1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.12
6 *** Changes in GDB 7.12
8 * GDBserver now supports recording btrace without maintaining an active
11 * GDB now supports a negative repeat count in the 'x' command to examine
12 memory backward from the given address. For example:
15 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
16 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
17 (gdb) x/-5i 0x0000000000400580
18 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
19 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
20 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
21 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
22 0x40057b <main(int, char**)+25>:
23 callq 0x400536 <Func1(int, char const*)>
25 * Fortran: Support structures with fields of dynamic types and
26 arrays of dynamic types.
28 * GDB now supports multibit bitfields and enums in target register
31 * New Python-based convenience function $_as_string(val), which returns
32 the textual representation of a value. This function is especially
33 useful to obtain the text label of an enum value.
35 * Intel MPX bound violation handling.
37 Segmentation faults caused by a Intel MPX boundary violation
38 now display the kind of violation (upper or lower), the memory
39 address accessed and the memory bounds, along with the usual
40 signal received and code location.
44 Program received signal SIGSEGV, Segmentation fault
45 Upper bound violation while accessing address 0x7fffffffc3b3
46 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
47 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
49 * Rust language support.
50 GDB now supports debugging programs written in the Rust programming
51 language. See https://www.rust-lang.org/ for more information about
54 * Support for running interpreters on specified input/output devices
56 GDB now supports a new mechanism that allows frontends to provide
57 fully featured GDB console views, as a better alternative to
58 building such views on top of the "-interpreter-exec console"
59 command. See the new "new-ui" command below. With that command,
60 frontends can now start GDB in the traditional command-line mode
61 running in an embedded terminal emulator widget, and create a
62 separate MI interpreter running on a specified i/o device. In this
63 way, GDB handles line editing, history, tab completion, etc. in the
64 console all by itself, and the GUI uses the separate MI interpreter
65 for its own control and synchronization, invisible to the command
68 * The "catch syscall" command catches groups of related syscalls.
70 The "catch syscall" command now supports catching a group of related
71 syscalls using the 'group:' or 'g:' prefix.
76 skip -gfile file-glob-pattern
77 skip -function function
78 skip -rfunction regular-expression
79 A generalized form of the skip command, with new support for
80 glob-style file names and regular expressions for function names.
81 Additionally, a file spec and a function spec may now be combined.
83 maint info line-table REGEXP
84 Display the contents of GDB's internal line table data struture.
87 Run any GDB unit tests that were compiled in.
90 Start a new user interface instance running INTERP as interpreter,
91 using the TTY file for input/output.
95 ** gdb.Breakpoint objects have a new attribute "pending", which
96 indicates whether the breakpoint is pending.
97 ** Three new breakpoint-related events have been added:
98 gdb.breakpoint_created, gdb.breakpoint_modified, and
99 gdb.breakpoint_deleted.
102 Signal ("set") the given MS-Windows event object. This is used in
103 conjunction with the Windows JIT debugging (AeDebug) support, where
104 the OS suspends a crashing process until a debugger can attach to
105 it. Resuming the crashing process, in order to debug it, is done by
108 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
109 was added in GDBserver, including JIT compiling fast tracepoint's
110 conditional expression bytecode into native code.
112 * Support for various remote target protocols and ROM monitors has
115 target m32rsdi Remote M32R debugging over SDI
116 target mips MIPS remote debugging protocol
117 target pmon PMON ROM monitor
118 target ddb NEC's DDB variant of PMON for Vr4300
119 target rockhopper NEC RockHopper variant of PMON
120 target lsi LSI variant of PMO
122 * Support for tracepoints and fast tracepoints on powerpc-linux,
123 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
124 including JIT compiling fast tracepoint's conditional expression
125 bytecode into native code.
127 * MI async record =record-started now includes the method and format used for
128 recording. For example:
130 =record-started,thread-group="i1",method="btrace",format="bts"
134 Andes NDS32 nds32*-*-elf
136 *** Changes in GDB 7.11
138 * GDB now supports debugging kernel-based threads on FreeBSD.
140 * Per-inferior thread numbers
142 Thread numbers are now per inferior instead of global. If you're
143 debugging multiple inferiors, GDB displays thread IDs using a
144 qualified INF_NUM.THR_NUM form. For example:
148 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
149 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
150 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
151 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
153 As consequence, thread numbers as visible in the $_thread
154 convenience variable and in Python's InferiorThread.num attribute
155 are no longer unique between inferiors.
157 GDB now maintains a second thread ID per thread, referred to as the
158 global thread ID, which is the new equivalent of thread numbers in
159 previous releases. See also $_gthread below.
161 For backwards compatibility, MI's thread IDs always refer to global
164 * Commands that accept thread IDs now accept the qualified
165 INF_NUM.THR_NUM form as well. For example:
168 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
171 * In commands that accept a list of thread IDs, you can now refer to
172 all threads of an inferior using a star wildcard. GDB accepts
173 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
174 refer to all threads of the current inferior. For example, "info
177 * You can use "info threads -gid" to display the global thread ID of
180 * The new convenience variable $_gthread holds the global number of
183 * The new convenience variable $_inferior holds the number of the
186 * GDB now displays the ID and name of the thread that hit a breakpoint
187 or received a signal, if your program is multi-threaded. For
190 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
191 Thread 1 "main" received signal SIGINT, Interrupt.
193 * Record btrace now supports non-stop mode.
195 * Support for tracepoints on aarch64-linux was added in GDBserver.
197 * The 'record instruction-history' command now indicates speculative execution
198 when using the Intel Processor Trace recording format.
200 * GDB now allows users to specify explicit locations, bypassing
201 the linespec parser. This feature is also available to GDB/MI
204 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
205 GDB now is able to debug both AArch64 applications and ARM applications
208 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
209 including JIT compiling fast tracepoint's conditional expression bytecode
212 * GDB now supports displaced stepping on AArch64 GNU/Linux.
214 * "info threads", "info inferiors", "info display", "info checkpoints"
215 and "maint info program-spaces" now list the corresponding items in
216 ascending ID order, for consistency with all other "info" commands.
218 * In Ada, the overloads selection menu has been enhanced to display the
219 parameter types and the return types for the matching overloaded subprograms.
223 maint set target-non-stop (on|off|auto)
224 maint show target-non-stop
225 Control whether GDB targets always operate in non-stop mode even if
226 "set non-stop" is "off". The default is "auto", meaning non-stop
227 mode is enabled if supported by the target.
229 maint set bfd-sharing
230 maint show bfd-sharing
231 Control the reuse of bfd objects.
235 Control display of debugging info regarding bfd caching.
239 Control display of debugging info regarding FreeBSD threads.
241 set remote multiprocess-extensions-packet
242 show remote multiprocess-extensions-packet
243 Set/show the use of the remote protocol multiprocess extensions.
245 set remote thread-events
246 show remote thread-events
247 Set/show the use of thread create/exit events.
249 set ada print-signatures on|off
250 show ada print-signatures"
251 Control whether parameter types and return types are displayed in overloads
252 selection menus. It is activaled (@code{on}) by default.
256 Controls the maximum size of memory, in bytes, that GDB will
257 allocate for value contents. Prevents incorrect programs from
258 causing GDB to allocate overly large buffers. Default is 64k.
260 * The "disassemble" command accepts a new modifier: /s.
261 It prints mixed source+disassembly like /m with two differences:
262 - disassembled instructions are now printed in program order, and
263 - and source for all relevant files is now printed.
264 The "/m" option is now considered deprecated: its "source-centric"
265 output hasn't proved useful in practice.
267 * The "record instruction-history" command accepts a new modifier: /s.
268 It behaves exactly like /m and prints mixed source+disassembly.
270 * The "set scheduler-locking" command supports a new mode "replay".
271 It behaves like "off" in record mode and like "on" in replay mode.
273 * Support for various ROM monitors has been removed:
275 target dbug dBUG ROM monitor for Motorola ColdFire
276 target picobug Motorola picobug monitor
277 target dink32 DINK32 ROM monitor for PowerPC
278 target m32r Renesas M32R/D ROM monitor
279 target mon2000 mon2000 ROM monitor
280 target ppcbug PPCBUG ROM monitor for PowerPC
282 * Support for reading/writing memory and extracting values on architectures
283 whose memory is addressable in units of any integral multiple of 8 bits.
288 Indicates that an exec system call was executed.
290 exec-events feature in qSupported
291 The qSupported packet allows GDB to request support for exec
292 events using the new 'gdbfeature' exec-event, and the qSupported
293 response can contain the corresponding 'stubfeature'. Set and
294 show commands can be used to display whether these features are enabled.
297 Equivalent to interrupting with the ^C character, but works in
300 thread created stop reason (T05 create:...)
301 Indicates that the thread was just created and is stopped at entry.
303 thread exit stop reply (w exitcode;tid)
304 Indicates that the thread has terminated.
307 Enables/disables thread create and exit event reporting. For
308 example, this is used in non-stop mode when GDB stops a set of
309 threads and synchronously waits for the their corresponding stop
310 replies. Without exit events, if one of the threads exits, GDB
311 would hang forever not knowing that it should no longer expect a
312 stop for that same thread.
315 Indicates that there are no resumed threads left in the target (all
316 threads are stopped). The remote stub reports support for this stop
317 reply to GDB's qSupported query.
320 Enables/disables catching syscalls from the inferior process.
321 The remote stub reports support for this packet to GDB's qSupported query.
323 syscall_entry stop reason
324 Indicates that a syscall was just called.
326 syscall_return stop reason
327 Indicates that a syscall just returned.
329 * Extended-remote exec events
331 ** GDB now has support for exec events on extended-remote Linux targets.
332 For such targets with Linux kernels 2.5.46 and later, this enables
333 follow-exec-mode and exec catchpoints.
335 set remote exec-event-feature-packet
336 show remote exec-event-feature-packet
337 Set/show the use of the remote exec event feature.
339 * Thread names in remote protocol
341 The reply to qXfer:threads:read may now include a name attribute for each
344 * Target remote mode fork and exec events
346 ** GDB now has support for fork and exec events on target remote mode
347 Linux targets. For such targets with Linux kernels 2.5.46 and later,
348 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
349 fork and exec catchpoints.
351 * Remote syscall events
353 ** GDB now has support for catch syscall on remote Linux targets,
354 currently enabled on x86/x86_64 architectures.
356 set remote catch-syscall-packet
357 show remote catch-syscall-packet
358 Set/show the use of the remote catch syscall feature.
362 ** The -var-set-format command now accepts the zero-hexadecimal
363 format. It outputs data in hexadecimal format with zero-padding on the
368 ** gdb.InferiorThread objects have a new attribute "global_num",
369 which refers to the thread's global thread ID. The existing
370 "num" attribute now refers to the thread's per-inferior number.
371 See "Per-inferior thread numbers" above.
372 ** gdb.InferiorThread objects have a new attribute "inferior", which
373 is the Inferior object the thread belongs to.
375 *** Changes in GDB 7.10
377 * Support for process record-replay and reverse debugging on aarch64*-linux*
378 targets has been added. GDB now supports recording of A64 instruction set
379 including advance SIMD instructions.
381 * Support for Sun's version of the "stabs" debug file format has been removed.
383 * GDB now honors the content of the file /proc/PID/coredump_filter
384 (PID is the process ID) on GNU/Linux systems. This file can be used
385 to specify the types of memory mappings that will be included in a
386 corefile. For more information, please refer to the manual page of
387 "core(5)". GDB also has a new command: "set use-coredump-filter
388 on|off". It allows to set whether GDB will read the content of the
389 /proc/PID/coredump_filter file when generating a corefile.
391 * The "info os" command on GNU/Linux can now display information on
393 "info os cpus" Listing of all cpus/cores on the system
395 * GDB has two new commands: "set serial parity odd|even|none" and
396 "show serial parity". These allows to set or show parity for the
399 * The "info source" command now displays the producer string if it was
400 present in the debug info. This typically includes the compiler version
401 and may include things like its command line arguments.
403 * The "info dll", an alias of the "info sharedlibrary" command,
404 is now available on all platforms.
406 * Directory names supplied to the "set sysroot" commands may be
407 prefixed with "target:" to tell GDB to access shared libraries from
408 the target system, be it local or remote. This replaces the prefix
409 "remote:". The default sysroot has been changed from "" to
410 "target:". "remote:" is automatically converted to "target:" for
411 backward compatibility.
413 * The system root specified by "set sysroot" will be prepended to the
414 filename of the main executable (if reported to GDB as absolute by
415 the operating system) when starting processes remotely, and when
416 attaching to already-running local or remote processes.
418 * GDB now supports automatic location and retrieval of executable
419 files from remote targets. Remote debugging can now be initiated
420 using only a "target remote" or "target extended-remote" command
421 (no "set sysroot" or "file" commands are required). See "New remote
424 * The "dump" command now supports verilog hex format.
426 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
428 * On GNU/Linux, GDB and gdbserver are now able to access executable
429 and shared library files without a "set sysroot" command when
430 attaching to processes running in different mount namespaces from
431 the debugger. This makes it possible to attach to processes in
432 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
433 See "New remote packets" below.
435 * The "tui reg" command now provides completion for all of the
436 available register groups, including target specific groups.
438 * The HISTSIZE environment variable is no longer read when determining
439 the size of GDB's command history. GDB now instead reads the dedicated
440 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
441 disables truncation of command history. Non-numeric values of GDBHISTSIZE
446 ** Memory ports can now be unbuffered.
450 ** gdb.Objfile objects have a new attribute "username",
451 which is the name of the objfile as specified by the user,
452 without, for example, resolving symlinks.
453 ** You can now write frame unwinders in Python.
454 ** gdb.Type objects have a new method "optimized_out",
455 returning optimized out gdb.Value instance of this type.
456 ** gdb.Value objects have new methods "reference_value" and
457 "const_value" which return a reference to the value and a
458 "const" version of the value respectively.
462 maint print symbol-cache
463 Print the contents of the symbol cache.
465 maint print symbol-cache-statistics
466 Print statistics of symbol cache usage.
468 maint flush-symbol-cache
469 Flush the contents of the symbol cache.
473 Start branch trace recording using Branch Trace Store (BTS) format.
476 Evaluate expression by using the compiler and print result.
480 Explicit commands for enabling and disabling tui mode.
483 set mpx bound on i386 and amd64
484 Support for bound table investigation on Intel MPX enabled applications.
488 Start branch trace recording using Intel Processor Trace format.
491 Print information about branch tracing internals.
493 maint btrace packet-history
494 Print the raw branch tracing data.
496 maint btrace clear-packet-history
497 Discard the stored raw branch tracing data.
500 Discard all branch tracing data. It will be fetched and processed
501 anew by the next "record" command.
506 Renamed from "set debug dwarf2-die".
508 Renamed from "show debug dwarf2-die".
511 Renamed from "set debug dwarf2-read".
512 show debug dwarf-read
513 Renamed from "show debug dwarf2-read".
515 maint set dwarf always-disassemble
516 Renamed from "maint set dwarf2 always-disassemble".
517 maint show dwarf always-disassemble
518 Renamed from "maint show dwarf2 always-disassemble".
520 maint set dwarf max-cache-age
521 Renamed from "maint set dwarf2 max-cache-age".
522 maint show dwarf max-cache-age
523 Renamed from "maint show dwarf2 max-cache-age".
526 show debug dwarf-line
527 Control display of debugging info regarding DWARF line processing.
531 Set the maximum number of candidates to be considered during
532 completion. The default value is 200. This limit allows GDB
533 to avoid generating large completion lists, the computation of
534 which can cause the debugger to become temporarily unresponsive.
536 set history remove-duplicates
537 show history remove-duplicates
538 Control the removal of duplicate history entries.
540 maint set symbol-cache-size
541 maint show symbol-cache-size
542 Control the size of the symbol cache.
544 set|show record btrace bts buffer-size
545 Set and show the size of the ring buffer used for branch tracing in
547 The obtained size may differ from the requested size. Use "info
548 record" to see the obtained buffer size.
550 set debug linux-namespaces
551 show debug linux-namespaces
552 Control display of debugging info regarding Linux namespaces.
554 set|show record btrace pt buffer-size
555 Set and show the size of the ring buffer used for branch tracing in
556 Intel Processor Trace format.
557 The obtained size may differ from the requested size. Use "info
558 record" to see the obtained buffer size.
560 maint set|show btrace pt skip-pad
561 Set and show whether PAD packets are skipped when computing the
564 * The command 'thread apply all' can now support new option '-ascending'
565 to call its specified command for all threads in ascending order.
567 * Python/Guile scripting
569 ** GDB now supports auto-loading of Python/Guile scripts contained in the
570 special section named `.debug_gdb_scripts'.
574 qXfer:btrace-conf:read
575 Return the branch trace configuration for the current thread.
577 Qbtrace-conf:bts:size
578 Set the requested ring buffer size for branch tracing in BTS format.
581 Enable Intel Procesor Trace-based branch tracing for the current
582 process. The remote stub reports support for this packet to GDB's
586 Set the requested ring buffer size for branch tracing in Intel Processor
590 Indicates a memory breakpoint instruction was executed, irrespective
591 of whether it was GDB that planted the breakpoint or the breakpoint
592 is hardcoded in the program. This is required for correct non-stop
596 Indicates the target stopped for a hardware breakpoint. This is
597 required for correct non-stop mode operation.
600 Return information about files on the remote system.
603 Return the full absolute name of the file that was executed to
604 create a process running on the remote system.
607 Select the filesystem on which vFile: operations with filename
608 arguments will operate. This is required for GDB to be able to
609 access files on remote targets where the remote stub does not
610 share a common filesystem with the inferior(s).
613 Indicates that a fork system call was executed.
616 Indicates that a vfork system call was executed.
618 vforkdone stop reason
619 Indicates that a vfork child of the specified process has executed
620 an exec or exit, allowing the vfork parent to resume execution.
622 fork-events and vfork-events features in qSupported
623 The qSupported packet allows GDB to request support for fork and
624 vfork events using new 'gdbfeatures' fork-events and vfork-events,
625 and the qSupported response can contain the corresponding
626 'stubfeatures'. Set and show commands can be used to display
627 whether these features are enabled.
629 * Extended-remote fork events
631 ** GDB now has support for fork events on extended-remote Linux
632 targets. For targets with Linux kernels 2.5.60 and later, this
633 enables follow-fork-mode and detach-on-fork for both fork and
634 vfork, as well as fork and vfork catchpoints.
636 * The info record command now shows the recording format and the
637 branch tracing configuration for the current thread when using
638 the btrace record target.
639 For the BTS format, it shows the ring buffer size.
641 * GDB now has support for DTrace USDT (Userland Static Defined
642 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
644 * GDB now supports access to vector registers on S/390 GNU/Linux
647 * Removed command line options
649 -xdb HP-UX XDB compatibility mode.
651 * Removed targets and native configurations
653 HP/PA running HP-UX hppa*-*-hpux*
654 Itanium running HP-UX ia64-*-hpux*
656 * New configure options
659 This configure option allows the user to build GDB with support for
660 Intel Processor Trace (default: auto). This requires libipt.
662 --with-libipt-prefix=PATH
663 Specify the path to the version of libipt that GDB should use.
664 $PATH/include should contain the intel-pt.h header and
665 $PATH/lib should contain the libipt.so library.
667 *** Changes in GDB 7.9.1
671 ** Xmethods can now specify a result type.
673 *** Changes in GDB 7.9
675 * GDB now supports hardware watchpoints on x86 GNU Hurd.
679 ** You can now access frame registers from Python scripts.
680 ** New attribute 'producer' for gdb.Symtab objects.
681 ** gdb.Objfile objects have a new attribute "progspace",
682 which is the gdb.Progspace object of the containing program space.
683 ** gdb.Objfile objects have a new attribute "owner".
684 ** gdb.Objfile objects have a new attribute "build_id",
685 which is the build ID generated when the file was built.
686 ** gdb.Objfile objects have a new method "add_separate_debug_file".
687 ** A new event "gdb.clear_objfiles" has been added, triggered when
688 selecting a new file to debug.
689 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
690 ** New function gdb.lookup_objfile.
692 New events which are triggered when GDB modifies the state of the
695 ** gdb.events.inferior_call_pre: Function call is about to be made.
696 ** gdb.events.inferior_call_post: Function call has just been made.
697 ** gdb.events.memory_changed: A memory location has been altered.
698 ** gdb.events.register_changed: A register has been altered.
700 * New Python-based convenience functions:
702 ** $_caller_is(name [, number_of_frames])
703 ** $_caller_matches(regexp [, number_of_frames])
704 ** $_any_caller_is(name [, number_of_frames])
705 ** $_any_caller_matches(regexp [, number_of_frames])
707 * GDB now supports the compilation and injection of source code into
708 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
709 to compile the source code to object code, and if successful, inject
710 and execute that code within the current context of the inferior.
711 Currently the C language is supported. The commands used to
712 interface with this new feature are:
714 compile code [-raw|-r] [--] [source code]
715 compile file [-raw|-r] filename
719 demangle [-l language] [--] name
720 Demangle "name" in the specified language, or the current language
721 if elided. This command is renamed from the "maint demangle" command.
722 The latter is kept as a no-op to avoid "maint demangle" being interpreted
723 as "maint demangler-warning".
725 queue-signal signal-name-or-number
726 Queue a signal to be delivered to the thread when it is resumed.
728 add-auto-load-scripts-directory directory
729 Add entries to the list of directories from which to load auto-loaded
732 maint print user-registers
733 List all currently available "user" registers.
735 compile code [-r|-raw] [--] [source code]
736 Compile, inject, and execute in the inferior the executable object
737 code produced by compiling the provided source code.
739 compile file [-r|-raw] filename
740 Compile and inject into the inferior the executable object code
741 produced by compiling the source code stored in the filename
744 * On resume, GDB now always passes the signal the program had stopped
745 for to the thread the signal was sent to, even if the user changed
746 threads before resuming. Previously GDB would often (but not
747 always) deliver the signal to the thread that happens to be current
750 * Conversely, the "signal" command now consistently delivers the
751 requested signal to the current thread. GDB now asks for
752 confirmation if the program had stopped for a signal and the user
753 switched threads meanwhile.
755 * "breakpoint always-inserted" modes "off" and "auto" merged.
757 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
758 won't remove breakpoints from the target until all threads stop,
759 even in non-stop mode. The "auto" mode has been removed, and "off"
760 is now the default mode.
764 set debug symbol-lookup
765 show debug symbol-lookup
766 Control display of debugging info regarding symbol lookup.
770 ** The -list-thread-groups command outputs an exit-code field for
771 inferiors that have exited.
775 MIPS SDE mips*-sde*-elf*
779 Support for these obsolete configurations has been removed.
781 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
782 SGI Irix-5.x mips-*-irix5*
783 SGI Irix-6.x mips-*-irix6*
784 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
785 VAX running Ultrix vax-*-ultrix*
787 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
788 and "assf"), have been removed. Use the "sharedlibrary" command, or
789 its alias "share", instead.
791 *** Changes in GDB 7.8
793 * New command line options
796 This is an alias for the --data-directory option.
798 * GDB supports printing and modifying of variable length automatic arrays
799 as specified in ISO C99.
801 * The ARM simulator now supports instruction level tracing
802 with or without disassembly.
806 GDB now has support for scripting using Guile. Whether this is
807 available is determined at configure time.
808 Guile version 2.0 or greater is required.
809 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
811 * New commands (for set/show, see "New options" below)
815 Invoke CODE by passing it to the Guile interpreter.
819 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
821 info auto-load guile-scripts [regexp]
822 Print the list of automatically loaded Guile scripts.
824 * The source command is now capable of sourcing Guile scripts.
825 This feature is dependent on the debugger being built with Guile support.
829 set print symbol-loading (off|brief|full)
830 show print symbol-loading
831 Control whether to print informational messages when loading symbol
832 information for a file. The default is "full", but when debugging
833 programs with large numbers of shared libraries the amount of output
836 set guile print-stack (none|message|full)
837 show guile print-stack
838 Show a stack trace when an error is encountered in a Guile script.
840 set auto-load guile-scripts (on|off)
841 show auto-load guile-scripts
842 Control auto-loading of Guile script files.
844 maint ada set ignore-descriptive-types (on|off)
845 maint ada show ignore-descriptive-types
846 Control whether the debugger should ignore descriptive types in Ada
847 programs. The default is not to ignore the descriptive types. See
848 the user manual for more details on descriptive types and the intended
849 usage of this option.
851 set auto-connect-native-target
853 Control whether GDB is allowed to automatically connect to the
854 native target for the run, attach, etc. commands when not connected
855 to any target yet. See also "target native" below.
