1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.12
6 * GDB and GDBserver now require building with a C++ compiler.
8 It is no longer possible to build GDB or GDBserver with a C
9 compiler. The --disable-build-with-cxx configure option has been
12 * Support for thread names on MS-Windows.
14 GDB now catches and handles the special exception that programs
15 running on MS-Windows use to assign names to threads in the
18 *** Changes in GDB 7.12
20 * GDB and GDBserver now build with a C++ compiler by default.
22 The --enable-build-with-cxx configure option is now enabled by
23 default. One must now explicitly configure with
24 --disable-build-with-cxx in order to build with a C compiler. This
25 option will be removed in a future release.
27 * GDBserver now supports recording btrace without maintaining an active
30 * GDB now supports a negative repeat count in the 'x' command to examine
31 memory backward from the given address. For example:
34 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
35 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
36 (gdb) x/-5i 0x0000000000400580
37 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
38 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
39 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
40 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
41 0x40057b <main(int, char**)+25>:
42 callq 0x400536 <Func1(int, char const*)>
44 * Fortran: Support structures with fields of dynamic types and
45 arrays of dynamic types.
47 * GDB now supports multibit bitfields and enums in target register
50 * New Python-based convenience function $_as_string(val), which returns
51 the textual representation of a value. This function is especially
52 useful to obtain the text label of an enum value.
54 * Intel MPX bound violation handling.
56 Segmentation faults caused by a Intel MPX boundary violation
57 now display the kind of violation (upper or lower), the memory
58 address accessed and the memory bounds, along with the usual
59 signal received and code location.
63 Program received signal SIGSEGV, Segmentation fault
64 Upper bound violation while accessing address 0x7fffffffc3b3
65 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
66 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
68 * Rust language support.
69 GDB now supports debugging programs written in the Rust programming
70 language. See https://www.rust-lang.org/ for more information about
73 * Support for running interpreters on specified input/output devices
75 GDB now supports a new mechanism that allows frontends to provide
76 fully featured GDB console views, as a better alternative to
77 building such views on top of the "-interpreter-exec console"
78 command. See the new "new-ui" command below. With that command,
79 frontends can now start GDB in the traditional command-line mode
80 running in an embedded terminal emulator widget, and create a
81 separate MI interpreter running on a specified i/o device. In this
82 way, GDB handles line editing, history, tab completion, etc. in the
83 console all by itself, and the GUI uses the separate MI interpreter
84 for its own control and synchronization, invisible to the command
87 * The "catch syscall" command catches groups of related syscalls.
89 The "catch syscall" command now supports catching a group of related
90 syscalls using the 'group:' or 'g:' prefix.
95 skip -gfile file-glob-pattern
96 skip -function function
97 skip -rfunction regular-expression
98 A generalized form of the skip command, with new support for
99 glob-style file names and regular expressions for function names.
100 Additionally, a file spec and a function spec may now be combined.
102 maint info line-table REGEXP
103 Display the contents of GDB's internal line table data struture.
106 Run any GDB unit tests that were compiled in.
109 Start a new user interface instance running INTERP as interpreter,
110 using the TTY file for input/output.
114 ** gdb.Breakpoint objects have a new attribute "pending", which
115 indicates whether the breakpoint is pending.
116 ** Three new breakpoint-related events have been added:
117 gdb.breakpoint_created, gdb.breakpoint_modified, and
118 gdb.breakpoint_deleted.
121 Signal ("set") the given MS-Windows event object. This is used in
122 conjunction with the Windows JIT debugging (AeDebug) support, where
123 the OS suspends a crashing process until a debugger can attach to
124 it. Resuming the crashing process, in order to debug it, is done by
127 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
128 was added in GDBserver, including JIT compiling fast tracepoint's
129 conditional expression bytecode into native code.
131 * Support for various remote target protocols and ROM monitors has
134 target m32rsdi Remote M32R debugging over SDI
135 target mips MIPS remote debugging protocol
136 target pmon PMON ROM monitor
137 target ddb NEC's DDB variant of PMON for Vr4300
138 target rockhopper NEC RockHopper variant of PMON
139 target lsi LSI variant of PMO
141 * Support for tracepoints and fast tracepoints on powerpc-linux,
142 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
143 including JIT compiling fast tracepoint's conditional expression
144 bytecode into native code.
146 * MI async record =record-started now includes the method and format used for
147 recording. For example:
149 =record-started,thread-group="i1",method="btrace",format="bts"
153 Andes NDS32 nds32*-*-elf
155 *** Changes in GDB 7.11
157 * GDB now supports debugging kernel-based threads on FreeBSD.
159 * Per-inferior thread numbers
161 Thread numbers are now per inferior instead of global. If you're
162 debugging multiple inferiors, GDB displays thread IDs using a
163 qualified INF_NUM.THR_NUM form. For example:
167 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
168 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
169 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
170 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
172 As consequence, thread numbers as visible in the $_thread
173 convenience variable and in Python's InferiorThread.num attribute
174 are no longer unique between inferiors.
176 GDB now maintains a second thread ID per thread, referred to as the
177 global thread ID, which is the new equivalent of thread numbers in
178 previous releases. See also $_gthread below.
180 For backwards compatibility, MI's thread IDs always refer to global
183 * Commands that accept thread IDs now accept the qualified
184 INF_NUM.THR_NUM form as well. For example:
187 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
190 * In commands that accept a list of thread IDs, you can now refer to
191 all threads of an inferior using a star wildcard. GDB accepts
192 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
193 refer to all threads of the current inferior. For example, "info
196 * You can use "info threads -gid" to display the global thread ID of
199 * The new convenience variable $_gthread holds the global number of
202 * The new convenience variable $_inferior holds the number of the
205 * GDB now displays the ID and name of the thread that hit a breakpoint
206 or received a signal, if your program is multi-threaded. For
209 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
210 Thread 1 "main" received signal SIGINT, Interrupt.
212 * Record btrace now supports non-stop mode.
214 * Support for tracepoints on aarch64-linux was added in GDBserver.
216 * The 'record instruction-history' command now indicates speculative execution
217 when using the Intel Processor Trace recording format.
219 * GDB now allows users to specify explicit locations, bypassing
220 the linespec parser. This feature is also available to GDB/MI
223 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
224 GDB now is able to debug both AArch64 applications and ARM applications
227 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
228 including JIT compiling fast tracepoint's conditional expression bytecode
231 * GDB now supports displaced stepping on AArch64 GNU/Linux.
233 * "info threads", "info inferiors", "info display", "info checkpoints"
234 and "maint info program-spaces" now list the corresponding items in
235 ascending ID order, for consistency with all other "info" commands.
237 * In Ada, the overloads selection menu has been enhanced to display the
238 parameter types and the return types for the matching overloaded subprograms.
242 maint set target-non-stop (on|off|auto)
243 maint show target-non-stop
244 Control whether GDB targets always operate in non-stop mode even if
245 "set non-stop" is "off". The default is "auto", meaning non-stop
246 mode is enabled if supported by the target.
248 maint set bfd-sharing
249 maint show bfd-sharing
250 Control the reuse of bfd objects.
254 Control display of debugging info regarding bfd caching.
258 Control display of debugging info regarding FreeBSD threads.
260 set remote multiprocess-extensions-packet
261 show remote multiprocess-extensions-packet
262 Set/show the use of the remote protocol multiprocess extensions.
264 set remote thread-events
265 show remote thread-events
266 Set/show the use of thread create/exit events.
268 set ada print-signatures on|off
269 show ada print-signatures"
270 Control whether parameter types and return types are displayed in overloads
271 selection menus. It is activaled (@code{on}) by default.
275 Controls the maximum size of memory, in bytes, that GDB will
276 allocate for value contents. Prevents incorrect programs from
277 causing GDB to allocate overly large buffers. Default is 64k.
279 * The "disassemble" command accepts a new modifier: /s.
280 It prints mixed source+disassembly like /m with two differences:
281 - disassembled instructions are now printed in program order, and
282 - and source for all relevant files is now printed.
283 The "/m" option is now considered deprecated: its "source-centric"
284 output hasn't proved useful in practice.
286 * The "record instruction-history" command accepts a new modifier: /s.
287 It behaves exactly like /m and prints mixed source+disassembly.
289 * The "set scheduler-locking" command supports a new mode "replay".
290 It behaves like "off" in record mode and like "on" in replay mode.
292 * Support for various ROM monitors has been removed:
294 target dbug dBUG ROM monitor for Motorola ColdFire
295 target picobug Motorola picobug monitor
296 target dink32 DINK32 ROM monitor for PowerPC
297 target m32r Renesas M32R/D ROM monitor
298 target mon2000 mon2000 ROM monitor
299 target ppcbug PPCBUG ROM monitor for PowerPC
301 * Support for reading/writing memory and extracting values on architectures
302 whose memory is addressable in units of any integral multiple of 8 bits.
307 Indicates that an exec system call was executed.
309 exec-events feature in qSupported
310 The qSupported packet allows GDB to request support for exec
311 events using the new 'gdbfeature' exec-event, and the qSupported
312 response can contain the corresponding 'stubfeature'. Set and
313 show commands can be used to display whether these features are enabled.
316 Equivalent to interrupting with the ^C character, but works in
319 thread created stop reason (T05 create:...)
320 Indicates that the thread was just created and is stopped at entry.
322 thread exit stop reply (w exitcode;tid)
323 Indicates that the thread has terminated.
326 Enables/disables thread create and exit event reporting. For
327 example, this is used in non-stop mode when GDB stops a set of
328 threads and synchronously waits for the their corresponding stop
329 replies. Without exit events, if one of the threads exits, GDB
330 would hang forever not knowing that it should no longer expect a
331 stop for that same thread.
334 Indicates that there are no resumed threads left in the target (all
335 threads are stopped). The remote stub reports support for this stop
336 reply to GDB's qSupported query.
339 Enables/disables catching syscalls from the inferior process.
340 The remote stub reports support for this packet to GDB's qSupported query.
342 syscall_entry stop reason
343 Indicates that a syscall was just called.
345 syscall_return stop reason
346 Indicates that a syscall just returned.
348 * Extended-remote exec events
350 ** GDB now has support for exec events on extended-remote Linux targets.
351 For such targets with Linux kernels 2.5.46 and later, this enables
352 follow-exec-mode and exec catchpoints.
354 set remote exec-event-feature-packet
355 show remote exec-event-feature-packet
356 Set/show the use of the remote exec event feature.
358 * Thread names in remote protocol
360 The reply to qXfer:threads:read may now include a name attribute for each
363 * Target remote mode fork and exec events
365 ** GDB now has support for fork and exec events on target remote mode
366 Linux targets. For such targets with Linux kernels 2.5.46 and later,
367 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
368 fork and exec catchpoints.
370 * Remote syscall events
372 ** GDB now has support for catch syscall on remote Linux targets,
373 currently enabled on x86/x86_64 architectures.
375 set remote catch-syscall-packet
376 show remote catch-syscall-packet
377 Set/show the use of the remote catch syscall feature.
381 ** The -var-set-format command now accepts the zero-hexadecimal
382 format. It outputs data in hexadecimal format with zero-padding on the
387 ** gdb.InferiorThread objects have a new attribute "global_num",
388 which refers to the thread's global thread ID. The existing
389 "num" attribute now refers to the thread's per-inferior number.
390 See "Per-inferior thread numbers" above.
391 ** gdb.InferiorThread objects have a new attribute "inferior", which
392 is the Inferior object the thread belongs to.
394 *** Changes in GDB 7.10
396 * Support for process record-replay and reverse debugging on aarch64*-linux*
397 targets has been added. GDB now supports recording of A64 instruction set
398 including advance SIMD instructions.
400 * Support for Sun's version of the "stabs" debug file format has been removed.
402 * GDB now honors the content of the file /proc/PID/coredump_filter
403 (PID is the process ID) on GNU/Linux systems. This file can be used
404 to specify the types of memory mappings that will be included in a
405 corefile. For more information, please refer to the manual page of
406 "core(5)". GDB also has a new command: "set use-coredump-filter
407 on|off". It allows to set whether GDB will read the content of the
408 /proc/PID/coredump_filter file when generating a corefile.
410 * The "info os" command on GNU/Linux can now display information on
412 "info os cpus" Listing of all cpus/cores on the system
414 * GDB has two new commands: "set serial parity odd|even|none" and
415 "show serial parity". These allows to set or show parity for the
418 * The "info source" command now displays the producer string if it was
419 present in the debug info. This typically includes the compiler version
420 and may include things like its command line arguments.
422 * The "info dll", an alias of the "info sharedlibrary" command,
423 is now available on all platforms.
425 * Directory names supplied to the "set sysroot" commands may be
426 prefixed with "target:" to tell GDB to access shared libraries from
427 the target system, be it local or remote. This replaces the prefix
428 "remote:". The default sysroot has been changed from "" to
429 "target:". "remote:" is automatically converted to "target:" for
430 backward compatibility.
432 * The system root specified by "set sysroot" will be prepended to the
433 filename of the main executable (if reported to GDB as absolute by
434 the operating system) when starting processes remotely, and when
435 attaching to already-running local or remote processes.
437 * GDB now supports automatic location and retrieval of executable
438 files from remote targets. Remote debugging can now be initiated
439 using only a "target remote" or "target extended-remote" command
440 (no "set sysroot" or "file" commands are required). See "New remote
443 * The "dump" command now supports verilog hex format.
445 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
447 * On GNU/Linux, GDB and gdbserver are now able to access executable
448 and shared library files without a "set sysroot" command when
449 attaching to processes running in different mount namespaces from
450 the debugger. This makes it possible to attach to processes in
451 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
452 See "New remote packets" below.
454 * The "tui reg" command now provides completion for all of the
455 available register groups, including target specific groups.
457 * The HISTSIZE environment variable is no longer read when determining
458 the size of GDB's command history. GDB now instead reads the dedicated
459 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
460 disables truncation of command history. Non-numeric values of GDBHISTSIZE
465 ** Memory ports can now be unbuffered.
469 ** gdb.Objfile objects have a new attribute "username",
470 which is the name of the objfile as specified by the user,
471 without, for example, resolving symlinks.
472 ** You can now write frame unwinders in Python.
473 ** gdb.Type objects have a new method "optimized_out",
474 returning optimized out gdb.Value instance of this type.
475 ** gdb.Value objects have new methods "reference_value" and
476 "const_value" which return a reference to the value and a
477 "const" version of the value respectively.
481 maint print symbol-cache
482 Print the contents of the symbol cache.
484 maint print symbol-cache-statistics
485 Print statistics of symbol cache usage.
487 maint flush-symbol-cache
488 Flush the contents of the symbol cache.
492 Start branch trace recording using Branch Trace Store (BTS) format.
495 Evaluate expression by using the compiler and print result.
499 Explicit commands for enabling and disabling tui mode.
502 set mpx bound on i386 and amd64
503 Support for bound table investigation on Intel MPX enabled applications.
507 Start branch trace recording using Intel Processor Trace format.
510 Print information about branch tracing internals.
512 maint btrace packet-history
513 Print the raw branch tracing data.
515 maint btrace clear-packet-history
516 Discard the stored raw branch tracing data.
519 Discard all branch tracing data. It will be fetched and processed
520 anew by the next "record" command.
525 Renamed from "set debug dwarf2-die".
527 Renamed from "show debug dwarf2-die".
530 Renamed from "set debug dwarf2-read".
531 show debug dwarf-read
532 Renamed from "show debug dwarf2-read".
534 maint set dwarf always-disassemble
535 Renamed from "maint set dwarf2 always-disassemble".
536 maint show dwarf always-disassemble
537 Renamed from "maint show dwarf2 always-disassemble".
539 maint set dwarf max-cache-age
540 Renamed from "maint set dwarf2 max-cache-age".
541 maint show dwarf max-cache-age
542 Renamed from "maint show dwarf2 max-cache-age".
545 show debug dwarf-line
546 Control display of debugging info regarding DWARF line processing.
550 Set the maximum number of candidates to be considered during
551 completion. The default value is 200. This limit allows GDB
552 to avoid generating large completion lists, the computation of
553 which can cause the debugger to become temporarily unresponsive.
555 set history remove-duplicates
556 show history remove-duplicates
557 Control the removal of duplicate history entries.
559 maint set symbol-cache-size
560 maint show symbol-cache-size
561 Control the size of the symbol cache.
563 set|show record btrace bts buffer-size
564 Set and show the size of the ring buffer used for branch tracing in
566 The obtained size may differ from the requested size. Use "info
567 record" to see the obtained buffer size.
569 set debug linux-namespaces
570 show debug linux-namespaces
571 Control display of debugging info regarding Linux namespaces.
573 set|show record btrace pt buffer-size
574 Set and show the size of the ring buffer used for branch tracing in
575 Intel Processor Trace format.
576 The obtained size may differ from the requested size. Use "info
577 record" to see the obtained buffer size.
579 maint set|show btrace pt skip-pad
580 Set and show whether PAD packets are skipped when computing the
583 * The command 'thread apply all' can now support new option '-ascending'
584 to call its specified command for all threads in ascending order.
586 * Python/Guile scripting
588 ** GDB now supports auto-loading of Python/Guile scripts contained in the
589 special section named `.debug_gdb_scripts'.
593 qXfer:btrace-conf:read
594 Return the branch trace configuration for the current thread.
596 Qbtrace-conf:bts:size
597 Set the requested ring buffer size for branch tracing in BTS format.
600 Enable Intel Procesor Trace-based branch tracing for the current
601 process. The remote stub reports support for this packet to GDB's
605 Set the requested ring buffer size for branch tracing in Intel Processor
609 Indicates a memory breakpoint instruction was executed, irrespective
610 of whether it was GDB that planted the breakpoint or the breakpoint
611 is hardcoded in the program. This is required for correct non-stop
615 Indicates the target stopped for a hardware breakpoint. This is
616 required for correct non-stop mode operation.
619 Return information about files on the remote system.
622 Return the full absolute name of the file that was executed to
623 create a process running on the remote system.
626 Select the filesystem on which vFile: operations with filename
627 arguments will operate. This is required for GDB to be able to
628 access files on remote targets where the remote stub does not
629 share a common filesystem with the inferior(s).
632 Indicates that a fork system call was executed.
635 Indicates that a vfork system call was executed.
637 vforkdone stop reason
638 Indicates that a vfork child of the specified process has executed
639 an exec or exit, allowing the vfork parent to resume execution.
641 fork-events and vfork-events features in qSupported
642 The qSupported packet allows GDB to request support for fork and
643 vfork events using new 'gdbfeatures' fork-events and vfork-events,
644 and the qSupported response can contain the corresponding
645 'stubfeatures'. Set and show commands can be used to display
646 whether these features are enabled.
648 * Extended-remote fork events
650 ** GDB now has support for fork events on extended-remote Linux
651 targets. For targets with Linux kernels 2.5.60 and later, this
652 enables follow-fork-mode and detach-on-fork for both fork and
653 vfork, as well as fork and vfork catchpoints.
655 * The info record command now shows the recording format and the
656 branch tracing configuration for the current thread when using
657 the btrace record target.
658 For the BTS format, it shows the ring buffer size.
660 * GDB now has support for DTrace USDT (Userland Static Defined
661 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
663 * GDB now supports access to vector registers on S/390 GNU/Linux
666 * Removed command line options
668 -xdb HP-UX XDB compatibility mode.
670 * Removed targets and native configurations
672 HP/PA running HP-UX hppa*-*-hpux*
673 Itanium running HP-UX ia64-*-hpux*
675 * New configure options
678 This configure option allows the user to build GDB with support for
679 Intel Processor Trace (default: auto). This requires libipt.
681 --with-libipt-prefix=PATH
682 Specify the path to the version of libipt that GDB should use.
683 $PATH/include should contain the intel-pt.h header and
684 $PATH/lib should contain the libipt.so library.
686 *** Changes in GDB 7.9.1
690 ** Xmethods can now specify a result type.
692 *** Changes in GDB 7.9
694 * GDB now supports hardware watchpoints on x86 GNU Hurd.
698 ** You can now access frame registers from Python scripts.
699 ** New attribute 'producer' for gdb.Symtab objects.
700 ** gdb.Objfile objects have a new attribute "progspace",
701 which is the gdb.Progspace object of the containing program space.
702 ** gdb.Objfile objects have a new attribute "owner".
703 ** gdb.Objfile objects have a new attribute "build_id",
704 which is the build ID generated when the file was built.
705 ** gdb.Objfile objects have a new method "add_separate_debug_file".
706 ** A new event "gdb.clear_objfiles" has been added, triggered when
707 selecting a new file to debug.
708 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
709 ** New function gdb.lookup_objfile.
711 New events which are triggered when GDB modifies the state of the
714 ** gdb.events.inferior_call_pre: Function call is about to be made.
715 ** gdb.events.inferior_call_post: Function call has just been made.
716 ** gdb.events.memory_changed: A memory location has been altered.
717 ** gdb.events.register_changed: A register has been altered.
719 * New Python-based convenience functions:
721 ** $_caller_is(name [, number_of_frames])
722 ** $_caller_matches(regexp [, number_of_frames])
723 ** $_any_caller_is(name [, number_of_frames])
724 ** $_any_caller_matches(regexp [, number_of_frames])
726 * GDB now supports the compilation and injection of source code into
727 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
728 to compile the source code to object code, and if successful, inject
729 and execute that code within the current context of the inferior.
730 Currently the C language is supported. The commands used to
731 interface with this new feature are:
733 compile code [-raw|-r] [--] [source code]
734 compile file [-raw|-r] filename
738 demangle [-l language] [--] name
739 Demangle "name" in the specified language, or the current language
740 if elided. This command is renamed from the "maint demangle" command.
741 The latter is kept as a no-op to avoid "maint demangle" being interpreted
742 as "maint demangler-warning".
744 queue-signal signal-name-or-number
745 Queue a signal to be delivered to the thread when it is resumed.
747 add-auto-load-scripts-directory directory
748 Add entries to the list of directories from which to load auto-loaded
751 maint print user-registers
752 List all currently available "user" registers.
754 compile code [-r|-raw] [--] [source code]
755 Compile, inject, and execute in the inferior the executable object
756 code produced by compiling the provided source code.
758 compile file [-r|-raw] filename
759 Compile and inject into the inferior the executable object code
760 produced by compiling the source code stored in the filename
763 * On resume, GDB now always passes the signal the program had stopped
764 for to the thread the signal was sent to, even if the user changed
765 threads before resuming. Previously GDB would often (but not
766 always) deliver the signal to the thread that happens to be current
769 * Conversely, the "signal" command now consistently delivers the
770 requested signal to the current thread. GDB now asks for
771 confirmation if the program had stopped for a signal and the user
772 switched threads meanwhile.
774 * "breakpoint always-inserted" modes "off" and "auto" merged.
776 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
777 won't remove breakpoints from the target until all threads stop,
778 even in non-stop mode. The "auto" mode has been removed, and "off"
779 is now the default mode.
783 set debug symbol-lookup
784 show debug symbol-lookup
785 Control display of debugging info regarding symbol lookup.
789 ** The -list-thread-groups command outputs an exit-code field for
790 inferiors that have exited.
794 MIPS SDE mips*-sde*-elf*
798 Support for these obsolete configurations has been removed.
800 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
801 SGI Irix-5.x mips-*-irix5*
802 SGI Irix-6.x mips-*-irix6*
803 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
804 VAX running Ultrix vax-*-ultrix*
806 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
807 and "assf"), have been removed. Use the "sharedlibrary" command, or
808 its alias "share", instead.
810 *** Changes in GDB 7.8
812 * New command line options
815 This is an alias for the --data-directory option.
817 * GDB supports printing and modifying of variable length automatic arrays
818 as specified in ISO C99.
820 * The ARM simulator now supports instruction level tracing
821 with or without disassembly.
825 GDB now has support for scripting using Guile. Whether this is
826 available is determined at configure time.
827 Guile version 2.0 or greater is required.
828 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
830 * New commands (for set/show, see "New options" below)
834 Invoke CODE by passing it to the Guile interpreter.
838 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
840 info auto-load guile-scripts [regexp]
841 Print the list of automatically loaded Guile scripts.
843 * The source command is now capable of sourcing Guile scripts.
844 This feature is dependent on the debugger being built with Guile support.
848 set print symbol-loading (off|brief|full)
849 show print symbol-loading
850 Control whether to print informational messages when loading symbol
851 information for a file. The default is "full", but when debugging
852 programs with large numbers of shared libraries the amount of output
855 set guile print-stack (none|message|full)
856 show guile print-stack
857 Show a stack trace when an error is encountered in a Guile script.
859 set auto-load guile-scripts (on|off)
860 show auto-load guile-scripts
861 Control auto-loading of Guile script files.
863 maint ada set ignore-descriptive-types (on|off)
864 maint ada show ignore-descriptive-types
865 Control whether the debugger should ignore descriptive types in Ada
866 programs. The default is not to ignore the descriptive types. See
867 the user manual for more details on descriptive types and the intended
868 usage of this option.
