1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.12
6 * GDB now supports access to the PKU register on GNU/Linux. The register is
7 added by the Memory Protection Keys for Userspace feature which will be
8 available in future Intel CPUs.
12 ** New functions to start, stop and access a running btrace recording.
14 * GDB now supports recording and replaying rdrand and rdseed Intel 64
17 * Building GDB and GDBserver now requires a C++11 compiler.
19 For example, GCC 4.8 or later.
21 It is no longer possible to build GDB or GDBserver with a C
22 compiler. The --disable-build-with-cxx configure option has been
25 * Building GDB and GDBserver now requires GNU make >= 3.81.
27 It is no longer supported to build GDB or GDBserver with another
28 implementation of the make program or an earlier version of GNU make.
30 * Native debugging on MS-Windows supports command-line redirection
32 Command-line arguments used for starting programs on MS-Windows can
33 now include redirection symbols supported by native Windows shells,
34 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
35 as "run", "start", and "set args", as well as the corresponding MI
38 * Support for thread names on MS-Windows.
40 GDB now catches and handles the special exception that programs
41 running on MS-Windows use to assign names to threads in the
44 * Support for Java programs compiled with gcj has been removed.
46 * User commands now accept an unlimited number of arguments.
47 Previously, only up to 10 was accepted.
49 * The "eval" command now expands user-defined command arguments.
51 This makes it easier to process a variable number of arguments:
56 eval "print $arg%d", $i
61 * Target descriptions can now describe registers for sparc32 and sparc64.
63 * New native configurations
65 FreeBSD/mips mips*-*-freebsd
70 Synopsys ARC arc*-*-elf32
71 FreeBSD/mips mips*-*-freebsd
76 Erases all the flash memory regions reported by the target.
81 Erases all the flash memory regions reported by the target. This is
82 equivalent to the CLI command flash-erase.
84 *** Changes in GDB 7.12
86 * GDB and GDBserver now build with a C++ compiler by default.
88 The --enable-build-with-cxx configure option is now enabled by
89 default. One must now explicitly configure with
90 --disable-build-with-cxx in order to build with a C compiler. This
91 option will be removed in a future release.
93 * GDBserver now supports recording btrace without maintaining an active
96 * GDB now supports a negative repeat count in the 'x' command to examine
97 memory backward from the given address. For example:
100 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
101 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
102 (gdb) x/-5i 0x0000000000400580
103 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
104 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
105 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
106 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
107 0x40057b <main(int, char**)+25>:
108 callq 0x400536 <Func1(int, char const*)>
110 * Fortran: Support structures with fields of dynamic types and
111 arrays of dynamic types.
113 * The symbol dumping maintenance commands have new syntax.
114 maint print symbols [-pc address] [--] [filename]
115 maint print symbols [-objfile objfile] [-source source] [--] [filename]
116 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
117 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
118 maint print msymbols [-objfile objfile] [--] [filename]
120 * GDB now supports multibit bitfields and enums in target register
123 * New Python-based convenience function $_as_string(val), which returns
124 the textual representation of a value. This function is especially
125 useful to obtain the text label of an enum value.
127 * Intel MPX bound violation handling.
129 Segmentation faults caused by a Intel MPX boundary violation
130 now display the kind of violation (upper or lower), the memory
131 address accessed and the memory bounds, along with the usual
132 signal received and code location.
136 Program received signal SIGSEGV, Segmentation fault
137 Upper bound violation while accessing address 0x7fffffffc3b3
138 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
139 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
141 * Rust language support.
142 GDB now supports debugging programs written in the Rust programming
143 language. See https://www.rust-lang.org/ for more information about
146 * Support for running interpreters on specified input/output devices
148 GDB now supports a new mechanism that allows frontends to provide
149 fully featured GDB console views, as a better alternative to
150 building such views on top of the "-interpreter-exec console"
151 command. See the new "new-ui" command below. With that command,
152 frontends can now start GDB in the traditional command-line mode
153 running in an embedded terminal emulator widget, and create a
154 separate MI interpreter running on a specified i/o device. In this
155 way, GDB handles line editing, history, tab completion, etc. in the
156 console all by itself, and the GUI uses the separate MI interpreter
157 for its own control and synchronization, invisible to the command
160 * The "catch syscall" command catches groups of related syscalls.
162 The "catch syscall" command now supports catching a group of related
163 syscalls using the 'group:' or 'g:' prefix.
168 skip -gfile file-glob-pattern
169 skip -function function
170 skip -rfunction regular-expression
171 A generalized form of the skip command, with new support for
172 glob-style file names and regular expressions for function names.
173 Additionally, a file spec and a function spec may now be combined.
175 maint info line-table REGEXP
176 Display the contents of GDB's internal line table data struture.
179 Run any GDB unit tests that were compiled in.
182 Start a new user interface instance running INTERP as interpreter,
183 using the TTY file for input/output.
187 ** gdb.Breakpoint objects have a new attribute "pending", which
188 indicates whether the breakpoint is pending.
189 ** Three new breakpoint-related events have been added:
190 gdb.breakpoint_created, gdb.breakpoint_modified, and
191 gdb.breakpoint_deleted.
194 Signal ("set") the given MS-Windows event object. This is used in
195 conjunction with the Windows JIT debugging (AeDebug) support, where
196 the OS suspends a crashing process until a debugger can attach to
197 it. Resuming the crashing process, in order to debug it, is done by
200 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
201 was added in GDBserver, including JIT compiling fast tracepoint's
202 conditional expression bytecode into native code.
204 * Support for various remote target protocols and ROM monitors has
207 target m32rsdi Remote M32R debugging over SDI
208 target mips MIPS remote debugging protocol
209 target pmon PMON ROM monitor
210 target ddb NEC's DDB variant of PMON for Vr4300
211 target rockhopper NEC RockHopper variant of PMON
212 target lsi LSI variant of PMO
214 * Support for tracepoints and fast tracepoints on powerpc-linux,
215 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
216 including JIT compiling fast tracepoint's conditional expression
217 bytecode into native code.
219 * MI async record =record-started now includes the method and format used for
220 recording. For example:
222 =record-started,thread-group="i1",method="btrace",format="bts"
224 * MI async record =thread-selected now includes the frame field. For example:
226 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
230 Andes NDS32 nds32*-*-elf
232 *** Changes in GDB 7.11
234 * GDB now supports debugging kernel-based threads on FreeBSD.
236 * Per-inferior thread numbers
238 Thread numbers are now per inferior instead of global. If you're
239 debugging multiple inferiors, GDB displays thread IDs using a
240 qualified INF_NUM.THR_NUM form. For example:
244 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
245 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
246 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
247 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
249 As consequence, thread numbers as visible in the $_thread
250 convenience variable and in Python's InferiorThread.num attribute
251 are no longer unique between inferiors.
253 GDB now maintains a second thread ID per thread, referred to as the
254 global thread ID, which is the new equivalent of thread numbers in
255 previous releases. See also $_gthread below.
257 For backwards compatibility, MI's thread IDs always refer to global
260 * Commands that accept thread IDs now accept the qualified
261 INF_NUM.THR_NUM form as well. For example:
264 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
267 * In commands that accept a list of thread IDs, you can now refer to
268 all threads of an inferior using a star wildcard. GDB accepts
269 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
270 refer to all threads of the current inferior. For example, "info
273 * You can use "info threads -gid" to display the global thread ID of
276 * The new convenience variable $_gthread holds the global number of
279 * The new convenience variable $_inferior holds the number of the
282 * GDB now displays the ID and name of the thread that hit a breakpoint
283 or received a signal, if your program is multi-threaded. For
286 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
287 Thread 1 "main" received signal SIGINT, Interrupt.
289 * Record btrace now supports non-stop mode.
291 * Support for tracepoints on aarch64-linux was added in GDBserver.
293 * The 'record instruction-history' command now indicates speculative execution
294 when using the Intel Processor Trace recording format.
296 * GDB now allows users to specify explicit locations, bypassing
297 the linespec parser. This feature is also available to GDB/MI
300 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
301 GDB now is able to debug both AArch64 applications and ARM applications
304 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
305 including JIT compiling fast tracepoint's conditional expression bytecode
308 * GDB now supports displaced stepping on AArch64 GNU/Linux.
310 * "info threads", "info inferiors", "info display", "info checkpoints"
311 and "maint info program-spaces" now list the corresponding items in
312 ascending ID order, for consistency with all other "info" commands.
314 * In Ada, the overloads selection menu has been enhanced to display the
315 parameter types and the return types for the matching overloaded subprograms.
319 maint set target-non-stop (on|off|auto)
320 maint show target-non-stop
321 Control whether GDB targets always operate in non-stop mode even if
322 "set non-stop" is "off". The default is "auto", meaning non-stop
323 mode is enabled if supported by the target.
325 maint set bfd-sharing
326 maint show bfd-sharing
327 Control the reuse of bfd objects.
331 Control display of debugging info regarding bfd caching.
335 Control display of debugging info regarding FreeBSD threads.
337 set remote multiprocess-extensions-packet
338 show remote multiprocess-extensions-packet
339 Set/show the use of the remote protocol multiprocess extensions.
341 set remote thread-events
342 show remote thread-events
343 Set/show the use of thread create/exit events.
345 set ada print-signatures on|off
346 show ada print-signatures"
347 Control whether parameter types and return types are displayed in overloads
348 selection menus. It is activaled (@code{on}) by default.
352 Controls the maximum size of memory, in bytes, that GDB will
353 allocate for value contents. Prevents incorrect programs from
354 causing GDB to allocate overly large buffers. Default is 64k.
356 * The "disassemble" command accepts a new modifier: /s.
357 It prints mixed source+disassembly like /m with two differences:
358 - disassembled instructions are now printed in program order, and
359 - and source for all relevant files is now printed.
360 The "/m" option is now considered deprecated: its "source-centric"
361 output hasn't proved useful in practice.
363 * The "record instruction-history" command accepts a new modifier: /s.
364 It behaves exactly like /m and prints mixed source+disassembly.
366 * The "set scheduler-locking" command supports a new mode "replay".
367 It behaves like "off" in record mode and like "on" in replay mode.
369 * Support for various ROM monitors has been removed:
371 target dbug dBUG ROM monitor for Motorola ColdFire
372 target picobug Motorola picobug monitor
373 target dink32 DINK32 ROM monitor for PowerPC
374 target m32r Renesas M32R/D ROM monitor
375 target mon2000 mon2000 ROM monitor
376 target ppcbug PPCBUG ROM monitor for PowerPC
378 * Support for reading/writing memory and extracting values on architectures
379 whose memory is addressable in units of any integral multiple of 8 bits.
384 Indicates that an exec system call was executed.
386 exec-events feature in qSupported
387 The qSupported packet allows GDB to request support for exec
388 events using the new 'gdbfeature' exec-event, and the qSupported
389 response can contain the corresponding 'stubfeature'. Set and
390 show commands can be used to display whether these features are enabled.
393 Equivalent to interrupting with the ^C character, but works in
396 thread created stop reason (T05 create:...)
397 Indicates that the thread was just created and is stopped at entry.
399 thread exit stop reply (w exitcode;tid)
400 Indicates that the thread has terminated.
403 Enables/disables thread create and exit event reporting. For
404 example, this is used in non-stop mode when GDB stops a set of
405 threads and synchronously waits for the their corresponding stop
406 replies. Without exit events, if one of the threads exits, GDB
407 would hang forever not knowing that it should no longer expect a
408 stop for that same thread.
411 Indicates that there are no resumed threads left in the target (all
412 threads are stopped). The remote stub reports support for this stop
413 reply to GDB's qSupported query.
416 Enables/disables catching syscalls from the inferior process.
417 The remote stub reports support for this packet to GDB's qSupported query.
419 syscall_entry stop reason
420 Indicates that a syscall was just called.
422 syscall_return stop reason
423 Indicates that a syscall just returned.
425 * Extended-remote exec events
427 ** GDB now has support for exec events on extended-remote Linux targets.
428 For such targets with Linux kernels 2.5.46 and later, this enables
429 follow-exec-mode and exec catchpoints.
431 set remote exec-event-feature-packet
432 show remote exec-event-feature-packet
433 Set/show the use of the remote exec event feature.
435 * Thread names in remote protocol
437 The reply to qXfer:threads:read may now include a name attribute for each
440 * Target remote mode fork and exec events
442 ** GDB now has support for fork and exec events on target remote mode
443 Linux targets. For such targets with Linux kernels 2.5.46 and later,
444 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
445 fork and exec catchpoints.
447 * Remote syscall events
449 ** GDB now has support for catch syscall on remote Linux targets,
450 currently enabled on x86/x86_64 architectures.
452 set remote catch-syscall-packet
453 show remote catch-syscall-packet
454 Set/show the use of the remote catch syscall feature.
458 ** The -var-set-format command now accepts the zero-hexadecimal
459 format. It outputs data in hexadecimal format with zero-padding on the
464 ** gdb.InferiorThread objects have a new attribute "global_num",
465 which refers to the thread's global thread ID. The existing
466 "num" attribute now refers to the thread's per-inferior number.
467 See "Per-inferior thread numbers" above.
468 ** gdb.InferiorThread objects have a new attribute "inferior", which
469 is the Inferior object the thread belongs to.
471 *** Changes in GDB 7.10
473 * Support for process record-replay and reverse debugging on aarch64*-linux*
474 targets has been added. GDB now supports recording of A64 instruction set
475 including advance SIMD instructions.
477 * Support for Sun's version of the "stabs" debug file format has been removed.
479 * GDB now honors the content of the file /proc/PID/coredump_filter
480 (PID is the process ID) on GNU/Linux systems. This file can be used
481 to specify the types of memory mappings that will be included in a
482 corefile. For more information, please refer to the manual page of
483 "core(5)". GDB also has a new command: "set use-coredump-filter
484 on|off". It allows to set whether GDB will read the content of the
485 /proc/PID/coredump_filter file when generating a corefile.
487 * The "info os" command on GNU/Linux can now display information on
489 "info os cpus" Listing of all cpus/cores on the system
491 * GDB has two new commands: "set serial parity odd|even|none" and
492 "show serial parity". These allows to set or show parity for the
495 * The "info source" command now displays the producer string if it was
496 present in the debug info. This typically includes the compiler version
497 and may include things like its command line arguments.
499 * The "info dll", an alias of the "info sharedlibrary" command,
500 is now available on all platforms.
502 * Directory names supplied to the "set sysroot" commands may be
503 prefixed with "target:" to tell GDB to access shared libraries from
504 the target system, be it local or remote. This replaces the prefix
505 "remote:". The default sysroot has been changed from "" to
506 "target:". "remote:" is automatically converted to "target:" for
507 backward compatibility.
509 * The system root specified by "set sysroot" will be prepended to the
510 filename of the main executable (if reported to GDB as absolute by
511 the operating system) when starting processes remotely, and when
512 attaching to already-running local or remote processes.
514 * GDB now supports automatic location and retrieval of executable
515 files from remote targets. Remote debugging can now be initiated
516 using only a "target remote" or "target extended-remote" command
517 (no "set sysroot" or "file" commands are required). See "New remote
520 * The "dump" command now supports verilog hex format.
522 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
524 * On GNU/Linux, GDB and gdbserver are now able to access executable
525 and shared library files without a "set sysroot" command when
526 attaching to processes running in different mount namespaces from
527 the debugger. This makes it possible to attach to processes in
528 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
529 See "New remote packets" below.
531 * The "tui reg" command now provides completion for all of the
532 available register groups, including target specific groups.
534 * The HISTSIZE environment variable is no longer read when determining
535 the size of GDB's command history. GDB now instead reads the dedicated
536 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
537 disables truncation of command history. Non-numeric values of GDBHISTSIZE
542 ** Memory ports can now be unbuffered.
546 ** gdb.Objfile objects have a new attribute "username",
547 which is the name of the objfile as specified by the user,
548 without, for example, resolving symlinks.
549 ** You can now write frame unwinders in Python.
550 ** gdb.Type objects have a new method "optimized_out",
551 returning optimized out gdb.Value instance of this type.
552 ** gdb.Value objects have new methods "reference_value" and
553 "const_value" which return a reference to the value and a
554 "const" version of the value respectively.
558 maint print symbol-cache
559 Print the contents of the symbol cache.
561 maint print symbol-cache-statistics
562 Print statistics of symbol cache usage.
564 maint flush-symbol-cache
565 Flush the contents of the symbol cache.
569 Start branch trace recording using Branch Trace Store (BTS) format.
572 Evaluate expression by using the compiler and print result.
576 Explicit commands for enabling and disabling tui mode.
579 set mpx bound on i386 and amd64
580 Support for bound table investigation on Intel MPX enabled applications.
584 Start branch trace recording using Intel Processor Trace format.
587 Print information about branch tracing internals.
589 maint btrace packet-history
590 Print the raw branch tracing data.
592 maint btrace clear-packet-history
593 Discard the stored raw branch tracing data.
596 Discard all branch tracing data. It will be fetched and processed
597 anew by the next "record" command.
602 Renamed from "set debug dwarf2-die".
604 Renamed from "show debug dwarf2-die".
607 Renamed from "set debug dwarf2-read".
608 show debug dwarf-read
609 Renamed from "show debug dwarf2-read".
611 maint set dwarf always-disassemble
612 Renamed from "maint set dwarf2 always-disassemble".
613 maint show dwarf always-disassemble
614 Renamed from "maint show dwarf2 always-disassemble".
616 maint set dwarf max-cache-age
617 Renamed from "maint set dwarf2 max-cache-age".
618 maint show dwarf max-cache-age
619 Renamed from "maint show dwarf2 max-cache-age".
622 show debug dwarf-line
623 Control display of debugging info regarding DWARF line processing.
627 Set the maximum number of candidates to be considered during
628 completion. The default value is 200. This limit allows GDB
629 to avoid generating large completion lists, the computation of
630 which can cause the debugger to become temporarily unresponsive.
632 set history remove-duplicates
633 show history remove-duplicates
634 Control the removal of duplicate history entries.
636 maint set symbol-cache-size
637 maint show symbol-cache-size
638 Control the size of the symbol cache.
640 set|show record btrace bts buffer-size
641 Set and show the size of the ring buffer used for branch tracing in
643 The obtained size may differ from the requested size. Use "info
644 record" to see the obtained buffer size.
646 set debug linux-namespaces
647 show debug linux-namespaces
648 Control display of debugging info regarding Linux namespaces.
650 set|show record btrace pt buffer-size
651 Set and show the size of the ring buffer used for branch tracing in
652 Intel Processor Trace format.
653 The obtained size may differ from the requested size. Use "info
654 record" to see the obtained buffer size.
656 maint set|show btrace pt skip-pad
657 Set and show whether PAD packets are skipped when computing the
660 * The command 'thread apply all' can now support new option '-ascending'
661 to call its specified command for all threads in ascending order.
663 * Python/Guile scripting
665 ** GDB now supports auto-loading of Python/Guile scripts contained in the
666 special section named `.debug_gdb_scripts'.
670 qXfer:btrace-conf:read
671 Return the branch trace configuration for the current thread.
673 Qbtrace-conf:bts:size
674 Set the requested ring buffer size for branch tracing in BTS format.
677 Enable Intel Procesor Trace-based branch tracing for the current
678 process. The remote stub reports support for this packet to GDB's
682 Set the requested ring buffer size for branch tracing in Intel Processor
686 Indicates a memory breakpoint instruction was executed, irrespective
687 of whether it was GDB that planted the breakpoint or the breakpoint
688 is hardcoded in the program. This is required for correct non-stop
692 Indicates the target stopped for a hardware breakpoint. This is
693 required for correct non-stop mode operation.
696 Return information about files on the remote system.
699 Return the full absolute name of the file that was executed to
700 create a process running on the remote system.
703 Select the filesystem on which vFile: operations with filename
704 arguments will operate. This is required for GDB to be able to
705 access files on remote targets where the remote stub does not
706 share a common filesystem with the inferior(s).
709 Indicates that a fork system call was executed.
712 Indicates that a vfork system call was executed.
714 vforkdone stop reason
715 Indicates that a vfork child of the specified process has executed
716 an exec or exit, allowing the vfork parent to resume execution.
718 fork-events and vfork-events features in qSupported
719 The qSupported packet allows GDB to request support for fork and
720 vfork events using new 'gdbfeatures' fork-events and vfork-events,
721 and the qSupported response can contain the corresponding
722 'stubfeatures'. Set and show commands can be used to display
723 whether these features are enabled.
725 * Extended-remote fork events
727 ** GDB now has support for fork events on extended-remote Linux
728 targets. For targets with Linux kernels 2.5.60 and later, this
729 enables follow-fork-mode and detach-on-fork for both fork and
730 vfork, as well as fork and vfork catchpoints.
732 * The info record command now shows the recording format and the
733 branch tracing configuration for the current thread when using
734 the btrace record target.
735 For the BTS format, it shows the ring buffer size.
737 * GDB now has support for DTrace USDT (Userland Static Defined
738 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
740 * GDB now supports access to vector registers on S/390 GNU/Linux
743 * Removed command line options
745 -xdb HP-UX XDB compatibility mode.
747 * Removed targets and native configurations
749 HP/PA running HP-UX hppa*-*-hpux*
750 Itanium running HP-UX ia64-*-hpux*
752 * New configure options
755 This configure option allows the user to build GDB with support for
756 Intel Processor Trace (default: auto). This requires libipt.
758 --with-libipt-prefix=PATH
759 Specify the path to the version of libipt that GDB should use.
760 $PATH/include should contain the intel-pt.h header and
761 $PATH/lib should contain the libipt.so library.
763 *** Changes in GDB 7.9.1
767 ** Xmethods can now specify a result type.
769 *** Changes in GDB 7.9
771 * GDB now supports hardware watchpoints on x86 GNU Hurd.
775 ** You can now access frame registers from Python scripts.
776 ** New attribute 'producer' for gdb.Symtab objects.
777 ** gdb.Objfile objects have a new attribute "progspace",
778 which is the gdb.Progspace object of the containing program space.
779 ** gdb.Objfile objects have a new attribute "owner".
780 ** gdb.Objfile objects have a new attribute "build_id",
781 which is the build ID generated when the file was built.
782 ** gdb.Objfile objects have a new method "add_separate_debug_file".
783 ** A new event "gdb.clear_objfiles" has been added, triggered when
784 selecting a new file to debug.
785 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
786 ** New function gdb.lookup_objfile.
788 New events which are triggered when GDB modifies the state of the
791 ** gdb.events.inferior_call_pre: Function call is about to be made.
792 ** gdb.events.inferior_call_post: Function call has just been made.
793 ** gdb.events.memory_changed: A memory location has been altered.
794 ** gdb.events.register_changed: A register has been altered.
796 * New Python-based convenience functions:
798 ** $_caller_is(name [, number_of_frames])
799 ** $_caller_matches(regexp [, number_of_frames])
800 ** $_any_caller_is(name [, number_of_frames])
801 ** $_any_caller_matches(regexp [, number_of_frames])
803 * GDB now supports the compilation and injection of source code into
804 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
805 to compile the source code to object code, and if successful, inject
806 and execute that code within the current context of the inferior.
807 Currently the C language is supported. The commands used to
808 interface with this new feature are:
810 compile code [-raw|-r] [--] [source code]
811 compile file [-raw|-r] filename
815 demangle [-l language] [--] name
816 Demangle "name" in the specified language, or the current language
817 if elided. This command is renamed from the "maint demangle" command.
818 The latter is kept as a no-op to avoid "maint demangle" being interpreted
819 as "maint demangler-warning".
821 queue-signal signal-name-or-number
822 Queue a signal to be delivered to the thread when it is resumed.
824 add-auto-load-scripts-directory directory
825 Add entries to the list of directories from which to load auto-loaded
828 maint print user-registers
829 List all currently available "user" registers.
831 compile code [-r|-raw] [--] [source code]
832 Compile, inject, and execute in the inferior the executable object
833 code produced by compiling the provided source code.
835 compile file [-r|-raw] filename
836 Compile and inject into the inferior the executable object code
837 produced by compiling the source code stored in the filename
840 * On resume, GDB now always passes the signal the program had stopped
841 for to the thread the signal was sent to, even if the user changed
842 threads before resuming. Previously GDB would often (but not
843 always) deliver the signal to the thread that happens to be current
846 * Conversely, the "signal" command now consistently delivers the
847 requested signal to the current thread. GDB now asks for
848 confirmation if the program had stopped for a signal and the user
849 switched threads meanwhile.
851 * "breakpoint always-inserted" modes "off" and "auto" merged.
853 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
854 won't remove breakpoints from the target until all threads stop,
855 even in non-stop mode. The "auto" mode has been removed, and "off"
856 is now the default mode.
860 set debug symbol-lookup
861 show debug symbol-lookup
862 Control display of debugging info regarding symbol lookup.
866 ** The -list-thread-groups command outputs an exit-code field for
867 inferiors that have exited.
