processors running
2077 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2078 which stop execution of the inferior whenever it executes an instruction
2079 at any address within the specified range. See the "PowerPC Embedded"
2080 section in the user manual for more details.
2082 * New features in the GDB remote stub, GDBserver
2084 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2085 and i686 LynxOS (version 5.x).
2087 ** GDBserver is now supported on Blackfin Linux.
2089 * New native configurations
2091 ia64 HP-UX ia64-*-hpux*
2095 Analog Devices, Inc. Blackfin Processor bfin-*
2097 * Ada task switching is now supported on sparc-elf targets when
2098 debugging a program using the Ravenscar Profile. For more information,
2099 see the "Tasking Support when using the Ravenscar Profile" section
2100 in the GDB user manual.
2102 * Guile support was removed.
2104 * New features in the GNU simulator
2106 ** The --map-info flag lists all known core mappings.
2108 ** CFI flashes may be simulated via the "cfi" device.
2110 *** Changes in GDB 7.2
2112 * Shared library support for remote targets by default
2114 When GDB is configured for a generic, non-OS specific target, like
2115 for example, --target=arm-eabi or one of the many *-*-elf targets,
2116 GDB now queries remote stubs for loaded shared libraries using the
2117 `qXfer:libraries:read' packet. Previously, shared library support
2118 was always disabled for such configurations.
2122 ** Argument Dependent Lookup (ADL)
2124 In C++ ADL lookup directs function search to the namespaces of its
2125 arguments even if the namespace has not been imported.
2135 Here the compiler will search for `foo' in the namespace of 'b'
2136 and find A::foo. GDB now supports this. This construct is commonly
2137 used in the Standard Template Library for operators.
2139 ** Improved User Defined Operator Support
2141 In addition to member operators, GDB now supports lookup of operators
2142 defined in a namespace and imported with a `using' directive, operators
2143 defined in the global scope, operators imported implicitly from an
2144 anonymous namespace, and the ADL operators mentioned in the previous
2146 GDB now also supports proper overload resolution for all the previously
2147 mentioned flavors of operators.
2149 ** static const class members
2151 Printing of static const class members that are initialized in the
2152 class definition has been fixed.
2154 * Windows Thread Information Block access.
2156 On Windows targets, GDB now supports displaying the Windows Thread
2157 Information Block (TIB) structure. This structure is visible either
2158 by using the new command `info w32 thread-information-block' or, by
2159 dereferencing the new convenience variable named `$_tlb', a
2160 thread-specific pointer to the TIB. This feature is also supported
2161 when remote debugging using GDBserver.
2163 * Static tracepoints
2165 Static tracepoints are calls in the user program into a tracing
2166 library. One such library is a port of the LTTng kernel tracer to
2167 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2168 When debugging with GDBserver, GDB now supports combining the GDB
2169 tracepoint machinery with such libraries. For example: the user can
2170 use GDB to probe a static tracepoint marker (a call from the user
2171 program into the tracing library) with the new "strace" command (see
2172 "New commands" below). This creates a "static tracepoint" in the
2173 breakpoint list, that can be manipulated with the same feature set
2174 as fast and regular tracepoints. E.g., collect registers, local and
2175 global variables, collect trace state variables, and define
2176 tracepoint conditions. In addition, the user can collect extra
2177 static tracepoint marker specific data, by collecting the new
2178 $_sdata internal variable. When analyzing the trace buffer, you can
2179 inspect $_sdata like any other variable available to GDB. For more
2180 information, see the "Tracepoints" chapter in GDB user manual. New
2181 remote packets have been defined to support static tracepoints, see
2182 the "New remote packets" section below.
2184 * Better reconstruction of tracepoints after disconnected tracing
2186 GDB will attempt to download the original source form of tracepoint
2187 definitions when starting a trace run, and then will upload these
2188 upon reconnection to the target, resulting in a more accurate
2189 reconstruction of the tracepoints that are in use on the target.
2193 You can now exercise direct control over the ways that GDB can
2194 affect your program. For instance, you can disallow the setting of
2195 breakpoints, so that the program can run continuously (assuming
2196 non-stop mode). In addition, the "observer" variable is available
2197 to switch all of the different controls; in observer mode, GDB
2198 cannot affect the target's behavior at all, which is useful for
2199 tasks like diagnosing live systems in the field.
2201 * The new convenience variable $_thread holds the number of the
2204 * New remote packets
2208 Return the address of the Windows Thread Information Block of a given thread.
2212 In response to several of the tracepoint packets, the target may now
2213 also respond with a number of intermediate `qRelocInsn' request
2214 packets before the final result packet, to have GDB handle
2215 relocating an instruction to execute at a different address. This
2216 is particularly useful for stubs that support fast tracepoints. GDB
2217 reports support for this feature in the qSupported packet.
2221 List static tracepoint markers in the target program.
2225 List static tracepoint markers at a given address in the target
2228 qXfer:statictrace:read
2230 Read the static trace data collected (by a `collect $_sdata'
2231 tracepoint action). The remote stub reports support for this packet
2232 to gdb's qSupported query.
2236 Send the current settings of GDB's permission flags.
2240 Send part of the source (textual) form of a tracepoint definition,
2241 which includes location, conditional, and action list.
2243 * The source command now accepts a -s option to force searching for the
2244 script in the source search path even if the script name specifies
2247 * New features in the GDB remote stub, GDBserver
2249 - GDBserver now support tracepoints (including fast tracepoints, and
2250 static tracepoints). The feature is currently supported by the
2251 i386-linux and amd64-linux builds. See the "Tracepoints support
2252 in gdbserver" section in the manual for more information.
2254 GDBserver JIT compiles the tracepoint's conditional agent
2255 expression bytecode into native code whenever possible for low
2256 overhead dynamic tracepoints conditionals. For such tracepoints,
2257 an expression that examines program state is evaluated when the
2258 tracepoint is reached, in order to determine whether to capture
2259 trace data. If the condition is simple and false, processing the
2260 tracepoint finishes very quickly and no data is gathered.
2262 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2263 for static tracepoints support.
2265 - GDBserver now supports x86_64 Windows 64-bit debugging.
2267 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2268 it understands register description.
2270 * The --batch flag now disables pagination and queries.
2272 * X86 general purpose registers
2274 GDB now supports reading/writing byte, word and double-word x86
2275 general purpose registers directly. This means you can use, say,
2276 $ah or $ax to refer, respectively, to the byte register AH and
2277 16-bit word register AX that are actually portions of the 32-bit
2278 register EAX or 64-bit register RAX.
2280 * The `commands' command now accepts a range of breakpoints to modify.
2281 A plain `commands' following a command that creates multiple
2282 breakpoints affects all the breakpoints set by that command. This
2283 applies to breakpoints set by `rbreak', and also applies when a
2284 single `break' command creates multiple breakpoints (e.g.,
2285 breakpoints on overloaded c++ functions).
2287 * The `rbreak' command now accepts a filename specification as part of
2288 its argument, limiting the functions selected by the regex to those
2289 in the specified file.
2291 * Support for remote debugging Windows and SymbianOS shared libraries
2292 from Unix hosts has been improved. Non Windows GDB builds now can
2293 understand target reported file names that follow MS-DOS based file
2294 system semantics, such as file names that include drive letters and
2295 use the backslash character as directory separator. This makes it
2296 possible to transparently use the "set sysroot" and "set
2297 solib-search-path" on Unix hosts to point as host copies of the
2298 target's shared libraries. See the new command "set
2299 target-file-system-kind" described below, and the "Commands to
2300 specify files" section in the user manual for more information.
2304 eval template, expressions...
2305 Convert the values of one or more expressions under the control
2306 of the string template to a command line, and call it.
2308 set target-file-system-kind unix|dos-based|auto
2309 show target-file-system-kind
2310 Set or show the assumed file system kind for target reported file
2313 save breakpoints <filename>
2314 Save all current breakpoint definitions to a file suitable for use
2315 in a later debugging session. To read the saved breakpoint
2316 definitions, use the `source' command.
2318 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2321 info static-tracepoint-markers
2322 Display information about static tracepoint markers in the target.
2324 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2325 Define a static tracepoint by probing a marker at the given
2326 function, line, address, or marker ID.
2330 Enable and disable observer mode.
2332 set may-write-registers on|off
2333 set may-write-memory on|off
2334 set may-insert-breakpoints on|off
2335 set may-insert-tracepoints on|off
2336 set may-insert-fast-tracepoints on|off
2337 set may-interrupt on|off
2338 Set individual permissions for GDB effects on the target. Note that
2339 some of these settings can have undesirable or surprising
2340 consequences, particularly when changed in the middle of a session.
2341 For instance, disabling the writing of memory can prevent
2342 breakpoints from being inserted, cause single-stepping to fail, or
2343 even crash your program, if you disable after breakpoints have been
2344 inserted. However, GDB should not crash.
2346 set record memory-query on|off
2347 show record memory-query
2348 Control whether to stop the inferior if memory changes caused
2349 by an instruction cannot be recorded.
2354 The disassemble command now supports "start,+length" form of two arguments.
2358 ** GDB now provides a new directory location, called the python directory,
2359 where Python scripts written for GDB can be installed. The location
2360 of that directory is <data-directory>/python, where <data-directory>
2361 is the GDB data directory. For more details, see section `Scripting
2362 GDB using Python' in the manual.
2364 ** The GDB Python API now has access to breakpoints, symbols, symbol
2365 tables, program spaces, inferiors, threads and frame's code blocks.
2366 Additionally, GDB Parameters can now be created from the API, and
2367 manipulated via set/show in the CLI.
2369 ** New functions gdb.target_charset, gdb.target_wide_charset,
2370 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2372 ** New exception gdb.GdbError.
2374 ** Pretty-printers are now also looked up in the current program space.
2376 ** Pretty-printers can now be individually enabled and disabled.
2378 ** GDB now looks for names of Python scripts to auto-load in a
2379 special section named `.debug_gdb_scripts', in addition to looking
2380 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2382 * Tracepoint actions were unified with breakpoint commands. In particular,
2383 there are no longer differences in "info break" output for breakpoints and
2384 tracepoints and the "commands" command can be used for both tracepoints and
2385 regular breakpoints.
2389 ARM Symbian arm*-*-symbianelf*
2391 * D language support.
2392 GDB now supports debugging programs written in the D programming
2395 * GDB now supports the extended ptrace interface for PowerPC which is
2396 available since Linux kernel version 2.6.34. This automatically enables
2397 any hardware breakpoints and additional hardware watchpoints available in
2398 the processor. The old ptrace interface exposes just one hardware
2399 watchpoint and no hardware breakpoints.
2401 * GDB is now able to use the Data Value Compare (DVC) register available on
2402 embedded PowerPC processors to implement in hardware simple watchpoint
2403 conditions of the form:
2405 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2407 This works in native GDB running on Linux kernels with the extended ptrace
2408 interface mentioned above.
2410 *** Changes in GDB 7.1
2414 ** Namespace Support
2416 GDB now supports importing of namespaces in C++. This enables the
2417 user to inspect variables from imported namespaces. Support for
2418 namepace aliasing has also been added. So, if a namespace is
2419 aliased in the current scope (e.g. namepace C=A; ) the user can
2420 print variables using the alias (e.g. (gdb) print C::x).
2424 All known bugs relating to the printing of virtual base class were
2425 fixed. It is now possible to call overloaded static methods using a
2430 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2431 and reinterpret_cast<> are now handled by the C++ expression parser.
2435 Xilinx MicroBlaze microblaze-*-*
2440 Xilinx MicroBlaze microblaze
2443 * Multi-program debugging.
2445 GDB now has support for multi-program (a.k.a. multi-executable or
2446 multi-exec) debugging. This allows for debugging multiple inferiors
2447 simultaneously each running a different program under the same GDB
2448 session. See "Debugging Multiple Inferiors and Programs" in the
2449 manual for more information. This implied some user visible changes
2450 in the multi-inferior support. For example, "info inferiors" now
2451 lists inferiors that are not running yet or that have exited
2452 already. See also "New commands" and "New options" below.
2454 * New tracing features
2456 GDB's tracepoint facility now includes several new features:
2458 ** Trace state variables
2460 GDB tracepoints now include support for trace state variables, which
2461 are variables managed by the target agent during a tracing
2462 experiment. They are useful for tracepoints that trigger each
2463 other, so for instance one tracepoint can count hits in a variable,
2464 and then a second tracepoint has a condition that is true when the
2465 count reaches a particular value. Trace state variables share the
2466 $-syntax of GDB convenience variables, and can appear in both
2467 tracepoint actions and condition expressions. Use the "tvariable"
2468 command to create, and "info tvariables" to view; see "Trace State
2469 Variables" in the manual for more detail.
2473 GDB now includes an option for defining fast tracepoints, which
2474 targets may implement more efficiently, such as by installing a jump
2475 into the target agent rather than a trap instruction. The resulting
2476 speedup can be by two orders of magnitude or more, although the
2477 tradeoff is that some program locations on some target architectures
2478 might not allow fast tracepoint installation, for instance if the
2479 instruction to be replaced is shorter than the jump. To request a
2480 fast tracepoint, use the "ftrace" command, with syntax identical to
2481 the regular trace command.
2483 ** Disconnected tracing
2485 It is now possible to detach GDB from the target while it is running
2486 a trace experiment, then reconnect later to see how the experiment
2487 is going. In addition, a new variable disconnected-tracing lets you
2488 tell the target agent whether to continue running a trace if the
2489 connection is lost unexpectedly.
2493 GDB now has the ability to save the trace buffer into a file, and
2494 then use that file as a target, similarly to you can do with
2495 corefiles. You can select trace frames, print data that was
2496 collected in them, and use tstatus to display the state of the
2497 tracing run at the moment that it was saved. To create a trace
2498 file, use "tsave <filename>", and to use it, do "target tfile
2501 ** Circular trace buffer
2503 You can ask the target agent to handle the trace buffer as a
2504 circular buffer, discarding the oldest trace frames to make room for
2505 newer ones, by setting circular-trace-buffer to on. This feature may
2506 not be available for all target agents.
2511 The disassemble command, when invoked with two arguments, now requires
2512 the arguments to be comma-separated.
2515 The info variables command now displays variable definitions. Files
2516 which only declare a variable are not shown.
2519 The source command is now capable of sourcing Python scripts.
2520 This feature is dependent on the debugger being build with Python
2523 Related to this enhancement is also the introduction of a new command
2524 "set script-extension" (see below).
2526 * New commands (for set/show, see "New options" below)
2528 record save [<FILENAME>]
2529 Save a file (in core file format) containing the process record
2530 execution log for replay debugging at a later time.
2532 record restore <FILENAME>
2533 Restore the process record execution log that was saved at an
2534 earlier time, for replay debugging.
2536 add-inferior [-copies <N>] [-exec <FILENAME>]
2539 clone-inferior [-copies <N>] [ID]
2540 Make a new inferior ready to execute the same program another
2541 inferior has loaded.
2546 maint info program-spaces
2547 List the program spaces loaded into GDB.
2549 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2550 show remote interrupt-sequence
2551 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2552 as the sequence to the remote target in order to interrupt the execution.
2553 Ctrl-C is a default. Some system prefers BREAK which is high level of
2554 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2555 Magic SysRq g. It is BREAK signal and character 'g'.
2557 set remote interrupt-on-connect [on | off]
2558 show remote interrupt-on-connect
2559 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2560 remote target when gdb connects to it. This is needed when you debug
2563 set remotebreak [on | off]
2565 Deprecated. Use "set/show remote interrupt-sequence" instead.
2567 tvariable $NAME [ = EXP ]
2568 Create or modify a trace state variable.
2571 List trace state variables and their values.
2573 delete tvariable $NAME ...
2574 Delete one or more trace state variables.
2577 Evaluate the given expressions without collecting anything into the
2578 trace buffer. (Valid in tracepoint actions only.)
2580 ftrace FN / FILE:LINE / *ADDR
2581 Define a fast tracepoint at the given function, line, or address.
2583 * New expression syntax
2585 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2586 GDB now parses 0b101010 identically with 42.
2590 set follow-exec-mode new|same
2591 show follow-exec-mode
2592 Control whether GDB reuses the same inferior across an exec call or
2593 creates a new one. This is useful to be able to restart the old
2594 executable after the inferior having done an exec call.
2596 set default-collect EXPR, ...
2597 show default-collect
2598 Define a list of expressions to be collected at each tracepoint.
2599 This is a useful way to ensure essential items are not overlooked,
2600 such as registers or a critical global variable.