870 set auto-connect-native-target
872 Control whether GDB is allowed to automatically connect to the
873 native target for the run, attach, etc. commands when not connected
874 to any target yet. See also "target native" below.
876 set record btrace replay-memory-access (read-only|read-write)
877 show record btrace replay-memory-access
878 Control what memory accesses are allowed during replay.
880 maint set target-async (on|off)
881 maint show target-async
882 This controls whether GDB targets operate in synchronous or
883 asynchronous mode. Normally the default is asynchronous, if it is
884 available; but this can be changed to more easily debug problems
885 occurring only in synchronous mode.
887 set mi-async (on|off)
889 Control whether MI asynchronous mode is preferred. This supersedes
890 "set target-async" of previous GDB versions.
892 * "set target-async" is deprecated as a CLI option and is now an alias
893 for "set mi-async" (only puts MI into async mode).
895 * Background execution commands (e.g., "c&", "s&", etc.) are now
896 possible ``out of the box'' if the target supports them. Previously
897 the user would need to explicitly enable the possibility with the
898 "set target-async on" command.
900 * New features in the GDB remote stub, GDBserver
902 ** New option --debug-format=option1[,option2,...] allows one to add
903 additional text to each output. At present only timestamps
904 are supported: --debug-format=timestamps.
905 Timestamps can also be turned on with the
906 "monitor set debug-format timestamps" command from GDB.
908 * The 'record instruction-history' command now starts counting instructions
909 at one. This also affects the instruction ranges reported by the
910 'record function-call-history' command when given the /i modifier.
912 * The command 'record function-call-history' supports a new modifier '/c' to
913 indent the function names based on their call stack depth.
914 The fields for the '/i' and '/l' modifier have been reordered.
915 The source line range is now prefixed with 'at'.
916 The instruction range is now prefixed with 'inst'.
917 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
918 "record instruction-history" and "list" commands.
920 * The ranges given as arguments to the 'record function-call-history' and
921 'record instruction-history' commands are now inclusive.
923 * The btrace record target now supports the 'record goto' command.
924 For locations inside the execution trace, the back trace is computed
925 based on the information stored in the execution trace.
927 * The btrace record target supports limited reverse execution and replay.
928 The target does not record data and therefore does not allow reading
931 * The "catch syscall" command now works on s390*-linux* targets.
933 * The "compare-sections" command is no longer specific to target
934 remote. It now works with all targets.
936 * All native targets are now consistently called "native".
937 Consequently, the "target child", "target GNU", "target djgpp",
938 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
939 commands have been replaced with "target native". The QNX/NTO port
940 leaves the "procfs" target in place and adds a "native" target for
941 consistency with other ports. The impact on users should be minimal
942 as these commands previously either throwed an error, or were
943 no-ops. The target's name is visible in the output of the following
944 commands: "help target", "info target", "info files", "maint print
947 * The "target native" command now connects to the native target. This
948 can be used to launch native programs even when "set
949 auto-connect-native-target" is set to off.
951 * GDB now supports access to Intel MPX registers on GNU/Linux.
953 * Support for Intel AVX-512 registers on GNU/Linux.
954 Support displaying and modifying Intel AVX-512 registers
955 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
959 qXfer:btrace:read's annex
960 The qXfer:btrace:read packet supports a new annex 'delta' to read
961 branch trace incrementally.
965 ** Valid Python operations on gdb.Value objects representing
966 structs/classes invoke the corresponding overloaded operators if
968 ** New `Xmethods' feature in the Python API. Xmethods are
969 additional methods or replacements for existing methods of a C++
970 class. This feature is useful for those cases where a method
971 defined in C++ source code could be inlined or optimized out by
972 the compiler, making it unavailable to GDB.
975 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
977 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
978 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
979 its alias "share", instead.
981 * The commands "set remotebaud" and "show remotebaud" are no longer
982 supported. Use "set serial baud" and "show serial baud" (respectively)
987 ** A new option "-gdb-set mi-async" replaces "-gdb-set
988 target-async". The latter is left as a deprecated alias of the
989 former for backward compatibility. If the target supports it,
990 CLI background execution commands are now always possible by
991 default, independently of whether the frontend stated a
992 preference for asynchronous execution with "-gdb-set mi-async".
993 Previously "-gdb-set target-async off" affected both MI execution
994 commands and CLI execution commands.
996 *** Changes in GDB 7.7
998 * Improved support for process record-replay and reverse debugging on
999 arm*-linux* targets. Support for thumb32 and syscall instruction
1000 recording has been added.
1002 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1004 * GDB now supports Fission DWP file format version 2.
1005 http://gcc.gnu.org/wiki/DebugFission
1007 * New convenience function "$_isvoid", to check whether an expression
1008 is void. A void expression is an expression where the type of the
1009 result is "void". For example, some convenience variables may be
1010 "void" when evaluated (e.g., "$_exitcode" before the execution of
1011 the program being debugged; or an undefined convenience variable).
1012 Another example, when calling a function whose return type is
1015 * The "maintenance print objfiles" command now takes an optional regexp.
1017 * The "catch syscall" command now works on arm*-linux* targets.
1019 * GDB now consistently shows "<not saved>" when printing values of
1020 registers the debug info indicates have not been saved in the frame
1021 and there's nowhere to retrieve them from
1022 (callee-saved/call-clobbered registers):
1027 (gdb) info registers rax
1030 Before, the former would print "<optimized out>", and the latter
1031 "*value not available*".
1033 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1038 ** Frame filters and frame decorators have been added.
1039 ** Temporary breakpoints are now supported.
1040 ** Line tables representation has been added.
1041 ** New attribute 'parent_type' for gdb.Field objects.
1042 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1043 ** New attribute 'name' for gdb.Type objects.
1047 Nios II ELF nios2*-*-elf
1048 Nios II GNU/Linux nios2*-*-linux
1049 Texas Instruments MSP430 msp430*-*-elf
1051 * Removed native configurations
1053 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1054 been removed. ELF variants of these configurations are kept supported.
1056 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1057 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1058 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1059 i[34567]86-*-openbsd3.[0-3]
1060 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1061 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1062 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1066 Like "catch throw", but catches a re-thrown exception.
1067 maint check-psymtabs
1068 Renamed from old "maint check-symtabs".
1070 Perform consistency checks on symtabs.
1071 maint expand-symtabs
1072 Expand symtabs matching an optional regexp.
1075 Display the details of GDB configure-time options.
1077 maint set|show per-command
1078 maint set|show per-command space
1079 maint set|show per-command time
1080 maint set|show per-command symtab
1081 Enable display of per-command gdb resource usage.
1083 remove-symbol-file FILENAME
1084 remove-symbol-file -a ADDRESS
1085 Remove a symbol file added via add-symbol-file. The file to remove
1086 can be identified by its filename or by an address that lies within
1087 the boundaries of this symbol file in memory.
1090 info exceptions REGEXP
1091 Display the list of Ada exceptions defined in the program being
1092 debugged. If provided, only the exceptions whose names match REGEXP
1097 set debug symfile off|on
1099 Control display of debugging info regarding reading symbol files and
1100 symbol tables within those files
1102 set print raw frame-arguments
1103 show print raw frame-arguments
1104 Set/show whether to print frame arguments in raw mode,
1105 disregarding any defined pretty-printers.
1107 set remote trace-status-packet
1108 show remote trace-status-packet
1109 Set/show the use of remote protocol qTStatus packet.
1113 Control display of debugging messages related to Nios II targets.
1117 Control whether target-assisted range stepping is enabled.
1119 set startup-with-shell
1120 show startup-with-shell
1121 Specifies whether Unix child processes are started via a shell or
1126 Use the target memory cache for accesses to the code segment. This
1127 improves performance of remote debugging (particularly disassembly).
1129 * You can now use a literal value 'unlimited' for options that
1130 interpret 0 or -1 as meaning "unlimited". E.g., "set
1131 trace-buffer-size unlimited" is now an alias for "set
1132 trace-buffer-size -1" and "set height unlimited" is now an alias for
1135 * The "set debug symtab-create" debugging option of GDB has been changed to
1136 accept a verbosity level. 0 means "off", 1 provides basic debugging
1137 output, and values of 2 or greater provides more verbose output.
1139 * New command-line options
1141 Display the details of GDB configure-time options.
1143 * The command 'tsave' can now support new option '-ctf' to save trace
1144 buffer in Common Trace Format.
1146 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1149 * GDB now implements the the C++ 'typeid' operator.
1151 * The new convenience variable $_exception holds the exception being
1152 thrown or caught at an exception-related catchpoint.
1154 * The exception-related catchpoints, like "catch throw", now accept a
1155 regular expression which can be used to filter exceptions by type.
1157 * The new convenience variable $_exitsignal is automatically set to
1158 the terminating signal number when the program being debugged dies
1159 due to an uncaught signal.
1163 ** All MI commands now accept an optional "--language" option.
1164 Support for this feature can be verified by using the "-list-features"
1165 command, which should contain "language-option".
1167 ** The new command -info-gdb-mi-command allows the user to determine
1168 whether a GDB/MI command is supported or not.
1170 ** The "^error" result record returned when trying to execute an undefined
1171 GDB/MI command now provides a variable named "code" whose content is the
1172 "undefined-command" error code. Support for this feature can be verified
1173 by using the "-list-features" command, which should contain
1174 "undefined-command-error-code".
1176 ** The -trace-save MI command can optionally save trace buffer in Common
1179 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1181 ** The command -data-list-register-values now accepts an optional
1182 "--skip-unavailable" option. When used, only the available registers
1185 ** The new command -trace-frame-collected dumps collected variables,
1186 computed expressions, tvars, memory and registers in a traceframe.
1188 ** The commands -stack-list-locals, -stack-list-arguments and
1189 -stack-list-variables now accept an option "--skip-unavailable".
1190 When used, only the available locals or arguments are displayed.
1192 ** The -exec-run command now accepts an optional "--start" option.
1193 When used, the command follows the same semantics as the "start"
1194 command, stopping the program's execution at the start of its
1195 main subprogram. Support for this feature can be verified using
1196 the "-list-features" command, which should contain
1197 "exec-run-start-option".
1199 ** The new commands -catch-assert and -catch-exceptions insert
1200 catchpoints stopping the program when Ada exceptions are raised.
1202 ** The new command -info-ada-exceptions provides the equivalent of
1203 the new "info exceptions" command.
1205 * New system-wide configuration scripts
1206 A GDB installation now provides scripts suitable for use as system-wide
1207 configuration scripts for the following systems:
1211 * GDB now supports target-assigned range stepping with remote targets.
1212 This improves the performance of stepping source lines by reducing
1213 the number of control packets from/to GDB. See "New remote packets"
1216 * GDB now understands the element 'tvar' in the XML traceframe info.
1217 It has the id of the collected trace state variables.
1219 * On S/390 targets that provide the transactional-execution feature,
1220 the program interruption transaction diagnostic block (TDB) is now
1221 represented as a number of additional "registers" in GDB.
1223 * New remote packets
1227 The vCont packet supports a new 'r' action, that tells the remote
1228 stub to step through an address range itself, without GDB
1229 involvemement at each single-step.
1231 qXfer:libraries-svr4:read's annex
1232 The previously unused annex of the qXfer:libraries-svr4:read packet
1233 is now used to support passing an argument list. The remote stub
1234 reports support for this argument list to GDB's qSupported query.
1235 The defined arguments are "start" and "prev", used to reduce work
1236 necessary for library list updating, resulting in significant
1239 * New features in the GDB remote stub, GDBserver
1241 ** GDBserver now supports target-assisted range stepping. Currently
1242 enabled on x86/x86_64 GNU/Linux targets.
1244 ** GDBserver now adds element 'tvar' in the XML in the reply to
1245 'qXfer:traceframe-info:read'. It has the id of the collected
1246 trace state variables.
1248 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1251 * New 'z' formatter for printing and examining memory, this displays the
1252 value as hexadecimal zero padded on the left to the size of the type.
1254 * GDB can now use Windows x64 unwinding data.
1256 * The "set remotebaud" command has been replaced by "set serial baud".
1257 Similarly, "show remotebaud" has been replaced by "show serial baud".
1258 The "set remotebaud" and "show remotebaud" commands are still available
1259 to provide backward compatibility with older versions of GDB.
1261 *** Changes in GDB 7.6
1263 * Target record has been renamed to record-full.
1264 Record/replay is now enabled with the "record full" command.
1265 This also affects settings that are associated with full record/replay
1266 that have been moved from "set/show record" to "set/show record full":
1268 set|show record full insn-number-max
1269 set|show record full stop-at-limit
1270 set|show record full memory-query
1272 * A new record target "record-btrace" has been added. The new target
1273 uses hardware support to record the control-flow of a process. It
1274 does not support replaying the execution, but it implements the
1275 below new commands for investigating the recorded execution log.
1276 This new recording method can be enabled using:
1280 The "record-btrace" target is only available on Intel Atom processors
1281 and requires a Linux kernel 2.6.32 or later.
1283 * Two new commands have been added for record/replay to give information
1284 about the recorded execution without having to replay the execution.
1285 The commands are only supported by "record btrace".
1287 record instruction-history prints the execution history at
1288 instruction granularity
1290 record function-call-history prints the execution history at
1291 function granularity
1293 * New native configurations
1295 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1296 FreeBSD/powerpc powerpc*-*-freebsd
1297 x86_64/Cygwin x86_64-*-cygwin*
1298 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1302 ARM AArch64 aarch64*-*-elf
1303 ARM AArch64 GNU/Linux aarch64*-*-linux
1304 Lynx 178 PowerPC powerpc-*-lynx*178
1305 x86_64/Cygwin x86_64-*-cygwin*
1306 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1308 * If the configured location of system.gdbinit file (as given by the
1309 --with-system-gdbinit option at configure time) is in the
1310 data-directory (as specified by --with-gdb-datadir at configure
1311 time) or in one of its subdirectories, then GDB will look for the
1312 system-wide init file in the directory specified by the
1313 --data-directory command-line option.
1315 * New command line options:
1317 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1318 other initialization files, unlike -nx which disables all of them.
1320 * Removed command line options
1322 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1325 * The 'ptype' and 'whatis' commands now accept an argument to control
1328 * 'info proc' now works on some core files.
1332 ** Vectors can be created with gdb.Type.vector.
1334 ** Python's atexit.register now works in GDB.
1336 ** Types can be pretty-printed via a Python API.
1338 ** Python 3 is now supported (in addition to Python 2.4 or later)
1340 ** New class gdb.Architecture exposes GDB's internal representation
1341 of architecture in the Python API.
1343 ** New method Frame.architecture returns the gdb.Architecture object
1344 corresponding to the frame's architecture.
1346 * New Python-based convenience functions:
1348 ** $_memeq(buf1, buf2, length)
1349 ** $_streq(str1, str2)
1351 ** $_regex(str, regex)
1353 * The 'cd' command now defaults to using '~' (the home directory) if not
1356 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1357 default for GCC since November 2000.
1359 * The command 'forward-search' can now be abbreviated as 'fo'.
1361 * The command 'info tracepoints' can now display 'installed on target'
1362 or 'not installed on target' for each non-pending location of tracepoint.
1364 * New configure options
1366 --enable-libmcheck/--disable-libmcheck
1367 By default, development versions are built with -lmcheck on hosts
1368 that support it, in order to help track memory corruption issues.
1369 Release versions, on the other hand, are built without -lmcheck
1370 by default. The --enable-libmcheck/--disable-libmcheck configure
1371 options allow the user to override that default.
1372 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1373 This configure option allows the user to build GDB with
1374 libbabeltrace using which GDB can read Common Trace Format data.
1376 * New commands (for set/show, see "New options" below)
1379 Catch signals. This is similar to "handle", but allows commands and
1380 conditions to be attached.
1383 List the BFDs known to GDB.
1385 python-interactive [command]
1387 Start a Python interactive prompt, or evaluate the optional command
1388 and print the result of expressions.
1391 "py" is a new alias for "python".
1393 enable type-printer [name]...
1394 disable type-printer [name]...
1395 Enable or disable type printers.
1399 ** For the Renesas Super-H architecture, the "regs" command has been removed
1400 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1405 set print type methods (on|off)
1406 show print type methods
1407 Control whether method declarations are displayed by "ptype".
1408 The default is to show them.
1410 set print type typedefs (on|off)
1411 show print type typedefs
1412 Control whether typedef definitions are displayed by "ptype".
1413 The default is to show them.
1415 set filename-display basename|relative|absolute
1416 show filename-display
1417 Control the way in which filenames is displayed.
1418 The default is "relative", which preserves previous behavior.
1420 set trace-buffer-size
1421 show trace-buffer-size
1422 Request target to change the size of trace buffer.
1424 set remote trace-buffer-size-packet auto|on|off
1425 show remote trace-buffer-size-packet
1426 Control the use of the remote protocol `QTBuffer:size' packet.
1430 Control display of debugging messages related to ARM AArch64.
1433 set debug coff-pe-read
1434 show debug coff-pe-read
1435 Control display of debugging messages related to reading of COFF/PE
1440 Control display of debugging messages related to Mach-O symbols
1443 set debug notification
1444 show debug notification
1445 Control display of debugging info for async remote notification.
1449 ** Command parameter changes are now notified using new async record
1450 "=cmd-param-changed".
1451 ** Trace frame changes caused by command "tfind" are now notified using
1452 new async record "=traceframe-changed".
1453 ** The creation, deletion and modification of trace state variables
1454 are now notified using new async records "=tsv-created",
1455 "=tsv-deleted" and "=tsv-modified".
1456 ** The start and stop of process record are now notified using new
1457 async record "=record-started" and "=record-stopped".
1458 ** Memory changes are now notified using new async record
1460 ** The data-disassemble command response will include a "fullname" field
1461 containing the absolute file name when source has been requested.
1462 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1463 command, to allow pattern filling of memory areas.
1464 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1465 library load/unload events.
1466 ** The response to breakpoint commands and breakpoint async records
1467 includes an "installed" field containing a boolean state about each
1468 non-pending tracepoint location is whether installed on target or not.
1469 ** Output of the "-trace-status" command includes a "trace-file" field
1470 containing the name of the trace file being examined. This field is
1471 optional, and only present when examining a trace file.
1472 ** The "fullname" field is now always present along with the "file" field,
1473 even if the file cannot be found by GDB.
1475 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1476 You must have the LZMA library available when configuring GDB for this
1477 feature to be enabled. For more information, see:
1478 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1480 * New remote packets
1483 Set the size of trace buffer. The remote stub reports support for this
1484 packet to gdb's qSupported query.
1487 Enable Branch Trace Store (BTS)-based branch tracing for the current
1488 thread. The remote stub reports support for this packet to gdb's
1492 Disable branch tracing for the current thread. The remote stub reports
1493 support for this packet to gdb's qSupported query.
1496 Read the traced branches for the current thread. The remote stub
1497 reports support for this packet to gdb's qSupported query.
1499 *** Changes in GDB 7.5
1501 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1502 for more x32 ABI info.
1504 * GDB now supports access to MIPS DSP registers on Linux targets.
1506 * GDB now supports debugging microMIPS binaries.
1508 * The "info os" command on GNU/Linux can now display information on
1509 several new classes of objects managed by the operating system:
1510 "info os procgroups" lists process groups
1511 "info os files" lists file descriptors
1512 "info os sockets" lists internet-domain sockets
1513 "info os shm" lists shared-memory regions
1514 "info os semaphores" lists semaphores
1515 "info os msg" lists message queues
1516 "info os modules" lists loaded kernel modules
1518 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1519 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1520 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1521 options and inspect the probe arguments using the new $_probe_arg family
1522 of convenience variables. You can obtain more information about SystemTap
1523 in <http://sourceware.org/systemtap/>.
1525 * GDB now supports reversible debugging on ARM, it allows you to
1526 debug basic ARM and THUMB instructions, and provides
1527 record/replay support.
1529 * The option "symbol-reloading" has been deleted as it is no longer used.
1533 ** GDB commands implemented in Python can now be put in command class
1536 ** The "maint set python print-stack on|off" is now deleted.
1538 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1539 apply "flag enum"-style pretty-printing to any enum.
1541 ** gdb.lookup_symbol can now work when there is no current frame.
1543 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1544 the source at which the symbol was defined.
1546 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1547 method 'value'. The former indicates whether the symbol needs a
1548 frame in order to compute its value, and the latter computes the
1551 ** A new method 'referenced_value' on gdb.Value objects which can
1552 dereference pointer as well as C++ reference values.
1554 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1555 which return the global and static blocks (as gdb.Block objects),
1556 of the underlying symbol table, respectively.
1558 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1559 object associated with a PC value.
1561 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1562 of the address range occupied by code for the current source line.
1564 * Go language support.
1565 GDB now supports debugging programs written in the Go programming
1568 * GDBserver now supports stdio connections.
1569 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1571 * The binary "gdbtui" can no longer be built or installed.
1572 Use "gdb -tui" instead.
1574 * GDB will now print "flag" enums specially. A flag enum is one where
1575 all the enumerator values have no bits in common when pairwise
1576 "and"ed. When printing a value whose type is a flag enum, GDB will
1577 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1578 (gdb) print (enum E) 3
1581 * The filename part of a linespec will now match trailing components
1582 of a source file name. For example, "break gcc/expr.c:1000" will
1583 now set a breakpoint in build/gcc/expr.c, but not
1584 build/libcpp/expr.c.
1586 * The "info proc" and "generate-core-file" commands will now also
1587 work on remote targets connected to GDBserver on Linux.
1589 * The command "info catch" has been removed. It has been disabled
1590 since December 2007.
1592 * The "catch exception" and "catch assert" commands now accept
1593 a condition at the end of the command, much like the "break"
1594 command does. For instance:
1596 (gdb) catch exception Constraint_Error if Barrier = True
1598 Previously, it was possible to add a condition to such catchpoints,
1599 but it had to be done as a second step, after the catchpoint had been
1600 created, using the "condition" command.
1602 * The "info static-tracepoint-marker" command will now also work on
1603 native Linux targets with in-process agent.
1605 * GDB can now set breakpoints on inlined functions.
1607 * The .gdb_index section has been updated to include symbols for
1608 inlined functions. GDB will ignore older .gdb_index sections by
1609 default, which could cause symbol files to be loaded more slowly
1610 until their .gdb_index sections can be recreated. The new command
1611 "set use-deprecated-index-sections on" will cause GDB to use any older
1612 .gdb_index sections it finds. This will restore performance, but the
1613 ability to set breakpoints on inlined functions will be lost in symbol
1614 files with older .gdb_index sections.
1616 The .gdb_index section has also been updated to record more information
1617 about each symbol. This speeds up the "info variables", "info functions"
1618 and "info types" commands when used with programs having the .gdb_index
1619 section, as well as speeding up debugging with shared libraries using
1620 the .gdb_index section.
1622 * Ada support for GDB/MI Variable Objects has been added.
1624 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1629 ** New command -info-os is the MI equivalent of "info os".
1631 ** Output logs ("set logging" and related) now include MI output.
1635 ** "set use-deprecated-index-sections on|off"
1636 "show use-deprecated-index-sections on|off"
1637 Controls the use of deprecated .gdb_index sections.
1639 ** "catch load" and "catch unload" can be used to stop when a shared
1640 library is loaded or unloaded, respectively.
1642 ** "enable count" can be used to auto-disable a breakpoint after
1645 ** "info vtbl" can be used to show the virtual method tables for
1646 C++ and Java objects.
1648 ** "explore" and its sub commands "explore value" and "explore type"
1649 can be used to recursively explore values and types of
1650 expressions. These commands are available only if GDB is
1651 configured with '--with-python'.
1653 ** "info auto-load" shows status of all kinds of auto-loaded files,
1654 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1655 sequences of commands files, "info auto-load python-scripts"
1656 shows status of auto-loading Python script files,
1657 "info auto-load local-gdbinit" shows status of loading init file
1658 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1659 status of inferior specific thread debugging shared library loading.
1661 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1662 and "show auto-load-scripts" commands have been deprecated, use their
1663 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1664 and "show auto-load python-scripts" counterparts instead.
1666 ** "dprintf location,format,args..." creates a dynamic printf, which
1667 is basically a breakpoint that does a printf and immediately
1668 resumes your program's execution, so it is like a printf that you
1669 can insert dynamically at runtime instead of at compiletime.
1671 ** "set print symbol"
1673 Controls whether GDB attempts to display the symbol, if any,
1674 corresponding to addresses it prints. This defaults to "on", but
1675 you can set it to "off" to restore GDB's previous behavior.
1677 * Deprecated commands
1679 ** For the Renesas Super-H architecture, the "regs" command has been
1680 deprecated, and "info all-registers" should be used instead.