857 set record btrace replay-memory-access (read-only|read-write)
858 show record btrace replay-memory-access
859 Control what memory accesses are allowed during replay.
861 maint set target-async (on|off)
862 maint show target-async
863 This controls whether GDB targets operate in synchronous or
864 asynchronous mode. Normally the default is asynchronous, if it is
865 available; but this can be changed to more easily debug problems
866 occurring only in synchronous mode.
868 set mi-async (on|off)
870 Control whether MI asynchronous mode is preferred. This supersedes
871 "set target-async" of previous GDB versions.
873 * "set target-async" is deprecated as a CLI option and is now an alias
874 for "set mi-async" (only puts MI into async mode).
876 * Background execution commands (e.g., "c&", "s&", etc.) are now
877 possible ``out of the box'' if the target supports them. Previously
878 the user would need to explicitly enable the possibility with the
879 "set target-async on" command.
881 * New features in the GDB remote stub, GDBserver
883 ** New option --debug-format=option1[,option2,...] allows one to add
884 additional text to each output. At present only timestamps
885 are supported: --debug-format=timestamps.
886 Timestamps can also be turned on with the
887 "monitor set debug-format timestamps" command from GDB.
889 * The 'record instruction-history' command now starts counting instructions
890 at one. This also affects the instruction ranges reported by the
891 'record function-call-history' command when given the /i modifier.
893 * The command 'record function-call-history' supports a new modifier '/c' to
894 indent the function names based on their call stack depth.
895 The fields for the '/i' and '/l' modifier have been reordered.
896 The source line range is now prefixed with 'at'.
897 The instruction range is now prefixed with 'inst'.
898 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
899 "record instruction-history" and "list" commands.
901 * The ranges given as arguments to the 'record function-call-history' and
902 'record instruction-history' commands are now inclusive.
904 * The btrace record target now supports the 'record goto' command.
905 For locations inside the execution trace, the back trace is computed
906 based on the information stored in the execution trace.
908 * The btrace record target supports limited reverse execution and replay.
909 The target does not record data and therefore does not allow reading
912 * The "catch syscall" command now works on s390*-linux* targets.
914 * The "compare-sections" command is no longer specific to target
915 remote. It now works with all targets.
917 * All native targets are now consistently called "native".
918 Consequently, the "target child", "target GNU", "target djgpp",
919 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
920 commands have been replaced with "target native". The QNX/NTO port
921 leaves the "procfs" target in place and adds a "native" target for
922 consistency with other ports. The impact on users should be minimal
923 as these commands previously either throwed an error, or were
924 no-ops. The target's name is visible in the output of the following
925 commands: "help target", "info target", "info files", "maint print
928 * The "target native" command now connects to the native target. This
929 can be used to launch native programs even when "set
930 auto-connect-native-target" is set to off.
932 * GDB now supports access to Intel MPX registers on GNU/Linux.
934 * Support for Intel AVX-512 registers on GNU/Linux.
935 Support displaying and modifying Intel AVX-512 registers
936 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
940 qXfer:btrace:read's annex
941 The qXfer:btrace:read packet supports a new annex 'delta' to read
942 branch trace incrementally.
946 ** Valid Python operations on gdb.Value objects representing
947 structs/classes invoke the corresponding overloaded operators if
949 ** New `Xmethods' feature in the Python API. Xmethods are
950 additional methods or replacements for existing methods of a C++
951 class. This feature is useful for those cases where a method
952 defined in C++ source code could be inlined or optimized out by
953 the compiler, making it unavailable to GDB.
956 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
958 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
959 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
960 its alias "share", instead.
962 * The commands "set remotebaud" and "show remotebaud" are no longer
963 supported. Use "set serial baud" and "show serial baud" (respectively)
968 ** A new option "-gdb-set mi-async" replaces "-gdb-set
969 target-async". The latter is left as a deprecated alias of the
970 former for backward compatibility. If the target supports it,
971 CLI background execution commands are now always possible by
972 default, independently of whether the frontend stated a
973 preference for asynchronous execution with "-gdb-set mi-async".
974 Previously "-gdb-set target-async off" affected both MI execution
975 commands and CLI execution commands.
977 *** Changes in GDB 7.7
979 * Improved support for process record-replay and reverse debugging on
980 arm*-linux* targets. Support for thumb32 and syscall instruction
981 recording has been added.
983 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
985 * GDB now supports Fission DWP file format version 2.
986 http://gcc.gnu.org/wiki/DebugFission
988 * New convenience function "$_isvoid", to check whether an expression
989 is void. A void expression is an expression where the type of the
990 result is "void". For example, some convenience variables may be
991 "void" when evaluated (e.g., "$_exitcode" before the execution of
992 the program being debugged; or an undefined convenience variable).
993 Another example, when calling a function whose return type is
996 * The "maintenance print objfiles" command now takes an optional regexp.
998 * The "catch syscall" command now works on arm*-linux* targets.
1000 * GDB now consistently shows "<not saved>" when printing values of
1001 registers the debug info indicates have not been saved in the frame
1002 and there's nowhere to retrieve them from
1003 (callee-saved/call-clobbered registers):
1008 (gdb) info registers rax
1011 Before, the former would print "<optimized out>", and the latter
1012 "*value not available*".
1014 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1019 ** Frame filters and frame decorators have been added.
1020 ** Temporary breakpoints are now supported.
1021 ** Line tables representation has been added.
1022 ** New attribute 'parent_type' for gdb.Field objects.
1023 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1024 ** New attribute 'name' for gdb.Type objects.
1028 Nios II ELF nios2*-*-elf
1029 Nios II GNU/Linux nios2*-*-linux
1030 Texas Instruments MSP430 msp430*-*-elf
1032 * Removed native configurations
1034 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1035 been removed. ELF variants of these configurations are kept supported.
1037 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1038 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1039 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1040 i[34567]86-*-openbsd3.[0-3]
1041 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1042 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1043 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1047 Like "catch throw", but catches a re-thrown exception.
1048 maint check-psymtabs
1049 Renamed from old "maint check-symtabs".
1051 Perform consistency checks on symtabs.
1052 maint expand-symtabs
1053 Expand symtabs matching an optional regexp.
1056 Display the details of GDB configure-time options.
1058 maint set|show per-command
1059 maint set|show per-command space
1060 maint set|show per-command time
1061 maint set|show per-command symtab
1062 Enable display of per-command gdb resource usage.
1064 remove-symbol-file FILENAME
1065 remove-symbol-file -a ADDRESS
1066 Remove a symbol file added via add-symbol-file. The file to remove
1067 can be identified by its filename or by an address that lies within
1068 the boundaries of this symbol file in memory.
1071 info exceptions REGEXP
1072 Display the list of Ada exceptions defined in the program being
1073 debugged. If provided, only the exceptions whose names match REGEXP
1078 set debug symfile off|on
1080 Control display of debugging info regarding reading symbol files and
1081 symbol tables within those files
1083 set print raw frame-arguments
1084 show print raw frame-arguments
1085 Set/show whether to print frame arguments in raw mode,
1086 disregarding any defined pretty-printers.
1088 set remote trace-status-packet
1089 show remote trace-status-packet
1090 Set/show the use of remote protocol qTStatus packet.
1094 Control display of debugging messages related to Nios II targets.
1098 Control whether target-assisted range stepping is enabled.
1100 set startup-with-shell
1101 show startup-with-shell
1102 Specifies whether Unix child processes are started via a shell or
1107 Use the target memory cache for accesses to the code segment. This
1108 improves performance of remote debugging (particularly disassembly).
1110 * You can now use a literal value 'unlimited' for options that
1111 interpret 0 or -1 as meaning "unlimited". E.g., "set
1112 trace-buffer-size unlimited" is now an alias for "set
1113 trace-buffer-size -1" and "set height unlimited" is now an alias for
1116 * The "set debug symtab-create" debugging option of GDB has been changed to
1117 accept a verbosity level. 0 means "off", 1 provides basic debugging
1118 output, and values of 2 or greater provides more verbose output.
1120 * New command-line options
1122 Display the details of GDB configure-time options.
1124 * The command 'tsave' can now support new option '-ctf' to save trace
1125 buffer in Common Trace Format.
1127 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1130 * GDB now implements the the C++ 'typeid' operator.
1132 * The new convenience variable $_exception holds the exception being
1133 thrown or caught at an exception-related catchpoint.
1135 * The exception-related catchpoints, like "catch throw", now accept a
1136 regular expression which can be used to filter exceptions by type.
1138 * The new convenience variable $_exitsignal is automatically set to
1139 the terminating signal number when the program being debugged dies
1140 due to an uncaught signal.
1144 ** All MI commands now accept an optional "--language" option.
1145 Support for this feature can be verified by using the "-list-features"
1146 command, which should contain "language-option".
1148 ** The new command -info-gdb-mi-command allows the user to determine
1149 whether a GDB/MI command is supported or not.
1151 ** The "^error" result record returned when trying to execute an undefined
1152 GDB/MI command now provides a variable named "code" whose content is the
1153 "undefined-command" error code. Support for this feature can be verified
1154 by using the "-list-features" command, which should contain
1155 "undefined-command-error-code".
1157 ** The -trace-save MI command can optionally save trace buffer in Common
1160 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1162 ** The command -data-list-register-values now accepts an optional
1163 "--skip-unavailable" option. When used, only the available registers
1166 ** The new command -trace-frame-collected dumps collected variables,
1167 computed expressions, tvars, memory and registers in a traceframe.
1169 ** The commands -stack-list-locals, -stack-list-arguments and
1170 -stack-list-variables now accept an option "--skip-unavailable".
1171 When used, only the available locals or arguments are displayed.
1173 ** The -exec-run command now accepts an optional "--start" option.
1174 When used, the command follows the same semantics as the "start"
1175 command, stopping the program's execution at the start of its
1176 main subprogram. Support for this feature can be verified using
1177 the "-list-features" command, which should contain
1178 "exec-run-start-option".
1180 ** The new commands -catch-assert and -catch-exceptions insert
1181 catchpoints stopping the program when Ada exceptions are raised.
1183 ** The new command -info-ada-exceptions provides the equivalent of
1184 the new "info exceptions" command.
1186 * New system-wide configuration scripts
1187 A GDB installation now provides scripts suitable for use as system-wide
1188 configuration scripts for the following systems:
1192 * GDB now supports target-assigned range stepping with remote targets.
1193 This improves the performance of stepping source lines by reducing
1194 the number of control packets from/to GDB. See "New remote packets"
1197 * GDB now understands the element 'tvar' in the XML traceframe info.
1198 It has the id of the collected trace state variables.
1200 * On S/390 targets that provide the transactional-execution feature,
1201 the program interruption transaction diagnostic block (TDB) is now
1202 represented as a number of additional "registers" in GDB.
1204 * New remote packets
1208 The vCont packet supports a new 'r' action, that tells the remote
1209 stub to step through an address range itself, without GDB
1210 involvemement at each single-step.
1212 qXfer:libraries-svr4:read's annex
1213 The previously unused annex of the qXfer:libraries-svr4:read packet
1214 is now used to support passing an argument list. The remote stub
1215 reports support for this argument list to GDB's qSupported query.
1216 The defined arguments are "start" and "prev", used to reduce work
1217 necessary for library list updating, resulting in significant
1220 * New features in the GDB remote stub, GDBserver
1222 ** GDBserver now supports target-assisted range stepping. Currently
1223 enabled on x86/x86_64 GNU/Linux targets.
1225 ** GDBserver now adds element 'tvar' in the XML in the reply to
1226 'qXfer:traceframe-info:read'. It has the id of the collected
1227 trace state variables.
1229 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1232 * New 'z' formatter for printing and examining memory, this displays the
1233 value as hexadecimal zero padded on the left to the size of the type.
1235 * GDB can now use Windows x64 unwinding data.
1237 * The "set remotebaud" command has been replaced by "set serial baud".
1238 Similarly, "show remotebaud" has been replaced by "show serial baud".
1239 The "set remotebaud" and "show remotebaud" commands are still available
1240 to provide backward compatibility with older versions of GDB.
1242 *** Changes in GDB 7.6
1244 * Target record has been renamed to record-full.
1245 Record/replay is now enabled with the "record full" command.
1246 This also affects settings that are associated with full record/replay
1247 that have been moved from "set/show record" to "set/show record full":
1249 set|show record full insn-number-max
1250 set|show record full stop-at-limit
1251 set|show record full memory-query
1253 * A new record target "record-btrace" has been added. The new target
1254 uses hardware support to record the control-flow of a process. It
1255 does not support replaying the execution, but it implements the
1256 below new commands for investigating the recorded execution log.
1257 This new recording method can be enabled using:
1261 The "record-btrace" target is only available on Intel Atom processors
1262 and requires a Linux kernel 2.6.32 or later.
1264 * Two new commands have been added for record/replay to give information
1265 about the recorded execution without having to replay the execution.
1266 The commands are only supported by "record btrace".
1268 record instruction-history prints the execution history at
1269 instruction granularity
1271 record function-call-history prints the execution history at
1272 function granularity
1274 * New native configurations
1276 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1277 FreeBSD/powerpc powerpc*-*-freebsd
1278 x86_64/Cygwin x86_64-*-cygwin*
1279 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1283 ARM AArch64 aarch64*-*-elf
1284 ARM AArch64 GNU/Linux aarch64*-*-linux
1285 Lynx 178 PowerPC powerpc-*-lynx*178
1286 x86_64/Cygwin x86_64-*-cygwin*
1287 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1289 * If the configured location of system.gdbinit file (as given by the
1290 --with-system-gdbinit option at configure time) is in the
1291 data-directory (as specified by --with-gdb-datadir at configure
1292 time) or in one of its subdirectories, then GDB will look for the
1293 system-wide init file in the directory specified by the
1294 --data-directory command-line option.
1296 * New command line options:
1298 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1299 other initialization files, unlike -nx which disables all of them.
1301 * Removed command line options
1303 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1306 * The 'ptype' and 'whatis' commands now accept an argument to control
1309 * 'info proc' now works on some core files.
1313 ** Vectors can be created with gdb.Type.vector.
1315 ** Python's atexit.register now works in GDB.
1317 ** Types can be pretty-printed via a Python API.
1319 ** Python 3 is now supported (in addition to Python 2.4 or later)
1321 ** New class gdb.Architecture exposes GDB's internal representation
1322 of architecture in the Python API.
1324 ** New method Frame.architecture returns the gdb.Architecture object
1325 corresponding to the frame's architecture.
1327 * New Python-based convenience functions:
1329 ** $_memeq(buf1, buf2, length)
1330 ** $_streq(str1, str2)
1332 ** $_regex(str, regex)
1334 * The 'cd' command now defaults to using '~' (the home directory) if not
1337 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1338 default for GCC since November 2000.
1340 * The command 'forward-search' can now be abbreviated as 'fo'.
1342 * The command 'info tracepoints' can now display 'installed on target'
1343 or 'not installed on target' for each non-pending location of tracepoint.
1345 * New configure options
1347 --enable-libmcheck/--disable-libmcheck
1348 By default, development versions are built with -lmcheck on hosts
1349 that support it, in order to help track memory corruption issues.
1350 Release versions, on the other hand, are built without -lmcheck
1351 by default. The --enable-libmcheck/--disable-libmcheck configure
1352 options allow the user to override that default.
1353 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1354 This configure option allows the user to build GDB with
1355 libbabeltrace using which GDB can read Common Trace Format data.
1357 * New commands (for set/show, see "New options" below)
1360 Catch signals. This is similar to "handle", but allows commands and
1361 conditions to be attached.
1364 List the BFDs known to GDB.
1366 python-interactive [command]
1368 Start a Python interactive prompt, or evaluate the optional command
1369 and print the result of expressions.
1372 "py" is a new alias for "python".
1374 enable type-printer [name]...
1375 disable type-printer [name]...
1376 Enable or disable type printers.
1380 ** For the Renesas Super-H architecture, the "regs" command has been removed
1381 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1386 set print type methods (on|off)
1387 show print type methods
1388 Control whether method declarations are displayed by "ptype".
1389 The default is to show them.
1391 set print type typedefs (on|off)
1392 show print type typedefs
1393 Control whether typedef definitions are displayed by "ptype".
1394 The default is to show them.
1396 set filename-display basename|relative|absolute
1397 show filename-display
1398 Control the way in which filenames is displayed.
1399 The default is "relative", which preserves previous behavior.
1401 set trace-buffer-size
1402 show trace-buffer-size
1403 Request target to change the size of trace buffer.
1405 set remote trace-buffer-size-packet auto|on|off
1406 show remote trace-buffer-size-packet
1407 Control the use of the remote protocol `QTBuffer:size' packet.
1411 Control display of debugging messages related to ARM AArch64.
1414 set debug coff-pe-read
1415 show debug coff-pe-read
1416 Control display of debugging messages related to reading of COFF/PE
1421 Control display of debugging messages related to Mach-O symbols
1424 set debug notification
1425 show debug notification
1426 Control display of debugging info for async remote notification.
1430 ** Command parameter changes are now notified using new async record
1431 "=cmd-param-changed".
1432 ** Trace frame changes caused by command "tfind" are now notified using
1433 new async record "=traceframe-changed".
1434 ** The creation, deletion and modification of trace state variables
1435 are now notified using new async records "=tsv-created",
1436 "=tsv-deleted" and "=tsv-modified".
1437 ** The start and stop of process record are now notified using new
1438 async record "=record-started" and "=record-stopped".
1439 ** Memory changes are now notified using new async record
1441 ** The data-disassemble command response will include a "fullname" field
1442 containing the absolute file name when source has been requested.
1443 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1444 command, to allow pattern filling of memory areas.
1445 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1446 library load/unload events.
1447 ** The response to breakpoint commands and breakpoint async records
1448 includes an "installed" field containing a boolean state about each
1449 non-pending tracepoint location is whether installed on target or not.
1450 ** Output of the "-trace-status" command includes a "trace-file" field
1451 containing the name of the trace file being examined. This field is
1452 optional, and only present when examining a trace file.
1453 ** The "fullname" field is now always present along with the "file" field,
1454 even if the file cannot be found by GDB.
1456 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1457 You must have the LZMA library available when configuring GDB for this
1458 feature to be enabled. For more information, see:
1459 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1461 * New remote packets
1464 Set the size of trace buffer. The remote stub reports support for this
1465 packet to gdb's qSupported query.
1468 Enable Branch Trace Store (BTS)-based branch tracing for the current
1469 thread. The remote stub reports support for this packet to gdb's
1473 Disable branch tracing for the current thread. The remote stub reports
1474 support for this packet to gdb's qSupported query.
1477 Read the traced branches for the current thread. The remote stub
1478 reports support for this packet to gdb's qSupported query.
1480 *** Changes in GDB 7.5
1482 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1483 for more x32 ABI info.
1485 * GDB now supports access to MIPS DSP registers on Linux targets.
1487 * GDB now supports debugging microMIPS binaries.
1489 * The "info os" command on GNU/Linux can now display information on
1490 several new classes of objects managed by the operating system:
1491 "info os procgroups" lists process groups
1492 "info os files" lists file descriptors
1493 "info os sockets" lists internet-domain sockets
1494 "info os shm" lists shared-memory regions
1495 "info os semaphores" lists semaphores
1496 "info os msg" lists message queues
1497 "info os modules" lists loaded kernel modules
1499 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1500 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1501 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1502 options and inspect the probe arguments using the new $_probe_arg family
1503 of convenience variables. You can obtain more information about SystemTap
1504 in <http://sourceware.org/systemtap/>.
1506 * GDB now supports reversible debugging on ARM, it allows you to
1507 debug basic ARM and THUMB instructions, and provides
1508 record/replay support.
1510 * The option "symbol-reloading" has been deleted as it is no longer used.
1514 ** GDB commands implemented in Python can now be put in command class
1517 ** The "maint set python print-stack on|off" is now deleted.
1519 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1520 apply "flag enum"-style pretty-printing to any enum.
1522 ** gdb.lookup_symbol can now work when there is no current frame.
1524 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1525 the source at which the symbol was defined.
1527 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1528 method 'value'. The former indicates whether the symbol needs a
1529 frame in order to compute its value, and the latter computes the
1532 ** A new method 'referenced_value' on gdb.Value objects which can
1533 dereference pointer as well as C++ reference values.
1535 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1536 which return the global and static blocks (as gdb.Block objects),
1537 of the underlying symbol table, respectively.
1539 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1540 object associated with a PC value.
1542 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1543 of the address range occupied by code for the current source line.
1545 * Go language support.
1546 GDB now supports debugging programs written in the Go programming
1549 * GDBserver now supports stdio connections.
1550 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1552 * The binary "gdbtui" can no longer be built or installed.
1553 Use "gdb -tui" instead.
1555 * GDB will now print "flag" enums specially. A flag enum is one where
1556 all the enumerator values have no bits in common when pairwise
1557 "and"ed. When printing a value whose type is a flag enum, GDB will
1558 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1559 (gdb) print (enum E) 3
1562 * The filename part of a linespec will now match trailing components
1563 of a source file name. For example, "break gcc/expr.c:1000" will
1564 now set a breakpoint in build/gcc/expr.c, but not
1565 build/libcpp/expr.c.
1567 * The "info proc" and "generate-core-file" commands will now also
1568 work on remote targets connected to GDBserver on Linux.
1570 * The command "info catch" has been removed. It has been disabled
1571 since December 2007.
1573 * The "catch exception" and "catch assert" commands now accept
1574 a condition at the end of the command, much like the "break"
1575 command does. For instance:
1577 (gdb) catch exception Constraint_Error if Barrier = True
1579 Previously, it was possible to add a condition to such catchpoints,
1580 but it had to be done as a second step, after the catchpoint had been
1581 created, using the "condition" command.
1583 * The "info static-tracepoint-marker" command will now also work on
1584 native Linux targets with in-process agent.
1586 * GDB can now set breakpoints on inlined functions.
1588 * The .gdb_index section has been updated to include symbols for
1589 inlined functions. GDB will ignore older .gdb_index sections by
1590 default, which could cause symbol files to be loaded more slowly
1591 until their .gdb_index sections can be recreated. The new command
1592 "set use-deprecated-index-sections on" will cause GDB to use any older
1593 .gdb_index sections it finds. This will restore performance, but the
1594 ability to set breakpoints on inlined functions will be lost in symbol
1595 files with older .gdb_index sections.
1597 The .gdb_index section has also been updated to record more information
1598 about each symbol. This speeds up the "info variables", "info functions"
1599 and "info types" commands when used with programs having the .gdb_index
1600 section, as well as speeding up debugging with shared libraries using
1601 the .gdb_index section.
1603 * Ada support for GDB/MI Variable Objects has been added.
1605 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1610 ** New command -info-os is the MI equivalent of "info os".
1612 ** Output logs ("set logging" and related) now include MI output.
1616 ** "set use-deprecated-index-sections on|off"
1617 "show use-deprecated-index-sections on|off"
1618 Controls the use of deprecated .gdb_index sections.
1620 ** "catch load" and "catch unload" can be used to stop when a shared
1621 library is loaded or unloaded, respectively.
1623 ** "enable count" can be used to auto-disable a breakpoint after
1626 ** "info vtbl" can be used to show the virtual method tables for
1627 C++ and Java objects.
1629 ** "explore" and its sub commands "explore value" and "explore type"
1630 can be used to recursively explore values and types of
1631 expressions. These commands are available only if GDB is
1632 configured with '--with-python'.
1634 ** "info auto-load" shows status of all kinds of auto-loaded files,
1635 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1636 sequences of commands files, "info auto-load python-scripts"
1637 shows status of auto-loading Python script files,
1638 "info auto-load local-gdbinit" shows status of loading init file
1639 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1640 status of inferior specific thread debugging shared library loading.
1642 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1643 and "show auto-load-scripts" commands have been deprecated, use their
1644 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1645 and "show auto-load python-scripts" counterparts instead.
1647 ** "dprintf location,format,args..." creates a dynamic printf, which
1648 is basically a breakpoint that does a printf and immediately
1649 resumes your program's execution, so it is like a printf that you
1650 can insert dynamically at runtime instead of at compiletime.
1652 ** "set print symbol"
1654 Controls whether GDB attempts to display the symbol, if any,
1655 corresponding to addresses it prints. This defaults to "on", but
1656 you can set it to "off" to restore GDB's previous behavior.
1658 * Deprecated commands
1660 ** For the Renesas Super-H architecture, the "regs" command has been
1661 deprecated, and "info all-registers" should be used instead.
1665 Renesas RL78 rl78-*-elf
1666 HP OpenVMS ia64 ia64-hp-openvms*
1668 * GDBserver supports evaluation of breakpoint conditions. When
1669 support is advertised by GDBserver, GDB may be told to send the
1670 breakpoint conditions in bytecode form to GDBserver. GDBserver
1671 will only report the breakpoint trigger to GDB when its condition
1676 set mips compression
1677 show mips compression
1678 Select the compressed ISA encoding used in functions that have no symbol
1679 information available. The encoding can be set to either of:
1682 and is updated automatically from ELF file flags if available.
