1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.11
6 * GDB now supports multibit bitfields and enums in target register
9 * New Python-based convenience function $_as_string(val), which returns
10 the textual representation of a value. This function is especially
11 useful to obtain the text label of an enum value.
13 * Intel MPX bound violation handling.
15 Segmentation faults caused by a Intel MPX boundary violation
16 now display the kind of violation (upper or lower), the memory
17 address accessed and the memory bounds, along with the usual
18 signal received and code location.
22 Program received signal SIGSEGV, Segmentation fault
23 Upper bound violation while accessing address 0x7fffffffc3b3
24 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
25 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
30 skip -gfile file-glob-pattern
31 skip -function function
32 skip -rfunction regular-expression
33 A generalized form of the skip command, with new support for
34 glob-style file names and regular expressions for function names.
35 Additionally, a file spec and a function spec may now be combined.
37 maint info line-table REGEXP
38 Display the contents of GDB's internal line table data struture.
40 *** Changes in GDB 7.11
42 * GDB now supports debugging kernel-based threads on FreeBSD.
44 * Per-inferior thread numbers
46 Thread numbers are now per inferior instead of global. If you're
47 debugging multiple inferiors, GDB displays thread IDs using a
48 qualified INF_NUM.THR_NUM form. For example:
52 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
53 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
54 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
55 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
57 As consequence, thread numbers as visible in the $_thread
58 convenience variable and in Python's InferiorThread.num attribute
59 are no longer unique between inferiors.
61 GDB now maintains a second thread ID per thread, referred to as the
62 global thread ID, which is the new equivalent of thread numbers in
63 previous releases. See also $_gthread below.
65 For backwards compatibility, MI's thread IDs always refer to global
68 * Commands that accept thread IDs now accept the qualified
69 INF_NUM.THR_NUM form as well. For example:
72 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
75 * In commands that accept a list of thread IDs, you can now refer to
76 all threads of an inferior using a star wildcard. GDB accepts
77 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
78 refer to all threads of the current inferior. For example, "info
81 * You can use "info threads -gid" to display the global thread ID of
84 * The new convenience variable $_gthread holds the global number of
87 * The new convenience variable $_inferior holds the number of the
90 * GDB now displays the ID and name of the thread that hit a breakpoint
91 or received a signal, if your program is multi-threaded. For
94 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
95 Thread 1 "main" received signal SIGINT, Interrupt.
97 * Record btrace now supports non-stop mode.
99 * Support for tracepoints on aarch64-linux was added in GDBserver.
101 * The 'record instruction-history' command now indicates speculative execution
102 when using the Intel Processor Trace recording format.
104 * GDB now allows users to specify explicit locations, bypassing
105 the linespec parser. This feature is also available to GDB/MI
108 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
109 GDB now is able to debug both AArch64 applications and ARM applications
112 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
113 including JIT compiling fast tracepoint's conditional expression bytecode
116 * GDB now supports displaced stepping on AArch64 GNU/Linux.
118 * "info threads", "info inferiors", "info display", "info checkpoints"
119 and "maint info program-spaces" now list the corresponding items in
120 ascending ID order, for consistency with all other "info" commands.
122 * In Ada, the overloads selection menu has been enhanced to display the
123 parameter types and the return types for the matching overloaded subprograms.
127 maint set target-non-stop (on|off|auto)
128 maint show target-non-stop
129 Control whether GDB targets always operate in non-stop mode even if
130 "set non-stop" is "off". The default is "auto", meaning non-stop
131 mode is enabled if supported by the target.
133 maint set bfd-sharing
134 maint show bfd-sharing
135 Control the reuse of bfd objects.
139 Control display of debugging info regarding bfd caching.
143 Control display of debugging info regarding FreeBSD threads.
145 set remote multiprocess-extensions-packet
146 show remote multiprocess-extensions-packet
147 Set/show the use of the remote protocol multiprocess extensions.
149 set remote thread-events
150 show remote thread-events
151 Set/show the use of thread create/exit events.
153 set ada print-signatures on|off
154 show ada print-signatures"
155 Control whether parameter types and return types are displayed in overloads
156 selection menus. It is activaled (@code{on}) by default.
160 Controls the maximum size of memory, in bytes, that GDB will
161 allocate for value contents. Prevents incorrect programs from
162 causing GDB to allocate overly large buffers. Default is 64k.
164 * The "disassemble" command accepts a new modifier: /s.
165 It prints mixed source+disassembly like /m with two differences:
166 - disassembled instructions are now printed in program order, and
167 - and source for all relevant files is now printed.
168 The "/m" option is now considered deprecated: its "source-centric"
169 output hasn't proved useful in practice.
171 * The "record instruction-history" command accepts a new modifier: /s.
172 It behaves exactly like /m and prints mixed source+disassembly.
174 * The "set scheduler-locking" command supports a new mode "replay".
175 It behaves like "off" in record mode and like "on" in replay mode.
177 * Support for various ROM monitors has been removed:
179 target dbug dBUG ROM monitor for Motorola ColdFire
180 target picobug Motorola picobug monitor
181 target dink32 DINK32 ROM monitor for PowerPC
182 target m32r Renesas M32R/D ROM monitor
183 target mon2000 mon2000 ROM monitor
184 target ppcbug PPCBUG ROM monitor for PowerPC
186 * Support for reading/writing memory and extracting values on architectures
187 whose memory is addressable in units of any integral multiple of 8 bits.
192 Indicates that an exec system call was executed.
194 exec-events feature in qSupported
195 The qSupported packet allows GDB to request support for exec
196 events using the new 'gdbfeature' exec-event, and the qSupported
197 response can contain the corresponding 'stubfeature'. Set and
198 show commands can be used to display whether these features are enabled.
201 Equivalent to interrupting with the ^C character, but works in
204 thread created stop reason (T05 create:...)
205 Indicates that the thread was just created and is stopped at entry.
207 thread exit stop reply (w exitcode;tid)
208 Indicates that the thread has terminated.
211 Enables/disables thread create and exit event reporting. For
212 example, this is used in non-stop mode when GDB stops a set of
213 threads and synchronously waits for the their corresponding stop
214 replies. Without exit events, if one of the threads exits, GDB
215 would hang forever not knowing that it should no longer expect a
216 stop for that same thread.
220 Indicates that there are no resumed threads left in the target (all
221 threads are stopped). The remote stub reports support for this stop
222 reply to GDB's qSupported query.
224 QCatchSyscalls:1 [;SYSNO]...
226 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
227 catching syscalls from the inferior process.
229 syscall_entry stop reason
230 Indicates that a syscall was just called.
232 syscall_return stop reason
233 Indicates that a syscall just returned.
235 QCatchSyscalls:1 in qSupported
236 The qSupported packet may now include QCatchSyscalls:1 in the reply
237 to indicate support for catching syscalls.
239 * Extended-remote exec events
241 ** GDB now has support for exec events on extended-remote Linux targets.
242 For such targets with Linux kernels 2.5.46 and later, this enables
243 follow-exec-mode and exec catchpoints.
245 set remote exec-event-feature-packet
246 show remote exec-event-feature-packet
247 Set/show the use of the remote exec event feature.
249 * Thread names in remote protocol
251 The reply to qXfer:threads:read may now include a name attribute for each
254 * Target remote mode fork and exec events
256 ** GDB now has support for fork and exec events on target remote mode
257 Linux targets. For such targets with Linux kernels 2.5.46 and later,
258 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
259 fork and exec catchpoints.
261 * Remote syscall events
263 ** GDB now has support for catch syscall on remote Linux targets,
264 currently enabled on x86/x86_64 architectures.
266 set remote catch-syscall-packet
267 show remote catch-syscall-packet
268 Set/show the use of the remote catch syscall feature.
272 ** The -var-set-format command now accepts the zero-hexadecimal
273 format. It outputs data in hexadecimal format with zero-padding on the
278 ** gdb.InferiorThread objects have a new attribute "global_num",
279 which refers to the thread's global thread ID. The existing
280 "num" attribute now refers to the thread's per-inferior number.
281 See "Per-inferior thread numbers" above.
282 ** gdb.InferiorThread objects have a new attribute "inferior", which
283 is the Inferior object the thread belongs to.
285 *** Changes in GDB 7.10
287 * Support for process record-replay and reverse debugging on aarch64*-linux*
288 targets has been added. GDB now supports recording of A64 instruction set
289 including advance SIMD instructions.
291 * Support for Sun's version of the "stabs" debug file format has been removed.
293 * GDB now honors the content of the file /proc/PID/coredump_filter
294 (PID is the process ID) on GNU/Linux systems. This file can be used
295 to specify the types of memory mappings that will be included in a
296 corefile. For more information, please refer to the manual page of
297 "core(5)". GDB also has a new command: "set use-coredump-filter
298 on|off". It allows to set whether GDB will read the content of the
299 /proc/PID/coredump_filter file when generating a corefile.
301 * The "info os" command on GNU/Linux can now display information on
303 "info os cpus" Listing of all cpus/cores on the system
305 * GDB has two new commands: "set serial parity odd|even|none" and
306 "show serial parity". These allows to set or show parity for the
309 * The "info source" command now displays the producer string if it was
310 present in the debug info. This typically includes the compiler version
311 and may include things like its command line arguments.
313 * The "info dll", an alias of the "info sharedlibrary" command,
314 is now available on all platforms.
316 * Directory names supplied to the "set sysroot" commands may be
317 prefixed with "target:" to tell GDB to access shared libraries from
318 the target system, be it local or remote. This replaces the prefix
319 "remote:". The default sysroot has been changed from "" to
320 "target:". "remote:" is automatically converted to "target:" for
321 backward compatibility.
323 * The system root specified by "set sysroot" will be prepended to the
324 filename of the main executable (if reported to GDB as absolute by
325 the operating system) when starting processes remotely, and when
326 attaching to already-running local or remote processes.
328 * GDB now supports automatic location and retrieval of executable
329 files from remote targets. Remote debugging can now be initiated
330 using only a "target remote" or "target extended-remote" command
331 (no "set sysroot" or "file" commands are required). See "New remote
334 * The "dump" command now supports verilog hex format.
336 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
338 * On GNU/Linux, GDB and gdbserver are now able to access executable
339 and shared library files without a "set sysroot" command when
340 attaching to processes running in different mount namespaces from
341 the debugger. This makes it possible to attach to processes in
342 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
343 See "New remote packets" below.
345 * The "tui reg" command now provides completion for all of the
346 available register groups, including target specific groups.
348 * The HISTSIZE environment variable is no longer read when determining
349 the size of GDB's command history. GDB now instead reads the dedicated
350 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
351 disables truncation of command history. Non-numeric values of GDBHISTSIZE
356 ** Memory ports can now be unbuffered.
360 ** gdb.Objfile objects have a new attribute "username",
361 which is the name of the objfile as specified by the user,
362 without, for example, resolving symlinks.
363 ** You can now write frame unwinders in Python.
364 ** gdb.Type objects have a new method "optimized_out",
365 returning optimized out gdb.Value instance of this type.
366 ** gdb.Value objects have new methods "reference_value" and
367 "const_value" which return a reference to the value and a
368 "const" version of the value respectively.
372 maint print symbol-cache
373 Print the contents of the symbol cache.
375 maint print symbol-cache-statistics
376 Print statistics of symbol cache usage.
378 maint flush-symbol-cache
379 Flush the contents of the symbol cache.
383 Start branch trace recording using Branch Trace Store (BTS) format.
386 Evaluate expression by using the compiler and print result.
390 Explicit commands for enabling and disabling tui mode.
393 set mpx bound on i386 and amd64
394 Support for bound table investigation on Intel MPX enabled applications.
398 Start branch trace recording using Intel Processor Trace format.
401 Print information about branch tracing internals.
403 maint btrace packet-history
404 Print the raw branch tracing data.
406 maint btrace clear-packet-history
407 Discard the stored raw branch tracing data.
410 Discard all branch tracing data. It will be fetched and processed
411 anew by the next "record" command.
416 Renamed from "set debug dwarf2-die".
418 Renamed from "show debug dwarf2-die".
421 Renamed from "set debug dwarf2-read".
422 show debug dwarf-read
423 Renamed from "show debug dwarf2-read".
425 maint set dwarf always-disassemble
426 Renamed from "maint set dwarf2 always-disassemble".
427 maint show dwarf always-disassemble
428 Renamed from "maint show dwarf2 always-disassemble".
430 maint set dwarf max-cache-age
431 Renamed from "maint set dwarf2 max-cache-age".
432 maint show dwarf max-cache-age
433 Renamed from "maint show dwarf2 max-cache-age".
436 show debug dwarf-line
437 Control display of debugging info regarding DWARF line processing.
441 Set the maximum number of candidates to be considered during
442 completion. The default value is 200. This limit allows GDB
443 to avoid generating large completion lists, the computation of
444 which can cause the debugger to become temporarily unresponsive.
446 set history remove-duplicates
447 show history remove-duplicates
448 Control the removal of duplicate history entries.
450 maint set symbol-cache-size
451 maint show symbol-cache-size
452 Control the size of the symbol cache.
454 set|show record btrace bts buffer-size
455 Set and show the size of the ring buffer used for branch tracing in
457 The obtained size may differ from the requested size. Use "info
458 record" to see the obtained buffer size.
460 set debug linux-namespaces
461 show debug linux-namespaces
462 Control display of debugging info regarding Linux namespaces.
464 set|show record btrace pt buffer-size
465 Set and show the size of the ring buffer used for branch tracing in
466 Intel Processor Trace format.
467 The obtained size may differ from the requested size. Use "info
468 record" to see the obtained buffer size.
470 maint set|show btrace pt skip-pad
471 Set and show whether PAD packets are skipped when computing the
474 * The command 'thread apply all' can now support new option '-ascending'
475 to call its specified command for all threads in ascending order.
477 * Python/Guile scripting
479 ** GDB now supports auto-loading of Python/Guile scripts contained in the
480 special section named `.debug_gdb_scripts'.
484 qXfer:btrace-conf:read
485 Return the branch trace configuration for the current thread.
487 Qbtrace-conf:bts:size
488 Set the requested ring buffer size for branch tracing in BTS format.
491 Enable Intel Procesor Trace-based branch tracing for the current
492 process. The remote stub reports support for this packet to GDB's
496 Set the requested ring buffer size for branch tracing in Intel Processor
500 Indicates a memory breakpoint instruction was executed, irrespective
501 of whether it was GDB that planted the breakpoint or the breakpoint
502 is hardcoded in the program. This is required for correct non-stop
506 Indicates the target stopped for a hardware breakpoint. This is
507 required for correct non-stop mode operation.
510 Return information about files on the remote system.
513 Return the full absolute name of the file that was executed to
514 create a process running on the remote system.
517 Select the filesystem on which vFile: operations with filename
518 arguments will operate. This is required for GDB to be able to
519 access files on remote targets where the remote stub does not
520 share a common filesystem with the inferior(s).
523 Indicates that a fork system call was executed.
526 Indicates that a vfork system call was executed.
528 vforkdone stop reason
529 Indicates that a vfork child of the specified process has executed
530 an exec or exit, allowing the vfork parent to resume execution.
532 fork-events and vfork-events features in qSupported
533 The qSupported packet allows GDB to request support for fork and
534 vfork events using new 'gdbfeatures' fork-events and vfork-events,
535 and the qSupported response can contain the corresponding
536 'stubfeatures'. Set and show commands can be used to display
537 whether these features are enabled.
539 * Extended-remote fork events
541 ** GDB now has support for fork events on extended-remote Linux
542 targets. For targets with Linux kernels 2.5.60 and later, this
543 enables follow-fork-mode and detach-on-fork for both fork and
544 vfork, as well as fork and vfork catchpoints.
546 * The info record command now shows the recording format and the
547 branch tracing configuration for the current thread when using
548 the btrace record target.
549 For the BTS format, it shows the ring buffer size.
551 * GDB now has support for DTrace USDT (Userland Static Defined
552 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
554 * GDB now supports access to vector registers on S/390 GNU/Linux
557 * Removed command line options
559 -xdb HP-UX XDB compatibility mode.
561 * Removed targets and native configurations
563 HP/PA running HP-UX hppa*-*-hpux*
564 Itanium running HP-UX ia64-*-hpux*
566 * New configure options
569 This configure option allows the user to build GDB with support for
570 Intel Processor Trace (default: auto). This requires libipt.
572 --with-libipt-prefix=PATH
573 Specify the path to the version of libipt that GDB should use.
574 $PATH/include should contain the intel-pt.h header and
575 $PATH/lib should contain the libipt.so library.
577 *** Changes in GDB 7.9.1
581 ** Xmethods can now specify a result type.
583 *** Changes in GDB 7.9
585 * GDB now supports hardware watchpoints on x86 GNU Hurd.
589 ** You can now access frame registers from Python scripts.
590 ** New attribute 'producer' for gdb.Symtab objects.
591 ** gdb.Objfile objects have a new attribute "progspace",
592 which is the gdb.Progspace object of the containing program space.
593 ** gdb.Objfile objects have a new attribute "owner".
594 ** gdb.Objfile objects have a new attribute "build_id",
595 which is the build ID generated when the file was built.
596 ** gdb.Objfile objects have a new method "add_separate_debug_file".
597 ** A new event "gdb.clear_objfiles" has been added, triggered when
598 selecting a new file to debug.
599 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
600 ** New function gdb.lookup_objfile.
602 New events which are triggered when GDB modifies the state of the
605 ** gdb.events.inferior_call_pre: Function call is about to be made.
606 ** gdb.events.inferior_call_post: Function call has just been made.
607 ** gdb.events.memory_changed: A memory location has been altered.
608 ** gdb.events.register_changed: A register has been altered.
610 * New Python-based convenience functions:
612 ** $_caller_is(name [, number_of_frames])
613 ** $_caller_matches(regexp [, number_of_frames])
614 ** $_any_caller_is(name [, number_of_frames])
615 ** $_any_caller_matches(regexp [, number_of_frames])
617 * GDB now supports the compilation and injection of source code into
618 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
619 to compile the source code to object code, and if successful, inject
620 and execute that code within the current context of the inferior.
621 Currently the C language is supported. The commands used to
622 interface with this new feature are:
624 compile code [-raw|-r] [--] [source code]
625 compile file [-raw|-r] filename
629 demangle [-l language] [--] name
630 Demangle "name" in the specified language, or the current language
631 if elided. This command is renamed from the "maint demangle" command.
632 The latter is kept as a no-op to avoid "maint demangle" being interpreted
633 as "maint demangler-warning".
635 queue-signal signal-name-or-number
636 Queue a signal to be delivered to the thread when it is resumed.
638 add-auto-load-scripts-directory directory
639 Add entries to the list of directories from which to load auto-loaded
642 maint print user-registers
643 List all currently available "user" registers.
645 compile code [-r|-raw] [--] [source code]
646 Compile, inject, and execute in the inferior the executable object
647 code produced by compiling the provided source code.
649 compile file [-r|-raw] filename
650 Compile and inject into the inferior the executable object code
651 produced by compiling the source code stored in the filename
654 * On resume, GDB now always passes the signal the program had stopped
655 for to the thread the signal was sent to, even if the user changed
656 threads before resuming. Previously GDB would often (but not
657 always) deliver the signal to the thread that happens to be current
660 * Conversely, the "signal" command now consistently delivers the
661 requested signal to the current thread. GDB now asks for
662 confirmation if the program had stopped for a signal and the user
663 switched threads meanwhile.
665 * "breakpoint always-inserted" modes "off" and "auto" merged.
667 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
668 won't remove breakpoints from the target until all threads stop,
669 even in non-stop mode. The "auto" mode has been removed, and "off"
670 is now the default mode.
674 set debug symbol-lookup
675 show debug symbol-lookup
676 Control display of debugging info regarding symbol lookup.
680 ** The -list-thread-groups command outputs an exit-code field for
681 inferiors that have exited.
685 MIPS SDE mips*-sde*-elf*
689 Support for these obsolete configurations has been removed.
691 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
692 SGI Irix-5.x mips-*-irix5*
693 SGI Irix-6.x mips-*-irix6*
694 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
695 VAX running Ultrix vax-*-ultrix*
697 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
698 and "assf"), have been removed. Use the "sharedlibrary" command, or
699 its alias "share", instead.
701 *** Changes in GDB 7.8
703 * New command line options
706 This is an alias for the --data-directory option.
708 * GDB supports printing and modifying of variable length automatic arrays
709 as specified in ISO C99.
711 * The ARM simulator now supports instruction level tracing
712 with or without disassembly.
716 GDB now has support for scripting using Guile. Whether this is
717 available is determined at configure time.
718 Guile version 2.0 or greater is required.
719 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
721 * New commands (for set/show, see "New options" below)
725 Invoke CODE by passing it to the Guile interpreter.
729 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
731 info auto-load guile-scripts [regexp]
732 Print the list of automatically loaded Guile scripts.
734 * The source command is now capable of sourcing Guile scripts.
735 This feature is dependent on the debugger being built with Guile support.
739 set print symbol-loading (off|brief|full)
740 show print symbol-loading
741 Control whether to print informational messages when loading symbol
742 information for a file. The default is "full", but when debugging
743 programs with large numbers of shared libraries the amount of output
746 set guile print-stack (none|message|full)
747 show guile print-stack
748 Show a stack trace when an error is encountered in a Guile script.
750 set auto-load guile-scripts (on|off)
751 show auto-load guile-scripts
752 Control auto-loading of Guile script files.
754 maint ada set ignore-descriptive-types (on|off)
755 maint ada show ignore-descriptive-types
756 Control whether the debugger should ignore descriptive types in Ada
757 programs. The default is not to ignore the descriptive types. See
758 the user manual for more details on descriptive types and the intended
759 usage of this option.
761 set auto-connect-native-target
763 Control whether GDB is allowed to automatically connect to the
764 native target for the run, attach, etc. commands when not connected
765 to any target yet. See also "target native" below.
767 set record btrace replay-memory-access (read-only|read-write)
768 show record btrace replay-memory-access
769 Control what memory accesses are allowed during replay.
771 maint set target-async (on|off)
772 maint show target-async
773 This controls whether GDB targets operate in synchronous or
774 asynchronous mode. Normally the default is asynchronous, if it is
775 available; but this can be changed to more easily debug problems
776 occurring only in synchronous mode.
778 set mi-async (on|off)
780 Control whether MI asynchronous mode is preferred. This supersedes
781 "set target-async" of previous GDB versions.
783 * "set target-async" is deprecated as a CLI option and is now an alias
784 for "set mi-async" (only puts MI into async mode).
786 * Background execution commands (e.g., "c&", "s&", etc.) are now
787 possible ``out of the box'' if the target supports them. Previously
788 the user would need to explicitly enable the possibility with the
789 "set target-async on" command.
791 * New features in the GDB remote stub, GDBserver
793 ** New option --debug-format=option1[,option2,...] allows one to add
794 additional text to each output. At present only timestamps
795 are supported: --debug-format=timestamps.
796 Timestamps can also be turned on with the
797 "monitor set debug-format timestamps" command from GDB.
799 * The 'record instruction-history' command now starts counting instructions
800 at one. This also affects the instruction ranges reported by the
801 'record function-call-history' command when given the /i modifier.
803 * The command 'record function-call-history' supports a new modifier '/c' to
804 indent the function names based on their call stack depth.
805 The fields for the '/i' and '/l' modifier have been reordered.
806 The source line range is now prefixed with 'at'.
807 The instruction range is now prefixed with 'inst'.
808 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
809 "record instruction-history" and "list" commands.
811 * The ranges given as arguments to the 'record function-call-history' and
812 'record instruction-history' commands are now inclusive.
814 * The btrace record target now supports the 'record goto' command.
815 For locations inside the execution trace, the back trace is computed
816 based on the information stored in the execution trace.
818 * The btrace record target supports limited reverse execution and replay.
819 The target does not record data and therefore does not allow reading
822 * The "catch syscall" command now works on s390*-linux* targets.
824 * The "compare-sections" command is no longer specific to target
825 remote. It now works with all targets.
827 * All native targets are now consistently called "native".
828 Consequently, the "target child", "target GNU", "target djgpp",
829 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
830 commands have been replaced with "target native". The QNX/NTO port
831 leaves the "procfs" target in place and adds a "native" target for
832 consistency with other ports. The impact on users should be minimal
833 as these commands previously either throwed an error, or were
834 no-ops. The target's name is visible in the output of the following
835 commands: "help target", "info target", "info files", "maint print
838 * The "target native" command now connects to the native target. This
839 can be used to launch native programs even when "set
840 auto-connect-native-target" is set to off.
842 * GDB now supports access to Intel MPX registers on GNU/Linux.
844 * Support for Intel AVX-512 registers on GNU/Linux.
845 Support displaying and modifying Intel AVX-512 registers
846 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
850 qXfer:btrace:read's annex
851 The qXfer:btrace:read packet supports a new annex 'delta' to read
852 branch trace incrementally.
856 ** Valid Python operations on gdb.Value objects representing
857 structs/classes invoke the corresponding overloaded operators if
859 ** New `Xmethods' feature in the Python API. Xmethods are
860 additional methods or replacements for existing methods of a C++
861 class. This feature is useful for those cases where a method
862 defined in C++ source code could be inlined or optimized out by
863 the compiler, making it unavailable to GDB.
866 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
868 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
869 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
870 its alias "share", instead.
872 * The commands "set remotebaud" and "show remotebaud" are no longer
873 supported. Use "set serial baud" and "show serial baud" (respectively)
878 ** A new option "-gdb-set mi-async" replaces "-gdb-set
879 target-async". The latter is left as a deprecated alias of the
880 former for backward compatibility. If the target supports it,
881 CLI background execution commands are now always possible by
882 default, independently of whether the frontend stated a
883 preference for asynchronous execution with "-gdb-set mi-async".
884 Previously "-gdb-set target-async off" affected both MI execution
885 commands and CLI execution commands.
887 *** Changes in GDB 7.7
889 * Improved support for process record-replay and reverse debugging on
890 arm*-linux* targets. Support for thumb32 and syscall instruction
891 recording has been added.
893 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
895 * GDB now supports Fission DWP file format version 2.
896 http://gcc.gnu.org/wiki/DebugFission
898 * New convenience function "$_isvoid", to check whether an expression
899 is void. A void expression is an expression where the type of the
900 result is "void". For example, some convenience variables may be
901 "void" when evaluated (e.g., "$_exitcode" before the execution of
902 the program being debugged; or an undefined convenience variable).
903 Another example, when calling a function whose return type is
906 * The "maintenance print objfiles" command now takes an optional regexp.
908 * The "catch syscall" command now works on arm*-linux* targets.
910 * GDB now consistently shows "<not saved>" when printing values of
911 registers the debug info indicates have not been saved in the frame
912 and there's nowhere to retrieve them from
913 (callee-saved/call-clobbered registers):
918 (gdb) info registers rax
921 Before, the former would print "<optimized out>", and the latter
922 "*value not available*".
924 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
929 ** Frame filters and frame decorators have been added.
930 ** Temporary breakpoints are now supported.
931 ** Line tables representation has been added.
932 ** New attribute 'parent_type' for gdb.Field objects.
933 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
934 ** New attribute 'name' for gdb.Type objects.
938 Nios II ELF nios2*-*-elf
939 Nios II GNU/Linux nios2*-*-linux
940 Texas Instruments MSP430 msp430*-*-elf
942 * Removed native configurations
944 Support for these a.out NetBSD and OpenBSD obsolete configurations has
945 been removed. ELF variants of these configurations are kept supported.
947 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
948 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
949 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
950 i[34567]86-*-openbsd3.[0-3]
951 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
952 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
953 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
957 Like "catch throw", but catches a re-thrown exception.
959 Renamed from old "maint check-symtabs".
961 Perform consistency checks on symtabs.
963 Expand symtabs matching an optional regexp.
966 Display the details of GDB configure-time options.
968 maint set|show per-command
969 maint set|show per-command space
970 maint set|show per-command time
971 maint set|show per-command symtab
972 Enable display of per-command gdb resource usage.
974 remove-symbol-file FILENAME
975 remove-symbol-file -a ADDRESS
976 Remove a symbol file added via add-symbol-file. The file to remove
977 can be identified by its filename or by an address that lies within
978 the boundaries of this symbol file in memory.
981 info exceptions REGEXP
982 Display the list of Ada exceptions defined in the program being
983 debugged. If provided, only the exceptions whose names match REGEXP
988 set debug symfile off|on
990 Control display of debugging info regarding reading symbol files and
991 symbol tables within those files
993 set print raw frame-arguments
994 show print raw frame-arguments
995 Set/show whether to print frame arguments in raw mode,
996 disregarding any defined pretty-printers.
998 set remote trace-status-packet
999 show remote trace-status-packet
1000 Set/show the use of remote protocol qTStatus packet.
1004 Control display of debugging messages related to Nios II targets.
1008 Control whether target-assisted range stepping is enabled.
1010 set startup-with-shell
1011 show startup-with-shell
1012 Specifies whether Unix child processes are started via a shell or
1017 Use the target memory cache for accesses to the code segment. This
1018 improves performance of remote debugging (particularly disassembly).
1020 * You can now use a literal value 'unlimited' for options that
1021 interpret 0 or -1 as meaning "unlimited". E.g., "set
1022 trace-buffer-size unlimited" is now an alias for "set
1023 trace-buffer-size -1" and "set height unlimited" is now an alias for
1026 * The "set debug symtab-create" debugging option of GDB has been changed to
1027 accept a verbosity level. 0 means "off", 1 provides basic debugging
1028 output, and values of 2 or greater provides more verbose output.
1030 * New command-line options
1032 Display the details of GDB configure-time options.
1034 * The command 'tsave' can now support new option '-ctf' to save trace
1035 buffer in Common Trace Format.
1037 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1040 * GDB now implements the the C++ 'typeid' operator.
1042 * The new convenience variable $_exception holds the exception being
1043 thrown or caught at an exception-related catchpoint.
1045 * The exception-related catchpoints, like "catch throw", now accept a
1046 regular expression which can be used to filter exceptions by type.
1048 * The new convenience variable $_exitsignal is automatically set to
1049 the terminating signal number when the program being debugged dies
1050 due to an uncaught signal.
1054 ** All MI commands now accept an optional "--language" option.
1055 Support for this feature can be verified by using the "-list-features"
1056 command, which should contain "language-option".
1058 ** The new command -info-gdb-mi-command allows the user to determine
1059 whether a GDB/MI command is supported or not.
1061 ** The "^error" result record returned when trying to execute an undefined
1062 GDB/MI command now provides a variable named "code" whose content is the
1063 "undefined-command" error code. Support for this feature can be verified
1064 by using the "-list-features" command, which should contain
1065 "undefined-command-error-code".
1067 ** The -trace-save MI command can optionally save trace buffer in Common
1070 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1072 ** The command -data-list-register-values now accepts an optional
1073 "--skip-unavailable" option. When used, only the available registers
1076 ** The new command -trace-frame-collected dumps collected variables,
1077 computed expressions, tvars, memory and registers in a traceframe.
1079 ** The commands -stack-list-locals, -stack-list-arguments and
1080 -stack-list-variables now accept an option "--skip-unavailable".
1081 When used, only the available locals or arguments are displayed.
1083 ** The -exec-run command now accepts an optional "--start" option.
1084 When used, the command follows the same semantics as the "start"
1085 command, stopping the program's execution at the start of its
1086 main subprogram. Support for this feature can be verified using
1087 the "-list-features" command, which should contain
1088 "exec-run-start-option".
1090 ** The new commands -catch-assert and -catch-exceptions insert
1091 catchpoints stopping the program when Ada exceptions are raised.
1093 ** The new command -info-ada-exceptions provides the equivalent of
1094 the new "info exceptions" command.
1096 * New system-wide configuration scripts
1097 A GDB installation now provides scripts suitable for use as system-wide
1098 configuration scripts for the following systems:
1102 * GDB now supports target-assigned range stepping with remote targets.
1103 This improves the performance of stepping source lines by reducing
1104 the number of control packets from/to GDB. See "New remote packets"
1107 * GDB now understands the element 'tvar' in the XML traceframe info.
1108 It has the id of the collected trace state variables.
1110 * On S/390 targets that provide the transactional-execution feature,
1111 the program interruption transaction diagnostic block (TDB) is now
1112 represented as a number of additional "registers" in GDB.
1114 * New remote packets
1118 The vCont packet supports a new 'r' action, that tells the remote
1119 stub to step through an address range itself, without GDB
1120 involvemement at each single-step.
1122 qXfer:libraries-svr4:read's annex
1123 The previously unused annex of the qXfer:libraries-svr4:read packet
1124 is now used to support passing an argument list. The remote stub
1125 reports support for this argument list to GDB's qSupported query.
1126 The defined arguments are "start" and "prev", used to reduce work
1127 necessary for library list updating, resulting in significant
1130 * New features in the GDB remote stub, GDBserver
1132 ** GDBserver now supports target-assisted range stepping. Currently
1133 enabled on x86/x86_64 GNU/Linux targets.
1135 ** GDBserver now adds element 'tvar' in the XML in the reply to
1136 'qXfer:traceframe-info:read'. It has the id of the collected
1137 trace state variables.
1139 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1142 * New 'z' formatter for printing and examining memory, this displays the
1143 value as hexadecimal zero padded on the left to the size of the type.
1145 * GDB can now use Windows x64 unwinding data.
1147 * The "set remotebaud" command has been replaced by "set serial baud".
1148 Similarly, "show remotebaud" has been replaced by "show serial baud".
1149 The "set remotebaud" and "show remotebaud" commands are still available
1150 to provide backward compatibility with older versions of GDB.
1152 *** Changes in GDB 7.6
1154 * Target record has been renamed to record-full.
1155 Record/replay is now enabled with the "record full" command.
1156 This also affects settings that are associated with full record/replay
1157 that have been moved from "set/show record" to "set/show record full":
1159 set|show record full insn-number-max
1160 set|show record full stop-at-limit
1161 set|show record full memory-query
1163 * A new record target "record-btrace" has been added. The new target
1164 uses hardware support to record the control-flow of a process. It
1165 does not support replaying the execution, but it implements the
1166 below new commands for investigating the recorded execution log.
1167 This new recording method can be enabled using:
1171 The "record-btrace" target is only available on Intel Atom processors
1172 and requires a Linux kernel 2.6.32 or later.
1174 * Two new commands have been added for record/replay to give information
1175 about the recorded execution without having to replay the execution.
1176 The commands are only supported by "record btrace".
1178 record instruction-history prints the execution history at
1179 instruction granularity
1181 record function-call-history prints the execution history at
1182 function granularity
1184 * New native configurations
1186 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1187 FreeBSD/powerpc powerpc*-*-freebsd
1188 x86_64/Cygwin x86_64-*-cygwin*
1189 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1193 ARM AArch64 aarch64*-*-elf
1194 ARM AArch64 GNU/Linux aarch64*-*-linux
1195 Lynx 178 PowerPC powerpc-*-lynx*178
1196 x86_64/Cygwin x86_64-*-cygwin*
1197 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1199 * If the configured location of system.gdbinit file (as given by the
1200 --with-system-gdbinit option at configure time) is in the
1201 data-directory (as specified by --with-gdb-datadir at configure
1202 time) or in one of its subdirectories, then GDB will look for the
1203 system-wide init file in the directory specified by the
1204 --data-directory command-line option.
1206 * New command line options:
1208 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1209 other initialization files, unlike -nx which disables all of them.
1211 * Removed command line options
1213 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1216 * The 'ptype' and 'whatis' commands now accept an argument to control
1219 * 'info proc' now works on some core files.
1223 ** Vectors can be created with gdb.Type.vector.
1225 ** Python's atexit.register now works in GDB.
1227 ** Types can be pretty-printed via a Python API.
1229 ** Python 3 is now supported (in addition to Python 2.4 or later)
1231 ** New class gdb.Architecture exposes GDB's internal representation
1232 of architecture in the Python API.
1234 ** New method Frame.architecture returns the gdb.Architecture object
1235 corresponding to the frame's architecture.
1237 * New Python-based convenience functions:
1239 ** $_memeq(buf1, buf2, length)
1240 ** $_streq(str1, str2)
1242 ** $_regex(str, regex)
1244 * The 'cd' command now defaults to using '~' (the home directory) if not
1247 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1248 default for GCC since November 2000.
1250 * The command 'forward-search' can now be abbreviated as 'fo'.
1252 * The command 'info tracepoints' can now display 'installed on target'
1253 or 'not installed on target' for each non-pending location of tracepoint.
1255 * New configure options
1257 --enable-libmcheck/--disable-libmcheck
1258 By default, development versions are built with -lmcheck on hosts
1259 that support it, in order to help track memory corruption issues.
1260 Release versions, on the other hand, are built without -lmcheck
1261 by default. The --enable-libmcheck/--disable-libmcheck configure
1262 options allow the user to override that default.
1263 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1264 This configure option allows the user to build GDB with
1265 libbabeltrace using which GDB can read Common Trace Format data.
1267 * New commands (for set/show, see "New options" below)
1270 Catch signals. This is similar to "handle", but allows commands and
1271 conditions to be attached.
1274 List the BFDs known to GDB.
1276 python-interactive [command]
1278 Start a Python interactive prompt, or evaluate the optional command
1279 and print the result of expressions.
1282 "py" is a new alias for "python".
1284 enable type-printer [name]...
1285 disable type-printer [name]...
1286 Enable or disable type printers.
1290 ** For the Renesas Super-H architecture, the "regs" command has been removed
1291 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1296 set print type methods (on|off)
1297 show print type methods
1298 Control whether method declarations are displayed by "ptype".
1299 The default is to show them.
1301 set print type typedefs (on|off)
1302 show print type typedefs
1303 Control whether typedef definitions are displayed by "ptype".
1304 The default is to show them.
1306 set filename-display basename|relative|absolute
1307 show filename-display
1308 Control the way in which filenames is displayed.
1309 The default is "relative", which preserves previous behavior.
1311 set trace-buffer-size
1312 show trace-buffer-size
1313 Request target to change the size of trace buffer.
1315 set remote trace-buffer-size-packet auto|on|off
1316 show remote trace-buffer-size-packet
1317 Control the use of the remote protocol `QTBuffer:size' packet.
1321 Control display of debugging messages related to ARM AArch64.
1324 set debug coff-pe-read
1325 show debug coff-pe-read
1326 Control display of debugging messages related to reading of COFF/PE
1331 Control display of debugging messages related to Mach-O symbols
1334 set debug notification
1335 show debug notification
1336 Control display of debugging info for async remote notification.
1340 ** Command parameter changes are now notified using new async record
1341 "=cmd-param-changed".
1342 ** Trace frame changes caused by command "tfind" are now notified using
1343 new async record "=traceframe-changed".
1344 ** The creation, deletion and modification of trace state variables
1345 are now notified using new async records "=tsv-created",
1346 "=tsv-deleted" and "=tsv-modified".
1347 ** The start and stop of process record are now notified using new
1348 async record "=record-started" and "=record-stopped".
1349 ** Memory changes are now notified using new async record
1351 ** The data-disassemble command response will include a "fullname" field
1352 containing the absolute file name when source has been requested.
1353 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1354 command, to allow pattern filling of memory areas.
1355 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1356 library load/unload events.
1357 ** The response to breakpoint commands and breakpoint async records
1358 includes an "installed" field containing a boolean state about each
1359 non-pending tracepoint location is whether installed on target or not.
1360 ** Output of the "-trace-status" command includes a "trace-file" field
1361 containing the name of the trace file being examined. This field is
1362 optional, and only present when examining a trace file.
1363 ** The "fullname" field is now always present along with the "file" field,
1364 even if the file cannot be found by GDB.
1366 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1367 You must have the LZMA library available when configuring GDB for this
1368 feature to be enabled. For more information, see:
1369 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1371 * New remote packets
1374 Set the size of trace buffer. The remote stub reports support for this
1375 packet to gdb's qSupported query.
1378 Enable Branch Trace Store (BTS)-based branch tracing for the current
1379 thread. The remote stub reports support for this packet to gdb's
1383 Disable branch tracing for the current thread. The remote stub reports
1384 support for this packet to gdb's qSupported query.
1387 Read the traced branches for the current thread. The remote stub
1388 reports support for this packet to gdb's qSupported query.
1390 *** Changes in GDB 7.5
1392 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1393 for more x32 ABI info.
1395 * GDB now supports access to MIPS DSP registers on Linux targets.
1397 * GDB now supports debugging microMIPS binaries.
1399 * The "info os" command on GNU/Linux can now display information on
1400 several new classes of objects managed by the operating system:
1401 "info os procgroups" lists process groups
1402 "info os files" lists file descriptors
1403 "info os sockets" lists internet-domain sockets
1404 "info os shm" lists shared-memory regions
1405 "info os semaphores" lists semaphores
1406 "info os msg" lists message queues
1407 "info os modules" lists loaded kernel modules
1409 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1410 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1411 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1412 options and inspect the probe arguments using the new $_probe_arg family
1413 of convenience variables. You can obtain more information about SystemTap
1414 in <http://sourceware.org/systemtap/>.
1416 * GDB now supports reversible debugging on ARM, it allows you to
1417 debug basic ARM and THUMB instructions, and provides
1418 record/replay support.
1420 * The option "symbol-reloading" has been deleted as it is no longer used.
1424 ** GDB commands implemented in Python can now be put in command class
1427 ** The "maint set python print-stack on|off" is now deleted.
1429 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1430 apply "flag enum"-style pretty-printing to any enum.
1432 ** gdb.lookup_symbol can now work when there is no current frame.
1434 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1435 the source at which the symbol was defined.
1437 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1438 method 'value'. The former indicates whether the symbol needs a
1439 frame in order to compute its value, and the latter computes the
1442 ** A new method 'referenced_value' on gdb.Value objects which can
1443 dereference pointer as well as C++ reference values.
1445 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1446 which return the global and static blocks (as gdb.Block objects),
1447 of the underlying symbol table, respectively.
1449 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1450 object associated with a PC value.
1452 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1453 of the address range occupied by code for the current source line.
1455 * Go language support.
1456 GDB now supports debugging programs written in the Go programming
1459 * GDBserver now supports stdio connections.
1460 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1462 * The binary "gdbtui" can no longer be built or installed.
1463 Use "gdb -tui" instead.
1465 * GDB will now print "flag" enums specially. A flag enum is one where
1466 all the enumerator values have no bits in common when pairwise
1467 "and"ed. When printing a value whose type is a flag enum, GDB will
1468 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1469 (gdb) print (enum E) 3
1472 * The filename part of a linespec will now match trailing components
1473 of a source file name. For example, "break gcc/expr.c:1000" will
1474 now set a breakpoint in build/gcc/expr.c, but not
1475 build/libcpp/expr.c.
1477 * The "info proc" and "generate-core-file" commands will now also
1478 work on remote targets connected to GDBserver on Linux.
1480 * The command "info catch" has been removed. It has been disabled
1481 since December 2007.
1483 * The "catch exception" and "catch assert" commands now accept
1484 a condition at the end of the command, much like the "break"
1485 command does. For instance:
1487 (gdb) catch exception Constraint_Error if Barrier = True
1489 Previously, it was possible to add a condition to such catchpoints,
1490 but it had to be done as a second step, after the catchpoint had been
1491 created, using the "condition" command.
1493 * The "info static-tracepoint-marker" command will now also work on
1494 native Linux targets with in-process agent.
1496 * GDB can now set breakpoints on inlined functions.
1498 * The .gdb_index section has been updated to include symbols for
1499 inlined functions. GDB will ignore older .gdb_index sections by
1500 default, which could cause symbol files to be loaded more slowly
1501 until their .gdb_index sections can be recreated. The new command
1502 "set use-deprecated-index-sections on" will cause GDB to use any older
1503 .gdb_index sections it finds. This will restore performance, but the
1504 ability to set breakpoints on inlined functions will be lost in symbol
1505 files with older .gdb_index sections.
1507 The .gdb_index section has also been updated to record more information
1508 about each symbol. This speeds up the "info variables", "info functions"
1509 and "info types" commands when used with programs having the .gdb_index
1510 section, as well as speeding up debugging with shared libraries using
1511 the .gdb_index section.
1513 * Ada support for GDB/MI Variable Objects has been added.
1515 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1520 ** New command -info-os is the MI equivalent of "info os".
1522 ** Output logs ("set logging" and related) now include MI output.
1526 ** "set use-deprecated-index-sections on|off"
1527 "show use-deprecated-index-sections on|off"
1528 Controls the use of deprecated .gdb_index sections.
1530 ** "catch load" and "catch unload" can be used to stop when a shared
1531 library is loaded or unloaded, respectively.
1533 ** "enable count" can be used to auto-disable a breakpoint after
1536 ** "info vtbl" can be used to show the virtual method tables for
1537 C++ and Java objects.
1539 ** "explore" and its sub commands "explore value" and "explore type"
1540 can be used to recursively explore values and types of
1541 expressions. These commands are available only if GDB is
1542 configured with '--with-python'.
1544 ** "info auto-load" shows status of all kinds of auto-loaded files,
1545 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1546 sequences of commands files, "info auto-load python-scripts"
1547 shows status of auto-loading Python script files,
1548 "info auto-load local-gdbinit" shows status of loading init file
1549 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1550 status of inferior specific thread debugging shared library loading.
1552 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1553 and "show auto-load-scripts" commands have been deprecated, use their
1554 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1555 and "show auto-load python-scripts" counterparts instead.
1557 ** "dprintf location,format,args..." creates a dynamic printf, which
1558 is basically a breakpoint that does a printf and immediately
1559 resumes your program's execution, so it is like a printf that you
1560 can insert dynamically at runtime instead of at compiletime.
1562 ** "set print symbol"
1564 Controls whether GDB attempts to display the symbol, if any,
1565 corresponding to addresses it prints. This defaults to "on", but
1566 you can set it to "off" to restore GDB's previous behavior.
1568 * Deprecated commands
1570 ** For the Renesas Super-H architecture, the "regs" command has been
1571 deprecated, and "info all-registers" should be used instead.
1575 Renesas RL78 rl78-*-elf
1576 HP OpenVMS ia64 ia64-hp-openvms*
1578 * GDBserver supports evaluation of breakpoint conditions. When
1579 support is advertised by GDBserver, GDB may be told to send the
1580 breakpoint conditions in bytecode form to GDBserver. GDBserver
1581 will only report the breakpoint trigger to GDB when its condition
1586 set mips compression
1587 show mips compression
1588 Select the compressed ISA encoding used in functions that have no symbol
1589 information available. The encoding can be set to either of:
1592 and is updated automatically from ELF file flags if available.
1594 set breakpoint condition-evaluation
1595 show breakpoint condition-evaluation
1596 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1597 GDBserver ("target"). Default option "auto" chooses the most efficient
1599 This option can improve debugger efficiency depending on the speed of the
1603 Disable auto-loading globally.
1606 Show auto-loading setting of all kinds of auto-loaded files.
1608 set auto-load gdb-scripts on|off
1609 show auto-load gdb-scripts
1610 Control auto-loading of GDB canned sequences of commands files.
1612 set auto-load python-scripts on|off
1613 show auto-load python-scripts
1614 Control auto-loading of Python script files.
1616 set auto-load local-gdbinit on|off
1617 show auto-load local-gdbinit
1618 Control loading of init file (.gdbinit) from current directory.
1620 set auto-load libthread-db on|off
1621 show auto-load libthread-db
1622 Control auto-loading of inferior specific thread debugging shared library.
1624 set auto-load scripts-directory <dir1>[:<dir2>...]
1625 show auto-load scripts-directory
1626 Set a list of directories from which to load auto-loaded scripts.
1627 Automatically loaded Python scripts and GDB scripts are located in one
1628 of the directories listed by this option.
1629 The delimiter (':' above) may differ according to the host platform.
1631 set auto-load safe-path <dir1>[:<dir2>...]
1632 show auto-load safe-path
1633 Set a list of directories from which it is safe to auto-load files.
1634 The delimiter (':' above) may differ according to the host platform.
1636 set debug auto-load on|off
1637 show debug auto-load
1638 Control display of debugging info for auto-loading the files above.
1640 set dprintf-style gdb|call|agent
1642 Control the way in which a dynamic printf is performed; "gdb"
1643 requests a GDB printf command, while "call" causes dprintf to call a
1644 function in the inferior. "agent" requests that the target agent
1645 (such as GDBserver) do the printing.
1647 set dprintf-function <expr>
1648 show dprintf-function
1649 set dprintf-channel <expr>
1650 show dprintf-channel
1651 Set the function and optional first argument to the call when using
1652 the "call" style of dynamic printf.