1684 Renesas RL78 rl78-*-elf
1685 HP OpenVMS ia64 ia64-hp-openvms*
1687 * GDBserver supports evaluation of breakpoint conditions. When
1688 support is advertised by GDBserver, GDB may be told to send the
1689 breakpoint conditions in bytecode form to GDBserver. GDBserver
1690 will only report the breakpoint trigger to GDB when its condition
1695 set mips compression
1696 show mips compression
1697 Select the compressed ISA encoding used in functions that have no symbol
1698 information available. The encoding can be set to either of:
1701 and is updated automatically from ELF file flags if available.
1703 set breakpoint condition-evaluation
1704 show breakpoint condition-evaluation
1705 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1706 GDBserver ("target"). Default option "auto" chooses the most efficient
1708 This option can improve debugger efficiency depending on the speed of the
1712 Disable auto-loading globally.
1715 Show auto-loading setting of all kinds of auto-loaded files.
1717 set auto-load gdb-scripts on|off
1718 show auto-load gdb-scripts
1719 Control auto-loading of GDB canned sequences of commands files.
1721 set auto-load python-scripts on|off
1722 show auto-load python-scripts
1723 Control auto-loading of Python script files.
1725 set auto-load local-gdbinit on|off
1726 show auto-load local-gdbinit
1727 Control loading of init file (.gdbinit) from current directory.
1729 set auto-load libthread-db on|off
1730 show auto-load libthread-db
1731 Control auto-loading of inferior specific thread debugging shared library.
1733 set auto-load scripts-directory <dir1>[:<dir2>...]
1734 show auto-load scripts-directory
1735 Set a list of directories from which to load auto-loaded scripts.
1736 Automatically loaded Python scripts and GDB scripts are located in one
1737 of the directories listed by this option.
1738 The delimiter (':' above) may differ according to the host platform.
1740 set auto-load safe-path <dir1>[:<dir2>...]
1741 show auto-load safe-path
1742 Set a list of directories from which it is safe to auto-load files.
1743 The delimiter (':' above) may differ according to the host platform.
1745 set debug auto-load on|off
1746 show debug auto-load
1747 Control display of debugging info for auto-loading the files above.
1749 set dprintf-style gdb|call|agent
1751 Control the way in which a dynamic printf is performed; "gdb"
1752 requests a GDB printf command, while "call" causes dprintf to call a
1753 function in the inferior. "agent" requests that the target agent
1754 (such as GDBserver) do the printing.
1756 set dprintf-function <expr>
1757 show dprintf-function
1758 set dprintf-channel <expr>
1759 show dprintf-channel
1760 Set the function and optional first argument to the call when using
1761 the "call" style of dynamic printf.
1763 set disconnected-dprintf on|off
1764 show disconnected-dprintf
1765 Control whether agent-style dynamic printfs continue to be in effect
1766 after GDB disconnects.
1768 * New configure options
1770 --with-auto-load-dir
1771 Configure default value for the 'set auto-load scripts-directory'
1772 setting above. It defaults to '$debugdir:$datadir/auto-load',
1773 $debugdir representing global debugging info directories (available
1774 via 'show debug-file-directory') and $datadir representing GDB's data
1775 directory (available via 'show data-directory').
1777 --with-auto-load-safe-path
1778 Configure default value for the 'set auto-load safe-path' setting
1779 above. It defaults to the --with-auto-load-dir setting.
1781 --without-auto-load-safe-path
1782 Set 'set auto-load safe-path' to '/', effectively disabling this
1785 * New remote packets
1787 z0/z1 conditional breakpoints extension
1789 The z0/z1 breakpoint insertion packets have been extended to carry
1790 a list of conditional expressions over to the remote stub depending on the
1791 condition evaluation mode. The use of this extension can be controlled
1792 via the "set remote conditional-breakpoints-packet" command.
1796 Specify the signals which the remote stub may pass to the debugged
1797 program without GDB involvement.
1799 * New command line options
1801 --init-command=FILE, -ix Like --command, -x but execute it
1802 before loading inferior.
1803 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1804 execute it before loading inferior.
1806 *** Changes in GDB 7.4
1808 * GDB now handles ambiguous linespecs more consistently; the existing
1809 FILE:LINE support has been expanded to other types of linespecs. A
1810 breakpoint will now be set on all matching locations in all
1811 inferiors, and locations will be added or removed according to
1814 * GDB now allows you to skip uninteresting functions and files when
1815 stepping with the "skip function" and "skip file" commands.
1817 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1818 and "show remote hardware-watchpoint-length-limit". These allows to
1819 set or show the maximum length limit (in bytes) of a remote
1820 target hardware watchpoint.
1822 This allows e.g. to use "unlimited" hardware watchpoints with the
1823 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1824 watchpoints are slower than real hardware watchpoints but are
1825 significantly faster than gdb software watchpoints.
1829 ** The register_pretty_printer function in module gdb.printing now takes
1830 an optional `replace' argument. If True, the new printer replaces any
1833 ** The "maint set python print-stack on|off" command has been
1834 deprecated and will be deleted in GDB 7.5.
1835 A new command: "set python print-stack none|full|message" has
1836 replaced it. Additionally, the default for "print-stack" is
1837 now "message", which just prints the error message without
1840 ** A prompt substitution hook (prompt_hook) is now available to the
1843 ** A new Python module, gdb.prompt has been added to the GDB Python
1844 modules library. This module provides functionality for
1845 escape sequences in prompts (used by set/show
1846 extended-prompt). These escape sequences are replaced by their
1847 corresponding value.
1849 ** Python commands and convenience-functions located in
1850 'data-directory'/python/gdb/command and
1851 'data-directory'/python/gdb/function are now automatically loaded
1854 ** Blocks now provide four new attributes. global_block and
1855 static_block will return the global and static blocks
1856 respectively. is_static and is_global are boolean attributes
1857 that indicate if the block is one of those two types.
1859 ** Symbols now provide the "type" attribute, the type of the symbol.
1861 ** The "gdb.breakpoint" function has been deprecated in favor of
1864 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1865 of a function. This class is based on the "finish" command
1866 available in the CLI.
1868 ** Type objects for struct and union types now allow access to
1869 the fields using standard Python dictionary (mapping) methods.
1870 For example, "some_type['myfield']" now works, as does
1871 "some_type.items()".
1873 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1876 ** A new function, "deep_items" has been added to the gdb.types
1877 module in the GDB Python modules library. This function returns
1878 an iterator over the fields of a struct or union type. Unlike
1879 the standard Python "iteritems" method, it will recursively traverse
1880 any anonymous fields.
1884 ** "*stopped" events can report several new "reason"s, such as
1887 ** Breakpoint changes are now notified using new async records, like
1888 "=breakpoint-modified".
1890 ** New command -ada-task-info.
1892 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1893 $sdir specifies the default system locations of shared libraries.
1894 $pdir specifies the directory where the libpthread used by the application
1897 GDB no longer looks in $sdir and $pdir after it has searched the directories
1898 mentioned in libthread-db-search-path. If you want to search those
1899 directories, they must be specified in libthread-db-search-path.
1900 The default value of libthread-db-search-path on GNU/Linux and Solaris
1901 systems is now "$sdir:$pdir".
1903 $pdir is not supported by gdbserver, it is currently ignored.
1904 $sdir is supported by gdbserver.
1906 * New configure option --with-iconv-bin.
1907 When using the internationalization support like the one in the GNU C
1908 library, GDB will invoke the "iconv" program to get a list of supported
1909 character sets. If this program lives in a non-standard location, one can
1910 use this option to specify where to find it.
1912 * When natively debugging programs on PowerPC BookE processors running
1913 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1914 watchpoints, which specify a mask in addition to an address to watch.
1915 The mask specifies that some bits of an address (the bits which are
1916 reset in the mask) should be ignored when matching the address accessed
1917 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1918 section in the user manual for more details.
1920 * The new option --once causes GDBserver to stop listening for connections once
1921 the first connection is made. The listening port used by GDBserver will
1922 become available after that.
1924 * New commands "info macros" and "alias" have been added.
1926 * New function parameters suffix @entry specifies value of function parameter
1927 at the time the function got called. Entry values are available only since
1933 "!" is now an alias of the "shell" command.
1934 Note that no space is needed between "!" and SHELL COMMAND.
1938 watch EXPRESSION mask MASK_VALUE
1939 The watch command now supports the mask argument which allows creation
1940 of masked watchpoints, if the current architecture supports this feature.
1942 info auto-load-scripts [REGEXP]
1943 This command was formerly named "maintenance print section-scripts".
1944 It is now generally useful and is no longer a maintenance-only command.
1946 info macro [-all] [--] MACRO
1947 The info macro command has new options `-all' and `--'. The first for
1948 printing all definitions of a macro. The second for explicitly specifying
1949 the end of arguments and the beginning of the macro name in case the macro
1950 name starts with a hyphen.
1952 collect[/s] EXPRESSIONS
1953 The tracepoint collect command now takes an optional modifier "/s"
1954 that directs it to dereference pointer-to-character types and
1955 collect the bytes of memory up to a zero byte. The behavior is
1956 similar to what you see when you use the regular print command on a
1957 string. An optional integer following the "/s" sets a bound on the
1958 number of bytes that will be collected.
1961 The trace start command now interprets any supplied arguments as a
1962 note to be recorded with the trace run, with an effect similar to
1963 setting the variable trace-notes.
1966 The trace stop command now interprets any arguments as a note to be
1967 mentioned along with the tstatus report that the trace was stopped
1968 with a command. The effect is similar to setting the variable
1971 * Tracepoints can now be enabled and disabled at any time after a trace
1972 experiment has been started using the standard "enable" and "disable"
1973 commands. It is now possible to start a trace experiment with no enabled
1974 tracepoints; GDB will display a warning, but will allow the experiment to
1975 begin, assuming that tracepoints will be enabled as needed while the trace
1978 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1979 locations with 4-byte instructions, when they were previously
1980 limited to locations with instructions of 5 bytes or longer.
1984 set debug dwarf2-read
1985 show debug dwarf2-read
1986 Turns on or off display of debugging messages related to reading
1987 DWARF debug info. The default is off.
1989 set debug symtab-create
1990 show debug symtab-create
1991 Turns on or off display of debugging messages related to symbol table
1992 creation. The default is off.
1995 show extended-prompt
1996 Set the GDB prompt, and allow escape sequences to be inserted to
1997 display miscellaneous information (see 'help set extended-prompt'
1998 for the list of sequences). This prompt (and any information
1999 accessed through the escape sequences) is updated every time the
2000 prompt is displayed.
2002 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2003 show print entry-values
2004 Set printing of frame argument values at function entry. In some cases
2005 GDB can determine the value of function argument which was passed by the
2006 function caller, even if the value was modified inside the called function.
2008 set debug entry-values
2009 show debug entry-values
2010 Control display of debugging info for determining frame argument values at
2011 function entry and virtual tail call frames.
2013 set basenames-may-differ
2014 show basenames-may-differ
2015 Set whether a source file may have multiple base names.
2016 (A "base name" is the name of a file with the directory part removed.
2017 Example: The base name of "/home/user/hello.c" is "hello.c".)
2018 If set, GDB will canonicalize file names (e.g., expand symlinks)
2019 before comparing them. Canonicalization is an expensive operation,
2020 but it allows the same file be known by more than one base name.
2021 If not set (the default), all source files are assumed to have just
2022 one base name, and gdb will do file name comparisons more efficiently.
2028 Set a user name and notes for the current and any future trace runs.
2029 This is useful for long-running and/or disconnected traces, to
2030 inform others (or yourself) as to who is running the trace, supply
2031 contact information, or otherwise explain what is going on.
2033 set trace-stop-notes
2034 show trace-stop-notes
2035 Set a note attached to the trace run, that is displayed when the
2036 trace has been stopped by a tstop command. This is useful for
2037 instance as an explanation, if you are stopping a trace run that was
2038 started by someone else.
2040 * New remote packets
2044 Dynamically enable a tracepoint in a started trace experiment.
2048 Dynamically disable a tracepoint in a started trace experiment.
2052 Set the user and notes of the trace run.
2056 Query the current status of a tracepoint.
2060 Query the minimum length of instruction at which a fast tracepoint may
2063 * Dcache size (number of lines) and line-size are now runtime-configurable
2064 via "set dcache line" and "set dcache line-size" commands.
2068 Texas Instruments TMS320C6x tic6x-*-*
2072 Renesas RL78 rl78-*-elf
2074 *** Changes in GDB 7.3.1
2076 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2078 *** Changes in GDB 7.3
2080 * GDB has a new command: "thread find [REGEXP]".
2081 It finds the thread id whose name, target id, or thread extra info
2082 matches the given regular expression.
2084 * The "catch syscall" command now works on mips*-linux* targets.
2086 * The -data-disassemble MI command now supports modes 2 and 3 for
2087 dumping the instruction opcodes.
2089 * New command line options
2091 -data-directory DIR Specify DIR as the "data-directory".
2092 This is mostly for testing purposes.
2094 * The "maint set python auto-load on|off" command has been renamed to
2095 "set auto-load-scripts on|off".
2097 * GDB has a new command: "set directories".
2098 It is like the "dir" command except that it replaces the
2099 source path list instead of augmenting it.
2101 * GDB now understands thread names.
2103 On GNU/Linux, "info threads" will display the thread name as set by
2104 prctl or pthread_setname_np.
2106 There is also a new command, "thread name", which can be used to
2107 assign a name internally for GDB to display.
2110 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2111 has been integrated into GDB.
2115 ** The function gdb.Write now accepts an optional keyword 'stream'.
2116 This keyword, when provided, will direct the output to either
2117 stdout, stderr, or GDB's logging output.
2119 ** Parameters can now be be sub-classed in Python, and in particular
2120 you may implement the get_set_doc and get_show_doc functions.
2121 This improves how Parameter set/show documentation is processed
2122 and allows for more dynamic content.
2124 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2125 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2126 have an is_valid method.
2128 ** Breakpoints can now be sub-classed in Python, and in particular
2129 you may implement a 'stop' function that is executed each time
2130 the inferior reaches that breakpoint.
2132 ** New function gdb.lookup_global_symbol looks up a global symbol.
2134 ** GDB values in Python are now callable if the value represents a
2135 function. For example, if 'some_value' represents a function that
2136 takes two integer parameters and returns a value, you can call
2137 that function like so:
2139 result = some_value (10,20)
2141 ** Module gdb.types has been added.
2142 It contains a collection of utilities for working with gdb.Types objects:
2143 get_basic_type, has_field, make_enum_dict.
2145 ** Module gdb.printing has been added.
2146 It contains utilities for writing and registering pretty-printers.
2147 New classes: PrettyPrinter, SubPrettyPrinter,
2148 RegexpCollectionPrettyPrinter.
2149 New function: register_pretty_printer.
2151 ** New commands "info pretty-printers", "enable pretty-printer" and
2152 "disable pretty-printer" have been added.
2154 ** gdb.parameter("directories") is now available.
2156 ** New function gdb.newest_frame returns the newest frame in the
2159 ** The gdb.InferiorThread class has a new "name" attribute. This
2160 holds the thread's name.
2162 ** Python Support for Inferior events.
2163 Python scripts can add observers to be notified of events
2164 occurring in the process being debugged.
2165 The following events are currently supported:
2166 - gdb.events.cont Continue event.
2167 - gdb.events.exited Inferior exited event.
2168 - gdb.events.stop Signal received, and Breakpoint hit events.
2172 ** GDB now puts template parameters in scope when debugging in an
2173 instantiation. For example, if you have:
2175 template<int X> int func (void) { return X; }
2177 then if you step into func<5>, "print X" will show "5". This
2178 feature requires proper debuginfo support from the compiler; it
2179 was added to GCC 4.5.
2181 ** The motion commands "next", "finish", "until", and "advance" now
2182 work better when exceptions are thrown. In particular, GDB will
2183 no longer lose control of the inferior; instead, the GDB will
2184 stop the inferior at the point at which the exception is caught.
2185 This functionality requires a change in the exception handling
2186 code that was introduced in GCC 4.5.
2188 * GDB now follows GCC's rules on accessing volatile objects when
2189 reading or writing target state during expression evaluation.
2190 One notable difference to prior behavior is that "print x = 0"
2191 no longer generates a read of x; the value of the assignment is
2192 now always taken directly from the value being assigned.
2194 * GDB now has some support for using labels in the program's source in
2195 linespecs. For instance, you can use "advance label" to continue
2196 execution to a label.
2198 * GDB now has support for reading and writing a new .gdb_index
2199 section. This section holds a fast index of DWARF debugging
2200 information and can be used to greatly speed up GDB startup and
2201 operation. See the documentation for `save gdb-index' for details.
2203 * The "watch" command now accepts an optional "-location" argument.
2204 When used, this causes GDB to watch the memory referred to by the
2205 expression. Such a watchpoint is never deleted due to it going out
2208 * GDB now supports thread debugging of core dumps on GNU/Linux.
2210 GDB now activates thread debugging using the libthread_db library
2211 when debugging GNU/Linux core dumps, similarly to when debugging
2212 live processes. As a result, when debugging a core dump file, GDB
2213 is now able to display pthread_t ids of threads. For example, "info
2214 threads" shows the same output as when debugging the process when it
2215 was live. In earlier releases, you'd see something like this:
2218 * 1 LWP 6780 main () at main.c:10
2220 While now you see this:
2223 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2225 It is also now possible to inspect TLS variables when debugging core
2228 When debugging a core dump generated on a machine other than the one
2229 used to run GDB, you may need to point GDB at the correct
2230 libthread_db library with the "set libthread-db-search-path"
2231 command. See the user manual for more details on this command.
2233 * When natively debugging programs on PowerPC BookE processors running
2234 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2235 which stop execution of the inferior whenever it executes an instruction
2236 at any address within the specified range. See the "PowerPC Embedded"
2237 section in the user manual for more details.
2239 * New features in the GDB remote stub, GDBserver
2241 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2242 and i686 LynxOS (version 5.x).
2244 ** GDBserver is now supported on Blackfin Linux.
2246 * New native configurations
2248 ia64 HP-UX ia64-*-hpux*
2252 Analog Devices, Inc. Blackfin Processor bfin-*
2254 * Ada task switching is now supported on sparc-elf targets when
2255 debugging a program using the Ravenscar Profile. For more information,
2256 see the "Tasking Support when using the Ravenscar Profile" section
2257 in the GDB user manual.
2259 * Guile support was removed.
2261 * New features in the GNU simulator
2263 ** The --map-info flag lists all known core mappings.
2265 ** CFI flashes may be simulated via the "cfi" device.
2267 *** Changes in GDB 7.2
2269 * Shared library support for remote targets by default
2271 When GDB is configured for a generic, non-OS specific target, like
2272 for example, --target=arm-eabi or one of the many *-*-elf targets,
2273 GDB now queries remote stubs for loaded shared libraries using the
2274 `qXfer:libraries:read' packet. Previously, shared library support
2275 was always disabled for such configurations.
2279 ** Argument Dependent Lookup (ADL)
2281 In C++ ADL lookup directs function search to the namespaces of its
2282 arguments even if the namespace has not been imported.
2292 Here the compiler will search for `foo' in the namespace of 'b'
2293 and find A::foo. GDB now supports this. This construct is commonly
2294 used in the Standard Template Library for operators.
2296 ** Improved User Defined Operator Support
2298 In addition to member operators, GDB now supports lookup of operators
2299 defined in a namespace and imported with a `using' directive, operators
2300 defined in the global scope, operators imported implicitly from an
2301 anonymous namespace, and the ADL operators mentioned in the previous
2303 GDB now also supports proper overload resolution for all the previously
2304 mentioned flavors of operators.
2306 ** static const class members
2308 Printing of static const class members that are initialized in the
2309 class definition has been fixed.
2311 * Windows Thread Information Block access.
2313 On Windows targets, GDB now supports displaying the Windows Thread
2314 Information Block (TIB) structure. This structure is visible either
2315 by using the new command `info w32 thread-information-block' or, by
2316 dereferencing the new convenience variable named `$_tlb', a
2317 thread-specific pointer to the TIB. This feature is also supported
2318 when remote debugging using GDBserver.
2320 * Static tracepoints
2322 Static tracepoints are calls in the user program into a tracing
2323 library. One such library is a port of the LTTng kernel tracer to
2324 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2325 When debugging with GDBserver, GDB now supports combining the GDB
2326 tracepoint machinery with such libraries. For example: the user can
2327 use GDB to probe a static tracepoint marker (a call from the user
2328 program into the tracing library) with the new "strace" command (see
2329 "New commands" below). This creates a "static tracepoint" in the
2330 breakpoint list, that can be manipulated with the same feature set
2331 as fast and regular tracepoints. E.g., collect registers, local and
2332 global variables, collect trace state variables, and define
2333 tracepoint conditions. In addition, the user can collect extra
2334 static tracepoint marker specific data, by collecting the new
2335 $_sdata internal variable. When analyzing the trace buffer, you can
2336 inspect $_sdata like any other variable available to GDB. For more
2337 information, see the "Tracepoints" chapter in GDB user manual. New
2338 remote packets have been defined to support static tracepoints, see
2339 the "New remote packets" section below.
2341 * Better reconstruction of tracepoints after disconnected tracing
2343 GDB will attempt to download the original source form of tracepoint
2344 definitions when starting a trace run, and then will upload these
2345 upon reconnection to the target, resulting in a more accurate
2346 reconstruction of the tracepoints that are in use on the target.
2350 You can now exercise direct control over the ways that GDB can
2351 affect your program. For instance, you can disallow the setting of
2352 breakpoints, so that the program can run continuously (assuming
2353 non-stop mode). In addition, the "observer" variable is available
2354 to switch all of the different controls; in observer mode, GDB
2355 cannot affect the target's behavior at all, which is useful for
2356 tasks like diagnosing live systems in the field.
2358 * The new convenience variable $_thread holds the number of the
2361 * New remote packets
2365 Return the address of the Windows Thread Information Block of a given thread.
2369 In response to several of the tracepoint packets, the target may now
2370 also respond with a number of intermediate `qRelocInsn' request
2371 packets before the final result packet, to have GDB handle
2372 relocating an instruction to execute at a different address. This
2373 is particularly useful for stubs that support fast tracepoints. GDB
2374 reports support for this feature in the qSupported packet.
2378 List static tracepoint markers in the target program.
2382 List static tracepoint markers at a given address in the target
2385 qXfer:statictrace:read
2387 Read the static trace data collected (by a `collect $_sdata'
2388 tracepoint action). The remote stub reports support for this packet
2389 to gdb's qSupported query.
2393 Send the current settings of GDB's permission flags.
2397 Send part of the source (textual) form of a tracepoint definition,
2398 which includes location, conditional, and action list.
2400 * The source command now accepts a -s option to force searching for the
2401 script in the source search path even if the script name specifies
2404 * New features in the GDB remote stub, GDBserver
2406 - GDBserver now support tracepoints (including fast tracepoints, and
2407 static tracepoints). The feature is currently supported by the
2408 i386-linux and amd64-linux builds. See the "Tracepoints support
2409 in gdbserver" section in the manual for more information.
2411 GDBserver JIT compiles the tracepoint's conditional agent
2412 expression bytecode into native code whenever possible for low
2413 overhead dynamic tracepoints conditionals. For such tracepoints,
2414 an expression that examines program state is evaluated when the
2415 tracepoint is reached, in order to determine whether to capture
2416 trace data. If the condition is simple and false, processing the
2417 tracepoint finishes very quickly and no data is gathered.
2419 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2420 for static tracepoints support.
2422 - GDBserver now supports x86_64 Windows 64-bit debugging.
2424 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2425 it understands register description.
2427 * The --batch flag now disables pagination and queries.
2429 * X86 general purpose registers
2431 GDB now supports reading/writing byte, word and double-word x86
2432 general purpose registers directly. This means you can use, say,
2433 $ah or $ax to refer, respectively, to the byte register AH and
2434 16-bit word register AX that are actually portions of the 32-bit
2435 register EAX or 64-bit register RAX.
2437 * The `commands' command now accepts a range of breakpoints to modify.
2438 A plain `commands' following a command that creates multiple
2439 breakpoints affects all the breakpoints set by that command. This
2440 applies to breakpoints set by `rbreak', and also applies when a
2441 single `break' command creates multiple breakpoints (e.g.,
2442 breakpoints on overloaded c++ functions).
2444 * The `rbreak' command now accepts a filename specification as part of
2445 its argument, limiting the functions selected by the regex to those
2446 in the specified file.
2448 * Support for remote debugging Windows and SymbianOS shared libraries
2449 from Unix hosts has been improved. Non Windows GDB builds now can
2450 understand target reported file names that follow MS-DOS based file
2451 system semantics, such as file names that include drive letters and
2452 use the backslash character as directory separator. This makes it
2453 possible to transparently use the "set sysroot" and "set
2454 solib-search-path" on Unix hosts to point as host copies of the
2455 target's shared libraries. See the new command "set
2456 target-file-system-kind" described below, and the "Commands to
2457 specify files" section in the user manual for more information.