1684 set breakpoint condition-evaluation
1685 show breakpoint condition-evaluation
1686 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1687 GDBserver ("target"). Default option "auto" chooses the most efficient
1689 This option can improve debugger efficiency depending on the speed of the
1693 Disable auto-loading globally.
1696 Show auto-loading setting of all kinds of auto-loaded files.
1698 set auto-load gdb-scripts on|off
1699 show auto-load gdb-scripts
1700 Control auto-loading of GDB canned sequences of commands files.
1702 set auto-load python-scripts on|off
1703 show auto-load python-scripts
1704 Control auto-loading of Python script files.
1706 set auto-load local-gdbinit on|off
1707 show auto-load local-gdbinit
1708 Control loading of init file (.gdbinit) from current directory.
1710 set auto-load libthread-db on|off
1711 show auto-load libthread-db
1712 Control auto-loading of inferior specific thread debugging shared library.
1714 set auto-load scripts-directory <dir1>[:<dir2>...]
1715 show auto-load scripts-directory
1716 Set a list of directories from which to load auto-loaded scripts.
1717 Automatically loaded Python scripts and GDB scripts are located in one
1718 of the directories listed by this option.
1719 The delimiter (':' above) may differ according to the host platform.
1721 set auto-load safe-path <dir1>[:<dir2>...]
1722 show auto-load safe-path
1723 Set a list of directories from which it is safe to auto-load files.
1724 The delimiter (':' above) may differ according to the host platform.
1726 set debug auto-load on|off
1727 show debug auto-load
1728 Control display of debugging info for auto-loading the files above.
1730 set dprintf-style gdb|call|agent
1732 Control the way in which a dynamic printf is performed; "gdb"
1733 requests a GDB printf command, while "call" causes dprintf to call a
1734 function in the inferior. "agent" requests that the target agent
1735 (such as GDBserver) do the printing.
1737 set dprintf-function <expr>
1738 show dprintf-function
1739 set dprintf-channel <expr>
1740 show dprintf-channel
1741 Set the function and optional first argument to the call when using
1742 the "call" style of dynamic printf.
1744 set disconnected-dprintf on|off
1745 show disconnected-dprintf
1746 Control whether agent-style dynamic printfs continue to be in effect
1747 after GDB disconnects.
1749 * New configure options
1751 --with-auto-load-dir
1752 Configure default value for the 'set auto-load scripts-directory'
1753 setting above. It defaults to '$debugdir:$datadir/auto-load',
1754 $debugdir representing global debugging info directories (available
1755 via 'show debug-file-directory') and $datadir representing GDB's data
1756 directory (available via 'show data-directory').
1758 --with-auto-load-safe-path
1759 Configure default value for the 'set auto-load safe-path' setting
1760 above. It defaults to the --with-auto-load-dir setting.
1762 --without-auto-load-safe-path
1763 Set 'set auto-load safe-path' to '/', effectively disabling this
1766 * New remote packets
1768 z0/z1 conditional breakpoints extension
1770 The z0/z1 breakpoint insertion packets have been extended to carry
1771 a list of conditional expressions over to the remote stub depending on the
1772 condition evaluation mode. The use of this extension can be controlled
1773 via the "set remote conditional-breakpoints-packet" command.
1777 Specify the signals which the remote stub may pass to the debugged
1778 program without GDB involvement.
1780 * New command line options
1782 --init-command=FILE, -ix Like --command, -x but execute it
1783 before loading inferior.
1784 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1785 execute it before loading inferior.
1787 *** Changes in GDB 7.4
1789 * GDB now handles ambiguous linespecs more consistently; the existing
1790 FILE:LINE support has been expanded to other types of linespecs. A
1791 breakpoint will now be set on all matching locations in all
1792 inferiors, and locations will be added or removed according to
1795 * GDB now allows you to skip uninteresting functions and files when
1796 stepping with the "skip function" and "skip file" commands.
1798 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1799 and "show remote hardware-watchpoint-length-limit". These allows to
1800 set or show the maximum length limit (in bytes) of a remote
1801 target hardware watchpoint.
1803 This allows e.g. to use "unlimited" hardware watchpoints with the
1804 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1805 watchpoints are slower than real hardware watchpoints but are
1806 significantly faster than gdb software watchpoints.
1810 ** The register_pretty_printer function in module gdb.printing now takes
1811 an optional `replace' argument. If True, the new printer replaces any
1814 ** The "maint set python print-stack on|off" command has been
1815 deprecated and will be deleted in GDB 7.5.
1816 A new command: "set python print-stack none|full|message" has
1817 replaced it. Additionally, the default for "print-stack" is
1818 now "message", which just prints the error message without
1821 ** A prompt substitution hook (prompt_hook) is now available to the
1824 ** A new Python module, gdb.prompt has been added to the GDB Python
1825 modules library. This module provides functionality for
1826 escape sequences in prompts (used by set/show
1827 extended-prompt). These escape sequences are replaced by their
1828 corresponding value.
1830 ** Python commands and convenience-functions located in
1831 'data-directory'/python/gdb/command and
1832 'data-directory'/python/gdb/function are now automatically loaded
1835 ** Blocks now provide four new attributes. global_block and
1836 static_block will return the global and static blocks
1837 respectively. is_static and is_global are boolean attributes
1838 that indicate if the block is one of those two types.
1840 ** Symbols now provide the "type" attribute, the type of the symbol.
1842 ** The "gdb.breakpoint" function has been deprecated in favor of
1845 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1846 of a function. This class is based on the "finish" command
1847 available in the CLI.
1849 ** Type objects for struct and union types now allow access to
1850 the fields using standard Python dictionary (mapping) methods.
1851 For example, "some_type['myfield']" now works, as does
1852 "some_type.items()".
1854 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1857 ** A new function, "deep_items" has been added to the gdb.types
1858 module in the GDB Python modules library. This function returns
1859 an iterator over the fields of a struct or union type. Unlike
1860 the standard Python "iteritems" method, it will recursively traverse
1861 any anonymous fields.
1865 ** "*stopped" events can report several new "reason"s, such as
1868 ** Breakpoint changes are now notified using new async records, like
1869 "=breakpoint-modified".
1871 ** New command -ada-task-info.
1873 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1874 $sdir specifies the default system locations of shared libraries.
1875 $pdir specifies the directory where the libpthread used by the application
1878 GDB no longer looks in $sdir and $pdir after it has searched the directories
1879 mentioned in libthread-db-search-path. If you want to search those
1880 directories, they must be specified in libthread-db-search-path.
1881 The default value of libthread-db-search-path on GNU/Linux and Solaris
1882 systems is now "$sdir:$pdir".
1884 $pdir is not supported by gdbserver, it is currently ignored.
1885 $sdir is supported by gdbserver.
1887 * New configure option --with-iconv-bin.
1888 When using the internationalization support like the one in the GNU C
1889 library, GDB will invoke the "iconv" program to get a list of supported
1890 character sets. If this program lives in a non-standard location, one can
1891 use this option to specify where to find it.
1893 * When natively debugging programs on PowerPC BookE processors running
1894 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1895 watchpoints, which specify a mask in addition to an address to watch.
1896 The mask specifies that some bits of an address (the bits which are
1897 reset in the mask) should be ignored when matching the address accessed
1898 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1899 section in the user manual for more details.
1901 * The new option --once causes GDBserver to stop listening for connections once
1902 the first connection is made. The listening port used by GDBserver will
1903 become available after that.
1905 * New commands "info macros" and "alias" have been added.
1907 * New function parameters suffix @entry specifies value of function parameter
1908 at the time the function got called. Entry values are available only since
1914 "!" is now an alias of the "shell" command.
1915 Note that no space is needed between "!" and SHELL COMMAND.
1919 watch EXPRESSION mask MASK_VALUE
1920 The watch command now supports the mask argument which allows creation
1921 of masked watchpoints, if the current architecture supports this feature.
1923 info auto-load-scripts [REGEXP]
1924 This command was formerly named "maintenance print section-scripts".
1925 It is now generally useful and is no longer a maintenance-only command.
1927 info macro [-all] [--] MACRO
1928 The info macro command has new options `-all' and `--'. The first for
1929 printing all definitions of a macro. The second for explicitly specifying
1930 the end of arguments and the beginning of the macro name in case the macro
1931 name starts with a hyphen.
1933 collect[/s] EXPRESSIONS
1934 The tracepoint collect command now takes an optional modifier "/s"
1935 that directs it to dereference pointer-to-character types and
1936 collect the bytes of memory up to a zero byte. The behavior is
1937 similar to what you see when you use the regular print command on a
1938 string. An optional integer following the "/s" sets a bound on the
1939 number of bytes that will be collected.
1942 The trace start command now interprets any supplied arguments as a
1943 note to be recorded with the trace run, with an effect similar to
1944 setting the variable trace-notes.
1947 The trace stop command now interprets any arguments as a note to be
1948 mentioned along with the tstatus report that the trace was stopped
1949 with a command. The effect is similar to setting the variable
1952 * Tracepoints can now be enabled and disabled at any time after a trace
1953 experiment has been started using the standard "enable" and "disable"
1954 commands. It is now possible to start a trace experiment with no enabled
1955 tracepoints; GDB will display a warning, but will allow the experiment to
1956 begin, assuming that tracepoints will be enabled as needed while the trace
1959 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1960 locations with 4-byte instructions, when they were previously
1961 limited to locations with instructions of 5 bytes or longer.
1965 set debug dwarf2-read
1966 show debug dwarf2-read
1967 Turns on or off display of debugging messages related to reading
1968 DWARF debug info. The default is off.
1970 set debug symtab-create
1971 show debug symtab-create
1972 Turns on or off display of debugging messages related to symbol table
1973 creation. The default is off.
1976 show extended-prompt
1977 Set the GDB prompt, and allow escape sequences to be inserted to
1978 display miscellaneous information (see 'help set extended-prompt'
1979 for the list of sequences). This prompt (and any information
1980 accessed through the escape sequences) is updated every time the
1981 prompt is displayed.
1983 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1984 show print entry-values
1985 Set printing of frame argument values at function entry. In some cases
1986 GDB can determine the value of function argument which was passed by the
1987 function caller, even if the value was modified inside the called function.
1989 set debug entry-values
1990 show debug entry-values
1991 Control display of debugging info for determining frame argument values at
1992 function entry and virtual tail call frames.
1994 set basenames-may-differ
1995 show basenames-may-differ
1996 Set whether a source file may have multiple base names.
1997 (A "base name" is the name of a file with the directory part removed.
1998 Example: The base name of "/home/user/hello.c" is "hello.c".)
1999 If set, GDB will canonicalize file names (e.g., expand symlinks)
2000 before comparing them. Canonicalization is an expensive operation,
2001 but it allows the same file be known by more than one base name.
2002 If not set (the default), all source files are assumed to have just
2003 one base name, and gdb will do file name comparisons more efficiently.
2009 Set a user name and notes for the current and any future trace runs.
2010 This is useful for long-running and/or disconnected traces, to
2011 inform others (or yourself) as to who is running the trace, supply
2012 contact information, or otherwise explain what is going on.
2014 set trace-stop-notes
2015 show trace-stop-notes
2016 Set a note attached to the trace run, that is displayed when the
2017 trace has been stopped by a tstop command. This is useful for
2018 instance as an explanation, if you are stopping a trace run that was
2019 started by someone else.
2021 * New remote packets
2025 Dynamically enable a tracepoint in a started trace experiment.
2029 Dynamically disable a tracepoint in a started trace experiment.
2033 Set the user and notes of the trace run.
2037 Query the current status of a tracepoint.
2041 Query the minimum length of instruction at which a fast tracepoint may
2044 * Dcache size (number of lines) and line-size are now runtime-configurable
2045 via "set dcache line" and "set dcache line-size" commands.
2049 Texas Instruments TMS320C6x tic6x-*-*
2053 Renesas RL78 rl78-*-elf
2055 *** Changes in GDB 7.3.1
2057 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2059 *** Changes in GDB 7.3
2061 * GDB has a new command: "thread find [REGEXP]".
2062 It finds the thread id whose name, target id, or thread extra info
2063 matches the given regular expression.
2065 * The "catch syscall" command now works on mips*-linux* targets.
2067 * The -data-disassemble MI command now supports modes 2 and 3 for
2068 dumping the instruction opcodes.
2070 * New command line options
2072 -data-directory DIR Specify DIR as the "data-directory".
2073 This is mostly for testing purposes.
2075 * The "maint set python auto-load on|off" command has been renamed to
2076 "set auto-load-scripts on|off".
2078 * GDB has a new command: "set directories".
2079 It is like the "dir" command except that it replaces the
2080 source path list instead of augmenting it.
2082 * GDB now understands thread names.
2084 On GNU/Linux, "info threads" will display the thread name as set by
2085 prctl or pthread_setname_np.
2087 There is also a new command, "thread name", which can be used to
2088 assign a name internally for GDB to display.
2091 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2092 has been integrated into GDB.
2096 ** The function gdb.Write now accepts an optional keyword 'stream'.
2097 This keyword, when provided, will direct the output to either
2098 stdout, stderr, or GDB's logging output.
2100 ** Parameters can now be be sub-classed in Python, and in particular
2101 you may implement the get_set_doc and get_show_doc functions.
2102 This improves how Parameter set/show documentation is processed
2103 and allows for more dynamic content.
2105 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2106 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2107 have an is_valid method.
2109 ** Breakpoints can now be sub-classed in Python, and in particular
2110 you may implement a 'stop' function that is executed each time
2111 the inferior reaches that breakpoint.
2113 ** New function gdb.lookup_global_symbol looks up a global symbol.
2115 ** GDB values in Python are now callable if the value represents a
2116 function. For example, if 'some_value' represents a function that
2117 takes two integer parameters and returns a value, you can call
2118 that function like so:
2120 result = some_value (10,20)
2122 ** Module gdb.types has been added.
2123 It contains a collection of utilities for working with gdb.Types objects:
2124 get_basic_type, has_field, make_enum_dict.
2126 ** Module gdb.printing has been added.
2127 It contains utilities for writing and registering pretty-printers.
2128 New classes: PrettyPrinter, SubPrettyPrinter,
2129 RegexpCollectionPrettyPrinter.
2130 New function: register_pretty_printer.
2132 ** New commands "info pretty-printers", "enable pretty-printer" and
2133 "disable pretty-printer" have been added.
2135 ** gdb.parameter("directories") is now available.
2137 ** New function gdb.newest_frame returns the newest frame in the
2140 ** The gdb.InferiorThread class has a new "name" attribute. This
2141 holds the thread's name.
2143 ** Python Support for Inferior events.
2144 Python scripts can add observers to be notified of events
2145 occurring in the process being debugged.
2146 The following events are currently supported:
2147 - gdb.events.cont Continue event.
2148 - gdb.events.exited Inferior exited event.
2149 - gdb.events.stop Signal received, and Breakpoint hit events.
2153 ** GDB now puts template parameters in scope when debugging in an
2154 instantiation. For example, if you have:
2156 template<int X> int func (void) { return X; }
2158 then if you step into func<5>, "print X" will show "5". This
2159 feature requires proper debuginfo support from the compiler; it
2160 was added to GCC 4.5.
2162 ** The motion commands "next", "finish", "until", and "advance" now
2163 work better when exceptions are thrown. In particular, GDB will
2164 no longer lose control of the inferior; instead, the GDB will
2165 stop the inferior at the point at which the exception is caught.
2166 This functionality requires a change in the exception handling
2167 code that was introduced in GCC 4.5.
2169 * GDB now follows GCC's rules on accessing volatile objects when
2170 reading or writing target state during expression evaluation.
2171 One notable difference to prior behavior is that "print x = 0"
2172 no longer generates a read of x; the value of the assignment is
2173 now always taken directly from the value being assigned.
2175 * GDB now has some support for using labels in the program's source in
2176 linespecs. For instance, you can use "advance label" to continue
2177 execution to a label.
2179 * GDB now has support for reading and writing a new .gdb_index
2180 section. This section holds a fast index of DWARF debugging
2181 information and can be used to greatly speed up GDB startup and
2182 operation. See the documentation for `save gdb-index' for details.
2184 * The "watch" command now accepts an optional "-location" argument.
2185 When used, this causes GDB to watch the memory referred to by the
2186 expression. Such a watchpoint is never deleted due to it going out
2189 * GDB now supports thread debugging of core dumps on GNU/Linux.
2191 GDB now activates thread debugging using the libthread_db library
2192 when debugging GNU/Linux core dumps, similarly to when debugging
2193 live processes. As a result, when debugging a core dump file, GDB
2194 is now able to display pthread_t ids of threads. For example, "info
2195 threads" shows the same output as when debugging the process when it
2196 was live. In earlier releases, you'd see something like this:
2199 * 1 LWP 6780 main () at main.c:10
2201 While now you see this:
2204 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2206 It is also now possible to inspect TLS variables when debugging core
2209 When debugging a core dump generated on a machine other than the one
2210 used to run GDB, you may need to point GDB at the correct
2211 libthread_db library with the "set libthread-db-search-path"
2212 command. See the user manual for more details on this command.
2214 * When natively debugging programs on PowerPC BookE processors running
2215 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2216 which stop execution of the inferior whenever it executes an instruction
2217 at any address within the specified range. See the "PowerPC Embedded"
2218 section in the user manual for more details.
2220 * New features in the GDB remote stub, GDBserver
2222 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2223 and i686 LynxOS (version 5.x).
2225 ** GDBserver is now supported on Blackfin Linux.
2227 * New native configurations
2229 ia64 HP-UX ia64-*-hpux*
2233 Analog Devices, Inc. Blackfin Processor bfin-*
2235 * Ada task switching is now supported on sparc-elf targets when
2236 debugging a program using the Ravenscar Profile. For more information,
2237 see the "Tasking Support when using the Ravenscar Profile" section
2238 in the GDB user manual.
2240 * Guile support was removed.
2242 * New features in the GNU simulator
2244 ** The --map-info flag lists all known core mappings.
2246 ** CFI flashes may be simulated via the "cfi" device.
2248 *** Changes in GDB 7.2
2250 * Shared library support for remote targets by default
2252 When GDB is configured for a generic, non-OS specific target, like
2253 for example, --target=arm-eabi or one of the many *-*-elf targets,
2254 GDB now queries remote stubs for loaded shared libraries using the
2255 `qXfer:libraries:read' packet. Previously, shared library support
2256 was always disabled for such configurations.
2260 ** Argument Dependent Lookup (ADL)
2262 In C++ ADL lookup directs function search to the namespaces of its
2263 arguments even if the namespace has not been imported.
2273 Here the compiler will search for `foo' in the namespace of 'b'
2274 and find A::foo. GDB now supports this. This construct is commonly
2275 used in the Standard Template Library for operators.
2277 ** Improved User Defined Operator Support
2279 In addition to member operators, GDB now supports lookup of operators
2280 defined in a namespace and imported with a `using' directive, operators
2281 defined in the global scope, operators imported implicitly from an
2282 anonymous namespace, and the ADL operators mentioned in the previous
2284 GDB now also supports proper overload resolution for all the previously
2285 mentioned flavors of operators.
2287 ** static const class members
2289 Printing of static const class members that are initialized in the
2290 class definition has been fixed.
2292 * Windows Thread Information Block access.
2294 On Windows targets, GDB now supports displaying the Windows Thread
2295 Information Block (TIB) structure. This structure is visible either
2296 by using the new command `info w32 thread-information-block' or, by
2297 dereferencing the new convenience variable named `$_tlb', a
2298 thread-specific pointer to the TIB. This feature is also supported
2299 when remote debugging using GDBserver.
2301 * Static tracepoints
2303 Static tracepoints are calls in the user program into a tracing
2304 library. One such library is a port of the LTTng kernel tracer to
2305 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2306 When debugging with GDBserver, GDB now supports combining the GDB
2307 tracepoint machinery with such libraries. For example: the user can
2308 use GDB to probe a static tracepoint marker (a call from the user
2309 program into the tracing library) with the new "strace" command (see
2310 "New commands" below). This creates a "static tracepoint" in the
2311 breakpoint list, that can be manipulated with the same feature set
2312 as fast and regular tracepoints. E.g., collect registers, local and
2313 global variables, collect trace state variables, and define
2314 tracepoint conditions. In addition, the user can collect extra
2315 static tracepoint marker specific data, by collecting the new
2316 $_sdata internal variable. When analyzing the trace buffer, you can
2317 inspect $_sdata like any other variable available to GDB. For more
2318 information, see the "Tracepoints" chapter in GDB user manual. New
2319 remote packets have been defined to support static tracepoints, see
2320 the "New remote packets" section below.
2322 * Better reconstruction of tracepoints after disconnected tracing
2324 GDB will attempt to download the original source form of tracepoint
2325 definitions when starting a trace run, and then will upload these
2326 upon reconnection to the target, resulting in a more accurate
2327 reconstruction of the tracepoints that are in use on the target.
2331 You can now exercise direct control over the ways that GDB can
2332 affect your program. For instance, you can disallow the setting of
2333 breakpoints, so that the program can run continuously (assuming
2334 non-stop mode). In addition, the "observer" variable is available
2335 to switch all of the different controls; in observer mode, GDB
2336 cannot affect the target's behavior at all, which is useful for
2337 tasks like diagnosing live systems in the field.
2339 * The new convenience variable $_thread holds the number of the
2342 * New remote packets
2346 Return the address of the Windows Thread Information Block of a given thread.
2350 In response to several of the tracepoint packets, the target may now
2351 also respond with a number of intermediate `qRelocInsn' request
2352 packets before the final result packet, to have GDB handle
2353 relocating an instruction to execute at a different address. This
2354 is particularly useful for stubs that support fast tracepoints. GDB
2355 reports support for this feature in the qSupported packet.
2359 List static tracepoint markers in the target program.
2363 List static tracepoint markers at a given address in the target
2366 qXfer:statictrace:read
2368 Read the static trace data collected (by a `collect $_sdata'
2369 tracepoint action). The remote stub reports support for this packet
2370 to gdb's qSupported query.
2374 Send the current settings of GDB's permission flags.
2378 Send part of the source (textual) form of a tracepoint definition,
2379 which includes location, conditional, and action list.
2381 * The source command now accepts a -s option to force searching for the
2382 script in the source search path even if the script name specifies
2385 * New features in the GDB remote stub, GDBserver
2387 - GDBserver now support tracepoints (including fast tracepoints, and
2388 static tracepoints). The feature is currently supported by the
2389 i386-linux and amd64-linux builds. See the "Tracepoints support
2390 in gdbserver" section in the manual for more information.
2392 GDBserver JIT compiles the tracepoint's conditional agent
2393 expression bytecode into native code whenever possible for low
2394 overhead dynamic tracepoints conditionals. For such tracepoints,
2395 an expression that examines program state is evaluated when the
2396 tracepoint is reached, in order to determine whether to capture
2397 trace data. If the condition is simple and false, processing the
2398 tracepoint finishes very quickly and no data is gathered.
2400 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2401 for static tracepoints support.
2403 - GDBserver now supports x86_64 Windows 64-bit debugging.
2405 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2406 it understands register description.
2408 * The --batch flag now disables pagination and queries.
2410 * X86 general purpose registers
2412 GDB now supports reading/writing byte, word and double-word x86
2413 general purpose registers directly. This means you can use, say,
2414 $ah or $ax to refer, respectively, to the byte register AH and
2415 16-bit word register AX that are actually portions of the 32-bit
2416 register EAX or 64-bit register RAX.
2418 * The `commands' command now accepts a range of breakpoints to modify.
2419 A plain `commands' following a command that creates multiple
2420 breakpoints affects all the breakpoints set by that command. This
2421 applies to breakpoints set by `rbreak', and also applies when a
2422 single `break' command creates multiple breakpoints (e.g.,
2423 breakpoints on overloaded c++ functions).
2425 * The `rbreak' command now accepts a filename specification as part of
2426 its argument, limiting the functions selected by the regex to those
2427 in the specified file.
2429 * Support for remote debugging Windows and SymbianOS shared libraries
2430 from Unix hosts has been improved. Non Windows GDB builds now can
2431 understand target reported file names that follow MS-DOS based file
2432 system semantics, such as file names that include drive letters and
2433 use the backslash character as directory separator. This makes it
2434 possible to transparently use the "set sysroot" and "set
2435 solib-search-path" on Unix hosts to point as host copies of the
2436 target's shared libraries. See the new command "set
2437 target-file-system-kind" described below, and the "Commands to
2438 specify files" section in the user manual for more information.
2442 eval template, expressions...
2443 Convert the values of one or more expressions under the control
2444 of the string template to a command line, and call it.