2602 set disconnected-tracing
2603 show disconnected-tracing
2604 If set to 1, the target is instructed to continue tracing if it
2605 loses its connection to GDB. If 0, the target is to stop tracing
2608 set circular-trace-buffer
2609 show circular-trace-buffer
2610 If set to on, the target is instructed to use a circular trace buffer
2611 and discard the oldest trace frames instead of stopping the trace due
2612 to a full trace buffer. If set to off, the trace stops when the buffer
2613 fills up. Some targets may not support this.
2615 set script-extension off|soft|strict
2616 show script-extension
2617 If set to "off", the debugger does not perform any script language
2618 recognition, and all sourced files are assumed to be GDB scripts.
2619 If set to "soft" (the default), files are sourced according to
2620 filename extension, falling back to GDB scripts if the first
2622 If set to "strict", files are sourced according to filename extension.
2624 set ada trust-PAD-over-XVS on|off
2625 show ada trust-PAD-over-XVS
2626 If off, activate a workaround against a bug in the debugging information
2627 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2628 the GCC sources for more information about the GNAT encoding and
2629 PAD types in particular). It is always safe to set this option to
2630 off, but this introduces a slight performance penalty. The default
2633 * Python API Improvements
2635 ** GDB provides the new class gdb.LazyString. This is useful in
2636 some pretty-printing cases. The new method gdb.Value.lazy_string
2637 provides a simple way to create objects of this type.
2639 ** The fields returned by gdb.Type.fields now have an
2640 `is_base_class' attribute.
2642 ** The new method gdb.Type.range returns the range of an array type.
2644 ** The new method gdb.parse_and_eval can be used to parse and
2645 evaluate an expression.
2647 * New remote packets
2650 Define a trace state variable.
2653 Get the current value of a trace state variable.
2656 Set desired tracing behavior upon disconnection.
2659 Set the trace buffer to be linear or circular.
2662 Get data about the tracepoints currently in use.
2666 Process record now works correctly with hardware watchpoints.
2668 Multiple bug fixes have been made to the mips-irix port, making it
2669 much more reliable. In particular:
2670 - Debugging threaded applications is now possible again. Previously,
2671 GDB would hang while starting the program, or while waiting for
2672 the program to stop at a breakpoint.
2673 - Attaching to a running process no longer hangs.
2674 - An error occurring while loading a core file has been fixed.
2675 - Changing the value of the PC register now works again. This fixes
2676 problems observed when using the "jump" command, or when calling
2677 a function from GDB, or even when assigning a new value to $pc.
2678 - With the "finish" and "return" commands, the return value for functions
2679 returning a small array is now correctly printed.
2680 - It is now possible to break on shared library code which gets executed
2681 during a shared library init phase (code executed while executing
2682 their .init section). Previously, the breakpoint would have no effect.
2683 - GDB is now able to backtrace through the signal handler for
2684 non-threaded programs.
2686 PIE (Position Independent Executable) programs debugging is now supported.
2687 This includes debugging execution of PIC (Position Independent Code) shared
2688 libraries although for that, it should be possible to run such libraries as an
2691 *** Changes in GDB 7.0
2693 * GDB now has an interface for JIT compilation. Applications that
2694 dynamically generate code can create symbol files in memory and register
2695 them with GDB. For users, the feature should work transparently, and
2696 for JIT developers, the interface is documented in the GDB manual in the
2697 "JIT Compilation Interface" chapter.
2699 * Tracepoints may now be conditional. The syntax is as for
2700 breakpoints; either an "if" clause appended to the "trace" command,
2701 or the "condition" command is available. GDB sends the condition to
2702 the target for evaluation using the same bytecode format as is used
2703 for tracepoint actions.
2705 * The disassemble command now supports: an optional /r modifier, print the
2706 raw instructions in hex as well as in symbolic form, and an optional /m
2707 modifier to print mixed source+assembly.
2709 * Process record and replay
2711 In a architecture environment that supports ``process record and
2712 replay'', ``process record and replay'' target can record a log of
2713 the process execution, and replay it with both forward and reverse
2716 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2717 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2718 set execution-direction {forward|reverse}, for targets that support
2721 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2722 feature is available with a native GDB running on kernel version
2725 * GDB now has support for multi-byte and wide character sets on the
2726 target. Strings whose character type is wchar_t, char16_t, or
2727 char32_t are now correctly printed. GDB supports wide- and unicode-
2728 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2729 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2730 `printf'. This feature requires iconv to work properly; if your
2731 system does not have a working iconv, GDB can use GNU libiconv. See
2732 the installation instructions for more information.
2734 * GDB now supports automatic retrieval of shared library files from
2735 remote targets. To use this feature, specify a system root that begins
2736 with the `remote:' prefix, either via the `set sysroot' command or via
2737 the `--with-sysroot' configure-time option.
2739 * "info sharedlibrary" now takes an optional regex of libraries to show,
2740 and it now reports if a shared library has no debugging information.
2742 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2743 now complete on file names.
2745 * When completing in expressions, gdb will attempt to limit
2746 completions to allowable structure or union fields, where appropriate.
2747 For instance, consider:
2749 # struct example { int f1; double f2; };
2750 # struct example variable;
2753 If the user types TAB at the end of this command line, the available
2754 completions will be "f1" and "f2".
2756 * Inlined functions are now supported. They show up in backtraces, and
2757 the "step", "next", and "finish" commands handle them automatically.
2759 * GDB now supports the token-splicing (##) and stringification (#)
2760 operators when expanding macros. It also supports variable-arity
2763 * GDB now supports inspecting extra signal information, exported by
2764 the new $_siginfo convenience variable. The feature is currently
2765 implemented on linux ARM, i386 and amd64.
2767 * GDB can now display the VFP floating point registers and NEON vector
2768 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2769 can provide these registers (requires Linux 2.6.30 or later). Remote
2770 and simulator targets may also provide them.
2772 * New remote packets
2775 Search memory for a sequence of bytes.
2778 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2779 operation over reliable transport links. Use of this packet is
2780 controlled by the `set remote noack-packet' command.
2783 Kill the process with the specified process ID. Use this in preference
2784 to `k' when multiprocess protocol extensions are supported.
2787 Obtains additional operating system information
2791 Read or write additional signal information.
2793 * Removed remote protocol undocumented extension
2795 An undocumented extension to the remote protocol's `S' stop reply
2796 packet that permited the stub to pass a process id was removed.
2797 Remote servers should use the `T' stop reply packet instead.
2799 * GDB now supports multiple function calling conventions according to the
2800 DWARF-2 DW_AT_calling_convention function attribute.
2802 * The SH target utilizes the aforementioned change to distinguish between gcc
2803 and Renesas calling convention. It also adds the new CLI commands
2804 `set/show sh calling-convention'.
2806 * GDB can now read compressed debug sections, as produced by GNU gold
2807 with the --compress-debug-sections=zlib flag.
2809 * 64-bit core files are now supported on AIX.
2811 * Thread switching is now supported on Tru64.
2813 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2814 which will be allocated using malloc later in program execution.
2816 * The qXfer:libraries:read remote procotol packet now allows passing a
2817 list of section offsets.
2819 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2820 conditions handling signals delivered during attach or thread creation
2821 have also been fixed.
2823 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2824 From the user's standpoint, all unqualified instances of True and False
2825 are treated as the standard definitions, regardless of context.
2827 * GDB now parses C++ symbol and type names more flexibly. For
2830 template<typename T> class C { };
2833 GDB will now correctly handle all of:
2835 ptype C<char const *>
2836 ptype C<char const*>
2837 ptype C<const char *>
2838 ptype C<const char*>
2840 * New features in the GDB remote stub, gdbserver
2842 - The "--wrapper" command-line argument tells gdbserver to use a
2843 wrapper program to launch programs for debugging.
2845 - On PowerPC and S/390 targets, it is now possible to use a single
2846 gdbserver executable to debug both 32-bit and 64-bit programs.
2847 (This requires gdbserver itself to be built as a 64-bit executable.)
2849 - gdbserver uses the new noack protocol mode for TCP connections to
2850 reduce communications latency, if also supported and enabled in GDB.
2852 - Support for the sparc64-linux-gnu target is now included in
2855 - The amd64-linux build of gdbserver now supports debugging both
2856 32-bit and 64-bit programs.
2858 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2859 now support hardware watchpoints, and will use them automatically
2864 GDB now has support for scripting using Python. Whether this is
2865 available is determined at configure time.
2867 New GDB commands can now be written in Python.
2869 * Ada tasking support
2871 Ada tasks can now be inspected in GDB. The following commands have
2875 Print the list of Ada tasks.
2877 Print detailed information about task number N.
2879 Print the task number of the current task.
2881 Switch the context of debugging to task number N.
2883 * Support for user-defined prefixed commands. The "define" command can
2884 add new commands to existing prefixes, e.g. "target".
2886 * Multi-inferior, multi-process debugging.
2888 GDB now has generalized support for multi-inferior debugging. See
2889 "Debugging Multiple Inferiors" in the manual for more information.
2890 Although availability still depends on target support, the command
2891 set is more uniform now. The GNU/Linux specific multi-forks support
2892 has been migrated to this new framework. This implied some user
2893 visible changes; see "New commands" and also "Removed commands"
2896 * Target descriptions can now describe the target OS ABI. See the
2897 "Target Description Format" section in the user manual for more
2900 * Target descriptions can now describe "compatible" architectures
2901 to indicate that the target can execute applications for a different
2902 architecture in addition to those for the main target architecture.
2903 See the "Target Description Format" section in the user manual for
2906 * Multi-architecture debugging.
2908 GDB now includes general supports for debugging applications on
2909 hybrid systems that use more than one single processor architecture
2910 at the same time. Each such hybrid architecture still requires
2911 specific support to be added. The only hybrid architecture supported
2912 in this version of GDB is the Cell Broadband Engine.
2914 * GDB now supports integrated debugging of Cell/B.E. applications that
2915 use both the PPU and SPU architectures. To enable support for hybrid
2916 Cell/B.E. debugging, you need to configure GDB to support both the
2917 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2918 --enable-targets configure option.
2920 * Non-stop mode debugging.
2922 For some targets, GDB now supports an optional mode of operation in
2923 which you can examine stopped threads while other threads continue
2924 to execute freely. This is referred to as non-stop mode, with the
2925 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2926 section in the user manual for more information.
2928 To be able to support remote non-stop debugging, a remote stub needs
2929 to implement the non-stop mode remote protocol extensions, as
2930 described in the "Remote Non-Stop" section of the user manual. The
2931 GDB remote stub, gdbserver, has been adjusted to support these
2932 extensions on linux targets.
2934 * New commands (for set/show, see "New options" below)
2936 catch syscall [NAME(S) | NUMBER(S)]
2937 Catch system calls. Arguments, which should be names of system
2938 calls or their numbers, mean catch only those syscalls. Without
2939 arguments, every syscall will be caught. When the inferior issues
2940 any of the specified syscalls, GDB will stop and announce the system
2941 call, both when it is called and when its call returns. This
2942 feature is currently available with a native GDB running on the
2943 Linux Kernel, under the following architectures: x86, x86_64,
2944 PowerPC and PowerPC64.
2946 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2948 Search memory for a sequence of bytes.
2950 maint set python print-stack
2951 maint show python print-stack
2952 Show a stack trace when an error is encountered in a Python script.
2955 Invoke CODE by passing it to the Python interpreter.
2960 These allow macros to be defined, undefined, and listed
2964 Show operating system information about processes.
2967 List the inferiors currently under GDB's control.
2970 Switch focus to inferior number NUM.
2973 Detach from inferior number NUM.
2976 Kill inferior number NUM.
2980 set spu stop-on-load
2981 show spu stop-on-load
2982 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2984 set spu auto-flush-cache
2985 show spu auto-flush-cache
2986 Control whether to automatically flush the software-managed cache
2987 during Cell/B.E. debugging.
2989 set sh calling-convention
2990 show sh calling-convention
2991 Control the calling convention used when calling SH target functions.
2994 show debug timestamp
2995 Control display of timestamps with GDB debugging output.
2997 set disassemble-next-line
2998 show disassemble-next-line
2999 Control display of disassembled source lines or instructions when
3002 set remote noack-packet
3003 show remote noack-packet
3004 Set/show the use of remote protocol QStartNoAckMode packet. See above
3005 under "New remote packets."
3007 set remote query-attached-packet
3008 show remote query-attached-packet
3009 Control use of remote protocol `qAttached' (query-attached) packet.
3011 set remote read-siginfo-object
3012 show remote read-siginfo-object
3013 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3016 set remote write-siginfo-object
3017 show remote write-siginfo-object
3018 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3021 set remote reverse-continue
3022 show remote reverse-continue
3023 Control use of remote protocol 'bc' (reverse-continue) packet.
3025 set remote reverse-step
3026 show remote reverse-step
3027 Control use of remote protocol 'bs' (reverse-step) packet.
3029 set displaced-stepping
3030 show displaced-stepping
3031 Control displaced stepping mode. Displaced stepping is a way to
3032 single-step over breakpoints without removing them from the debuggee.
3033 Also known as "out-of-line single-stepping".
3036 show debug displaced
3037 Control display of debugging info for displaced stepping.
3039 maint set internal-error
3040 maint show internal-error
3041 Control what GDB does when an internal error is detected.
3043 maint set internal-warning
3044 maint show internal-warning
3045 Control what GDB does when an internal warning is detected.
3050 Use a wrapper program to launch programs for debugging.
3052 set multiple-symbols (all|ask|cancel)
3053 show multiple-symbols
3054 The value of this variable can be changed to adjust the debugger behavior
3055 when an expression or a breakpoint location contains an ambiguous symbol
3056 name (an overloaded function name, for instance).
3058 set breakpoint always-inserted
3059 show breakpoint always-inserted
3060 Keep breakpoints always inserted in the target, as opposed to inserting
3061 them when resuming the target, and removing them when the target stops.
3062 This option can improve debugger performance on slow remote targets.
3064 set arm fallback-mode (arm|thumb|auto)
3065 show arm fallback-mode
3066 set arm force-mode (arm|thumb|auto)
3068 These commands control how ARM GDB determines whether instructions
3069 are ARM or Thumb. The default for both settings is auto, which uses
3070 the current CPSR value for instructions without symbols; previous
3071 versions of GDB behaved as if "set arm fallback-mode arm".
3073 set disable-randomization
3074 show disable-randomization
3075 Standalone programs run with the virtual address space randomization enabled
3076 by default on some platforms. This option keeps the addresses stable across
3077 multiple debugging sessions.
3081 Control whether other threads are stopped or not when some thread hits
3086 Requests that asynchronous execution is enabled in the target, if available.
3087 In this case, it's possible to resume target in the background, and interact
3088 with GDB while the target is running. "show target-async" displays the
3089 current state of asynchronous execution of the target.
3091 set target-wide-charset
3092 show target-wide-charset
3093 The target-wide-charset is the name of the character set that GDB
3094 uses when printing characters whose type is wchar_t.
3096 set tcp auto-retry (on|off)
3098 set tcp connect-timeout
3099 show tcp connect-timeout
3100 These commands allow GDB to retry failed TCP connections to a remote stub
3101 with a specified timeout period; this is useful if the stub is launched
3102 in parallel with GDB but may not be ready to accept connections immediately.
3104 set libthread-db-search-path
3105 show libthread-db-search-path
3106 Control list of directories which GDB will search for appropriate
3109 set schedule-multiple (on|off)
3110 show schedule-multiple
3111 Allow GDB to resume all threads of all processes or only threads of
3112 the current process.
3116 Use more aggressive caching for accesses to the stack. This improves
3117 performance of remote debugging (particularly backtraces) without
3118 affecting correctness.
3120 set interactive-mode (on|off|auto)
3121 show interactive-mode
3122 Control whether GDB runs in interactive mode (on) or not (off).
3123 When in interactive mode, GDB waits for the user to answer all
3124 queries. Otherwise, GDB does not wait and assumes the default
3125 answer. When set to auto (the default), GDB determines which
3126 mode to use based on the stdin settings.
3131 For program forks, this is replaced by the new more generic `info
3132 inferiors' command. To list checkpoints, you can still use the
3133 `info checkpoints' command, which was an alias for the `info forks'
3137 Replaced by the new `inferior' command. To switch between
3138 checkpoints, you can still use the `restart' command, which was an
3139 alias for the `fork' command.
3142 This is removed, since some targets don't have a notion of
3143 processes. To switch between processes, you can still use the
3144 `inferior' command using GDB's own inferior number.