2461 eval template, expressions...
2462 Convert the values of one or more expressions under the control
2463 of the string template to a command line, and call it.
2465 set target-file-system-kind unix|dos-based|auto
2466 show target-file-system-kind
2467 Set or show the assumed file system kind for target reported file
2470 save breakpoints <filename>
2471 Save all current breakpoint definitions to a file suitable for use
2472 in a later debugging session. To read the saved breakpoint
2473 definitions, use the `source' command.
2475 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2478 info static-tracepoint-markers
2479 Display information about static tracepoint markers in the target.
2481 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2482 Define a static tracepoint by probing a marker at the given
2483 function, line, address, or marker ID.
2487 Enable and disable observer mode.
2489 set may-write-registers on|off
2490 set may-write-memory on|off
2491 set may-insert-breakpoints on|off
2492 set may-insert-tracepoints on|off
2493 set may-insert-fast-tracepoints on|off
2494 set may-interrupt on|off
2495 Set individual permissions for GDB effects on the target. Note that
2496 some of these settings can have undesirable or surprising
2497 consequences, particularly when changed in the middle of a session.
2498 For instance, disabling the writing of memory can prevent
2499 breakpoints from being inserted, cause single-stepping to fail, or
2500 even crash your program, if you disable after breakpoints have been
2501 inserted. However, GDB should not crash.
2503 set record memory-query on|off
2504 show record memory-query
2505 Control whether to stop the inferior if memory changes caused
2506 by an instruction cannot be recorded.
2511 The disassemble command now supports "start,+length" form of two arguments.
2515 ** GDB now provides a new directory location, called the python directory,
2516 where Python scripts written for GDB can be installed. The location
2517 of that directory is <data-directory>/python, where <data-directory>
2518 is the GDB data directory. For more details, see section `Scripting
2519 GDB using Python' in the manual.
2521 ** The GDB Python API now has access to breakpoints, symbols, symbol
2522 tables, program spaces, inferiors, threads and frame's code blocks.
2523 Additionally, GDB Parameters can now be created from the API, and
2524 manipulated via set/show in the CLI.
2526 ** New functions gdb.target_charset, gdb.target_wide_charset,
2527 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2529 ** New exception gdb.GdbError.
2531 ** Pretty-printers are now also looked up in the current program space.
2533 ** Pretty-printers can now be individually enabled and disabled.
2535 ** GDB now looks for names of Python scripts to auto-load in a
2536 special section named `.debug_gdb_scripts', in addition to looking
2537 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2539 * Tracepoint actions were unified with breakpoint commands. In particular,
2540 there are no longer differences in "info break" output for breakpoints and
2541 tracepoints and the "commands" command can be used for both tracepoints and
2542 regular breakpoints.
2546 ARM Symbian arm*-*-symbianelf*
2548 * D language support.
2549 GDB now supports debugging programs written in the D programming
2552 * GDB now supports the extended ptrace interface for PowerPC which is
2553 available since Linux kernel version 2.6.34. This automatically enables
2554 any hardware breakpoints and additional hardware watchpoints available in
2555 the processor. The old ptrace interface exposes just one hardware
2556 watchpoint and no hardware breakpoints.
2558 * GDB is now able to use the Data Value Compare (DVC) register available on
2559 embedded PowerPC processors to implement in hardware simple watchpoint
2560 conditions of the form:
2562 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2564 This works in native GDB running on Linux kernels with the extended ptrace
2565 interface mentioned above.
2567 *** Changes in GDB 7.1
2571 ** Namespace Support
2573 GDB now supports importing of namespaces in C++. This enables the
2574 user to inspect variables from imported namespaces. Support for
2575 namepace aliasing has also been added. So, if a namespace is
2576 aliased in the current scope (e.g. namepace C=A; ) the user can
2577 print variables using the alias (e.g. (gdb) print C::x).
2581 All known bugs relating to the printing of virtual base class were
2582 fixed. It is now possible to call overloaded static methods using a
2587 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2588 and reinterpret_cast<> are now handled by the C++ expression parser.
2592 Xilinx MicroBlaze microblaze-*-*
2597 Xilinx MicroBlaze microblaze
2600 * Multi-program debugging.
2602 GDB now has support for multi-program (a.k.a. multi-executable or
2603 multi-exec) debugging. This allows for debugging multiple inferiors
2604 simultaneously each running a different program under the same GDB
2605 session. See "Debugging Multiple Inferiors and Programs" in the
2606 manual for more information. This implied some user visible changes
2607 in the multi-inferior support. For example, "info inferiors" now
2608 lists inferiors that are not running yet or that have exited
2609 already. See also "New commands" and "New options" below.
2611 * New tracing features
2613 GDB's tracepoint facility now includes several new features:
2615 ** Trace state variables
2617 GDB tracepoints now include support for trace state variables, which
2618 are variables managed by the target agent during a tracing
2619 experiment. They are useful for tracepoints that trigger each
2620 other, so for instance one tracepoint can count hits in a variable,
2621 and then a second tracepoint has a condition that is true when the
2622 count reaches a particular value. Trace state variables share the
2623 $-syntax of GDB convenience variables, and can appear in both
2624 tracepoint actions and condition expressions. Use the "tvariable"
2625 command to create, and "info tvariables" to view; see "Trace State
2626 Variables" in the manual for more detail.
2630 GDB now includes an option for defining fast tracepoints, which
2631 targets may implement more efficiently, such as by installing a jump
2632 into the target agent rather than a trap instruction. The resulting
2633 speedup can be by two orders of magnitude or more, although the
2634 tradeoff is that some program locations on some target architectures
2635 might not allow fast tracepoint installation, for instance if the
2636 instruction to be replaced is shorter than the jump. To request a
2637 fast tracepoint, use the "ftrace" command, with syntax identical to
2638 the regular trace command.
2640 ** Disconnected tracing
2642 It is now possible to detach GDB from the target while it is running
2643 a trace experiment, then reconnect later to see how the experiment
2644 is going. In addition, a new variable disconnected-tracing lets you
2645 tell the target agent whether to continue running a trace if the
2646 connection is lost unexpectedly.
2650 GDB now has the ability to save the trace buffer into a file, and
2651 then use that file as a target, similarly to you can do with
2652 corefiles. You can select trace frames, print data that was
2653 collected in them, and use tstatus to display the state of the
2654 tracing run at the moment that it was saved. To create a trace
2655 file, use "tsave <filename>", and to use it, do "target tfile
2658 ** Circular trace buffer
2660 You can ask the target agent to handle the trace buffer as a
2661 circular buffer, discarding the oldest trace frames to make room for
2662 newer ones, by setting circular-trace-buffer to on. This feature may
2663 not be available for all target agents.
2668 The disassemble command, when invoked with two arguments, now requires
2669 the arguments to be comma-separated.
2672 The info variables command now displays variable definitions. Files
2673 which only declare a variable are not shown.
2676 The source command is now capable of sourcing Python scripts.
2677 This feature is dependent on the debugger being build with Python
2680 Related to this enhancement is also the introduction of a new command
2681 "set script-extension" (see below).
2683 * New commands (for set/show, see "New options" below)
2685 record save [<FILENAME>]
2686 Save a file (in core file format) containing the process record
2687 execution log for replay debugging at a later time.
2689 record restore <FILENAME>
2690 Restore the process record execution log that was saved at an
2691 earlier time, for replay debugging.
2693 add-inferior [-copies <N>] [-exec <FILENAME>]
2696 clone-inferior [-copies <N>] [ID]
2697 Make a new inferior ready to execute the same program another
2698 inferior has loaded.
2703 maint info program-spaces
2704 List the program spaces loaded into GDB.
2706 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2707 show remote interrupt-sequence
2708 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2709 as the sequence to the remote target in order to interrupt the execution.
2710 Ctrl-C is a default. Some system prefers BREAK which is high level of
2711 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2712 Magic SysRq g. It is BREAK signal and character 'g'.
2714 set remote interrupt-on-connect [on | off]
2715 show remote interrupt-on-connect
2716 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2717 remote target when gdb connects to it. This is needed when you debug
2720 set remotebreak [on | off]
2722 Deprecated. Use "set/show remote interrupt-sequence" instead.
2724 tvariable $NAME [ = EXP ]
2725 Create or modify a trace state variable.
2728 List trace state variables and their values.
2730 delete tvariable $NAME ...
2731 Delete one or more trace state variables.
2734 Evaluate the given expressions without collecting anything into the
2735 trace buffer. (Valid in tracepoint actions only.)
2737 ftrace FN / FILE:LINE / *ADDR
2738 Define a fast tracepoint at the given function, line, or address.
2740 * New expression syntax
2742 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2743 GDB now parses 0b101010 identically with 42.
2747 set follow-exec-mode new|same
2748 show follow-exec-mode
2749 Control whether GDB reuses the same inferior across an exec call or
2750 creates a new one. This is useful to be able to restart the old
2751 executable after the inferior having done an exec call.
2753 set default-collect EXPR, ...
2754 show default-collect
2755 Define a list of expressions to be collected at each tracepoint.
2756 This is a useful way to ensure essential items are not overlooked,
2757 such as registers or a critical global variable.
2759 set disconnected-tracing
2760 show disconnected-tracing
2761 If set to 1, the target is instructed to continue tracing if it
2762 loses its connection to GDB. If 0, the target is to stop tracing
2765 set circular-trace-buffer
2766 show circular-trace-buffer
2767 If set to on, the target is instructed to use a circular trace buffer
2768 and discard the oldest trace frames instead of stopping the trace due
2769 to a full trace buffer. If set to off, the trace stops when the buffer
2770 fills up. Some targets may not support this.
2772 set script-extension off|soft|strict
2773 show script-extension
2774 If set to "off", the debugger does not perform any script language
2775 recognition, and all sourced files are assumed to be GDB scripts.
2776 If set to "soft" (the default), files are sourced according to
2777 filename extension, falling back to GDB scripts if the first
2779 If set to "strict", files are sourced according to filename extension.
2781 set ada trust-PAD-over-XVS on|off
2782 show ada trust-PAD-over-XVS
2783 If off, activate a workaround against a bug in the debugging information
2784 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2785 the GCC sources for more information about the GNAT encoding and
2786 PAD types in particular). It is always safe to set this option to
2787 off, but this introduces a slight performance penalty. The default
2790 * Python API Improvements
2792 ** GDB provides the new class gdb.LazyString. This is useful in
2793 some pretty-printing cases. The new method gdb.Value.lazy_string
2794 provides a simple way to create objects of this type.
2796 ** The fields returned by gdb.Type.fields now have an
2797 `is_base_class' attribute.
2799 ** The new method gdb.Type.range returns the range of an array type.
2801 ** The new method gdb.parse_and_eval can be used to parse and
2802 evaluate an expression.
2804 * New remote packets
2807 Define a trace state variable.
2810 Get the current value of a trace state variable.
2813 Set desired tracing behavior upon disconnection.
2816 Set the trace buffer to be linear or circular.
2819 Get data about the tracepoints currently in use.
2823 Process record now works correctly with hardware watchpoints.
2825 Multiple bug fixes have been made to the mips-irix port, making it
2826 much more reliable. In particular:
2827 - Debugging threaded applications is now possible again. Previously,
2828 GDB would hang while starting the program, or while waiting for
2829 the program to stop at a breakpoint.
2830 - Attaching to a running process no longer hangs.
2831 - An error occurring while loading a core file has been fixed.
2832 - Changing the value of the PC register now works again. This fixes
2833 problems observed when using the "jump" command, or when calling
2834 a function from GDB, or even when assigning a new value to $pc.
2835 - With the "finish" and "return" commands, the return value for functions
2836 returning a small array is now correctly printed.
2837 - It is now possible to break on shared library code which gets executed
2838 during a shared library init phase (code executed while executing
2839 their .init section). Previously, the breakpoint would have no effect.
2840 - GDB is now able to backtrace through the signal handler for
2841 non-threaded programs.
2843 PIE (Position Independent Executable) programs debugging is now supported.
2844 This includes debugging execution of PIC (Position Independent Code) shared
2845 libraries although for that, it should be possible to run such libraries as an
2848 *** Changes in GDB 7.0
2850 * GDB now has an interface for JIT compilation. Applications that
2851 dynamically generate code can create symbol files in memory and register
2852 them with GDB. For users, the feature should work transparently, and
2853 for JIT developers, the interface is documented in the GDB manual in the
2854 "JIT Compilation Interface" chapter.
2856 * Tracepoints may now be conditional. The syntax is as for
2857 breakpoints; either an "if" clause appended to the "trace" command,
2858 or the "condition" command is available. GDB sends the condition to
2859 the target for evaluation using the same bytecode format as is used
2860 for tracepoint actions.
2862 * The disassemble command now supports: an optional /r modifier, print the
2863 raw instructions in hex as well as in symbolic form, and an optional /m
2864 modifier to print mixed source+assembly.
2866 * Process record and replay
2868 In a architecture environment that supports ``process record and
2869 replay'', ``process record and replay'' target can record a log of
2870 the process execution, and replay it with both forward and reverse
2873 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2874 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2875 set execution-direction {forward|reverse}, for targets that support
2878 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2879 feature is available with a native GDB running on kernel version
2882 * GDB now has support for multi-byte and wide character sets on the
2883 target. Strings whose character type is wchar_t, char16_t, or
2884 char32_t are now correctly printed. GDB supports wide- and unicode-
2885 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2886 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2887 `printf'. This feature requires iconv to work properly; if your
2888 system does not have a working iconv, GDB can use GNU libiconv. See
2889 the installation instructions for more information.
2891 * GDB now supports automatic retrieval of shared library files from
2892 remote targets. To use this feature, specify a system root that begins
2893 with the `remote:' prefix, either via the `set sysroot' command or via
2894 the `--with-sysroot' configure-time option.
2896 * "info sharedlibrary" now takes an optional regex of libraries to show,
2897 and it now reports if a shared library has no debugging information.
2899 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2900 now complete on file names.
2902 * When completing in expressions, gdb will attempt to limit
2903 completions to allowable structure or union fields, where appropriate.
2904 For instance, consider:
2906 # struct example { int f1; double f2; };
2907 # struct example variable;
2910 If the user types TAB at the end of this command line, the available
2911 completions will be "f1" and "f2".
2913 * Inlined functions are now supported. They show up in backtraces, and
2914 the "step", "next", and "finish" commands handle them automatically.
2916 * GDB now supports the token-splicing (##) and stringification (#)
2917 operators when expanding macros. It also supports variable-arity
2920 * GDB now supports inspecting extra signal information, exported by
2921 the new $_siginfo convenience variable. The feature is currently
2922 implemented on linux ARM, i386 and amd64.
2924 * GDB can now display the VFP floating point registers and NEON vector
2925 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2926 can provide these registers (requires Linux 2.6.30 or later). Remote
2927 and simulator targets may also provide them.
2929 * New remote packets
2932 Search memory for a sequence of bytes.
2935 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2936 operation over reliable transport links. Use of this packet is
2937 controlled by the `set remote noack-packet' command.
2940 Kill the process with the specified process ID. Use this in preference
2941 to `k' when multiprocess protocol extensions are supported.
2944 Obtains additional operating system information
2948 Read or write additional signal information.
2950 * Removed remote protocol undocumented extension
2952 An undocumented extension to the remote protocol's `S' stop reply
2953 packet that permited the stub to pass a process id was removed.
2954 Remote servers should use the `T' stop reply packet instead.
2956 * GDB now supports multiple function calling conventions according to the
2957 DWARF-2 DW_AT_calling_convention function attribute.
2959 * The SH target utilizes the aforementioned change to distinguish between gcc
2960 and Renesas calling convention. It also adds the new CLI commands
2961 `set/show sh calling-convention'.
2963 * GDB can now read compressed debug sections, as produced by GNU gold
2964 with the --compress-debug-sections=zlib flag.
2966 * 64-bit core files are now supported on AIX.
2968 * Thread switching is now supported on Tru64.
2970 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2971 which will be allocated using malloc later in program execution.
2973 * The qXfer:libraries:read remote procotol packet now allows passing a
2974 list of section offsets.
2976 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2977 conditions handling signals delivered during attach or thread creation
2978 have also been fixed.
2980 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2981 From the user's standpoint, all unqualified instances of True and False
2982 are treated as the standard definitions, regardless of context.
2984 * GDB now parses C++ symbol and type names more flexibly. For
2987 template<typename T> class C { };
2990 GDB will now correctly handle all of:
2992 ptype C<char const *>
2993 ptype C<char const*>
2994 ptype C<const char *>
2995 ptype C<const char*>
2997 * New features in the GDB remote stub, gdbserver
2999 - The "--wrapper" command-line argument tells gdbserver to use a
3000 wrapper program to launch programs for debugging.
3002 - On PowerPC and S/390 targets, it is now possible to use a single
3003 gdbserver executable to debug both 32-bit and 64-bit programs.
3004 (This requires gdbserver itself to be built as a 64-bit executable.)
3006 - gdbserver uses the new noack protocol mode for TCP connections to
3007 reduce communications latency, if also supported and enabled in GDB.
3009 - Support for the sparc64-linux-gnu target is now included in
3012 - The amd64-linux build of gdbserver now supports debugging both
3013 32-bit and 64-bit programs.
3015 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3016 now support hardware watchpoints, and will use them automatically
3021 GDB now has support for scripting using Python. Whether this is
3022 available is determined at configure time.
3024 New GDB commands can now be written in Python.
3026 * Ada tasking support
3028 Ada tasks can now be inspected in GDB. The following commands have
3032 Print the list of Ada tasks.
3034 Print detailed information about task number N.
3036 Print the task number of the current task.
3038 Switch the context of debugging to task number N.
3040 * Support for user-defined prefixed commands. The "define" command can
3041 add new commands to existing prefixes, e.g. "target".
3043 * Multi-inferior, multi-process debugging.
3045 GDB now has generalized support for multi-inferior debugging. See
3046 "Debugging Multiple Inferiors" in the manual for more information.
3047 Although availability still depends on target support, the command
3048 set is more uniform now. The GNU/Linux specific multi-forks support
3049 has been migrated to this new framework. This implied some user
3050 visible changes; see "New commands" and also "Removed commands"
3053 * Target descriptions can now describe the target OS ABI. See the
3054 "Target Description Format" section in the user manual for more
3057 * Target descriptions can now describe "compatible" architectures
3058 to indicate that the target can execute applications for a different
3059 architecture in addition to those for the main target architecture.
3060 See the "Target Description Format" section in the user manual for
3063 * Multi-architecture debugging.
3065 GDB now includes general supports for debugging applications on
3066 hybrid systems that use more than one single processor architecture
3067 at the same time. Each such hybrid architecture still requires
3068 specific support to be added. The only hybrid architecture supported
3069 in this version of GDB is the Cell Broadband Engine.
3071 * GDB now supports integrated debugging of Cell/B.E. applications that
3072 use both the PPU and SPU architectures. To enable support for hybrid
3073 Cell/B.E. debugging, you need to configure GDB to support both the
3074 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3075 --enable-targets configure option.
3077 * Non-stop mode debugging.
3079 For some targets, GDB now supports an optional mode of operation in
3080 which you can examine stopped threads while other threads continue
3081 to execute freely. This is referred to as non-stop mode, with the
3082 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3083 section in the user manual for more information.
3085 To be able to support remote non-stop debugging, a remote stub needs
3086 to implement the non-stop mode remote protocol extensions, as
3087 described in the "Remote Non-Stop" section of the user manual. The
3088 GDB remote stub, gdbserver, has been adjusted to support these
3089 extensions on linux targets.
3091 * New commands (for set/show, see "New options" below)
3093 catch syscall [NAME(S) | NUMBER(S)]
3094 Catch system calls. Arguments, which should be names of system
3095 calls or their numbers, mean catch only those syscalls. Without
3096 arguments, every syscall will be caught. When the inferior issues
3097 any of the specified syscalls, GDB will stop and announce the system
3098 call, both when it is called and when its call returns. This
3099 feature is currently available with a native GDB running on the
3100 Linux Kernel, under the following architectures: x86, x86_64,
3101 PowerPC and PowerPC64.
3103 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3105 Search memory for a sequence of bytes.
3107 maint set python print-stack
3108 maint show python print-stack
3109 Show a stack trace when an error is encountered in a Python script.
3112 Invoke CODE by passing it to the Python interpreter.
3117 These allow macros to be defined, undefined, and listed
3121 Show operating system information about processes.
3124 List the inferiors currently under GDB's control.
3127 Switch focus to inferior number NUM.
3130 Detach from inferior number NUM.
3133 Kill inferior number NUM.
3137 set spu stop-on-load
3138 show spu stop-on-load
3139 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3141 set spu auto-flush-cache
3142 show spu auto-flush-cache
3143 Control whether to automatically flush the software-managed cache
3144 during Cell/B.E. debugging.
3146 set sh calling-convention
3147 show sh calling-convention
3148 Control the calling convention used when calling SH target functions.
3151 show debug timestamp
3152 Control display of timestamps with GDB debugging output.
3154 set disassemble-next-line
3155 show disassemble-next-line
3156 Control display of disassembled source lines or instructions when
3159 set remote noack-packet
3160 show remote noack-packet
3161 Set/show the use of remote protocol QStartNoAckMode packet. See above
3162 under "New remote packets."
3164 set remote query-attached-packet
3165 show remote query-attached-packet
3166 Control use of remote protocol `qAttached' (query-attached) packet.
3168 set remote read-siginfo-object
3169 show remote read-siginfo-object
3170 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3173 set remote write-siginfo-object
3174 show remote write-siginfo-object
3175 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3178 set remote reverse-continue
3179 show remote reverse-continue
3180 Control use of remote protocol 'bc' (reverse-continue) packet.
3182 set remote reverse-step
3183 show remote reverse-step
3184 Control use of remote protocol 'bs' (reverse-step) packet.
3186 set displaced-stepping
3187 show displaced-stepping
3188 Control displaced stepping mode. Displaced stepping is a way to
3189 single-step over breakpoints without removing them from the debuggee.
3190 Also known as "out-of-line single-stepping".
3193 show debug displaced
3194 Control display of debugging info for displaced stepping.
3196 maint set internal-error
3197 maint show internal-error
3198 Control what GDB does when an internal error is detected.
3200 maint set internal-warning
3201 maint show internal-warning
3202 Control what GDB does when an internal warning is detected.
3207 Use a wrapper program to launch programs for debugging.
3209 set multiple-symbols (all|ask|cancel)
3210 show multiple-symbols
3211 The value of this variable can be changed to adjust the debugger behavior
3212 when an expression or a breakpoint location contains an ambiguous symbol
3213 name (an overloaded function name, for instance).
3215 set breakpoint always-inserted
3216 show breakpoint always-inserted
3217 Keep breakpoints always inserted in the target, as opposed to inserting
3218 them when resuming the target, and removing them when the target stops.
3219 This option can improve debugger performance on slow remote targets.
3221 set arm fallback-mode (arm|thumb|auto)
3222 show arm fallback-mode
3223 set arm force-mode (arm|thumb|auto)
3225 These commands control how ARM GDB determines whether instructions
3226 are ARM or Thumb. The default for both settings is auto, which uses
3227 the current CPSR value for instructions without symbols; previous
3228 versions of GDB behaved as if "set arm fallback-mode arm".
3230 set disable-randomization
3231 show disable-randomization
3232 Standalone programs run with the virtual address space randomization enabled
3233 by default on some platforms. This option keeps the addresses stable across
3234 multiple debugging sessions.
3238 Control whether other threads are stopped or not when some thread hits
3243 Requests that asynchronous execution is enabled in the target, if available.
3244 In this case, it's possible to resume target in the background, and interact
3245 with GDB while the target is running. "show target-async" displays the
3246 current state of asynchronous execution of the target.
3248 set target-wide-charset
3249 show target-wide-charset
3250 The target-wide-charset is the name of the character set that GDB
3251 uses when printing characters whose type is wchar_t.
3253 set tcp auto-retry (on|off)
3255 set tcp connect-timeout
3256 show tcp connect-timeout
3257 These commands allow GDB to retry failed TCP connections to a remote stub
3258 with a specified timeout period; this is useful if the stub is launched
3259 in parallel with GDB but may not be ready to accept connections immediately.
3261 set libthread-db-search-path
3262 show libthread-db-search-path
3263 Control list of directories which GDB will search for appropriate
3266 set schedule-multiple (on|off)
3267 show schedule-multiple
3268 Allow GDB to resume all threads of all processes or only threads of
3269 the current process.
3273 Use more aggressive caching for accesses to the stack. This improves
3274 performance of remote debugging (particularly backtraces) without
3275 affecting correctness.