2446 set target-file-system-kind unix|dos-based|auto
2447 show target-file-system-kind
2448 Set or show the assumed file system kind for target reported file
2451 save breakpoints <filename>
2452 Save all current breakpoint definitions to a file suitable for use
2453 in a later debugging session. To read the saved breakpoint
2454 definitions, use the `source' command.
2456 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2459 info static-tracepoint-markers
2460 Display information about static tracepoint markers in the target.
2462 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2463 Define a static tracepoint by probing a marker at the given
2464 function, line, address, or marker ID.
2468 Enable and disable observer mode.
2470 set may-write-registers on|off
2471 set may-write-memory on|off
2472 set may-insert-breakpoints on|off
2473 set may-insert-tracepoints on|off
2474 set may-insert-fast-tracepoints on|off
2475 set may-interrupt on|off
2476 Set individual permissions for GDB effects on the target. Note that
2477 some of these settings can have undesirable or surprising
2478 consequences, particularly when changed in the middle of a session.
2479 For instance, disabling the writing of memory can prevent
2480 breakpoints from being inserted, cause single-stepping to fail, or
2481 even crash your program, if you disable after breakpoints have been
2482 inserted. However, GDB should not crash.
2484 set record memory-query on|off
2485 show record memory-query
2486 Control whether to stop the inferior if memory changes caused
2487 by an instruction cannot be recorded.
2492 The disassemble command now supports "start,+length" form of two arguments.
2496 ** GDB now provides a new directory location, called the python directory,
2497 where Python scripts written for GDB can be installed. The location
2498 of that directory is <data-directory>/python, where <data-directory>
2499 is the GDB data directory. For more details, see section `Scripting
2500 GDB using Python' in the manual.
2502 ** The GDB Python API now has access to breakpoints, symbols, symbol
2503 tables, program spaces, inferiors, threads and frame's code blocks.
2504 Additionally, GDB Parameters can now be created from the API, and
2505 manipulated via set/show in the CLI.
2507 ** New functions gdb.target_charset, gdb.target_wide_charset,
2508 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2510 ** New exception gdb.GdbError.
2512 ** Pretty-printers are now also looked up in the current program space.
2514 ** Pretty-printers can now be individually enabled and disabled.
2516 ** GDB now looks for names of Python scripts to auto-load in a
2517 special section named `.debug_gdb_scripts', in addition to looking
2518 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2520 * Tracepoint actions were unified with breakpoint commands. In particular,
2521 there are no longer differences in "info break" output for breakpoints and
2522 tracepoints and the "commands" command can be used for both tracepoints and
2523 regular breakpoints.
2527 ARM Symbian arm*-*-symbianelf*
2529 * D language support.
2530 GDB now supports debugging programs written in the D programming
2533 * GDB now supports the extended ptrace interface for PowerPC which is
2534 available since Linux kernel version 2.6.34. This automatically enables
2535 any hardware breakpoints and additional hardware watchpoints available in
2536 the processor. The old ptrace interface exposes just one hardware
2537 watchpoint and no hardware breakpoints.
2539 * GDB is now able to use the Data Value Compare (DVC) register available on
2540 embedded PowerPC processors to implement in hardware simple watchpoint
2541 conditions of the form:
2543 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2545 This works in native GDB running on Linux kernels with the extended ptrace
2546 interface mentioned above.
2548 *** Changes in GDB 7.1
2552 ** Namespace Support
2554 GDB now supports importing of namespaces in C++. This enables the
2555 user to inspect variables from imported namespaces. Support for
2556 namepace aliasing has also been added. So, if a namespace is
2557 aliased in the current scope (e.g. namepace C=A; ) the user can
2558 print variables using the alias (e.g. (gdb) print C::x).
2562 All known bugs relating to the printing of virtual base class were
2563 fixed. It is now possible to call overloaded static methods using a
2568 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2569 and reinterpret_cast<> are now handled by the C++ expression parser.
2573 Xilinx MicroBlaze microblaze-*-*
2578 Xilinx MicroBlaze microblaze
2581 * Multi-program debugging.
2583 GDB now has support for multi-program (a.k.a. multi-executable or
2584 multi-exec) debugging. This allows for debugging multiple inferiors
2585 simultaneously each running a different program under the same GDB
2586 session. See "Debugging Multiple Inferiors and Programs" in the
2587 manual for more information. This implied some user visible changes
2588 in the multi-inferior support. For example, "info inferiors" now
2589 lists inferiors that are not running yet or that have exited
2590 already. See also "New commands" and "New options" below.
2592 * New tracing features
2594 GDB's tracepoint facility now includes several new features:
2596 ** Trace state variables
2598 GDB tracepoints now include support for trace state variables, which
2599 are variables managed by the target agent during a tracing
2600 experiment. They are useful for tracepoints that trigger each
2601 other, so for instance one tracepoint can count hits in a variable,
2602 and then a second tracepoint has a condition that is true when the
2603 count reaches a particular value. Trace state variables share the
2604 $-syntax of GDB convenience variables, and can appear in both
2605 tracepoint actions and condition expressions. Use the "tvariable"
2606 command to create, and "info tvariables" to view; see "Trace State
2607 Variables" in the manual for more detail.
2611 GDB now includes an option for defining fast tracepoints, which
2612 targets may implement more efficiently, such as by installing a jump
2613 into the target agent rather than a trap instruction. The resulting
2614 speedup can be by two orders of magnitude or more, although the
2615 tradeoff is that some program locations on some target architectures
2616 might not allow fast tracepoint installation, for instance if the
2617 instruction to be replaced is shorter than the jump. To request a
2618 fast tracepoint, use the "ftrace" command, with syntax identical to
2619 the regular trace command.
2621 ** Disconnected tracing
2623 It is now possible to detach GDB from the target while it is running
2624 a trace experiment, then reconnect later to see how the experiment
2625 is going. In addition, a new variable disconnected-tracing lets you
2626 tell the target agent whether to continue running a trace if the
2627 connection is lost unexpectedly.
2631 GDB now has the ability to save the trace buffer into a file, and
2632 then use that file as a target, similarly to you can do with
2633 corefiles. You can select trace frames, print data that was
2634 collected in them, and use tstatus to display the state of the
2635 tracing run at the moment that it was saved. To create a trace
2636 file, use "tsave <filename>", and to use it, do "target tfile
2639 ** Circular trace buffer
2641 You can ask the target agent to handle the trace buffer as a
2642 circular buffer, discarding the oldest trace frames to make room for
2643 newer ones, by setting circular-trace-buffer to on. This feature may
2644 not be available for all target agents.
2649 The disassemble command, when invoked with two arguments, now requires
2650 the arguments to be comma-separated.
2653 The info variables command now displays variable definitions. Files
2654 which only declare a variable are not shown.
2657 The source command is now capable of sourcing Python scripts.
2658 This feature is dependent on the debugger being build with Python
2661 Related to this enhancement is also the introduction of a new command
2662 "set script-extension" (see below).
2664 * New commands (for set/show, see "New options" below)
2666 record save [<FILENAME>]
2667 Save a file (in core file format) containing the process record
2668 execution log for replay debugging at a later time.
2670 record restore <FILENAME>
2671 Restore the process record execution log that was saved at an
2672 earlier time, for replay debugging.
2674 add-inferior [-copies <N>] [-exec <FILENAME>]
2677 clone-inferior [-copies <N>] [ID]
2678 Make a new inferior ready to execute the same program another
2679 inferior has loaded.
2684 maint info program-spaces
2685 List the program spaces loaded into GDB.
2687 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2688 show remote interrupt-sequence
2689 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2690 as the sequence to the remote target in order to interrupt the execution.
2691 Ctrl-C is a default. Some system prefers BREAK which is high level of
2692 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2693 Magic SysRq g. It is BREAK signal and character 'g'.
2695 set remote interrupt-on-connect [on | off]
2696 show remote interrupt-on-connect
2697 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2698 remote target when gdb connects to it. This is needed when you debug
2701 set remotebreak [on | off]
2703 Deprecated. Use "set/show remote interrupt-sequence" instead.
2705 tvariable $NAME [ = EXP ]
2706 Create or modify a trace state variable.
2709 List trace state variables and their values.
2711 delete tvariable $NAME ...
2712 Delete one or more trace state variables.
2715 Evaluate the given expressions without collecting anything into the
2716 trace buffer. (Valid in tracepoint actions only.)
2718 ftrace FN / FILE:LINE / *ADDR
2719 Define a fast tracepoint at the given function, line, or address.
2721 * New expression syntax
2723 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2724 GDB now parses 0b101010 identically with 42.
2728 set follow-exec-mode new|same
2729 show follow-exec-mode
2730 Control whether GDB reuses the same inferior across an exec call or
2731 creates a new one. This is useful to be able to restart the old
2732 executable after the inferior having done an exec call.
2734 set default-collect EXPR, ...
2735 show default-collect
2736 Define a list of expressions to be collected at each tracepoint.
2737 This is a useful way to ensure essential items are not overlooked,
2738 such as registers or a critical global variable.
2740 set disconnected-tracing
2741 show disconnected-tracing
2742 If set to 1, the target is instructed to continue tracing if it
2743 loses its connection to GDB. If 0, the target is to stop tracing
2746 set circular-trace-buffer
2747 show circular-trace-buffer
2748 If set to on, the target is instructed to use a circular trace buffer
2749 and discard the oldest trace frames instead of stopping the trace due
2750 to a full trace buffer. If set to off, the trace stops when the buffer
2751 fills up. Some targets may not support this.
2753 set script-extension off|soft|strict
2754 show script-extension
2755 If set to "off", the debugger does not perform any script language
2756 recognition, and all sourced files are assumed to be GDB scripts.
2757 If set to "soft" (the default), files are sourced according to
2758 filename extension, falling back to GDB scripts if the first
2760 If set to "strict", files are sourced according to filename extension.
2762 set ada trust-PAD-over-XVS on|off
2763 show ada trust-PAD-over-XVS
2764 If off, activate a workaround against a bug in the debugging information
2765 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2766 the GCC sources for more information about the GNAT encoding and
2767 PAD types in particular). It is always safe to set this option to
2768 off, but this introduces a slight performance penalty. The default
2771 * Python API Improvements
2773 ** GDB provides the new class gdb.LazyString. This is useful in
2774 some pretty-printing cases. The new method gdb.Value.lazy_string
2775 provides a simple way to create objects of this type.
2777 ** The fields returned by gdb.Type.fields now have an
2778 `is_base_class' attribute.
2780 ** The new method gdb.Type.range returns the range of an array type.
2782 ** The new method gdb.parse_and_eval can be used to parse and
2783 evaluate an expression.
2785 * New remote packets
2788 Define a trace state variable.
2791 Get the current value of a trace state variable.
2794 Set desired tracing behavior upon disconnection.
2797 Set the trace buffer to be linear or circular.
2800 Get data about the tracepoints currently in use.
2804 Process record now works correctly with hardware watchpoints.
2806 Multiple bug fixes have been made to the mips-irix port, making it
2807 much more reliable. In particular:
2808 - Debugging threaded applications is now possible again. Previously,
2809 GDB would hang while starting the program, or while waiting for
2810 the program to stop at a breakpoint.
2811 - Attaching to a running process no longer hangs.
2812 - An error occurring while loading a core file has been fixed.
2813 - Changing the value of the PC register now works again. This fixes
2814 problems observed when using the "jump" command, or when calling
2815 a function from GDB, or even when assigning a new value to $pc.
2816 - With the "finish" and "return" commands, the return value for functions
2817 returning a small array is now correctly printed.
2818 - It is now possible to break on shared library code which gets executed
2819 during a shared library init phase (code executed while executing
2820 their .init section). Previously, the breakpoint would have no effect.
2821 - GDB is now able to backtrace through the signal handler for
2822 non-threaded programs.
2824 PIE (Position Independent Executable) programs debugging is now supported.
2825 This includes debugging execution of PIC (Position Independent Code) shared
2826 libraries although for that, it should be possible to run such libraries as an
2829 *** Changes in GDB 7.0
2831 * GDB now has an interface for JIT compilation. Applications that
2832 dynamically generate code can create symbol files in memory and register
2833 them with GDB. For users, the feature should work transparently, and
2834 for JIT developers, the interface is documented in the GDB manual in the
2835 "JIT Compilation Interface" chapter.
2837 * Tracepoints may now be conditional. The syntax is as for
2838 breakpoints; either an "if" clause appended to the "trace" command,
2839 or the "condition" command is available. GDB sends the condition to
2840 the target for evaluation using the same bytecode format as is used
2841 for tracepoint actions.
2843 * The disassemble command now supports: an optional /r modifier, print the
2844 raw instructions in hex as well as in symbolic form, and an optional /m
2845 modifier to print mixed source+assembly.
2847 * Process record and replay
2849 In a architecture environment that supports ``process record and
2850 replay'', ``process record and replay'' target can record a log of
2851 the process execution, and replay it with both forward and reverse
2854 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2855 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2856 set execution-direction {forward|reverse}, for targets that support
2859 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2860 feature is available with a native GDB running on kernel version
2863 * GDB now has support for multi-byte and wide character sets on the
2864 target. Strings whose character type is wchar_t, char16_t, or
2865 char32_t are now correctly printed. GDB supports wide- and unicode-
2866 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2867 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2868 `printf'. This feature requires iconv to work properly; if your
2869 system does not have a working iconv, GDB can use GNU libiconv. See
2870 the installation instructions for more information.
2872 * GDB now supports automatic retrieval of shared library files from
2873 remote targets. To use this feature, specify a system root that begins
2874 with the `remote:' prefix, either via the `set sysroot' command or via
2875 the `--with-sysroot' configure-time option.
2877 * "info sharedlibrary" now takes an optional regex of libraries to show,
2878 and it now reports if a shared library has no debugging information.
2880 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2881 now complete on file names.
2883 * When completing in expressions, gdb will attempt to limit
2884 completions to allowable structure or union fields, where appropriate.
2885 For instance, consider:
2887 # struct example { int f1; double f2; };
2888 # struct example variable;
2891 If the user types TAB at the end of this command line, the available
2892 completions will be "f1" and "f2".
2894 * Inlined functions are now supported. They show up in backtraces, and
2895 the "step", "next", and "finish" commands handle them automatically.
2897 * GDB now supports the token-splicing (##) and stringification (#)
2898 operators when expanding macros. It also supports variable-arity
2901 * GDB now supports inspecting extra signal information, exported by
2902 the new $_siginfo convenience variable. The feature is currently
2903 implemented on linux ARM, i386 and amd64.
2905 * GDB can now display the VFP floating point registers and NEON vector
2906 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2907 can provide these registers (requires Linux 2.6.30 or later). Remote
2908 and simulator targets may also provide them.
2910 * New remote packets
2913 Search memory for a sequence of bytes.
2916 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2917 operation over reliable transport links. Use of this packet is
2918 controlled by the `set remote noack-packet' command.
2921 Kill the process with the specified process ID. Use this in preference
2922 to `k' when multiprocess protocol extensions are supported.
2925 Obtains additional operating system information
2929 Read or write additional signal information.
2931 * Removed remote protocol undocumented extension
2933 An undocumented extension to the remote protocol's `S' stop reply
2934 packet that permited the stub to pass a process id was removed.
2935 Remote servers should use the `T' stop reply packet instead.
2937 * GDB now supports multiple function calling conventions according to the
2938 DWARF-2 DW_AT_calling_convention function attribute.
2940 * The SH target utilizes the aforementioned change to distinguish between gcc
2941 and Renesas calling convention. It also adds the new CLI commands
2942 `set/show sh calling-convention'.
2944 * GDB can now read compressed debug sections, as produced by GNU gold
2945 with the --compress-debug-sections=zlib flag.
2947 * 64-bit core files are now supported on AIX.
2949 * Thread switching is now supported on Tru64.
2951 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2952 which will be allocated using malloc later in program execution.
2954 * The qXfer:libraries:read remote procotol packet now allows passing a
2955 list of section offsets.
2957 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2958 conditions handling signals delivered during attach or thread creation
2959 have also been fixed.
2961 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2962 From the user's standpoint, all unqualified instances of True and False
2963 are treated as the standard definitions, regardless of context.
2965 * GDB now parses C++ symbol and type names more flexibly. For
2968 template<typename T> class C { };
2971 GDB will now correctly handle all of:
2973 ptype C<char const *>
2974 ptype C<char const*>
2975 ptype C<const char *>
2976 ptype C<const char*>
2978 * New features in the GDB remote stub, gdbserver
2980 - The "--wrapper" command-line argument tells gdbserver to use a
2981 wrapper program to launch programs for debugging.
2983 - On PowerPC and S/390 targets, it is now possible to use a single
2984 gdbserver executable to debug both 32-bit and 64-bit programs.
2985 (This requires gdbserver itself to be built as a 64-bit executable.)
2987 - gdbserver uses the new noack protocol mode for TCP connections to
2988 reduce communications latency, if also supported and enabled in GDB.
2990 - Support for the sparc64-linux-gnu target is now included in
2993 - The amd64-linux build of gdbserver now supports debugging both
2994 32-bit and 64-bit programs.
2996 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2997 now support hardware watchpoints, and will use them automatically
3002 GDB now has support for scripting using Python. Whether this is
3003 available is determined at configure time.
3005 New GDB commands can now be written in Python.
3007 * Ada tasking support
3009 Ada tasks can now be inspected in GDB. The following commands have
3013 Print the list of Ada tasks.
3015 Print detailed information about task number N.
3017 Print the task number of the current task.
3019 Switch the context of debugging to task number N.
3021 * Support for user-defined prefixed commands. The "define" command can
3022 add new commands to existing prefixes, e.g. "target".
3024 * Multi-inferior, multi-process debugging.
3026 GDB now has generalized support for multi-inferior debugging. See
3027 "Debugging Multiple Inferiors" in the manual for more information.
3028 Although availability still depends on target support, the command
3029 set is more uniform now. The GNU/Linux specific multi-forks support
3030 has been migrated to this new framework. This implied some user
3031 visible changes; see "New commands" and also "Removed commands"
3034 * Target descriptions can now describe the target OS ABI. See the
3035 "Target Description Format" section in the user manual for more
3038 * Target descriptions can now describe "compatible" architectures
3039 to indicate that the target can execute applications for a different
3040 architecture in addition to those for the main target architecture.
3041 See the "Target Description Format" section in the user manual for
3044 * Multi-architecture debugging.
3046 GDB now includes general supports for debugging applications on
3047 hybrid systems that use more than one single processor architecture
3048 at the same time. Each such hybrid architecture still requires
3049 specific support to be added. The only hybrid architecture supported
3050 in this version of GDB is the Cell Broadband Engine.
3052 * GDB now supports integrated debugging of Cell/B.E. applications that
3053 use both the PPU and SPU architectures. To enable support for hybrid
3054 Cell/B.E. debugging, you need to configure GDB to support both the
3055 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3056 --enable-targets configure option.
3058 * Non-stop mode debugging.
3060 For some targets, GDB now supports an optional mode of operation in
3061 which you can examine stopped threads while other threads continue
3062 to execute freely. This is referred to as non-stop mode, with the
3063 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3064 section in the user manual for more information.
3066 To be able to support remote non-stop debugging, a remote stub needs
3067 to implement the non-stop mode remote protocol extensions, as
3068 described in the "Remote Non-Stop" section of the user manual. The
3069 GDB remote stub, gdbserver, has been adjusted to support these
3070 extensions on linux targets.
3072 * New commands (for set/show, see "New options" below)
3074 catch syscall [NAME(S) | NUMBER(S)]
3075 Catch system calls. Arguments, which should be names of system
3076 calls or their numbers, mean catch only those syscalls. Without
3077 arguments, every syscall will be caught. When the inferior issues
3078 any of the specified syscalls, GDB will stop and announce the system
3079 call, both when it is called and when its call returns. This
3080 feature is currently available with a native GDB running on the
3081 Linux Kernel, under the following architectures: x86, x86_64,
3082 PowerPC and PowerPC64.
3084 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3086 Search memory for a sequence of bytes.
3088 maint set python print-stack
3089 maint show python print-stack
3090 Show a stack trace when an error is encountered in a Python script.
3093 Invoke CODE by passing it to the Python interpreter.
3098 These allow macros to be defined, undefined, and listed
3102 Show operating system information about processes.
3105 List the inferiors currently under GDB's control.
3108 Switch focus to inferior number NUM.
3111 Detach from inferior number NUM.
3114 Kill inferior number NUM.
3118 set spu stop-on-load
3119 show spu stop-on-load
3120 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3122 set spu auto-flush-cache
3123 show spu auto-flush-cache
3124 Control whether to automatically flush the software-managed cache
3125 during Cell/B.E. debugging.
3127 set sh calling-convention
3128 show sh calling-convention
3129 Control the calling convention used when calling SH target functions.
3132 show debug timestamp
3133 Control display of timestamps with GDB debugging output.
3135 set disassemble-next-line
3136 show disassemble-next-line
3137 Control display of disassembled source lines or instructions when
3140 set remote noack-packet
3141 show remote noack-packet
3142 Set/show the use of remote protocol QStartNoAckMode packet. See above
3143 under "New remote packets."
3145 set remote query-attached-packet
3146 show remote query-attached-packet
3147 Control use of remote protocol `qAttached' (query-attached) packet.
3149 set remote read-siginfo-object
3150 show remote read-siginfo-object
3151 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3154 set remote write-siginfo-object
3155 show remote write-siginfo-object
3156 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3159 set remote reverse-continue
3160 show remote reverse-continue
3161 Control use of remote protocol 'bc' (reverse-continue) packet.
3163 set remote reverse-step
3164 show remote reverse-step
3165 Control use of remote protocol 'bs' (reverse-step) packet.
3167 set displaced-stepping
3168 show displaced-stepping
3169 Control displaced stepping mode. Displaced stepping is a way to
3170 single-step over breakpoints without removing them from the debuggee.
3171 Also known as "out-of-line single-stepping".
3174 show debug displaced
3175 Control display of debugging info for displaced stepping.
3177 maint set internal-error
3178 maint show internal-error
3179 Control what GDB does when an internal error is detected.
3181 maint set internal-warning
3182 maint show internal-warning
3183 Control what GDB does when an internal warning is detected.
3188 Use a wrapper program to launch programs for debugging.
3190 set multiple-symbols (all|ask|cancel)
3191 show multiple-symbols
3192 The value of this variable can be changed to adjust the debugger behavior
3193 when an expression or a breakpoint location contains an ambiguous symbol
3194 name (an overloaded function name, for instance).
3196 set breakpoint always-inserted
3197 show breakpoint always-inserted
3198 Keep breakpoints always inserted in the target, as opposed to inserting
3199 them when resuming the target, and removing them when the target stops.
3200 This option can improve debugger performance on slow remote targets.
3202 set arm fallback-mode (arm|thumb|auto)
3203 show arm fallback-mode
3204 set arm force-mode (arm|thumb|auto)
3206 These commands control how ARM GDB determines whether instructions
3207 are ARM or Thumb. The default for both settings is auto, which uses
3208 the current CPSR value for instructions without symbols; previous
3209 versions of GDB behaved as if "set arm fallback-mode arm".
3211 set disable-randomization
3212 show disable-randomization
3213 Standalone programs run with the virtual address space randomization enabled
3214 by default on some platforms. This option keeps the addresses stable across
3215 multiple debugging sessions.
3219 Control whether other threads are stopped or not when some thread hits
3224 Requests that asynchronous execution is enabled in the target, if available.
3225 In this case, it's possible to resume target in the background, and interact
3226 with GDB while the target is running. "show target-async" displays the
3227 current state of asynchronous execution of the target.
3229 set target-wide-charset
3230 show target-wide-charset
3231 The target-wide-charset is the name of the character set that GDB
3232 uses when printing characters whose type is wchar_t.
3234 set tcp auto-retry (on|off)
3236 set tcp connect-timeout
3237 show tcp connect-timeout
3238 These commands allow GDB to retry failed TCP connections to a remote stub
3239 with a specified timeout period; this is useful if the stub is launched
3240 in parallel with GDB but may not be ready to accept connections immediately.
3242 set libthread-db-search-path
3243 show libthread-db-search-path
3244 Control list of directories which GDB will search for appropriate
3247 set schedule-multiple (on|off)
3248 show schedule-multiple
3249 Allow GDB to resume all threads of all processes or only threads of
3250 the current process.
3254 Use more aggressive caching for accesses to the stack. This improves
3255 performance of remote debugging (particularly backtraces) without
3256 affecting correctness.
3258 set interactive-mode (on|off|auto)
3259 show interactive-mode
3260 Control whether GDB runs in interactive mode (on) or not (off).
3261 When in interactive mode, GDB waits for the user to answer all
3262 queries. Otherwise, GDB does not wait and assumes the default
3263 answer. When set to auto (the default), GDB determines which
3264 mode to use based on the stdin settings.