3147 For program forks, this is replaced by the new more generic `kill
3148 inferior' command. To delete a checkpoint, you can still use the
3149 `delete checkpoint' command, which was an alias for the `delete
3153 For program forks, this is replaced by the new more generic `detach
3154 inferior' command. To detach a checkpoint, you can still use the
3155 `detach checkpoint' command, which was an alias for the `detach
3158 * New native configurations
3160 x86/x86_64 Darwin i[34567]86-*-darwin*
3162 x86_64 MinGW x86_64-*-mingw*
3166 Lattice Mico32 lm32-*
3167 x86 DICOS i[34567]86-*-dicos*
3168 x86_64 DICOS x86_64-*-dicos*
3171 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3172 (mingw32ce) debugging.
3178 These commands were actually not implemented on any target.
3180 *** Changes in GDB 6.8
3182 * New native configurations
3184 NetBSD/hppa hppa*-*netbsd*
3185 Xtensa GNU/Linux xtensa*-*-linux*
3189 NetBSD/hppa hppa*-*-netbsd*
3190 Xtensa GNU/Lunux xtensa*-*-linux*
3192 * Change in command line behavior -- corefiles vs. process ids.
3194 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3195 attaching to process NUMBER fails, GDB no longer attempts to open a
3196 core file named NUMBER. Attaching to a program using the -c option
3197 is no longer supported. Instead, use the '-p' or '--pid' options.
3199 * GDB can now be built as a native debugger for debugging Windows x86
3200 (mingw32) Portable Executable (PE) programs.
3202 * Pending breakpoints no longer change their number when their address
3205 * GDB now supports breakpoints with multiple locations,
3206 including breakpoints on C++ constructors, inside C++ templates,
3207 and in inlined functions.
3209 * GDB's ability to debug optimized code has been improved. GDB more
3210 accurately identifies function bodies and lexical blocks that occupy
3211 more than one contiguous range of addresses.
3213 * Target descriptions can now describe registers for PowerPC.
3215 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3216 registers on PowerPC targets.
3218 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3219 targets even when the libthread_db library is not available.
3221 * The GDB remote stub, gdbserver, now supports the new file transfer
3222 commands (remote put, remote get, and remote delete).
3224 * The GDB remote stub, gdbserver, now supports run and attach in
3225 extended-remote mode.
3227 * hppa*64*-*-hpux11* target broken
3228 The debugger is unable to start a program and fails with the following
3229 error: "Error trying to get information about dynamic linker".
3230 The gdb-6.7 release is also affected.
3232 * GDB now supports the --enable-targets= configure option to allow
3233 building a single GDB executable that supports multiple remote
3234 target architectures.
3236 * GDB now supports debugging C and C++ programs which use the
3237 Decimal Floating Point extension. In addition, the PowerPC target
3238 now has a set of pseudo-registers to inspect decimal float values
3239 stored in two consecutive float registers.
3241 * The -break-insert MI command can optionally create pending
3244 * Improved support for debugging Ada
3245 Many improvements to the Ada language support have been made. These
3247 - Better support for Ada2005 interface types
3248 - Improved handling of arrays and slices in general
3249 - Better support for Taft-amendment types
3250 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3252 - Improved command completion in Ada
3255 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3260 set print frame-arguments (all|scalars|none)
3261 show print frame-arguments
3262 The value of this variable can be changed to control which argument
3263 values should be printed by the debugger when displaying a frame.
3268 Transfer files to and from a remote target, and delete remote files.
3275 Transfer files to and from a remote target, and delete remote files.
3277 * New remote packets
3284 Open, close, read, write, and delete files on the remote system.
3287 Attach to an existing process on the remote system, in extended-remote
3291 Run a new process on the remote system, in extended-remote mode.
3293 *** Changes in GDB 6.7
3295 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3296 bfd, libiberty and opcodes, as revealed by static analysis donated by
3297 Coverity, Inc. (http://scan.coverity.com).
3299 * When looking up multiply-defined global symbols, GDB will now prefer the
3300 symbol definition in the current shared library if it was built using the
3301 -Bsymbolic linker option.
3303 * When the Text User Interface (TUI) is not configured, GDB will now
3304 recognize the -tui command-line option and print a message that the TUI
3307 * The GDB remote stub, gdbserver, now has lower overhead for high
3308 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3310 * GDB for MIPS targets now autodetects whether a remote target provides
3311 32-bit or 64-bit register values.
3313 * Support for C++ member pointers has been improved.
3315 * GDB now understands XML target descriptions, which specify the
3316 target's overall architecture. GDB can read a description from
3317 a local file or over the remote serial protocol.
3319 * Vectors of single-byte data use a new integer type which is not
3320 automatically displayed as character or string data.
3322 * The /s format now works with the print command. It displays
3323 arrays of single-byte integers and pointers to single-byte integers
3326 * Target descriptions can now describe target-specific registers,
3327 for architectures which have implemented the support (currently
3328 only ARM, M68K, and MIPS).
3330 * GDB and the GDB remote stub, gdbserver, now support the XScale
3333 * The GDB remote stub, gdbserver, has been updated to support
3334 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3335 has been rewritten to use the standard GDB remote protocol.
3337 * GDB can now step into C++ functions which are called through thunks.
3339 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3341 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3342 layout. It also supports a TextSeg= and DataSeg= response when only
3343 segment base addresses (rather than offsets) are available.
3345 * The /i format now outputs any trailing branch delay slot instructions
3346 immediately following the last instruction within the count specified.
3348 * The GDB remote protocol "T" stop reply packet now supports a
3349 "library" response. Combined with the new "qXfer:libraries:read"
3350 packet, this response allows GDB to debug shared libraries on targets
3351 where the operating system manages the list of loaded libraries (e.g.
3352 Windows and SymbianOS).
3354 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3355 (DLLs) on Windows and Windows CE targets.
3357 * GDB now supports a faster verification that a .debug file matches its binary
3358 according to its build-id signature, if the signature is present.
3364 Enable or disable hardware flow control (RTS/CTS) on the serial port
3365 when debugging using remote targets.
3367 set mem inaccessible-by-default
3368 show mem inaccessible-by-default
3369 If the target supplies a memory map, for instance via the remote
3370 protocol's "qXfer:memory-map:read" packet, setting this variable
3371 prevents GDB from accessing memory outside the memory map. This
3372 is useful for targets with memory mapped registers or which react
3373 badly to accesses of unmapped address space.
3375 set breakpoint auto-hw
3376 show breakpoint auto-hw
3377 If the target supplies a memory map, for instance via the remote
3378 protocol's "qXfer:memory-map:read" packet, setting this variable
3379 lets GDB use hardware breakpoints automatically for memory regions
3380 where it can not use software breakpoints. This covers both the
3381 "break" command and internal breakpoints used for other commands
3382 including "next" and "finish".
3385 catch exception unhandled
3386 Stop the program execution when Ada exceptions are raised.
3389 Stop the program execution when an Ada assertion failed.
3393 Set an alternate system root for target files. This is a more
3394 general version of "set solib-absolute-prefix", which is now
3395 an alias to "set sysroot".
3398 Provide extended SPU facility status information. This set of
3399 commands is available only when debugging the Cell/B.E. SPU
3402 * New native configurations
3404 OpenBSD/sh sh*-*openbsd*
3407 unset tdesc filename
3409 Use the specified local file as an XML target description, and do
3410 not query the target for its built-in description.
3414 OpenBSD/sh sh*-*-openbsd*
3415 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3416 Toshiba Media Processor mep-elf
3418 * New remote packets
3421 Ignore the specified signals; pass them directly to the debugged program
3422 without stopping other threads or reporting them to GDB.
3424 qXfer:features:read:
3425 Read an XML target description from the target, which describes its
3430 Read or write contents of an spufs file on the target system. These
3431 packets are available only on the Cell/B.E. SPU architecture.
3433 qXfer:libraries:read:
3434 Report the loaded shared libraries. Combined with new "T" packet
3435 response, this packet allows GDB to debug shared libraries on
3436 targets where the operating system manages the list of loaded
3437 libraries (e.g. Windows and SymbianOS).
3441 Support for these obsolete configurations has been removed.
3449 i[34567]86-*-lynxos*
3450 i[34567]86-*-netware*
3451 i[34567]86-*-sco3.2v5*
3452 i[34567]86-*-sco3.2v4*
3454 i[34567]86-*-sysv4.2*
3457 i[34567]86-*-unixware2*
3458 i[34567]86-*-unixware*
3467 * Other removed features
3474 Various m68k-only ROM monitors.
3481 Various Renesas ROM monitors and debugging interfaces for SH and
3486 Support for a Macraigor serial interface to on-chip debugging.
3487 GDB does not directly support the newer parallel or USB
3492 A debug information format. The predecessor to DWARF 2 and
3493 DWARF 3, which are still supported.
3495 Support for the HP aCC compiler on HP-UX/PA-RISC
3497 SOM-encapsulated symbolic debugging information, automatic
3498 invocation of pxdb, and the aCC custom C++ ABI. This does not
3499 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3500 with aCC can still be debugged on an assembly level.
3502 MIPS ".pdr" sections
3504 A MIPS-specific format used to describe stack frame layout
3505 in debugging information.
3509 GDB could work with an older version of Guile to debug
3510 the interpreter and Scheme programs running in it.
3512 set mips stack-arg-size
3513 set mips saved-gpreg-size
3515 Use "set mips abi" to control parameter passing for MIPS.
3517 *** Changes in GDB 6.6
3522 Cell Broadband Engine SPU spu-elf
3524 * GDB can now be configured as a cross-debugger targeting native Windows
3525 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3526 running on a Windows system over TCP/IP to debug Windows programs.
3528 * The GDB remote stub, gdbserver, has been updated to support Windows and
3529 Cygwin debugging. Both single-threaded and multi-threaded programs are
3532 * The "set trust-readonly-sections" command works again. This command was
3533 broken in GDB 6.3, 6.4, and 6.5.
3535 * The "load" command now supports writing to flash memory, if the remote
3536 stub provides the required support.
3538 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3539 longer requires symbolic debug information (e.g. DWARF-2).
3544 unset substitute-path
3545 show substitute-path
3546 Manage a list of substitution rules that GDB uses to rewrite the name
3547 of the directories where the sources are located. This can be useful
3548 for instance when the sources were moved to a different location
3549 between compilation and debugging.
3553 Print each CLI command as it is executed. Each command is prefixed with
3554 a number of `+' symbols representing the nesting depth.
3555 The source command now has a `-v' option to enable the same feature.
3559 The ARM Demon monitor support (RDP protocol, "target rdp").
3561 Kernel Object Display, an embedded debugging feature which only worked with
3562 an obsolete version of Cisco IOS.
3564 The 'set download-write-size' and 'show download-write-size' commands.
3566 * New remote packets
3569 Tell a stub about GDB client features, and request remote target features.
3570 The first feature implemented is PacketSize, which allows the target to
3571 specify the size of packets it can handle - to minimize the number of
3572 packets required and improve performance when connected to a remote
3576 Fetch an OS auxilliary vector from the remote stub. This packet is a
3577 more efficient replacement for qPart:auxv:read.
3579 qXfer:memory-map:read:
3580 Fetch a memory map from the remote stub, including information about
3581 RAM, ROM, and flash memory devices.
3586 Erase and program a flash memory device.
3588 * Removed remote packets
3591 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3592 used it, and only gdbserver implemented it.
3594 *** Changes in GDB 6.5
3598 Renesas M32C/M16C m32c-elf
3600 Morpho Technologies ms1 ms1-elf
3604 init-if-undefined Initialize a convenience variable, but
3605 only if it doesn't already have a value.
3607 The following commands are presently only implemented for native GNU/Linux:
3609 checkpoint Save a snapshot of the program state.
3611 restart <n> Return the program state to a
3612 previously saved state.
3614 info checkpoints List currently saved checkpoints.
3616 delete-checkpoint <n> Delete a previously saved checkpoint.
3618 set|show detach-on-fork Tell gdb whether to detach from a newly
3619 forked process, or to keep debugging it.
3621 info forks List forks of the user program that
3622 are available to be debugged.
3624 fork <n> Switch to debugging one of several
3625 forks of the user program that are
3626 available to be debugged.
3628 delete-fork <n> Delete a fork from the list of forks
3629 that are available to be debugged (and
3630 kill the forked process).
3632 detach-fork <n> Delete a fork from the list of forks
3633 that are available to be debugged (and
3634 allow the process to continue).
3638 Morpho Technologies ms2 ms1-elf
3640 * Improved Windows host support
3642 GDB now builds as a cross debugger hosted on i686-mingw32, including
3643 native console support, and remote communications using either
3644 network sockets or serial ports.
3646 * Improved Modula-2 language support
3648 GDB can now print most types in the Modula-2 syntax. This includes:
3649 basic types, set types, record types, enumerated types, range types,
3650 pointer types and ARRAY types. Procedure var parameters are correctly
3651 printed and hexadecimal addresses and character constants are also
3652 written in the Modula-2 syntax. Best results can be obtained by using
3653 GNU Modula-2 together with the -gdwarf-2 command line option.
3657 The ARM rdi-share module.
3659 The Netware NLM debug server.
3661 *** Changes in GDB 6.4
3663 * New native configurations
3665 OpenBSD/arm arm*-*-openbsd*
3666 OpenBSD/mips64 mips64-*-openbsd*
3670 Morpho Technologies ms1 ms1-elf
3672 * New command line options
3674 --batch-silent As for --batch, but totally silent.
3675 --return-child-result The debugger will exist with the same value
3676 the child (debugged) program exited with.
3677 --eval-command COMMAND, -ex COMMAND
3678 Execute a single GDB CLI command. This may be
3679 specified multiple times and in conjunction
3680 with the --command (-x) option.
3682 * Deprecated commands removed
3684 The following commands, that were deprecated in 2000, have been
3688 set|show arm disassembly-flavor set|show arm disassembler
3689 othernames set arm disassembler
3690 set|show remotedebug set|show debug remote
3691 set|show archdebug set|show debug arch
3692 set|show eventdebug set|show debug event
3695 * New BSD user-level threads support
3697 It is now possible to debug programs using the user-level threads
3698 library on OpenBSD and FreeBSD. Currently supported (target)
3701 FreeBSD/amd64 x86_64-*-freebsd*
3702 FreeBSD/i386 i386-*-freebsd*
3703 OpenBSD/i386 i386-*-openbsd*
3705 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3706 are not yet supported.
3708 * New support for Matsushita MN10300 w/sim added
3709 (Work in progress). mn10300-elf.
3711 * REMOVED configurations and files
3713 VxWorks and the XDR protocol *-*-vxworks
3714 Motorola MCORE mcore-*-*
3715 National Semiconductor NS32000 ns32k-*-*
3717 * New "set print array-indexes" command
3719 After turning this setting "on", GDB prints the index of each element
3720 when displaying arrays. The default is "off" to preserve the previous
3723 * VAX floating point support
3725 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3727 * User-defined command support
3729 In addition to using $arg0..$arg9 for argument passing, it is now possible
3730 to use $argc to determine now many arguments have been passed. See the
3731 section on user-defined commands in the user manual for more information.
3733 *** Changes in GDB 6.3:
3735 * New command line option
3737 GDB now accepts -l followed by a number to set the timeout for remote
3740 * GDB works with GCC -feliminate-dwarf2-dups
3742 GDB now supports a more compact representation of DWARF-2 debug
3743 information using DW_FORM_ref_addr references. These are produced
3744 by GCC with the option -feliminate-dwarf2-dups and also by some
3745 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3746 to use -feliminate-dwarf2-dups.
3748 * Internationalization
3750 When supported by the host system, GDB will be built with
3751 internationalization (libintl). The task of marking up the sources is
3752 continued, we're looking forward to our first translation.
3756 Initial support for debugging programs compiled with the GNAT
3757 implementation of the Ada programming language has been integrated
3758 into GDB. In this release, support is limited to expression evaluation.
3760 * New native configurations
3762 GNU/Linux/m32r m32r-*-linux-gnu
3766 GDB's remote protocol now includes support for the 'p' packet. This
3767 packet is used to fetch individual registers from a remote inferior.