3277 set interactive-mode (on|off|auto)
3278 show interactive-mode
3279 Control whether GDB runs in interactive mode (on) or not (off).
3280 When in interactive mode, GDB waits for the user to answer all
3281 queries. Otherwise, GDB does not wait and assumes the default
3282 answer. When set to auto (the default), GDB determines which
3283 mode to use based on the stdin settings.
3288 For program forks, this is replaced by the new more generic `info
3289 inferiors' command. To list checkpoints, you can still use the
3290 `info checkpoints' command, which was an alias for the `info forks'
3294 Replaced by the new `inferior' command. To switch between
3295 checkpoints, you can still use the `restart' command, which was an
3296 alias for the `fork' command.
3299 This is removed, since some targets don't have a notion of
3300 processes. To switch between processes, you can still use the
3301 `inferior' command using GDB's own inferior number.
3304 For program forks, this is replaced by the new more generic `kill
3305 inferior' command. To delete a checkpoint, you can still use the
3306 `delete checkpoint' command, which was an alias for the `delete
3310 For program forks, this is replaced by the new more generic `detach
3311 inferior' command. To detach a checkpoint, you can still use the
3312 `detach checkpoint' command, which was an alias for the `detach
3315 * New native configurations
3317 x86/x86_64 Darwin i[34567]86-*-darwin*
3319 x86_64 MinGW x86_64-*-mingw*
3323 Lattice Mico32 lm32-*
3324 x86 DICOS i[34567]86-*-dicos*
3325 x86_64 DICOS x86_64-*-dicos*
3328 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3329 (mingw32ce) debugging.
3335 These commands were actually not implemented on any target.
3337 *** Changes in GDB 6.8
3339 * New native configurations
3341 NetBSD/hppa hppa*-*netbsd*
3342 Xtensa GNU/Linux xtensa*-*-linux*
3346 NetBSD/hppa hppa*-*-netbsd*
3347 Xtensa GNU/Lunux xtensa*-*-linux*
3349 * Change in command line behavior -- corefiles vs. process ids.
3351 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3352 attaching to process NUMBER fails, GDB no longer attempts to open a
3353 core file named NUMBER. Attaching to a program using the -c option
3354 is no longer supported. Instead, use the '-p' or '--pid' options.
3356 * GDB can now be built as a native debugger for debugging Windows x86
3357 (mingw32) Portable Executable (PE) programs.
3359 * Pending breakpoints no longer change their number when their address
3362 * GDB now supports breakpoints with multiple locations,
3363 including breakpoints on C++ constructors, inside C++ templates,
3364 and in inlined functions.
3366 * GDB's ability to debug optimized code has been improved. GDB more
3367 accurately identifies function bodies and lexical blocks that occupy
3368 more than one contiguous range of addresses.
3370 * Target descriptions can now describe registers for PowerPC.
3372 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3373 registers on PowerPC targets.
3375 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3376 targets even when the libthread_db library is not available.
3378 * The GDB remote stub, gdbserver, now supports the new file transfer
3379 commands (remote put, remote get, and remote delete).
3381 * The GDB remote stub, gdbserver, now supports run and attach in
3382 extended-remote mode.
3384 * hppa*64*-*-hpux11* target broken
3385 The debugger is unable to start a program and fails with the following
3386 error: "Error trying to get information about dynamic linker".
3387 The gdb-6.7 release is also affected.
3389 * GDB now supports the --enable-targets= configure option to allow
3390 building a single GDB executable that supports multiple remote
3391 target architectures.
3393 * GDB now supports debugging C and C++ programs which use the
3394 Decimal Floating Point extension. In addition, the PowerPC target
3395 now has a set of pseudo-registers to inspect decimal float values
3396 stored in two consecutive float registers.
3398 * The -break-insert MI command can optionally create pending
3401 * Improved support for debugging Ada
3402 Many improvements to the Ada language support have been made. These
3404 - Better support for Ada2005 interface types
3405 - Improved handling of arrays and slices in general
3406 - Better support for Taft-amendment types
3407 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3409 - Improved command completion in Ada
3412 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3417 set print frame-arguments (all|scalars|none)
3418 show print frame-arguments
3419 The value of this variable can be changed to control which argument
3420 values should be printed by the debugger when displaying a frame.
3425 Transfer files to and from a remote target, and delete remote files.
3432 Transfer files to and from a remote target, and delete remote files.
3434 * New remote packets
3441 Open, close, read, write, and delete files on the remote system.
3444 Attach to an existing process on the remote system, in extended-remote
3448 Run a new process on the remote system, in extended-remote mode.
3450 *** Changes in GDB 6.7
3452 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3453 bfd, libiberty and opcodes, as revealed by static analysis donated by
3454 Coverity, Inc. (http://scan.coverity.com).
3456 * When looking up multiply-defined global symbols, GDB will now prefer the
3457 symbol definition in the current shared library if it was built using the
3458 -Bsymbolic linker option.
3460 * When the Text User Interface (TUI) is not configured, GDB will now
3461 recognize the -tui command-line option and print a message that the TUI
3464 * The GDB remote stub, gdbserver, now has lower overhead for high
3465 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3467 * GDB for MIPS targets now autodetects whether a remote target provides
3468 32-bit or 64-bit register values.
3470 * Support for C++ member pointers has been improved.
3472 * GDB now understands XML target descriptions, which specify the
3473 target's overall architecture. GDB can read a description from
3474 a local file or over the remote serial protocol.
3476 * Vectors of single-byte data use a new integer type which is not
3477 automatically displayed as character or string data.
3479 * The /s format now works with the print command. It displays
3480 arrays of single-byte integers and pointers to single-byte integers
3483 * Target descriptions can now describe target-specific registers,
3484 for architectures which have implemented the support (currently
3485 only ARM, M68K, and MIPS).
3487 * GDB and the GDB remote stub, gdbserver, now support the XScale
3490 * The GDB remote stub, gdbserver, has been updated to support
3491 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3492 has been rewritten to use the standard GDB remote protocol.
3494 * GDB can now step into C++ functions which are called through thunks.
3496 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3498 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3499 layout. It also supports a TextSeg= and DataSeg= response when only
3500 segment base addresses (rather than offsets) are available.
3502 * The /i format now outputs any trailing branch delay slot instructions
3503 immediately following the last instruction within the count specified.
3505 * The GDB remote protocol "T" stop reply packet now supports a
3506 "library" response. Combined with the new "qXfer:libraries:read"
3507 packet, this response allows GDB to debug shared libraries on targets
3508 where the operating system manages the list of loaded libraries (e.g.
3509 Windows and SymbianOS).
3511 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3512 (DLLs) on Windows and Windows CE targets.
3514 * GDB now supports a faster verification that a .debug file matches its binary
3515 according to its build-id signature, if the signature is present.
3521 Enable or disable hardware flow control (RTS/CTS) on the serial port
3522 when debugging using remote targets.
3524 set mem inaccessible-by-default
3525 show mem inaccessible-by-default
3526 If the target supplies a memory map, for instance via the remote
3527 protocol's "qXfer:memory-map:read" packet, setting this variable
3528 prevents GDB from accessing memory outside the memory map. This
3529 is useful for targets with memory mapped registers or which react
3530 badly to accesses of unmapped address space.
3532 set breakpoint auto-hw
3533 show breakpoint auto-hw
3534 If the target supplies a memory map, for instance via the remote
3535 protocol's "qXfer:memory-map:read" packet, setting this variable
3536 lets GDB use hardware breakpoints automatically for memory regions
3537 where it can not use software breakpoints. This covers both the
3538 "break" command and internal breakpoints used for other commands
3539 including "next" and "finish".
3542 catch exception unhandled
3543 Stop the program execution when Ada exceptions are raised.
3546 Stop the program execution when an Ada assertion failed.
3550 Set an alternate system root for target files. This is a more
3551 general version of "set solib-absolute-prefix", which is now
3552 an alias to "set sysroot".
3555 Provide extended SPU facility status information. This set of
3556 commands is available only when debugging the Cell/B.E. SPU
3559 * New native configurations
3561 OpenBSD/sh sh*-*openbsd*
3564 unset tdesc filename
3566 Use the specified local file as an XML target description, and do
3567 not query the target for its built-in description.
3571 OpenBSD/sh sh*-*-openbsd*
3572 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3573 Toshiba Media Processor mep-elf
3575 * New remote packets
3578 Ignore the specified signals; pass them directly to the debugged program
3579 without stopping other threads or reporting them to GDB.
3581 qXfer:features:read:
3582 Read an XML target description from the target, which describes its
3587 Read or write contents of an spufs file on the target system. These
3588 packets are available only on the Cell/B.E. SPU architecture.
3590 qXfer:libraries:read:
3591 Report the loaded shared libraries. Combined with new "T" packet
3592 response, this packet allows GDB to debug shared libraries on
3593 targets where the operating system manages the list of loaded
3594 libraries (e.g. Windows and SymbianOS).
3598 Support for these obsolete configurations has been removed.
3606 i[34567]86-*-lynxos*
3607 i[34567]86-*-netware*
3608 i[34567]86-*-sco3.2v5*
3609 i[34567]86-*-sco3.2v4*
3611 i[34567]86-*-sysv4.2*
3614 i[34567]86-*-unixware2*
3615 i[34567]86-*-unixware*
3624 * Other removed features
3631 Various m68k-only ROM monitors.
3638 Various Renesas ROM monitors and debugging interfaces for SH and
3643 Support for a Macraigor serial interface to on-chip debugging.
3644 GDB does not directly support the newer parallel or USB
3649 A debug information format. The predecessor to DWARF 2 and
3650 DWARF 3, which are still supported.
3652 Support for the HP aCC compiler on HP-UX/PA-RISC
3654 SOM-encapsulated symbolic debugging information, automatic
3655 invocation of pxdb, and the aCC custom C++ ABI. This does not
3656 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3657 with aCC can still be debugged on an assembly level.
3659 MIPS ".pdr" sections
3661 A MIPS-specific format used to describe stack frame layout
3662 in debugging information.
3666 GDB could work with an older version of Guile to debug
3667 the interpreter and Scheme programs running in it.
3669 set mips stack-arg-size
3670 set mips saved-gpreg-size
3672 Use "set mips abi" to control parameter passing for MIPS.
3674 *** Changes in GDB 6.6
3679 Cell Broadband Engine SPU spu-elf
3681 * GDB can now be configured as a cross-debugger targeting native Windows
3682 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3683 running on a Windows system over TCP/IP to debug Windows programs.
3685 * The GDB remote stub, gdbserver, has been updated to support Windows and
3686 Cygwin debugging. Both single-threaded and multi-threaded programs are
3689 * The "set trust-readonly-sections" command works again. This command was
3690 broken in GDB 6.3, 6.4, and 6.5.
3692 * The "load" command now supports writing to flash memory, if the remote
3693 stub provides the required support.
3695 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3696 longer requires symbolic debug information (e.g. DWARF-2).
3701 unset substitute-path
3702 show substitute-path
3703 Manage a list of substitution rules that GDB uses to rewrite the name
3704 of the directories where the sources are located. This can be useful
3705 for instance when the sources were moved to a different location
3706 between compilation and debugging.
3710 Print each CLI command as it is executed. Each command is prefixed with
3711 a number of `+' symbols representing the nesting depth.
3712 The source command now has a `-v' option to enable the same feature.
3716 The ARM Demon monitor support (RDP protocol, "target rdp").
3718 Kernel Object Display, an embedded debugging feature which only worked with
3719 an obsolete version of Cisco IOS.
3721 The 'set download-write-size' and 'show download-write-size' commands.
3723 * New remote packets
3726 Tell a stub about GDB client features, and request remote target features.
3727 The first feature implemented is PacketSize, which allows the target to
3728 specify the size of packets it can handle - to minimize the number of
3729 packets required and improve performance when connected to a remote
3733 Fetch an OS auxilliary vector from the remote stub. This packet is a
3734 more efficient replacement for qPart:auxv:read.
3736 qXfer:memory-map:read:
3737 Fetch a memory map from the remote stub, including information about
3738 RAM, ROM, and flash memory devices.
3743 Erase and program a flash memory device.
3745 * Removed remote packets
3748 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3749 used it, and only gdbserver implemented it.
3751 *** Changes in GDB 6.5
3755 Renesas M32C/M16C m32c-elf
3757 Morpho Technologies ms1 ms1-elf
3761 init-if-undefined Initialize a convenience variable, but
3762 only if it doesn't already have a value.
3764 The following commands are presently only implemented for native GNU/Linux:
3766 checkpoint Save a snapshot of the program state.
3768 restart <n> Return the program state to a
3769 previously saved state.
3771 info checkpoints List currently saved checkpoints.
3773 delete-checkpoint <n> Delete a previously saved checkpoint.
3775 set|show detach-on-fork Tell gdb whether to detach from a newly
3776 forked process, or to keep debugging it.
3778 info forks List forks of the user program that
3779 are available to be debugged.
3781 fork <n> Switch to debugging one of several
3782 forks of the user program that are
3783 available to be debugged.
3785 delete-fork <n> Delete a fork from the list of forks
3786 that are available to be debugged (and
3787 kill the forked process).
3789 detach-fork <n> Delete a fork from the list of forks
3790 that are available to be debugged (and
3791 allow the process to continue).
3795 Morpho Technologies ms2 ms1-elf
3797 * Improved Windows host support
3799 GDB now builds as a cross debugger hosted on i686-mingw32, including
3800 native console support, and remote communications using either
3801 network sockets or serial ports.
3803 * Improved Modula-2 language support
3805 GDB can now print most types in the Modula-2 syntax. This includes:
3806 basic types, set types, record types, enumerated types, range types,
3807 pointer types and ARRAY types. Procedure var parameters are correctly
3808 printed and hexadecimal addresses and character constants are also
3809 written in the Modula-2 syntax. Best results can be obtained by using
3810 GNU Modula-2 together with the -gdwarf-2 command line option.
3814 The ARM rdi-share module.
3816 The Netware NLM debug server.
3818 *** Changes in GDB 6.4
3820 * New native configurations
3822 OpenBSD/arm arm*-*-openbsd*
3823 OpenBSD/mips64 mips64-*-openbsd*
3827 Morpho Technologies ms1 ms1-elf
3829 * New command line options
3831 --batch-silent As for --batch, but totally silent.
3832 --return-child-result The debugger will exist with the same value
3833 the child (debugged) program exited with.
3834 --eval-command COMMAND, -ex COMMAND
3835 Execute a single GDB CLI command. This may be
3836 specified multiple times and in conjunction
3837 with the --command (-x) option.
3839 * Deprecated commands removed
3841 The following commands, that were deprecated in 2000, have been
3845 set|show arm disassembly-flavor set|show arm disassembler
3846 othernames set arm disassembler
3847 set|show remotedebug set|show debug remote
3848 set|show archdebug set|show debug arch
3849 set|show eventdebug set|show debug event
3852 * New BSD user-level threads support
3854 It is now possible to debug programs using the user-level threads
3855 library on OpenBSD and FreeBSD. Currently supported (target)
3858 FreeBSD/amd64 x86_64-*-freebsd*
3859 FreeBSD/i386 i386-*-freebsd*
3860 OpenBSD/i386 i386-*-openbsd*
3862 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3863 are not yet supported.
3865 * New support for Matsushita MN10300 w/sim added
3866 (Work in progress). mn10300-elf.
3868 * REMOVED configurations and files
3870 VxWorks and the XDR protocol *-*-vxworks
3871 Motorola MCORE mcore-*-*
3872 National Semiconductor NS32000 ns32k-*-*
3874 * New "set print array-indexes" command
3876 After turning this setting "on", GDB prints the index of each element
3877 when displaying arrays. The default is "off" to preserve the previous
3880 * VAX floating point support
3882 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3884 * User-defined command support
3886 In addition to using $arg0..$arg9 for argument passing, it is now possible
3887 to use $argc to determine now many arguments have been passed. See the
3888 section on user-defined commands in the user manual for more information.
3890 *** Changes in GDB 6.3:
3892 * New command line option
3894 GDB now accepts -l followed by a number to set the timeout for remote
3897 * GDB works with GCC -feliminate-dwarf2-dups
3899 GDB now supports a more compact representation of DWARF-2 debug
3900 information using DW_FORM_ref_addr references. These are produced
3901 by GCC with the option -feliminate-dwarf2-dups and also by some
3902 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3903 to use -feliminate-dwarf2-dups.
3905 * Internationalization
3907 When supported by the host system, GDB will be built with
3908 internationalization (libintl). The task of marking up the sources is
3909 continued, we're looking forward to our first translation.
3913 Initial support for debugging programs compiled with the GNAT
3914 implementation of the Ada programming language has been integrated
3915 into GDB. In this release, support is limited to expression evaluation.
3917 * New native configurations
3919 GNU/Linux/m32r m32r-*-linux-gnu
3923 GDB's remote protocol now includes support for the 'p' packet. This
3924 packet is used to fetch individual registers from a remote inferior.
3926 * END-OF-LIFE registers[] compatibility module
3928 GDB's internal register infrastructure has been completely rewritten.
3929 The new infrastructure making possible the implementation of key new
3930 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3933 GDB 6.3 will be the last release to include the the registers[]
3934 compatibility module that allowed out-of-date configurations to
3935 continue to work. This change directly impacts the following
3945 powerpc bdm protocol
3947 Unless there is activity to revive these configurations, they will be
3948 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3950 * OBSOLETE configurations and files
3952 Configurations that have been declared obsolete in this release have
3953 been commented out. Unless there is activity to revive these
3954 configurations, the next release of GDB will have their sources
3955 permanently REMOVED.
3964 *** Changes in GDB 6.2.1:
3966 * MIPS `break main; run' gave an heuristic-fence-post warning
3968 When attempting to run even a simple program, a warning about
3969 heuristic-fence-post being hit would be reported. This problem has
3972 * MIPS IRIX 'long double' crashed GDB
3974 When examining a long double variable, GDB would get a segmentation
3975 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3976 IRIX long double values).
3980 A bug in the VAX stack code was causing problems with the "next"
3981 command. This problem has been fixed.
3983 *** Changes in GDB 6.2:
3985 * Fix for ``many threads''
3987 On GNU/Linux systems that use the NPTL threads library, a program
3988 rapidly creating and deleting threads would confuse GDB leading to the
3991 ptrace: No such process.
3992 thread_db_get_info: cannot get thread info: generic error
3994 This problem has been fixed.
3996 * "-async" and "-noasync" options removed.
3998 Support for the broken "-noasync" option has been removed (it caused
4001 * New ``start'' command.
4003 This command runs the program until the begining of the main procedure.
4005 * New BSD Kernel Data Access Library (libkvm) interface
4007 Using ``target kvm'' it is now possible to debug kernel core dumps and
4008 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4009 platforms. Currently supported (native-only) configurations are:
4011 FreeBSD/amd64 x86_64-*-freebsd*
4012 FreeBSD/i386 i?86-*-freebsd*
4013 NetBSD/i386 i?86-*-netbsd*
4014 NetBSD/m68k m68*-*-netbsd*
4015 NetBSD/sparc sparc-*-netbsd*
4016 OpenBSD/amd64 x86_64-*-openbsd*
4017 OpenBSD/i386 i?86-*-openbsd*
4018 OpenBSD/m68k m68*-openbsd*
4019 OpenBSD/sparc sparc-*-openbsd*
4021 * Signal trampoline code overhauled
4023 Many generic problems with GDB's signal handling code have been fixed.
4024 These include: backtraces through non-contiguous stacks; recognition
4025 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4026 call; backtrace through a signal trampoline; step into and out of
4027 signal handlers; and single-stepping in the signal trampoline.
4029 Please note that kernel bugs are a limiting factor here. These
4030 features have been shown to work on an s390 GNU/Linux system that
4031 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4033 * Cygwin support for DWARF 2 added.
4035 * New native configurations
4037 GNU/Linux/hppa hppa*-*-linux*
4038 OpenBSD/hppa hppa*-*-openbsd*
4039 OpenBSD/m68k m68*-*-openbsd*
4040 OpenBSD/m88k m88*-*-openbsd*
4041 OpenBSD/powerpc powerpc-*-openbsd*
4042 NetBSD/vax vax-*-netbsd*
4043 OpenBSD/vax vax-*-openbsd*
4045 * END-OF-LIFE frame compatibility module
4047 GDB's internal frame infrastructure has been completely rewritten.
4048 The new infrastructure making it possible to support key new features
4049 including DWARF 2 Call Frame Information. To aid in the task of
4050 migrating old configurations to this new infrastructure, a
4051 compatibility module, that allowed old configurations to continue to
4052 work, was also included.
4054 GDB 6.2 will be the last release to include this frame compatibility
4055 module. This change directly impacts the following configurations:
4065 Unless there is activity to revive these configurations, they will be
4066 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4068 * REMOVED configurations and files
4070 Sun 3, running SunOS 3 m68*-*-sunos3*
4071 Sun 3, running SunOS 4 m68*-*-sunos4*
4072 Sun 2, running SunOS 3 m68000-*-sunos3*
4073 Sun 2, running SunOS 4 m68000-*-sunos4*
4074 Motorola 680x0 running LynxOS m68*-*-lynxos*
4075 AT&T 3b1/Unix pc m68*-att-*
4076 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4077 decstation mips-dec-* mips-little-*
4078 riscos mips-*-riscos* mips-*-sysv*
4079 sonymips mips-sony-*
4080 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4082 *** Changes in GDB 6.1.1:
4084 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4086 The TUI (Text-mode User Interface) is now built as part of a default
4087 GDB configuration. It is enabled by either selecting the TUI with the
4088 command line option "-i=tui" or by running the separate "gdbtui"
4089 program. For more information on the TUI, see the manual "Debugging
4092 * Pending breakpoint support (also included in GDB 6.1)
4094 Support has been added to allow you to specify breakpoints in shared
4095 libraries that have not yet been loaded. If a breakpoint location
4096 cannot be found, and the "breakpoint pending" option is set to auto,
4097 GDB queries you if you wish to make the breakpoint pending on a future
4098 shared-library load. If and when GDB resolves the breakpoint symbol,
4099 the pending breakpoint is removed as one or more regular breakpoints
4102 Pending breakpoints are very useful for GCJ Java debugging.
4104 * Fixed ISO-C build problems
4106 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4107 non ISO-C code that stopped them being built using a more strict ISO-C
4108 compiler (e.g., IBM's C compiler).
4110 * Fixed build problem on IRIX 5
4112 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4113 wasn't able to compile compile on an IRIX 5 system.
4115 * Added execute permission to gdb/gdbserver/configure
4117 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4118 permission. This bug would cause configure to fail on a number of
4119 systems (Solaris, IRIX). Ref: server/519.
4121 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4123 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4124 has been updated to use constant array sizes.
4126 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4128 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4129 its generated DWARF Call Frame Info. This encoding was causing GDB to
4130 panic, that panic has been fixed. Ref: gdb/1628.
4132 * Fixed a problem when examining parameters in shared library code.
4134 When examining parameters in optimized shared library code generated
4135 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4136 not available''. GDB now correctly displays the variable's value.
4138 *** Changes in GDB 6.1:
4140 * Removed --with-mmalloc
4142 Support for the mmalloc memory manager has been removed, as it
4143 conflicted with the internal gdb byte cache.
4145 * Changes in AMD64 configurations
4147 The AMD64 target now includes the %cs and %ss registers. As a result
4148 the AMD64 remote protocol has changed; this affects the floating-point
4149 and SSE registers. If you rely on those registers for your debugging,
4150 you should upgrade gdbserver on the remote side.
4152 * Revised SPARC target
4154 The SPARC target has been completely revised, incorporating the
4155 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4156 support for LynxOS and SunOS 4 has been dropped. Calling functions
4157 from within GDB on operating systems with a non-executable stack
4158 (Solaris, OpenBSD) now works.
4162 GDB has a new C++ demangler which does a better job on the mangled
4163 names generated by current versions of g++. It also runs faster, so
4164 with this and other changes gdb should now start faster on large C++
4167 * DWARF 2 Location Expressions
4169 GDB support for location expressions has been extended to support function
4170 arguments and frame bases. Older versions of GDB could crash when they
4173 * C++ nested types and namespaces
4175 GDB's support for nested types and namespaces in C++ has been
4176 improved, especially if you use the DWARF 2 debugging format. (This
4177 is the default for recent versions of GCC on most platforms.)
4178 Specifically, if you have a class "Inner" defined within a class or
4179 namespace "Outer", then GDB realizes that the class's name is
4180 "Outer::Inner", not simply "Inner". This should greatly reduce the
4181 frequency of complaints about not finding RTTI symbols. In addition,
4182 if you are stopped at inside of a function defined within a namespace,
4183 GDB modifies its name lookup accordingly.
4185 * New native configurations
4187 NetBSD/amd64 x86_64-*-netbsd*
4188 OpenBSD/amd64 x86_64-*-openbsd*
4189 OpenBSD/alpha alpha*-*-openbsd*
4190 OpenBSD/sparc sparc-*-openbsd*
4191 OpenBSD/sparc64 sparc64-*-openbsd*
4193 * New debugging protocols
4195 M32R with SDI protocol m32r-*-elf*
4197 * "set prompt-escape-char" command deleted.