1654 set disconnected-dprintf on|off
1655 show disconnected-dprintf
1656 Control whether agent-style dynamic printfs continue to be in effect
1657 after GDB disconnects.
1659 * New configure options
1661 --with-auto-load-dir
1662 Configure default value for the 'set auto-load scripts-directory'
1663 setting above. It defaults to '$debugdir:$datadir/auto-load',
1664 $debugdir representing global debugging info directories (available
1665 via 'show debug-file-directory') and $datadir representing GDB's data
1666 directory (available via 'show data-directory').
1668 --with-auto-load-safe-path
1669 Configure default value for the 'set auto-load safe-path' setting
1670 above. It defaults to the --with-auto-load-dir setting.
1672 --without-auto-load-safe-path
1673 Set 'set auto-load safe-path' to '/', effectively disabling this
1676 * New remote packets
1678 z0/z1 conditional breakpoints extension
1680 The z0/z1 breakpoint insertion packets have been extended to carry
1681 a list of conditional expressions over to the remote stub depending on the
1682 condition evaluation mode. The use of this extension can be controlled
1683 via the "set remote conditional-breakpoints-packet" command.
1687 Specify the signals which the remote stub may pass to the debugged
1688 program without GDB involvement.
1690 * New command line options
1692 --init-command=FILE, -ix Like --command, -x but execute it
1693 before loading inferior.
1694 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1695 execute it before loading inferior.
1697 *** Changes in GDB 7.4
1699 * GDB now handles ambiguous linespecs more consistently; the existing
1700 FILE:LINE support has been expanded to other types of linespecs. A
1701 breakpoint will now be set on all matching locations in all
1702 inferiors, and locations will be added or removed according to
1705 * GDB now allows you to skip uninteresting functions and files when
1706 stepping with the "skip function" and "skip file" commands.
1708 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1709 and "show remote hardware-watchpoint-length-limit". These allows to
1710 set or show the maximum length limit (in bytes) of a remote
1711 target hardware watchpoint.
1713 This allows e.g. to use "unlimited" hardware watchpoints with the
1714 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1715 watchpoints are slower than real hardware watchpoints but are
1716 significantly faster than gdb software watchpoints.
1720 ** The register_pretty_printer function in module gdb.printing now takes
1721 an optional `replace' argument. If True, the new printer replaces any
1724 ** The "maint set python print-stack on|off" command has been
1725 deprecated and will be deleted in GDB 7.5.
1726 A new command: "set python print-stack none|full|message" has
1727 replaced it. Additionally, the default for "print-stack" is
1728 now "message", which just prints the error message without
1731 ** A prompt substitution hook (prompt_hook) is now available to the
1734 ** A new Python module, gdb.prompt has been added to the GDB Python
1735 modules library. This module provides functionality for
1736 escape sequences in prompts (used by set/show
1737 extended-prompt). These escape sequences are replaced by their
1738 corresponding value.
1740 ** Python commands and convenience-functions located in
1741 'data-directory'/python/gdb/command and
1742 'data-directory'/python/gdb/function are now automatically loaded
1745 ** Blocks now provide four new attributes. global_block and
1746 static_block will return the global and static blocks
1747 respectively. is_static and is_global are boolean attributes
1748 that indicate if the block is one of those two types.
1750 ** Symbols now provide the "type" attribute, the type of the symbol.
1752 ** The "gdb.breakpoint" function has been deprecated in favor of
1755 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1756 of a function. This class is based on the "finish" command
1757 available in the CLI.
1759 ** Type objects for struct and union types now allow access to
1760 the fields using standard Python dictionary (mapping) methods.
1761 For example, "some_type['myfield']" now works, as does
1762 "some_type.items()".
1764 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1767 ** A new function, "deep_items" has been added to the gdb.types
1768 module in the GDB Python modules library. This function returns
1769 an iterator over the fields of a struct or union type. Unlike
1770 the standard Python "iteritems" method, it will recursively traverse
1771 any anonymous fields.
1775 ** "*stopped" events can report several new "reason"s, such as
1778 ** Breakpoint changes are now notified using new async records, like
1779 "=breakpoint-modified".
1781 ** New command -ada-task-info.
1783 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1784 $sdir specifies the default system locations of shared libraries.
1785 $pdir specifies the directory where the libpthread used by the application
1788 GDB no longer looks in $sdir and $pdir after it has searched the directories
1789 mentioned in libthread-db-search-path. If you want to search those
1790 directories, they must be specified in libthread-db-search-path.
1791 The default value of libthread-db-search-path on GNU/Linux and Solaris
1792 systems is now "$sdir:$pdir".
1794 $pdir is not supported by gdbserver, it is currently ignored.
1795 $sdir is supported by gdbserver.
1797 * New configure option --with-iconv-bin.
1798 When using the internationalization support like the one in the GNU C
1799 library, GDB will invoke the "iconv" program to get a list of supported
1800 character sets. If this program lives in a non-standard location, one can
1801 use this option to specify where to find it.
1803 * When natively debugging programs on PowerPC BookE processors running
1804 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1805 watchpoints, which specify a mask in addition to an address to watch.
1806 The mask specifies that some bits of an address (the bits which are
1807 reset in the mask) should be ignored when matching the address accessed
1808 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1809 section in the user manual for more details.
1811 * The new option --once causes GDBserver to stop listening for connections once
1812 the first connection is made. The listening port used by GDBserver will
1813 become available after that.
1815 * New commands "info macros" and "alias" have been added.
1817 * New function parameters suffix @entry specifies value of function parameter
1818 at the time the function got called. Entry values are available only since
1824 "!" is now an alias of the "shell" command.
1825 Note that no space is needed between "!" and SHELL COMMAND.
1829 watch EXPRESSION mask MASK_VALUE
1830 The watch command now supports the mask argument which allows creation
1831 of masked watchpoints, if the current architecture supports this feature.
1833 info auto-load-scripts [REGEXP]
1834 This command was formerly named "maintenance print section-scripts".
1835 It is now generally useful and is no longer a maintenance-only command.
1837 info macro [-all] [--] MACRO
1838 The info macro command has new options `-all' and `--'. The first for
1839 printing all definitions of a macro. The second for explicitly specifying
1840 the end of arguments and the beginning of the macro name in case the macro
1841 name starts with a hyphen.
1843 collect[/s] EXPRESSIONS
1844 The tracepoint collect command now takes an optional modifier "/s"
1845 that directs it to dereference pointer-to-character types and
1846 collect the bytes of memory up to a zero byte. The behavior is
1847 similar to what you see when you use the regular print command on a
1848 string. An optional integer following the "/s" sets a bound on the
1849 number of bytes that will be collected.
1852 The trace start command now interprets any supplied arguments as a
1853 note to be recorded with the trace run, with an effect similar to
1854 setting the variable trace-notes.
1857 The trace stop command now interprets any arguments as a note to be
1858 mentioned along with the tstatus report that the trace was stopped
1859 with a command. The effect is similar to setting the variable
1862 * Tracepoints can now be enabled and disabled at any time after a trace
1863 experiment has been started using the standard "enable" and "disable"
1864 commands. It is now possible to start a trace experiment with no enabled
1865 tracepoints; GDB will display a warning, but will allow the experiment to
1866 begin, assuming that tracepoints will be enabled as needed while the trace
1869 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1870 locations with 4-byte instructions, when they were previously
1871 limited to locations with instructions of 5 bytes or longer.
1875 set debug dwarf2-read
1876 show debug dwarf2-read
1877 Turns on or off display of debugging messages related to reading
1878 DWARF debug info. The default is off.
1880 set debug symtab-create
1881 show debug symtab-create
1882 Turns on or off display of debugging messages related to symbol table
1883 creation. The default is off.
1886 show extended-prompt
1887 Set the GDB prompt, and allow escape sequences to be inserted to
1888 display miscellaneous information (see 'help set extended-prompt'
1889 for the list of sequences). This prompt (and any information
1890 accessed through the escape sequences) is updated every time the
1891 prompt is displayed.
1893 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1894 show print entry-values
1895 Set printing of frame argument values at function entry. In some cases
1896 GDB can determine the value of function argument which was passed by the
1897 function caller, even if the value was modified inside the called function.
1899 set debug entry-values
1900 show debug entry-values
1901 Control display of debugging info for determining frame argument values at
1902 function entry and virtual tail call frames.
1904 set basenames-may-differ
1905 show basenames-may-differ
1906 Set whether a source file may have multiple base names.
1907 (A "base name" is the name of a file with the directory part removed.
1908 Example: The base name of "/home/user/hello.c" is "hello.c".)
1909 If set, GDB will canonicalize file names (e.g., expand symlinks)
1910 before comparing them. Canonicalization is an expensive operation,
1911 but it allows the same file be known by more than one base name.
1912 If not set (the default), all source files are assumed to have just
1913 one base name, and gdb will do file name comparisons more efficiently.
1919 Set a user name and notes for the current and any future trace runs.
1920 This is useful for long-running and/or disconnected traces, to
1921 inform others (or yourself) as to who is running the trace, supply
1922 contact information, or otherwise explain what is going on.
1924 set trace-stop-notes
1925 show trace-stop-notes
1926 Set a note attached to the trace run, that is displayed when the
1927 trace has been stopped by a tstop command. This is useful for
1928 instance as an explanation, if you are stopping a trace run that was
1929 started by someone else.
1931 * New remote packets
1935 Dynamically enable a tracepoint in a started trace experiment.
1939 Dynamically disable a tracepoint in a started trace experiment.
1943 Set the user and notes of the trace run.
1947 Query the current status of a tracepoint.
1951 Query the minimum length of instruction at which a fast tracepoint may
1954 * Dcache size (number of lines) and line-size are now runtime-configurable
1955 via "set dcache line" and "set dcache line-size" commands.
1959 Texas Instruments TMS320C6x tic6x-*-*
1963 Renesas RL78 rl78-*-elf
1965 *** Changes in GDB 7.3.1
1967 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1969 *** Changes in GDB 7.3
1971 * GDB has a new command: "thread find [REGEXP]".
1972 It finds the thread id whose name, target id, or thread extra info
1973 matches the given regular expression.
1975 * The "catch syscall" command now works on mips*-linux* targets.
1977 * The -data-disassemble MI command now supports modes 2 and 3 for
1978 dumping the instruction opcodes.
1980 * New command line options
1982 -data-directory DIR Specify DIR as the "data-directory".
1983 This is mostly for testing purposes.
1985 * The "maint set python auto-load on|off" command has been renamed to
1986 "set auto-load-scripts on|off".
1988 * GDB has a new command: "set directories".
1989 It is like the "dir" command except that it replaces the
1990 source path list instead of augmenting it.
1992 * GDB now understands thread names.
1994 On GNU/Linux, "info threads" will display the thread name as set by
1995 prctl or pthread_setname_np.
1997 There is also a new command, "thread name", which can be used to
1998 assign a name internally for GDB to display.
2001 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2002 has been integrated into GDB.
2006 ** The function gdb.Write now accepts an optional keyword 'stream'.
2007 This keyword, when provided, will direct the output to either
2008 stdout, stderr, or GDB's logging output.
2010 ** Parameters can now be be sub-classed in Python, and in particular
2011 you may implement the get_set_doc and get_show_doc functions.
2012 This improves how Parameter set/show documentation is processed
2013 and allows for more dynamic content.
2015 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2016 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2017 have an is_valid method.
2019 ** Breakpoints can now be sub-classed in Python, and in particular
2020 you may implement a 'stop' function that is executed each time
2021 the inferior reaches that breakpoint.
2023 ** New function gdb.lookup_global_symbol looks up a global symbol.
2025 ** GDB values in Python are now callable if the value represents a
2026 function. For example, if 'some_value' represents a function that
2027 takes two integer parameters and returns a value, you can call
2028 that function like so:
2030 result = some_value (10,20)
2032 ** Module gdb.types has been added.
2033 It contains a collection of utilities for working with gdb.Types objects:
2034 get_basic_type, has_field, make_enum_dict.
2036 ** Module gdb.printing has been added.
2037 It contains utilities for writing and registering pretty-printers.
2038 New classes: PrettyPrinter, SubPrettyPrinter,
2039 RegexpCollectionPrettyPrinter.
2040 New function: register_pretty_printer.
2042 ** New commands "info pretty-printers", "enable pretty-printer" and
2043 "disable pretty-printer" have been added.
2045 ** gdb.parameter("directories") is now available.
2047 ** New function gdb.newest_frame returns the newest frame in the
2050 ** The gdb.InferiorThread class has a new "name" attribute. This
2051 holds the thread's name.
2053 ** Python Support for Inferior events.
2054 Python scripts can add observers to be notified of events
2055 occurring in the process being debugged.
2056 The following events are currently supported:
2057 - gdb.events.cont Continue event.
2058 - gdb.events.exited Inferior exited event.
2059 - gdb.events.stop Signal received, and Breakpoint hit events.
2063 ** GDB now puts template parameters in scope when debugging in an
2064 instantiation. For example, if you have:
2066 template<int X> int func (void) { return X; }
2068 then if you step into func<5>, "print X" will show "5". This
2069 feature requires proper debuginfo support from the compiler; it
2070 was added to GCC 4.5.
2072 ** The motion commands "next", "finish", "until", and "advance" now
2073 work better when exceptions are thrown. In particular, GDB will
2074 no longer lose control of the inferior; instead, the GDB will
2075 stop the inferior at the point at which the exception is caught.
2076 This functionality requires a change in the exception handling
2077 code that was introduced in GCC 4.5.
2079 * GDB now follows GCC's rules on accessing volatile objects when
2080 reading or writing target state during expression evaluation.
2081 One notable difference to prior behavior is that "print x = 0"
2082 no longer generates a read of x; the value of the assignment is
2083 now always taken directly from the value being assigned.
2085 * GDB now has some support for using labels in the program's source in
2086 linespecs. For instance, you can use "advance label" to continue
2087 execution to a label.
2089 * GDB now has support for reading and writing a new .gdb_index
2090 section. This section holds a fast index of DWARF debugging
2091 information and can be used to greatly speed up GDB startup and
2092 operation. See the documentation for `save gdb-index' for details.
2094 * The "watch" command now accepts an optional "-location" argument.
2095 When used, this causes GDB to watch the memory referred to by the
2096 expression. Such a watchpoint is never deleted due to it going out
2099 * GDB now supports thread debugging of core dumps on GNU/Linux.
2101 GDB now activates thread debugging using the libthread_db library
2102 when debugging GNU/Linux core dumps, similarly to when debugging
2103 live processes. As a result, when debugging a core dump file, GDB
2104 is now able to display pthread_t ids of threads. For example, "info
2105 threads" shows the same output as when debugging the process when it
2106 was live. In earlier releases, you'd see something like this:
2109 * 1 LWP 6780 main () at main.c:10
2111 While now you see this:
2114 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2116 It is also now possible to inspect TLS variables when debugging core
2119 When debugging a core dump generated on a machine other than the one
2120 used to run GDB, you may need to point GDB at the correct
2121 libthread_db library with the "set libthread-db-search-path"
2122 command. See the user manual for more details on this command.
2124 * When natively debugging programs on PowerPC BookE processors running
2125 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2126 which stop execution of the inferior whenever it executes an instruction
2127 at any address within the specified range. See the "PowerPC Embedded"
2128 section in the user manual for more details.
2130 * New features in the GDB remote stub, GDBserver
2132 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2133 and i686 LynxOS (version 5.x).
2135 ** GDBserver is now supported on Blackfin Linux.
2137 * New native configurations
2139 ia64 HP-UX ia64-*-hpux*
2143 Analog Devices, Inc. Blackfin Processor bfin-*
2145 * Ada task switching is now supported on sparc-elf targets when
2146 debugging a program using the Ravenscar Profile. For more information,
2147 see the "Tasking Support when using the Ravenscar Profile" section
2148 in the GDB user manual.
2150 * Guile support was removed.
2152 * New features in the GNU simulator
2154 ** The --map-info flag lists all known core mappings.
2156 ** CFI flashes may be simulated via the "cfi" device.
2158 *** Changes in GDB 7.2
2160 * Shared library support for remote targets by default
2162 When GDB is configured for a generic, non-OS specific target, like
2163 for example, --target=arm-eabi or one of the many *-*-elf targets,
2164 GDB now queries remote stubs for loaded shared libraries using the
2165 `qXfer:libraries:read' packet. Previously, shared library support
2166 was always disabled for such configurations.
2170 ** Argument Dependent Lookup (ADL)
2172 In C++ ADL lookup directs function search to the namespaces of its
2173 arguments even if the namespace has not been imported.
2183 Here the compiler will search for `foo' in the namespace of 'b'
2184 and find A::foo. GDB now supports this. This construct is commonly
2185 used in the Standard Template Library for operators.
2187 ** Improved User Defined Operator Support
2189 In addition to member operators, GDB now supports lookup of operators
2190 defined in a namespace and imported with a `using' directive, operators
2191 defined in the global scope, operators imported implicitly from an
2192 anonymous namespace, and the ADL operators mentioned in the previous
2194 GDB now also supports proper overload resolution for all the previously
2195 mentioned flavors of operators.
2197 ** static const class members
2199 Printing of static const class members that are initialized in the
2200 class definition has been fixed.
2202 * Windows Thread Information Block access.
2204 On Windows targets, GDB now supports displaying the Windows Thread
2205 Information Block (TIB) structure. This structure is visible either
2206 by using the new command `info w32 thread-information-block' or, by
2207 dereferencing the new convenience variable named `$_tlb', a
2208 thread-specific pointer to the TIB. This feature is also supported
2209 when remote debugging using GDBserver.
2211 * Static tracepoints
2213 Static tracepoints are calls in the user program into a tracing
2214 library. One such library is a port of the LTTng kernel tracer to
2215 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2216 When debugging with GDBserver, GDB now supports combining the GDB
2217 tracepoint machinery with such libraries. For example: the user can
2218 use GDB to probe a static tracepoint marker (a call from the user
2219 program into the tracing library) with the new "strace" command (see
2220 "New commands" below). This creates a "static tracepoint" in the
2221 breakpoint list, that can be manipulated with the same feature set
2222 as fast and regular tracepoints. E.g., collect registers, local and
2223 global variables, collect trace state variables, and define
2224 tracepoint conditions. In addition, the user can collect extra
2225 static tracepoint marker specific data, by collecting the new
2226 $_sdata internal variable. When analyzing the trace buffer, you can
2227 inspect $_sdata like any other variable available to GDB. For more
2228 information, see the "Tracepoints" chapter in GDB user manual. New
2229 remote packets have been defined to support static tracepoints, see
2230 the "New remote packets" section below.
2232 * Better reconstruction of tracepoints after disconnected tracing
2234 GDB will attempt to download the original source form of tracepoint
2235 definitions when starting a trace run, and then will upload these
2236 upon reconnection to the target, resulting in a more accurate
2237 reconstruction of the tracepoints that are in use on the target.
2241 You can now exercise direct control over the ways that GDB can
2242 affect your program. For instance, you can disallow the setting of
2243 breakpoints, so that the program can run continuously (assuming
2244 non-stop mode). In addition, the "observer" variable is available
2245 to switch all of the different controls; in observer mode, GDB
2246 cannot affect the target's behavior at all, which is useful for
2247 tasks like diagnosing live systems in the field.
2249 * The new convenience variable $_thread holds the number of the
2252 * New remote packets
2256 Return the address of the Windows Thread Information Block of a given thread.
2260 In response to several of the tracepoint packets, the target may now
2261 also respond with a number of intermediate `qRelocInsn' request
2262 packets before the final result packet, to have GDB handle
2263 relocating an instruction to execute at a different address. This
2264 is particularly useful for stubs that support fast tracepoints. GDB
2265 reports support for this feature in the qSupported packet.
2269 List static tracepoint markers in the target program.
2273 List static tracepoint markers at a given address in the target
2276 qXfer:statictrace:read
2278 Read the static trace data collected (by a `collect $_sdata'
2279 tracepoint action). The remote stub reports support for this packet
2280 to gdb's qSupported query.
2284 Send the current settings of GDB's permission flags.
2288 Send part of the source (textual) form of a tracepoint definition,
2289 which includes location, conditional, and action list.
2291 * The source command now accepts a -s option to force searching for the
2292 script in the source search path even if the script name specifies
2295 * New features in the GDB remote stub, GDBserver
2297 - GDBserver now support tracepoints (including fast tracepoints, and
2298 static tracepoints). The feature is currently supported by the
2299 i386-linux and amd64-linux builds. See the "Tracepoints support
2300 in gdbserver" section in the manual for more information.
2302 GDBserver JIT compiles the tracepoint's conditional agent
2303 expression bytecode into native code whenever possible for low
2304 overhead dynamic tracepoints conditionals. For such tracepoints,
2305 an expression that examines program state is evaluated when the
2306 tracepoint is reached, in order to determine whether to capture
2307 trace data. If the condition is simple and false, processing the
2308 tracepoint finishes very quickly and no data is gathered.
2310 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2311 for static tracepoints support.
2313 - GDBserver now supports x86_64 Windows 64-bit debugging.
2315 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2316 it understands register description.
2318 * The --batch flag now disables pagination and queries.
2320 * X86 general purpose registers
2322 GDB now supports reading/writing byte, word and double-word x86
2323 general purpose registers directly. This means you can use, say,
2324 $ah or $ax to refer, respectively, to the byte register AH and
2325 16-bit word register AX that are actually portions of the 32-bit
2326 register EAX or 64-bit register RAX.
2328 * The `commands' command now accepts a range of breakpoints to modify.
2329 A plain `commands' following a command that creates multiple
2330 breakpoints affects all the breakpoints set by that command. This
2331 applies to breakpoints set by `rbreak', and also applies when a
2332 single `break' command creates multiple breakpoints (e.g.,
2333 breakpoints on overloaded c++ functions).
2335 * The `rbreak' command now accepts a filename specification as part of
2336 its argument, limiting the functions selected by the regex to those
2337 in the specified file.
2339 * Support for remote debugging Windows and SymbianOS shared libraries
2340 from Unix hosts has been improved. Non Windows GDB builds now can
2341 understand target reported file names that follow MS-DOS based file
2342 system semantics, such as file names that include drive letters and
2343 use the backslash character as directory separator. This makes it
2344 possible to transparently use the "set sysroot" and "set
2345 solib-search-path" on Unix hosts to point as host copies of the
2346 target's shared libraries. See the new command "set
2347 target-file-system-kind" described below, and the "Commands to
2348 specify files" section in the user manual for more information.
2352 eval template, expressions...
2353 Convert the values of one or more expressions under the control
2354 of the string template to a command line, and call it.
2356 set target-file-system-kind unix|dos-based|auto
2357 show target-file-system-kind
2358 Set or show the assumed file system kind for target reported file
2361 save breakpoints <filename>
2362 Save all current breakpoint definitions to a file suitable for use
2363 in a later debugging session. To read the saved breakpoint
2364 definitions, use the `source' command.
2366 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2369 info static-tracepoint-markers
2370 Display information about static tracepoint markers in the target.
2372 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2373 Define a static tracepoint by probing a marker at the given
2374 function, line, address, or marker ID.
2378 Enable and disable observer mode.
2380 set may-write-registers on|off
2381 set may-write-memory on|off
2382 set may-insert-breakpoints on|off
2383 set may-insert-tracepoints on|off
2384 set may-insert-fast-tracepoints on|off
2385 set may-interrupt on|off
2386 Set individual permissions for GDB effects on the target. Note that
2387 some of these settings can have undesirable or surprising
2388 consequences, particularly when changed in the middle of a session.
2389 For instance, disabling the writing of memory can prevent
2390 breakpoints from being inserted, cause single-stepping to fail, or
2391 even crash your program, if you disable after breakpoints have been
2392 inserted. However, GDB should not crash.
2394 set record memory-query on|off
2395 show record memory-query
2396 Control whether to stop the inferior if memory changes caused
2397 by an instruction cannot be recorded.
2402 The disassemble command now supports "start,+length" form of two arguments.
2406 ** GDB now provides a new directory location, called the python directory,
2407 where Python scripts written for GDB can be installed. The location
2408 of that directory is <data-directory>/python, where <data-directory>
2409 is the GDB data directory. For more details, see section `Scripting
2410 GDB using Python' in the manual.
2412 ** The GDB Python API now has access to breakpoints, symbols, symbol
2413 tables, program spaces, inferiors, threads and frame's code blocks.
2414 Additionally, GDB Parameters can now be created from the API, and
2415 manipulated via set/show in the CLI.
2417 ** New functions gdb.target_charset, gdb.target_wide_charset,
2418 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2420 ** New exception gdb.GdbError.
2422 ** Pretty-printers are now also looked up in the current program space.
2424 ** Pretty-printers can now be individually enabled and disabled.
2426 ** GDB now looks for names of Python scripts to auto-load in a
2427 special section named `.debug_gdb_scripts', in addition to looking
2428 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2430 * Tracepoint actions were unified with breakpoint commands. In particular,
2431 there are no longer differences in "info break" output for breakpoints and
2432 tracepoints and the "commands" command can be used for both tracepoints and
2433 regular breakpoints.
2437 ARM Symbian arm*-*-symbianelf*
2439 * D language support.
2440 GDB now supports debugging programs written in the D programming
2443 * GDB now supports the extended ptrace interface for PowerPC which is
2444 available since Linux kernel version 2.6.34. This automatically enables
2445 any hardware breakpoints and additional hardware watchpoints available in
2446 the processor. The old ptrace interface exposes just one hardware
2447 watchpoint and no hardware breakpoints.
2449 * GDB is now able to use the Data Value Compare (DVC) register available on
2450 embedded PowerPC processors to implement in hardware simple watchpoint
2451 conditions of the form:
2453 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2455 This works in native GDB running on Linux kernels with the extended ptrace
2456 interface mentioned above.
2458 *** Changes in GDB 7.1
2462 ** Namespace Support
2464 GDB now supports importing of namespaces in C++. This enables the
2465 user to inspect variables from imported namespaces. Support for
2466 namepace aliasing has also been added. So, if a namespace is
2467 aliased in the current scope (e.g. namepace C=A; ) the user can
2468 print variables using the alias (e.g. (gdb) print C::x).
2472 All known bugs relating to the printing of virtual base class were
2473 fixed. It is now possible to call overloaded static methods using a
2478 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2479 and reinterpret_cast<> are now handled by the C++ expression parser.
2483 Xilinx MicroBlaze microblaze-*-*
2488 Xilinx MicroBlaze microblaze
2491 * Multi-program debugging.
2493 GDB now has support for multi-program (a.k.a. multi-executable or
2494 multi-exec) debugging. This allows for debugging multiple inferiors
2495 simultaneously each running a different program under the same GDB
2496 session. See "Debugging Multiple Inferiors and Programs" in the
2497 manual for more information. This implied some user visible changes
2498 in the multi-inferior support. For example, "info inferiors" now
2499 lists inferiors that are not running yet or that have exited
2500 already. See also "New commands" and "New options" below.
2502 * New tracing features
2504 GDB's tracepoint facility now includes several new features:
2506 ** Trace state variables
2508 GDB tracepoints now include support for trace state variables, which
2509 are variables managed by the target agent during a tracing
2510 experiment. They are useful for tracepoints that trigger each
2511 other, so for instance one tracepoint can count hits in a variable,
2512 and then a second tracepoint has a condition that is true when the
2513 count reaches a particular value. Trace state variables share the
2514 $-syntax of GDB convenience variables, and can appear in both
2515 tracepoint actions and condition expressions. Use the "tvariable"
2516 command to create, and "info tvariables" to view; see "Trace State
2517 Variables" in the manual for more detail.
2521 GDB now includes an option for defining fast tracepoints, which
2522 targets may implement more efficiently, such as by installing a jump
2523 into the target agent rather than a trap instruction. The resulting
2524 speedup can be by two orders of magnitude or more, although the
2525 tradeoff is that some program locations on some target architectures
2526 might not allow fast tracepoint installation, for instance if the
2527 instruction to be replaced is shorter than the jump. To request a
2528 fast tracepoint, use the "ftrace" command, with syntax identical to
2529 the regular trace command.
2531 ** Disconnected tracing
2533 It is now possible to detach GDB from the target while it is running
2534 a trace experiment, then reconnect later to see how the experiment
2535 is going. In addition, a new variable disconnected-tracing lets you
2536 tell the target agent whether to continue running a trace if the
2537 connection is lost unexpectedly.
2541 GDB now has the ability to save the trace buffer into a file, and
2542 then use that file as a target, similarly to you can do with
2543 corefiles. You can select trace frames, print data that was
2544 collected in them, and use tstatus to display the state of the
2545 tracing run at the moment that it was saved. To create a trace
2546 file, use "tsave <filename>", and to use it, do "target tfile
2549 ** Circular trace buffer
2551 You can ask the target agent to handle the trace buffer as a
2552 circular buffer, discarding the oldest trace frames to make room for
2553 newer ones, by setting circular-trace-buffer to on. This feature may
2554 not be available for all target agents.
2559 The disassemble command, when invoked with two arguments, now requires
2560 the arguments to be comma-separated.
2563 The info variables command now displays variable definitions. Files
2564 which only declare a variable are not shown.
2567 The source command is now capable of sourcing Python scripts.
2568 This feature is dependent on the debugger being build with Python
2571 Related to this enhancement is also the introduction of a new command
2572 "set script-extension" (see below).
2574 * New commands (for set/show, see "New options" below)
2576 record save [<FILENAME>]
2577 Save a file (in core file format) containing the process record
2578 execution log for replay debugging at a later time.
2580 record restore <FILENAME>
2581 Restore the process record execution log that was saved at an
2582 earlier time, for replay debugging.
2584 add-inferior [-copies <N>] [-exec <FILENAME>]
2587 clone-inferior [-copies <N>] [ID]
2588 Make a new inferior ready to execute the same program another
2589 inferior has loaded.
2594 maint info program-spaces
2595 List the program spaces loaded into GDB.
2597 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2598 show remote interrupt-sequence
2599 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2600 as the sequence to the remote target in order to interrupt the execution.
2601 Ctrl-C is a default. Some system prefers BREAK which is high level of
2602 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2603 Magic SysRq g. It is BREAK signal and character 'g'.
2605 set remote interrupt-on-connect [on | off]
2606 show remote interrupt-on-connect
2607 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2608 remote target when gdb connects to it. This is needed when you debug
2611 set remotebreak [on | off]
2613 Deprecated. Use "set/show remote interrupt-sequence" instead.
2615 tvariable $NAME [ = EXP ]
2616 Create or modify a trace state variable.
2619 List trace state variables and their values.
2621 delete tvariable $NAME ...
2622 Delete one or more trace state variables.
2625 Evaluate the given expressions without collecting anything into the
2626 trace buffer. (Valid in tracepoint actions only.)
2628 ftrace FN / FILE:LINE / *ADDR
2629 Define a fast tracepoint at the given function, line, or address.
2631 * New expression syntax
2633 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2634 GDB now parses 0b101010 identically with 42.
2638 set follow-exec-mode new|same
2639 show follow-exec-mode
2640 Control whether GDB reuses the same inferior across an exec call or
2641 creates a new one. This is useful to be able to restart the old
2642 executable after the inferior having done an exec call.
2644 set default-collect EXPR, ...
2645 show default-collect
2646 Define a list of expressions to be collected at each tracepoint.
2647 This is a useful way to ensure essential items are not overlooked,
2648 such as registers or a critical global variable.
2650 set disconnected-tracing
2651 show disconnected-tracing
2652 If set to 1, the target is instructed to continue tracing if it
2653 loses its connection to GDB. If 0, the target is to stop tracing
2656 set circular-trace-buffer
2657 show circular-trace-buffer
2658 If set to on, the target is instructed to use a circular trace buffer
2659 and discard the oldest trace frames instead of stopping the trace due
2660 to a full trace buffer. If set to off, the trace stops when the buffer
2661 fills up. Some targets may not support this.
2663 set script-extension off|soft|strict
2664 show script-extension
2665 If set to "off", the debugger does not perform any script language
2666 recognition, and all sourced files are assumed to be GDB scripts.
2667 If set to "soft" (the default), files are sourced according to
2668 filename extension, falling back to GDB scripts if the first
2670 If set to "strict", files are sourced according to filename extension.
2672 set ada trust-PAD-over-XVS on|off
2673 show ada trust-PAD-over-XVS
2674 If off, activate a workaround against a bug in the debugging information
2675 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2676 the GCC sources for more information about the GNAT encoding and
2677 PAD types in particular). It is always safe to set this option to
2678 off, but this introduces a slight performance penalty. The default
2681 * Python API Improvements
2683 ** GDB provides the new class gdb.LazyString. This is useful in
2684 some pretty-printing cases. The new method gdb.Value.lazy_string
2685 provides a simple way to create objects of this type.
2687 ** The fields returned by gdb.Type.fields now have an
2688 `is_base_class' attribute.
2690 ** The new method gdb.Type.range returns the range of an array type.
2692 ** The new method gdb.parse_and_eval can be used to parse and
2693 evaluate an expression.
2695 * New remote packets
2698 Define a trace state variable.
2701 Get the current value of a trace state variable.
2704 Set desired tracing behavior upon disconnection.
2707 Set the trace buffer to be linear or circular.
2710 Get data about the tracepoints currently in use.
2714 Process record now works correctly with hardware watchpoints.
2716 Multiple bug fixes have been made to the mips-irix port, making it
2717 much more reliable. In particular:
2718 - Debugging threaded applications is now possible again. Previously,
2719 GDB would hang while starting the program, or while waiting for
2720 the program to stop at a breakpoint.
2721 - Attaching to a running process no longer hangs.
2722 - An error occurring while loading a core file has been fixed.
2723 - Changing the value of the PC register now works again. This fixes
2724 problems observed when using the "jump" command, or when calling
2725 a function from GDB, or even when assigning a new value to $pc.
2726 - With the "finish" and "return" commands, the return value for functions
2727 returning a small array is now correctly printed.
2728 - It is now possible to break on shared library code which gets executed
2729 during a shared library init phase (code executed while executing
2730 their .init section). Previously, the breakpoint would have no effect.
2731 - GDB is now able to backtrace through the signal handler for
2732 non-threaded programs.
2734 PIE (Position Independent Executable) programs debugging is now supported.
2735 This includes debugging execution of PIC (Position Independent Code) shared
2736 libraries although for that, it should be possible to run such libraries as an
2739 *** Changes in GDB 7.0
2741 * GDB now has an interface for JIT compilation. Applications that
2742 dynamically generate code can create symbol files in memory and register
2743 them with GDB. For users, the feature should work transparently, and
2744 for JIT developers, the interface is documented in the GDB manual in the
2745 "JIT Compilation Interface" chapter.
2747 * Tracepoints may now be conditional. The syntax is as for
2748 breakpoints; either an "if" clause appended to the "trace" command,
2749 or the "condition" command is available. GDB sends the condition to
2750 the target for evaluation using the same bytecode format as is used
2751 for tracepoint actions.
2753 * The disassemble command now supports: an optional /r modifier, print the
2754 raw instructions in hex as well as in symbolic form, and an optional /m
2755 modifier to print mixed source+assembly.
2757 * Process record and replay
2759 In a architecture environment that supports ``process record and
2760 replay'', ``process record and replay'' target can record a log of
2761 the process execution, and replay it with both forward and reverse
2764 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2765 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2766 set execution-direction {forward|reverse}, for targets that support
2769 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2770 feature is available with a native GDB running on kernel version
2773 * GDB now has support for multi-byte and wide character sets on the
2774 target. Strings whose character type is wchar_t, char16_t, or
2775 char32_t are now correctly printed. GDB supports wide- and unicode-
2776 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2777 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2778 `printf'. This feature requires iconv to work properly; if your
2779 system does not have a working iconv, GDB can use GNU libiconv. See
2780 the installation instructions for more information.
2782 * GDB now supports automatic retrieval of shared library files from
2783 remote targets. To use this feature, specify a system root that begins
2784 with the `remote:' prefix, either via the `set sysroot' command or via
2785 the `--with-sysroot' configure-time option.
2787 * "info sharedlibrary" now takes an optional regex of libraries to show,
2788 and it now reports if a shared library has no debugging information.
2790 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2791 now complete on file names.
2793 * When completing in expressions, gdb will attempt to limit
2794 completions to allowable structure or union fields, where appropriate.
2795 For instance, consider:
2797 # struct example { int f1; double f2; };
2798 # struct example variable;
2801 If the user types TAB at the end of this command line, the available
2802 completions will be "f1" and "f2".
2804 * Inlined functions are now supported. They show up in backtraces, and
2805 the "step", "next", and "finish" commands handle them automatically.
2807 * GDB now supports the token-splicing (##) and stringification (#)
2808 operators when expanding macros. It also supports variable-arity
2811 * GDB now supports inspecting extra signal information, exported by
2812 the new $_siginfo convenience variable. The feature is currently
2813 implemented on linux ARM, i386 and amd64.
2815 * GDB can now display the VFP floating point registers and NEON vector
2816 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2817 can provide these registers (requires Linux 2.6.30 or later). Remote
2818 and simulator targets may also provide them.
2820 * New remote packets
2823 Search memory for a sequence of bytes.
2826 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2827 operation over reliable transport links. Use of this packet is
2828 controlled by the `set remote noack-packet' command.
2831 Kill the process with the specified process ID. Use this in preference
2832 to `k' when multiprocess protocol extensions are supported.
2835 Obtains additional operating system information
2839 Read or write additional signal information.
2841 * Removed remote protocol undocumented extension
2843 An undocumented extension to the remote protocol's `S' stop reply
2844 packet that permited the stub to pass a process id was removed.
2845 Remote servers should use the `T' stop reply packet instead.
2847 * GDB now supports multiple function calling conventions according to the
2848 DWARF-2 DW_AT_calling_convention function attribute.
2850 * The SH target utilizes the aforementioned change to distinguish between gcc
2851 and Renesas calling convention. It also adds the new CLI commands
2852 `set/show sh calling-convention'.
2854 * GDB can now read compressed debug sections, as produced by GNU gold
2855 with the --compress-debug-sections=zlib flag.
2857 * 64-bit core files are now supported on AIX.
2859 * Thread switching is now supported on Tru64.
2861 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2862 which will be allocated using malloc later in program execution.
2864 * The qXfer:libraries:read remote procotol packet now allows passing a
2865 list of section offsets.
2867 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2868 conditions handling signals delivered during attach or thread creation
2869 have also been fixed.
2871 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2872 From the user's standpoint, all unqualified instances of True and False
2873 are treated as the standard definitions, regardless of context.
2875 * GDB now parses C++ symbol and type names more flexibly. For
2878 template<typename T> class C { };
2881 GDB will now correctly handle all of:
2883 ptype C<char const *>
2884 ptype C<char const*>
2885 ptype C<const char *>
2886 ptype C<const char*>
2888 * New features in the GDB remote stub, gdbserver
2890 - The "--wrapper" command-line argument tells gdbserver to use a
2891 wrapper program to launch programs for debugging.
2893 - On PowerPC and S/390 targets, it is now possible to use a single
2894 gdbserver executable to debug both 32-bit and 64-bit programs.
2895 (This requires gdbserver itself to be built as a 64-bit executable.)
2897 - gdbserver uses the new noack protocol mode for TCP connections to
2898 reduce communications latency, if also supported and enabled in GDB.
2900 - Support for the sparc64-linux-gnu target is now included in
2903 - The amd64-linux build of gdbserver now supports debugging both
2904 32-bit and 64-bit programs.
2906 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2907 now support hardware watchpoints, and will use them automatically
2912 GDB now has support for scripting using Python. Whether this is
2913 available is determined at configure time.
2915 New GDB commands can now be written in Python.
2917 * Ada tasking support
2919 Ada tasks can now be inspected in GDB. The following commands have
2923 Print the list of Ada tasks.
2925 Print detailed information about task number N.
2927 Print the task number of the current task.
2929 Switch the context of debugging to task number N.
2931 * Support for user-defined prefixed commands. The "define" command can
2932 add new commands to existing prefixes, e.g. "target".
2934 * Multi-inferior, multi-process debugging.
2936 GDB now has generalized support for multi-inferior debugging. See
2937 "Debugging Multiple Inferiors" in the manual for more information.
2938 Although availability still depends on target support, the command
2939 set is more uniform now. The GNU/Linux specific multi-forks support
2940 has been migrated to this new framework. This implied some user
2941 visible changes; see "New commands" and also "Removed commands"
2944 * Target descriptions can now describe the target OS ABI. See the
2945 "Target Description Format" section in the user manual for more
2948 * Target descriptions can now describe "compatible" architectures
2949 to indicate that the target can execute applications for a different
2950 architecture in addition to those for the main target architecture.
2951 See the "Target Description Format" section in the user manual for
2954 * Multi-architecture debugging.
2956 GDB now includes general supports for debugging applications on
2957 hybrid systems that use more than one single processor architecture
2958 at the same time. Each such hybrid architecture still requires
2959 specific support to be added. The only hybrid architecture supported
2960 in this version of GDB is the Cell Broadband Engine.
2962 * GDB now supports integrated debugging of Cell/B.E. applications that
2963 use both the PPU and SPU architectures. To enable support for hybrid
2964 Cell/B.E. debugging, you need to configure GDB to support both the
2965 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2966 --enable-targets configure option.
2968 * Non-stop mode debugging.
2970 For some targets, GDB now supports an optional mode of operation in
2971 which you can examine stopped threads while other threads continue
2972 to execute freely. This is referred to as non-stop mode, with the
2973 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2974 section in the user manual for more information.
2976 To be able to support remote non-stop debugging, a remote stub needs
2977 to implement the non-stop mode remote protocol extensions, as
2978 described in the "Remote Non-Stop" section of the user manual. The
2979 GDB remote stub, gdbserver, has been adjusted to support these
2980 extensions on linux targets.
2982 * New commands (for set/show, see "New options" below)
2984 catch syscall [NAME(S) | NUMBER(S)]
2985 Catch system calls. Arguments, which should be names of system
2986 calls or their numbers, mean catch only those syscalls. Without
2987 arguments, every syscall will be caught. When the inferior issues
2988 any of the specified syscalls, GDB will stop and announce the system
2989 call, both when it is called and when its call returns. This
2990 feature is currently available with a native GDB running on the
2991 Linux Kernel, under the following architectures: x86, x86_64,
2992 PowerPC and PowerPC64.
2994 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2996 Search memory for a sequence of bytes.
2998 maint set python print-stack
2999 maint show python print-stack
3000 Show a stack trace when an error is encountered in a Python script.
3003 Invoke CODE by passing it to the Python interpreter.
3008 These allow macros to be defined, undefined, and listed
3012 Show operating system information about processes.
3015 List the inferiors currently under GDB's control.
3018 Switch focus to inferior number NUM.
3021 Detach from inferior number NUM.
3024 Kill inferior number NUM.
3028 set spu stop-on-load
3029 show spu stop-on-load
3030 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3032 set spu auto-flush-cache
3033 show spu auto-flush-cache
3034 Control whether to automatically flush the software-managed cache
3035 during Cell/B.E. debugging.
3037 set sh calling-convention
3038 show sh calling-convention
3039 Control the calling convention used when calling SH target functions.
3042 show debug timestamp
3043 Control display of timestamps with GDB debugging output.
3045 set disassemble-next-line
3046 show disassemble-next-line
3047 Control display of disassembled source lines or instructions when
3050 set remote noack-packet
3051 show remote noack-packet
3052 Set/show the use of remote protocol QStartNoAckMode packet. See above
3053 under "New remote packets."
3055 set remote query-attached-packet
3056 show remote query-attached-packet
3057 Control use of remote protocol `qAttached' (query-attached) packet.
3059 set remote read-siginfo-object
3060 show remote read-siginfo-object
3061 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3064 set remote write-siginfo-object
3065 show remote write-siginfo-object
3066 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3069 set remote reverse-continue
3070 show remote reverse-continue
3071 Control use of remote protocol 'bc' (reverse-continue) packet.
3073 set remote reverse-step
3074 show remote reverse-step
3075 Control use of remote protocol 'bs' (reverse-step) packet.
3077 set displaced-stepping
3078 show displaced-stepping
3079 Control displaced stepping mode. Displaced stepping is a way to
3080 single-step over breakpoints without removing them from the debuggee.
3081 Also known as "out-of-line single-stepping".
3084 show debug displaced
3085 Control display of debugging info for displaced stepping.
3087 maint set internal-error
3088 maint show internal-error
3089 Control what GDB does when an internal error is detected.
3091 maint set internal-warning
3092 maint show internal-warning
3093 Control what GDB does when an internal warning is detected.
3098 Use a wrapper program to launch programs for debugging.
3100 set multiple-symbols (all|ask|cancel)
3101 show multiple-symbols
3102 The value of this variable can be changed to adjust the debugger behavior
3103 when an expression or a breakpoint location contains an ambiguous symbol
3104 name (an overloaded function name, for instance).
3106 set breakpoint always-inserted
3107 show breakpoint always-inserted
3108 Keep breakpoints always inserted in the target, as opposed to inserting
3109 them when resuming the target, and removing them when the target stops.
3110 This option can improve debugger performance on slow remote targets.
3112 set arm fallback-mode (arm|thumb|auto)
3113 show arm fallback-mode
3114 set arm force-mode (arm|thumb|auto)
3116 These commands control how ARM GDB determines whether instructions
3117 are ARM or Thumb. The default for both settings is auto, which uses
3118 the current CPSR value for instructions without symbols; previous
3119 versions of GDB behaved as if "set arm fallback-mode arm".
3121 set disable-randomization
3122 show disable-randomization
3123 Standalone programs run with the virtual address space randomization enabled
3124 by default on some platforms. This option keeps the addresses stable across
3125 multiple debugging sessions.
3129 Control whether other threads are stopped or not when some thread hits
3134 Requests that asynchronous execution is enabled in the target, if available.
3135 In this case, it's possible to resume target in the background, and interact
3136 with GDB while the target is running. "show target-async" displays the
3137 current state of asynchronous execution of the target.
3139 set target-wide-charset
3140 show target-wide-charset
3141 The target-wide-charset is the name of the character set that GDB
3142 uses when printing characters whose type is wchar_t.
3144 set tcp auto-retry (on|off)
3146 set tcp connect-timeout
3147 show tcp connect-timeout
3148 These commands allow GDB to retry failed TCP connections to a remote stub
3149 with a specified timeout period; this is useful if the stub is launched
3150 in parallel with GDB but may not be ready to accept connections immediately.
3152 set libthread-db-search-path
3153 show libthread-db-search-path
3154 Control list of directories which GDB will search for appropriate
3157 set schedule-multiple (on|off)
3158 show schedule-multiple
3159 Allow GDB to resume all threads of all processes or only threads of
3160 the current process.
3164 Use more aggressive caching for accesses to the stack. This improves
3165 performance of remote debugging (particularly backtraces) without
3166 affecting correctness.
3168 set interactive-mode (on|off|auto)
3169 show interactive-mode
3170 Control whether GDB runs in interactive mode (on) or not (off).
3171 When in interactive mode, GDB waits for the user to answer all
3172 queries. Otherwise, GDB does not wait and assumes the default
3173 answer. When set to auto (the default), GDB determines which
3174 mode to use based on the stdin settings.
3179 For program forks, this is replaced by the new more generic `info
3180 inferiors' command. To list checkpoints, you can still use the
3181 `info checkpoints' command, which was an alias for the `info forks'
3185 Replaced by the new `inferior' command. To switch between
3186 checkpoints, you can still use the `restart' command, which was an
3187 alias for the `fork' command.
3190 This is removed, since some targets don't have a notion of
3191 processes. To switch between processes, you can still use the
3192 `inferior' command using GDB's own inferior number.
3195 For program forks, this is replaced by the new more generic `kill
3196 inferior' command. To delete a checkpoint, you can still use the
3197 `delete checkpoint' command, which was an alias for the `delete
3201 For program forks, this is replaced by the new more generic `detach
3202 inferior' command. To detach a checkpoint, you can still use the
3203 `detach checkpoint' command, which was an alias for the `detach
3206 * New native configurations
3208 x86/x86_64 Darwin i[34567]86-*-darwin*
3210 x86_64 MinGW x86_64-*-mingw*
3214 Lattice Mico32 lm32-*
3215 x86 DICOS i[34567]86-*-dicos*
3216 x86_64 DICOS x86_64-*-dicos*
3219 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3220 (mingw32ce) debugging.
3226 These commands were actually not implemented on any target.
3228 *** Changes in GDB 6.8
3230 * New native configurations
3232 NetBSD/hppa hppa*-*netbsd*
3233 Xtensa GNU/Linux xtensa*-*-linux*
3237 NetBSD/hppa hppa*-*-netbsd*
3238 Xtensa GNU/Lunux xtensa*-*-linux*
3240 * Change in command line behavior -- corefiles vs. process ids.
3242 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3243 attaching to process NUMBER fails, GDB no longer attempts to open a
3244 core file named NUMBER. Attaching to a program using the -c option
3245 is no longer supported. Instead, use the '-p' or '--pid' options.
3247 * GDB can now be built as a native debugger for debugging Windows x86
3248 (mingw32) Portable Executable (PE) programs.
3250 * Pending breakpoints no longer change their number when their address
3253 * GDB now supports breakpoints with multiple locations,
3254 including breakpoints on C++ constructors, inside C++ templates,
3255 and in inlined functions.
3257 * GDB's ability to debug optimized code has been improved. GDB more
3258 accurately identifies function bodies and lexical blocks that occupy
3259 more than one contiguous range of addresses.
3261 * Target descriptions can now describe registers for PowerPC.
3263 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3264 registers on PowerPC targets.
3266 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3267 targets even when the libthread_db library is not available.
3269 * The GDB remote stub, gdbserver, now supports the new file transfer
3270 commands (remote put, remote get, and remote delete).
3272 * The GDB remote stub, gdbserver, now supports run and attach in
3273 extended-remote mode.
3275 * hppa*64*-*-hpux11* target broken
3276 The debugger is unable to start a program and fails with the following
3277 error: "Error trying to get information about dynamic linker".
3278 The gdb-6.7 release is also affected.
3280 * GDB now supports the --enable-targets= configure option to allow
3281 building a single GDB executable that supports multiple remote
3282 target architectures.
3284 * GDB now supports debugging C and C++ programs which use the
3285 Decimal Floating Point extension. In addition, the PowerPC target
3286 now has a set of pseudo-registers to inspect decimal float values
3287 stored in two consecutive float registers.
3289 * The -break-insert MI command can optionally create pending
3292 * Improved support for debugging Ada
3293 Many improvements to the Ada language support have been made. These
3295 - Better support for Ada2005 interface types
3296 - Improved handling of arrays and slices in general
3297 - Better support for Taft-amendment types
3298 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3300 - Improved command completion in Ada
3303 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3308 set print frame-arguments (all|scalars|none)
3309 show print frame-arguments
3310 The value of this variable can be changed to control which argument
3311 values should be printed by the debugger when displaying a frame.
3316 Transfer files to and from a remote target, and delete remote files.
3323 Transfer files to and from a remote target, and delete remote files.
3325 * New remote packets
3332 Open, close, read, write, and delete files on the remote system.
3335 Attach to an existing process on the remote system, in extended-remote
3339 Run a new process on the remote system, in extended-remote mode.
3341 *** Changes in GDB 6.7
3343 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3344 bfd, libiberty and opcodes, as revealed by static analysis donated by
3345 Coverity, Inc. (http://scan.coverity.com).
3347 * When looking up multiply-defined global symbols, GDB will now prefer the
3348 symbol definition in the current shared library if it was built using the
3349 -Bsymbolic linker option.
3351 * When the Text User Interface (TUI) is not configured, GDB will now
3352 recognize the -tui command-line option and print a message that the TUI
3355 * The GDB remote stub, gdbserver, now has lower overhead for high
3356 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3358 * GDB for MIPS targets now autodetects whether a remote target provides
3359 32-bit or 64-bit register values.
3361 * Support for C++ member pointers has been improved.
3363 * GDB now understands XML target descriptions, which specify the
3364 target's overall architecture. GDB can read a description from
3365 a local file or over the remote serial protocol.
3367 * Vectors of single-byte data use a new integer type which is not
3368 automatically displayed as character or string data.
3370 * The /s format now works with the print command. It displays
3371 arrays of single-byte integers and pointers to single-byte integers
3374 * Target descriptions can now describe target-specific registers,
3375 for architectures which have implemented the support (currently
3376 only ARM, M68K, and MIPS).
3378 * GDB and the GDB remote stub, gdbserver, now support the XScale
3381 * The GDB remote stub, gdbserver, has been updated to support
3382 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3383 has been rewritten to use the standard GDB remote protocol.
3385 * GDB can now step into C++ functions which are called through thunks.
3387 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3389 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3390 layout. It also supports a TextSeg= and DataSeg= response when only
3391 segment base addresses (rather than offsets) are available.
3393 * The /i format now outputs any trailing branch delay slot instructions
3394 immediately following the last instruction within the count specified.
3396 * The GDB remote protocol "T" stop reply packet now supports a
3397 "library" response. Combined with the new "qXfer:libraries:read"
3398 packet, this response allows GDB to debug shared libraries on targets
3399 where the operating system manages the list of loaded libraries (e.g.
3400 Windows and SymbianOS).
3402 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3403 (DLLs) on Windows and Windows CE targets.
3405 * GDB now supports a faster verification that a .debug file matches its binary
3406 according to its build-id signature, if the signature is present.
3412 Enable or disable hardware flow control (RTS/CTS) on the serial port
3413 when debugging using remote targets.
3415 set mem inaccessible-by-default
3416 show mem inaccessible-by-default
3417 If the target supplies a memory map, for instance via the remote
3418 protocol's "qXfer:memory-map:read" packet, setting this variable
3419 prevents GDB from accessing memory outside the memory map. This
3420 is useful for targets with memory mapped registers or which react
3421 badly to accesses of unmapped address space.
3423 set breakpoint auto-hw
3424 show breakpoint auto-hw
3425 If the target supplies a memory map, for instance via the remote
3426 protocol's "qXfer:memory-map:read" packet, setting this variable
3427 lets GDB use hardware breakpoints automatically for memory regions
3428 where it can not use software breakpoints. This covers both the
3429 "break" command and internal breakpoints used for other commands
3430 including "next" and "finish".
3433 catch exception unhandled
3434 Stop the program execution when Ada exceptions are raised.
3437 Stop the program execution when an Ada assertion failed.
3441 Set an alternate system root for target files. This is a more
3442 general version of "set solib-absolute-prefix", which is now
3443 an alias to "set sysroot".
3446 Provide extended SPU facility status information. This set of
3447 commands is available only when debugging the Cell/B.E. SPU
3450 * New native configurations
3452 OpenBSD/sh sh*-*openbsd*
3455 unset tdesc filename
3457 Use the specified local file as an XML target description, and do
3458 not query the target for its built-in description.
3462 OpenBSD/sh sh*-*-openbsd*
3463 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3464 Toshiba Media Processor mep-elf
3466 * New remote packets
3469 Ignore the specified signals; pass them directly to the debugged program
3470 without stopping other threads or reporting them to GDB.
3472 qXfer:features:read:
3473 Read an XML target description from the target, which describes its
3478 Read or write contents of an spufs file on the target system. These
3479 packets are available only on the Cell/B.E. SPU architecture.
3481 qXfer:libraries:read:
3482 Report the loaded shared libraries. Combined with new "T" packet
3483 response, this packet allows GDB to debug shared libraries on
3484 targets where the operating system manages the list of loaded
3485 libraries (e.g. Windows and SymbianOS).
3489 Support for these obsolete configurations has been removed.
3497 i[34567]86-*-lynxos*
3498 i[34567]86-*-netware*
3499 i[34567]86-*-sco3.2v5*
3500 i[34567]86-*-sco3.2v4*
3502 i[34567]86-*-sysv4.2*
3505 i[34567]86-*-unixware2*
3506 i[34567]86-*-unixware*
3515 * Other removed features
3522 Various m68k-only ROM monitors.
3529 Various Renesas ROM monitors and debugging interfaces for SH and
3534 Support for a Macraigor serial interface to on-chip debugging.
3535 GDB does not directly support the newer parallel or USB
3540 A debug information format. The predecessor to DWARF 2 and
3541 DWARF 3, which are still supported.
3543 Support for the HP aCC compiler on HP-UX/PA-RISC
3545 SOM-encapsulated symbolic debugging information, automatic
3546 invocation of pxdb, and the aCC custom C++ ABI. This does not
3547 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3548 with aCC can still be debugged on an assembly level.
3550 MIPS ".pdr" sections
3552 A MIPS-specific format used to describe stack frame layout
3553 in debugging information.
3557 GDB could work with an older version of Guile to debug
3558 the interpreter and Scheme programs running in it.
3560 set mips stack-arg-size
3561 set mips saved-gpreg-size
3563 Use "set mips abi" to control parameter passing for MIPS.
3565 *** Changes in GDB 6.6
3570 Cell Broadband Engine SPU spu-elf
3572 * GDB can now be configured as a cross-debugger targeting native Windows
3573 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3574 running on a Windows system over TCP/IP to debug Windows programs.
3576 * The GDB remote stub, gdbserver, has been updated to support Windows and
3577 Cygwin debugging. Both single-threaded and multi-threaded programs are
3580 * The "set trust-readonly-sections" command works again. This command was
3581 broken in GDB 6.3, 6.4, and 6.5.
3583 * The "load" command now supports writing to flash memory, if the remote
3584 stub provides the required support.
3586 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3587 longer requires symbolic debug information (e.g. DWARF-2).
3592 unset substitute-path
3593 show substitute-path
3594 Manage a list of substitution rules that GDB uses to rewrite the name
3595 of the directories where the sources are located. This can be useful
3596 for instance when the sources were moved to a different location
3597 between compilation and debugging.
3601 Print each CLI command as it is executed. Each command is prefixed with
3602 a number of `+' symbols representing the nesting depth.
3603 The source command now has a `-v' option to enable the same feature.
3607 The ARM Demon monitor support (RDP protocol, "target rdp").
3609 Kernel Object Display, an embedded debugging feature which only worked with
3610 an obsolete version of Cisco IOS.
3612 The 'set download-write-size' and 'show download-write-size' commands.
3614 * New remote packets
3617 Tell a stub about GDB client features, and request remote target features.
3618 The first feature implemented is PacketSize, which allows the target to
3619 specify the size of packets it can handle - to minimize the number of
3620 packets required and improve performance when connected to a remote
3624 Fetch an OS auxilliary vector from the remote stub. This packet is a
3625 more efficient replacement for qPart:auxv:read.
3627 qXfer:memory-map:read:
3628 Fetch a memory map from the remote stub, including information about
3629 RAM, ROM, and flash memory devices.
3634 Erase and program a flash memory device.
3636 * Removed remote packets
3639 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3640 used it, and only gdbserver implemented it.
3642 *** Changes in GDB 6.5
3646 Renesas M32C/M16C m32c-elf
3648 Morpho Technologies ms1 ms1-elf
3652 init-if-undefined Initialize a convenience variable, but
3653 only if it doesn't already have a value.
3655 The following commands are presently only implemented for native GNU/Linux:
3657 checkpoint Save a snapshot of the program state.
3659 restart <n> Return the program state to a
3660 previously saved state.
3662 info checkpoints List currently saved checkpoints.
3664 delete-checkpoint <n> Delete a previously saved checkpoint.
3666 set|show detach-on-fork Tell gdb whether to detach from a newly
3667 forked process, or to keep debugging it.
3669 info forks List forks of the user program that
3670 are available to be debugged.
3672 fork <n> Switch to debugging one of several
3673 forks of the user program that are
3674 available to be debugged.
3676 delete-fork <n> Delete a fork from the list of forks
3677 that are available to be debugged (and
3678 kill the forked process).
3680 detach-fork <n> Delete a fork from the list of forks
3681 that are available to be debugged (and
3682 allow the process to continue).
3686 Morpho Technologies ms2 ms1-elf
3688 * Improved Windows host support
3690 GDB now builds as a cross debugger hosted on i686-mingw32, including
3691 native console support, and remote communications using either
3692 network sockets or serial ports.
3694 * Improved Modula-2 language support
3696 GDB can now print most types in the Modula-2 syntax. This includes:
3697 basic types, set types, record types, enumerated types, range types,
3698 pointer types and ARRAY types. Procedure var parameters are correctly
3699 printed and hexadecimal addresses and character constants are also
3700 written in the Modula-2 syntax. Best results can be obtained by using
3701 GNU Modula-2 together with the -gdwarf-2 command line option.
3705 The ARM rdi-share module.
3707 The Netware NLM debug server.
3709 *** Changes in GDB 6.4
3711 * New native configurations
3713 OpenBSD/arm arm*-*-openbsd*
3714 OpenBSD/mips64 mips64-*-openbsd*
3718 Morpho Technologies ms1 ms1-elf
3720 * New command line options
3722 --batch-silent As for --batch, but totally silent.
3723 --return-child-result The debugger will exist with the same value
3724 the child (debugged) program exited with.
3725 --eval-command COMMAND, -ex COMMAND
3726 Execute a single GDB CLI command. This may be
3727 specified multiple times and in conjunction
3728 with the --command (-x) option.
3730 * Deprecated commands removed
3732 The following commands, that were deprecated in 2000, have been
3736 set|show arm disassembly-flavor set|show arm disassembler
3737 othernames set arm disassembler
3738 set|show remotedebug set|show debug remote
3739 set|show archdebug set|show debug arch
3740 set|show eventdebug set|show debug event
3743 * New BSD user-level threads support
3745 It is now possible to debug programs using the user-level threads
3746 library on OpenBSD and FreeBSD. Currently supported (target)
3749 FreeBSD/amd64 x86_64-*-freebsd*
3750 FreeBSD/i386 i386-*-freebsd*
3751 OpenBSD/i386 i386-*-openbsd*
3753 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3754 are not yet supported.
3756 * New support for Matsushita MN10300 w/sim added
3757 (Work in progress). mn10300-elf.
3759 * REMOVED configurations and files
3761 VxWorks and the XDR protocol *-*-vxworks
3762 Motorola MCORE mcore-*-*
3763 National Semiconductor NS32000 ns32k-*-*
3765 * New "set print array-indexes" command
3767 After turning this setting "on", GDB prints the index of each element
3768 when displaying arrays. The default is "off" to preserve the previous
3771 * VAX floating point support
3773 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3775 * User-defined command support
3777 In addition to using $arg0..$arg9 for argument passing, it is now possible
3778 to use $argc to determine now many arguments have been passed. See the
3779 section on user-defined commands in the user manual for more information.
3781 *** Changes in GDB 6.3:
3783 * New command line option
3785 GDB now accepts -l followed by a number to set the timeout for remote
3788 * GDB works with GCC -feliminate-dwarf2-dups
3790 GDB now supports a more compact representation of DWARF-2 debug
3791 information using DW_FORM_ref_addr references. These are produced
3792 by GCC with the option -feliminate-dwarf2-dups and also by some
3793 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3794 to use -feliminate-dwarf2-dups.
3796 * Internationalization
3798 When supported by the host system, GDB will be built with
3799 internationalization (libintl). The task of marking up the sources is
3800 continued, we're looking forward to our first translation.
3804 Initial support for debugging programs compiled with the GNAT
3805 implementation of the Ada programming language has been integrated
3806 into GDB. In this release, support is limited to expression evaluation.
3808 * New native configurations
3810 GNU/Linux/m32r m32r-*-linux-gnu
3814 GDB's remote protocol now includes support for the 'p' packet. This
3815 packet is used to fetch individual registers from a remote inferior.
3817 * END-OF-LIFE registers[] compatibility module
3819 GDB's internal register infrastructure has been completely rewritten.
3820 The new infrastructure making possible the implementation of key new
3821 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3824 GDB 6.3 will be the last release to include the the registers[]
3825 compatibility module that allowed out-of-date configurations to
3826 continue to work. This change directly impacts the following
3836 powerpc bdm protocol
3838 Unless there is activity to revive these configurations, they will be
3839 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3841 * OBSOLETE configurations and files
3843 Configurations that have been declared obsolete in this release have
3844 been commented out. Unless there is activity to revive these
3845 configurations, the next release of GDB will have their sources
3846 permanently REMOVED.
3855 *** Changes in GDB 6.2.1:
3857 * MIPS `break main; run' gave an heuristic-fence-post warning
3859 When attempting to run even a simple program, a warning about
3860 heuristic-fence-post being hit would be reported. This problem has
3863 * MIPS IRIX 'long double' crashed GDB
3865 When examining a long double variable, GDB would get a segmentation
3866 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3867 IRIX long double values).
3871 A bug in the VAX stack code was causing problems with the "next"
3872 command. This problem has been fixed.
3874 *** Changes in GDB 6.2:
3876 * Fix for ``many threads''
3878 On GNU/Linux systems that use the NPTL threads library, a program
3879 rapidly creating and deleting threads would confuse GDB leading to the
3882 ptrace: No such process.
3883 thread_db_get_info: cannot get thread info: generic error
3885 This problem has been fixed.
3887 * "-async" and "-noasync" options removed.
3889 Support for the broken "-noasync" option has been removed (it caused
3892 * New ``start'' command.
3894 This command runs the program until the begining of the main procedure.
3896 * New BSD Kernel Data Access Library (libkvm) interface
3898 Using ``target kvm'' it is now possible to debug kernel core dumps and
3899 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3900 platforms. Currently supported (native-only) configurations are:
3902 FreeBSD/amd64 x86_64-*-freebsd*
3903 FreeBSD/i386 i?86-*-freebsd*
3904 NetBSD/i386 i?86-*-netbsd*
3905 NetBSD/m68k m68*-*-netbsd*
3906 NetBSD/sparc sparc-*-netbsd*
3907 OpenBSD/amd64 x86_64-*-openbsd*
3908 OpenBSD/i386 i?86-*-openbsd*
3909 OpenBSD/m68k m68*-openbsd*
3910 OpenBSD/sparc sparc-*-openbsd*
3912 * Signal trampoline code overhauled
3914 Many generic problems with GDB's signal handling code have been fixed.
3915 These include: backtraces through non-contiguous stacks; recognition
3916 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3917 call; backtrace through a signal trampoline; step into and out of
3918 signal handlers; and single-stepping in the signal trampoline.
3920 Please note that kernel bugs are a limiting factor here. These
3921 features have been shown to work on an s390 GNU/Linux system that
3922 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3924 * Cygwin support for DWARF 2 added.
3926 * New native configurations
3928 GNU/Linux/hppa hppa*-*-linux*
3929 OpenBSD/hppa hppa*-*-openbsd*
3930 OpenBSD/m68k m68*-*-openbsd*
3931 OpenBSD/m88k m88*-*-openbsd*
3932 OpenBSD/powerpc powerpc-*-openbsd*
3933 NetBSD/vax vax-*-netbsd*
3934 OpenBSD/vax vax-*-openbsd*
3936 * END-OF-LIFE frame compatibility module
3938 GDB's internal frame infrastructure has been completely rewritten.
3939 The new infrastructure making it possible to support key new features
3940 including DWARF 2 Call Frame Information. To aid in the task of
3941 migrating old configurations to this new infrastructure, a
3942 compatibility module, that allowed old configurations to continue to
3943 work, was also included.
3945 GDB 6.2 will be the last release to include this frame compatibility
3946 module. This change directly impacts the following configurations:
3956 Unless there is activity to revive these configurations, they will be
3957 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3959 * REMOVED configurations and files
3961 Sun 3, running SunOS 3 m68*-*-sunos3*
3962 Sun 3, running SunOS 4 m68*-*-sunos4*
3963 Sun 2, running SunOS 3 m68000-*-sunos3*
3964 Sun 2, running SunOS 4 m68000-*-sunos4*
3965 Motorola 680x0 running LynxOS m68*-*-lynxos*
3966 AT&T 3b1/Unix pc m68*-att-*
3967 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3968 decstation mips-dec-* mips-little-*
3969 riscos mips-*-riscos* mips-*-sysv*
3970 sonymips mips-sony-*
3971 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3973 *** Changes in GDB 6.1.1:
3975 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3977 The TUI (Text-mode User Interface) is now built as part of a default
3978 GDB configuration. It is enabled by either selecting the TUI with the
3979 command line option "-i=tui" or by running the separate "gdbtui"
3980 program. For more information on the TUI, see the manual "Debugging
3983 * Pending breakpoint support (also included in GDB 6.1)
3985 Support has been added to allow you to specify breakpoints in shared
3986 libraries that have not yet been loaded. If a breakpoint location
3987 cannot be found, and the "breakpoint pending" option is set to auto,
3988 GDB queries you if you wish to make the breakpoint pending on a future
3989 shared-library load. If and when GDB resolves the breakpoint symbol,
3990 the pending breakpoint is removed as one or more regular breakpoints
3993 Pending breakpoints are very useful for GCJ Java debugging.
3995 * Fixed ISO-C build problems
3997 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3998 non ISO-C code that stopped them being built using a more strict ISO-C
3999 compiler (e.g., IBM's C compiler).
4001 * Fixed build problem on IRIX 5
4003 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4004 wasn't able to compile compile on an IRIX 5 system.
4006 * Added execute permission to gdb/gdbserver/configure
4008 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4009 permission. This bug would cause configure to fail on a number of
4010 systems (Solaris, IRIX). Ref: server/519.
4012 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4014 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4015 has been updated to use constant array sizes.
4017 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4019 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4020 its generated DWARF Call Frame Info. This encoding was causing GDB to
4021 panic, that panic has been fixed. Ref: gdb/1628.
4023 * Fixed a problem when examining parameters in shared library code.
4025 When examining parameters in optimized shared library code generated
4026 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4027 not available''. GDB now correctly displays the variable's value.
4029 *** Changes in GDB 6.1:
4031 * Removed --with-mmalloc
4033 Support for the mmalloc memory manager has been removed, as it
4034 conflicted with the internal gdb byte cache.
4036 * Changes in AMD64 configurations
4038 The AMD64 target now includes the %cs and %ss registers. As a result
4039 the AMD64 remote protocol has changed; this affects the floating-point
4040 and SSE registers. If you rely on those registers for your debugging,
4041 you should upgrade gdbserver on the remote side.
4043 * Revised SPARC target
4045 The SPARC target has been completely revised, incorporating the
4046 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4047 support for LynxOS and SunOS 4 has been dropped. Calling functions
4048 from within GDB on operating systems with a non-executable stack
4049 (Solaris, OpenBSD) now works.
4053 GDB has a new C++ demangler which does a better job on the mangled
4054 names generated by current versions of g++. It also runs faster, so
4055 with this and other changes gdb should now start faster on large C++
4058 * DWARF 2 Location Expressions
4060 GDB support for location expressions has been extended to support function
4061 arguments and frame bases. Older versions of GDB could crash when they
4064 * C++ nested types and namespaces
4066 GDB's support for nested types and namespaces in C++ has been
4067 improved, especially if you use the DWARF 2 debugging format. (This
4068 is the default for recent versions of GCC on most platforms.)
4069 Specifically, if you have a class "Inner" defined within a class or
4070 namespace "Outer", then GDB realizes that the class's name is
4071 "Outer::Inner", not simply "Inner". This should greatly reduce the
4072 frequency of complaints about not finding RTTI symbols. In addition,
4073 if you are stopped at inside of a function defined within a namespace,
4074 GDB modifies its name lookup accordingly.
4076 * New native configurations
4078 NetBSD/amd64 x86_64-*-netbsd*
4079 OpenBSD/amd64 x86_64-*-openbsd*
4080 OpenBSD/alpha alpha*-*-openbsd*
4081 OpenBSD/sparc sparc-*-openbsd*
4082 OpenBSD/sparc64 sparc64-*-openbsd*
4084 * New debugging protocols
4086 M32R with SDI protocol m32r-*-elf*
4088 * "set prompt-escape-char" command deleted.
4090 The command "set prompt-escape-char" has been deleted. This command,
4091 and its very obscure effet on GDB's prompt, was never documented,
4092 tested, nor mentioned in the NEWS file.
4094 * OBSOLETE configurations and files
4096 Configurations that have been declared obsolete in this release have
4097 been commented out. Unless there is activity to revive these
4098 configurations, the next release of GDB will have their sources
4099 permanently REMOVED.