3269 For program forks, this is replaced by the new more generic `info
3270 inferiors' command. To list checkpoints, you can still use the
3271 `info checkpoints' command, which was an alias for the `info forks'
3275 Replaced by the new `inferior' command. To switch between
3276 checkpoints, you can still use the `restart' command, which was an
3277 alias for the `fork' command.
3280 This is removed, since some targets don't have a notion of
3281 processes. To switch between processes, you can still use the
3282 `inferior' command using GDB's own inferior number.
3285 For program forks, this is replaced by the new more generic `kill
3286 inferior' command. To delete a checkpoint, you can still use the
3287 `delete checkpoint' command, which was an alias for the `delete
3291 For program forks, this is replaced by the new more generic `detach
3292 inferior' command. To detach a checkpoint, you can still use the
3293 `detach checkpoint' command, which was an alias for the `detach
3296 * New native configurations
3298 x86/x86_64 Darwin i[34567]86-*-darwin*
3300 x86_64 MinGW x86_64-*-mingw*
3304 Lattice Mico32 lm32-*
3305 x86 DICOS i[34567]86-*-dicos*
3306 x86_64 DICOS x86_64-*-dicos*
3309 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3310 (mingw32ce) debugging.
3316 These commands were actually not implemented on any target.
3318 *** Changes in GDB 6.8
3320 * New native configurations
3322 NetBSD/hppa hppa*-*netbsd*
3323 Xtensa GNU/Linux xtensa*-*-linux*
3327 NetBSD/hppa hppa*-*-netbsd*
3328 Xtensa GNU/Lunux xtensa*-*-linux*
3330 * Change in command line behavior -- corefiles vs. process ids.
3332 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3333 attaching to process NUMBER fails, GDB no longer attempts to open a
3334 core file named NUMBER. Attaching to a program using the -c option
3335 is no longer supported. Instead, use the '-p' or '--pid' options.
3337 * GDB can now be built as a native debugger for debugging Windows x86
3338 (mingw32) Portable Executable (PE) programs.
3340 * Pending breakpoints no longer change their number when their address
3343 * GDB now supports breakpoints with multiple locations,
3344 including breakpoints on C++ constructors, inside C++ templates,
3345 and in inlined functions.
3347 * GDB's ability to debug optimized code has been improved. GDB more
3348 accurately identifies function bodies and lexical blocks that occupy
3349 more than one contiguous range of addresses.
3351 * Target descriptions can now describe registers for PowerPC.
3353 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3354 registers on PowerPC targets.
3356 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3357 targets even when the libthread_db library is not available.
3359 * The GDB remote stub, gdbserver, now supports the new file transfer
3360 commands (remote put, remote get, and remote delete).
3362 * The GDB remote stub, gdbserver, now supports run and attach in
3363 extended-remote mode.
3365 * hppa*64*-*-hpux11* target broken
3366 The debugger is unable to start a program and fails with the following
3367 error: "Error trying to get information about dynamic linker".
3368 The gdb-6.7 release is also affected.
3370 * GDB now supports the --enable-targets= configure option to allow
3371 building a single GDB executable that supports multiple remote
3372 target architectures.
3374 * GDB now supports debugging C and C++ programs which use the
3375 Decimal Floating Point extension. In addition, the PowerPC target
3376 now has a set of pseudo-registers to inspect decimal float values
3377 stored in two consecutive float registers.
3379 * The -break-insert MI command can optionally create pending
3382 * Improved support for debugging Ada
3383 Many improvements to the Ada language support have been made. These
3385 - Better support for Ada2005 interface types
3386 - Improved handling of arrays and slices in general
3387 - Better support for Taft-amendment types
3388 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3390 - Improved command completion in Ada
3393 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3398 set print frame-arguments (all|scalars|none)
3399 show print frame-arguments
3400 The value of this variable can be changed to control which argument
3401 values should be printed by the debugger when displaying a frame.
3406 Transfer files to and from a remote target, and delete remote files.
3413 Transfer files to and from a remote target, and delete remote files.
3415 * New remote packets
3422 Open, close, read, write, and delete files on the remote system.
3425 Attach to an existing process on the remote system, in extended-remote
3429 Run a new process on the remote system, in extended-remote mode.
3431 *** Changes in GDB 6.7
3433 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3434 bfd, libiberty and opcodes, as revealed by static analysis donated by
3435 Coverity, Inc. (http://scan.coverity.com).
3437 * When looking up multiply-defined global symbols, GDB will now prefer the
3438 symbol definition in the current shared library if it was built using the
3439 -Bsymbolic linker option.
3441 * When the Text User Interface (TUI) is not configured, GDB will now
3442 recognize the -tui command-line option and print a message that the TUI
3445 * The GDB remote stub, gdbserver, now has lower overhead for high
3446 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3448 * GDB for MIPS targets now autodetects whether a remote target provides
3449 32-bit or 64-bit register values.
3451 * Support for C++ member pointers has been improved.
3453 * GDB now understands XML target descriptions, which specify the
3454 target's overall architecture. GDB can read a description from
3455 a local file or over the remote serial protocol.
3457 * Vectors of single-byte data use a new integer type which is not
3458 automatically displayed as character or string data.
3460 * The /s format now works with the print command. It displays
3461 arrays of single-byte integers and pointers to single-byte integers
3464 * Target descriptions can now describe target-specific registers,
3465 for architectures which have implemented the support (currently
3466 only ARM, M68K, and MIPS).
3468 * GDB and the GDB remote stub, gdbserver, now support the XScale
3471 * The GDB remote stub, gdbserver, has been updated to support
3472 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3473 has been rewritten to use the standard GDB remote protocol.
3475 * GDB can now step into C++ functions which are called through thunks.
3477 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3479 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3480 layout. It also supports a TextSeg= and DataSeg= response when only
3481 segment base addresses (rather than offsets) are available.
3483 * The /i format now outputs any trailing branch delay slot instructions
3484 immediately following the last instruction within the count specified.
3486 * The GDB remote protocol "T" stop reply packet now supports a
3487 "library" response. Combined with the new "qXfer:libraries:read"
3488 packet, this response allows GDB to debug shared libraries on targets
3489 where the operating system manages the list of loaded libraries (e.g.
3490 Windows and SymbianOS).
3492 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3493 (DLLs) on Windows and Windows CE targets.
3495 * GDB now supports a faster verification that a .debug file matches its binary
3496 according to its build-id signature, if the signature is present.
3502 Enable or disable hardware flow control (RTS/CTS) on the serial port
3503 when debugging using remote targets.
3505 set mem inaccessible-by-default
3506 show mem inaccessible-by-default
3507 If the target supplies a memory map, for instance via the remote
3508 protocol's "qXfer:memory-map:read" packet, setting this variable
3509 prevents GDB from accessing memory outside the memory map. This
3510 is useful for targets with memory mapped registers or which react
3511 badly to accesses of unmapped address space.
3513 set breakpoint auto-hw
3514 show breakpoint auto-hw
3515 If the target supplies a memory map, for instance via the remote
3516 protocol's "qXfer:memory-map:read" packet, setting this variable
3517 lets GDB use hardware breakpoints automatically for memory regions
3518 where it can not use software breakpoints. This covers both the
3519 "break" command and internal breakpoints used for other commands
3520 including "next" and "finish".
3523 catch exception unhandled
3524 Stop the program execution when Ada exceptions are raised.
3527 Stop the program execution when an Ada assertion failed.
3531 Set an alternate system root for target files. This is a more
3532 general version of "set solib-absolute-prefix", which is now
3533 an alias to "set sysroot".
3536 Provide extended SPU facility status information. This set of
3537 commands is available only when debugging the Cell/B.E. SPU
3540 * New native configurations
3542 OpenBSD/sh sh*-*openbsd*
3545 unset tdesc filename
3547 Use the specified local file as an XML target description, and do
3548 not query the target for its built-in description.
3552 OpenBSD/sh sh*-*-openbsd*
3553 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3554 Toshiba Media Processor mep-elf
3556 * New remote packets
3559 Ignore the specified signals; pass them directly to the debugged program
3560 without stopping other threads or reporting them to GDB.
3562 qXfer:features:read:
3563 Read an XML target description from the target, which describes its
3568 Read or write contents of an spufs file on the target system. These
3569 packets are available only on the Cell/B.E. SPU architecture.
3571 qXfer:libraries:read:
3572 Report the loaded shared libraries. Combined with new "T" packet
3573 response, this packet allows GDB to debug shared libraries on
3574 targets where the operating system manages the list of loaded
3575 libraries (e.g. Windows and SymbianOS).
3579 Support for these obsolete configurations has been removed.
3587 i[34567]86-*-lynxos*
3588 i[34567]86-*-netware*
3589 i[34567]86-*-sco3.2v5*
3590 i[34567]86-*-sco3.2v4*
3592 i[34567]86-*-sysv4.2*
3595 i[34567]86-*-unixware2*
3596 i[34567]86-*-unixware*
3605 * Other removed features
3612 Various m68k-only ROM monitors.
3619 Various Renesas ROM monitors and debugging interfaces for SH and
3624 Support for a Macraigor serial interface to on-chip debugging.
3625 GDB does not directly support the newer parallel or USB
3630 A debug information format. The predecessor to DWARF 2 and
3631 DWARF 3, which are still supported.
3633 Support for the HP aCC compiler on HP-UX/PA-RISC
3635 SOM-encapsulated symbolic debugging information, automatic
3636 invocation of pxdb, and the aCC custom C++ ABI. This does not
3637 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3638 with aCC can still be debugged on an assembly level.
3640 MIPS ".pdr" sections
3642 A MIPS-specific format used to describe stack frame layout
3643 in debugging information.
3647 GDB could work with an older version of Guile to debug
3648 the interpreter and Scheme programs running in it.
3650 set mips stack-arg-size
3651 set mips saved-gpreg-size
3653 Use "set mips abi" to control parameter passing for MIPS.
3655 *** Changes in GDB 6.6
3660 Cell Broadband Engine SPU spu-elf
3662 * GDB can now be configured as a cross-debugger targeting native Windows
3663 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3664 running on a Windows system over TCP/IP to debug Windows programs.
3666 * The GDB remote stub, gdbserver, has been updated to support Windows and
3667 Cygwin debugging. Both single-threaded and multi-threaded programs are
3670 * The "set trust-readonly-sections" command works again. This command was
3671 broken in GDB 6.3, 6.4, and 6.5.
3673 * The "load" command now supports writing to flash memory, if the remote
3674 stub provides the required support.
3676 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3677 longer requires symbolic debug information (e.g. DWARF-2).
3682 unset substitute-path
3683 show substitute-path
3684 Manage a list of substitution rules that GDB uses to rewrite the name
3685 of the directories where the sources are located. This can be useful
3686 for instance when the sources were moved to a different location
3687 between compilation and debugging.
3691 Print each CLI command as it is executed. Each command is prefixed with
3692 a number of `+' symbols representing the nesting depth.
3693 The source command now has a `-v' option to enable the same feature.
3697 The ARM Demon monitor support (RDP protocol, "target rdp").
3699 Kernel Object Display, an embedded debugging feature which only worked with
3700 an obsolete version of Cisco IOS.
3702 The 'set download-write-size' and 'show download-write-size' commands.
3704 * New remote packets
3707 Tell a stub about GDB client features, and request remote target features.
3708 The first feature implemented is PacketSize, which allows the target to
3709 specify the size of packets it can handle - to minimize the number of
3710 packets required and improve performance when connected to a remote
3714 Fetch an OS auxilliary vector from the remote stub. This packet is a
3715 more efficient replacement for qPart:auxv:read.
3717 qXfer:memory-map:read:
3718 Fetch a memory map from the remote stub, including information about
3719 RAM, ROM, and flash memory devices.
3724 Erase and program a flash memory device.
3726 * Removed remote packets
3729 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3730 used it, and only gdbserver implemented it.
3732 *** Changes in GDB 6.5
3736 Renesas M32C/M16C m32c-elf
3738 Morpho Technologies ms1 ms1-elf
3742 init-if-undefined Initialize a convenience variable, but
3743 only if it doesn't already have a value.
3745 The following commands are presently only implemented for native GNU/Linux:
3747 checkpoint Save a snapshot of the program state.
3749 restart <n> Return the program state to a
3750 previously saved state.
3752 info checkpoints List currently saved checkpoints.
3754 delete-checkpoint <n> Delete a previously saved checkpoint.
3756 set|show detach-on-fork Tell gdb whether to detach from a newly
3757 forked process, or to keep debugging it.
3759 info forks List forks of the user program that
3760 are available to be debugged.
3762 fork <n> Switch to debugging one of several
3763 forks of the user program that are
3764 available to be debugged.
3766 delete-fork <n> Delete a fork from the list of forks
3767 that are available to be debugged (and
3768 kill the forked process).
3770 detach-fork <n> Delete a fork from the list of forks
3771 that are available to be debugged (and
3772 allow the process to continue).
3776 Morpho Technologies ms2 ms1-elf
3778 * Improved Windows host support
3780 GDB now builds as a cross debugger hosted on i686-mingw32, including
3781 native console support, and remote communications using either
3782 network sockets or serial ports.
3784 * Improved Modula-2 language support
3786 GDB can now print most types in the Modula-2 syntax. This includes:
3787 basic types, set types, record types, enumerated types, range types,
3788 pointer types and ARRAY types. Procedure var parameters are correctly
3789 printed and hexadecimal addresses and character constants are also
3790 written in the Modula-2 syntax. Best results can be obtained by using
3791 GNU Modula-2 together with the -gdwarf-2 command line option.
3795 The ARM rdi-share module.
3797 The Netware NLM debug server.
3799 *** Changes in GDB 6.4
3801 * New native configurations
3803 OpenBSD/arm arm*-*-openbsd*
3804 OpenBSD/mips64 mips64-*-openbsd*
3808 Morpho Technologies ms1 ms1-elf
3810 * New command line options
3812 --batch-silent As for --batch, but totally silent.
3813 --return-child-result The debugger will exist with the same value
3814 the child (debugged) program exited with.
3815 --eval-command COMMAND, -ex COMMAND
3816 Execute a single GDB CLI command. This may be
3817 specified multiple times and in conjunction
3818 with the --command (-x) option.
3820 * Deprecated commands removed
3822 The following commands, that were deprecated in 2000, have been
3826 set|show arm disassembly-flavor set|show arm disassembler
3827 othernames set arm disassembler
3828 set|show remotedebug set|show debug remote
3829 set|show archdebug set|show debug arch
3830 set|show eventdebug set|show debug event
3833 * New BSD user-level threads support
3835 It is now possible to debug programs using the user-level threads
3836 library on OpenBSD and FreeBSD. Currently supported (target)
3839 FreeBSD/amd64 x86_64-*-freebsd*
3840 FreeBSD/i386 i386-*-freebsd*
3841 OpenBSD/i386 i386-*-openbsd*
3843 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3844 are not yet supported.
3846 * New support for Matsushita MN10300 w/sim added
3847 (Work in progress). mn10300-elf.
3849 * REMOVED configurations and files
3851 VxWorks and the XDR protocol *-*-vxworks
3852 Motorola MCORE mcore-*-*
3853 National Semiconductor NS32000 ns32k-*-*
3855 * New "set print array-indexes" command
3857 After turning this setting "on", GDB prints the index of each element
3858 when displaying arrays. The default is "off" to preserve the previous
3861 * VAX floating point support
3863 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3865 * User-defined command support
3867 In addition to using $arg0..$arg9 for argument passing, it is now possible
3868 to use $argc to determine now many arguments have been passed. See the
3869 section on user-defined commands in the user manual for more information.
3871 *** Changes in GDB 6.3:
3873 * New command line option
3875 GDB now accepts -l followed by a number to set the timeout for remote
3878 * GDB works with GCC -feliminate-dwarf2-dups
3880 GDB now supports a more compact representation of DWARF-2 debug
3881 information using DW_FORM_ref_addr references. These are produced
3882 by GCC with the option -feliminate-dwarf2-dups and also by some
3883 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3884 to use -feliminate-dwarf2-dups.
3886 * Internationalization
3888 When supported by the host system, GDB will be built with
3889 internationalization (libintl). The task of marking up the sources is
3890 continued, we're looking forward to our first translation.
3894 Initial support for debugging programs compiled with the GNAT
3895 implementation of the Ada programming language has been integrated
3896 into GDB. In this release, support is limited to expression evaluation.
3898 * New native configurations
3900 GNU/Linux/m32r m32r-*-linux-gnu
3904 GDB's remote protocol now includes support for the 'p' packet. This
3905 packet is used to fetch individual registers from a remote inferior.
3907 * END-OF-LIFE registers[] compatibility module
3909 GDB's internal register infrastructure has been completely rewritten.
3910 The new infrastructure making possible the implementation of key new
3911 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3914 GDB 6.3 will be the last release to include the the registers[]
3915 compatibility module that allowed out-of-date configurations to
3916 continue to work. This change directly impacts the following
3926 powerpc bdm protocol
3928 Unless there is activity to revive these configurations, they will be
3929 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3931 * OBSOLETE configurations and files
3933 Configurations that have been declared obsolete in this release have
3934 been commented out. Unless there is activity to revive these
3935 configurations, the next release of GDB will have their sources
3936 permanently REMOVED.
3945 *** Changes in GDB 6.2.1:
3947 * MIPS `break main; run' gave an heuristic-fence-post warning
3949 When attempting to run even a simple program, a warning about
3950 heuristic-fence-post being hit would be reported. This problem has
3953 * MIPS IRIX 'long double' crashed GDB
3955 When examining a long double variable, GDB would get a segmentation
3956 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3957 IRIX long double values).
3961 A bug in the VAX stack code was causing problems with the "next"
3962 command. This problem has been fixed.
3964 *** Changes in GDB 6.2:
3966 * Fix for ``many threads''
3968 On GNU/Linux systems that use the NPTL threads library, a program
3969 rapidly creating and deleting threads would confuse GDB leading to the
3972 ptrace: No such process.
3973 thread_db_get_info: cannot get thread info: generic error
3975 This problem has been fixed.
3977 * "-async" and "-noasync" options removed.
3979 Support for the broken "-noasync" option has been removed (it caused
3982 * New ``start'' command.
3984 This command runs the program until the begining of the main procedure.
3986 * New BSD Kernel Data Access Library (libkvm) interface
3988 Using ``target kvm'' it is now possible to debug kernel core dumps and
3989 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3990 platforms. Currently supported (native-only) configurations are:
3992 FreeBSD/amd64 x86_64-*-freebsd*
3993 FreeBSD/i386 i?86-*-freebsd*
3994 NetBSD/i386 i?86-*-netbsd*
3995 NetBSD/m68k m68*-*-netbsd*
3996 NetBSD/sparc sparc-*-netbsd*
3997 OpenBSD/amd64 x86_64-*-openbsd*
3998 OpenBSD/i386 i?86-*-openbsd*
3999 OpenBSD/m68k m68*-openbsd*
4000 OpenBSD/sparc sparc-*-openbsd*
4002 * Signal trampoline code overhauled
4004 Many generic problems with GDB's signal handling code have been fixed.
4005 These include: backtraces through non-contiguous stacks; recognition
4006 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4007 call; backtrace through a signal trampoline; step into and out of
4008 signal handlers; and single-stepping in the signal trampoline.
4010 Please note that kernel bugs are a limiting factor here. These
4011 features have been shown to work on an s390 GNU/Linux system that
4012 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4014 * Cygwin support for DWARF 2 added.
4016 * New native configurations
4018 GNU/Linux/hppa hppa*-*-linux*
4019 OpenBSD/hppa hppa*-*-openbsd*
4020 OpenBSD/m68k m68*-*-openbsd*
4021 OpenBSD/m88k m88*-*-openbsd*
4022 OpenBSD/powerpc powerpc-*-openbsd*
4023 NetBSD/vax vax-*-netbsd*
4024 OpenBSD/vax vax-*-openbsd*
4026 * END-OF-LIFE frame compatibility module
4028 GDB's internal frame infrastructure has been completely rewritten.
4029 The new infrastructure making it possible to support key new features
4030 including DWARF 2 Call Frame Information. To aid in the task of
4031 migrating old configurations to this new infrastructure, a
4032 compatibility module, that allowed old configurations to continue to
4033 work, was also included.
4035 GDB 6.2 will be the last release to include this frame compatibility
4036 module. This change directly impacts the following configurations:
4046 Unless there is activity to revive these configurations, they will be
4047 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4049 * REMOVED configurations and files
4051 Sun 3, running SunOS 3 m68*-*-sunos3*
4052 Sun 3, running SunOS 4 m68*-*-sunos4*
4053 Sun 2, running SunOS 3 m68000-*-sunos3*
4054 Sun 2, running SunOS 4 m68000-*-sunos4*
4055 Motorola 680x0 running LynxOS m68*-*-lynxos*
4056 AT&T 3b1/Unix pc m68*-att-*
4057 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4058 decstation mips-dec-* mips-little-*
4059 riscos mips-*-riscos* mips-*-sysv*
4060 sonymips mips-sony-*
4061 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4063 *** Changes in GDB 6.1.1:
4065 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4067 The TUI (Text-mode User Interface) is now built as part of a default
4068 GDB configuration. It is enabled by either selecting the TUI with the
4069 command line option "-i=tui" or by running the separate "gdbtui"
4070 program. For more information on the TUI, see the manual "Debugging
4073 * Pending breakpoint support (also included in GDB 6.1)
4075 Support has been added to allow you to specify breakpoints in shared
4076 libraries that have not yet been loaded. If a breakpoint location
4077 cannot be found, and the "breakpoint pending" option is set to auto,
4078 GDB queries you if you wish to make the breakpoint pending on a future
4079 shared-library load. If and when GDB resolves the breakpoint symbol,
4080 the pending breakpoint is removed as one or more regular breakpoints
4083 Pending breakpoints are very useful for GCJ Java debugging.
4085 * Fixed ISO-C build problems
4087 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4088 non ISO-C code that stopped them being built using a more strict ISO-C
4089 compiler (e.g., IBM's C compiler).
4091 * Fixed build problem on IRIX 5
4093 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4094 wasn't able to compile compile on an IRIX 5 system.
4096 * Added execute permission to gdb/gdbserver/configure
4098 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4099 permission. This bug would cause configure to fail on a number of
4100 systems (Solaris, IRIX). Ref: server/519.
4102 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4104 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4105 has been updated to use constant array sizes.
4107 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4109 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4110 its generated DWARF Call Frame Info. This encoding was causing GDB to
4111 panic, that panic has been fixed. Ref: gdb/1628.
4113 * Fixed a problem when examining parameters in shared library code.
4115 When examining parameters in optimized shared library code generated
4116 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4117 not available''. GDB now correctly displays the variable's value.
4119 *** Changes in GDB 6.1:
4121 * Removed --with-mmalloc
4123 Support for the mmalloc memory manager has been removed, as it
4124 conflicted with the internal gdb byte cache.
4126 * Changes in AMD64 configurations
4128 The AMD64 target now includes the %cs and %ss registers. As a result
4129 the AMD64 remote protocol has changed; this affects the floating-point
4130 and SSE registers. If you rely on those registers for your debugging,
4131 you should upgrade gdbserver on the remote side.
4133 * Revised SPARC target
4135 The SPARC target has been completely revised, incorporating the
4136 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4137 support for LynxOS and SunOS 4 has been dropped. Calling functions
4138 from within GDB on operating systems with a non-executable stack
4139 (Solaris, OpenBSD) now works.
4143 GDB has a new C++ demangler which does a better job on the mangled
4144 names generated by current versions of g++. It also runs faster, so
4145 with this and other changes gdb should now start faster on large C++
4148 * DWARF 2 Location Expressions
4150 GDB support for location expressions has been extended to support function
4151 arguments and frame bases. Older versions of GDB could crash when they
4154 * C++ nested types and namespaces
4156 GDB's support for nested types and namespaces in C++ has been
4157 improved, especially if you use the DWARF 2 debugging format. (This
4158 is the default for recent versions of GCC on most platforms.)
4159 Specifically, if you have a class "Inner" defined within a class or
4160 namespace "Outer", then GDB realizes that the class's name is
4161 "Outer::Inner", not simply "Inner". This should greatly reduce the
4162 frequency of complaints about not finding RTTI symbols. In addition,
4163 if you are stopped at inside of a function defined within a namespace,
4164 GDB modifies its name lookup accordingly.
4166 * New native configurations
4168 NetBSD/amd64 x86_64-*-netbsd*
4169 OpenBSD/amd64 x86_64-*-openbsd*
4170 OpenBSD/alpha alpha*-*-openbsd*
4171 OpenBSD/sparc sparc-*-openbsd*
4172 OpenBSD/sparc64 sparc64-*-openbsd*
4174 * New debugging protocols
4176 M32R with SDI protocol m32r-*-elf*
4178 * "set prompt-escape-char" command deleted.