3769 * END-OF-LIFE registers[] compatibility module
3771 GDB's internal register infrastructure has been completely rewritten.
3772 The new infrastructure making possible the implementation of key new
3773 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3776 GDB 6.3 will be the last release to include the the registers[]
3777 compatibility module that allowed out-of-date configurations to
3778 continue to work. This change directly impacts the following
3788 powerpc bdm protocol
3790 Unless there is activity to revive these configurations, they will be
3791 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3793 * OBSOLETE configurations and files
3795 Configurations that have been declared obsolete in this release have
3796 been commented out. Unless there is activity to revive these
3797 configurations, the next release of GDB will have their sources
3798 permanently REMOVED.
3807 *** Changes in GDB 6.2.1:
3809 * MIPS `break main; run' gave an heuristic-fence-post warning
3811 When attempting to run even a simple program, a warning about
3812 heuristic-fence-post being hit would be reported. This problem has
3815 * MIPS IRIX 'long double' crashed GDB
3817 When examining a long double variable, GDB would get a segmentation
3818 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3819 IRIX long double values).
3823 A bug in the VAX stack code was causing problems with the "next"
3824 command. This problem has been fixed.
3826 *** Changes in GDB 6.2:
3828 * Fix for ``many threads''
3830 On GNU/Linux systems that use the NPTL threads library, a program
3831 rapidly creating and deleting threads would confuse GDB leading to the
3834 ptrace: No such process.
3835 thread_db_get_info: cannot get thread info: generic error
3837 This problem has been fixed.
3839 * "-async" and "-noasync" options removed.
3841 Support for the broken "-noasync" option has been removed (it caused
3844 * New ``start'' command.
3846 This command runs the program until the begining of the main procedure.
3848 * New BSD Kernel Data Access Library (libkvm) interface
3850 Using ``target kvm'' it is now possible to debug kernel core dumps and
3851 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3852 platforms. Currently supported (native-only) configurations are:
3854 FreeBSD/amd64 x86_64-*-freebsd*
3855 FreeBSD/i386 i?86-*-freebsd*
3856 NetBSD/i386 i?86-*-netbsd*
3857 NetBSD/m68k m68*-*-netbsd*
3858 NetBSD/sparc sparc-*-netbsd*
3859 OpenBSD/amd64 x86_64-*-openbsd*
3860 OpenBSD/i386 i?86-*-openbsd*
3861 OpenBSD/m68k m68*-openbsd*
3862 OpenBSD/sparc sparc-*-openbsd*
3864 * Signal trampoline code overhauled
3866 Many generic problems with GDB's signal handling code have been fixed.
3867 These include: backtraces through non-contiguous stacks; recognition
3868 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3869 call; backtrace through a signal trampoline; step into and out of
3870 signal handlers; and single-stepping in the signal trampoline.
3872 Please note that kernel bugs are a limiting factor here. These
3873 features have been shown to work on an s390 GNU/Linux system that
3874 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3876 * Cygwin support for DWARF 2 added.
3878 * New native configurations
3880 GNU/Linux/hppa hppa*-*-linux*
3881 OpenBSD/hppa hppa*-*-openbsd*
3882 OpenBSD/m68k m68*-*-openbsd*
3883 OpenBSD/m88k m88*-*-openbsd*
3884 OpenBSD/powerpc powerpc-*-openbsd*
3885 NetBSD/vax vax-*-netbsd*
3886 OpenBSD/vax vax-*-openbsd*
3888 * END-OF-LIFE frame compatibility module
3890 GDB's internal frame infrastructure has been completely rewritten.
3891 The new infrastructure making it possible to support key new features
3892 including DWARF 2 Call Frame Information. To aid in the task of
3893 migrating old configurations to this new infrastructure, a
3894 compatibility module, that allowed old configurations to continue to
3895 work, was also included.
3897 GDB 6.2 will be the last release to include this frame compatibility
3898 module. This change directly impacts the following configurations:
3908 Unless there is activity to revive these configurations, they will be
3909 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3911 * REMOVED configurations and files
3913 Sun 3, running SunOS 3 m68*-*-sunos3*
3914 Sun 3, running SunOS 4 m68*-*-sunos4*
3915 Sun 2, running SunOS 3 m68000-*-sunos3*
3916 Sun 2, running SunOS 4 m68000-*-sunos4*
3917 Motorola 680x0 running LynxOS m68*-*-lynxos*
3918 AT&T 3b1/Unix pc m68*-att-*
3919 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3920 decstation mips-dec-* mips-little-*
3921 riscos mips-*-riscos* mips-*-sysv*
3922 sonymips mips-sony-*
3923 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3925 *** Changes in GDB 6.1.1:
3927 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3929 The TUI (Text-mode User Interface) is now built as part of a default
3930 GDB configuration. It is enabled by either selecting the TUI with the
3931 command line option "-i=tui" or by running the separate "gdbtui"
3932 program. For more information on the TUI, see the manual "Debugging
3935 * Pending breakpoint support (also included in GDB 6.1)
3937 Support has been added to allow you to specify breakpoints in shared
3938 libraries that have not yet been loaded. If a breakpoint location
3939 cannot be found, and the "breakpoint pending" option is set to auto,
3940 GDB queries you if you wish to make the breakpoint pending on a future
3941 shared-library load. If and when GDB resolves the breakpoint symbol,
3942 the pending breakpoint is removed as one or more regular breakpoints
3945 Pending breakpoints are very useful for GCJ Java debugging.
3947 * Fixed ISO-C build problems
3949 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3950 non ISO-C code that stopped them being built using a more strict ISO-C
3951 compiler (e.g., IBM's C compiler).
3953 * Fixed build problem on IRIX 5
3955 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3956 wasn't able to compile compile on an IRIX 5 system.
3958 * Added execute permission to gdb/gdbserver/configure
3960 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3961 permission. This bug would cause configure to fail on a number of
3962 systems (Solaris, IRIX). Ref: server/519.
3964 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3966 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3967 has been updated to use constant array sizes.
3969 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3971 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3972 its generated DWARF Call Frame Info. This encoding was causing GDB to
3973 panic, that panic has been fixed. Ref: gdb/1628.
3975 * Fixed a problem when examining parameters in shared library code.
3977 When examining parameters in optimized shared library code generated
3978 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3979 not available''. GDB now correctly displays the variable's value.
3981 *** Changes in GDB 6.1:
3983 * Removed --with-mmalloc
3985 Support for the mmalloc memory manager has been removed, as it
3986 conflicted with the internal gdb byte cache.
3988 * Changes in AMD64 configurations
3990 The AMD64 target now includes the %cs and %ss registers. As a result
3991 the AMD64 remote protocol has changed; this affects the floating-point
3992 and SSE registers. If you rely on those registers for your debugging,
3993 you should upgrade gdbserver on the remote side.
3995 * Revised SPARC target
3997 The SPARC target has been completely revised, incorporating the
3998 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3999 support for LynxOS and SunOS 4 has been dropped. Calling functions
4000 from within GDB on operating systems with a non-executable stack
4001 (Solaris, OpenBSD) now works.
4005 GDB has a new C++ demangler which does a better job on the mangled
4006 names generated by current versions of g++. It also runs faster, so
4007 with this and other changes gdb should now start faster on large C++
4010 * DWARF 2 Location Expressions
4012 GDB support for location expressions has been extended to support function
4013 arguments and frame bases. Older versions of GDB could crash when they
4016 * C++ nested types and namespaces
4018 GDB's support for nested types and namespaces in C++ has been
4019 improved, especially if you use the DWARF 2 debugging format. (This
4020 is the default for recent versions of GCC on most platforms.)
4021 Specifically, if you have a class "Inner" defined within a class or
4022 namespace "Outer", then GDB realizes that the class's name is
4023 "Outer::Inner", not simply "Inner". This should greatly reduce the
4024 frequency of complaints about not finding RTTI symbols. In addition,
4025 if you are stopped at inside of a function defined within a namespace,
4026 GDB modifies its name lookup accordingly.
4028 * New native configurations
4030 NetBSD/amd64 x86_64-*-netbsd*
4031 OpenBSD/amd64 x86_64-*-openbsd*
4032 OpenBSD/alpha alpha*-*-openbsd*
4033 OpenBSD/sparc sparc-*-openbsd*
4034 OpenBSD/sparc64 sparc64-*-openbsd*
4036 * New debugging protocols
4038 M32R with SDI protocol m32r-*-elf*
4040 * "set prompt-escape-char" command deleted.
4042 The command "set prompt-escape-char" has been deleted. This command,
4043 and its very obscure effet on GDB's prompt, was never documented,
4044 tested, nor mentioned in the NEWS file.
4046 * OBSOLETE configurations and files
4048 Configurations that have been declared obsolete in this release have
4049 been commented out. Unless there is activity to revive these
4050 configurations, the next release of GDB will have their sources
4051 permanently REMOVED.
4053 Sun 3, running SunOS 3 m68*-*-sunos3*
4054 Sun 3, running SunOS 4 m68*-*-sunos4*
4055 Sun 2, running SunOS 3 m68000-*-sunos3*
4056 Sun 2, running SunOS 4 m68000-*-sunos4*
4057 Motorola 680x0 running LynxOS m68*-*-lynxos*
4058 AT&T 3b1/Unix pc m68*-att-*
4059 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4060 decstation mips-dec-* mips-little-*
4061 riscos mips-*-riscos* mips-*-sysv*
4062 sonymips mips-sony-*
4063 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4065 * REMOVED configurations and files
4067 SGI Irix-4.x mips-sgi-irix4 or iris4
4068 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4069 Z8000 simulator z8k-zilog-none or z8ksim
4070 Matsushita MN10200 w/simulator mn10200-*-*
4071 H8/500 simulator h8500-hitachi-hms or h8500hms
4072 HP/PA running BSD hppa*-*-bsd*
4073 HP/PA running OSF/1 hppa*-*-osf*
4074 HP/PA Pro target hppa*-*-pro*
4075 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4076 386BSD i[3456]86-*-bsd*
4077 Sequent family i[3456]86-sequent-sysv4*
4078 i[3456]86-sequent-sysv*
4079 i[3456]86-sequent-bsd*
4080 SPARC running LynxOS sparc-*-lynxos*
4081 SPARC running SunOS 4 sparc-*-sunos4*
4082 Tsqware Sparclet sparclet-*-*
4083 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4085 *** Changes in GDB 6.0:
4089 Support for debugging the Objective-C programming language has been
4090 integrated into GDB.
4092 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4094 DWARF 2's Call Frame Information makes available compiler generated
4095 information that more exactly describes the program's run-time stack.
4096 By using this information, GDB is able to provide more robust stack
4099 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4100 have been updated to use a new backtrace mechanism which includes
4101 DWARF 2 CFI support.
4105 GDB's remote protocol has been extended to include support for hosted
4106 file I/O (where the remote target uses GDB's file system). See GDB's
4107 remote protocol documentation for details.
4109 * All targets using the new architecture framework.
4111 All of GDB's targets have been updated to use the new internal
4112 architecture framework. The way is now open for future GDB releases
4113 to include cross-architecture native debugging support (i386 on amd64,
4116 * GNU/Linux's Thread Local Storage (TLS)
4118 GDB now includes support for for the GNU/Linux implementation of
4119 per-thread variables.
4121 * GNU/Linux's Native POSIX Thread Library (NPTL)
4123 GDB's thread code has been updated to work with either the new
4124 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4126 * Separate debug info.
4128 GDB, in conjunction with BINUTILS, now supports a mechanism for
4129 automatically loading debug information from a separate file. Instead
4130 of shipping full debug and non-debug versions of system libraries,
4131 system integrators can now instead ship just the stripped libraries
4132 and optional debug files.
4134 * DWARF 2 Location Expressions
4136 DWARF 2 Location Expressions allow the compiler to more completely
4137 describe the location of variables (even in optimized code) to the
4140 GDB now includes preliminary support for location expressions (support
4141 for DW_OP_piece is still missing).
4145 A number of long standing bugs that caused GDB to die while starting a
4146 Java application have been fixed. GDB's Java support is now
4147 considered "useable".
4149 * GNU/Linux support for fork, vfork, and exec.
4151 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4152 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4155 * GDB supports logging output to a file
4157 There are two new commands, "set logging" and "show logging", which can be
4158 used to capture GDB's output to a file.
4160 * The meaning of "detach" has changed for gdbserver
4162 The "detach" command will now resume the application, as documented. To
4163 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4166 * d10v, m68hc11 `regs' command deprecated
4168 The `info registers' command has been updated so that it displays the
4169 registers using a format identical to the old `regs' command.
4173 A new command, "maint set profile on/off", has been added. This command can
4174 be used to enable or disable profiling while running GDB, to profile a
4175 session or a set of commands. In addition there is a new configure switch,
4176 "--enable-profiling", which will cause GDB to be compiled with profiling
4177 data, for more informative profiling results.
4179 * Default MI syntax changed to "mi2".
4181 The default MI (machine interface) syntax, enabled by the command line
4182 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4183 "mi1", can be enabled by specifying the option "-i=mi1".
4185 Support for the original "mi0" syntax (included in GDB 5.0) has been
4188 Fix for gdb/192: removed extraneous space when displaying frame level.
4189 Fix for gdb/672: update changelist is now output in mi list format.
4190 Fix for gdb/702: a -var-assign that updates the value now shows up
4191 in a subsequent -var-update.
4193 * New native configurations.
4195 FreeBSD/amd64 x86_64-*-freebsd*
4197 * Multi-arched targets.
4199 HP/PA HPUX11 hppa*-*-hpux*
4200 Renesas M32R/D w/simulator m32r-*-elf*
4202 * OBSOLETE configurations and files
4204 Configurations that have been declared obsolete in this release have
4205 been commented out. Unless there is activity to revive these
4206 configurations, the next release of GDB will have their sources
4207 permanently REMOVED.
4209 Z8000 simulator z8k-zilog-none or z8ksim
4210 Matsushita MN10200 w/simulator mn10200-*-*
4211 H8/500 simulator h8500-hitachi-hms or h8500hms
4212 HP/PA running BSD hppa*-*-bsd*
4213 HP/PA running OSF/1 hppa*-*-osf*
4214 HP/PA Pro target hppa*-*-pro*
4215 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4216 Sequent family i[3456]86-sequent-sysv4*
4217 i[3456]86-sequent-sysv*
4218 i[3456]86-sequent-bsd*
4219 Tsqware Sparclet sparclet-*-*
4220 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4222 * REMOVED configurations and files
4225 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4226 IBM AIX PS/2 i[3456]86-*-aix
4227 i386 running Mach 3.0 i[3456]86-*-mach3*
4228 i386 running Mach i[3456]86-*-mach*
4229 i386 running OSF/1 i[3456]86-*osf1mk*
4230 HP/Apollo 68k Family m68*-apollo*-sysv*,
4232 m68*-hp-bsd*, m68*-hp-hpux*
4233 Argonaut Risc Chip (ARC) arc-*-*
4234 Mitsubishi D30V d30v-*-*
4235 Fujitsu FR30 fr30-*-elf*
4236 OS/9000 i[34]86-*-os9k
4237 I960 with MON960 i960-*-coff
4239 * MIPS $fp behavior changed
4241 The convenience variable $fp, for the MIPS, now consistently returns
4242 the address of the current frame's base. Previously, depending on the
4243 context, $fp could refer to either $sp or the current frame's base
4244 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4245 The GNU Source-Level Debugger''.
4247 *** Changes in GDB 5.3:
4249 * GNU/Linux shared library multi-threaded performance improved.
4251 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4252 `/proc', in preference to `ptrace' for memory reads. This may result
4253 in an improvement in the start-up time of multi-threaded, shared
4254 library applications when run under GDB. One GDB user writes: ``loads
4255 shared libs like mad''.
4257 * ``gdbserver'' now supports multi-threaded applications on some targets
4259 Support for debugging multi-threaded applications which use
4260 the GNU/Linux LinuxThreads package has been added for
4261 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4262 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4264 * GDB now supports C/C++ preprocessor macros.
4266 GDB now expands preprocessor macro invocations in C/C++ expressions,
4267 and provides various commands for showing macro definitions and how
4270 The new command `macro expand EXPRESSION' expands any macro
4271 invocations in expression, and shows the result.
4273 The new command `show macro MACRO-NAME' shows the definition of the
4274 macro named MACRO-NAME, and where it was defined.
4276 Most compilers don't include information about macros in the debugging
4277 information by default. In GCC 3.1, for example, you need to compile
4278 your program with the options `-gdwarf-2 -g3'. If the macro
4279 information is present in the executable, GDB will read it.
4281 * Multi-arched targets.