4101 Sun 3, running SunOS 3 m68*-*-sunos3*
4102 Sun 3, running SunOS 4 m68*-*-sunos4*
4103 Sun 2, running SunOS 3 m68000-*-sunos3*
4104 Sun 2, running SunOS 4 m68000-*-sunos4*
4105 Motorola 680x0 running LynxOS m68*-*-lynxos*
4106 AT&T 3b1/Unix pc m68*-att-*
4107 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4108 decstation mips-dec-* mips-little-*
4109 riscos mips-*-riscos* mips-*-sysv*
4110 sonymips mips-sony-*
4111 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4113 * REMOVED configurations and files
4115 SGI Irix-4.x mips-sgi-irix4 or iris4
4116 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4117 Z8000 simulator z8k-zilog-none or z8ksim
4118 Matsushita MN10200 w/simulator mn10200-*-*
4119 H8/500 simulator h8500-hitachi-hms or h8500hms
4120 HP/PA running BSD hppa*-*-bsd*
4121 HP/PA running OSF/1 hppa*-*-osf*
4122 HP/PA Pro target hppa*-*-pro*
4123 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4124 386BSD i[3456]86-*-bsd*
4125 Sequent family i[3456]86-sequent-sysv4*
4126 i[3456]86-sequent-sysv*
4127 i[3456]86-sequent-bsd*
4128 SPARC running LynxOS sparc-*-lynxos*
4129 SPARC running SunOS 4 sparc-*-sunos4*
4130 Tsqware Sparclet sparclet-*-*
4131 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4133 *** Changes in GDB 6.0:
4137 Support for debugging the Objective-C programming language has been
4138 integrated into GDB.
4140 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4142 DWARF 2's Call Frame Information makes available compiler generated
4143 information that more exactly describes the program's run-time stack.
4144 By using this information, GDB is able to provide more robust stack
4147 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4148 have been updated to use a new backtrace mechanism which includes
4149 DWARF 2 CFI support.
4153 GDB's remote protocol has been extended to include support for hosted
4154 file I/O (where the remote target uses GDB's file system). See GDB's
4155 remote protocol documentation for details.
4157 * All targets using the new architecture framework.
4159 All of GDB's targets have been updated to use the new internal
4160 architecture framework. The way is now open for future GDB releases
4161 to include cross-architecture native debugging support (i386 on amd64,
4164 * GNU/Linux's Thread Local Storage (TLS)
4166 GDB now includes support for for the GNU/Linux implementation of
4167 per-thread variables.
4169 * GNU/Linux's Native POSIX Thread Library (NPTL)
4171 GDB's thread code has been updated to work with either the new
4172 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4174 * Separate debug info.
4176 GDB, in conjunction with BINUTILS, now supports a mechanism for
4177 automatically loading debug information from a separate file. Instead
4178 of shipping full debug and non-debug versions of system libraries,
4179 system integrators can now instead ship just the stripped libraries
4180 and optional debug files.
4182 * DWARF 2 Location Expressions
4184 DWARF 2 Location Expressions allow the compiler to more completely
4185 describe the location of variables (even in optimized code) to the
4188 GDB now includes preliminary support for location expressions (support
4189 for DW_OP_piece is still missing).
4193 A number of long standing bugs that caused GDB to die while starting a
4194 Java application have been fixed. GDB's Java support is now
4195 considered "useable".
4197 * GNU/Linux support for fork, vfork, and exec.
4199 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4200 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4203 * GDB supports logging output to a file
4205 There are two new commands, "set logging" and "show logging", which can be
4206 used to capture GDB's output to a file.
4208 * The meaning of "detach" has changed for gdbserver
4210 The "detach" command will now resume the application, as documented. To
4211 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4214 * d10v, m68hc11 `regs' command deprecated
4216 The `info registers' command has been updated so that it displays the
4217 registers using a format identical to the old `regs' command.
4221 A new command, "maint set profile on/off", has been added. This command can
4222 be used to enable or disable profiling while running GDB, to profile a
4223 session or a set of commands. In addition there is a new configure switch,
4224 "--enable-profiling", which will cause GDB to be compiled with profiling
4225 data, for more informative profiling results.
4227 * Default MI syntax changed to "mi2".
4229 The default MI (machine interface) syntax, enabled by the command line
4230 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4231 "mi1", can be enabled by specifying the option "-i=mi1".
4233 Support for the original "mi0" syntax (included in GDB 5.0) has been
4236 Fix for gdb/192: removed extraneous space when displaying frame level.
4237 Fix for gdb/672: update changelist is now output in mi list format.
4238 Fix for gdb/702: a -var-assign that updates the value now shows up
4239 in a subsequent -var-update.
4241 * New native configurations.
4243 FreeBSD/amd64 x86_64-*-freebsd*
4245 * Multi-arched targets.
4247 HP/PA HPUX11 hppa*-*-hpux*
4248 Renesas M32R/D w/simulator m32r-*-elf*
4250 * OBSOLETE configurations and files
4252 Configurations that have been declared obsolete in this release have
4253 been commented out. Unless there is activity to revive these
4254 configurations, the next release of GDB will have their sources
4255 permanently REMOVED.
4257 Z8000 simulator z8k-zilog-none or z8ksim
4258 Matsushita MN10200 w/simulator mn10200-*-*
4259 H8/500 simulator h8500-hitachi-hms or h8500hms
4260 HP/PA running BSD hppa*-*-bsd*
4261 HP/PA running OSF/1 hppa*-*-osf*
4262 HP/PA Pro target hppa*-*-pro*
4263 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4264 Sequent family i[3456]86-sequent-sysv4*
4265 i[3456]86-sequent-sysv*
4266 i[3456]86-sequent-bsd*
4267 Tsqware Sparclet sparclet-*-*
4268 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4270 * REMOVED configurations and files
4273 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4274 IBM AIX PS/2 i[3456]86-*-aix
4275 i386 running Mach 3.0 i[3456]86-*-mach3*
4276 i386 running Mach i[3456]86-*-mach*
4277 i386 running OSF/1 i[3456]86-*osf1mk*
4278 HP/Apollo 68k Family m68*-apollo*-sysv*,
4280 m68*-hp-bsd*, m68*-hp-hpux*
4281 Argonaut Risc Chip (ARC) arc-*-*
4282 Mitsubishi D30V d30v-*-*
4283 Fujitsu FR30 fr30-*-elf*
4284 OS/9000 i[34]86-*-os9k
4285 I960 with MON960 i960-*-coff
4287 * MIPS $fp behavior changed
4289 The convenience variable $fp, for the MIPS, now consistently returns
4290 the address of the current frame's base. Previously, depending on the
4291 context, $fp could refer to either $sp or the current frame's base
4292 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4293 The GNU Source-Level Debugger''.
4295 *** Changes in GDB 5.3:
4297 * GNU/Linux shared library multi-threaded performance improved.
4299 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4300 `/proc', in preference to `ptrace' for memory reads. This may result
4301 in an improvement in the start-up time of multi-threaded, shared
4302 library applications when run under GDB. One GDB user writes: ``loads
4303 shared libs like mad''.
4305 * ``gdbserver'' now supports multi-threaded applications on some targets
4307 Support for debugging multi-threaded applications which use
4308 the GNU/Linux LinuxThreads package has been added for
4309 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4310 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4312 * GDB now supports C/C++ preprocessor macros.
4314 GDB now expands preprocessor macro invocations in C/C++ expressions,
4315 and provides various commands for showing macro definitions and how
4318 The new command `macro expand EXPRESSION' expands any macro
4319 invocations in expression, and shows the result.
4321 The new command `show macro MACRO-NAME' shows the definition of the
4322 macro named MACRO-NAME, and where it was defined.
4324 Most compilers don't include information about macros in the debugging
4325 information by default. In GCC 3.1, for example, you need to compile
4326 your program with the options `-gdwarf-2 -g3'. If the macro
4327 information is present in the executable, GDB will read it.
4329 * Multi-arched targets.
4331 DEC Alpha (partial) alpha*-*-*
4332 DEC VAX (partial) vax-*-*
4334 National Semiconductor NS32000 (partial) ns32k-*-*
4335 Motorola 68000 (partial) m68k-*-*
4336 Motorola MCORE mcore-*-*
4340 Fujitsu FRV architecture added by Red Hat frv*-*-*
4343 * New native configurations
4345 Alpha NetBSD alpha*-*-netbsd*
4346 SH NetBSD sh*-*-netbsdelf*
4347 MIPS NetBSD mips*-*-netbsd*
4348 UltraSPARC NetBSD sparc64-*-netbsd*
4350 * OBSOLETE configurations and files
4352 Configurations that have been declared obsolete in this release have
4353 been commented out. Unless there is activity to revive these
4354 configurations, the next release of GDB will have their sources
4355 permanently REMOVED.
4357 Mitsubishi D30V d30v-*-*
4358 OS/9000 i[34]86-*-os9k
4359 IBM AIX PS/2 i[3456]86-*-aix
4360 Fujitsu FR30 fr30-*-elf*
4361 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4362 Argonaut Risc Chip (ARC) arc-*-*
4363 i386 running Mach 3.0 i[3456]86-*-mach3*
4364 i386 running Mach i[3456]86-*-mach*
4365 i386 running OSF/1 i[3456]86-*osf1mk*
4366 HP/Apollo 68k Family m68*-apollo*-sysv*,
4368 m68*-hp-bsd*, m68*-hp-hpux*
4369 I960 with MON960 i960-*-coff
4371 * OBSOLETE languages
4373 CHILL, a Pascal like language used by telecommunications companies.
4375 * REMOVED configurations and files
4377 AMD 29k family via UDI a29k-amd-udi, udi29k
4378 A29K VxWorks a29k-*-vxworks
4379 AMD 29000 embedded, using EBMON a29k-none-none
4380 AMD 29000 embedded with COFF a29k-none-coff
4381 AMD 29000 embedded with a.out a29k-none-aout
4383 testsuite/gdb.hp/gdb.threads-hp/ directory
4385 * New command "set max-user-call-depth <nnn>"
4387 This command allows the user to limit the call depth of user-defined
4388 commands. The default is 1024.
4390 * Changes in FreeBSD/i386 native debugging.
4392 Support for the "generate-core-file" has been added.
4394 * New commands "dump", "append", and "restore".
4396 These commands allow data to be copied from target memory
4397 to a bfd-format or binary file (dump and append), and back
4398 from a file into memory (restore).
4400 * Improved "next/step" support on multi-processor Alpha Tru64.
4402 The previous single-step mechanism could cause unpredictable problems,
4403 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4404 of a software single-step mechanism prevents this.
4406 *** Changes in GDB 5.2.1:
4414 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4415 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4416 Fix, by Joel Brobecker imported from mainline.
4418 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4419 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4420 Fix, by Fred Fish, imported from mainline.
4422 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4423 Surprisingly enough, it works now.
4424 By Michal Ludvig, imported from mainline.
4426 i386 hardware watchpoint support:
4427 avoid misses on second run for some targets.
4428 By Pierre Muller, imported from mainline.
4430 *** Changes in GDB 5.2:
4432 * New command "set trust-readonly-sections on[off]".
4434 This command is a hint that tells gdb that read-only sections
4435 really are read-only (ie. that their contents will not change).
4436 In this mode, gdb will go to the object file rather than the
4437 target to read memory from read-only sections (such as ".text").
4438 This can be a significant performance improvement on some
4439 (notably embedded) targets.
4441 * New command "generate-core-file" (or "gcore").
4443 This new gdb command allows the user to drop a core file of the child
4444 process state at any time. So far it's been implemented only for
4445 GNU/Linux and Solaris, but should be relatively easily ported to other
4446 hosts. Argument is core file name (defaults to core.<pid>).
4448 * New command line option
4450 GDB now accepts --pid or -p followed by a process id.
4452 * Change in command line behavior -- corefiles vs. process ids.
4454 There is a subtle behavior in the way in which GDB handles
4455 command line arguments. The first non-flag argument is always
4456 a program to debug, but the second non-flag argument may either
4457 be a corefile or a process id. Previously, GDB would attempt to
4458 open the second argument as a corefile, and if that failed, would
4459 issue a superfluous error message and then attempt to attach it as
4460 a process. Now, if the second argument begins with a non-digit,
4461 it will be treated as a corefile. If it begins with a digit,
4462 GDB will attempt to attach it as a process, and if no such process
4463 is found, will then attempt to open it as a corefile.
4465 * Changes in ARM configurations.
4467 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4468 configuration is fully multi-arch.
4470 * New native configurations
4472 ARM NetBSD arm*-*-netbsd*
4473 x86 OpenBSD i[3456]86-*-openbsd*
4474 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4475 Sparc64 running FreeBSD sparc64-*-freebsd*
4479 Sanyo XStormy16 xstormy16-elf
4481 * OBSOLETE configurations and files
4483 Configurations that have been declared obsolete in this release have
4484 been commented out. Unless there is activity to revive these
4485 configurations, the next release of GDB will have their sources
4486 permanently REMOVED.
4488 AMD 29k family via UDI a29k-amd-udi, udi29k
4489 A29K VxWorks a29k-*-vxworks
4490 AMD 29000 embedded, using EBMON a29k-none-none
4491 AMD 29000 embedded with COFF a29k-none-coff
4492 AMD 29000 embedded with a.out a29k-none-aout
4494 testsuite/gdb.hp/gdb.threads-hp/ directory
4496 * REMOVED configurations and files
4498 TI TMS320C80 tic80-*-*
4500 PowerPC Solaris powerpcle-*-solaris*
4501 PowerPC Windows NT powerpcle-*-cygwin32
4502 PowerPC Netware powerpc-*-netware*
4503 Harris/CXUX m88k m88*-harris-cxux*
4504 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4505 ns32k-utek-sysv* ns32k-utek-*
4506 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4507 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4508 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4509 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4510 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4512 * Changes to command line processing
4514 The new `--args' feature can be used to specify command-line arguments
4515 for the inferior from gdb's command line.
4517 * Changes to key bindings
4519 There is a new `operate-and-get-next' function bound to `C-o'.
4521 *** Changes in GDB 5.1.1
4523 Fix compile problem on DJGPP.
4525 Fix a problem with floating-point registers on the i386 being
4528 Fix to stop GDB crashing on .debug_str debug info.
4530 Numerous documentation fixes.
4532 Numerous testsuite fixes.
4534 *** Changes in GDB 5.1:
4536 * New native configurations
4538 Alpha FreeBSD alpha*-*-freebsd*
4539 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4540 MIPS GNU/Linux mips*-*-linux*
4541 MIPS SGI Irix 6.x mips*-sgi-irix6*
4542 ia64 AIX ia64-*-aix*
4543 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4547 Motorola 68HC11 and 68HC12 m68hc11-elf
4549 UltraSparc running GNU/Linux sparc64-*-linux*
4551 * OBSOLETE configurations and files
4553 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4554 Harris/CXUX m88k m88*-harris-cxux*
4555 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4556 ns32k-utek-sysv* ns32k-utek-*
4557 TI TMS320C80 tic80-*-*
4559 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4560 PowerPC Solaris powerpcle-*-solaris*
4561 PowerPC Windows NT powerpcle-*-cygwin32
4562 PowerPC Netware powerpc-*-netware*
4563 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4564 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4565 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4566 Apple Macintosh (MPW) host N/A
4568 stuff.c (Program to stuff files into a specially prepared space in kdb)
4569 kdb-start.c (Main loop for the standalone kernel debugger)
4571 Configurations that have been declared obsolete in this release have
4572 been commented out. Unless there is activity to revive these
4573 configurations, the next release of GDB will have their sources
4574 permanently REMOVED.
4576 * REMOVED configurations and files
4578 Altos 3068 m68*-altos-*
4579 Convex c1-*-*, c2-*-*
4581 ARM RISCix arm-*-* (as host)
4585 * GDB has been converted to ISO C.
4587 GDB's source code has been converted to ISO C. In particular, the
4588 sources are fully protoized, and rely on standard headers being
4593 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4595 * The MI enabled by default.
4597 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4598 revised and enabled by default. Packages which use GDB as a debugging
4599 engine behind a UI or another front end are encouraged to switch to
4600 using the GDB/MI interface, instead of the old annotations interface
4601 which is now deprecated.
4603 * Support for debugging Pascal programs.
4605 GDB now includes support for debugging Pascal programs. The following
4606 main features are supported:
4608 - Pascal-specific data types such as sets;
4610 - automatic recognition of Pascal sources based on file-name
4613 - Pascal-style display of data types, variables, and functions;
4615 - a Pascal expression parser.
4617 However, some important features are not yet supported.
4619 - Pascal string operations are not supported at all;
4621 - there are some problems with boolean types;
4623 - Pascal type hexadecimal constants are not supported
4624 because they conflict with the internal variables format;
4626 - support for Pascal objects and classes is not full yet;
4628 - unlike Pascal, GDB is case-sensitive for symbol names.
4630 * Changes in completion.
4632 Commands such as `shell', `run' and `set args', which pass arguments
4633 to inferior programs, now complete on file names, similar to what
4634 users expect at the shell prompt.
4636 Commands which accept locations, such as `disassemble', `print',
4637 `breakpoint', `until', etc. now complete on filenames as well as
4638 program symbols. Thus, if you type "break foob TAB", and the source
4639 files linked into the programs include `foobar.c', that file name will
4640 be one of the candidates for completion. However, file names are not
4641 considered for completion after you typed a colon that delimits a file
4642 name from a name of a function in that file, as in "break foo.c:bar".
4644 `set demangle-style' completes on available demangling styles.
4646 * New platform-independent commands:
4648 It is now possible to define a post-hook for a command as well as a
4649 hook that runs before the command. For more details, see the
4650 documentation of `hookpost' in the GDB manual.
4652 * Changes in GNU/Linux native debugging.
4654 Support for debugging multi-threaded programs has been completely
4655 revised for all platforms except m68k and sparc. You can now debug as
4656 many threads as your system allows you to have.
4658 Attach/detach is supported for multi-threaded programs.
4660 Support for SSE registers was added for x86. This doesn't work for
4661 multi-threaded programs though.
4663 * Changes in MIPS configurations.
4665 Multi-arch support is enabled for all MIPS configurations.
4667 GDB can now be built as native debugger on SGI Irix 6.x systems for
4668 debugging n32 executables. (Debugging 64-bit executables is not yet
4671 * Unified support for hardware watchpoints in all x86 configurations.
4673 Most (if not all) native x86 configurations support hardware-assisted
4674 breakpoints and watchpoints in a unified manner. This support
4675 implements debug register sharing between watchpoints, which allows to
4676 put a virtually infinite number of watchpoints on the same address,
4677 and also supports watching regions up to 16 bytes with several debug
4680 The new maintenance command `maintenance show-debug-regs' toggles
4681 debugging print-outs in functions that insert, remove, and test
4682 watchpoints and hardware breakpoints.
4684 * Changes in the DJGPP native configuration.
4686 New command ``info dos sysinfo'' displays assorted information about
4687 the CPU, OS, memory, and DPMI server.
4689 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4690 display information about segment descriptors stored in GDT, LDT, and
4693 New commands ``info dos pde'' and ``info dos pte'' display entries
4694 from Page Directory and Page Tables (for now works with CWSDPMI only).
4695 New command ``info dos address-pte'' displays the Page Table entry for
4696 a given linear address.
4698 GDB can now pass command lines longer than 126 characters to the
4699 program being debugged (requires an update to the libdbg.a library
4700 which is part of the DJGPP development kit).
4702 DWARF2 debug info is now supported.
4704 It is now possible to `step' and `next' through calls to `longjmp'.
4706 * Changes in documentation.
4708 All GDB documentation was converted to GFDL, the GNU Free
4709 Documentation License.
4711 Tracepoints-related commands are now fully documented in the GDB
4714 TUI, the Text-mode User Interface, is now documented in the manual.
4716 Tracepoints-related commands are now fully documented in the GDB
4719 The "GDB Internals" manual now has an index. It also includes
4720 documentation of `ui_out' functions, GDB coding standards, x86
4721 hardware watchpoints, and memory region attributes.
4723 * GDB's version number moved to ``version.in''
4725 The Makefile variable VERSION has been replaced by the file
4726 ``version.in''. People creating GDB distributions should update the
4727 contents of this file.
4731 GUD support is now a standard part of the EMACS distribution.
4733 *** Changes in GDB 5.0:
4735 * Improved support for debugging FP programs on x86 targets
4737 Unified and much-improved support for debugging floating-point
4738 programs on all x86 targets. In particular, ``info float'' now
4739 displays the FP registers in the same format on all x86 targets, with
4740 greater level of detail.
4742 * Improvements and bugfixes in hardware-assisted watchpoints
4744 It is now possible to watch array elements, struct members, and
4745 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4746 on x86 targets no longer erroneously trigger when the address is
4749 * Improvements in the native DJGPP version of GDB
4751 The distribution now includes all the scripts and auxiliary files
4752 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4753 machines ``out of the box''.
4755 The DJGPP version can now debug programs that use signals. It is
4756 possible to catch signals that happened in the debuggee, deliver
4757 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4758 would kill the program being debugged.) Programs that hook hardware
4759 interrupts (keyboard, timer, etc.) can also be debugged.
4761 It is now possible to debug DJGPP programs that redirect their
4762 standard handles or switch them to raw (as opposed to cooked) mode, or
4763 even close them. The command ``run < foo > bar'' works as expected,
4764 and ``info terminal'' reports useful information about the debuggee's
4765 terminal, including raw/cooked mode, redirection, etc.
4767 The DJGPP version now uses termios functions for console I/O, which
4768 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4771 DOS-style file names with drive letters are now fully supported by
4774 It is now possible to debug DJGPP programs that switch their working
4775 directory. It is also possible to rerun the debuggee any number of
4776 times without restarting GDB; thus, you can use the same setup,
4777 breakpoints, etc. for many debugging sessions.
4779 * New native configurations
4781 ARM GNU/Linux arm*-*-linux*
4782 PowerPC GNU/Linux powerpc-*-linux*
4786 Motorola MCore mcore-*-*
4787 x86 VxWorks i[3456]86-*-vxworks*
4788 PowerPC VxWorks powerpc-*-vxworks*
4789 TI TMS320C80 tic80-*-*
4791 * OBSOLETE configurations
4793 Altos 3068 m68*-altos-*
4794 Convex c1-*-*, c2-*-*
4796 ARM RISCix arm-*-* (as host)
4799 Configurations that have been declared obsolete will be commented out,
4800 but the code will be left in place. If there is no activity to revive
4801 these configurations before the next release of GDB, the sources will
4802 be permanently REMOVED.
4804 * Gould support removed
4806 Support for the Gould PowerNode and NP1 has been removed.
4808 * New features for SVR4
4810 On SVR4 native platforms (such as Solaris), if you attach to a process
4811 without first loading a symbol file, GDB will now attempt to locate and
4812 load symbols from the running process's executable file.
4814 * Many C++ enhancements
4816 C++ support has been greatly improved. Overload resolution now works properly
4817 in almost all cases. RTTI support is on the way.
4819 * Remote targets can connect to a sub-program
4821 A popen(3) style serial-device has been added. This device starts a
4822 sub-process (such as a stand-alone simulator) and then communicates
4823 with that. The sub-program to run is specified using the syntax
4824 ``|<program> <args>'' vis:
4826 (gdb) set remotedebug 1
4827 (gdb) target extended-remote |mn10300-elf-sim program-args
4829 * MIPS 64 remote protocol
4831 A long standing bug in the mips64 remote protocol where by GDB
4832 expected certain 32 bit registers (ex SR) to be transfered as 32
4833 instead of 64 bits has been fixed.
4835 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4836 added to provide backward compatibility with older versions of GDB.
4838 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4840 The command ``set remotebinarydownload'' command has been replaced by
4841 ``set remote X-packet''. Other commands in ``set remote'' family
4842 include ``set remote P-packet''.
4844 * Breakpoint commands accept ranges.
4846 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4847 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4848 ``tracepoint passcount'' also accepts a range of tracepoints.
4850 * ``apropos'' command added.
4852 The ``apropos'' command searches through command names and
4853 documentation strings, printing out matches, making it much easier to
4854 try to find a command that does what you are looking for.
4858 A new machine oriented interface (MI) has been added to GDB. This
4859 interface is designed for debug environments running GDB as a separate
4860 process. This is part of the long term libGDB project. See the
4861 "GDB/MI" chapter of the GDB manual for further information. It can be
4862 enabled by configuring with:
4864 .../configure --enable-gdbmi
4866 *** Changes in GDB-4.18:
4868 * New native configurations
4870 HP-UX 10.20 hppa*-*-hpux10.20
4871 HP-UX 11.x hppa*-*-hpux11.0*
4872 M68K GNU/Linux m68*-*-linux*
4876 Fujitsu FR30 fr30-*-elf*
4877 Intel StrongARM strongarm-*-*
4878 Mitsubishi D30V d30v-*-*
4880 * OBSOLETE configurations
4882 Gould PowerNode, NP1 np1-*-*, pn-*-*
4884 Configurations that have been declared obsolete will be commented out,
4885 but the code will be left in place. If there is no activity to revive
4886 these configurations before the next release of GDB, the sources will
4887 be permanently REMOVED.
4891 As a compatibility experiment, GDB's source files buildsym.h and
4892 buildsym.c have been converted to pure standard C, no longer
4893 containing any K&R compatibility code. We believe that all systems in
4894 use today either come with a standard C compiler, or have a GCC port
4895 available. If this is not true, please report the affected
4896 configuration to bug-gdb@gnu.org immediately. See the README file for
4897 information about getting a standard C compiler if you don't have one
4902 GDB now uses readline 2.2.
4904 * set extension-language
4906 You can now control the mapping between filename extensions and source
4907 languages by using the `set extension-language' command. For instance,
4908 you can ask GDB to treat .c files as C++ by saying
4909 set extension-language .c c++
4910 The command `info extensions' lists all of the recognized extensions
4911 and their associated languages.
4913 * Setting processor type for PowerPC and RS/6000
4915 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4916 you can use the `set processor' command to specify what variant of the
4917 PowerPC family you are debugging. The command
4921 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4922 following PowerPC and RS6000 variants:
4924 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4925 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4927 403GC IBM PowerPC 403GC
4928 505 Motorola PowerPC 505
4929 860 Motorola PowerPC 860 or 850
4930 601 Motorola PowerPC 601
4931 602 Motorola PowerPC 602
4932 603 Motorola/IBM PowerPC 603 or 603e
4933 604 Motorola PowerPC 604 or 604e
4934 750 Motorola/IBM PowerPC 750 or 750
4936 At the moment, this command just tells GDB what to name the
4937 special-purpose processor registers. Since almost all the affected
4938 registers are inaccessible to user-level programs, this command is
4939 only useful for remote debugging in its present form.
4943 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4944 more extensive support for HP-UX. Added features include shared
4945 library support, kernel threads and hardware watchpoints for 11.00,
4946 support for HP's ANSI C and C++ compilers, and a compatibility mode
4947 for xdb and dbx commands.
4951 HP's donation includes the new concept of catchpoints, which is a
4952 generalization of the old catch command. On HP-UX, it is now possible
4953 to catch exec, fork, and vfork, as well as library loading.
4955 This means that the existing catch command has changed; its first
4956 argument now specifies the type of catch to be set up. See the
4957 output of "help catch" for a list of catchpoint types.
4959 * Debugging across forks
4961 On HP-UX, you can choose which process to debug when a fork() happens
4966 HP has donated a curses-based terminal user interface (TUI). To get
4967 it, build with --enable-tui. Although this can be enabled for any
4968 configuration, at present it only works for native HP debugging.
4970 * GDB remote protocol additions
4972 A new protocol packet 'X' that writes binary data is now available.
4973 Default behavior is to try 'X', then drop back to 'M' if the stub
4974 fails to respond. The settable variable `remotebinarydownload'
4975 allows explicit control over the use of 'X'.
4977 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4978 full 64-bit address. The command
4980 set remoteaddresssize 32
4982 can be used to revert to the old behaviour. For existing remote stubs
4983 the change should not be noticed, as the additional address information
4986 In order to assist in debugging stubs, you may use the maintenance
4987 command `packet' to send any text string to the stub. For instance,
4989 maint packet heythere
4991 sends the packet "$heythere#<checksum>". Note that it is very easy to
4992 disrupt a debugging session by sending the wrong packet at the wrong
4995 The compare-sections command allows you to compare section data on the
4996 target to what is in the executable file without uploading or
4997 downloading, by comparing CRC checksums.
4999 * Tracing can collect general expressions
5001 You may now collect general expressions at tracepoints. This requires
5002 further additions to the target-side stub; see tracepoint.c and
5003 doc/agentexpr.texi for further details.
5005 * mask-address variable for Mips
5007 For Mips targets, you may control the zeroing of the upper 32 bits of
5008 a 64-bit address by entering `set mask-address on'. This is mainly
5009 of interest to users of embedded R4xxx and R5xxx processors.
5011 * Higher serial baud rates
5013 GDB's serial code now allows you to specify baud rates 57600, 115200,
5014 230400, and 460800 baud. (Note that your host system may not be able
5015 to achieve all of these rates.)
5019 The i960 configuration now includes an initial implementation of a
5020 builtin simulator, contributed by Jim Wilson.
5023 *** Changes in GDB-4.17:
5025 * New native configurations
5027 Alpha GNU/Linux alpha*-*-linux*
5028 Unixware 2.x i[3456]86-unixware2*
5029 Irix 6.x mips*-sgi-irix6*
5030 PowerPC GNU/Linux powerpc-*-linux*
5031 PowerPC Solaris powerpcle-*-solaris*
5032 Sparc GNU/Linux sparc-*-linux*
5033 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5037 Argonaut Risc Chip (ARC) arc-*-*
5038 Hitachi H8/300S h8300*-*-*
5039 Matsushita MN10200 w/simulator mn10200-*-*
5040 Matsushita MN10300 w/simulator mn10300-*-*
5041 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5042 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5043 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5044 Mitsubishi D10V w/simulator d10v-*-*
5045 Mitsubishi M32R/D w/simulator m32r-*-elf*
5046 Tsqware Sparclet sparclet-*-*
5047 NEC V850 w/simulator v850-*-*
5049 * New debugging protocols
5051 ARM with RDI protocol arm*-*-*
5052 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5053 DDB and LSI variants of PMON protocol mips*-*-*
5054 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5055 PowerPC with SDS protocol powerpc{,le}-*-eabi
5056 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5060 All configurations can now understand and use the DWARF 2 debugging
5061 format. The choice is automatic, if the symbol file contains DWARF 2
5066 GDB now includes basic Java language support. This support is
5067 only useful with Java compilers that produce native machine code.
5069 * solib-absolute-prefix and solib-search-path
5071 For SunOS and SVR4 shared libraries, you may now set the prefix for
5072 loading absolute shared library symbol files, and the search path for
5073 locating non-absolute shared library symbol files.
5075 * Live range splitting
5077 GDB can now effectively debug code for which GCC has performed live
5078 range splitting as part of its optimization. See gdb/doc/LRS for
5079 more details on the expected format of the stabs information.
5083 GDB's support for the GNU Hurd, including thread debugging, has been
5084 updated to work with current versions of the Hurd.
5088 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5089 instruction set. ARM GDB automatically detects when Thumb
5090 instructions are in use, and adjusts disassembly and backtracing
5095 GDB's MIPS target configurations now handle the MIP16 16-bit
5100 GDB now includes support for overlays; if an executable has been
5101 linked such that multiple sections are based at the same address, GDB
5102 will decide which section to use for symbolic info. You can choose to
5103 control the decision manually, using overlay commands, or implement
5104 additional target-side support and use "overlay load-target" to bring
5105 in the overlay mapping. Do "help overlay" for more detail.
5109 The command "info symbol <address>" displays information about
5110 the symbol at the specified address.
5114 The standard remote protocol now includes an extension that allows
5115 asynchronous collection and display of trace data. This requires
5116 extensive support in the target-side debugging stub. Tracing mode
5117 includes a new interaction mode in GDB and new commands: see the
5118 file tracepoint.c for more details.
5122 Configurations for embedded MIPS now include a simulator contributed
5123 by Cygnus Solutions. The simulator supports the instruction sets
5124 of most MIPS variants.
5128 Sparc configurations may now include the ERC32 simulator contributed
5129 by the European Space Agency. The simulator is not built into
5130 Sparc targets by default; configure with --enable-sim to include it.
5134 For target configurations that may include multiple variants of a
5135 basic architecture (such as MIPS and SH), you may now set the
5136 architecture explicitly. "set arch" sets, "info arch" lists
5137 the possible architectures.
5139 *** Changes in GDB-4.16:
5141 * New native configurations
5143 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5144 M68K NetBSD m68k-*-netbsd*
5145 PowerPC AIX 4.x powerpc-*-aix*
5146 PowerPC MacOS powerpc-*-macos*
5147 PowerPC Windows NT powerpcle-*-cygwin32
5148 RS/6000 AIX 4.x rs6000-*-aix4*
5152 ARM with RDP protocol arm-*-*
5153 I960 with MON960 i960-*-coff
5154 MIPS VxWorks mips*-*-vxworks*
5155 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5156 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5158 Matra Sparclet sparclet-*-*
5162 The powerpc-eabi configuration now includes the PSIM simulator,
5163 contributed by Andrew Cagney, with assistance from Mike Meissner.
5164 PSIM is a very elaborate model of the PowerPC, including not only
5165 basic instruction set execution, but also details of execution unit
5166 performance and I/O hardware. See sim/ppc/README for more details.
5170 GDB now works with Solaris 2.5.
5172 * Windows 95/NT native
5174 GDB will now work as a native debugger on Windows 95 and Windows NT.
5175 To build it from source, you must use the "gnu-win32" environment,
5176 which uses a DLL to emulate enough of Unix to run the GNU tools.
5177 Further information, binaries, and sources are available at
5178 ftp.cygnus.com, under pub/gnu-win32.
5180 * dont-repeat command
5182 If a user-defined command includes the command `dont-repeat', then the
5183 command will not be repeated if the user just types return. This is
5184 useful if the command is time-consuming to run, so that accidental
5185 extra keystrokes don't run the same command many times.
5187 * Send break instead of ^C
5189 The standard remote protocol now includes an option to send a break
5190 rather than a ^C to the target in order to interrupt it. By default,
5191 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5193 * Remote protocol timeout
5195 The standard remote protocol includes a new variable `remotetimeout'
5196 that allows you to set the number of seconds before GDB gives up trying
5197 to read from the target. The default value is 2.
5199 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5201 By default GDB will automatically keep track of objects as they are
5202 loaded and unloaded by the dynamic linker. By using the command `set
5203 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5204 when shared library events occur, thus allowing you to set breakpoints
5205 in shared libraries which are explicitly loaded by the inferior.
5207 Note this feature does not work on hpux8. On hpux9 you must link
5208 /usr/lib/end.o into your program. This feature should work
5209 automatically on hpux10.
5211 * Irix 5.x hardware watchpoint support
5213 Irix 5 configurations now support the use of hardware watchpoints.
5215 * Mips protocol "SYN garbage limit"
5217 When debugging a Mips target using the `target mips' protocol, you
5218 may set the number of characters that GDB will ignore by setting
5219 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5220 every character. The default value is 1050.
5222 * Recording and replaying remote debug sessions
5224 If you set `remotelogfile' to the name of a file, gdb will write to it
5225 a recording of a remote debug session. This recording may then be
5226 replayed back to gdb using "gdbreplay". See gdbserver/README for
5227 details. This is useful when you have a problem with GDB while doing
5228 remote debugging; you can make a recording of the session and send it
5229 to someone else, who can then recreate the problem.
5231 * Speedups for remote debugging
5233 GDB includes speedups for downloading and stepping MIPS systems using
5234 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5235 and more efficient S-record downloading.
5237 * Memory use reductions and statistics collection
5239 GDB now uses less memory and reports statistics about memory usage.
5240 Try the `maint print statistics' command, for example.
5242 *** Changes in GDB-4.15:
5244 * Psymtabs for XCOFF
5246 The symbol reader for AIX GDB now uses partial symbol tables. This
5247 can greatly improve startup time, especially for large executables.
5249 * Remote targets use caching
5251 Remote targets now use a data cache to speed up communication with the
5252 remote side. The data cache could lead to incorrect results because
5253 it doesn't know about volatile variables, thus making it impossible to
5254 debug targets which use memory mapped I/O devices. `set remotecache
5255 off' turns the the data cache off.
5257 * Remote targets may have threads
5259 The standard remote protocol now includes support for multiple threads
5260 in the target system, using new protocol commands 'H' and 'T'. See
5261 gdb/remote.c for details.
5265 If GDB is configured with `--enable-netrom', then it will include
5266 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5267 acts as though it is a bank of ROM on the target board, but you can
5268 write into it over the network. GDB's support consists only of
5269 support for fast loading into the emulated ROM; to debug, you must use
5270 another protocol, such as standard remote protocol. The usual
5271 sequence is something like
5273 target nrom <netrom-hostname>
5275 target remote <netrom-hostname>:1235
5279 GDB now includes support for the Apple Macintosh, as a host only. It
5280 may be run as either an MPW tool or as a standalone application, and
5281 it can debug through the serial port. All the usual GDB commands are
5282 available, but to the target command, you must supply "serial" as the
5283 device type instead of "/dev/ttyXX". See mpw-README in the main
5284 directory for more information on how to build. The MPW configuration
5285 scripts */mpw-config.in support only a few targets, and only the
5286 mips-idt-ecoff target has been tested.
5290 GDB configuration now uses autoconf. This is not user-visible,
5291 but does simplify configuration and building.
5295 GDB now supports hpux10.
5297 *** Changes in GDB-4.14:
5299 * New native configurations
5301 x86 FreeBSD i[345]86-*-freebsd
5302 x86 NetBSD i[345]86-*-netbsd
5303 NS32k NetBSD ns32k-*-netbsd
5304 Sparc NetBSD sparc-*-netbsd
5308 A29K VxWorks a29k-*-vxworks
5309 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5310 CPU32 EST-300 emulator m68*-*-est*
5311 PowerPC ELF powerpc-*-elf
5314 * Alpha OSF/1 support for procfs
5316 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5317 possible to attach to running processes. As the mounting of the /proc
5318 filesystem is optional on the Alpha, GDB automatically determines
5319 the availability of /proc during startup. This can lead to problems
5320 if /proc is unmounted after GDB has been started.
5322 * Arguments to user-defined commands
5324 User commands may accept up to 10 arguments separated by whitespace.
5325 Arguments are accessed within the user command via $arg0..$arg9. A
5328 print $arg0 + $arg1 + $arg2
5330 To execute the command use:
5333 Defines the command "adder" which prints the sum of its three arguments.
5334 Note the arguments are text substitutions, so they may reference variables,
5335 use complex expressions, or even perform inferior function calls.
5337 * New `if' and `while' commands
5339 This makes it possible to write more sophisticated user-defined
5340 commands. Both commands take a single argument, which is the
5341 expression to evaluate, and must be followed by the commands to
5342 execute, one per line, if the expression is nonzero, the list being
5343 terminated by the word `end'. The `if' command list may include an
5344 `else' word, which causes the following commands to be executed only
5345 if the expression is zero.
5347 * Fortran source language mode
5349 GDB now includes partial support for Fortran 77. It will recognize
5350 Fortran programs and can evaluate a subset of Fortran expressions, but
5351 variables and functions may not be handled correctly. GDB will work
5352 with G77, but does not yet know much about symbols emitted by other
5355 * Better HPUX support
5357 Most debugging facilities now work on dynamic executables for HPPAs
5358 running hpux9 or later. You can attach to running dynamically linked
5359 processes, but by default the dynamic libraries will be read-only, so
5360 for instance you won't be able to put breakpoints in them. To change
5361 that behavior do the following before running the program:
5367 This will cause the libraries to be mapped private and read-write.
5368 To revert to the normal behavior, do this:
5374 You cannot set breakpoints or examine data in the library until after
5375 the library is loaded if the function/data symbols do not have
5378 GDB can now also read debug symbols produced by the HP C compiler on
5379 HPPAs (sorry, no C++, Fortran or 68k support).
5381 * Target byte order now dynamically selectable
5383 You can choose which byte order to use with a target system, via the
5384 commands "set endian big" and "set endian little", and you can see the
5385 current setting by using "show endian". You can also give the command
5386 "set endian auto", in which case GDB will use the byte order
5387 associated with the executable. Currently, only embedded MIPS
5388 configurations support dynamic selection of target byte order.
5390 * New DOS host serial code
5392 This version uses DPMI interrupts to handle buffered I/O, so you
5393 no longer need to run asynctsr when debugging boards connected to
5396 *** Changes in GDB-4.13:
5398 * New "complete" command
5400 This lists all the possible completions for the rest of the line, if it
5401 were to be given as a command itself. This is intended for use by emacs.
5403 * Trailing space optional in prompt
5405 "set prompt" no longer adds a space for you after the prompt you set. This
5406 allows you to set a prompt which ends in a space or one that does not.
5408 * Breakpoint hit counts
5410 "info break" now displays a count of the number of times the breakpoint
5411 has been hit. This is especially useful in conjunction with "ignore"; you
5412 can ignore a large number of breakpoint hits, look at the breakpoint info
5413 to see how many times the breakpoint was hit, then run again, ignoring one
5414 less than that number, and this will get you quickly to the last hit of
5417 * Ability to stop printing at NULL character
5419 "set print null-stop" will cause GDB to stop printing the characters of
5420 an array when the first NULL is encountered. This is useful when large
5421 arrays actually contain only short strings.
5423 * Shared library breakpoints
5425 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5426 breakpoints in shared libraries before the executable is run.
5428 * Hardware watchpoints
5430 There is a new hardware breakpoint for the watch command for sparclite
5431 targets. See gdb/sparclite/hw_breakpoint.note.
5433 Hardware watchpoints are also now supported under GNU/Linux.
5437 Annotations have been added. These are for use with graphical interfaces,
5438 and are still experimental. Currently only gdba.el uses these.
5440 * Improved Irix 5 support
5442 GDB now works properly with Irix 5.2.
5444 * Improved HPPA support
5446 GDB now works properly with the latest GCC and GAS.
5448 * New native configurations
5450 Sequent PTX4 i[34]86-sequent-ptx4
5451 HPPA running OSF/1 hppa*-*-osf*
5452 Atari TT running SVR4 m68*-*-sysv4*
5453 RS/6000 LynxOS rs6000-*-lynxos*
5457 OS/9000 i[34]86-*-os9k
5458 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5461 * Hitachi SH7000 and E7000-PC ICE support
5463 There is now support for communicating with the Hitachi E7000-PC ICE.
5464 This is available automatically when GDB is configured for the SH.
5468 As usual, a variety of small fixes and improvements, both generic
5469 and configuration-specific. See the ChangeLog for more detail.
5471 *** Changes in GDB-4.12:
5473 * Irix 5 is now supported
5477 GDB-4.12 on the HPPA has a number of changes which make it unable
5478 to debug the output from the currently released versions of GCC and
5479 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5480 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5481 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5484 *** Changes in GDB-4.11:
5486 * User visible changes:
5490 The "set remotedebug" option is now consistent between the mips remote
5491 target, remote targets using the gdb-specific protocol, UDI (AMD's
5492 debug protocol for the 29k) and the 88k bug monitor. It is now an
5493 integer specifying a debug level (normally 0 or 1, but 2 means more
5494 debugging info for the mips target).
5496 * DEC Alpha native support
5498 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5499 debug info, but GDB works fairly well with the DEC compiler and should
5500 work with a future GCC release. See the README file for a few
5501 Alpha-specific notes.
5503 * Preliminary thread implementation
5505 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5507 * LynxOS native and target support for 386
5509 This release has been hosted on LynxOS 2.2, and also can be configured
5510 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5513 * Improvements in C++ mangling/demangling.
5515 This release has much better g++ debugging, specifically in name
5516 mangling/demangling, virtual function calls, print virtual table,
5517 call methods, ...etc.
5519 *** Changes in GDB-4.10:
5521 * User visible changes:
5523 Remote debugging using the GDB-specific (`target remote') protocol now
5524 supports the `load' command. This is only useful if you have some
5525 other way of getting the stub to the target system, and you can put it
5526 somewhere in memory where it won't get clobbered by the download.
5528 Filename completion now works.
5530 When run under emacs mode, the "info line" command now causes the
5531 arrow to point to the line specified. Also, "info line" prints
5532 addresses in symbolic form (as well as hex).
5534 All vxworks based targets now support a user settable option, called
5535 vxworks-timeout. This option represents the number of seconds gdb
5536 should wait for responses to rpc's. You might want to use this if
5537 your vxworks target is, perhaps, a slow software simulator or happens
5538 to be on the far side of a thin network line.
5542 This release contains support for using a DEC alpha as a GDB host for
5543 cross debugging. Native alpha debugging is not supported yet.
5546 *** Changes in GDB-4.9:
5550 This is the first GDB release which is accompanied by a matching testsuite.
5551 The testsuite requires installation of dejagnu, which should be available
5552 via ftp from most sites that carry GNU software.
5556 'Cfront' style demangling has had its name changed to 'ARM' style, to
5557 emphasize that it was written from the specifications in the C++ Annotated
5558 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5559 disclaimers, it still generated too much confusion with users attempting to
5560 use gdb with AT&T cfront.
5564 GDB now uses a standard remote interface to a simulator library.
5565 So far, the library contains simulators for the Zilog Z8001/2, the
5566 Hitachi H8/300, H8/500 and Super-H.
5568 * New targets supported
5570 H8/300 simulator h8300-hitachi-hms or h8300hms
5571 H8/500 simulator h8500-hitachi-hms or h8500hms
5572 SH simulator sh-hitachi-hms or sh
5573 Z8000 simulator z8k-zilog-none or z8ksim
5574 IDT MIPS board over serial line mips-idt-ecoff
5576 Cross-debugging to GO32 targets is supported. It requires a custom
5577 version of the i386-stub.c module which is integrated with the
5578 GO32 memory extender.
5580 * New remote protocols
5582 MIPS remote debugging protocol.
5584 * New source languages supported
5586 This version includes preliminary support for Chill, a Pascal like language
5587 used by telecommunications companies. Chill support is also being integrated
5588 into the GNU compiler, but we don't know when it will be publically available.
5591 *** Changes in GDB-4.8:
5593 * HP Precision Architecture supported
5595 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5596 version of this support was available as a set of patches from the
5597 University of Utah. GDB does not support debugging of programs
5598 compiled with the HP compiler, because HP will not document their file
5599 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5600 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5602 Many problems in the preliminary version have been fixed.
5604 * Faster and better demangling
5606 We have improved template demangling and fixed numerous bugs in the GNU style
5607 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5608 character types (wchar_t) are now supported. Demangling of each symbol is now
5609 only done once, and is cached when the symbol table for a file is read in.
5610 This results in a small increase in memory usage for C programs, a moderate
5611 increase in memory usage for C++ programs, and a fantastic speedup in
5614 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5615 from the specifications in the Annotated Reference Manual, which AT&T's
5616 compiler does not actually implement.
5618 * G++ multiple inheritance compiler problem
5620 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5621 inheritance lattices was reworked to properly discover ambiguities. We
5622 recently found an example which causes this new algorithm to fail in a
5623 very subtle way, producing bad debug information for those classes.
5624 The file 'gcc.patch' (in this directory) can be applied to gcc to
5625 circumvent the problem. A future GCC release will contain a complete
5628 The previous G++ debug info problem (mentioned below for the gdb-4.7
5629 release) is fixed in gcc version 2.3.2.
5631 * Improved configure script
5633 The `configure' script will now attempt to guess your system type if
5634 you don't supply a host system type. The old scheme of supplying a
5635 host system triplet is preferable over using this. All the magic is
5636 done in the new `config.guess' script. Examine it for details.
5638 We have also brought our configure script much more in line with the FSF's
5639 version. It now supports the --with-xxx options. In particular,
5640 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5641 The resulting GDB will not be able to read arbitrary object file formats --
5642 only the format ``expected'' to be used on the configured target system.
5643 We hope to make this the default in a future release.
5645 * Documentation improvements
5647 There's new internal documentation on how to modify GDB, and how to
5648 produce clean changes to the code. We implore people to read it
5649 before submitting changes.
5651 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5652 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5653 `info' files are also provided. To build `info' files from scratch,
5654 you will need the latest `makeinfo' release, which will be available in
5655 a future texinfo-X.Y release.
5657 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5658 We're not sure exactly which versions have this problem, but it has
5659 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5660 or better. If that isn't possible, there is a patch in
5661 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5662 around this problem.
5666 GDB now supports array constants that can be used in expressions typed in by
5667 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5668 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5671 The new directory `gdb/sparclite' contains a program that demonstrates
5672 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5674 * New native hosts supported
5676 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5677 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5679 * New targets supported
5681 AMD 29k family via UDI a29k-amd-udi or udi29k
5683 * New file formats supported
5685 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5686 HPUX core files, and SCO 3.2v2 core files.
5690 Attaching to processes now works again; thanks for the many bug reports.
5692 We have also stomped on a bunch of core dumps caused by
5693 printf_filtered("%s") problems.
5695 We eliminated a copyright problem on the rpc and ptrace header files
5696 for VxWorks, which was discovered at the last minute during the 4.7
5697 release. You should now be able to build a VxWorks GDB.
5699 You can now interrupt gdb while an attached process is running. This
5700 will cause the attached process to stop, and give control back to GDB.
5702 We fixed problems caused by using too many file descriptors
5703 for reading symbols from object files and libraries. This was
5704 especially a problem for programs that used many (~100) shared
5707 The `step' command now only enters a subroutine if there is line number
5708 information for the subroutine. Otherwise it acts like the `next'
5709 command. Previously, `step' would enter subroutines if there was
5710 any debugging information about the routine. This avoids problems
5711 when using `cc -g1' on MIPS machines.
5713 * Internal improvements
5715 GDB's internal interfaces have been improved to make it easier to support
5716 debugging of multiple languages in the future.
5718 GDB now uses a common structure for symbol information internally.
5719 Minimal symbols (derived from linkage symbols in object files), partial
5720 symbols (from a quick scan of debug information), and full symbols
5721 contain a common subset of information, making it easier to write
5722 shared code that handles any of them.
5724 * New command line options
5726 We now accept --silent as an alias for --quiet.
5730 The memory-mapped-malloc library is now licensed under the GNU Library
5731 General Public License.
5733 *** Changes in GDB-4.7:
5735 * Host/native/target split
5737 GDB has had some major internal surgery to untangle the support for
5738 hosts and remote targets. Now, when you configure GDB for a remote
5739 target, it will no longer load in all of the support for debugging
5740 local programs on the host. When fully completed and tested, this will
5741 ensure that arbitrary host/target combinations are possible.
5743 The primary conceptual shift is to separate the non-portable code in
5744 GDB into three categories. Host specific code is required any time GDB
5745 is compiled on that host, regardless of the target. Target specific
5746 code relates to the peculiarities of the target, but can be compiled on
5747 any host. Native specific code is everything else: it can only be
5748 built when the host and target are the same system. Child process
5749 handling and core file support are two common `native' examples.
5751 GDB's use of /proc for controlling Unix child processes is now cleaner.
5752 It has been split out into a single module under the `target_ops' vector,
5753 plus two native-dependent functions for each system that uses /proc.
5755 * New hosts supported
5757 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5758 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5759 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5761 * New targets supported
5763 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5764 68030 and CPU32 m68030-*-*, m68332-*-*
5766 * New native hosts supported
5768 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5769 (386bsd is not well tested yet)
5770 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5772 * New file formats supported
5774 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5775 supports reading of `a.out.adobe' object files, which are an a.out
5776 format extended with minimal information about multiple sections.
5780 `show copying' is the same as the old `info copying'.
5781 `show warranty' is the same as `info warrantee'.
5782 These were renamed for consistency. The old commands continue to work.
5784 `info handle' is a new alias for `info signals'.
5786 You can now define pre-command hooks, which attach arbitrary command
5787 scripts to any command. The commands in the hook will be executed
5788 prior to the user's command. You can also create a hook which will be
5789 executed whenever the program stops. See gdb.texinfo.
5793 We now deal with Cfront style name mangling, and can even extract type
5794 info from mangled symbols. GDB can automatically figure out which
5795 symbol mangling style your C++ compiler uses.
5797 Calling of methods and virtual functions has been improved as well.
5801 The crash that occured when debugging Sun Ansi-C compiled binaries is
5802 fixed. This was due to mishandling of the extra N_SO stabs output
5805 We also finally got Ultrix 4.2 running in house, and fixed core file
5806 support, with help from a dozen people on the net.
5808 John M. Farrell discovered that the reason that single-stepping was so
5809 slow on all of the Mips based platforms (primarily SGI and DEC) was
5810 that we were trying to demangle and lookup a symbol used for internal
5811 purposes on every instruction that was being stepped through. Changing
5812 the name of that symbol so that it couldn't be mistaken for a C++
5813 mangled symbol sped things up a great deal.
5815 Rich Pixley sped up symbol lookups in general by getting much smarter
5816 about when C++ symbol mangling is necessary. This should make symbol
5817 completion (TAB on the command line) much faster. It's not as fast as
5818 we'd like, but it's significantly faster than gdb-4.6.
5822 A new user controllable variable 'call_scratch_address' can
5823 specify the location of a scratch area to be used when GDB
5824 calls a function in the target. This is necessary because the
5825 usual method of putting the scratch area on the stack does not work
5826 in systems that have separate instruction and data spaces.
5828 We integrated changes to support the 29k UDI (Universal Debugger
5829 Interface), but discovered at the last minute that we didn't have all
5830 of the appropriate copyright paperwork. We are working with AMD to
5831 resolve this, and hope to have it available soon.
5835 We have sped up the remote serial line protocol, especially for targets
5836 with lots of registers. It now supports a new `expedited status' ('T')
5837 message which can be used in place of the existing 'S' status message.
5838 This allows the remote stub to send only the registers that GDB
5839 needs to make a quick decision about single-stepping or conditional
5840 breakpoints, eliminating the need to fetch the entire register set for
5841 each instruction being stepped through.
5843 The GDB remote serial protocol now implements a write-through cache for
5844 registers, only re-reading the registers if the target has run.
5846 There is also a new remote serial stub for SPARC processors. You can
5847 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5848 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5849 processor with a serial port.
5853 Configure.in files have become much easier to read and modify. A new
5854 `table driven' format makes it more obvious what configurations are
5855 supported, and what files each one uses.
5859 There is a new opcodes library which will eventually contain all of the
5860 disassembly routines and opcode tables. At present, it only contains
5861 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5862 disassembler (binutils/objdump) to share these routines.
5864 The libiberty library is now copylefted under the GNU Library General
5865 Public License. This allows more liberal use, and was done so libg++
5866 can use it. This makes no difference to GDB, since the Library License
5867 grants all the rights from the General Public License.
5871 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5872 reference to the stabs symbol info used by the debugger. It is (as far
5873 as we know) the only published document on this fascinating topic. We
5874 encourage you to read it, compare it to the stabs information on your
5875 system, and send improvements on the document in general (to
5876 bug-gdb@prep.ai.mit.edu).
5878 And, of course, many bugs have been fixed.
5881 *** Changes in GDB-4.6:
5883 * Better support for C++ function names
5885 GDB now accepts as input the "demangled form" of C++ overloaded function
5886 names and member function names, and can do command completion on such names
5887 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5888 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5889 Make use of command completion, it is your friend.
5891 GDB also now accepts a variety of C++ mangled symbol formats. They are
5892 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5893 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5894 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5895 for the list of formats.
5897 * G++ symbol mangling problem
5899 Recent versions of gcc have a bug in how they emit debugging information for
5900 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5901 directory) can be applied to gcc to fix the problem. Alternatively, if you
5902 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5903 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5904 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5907 * New 'maintenance' command
5909 All of the commands related to hacking GDB internals have been moved out of
5910 the main command set, and now live behind the 'maintenance' command. This
5911 can also be abbreviated as 'mt'. The following changes were made:
5913 dump-me -> maintenance dump-me
5914 info all-breakpoints -> maintenance info breakpoints
5915 printmsyms -> maintenance print msyms
5916 printobjfiles -> maintenance print objfiles
5917 printpsyms -> maintenance print psymbols
5918 printsyms -> maintenance print symbols
5920 The following commands are new:
5922 maintenance demangle Call internal GDB demangler routine to
5923 demangle a C++ link name and prints the result.
5924 maintenance print type Print a type chain for a given symbol
5926 * Change to .gdbinit file processing
5928 We now read the $HOME/.gdbinit file before processing the argv arguments
5929 (e.g. reading symbol files or core files). This allows global parameters to
5930 be set, which will apply during the symbol reading. The ./.gdbinit is still
5931 read after argv processing.
5933 * New hosts supported
5935 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5937 GNU/Linux support i386-unknown-linux or linux
5939 We are also including code to support the HP/PA running BSD and HPUX. This
5940 is almost guaranteed not to work, as we didn't have time to test or build it
5941 for this release. We are including it so that the more adventurous (or
5942 masochistic) of you can play with it. We also had major problems with the
5943 fact that the compiler that we got from HP doesn't support the -g option.
5946 * New targets supported
5948 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5950 * More smarts about finding #include files
5952 GDB now remembers the compilation directory for all include files, and for
5953 all files from which C is generated (like yacc and lex sources). This
5954 greatly improves GDB's ability to find yacc/lex sources, and include files,
5955 especially if you are debugging your program from a directory different from
5956 the one that contains your sources.
5958 We also fixed a bug which caused difficulty with listing and setting
5959 breakpoints in include files which contain C code. (In the past, you had to
5960 try twice in order to list an include file that you hadn't looked at before.)
5962 * Interesting infernals change
5964 GDB now deals with arbitrary numbers of sections, where the symbols for each
5965 section must be relocated relative to that section's landing place in the
5966 target's address space. This work was needed to support ELF with embedded
5967 stabs used by Solaris-2.0.
5969 * Bug fixes (of course!)
5971 There have been loads of fixes for the following things:
5972 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5973 i960, stabs, DOS(GO32), procfs, etc...
5975 See the ChangeLog for details.
5977 *** Changes in GDB-4.5:
5979 * New machines supported (host and target)
5981 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5983 SGI Irix-4.x mips-sgi-irix4 or iris4
5985 * New malloc package
5987 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5988 Mmalloc is capable of handling mutiple heaps of memory. It is also
5989 capable of saving a heap to a file, and then mapping it back in later.
5990 This can be used to greatly speedup the startup of GDB by using a
5991 pre-parsed symbol table which lives in a mmalloc managed heap. For
5992 more details, please read mmalloc/mmalloc.texi.
5996 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5997 'help info proc' for details.
5999 * MIPS ecoff symbol table format
6001 The code that reads MIPS symbol table format is now supported on all hosts.
6002 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6005 * File name changes for MS-DOS
6007 Many files in the config directories have been renamed to make it easier to
6008 support GDB on MS-DOSe systems (which have very restrictive file name
6009 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6010 environment) is close to working but has some remaining problems. Note
6011 that debugging of DOS programs is not supported, due to limitations
6012 in the ``operating system'', but it can be used to host cross-debugging.
6014 * Cross byte order fixes
6016 Many fixes have been made to support cross debugging of Sparc and MIPS
6017 targets from hosts whose byte order differs.
6019 * New -mapped and -readnow options
6021 If memory-mapped files are available on your system through the 'mmap'
6022 system call, you can use the -mapped option on the `file' or
6023 `symbol-file' commands to cause GDB to write the symbols from your
6024 program into a reusable file. If the program you are debugging is
6025 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6026 Future GDB debugging sessions will notice the presence of this file,
6027 and will quickly map in symbol information from it, rather than reading
6028 the symbol table from the executable program. Using the '-mapped'
6029 option in a GDB `file' or `symbol-file' command has the same effect as
6030 starting GDB with the '-mapped' command-line option.
6032 You can cause GDB to read the entire symbol table immediately by using
6033 the '-readnow' option with any of the commands that load symbol table
6034 information (or on the GDB command line). This makes the command
6035 slower, but makes future operations faster.
6037 The -mapped and -readnow options are typically combined in order to
6038 build a `fred.syms' file that contains complete symbol information.
6039 A simple GDB invocation to do nothing but build a `.syms' file for future
6042 gdb -batch -nx -mapped -readnow programname
6044 The `.syms' file is specific to the host machine on which GDB is run.
6045 It holds an exact image of GDB's internal symbol table. It cannot be
6046 shared across multiple host platforms.
6048 * longjmp() handling
6050 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6051 siglongjmp() without losing control. This feature has not yet been ported to
6052 all systems. It currently works on many 386 platforms, all MIPS-based
6053 platforms (SGI, DECstation, etc), and Sun3/4.
6057 Preliminary work has been put in to support the new Solaris OS from Sun. At
6058 this time, it can control and debug processes, but it is not capable of
6063 As always, many many bug fixes. The major areas were with g++, and mipsread.
6064 People using the MIPS-based platforms should experience fewer mysterious
6065 crashes and trashed symbol tables.
6067 *** Changes in GDB-4.4:
6069 * New machines supported (host and target)
6071 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6073 BSD Reno on Vax vax-dec-bsd
6074 Ultrix on Vax vax-dec-ultrix
6076 * New machines supported (target)
6078 AMD 29000 embedded, using EBMON a29k-none-none
6082 GDB continues to improve its handling of C++. `References' work better.
6083 The demangler has also been improved, and now deals with symbols mangled as
6084 per the Annotated C++ Reference Guide.
6086 GDB also now handles `stabs' symbol information embedded in MIPS
6087 `ecoff' symbol tables. Since the ecoff format was not easily
6088 extensible to handle new languages such as C++, this appeared to be a
6089 good way to put C++ debugging info into MIPS binaries. This option
6090 will be supported in the GNU C compiler, version 2, when it is
6093 * New features for SVR4
6095 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6096 shared libraries. Debugging dynamically linked programs should present
6097 only minor differences from debugging statically linked programs.
6099 The `info proc' command will print out information about any process
6100 on an SVR4 system (including the one you are debugging). At the moment,
6101 it prints the address mappings of the process.
6103 If you bring up GDB on another SVR4 system, please send mail to
6104 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6106 * Better dynamic linking support in SunOS
6108 Reading symbols from shared libraries which contain debugging symbols
6109 now works properly. However, there remain issues such as automatic
6110 skipping of `transfer vector' code during function calls, which
6111 make it harder to debug code in a shared library, than to debug the
6112 same code linked statically.
6116 GDB is now using the latest `getopt' routines from the FSF. This
6117 version accepts the -- prefix for options with long names. GDB will
6118 continue to accept the old forms (-option and +option) as well.
6119 Various single letter abbreviations for options have been explicity
6120 added to the option table so that they won't get overshadowed in the
6121 future by other options that begin with the same letter.
6125 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6126 Many assorted bugs have been handled. Many more remain to be handled.
6127 See the various ChangeLog files (primarily in gdb and bfd) for details.
6130 *** Changes in GDB-4.3:
6132 * New machines supported (host and target)
6134 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6135 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6136 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6138 * Almost SCO Unix support
6140 We had hoped to support:
6141 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6142 (except for core file support), but we discovered very late in the release
6143 that it has problems with process groups that render gdb unusable. Sorry
6144 about that. I encourage people to fix it and post the fixes.
6146 * Preliminary ELF and DWARF support
6148 GDB can read ELF object files on System V Release 4, and can handle
6149 debugging records for C, in DWARF format, in ELF files. This support
6150 is preliminary. If you bring up GDB on another SVR4 system, please
6151 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6156 GDB now uses the latest `readline' library. One user-visible change
6157 is that two tabs will list possible command completions, which previously
6158 required typing M-? (meta-question mark, or ESC ?).
6162 The `stepi' bug that many of you noticed has been squashed.
6163 Many bugs in C++ have been handled. Many more remain to be handled.
6164 See the various ChangeLog files (primarily in gdb and bfd) for details.
6166 * State of the MIPS world (in case you wondered):
6168 GDB can understand the symbol tables emitted by the compilers
6169 supplied by most vendors of MIPS-based machines, including DEC. These
6170 symbol tables are in a format that essentially nobody else uses.
6172 Some versions of gcc come with an assembler post-processor called
6173 mips-tfile. This program is required if you want to do source-level
6174 debugging of gcc-compiled programs. I believe FSF does not ship
6175 mips-tfile with gcc version 1, but it will eventually come with gcc
6178 Debugging of g++ output remains a problem. g++ version 1.xx does not
6179 really support it at all. (If you're lucky, you should be able to get
6180 line numbers and stack traces to work, but no parameters or local
6181 variables.) With some work it should be possible to improve the
6184 When gcc version 2 is released, you will have somewhat better luck.
6185 However, even then you will get confusing results for inheritance and
6188 We will eventually provide full debugging of g++ output on
6189 DECstations. This will probably involve some kind of stabs-in-ecoff
6190 encapulation, but the details have not been worked out yet.
6193 *** Changes in GDB-4.2:
6195 * Improved configuration
6197 Only one copy of `configure' exists now, and it is not self-modifying.
6198 Porting BFD is simpler.
6202 The `step' and `next' commands now only stop at the first instruction
6203 of a source line. This prevents the multiple stops that used to occur
6204 in switch statements, for-loops, etc. `Step' continues to stop if a
6205 function that has debugging information is called within the line.
6209 Lots of small bugs fixed. More remain.
6211 * New host supported (not target)
6213 Intel 386 PC clone running Mach i386-none-mach
6216 *** Changes in GDB-4.1:
6218 * Multiple source language support
6220 GDB now has internal scaffolding to handle several source languages.
6221 It determines the type of each source file from its filename extension,
6222 and will switch expression parsing and number formatting to match the
6223 language of the function in the currently selected stack frame.
6224 You can also specifically set the language to be used, with
6225 `set language c' or `set language modula-2'.
6229 GDB now has preliminary support for the GNU Modula-2 compiler,
6230 currently under development at the State University of New York at
6231 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6232 continue through the fall of 1991 and into 1992.
6234 Other Modula-2 compilers are currently not supported, and attempting to
6235 debug programs compiled with them will likely result in an error as the
6236 symbol table is read. Feel free to work on it, though!
6238 There are hooks in GDB for strict type checking and range checking,
6239 in the `Modula-2 philosophy', but they do not currently work.
6243 GDB can now write to executable and core files (e.g. patch
6244 a variable's value). You must turn this switch on, specify
6245 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6246 by assigning a new value to a variable. Modifications take
6249 * Automatic SunOS shared library reading
6251 When you run your program, GDB automatically determines where its
6252 shared libraries (if any) have been loaded, and reads their symbols.
6253 The `share' command is no longer needed. This also works when
6254 examining core files.
6258 You can specify the number of lines that the `list' command shows.
6261 * New machines supported (host and target)
6263 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6264 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6265 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6267 * New hosts supported (not targets)
6269 IBM RT/PC: romp-ibm-aix or rtpc
6271 * New targets supported (not hosts)
6273 AMD 29000 embedded with COFF a29k-none-coff
6274 AMD 29000 embedded with a.out a29k-none-aout
6275 Ultracomputer remote kernel debug a29k-nyu-kern
6277 * New remote interfaces
6283 *** Changes in GDB-4.0:
6287 Wide output is wrapped at good places to make the output more readable.
6289 Gdb now supports cross-debugging from a host machine of one type to a
6290 target machine of another type. Communication with the target system
6291 is over serial lines. The ``target'' command handles connecting to the
6292 remote system; the ``load'' command will download a program into the
6293 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6294 also supports debugging of realtime processes running under VxWorks,
6295 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6296 stub on the target system.
6298 New CPUs supported include the AMD 29000 and Intel 960.
6300 GDB now reads object files and symbol tables via a ``binary file''
6301 library, which allows a single copy of GDB to debug programs of multiple
6302 object file types such as a.out and coff.
6304 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6305 refcard.dvi and refcard.ps are available to format it).
6308 * Control-Variable user interface simplified
6310 All variables that control the operation of the debugger can be set
6311 by the ``set'' command, and displayed by the ``show'' command.
6313 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6314 ``Show prompt'' produces the response:
6315 Gdb's prompt is new-gdb=>.
6317 What follows are the NEW set commands. The command ``help set'' will
6318 print a complete list of old and new set commands. ``help set FOO''
6319 will give a longer description of the variable FOO. ``show'' will show
6320 all of the variable descriptions and their current settings.
6322 confirm on/off: Enables warning questions for operations that are
6323 hard to recover from, e.g. rerunning the program while
6324 it is already running. Default is ON.
6326 editing on/off: Enables EMACS style command line editing
6327 of input. Previous lines can be recalled with
6328 control-P, the current line can be edited with control-B,
6329 you can search for commands with control-R, etc.
6332 history filename NAME: NAME is where the gdb command history
6333 will be stored. The default is .gdb_history,
6334 or the value of the environment variable
6337 history size N: The size, in commands, of the command history. The
6338 default is 256, or the value of the environment variable
6341 history save on/off: If this value is set to ON, the history file will
6342 be saved after exiting gdb. If set to OFF, the
6343 file will not be saved. The default is OFF.
6345 history expansion on/off: If this value is set to ON, then csh-like
6346 history expansion will be performed on
6347 command line input. The default is OFF.
6349 radix N: Sets the default radix for input and output. It can be set
6350 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6351 in the current radix, so "set radix 10" is always a no-op.
6353 height N: This integer value is the number of lines on a page. Default
6354 is 24, the current `stty rows'' setting, or the ``li#''
6355 setting from the termcap entry matching the environment
6358 width N: This integer value is the number of characters on a line.
6359 Default is 80, the current `stty cols'' setting, or the ``co#''
6360 setting from the termcap entry matching the environment
6363 Note: ``set screensize'' is obsolete. Use ``set height'' and
6364 ``set width'' instead.
6366 print address on/off: Print memory addresses in various command displays,
6367 such as stack traces and structure values. Gdb looks
6368 more ``symbolic'' if you turn this off; it looks more
6369 ``machine level'' with it on. Default is ON.
6371 print array on/off: Prettyprint arrays. New convenient format! Default
6374 print demangle on/off: Print C++ symbols in "source" form if on,
6377 print asm-demangle on/off: Same, for assembler level printouts
6380 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6383 * Support for Epoch Environment.
6385 The epoch environment is a version of Emacs v18 with windowing. One
6386 new command, ``inspect'', is identical to ``print'', except that if you
6387 are running in the epoch environment, the value is printed in its own
6391 * Support for Shared Libraries
6393 GDB can now debug programs and core files that use SunOS shared libraries.
6394 Symbols from a shared library cannot be referenced
6395 before the shared library has been linked with the program (this
6396 happens after you type ``run'' and before the function main() is entered).
6397 At any time after this linking (including when examining core files
6398 from dynamically linked programs), gdb reads the symbols from each
6399 shared library when you type the ``sharedlibrary'' command.
6400 It can be abbreviated ``share''.
6402 sharedlibrary REGEXP: Load shared object library symbols for files
6403 matching a unix regular expression. No argument
6404 indicates to load symbols for all shared libraries.
6406 info sharedlibrary: Status of loaded shared libraries.
6411 A watchpoint stops execution of a program whenever the value of an
6412 expression changes. Checking for this slows down execution
6413 tremendously whenever you are in the scope of the expression, but is
6414 quite useful for catching tough ``bit-spreader'' or pointer misuse
6415 problems. Some machines such as the 386 have hardware for doing this
6416 more quickly, and future versions of gdb will use this hardware.
6418 watch EXP: Set a watchpoint (breakpoint) for an expression.
6420 info watchpoints: Information about your watchpoints.
6422 delete N: Deletes watchpoint number N (same as breakpoints).
6423 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6424 enable N: Re-enables watchpoint number N (same as breakpoints).
6427 * C++ multiple inheritance
6429 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6432 * C++ exception handling
6434 Gdb now supports limited C++ exception handling. Besides the existing
6435 ability to breakpoint on an exception handler, gdb can breakpoint on
6436 the raising of an exception (before the stack is peeled back to the
6439 catch FOO: If there is a FOO exception handler in the dynamic scope,
6440 set a breakpoint to catch exceptions which may be raised there.
6441 Multiple exceptions (``catch foo bar baz'') may be caught.
6443 info catch: Lists all exceptions which may be caught in the
6444 current stack frame.
6447 * Minor command changes
6449 The command ``call func (arg, arg, ...)'' now acts like the print
6450 command, except it does not print or save a value if the function's result
6451 is void. This is similar to dbx usage.
6453 The ``up'' and ``down'' commands now always print the frame they end up
6454 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6455 frames without printing.
6457 * New directory command
6459 'dir' now adds directories to the FRONT of the source search path.
6460 The path starts off empty. Source files that contain debug information
6461 about the directory in which they were compiled can be found even
6462 with an empty path; Sun CC and GCC include this information. If GDB can't
6463 find your source file in the current directory, type "dir .".
6465 * Configuring GDB for compilation
6467 For normal use, type ``./configure host''. See README or gdb.texinfo
6470 GDB now handles cross debugging. If you are remotely debugging between
6471 two different machines, type ``./configure host -target=targ''.
6472 Host is the machine where GDB will run; targ is the machine
6473 where the program that you are debugging will run.
projects / external / binutils.git / blob