4199 The command "set prompt-escape-char" has been deleted. This command,
4200 and its very obscure effet on GDB's prompt, was never documented,
4201 tested, nor mentioned in the NEWS file.
4203 * OBSOLETE configurations and files
4205 Configurations that have been declared obsolete in this release have
4206 been commented out. Unless there is activity to revive these
4207 configurations, the next release of GDB will have their sources
4208 permanently REMOVED.
4210 Sun 3, running SunOS 3 m68*-*-sunos3*
4211 Sun 3, running SunOS 4 m68*-*-sunos4*
4212 Sun 2, running SunOS 3 m68000-*-sunos3*
4213 Sun 2, running SunOS 4 m68000-*-sunos4*
4214 Motorola 680x0 running LynxOS m68*-*-lynxos*
4215 AT&T 3b1/Unix pc m68*-att-*
4216 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4217 decstation mips-dec-* mips-little-*
4218 riscos mips-*-riscos* mips-*-sysv*
4219 sonymips mips-sony-*
4220 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4222 * REMOVED configurations and files
4224 SGI Irix-4.x mips-sgi-irix4 or iris4
4225 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4226 Z8000 simulator z8k-zilog-none or z8ksim
4227 Matsushita MN10200 w/simulator mn10200-*-*
4228 H8/500 simulator h8500-hitachi-hms or h8500hms
4229 HP/PA running BSD hppa*-*-bsd*
4230 HP/PA running OSF/1 hppa*-*-osf*
4231 HP/PA Pro target hppa*-*-pro*
4232 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4233 386BSD i[3456]86-*-bsd*
4234 Sequent family i[3456]86-sequent-sysv4*
4235 i[3456]86-sequent-sysv*
4236 i[3456]86-sequent-bsd*
4237 SPARC running LynxOS sparc-*-lynxos*
4238 SPARC running SunOS 4 sparc-*-sunos4*
4239 Tsqware Sparclet sparclet-*-*
4240 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4242 *** Changes in GDB 6.0:
4246 Support for debugging the Objective-C programming language has been
4247 integrated into GDB.
4249 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4251 DWARF 2's Call Frame Information makes available compiler generated
4252 information that more exactly describes the program's run-time stack.
4253 By using this information, GDB is able to provide more robust stack
4256 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4257 have been updated to use a new backtrace mechanism which includes
4258 DWARF 2 CFI support.
4262 GDB's remote protocol has been extended to include support for hosted
4263 file I/O (where the remote target uses GDB's file system). See GDB's
4264 remote protocol documentation for details.
4266 * All targets using the new architecture framework.
4268 All of GDB's targets have been updated to use the new internal
4269 architecture framework. The way is now open for future GDB releases
4270 to include cross-architecture native debugging support (i386 on amd64,
4273 * GNU/Linux's Thread Local Storage (TLS)
4275 GDB now includes support for for the GNU/Linux implementation of
4276 per-thread variables.
4278 * GNU/Linux's Native POSIX Thread Library (NPTL)
4280 GDB's thread code has been updated to work with either the new
4281 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4283 * Separate debug info.
4285 GDB, in conjunction with BINUTILS, now supports a mechanism for
4286 automatically loading debug information from a separate file. Instead
4287 of shipping full debug and non-debug versions of system libraries,
4288 system integrators can now instead ship just the stripped libraries
4289 and optional debug files.
4291 * DWARF 2 Location Expressions
4293 DWARF 2 Location Expressions allow the compiler to more completely
4294 describe the location of variables (even in optimized code) to the
4297 GDB now includes preliminary support for location expressions (support
4298 for DW_OP_piece is still missing).
4302 A number of long standing bugs that caused GDB to die while starting a
4303 Java application have been fixed. GDB's Java support is now
4304 considered "useable".
4306 * GNU/Linux support for fork, vfork, and exec.
4308 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4309 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4312 * GDB supports logging output to a file
4314 There are two new commands, "set logging" and "show logging", which can be
4315 used to capture GDB's output to a file.
4317 * The meaning of "detach" has changed for gdbserver
4319 The "detach" command will now resume the application, as documented. To
4320 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4323 * d10v, m68hc11 `regs' command deprecated
4325 The `info registers' command has been updated so that it displays the
4326 registers using a format identical to the old `regs' command.
4330 A new command, "maint set profile on/off", has been added. This command can
4331 be used to enable or disable profiling while running GDB, to profile a
4332 session or a set of commands. In addition there is a new configure switch,
4333 "--enable-profiling", which will cause GDB to be compiled with profiling
4334 data, for more informative profiling results.
4336 * Default MI syntax changed to "mi2".
4338 The default MI (machine interface) syntax, enabled by the command line
4339 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4340 "mi1", can be enabled by specifying the option "-i=mi1".
4342 Support for the original "mi0" syntax (included in GDB 5.0) has been
4345 Fix for gdb/192: removed extraneous space when displaying frame level.
4346 Fix for gdb/672: update changelist is now output in mi list format.
4347 Fix for gdb/702: a -var-assign that updates the value now shows up
4348 in a subsequent -var-update.
4350 * New native configurations.
4352 FreeBSD/amd64 x86_64-*-freebsd*
4354 * Multi-arched targets.
4356 HP/PA HPUX11 hppa*-*-hpux*
4357 Renesas M32R/D w/simulator m32r-*-elf*
4359 * OBSOLETE configurations and files
4361 Configurations that have been declared obsolete in this release have
4362 been commented out. Unless there is activity to revive these
4363 configurations, the next release of GDB will have their sources
4364 permanently REMOVED.
4366 Z8000 simulator z8k-zilog-none or z8ksim
4367 Matsushita MN10200 w/simulator mn10200-*-*
4368 H8/500 simulator h8500-hitachi-hms or h8500hms
4369 HP/PA running BSD hppa*-*-bsd*
4370 HP/PA running OSF/1 hppa*-*-osf*
4371 HP/PA Pro target hppa*-*-pro*
4372 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4373 Sequent family i[3456]86-sequent-sysv4*
4374 i[3456]86-sequent-sysv*
4375 i[3456]86-sequent-bsd*
4376 Tsqware Sparclet sparclet-*-*
4377 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4379 * REMOVED configurations and files
4382 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4383 IBM AIX PS/2 i[3456]86-*-aix
4384 i386 running Mach 3.0 i[3456]86-*-mach3*
4385 i386 running Mach i[3456]86-*-mach*
4386 i386 running OSF/1 i[3456]86-*osf1mk*
4387 HP/Apollo 68k Family m68*-apollo*-sysv*,
4389 m68*-hp-bsd*, m68*-hp-hpux*
4390 Argonaut Risc Chip (ARC) arc-*-*
4391 Mitsubishi D30V d30v-*-*
4392 Fujitsu FR30 fr30-*-elf*
4393 OS/9000 i[34]86-*-os9k
4394 I960 with MON960 i960-*-coff
4396 * MIPS $fp behavior changed
4398 The convenience variable $fp, for the MIPS, now consistently returns
4399 the address of the current frame's base. Previously, depending on the
4400 context, $fp could refer to either $sp or the current frame's base
4401 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4402 The GNU Source-Level Debugger''.
4404 *** Changes in GDB 5.3:
4406 * GNU/Linux shared library multi-threaded performance improved.
4408 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4409 `/proc', in preference to `ptrace' for memory reads. This may result
4410 in an improvement in the start-up time of multi-threaded, shared
4411 library applications when run under GDB. One GDB user writes: ``loads
4412 shared libs like mad''.
4414 * ``gdbserver'' now supports multi-threaded applications on some targets
4416 Support for debugging multi-threaded applications which use
4417 the GNU/Linux LinuxThreads package has been added for
4418 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4419 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4421 * GDB now supports C/C++ preprocessor macros.
4423 GDB now expands preprocessor macro invocations in C/C++ expressions,
4424 and provides various commands for showing macro definitions and how
4427 The new command `macro expand EXPRESSION' expands any macro
4428 invocations in expression, and shows the result.
4430 The new command `show macro MACRO-NAME' shows the definition of the
4431 macro named MACRO-NAME, and where it was defined.
4433 Most compilers don't include information about macros in the debugging
4434 information by default. In GCC 3.1, for example, you need to compile
4435 your program with the options `-gdwarf-2 -g3'. If the macro
4436 information is present in the executable, GDB will read it.
4438 * Multi-arched targets.
4440 DEC Alpha (partial) alpha*-*-*
4441 DEC VAX (partial) vax-*-*
4443 National Semiconductor NS32000 (partial) ns32k-*-*
4444 Motorola 68000 (partial) m68k-*-*
4445 Motorola MCORE mcore-*-*
4449 Fujitsu FRV architecture added by Red Hat frv*-*-*
4452 * New native configurations
4454 Alpha NetBSD alpha*-*-netbsd*
4455 SH NetBSD sh*-*-netbsdelf*
4456 MIPS NetBSD mips*-*-netbsd*
4457 UltraSPARC NetBSD sparc64-*-netbsd*
4459 * OBSOLETE configurations and files
4461 Configurations that have been declared obsolete in this release have
4462 been commented out. Unless there is activity to revive these
4463 configurations, the next release of GDB will have their sources
4464 permanently REMOVED.
4466 Mitsubishi D30V d30v-*-*
4467 OS/9000 i[34]86-*-os9k
4468 IBM AIX PS/2 i[3456]86-*-aix
4469 Fujitsu FR30 fr30-*-elf*
4470 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4471 Argonaut Risc Chip (ARC) arc-*-*
4472 i386 running Mach 3.0 i[3456]86-*-mach3*
4473 i386 running Mach i[3456]86-*-mach*
4474 i386 running OSF/1 i[3456]86-*osf1mk*
4475 HP/Apollo 68k Family m68*-apollo*-sysv*,
4477 m68*-hp-bsd*, m68*-hp-hpux*
4478 I960 with MON960 i960-*-coff
4480 * OBSOLETE languages
4482 CHILL, a Pascal like language used by telecommunications companies.
4484 * REMOVED configurations and files
4486 AMD 29k family via UDI a29k-amd-udi, udi29k
4487 A29K VxWorks a29k-*-vxworks
4488 AMD 29000 embedded, using EBMON a29k-none-none
4489 AMD 29000 embedded with COFF a29k-none-coff
4490 AMD 29000 embedded with a.out a29k-none-aout
4492 testsuite/gdb.hp/gdb.threads-hp/ directory
4494 * New command "set max-user-call-depth <nnn>"
4496 This command allows the user to limit the call depth of user-defined
4497 commands. The default is 1024.
4499 * Changes in FreeBSD/i386 native debugging.
4501 Support for the "generate-core-file" has been added.
4503 * New commands "dump", "append", and "restore".
4505 These commands allow data to be copied from target memory
4506 to a bfd-format or binary file (dump and append), and back
4507 from a file into memory (restore).
4509 * Improved "next/step" support on multi-processor Alpha Tru64.
4511 The previous single-step mechanism could cause unpredictable problems,
4512 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4513 of a software single-step mechanism prevents this.
4515 *** Changes in GDB 5.2.1:
4523 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4524 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4525 Fix, by Joel Brobecker imported from mainline.
4527 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4528 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4529 Fix, by Fred Fish, imported from mainline.
4531 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4532 Surprisingly enough, it works now.
4533 By Michal Ludvig, imported from mainline.
4535 i386 hardware watchpoint support:
4536 avoid misses on second run for some targets.
4537 By Pierre Muller, imported from mainline.
4539 *** Changes in GDB 5.2:
4541 * New command "set trust-readonly-sections on[off]".
4543 This command is a hint that tells gdb that read-only sections
4544 really are read-only (ie. that their contents will not change).
4545 In this mode, gdb will go to the object file rather than the
4546 target to read memory from read-only sections (such as ".text").
4547 This can be a significant performance improvement on some
4548 (notably embedded) targets.
4550 * New command "generate-core-file" (or "gcore").
4552 This new gdb command allows the user to drop a core file of the child
4553 process state at any time. So far it's been implemented only for
4554 GNU/Linux and Solaris, but should be relatively easily ported to other
4555 hosts. Argument is core file name (defaults to core.<pid>).
4557 * New command line option
4559 GDB now accepts --pid or -p followed by a process id.
4561 * Change in command line behavior -- corefiles vs. process ids.
4563 There is a subtle behavior in the way in which GDB handles
4564 command line arguments. The first non-flag argument is always
4565 a program to debug, but the second non-flag argument may either
4566 be a corefile or a process id. Previously, GDB would attempt to
4567 open the second argument as a corefile, and if that failed, would
4568 issue a superfluous error message and then attempt to attach it as
4569 a process. Now, if the second argument begins with a non-digit,
4570 it will be treated as a corefile. If it begins with a digit,
4571 GDB will attempt to attach it as a process, and if no such process
4572 is found, will then attempt to open it as a corefile.
4574 * Changes in ARM configurations.
4576 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4577 configuration is fully multi-arch.
4579 * New native configurations
4581 ARM NetBSD arm*-*-netbsd*
4582 x86 OpenBSD i[3456]86-*-openbsd*
4583 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4584 Sparc64 running FreeBSD sparc64-*-freebsd*
4588 Sanyo XStormy16 xstormy16-elf
4590 * OBSOLETE configurations and files
4592 Configurations that have been declared obsolete in this release have
4593 been commented out. Unless there is activity to revive these
4594 configurations, the next release of GDB will have their sources
4595 permanently REMOVED.
4597 AMD 29k family via UDI a29k-amd-udi, udi29k
4598 A29K VxWorks a29k-*-vxworks
4599 AMD 29000 embedded, using EBMON a29k-none-none
4600 AMD 29000 embedded with COFF a29k-none-coff
4601 AMD 29000 embedded with a.out a29k-none-aout
4603 testsuite/gdb.hp/gdb.threads-hp/ directory
4605 * REMOVED configurations and files
4607 TI TMS320C80 tic80-*-*
4609 PowerPC Solaris powerpcle-*-solaris*
4610 PowerPC Windows NT powerpcle-*-cygwin32
4611 PowerPC Netware powerpc-*-netware*
4612 Harris/CXUX m88k m88*-harris-cxux*
4613 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4614 ns32k-utek-sysv* ns32k-utek-*
4615 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4616 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4617 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4618 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4619 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4621 * Changes to command line processing
4623 The new `--args' feature can be used to specify command-line arguments
4624 for the inferior from gdb's command line.
4626 * Changes to key bindings
4628 There is a new `operate-and-get-next' function bound to `C-o'.
4630 *** Changes in GDB 5.1.1
4632 Fix compile problem on DJGPP.
4634 Fix a problem with floating-point registers on the i386 being
4637 Fix to stop GDB crashing on .debug_str debug info.
4639 Numerous documentation fixes.
4641 Numerous testsuite fixes.
4643 *** Changes in GDB 5.1:
4645 * New native configurations
4647 Alpha FreeBSD alpha*-*-freebsd*
4648 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4649 MIPS GNU/Linux mips*-*-linux*
4650 MIPS SGI Irix 6.x mips*-sgi-irix6*
4651 ia64 AIX ia64-*-aix*
4652 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4656 Motorola 68HC11 and 68HC12 m68hc11-elf
4658 UltraSparc running GNU/Linux sparc64-*-linux*
4660 * OBSOLETE configurations and files
4662 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4663 Harris/CXUX m88k m88*-harris-cxux*
4664 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4665 ns32k-utek-sysv* ns32k-utek-*
4666 TI TMS320C80 tic80-*-*
4668 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4669 PowerPC Solaris powerpcle-*-solaris*
4670 PowerPC Windows NT powerpcle-*-cygwin32
4671 PowerPC Netware powerpc-*-netware*
4672 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4673 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4674 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4675 Apple Macintosh (MPW) host N/A
4677 stuff.c (Program to stuff files into a specially prepared space in kdb)
4678 kdb-start.c (Main loop for the standalone kernel debugger)
4680 Configurations that have been declared obsolete in this release have
4681 been commented out. Unless there is activity to revive these
4682 configurations, the next release of GDB will have their sources
4683 permanently REMOVED.
4685 * REMOVED configurations and files
4687 Altos 3068 m68*-altos-*
4688 Convex c1-*-*, c2-*-*
4690 ARM RISCix arm-*-* (as host)
4694 * GDB has been converted to ISO C.
4696 GDB's source code has been converted to ISO C. In particular, the
4697 sources are fully protoized, and rely on standard headers being
4702 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4704 * The MI enabled by default.
4706 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4707 revised and enabled by default. Packages which use GDB as a debugging
4708 engine behind a UI or another front end are encouraged to switch to
4709 using the GDB/MI interface, instead of the old annotations interface
4710 which is now deprecated.
4712 * Support for debugging Pascal programs.
4714 GDB now includes support for debugging Pascal programs. The following
4715 main features are supported:
4717 - Pascal-specific data types such as sets;
4719 - automatic recognition of Pascal sources based on file-name
4722 - Pascal-style display of data types, variables, and functions;
4724 - a Pascal expression parser.
4726 However, some important features are not yet supported.
4728 - Pascal string operations are not supported at all;
4730 - there are some problems with boolean types;
4732 - Pascal type hexadecimal constants are not supported
4733 because they conflict with the internal variables format;
4735 - support for Pascal objects and classes is not full yet;
4737 - unlike Pascal, GDB is case-sensitive for symbol names.
4739 * Changes in completion.
4741 Commands such as `shell', `run' and `set args', which pass arguments
4742 to inferior programs, now complete on file names, similar to what
4743 users expect at the shell prompt.
4745 Commands which accept locations, such as `disassemble', `print',
4746 `breakpoint', `until', etc. now complete on filenames as well as
4747 program symbols. Thus, if you type "break foob TAB", and the source
4748 files linked into the programs include `foobar.c', that file name will
4749 be one of the candidates for completion. However, file names are not
4750 considered for completion after you typed a colon that delimits a file
4751 name from a name of a function in that file, as in "break foo.c:bar".
4753 `set demangle-style' completes on available demangling styles.
4755 * New platform-independent commands:
4757 It is now possible to define a post-hook for a command as well as a
4758 hook that runs before the command. For more details, see the
4759 documentation of `hookpost' in the GDB manual.
4761 * Changes in GNU/Linux native debugging.
4763 Support for debugging multi-threaded programs has been completely
4764 revised for all platforms except m68k and sparc. You can now debug as
4765 many threads as your system allows you to have.
4767 Attach/detach is supported for multi-threaded programs.
4769 Support for SSE registers was added for x86. This doesn't work for
4770 multi-threaded programs though.
4772 * Changes in MIPS configurations.
4774 Multi-arch support is enabled for all MIPS configurations.
4776 GDB can now be built as native debugger on SGI Irix 6.x systems for
4777 debugging n32 executables. (Debugging 64-bit executables is not yet
4780 * Unified support for hardware watchpoints in all x86 configurations.
4782 Most (if not all) native x86 configurations support hardware-assisted
4783 breakpoints and watchpoints in a unified manner. This support
4784 implements debug register sharing between watchpoints, which allows to
4785 put a virtually infinite number of watchpoints on the same address,
4786 and also supports watching regions up to 16 bytes with several debug
4789 The new maintenance command `maintenance show-debug-regs' toggles
4790 debugging print-outs in functions that insert, remove, and test
4791 watchpoints and hardware breakpoints.
4793 * Changes in the DJGPP native configuration.
4795 New command ``info dos sysinfo'' displays assorted information about
4796 the CPU, OS, memory, and DPMI server.
4798 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4799 display information about segment descriptors stored in GDT, LDT, and
4802 New commands ``info dos pde'' and ``info dos pte'' display entries
4803 from Page Directory and Page Tables (for now works with CWSDPMI only).
4804 New command ``info dos address-pte'' displays the Page Table entry for
4805 a given linear address.
4807 GDB can now pass command lines longer than 126 characters to the
4808 program being debugged (requires an update to the libdbg.a library
4809 which is part of the DJGPP development kit).
4811 DWARF2 debug info is now supported.
4813 It is now possible to `step' and `next' through calls to `longjmp'.
4815 * Changes in documentation.
4817 All GDB documentation was converted to GFDL, the GNU Free
4818 Documentation License.
4820 Tracepoints-related commands are now fully documented in the GDB
4823 TUI, the Text-mode User Interface, is now documented in the manual.
4825 Tracepoints-related commands are now fully documented in the GDB
4828 The "GDB Internals" manual now has an index. It also includes
4829 documentation of `ui_out' functions, GDB coding standards, x86
4830 hardware watchpoints, and memory region attributes.
4832 * GDB's version number moved to ``version.in''
4834 The Makefile variable VERSION has been replaced by the file
4835 ``version.in''. People creating GDB distributions should update the
4836 contents of this file.
4840 GUD support is now a standard part of the EMACS distribution.
4842 *** Changes in GDB 5.0:
4844 * Improved support for debugging FP programs on x86 targets
4846 Unified and much-improved support for debugging floating-point
4847 programs on all x86 targets. In particular, ``info float'' now
4848 displays the FP registers in the same format on all x86 targets, with
4849 greater level of detail.
4851 * Improvements and bugfixes in hardware-assisted watchpoints
4853 It is now possible to watch array elements, struct members, and
4854 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4855 on x86 targets no longer erroneously trigger when the address is
4858 * Improvements in the native DJGPP version of GDB
4860 The distribution now includes all the scripts and auxiliary files
4861 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4862 machines ``out of the box''.
4864 The DJGPP version can now debug programs that use signals. It is
4865 possible to catch signals that happened in the debuggee, deliver
4866 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4867 would kill the program being debugged.) Programs that hook hardware
4868 interrupts (keyboard, timer, etc.) can also be debugged.
4870 It is now possible to debug DJGPP programs that redirect their
4871 standard handles or switch them to raw (as opposed to cooked) mode, or
4872 even close them. The command ``run < foo > bar'' works as expected,
4873 and ``info terminal'' reports useful information about the debuggee's
4874 terminal, including raw/cooked mode, redirection, etc.
4876 The DJGPP version now uses termios functions for console I/O, which
4877 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4880 DOS-style file names with drive letters are now fully supported by
4883 It is now possible to debug DJGPP programs that switch their working
4884 directory. It is also possible to rerun the debuggee any number of
4885 times without restarting GDB; thus, you can use the same setup,
4886 breakpoints, etc. for many debugging sessions.
4888 * New native configurations
4890 ARM GNU/Linux arm*-*-linux*
4891 PowerPC GNU/Linux powerpc-*-linux*
4895 Motorola MCore mcore-*-*
4896 x86 VxWorks i[3456]86-*-vxworks*
4897 PowerPC VxWorks powerpc-*-vxworks*
4898 TI TMS320C80 tic80-*-*
4900 * OBSOLETE configurations
4902 Altos 3068 m68*-altos-*
4903 Convex c1-*-*, c2-*-*
4905 ARM RISCix arm-*-* (as host)
4908 Configurations that have been declared obsolete will be commented out,
4909 but the code will be left in place. If there is no activity to revive
4910 these configurations before the next release of GDB, the sources will
4911 be permanently REMOVED.
4913 * Gould support removed
4915 Support for the Gould PowerNode and NP1 has been removed.
4917 * New features for SVR4
4919 On SVR4 native platforms (such as Solaris), if you attach to a process
4920 without first loading a symbol file, GDB will now attempt to locate and
4921 load symbols from the running process's executable file.
4923 * Many C++ enhancements
4925 C++ support has been greatly improved. Overload resolution now works properly
4926 in almost all cases. RTTI support is on the way.
4928 * Remote targets can connect to a sub-program
4930 A popen(3) style serial-device has been added. This device starts a
4931 sub-process (such as a stand-alone simulator) and then communicates
4932 with that. The sub-program to run is specified using the syntax
4933 ``|<program> <args>'' vis:
4935 (gdb) set remotedebug 1
4936 (gdb) target extended-remote |mn10300-elf-sim program-args
4938 * MIPS 64 remote protocol
4940 A long standing bug in the mips64 remote protocol where by GDB
4941 expected certain 32 bit registers (ex SR) to be transfered as 32
4942 instead of 64 bits has been fixed.
4944 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4945 added to provide backward compatibility with older versions of GDB.
4947 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4949 The command ``set remotebinarydownload'' command has been replaced by
4950 ``set remote X-packet''. Other commands in ``set remote'' family
4951 include ``set remote P-packet''.
4953 * Breakpoint commands accept ranges.
4955 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4956 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4957 ``tracepoint passcount'' also accepts a range of tracepoints.