4180 The command "set prompt-escape-char" has been deleted. This command,
4181 and its very obscure effet on GDB's prompt, was never documented,
4182 tested, nor mentioned in the NEWS file.
4184 * OBSOLETE configurations and files
4186 Configurations that have been declared obsolete in this release have
4187 been commented out. Unless there is activity to revive these
4188 configurations, the next release of GDB will have their sources
4189 permanently REMOVED.
4191 Sun 3, running SunOS 3 m68*-*-sunos3*
4192 Sun 3, running SunOS 4 m68*-*-sunos4*
4193 Sun 2, running SunOS 3 m68000-*-sunos3*
4194 Sun 2, running SunOS 4 m68000-*-sunos4*
4195 Motorola 680x0 running LynxOS m68*-*-lynxos*
4196 AT&T 3b1/Unix pc m68*-att-*
4197 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4198 decstation mips-dec-* mips-little-*
4199 riscos mips-*-riscos* mips-*-sysv*
4200 sonymips mips-sony-*
4201 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4203 * REMOVED configurations and files
4205 SGI Irix-4.x mips-sgi-irix4 or iris4
4206 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4207 Z8000 simulator z8k-zilog-none or z8ksim
4208 Matsushita MN10200 w/simulator mn10200-*-*
4209 H8/500 simulator h8500-hitachi-hms or h8500hms
4210 HP/PA running BSD hppa*-*-bsd*
4211 HP/PA running OSF/1 hppa*-*-osf*
4212 HP/PA Pro target hppa*-*-pro*
4213 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4214 386BSD i[3456]86-*-bsd*
4215 Sequent family i[3456]86-sequent-sysv4*
4216 i[3456]86-sequent-sysv*
4217 i[3456]86-sequent-bsd*
4218 SPARC running LynxOS sparc-*-lynxos*
4219 SPARC running SunOS 4 sparc-*-sunos4*
4220 Tsqware Sparclet sparclet-*-*
4221 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4223 *** Changes in GDB 6.0:
4227 Support for debugging the Objective-C programming language has been
4228 integrated into GDB.
4230 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4232 DWARF 2's Call Frame Information makes available compiler generated
4233 information that more exactly describes the program's run-time stack.
4234 By using this information, GDB is able to provide more robust stack
4237 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4238 have been updated to use a new backtrace mechanism which includes
4239 DWARF 2 CFI support.
4243 GDB's remote protocol has been extended to include support for hosted
4244 file I/O (where the remote target uses GDB's file system). See GDB's
4245 remote protocol documentation for details.
4247 * All targets using the new architecture framework.
4249 All of GDB's targets have been updated to use the new internal
4250 architecture framework. The way is now open for future GDB releases
4251 to include cross-architecture native debugging support (i386 on amd64,
4254 * GNU/Linux's Thread Local Storage (TLS)
4256 GDB now includes support for for the GNU/Linux implementation of
4257 per-thread variables.
4259 * GNU/Linux's Native POSIX Thread Library (NPTL)
4261 GDB's thread code has been updated to work with either the new
4262 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4264 * Separate debug info.
4266 GDB, in conjunction with BINUTILS, now supports a mechanism for
4267 automatically loading debug information from a separate file. Instead
4268 of shipping full debug and non-debug versions of system libraries,
4269 system integrators can now instead ship just the stripped libraries
4270 and optional debug files.
4272 * DWARF 2 Location Expressions
4274 DWARF 2 Location Expressions allow the compiler to more completely
4275 describe the location of variables (even in optimized code) to the
4278 GDB now includes preliminary support for location expressions (support
4279 for DW_OP_piece is still missing).
4283 A number of long standing bugs that caused GDB to die while starting a
4284 Java application have been fixed. GDB's Java support is now
4285 considered "useable".
4287 * GNU/Linux support for fork, vfork, and exec.
4289 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4290 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4293 * GDB supports logging output to a file
4295 There are two new commands, "set logging" and "show logging", which can be
4296 used to capture GDB's output to a file.
4298 * The meaning of "detach" has changed for gdbserver
4300 The "detach" command will now resume the application, as documented. To
4301 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4304 * d10v, m68hc11 `regs' command deprecated
4306 The `info registers' command has been updated so that it displays the
4307 registers using a format identical to the old `regs' command.
4311 A new command, "maint set profile on/off", has been added. This command can
4312 be used to enable or disable profiling while running GDB, to profile a
4313 session or a set of commands. In addition there is a new configure switch,
4314 "--enable-profiling", which will cause GDB to be compiled with profiling
4315 data, for more informative profiling results.
4317 * Default MI syntax changed to "mi2".
4319 The default MI (machine interface) syntax, enabled by the command line
4320 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4321 "mi1", can be enabled by specifying the option "-i=mi1".
4323 Support for the original "mi0" syntax (included in GDB 5.0) has been
4326 Fix for gdb/192: removed extraneous space when displaying frame level.
4327 Fix for gdb/672: update changelist is now output in mi list format.
4328 Fix for gdb/702: a -var-assign that updates the value now shows up
4329 in a subsequent -var-update.
4331 * New native configurations.
4333 FreeBSD/amd64 x86_64-*-freebsd*
4335 * Multi-arched targets.
4337 HP/PA HPUX11 hppa*-*-hpux*
4338 Renesas M32R/D w/simulator m32r-*-elf*
4340 * OBSOLETE configurations and files
4342 Configurations that have been declared obsolete in this release have
4343 been commented out. Unless there is activity to revive these
4344 configurations, the next release of GDB will have their sources
4345 permanently REMOVED.
4347 Z8000 simulator z8k-zilog-none or z8ksim
4348 Matsushita MN10200 w/simulator mn10200-*-*
4349 H8/500 simulator h8500-hitachi-hms or h8500hms
4350 HP/PA running BSD hppa*-*-bsd*
4351 HP/PA running OSF/1 hppa*-*-osf*
4352 HP/PA Pro target hppa*-*-pro*
4353 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4354 Sequent family i[3456]86-sequent-sysv4*
4355 i[3456]86-sequent-sysv*
4356 i[3456]86-sequent-bsd*
4357 Tsqware Sparclet sparclet-*-*
4358 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4360 * REMOVED configurations and files
4363 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4364 IBM AIX PS/2 i[3456]86-*-aix
4365 i386 running Mach 3.0 i[3456]86-*-mach3*
4366 i386 running Mach i[3456]86-*-mach*
4367 i386 running OSF/1 i[3456]86-*osf1mk*
4368 HP/Apollo 68k Family m68*-apollo*-sysv*,
4370 m68*-hp-bsd*, m68*-hp-hpux*
4371 Argonaut Risc Chip (ARC) arc-*-*
4372 Mitsubishi D30V d30v-*-*
4373 Fujitsu FR30 fr30-*-elf*
4374 OS/9000 i[34]86-*-os9k
4375 I960 with MON960 i960-*-coff
4377 * MIPS $fp behavior changed
4379 The convenience variable $fp, for the MIPS, now consistently returns
4380 the address of the current frame's base. Previously, depending on the
4381 context, $fp could refer to either $sp or the current frame's base
4382 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4383 The GNU Source-Level Debugger''.
4385 *** Changes in GDB 5.3:
4387 * GNU/Linux shared library multi-threaded performance improved.
4389 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4390 `/proc', in preference to `ptrace' for memory reads. This may result
4391 in an improvement in the start-up time of multi-threaded, shared
4392 library applications when run under GDB. One GDB user writes: ``loads
4393 shared libs like mad''.
4395 * ``gdbserver'' now supports multi-threaded applications on some targets
4397 Support for debugging multi-threaded applications which use
4398 the GNU/Linux LinuxThreads package has been added for
4399 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4400 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4402 * GDB now supports C/C++ preprocessor macros.
4404 GDB now expands preprocessor macro invocations in C/C++ expressions,
4405 and provides various commands for showing macro definitions and how
4408 The new command `macro expand EXPRESSION' expands any macro
4409 invocations in expression, and shows the result.
4411 The new command `show macro MACRO-NAME' shows the definition of the
4412 macro named MACRO-NAME, and where it was defined.
4414 Most compilers don't include information about macros in the debugging
4415 information by default. In GCC 3.1, for example, you need to compile
4416 your program with the options `-gdwarf-2 -g3'. If the macro
4417 information is present in the executable, GDB will read it.
4419 * Multi-arched targets.
4421 DEC Alpha (partial) alpha*-*-*
4422 DEC VAX (partial) vax-*-*
4424 National Semiconductor NS32000 (partial) ns32k-*-*
4425 Motorola 68000 (partial) m68k-*-*
4426 Motorola MCORE mcore-*-*
4430 Fujitsu FRV architecture added by Red Hat frv*-*-*
4433 * New native configurations
4435 Alpha NetBSD alpha*-*-netbsd*
4436 SH NetBSD sh*-*-netbsdelf*
4437 MIPS NetBSD mips*-*-netbsd*
4438 UltraSPARC NetBSD sparc64-*-netbsd*
4440 * OBSOLETE configurations and files
4442 Configurations that have been declared obsolete in this release have
4443 been commented out. Unless there is activity to revive these
4444 configurations, the next release of GDB will have their sources
4445 permanently REMOVED.
4447 Mitsubishi D30V d30v-*-*
4448 OS/9000 i[34]86-*-os9k
4449 IBM AIX PS/2 i[3456]86-*-aix
4450 Fujitsu FR30 fr30-*-elf*
4451 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4452 Argonaut Risc Chip (ARC) arc-*-*
4453 i386 running Mach 3.0 i[3456]86-*-mach3*
4454 i386 running Mach i[3456]86-*-mach*
4455 i386 running OSF/1 i[3456]86-*osf1mk*
4456 HP/Apollo 68k Family m68*-apollo*-sysv*,
4458 m68*-hp-bsd*, m68*-hp-hpux*
4459 I960 with MON960 i960-*-coff
4461 * OBSOLETE languages
4463 CHILL, a Pascal like language used by telecommunications companies.
4465 * REMOVED configurations and files
4467 AMD 29k family via UDI a29k-amd-udi, udi29k
4468 A29K VxWorks a29k-*-vxworks
4469 AMD 29000 embedded, using EBMON a29k-none-none
4470 AMD 29000 embedded with COFF a29k-none-coff
4471 AMD 29000 embedded with a.out a29k-none-aout
4473 testsuite/gdb.hp/gdb.threads-hp/ directory
4475 * New command "set max-user-call-depth <nnn>"
4477 This command allows the user to limit the call depth of user-defined
4478 commands. The default is 1024.
4480 * Changes in FreeBSD/i386 native debugging.
4482 Support for the "generate-core-file" has been added.
4484 * New commands "dump", "append", and "restore".
4486 These commands allow data to be copied from target memory
4487 to a bfd-format or binary file (dump and append), and back
4488 from a file into memory (restore).
4490 * Improved "next/step" support on multi-processor Alpha Tru64.
4492 The previous single-step mechanism could cause unpredictable problems,
4493 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4494 of a software single-step mechanism prevents this.
4496 *** Changes in GDB 5.2.1:
4504 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4505 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4506 Fix, by Joel Brobecker imported from mainline.
4508 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4509 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4510 Fix, by Fred Fish, imported from mainline.
4512 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4513 Surprisingly enough, it works now.
4514 By Michal Ludvig, imported from mainline.
4516 i386 hardware watchpoint support:
4517 avoid misses on second run for some targets.
4518 By Pierre Muller, imported from mainline.
4520 *** Changes in GDB 5.2:
4522 * New command "set trust-readonly-sections on[off]".
4524 This command is a hint that tells gdb that read-only sections
4525 really are read-only (ie. that their contents will not change).
4526 In this mode, gdb will go to the object file rather than the
4527 target to read memory from read-only sections (such as ".text").
4528 This can be a significant performance improvement on some
4529 (notably embedded) targets.
4531 * New command "generate-core-file" (or "gcore").
4533 This new gdb command allows the user to drop a core file of the child
4534 process state at any time. So far it's been implemented only for
4535 GNU/Linux and Solaris, but should be relatively easily ported to other
4536 hosts. Argument is core file name (defaults to core.<pid>).
4538 * New command line option
4540 GDB now accepts --pid or -p followed by a process id.
4542 * Change in command line behavior -- corefiles vs. process ids.
4544 There is a subtle behavior in the way in which GDB handles
4545 command line arguments. The first non-flag argument is always
4546 a program to debug, but the second non-flag argument may either
4547 be a corefile or a process id. Previously, GDB would attempt to
4548 open the second argument as a corefile, and if that failed, would
4549 issue a superfluous error message and then attempt to attach it as
4550 a process. Now, if the second argument begins with a non-digit,
4551 it will be treated as a corefile. If it begins with a digit,
4552 GDB will attempt to attach it as a process, and if no such process
4553 is found, will then attempt to open it as a corefile.
4555 * Changes in ARM configurations.
4557 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4558 configuration is fully multi-arch.
4560 * New native configurations
4562 ARM NetBSD arm*-*-netbsd*
4563 x86 OpenBSD i[3456]86-*-openbsd*
4564 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4565 Sparc64 running FreeBSD sparc64-*-freebsd*
4569 Sanyo XStormy16 xstormy16-elf
4571 * OBSOLETE configurations and files
4573 Configurations that have been declared obsolete in this release have
4574 been commented out. Unless there is activity to revive these
4575 configurations, the next release of GDB will have their sources
4576 permanently REMOVED.
4578 AMD 29k family via UDI a29k-amd-udi, udi29k
4579 A29K VxWorks a29k-*-vxworks
4580 AMD 29000 embedded, using EBMON a29k-none-none
4581 AMD 29000 embedded with COFF a29k-none-coff
4582 AMD 29000 embedded with a.out a29k-none-aout
4584 testsuite/gdb.hp/gdb.threads-hp/ directory
4586 * REMOVED configurations and files
4588 TI TMS320C80 tic80-*-*
4590 PowerPC Solaris powerpcle-*-solaris*
4591 PowerPC Windows NT powerpcle-*-cygwin32
4592 PowerPC Netware powerpc-*-netware*
4593 Harris/CXUX m88k m88*-harris-cxux*
4594 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4595 ns32k-utek-sysv* ns32k-utek-*
4596 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4597 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4598 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4599 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4600 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4602 * Changes to command line processing
4604 The new `--args' feature can be used to specify command-line arguments
4605 for the inferior from gdb's command line.
4607 * Changes to key bindings
4609 There is a new `operate-and-get-next' function bound to `C-o'.
4611 *** Changes in GDB 5.1.1
4613 Fix compile problem on DJGPP.
4615 Fix a problem with floating-point registers on the i386 being
4618 Fix to stop GDB crashing on .debug_str debug info.
4620 Numerous documentation fixes.
4622 Numerous testsuite fixes.
4624 *** Changes in GDB 5.1:
4626 * New native configurations
4628 Alpha FreeBSD alpha*-*-freebsd*
4629 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4630 MIPS GNU/Linux mips*-*-linux*
4631 MIPS SGI Irix 6.x mips*-sgi-irix6*
4632 ia64 AIX ia64-*-aix*
4633 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4637 Motorola 68HC11 and 68HC12 m68hc11-elf
4639 UltraSparc running GNU/Linux sparc64-*-linux*
4641 * OBSOLETE configurations and files
4643 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4644 Harris/CXUX m88k m88*-harris-cxux*
4645 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4646 ns32k-utek-sysv* ns32k-utek-*
4647 TI TMS320C80 tic80-*-*
4649 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4650 PowerPC Solaris powerpcle-*-solaris*
4651 PowerPC Windows NT powerpcle-*-cygwin32
4652 PowerPC Netware powerpc-*-netware*
4653 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4654 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4655 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4656 Apple Macintosh (MPW) host N/A
4658 stuff.c (Program to stuff files into a specially prepared space in kdb)
4659 kdb-start.c (Main loop for the standalone kernel debugger)
4661 Configurations that have been declared obsolete in this release have
4662 been commented out. Unless there is activity to revive these
4663 configurations, the next release of GDB will have their sources
4664 permanently REMOVED.
4666 * REMOVED configurations and files
4668 Altos 3068 m68*-altos-*
4669 Convex c1-*-*, c2-*-*
4671 ARM RISCix arm-*-* (as host)
4675 * GDB has been converted to ISO C.
4677 GDB's source code has been converted to ISO C. In particular, the
4678 sources are fully protoized, and rely on standard headers being
4683 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4685 * The MI enabled by default.
4687 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4688 revised and enabled by default. Packages which use GDB as a debugging
4689 engine behind a UI or another front end are encouraged to switch to
4690 using the GDB/MI interface, instead of the old annotations interface
4691 which is now deprecated.
4693 * Support for debugging Pascal programs.
4695 GDB now includes support for debugging Pascal programs. The following
4696 main features are supported:
4698 - Pascal-specific data types such as sets;
4700 - automatic recognition of Pascal sources based on file-name
4703 - Pascal-style display of data types, variables, and functions;
4705 - a Pascal expression parser.
4707 However, some important features are not yet supported.
4709 - Pascal string operations are not supported at all;
4711 - there are some problems with boolean types;
4713 - Pascal type hexadecimal constants are not supported
4714 because they conflict with the internal variables format;
4716 - support for Pascal objects and classes is not full yet;
4718 - unlike Pascal, GDB is case-sensitive for symbol names.
4720 * Changes in completion.
4722 Commands such as `shell', `run' and `set args', which pass arguments
4723 to inferior programs, now complete on file names, similar to what
4724 users expect at the shell prompt.
4726 Commands which accept locations, such as `disassemble', `print',
4727 `breakpoint', `until', etc. now complete on filenames as well as
4728 program symbols. Thus, if you type "break foob TAB", and the source
4729 files linked into the programs include `foobar.c', that file name will
4730 be one of the candidates for completion. However, file names are not
4731 considered for completion after you typed a colon that delimits a file
4732 name from a name of a function in that file, as in "break foo.c:bar".
4734 `set demangle-style' completes on available demangling styles.
4736 * New platform-independent commands:
4738 It is now possible to define a post-hook for a command as well as a
4739 hook that runs before the command. For more details, see the
4740 documentation of `hookpost' in the GDB manual.
4742 * Changes in GNU/Linux native debugging.
4744 Support for debugging multi-threaded programs has been completely
4745 revised for all platforms except m68k and sparc. You can now debug as
4746 many threads as your system allows you to have.
4748 Attach/detach is supported for multi-threaded programs.
4750 Support for SSE registers was added for x86. This doesn't work for
4751 multi-threaded programs though.
4753 * Changes in MIPS configurations.
4755 Multi-arch support is enabled for all MIPS configurations.
4757 GDB can now be built as native debugger on SGI Irix 6.x systems for
4758 debugging n32 executables. (Debugging 64-bit executables is not yet
4761 * Unified support for hardware watchpoints in all x86 configurations.
4763 Most (if not all) native x86 configurations support hardware-assisted
4764 breakpoints and watchpoints in a unified manner. This support
4765 implements debug register sharing between watchpoints, which allows to
4766 put a virtually infinite number of watchpoints on the same address,
4767 and also supports watching regions up to 16 bytes with several debug
4770 The new maintenance command `maintenance show-debug-regs' toggles
4771 debugging print-outs in functions that insert, remove, and test
4772 watchpoints and hardware breakpoints.
4774 * Changes in the DJGPP native configuration.
4776 New command ``info dos sysinfo'' displays assorted information about
4777 the CPU, OS, memory, and DPMI server.
4779 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4780 display information about segment descriptors stored in GDT, LDT, and
4783 New commands ``info dos pde'' and ``info dos pte'' display entries
4784 from Page Directory and Page Tables (for now works with CWSDPMI only).
4785 New command ``info dos address-pte'' displays the Page Table entry for
4786 a given linear address.
4788 GDB can now pass command lines longer than 126 characters to the
4789 program being debugged (requires an update to the libdbg.a library
4790 which is part of the DJGPP development kit).
4792 DWARF2 debug info is now supported.
4794 It is now possible to `step' and `next' through calls to `longjmp'.
4796 * Changes in documentation.
4798 All GDB documentation was converted to GFDL, the GNU Free
4799 Documentation License.
4801 Tracepoints-related commands are now fully documented in the GDB
4804 TUI, the Text-mode User Interface, is now documented in the manual.
4806 Tracepoints-related commands are now fully documented in the GDB
4809 The "GDB Internals" manual now has an index. It also includes
4810 documentation of `ui_out' functions, GDB coding standards, x86
4811 hardware watchpoints, and memory region attributes.
4813 * GDB's version number moved to ``version.in''
4815 The Makefile variable VERSION has been replaced by the file
4816 ``version.in''. People creating GDB distributions should update the
4817 contents of this file.
4821 GUD support is now a standard part of the EMACS distribution.
4823 *** Changes in GDB 5.0:
4825 * Improved support for debugging FP programs on x86 targets
4827 Unified and much-improved support for debugging floating-point
4828 programs on all x86 targets. In particular, ``info float'' now
4829 displays the FP registers in the same format on all x86 targets, with
4830 greater level of detail.
4832 * Improvements and bugfixes in hardware-assisted watchpoints
4834 It is now possible to watch array elements, struct members, and
4835 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4836 on x86 targets no longer erroneously trigger when the address is
4839 * Improvements in the native DJGPP version of GDB
4841 The distribution now includes all the scripts and auxiliary files
4842 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4843 machines ``out of the box''.
4845 The DJGPP version can now debug programs that use signals. It is
4846 possible to catch signals that happened in the debuggee, deliver
4847 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4848 would kill the program being debugged.) Programs that hook hardware
4849 interrupts (keyboard, timer, etc.) can also be debugged.
4851 It is now possible to debug DJGPP programs that redirect their
4852 standard handles or switch them to raw (as opposed to cooked) mode, or
4853 even close them. The command ``run < foo > bar'' works as expected,
4854 and ``info terminal'' reports useful information about the debuggee's
4855 terminal, including raw/cooked mode, redirection, etc.
4857 The DJGPP version now uses termios functions for console I/O, which
4858 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4861 DOS-style file names with drive letters are now fully supported by
4864 It is now possible to debug DJGPP programs that switch their working
4865 directory. It is also possible to rerun the debuggee any number of
4866 times without restarting GDB; thus, you can use the same setup,
4867 breakpoints, etc. for many debugging sessions.
4869 * New native configurations
4871 ARM GNU/Linux arm*-*-linux*
4872 PowerPC GNU/Linux powerpc-*-linux*
4876 Motorola MCore mcore-*-*
4877 x86 VxWorks i[3456]86-*-vxworks*
4878 PowerPC VxWorks powerpc-*-vxworks*
4879 TI TMS320C80 tic80-*-*
4881 * OBSOLETE configurations
4883 Altos 3068 m68*-altos-*
4884 Convex c1-*-*, c2-*-*
4886 ARM RISCix arm-*-* (as host)
4889 Configurations that have been declared obsolete will be commented out,
4890 but the code will be left in place. If there is no activity to revive
4891 these configurations before the next release of GDB, the sources will
4892 be permanently REMOVED.
4894 * Gould support removed
4896 Support for the Gould PowerNode and NP1 has been removed.
4898 * New features for SVR4
4900 On SVR4 native platforms (such as Solaris), if you attach to a process
4901 without first loading a symbol file, GDB will now attempt to locate and
4902 load symbols from the running process's executable file.
4904 * Many C++ enhancements
4906 C++ support has been greatly improved. Overload resolution now works properly
4907 in almost all cases. RTTI support is on the way.
4909 * Remote targets can connect to a sub-program
4911 A popen(3) style serial-device has been added. This device starts a
4912 sub-process (such as a stand-alone simulator) and then communicates
4913 with that. The sub-program to run is specified using the syntax
4914 ``|<program> <args>'' vis:
4916 (gdb) set remotedebug 1
4917 (gdb) target extended-remote |mn10300-elf-sim program-args
4919 * MIPS 64 remote protocol
4921 A long standing bug in the mips64 remote protocol where by GDB
4922 expected certain 32 bit registers (ex SR) to be transfered as 32
4923 instead of 64 bits has been fixed.
4925 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4926 added to provide backward compatibility with older versions of GDB.
4928 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4930 The command ``set remotebinarydownload'' command has been replaced by
4931 ``set remote X-packet''. Other commands in ``set remote'' family
4932 include ``set remote P-packet''.
4934 * Breakpoint commands accept ranges.
4936 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4937 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4938 ``tracepoint passcount'' also accepts a range of tracepoints.
4940 * ``apropos'' command added.
4942 The ``apropos'' command searches through command names and
4943 documentation strings, printing out matches, making it much easier to
4944 try to find a command that does what you are looking for.
4948 A new machine oriented interface (MI) has been added to GDB. This
4949 interface is designed for debug environments running GDB as a separate
4950 process. This is part of the long term libGDB project. See the
4951 "GDB/MI" chapter of the GDB manual for further information. It can be
4952 enabled by configuring with:
4954 .../configure --enable-gdbmi
4956 *** Changes in GDB-4.18:
4958 * New native configurations
4960 HP-UX 10.20 hppa*-*-hpux10.20
4961 HP-UX 11.x hppa*-*-hpux11.0*
4962 M68K GNU/Linux m68*-*-linux*
4966 Fujitsu FR30 fr30-*-elf*
4967 Intel StrongARM strongarm-*-*
4968 Mitsubishi D30V d30v-*-*
4970 * OBSOLETE configurations
4972 Gould PowerNode, NP1 np1-*-*, pn-*-*
4974 Configurations that have been declared obsolete will be commented out,
4975 but the code will be left in place. If there is no activity to revive
4976 these configurations before the next release of GDB, the sources will
4977 be permanently REMOVED.
4981 As a compatibility experiment, GDB's source files buildsym.h and
4982 buildsym.c have been converted to pure standard C, no longer
4983 containing any K&R compatibility code. We believe that all systems in
4984 use today either come with a standard C compiler, or have a GCC port
4985 available. If this is not true, please report the affected
4986 configuration to bug-gdb@gnu.org immediately. See the README file for
4987 information about getting a standard C compiler if you don't have one
4992 GDB now uses readline 2.2.
4994 * set extension-language
4996 You can now control the mapping between filename extensions and source
4997 languages by using the `set extension-language' command. For instance,
4998 you can ask GDB to treat .c files as C++ by saying
4999 set extension-language .c c++
5000 The command `info extensions' lists all of the recognized extensions
5001 and their associated languages.
5003 * Setting processor type for PowerPC and RS/6000
5005 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5006 you can use the `set processor' command to specify what variant of the
5007 PowerPC family you are debugging. The command
5011 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5012 following PowerPC and RS6000 variants:
5014 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5015 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5017 403GC IBM PowerPC 403GC
5018 505 Motorola PowerPC 505
5019 860 Motorola PowerPC 860 or 850
5020 601 Motorola PowerPC 601
5021 602 Motorola PowerPC 602
5022 603 Motorola/IBM PowerPC 603 or 603e
5023 604 Motorola PowerPC 604 or 604e
5024 750 Motorola/IBM PowerPC 750 or 750
5026 At the moment, this command just tells GDB what to name the
5027 special-purpose processor registers. Since almost all the affected
5028 registers are inaccessible to user-level programs, this command is
5029 only useful for remote debugging in its present form.
5033 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5034 more extensive support for HP-UX. Added features include shared
5035 library support, kernel threads and hardware watchpoints for 11.00,
5036 support for HP's ANSI C and C++ compilers, and a compatibility mode
5037 for xdb and dbx commands.
5041 HP's donation includes the new concept of catchpoints, which is a
5042 generalization of the old catch command. On HP-UX, it is now possible
5043 to catch exec, fork, and vfork, as well as library loading.
5045 This means that the existing catch command has changed; its first
5046 argument now specifies the type of catch to be set up. See the
5047 output of "help catch" for a list of catchpoint types.
5049 * Debugging across forks
5051 On HP-UX, you can choose which process to debug when a fork() happens
5056 HP has donated a curses-based terminal user interface (TUI). To get
5057 it, build with --enable-tui. Although this can be enabled for any
5058 configuration, at present it only works for native HP debugging.
5060 * GDB remote protocol additions
5062 A new protocol packet 'X' that writes binary data is now available.
5063 Default behavior is to try 'X', then drop back to 'M' if the stub
5064 fails to respond. The settable variable `remotebinarydownload'
5065 allows explicit control over the use of 'X'.
5067 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5068 full 64-bit address. The command
5070 set remoteaddresssize 32
5072 can be used to revert to the old behaviour. For existing remote stubs
5073 the change should not be noticed, as the additional address information
5076 In order to assist in debugging stubs, you may use the maintenance
5077 command `packet' to send any text string to the stub. For instance,
5079 maint packet heythere
5081 sends the packet "$heythere#<checksum>". Note that it is very easy to
5082 disrupt a debugging session by sending the wrong packet at the wrong
5085 The compare-sections command allows you to compare section data on the
5086 target to what is in the executable file without uploading or
5087 downloading, by comparing CRC checksums.
5089 * Tracing can collect general expressions
5091 You may now collect general expressions at tracepoints. This requires
5092 further additions to the target-side stub; see tracepoint.c and
5093 doc/agentexpr.texi for further details.
5095 * mask-address variable for Mips
5097 For Mips targets, you may control the zeroing of the upper 32 bits of
5098 a 64-bit address by entering `set mask-address on'. This is mainly
5099 of interest to users of embedded R4xxx and R5xxx processors.
5101 * Higher serial baud rates
5103 GDB's serial code now allows you to specify baud rates 57600, 115200,
5104 230400, and 460800 baud. (Note that your host system may not be able
5105 to achieve all of these rates.)
5109 The i960 configuration now includes an initial implementation of a
5110 builtin simulator, contributed by Jim Wilson.
5113 *** Changes in GDB-4.17:
5115 * New native configurations
5117 Alpha GNU/Linux alpha*-*-linux*
5118 Unixware 2.x i[3456]86-unixware2*
5119 Irix 6.x mips*-sgi-irix6*
5120 PowerPC GNU/Linux powerpc-*-linux*
5121 PowerPC Solaris powerpcle-*-solaris*
5122 Sparc GNU/Linux sparc-*-linux*
5123 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5127 Argonaut Risc Chip (ARC) arc-*-*
5128 Hitachi H8/300S h8300*-*-*
5129 Matsushita MN10200 w/simulator mn10200-*-*
5130 Matsushita MN10300 w/simulator mn10300-*-*
5131 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5132 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5133 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5134 Mitsubishi D10V w/simulator d10v-*-*
5135 Mitsubishi M32R/D w/simulator m32r-*-elf*
5136 Tsqware Sparclet sparclet-*-*
5137 NEC V850 w/simulator v850-*-*
5139 * New debugging protocols
5141 ARM with RDI protocol arm*-*-*
5142 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5143 DDB and LSI variants of PMON protocol mips*-*-*
5144 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5145 PowerPC with SDS protocol powerpc{,le}-*-eabi
5146 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5150 All configurations can now understand and use the DWARF 2 debugging
5151 format. The choice is automatic, if the symbol file contains DWARF 2
5156 GDB now includes basic Java language support. This support is
5157 only useful with Java compilers that produce native machine code.
5159 * solib-absolute-prefix and solib-search-path
5161 For SunOS and SVR4 shared libraries, you may now set the prefix for
5162 loading absolute shared library symbol files, and the search path for
5163 locating non-absolute shared library symbol files.
5165 * Live range splitting
5167 GDB can now effectively debug code for which GCC has performed live
5168 range splitting as part of its optimization. See gdb/doc/LRS for
5169 more details on the expected format of the stabs information.
5173 GDB's support for the GNU Hurd, including thread debugging, has been
5174 updated to work with current versions of the Hurd.
5178 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5179 instruction set. ARM GDB automatically detects when Thumb
5180 instructions are in use, and adjusts disassembly and backtracing
5185 GDB's MIPS target configurations now handle the MIP16 16-bit
5190 GDB now includes support for overlays; if an executable has been
5191 linked such that multiple sections are based at the same address, GDB
5192 will decide which section to use for symbolic info. You can choose to
5193 control the decision manually, using overlay commands, or implement
5194 additional target-side support and use "overlay load-target" to bring
5195 in the overlay mapping. Do "help overlay" for more detail.
5199 The command "info symbol <address>" displays information about
5200 the symbol at the specified address.
5204 The standard remote protocol now includes an extension that allows
5205 asynchronous collection and display of trace data. This requires
5206 extensive support in the target-side debugging stub. Tracing mode
5207 includes a new interaction mode in GDB and new commands: see the
5208 file tracepoint.c for more details.
5212 Configurations for embedded MIPS now include a simulator contributed
5213 by Cygnus Solutions. The simulator supports the instruction sets
5214 of most MIPS variants.
5218 Sparc configurations may now include the ERC32 simulator contributed
5219 by the European Space Agency. The simulator is not built into
5220 Sparc targets by default; configure with --enable-sim to include it.
5224 For target configurations that may include multiple variants of a
5225 basic architecture (such as MIPS and SH), you may now set the
5226 architecture explicitly. "set arch" sets, "info arch" lists
5227 the possible architectures.
5229 *** Changes in GDB-4.16:
5231 * New native configurations
5233 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5234 M68K NetBSD m68k-*-netbsd*
5235 PowerPC AIX 4.x powerpc-*-aix*
5236 PowerPC MacOS powerpc-*-macos*
5237 PowerPC Windows NT powerpcle-*-cygwin32
5238 RS/6000 AIX 4.x rs6000-*-aix4*
5242 ARM with RDP protocol arm-*-*
5243 I960 with MON960 i960-*-coff
5244 MIPS VxWorks mips*-*-vxworks*
5245 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5246 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5248 Matra Sparclet sparclet-*-*
5252 The powerpc-eabi configuration now includes the PSIM simulator,
5253 contributed by Andrew Cagney, with assistance from Mike Meissner.
5254 PSIM is a very elaborate model of the PowerPC, including not only
5255 basic instruction set execution, but also details of execution unit
5256 performance and I/O hardware. See sim/ppc/README for more details.
5260 GDB now works with Solaris 2.5.
5262 * Windows 95/NT native
5264 GDB will now work as a native debugger on Windows 95 and Windows NT.
5265 To build it from source, you must use the "gnu-win32" environment,
5266 which uses a DLL to emulate enough of Unix to run the GNU tools.
5267 Further information, binaries, and sources are available at
5268 ftp.cygnus.com, under pub/gnu-win32.
5270 * dont-repeat command
5272 If a user-defined command includes the command `dont-repeat', then the
5273 command will not be repeated if the user just types return. This is
5274 useful if the command is time-consuming to run, so that accidental
5275 extra keystrokes don't run the same command many times.
5277 * Send break instead of ^C
5279 The standard remote protocol now includes an option to send a break
5280 rather than a ^C to the target in order to interrupt it. By default,
5281 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5283 * Remote protocol timeout
5285 The standard remote protocol includes a new variable `remotetimeout'
5286 that allows you to set the number of seconds before GDB gives up trying
5287 to read from the target. The default value is 2.
5289 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5291 By default GDB will automatically keep track of objects as they are
5292 loaded and unloaded by the dynamic linker. By using the command `set
5293 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5294 when shared library events occur, thus allowing you to set breakpoints
5295 in shared libraries which are explicitly loaded by the inferior.
5297 Note this feature does not work on hpux8. On hpux9 you must link
5298 /usr/lib/end.o into your program. This feature should work
5299 automatically on hpux10.
5301 * Irix 5.x hardware watchpoint support
5303 Irix 5 configurations now support the use of hardware watchpoints.
5305 * Mips protocol "SYN garbage limit"
5307 When debugging a Mips target using the `target mips' protocol, you
5308 may set the number of characters that GDB will ignore by setting
5309 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5310 every character. The default value is 1050.
5312 * Recording and replaying remote debug sessions
5314 If you set `remotelogfile' to the name of a file, gdb will write to it
5315 a recording of a remote debug session. This recording may then be
5316 replayed back to gdb using "gdbreplay". See gdbserver/README for
5317 details. This is useful when you have a problem with GDB while doing
5318 remote debugging; you can make a recording of the session and send it
5319 to someone else, who can then recreate the problem.
5321 * Speedups for remote debugging
5323 GDB includes speedups for downloading and stepping MIPS systems using
5324 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5325 and more efficient S-record downloading.
5327 * Memory use reductions and statistics collection
5329 GDB now uses less memory and reports statistics about memory usage.
5330 Try the `maint print statistics' command, for example.
5332 *** Changes in GDB-4.15:
5334 * Psymtabs for XCOFF
5336 The symbol reader for AIX GDB now uses partial symbol tables. This
5337 can greatly improve startup time, especially for large executables.
5339 * Remote targets use caching
5341 Remote targets now use a data cache to speed up communication with the
5342 remote side. The data cache could lead to incorrect results because
5343 it doesn't know about volatile variables, thus making it impossible to
5344 debug targets which use memory mapped I/O devices. `set remotecache
5345 off' turns the the data cache off.
5347 * Remote targets may have threads
5349 The standard remote protocol now includes support for multiple threads
5350 in the target system, using new protocol commands 'H' and 'T'. See
5351 gdb/remote.c for details.
5355 If GDB is configured with `--enable-netrom', then it will include
5356 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5357 acts as though it is a bank of ROM on the target board, but you can
5358 write into it over the network. GDB's support consists only of
5359 support for fast loading into the emulated ROM; to debug, you must use
5360 another protocol, such as standard remote protocol. The usual
5361 sequence is something like
5363 target nrom <netrom-hostname>
5365 target remote <netrom-hostname>:1235
5369 GDB now includes support for the Apple Macintosh, as a host only. It
5370 may be run as either an MPW tool or as a standalone application, and
5371 it can debug through the serial port. All the usual GDB commands are
5372 available, but to the target command, you must supply "serial" as the
5373 device type instead of "/dev/ttyXX". See mpw-README in the main
5374 directory for more information on how to build. The MPW configuration
5375 scripts */mpw-config.in support only a few targets, and only the
5376 mips-idt-ecoff target has been tested.
5380 GDB configuration now uses autoconf. This is not user-visible,
5381 but does simplify configuration and building.
5385 GDB now supports hpux10.
5387 *** Changes in GDB-4.14:
5389 * New native configurations
5391 x86 FreeBSD i[345]86-*-freebsd
5392 x86 NetBSD i[345]86-*-netbsd
5393 NS32k NetBSD ns32k-*-netbsd
5394 Sparc NetBSD sparc-*-netbsd
5398 A29K VxWorks a29k-*-vxworks
5399 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5400 CPU32 EST-300 emulator m68*-*-est*
5401 PowerPC ELF powerpc-*-elf
5404 * Alpha OSF/1 support for procfs
5406 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5407 possible to attach to running processes. As the mounting of the /proc
5408 filesystem is optional on the Alpha, GDB automatically determines
5409 the availability of /proc during startup. This can lead to problems
5410 if /proc is unmounted after GDB has been started.
5412 * Arguments to user-defined commands
5414 User commands may accept up to 10 arguments separated by whitespace.
5415 Arguments are accessed within the user command via $arg0..$arg9. A
5418 print $arg0 + $arg1 + $arg2
5420 To execute the command use:
5423 Defines the command "adder" which prints the sum of its three arguments.
5424 Note the arguments are text substitutions, so they may reference variables,
5425 use complex expressions, or even perform inferior function calls.
5427 * New `if' and `while' commands
5429 This makes it possible to write more sophisticated user-defined
5430 commands. Both commands take a single argument, which is the
5431 expression to evaluate, and must be followed by the commands to
5432 execute, one per line, if the expression is nonzero, the list being
5433 terminated by the word `end'. The `if' command list may include an
5434 `else' word, which causes the following commands to be executed only
5435 if the expression is zero.
5437 * Fortran source language mode
5439 GDB now includes partial support for Fortran 77. It will recognize
5440 Fortran programs and can evaluate a subset of Fortran expressions, but
5441 variables and functions may not be handled correctly. GDB will work
5442 with G77, but does not yet know much about symbols emitted by other
5445 * Better HPUX support
5447 Most debugging facilities now work on dynamic executables for HPPAs
5448 running hpux9 or later. You can attach to running dynamically linked
5449 processes, but by default the dynamic libraries will be read-only, so
5450 for instance you won't be able to put breakpoints in them. To change
5451 that behavior do the following before running the program:
5457 This will cause the libraries to be mapped private and read-write.
5458 To revert to the normal behavior, do this:
5464 You cannot set breakpoints or examine data in the library until after
5465 the library is loaded if the function/data symbols do not have
5468 GDB can now also read debug symbols produced by the HP C compiler on
5469 HPPAs (sorry, no C++, Fortran or 68k support).
5471 * Target byte order now dynamically selectable
5473 You can choose which byte order to use with a target system, via the
5474 commands "set endian big" and "set endian little", and you can see the
5475 current setting by using "show endian". You can also give the command
5476 "set endian auto", in which case GDB will use the byte order
5477 associated with the executable. Currently, only embedded MIPS
5478 configurations support dynamic selection of target byte order.
5480 * New DOS host serial code
5482 This version uses DPMI interrupts to handle buffered I/O, so you
5483 no longer need to run asynctsr when debugging boards connected to
5486 *** Changes in GDB-4.13:
5488 * New "complete" command
5490 This lists all the possible completions for the rest of the line, if it
5491 were to be given as a command itself. This is intended for use by emacs.
5493 * Trailing space optional in prompt
5495 "set prompt" no longer adds a space for you after the prompt you set. This
5496 allows you to set a prompt which ends in a space or one that does not.
5498 * Breakpoint hit counts
5500 "info break" now displays a count of the number of times the breakpoint
5501 has been hit. This is especially useful in conjunction with "ignore"; you
5502 can ignore a large number of breakpoint hits, look at the breakpoint info
5503 to see how many times the breakpoint was hit, then run again, ignoring one
5504 less than that number, and this will get you quickly to the last hit of
5507 * Ability to stop printing at NULL character
5509 "set print null-stop" will cause GDB to stop printing the characters of
5510 an array when the first NULL is encountered. This is useful when large
5511 arrays actually contain only short strings.
5513 * Shared library breakpoints
5515 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5516 breakpoints in shared libraries before the executable is run.
5518 * Hardware watchpoints
5520 There is a new hardware breakpoint for the watch command for sparclite
5521 targets. See gdb/sparclite/hw_breakpoint.note.
5523 Hardware watchpoints are also now supported under GNU/Linux.
5527 Annotations have been added. These are for use with graphical interfaces,
5528 and are still experimental. Currently only gdba.el uses these.
5530 * Improved Irix 5 support
5532 GDB now works properly with Irix 5.2.
5534 * Improved HPPA support
5536 GDB now works properly with the latest GCC and GAS.
5538 * New native configurations
5540 Sequent PTX4 i[34]86-sequent-ptx4
5541 HPPA running OSF/1 hppa*-*-osf*
5542 Atari TT running SVR4 m68*-*-sysv4*
5543 RS/6000 LynxOS rs6000-*-lynxos*
5547 OS/9000 i[34]86-*-os9k
5548 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5551 * Hitachi SH7000 and E7000-PC ICE support
5553 There is now support for communicating with the Hitachi E7000-PC ICE.
5554 This is available automatically when GDB is configured for the SH.
5558 As usual, a variety of small fixes and improvements, both generic
5559 and configuration-specific. See the ChangeLog for more detail.
5561 *** Changes in GDB-4.12:
5563 * Irix 5 is now supported
5567 GDB-4.12 on the HPPA has a number of changes which make it unable
5568 to debug the output from the currently released versions of GCC and
5569 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5570 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5571 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5574 *** Changes in GDB-4.11:
5576 * User visible changes:
5580 The "set remotedebug" option is now consistent between the mips remote
5581 target, remote targets using the gdb-specific protocol, UDI (AMD's
5582 debug protocol for the 29k) and the 88k bug monitor. It is now an
5583 integer specifying a debug level (normally 0 or 1, but 2 means more
5584 debugging info for the mips target).
5586 * DEC Alpha native support
5588 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5589 debug info, but GDB works fairly well with the DEC compiler and should
5590 work with a future GCC release. See the README file for a few
5591 Alpha-specific notes.
5593 * Preliminary thread implementation
5595 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5597 * LynxOS native and target support for 386
5599 This release has been hosted on LynxOS 2.2, and also can be configured
5600 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5603 * Improvements in C++ mangling/demangling.
5605 This release has much better g++ debugging, specifically in name
5606 mangling/demangling, virtual function calls, print virtual table,
5607 call methods, ...etc.
5609 *** Changes in GDB-4.10:
5611 * User visible changes:
5613 Remote debugging using the GDB-specific (`target remote') protocol now
5614 supports the `load' command. This is only useful if you have some
5615 other way of getting the stub to the target system, and you can put it
5616 somewhere in memory where it won't get clobbered by the download.
5618 Filename completion now works.
5620 When run under emacs mode, the "info line" command now causes the
5621 arrow to point to the line specified. Also, "info line" prints
5622 addresses in symbolic form (as well as hex).
5624 All vxworks based targets now support a user settable option, called
5625 vxworks-timeout. This option represents the number of seconds gdb
5626 should wait for responses to rpc's. You might want to use this if
5627 your vxworks target is, perhaps, a slow software simulator or happens
5628 to be on the far side of a thin network line.
5632 This release contains support for using a DEC alpha as a GDB host for
5633 cross debugging. Native alpha debugging is not supported yet.
5636 *** Changes in GDB-4.9:
5640 This is the first GDB release which is accompanied by a matching testsuite.
5641 The testsuite requires installation of dejagnu, which should be available
5642 via ftp from most sites that carry GNU software.
5646 'Cfront' style demangling has had its name changed to 'ARM' style, to
5647 emphasize that it was written from the specifications in the C++ Annotated
5648 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5649 disclaimers, it still generated too much confusion with users attempting to
5650 use gdb with AT&T cfront.
5654 GDB now uses a standard remote interface to a simulator library.
5655 So far, the library contains simulators for the Zilog Z8001/2, the
5656 Hitachi H8/300, H8/500 and Super-H.
5658 * New targets supported
5660 H8/300 simulator h8300-hitachi-hms or h8300hms
5661 H8/500 simulator h8500-hitachi-hms or h8500hms
5662 SH simulator sh-hitachi-hms or sh
5663 Z8000 simulator z8k-zilog-none or z8ksim
5664 IDT MIPS board over serial line mips-idt-ecoff
5666 Cross-debugging to GO32 targets is supported. It requires a custom
5667 version of the i386-stub.c module which is integrated with the
5668 GO32 memory extender.
5670 * New remote protocols
5672 MIPS remote debugging protocol.
5674 * New source languages supported
5676 This version includes preliminary support for Chill, a Pascal like language
5677 used by telecommunications companies. Chill support is also being integrated
5678 into the GNU compiler, but we don't know when it will be publically available.
5681 *** Changes in GDB-4.8:
5683 * HP Precision Architecture supported
5685 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5686 version of this support was available as a set of patches from the
5687 University of Utah. GDB does not support debugging of programs
5688 compiled with the HP compiler, because HP will not document their file
5689 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5690 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5692 Many problems in the preliminary version have been fixed.
5694 * Faster and better demangling
5696 We have improved template demangling and fixed numerous bugs in the GNU style
5697 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5698 character types (wchar_t) are now supported. Demangling of each symbol is now
5699 only done once, and is cached when the symbol table for a file is read in.
5700 This results in a small increase in memory usage for C programs, a moderate
5701 increase in memory usage for C++ programs, and a fantastic speedup in
5704 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5705 from the specifications in the Annotated Reference Manual, which AT&T's
5706 compiler does not actually implement.
5708 * G++ multiple inheritance compiler problem
5710 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5711 inheritance lattices was reworked to properly discover ambiguities. We
5712 recently found an example which causes this new algorithm to fail in a
5713 very subtle way, producing bad debug information for those classes.
5714 The file 'gcc.patch' (in this directory) can be applied to gcc to
5715 circumvent the problem. A future GCC release will contain a complete
5718 The previous G++ debug info problem (mentioned below for the gdb-4.7
5719 release) is fixed in gcc version 2.3.2.
5721 * Improved configure script
5723 The `configure' script will now attempt to guess your system type if
5724 you don't supply a host system type. The old scheme of supplying a
5725 host system triplet is preferable over using this. All the magic is
5726 done in the new `config.guess' script. Examine it for details.
5728 We have also brought our configure script much more in line with the FSF's
5729 version. It now supports the --with-xxx options. In particular,
5730 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5731 The resulting GDB will not be able to read arbitrary object file formats --
5732 only the format ``expected'' to be used on the configured target system.
5733 We hope to make this the default in a future release.
5735 * Documentation improvements
5737 There's new internal documentation on how to modify GDB, and how to
5738 produce clean changes to the code. We implore people to read it
5739 before submitting changes.
5741 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5742 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5743 `info' files are also provided. To build `info' files from scratch,
5744 you will need the latest `makeinfo' release, which will be available in
5745 a future texinfo-X.Y release.
5747 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5748 We're not sure exactly which versions have this problem, but it has
5749 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5750 or better. If that isn't possible, there is a patch in
5751 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5752 around this problem.
5756 GDB now supports array constants that can be used in expressions typed in by
5757 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5758 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5761 The new directory `gdb/sparclite' contains a program that demonstrates
5762 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5764 * New native hosts supported
5766 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5767 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5769 * New targets supported
5771 AMD 29k family via UDI a29k-amd-udi or udi29k
5773 * New file formats supported
5775 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5776 HPUX core files, and SCO 3.2v2 core files.
5780 Attaching to processes now works again; thanks for the many bug reports.
5782 We have also stomped on a bunch of core dumps caused by
5783 printf_filtered("%s") problems.
5785 We eliminated a copyright problem on the rpc and ptrace header files
5786 for VxWorks, which was discovered at the last minute during the 4.7
5787 release. You should now be able to build a VxWorks GDB.
5789 You can now interrupt gdb while an attached process is running. This
5790 will cause the attached process to stop, and give control back to GDB.
5792 We fixed problems caused by using too many file descriptors
5793 for reading symbols from object files and libraries. This was
5794 especially a problem for programs that used many (~100) shared
5797 The `step' command now only enters a subroutine if there is line number
5798 information for the subroutine. Otherwise it acts like the `next'
5799 command. Previously, `step' would enter subroutines if there was
5800 any debugging information about the routine. This avoids problems
5801 when using `cc -g1' on MIPS machines.
5803 * Internal improvements
5805 GDB's internal interfaces have been improved to make it easier to support
5806 debugging of multiple languages in the future.
5808 GDB now uses a common structure for symbol information internally.
5809 Minimal symbols (derived from linkage symbols in object files), partial
5810 symbols (from a quick scan of debug information), and full symbols
5811 contain a common subset of information, making it easier to write
5812 shared code that handles any of them.
5814 * New command line options
5816 We now accept --silent as an alias for --quiet.
5820 The memory-mapped-malloc library is now licensed under the GNU Library
5821 General Public License.
5823 *** Changes in GDB-4.7:
5825 * Host/native/target split
5827 GDB has had some major internal surgery to untangle the support for
5828 hosts and remote targets. Now, when you configure GDB for a remote
5829 target, it will no longer load in all of the support for debugging
5830 local programs on the host. When fully completed and tested, this will
5831 ensure that arbitrary host/target combinations are possible.
5833 The primary conceptual shift is to separate the non-portable code in
5834 GDB into three categories. Host specific code is required any time GDB
5835 is compiled on that host, regardless of the target. Target specific
5836 code relates to the peculiarities of the target, but can be compiled on
5837 any host. Native specific code is everything else: it can only be
5838 built when the host and target are the same system. Child process
5839 handling and core file support are two common `native' examples.
5841 GDB's use of /proc for controlling Unix child processes is now cleaner.
5842 It has been split out into a single module under the `target_ops' vector,
5843 plus two native-dependent functions for each system that uses /proc.
5845 * New hosts supported
5847 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5848 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5849 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5851 * New targets supported
5853 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5854 68030 and CPU32 m68030-*-*, m68332-*-*
5856 * New native hosts supported
5858 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5859 (386bsd is not well tested yet)
5860 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5862 * New file formats supported
5864 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5865 supports reading of `a.out.adobe' object files, which are an a.out
5866 format extended with minimal information about multiple sections.
5870 `show copying' is the same as the old `info copying'.
5871 `show warranty' is the same as `info warrantee'.
5872 These were renamed for consistency. The old commands continue to work.
5874 `info handle' is a new alias for `info signals'.
5876 You can now define pre-command hooks, which attach arbitrary command
5877 scripts to any command. The commands in the hook will be executed
5878 prior to the user's command. You can also create a hook which will be
5879 executed whenever the program stops. See gdb.texinfo.
5883 We now deal with Cfront style name mangling, and can even extract type
5884 info from mangled symbols. GDB can automatically figure out which
5885 symbol mangling style your C++ compiler uses.
5887 Calling of methods and virtual functions has been improved as well.
5891 The crash that occured when debugging Sun Ansi-C compiled binaries is
5892 fixed. This was due to mishandling of the extra N_SO stabs output
5895 We also finally got Ultrix 4.2 running in house, and fixed core file
5896 support, with help from a dozen people on the net.
5898 John M. Farrell discovered that the reason that single-stepping was so
5899 slow on all of the Mips based platforms (primarily SGI and DEC) was
5900 that we were trying to demangle and lookup a symbol used for internal
5901 purposes on every instruction that was being stepped through. Changing
5902 the name of that symbol so that it couldn't be mistaken for a C++
5903 mangled symbol sped things up a great deal.
5905 Rich Pixley sped up symbol lookups in general by getting much smarter
5906 about when C++ symbol mangling is necessary. This should make symbol
5907 completion (TAB on the command line) much faster. It's not as fast as
5908 we'd like, but it's significantly faster than gdb-4.6.
5912 A new user controllable variable 'call_scratch_address' can
5913 specify the location of a scratch area to be used when GDB
5914 calls a function in the target. This is necessary because the
5915 usual method of putting the scratch area on the stack does not work
5916 in systems that have separate instruction and data spaces.
5918 We integrated changes to support the 29k UDI (Universal Debugger
5919 Interface), but discovered at the last minute that we didn't have all
5920 of the appropriate copyright paperwork. We are working with AMD to
5921 resolve this, and hope to have it available soon.
5925 We have sped up the remote serial line protocol, especially for targets
5926 with lots of registers. It now supports a new `expedited status' ('T')
5927 message which can be used in place of the existing 'S' status message.
5928 This allows the remote stub to send only the registers that GDB
5929 needs to make a quick decision about single-stepping or conditional
5930 breakpoints, eliminating the need to fetch the entire register set for
5931 each instruction being stepped through.
5933 The GDB remote serial protocol now implements a write-through cache for
5934 registers, only re-reading the registers if the target has run.
5936 There is also a new remote serial stub for SPARC processors. You can
5937 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5938 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5939 processor with a serial port.
5943 Configure.in files have become much easier to read and modify. A new
5944 `table driven' format makes it more obvious what configurations are
5945 supported, and what files each one uses.
5949 There is a new opcodes library which will eventually contain all of the
5950 disassembly routines and opcode tables. At present, it only contains
5951 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5952 disassembler (binutils/objdump) to share these routines.
5954 The libiberty library is now copylefted under the GNU Library General
5955 Public License. This allows more liberal use, and was done so libg++
5956 can use it. This makes no difference to GDB, since the Library License
5957 grants all the rights from the General Public License.
5961 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5962 reference to the stabs symbol info used by the debugger. It is (as far
5963 as we know) the only published document on this fascinating topic. We
5964 encourage you to read it, compare it to the stabs information on your
5965 system, and send improvements on the document in general (to
5966 bug-gdb@prep.ai.mit.edu).
5968 And, of course, many bugs have been fixed.
5971 *** Changes in GDB-4.6:
5973 * Better support for C++ function names
5975 GDB now accepts as input the "demangled form" of C++ overloaded function
5976 names and member function names, and can do command completion on such names
5977 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5978 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5979 Make use of command completion, it is your friend.
5981 GDB also now accepts a variety of C++ mangled symbol formats. They are
5982 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5983 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5984 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5985 for the list of formats.
5987 * G++ symbol mangling problem
5989 Recent versions of gcc have a bug in how they emit debugging information for
5990 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5991 directory) can be applied to gcc to fix the problem. Alternatively, if you
5992 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5993 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5994 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5997 * New 'maintenance' command
5999 All of the commands related to hacking GDB internals have been moved out of
6000 the main command set, and now live behind the 'maintenance' command. This
6001 can also be abbreviated as 'mt'. The following changes were made:
6003 dump-me -> maintenance dump-me
6004 info all-breakpoints -> maintenance info breakpoints
6005 printmsyms -> maintenance print msyms
6006 printobjfiles -> maintenance print objfiles
6007 printpsyms -> maintenance print psymbols
6008 printsyms -> maintenance print symbols
6010 The following commands are new:
6012 maintenance demangle Call internal GDB demangler routine to
6013 demangle a C++ link name and prints the result.
6014 maintenance print type Print a type chain for a given symbol
6016 * Change to .gdbinit file processing
6018 We now read the $HOME/.gdbinit file before processing the argv arguments
6019 (e.g. reading symbol files or core files). This allows global parameters to
6020 be set, which will apply during the symbol reading. The ./.gdbinit is still
6021 read after argv processing.
6023 * New hosts supported
6025 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6027 GNU/Linux support i386-unknown-linux or linux
6029 We are also including code to support the HP/PA running BSD and HPUX. This
6030 is almost guaranteed not to work, as we didn't have time to test or build it
6031 for this release. We are including it so that the more adventurous (or
6032 masochistic) of you can play with it. We also had major problems with the
6033 fact that the compiler that we got from HP doesn't support the -g option.
6036 * New targets supported
6038 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6040 * More smarts about finding #include files
6042 GDB now remembers the compilation directory for all include files, and for
6043 all files from which C is generated (like yacc and lex sources). This
6044 greatly improves GDB's ability to find yacc/lex sources, and include files,
6045 especially if you are debugging your program from a directory different from
6046 the one that contains your sources.
6048 We also fixed a bug which caused difficulty with listing and setting
6049 breakpoints in include files which contain C code. (In the past, you had to
6050 try twice in order to list an include file that you hadn't looked at before.)
6052 * Interesting infernals change
6054 GDB now deals with arbitrary numbers of sections, where the symbols for each
6055 section must be relocated relative to that section's landing place in the
6056 target's address space. This work was needed to support ELF with embedded
6057 stabs used by Solaris-2.0.
6059 * Bug fixes (of course!)
6061 There have been loads of fixes for the following things:
6062 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6063 i960, stabs, DOS(GO32), procfs, etc...
6065 See the ChangeLog for details.
6067 *** Changes in GDB-4.5:
6069 * New machines supported (host and target)
6071 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6073 SGI Irix-4.x mips-sgi-irix4 or iris4
6075 * New malloc package
6077 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6078 Mmalloc is capable of handling mutiple heaps of memory. It is also
6079 capable of saving a heap to a file, and then mapping it back in later.
6080 This can be used to greatly speedup the startup of GDB by using a
6081 pre-parsed symbol table which lives in a mmalloc managed heap. For
6082 more details, please read mmalloc/mmalloc.texi.
6086 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6087 'help info proc' for details.
6089 * MIPS ecoff symbol table format
6091 The code that reads MIPS symbol table format is now supported on all hosts.
6092 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6095 * File name changes for MS-DOS
6097 Many files in the config directories have been renamed to make it easier to
6098 support GDB on MS-DOSe systems (which have very restrictive file name
6099 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6100 environment) is close to working but has some remaining problems. Note
6101 that debugging of DOS programs is not supported, due to limitations
6102 in the ``operating system'', but it can be used to host cross-debugging.
6104 * Cross byte order fixes
6106 Many fixes have been made to support cross debugging of Sparc and MIPS
6107 targets from hosts whose byte order differs.
6109 * New -mapped and -readnow options
6111 If memory-mapped files are available on your system through the 'mmap'
6112 system call, you can use the -mapped option on the `file' or
6113 `symbol-file' commands to cause GDB to write the symbols from your
6114 program into a reusable file. If the program you are debugging is
6115 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6116 Future GDB debugging sessions will notice the presence of this file,
6117 and will quickly map in symbol information from it, rather than reading
6118 the symbol table from the executable program. Using the '-mapped'
6119 option in a GDB `file' or `symbol-file' command has the same effect as
6120 starting GDB with the '-mapped' command-line option.
6122 You can cause GDB to read the entire symbol table immediately by using
6123 the '-readnow' option with any of the commands that load symbol table
6124 information (or on the GDB command line). This makes the command
6125 slower, but makes future operations faster.
6127 The -mapped and -readnow options are typically combined in order to
6128 build a `fred.syms' file that contains complete symbol information.
6129 A simple GDB invocation to do nothing but build a `.syms' file for future
6132 gdb -batch -nx -mapped -readnow programname
6134 The `.syms' file is specific to the host machine on which GDB is run.
6135 It holds an exact image of GDB's internal symbol table. It cannot be
6136 shared across multiple host platforms.
6138 * longjmp() handling
6140 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6141 siglongjmp() without losing control. This feature has not yet been ported to
6142 all systems. It currently works on many 386 platforms, all MIPS-based
6143 platforms (SGI, DECstation, etc), and Sun3/4.
6147 Preliminary work has been put in to support the new Solaris OS from Sun. At
6148 this time, it can control and debug processes, but it is not capable of
6153 As always, many many bug fixes. The major areas were with g++, and mipsread.
6154 People using the MIPS-based platforms should experience fewer mysterious
6155 crashes and trashed symbol tables.
6157 *** Changes in GDB-4.4:
6159 * New machines supported (host and target)
6161 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6163 BSD Reno on Vax vax-dec-bsd
6164 Ultrix on Vax vax-dec-ultrix
6166 * New machines supported (target)
6168 AMD 29000 embedded, using EBMON a29k-none-none
6172 GDB continues to improve its handling of C++. `References' work better.
6173 The demangler has also been improved, and now deals with symbols mangled as
6174 per the Annotated C++ Reference Guide.
6176 GDB also now handles `stabs' symbol information embedded in MIPS
6177 `ecoff' symbol tables. Since the ecoff format was not easily
6178 extensible to handle new languages such as C++, this appeared to be a
6179 good way to put C++ debugging info into MIPS binaries. This option
6180 will be supported in the GNU C compiler, version 2, when it is
6183 * New features for SVR4
6185 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6186 shared libraries. Debugging dynamically linked programs should present
6187 only minor differences from debugging statically linked programs.
6189 The `info proc' command will print out information about any process
6190 on an SVR4 system (including the one you are debugging). At the moment,
6191 it prints the address mappings of the process.
6193 If you bring up GDB on another SVR4 system, please send mail to
6194 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6196 * Better dynamic linking support in SunOS
6198 Reading symbols from shared libraries which contain debugging symbols
6199 now works properly. However, there remain issues such as automatic
6200 skipping of `transfer vector' code during function calls, which
6201 make it harder to debug code in a shared library, than to debug the
6202 same code linked statically.
6206 GDB is now using the latest `getopt' routines from the FSF. This
6207 version accepts the -- prefix for options with long names. GDB will
6208 continue to accept the old forms (-option and +option) as well.
6209 Various single letter abbreviations for options have been explicity
6210 added to the option table so that they won't get overshadowed in the
6211 future by other options that begin with the same letter.
6215 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6216 Many assorted bugs have been handled. Many more remain to be handled.
6217 See the various ChangeLog files (primarily in gdb and bfd) for details.
6220 *** Changes in GDB-4.3:
6222 * New machines supported (host and target)
6224 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6225 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6226 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6228 * Almost SCO Unix support
6230 We had hoped to support:
6231 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6232 (except for core file support), but we discovered very late in the release
6233 that it has problems with process groups that render gdb unusable. Sorry
6234 about that. I encourage people to fix it and post the fixes.
6236 * Preliminary ELF and DWARF support
6238 GDB can read ELF object files on System V Release 4, and can handle
6239 debugging records for C, in DWARF format, in ELF files. This support
6240 is preliminary. If you bring up GDB on another SVR4 system, please
6241 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6246 GDB now uses the latest `readline' library. One user-visible change
6247 is that two tabs will list possible command completions, which previously
6248 required typing M-? (meta-question mark, or ESC ?).
6252 The `stepi' bug that many of you noticed has been squashed.
6253 Many bugs in C++ have been handled. Many more remain to be handled.
6254 See the various ChangeLog files (primarily in gdb and bfd) for details.
6256 * State of the MIPS world (in case you wondered):
6258 GDB can understand the symbol tables emitted by the compilers
6259 supplied by most vendors of MIPS-based machines, including DEC. These
6260 symbol tables are in a format that essentially nobody else uses.
6262 Some versions of gcc come with an assembler post-processor called
6263 mips-tfile. This program is required if you want to do source-level
6264 debugging of gcc-compiled programs. I believe FSF does not ship
6265 mips-tfile with gcc version 1, but it will eventually come with gcc
6268 Debugging of g++ output remains a problem. g++ version 1.xx does not
6269 really support it at all. (If you're lucky, you should be able to get
6270 line numbers and stack traces to work, but no parameters or local
6271 variables.) With some work it should be possible to improve the
6274 When gcc version 2 is released, you will have somewhat better luck.
6275 However, even then you will get confusing results for inheritance and
6278 We will eventually provide full debugging of g++ output on
6279 DECstations. This will probably involve some kind of stabs-in-ecoff
6280 encapulation, but the details have not been worked out yet.
6283 *** Changes in GDB-4.2:
6285 * Improved configuration
6287 Only one copy of `configure' exists now, and it is not self-modifying.
6288 Porting BFD is simpler.
6292 The `step' and `next' commands now only stop at the first instruction
6293 of a source line. This prevents the multiple stops that used to occur
6294 in switch statements, for-loops, etc. `Step' continues to stop if a
6295 function that has debugging information is called within the line.
6299 Lots of small bugs fixed. More remain.
6301 * New host supported (not target)
6303 Intel 386 PC clone running Mach i386-none-mach
6306 *** Changes in GDB-4.1:
6308 * Multiple source language support
6310 GDB now has internal scaffolding to handle several source languages.
6311 It determines the type of each source file from its filename extension,
6312 and will switch expression parsing and number formatting to match the
6313 language of the function in the currently selected stack frame.
6314 You can also specifically set the language to be used, with
6315 `set language c' or `set language modula-2'.
6319 GDB now has preliminary support for the GNU Modula-2 compiler,
6320 currently under development at the State University of New York at
6321 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6322 continue through the fall of 1991 and into 1992.
6324 Other Modula-2 compilers are currently not supported, and attempting to
6325 debug programs compiled with them will likely result in an error as the
6326 symbol table is read. Feel free to work on it, though!
6328 There are hooks in GDB for strict type checking and range checking,
6329 in the `Modula-2 philosophy', but they do not currently work.
6333 GDB can now write to executable and core files (e.g. patch
6334 a variable's value). You must turn this switch on, specify
6335 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6336 by assigning a new value to a variable. Modifications take
6339 * Automatic SunOS shared library reading
6341 When you run your program, GDB automatically determines where its
6342 shared libraries (if any) have been loaded, and reads their symbols.
6343 The `share' command is no longer needed. This also works when
6344 examining core files.
6348 You can specify the number of lines that the `list' command shows.
6351 * New machines supported (host and target)
6353 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6354 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6355 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6357 * New hosts supported (not targets)
6359 IBM RT/PC: romp-ibm-aix or rtpc
6361 * New targets supported (not hosts)
6363 AMD 29000 embedded with COFF a29k-none-coff
6364 AMD 29000 embedded with a.out a29k-none-aout
6365 Ultracomputer remote kernel debug a29k-nyu-kern
6367 * New remote interfaces
6373 *** Changes in GDB-4.0:
6377 Wide output is wrapped at good places to make the output more readable.
6379 Gdb now supports cross-debugging from a host machine of one type to a
6380 target machine of another type. Communication with the target system
6381 is over serial lines. The ``target'' command handles connecting to the
6382 remote system; the ``load'' command will download a program into the
6383 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6384 also supports debugging of realtime processes running under VxWorks,
6385 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6386 stub on the target system.
6388 New CPUs supported include the AMD 29000 and Intel 960.
6390 GDB now reads object files and symbol tables via a ``binary file''
6391 library, which allows a single copy of GDB to debug programs of multiple
6392 object file types such as a.out and coff.
6394 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6395 refcard.dvi and refcard.ps are available to format it).
6398 * Control-Variable user interface simplified
6400 All variables that control the operation of the debugger can be set
6401 by the ``set'' command, and displayed by the ``show'' command.
6403 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6404 ``Show prompt'' produces the response:
6405 Gdb's prompt is new-gdb=>.
6407 What follows are the NEW set commands. The command ``help set'' will
6408 print a complete list of old and new set commands. ``help set FOO''
6409 will give a longer description of the variable FOO. ``show'' will show
6410 all of the variable descriptions and their current settings.
6412 confirm on/off: Enables warning questions for operations that are
6413 hard to recover from, e.g. rerunning the program while
6414 it is already running. Default is ON.
6416 editing on/off: Enables EMACS style command line editing
6417 of input. Previous lines can be recalled with
6418 control-P, the current line can be edited with control-B,
6419 you can search for commands with control-R, etc.
6422 history filename NAME: NAME is where the gdb command history
6423 will be stored. The default is .gdb_history,
6424 or the value of the environment variable
6427 history size N: The size, in commands, of the command history. The
6428 default is 256, or the value of the environment variable
6431 history save on/off: If this value is set to ON, the history file will
6432 be saved after exiting gdb. If set to OFF, the
6433 file will not be saved. The default is OFF.
6435 history expansion on/off: If this value is set to ON, then csh-like
6436 history expansion will be performed on
6437 command line input. The default is OFF.
6439 radix N: Sets the default radix for input and output. It can be set
6440 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6441 in the current radix, so "set radix 10" is always a no-op.
6443 height N: This integer value is the number of lines on a page. Default
6444 is 24, the current `stty rows'' setting, or the ``li#''
6445 setting from the termcap entry matching the environment
6448 width N: This integer value is the number of characters on a line.
6449 Default is 80, the current `stty cols'' setting, or the ``co#''
6450 setting from the termcap entry matching the environment
6453 Note: ``set screensize'' is obsolete. Use ``set height'' and
6454 ``set width'' instead.
6456 print address on/off: Print memory addresses in various command displays,
6457 such as stack traces and structure values. Gdb looks
6458 more ``symbolic'' if you turn this off; it looks more
6459 ``machine level'' with it on. Default is ON.
6461 print array on/off: Prettyprint arrays. New convenient format! Default
6464 print demangle on/off: Print C++ symbols in "source" form if on,
6467 print asm-demangle on/off: Same, for assembler level printouts
6470 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6473 * Support for Epoch Environment.
6475 The epoch environment is a version of Emacs v18 with windowing. One
6476 new command, ``inspect'', is identical to ``print'', except that if you
6477 are running in the epoch environment, the value is printed in its own
6481 * Support for Shared Libraries
6483 GDB can now debug programs and core files that use SunOS shared libraries.
6484 Symbols from a shared library cannot be referenced
6485 before the shared library has been linked with the program (this
6486 happens after you type ``run'' and before the function main() is entered).
6487 At any time after this linking (including when examining core files
6488 from dynamically linked programs), gdb reads the symbols from each
6489 shared library when you type the ``sharedlibrary'' command.
6490 It can be abbreviated ``share''.
6492 sharedlibrary REGEXP: Load shared object library symbols for files
6493 matching a unix regular expression. No argument
6494 indicates to load symbols for all shared libraries.
6496 info sharedlibrary: Status of loaded shared libraries.
6501 A watchpoint stops execution of a program whenever the value of an
6502 expression changes. Checking for this slows down execution
6503 tremendously whenever you are in the scope of the expression, but is
6504 quite useful for catching tough ``bit-spreader'' or pointer misuse
6505 problems. Some machines such as the 386 have hardware for doing this
6506 more quickly, and future versions of gdb will use this hardware.
6508 watch EXP: Set a watchpoint (breakpoint) for an expression.
6510 info watchpoints: Information about your watchpoints.
6512 delete N: Deletes watchpoint number N (same as breakpoints).
6513 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6514 enable N: Re-enables watchpoint number N (same as breakpoints).
6517 * C++ multiple inheritance
6519 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6522 * C++ exception handling
6524 Gdb now supports limited C++ exception handling. Besides the existing
6525 ability to breakpoint on an exception handler, gdb can breakpoint on
6526 the raising of an exception (before the stack is peeled back to the
6529 catch FOO: If there is a FOO exception handler in the dynamic scope,
6530 set a breakpoint to catch exceptions which may be raised there.
6531 Multiple exceptions (``catch foo bar baz'') may be caught.
6533 info catch: Lists all exceptions which may be caught in the
6534 current stack frame.
6537 * Minor command changes
6539 The command ``call func (arg, arg, ...)'' now acts like the print
6540 command, except it does not print or save a value if the function's result
6541 is void. This is similar to dbx usage.
6543 The ``up'' and ``down'' commands now always print the frame they end up
6544 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6545 frames without printing.
6547 * New directory command
6549 'dir' now adds directories to the FRONT of the source search path.
6550 The path starts off empty. Source files that contain debug information
6551 about the directory in which they were compiled can be found even
6552 with an empty path; Sun CC and GCC include this information. If GDB can't
6553 find your source file in the current directory, type "dir .".
6555 * Configuring GDB for compilation
6557 For normal use, type ``./configure host''. See README or gdb.texinfo
6560 GDB now handles cross debugging. If you are remotely debugging between
6561 two different machines, type ``./configure host -target=targ''.
6562 Host is the machine where GDB will run; targ is the machine
6563 where the program that you are debugging will run.