1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.11
6 * New Python-based convenience function $_as_string(val), which returns
7 the textual representation of a value. This function is especially
8 useful to obtain the text label of an enum value.
10 * Intel MPX bound violation handling.
12 Segmentation faults caused by a Intel MPX boundary violation
13 now display the kind of violation (upper or lower), the memory
14 address accessed and the memory bounds, along with the usual
15 signal received and code location.
19 Program received signal SIGSEGV, Segmentation fault
20 Upper bound violation while accessing address 0x7fffffffc3b3
21 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
22 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
27 skip -gfile file-glob-pattern
28 skip -function function
29 skip -rfunction regular-expression
30 A generalized form of the skip command, with new support for
31 glob-style file names and regular expressions for function names.
32 Additionally, a file spec and a function spec may now be combined.
34 *** Changes in GDB 7.11
36 * GDB now supports debugging kernel-based threads on FreeBSD.
38 * Per-inferior thread numbers
40 Thread numbers are now per inferior instead of global. If you're
41 debugging multiple inferiors, GDB displays thread IDs using a
42 qualified INF_NUM.THR_NUM form. For example:
46 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
47 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
48 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
49 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
51 As consequence, thread numbers as visible in the $_thread
52 convenience variable and in Python's InferiorThread.num attribute
53 are no longer unique between inferiors.
55 GDB now maintains a second thread ID per thread, referred to as the
56 global thread ID, which is the new equivalent of thread numbers in
57 previous releases. See also $_gthread below.
59 For backwards compatibility, MI's thread IDs always refer to global
62 * Commands that accept thread IDs now accept the qualified
63 INF_NUM.THR_NUM form as well. For example:
66 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
69 * In commands that accept a list of thread IDs, you can now refer to
70 all threads of an inferior using a star wildcard. GDB accepts
71 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
72 refer to all threads of the current inferior. For example, "info
75 * You can use "info threads -gid" to display the global thread ID of
78 * The new convenience variable $_gthread holds the global number of
81 * The new convenience variable $_inferior holds the number of the
84 * GDB now displays the ID and name of the thread that hit a breakpoint
85 or received a signal, if your program is multi-threaded. For
88 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
89 Thread 1 "main" received signal SIGINT, Interrupt.
91 * Record btrace now supports non-stop mode.
93 * Support for tracepoints on aarch64-linux was added in GDBserver.
95 * The 'record instruction-history' command now indicates speculative execution
96 when using the Intel Processor Trace recording format.
98 * GDB now allows users to specify explicit locations, bypassing
99 the linespec parser. This feature is also available to GDB/MI
102 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
103 GDB now is able to debug both AArch64 applications and ARM applications
106 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
107 including JIT compiling fast tracepoint's conditional expression bytecode
110 * GDB now supports displaced stepping on AArch64 GNU/Linux.
112 * "info threads", "info inferiors", "info display", "info checkpoints"
113 and "maint info program-spaces" now list the corresponding items in
114 ascending ID order, for consistency with all other "info" commands.
116 * In Ada, the overloads selection menu has been enhanced to display the
117 parameter types and the return types for the matching overloaded subprograms.
121 maint set target-non-stop (on|off|auto)
122 maint show target-non-stop
123 Control whether GDB targets always operate in non-stop mode even if
124 "set non-stop" is "off". The default is "auto", meaning non-stop
125 mode is enabled if supported by the target.
127 maint set bfd-sharing
128 maint show bfd-sharing
129 Control the reuse of bfd objects.
133 Control display of debugging info regarding bfd caching.
137 Control display of debugging info regarding FreeBSD threads.
139 set remote multiprocess-extensions-packet
140 show remote multiprocess-extensions-packet
141 Set/show the use of the remote protocol multiprocess extensions.
143 set remote thread-events
144 show remote thread-events
145 Set/show the use of thread create/exit events.
147 set ada print-signatures on|off
148 show ada print-signatures"
149 Control whether parameter types and return types are displayed in overloads
150 selection menus. It is activaled (@code{on}) by default.
154 Controls the maximum size of memory, in bytes, that GDB will
155 allocate for value contents. Prevents incorrect programs from
156 causing GDB to allocate overly large buffers. Default is 64k.
158 * The "disassemble" command accepts a new modifier: /s.
159 It prints mixed source+disassembly like /m with two differences:
160 - disassembled instructions are now printed in program order, and
161 - and source for all relevant files is now printed.
162 The "/m" option is now considered deprecated: its "source-centric"
163 output hasn't proved useful in practice.
165 * The "record instruction-history" command accepts a new modifier: /s.
166 It behaves exactly like /m and prints mixed source+disassembly.
168 * The "set scheduler-locking" command supports a new mode "replay".
169 It behaves like "off" in record mode and like "on" in replay mode.
171 * Support for various ROM monitors has been removed:
173 target dbug dBUG ROM monitor for Motorola ColdFire
174 target picobug Motorola picobug monitor
175 target dink32 DINK32 ROM monitor for PowerPC
176 target m32r Renesas M32R/D ROM monitor
177 target mon2000 mon2000 ROM monitor
178 target ppcbug PPCBUG ROM monitor for PowerPC
180 * Support for reading/writing memory and extracting values on architectures
181 whose memory is addressable in units of any integral multiple of 8 bits.
186 Indicates that an exec system call was executed.
188 exec-events feature in qSupported
189 The qSupported packet allows GDB to request support for exec
190 events using the new 'gdbfeature' exec-event, and the qSupported
191 response can contain the corresponding 'stubfeature'. Set and
192 show commands can be used to display whether these features are enabled.
195 Equivalent to interrupting with the ^C character, but works in
198 thread created stop reason (T05 create:...)
199 Indicates that the thread was just created and is stopped at entry.
201 thread exit stop reply (w exitcode;tid)
202 Indicates that the thread has terminated.
205 Enables/disables thread create and exit event reporting. For
206 example, this is used in non-stop mode when GDB stops a set of
207 threads and synchronously waits for the their corresponding stop
208 replies. Without exit events, if one of the threads exits, GDB
209 would hang forever not knowing that it should no longer expect a
210 stop for that same thread.
214 Indicates that there are no resumed threads left in the target (all
215 threads are stopped). The remote stub reports support for this stop
216 reply to GDB's qSupported query.
218 QCatchSyscalls:1 [;SYSNO]...
220 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
221 catching syscalls from the inferior process.
223 syscall_entry stop reason
224 Indicates that a syscall was just called.
226 syscall_return stop reason
227 Indicates that a syscall just returned.
229 QCatchSyscalls:1 in qSupported
230 The qSupported packet may now include QCatchSyscalls:1 in the reply
231 to indicate support for catching syscalls.
233 * Extended-remote exec events
235 ** GDB now has support for exec events on extended-remote Linux targets.
236 For such targets with Linux kernels 2.5.46 and later, this enables
237 follow-exec-mode and exec catchpoints.
239 set remote exec-event-feature-packet
240 show remote exec-event-feature-packet
241 Set/show the use of the remote exec event feature.
243 * Thread names in remote protocol
245 The reply to qXfer:threads:read may now include a name attribute for each
248 * Target remote mode fork and exec events
250 ** GDB now has support for fork and exec events on target remote mode
251 Linux targets. For such targets with Linux kernels 2.5.46 and later,
252 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
253 fork and exec catchpoints.
255 * Remote syscall events
257 ** GDB now has support for catch syscall on remote Linux targets,
258 currently enabled on x86/x86_64 architectures.
260 set remote catch-syscall-packet
261 show remote catch-syscall-packet
262 Set/show the use of the remote catch syscall feature.
266 ** The -var-set-format command now accepts the zero-hexadecimal
267 format. It outputs data in hexadecimal format with zero-padding on the
272 ** gdb.InferiorThread objects have a new attribute "global_num",
273 which refers to the thread's global thread ID. The existing
274 "num" attribute now refers to the thread's per-inferior number.
275 See "Per-inferior thread numbers" above.
276 ** gdb.InferiorThread objects have a new attribute "inferior", which
277 is the Inferior object the thread belongs to.
279 *** Changes in GDB 7.10
281 * Support for process record-replay and reverse debugging on aarch64*-linux*
282 targets has been added. GDB now supports recording of A64 instruction set
283 including advance SIMD instructions.
285 * Support for Sun's version of the "stabs" debug file format has been removed.
287 * GDB now honors the content of the file /proc/PID/coredump_filter
288 (PID is the process ID) on GNU/Linux systems. This file can be used
289 to specify the types of memory mappings that will be included in a
290 corefile. For more information, please refer to the manual page of
291 "core(5)". GDB also has a new command: "set use-coredump-filter
292 on|off". It allows to set whether GDB will read the content of the
293 /proc/PID/coredump_filter file when generating a corefile.
295 * The "info os" command on GNU/Linux can now display information on
297 "info os cpus" Listing of all cpus/cores on the system
299 * GDB has two new commands: "set serial parity odd|even|none" and
300 "show serial parity". These allows to set or show parity for the
303 * The "info source" command now displays the producer string if it was
304 present in the debug info. This typically includes the compiler version
305 and may include things like its command line arguments.
307 * The "info dll", an alias of the "info sharedlibrary" command,
308 is now available on all platforms.
310 * Directory names supplied to the "set sysroot" commands may be
311 prefixed with "target:" to tell GDB to access shared libraries from
312 the target system, be it local or remote. This replaces the prefix
313 "remote:". The default sysroot has been changed from "" to
314 "target:". "remote:" is automatically converted to "target:" for
315 backward compatibility.
317 * The system root specified by "set sysroot" will be prepended to the
318 filename of the main executable (if reported to GDB as absolute by
319 the operating system) when starting processes remotely, and when
320 attaching to already-running local or remote processes.
322 * GDB now supports automatic location and retrieval of executable
323 files from remote targets. Remote debugging can now be initiated
324 using only a "target remote" or "target extended-remote" command
325 (no "set sysroot" or "file" commands are required). See "New remote
328 * The "dump" command now supports verilog hex format.
330 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
332 * On GNU/Linux, GDB and gdbserver are now able to access executable
333 and shared library files without a "set sysroot" command when
334 attaching to processes running in different mount namespaces from
335 the debugger. This makes it possible to attach to processes in
336 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
337 See "New remote packets" below.
339 * The "tui reg" command now provides completion for all of the
340 available register groups, including target specific groups.
342 * The HISTSIZE environment variable is no longer read when determining
343 the size of GDB's command history. GDB now instead reads the dedicated
344 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
345 disables truncation of command history. Non-numeric values of GDBHISTSIZE
350 ** Memory ports can now be unbuffered.
354 ** gdb.Objfile objects have a new attribute "username",
355 which is the name of the objfile as specified by the user,
356 without, for example, resolving symlinks.
357 ** You can now write frame unwinders in Python.
358 ** gdb.Type objects have a new method "optimized_out",
359 returning optimized out gdb.Value instance of this type.
360 ** gdb.Value objects have new methods "reference_value" and
361 "const_value" which return a reference to the value and a
362 "const" version of the value respectively.
366 maint print symbol-cache
367 Print the contents of the symbol cache.
369 maint print symbol-cache-statistics
370 Print statistics of symbol cache usage.
372 maint flush-symbol-cache
373 Flush the contents of the symbol cache.
377 Start branch trace recording using Branch Trace Store (BTS) format.
380 Evaluate expression by using the compiler and print result.
384 Explicit commands for enabling and disabling tui mode.
387 set mpx bound on i386 and amd64
388 Support for bound table investigation on Intel MPX enabled applications.
392 Start branch trace recording using Intel Processor Trace format.
395 Print information about branch tracing internals.
397 maint btrace packet-history
398 Print the raw branch tracing data.
400 maint btrace clear-packet-history
401 Discard the stored raw branch tracing data.
404 Discard all branch tracing data. It will be fetched and processed
405 anew by the next "record" command.
410 Renamed from "set debug dwarf2-die".
412 Renamed from "show debug dwarf2-die".
415 Renamed from "set debug dwarf2-read".
416 show debug dwarf-read
417 Renamed from "show debug dwarf2-read".
419 maint set dwarf always-disassemble
420 Renamed from "maint set dwarf2 always-disassemble".
421 maint show dwarf always-disassemble
422 Renamed from "maint show dwarf2 always-disassemble".
424 maint set dwarf max-cache-age
425 Renamed from "maint set dwarf2 max-cache-age".
426 maint show dwarf max-cache-age
427 Renamed from "maint show dwarf2 max-cache-age".
430 show debug dwarf-line
431 Control display of debugging info regarding DWARF line processing.
435 Set the maximum number of candidates to be considered during
436 completion. The default value is 200. This limit allows GDB
437 to avoid generating large completion lists, the computation of
438 which can cause the debugger to become temporarily unresponsive.
440 set history remove-duplicates
441 show history remove-duplicates
442 Control the removal of duplicate history entries.
444 maint set symbol-cache-size
445 maint show symbol-cache-size
446 Control the size of the symbol cache.
448 set|show record btrace bts buffer-size
449 Set and show the size of the ring buffer used for branch tracing in
451 The obtained size may differ from the requested size. Use "info
452 record" to see the obtained buffer size.
454 set debug linux-namespaces
455 show debug linux-namespaces
456 Control display of debugging info regarding Linux namespaces.
458 set|show record btrace pt buffer-size
459 Set and show the size of the ring buffer used for branch tracing in
460 Intel Processor Trace format.
461 The obtained size may differ from the requested size. Use "info
462 record" to see the obtained buffer size.
464 maint set|show btrace pt skip-pad
465 Set and show whether PAD packets are skipped when computing the
468 * The command 'thread apply all' can now support new option '-ascending'
469 to call its specified command for all threads in ascending order.
471 * Python/Guile scripting
473 ** GDB now supports auto-loading of Python/Guile scripts contained in the
474 special section named `.debug_gdb_scripts'.
478 qXfer:btrace-conf:read
479 Return the branch trace configuration for the current thread.
481 Qbtrace-conf:bts:size
482 Set the requested ring buffer size for branch tracing in BTS format.
485 Enable Intel Procesor Trace-based branch tracing for the current
486 process. The remote stub reports support for this packet to GDB's
490 Set the requested ring buffer size for branch tracing in Intel Processor
494 Indicates a memory breakpoint instruction was executed, irrespective
495 of whether it was GDB that planted the breakpoint or the breakpoint
496 is hardcoded in the program. This is required for correct non-stop
500 Indicates the target stopped for a hardware breakpoint. This is
501 required for correct non-stop mode operation.
504 Return information about files on the remote system.
507 Return the full absolute name of the file that was executed to
508 create a process running on the remote system.
511 Select the filesystem on which vFile: operations with filename
512 arguments will operate. This is required for GDB to be able to
513 access files on remote targets where the remote stub does not
514 share a common filesystem with the inferior(s).
517 Indicates that a fork system call was executed.
520 Indicates that a vfork system call was executed.
522 vforkdone stop reason
523 Indicates that a vfork child of the specified process has executed
524 an exec or exit, allowing the vfork parent to resume execution.
526 fork-events and vfork-events features in qSupported
527 The qSupported packet allows GDB to request support for fork and
528 vfork events using new 'gdbfeatures' fork-events and vfork-events,
529 and the qSupported response can contain the corresponding
530 'stubfeatures'. Set and show commands can be used to display
531 whether these features are enabled.
533 * Extended-remote fork events
535 ** GDB now has support for fork events on extended-remote Linux
536 targets. For targets with Linux kernels 2.5.60 and later, this
537 enables follow-fork-mode and detach-on-fork for both fork and
538 vfork, as well as fork and vfork catchpoints.
540 * The info record command now shows the recording format and the
541 branch tracing configuration for the current thread when using
542 the btrace record target.
543 For the BTS format, it shows the ring buffer size.
545 * GDB now has support for DTrace USDT (Userland Static Defined
546 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
548 * GDB now supports access to vector registers on S/390 GNU/Linux
551 * Removed command line options
553 -xdb HP-UX XDB compatibility mode.
555 * Removed targets and native configurations
557 HP/PA running HP-UX hppa*-*-hpux*
558 Itanium running HP-UX ia64-*-hpux*
560 * New configure options
563 This configure option allows the user to build GDB with support for
564 Intel Processor Trace (default: auto). This requires libipt.
566 --with-libipt-prefix=PATH
567 Specify the path to the version of libipt that GDB should use.
568 $PATH/include should contain the intel-pt.h header and
569 $PATH/lib should contain the libipt.so library.
571 *** Changes in GDB 7.9.1
575 ** Xmethods can now specify a result type.
577 *** Changes in GDB 7.9
579 * GDB now supports hardware watchpoints on x86 GNU Hurd.
583 ** You can now access frame registers from Python scripts.
584 ** New attribute 'producer' for gdb.Symtab objects.
585 ** gdb.Objfile objects have a new attribute "progspace",
586 which is the gdb.Progspace object of the containing program space.
587 ** gdb.Objfile objects have a new attribute "owner".
588 ** gdb.Objfile objects have a new attribute "build_id",
589 which is the build ID generated when the file was built.
590 ** gdb.Objfile objects have a new method "add_separate_debug_file".
591 ** A new event "gdb.clear_objfiles" has been added, triggered when
592 selecting a new file to debug.
593 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
594 ** New function gdb.lookup_objfile.
596 New events which are triggered when GDB modifies the state of the
599 ** gdb.events.inferior_call_pre: Function call is about to be made.
600 ** gdb.events.inferior_call_post: Function call has just been made.
601 ** gdb.events.memory_changed: A memory location has been altered.
602 ** gdb.events.register_changed: A register has been altered.
604 * New Python-based convenience functions:
606 ** $_caller_is(name [, number_of_frames])
607 ** $_caller_matches(regexp [, number_of_frames])
608 ** $_any_caller_is(name [, number_of_frames])
609 ** $_any_caller_matches(regexp [, number_of_frames])
611 * GDB now supports the compilation and injection of source code into
612 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
613 to compile the source code to object code, and if successful, inject
614 and execute that code within the current context of the inferior.
615 Currently the C language is supported. The commands used to
616 interface with this new feature are:
618 compile code [-raw|-r] [--] [source code]
619 compile file [-raw|-r] filename
623 demangle [-l language] [--] name
624 Demangle "name" in the specified language, or the current language
625 if elided. This command is renamed from the "maint demangle" command.
626 The latter is kept as a no-op to avoid "maint demangle" being interpreted
627 as "maint demangler-warning".
629 queue-signal signal-name-or-number
630 Queue a signal to be delivered to the thread when it is resumed.
632 add-auto-load-scripts-directory directory
633 Add entries to the list of directories from which to load auto-loaded
636 maint print user-registers
637 List all currently available "user" registers.
639 compile code [-r|-raw] [--] [source code]
640 Compile, inject, and execute in the inferior the executable object
641 code produced by compiling the provided source code.
643 compile file [-r|-raw] filename
644 Compile and inject into the inferior the executable object code
645 produced by compiling the source code stored in the filename
648 * On resume, GDB now always passes the signal the program had stopped
649 for to the thread the signal was sent to, even if the user changed
650 threads before resuming. Previously GDB would often (but not
651 always) deliver the signal to the thread that happens to be current
654 * Conversely, the "signal" command now consistently delivers the
655 requested signal to the current thread. GDB now asks for
656 confirmation if the program had stopped for a signal and the user
657 switched threads meanwhile.
659 * "breakpoint always-inserted" modes "off" and "auto" merged.
661 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
662 won't remove breakpoints from the target until all threads stop,
663 even in non-stop mode. The "auto" mode has been removed, and "off"
664 is now the default mode.
668 set debug symbol-lookup
669 show debug symbol-lookup
670 Control display of debugging info regarding symbol lookup.
674 ** The -list-thread-groups command outputs an exit-code field for
675 inferiors that have exited.
679 MIPS SDE mips*-sde*-elf*
683 Support for these obsolete configurations has been removed.
685 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
686 SGI Irix-5.x mips-*-irix5*
687 SGI Irix-6.x mips-*-irix6*
688 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
689 VAX running Ultrix vax-*-ultrix*
691 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
692 and "assf"), have been removed. Use the "sharedlibrary" command, or
693 its alias "share", instead.
695 *** Changes in GDB 7.8
697 * New command line options
700 This is an alias for the --data-directory option.
702 * GDB supports printing and modifying of variable length automatic arrays
703 as specified in ISO C99.
705 * The ARM simulator now supports instruction level tracing
706 with or without disassembly.
710 GDB now has support for scripting using Guile. Whether this is
711 available is determined at configure time.
712 Guile version 2.0 or greater is required.
713 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
715 * New commands (for set/show, see "New options" below)
719 Invoke CODE by passing it to the Guile interpreter.
723 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
725 info auto-load guile-scripts [regexp]
726 Print the list of automatically loaded Guile scripts.
728 * The source command is now capable of sourcing Guile scripts.
729 This feature is dependent on the debugger being built with Guile support.
733 set print symbol-loading (off|brief|full)
734 show print symbol-loading
735 Control whether to print informational messages when loading symbol
736 information for a file. The default is "full", but when debugging
737 programs with large numbers of shared libraries the amount of output
740 set guile print-stack (none|message|full)
741 show guile print-stack
742 Show a stack trace when an error is encountered in a Guile script.
744 set auto-load guile-scripts (on|off)
745 show auto-load guile-scripts
746 Control auto-loading of Guile script files.
748 maint ada set ignore-descriptive-types (on|off)
749 maint ada show ignore-descriptive-types
750 Control whether the debugger should ignore descriptive types in Ada
751 programs. The default is not to ignore the descriptive types. See
752 the user manual for more details on descriptive types and the intended
753 usage of this option.
755 set auto-connect-native-target
757 Control whether GDB is allowed to automatically connect to the
758 native target for the run, attach, etc. commands when not connected
759 to any target yet. See also "target native" below.
761 set record btrace replay-memory-access (read-only|read-write)
762 show record btrace replay-memory-access
763 Control what memory accesses are allowed during replay.
765 maint set target-async (on|off)
766 maint show target-async
767 This controls whether GDB targets operate in synchronous or
768 asynchronous mode. Normally the default is asynchronous, if it is
769 available; but this can be changed to more easily debug problems
770 occurring only in synchronous mode.
772 set mi-async (on|off)
774 Control whether MI asynchronous mode is preferred. This supersedes
775 "set target-async" of previous GDB versions.
777 * "set target-async" is deprecated as a CLI option and is now an alias
778 for "set mi-async" (only puts MI into async mode).
780 * Background execution commands (e.g., "c&", "s&", etc.) are now
781 possible ``out of the box'' if the target supports them. Previously
782 the user would need to explicitly enable the possibility with the
783 "set target-async on" command.
785 * New features in the GDB remote stub, GDBserver
787 ** New option --debug-format=option1[,option2,...] allows one to add
788 additional text to each output. At present only timestamps
789 are supported: --debug-format=timestamps.
790 Timestamps can also be turned on with the
791 "monitor set debug-format timestamps" command from GDB.
793 * The 'record instruction-history' command now starts counting instructions
794 at one. This also affects the instruction ranges reported by the
795 'record function-call-history' command when given the /i modifier.
797 * The command 'record function-call-history' supports a new modifier '/c' to
798 indent the function names based on their call stack depth.
799 The fields for the '/i' and '/l' modifier have been reordered.
800 The source line range is now prefixed with 'at'.
801 The instruction range is now prefixed with 'inst'.
802 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
803 "record instruction-history" and "list" commands.
805 * The ranges given as arguments to the 'record function-call-history' and
806 'record instruction-history' commands are now inclusive.
808 * The btrace record target now supports the 'record goto' command.
809 For locations inside the execution trace, the back trace is computed
810 based on the information stored in the execution trace.
812 * The btrace record target supports limited reverse execution and replay.
813 The target does not record data and therefore does not allow reading
816 * The "catch syscall" command now works on s390*-linux* targets.
818 * The "compare-sections" command is no longer specific to target
819 remote. It now works with all targets.
821 * All native targets are now consistently called "native".
822 Consequently, the "target child", "target GNU", "target djgpp",
823 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
824 commands have been replaced with "target native". The QNX/NTO port
825 leaves the "procfs" target in place and adds a "native" target for
826 consistency with other ports. The impact on users should be minimal
827 as these commands previously either throwed an error, or were
828 no-ops. The target's name is visible in the output of the following
829 commands: "help target", "info target", "info files", "maint print
832 * The "target native" command now connects to the native target. This
833 can be used to launch native programs even when "set
834 auto-connect-native-target" is set to off.
836 * GDB now supports access to Intel MPX registers on GNU/Linux.
838 * Support for Intel AVX-512 registers on GNU/Linux.
839 Support displaying and modifying Intel AVX-512 registers
840 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
844 qXfer:btrace:read's annex
845 The qXfer:btrace:read packet supports a new annex 'delta' to read
846 branch trace incrementally.
850 ** Valid Python operations on gdb.Value objects representing
851 structs/classes invoke the corresponding overloaded operators if
853 ** New `Xmethods' feature in the Python API. Xmethods are
854 additional methods or replacements for existing methods of a C++
855 class. This feature is useful for those cases where a method
856 defined in C++ source code could be inlined or optimized out by
857 the compiler, making it unavailable to GDB.
860 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
862 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
863 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
864 its alias "share", instead.
866 * The commands "set remotebaud" and "show remotebaud" are no longer
867 supported. Use "set serial baud" and "show serial baud" (respectively)
872 ** A new option "-gdb-set mi-async" replaces "-gdb-set
873 target-async". The latter is left as a deprecated alias of the
874 former for backward compatibility. If the target supports it,
875 CLI background execution commands are now always possible by
876 default, independently of whether the frontend stated a
877 preference for asynchronous execution with "-gdb-set mi-async".
878 Previously "-gdb-set target-async off" affected both MI execution
879 commands and CLI execution commands.
881 *** Changes in GDB 7.7
883 * Improved support for process record-replay and reverse debugging on
884 arm*-linux* targets. Support for thumb32 and syscall instruction
885 recording has been added.
887 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
889 * GDB now supports Fission DWP file format version 2.
890 http://gcc.gnu.org/wiki/DebugFission
892 * New convenience function "$_isvoid", to check whether an expression
893 is void. A void expression is an expression where the type of the
894 result is "void". For example, some convenience variables may be
895 "void" when evaluated (e.g., "$_exitcode" before the execution of
896 the program being debugged; or an undefined convenience variable).
897 Another example, when calling a function whose return type is
900 * The "maintenance print objfiles" command now takes an optional regexp.
902 * The "catch syscall" command now works on arm*-linux* targets.
904 * GDB now consistently shows "<not saved>" when printing values of
905 registers the debug info indicates have not been saved in the frame
906 and there's nowhere to retrieve them from
907 (callee-saved/call-clobbered registers):
912 (gdb) info registers rax
915 Before, the former would print "<optimized out>", and the latter
916 "*value not available*".
918 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
923 ** Frame filters and frame decorators have been added.
924 ** Temporary breakpoints are now supported.
925 ** Line tables representation has been added.
926 ** New attribute 'parent_type' for gdb.Field objects.
927 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
928 ** New attribute 'name' for gdb.Type objects.
932 Nios II ELF nios2*-*-elf
933 Nios II GNU/Linux nios2*-*-linux
934 Texas Instruments MSP430 msp430*-*-elf
936 * Removed native configurations
938 Support for these a.out NetBSD and OpenBSD obsolete configurations has
939 been removed. ELF variants of these configurations are kept supported.
941 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
942 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
943 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
944 i[34567]86-*-openbsd3.[0-3]
945 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
946 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
947 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
951 Like "catch throw", but catches a re-thrown exception.
953 Renamed from old "maint check-symtabs".
955 Perform consistency checks on symtabs.
957 Expand symtabs matching an optional regexp.
960 Display the details of GDB configure-time options.
962 maint set|show per-command
963 maint set|show per-command space
964 maint set|show per-command time
965 maint set|show per-command symtab
966 Enable display of per-command gdb resource usage.
968 remove-symbol-file FILENAME
969 remove-symbol-file -a ADDRESS
970 Remove a symbol file added via add-symbol-file. The file to remove
971 can be identified by its filename or by an address that lies within
972 the boundaries of this symbol file in memory.
975 info exceptions REGEXP
976 Display the list of Ada exceptions defined in the program being
977 debugged. If provided, only the exceptions whose names match REGEXP
982 set debug symfile off|on
984 Control display of debugging info regarding reading symbol files and
985 symbol tables within those files
987 set print raw frame-arguments
988 show print raw frame-arguments
989 Set/show whether to print frame arguments in raw mode,
990 disregarding any defined pretty-printers.
992 set remote trace-status-packet
993 show remote trace-status-packet
994 Set/show the use of remote protocol qTStatus packet.
998 Control display of debugging messages related to Nios II targets.
1002 Control whether target-assisted range stepping is enabled.
1004 set startup-with-shell
1005 show startup-with-shell
1006 Specifies whether Unix child processes are started via a shell or
1011 Use the target memory cache for accesses to the code segment. This
1012 improves performance of remote debugging (particularly disassembly).
1014 * You can now use a literal value 'unlimited' for options that
1015 interpret 0 or -1 as meaning "unlimited". E.g., "set
1016 trace-buffer-size unlimited" is now an alias for "set
1017 trace-buffer-size -1" and "set height unlimited" is now an alias for
1020 * The "set debug symtab-create" debugging option of GDB has been changed to
1021 accept a verbosity level. 0 means "off", 1 provides basic debugging
1022 output, and values of 2 or greater provides more verbose output.
1024 * New command-line options
1026 Display the details of GDB configure-time options.
1028 * The command 'tsave' can now support new option '-ctf' to save trace
1029 buffer in Common Trace Format.
1031 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1034 * GDB now implements the the C++ 'typeid' operator.
1036 * The new convenience variable $_exception holds the exception being
1037 thrown or caught at an exception-related catchpoint.
1039 * The exception-related catchpoints, like "catch throw", now accept a
1040 regular expression which can be used to filter exceptions by type.
1042 * The new convenience variable $_exitsignal is automatically set to
1043 the terminating signal number when the program being debugged dies
1044 due to an uncaught signal.
1048 ** All MI commands now accept an optional "--language" option.
1049 Support for this feature can be verified by using the "-list-features"
1050 command, which should contain "language-option".
1052 ** The new command -info-gdb-mi-command allows the user to determine
1053 whether a GDB/MI command is supported or not.
1055 ** The "^error" result record returned when trying to execute an undefined
1056 GDB/MI command now provides a variable named "code" whose content is the
1057 "undefined-command" error code. Support for this feature can be verified
1058 by using the "-list-features" command, which should contain
1059 "undefined-command-error-code".
1061 ** The -trace-save MI command can optionally save trace buffer in Common
1064 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1066 ** The command -data-list-register-values now accepts an optional
1067 "--skip-unavailable" option. When used, only the available registers
1070 ** The new command -trace-frame-collected dumps collected variables,
1071 computed expressions, tvars, memory and registers in a traceframe.
1073 ** The commands -stack-list-locals, -stack-list-arguments and
1074 -stack-list-variables now accept an option "--skip-unavailable".
1075 When used, only the available locals or arguments are displayed.
1077 ** The -exec-run command now accepts an optional "--start" option.
1078 When used, the command follows the same semantics as the "start"
1079 command, stopping the program's execution at the start of its
1080 main subprogram. Support for this feature can be verified using
1081 the "-list-features" command, which should contain
1082 "exec-run-start-option".
1084 ** The new commands -catch-assert and -catch-exceptions insert
1085 catchpoints stopping the program when Ada exceptions are raised.
1087 ** The new command -info-ada-exceptions provides the equivalent of
1088 the new "info exceptions" command.
1090 * New system-wide configuration scripts
1091 A GDB installation now provides scripts suitable for use as system-wide
1092 configuration scripts for the following systems:
1096 * GDB now supports target-assigned range stepping with remote targets.
1097 This improves the performance of stepping source lines by reducing
1098 the number of control packets from/to GDB. See "New remote packets"
1101 * GDB now understands the element 'tvar' in the XML traceframe info.
1102 It has the id of the collected trace state variables.
1104 * On S/390 targets that provide the transactional-execution feature,
1105 the program interruption transaction diagnostic block (TDB) is now
1106 represented as a number of additional "registers" in GDB.
1108 * New remote packets
1112 The vCont packet supports a new 'r' action, that tells the remote
1113 stub to step through an address range itself, without GDB
1114 involvemement at each single-step.
1116 qXfer:libraries-svr4:read's annex
1117 The previously unused annex of the qXfer:libraries-svr4:read packet
1118 is now used to support passing an argument list. The remote stub
1119 reports support for this argument list to GDB's qSupported query.
1120 The defined arguments are "start" and "prev", used to reduce work
1121 necessary for library list updating, resulting in significant
1124 * New features in the GDB remote stub, GDBserver
1126 ** GDBserver now supports target-assisted range stepping. Currently
1127 enabled on x86/x86_64 GNU/Linux targets.
1129 ** GDBserver now adds element 'tvar' in the XML in the reply to
1130 'qXfer:traceframe-info:read'. It has the id of the collected
1131 trace state variables.
1133 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1136 * New 'z' formatter for printing and examining memory, this displays the
1137 value as hexadecimal zero padded on the left to the size of the type.
1139 * GDB can now use Windows x64 unwinding data.
1141 * The "set remotebaud" command has been replaced by "set serial baud".
1142 Similarly, "show remotebaud" has been replaced by "show serial baud".
1143 The "set remotebaud" and "show remotebaud" commands are still available
1144 to provide backward compatibility with older versions of GDB.
1146 *** Changes in GDB 7.6
1148 * Target record has been renamed to record-full.
1149 Record/replay is now enabled with the "record full" command.
1150 This also affects settings that are associated with full record/replay
1151 that have been moved from "set/show record" to "set/show record full":
1153 set|show record full insn-number-max
1154 set|show record full stop-at-limit
1155 set|show record full memory-query
1157 * A new record target "record-btrace" has been added. The new target
1158 uses hardware support to record the control-flow of a process. It
1159 does not support replaying the execution, but it implements the
1160 below new commands for investigating the recorded execution log.
1161 This new recording method can be enabled using:
1165 The "record-btrace" target is only available on Intel Atom processors
1166 and requires a Linux kernel 2.6.32 or later.
1168 * Two new commands have been added for record/replay to give information
1169 about the recorded execution without having to replay the execution.
1170 The commands are only supported by "record btrace".
1172 record instruction-history prints the execution history at
1173 instruction granularity
1175 record function-call-history prints the execution history at
1176 function granularity
1178 * New native configurations
1180 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1181 FreeBSD/powerpc powerpc*-*-freebsd
1182 x86_64/Cygwin x86_64-*-cygwin*
1183 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1187 ARM AArch64 aarch64*-*-elf
1188 ARM AArch64 GNU/Linux aarch64*-*-linux
1189 Lynx 178 PowerPC powerpc-*-lynx*178
1190 x86_64/Cygwin x86_64-*-cygwin*
1191 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1193 * If the configured location of system.gdbinit file (as given by the
1194 --with-system-gdbinit option at configure time) is in the
1195 data-directory (as specified by --with-gdb-datadir at configure
1196 time) or in one of its subdirectories, then GDB will look for the
1197 system-wide init file in the directory specified by the
1198 --data-directory command-line option.
1200 * New command line options:
1202 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1203 other initialization files, unlike -nx which disables all of them.
1205 * Removed command line options
1207 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1210 * The 'ptype' and 'whatis' commands now accept an argument to control
1213 * 'info proc' now works on some core files.
1217 ** Vectors can be created with gdb.Type.vector.
1219 ** Python's atexit.register now works in GDB.
1221 ** Types can be pretty-printed via a Python API.
1223 ** Python 3 is now supported (in addition to Python 2.4 or later)
1225 ** New class gdb.Architecture exposes GDB's internal representation
1226 of architecture in the Python API.
1228 ** New method Frame.architecture returns the gdb.Architecture object
1229 corresponding to the frame's architecture.
1231 * New Python-based convenience functions:
1233 ** $_memeq(buf1, buf2, length)
1234 ** $_streq(str1, str2)
1236 ** $_regex(str, regex)
1238 * The 'cd' command now defaults to using '~' (the home directory) if not
1241 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1242 default for GCC since November 2000.
1244 * The command 'forward-search' can now be abbreviated as 'fo'.
1246 * The command 'info tracepoints' can now display 'installed on target'
1247 or 'not installed on target' for each non-pending location of tracepoint.
1249 * New configure options
1251 --enable-libmcheck/--disable-libmcheck
1252 By default, development versions are built with -lmcheck on hosts
1253 that support it, in order to help track memory corruption issues.
1254 Release versions, on the other hand, are built without -lmcheck
1255 by default. The --enable-libmcheck/--disable-libmcheck configure
1256 options allow the user to override that default.
1257 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1258 This configure option allows the user to build GDB with
1259 libbabeltrace using which GDB can read Common Trace Format data.
1261 * New commands (for set/show, see "New options" below)
1264 Catch signals. This is similar to "handle", but allows commands and
1265 conditions to be attached.
1268 List the BFDs known to GDB.
1270 python-interactive [command]
1272 Start a Python interactive prompt, or evaluate the optional command
1273 and print the result of expressions.
1276 "py" is a new alias for "python".
1278 enable type-printer [name]...
1279 disable type-printer [name]...
1280 Enable or disable type printers.
1284 ** For the Renesas Super-H architecture, the "regs" command has been removed
1285 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1290 set print type methods (on|off)
1291 show print type methods
1292 Control whether method declarations are displayed by "ptype".
1293 The default is to show them.
1295 set print type typedefs (on|off)
1296 show print type typedefs
1297 Control whether typedef definitions are displayed by "ptype".
1298 The default is to show them.
1300 set filename-display basename|relative|absolute
1301 show filename-display
1302 Control the way in which filenames is displayed.
1303 The default is "relative", which preserves previous behavior.
1305 set trace-buffer-size
1306 show trace-buffer-size
1307 Request target to change the size of trace buffer.
1309 set remote trace-buffer-size-packet auto|on|off
1310 show remote trace-buffer-size-packet
1311 Control the use of the remote protocol `QTBuffer:size' packet.
1315 Control display of debugging messages related to ARM AArch64.
1318 set debug coff-pe-read
1319 show debug coff-pe-read
1320 Control display of debugging messages related to reading of COFF/PE
1325 Control display of debugging messages related to Mach-O symbols
1328 set debug notification
1329 show debug notification
1330 Control display of debugging info for async remote notification.
1334 ** Command parameter changes are now notified using new async record
1335 "=cmd-param-changed".
1336 ** Trace frame changes caused by command "tfind" are now notified using
1337 new async record "=traceframe-changed".
1338 ** The creation, deletion and modification of trace state variables
1339 are now notified using new async records "=tsv-created",
1340 "=tsv-deleted" and "=tsv-modified".
1341 ** The start and stop of process record are now notified using new
1342 async record "=record-started" and "=record-stopped".
1343 ** Memory changes are now notified using new async record
1345 ** The data-disassemble command response will include a "fullname" field
1346 containing the absolute file name when source has been requested.
1347 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1348 command, to allow pattern filling of memory areas.
1349 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1350 library load/unload events.
1351 ** The response to breakpoint commands and breakpoint async records
1352 includes an "installed" field containing a boolean state about each
1353 non-pending tracepoint location is whether installed on target or not.
1354 ** Output of the "-trace-status" command includes a "trace-file" field
1355 containing the name of the trace file being examined. This field is
1356 optional, and only present when examining a trace file.
1357 ** The "fullname" field is now always present along with the "file" field,
1358 even if the file cannot be found by GDB.
1360 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1361 You must have the LZMA library available when configuring GDB for this
1362 feature to be enabled. For more information, see:
1363 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1365 * New remote packets
1368 Set the size of trace buffer. The remote stub reports support for this
1369 packet to gdb's qSupported query.
1372 Enable Branch Trace Store (BTS)-based branch tracing for the current
1373 thread. The remote stub reports support for this packet to gdb's
1377 Disable branch tracing for the current thread. The remote stub reports
1378 support for this packet to gdb's qSupported query.
1381 Read the traced branches for the current thread. The remote stub
1382 reports support for this packet to gdb's qSupported query.
1384 *** Changes in GDB 7.5
1386 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1387 for more x32 ABI info.
1389 * GDB now supports access to MIPS DSP registers on Linux targets.
1391 * GDB now supports debugging microMIPS binaries.
1393 * The "info os" command on GNU/Linux can now display information on
1394 several new classes of objects managed by the operating system:
1395 "info os procgroups" lists process groups
1396 "info os files" lists file descriptors
1397 "info os sockets" lists internet-domain sockets
1398 "info os shm" lists shared-memory regions
1399 "info os semaphores" lists semaphores
1400 "info os msg" lists message queues
1401 "info os modules" lists loaded kernel modules
1403 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1404 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1405 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1406 options and inspect the probe arguments using the new $_probe_arg family
1407 of convenience variables. You can obtain more information about SystemTap
1408 in <http://sourceware.org/systemtap/>.
1410 * GDB now supports reversible debugging on ARM, it allows you to
1411 debug basic ARM and THUMB instructions, and provides
1412 record/replay support.
1414 * The option "symbol-reloading" has been deleted as it is no longer used.
1418 ** GDB commands implemented in Python can now be put in command class
1421 ** The "maint set python print-stack on|off" is now deleted.
1423 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1424 apply "flag enum"-style pretty-printing to any enum.
1426 ** gdb.lookup_symbol can now work when there is no current frame.
1428 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1429 the source at which the symbol was defined.
1431 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1432 method 'value'. The former indicates whether the symbol needs a
1433 frame in order to compute its value, and the latter computes the
1436 ** A new method 'referenced_value' on gdb.Value objects which can
1437 dereference pointer as well as C++ reference values.
1439 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1440 which return the global and static blocks (as gdb.Block objects),
1441 of the underlying symbol table, respectively.
1443 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1444 object associated with a PC value.
1446 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1447 of the address range occupied by code for the current source line.
1449 * Go language support.
1450 GDB now supports debugging programs written in the Go programming
1453 * GDBserver now supports stdio connections.
1454 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1456 * The binary "gdbtui" can no longer be built or installed.
1457 Use "gdb -tui" instead.
1459 * GDB will now print "flag" enums specially. A flag enum is one where
1460 all the enumerator values have no bits in common when pairwise
1461 "and"ed. When printing a value whose type is a flag enum, GDB will
1462 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1463 (gdb) print (enum E) 3
1466 * The filename part of a linespec will now match trailing components
1467 of a source file name. For example, "break gcc/expr.c:1000" will
1468 now set a breakpoint in build/gcc/expr.c, but not
1469 build/libcpp/expr.c.
1471 * The "info proc" and "generate-core-file" commands will now also
1472 work on remote targets connected to GDBserver on Linux.
1474 * The command "info catch" has been removed. It has been disabled
1475 since December 2007.
1477 * The "catch exception" and "catch assert" commands now accept
1478 a condition at the end of the command, much like the "break"
1479 command does. For instance:
1481 (gdb) catch exception Constraint_Error if Barrier = True
1483 Previously, it was possible to add a condition to such catchpoints,
1484 but it had to be done as a second step, after the catchpoint had been
1485 created, using the "condition" command.
1487 * The "info static-tracepoint-marker" command will now also work on
1488 native Linux targets with in-process agent.
1490 * GDB can now set breakpoints on inlined functions.
1492 * The .gdb_index section has been updated to include symbols for
1493 inlined functions. GDB will ignore older .gdb_index sections by
1494 default, which could cause symbol files to be loaded more slowly
1495 until their .gdb_index sections can be recreated. The new command
1496 "set use-deprecated-index-sections on" will cause GDB to use any older
1497 .gdb_index sections it finds. This will restore performance, but the
1498 ability to set breakpoints on inlined functions will be lost in symbol
1499 files with older .gdb_index sections.
1501 The .gdb_index section has also been updated to record more information
1502 about each symbol. This speeds up the "info variables", "info functions"
1503 and "info types" commands when used with programs having the .gdb_index
1504 section, as well as speeding up debugging with shared libraries using
1505 the .gdb_index section.
1507 * Ada support for GDB/MI Variable Objects has been added.
1509 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1514 ** New command -info-os is the MI equivalent of "info os".
1516 ** Output logs ("set logging" and related) now include MI output.
1520 ** "set use-deprecated-index-sections on|off"
1521 "show use-deprecated-index-sections on|off"
1522 Controls the use of deprecated .gdb_index sections.
1524 ** "catch load" and "catch unload" can be used to stop when a shared
1525 library is loaded or unloaded, respectively.
1527 ** "enable count" can be used to auto-disable a breakpoint after
1530 ** "info vtbl" can be used to show the virtual method tables for
1531 C++ and Java objects.
1533 ** "explore" and its sub commands "explore value" and "explore type"
1534 can be used to recursively explore values and types of
1535 expressions. These commands are available only if GDB is
1536 configured with '--with-python'.
1538 ** "info auto-load" shows status of all kinds of auto-loaded files,
1539 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1540 sequences of commands files, "info auto-load python-scripts"
1541 shows status of auto-loading Python script files,
1542 "info auto-load local-gdbinit" shows status of loading init file
1543 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1544 status of inferior specific thread debugging shared library loading.
1546 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1547 and "show auto-load-scripts" commands have been deprecated, use their
1548 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1549 and "show auto-load python-scripts" counterparts instead.
1551 ** "dprintf location,format,args..." creates a dynamic printf, which
1552 is basically a breakpoint that does a printf and immediately
1553 resumes your program's execution, so it is like a printf that you
1554 can insert dynamically at runtime instead of at compiletime.
1556 ** "set print symbol"
1558 Controls whether GDB attempts to display the symbol, if any,
1559 corresponding to addresses it prints. This defaults to "on", but
1560 you can set it to "off" to restore GDB's previous behavior.
1562 * Deprecated commands
1564 ** For the Renesas Super-H architecture, the "regs" command has been
1565 deprecated, and "info all-registers" should be used instead.
1569 Renesas RL78 rl78-*-elf
1570 HP OpenVMS ia64 ia64-hp-openvms*
1572 * GDBserver supports evaluation of breakpoint conditions. When
1573 support is advertised by GDBserver, GDB may be told to send the
1574 breakpoint conditions in bytecode form to GDBserver. GDBserver
1575 will only report the breakpoint trigger to GDB when its condition
1580 set mips compression
1581 show mips compression
1582 Select the compressed ISA encoding used in functions that have no symbol
1583 information available. The encoding can be set to either of:
1586 and is updated automatically from ELF file flags if available.
1588 set breakpoint condition-evaluation
1589 show breakpoint condition-evaluation
1590 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1591 GDBserver ("target"). Default option "auto" chooses the most efficient
1593 This option can improve debugger efficiency depending on the speed of the
1597 Disable auto-loading globally.
1600 Show auto-loading setting of all kinds of auto-loaded files.
1602 set auto-load gdb-scripts on|off
1603 show auto-load gdb-scripts
1604 Control auto-loading of GDB canned sequences of commands files.
1606 set auto-load python-scripts on|off
1607 show auto-load python-scripts
1608 Control auto-loading of Python script files.
1610 set auto-load local-gdbinit on|off
1611 show auto-load local-gdbinit
1612 Control loading of init file (.gdbinit) from current directory.
1614 set auto-load libthread-db on|off
1615 show auto-load libthread-db
1616 Control auto-loading of inferior specific thread debugging shared library.
1618 set auto-load scripts-directory <dir1>[:<dir2>...]
1619 show auto-load scripts-directory
1620 Set a list of directories from which to load auto-loaded scripts.
1621 Automatically loaded Python scripts and GDB scripts are located in one
1622 of the directories listed by this option.
1623 The delimiter (':' above) may differ according to the host platform.
1625 set auto-load safe-path <dir1>[:<dir2>...]
1626 show auto-load safe-path
1627 Set a list of directories from which it is safe to auto-load files.
1628 The delimiter (':' above) may differ according to the host platform.
1630 set debug auto-load on|off
1631 show debug auto-load
1632 Control display of debugging info for auto-loading the files above.
1634 set dprintf-style gdb|call|agent
1636 Control the way in which a dynamic printf is performed; "gdb"
1637 requests a GDB printf command, while "call" causes dprintf to call a
1638 function in the inferior. "agent" requests that the target agent
1639 (such as GDBserver) do the printing.
1641 set dprintf-function <expr>
1642 show dprintf-function
1643 set dprintf-channel <expr>
1644 show dprintf-channel
1645 Set the function and optional first argument to the call when using
1646 the "call" style of dynamic printf.
1648 set disconnected-dprintf on|off
1649 show disconnected-dprintf
1650 Control whether agent-style dynamic printfs continue to be in effect
1651 after GDB disconnects.
1653 * New configure options
1655 --with-auto-load-dir
1656 Configure default value for the 'set auto-load scripts-directory'
1657 setting above. It defaults to '$debugdir:$datadir/auto-load',
1658 $debugdir representing global debugging info directories (available
1659 via 'show debug-file-directory') and $datadir representing GDB's data
1660 directory (available via 'show data-directory').
1662 --with-auto-load-safe-path
1663 Configure default value for the 'set auto-load safe-path' setting
1664 above. It defaults to the --with-auto-load-dir setting.
1666 --without-auto-load-safe-path
1667 Set 'set auto-load safe-path' to '/', effectively disabling this
1670 * New remote packets
1672 z0/z1 conditional breakpoints extension
1674 The z0/z1 breakpoint insertion packets have been extended to carry
1675 a list of conditional expressions over to the remote stub depending on the
1676 condition evaluation mode. The use of this extension can be controlled
1677 via the "set remote conditional-breakpoints-packet" command.
1681 Specify the signals which the remote stub may pass to the debugged
1682 program without GDB involvement.
1684 * New command line options
1686 --init-command=FILE, -ix Like --command, -x but execute it
1687 before loading inferior.
1688 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1689 execute it before loading inferior.
1691 *** Changes in GDB 7.4
1693 * GDB now handles ambiguous linespecs more consistently; the existing
1694 FILE:LINE support has been expanded to other types of linespecs. A
1695 breakpoint will now be set on all matching locations in all
1696 inferiors, and locations will be added or removed according to
1699 * GDB now allows you to skip uninteresting functions and files when
1700 stepping with the "skip function" and "skip file" commands.
1702 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1703 and "show remote hardware-watchpoint-length-limit". These allows to
1704 set or show the maximum length limit (in bytes) of a remote
1705 target hardware watchpoint.
1707 This allows e.g. to use "unlimited" hardware watchpoints with the
1708 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1709 watchpoints are slower than real hardware watchpoints but are
1710 significantly faster than gdb software watchpoints.
1714 ** The register_pretty_printer function in module gdb.printing now takes
1715 an optional `replace' argument. If True, the new printer replaces any
1718 ** The "maint set python print-stack on|off" command has been
1719 deprecated and will be deleted in GDB 7.5.
1720 A new command: "set python print-stack none|full|message" has
1721 replaced it. Additionally, the default for "print-stack" is
1722 now "message", which just prints the error message without
1725 ** A prompt substitution hook (prompt_hook) is now available to the
1728 ** A new Python module, gdb.prompt has been added to the GDB Python
1729 modules library. This module provides functionality for
1730 escape sequences in prompts (used by set/show
1731 extended-prompt). These escape sequences are replaced by their
1732 corresponding value.
1734 ** Python commands and convenience-functions located in
1735 'data-directory'/python/gdb/command and
1736 'data-directory'/python/gdb/function are now automatically loaded
1739 ** Blocks now provide four new attributes. global_block and
1740 static_block will return the global and static blocks
1741 respectively. is_static and is_global are boolean attributes
1742 that indicate if the block is one of those two types.
1744 ** Symbols now provide the "type" attribute, the type of the symbol.
1746 ** The "gdb.breakpoint" function has been deprecated in favor of
1749 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1750 of a function. This class is based on the "finish" command
1751 available in the CLI.
1753 ** Type objects for struct and union types now allow access to
1754 the fields using standard Python dictionary (mapping) methods.
1755 For example, "some_type['myfield']" now works, as does
1756 "some_type.items()".
1758 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1761 ** A new function, "deep_items" has been added to the gdb.types
1762 module in the GDB Python modules library. This function returns
1763 an iterator over the fields of a struct or union type. Unlike
1764 the standard Python "iteritems" method, it will recursively traverse
1765 any anonymous fields.
1769 ** "*stopped" events can report several new "reason"s, such as
1772 ** Breakpoint changes are now notified using new async records, like
1773 "=breakpoint-modified".
1775 ** New command -ada-task-info.
1777 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1778 $sdir specifies the default system locations of shared libraries.
1779 $pdir specifies the directory where the libpthread used by the application
1782 GDB no longer looks in $sdir and $pdir after it has searched the directories
1783 mentioned in libthread-db-search-path. If you want to search those
1784 directories, they must be specified in libthread-db-search-path.
1785 The default value of libthread-db-search-path on GNU/Linux and Solaris
1786 systems is now "$sdir:$pdir".
1788 $pdir is not supported by gdbserver, it is currently ignored.
1789 $sdir is supported by gdbserver.
1791 * New configure option --with-iconv-bin.
1792 When using the internationalization support like the one in the GNU C
1793 library, GDB will invoke the "iconv" program to get a list of supported
1794 character sets. If this program lives in a non-standard location, one can
1795 use this option to specify where to find it.
1797 * When natively debugging programs on PowerPC BookE processors running
1798 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1799 watchpoints, which specify a mask in addition to an address to watch.
1800 The mask specifies that some bits of an address (the bits which are
1801 reset in the mask) should be ignored when matching the address accessed
1802 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1803 section in the user manual for more details.
1805 * The new option --once causes GDBserver to stop listening for connections once
1806 the first connection is made. The listening port used by GDBserver will
1807 become available after that.
1809 * New commands "info macros" and "alias" have been added.
1811 * New function parameters suffix @entry specifies value of function parameter
1812 at the time the function got called. Entry values are available only since
1818 "!" is now an alias of the "shell" command.
1819 Note that no space is needed between "!" and SHELL COMMAND.
1823 watch EXPRESSION mask MASK_VALUE
1824 The watch command now supports the mask argument which allows creation
1825 of masked watchpoints, if the current architecture supports this feature.
1827 info auto-load-scripts [REGEXP]
1828 This command was formerly named "maintenance print section-scripts".
1829 It is now generally useful and is no longer a maintenance-only command.
1831 info macro [-all] [--] MACRO
1832 The info macro command has new options `-all' and `--'. The first for
1833 printing all definitions of a macro. The second for explicitly specifying
1834 the end of arguments and the beginning of the macro name in case the macro
1835 name starts with a hyphen.
1837 collect[/s] EXPRESSIONS
1838 The tracepoint collect command now takes an optional modifier "/s"
1839 that directs it to dereference pointer-to-character types and
1840 collect the bytes of memory up to a zero byte. The behavior is
1841 similar to what you see when you use the regular print command on a
1842 string. An optional integer following the "/s" sets a bound on the
1843 number of bytes that will be collected.
1846 The trace start command now interprets any supplied arguments as a
1847 note to be recorded with the trace run, with an effect similar to
1848 setting the variable trace-notes.
1851 The trace stop command now interprets any arguments as a note to be
1852 mentioned along with the tstatus report that the trace was stopped
1853 with a command. The effect is similar to setting the variable
1856 * Tracepoints can now be enabled and disabled at any time after a trace
1857 experiment has been started using the standard "enable" and "disable"
1858 commands. It is now possible to start a trace experiment with no enabled
1859 tracepoints; GDB will display a warning, but will allow the experiment to
1860 begin, assuming that tracepoints will be enabled as needed while the trace
1863 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1864 locations with 4-byte instructions, when they were previously
1865 limited to locations with instructions of 5 bytes or longer.
1869 set debug dwarf2-read
1870 show debug dwarf2-read
1871 Turns on or off display of debugging messages related to reading
1872 DWARF debug info. The default is off.
1874 set debug symtab-create
1875 show debug symtab-create
1876 Turns on or off display of debugging messages related to symbol table
1877 creation. The default is off.
1880 show extended-prompt
1881 Set the GDB prompt, and allow escape sequences to be inserted to
1882 display miscellaneous information (see 'help set extended-prompt'
1883 for the list of sequences). This prompt (and any information
1884 accessed through the escape sequences) is updated every time the
1885 prompt is displayed.
1887 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1888 show print entry-values
1889 Set printing of frame argument values at function entry. In some cases
1890 GDB can determine the value of function argument which was passed by the
1891 function caller, even if the value was modified inside the called function.
1893 set debug entry-values
1894 show debug entry-values
1895 Control display of debugging info for determining frame argument values at
1896 function entry and virtual tail call frames.
1898 set basenames-may-differ
1899 show basenames-may-differ
1900 Set whether a source file may have multiple base names.
1901 (A "base name" is the name of a file with the directory part removed.
1902 Example: The base name of "/home/user/hello.c" is "hello.c".)
1903 If set, GDB will canonicalize file names (e.g., expand symlinks)
1904 before comparing them. Canonicalization is an expensive operation,
1905 but it allows the same file be known by more than one base name.
1906 If not set (the default), all source files are assumed to have just
1907 one base name, and gdb will do file name comparisons more efficiently.
1913 Set a user name and notes for the current and any future trace runs.
1914 This is useful for long-running and/or disconnected traces, to
1915 inform others (or yourself) as to who is running the trace, supply
1916 contact information, or otherwise explain what is going on.
1918 set trace-stop-notes
1919 show trace-stop-notes
1920 Set a note attached to the trace run, that is displayed when the
1921 trace has been stopped by a tstop command. This is useful for
1922 instance as an explanation, if you are stopping a trace run that was
1923 started by someone else.
1925 * New remote packets
1929 Dynamically enable a tracepoint in a started trace experiment.
1933 Dynamically disable a tracepoint in a started trace experiment.
1937 Set the user and notes of the trace run.
1941 Query the current status of a tracepoint.
1945 Query the minimum length of instruction at which a fast tracepoint may
1948 * Dcache size (number of lines) and line-size are now runtime-configurable
1949 via "set dcache line" and "set dcache line-size" commands.
1953 Texas Instruments TMS320C6x tic6x-*-*
1957 Renesas RL78 rl78-*-elf
1959 *** Changes in GDB 7.3.1
1961 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1963 *** Changes in GDB 7.3
1965 * GDB has a new command: "thread find [REGEXP]".
1966 It finds the thread id whose name, target id, or thread extra info
1967 matches the given regular expression.
1969 * The "catch syscall" command now works on mips*-linux* targets.
1971 * The -data-disassemble MI command now supports modes 2 and 3 for
1972 dumping the instruction opcodes.
1974 * New command line options
1976 -data-directory DIR Specify DIR as the "data-directory".
1977 This is mostly for testing purposes.
1979 * The "maint set python auto-load on|off" command has been renamed to
1980 "set auto-load-scripts on|off".
1982 * GDB has a new command: "set directories".
1983 It is like the "dir" command except that it replaces the
1984 source path list instead of augmenting it.
1986 * GDB now understands thread names.
1988 On GNU/Linux, "info threads" will display the thread name as set by
1989 prctl or pthread_setname_np.
1991 There is also a new command, "thread name", which can be used to
1992 assign a name internally for GDB to display.
1995 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1996 has been integrated into GDB.
2000 ** The function gdb.Write now accepts an optional keyword 'stream'.
2001 This keyword, when provided, will direct the output to either
2002 stdout, stderr, or GDB's logging output.
2004 ** Parameters can now be be sub-classed in Python, and in particular
2005 you may implement the get_set_doc and get_show_doc functions.
2006 This improves how Parameter set/show documentation is processed
2007 and allows for more dynamic content.
2009 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2010 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2011 have an is_valid method.
2013 ** Breakpoints can now be sub-classed in Python, and in particular
2014 you may implement a 'stop' function that is executed each time
2015 the inferior reaches that breakpoint.
2017 ** New function gdb.lookup_global_symbol looks up a global symbol.
2019 ** GDB values in Python are now callable if the value represents a
2020 function. For example, if 'some_value' represents a function that
2021 takes two integer parameters and returns a value, you can call
2022 that function like so:
2024 result = some_value (10,20)
2026 ** Module gdb.types has been added.
2027 It contains a collection of utilities for working with gdb.Types objects:
2028 get_basic_type, has_field, make_enum_dict.
2030 ** Module gdb.printing has been added.
2031 It contains utilities for writing and registering pretty-printers.
2032 New classes: PrettyPrinter, SubPrettyPrinter,
2033 RegexpCollectionPrettyPrinter.
2034 New function: register_pretty_printer.
2036 ** New commands "info pretty-printers", "enable pretty-printer" and
2037 "disable pretty-printer" have been added.
2039 ** gdb.parameter("directories") is now available.
2041 ** New function gdb.newest_frame returns the newest frame in the
2044 ** The gdb.InferiorThread class has a new "name" attribute. This
2045 holds the thread's name.
2047 ** Python Support for Inferior events.
2048 Python scripts can add observers to be notified of events
2049 occurring in the process being debugged.
2050 The following events are currently supported:
2051 - gdb.events.cont Continue event.
2052 - gdb.events.exited Inferior exited event.
2053 - gdb.events.stop Signal received, and Breakpoint hit events.
2057 ** GDB now puts template parameters in scope when debugging in an
2058 instantiation. For example, if you have:
2060 template<int X> int func (void) { return X; }
2062 then if you step into func<5>, "print X" will show "5". This
2063 feature requires proper debuginfo support from the compiler; it
2064 was added to GCC 4.5.
2066 ** The motion commands "next", "finish", "until", and "advance" now
2067 work better when exceptions are thrown. In particular, GDB will
2068 no longer lose control of the inferior; instead, the GDB will
2069 stop the inferior at the point at which the exception is caught.
2070 This functionality requires a change in the exception handling
2071 code that was introduced in GCC 4.5.
2073 * GDB now follows GCC's rules on accessing volatile objects when
2074 reading or writing target state during expression evaluation.
2075 One notable difference to prior behavior is that "print x = 0"
2076 no longer generates a read of x; the value of the assignment is
2077 now always taken directly from the value being assigned.
2079 * GDB now has some support for using labels in the program's source in
2080 linespecs. For instance, you can use "advance label" to continue
2081 execution to a label.
2083 * GDB now has support for reading and writing a new .gdb_index
2084 section. This section holds a fast index of DWARF debugging
2085 information and can be used to greatly speed up GDB startup and
2086 operation. See the documentation for `save gdb-index' for details.
2088 * The "watch" command now accepts an optional "-location" argument.
2089 When used, this causes GDB to watch the memory referred to by the
2090 expression. Such a watchpoint is never deleted due to it going out
2093 * GDB now supports thread debugging of core dumps on GNU/Linux.
2095 GDB now activates thread debugging using the libthread_db library
2096 when debugging GNU/Linux core dumps, similarly to when debugging
2097 live processes. As a result, when debugging a core dump file, GDB
2098 is now able to display pthread_t ids of threads. For example, "info
2099 threads" shows the same output as when debugging the process when it
2100 was live. In earlier releases, you'd see something like this:
2103 * 1 LWP 6780 main () at main.c:10
2105 While now you see this:
2108 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2110 It is also now possible to inspect TLS variables when debugging core
2113 When debugging a core dump generated on a machine other than the one
2114 used to run GDB, you may need to point GDB at the correct
2115 libthread_db library with the "set libthread-db-search-path"
2116 command. See the user manual for more details on this command.
2118 * When natively debugging programs on PowerPC BookE processors running
2119 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2120 which stop execution of the inferior whenever it executes an instruction
2121 at any address within the specified range. See the "PowerPC Embedded"
2122 section in the user manual for more details.
2124 * New features in the GDB remote stub, GDBserver
2126 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2127 and i686 LynxOS (version 5.x).
2129 ** GDBserver is now supported on Blackfin Linux.
2131 * New native configurations
2133 ia64 HP-UX ia64-*-hpux*
2137 Analog Devices, Inc. Blackfin Processor bfin-*
2139 * Ada task switching is now supported on sparc-elf targets when
2140 debugging a program using the Ravenscar Profile. For more information,
2141 see the "Tasking Support when using the Ravenscar Profile" section
2142 in the GDB user manual.
2144 * Guile support was removed.
2146 * New features in the GNU simulator
2148 ** The --map-info flag lists all known core mappings.
2150 ** CFI flashes may be simulated via the "cfi" device.
2152 *** Changes in GDB 7.2
2154 * Shared library support for remote targets by default
2156 When GDB is configured for a generic, non-OS specific target, like
2157 for example, --target=arm-eabi or one of the many *-*-elf targets,
2158 GDB now queries remote stubs for loaded shared libraries using the
2159 `qXfer:libraries:read' packet. Previously, shared library support
2160 was always disabled for such configurations.
2164 ** Argument Dependent Lookup (ADL)
2166 In C++ ADL lookup directs function search to the namespaces of its
2167 arguments even if the namespace has not been imported.
2177 Here the compiler will search for `foo' in the namespace of 'b'
2178 and find A::foo. GDB now supports this. This construct is commonly
2179 used in the Standard Template Library for operators.
2181 ** Improved User Defined Operator Support
2183 In addition to member operators, GDB now supports lookup of operators
2184 defined in a namespace and imported with a `using' directive, operators
2185 defined in the global scope, operators imported implicitly from an
2186 anonymous namespace, and the ADL operators mentioned in the previous
2188 GDB now also supports proper overload resolution for all the previously
2189 mentioned flavors of operators.
2191 ** static const class members
2193 Printing of static const class members that are initialized in the
2194 class definition has been fixed.
2196 * Windows Thread Information Block access.
2198 On Windows targets, GDB now supports displaying the Windows Thread
2199 Information Block (TIB) structure. This structure is visible either
2200 by using the new command `info w32 thread-information-block' or, by
2201 dereferencing the new convenience variable named `$_tlb', a
2202 thread-specific pointer to the TIB. This feature is also supported
2203 when remote debugging using GDBserver.
2205 * Static tracepoints
2207 Static tracepoints are calls in the user program into a tracing
2208 library. One such library is a port of the LTTng kernel tracer to
2209 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2210 When debugging with GDBserver, GDB now supports combining the GDB
2211 tracepoint machinery with such libraries. For example: the user can
2212 use GDB to probe a static tracepoint marker (a call from the user
2213 program into the tracing library) with the new "strace" command (see
2214 "New commands" below). This creates a "static tracepoint" in the
2215 breakpoint list, that can be manipulated with the same feature set
2216 as fast and regular tracepoints. E.g., collect registers, local and
2217 global variables, collect trace state variables, and define
2218 tracepoint conditions. In addition, the user can collect extra
2219 static tracepoint marker specific data, by collecting the new
2220 $_sdata internal variable. When analyzing the trace buffer, you can
2221 inspect $_sdata like any other variable available to GDB. For more
2222 information, see the "Tracepoints" chapter in GDB user manual. New
2223 remote packets have been defined to support static tracepoints, see
2224 the "New remote packets" section below.
2226 * Better reconstruction of tracepoints after disconnected tracing
2228 GDB will attempt to download the original source form of tracepoint
2229 definitions when starting a trace run, and then will upload these
2230 upon reconnection to the target, resulting in a more accurate
2231 reconstruction of the tracepoints that are in use on the target.
2235 You can now exercise direct control over the ways that GDB can
2236 affect your program. For instance, you can disallow the setting of
2237 breakpoints, so that the program can run continuously (assuming
2238 non-stop mode). In addition, the "observer" variable is available
2239 to switch all of the different controls; in observer mode, GDB
2240 cannot affect the target's behavior at all, which is useful for
2241 tasks like diagnosing live systems in the field.
2243 * The new convenience variable $_thread holds the number of the
2246 * New remote packets
2250 Return the address of the Windows Thread Information Block of a given thread.
2254 In response to several of the tracepoint packets, the target may now
2255 also respond with a number of intermediate `qRelocInsn' request
2256 packets before the final result packet, to have GDB handle
2257 relocating an instruction to execute at a different address. This
2258 is particularly useful for stubs that support fast tracepoints. GDB
2259 reports support for this feature in the qSupported packet.
2263 List static tracepoint markers in the target program.
2267 List static tracepoint markers at a given address in the target
2270 qXfer:statictrace:read
2272 Read the static trace data collected (by a `collect $_sdata'
2273 tracepoint action). The remote stub reports support for this packet
2274 to gdb's qSupported query.
2278 Send the current settings of GDB's permission flags.
2282 Send part of the source (textual) form of a tracepoint definition,
2283 which includes location, conditional, and action list.
2285 * The source command now accepts a -s option to force searching for the
2286 script in the source search path even if the script name specifies
2289 * New features in the GDB remote stub, GDBserver
2291 - GDBserver now support tracepoints (including fast tracepoints, and
2292 static tracepoints). The feature is currently supported by the
2293 i386-linux and amd64-linux builds. See the "Tracepoints support
2294 in gdbserver" section in the manual for more information.
2296 GDBserver JIT compiles the tracepoint's conditional agent
2297 expression bytecode into native code whenever possible for low
2298 overhead dynamic tracepoints conditionals. For such tracepoints,
2299 an expression that examines program state is evaluated when the
2300 tracepoint is reached, in order to determine whether to capture
2301 trace data. If the condition is simple and false, processing the
2302 tracepoint finishes very quickly and no data is gathered.
2304 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2305 for static tracepoints support.
2307 - GDBserver now supports x86_64 Windows 64-bit debugging.
2309 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2310 it understands register description.
2312 * The --batch flag now disables pagination and queries.
2314 * X86 general purpose registers
2316 GDB now supports reading/writing byte, word and double-word x86
2317 general purpose registers directly. This means you can use, say,
2318 $ah or $ax to refer, respectively, to the byte register AH and
2319 16-bit word register AX that are actually portions of the 32-bit
2320 register EAX or 64-bit register RAX.
2322 * The `commands' command now accepts a range of breakpoints to modify.
2323 A plain `commands' following a command that creates multiple
2324 breakpoints affects all the breakpoints set by that command. This
2325 applies to breakpoints set by `rbreak', and also applies when a
2326 single `break' command creates multiple breakpoints (e.g.,
2327 breakpoints on overloaded c++ functions).
2329 * The `rbreak' command now accepts a filename specification as part of
2330 its argument, limiting the functions selected by the regex to those
2331 in the specified file.
2333 * Support for remote debugging Windows and SymbianOS shared libraries
2334 from Unix hosts has been improved. Non Windows GDB builds now can
2335 understand target reported file names that follow MS-DOS based file
2336 system semantics, such as file names that include drive letters and
2337 use the backslash character as directory separator. This makes it
2338 possible to transparently use the "set sysroot" and "set
2339 solib-search-path" on Unix hosts to point as host copies of the
2340 target's shared libraries. See the new command "set
2341 target-file-system-kind" described below, and the "Commands to
2342 specify files" section in the user manual for more information.
2346 eval template, expressions...
2347 Convert the values of one or more expressions under the control
2348 of the string template to a command line, and call it.
2350 set target-file-system-kind unix|dos-based|auto
2351 show target-file-system-kind
2352 Set or show the assumed file system kind for target reported file
2355 save breakpoints <filename>
2356 Save all current breakpoint definitions to a file suitable for use
2357 in a later debugging session. To read the saved breakpoint
2358 definitions, use the `source' command.
2360 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2363 info static-tracepoint-markers
2364 Display information about static tracepoint markers in the target.
2366 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2367 Define a static tracepoint by probing a marker at the given
2368 function, line, address, or marker ID.
2372 Enable and disable observer mode.
2374 set may-write-registers on|off
2375 set may-write-memory on|off
2376 set may-insert-breakpoints on|off
2377 set may-insert-tracepoints on|off
2378 set may-insert-fast-tracepoints on|off
2379 set may-interrupt on|off
2380 Set individual permissions for GDB effects on the target. Note that
2381 some of these settings can have undesirable or surprising
2382 consequences, particularly when changed in the middle of a session.
2383 For instance, disabling the writing of memory can prevent
2384 breakpoints from being inserted, cause single-stepping to fail, or
2385 even crash your program, if you disable after breakpoints have been
2386 inserted. However, GDB should not crash.
2388 set record memory-query on|off
2389 show record memory-query
2390 Control whether to stop the inferior if memory changes caused
2391 by an instruction cannot be recorded.
2396 The disassemble command now supports "start,+length" form of two arguments.
2400 ** GDB now provides a new directory location, called the python directory,
2401 where Python scripts written for GDB can be installed. The location
2402 of that directory is <data-directory>/python, where <data-directory>
2403 is the GDB data directory. For more details, see section `Scripting
2404 GDB using Python' in the manual.
2406 ** The GDB Python API now has access to breakpoints, symbols, symbol
2407 tables, program spaces, inferiors, threads and frame's code blocks.
2408 Additionally, GDB Parameters can now be created from the API, and
2409 manipulated via set/show in the CLI.
2411 ** New functions gdb.target_charset, gdb.target_wide_charset,
2412 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2414 ** New exception gdb.GdbError.
2416 ** Pretty-printers are now also looked up in the current program space.
2418 ** Pretty-printers can now be individually enabled and disabled.
2420 ** GDB now looks for names of Python scripts to auto-load in a
2421 special section named `.debug_gdb_scripts', in addition to looking
2422 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2424 * Tracepoint actions were unified with breakpoint commands. In particular,
2425 there are no longer differences in "info break" output for breakpoints and
2426 tracepoints and the "commands" command can be used for both tracepoints and
2427 regular breakpoints.
2431 ARM Symbian arm*-*-symbianelf*
2433 * D language support.
2434 GDB now supports debugging programs written in the D programming
2437 * GDB now supports the extended ptrace interface for PowerPC which is
2438 available since Linux kernel version 2.6.34. This automatically enables
2439 any hardware breakpoints and additional hardware watchpoints available in
2440 the processor. The old ptrace interface exposes just one hardware
2441 watchpoint and no hardware breakpoints.
2443 * GDB is now able to use the Data Value Compare (DVC) register available on
2444 embedded PowerPC processors to implement in hardware simple watchpoint
2445 conditions of the form:
2447 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2449 This works in native GDB running on Linux kernels with the extended ptrace
2450 interface mentioned above.
2452 *** Changes in GDB 7.1
2456 ** Namespace Support
2458 GDB now supports importing of namespaces in C++. This enables the
2459 user to inspect variables from imported namespaces. Support for
2460 namepace aliasing has also been added. So, if a namespace is
2461 aliased in the current scope (e.g. namepace C=A; ) the user can
2462 print variables using the alias (e.g. (gdb) print C::x).
2466 All known bugs relating to the printing of virtual base class were
2467 fixed. It is now possible to call overloaded static methods using a
2472 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2473 and reinterpret_cast<> are now handled by the C++ expression parser.
2477 Xilinx MicroBlaze microblaze-*-*
2482 Xilinx MicroBlaze microblaze
2485 * Multi-program debugging.
2487 GDB now has support for multi-program (a.k.a. multi-executable or
2488 multi-exec) debugging. This allows for debugging multiple inferiors
2489 simultaneously each running a different program under the same GDB
2490 session. See "Debugging Multiple Inferiors and Programs" in the
2491 manual for more information. This implied some user visible changes
2492 in the multi-inferior support. For example, "info inferiors" now
2493 lists inferiors that are not running yet or that have exited
2494 already. See also "New commands" and "New options" below.
2496 * New tracing features
2498 GDB's tracepoint facility now includes several new features:
2500 ** Trace state variables
2502 GDB tracepoints now include support for trace state variables, which
2503 are variables managed by the target agent during a tracing
2504 experiment. They are useful for tracepoints that trigger each
2505 other, so for instance one tracepoint can count hits in a variable,
2506 and then a second tracepoint has a condition that is true when the
2507 count reaches a particular value. Trace state variables share the
2508 $-syntax of GDB convenience variables, and can appear in both
2509 tracepoint actions and condition expressions. Use the "tvariable"
2510 command to create, and "info tvariables" to view; see "Trace State
2511 Variables" in the manual for more detail.
2515 GDB now includes an option for defining fast tracepoints, which
2516 targets may implement more efficiently, such as by installing a jump
2517 into the target agent rather than a trap instruction. The resulting
2518 speedup can be by two orders of magnitude or more, although the
2519 tradeoff is that some program locations on some target architectures
2520 might not allow fast tracepoint installation, for instance if the
2521 instruction to be replaced is shorter than the jump. To request a
2522 fast tracepoint, use the "ftrace" command, with syntax identical to
2523 the regular trace command.
2525 ** Disconnected tracing
2527 It is now possible to detach GDB from the target while it is running
2528 a trace experiment, then reconnect later to see how the experiment
2529 is going. In addition, a new variable disconnected-tracing lets you
2530 tell the target agent whether to continue running a trace if the
2531 connection is lost unexpectedly.
2535 GDB now has the ability to save the trace buffer into a file, and
2536 then use that file as a target, similarly to you can do with
2537 corefiles. You can select trace frames, print data that was
2538 collected in them, and use tstatus to display the state of the
2539 tracing run at the moment that it was saved. To create a trace
2540 file, use "tsave <filename>", and to use it, do "target tfile
2543 ** Circular trace buffer
2545 You can ask the target agent to handle the trace buffer as a
2546 circular buffer, discarding the oldest trace frames to make room for
2547 newer ones, by setting circular-trace-buffer to on. This feature may
2548 not be available for all target agents.
2553 The disassemble command, when invoked with two arguments, now requires
2554 the arguments to be comma-separated.
2557 The info variables command now displays variable definitions. Files
2558 which only declare a variable are not shown.
2561 The source command is now capable of sourcing Python scripts.
2562 This feature is dependent on the debugger being build with Python
2565 Related to this enhancement is also the introduction of a new command
2566 "set script-extension" (see below).
2568 * New commands (for set/show, see "New options" below)
2570 record save [<FILENAME>]
2571 Save a file (in core file format) containing the process record
2572 execution log for replay debugging at a later time.
2574 record restore <FILENAME>
2575 Restore the process record execution log that was saved at an
2576 earlier time, for replay debugging.
2578 add-inferior [-copies <N>] [-exec <FILENAME>]
2581 clone-inferior [-copies <N>] [ID]
2582 Make a new inferior ready to execute the same program another
2583 inferior has loaded.
2588 maint info program-spaces
2589 List the program spaces loaded into GDB.
2591 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2592 show remote interrupt-sequence
2593 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2594 as the sequence to the remote target in order to interrupt the execution.
2595 Ctrl-C is a default. Some system prefers BREAK which is high level of
2596 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2597 Magic SysRq g. It is BREAK signal and character 'g'.
2599 set remote interrupt-on-connect [on | off]
2600 show remote interrupt-on-connect
2601 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2602 remote target when gdb connects to it. This is needed when you debug
2605 set remotebreak [on | off]
2607 Deprecated. Use "set/show remote interrupt-sequence" instead.
2609 tvariable $NAME [ = EXP ]
2610 Create or modify a trace state variable.
2613 List trace state variables and their values.
2615 delete tvariable $NAME ...
2616 Delete one or more trace state variables.
2619 Evaluate the given expressions without collecting anything into the
2620 trace buffer. (Valid in tracepoint actions only.)
2622 ftrace FN / FILE:LINE / *ADDR
2623 Define a fast tracepoint at the given function, line, or address.
2625 * New expression syntax
2627 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2628 GDB now parses 0b101010 identically with 42.
2632 set follow-exec-mode new|same
2633 show follow-exec-mode
2634 Control whether GDB reuses the same inferior across an exec call or
2635 creates a new one. This is useful to be able to restart the old
2636 executable after the inferior having done an exec call.
2638 set default-collect EXPR, ...
2639 show default-collect
2640 Define a list of expressions to be collected at each tracepoint.
2641 This is a useful way to ensure essential items are not overlooked,
2642 such as registers or a critical global variable.
2644 set disconnected-tracing
2645 show disconnected-tracing
2646 If set to 1, the target is instructed to continue tracing if it
2647 loses its connection to GDB. If 0, the target is to stop tracing
2650 set circular-trace-buffer
2651 show circular-trace-buffer
2652 If set to on, the target is instructed to use a circular trace buffer
2653 and discard the oldest trace frames instead of stopping the trace due
2654 to a full trace buffer. If set to off, the trace stops when the buffer
2655 fills up. Some targets may not support this.
2657 set script-extension off|soft|strict
2658 show script-extension
2659 If set to "off", the debugger does not perform any script language
2660 recognition, and all sourced files are assumed to be GDB scripts.
2661 If set to "soft" (the default), files are sourced according to
2662 filename extension, falling back to GDB scripts if the first
2664 If set to "strict", files are sourced according to filename extension.
2666 set ada trust-PAD-over-XVS on|off
2667 show ada trust-PAD-over-XVS
2668 If off, activate a workaround against a bug in the debugging information
2669 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2670 the GCC sources for more information about the GNAT encoding and
2671 PAD types in particular). It is always safe to set this option to
2672 off, but this introduces a slight performance penalty. The default
2675 * Python API Improvements
2677 ** GDB provides the new class gdb.LazyString. This is useful in
2678 some pretty-printing cases. The new method gdb.Value.lazy_string
2679 provides a simple way to create objects of this type.
2681 ** The fields returned by gdb.Type.fields now have an
2682 `is_base_class' attribute.
2684 ** The new method gdb.Type.range returns the range of an array type.
2686 ** The new method gdb.parse_and_eval can be used to parse and
2687 evaluate an expression.
2689 * New remote packets
2692 Define a trace state variable.
2695 Get the current value of a trace state variable.
2698 Set desired tracing behavior upon disconnection.
2701 Set the trace buffer to be linear or circular.
2704 Get data about the tracepoints currently in use.
2708 Process record now works correctly with hardware watchpoints.
2710 Multiple bug fixes have been made to the mips-irix port, making it
2711 much more reliable. In particular:
2712 - Debugging threaded applications is now possible again. Previously,
2713 GDB would hang while starting the program, or while waiting for
2714 the program to stop at a breakpoint.
2715 - Attaching to a running process no longer hangs.
2716 - An error occurring while loading a core file has been fixed.
2717 - Changing the value of the PC register now works again. This fixes
2718 problems observed when using the "jump" command, or when calling
2719 a function from GDB, or even when assigning a new value to $pc.
2720 - With the "finish" and "return" commands, the return value for functions
2721 returning a small array is now correctly printed.
2722 - It is now possible to break on shared library code which gets executed
2723 during a shared library init phase (code executed while executing
2724 their .init section). Previously, the breakpoint would have no effect.
2725 - GDB is now able to backtrace through the signal handler for
2726 non-threaded programs.
2728 PIE (Position Independent Executable) programs debugging is now supported.
2729 This includes debugging execution of PIC (Position Independent Code) shared
2730 libraries although for that, it should be possible to run such libraries as an
2733 *** Changes in GDB 7.0
2735 * GDB now has an interface for JIT compilation. Applications that
2736 dynamically generate code can create symbol files in memory and register
2737 them with GDB. For users, the feature should work transparently, and
2738 for JIT developers, the interface is documented in the GDB manual in the
2739 "JIT Compilation Interface" chapter.
2741 * Tracepoints may now be conditional. The syntax is as for
2742 breakpoints; either an "if" clause appended to the "trace" command,
2743 or the "condition" command is available. GDB sends the condition to
2744 the target for evaluation using the same bytecode format as is used
2745 for tracepoint actions.
2747 * The disassemble command now supports: an optional /r modifier, print the
2748 raw instructions in hex as well as in symbolic form, and an optional /m
2749 modifier to print mixed source+assembly.
2751 * Process record and replay
2753 In a architecture environment that supports ``process record and
2754 replay'', ``process record and replay'' target can record a log of
2755 the process execution, and replay it with both forward and reverse
2758 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2759 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2760 set execution-direction {forward|reverse}, for targets that support
2763 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2764 feature is available with a native GDB running on kernel version
2767 * GDB now has support for multi-byte and wide character sets on the
2768 target. Strings whose character type is wchar_t, char16_t, or
2769 char32_t are now correctly printed. GDB supports wide- and unicode-
2770 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2771 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2772 `printf'. This feature requires iconv to work properly; if your
2773 system does not have a working iconv, GDB can use GNU libiconv. See
2774 the installation instructions for more information.
2776 * GDB now supports automatic retrieval of shared library files from
2777 remote targets. To use this feature, specify a system root that begins
2778 with the `remote:' prefix, either via the `set sysroot' command or via
2779 the `--with-sysroot' configure-time option.
2781 * "info sharedlibrary" now takes an optional regex of libraries to show,
2782 and it now reports if a shared library has no debugging information.
2784 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2785 now complete on file names.
2787 * When completing in expressions, gdb will attempt to limit
2788 completions to allowable structure or union fields, where appropriate.
2789 For instance, consider:
2791 # struct example { int f1; double f2; };
2792 # struct example variable;
2795 If the user types TAB at the end of this command line, the available
2796 completions will be "f1" and "f2".
2798 * Inlined functions are now supported. They show up in backtraces, and
2799 the "step", "next", and "finish" commands handle them automatically.
2801 * GDB now supports the token-splicing (##) and stringification (#)
2802 operators when expanding macros. It also supports variable-arity
2805 * GDB now supports inspecting extra signal information, exported by
2806 the new $_siginfo convenience variable. The feature is currently
2807 implemented on linux ARM, i386 and amd64.
2809 * GDB can now display the VFP floating point registers and NEON vector
2810 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2811 can provide these registers (requires Linux 2.6.30 or later). Remote
2812 and simulator targets may also provide them.
2814 * New remote packets
2817 Search memory for a sequence of bytes.
2820 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2821 operation over reliable transport links. Use of this packet is
2822 controlled by the `set remote noack-packet' command.
2825 Kill the process with the specified process ID. Use this in preference
2826 to `k' when multiprocess protocol extensions are supported.
2829 Obtains additional operating system information
2833 Read or write additional signal information.
2835 * Removed remote protocol undocumented extension
2837 An undocumented extension to the remote protocol's `S' stop reply
2838 packet that permited the stub to pass a process id was removed.
2839 Remote servers should use the `T' stop reply packet instead.
2841 * GDB now supports multiple function calling conventions according to the
2842 DWARF-2 DW_AT_calling_convention function attribute.
2844 * The SH target utilizes the aforementioned change to distinguish between gcc
2845 and Renesas calling convention. It also adds the new CLI commands
2846 `set/show sh calling-convention'.
2848 * GDB can now read compressed debug sections, as produced by GNU gold
2849 with the --compress-debug-sections=zlib flag.
2851 * 64-bit core files are now supported on AIX.
2853 * Thread switching is now supported on Tru64.
2855 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2856 which will be allocated using malloc later in program execution.
2858 * The qXfer:libraries:read remote procotol packet now allows passing a
2859 list of section offsets.
2861 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2862 conditions handling signals delivered during attach or thread creation
2863 have also been fixed.
2865 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2866 From the user's standpoint, all unqualified instances of True and False
2867 are treated as the standard definitions, regardless of context.
2869 * GDB now parses C++ symbol and type names more flexibly. For
2872 template<typename T> class C { };
2875 GDB will now correctly handle all of:
2877 ptype C<char const *>
2878 ptype C<char const*>
2879 ptype C<const char *>
2880 ptype C<const char*>
2882 * New features in the GDB remote stub, gdbserver
2884 - The "--wrapper" command-line argument tells gdbserver to use a
2885 wrapper program to launch programs for debugging.
2887 - On PowerPC and S/390 targets, it is now possible to use a single
2888 gdbserver executable to debug both 32-bit and 64-bit programs.
2889 (This requires gdbserver itself to be built as a 64-bit executable.)
2891 - gdbserver uses the new noack protocol mode for TCP connections to
2892 reduce communications latency, if also supported and enabled in GDB.
2894 - Support for the sparc64-linux-gnu target is now included in
2897 - The amd64-linux build of gdbserver now supports debugging both
2898 32-bit and 64-bit programs.
2900 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2901 now support hardware watchpoints, and will use them automatically
2906 GDB now has support for scripting using Python. Whether this is
2907 available is determined at configure time.
2909 New GDB commands can now be written in Python.
2911 * Ada tasking support
2913 Ada tasks can now be inspected in GDB. The following commands have
2917 Print the list of Ada tasks.
2919 Print detailed information about task number N.
2921 Print the task number of the current task.
2923 Switch the context of debugging to task number N.
2925 * Support for user-defined prefixed commands. The "define" command can
2926 add new commands to existing prefixes, e.g. "target".
2928 * Multi-inferior, multi-process debugging.
2930 GDB now has generalized support for multi-inferior debugging. See
2931 "Debugging Multiple Inferiors" in the manual for more information.
2932 Although availability still depends on target support, the command
2933 set is more uniform now. The GNU/Linux specific multi-forks support
2934 has been migrated to this new framework. This implied some user
2935 visible changes; see "New commands" and also "Removed commands"
2938 * Target descriptions can now describe the target OS ABI. See the
2939 "Target Description Format" section in the user manual for more
2942 * Target descriptions can now describe "compatible" architectures
2943 to indicate that the target can execute applications for a different
2944 architecture in addition to those for the main target architecture.
2945 See the "Target Description Format" section in the user manual for
2948 * Multi-architecture debugging.
2950 GDB now includes general supports for debugging applications on
2951 hybrid systems that use more than one single processor architecture
2952 at the same time. Each such hybrid architecture still requires
2953 specific support to be added. The only hybrid architecture supported
2954 in this version of GDB is the Cell Broadband Engine.
2956 * GDB now supports integrated debugging of Cell/B.E. applications that
2957 use both the PPU and SPU architectures. To enable support for hybrid
2958 Cell/B.E. debugging, you need to configure GDB to support both the
2959 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2960 --enable-targets configure option.
2962 * Non-stop mode debugging.
2964 For some targets, GDB now supports an optional mode of operation in
2965 which you can examine stopped threads while other threads continue
2966 to execute freely. This is referred to as non-stop mode, with the
2967 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2968 section in the user manual for more information.
2970 To be able to support remote non-stop debugging, a remote stub needs
2971 to implement the non-stop mode remote protocol extensions, as
2972 described in the "Remote Non-Stop" section of the user manual. The
2973 GDB remote stub, gdbserver, has been adjusted to support these
2974 extensions on linux targets.
2976 * New commands (for set/show, see "New options" below)
2978 catch syscall [NAME(S) | NUMBER(S)]
2979 Catch system calls. Arguments, which should be names of system
2980 calls or their numbers, mean catch only those syscalls. Without
2981 arguments, every syscall will be caught. When the inferior issues
2982 any of the specified syscalls, GDB will stop and announce the system
2983 call, both when it is called and when its call returns. This
2984 feature is currently available with a native GDB running on the
2985 Linux Kernel, under the following architectures: x86, x86_64,
2986 PowerPC and PowerPC64.
2988 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2990 Search memory for a sequence of bytes.
2992 maint set python print-stack
2993 maint show python print-stack
2994 Show a stack trace when an error is encountered in a Python script.
2997 Invoke CODE by passing it to the Python interpreter.
3002 These allow macros to be defined, undefined, and listed
3006 Show operating system information about processes.
3009 List the inferiors currently under GDB's control.
3012 Switch focus to inferior number NUM.
3015 Detach from inferior number NUM.
3018 Kill inferior number NUM.
3022 set spu stop-on-load
3023 show spu stop-on-load
3024 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3026 set spu auto-flush-cache
3027 show spu auto-flush-cache
3028 Control whether to automatically flush the software-managed cache
3029 during Cell/B.E. debugging.
3031 set sh calling-convention
3032 show sh calling-convention
3033 Control the calling convention used when calling SH target functions.
3036 show debug timestamp
3037 Control display of timestamps with GDB debugging output.
3039 set disassemble-next-line
3040 show disassemble-next-line
3041 Control display of disassembled source lines or instructions when
3044 set remote noack-packet
3045 show remote noack-packet
3046 Set/show the use of remote protocol QStartNoAckMode packet. See above
3047 under "New remote packets."
3049 set remote query-attached-packet
3050 show remote query-attached-packet
3051 Control use of remote protocol `qAttached' (query-attached) packet.
3053 set remote read-siginfo-object
3054 show remote read-siginfo-object
3055 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3058 set remote write-siginfo-object
3059 show remote write-siginfo-object
3060 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3063 set remote reverse-continue
3064 show remote reverse-continue
3065 Control use of remote protocol 'bc' (reverse-continue) packet.
3067 set remote reverse-step
3068 show remote reverse-step
3069 Control use of remote protocol 'bs' (reverse-step) packet.
3071 set displaced-stepping
3072 show displaced-stepping
3073 Control displaced stepping mode. Displaced stepping is a way to
3074 single-step over breakpoints without removing them from the debuggee.
3075 Also known as "out-of-line single-stepping".
3078 show debug displaced
3079 Control display of debugging info for displaced stepping.
3081 maint set internal-error
3082 maint show internal-error
3083 Control what GDB does when an internal error is detected.
3085 maint set internal-warning
3086 maint show internal-warning
3087 Control what GDB does when an internal warning is detected.
3092 Use a wrapper program to launch programs for debugging.
3094 set multiple-symbols (all|ask|cancel)
3095 show multiple-symbols
3096 The value of this variable can be changed to adjust the debugger behavior
3097 when an expression or a breakpoint location contains an ambiguous symbol
3098 name (an overloaded function name, for instance).
3100 set breakpoint always-inserted
3101 show breakpoint always-inserted
3102 Keep breakpoints always inserted in the target, as opposed to inserting
3103 them when resuming the target, and removing them when the target stops.
3104 This option can improve debugger performance on slow remote targets.
3106 set arm fallback-mode (arm|thumb|auto)
3107 show arm fallback-mode
3108 set arm force-mode (arm|thumb|auto)
3110 These commands control how ARM GDB determines whether instructions
3111 are ARM or Thumb. The default for both settings is auto, which uses
3112 the current CPSR value for instructions without symbols; previous
3113 versions of GDB behaved as if "set arm fallback-mode arm".
3115 set disable-randomization
3116 show disable-randomization
3117 Standalone programs run with the virtual address space randomization enabled
3118 by default on some platforms. This option keeps the addresses stable across
3119 multiple debugging sessions.
3123 Control whether other threads are stopped or not when some thread hits
3128 Requests that asynchronous execution is enabled in the target, if available.
3129 In this case, it's possible to resume target in the background, and interact
3130 with GDB while the target is running. "show target-async" displays the
3131 current state of asynchronous execution of the target.
3133 set target-wide-charset
3134 show target-wide-charset
3135 The target-wide-charset is the name of the character set that GDB
3136 uses when printing characters whose type is wchar_t.
3138 set tcp auto-retry (on|off)
3140 set tcp connect-timeout
3141 show tcp connect-timeout
3142 These commands allow GDB to retry failed TCP connections to a remote stub
3143 with a specified timeout period; this is useful if the stub is launched
3144 in parallel with GDB but may not be ready to accept connections immediately.
3146 set libthread-db-search-path
3147 show libthread-db-search-path
3148 Control list of directories which GDB will search for appropriate
3151 set schedule-multiple (on|off)
3152 show schedule-multiple
3153 Allow GDB to resume all threads of all processes or only threads of
3154 the current process.
3158 Use more aggressive caching for accesses to the stack. This improves
3159 performance of remote debugging (particularly backtraces) without
3160 affecting correctness.
3162 set interactive-mode (on|off|auto)
3163 show interactive-mode
3164 Control whether GDB runs in interactive mode (on) or not (off).
3165 When in interactive mode, GDB waits for the user to answer all
3166 queries. Otherwise, GDB does not wait and assumes the default
3167 answer. When set to auto (the default), GDB determines which
3168 mode to use based on the stdin settings.
3173 For program forks, this is replaced by the new more generic `info
3174 inferiors' command. To list checkpoints, you can still use the
3175 `info checkpoints' command, which was an alias for the `info forks'
3179 Replaced by the new `inferior' command. To switch between
3180 checkpoints, you can still use the `restart' command, which was an
3181 alias for the `fork' command.
3184 This is removed, since some targets don't have a notion of
3185 processes. To switch between processes, you can still use the
3186 `inferior' command using GDB's own inferior number.
3189 For program forks, this is replaced by the new more generic `kill
3190 inferior' command. To delete a checkpoint, you can still use the
3191 `delete checkpoint' command, which was an alias for the `delete
3195 For program forks, this is replaced by the new more generic `detach
3196 inferior' command. To detach a checkpoint, you can still use the
3197 `detach checkpoint' command, which was an alias for the `detach
3200 * New native configurations
3202 x86/x86_64 Darwin i[34567]86-*-darwin*
3204 x86_64 MinGW x86_64-*-mingw*
3208 Lattice Mico32 lm32-*
3209 x86 DICOS i[34567]86-*-dicos*
3210 x86_64 DICOS x86_64-*-dicos*
3213 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3214 (mingw32ce) debugging.
3220 These commands were actually not implemented on any target.
3222 *** Changes in GDB 6.8
3224 * New native configurations
3226 NetBSD/hppa hppa*-*netbsd*
3227 Xtensa GNU/Linux xtensa*-*-linux*
3231 NetBSD/hppa hppa*-*-netbsd*
3232 Xtensa GNU/Lunux xtensa*-*-linux*
3234 * Change in command line behavior -- corefiles vs. process ids.
3236 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3237 attaching to process NUMBER fails, GDB no longer attempts to open a
3238 core file named NUMBER. Attaching to a program using the -c option
3239 is no longer supported. Instead, use the '-p' or '--pid' options.
3241 * GDB can now be built as a native debugger for debugging Windows x86
3242 (mingw32) Portable Executable (PE) programs.
3244 * Pending breakpoints no longer change their number when their address
3247 * GDB now supports breakpoints with multiple locations,
3248 including breakpoints on C++ constructors, inside C++ templates,
3249 and in inlined functions.
3251 * GDB's ability to debug optimized code has been improved. GDB more
3252 accurately identifies function bodies and lexical blocks that occupy
3253 more than one contiguous range of addresses.
3255 * Target descriptions can now describe registers for PowerPC.
3257 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3258 registers on PowerPC targets.
3260 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3261 targets even when the libthread_db library is not available.
3263 * The GDB remote stub, gdbserver, now supports the new file transfer
3264 commands (remote put, remote get, and remote delete).
3266 * The GDB remote stub, gdbserver, now supports run and attach in
3267 extended-remote mode.
3269 * hppa*64*-*-hpux11* target broken
3270 The debugger is unable to start a program and fails with the following
3271 error: "Error trying to get information about dynamic linker".
3272 The gdb-6.7 release is also affected.
3274 * GDB now supports the --enable-targets= configure option to allow
3275 building a single GDB executable that supports multiple remote
3276 target architectures.
3278 * GDB now supports debugging C and C++ programs which use the
3279 Decimal Floating Point extension. In addition, the PowerPC target
3280 now has a set of pseudo-registers to inspect decimal float values
3281 stored in two consecutive float registers.
3283 * The -break-insert MI command can optionally create pending
3286 * Improved support for debugging Ada
3287 Many improvements to the Ada language support have been made. These
3289 - Better support for Ada2005 interface types
3290 - Improved handling of arrays and slices in general
3291 - Better support for Taft-amendment types
3292 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3294 - Improved command completion in Ada
3297 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3302 set print frame-arguments (all|scalars|none)
3303 show print frame-arguments
3304 The value of this variable can be changed to control which argument
3305 values should be printed by the debugger when displaying a frame.
3310 Transfer files to and from a remote target, and delete remote files.
3317 Transfer files to and from a remote target, and delete remote files.
3319 * New remote packets
3326 Open, close, read, write, and delete files on the remote system.
3329 Attach to an existing process on the remote system, in extended-remote
3333 Run a new process on the remote system, in extended-remote mode.
3335 *** Changes in GDB 6.7
3337 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3338 bfd, libiberty and opcodes, as revealed by static analysis donated by
3339 Coverity, Inc. (http://scan.coverity.com).
3341 * When looking up multiply-defined global symbols, GDB will now prefer the
3342 symbol definition in the current shared library if it was built using the
3343 -Bsymbolic linker option.
3345 * When the Text User Interface (TUI) is not configured, GDB will now
3346 recognize the -tui command-line option and print a message that the TUI
3349 * The GDB remote stub, gdbserver, now has lower overhead for high
3350 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3352 * GDB for MIPS targets now autodetects whether a remote target provides
3353 32-bit or 64-bit register values.
3355 * Support for C++ member pointers has been improved.
3357 * GDB now understands XML target descriptions, which specify the
3358 target's overall architecture. GDB can read a description from
3359 a local file or over the remote serial protocol.
3361 * Vectors of single-byte data use a new integer type which is not
3362 automatically displayed as character or string data.
3364 * The /s format now works with the print command. It displays
3365 arrays of single-byte integers and pointers to single-byte integers
3368 * Target descriptions can now describe target-specific registers,
3369 for architectures which have implemented the support (currently
3370 only ARM, M68K, and MIPS).
3372 * GDB and the GDB remote stub, gdbserver, now support the XScale
3375 * The GDB remote stub, gdbserver, has been updated to support
3376 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3377 has been rewritten to use the standard GDB remote protocol.
3379 * GDB can now step into C++ functions which are called through thunks.
3381 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3383 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3384 layout. It also supports a TextSeg= and DataSeg= response when only
3385 segment base addresses (rather than offsets) are available.
3387 * The /i format now outputs any trailing branch delay slot instructions
3388 immediately following the last instruction within the count specified.
3390 * The GDB remote protocol "T" stop reply packet now supports a
3391 "library" response. Combined with the new "qXfer:libraries:read"
3392 packet, this response allows GDB to debug shared libraries on targets
3393 where the operating system manages the list of loaded libraries (e.g.
3394 Windows and SymbianOS).
3396 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3397 (DLLs) on Windows and Windows CE targets.
3399 * GDB now supports a faster verification that a .debug file matches its binary
3400 according to its build-id signature, if the signature is present.
3406 Enable or disable hardware flow control (RTS/CTS) on the serial port
3407 when debugging using remote targets.
3409 set mem inaccessible-by-default
3410 show mem inaccessible-by-default
3411 If the target supplies a memory map, for instance via the remote
3412 protocol's "qXfer:memory-map:read" packet, setting this variable
3413 prevents GDB from accessing memory outside the memory map. This
3414 is useful for targets with memory mapped registers or which react
3415 badly to accesses of unmapped address space.
3417 set breakpoint auto-hw
3418 show breakpoint auto-hw
3419 If the target supplies a memory map, for instance via the remote
3420 protocol's "qXfer:memory-map:read" packet, setting this variable
3421 lets GDB use hardware breakpoints automatically for memory regions
3422 where it can not use software breakpoints. This covers both the
3423 "break" command and internal breakpoints used for other commands
3424 including "next" and "finish".
3427 catch exception unhandled
3428 Stop the program execution when Ada exceptions are raised.
3431 Stop the program execution when an Ada assertion failed.
3435 Set an alternate system root for target files. This is a more
3436 general version of "set solib-absolute-prefix", which is now
3437 an alias to "set sysroot".
3440 Provide extended SPU facility status information. This set of
3441 commands is available only when debugging the Cell/B.E. SPU
3444 * New native configurations
3446 OpenBSD/sh sh*-*openbsd*
3449 unset tdesc filename
3451 Use the specified local file as an XML target description, and do
3452 not query the target for its built-in description.
3456 OpenBSD/sh sh*-*-openbsd*
3457 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3458 Toshiba Media Processor mep-elf
3460 * New remote packets
3463 Ignore the specified signals; pass them directly to the debugged program
3464 without stopping other threads or reporting them to GDB.
3466 qXfer:features:read:
3467 Read an XML target description from the target, which describes its
3472 Read or write contents of an spufs file on the target system. These
3473 packets are available only on the Cell/B.E. SPU architecture.
3475 qXfer:libraries:read:
3476 Report the loaded shared libraries. Combined with new "T" packet
3477 response, this packet allows GDB to debug shared libraries on
3478 targets where the operating system manages the list of loaded
3479 libraries (e.g. Windows and SymbianOS).
3483 Support for these obsolete configurations has been removed.
3491 i[34567]86-*-lynxos*
3492 i[34567]86-*-netware*
3493 i[34567]86-*-sco3.2v5*
3494 i[34567]86-*-sco3.2v4*
3496 i[34567]86-*-sysv4.2*
3499 i[34567]86-*-unixware2*
3500 i[34567]86-*-unixware*
3509 * Other removed features
3516 Various m68k-only ROM monitors.
3523 Various Renesas ROM monitors and debugging interfaces for SH and
3528 Support for a Macraigor serial interface to on-chip debugging.
3529 GDB does not directly support the newer parallel or USB
3534 A debug information format. The predecessor to DWARF 2 and
3535 DWARF 3, which are still supported.
3537 Support for the HP aCC compiler on HP-UX/PA-RISC
3539 SOM-encapsulated symbolic debugging information, automatic
3540 invocation of pxdb, and the aCC custom C++ ABI. This does not
3541 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3542 with aCC can still be debugged on an assembly level.
3544 MIPS ".pdr" sections
3546 A MIPS-specific format used to describe stack frame layout
3547 in debugging information.
3551 GDB could work with an older version of Guile to debug
3552 the interpreter and Scheme programs running in it.
3554 set mips stack-arg-size
3555 set mips saved-gpreg-size
3557 Use "set mips abi" to control parameter passing for MIPS.
3559 *** Changes in GDB 6.6
3564 Cell Broadband Engine SPU spu-elf
3566 * GDB can now be configured as a cross-debugger targeting native Windows
3567 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3568 running on a Windows system over TCP/IP to debug Windows programs.
3570 * The GDB remote stub, gdbserver, has been updated to support Windows and
3571 Cygwin debugging. Both single-threaded and multi-threaded programs are
3574 * The "set trust-readonly-sections" command works again. This command was
3575 broken in GDB 6.3, 6.4, and 6.5.
3577 * The "load" command now supports writing to flash memory, if the remote
3578 stub provides the required support.
3580 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3581 longer requires symbolic debug information (e.g. DWARF-2).
3586 unset substitute-path
3587 show substitute-path
3588 Manage a list of substitution rules that GDB uses to rewrite the name
3589 of the directories where the sources are located. This can be useful
3590 for instance when the sources were moved to a different location
3591 between compilation and debugging.
3595 Print each CLI command as it is executed. Each command is prefixed with
3596 a number of `+' symbols representing the nesting depth.
3597 The source command now has a `-v' option to enable the same feature.
3601 The ARM Demon monitor support (RDP protocol, "target rdp").
3603 Kernel Object Display, an embedded debugging feature which only worked with
3604 an obsolete version of Cisco IOS.
3606 The 'set download-write-size' and 'show download-write-size' commands.
3608 * New remote packets
3611 Tell a stub about GDB client features, and request remote target features.
3612 The first feature implemented is PacketSize, which allows the target to
3613 specify the size of packets it can handle - to minimize the number of
3614 packets required and improve performance when connected to a remote
3618 Fetch an OS auxilliary vector from the remote stub. This packet is a
3619 more efficient replacement for qPart:auxv:read.
3621 qXfer:memory-map:read:
3622 Fetch a memory map from the remote stub, including information about
3623 RAM, ROM, and flash memory devices.
3628 Erase and program a flash memory device.
3630 * Removed remote packets
3633 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3634 used it, and only gdbserver implemented it.
3636 *** Changes in GDB 6.5
3640 Renesas M32C/M16C m32c-elf
3642 Morpho Technologies ms1 ms1-elf
3646 init-if-undefined Initialize a convenience variable, but
3647 only if it doesn't already have a value.
3649 The following commands are presently only implemented for native GNU/Linux:
3651 checkpoint Save a snapshot of the program state.
3653 restart <n> Return the program state to a
3654 previously saved state.
3656 info checkpoints List currently saved checkpoints.
3658 delete-checkpoint <n> Delete a previously saved checkpoint.
3660 set|show detach-on-fork Tell gdb whether to detach from a newly
3661 forked process, or to keep debugging it.
3663 info forks List forks of the user program that
3664 are available to be debugged.
3666 fork <n> Switch to debugging one of several
3667 forks of the user program that are
3668 available to be debugged.
3670 delete-fork <n> Delete a fork from the list of forks
3671 that are available to be debugged (and
3672 kill the forked process).
3674 detach-fork <n> Delete a fork from the list of forks
3675 that are available to be debugged (and
3676 allow the process to continue).
3680 Morpho Technologies ms2 ms1-elf
3682 * Improved Windows host support
3684 GDB now builds as a cross debugger hosted on i686-mingw32, including
3685 native console support, and remote communications using either
3686 network sockets or serial ports.
3688 * Improved Modula-2 language support
3690 GDB can now print most types in the Modula-2 syntax. This includes:
3691 basic types, set types, record types, enumerated types, range types,
3692 pointer types and ARRAY types. Procedure var parameters are correctly
3693 printed and hexadecimal addresses and character constants are also
3694 written in the Modula-2 syntax. Best results can be obtained by using
3695 GNU Modula-2 together with the -gdwarf-2 command line option.
3699 The ARM rdi-share module.
3701 The Netware NLM debug server.
3703 *** Changes in GDB 6.4
3705 * New native configurations
3707 OpenBSD/arm arm*-*-openbsd*
3708 OpenBSD/mips64 mips64-*-openbsd*
3712 Morpho Technologies ms1 ms1-elf
3714 * New command line options
3716 --batch-silent As for --batch, but totally silent.
3717 --return-child-result The debugger will exist with the same value
3718 the child (debugged) program exited with.
3719 --eval-command COMMAND, -ex COMMAND
3720 Execute a single GDB CLI command. This may be
3721 specified multiple times and in conjunction
3722 with the --command (-x) option.
3724 * Deprecated commands removed
3726 The following commands, that were deprecated in 2000, have been
3730 set|show arm disassembly-flavor set|show arm disassembler
3731 othernames set arm disassembler
3732 set|show remotedebug set|show debug remote
3733 set|show archdebug set|show debug arch
3734 set|show eventdebug set|show debug event
3737 * New BSD user-level threads support
3739 It is now possible to debug programs using the user-level threads
3740 library on OpenBSD and FreeBSD. Currently supported (target)
3743 FreeBSD/amd64 x86_64-*-freebsd*
3744 FreeBSD/i386 i386-*-freebsd*
3745 OpenBSD/i386 i386-*-openbsd*
3747 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3748 are not yet supported.
3750 * New support for Matsushita MN10300 w/sim added
3751 (Work in progress). mn10300-elf.
3753 * REMOVED configurations and files
3755 VxWorks and the XDR protocol *-*-vxworks
3756 Motorola MCORE mcore-*-*
3757 National Semiconductor NS32000 ns32k-*-*
3759 * New "set print array-indexes" command
3761 After turning this setting "on", GDB prints the index of each element
3762 when displaying arrays. The default is "off" to preserve the previous
3765 * VAX floating point support
3767 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3769 * User-defined command support
3771 In addition to using $arg0..$arg9 for argument passing, it is now possible
3772 to use $argc to determine now many arguments have been passed. See the
3773 section on user-defined commands in the user manual for more information.
3775 *** Changes in GDB 6.3:
3777 * New command line option
3779 GDB now accepts -l followed by a number to set the timeout for remote
3782 * GDB works with GCC -feliminate-dwarf2-dups
3784 GDB now supports a more compact representation of DWARF-2 debug
3785 information using DW_FORM_ref_addr references. These are produced
3786 by GCC with the option -feliminate-dwarf2-dups and also by some
3787 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3788 to use -feliminate-dwarf2-dups.
3790 * Internationalization
3792 When supported by the host system, GDB will be built with
3793 internationalization (libintl). The task of marking up the sources is
3794 continued, we're looking forward to our first translation.
3798 Initial support for debugging programs compiled with the GNAT
3799 implementation of the Ada programming language has been integrated
3800 into GDB. In this release, support is limited to expression evaluation.
3802 * New native configurations
3804 GNU/Linux/m32r m32r-*-linux-gnu
3808 GDB's remote protocol now includes support for the 'p' packet. This
3809 packet is used to fetch individual registers from a remote inferior.
3811 * END-OF-LIFE registers[] compatibility module
3813 GDB's internal register infrastructure has been completely rewritten.
3814 The new infrastructure making possible the implementation of key new
3815 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3818 GDB 6.3 will be the last release to include the the registers[]
3819 compatibility module that allowed out-of-date configurations to
3820 continue to work. This change directly impacts the following
3830 powerpc bdm protocol
3832 Unless there is activity to revive these configurations, they will be
3833 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3835 * OBSOLETE configurations and files
3837 Configurations that have been declared obsolete in this release have
3838 been commented out. Unless there is activity to revive these
3839 configurations, the next release of GDB will have their sources
3840 permanently REMOVED.
3849 *** Changes in GDB 6.2.1:
3851 * MIPS `break main; run' gave an heuristic-fence-post warning
3853 When attempting to run even a simple program, a warning about
3854 heuristic-fence-post being hit would be reported. This problem has
3857 * MIPS IRIX 'long double' crashed GDB
3859 When examining a long double variable, GDB would get a segmentation
3860 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3861 IRIX long double values).
3865 A bug in the VAX stack code was causing problems with the "next"
3866 command. This problem has been fixed.
3868 *** Changes in GDB 6.2:
3870 * Fix for ``many threads''
3872 On GNU/Linux systems that use the NPTL threads library, a program
3873 rapidly creating and deleting threads would confuse GDB leading to the
3876 ptrace: No such process.
3877 thread_db_get_info: cannot get thread info: generic error
3879 This problem has been fixed.
3881 * "-async" and "-noasync" options removed.
3883 Support for the broken "-noasync" option has been removed (it caused
3886 * New ``start'' command.
3888 This command runs the program until the begining of the main procedure.
3890 * New BSD Kernel Data Access Library (libkvm) interface
3892 Using ``target kvm'' it is now possible to debug kernel core dumps and
3893 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3894 platforms. Currently supported (native-only) configurations are:
3896 FreeBSD/amd64 x86_64-*-freebsd*
3897 FreeBSD/i386 i?86-*-freebsd*
3898 NetBSD/i386 i?86-*-netbsd*
3899 NetBSD/m68k m68*-*-netbsd*
3900 NetBSD/sparc sparc-*-netbsd*
3901 OpenBSD/amd64 x86_64-*-openbsd*
3902 OpenBSD/i386 i?86-*-openbsd*
3903 OpenBSD/m68k m68*-openbsd*
3904 OpenBSD/sparc sparc-*-openbsd*
3906 * Signal trampoline code overhauled
3908 Many generic problems with GDB's signal handling code have been fixed.
3909 These include: backtraces through non-contiguous stacks; recognition
3910 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3911 call; backtrace through a signal trampoline; step into and out of
3912 signal handlers; and single-stepping in the signal trampoline.
3914 Please note that kernel bugs are a limiting factor here. These
3915 features have been shown to work on an s390 GNU/Linux system that
3916 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3918 * Cygwin support for DWARF 2 added.
3920 * New native configurations
3922 GNU/Linux/hppa hppa*-*-linux*
3923 OpenBSD/hppa hppa*-*-openbsd*
3924 OpenBSD/m68k m68*-*-openbsd*
3925 OpenBSD/m88k m88*-*-openbsd*
3926 OpenBSD/powerpc powerpc-*-openbsd*
3927 NetBSD/vax vax-*-netbsd*
3928 OpenBSD/vax vax-*-openbsd*
3930 * END-OF-LIFE frame compatibility module
3932 GDB's internal frame infrastructure has been completely rewritten.
3933 The new infrastructure making it possible to support key new features
3934 including DWARF 2 Call Frame Information. To aid in the task of
3935 migrating old configurations to this new infrastructure, a
3936 compatibility module, that allowed old configurations to continue to
3937 work, was also included.
3939 GDB 6.2 will be the last release to include this frame compatibility
3940 module. This change directly impacts the following configurations:
3950 Unless there is activity to revive these configurations, they will be
3951 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3953 * REMOVED configurations and files
3955 Sun 3, running SunOS 3 m68*-*-sunos3*
3956 Sun 3, running SunOS 4 m68*-*-sunos4*
3957 Sun 2, running SunOS 3 m68000-*-sunos3*
3958 Sun 2, running SunOS 4 m68000-*-sunos4*
3959 Motorola 680x0 running LynxOS m68*-*-lynxos*
3960 AT&T 3b1/Unix pc m68*-att-*
3961 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3962 decstation mips-dec-* mips-little-*
3963 riscos mips-*-riscos* mips-*-sysv*
3964 sonymips mips-sony-*
3965 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3967 *** Changes in GDB 6.1.1:
3969 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3971 The TUI (Text-mode User Interface) is now built as part of a default
3972 GDB configuration. It is enabled by either selecting the TUI with the
3973 command line option "-i=tui" or by running the separate "gdbtui"
3974 program. For more information on the TUI, see the manual "Debugging
3977 * Pending breakpoint support (also included in GDB 6.1)
3979 Support has been added to allow you to specify breakpoints in shared
3980 libraries that have not yet been loaded. If a breakpoint location
3981 cannot be found, and the "breakpoint pending" option is set to auto,
3982 GDB queries you if you wish to make the breakpoint pending on a future
3983 shared-library load. If and when GDB resolves the breakpoint symbol,
3984 the pending breakpoint is removed as one or more regular breakpoints
3987 Pending breakpoints are very useful for GCJ Java debugging.
3989 * Fixed ISO-C build problems
3991 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3992 non ISO-C code that stopped them being built using a more strict ISO-C
3993 compiler (e.g., IBM's C compiler).
3995 * Fixed build problem on IRIX 5
3997 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3998 wasn't able to compile compile on an IRIX 5 system.
4000 * Added execute permission to gdb/gdbserver/configure
4002 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4003 permission. This bug would cause configure to fail on a number of
4004 systems (Solaris, IRIX). Ref: server/519.
4006 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4008 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4009 has been updated to use constant array sizes.
4011 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4013 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4014 its generated DWARF Call Frame Info. This encoding was causing GDB to
4015 panic, that panic has been fixed. Ref: gdb/1628.
4017 * Fixed a problem when examining parameters in shared library code.
4019 When examining parameters in optimized shared library code generated
4020 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4021 not available''. GDB now correctly displays the variable's value.
4023 *** Changes in GDB 6.1:
4025 * Removed --with-mmalloc
4027 Support for the mmalloc memory manager has been removed, as it
4028 conflicted with the internal gdb byte cache.
4030 * Changes in AMD64 configurations
4032 The AMD64 target now includes the %cs and %ss registers. As a result
4033 the AMD64 remote protocol has changed; this affects the floating-point
4034 and SSE registers. If you rely on those registers for your debugging,
4035 you should upgrade gdbserver on the remote side.
4037 * Revised SPARC target
4039 The SPARC target has been completely revised, incorporating the
4040 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4041 support for LynxOS and SunOS 4 has been dropped. Calling functions
4042 from within GDB on operating systems with a non-executable stack
4043 (Solaris, OpenBSD) now works.
4047 GDB has a new C++ demangler which does a better job on the mangled
4048 names generated by current versions of g++. It also runs faster, so
4049 with this and other changes gdb should now start faster on large C++
4052 * DWARF 2 Location Expressions
4054 GDB support for location expressions has been extended to support function
4055 arguments and frame bases. Older versions of GDB could crash when they
4058 * C++ nested types and namespaces
4060 GDB's support for nested types and namespaces in C++ has been
4061 improved, especially if you use the DWARF 2 debugging format. (This
4062 is the default for recent versions of GCC on most platforms.)
4063 Specifically, if you have a class "Inner" defined within a class or
4064 namespace "Outer", then GDB realizes that the class's name is
4065 "Outer::Inner", not simply "Inner". This should greatly reduce the
4066 frequency of complaints about not finding RTTI symbols. In addition,
4067 if you are stopped at inside of a function defined within a namespace,
4068 GDB modifies its name lookup accordingly.
4070 * New native configurations
4072 NetBSD/amd64 x86_64-*-netbsd*
4073 OpenBSD/amd64 x86_64-*-openbsd*
4074 OpenBSD/alpha alpha*-*-openbsd*
4075 OpenBSD/sparc sparc-*-openbsd*
4076 OpenBSD/sparc64 sparc64-*-openbsd*
4078 * New debugging protocols
4080 M32R with SDI protocol m32r-*-elf*
4082 * "set prompt-escape-char" command deleted.
4084 The command "set prompt-escape-char" has been deleted. This command,
4085 and its very obscure effet on GDB's prompt, was never documented,
4086 tested, nor mentioned in the NEWS file.
4088 * OBSOLETE configurations and files
4090 Configurations that have been declared obsolete in this release have
4091 been commented out. Unless there is activity to revive these
4092 configurations, the next release of GDB will have their sources
4093 permanently REMOVED.
4095 Sun 3, running SunOS 3 m68*-*-sunos3*
4096 Sun 3, running SunOS 4 m68*-*-sunos4*
4097 Sun 2, running SunOS 3 m68000-*-sunos3*
4098 Sun 2, running SunOS 4 m68000-*-sunos4*
4099 Motorola 680x0 running LynxOS m68*-*-lynxos*
4100 AT&T 3b1/Unix pc m68*-att-*
4101 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4102 decstation mips-dec-* mips-little-*
4103 riscos mips-*-riscos* mips-*-sysv*
4104 sonymips mips-sony-*
4105 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4107 * REMOVED configurations and files
4109 SGI Irix-4.x mips-sgi-irix4 or iris4
4110 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4111 Z8000 simulator z8k-zilog-none or z8ksim
4112 Matsushita MN10200 w/simulator mn10200-*-*
4113 H8/500 simulator h8500-hitachi-hms or h8500hms
4114 HP/PA running BSD hppa*-*-bsd*
4115 HP/PA running OSF/1 hppa*-*-osf*
4116 HP/PA Pro target hppa*-*-pro*
4117 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4118 386BSD i[3456]86-*-bsd*
4119 Sequent family i[3456]86-sequent-sysv4*
4120 i[3456]86-sequent-sysv*
4121 i[3456]86-sequent-bsd*
4122 SPARC running LynxOS sparc-*-lynxos*
4123 SPARC running SunOS 4 sparc-*-sunos4*
4124 Tsqware Sparclet sparclet-*-*
4125 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4127 *** Changes in GDB 6.0:
4131 Support for debugging the Objective-C programming language has been
4132 integrated into GDB.
4134 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4136 DWARF 2's Call Frame Information makes available compiler generated
4137 information that more exactly describes the program's run-time stack.
4138 By using this information, GDB is able to provide more robust stack
4141 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4142 have been updated to use a new backtrace mechanism which includes
4143 DWARF 2 CFI support.
4147 GDB's remote protocol has been extended to include support for hosted
4148 file I/O (where the remote target uses GDB's file system). See GDB's
4149 remote protocol documentation for details.
4151 * All targets using the new architecture framework.
4153 All of GDB's targets have been updated to use the new internal
4154 architecture framework. The way is now open for future GDB releases
4155 to include cross-architecture native debugging support (i386 on amd64,
4158 * GNU/Linux's Thread Local Storage (TLS)
4160 GDB now includes support for for the GNU/Linux implementation of
4161 per-thread variables.
4163 * GNU/Linux's Native POSIX Thread Library (NPTL)
4165 GDB's thread code has been updated to work with either the new
4166 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4168 * Separate debug info.
4170 GDB, in conjunction with BINUTILS, now supports a mechanism for
4171 automatically loading debug information from a separate file. Instead
4172 of shipping full debug and non-debug versions of system libraries,
4173 system integrators can now instead ship just the stripped libraries
4174 and optional debug files.
4176 * DWARF 2 Location Expressions
4178 DWARF 2 Location Expressions allow the compiler to more completely
4179 describe the location of variables (even in optimized code) to the
4182 GDB now includes preliminary support for location expressions (support
4183 for DW_OP_piece is still missing).
4187 A number of long standing bugs that caused GDB to die while starting a
4188 Java application have been fixed. GDB's Java support is now
4189 considered "useable".
4191 * GNU/Linux support for fork, vfork, and exec.
4193 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4194 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4197 * GDB supports logging output to a file
4199 There are two new commands, "set logging" and "show logging", which can be
4200 used to capture GDB's output to a file.
4202 * The meaning of "detach" has changed for gdbserver
4204 The "detach" command will now resume the application, as documented. To
4205 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4208 * d10v, m68hc11 `regs' command deprecated
4210 The `info registers' command has been updated so that it displays the
4211 registers using a format identical to the old `regs' command.
4215 A new command, "maint set profile on/off", has been added. This command can
4216 be used to enable or disable profiling while running GDB, to profile a
4217 session or a set of commands. In addition there is a new configure switch,
4218 "--enable-profiling", which will cause GDB to be compiled with profiling
4219 data, for more informative profiling results.
4221 * Default MI syntax changed to "mi2".
4223 The default MI (machine interface) syntax, enabled by the command line
4224 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4225 "mi1", can be enabled by specifying the option "-i=mi1".
4227 Support for the original "mi0" syntax (included in GDB 5.0) has been
4230 Fix for gdb/192: removed extraneous space when displaying frame level.
4231 Fix for gdb/672: update changelist is now output in mi list format.
4232 Fix for gdb/702: a -var-assign that updates the value now shows up
4233 in a subsequent -var-update.
4235 * New native configurations.
4237 FreeBSD/amd64 x86_64-*-freebsd*
4239 * Multi-arched targets.
4241 HP/PA HPUX11 hppa*-*-hpux*
4242 Renesas M32R/D w/simulator m32r-*-elf*
4244 * OBSOLETE configurations and files
4246 Configurations that have been declared obsolete in this release have
4247 been commented out. Unless there is activity to revive these
4248 configurations, the next release of GDB will have their sources
4249 permanently REMOVED.
4251 Z8000 simulator z8k-zilog-none or z8ksim
4252 Matsushita MN10200 w/simulator mn10200-*-*
4253 H8/500 simulator h8500-hitachi-hms or h8500hms
4254 HP/PA running BSD hppa*-*-bsd*
4255 HP/PA running OSF/1 hppa*-*-osf*
4256 HP/PA Pro target hppa*-*-pro*
4257 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4258 Sequent family i[3456]86-sequent-sysv4*
4259 i[3456]86-sequent-sysv*
4260 i[3456]86-sequent-bsd*
4261 Tsqware Sparclet sparclet-*-*
4262 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4264 * REMOVED configurations and files
4267 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4268 IBM AIX PS/2 i[3456]86-*-aix
4269 i386 running Mach 3.0 i[3456]86-*-mach3*
4270 i386 running Mach i[3456]86-*-mach*
4271 i386 running OSF/1 i[3456]86-*osf1mk*
4272 HP/Apollo 68k Family m68*-apollo*-sysv*,
4274 m68*-hp-bsd*, m68*-hp-hpux*
4275 Argonaut Risc Chip (ARC) arc-*-*
4276 Mitsubishi D30V d30v-*-*
4277 Fujitsu FR30 fr30-*-elf*
4278 OS/9000 i[34]86-*-os9k
4279 I960 with MON960 i960-*-coff
4281 * MIPS $fp behavior changed
4283 The convenience variable $fp, for the MIPS, now consistently returns
4284 the address of the current frame's base. Previously, depending on the
4285 context, $fp could refer to either $sp or the current frame's base
4286 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4287 The GNU Source-Level Debugger''.
4289 *** Changes in GDB 5.3:
4291 * GNU/Linux shared library multi-threaded performance improved.
4293 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4294 `/proc', in preference to `ptrace' for memory reads. This may result
4295 in an improvement in the start-up time of multi-threaded, shared
4296 library applications when run under GDB. One GDB user writes: ``loads
4297 shared libs like mad''.
4299 * ``gdbserver'' now supports multi-threaded applications on some targets
4301 Support for debugging multi-threaded applications which use
4302 the GNU/Linux LinuxThreads package has been added for
4303 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4304 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4306 * GDB now supports C/C++ preprocessor macros.
4308 GDB now expands preprocessor macro invocations in C/C++ expressions,
4309 and provides various commands for showing macro definitions and how
4312 The new command `macro expand EXPRESSION' expands any macro
4313 invocations in expression, and shows the result.
4315 The new command `show macro MACRO-NAME' shows the definition of the
4316 macro named MACRO-NAME, and where it was defined.
4318 Most compilers don't include information about macros in the debugging
4319 information by default. In GCC 3.1, for example, you need to compile
4320 your program with the options `-gdwarf-2 -g3'. If the macro
4321 information is present in the executable, GDB will read it.
4323 * Multi-arched targets.
4325 DEC Alpha (partial) alpha*-*-*
4326 DEC VAX (partial) vax-*-*
4328 National Semiconductor NS32000 (partial) ns32k-*-*
4329 Motorola 68000 (partial) m68k-*-*
4330 Motorola MCORE mcore-*-*
4334 Fujitsu FRV architecture added by Red Hat frv*-*-*
4337 * New native configurations
4339 Alpha NetBSD alpha*-*-netbsd*
4340 SH NetBSD sh*-*-netbsdelf*
4341 MIPS NetBSD mips*-*-netbsd*
4342 UltraSPARC NetBSD sparc64-*-netbsd*
4344 * OBSOLETE configurations and files
4346 Configurations that have been declared obsolete in this release have
4347 been commented out. Unless there is activity to revive these
4348 configurations, the next release of GDB will have their sources
4349 permanently REMOVED.
4351 Mitsubishi D30V d30v-*-*
4352 OS/9000 i[34]86-*-os9k
4353 IBM AIX PS/2 i[3456]86-*-aix
4354 Fujitsu FR30 fr30-*-elf*
4355 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4356 Argonaut Risc Chip (ARC) arc-*-*
4357 i386 running Mach 3.0 i[3456]86-*-mach3*
4358 i386 running Mach i[3456]86-*-mach*
4359 i386 running OSF/1 i[3456]86-*osf1mk*
4360 HP/Apollo 68k Family m68*-apollo*-sysv*,
4362 m68*-hp-bsd*, m68*-hp-hpux*
4363 I960 with MON960 i960-*-coff
4365 * OBSOLETE languages
4367 CHILL, a Pascal like language used by telecommunications companies.
4369 * REMOVED configurations and files
4371 AMD 29k family via UDI a29k-amd-udi, udi29k
4372 A29K VxWorks a29k-*-vxworks
4373 AMD 29000 embedded, using EBMON a29k-none-none
4374 AMD 29000 embedded with COFF a29k-none-coff
4375 AMD 29000 embedded with a.out a29k-none-aout
4377 testsuite/gdb.hp/gdb.threads-hp/ directory
4379 * New command "set max-user-call-depth <nnn>"
4381 This command allows the user to limit the call depth of user-defined
4382 commands. The default is 1024.
4384 * Changes in FreeBSD/i386 native debugging.
4386 Support for the "generate-core-file" has been added.
4388 * New commands "dump", "append", and "restore".
4390 These commands allow data to be copied from target memory
4391 to a bfd-format or binary file (dump and append), and back
4392 from a file into memory (restore).
4394 * Improved "next/step" support on multi-processor Alpha Tru64.
4396 The previous single-step mechanism could cause unpredictable problems,
4397 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4398 of a software single-step mechanism prevents this.
4400 *** Changes in GDB 5.2.1:
4408 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4409 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4410 Fix, by Joel Brobecker imported from mainline.
4412 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4413 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4414 Fix, by Fred Fish, imported from mainline.
4416 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4417 Surprisingly enough, it works now.
4418 By Michal Ludvig, imported from mainline.
4420 i386 hardware watchpoint support:
4421 avoid misses on second run for some targets.
4422 By Pierre Muller, imported from mainline.
4424 *** Changes in GDB 5.2:
4426 * New command "set trust-readonly-sections on[off]".
4428 This command is a hint that tells gdb that read-only sections
4429 really are read-only (ie. that their contents will not change).
4430 In this mode, gdb will go to the object file rather than the
4431 target to read memory from read-only sections (such as ".text").
4432 This can be a significant performance improvement on some
4433 (notably embedded) targets.
4435 * New command "generate-core-file" (or "gcore").
4437 This new gdb command allows the user to drop a core file of the child
4438 process state at any time. So far it's been implemented only for
4439 GNU/Linux and Solaris, but should be relatively easily ported to other
4440 hosts. Argument is core file name (defaults to core.<pid>).
4442 * New command line option
4444 GDB now accepts --pid or -p followed by a process id.
4446 * Change in command line behavior -- corefiles vs. process ids.
4448 There is a subtle behavior in the way in which GDB handles
4449 command line arguments. The first non-flag argument is always
4450 a program to debug, but the second non-flag argument may either
4451 be a corefile or a process id. Previously, GDB would attempt to
4452 open the second argument as a corefile, and if that failed, would
4453 issue a superfluous error message and then attempt to attach it as
4454 a process. Now, if the second argument begins with a non-digit,
4455 it will be treated as a corefile. If it begins with a digit,
4456 GDB will attempt to attach it as a process, and if no such process
4457 is found, will then attempt to open it as a corefile.
4459 * Changes in ARM configurations.
4461 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4462 configuration is fully multi-arch.
4464 * New native configurations
4466 ARM NetBSD arm*-*-netbsd*
4467 x86 OpenBSD i[3456]86-*-openbsd*
4468 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4469 Sparc64 running FreeBSD sparc64-*-freebsd*
4473 Sanyo XStormy16 xstormy16-elf
4475 * OBSOLETE configurations and files
4477 Configurations that have been declared obsolete in this release have
4478 been commented out. Unless there is activity to revive these
4479 configurations, the next release of GDB will have their sources
4480 permanently REMOVED.
4482 AMD 29k family via UDI a29k-amd-udi, udi29k
4483 A29K VxWorks a29k-*-vxworks
4484 AMD 29000 embedded, using EBMON a29k-none-none
4485 AMD 29000 embedded with COFF a29k-none-coff
4486 AMD 29000 embedded with a.out a29k-none-aout
4488 testsuite/gdb.hp/gdb.threads-hp/ directory
4490 * REMOVED configurations and files
4492 TI TMS320C80 tic80-*-*
4494 PowerPC Solaris powerpcle-*-solaris*
4495 PowerPC Windows NT powerpcle-*-cygwin32
4496 PowerPC Netware powerpc-*-netware*
4497 Harris/CXUX m88k m88*-harris-cxux*
4498 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4499 ns32k-utek-sysv* ns32k-utek-*
4500 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4501 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4502 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4503 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4504 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4506 * Changes to command line processing
4508 The new `--args' feature can be used to specify command-line arguments
4509 for the inferior from gdb's command line.
4511 * Changes to key bindings
4513 There is a new `operate-and-get-next' function bound to `C-o'.
4515 *** Changes in GDB 5.1.1
4517 Fix compile problem on DJGPP.
4519 Fix a problem with floating-point registers on the i386 being
4522 Fix to stop GDB crashing on .debug_str debug info.
4524 Numerous documentation fixes.
4526 Numerous testsuite fixes.
4528 *** Changes in GDB 5.1:
4530 * New native configurations
4532 Alpha FreeBSD alpha*-*-freebsd*
4533 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4534 MIPS GNU/Linux mips*-*-linux*
4535 MIPS SGI Irix 6.x mips*-sgi-irix6*
4536 ia64 AIX ia64-*-aix*
4537 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4541 Motorola 68HC11 and 68HC12 m68hc11-elf
4543 UltraSparc running GNU/Linux sparc64-*-linux*
4545 * OBSOLETE configurations and files
4547 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4548 Harris/CXUX m88k m88*-harris-cxux*
4549 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4550 ns32k-utek-sysv* ns32k-utek-*
4551 TI TMS320C80 tic80-*-*
4553 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4554 PowerPC Solaris powerpcle-*-solaris*
4555 PowerPC Windows NT powerpcle-*-cygwin32
4556 PowerPC Netware powerpc-*-netware*
4557 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4558 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4559 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4560 Apple Macintosh (MPW) host N/A
4562 stuff.c (Program to stuff files into a specially prepared space in kdb)
4563 kdb-start.c (Main loop for the standalone kernel debugger)
4565 Configurations that have been declared obsolete in this release have
4566 been commented out. Unless there is activity to revive these
4567 configurations, the next release of GDB will have their sources
4568 permanently REMOVED.
4570 * REMOVED configurations and files
4572 Altos 3068 m68*-altos-*
4573 Convex c1-*-*, c2-*-*
4575 ARM RISCix arm-*-* (as host)
4579 * GDB has been converted to ISO C.
4581 GDB's source code has been converted to ISO C. In particular, the
4582 sources are fully protoized, and rely on standard headers being
4587 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4589 * The MI enabled by default.
4591 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4592 revised and enabled by default. Packages which use GDB as a debugging
4593 engine behind a UI or another front end are encouraged to switch to
4594 using the GDB/MI interface, instead of the old annotations interface
4595 which is now deprecated.
4597 * Support for debugging Pascal programs.
4599 GDB now includes support for debugging Pascal programs. The following
4600 main features are supported:
4602 - Pascal-specific data types such as sets;
4604 - automatic recognition of Pascal sources based on file-name
4607 - Pascal-style display of data types, variables, and functions;
4609 - a Pascal expression parser.
4611 However, some important features are not yet supported.
4613 - Pascal string operations are not supported at all;
4615 - there are some problems with boolean types;
4617 - Pascal type hexadecimal constants are not supported
4618 because they conflict with the internal variables format;
4620 - support for Pascal objects and classes is not full yet;
4622 - unlike Pascal, GDB is case-sensitive for symbol names.
4624 * Changes in completion.
4626 Commands such as `shell', `run' and `set args', which pass arguments
4627 to inferior programs, now complete on file names, similar to what
4628 users expect at the shell prompt.
4630 Commands which accept locations, such as `disassemble', `print',
4631 `breakpoint', `until', etc. now complete on filenames as well as
4632 program symbols. Thus, if you type "break foob TAB", and the source
4633 files linked into the programs include `foobar.c', that file name will
4634 be one of the candidates for completion. However, file names are not
4635 considered for completion after you typed a colon that delimits a file
4636 name from a name of a function in that file, as in "break foo.c:bar".
4638 `set demangle-style' completes on available demangling styles.
4640 * New platform-independent commands:
4642 It is now possible to define a post-hook for a command as well as a
4643 hook that runs before the command. For more details, see the
4644 documentation of `hookpost' in the GDB manual.
4646 * Changes in GNU/Linux native debugging.
4648 Support for debugging multi-threaded programs has been completely
4649 revised for all platforms except m68k and sparc. You can now debug as
4650 many threads as your system allows you to have.
4652 Attach/detach is supported for multi-threaded programs.
4654 Support for SSE registers was added for x86. This doesn't work for
4655 multi-threaded programs though.
4657 * Changes in MIPS configurations.
4659 Multi-arch support is enabled for all MIPS configurations.
4661 GDB can now be built as native debugger on SGI Irix 6.x systems for
4662 debugging n32 executables. (Debugging 64-bit executables is not yet
4665 * Unified support for hardware watchpoints in all x86 configurations.
4667 Most (if not all) native x86 configurations support hardware-assisted
4668 breakpoints and watchpoints in a unified manner. This support
4669 implements debug register sharing between watchpoints, which allows to
4670 put a virtually infinite number of watchpoints on the same address,
4671 and also supports watching regions up to 16 bytes with several debug
4674 The new maintenance command `maintenance show-debug-regs' toggles
4675 debugging print-outs in functions that insert, remove, and test
4676 watchpoints and hardware breakpoints.
4678 * Changes in the DJGPP native configuration.
4680 New command ``info dos sysinfo'' displays assorted information about
4681 the CPU, OS, memory, and DPMI server.
4683 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4684 display information about segment descriptors stored in GDT, LDT, and
4687 New commands ``info dos pde'' and ``info dos pte'' display entries
4688 from Page Directory and Page Tables (for now works with CWSDPMI only).
4689 New command ``info dos address-pte'' displays the Page Table entry for
4690 a given linear address.
4692 GDB can now pass command lines longer than 126 characters to the
4693 program being debugged (requires an update to the libdbg.a library
4694 which is part of the DJGPP development kit).
4696 DWARF2 debug info is now supported.
4698 It is now possible to `step' and `next' through calls to `longjmp'.
4700 * Changes in documentation.
4702 All GDB documentation was converted to GFDL, the GNU Free
4703 Documentation License.
4705 Tracepoints-related commands are now fully documented in the GDB
4708 TUI, the Text-mode User Interface, is now documented in the manual.
4710 Tracepoints-related commands are now fully documented in the GDB
4713 The "GDB Internals" manual now has an index. It also includes
4714 documentation of `ui_out' functions, GDB coding standards, x86
4715 hardware watchpoints, and memory region attributes.
4717 * GDB's version number moved to ``version.in''
4719 The Makefile variable VERSION has been replaced by the file
4720 ``version.in''. People creating GDB distributions should update the
4721 contents of this file.
4725 GUD support is now a standard part of the EMACS distribution.
4727 *** Changes in GDB 5.0:
4729 * Improved support for debugging FP programs on x86 targets
4731 Unified and much-improved support for debugging floating-point
4732 programs on all x86 targets. In particular, ``info float'' now
4733 displays the FP registers in the same format on all x86 targets, with
4734 greater level of detail.
4736 * Improvements and bugfixes in hardware-assisted watchpoints
4738 It is now possible to watch array elements, struct members, and
4739 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4740 on x86 targets no longer erroneously trigger when the address is
4743 * Improvements in the native DJGPP version of GDB
4745 The distribution now includes all the scripts and auxiliary files
4746 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4747 machines ``out of the box''.
4749 The DJGPP version can now debug programs that use signals. It is
4750 possible to catch signals that happened in the debuggee, deliver
4751 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4752 would kill the program being debugged.) Programs that hook hardware
4753 interrupts (keyboard, timer, etc.) can also be debugged.
4755 It is now possible to debug DJGPP programs that redirect their
4756 standard handles or switch them to raw (as opposed to cooked) mode, or
4757 even close them. The command ``run < foo > bar'' works as expected,
4758 and ``info terminal'' reports useful information about the debuggee's
4759 terminal, including raw/cooked mode, redirection, etc.
4761 The DJGPP version now uses termios functions for console I/O, which
4762 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4765 DOS-style file names with drive letters are now fully supported by
4768 It is now possible to debug DJGPP programs that switch their working
4769 directory. It is also possible to rerun the debuggee any number of
4770 times without restarting GDB; thus, you can use the same setup,
4771 breakpoints, etc. for many debugging sessions.
4773 * New native configurations
4775 ARM GNU/Linux arm*-*-linux*
4776 PowerPC GNU/Linux powerpc-*-linux*
4780 Motorola MCore mcore-*-*
4781 x86 VxWorks i[3456]86-*-vxworks*
4782 PowerPC VxWorks powerpc-*-vxworks*
4783 TI TMS320C80 tic80-*-*
4785 * OBSOLETE configurations
4787 Altos 3068 m68*-altos-*
4788 Convex c1-*-*, c2-*-*
4790 ARM RISCix arm-*-* (as host)
4793 Configurations that have been declared obsolete will be commented out,
4794 but the code will be left in place. If there is no activity to revive
4795 these configurations before the next release of GDB, the sources will
4796 be permanently REMOVED.
4798 * Gould support removed
4800 Support for the Gould PowerNode and NP1 has been removed.
4802 * New features for SVR4
4804 On SVR4 native platforms (such as Solaris), if you attach to a process
4805 without first loading a symbol file, GDB will now attempt to locate and
4806 load symbols from the running process's executable file.
4808 * Many C++ enhancements
4810 C++ support has been greatly improved. Overload resolution now works properly
4811 in almost all cases. RTTI support is on the way.
4813 * Remote targets can connect to a sub-program
4815 A popen(3) style serial-device has been added. This device starts a
4816 sub-process (such as a stand-alone simulator) and then communicates
4817 with that. The sub-program to run is specified using the syntax
4818 ``|<program> <args>'' vis:
4820 (gdb) set remotedebug 1
4821 (gdb) target extended-remote |mn10300-elf-sim program-args
4823 * MIPS 64 remote protocol
4825 A long standing bug in the mips64 remote protocol where by GDB
4826 expected certain 32 bit registers (ex SR) to be transfered as 32
4827 instead of 64 bits has been fixed.
4829 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4830 added to provide backward compatibility with older versions of GDB.
4832 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4834 The command ``set remotebinarydownload'' command has been replaced by
4835 ``set remote X-packet''. Other commands in ``set remote'' family
4836 include ``set remote P-packet''.
4838 * Breakpoint commands accept ranges.
4840 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4841 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4842 ``tracepoint passcount'' also accepts a range of tracepoints.
4844 * ``apropos'' command added.
4846 The ``apropos'' command searches through command names and
4847 documentation strings, printing out matches, making it much easier to
4848 try to find a command that does what you are looking for.
4852 A new machine oriented interface (MI) has been added to GDB. This
4853 interface is designed for debug environments running GDB as a separate
4854 process. This is part of the long term libGDB project. See the
4855 "GDB/MI" chapter of the GDB manual for further information. It can be
4856 enabled by configuring with:
4858 .../configure --enable-gdbmi
4860 *** Changes in GDB-4.18:
4862 * New native configurations
4864 HP-UX 10.20 hppa*-*-hpux10.20
4865 HP-UX 11.x hppa*-*-hpux11.0*
4866 M68K GNU/Linux m68*-*-linux*
4870 Fujitsu FR30 fr30-*-elf*
4871 Intel StrongARM strongarm-*-*
4872 Mitsubishi D30V d30v-*-*
4874 * OBSOLETE configurations
4876 Gould PowerNode, NP1 np1-*-*, pn-*-*
4878 Configurations that have been declared obsolete will be commented out,
4879 but the code will be left in place. If there is no activity to revive
4880 these configurations before the next release of GDB, the sources will
4881 be permanently REMOVED.
4885 As a compatibility experiment, GDB's source files buildsym.h and
4886 buildsym.c have been converted to pure standard C, no longer
4887 containing any K&R compatibility code. We believe that all systems in
4888 use today either come with a standard C compiler, or have a GCC port
4889 available. If this is not true, please report the affected
4890 configuration to bug-gdb@gnu.org immediately. See the README file for
4891 information about getting a standard C compiler if you don't have one
4896 GDB now uses readline 2.2.
4898 * set extension-language
4900 You can now control the mapping between filename extensions and source
4901 languages by using the `set extension-language' command. For instance,
4902 you can ask GDB to treat .c files as C++ by saying
4903 set extension-language .c c++
4904 The command `info extensions' lists all of the recognized extensions
4905 and their associated languages.
4907 * Setting processor type for PowerPC and RS/6000
4909 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4910 you can use the `set processor' command to specify what variant of the
4911 PowerPC family you are debugging. The command
4915 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4916 following PowerPC and RS6000 variants:
4918 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4919 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4921 403GC IBM PowerPC 403GC
4922 505 Motorola PowerPC 505
4923 860 Motorola PowerPC 860 or 850
4924 601 Motorola PowerPC 601
4925 602 Motorola PowerPC 602
4926 603 Motorola/IBM PowerPC 603 or 603e
4927 604 Motorola PowerPC 604 or 604e
4928 750 Motorola/IBM PowerPC 750 or 750
4930 At the moment, this command just tells GDB what to name the
4931 special-purpose processor registers. Since almost all the affected
4932 registers are inaccessible to user-level programs, this command is
4933 only useful for remote debugging in its present form.
4937 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4938 more extensive support for HP-UX. Added features include shared
4939 library support, kernel threads and hardware watchpoints for 11.00,
4940 support for HP's ANSI C and C++ compilers, and a compatibility mode
4941 for xdb and dbx commands.
4945 HP's donation includes the new concept of catchpoints, which is a
4946 generalization of the old catch command. On HP-UX, it is now possible
4947 to catch exec, fork, and vfork, as well as library loading.
4949 This means that the existing catch command has changed; its first
4950 argument now specifies the type of catch to be set up. See the
4951 output of "help catch" for a list of catchpoint types.
4953 * Debugging across forks
4955 On HP-UX, you can choose which process to debug when a fork() happens
4960 HP has donated a curses-based terminal user interface (TUI). To get
4961 it, build with --enable-tui. Although this can be enabled for any
4962 configuration, at present it only works for native HP debugging.
4964 * GDB remote protocol additions
4966 A new protocol packet 'X' that writes binary data is now available.
4967 Default behavior is to try 'X', then drop back to 'M' if the stub
4968 fails to respond. The settable variable `remotebinarydownload'
4969 allows explicit control over the use of 'X'.
4971 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4972 full 64-bit address. The command
4974 set remoteaddresssize 32
4976 can be used to revert to the old behaviour. For existing remote stubs
4977 the change should not be noticed, as the additional address information
4980 In order to assist in debugging stubs, you may use the maintenance
4981 command `packet' to send any text string to the stub. For instance,
4983 maint packet heythere
4985 sends the packet "$heythere#<checksum>". Note that it is very easy to
4986 disrupt a debugging session by sending the wrong packet at the wrong
4989 The compare-sections command allows you to compare section data on the
4990 target to what is in the executable file without uploading or
4991 downloading, by comparing CRC checksums.
4993 * Tracing can collect general expressions
4995 You may now collect general expressions at tracepoints. This requires
4996 further additions to the target-side stub; see tracepoint.c and
4997 doc/agentexpr.texi for further details.
4999 * mask-address variable for Mips
5001 For Mips targets, you may control the zeroing of the upper 32 bits of
5002 a 64-bit address by entering `set mask-address on'. This is mainly
5003 of interest to users of embedded R4xxx and R5xxx processors.
5005 * Higher serial baud rates
5007 GDB's serial code now allows you to specify baud rates 57600, 115200,
5008 230400, and 460800 baud. (Note that your host system may not be able
5009 to achieve all of these rates.)
5013 The i960 configuration now includes an initial implementation of a
5014 builtin simulator, contributed by Jim Wilson.
5017 *** Changes in GDB-4.17:
5019 * New native configurations
5021 Alpha GNU/Linux alpha*-*-linux*
5022 Unixware 2.x i[3456]86-unixware2*
5023 Irix 6.x mips*-sgi-irix6*
5024 PowerPC GNU/Linux powerpc-*-linux*
5025 PowerPC Solaris powerpcle-*-solaris*
5026 Sparc GNU/Linux sparc-*-linux*
5027 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5031 Argonaut Risc Chip (ARC) arc-*-*
5032 Hitachi H8/300S h8300*-*-*
5033 Matsushita MN10200 w/simulator mn10200-*-*
5034 Matsushita MN10300 w/simulator mn10300-*-*
5035 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5036 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5037 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5038 Mitsubishi D10V w/simulator d10v-*-*
5039 Mitsubishi M32R/D w/simulator m32r-*-elf*
5040 Tsqware Sparclet sparclet-*-*
5041 NEC V850 w/simulator v850-*-*
5043 * New debugging protocols
5045 ARM with RDI protocol arm*-*-*
5046 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5047 DDB and LSI variants of PMON protocol mips*-*-*
5048 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5049 PowerPC with SDS protocol powerpc{,le}-*-eabi
5050 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5054 All configurations can now understand and use the DWARF 2 debugging
5055 format. The choice is automatic, if the symbol file contains DWARF 2
5060 GDB now includes basic Java language support. This support is
5061 only useful with Java compilers that produce native machine code.
5063 * solib-absolute-prefix and solib-search-path
5065 For SunOS and SVR4 shared libraries, you may now set the prefix for
5066 loading absolute shared library symbol files, and the search path for
5067 locating non-absolute shared library symbol files.
5069 * Live range splitting
5071 GDB can now effectively debug code for which GCC has performed live
5072 range splitting as part of its optimization. See gdb/doc/LRS for
5073 more details on the expected format of the stabs information.
5077 GDB's support for the GNU Hurd, including thread debugging, has been
5078 updated to work with current versions of the Hurd.
5082 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5083 instruction set. ARM GDB automatically detects when Thumb
5084 instructions are in use, and adjusts disassembly and backtracing
5089 GDB's MIPS target configurations now handle the MIP16 16-bit
5094 GDB now includes support for overlays; if an executable has been
5095 linked such that multiple sections are based at the same address, GDB
5096 will decide which section to use for symbolic info. You can choose to
5097 control the decision manually, using overlay commands, or implement
5098 additional target-side support and use "overlay load-target" to bring
5099 in the overlay mapping. Do "help overlay" for more detail.
5103 The command "info symbol <address>" displays information about
5104 the symbol at the specified address.
5108 The standard remote protocol now includes an extension that allows
5109 asynchronous collection and display of trace data. This requires
5110 extensive support in the target-side debugging stub. Tracing mode
5111 includes a new interaction mode in GDB and new commands: see the
5112 file tracepoint.c for more details.
5116 Configurations for embedded MIPS now include a simulator contributed
5117 by Cygnus Solutions. The simulator supports the instruction sets
5118 of most MIPS variants.
5122 Sparc configurations may now include the ERC32 simulator contributed
5123 by the European Space Agency. The simulator is not built into
5124 Sparc targets by default; configure with --enable-sim to include it.
5128 For target configurations that may include multiple variants of a
5129 basic architecture (such as MIPS and SH), you may now set the
5130 architecture explicitly. "set arch" sets, "info arch" lists
5131 the possible architectures.
5133 *** Changes in GDB-4.16:
5135 * New native configurations
5137 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5138 M68K NetBSD m68k-*-netbsd*
5139 PowerPC AIX 4.x powerpc-*-aix*
5140 PowerPC MacOS powerpc-*-macos*
5141 PowerPC Windows NT powerpcle-*-cygwin32
5142 RS/6000 AIX 4.x rs6000-*-aix4*
5146 ARM with RDP protocol arm-*-*
5147 I960 with MON960 i960-*-coff
5148 MIPS VxWorks mips*-*-vxworks*
5149 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5150 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5152 Matra Sparclet sparclet-*-*
5156 The powerpc-eabi configuration now includes the PSIM simulator,
5157 contributed by Andrew Cagney, with assistance from Mike Meissner.
5158 PSIM is a very elaborate model of the PowerPC, including not only
5159 basic instruction set execution, but also details of execution unit
5160 performance and I/O hardware. See sim/ppc/README for more details.
5164 GDB now works with Solaris 2.5.
5166 * Windows 95/NT native
5168 GDB will now work as a native debugger on Windows 95 and Windows NT.
5169 To build it from source, you must use the "gnu-win32" environment,
5170 which uses a DLL to emulate enough of Unix to run the GNU tools.
5171 Further information, binaries, and sources are available at
5172 ftp.cygnus.com, under pub/gnu-win32.
5174 * dont-repeat command
5176 If a user-defined command includes the command `dont-repeat', then the
5177 command will not be repeated if the user just types return. This is
5178 useful if the command is time-consuming to run, so that accidental
5179 extra keystrokes don't run the same command many times.
5181 * Send break instead of ^C
5183 The standard remote protocol now includes an option to send a break
5184 rather than a ^C to the target in order to interrupt it. By default,
5185 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5187 * Remote protocol timeout
5189 The standard remote protocol includes a new variable `remotetimeout'
5190 that allows you to set the number of seconds before GDB gives up trying
5191 to read from the target. The default value is 2.
5193 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5195 By default GDB will automatically keep track of objects as they are
5196 loaded and unloaded by the dynamic linker. By using the command `set
5197 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5198 when shared library events occur, thus allowing you to set breakpoints
5199 in shared libraries which are explicitly loaded by the inferior.
5201 Note this feature does not work on hpux8. On hpux9 you must link
5202 /usr/lib/end.o into your program. This feature should work
5203 automatically on hpux10.
5205 * Irix 5.x hardware watchpoint support
5207 Irix 5 configurations now support the use of hardware watchpoints.
5209 * Mips protocol "SYN garbage limit"
5211 When debugging a Mips target using the `target mips' protocol, you
5212 may set the number of characters that GDB will ignore by setting
5213 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5214 every character. The default value is 1050.
5216 * Recording and replaying remote debug sessions
5218 If you set `remotelogfile' to the name of a file, gdb will write to it
5219 a recording of a remote debug session. This recording may then be
5220 replayed back to gdb using "gdbreplay". See gdbserver/README for
5221 details. This is useful when you have a problem with GDB while doing
5222 remote debugging; you can make a recording of the session and send it
5223 to someone else, who can then recreate the problem.
5225 * Speedups for remote debugging
5227 GDB includes speedups for downloading and stepping MIPS systems using
5228 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5229 and more efficient S-record downloading.
5231 * Memory use reductions and statistics collection
5233 GDB now uses less memory and reports statistics about memory usage.
5234 Try the `maint print statistics' command, for example.
5236 *** Changes in GDB-4.15:
5238 * Psymtabs for XCOFF
5240 The symbol reader for AIX GDB now uses partial symbol tables. This
5241 can greatly improve startup time, especially for large executables.
5243 * Remote targets use caching
5245 Remote targets now use a data cache to speed up communication with the
5246 remote side. The data cache could lead to incorrect results because
5247 it doesn't know about volatile variables, thus making it impossible to
5248 debug targets which use memory mapped I/O devices. `set remotecache
5249 off' turns the the data cache off.
5251 * Remote targets may have threads
5253 The standard remote protocol now includes support for multiple threads
5254 in the target system, using new protocol commands 'H' and 'T'. See
5255 gdb/remote.c for details.
5259 If GDB is configured with `--enable-netrom', then it will include
5260 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5261 acts as though it is a bank of ROM on the target board, but you can
5262 write into it over the network. GDB's support consists only of
5263 support for fast loading into the emulated ROM; to debug, you must use
5264 another protocol, such as standard remote protocol. The usual
5265 sequence is something like
5267 target nrom <netrom-hostname>
5269 target remote <netrom-hostname>:1235
5273 GDB now includes support for the Apple Macintosh, as a host only. It
5274 may be run as either an MPW tool or as a standalone application, and
5275 it can debug through the serial port. All the usual GDB commands are
5276 available, but to the target command, you must supply "serial" as the
5277 device type instead of "/dev/ttyXX". See mpw-README in the main
5278 directory for more information on how to build. The MPW configuration
5279 scripts */mpw-config.in support only a few targets, and only the
5280 mips-idt-ecoff target has been tested.
5284 GDB configuration now uses autoconf. This is not user-visible,
5285 but does simplify configuration and building.
5289 GDB now supports hpux10.
5291 *** Changes in GDB-4.14:
5293 * New native configurations
5295 x86 FreeBSD i[345]86-*-freebsd
5296 x86 NetBSD i[345]86-*-netbsd
5297 NS32k NetBSD ns32k-*-netbsd
5298 Sparc NetBSD sparc-*-netbsd
5302 A29K VxWorks a29k-*-vxworks
5303 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5304 CPU32 EST-300 emulator m68*-*-est*
5305 PowerPC ELF powerpc-*-elf
5308 * Alpha OSF/1 support for procfs
5310 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5311 possible to attach to running processes. As the mounting of the /proc
5312 filesystem is optional on the Alpha, GDB automatically determines
5313 the availability of /proc during startup. This can lead to problems
5314 if /proc is unmounted after GDB has been started.
5316 * Arguments to user-defined commands
5318 User commands may accept up to 10 arguments separated by whitespace.
5319 Arguments are accessed within the user command via $arg0..$arg9. A
5322 print $arg0 + $arg1 + $arg2
5324 To execute the command use:
5327 Defines the command "adder" which prints the sum of its three arguments.
5328 Note the arguments are text substitutions, so they may reference variables,
5329 use complex expressions, or even perform inferior function calls.
5331 * New `if' and `while' commands
5333 This makes it possible to write more sophisticated user-defined
5334 commands. Both commands take a single argument, which is the
5335 expression to evaluate, and must be followed by the commands to
5336 execute, one per line, if the expression is nonzero, the list being
5337 terminated by the word `end'. The `if' command list may include an
5338 `else' word, which causes the following commands to be executed only
5339 if the expression is zero.
5341 * Fortran source language mode
5343 GDB now includes partial support for Fortran 77. It will recognize
5344 Fortran programs and can evaluate a subset of Fortran expressions, but
5345 variables and functions may not be handled correctly. GDB will work
5346 with G77, but does not yet know much about symbols emitted by other
5349 * Better HPUX support
5351 Most debugging facilities now work on dynamic executables for HPPAs
5352 running hpux9 or later. You can attach to running dynamically linked
5353 processes, but by default the dynamic libraries will be read-only, so
5354 for instance you won't be able to put breakpoints in them. To change
5355 that behavior do the following before running the program:
5361 This will cause the libraries to be mapped private and read-write.
5362 To revert to the normal behavior, do this:
5368 You cannot set breakpoints or examine data in the library until after
5369 the library is loaded if the function/data symbols do not have
5372 GDB can now also read debug symbols produced by the HP C compiler on
5373 HPPAs (sorry, no C++, Fortran or 68k support).
5375 * Target byte order now dynamically selectable
5377 You can choose which byte order to use with a target system, via the
5378 commands "set endian big" and "set endian little", and you can see the
5379 current setting by using "show endian". You can also give the command
5380 "set endian auto", in which case GDB will use the byte order
5381 associated with the executable. Currently, only embedded MIPS
5382 configurations support dynamic selection of target byte order.
5384 * New DOS host serial code
5386 This version uses DPMI interrupts to handle buffered I/O, so you
5387 no longer need to run asynctsr when debugging boards connected to
5390 *** Changes in GDB-4.13:
5392 * New "complete" command
5394 This lists all the possible completions for the rest of the line, if it
5395 were to be given as a command itself. This is intended for use by emacs.
5397 * Trailing space optional in prompt
5399 "set prompt" no longer adds a space for you after the prompt you set. This
5400 allows you to set a prompt which ends in a space or one that does not.
5402 * Breakpoint hit counts
5404 "info break" now displays a count of the number of times the breakpoint
5405 has been hit. This is especially useful in conjunction with "ignore"; you
5406 can ignore a large number of breakpoint hits, look at the breakpoint info
5407 to see how many times the breakpoint was hit, then run again, ignoring one
5408 less than that number, and this will get you quickly to the last hit of
5411 * Ability to stop printing at NULL character
5413 "set print null-stop" will cause GDB to stop printing the characters of
5414 an array when the first NULL is encountered. This is useful when large
5415 arrays actually contain only short strings.
5417 * Shared library breakpoints
5419 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5420 breakpoints in shared libraries before the executable is run.
5422 * Hardware watchpoints
5424 There is a new hardware breakpoint for the watch command for sparclite
5425 targets. See gdb/sparclite/hw_breakpoint.note.
5427 Hardware watchpoints are also now supported under GNU/Linux.
5431 Annotations have been added. These are for use with graphical interfaces,
5432 and are still experimental. Currently only gdba.el uses these.
5434 * Improved Irix 5 support
5436 GDB now works properly with Irix 5.2.
5438 * Improved HPPA support
5440 GDB now works properly with the latest GCC and GAS.
5442 * New native configurations
5444 Sequent PTX4 i[34]86-sequent-ptx4
5445 HPPA running OSF/1 hppa*-*-osf*
5446 Atari TT running SVR4 m68*-*-sysv4*
5447 RS/6000 LynxOS rs6000-*-lynxos*
5451 OS/9000 i[34]86-*-os9k
5452 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5455 * Hitachi SH7000 and E7000-PC ICE support
5457 There is now support for communicating with the Hitachi E7000-PC ICE.
5458 This is available automatically when GDB is configured for the SH.
5462 As usual, a variety of small fixes and improvements, both generic
5463 and configuration-specific. See the ChangeLog for more detail.
5465 *** Changes in GDB-4.12:
5467 * Irix 5 is now supported
5471 GDB-4.12 on the HPPA has a number of changes which make it unable
5472 to debug the output from the currently released versions of GCC and
5473 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5474 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5475 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5478 *** Changes in GDB-4.11:
5480 * User visible changes:
5484 The "set remotedebug" option is now consistent between the mips remote
5485 target, remote targets using the gdb-specific protocol, UDI (AMD's
5486 debug protocol for the 29k) and the 88k bug monitor. It is now an
5487 integer specifying a debug level (normally 0 or 1, but 2 means more
5488 debugging info for the mips target).
5490 * DEC Alpha native support
5492 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5493 debug info, but GDB works fairly well with the DEC compiler and should
5494 work with a future GCC release. See the README file for a few
5495 Alpha-specific notes.
5497 * Preliminary thread implementation
5499 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5501 * LynxOS native and target support for 386
5503 This release has been hosted on LynxOS 2.2, and also can be configured
5504 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5507 * Improvements in C++ mangling/demangling.
5509 This release has much better g++ debugging, specifically in name
5510 mangling/demangling, virtual function calls, print virtual table,
5511 call methods, ...etc.
5513 *** Changes in GDB-4.10:
5515 * User visible changes:
5517 Remote debugging using the GDB-specific (`target remote') protocol now
5518 supports the `load' command. This is only useful if you have some
5519 other way of getting the stub to the target system, and you can put it
5520 somewhere in memory where it won't get clobbered by the download.
5522 Filename completion now works.
5524 When run under emacs mode, the "info line" command now causes the
5525 arrow to point to the line specified. Also, "info line" prints
5526 addresses in symbolic form (as well as hex).
5528 All vxworks based targets now support a user settable option, called
5529 vxworks-timeout. This option represents the number of seconds gdb
5530 should wait for responses to rpc's. You might want to use this if
5531 your vxworks target is, perhaps, a slow software simulator or happens
5532 to be on the far side of a thin network line.
5536 This release contains support for using a DEC alpha as a GDB host for
5537 cross debugging. Native alpha debugging is not supported yet.
5540 *** Changes in GDB-4.9:
5544 This is the first GDB release which is accompanied by a matching testsuite.
5545 The testsuite requires installation of dejagnu, which should be available
5546 via ftp from most sites that carry GNU software.
5550 'Cfront' style demangling has had its name changed to 'ARM' style, to
5551 emphasize that it was written from the specifications in the C++ Annotated
5552 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5553 disclaimers, it still generated too much confusion with users attempting to
5554 use gdb with AT&T cfront.
5558 GDB now uses a standard remote interface to a simulator library.
5559 So far, the library contains simulators for the Zilog Z8001/2, the
5560 Hitachi H8/300, H8/500 and Super-H.
5562 * New targets supported
5564 H8/300 simulator h8300-hitachi-hms or h8300hms
5565 H8/500 simulator h8500-hitachi-hms or h8500hms
5566 SH simulator sh-hitachi-hms or sh
5567 Z8000 simulator z8k-zilog-none or z8ksim
5568 IDT MIPS board over serial line mips-idt-ecoff
5570 Cross-debugging to GO32 targets is supported. It requires a custom
5571 version of the i386-stub.c module which is integrated with the
5572 GO32 memory extender.
5574 * New remote protocols
5576 MIPS remote debugging protocol.
5578 * New source languages supported
5580 This version includes preliminary support for Chill, a Pascal like language
5581 used by telecommunications companies. Chill support is also being integrated
5582 into the GNU compiler, but we don't know when it will be publically available.
5585 *** Changes in GDB-4.8:
5587 * HP Precision Architecture supported
5589 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5590 version of this support was available as a set of patches from the
5591 University of Utah. GDB does not support debugging of programs
5592 compiled with the HP compiler, because HP will not document their file
5593 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5594 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5596 Many problems in the preliminary version have been fixed.
5598 * Faster and better demangling
5600 We have improved template demangling and fixed numerous bugs in the GNU style
5601 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5602 character types (wchar_t) are now supported. Demangling of each symbol is now
5603 only done once, and is cached when the symbol table for a file is read in.
5604 This results in a small increase in memory usage for C programs, a moderate
5605 increase in memory usage for C++ programs, and a fantastic speedup in
5608 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5609 from the specifications in the Annotated Reference Manual, which AT&T's
5610 compiler does not actually implement.
5612 * G++ multiple inheritance compiler problem
5614 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5615 inheritance lattices was reworked to properly discover ambiguities. We
5616 recently found an example which causes this new algorithm to fail in a
5617 very subtle way, producing bad debug information for those classes.
5618 The file 'gcc.patch' (in this directory) can be applied to gcc to
5619 circumvent the problem. A future GCC release will contain a complete
5622 The previous G++ debug info problem (mentioned below for the gdb-4.7
5623 release) is fixed in gcc version 2.3.2.
5625 * Improved configure script
5627 The `configure' script will now attempt to guess your system type if
5628 you don't supply a host system type. The old scheme of supplying a
5629 host system triplet is preferable over using this. All the magic is
5630 done in the new `config.guess' script. Examine it for details.
5632 We have also brought our configure script much more in line with the FSF's
5633 version. It now supports the --with-xxx options. In particular,
5634 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5635 The resulting GDB will not be able to read arbitrary object file formats --
5636 only the format ``expected'' to be used on the configured target system.
5637 We hope to make this the default in a future release.
5639 * Documentation improvements
5641 There's new internal documentation on how to modify GDB, and how to
5642 produce clean changes to the code. We implore people to read it
5643 before submitting changes.
5645 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5646 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5647 `info' files are also provided. To build `info' files from scratch,
5648 you will need the latest `makeinfo' release, which will be available in
5649 a future texinfo-X.Y release.
5651 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5652 We're not sure exactly which versions have this problem, but it has
5653 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5654 or better. If that isn't possible, there is a patch in
5655 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5656 around this problem.
5660 GDB now supports array constants that can be used in expressions typed in by
5661 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5662 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5665 The new directory `gdb/sparclite' contains a program that demonstrates
5666 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5668 * New native hosts supported
5670 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5671 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5673 * New targets supported
5675 AMD 29k family via UDI a29k-amd-udi or udi29k
5677 * New file formats supported
5679 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5680 HPUX core files, and SCO 3.2v2 core files.
5684 Attaching to processes now works again; thanks for the many bug reports.
5686 We have also stomped on a bunch of core dumps caused by
5687 printf_filtered("%s") problems.
5689 We eliminated a copyright problem on the rpc and ptrace header files
5690 for VxWorks, which was discovered at the last minute during the 4.7
5691 release. You should now be able to build a VxWorks GDB.
5693 You can now interrupt gdb while an attached process is running. This
5694 will cause the attached process to stop, and give control back to GDB.
5696 We fixed problems caused by using too many file descriptors
5697 for reading symbols from object files and libraries. This was
5698 especially a problem for programs that used many (~100) shared
5701 The `step' command now only enters a subroutine if there is line number
5702 information for the subroutine. Otherwise it acts like the `next'
5703 command. Previously, `step' would enter subroutines if there was
5704 any debugging information about the routine. This avoids problems
5705 when using `cc -g1' on MIPS machines.
5707 * Internal improvements
5709 GDB's internal interfaces have been improved to make it easier to support
5710 debugging of multiple languages in the future.
5712 GDB now uses a common structure for symbol information internally.
5713 Minimal symbols (derived from linkage symbols in object files), partial
5714 symbols (from a quick scan of debug information), and full symbols
5715 contain a common subset of information, making it easier to write
5716 shared code that handles any of them.
5718 * New command line options
5720 We now accept --silent as an alias for --quiet.
5724 The memory-mapped-malloc library is now licensed under the GNU Library
5725 General Public License.
5727 *** Changes in GDB-4.7:
5729 * Host/native/target split
5731 GDB has had some major internal surgery to untangle the support for
5732 hosts and remote targets. Now, when you configure GDB for a remote
5733 target, it will no longer load in all of the support for debugging
5734 local programs on the host. When fully completed and tested, this will
5735 ensure that arbitrary host/target combinations are possible.
5737 The primary conceptual shift is to separate the non-portable code in
5738 GDB into three categories. Host specific code is required any time GDB
5739 is compiled on that host, regardless of the target. Target specific
5740 code relates to the peculiarities of the target, but can be compiled on
5741 any host. Native specific code is everything else: it can only be
5742 built when the host and target are the same system. Child process
5743 handling and core file support are two common `native' examples.
5745 GDB's use of /proc for controlling Unix child processes is now cleaner.
5746 It has been split out into a single module under the `target_ops' vector,
5747 plus two native-dependent functions for each system that uses /proc.
5749 * New hosts supported
5751 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5752 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5753 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5755 * New targets supported
5757 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5758 68030 and CPU32 m68030-*-*, m68332-*-*
5760 * New native hosts supported
5762 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5763 (386bsd is not well tested yet)
5764 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5766 * New file formats supported
5768 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5769 supports reading of `a.out.adobe' object files, which are an a.out
5770 format extended with minimal information about multiple sections.
5774 `show copying' is the same as the old `info copying'.
5775 `show warranty' is the same as `info warrantee'.
5776 These were renamed for consistency. The old commands continue to work.
5778 `info handle' is a new alias for `info signals'.
5780 You can now define pre-command hooks, which attach arbitrary command
5781 scripts to any command. The commands in the hook will be executed
5782 prior to the user's command. You can also create a hook which will be
5783 executed whenever the program stops. See gdb.texinfo.
5787 We now deal with Cfront style name mangling, and can even extract type
5788 info from mangled symbols. GDB can automatically figure out which
5789 symbol mangling style your C++ compiler uses.
5791 Calling of methods and virtual functions has been improved as well.
5795 The crash that occured when debugging Sun Ansi-C compiled binaries is
5796 fixed. This was due to mishandling of the extra N_SO stabs output
5799 We also finally got Ultrix 4.2 running in house, and fixed core file
5800 support, with help from a dozen people on the net.
5802 John M. Farrell discovered that the reason that single-stepping was so
5803 slow on all of the Mips based platforms (primarily SGI and DEC) was
5804 that we were trying to demangle and lookup a symbol used for internal
5805 purposes on every instruction that was being stepped through. Changing
5806 the name of that symbol so that it couldn't be mistaken for a C++
5807 mangled symbol sped things up a great deal.
5809 Rich Pixley sped up symbol lookups in general by getting much smarter
5810 about when C++ symbol mangling is necessary. This should make symbol
5811 completion (TAB on the command line) much faster. It's not as fast as
5812 we'd like, but it's significantly faster than gdb-4.6.
5816 A new user controllable variable 'call_scratch_address' can
5817 specify the location of a scratch area to be used when GDB
5818 calls a function in the target. This is necessary because the
5819 usual method of putting the scratch area on the stack does not work
5820 in systems that have separate instruction and data spaces.
5822 We integrated changes to support the 29k UDI (Universal Debugger
5823 Interface), but discovered at the last minute that we didn't have all
5824 of the appropriate copyright paperwork. We are working with AMD to
5825 resolve this, and hope to have it available soon.
5829 We have sped up the remote serial line protocol, especially for targets
5830 with lots of registers. It now supports a new `expedited status' ('T')
5831 message which can be used in place of the existing 'S' status message.
5832 This allows the remote stub to send only the registers that GDB
5833 needs to make a quick decision about single-stepping or conditional
5834 breakpoints, eliminating the need to fetch the entire register set for
5835 each instruction being stepped through.
5837 The GDB remote serial protocol now implements a write-through cache for
5838 registers, only re-reading the registers if the target has run.
5840 There is also a new remote serial stub for SPARC processors. You can
5841 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5842 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5843 processor with a serial port.
5847 Configure.in files have become much easier to read and modify. A new
5848 `table driven' format makes it more obvious what configurations are
5849 supported, and what files each one uses.
5853 There is a new opcodes library which will eventually contain all of the
5854 disassembly routines and opcode tables. At present, it only contains
5855 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5856 disassembler (binutils/objdump) to share these routines.
5858 The libiberty library is now copylefted under the GNU Library General
5859 Public License. This allows more liberal use, and was done so libg++
5860 can use it. This makes no difference to GDB, since the Library License
5861 grants all the rights from the General Public License.
5865 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5866 reference to the stabs symbol info used by the debugger. It is (as far
5867 as we know) the only published document on this fascinating topic. We
5868 encourage you to read it, compare it to the stabs information on your
5869 system, and send improvements on the document in general (to
5870 bug-gdb@prep.ai.mit.edu).
5872 And, of course, many bugs have been fixed.
5875 *** Changes in GDB-4.6:
5877 * Better support for C++ function names
5879 GDB now accepts as input the "demangled form" of C++ overloaded function
5880 names and member function names, and can do command completion on such names
5881 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5882 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5883 Make use of command completion, it is your friend.
5885 GDB also now accepts a variety of C++ mangled symbol formats. They are
5886 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5887 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5888 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5889 for the list of formats.
5891 * G++ symbol mangling problem
5893 Recent versions of gcc have a bug in how they emit debugging information for
5894 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5895 directory) can be applied to gcc to fix the problem. Alternatively, if you
5896 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5897 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5898 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5901 * New 'maintenance' command
5903 All of the commands related to hacking GDB internals have been moved out of
5904 the main command set, and now live behind the 'maintenance' command. This
5905 can also be abbreviated as 'mt'. The following changes were made:
5907 dump-me -> maintenance dump-me
5908 info all-breakpoints -> maintenance info breakpoints
5909 printmsyms -> maintenance print msyms
5910 printobjfiles -> maintenance print objfiles
5911 printpsyms -> maintenance print psymbols
5912 printsyms -> maintenance print symbols
5914 The following commands are new:
5916 maintenance demangle Call internal GDB demangler routine to
5917 demangle a C++ link name and prints the result.
5918 maintenance print type Print a type chain for a given symbol
5920 * Change to .gdbinit file processing
5922 We now read the $HOME/.gdbinit file before processing the argv arguments
5923 (e.g. reading symbol files or core files). This allows global parameters to
5924 be set, which will apply during the symbol reading. The ./.gdbinit is still
5925 read after argv processing.
5927 * New hosts supported
5929 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5931 GNU/Linux support i386-unknown-linux or linux
5933 We are also including code to support the HP/PA running BSD and HPUX. This
5934 is almost guaranteed not to work, as we didn't have time to test or build it
5935 for this release. We are including it so that the more adventurous (or
5936 masochistic) of you can play with it. We also had major problems with the
5937 fact that the compiler that we got from HP doesn't support the -g option.
5940 * New targets supported
5942 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5944 * More smarts about finding #include files
5946 GDB now remembers the compilation directory for all include files, and for
5947 all files from which C is generated (like yacc and lex sources). This
5948 greatly improves GDB's ability to find yacc/lex sources, and include files,
5949 especially if you are debugging your program from a directory different from
5950 the one that contains your sources.
5952 We also fixed a bug which caused difficulty with listing and setting
5953 breakpoints in include files which contain C code. (In the past, you had to
5954 try twice in order to list an include file that you hadn't looked at before.)
5956 * Interesting infernals change
5958 GDB now deals with arbitrary numbers of sections, where the symbols for each
5959 section must be relocated relative to that section's landing place in the
5960 target's address space. This work was needed to support ELF with embedded
5961 stabs used by Solaris-2.0.
5963 * Bug fixes (of course!)
5965 There have been loads of fixes for the following things:
5966 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5967 i960, stabs, DOS(GO32), procfs, etc...
5969 See the ChangeLog for details.
5971 *** Changes in GDB-4.5:
5973 * New machines supported (host and target)
5975 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5977 SGI Irix-4.x mips-sgi-irix4 or iris4
5979 * New malloc package
5981 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5982 Mmalloc is capable of handling mutiple heaps of memory. It is also
5983 capable of saving a heap to a file, and then mapping it back in later.
5984 This can be used to greatly speedup the startup of GDB by using a
5985 pre-parsed symbol table which lives in a mmalloc managed heap. For
5986 more details, please read mmalloc/mmalloc.texi.
5990 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5991 'help info proc' for details.
5993 * MIPS ecoff symbol table format
5995 The code that reads MIPS symbol table format is now supported on all hosts.
5996 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5999 * File name changes for MS-DOS
6001 Many files in the config directories have been renamed to make it easier to
6002 support GDB on MS-DOSe systems (which have very restrictive file name
6003 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6004 environment) is close to working but has some remaining problems. Note
6005 that debugging of DOS programs is not supported, due to limitations
6006 in the ``operating system'', but it can be used to host cross-debugging.
6008 * Cross byte order fixes
6010 Many fixes have been made to support cross debugging of Sparc and MIPS
6011 targets from hosts whose byte order differs.
6013 * New -mapped and -readnow options
6015 If memory-mapped files are available on your system through the 'mmap'
6016 system call, you can use the -mapped option on the `file' or
6017 `symbol-file' commands to cause GDB to write the symbols from your
6018 program into a reusable file. If the program you are debugging is
6019 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6020 Future GDB debugging sessions will notice the presence of this file,
6021 and will quickly map in symbol information from it, rather than reading
6022 the symbol table from the executable program. Using the '-mapped'
6023 option in a GDB `file' or `symbol-file' command has the same effect as
6024 starting GDB with the '-mapped' command-line option.
6026 You can cause GDB to read the entire symbol table immediately by using
6027 the '-readnow' option with any of the commands that load symbol table
6028 information (or on the GDB command line). This makes the command
6029 slower, but makes future operations faster.
6031 The -mapped and -readnow options are typically combined in order to
6032 build a `fred.syms' file that contains complete symbol information.
6033 A simple GDB invocation to do nothing but build a `.syms' file for future
6036 gdb -batch -nx -mapped -readnow programname
6038 The `.syms' file is specific to the host machine on which GDB is run.
6039 It holds an exact image of GDB's internal symbol table. It cannot be
6040 shared across multiple host platforms.
6042 * longjmp() handling
6044 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6045 siglongjmp() without losing control. This feature has not yet been ported to
6046 all systems. It currently works on many 386 platforms, all MIPS-based
6047 platforms (SGI, DECstation, etc), and Sun3/4.
6051 Preliminary work has been put in to support the new Solaris OS from Sun. At
6052 this time, it can control and debug processes, but it is not capable of
6057 As always, many many bug fixes. The major areas were with g++, and mipsread.
6058 People using the MIPS-based platforms should experience fewer mysterious
6059 crashes and trashed symbol tables.
6061 *** Changes in GDB-4.4:
6063 * New machines supported (host and target)
6065 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6067 BSD Reno on Vax vax-dec-bsd
6068 Ultrix on Vax vax-dec-ultrix
6070 * New machines supported (target)
6072 AMD 29000 embedded, using EBMON a29k-none-none
6076 GDB continues to improve its handling of C++. `References' work better.
6077 The demangler has also been improved, and now deals with symbols mangled as
6078 per the Annotated C++ Reference Guide.
6080 GDB also now handles `stabs' symbol information embedded in MIPS
6081 `ecoff' symbol tables. Since the ecoff format was not easily
6082 extensible to handle new languages such as C++, this appeared to be a
6083 good way to put C++ debugging info into MIPS binaries. This option
6084 will be supported in the GNU C compiler, version 2, when it is
6087 * New features for SVR4
6089 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6090 shared libraries. Debugging dynamically linked programs should present
6091 only minor differences from debugging statically linked programs.
6093 The `info proc' command will print out information about any process
6094 on an SVR4 system (including the one you are debugging). At the moment,
6095 it prints the address mappings of the process.
6097 If you bring up GDB on another SVR4 system, please send mail to
6098 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6100 * Better dynamic linking support in SunOS
6102 Reading symbols from shared libraries which contain debugging symbols
6103 now works properly. However, there remain issues such as automatic
6104 skipping of `transfer vector' code during function calls, which
6105 make it harder to debug code in a shared library, than to debug the
6106 same code linked statically.
6110 GDB is now using the latest `getopt' routines from the FSF. This
6111 version accepts the -- prefix for options with long names. GDB will
6112 continue to accept the old forms (-option and +option) as well.
6113 Various single letter abbreviations for options have been explicity
6114 added to the option table so that they won't get overshadowed in the
6115 future by other options that begin with the same letter.
6119 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6120 Many assorted bugs have been handled. Many more remain to be handled.
6121 See the various ChangeLog files (primarily in gdb and bfd) for details.
6124 *** Changes in GDB-4.3:
6126 * New machines supported (host and target)
6128 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6129 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6130 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6132 * Almost SCO Unix support
6134 We had hoped to support:
6135 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6136 (except for core file support), but we discovered very late in the release
6137 that it has problems with process groups that render gdb unusable. Sorry
6138 about that. I encourage people to fix it and post the fixes.
6140 * Preliminary ELF and DWARF support
6142 GDB can read ELF object files on System V Release 4, and can handle
6143 debugging records for C, in DWARF format, in ELF files. This support
6144 is preliminary. If you bring up GDB on another SVR4 system, please
6145 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6150 GDB now uses the latest `readline' library. One user-visible change
6151 is that two tabs will list possible command completions, which previously
6152 required typing M-? (meta-question mark, or ESC ?).
6156 The `stepi' bug that many of you noticed has been squashed.
6157 Many bugs in C++ have been handled. Many more remain to be handled.
6158 See the various ChangeLog files (primarily in gdb and bfd) for details.
6160 * State of the MIPS world (in case you wondered):
6162 GDB can understand the symbol tables emitted by the compilers
6163 supplied by most vendors of MIPS-based machines, including DEC. These
6164 symbol tables are in a format that essentially nobody else uses.
6166 Some versions of gcc come with an assembler post-processor called
6167 mips-tfile. This program is required if you want to do source-level
6168 debugging of gcc-compiled programs. I believe FSF does not ship
6169 mips-tfile with gcc version 1, but it will eventually come with gcc
6172 Debugging of g++ output remains a problem. g++ version 1.xx does not
6173 really support it at all. (If you're lucky, you should be able to get
6174 line numbers and stack traces to work, but no parameters or local
6175 variables.) With some work it should be possible to improve the
6178 When gcc version 2 is released, you will have somewhat better luck.
6179 However, even then you will get confusing results for inheritance and
6182 We will eventually provide full debugging of g++ output on
6183 DECstations. This will probably involve some kind of stabs-in-ecoff
6184 encapulation, but the details have not been worked out yet.
6187 *** Changes in GDB-4.2:
6189 * Improved configuration
6191 Only one copy of `configure' exists now, and it is not self-modifying.
6192 Porting BFD is simpler.
6196 The `step' and `next' commands now only stop at the first instruction
6197 of a source line. This prevents the multiple stops that used to occur
6198 in switch statements, for-loops, etc. `Step' continues to stop if a
6199 function that has debugging information is called within the line.
6203 Lots of small bugs fixed. More remain.
6205 * New host supported (not target)
6207 Intel 386 PC clone running Mach i386-none-mach
6210 *** Changes in GDB-4.1:
6212 * Multiple source language support
6214 GDB now has internal scaffolding to handle several source languages.
6215 It determines the type of each source file from its filename extension,
6216 and will switch expression parsing and number formatting to match the
6217 language of the function in the currently selected stack frame.
6218 You can also specifically set the language to be used, with
6219 `set language c' or `set language modula-2'.
6223 GDB now has preliminary support for the GNU Modula-2 compiler,
6224 currently under development at the State University of New York at
6225 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6226 continue through the fall of 1991 and into 1992.
6228 Other Modula-2 compilers are currently not supported, and attempting to
6229 debug programs compiled with them will likely result in an error as the
6230 symbol table is read. Feel free to work on it, though!
6232 There are hooks in GDB for strict type checking and range checking,
6233 in the `Modula-2 philosophy', but they do not currently work.
6237 GDB can now write to executable and core files (e.g. patch
6238 a variable's value). You must turn this switch on, specify
6239 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6240 by assigning a new value to a variable. Modifications take
6243 * Automatic SunOS shared library reading
6245 When you run your program, GDB automatically determines where its
6246 shared libraries (if any) have been loaded, and reads their symbols.
6247 The `share' command is no longer needed. This also works when
6248 examining core files.
6252 You can specify the number of lines that the `list' command shows.
6255 * New machines supported (host and target)
6257 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6258 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6259 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6261 * New hosts supported (not targets)
6263 IBM RT/PC: romp-ibm-aix or rtpc
6265 * New targets supported (not hosts)
6267 AMD 29000 embedded with COFF a29k-none-coff
6268 AMD 29000 embedded with a.out a29k-none-aout
6269 Ultracomputer remote kernel debug a29k-nyu-kern
6271 * New remote interfaces
6277 *** Changes in GDB-4.0:
6281 Wide output is wrapped at good places to make the output more readable.
6283 Gdb now supports cross-debugging from a host machine of one type to a
6284 target machine of another type. Communication with the target system
6285 is over serial lines. The ``target'' command handles connecting to the
6286 remote system; the ``load'' command will download a program into the
6287 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6288 also supports debugging of realtime processes running under VxWorks,
6289 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6290 stub on the target system.
6292 New CPUs supported include the AMD 29000 and Intel 960.
6294 GDB now reads object files and symbol tables via a ``binary file''
6295 library, which allows a single copy of GDB to debug programs of multiple
6296 object file types such as a.out and coff.
6298 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6299 refcard.dvi and refcard.ps are available to format it).
6302 * Control-Variable user interface simplified
6304 All variables that control the operation of the debugger can be set
6305 by the ``set'' command, and displayed by the ``show'' command.
6307 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6308 ``Show prompt'' produces the response:
6309 Gdb's prompt is new-gdb=>.
6311 What follows are the NEW set commands. The command ``help set'' will
6312 print a complete list of old and new set commands. ``help set FOO''
6313 will give a longer description of the variable FOO. ``show'' will show
6314 all of the variable descriptions and their current settings.
6316 confirm on/off: Enables warning questions for operations that are
6317 hard to recover from, e.g. rerunning the program while
6318 it is already running. Default is ON.
6320 editing on/off: Enables EMACS style command line editing
6321 of input. Previous lines can be recalled with
6322 control-P, the current line can be edited with control-B,
6323 you can search for commands with control-R, etc.
6326 history filename NAME: NAME is where the gdb command history
6327 will be stored. The default is .gdb_history,
6328 or the value of the environment variable
6331 history size N: The size, in commands, of the command history. The
6332 default is 256, or the value of the environment variable
6335 history save on/off: If this value is set to ON, the history file will
6336 be saved after exiting gdb. If set to OFF, the
6337 file will not be saved. The default is OFF.
6339 history expansion on/off: If this value is set to ON, then csh-like
6340 history expansion will be performed on
6341 command line input. The default is OFF.
6343 radix N: Sets the default radix for input and output. It can be set
6344 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6345 in the current radix, so "set radix 10" is always a no-op.
6347 height N: This integer value is the number of lines on a page. Default
6348 is 24, the current `stty rows'' setting, or the ``li#''
6349 setting from the termcap entry matching the environment
6352 width N: This integer value is the number of characters on a line.
6353 Default is 80, the current `stty cols'' setting, or the ``co#''
6354 setting from the termcap entry matching the environment
6357 Note: ``set screensize'' is obsolete. Use ``set height'' and
6358 ``set width'' instead.
6360 print address on/off: Print memory addresses in various command displays,
6361 such as stack traces and structure values. Gdb looks
6362 more ``symbolic'' if you turn this off; it looks more
6363 ``machine level'' with it on. Default is ON.
6365 print array on/off: Prettyprint arrays. New convenient format! Default
6368 print demangle on/off: Print C++ symbols in "source" form if on,
6371 print asm-demangle on/off: Same, for assembler level printouts
6374 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6377 * Support for Epoch Environment.
6379 The epoch environment is a version of Emacs v18 with windowing. One
6380 new command, ``inspect'', is identical to ``print'', except that if you
6381 are running in the epoch environment, the value is printed in its own
6385 * Support for Shared Libraries
6387 GDB can now debug programs and core files that use SunOS shared libraries.
6388 Symbols from a shared library cannot be referenced
6389 before the shared library has been linked with the program (this
6390 happens after you type ``run'' and before the function main() is entered).
6391 At any time after this linking (including when examining core files
6392 from dynamically linked programs), gdb reads the symbols from each
6393 shared library when you type the ``sharedlibrary'' command.
6394 It can be abbreviated ``share''.
6396 sharedlibrary REGEXP: Load shared object library symbols for files
6397 matching a unix regular expression. No argument
6398 indicates to load symbols for all shared libraries.
6400 info sharedlibrary: Status of loaded shared libraries.
6405 A watchpoint stops execution of a program whenever the value of an
6406 expression changes. Checking for this slows down execution
6407 tremendously whenever you are in the scope of the expression, but is
6408 quite useful for catching tough ``bit-spreader'' or pointer misuse
6409 problems. Some machines such as the 386 have hardware for doing this
6410 more quickly, and future versions of gdb will use this hardware.
6412 watch EXP: Set a watchpoint (breakpoint) for an expression.
6414 info watchpoints: Information about your watchpoints.
6416 delete N: Deletes watchpoint number N (same as breakpoints).
6417 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6418 enable N: Re-enables watchpoint number N (same as breakpoints).
6421 * C++ multiple inheritance
6423 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6426 * C++ exception handling
6428 Gdb now supports limited C++ exception handling. Besides the existing
6429 ability to breakpoint on an exception handler, gdb can breakpoint on
6430 the raising of an exception (before the stack is peeled back to the
6433 catch FOO: If there is a FOO exception handler in the dynamic scope,
6434 set a breakpoint to catch exceptions which may be raised there.
6435 Multiple exceptions (``catch foo bar baz'') may be caught.
6437 info catch: Lists all exceptions which may be caught in the
6438 current stack frame.
6441 * Minor command changes
6443 The command ``call func (arg, arg, ...)'' now acts like the print
6444 command, except it does not print or save a value if the function's result
6445 is void. This is similar to dbx usage.
6447 The ``up'' and ``down'' commands now always print the frame they end up
6448 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6449 frames without printing.
6451 * New directory command
6453 'dir' now adds directories to the FRONT of the source search path.
6454 The path starts off empty. Source files that contain debug information
6455 about the directory in which they were compiled can be found even
6456 with an empty path; Sun CC and GCC include this information. If GDB can't
6457 find your source file in the current directory, type "dir .".
6459 * Configuring GDB for compilation
6461 For normal use, type ``./configure host''. See README or gdb.texinfo
6464 GDB now handles cross debugging. If you are remotely debugging between
6465 two different machines, type ``./configure host -target=targ''.
6466 Host is the machine where GDB will run; targ is the machine
6467 where the program that you are debugging will run.
projects / external / binutils.git / blob