4959 * ``apropos'' command added.
4961 The ``apropos'' command searches through command names and
4962 documentation strings, printing out matches, making it much easier to
4963 try to find a command that does what you are looking for.
4967 A new machine oriented interface (MI) has been added to GDB. This
4968 interface is designed for debug environments running GDB as a separate
4969 process. This is part of the long term libGDB project. See the
4970 "GDB/MI" chapter of the GDB manual for further information. It can be
4971 enabled by configuring with:
4973 .../configure --enable-gdbmi
4975 *** Changes in GDB-4.18:
4977 * New native configurations
4979 HP-UX 10.20 hppa*-*-hpux10.20
4980 HP-UX 11.x hppa*-*-hpux11.0*
4981 M68K GNU/Linux m68*-*-linux*
4985 Fujitsu FR30 fr30-*-elf*
4986 Intel StrongARM strongarm-*-*
4987 Mitsubishi D30V d30v-*-*
4989 * OBSOLETE configurations
4991 Gould PowerNode, NP1 np1-*-*, pn-*-*
4993 Configurations that have been declared obsolete will be commented out,
4994 but the code will be left in place. If there is no activity to revive
4995 these configurations before the next release of GDB, the sources will
4996 be permanently REMOVED.
5000 As a compatibility experiment, GDB's source files buildsym.h and
5001 buildsym.c have been converted to pure standard C, no longer
5002 containing any K&R compatibility code. We believe that all systems in
5003 use today either come with a standard C compiler, or have a GCC port
5004 available. If this is not true, please report the affected
5005 configuration to bug-gdb@gnu.org immediately. See the README file for
5006 information about getting a standard C compiler if you don't have one
5011 GDB now uses readline 2.2.
5013 * set extension-language
5015 You can now control the mapping between filename extensions and source
5016 languages by using the `set extension-language' command. For instance,
5017 you can ask GDB to treat .c files as C++ by saying
5018 set extension-language .c c++
5019 The command `info extensions' lists all of the recognized extensions
5020 and their associated languages.
5022 * Setting processor type for PowerPC and RS/6000
5024 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5025 you can use the `set processor' command to specify what variant of the
5026 PowerPC family you are debugging. The command
5030 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5031 following PowerPC and RS6000 variants:
5033 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5034 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5036 403GC IBM PowerPC 403GC
5037 505 Motorola PowerPC 505
5038 860 Motorola PowerPC 860 or 850
5039 601 Motorola PowerPC 601
5040 602 Motorola PowerPC 602
5041 603 Motorola/IBM PowerPC 603 or 603e
5042 604 Motorola PowerPC 604 or 604e
5043 750 Motorola/IBM PowerPC 750 or 750
5045 At the moment, this command just tells GDB what to name the
5046 special-purpose processor registers. Since almost all the affected
5047 registers are inaccessible to user-level programs, this command is
5048 only useful for remote debugging in its present form.
5052 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5053 more extensive support for HP-UX. Added features include shared
5054 library support, kernel threads and hardware watchpoints for 11.00,
5055 support for HP's ANSI C and C++ compilers, and a compatibility mode
5056 for xdb and dbx commands.
5060 HP's donation includes the new concept of catchpoints, which is a
5061 generalization of the old catch command. On HP-UX, it is now possible
5062 to catch exec, fork, and vfork, as well as library loading.
5064 This means that the existing catch command has changed; its first
5065 argument now specifies the type of catch to be set up. See the
5066 output of "help catch" for a list of catchpoint types.
5068 * Debugging across forks
5070 On HP-UX, you can choose which process to debug when a fork() happens
5075 HP has donated a curses-based terminal user interface (TUI). To get
5076 it, build with --enable-tui. Although this can be enabled for any
5077 configuration, at present it only works for native HP debugging.
5079 * GDB remote protocol additions
5081 A new protocol packet 'X' that writes binary data is now available.
5082 Default behavior is to try 'X', then drop back to 'M' if the stub
5083 fails to respond. The settable variable `remotebinarydownload'
5084 allows explicit control over the use of 'X'.
5086 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5087 full 64-bit address. The command
5089 set remoteaddresssize 32
5091 can be used to revert to the old behaviour. For existing remote stubs
5092 the change should not be noticed, as the additional address information
5095 In order to assist in debugging stubs, you may use the maintenance
5096 command `packet' to send any text string to the stub. For instance,
5098 maint packet heythere
5100 sends the packet "$heythere#<checksum>". Note that it is very easy to
5101 disrupt a debugging session by sending the wrong packet at the wrong
5104 The compare-sections command allows you to compare section data on the
5105 target to what is in the executable file without uploading or
5106 downloading, by comparing CRC checksums.
5108 * Tracing can collect general expressions
5110 You may now collect general expressions at tracepoints. This requires
5111 further additions to the target-side stub; see tracepoint.c and
5112 doc/agentexpr.texi for further details.
5114 * mask-address variable for Mips
5116 For Mips targets, you may control the zeroing of the upper 32 bits of
5117 a 64-bit address by entering `set mask-address on'. This is mainly
5118 of interest to users of embedded R4xxx and R5xxx processors.
5120 * Higher serial baud rates
5122 GDB's serial code now allows you to specify baud rates 57600, 115200,
5123 230400, and 460800 baud. (Note that your host system may not be able
5124 to achieve all of these rates.)
5128 The i960 configuration now includes an initial implementation of a
5129 builtin simulator, contributed by Jim Wilson.
5132 *** Changes in GDB-4.17:
5134 * New native configurations
5136 Alpha GNU/Linux alpha*-*-linux*
5137 Unixware 2.x i[3456]86-unixware2*
5138 Irix 6.x mips*-sgi-irix6*
5139 PowerPC GNU/Linux powerpc-*-linux*
5140 PowerPC Solaris powerpcle-*-solaris*
5141 Sparc GNU/Linux sparc-*-linux*
5142 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5146 Argonaut Risc Chip (ARC) arc-*-*
5147 Hitachi H8/300S h8300*-*-*
5148 Matsushita MN10200 w/simulator mn10200-*-*
5149 Matsushita MN10300 w/simulator mn10300-*-*
5150 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5151 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5152 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5153 Mitsubishi D10V w/simulator d10v-*-*
5154 Mitsubishi M32R/D w/simulator m32r-*-elf*
5155 Tsqware Sparclet sparclet-*-*
5156 NEC V850 w/simulator v850-*-*
5158 * New debugging protocols
5160 ARM with RDI protocol arm*-*-*
5161 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5162 DDB and LSI variants of PMON protocol mips*-*-*
5163 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5164 PowerPC with SDS protocol powerpc{,le}-*-eabi
5165 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5169 All configurations can now understand and use the DWARF 2 debugging
5170 format. The choice is automatic, if the symbol file contains DWARF 2
5175 GDB now includes basic Java language support. This support is
5176 only useful with Java compilers that produce native machine code.
5178 * solib-absolute-prefix and solib-search-path
5180 For SunOS and SVR4 shared libraries, you may now set the prefix for
5181 loading absolute shared library symbol files, and the search path for
5182 locating non-absolute shared library symbol files.
5184 * Live range splitting
5186 GDB can now effectively debug code for which GCC has performed live
5187 range splitting as part of its optimization. See gdb/doc/LRS for
5188 more details on the expected format of the stabs information.
5192 GDB's support for the GNU Hurd, including thread debugging, has been
5193 updated to work with current versions of the Hurd.
5197 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5198 instruction set. ARM GDB automatically detects when Thumb
5199 instructions are in use, and adjusts disassembly and backtracing
5204 GDB's MIPS target configurations now handle the MIP16 16-bit
5209 GDB now includes support for overlays; if an executable has been
5210 linked such that multiple sections are based at the same address, GDB
5211 will decide which section to use for symbolic info. You can choose to
5212 control the decision manually, using overlay commands, or implement
5213 additional target-side support and use "overlay load-target" to bring
5214 in the overlay mapping. Do "help overlay" for more detail.
5218 The command "info symbol <address>" displays information about
5219 the symbol at the specified address.
5223 The standard remote protocol now includes an extension that allows
5224 asynchronous collection and display of trace data. This requires
5225 extensive support in the target-side debugging stub. Tracing mode
5226 includes a new interaction mode in GDB and new commands: see the
5227 file tracepoint.c for more details.
5231 Configurations for embedded MIPS now include a simulator contributed
5232 by Cygnus Solutions. The simulator supports the instruction sets
5233 of most MIPS variants.
5237 Sparc configurations may now include the ERC32 simulator contributed
5238 by the European Space Agency. The simulator is not built into
5239 Sparc targets by default; configure with --enable-sim to include it.
5243 For target configurations that may include multiple variants of a
5244 basic architecture (such as MIPS and SH), you may now set the
5245 architecture explicitly. "set arch" sets, "info arch" lists
5246 the possible architectures.
5248 *** Changes in GDB-4.16:
5250 * New native configurations
5252 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5253 M68K NetBSD m68k-*-netbsd*
5254 PowerPC AIX 4.x powerpc-*-aix*
5255 PowerPC MacOS powerpc-*-macos*
5256 PowerPC Windows NT powerpcle-*-cygwin32
5257 RS/6000 AIX 4.x rs6000-*-aix4*
5261 ARM with RDP protocol arm-*-*
5262 I960 with MON960 i960-*-coff
5263 MIPS VxWorks mips*-*-vxworks*
5264 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5265 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5267 Matra Sparclet sparclet-*-*
5271 The powerpc-eabi configuration now includes the PSIM simulator,
5272 contributed by Andrew Cagney, with assistance from Mike Meissner.
5273 PSIM is a very elaborate model of the PowerPC, including not only
5274 basic instruction set execution, but also details of execution unit
5275 performance and I/O hardware. See sim/ppc/README for more details.
5279 GDB now works with Solaris 2.5.
5281 * Windows 95/NT native
5283 GDB will now work as a native debugger on Windows 95 and Windows NT.
5284 To build it from source, you must use the "gnu-win32" environment,
5285 which uses a DLL to emulate enough of Unix to run the GNU tools.
5286 Further information, binaries, and sources are available at
5287 ftp.cygnus.com, under pub/gnu-win32.
5289 * dont-repeat command
5291 If a user-defined command includes the command `dont-repeat', then the
5292 command will not be repeated if the user just types return. This is
5293 useful if the command is time-consuming to run, so that accidental
5294 extra keystrokes don't run the same command many times.
5296 * Send break instead of ^C
5298 The standard remote protocol now includes an option to send a break
5299 rather than a ^C to the target in order to interrupt it. By default,
5300 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5302 * Remote protocol timeout
5304 The standard remote protocol includes a new variable `remotetimeout'
5305 that allows you to set the number of seconds before GDB gives up trying
5306 to read from the target. The default value is 2.
5308 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5310 By default GDB will automatically keep track of objects as they are
5311 loaded and unloaded by the dynamic linker. By using the command `set
5312 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5313 when shared library events occur, thus allowing you to set breakpoints
5314 in shared libraries which are explicitly loaded by the inferior.
5316 Note this feature does not work on hpux8. On hpux9 you must link
5317 /usr/lib/end.o into your program. This feature should work
5318 automatically on hpux10.
5320 * Irix 5.x hardware watchpoint support
5322 Irix 5 configurations now support the use of hardware watchpoints.
5324 * Mips protocol "SYN garbage limit"
5326 When debugging a Mips target using the `target mips' protocol, you
5327 may set the number of characters that GDB will ignore by setting
5328 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5329 every character. The default value is 1050.
5331 * Recording and replaying remote debug sessions
5333 If you set `remotelogfile' to the name of a file, gdb will write to it
5334 a recording of a remote debug session. This recording may then be
5335 replayed back to gdb using "gdbreplay". See gdbserver/README for
5336 details. This is useful when you have a problem with GDB while doing
5337 remote debugging; you can make a recording of the session and send it
5338 to someone else, who can then recreate the problem.
5340 * Speedups for remote debugging
5342 GDB includes speedups for downloading and stepping MIPS systems using
5343 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5344 and more efficient S-record downloading.
5346 * Memory use reductions and statistics collection
5348 GDB now uses less memory and reports statistics about memory usage.
5349 Try the `maint print statistics' command, for example.
5351 *** Changes in GDB-4.15:
5353 * Psymtabs for XCOFF
5355 The symbol reader for AIX GDB now uses partial symbol tables. This
5356 can greatly improve startup time, especially for large executables.
5358 * Remote targets use caching
5360 Remote targets now use a data cache to speed up communication with the
5361 remote side. The data cache could lead to incorrect results because
5362 it doesn't know about volatile variables, thus making it impossible to
5363 debug targets which use memory mapped I/O devices. `set remotecache
5364 off' turns the the data cache off.
5366 * Remote targets may have threads
5368 The standard remote protocol now includes support for multiple threads
5369 in the target system, using new protocol commands 'H' and 'T'. See
5370 gdb/remote.c for details.
5374 If GDB is configured with `--enable-netrom', then it will include
5375 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5376 acts as though it is a bank of ROM on the target board, but you can
5377 write into it over the network. GDB's support consists only of
5378 support for fast loading into the emulated ROM; to debug, you must use
5379 another protocol, such as standard remote protocol. The usual
5380 sequence is something like
5382 target nrom <netrom-hostname>
5384 target remote <netrom-hostname>:1235
5388 GDB now includes support for the Apple Macintosh, as a host only. It
5389 may be run as either an MPW tool or as a standalone application, and
5390 it can debug through the serial port. All the usual GDB commands are
5391 available, but to the target command, you must supply "serial" as the
5392 device type instead of "/dev/ttyXX". See mpw-README in the main
5393 directory for more information on how to build. The MPW configuration
5394 scripts */mpw-config.in support only a few targets, and only the
5395 mips-idt-ecoff target has been tested.
5399 GDB configuration now uses autoconf. This is not user-visible,
5400 but does simplify configuration and building.
5404 GDB now supports hpux10.
5406 *** Changes in GDB-4.14:
5408 * New native configurations
5410 x86 FreeBSD i[345]86-*-freebsd
5411 x86 NetBSD i[345]86-*-netbsd
5412 NS32k NetBSD ns32k-*-netbsd
5413 Sparc NetBSD sparc-*-netbsd
5417 A29K VxWorks a29k-*-vxworks
5418 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5419 CPU32 EST-300 emulator m68*-*-est*
5420 PowerPC ELF powerpc-*-elf
5423 * Alpha OSF/1 support for procfs
5425 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5426 possible to attach to running processes. As the mounting of the /proc
5427 filesystem is optional on the Alpha, GDB automatically determines
5428 the availability of /proc during startup. This can lead to problems
5429 if /proc is unmounted after GDB has been started.
5431 * Arguments to user-defined commands
5433 User commands may accept up to 10 arguments separated by whitespace.
5434 Arguments are accessed within the user command via $arg0..$arg9. A
5437 print $arg0 + $arg1 + $arg2
5439 To execute the command use:
5442 Defines the command "adder" which prints the sum of its three arguments.
5443 Note the arguments are text substitutions, so they may reference variables,
5444 use complex expressions, or even perform inferior function calls.
5446 * New `if' and `while' commands
5448 This makes it possible to write more sophisticated user-defined
5449 commands. Both commands take a single argument, which is the
5450 expression to evaluate, and must be followed by the commands to
5451 execute, one per line, if the expression is nonzero, the list being
5452 terminated by the word `end'. The `if' command list may include an
5453 `else' word, which causes the following commands to be executed only
5454 if the expression is zero.
5456 * Fortran source language mode
5458 GDB now includes partial support for Fortran 77. It will recognize
5459 Fortran programs and can evaluate a subset of Fortran expressions, but
5460 variables and functions may not be handled correctly. GDB will work
5461 with G77, but does not yet know much about symbols emitted by other
5464 * Better HPUX support
5466 Most debugging facilities now work on dynamic executables for HPPAs
5467 running hpux9 or later. You can attach to running dynamically linked
5468 processes, but by default the dynamic libraries will be read-only, so
5469 for instance you won't be able to put breakpoints in them. To change
5470 that behavior do the following before running the program:
5476 This will cause the libraries to be mapped private and read-write.
5477 To revert to the normal behavior, do this:
5483 You cannot set breakpoints or examine data in the library until after
5484 the library is loaded if the function/data symbols do not have
5487 GDB can now also read debug symbols produced by the HP C compiler on
5488 HPPAs (sorry, no C++, Fortran or 68k support).
5490 * Target byte order now dynamically selectable
5492 You can choose which byte order to use with a target system, via the
5493 commands "set endian big" and "set endian little", and you can see the
5494 current setting by using "show endian". You can also give the command
5495 "set endian auto", in which case GDB will use the byte order
5496 associated with the executable. Currently, only embedded MIPS
5497 configurations support dynamic selection of target byte order.
5499 * New DOS host serial code
5501 This version uses DPMI interrupts to handle buffered I/O, so you
5502 no longer need to run asynctsr when debugging boards connected to
5505 *** Changes in GDB-4.13:
5507 * New "complete" command
5509 This lists all the possible completions for the rest of the line, if it
5510 were to be given as a command itself. This is intended for use by emacs.
5512 * Trailing space optional in prompt
5514 "set prompt" no longer adds a space for you after the prompt you set. This
5515 allows you to set a prompt which ends in a space or one that does not.
5517 * Breakpoint hit counts
5519 "info break" now displays a count of the number of times the breakpoint
5520 has been hit. This is especially useful in conjunction with "ignore"; you
5521 can ignore a large number of breakpoint hits, look at the breakpoint info
5522 to see how many times the breakpoint was hit, then run again, ignoring one
5523 less than that number, and this will get you quickly to the last hit of
5526 * Ability to stop printing at NULL character
5528 "set print null-stop" will cause GDB to stop printing the characters of
5529 an array when the first NULL is encountered. This is useful when large
5530 arrays actually contain only short strings.
5532 * Shared library breakpoints
5534 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5535 breakpoints in shared libraries before the executable is run.
5537 * Hardware watchpoints
5539 There is a new hardware breakpoint for the watch command for sparclite
5540 targets. See gdb/sparclite/hw_breakpoint.note.
5542 Hardware watchpoints are also now supported under GNU/Linux.
5546 Annotations have been added. These are for use with graphical interfaces,
5547 and are still experimental. Currently only gdba.el uses these.
5549 * Improved Irix 5 support
5551 GDB now works properly with Irix 5.2.
5553 * Improved HPPA support
5555 GDB now works properly with the latest GCC and GAS.
5557 * New native configurations
5559 Sequent PTX4 i[34]86-sequent-ptx4
5560 HPPA running OSF/1 hppa*-*-osf*
5561 Atari TT running SVR4 m68*-*-sysv4*
5562 RS/6000 LynxOS rs6000-*-lynxos*
5566 OS/9000 i[34]86-*-os9k
5567 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5570 * Hitachi SH7000 and E7000-PC ICE support
5572 There is now support for communicating with the Hitachi E7000-PC ICE.
5573 This is available automatically when GDB is configured for the SH.
5577 As usual, a variety of small fixes and improvements, both generic
5578 and configuration-specific. See the ChangeLog for more detail.
5580 *** Changes in GDB-4.12:
5582 * Irix 5 is now supported
5586 GDB-4.12 on the HPPA has a number of changes which make it unable
5587 to debug the output from the currently released versions of GCC and
5588 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5589 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5590 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5593 *** Changes in GDB-4.11:
5595 * User visible changes:
5599 The "set remotedebug" option is now consistent between the mips remote
5600 target, remote targets using the gdb-specific protocol, UDI (AMD's
5601 debug protocol for the 29k) and the 88k bug monitor. It is now an
5602 integer specifying a debug level (normally 0 or 1, but 2 means more
5603 debugging info for the mips target).
5605 * DEC Alpha native support
5607 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5608 debug info, but GDB works fairly well with the DEC compiler and should
5609 work with a future GCC release. See the README file for a few
5610 Alpha-specific notes.
5612 * Preliminary thread implementation
5614 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5616 * LynxOS native and target support for 386
5618 This release has been hosted on LynxOS 2.2, and also can be configured
5619 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5622 * Improvements in C++ mangling/demangling.
5624 This release has much better g++ debugging, specifically in name
5625 mangling/demangling, virtual function calls, print virtual table,
5626 call methods, ...etc.
5628 *** Changes in GDB-4.10:
5630 * User visible changes:
5632 Remote debugging using the GDB-specific (`target remote') protocol now
5633 supports the `load' command. This is only useful if you have some
5634 other way of getting the stub to the target system, and you can put it
5635 somewhere in memory where it won't get clobbered by the download.
5637 Filename completion now works.
5639 When run under emacs mode, the "info line" command now causes the
5640 arrow to point to the line specified. Also, "info line" prints
5641 addresses in symbolic form (as well as hex).
5643 All vxworks based targets now support a user settable option, called
5644 vxworks-timeout. This option represents the number of seconds gdb
5645 should wait for responses to rpc's. You might want to use this if
5646 your vxworks target is, perhaps, a slow software simulator or happens
5647 to be on the far side of a thin network line.
5651 This release contains support for using a DEC alpha as a GDB host for
5652 cross debugging. Native alpha debugging is not supported yet.
5655 *** Changes in GDB-4.9:
5659 This is the first GDB release which is accompanied by a matching testsuite.
5660 The testsuite requires installation of dejagnu, which should be available
5661 via ftp from most sites that carry GNU software.
5665 'Cfront' style demangling has had its name changed to 'ARM' style, to
5666 emphasize that it was written from the specifications in the C++ Annotated
5667 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5668 disclaimers, it still generated too much confusion with users attempting to
5669 use gdb with AT&T cfront.
5673 GDB now uses a standard remote interface to a simulator library.
5674 So far, the library contains simulators for the Zilog Z8001/2, the
5675 Hitachi H8/300, H8/500 and Super-H.
5677 * New targets supported
5679 H8/300 simulator h8300-hitachi-hms or h8300hms
5680 H8/500 simulator h8500-hitachi-hms or h8500hms
5681 SH simulator sh-hitachi-hms or sh
5682 Z8000 simulator z8k-zilog-none or z8ksim
5683 IDT MIPS board over serial line mips-idt-ecoff
5685 Cross-debugging to GO32 targets is supported. It requires a custom
5686 version of the i386-stub.c module which is integrated with the
5687 GO32 memory extender.
5689 * New remote protocols
5691 MIPS remote debugging protocol.
5693 * New source languages supported
5695 This version includes preliminary support for Chill, a Pascal like language
5696 used by telecommunications companies. Chill support is also being integrated
5697 into the GNU compiler, but we don't know when it will be publically available.
5700 *** Changes in GDB-4.8:
5702 * HP Precision Architecture supported
5704 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5705 version of this support was available as a set of patches from the
5706 University of Utah. GDB does not support debugging of programs
5707 compiled with the HP compiler, because HP will not document their file
5708 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5709 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5711 Many problems in the preliminary version have been fixed.
5713 * Faster and better demangling
5715 We have improved template demangling and fixed numerous bugs in the GNU style
5716 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5717 character types (wchar_t) are now supported. Demangling of each symbol is now
5718 only done once, and is cached when the symbol table for a file is read in.
5719 This results in a small increase in memory usage for C programs, a moderate
5720 increase in memory usage for C++ programs, and a fantastic speedup in
5723 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5724 from the specifications in the Annotated Reference Manual, which AT&T's
5725 compiler does not actually implement.
5727 * G++ multiple inheritance compiler problem
5729 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5730 inheritance lattices was reworked to properly discover ambiguities. We
5731 recently found an example which causes this new algorithm to fail in a
5732 very subtle way, producing bad debug information for those classes.
5733 The file 'gcc.patch' (in this directory) can be applied to gcc to
5734 circumvent the problem. A future GCC release will contain a complete
5737 The previous G++ debug info problem (mentioned below for the gdb-4.7
5738 release) is fixed in gcc version 2.3.2.
5740 * Improved configure script
5742 The `configure' script will now attempt to guess your system type if
5743 you don't supply a host system type. The old scheme of supplying a
5744 host system triplet is preferable over using this. All the magic is
5745 done in the new `config.guess' script. Examine it for details.
5747 We have also brought our configure script much more in line with the FSF's
5748 version. It now supports the --with-xxx options. In particular,
5749 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5750 The resulting GDB will not be able to read arbitrary object file formats --
5751 only the format ``expected'' to be used on the configured target system.
5752 We hope to make this the default in a future release.
5754 * Documentation improvements
5756 There's new internal documentation on how to modify GDB, and how to
5757 produce clean changes to the code. We implore people to read it
5758 before submitting changes.
5760 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5761 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5762 `info' files are also provided. To build `info' files from scratch,
5763 you will need the latest `makeinfo' release, which will be available in
5764 a future texinfo-X.Y release.
5766 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5767 We're not sure exactly which versions have this problem, but it has
5768 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5769 or better. If that isn't possible, there is a patch in
5770 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5771 around this problem.