871 MIPS SDE mips*-sde*-elf*
875 Support for these obsolete configurations has been removed.
877 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
878 SGI Irix-5.x mips-*-irix5*
879 SGI Irix-6.x mips-*-irix6*
880 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
881 VAX running Ultrix vax-*-ultrix*
883 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
884 and "assf"), have been removed. Use the "sharedlibrary" command, or
885 its alias "share", instead.
887 *** Changes in GDB 7.8
889 * New command line options
892 This is an alias for the --data-directory option.
894 * GDB supports printing and modifying of variable length automatic arrays
895 as specified in ISO C99.
897 * The ARM simulator now supports instruction level tracing
898 with or without disassembly.
902 GDB now has support for scripting using Guile. Whether this is
903 available is determined at configure time.
904 Guile version 2.0 or greater is required.
905 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
907 * New commands (for set/show, see "New options" below)
911 Invoke CODE by passing it to the Guile interpreter.
915 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
917 info auto-load guile-scripts [regexp]
918 Print the list of automatically loaded Guile scripts.
920 * The source command is now capable of sourcing Guile scripts.
921 This feature is dependent on the debugger being built with Guile support.
925 set print symbol-loading (off|brief|full)
926 show print symbol-loading
927 Control whether to print informational messages when loading symbol
928 information for a file. The default is "full", but when debugging
929 programs with large numbers of shared libraries the amount of output
932 set guile print-stack (none|message|full)
933 show guile print-stack
934 Show a stack trace when an error is encountered in a Guile script.
936 set auto-load guile-scripts (on|off)
937 show auto-load guile-scripts
938 Control auto-loading of Guile script files.
940 maint ada set ignore-descriptive-types (on|off)
941 maint ada show ignore-descriptive-types
942 Control whether the debugger should ignore descriptive types in Ada
943 programs. The default is not to ignore the descriptive types. See
944 the user manual for more details on descriptive types and the intended
945 usage of this option.
947 set auto-connect-native-target
949 Control whether GDB is allowed to automatically connect to the
950 native target for the run, attach, etc. commands when not connected
951 to any target yet. See also "target native" below.
953 set record btrace replay-memory-access (read-only|read-write)
954 show record btrace replay-memory-access
955 Control what memory accesses are allowed during replay.
957 maint set target-async (on|off)
958 maint show target-async
959 This controls whether GDB targets operate in synchronous or
960 asynchronous mode. Normally the default is asynchronous, if it is
961 available; but this can be changed to more easily debug problems
962 occurring only in synchronous mode.
964 set mi-async (on|off)
966 Control whether MI asynchronous mode is preferred. This supersedes
967 "set target-async" of previous GDB versions.
969 * "set target-async" is deprecated as a CLI option and is now an alias
970 for "set mi-async" (only puts MI into async mode).
972 * Background execution commands (e.g., "c&", "s&", etc.) are now
973 possible ``out of the box'' if the target supports them. Previously
974 the user would need to explicitly enable the possibility with the
975 "set target-async on" command.
977 * New features in the GDB remote stub, GDBserver
979 ** New option --debug-format=option1[,option2,...] allows one to add
980 additional text to each output. At present only timestamps
981 are supported: --debug-format=timestamps.
982 Timestamps can also be turned on with the
983 "monitor set debug-format timestamps" command from GDB.
985 * The 'record instruction-history' command now starts counting instructions
986 at one. This also affects the instruction ranges reported by the
987 'record function-call-history' command when given the /i modifier.
989 * The command 'record function-call-history' supports a new modifier '/c' to
990 indent the function names based on their call stack depth.
991 The fields for the '/i' and '/l' modifier have been reordered.
992 The source line range is now prefixed with 'at'.
993 The instruction range is now prefixed with 'inst'.
994 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
995 "record instruction-history" and "list" commands.
997 * The ranges given as arguments to the 'record function-call-history' and
998 'record instruction-history' commands are now inclusive.
1000 * The btrace record target now supports the 'record goto' command.
1001 For locations inside the execution trace, the back trace is computed
1002 based on the information stored in the execution trace.
1004 * The btrace record target supports limited reverse execution and replay.
1005 The target does not record data and therefore does not allow reading
1006 memory or registers.
1008 * The "catch syscall" command now works on s390*-linux* targets.
1010 * The "compare-sections" command is no longer specific to target
1011 remote. It now works with all targets.
1013 * All native targets are now consistently called "native".
1014 Consequently, the "target child", "target GNU", "target djgpp",
1015 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1016 commands have been replaced with "target native". The QNX/NTO port
1017 leaves the "procfs" target in place and adds a "native" target for
1018 consistency with other ports. The impact on users should be minimal
1019 as these commands previously either throwed an error, or were
1020 no-ops. The target's name is visible in the output of the following
1021 commands: "help target", "info target", "info files", "maint print
1024 * The "target native" command now connects to the native target. This
1025 can be used to launch native programs even when "set
1026 auto-connect-native-target" is set to off.
1028 * GDB now supports access to Intel MPX registers on GNU/Linux.
1030 * Support for Intel AVX-512 registers on GNU/Linux.
1031 Support displaying and modifying Intel AVX-512 registers
1032 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1034 * New remote packets
1036 qXfer:btrace:read's annex
1037 The qXfer:btrace:read packet supports a new annex 'delta' to read
1038 branch trace incrementally.
1042 ** Valid Python operations on gdb.Value objects representing
1043 structs/classes invoke the corresponding overloaded operators if
1045 ** New `Xmethods' feature in the Python API. Xmethods are
1046 additional methods or replacements for existing methods of a C++
1047 class. This feature is useful for those cases where a method
1048 defined in C++ source code could be inlined or optimized out by
1049 the compiler, making it unavailable to GDB.
1052 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1054 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1055 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1056 its alias "share", instead.
1058 * The commands "set remotebaud" and "show remotebaud" are no longer
1059 supported. Use "set serial baud" and "show serial baud" (respectively)
1064 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1065 target-async". The latter is left as a deprecated alias of the
1066 former for backward compatibility. If the target supports it,
1067 CLI background execution commands are now always possible by
1068 default, independently of whether the frontend stated a
1069 preference for asynchronous execution with "-gdb-set mi-async".
1070 Previously "-gdb-set target-async off" affected both MI execution
1071 commands and CLI execution commands.
1073 *** Changes in GDB 7.7
1075 * Improved support for process record-replay and reverse debugging on
1076 arm*-linux* targets. Support for thumb32 and syscall instruction
1077 recording has been added.
1079 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1081 * GDB now supports Fission DWP file format version 2.
1082 http://gcc.gnu.org/wiki/DebugFission
1084 * New convenience function "$_isvoid", to check whether an expression
1085 is void. A void expression is an expression where the type of the
1086 result is "void". For example, some convenience variables may be
1087 "void" when evaluated (e.g., "$_exitcode" before the execution of
1088 the program being debugged; or an undefined convenience variable).
1089 Another example, when calling a function whose return type is
1092 * The "maintenance print objfiles" command now takes an optional regexp.
1094 * The "catch syscall" command now works on arm*-linux* targets.
1096 * GDB now consistently shows "<not saved>" when printing values of
1097 registers the debug info indicates have not been saved in the frame
1098 and there's nowhere to retrieve them from
1099 (callee-saved/call-clobbered registers):
1104 (gdb) info registers rax
1107 Before, the former would print "<optimized out>", and the latter
1108 "*value not available*".
1110 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1115 ** Frame filters and frame decorators have been added.
1116 ** Temporary breakpoints are now supported.
1117 ** Line tables representation has been added.
1118 ** New attribute 'parent_type' for gdb.Field objects.
1119 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1120 ** New attribute 'name' for gdb.Type objects.
1124 Nios II ELF nios2*-*-elf
1125 Nios II GNU/Linux nios2*-*-linux
1126 Texas Instruments MSP430 msp430*-*-elf
1128 * Removed native configurations
1130 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1131 been removed. ELF variants of these configurations are kept supported.
1133 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1134 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1135 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1136 i[34567]86-*-openbsd3.[0-3]
1137 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1138 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1139 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1143 Like "catch throw", but catches a re-thrown exception.
1144 maint check-psymtabs
1145 Renamed from old "maint check-symtabs".
1147 Perform consistency checks on symtabs.
1148 maint expand-symtabs
1149 Expand symtabs matching an optional regexp.
1152 Display the details of GDB configure-time options.
1154 maint set|show per-command
1155 maint set|show per-command space
1156 maint set|show per-command time
1157 maint set|show per-command symtab
1158 Enable display of per-command gdb resource usage.
1160 remove-symbol-file FILENAME
1161 remove-symbol-file -a ADDRESS
1162 Remove a symbol file added via add-symbol-file. The file to remove
1163 can be identified by its filename or by an address that lies within
1164 the boundaries of this symbol file in memory.
1167 info exceptions REGEXP
1168 Display the list of Ada exceptions defined in the program being
1169 debugged. If provided, only the exceptions whose names match REGEXP
1174 set debug symfile off|on
1176 Control display of debugging info regarding reading symbol files and
1177 symbol tables within those files
1179 set print raw frame-arguments
1180 show print raw frame-arguments
1181 Set/show whether to print frame arguments in raw mode,
1182 disregarding any defined pretty-printers.
1184 set remote trace-status-packet
1185 show remote trace-status-packet
1186 Set/show the use of remote protocol qTStatus packet.
1190 Control display of debugging messages related to Nios II targets.
1194 Control whether target-assisted range stepping is enabled.
1196 set startup-with-shell
1197 show startup-with-shell
1198 Specifies whether Unix child processes are started via a shell or
1203 Use the target memory cache for accesses to the code segment. This
1204 improves performance of remote debugging (particularly disassembly).
1206 * You can now use a literal value 'unlimited' for options that
1207 interpret 0 or -1 as meaning "unlimited". E.g., "set
1208 trace-buffer-size unlimited" is now an alias for "set
1209 trace-buffer-size -1" and "set height unlimited" is now an alias for
1212 * The "set debug symtab-create" debugging option of GDB has been changed to
1213 accept a verbosity level. 0 means "off", 1 provides basic debugging
1214 output, and values of 2 or greater provides more verbose output.
1216 * New command-line options
1218 Display the details of GDB configure-time options.
1220 * The command 'tsave' can now support new option '-ctf' to save trace
1221 buffer in Common Trace Format.
1223 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1226 * GDB now implements the the C++ 'typeid' operator.
1228 * The new convenience variable $_exception holds the exception being
1229 thrown or caught at an exception-related catchpoint.
1231 * The exception-related catchpoints, like "catch throw", now accept a
1232 regular expression which can be used to filter exceptions by type.
1234 * The new convenience variable $_exitsignal is automatically set to
1235 the terminating signal number when the program being debugged dies
1236 due to an uncaught signal.
1240 ** All MI commands now accept an optional "--language" option.
1241 Support for this feature can be verified by using the "-list-features"
1242 command, which should contain "language-option".
1244 ** The new command -info-gdb-mi-command allows the user to determine
1245 whether a GDB/MI command is supported or not.
1247 ** The "^error" result record returned when trying to execute an undefined
1248 GDB/MI command now provides a variable named "code" whose content is the
1249 "undefined-command" error code. Support for this feature can be verified
1250 by using the "-list-features" command, which should contain
1251 "undefined-command-error-code".
1253 ** The -trace-save MI command can optionally save trace buffer in Common
1256 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1258 ** The command -data-list-register-values now accepts an optional
1259 "--skip-unavailable" option. When used, only the available registers
1262 ** The new command -trace-frame-collected dumps collected variables,
1263 computed expressions, tvars, memory and registers in a traceframe.
1265 ** The commands -stack-list-locals, -stack-list-arguments and
1266 -stack-list-variables now accept an option "--skip-unavailable".
1267 When used, only the available locals or arguments are displayed.
1269 ** The -exec-run command now accepts an optional "--start" option.
1270 When used, the command follows the same semantics as the "start"
1271 command, stopping the program's execution at the start of its
1272 main subprogram. Support for this feature can be verified using
1273 the "-list-features" command, which should contain
1274 "exec-run-start-option".
1276 ** The new commands -catch-assert and -catch-exceptions insert
1277 catchpoints stopping the program when Ada exceptions are raised.
1279 ** The new command -info-ada-exceptions provides the equivalent of
1280 the new "info exceptions" command.
1282 * New system-wide configuration scripts
1283 A GDB installation now provides scripts suitable for use as system-wide
1284 configuration scripts for the following systems:
1288 * GDB now supports target-assigned range stepping with remote targets.
1289 This improves the performance of stepping source lines by reducing
1290 the number of control packets from/to GDB. See "New remote packets"
1293 * GDB now understands the element 'tvar' in the XML traceframe info.
1294 It has the id of the collected trace state variables.
1296 * On S/390 targets that provide the transactional-execution feature,
1297 the program interruption transaction diagnostic block (TDB) is now
1298 represented as a number of additional "registers" in GDB.
1300 * New remote packets
1304 The vCont packet supports a new 'r' action, that tells the remote
1305 stub to step through an address range itself, without GDB
1306 involvemement at each single-step.
1308 qXfer:libraries-svr4:read's annex
1309 The previously unused annex of the qXfer:libraries-svr4:read packet
1310 is now used to support passing an argument list. The remote stub
1311 reports support for this argument list to GDB's qSupported query.
1312 The defined arguments are "start" and "prev", used to reduce work
1313 necessary for library list updating, resulting in significant
1316 * New features in the GDB remote stub, GDBserver
1318 ** GDBserver now supports target-assisted range stepping. Currently
1319 enabled on x86/x86_64 GNU/Linux targets.
1321 ** GDBserver now adds element 'tvar' in the XML in the reply to
1322 'qXfer:traceframe-info:read'. It has the id of the collected
1323 trace state variables.
1325 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1328 * New 'z' formatter for printing and examining memory, this displays the
1329 value as hexadecimal zero padded on the left to the size of the type.
1331 * GDB can now use Windows x64 unwinding data.
1333 * The "set remotebaud" command has been replaced by "set serial baud".
1334 Similarly, "show remotebaud" has been replaced by "show serial baud".
1335 The "set remotebaud" and "show remotebaud" commands are still available
1336 to provide backward compatibility with older versions of GDB.
1338 *** Changes in GDB 7.6
1340 * Target record has been renamed to record-full.
1341 Record/replay is now enabled with the "record full" command.
1342 This also affects settings that are associated with full record/replay
1343 that have been moved from "set/show record" to "set/show record full":
1345 set|show record full insn-number-max
1346 set|show record full stop-at-limit
1347 set|show record full memory-query
1349 * A new record target "record-btrace" has been added. The new target
1350 uses hardware support to record the control-flow of a process. It
1351 does not support replaying the execution, but it implements the
1352 below new commands for investigating the recorded execution log.
1353 This new recording method can be enabled using:
1357 The "record-btrace" target is only available on Intel Atom processors
1358 and requires a Linux kernel 2.6.32 or later.
1360 * Two new commands have been added for record/replay to give information
1361 about the recorded execution without having to replay the execution.
1362 The commands are only supported by "record btrace".
1364 record instruction-history prints the execution history at
1365 instruction granularity
1367 record function-call-history prints the execution history at
1368 function granularity
1370 * New native configurations
1372 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1373 FreeBSD/powerpc powerpc*-*-freebsd
1374 x86_64/Cygwin x86_64-*-cygwin*
1375 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1379 ARM AArch64 aarch64*-*-elf
1380 ARM AArch64 GNU/Linux aarch64*-*-linux
1381 Lynx 178 PowerPC powerpc-*-lynx*178
1382 x86_64/Cygwin x86_64-*-cygwin*
1383 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1385 * If the configured location of system.gdbinit file (as given by the
1386 --with-system-gdbinit option at configure time) is in the
1387 data-directory (as specified by --with-gdb-datadir at configure
1388 time) or in one of its subdirectories, then GDB will look for the
1389 system-wide init file in the directory specified by the
1390 --data-directory command-line option.
1392 * New command line options:
1394 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1395 other initialization files, unlike -nx which disables all of them.
1397 * Removed command line options
1399 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1402 * The 'ptype' and 'whatis' commands now accept an argument to control
1405 * 'info proc' now works on some core files.
1409 ** Vectors can be created with gdb.Type.vector.
1411 ** Python's atexit.register now works in GDB.
1413 ** Types can be pretty-printed via a Python API.
1415 ** Python 3 is now supported (in addition to Python 2.4 or later)
1417 ** New class gdb.Architecture exposes GDB's internal representation
1418 of architecture in the Python API.
1420 ** New method Frame.architecture returns the gdb.Architecture object
1421 corresponding to the frame's architecture.
1423 * New Python-based convenience functions:
1425 ** $_memeq(buf1, buf2, length)
1426 ** $_streq(str1, str2)
1428 ** $_regex(str, regex)
1430 * The 'cd' command now defaults to using '~' (the home directory) if not
1433 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1434 default for GCC since November 2000.
1436 * The command 'forward-search' can now be abbreviated as 'fo'.
1438 * The command 'info tracepoints' can now display 'installed on target'
1439 or 'not installed on target' for each non-pending location of tracepoint.
1441 * New configure options
1443 --enable-libmcheck/--disable-libmcheck
1444 By default, development versions are built with -lmcheck on hosts
1445 that support it, in order to help track memory corruption issues.
1446 Release versions, on the other hand, are built without -lmcheck
1447 by default. The --enable-libmcheck/--disable-libmcheck configure
1448 options allow the user to override that default.
1449 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1450 This configure option allows the user to build GDB with
1451 libbabeltrace using which GDB can read Common Trace Format data.
1453 * New commands (for set/show, see "New options" below)
1456 Catch signals. This is similar to "handle", but allows commands and
1457 conditions to be attached.
1460 List the BFDs known to GDB.
1462 python-interactive [command]
1464 Start a Python interactive prompt, or evaluate the optional command
1465 and print the result of expressions.
1468 "py" is a new alias for "python".
1470 enable type-printer [name]...
1471 disable type-printer [name]...
1472 Enable or disable type printers.
1476 ** For the Renesas Super-H architecture, the "regs" command has been removed
1477 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1482 set print type methods (on|off)
1483 show print type methods
1484 Control whether method declarations are displayed by "ptype".
1485 The default is to show them.
1487 set print type typedefs (on|off)
1488 show print type typedefs
1489 Control whether typedef definitions are displayed by "ptype".
1490 The default is to show them.
1492 set filename-display basename|relative|absolute
1493 show filename-display
1494 Control the way in which filenames is displayed.
1495 The default is "relative", which preserves previous behavior.
1497 set trace-buffer-size
1498 show trace-buffer-size
1499 Request target to change the size of trace buffer.
1501 set remote trace-buffer-size-packet auto|on|off
1502 show remote trace-buffer-size-packet
1503 Control the use of the remote protocol `QTBuffer:size' packet.
1507 Control display of debugging messages related to ARM AArch64.
1510 set debug coff-pe-read
1511 show debug coff-pe-read
1512 Control display of debugging messages related to reading of COFF/PE
1517 Control display of debugging messages related to Mach-O symbols
1520 set debug notification
1521 show debug notification
1522 Control display of debugging info for async remote notification.
1526 ** Command parameter changes are now notified using new async record
1527 "=cmd-param-changed".
1528 ** Trace frame changes caused by command "tfind" are now notified using
1529 new async record "=traceframe-changed".
1530 ** The creation, deletion and modification of trace state variables
1531 are now notified using new async records "=tsv-created",
1532 "=tsv-deleted" and "=tsv-modified".
1533 ** The start and stop of process record are now notified using new
1534 async record "=record-started" and "=record-stopped".
1535 ** Memory changes are now notified using new async record
1537 ** The data-disassemble command response will include a "fullname" field
1538 containing the absolute file name when source has been requested.
1539 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1540 command, to allow pattern filling of memory areas.
1541 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1542 library load/unload events.
1543 ** The response to breakpoint commands and breakpoint async records
1544 includes an "installed" field containing a boolean state about each
1545 non-pending tracepoint location is whether installed on target or not.
1546 ** Output of the "-trace-status" command includes a "trace-file" field
1547 containing the name of the trace file being examined. This field is
1548 optional, and only present when examining a trace file.
1549 ** The "fullname" field is now always present along with the "file" field,
1550 even if the file cannot be found by GDB.
1552 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1553 You must have the LZMA library available when configuring GDB for this
1554 feature to be enabled. For more information, see:
1555 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1557 * New remote packets
1560 Set the size of trace buffer. The remote stub reports support for this
1561 packet to gdb's qSupported query.
1564 Enable Branch Trace Store (BTS)-based branch tracing for the current
1565 thread. The remote stub reports support for this packet to gdb's
1569 Disable branch tracing for the current thread. The remote stub reports
1570 support for this packet to gdb's qSupported query.
1573 Read the traced branches for the current thread. The remote stub
1574 reports support for this packet to gdb's qSupported query.
1576 *** Changes in GDB 7.5
1578 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1579 for more x32 ABI info.
1581 * GDB now supports access to MIPS DSP registers on Linux targets.
1583 * GDB now supports debugging microMIPS binaries.
1585 * The "info os" command on GNU/Linux can now display information on
1586 several new classes of objects managed by the operating system:
1587 "info os procgroups" lists process groups
1588 "info os files" lists file descriptors
1589 "info os sockets" lists internet-domain sockets
1590 "info os shm" lists shared-memory regions
1591 "info os semaphores" lists semaphores
1592 "info os msg" lists message queues
1593 "info os modules" lists loaded kernel modules
1595 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1596 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1597 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1598 options and inspect the probe arguments using the new $_probe_arg family
1599 of convenience variables. You can obtain more information about SystemTap
1600 in <http://sourceware.org/systemtap/>.
1602 * GDB now supports reversible debugging on ARM, it allows you to
1603 debug basic ARM and THUMB instructions, and provides
1604 record/replay support.
1606 * The option "symbol-reloading" has been deleted as it is no longer used.
1610 ** GDB commands implemented in Python can now be put in command class
1613 ** The "maint set python print-stack on|off" is now deleted.
1615 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1616 apply "flag enum"-style pretty-printing to any enum.
1618 ** gdb.lookup_symbol can now work when there is no current frame.
1620 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1621 the source at which the symbol was defined.
1623 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1624 method 'value'. The former indicates whether the symbol needs a
1625 frame in order to compute its value, and the latter computes the
1628 ** A new method 'referenced_value' on gdb.Value objects which can
1629 dereference pointer as well as C++ reference values.
1631 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1632 which return the global and static blocks (as gdb.Block objects),
1633 of the underlying symbol table, respectively.
1635 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1636 object associated with a PC value.
1638 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1639 of the address range occupied by code for the current source line.
1641 * Go language support.
1642 GDB now supports debugging programs written in the Go programming
1645 * GDBserver now supports stdio connections.
1646 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1648 * The binary "gdbtui" can no longer be built or installed.
1649 Use "gdb -tui" instead.
1651 * GDB will now print "flag" enums specially. A flag enum is one where
1652 all the enumerator values have no bits in common when pairwise
1653 "and"ed. When printing a value whose type is a flag enum, GDB will
1654 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1655 (gdb) print (enum E) 3
1658 * The filename part of a linespec will now match trailing components
1659 of a source file name. For example, "break gcc/expr.c:1000" will
1660 now set a breakpoint in build/gcc/expr.c, but not
1661 build/libcpp/expr.c.
1663 * The "info proc" and "generate-core-file" commands will now also
1664 work on remote targets connected to GDBserver on Linux.
1666 * The command "info catch" has been removed. It has been disabled
1667 since December 2007.
1669 * The "catch exception" and "catch assert" commands now accept
1670 a condition at the end of the command, much like the "break"
1671 command does. For instance:
1673 (gdb) catch exception Constraint_Error if Barrier = True
1675 Previously, it was possible to add a condition to such catchpoints,
1676 but it had to be done as a second step, after the catchpoint had been
1677 created, using the "condition" command.
1679 * The "info static-tracepoint-marker" command will now also work on
1680 native Linux targets with in-process agent.
1682 * GDB can now set breakpoints on inlined functions.
1684 * The .gdb_index section has been updated to include symbols for
1685 inlined functions. GDB will ignore older .gdb_index sections by
1686 default, which could cause symbol files to be loaded more slowly
1687 until their .gdb_index sections can be recreated. The new command
1688 "set use-deprecated-index-sections on" will cause GDB to use any older
1689 .gdb_index sections it finds. This will restore performance, but the
1690 ability to set breakpoints on inlined functions will be lost in symbol
1691 files with older .gdb_index sections.
1693 The .gdb_index section has also been updated to record more information
1694 about each symbol. This speeds up the "info variables", "info functions"
1695 and "info types" commands when used with programs having the .gdb_index
1696 section, as well as speeding up debugging with shared libraries using
1697 the .gdb_index section.
1699 * Ada support for GDB/MI Variable Objects has been added.
1701 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1706 ** New command -info-os is the MI equivalent of "info os".
1708 ** Output logs ("set logging" and related) now include MI output.
1712 ** "set use-deprecated-index-sections on|off"
1713 "show use-deprecated-index-sections on|off"
1714 Controls the use of deprecated .gdb_index sections.
1716 ** "catch load" and "catch unload" can be used to stop when a shared
1717 library is loaded or unloaded, respectively.
1719 ** "enable count" can be used to auto-disable a breakpoint after
1722 ** "info vtbl" can be used to show the virtual method tables for
1723 C++ and Java objects.
1725 ** "explore" and its sub commands "explore value" and "explore type"
1726 can be used to recursively explore values and types of
1727 expressions. These commands are available only if GDB is
1728 configured with '--with-python'.
1730 ** "info auto-load" shows status of all kinds of auto-loaded files,
1731 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1732 sequences of commands files, "info auto-load python-scripts"
1733 shows status of auto-loading Python script files,
1734 "info auto-load local-gdbinit" shows status of loading init file
1735 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1736 status of inferior specific thread debugging shared library loading.
1738 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1739 and "show auto-load-scripts" commands have been deprecated, use their
1740 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1741 and "show auto-load python-scripts" counterparts instead.
1743 ** "dprintf location,format,args..." creates a dynamic printf, which
1744 is basically a breakpoint that does a printf and immediately
1745 resumes your program's execution, so it is like a printf that you
1746 can insert dynamically at runtime instead of at compiletime.
1748 ** "set print symbol"
1750 Controls whether GDB attempts to display the symbol, if any,
1751 corresponding to addresses it prints. This defaults to "on", but
1752 you can set it to "off" to restore GDB's previous behavior.
1754 * Deprecated commands
1756 ** For the Renesas Super-H architecture, the "regs" command has been
1757 deprecated, and "info all-registers" should be used instead.
1761 Renesas RL78 rl78-*-elf
1762 HP OpenVMS ia64 ia64-hp-openvms*
1764 * GDBserver supports evaluation of breakpoint conditions. When
1765 support is advertised by GDBserver, GDB may be told to send the
1766 breakpoint conditions in bytecode form to GDBserver. GDBserver
1767 will only report the breakpoint trigger to GDB when its condition
1772 set mips compression
1773 show mips compression
1774 Select the compressed ISA encoding used in functions that have no symbol
1775 information available. The encoding can be set to either of:
1778 and is updated automatically from ELF file flags if available.
1780 set breakpoint condition-evaluation
1781 show breakpoint condition-evaluation
1782 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1783 GDBserver ("target"). Default option "auto" chooses the most efficient
1785 This option can improve debugger efficiency depending on the speed of the
1789 Disable auto-loading globally.
1792 Show auto-loading setting of all kinds of auto-loaded files.
1794 set auto-load gdb-scripts on|off
1795 show auto-load gdb-scripts
1796 Control auto-loading of GDB canned sequences of commands files.
1798 set auto-load python-scripts on|off
1799 show auto-load python-scripts
1800 Control auto-loading of Python script files.
1802 set auto-load local-gdbinit on|off
1803 show auto-load local-gdbinit
1804 Control loading of init file (.gdbinit) from current directory.
1806 set auto-load libthread-db on|off
1807 show auto-load libthread-db
1808 Control auto-loading of inferior specific thread debugging shared library.
1810 set auto-load scripts-directory <dir1>[:<dir2>...]
1811 show auto-load scripts-directory
1812 Set a list of directories from which to load auto-loaded scripts.
1813 Automatically loaded Python scripts and GDB scripts are located in one
1814 of the directories listed by this option.
1815 The delimiter (':' above) may differ according to the host platform.
1817 set auto-load safe-path <dir1>[:<dir2>...]
1818 show auto-load safe-path
1819 Set a list of directories from which it is safe to auto-load files.
1820 The delimiter (':' above) may differ according to the host platform.
1822 set debug auto-load on|off
1823 show debug auto-load
1824 Control display of debugging info for auto-loading the files above.
1826 set dprintf-style gdb|call|agent
1828 Control the way in which a dynamic printf is performed; "gdb"
1829 requests a GDB printf command, while "call" causes dprintf to call a
1830 function in the inferior. "agent" requests that the target agent
1831 (such as GDBserver) do the printing.
1833 set dprintf-function <expr>
1834 show dprintf-function
1835 set dprintf-channel <expr>
1836 show dprintf-channel
1837 Set the function and optional first argument to the call when using
1838 the "call" style of dynamic printf.
1840 set disconnected-dprintf on|off
1841 show disconnected-dprintf
1842 Control whether agent-style dynamic printfs continue to be in effect
1843 after GDB disconnects.
1845 * New configure options
1847 --with-auto-load-dir
1848 Configure default value for the 'set auto-load scripts-directory'
1849 setting above. It defaults to '$debugdir:$datadir/auto-load',
1850 $debugdir representing global debugging info directories (available
1851 via 'show debug-file-directory') and $datadir representing GDB's data
1852 directory (available via 'show data-directory').
1854 --with-auto-load-safe-path
1855 Configure default value for the 'set auto-load safe-path' setting
1856 above. It defaults to the --with-auto-load-dir setting.
1858 --without-auto-load-safe-path
1859 Set 'set auto-load safe-path' to '/', effectively disabling this
1862 * New remote packets
1864 z0/z1 conditional breakpoints extension
1866 The z0/z1 breakpoint insertion packets have been extended to carry
1867 a list of conditional expressions over to the remote stub depending on the
1868 condition evaluation mode. The use of this extension can be controlled
1869 via the "set remote conditional-breakpoints-packet" command.
1873 Specify the signals which the remote stub may pass to the debugged
1874 program without GDB involvement.
1876 * New command line options
1878 --init-command=FILE, -ix Like --command, -x but execute it
1879 before loading inferior.
1880 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1881 execute it before loading inferior.
1883 *** Changes in GDB 7.4
1885 * GDB now handles ambiguous linespecs more consistently; the existing
1886 FILE:LINE support has been expanded to other types of linespecs. A
1887 breakpoint will now be set on all matching locations in all
1888 inferiors, and locations will be added or removed according to
1891 * GDB now allows you to skip uninteresting functions and files when
1892 stepping with the "skip function" and "skip file" commands.
1894 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1895 and "show remote hardware-watchpoint-length-limit". These allows to
1896 set or show the maximum length limit (in bytes) of a remote
1897 target hardware watchpoint.
1899 This allows e.g. to use "unlimited" hardware watchpoints with the
1900 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1901 watchpoints are slower than real hardware watchpoints but are
1902 significantly faster than gdb software watchpoints.
1906 ** The register_pretty_printer function in module gdb.printing now takes
1907 an optional `replace' argument. If True, the new printer replaces any
1910 ** The "maint set python print-stack on|off" command has been
1911 deprecated and will be deleted in GDB 7.5.
1912 A new command: "set python print-stack none|full|message" has
1913 replaced it. Additionally, the default for "print-stack" is
1914 now "message", which just prints the error message without
1917 ** A prompt substitution hook (prompt_hook) is now available to the
1920 ** A new Python module, gdb.prompt has been added to the GDB Python
1921 modules library. This module provides functionality for
1922 escape sequences in prompts (used by set/show
1923 extended-prompt). These escape sequences are replaced by their
1924 corresponding value.
1926 ** Python commands and convenience-functions located in
1927 'data-directory'/python/gdb/command and
1928 'data-directory'/python/gdb/function are now automatically loaded
1931 ** Blocks now provide four new attributes. global_block and
1932 static_block will return the global and static blocks
1933 respectively. is_static and is_global are boolean attributes
1934 that indicate if the block is one of those two types.
1936 ** Symbols now provide the "type" attribute, the type of the symbol.
1938 ** The "gdb.breakpoint" function has been deprecated in favor of
1941 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1942 of a function. This class is based on the "finish" command
1943 available in the CLI.
1945 ** Type objects for struct and union types now allow access to
1946 the fields using standard Python dictionary (mapping) methods.
1947 For example, "some_type['myfield']" now works, as does
1948 "some_type.items()".
1950 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1953 ** A new function, "deep_items" has been added to the gdb.types
1954 module in the GDB Python modules library. This function returns
1955 an iterator over the fields of a struct or union type. Unlike
1956 the standard Python "iteritems" method, it will recursively traverse
1957 any anonymous fields.
1961 ** "*stopped" events can report several new "reason"s, such as
1964 ** Breakpoint changes are now notified using new async records, like
1965 "=breakpoint-modified".
1967 ** New command -ada-task-info.
1969 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1970 $sdir specifies the default system locations of shared libraries.
1971 $pdir specifies the directory where the libpthread used by the application
1974 GDB no longer looks in $sdir and $pdir after it has searched the directories
1975 mentioned in libthread-db-search-path. If you want to search those
1976 directories, they must be specified in libthread-db-search-path.
1977 The default value of libthread-db-search-path on GNU/Linux and Solaris
1978 systems is now "$sdir:$pdir".
1980 $pdir is not supported by gdbserver, it is currently ignored.
1981 $sdir is supported by gdbserver.
1983 * New configure option --with-iconv-bin.
1984 When using the internationalization support like the one in the GNU C
1985 library, GDB will invoke the "iconv" program to get a list of supported
1986 character sets. If this program lives in a non-standard location, one can
1987 use this option to specify where to find it.
1989 * When natively debugging programs on PowerPC BookE processors running
1990 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1991 watchpoints, which specify a mask in addition to an address to watch.
1992 The mask specifies that some bits of an address (the bits which are
1993 reset in the mask) should be ignored when matching the address accessed
1994 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1995 section in the user manual for more details.
1997 * The new option --once causes GDBserver to stop listening for connections once
1998 the first connection is made. The listening port used by GDBserver will
1999 become available after that.
2001 * New commands "info macros" and "alias" have been added.
2003 * New function parameters suffix @entry specifies value of function parameter
2004 at the time the function got called. Entry values are available only since
2010 "!" is now an alias of the "shell" command.
2011 Note that no space is needed between "!" and SHELL COMMAND.
2015 watch EXPRESSION mask MASK_VALUE
2016 The watch command now supports the mask argument which allows creation
2017 of masked watchpoints, if the current architecture supports this feature.
2019 info auto-load-scripts [REGEXP]
2020 This command was formerly named "maintenance print section-scripts".
2021 It is now generally useful and is no longer a maintenance-only command.
2023 info macro [-all] [--] MACRO
2024 The info macro command has new options `-all' and `--'. The first for
2025 printing all definitions of a macro. The second for explicitly specifying
2026 the end of arguments and the beginning of the macro name in case the macro
2027 name starts with a hyphen.
2029 collect[/s] EXPRESSIONS
2030 The tracepoint collect command now takes an optional modifier "/s"
2031 that directs it to dereference pointer-to-character types and
2032 collect the bytes of memory up to a zero byte. The behavior is
2033 similar to what you see when you use the regular print command on a
2034 string. An optional integer following the "/s" sets a bound on the
2035 number of bytes that will be collected.
2038 The trace start command now interprets any supplied arguments as a
2039 note to be recorded with the trace run, with an effect similar to
2040 setting the variable trace-notes.
2043 The trace stop command now interprets any arguments as a note to be
2044 mentioned along with the tstatus report that the trace was stopped
2045 with a command. The effect is similar to setting the variable
2048 * Tracepoints can now be enabled and disabled at any time after a trace
2049 experiment has been started using the standard "enable" and "disable"
2050 commands. It is now possible to start a trace experiment with no enabled
2051 tracepoints; GDB will display a warning, but will allow the experiment to
2052 begin, assuming that tracepoints will be enabled as needed while the trace
2055 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2056 locations with 4-byte instructions, when they were previously
2057 limited to locations with instructions of 5 bytes or longer.
2061 set debug dwarf2-read
2062 show debug dwarf2-read
2063 Turns on or off display of debugging messages related to reading
2064 DWARF debug info. The default is off.
2066 set debug symtab-create
2067 show debug symtab-create
2068 Turns on or off display of debugging messages related to symbol table
2069 creation. The default is off.
2072 show extended-prompt
2073 Set the GDB prompt, and allow escape sequences to be inserted to
2074 display miscellaneous information (see 'help set extended-prompt'
2075 for the list of sequences). This prompt (and any information
2076 accessed through the escape sequences) is updated every time the
2077 prompt is displayed.
2079 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2080 show print entry-values
2081 Set printing of frame argument values at function entry. In some cases
2082 GDB can determine the value of function argument which was passed by the
2083 function caller, even if the value was modified inside the called function.
2085 set debug entry-values
2086 show debug entry-values
2087 Control display of debugging info for determining frame argument values at
2088 function entry and virtual tail call frames.
2090 set basenames-may-differ
2091 show basenames-may-differ
2092 Set whether a source file may have multiple base names.
2093 (A "base name" is the name of a file with the directory part removed.
2094 Example: The base name of "/home/user/hello.c" is "hello.c".)
2095 If set, GDB will canonicalize file names (e.g., expand symlinks)
2096 before comparing them. Canonicalization is an expensive operation,
2097 but it allows the same file be known by more than one base name.
2098 If not set (the default), all source files are assumed to have just
2099 one base name, and gdb will do file name comparisons more efficiently.
2105 Set a user name and notes for the current and any future trace runs.
2106 This is useful for long-running and/or disconnected traces, to
2107 inform others (or yourself) as to who is running the trace, supply
2108 contact information, or otherwise explain what is going on.
2110 set trace-stop-notes
2111 show trace-stop-notes
2112 Set a note attached to the trace run, that is displayed when the
2113 trace has been stopped by a tstop command. This is useful for
2114 instance as an explanation, if you are stopping a trace run that was
2115 started by someone else.
2117 * New remote packets
2121 Dynamically enable a tracepoint in a started trace experiment.
2125 Dynamically disable a tracepoint in a started trace experiment.
2129 Set the user and notes of the trace run.
2133 Query the current status of a tracepoint.
2137 Query the minimum length of instruction at which a fast tracepoint may
2140 * Dcache size (number of lines) and line-size are now runtime-configurable
2141 via "set dcache line" and "set dcache line-size" commands.
2145 Texas Instruments TMS320C6x tic6x-*-*
2149 Renesas RL78 rl78-*-elf
2151 *** Changes in GDB 7.3.1
2153 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2155 *** Changes in GDB 7.3
2157 * GDB has a new command: "thread find [REGEXP]".
2158 It finds the thread id whose name, target id, or thread extra info
2159 matches the given regular expression.
2161 * The "catch syscall" command now works on mips*-linux* targets.
2163 * The -data-disassemble MI command now supports modes 2 and 3 for
2164 dumping the instruction opcodes.
2166 * New command line options
2168 -data-directory DIR Specify DIR as the "data-directory".
2169 This is mostly for testing purposes.
2171 * The "maint set python auto-load on|off" command has been renamed to
2172 "set auto-load-scripts on|off".
2174 * GDB has a new command: "set directories".
2175 It is like the "dir" command except that it replaces the
2176 source path list instead of augmenting it.
2178 * GDB now understands thread names.
2180 On GNU/Linux, "info threads" will display the thread name as set by
2181 prctl or pthread_setname_np.
2183 There is also a new command, "thread name", which can be used to
2184 assign a name internally for GDB to display.
2187 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2188 has been integrated into GDB.
2192 ** The function gdb.Write now accepts an optional keyword 'stream'.
2193 This keyword, when provided, will direct the output to either
2194 stdout, stderr, or GDB's logging output.
2196 ** Parameters can now be be sub-classed in Python, and in particular
2197 you may implement the get_set_doc and get_show_doc functions.
2198 This improves how Parameter set/show documentation is processed
2199 and allows for more dynamic content.
2201 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2202 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2203 have an is_valid method.
2205 ** Breakpoints can now be sub-classed in Python, and in particular
2206 you may implement a 'stop' function that is executed each time
2207 the inferior reaches that breakpoint.
2209 ** New function gdb.lookup_global_symbol looks up a global symbol.
2211 ** GDB values in Python are now callable if the value represents a
2212 function. For example, if 'some_value' represents a function that
2213 takes two integer parameters and returns a value, you can call
2214 that function like so:
2216 result = some_value (10,20)
2218 ** Module gdb.types has been added.
2219 It contains a collection of utilities for working with gdb.Types objects:
2220 get_basic_type, has_field, make_enum_dict.
2222 ** Module gdb.printing has been added.
2223 It contains utilities for writing and registering pretty-printers.
2224 New classes: PrettyPrinter, SubPrettyPrinter,
2225 RegexpCollectionPrettyPrinter.
2226 New function: register_pretty_printer.
2228 ** New commands "info pretty-printers", "enable pretty-printer" and
2229 "disable pretty-printer" have been added.
2231 ** gdb.parameter("directories") is now available.
2233 ** New function gdb.newest_frame returns the newest frame in the
2236 ** The gdb.InferiorThread class has a new "name" attribute. This
2237 holds the thread's name.
2239 ** Python Support for Inferior events.
2240 Python scripts can add observers to be notified of events
2241 occurring in the process being debugged.
2242 The following events are currently supported:
2243 - gdb.events.cont Continue event.
2244 - gdb.events.exited Inferior exited event.
2245 - gdb.events.stop Signal received, and Breakpoint hit events.
2249 ** GDB now puts template parameters in scope when debugging in an
2250 instantiation. For example, if you have:
2252 template<int X> int func (void) { return X; }
2254 then if you step into func<5>, "print X" will show "5". This
2255 feature requires proper debuginfo support from the compiler; it
2256 was added to GCC 4.5.
2258 ** The motion commands "next", "finish", "until", and "advance" now
2259 work better when exceptions are thrown. In particular, GDB will
2260 no longer lose control of the inferior; instead, the GDB will
2261 stop the inferior at the point at which the exception is caught.
2262 This functionality requires a change in the exception handling
2263 code that was introduced in GCC 4.5.
2265 * GDB now follows GCC's rules on accessing volatile objects when
2266 reading or writing target state during expression evaluation.
2267 One notable difference to prior behavior is that "print x = 0"
2268 no longer generates a read of x; the value of the assignment is
2269 now always taken directly from the value being assigned.
2271 * GDB now has some support for using labels in the program's source in
2272 linespecs. For instance, you can use "advance label" to continue
2273 execution to a label.
2275 * GDB now has support for reading and writing a new .gdb_index
2276 section. This section holds a fast index of DWARF debugging
2277 information and can be used to greatly speed up GDB startup and
2278 operation. See the documentation for `save gdb-index' for details.
2280 * The "watch" command now accepts an optional "-location" argument.
2281 When used, this causes GDB to watch the memory referred to by the
2282 expression. Such a watchpoint is never deleted due to it going out
2285 * GDB now supports thread debugging of core dumps on GNU/Linux.
2287 GDB now activates thread debugging using the libthread_db library
2288 when debugging GNU/Linux core dumps, similarly to when debugging
2289 live processes. As a result, when debugging a core dump file, GDB
2290 is now able to display pthread_t ids of threads. For example, "info
2291 threads" shows the same output as when debugging the process when it
2292 was live. In earlier releases, you'd see something like this:
2295 * 1 LWP 6780 main () at main.c:10
2297 While now you see this:
2300 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2302 It is also now possible to inspect TLS variables when debugging core
2305 When debugging a core dump generated on a machine other than the one
2306 used to run GDB, you may need to point GDB at the correct
2307 libthread_db library with the "set libthread-db-search-path"
2308 command. See the user manual for more details on this command.
2310 * When natively debugging programs on PowerPC BookE processors running
2311 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2312 which stop execution of the inferior whenever it executes an instruction
2313 at any address within the specified range. See the "PowerPC Embedded"
2314 section in the user manual for more details.
2316 * New features in the GDB remote stub, GDBserver
2318 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2319 and i686 LynxOS (version 5.x).
2321 ** GDBserver is now supported on Blackfin Linux.
2323 * New native configurations
2325 ia64 HP-UX ia64-*-hpux*
2329 Analog Devices, Inc. Blackfin Processor bfin-*
2331 * Ada task switching is now supported on sparc-elf targets when
2332 debugging a program using the Ravenscar Profile. For more information,
2333 see the "Tasking Support when using the Ravenscar Profile" section
2334 in the GDB user manual.
2336 * Guile support was removed.
2338 * New features in the GNU simulator
2340 ** The --map-info flag lists all known core mappings.
2342 ** CFI flashes may be simulated via the "cfi" device.
2344 *** Changes in GDB 7.2
2346 * Shared library support for remote targets by default
2348 When GDB is configured for a generic, non-OS specific target, like
2349 for example, --target=arm-eabi or one of the many *-*-elf targets,
2350 GDB now queries remote stubs for loaded shared libraries using the
2351 `qXfer:libraries:read' packet. Previously, shared library support
2352 was always disabled for such configurations.
2356 ** Argument Dependent Lookup (ADL)
2358 In C++ ADL lookup directs function search to the namespaces of its
2359 arguments even if the namespace has not been imported.
2369 Here the compiler will search for `foo' in the namespace of 'b'
2370 and find A::foo. GDB now supports this. This construct is commonly
2371 used in the Standard Template Library for operators.
2373 ** Improved User Defined Operator Support
2375 In addition to member operators, GDB now supports lookup of operators
2376 defined in a namespace and imported with a `using' directive, operators
2377 defined in the global scope, operators imported implicitly from an
2378 anonymous namespace, and the ADL operators mentioned in the previous
2380 GDB now also supports proper overload resolution for all the previously
2381 mentioned flavors of operators.
2383 ** static const class members
2385 Printing of static const class members that are initialized in the
2386 class definition has been fixed.
2388 * Windows Thread Information Block access.
2390 On Windows targets, GDB now supports displaying the Windows Thread
2391 Information Block (TIB) structure. This structure is visible either
2392 by using the new command `info w32 thread-information-block' or, by
2393 dereferencing the new convenience variable named `$_tlb', a
2394 thread-specific pointer to the TIB. This feature is also supported
2395 when remote debugging using GDBserver.
2397 * Static tracepoints
2399 Static tracepoints are calls in the user program into a tracing
2400 library. One such library is a port of the LTTng kernel tracer to
2401 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2402 When debugging with GDBserver, GDB now supports combining the GDB
2403 tracepoint machinery with such libraries. For example: the user can
2404 use GDB to probe a static tracepoint marker (a call from the user
2405 program into the tracing library) with the new "strace" command (see
2406 "New commands" below). This creates a "static tracepoint" in the
2407 breakpoint list, that can be manipulated with the same feature set
2408 as fast and regular tracepoints. E.g., collect registers, local and
2409 global variables, collect trace state variables, and define
2410 tracepoint conditions. In addition, the user can collect extra
2411 static tracepoint marker specific data, by collecting the new
2412 $_sdata internal variable. When analyzing the trace buffer, you can
2413 inspect $_sdata like any other variable available to GDB. For more
2414 information, see the "Tracepoints" chapter in GDB user manual. New
2415 remote packets have been defined to support static tracepoints, see
2416 the "New remote packets" section below.
2418 * Better reconstruction of tracepoints after disconnected tracing
2420 GDB will attempt to download the original source form of tracepoint
2421 definitions when starting a trace run, and then will upload these
2422 upon reconnection to the target, resulting in a more accurate
2423 reconstruction of the tracepoints that are in use on the target.
2427 You can now exercise direct control over the ways that GDB can
2428 affect your program. For instance, you can disallow the setting of
2429 breakpoints, so that the program can run continuously (assuming
2430 non-stop mode). In addition, the "observer" variable is available
2431 to switch all of the different controls; in observer mode, GDB
2432 cannot affect the target's behavior at all, which is useful for
2433 tasks like diagnosing live systems in the field.
2435 * The new convenience variable $_thread holds the number of the
2438 * New remote packets
2442 Return the address of the Windows Thread Information Block of a given thread.
2446 In response to several of the tracepoint packets, the target may now
2447 also respond with a number of intermediate `qRelocInsn' request
2448 packets before the final result packet, to have GDB handle
2449 relocating an instruction to execute at a different address. This
2450 is particularly useful for stubs that support fast tracepoints. GDB
2451 reports support for this feature in the qSupported packet.
2455 List static tracepoint markers in the target program.
2459 List static tracepoint markers at a given address in the target
2462 qXfer:statictrace:read
2464 Read the static trace data collected (by a `collect $_sdata'
2465 tracepoint action). The remote stub reports support for this packet
2466 to gdb's qSupported query.
2470 Send the current settings of GDB's permission flags.
2474 Send part of the source (textual) form of a tracepoint definition,
2475 which includes location, conditional, and action list.
2477 * The source command now accepts a -s option to force searching for the
2478 script in the source search path even if the script name specifies
2481 * New features in the GDB remote stub, GDBserver
2483 - GDBserver now support tracepoints (including fast tracepoints, and
2484 static tracepoints). The feature is currently supported by the
2485 i386-linux and amd64-linux builds. See the "Tracepoints support
2486 in gdbserver" section in the manual for more information.
2488 GDBserver JIT compiles the tracepoint's conditional agent
2489 expression bytecode into native code whenever possible for low
2490 overhead dynamic tracepoints conditionals. For such tracepoints,
2491 an expression that examines program state is evaluated when the
2492 tracepoint is reached, in order to determine whether to capture
2493 trace data. If the condition is simple and false, processing the
2494 tracepoint finishes very quickly and no data is gathered.
2496 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2497 for static tracepoints support.
2499 - GDBserver now supports x86_64 Windows 64-bit debugging.
2501 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2502 it understands register description.
2504 * The --batch flag now disables pagination and queries.
2506 * X86 general purpose registers
2508 GDB now supports reading/writing byte, word and double-word x86
2509 general purpose registers directly. This means you can use, say,
2510 $ah or $ax to refer, respectively, to the byte register AH and
2511 16-bit word register AX that are actually portions of the 32-bit
2512 register EAX or 64-bit register RAX.
2514 * The `commands' command now accepts a range of breakpoints to modify.
2515 A plain `commands' following a command that creates multiple
2516 breakpoints affects all the breakpoints set by that command. This
2517 applies to breakpoints set by `rbreak', and also applies when a
2518 single `break' command creates multiple breakpoints (e.g.,
2519 breakpoints on overloaded c++ functions).
2521 * The `rbreak' command now accepts a filename specification as part of
2522 its argument, limiting the functions selected by the regex to those
2523 in the specified file.
2525 * Support for remote debugging Windows and SymbianOS shared libraries
2526 from Unix hosts has been improved. Non Windows GDB builds now can
2527 understand target reported file names that follow MS-DOS based file
2528 system semantics, such as file names that include drive letters and
2529 use the backslash character as directory separator. This makes it
2530 possible to transparently use the "set sysroot" and "set
2531 solib-search-path" on Unix hosts to point as host copies of the
2532 target's shared libraries. See the new command "set
2533 target-file-system-kind" described below, and the "Commands to
2534 specify files" section in the user manual for more information.
2538 eval template, expressions...
2539 Convert the values of one or more expressions under the control
2540 of the string template to a command line, and call it.
2542 set target-file-system-kind unix|dos-based|auto
2543 show target-file-system-kind
2544 Set or show the assumed file system kind for target reported file
2547 save breakpoints <filename>
2548 Save all current breakpoint definitions to a file suitable for use
2549 in a later debugging session. To read the saved breakpoint
2550 definitions, use the `source' command.
2552 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2555 info static-tracepoint-markers
2556 Display information about static tracepoint markers in the target.
2558 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2559 Define a static tracepoint by probing a marker at the given
2560 function, line, address, or marker ID.
2564 Enable and disable observer mode.
2566 set may-write-registers on|off
2567 set may-write-memory on|off
2568 set may-insert-breakpoints on|off
2569 set may-insert-tracepoints on|off
2570 set may-insert-fast-tracepoints on|off
2571 set may-interrupt on|off
2572 Set individual permissions for GDB effects on the target. Note that
2573 some of these settings can have undesirable or surprising
2574 consequences, particularly when changed in the middle of a session.
2575 For instance, disabling the writing of memory can prevent
2576 breakpoints from being inserted, cause single-stepping to fail, or
2577 even crash your program, if you disable after breakpoints have been
2578 inserted. However, GDB should not crash.
2580 set record memory-query on|off
2581 show record memory-query
2582 Control whether to stop the inferior if memory changes caused
2583 by an instruction cannot be recorded.
2588 The disassemble command now supports "start,+length" form of two arguments.
2592 ** GDB now provides a new directory location, called the python directory,
2593 where Python scripts written for GDB can be installed. The location
2594 of that directory is <data-directory>/python, where <data-directory>
2595 is the GDB data directory. For more details, see section `Scripting
2596 GDB using Python' in the manual.
2598 ** The GDB Python API now has access to breakpoints, symbols, symbol
2599 tables, program spaces, inferiors, threads and frame's code blocks.
2600 Additionally, GDB Parameters can now be created from the API, and
2601 manipulated via set/show in the CLI.
2603 ** New functions gdb.target_charset, gdb.target_wide_charset,
2604 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2606 ** New exception gdb.GdbError.
2608 ** Pretty-printers are now also looked up in the current program space.
2610 ** Pretty-printers can now be individually enabled and disabled.
2612 ** GDB now looks for names of Python scripts to auto-load in a
2613 special section named `.debug_gdb_scripts', in addition to looking
2614 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2616 * Tracepoint actions were unified with breakpoint commands. In particular,
2617 there are no longer differences in "info break" output for breakpoints and
2618 tracepoints and the "commands" command can be used for both tracepoints and
2619 regular breakpoints.
2623 ARM Symbian arm*-*-symbianelf*
2625 * D language support.
2626 GDB now supports debugging programs written in the D programming
2629 * GDB now supports the extended ptrace interface for PowerPC which is
2630 available since Linux kernel version 2.6.34. This automatically enables
2631 any hardware breakpoints and additional hardware watchpoints available in
2632 the processor. The old ptrace interface exposes just one hardware
2633 watchpoint and no hardware breakpoints.
2635 * GDB is now able to use the Data Value Compare (DVC) register available on
2636 embedded PowerPC processors to implement in hardware simple watchpoint
2637 conditions of the form:
2639 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2641 This works in native GDB running on Linux kernels with the extended ptrace
2642 interface mentioned above.
2644 *** Changes in GDB 7.1
2648 ** Namespace Support
2650 GDB now supports importing of namespaces in C++. This enables the
2651 user to inspect variables from imported namespaces. Support for
2652 namepace aliasing has also been added. So, if a namespace is
2653 aliased in the current scope (e.g. namepace C=A; ) the user can
2654 print variables using the alias (e.g. (gdb) print C::x).
2658 All known bugs relating to the printing of virtual base class were
2659 fixed. It is now possible to call overloaded static methods using a
2664 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2665 and reinterpret_cast<> are now handled by the C++ expression parser.
2669 Xilinx MicroBlaze microblaze-*-*
2674 Xilinx MicroBlaze microblaze
2677 * Multi-program debugging.
2679 GDB now has support for multi-program (a.k.a. multi-executable or
2680 multi-exec) debugging. This allows for debugging multiple inferiors
2681 simultaneously each running a different program under the same GDB
2682 session. See "Debugging Multiple Inferiors and Programs" in the
2683 manual for more information. This implied some user visible changes
2684 in the multi-inferior support. For example, "info inferiors" now
2685 lists inferiors that are not running yet or that have exited
2686 already. See also "New commands" and "New options" below.
2688 * New tracing features
2690 GDB's tracepoint facility now includes several new features:
2692 ** Trace state variables
2694 GDB tracepoints now include support for trace state variables, which
2695 are variables managed by the target agent during a tracing
2696 experiment. They are useful for tracepoints that trigger each
2697 other, so for instance one tracepoint can count hits in a variable,
2698 and then a second tracepoint has a condition that is true when the
2699 count reaches a particular value. Trace state variables share the
2700 $-syntax of GDB convenience variables, and can appear in both
2701 tracepoint actions and condition expressions. Use the "tvariable"
2702 command to create, and "info tvariables" to view; see "Trace State
2703 Variables" in the manual for more detail.
2707 GDB now includes an option for defining fast tracepoints, which
2708 targets may implement more efficiently, such as by installing a jump
2709 into the target agent rather than a trap instruction. The resulting
2710 speedup can be by two orders of magnitude or more, although the
2711 tradeoff is that some program locations on some target architectures
2712 might not allow fast tracepoint installation, for instance if the
2713 instruction to be replaced is shorter than the jump. To request a
2714 fast tracepoint, use the "ftrace" command, with syntax identical to
2715 the regular trace command.
2717 ** Disconnected tracing
2719 It is now possible to detach GDB from the target while it is running
2720 a trace experiment, then reconnect later to see how the experiment
2721 is going. In addition, a new variable disconnected-tracing lets you
2722 tell the target agent whether to continue running a trace if the
2723 connection is lost unexpectedly.
2727 GDB now has the ability to save the trace buffer into a file, and
2728 then use that file as a target, similarly to you can do with
2729 corefiles. You can select trace frames, print data that was
2730 collected in them, and use tstatus to display the state of the
2731 tracing run at the moment that it was saved. To create a trace
2732 file, use "tsave <filename>", and to use it, do "target tfile
2735 ** Circular trace buffer
2737 You can ask the target agent to handle the trace buffer as a
2738 circular buffer, discarding the oldest trace frames to make room for
2739 newer ones, by setting circular-trace-buffer to on. This feature may
2740 not be available for all target agents.
2745 The disassemble command, when invoked with two arguments, now requires
2746 the arguments to be comma-separated.
2749 The info variables command now displays variable definitions. Files
2750 which only declare a variable are not shown.
2753 The source command is now capable of sourcing Python scripts.
2754 This feature is dependent on the debugger being build with Python
2757 Related to this enhancement is also the introduction of a new command
2758 "set script-extension" (see below).
2760 * New commands (for set/show, see "New options" below)
2762 record save [<FILENAME>]
2763 Save a file (in core file format) containing the process record
2764 execution log for replay debugging at a later time.
2766 record restore <FILENAME>
2767 Restore the process record execution log that was saved at an
2768 earlier time, for replay debugging.
2770 add-inferior [-copies <N>] [-exec <FILENAME>]
2773 clone-inferior [-copies <N>] [ID]
2774 Make a new inferior ready to execute the same program another
2775 inferior has loaded.
2780 maint info program-spaces
2781 List the program spaces loaded into GDB.
2783 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2784 show remote interrupt-sequence
2785 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2786 as the sequence to the remote target in order to interrupt the execution.
2787 Ctrl-C is a default. Some system prefers BREAK which is high level of
2788 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2789 Magic SysRq g. It is BREAK signal and character 'g'.
2791 set remote interrupt-on-connect [on | off]
2792 show remote interrupt-on-connect
2793 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2794 remote target when gdb connects to it. This is needed when you debug
2797 set remotebreak [on | off]
2799 Deprecated. Use "set/show remote interrupt-sequence" instead.
2801 tvariable $NAME [ = EXP ]
2802 Create or modify a trace state variable.
2805 List trace state variables and their values.
2807 delete tvariable $NAME ...
2808 Delete one or more trace state variables.
2811 Evaluate the given expressions without collecting anything into the
2812 trace buffer. (Valid in tracepoint actions only.)
2814 ftrace FN / FILE:LINE / *ADDR
2815 Define a fast tracepoint at the given function, line, or address.
2817 * New expression syntax
2819 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2820 GDB now parses 0b101010 identically with 42.
2824 set follow-exec-mode new|same
2825 show follow-exec-mode
2826 Control whether GDB reuses the same inferior across an exec call or
2827 creates a new one. This is useful to be able to restart the old
2828 executable after the inferior having done an exec call.
2830 set default-collect EXPR, ...
2831 show default-collect
2832 Define a list of expressions to be collected at each tracepoint.
2833 This is a useful way to ensure essential items are not overlooked,
2834 such as registers or a critical global variable.
2836 set disconnected-tracing
2837 show disconnected-tracing
2838 If set to 1, the target is instructed to continue tracing if it
2839 loses its connection to GDB. If 0, the target is to stop tracing
2842 set circular-trace-buffer
2843 show circular-trace-buffer
2844 If set to on, the target is instructed to use a circular trace buffer
2845 and discard the oldest trace frames instead of stopping the trace due
2846 to a full trace buffer. If set to off, the trace stops when the buffer
2847 fills up. Some targets may not support this.
2849 set script-extension off|soft|strict
2850 show script-extension
2851 If set to "off", the debugger does not perform any script language
2852 recognition, and all sourced files are assumed to be GDB scripts.
2853 If set to "soft" (the default), files are sourced according to
2854 filename extension, falling back to GDB scripts if the first
2856 If set to "strict", files are sourced according to filename extension.
2858 set ada trust-PAD-over-XVS on|off
2859 show ada trust-PAD-over-XVS
2860 If off, activate a workaround against a bug in the debugging information
2861 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2862 the GCC sources for more information about the GNAT encoding and
2863 PAD types in particular). It is always safe to set this option to
2864 off, but this introduces a slight performance penalty. The default
2867 * Python API Improvements
2869 ** GDB provides the new class gdb.LazyString. This is useful in
2870 some pretty-printing cases. The new method gdb.Value.lazy_string
2871 provides a simple way to create objects of this type.
2873 ** The fields returned by gdb.Type.fields now have an
2874 `is_base_class' attribute.
2876 ** The new method gdb.Type.range returns the range of an array type.
2878 ** The new method gdb.parse_and_eval can be used to parse and
2879 evaluate an expression.
2881 * New remote packets
2884 Define a trace state variable.
2887 Get the current value of a trace state variable.
2890 Set desired tracing behavior upon disconnection.
2893 Set the trace buffer to be linear or circular.
2896 Get data about the tracepoints currently in use.
2900 Process record now works correctly with hardware watchpoints.
2902 Multiple bug fixes have been made to the mips-irix port, making it
2903 much more reliable. In particular:
2904 - Debugging threaded applications is now possible again. Previously,
2905 GDB would hang while starting the program, or while waiting for
2906 the program to stop at a breakpoint.
2907 - Attaching to a running process no longer hangs.
2908 - An error occurring while loading a core file has been fixed.
2909 - Changing the value of the PC register now works again. This fixes
2910 problems observed when using the "jump" command, or when calling
2911 a function from GDB, or even when assigning a new value to $pc.
2912 - With the "finish" and "return" commands, the return value for functions
2913 returning a small array is now correctly printed.
2914 - It is now possible to break on shared library code which gets executed
2915 during a shared library init phase (code executed while executing
2916 their .init section). Previously, the breakpoint would have no effect.
2917 - GDB is now able to backtrace through the signal handler for
2918 non-threaded programs.
2920 PIE (Position Independent Executable) programs debugging is now supported.
2921 This includes debugging execution of PIC (Position Independent Code) shared
2922 libraries although for that, it should be possible to run such libraries as an
2925 *** Changes in GDB 7.0
2927 * GDB now has an interface for JIT compilation. Applications that
2928 dynamically generate code can create symbol files in memory and register
2929 them with GDB. For users, the feature should work transparently, and
2930 for JIT developers, the interface is documented in the GDB manual in the
2931 "JIT Compilation Interface" chapter.
2933 * Tracepoints may now be conditional. The syntax is as for
2934 breakpoints; either an "if" clause appended to the "trace" command,
2935 or the "condition" command is available. GDB sends the condition to
2936 the target for evaluation using the same bytecode format as is used
2937 for tracepoint actions.
2939 * The disassemble command now supports: an optional /r modifier, print the
2940 raw instructions in hex as well as in symbolic form, and an optional /m
2941 modifier to print mixed source+assembly.
2943 * Process record and replay
2945 In a architecture environment that supports ``process record and
2946 replay'', ``process record and replay'' target can record a log of
2947 the process execution, and replay it with both forward and reverse
2950 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2951 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2952 set execution-direction {forward|reverse}, for targets that support
2955 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2956 feature is available with a native GDB running on kernel version
2959 * GDB now has support for multi-byte and wide character sets on the
2960 target. Strings whose character type is wchar_t, char16_t, or
2961 char32_t are now correctly printed. GDB supports wide- and unicode-
2962 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2963 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2964 `printf'. This feature requires iconv to work properly; if your
2965 system does not have a working iconv, GDB can use GNU libiconv. See
2966 the installation instructions for more information.
2968 * GDB now supports automatic retrieval of shared library files from
2969 remote targets. To use this feature, specify a system root that begins
2970 with the `remote:' prefix, either via the `set sysroot' command or via
2971 the `--with-sysroot' configure-time option.
2973 * "info sharedlibrary" now takes an optional regex of libraries to show,
2974 and it now reports if a shared library has no debugging information.
2976 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2977 now complete on file names.
2979 * When completing in expressions, gdb will attempt to limit
2980 completions to allowable structure or union fields, where appropriate.
2981 For instance, consider:
2983 # struct example { int f1; double f2; };
2984 # struct example variable;
2987 If the user types TAB at the end of this command line, the available
2988 completions will be "f1" and "f2".
2990 * Inlined functions are now supported. They show up in backtraces, and
2991 the "step", "next", and "finish" commands handle them automatically.
2993 * GDB now supports the token-splicing (##) and stringification (#)
2994 operators when expanding macros. It also supports variable-arity
2997 * GDB now supports inspecting extra signal information, exported by
2998 the new $_siginfo convenience variable. The feature is currently
2999 implemented on linux ARM, i386 and amd64.
3001 * GDB can now display the VFP floating point registers and NEON vector
3002 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3003 can provide these registers (requires Linux 2.6.30 or later). Remote
3004 and simulator targets may also provide them.
3006 * New remote packets
3009 Search memory for a sequence of bytes.
3012 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3013 operation over reliable transport links. Use of this packet is
3014 controlled by the `set remote noack-packet' command.
3017 Kill the process with the specified process ID. Use this in preference
3018 to `k' when multiprocess protocol extensions are supported.
3021 Obtains additional operating system information
3025 Read or write additional signal information.
3027 * Removed remote protocol undocumented extension
3029 An undocumented extension to the remote protocol's `S' stop reply
3030 packet that permited the stub to pass a process id was removed.
3031 Remote servers should use the `T' stop reply packet instead.
3033 * GDB now supports multiple function calling conventions according to the
3034 DWARF-2 DW_AT_calling_convention function attribute.
3036 * The SH target utilizes the aforementioned change to distinguish between gcc
3037 and Renesas calling convention. It also adds the new CLI commands
3038 `set/show sh calling-convention'.
3040 * GDB can now read compressed debug sections, as produced by GNU gold
3041 with the --compress-debug-sections=zlib flag.
3043 * 64-bit core files are now supported on AIX.
3045 * Thread switching is now supported on Tru64.
3047 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3048 which will be allocated using malloc later in program execution.
3050 * The qXfer:libraries:read remote procotol packet now allows passing a
3051 list of section offsets.
3053 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3054 conditions handling signals delivered during attach or thread creation
3055 have also been fixed.
3057 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3058 From the user's standpoint, all unqualified instances of True and False
3059 are treated as the standard definitions, regardless of context.
3061 * GDB now parses C++ symbol and type names more flexibly. For
3064 template<typename T> class C { };
3067 GDB will now correctly handle all of:
3069 ptype C<char const *>
3070 ptype C<char const*>
3071 ptype C<const char *>
3072 ptype C<const char*>
3074 * New features in the GDB remote stub, gdbserver
3076 - The "--wrapper" command-line argument tells gdbserver to use a
3077 wrapper program to launch programs for debugging.
3079 - On PowerPC and S/390 targets, it is now possible to use a single
3080 gdbserver executable to debug both 32-bit and 64-bit programs.
3081 (This requires gdbserver itself to be built as a 64-bit executable.)
3083 - gdbserver uses the new noack protocol mode for TCP connections to
3084 reduce communications latency, if also supported and enabled in GDB.
3086 - Support for the sparc64-linux-gnu target is now included in
3089 - The amd64-linux build of gdbserver now supports debugging both
3090 32-bit and 64-bit programs.
3092 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3093 now support hardware watchpoints, and will use them automatically
3098 GDB now has support for scripting using Python. Whether this is
3099 available is determined at configure time.
3101 New GDB commands can now be written in Python.
3103 * Ada tasking support
3105 Ada tasks can now be inspected in GDB. The following commands have
3109 Print the list of Ada tasks.
3111 Print detailed information about task number N.
3113 Print the task number of the current task.
3115 Switch the context of debugging to task number N.
3117 * Support for user-defined prefixed commands. The "define" command can
3118 add new commands to existing prefixes, e.g. "target".
3120 * Multi-inferior, multi-process debugging.
3122 GDB now has generalized support for multi-inferior debugging. See
3123 "Debugging Multiple Inferiors" in the manual for more information.
3124 Although availability still depends on target support, the command
3125 set is more uniform now. The GNU/Linux specific multi-forks support
3126 has been migrated to this new framework. This implied some user
3127 visible changes; see "New commands" and also "Removed commands"
3130 * Target descriptions can now describe the target OS ABI. See the
3131 "Target Description Format" section in the user manual for more
3134 * Target descriptions can now describe "compatible" architectures
3135 to indicate that the target can execute applications for a different
3136 architecture in addition to those for the main target architecture.
3137 See the "Target Description Format" section in the user manual for
3140 * Multi-architecture debugging.
3142 GDB now includes general supports for debugging applications on
3143 hybrid systems that use more than one single processor architecture
3144 at the same time. Each such hybrid architecture still requires
3145 specific support to be added. The only hybrid architecture supported
3146 in this version of GDB is the Cell Broadband Engine.
3148 * GDB now supports integrated debugging of Cell/B.E. applications that
3149 use both the PPU and SPU architectures. To enable support for hybrid
3150 Cell/B.E. debugging, you need to configure GDB to support both the
3151 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3152 --enable-targets configure option.
3154 * Non-stop mode debugging.
3156 For some targets, GDB now supports an optional mode of operation in
3157 which you can examine stopped threads while other threads continue
3158 to execute freely. This is referred to as non-stop mode, with the
3159 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3160 section in the user manual for more information.
3162 To be able to support remote non-stop debugging, a remote stub needs
3163 to implement the non-stop mode remote protocol extensions, as
3164 described in the "Remote Non-Stop" section of the user manual. The
3165 GDB remote stub, gdbserver, has been adjusted to support these
3166 extensions on linux targets.
3168 * New commands (for set/show, see "New options" below)
3170 catch syscall [NAME(S) | NUMBER(S)]
3171 Catch system calls. Arguments, which should be names of system
3172 calls or their numbers, mean catch only those syscalls. Without
3173 arguments, every syscall will be caught. When the inferior issues
3174 any of the specified syscalls, GDB will stop and announce the system
3175 call, both when it is called and when its call returns. This
3176 feature is currently available with a native GDB running on the
3177 Linux Kernel, under the following architectures: x86, x86_64,
3178 PowerPC and PowerPC64.
3180 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3182 Search memory for a sequence of bytes.
3184 maint set python print-stack
3185 maint show python print-stack
3186 Show a stack trace when an error is encountered in a Python script.
3189 Invoke CODE by passing it to the Python interpreter.
3194 These allow macros to be defined, undefined, and listed
3198 Show operating system information about processes.
3201 List the inferiors currently under GDB's control.
3204 Switch focus to inferior number NUM.
3207 Detach from inferior number NUM.
3210 Kill inferior number NUM.
3214 set spu stop-on-load
3215 show spu stop-on-load
3216 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3218 set spu auto-flush-cache
3219 show spu auto-flush-cache
3220 Control whether to automatically flush the software-managed cache
3221 during Cell/B.E. debugging.
3223 set sh calling-convention
3224 show sh calling-convention
3225 Control the calling convention used when calling SH target functions.
3228 show debug timestamp
3229 Control display of timestamps with GDB debugging output.
3231 set disassemble-next-line
3232 show disassemble-next-line
3233 Control display of disassembled source lines or instructions when
3236 set remote noack-packet
3237 show remote noack-packet
3238 Set/show the use of remote protocol QStartNoAckMode packet. See above
3239 under "New remote packets."
3241 set remote query-attached-packet
3242 show remote query-attached-packet
3243 Control use of remote protocol `qAttached' (query-attached) packet.
3245 set remote read-siginfo-object
3246 show remote read-siginfo-object
3247 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3250 set remote write-siginfo-object
3251 show remote write-siginfo-object
3252 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3255 set remote reverse-continue
3256 show remote reverse-continue
3257 Control use of remote protocol 'bc' (reverse-continue) packet.
3259 set remote reverse-step
3260 show remote reverse-step
3261 Control use of remote protocol 'bs' (reverse-step) packet.
3263 set displaced-stepping
3264 show displaced-stepping
3265 Control displaced stepping mode. Displaced stepping is a way to
3266 single-step over breakpoints without removing them from the debuggee.
3267 Also known as "out-of-line single-stepping".
3270 show debug displaced
3271 Control display of debugging info for displaced stepping.
3273 maint set internal-error
3274 maint show internal-error
3275 Control what GDB does when an internal error is detected.
3277 maint set internal-warning
3278 maint show internal-warning
3279 Control what GDB does when an internal warning is detected.
3284 Use a wrapper program to launch programs for debugging.
3286 set multiple-symbols (all|ask|cancel)
3287 show multiple-symbols
3288 The value of this variable can be changed to adjust the debugger behavior
3289 when an expression or a breakpoint location contains an ambiguous symbol
3290 name (an overloaded function name, for instance).
3292 set breakpoint always-inserted
3293 show breakpoint always-inserted
3294 Keep breakpoints always inserted in the target, as opposed to inserting
3295 them when resuming the target, and removing them when the target stops.
3296 This option can improve debugger performance on slow remote targets.
3298 set arm fallback-mode (arm|thumb|auto)
3299 show arm fallback-mode
3300 set arm force-mode (arm|thumb|auto)
3302 These commands control how ARM GDB determines whether instructions
3303 are ARM or Thumb. The default for both settings is auto, which uses
3304 the current CPSR value for instructions without symbols; previous
3305 versions of GDB behaved as if "set arm fallback-mode arm".
3307 set disable-randomization
3308 show disable-randomization
3309 Standalone programs run with the virtual address space randomization enabled
3310 by default on some platforms. This option keeps the addresses stable across
3311 multiple debugging sessions.
3315 Control whether other threads are stopped or not when some thread hits
3320 Requests that asynchronous execution is enabled in the target, if available.
3321 In this case, it's possible to resume target in the background, and interact
3322 with GDB while the target is running. "show target-async" displays the
3323 current state of asynchronous execution of the target.
3325 set target-wide-charset
3326 show target-wide-charset
3327 The target-wide-charset is the name of the character set that GDB
3328 uses when printing characters whose type is wchar_t.
3330 set tcp auto-retry (on|off)
3332 set tcp connect-timeout
3333 show tcp connect-timeout
3334 These commands allow GDB to retry failed TCP connections to a remote stub
3335 with a specified timeout period; this is useful if the stub is launched
3336 in parallel with GDB but may not be ready to accept connections immediately.
3338 set libthread-db-search-path
3339 show libthread-db-search-path
3340 Control list of directories which GDB will search for appropriate
3343 set schedule-multiple (on|off)
3344 show schedule-multiple
3345 Allow GDB to resume all threads of all processes or only threads of
3346 the current process.
3350 Use more aggressive caching for accesses to the stack. This improves
3351 performance of remote debugging (particularly backtraces) without
3352 affecting correctness.
3354 set interactive-mode (on|off|auto)
3355 show interactive-mode
3356 Control whether GDB runs in interactive mode (on) or not (off).
3357 When in interactive mode, GDB waits for the user to answer all
3358 queries. Otherwise, GDB does not wait and assumes the default
3359 answer. When set to auto (the default), GDB determines which
3360 mode to use based on the stdin settings.
3365 For program forks, this is replaced by the new more generic `info
3366 inferiors' command. To list checkpoints, you can still use the
3367 `info checkpoints' command, which was an alias for the `info forks'
3371 Replaced by the new `inferior' command. To switch between
3372 checkpoints, you can still use the `restart' command, which was an
3373 alias for the `fork' command.
3376 This is removed, since some targets don't have a notion of
3377 processes. To switch between processes, you can still use the
3378 `inferior' command using GDB's own inferior number.
3381 For program forks, this is replaced by the new more generic `kill
3382 inferior' command. To delete a checkpoint, you can still use the
3383 `delete checkpoint' command, which was an alias for the `delete
3387 For program forks, this is replaced by the new more generic `detach
3388 inferior' command. To detach a checkpoint, you can still use the
3389 `detach checkpoint' command, which was an alias for the `detach
3392 * New native configurations
3394 x86/x86_64 Darwin i[34567]86-*-darwin*
3396 x86_64 MinGW x86_64-*-mingw*
3400 Lattice Mico32 lm32-*
3401 x86 DICOS i[34567]86-*-dicos*
3402 x86_64 DICOS x86_64-*-dicos*
3405 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3406 (mingw32ce) debugging.
3412 These commands were actually not implemented on any target.
3414 *** Changes in GDB 6.8
3416 * New native configurations
3418 NetBSD/hppa hppa*-*netbsd*
3419 Xtensa GNU/Linux xtensa*-*-linux*
3423 NetBSD/hppa hppa*-*-netbsd*
3424 Xtensa GNU/Lunux xtensa*-*-linux*
3426 * Change in command line behavior -- corefiles vs. process ids.
3428 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3429 attaching to process NUMBER fails, GDB no longer attempts to open a
3430 core file named NUMBER. Attaching to a program using the -c option
3431 is no longer supported. Instead, use the '-p' or '--pid' options.
3433 * GDB can now be built as a native debugger for debugging Windows x86
3434 (mingw32) Portable Executable (PE) programs.
3436 * Pending breakpoints no longer change their number when their address
3439 * GDB now supports breakpoints with multiple locations,
3440 including breakpoints on C++ constructors, inside C++ templates,
3441 and in inlined functions.
3443 * GDB's ability to debug optimized code has been improved. GDB more
3444 accurately identifies function bodies and lexical blocks that occupy
3445 more than one contiguous range of addresses.
3447 * Target descriptions can now describe registers for PowerPC.
3449 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3450 registers on PowerPC targets.
3452 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3453 targets even when the libthread_db library is not available.
3455 * The GDB remote stub, gdbserver, now supports the new file transfer
3456 commands (remote put, remote get, and remote delete).
3458 * The GDB remote stub, gdbserver, now supports run and attach in
3459 extended-remote mode.
3461 * hppa*64*-*-hpux11* target broken
3462 The debugger is unable to start a program and fails with the following
3463 error: "Error trying to get information about dynamic linker".
3464 The gdb-6.7 release is also affected.
3466 * GDB now supports the --enable-targets= configure option to allow
3467 building a single GDB executable that supports multiple remote
3468 target architectures.
3470 * GDB now supports debugging C and C++ programs which use the
3471 Decimal Floating Point extension. In addition, the PowerPC target
3472 now has a set of pseudo-registers to inspect decimal float values
3473 stored in two consecutive float registers.
3475 * The -break-insert MI command can optionally create pending
3478 * Improved support for debugging Ada
3479 Many improvements to the Ada language support have been made. These
3481 - Better support for Ada2005 interface types
3482 - Improved handling of arrays and slices in general
3483 - Better support for Taft-amendment types
3484 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3486 - Improved command completion in Ada
3489 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3494 set print frame-arguments (all|scalars|none)
3495 show print frame-arguments
3496 The value of this variable can be changed to control which argument
3497 values should be printed by the debugger when displaying a frame.
3502 Transfer files to and from a remote target, and delete remote files.
3509 Transfer files to and from a remote target, and delete remote files.
3511 * New remote packets
3518 Open, close, read, write, and delete files on the remote system.
3521 Attach to an existing process on the remote system, in extended-remote
3525 Run a new process on the remote system, in extended-remote mode.
3527 *** Changes in GDB 6.7
3529 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3530 bfd, libiberty and opcodes, as revealed by static analysis donated by
3531 Coverity, Inc. (http://scan.coverity.com).
3533 * When looking up multiply-defined global symbols, GDB will now prefer the
3534 symbol definition in the current shared library if it was built using the
3535 -Bsymbolic linker option.
3537 * When the Text User Interface (TUI) is not configured, GDB will now
3538 recognize the -tui command-line option and print a message that the TUI
3541 * The GDB remote stub, gdbserver, now has lower overhead for high
3542 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3544 * GDB for MIPS targets now autodetects whether a remote target provides
3545 32-bit or 64-bit register values.
3547 * Support for C++ member pointers has been improved.
3549 * GDB now understands XML target descriptions, which specify the
3550 target's overall architecture. GDB can read a description from
3551 a local file or over the remote serial protocol.
3553 * Vectors of single-byte data use a new integer type which is not
3554 automatically displayed as character or string data.
3556 * The /s format now works with the print command. It displays
3557 arrays of single-byte integers and pointers to single-byte integers
3560 * Target descriptions can now describe target-specific registers,
3561 for architectures which have implemented the support (currently
3562 only ARM, M68K, and MIPS).
3564 * GDB and the GDB remote stub, gdbserver, now support the XScale
3567 * The GDB remote stub, gdbserver, has been updated to support
3568 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3569 has been rewritten to use the standard GDB remote protocol.
3571 * GDB can now step into C++ functions which are called through thunks.
3573 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3575 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3576 layout. It also supports a TextSeg= and DataSeg= response when only
3577 segment base addresses (rather than offsets) are available.
3579 * The /i format now outputs any trailing branch delay slot instructions
3580 immediately following the last instruction within the count specified.
3582 * The GDB remote protocol "T" stop reply packet now supports a
3583 "library" response. Combined with the new "qXfer:libraries:read"
3584 packet, this response allows GDB to debug shared libraries on targets
3585 where the operating system manages the list of loaded libraries (e.g.
3586 Windows and SymbianOS).
3588 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3589 (DLLs) on Windows and Windows CE targets.
3591 * GDB now supports a faster verification that a .debug file matches its binary
3592 according to its build-id signature, if the signature is present.
3598 Enable or disable hardware flow control (RTS/CTS) on the serial port
3599 when debugging using remote targets.
3601 set mem inaccessible-by-default
3602 show mem inaccessible-by-default
3603 If the target supplies a memory map, for instance via the remote
3604 protocol's "qXfer:memory-map:read" packet, setting this variable
3605 prevents GDB from accessing memory outside the memory map. This
3606 is useful for targets with memory mapped registers or which react
3607 badly to accesses of unmapped address space.
3609 set breakpoint auto-hw
3610 show breakpoint auto-hw
3611 If the target supplies a memory map, for instance via the remote
3612 protocol's "qXfer:memory-map:read" packet, setting this variable
3613 lets GDB use hardware breakpoints automatically for memory regions
3614 where it can not use software breakpoints. This covers both the
3615 "break" command and internal breakpoints used for other commands
3616 including "next" and "finish".
3619 catch exception unhandled
3620 Stop the program execution when Ada exceptions are raised.
3623 Stop the program execution when an Ada assertion failed.
3627 Set an alternate system root for target files. This is a more
3628 general version of "set solib-absolute-prefix", which is now
3629 an alias to "set sysroot".
3632 Provide extended SPU facility status information. This set of
3633 commands is available only when debugging the Cell/B.E. SPU
3636 * New native configurations
3638 OpenBSD/sh sh*-*openbsd*
3641 unset tdesc filename
3643 Use the specified local file as an XML target description, and do
3644 not query the target for its built-in description.
3648 OpenBSD/sh sh*-*-openbsd*
3649 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3650 Toshiba Media Processor mep-elf
3652 * New remote packets
3655 Ignore the specified signals; pass them directly to the debugged program
3656 without stopping other threads or reporting them to GDB.
3658 qXfer:features:read:
3659 Read an XML target description from the target, which describes its
3664 Read or write contents of an spufs file on the target system. These
3665 packets are available only on the Cell/B.E. SPU architecture.
3667 qXfer:libraries:read:
3668 Report the loaded shared libraries. Combined with new "T" packet
3669 response, this packet allows GDB to debug shared libraries on
3670 targets where the operating system manages the list of loaded
3671 libraries (e.g. Windows and SymbianOS).
3675 Support for these obsolete configurations has been removed.
3683 i[34567]86-*-lynxos*
3684 i[34567]86-*-netware*
3685 i[34567]86-*-sco3.2v5*
3686 i[34567]86-*-sco3.2v4*
3688 i[34567]86-*-sysv4.2*
3691 i[34567]86-*-unixware2*
3692 i[34567]86-*-unixware*
3701 * Other removed features
3708 Various m68k-only ROM monitors.
3715 Various Renesas ROM monitors and debugging interfaces for SH and
3720 Support for a Macraigor serial interface to on-chip debugging.
3721 GDB does not directly support the newer parallel or USB
3726 A debug information format. The predecessor to DWARF 2 and
3727 DWARF 3, which are still supported.
3729 Support for the HP aCC compiler on HP-UX/PA-RISC
3731 SOM-encapsulated symbolic debugging information, automatic
3732 invocation of pxdb, and the aCC custom C++ ABI. This does not
3733 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3734 with aCC can still be debugged on an assembly level.
3736 MIPS ".pdr" sections
3738 A MIPS-specific format used to describe stack frame layout
3739 in debugging information.
3743 GDB could work with an older version of Guile to debug
3744 the interpreter and Scheme programs running in it.
3746 set mips stack-arg-size
3747 set mips saved-gpreg-size
3749 Use "set mips abi" to control parameter passing for MIPS.
3751 *** Changes in GDB 6.6
3756 Cell Broadband Engine SPU spu-elf
3758 * GDB can now be configured as a cross-debugger targeting native Windows
3759 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3760 running on a Windows system over TCP/IP to debug Windows programs.
3762 * The GDB remote stub, gdbserver, has been updated to support Windows and
3763 Cygwin debugging. Both single-threaded and multi-threaded programs are
3766 * The "set trust-readonly-sections" command works again. This command was
3767 broken in GDB 6.3, 6.4, and 6.5.
3769 * The "load" command now supports writing to flash memory, if the remote
3770 stub provides the required support.
3772 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3773 longer requires symbolic debug information (e.g. DWARF-2).
3778 unset substitute-path
3779 show substitute-path
3780 Manage a list of substitution rules that GDB uses to rewrite the name
3781 of the directories where the sources are located. This can be useful
3782 for instance when the sources were moved to a different location
3783 between compilation and debugging.
3787 Print each CLI command as it is executed. Each command is prefixed with
3788 a number of `+' symbols representing the nesting depth.
3789 The source command now has a `-v' option to enable the same feature.
3793 The ARM Demon monitor support (RDP protocol, "target rdp").
3795 Kernel Object Display, an embedded debugging feature which only worked with
3796 an obsolete version of Cisco IOS.
3798 The 'set download-write-size' and 'show download-write-size' commands.
3800 * New remote packets
3803 Tell a stub about GDB client features, and request remote target features.
3804 The first feature implemented is PacketSize, which allows the target to
3805 specify the size of packets it can handle - to minimize the number of
3806 packets required and improve performance when connected to a remote
3810 Fetch an OS auxilliary vector from the remote stub. This packet is a
3811 more efficient replacement for qPart:auxv:read.
3813 qXfer:memory-map:read:
3814 Fetch a memory map from the remote stub, including information about
3815 RAM, ROM, and flash memory devices.
3820 Erase and program a flash memory device.
3822 * Removed remote packets
3825 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3826 used it, and only gdbserver implemented it.
3828 *** Changes in GDB 6.5
3832 Renesas M32C/M16C m32c-elf
3834 Morpho Technologies ms1 ms1-elf
3838 init-if-undefined Initialize a convenience variable, but
3839 only if it doesn't already have a value.
3841 The following commands are presently only implemented for native GNU/Linux:
3843 checkpoint Save a snapshot of the program state.
3845 restart <n> Return the program state to a
3846 previously saved state.
3848 info checkpoints List currently saved checkpoints.
3850 delete-checkpoint <n> Delete a previously saved checkpoint.
3852 set|show detach-on-fork Tell gdb whether to detach from a newly
3853 forked process, or to keep debugging it.
3855 info forks List forks of the user program that
3856 are available to be debugged.
3858 fork <n> Switch to debugging one of several
3859 forks of the user program that are
3860 available to be debugged.
3862 delete-fork <n> Delete a fork from the list of forks
3863 that are available to be debugged (and
3864 kill the forked process).
3866 detach-fork <n> Delete a fork from the list of forks
3867 that are available to be debugged (and
3868 allow the process to continue).
3872 Morpho Technologies ms2 ms1-elf
3874 * Improved Windows host support
3876 GDB now builds as a cross debugger hosted on i686-mingw32, including
3877 native console support, and remote communications using either
3878 network sockets or serial ports.
3880 * Improved Modula-2 language support
3882 GDB can now print most types in the Modula-2 syntax. This includes:
3883 basic types, set types, record types, enumerated types, range types,
3884 pointer types and ARRAY types. Procedure var parameters are correctly
3885 printed and hexadecimal addresses and character constants are also
3886 written in the Modula-2 syntax. Best results can be obtained by using
3887 GNU Modula-2 together with the -gdwarf-2 command line option.
3891 The ARM rdi-share module.
3893 The Netware NLM debug server.
3895 *** Changes in GDB 6.4
3897 * New native configurations
3899 OpenBSD/arm arm*-*-openbsd*
3900 OpenBSD/mips64 mips64-*-openbsd*
3904 Morpho Technologies ms1 ms1-elf
3906 * New command line options
3908 --batch-silent As for --batch, but totally silent.
3909 --return-child-result The debugger will exist with the same value
3910 the child (debugged) program exited with.
3911 --eval-command COMMAND, -ex COMMAND
3912 Execute a single GDB CLI command. This may be
3913 specified multiple times and in conjunction
3914 with the --command (-x) option.
3916 * Deprecated commands removed
3918 The following commands, that were deprecated in 2000, have been
3922 set|show arm disassembly-flavor set|show arm disassembler
3923 othernames set arm disassembler
3924 set|show remotedebug set|show debug remote
3925 set|show archdebug set|show debug arch
3926 set|show eventdebug set|show debug event
3929 * New BSD user-level threads support
3931 It is now possible to debug programs using the user-level threads
3932 library on OpenBSD and FreeBSD. Currently supported (target)
3935 FreeBSD/amd64 x86_64-*-freebsd*
3936 FreeBSD/i386 i386-*-freebsd*
3937 OpenBSD/i386 i386-*-openbsd*
3939 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3940 are not yet supported.
3942 * New support for Matsushita MN10300 w/sim added
3943 (Work in progress). mn10300-elf.
3945 * REMOVED configurations and files
3947 VxWorks and the XDR protocol *-*-vxworks
3948 Motorola MCORE mcore-*-*
3949 National Semiconductor NS32000 ns32k-*-*
3951 * New "set print array-indexes" command
3953 After turning this setting "on", GDB prints the index of each element
3954 when displaying arrays. The default is "off" to preserve the previous
3957 * VAX floating point support
3959 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3961 * User-defined command support
3963 In addition to using $arg0..$arg9 for argument passing, it is now possible
3964 to use $argc to determine now many arguments have been passed. See the
3965 section on user-defined commands in the user manual for more information.
3967 *** Changes in GDB 6.3:
3969 * New command line option
3971 GDB now accepts -l followed by a number to set the timeout for remote
3974 * GDB works with GCC -feliminate-dwarf2-dups
3976 GDB now supports a more compact representation of DWARF-2 debug
3977 information using DW_FORM_ref_addr references. These are produced
3978 by GCC with the option -feliminate-dwarf2-dups and also by some
3979 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3980 to use -feliminate-dwarf2-dups.
3982 * Internationalization
3984 When supported by the host system, GDB will be built with
3985 internationalization (libintl). The task of marking up the sources is
3986 continued, we're looking forward to our first translation.
3990 Initial support for debugging programs compiled with the GNAT
3991 implementation of the Ada programming language has been integrated
3992 into GDB. In this release, support is limited to expression evaluation.
3994 * New native configurations
3996 GNU/Linux/m32r m32r-*-linux-gnu
4000 GDB's remote protocol now includes support for the 'p' packet. This
4001 packet is used to fetch individual registers from a remote inferior.
4003 * END-OF-LIFE registers[] compatibility module
4005 GDB's internal register infrastructure has been completely rewritten.
4006 The new infrastructure making possible the implementation of key new
4007 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4010 GDB 6.3 will be the last release to include the the registers[]
4011 compatibility module that allowed out-of-date configurations to
4012 continue to work. This change directly impacts the following
4022 powerpc bdm protocol
4024 Unless there is activity to revive these configurations, they will be
4025 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4027 * OBSOLETE configurations and files
4029 Configurations that have been declared obsolete in this release have
4030 been commented out. Unless there is activity to revive these
4031 configurations, the next release of GDB will have their sources
4032 permanently REMOVED.
4041 *** Changes in GDB 6.2.1:
4043 * MIPS `break main; run' gave an heuristic-fence-post warning
4045 When attempting to run even a simple program, a warning about
4046 heuristic-fence-post being hit would be reported. This problem has
4049 * MIPS IRIX 'long double' crashed GDB
4051 When examining a long double variable, GDB would get a segmentation
4052 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4053 IRIX long double values).
4057 A bug in the VAX stack code was causing problems with the "next"
4058 command. This problem has been fixed.
4060 *** Changes in GDB 6.2:
4062 * Fix for ``many threads''
4064 On GNU/Linux systems that use the NPTL threads library, a program
4065 rapidly creating and deleting threads would confuse GDB leading to the
4068 ptrace: No such process.
4069 thread_db_get_info: cannot get thread info: generic error
4071 This problem has been fixed.
4073 * "-async" and "-noasync" options removed.
4075 Support for the broken "-noasync" option has been removed (it caused
4078 * New ``start'' command.
4080 This command runs the program until the begining of the main procedure.
4082 * New BSD Kernel Data Access Library (libkvm) interface
4084 Using ``target kvm'' it is now possible to debug kernel core dumps and
4085 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4086 platforms. Currently supported (native-only) configurations are:
4088 FreeBSD/amd64 x86_64-*-freebsd*
4089 FreeBSD/i386 i?86-*-freebsd*
4090 NetBSD/i386 i?86-*-netbsd*
4091 NetBSD/m68k m68*-*-netbsd*
4092 NetBSD/sparc sparc-*-netbsd*
4093 OpenBSD/amd64 x86_64-*-openbsd*
4094 OpenBSD/i386 i?86-*-openbsd*
4095 OpenBSD/m68k m68*-openbsd*
4096 OpenBSD/sparc sparc-*-openbsd*
4098 * Signal trampoline code overhauled
4100 Many generic problems with GDB's signal handling code have been fixed.
4101 These include: backtraces through non-contiguous stacks; recognition
4102 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4103 call; backtrace through a signal trampoline; step into and out of
4104 signal handlers; and single-stepping in the signal trampoline.
4106 Please note that kernel bugs are a limiting factor here. These
4107 features have been shown to work on an s390 GNU/Linux system that
4108 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4110 * Cygwin support for DWARF 2 added.
4112 * New native configurations
4114 GNU/Linux/hppa hppa*-*-linux*
4115 OpenBSD/hppa hppa*-*-openbsd*
4116 OpenBSD/m68k m68*-*-openbsd*
4117 OpenBSD/m88k m88*-*-openbsd*
4118 OpenBSD/powerpc powerpc-*-openbsd*
4119 NetBSD/vax vax-*-netbsd*
4120 OpenBSD/vax vax-*-openbsd*
4122 * END-OF-LIFE frame compatibility module
4124 GDB's internal frame infrastructure has been completely rewritten.
4125 The new infrastructure making it possible to support key new features
4126 including DWARF 2 Call Frame Information. To aid in the task of
4127 migrating old configurations to this new infrastructure, a
4128 compatibility module, that allowed old configurations to continue to
4129 work, was also included.
4131 GDB 6.2 will be the last release to include this frame compatibility
4132 module. This change directly impacts the following configurations:
4142 Unless there is activity to revive these configurations, they will be
4143 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4145 * REMOVED configurations and files
4147 Sun 3, running SunOS 3 m68*-*-sunos3*
4148 Sun 3, running SunOS 4 m68*-*-sunos4*
4149 Sun 2, running SunOS 3 m68000-*-sunos3*
4150 Sun 2, running SunOS 4 m68000-*-sunos4*
4151 Motorola 680x0 running LynxOS m68*-*-lynxos*
4152 AT&T 3b1/Unix pc m68*-att-*
4153 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4154 decstation mips-dec-* mips-little-*
4155 riscos mips-*-riscos* mips-*-sysv*
4156 sonymips mips-sony-*
4157 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4159 *** Changes in GDB 6.1.1:
4161 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4163 The TUI (Text-mode User Interface) is now built as part of a default
4164 GDB configuration. It is enabled by either selecting the TUI with the
4165 command line option "-i=tui" or by running the separate "gdbtui"
4166 program. For more information on the TUI, see the manual "Debugging
4169 * Pending breakpoint support (also included in GDB 6.1)
4171 Support has been added to allow you to specify breakpoints in shared
4172 libraries that have not yet been loaded. If a breakpoint location
4173 cannot be found, and the "breakpoint pending" option is set to auto,
4174 GDB queries you if you wish to make the breakpoint pending on a future
4175 shared-library load. If and when GDB resolves the breakpoint symbol,
4176 the pending breakpoint is removed as one or more regular breakpoints
4179 Pending breakpoints are very useful for GCJ Java debugging.
4181 * Fixed ISO-C build problems
4183 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4184 non ISO-C code that stopped them being built using a more strict ISO-C
4185 compiler (e.g., IBM's C compiler).
4187 * Fixed build problem on IRIX 5
4189 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4190 wasn't able to compile compile on an IRIX 5 system.
4192 * Added execute permission to gdb/gdbserver/configure
4194 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4195 permission. This bug would cause configure to fail on a number of
4196 systems (Solaris, IRIX). Ref: server/519.
4198 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4200 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4201 has been updated to use constant array sizes.
4203 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4205 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4206 its generated DWARF Call Frame Info. This encoding was causing GDB to
4207 panic, that panic has been fixed. Ref: gdb/1628.
4209 * Fixed a problem when examining parameters in shared library code.
4211 When examining parameters in optimized shared library code generated
4212 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4213 not available''. GDB now correctly displays the variable's value.
4215 *** Changes in GDB 6.1:
4217 * Removed --with-mmalloc
4219 Support for the mmalloc memory manager has been removed, as it
4220 conflicted with the internal gdb byte cache.
4222 * Changes in AMD64 configurations
4224 The AMD64 target now includes the %cs and %ss registers. As a result
4225 the AMD64 remote protocol has changed; this affects the floating-point
4226 and SSE registers. If you rely on those registers for your debugging,
4227 you should upgrade gdbserver on the remote side.
4229 * Revised SPARC target
4231 The SPARC target has been completely revised, incorporating the
4232 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4233 support for LynxOS and SunOS 4 has been dropped. Calling functions
4234 from within GDB on operating systems with a non-executable stack
4235 (Solaris, OpenBSD) now works.
4239 GDB has a new C++ demangler which does a better job on the mangled
4240 names generated by current versions of g++. It also runs faster, so
4241 with this and other changes gdb should now start faster on large C++
4244 * DWARF 2 Location Expressions
4246 GDB support for location expressions has been extended to support function
4247 arguments and frame bases. Older versions of GDB could crash when they
4250 * C++ nested types and namespaces
4252 GDB's support for nested types and namespaces in C++ has been
4253 improved, especially if you use the DWARF 2 debugging format. (This
4254 is the default for recent versions of GCC on most platforms.)
4255 Specifically, if you have a class "Inner" defined within a class or
4256 namespace "Outer", then GDB realizes that the class's name is
4257 "Outer::Inner", not simply "Inner". This should greatly reduce the
4258 frequency of complaints about not finding RTTI symbols. In addition,
4259 if you are stopped at inside of a function defined within a namespace,
4260 GDB modifies its name lookup accordingly.
4262 * New native configurations
4264 NetBSD/amd64 x86_64-*-netbsd*
4265 OpenBSD/amd64 x86_64-*-openbsd*
4266 OpenBSD/alpha alpha*-*-openbsd*
4267 OpenBSD/sparc sparc-*-openbsd*
4268 OpenBSD/sparc64 sparc64-*-openbsd*
4270 * New debugging protocols
4272 M32R with SDI protocol m32r-*-elf*
4274 * "set prompt-escape-char" command deleted.
4276 The command "set prompt-escape-char" has been deleted. This command,
4277 and its very obscure effet on GDB's prompt, was never documented,
4278 tested, nor mentioned in the NEWS file.
4280 * OBSOLETE configurations and files
4282 Configurations that have been declared obsolete in this release have
4283 been commented out. Unless there is activity to revive these
4284 configurations, the next release of GDB will have their sources
4285 permanently REMOVED.
4287 Sun 3, running SunOS 3 m68*-*-sunos3*
4288 Sun 3, running SunOS 4 m68*-*-sunos4*
4289 Sun 2, running SunOS 3 m68000-*-sunos3*
4290 Sun 2, running SunOS 4 m68000-*-sunos4*
4291 Motorola 680x0 running LynxOS m68*-*-lynxos*
4292 AT&T 3b1/Unix pc m68*-att-*
4293 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4294 decstation mips-dec-* mips-little-*
4295 riscos mips-*-riscos* mips-*-sysv*
4296 sonymips mips-sony-*
4297 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4299 * REMOVED configurations and files
4301 SGI Irix-4.x mips-sgi-irix4 or iris4
4302 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4303 Z8000 simulator z8k-zilog-none or z8ksim
4304 Matsushita MN10200 w/simulator mn10200-*-*
4305 H8/500 simulator h8500-hitachi-hms or h8500hms
4306 HP/PA running BSD hppa*-*-bsd*
4307 HP/PA running OSF/1 hppa*-*-osf*
4308 HP/PA Pro target hppa*-*-pro*
4309 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4310 386BSD i[3456]86-*-bsd*
4311 Sequent family i[3456]86-sequent-sysv4*
4312 i[3456]86-sequent-sysv*
4313 i[3456]86-sequent-bsd*
4314 SPARC running LynxOS sparc-*-lynxos*
4315 SPARC running SunOS 4 sparc-*-sunos4*
4316 Tsqware Sparclet sparclet-*-*
4317 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4319 *** Changes in GDB 6.0:
4323 Support for debugging the Objective-C programming language has been
4324 integrated into GDB.
4326 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4328 DWARF 2's Call Frame Information makes available compiler generated
4329 information that more exactly describes the program's run-time stack.
4330 By using this information, GDB is able to provide more robust stack
4333 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4334 have been updated to use a new backtrace mechanism which includes
4335 DWARF 2 CFI support.
4339 GDB's remote protocol has been extended to include support for hosted
4340 file I/O (where the remote target uses GDB's file system). See GDB's
4341 remote protocol documentation for details.
4343 * All targets using the new architecture framework.
4345 All of GDB's targets have been updated to use the new internal
4346 architecture framework. The way is now open for future GDB releases
4347 to include cross-architecture native debugging support (i386 on amd64,
4350 * GNU/Linux's Thread Local Storage (TLS)
4352 GDB now includes support for for the GNU/Linux implementation of
4353 per-thread variables.
4355 * GNU/Linux's Native POSIX Thread Library (NPTL)
4357 GDB's thread code has been updated to work with either the new
4358 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4360 * Separate debug info.
4362 GDB, in conjunction with BINUTILS, now supports a mechanism for
4363 automatically loading debug information from a separate file. Instead
4364 of shipping full debug and non-debug versions of system libraries,
4365 system integrators can now instead ship just the stripped libraries
4366 and optional debug files.
4368 * DWARF 2 Location Expressions
4370 DWARF 2 Location Expressions allow the compiler to more completely
4371 describe the location of variables (even in optimized code) to the
4374 GDB now includes preliminary support for location expressions (support
4375 for DW_OP_piece is still missing).
4379 A number of long standing bugs that caused GDB to die while starting a
4380 Java application have been fixed. GDB's Java support is now
4381 considered "useable".
4383 * GNU/Linux support for fork, vfork, and exec.
4385 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4386 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4389 * GDB supports logging output to a file
4391 There are two new commands, "set logging" and "show logging", which can be
4392 used to capture GDB's output to a file.
4394 * The meaning of "detach" has changed for gdbserver
4396 The "detach" command will now resume the application, as documented. To
4397 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4400 * d10v, m68hc11 `regs' command deprecated
4402 The `info registers' command has been updated so that it displays the
4403 registers using a format identical to the old `regs' command.
4407 A new command, "maint set profile on/off", has been added. This command can
4408 be used to enable or disable profiling while running GDB, to profile a
4409 session or a set of commands. In addition there is a new configure switch,
4410 "--enable-profiling", which will cause GDB to be compiled with profiling
4411 data, for more informative profiling results.
4413 * Default MI syntax changed to "mi2".
4415 The default MI (machine interface) syntax, enabled by the command line
4416 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4417 "mi1", can be enabled by specifying the option "-i=mi1".
4419 Support for the original "mi0" syntax (included in GDB 5.0) has been
4422 Fix for gdb/192: removed extraneous space when displaying frame level.
4423 Fix for gdb/672: update changelist is now output in mi list format.
4424 Fix for gdb/702: a -var-assign that updates the value now shows up
4425 in a subsequent -var-update.
4427 * New native configurations.
4429 FreeBSD/amd64 x86_64-*-freebsd*
4431 * Multi-arched targets.
4433 HP/PA HPUX11 hppa*-*-hpux*
4434 Renesas M32R/D w/simulator m32r-*-elf*
4436 * OBSOLETE configurations and files
4438 Configurations that have been declared obsolete in this release have
4439 been commented out. Unless there is activity to revive these
4440 configurations, the next release of GDB will have their sources
4441 permanently REMOVED.
4443 Z8000 simulator z8k-zilog-none or z8ksim
4444 Matsushita MN10200 w/simulator mn10200-*-*
4445 H8/500 simulator h8500-hitachi-hms or h8500hms
4446 HP/PA running BSD hppa*-*-bsd*
4447 HP/PA running OSF/1 hppa*-*-osf*
4448 HP/PA Pro target hppa*-*-pro*
4449 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4450 Sequent family i[3456]86-sequent-sysv4*
4451 i[3456]86-sequent-sysv*
4452 i[3456]86-sequent-bsd*
4453 Tsqware Sparclet sparclet-*-*
4454 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4456 * REMOVED configurations and files
4459 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4460 IBM AIX PS/2 i[3456]86-*-aix
4461 i386 running Mach 3.0 i[3456]86-*-mach3*
4462 i386 running Mach i[3456]86-*-mach*
4463 i386 running OSF/1 i[3456]86-*osf1mk*
4464 HP/Apollo 68k Family m68*-apollo*-sysv*,
4466 m68*-hp-bsd*, m68*-hp-hpux*
4467 Argonaut Risc Chip (ARC) arc-*-*
4468 Mitsubishi D30V d30v-*-*
4469 Fujitsu FR30 fr30-*-elf*
4470 OS/9000 i[34]86-*-os9k
4471 I960 with MON960 i960-*-coff
4473 * MIPS $fp behavior changed
4475 The convenience variable $fp, for the MIPS, now consistently returns
4476 the address of the current frame's base. Previously, depending on the
4477 context, $fp could refer to either $sp or the current frame's base
4478 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4479 The GNU Source-Level Debugger''.
4481 *** Changes in GDB 5.3:
4483 * GNU/Linux shared library multi-threaded performance improved.
4485 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4486 `/proc', in preference to `ptrace' for memory reads. This may result
4487 in an improvement in the start-up time of multi-threaded, shared
4488 library applications when run under GDB. One GDB user writes: ``loads
4489 shared libs like mad''.
4491 * ``gdbserver'' now supports multi-threaded applications on some targets
4493 Support for debugging multi-threaded applications which use
4494 the GNU/Linux LinuxThreads package has been added for
4495 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4496 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4498 * GDB now supports C/C++ preprocessor macros.
4500 GDB now expands preprocessor macro invocations in C/C++ expressions,
4501 and provides various commands for showing macro definitions and how
4504 The new command `macro expand EXPRESSION' expands any macro
4505 invocations in expression, and shows the result.
4507 The new command `show macro MACRO-NAME' shows the definition of the
4508 macro named MACRO-NAME, and where it was defined.
4510 Most compilers don't include information about macros in the debugging
4511 information by default. In GCC 3.1, for example, you need to compile
4512 your program with the options `-gdwarf-2 -g3'. If the macro
4513 information is present in the executable, GDB will read it.
4515 * Multi-arched targets.
4517 DEC Alpha (partial) alpha*-*-*
4518 DEC VAX (partial) vax-*-*
4520 National Semiconductor NS32000 (partial) ns32k-*-*
4521 Motorola 68000 (partial) m68k-*-*
4522 Motorola MCORE mcore-*-*
4526 Fujitsu FRV architecture added by Red Hat frv*-*-*
4529 * New native configurations
4531 Alpha NetBSD alpha*-*-netbsd*
4532 SH NetBSD sh*-*-netbsdelf*
4533 MIPS NetBSD mips*-*-netbsd*
4534 UltraSPARC NetBSD sparc64-*-netbsd*
4536 * OBSOLETE configurations and files
4538 Configurations that have been declared obsolete in this release have
4539 been commented out. Unless there is activity to revive these
4540 configurations, the next release of GDB will have their sources
4541 permanently REMOVED.
4543 Mitsubishi D30V d30v-*-*
4544 OS/9000 i[34]86-*-os9k
4545 IBM AIX PS/2 i[3456]86-*-aix
4546 Fujitsu FR30 fr30-*-elf*
4547 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4548 Argonaut Risc Chip (ARC) arc-*-*
4549 i386 running Mach 3.0 i[3456]86-*-mach3*
4550 i386 running Mach i[3456]86-*-mach*
4551 i386 running OSF/1 i[3456]86-*osf1mk*
4552 HP/Apollo 68k Family m68*-apollo*-sysv*,
4554 m68*-hp-bsd*, m68*-hp-hpux*
4555 I960 with MON960 i960-*-coff
4557 * OBSOLETE languages
4559 CHILL, a Pascal like language used by telecommunications companies.
4561 * REMOVED configurations and files
4563 AMD 29k family via UDI a29k-amd-udi, udi29k
4564 A29K VxWorks a29k-*-vxworks
4565 AMD 29000 embedded, using EBMON a29k-none-none
4566 AMD 29000 embedded with COFF a29k-none-coff
4567 AMD 29000 embedded with a.out a29k-none-aout
4569 testsuite/gdb.hp/gdb.threads-hp/ directory
4571 * New command "set max-user-call-depth <nnn>"
4573 This command allows the user to limit the call depth of user-defined
4574 commands. The default is 1024.
4576 * Changes in FreeBSD/i386 native debugging.
4578 Support for the "generate-core-file" has been added.
4580 * New commands "dump", "append", and "restore".
4582 These commands allow data to be copied from target memory
4583 to a bfd-format or binary file (dump and append), and back
4584 from a file into memory (restore).
4586 * Improved "next/step" support on multi-processor Alpha Tru64.
4588 The previous single-step mechanism could cause unpredictable problems,
4589 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4590 of a software single-step mechanism prevents this.
4592 *** Changes in GDB 5.2.1:
4600 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4601 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4602 Fix, by Joel Brobecker imported from mainline.
4604 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4605 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4606 Fix, by Fred Fish, imported from mainline.
4608 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4609 Surprisingly enough, it works now.
4610 By Michal Ludvig, imported from mainline.
4612 i386 hardware watchpoint support:
4613 avoid misses on second run for some targets.
4614 By Pierre Muller, imported from mainline.
4616 *** Changes in GDB 5.2:
4618 * New command "set trust-readonly-sections on[off]".
4620 This command is a hint that tells gdb that read-only sections
4621 really are read-only (ie. that their contents will not change).
4622 In this mode, gdb will go to the object file rather than the
4623 target to read memory from read-only sections (such as ".text").
4624 This can be a significant performance improvement on some
4625 (notably embedded) targets.
4627 * New command "generate-core-file" (or "gcore").
4629 This new gdb command allows the user to drop a core file of the child
4630 process state at any time. So far it's been implemented only for
4631 GNU/Linux and Solaris, but should be relatively easily ported to other
4632 hosts. Argument is core file name (defaults to core.<pid>).
4634 * New command line option
4636 GDB now accepts --pid or -p followed by a process id.
4638 * Change in command line behavior -- corefiles vs. process ids.
4640 There is a subtle behavior in the way in which GDB handles
4641 command line arguments. The first non-flag argument is always
4642 a program to debug, but the second non-flag argument may either
4643 be a corefile or a process id. Previously, GDB would attempt to
4644 open the second argument as a corefile, and if that failed, would
4645 issue a superfluous error message and then attempt to attach it as
4646 a process. Now, if the second argument begins with a non-digit,
4647 it will be treated as a corefile. If it begins with a digit,
4648 GDB will attempt to attach it as a process, and if no such process
4649 is found, will then attempt to open it as a corefile.
4651 * Changes in ARM configurations.
4653 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4654 configuration is fully multi-arch.
4656 * New native configurations
4658 ARM NetBSD arm*-*-netbsd*
4659 x86 OpenBSD i[3456]86-*-openbsd*
4660 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4661 Sparc64 running FreeBSD sparc64-*-freebsd*
4665 Sanyo XStormy16 xstormy16-elf
4667 * OBSOLETE configurations and files
4669 Configurations that have been declared obsolete in this release have
4670 been commented out. Unless there is activity to revive these
4671 configurations, the next release of GDB will have their sources
4672 permanently REMOVED.
4674 AMD 29k family via UDI a29k-amd-udi, udi29k
4675 A29K VxWorks a29k-*-vxworks
4676 AMD 29000 embedded, using EBMON a29k-none-none
4677 AMD 29000 embedded with COFF a29k-none-coff
4678 AMD 29000 embedded with a.out a29k-none-aout
4680 testsuite/gdb.hp/gdb.threads-hp/ directory
4682 * REMOVED configurations and files
4684 TI TMS320C80 tic80-*-*
4686 PowerPC Solaris powerpcle-*-solaris*
4687 PowerPC Windows NT powerpcle-*-cygwin32
4688 PowerPC Netware powerpc-*-netware*
4689 Harris/CXUX m88k m88*-harris-cxux*
4690 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4691 ns32k-utek-sysv* ns32k-utek-*
4692 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4693 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4694 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4695 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4696 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4698 * Changes to command line processing
4700 The new `--args' feature can be used to specify command-line arguments
4701 for the inferior from gdb's command line.
4703 * Changes to key bindings
4705 There is a new `operate-and-get-next' function bound to `C-o'.
4707 *** Changes in GDB 5.1.1
4709 Fix compile problem on DJGPP.
4711 Fix a problem with floating-point registers on the i386 being
4714 Fix to stop GDB crashing on .debug_str debug info.
4716 Numerous documentation fixes.
4718 Numerous testsuite fixes.
4720 *** Changes in GDB 5.1:
4722 * New native configurations
4724 Alpha FreeBSD alpha*-*-freebsd*
4725 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4726 MIPS GNU/Linux mips*-*-linux*
4727 MIPS SGI Irix 6.x mips*-sgi-irix6*
4728 ia64 AIX ia64-*-aix*
4729 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4733 Motorola 68HC11 and 68HC12 m68hc11-elf
4735 UltraSparc running GNU/Linux sparc64-*-linux*
4737 * OBSOLETE configurations and files
4739 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4740 Harris/CXUX m88k m88*-harris-cxux*
4741 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4742 ns32k-utek-sysv* ns32k-utek-*
4743 TI TMS320C80 tic80-*-*
4745 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4746 PowerPC Solaris powerpcle-*-solaris*
4747 PowerPC Windows NT powerpcle-*-cygwin32
4748 PowerPC Netware powerpc-*-netware*
4749 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4750 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4751 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4752 Apple Macintosh (MPW) host N/A
4754 stuff.c (Program to stuff files into a specially prepared space in kdb)
4755 kdb-start.c (Main loop for the standalone kernel debugger)
4757 Configurations that have been declared obsolete in this release have
4758 been commented out. Unless there is activity to revive these
4759 configurations, the next release of GDB will have their sources
4760 permanently REMOVED.
4762 * REMOVED configurations and files
4764 Altos 3068 m68*-altos-*
4765 Convex c1-*-*, c2-*-*
4767 ARM RISCix arm-*-* (as host)
4771 * GDB has been converted to ISO C.
4773 GDB's source code has been converted to ISO C. In particular, the
4774 sources are fully protoized, and rely on standard headers being
4779 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4781 * The MI enabled by default.
4783 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4784 revised and enabled by default. Packages which use GDB as a debugging
4785 engine behind a UI or another front end are encouraged to switch to
4786 using the GDB/MI interface, instead of the old annotations interface
4787 which is now deprecated.
4789 * Support for debugging Pascal programs.
4791 GDB now includes support for debugging Pascal programs. The following
4792 main features are supported:
4794 - Pascal-specific data types such as sets;
4796 - automatic recognition of Pascal sources based on file-name
4799 - Pascal-style display of data types, variables, and functions;
4801 - a Pascal expression parser.
4803 However, some important features are not yet supported.
4805 - Pascal string operations are not supported at all;
4807 - there are some problems with boolean types;
4809 - Pascal type hexadecimal constants are not supported
4810 because they conflict with the internal variables format;
4812 - support for Pascal objects and classes is not full yet;
4814 - unlike Pascal, GDB is case-sensitive for symbol names.
4816 * Changes in completion.
4818 Commands such as `shell', `run' and `set args', which pass arguments
4819 to inferior programs, now complete on file names, similar to what
4820 users expect at the shell prompt.
4822 Commands which accept locations, such as `disassemble', `print',
4823 `breakpoint', `until', etc. now complete on filenames as well as
4824 program symbols. Thus, if you type "break foob TAB", and the source
4825 files linked into the programs include `foobar.c', that file name will
4826 be one of the candidates for completion. However, file names are not
4827 considered for completion after you typed a colon that delimits a file
4828 name from a name of a function in that file, as in "break foo.c:bar".
4830 `set demangle-style' completes on available demangling styles.
4832 * New platform-independent commands:
4834 It is now possible to define a post-hook for a command as well as a
4835 hook that runs before the command. For more details, see the
4836 documentation of `hookpost' in the GDB manual.
4838 * Changes in GNU/Linux native debugging.
4840 Support for debugging multi-threaded programs has been completely
4841 revised for all platforms except m68k and sparc. You can now debug as
4842 many threads as your system allows you to have.
4844 Attach/detach is supported for multi-threaded programs.
4846 Support for SSE registers was added for x86. This doesn't work for
4847 multi-threaded programs though.
4849 * Changes in MIPS configurations.
4851 Multi-arch support is enabled for all MIPS configurations.
4853 GDB can now be built as native debugger on SGI Irix 6.x systems for
4854 debugging n32 executables. (Debugging 64-bit executables is not yet
4857 * Unified support for hardware watchpoints in all x86 configurations.
4859 Most (if not all) native x86 configurations support hardware-assisted
4860 breakpoints and watchpoints in a unified manner. This support
4861 implements debug register sharing between watchpoints, which allows to
4862 put a virtually infinite number of watchpoints on the same address,
4863 and also supports watching regions up to 16 bytes with several debug
4866 The new maintenance command `maintenance show-debug-regs' toggles
4867 debugging print-outs in functions that insert, remove, and test
4868 watchpoints and hardware breakpoints.
4870 * Changes in the DJGPP native configuration.
4872 New command ``info dos sysinfo'' displays assorted information about
4873 the CPU, OS, memory, and DPMI server.
4875 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4876 display information about segment descriptors stored in GDT, LDT, and
4879 New commands ``info dos pde'' and ``info dos pte'' display entries
4880 from Page Directory and Page Tables (for now works with CWSDPMI only).
4881 New command ``info dos address-pte'' displays the Page Table entry for
4882 a given linear address.
4884 GDB can now pass command lines longer than 126 characters to the
4885 program being debugged (requires an update to the libdbg.a library
4886 which is part of the DJGPP development kit).
4888 DWARF2 debug info is now supported.
4890 It is now possible to `step' and `next' through calls to `longjmp'.
4892 * Changes in documentation.
4894 All GDB documentation was converted to GFDL, the GNU Free
4895 Documentation License.
4897 Tracepoints-related commands are now fully documented in the GDB
4900 TUI, the Text-mode User Interface, is now documented in the manual.
4902 Tracepoints-related commands are now fully documented in the GDB
4905 The "GDB Internals" manual now has an index. It also includes
4906 documentation of `ui_out' functions, GDB coding standards, x86
4907 hardware watchpoints, and memory region attributes.
4909 * GDB's version number moved to ``version.in''
4911 The Makefile variable VERSION has been replaced by the file
4912 ``version.in''. People creating GDB distributions should update the
4913 contents of this file.
4917 GUD support is now a standard part of the EMACS distribution.
4919 *** Changes in GDB 5.0:
4921 * Improved support for debugging FP programs on x86 targets
4923 Unified and much-improved support for debugging floating-point
4924 programs on all x86 targets. In particular, ``info float'' now
4925 displays the FP registers in the same format on all x86 targets, with
4926 greater level of detail.
4928 * Improvements and bugfixes in hardware-assisted watchpoints
4930 It is now possible to watch array elements, struct members, and
4931 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4932 on x86 targets no longer erroneously trigger when the address is
4935 * Improvements in the native DJGPP version of GDB
4937 The distribution now includes all the scripts and auxiliary files
4938 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4939 machines ``out of the box''.
4941 The DJGPP version can now debug programs that use signals. It is
4942 possible to catch signals that happened in the debuggee, deliver
4943 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4944 would kill the program being debugged.) Programs that hook hardware
4945 interrupts (keyboard, timer, etc.) can also be debugged.
4947 It is now possible to debug DJGPP programs that redirect their
4948 standard handles or switch them to raw (as opposed to cooked) mode, or
4949 even close them. The command ``run < foo > bar'' works as expected,
4950 and ``info terminal'' reports useful information about the debuggee's
4951 terminal, including raw/cooked mode, redirection, etc.
4953 The DJGPP version now uses termios functions for console I/O, which
4954 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4957 DOS-style file names with drive letters are now fully supported by
4960 It is now possible to debug DJGPP programs that switch their working
4961 directory. It is also possible to rerun the debuggee any number of
4962 times without restarting GDB; thus, you can use the same setup,
4963 breakpoints, etc. for many debugging sessions.
4965 * New native configurations
4967 ARM GNU/Linux arm*-*-linux*
4968 PowerPC GNU/Linux powerpc-*-linux*
4972 Motorola MCore mcore-*-*
4973 x86 VxWorks i[3456]86-*-vxworks*
4974 PowerPC VxWorks powerpc-*-vxworks*
4975 TI TMS320C80 tic80-*-*
4977 * OBSOLETE configurations
4979 Altos 3068 m68*-altos-*
4980 Convex c1-*-*, c2-*-*
4982 ARM RISCix arm-*-* (as host)
4985 Configurations that have been declared obsolete will be commented out,
4986 but the code will be left in place. If there is no activity to revive
4987 these configurations before the next release of GDB, the sources will
4988 be permanently REMOVED.
4990 * Gould support removed
4992 Support for the Gould PowerNode and NP1 has been removed.
4994 * New features for SVR4
4996 On SVR4 native platforms (such as Solaris), if you attach to a process
4997 without first loading a symbol file, GDB will now attempt to locate and
4998 load symbols from the running process's executable file.
5000 * Many C++ enhancements
5002 C++ support has been greatly improved. Overload resolution now works properly
5003 in almost all cases. RTTI support is on the way.
5005 * Remote targets can connect to a sub-program
5007 A popen(3) style serial-device has been added. This device starts a
5008 sub-process (such as a stand-alone simulator) and then communicates
5009 with that. The sub-program to run is specified using the syntax
5010 ``|<program> <args>'' vis:
5012 (gdb) set remotedebug 1
5013 (gdb) target extended-remote |mn10300-elf-sim program-args
5015 * MIPS 64 remote protocol
5017 A long standing bug in the mips64 remote protocol where by GDB
5018 expected certain 32 bit registers (ex SR) to be transfered as 32
5019 instead of 64 bits has been fixed.
5021 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5022 added to provide backward compatibility with older versions of GDB.
5024 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5026 The command ``set remotebinarydownload'' command has been replaced by
5027 ``set remote X-packet''. Other commands in ``set remote'' family
5028 include ``set remote P-packet''.
5030 * Breakpoint commands accept ranges.
5032 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5033 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5034 ``tracepoint passcount'' also accepts a range of tracepoints.
5036 * ``apropos'' command added.
5038 The ``apropos'' command searches through command names and
5039 documentation strings, printing out matches, making it much easier to
5040 try to find a command that does what you are looking for.
5044 A new machine oriented interface (MI) has been added to GDB. This
5045 interface is designed for debug environments running GDB as a separate
5046 process. This is part of the long term libGDB project. See the
5047 "GDB/MI" chapter of the GDB manual for further information. It can be
5048 enabled by configuring with:
5050 .../configure --enable-gdbmi
5052 *** Changes in GDB-4.18:
5054 * New native configurations
5056 HP-UX 10.20 hppa*-*-hpux10.20
5057 HP-UX 11.x hppa*-*-hpux11.0*
5058 M68K GNU/Linux m68*-*-linux*
5062 Fujitsu FR30 fr30-*-elf*
5063 Intel StrongARM strongarm-*-*
5064 Mitsubishi D30V d30v-*-*
5066 * OBSOLETE configurations
5068 Gould PowerNode, NP1 np1-*-*, pn-*-*
5070 Configurations that have been declared obsolete will be commented out,
5071 but the code will be left in place. If there is no activity to revive
5072 these configurations before the next release of GDB, the sources will
5073 be permanently REMOVED.
5077 As a compatibility experiment, GDB's source files buildsym.h and
5078 buildsym.c have been converted to pure standard C, no longer
5079 containing any K&R compatibility code. We believe that all systems in
5080 use today either come with a standard C compiler, or have a GCC port
5081 available. If this is not true, please report the affected
5082 configuration to bug-gdb@gnu.org immediately. See the README file for
5083 information about getting a standard C compiler if you don't have one
5088 GDB now uses readline 2.2.
5090 * set extension-language
5092 You can now control the mapping between filename extensions and source
5093 languages by using the `set extension-language' command. For instance,
5094 you can ask GDB to treat .c files as C++ by saying
5095 set extension-language .c c++
5096 The command `info extensions' lists all of the recognized extensions
5097 and their associated languages.
5099 * Setting processor type for PowerPC and RS/6000
5101 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5102 you can use the `set processor' command to specify what variant of the
5103 PowerPC family you are debugging. The command
5107 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5108 following PowerPC and RS6000 variants:
5110 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5111 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5113 403GC IBM PowerPC 403GC
5114 505 Motorola PowerPC 505
5115 860 Motorola PowerPC 860 or 850
5116 601 Motorola PowerPC 601
5117 602 Motorola PowerPC 602
5118 603 Motorola/IBM PowerPC 603 or 603e
5119 604 Motorola PowerPC 604 or 604e
5120 750 Motorola/IBM PowerPC 750 or 750
5122 At the moment, this command just tells GDB what to name the
5123 special-purpose processor registers. Since almost all the affected
5124 registers are inaccessible to user-level programs, this command is
5125 only useful for remote debugging in its present form.
5129 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5130 more extensive support for HP-UX. Added features include shared
5131 library support, kernel threads and hardware watchpoints for 11.00,
5132 support for HP's ANSI C and C++ compilers, and a compatibility mode
5133 for xdb and dbx commands.
5137 HP's donation includes the new concept of catchpoints, which is a
5138 generalization of the old catch command. On HP-UX, it is now possible
5139 to catch exec, fork, and vfork, as well as library loading.
5141 This means that the existing catch command has changed; its first
5142 argument now specifies the type of catch to be set up. See the
5143 output of "help catch" for a list of catchpoint types.
5145 * Debugging across forks
5147 On HP-UX, you can choose which process to debug when a fork() happens
5152 HP has donated a curses-based terminal user interface (TUI). To get
5153 it, build with --enable-tui. Although this can be enabled for any
5154 configuration, at present it only works for native HP debugging.
5156 * GDB remote protocol additions
5158 A new protocol packet 'X' that writes binary data is now available.
5159 Default behavior is to try 'X', then drop back to 'M' if the stub
5160 fails to respond. The settable variable `remotebinarydownload'
5161 allows explicit control over the use of 'X'.
5163 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5164 full 64-bit address. The command
5166 set remoteaddresssize 32
5168 can be used to revert to the old behaviour. For existing remote stubs
5169 the change should not be noticed, as the additional address information
5172 In order to assist in debugging stubs, you may use the maintenance
5173 command `packet' to send any text string to the stub. For instance,
5175 maint packet heythere
5177 sends the packet "$heythere#<checksum>". Note that it is very easy to
5178 disrupt a debugging session by sending the wrong packet at the wrong
5181 The compare-sections command allows you to compare section data on the
5182 target to what is in the executable file without uploading or
5183 downloading, by comparing CRC checksums.
5185 * Tracing can collect general expressions
5187 You may now collect general expressions at tracepoints. This requires
5188 further additions to the target-side stub; see tracepoint.c and
5189 doc/agentexpr.texi for further details.
5191 * mask-address variable for Mips
5193 For Mips targets, you may control the zeroing of the upper 32 bits of
5194 a 64-bit address by entering `set mask-address on'. This is mainly
5195 of interest to users of embedded R4xxx and R5xxx processors.
5197 * Higher serial baud rates
5199 GDB's serial code now allows you to specify baud rates 57600, 115200,
5200 230400, and 460800 baud. (Note that your host system may not be able
5201 to achieve all of these rates.)
5205 The i960 configuration now includes an initial implementation of a
5206 builtin simulator, contributed by Jim Wilson.
5209 *** Changes in GDB-4.17:
5211 * New native configurations
5213 Alpha GNU/Linux alpha*-*-linux*
5214 Unixware 2.x i[3456]86-unixware2*
5215 Irix 6.x mips*-sgi-irix6*
5216 PowerPC GNU/Linux powerpc-*-linux*
5217 PowerPC Solaris powerpcle-*-solaris*
5218 Sparc GNU/Linux sparc-*-linux*
5219 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5223 Argonaut Risc Chip (ARC) arc-*-*
5224 Hitachi H8/300S h8300*-*-*
5225 Matsushita MN10200 w/simulator mn10200-*-*
5226 Matsushita MN10300 w/simulator mn10300-*-*
5227 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5228 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5229 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5230 Mitsubishi D10V w/simulator d10v-*-*
5231 Mitsubishi M32R/D w/simulator m32r-*-elf*
5232 Tsqware Sparclet sparclet-*-*
5233 NEC V850 w/simulator v850-*-*
5235 * New debugging protocols
5237 ARM with RDI protocol arm*-*-*
5238 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5239 DDB and LSI variants of PMON protocol mips*-*-*
5240 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5241 PowerPC with SDS protocol powerpc{,le}-*-eabi
5242 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5246 All configurations can now understand and use the DWARF 2 debugging
5247 format. The choice is automatic, if the symbol file contains DWARF 2
5252 GDB now includes basic Java language support. This support is
5253 only useful with Java compilers that produce native machine code.
5255 * solib-absolute-prefix and solib-search-path
5257 For SunOS and SVR4 shared libraries, you may now set the prefix for
5258 loading absolute shared library symbol files, and the search path for
5259 locating non-absolute shared library symbol files.
5261 * Live range splitting
5263 GDB can now effectively debug code for which GCC has performed live
5264 range splitting as part of its optimization. See gdb/doc/LRS for
5265 more details on the expected format of the stabs information.
5269 GDB's support for the GNU Hurd, including thread debugging, has been
5270 updated to work with current versions of the Hurd.
5274 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5275 instruction set. ARM GDB automatically detects when Thumb
5276 instructions are in use, and adjusts disassembly and backtracing
5281 GDB's MIPS target configurations now handle the MIP16 16-bit
5286 GDB now includes support for overlays; if an executable has been
5287 linked such that multiple sections are based at the same address, GDB
5288 will decide which section to use for symbolic info. You can choose to
5289 control the decision manually, using overlay commands, or implement
5290 additional target-side support and use "overlay load-target" to bring
5291 in the overlay mapping. Do "help overlay" for more detail.
5295 The command "info symbol <address>" displays information about
5296 the symbol at the specified address.
5300 The standard remote protocol now includes an extension that allows
5301 asynchronous collection and display of trace data. This requires
5302 extensive support in the target-side debugging stub. Tracing mode
5303 includes a new interaction mode in GDB and new commands: see the
5304 file tracepoint.c for more details.
5308 Configurations for embedded MIPS now include a simulator contributed
5309 by Cygnus Solutions. The simulator supports the instruction sets
5310 of most MIPS variants.
5314 Sparc configurations may now include the ERC32 simulator contributed
5315 by the European Space Agency. The simulator is not built into
5316 Sparc targets by default; configure with --enable-sim to include it.
5320 For target configurations that may include multiple variants of a
5321 basic architecture (such as MIPS and SH), you may now set the
5322 architecture explicitly. "set arch" sets, "info arch" lists
5323 the possible architectures.
5325 *** Changes in GDB-4.16:
5327 * New native configurations
5329 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5330 M68K NetBSD m68k-*-netbsd*
5331 PowerPC AIX 4.x powerpc-*-aix*
5332 PowerPC MacOS powerpc-*-macos*
5333 PowerPC Windows NT powerpcle-*-cygwin32
5334 RS/6000 AIX 4.x rs6000-*-aix4*
5338 ARM with RDP protocol arm-*-*
5339 I960 with MON960 i960-*-coff
5340 MIPS VxWorks mips*-*-vxworks*
5341 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5342 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5344 Matra Sparclet sparclet-*-*
5348 The powerpc-eabi configuration now includes the PSIM simulator,
5349 contributed by Andrew Cagney, with assistance from Mike Meissner.
5350 PSIM is a very elaborate model of the PowerPC, including not only
5351 basic instruction set execution, but also details of execution unit
5352 performance and I/O hardware. See sim/ppc/README for more details.
5356 GDB now works with Solaris 2.5.
5358 * Windows 95/NT native
5360 GDB will now work as a native debugger on Windows 95 and Windows NT.
5361 To build it from source, you must use the "gnu-win32" environment,
5362 which uses a DLL to emulate enough of Unix to run the GNU tools.
5363 Further information, binaries, and sources are available at
5364 ftp.cygnus.com, under pub/gnu-win32.
5366 * dont-repeat command
5368 If a user-defined command includes the command `dont-repeat', then the
5369 command will not be repeated if the user just types return. This is
5370 useful if the command is time-consuming to run, so that accidental
5371 extra keystrokes don't run the same command many times.
5373 * Send break instead of ^C
5375 The standard remote protocol now includes an option to send a break
5376 rather than a ^C to the target in order to interrupt it. By default,
5377 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5379 * Remote protocol timeout
5381 The standard remote protocol includes a new variable `remotetimeout'
5382 that allows you to set the number of seconds before GDB gives up trying
5383 to read from the target. The default value is 2.
5385 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5387 By default GDB will automatically keep track of objects as they are
5388 loaded and unloaded by the dynamic linker. By using the command `set
5389 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5390 when shared library events occur, thus allowing you to set breakpoints
5391 in shared libraries which are explicitly loaded by the inferior.
5393 Note this feature does not work on hpux8. On hpux9 you must link
5394 /usr/lib/end.o into your program. This feature should work
5395 automatically on hpux10.
5397 * Irix 5.x hardware watchpoint support
5399 Irix 5 configurations now support the use of hardware watchpoints.
5401 * Mips protocol "SYN garbage limit"
5403 When debugging a Mips target using the `target mips' protocol, you
5404 may set the number of characters that GDB will ignore by setting
5405 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5406 every character. The default value is 1050.
5408 * Recording and replaying remote debug sessions
5410 If you set `remotelogfile' to the name of a file, gdb will write to it
5411 a recording of a remote debug session. This recording may then be
5412 replayed back to gdb using "gdbreplay". See gdbserver/README for
5413 details. This is useful when you have a problem with GDB while doing
5414 remote debugging; you can make a recording of the session and send it
5415 to someone else, who can then recreate the problem.
5417 * Speedups for remote debugging
5419 GDB includes speedups for downloading and stepping MIPS systems using
5420 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5421 and more efficient S-record downloading.
5423 * Memory use reductions and statistics collection
5425 GDB now uses less memory and reports statistics about memory usage.
5426 Try the `maint print statistics' command, for example.
5428 *** Changes in GDB-4.15:
5430 * Psymtabs for XCOFF
5432 The symbol reader for AIX GDB now uses partial symbol tables. This
5433 can greatly improve startup time, especially for large executables.
5435 * Remote targets use caching
5437 Remote targets now use a data cache to speed up communication with the
5438 remote side. The data cache could lead to incorrect results because
5439 it doesn't know about volatile variables, thus making it impossible to
5440 debug targets which use memory mapped I/O devices. `set remotecache
5441 off' turns the the data cache off.
5443 * Remote targets may have threads
5445 The standard remote protocol now includes support for multiple threads
5446 in the target system, using new protocol commands 'H' and 'T'. See
5447 gdb/remote.c for details.
5451 If GDB is configured with `--enable-netrom', then it will include
5452 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5453 acts as though it is a bank of ROM on the target board, but you can
5454 write into it over the network. GDB's support consists only of
5455 support for fast loading into the emulated ROM; to debug, you must use
5456 another protocol, such as standard remote protocol. The usual
5457 sequence is something like
5459 target nrom <netrom-hostname>
5461 target remote <netrom-hostname>:1235
5465 GDB now includes support for the Apple Macintosh, as a host only. It
5466 may be run as either an MPW tool or as a standalone application, and
5467 it can debug through the serial port. All the usual GDB commands are
5468 available, but to the target command, you must supply "serial" as the
5469 device type instead of "/dev/ttyXX". See mpw-README in the main
5470 directory for more information on how to build. The MPW configuration
5471 scripts */mpw-config.in support only a few targets, and only the
5472 mips-idt-ecoff target has been tested.
5476 GDB configuration now uses autoconf. This is not user-visible,
5477 but does simplify configuration and building.
5481 GDB now supports hpux10.
5483 *** Changes in GDB-4.14:
5485 * New native configurations
5487 x86 FreeBSD i[345]86-*-freebsd
5488 x86 NetBSD i[345]86-*-netbsd
5489 NS32k NetBSD ns32k-*-netbsd
5490 Sparc NetBSD sparc-*-netbsd
5494 A29K VxWorks a29k-*-vxworks
5495 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5496 CPU32 EST-300 emulator m68*-*-est*
5497 PowerPC ELF powerpc-*-elf
5500 * Alpha OSF/1 support for procfs
5502 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5503 possible to attach to running processes. As the mounting of the /proc
5504 filesystem is optional on the Alpha, GDB automatically determines
5505 the availability of /proc during startup. This can lead to problems
5506 if /proc is unmounted after GDB has been started.
5508 * Arguments to user-defined commands
5510 User commands may accept up to 10 arguments separated by whitespace.
5511 Arguments are accessed within the user command via $arg0..$arg9. A
5514 print $arg0 + $arg1 + $arg2
5516 To execute the command use:
5519 Defines the command "adder" which prints the sum of its three arguments.
5520 Note the arguments are text substitutions, so they may reference variables,
5521 use complex expressions, or even perform inferior function calls.
5523 * New `if' and `while' commands
5525 This makes it possible to write more sophisticated user-defined
5526 commands. Both commands take a single argument, which is the
5527 expression to evaluate, and must be followed by the commands to
5528 execute, one per line, if the expression is nonzero, the list being
5529 terminated by the word `end'. The `if' command list may include an
5530 `else' word, which causes the following commands to be executed only
5531 if the expression is zero.
5533 * Fortran source language mode
5535 GDB now includes partial support for Fortran 77. It will recognize
5536 Fortran programs and can evaluate a subset of Fortran expressions, but
5537 variables and functions may not be handled correctly. GDB will work
5538 with G77, but does not yet know much about symbols emitted by other
5541 * Better HPUX support
5543 Most debugging facilities now work on dynamic executables for HPPAs
5544 running hpux9 or later. You can attach to running dynamically linked
5545 processes, but by default the dynamic libraries will be read-only, so
5546 for instance you won't be able to put breakpoints in them. To change
5547 that behavior do the following before running the program:
5553 This will cause the libraries to be mapped private and read-write.
5554 To revert to the normal behavior, do this:
5560 You cannot set breakpoints or examine data in the library until after
5561 the library is loaded if the function/data symbols do not have
5564 GDB can now also read debug symbols produced by the HP C compiler on
5565 HPPAs (sorry, no C++, Fortran or 68k support).
5567 * Target byte order now dynamically selectable
5569 You can choose which byte order to use with a target system, via the
5570 commands "set endian big" and "set endian little", and you can see the
5571 current setting by using "show endian". You can also give the command
5572 "set endian auto", in which case GDB will use the byte order
5573 associated with the executable. Currently, only embedded MIPS
5574 configurations support dynamic selection of target byte order.
5576 * New DOS host serial code
5578 This version uses DPMI interrupts to handle buffered I/O, so you
5579 no longer need to run asynctsr when debugging boards connected to
5582 *** Changes in GDB-4.13:
5584 * New "complete" command
5586 This lists all the possible completions for the rest of the line, if it
5587 were to be given as a command itself. This is intended for use by emacs.
5589 * Trailing space optional in prompt
5591 "set prompt" no longer adds a space for you after the prompt you set. This
5592 allows you to set a prompt which ends in a space or one that does not.
5594 * Breakpoint hit counts
5596 "info break" now displays a count of the number of times the breakpoint
5597 has been hit. This is especially useful in conjunction with "ignore"; you
5598 can ignore a large number of breakpoint hits, look at the breakpoint info
5599 to see how many times the breakpoint was hit, then run again, ignoring one
5600 less than that number, and this will get you quickly to the last hit of
5603 * Ability to stop printing at NULL character
5605 "set print null-stop" will cause GDB to stop printing the characters of
5606 an array when the first NULL is encountered. This is useful when large
5607 arrays actually contain only short strings.
5609 * Shared library breakpoints
5611 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5612 breakpoints in shared libraries before the executable is run.
5614 * Hardware watchpoints
5616 There is a new hardware breakpoint for the watch command for sparclite
5617 targets. See gdb/sparclite/hw_breakpoint.note.
5619 Hardware watchpoints are also now supported under GNU/Linux.
5623 Annotations have been added. These are for use with graphical interfaces,
5624 and are still experimental. Currently only gdba.el uses these.
5626 * Improved Irix 5 support
5628 GDB now works properly with Irix 5.2.
5630 * Improved HPPA support
5632 GDB now works properly with the latest GCC and GAS.
5634 * New native configurations
5636 Sequent PTX4 i[34]86-sequent-ptx4
5637 HPPA running OSF/1 hppa*-*-osf*
5638 Atari TT running SVR4 m68*-*-sysv4*
5639 RS/6000 LynxOS rs6000-*-lynxos*
5643 OS/9000 i[34]86-*-os9k
5644 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5647 * Hitachi SH7000 and E7000-PC ICE support
5649 There is now support for communicating with the Hitachi E7000-PC ICE.
5650 This is available automatically when GDB is configured for the SH.
5654 As usual, a variety of small fixes and improvements, both generic
5655 and configuration-specific. See the ChangeLog for more detail.
5657 *** Changes in GDB-4.12:
5659 * Irix 5 is now supported
5663 GDB-4.12 on the HPPA has a number of changes which make it unable
5664 to debug the output from the currently released versions of GCC and
5665 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5666 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5667 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5670 *** Changes in GDB-4.11:
5672 * User visible changes:
5676 The "set remotedebug" option is now consistent between the mips remote
5677 target, remote targets using the gdb-specific protocol, UDI (AMD's
5678 debug protocol for the 29k) and the 88k bug monitor. It is now an
5679 integer specifying a debug level (normally 0 or 1, but 2 means more
5680 debugging info for the mips target).
5682 * DEC Alpha native support
5684 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5685 debug info, but GDB works fairly well with the DEC compiler and should
5686 work with a future GCC release. See the README file for a few
5687 Alpha-specific notes.
5689 * Preliminary thread implementation
5691 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5693 * LynxOS native and target support for 386
5695 This release has been hosted on LynxOS 2.2, and also can be configured
5696 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5699 * Improvements in C++ mangling/demangling.
5701 This release has much better g++ debugging, specifically in name
5702 mangling/demangling, virtual function calls, print virtual table,
5703 call methods, ...etc.
5705 *** Changes in GDB-4.10:
5707 * User visible changes:
5709 Remote debugging using the GDB-specific (`target remote') protocol now
5710 supports the `load' command. This is only useful if you have some
5711 other way of getting the stub to the target system, and you can put it
5712 somewhere in memory where it won't get clobbered by the download.
5714 Filename completion now works.
5716 When run under emacs mode, the "info line" command now causes the
5717 arrow to point to the line specified. Also, "info line" prints
5718 addresses in symbolic form (as well as hex).
5720 All vxworks based targets now support a user settable option, called
5721 vxworks-timeout. This option represents the number of seconds gdb
5722 should wait for responses to rpc's. You might want to use this if
5723 your vxworks target is, perhaps, a slow software simulator or happens
5724 to be on the far side of a thin network line.
5728 This release contains support for using a DEC alpha as a GDB host for
5729 cross debugging. Native alpha debugging is not supported yet.
5732 *** Changes in GDB-4.9:
5736 This is the first GDB release which is accompanied by a matching testsuite.
5737 The testsuite requires installation of dejagnu, which should be available
5738 via ftp from most sites that carry GNU software.
5742 'Cfront' style demangling has had its name changed to 'ARM' style, to
5743 emphasize that it was written from the specifications in the C++ Annotated
5744 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5745 disclaimers, it still generated too much confusion with users attempting to
5746 use gdb with AT&T cfront.
5750 GDB now uses a standard remote interface to a simulator library.
5751 So far, the library contains simulators for the Zilog Z8001/2, the
5752 Hitachi H8/300, H8/500 and Super-H.
5754 * New targets supported
5756 H8/300 simulator h8300-hitachi-hms or h8300hms
5757 H8/500 simulator h8500-hitachi-hms or h8500hms
5758 SH simulator sh-hitachi-hms or sh
5759 Z8000 simulator z8k-zilog-none or z8ksim
5760 IDT MIPS board over serial line mips-idt-ecoff
5762 Cross-debugging to GO32 targets is supported. It requires a custom
5763 version of the i386-stub.c module which is integrated with the
5764 GO32 memory extender.
5766 * New remote protocols
5768 MIPS remote debugging protocol.
5770 * New source languages supported
5772 This version includes preliminary support for Chill, a Pascal like language
5773 used by telecommunications companies. Chill support is also being integrated
5774 into the GNU compiler, but we don't know when it will be publically available.
5777 *** Changes in GDB-4.8:
5779 * HP Precision Architecture supported
5781 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5782 version of this support was available as a set of patches from the
5783 University of Utah. GDB does not support debugging of programs
5784 compiled with the HP compiler, because HP will not document their file
5785 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5786 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5788 Many problems in the preliminary version have been fixed.
5790 * Faster and better demangling
5792 We have improved template demangling and fixed numerous bugs in the GNU style
5793 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5794 character types (wchar_t) are now supported. Demangling of each symbol is now
5795 only done once, and is cached when the symbol table for a file is read in.
5796 This results in a small increase in memory usage for C programs, a moderate
5797 increase in memory usage for C++ programs, and a fantastic speedup in
5800 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5801 from the specifications in the Annotated Reference Manual, which AT&T's
5802 compiler does not actually implement.
5804 * G++ multiple inheritance compiler problem
5806 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5807 inheritance lattices was reworked to properly discover ambiguities. We
5808 recently found an example which causes this new algorithm to fail in a
5809 very subtle way, producing bad debug information for those classes.
5810 The file 'gcc.patch' (in this directory) can be applied to gcc to
5811 circumvent the problem. A future GCC release will contain a complete
5814 The previous G++ debug info problem (mentioned below for the gdb-4.7
5815 release) is fixed in gcc version 2.3.2.
5817 * Improved configure script
5819 The `configure' script will now attempt to guess your system type if
5820 you don't supply a host system type. The old scheme of supplying a
5821 host system triplet is preferable over using this. All the magic is
5822 done in the new `config.guess' script. Examine it for details.
5824 We have also brought our configure script much more in line with the FSF's
5825 version. It now supports the --with-xxx options. In particular,
5826 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5827 The resulting GDB will not be able to read arbitrary object file formats --
5828 only the format ``expected'' to be used on the configured target system.
5829 We hope to make this the default in a future release.
5831 * Documentation improvements
5833 There's new internal documentation on how to modify GDB, and how to
5834 produce clean changes to the code. We implore people to read it
5835 before submitting changes.
5837 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5838 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5839 `info' files are also provided. To build `info' files from scratch,
5840 you will need the latest `makeinfo' release, which will be available in
5841 a future texinfo-X.Y release.
5843 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5844 We're not sure exactly which versions have this problem, but it has
5845 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5846 or better. If that isn't possible, there is a patch in
5847 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5848 around this problem.
5852 GDB now supports array constants that can be used in expressions typed in by
5853 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5854 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5857 The new directory `gdb/sparclite' contains a program that demonstrates
5858 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5860 * New native hosts supported
5862 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5863 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5865 * New targets supported
5867 AMD 29k family via UDI a29k-amd-udi or udi29k
5869 * New file formats supported
5871 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5872 HPUX core files, and SCO 3.2v2 core files.
5876 Attaching to processes now works again; thanks for the many bug reports.
5878 We have also stomped on a bunch of core dumps caused by
5879 printf_filtered("%s") problems.
5881 We eliminated a copyright problem on the rpc and ptrace header files
5882 for VxWorks, which was discovered at the last minute during the 4.7
5883 release. You should now be able to build a VxWorks GDB.
5885 You can now interrupt gdb while an attached process is running. This
5886 will cause the attached process to stop, and give control back to GDB.
5888 We fixed problems caused by using too many file descriptors
5889 for reading symbols from object files and libraries. This was
5890 especially a problem for programs that used many (~100) shared
5893 The `step' command now only enters a subroutine if there is line number
5894 information for the subroutine. Otherwise it acts like the `next'
5895 command. Previously, `step' would enter subroutines if there was
5896 any debugging information about the routine. This avoids problems
5897 when using `cc -g1' on MIPS machines.
5899 * Internal improvements
5901 GDB's internal interfaces have been improved to make it easier to support
5902 debugging of multiple languages in the future.
5904 GDB now uses a common structure for symbol information internally.
5905 Minimal symbols (derived from linkage symbols in object files), partial
5906 symbols (from a quick scan of debug information), and full symbols
5907 contain a common subset of information, making it easier to write
5908 shared code that handles any of them.
5910 * New command line options
5912 We now accept --silent as an alias for --quiet.
5916 The memory-mapped-malloc library is now licensed under the GNU Library
5917 General Public License.
5919 *** Changes in GDB-4.7:
5921 * Host/native/target split
5923 GDB has had some major internal surgery to untangle the support for
5924 hosts and remote targets. Now, when you configure GDB for a remote
5925 target, it will no longer load in all of the support for debugging
5926 local programs on the host. When fully completed and tested, this will
5927 ensure that arbitrary host/target combinations are possible.
5929 The primary conceptual shift is to separate the non-portable code in
5930 GDB into three categories. Host specific code is required any time GDB
5931 is compiled on that host, regardless of the target. Target specific
5932 code relates to the peculiarities of the target, but can be compiled on
5933 any host. Native specific code is everything else: it can only be
5934 built when the host and target are the same system. Child process
5935 handling and core file support are two common `native' examples.
5937 GDB's use of /proc for controlling Unix child processes is now cleaner.
5938 It has been split out into a single module under the `target_ops' vector,
5939 plus two native-dependent functions for each system that uses /proc.
5941 * New hosts supported
5943 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5944 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5945 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5947 * New targets supported
5949 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5950 68030 and CPU32 m68030-*-*, m68332-*-*
5952 * New native hosts supported
5954 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5955 (386bsd is not well tested yet)
5956 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5958 * New file formats supported
5960 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5961 supports reading of `a.out.adobe' object files, which are an a.out
5962 format extended with minimal information about multiple sections.
5966 `show copying' is the same as the old `info copying'.
5967 `show warranty' is the same as `info warrantee'.
5968 These were renamed for consistency. The old commands continue to work.
5970 `info handle' is a new alias for `info signals'.
5972 You can now define pre-command hooks, which attach arbitrary command
5973 scripts to any command. The commands in the hook will be executed
5974 prior to the user's command. You can also create a hook which will be
5975 executed whenever the program stops. See gdb.texinfo.
5979 We now deal with Cfront style name mangling, and can even extract type
5980 info from mangled symbols. GDB can automatically figure out which
5981 symbol mangling style your C++ compiler uses.
5983 Calling of methods and virtual functions has been improved as well.
5987 The crash that occured when debugging Sun Ansi-C compiled binaries is
5988 fixed. This was due to mishandling of the extra N_SO stabs output
5991 We also finally got Ultrix 4.2 running in house, and fixed core file
5992 support, with help from a dozen people on the net.
5994 John M. Farrell discovered that the reason that single-stepping was so
5995 slow on all of the Mips based platforms (primarily SGI and DEC) was
5996 that we were trying to demangle and lookup a symbol used for internal
5997 purposes on every instruction that was being stepped through. Changing
5998 the name of that symbol so that it couldn't be mistaken for a C++
5999 mangled symbol sped things up a great deal.
6001 Rich Pixley sped up symbol lookups in general by getting much smarter
6002 about when C++ symbol mangling is necessary. This should make symbol
6003 completion (TAB on the command line) much faster. It's not as fast as
6004 we'd like, but it's significantly faster than gdb-4.6.
6008 A new user controllable variable 'call_scratch_address' can
6009 specify the location of a scratch area to be used when GDB
6010 calls a function in the target. This is necessary because the
6011 usual method of putting the scratch area on the stack does not work
6012 in systems that have separate instruction and data spaces.
6014 We integrated changes to support the 29k UDI (Universal Debugger
6015 Interface), but discovered at the last minute that we didn't have all
6016 of the appropriate copyright paperwork. We are working with AMD to
6017 resolve this, and hope to have it available soon.
6021 We have sped up the remote serial line protocol, especially for targets
6022 with lots of registers. It now supports a new `expedited status' ('T')
6023 message which can be used in place of the existing 'S' status message.
6024 This allows the remote stub to send only the registers that GDB
6025 needs to make a quick decision about single-stepping or conditional
6026 breakpoints, eliminating the need to fetch the entire register set for
6027 each instruction being stepped through.
6029 The GDB remote serial protocol now implements a write-through cache for
6030 registers, only re-reading the registers if the target has run.
6032 There is also a new remote serial stub for SPARC processors. You can
6033 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6034 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6035 processor with a serial port.
6039 Configure.in files have become much easier to read and modify. A new
6040 `table driven' format makes it more obvious what configurations are
6041 supported, and what files each one uses.
6045 There is a new opcodes library which will eventually contain all of the
6046 disassembly routines and opcode tables. At present, it only contains
6047 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6048 disassembler (binutils/objdump) to share these routines.
6050 The libiberty library is now copylefted under the GNU Library General
6051 Public License. This allows more liberal use, and was done so libg++
6052 can use it. This makes no difference to GDB, since the Library License
6053 grants all the rights from the General Public License.
6057 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6058 reference to the stabs symbol info used by the debugger. It is (as far
6059 as we know) the only published document on this fascinating topic. We
6060 encourage you to read it, compare it to the stabs information on your
6061 system, and send improvements on the document in general (to
6062 bug-gdb@prep.ai.mit.edu).
6064 And, of course, many bugs have been fixed.
6067 *** Changes in GDB-4.6:
6069 * Better support for C++ function names
6071 GDB now accepts as input the "demangled form" of C++ overloaded function
6072 names and member function names, and can do command completion on such names
6073 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6074 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6075 Make use of command completion, it is your friend.
6077 GDB also now accepts a variety of C++ mangled symbol formats. They are
6078 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6079 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6080 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6081 for the list of formats.
6083 * G++ symbol mangling problem
6085 Recent versions of gcc have a bug in how they emit debugging information for
6086 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6087 directory) can be applied to gcc to fix the problem. Alternatively, if you
6088 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6089 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6090 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6093 * New 'maintenance' command
6095 All of the commands related to hacking GDB internals have been moved out of
6096 the main command set, and now live behind the 'maintenance' command. This
6097 can also be abbreviated as 'mt'. The following changes were made:
6099 dump-me -> maintenance dump-me
6100 info all-breakpoints -> maintenance info breakpoints
6101 printmsyms -> maintenance print msyms
6102 printobjfiles -> maintenance print objfiles
6103 printpsyms -> maintenance print psymbols
6104 printsyms -> maintenance print symbols
6106 The following commands are new:
6108 maintenance demangle Call internal GDB demangler routine to
6109 demangle a C++ link name and prints the result.
6110 maintenance print type Print a type chain for a given symbol
6112 * Change to .gdbinit file processing
6114 We now read the $HOME/.gdbinit file before processing the argv arguments
6115 (e.g. reading symbol files or core files). This allows global parameters to
6116 be set, which will apply during the symbol reading. The ./.gdbinit is still
6117 read after argv processing.
6119 * New hosts supported
6121 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6123 GNU/Linux support i386-unknown-linux or linux
6125 We are also including code to support the HP/PA running BSD and HPUX. This
6126 is almost guaranteed not to work, as we didn't have time to test or build it
6127 for this release. We are including it so that the more adventurous (or
6128 masochistic) of you can play with it. We also had major problems with the
6129 fact that the compiler that we got from HP doesn't support the -g option.
6132 * New targets supported
6134 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6136 * More smarts about finding #include files
6138 GDB now remembers the compilation directory for all include files, and for
6139 all files from which C is generated (like yacc and lex sources). This
6140 greatly improves GDB's ability to find yacc/lex sources, and include files,
6141 especially if you are debugging your program from a directory different from
6142 the one that contains your sources.
6144 We also fixed a bug which caused difficulty with listing and setting
6145 breakpoints in include files which contain C code. (In the past, you had to
6146 try twice in order to list an include file that you hadn't looked at before.)
6148 * Interesting infernals change
6150 GDB now deals with arbitrary numbers of sections, where the symbols for each
6151 section must be relocated relative to that section's landing place in the
6152 target's address space. This work was needed to support ELF with embedded
6153 stabs used by Solaris-2.0.
6155 * Bug fixes (of course!)
6157 There have been loads of fixes for the following things:
6158 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6159 i960, stabs, DOS(GO32), procfs, etc...
6161 See the ChangeLog for details.
6163 *** Changes in GDB-4.5:
6165 * New machines supported (host and target)
6167 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6169 SGI Irix-4.x mips-sgi-irix4 or iris4
6171 * New malloc package
6173 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6174 Mmalloc is capable of handling mutiple heaps of memory. It is also
6175 capable of saving a heap to a file, and then mapping it back in later.
6176 This can be used to greatly speedup the startup of GDB by using a
6177 pre-parsed symbol table which lives in a mmalloc managed heap. For
6178 more details, please read mmalloc/mmalloc.texi.
6182 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6183 'help info proc' for details.
6185 * MIPS ecoff symbol table format
6187 The code that reads MIPS symbol table format is now supported on all hosts.
6188 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6191 * File name changes for MS-DOS
6193 Many files in the config directories have been renamed to make it easier to
6194 support GDB on MS-DOSe systems (which have very restrictive file name
6195 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6196 environment) is close to working but has some remaining problems. Note
6197 that debugging of DOS programs is not supported, due to limitations
6198 in the ``operating system'', but it can be used to host cross-debugging.
6200 * Cross byte order fixes
6202 Many fixes have been made to support cross debugging of Sparc and MIPS
6203 targets from hosts whose byte order differs.
6205 * New -mapped and -readnow options
6207 If memory-mapped files are available on your system through the 'mmap'
6208 system call, you can use the -mapped option on the `file' or
6209 `symbol-file' commands to cause GDB to write the symbols from your
6210 program into a reusable file. If the program you are debugging is
6211 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6212 Future GDB debugging sessions will notice the presence of this file,
6213 and will quickly map in symbol information from it, rather than reading
6214 the symbol table from the executable program. Using the '-mapped'
6215 option in a GDB `file' or `symbol-file' command has the same effect as
6216 starting GDB with the '-mapped' command-line option.
6218 You can cause GDB to read the entire symbol table immediately by using
6219 the '-readnow' option with any of the commands that load symbol table
6220 information (or on the GDB command line). This makes the command
6221 slower, but makes future operations faster.
6223 The -mapped and -readnow options are typically combined in order to
6224 build a `fred.syms' file that contains complete symbol information.
6225 A simple GDB invocation to do nothing but build a `.syms' file for future
6228 gdb -batch -nx -mapped -readnow programname
6230 The `.syms' file is specific to the host machine on which GDB is run.
6231 It holds an exact image of GDB's internal symbol table. It cannot be
6232 shared across multiple host platforms.
6234 * longjmp() handling
6236 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6237 siglongjmp() without losing control. This feature has not yet been ported to
6238 all systems. It currently works on many 386 platforms, all MIPS-based
6239 platforms (SGI, DECstation, etc), and Sun3/4.
6243 Preliminary work has been put in to support the new Solaris OS from Sun. At
6244 this time, it can control and debug processes, but it is not capable of
6249 As always, many many bug fixes. The major areas were with g++, and mipsread.
6250 People using the MIPS-based platforms should experience fewer mysterious
6251 crashes and trashed symbol tables.
6253 *** Changes in GDB-4.4:
6255 * New machines supported (host and target)
6257 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6259 BSD Reno on Vax vax-dec-bsd
6260 Ultrix on Vax vax-dec-ultrix
6262 * New machines supported (target)
6264 AMD 29000 embedded, using EBMON a29k-none-none
6268 GDB continues to improve its handling of C++. `References' work better.
6269 The demangler has also been improved, and now deals with symbols mangled as
6270 per the Annotated C++ Reference Guide.
6272 GDB also now handles `stabs' symbol information embedded in MIPS
6273 `ecoff' symbol tables. Since the ecoff format was not easily
6274 extensible to handle new languages such as C++, this appeared to be a
6275 good way to put C++ debugging info into MIPS binaries. This option
6276 will be supported in the GNU C compiler, version 2, when it is
6279 * New features for SVR4
6281 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6282 shared libraries. Debugging dynamically linked programs should present
6283 only minor differences from debugging statically linked programs.
6285 The `info proc' command will print out information about any process
6286 on an SVR4 system (including the one you are debugging). At the moment,
6287 it prints the address mappings of the process.
6289 If you bring up GDB on another SVR4 system, please send mail to
6290 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6292 * Better dynamic linking support in SunOS
6294 Reading symbols from shared libraries which contain debugging symbols
6295 now works properly. However, there remain issues such as automatic
6296 skipping of `transfer vector' code during function calls, which
6297 make it harder to debug code in a shared library, than to debug the
6298 same code linked statically.
6302 GDB is now using the latest `getopt' routines from the FSF. This
6303 version accepts the -- prefix for options with long names. GDB will
6304 continue to accept the old forms (-option and +option) as well.
6305 Various single letter abbreviations for options have been explicity
6306 added to the option table so that they won't get overshadowed in the
6307 future by other options that begin with the same letter.
6311 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6312 Many assorted bugs have been handled. Many more remain to be handled.
6313 See the various ChangeLog files (primarily in gdb and bfd) for details.
6316 *** Changes in GDB-4.3:
6318 * New machines supported (host and target)
6320 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6321 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6322 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6324 * Almost SCO Unix support
6326 We had hoped to support:
6327 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6328 (except for core file support), but we discovered very late in the release
6329 that it has problems with process groups that render gdb unusable. Sorry
6330 about that. I encourage people to fix it and post the fixes.
6332 * Preliminary ELF and DWARF support
6334 GDB can read ELF object files on System V Release 4, and can handle
6335 debugging records for C, in DWARF format, in ELF files. This support
6336 is preliminary. If you bring up GDB on another SVR4 system, please
6337 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6342 GDB now uses the latest `readline' library. One user-visible change
6343 is that two tabs will list possible command completions, which previously
6344 required typing M-? (meta-question mark, or ESC ?).
6348 The `stepi' bug that many of you noticed has been squashed.
6349 Many bugs in C++ have been handled. Many more remain to be handled.
6350 See the various ChangeLog files (primarily in gdb and bfd) for details.
6352 * State of the MIPS world (in case you wondered):
6354 GDB can understand the symbol tables emitted by the compilers
6355 supplied by most vendors of MIPS-based machines, including DEC. These
6356 symbol tables are in a format that essentially nobody else uses.
6358 Some versions of gcc come with an assembler post-processor called
6359 mips-tfile. This program is required if you want to do source-level
6360 debugging of gcc-compiled programs. I believe FSF does not ship
6361 mips-tfile with gcc version 1, but it will eventually come with gcc
6364 Debugging of g++ output remains a problem. g++ version 1.xx does not
6365 really support it at all. (If you're lucky, you should be able to get
6366 line numbers and stack traces to work, but no parameters or local
6367 variables.) With some work it should be possible to improve the
6370 When gcc version 2 is released, you will have somewhat better luck.
6371 However, even then you will get confusing results for inheritance and
6374 We will eventually provide full debugging of g++ output on
6375 DECstations. This will probably involve some kind of stabs-in-ecoff
6376 encapulation, but the details have not been worked out yet.
6379 *** Changes in GDB-4.2:
6381 * Improved configuration
6383 Only one copy of `configure' exists now, and it is not self-modifying.
6384 Porting BFD is simpler.
6388 The `step' and `next' commands now only stop at the first instruction
6389 of a source line. This prevents the multiple stops that used to occur
6390 in switch statements, for-loops, etc. `Step' continues to stop if a
6391 function that has debugging information is called within the line.
6395 Lots of small bugs fixed. More remain.
6397 * New host supported (not target)
6399 Intel 386 PC clone running Mach i386-none-mach
6402 *** Changes in GDB-4.1:
6404 * Multiple source language support
6406 GDB now has internal scaffolding to handle several source languages.
6407 It determines the type of each source file from its filename extension,
6408 and will switch expression parsing and number formatting to match the
6409 language of the function in the currently selected stack frame.
6410 You can also specifically set the language to be used, with
6411 `set language c' or `set language modula-2'.
6415 GDB now has preliminary support for the GNU Modula-2 compiler,
6416 currently under development at the State University of New York at
6417 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6418 continue through the fall of 1991 and into 1992.
6420 Other Modula-2 compilers are currently not supported, and attempting to
6421 debug programs compiled with them will likely result in an error as the
6422 symbol table is read. Feel free to work on it, though!
6424 There are hooks in GDB for strict type checking and range checking,
6425 in the `Modula-2 philosophy', but they do not currently work.
6429 GDB can now write to executable and core files (e.g. patch
6430 a variable's value). You must turn this switch on, specify
6431 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6432 by assigning a new value to a variable. Modifications take
6435 * Automatic SunOS shared library reading
6437 When you run your program, GDB automatically determines where its
6438 shared libraries (if any) have been loaded, and reads their symbols.
6439 The `share' command is no longer needed. This also works when
6440 examining core files.
6444 You can specify the number of lines that the `list' command shows.
6447 * New machines supported (host and target)
6449 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6450 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6451 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6453 * New hosts supported (not targets)
6455 IBM RT/PC: romp-ibm-aix or rtpc
6457 * New targets supported (not hosts)
6459 AMD 29000 embedded with COFF a29k-none-coff
6460 AMD 29000 embedded with a.out a29k-none-aout
6461 Ultracomputer remote kernel debug a29k-nyu-kern
6463 * New remote interfaces
6469 *** Changes in GDB-4.0:
6473 Wide output is wrapped at good places to make the output more readable.
6475 Gdb now supports cross-debugging from a host machine of one type to a
6476 target machine of another type. Communication with the target system
6477 is over serial lines. The ``target'' command handles connecting to the
6478 remote system; the ``load'' command will download a program into the
6479 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6480 also supports debugging of realtime processes running under VxWorks,
6481 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6482 stub on the target system.
6484 New CPUs supported include the AMD 29000 and Intel 960.
6486 GDB now reads object files and symbol tables via a ``binary file''
6487 library, which allows a single copy of GDB to debug programs of multiple
6488 object file types such as a.out and coff.
6490 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6491 refcard.dvi and refcard.ps are available to format it).
6494 * Control-Variable user interface simplified
6496 All variables that control the operation of the debugger can be set
6497 by the ``set'' command, and displayed by the ``show'' command.
6499 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6500 ``Show prompt'' produces the response:
6501 Gdb's prompt is new-gdb=>.
6503 What follows are the NEW set commands. The command ``help set'' will
6504 print a complete list of old and new set commands. ``help set FOO''
6505 will give a longer description of the variable FOO. ``show'' will show
6506 all of the variable descriptions and their current settings.
6508 confirm on/off: Enables warning questions for operations that are
6509 hard to recover from, e.g. rerunning the program while
6510 it is already running. Default is ON.
6512 editing on/off: Enables EMACS style command line editing
6513 of input. Previous lines can be recalled with
6514 control-P, the current line can be edited with control-B,
6515 you can search for commands with control-R, etc.
6518 history filename NAME: NAME is where the gdb command history
6519 will be stored. The default is .gdb_history,
6520 or the value of the environment variable
6523 history size N: The size, in commands, of the command history. The
6524 default is 256, or the value of the environment variable
6527 history save on/off: If this value is set to ON, the history file will
6528 be saved after exiting gdb. If set to OFF, the
6529 file will not be saved. The default is OFF.
6531 history expansion on/off: If this value is set to ON, then csh-like
6532 history expansion will be performed on
6533 command line input. The default is OFF.
6535 radix N: Sets the default radix for input and output. It can be set
6536 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6537 in the current radix, so "set radix 10" is always a no-op.
6539 height N: This integer value is the number of lines on a page. Default
6540 is 24, the current `stty rows'' setting, or the ``li#''
6541 setting from the termcap entry matching the environment
6544 width N: This integer value is the number of characters on a line.
6545 Default is 80, the current `stty cols'' setting, or the ``co#''
6546 setting from the termcap entry matching the environment
6549 Note: ``set screensize'' is obsolete. Use ``set height'' and
6550 ``set width'' instead.
6552 print address on/off: Print memory addresses in various command displays,
6553 such as stack traces and structure values. Gdb looks
6554 more ``symbolic'' if you turn this off; it looks more
6555 ``machine level'' with it on. Default is ON.
6557 print array on/off: Prettyprint arrays. New convenient format! Default
6560 print demangle on/off: Print C++ symbols in "source" form if on,
6563 print asm-demangle on/off: Same, for assembler level printouts
6566 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6569 * Support for Epoch Environment.
6571 The epoch environment is a version of Emacs v18 with windowing. One
6572 new command, ``inspect'', is identical to ``print'', except that if you
6573 are running in the epoch environment, the value is printed in its own
6577 * Support for Shared Libraries
6579 GDB can now debug programs and core files that use SunOS shared libraries.
6580 Symbols from a shared library cannot be referenced
6581 before the shared library has been linked with the program (this
6582 happens after you type ``run'' and before the function main() is entered).
6583 At any time after this linking (including when examining core files
6584 from dynamically linked programs), gdb reads the symbols from each
6585 shared library when you type the ``sharedlibrary'' command.
6586 It can be abbreviated ``share''.
6588 sharedlibrary REGEXP: Load shared object library symbols for files
6589 matching a unix regular expression. No argument
6590 indicates to load symbols for all shared libraries.
6592 info sharedlibrary: Status of loaded shared libraries.
6597 A watchpoint stops execution of a program whenever the value of an
6598 expression changes. Checking for this slows down execution
6599 tremendously whenever you are in the scope of the expression, but is
6600 quite useful for catching tough ``bit-spreader'' or pointer misuse
6601 problems. Some machines such as the 386 have hardware for doing this
6602 more quickly, and future versions of gdb will use this hardware.
6604 watch EXP: Set a watchpoint (breakpoint) for an expression.
6606 info watchpoints: Information about your watchpoints.
6608 delete N: Deletes watchpoint number N (same as breakpoints).
6609 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6610 enable N: Re-enables watchpoint number N (same as breakpoints).
6613 * C++ multiple inheritance
6615 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6618 * C++ exception handling
6620 Gdb now supports limited C++ exception handling. Besides the existing
6621 ability to breakpoint on an exception handler, gdb can breakpoint on
6622 the raising of an exception (before the stack is peeled back to the
6625 catch FOO: If there is a FOO exception handler in the dynamic scope,
6626 set a breakpoint to catch exceptions which may be raised there.
6627 Multiple exceptions (``catch foo bar baz'') may be caught.
6629 info catch: Lists all exceptions which may be caught in the
6630 current stack frame.
6633 * Minor command changes
6635 The command ``call func (arg, arg, ...)'' now acts like the print
6636 command, except it does not print or save a value if the function's result
6637 is void. This is similar to dbx usage.
6639 The ``up'' and ``down'' commands now always print the frame they end up
6640 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6641 frames without printing.
6643 * New directory command
6645 'dir' now adds directories to the FRONT of the source search path.
6646 The path starts off empty. Source files that contain debug information
6647 about the directory in which they were compiled can be found even
6648 with an empty path; Sun CC and GCC include this information. If GDB can't
6649 find your source file in the current directory, type "dir .".
6651 * Configuring GDB for compilation
6653 For normal use, type ``./configure host''. See README or gdb.texinfo
6656 GDB now handles cross debugging. If you are remotely debugging between
6657 two different machines, type ``./configure host -target=targ''.
6658 Host is the machine where GDB will run; targ is the machine
6659 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob