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 maint info line-table REGEXP
35 Display the contents of GDB's internal line table data struture.
37 *** Changes in GDB 7.11
39 * GDB now supports debugging kernel-based threads on FreeBSD.
41 * Per-inferior thread numbers
43 Thread numbers are now per inferior instead of global. If you're
44 debugging multiple inferiors, GDB displays thread IDs using a
45 qualified INF_NUM.THR_NUM form. For example:
49 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
50 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
51 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
52 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
54 As consequence, thread numbers as visible in the $_thread
55 convenience variable and in Python's InferiorThread.num attribute
56 are no longer unique between inferiors.
58 GDB now maintains a second thread ID per thread, referred to as the
59 global thread ID, which is the new equivalent of thread numbers in
60 previous releases. See also $_gthread below.
62 For backwards compatibility, MI's thread IDs always refer to global
65 * Commands that accept thread IDs now accept the qualified
66 INF_NUM.THR_NUM form as well. For example:
69 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
72 * In commands that accept a list of thread IDs, you can now refer to
73 all threads of an inferior using a star wildcard. GDB accepts
74 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
75 refer to all threads of the current inferior. For example, "info
78 * You can use "info threads -gid" to display the global thread ID of
81 * The new convenience variable $_gthread holds the global number of
84 * The new convenience variable $_inferior holds the number of the
87 * GDB now displays the ID and name of the thread that hit a breakpoint
88 or received a signal, if your program is multi-threaded. For
91 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
92 Thread 1 "main" received signal SIGINT, Interrupt.
94 * Record btrace now supports non-stop mode.
96 * Support for tracepoints on aarch64-linux was added in GDBserver.
98 * The 'record instruction-history' command now indicates speculative execution
99 when using the Intel Processor Trace recording format.
101 * GDB now allows users to specify explicit locations, bypassing
102 the linespec parser. This feature is also available to GDB/MI
105 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
106 GDB now is able to debug both AArch64 applications and ARM applications
109 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
110 including JIT compiling fast tracepoint's conditional expression bytecode
113 * GDB now supports displaced stepping on AArch64 GNU/Linux.
115 * "info threads", "info inferiors", "info display", "info checkpoints"
116 and "maint info program-spaces" now list the corresponding items in
117 ascending ID order, for consistency with all other "info" commands.
119 * In Ada, the overloads selection menu has been enhanced to display the
120 parameter types and the return types for the matching overloaded subprograms.
124 maint set target-non-stop (on|off|auto)
125 maint show target-non-stop
126 Control whether GDB targets always operate in non-stop mode even if
127 "set non-stop" is "off". The default is "auto", meaning non-stop
128 mode is enabled if supported by the target.
130 maint set bfd-sharing
131 maint show bfd-sharing
132 Control the reuse of bfd objects.
136 Control display of debugging info regarding bfd caching.
140 Control display of debugging info regarding FreeBSD threads.
142 set remote multiprocess-extensions-packet
143 show remote multiprocess-extensions-packet
144 Set/show the use of the remote protocol multiprocess extensions.
146 set remote thread-events
147 show remote thread-events
148 Set/show the use of thread create/exit events.
150 set ada print-signatures on|off
151 show ada print-signatures"
152 Control whether parameter types and return types are displayed in overloads
153 selection menus. It is activaled (@code{on}) by default.
157 Controls the maximum size of memory, in bytes, that GDB will
158 allocate for value contents. Prevents incorrect programs from
159 causing GDB to allocate overly large buffers. Default is 64k.
161 * The "disassemble" command accepts a new modifier: /s.
162 It prints mixed source+disassembly like /m with two differences:
163 - disassembled instructions are now printed in program order, and
164 - and source for all relevant files is now printed.
165 The "/m" option is now considered deprecated: its "source-centric"
166 output hasn't proved useful in practice.
168 * The "record instruction-history" command accepts a new modifier: /s.
169 It behaves exactly like /m and prints mixed source+disassembly.
171 * The "set scheduler-locking" command supports a new mode "replay".
172 It behaves like "off" in record mode and like "on" in replay mode.
174 * Support for various ROM monitors has been removed:
176 target dbug dBUG ROM monitor for Motorola ColdFire
177 target picobug Motorola picobug monitor
178 target dink32 DINK32 ROM monitor for PowerPC
179 target m32r Renesas M32R/D ROM monitor
180 target mon2000 mon2000 ROM monitor
181 target ppcbug PPCBUG ROM monitor for PowerPC
183 * Support for reading/writing memory and extracting values on architectures
184 whose memory is addressable in units of any integral multiple of 8 bits.
189 Indicates that an exec system call was executed.
191 exec-events feature in qSupported
192 The qSupported packet allows GDB to request support for exec
193 events using the new 'gdbfeature' exec-event, and the qSupported
194 response can contain the corresponding 'stubfeature'. Set and
195 show commands can be used to display whether these features are enabled.
198 Equivalent to interrupting with the ^C character, but works in
201 thread created stop reason (T05 create:...)
202 Indicates that the thread was just created and is stopped at entry.
204 thread exit stop reply (w exitcode;tid)
205 Indicates that the thread has terminated.
208 Enables/disables thread create and exit event reporting. For
209 example, this is used in non-stop mode when GDB stops a set of
210 threads and synchronously waits for the their corresponding stop
211 replies. Without exit events, if one of the threads exits, GDB
212 would hang forever not knowing that it should no longer expect a
213 stop for that same thread.
217 Indicates that there are no resumed threads left in the target (all
218 threads are stopped). The remote stub reports support for this stop
219 reply to GDB's qSupported query.
221 QCatchSyscalls:1 [;SYSNO]...
223 Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
224 catching syscalls from the inferior process.
226 syscall_entry stop reason
227 Indicates that a syscall was just called.
229 syscall_return stop reason
230 Indicates that a syscall just returned.
232 QCatchSyscalls:1 in qSupported
233 The qSupported packet may now include QCatchSyscalls:1 in the reply
234 to indicate support for catching syscalls.
236 * Extended-remote exec events
238 ** GDB now has support for exec events on extended-remote Linux targets.
239 For such targets with Linux kernels 2.5.46 and later, this enables
240 follow-exec-mode and exec catchpoints.
242 set remote exec-event-feature-packet
243 show remote exec-event-feature-packet
244 Set/show the use of the remote exec event feature.
246 * Thread names in remote protocol
248 The reply to qXfer:threads:read may now include a name attribute for each
251 * Target remote mode fork and exec events
253 ** GDB now has support for fork and exec events on target remote mode
254 Linux targets. For such targets with Linux kernels 2.5.46 and later,
255 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
256 fork and exec catchpoints.
258 * Remote syscall events
260 ** GDB now has support for catch syscall on remote Linux targets,
261 currently enabled on x86/x86_64 architectures.
263 set remote catch-syscall-packet
264 show remote catch-syscall-packet
265 Set/show the use of the remote catch syscall feature.
269 ** The -var-set-format command now accepts the zero-hexadecimal
270 format. It outputs data in hexadecimal format with zero-padding on the
275 ** gdb.InferiorThread objects have a new attribute "global_num",
276 which refers to the thread's global thread ID. The existing
277 "num" attribute now refers to the thread's per-inferior number.
278 See "Per-inferior thread numbers" above.
279 ** gdb.InferiorThread objects have a new attribute "inferior", which
280 is the Inferior object the thread belongs to.
282 *** Changes in GDB 7.10
284 * Support for process record-replay and reverse debugging on aarch64*-linux*
285 targets has been added. GDB now supports recording of A64 instruction set
286 including advance SIMD instructions.
288 * Support for Sun's version of the "stabs" debug file format has been removed.
290 * GDB now honors the content of the file /proc/PID/coredump_filter
291 (PID is the process ID) on GNU/Linux systems. This file can be used
292 to specify the types of memory mappings that will be included in a
293 corefile. For more information, please refer to the manual page of
294 "core(5)". GDB also has a new command: "set use-coredump-filter
295 on|off". It allows to set whether GDB will read the content of the
296 /proc/PID/coredump_filter file when generating a corefile.
298 * The "info os" command on GNU/Linux can now display information on
300 "info os cpus" Listing of all cpus/cores on the system
302 * GDB has two new commands: "set serial parity odd|even|none" and
303 "show serial parity". These allows to set or show parity for the
306 * The "info source" command now displays the producer string if it was
307 present in the debug info. This typically includes the compiler version
308 and may include things like its command line arguments.
310 * The "info dll", an alias of the "info sharedlibrary" command,
311 is now available on all platforms.
313 * Directory names supplied to the "set sysroot" commands may be
314 prefixed with "target:" to tell GDB to access shared libraries from
315 the target system, be it local or remote. This replaces the prefix
316 "remote:". The default sysroot has been changed from "" to
317 "target:". "remote:" is automatically converted to "target:" for
318 backward compatibility.
320 * The system root specified by "set sysroot" will be prepended to the
321 filename of the main executable (if reported to GDB as absolute by
322 the operating system) when starting processes remotely, and when
323 attaching to already-running local or remote processes.
325 * GDB now supports automatic location and retrieval of executable
326 files from remote targets. Remote debugging can now be initiated
327 using only a "target remote" or "target extended-remote" command
328 (no "set sysroot" or "file" commands are required). See "New remote
331 * The "dump" command now supports verilog hex format.
333 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
335 * On GNU/Linux, GDB and gdbserver are now able to access executable
336 and shared library files without a "set sysroot" command when
337 attaching to processes running in different mount namespaces from
338 the debugger. This makes it possible to attach to processes in
339 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
340 See "New remote packets" below.
342 * The "tui reg" command now provides completion for all of the
343 available register groups, including target specific groups.
345 * The HISTSIZE environment variable is no longer read when determining
346 the size of GDB's command history. GDB now instead reads the dedicated
347 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
348 disables truncation of command history. Non-numeric values of GDBHISTSIZE
353 ** Memory ports can now be unbuffered.
357 ** gdb.Objfile objects have a new attribute "username",
358 which is the name of the objfile as specified by the user,
359 without, for example, resolving symlinks.
360 ** You can now write frame unwinders in Python.
361 ** gdb.Type objects have a new method "optimized_out",
362 returning optimized out gdb.Value instance of this type.
363 ** gdb.Value objects have new methods "reference_value" and
364 "const_value" which return a reference to the value and a
365 "const" version of the value respectively.
369 maint print symbol-cache
370 Print the contents of the symbol cache.
372 maint print symbol-cache-statistics
373 Print statistics of symbol cache usage.
375 maint flush-symbol-cache
376 Flush the contents of the symbol cache.
380 Start branch trace recording using Branch Trace Store (BTS) format.
383 Evaluate expression by using the compiler and print result.
387 Explicit commands for enabling and disabling tui mode.
390 set mpx bound on i386 and amd64
391 Support for bound table investigation on Intel MPX enabled applications.
395 Start branch trace recording using Intel Processor Trace format.
398 Print information about branch tracing internals.
400 maint btrace packet-history
401 Print the raw branch tracing data.
403 maint btrace clear-packet-history
404 Discard the stored raw branch tracing data.
407 Discard all branch tracing data. It will be fetched and processed
408 anew by the next "record" command.
413 Renamed from "set debug dwarf2-die".
415 Renamed from "show debug dwarf2-die".
418 Renamed from "set debug dwarf2-read".
419 show debug dwarf-read
420 Renamed from "show debug dwarf2-read".
422 maint set dwarf always-disassemble
423 Renamed from "maint set dwarf2 always-disassemble".
424 maint show dwarf always-disassemble
425 Renamed from "maint show dwarf2 always-disassemble".
427 maint set dwarf max-cache-age
428 Renamed from "maint set dwarf2 max-cache-age".
429 maint show dwarf max-cache-age
430 Renamed from "maint show dwarf2 max-cache-age".
433 show debug dwarf-line
434 Control display of debugging info regarding DWARF line processing.
438 Set the maximum number of candidates to be considered during
439 completion. The default value is 200. This limit allows GDB
440 to avoid generating large completion lists, the computation of
441 which can cause the debugger to become temporarily unresponsive.
443 set history remove-duplicates
444 show history remove-duplicates
445 Control the removal of duplicate history entries.
447 maint set symbol-cache-size
448 maint show symbol-cache-size
449 Control the size of the symbol cache.
451 set|show record btrace bts buffer-size
452 Set and show the size of the ring buffer used for branch tracing in
454 The obtained size may differ from the requested size. Use "info
455 record" to see the obtained buffer size.
457 set debug linux-namespaces
458 show debug linux-namespaces
459 Control display of debugging info regarding Linux namespaces.
461 set|show record btrace pt buffer-size
462 Set and show the size of the ring buffer used for branch tracing in
463 Intel Processor Trace format.
464 The obtained size may differ from the requested size. Use "info
465 record" to see the obtained buffer size.
467 maint set|show btrace pt skip-pad
468 Set and show whether PAD packets are skipped when computing the
471 * The command 'thread apply all' can now support new option '-ascending'
472 to call its specified command for all threads in ascending order.
474 * Python/Guile scripting
476 ** GDB now supports auto-loading of Python/Guile scripts contained in the
477 special section named `.debug_gdb_scripts'.
481 qXfer:btrace-conf:read
482 Return the branch trace configuration for the current thread.
484 Qbtrace-conf:bts:size
485 Set the requested ring buffer size for branch tracing in BTS format.
488 Enable Intel Procesor Trace-based branch tracing for the current
489 process. The remote stub reports support for this packet to GDB's
493 Set the requested ring buffer size for branch tracing in Intel Processor
497 Indicates a memory breakpoint instruction was executed, irrespective
498 of whether it was GDB that planted the breakpoint or the breakpoint
499 is hardcoded in the program. This is required for correct non-stop
503 Indicates the target stopped for a hardware breakpoint. This is
504 required for correct non-stop mode operation.
507 Return information about files on the remote system.
510 Return the full absolute name of the file that was executed to
511 create a process running on the remote system.
514 Select the filesystem on which vFile: operations with filename
515 arguments will operate. This is required for GDB to be able to
516 access files on remote targets where the remote stub does not
517 share a common filesystem with the inferior(s).
520 Indicates that a fork system call was executed.
523 Indicates that a vfork system call was executed.
525 vforkdone stop reason
526 Indicates that a vfork child of the specified process has executed
527 an exec or exit, allowing the vfork parent to resume execution.
529 fork-events and vfork-events features in qSupported
530 The qSupported packet allows GDB to request support for fork and
531 vfork events using new 'gdbfeatures' fork-events and vfork-events,
532 and the qSupported response can contain the corresponding
533 'stubfeatures'. Set and show commands can be used to display
534 whether these features are enabled.
536 * Extended-remote fork events
538 ** GDB now has support for fork events on extended-remote Linux
539 targets. For targets with Linux kernels 2.5.60 and later, this
540 enables follow-fork-mode and detach-on-fork for both fork and
541 vfork, as well as fork and vfork catchpoints.
543 * The info record command now shows the recording format and the
544 branch tracing configuration for the current thread when using
545 the btrace record target.
546 For the BTS format, it shows the ring buffer size.
548 * GDB now has support for DTrace USDT (Userland Static Defined
549 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
551 * GDB now supports access to vector registers on S/390 GNU/Linux
554 * Removed command line options
556 -xdb HP-UX XDB compatibility mode.
558 * Removed targets and native configurations
560 HP/PA running HP-UX hppa*-*-hpux*
561 Itanium running HP-UX ia64-*-hpux*
563 * New configure options
566 This configure option allows the user to build GDB with support for
567 Intel Processor Trace (default: auto). This requires libipt.
569 --with-libipt-prefix=PATH
570 Specify the path to the version of libipt that GDB should use.
571 $PATH/include should contain the intel-pt.h header and
572 $PATH/lib should contain the libipt.so library.
574 *** Changes in GDB 7.9.1
578 ** Xmethods can now specify a result type.
580 *** Changes in GDB 7.9
582 * GDB now supports hardware watchpoints on x86 GNU Hurd.
586 ** You can now access frame registers from Python scripts.
587 ** New attribute 'producer' for gdb.Symtab objects.
588 ** gdb.Objfile objects have a new attribute "progspace",
589 which is the gdb.Progspace object of the containing program space.
590 ** gdb.Objfile objects have a new attribute "owner".
591 ** gdb.Objfile objects have a new attribute "build_id",
592 which is the build ID generated when the file was built.
593 ** gdb.Objfile objects have a new method "add_separate_debug_file".
594 ** A new event "gdb.clear_objfiles" has been added, triggered when
595 selecting a new file to debug.
596 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
597 ** New function gdb.lookup_objfile.
599 New events which are triggered when GDB modifies the state of the
602 ** gdb.events.inferior_call_pre: Function call is about to be made.
603 ** gdb.events.inferior_call_post: Function call has just been made.
604 ** gdb.events.memory_changed: A memory location has been altered.
605 ** gdb.events.register_changed: A register has been altered.
607 * New Python-based convenience functions:
609 ** $_caller_is(name [, number_of_frames])
610 ** $_caller_matches(regexp [, number_of_frames])
611 ** $_any_caller_is(name [, number_of_frames])
612 ** $_any_caller_matches(regexp [, number_of_frames])
614 * GDB now supports the compilation and injection of source code into
615 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
616 to compile the source code to object code, and if successful, inject
617 and execute that code within the current context of the inferior.
618 Currently the C language is supported. The commands used to
619 interface with this new feature are:
621 compile code [-raw|-r] [--] [source code]
622 compile file [-raw|-r] filename
626 demangle [-l language] [--] name
627 Demangle "name" in the specified language, or the current language
628 if elided. This command is renamed from the "maint demangle" command.
629 The latter is kept as a no-op to avoid "maint demangle" being interpreted
630 as "maint demangler-warning".
632 queue-signal signal-name-or-number
633 Queue a signal to be delivered to the thread when it is resumed.
635 add-auto-load-scripts-directory directory
636 Add entries to the list of directories from which to load auto-loaded
639 maint print user-registers
640 List all currently available "user" registers.
642 compile code [-r|-raw] [--] [source code]
643 Compile, inject, and execute in the inferior the executable object
644 code produced by compiling the provided source code.
646 compile file [-r|-raw] filename
647 Compile and inject into the inferior the executable object code
648 produced by compiling the source code stored in the filename
651 * On resume, GDB now always passes the signal the program had stopped
652 for to the thread the signal was sent to, even if the user changed
653 threads before resuming. Previously GDB would often (but not
654 always) deliver the signal to the thread that happens to be current
657 * Conversely, the "signal" command now consistently delivers the
658 requested signal to the current thread. GDB now asks for
659 confirmation if the program had stopped for a signal and the user
660 switched threads meanwhile.
662 * "breakpoint always-inserted" modes "off" and "auto" merged.
664 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
665 won't remove breakpoints from the target until all threads stop,
666 even in non-stop mode. The "auto" mode has been removed, and "off"
667 is now the default mode.
671 set debug symbol-lookup
672 show debug symbol-lookup
673 Control display of debugging info regarding symbol lookup.
677 ** The -list-thread-groups command outputs an exit-code field for
678 inferiors that have exited.
682 MIPS SDE mips*-sde*-elf*
686 Support for these obsolete configurations has been removed.
688 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
689 SGI Irix-5.x mips-*-irix5*
690 SGI Irix-6.x mips-*-irix6*
691 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
692 VAX running Ultrix vax-*-ultrix*
694 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
695 and "assf"), have been removed. Use the "sharedlibrary" command, or
696 its alias "share", instead.
698 *** Changes in GDB 7.8
700 * New command line options
703 This is an alias for the --data-directory option.
705 * GDB supports printing and modifying of variable length automatic arrays
706 as specified in ISO C99.
708 * The ARM simulator now supports instruction level tracing
709 with or without disassembly.
713 GDB now has support for scripting using Guile. Whether this is
714 available is determined at configure time.
715 Guile version 2.0 or greater is required.
716 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
718 * New commands (for set/show, see "New options" below)
722 Invoke CODE by passing it to the Guile interpreter.
726 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
728 info auto-load guile-scripts [regexp]
729 Print the list of automatically loaded Guile scripts.
731 * The source command is now capable of sourcing Guile scripts.
732 This feature is dependent on the debugger being built with Guile support.
736 set print symbol-loading (off|brief|full)
737 show print symbol-loading
738 Control whether to print informational messages when loading symbol
739 information for a file. The default is "full", but when debugging
740 programs with large numbers of shared libraries the amount of output
743 set guile print-stack (none|message|full)
744 show guile print-stack
745 Show a stack trace when an error is encountered in a Guile script.
747 set auto-load guile-scripts (on|off)
748 show auto-load guile-scripts
749 Control auto-loading of Guile script files.
751 maint ada set ignore-descriptive-types (on|off)
752 maint ada show ignore-descriptive-types
753 Control whether the debugger should ignore descriptive types in Ada
754 programs. The default is not to ignore the descriptive types. See
755 the user manual for more details on descriptive types and the intended
756 usage of this option.
758 set auto-connect-native-target
760 Control whether GDB is allowed to automatically connect to the
761 native target for the run, attach, etc. commands when not connected
762 to any target yet. See also "target native" below.
764 set record btrace replay-memory-access (read-only|read-write)
765 show record btrace replay-memory-access
766 Control what memory accesses are allowed during replay.
768 maint set target-async (on|off)
769 maint show target-async
770 This controls whether GDB targets operate in synchronous or
771 asynchronous mode. Normally the default is asynchronous, if it is
772 available; but this can be changed to more easily debug problems
773 occurring only in synchronous mode.
775 set mi-async (on|off)
777 Control whether MI asynchronous mode is preferred. This supersedes
778 "set target-async" of previous GDB versions.
780 * "set target-async" is deprecated as a CLI option and is now an alias
781 for "set mi-async" (only puts MI into async mode).
783 * Background execution commands (e.g., "c&", "s&", etc.) are now
784 possible ``out of the box'' if the target supports them. Previously
785 the user would need to explicitly enable the possibility with the
786 "set target-async on" command.
788 * New features in the GDB remote stub, GDBserver
790 ** New option --debug-format=option1[,option2,...] allows one to add
791 additional text to each output. At present only timestamps
792 are supported: --debug-format=timestamps.
793 Timestamps can also be turned on with the
794 "monitor set debug-format timestamps" command from GDB.
796 * The 'record instruction-history' command now starts counting instructions
797 at one. This also affects the instruction ranges reported by the
798 'record function-call-history' command when given the /i modifier.
800 * The command 'record function-call-history' supports a new modifier '/c' to
801 indent the function names based on their call stack depth.
802 The fields for the '/i' and '/l' modifier have been reordered.
803 The source line range is now prefixed with 'at'.
804 The instruction range is now prefixed with 'inst'.
805 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
806 "record instruction-history" and "list" commands.
808 * The ranges given as arguments to the 'record function-call-history' and
809 'record instruction-history' commands are now inclusive.
811 * The btrace record target now supports the 'record goto' command.
812 For locations inside the execution trace, the back trace is computed
813 based on the information stored in the execution trace.
815 * The btrace record target supports limited reverse execution and replay.
816 The target does not record data and therefore does not allow reading
819 * The "catch syscall" command now works on s390*-linux* targets.
821 * The "compare-sections" command is no longer specific to target
822 remote. It now works with all targets.
824 * All native targets are now consistently called "native".
825 Consequently, the "target child", "target GNU", "target djgpp",
826 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
827 commands have been replaced with "target native". The QNX/NTO port
828 leaves the "procfs" target in place and adds a "native" target for
829 consistency with other ports. The impact on users should be minimal
830 as these commands previously either throwed an error, or were
831 no-ops. The target's name is visible in the output of the following
832 commands: "help target", "info target", "info files", "maint print
835 * The "target native" command now connects to the native target. This
836 can be used to launch native programs even when "set
837 auto-connect-native-target" is set to off.
839 * GDB now supports access to Intel MPX registers on GNU/Linux.
841 * Support for Intel AVX-512 registers on GNU/Linux.
842 Support displaying and modifying Intel AVX-512 registers
843 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
847 qXfer:btrace:read's annex
848 The qXfer:btrace:read packet supports a new annex 'delta' to read
849 branch trace incrementally.
853 ** Valid Python operations on gdb.Value objects representing
854 structs/classes invoke the corresponding overloaded operators if
856 ** New `Xmethods' feature in the Python API. Xmethods are
857 additional methods or replacements for existing methods of a C++
858 class. This feature is useful for those cases where a method
859 defined in C++ source code could be inlined or optimized out by
860 the compiler, making it unavailable to GDB.
863 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
865 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
866 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
867 its alias "share", instead.
869 * The commands "set remotebaud" and "show remotebaud" are no longer
870 supported. Use "set serial baud" and "show serial baud" (respectively)
875 ** A new option "-gdb-set mi-async" replaces "-gdb-set
876 target-async". The latter is left as a deprecated alias of the
877 former for backward compatibility. If the target supports it,
878 CLI background execution commands are now always possible by
879 default, independently of whether the frontend stated a
880 preference for asynchronous execution with "-gdb-set mi-async".
881 Previously "-gdb-set target-async off" affected both MI execution
882 commands and CLI execution commands.
884 *** Changes in GDB 7.7
886 * Improved support for process record-replay and reverse debugging on
887 arm*-linux* targets. Support for thumb32 and syscall instruction
888 recording has been added.
890 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
892 * GDB now supports Fission DWP file format version 2.
893 http://gcc.gnu.org/wiki/DebugFission
895 * New convenience function "$_isvoid", to check whether an expression
896 is void. A void expression is an expression where the type of the
897 result is "void". For example, some convenience variables may be
898 "void" when evaluated (e.g., "$_exitcode" before the execution of
899 the program being debugged; or an undefined convenience variable).
900 Another example, when calling a function whose return type is
903 * The "maintenance print objfiles" command now takes an optional regexp.
905 * The "catch syscall" command now works on arm*-linux* targets.
907 * GDB now consistently shows "<not saved>" when printing values of
908 registers the debug info indicates have not been saved in the frame
909 and there's nowhere to retrieve them from
910 (callee-saved/call-clobbered registers):
915 (gdb) info registers rax
918 Before, the former would print "<optimized out>", and the latter
919 "*value not available*".
921 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
926 ** Frame filters and frame decorators have been added.
927 ** Temporary breakpoints are now supported.
928 ** Line tables representation has been added.
929 ** New attribute 'parent_type' for gdb.Field objects.
930 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
931 ** New attribute 'name' for gdb.Type objects.
935 Nios II ELF nios2*-*-elf
936 Nios II GNU/Linux nios2*-*-linux
937 Texas Instruments MSP430 msp430*-*-elf
939 * Removed native configurations
941 Support for these a.out NetBSD and OpenBSD obsolete configurations has
942 been removed. ELF variants of these configurations are kept supported.
944 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
945 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
946 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
947 i[34567]86-*-openbsd3.[0-3]
948 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
949 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
950 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
954 Like "catch throw", but catches a re-thrown exception.
956 Renamed from old "maint check-symtabs".
958 Perform consistency checks on symtabs.
960 Expand symtabs matching an optional regexp.
963 Display the details of GDB configure-time options.
965 maint set|show per-command
966 maint set|show per-command space
967 maint set|show per-command time
968 maint set|show per-command symtab
969 Enable display of per-command gdb resource usage.
971 remove-symbol-file FILENAME
972 remove-symbol-file -a ADDRESS
973 Remove a symbol file added via add-symbol-file. The file to remove
974 can be identified by its filename or by an address that lies within
975 the boundaries of this symbol file in memory.
978 info exceptions REGEXP
979 Display the list of Ada exceptions defined in the program being
980 debugged. If provided, only the exceptions whose names match REGEXP
985 set debug symfile off|on
987 Control display of debugging info regarding reading symbol files and
988 symbol tables within those files
990 set print raw frame-arguments
991 show print raw frame-arguments
992 Set/show whether to print frame arguments in raw mode,
993 disregarding any defined pretty-printers.
995 set remote trace-status-packet
996 show remote trace-status-packet
997 Set/show the use of remote protocol qTStatus packet.
1001 Control display of debugging messages related to Nios II targets.
1005 Control whether target-assisted range stepping is enabled.
1007 set startup-with-shell
1008 show startup-with-shell
1009 Specifies whether Unix child processes are started via a shell or
1014 Use the target memory cache for accesses to the code segment. This
1015 improves performance of remote debugging (particularly disassembly).
1017 * You can now use a literal value 'unlimited' for options that
1018 interpret 0 or -1 as meaning "unlimited". E.g., "set
1019 trace-buffer-size unlimited" is now an alias for "set
1020 trace-buffer-size -1" and "set height unlimited" is now an alias for
1023 * The "set debug symtab-create" debugging option of GDB has been changed to
1024 accept a verbosity level. 0 means "off", 1 provides basic debugging
1025 output, and values of 2 or greater provides more verbose output.
1027 * New command-line options
1029 Display the details of GDB configure-time options.
1031 * The command 'tsave' can now support new option '-ctf' to save trace
1032 buffer in Common Trace Format.
1034 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1037 * GDB now implements the the C++ 'typeid' operator.
1039 * The new convenience variable $_exception holds the exception being
1040 thrown or caught at an exception-related catchpoint.
1042 * The exception-related catchpoints, like "catch throw", now accept a
1043 regular expression which can be used to filter exceptions by type.
1045 * The new convenience variable $_exitsignal is automatically set to
1046 the terminating signal number when the program being debugged dies
1047 due to an uncaught signal.
1051 ** All MI commands now accept an optional "--language" option.
1052 Support for this feature can be verified by using the "-list-features"
1053 command, which should contain "language-option".
1055 ** The new command -info-gdb-mi-command allows the user to determine
1056 whether a GDB/MI command is supported or not.
1058 ** The "^error" result record returned when trying to execute an undefined
1059 GDB/MI command now provides a variable named "code" whose content is the
1060 "undefined-command" error code. Support for this feature can be verified
1061 by using the "-list-features" command, which should contain
1062 "undefined-command-error-code".
1064 ** The -trace-save MI command can optionally save trace buffer in Common
1067 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1069 ** The command -data-list-register-values now accepts an optional
1070 "--skip-unavailable" option. When used, only the available registers
1073 ** The new command -trace-frame-collected dumps collected variables,
1074 computed expressions, tvars, memory and registers in a traceframe.
1076 ** The commands -stack-list-locals, -stack-list-arguments and
1077 -stack-list-variables now accept an option "--skip-unavailable".
1078 When used, only the available locals or arguments are displayed.
1080 ** The -exec-run command now accepts an optional "--start" option.
1081 When used, the command follows the same semantics as the "start"
1082 command, stopping the program's execution at the start of its
1083 main subprogram. Support for this feature can be verified using
1084 the "-list-features" command, which should contain
1085 "exec-run-start-option".
1087 ** The new commands -catch-assert and -catch-exceptions insert
1088 catchpoints stopping the program when Ada exceptions are raised.
1090 ** The new command -info-ada-exceptions provides the equivalent of
1091 the new "info exceptions" command.
1093 * New system-wide configuration scripts
1094 A GDB installation now provides scripts suitable for use as system-wide
1095 configuration scripts for the following systems:
1099 * GDB now supports target-assigned range stepping with remote targets.
1100 This improves the performance of stepping source lines by reducing
1101 the number of control packets from/to GDB. See "New remote packets"
1104 * GDB now understands the element 'tvar' in the XML traceframe info.
1105 It has the id of the collected trace state variables.
1107 * On S/390 targets that provide the transactional-execution feature,
1108 the program interruption transaction diagnostic block (TDB) is now
1109 represented as a number of additional "registers" in GDB.
1111 * New remote packets
1115 The vCont packet supports a new 'r' action, that tells the remote
1116 stub to step through an address range itself, without GDB
1117 involvemement at each single-step.
1119 qXfer:libraries-svr4:read's annex
1120 The previously unused annex of the qXfer:libraries-svr4:read packet
1121 is now used to support passing an argument list. The remote stub
1122 reports support for this argument list to GDB's qSupported query.
1123 The defined arguments are "start" and "prev", used to reduce work
1124 necessary for library list updating, resulting in significant
1127 * New features in the GDB remote stub, GDBserver
1129 ** GDBserver now supports target-assisted range stepping. Currently
1130 enabled on x86/x86_64 GNU/Linux targets.
1132 ** GDBserver now adds element 'tvar' in the XML in the reply to
1133 'qXfer:traceframe-info:read'. It has the id of the collected
1134 trace state variables.
1136 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1139 * New 'z' formatter for printing and examining memory, this displays the
1140 value as hexadecimal zero padded on the left to the size of the type.
1142 * GDB can now use Windows x64 unwinding data.
1144 * The "set remotebaud" command has been replaced by "set serial baud".
1145 Similarly, "show remotebaud" has been replaced by "show serial baud".
1146 The "set remotebaud" and "show remotebaud" commands are still available
1147 to provide backward compatibility with older versions of GDB.
1149 *** Changes in GDB 7.6
1151 * Target record has been renamed to record-full.
1152 Record/replay is now enabled with the "record full" command.
1153 This also affects settings that are associated with full record/replay
1154 that have been moved from "set/show record" to "set/show record full":
1156 set|show record full insn-number-max
1157 set|show record full stop-at-limit
1158 set|show record full memory-query
1160 * A new record target "record-btrace" has been added. The new target
1161 uses hardware support to record the control-flow of a process. It
1162 does not support replaying the execution, but it implements the
1163 below new commands for investigating the recorded execution log.
1164 This new recording method can be enabled using:
1168 The "record-btrace" target is only available on Intel Atom processors
1169 and requires a Linux kernel 2.6.32 or later.
1171 * Two new commands have been added for record/replay to give information
1172 about the recorded execution without having to replay the execution.
1173 The commands are only supported by "record btrace".
1175 record instruction-history prints the execution history at
1176 instruction granularity
1178 record function-call-history prints the execution history at
1179 function granularity
1181 * New native configurations
1183 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1184 FreeBSD/powerpc powerpc*-*-freebsd
1185 x86_64/Cygwin x86_64-*-cygwin*
1186 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1190 ARM AArch64 aarch64*-*-elf
1191 ARM AArch64 GNU/Linux aarch64*-*-linux
1192 Lynx 178 PowerPC powerpc-*-lynx*178
1193 x86_64/Cygwin x86_64-*-cygwin*
1194 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1196 * If the configured location of system.gdbinit file (as given by the
1197 --with-system-gdbinit option at configure time) is in the
1198 data-directory (as specified by --with-gdb-datadir at configure
1199 time) or in one of its subdirectories, then GDB will look for the
1200 system-wide init file in the directory specified by the
1201 --data-directory command-line option.
1203 * New command line options:
1205 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1206 other initialization files, unlike -nx which disables all of them.
1208 * Removed command line options
1210 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1213 * The 'ptype' and 'whatis' commands now accept an argument to control
1216 * 'info proc' now works on some core files.
1220 ** Vectors can be created with gdb.Type.vector.
1222 ** Python's atexit.register now works in GDB.
1224 ** Types can be pretty-printed via a Python API.
1226 ** Python 3 is now supported (in addition to Python 2.4 or later)
1228 ** New class gdb.Architecture exposes GDB's internal representation
1229 of architecture in the Python API.
1231 ** New method Frame.architecture returns the gdb.Architecture object
1232 corresponding to the frame's architecture.
1234 * New Python-based convenience functions:
1236 ** $_memeq(buf1, buf2, length)
1237 ** $_streq(str1, str2)
1239 ** $_regex(str, regex)
1241 * The 'cd' command now defaults to using '~' (the home directory) if not
1244 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1245 default for GCC since November 2000.
1247 * The command 'forward-search' can now be abbreviated as 'fo'.
1249 * The command 'info tracepoints' can now display 'installed on target'
1250 or 'not installed on target' for each non-pending location of tracepoint.
1252 * New configure options
1254 --enable-libmcheck/--disable-libmcheck
1255 By default, development versions are built with -lmcheck on hosts
1256 that support it, in order to help track memory corruption issues.
1257 Release versions, on the other hand, are built without -lmcheck
1258 by default. The --enable-libmcheck/--disable-libmcheck configure
1259 options allow the user to override that default.
1260 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1261 This configure option allows the user to build GDB with
1262 libbabeltrace using which GDB can read Common Trace Format data.
1264 * New commands (for set/show, see "New options" below)
1267 Catch signals. This is similar to "handle", but allows commands and
1268 conditions to be attached.
1271 List the BFDs known to GDB.
1273 python-interactive [command]
1275 Start a Python interactive prompt, or evaluate the optional command
1276 and print the result of expressions.
1279 "py" is a new alias for "python".
1281 enable type-printer [name]...
1282 disable type-printer [name]...
1283 Enable or disable type printers.
1287 ** For the Renesas Super-H architecture, the "regs" command has been removed
1288 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1293 set print type methods (on|off)
1294 show print type methods
1295 Control whether method declarations are displayed by "ptype".
1296 The default is to show them.
1298 set print type typedefs (on|off)
1299 show print type typedefs
1300 Control whether typedef definitions are displayed by "ptype".
1301 The default is to show them.
1303 set filename-display basename|relative|absolute
1304 show filename-display
1305 Control the way in which filenames is displayed.
1306 The default is "relative", which preserves previous behavior.
1308 set trace-buffer-size
1309 show trace-buffer-size
1310 Request target to change the size of trace buffer.
1312 set remote trace-buffer-size-packet auto|on|off
1313 show remote trace-buffer-size-packet
1314 Control the use of the remote protocol `QTBuffer:size' packet.
1318 Control display of debugging messages related to ARM AArch64.
1321 set debug coff-pe-read
1322 show debug coff-pe-read
1323 Control display of debugging messages related to reading of COFF/PE
1328 Control display of debugging messages related to Mach-O symbols
1331 set debug notification
1332 show debug notification
1333 Control display of debugging info for async remote notification.
1337 ** Command parameter changes are now notified using new async record
1338 "=cmd-param-changed".
1339 ** Trace frame changes caused by command "tfind" are now notified using
1340 new async record "=traceframe-changed".
1341 ** The creation, deletion and modification of trace state variables
1342 are now notified using new async records "=tsv-created",
1343 "=tsv-deleted" and "=tsv-modified".
1344 ** The start and stop of process record are now notified using new
1345 async record "=record-started" and "=record-stopped".
1346 ** Memory changes are now notified using new async record
1348 ** The data-disassemble command response will include a "fullname" field
1349 containing the absolute file name when source has been requested.
1350 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1351 command, to allow pattern filling of memory areas.
1352 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1353 library load/unload events.
1354 ** The response to breakpoint commands and breakpoint async records
1355 includes an "installed" field containing a boolean state about each
1356 non-pending tracepoint location is whether installed on target or not.
1357 ** Output of the "-trace-status" command includes a "trace-file" field
1358 containing the name of the trace file being examined. This field is
1359 optional, and only present when examining a trace file.
1360 ** The "fullname" field is now always present along with the "file" field,
1361 even if the file cannot be found by GDB.
1363 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1364 You must have the LZMA library available when configuring GDB for this
1365 feature to be enabled. For more information, see:
1366 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1368 * New remote packets
1371 Set the size of trace buffer. The remote stub reports support for this
1372 packet to gdb's qSupported query.
1375 Enable Branch Trace Store (BTS)-based branch tracing for the current
1376 thread. The remote stub reports support for this packet to gdb's
1380 Disable branch tracing for the current thread. The remote stub reports
1381 support for this packet to gdb's qSupported query.
1384 Read the traced branches for the current thread. The remote stub
1385 reports support for this packet to gdb's qSupported query.
1387 *** Changes in GDB 7.5
1389 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1390 for more x32 ABI info.
1392 * GDB now supports access to MIPS DSP registers on Linux targets.
1394 * GDB now supports debugging microMIPS binaries.
1396 * The "info os" command on GNU/Linux can now display information on
1397 several new classes of objects managed by the operating system:
1398 "info os procgroups" lists process groups
1399 "info os files" lists file descriptors
1400 "info os sockets" lists internet-domain sockets
1401 "info os shm" lists shared-memory regions
1402 "info os semaphores" lists semaphores
1403 "info os msg" lists message queues
1404 "info os modules" lists loaded kernel modules
1406 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1407 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1408 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1409 options and inspect the probe arguments using the new $_probe_arg family
1410 of convenience variables. You can obtain more information about SystemTap
1411 in <http://sourceware.org/systemtap/>.
1413 * GDB now supports reversible debugging on ARM, it allows you to
1414 debug basic ARM and THUMB instructions, and provides
1415 record/replay support.
1417 * The option "symbol-reloading" has been deleted as it is no longer used.
1421 ** GDB commands implemented in Python can now be put in command class
1424 ** The "maint set python print-stack on|off" is now deleted.
1426 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1427 apply "flag enum"-style pretty-printing to any enum.
1429 ** gdb.lookup_symbol can now work when there is no current frame.
1431 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1432 the source at which the symbol was defined.
1434 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1435 method 'value'. The former indicates whether the symbol needs a
1436 frame in order to compute its value, and the latter computes the
1439 ** A new method 'referenced_value' on gdb.Value objects which can
1440 dereference pointer as well as C++ reference values.
1442 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1443 which return the global and static blocks (as gdb.Block objects),
1444 of the underlying symbol table, respectively.
1446 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1447 object associated with a PC value.
1449 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1450 of the address range occupied by code for the current source line.
1452 * Go language support.
1453 GDB now supports debugging programs written in the Go programming
1456 * GDBserver now supports stdio connections.
1457 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1459 * The binary "gdbtui" can no longer be built or installed.
1460 Use "gdb -tui" instead.
1462 * GDB will now print "flag" enums specially. A flag enum is one where
1463 all the enumerator values have no bits in common when pairwise
1464 "and"ed. When printing a value whose type is a flag enum, GDB will
1465 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1466 (gdb) print (enum E) 3
1469 * The filename part of a linespec will now match trailing components
1470 of a source file name. For example, "break gcc/expr.c:1000" will
1471 now set a breakpoint in build/gcc/expr.c, but not
1472 build/libcpp/expr.c.
1474 * The "info proc" and "generate-core-file" commands will now also
1475 work on remote targets connected to GDBserver on Linux.
1477 * The command "info catch" has been removed. It has been disabled
1478 since December 2007.
1480 * The "catch exception" and "catch assert" commands now accept
1481 a condition at the end of the command, much like the "break"
1482 command does. For instance:
1484 (gdb) catch exception Constraint_Error if Barrier = True
1486 Previously, it was possible to add a condition to such catchpoints,
1487 but it had to be done as a second step, after the catchpoint had been
1488 created, using the "condition" command.
1490 * The "info static-tracepoint-marker" command will now also work on
1491 native Linux targets with in-process agent.
1493 * GDB can now set breakpoints on inlined functions.
1495 * The .gdb_index section has been updated to include symbols for
1496 inlined functions. GDB will ignore older .gdb_index sections by
1497 default, which could cause symbol files to be loaded more slowly
1498 until their .gdb_index sections can be recreated. The new command
1499 "set use-deprecated-index-sections on" will cause GDB to use any older
1500 .gdb_index sections it finds. This will restore performance, but the
1501 ability to set breakpoints on inlined functions will be lost in symbol
1502 files with older .gdb_index sections.
1504 The .gdb_index section has also been updated to record more information
1505 about each symbol. This speeds up the "info variables", "info functions"
1506 and "info types" commands when used with programs having the .gdb_index
1507 section, as well as speeding up debugging with shared libraries using
1508 the .gdb_index section.
1510 * Ada support for GDB/MI Variable Objects has been added.
1512 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1517 ** New command -info-os is the MI equivalent of "info os".
1519 ** Output logs ("set logging" and related) now include MI output.
1523 ** "set use-deprecated-index-sections on|off"
1524 "show use-deprecated-index-sections on|off"
1525 Controls the use of deprecated .gdb_index sections.
1527 ** "catch load" and "catch unload" can be used to stop when a shared
1528 library is loaded or unloaded, respectively.
1530 ** "enable count" can be used to auto-disable a breakpoint after
1533 ** "info vtbl" can be used to show the virtual method tables for
1534 C++ and Java objects.
1536 ** "explore" and its sub commands "explore value" and "explore type"
1537 can be used to recursively explore values and types of
1538 expressions. These commands are available only if GDB is
1539 configured with '--with-python'.
1541 ** "info auto-load" shows status of all kinds of auto-loaded files,
1542 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1543 sequences of commands files, "info auto-load python-scripts"
1544 shows status of auto-loading Python script files,
1545 "info auto-load local-gdbinit" shows status of loading init file
1546 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1547 status of inferior specific thread debugging shared library loading.
1549 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1550 and "show auto-load-scripts" commands have been deprecated, use their
1551 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1552 and "show auto-load python-scripts" counterparts instead.
1554 ** "dprintf location,format,args..." creates a dynamic printf, which
1555 is basically a breakpoint that does a printf and immediately
1556 resumes your program's execution, so it is like a printf that you
1557 can insert dynamically at runtime instead of at compiletime.
1559 ** "set print symbol"
1561 Controls whether GDB attempts to display the symbol, if any,
1562 corresponding to addresses it prints. This defaults to "on", but
1563 you can set it to "off" to restore GDB's previous behavior.
1565 * Deprecated commands
1567 ** For the Renesas Super-H architecture, the "regs" command has been
1568 deprecated, and "info all-registers" should be used instead.
1572 Renesas RL78 rl78-*-elf
1573 HP OpenVMS ia64 ia64-hp-openvms*
1575 * GDBserver supports evaluation of breakpoint conditions. When
1576 support is advertised by GDBserver, GDB may be told to send the
1577 breakpoint conditions in bytecode form to GDBserver. GDBserver
1578 will only report the breakpoint trigger to GDB when its condition
1583 set mips compression
1584 show mips compression
1585 Select the compressed ISA encoding used in functions that have no symbol
1586 information available. The encoding can be set to either of:
1589 and is updated automatically from ELF file flags if available.
1591 set breakpoint condition-evaluation
1592 show breakpoint condition-evaluation
1593 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1594 GDBserver ("target"). Default option "auto" chooses the most efficient
1596 This option can improve debugger efficiency depending on the speed of the
1600 Disable auto-loading globally.
1603 Show auto-loading setting of all kinds of auto-loaded files.
1605 set auto-load gdb-scripts on|off
1606 show auto-load gdb-scripts
1607 Control auto-loading of GDB canned sequences of commands files.
1609 set auto-load python-scripts on|off
1610 show auto-load python-scripts
1611 Control auto-loading of Python script files.
1613 set auto-load local-gdbinit on|off
1614 show auto-load local-gdbinit
1615 Control loading of init file (.gdbinit) from current directory.
1617 set auto-load libthread-db on|off
1618 show auto-load libthread-db
1619 Control auto-loading of inferior specific thread debugging shared library.
1621 set auto-load scripts-directory <dir1>[:<dir2>...]
1622 show auto-load scripts-directory
1623 Set a list of directories from which to load auto-loaded scripts.
1624 Automatically loaded Python scripts and GDB scripts are located in one
1625 of the directories listed by this option.
1626 The delimiter (':' above) may differ according to the host platform.
1628 set auto-load safe-path <dir1>[:<dir2>...]
1629 show auto-load safe-path
1630 Set a list of directories from which it is safe to auto-load files.
1631 The delimiter (':' above) may differ according to the host platform.
1633 set debug auto-load on|off
1634 show debug auto-load
1635 Control display of debugging info for auto-loading the files above.
1637 set dprintf-style gdb|call|agent
1639 Control the way in which a dynamic printf is performed; "gdb"
1640 requests a GDB printf command, while "call" causes dprintf to call a
1641 function in the inferior. "agent" requests that the target agent
1642 (such as GDBserver) do the printing.
1644 set dprintf-function <expr>
1645 show dprintf-function
1646 set dprintf-channel <expr>
1647 show dprintf-channel
1648 Set the function and optional first argument to the call when using
1649 the "call" style of dynamic printf.
1651 set disconnected-dprintf on|off
1652 show disconnected-dprintf
1653 Control whether agent-style dynamic printfs continue to be in effect
1654 after GDB disconnects.
1656 * New configure options
1658 --with-auto-load-dir
1659 Configure default value for the 'set auto-load scripts-directory'
1660 setting above. It defaults to '$debugdir:$datadir/auto-load',
1661 $debugdir representing global debugging info directories (available
1662 via 'show debug-file-directory') and $datadir representing GDB's data
1663 directory (available via 'show data-directory').
1665 --with-auto-load-safe-path
1666 Configure default value for the 'set auto-load safe-path' setting
1667 above. It defaults to the --with-auto-load-dir setting.
1669 --without-auto-load-safe-path
1670 Set 'set auto-load safe-path' to '/', effectively disabling this
1673 * New remote packets
1675 z0/z1 conditional breakpoints extension
1677 The z0/z1 breakpoint insertion packets have been extended to carry
1678 a list of conditional expressions over to the remote stub depending on the
1679 condition evaluation mode. The use of this extension can be controlled
1680 via the "set remote conditional-breakpoints-packet" command.
1684 Specify the signals which the remote stub may pass to the debugged
1685 program without GDB involvement.
1687 * New command line options
1689 --init-command=FILE, -ix Like --command, -x but execute it
1690 before loading inferior.
1691 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1692 execute it before loading inferior.
1694 *** Changes in GDB 7.4
1696 * GDB now handles ambiguous linespecs more consistently; the existing
1697 FILE:LINE support has been expanded to other types of linespecs. A
1698 breakpoint will now be set on all matching locations in all
1699 inferiors, and locations will be added or removed according to
1702 * GDB now allows you to skip uninteresting functions and files when
1703 stepping with the "skip function" and "skip file" commands.
1705 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1706 and "show remote hardware-watchpoint-length-limit". These allows to
1707 set or show the maximum length limit (in bytes) of a remote
1708 target hardware watchpoint.
1710 This allows e.g. to use "unlimited" hardware watchpoints with the
1711 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1712 watchpoints are slower than real hardware watchpoints but are
1713 significantly faster than gdb software watchpoints.
1717 ** The register_pretty_printer function in module gdb.printing now takes
1718 an optional `replace' argument. If True, the new printer replaces any
1721 ** The "maint set python print-stack on|off" command has been
1722 deprecated and will be deleted in GDB 7.5.
1723 A new command: "set python print-stack none|full|message" has
1724 replaced it. Additionally, the default for "print-stack" is
1725 now "message", which just prints the error message without
1728 ** A prompt substitution hook (prompt_hook) is now available to the
1731 ** A new Python module, gdb.prompt has been added to the GDB Python
1732 modules library. This module provides functionality for
1733 escape sequences in prompts (used by set/show
1734 extended-prompt). These escape sequences are replaced by their
1735 corresponding value.
1737 ** Python commands and convenience-functions located in
1738 'data-directory'/python/gdb/command and
1739 'data-directory'/python/gdb/function are now automatically loaded
1742 ** Blocks now provide four new attributes. global_block and
1743 static_block will return the global and static blocks
1744 respectively. is_static and is_global are boolean attributes
1745 that indicate if the block is one of those two types.
1747 ** Symbols now provide the "type" attribute, the type of the symbol.
1749 ** The "gdb.breakpoint" function has been deprecated in favor of
1752 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1753 of a function. This class is based on the "finish" command
1754 available in the CLI.
1756 ** Type objects for struct and union types now allow access to
1757 the fields using standard Python dictionary (mapping) methods.
1758 For example, "some_type['myfield']" now works, as does
1759 "some_type.items()".
1761 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1764 ** A new function, "deep_items" has been added to the gdb.types
1765 module in the GDB Python modules library. This function returns
1766 an iterator over the fields of a struct or union type. Unlike
1767 the standard Python "iteritems" method, it will recursively traverse
1768 any anonymous fields.
1772 ** "*stopped" events can report several new "reason"s, such as
1775 ** Breakpoint changes are now notified using new async records, like
1776 "=breakpoint-modified".
1778 ** New command -ada-task-info.
1780 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1781 $sdir specifies the default system locations of shared libraries.
1782 $pdir specifies the directory where the libpthread used by the application
1785 GDB no longer looks in $sdir and $pdir after it has searched the directories
1786 mentioned in libthread-db-search-path. If you want to search those
1787 directories, they must be specified in libthread-db-search-path.
1788 The default value of libthread-db-search-path on GNU/Linux and Solaris
1789 systems is now "$sdir:$pdir".
1791 $pdir is not supported by gdbserver, it is currently ignored.
1792 $sdir is supported by gdbserver.
1794 * New configure option --with-iconv-bin.
1795 When using the internationalization support like the one in the GNU C
1796 library, GDB will invoke the "iconv" program to get a list of supported
1797 character sets. If this program lives in a non-standard location, one can
1798 use this option to specify where to find it.
1800 * When natively debugging programs on PowerPC BookE processors running
1801 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1802 watchpoints, which specify a mask in addition to an address to watch.
1803 The mask specifies that some bits of an address (the bits which are
1804 reset in the mask) should be ignored when matching the address accessed
1805 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1806 section in the user manual for more details.
1808 * The new option --once causes GDBserver to stop listening for connections once
1809 the first connection is made. The listening port used by GDBserver will
1810 become available after that.
1812 * New commands "info macros" and "alias" have been added.
1814 * New function parameters suffix @entry specifies value of function parameter
1815 at the time the function got called. Entry values are available only since
1821 "!" is now an alias of the "shell" command.
1822 Note that no space is needed between "!" and SHELL COMMAND.
1826 watch EXPRESSION mask MASK_VALUE
1827 The watch command now supports the mask argument which allows creation
1828 of masked watchpoints, if the current architecture supports this feature.
1830 info auto-load-scripts [REGEXP]
1831 This command was formerly named "maintenance print section-scripts".
1832 It is now generally useful and is no longer a maintenance-only command.
1834 info macro [-all] [--] MACRO
1835 The info macro command has new options `-all' and `--'. The first for
1836 printing all definitions of a macro. The second for explicitly specifying
1837 the end of arguments and the beginning of the macro name in case the macro
1838 name starts with a hyphen.
1840 collect[/s] EXPRESSIONS
1841 The tracepoint collect command now takes an optional modifier "/s"
1842 that directs it to dereference pointer-to-character types and
1843 collect the bytes of memory up to a zero byte. The behavior is
1844 similar to what you see when you use the regular print command on a
1845 string. An optional integer following the "/s" sets a bound on the
1846 number of bytes that will be collected.
1849 The trace start command now interprets any supplied arguments as a
1850 note to be recorded with the trace run, with an effect similar to
1851 setting the variable trace-notes.
1854 The trace stop command now interprets any arguments as a note to be
1855 mentioned along with the tstatus report that the trace was stopped
1856 with a command. The effect is similar to setting the variable
1859 * Tracepoints can now be enabled and disabled at any time after a trace
1860 experiment has been started using the standard "enable" and "disable"
1861 commands. It is now possible to start a trace experiment with no enabled
1862 tracepoints; GDB will display a warning, but will allow the experiment to
1863 begin, assuming that tracepoints will be enabled as needed while the trace
1866 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1867 locations with 4-byte instructions, when they were previously
1868 limited to locations with instructions of 5 bytes or longer.
1872 set debug dwarf2-read
1873 show debug dwarf2-read
1874 Turns on or off display of debugging messages related to reading
1875 DWARF debug info. The default is off.
1877 set debug symtab-create
1878 show debug symtab-create
1879 Turns on or off display of debugging messages related to symbol table
1880 creation. The default is off.
1883 show extended-prompt
1884 Set the GDB prompt, and allow escape sequences to be inserted to
1885 display miscellaneous information (see 'help set extended-prompt'
1886 for the list of sequences). This prompt (and any information
1887 accessed through the escape sequences) is updated every time the
1888 prompt is displayed.
1890 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1891 show print entry-values
1892 Set printing of frame argument values at function entry. In some cases
1893 GDB can determine the value of function argument which was passed by the
1894 function caller, even if the value was modified inside the called function.
1896 set debug entry-values
1897 show debug entry-values
1898 Control display of debugging info for determining frame argument values at
1899 function entry and virtual tail call frames.
1901 set basenames-may-differ
1902 show basenames-may-differ
1903 Set whether a source file may have multiple base names.
1904 (A "base name" is the name of a file with the directory part removed.
1905 Example: The base name of "/home/user/hello.c" is "hello.c".)
1906 If set, GDB will canonicalize file names (e.g., expand symlinks)
1907 before comparing them. Canonicalization is an expensive operation,
1908 but it allows the same file be known by more than one base name.
1909 If not set (the default), all source files are assumed to have just
1910 one base name, and gdb will do file name comparisons more efficiently.
1916 Set a user name and notes for the current and any future trace runs.
1917 This is useful for long-running and/or disconnected traces, to
1918 inform others (or yourself) as to who is running the trace, supply
1919 contact information, or otherwise explain what is going on.
1921 set trace-stop-notes
1922 show trace-stop-notes
1923 Set a note attached to the trace run, that is displayed when the
1924 trace has been stopped by a tstop command. This is useful for
1925 instance as an explanation, if you are stopping a trace run that was
1926 started by someone else.
1928 * New remote packets
1932 Dynamically enable a tracepoint in a started trace experiment.
1936 Dynamically disable a tracepoint in a started trace experiment.
1940 Set the user and notes of the trace run.
1944 Query the current status of a tracepoint.
1948 Query the minimum length of instruction at which a fast tracepoint may
1951 * Dcache size (number of lines) and line-size are now runtime-configurable
1952 via "set dcache line" and "set dcache line-size" commands.
1956 Texas Instruments TMS320C6x tic6x-*-*
1960 Renesas RL78 rl78-*-elf
1962 *** Changes in GDB 7.3.1
1964 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1966 *** Changes in GDB 7.3
1968 * GDB has a new command: "thread find [REGEXP]".
1969 It finds the thread id whose name, target id, or thread extra info
1970 matches the given regular expression.
1972 * The "catch syscall" command now works on mips*-linux* targets.
1974 * The -data-disassemble MI command now supports modes 2 and 3 for
1975 dumping the instruction opcodes.
1977 * New command line options
1979 -data-directory DIR Specify DIR as the "data-directory".
1980 This is mostly for testing purposes.
1982 * The "maint set python auto-load on|off" command has been renamed to
1983 "set auto-load-scripts on|off".
1985 * GDB has a new command: "set directories".
1986 It is like the "dir" command except that it replaces the
1987 source path list instead of augmenting it.
1989 * GDB now understands thread names.
1991 On GNU/Linux, "info threads" will display the thread name as set by
1992 prctl or pthread_setname_np.
1994 There is also a new command, "thread name", which can be used to
1995 assign a name internally for GDB to display.
1998 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1999 has been integrated into GDB.
2003 ** The function gdb.Write now accepts an optional keyword 'stream'.
2004 This keyword, when provided, will direct the output to either
2005 stdout, stderr, or GDB's logging output.
2007 ** Parameters can now be be sub-classed in Python, and in particular
2008 you may implement the get_set_doc and get_show_doc functions.
2009 This improves how Parameter set/show documentation is processed
2010 and allows for more dynamic content.
2012 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2013 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2014 have an is_valid method.
2016 ** Breakpoints can now be sub-classed in Python, and in particular
2017 you may implement a 'stop' function that is executed each time
2018 the inferior reaches that breakpoint.
2020 ** New function gdb.lookup_global_symbol looks up a global symbol.
2022 ** GDB values in Python are now callable if the value represents a
2023 function. For example, if 'some_value' represents a function that
2024 takes two integer parameters and returns a value, you can call
2025 that function like so:
2027 result = some_value (10,20)
2029 ** Module gdb.types has been added.
2030 It contains a collection of utilities for working with gdb.Types objects:
2031 get_basic_type, has_field, make_enum_dict.
2033 ** Module gdb.printing has been added.
2034 It contains utilities for writing and registering pretty-printers.
2035 New classes: PrettyPrinter, SubPrettyPrinter,
2036 RegexpCollectionPrettyPrinter.
2037 New function: register_pretty_printer.
2039 ** New commands "info pretty-printers", "enable pretty-printer" and
2040 "disable pretty-printer" have been added.
2042 ** gdb.parameter("directories") is now available.
2044 ** New function gdb.newest_frame returns the newest frame in the
2047 ** The gdb.InferiorThread class has a new "name" attribute. This
2048 holds the thread's name.
2050 ** Python Support for Inferior events.
2051 Python scripts can add observers to be notified of events
2052 occurring in the process being debugged.
2053 The following events are currently supported:
2054 - gdb.events.cont Continue event.
2055 - gdb.events.exited Inferior exited event.
2056 - gdb.events.stop Signal received, and Breakpoint hit events.
2060 ** GDB now puts template parameters in scope when debugging in an
2061 instantiation. For example, if you have:
2063 template<int X> int func (void) { return X; }
2065 then if you step into func<5>, "print X" will show "5". This
2066 feature requires proper debuginfo support from the compiler; it
2067 was added to GCC 4.5.
2069 ** The motion commands "next", "finish", "until", and "advance" now
2070 work better when exceptions are thrown. In particular, GDB will
2071 no longer lose control of the inferior; instead, the GDB will
2072 stop the inferior at the point at which the exception is caught.
2073 This functionality requires a change in the exception handling
2074 code that was introduced in GCC 4.5.
2076 * GDB now follows GCC's rules on accessing volatile objects when
2077 reading or writing target state during expression evaluation.
2078 One notable difference to prior behavior is that "print x = 0"
2079 no longer generates a read of x; the value of the assignment is
2080 now always taken directly from the value being assigned.
2082 * GDB now has some support for using labels in the program's source in
2083 linespecs. For instance, you can use "advance label" to continue
2084 execution to a label.
2086 * GDB now has support for reading and writing a new .gdb_index
2087 section. This section holds a fast index of DWARF debugging
2088 information and can be used to greatly speed up GDB startup and
2089 operation. See the documentation for `save gdb-index' for details.
2091 * The "watch" command now accepts an optional "-location" argument.
2092 When used, this causes GDB to watch the memory referred to by the
2093 expression. Such a watchpoint is never deleted due to it going out
2096 * GDB now supports thread debugging of core dumps on GNU/Linux.
2098 GDB now activates thread debugging using the libthread_db library
2099 when debugging GNU/Linux core dumps, similarly to when debugging
2100 live processes. As a result, when debugging a core dump file, GDB
2101 is now able to display pthread_t ids of threads. For example, "info
2102 threads" shows the same output as when debugging the process when it
2103 was live. In earlier releases, you'd see something like this:
2106 * 1 LWP 6780 main () at main.c:10
2108 While now you see this:
2111 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2113 It is also now possible to inspect TLS variables when debugging core
2116 When debugging a core dump generated on a machine other than the one
2117 used to run GDB, you may need to point GDB at the correct
2118 libthread_db library with the "set libthread-db-search-path"
2119 command. See the user manual for more details on this command.
2121 * When natively debugging programs on PowerPC BookE processors running
2122 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2123 which stop execution of the inferior whenever it executes an instruction
2124 at any address within the specified range. See the "PowerPC Embedded"
2125 section in the user manual for more details.
2127 * New features in the GDB remote stub, GDBserver
2129 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2130 and i686 LynxOS (version 5.x).
2132 ** GDBserver is now supported on Blackfin Linux.
2134 * New native configurations
2136 ia64 HP-UX ia64-*-hpux*
2140 Analog Devices, Inc. Blackfin Processor bfin-*
2142 * Ada task switching is now supported on sparc-elf targets when
2143 debugging a program using the Ravenscar Profile. For more information,
2144 see the "Tasking Support when using the Ravenscar Profile" section
2145 in the GDB user manual.
2147 * Guile support was removed.
2149 * New features in the GNU simulator
2151 ** The --map-info flag lists all known core mappings.
2153 ** CFI flashes may be simulated via the "cfi" device.
2155 *** Changes in GDB 7.2
2157 * Shared library support for remote targets by default
2159 When GDB is configured for a generic, non-OS specific target, like
2160 for example, --target=arm-eabi or one of the many *-*-elf targets,
2161 GDB now queries remote stubs for loaded shared libraries using the
2162 `qXfer:libraries:read' packet. Previously, shared library support
2163 was always disabled for such configurations.
2167 ** Argument Dependent Lookup (ADL)
2169 In C++ ADL lookup directs function search to the namespaces of its
2170 arguments even if the namespace has not been imported.
2180 Here the compiler will search for `foo' in the namespace of 'b'
2181 and find A::foo. GDB now supports this. This construct is commonly
2182 used in the Standard Template Library for operators.
2184 ** Improved User Defined Operator Support
2186 In addition to member operators, GDB now supports lookup of operators
2187 defined in a namespace and imported with a `using' directive, operators
2188 defined in the global scope, operators imported implicitly from an
2189 anonymous namespace, and the ADL operators mentioned in the previous
2191 GDB now also supports proper overload resolution for all the previously
2192 mentioned flavors of operators.
2194 ** static const class members
2196 Printing of static const class members that are initialized in the
2197 class definition has been fixed.
2199 * Windows Thread Information Block access.
2201 On Windows targets, GDB now supports displaying the Windows Thread
2202 Information Block (TIB) structure. This structure is visible either
2203 by using the new command `info w32 thread-information-block' or, by
2204 dereferencing the new convenience variable named `$_tlb', a
2205 thread-specific pointer to the TIB. This feature is also supported
2206 when remote debugging using GDBserver.
2208 * Static tracepoints
2210 Static tracepoints are calls in the user program into a tracing
2211 library. One such library is a port of the LTTng kernel tracer to
2212 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2213 When debugging with GDBserver, GDB now supports combining the GDB
2214 tracepoint machinery with such libraries. For example: the user can
2215 use GDB to probe a static tracepoint marker (a call from the user
2216 program into the tracing library) with the new "strace" command (see
2217 "New commands" below). This creates a "static tracepoint" in the
2218 breakpoint list, that can be manipulated with the same feature set
2219 as fast and regular tracepoints. E.g., collect registers, local and
2220 global variables, collect trace state variables, and define
2221 tracepoint conditions. In addition, the user can collect extra
2222 static tracepoint marker specific data, by collecting the new
2223 $_sdata internal variable. When analyzing the trace buffer, you can
2224 inspect $_sdata like any other variable available to GDB. For more
2225 information, see the "Tracepoints" chapter in GDB user manual. New
2226 remote packets have been defined to support static tracepoints, see
2227 the "New remote packets" section below.
2229 * Better reconstruction of tracepoints after disconnected tracing
2231 GDB will attempt to download the original source form of tracepoint
2232 definitions when starting a trace run, and then will upload these
2233 upon reconnection to the target, resulting in a more accurate
2234 reconstruction of the tracepoints that are in use on the target.
2238 You can now exercise direct control over the ways that GDB can
2239 affect your program. For instance, you can disallow the setting of
2240 breakpoints, so that the program can run continuously (assuming
2241 non-stop mode). In addition, the "observer" variable is available
2242 to switch all of the different controls; in observer mode, GDB
2243 cannot affect the target's behavior at all, which is useful for
2244 tasks like diagnosing live systems in the field.
2246 * The new convenience variable $_thread holds the number of the
2249 * New remote packets
2253 Return the address of the Windows Thread Information Block of a given thread.
2257 In response to several of the tracepoint packets, the target may now
2258 also respond with a number of intermediate `qRelocInsn' request
2259 packets before the final result packet, to have GDB handle
2260 relocating an instruction to execute at a different address. This
2261 is particularly useful for stubs that support fast tracepoints. GDB
2262 reports support for this feature in the qSupported packet.
2266 List static tracepoint markers in the target program.
2270 List static tracepoint markers at a given address in the target
2273 qXfer:statictrace:read
2275 Read the static trace data collected (by a `collect $_sdata'
2276 tracepoint action). The remote stub reports support for this packet
2277 to gdb's qSupported query.
2281 Send the current settings of GDB's permission flags.
2285 Send part of the source (textual) form of a tracepoint definition,
2286 which includes location, conditional, and action list.
2288 * The source command now accepts a -s option to force searching for the
2289 script in the source search path even if the script name specifies
2292 * New features in the GDB remote stub, GDBserver
2294 - GDBserver now support tracepoints (including fast tracepoints, and
2295 static tracepoints). The feature is currently supported by the
2296 i386-linux and amd64-linux builds. See the "Tracepoints support
2297 in gdbserver" section in the manual for more information.
2299 GDBserver JIT compiles the tracepoint's conditional agent
2300 expression bytecode into native code whenever possible for low
2301 overhead dynamic tracepoints conditionals. For such tracepoints,
2302 an expression that examines program state is evaluated when the
2303 tracepoint is reached, in order to determine whether to capture
2304 trace data. If the condition is simple and false, processing the
2305 tracepoint finishes very quickly and no data is gathered.
2307 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2308 for static tracepoints support.
2310 - GDBserver now supports x86_64 Windows 64-bit debugging.
2312 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2313 it understands register description.
2315 * The --batch flag now disables pagination and queries.
2317 * X86 general purpose registers
2319 GDB now supports reading/writing byte, word and double-word x86
2320 general purpose registers directly. This means you can use, say,
2321 $ah or $ax to refer, respectively, to the byte register AH and
2322 16-bit word register AX that are actually portions of the 32-bit
2323 register EAX or 64-bit register RAX.
2325 * The `commands' command now accepts a range of breakpoints to modify.
2326 A plain `commands' following a command that creates multiple
2327 breakpoints affects all the breakpoints set by that command. This
2328 applies to breakpoints set by `rbreak', and also applies when a
2329 single `break' command creates multiple breakpoints (e.g.,
2330 breakpoints on overloaded c++ functions).
2332 * The `rbreak' command now accepts a filename specification as part of
2333 its argument, limiting the functions selected by the regex to those
2334 in the specified file.
2336 * Support for remote debugging Windows and SymbianOS shared libraries
2337 from Unix hosts has been improved. Non Windows GDB builds now can
2338 understand target reported file names that follow MS-DOS based file
2339 system semantics, such as file names that include drive letters and
2340 use the backslash character as directory separator. This makes it
2341 possible to transparently use the "set sysroot" and "set
2342 solib-search-path" on Unix hosts to point as host copies of the
2343 target's shared libraries. See the new command "set
2344 target-file-system-kind" described below, and the "Commands to
2345 specify files" section in the user manual for more information.
2349 eval template, expressions...
2350 Convert the values of one or more expressions under the control
2351 of the string template to a command line, and call it.
2353 set target-file-system-kind unix|dos-based|auto
2354 show target-file-system-kind
2355 Set or show the assumed file system kind for target reported file
2358 save breakpoints <filename>
2359 Save all current breakpoint definitions to a file suitable for use
2360 in a later debugging session. To read the saved breakpoint
2361 definitions, use the `source' command.
2363 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2366 info static-tracepoint-markers
2367 Display information about static tracepoint markers in the target.
2369 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2370 Define a static tracepoint by probing a marker at the given
2371 function, line, address, or marker ID.
2375 Enable and disable observer mode.
2377 set may-write-registers on|off
2378 set may-write-memory on|off
2379 set may-insert-breakpoints on|off
2380 set may-insert-tracepoints on|off
2381 set may-insert-fast-tracepoints on|off
2382 set may-interrupt on|off
2383 Set individual permissions for GDB effects on the target. Note that
2384 some of these settings can have undesirable or surprising
2385 consequences, particularly when changed in the middle of a session.
2386 For instance, disabling the writing of memory can prevent
2387 breakpoints from being inserted, cause single-stepping to fail, or
2388 even crash your program, if you disable after breakpoints have been
2389 inserted. However, GDB should not crash.
2391 set record memory-query on|off
2392 show record memory-query
2393 Control whether to stop the inferior if memory changes caused
2394 by an instruction cannot be recorded.
2399 The disassemble command now supports "start,+length" form of two arguments.
2403 ** GDB now provides a new directory location, called the python directory,
2404 where Python scripts written for GDB can be installed. The location
2405 of that directory is <data-directory>/python, where <data-directory>
2406 is the GDB data directory. For more details, see section `Scripting
2407 GDB using Python' in the manual.
2409 ** The GDB Python API now has access to breakpoints, symbols, symbol
2410 tables, program spaces, inferiors, threads and frame's code blocks.
2411 Additionally, GDB Parameters can now be created from the API, and
2412 manipulated via set/show in the CLI.
2414 ** New functions gdb.target_charset, gdb.target_wide_charset,
2415 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2417 ** New exception gdb.GdbError.
2419 ** Pretty-printers are now also looked up in the current program space.
2421 ** Pretty-printers can now be individually enabled and disabled.
2423 ** GDB now looks for names of Python scripts to auto-load in a
2424 special section named `.debug_gdb_scripts', in addition to looking
2425 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2427 * Tracepoint actions were unified with breakpoint commands. In particular,
2428 there are no longer differences in "info break" output for breakpoints and
2429 tracepoints and the "commands" command can be used for both tracepoints and
2430 regular breakpoints.
2434 ARM Symbian arm*-*-symbianelf*
2436 * D language support.
2437 GDB now supports debugging programs written in the D programming
2440 * GDB now supports the extended ptrace interface for PowerPC which is
2441 available since Linux kernel version 2.6.34. This automatically enables
2442 any hardware breakpoints and additional hardware watchpoints available in
2443 the processor. The old ptrace interface exposes just one hardware
2444 watchpoint and no hardware breakpoints.
2446 * GDB is now able to use the Data Value Compare (DVC) register available on
2447 embedded PowerPC processors to implement in hardware simple watchpoint
2448 conditions of the form:
2450 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2452 This works in native GDB running on Linux kernels with the extended ptrace
2453 interface mentioned above.
2455 *** Changes in GDB 7.1
2459 ** Namespace Support
2461 GDB now supports importing of namespaces in C++. This enables the
2462 user to inspect variables from imported namespaces. Support for
2463 namepace aliasing has also been added. So, if a namespace is
2464 aliased in the current scope (e.g. namepace C=A; ) the user can
2465 print variables using the alias (e.g. (gdb) print C::x).
2469 All known bugs relating to the printing of virtual base class were
2470 fixed. It is now possible to call overloaded static methods using a
2475 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2476 and reinterpret_cast<> are now handled by the C++ expression parser.
2480 Xilinx MicroBlaze microblaze-*-*
2485 Xilinx MicroBlaze microblaze
2488 * Multi-program debugging.
2490 GDB now has support for multi-program (a.k.a. multi-executable or
2491 multi-exec) debugging. This allows for debugging multiple inferiors
2492 simultaneously each running a different program under the same GDB
2493 session. See "Debugging Multiple Inferiors and Programs" in the
2494 manual for more information. This implied some user visible changes
2495 in the multi-inferior support. For example, "info inferiors" now
2496 lists inferiors that are not running yet or that have exited
2497 already. See also "New commands" and "New options" below.
2499 * New tracing features
2501 GDB's tracepoint facility now includes several new features:
2503 ** Trace state variables
2505 GDB tracepoints now include support for trace state variables, which
2506 are variables managed by the target agent during a tracing
2507 experiment. They are useful for tracepoints that trigger each
2508 other, so for instance one tracepoint can count hits in a variable,
2509 and then a second tracepoint has a condition that is true when the
2510 count reaches a particular value. Trace state variables share the
2511 $-syntax of GDB convenience variables, and can appear in both
2512 tracepoint actions and condition expressions. Use the "tvariable"
2513 command to create, and "info tvariables" to view; see "Trace State
2514 Variables" in the manual for more detail.
2518 GDB now includes an option for defining fast tracepoints, which
2519 targets may implement more efficiently, such as by installing a jump
2520 into the target agent rather than a trap instruction. The resulting
2521 speedup can be by two orders of magnitude or more, although the
2522 tradeoff is that some program locations on some target architectures
2523 might not allow fast tracepoint installation, for instance if the
2524 instruction to be replaced is shorter than the jump. To request a
2525 fast tracepoint, use the "ftrace" command, with syntax identical to
2526 the regular trace command.
2528 ** Disconnected tracing
2530 It is now possible to detach GDB from the target while it is running
2531 a trace experiment, then reconnect later to see how the experiment
2532 is going. In addition, a new variable disconnected-tracing lets you
2533 tell the target agent whether to continue running a trace if the
2534 connection is lost unexpectedly.
2538 GDB now has the ability to save the trace buffer into a file, and
2539 then use that file as a target, similarly to you can do with
2540 corefiles. You can select trace frames, print data that was
2541 collected in them, and use tstatus to display the state of the
2542 tracing run at the moment that it was saved. To create a trace
2543 file, use "tsave <filename>", and to use it, do "target tfile
2546 ** Circular trace buffer
2548 You can ask the target agent to handle the trace buffer as a
2549 circular buffer, discarding the oldest trace frames to make room for
2550 newer ones, by setting circular-trace-buffer to on. This feature may
2551 not be available for all target agents.
2556 The disassemble command, when invoked with two arguments, now requires
2557 the arguments to be comma-separated.
2560 The info variables command now displays variable definitions. Files
2561 which only declare a variable are not shown.
2564 The source command is now capable of sourcing Python scripts.
2565 This feature is dependent on the debugger being build with Python
2568 Related to this enhancement is also the introduction of a new command
2569 "set script-extension" (see below).
2571 * New commands (for set/show, see "New options" below)
2573 record save [<FILENAME>]
2574 Save a file (in core file format) containing the process record
2575 execution log for replay debugging at a later time.
2577 record restore <FILENAME>
2578 Restore the process record execution log that was saved at an
2579 earlier time, for replay debugging.
2581 add-inferior [-copies <N>] [-exec <FILENAME>]
2584 clone-inferior [-copies <N>] [ID]
2585 Make a new inferior ready to execute the same program another
2586 inferior has loaded.
2591 maint info program-spaces
2592 List the program spaces loaded into GDB.
2594 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2595 show remote interrupt-sequence
2596 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2597 as the sequence to the remote target in order to interrupt the execution.
2598 Ctrl-C is a default. Some system prefers BREAK which is high level of
2599 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2600 Magic SysRq g. It is BREAK signal and character 'g'.
2602 set remote interrupt-on-connect [on | off]
2603 show remote interrupt-on-connect
2604 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2605 remote target when gdb connects to it. This is needed when you debug
2608 set remotebreak [on | off]
2610 Deprecated. Use "set/show remote interrupt-sequence" instead.
2612 tvariable $NAME [ = EXP ]
2613 Create or modify a trace state variable.
2616 List trace state variables and their values.
2618 delete tvariable $NAME ...
2619 Delete one or more trace state variables.
2622 Evaluate the given expressions without collecting anything into the
2623 trace buffer. (Valid in tracepoint actions only.)
2625 ftrace FN / FILE:LINE / *ADDR
2626 Define a fast tracepoint at the given function, line, or address.
2628 * New expression syntax
2630 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2631 GDB now parses 0b101010 identically with 42.
2635 set follow-exec-mode new|same
2636 show follow-exec-mode
2637 Control whether GDB reuses the same inferior across an exec call or
2638 creates a new one. This is useful to be able to restart the old
2639 executable after the inferior having done an exec call.
2641 set default-collect EXPR, ...
2642 show default-collect
2643 Define a list of expressions to be collected at each tracepoint.
2644 This is a useful way to ensure essential items are not overlooked,
2645 such as registers or a critical global variable.
2647 set disconnected-tracing
2648 show disconnected-tracing
2649 If set to 1, the target is instructed to continue tracing if it
2650 loses its connection to GDB. If 0, the target is to stop tracing
2653 set circular-trace-buffer
2654 show circular-trace-buffer
2655 If set to on, the target is instructed to use a circular trace buffer
2656 and discard the oldest trace frames instead of stopping the trace due
2657 to a full trace buffer. If set to off, the trace stops when the buffer
2658 fills up. Some targets may not support this.
2660 set script-extension off|soft|strict
2661 show script-extension
2662 If set to "off", the debugger does not perform any script language
2663 recognition, and all sourced files are assumed to be GDB scripts.
2664 If set to "soft" (the default), files are sourced according to
2665 filename extension, falling back to GDB scripts if the first
2667 If set to "strict", files are sourced according to filename extension.
2669 set ada trust-PAD-over-XVS on|off
2670 show ada trust-PAD-over-XVS
2671 If off, activate a workaround against a bug in the debugging information
2672 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2673 the GCC sources for more information about the GNAT encoding and
2674 PAD types in particular). It is always safe to set this option to
2675 off, but this introduces a slight performance penalty. The default
2678 * Python API Improvements
2680 ** GDB provides the new class gdb.LazyString. This is useful in
2681 some pretty-printing cases. The new method gdb.Value.lazy_string
2682 provides a simple way to create objects of this type.
2684 ** The fields returned by gdb.Type.fields now have an
2685 `is_base_class' attribute.
2687 ** The new method gdb.Type.range returns the range of an array type.
2689 ** The new method gdb.parse_and_eval can be used to parse and
2690 evaluate an expression.
2692 * New remote packets
2695 Define a trace state variable.
2698 Get the current value of a trace state variable.
2701 Set desired tracing behavior upon disconnection.
2704 Set the trace buffer to be linear or circular.
2707 Get data about the tracepoints currently in use.
2711 Process record now works correctly with hardware watchpoints.
2713 Multiple bug fixes have been made to the mips-irix port, making it
2714 much more reliable. In particular:
2715 - Debugging threaded applications is now possible again. Previously,
2716 GDB would hang while starting the program, or while waiting for
2717 the program to stop at a breakpoint.
2718 - Attaching to a running process no longer hangs.
2719 - An error occurring while loading a core file has been fixed.
2720 - Changing the value of the PC register now works again. This fixes
2721 problems observed when using the "jump" command, or when calling
2722 a function from GDB, or even when assigning a new value to $pc.
2723 - With the "finish" and "return" commands, the return value for functions
2724 returning a small array is now correctly printed.
2725 - It is now possible to break on shared library code which gets executed
2726 during a shared library init phase (code executed while executing
2727 their .init section). Previously, the breakpoint would have no effect.
2728 - GDB is now able to backtrace through the signal handler for
2729 non-threaded programs.
2731 PIE (Position Independent Executable) programs debugging is now supported.
2732 This includes debugging execution of PIC (Position Independent Code) shared
2733 libraries although for that, it should be possible to run such libraries as an
2736 *** Changes in GDB 7.0
2738 * GDB now has an interface for JIT compilation. Applications that
2739 dynamically generate code can create symbol files in memory and register
2740 them with GDB. For users, the feature should work transparently, and
2741 for JIT developers, the interface is documented in the GDB manual in the
2742 "JIT Compilation Interface" chapter.
2744 * Tracepoints may now be conditional. The syntax is as for
2745 breakpoints; either an "if" clause appended to the "trace" command,
2746 or the "condition" command is available. GDB sends the condition to
2747 the target for evaluation using the same bytecode format as is used
2748 for tracepoint actions.
2750 * The disassemble command now supports: an optional /r modifier, print the
2751 raw instructions in hex as well as in symbolic form, and an optional /m
2752 modifier to print mixed source+assembly.
2754 * Process record and replay
2756 In a architecture environment that supports ``process record and
2757 replay'', ``process record and replay'' target can record a log of
2758 the process execution, and replay it with both forward and reverse
2761 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2762 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2763 set execution-direction {forward|reverse}, for targets that support
2766 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2767 feature is available with a native GDB running on kernel version
2770 * GDB now has support for multi-byte and wide character sets on the
2771 target. Strings whose character type is wchar_t, char16_t, or
2772 char32_t are now correctly printed. GDB supports wide- and unicode-
2773 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2774 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2775 `printf'. This feature requires iconv to work properly; if your
2776 system does not have a working iconv, GDB can use GNU libiconv. See
2777 the installation instructions for more information.
2779 * GDB now supports automatic retrieval of shared library files from
2780 remote targets. To use this feature, specify a system root that begins
2781 with the `remote:' prefix, either via the `set sysroot' command or via
2782 the `--with-sysroot' configure-time option.
2784 * "info sharedlibrary" now takes an optional regex of libraries to show,
2785 and it now reports if a shared library has no debugging information.
2787 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2788 now complete on file names.
2790 * When completing in expressions, gdb will attempt to limit
2791 completions to allowable structure or union fields, where appropriate.
2792 For instance, consider:
2794 # struct example { int f1; double f2; };
2795 # struct example variable;
2798 If the user types TAB at the end of this command line, the available
2799 completions will be "f1" and "f2".
2801 * Inlined functions are now supported. They show up in backtraces, and
2802 the "step", "next", and "finish" commands handle them automatically.
2804 * GDB now supports the token-splicing (##) and stringification (#)
2805 operators when expanding macros. It also supports variable-arity
2808 * GDB now supports inspecting extra signal information, exported by
2809 the new $_siginfo convenience variable. The feature is currently
2810 implemented on linux ARM, i386 and amd64.
2812 * GDB can now display the VFP floating point registers and NEON vector
2813 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2814 can provide these registers (requires Linux 2.6.30 or later). Remote
2815 and simulator targets may also provide them.
2817 * New remote packets
2820 Search memory for a sequence of bytes.
2823 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2824 operation over reliable transport links. Use of this packet is
2825 controlled by the `set remote noack-packet' command.
2828 Kill the process with the specified process ID. Use this in preference
2829 to `k' when multiprocess protocol extensions are supported.
2832 Obtains additional operating system information
2836 Read or write additional signal information.
2838 * Removed remote protocol undocumented extension
2840 An undocumented extension to the remote protocol's `S' stop reply
2841 packet that permited the stub to pass a process id was removed.
2842 Remote servers should use the `T' stop reply packet instead.
2844 * GDB now supports multiple function calling conventions according to the
2845 DWARF-2 DW_AT_calling_convention function attribute.
2847 * The SH target utilizes the aforementioned change to distinguish between gcc
2848 and Renesas calling convention. It also adds the new CLI commands
2849 `set/show sh calling-convention'.
2851 * GDB can now read compressed debug sections, as produced by GNU gold
2852 with the --compress-debug-sections=zlib flag.
2854 * 64-bit core files are now supported on AIX.
2856 * Thread switching is now supported on Tru64.
2858 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2859 which will be allocated using malloc later in program execution.
2861 * The qXfer:libraries:read remote procotol packet now allows passing a
2862 list of section offsets.
2864 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2865 conditions handling signals delivered during attach or thread creation
2866 have also been fixed.
2868 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2869 From the user's standpoint, all unqualified instances of True and False
2870 are treated as the standard definitions, regardless of context.
2872 * GDB now parses C++ symbol and type names more flexibly. For
2875 template<typename T> class C { };
2878 GDB will now correctly handle all of:
2880 ptype C<char const *>
2881 ptype C<char const*>
2882 ptype C<const char *>
2883 ptype C<const char*>
2885 * New features in the GDB remote stub, gdbserver
2887 - The "--wrapper" command-line argument tells gdbserver to use a
2888 wrapper program to launch programs for debugging.
2890 - On PowerPC and S/390 targets, it is now possible to use a single
2891 gdbserver executable to debug both 32-bit and 64-bit programs.
2892 (This requires gdbserver itself to be built as a 64-bit executable.)
2894 - gdbserver uses the new noack protocol mode for TCP connections to
2895 reduce communications latency, if also supported and enabled in GDB.
2897 - Support for the sparc64-linux-gnu target is now included in
2900 - The amd64-linux build of gdbserver now supports debugging both
2901 32-bit and 64-bit programs.
2903 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2904 now support hardware watchpoints, and will use them automatically
2909 GDB now has support for scripting using Python. Whether this is
2910 available is determined at configure time.
2912 New GDB commands can now be written in Python.
2914 * Ada tasking support
2916 Ada tasks can now be inspected in GDB. The following commands have
2920 Print the list of Ada tasks.
2922 Print detailed information about task number N.
2924 Print the task number of the current task.
2926 Switch the context of debugging to task number N.
2928 * Support for user-defined prefixed commands. The "define" command can
2929 add new commands to existing prefixes, e.g. "target".
2931 * Multi-inferior, multi-process debugging.
2933 GDB now has generalized support for multi-inferior debugging. See
2934 "Debugging Multiple Inferiors" in the manual for more information.
2935 Although availability still depends on target support, the command
2936 set is more uniform now. The GNU/Linux specific multi-forks support
2937 has been migrated to this new framework. This implied some user
2938 visible changes; see "New commands" and also "Removed commands"
2941 * Target descriptions can now describe the target OS ABI. See the
2942 "Target Description Format" section in the user manual for more
2945 * Target descriptions can now describe "compatible" architectures
2946 to indicate that the target can execute applications for a different
2947 architecture in addition to those for the main target architecture.
2948 See the "Target Description Format" section in the user manual for
2951 * Multi-architecture debugging.
2953 GDB now includes general supports for debugging applications on
2954 hybrid systems that use more than one single processor architecture
2955 at the same time. Each such hybrid architecture still requires
2956 specific support to be added. The only hybrid architecture supported
2957 in this version of GDB is the Cell Broadband Engine.
2959 * GDB now supports integrated debugging of Cell/B.E. applications that
2960 use both the PPU and SPU architectures. To enable support for hybrid
2961 Cell/B.E. debugging, you need to configure GDB to support both the
2962 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2963 --enable-targets configure option.
2965 * Non-stop mode debugging.
2967 For some targets, GDB now supports an optional mode of operation in
2968 which you can examine stopped threads while other threads continue
2969 to execute freely. This is referred to as non-stop mode, with the
2970 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2971 section in the user manual for more information.
2973 To be able to support remote non-stop debugging, a remote stub needs
2974 to implement the non-stop mode remote protocol extensions, as
2975 described in the "Remote Non-Stop" section of the user manual. The
2976 GDB remote stub, gdbserver, has been adjusted to support these
2977 extensions on linux targets.
2979 * New commands (for set/show, see "New options" below)
2981 catch syscall [NAME(S) | NUMBER(S)]
2982 Catch system calls. Arguments, which should be names of system
2983 calls or their numbers, mean catch only those syscalls. Without
2984 arguments, every syscall will be caught. When the inferior issues
2985 any of the specified syscalls, GDB will stop and announce the system
2986 call, both when it is called and when its call returns. This
2987 feature is currently available with a native GDB running on the
2988 Linux Kernel, under the following architectures: x86, x86_64,
2989 PowerPC and PowerPC64.
2991 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2993 Search memory for a sequence of bytes.
2995 maint set python print-stack
2996 maint show python print-stack
2997 Show a stack trace when an error is encountered in a Python script.
3000 Invoke CODE by passing it to the Python interpreter.
3005 These allow macros to be defined, undefined, and listed
3009 Show operating system information about processes.
3012 List the inferiors currently under GDB's control.
3015 Switch focus to inferior number NUM.
3018 Detach from inferior number NUM.
3021 Kill inferior number NUM.
3025 set spu stop-on-load
3026 show spu stop-on-load
3027 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3029 set spu auto-flush-cache
3030 show spu auto-flush-cache
3031 Control whether to automatically flush the software-managed cache
3032 during Cell/B.E. debugging.
3034 set sh calling-convention
3035 show sh calling-convention
3036 Control the calling convention used when calling SH target functions.
3039 show debug timestamp
3040 Control display of timestamps with GDB debugging output.
3042 set disassemble-next-line
3043 show disassemble-next-line
3044 Control display of disassembled source lines or instructions when
3047 set remote noack-packet
3048 show remote noack-packet
3049 Set/show the use of remote protocol QStartNoAckMode packet. See above
3050 under "New remote packets."
3052 set remote query-attached-packet
3053 show remote query-attached-packet
3054 Control use of remote protocol `qAttached' (query-attached) packet.
3056 set remote read-siginfo-object
3057 show remote read-siginfo-object
3058 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3061 set remote write-siginfo-object
3062 show remote write-siginfo-object
3063 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3066 set remote reverse-continue
3067 show remote reverse-continue
3068 Control use of remote protocol 'bc' (reverse-continue) packet.
3070 set remote reverse-step
3071 show remote reverse-step
3072 Control use of remote protocol 'bs' (reverse-step) packet.
3074 set displaced-stepping
3075 show displaced-stepping
3076 Control displaced stepping mode. Displaced stepping is a way to
3077 single-step over breakpoints without removing them from the debuggee.
3078 Also known as "out-of-line single-stepping".
3081 show debug displaced
3082 Control display of debugging info for displaced stepping.
3084 maint set internal-error
3085 maint show internal-error
3086 Control what GDB does when an internal error is detected.
3088 maint set internal-warning
3089 maint show internal-warning
3090 Control what GDB does when an internal warning is detected.
3095 Use a wrapper program to launch programs for debugging.
3097 set multiple-symbols (all|ask|cancel)
3098 show multiple-symbols
3099 The value of this variable can be changed to adjust the debugger behavior
3100 when an expression or a breakpoint location contains an ambiguous symbol
3101 name (an overloaded function name, for instance).
3103 set breakpoint always-inserted
3104 show breakpoint always-inserted
3105 Keep breakpoints always inserted in the target, as opposed to inserting
3106 them when resuming the target, and removing them when the target stops.
3107 This option can improve debugger performance on slow remote targets.
3109 set arm fallback-mode (arm|thumb|auto)
3110 show arm fallback-mode
3111 set arm force-mode (arm|thumb|auto)
3113 These commands control how ARM GDB determines whether instructions
3114 are ARM or Thumb. The default for both settings is auto, which uses
3115 the current CPSR value for instructions without symbols; previous
3116 versions of GDB behaved as if "set arm fallback-mode arm".
3118 set disable-randomization
3119 show disable-randomization
3120 Standalone programs run with the virtual address space randomization enabled
3121 by default on some platforms. This option keeps the addresses stable across
3122 multiple debugging sessions.
3126 Control whether other threads are stopped or not when some thread hits
3131 Requests that asynchronous execution is enabled in the target, if available.
3132 In this case, it's possible to resume target in the background, and interact
3133 with GDB while the target is running. "show target-async" displays the
3134 current state of asynchronous execution of the target.
3136 set target-wide-charset
3137 show target-wide-charset
3138 The target-wide-charset is the name of the character set that GDB
3139 uses when printing characters whose type is wchar_t.
3141 set tcp auto-retry (on|off)
3143 set tcp connect-timeout
3144 show tcp connect-timeout
3145 These commands allow GDB to retry failed TCP connections to a remote stub
3146 with a specified timeout period; this is useful if the stub is launched
3147 in parallel with GDB but may not be ready to accept connections immediately.
3149 set libthread-db-search-path
3150 show libthread-db-search-path
3151 Control list of directories which GDB will search for appropriate
3154 set schedule-multiple (on|off)
3155 show schedule-multiple
3156 Allow GDB to resume all threads of all processes or only threads of
3157 the current process.
3161 Use more aggressive caching for accesses to the stack. This improves
3162 performance of remote debugging (particularly backtraces) without
3163 affecting correctness.
3165 set interactive-mode (on|off|auto)
3166 show interactive-mode
3167 Control whether GDB runs in interactive mode (on) or not (off).
3168 When in interactive mode, GDB waits for the user to answer all
3169 queries. Otherwise, GDB does not wait and assumes the default
3170 answer. When set to auto (the default), GDB determines which
3171 mode to use based on the stdin settings.
3176 For program forks, this is replaced by the new more generic `info
3177 inferiors' command. To list checkpoints, you can still use the
3178 `info checkpoints' command, which was an alias for the `info forks'
3182 Replaced by the new `inferior' command. To switch between
3183 checkpoints, you can still use the `restart' command, which was an
3184 alias for the `fork' command.
3187 This is removed, since some targets don't have a notion of
3188 processes. To switch between processes, you can still use the
3189 `inferior' command using GDB's own inferior number.
3192 For program forks, this is replaced by the new more generic `kill
3193 inferior' command. To delete a checkpoint, you can still use the
3194 `delete checkpoint' command, which was an alias for the `delete
3198 For program forks, this is replaced by the new more generic `detach
3199 inferior' command. To detach a checkpoint, you can still use the
3200 `detach checkpoint' command, which was an alias for the `detach
3203 * New native configurations
3205 x86/x86_64 Darwin i[34567]86-*-darwin*
3207 x86_64 MinGW x86_64-*-mingw*
3211 Lattice Mico32 lm32-*
3212 x86 DICOS i[34567]86-*-dicos*
3213 x86_64 DICOS x86_64-*-dicos*
3216 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3217 (mingw32ce) debugging.
3223 These commands were actually not implemented on any target.
3225 *** Changes in GDB 6.8
3227 * New native configurations
3229 NetBSD/hppa hppa*-*netbsd*
3230 Xtensa GNU/Linux xtensa*-*-linux*
3234 NetBSD/hppa hppa*-*-netbsd*
3235 Xtensa GNU/Lunux xtensa*-*-linux*
3237 * Change in command line behavior -- corefiles vs. process ids.
3239 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3240 attaching to process NUMBER fails, GDB no longer attempts to open a
3241 core file named NUMBER. Attaching to a program using the -c option
3242 is no longer supported. Instead, use the '-p' or '--pid' options.
3244 * GDB can now be built as a native debugger for debugging Windows x86
3245 (mingw32) Portable Executable (PE) programs.
3247 * Pending breakpoints no longer change their number when their address
3250 * GDB now supports breakpoints with multiple locations,
3251 including breakpoints on C++ constructors, inside C++ templates,
3252 and in inlined functions.
3254 * GDB's ability to debug optimized code has been improved. GDB more
3255 accurately identifies function bodies and lexical blocks that occupy
3256 more than one contiguous range of addresses.
3258 * Target descriptions can now describe registers for PowerPC.
3260 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3261 registers on PowerPC targets.
3263 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3264 targets even when the libthread_db library is not available.
3266 * The GDB remote stub, gdbserver, now supports the new file transfer
3267 commands (remote put, remote get, and remote delete).
3269 * The GDB remote stub, gdbserver, now supports run and attach in
3270 extended-remote mode.
3272 * hppa*64*-*-hpux11* target broken
3273 The debugger is unable to start a program and fails with the following
3274 error: "Error trying to get information about dynamic linker".
3275 The gdb-6.7 release is also affected.
3277 * GDB now supports the --enable-targets= configure option to allow
3278 building a single GDB executable that supports multiple remote
3279 target architectures.
3281 * GDB now supports debugging C and C++ programs which use the
3282 Decimal Floating Point extension. In addition, the PowerPC target
3283 now has a set of pseudo-registers to inspect decimal float values
3284 stored in two consecutive float registers.
3286 * The -break-insert MI command can optionally create pending
3289 * Improved support for debugging Ada
3290 Many improvements to the Ada language support have been made. These
3292 - Better support for Ada2005 interface types
3293 - Improved handling of arrays and slices in general
3294 - Better support for Taft-amendment types
3295 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3297 - Improved command completion in Ada
3300 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3305 set print frame-arguments (all|scalars|none)
3306 show print frame-arguments
3307 The value of this variable can be changed to control which argument
3308 values should be printed by the debugger when displaying a frame.
3313 Transfer files to and from a remote target, and delete remote files.
3320 Transfer files to and from a remote target, and delete remote files.
3322 * New remote packets
3329 Open, close, read, write, and delete files on the remote system.
3332 Attach to an existing process on the remote system, in extended-remote
3336 Run a new process on the remote system, in extended-remote mode.
3338 *** Changes in GDB 6.7
3340 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3341 bfd, libiberty and opcodes, as revealed by static analysis donated by
3342 Coverity, Inc. (http://scan.coverity.com).
3344 * When looking up multiply-defined global symbols, GDB will now prefer the
3345 symbol definition in the current shared library if it was built using the
3346 -Bsymbolic linker option.
3348 * When the Text User Interface (TUI) is not configured, GDB will now
3349 recognize the -tui command-line option and print a message that the TUI
3352 * The GDB remote stub, gdbserver, now has lower overhead for high
3353 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3355 * GDB for MIPS targets now autodetects whether a remote target provides
3356 32-bit or 64-bit register values.
3358 * Support for C++ member pointers has been improved.
3360 * GDB now understands XML target descriptions, which specify the
3361 target's overall architecture. GDB can read a description from
3362 a local file or over the remote serial protocol.
3364 * Vectors of single-byte data use a new integer type which is not
3365 automatically displayed as character or string data.
3367 * The /s format now works with the print command. It displays
3368 arrays of single-byte integers and pointers to single-byte integers
3371 * Target descriptions can now describe target-specific registers,
3372 for architectures which have implemented the support (currently
3373 only ARM, M68K, and MIPS).
3375 * GDB and the GDB remote stub, gdbserver, now support the XScale
3378 * The GDB remote stub, gdbserver, has been updated to support
3379 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3380 has been rewritten to use the standard GDB remote protocol.
3382 * GDB can now step into C++ functions which are called through thunks.
3384 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3386 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3387 layout. It also supports a TextSeg= and DataSeg= response when only
3388 segment base addresses (rather than offsets) are available.
3390 * The /i format now outputs any trailing branch delay slot instructions
3391 immediately following the last instruction within the count specified.
3393 * The GDB remote protocol "T" stop reply packet now supports a
3394 "library" response. Combined with the new "qXfer:libraries:read"
3395 packet, this response allows GDB to debug shared libraries on targets
3396 where the operating system manages the list of loaded libraries (e.g.
3397 Windows and SymbianOS).
3399 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3400 (DLLs) on Windows and Windows CE targets.
3402 * GDB now supports a faster verification that a .debug file matches its binary
3403 according to its build-id signature, if the signature is present.
3409 Enable or disable hardware flow control (RTS/CTS) on the serial port
3410 when debugging using remote targets.
3412 set mem inaccessible-by-default
3413 show mem inaccessible-by-default
3414 If the target supplies a memory map, for instance via the remote
3415 protocol's "qXfer:memory-map:read" packet, setting this variable
3416 prevents GDB from accessing memory outside the memory map. This
3417 is useful for targets with memory mapped registers or which react
3418 badly to accesses of unmapped address space.
3420 set breakpoint auto-hw
3421 show breakpoint auto-hw
3422 If the target supplies a memory map, for instance via the remote
3423 protocol's "qXfer:memory-map:read" packet, setting this variable
3424 lets GDB use hardware breakpoints automatically for memory regions
3425 where it can not use software breakpoints. This covers both the
3426 "break" command and internal breakpoints used for other commands
3427 including "next" and "finish".
3430 catch exception unhandled
3431 Stop the program execution when Ada exceptions are raised.
3434 Stop the program execution when an Ada assertion failed.
3438 Set an alternate system root for target files. This is a more
3439 general version of "set solib-absolute-prefix", which is now
3440 an alias to "set sysroot".
3443 Provide extended SPU facility status information. This set of
3444 commands is available only when debugging the Cell/B.E. SPU
3447 * New native configurations
3449 OpenBSD/sh sh*-*openbsd*
3452 unset tdesc filename
3454 Use the specified local file as an XML target description, and do
3455 not query the target for its built-in description.
3459 OpenBSD/sh sh*-*-openbsd*
3460 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3461 Toshiba Media Processor mep-elf
3463 * New remote packets
3466 Ignore the specified signals; pass them directly to the debugged program
3467 without stopping other threads or reporting them to GDB.
3469 qXfer:features:read:
3470 Read an XML target description from the target, which describes its
3475 Read or write contents of an spufs file on the target system. These
3476 packets are available only on the Cell/B.E. SPU architecture.
3478 qXfer:libraries:read:
3479 Report the loaded shared libraries. Combined with new "T" packet
3480 response, this packet allows GDB to debug shared libraries on
3481 targets where the operating system manages the list of loaded
3482 libraries (e.g. Windows and SymbianOS).
3486 Support for these obsolete configurations has been removed.
3494 i[34567]86-*-lynxos*
3495 i[34567]86-*-netware*
3496 i[34567]86-*-sco3.2v5*
3497 i[34567]86-*-sco3.2v4*
3499 i[34567]86-*-sysv4.2*
3502 i[34567]86-*-unixware2*
3503 i[34567]86-*-unixware*
3512 * Other removed features
3519 Various m68k-only ROM monitors.
3526 Various Renesas ROM monitors and debugging interfaces for SH and
3531 Support for a Macraigor serial interface to on-chip debugging.
3532 GDB does not directly support the newer parallel or USB
3537 A debug information format. The predecessor to DWARF 2 and
3538 DWARF 3, which are still supported.
3540 Support for the HP aCC compiler on HP-UX/PA-RISC
3542 SOM-encapsulated symbolic debugging information, automatic
3543 invocation of pxdb, and the aCC custom C++ ABI. This does not
3544 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3545 with aCC can still be debugged on an assembly level.
3547 MIPS ".pdr" sections
3549 A MIPS-specific format used to describe stack frame layout
3550 in debugging information.
3554 GDB could work with an older version of Guile to debug
3555 the interpreter and Scheme programs running in it.
3557 set mips stack-arg-size
3558 set mips saved-gpreg-size
3560 Use "set mips abi" to control parameter passing for MIPS.
3562 *** Changes in GDB 6.6
3567 Cell Broadband Engine SPU spu-elf
3569 * GDB can now be configured as a cross-debugger targeting native Windows
3570 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3571 running on a Windows system over TCP/IP to debug Windows programs.
3573 * The GDB remote stub, gdbserver, has been updated to support Windows and
3574 Cygwin debugging. Both single-threaded and multi-threaded programs are
3577 * The "set trust-readonly-sections" command works again. This command was
3578 broken in GDB 6.3, 6.4, and 6.5.
3580 * The "load" command now supports writing to flash memory, if the remote
3581 stub provides the required support.
3583 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3584 longer requires symbolic debug information (e.g. DWARF-2).
3589 unset substitute-path
3590 show substitute-path
3591 Manage a list of substitution rules that GDB uses to rewrite the name
3592 of the directories where the sources are located. This can be useful
3593 for instance when the sources were moved to a different location
3594 between compilation and debugging.
3598 Print each CLI command as it is executed. Each command is prefixed with
3599 a number of `+' symbols representing the nesting depth.
3600 The source command now has a `-v' option to enable the same feature.
3604 The ARM Demon monitor support (RDP protocol, "target rdp").
3606 Kernel Object Display, an embedded debugging feature which only worked with
3607 an obsolete version of Cisco IOS.
3609 The 'set download-write-size' and 'show download-write-size' commands.
3611 * New remote packets
3614 Tell a stub about GDB client features, and request remote target features.
3615 The first feature implemented is PacketSize, which allows the target to
3616 specify the size of packets it can handle - to minimize the number of
3617 packets required and improve performance when connected to a remote
3621 Fetch an OS auxilliary vector from the remote stub. This packet is a
3622 more efficient replacement for qPart:auxv:read.
3624 qXfer:memory-map:read:
3625 Fetch a memory map from the remote stub, including information about
3626 RAM, ROM, and flash memory devices.
3631 Erase and program a flash memory device.
3633 * Removed remote packets
3636 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3637 used it, and only gdbserver implemented it.
3639 *** Changes in GDB 6.5
3643 Renesas M32C/M16C m32c-elf
3645 Morpho Technologies ms1 ms1-elf
3649 init-if-undefined Initialize a convenience variable, but
3650 only if it doesn't already have a value.
3652 The following commands are presently only implemented for native GNU/Linux:
3654 checkpoint Save a snapshot of the program state.
3656 restart <n> Return the program state to a
3657 previously saved state.
3659 info checkpoints List currently saved checkpoints.
3661 delete-checkpoint <n> Delete a previously saved checkpoint.
3663 set|show detach-on-fork Tell gdb whether to detach from a newly
3664 forked process, or to keep debugging it.
3666 info forks List forks of the user program that
3667 are available to be debugged.
3669 fork <n> Switch to debugging one of several
3670 forks of the user program that are
3671 available to be debugged.
3673 delete-fork <n> Delete a fork from the list of forks
3674 that are available to be debugged (and
3675 kill the forked process).
3677 detach-fork <n> Delete a fork from the list of forks
3678 that are available to be debugged (and
3679 allow the process to continue).
3683 Morpho Technologies ms2 ms1-elf
3685 * Improved Windows host support
3687 GDB now builds as a cross debugger hosted on i686-mingw32, including
3688 native console support, and remote communications using either
3689 network sockets or serial ports.
3691 * Improved Modula-2 language support
3693 GDB can now print most types in the Modula-2 syntax. This includes:
3694 basic types, set types, record types, enumerated types, range types,
3695 pointer types and ARRAY types. Procedure var parameters are correctly
3696 printed and hexadecimal addresses and character constants are also
3697 written in the Modula-2 syntax. Best results can be obtained by using
3698 GNU Modula-2 together with the -gdwarf-2 command line option.
3702 The ARM rdi-share module.
3704 The Netware NLM debug server.
3706 *** Changes in GDB 6.4
3708 * New native configurations
3710 OpenBSD/arm arm*-*-openbsd*
3711 OpenBSD/mips64 mips64-*-openbsd*
3715 Morpho Technologies ms1 ms1-elf
3717 * New command line options
3719 --batch-silent As for --batch, but totally silent.
3720 --return-child-result The debugger will exist with the same value
3721 the child (debugged) program exited with.
3722 --eval-command COMMAND, -ex COMMAND
3723 Execute a single GDB CLI command. This may be
3724 specified multiple times and in conjunction
3725 with the --command (-x) option.
3727 * Deprecated commands removed
3729 The following commands, that were deprecated in 2000, have been
3733 set|show arm disassembly-flavor set|show arm disassembler
3734 othernames set arm disassembler
3735 set|show remotedebug set|show debug remote
3736 set|show archdebug set|show debug arch
3737 set|show eventdebug set|show debug event
3740 * New BSD user-level threads support
3742 It is now possible to debug programs using the user-level threads
3743 library on OpenBSD and FreeBSD. Currently supported (target)
3746 FreeBSD/amd64 x86_64-*-freebsd*
3747 FreeBSD/i386 i386-*-freebsd*
3748 OpenBSD/i386 i386-*-openbsd*
3750 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3751 are not yet supported.
3753 * New support for Matsushita MN10300 w/sim added
3754 (Work in progress). mn10300-elf.
3756 * REMOVED configurations and files
3758 VxWorks and the XDR protocol *-*-vxworks
3759 Motorola MCORE mcore-*-*
3760 National Semiconductor NS32000 ns32k-*-*
3762 * New "set print array-indexes" command
3764 After turning this setting "on", GDB prints the index of each element
3765 when displaying arrays. The default is "off" to preserve the previous
3768 * VAX floating point support
3770 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3772 * User-defined command support
3774 In addition to using $arg0..$arg9 for argument passing, it is now possible
3775 to use $argc to determine now many arguments have been passed. See the
3776 section on user-defined commands in the user manual for more information.
3778 *** Changes in GDB 6.3:
3780 * New command line option
3782 GDB now accepts -l followed by a number to set the timeout for remote
3785 * GDB works with GCC -feliminate-dwarf2-dups
3787 GDB now supports a more compact representation of DWARF-2 debug
3788 information using DW_FORM_ref_addr references. These are produced
3789 by GCC with the option -feliminate-dwarf2-dups and also by some
3790 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3791 to use -feliminate-dwarf2-dups.
3793 * Internationalization
3795 When supported by the host system, GDB will be built with
3796 internationalization (libintl). The task of marking up the sources is
3797 continued, we're looking forward to our first translation.
3801 Initial support for debugging programs compiled with the GNAT
3802 implementation of the Ada programming language has been integrated
3803 into GDB. In this release, support is limited to expression evaluation.
3805 * New native configurations
3807 GNU/Linux/m32r m32r-*-linux-gnu
3811 GDB's remote protocol now includes support for the 'p' packet. This
3812 packet is used to fetch individual registers from a remote inferior.
3814 * END-OF-LIFE registers[] compatibility module
3816 GDB's internal register infrastructure has been completely rewritten.
3817 The new infrastructure making possible the implementation of key new
3818 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3821 GDB 6.3 will be the last release to include the the registers[]
3822 compatibility module that allowed out-of-date configurations to
3823 continue to work. This change directly impacts the following
3833 powerpc bdm protocol
3835 Unless there is activity to revive these configurations, they will be
3836 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3838 * OBSOLETE configurations and files
3840 Configurations that have been declared obsolete in this release have
3841 been commented out. Unless there is activity to revive these
3842 configurations, the next release of GDB will have their sources
3843 permanently REMOVED.
3852 *** Changes in GDB 6.2.1:
3854 * MIPS `break main; run' gave an heuristic-fence-post warning
3856 When attempting to run even a simple program, a warning about
3857 heuristic-fence-post being hit would be reported. This problem has
3860 * MIPS IRIX 'long double' crashed GDB
3862 When examining a long double variable, GDB would get a segmentation
3863 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3864 IRIX long double values).
3868 A bug in the VAX stack code was causing problems with the "next"
3869 command. This problem has been fixed.
3871 *** Changes in GDB 6.2:
3873 * Fix for ``many threads''
3875 On GNU/Linux systems that use the NPTL threads library, a program
3876 rapidly creating and deleting threads would confuse GDB leading to the
3879 ptrace: No such process.
3880 thread_db_get_info: cannot get thread info: generic error
3882 This problem has been fixed.
3884 * "-async" and "-noasync" options removed.
3886 Support for the broken "-noasync" option has been removed (it caused
3889 * New ``start'' command.
3891 This command runs the program until the begining of the main procedure.
3893 * New BSD Kernel Data Access Library (libkvm) interface
3895 Using ``target kvm'' it is now possible to debug kernel core dumps and
3896 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3897 platforms. Currently supported (native-only) configurations are:
3899 FreeBSD/amd64 x86_64-*-freebsd*
3900 FreeBSD/i386 i?86-*-freebsd*
3901 NetBSD/i386 i?86-*-netbsd*
3902 NetBSD/m68k m68*-*-netbsd*
3903 NetBSD/sparc sparc-*-netbsd*
3904 OpenBSD/amd64 x86_64-*-openbsd*
3905 OpenBSD/i386 i?86-*-openbsd*
3906 OpenBSD/m68k m68*-openbsd*
3907 OpenBSD/sparc sparc-*-openbsd*
3909 * Signal trampoline code overhauled
3911 Many generic problems with GDB's signal handling code have been fixed.
3912 These include: backtraces through non-contiguous stacks; recognition
3913 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3914 call; backtrace through a signal trampoline; step into and out of
3915 signal handlers; and single-stepping in the signal trampoline.
3917 Please note that kernel bugs are a limiting factor here. These
3918 features have been shown to work on an s390 GNU/Linux system that
3919 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3921 * Cygwin support for DWARF 2 added.
3923 * New native configurations
3925 GNU/Linux/hppa hppa*-*-linux*
3926 OpenBSD/hppa hppa*-*-openbsd*
3927 OpenBSD/m68k m68*-*-openbsd*
3928 OpenBSD/m88k m88*-*-openbsd*
3929 OpenBSD/powerpc powerpc-*-openbsd*
3930 NetBSD/vax vax-*-netbsd*
3931 OpenBSD/vax vax-*-openbsd*
3933 * END-OF-LIFE frame compatibility module
3935 GDB's internal frame infrastructure has been completely rewritten.
3936 The new infrastructure making it possible to support key new features
3937 including DWARF 2 Call Frame Information. To aid in the task of
3938 migrating old configurations to this new infrastructure, a
3939 compatibility module, that allowed old configurations to continue to
3940 work, was also included.
3942 GDB 6.2 will be the last release to include this frame compatibility
3943 module. This change directly impacts the following configurations:
3953 Unless there is activity to revive these configurations, they will be
3954 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3956 * REMOVED configurations and files
3958 Sun 3, running SunOS 3 m68*-*-sunos3*
3959 Sun 3, running SunOS 4 m68*-*-sunos4*
3960 Sun 2, running SunOS 3 m68000-*-sunos3*
3961 Sun 2, running SunOS 4 m68000-*-sunos4*
3962 Motorola 680x0 running LynxOS m68*-*-lynxos*
3963 AT&T 3b1/Unix pc m68*-att-*
3964 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3965 decstation mips-dec-* mips-little-*
3966 riscos mips-*-riscos* mips-*-sysv*
3967 sonymips mips-sony-*
3968 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3970 *** Changes in GDB 6.1.1:
3972 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3974 The TUI (Text-mode User Interface) is now built as part of a default
3975 GDB configuration. It is enabled by either selecting the TUI with the
3976 command line option "-i=tui" or by running the separate "gdbtui"
3977 program. For more information on the TUI, see the manual "Debugging
3980 * Pending breakpoint support (also included in GDB 6.1)
3982 Support has been added to allow you to specify breakpoints in shared
3983 libraries that have not yet been loaded. If a breakpoint location
3984 cannot be found, and the "breakpoint pending" option is set to auto,
3985 GDB queries you if you wish to make the breakpoint pending on a future
3986 shared-library load. If and when GDB resolves the breakpoint symbol,
3987 the pending breakpoint is removed as one or more regular breakpoints
3990 Pending breakpoints are very useful for GCJ Java debugging.
3992 * Fixed ISO-C build problems
3994 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3995 non ISO-C code that stopped them being built using a more strict ISO-C
3996 compiler (e.g., IBM's C compiler).
3998 * Fixed build problem on IRIX 5
4000 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4001 wasn't able to compile compile on an IRIX 5 system.
4003 * Added execute permission to gdb/gdbserver/configure
4005 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4006 permission. This bug would cause configure to fail on a number of
4007 systems (Solaris, IRIX). Ref: server/519.
4009 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4011 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4012 has been updated to use constant array sizes.
4014 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4016 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4017 its generated DWARF Call Frame Info. This encoding was causing GDB to
4018 panic, that panic has been fixed. Ref: gdb/1628.
4020 * Fixed a problem when examining parameters in shared library code.
4022 When examining parameters in optimized shared library code generated
4023 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4024 not available''. GDB now correctly displays the variable's value.
4026 *** Changes in GDB 6.1:
4028 * Removed --with-mmalloc
4030 Support for the mmalloc memory manager has been removed, as it
4031 conflicted with the internal gdb byte cache.
4033 * Changes in AMD64 configurations
4035 The AMD64 target now includes the %cs and %ss registers. As a result
4036 the AMD64 remote protocol has changed; this affects the floating-point
4037 and SSE registers. If you rely on those registers for your debugging,
4038 you should upgrade gdbserver on the remote side.
4040 * Revised SPARC target
4042 The SPARC target has been completely revised, incorporating the
4043 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4044 support for LynxOS and SunOS 4 has been dropped. Calling functions
4045 from within GDB on operating systems with a non-executable stack
4046 (Solaris, OpenBSD) now works.
4050 GDB has a new C++ demangler which does a better job on the mangled
4051 names generated by current versions of g++. It also runs faster, so
4052 with this and other changes gdb should now start faster on large C++
4055 * DWARF 2 Location Expressions
4057 GDB support for location expressions has been extended to support function
4058 arguments and frame bases. Older versions of GDB could crash when they
4061 * C++ nested types and namespaces
4063 GDB's support for nested types and namespaces in C++ has been
4064 improved, especially if you use the DWARF 2 debugging format. (This
4065 is the default for recent versions of GCC on most platforms.)
4066 Specifically, if you have a class "Inner" defined within a class or
4067 namespace "Outer", then GDB realizes that the class's name is
4068 "Outer::Inner", not simply "Inner". This should greatly reduce the
4069 frequency of complaints about not finding RTTI symbols. In addition,
4070 if you are stopped at inside of a function defined within a namespace,
4071 GDB modifies its name lookup accordingly.
4073 * New native configurations
4075 NetBSD/amd64 x86_64-*-netbsd*
4076 OpenBSD/amd64 x86_64-*-openbsd*
4077 OpenBSD/alpha alpha*-*-openbsd*
4078 OpenBSD/sparc sparc-*-openbsd*
4079 OpenBSD/sparc64 sparc64-*-openbsd*
4081 * New debugging protocols
4083 M32R with SDI protocol m32r-*-elf*
4085 * "set prompt-escape-char" command deleted.
4087 The command "set prompt-escape-char" has been deleted. This command,
4088 and its very obscure effet on GDB's prompt, was never documented,
4089 tested, nor mentioned in the NEWS file.
4091 * OBSOLETE configurations and files
4093 Configurations that have been declared obsolete in this release have
4094 been commented out. Unless there is activity to revive these
4095 configurations, the next release of GDB will have their sources
4096 permanently REMOVED.
4098 Sun 3, running SunOS 3 m68*-*-sunos3*
4099 Sun 3, running SunOS 4 m68*-*-sunos4*
4100 Sun 2, running SunOS 3 m68000-*-sunos3*
4101 Sun 2, running SunOS 4 m68000-*-sunos4*
4102 Motorola 680x0 running LynxOS m68*-*-lynxos*
4103 AT&T 3b1/Unix pc m68*-att-*
4104 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4105 decstation mips-dec-* mips-little-*
4106 riscos mips-*-riscos* mips-*-sysv*
4107 sonymips mips-sony-*
4108 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4110 * REMOVED configurations and files
4112 SGI Irix-4.x mips-sgi-irix4 or iris4
4113 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4114 Z8000 simulator z8k-zilog-none or z8ksim
4115 Matsushita MN10200 w/simulator mn10200-*-*
4116 H8/500 simulator h8500-hitachi-hms or h8500hms
4117 HP/PA running BSD hppa*-*-bsd*
4118 HP/PA running OSF/1 hppa*-*-osf*
4119 HP/PA Pro target hppa*-*-pro*
4120 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4121 386BSD i[3456]86-*-bsd*
4122 Sequent family i[3456]86-sequent-sysv4*
4123 i[3456]86-sequent-sysv*
4124 i[3456]86-sequent-bsd*
4125 SPARC running LynxOS sparc-*-lynxos*
4126 SPARC running SunOS 4 sparc-*-sunos4*
4127 Tsqware Sparclet sparclet-*-*
4128 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4130 *** Changes in GDB 6.0:
4134 Support for debugging the Objective-C programming language has been
4135 integrated into GDB.
4137 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4139 DWARF 2's Call Frame Information makes available compiler generated
4140 information that more exactly describes the program's run-time stack.
4141 By using this information, GDB is able to provide more robust stack
4144 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4145 have been updated to use a new backtrace mechanism which includes
4146 DWARF 2 CFI support.
4150 GDB's remote protocol has been extended to include support for hosted
4151 file I/O (where the remote target uses GDB's file system). See GDB's
4152 remote protocol documentation for details.
4154 * All targets using the new architecture framework.
4156 All of GDB's targets have been updated to use the new internal
4157 architecture framework. The way is now open for future GDB releases
4158 to include cross-architecture native debugging support (i386 on amd64,
4161 * GNU/Linux's Thread Local Storage (TLS)
4163 GDB now includes support for for the GNU/Linux implementation of
4164 per-thread variables.
4166 * GNU/Linux's Native POSIX Thread Library (NPTL)
4168 GDB's thread code has been updated to work with either the new
4169 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4171 * Separate debug info.
4173 GDB, in conjunction with BINUTILS, now supports a mechanism for
4174 automatically loading debug information from a separate file. Instead
4175 of shipping full debug and non-debug versions of system libraries,
4176 system integrators can now instead ship just the stripped libraries
4177 and optional debug files.
4179 * DWARF 2 Location Expressions
4181 DWARF 2 Location Expressions allow the compiler to more completely
4182 describe the location of variables (even in optimized code) to the
4185 GDB now includes preliminary support for location expressions (support
4186 for DW_OP_piece is still missing).
4190 A number of long standing bugs that caused GDB to die while starting a
4191 Java application have been fixed. GDB's Java support is now
4192 considered "useable".
4194 * GNU/Linux support for fork, vfork, and exec.
4196 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4197 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4200 * GDB supports logging output to a file
4202 There are two new commands, "set logging" and "show logging", which can be
4203 used to capture GDB's output to a file.
4205 * The meaning of "detach" has changed for gdbserver
4207 The "detach" command will now resume the application, as documented. To
4208 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4211 * d10v, m68hc11 `regs' command deprecated
4213 The `info registers' command has been updated so that it displays the
4214 registers using a format identical to the old `regs' command.
4218 A new command, "maint set profile on/off", has been added. This command can
4219 be used to enable or disable profiling while running GDB, to profile a
4220 session or a set of commands. In addition there is a new configure switch,
4221 "--enable-profiling", which will cause GDB to be compiled with profiling
4222 data, for more informative profiling results.
4224 * Default MI syntax changed to "mi2".
4226 The default MI (machine interface) syntax, enabled by the command line
4227 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4228 "mi1", can be enabled by specifying the option "-i=mi1".
4230 Support for the original "mi0" syntax (included in GDB 5.0) has been
4233 Fix for gdb/192: removed extraneous space when displaying frame level.
4234 Fix for gdb/672: update changelist is now output in mi list format.
4235 Fix for gdb/702: a -var-assign that updates the value now shows up
4236 in a subsequent -var-update.
4238 * New native configurations.
4240 FreeBSD/amd64 x86_64-*-freebsd*
4242 * Multi-arched targets.
4244 HP/PA HPUX11 hppa*-*-hpux*
4245 Renesas M32R/D w/simulator m32r-*-elf*
4247 * OBSOLETE configurations and files
4249 Configurations that have been declared obsolete in this release have
4250 been commented out. Unless there is activity to revive these
4251 configurations, the next release of GDB will have their sources
4252 permanently REMOVED.
4254 Z8000 simulator z8k-zilog-none or z8ksim
4255 Matsushita MN10200 w/simulator mn10200-*-*
4256 H8/500 simulator h8500-hitachi-hms or h8500hms
4257 HP/PA running BSD hppa*-*-bsd*
4258 HP/PA running OSF/1 hppa*-*-osf*
4259 HP/PA Pro target hppa*-*-pro*
4260 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4261 Sequent family i[3456]86-sequent-sysv4*
4262 i[3456]86-sequent-sysv*
4263 i[3456]86-sequent-bsd*
4264 Tsqware Sparclet sparclet-*-*
4265 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4267 * REMOVED configurations and files
4270 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4271 IBM AIX PS/2 i[3456]86-*-aix
4272 i386 running Mach 3.0 i[3456]86-*-mach3*
4273 i386 running Mach i[3456]86-*-mach*
4274 i386 running OSF/1 i[3456]86-*osf1mk*
4275 HP/Apollo 68k Family m68*-apollo*-sysv*,
4277 m68*-hp-bsd*, m68*-hp-hpux*
4278 Argonaut Risc Chip (ARC) arc-*-*
4279 Mitsubishi D30V d30v-*-*
4280 Fujitsu FR30 fr30-*-elf*
4281 OS/9000 i[34]86-*-os9k
4282 I960 with MON960 i960-*-coff
4284 * MIPS $fp behavior changed
4286 The convenience variable $fp, for the MIPS, now consistently returns
4287 the address of the current frame's base. Previously, depending on the
4288 context, $fp could refer to either $sp or the current frame's base
4289 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4290 The GNU Source-Level Debugger''.
4292 *** Changes in GDB 5.3:
4294 * GNU/Linux shared library multi-threaded performance improved.
4296 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4297 `/proc', in preference to `ptrace' for memory reads. This may result
4298 in an improvement in the start-up time of multi-threaded, shared
4299 library applications when run under GDB. One GDB user writes: ``loads
4300 shared libs like mad''.
4302 * ``gdbserver'' now supports multi-threaded applications on some targets
4304 Support for debugging multi-threaded applications which use
4305 the GNU/Linux LinuxThreads package has been added for
4306 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4307 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4309 * GDB now supports C/C++ preprocessor macros.
4311 GDB now expands preprocessor macro invocations in C/C++ expressions,
4312 and provides various commands for showing macro definitions and how
4315 The new command `macro expand EXPRESSION' expands any macro
4316 invocations in expression, and shows the result.
4318 The new command `show macro MACRO-NAME' shows the definition of the
4319 macro named MACRO-NAME, and where it was defined.
4321 Most compilers don't include information about macros in the debugging
4322 information by default. In GCC 3.1, for example, you need to compile
4323 your program with the options `-gdwarf-2 -g3'. If the macro
4324 information is present in the executable, GDB will read it.
4326 * Multi-arched targets.
4328 DEC Alpha (partial) alpha*-*-*
4329 DEC VAX (partial) vax-*-*
4331 National Semiconductor NS32000 (partial) ns32k-*-*
4332 Motorola 68000 (partial) m68k-*-*
4333 Motorola MCORE mcore-*-*
4337 Fujitsu FRV architecture added by Red Hat frv*-*-*
4340 * New native configurations
4342 Alpha NetBSD alpha*-*-netbsd*
4343 SH NetBSD sh*-*-netbsdelf*
4344 MIPS NetBSD mips*-*-netbsd*
4345 UltraSPARC NetBSD sparc64-*-netbsd*
4347 * OBSOLETE configurations and files
4349 Configurations that have been declared obsolete in this release have
4350 been commented out. Unless there is activity to revive these
4351 configurations, the next release of GDB will have their sources
4352 permanently REMOVED.
4354 Mitsubishi D30V d30v-*-*
4355 OS/9000 i[34]86-*-os9k
4356 IBM AIX PS/2 i[3456]86-*-aix
4357 Fujitsu FR30 fr30-*-elf*
4358 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4359 Argonaut Risc Chip (ARC) arc-*-*
4360 i386 running Mach 3.0 i[3456]86-*-mach3*
4361 i386 running Mach i[3456]86-*-mach*
4362 i386 running OSF/1 i[3456]86-*osf1mk*
4363 HP/Apollo 68k Family m68*-apollo*-sysv*,
4365 m68*-hp-bsd*, m68*-hp-hpux*
4366 I960 with MON960 i960-*-coff
4368 * OBSOLETE languages
4370 CHILL, a Pascal like language used by telecommunications companies.
4372 * REMOVED configurations and files
4374 AMD 29k family via UDI a29k-amd-udi, udi29k
4375 A29K VxWorks a29k-*-vxworks
4376 AMD 29000 embedded, using EBMON a29k-none-none
4377 AMD 29000 embedded with COFF a29k-none-coff
4378 AMD 29000 embedded with a.out a29k-none-aout
4380 testsuite/gdb.hp/gdb.threads-hp/ directory
4382 * New command "set max-user-call-depth <nnn>"
4384 This command allows the user to limit the call depth of user-defined
4385 commands. The default is 1024.
4387 * Changes in FreeBSD/i386 native debugging.
4389 Support for the "generate-core-file" has been added.
4391 * New commands "dump", "append", and "restore".
4393 These commands allow data to be copied from target memory
4394 to a bfd-format or binary file (dump and append), and back
4395 from a file into memory (restore).
4397 * Improved "next/step" support on multi-processor Alpha Tru64.
4399 The previous single-step mechanism could cause unpredictable problems,
4400 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4401 of a software single-step mechanism prevents this.
4403 *** Changes in GDB 5.2.1:
4411 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4412 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4413 Fix, by Joel Brobecker imported from mainline.
4415 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4416 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4417 Fix, by Fred Fish, imported from mainline.
4419 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4420 Surprisingly enough, it works now.
4421 By Michal Ludvig, imported from mainline.
4423 i386 hardware watchpoint support:
4424 avoid misses on second run for some targets.
4425 By Pierre Muller, imported from mainline.
4427 *** Changes in GDB 5.2:
4429 * New command "set trust-readonly-sections on[off]".
4431 This command is a hint that tells gdb that read-only sections
4432 really are read-only (ie. that their contents will not change).
4433 In this mode, gdb will go to the object file rather than the
4434 target to read memory from read-only sections (such as ".text").
4435 This can be a significant performance improvement on some
4436 (notably embedded) targets.
4438 * New command "generate-core-file" (or "gcore").
4440 This new gdb command allows the user to drop a core file of the child
4441 process state at any time. So far it's been implemented only for
4442 GNU/Linux and Solaris, but should be relatively easily ported to other
4443 hosts. Argument is core file name (defaults to core.<pid>).
4445 * New command line option
4447 GDB now accepts --pid or -p followed by a process id.
4449 * Change in command line behavior -- corefiles vs. process ids.
4451 There is a subtle behavior in the way in which GDB handles
4452 command line arguments. The first non-flag argument is always
4453 a program to debug, but the second non-flag argument may either
4454 be a corefile or a process id. Previously, GDB would attempt to
4455 open the second argument as a corefile, and if that failed, would
4456 issue a superfluous error message and then attempt to attach it as
4457 a process. Now, if the second argument begins with a non-digit,
4458 it will be treated as a corefile. If it begins with a digit,
4459 GDB will attempt to attach it as a process, and if no such process
4460 is found, will then attempt to open it as a corefile.
4462 * Changes in ARM configurations.
4464 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4465 configuration is fully multi-arch.
4467 * New native configurations
4469 ARM NetBSD arm*-*-netbsd*
4470 x86 OpenBSD i[3456]86-*-openbsd*
4471 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4472 Sparc64 running FreeBSD sparc64-*-freebsd*
4476 Sanyo XStormy16 xstormy16-elf
4478 * OBSOLETE configurations and files
4480 Configurations that have been declared obsolete in this release have
4481 been commented out. Unless there is activity to revive these
4482 configurations, the next release of GDB will have their sources
4483 permanently REMOVED.
4485 AMD 29k family via UDI a29k-amd-udi, udi29k
4486 A29K VxWorks a29k-*-vxworks
4487 AMD 29000 embedded, using EBMON a29k-none-none
4488 AMD 29000 embedded with COFF a29k-none-coff
4489 AMD 29000 embedded with a.out a29k-none-aout
4491 testsuite/gdb.hp/gdb.threads-hp/ directory
4493 * REMOVED configurations and files
4495 TI TMS320C80 tic80-*-*
4497 PowerPC Solaris powerpcle-*-solaris*
4498 PowerPC Windows NT powerpcle-*-cygwin32
4499 PowerPC Netware powerpc-*-netware*
4500 Harris/CXUX m88k m88*-harris-cxux*
4501 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4502 ns32k-utek-sysv* ns32k-utek-*
4503 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4504 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4505 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4506 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4507 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4509 * Changes to command line processing
4511 The new `--args' feature can be used to specify command-line arguments
4512 for the inferior from gdb's command line.
4514 * Changes to key bindings
4516 There is a new `operate-and-get-next' function bound to `C-o'.
4518 *** Changes in GDB 5.1.1
4520 Fix compile problem on DJGPP.
4522 Fix a problem with floating-point registers on the i386 being
4525 Fix to stop GDB crashing on .debug_str debug info.
4527 Numerous documentation fixes.
4529 Numerous testsuite fixes.
4531 *** Changes in GDB 5.1:
4533 * New native configurations
4535 Alpha FreeBSD alpha*-*-freebsd*
4536 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4537 MIPS GNU/Linux mips*-*-linux*
4538 MIPS SGI Irix 6.x mips*-sgi-irix6*
4539 ia64 AIX ia64-*-aix*
4540 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4544 Motorola 68HC11 and 68HC12 m68hc11-elf
4546 UltraSparc running GNU/Linux sparc64-*-linux*
4548 * OBSOLETE configurations and files
4550 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4551 Harris/CXUX m88k m88*-harris-cxux*
4552 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4553 ns32k-utek-sysv* ns32k-utek-*
4554 TI TMS320C80 tic80-*-*
4556 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4557 PowerPC Solaris powerpcle-*-solaris*
4558 PowerPC Windows NT powerpcle-*-cygwin32
4559 PowerPC Netware powerpc-*-netware*
4560 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4561 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4562 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4563 Apple Macintosh (MPW) host N/A
4565 stuff.c (Program to stuff files into a specially prepared space in kdb)
4566 kdb-start.c (Main loop for the standalone kernel debugger)
4568 Configurations that have been declared obsolete in this release have
4569 been commented out. Unless there is activity to revive these
4570 configurations, the next release of GDB will have their sources
4571 permanently REMOVED.
4573 * REMOVED configurations and files
4575 Altos 3068 m68*-altos-*
4576 Convex c1-*-*, c2-*-*
4578 ARM RISCix arm-*-* (as host)
4582 * GDB has been converted to ISO C.
4584 GDB's source code has been converted to ISO C. In particular, the
4585 sources are fully protoized, and rely on standard headers being
4590 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4592 * The MI enabled by default.
4594 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4595 revised and enabled by default. Packages which use GDB as a debugging
4596 engine behind a UI or another front end are encouraged to switch to
4597 using the GDB/MI interface, instead of the old annotations interface
4598 which is now deprecated.
4600 * Support for debugging Pascal programs.
4602 GDB now includes support for debugging Pascal programs. The following
4603 main features are supported:
4605 - Pascal-specific data types such as sets;
4607 - automatic recognition of Pascal sources based on file-name
4610 - Pascal-style display of data types, variables, and functions;
4612 - a Pascal expression parser.
4614 However, some important features are not yet supported.
4616 - Pascal string operations are not supported at all;
4618 - there are some problems with boolean types;
4620 - Pascal type hexadecimal constants are not supported
4621 because they conflict with the internal variables format;
4623 - support for Pascal objects and classes is not full yet;
4625 - unlike Pascal, GDB is case-sensitive for symbol names.
4627 * Changes in completion.
4629 Commands such as `shell', `run' and `set args', which pass arguments
4630 to inferior programs, now complete on file names, similar to what
4631 users expect at the shell prompt.
4633 Commands which accept locations, such as `disassemble', `print',
4634 `breakpoint', `until', etc. now complete on filenames as well as
4635 program symbols. Thus, if you type "break foob TAB", and the source
4636 files linked into the programs include `foobar.c', that file name will
4637 be one of the candidates for completion. However, file names are not
4638 considered for completion after you typed a colon that delimits a file
4639 name from a name of a function in that file, as in "break foo.c:bar".
4641 `set demangle-style' completes on available demangling styles.
4643 * New platform-independent commands:
4645 It is now possible to define a post-hook for a command as well as a
4646 hook that runs before the command. For more details, see the
4647 documentation of `hookpost' in the GDB manual.
4649 * Changes in GNU/Linux native debugging.
4651 Support for debugging multi-threaded programs has been completely
4652 revised for all platforms except m68k and sparc. You can now debug as
4653 many threads as your system allows you to have.
4655 Attach/detach is supported for multi-threaded programs.
4657 Support for SSE registers was added for x86. This doesn't work for
4658 multi-threaded programs though.
4660 * Changes in MIPS configurations.
4662 Multi-arch support is enabled for all MIPS configurations.
4664 GDB can now be built as native debugger on SGI Irix 6.x systems for
4665 debugging n32 executables. (Debugging 64-bit executables is not yet
4668 * Unified support for hardware watchpoints in all x86 configurations.
4670 Most (if not all) native x86 configurations support hardware-assisted
4671 breakpoints and watchpoints in a unified manner. This support
4672 implements debug register sharing between watchpoints, which allows to
4673 put a virtually infinite number of watchpoints on the same address,
4674 and also supports watching regions up to 16 bytes with several debug
4677 The new maintenance command `maintenance show-debug-regs' toggles
4678 debugging print-outs in functions that insert, remove, and test
4679 watchpoints and hardware breakpoints.
4681 * Changes in the DJGPP native configuration.
4683 New command ``info dos sysinfo'' displays assorted information about
4684 the CPU, OS, memory, and DPMI server.
4686 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4687 display information about segment descriptors stored in GDT, LDT, and
4690 New commands ``info dos pde'' and ``info dos pte'' display entries
4691 from Page Directory and Page Tables (for now works with CWSDPMI only).
4692 New command ``info dos address-pte'' displays the Page Table entry for
4693 a given linear address.
4695 GDB can now pass command lines longer than 126 characters to the
4696 program being debugged (requires an update to the libdbg.a library
4697 which is part of the DJGPP development kit).
4699 DWARF2 debug info is now supported.
4701 It is now possible to `step' and `next' through calls to `longjmp'.
4703 * Changes in documentation.
4705 All GDB documentation was converted to GFDL, the GNU Free
4706 Documentation License.
4708 Tracepoints-related commands are now fully documented in the GDB
4711 TUI, the Text-mode User Interface, is now documented in the manual.
4713 Tracepoints-related commands are now fully documented in the GDB
4716 The "GDB Internals" manual now has an index. It also includes
4717 documentation of `ui_out' functions, GDB coding standards, x86
4718 hardware watchpoints, and memory region attributes.
4720 * GDB's version number moved to ``version.in''
4722 The Makefile variable VERSION has been replaced by the file
4723 ``version.in''. People creating GDB distributions should update the
4724 contents of this file.
4728 GUD support is now a standard part of the EMACS distribution.
4730 *** Changes in GDB 5.0:
4732 * Improved support for debugging FP programs on x86 targets
4734 Unified and much-improved support for debugging floating-point
4735 programs on all x86 targets. In particular, ``info float'' now
4736 displays the FP registers in the same format on all x86 targets, with
4737 greater level of detail.
4739 * Improvements and bugfixes in hardware-assisted watchpoints
4741 It is now possible to watch array elements, struct members, and
4742 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4743 on x86 targets no longer erroneously trigger when the address is
4746 * Improvements in the native DJGPP version of GDB
4748 The distribution now includes all the scripts and auxiliary files
4749 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4750 machines ``out of the box''.
4752 The DJGPP version can now debug programs that use signals. It is
4753 possible to catch signals that happened in the debuggee, deliver
4754 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4755 would kill the program being debugged.) Programs that hook hardware
4756 interrupts (keyboard, timer, etc.) can also be debugged.
4758 It is now possible to debug DJGPP programs that redirect their
4759 standard handles or switch them to raw (as opposed to cooked) mode, or
4760 even close them. The command ``run < foo > bar'' works as expected,
4761 and ``info terminal'' reports useful information about the debuggee's
4762 terminal, including raw/cooked mode, redirection, etc.
4764 The DJGPP version now uses termios functions for console I/O, which
4765 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4768 DOS-style file names with drive letters are now fully supported by
4771 It is now possible to debug DJGPP programs that switch their working
4772 directory. It is also possible to rerun the debuggee any number of
4773 times without restarting GDB; thus, you can use the same setup,
4774 breakpoints, etc. for many debugging sessions.
4776 * New native configurations
4778 ARM GNU/Linux arm*-*-linux*
4779 PowerPC GNU/Linux powerpc-*-linux*
4783 Motorola MCore mcore-*-*
4784 x86 VxWorks i[3456]86-*-vxworks*
4785 PowerPC VxWorks powerpc-*-vxworks*
4786 TI TMS320C80 tic80-*-*
4788 * OBSOLETE configurations
4790 Altos 3068 m68*-altos-*
4791 Convex c1-*-*, c2-*-*
4793 ARM RISCix arm-*-* (as host)
4796 Configurations that have been declared obsolete will be commented out,
4797 but the code will be left in place. If there is no activity to revive
4798 these configurations before the next release of GDB, the sources will
4799 be permanently REMOVED.
4801 * Gould support removed
4803 Support for the Gould PowerNode and NP1 has been removed.
4805 * New features for SVR4
4807 On SVR4 native platforms (such as Solaris), if you attach to a process
4808 without first loading a symbol file, GDB will now attempt to locate and
4809 load symbols from the running process's executable file.
4811 * Many C++ enhancements
4813 C++ support has been greatly improved. Overload resolution now works properly
4814 in almost all cases. RTTI support is on the way.
4816 * Remote targets can connect to a sub-program
4818 A popen(3) style serial-device has been added. This device starts a
4819 sub-process (such as a stand-alone simulator) and then communicates
4820 with that. The sub-program to run is specified using the syntax
4821 ``|<program> <args>'' vis:
4823 (gdb) set remotedebug 1
4824 (gdb) target extended-remote |mn10300-elf-sim program-args
4826 * MIPS 64 remote protocol
4828 A long standing bug in the mips64 remote protocol where by GDB
4829 expected certain 32 bit registers (ex SR) to be transfered as 32
4830 instead of 64 bits has been fixed.
4832 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4833 added to provide backward compatibility with older versions of GDB.
4835 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4837 The command ``set remotebinarydownload'' command has been replaced by
4838 ``set remote X-packet''. Other commands in ``set remote'' family
4839 include ``set remote P-packet''.
4841 * Breakpoint commands accept ranges.
4843 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4844 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4845 ``tracepoint passcount'' also accepts a range of tracepoints.
4847 * ``apropos'' command added.
4849 The ``apropos'' command searches through command names and
4850 documentation strings, printing out matches, making it much easier to
4851 try to find a command that does what you are looking for.
4855 A new machine oriented interface (MI) has been added to GDB. This
4856 interface is designed for debug environments running GDB as a separate
4857 process. This is part of the long term libGDB project. See the
4858 "GDB/MI" chapter of the GDB manual for further information. It can be
4859 enabled by configuring with:
4861 .../configure --enable-gdbmi
4863 *** Changes in GDB-4.18:
4865 * New native configurations
4867 HP-UX 10.20 hppa*-*-hpux10.20
4868 HP-UX 11.x hppa*-*-hpux11.0*
4869 M68K GNU/Linux m68*-*-linux*
4873 Fujitsu FR30 fr30-*-elf*
4874 Intel StrongARM strongarm-*-*
4875 Mitsubishi D30V d30v-*-*
4877 * OBSOLETE configurations
4879 Gould PowerNode, NP1 np1-*-*, pn-*-*
4881 Configurations that have been declared obsolete will be commented out,
4882 but the code will be left in place. If there is no activity to revive
4883 these configurations before the next release of GDB, the sources will
4884 be permanently REMOVED.
4888 As a compatibility experiment, GDB's source files buildsym.h and
4889 buildsym.c have been converted to pure standard C, no longer
4890 containing any K&R compatibility code. We believe that all systems in
4891 use today either come with a standard C compiler, or have a GCC port
4892 available. If this is not true, please report the affected
4893 configuration to bug-gdb@gnu.org immediately. See the README file for
4894 information about getting a standard C compiler if you don't have one
4899 GDB now uses readline 2.2.
4901 * set extension-language
4903 You can now control the mapping between filename extensions and source
4904 languages by using the `set extension-language' command. For instance,
4905 you can ask GDB to treat .c files as C++ by saying
4906 set extension-language .c c++
4907 The command `info extensions' lists all of the recognized extensions
4908 and their associated languages.
4910 * Setting processor type for PowerPC and RS/6000
4912 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4913 you can use the `set processor' command to specify what variant of the
4914 PowerPC family you are debugging. The command
4918 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4919 following PowerPC and RS6000 variants:
4921 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4922 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4924 403GC IBM PowerPC 403GC
4925 505 Motorola PowerPC 505
4926 860 Motorola PowerPC 860 or 850
4927 601 Motorola PowerPC 601
4928 602 Motorola PowerPC 602
4929 603 Motorola/IBM PowerPC 603 or 603e
4930 604 Motorola PowerPC 604 or 604e
4931 750 Motorola/IBM PowerPC 750 or 750
4933 At the moment, this command just tells GDB what to name the
4934 special-purpose processor registers. Since almost all the affected
4935 registers are inaccessible to user-level programs, this command is
4936 only useful for remote debugging in its present form.
4940 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4941 more extensive support for HP-UX. Added features include shared
4942 library support, kernel threads and hardware watchpoints for 11.00,
4943 support for HP's ANSI C and C++ compilers, and a compatibility mode
4944 for xdb and dbx commands.
4948 HP's donation includes the new concept of catchpoints, which is a
4949 generalization of the old catch command. On HP-UX, it is now possible
4950 to catch exec, fork, and vfork, as well as library loading.
4952 This means that the existing catch command has changed; its first
4953 argument now specifies the type of catch to be set up. See the
4954 output of "help catch" for a list of catchpoint types.
4956 * Debugging across forks
4958 On HP-UX, you can choose which process to debug when a fork() happens
4963 HP has donated a curses-based terminal user interface (TUI). To get
4964 it, build with --enable-tui. Although this can be enabled for any
4965 configuration, at present it only works for native HP debugging.
4967 * GDB remote protocol additions
4969 A new protocol packet 'X' that writes binary data is now available.
4970 Default behavior is to try 'X', then drop back to 'M' if the stub
4971 fails to respond. The settable variable `remotebinarydownload'
4972 allows explicit control over the use of 'X'.
4974 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4975 full 64-bit address. The command
4977 set remoteaddresssize 32
4979 can be used to revert to the old behaviour. For existing remote stubs
4980 the change should not be noticed, as the additional address information
4983 In order to assist in debugging stubs, you may use the maintenance
4984 command `packet' to send any text string to the stub. For instance,
4986 maint packet heythere
4988 sends the packet "$heythere#<checksum>". Note that it is very easy to
4989 disrupt a debugging session by sending the wrong packet at the wrong
4992 The compare-sections command allows you to compare section data on the
4993 target to what is in the executable file without uploading or
4994 downloading, by comparing CRC checksums.
4996 * Tracing can collect general expressions
4998 You may now collect general expressions at tracepoints. This requires
4999 further additions to the target-side stub; see tracepoint.c and
5000 doc/agentexpr.texi for further details.
5002 * mask-address variable for Mips
5004 For Mips targets, you may control the zeroing of the upper 32 bits of
5005 a 64-bit address by entering `set mask-address on'. This is mainly
5006 of interest to users of embedded R4xxx and R5xxx processors.
5008 * Higher serial baud rates
5010 GDB's serial code now allows you to specify baud rates 57600, 115200,
5011 230400, and 460800 baud. (Note that your host system may not be able
5012 to achieve all of these rates.)
5016 The i960 configuration now includes an initial implementation of a
5017 builtin simulator, contributed by Jim Wilson.
5020 *** Changes in GDB-4.17:
5022 * New native configurations
5024 Alpha GNU/Linux alpha*-*-linux*
5025 Unixware 2.x i[3456]86-unixware2*
5026 Irix 6.x mips*-sgi-irix6*
5027 PowerPC GNU/Linux powerpc-*-linux*
5028 PowerPC Solaris powerpcle-*-solaris*
5029 Sparc GNU/Linux sparc-*-linux*
5030 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5034 Argonaut Risc Chip (ARC) arc-*-*
5035 Hitachi H8/300S h8300*-*-*
5036 Matsushita MN10200 w/simulator mn10200-*-*
5037 Matsushita MN10300 w/simulator mn10300-*-*
5038 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5039 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5040 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5041 Mitsubishi D10V w/simulator d10v-*-*
5042 Mitsubishi M32R/D w/simulator m32r-*-elf*
5043 Tsqware Sparclet sparclet-*-*
5044 NEC V850 w/simulator v850-*-*
5046 * New debugging protocols
5048 ARM with RDI protocol arm*-*-*
5049 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5050 DDB and LSI variants of PMON protocol mips*-*-*
5051 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5052 PowerPC with SDS protocol powerpc{,le}-*-eabi
5053 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5057 All configurations can now understand and use the DWARF 2 debugging
5058 format. The choice is automatic, if the symbol file contains DWARF 2
5063 GDB now includes basic Java language support. This support is
5064 only useful with Java compilers that produce native machine code.
5066 * solib-absolute-prefix and solib-search-path
5068 For SunOS and SVR4 shared libraries, you may now set the prefix for
5069 loading absolute shared library symbol files, and the search path for
5070 locating non-absolute shared library symbol files.
5072 * Live range splitting
5074 GDB can now effectively debug code for which GCC has performed live
5075 range splitting as part of its optimization. See gdb/doc/LRS for
5076 more details on the expected format of the stabs information.
5080 GDB's support for the GNU Hurd, including thread debugging, has been
5081 updated to work with current versions of the Hurd.
5085 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5086 instruction set. ARM GDB automatically detects when Thumb
5087 instructions are in use, and adjusts disassembly and backtracing
5092 GDB's MIPS target configurations now handle the MIP16 16-bit
5097 GDB now includes support for overlays; if an executable has been
5098 linked such that multiple sections are based at the same address, GDB
5099 will decide which section to use for symbolic info. You can choose to
5100 control the decision manually, using overlay commands, or implement
5101 additional target-side support and use "overlay load-target" to bring
5102 in the overlay mapping. Do "help overlay" for more detail.
5106 The command "info symbol <address>" displays information about
5107 the symbol at the specified address.
5111 The standard remote protocol now includes an extension that allows
5112 asynchronous collection and display of trace data. This requires
5113 extensive support in the target-side debugging stub. Tracing mode
5114 includes a new interaction mode in GDB and new commands: see the
5115 file tracepoint.c for more details.
5119 Configurations for embedded MIPS now include a simulator contributed
5120 by Cygnus Solutions. The simulator supports the instruction sets
5121 of most MIPS variants.
5125 Sparc configurations may now include the ERC32 simulator contributed
5126 by the European Space Agency. The simulator is not built into
5127 Sparc targets by default; configure with --enable-sim to include it.
5131 For target configurations that may include multiple variants of a
5132 basic architecture (such as MIPS and SH), you may now set the
5133 architecture explicitly. "set arch" sets, "info arch" lists
5134 the possible architectures.
5136 *** Changes in GDB-4.16:
5138 * New native configurations
5140 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5141 M68K NetBSD m68k-*-netbsd*
5142 PowerPC AIX 4.x powerpc-*-aix*
5143 PowerPC MacOS powerpc-*-macos*
5144 PowerPC Windows NT powerpcle-*-cygwin32
5145 RS/6000 AIX 4.x rs6000-*-aix4*
5149 ARM with RDP protocol arm-*-*
5150 I960 with MON960 i960-*-coff
5151 MIPS VxWorks mips*-*-vxworks*
5152 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5153 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5155 Matra Sparclet sparclet-*-*
5159 The powerpc-eabi configuration now includes the PSIM simulator,
5160 contributed by Andrew Cagney, with assistance from Mike Meissner.
5161 PSIM is a very elaborate model of the PowerPC, including not only
5162 basic instruction set execution, but also details of execution unit
5163 performance and I/O hardware. See sim/ppc/README for more details.
5167 GDB now works with Solaris 2.5.
5169 * Windows 95/NT native
5171 GDB will now work as a native debugger on Windows 95 and Windows NT.
5172 To build it from source, you must use the "gnu-win32" environment,
5173 which uses a DLL to emulate enough of Unix to run the GNU tools.
5174 Further information, binaries, and sources are available at
5175 ftp.cygnus.com, under pub/gnu-win32.
5177 * dont-repeat command
5179 If a user-defined command includes the command `dont-repeat', then the
5180 command will not be repeated if the user just types return. This is
5181 useful if the command is time-consuming to run, so that accidental
5182 extra keystrokes don't run the same command many times.
5184 * Send break instead of ^C
5186 The standard remote protocol now includes an option to send a break
5187 rather than a ^C to the target in order to interrupt it. By default,
5188 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5190 * Remote protocol timeout
5192 The standard remote protocol includes a new variable `remotetimeout'
5193 that allows you to set the number of seconds before GDB gives up trying
5194 to read from the target. The default value is 2.
5196 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5198 By default GDB will automatically keep track of objects as they are
5199 loaded and unloaded by the dynamic linker. By using the command `set
5200 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5201 when shared library events occur, thus allowing you to set breakpoints
5202 in shared libraries which are explicitly loaded by the inferior.
5204 Note this feature does not work on hpux8. On hpux9 you must link
5205 /usr/lib/end.o into your program. This feature should work
5206 automatically on hpux10.
5208 * Irix 5.x hardware watchpoint support
5210 Irix 5 configurations now support the use of hardware watchpoints.
5212 * Mips protocol "SYN garbage limit"
5214 When debugging a Mips target using the `target mips' protocol, you
5215 may set the number of characters that GDB will ignore by setting
5216 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5217 every character. The default value is 1050.
5219 * Recording and replaying remote debug sessions
5221 If you set `remotelogfile' to the name of a file, gdb will write to it
5222 a recording of a remote debug session. This recording may then be
5223 replayed back to gdb using "gdbreplay". See gdbserver/README for
5224 details. This is useful when you have a problem with GDB while doing
5225 remote debugging; you can make a recording of the session and send it
5226 to someone else, who can then recreate the problem.
5228 * Speedups for remote debugging
5230 GDB includes speedups for downloading and stepping MIPS systems using
5231 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5232 and more efficient S-record downloading.
5234 * Memory use reductions and statistics collection
5236 GDB now uses less memory and reports statistics about memory usage.
5237 Try the `maint print statistics' command, for example.
5239 *** Changes in GDB-4.15:
5241 * Psymtabs for XCOFF
5243 The symbol reader for AIX GDB now uses partial symbol tables. This
5244 can greatly improve startup time, especially for large executables.
5246 * Remote targets use caching
5248 Remote targets now use a data cache to speed up communication with the
5249 remote side. The data cache could lead to incorrect results because
5250 it doesn't know about volatile variables, thus making it impossible to
5251 debug targets which use memory mapped I/O devices. `set remotecache
5252 off' turns the the data cache off.
5254 * Remote targets may have threads
5256 The standard remote protocol now includes support for multiple threads
5257 in the target system, using new protocol commands 'H' and 'T'. See
5258 gdb/remote.c for details.
5262 If GDB is configured with `--enable-netrom', then it will include
5263 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5264 acts as though it is a bank of ROM on the target board, but you can
5265 write into it over the network. GDB's support consists only of
5266 support for fast loading into the emulated ROM; to debug, you must use
5267 another protocol, such as standard remote protocol. The usual
5268 sequence is something like
5270 target nrom <netrom-hostname>
5272 target remote <netrom-hostname>:1235
5276 GDB now includes support for the Apple Macintosh, as a host only. It
5277 may be run as either an MPW tool or as a standalone application, and
5278 it can debug through the serial port. All the usual GDB commands are
5279 available, but to the target command, you must supply "serial" as the
5280 device type instead of "/dev/ttyXX". See mpw-README in the main
5281 directory for more information on how to build. The MPW configuration
5282 scripts */mpw-config.in support only a few targets, and only the
5283 mips-idt-ecoff target has been tested.
5287 GDB configuration now uses autoconf. This is not user-visible,
5288 but does simplify configuration and building.
5292 GDB now supports hpux10.
5294 *** Changes in GDB-4.14:
5296 * New native configurations
5298 x86 FreeBSD i[345]86-*-freebsd
5299 x86 NetBSD i[345]86-*-netbsd
5300 NS32k NetBSD ns32k-*-netbsd
5301 Sparc NetBSD sparc-*-netbsd
5305 A29K VxWorks a29k-*-vxworks
5306 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5307 CPU32 EST-300 emulator m68*-*-est*
5308 PowerPC ELF powerpc-*-elf
5311 * Alpha OSF/1 support for procfs
5313 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5314 possible to attach to running processes. As the mounting of the /proc
5315 filesystem is optional on the Alpha, GDB automatically determines
5316 the availability of /proc during startup. This can lead to problems
5317 if /proc is unmounted after GDB has been started.
5319 * Arguments to user-defined commands
5321 User commands may accept up to 10 arguments separated by whitespace.
5322 Arguments are accessed within the user command via $arg0..$arg9. A
5325 print $arg0 + $arg1 + $arg2
5327 To execute the command use:
5330 Defines the command "adder" which prints the sum of its three arguments.
5331 Note the arguments are text substitutions, so they may reference variables,
5332 use complex expressions, or even perform inferior function calls.
5334 * New `if' and `while' commands
5336 This makes it possible to write more sophisticated user-defined
5337 commands. Both commands take a single argument, which is the
5338 expression to evaluate, and must be followed by the commands to
5339 execute, one per line, if the expression is nonzero, the list being
5340 terminated by the word `end'. The `if' command list may include an
5341 `else' word, which causes the following commands to be executed only
5342 if the expression is zero.
5344 * Fortran source language mode
5346 GDB now includes partial support for Fortran 77. It will recognize
5347 Fortran programs and can evaluate a subset of Fortran expressions, but
5348 variables and functions may not be handled correctly. GDB will work
5349 with G77, but does not yet know much about symbols emitted by other
5352 * Better HPUX support
5354 Most debugging facilities now work on dynamic executables for HPPAs
5355 running hpux9 or later. You can attach to running dynamically linked
5356 processes, but by default the dynamic libraries will be read-only, so
5357 for instance you won't be able to put breakpoints in them. To change
5358 that behavior do the following before running the program:
5364 This will cause the libraries to be mapped private and read-write.
5365 To revert to the normal behavior, do this:
5371 You cannot set breakpoints or examine data in the library until after
5372 the library is loaded if the function/data symbols do not have
5375 GDB can now also read debug symbols produced by the HP C compiler on
5376 HPPAs (sorry, no C++, Fortran or 68k support).
5378 * Target byte order now dynamically selectable
5380 You can choose which byte order to use with a target system, via the
5381 commands "set endian big" and "set endian little", and you can see the
5382 current setting by using "show endian". You can also give the command
5383 "set endian auto", in which case GDB will use the byte order
5384 associated with the executable. Currently, only embedded MIPS
5385 configurations support dynamic selection of target byte order.
5387 * New DOS host serial code
5389 This version uses DPMI interrupts to handle buffered I/O, so you
5390 no longer need to run asynctsr when debugging boards connected to
5393 *** Changes in GDB-4.13:
5395 * New "complete" command
5397 This lists all the possible completions for the rest of the line, if it
5398 were to be given as a command itself. This is intended for use by emacs.
5400 * Trailing space optional in prompt
5402 "set prompt" no longer adds a space for you after the prompt you set. This
5403 allows you to set a prompt which ends in a space or one that does not.
5405 * Breakpoint hit counts
5407 "info break" now displays a count of the number of times the breakpoint
5408 has been hit. This is especially useful in conjunction with "ignore"; you
5409 can ignore a large number of breakpoint hits, look at the breakpoint info
5410 to see how many times the breakpoint was hit, then run again, ignoring one
5411 less than that number, and this will get you quickly to the last hit of
5414 * Ability to stop printing at NULL character
5416 "set print null-stop" will cause GDB to stop printing the characters of
5417 an array when the first NULL is encountered. This is useful when large
5418 arrays actually contain only short strings.
5420 * Shared library breakpoints
5422 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5423 breakpoints in shared libraries before the executable is run.
5425 * Hardware watchpoints
5427 There is a new hardware breakpoint for the watch command for sparclite
5428 targets. See gdb/sparclite/hw_breakpoint.note.
5430 Hardware watchpoints are also now supported under GNU/Linux.
5434 Annotations have been added. These are for use with graphical interfaces,
5435 and are still experimental. Currently only gdba.el uses these.
5437 * Improved Irix 5 support
5439 GDB now works properly with Irix 5.2.
5441 * Improved HPPA support
5443 GDB now works properly with the latest GCC and GAS.
5445 * New native configurations
5447 Sequent PTX4 i[34]86-sequent-ptx4
5448 HPPA running OSF/1 hppa*-*-osf*
5449 Atari TT running SVR4 m68*-*-sysv4*
5450 RS/6000 LynxOS rs6000-*-lynxos*
5454 OS/9000 i[34]86-*-os9k
5455 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5458 * Hitachi SH7000 and E7000-PC ICE support
5460 There is now support for communicating with the Hitachi E7000-PC ICE.
5461 This is available automatically when GDB is configured for the SH.
5465 As usual, a variety of small fixes and improvements, both generic
5466 and configuration-specific. See the ChangeLog for more detail.
5468 *** Changes in GDB-4.12:
5470 * Irix 5 is now supported
5474 GDB-4.12 on the HPPA has a number of changes which make it unable
5475 to debug the output from the currently released versions of GCC and
5476 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5477 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5478 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5481 *** Changes in GDB-4.11:
5483 * User visible changes:
5487 The "set remotedebug" option is now consistent between the mips remote
5488 target, remote targets using the gdb-specific protocol, UDI (AMD's
5489 debug protocol for the 29k) and the 88k bug monitor. It is now an
5490 integer specifying a debug level (normally 0 or 1, but 2 means more
5491 debugging info for the mips target).
5493 * DEC Alpha native support
5495 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5496 debug info, but GDB works fairly well with the DEC compiler and should
5497 work with a future GCC release. See the README file for a few
5498 Alpha-specific notes.
5500 * Preliminary thread implementation
5502 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5504 * LynxOS native and target support for 386
5506 This release has been hosted on LynxOS 2.2, and also can be configured
5507 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5510 * Improvements in C++ mangling/demangling.
5512 This release has much better g++ debugging, specifically in name
5513 mangling/demangling, virtual function calls, print virtual table,
5514 call methods, ...etc.
5516 *** Changes in GDB-4.10:
5518 * User visible changes:
5520 Remote debugging using the GDB-specific (`target remote') protocol now
5521 supports the `load' command. This is only useful if you have some
5522 other way of getting the stub to the target system, and you can put it
5523 somewhere in memory where it won't get clobbered by the download.
5525 Filename completion now works.
5527 When run under emacs mode, the "info line" command now causes the
5528 arrow to point to the line specified. Also, "info line" prints
5529 addresses in symbolic form (as well as hex).
5531 All vxworks based targets now support a user settable option, called
5532 vxworks-timeout. This option represents the number of seconds gdb
5533 should wait for responses to rpc's. You might want to use this if
5534 your vxworks target is, perhaps, a slow software simulator or happens
5535 to be on the far side of a thin network line.
5539 This release contains support for using a DEC alpha as a GDB host for
5540 cross debugging. Native alpha debugging is not supported yet.
5543 *** Changes in GDB-4.9:
5547 This is the first GDB release which is accompanied by a matching testsuite.
5548 The testsuite requires installation of dejagnu, which should be available
5549 via ftp from most sites that carry GNU software.
5553 'Cfront' style demangling has had its name changed to 'ARM' style, to
5554 emphasize that it was written from the specifications in the C++ Annotated
5555 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5556 disclaimers, it still generated too much confusion with users attempting to
5557 use gdb with AT&T cfront.
5561 GDB now uses a standard remote interface to a simulator library.
5562 So far, the library contains simulators for the Zilog Z8001/2, the
5563 Hitachi H8/300, H8/500 and Super-H.
5565 * New targets supported
5567 H8/300 simulator h8300-hitachi-hms or h8300hms
5568 H8/500 simulator h8500-hitachi-hms or h8500hms
5569 SH simulator sh-hitachi-hms or sh
5570 Z8000 simulator z8k-zilog-none or z8ksim
5571 IDT MIPS board over serial line mips-idt-ecoff
5573 Cross-debugging to GO32 targets is supported. It requires a custom
5574 version of the i386-stub.c module which is integrated with the
5575 GO32 memory extender.
5577 * New remote protocols
5579 MIPS remote debugging protocol.
5581 * New source languages supported
5583 This version includes preliminary support for Chill, a Pascal like language
5584 used by telecommunications companies. Chill support is also being integrated
5585 into the GNU compiler, but we don't know when it will be publically available.
5588 *** Changes in GDB-4.8:
5590 * HP Precision Architecture supported
5592 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5593 version of this support was available as a set of patches from the
5594 University of Utah. GDB does not support debugging of programs
5595 compiled with the HP compiler, because HP will not document their file
5596 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5597 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5599 Many problems in the preliminary version have been fixed.
5601 * Faster and better demangling
5603 We have improved template demangling and fixed numerous bugs in the GNU style
5604 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5605 character types (wchar_t) are now supported. Demangling of each symbol is now
5606 only done once, and is cached when the symbol table for a file is read in.
5607 This results in a small increase in memory usage for C programs, a moderate
5608 increase in memory usage for C++ programs, and a fantastic speedup in
5611 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5612 from the specifications in the Annotated Reference Manual, which AT&T's
5613 compiler does not actually implement.
5615 * G++ multiple inheritance compiler problem
5617 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5618 inheritance lattices was reworked to properly discover ambiguities. We
5619 recently found an example which causes this new algorithm to fail in a
5620 very subtle way, producing bad debug information for those classes.
5621 The file 'gcc.patch' (in this directory) can be applied to gcc to
5622 circumvent the problem. A future GCC release will contain a complete
5625 The previous G++ debug info problem (mentioned below for the gdb-4.7
5626 release) is fixed in gcc version 2.3.2.
5628 * Improved configure script
5630 The `configure' script will now attempt to guess your system type if
5631 you don't supply a host system type. The old scheme of supplying a
5632 host system triplet is preferable over using this. All the magic is
5633 done in the new `config.guess' script. Examine it for details.
5635 We have also brought our configure script much more in line with the FSF's
5636 version. It now supports the --with-xxx options. In particular,
5637 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5638 The resulting GDB will not be able to read arbitrary object file formats --
5639 only the format ``expected'' to be used on the configured target system.
5640 We hope to make this the default in a future release.
5642 * Documentation improvements
5644 There's new internal documentation on how to modify GDB, and how to
5645 produce clean changes to the code. We implore people to read it
5646 before submitting changes.
5648 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5649 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5650 `info' files are also provided. To build `info' files from scratch,
5651 you will need the latest `makeinfo' release, which will be available in
5652 a future texinfo-X.Y release.
5654 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5655 We're not sure exactly which versions have this problem, but it has
5656 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5657 or better. If that isn't possible, there is a patch in
5658 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5659 around this problem.
5663 GDB now supports array constants that can be used in expressions typed in by
5664 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5665 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5668 The new directory `gdb/sparclite' contains a program that demonstrates
5669 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5671 * New native hosts supported
5673 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5674 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5676 * New targets supported
5678 AMD 29k family via UDI a29k-amd-udi or udi29k
5680 * New file formats supported
5682 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5683 HPUX core files, and SCO 3.2v2 core files.
5687 Attaching to processes now works again; thanks for the many bug reports.
5689 We have also stomped on a bunch of core dumps caused by
5690 printf_filtered("%s") problems.
5692 We eliminated a copyright problem on the rpc and ptrace header files
5693 for VxWorks, which was discovered at the last minute during the 4.7
5694 release. You should now be able to build a VxWorks GDB.
5696 You can now interrupt gdb while an attached process is running. This
5697 will cause the attached process to stop, and give control back to GDB.
5699 We fixed problems caused by using too many file descriptors
5700 for reading symbols from object files and libraries. This was
5701 especially a problem for programs that used many (~100) shared
5704 The `step' command now only enters a subroutine if there is line number
5705 information for the subroutine. Otherwise it acts like the `next'
5706 command. Previously, `step' would enter subroutines if there was
5707 any debugging information about the routine. This avoids problems
5708 when using `cc -g1' on MIPS machines.
5710 * Internal improvements
5712 GDB's internal interfaces have been improved to make it easier to support
5713 debugging of multiple languages in the future.
5715 GDB now uses a common structure for symbol information internally.
5716 Minimal symbols (derived from linkage symbols in object files), partial
5717 symbols (from a quick scan of debug information), and full symbols
5718 contain a common subset of information, making it easier to write
5719 shared code that handles any of them.
5721 * New command line options
5723 We now accept --silent as an alias for --quiet.
5727 The memory-mapped-malloc library is now licensed under the GNU Library
5728 General Public License.
5730 *** Changes in GDB-4.7:
5732 * Host/native/target split
5734 GDB has had some major internal surgery to untangle the support for
5735 hosts and remote targets. Now, when you configure GDB for a remote
5736 target, it will no longer load in all of the support for debugging
5737 local programs on the host. When fully completed and tested, this will
5738 ensure that arbitrary host/target combinations are possible.
5740 The primary conceptual shift is to separate the non-portable code in
5741 GDB into three categories. Host specific code is required any time GDB
5742 is compiled on that host, regardless of the target. Target specific
5743 code relates to the peculiarities of the target, but can be compiled on
5744 any host. Native specific code is everything else: it can only be
5745 built when the host and target are the same system. Child process
5746 handling and core file support are two common `native' examples.
5748 GDB's use of /proc for controlling Unix child processes is now cleaner.
5749 It has been split out into a single module under the `target_ops' vector,
5750 plus two native-dependent functions for each system that uses /proc.
5752 * New hosts supported
5754 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5755 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5756 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5758 * New targets supported
5760 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5761 68030 and CPU32 m68030-*-*, m68332-*-*
5763 * New native hosts supported
5765 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5766 (386bsd is not well tested yet)
5767 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5769 * New file formats supported
5771 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5772 supports reading of `a.out.adobe' object files, which are an a.out
5773 format extended with minimal information about multiple sections.
5777 `show copying' is the same as the old `info copying'.
5778 `show warranty' is the same as `info warrantee'.
5779 These were renamed for consistency. The old commands continue to work.
5781 `info handle' is a new alias for `info signals'.
5783 You can now define pre-command hooks, which attach arbitrary command
5784 scripts to any command. The commands in the hook will be executed
5785 prior to the user's command. You can also create a hook which will be
5786 executed whenever the program stops. See gdb.texinfo.
5790 We now deal with Cfront style name mangling, and can even extract type
5791 info from mangled symbols. GDB can automatically figure out which
5792 symbol mangling style your C++ compiler uses.
5794 Calling of methods and virtual functions has been improved as well.
5798 The crash that occured when debugging Sun Ansi-C compiled binaries is
5799 fixed. This was due to mishandling of the extra N_SO stabs output
5802 We also finally got Ultrix 4.2 running in house, and fixed core file
5803 support, with help from a dozen people on the net.
5805 John M. Farrell discovered that the reason that single-stepping was so
5806 slow on all of the Mips based platforms (primarily SGI and DEC) was
5807 that we were trying to demangle and lookup a symbol used for internal
5808 purposes on every instruction that was being stepped through. Changing
5809 the name of that symbol so that it couldn't be mistaken for a C++
5810 mangled symbol sped things up a great deal.
5812 Rich Pixley sped up symbol lookups in general by getting much smarter
5813 about when C++ symbol mangling is necessary. This should make symbol
5814 completion (TAB on the command line) much faster. It's not as fast as
5815 we'd like, but it's significantly faster than gdb-4.6.
5819 A new user controllable variable 'call_scratch_address' can
5820 specify the location of a scratch area to be used when GDB
5821 calls a function in the target. This is necessary because the
5822 usual method of putting the scratch area on the stack does not work
5823 in systems that have separate instruction and data spaces.
5825 We integrated changes to support the 29k UDI (Universal Debugger
5826 Interface), but discovered at the last minute that we didn't have all
5827 of the appropriate copyright paperwork. We are working with AMD to
5828 resolve this, and hope to have it available soon.
5832 We have sped up the remote serial line protocol, especially for targets
5833 with lots of registers. It now supports a new `expedited status' ('T')
5834 message which can be used in place of the existing 'S' status message.
5835 This allows the remote stub to send only the registers that GDB
5836 needs to make a quick decision about single-stepping or conditional
5837 breakpoints, eliminating the need to fetch the entire register set for
5838 each instruction being stepped through.
5840 The GDB remote serial protocol now implements a write-through cache for
5841 registers, only re-reading the registers if the target has run.
5843 There is also a new remote serial stub for SPARC processors. You can
5844 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5845 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5846 processor with a serial port.
5850 Configure.in files have become much easier to read and modify. A new
5851 `table driven' format makes it more obvious what configurations are
5852 supported, and what files each one uses.
5856 There is a new opcodes library which will eventually contain all of the
5857 disassembly routines and opcode tables. At present, it only contains
5858 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5859 disassembler (binutils/objdump) to share these routines.
5861 The libiberty library is now copylefted under the GNU Library General
5862 Public License. This allows more liberal use, and was done so libg++
5863 can use it. This makes no difference to GDB, since the Library License
5864 grants all the rights from the General Public License.
5868 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5869 reference to the stabs symbol info used by the debugger. It is (as far
5870 as we know) the only published document on this fascinating topic. We
5871 encourage you to read it, compare it to the stabs information on your
5872 system, and send improvements on the document in general (to
5873 bug-gdb@prep.ai.mit.edu).
5875 And, of course, many bugs have been fixed.
5878 *** Changes in GDB-4.6:
5880 * Better support for C++ function names
5882 GDB now accepts as input the "demangled form" of C++ overloaded function
5883 names and member function names, and can do command completion on such names
5884 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5885 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5886 Make use of command completion, it is your friend.
5888 GDB also now accepts a variety of C++ mangled symbol formats. They are
5889 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5890 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5891 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5892 for the list of formats.
5894 * G++ symbol mangling problem
5896 Recent versions of gcc have a bug in how they emit debugging information for
5897 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5898 directory) can be applied to gcc to fix the problem. Alternatively, if you
5899 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5900 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5901 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5904 * New 'maintenance' command
5906 All of the commands related to hacking GDB internals have been moved out of
5907 the main command set, and now live behind the 'maintenance' command. This
5908 can also be abbreviated as 'mt'. The following changes were made:
5910 dump-me -> maintenance dump-me
5911 info all-breakpoints -> maintenance info breakpoints
5912 printmsyms -> maintenance print msyms
5913 printobjfiles -> maintenance print objfiles
5914 printpsyms -> maintenance print psymbols
5915 printsyms -> maintenance print symbols
5917 The following commands are new:
5919 maintenance demangle Call internal GDB demangler routine to
5920 demangle a C++ link name and prints the result.
5921 maintenance print type Print a type chain for a given symbol
5923 * Change to .gdbinit file processing
5925 We now read the $HOME/.gdbinit file before processing the argv arguments
5926 (e.g. reading symbol files or core files). This allows global parameters to
5927 be set, which will apply during the symbol reading. The ./.gdbinit is still
5928 read after argv processing.
5930 * New hosts supported
5932 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5934 GNU/Linux support i386-unknown-linux or linux
5936 We are also including code to support the HP/PA running BSD and HPUX. This
5937 is almost guaranteed not to work, as we didn't have time to test or build it
5938 for this release. We are including it so that the more adventurous (or
5939 masochistic) of you can play with it. We also had major problems with the
5940 fact that the compiler that we got from HP doesn't support the -g option.
5943 * New targets supported
5945 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5947 * More smarts about finding #include files
5949 GDB now remembers the compilation directory for all include files, and for
5950 all files from which C is generated (like yacc and lex sources). This
5951 greatly improves GDB's ability to find yacc/lex sources, and include files,
5952 especially if you are debugging your program from a directory different from
5953 the one that contains your sources.
5955 We also fixed a bug which caused difficulty with listing and setting
5956 breakpoints in include files which contain C code. (In the past, you had to
5957 try twice in order to list an include file that you hadn't looked at before.)
5959 * Interesting infernals change
5961 GDB now deals with arbitrary numbers of sections, where the symbols for each
5962 section must be relocated relative to that section's landing place in the
5963 target's address space. This work was needed to support ELF with embedded
5964 stabs used by Solaris-2.0.
5966 * Bug fixes (of course!)
5968 There have been loads of fixes for the following things:
5969 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5970 i960, stabs, DOS(GO32), procfs, etc...
5972 See the ChangeLog for details.
5974 *** Changes in GDB-4.5:
5976 * New machines supported (host and target)
5978 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5980 SGI Irix-4.x mips-sgi-irix4 or iris4
5982 * New malloc package
5984 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5985 Mmalloc is capable of handling mutiple heaps of memory. It is also
5986 capable of saving a heap to a file, and then mapping it back in later.
5987 This can be used to greatly speedup the startup of GDB by using a
5988 pre-parsed symbol table which lives in a mmalloc managed heap. For
5989 more details, please read mmalloc/mmalloc.texi.
5993 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5994 'help info proc' for details.
5996 * MIPS ecoff symbol table format
5998 The code that reads MIPS symbol table format is now supported on all hosts.
5999 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6002 * File name changes for MS-DOS
6004 Many files in the config directories have been renamed to make it easier to
6005 support GDB on MS-DOSe systems (which have very restrictive file name
6006 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6007 environment) is close to working but has some remaining problems. Note
6008 that debugging of DOS programs is not supported, due to limitations
6009 in the ``operating system'', but it can be used to host cross-debugging.
6011 * Cross byte order fixes
6013 Many fixes have been made to support cross debugging of Sparc and MIPS
6014 targets from hosts whose byte order differs.
6016 * New -mapped and -readnow options
6018 If memory-mapped files are available on your system through the 'mmap'
6019 system call, you can use the -mapped option on the `file' or
6020 `symbol-file' commands to cause GDB to write the symbols from your
6021 program into a reusable file. If the program you are debugging is
6022 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6023 Future GDB debugging sessions will notice the presence of this file,
6024 and will quickly map in symbol information from it, rather than reading
6025 the symbol table from the executable program. Using the '-mapped'
6026 option in a GDB `file' or `symbol-file' command has the same effect as
6027 starting GDB with the '-mapped' command-line option.
6029 You can cause GDB to read the entire symbol table immediately by using
6030 the '-readnow' option with any of the commands that load symbol table
6031 information (or on the GDB command line). This makes the command
6032 slower, but makes future operations faster.
6034 The -mapped and -readnow options are typically combined in order to
6035 build a `fred.syms' file that contains complete symbol information.
6036 A simple GDB invocation to do nothing but build a `.syms' file for future
6039 gdb -batch -nx -mapped -readnow programname
6041 The `.syms' file is specific to the host machine on which GDB is run.
6042 It holds an exact image of GDB's internal symbol table. It cannot be
6043 shared across multiple host platforms.
6045 * longjmp() handling
6047 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6048 siglongjmp() without losing control. This feature has not yet been ported to
6049 all systems. It currently works on many 386 platforms, all MIPS-based
6050 platforms (SGI, DECstation, etc), and Sun3/4.
6054 Preliminary work has been put in to support the new Solaris OS from Sun. At
6055 this time, it can control and debug processes, but it is not capable of
6060 As always, many many bug fixes. The major areas were with g++, and mipsread.
6061 People using the MIPS-based platforms should experience fewer mysterious
6062 crashes and trashed symbol tables.
6064 *** Changes in GDB-4.4:
6066 * New machines supported (host and target)
6068 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6070 BSD Reno on Vax vax-dec-bsd
6071 Ultrix on Vax vax-dec-ultrix
6073 * New machines supported (target)
6075 AMD 29000 embedded, using EBMON a29k-none-none
6079 GDB continues to improve its handling of C++. `References' work better.
6080 The demangler has also been improved, and now deals with symbols mangled as
6081 per the Annotated C++ Reference Guide.
6083 GDB also now handles `stabs' symbol information embedded in MIPS
6084 `ecoff' symbol tables. Since the ecoff format was not easily
6085 extensible to handle new languages such as C++, this appeared to be a
6086 good way to put C++ debugging info into MIPS binaries. This option
6087 will be supported in the GNU C compiler, version 2, when it is
6090 * New features for SVR4
6092 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6093 shared libraries. Debugging dynamically linked programs should present
6094 only minor differences from debugging statically linked programs.
6096 The `info proc' command will print out information about any process
6097 on an SVR4 system (including the one you are debugging). At the moment,
6098 it prints the address mappings of the process.
6100 If you bring up GDB on another SVR4 system, please send mail to
6101 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6103 * Better dynamic linking support in SunOS
6105 Reading symbols from shared libraries which contain debugging symbols
6106 now works properly. However, there remain issues such as automatic
6107 skipping of `transfer vector' code during function calls, which
6108 make it harder to debug code in a shared library, than to debug the
6109 same code linked statically.
6113 GDB is now using the latest `getopt' routines from the FSF. This
6114 version accepts the -- prefix for options with long names. GDB will
6115 continue to accept the old forms (-option and +option) as well.
6116 Various single letter abbreviations for options have been explicity
6117 added to the option table so that they won't get overshadowed in the
6118 future by other options that begin with the same letter.
6122 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6123 Many assorted bugs have been handled. Many more remain to be handled.
6124 See the various ChangeLog files (primarily in gdb and bfd) for details.
6127 *** Changes in GDB-4.3:
6129 * New machines supported (host and target)
6131 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6132 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6133 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6135 * Almost SCO Unix support
6137 We had hoped to support:
6138 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6139 (except for core file support), but we discovered very late in the release
6140 that it has problems with process groups that render gdb unusable. Sorry
6141 about that. I encourage people to fix it and post the fixes.
6143 * Preliminary ELF and DWARF support
6145 GDB can read ELF object files on System V Release 4, and can handle
6146 debugging records for C, in DWARF format, in ELF files. This support
6147 is preliminary. If you bring up GDB on another SVR4 system, please
6148 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6153 GDB now uses the latest `readline' library. One user-visible change
6154 is that two tabs will list possible command completions, which previously
6155 required typing M-? (meta-question mark, or ESC ?).
6159 The `stepi' bug that many of you noticed has been squashed.
6160 Many bugs in C++ have been handled. Many more remain to be handled.
6161 See the various ChangeLog files (primarily in gdb and bfd) for details.
6163 * State of the MIPS world (in case you wondered):
6165 GDB can understand the symbol tables emitted by the compilers
6166 supplied by most vendors of MIPS-based machines, including DEC. These
6167 symbol tables are in a format that essentially nobody else uses.
6169 Some versions of gcc come with an assembler post-processor called
6170 mips-tfile. This program is required if you want to do source-level
6171 debugging of gcc-compiled programs. I believe FSF does not ship
6172 mips-tfile with gcc version 1, but it will eventually come with gcc
6175 Debugging of g++ output remains a problem. g++ version 1.xx does not
6176 really support it at all. (If you're lucky, you should be able to get
6177 line numbers and stack traces to work, but no parameters or local
6178 variables.) With some work it should be possible to improve the
6181 When gcc version 2 is released, you will have somewhat better luck.
6182 However, even then you will get confusing results for inheritance and
6185 We will eventually provide full debugging of g++ output on
6186 DECstations. This will probably involve some kind of stabs-in-ecoff
6187 encapulation, but the details have not been worked out yet.
6190 *** Changes in GDB-4.2:
6192 * Improved configuration
6194 Only one copy of `configure' exists now, and it is not self-modifying.
6195 Porting BFD is simpler.
6199 The `step' and `next' commands now only stop at the first instruction
6200 of a source line. This prevents the multiple stops that used to occur
6201 in switch statements, for-loops, etc. `Step' continues to stop if a
6202 function that has debugging information is called within the line.
6206 Lots of small bugs fixed. More remain.
6208 * New host supported (not target)
6210 Intel 386 PC clone running Mach i386-none-mach
6213 *** Changes in GDB-4.1:
6215 * Multiple source language support
6217 GDB now has internal scaffolding to handle several source languages.
6218 It determines the type of each source file from its filename extension,
6219 and will switch expression parsing and number formatting to match the
6220 language of the function in the currently selected stack frame.
6221 You can also specifically set the language to be used, with
6222 `set language c' or `set language modula-2'.
6226 GDB now has preliminary support for the GNU Modula-2 compiler,
6227 currently under development at the State University of New York at
6228 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6229 continue through the fall of 1991 and into 1992.
6231 Other Modula-2 compilers are currently not supported, and attempting to
6232 debug programs compiled with them will likely result in an error as the
6233 symbol table is read. Feel free to work on it, though!
6235 There are hooks in GDB for strict type checking and range checking,
6236 in the `Modula-2 philosophy', but they do not currently work.
6240 GDB can now write to executable and core files (e.g. patch
6241 a variable's value). You must turn this switch on, specify
6242 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6243 by assigning a new value to a variable. Modifications take
6246 * Automatic SunOS shared library reading
6248 When you run your program, GDB automatically determines where its
6249 shared libraries (if any) have been loaded, and reads their symbols.
6250 The `share' command is no longer needed. This also works when
6251 examining core files.
6255 You can specify the number of lines that the `list' command shows.
6258 * New machines supported (host and target)
6260 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6261 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6262 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6264 * New hosts supported (not targets)
6266 IBM RT/PC: romp-ibm-aix or rtpc
6268 * New targets supported (not hosts)
6270 AMD 29000 embedded with COFF a29k-none-coff
6271 AMD 29000 embedded with a.out a29k-none-aout
6272 Ultracomputer remote kernel debug a29k-nyu-kern
6274 * New remote interfaces
6280 *** Changes in GDB-4.0:
6284 Wide output is wrapped at good places to make the output more readable.
6286 Gdb now supports cross-debugging from a host machine of one type to a
6287 target machine of another type. Communication with the target system
6288 is over serial lines. The ``target'' command handles connecting to the
6289 remote system; the ``load'' command will download a program into the
6290 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6291 also supports debugging of realtime processes running under VxWorks,
6292 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6293 stub on the target system.
6295 New CPUs supported include the AMD 29000 and Intel 960.
6297 GDB now reads object files and symbol tables via a ``binary file''
6298 library, which allows a single copy of GDB to debug programs of multiple
6299 object file types such as a.out and coff.
6301 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6302 refcard.dvi and refcard.ps are available to format it).
6305 * Control-Variable user interface simplified
6307 All variables that control the operation of the debugger can be set
6308 by the ``set'' command, and displayed by the ``show'' command.
6310 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6311 ``Show prompt'' produces the response:
6312 Gdb's prompt is new-gdb=>.
6314 What follows are the NEW set commands. The command ``help set'' will
6315 print a complete list of old and new set commands. ``help set FOO''
6316 will give a longer description of the variable FOO. ``show'' will show
6317 all of the variable descriptions and their current settings.
6319 confirm on/off: Enables warning questions for operations that are
6320 hard to recover from, e.g. rerunning the program while
6321 it is already running. Default is ON.
6323 editing on/off: Enables EMACS style command line editing
6324 of input. Previous lines can be recalled with
6325 control-P, the current line can be edited with control-B,
6326 you can search for commands with control-R, etc.
6329 history filename NAME: NAME is where the gdb command history
6330 will be stored. The default is .gdb_history,
6331 or the value of the environment variable
6334 history size N: The size, in commands, of the command history. The
6335 default is 256, or the value of the environment variable
6338 history save on/off: If this value is set to ON, the history file will
6339 be saved after exiting gdb. If set to OFF, the
6340 file will not be saved. The default is OFF.
6342 history expansion on/off: If this value is set to ON, then csh-like
6343 history expansion will be performed on
6344 command line input. The default is OFF.
6346 radix N: Sets the default radix for input and output. It can be set
6347 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6348 in the current radix, so "set radix 10" is always a no-op.
6350 height N: This integer value is the number of lines on a page. Default
6351 is 24, the current `stty rows'' setting, or the ``li#''
6352 setting from the termcap entry matching the environment
6355 width N: This integer value is the number of characters on a line.
6356 Default is 80, the current `stty cols'' setting, or the ``co#''
6357 setting from the termcap entry matching the environment
6360 Note: ``set screensize'' is obsolete. Use ``set height'' and
6361 ``set width'' instead.
6363 print address on/off: Print memory addresses in various command displays,
6364 such as stack traces and structure values. Gdb looks
6365 more ``symbolic'' if you turn this off; it looks more
6366 ``machine level'' with it on. Default is ON.
6368 print array on/off: Prettyprint arrays. New convenient format! Default
6371 print demangle on/off: Print C++ symbols in "source" form if on,
6374 print asm-demangle on/off: Same, for assembler level printouts
6377 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6380 * Support for Epoch Environment.
6382 The epoch environment is a version of Emacs v18 with windowing. One
6383 new command, ``inspect'', is identical to ``print'', except that if you
6384 are running in the epoch environment, the value is printed in its own
6388 * Support for Shared Libraries
6390 GDB can now debug programs and core files that use SunOS shared libraries.
6391 Symbols from a shared library cannot be referenced
6392 before the shared library has been linked with the program (this
6393 happens after you type ``run'' and before the function main() is entered).
6394 At any time after this linking (including when examining core files
6395 from dynamically linked programs), gdb reads the symbols from each
6396 shared library when you type the ``sharedlibrary'' command.
6397 It can be abbreviated ``share''.
6399 sharedlibrary REGEXP: Load shared object library symbols for files
6400 matching a unix regular expression. No argument
6401 indicates to load symbols for all shared libraries.
6403 info sharedlibrary: Status of loaded shared libraries.
6408 A watchpoint stops execution of a program whenever the value of an
6409 expression changes. Checking for this slows down execution
6410 tremendously whenever you are in the scope of the expression, but is
6411 quite useful for catching tough ``bit-spreader'' or pointer misuse
6412 problems. Some machines such as the 386 have hardware for doing this
6413 more quickly, and future versions of gdb will use this hardware.
6415 watch EXP: Set a watchpoint (breakpoint) for an expression.
6417 info watchpoints: Information about your watchpoints.
6419 delete N: Deletes watchpoint number N (same as breakpoints).
6420 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6421 enable N: Re-enables watchpoint number N (same as breakpoints).
6424 * C++ multiple inheritance
6426 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6429 * C++ exception handling
6431 Gdb now supports limited C++ exception handling. Besides the existing
6432 ability to breakpoint on an exception handler, gdb can breakpoint on
6433 the raising of an exception (before the stack is peeled back to the
6436 catch FOO: If there is a FOO exception handler in the dynamic scope,
6437 set a breakpoint to catch exceptions which may be raised there.
6438 Multiple exceptions (``catch foo bar baz'') may be caught.
6440 info catch: Lists all exceptions which may be caught in the
6441 current stack frame.
6444 * Minor command changes
6446 The command ``call func (arg, arg, ...)'' now acts like the print
6447 command, except it does not print or save a value if the function's result
6448 is void. This is similar to dbx usage.
6450 The ``up'' and ``down'' commands now always print the frame they end up
6451 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6452 frames without printing.
6454 * New directory command
6456 'dir' now adds directories to the FRONT of the source search path.
6457 The path starts off empty. Source files that contain debug information
6458 about the directory in which they were compiled can be found even
6459 with an empty path; Sun CC and GCC include this information. If GDB can't
6460 find your source file in the current directory, type "dir .".
6462 * Configuring GDB for compilation
6464 For normal use, type ``./configure host''. See README or gdb.texinfo
6467 GDB now handles cross debugging. If you are remotely debugging between
6468 two different machines, type ``./configure host -target=targ''.
6469 Host is the machine where GDB will run; targ is the machine
6470 where the program that you are debugging will run.
projects / external / binutils.git / blob