5775 GDB now supports array constants that can be used in expressions typed in by
5776 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5777 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5780 The new directory `gdb/sparclite' contains a program that demonstrates
5781 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5783 * New native hosts supported
5785 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5786 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5788 * New targets supported
5790 AMD 29k family via UDI a29k-amd-udi or udi29k
5792 * New file formats supported
5794 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5795 HPUX core files, and SCO 3.2v2 core files.
5799 Attaching to processes now works again; thanks for the many bug reports.
5801 We have also stomped on a bunch of core dumps caused by
5802 printf_filtered("%s") problems.
5804 We eliminated a copyright problem on the rpc and ptrace header files
5805 for VxWorks, which was discovered at the last minute during the 4.7
5806 release. You should now be able to build a VxWorks GDB.
5808 You can now interrupt gdb while an attached process is running. This
5809 will cause the attached process to stop, and give control back to GDB.
5811 We fixed problems caused by using too many file descriptors
5812 for reading symbols from object files and libraries. This was
5813 especially a problem for programs that used many (~100) shared
5816 The `step' command now only enters a subroutine if there is line number
5817 information for the subroutine. Otherwise it acts like the `next'
5818 command. Previously, `step' would enter subroutines if there was
5819 any debugging information about the routine. This avoids problems
5820 when using `cc -g1' on MIPS machines.
5822 * Internal improvements
5824 GDB's internal interfaces have been improved to make it easier to support
5825 debugging of multiple languages in the future.
5827 GDB now uses a common structure for symbol information internally.
5828 Minimal symbols (derived from linkage symbols in object files), partial
5829 symbols (from a quick scan of debug information), and full symbols
5830 contain a common subset of information, making it easier to write
5831 shared code that handles any of them.
5833 * New command line options
5835 We now accept --silent as an alias for --quiet.
5839 The memory-mapped-malloc library is now licensed under the GNU Library
5840 General Public License.
5842 *** Changes in GDB-4.7:
5844 * Host/native/target split
5846 GDB has had some major internal surgery to untangle the support for
5847 hosts and remote targets. Now, when you configure GDB for a remote
5848 target, it will no longer load in all of the support for debugging
5849 local programs on the host. When fully completed and tested, this will
5850 ensure that arbitrary host/target combinations are possible.
5852 The primary conceptual shift is to separate the non-portable code in
5853 GDB into three categories. Host specific code is required any time GDB
5854 is compiled on that host, regardless of the target. Target specific
5855 code relates to the peculiarities of the target, but can be compiled on
5856 any host. Native specific code is everything else: it can only be
5857 built when the host and target are the same system. Child process
5858 handling and core file support are two common `native' examples.
5860 GDB's use of /proc for controlling Unix child processes is now cleaner.
5861 It has been split out into a single module under the `target_ops' vector,
5862 plus two native-dependent functions for each system that uses /proc.
5864 * New hosts supported
5866 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5867 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5868 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5870 * New targets supported
5872 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5873 68030 and CPU32 m68030-*-*, m68332-*-*
5875 * New native hosts supported
5877 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5878 (386bsd is not well tested yet)
5879 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5881 * New file formats supported
5883 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5884 supports reading of `a.out.adobe' object files, which are an a.out
5885 format extended with minimal information about multiple sections.
5889 `show copying' is the same as the old `info copying'.
5890 `show warranty' is the same as `info warrantee'.
5891 These were renamed for consistency. The old commands continue to work.
5893 `info handle' is a new alias for `info signals'.
5895 You can now define pre-command hooks, which attach arbitrary command
5896 scripts to any command. The commands in the hook will be executed
5897 prior to the user's command. You can also create a hook which will be
5898 executed whenever the program stops. See gdb.texinfo.
5902 We now deal with Cfront style name mangling, and can even extract type
5903 info from mangled symbols. GDB can automatically figure out which
5904 symbol mangling style your C++ compiler uses.
5906 Calling of methods and virtual functions has been improved as well.
5910 The crash that occured when debugging Sun Ansi-C compiled binaries is
5911 fixed. This was due to mishandling of the extra N_SO stabs output
5914 We also finally got Ultrix 4.2 running in house, and fixed core file
5915 support, with help from a dozen people on the net.
5917 John M. Farrell discovered that the reason that single-stepping was so
5918 slow on all of the Mips based platforms (primarily SGI and DEC) was
5919 that we were trying to demangle and lookup a symbol used for internal
5920 purposes on every instruction that was being stepped through. Changing
5921 the name of that symbol so that it couldn't be mistaken for a C++
5922 mangled symbol sped things up a great deal.
5924 Rich Pixley sped up symbol lookups in general by getting much smarter
5925 about when C++ symbol mangling is necessary. This should make symbol
5926 completion (TAB on the command line) much faster. It's not as fast as
5927 we'd like, but it's significantly faster than gdb-4.6.
5931 A new user controllable variable 'call_scratch_address' can
5932 specify the location of a scratch area to be used when GDB
5933 calls a function in the target. This is necessary because the
5934 usual method of putting the scratch area on the stack does not work
5935 in systems that have separate instruction and data spaces.
5937 We integrated changes to support the 29k UDI (Universal Debugger
5938 Interface), but discovered at the last minute that we didn't have all
5939 of the appropriate copyright paperwork. We are working with AMD to
5940 resolve this, and hope to have it available soon.
5944 We have sped up the remote serial line protocol, especially for targets
5945 with lots of registers. It now supports a new `expedited status' ('T')
5946 message which can be used in place of the existing 'S' status message.
5947 This allows the remote stub to send only the registers that GDB
5948 needs to make a quick decision about single-stepping or conditional
5949 breakpoints, eliminating the need to fetch the entire register set for
5950 each instruction being stepped through.
5952 The GDB remote serial protocol now implements a write-through cache for
5953 registers, only re-reading the registers if the target has run.
5955 There is also a new remote serial stub for SPARC processors. You can
5956 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5957 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5958 processor with a serial port.
5962 Configure.in files have become much easier to read and modify. A new
5963 `table driven' format makes it more obvious what configurations are
5964 supported, and what files each one uses.
5968 There is a new opcodes library which will eventually contain all of the
5969 disassembly routines and opcode tables. At present, it only contains
5970 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5971 disassembler (binutils/objdump) to share these routines.
5973 The libiberty library is now copylefted under the GNU Library General
5974 Public License. This allows more liberal use, and was done so libg++
5975 can use it. This makes no difference to GDB, since the Library License
5976 grants all the rights from the General Public License.
5980 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5981 reference to the stabs symbol info used by the debugger. It is (as far
5982 as we know) the only published document on this fascinating topic. We
5983 encourage you to read it, compare it to the stabs information on your
5984 system, and send improvements on the document in general (to
5985 bug-gdb@prep.ai.mit.edu).
5987 And, of course, many bugs have been fixed.
5990 *** Changes in GDB-4.6:
5992 * Better support for C++ function names
5994 GDB now accepts as input the "demangled form" of C++ overloaded function
5995 names and member function names, and can do command completion on such names
5996 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5997 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5998 Make use of command completion, it is your friend.
6000 GDB also now accepts a variety of C++ mangled symbol formats. They are
6001 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6002 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6003 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6004 for the list of formats.
6006 * G++ symbol mangling problem
6008 Recent versions of gcc have a bug in how they emit debugging information for
6009 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6010 directory) can be applied to gcc to fix the problem. Alternatively, if you
6011 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6012 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6013 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6016 * New 'maintenance' command
6018 All of the commands related to hacking GDB internals have been moved out of
6019 the main command set, and now live behind the 'maintenance' command. This
6020 can also be abbreviated as 'mt'. The following changes were made:
6022 dump-me -> maintenance dump-me
6023 info all-breakpoints -> maintenance info breakpoints
6024 printmsyms -> maintenance print msyms
6025 printobjfiles -> maintenance print objfiles
6026 printpsyms -> maintenance print psymbols
6027 printsyms -> maintenance print symbols
6029 The following commands are new:
6031 maintenance demangle Call internal GDB demangler routine to
6032 demangle a C++ link name and prints the result.
6033 maintenance print type Print a type chain for a given symbol
6035 * Change to .gdbinit file processing
6037 We now read the $HOME/.gdbinit file before processing the argv arguments
6038 (e.g. reading symbol files or core files). This allows global parameters to
6039 be set, which will apply during the symbol reading. The ./.gdbinit is still
6040 read after argv processing.
6042 * New hosts supported
6044 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6046 GNU/Linux support i386-unknown-linux or linux
6048 We are also including code to support the HP/PA running BSD and HPUX. This
6049 is almost guaranteed not to work, as we didn't have time to test or build it
6050 for this release. We are including it so that the more adventurous (or
6051 masochistic) of you can play with it. We also had major problems with the
6052 fact that the compiler that we got from HP doesn't support the -g option.
6055 * New targets supported
6057 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6059 * More smarts about finding #include files
6061 GDB now remembers the compilation directory for all include files, and for
6062 all files from which C is generated (like yacc and lex sources). This
6063 greatly improves GDB's ability to find yacc/lex sources, and include files,
6064 especially if you are debugging your program from a directory different from
6065 the one that contains your sources.
6067 We also fixed a bug which caused difficulty with listing and setting
6068 breakpoints in include files which contain C code. (In the past, you had to
6069 try twice in order to list an include file that you hadn't looked at before.)
6071 * Interesting infernals change
6073 GDB now deals with arbitrary numbers of sections, where the symbols for each
6074 section must be relocated relative to that section's landing place in the
6075 target's address space. This work was needed to support ELF with embedded
6076 stabs used by Solaris-2.0.
6078 * Bug fixes (of course!)
6080 There have been loads of fixes for the following things:
6081 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6082 i960, stabs, DOS(GO32), procfs, etc...
6084 See the ChangeLog for details.
6086 *** Changes in GDB-4.5:
6088 * New machines supported (host and target)
6090 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6092 SGI Irix-4.x mips-sgi-irix4 or iris4
6094 * New malloc package
6096 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6097 Mmalloc is capable of handling mutiple heaps of memory. It is also
6098 capable of saving a heap to a file, and then mapping it back in later.
6099 This can be used to greatly speedup the startup of GDB by using a
6100 pre-parsed symbol table which lives in a mmalloc managed heap. For
6101 more details, please read mmalloc/mmalloc.texi.
6105 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6106 'help info proc' for details.
6108 * MIPS ecoff symbol table format
6110 The code that reads MIPS symbol table format is now supported on all hosts.
6111 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6114 * File name changes for MS-DOS
6116 Many files in the config directories have been renamed to make it easier to
6117 support GDB on MS-DOSe systems (which have very restrictive file name
6118 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6119 environment) is close to working but has some remaining problems. Note
6120 that debugging of DOS programs is not supported, due to limitations
6121 in the ``operating system'', but it can be used to host cross-debugging.
6123 * Cross byte order fixes
6125 Many fixes have been made to support cross debugging of Sparc and MIPS
6126 targets from hosts whose byte order differs.
6128 * New -mapped and -readnow options
6130 If memory-mapped files are available on your system through the 'mmap'
6131 system call, you can use the -mapped option on the `file' or
6132 `symbol-file' commands to cause GDB to write the symbols from your
6133 program into a reusable file. If the program you are debugging is
6134 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6135 Future GDB debugging sessions will notice the presence of this file,
6136 and will quickly map in symbol information from it, rather than reading
6137 the symbol table from the executable program. Using the '-mapped'
6138 option in a GDB `file' or `symbol-file' command has the same effect as
6139 starting GDB with the '-mapped' command-line option.
6141 You can cause GDB to read the entire symbol table immediately by using
6142 the '-readnow' option with any of the commands that load symbol table
6143 information (or on the GDB command line). This makes the command
6144 slower, but makes future operations faster.
6146 The -mapped and -readnow options are typically combined in order to
6147 build a `fred.syms' file that contains complete symbol information.
6148 A simple GDB invocation to do nothing but build a `.syms' file for future
6151 gdb -batch -nx -mapped -readnow programname
6153 The `.syms' file is specific to the host machine on which GDB is run.
6154 It holds an exact image of GDB's internal symbol table. It cannot be
6155 shared across multiple host platforms.
6157 * longjmp() handling
6159 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6160 siglongjmp() without losing control. This feature has not yet been ported to
6161 all systems. It currently works on many 386 platforms, all MIPS-based
6162 platforms (SGI, DECstation, etc), and Sun3/4.
6166 Preliminary work has been put in to support the new Solaris OS from Sun. At
6167 this time, it can control and debug processes, but it is not capable of
6172 As always, many many bug fixes. The major areas were with g++, and mipsread.
6173 People using the MIPS-based platforms should experience fewer mysterious
6174 crashes and trashed symbol tables.
6176 *** Changes in GDB-4.4:
6178 * New machines supported (host and target)
6180 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6182 BSD Reno on Vax vax-dec-bsd
6183 Ultrix on Vax vax-dec-ultrix
6185 * New machines supported (target)
6187 AMD 29000 embedded, using EBMON a29k-none-none
6191 GDB continues to improve its handling of C++. `References' work better.
6192 The demangler has also been improved, and now deals with symbols mangled as
6193 per the Annotated C++ Reference Guide.
6195 GDB also now handles `stabs' symbol information embedded in MIPS
6196 `ecoff' symbol tables. Since the ecoff format was not easily
6197 extensible to handle new languages such as C++, this appeared to be a
6198 good way to put C++ debugging info into MIPS binaries. This option
6199 will be supported in the GNU C compiler, version 2, when it is
6202 * New features for SVR4
6204 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6205 shared libraries. Debugging dynamically linked programs should present
6206 only minor differences from debugging statically linked programs.
6208 The `info proc' command will print out information about any process
6209 on an SVR4 system (including the one you are debugging). At the moment,
6210 it prints the address mappings of the process.
6212 If you bring up GDB on another SVR4 system, please send mail to
6213 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6215 * Better dynamic linking support in SunOS
6217 Reading symbols from shared libraries which contain debugging symbols
6218 now works properly. However, there remain issues such as automatic
6219 skipping of `transfer vector' code during function calls, which
6220 make it harder to debug code in a shared library, than to debug the
6221 same code linked statically.
6225 GDB is now using the latest `getopt' routines from the FSF. This
6226 version accepts the -- prefix for options with long names. GDB will
6227 continue to accept the old forms (-option and +option) as well.
6228 Various single letter abbreviations for options have been explicity
6229 added to the option table so that they won't get overshadowed in the
6230 future by other options that begin with the same letter.
6234 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6235 Many assorted bugs have been handled. Many more remain to be handled.
6236 See the various ChangeLog files (primarily in gdb and bfd) for details.
6239 *** Changes in GDB-4.3:
6241 * New machines supported (host and target)
6243 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6244 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6245 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6247 * Almost SCO Unix support
6249 We had hoped to support:
6250 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6251 (except for core file support), but we discovered very late in the release
6252 that it has problems with process groups that render gdb unusable. Sorry
6253 about that. I encourage people to fix it and post the fixes.
6255 * Preliminary ELF and DWARF support
6257 GDB can read ELF object files on System V Release 4, and can handle
6258 debugging records for C, in DWARF format, in ELF files. This support
6259 is preliminary. If you bring up GDB on another SVR4 system, please
6260 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6265 GDB now uses the latest `readline' library. One user-visible change
6266 is that two tabs will list possible command completions, which previously
6267 required typing M-? (meta-question mark, or ESC ?).
6271 The `stepi' bug that many of you noticed has been squashed.
6272 Many bugs in C++ have been handled. Many more remain to be handled.
6273 See the various ChangeLog files (primarily in gdb and bfd) for details.
6275 * State of the MIPS world (in case you wondered):
6277 GDB can understand the symbol tables emitted by the compilers
6278 supplied by most vendors of MIPS-based machines, including DEC. These
6279 symbol tables are in a format that essentially nobody else uses.
6281 Some versions of gcc come with an assembler post-processor called
6282 mips-tfile. This program is required if you want to do source-level
6283 debugging of gcc-compiled programs. I believe FSF does not ship
6284 mips-tfile with gcc version 1, but it will eventually come with gcc
6287 Debugging of g++ output remains a problem. g++ version 1.xx does not
6288 really support it at all. (If you're lucky, you should be able to get
6289 line numbers and stack traces to work, but no parameters or local
6290 variables.) With some work it should be possible to improve the
6293 When gcc version 2 is released, you will have somewhat better luck.
6294 However, even then you will get confusing results for inheritance and
6297 We will eventually provide full debugging of g++ output on
6298 DECstations. This will probably involve some kind of stabs-in-ecoff
6299 encapulation, but the details have not been worked out yet.
6302 *** Changes in GDB-4.2:
6304 * Improved configuration
6306 Only one copy of `configure' exists now, and it is not self-modifying.
6307 Porting BFD is simpler.
6311 The `step' and `next' commands now only stop at the first instruction
6312 of a source line. This prevents the multiple stops that used to occur
6313 in switch statements, for-loops, etc. `Step' continues to stop if a
6314 function that has debugging information is called within the line.
6318 Lots of small bugs fixed. More remain.
6320 * New host supported (not target)
6322 Intel 386 PC clone running Mach i386-none-mach
6325 *** Changes in GDB-4.1:
6327 * Multiple source language support
6329 GDB now has internal scaffolding to handle several source languages.
6330 It determines the type of each source file from its filename extension,
6331 and will switch expression parsing and number formatting to match the
6332 language of the function in the currently selected stack frame.
6333 You can also specifically set the language to be used, with
6334 `set language c' or `set language modula-2'.
6338 GDB now has preliminary support for the GNU Modula-2 compiler,
6339 currently under development at the State University of New York at
6340 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6341 continue through the fall of 1991 and into 1992.
6343 Other Modula-2 compilers are currently not supported, and attempting to
6344 debug programs compiled with them will likely result in an error as the
6345 symbol table is read. Feel free to work on it, though!
6347 There are hooks in GDB for strict type checking and range checking,
6348 in the `Modula-2 philosophy', but they do not currently work.
6352 GDB can now write to executable and core files (e.g. patch
6353 a variable's value). You must turn this switch on, specify
6354 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6355 by assigning a new value to a variable. Modifications take
6358 * Automatic SunOS shared library reading
6360 When you run your program, GDB automatically determines where its
6361 shared libraries (if any) have been loaded, and reads their symbols.
6362 The `share' command is no longer needed. This also works when
6363 examining core files.
6367 You can specify the number of lines that the `list' command shows.
6370 * New machines supported (host and target)
6372 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6373 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6374 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6376 * New hosts supported (not targets)
6378 IBM RT/PC: romp-ibm-aix or rtpc
6380 * New targets supported (not hosts)
6382 AMD 29000 embedded with COFF a29k-none-coff
6383 AMD 29000 embedded with a.out a29k-none-aout
6384 Ultracomputer remote kernel debug a29k-nyu-kern
6386 * New remote interfaces
6392 *** Changes in GDB-4.0:
6396 Wide output is wrapped at good places to make the output more readable.
6398 Gdb now supports cross-debugging from a host machine of one type to a
6399 target machine of another type. Communication with the target system
6400 is over serial lines. The ``target'' command handles connecting to the
6401 remote system; the ``load'' command will download a program into the
6402 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6403 also supports debugging of realtime processes running under VxWorks,
6404 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6405 stub on the target system.
6407 New CPUs supported include the AMD 29000 and Intel 960.
6409 GDB now reads object files and symbol tables via a ``binary file''
6410 library, which allows a single copy of GDB to debug programs of multiple
6411 object file types such as a.out and coff.
6413 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6414 refcard.dvi and refcard.ps are available to format it).
6417 * Control-Variable user interface simplified
6419 All variables that control the operation of the debugger can be set
6420 by the ``set'' command, and displayed by the ``show'' command.
6422 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6423 ``Show prompt'' produces the response:
6424 Gdb's prompt is new-gdb=>.
6426 What follows are the NEW set commands. The command ``help set'' will
6427 print a complete list of old and new set commands. ``help set FOO''
6428 will give a longer description of the variable FOO. ``show'' will show
6429 all of the variable descriptions and their current settings.
6431 confirm on/off: Enables warning questions for operations that are
6432 hard to recover from, e.g. rerunning the program while
6433 it is already running. Default is ON.
6435 editing on/off: Enables EMACS style command line editing
6436 of input. Previous lines can be recalled with
6437 control-P, the current line can be edited with control-B,
6438 you can search for commands with control-R, etc.
6441 history filename NAME: NAME is where the gdb command history
6442 will be stored. The default is .gdb_history,
6443 or the value of the environment variable
6446 history size N: The size, in commands, of the command history. The
6447 default is 256, or the value of the environment variable
6450 history save on/off: If this value is set to ON, the history file will
6451 be saved after exiting gdb. If set to OFF, the
6452 file will not be saved. The default is OFF.
6454 history expansion on/off: If this value is set to ON, then csh-like
6455 history expansion will be performed on
6456 command line input. The default is OFF.
6458 radix N: Sets the default radix for input and output. It can be set
6459 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6460 in the current radix, so "set radix 10" is always a no-op.
6462 height N: This integer value is the number of lines on a page. Default
6463 is 24, the current `stty rows'' setting, or the ``li#''
6464 setting from the termcap entry matching the environment
6467 width N: This integer value is the number of characters on a line.
6468 Default is 80, the current `stty cols'' setting, or the ``co#''
6469 setting from the termcap entry matching the environment
6472 Note: ``set screensize'' is obsolete. Use ``set height'' and
6473 ``set width'' instead.
6475 print address on/off: Print memory addresses in various command displays,
6476 such as stack traces and structure values. Gdb looks
6477 more ``symbolic'' if you turn this off; it looks more
6478 ``machine level'' with it on. Default is ON.
6480 print array on/off: Prettyprint arrays. New convenient format! Default
6483 print demangle on/off: Print C++ symbols in "source" form if on,
6486 print asm-demangle on/off: Same, for assembler level printouts
6489 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6492 * Support for Epoch Environment.
6494 The epoch environment is a version of Emacs v18 with windowing. One
6495 new command, ``inspect'', is identical to ``print'', except that if you
6496 are running in the epoch environment, the value is printed in its own
6500 * Support for Shared Libraries
6502 GDB can now debug programs and core files that use SunOS shared libraries.
6503 Symbols from a shared library cannot be referenced
6504 before the shared library has been linked with the program (this
6505 happens after you type ``run'' and before the function main() is entered).
6506 At any time after this linking (including when examining core files
6507 from dynamically linked programs), gdb reads the symbols from each
6508 shared library when you type the ``sharedlibrary'' command.
6509 It can be abbreviated ``share''.
6511 sharedlibrary REGEXP: Load shared object library symbols for files
6512 matching a unix regular expression. No argument
6513 indicates to load symbols for all shared libraries.
6515 info sharedlibrary: Status of loaded shared libraries.
6520 A watchpoint stops execution of a program whenever the value of an
6521 expression changes. Checking for this slows down execution
6522 tremendously whenever you are in the scope of the expression, but is
6523 quite useful for catching tough ``bit-spreader'' or pointer misuse
6524 problems. Some machines such as the 386 have hardware for doing this
6525 more quickly, and future versions of gdb will use this hardware.
6527 watch EXP: Set a watchpoint (breakpoint) for an expression.
6529 info watchpoints: Information about your watchpoints.
6531 delete N: Deletes watchpoint number N (same as breakpoints).
6532 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6533 enable N: Re-enables watchpoint number N (same as breakpoints).
6536 * C++ multiple inheritance
6538 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6541 * C++ exception handling
6543 Gdb now supports limited C++ exception handling. Besides the existing
6544 ability to breakpoint on an exception handler, gdb can breakpoint on
6545 the raising of an exception (before the stack is peeled back to the
6548 catch FOO: If there is a FOO exception handler in the dynamic scope,
6549 set a breakpoint to catch exceptions which may be raised there.
6550 Multiple exceptions (``catch foo bar baz'') may be caught.
6552 info catch: Lists all exceptions which may be caught in the
6553 current stack frame.
6556 * Minor command changes
6558 The command ``call func (arg, arg, ...)'' now acts like the print
6559 command, except it does not print or save a value if the function's result
6560 is void. This is similar to dbx usage.
6562 The ``up'' and ``down'' commands now always print the frame they end up
6563 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6564 frames without printing.
6566 * New directory command
6568 'dir' now adds directories to the FRONT of the source search path.
6569 The path starts off empty. Source files that contain debug information
6570 about the directory in which they were compiled can be found even
6571 with an empty path; Sun CC and GCC include this information. If GDB can't
6572 find your source file in the current directory, type "dir .".
6574 * Configuring GDB for compilation
6576 For normal use, type ``./configure host''. See README or gdb.texinfo
6579 GDB now handles cross debugging. If you are remotely debugging between
6580 two different machines, type ``./configure host -target=targ''.
6581 Host is the machine where GDB will run; targ is the machine
6582 where the program that you are debugging will run.