4283 DEC Alpha (partial) alpha*-*-*
4284 DEC VAX (partial) vax-*-*
4286 National Semiconductor NS32000 (partial) ns32k-*-*
4287 Motorola 68000 (partial) m68k-*-*
4288 Motorola MCORE mcore-*-*
4292 Fujitsu FRV architecture added by Red Hat frv*-*-*
4295 * New native configurations
4297 Alpha NetBSD alpha*-*-netbsd*
4298 SH NetBSD sh*-*-netbsdelf*
4299 MIPS NetBSD mips*-*-netbsd*
4300 UltraSPARC NetBSD sparc64-*-netbsd*
4302 * OBSOLETE configurations and files
4304 Configurations that have been declared obsolete in this release have
4305 been commented out. Unless there is activity to revive these
4306 configurations, the next release of GDB will have their sources
4307 permanently REMOVED.
4309 Mitsubishi D30V d30v-*-*
4310 OS/9000 i[34]86-*-os9k
4311 IBM AIX PS/2 i[3456]86-*-aix
4312 Fujitsu FR30 fr30-*-elf*
4313 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4314 Argonaut Risc Chip (ARC) arc-*-*
4315 i386 running Mach 3.0 i[3456]86-*-mach3*
4316 i386 running Mach i[3456]86-*-mach*
4317 i386 running OSF/1 i[3456]86-*osf1mk*
4318 HP/Apollo 68k Family m68*-apollo*-sysv*,
4320 m68*-hp-bsd*, m68*-hp-hpux*
4321 I960 with MON960 i960-*-coff
4323 * OBSOLETE languages
4325 CHILL, a Pascal like language used by telecommunications companies.
4327 * REMOVED configurations and files
4329 AMD 29k family via UDI a29k-amd-udi, udi29k
4330 A29K VxWorks a29k-*-vxworks
4331 AMD 29000 embedded, using EBMON a29k-none-none
4332 AMD 29000 embedded with COFF a29k-none-coff
4333 AMD 29000 embedded with a.out a29k-none-aout
4335 testsuite/gdb.hp/gdb.threads-hp/ directory
4337 * New command "set max-user-call-depth <nnn>"
4339 This command allows the user to limit the call depth of user-defined
4340 commands. The default is 1024.
4342 * Changes in FreeBSD/i386 native debugging.
4344 Support for the "generate-core-file" has been added.
4346 * New commands "dump", "append", and "restore".
4348 These commands allow data to be copied from target memory
4349 to a bfd-format or binary file (dump and append), and back
4350 from a file into memory (restore).
4352 * Improved "next/step" support on multi-processor Alpha Tru64.
4354 The previous single-step mechanism could cause unpredictable problems,
4355 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4356 of a software single-step mechanism prevents this.
4358 *** Changes in GDB 5.2.1:
4366 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4367 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4368 Fix, by Joel Brobecker imported from mainline.
4370 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4371 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4372 Fix, by Fred Fish, imported from mainline.
4374 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4375 Surprisingly enough, it works now.
4376 By Michal Ludvig, imported from mainline.
4378 i386 hardware watchpoint support:
4379 avoid misses on second run for some targets.
4380 By Pierre Muller, imported from mainline.
4382 *** Changes in GDB 5.2:
4384 * New command "set trust-readonly-sections on[off]".
4386 This command is a hint that tells gdb that read-only sections
4387 really are read-only (ie. that their contents will not change).
4388 In this mode, gdb will go to the object file rather than the
4389 target to read memory from read-only sections (such as ".text").
4390 This can be a significant performance improvement on some
4391 (notably embedded) targets.
4393 * New command "generate-core-file" (or "gcore").
4395 This new gdb command allows the user to drop a core file of the child
4396 process state at any time. So far it's been implemented only for
4397 GNU/Linux and Solaris, but should be relatively easily ported to other
4398 hosts. Argument is core file name (defaults to core.<pid>).
4400 * New command line option
4402 GDB now accepts --pid or -p followed by a process id.
4404 * Change in command line behavior -- corefiles vs. process ids.
4406 There is a subtle behavior in the way in which GDB handles
4407 command line arguments. The first non-flag argument is always
4408 a program to debug, but the second non-flag argument may either
4409 be a corefile or a process id. Previously, GDB would attempt to
4410 open the second argument as a corefile, and if that failed, would
4411 issue a superfluous error message and then attempt to attach it as
4412 a process. Now, if the second argument begins with a non-digit,
4413 it will be treated as a corefile. If it begins with a digit,
4414 GDB will attempt to attach it as a process, and if no such process
4415 is found, will then attempt to open it as a corefile.
4417 * Changes in ARM configurations.
4419 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4420 configuration is fully multi-arch.
4422 * New native configurations
4424 ARM NetBSD arm*-*-netbsd*
4425 x86 OpenBSD i[3456]86-*-openbsd*
4426 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4427 Sparc64 running FreeBSD sparc64-*-freebsd*
4431 Sanyo XStormy16 xstormy16-elf
4433 * OBSOLETE configurations and files
4435 Configurations that have been declared obsolete in this release have
4436 been commented out. Unless there is activity to revive these
4437 configurations, the next release of GDB will have their sources
4438 permanently REMOVED.
4440 AMD 29k family via UDI a29k-amd-udi, udi29k
4441 A29K VxWorks a29k-*-vxworks
4442 AMD 29000 embedded, using EBMON a29k-none-none
4443 AMD 29000 embedded with COFF a29k-none-coff
4444 AMD 29000 embedded with a.out a29k-none-aout
4446 testsuite/gdb.hp/gdb.threads-hp/ directory
4448 * REMOVED configurations and files
4450 TI TMS320C80 tic80-*-*
4452 PowerPC Solaris powerpcle-*-solaris*
4453 PowerPC Windows NT powerpcle-*-cygwin32
4454 PowerPC Netware powerpc-*-netware*
4455 Harris/CXUX m88k m88*-harris-cxux*
4456 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4457 ns32k-utek-sysv* ns32k-utek-*
4458 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4459 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4460 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4461 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4462 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4464 * Changes to command line processing
4466 The new `--args' feature can be used to specify command-line arguments
4467 for the inferior from gdb's command line.
4469 * Changes to key bindings
4471 There is a new `operate-and-get-next' function bound to `C-o'.
4473 *** Changes in GDB 5.1.1
4475 Fix compile problem on DJGPP.
4477 Fix a problem with floating-point registers on the i386 being
4480 Fix to stop GDB crashing on .debug_str debug info.
4482 Numerous documentation fixes.
4484 Numerous testsuite fixes.
4486 *** Changes in GDB 5.1:
4488 * New native configurations
4490 Alpha FreeBSD alpha*-*-freebsd*
4491 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4492 MIPS GNU/Linux mips*-*-linux*
4493 MIPS SGI Irix 6.x mips*-sgi-irix6*
4494 ia64 AIX ia64-*-aix*
4495 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4499 Motorola 68HC11 and 68HC12 m68hc11-elf
4501 UltraSparc running GNU/Linux sparc64-*-linux*
4503 * OBSOLETE configurations and files
4505 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4506 Harris/CXUX m88k m88*-harris-cxux*
4507 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4508 ns32k-utek-sysv* ns32k-utek-*
4509 TI TMS320C80 tic80-*-*
4511 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4512 PowerPC Solaris powerpcle-*-solaris*
4513 PowerPC Windows NT powerpcle-*-cygwin32
4514 PowerPC Netware powerpc-*-netware*
4515 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4516 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4517 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4518 Apple Macintosh (MPW) host N/A
4520 stuff.c (Program to stuff files into a specially prepared space in kdb)
4521 kdb-start.c (Main loop for the standalone kernel debugger)
4523 Configurations that have been declared obsolete in this release have
4524 been commented out. Unless there is activity to revive these
4525 configurations, the next release of GDB will have their sources
4526 permanently REMOVED.
4528 * REMOVED configurations and files
4530 Altos 3068 m68*-altos-*
4531 Convex c1-*-*, c2-*-*
4533 ARM RISCix arm-*-* (as host)
4537 * GDB has been converted to ISO C.
4539 GDB's source code has been converted to ISO C. In particular, the
4540 sources are fully protoized, and rely on standard headers being
4545 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4547 * The MI enabled by default.
4549 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4550 revised and enabled by default. Packages which use GDB as a debugging
4551 engine behind a UI or another front end are encouraged to switch to
4552 using the GDB/MI interface, instead of the old annotations interface
4553 which is now deprecated.
4555 * Support for debugging Pascal programs.
4557 GDB now includes support for debugging Pascal programs. The following
4558 main features are supported:
4560 - Pascal-specific data types such as sets;
4562 - automatic recognition of Pascal sources based on file-name
4565 - Pascal-style display of data types, variables, and functions;
4567 - a Pascal expression parser.
4569 However, some important features are not yet supported.
4571 - Pascal string operations are not supported at all;
4573 - there are some problems with boolean types;
4575 - Pascal type hexadecimal constants are not supported
4576 because they conflict with the internal variables format;
4578 - support for Pascal objects and classes is not full yet;
4580 - unlike Pascal, GDB is case-sensitive for symbol names.
4582 * Changes in completion.
4584 Commands such as `shell', `run' and `set args', which pass arguments
4585 to inferior programs, now complete on file names, similar to what
4586 users expect at the shell prompt.
4588 Commands which accept locations, such as `disassemble', `print',
4589 `breakpoint', `until', etc. now complete on filenames as well as
4590 program symbols. Thus, if you type "break foob TAB", and the source
4591 files linked into the programs include `foobar.c', that file name will
4592 be one of the candidates for completion. However, file names are not
4593 considered for completion after you typed a colon that delimits a file
4594 name from a name of a function in that file, as in "break foo.c:bar".
4596 `set demangle-style' completes on available demangling styles.
4598 * New platform-independent commands:
4600 It is now possible to define a post-hook for a command as well as a
4601 hook that runs before the command. For more details, see the
4602 documentation of `hookpost' in the GDB manual.
4604 * Changes in GNU/Linux native debugging.
4606 Support for debugging multi-threaded programs has been completely
4607 revised for all platforms except m68k and sparc. You can now debug as
4608 many threads as your system allows you to have.
4610 Attach/detach is supported for multi-threaded programs.
4612 Support for SSE registers was added for x86. This doesn't work for
4613 multi-threaded programs though.
4615 * Changes in MIPS configurations.
4617 Multi-arch support is enabled for all MIPS configurations.
4619 GDB can now be built as native debugger on SGI Irix 6.x systems for
4620 debugging n32 executables. (Debugging 64-bit executables is not yet
4623 * Unified support for hardware watchpoints in all x86 configurations.
4625 Most (if not all) native x86 configurations support hardware-assisted
4626 breakpoints and watchpoints in a unified manner. This support
4627 implements debug register sharing between watchpoints, which allows to
4628 put a virtually infinite number of watchpoints on the same address,
4629 and also supports watching regions up to 16 bytes with several debug
4632 The new maintenance command `maintenance show-debug-regs' toggles
4633 debugging print-outs in functions that insert, remove, and test
4634 watchpoints and hardware breakpoints.
4636 * Changes in the DJGPP native configuration.
4638 New command ``info dos sysinfo'' displays assorted information about
4639 the CPU, OS, memory, and DPMI server.
4641 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4642 display information about segment descriptors stored in GDT, LDT, and
4645 New commands ``info dos pde'' and ``info dos pte'' display entries
4646 from Page Directory and Page Tables (for now works with CWSDPMI only).
4647 New command ``info dos address-pte'' displays the Page Table entry for
4648 a given linear address.
4650 GDB can now pass command lines longer than 126 characters to the
4651 program being debugged (requires an update to the libdbg.a library
4652 which is part of the DJGPP development kit).
4654 DWARF2 debug info is now supported.
4656 It is now possible to `step' and `next' through calls to `longjmp'.
4658 * Changes in documentation.
4660 All GDB documentation was converted to GFDL, the GNU Free
4661 Documentation License.
4663 Tracepoints-related commands are now fully documented in the GDB
4666 TUI, the Text-mode User Interface, is now documented in the manual.
4668 Tracepoints-related commands are now fully documented in the GDB
4671 The "GDB Internals" manual now has an index. It also includes
4672 documentation of `ui_out' functions, GDB coding standards, x86
4673 hardware watchpoints, and memory region attributes.
4675 * GDB's version number moved to ``version.in''
4677 The Makefile variable VERSION has been replaced by the file
4678 ``version.in''. People creating GDB distributions should update the
4679 contents of this file.
4683 GUD support is now a standard part of the EMACS distribution.
4685 *** Changes in GDB 5.0:
4687 * Improved support for debugging FP programs on x86 targets
4689 Unified and much-improved support for debugging floating-point
4690 programs on all x86 targets. In particular, ``info float'' now
4691 displays the FP registers in the same format on all x86 targets, with
4692 greater level of detail.
4694 * Improvements and bugfixes in hardware-assisted watchpoints
4696 It is now possible to watch array elements, struct members, and
4697 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4698 on x86 targets no longer erroneously trigger when the address is
4701 * Improvements in the native DJGPP version of GDB
4703 The distribution now includes all the scripts and auxiliary files
4704 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4705 machines ``out of the box''.
4707 The DJGPP version can now debug programs that use signals. It is
4708 possible to catch signals that happened in the debuggee, deliver
4709 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4710 would kill the program being debugged.) Programs that hook hardware
4711 interrupts (keyboard, timer, etc.) can also be debugged.
4713 It is now possible to debug DJGPP programs that redirect their
4714 standard handles or switch them to raw (as opposed to cooked) mode, or
4715 even close them. The command ``run < foo > bar'' works as expected,
4716 and ``info terminal'' reports useful information about the debuggee's
4717 terminal, including raw/cooked mode, redirection, etc.
4719 The DJGPP version now uses termios functions for console I/O, which
4720 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4723 DOS-style file names with drive letters are now fully supported by
4726 It is now possible to debug DJGPP programs that switch their working
4727 directory. It is also possible to rerun the debuggee any number of
4728 times without restarting GDB; thus, you can use the same setup,
4729 breakpoints, etc. for many debugging sessions.
4731 * New native configurations
4733 ARM GNU/Linux arm*-*-linux*
4734 PowerPC GNU/Linux powerpc-*-linux*
4738 Motorola MCore mcore-*-*
4739 x86 VxWorks i[3456]86-*-vxworks*
4740 PowerPC VxWorks powerpc-*-vxworks*
4741 TI TMS320C80 tic80-*-*
4743 * OBSOLETE configurations
4745 Altos 3068 m68*-altos-*
4746 Convex c1-*-*, c2-*-*
4748 ARM RISCix arm-*-* (as host)
4751 Configurations that have been declared obsolete will be commented out,
4752 but the code will be left in place. If there is no activity to revive
4753 these configurations before the next release of GDB, the sources will
4754 be permanently REMOVED.
4756 * Gould support removed
4758 Support for the Gould PowerNode and NP1 has been removed.
4760 * New features for SVR4
4762 On SVR4 native platforms (such as Solaris), if you attach to a process
4763 without first loading a symbol file, GDB will now attempt to locate and
4764 load symbols from the running process's executable file.
4766 * Many C++ enhancements
4768 C++ support has been greatly improved. Overload resolution now works properly
4769 in almost all cases. RTTI support is on the way.
4771 * Remote targets can connect to a sub-program
4773 A popen(3) style serial-device has been added. This device starts a
4774 sub-process (such as a stand-alone simulator) and then communicates
4775 with that. The sub-program to run is specified using the syntax
4776 ``|<program> <args>'' vis:
4778 (gdb) set remotedebug 1
4779 (gdb) target extended-remote |mn10300-elf-sim program-args
4781 * MIPS 64 remote protocol
4783 A long standing bug in the mips64 remote protocol where by GDB
4784 expected certain 32 bit registers (ex SR) to be transfered as 32
4785 instead of 64 bits has been fixed.
4787 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4788 added to provide backward compatibility with older versions of GDB.
4790 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4792 The command ``set remotebinarydownload'' command has been replaced by
4793 ``set remote X-packet''. Other commands in ``set remote'' family
4794 include ``set remote P-packet''.
4796 * Breakpoint commands accept ranges.
4798 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4799 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4800 ``tracepoint passcount'' also accepts a range of tracepoints.
4802 * ``apropos'' command added.
4804 The ``apropos'' command searches through command names and
4805 documentation strings, printing out matches, making it much easier to
4806 try to find a command that does what you are looking for.
4810 A new machine oriented interface (MI) has been added to GDB. This
4811 interface is designed for debug environments running GDB as a separate
4812 process. This is part of the long term libGDB project. See the
4813 "GDB/MI" chapter of the GDB manual for further information. It can be
4814 enabled by configuring with:
4816 .../configure --enable-gdbmi
4818 *** Changes in GDB-4.18:
4820 * New native configurations
4822 HP-UX 10.20 hppa*-*-hpux10.20
4823 HP-UX 11.x hppa*-*-hpux11.0*
4824 M68K GNU/Linux m68*-*-linux*
4828 Fujitsu FR30 fr30-*-elf*
4829 Intel StrongARM strongarm-*-*
4830 Mitsubishi D30V d30v-*-*
4832 * OBSOLETE configurations
4834 Gould PowerNode, NP1 np1-*-*, pn-*-*
4836 Configurations that have been declared obsolete will be commented out,
4837 but the code will be left in place. If there is no activity to revive
4838 these configurations before the next release of GDB, the sources will
4839 be permanently REMOVED.
4843 As a compatibility experiment, GDB's source files buildsym.h and
4844 buildsym.c have been converted to pure standard C, no longer
4845 containing any K&R compatibility code. We believe that all systems in
4846 use today either come with a standard C compiler, or have a GCC port
4847 available. If this is not true, please report the affected
4848 configuration to bug-gdb@gnu.org immediately. See the README file for
4849 information about getting a standard C compiler if you don't have one
4854 GDB now uses readline 2.2.
4856 * set extension-language
4858 You can now control the mapping between filename extensions and source
4859 languages by using the `set extension-language' command. For instance,
4860 you can ask GDB to treat .c files as C++ by saying
4861 set extension-language .c c++
4862 The command `info extensions' lists all of the recognized extensions
4863 and their associated languages.
4865 * Setting processor type for PowerPC and RS/6000
4867 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4868 you can use the `set processor' command to specify what variant of the
4869 PowerPC family you are debugging. The command
4873 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4874 following PowerPC and RS6000 variants:
4876 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4877 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4879 403GC IBM PowerPC 403GC
4880 505 Motorola PowerPC 505
4881 860 Motorola PowerPC 860 or 850
4882 601 Motorola PowerPC 601
4883 602 Motorola PowerPC 602
4884 603 Motorola/IBM PowerPC 603 or 603e
4885 604 Motorola PowerPC 604 or 604e
4886 750 Motorola/IBM PowerPC 750 or 750
4888 At the moment, this command just tells GDB what to name the
4889 special-purpose processor registers. Since almost all the affected
4890 registers are inaccessible to user-level programs, this command is
4891 only useful for remote debugging in its present form.
4895 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4896 more extensive support for HP-UX. Added features include shared
4897 library support, kernel threads and hardware watchpoints for 11.00,
4898 support for HP's ANSI C and C++ compilers, and a compatibility mode
4899 for xdb and dbx commands.
4903 HP's donation includes the new concept of catchpoints, which is a
4904 generalization of the old catch command. On HP-UX, it is now possible
4905 to catch exec, fork, and vfork, as well as library loading.
4907 This means that the existing catch command has changed; its first
4908 argument now specifies the type of catch to be set up. See the
4909 output of "help catch" for a list of catchpoint types.
4911 * Debugging across forks
4913 On HP-UX, you can choose which process to debug when a fork() happens
4918 HP has donated a curses-based terminal user interface (TUI). To get
4919 it, build with --enable-tui. Although this can be enabled for any
4920 configuration, at present it only works for native HP debugging.
4922 * GDB remote protocol additions
4924 A new protocol packet 'X' that writes binary data is now available.
4925 Default behavior is to try 'X', then drop back to 'M' if the stub
4926 fails to respond. The settable variable `remotebinarydownload'
4927 allows explicit control over the use of 'X'.
4929 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4930 full 64-bit address. The command
4932 set remoteaddresssize 32
4934 can be used to revert to the old behaviour. For existing remote stubs
4935 the change should not be noticed, as the additional address information
4938 In order to assist in debugging stubs, you may use the maintenance
4939 command `packet' to send any text string to the stub. For instance,
4941 maint packet heythere
4943 sends the packet "$heythere#<checksum>". Note that it is very easy to
4944 disrupt a debugging session by sending the wrong packet at the wrong
4947 The compare-sections command allows you to compare section data on the
4948 target to what is in the executable file without uploading or
4949 downloading, by comparing CRC checksums.
4951 * Tracing can collect general expressions
4953 You may now collect general expressions at tracepoints. This requires
4954 further additions to the target-side stub; see tracepoint.c and
4955 doc/agentexpr.texi for further details.
4957 * mask-address variable for Mips
4959 For Mips targets, you may control the zeroing of the upper 32 bits of
4960 a 64-bit address by entering `set mask-address on'. This is mainly
4961 of interest to users of embedded R4xxx and R5xxx processors.
4963 * Higher serial baud rates
4965 GDB's serial code now allows you to specify baud rates 57600, 115200,
4966 230400, and 460800 baud. (Note that your host system may not be able
4967 to achieve all of these rates.)
4971 The i960 configuration now includes an initial implementation of a
4972 builtin simulator, contributed by Jim Wilson.
4975 *** Changes in GDB-4.17:
4977 * New native configurations
4979 Alpha GNU/Linux alpha*-*-linux*
4980 Unixware 2.x i[3456]86-unixware2*
4981 Irix 6.x mips*-sgi-irix6*
4982 PowerPC GNU/Linux powerpc-*-linux*
4983 PowerPC Solaris powerpcle-*-solaris*
4984 Sparc GNU/Linux sparc-*-linux*
4985 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4989 Argonaut Risc Chip (ARC) arc-*-*
4990 Hitachi H8/300S h8300*-*-*
4991 Matsushita MN10200 w/simulator mn10200-*-*
4992 Matsushita MN10300 w/simulator mn10300-*-*
4993 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4994 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4995 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4996 Mitsubishi D10V w/simulator d10v-*-*
4997 Mitsubishi M32R/D w/simulator m32r-*-elf*
4998 Tsqware Sparclet sparclet-*-*
4999 NEC V850 w/simulator v850-*-*
5001 * New debugging protocols
5003 ARM with RDI protocol arm*-*-*
5004 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5005 DDB and LSI variants of PMON protocol mips*-*-*
5006 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5007 PowerPC with SDS protocol powerpc{,le}-*-eabi
5008 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5012 All configurations can now understand and use the DWARF 2 debugging
5013 format. The choice is automatic, if the symbol file contains DWARF 2
5018 GDB now includes basic Java language support. This support is
5019 only useful with Java compilers that produce native machine code.
5021 * solib-absolute-prefix and solib-search-path
5023 For SunOS and SVR4 shared libraries, you may now set the prefix for
5024 loading absolute shared library symbol files, and the search path for
5025 locating non-absolute shared library symbol files.
5027 * Live range splitting
5029 GDB can now effectively debug code for which GCC has performed live
5030 range splitting as part of its optimization. See gdb/doc/LRS for
5031 more details on the expected format of the stabs information.
5035 GDB's support for the GNU Hurd, including thread debugging, has been
5036 updated to work with current versions of the Hurd.
5040 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5041 instruction set. ARM GDB automatically detects when Thumb
5042 instructions are in use, and adjusts disassembly and backtracing
5047 GDB's MIPS target configurations now handle the MIP16 16-bit
5052 GDB now includes support for overlays; if an executable has been
5053 linked such that multiple sections are based at the same address, GDB
5054 will decide which section to use for symbolic info. You can choose to
5055 control the decision manually, using overlay commands, or implement
5056 additional target-side support and use "overlay load-target" to bring
5057 in the overlay mapping. Do "help overlay" for more detail.
5061 The command "info symbol <address>" displays information about
5062 the symbol at the specified address.
5066 The standard remote protocol now includes an extension that allows
5067 asynchronous collection and display of trace data. This requires
5068 extensive support in the target-side debugging stub. Tracing mode
5069 includes a new interaction mode in GDB and new commands: see the
5070 file tracepoint.c for more details.
5074 Configurations for embedded MIPS now include a simulator contributed
5075 by Cygnus Solutions. The simulator supports the instruction sets
5076 of most MIPS variants.
5080 Sparc configurations may now include the ERC32 simulator contributed
5081 by the European Space Agency. The simulator is not built into
5082 Sparc targets by default; configure with --enable-sim to include it.
5086 For target configurations that may include multiple variants of a
5087 basic architecture (such as MIPS and SH), you may now set the
5088 architecture explicitly. "set arch" sets, "info arch" lists
5089 the possible architectures.
5091 *** Changes in GDB-4.16:
5093 * New native configurations
5095 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5096 M68K NetBSD m68k-*-netbsd*
5097 PowerPC AIX 4.x powerpc-*-aix*
5098 PowerPC MacOS powerpc-*-macos*
5099 PowerPC Windows NT powerpcle-*-cygwin32
5100 RS/6000 AIX 4.x rs6000-*-aix4*
5104 ARM with RDP protocol arm-*-*
5105 I960 with MON960 i960-*-coff
5106 MIPS VxWorks mips*-*-vxworks*
5107 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5108 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5110 Matra Sparclet sparclet-*-*
5114 The powerpc-eabi configuration now includes the PSIM simulator,
5115 contributed by Andrew Cagney, with assistance from Mike Meissner.
5116 PSIM is a very elaborate model of the PowerPC, including not only
5117 basic instruction set execution, but also details of execution unit
5118 performance and I/O hardware. See sim/ppc/README for more details.
5122 GDB now works with Solaris 2.5.
5124 * Windows 95/NT native
5126 GDB will now work as a native debugger on Windows 95 and Windows NT.
5127 To build it from source, you must use the "gnu-win32" environment,
5128 which uses a DLL to emulate enough of Unix to run the GNU tools.
5129 Further information, binaries, and sources are available at
5130 ftp.cygnus.com, under pub/gnu-win32.
5132 * dont-repeat command
5134 If a user-defined command includes the command `dont-repeat', then the
5135 command will not be repeated if the user just types return. This is
5136 useful if the command is time-consuming to run, so that accidental
5137 extra keystrokes don't run the same command many times.
5139 * Send break instead of ^C
5141 The standard remote protocol now includes an option to send a break
5142 rather than a ^C to the target in order to interrupt it. By default,
5143 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5145 * Remote protocol timeout
5147 The standard remote protocol includes a new variable `remotetimeout'
5148 that allows you to set the number of seconds before GDB gives up trying
5149 to read from the target. The default value is 2.
5151 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5153 By default GDB will automatically keep track of objects as they are
5154 loaded and unloaded by the dynamic linker. By using the command `set
5155 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5156 when shared library events occur, thus allowing you to set breakpoints
5157 in shared libraries which are explicitly loaded by the inferior.
5159 Note this feature does not work on hpux8. On hpux9 you must link
5160 /usr/lib/end.o into your program. This feature should work
5161 automatically on hpux10.
5163 * Irix 5.x hardware watchpoint support
5165 Irix 5 configurations now support the use of hardware watchpoints.
5167 * Mips protocol "SYN garbage limit"
5169 When debugging a Mips target using the `target mips' protocol, you
5170 may set the number of characters that GDB will ignore by setting
5171 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5172 every character. The default value is 1050.
5174 * Recording and replaying remote debug sessions
5176 If you set `remotelogfile' to the name of a file, gdb will write to it
5177 a recording of a remote debug session. This recording may then be
5178 replayed back to gdb using "gdbreplay". See gdbserver/README for
5179 details. This is useful when you have a problem with GDB while doing
5180 remote debugging; you can make a recording of the session and send it
5181 to someone else, who can then recreate the problem.
5183 * Speedups for remote debugging
5185 GDB includes speedups for downloading and stepping MIPS systems using
5186 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5187 and more efficient S-record downloading.
5189 * Memory use reductions and statistics collection
5191 GDB now uses less memory and reports statistics about memory usage.
5192 Try the `maint print statistics' command, for example.
5194 *** Changes in GDB-4.15:
5196 * Psymtabs for XCOFF
5198 The symbol reader for AIX GDB now uses partial symbol tables. This
5199 can greatly improve startup time, especially for large executables.
5201 * Remote targets use caching
5203 Remote targets now use a data cache to speed up communication with the
5204 remote side. The data cache could lead to incorrect results because
5205 it doesn't know about volatile variables, thus making it impossible to
5206 debug targets which use memory mapped I/O devices. `set remotecache
5207 off' turns the the data cache off.
5209 * Remote targets may have threads
5211 The standard remote protocol now includes support for multiple threads
5212 in the target system, using new protocol commands 'H' and 'T'. See
5213 gdb/remote.c for details.
5217 If GDB is configured with `--enable-netrom', then it will include
5218 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5219 acts as though it is a bank of ROM on the target board, but you can
5220 write into it over the network. GDB's support consists only of
5221 support for fast loading into the emulated ROM; to debug, you must use
5222 another protocol, such as standard remote protocol. The usual
5223 sequence is something like
5225 target nrom <netrom-hostname>
5227 target remote <netrom-hostname>:1235
5231 GDB now includes support for the Apple Macintosh, as a host only. It
5232 may be run as either an MPW tool or as a standalone application, and
5233 it can debug through the serial port. All the usual GDB commands are
5234 available, but to the target command, you must supply "serial" as the
5235 device type instead of "/dev/ttyXX". See mpw-README in the main
5236 directory for more information on how to build. The MPW configuration
5237 scripts */mpw-config.in support only a few targets, and only the
5238 mips-idt-ecoff target has been tested.
5242 GDB configuration now uses autoconf. This is not user-visible,
5243 but does simplify configuration and building.
5247 GDB now supports hpux10.
5249 *** Changes in GDB-4.14:
5251 * New native configurations
5253 x86 FreeBSD i[345]86-*-freebsd
5254 x86 NetBSD i[345]86-*-netbsd
5255 NS32k NetBSD ns32k-*-netbsd
5256 Sparc NetBSD sparc-*-netbsd
5260 A29K VxWorks a29k-*-vxworks
5261 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5262 CPU32 EST-300 emulator m68*-*-est*
5263 PowerPC ELF powerpc-*-elf
5266 * Alpha OSF/1 support for procfs
5268 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5269 possible to attach to running processes. As the mounting of the /proc
5270 filesystem is optional on the Alpha, GDB automatically determines
5271 the availability of /proc during startup. This can lead to problems
5272 if /proc is unmounted after GDB has been started.
5274 * Arguments to user-defined commands
5276 User commands may accept up to 10 arguments separated by whitespace.
5277 Arguments are accessed within the user command via $arg0..$arg9. A
5280 print $arg0 + $arg1 + $arg2
5282 To execute the command use:
5285 Defines the command "adder" which prints the sum of its three arguments.
5286 Note the arguments are text substitutions, so they may reference variables,
5287 use complex expressions, or even perform inferior function calls.
5289 * New `if' and `while' commands
5291 This makes it possible to write more sophisticated user-defined
5292 commands. Both commands take a single argument, which is the
5293 expression to evaluate, and must be followed by the commands to
5294 execute, one per line, if the expression is nonzero, the list being
5295 terminated by the word `end'. The `if' command list may include an
5296 `else' word, which causes the following commands to be executed only
5297 if the expression is zero.
5299 * Fortran source language mode
5301 GDB now includes partial support for Fortran 77. It will recognize
5302 Fortran programs and can evaluate a subset of Fortran expressions, but
5303 variables and functions may not be handled correctly. GDB will work
5304 with G77, but does not yet know much about symbols emitted by other
5307 * Better HPUX support
5309 Most debugging facilities now work on dynamic executables for HPPAs
5310 running hpux9 or later. You can attach to running dynamically linked
5311 processes, but by default the dynamic libraries will be read-only, so
5312 for instance you won't be able to put breakpoints in them. To change
5313 that behavior do the following before running the program:
5319 This will cause the libraries to be mapped private and read-write.
5320 To revert to the normal behavior, do this:
5326 You cannot set breakpoints or examine data in the library until after
5327 the library is loaded if the function/data symbols do not have
5330 GDB can now also read debug symbols produced by the HP C compiler on
5331 HPPAs (sorry, no C++, Fortran or 68k support).
5333 * Target byte order now dynamically selectable
5335 You can choose which byte order to use with a target system, via the
5336 commands "set endian big" and "set endian little", and you can see the
5337 current setting by using "show endian". You can also give the command
5338 "set endian auto", in which case GDB will use the byte order
5339 associated with the executable. Currently, only embedded MIPS
5340 configurations support dynamic selection of target byte order.
5342 * New DOS host serial code
5344 This version uses DPMI interrupts to handle buffered I/O, so you
5345 no longer need to run asynctsr when debugging boards connected to
5348 *** Changes in GDB-4.13:
5350 * New "complete" command
5352 This lists all the possible completions for the rest of the line, if it
5353 were to be given as a command itself. This is intended for use by emacs.
5355 * Trailing space optional in prompt
5357 "set prompt" no longer adds a space for you after the prompt you set. This
5358 allows you to set a prompt which ends in a space or one that does not.
5360 * Breakpoint hit counts
5362 "info break" now displays a count of the number of times the breakpoint
5363 has been hit. This is especially useful in conjunction with "ignore"; you
5364 can ignore a large number of breakpoint hits, look at the breakpoint info
5365 to see how many times the breakpoint was hit, then run again, ignoring one
5366 less than that number, and this will get you quickly to the last hit of
5369 * Ability to stop printing at NULL character
5371 "set print null-stop" will cause GDB to stop printing the characters of
5372 an array when the first NULL is encountered. This is useful when large
5373 arrays actually contain only short strings.
5375 * Shared library breakpoints
5377 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5378 breakpoints in shared libraries before the executable is run.
5380 * Hardware watchpoints
5382 There is a new hardware breakpoint for the watch command for sparclite
5383 targets. See gdb/sparclite/hw_breakpoint.note.
5385 Hardware watchpoints are also now supported under GNU/Linux.
5389 Annotations have been added. These are for use with graphical interfaces,
5390 and are still experimental. Currently only gdba.el uses these.
5392 * Improved Irix 5 support
5394 GDB now works properly with Irix 5.2.
5396 * Improved HPPA support
5398 GDB now works properly with the latest GCC and GAS.
5400 * New native configurations
5402 Sequent PTX4 i[34]86-sequent-ptx4
5403 HPPA running OSF/1 hppa*-*-osf*
5404 Atari TT running SVR4 m68*-*-sysv4*
5405 RS/6000 LynxOS rs6000-*-lynxos*
5409 OS/9000 i[34]86-*-os9k
5410 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5413 * Hitachi SH7000 and E7000-PC ICE support
5415 There is now support for communicating with the Hitachi E7000-PC ICE.
5416 This is available automatically when GDB is configured for the SH.
5420 As usual, a variety of small fixes and improvements, both generic
5421 and configuration-specific. See the ChangeLog for more detail.
5423 *** Changes in GDB-4.12:
5425 * Irix 5 is now supported
5429 GDB-4.12 on the HPPA has a number of changes which make it unable
5430 to debug the output from the currently released versions of GCC and
5431 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5432 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5433 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5436 *** Changes in GDB-4.11:
5438 * User visible changes:
5442 The "set remotedebug" option is now consistent between the mips remote
5443 target, remote targets using the gdb-specific protocol, UDI (AMD's
5444 debug protocol for the 29k) and the 88k bug monitor. It is now an
5445 integer specifying a debug level (normally 0 or 1, but 2 means more
5446 debugging info for the mips target).
5448 * DEC Alpha native support
5450 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5451 debug info, but GDB works fairly well with the DEC compiler and should
5452 work with a future GCC release. See the README file for a few
5453 Alpha-specific notes.
5455 * Preliminary thread implementation
5457 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5459 * LynxOS native and target support for 386
5461 This release has been hosted on LynxOS 2.2, and also can be configured
5462 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5465 * Improvements in C++ mangling/demangling.
5467 This release has much better g++ debugging, specifically in name
5468 mangling/demangling, virtual function calls, print virtual table,
5469 call methods, ...etc.
5471 *** Changes in GDB-4.10:
5473 * User visible changes:
5475 Remote debugging using the GDB-specific (`target remote') protocol now
5476 supports the `load' command. This is only useful if you have some
5477 other way of getting the stub to the target system, and you can put it
5478 somewhere in memory where it won't get clobbered by the download.
5480 Filename completion now works.
5482 When run under emacs mode, the "info line" command now causes the
5483 arrow to point to the line specified. Also, "info line" prints
5484 addresses in symbolic form (as well as hex).
5486 All vxworks based targets now support a user settable option, called
5487 vxworks-timeout. This option represents the number of seconds gdb
5488 should wait for responses to rpc's. You might want to use this if
5489 your vxworks target is, perhaps, a slow software simulator or happens
5490 to be on the far side of a thin network line.
5494 This release contains support for using a DEC alpha as a GDB host for
5495 cross debugging. Native alpha debugging is not supported yet.
5498 *** Changes in GDB-4.9:
5502 This is the first GDB release which is accompanied by a matching testsuite.
5503 The testsuite requires installation of dejagnu, which should be available
5504 via ftp from most sites that carry GNU software.
5508 'Cfront' style demangling has had its name changed to 'ARM' style, to
5509 emphasize that it was written from the specifications in the C++ Annotated
5510 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5511 disclaimers, it still generated too much confusion with users attempting to
5512 use gdb with AT&T cfront.
5516 GDB now uses a standard remote interface to a simulator library.
5517 So far, the library contains simulators for the Zilog Z8001/2, the
5518 Hitachi H8/300, H8/500 and Super-H.
5520 * New targets supported
5522 H8/300 simulator h8300-hitachi-hms or h8300hms
5523 H8/500 simulator h8500-hitachi-hms or h8500hms
5524 SH simulator sh-hitachi-hms or sh
5525 Z8000 simulator z8k-zilog-none or z8ksim
5526 IDT MIPS board over serial line mips-idt-ecoff
5528 Cross-debugging to GO32 targets is supported. It requires a custom
5529 version of the i386-stub.c module which is integrated with the
5530 GO32 memory extender.
5532 * New remote protocols
5534 MIPS remote debugging protocol.
5536 * New source languages supported
5538 This version includes preliminary support for Chill, a Pascal like language
5539 used by telecommunications companies. Chill support is also being integrated
5540 into the GNU compiler, but we don't know when it will be publically available.
5543 *** Changes in GDB-4.8:
5545 * HP Precision Architecture supported
5547 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5548 version of this support was available as a set of patches from the
5549 University of Utah. GDB does not support debugging of programs
5550 compiled with the HP compiler, because HP will not document their file
5551 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5552 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5554 Many problems in the preliminary version have been fixed.
5556 * Faster and better demangling
5558 We have improved template demangling and fixed numerous bugs in the GNU style
5559 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5560 character types (wchar_t) are now supported. Demangling of each symbol is now
5561 only done once, and is cached when the symbol table for a file is read in.
5562 This results in a small increase in memory usage for C programs, a moderate
5563 increase in memory usage for C++ programs, and a fantastic speedup in
5566 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5567 from the specifications in the Annotated Reference Manual, which AT&T's
5568 compiler does not actually implement.
5570 * G++ multiple inheritance compiler problem
5572 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5573 inheritance lattices was reworked to properly discover ambiguities. We
5574 recently found an example which causes this new algorithm to fail in a
5575 very subtle way, producing bad debug information for those classes.
5576 The file 'gcc.patch' (in this directory) can be applied to gcc to
5577 circumvent the problem. A future GCC release will contain a complete
5580 The previous G++ debug info problem (mentioned below for the gdb-4.7
5581 release) is fixed in gcc version 2.3.2.
5583 * Improved configure script
5585 The `configure' script will now attempt to guess your system type if
5586 you don't supply a host system type. The old scheme of supplying a
5587 host system triplet is preferable over using this. All the magic is
5588 done in the new `config.guess' script. Examine it for details.
5590 We have also brought our configure script much more in line with the FSF's
5591 version. It now supports the --with-xxx options. In particular,
5592 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5593 The resulting GDB will not be able to read arbitrary object file formats --
5594 only the format ``expected'' to be used on the configured target system.
5595 We hope to make this the default in a future release.
5597 * Documentation improvements
5599 There's new internal documentation on how to modify GDB, and how to
5600 produce clean changes to the code. We implore people to read it
5601 before submitting changes.
5603 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5604 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5605 `info' files are also provided. To build `info' files from scratch,
5606 you will need the latest `makeinfo' release, which will be available in
5607 a future texinfo-X.Y release.
5609 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5610 We're not sure exactly which versions have this problem, but it has
5611 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5612 or better. If that isn't possible, there is a patch in
5613 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5614 around this problem.
5618 GDB now supports array constants that can be used in expressions typed in by
5619 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5620 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5623 The new directory `gdb/sparclite' contains a program that demonstrates
5624 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5626 * New native hosts supported
5628 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5629 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5631 * New targets supported
5633 AMD 29k family via UDI a29k-amd-udi or udi29k
5635 * New file formats supported
5637 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5638 HPUX core files, and SCO 3.2v2 core files.
5642 Attaching to processes now works again; thanks for the many bug reports.
5644 We have also stomped on a bunch of core dumps caused by
5645 printf_filtered("%s") problems.
5647 We eliminated a copyright problem on the rpc and ptrace header files
5648 for VxWorks, which was discovered at the last minute during the 4.7
5649 release. You should now be able to build a VxWorks GDB.
5651 You can now interrupt gdb while an attached process is running. This
5652 will cause the attached process to stop, and give control back to GDB.
5654 We fixed problems caused by using too many file descriptors
5655 for reading symbols from object files and libraries. This was
5656 especially a problem for programs that used many (~100) shared
5659 The `step' command now only enters a subroutine if there is line number
5660 information for the subroutine. Otherwise it acts like the `next'
5661 command. Previously, `step' would enter subroutines if there was
5662 any debugging information about the routine. This avoids problems
5663 when using `cc -g1' on MIPS machines.
5665 * Internal improvements
5667 GDB's internal interfaces have been improved to make it easier to support
5668 debugging of multiple languages in the future.
5670 GDB now uses a common structure for symbol information internally.
5671 Minimal symbols (derived from linkage symbols in object files), partial
5672 symbols (from a quick scan of debug information), and full symbols
5673 contain a common subset of information, making it easier to write
5674 shared code that handles any of them.
5676 * New command line options
5678 We now accept --silent as an alias for --quiet.
5682 The memory-mapped-malloc library is now licensed under the GNU Library
5683 General Public License.
5685 *** Changes in GDB-4.7:
5687 * Host/native/target split
5689 GDB has had some major internal surgery to untangle the support for
5690 hosts and remote targets. Now, when you configure GDB for a remote
5691 target, it will no longer load in all of the support for debugging
5692 local programs on the host. When fully completed and tested, this will
5693 ensure that arbitrary host/target combinations are possible.
5695 The primary conceptual shift is to separate the non-portable code in
5696 GDB into three categories. Host specific code is required any time GDB
5697 is compiled on that host, regardless of the target. Target specific
5698 code relates to the peculiarities of the target, but can be compiled on
5699 any host. Native specific code is everything else: it can only be
5700 built when the host and target are the same system. Child process
5701 handling and core file support are two common `native' examples.
5703 GDB's use of /proc for controlling Unix child processes is now cleaner.
5704 It has been split out into a single module under the `target_ops' vector,
5705 plus two native-dependent functions for each system that uses /proc.
5707 * New hosts supported
5709 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5710 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5711 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5713 * New targets supported
5715 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5716 68030 and CPU32 m68030-*-*, m68332-*-*
5718 * New native hosts supported
5720 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5721 (386bsd is not well tested yet)
5722 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5724 * New file formats supported
5726 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5727 supports reading of `a.out.adobe' object files, which are an a.out
5728 format extended with minimal information about multiple sections.
5732 `show copying' is the same as the old `info copying'.
5733 `show warranty' is the same as `info warrantee'.
5734 These were renamed for consistency. The old commands continue to work.
5736 `info handle' is a new alias for `info signals'.
5738 You can now define pre-command hooks, which attach arbitrary command
5739 scripts to any command. The commands in the hook will be executed
5740 prior to the user's command. You can also create a hook which will be
5741 executed whenever the program stops. See gdb.texinfo.
5745 We now deal with Cfront style name mangling, and can even extract type
5746 info from mangled symbols. GDB can automatically figure out which
5747 symbol mangling style your C++ compiler uses.
5749 Calling of methods and virtual functions has been improved as well.
5753 The crash that occured when debugging Sun Ansi-C compiled binaries is
5754 fixed. This was due to mishandling of the extra N_SO stabs output
5757 We also finally got Ultrix 4.2 running in house, and fixed core file
5758 support, with help from a dozen people on the net.
5760 John M. Farrell discovered that the reason that single-stepping was so
5761 slow on all of the Mips based platforms (primarily SGI and DEC) was
5762 that we were trying to demangle and lookup a symbol used for internal
5763 purposes on every instruction that was being stepped through. Changing
5764 the name of that symbol so that it couldn't be mistaken for a C++
5765 mangled symbol sped things up a great deal.
5767 Rich Pixley sped up symbol lookups in general by getting much smarter
5768 about when C++ symbol mangling is necessary. This should make symbol
5769 completion (TAB on the command line) much faster. It's not as fast as
5770 we'd like, but it's significantly faster than gdb-4.6.
5774 A new user controllable variable 'call_scratch_address' can
5775 specify the location of a scratch area to be used when GDB
5776 calls a function in the target. This is necessary because the
5777 usual method of putting the scratch area on the stack does not work
5778 in systems that have separate instruction and data spaces.
5780 We integrated changes to support the 29k UDI (Universal Debugger
5781 Interface), but discovered at the last minute that we didn't have all
5782 of the appropriate copyright paperwork. We are working with AMD to
5783 resolve this, and hope to have it available soon.
5787 We have sped up the remote serial line protocol, especially for targets
5788 with lots of registers. It now supports a new `expedited status' ('T')
5789 message which can be used in place of the existing 'S' status message.
5790 This allows the remote stub to send only the registers that GDB
5791 needs to make a quick decision about single-stepping or conditional
5792 breakpoints, eliminating the need to fetch the entire register set for
5793 each instruction being stepped through.
5795 The GDB remote serial protocol now implements a write-through cache for
5796 registers, only re-reading the registers if the target has run.
5798 There is also a new remote serial stub for SPARC processors. You can
5799 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5800 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5801 processor with a serial port.
5805 Configure.in files have become much easier to read and modify. A new
5806 `table driven' format makes it more obvious what configurations are
5807 supported, and what files each one uses.
5811 There is a new opcodes library which will eventually contain all of the
5812 disassembly routines and opcode tables. At present, it only contains
5813 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5814 disassembler (binutils/objdump) to share these routines.
5816 The libiberty library is now copylefted under the GNU Library General
5817 Public License. This allows more liberal use, and was done so libg++
5818 can use it. This makes no difference to GDB, since the Library License
5819 grants all the rights from the General Public License.
5823 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5824 reference to the stabs symbol info used by the debugger. It is (as far
5825 as we know) the only published document on this fascinating topic. We
5826 encourage you to read it, compare it to the stabs information on your
5827 system, and send improvements on the document in general (to
5828 bug-gdb@prep.ai.mit.edu).
5830 And, of course, many bugs have been fixed.
5833 *** Changes in GDB-4.6:
5835 * Better support for C++ function names
5837 GDB now accepts as input the "demangled form" of C++ overloaded function
5838 names and member function names, and can do command completion on such names
5839 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5840 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5841 Make use of command completion, it is your friend.
5843 GDB also now accepts a variety of C++ mangled symbol formats. They are
5844 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5845 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5846 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5847 for the list of formats.
5849 * G++ symbol mangling problem
5851 Recent versions of gcc have a bug in how they emit debugging information for
5852 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5853 directory) can be applied to gcc to fix the problem. Alternatively, if you
5854 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5855 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5856 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5859 * New 'maintenance' command
5861 All of the commands related to hacking GDB internals have been moved out of
5862 the main command set, and now live behind the 'maintenance' command. This
5863 can also be abbreviated as 'mt'. The following changes were made:
5865 dump-me -> maintenance dump-me
5866 info all-breakpoints -> maintenance info breakpoints
5867 printmsyms -> maintenance print msyms
5868 printobjfiles -> maintenance print objfiles
5869 printpsyms -> maintenance print psymbols
5870 printsyms -> maintenance print symbols
5872 The following commands are new:
5874 maintenance demangle Call internal GDB demangler routine to
5875 demangle a C++ link name and prints the result.
5876 maintenance print type Print a type chain for a given symbol
5878 * Change to .gdbinit file processing
5880 We now read the $HOME/.gdbinit file before processing the argv arguments
5881 (e.g. reading symbol files or core files). This allows global parameters to
5882 be set, which will apply during the symbol reading. The ./.gdbinit is still
5883 read after argv processing.
5885 * New hosts supported
5887 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5889 GNU/Linux support i386-unknown-linux or linux
5891 We are also including code to support the HP/PA running BSD and HPUX. This
5892 is almost guaranteed not to work, as we didn't have time to test or build it
5893 for this release. We are including it so that the more adventurous (or
5894 masochistic) of you can play with it. We also had major problems with the
5895 fact that the compiler that we got from HP doesn't support the -g option.
5898 * New targets supported
5900 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5902 * More smarts about finding #include files
5904 GDB now remembers the compilation directory for all include files, and for
5905 all files from which C is generated (like yacc and lex sources). This
5906 greatly improves GDB's ability to find yacc/lex sources, and include files,
5907 especially if you are debugging your program from a directory different from
5908 the one that contains your sources.
5910 We also fixed a bug which caused difficulty with listing and setting
5911 breakpoints in include files which contain C code. (In the past, you had to
5912 try twice in order to list an include file that you hadn't looked at before.)
5914 * Interesting infernals change
5916 GDB now deals with arbitrary numbers of sections, where the symbols for each
5917 section must be relocated relative to that section's landing place in the
5918 target's address space. This work was needed to support ELF with embedded
5919 stabs used by Solaris-2.0.
5921 * Bug fixes (of course!)
5923 There have been loads of fixes for the following things:
5924 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5925 i960, stabs, DOS(GO32), procfs, etc...
5927 See the ChangeLog for details.
5929 *** Changes in GDB-4.5:
5931 * New machines supported (host and target)
5933 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5935 SGI Irix-4.x mips-sgi-irix4 or iris4
5937 * New malloc package
5939 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5940 Mmalloc is capable of handling mutiple heaps of memory. It is also
5941 capable of saving a heap to a file, and then mapping it back in later.
5942 This can be used to greatly speedup the startup of GDB by using a
5943 pre-parsed symbol table which lives in a mmalloc managed heap. For
5944 more details, please read mmalloc/mmalloc.texi.
5948 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5949 'help info proc' for details.
5951 * MIPS ecoff symbol table format
5953 The code that reads MIPS symbol table format is now supported on all hosts.
5954 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5957 * File name changes for MS-DOS
5959 Many files in the config directories have been renamed to make it easier to
5960 support GDB on MS-DOSe systems (which have very restrictive file name
5961 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5962 environment) is close to working but has some remaining problems. Note
5963 that debugging of DOS programs is not supported, due to limitations
5964 in the ``operating system'', but it can be used to host cross-debugging.
5966 * Cross byte order fixes
5968 Many fixes have been made to support cross debugging of Sparc and MIPS
5969 targets from hosts whose byte order differs.
5971 * New -mapped and -readnow options
5973 If memory-mapped files are available on your system through the 'mmap'
5974 system call, you can use the -mapped option on the `file' or
5975 `symbol-file' commands to cause GDB to write the symbols from your
5976 program into a reusable file. If the program you are debugging is
5977 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5978 Future GDB debugging sessions will notice the presence of this file,
5979 and will quickly map in symbol information from it, rather than reading
5980 the symbol table from the executable program. Using the '-mapped'
5981 option in a GDB `file' or `symbol-file' command has the same effect as
5982 starting GDB with the '-mapped' command-line option.
5984 You can cause GDB to read the entire symbol table immediately by using
5985 the '-readnow' option with any of the commands that load symbol table
5986 information (or on the GDB command line). This makes the command
5987 slower, but makes future operations faster.
5989 The -mapped and -readnow options are typically combined in order to
5990 build a `fred.syms' file that contains complete symbol information.
5991 A simple GDB invocation to do nothing but build a `.syms' file for future
5994 gdb -batch -nx -mapped -readnow programname
5996 The `.syms' file is specific to the host machine on which GDB is run.
5997 It holds an exact image of GDB's internal symbol table. It cannot be
5998 shared across multiple host platforms.
6000 * longjmp() handling
6002 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6003 siglongjmp() without losing control. This feature has not yet been ported to
6004 all systems. It currently works on many 386 platforms, all MIPS-based
6005 platforms (SGI, DECstation, etc), and Sun3/4.
6009 Preliminary work has been put in to support the new Solaris OS from Sun. At
6010 this time, it can control and debug processes, but it is not capable of
6015 As always, many many bug fixes. The major areas were with g++, and mipsread.
6016 People using the MIPS-based platforms should experience fewer mysterious
6017 crashes and trashed symbol tables.
6019 *** Changes in GDB-4.4:
6021 * New machines supported (host and target)
6023 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6025 BSD Reno on Vax vax-dec-bsd
6026 Ultrix on Vax vax-dec-ultrix
6028 * New machines supported (target)
6030 AMD 29000 embedded, using EBMON a29k-none-none
6034 GDB continues to improve its handling of C++. `References' work better.
6035 The demangler has also been improved, and now deals with symbols mangled as
6036 per the Annotated C++ Reference Guide.
6038 GDB also now handles `stabs' symbol information embedded in MIPS
6039 `ecoff' symbol tables. Since the ecoff format was not easily
6040 extensible to handle new languages such as C++, this appeared to be a
6041 good way to put C++ debugging info into MIPS binaries. This option
6042 will be supported in the GNU C compiler, version 2, when it is
6045 * New features for SVR4
6047 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6048 shared libraries. Debugging dynamically linked programs should present
6049 only minor differences from debugging statically linked programs.
6051 The `info proc' command will print out information about any process
6052 on an SVR4 system (including the one you are debugging). At the moment,
6053 it prints the address mappings of the process.
6055 If you bring up GDB on another SVR4 system, please send mail to
6056 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6058 * Better dynamic linking support in SunOS
6060 Reading symbols from shared libraries which contain debugging symbols
6061 now works properly. However, there remain issues such as automatic
6062 skipping of `transfer vector' code during function calls, which
6063 make it harder to debug code in a shared library, than to debug the
6064 same code linked statically.
6068 GDB is now using the latest `getopt' routines from the FSF. This
6069 version accepts the -- prefix for options with long names. GDB will
6070 continue to accept the old forms (-option and +option) as well.
6071 Various single letter abbreviations for options have been explicity
6072 added to the option table so that they won't get overshadowed in the
6073 future by other options that begin with the same letter.
6077 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6078 Many assorted bugs have been handled. Many more remain to be handled.
6079 See the various ChangeLog files (primarily in gdb and bfd) for details.
6082 *** Changes in GDB-4.3:
6084 * New machines supported (host and target)
6086 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6087 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6088 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6090 * Almost SCO Unix support
6092 We had hoped to support:
6093 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6094 (except for core file support), but we discovered very late in the release
6095 that it has problems with process groups that render gdb unusable. Sorry
6096 about that. I encourage people to fix it and post the fixes.
6098 * Preliminary ELF and DWARF support
6100 GDB can read ELF object files on System V Release 4, and can handle
6101 debugging records for C, in DWARF format, in ELF files. This support
6102 is preliminary. If you bring up GDB on another SVR4 system, please
6103 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6108 GDB now uses the latest `readline' library. One user-visible change
6109 is that two tabs will list possible command completions, which previously
6110 required typing M-? (meta-question mark, or ESC ?).
6114 The `stepi' bug that many of you noticed has been squashed.
6115 Many bugs in C++ have been handled. Many more remain to be handled.
6116 See the various ChangeLog files (primarily in gdb and bfd) for details.
6118 * State of the MIPS world (in case you wondered):
6120 GDB can understand the symbol tables emitted by the compilers
6121 supplied by most vendors of MIPS-based machines, including DEC. These
6122 symbol tables are in a format that essentially nobody else uses.
6124 Some versions of gcc come with an assembler post-processor called
6125 mips-tfile. This program is required if you want to do source-level
6126 debugging of gcc-compiled programs. I believe FSF does not ship
6127 mips-tfile with gcc version 1, but it will eventually come with gcc
6130 Debugging of g++ output remains a problem. g++ version 1.xx does not
6131 really support it at all. (If you're lucky, you should be able to get
6132 line numbers and stack traces to work, but no parameters or local
6133 variables.) With some work it should be possible to improve the
6136 When gcc version 2 is released, you will have somewhat better luck.
6137 However, even then you will get confusing results for inheritance and
6140 We will eventually provide full debugging of g++ output on
6141 DECstations. This will probably involve some kind of stabs-in-ecoff
6142 encapulation, but the details have not been worked out yet.
6145 *** Changes in GDB-4.2:
6147 * Improved configuration
6149 Only one copy of `configure' exists now, and it is not self-modifying.
6150 Porting BFD is simpler.
6154 The `step' and `next' commands now only stop at the first instruction
6155 of a source line. This prevents the multiple stops that used to occur
6156 in switch statements, for-loops, etc. `Step' continues to stop if a
6157 function that has debugging information is called within the line.
6161 Lots of small bugs fixed. More remain.
6163 * New host supported (not target)
6165 Intel 386 PC clone running Mach i386-none-mach
6168 *** Changes in GDB-4.1:
6170 * Multiple source language support
6172 GDB now has internal scaffolding to handle several source languages.
6173 It determines the type of each source file from its filename extension,
6174 and will switch expression parsing and number formatting to match the
6175 language of the function in the currently selected stack frame.
6176 You can also specifically set the language to be used, with
6177 `set language c' or `set language modula-2'.
6181 GDB now has preliminary support for the GNU Modula-2 compiler,
6182 currently under development at the State University of New York at
6183 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6184 continue through the fall of 1991 and into 1992.
6186 Other Modula-2 compilers are currently not supported, and attempting to
6187 debug programs compiled with them will likely result in an error as the
6188 symbol table is read. Feel free to work on it, though!
6190 There are hooks in GDB for strict type checking and range checking,
6191 in the `Modula-2 philosophy', but they do not currently work.
6195 GDB can now write to executable and core files (e.g. patch
6196 a variable's value). You must turn this switch on, specify
6197 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6198 by assigning a new value to a variable. Modifications take
6201 * Automatic SunOS shared library reading
6203 When you run your program, GDB automatically determines where its
6204 shared libraries (if any) have been loaded, and reads their symbols.
6205 The `share' command is no longer needed. This also works when
6206 examining core files.
6210 You can specify the number of lines that the `list' command shows.
6213 * New machines supported (host and target)
6215 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6216 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6217 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6219 * New hosts supported (not targets)
6221 IBM RT/PC: romp-ibm-aix or rtpc
6223 * New targets supported (not hosts)
6225 AMD 29000 embedded with COFF a29k-none-coff
6226 AMD 29000 embedded with a.out a29k-none-aout
6227 Ultracomputer remote kernel debug a29k-nyu-kern
6229 * New remote interfaces
6235 *** Changes in GDB-4.0:
6239 Wide output is wrapped at good places to make the output more readable.
6241 Gdb now supports cross-debugging from a host machine of one type to a
6242 target machine of another type. Communication with the target system
6243 is over serial lines. The ``target'' command handles connecting to the
6244 remote system; the ``load'' command will download a program into the
6245 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6246 also supports debugging of realtime processes running under VxWorks,
6247 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6248 stub on the target system.
6250 New CPUs supported include the AMD 29000 and Intel 960.
6252 GDB now reads object files and symbol tables via a ``binary file''
6253 library, which allows a single copy of GDB to debug programs of multiple
6254 object file types such as a.out and coff.
6256 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6257 refcard.dvi and refcard.ps are available to format it).
6260 * Control-Variable user interface simplified
6262 All variables that control the operation of the debugger can be set
6263 by the ``set'' command, and displayed by the ``show'' command.
6265 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6266 ``Show prompt'' produces the response:
6267 Gdb's prompt is new-gdb=>.
6269 What follows are the NEW set commands. The command ``help set'' will
6270 print a complete list of old and new set commands. ``help set FOO''
6271 will give a longer description of the variable FOO. ``show'' will show
6272 all of the variable descriptions and their current settings.
6274 confirm on/off: Enables warning questions for operations that are
6275 hard to recover from, e.g. rerunning the program while
6276 it is already running. Default is ON.
6278 editing on/off: Enables EMACS style command line editing
6279 of input. Previous lines can be recalled with
6280 control-P, the current line can be edited with control-B,
6281 you can search for commands with control-R, etc.
6284 history filename NAME: NAME is where the gdb command history
6285 will be stored. The default is .gdb_history,
6286 or the value of the environment variable
6289 history size N: The size, in commands, of the command history. The
6290 default is 256, or the value of the environment variable
6293 history save on/off: If this value is set to ON, the history file will
6294 be saved after exiting gdb. If set to OFF, the
6295 file will not be saved. The default is OFF.
6297 history expansion on/off: If this value is set to ON, then csh-like
6298 history expansion will be performed on
6299 command line input. The default is OFF.
6301 radix N: Sets the default radix for input and output. It can be set
6302 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6303 in the current radix, so "set radix 10" is always a no-op.
6305 height N: This integer value is the number of lines on a page. Default
6306 is 24, the current `stty rows'' setting, or the ``li#''
6307 setting from the termcap entry matching the environment
6310 width N: This integer value is the number of characters on a line.
6311 Default is 80, the current `stty cols'' setting, or the ``co#''
6312 setting from the termcap entry matching the environment
6315 Note: ``set screensize'' is obsolete. Use ``set height'' and
6316 ``set width'' instead.
6318 print address on/off: Print memory addresses in various command displays,
6319 such as stack traces and structure values. Gdb looks
6320 more ``symbolic'' if you turn this off; it looks more
6321 ``machine level'' with it on. Default is ON.
6323 print array on/off: Prettyprint arrays. New convenient format! Default
6326 print demangle on/off: Print C++ symbols in "source" form if on,
6329 print asm-demangle on/off: Same, for assembler level printouts
6332 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6335 * Support for Epoch Environment.
6337 The epoch environment is a version of Emacs v18 with windowing. One
6338 new command, ``inspect'', is identical to ``print'', except that if you
6339 are running in the epoch environment, the value is printed in its own
6343 * Support for Shared Libraries
6345 GDB can now debug programs and core files that use SunOS shared libraries.
6346 Symbols from a shared library cannot be referenced
6347 before the shared library has been linked with the program (this
6348 happens after you type ``run'' and before the function main() is entered).
6349 At any time after this linking (including when examining core files
6350 from dynamically linked programs), gdb reads the symbols from each
6351 shared library when you type the ``sharedlibrary'' command.
6352 It can be abbreviated ``share''.
6354 sharedlibrary REGEXP: Load shared object library symbols for files
6355 matching a unix regular expression. No argument
6356 indicates to load symbols for all shared libraries.
6358 info sharedlibrary: Status of loaded shared libraries.
6363 A watchpoint stops execution of a program whenever the value of an
6364 expression changes. Checking for this slows down execution
6365 tremendously whenever you are in the scope of the expression, but is
6366 quite useful for catching tough ``bit-spreader'' or pointer misuse
6367 problems. Some machines such as the 386 have hardware for doing this
6368 more quickly, and future versions of gdb will use this hardware.
6370 watch EXP: Set a watchpoint (breakpoint) for an expression.
6372 info watchpoints: Information about your watchpoints.
6374 delete N: Deletes watchpoint number N (same as breakpoints).
6375 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6376 enable N: Re-enables watchpoint number N (same as breakpoints).
6379 * C++ multiple inheritance
6381 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6384 * C++ exception handling
6386 Gdb now supports limited C++ exception handling. Besides the existing
6387 ability to breakpoint on an exception handler, gdb can breakpoint on
6388 the raising of an exception (before the stack is peeled back to the
6391 catch FOO: If there is a FOO exception handler in the dynamic scope,
6392 set a breakpoint to catch exceptions which may be raised there.
6393 Multiple exceptions (``catch foo bar baz'') may be caught.
6395 info catch: Lists all exceptions which may be caught in the
6396 current stack frame.
6399 * Minor command changes
6401 The command ``call func (arg, arg, ...)'' now acts like the print
6402 command, except it does not print or save a value if the function's result
6403 is void. This is similar to dbx usage.
6405 The ``up'' and ``down'' commands now always print the frame they end up
6406 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6407 frames without printing.
6409 * New directory command
6411 'dir' now adds directories to the FRONT of the source search path.
6412 The path starts off empty. Source files that contain debug information
6413 about the directory in which they were compiled can be found even
6414 with an empty path; Sun CC and GCC include this information. If GDB can't
6415 find your source file in the current directory, type "dir .".
6417 * Configuring GDB for compilation
6419 For normal use, type ``./configure host''. See README or gdb.texinfo
6422 GDB now handles cross debugging. If you are remotely debugging between
6423 two different machines, type ``./configure host -target=targ''.
6424 Host is the machine where GDB will run; targ is the machine
6425 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob