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 * Support for Java programs compiled with gcj has been removed.
22 Synopsys ARC arc*-*-elf32
24 *** Changes in GDB 7.12
26 * GDB and GDBserver now build with a C++ compiler by default.
28 The --enable-build-with-cxx configure option is now enabled by
29 default. One must now explicitly configure with
30 --disable-build-with-cxx in order to build with a C compiler. This
31 option will be removed in a future release.
33 * GDBserver now supports recording btrace without maintaining an active
36 * GDB now supports a negative repeat count in the 'x' command to examine
37 memory backward from the given address. For example:
40 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
41 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
42 (gdb) x/-5i 0x0000000000400580
43 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
44 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
45 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
46 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
47 0x40057b <main(int, char**)+25>:
48 callq 0x400536 <Func1(int, char const*)>
50 * Fortran: Support structures with fields of dynamic types and
51 arrays of dynamic types.
53 * GDB now supports multibit bitfields and enums in target register
56 * New Python-based convenience function $_as_string(val), which returns
57 the textual representation of a value. This function is especially
58 useful to obtain the text label of an enum value.
60 * Intel MPX bound violation handling.
62 Segmentation faults caused by a Intel MPX boundary violation
63 now display the kind of violation (upper or lower), the memory
64 address accessed and the memory bounds, along with the usual
65 signal received and code location.
69 Program received signal SIGSEGV, Segmentation fault
70 Upper bound violation while accessing address 0x7fffffffc3b3
71 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
72 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
74 * Rust language support.
75 GDB now supports debugging programs written in the Rust programming
76 language. See https://www.rust-lang.org/ for more information about
79 * Support for running interpreters on specified input/output devices
81 GDB now supports a new mechanism that allows frontends to provide
82 fully featured GDB console views, as a better alternative to
83 building such views on top of the "-interpreter-exec console"
84 command. See the new "new-ui" command below. With that command,
85 frontends can now start GDB in the traditional command-line mode
86 running in an embedded terminal emulator widget, and create a
87 separate MI interpreter running on a specified i/o device. In this
88 way, GDB handles line editing, history, tab completion, etc. in the
89 console all by itself, and the GUI uses the separate MI interpreter
90 for its own control and synchronization, invisible to the command
93 * The "catch syscall" command catches groups of related syscalls.
95 The "catch syscall" command now supports catching a group of related
96 syscalls using the 'group:' or 'g:' prefix.
101 skip -gfile file-glob-pattern
102 skip -function function
103 skip -rfunction regular-expression
104 A generalized form of the skip command, with new support for
105 glob-style file names and regular expressions for function names.
106 Additionally, a file spec and a function spec may now be combined.
108 maint info line-table REGEXP
109 Display the contents of GDB's internal line table data struture.
112 Run any GDB unit tests that were compiled in.
115 Start a new user interface instance running INTERP as interpreter,
116 using the TTY file for input/output.
120 ** gdb.Breakpoint objects have a new attribute "pending", which
121 indicates whether the breakpoint is pending.
122 ** Three new breakpoint-related events have been added:
123 gdb.breakpoint_created, gdb.breakpoint_modified, and
124 gdb.breakpoint_deleted.
127 Signal ("set") the given MS-Windows event object. This is used in
128 conjunction with the Windows JIT debugging (AeDebug) support, where
129 the OS suspends a crashing process until a debugger can attach to
130 it. Resuming the crashing process, in order to debug it, is done by
133 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
134 was added in GDBserver, including JIT compiling fast tracepoint's
135 conditional expression bytecode into native code.
137 * Support for various remote target protocols and ROM monitors has
140 target m32rsdi Remote M32R debugging over SDI
141 target mips MIPS remote debugging protocol
142 target pmon PMON ROM monitor
143 target ddb NEC's DDB variant of PMON for Vr4300
144 target rockhopper NEC RockHopper variant of PMON
145 target lsi LSI variant of PMO
147 * Support for tracepoints and fast tracepoints on powerpc-linux,
148 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
149 including JIT compiling fast tracepoint's conditional expression
150 bytecode into native code.
152 * MI async record =record-started now includes the method and format used for
153 recording. For example:
155 =record-started,thread-group="i1",method="btrace",format="bts"
157 * MI async record =thread-selected now includes the frame field. For example:
159 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
163 Andes NDS32 nds32*-*-elf
165 *** Changes in GDB 7.11
167 * GDB now supports debugging kernel-based threads on FreeBSD.
169 * Per-inferior thread numbers
171 Thread numbers are now per inferior instead of global. If you're
172 debugging multiple inferiors, GDB displays thread IDs using a
173 qualified INF_NUM.THR_NUM form. For example:
177 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
178 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
179 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
180 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
182 As consequence, thread numbers as visible in the $_thread
183 convenience variable and in Python's InferiorThread.num attribute
184 are no longer unique between inferiors.
186 GDB now maintains a second thread ID per thread, referred to as the
187 global thread ID, which is the new equivalent of thread numbers in
188 previous releases. See also $_gthread below.
190 For backwards compatibility, MI's thread IDs always refer to global
193 * Commands that accept thread IDs now accept the qualified
194 INF_NUM.THR_NUM form as well. For example:
197 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
200 * In commands that accept a list of thread IDs, you can now refer to
201 all threads of an inferior using a star wildcard. GDB accepts
202 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
203 refer to all threads of the current inferior. For example, "info
206 * You can use "info threads -gid" to display the global thread ID of
209 * The new convenience variable $_gthread holds the global number of
212 * The new convenience variable $_inferior holds the number of the
215 * GDB now displays the ID and name of the thread that hit a breakpoint
216 or received a signal, if your program is multi-threaded. For
219 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
220 Thread 1 "main" received signal SIGINT, Interrupt.
222 * Record btrace now supports non-stop mode.
224 * Support for tracepoints on aarch64-linux was added in GDBserver.
226 * The 'record instruction-history' command now indicates speculative execution
227 when using the Intel Processor Trace recording format.
229 * GDB now allows users to specify explicit locations, bypassing
230 the linespec parser. This feature is also available to GDB/MI
233 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
234 GDB now is able to debug both AArch64 applications and ARM applications
237 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
238 including JIT compiling fast tracepoint's conditional expression bytecode
241 * GDB now supports displaced stepping on AArch64 GNU/Linux.
243 * "info threads", "info inferiors", "info display", "info checkpoints"
244 and "maint info program-spaces" now list the corresponding items in
245 ascending ID order, for consistency with all other "info" commands.
247 * In Ada, the overloads selection menu has been enhanced to display the
248 parameter types and the return types for the matching overloaded subprograms.
252 maint set target-non-stop (on|off|auto)
253 maint show target-non-stop
254 Control whether GDB targets always operate in non-stop mode even if
255 "set non-stop" is "off". The default is "auto", meaning non-stop
256 mode is enabled if supported by the target.
258 maint set bfd-sharing
259 maint show bfd-sharing
260 Control the reuse of bfd objects.
264 Control display of debugging info regarding bfd caching.
268 Control display of debugging info regarding FreeBSD threads.
270 set remote multiprocess-extensions-packet
271 show remote multiprocess-extensions-packet
272 Set/show the use of the remote protocol multiprocess extensions.
274 set remote thread-events
275 show remote thread-events
276 Set/show the use of thread create/exit events.
278 set ada print-signatures on|off
279 show ada print-signatures"
280 Control whether parameter types and return types are displayed in overloads
281 selection menus. It is activaled (@code{on}) by default.
285 Controls the maximum size of memory, in bytes, that GDB will
286 allocate for value contents. Prevents incorrect programs from
287 causing GDB to allocate overly large buffers. Default is 64k.
289 * The "disassemble" command accepts a new modifier: /s.
290 It prints mixed source+disassembly like /m with two differences:
291 - disassembled instructions are now printed in program order, and
292 - and source for all relevant files is now printed.
293 The "/m" option is now considered deprecated: its "source-centric"
294 output hasn't proved useful in practice.
296 * The "record instruction-history" command accepts a new modifier: /s.
297 It behaves exactly like /m and prints mixed source+disassembly.
299 * The "set scheduler-locking" command supports a new mode "replay".
300 It behaves like "off" in record mode and like "on" in replay mode.
302 * Support for various ROM monitors has been removed:
304 target dbug dBUG ROM monitor for Motorola ColdFire
305 target picobug Motorola picobug monitor
306 target dink32 DINK32 ROM monitor for PowerPC
307 target m32r Renesas M32R/D ROM monitor
308 target mon2000 mon2000 ROM monitor
309 target ppcbug PPCBUG ROM monitor for PowerPC
311 * Support for reading/writing memory and extracting values on architectures
312 whose memory is addressable in units of any integral multiple of 8 bits.
317 Indicates that an exec system call was executed.
319 exec-events feature in qSupported
320 The qSupported packet allows GDB to request support for exec
321 events using the new 'gdbfeature' exec-event, and the qSupported
322 response can contain the corresponding 'stubfeature'. Set and
323 show commands can be used to display whether these features are enabled.
326 Equivalent to interrupting with the ^C character, but works in
329 thread created stop reason (T05 create:...)
330 Indicates that the thread was just created and is stopped at entry.
332 thread exit stop reply (w exitcode;tid)
333 Indicates that the thread has terminated.
336 Enables/disables thread create and exit event reporting. For
337 example, this is used in non-stop mode when GDB stops a set of
338 threads and synchronously waits for the their corresponding stop
339 replies. Without exit events, if one of the threads exits, GDB
340 would hang forever not knowing that it should no longer expect a
341 stop for that same thread.
344 Indicates that there are no resumed threads left in the target (all
345 threads are stopped). The remote stub reports support for this stop
346 reply to GDB's qSupported query.
349 Enables/disables catching syscalls from the inferior process.
350 The remote stub reports support for this packet to GDB's qSupported query.
352 syscall_entry stop reason
353 Indicates that a syscall was just called.
355 syscall_return stop reason
356 Indicates that a syscall just returned.
358 * Extended-remote exec events
360 ** GDB now has support for exec events on extended-remote Linux targets.
361 For such targets with Linux kernels 2.5.46 and later, this enables
362 follow-exec-mode and exec catchpoints.
364 set remote exec-event-feature-packet
365 show remote exec-event-feature-packet
366 Set/show the use of the remote exec event feature.
368 * Thread names in remote protocol
370 The reply to qXfer:threads:read may now include a name attribute for each
373 * Target remote mode fork and exec events
375 ** GDB now has support for fork and exec events on target remote mode
376 Linux targets. For such targets with Linux kernels 2.5.46 and later,
377 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
378 fork and exec catchpoints.
380 * Remote syscall events
382 ** GDB now has support for catch syscall on remote Linux targets,
383 currently enabled on x86/x86_64 architectures.
385 set remote catch-syscall-packet
386 show remote catch-syscall-packet
387 Set/show the use of the remote catch syscall feature.
391 ** The -var-set-format command now accepts the zero-hexadecimal
392 format. It outputs data in hexadecimal format with zero-padding on the
397 ** gdb.InferiorThread objects have a new attribute "global_num",
398 which refers to the thread's global thread ID. The existing
399 "num" attribute now refers to the thread's per-inferior number.
400 See "Per-inferior thread numbers" above.
401 ** gdb.InferiorThread objects have a new attribute "inferior", which
402 is the Inferior object the thread belongs to.
404 *** Changes in GDB 7.10
406 * Support for process record-replay and reverse debugging on aarch64*-linux*
407 targets has been added. GDB now supports recording of A64 instruction set
408 including advance SIMD instructions.
410 * Support for Sun's version of the "stabs" debug file format has been removed.
412 * GDB now honors the content of the file /proc/PID/coredump_filter
413 (PID is the process ID) on GNU/Linux systems. This file can be used
414 to specify the types of memory mappings that will be included in a
415 corefile. For more information, please refer to the manual page of
416 "core(5)". GDB also has a new command: "set use-coredump-filter
417 on|off". It allows to set whether GDB will read the content of the
418 /proc/PID/coredump_filter file when generating a corefile.
420 * The "info os" command on GNU/Linux can now display information on
422 "info os cpus" Listing of all cpus/cores on the system
424 * GDB has two new commands: "set serial parity odd|even|none" and
425 "show serial parity". These allows to set or show parity for the
428 * The "info source" command now displays the producer string if it was
429 present in the debug info. This typically includes the compiler version
430 and may include things like its command line arguments.
432 * The "info dll", an alias of the "info sharedlibrary" command,
433 is now available on all platforms.
435 * Directory names supplied to the "set sysroot" commands may be
436 prefixed with "target:" to tell GDB to access shared libraries from
437 the target system, be it local or remote. This replaces the prefix
438 "remote:". The default sysroot has been changed from "" to
439 "target:". "remote:" is automatically converted to "target:" for
440 backward compatibility.
442 * The system root specified by "set sysroot" will be prepended to the
443 filename of the main executable (if reported to GDB as absolute by
444 the operating system) when starting processes remotely, and when
445 attaching to already-running local or remote processes.
447 * GDB now supports automatic location and retrieval of executable
448 files from remote targets. Remote debugging can now be initiated
449 using only a "target remote" or "target extended-remote" command
450 (no "set sysroot" or "file" commands are required). See "New remote
453 * The "dump" command now supports verilog hex format.
455 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
457 * On GNU/Linux, GDB and gdbserver are now able to access executable
458 and shared library files without a "set sysroot" command when
459 attaching to processes running in different mount namespaces from
460 the debugger. This makes it possible to attach to processes in
461 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
462 See "New remote packets" below.
464 * The "tui reg" command now provides completion for all of the
465 available register groups, including target specific groups.
467 * The HISTSIZE environment variable is no longer read when determining
468 the size of GDB's command history. GDB now instead reads the dedicated
469 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
470 disables truncation of command history. Non-numeric values of GDBHISTSIZE
475 ** Memory ports can now be unbuffered.
479 ** gdb.Objfile objects have a new attribute "username",
480 which is the name of the objfile as specified by the user,
481 without, for example, resolving symlinks.
482 ** You can now write frame unwinders in Python.
483 ** gdb.Type objects have a new method "optimized_out",
484 returning optimized out gdb.Value instance of this type.
485 ** gdb.Value objects have new methods "reference_value" and
486 "const_value" which return a reference to the value and a
487 "const" version of the value respectively.
491 maint print symbol-cache
492 Print the contents of the symbol cache.
494 maint print symbol-cache-statistics
495 Print statistics of symbol cache usage.
497 maint flush-symbol-cache
498 Flush the contents of the symbol cache.
502 Start branch trace recording using Branch Trace Store (BTS) format.
505 Evaluate expression by using the compiler and print result.
509 Explicit commands for enabling and disabling tui mode.
512 set mpx bound on i386 and amd64
513 Support for bound table investigation on Intel MPX enabled applications.
517 Start branch trace recording using Intel Processor Trace format.
520 Print information about branch tracing internals.
522 maint btrace packet-history
523 Print the raw branch tracing data.
525 maint btrace clear-packet-history
526 Discard the stored raw branch tracing data.
529 Discard all branch tracing data. It will be fetched and processed
530 anew by the next "record" command.
535 Renamed from "set debug dwarf2-die".
537 Renamed from "show debug dwarf2-die".
540 Renamed from "set debug dwarf2-read".
541 show debug dwarf-read
542 Renamed from "show debug dwarf2-read".
544 maint set dwarf always-disassemble
545 Renamed from "maint set dwarf2 always-disassemble".
546 maint show dwarf always-disassemble
547 Renamed from "maint show dwarf2 always-disassemble".
549 maint set dwarf max-cache-age
550 Renamed from "maint set dwarf2 max-cache-age".
551 maint show dwarf max-cache-age
552 Renamed from "maint show dwarf2 max-cache-age".
555 show debug dwarf-line
556 Control display of debugging info regarding DWARF line processing.
560 Set the maximum number of candidates to be considered during
561 completion. The default value is 200. This limit allows GDB
562 to avoid generating large completion lists, the computation of
563 which can cause the debugger to become temporarily unresponsive.
565 set history remove-duplicates
566 show history remove-duplicates
567 Control the removal of duplicate history entries.
569 maint set symbol-cache-size
570 maint show symbol-cache-size
571 Control the size of the symbol cache.
573 set|show record btrace bts buffer-size
574 Set and show the size of the ring buffer used for branch tracing in
576 The obtained size may differ from the requested size. Use "info
577 record" to see the obtained buffer size.
579 set debug linux-namespaces
580 show debug linux-namespaces
581 Control display of debugging info regarding Linux namespaces.
583 set|show record btrace pt buffer-size
584 Set and show the size of the ring buffer used for branch tracing in
585 Intel Processor Trace format.
586 The obtained size may differ from the requested size. Use "info
587 record" to see the obtained buffer size.
589 maint set|show btrace pt skip-pad
590 Set and show whether PAD packets are skipped when computing the
593 * The command 'thread apply all' can now support new option '-ascending'
594 to call its specified command for all threads in ascending order.
596 * Python/Guile scripting
598 ** GDB now supports auto-loading of Python/Guile scripts contained in the
599 special section named `.debug_gdb_scripts'.
603 qXfer:btrace-conf:read
604 Return the branch trace configuration for the current thread.
606 Qbtrace-conf:bts:size
607 Set the requested ring buffer size for branch tracing in BTS format.
610 Enable Intel Procesor Trace-based branch tracing for the current
611 process. The remote stub reports support for this packet to GDB's
615 Set the requested ring buffer size for branch tracing in Intel Processor
619 Indicates a memory breakpoint instruction was executed, irrespective
620 of whether it was GDB that planted the breakpoint or the breakpoint
621 is hardcoded in the program. This is required for correct non-stop
625 Indicates the target stopped for a hardware breakpoint. This is
626 required for correct non-stop mode operation.
629 Return information about files on the remote system.
632 Return the full absolute name of the file that was executed to
633 create a process running on the remote system.
636 Select the filesystem on which vFile: operations with filename
637 arguments will operate. This is required for GDB to be able to
638 access files on remote targets where the remote stub does not
639 share a common filesystem with the inferior(s).
642 Indicates that a fork system call was executed.
645 Indicates that a vfork system call was executed.
647 vforkdone stop reason
648 Indicates that a vfork child of the specified process has executed
649 an exec or exit, allowing the vfork parent to resume execution.
651 fork-events and vfork-events features in qSupported
652 The qSupported packet allows GDB to request support for fork and
653 vfork events using new 'gdbfeatures' fork-events and vfork-events,
654 and the qSupported response can contain the corresponding
655 'stubfeatures'. Set and show commands can be used to display
656 whether these features are enabled.
658 * Extended-remote fork events
660 ** GDB now has support for fork events on extended-remote Linux
661 targets. For targets with Linux kernels 2.5.60 and later, this
662 enables follow-fork-mode and detach-on-fork for both fork and
663 vfork, as well as fork and vfork catchpoints.
665 * The info record command now shows the recording format and the
666 branch tracing configuration for the current thread when using
667 the btrace record target.
668 For the BTS format, it shows the ring buffer size.
670 * GDB now has support for DTrace USDT (Userland Static Defined
671 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
673 * GDB now supports access to vector registers on S/390 GNU/Linux
676 * Removed command line options
678 -xdb HP-UX XDB compatibility mode.
680 * Removed targets and native configurations
682 HP/PA running HP-UX hppa*-*-hpux*
683 Itanium running HP-UX ia64-*-hpux*
685 * New configure options
688 This configure option allows the user to build GDB with support for
689 Intel Processor Trace (default: auto). This requires libipt.
691 --with-libipt-prefix=PATH
692 Specify the path to the version of libipt that GDB should use.
693 $PATH/include should contain the intel-pt.h header and
694 $PATH/lib should contain the libipt.so library.
696 *** Changes in GDB 7.9.1
700 ** Xmethods can now specify a result type.
702 *** Changes in GDB 7.9
704 * GDB now supports hardware watchpoints on x86 GNU Hurd.
708 ** You can now access frame registers from Python scripts.
709 ** New attribute 'producer' for gdb.Symtab objects.
710 ** gdb.Objfile objects have a new attribute "progspace",
711 which is the gdb.Progspace object of the containing program space.
712 ** gdb.Objfile objects have a new attribute "owner".
713 ** gdb.Objfile objects have a new attribute "build_id",
714 which is the build ID generated when the file was built.
715 ** gdb.Objfile objects have a new method "add_separate_debug_file".
716 ** A new event "gdb.clear_objfiles" has been added, triggered when
717 selecting a new file to debug.
718 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
719 ** New function gdb.lookup_objfile.
721 New events which are triggered when GDB modifies the state of the
724 ** gdb.events.inferior_call_pre: Function call is about to be made.
725 ** gdb.events.inferior_call_post: Function call has just been made.
726 ** gdb.events.memory_changed: A memory location has been altered.
727 ** gdb.events.register_changed: A register has been altered.
729 * New Python-based convenience functions:
731 ** $_caller_is(name [, number_of_frames])
732 ** $_caller_matches(regexp [, number_of_frames])
733 ** $_any_caller_is(name [, number_of_frames])
734 ** $_any_caller_matches(regexp [, number_of_frames])
736 * GDB now supports the compilation and injection of source code into
737 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
738 to compile the source code to object code, and if successful, inject
739 and execute that code within the current context of the inferior.
740 Currently the C language is supported. The commands used to
741 interface with this new feature are:
743 compile code [-raw|-r] [--] [source code]
744 compile file [-raw|-r] filename
748 demangle [-l language] [--] name
749 Demangle "name" in the specified language, or the current language
750 if elided. This command is renamed from the "maint demangle" command.
751 The latter is kept as a no-op to avoid "maint demangle" being interpreted
752 as "maint demangler-warning".
754 queue-signal signal-name-or-number
755 Queue a signal to be delivered to the thread when it is resumed.
757 add-auto-load-scripts-directory directory
758 Add entries to the list of directories from which to load auto-loaded
761 maint print user-registers
762 List all currently available "user" registers.
764 compile code [-r|-raw] [--] [source code]
765 Compile, inject, and execute in the inferior the executable object
766 code produced by compiling the provided source code.
768 compile file [-r|-raw] filename
769 Compile and inject into the inferior the executable object code
770 produced by compiling the source code stored in the filename
773 * On resume, GDB now always passes the signal the program had stopped
774 for to the thread the signal was sent to, even if the user changed
775 threads before resuming. Previously GDB would often (but not
776 always) deliver the signal to the thread that happens to be current
779 * Conversely, the "signal" command now consistently delivers the
780 requested signal to the current thread. GDB now asks for
781 confirmation if the program had stopped for a signal and the user
782 switched threads meanwhile.
784 * "breakpoint always-inserted" modes "off" and "auto" merged.
786 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
787 won't remove breakpoints from the target until all threads stop,
788 even in non-stop mode. The "auto" mode has been removed, and "off"
789 is now the default mode.
793 set debug symbol-lookup
794 show debug symbol-lookup
795 Control display of debugging info regarding symbol lookup.
799 ** The -list-thread-groups command outputs an exit-code field for
800 inferiors that have exited.
804 MIPS SDE mips*-sde*-elf*
808 Support for these obsolete configurations has been removed.
810 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
811 SGI Irix-5.x mips-*-irix5*
812 SGI Irix-6.x mips-*-irix6*
813 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
814 VAX running Ultrix vax-*-ultrix*
816 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
817 and "assf"), have been removed. Use the "sharedlibrary" command, or
818 its alias "share", instead.
820 *** Changes in GDB 7.8
822 * New command line options
825 This is an alias for the --data-directory option.
827 * GDB supports printing and modifying of variable length automatic arrays
828 as specified in ISO C99.
830 * The ARM simulator now supports instruction level tracing
831 with or without disassembly.
835 GDB now has support for scripting using Guile. Whether this is
836 available is determined at configure time.
837 Guile version 2.0 or greater is required.
838 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
840 * New commands (for set/show, see "New options" below)
844 Invoke CODE by passing it to the Guile interpreter.
848 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
850 info auto-load guile-scripts [regexp]
851 Print the list of automatically loaded Guile scripts.
853 * The source command is now capable of sourcing Guile scripts.
854 This feature is dependent on the debugger being built with Guile support.
858 set print symbol-loading (off|brief|full)
859 show print symbol-loading
860 Control whether to print informational messages when loading symbol
861 information for a file. The default is "full", but when debugging
862 programs with large numbers of shared libraries the amount of output
865 set guile print-stack (none|message|full)
866 show guile print-stack
867 Show a stack trace when an error is encountered in a Guile script.
869 set auto-load guile-scripts (on|off)
870 show auto-load guile-scripts
871 Control auto-loading of Guile script files.
873 maint ada set ignore-descriptive-types (on|off)
874 maint ada show ignore-descriptive-types
875 Control whether the debugger should ignore descriptive types in Ada
876 programs. The default is not to ignore the descriptive types. See
877 the user manual for more details on descriptive types and the intended
878 usage of this option.
880 set auto-connect-native-target
882 Control whether GDB is allowed to automatically connect to the
883 native target for the run, attach, etc. commands when not connected
884 to any target yet. See also "target native" below.
886 set record btrace replay-memory-access (read-only|read-write)
887 show record btrace replay-memory-access
888 Control what memory accesses are allowed during replay.
890 maint set target-async (on|off)
891 maint show target-async
892 This controls whether GDB targets operate in synchronous or
893 asynchronous mode. Normally the default is asynchronous, if it is
894 available; but this can be changed to more easily debug problems
895 occurring only in synchronous mode.
897 set mi-async (on|off)
899 Control whether MI asynchronous mode is preferred. This supersedes
900 "set target-async" of previous GDB versions.
902 * "set target-async" is deprecated as a CLI option and is now an alias
903 for "set mi-async" (only puts MI into async mode).
905 * Background execution commands (e.g., "c&", "s&", etc.) are now
906 possible ``out of the box'' if the target supports them. Previously
907 the user would need to explicitly enable the possibility with the
908 "set target-async on" command.
910 * New features in the GDB remote stub, GDBserver
912 ** New option --debug-format=option1[,option2,...] allows one to add
913 additional text to each output. At present only timestamps
914 are supported: --debug-format=timestamps.
915 Timestamps can also be turned on with the
916 "monitor set debug-format timestamps" command from GDB.
918 * The 'record instruction-history' command now starts counting instructions
919 at one. This also affects the instruction ranges reported by the
920 'record function-call-history' command when given the /i modifier.
922 * The command 'record function-call-history' supports a new modifier '/c' to
923 indent the function names based on their call stack depth.
924 The fields for the '/i' and '/l' modifier have been reordered.
925 The source line range is now prefixed with 'at'.
926 The instruction range is now prefixed with 'inst'.
927 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
928 "record instruction-history" and "list" commands.
930 * The ranges given as arguments to the 'record function-call-history' and
931 'record instruction-history' commands are now inclusive.
933 * The btrace record target now supports the 'record goto' command.
934 For locations inside the execution trace, the back trace is computed
935 based on the information stored in the execution trace.
937 * The btrace record target supports limited reverse execution and replay.
938 The target does not record data and therefore does not allow reading
941 * The "catch syscall" command now works on s390*-linux* targets.
943 * The "compare-sections" command is no longer specific to target
944 remote. It now works with all targets.
946 * All native targets are now consistently called "native".
947 Consequently, the "target child", "target GNU", "target djgpp",
948 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
949 commands have been replaced with "target native". The QNX/NTO port
950 leaves the "procfs" target in place and adds a "native" target for
951 consistency with other ports. The impact on users should be minimal
952 as these commands previously either throwed an error, or were
953 no-ops. The target's name is visible in the output of the following
954 commands: "help target", "info target", "info files", "maint print
957 * The "target native" command now connects to the native target. This
958 can be used to launch native programs even when "set
959 auto-connect-native-target" is set to off.
961 * GDB now supports access to Intel MPX registers on GNU/Linux.
963 * Support for Intel AVX-512 registers on GNU/Linux.
964 Support displaying and modifying Intel AVX-512 registers
965 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
969 qXfer:btrace:read's annex
970 The qXfer:btrace:read packet supports a new annex 'delta' to read
971 branch trace incrementally.
975 ** Valid Python operations on gdb.Value objects representing
976 structs/classes invoke the corresponding overloaded operators if
978 ** New `Xmethods' feature in the Python API. Xmethods are
979 additional methods or replacements for existing methods of a C++
980 class. This feature is useful for those cases where a method
981 defined in C++ source code could be inlined or optimized out by
982 the compiler, making it unavailable to GDB.
985 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
987 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
988 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
989 its alias "share", instead.
991 * The commands "set remotebaud" and "show remotebaud" are no longer
992 supported. Use "set serial baud" and "show serial baud" (respectively)
997 ** A new option "-gdb-set mi-async" replaces "-gdb-set
998 target-async". The latter is left as a deprecated alias of the
999 former for backward compatibility. If the target supports it,
1000 CLI background execution commands are now always possible by
1001 default, independently of whether the frontend stated a
1002 preference for asynchronous execution with "-gdb-set mi-async".
1003 Previously "-gdb-set target-async off" affected both MI execution
1004 commands and CLI execution commands.
1006 *** Changes in GDB 7.7
1008 * Improved support for process record-replay and reverse debugging on
1009 arm*-linux* targets. Support for thumb32 and syscall instruction
1010 recording has been added.
1012 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1014 * GDB now supports Fission DWP file format version 2.
1015 http://gcc.gnu.org/wiki/DebugFission
1017 * New convenience function "$_isvoid", to check whether an expression
1018 is void. A void expression is an expression where the type of the
1019 result is "void". For example, some convenience variables may be
1020 "void" when evaluated (e.g., "$_exitcode" before the execution of
1021 the program being debugged; or an undefined convenience variable).
1022 Another example, when calling a function whose return type is
1025 * The "maintenance print objfiles" command now takes an optional regexp.
1027 * The "catch syscall" command now works on arm*-linux* targets.
1029 * GDB now consistently shows "<not saved>" when printing values of
1030 registers the debug info indicates have not been saved in the frame
1031 and there's nowhere to retrieve them from
1032 (callee-saved/call-clobbered registers):
1037 (gdb) info registers rax
1040 Before, the former would print "<optimized out>", and the latter
1041 "*value not available*".
1043 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1048 ** Frame filters and frame decorators have been added.
1049 ** Temporary breakpoints are now supported.
1050 ** Line tables representation has been added.
1051 ** New attribute 'parent_type' for gdb.Field objects.
1052 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1053 ** New attribute 'name' for gdb.Type objects.
1057 Nios II ELF nios2*-*-elf
1058 Nios II GNU/Linux nios2*-*-linux
1059 Texas Instruments MSP430 msp430*-*-elf
1061 * Removed native configurations
1063 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1064 been removed. ELF variants of these configurations are kept supported.
1066 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1067 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1068 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1069 i[34567]86-*-openbsd3.[0-3]
1070 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1071 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1072 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1076 Like "catch throw", but catches a re-thrown exception.
1077 maint check-psymtabs
1078 Renamed from old "maint check-symtabs".
1080 Perform consistency checks on symtabs.
1081 maint expand-symtabs
1082 Expand symtabs matching an optional regexp.
1085 Display the details of GDB configure-time options.
1087 maint set|show per-command
1088 maint set|show per-command space
1089 maint set|show per-command time
1090 maint set|show per-command symtab
1091 Enable display of per-command gdb resource usage.
1093 remove-symbol-file FILENAME
1094 remove-symbol-file -a ADDRESS
1095 Remove a symbol file added via add-symbol-file. The file to remove
1096 can be identified by its filename or by an address that lies within
1097 the boundaries of this symbol file in memory.
1100 info exceptions REGEXP
1101 Display the list of Ada exceptions defined in the program being
1102 debugged. If provided, only the exceptions whose names match REGEXP
1107 set debug symfile off|on
1109 Control display of debugging info regarding reading symbol files and
1110 symbol tables within those files
1112 set print raw frame-arguments
1113 show print raw frame-arguments
1114 Set/show whether to print frame arguments in raw mode,
1115 disregarding any defined pretty-printers.
1117 set remote trace-status-packet
1118 show remote trace-status-packet
1119 Set/show the use of remote protocol qTStatus packet.
1123 Control display of debugging messages related to Nios II targets.
1127 Control whether target-assisted range stepping is enabled.
1129 set startup-with-shell
1130 show startup-with-shell
1131 Specifies whether Unix child processes are started via a shell or
1136 Use the target memory cache for accesses to the code segment. This
1137 improves performance of remote debugging (particularly disassembly).
1139 * You can now use a literal value 'unlimited' for options that
1140 interpret 0 or -1 as meaning "unlimited". E.g., "set
1141 trace-buffer-size unlimited" is now an alias for "set
1142 trace-buffer-size -1" and "set height unlimited" is now an alias for
1145 * The "set debug symtab-create" debugging option of GDB has been changed to
1146 accept a verbosity level. 0 means "off", 1 provides basic debugging
1147 output, and values of 2 or greater provides more verbose output.
1149 * New command-line options
1151 Display the details of GDB configure-time options.
1153 * The command 'tsave' can now support new option '-ctf' to save trace
1154 buffer in Common Trace Format.
1156 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1159 * GDB now implements the the C++ 'typeid' operator.
1161 * The new convenience variable $_exception holds the exception being
1162 thrown or caught at an exception-related catchpoint.
1164 * The exception-related catchpoints, like "catch throw", now accept a
1165 regular expression which can be used to filter exceptions by type.
1167 * The new convenience variable $_exitsignal is automatically set to
1168 the terminating signal number when the program being debugged dies
1169 due to an uncaught signal.
1173 ** All MI commands now accept an optional "--language" option.
1174 Support for this feature can be verified by using the "-list-features"
1175 command, which should contain "language-option".
1177 ** The new command -info-gdb-mi-command allows the user to determine
1178 whether a GDB/MI command is supported or not.
1180 ** The "^error" result record returned when trying to execute an undefined
1181 GDB/MI command now provides a variable named "code" whose content is the
1182 "undefined-command" error code. Support for this feature can be verified
1183 by using the "-list-features" command, which should contain
1184 "undefined-command-error-code".
1186 ** The -trace-save MI command can optionally save trace buffer in Common
1189 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1191 ** The command -data-list-register-values now accepts an optional
1192 "--skip-unavailable" option. When used, only the available registers
1195 ** The new command -trace-frame-collected dumps collected variables,
1196 computed expressions, tvars, memory and registers in a traceframe.
1198 ** The commands -stack-list-locals, -stack-list-arguments and
1199 -stack-list-variables now accept an option "--skip-unavailable".
1200 When used, only the available locals or arguments are displayed.
1202 ** The -exec-run command now accepts an optional "--start" option.
1203 When used, the command follows the same semantics as the "start"
1204 command, stopping the program's execution at the start of its
1205 main subprogram. Support for this feature can be verified using
1206 the "-list-features" command, which should contain
1207 "exec-run-start-option".
1209 ** The new commands -catch-assert and -catch-exceptions insert
1210 catchpoints stopping the program when Ada exceptions are raised.
1212 ** The new command -info-ada-exceptions provides the equivalent of
1213 the new "info exceptions" command.
1215 * New system-wide configuration scripts
1216 A GDB installation now provides scripts suitable for use as system-wide
1217 configuration scripts for the following systems:
1221 * GDB now supports target-assigned range stepping with remote targets.
1222 This improves the performance of stepping source lines by reducing
1223 the number of control packets from/to GDB. See "New remote packets"
1226 * GDB now understands the element 'tvar' in the XML traceframe info.
1227 It has the id of the collected trace state variables.
1229 * On S/390 targets that provide the transactional-execution feature,
1230 the program interruption transaction diagnostic block (TDB) is now
1231 represented as a number of additional "registers" in GDB.
1233 * New remote packets
1237 The vCont packet supports a new 'r' action, that tells the remote
1238 stub to step through an address range itself, without GDB
1239 involvemement at each single-step.
1241 qXfer:libraries-svr4:read's annex
1242 The previously unused annex of the qXfer:libraries-svr4:read packet
1243 is now used to support passing an argument list. The remote stub
1244 reports support for this argument list to GDB's qSupported query.
1245 The defined arguments are "start" and "prev", used to reduce work
1246 necessary for library list updating, resulting in significant
1249 * New features in the GDB remote stub, GDBserver
1251 ** GDBserver now supports target-assisted range stepping. Currently
1252 enabled on x86/x86_64 GNU/Linux targets.
1254 ** GDBserver now adds element 'tvar' in the XML in the reply to
1255 'qXfer:traceframe-info:read'. It has the id of the collected
1256 trace state variables.
1258 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1261 * New 'z' formatter for printing and examining memory, this displays the
1262 value as hexadecimal zero padded on the left to the size of the type.
1264 * GDB can now use Windows x64 unwinding data.
1266 * The "set remotebaud" command has been replaced by "set serial baud".
1267 Similarly, "show remotebaud" has been replaced by "show serial baud".
1268 The "set remotebaud" and "show remotebaud" commands are still available
1269 to provide backward compatibility with older versions of GDB.
1271 *** Changes in GDB 7.6
1273 * Target record has been renamed to record-full.
1274 Record/replay is now enabled with the "record full" command.
1275 This also affects settings that are associated with full record/replay
1276 that have been moved from "set/show record" to "set/show record full":
1278 set|show record full insn-number-max
1279 set|show record full stop-at-limit
1280 set|show record full memory-query
1282 * A new record target "record-btrace" has been added. The new target
1283 uses hardware support to record the control-flow of a process. It
1284 does not support replaying the execution, but it implements the
1285 below new commands for investigating the recorded execution log.
1286 This new recording method can be enabled using:
1290 The "record-btrace" target is only available on Intel Atom processors
1291 and requires a Linux kernel 2.6.32 or later.
1293 * Two new commands have been added for record/replay to give information
1294 about the recorded execution without having to replay the execution.
1295 The commands are only supported by "record btrace".
1297 record instruction-history prints the execution history at
1298 instruction granularity
1300 record function-call-history prints the execution history at
1301 function granularity
1303 * New native configurations
1305 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1306 FreeBSD/powerpc powerpc*-*-freebsd
1307 x86_64/Cygwin x86_64-*-cygwin*
1308 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1312 ARM AArch64 aarch64*-*-elf
1313 ARM AArch64 GNU/Linux aarch64*-*-linux
1314 Lynx 178 PowerPC powerpc-*-lynx*178
1315 x86_64/Cygwin x86_64-*-cygwin*
1316 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1318 * If the configured location of system.gdbinit file (as given by the
1319 --with-system-gdbinit option at configure time) is in the
1320 data-directory (as specified by --with-gdb-datadir at configure
1321 time) or in one of its subdirectories, then GDB will look for the
1322 system-wide init file in the directory specified by the
1323 --data-directory command-line option.
1325 * New command line options:
1327 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1328 other initialization files, unlike -nx which disables all of them.
1330 * Removed command line options
1332 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1335 * The 'ptype' and 'whatis' commands now accept an argument to control
1338 * 'info proc' now works on some core files.
1342 ** Vectors can be created with gdb.Type.vector.
1344 ** Python's atexit.register now works in GDB.
1346 ** Types can be pretty-printed via a Python API.
1348 ** Python 3 is now supported (in addition to Python 2.4 or later)
1350 ** New class gdb.Architecture exposes GDB's internal representation
1351 of architecture in the Python API.
1353 ** New method Frame.architecture returns the gdb.Architecture object
1354 corresponding to the frame's architecture.
1356 * New Python-based convenience functions:
1358 ** $_memeq(buf1, buf2, length)
1359 ** $_streq(str1, str2)
1361 ** $_regex(str, regex)
1363 * The 'cd' command now defaults to using '~' (the home directory) if not
1366 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1367 default for GCC since November 2000.
1369 * The command 'forward-search' can now be abbreviated as 'fo'.
1371 * The command 'info tracepoints' can now display 'installed on target'
1372 or 'not installed on target' for each non-pending location of tracepoint.
1374 * New configure options
1376 --enable-libmcheck/--disable-libmcheck
1377 By default, development versions are built with -lmcheck on hosts
1378 that support it, in order to help track memory corruption issues.
1379 Release versions, on the other hand, are built without -lmcheck
1380 by default. The --enable-libmcheck/--disable-libmcheck configure
1381 options allow the user to override that default.
1382 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1383 This configure option allows the user to build GDB with
1384 libbabeltrace using which GDB can read Common Trace Format data.
1386 * New commands (for set/show, see "New options" below)
1389 Catch signals. This is similar to "handle", but allows commands and
1390 conditions to be attached.
1393 List the BFDs known to GDB.
1395 python-interactive [command]
1397 Start a Python interactive prompt, or evaluate the optional command
1398 and print the result of expressions.
1401 "py" is a new alias for "python".
1403 enable type-printer [name]...
1404 disable type-printer [name]...
1405 Enable or disable type printers.
1409 ** For the Renesas Super-H architecture, the "regs" command has been removed
1410 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1415 set print type methods (on|off)
1416 show print type methods
1417 Control whether method declarations are displayed by "ptype".
1418 The default is to show them.
1420 set print type typedefs (on|off)
1421 show print type typedefs
1422 Control whether typedef definitions are displayed by "ptype".
1423 The default is to show them.
1425 set filename-display basename|relative|absolute
1426 show filename-display
1427 Control the way in which filenames is displayed.
1428 The default is "relative", which preserves previous behavior.
1430 set trace-buffer-size
1431 show trace-buffer-size
1432 Request target to change the size of trace buffer.
1434 set remote trace-buffer-size-packet auto|on|off
1435 show remote trace-buffer-size-packet
1436 Control the use of the remote protocol `QTBuffer:size' packet.
1440 Control display of debugging messages related to ARM AArch64.
1443 set debug coff-pe-read
1444 show debug coff-pe-read
1445 Control display of debugging messages related to reading of COFF/PE
1450 Control display of debugging messages related to Mach-O symbols
1453 set debug notification
1454 show debug notification
1455 Control display of debugging info for async remote notification.
1459 ** Command parameter changes are now notified using new async record
1460 "=cmd-param-changed".
1461 ** Trace frame changes caused by command "tfind" are now notified using
1462 new async record "=traceframe-changed".
1463 ** The creation, deletion and modification of trace state variables
1464 are now notified using new async records "=tsv-created",
1465 "=tsv-deleted" and "=tsv-modified".
1466 ** The start and stop of process record are now notified using new
1467 async record "=record-started" and "=record-stopped".
1468 ** Memory changes are now notified using new async record
1470 ** The data-disassemble command response will include a "fullname" field
1471 containing the absolute file name when source has been requested.
1472 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1473 command, to allow pattern filling of memory areas.
1474 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1475 library load/unload events.
1476 ** The response to breakpoint commands and breakpoint async records
1477 includes an "installed" field containing a boolean state about each
1478 non-pending tracepoint location is whether installed on target or not.
1479 ** Output of the "-trace-status" command includes a "trace-file" field
1480 containing the name of the trace file being examined. This field is
1481 optional, and only present when examining a trace file.
1482 ** The "fullname" field is now always present along with the "file" field,
1483 even if the file cannot be found by GDB.
1485 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1486 You must have the LZMA library available when configuring GDB for this
1487 feature to be enabled. For more information, see:
1488 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1490 * New remote packets
1493 Set the size of trace buffer. The remote stub reports support for this
1494 packet to gdb's qSupported query.
1497 Enable Branch Trace Store (BTS)-based branch tracing for the current
1498 thread. The remote stub reports support for this packet to gdb's
1502 Disable branch tracing for the current thread. The remote stub reports
1503 support for this packet to gdb's qSupported query.
1506 Read the traced branches for the current thread. The remote stub
1507 reports support for this packet to gdb's qSupported query.
1509 *** Changes in GDB 7.5
1511 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1512 for more x32 ABI info.
1514 * GDB now supports access to MIPS DSP registers on Linux targets.
1516 * GDB now supports debugging microMIPS binaries.
1518 * The "info os" command on GNU/Linux can now display information on
1519 several new classes of objects managed by the operating system:
1520 "info os procgroups" lists process groups
1521 "info os files" lists file descriptors
1522 "info os sockets" lists internet-domain sockets
1523 "info os shm" lists shared-memory regions
1524 "info os semaphores" lists semaphores
1525 "info os msg" lists message queues
1526 "info os modules" lists loaded kernel modules
1528 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1529 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1530 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1531 options and inspect the probe arguments using the new $_probe_arg family
1532 of convenience variables. You can obtain more information about SystemTap
1533 in <http://sourceware.org/systemtap/>.
1535 * GDB now supports reversible debugging on ARM, it allows you to
1536 debug basic ARM and THUMB instructions, and provides
1537 record/replay support.
1539 * The option "symbol-reloading" has been deleted as it is no longer used.
1543 ** GDB commands implemented in Python can now be put in command class
1546 ** The "maint set python print-stack on|off" is now deleted.
1548 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1549 apply "flag enum"-style pretty-printing to any enum.
1551 ** gdb.lookup_symbol can now work when there is no current frame.
1553 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1554 the source at which the symbol was defined.
1556 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1557 method 'value'. The former indicates whether the symbol needs a
1558 frame in order to compute its value, and the latter computes the
1561 ** A new method 'referenced_value' on gdb.Value objects which can
1562 dereference pointer as well as C++ reference values.
1564 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1565 which return the global and static blocks (as gdb.Block objects),
1566 of the underlying symbol table, respectively.
1568 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1569 object associated with a PC value.
1571 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1572 of the address range occupied by code for the current source line.
1574 * Go language support.
1575 GDB now supports debugging programs written in the Go programming
1578 * GDBserver now supports stdio connections.
1579 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1581 * The binary "gdbtui" can no longer be built or installed.
1582 Use "gdb -tui" instead.
1584 * GDB will now print "flag" enums specially. A flag enum is one where
1585 all the enumerator values have no bits in common when pairwise
1586 "and"ed. When printing a value whose type is a flag enum, GDB will
1587 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1588 (gdb) print (enum E) 3
1591 * The filename part of a linespec will now match trailing components
1592 of a source file name. For example, "break gcc/expr.c:1000" will
1593 now set a breakpoint in build/gcc/expr.c, but not
1594 build/libcpp/expr.c.
1596 * The "info proc" and "generate-core-file" commands will now also
1597 work on remote targets connected to GDBserver on Linux.
1599 * The command "info catch" has been removed. It has been disabled
1600 since December 2007.
1602 * The "catch exception" and "catch assert" commands now accept
1603 a condition at the end of the command, much like the "break"
1604 command does. For instance:
1606 (gdb) catch exception Constraint_Error if Barrier = True
1608 Previously, it was possible to add a condition to such catchpoints,
1609 but it had to be done as a second step, after the catchpoint had been
1610 created, using the "condition" command.
1612 * The "info static-tracepoint-marker" command will now also work on
1613 native Linux targets with in-process agent.
1615 * GDB can now set breakpoints on inlined functions.
1617 * The .gdb_index section has been updated to include symbols for
1618 inlined functions. GDB will ignore older .gdb_index sections by
1619 default, which could cause symbol files to be loaded more slowly
1620 until their .gdb_index sections can be recreated. The new command
1621 "set use-deprecated-index-sections on" will cause GDB to use any older
1622 .gdb_index sections it finds. This will restore performance, but the
1623 ability to set breakpoints on inlined functions will be lost in symbol
1624 files with older .gdb_index sections.
1626 The .gdb_index section has also been updated to record more information
1627 about each symbol. This speeds up the "info variables", "info functions"
1628 and "info types" commands when used with programs having the .gdb_index
1629 section, as well as speeding up debugging with shared libraries using
1630 the .gdb_index section.
1632 * Ada support for GDB/MI Variable Objects has been added.
1634 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1639 ** New command -info-os is the MI equivalent of "info os".
1641 ** Output logs ("set logging" and related) now include MI output.
1645 ** "set use-deprecated-index-sections on|off"
1646 "show use-deprecated-index-sections on|off"
1647 Controls the use of deprecated .gdb_index sections.
1649 ** "catch load" and "catch unload" can be used to stop when a shared
1650 library is loaded or unloaded, respectively.
1652 ** "enable count" can be used to auto-disable a breakpoint after
1655 ** "info vtbl" can be used to show the virtual method tables for
1656 C++ and Java objects.
1658 ** "explore" and its sub commands "explore value" and "explore type"
1659 can be used to recursively explore values and types of
1660 expressions. These commands are available only if GDB is
1661 configured with '--with-python'.
1663 ** "info auto-load" shows status of all kinds of auto-loaded files,
1664 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1665 sequences of commands files, "info auto-load python-scripts"
1666 shows status of auto-loading Python script files,
1667 "info auto-load local-gdbinit" shows status of loading init file
1668 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1669 status of inferior specific thread debugging shared library loading.
1671 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1672 and "show auto-load-scripts" commands have been deprecated, use their
1673 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1674 and "show auto-load python-scripts" counterparts instead.
1676 ** "dprintf location,format,args..." creates a dynamic printf, which
1677 is basically a breakpoint that does a printf and immediately
1678 resumes your program's execution, so it is like a printf that you
1679 can insert dynamically at runtime instead of at compiletime.
1681 ** "set print symbol"
1683 Controls whether GDB attempts to display the symbol, if any,
1684 corresponding to addresses it prints. This defaults to "on", but
1685 you can set it to "off" to restore GDB's previous behavior.
1687 * Deprecated commands
1689 ** For the Renesas Super-H architecture, the "regs" command has been
1690 deprecated, and "info all-registers" should be used instead.
1694 Renesas RL78 rl78-*-elf
1695 HP OpenVMS ia64 ia64-hp-openvms*
1697 * GDBserver supports evaluation of breakpoint conditions. When
1698 support is advertised by GDBserver, GDB may be told to send the
1699 breakpoint conditions in bytecode form to GDBserver. GDBserver
1700 will only report the breakpoint trigger to GDB when its condition
1705 set mips compression
1706 show mips compression
1707 Select the compressed ISA encoding used in functions that have no symbol
1708 information available. The encoding can be set to either of:
1711 and is updated automatically from ELF file flags if available.
1713 set breakpoint condition-evaluation
1714 show breakpoint condition-evaluation
1715 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1716 GDBserver ("target"). Default option "auto" chooses the most efficient
1718 This option can improve debugger efficiency depending on the speed of the
1722 Disable auto-loading globally.
1725 Show auto-loading setting of all kinds of auto-loaded files.
1727 set auto-load gdb-scripts on|off
1728 show auto-load gdb-scripts
1729 Control auto-loading of GDB canned sequences of commands files.
1731 set auto-load python-scripts on|off
1732 show auto-load python-scripts
1733 Control auto-loading of Python script files.
1735 set auto-load local-gdbinit on|off
1736 show auto-load local-gdbinit
1737 Control loading of init file (.gdbinit) from current directory.
1739 set auto-load libthread-db on|off
1740 show auto-load libthread-db
1741 Control auto-loading of inferior specific thread debugging shared library.
1743 set auto-load scripts-directory <dir1>[:<dir2>...]
1744 show auto-load scripts-directory
1745 Set a list of directories from which to load auto-loaded scripts.
1746 Automatically loaded Python scripts and GDB scripts are located in one
1747 of the directories listed by this option.
1748 The delimiter (':' above) may differ according to the host platform.
1750 set auto-load safe-path <dir1>[:<dir2>...]
1751 show auto-load safe-path
1752 Set a list of directories from which it is safe to auto-load files.
1753 The delimiter (':' above) may differ according to the host platform.
1755 set debug auto-load on|off
1756 show debug auto-load
1757 Control display of debugging info for auto-loading the files above.
1759 set dprintf-style gdb|call|agent
1761 Control the way in which a dynamic printf is performed; "gdb"
1762 requests a GDB printf command, while "call" causes dprintf to call a
1763 function in the inferior. "agent" requests that the target agent
1764 (such as GDBserver) do the printing.
1766 set dprintf-function <expr>
1767 show dprintf-function
1768 set dprintf-channel <expr>
1769 show dprintf-channel
1770 Set the function and optional first argument to the call when using
1771 the "call" style of dynamic printf.
1773 set disconnected-dprintf on|off
1774 show disconnected-dprintf
1775 Control whether agent-style dynamic printfs continue to be in effect
1776 after GDB disconnects.
1778 * New configure options
1780 --with-auto-load-dir
1781 Configure default value for the 'set auto-load scripts-directory'
1782 setting above. It defaults to '$debugdir:$datadir/auto-load',
1783 $debugdir representing global debugging info directories (available
1784 via 'show debug-file-directory') and $datadir representing GDB's data
1785 directory (available via 'show data-directory').
1787 --with-auto-load-safe-path
1788 Configure default value for the 'set auto-load safe-path' setting
1789 above. It defaults to the --with-auto-load-dir setting.
1791 --without-auto-load-safe-path
1792 Set 'set auto-load safe-path' to '/', effectively disabling this
1795 * New remote packets
1797 z0/z1 conditional breakpoints extension
1799 The z0/z1 breakpoint insertion packets have been extended to carry
1800 a list of conditional expressions over to the remote stub depending on the
1801 condition evaluation mode. The use of this extension can be controlled
1802 via the "set remote conditional-breakpoints-packet" command.
1806 Specify the signals which the remote stub may pass to the debugged
1807 program without GDB involvement.
1809 * New command line options
1811 --init-command=FILE, -ix Like --command, -x but execute it
1812 before loading inferior.
1813 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1814 execute it before loading inferior.
1816 *** Changes in GDB 7.4
1818 * GDB now handles ambiguous linespecs more consistently; the existing
1819 FILE:LINE support has been expanded to other types of linespecs. A
1820 breakpoint will now be set on all matching locations in all
1821 inferiors, and locations will be added or removed according to
1824 * GDB now allows you to skip uninteresting functions and files when
1825 stepping with the "skip function" and "skip file" commands.
1827 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1828 and "show remote hardware-watchpoint-length-limit". These allows to
1829 set or show the maximum length limit (in bytes) of a remote
1830 target hardware watchpoint.
1832 This allows e.g. to use "unlimited" hardware watchpoints with the
1833 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1834 watchpoints are slower than real hardware watchpoints but are
1835 significantly faster than gdb software watchpoints.
1839 ** The register_pretty_printer function in module gdb.printing now takes
1840 an optional `replace' argument. If True, the new printer replaces any
1843 ** The "maint set python print-stack on|off" command has been
1844 deprecated and will be deleted in GDB 7.5.
1845 A new command: "set python print-stack none|full|message" has
1846 replaced it. Additionally, the default for "print-stack" is
1847 now "message", which just prints the error message without
1850 ** A prompt substitution hook (prompt_hook) is now available to the
1853 ** A new Python module, gdb.prompt has been added to the GDB Python
1854 modules library. This module provides functionality for
1855 escape sequences in prompts (used by set/show
1856 extended-prompt). These escape sequences are replaced by their
1857 corresponding value.
1859 ** Python commands and convenience-functions located in
1860 'data-directory'/python/gdb/command and
1861 'data-directory'/python/gdb/function are now automatically loaded
1864 ** Blocks now provide four new attributes. global_block and
1865 static_block will return the global and static blocks
1866 respectively. is_static and is_global are boolean attributes
1867 that indicate if the block is one of those two types.
1869 ** Symbols now provide the "type" attribute, the type of the symbol.
1871 ** The "gdb.breakpoint" function has been deprecated in favor of
1874 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1875 of a function. This class is based on the "finish" command
1876 available in the CLI.
1878 ** Type objects for struct and union types now allow access to
1879 the fields using standard Python dictionary (mapping) methods.
1880 For example, "some_type['myfield']" now works, as does
1881 "some_type.items()".
1883 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1886 ** A new function, "deep_items" has been added to the gdb.types
1887 module in the GDB Python modules library. This function returns
1888 an iterator over the fields of a struct or union type. Unlike
1889 the standard Python "iteritems" method, it will recursively traverse
1890 any anonymous fields.
1894 ** "*stopped" events can report several new "reason"s, such as
1897 ** Breakpoint changes are now notified using new async records, like
1898 "=breakpoint-modified".
1900 ** New command -ada-task-info.
1902 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1903 $sdir specifies the default system locations of shared libraries.
1904 $pdir specifies the directory where the libpthread used by the application
1907 GDB no longer looks in $sdir and $pdir after it has searched the directories
1908 mentioned in libthread-db-search-path. If you want to search those
1909 directories, they must be specified in libthread-db-search-path.
1910 The default value of libthread-db-search-path on GNU/Linux and Solaris
1911 systems is now "$sdir:$pdir".
1913 $pdir is not supported by gdbserver, it is currently ignored.
1914 $sdir is supported by gdbserver.
1916 * New configure option --with-iconv-bin.
1917 When using the internationalization support like the one in the GNU C
1918 library, GDB will invoke the "iconv" program to get a list of supported
1919 character sets. If this program lives in a non-standard location, one can
1920 use this option to specify where to find it.
1922 * When natively debugging programs on PowerPC BookE processors running
1923 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1924 watchpoints, which specify a mask in addition to an address to watch.
1925 The mask specifies that some bits of an address (the bits which are
1926 reset in the mask) should be ignored when matching the address accessed
1927 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1928 section in the user manual for more details.
1930 * The new option --once causes GDBserver to stop listening for connections once
1931 the first connection is made. The listening port used by GDBserver will
1932 become available after that.
1934 * New commands "info macros" and "alias" have been added.
1936 * New function parameters suffix @entry specifies value of function parameter
1937 at the time the function got called. Entry values are available only since
1943 "!" is now an alias of the "shell" command.
1944 Note that no space is needed between "!" and SHELL COMMAND.
1948 watch EXPRESSION mask MASK_VALUE
1949 The watch command now supports the mask argument which allows creation
1950 of masked watchpoints, if the current architecture supports this feature.
1952 info auto-load-scripts [REGEXP]
1953 This command was formerly named "maintenance print section-scripts".
1954 It is now generally useful and is no longer a maintenance-only command.
1956 info macro [-all] [--] MACRO
1957 The info macro command has new options `-all' and `--'. The first for
1958 printing all definitions of a macro. The second for explicitly specifying
1959 the end of arguments and the beginning of the macro name in case the macro
1960 name starts with a hyphen.
1962 collect[/s] EXPRESSIONS
1963 The tracepoint collect command now takes an optional modifier "/s"
1964 that directs it to dereference pointer-to-character types and
1965 collect the bytes of memory up to a zero byte. The behavior is
1966 similar to what you see when you use the regular print command on a
1967 string. An optional integer following the "/s" sets a bound on the
1968 number of bytes that will be collected.
1971 The trace start command now interprets any supplied arguments as a
1972 note to be recorded with the trace run, with an effect similar to
1973 setting the variable trace-notes.
1976 The trace stop command now interprets any arguments as a note to be
1977 mentioned along with the tstatus report that the trace was stopped
1978 with a command. The effect is similar to setting the variable
1981 * Tracepoints can now be enabled and disabled at any time after a trace
1982 experiment has been started using the standard "enable" and "disable"
1983 commands. It is now possible to start a trace experiment with no enabled
1984 tracepoints; GDB will display a warning, but will allow the experiment to
1985 begin, assuming that tracepoints will be enabled as needed while the trace
1988 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1989 locations with 4-byte instructions, when they were previously
1990 limited to locations with instructions of 5 bytes or longer.
1994 set debug dwarf2-read
1995 show debug dwarf2-read
1996 Turns on or off display of debugging messages related to reading
1997 DWARF debug info. The default is off.
1999 set debug symtab-create
2000 show debug symtab-create
2001 Turns on or off display of debugging messages related to symbol table
2002 creation. The default is off.
2005 show extended-prompt
2006 Set the GDB prompt, and allow escape sequences to be inserted to
2007 display miscellaneous information (see 'help set extended-prompt'
2008 for the list of sequences). This prompt (and any information
2009 accessed through the escape sequences) is updated every time the
2010 prompt is displayed.
2012 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2013 show print entry-values
2014 Set printing of frame argument values at function entry. In some cases
2015 GDB can determine the value of function argument which was passed by the
2016 function caller, even if the value was modified inside the called function.
2018 set debug entry-values
2019 show debug entry-values
2020 Control display of debugging info for determining frame argument values at
2021 function entry and virtual tail call frames.
2023 set basenames-may-differ
2024 show basenames-may-differ
2025 Set whether a source file may have multiple base names.
2026 (A "base name" is the name of a file with the directory part removed.
2027 Example: The base name of "/home/user/hello.c" is "hello.c".)
2028 If set, GDB will canonicalize file names (e.g., expand symlinks)
2029 before comparing them. Canonicalization is an expensive operation,
2030 but it allows the same file be known by more than one base name.
2031 If not set (the default), all source files are assumed to have just
2032 one base name, and gdb will do file name comparisons more efficiently.
2038 Set a user name and notes for the current and any future trace runs.
2039 This is useful for long-running and/or disconnected traces, to
2040 inform others (or yourself) as to who is running the trace, supply
2041 contact information, or otherwise explain what is going on.
2043 set trace-stop-notes
2044 show trace-stop-notes
2045 Set a note attached to the trace run, that is displayed when the
2046 trace has been stopped by a tstop command. This is useful for
2047 instance as an explanation, if you are stopping a trace run that was
2048 started by someone else.
2050 * New remote packets
2054 Dynamically enable a tracepoint in a started trace experiment.
2058 Dynamically disable a tracepoint in a started trace experiment.
2062 Set the user and notes of the trace run.
2066 Query the current status of a tracepoint.
2070 Query the minimum length of instruction at which a fast tracepoint may
2073 * Dcache size (number of lines) and line-size are now runtime-configurable
2074 via "set dcache line" and "set dcache line-size" commands.
2078 Texas Instruments TMS320C6x tic6x-*-*
2082 Renesas RL78 rl78-*-elf
2084 *** Changes in GDB 7.3.1
2086 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2088 *** Changes in GDB 7.3
2090 * GDB has a new command: "thread find [REGEXP]".
2091 It finds the thread id whose name, target id, or thread extra info
2092 matches the given regular expression.
2094 * The "catch syscall" command now works on mips*-linux* targets.
2096 * The -data-disassemble MI command now supports modes 2 and 3 for
2097 dumping the instruction opcodes.
2099 * New command line options
2101 -data-directory DIR Specify DIR as the "data-directory".
2102 This is mostly for testing purposes.
2104 * The "maint set python auto-load on|off" command has been renamed to
2105 "set auto-load-scripts on|off".
2107 * GDB has a new command: "set directories".
2108 It is like the "dir" command except that it replaces the
2109 source path list instead of augmenting it.
2111 * GDB now understands thread names.
2113 On GNU/Linux, "info threads" will display the thread name as set by
2114 prctl or pthread_setname_np.
2116 There is also a new command, "thread name", which can be used to
2117 assign a name internally for GDB to display.
2120 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2121 has been integrated into GDB.
2125 ** The function gdb.Write now accepts an optional keyword 'stream'.
2126 This keyword, when provided, will direct the output to either
2127 stdout, stderr, or GDB's logging output.
2129 ** Parameters can now be be sub-classed in Python, and in particular
2130 you may implement the get_set_doc and get_show_doc functions.
2131 This improves how Parameter set/show documentation is processed
2132 and allows for more dynamic content.
2134 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2135 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2136 have an is_valid method.
2138 ** Breakpoints can now be sub-classed in Python, and in particular
2139 you may implement a 'stop' function that is executed each time
2140 the inferior reaches that breakpoint.
2142 ** New function gdb.lookup_global_symbol looks up a global symbol.
2144 ** GDB values in Python are now callable if the value represents a
2145 function. For example, if 'some_value' represents a function that
2146 takes two integer parameters and returns a value, you can call
2147 that function like so:
2149 result = some_value (10,20)
2151 ** Module gdb.types has been added.
2152 It contains a collection of utilities for working with gdb.Types objects:
2153 get_basic_type, has_field, make_enum_dict.
2155 ** Module gdb.printing has been added.
2156 It contains utilities for writing and registering pretty-printers.
2157 New classes: PrettyPrinter, SubPrettyPrinter,
2158 RegexpCollectionPrettyPrinter.
2159 New function: register_pretty_printer.
2161 ** New commands "info pretty-printers", "enable pretty-printer" and
2162 "disable pretty-printer" have been added.
2164 ** gdb.parameter("directories") is now available.
2166 ** New function gdb.newest_frame returns the newest frame in the
2169 ** The gdb.InferiorThread class has a new "name" attribute. This
2170 holds the thread's name.
2172 ** Python Support for Inferior events.
2173 Python scripts can add observers to be notified of events
2174 occurring in the process being debugged.
2175 The following events are currently supported:
2176 - gdb.events.cont Continue event.
2177 - gdb.events.exited Inferior exited event.
2178 - gdb.events.stop Signal received, and Breakpoint hit events.
2182 ** GDB now puts template parameters in scope when debugging in an
2183 instantiation. For example, if you have:
2185 template<int X> int func (void) { return X; }
2187 then if you step into func<5>, "print X" will show "5". This
2188 feature requires proper debuginfo support from the compiler; it
2189 was added to GCC 4.5.
2191 ** The motion commands "next", "finish", "until", and "advance" now
2192 work better when exceptions are thrown. In particular, GDB will
2193 no longer lose control of the inferior; instead, the GDB will
2194 stop the inferior at the point at which the exception is caught.
2195 This functionality requires a change in the exception handling
2196 code that was introduced in GCC 4.5.
2198 * GDB now follows GCC's rules on accessing volatile objects when
2199 reading or writing target state during expression evaluation.
2200 One notable difference to prior behavior is that "print x = 0"
2201 no longer generates a read of x; the value of the assignment is
2202 now always taken directly from the value being assigned.
2204 * GDB now has some support for using labels in the program's source in
2205 linespecs. For instance, you can use "advance label" to continue
2206 execution to a label.
2208 * GDB now has support for reading and writing a new .gdb_index
2209 section. This section holds a fast index of DWARF debugging
2210 information and can be used to greatly speed up GDB startup and
2211 operation. See the documentation for `save gdb-index' for details.
2213 * The "watch" command now accepts an optional "-location" argument.
2214 When used, this causes GDB to watch the memory referred to by the
2215 expression. Such a watchpoint is never deleted due to it going out
2218 * GDB now supports thread debugging of core dumps on GNU/Linux.
2220 GDB now activates thread debugging using the libthread_db library
2221 when debugging GNU/Linux core dumps, similarly to when debugging
2222 live processes. As a result, when debugging a core dump file, GDB
2223 is now able to display pthread_t ids of threads. For example, "info
2224 threads" shows the same output as when debugging the process when it
2225 was live. In earlier releases, you'd see something like this:
2228 * 1 LWP 6780 main () at main.c:10
2230 While now you see this:
2233 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2235 It is also now possible to inspect TLS variables when debugging core
2238 When debugging a core dump generated on a machine other than the one
2239 used to run GDB, you may need to point GDB at the correct
2240 libthread_db library with the "set libthread-db-search-path"
2241 command. See the user manual for more details on this command.
2243 * When natively debugging programs on PowerPC BookE processors running
2244 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2245 which stop execution of the inferior whenever it executes an instruction
2246 at any address within the specified range. See the "PowerPC Embedded"
2247 section in the user manual for more details.
2249 * New features in the GDB remote stub, GDBserver
2251 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2252 and i686 LynxOS (version 5.x).
2254 ** GDBserver is now supported on Blackfin Linux.
2256 * New native configurations
2258 ia64 HP-UX ia64-*-hpux*
2262 Analog Devices, Inc. Blackfin Processor bfin-*
2264 * Ada task switching is now supported on sparc-elf targets when
2265 debugging a program using the Ravenscar Profile. For more information,
2266 see the "Tasking Support when using the Ravenscar Profile" section
2267 in the GDB user manual.
2269 * Guile support was removed.
2271 * New features in the GNU simulator
2273 ** The --map-info flag lists all known core mappings.
2275 ** CFI flashes may be simulated via the "cfi" device.
2277 *** Changes in GDB 7.2
2279 * Shared library support for remote targets by default
2281 When GDB is configured for a generic, non-OS specific target, like
2282 for example, --target=arm-eabi or one of the many *-*-elf targets,
2283 GDB now queries remote stubs for loaded shared libraries using the
2284 `qXfer:libraries:read' packet. Previously, shared library support
2285 was always disabled for such configurations.
2289 ** Argument Dependent Lookup (ADL)
2291 In C++ ADL lookup directs function search to the namespaces of its
2292 arguments even if the namespace has not been imported.
2302 Here the compiler will search for `foo' in the namespace of 'b'
2303 and find A::foo. GDB now supports this. This construct is commonly
2304 used in the Standard Template Library for operators.
2306 ** Improved User Defined Operator Support
2308 In addition to member operators, GDB now supports lookup of operators
2309 defined in a namespace and imported with a `using' directive, operators
2310 defined in the global scope, operators imported implicitly from an
2311 anonymous namespace, and the ADL operators mentioned in the previous
2313 GDB now also supports proper overload resolution for all the previously
2314 mentioned flavors of operators.
2316 ** static const class members
2318 Printing of static const class members that are initialized in the
2319 class definition has been fixed.
2321 * Windows Thread Information Block access.
2323 On Windows targets, GDB now supports displaying the Windows Thread
2324 Information Block (TIB) structure. This structure is visible either
2325 by using the new command `info w32 thread-information-block' or, by
2326 dereferencing the new convenience variable named `$_tlb', a
2327 thread-specific pointer to the TIB. This feature is also supported
2328 when remote debugging using GDBserver.
2330 * Static tracepoints
2332 Static tracepoints are calls in the user program into a tracing
2333 library. One such library is a port of the LTTng kernel tracer to
2334 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2335 When debugging with GDBserver, GDB now supports combining the GDB
2336 tracepoint machinery with such libraries. For example: the user can
2337 use GDB to probe a static tracepoint marker (a call from the user
2338 program into the tracing library) with the new "strace" command (see
2339 "New commands" below). This creates a "static tracepoint" in the
2340 breakpoint list, that can be manipulated with the same feature set
2341 as fast and regular tracepoints. E.g., collect registers, local and
2342 global variables, collect trace state variables, and define
2343 tracepoint conditions. In addition, the user can collect extra
2344 static tracepoint marker specific data, by collecting the new
2345 $_sdata internal variable. When analyzing the trace buffer, you can
2346 inspect $_sdata like any other variable available to GDB. For more
2347 information, see the "Tracepoints" chapter in GDB user manual. New
2348 remote packets have been defined to support static tracepoints, see
2349 the "New remote packets" section below.
2351 * Better reconstruction of tracepoints after disconnected tracing
2353 GDB will attempt to download the original source form of tracepoint
2354 definitions when starting a trace run, and then will upload these
2355 upon reconnection to the target, resulting in a more accurate
2356 reconstruction of the tracepoints that are in use on the target.
2360 You can now exercise direct control over the ways that GDB can
2361 affect your program. For instance, you can disallow the setting of
2362 breakpoints, so that the program can run continuously (assuming
2363 non-stop mode). In addition, the "observer" variable is available
2364 to switch all of the different controls; in observer mode, GDB
2365 cannot affect the target's behavior at all, which is useful for
2366 tasks like diagnosing live systems in the field.
2368 * The new convenience variable $_thread holds the number of the
2371 * New remote packets
2375 Return the address of the Windows Thread Information Block of a given thread.
2379 In response to several of the tracepoint packets, the target may now
2380 also respond with a number of intermediate `qRelocInsn' request
2381 packets before the final result packet, to have GDB handle
2382 relocating an instruction to execute at a different address. This
2383 is particularly useful for stubs that support fast tracepoints. GDB
2384 reports support for this feature in the qSupported packet.
2388 List static tracepoint markers in the target program.
2392 List static tracepoint markers at a given address in the target
2395 qXfer:statictrace:read
2397 Read the static trace data collected (by a `collect $_sdata'
2398 tracepoint action). The remote stub reports support for this packet
2399 to gdb's qSupported query.
2403 Send the current settings of GDB's permission flags.
2407 Send part of the source (textual) form of a tracepoint definition,
2408 which includes location, conditional, and action list.
2410 * The source command now accepts a -s option to force searching for the
2411 script in the source search path even if the script name specifies
2414 * New features in the GDB remote stub, GDBserver
2416 - GDBserver now support tracepoints (including fast tracepoints, and
2417 static tracepoints). The feature is currently supported by the
2418 i386-linux and amd64-linux builds. See the "Tracepoints support
2419 in gdbserver" section in the manual for more information.
2421 GDBserver JIT compiles the tracepoint's conditional agent
2422 expression bytecode into native code whenever possible for low
2423 overhead dynamic tracepoints conditionals. For such tracepoints,
2424 an expression that examines program state is evaluated when the
2425 tracepoint is reached, in order to determine whether to capture
2426 trace data. If the condition is simple and false, processing the
2427 tracepoint finishes very quickly and no data is gathered.
2429 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2430 for static tracepoints support.
2432 - GDBserver now supports x86_64 Windows 64-bit debugging.
2434 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2435 it understands register description.
2437 * The --batch flag now disables pagination and queries.
2439 * X86 general purpose registers
2441 GDB now supports reading/writing byte, word and double-word x86
2442 general purpose registers directly. This means you can use, say,
2443 $ah or $ax to refer, respectively, to the byte register AH and
2444 16-bit word register AX that are actually portions of the 32-bit
2445 register EAX or 64-bit register RAX.
2447 * The `commands' command now accepts a range of breakpoints to modify.
2448 A plain `commands' following a command that creates multiple
2449 breakpoints affects all the breakpoints set by that command. This
2450 applies to breakpoints set by `rbreak', and also applies when a
2451 single `break' command creates multiple breakpoints (e.g.,
2452 breakpoints on overloaded c++ functions).
2454 * The `rbreak' command now accepts a filename specification as part of
2455 its argument, limiting the functions selected by the regex to those
2456 in the specified file.
2458 * Support for remote debugging Windows and SymbianOS shared libraries
2459 from Unix hosts has been improved. Non Windows GDB builds now can
2460 understand target reported file names that follow MS-DOS based file
2461 system semantics, such as file names that include drive letters and
2462 use the backslash character as directory separator. This makes it
2463 possible to transparently use the "set sysroot" and "set
2464 solib-search-path" on Unix hosts to point as host copies of the
2465 target's shared libraries. See the new command "set
2466 target-file-system-kind" described below, and the "Commands to
2467 specify files" section in the user manual for more information.
2471 eval template, expressions...
2472 Convert the values of one or more expressions under the control
2473 of the string template to a command line, and call it.
2475 set target-file-system-kind unix|dos-based|auto
2476 show target-file-system-kind
2477 Set or show the assumed file system kind for target reported file
2480 save breakpoints <filename>
2481 Save all current breakpoint definitions to a file suitable for use
2482 in a later debugging session. To read the saved breakpoint
2483 definitions, use the `source' command.
2485 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2488 info static-tracepoint-markers
2489 Display information about static tracepoint markers in the target.
2491 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2492 Define a static tracepoint by probing a marker at the given
2493 function, line, address, or marker ID.
2497 Enable and disable observer mode.
2499 set may-write-registers on|off
2500 set may-write-memory on|off
2501 set may-insert-breakpoints on|off
2502 set may-insert-tracepoints on|off
2503 set may-insert-fast-tracepoints on|off
2504 set may-interrupt on|off
2505 Set individual permissions for GDB effects on the target. Note that
2506 some of these settings can have undesirable or surprising
2507 consequences, particularly when changed in the middle of a session.
2508 For instance, disabling the writing of memory can prevent
2509 breakpoints from being inserted, cause single-stepping to fail, or
2510 even crash your program, if you disable after breakpoints have been
2511 inserted. However, GDB should not crash.
2513 set record memory-query on|off
2514 show record memory-query
2515 Control whether to stop the inferior if memory changes caused
2516 by an instruction cannot be recorded.
2521 The disassemble command now supports "start,+length" form of two arguments.
2525 ** GDB now provides a new directory location, called the python directory,
2526 where Python scripts written for GDB can be installed. The location
2527 of that directory is <data-directory>/python, where <data-directory>
2528 is the GDB data directory. For more details, see section `Scripting
2529 GDB using Python' in the manual.
2531 ** The GDB Python API now has access to breakpoints, symbols, symbol
2532 tables, program spaces, inferiors, threads and frame's code blocks.
2533 Additionally, GDB Parameters can now be created from the API, and
2534 manipulated via set/show in the CLI.
2536 ** New functions gdb.target_charset, gdb.target_wide_charset,
2537 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2539 ** New exception gdb.GdbError.
2541 ** Pretty-printers are now also looked up in the current program space.
2543 ** Pretty-printers can now be individually enabled and disabled.
2545 ** GDB now looks for names of Python scripts to auto-load in a
2546 special section named `.debug_gdb_scripts', in addition to looking
2547 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2549 * Tracepoint actions were unified with breakpoint commands. In particular,
2550 there are no longer differences in "info break" output for breakpoints and
2551 tracepoints and the "commands" command can be used for both tracepoints and
2552 regular breakpoints.
2556 ARM Symbian arm*-*-symbianelf*
2558 * D language support.
2559 GDB now supports debugging programs written in the D programming
2562 * GDB now supports the extended ptrace interface for PowerPC which is
2563 available since Linux kernel version 2.6.34. This automatically enables
2564 any hardware breakpoints and additional hardware watchpoints available in
2565 the processor. The old ptrace interface exposes just one hardware
2566 watchpoint and no hardware breakpoints.
2568 * GDB is now able to use the Data Value Compare (DVC) register available on
2569 embedded PowerPC processors to implement in hardware simple watchpoint
2570 conditions of the form:
2572 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2574 This works in native GDB running on Linux kernels with the extended ptrace
2575 interface mentioned above.
2577 *** Changes in GDB 7.1
2581 ** Namespace Support
2583 GDB now supports importing of namespaces in C++. This enables the
2584 user to inspect variables from imported namespaces. Support for
2585 namepace aliasing has also been added. So, if a namespace is
2586 aliased in the current scope (e.g. namepace C=A; ) the user can
2587 print variables using the alias (e.g. (gdb) print C::x).
2591 All known bugs relating to the printing of virtual base class were
2592 fixed. It is now possible to call overloaded static methods using a
2597 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2598 and reinterpret_cast<> are now handled by the C++ expression parser.
2602 Xilinx MicroBlaze microblaze-*-*
2607 Xilinx MicroBlaze microblaze
2610 * Multi-program debugging.
2612 GDB now has support for multi-program (a.k.a. multi-executable or
2613 multi-exec) debugging. This allows for debugging multiple inferiors
2614 simultaneously each running a different program under the same GDB
2615 session. See "Debugging Multiple Inferiors and Programs" in the
2616 manual for more information. This implied some user visible changes
2617 in the multi-inferior support. For example, "info inferiors" now
2618 lists inferiors that are not running yet or that have exited
2619 already. See also "New commands" and "New options" below.
2621 * New tracing features
2623 GDB's tracepoint facility now includes several new features:
2625 ** Trace state variables
2627 GDB tracepoints now include support for trace state variables, which
2628 are variables managed by the target agent during a tracing
2629 experiment. They are useful for tracepoints that trigger each
2630 other, so for instance one tracepoint can count hits in a variable,
2631 and then a second tracepoint has a condition that is true when the
2632 count reaches a particular value. Trace state variables share the
2633 $-syntax of GDB convenience variables, and can appear in both
2634 tracepoint actions and condition expressions. Use the "tvariable"
2635 command to create, and "info tvariables" to view; see "Trace State
2636 Variables" in the manual for more detail.
2640 GDB now includes an option for defining fast tracepoints, which
2641 targets may implement more efficiently, such as by installing a jump
2642 into the target agent rather than a trap instruction. The resulting
2643 speedup can be by two orders of magnitude or more, although the
2644 tradeoff is that some program locations on some target architectures
2645 might not allow fast tracepoint installation, for instance if the
2646 instruction to be replaced is shorter than the jump. To request a
2647 fast tracepoint, use the "ftrace" command, with syntax identical to
2648 the regular trace command.
2650 ** Disconnected tracing
2652 It is now possible to detach GDB from the target while it is running
2653 a trace experiment, then reconnect later to see how the experiment
2654 is going. In addition, a new variable disconnected-tracing lets you
2655 tell the target agent whether to continue running a trace if the
2656 connection is lost unexpectedly.
2660 GDB now has the ability to save the trace buffer into a file, and
2661 then use that file as a target, similarly to you can do with
2662 corefiles. You can select trace frames, print data that was
2663 collected in them, and use tstatus to display the state of the
2664 tracing run at the moment that it was saved. To create a trace
2665 file, use "tsave <filename>", and to use it, do "target tfile
2668 ** Circular trace buffer
2670 You can ask the target agent to handle the trace buffer as a
2671 circular buffer, discarding the oldest trace frames to make room for
2672 newer ones, by setting circular-trace-buffer to on. This feature may
2673 not be available for all target agents.
2678 The disassemble command, when invoked with two arguments, now requires
2679 the arguments to be comma-separated.
2682 The info variables command now displays variable definitions. Files
2683 which only declare a variable are not shown.
2686 The source command is now capable of sourcing Python scripts.
2687 This feature is dependent on the debugger being build with Python
2690 Related to this enhancement is also the introduction of a new command
2691 "set script-extension" (see below).
2693 * New commands (for set/show, see "New options" below)
2695 record save [<FILENAME>]
2696 Save a file (in core file format) containing the process record
2697 execution log for replay debugging at a later time.
2699 record restore <FILENAME>
2700 Restore the process record execution log that was saved at an
2701 earlier time, for replay debugging.
2703 add-inferior [-copies <N>] [-exec <FILENAME>]
2706 clone-inferior [-copies <N>] [ID]
2707 Make a new inferior ready to execute the same program another
2708 inferior has loaded.
2713 maint info program-spaces
2714 List the program spaces loaded into GDB.
2716 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2717 show remote interrupt-sequence
2718 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2719 as the sequence to the remote target in order to interrupt the execution.
2720 Ctrl-C is a default. Some system prefers BREAK which is high level of
2721 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2722 Magic SysRq g. It is BREAK signal and character 'g'.
2724 set remote interrupt-on-connect [on | off]
2725 show remote interrupt-on-connect
2726 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2727 remote target when gdb connects to it. This is needed when you debug
2730 set remotebreak [on | off]
2732 Deprecated. Use "set/show remote interrupt-sequence" instead.
2734 tvariable $NAME [ = EXP ]
2735 Create or modify a trace state variable.
2738 List trace state variables and their values.
2740 delete tvariable $NAME ...
2741 Delete one or more trace state variables.
2744 Evaluate the given expressions without collecting anything into the
2745 trace buffer. (Valid in tracepoint actions only.)
2747 ftrace FN / FILE:LINE / *ADDR
2748 Define a fast tracepoint at the given function, line, or address.
2750 * New expression syntax
2752 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2753 GDB now parses 0b101010 identically with 42.
2757 set follow-exec-mode new|same
2758 show follow-exec-mode
2759 Control whether GDB reuses the same inferior across an exec call or
2760 creates a new one. This is useful to be able to restart the old
2761 executable after the inferior having done an exec call.
2763 set default-collect EXPR, ...
2764 show default-collect
2765 Define a list of expressions to be collected at each tracepoint.
2766 This is a useful way to ensure essential items are not overlooked,
2767 such as registers or a critical global variable.
2769 set disconnected-tracing
2770 show disconnected-tracing
2771 If set to 1, the target is instructed to continue tracing if it
2772 loses its connection to GDB. If 0, the target is to stop tracing
2775 set circular-trace-buffer
2776 show circular-trace-buffer
2777 If set to on, the target is instructed to use a circular trace buffer
2778 and discard the oldest trace frames instead of stopping the trace due
2779 to a full trace buffer. If set to off, the trace stops when the buffer
2780 fills up. Some targets may not support this.
2782 set script-extension off|soft|strict
2783 show script-extension
2784 If set to "off", the debugger does not perform any script language
2785 recognition, and all sourced files are assumed to be GDB scripts.
2786 If set to "soft" (the default), files are sourced according to
2787 filename extension, falling back to GDB scripts if the first
2789 If set to "strict", files are sourced according to filename extension.
2791 set ada trust-PAD-over-XVS on|off
2792 show ada trust-PAD-over-XVS
2793 If off, activate a workaround against a bug in the debugging information
2794 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2795 the GCC sources for more information about the GNAT encoding and
2796 PAD types in particular). It is always safe to set this option to
2797 off, but this introduces a slight performance penalty. The default
2800 * Python API Improvements
2802 ** GDB provides the new class gdb.LazyString. This is useful in
2803 some pretty-printing cases. The new method gdb.Value.lazy_string
2804 provides a simple way to create objects of this type.
2806 ** The fields returned by gdb.Type.fields now have an
2807 `is_base_class' attribute.
2809 ** The new method gdb.Type.range returns the range of an array type.
2811 ** The new method gdb.parse_and_eval can be used to parse and
2812 evaluate an expression.
2814 * New remote packets
2817 Define a trace state variable.
2820 Get the current value of a trace state variable.
2823 Set desired tracing behavior upon disconnection.
2826 Set the trace buffer to be linear or circular.
2829 Get data about the tracepoints currently in use.
2833 Process record now works correctly with hardware watchpoints.
2835 Multiple bug fixes have been made to the mips-irix port, making it
2836 much more reliable. In particular:
2837 - Debugging threaded applications is now possible again. Previously,
2838 GDB would hang while starting the program, or while waiting for
2839 the program to stop at a breakpoint.
2840 - Attaching to a running process no longer hangs.
2841 - An error occurring while loading a core file has been fixed.
2842 - Changing the value of the PC register now works again. This fixes
2843 problems observed when using the "jump" command, or when calling
2844 a function from GDB, or even when assigning a new value to $pc.
2845 - With the "finish" and "return" commands, the return value for functions
2846 returning a small array is now correctly printed.
2847 - It is now possible to break on shared library code which gets executed
2848 during a shared library init phase (code executed while executing
2849 their .init section). Previously, the breakpoint would have no effect.
2850 - GDB is now able to backtrace through the signal handler for
2851 non-threaded programs.
2853 PIE (Position Independent Executable) programs debugging is now supported.
2854 This includes debugging execution of PIC (Position Independent Code) shared
2855 libraries although for that, it should be possible to run such libraries as an
2858 *** Changes in GDB 7.0
2860 * GDB now has an interface for JIT compilation. Applications that
2861 dynamically generate code can create symbol files in memory and register
2862 them with GDB. For users, the feature should work transparently, and
2863 for JIT developers, the interface is documented in the GDB manual in the
2864 "JIT Compilation Interface" chapter.
2866 * Tracepoints may now be conditional. The syntax is as for
2867 breakpoints; either an "if" clause appended to the "trace" command,
2868 or the "condition" command is available. GDB sends the condition to
2869 the target for evaluation using the same bytecode format as is used
2870 for tracepoint actions.
2872 * The disassemble command now supports: an optional /r modifier, print the
2873 raw instructions in hex as well as in symbolic form, and an optional /m
2874 modifier to print mixed source+assembly.
2876 * Process record and replay
2878 In a architecture environment that supports ``process record and
2879 replay'', ``process record and replay'' target can record a log of
2880 the process execution, and replay it with both forward and reverse
2883 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2884 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2885 set execution-direction {forward|reverse}, for targets that support
2888 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2889 feature is available with a native GDB running on kernel version
2892 * GDB now has support for multi-byte and wide character sets on the
2893 target. Strings whose character type is wchar_t, char16_t, or
2894 char32_t are now correctly printed. GDB supports wide- and unicode-
2895 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2896 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2897 `printf'. This feature requires iconv to work properly; if your
2898 system does not have a working iconv, GDB can use GNU libiconv. See
2899 the installation instructions for more information.
2901 * GDB now supports automatic retrieval of shared library files from
2902 remote targets. To use this feature, specify a system root that begins
2903 with the `remote:' prefix, either via the `set sysroot' command or via
2904 the `--with-sysroot' configure-time option.
2906 * "info sharedlibrary" now takes an optional regex of libraries to show,
2907 and it now reports if a shared library has no debugging information.
2909 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2910 now complete on file names.
2912 * When completing in expressions, gdb will attempt to limit
2913 completions to allowable structure or union fields, where appropriate.
2914 For instance, consider:
2916 # struct example { int f1; double f2; };
2917 # struct example variable;
2920 If the user types TAB at the end of this command line, the available
2921 completions will be "f1" and "f2".
2923 * Inlined functions are now supported. They show up in backtraces, and
2924 the "step", "next", and "finish" commands handle them automatically.
2926 * GDB now supports the token-splicing (##) and stringification (#)
2927 operators when expanding macros. It also supports variable-arity
2930 * GDB now supports inspecting extra signal information, exported by
2931 the new $_siginfo convenience variable. The feature is currently
2932 implemented on linux ARM, i386 and amd64.
2934 * GDB can now display the VFP floating point registers and NEON vector
2935 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2936 can provide these registers (requires Linux 2.6.30 or later). Remote
2937 and simulator targets may also provide them.
2939 * New remote packets
2942 Search memory for a sequence of bytes.
2945 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2946 operation over reliable transport links. Use of this packet is
2947 controlled by the `set remote noack-packet' command.
2950 Kill the process with the specified process ID. Use this in preference
2951 to `k' when multiprocess protocol extensions are supported.
2954 Obtains additional operating system information
2958 Read or write additional signal information.
2960 * Removed remote protocol undocumented extension
2962 An undocumented extension to the remote protocol's `S' stop reply
2963 packet that permited the stub to pass a process id was removed.
2964 Remote servers should use the `T' stop reply packet instead.
2966 * GDB now supports multiple function calling conventions according to the
2967 DWARF-2 DW_AT_calling_convention function attribute.
2969 * The SH target utilizes the aforementioned change to distinguish between gcc
2970 and Renesas calling convention. It also adds the new CLI commands
2971 `set/show sh calling-convention'.
2973 * GDB can now read compressed debug sections, as produced by GNU gold
2974 with the --compress-debug-sections=zlib flag.
2976 * 64-bit core files are now supported on AIX.
2978 * Thread switching is now supported on Tru64.
2980 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2981 which will be allocated using malloc later in program execution.
2983 * The qXfer:libraries:read remote procotol packet now allows passing a
2984 list of section offsets.
2986 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2987 conditions handling signals delivered during attach or thread creation
2988 have also been fixed.
2990 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2991 From the user's standpoint, all unqualified instances of True and False
2992 are treated as the standard definitions, regardless of context.
2994 * GDB now parses C++ symbol and type names more flexibly. For
2997 template<typename T> class C { };
3000 GDB will now correctly handle all of:
3002 ptype C<char const *>
3003 ptype C<char const*>
3004 ptype C<const char *>
3005 ptype C<const char*>
3007 * New features in the GDB remote stub, gdbserver
3009 - The "--wrapper" command-line argument tells gdbserver to use a
3010 wrapper program to launch programs for debugging.
3012 - On PowerPC and S/390 targets, it is now possible to use a single
3013 gdbserver executable to debug both 32-bit and 64-bit programs.
3014 (This requires gdbserver itself to be built as a 64-bit executable.)
3016 - gdbserver uses the new noack protocol mode for TCP connections to
3017 reduce communications latency, if also supported and enabled in GDB.
3019 - Support for the sparc64-linux-gnu target is now included in
3022 - The amd64-linux build of gdbserver now supports debugging both
3023 32-bit and 64-bit programs.
3025 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3026 now support hardware watchpoints, and will use them automatically
3031 GDB now has support for scripting using Python. Whether this is
3032 available is determined at configure time.
3034 New GDB commands can now be written in Python.
3036 * Ada tasking support
3038 Ada tasks can now be inspected in GDB. The following commands have
3042 Print the list of Ada tasks.
3044 Print detailed information about task number N.
3046 Print the task number of the current task.
3048 Switch the context of debugging to task number N.
3050 * Support for user-defined prefixed commands. The "define" command can
3051 add new commands to existing prefixes, e.g. "target".
3053 * Multi-inferior, multi-process debugging.
3055 GDB now has generalized support for multi-inferior debugging. See
3056 "Debugging Multiple Inferiors" in the manual for more information.
3057 Although availability still depends on target support, the command
3058 set is more uniform now. The GNU/Linux specific multi-forks support
3059 has been migrated to this new framework. This implied some user
3060 visible changes; see "New commands" and also "Removed commands"
3063 * Target descriptions can now describe the target OS ABI. See the
3064 "Target Description Format" section in the user manual for more
3067 * Target descriptions can now describe "compatible" architectures
3068 to indicate that the target can execute applications for a different
3069 architecture in addition to those for the main target architecture.
3070 See the "Target Description Format" section in the user manual for
3073 * Multi-architecture debugging.
3075 GDB now includes general supports for debugging applications on
3076 hybrid systems that use more than one single processor architecture
3077 at the same time. Each such hybrid architecture still requires
3078 specific support to be added. The only hybrid architecture supported
3079 in this version of GDB is the Cell Broadband Engine.
3081 * GDB now supports integrated debugging of Cell/B.E. applications that
3082 use both the PPU and SPU architectures. To enable support for hybrid
3083 Cell/B.E. debugging, you need to configure GDB to support both the
3084 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3085 --enable-targets configure option.
3087 * Non-stop mode debugging.
3089 For some targets, GDB now supports an optional mode of operation in
3090 which you can examine stopped threads while other threads continue
3091 to execute freely. This is referred to as non-stop mode, with the
3092 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3093 section in the user manual for more information.
3095 To be able to support remote non-stop debugging, a remote stub needs
3096 to implement the non-stop mode remote protocol extensions, as
3097 described in the "Remote Non-Stop" section of the user manual. The
3098 GDB remote stub, gdbserver, has been adjusted to support these
3099 extensions on linux targets.
3101 * New commands (for set/show, see "New options" below)
3103 catch syscall [NAME(S) | NUMBER(S)]
3104 Catch system calls. Arguments, which should be names of system
3105 calls or their numbers, mean catch only those syscalls. Without
3106 arguments, every syscall will be caught. When the inferior issues
3107 any of the specified syscalls, GDB will stop and announce the system
3108 call, both when it is called and when its call returns. This
3109 feature is currently available with a native GDB running on the
3110 Linux Kernel, under the following architectures: x86, x86_64,
3111 PowerPC and PowerPC64.
3113 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3115 Search memory for a sequence of bytes.
3117 maint set python print-stack
3118 maint show python print-stack
3119 Show a stack trace when an error is encountered in a Python script.
3122 Invoke CODE by passing it to the Python interpreter.
3127 These allow macros to be defined, undefined, and listed
3131 Show operating system information about processes.
3134 List the inferiors currently under GDB's control.
3137 Switch focus to inferior number NUM.
3140 Detach from inferior number NUM.
3143 Kill inferior number NUM.
3147 set spu stop-on-load
3148 show spu stop-on-load
3149 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3151 set spu auto-flush-cache
3152 show spu auto-flush-cache
3153 Control whether to automatically flush the software-managed cache
3154 during Cell/B.E. debugging.
3156 set sh calling-convention
3157 show sh calling-convention
3158 Control the calling convention used when calling SH target functions.
3161 show debug timestamp
3162 Control display of timestamps with GDB debugging output.
3164 set disassemble-next-line
3165 show disassemble-next-line
3166 Control display of disassembled source lines or instructions when
3169 set remote noack-packet
3170 show remote noack-packet
3171 Set/show the use of remote protocol QStartNoAckMode packet. See above
3172 under "New remote packets."
3174 set remote query-attached-packet
3175 show remote query-attached-packet
3176 Control use of remote protocol `qAttached' (query-attached) packet.
3178 set remote read-siginfo-object
3179 show remote read-siginfo-object
3180 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3183 set remote write-siginfo-object
3184 show remote write-siginfo-object
3185 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3188 set remote reverse-continue
3189 show remote reverse-continue
3190 Control use of remote protocol 'bc' (reverse-continue) packet.
3192 set remote reverse-step
3193 show remote reverse-step
3194 Control use of remote protocol 'bs' (reverse-step) packet.
3196 set displaced-stepping
3197 show displaced-stepping
3198 Control displaced stepping mode. Displaced stepping is a way to
3199 single-step over breakpoints without removing them from the debuggee.
3200 Also known as "out-of-line single-stepping".
3203 show debug displaced
3204 Control display of debugging info for displaced stepping.
3206 maint set internal-error
3207 maint show internal-error
3208 Control what GDB does when an internal error is detected.
3210 maint set internal-warning
3211 maint show internal-warning
3212 Control what GDB does when an internal warning is detected.
3217 Use a wrapper program to launch programs for debugging.
3219 set multiple-symbols (all|ask|cancel)
3220 show multiple-symbols
3221 The value of this variable can be changed to adjust the debugger behavior
3222 when an expression or a breakpoint location contains an ambiguous symbol
3223 name (an overloaded function name, for instance).
3225 set breakpoint always-inserted
3226 show breakpoint always-inserted
3227 Keep breakpoints always inserted in the target, as opposed to inserting
3228 them when resuming the target, and removing them when the target stops.
3229 This option can improve debugger performance on slow remote targets.
3231 set arm fallback-mode (arm|thumb|auto)
3232 show arm fallback-mode
3233 set arm force-mode (arm|thumb|auto)
3235 These commands control how ARM GDB determines whether instructions
3236 are ARM or Thumb. The default for both settings is auto, which uses
3237 the current CPSR value for instructions without symbols; previous
3238 versions of GDB behaved as if "set arm fallback-mode arm".
3240 set disable-randomization
3241 show disable-randomization
3242 Standalone programs run with the virtual address space randomization enabled
3243 by default on some platforms. This option keeps the addresses stable across
3244 multiple debugging sessions.
3248 Control whether other threads are stopped or not when some thread hits
3253 Requests that asynchronous execution is enabled in the target, if available.
3254 In this case, it's possible to resume target in the background, and interact
3255 with GDB while the target is running. "show target-async" displays the
3256 current state of asynchronous execution of the target.
3258 set target-wide-charset
3259 show target-wide-charset
3260 The target-wide-charset is the name of the character set that GDB
3261 uses when printing characters whose type is wchar_t.
3263 set tcp auto-retry (on|off)
3265 set tcp connect-timeout
3266 show tcp connect-timeout
3267 These commands allow GDB to retry failed TCP connections to a remote stub
3268 with a specified timeout period; this is useful if the stub is launched
3269 in parallel with GDB but may not be ready to accept connections immediately.
3271 set libthread-db-search-path
3272 show libthread-db-search-path
3273 Control list of directories which GDB will search for appropriate
3276 set schedule-multiple (on|off)
3277 show schedule-multiple
3278 Allow GDB to resume all threads of all processes or only threads of
3279 the current process.
3283 Use more aggressive caching for accesses to the stack. This improves
3284 performance of remote debugging (particularly backtraces) without
3285 affecting correctness.
3287 set interactive-mode (on|off|auto)
3288 show interactive-mode
3289 Control whether GDB runs in interactive mode (on) or not (off).
3290 When in interactive mode, GDB waits for the user to answer all
3291 queries. Otherwise, GDB does not wait and assumes the default
3292 answer. When set to auto (the default), GDB determines which
3293 mode to use based on the stdin settings.
3298 For program forks, this is replaced by the new more generic `info
3299 inferiors' command. To list checkpoints, you can still use the
3300 `info checkpoints' command, which was an alias for the `info forks'
3304 Replaced by the new `inferior' command. To switch between
3305 checkpoints, you can still use the `restart' command, which was an
3306 alias for the `fork' command.
3309 This is removed, since some targets don't have a notion of
3310 processes. To switch between processes, you can still use the
3311 `inferior' command using GDB's own inferior number.
3314 For program forks, this is replaced by the new more generic `kill
3315 inferior' command. To delete a checkpoint, you can still use the
3316 `delete checkpoint' command, which was an alias for the `delete
3320 For program forks, this is replaced by the new more generic `detach
3321 inferior' command. To detach a checkpoint, you can still use the
3322 `detach checkpoint' command, which was an alias for the `detach
3325 * New native configurations
3327 x86/x86_64 Darwin i[34567]86-*-darwin*
3329 x86_64 MinGW x86_64-*-mingw*
3333 Lattice Mico32 lm32-*
3334 x86 DICOS i[34567]86-*-dicos*
3335 x86_64 DICOS x86_64-*-dicos*
3338 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3339 (mingw32ce) debugging.
3345 These commands were actually not implemented on any target.
3347 *** Changes in GDB 6.8
3349 * New native configurations
3351 NetBSD/hppa hppa*-*netbsd*
3352 Xtensa GNU/Linux xtensa*-*-linux*
3356 NetBSD/hppa hppa*-*-netbsd*
3357 Xtensa GNU/Lunux xtensa*-*-linux*
3359 * Change in command line behavior -- corefiles vs. process ids.
3361 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3362 attaching to process NUMBER fails, GDB no longer attempts to open a
3363 core file named NUMBER. Attaching to a program using the -c option
3364 is no longer supported. Instead, use the '-p' or '--pid' options.
3366 * GDB can now be built as a native debugger for debugging Windows x86
3367 (mingw32) Portable Executable (PE) programs.
3369 * Pending breakpoints no longer change their number when their address
3372 * GDB now supports breakpoints with multiple locations,
3373 including breakpoints on C++ constructors, inside C++ templates,
3374 and in inlined functions.
3376 * GDB's ability to debug optimized code has been improved. GDB more
3377 accurately identifies function bodies and lexical blocks that occupy
3378 more than one contiguous range of addresses.
3380 * Target descriptions can now describe registers for PowerPC.
3382 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3383 registers on PowerPC targets.
3385 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3386 targets even when the libthread_db library is not available.
3388 * The GDB remote stub, gdbserver, now supports the new file transfer
3389 commands (remote put, remote get, and remote delete).
3391 * The GDB remote stub, gdbserver, now supports run and attach in
3392 extended-remote mode.
3394 * hppa*64*-*-hpux11* target broken
3395 The debugger is unable to start a program and fails with the following
3396 error: "Error trying to get information about dynamic linker".
3397 The gdb-6.7 release is also affected.
3399 * GDB now supports the --enable-targets= configure option to allow
3400 building a single GDB executable that supports multiple remote
3401 target architectures.
3403 * GDB now supports debugging C and C++ programs which use the
3404 Decimal Floating Point extension. In addition, the PowerPC target
3405 now has a set of pseudo-registers to inspect decimal float values
3406 stored in two consecutive float registers.
3408 * The -break-insert MI command can optionally create pending
3411 * Improved support for debugging Ada
3412 Many improvements to the Ada language support have been made. These
3414 - Better support for Ada2005 interface types
3415 - Improved handling of arrays and slices in general
3416 - Better support for Taft-amendment types
3417 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3419 - Improved command completion in Ada
3422 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3427 set print frame-arguments (all|scalars|none)
3428 show print frame-arguments
3429 The value of this variable can be changed to control which argument
3430 values should be printed by the debugger when displaying a frame.
3435 Transfer files to and from a remote target, and delete remote files.
3442 Transfer files to and from a remote target, and delete remote files.
3444 * New remote packets
3451 Open, close, read, write, and delete files on the remote system.
3454 Attach to an existing process on the remote system, in extended-remote
3458 Run a new process on the remote system, in extended-remote mode.
3460 *** Changes in GDB 6.7
3462 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3463 bfd, libiberty and opcodes, as revealed by static analysis donated by
3464 Coverity, Inc. (http://scan.coverity.com).
3466 * When looking up multiply-defined global symbols, GDB will now prefer the
3467 symbol definition in the current shared library if it was built using the
3468 -Bsymbolic linker option.
3470 * When the Text User Interface (TUI) is not configured, GDB will now
3471 recognize the -tui command-line option and print a message that the TUI
3474 * The GDB remote stub, gdbserver, now has lower overhead for high
3475 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3477 * GDB for MIPS targets now autodetects whether a remote target provides
3478 32-bit or 64-bit register values.
3480 * Support for C++ member pointers has been improved.
3482 * GDB now understands XML target descriptions, which specify the
3483 target's overall architecture. GDB can read a description from
3484 a local file or over the remote serial protocol.
3486 * Vectors of single-byte data use a new integer type which is not
3487 automatically displayed as character or string data.
3489 * The /s format now works with the print command. It displays
3490 arrays of single-byte integers and pointers to single-byte integers
3493 * Target descriptions can now describe target-specific registers,
3494 for architectures which have implemented the support (currently
3495 only ARM, M68K, and MIPS).
3497 * GDB and the GDB remote stub, gdbserver, now support the XScale
3500 * The GDB remote stub, gdbserver, has been updated to support
3501 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3502 has been rewritten to use the standard GDB remote protocol.
3504 * GDB can now step into C++ functions which are called through thunks.
3506 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3508 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3509 layout. It also supports a TextSeg= and DataSeg= response when only
3510 segment base addresses (rather than offsets) are available.
3512 * The /i format now outputs any trailing branch delay slot instructions
3513 immediately following the last instruction within the count specified.
3515 * The GDB remote protocol "T" stop reply packet now supports a
3516 "library" response. Combined with the new "qXfer:libraries:read"
3517 packet, this response allows GDB to debug shared libraries on targets
3518 where the operating system manages the list of loaded libraries (e.g.
3519 Windows and SymbianOS).
3521 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3522 (DLLs) on Windows and Windows CE targets.
3524 * GDB now supports a faster verification that a .debug file matches its binary
3525 according to its build-id signature, if the signature is present.
3531 Enable or disable hardware flow control (RTS/CTS) on the serial port
3532 when debugging using remote targets.
3534 set mem inaccessible-by-default
3535 show mem inaccessible-by-default
3536 If the target supplies a memory map, for instance via the remote
3537 protocol's "qXfer:memory-map:read" packet, setting this variable
3538 prevents GDB from accessing memory outside the memory map. This
3539 is useful for targets with memory mapped registers or which react
3540 badly to accesses of unmapped address space.
3542 set breakpoint auto-hw
3543 show breakpoint auto-hw
3544 If the target supplies a memory map, for instance via the remote
3545 protocol's "qXfer:memory-map:read" packet, setting this variable
3546 lets GDB use hardware breakpoints automatically for memory regions
3547 where it can not use software breakpoints. This covers both the
3548 "break" command and internal breakpoints used for other commands
3549 including "next" and "finish".
3552 catch exception unhandled
3553 Stop the program execution when Ada exceptions are raised.
3556 Stop the program execution when an Ada assertion failed.
3560 Set an alternate system root for target files. This is a more
3561 general version of "set solib-absolute-prefix", which is now
3562 an alias to "set sysroot".
3565 Provide extended SPU facility status information. This set of
3566 commands is available only when debugging the Cell/B.E. SPU
3569 * New native configurations
3571 OpenBSD/sh sh*-*openbsd*
3574 unset tdesc filename
3576 Use the specified local file as an XML target description, and do
3577 not query the target for its built-in description.
3581 OpenBSD/sh sh*-*-openbsd*
3582 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3583 Toshiba Media Processor mep-elf
3585 * New remote packets
3588 Ignore the specified signals; pass them directly to the debugged program
3589 without stopping other threads or reporting them to GDB.
3591 qXfer:features:read:
3592 Read an XML target description from the target, which describes its
3597 Read or write contents of an spufs file on the target system. These
3598 packets are available only on the Cell/B.E. SPU architecture.
3600 qXfer:libraries:read:
3601 Report the loaded shared libraries. Combined with new "T" packet
3602 response, this packet allows GDB to debug shared libraries on
3603 targets where the operating system manages the list of loaded
3604 libraries (e.g. Windows and SymbianOS).
3608 Support for these obsolete configurations has been removed.
3616 i[34567]86-*-lynxos*
3617 i[34567]86-*-netware*
3618 i[34567]86-*-sco3.2v5*
3619 i[34567]86-*-sco3.2v4*
3621 i[34567]86-*-sysv4.2*
3624 i[34567]86-*-unixware2*
3625 i[34567]86-*-unixware*
3634 * Other removed features
3641 Various m68k-only ROM monitors.
3648 Various Renesas ROM monitors and debugging interfaces for SH and
3653 Support for a Macraigor serial interface to on-chip debugging.
3654 GDB does not directly support the newer parallel or USB
3659 A debug information format. The predecessor to DWARF 2 and
3660 DWARF 3, which are still supported.
3662 Support for the HP aCC compiler on HP-UX/PA-RISC
3664 SOM-encapsulated symbolic debugging information, automatic
3665 invocation of pxdb, and the aCC custom C++ ABI. This does not
3666 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3667 with aCC can still be debugged on an assembly level.
3669 MIPS ".pdr" sections
3671 A MIPS-specific format used to describe stack frame layout
3672 in debugging information.
3676 GDB could work with an older version of Guile to debug
3677 the interpreter and Scheme programs running in it.
3679 set mips stack-arg-size
3680 set mips saved-gpreg-size
3682 Use "set mips abi" to control parameter passing for MIPS.
3684 *** Changes in GDB 6.6
3689 Cell Broadband Engine SPU spu-elf
3691 * GDB can now be configured as a cross-debugger targeting native Windows
3692 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3693 running on a Windows system over TCP/IP to debug Windows programs.
3695 * The GDB remote stub, gdbserver, has been updated to support Windows and
3696 Cygwin debugging. Both single-threaded and multi-threaded programs are
3699 * The "set trust-readonly-sections" command works again. This command was
3700 broken in GDB 6.3, 6.4, and 6.5.
3702 * The "load" command now supports writing to flash memory, if the remote
3703 stub provides the required support.
3705 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3706 longer requires symbolic debug information (e.g. DWARF-2).
3711 unset substitute-path
3712 show substitute-path
3713 Manage a list of substitution rules that GDB uses to rewrite the name
3714 of the directories where the sources are located. This can be useful
3715 for instance when the sources were moved to a different location
3716 between compilation and debugging.
3720 Print each CLI command as it is executed. Each command is prefixed with
3721 a number of `+' symbols representing the nesting depth.
3722 The source command now has a `-v' option to enable the same feature.
3726 The ARM Demon monitor support (RDP protocol, "target rdp").
3728 Kernel Object Display, an embedded debugging feature which only worked with
3729 an obsolete version of Cisco IOS.
3731 The 'set download-write-size' and 'show download-write-size' commands.
3733 * New remote packets
3736 Tell a stub about GDB client features, and request remote target features.
3737 The first feature implemented is PacketSize, which allows the target to
3738 specify the size of packets it can handle - to minimize the number of
3739 packets required and improve performance when connected to a remote
3743 Fetch an OS auxilliary vector from the remote stub. This packet is a
3744 more efficient replacement for qPart:auxv:read.
3746 qXfer:memory-map:read:
3747 Fetch a memory map from the remote stub, including information about
3748 RAM, ROM, and flash memory devices.
3753 Erase and program a flash memory device.
3755 * Removed remote packets
3758 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3759 used it, and only gdbserver implemented it.
3761 *** Changes in GDB 6.5
3765 Renesas M32C/M16C m32c-elf
3767 Morpho Technologies ms1 ms1-elf
3771 init-if-undefined Initialize a convenience variable, but
3772 only if it doesn't already have a value.
3774 The following commands are presently only implemented for native GNU/Linux:
3776 checkpoint Save a snapshot of the program state.
3778 restart <n> Return the program state to a
3779 previously saved state.
3781 info checkpoints List currently saved checkpoints.
3783 delete-checkpoint <n> Delete a previously saved checkpoint.
3785 set|show detach-on-fork Tell gdb whether to detach from a newly
3786 forked process, or to keep debugging it.
3788 info forks List forks of the user program that
3789 are available to be debugged.
3791 fork <n> Switch to debugging one of several
3792 forks of the user program that are
3793 available to be debugged.
3795 delete-fork <n> Delete a fork from the list of forks
3796 that are available to be debugged (and
3797 kill the forked process).
3799 detach-fork <n> Delete a fork from the list of forks
3800 that are available to be debugged (and
3801 allow the process to continue).
3805 Morpho Technologies ms2 ms1-elf
3807 * Improved Windows host support
3809 GDB now builds as a cross debugger hosted on i686-mingw32, including
3810 native console support, and remote communications using either
3811 network sockets or serial ports.
3813 * Improved Modula-2 language support
3815 GDB can now print most types in the Modula-2 syntax. This includes:
3816 basic types, set types, record types, enumerated types, range types,
3817 pointer types and ARRAY types. Procedure var parameters are correctly
3818 printed and hexadecimal addresses and character constants are also
3819 written in the Modula-2 syntax. Best results can be obtained by using
3820 GNU Modula-2 together with the -gdwarf-2 command line option.
3824 The ARM rdi-share module.
3826 The Netware NLM debug server.
3828 *** Changes in GDB 6.4
3830 * New native configurations
3832 OpenBSD/arm arm*-*-openbsd*
3833 OpenBSD/mips64 mips64-*-openbsd*
3837 Morpho Technologies ms1 ms1-elf
3839 * New command line options
3841 --batch-silent As for --batch, but totally silent.
3842 --return-child-result The debugger will exist with the same value
3843 the child (debugged) program exited with.
3844 --eval-command COMMAND, -ex COMMAND
3845 Execute a single GDB CLI command. This may be
3846 specified multiple times and in conjunction
3847 with the --command (-x) option.
3849 * Deprecated commands removed
3851 The following commands, that were deprecated in 2000, have been
3855 set|show arm disassembly-flavor set|show arm disassembler
3856 othernames set arm disassembler
3857 set|show remotedebug set|show debug remote
3858 set|show archdebug set|show debug arch
3859 set|show eventdebug set|show debug event
3862 * New BSD user-level threads support
3864 It is now possible to debug programs using the user-level threads
3865 library on OpenBSD and FreeBSD. Currently supported (target)
3868 FreeBSD/amd64 x86_64-*-freebsd*
3869 FreeBSD/i386 i386-*-freebsd*
3870 OpenBSD/i386 i386-*-openbsd*
3872 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3873 are not yet supported.
3875 * New support for Matsushita MN10300 w/sim added
3876 (Work in progress). mn10300-elf.
3878 * REMOVED configurations and files
3880 VxWorks and the XDR protocol *-*-vxworks
3881 Motorola MCORE mcore-*-*
3882 National Semiconductor NS32000 ns32k-*-*
3884 * New "set print array-indexes" command
3886 After turning this setting "on", GDB prints the index of each element
3887 when displaying arrays. The default is "off" to preserve the previous
3890 * VAX floating point support
3892 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3894 * User-defined command support
3896 In addition to using $arg0..$arg9 for argument passing, it is now possible
3897 to use $argc to determine now many arguments have been passed. See the
3898 section on user-defined commands in the user manual for more information.
3900 *** Changes in GDB 6.3:
3902 * New command line option
3904 GDB now accepts -l followed by a number to set the timeout for remote
3907 * GDB works with GCC -feliminate-dwarf2-dups
3909 GDB now supports a more compact representation of DWARF-2 debug
3910 information using DW_FORM_ref_addr references. These are produced
3911 by GCC with the option -feliminate-dwarf2-dups and also by some
3912 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3913 to use -feliminate-dwarf2-dups.
3915 * Internationalization
3917 When supported by the host system, GDB will be built with
3918 internationalization (libintl). The task of marking up the sources is
3919 continued, we're looking forward to our first translation.
3923 Initial support for debugging programs compiled with the GNAT
3924 implementation of the Ada programming language has been integrated
3925 into GDB. In this release, support is limited to expression evaluation.
3927 * New native configurations
3929 GNU/Linux/m32r m32r-*-linux-gnu
3933 GDB's remote protocol now includes support for the 'p' packet. This
3934 packet is used to fetch individual registers from a remote inferior.
3936 * END-OF-LIFE registers[] compatibility module
3938 GDB's internal register infrastructure has been completely rewritten.
3939 The new infrastructure making possible the implementation of key new
3940 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3943 GDB 6.3 will be the last release to include the the registers[]
3944 compatibility module that allowed out-of-date configurations to
3945 continue to work. This change directly impacts the following
3955 powerpc bdm protocol
3957 Unless there is activity to revive these configurations, they will be
3958 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3960 * OBSOLETE configurations and files
3962 Configurations that have been declared obsolete in this release have
3963 been commented out. Unless there is activity to revive these
3964 configurations, the next release of GDB will have their sources
3965 permanently REMOVED.
3974 *** Changes in GDB 6.2.1:
3976 * MIPS `break main; run' gave an heuristic-fence-post warning
3978 When attempting to run even a simple program, a warning about
3979 heuristic-fence-post being hit would be reported. This problem has
3982 * MIPS IRIX 'long double' crashed GDB
3984 When examining a long double variable, GDB would get a segmentation
3985 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3986 IRIX long double values).
3990 A bug in the VAX stack code was causing problems with the "next"
3991 command. This problem has been fixed.
3993 *** Changes in GDB 6.2:
3995 * Fix for ``many threads''
3997 On GNU/Linux systems that use the NPTL threads library, a program
3998 rapidly creating and deleting threads would confuse GDB leading to the
4001 ptrace: No such process.
4002 thread_db_get_info: cannot get thread info: generic error
4004 This problem has been fixed.
4006 * "-async" and "-noasync" options removed.
4008 Support for the broken "-noasync" option has been removed (it caused
4011 * New ``start'' command.
4013 This command runs the program until the begining of the main procedure.
4015 * New BSD Kernel Data Access Library (libkvm) interface
4017 Using ``target kvm'' it is now possible to debug kernel core dumps and
4018 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4019 platforms. Currently supported (native-only) configurations are:
4021 FreeBSD/amd64 x86_64-*-freebsd*
4022 FreeBSD/i386 i?86-*-freebsd*
4023 NetBSD/i386 i?86-*-netbsd*
4024 NetBSD/m68k m68*-*-netbsd*
4025 NetBSD/sparc sparc-*-netbsd*
4026 OpenBSD/amd64 x86_64-*-openbsd*
4027 OpenBSD/i386 i?86-*-openbsd*
4028 OpenBSD/m68k m68*-openbsd*
4029 OpenBSD/sparc sparc-*-openbsd*
4031 * Signal trampoline code overhauled
4033 Many generic problems with GDB's signal handling code have been fixed.
4034 These include: backtraces through non-contiguous stacks; recognition
4035 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4036 call; backtrace through a signal trampoline; step into and out of
4037 signal handlers; and single-stepping in the signal trampoline.
4039 Please note that kernel bugs are a limiting factor here. These
4040 features have been shown to work on an s390 GNU/Linux system that
4041 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4043 * Cygwin support for DWARF 2 added.
4045 * New native configurations
4047 GNU/Linux/hppa hppa*-*-linux*
4048 OpenBSD/hppa hppa*-*-openbsd*
4049 OpenBSD/m68k m68*-*-openbsd*
4050 OpenBSD/m88k m88*-*-openbsd*
4051 OpenBSD/powerpc powerpc-*-openbsd*
4052 NetBSD/vax vax-*-netbsd*
4053 OpenBSD/vax vax-*-openbsd*
4055 * END-OF-LIFE frame compatibility module
4057 GDB's internal frame infrastructure has been completely rewritten.
4058 The new infrastructure making it possible to support key new features
4059 including DWARF 2 Call Frame Information. To aid in the task of
4060 migrating old configurations to this new infrastructure, a
4061 compatibility module, that allowed old configurations to continue to
4062 work, was also included.
4064 GDB 6.2 will be the last release to include this frame compatibility
4065 module. This change directly impacts the following configurations:
4075 Unless there is activity to revive these configurations, they will be
4076 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4078 * REMOVED configurations and files
4080 Sun 3, running SunOS 3 m68*-*-sunos3*
4081 Sun 3, running SunOS 4 m68*-*-sunos4*
4082 Sun 2, running SunOS 3 m68000-*-sunos3*
4083 Sun 2, running SunOS 4 m68000-*-sunos4*
4084 Motorola 680x0 running LynxOS m68*-*-lynxos*
4085 AT&T 3b1/Unix pc m68*-att-*
4086 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4087 decstation mips-dec-* mips-little-*
4088 riscos mips-*-riscos* mips-*-sysv*
4089 sonymips mips-sony-*
4090 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4092 *** Changes in GDB 6.1.1:
4094 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4096 The TUI (Text-mode User Interface) is now built as part of a default
4097 GDB configuration. It is enabled by either selecting the TUI with the
4098 command line option "-i=tui" or by running the separate "gdbtui"
4099 program. For more information on the TUI, see the manual "Debugging
4102 * Pending breakpoint support (also included in GDB 6.1)
4104 Support has been added to allow you to specify breakpoints in shared
4105 libraries that have not yet been loaded. If a breakpoint location
4106 cannot be found, and the "breakpoint pending" option is set to auto,
4107 GDB queries you if you wish to make the breakpoint pending on a future
4108 shared-library load. If and when GDB resolves the breakpoint symbol,
4109 the pending breakpoint is removed as one or more regular breakpoints
4112 Pending breakpoints are very useful for GCJ Java debugging.
4114 * Fixed ISO-C build problems
4116 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4117 non ISO-C code that stopped them being built using a more strict ISO-C
4118 compiler (e.g., IBM's C compiler).
4120 * Fixed build problem on IRIX 5
4122 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4123 wasn't able to compile compile on an IRIX 5 system.
4125 * Added execute permission to gdb/gdbserver/configure
4127 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4128 permission. This bug would cause configure to fail on a number of
4129 systems (Solaris, IRIX). Ref: server/519.
4131 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4133 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4134 has been updated to use constant array sizes.
4136 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4138 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4139 its generated DWARF Call Frame Info. This encoding was causing GDB to
4140 panic, that panic has been fixed. Ref: gdb/1628.
4142 * Fixed a problem when examining parameters in shared library code.
4144 When examining parameters in optimized shared library code generated
4145 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4146 not available''. GDB now correctly displays the variable's value.
4148 *** Changes in GDB 6.1:
4150 * Removed --with-mmalloc
4152 Support for the mmalloc memory manager has been removed, as it
4153 conflicted with the internal gdb byte cache.
4155 * Changes in AMD64 configurations
4157 The AMD64 target now includes the %cs and %ss registers. As a result
4158 the AMD64 remote protocol has changed; this affects the floating-point
4159 and SSE registers. If you rely on those registers for your debugging,
4160 you should upgrade gdbserver on the remote side.
4162 * Revised SPARC target
4164 The SPARC target has been completely revised, incorporating the
4165 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4166 support for LynxOS and SunOS 4 has been dropped. Calling functions
4167 from within GDB on operating systems with a non-executable stack
4168 (Solaris, OpenBSD) now works.
4172 GDB has a new C++ demangler which does a better job on the mangled
4173 names generated by current versions of g++. It also runs faster, so
4174 with this and other changes gdb should now start faster on large C++
4177 * DWARF 2 Location Expressions
4179 GDB support for location expressions has been extended to support function
4180 arguments and frame bases. Older versions of GDB could crash when they
4183 * C++ nested types and namespaces
4185 GDB's support for nested types and namespaces in C++ has been
4186 improved, especially if you use the DWARF 2 debugging format. (This
4187 is the default for recent versions of GCC on most platforms.)
4188 Specifically, if you have a class "Inner" defined within a class or
4189 namespace "Outer", then GDB realizes that the class's name is
4190 "Outer::Inner", not simply "Inner". This should greatly reduce the
4191 frequency of complaints about not finding RTTI symbols. In addition,
4192 if you are stopped at inside of a function defined within a namespace,
4193 GDB modifies its name lookup accordingly.
4195 * New native configurations
4197 NetBSD/amd64 x86_64-*-netbsd*
4198 OpenBSD/amd64 x86_64-*-openbsd*
4199 OpenBSD/alpha alpha*-*-openbsd*
4200 OpenBSD/sparc sparc-*-openbsd*
4201 OpenBSD/sparc64 sparc64-*-openbsd*
4203 * New debugging protocols
4205 M32R with SDI protocol m32r-*-elf*
4207 * "set prompt-escape-char" command deleted.
4209 The command "set prompt-escape-char" has been deleted. This command,
4210 and its very obscure effet on GDB's prompt, was never documented,
4211 tested, nor mentioned in the NEWS file.
4213 * OBSOLETE configurations and files
4215 Configurations that have been declared obsolete in this release have
4216 been commented out. Unless there is activity to revive these
4217 configurations, the next release of GDB will have their sources
4218 permanently REMOVED.
4220 Sun 3, running SunOS 3 m68*-*-sunos3*
4221 Sun 3, running SunOS 4 m68*-*-sunos4*
4222 Sun 2, running SunOS 3 m68000-*-sunos3*
4223 Sun 2, running SunOS 4 m68000-*-sunos4*
4224 Motorola 680x0 running LynxOS m68*-*-lynxos*
4225 AT&T 3b1/Unix pc m68*-att-*
4226 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4227 decstation mips-dec-* mips-little-*
4228 riscos mips-*-riscos* mips-*-sysv*
4229 sonymips mips-sony-*
4230 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4232 * REMOVED configurations and files
4234 SGI Irix-4.x mips-sgi-irix4 or iris4
4235 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4236 Z8000 simulator z8k-zilog-none or z8ksim
4237 Matsushita MN10200 w/simulator mn10200-*-*
4238 H8/500 simulator h8500-hitachi-hms or h8500hms
4239 HP/PA running BSD hppa*-*-bsd*
4240 HP/PA running OSF/1 hppa*-*-osf*
4241 HP/PA Pro target hppa*-*-pro*
4242 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4243 386BSD i[3456]86-*-bsd*
4244 Sequent family i[3456]86-sequent-sysv4*
4245 i[3456]86-sequent-sysv*
4246 i[3456]86-sequent-bsd*
4247 SPARC running LynxOS sparc-*-lynxos*
4248 SPARC running SunOS 4 sparc-*-sunos4*
4249 Tsqware Sparclet sparclet-*-*
4250 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4252 *** Changes in GDB 6.0:
4256 Support for debugging the Objective-C programming language has been
4257 integrated into GDB.
4259 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4261 DWARF 2's Call Frame Information makes available compiler generated
4262 information that more exactly describes the program's run-time stack.
4263 By using this information, GDB is able to provide more robust stack
4266 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4267 have been updated to use a new backtrace mechanism which includes
4268 DWARF 2 CFI support.
4272 GDB's remote protocol has been extended to include support for hosted
4273 file I/O (where the remote target uses GDB's file system). See GDB's
4274 remote protocol documentation for details.
4276 * All targets using the new architecture framework.
4278 All of GDB's targets have been updated to use the new internal
4279 architecture framework. The way is now open for future GDB releases
4280 to include cross-architecture native debugging support (i386 on amd64,
4283 * GNU/Linux's Thread Local Storage (TLS)
4285 GDB now includes support for for the GNU/Linux implementation of
4286 per-thread variables.
4288 * GNU/Linux's Native POSIX Thread Library (NPTL)
4290 GDB's thread code has been updated to work with either the new
4291 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4293 * Separate debug info.
4295 GDB, in conjunction with BINUTILS, now supports a mechanism for
4296 automatically loading debug information from a separate file. Instead
4297 of shipping full debug and non-debug versions of system libraries,
4298 system integrators can now instead ship just the stripped libraries
4299 and optional debug files.
4301 * DWARF 2 Location Expressions
4303 DWARF 2 Location Expressions allow the compiler to more completely
4304 describe the location of variables (even in optimized code) to the
4307 GDB now includes preliminary support for location expressions (support
4308 for DW_OP_piece is still missing).
4312 A number of long standing bugs that caused GDB to die while starting a
4313 Java application have been fixed. GDB's Java support is now
4314 considered "useable".
4316 * GNU/Linux support for fork, vfork, and exec.
4318 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4319 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4322 * GDB supports logging output to a file
4324 There are two new commands, "set logging" and "show logging", which can be
4325 used to capture GDB's output to a file.
4327 * The meaning of "detach" has changed for gdbserver
4329 The "detach" command will now resume the application, as documented. To
4330 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4333 * d10v, m68hc11 `regs' command deprecated
4335 The `info registers' command has been updated so that it displays the
4336 registers using a format identical to the old `regs' command.
4340 A new command, "maint set profile on/off", has been added. This command can
4341 be used to enable or disable profiling while running GDB, to profile a
4342 session or a set of commands. In addition there is a new configure switch,
4343 "--enable-profiling", which will cause GDB to be compiled with profiling
4344 data, for more informative profiling results.
4346 * Default MI syntax changed to "mi2".
4348 The default MI (machine interface) syntax, enabled by the command line
4349 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4350 "mi1", can be enabled by specifying the option "-i=mi1".
4352 Support for the original "mi0" syntax (included in GDB 5.0) has been
4355 Fix for gdb/192: removed extraneous space when displaying frame level.
4356 Fix for gdb/672: update changelist is now output in mi list format.
4357 Fix for gdb/702: a -var-assign that updates the value now shows up
4358 in a subsequent -var-update.
4360 * New native configurations.
4362 FreeBSD/amd64 x86_64-*-freebsd*
4364 * Multi-arched targets.
4366 HP/PA HPUX11 hppa*-*-hpux*
4367 Renesas M32R/D w/simulator m32r-*-elf*
4369 * OBSOLETE configurations and files
4371 Configurations that have been declared obsolete in this release have
4372 been commented out. Unless there is activity to revive these
4373 configurations, the next release of GDB will have their sources
4374 permanently REMOVED.
4376 Z8000 simulator z8k-zilog-none or z8ksim
4377 Matsushita MN10200 w/simulator mn10200-*-*
4378 H8/500 simulator h8500-hitachi-hms or h8500hms
4379 HP/PA running BSD hppa*-*-bsd*
4380 HP/PA running OSF/1 hppa*-*-osf*
4381 HP/PA Pro target hppa*-*-pro*
4382 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4383 Sequent family i[3456]86-sequent-sysv4*
4384 i[3456]86-sequent-sysv*
4385 i[3456]86-sequent-bsd*
4386 Tsqware Sparclet sparclet-*-*
4387 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4389 * REMOVED configurations and files
4392 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4393 IBM AIX PS/2 i[3456]86-*-aix
4394 i386 running Mach 3.0 i[3456]86-*-mach3*
4395 i386 running Mach i[3456]86-*-mach*
4396 i386 running OSF/1 i[3456]86-*osf1mk*
4397 HP/Apollo 68k Family m68*-apollo*-sysv*,
4399 m68*-hp-bsd*, m68*-hp-hpux*
4400 Argonaut Risc Chip (ARC) arc-*-*
4401 Mitsubishi D30V d30v-*-*
4402 Fujitsu FR30 fr30-*-elf*
4403 OS/9000 i[34]86-*-os9k
4404 I960 with MON960 i960-*-coff
4406 * MIPS $fp behavior changed
4408 The convenience variable $fp, for the MIPS, now consistently returns
4409 the address of the current frame's base. Previously, depending on the
4410 context, $fp could refer to either $sp or the current frame's base
4411 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4412 The GNU Source-Level Debugger''.
4414 *** Changes in GDB 5.3:
4416 * GNU/Linux shared library multi-threaded performance improved.
4418 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4419 `/proc', in preference to `ptrace' for memory reads. This may result
4420 in an improvement in the start-up time of multi-threaded, shared
4421 library applications when run under GDB. One GDB user writes: ``loads
4422 shared libs like mad''.
4424 * ``gdbserver'' now supports multi-threaded applications on some targets
4426 Support for debugging multi-threaded applications which use
4427 the GNU/Linux LinuxThreads package has been added for
4428 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4429 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4431 * GDB now supports C/C++ preprocessor macros.
4433 GDB now expands preprocessor macro invocations in C/C++ expressions,
4434 and provides various commands for showing macro definitions and how
4437 The new command `macro expand EXPRESSION' expands any macro
4438 invocations in expression, and shows the result.
4440 The new command `show macro MACRO-NAME' shows the definition of the
4441 macro named MACRO-NAME, and where it was defined.
4443 Most compilers don't include information about macros in the debugging
4444 information by default. In GCC 3.1, for example, you need to compile
4445 your program with the options `-gdwarf-2 -g3'. If the macro
4446 information is present in the executable, GDB will read it.
4448 * Multi-arched targets.
4450 DEC Alpha (partial) alpha*-*-*
4451 DEC VAX (partial) vax-*-*
4453 National Semiconductor NS32000 (partial) ns32k-*-*
4454 Motorola 68000 (partial) m68k-*-*
4455 Motorola MCORE mcore-*-*
4459 Fujitsu FRV architecture added by Red Hat frv*-*-*
4462 * New native configurations
4464 Alpha NetBSD alpha*-*-netbsd*
4465 SH NetBSD sh*-*-netbsdelf*
4466 MIPS NetBSD mips*-*-netbsd*
4467 UltraSPARC NetBSD sparc64-*-netbsd*
4469 * OBSOLETE configurations and files
4471 Configurations that have been declared obsolete in this release have
4472 been commented out. Unless there is activity to revive these
4473 configurations, the next release of GDB will have their sources
4474 permanently REMOVED.
4476 Mitsubishi D30V d30v-*-*
4477 OS/9000 i[34]86-*-os9k
4478 IBM AIX PS/2 i[3456]86-*-aix
4479 Fujitsu FR30 fr30-*-elf*
4480 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4481 Argonaut Risc Chip (ARC) arc-*-*
4482 i386 running Mach 3.0 i[3456]86-*-mach3*
4483 i386 running Mach i[3456]86-*-mach*
4484 i386 running OSF/1 i[3456]86-*osf1mk*
4485 HP/Apollo 68k Family m68*-apollo*-sysv*,
4487 m68*-hp-bsd*, m68*-hp-hpux*
4488 I960 with MON960 i960-*-coff
4490 * OBSOLETE languages
4492 CHILL, a Pascal like language used by telecommunications companies.
4494 * REMOVED configurations and files
4496 AMD 29k family via UDI a29k-amd-udi, udi29k
4497 A29K VxWorks a29k-*-vxworks
4498 AMD 29000 embedded, using EBMON a29k-none-none
4499 AMD 29000 embedded with COFF a29k-none-coff
4500 AMD 29000 embedded with a.out a29k-none-aout
4502 testsuite/gdb.hp/gdb.threads-hp/ directory
4504 * New command "set max-user-call-depth <nnn>"
4506 This command allows the user to limit the call depth of user-defined
4507 commands. The default is 1024.
4509 * Changes in FreeBSD/i386 native debugging.
4511 Support for the "generate-core-file" has been added.
4513 * New commands "dump", "append", and "restore".
4515 These commands allow data to be copied from target memory
4516 to a bfd-format or binary file (dump and append), and back
4517 from a file into memory (restore).
4519 * Improved "next/step" support on multi-processor Alpha Tru64.
4521 The previous single-step mechanism could cause unpredictable problems,
4522 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4523 of a software single-step mechanism prevents this.
4525 *** Changes in GDB 5.2.1:
4533 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4534 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4535 Fix, by Joel Brobecker imported from mainline.
4537 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4538 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4539 Fix, by Fred Fish, imported from mainline.
4541 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4542 Surprisingly enough, it works now.
4543 By Michal Ludvig, imported from mainline.
4545 i386 hardware watchpoint support:
4546 avoid misses on second run for some targets.
4547 By Pierre Muller, imported from mainline.
4549 *** Changes in GDB 5.2:
4551 * New command "set trust-readonly-sections on[off]".
4553 This command is a hint that tells gdb that read-only sections
4554 really are read-only (ie. that their contents will not change).
4555 In this mode, gdb will go to the object file rather than the
4556 target to read memory from read-only sections (such as ".text").
4557 This can be a significant performance improvement on some
4558 (notably embedded) targets.
4560 * New command "generate-core-file" (or "gcore").
4562 This new gdb command allows the user to drop a core file of the child
4563 process state at any time. So far it's been implemented only for
4564 GNU/Linux and Solaris, but should be relatively easily ported to other
4565 hosts. Argument is core file name (defaults to core.<pid>).
4567 * New command line option
4569 GDB now accepts --pid or -p followed by a process id.
4571 * Change in command line behavior -- corefiles vs. process ids.
4573 There is a subtle behavior in the way in which GDB handles
4574 command line arguments. The first non-flag argument is always
4575 a program to debug, but the second non-flag argument may either
4576 be a corefile or a process id. Previously, GDB would attempt to
4577 open the second argument as a corefile, and if that failed, would
4578 issue a superfluous error message and then attempt to attach it as
4579 a process. Now, if the second argument begins with a non-digit,
4580 it will be treated as a corefile. If it begins with a digit,
4581 GDB will attempt to attach it as a process, and if no such process
4582 is found, will then attempt to open it as a corefile.
4584 * Changes in ARM configurations.
4586 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4587 configuration is fully multi-arch.
4589 * New native configurations
4591 ARM NetBSD arm*-*-netbsd*
4592 x86 OpenBSD i[3456]86-*-openbsd*
4593 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4594 Sparc64 running FreeBSD sparc64-*-freebsd*
4598 Sanyo XStormy16 xstormy16-elf
4600 * OBSOLETE configurations and files
4602 Configurations that have been declared obsolete in this release have
4603 been commented out. Unless there is activity to revive these
4604 configurations, the next release of GDB will have their sources
4605 permanently REMOVED.
4607 AMD 29k family via UDI a29k-amd-udi, udi29k
4608 A29K VxWorks a29k-*-vxworks
4609 AMD 29000 embedded, using EBMON a29k-none-none
4610 AMD 29000 embedded with COFF a29k-none-coff
4611 AMD 29000 embedded with a.out a29k-none-aout
4613 testsuite/gdb.hp/gdb.threads-hp/ directory
4615 * REMOVED configurations and files
4617 TI TMS320C80 tic80-*-*
4619 PowerPC Solaris powerpcle-*-solaris*
4620 PowerPC Windows NT powerpcle-*-cygwin32
4621 PowerPC Netware powerpc-*-netware*
4622 Harris/CXUX m88k m88*-harris-cxux*
4623 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4624 ns32k-utek-sysv* ns32k-utek-*
4625 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4626 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4627 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4628 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4629 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4631 * Changes to command line processing
4633 The new `--args' feature can be used to specify command-line arguments
4634 for the inferior from gdb's command line.
4636 * Changes to key bindings
4638 There is a new `operate-and-get-next' function bound to `C-o'.
4640 *** Changes in GDB 5.1.1
4642 Fix compile problem on DJGPP.
4644 Fix a problem with floating-point registers on the i386 being
4647 Fix to stop GDB crashing on .debug_str debug info.
4649 Numerous documentation fixes.
4651 Numerous testsuite fixes.
4653 *** Changes in GDB 5.1:
4655 * New native configurations
4657 Alpha FreeBSD alpha*-*-freebsd*
4658 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4659 MIPS GNU/Linux mips*-*-linux*
4660 MIPS SGI Irix 6.x mips*-sgi-irix6*
4661 ia64 AIX ia64-*-aix*
4662 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4666 Motorola 68HC11 and 68HC12 m68hc11-elf
4668 UltraSparc running GNU/Linux sparc64-*-linux*
4670 * OBSOLETE configurations and files
4672 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4673 Harris/CXUX m88k m88*-harris-cxux*
4674 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4675 ns32k-utek-sysv* ns32k-utek-*
4676 TI TMS320C80 tic80-*-*
4678 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4679 PowerPC Solaris powerpcle-*-solaris*
4680 PowerPC Windows NT powerpcle-*-cygwin32
4681 PowerPC Netware powerpc-*-netware*
4682 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4683 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4684 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4685 Apple Macintosh (MPW) host N/A
4687 stuff.c (Program to stuff files into a specially prepared space in kdb)
4688 kdb-start.c (Main loop for the standalone kernel debugger)
4690 Configurations that have been declared obsolete in this release have
4691 been commented out. Unless there is activity to revive these
4692 configurations, the next release of GDB will have their sources
4693 permanently REMOVED.
4695 * REMOVED configurations and files
4697 Altos 3068 m68*-altos-*
4698 Convex c1-*-*, c2-*-*
4700 ARM RISCix arm-*-* (as host)
4704 * GDB has been converted to ISO C.
4706 GDB's source code has been converted to ISO C. In particular, the
4707 sources are fully protoized, and rely on standard headers being
4712 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4714 * The MI enabled by default.
4716 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4717 revised and enabled by default. Packages which use GDB as a debugging
4718 engine behind a UI or another front end are encouraged to switch to
4719 using the GDB/MI interface, instead of the old annotations interface
4720 which is now deprecated.
4722 * Support for debugging Pascal programs.
4724 GDB now includes support for debugging Pascal programs. The following
4725 main features are supported:
4727 - Pascal-specific data types such as sets;
4729 - automatic recognition of Pascal sources based on file-name
4732 - Pascal-style display of data types, variables, and functions;
4734 - a Pascal expression parser.
4736 However, some important features are not yet supported.
4738 - Pascal string operations are not supported at all;
4740 - there are some problems with boolean types;
4742 - Pascal type hexadecimal constants are not supported
4743 because they conflict with the internal variables format;
4745 - support for Pascal objects and classes is not full yet;
4747 - unlike Pascal, GDB is case-sensitive for symbol names.
4749 * Changes in completion.
4751 Commands such as `shell', `run' and `set args', which pass arguments
4752 to inferior programs, now complete on file names, similar to what
4753 users expect at the shell prompt.
4755 Commands which accept locations, such as `disassemble', `print',
4756 `breakpoint', `until', etc. now complete on filenames as well as
4757 program symbols. Thus, if you type "break foob TAB", and the source
4758 files linked into the programs include `foobar.c', that file name will
4759 be one of the candidates for completion. However, file names are not
4760 considered for completion after you typed a colon that delimits a file
4761 name from a name of a function in that file, as in "break foo.c:bar".
4763 `set demangle-style' completes on available demangling styles.
4765 * New platform-independent commands:
4767 It is now possible to define a post-hook for a command as well as a
4768 hook that runs before the command. For more details, see the
4769 documentation of `hookpost' in the GDB manual.
4771 * Changes in GNU/Linux native debugging.
4773 Support for debugging multi-threaded programs has been completely
4774 revised for all platforms except m68k and sparc. You can now debug as
4775 many threads as your system allows you to have.
4777 Attach/detach is supported for multi-threaded programs.
4779 Support for SSE registers was added for x86. This doesn't work for
4780 multi-threaded programs though.
4782 * Changes in MIPS configurations.
4784 Multi-arch support is enabled for all MIPS configurations.
4786 GDB can now be built as native debugger on SGI Irix 6.x systems for
4787 debugging n32 executables. (Debugging 64-bit executables is not yet
4790 * Unified support for hardware watchpoints in all x86 configurations.
4792 Most (if not all) native x86 configurations support hardware-assisted
4793 breakpoints and watchpoints in a unified manner. This support
4794 implements debug register sharing between watchpoints, which allows to
4795 put a virtually infinite number of watchpoints on the same address,
4796 and also supports watching regions up to 16 bytes with several debug
4799 The new maintenance command `maintenance show-debug-regs' toggles
4800 debugging print-outs in functions that insert, remove, and test
4801 watchpoints and hardware breakpoints.
4803 * Changes in the DJGPP native configuration.
4805 New command ``info dos sysinfo'' displays assorted information about
4806 the CPU, OS, memory, and DPMI server.
4808 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4809 display information about segment descriptors stored in GDT, LDT, and
4812 New commands ``info dos pde'' and ``info dos pte'' display entries
4813 from Page Directory and Page Tables (for now works with CWSDPMI only).
4814 New command ``info dos address-pte'' displays the Page Table entry for
4815 a given linear address.
4817 GDB can now pass command lines longer than 126 characters to the
4818 program being debugged (requires an update to the libdbg.a library
4819 which is part of the DJGPP development kit).
4821 DWARF2 debug info is now supported.
4823 It is now possible to `step' and `next' through calls to `longjmp'.
4825 * Changes in documentation.
4827 All GDB documentation was converted to GFDL, the GNU Free
4828 Documentation License.
4830 Tracepoints-related commands are now fully documented in the GDB
4833 TUI, the Text-mode User Interface, is now documented in the manual.
4835 Tracepoints-related commands are now fully documented in the GDB
4838 The "GDB Internals" manual now has an index. It also includes
4839 documentation of `ui_out' functions, GDB coding standards, x86
4840 hardware watchpoints, and memory region attributes.
4842 * GDB's version number moved to ``version.in''
4844 The Makefile variable VERSION has been replaced by the file
4845 ``version.in''. People creating GDB distributions should update the
4846 contents of this file.
4850 GUD support is now a standard part of the EMACS distribution.
4852 *** Changes in GDB 5.0:
4854 * Improved support for debugging FP programs on x86 targets
4856 Unified and much-improved support for debugging floating-point
4857 programs on all x86 targets. In particular, ``info float'' now
4858 displays the FP registers in the same format on all x86 targets, with
4859 greater level of detail.
4861 * Improvements and bugfixes in hardware-assisted watchpoints
4863 It is now possible to watch array elements, struct members, and
4864 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4865 on x86 targets no longer erroneously trigger when the address is
4868 * Improvements in the native DJGPP version of GDB
4870 The distribution now includes all the scripts and auxiliary files
4871 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4872 machines ``out of the box''.
4874 The DJGPP version can now debug programs that use signals. It is
4875 possible to catch signals that happened in the debuggee, deliver
4876 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4877 would kill the program being debugged.) Programs that hook hardware
4878 interrupts (keyboard, timer, etc.) can also be debugged.
4880 It is now possible to debug DJGPP programs that redirect their
4881 standard handles or switch them to raw (as opposed to cooked) mode, or
4882 even close them. The command ``run < foo > bar'' works as expected,
4883 and ``info terminal'' reports useful information about the debuggee's
4884 terminal, including raw/cooked mode, redirection, etc.
4886 The DJGPP version now uses termios functions for console I/O, which
4887 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4890 DOS-style file names with drive letters are now fully supported by
4893 It is now possible to debug DJGPP programs that switch their working
4894 directory. It is also possible to rerun the debuggee any number of
4895 times without restarting GDB; thus, you can use the same setup,
4896 breakpoints, etc. for many debugging sessions.
4898 * New native configurations
4900 ARM GNU/Linux arm*-*-linux*
4901 PowerPC GNU/Linux powerpc-*-linux*
4905 Motorola MCore mcore-*-*
4906 x86 VxWorks i[3456]86-*-vxworks*
4907 PowerPC VxWorks powerpc-*-vxworks*
4908 TI TMS320C80 tic80-*-*
4910 * OBSOLETE configurations
4912 Altos 3068 m68*-altos-*
4913 Convex c1-*-*, c2-*-*
4915 ARM RISCix arm-*-* (as host)
4918 Configurations that have been declared obsolete will be commented out,
4919 but the code will be left in place. If there is no activity to revive
4920 these configurations before the next release of GDB, the sources will
4921 be permanently REMOVED.
4923 * Gould support removed
4925 Support for the Gould PowerNode and NP1 has been removed.
4927 * New features for SVR4
4929 On SVR4 native platforms (such as Solaris), if you attach to a process
4930 without first loading a symbol file, GDB will now attempt to locate and
4931 load symbols from the running process's executable file.
4933 * Many C++ enhancements
4935 C++ support has been greatly improved. Overload resolution now works properly
4936 in almost all cases. RTTI support is on the way.
4938 * Remote targets can connect to a sub-program
4940 A popen(3) style serial-device has been added. This device starts a
4941 sub-process (such as a stand-alone simulator) and then communicates
4942 with that. The sub-program to run is specified using the syntax
4943 ``|<program> <args>'' vis:
4945 (gdb) set remotedebug 1
4946 (gdb) target extended-remote |mn10300-elf-sim program-args
4948 * MIPS 64 remote protocol
4950 A long standing bug in the mips64 remote protocol where by GDB
4951 expected certain 32 bit registers (ex SR) to be transfered as 32
4952 instead of 64 bits has been fixed.
4954 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4955 added to provide backward compatibility with older versions of GDB.
4957 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4959 The command ``set remotebinarydownload'' command has been replaced by
4960 ``set remote X-packet''. Other commands in ``set remote'' family
4961 include ``set remote P-packet''.
4963 * Breakpoint commands accept ranges.
4965 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4966 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4967 ``tracepoint passcount'' also accepts a range of tracepoints.
4969 * ``apropos'' command added.
4971 The ``apropos'' command searches through command names and
4972 documentation strings, printing out matches, making it much easier to
4973 try to find a command that does what you are looking for.
4977 A new machine oriented interface (MI) has been added to GDB. This
4978 interface is designed for debug environments running GDB as a separate
4979 process. This is part of the long term libGDB project. See the
4980 "GDB/MI" chapter of the GDB manual for further information. It can be
4981 enabled by configuring with:
4983 .../configure --enable-gdbmi
4985 *** Changes in GDB-4.18:
4987 * New native configurations
4989 HP-UX 10.20 hppa*-*-hpux10.20
4990 HP-UX 11.x hppa*-*-hpux11.0*
4991 M68K GNU/Linux m68*-*-linux*
4995 Fujitsu FR30 fr30-*-elf*
4996 Intel StrongARM strongarm-*-*
4997 Mitsubishi D30V d30v-*-*
4999 * OBSOLETE configurations
5001 Gould PowerNode, NP1 np1-*-*, pn-*-*
5003 Configurations that have been declared obsolete will be commented out,
5004 but the code will be left in place. If there is no activity to revive
5005 these configurations before the next release of GDB, the sources will
5006 be permanently REMOVED.
5010 As a compatibility experiment, GDB's source files buildsym.h and
5011 buildsym.c have been converted to pure standard C, no longer
5012 containing any K&R compatibility code. We believe that all systems in
5013 use today either come with a standard C compiler, or have a GCC port
5014 available. If this is not true, please report the affected
5015 configuration to bug-gdb@gnu.org immediately. See the README file for
5016 information about getting a standard C compiler if you don't have one
5021 GDB now uses readline 2.2.
5023 * set extension-language
5025 You can now control the mapping between filename extensions and source
5026 languages by using the `set extension-language' command. For instance,
5027 you can ask GDB to treat .c files as C++ by saying
5028 set extension-language .c c++
5029 The command `info extensions' lists all of the recognized extensions
5030 and their associated languages.
5032 * Setting processor type for PowerPC and RS/6000
5034 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5035 you can use the `set processor' command to specify what variant of the
5036 PowerPC family you are debugging. The command
5040 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5041 following PowerPC and RS6000 variants:
5043 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5044 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5046 403GC IBM PowerPC 403GC
5047 505 Motorola PowerPC 505
5048 860 Motorola PowerPC 860 or 850
5049 601 Motorola PowerPC 601
5050 602 Motorola PowerPC 602
5051 603 Motorola/IBM PowerPC 603 or 603e
5052 604 Motorola PowerPC 604 or 604e
5053 750 Motorola/IBM PowerPC 750 or 750
5055 At the moment, this command just tells GDB what to name the
5056 special-purpose processor registers. Since almost all the affected
5057 registers are inaccessible to user-level programs, this command is
5058 only useful for remote debugging in its present form.
5062 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5063 more extensive support for HP-UX. Added features include shared
5064 library support, kernel threads and hardware watchpoints for 11.00,
5065 support for HP's ANSI C and C++ compilers, and a compatibility mode
5066 for xdb and dbx commands.
5070 HP's donation includes the new concept of catchpoints, which is a
5071 generalization of the old catch command. On HP-UX, it is now possible
5072 to catch exec, fork, and vfork, as well as library loading.
5074 This means that the existing catch command has changed; its first
5075 argument now specifies the type of catch to be set up. See the
5076 output of "help catch" for a list of catchpoint types.
5078 * Debugging across forks
5080 On HP-UX, you can choose which process to debug when a fork() happens
5085 HP has donated a curses-based terminal user interface (TUI). To get
5086 it, build with --enable-tui. Although this can be enabled for any
5087 configuration, at present it only works for native HP debugging.
5089 * GDB remote protocol additions
5091 A new protocol packet 'X' that writes binary data is now available.
5092 Default behavior is to try 'X', then drop back to 'M' if the stub
5093 fails to respond. The settable variable `remotebinarydownload'
5094 allows explicit control over the use of 'X'.
5096 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5097 full 64-bit address. The command
5099 set remoteaddresssize 32
5101 can be used to revert to the old behaviour. For existing remote stubs
5102 the change should not be noticed, as the additional address information
5105 In order to assist in debugging stubs, you may use the maintenance
5106 command `packet' to send any text string to the stub. For instance,
5108 maint packet heythere
5110 sends the packet "$heythere#<checksum>". Note that it is very easy to
5111 disrupt a debugging session by sending the wrong packet at the wrong
5114 The compare-sections command allows you to compare section data on the
5115 target to what is in the executable file without uploading or
5116 downloading, by comparing CRC checksums.
5118 * Tracing can collect general expressions
5120 You may now collect general expressions at tracepoints. This requires
5121 further additions to the target-side stub; see tracepoint.c and
5122 doc/agentexpr.texi for further details.
5124 * mask-address variable for Mips
5126 For Mips targets, you may control the zeroing of the upper 32 bits of
5127 a 64-bit address by entering `set mask-address on'. This is mainly
5128 of interest to users of embedded R4xxx and R5xxx processors.
5130 * Higher serial baud rates
5132 GDB's serial code now allows you to specify baud rates 57600, 115200,
5133 230400, and 460800 baud. (Note that your host system may not be able
5134 to achieve all of these rates.)
5138 The i960 configuration now includes an initial implementation of a
5139 builtin simulator, contributed by Jim Wilson.
5142 *** Changes in GDB-4.17:
5144 * New native configurations
5146 Alpha GNU/Linux alpha*-*-linux*
5147 Unixware 2.x i[3456]86-unixware2*
5148 Irix 6.x mips*-sgi-irix6*
5149 PowerPC GNU/Linux powerpc-*-linux*
5150 PowerPC Solaris powerpcle-*-solaris*
5151 Sparc GNU/Linux sparc-*-linux*
5152 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5156 Argonaut Risc Chip (ARC) arc-*-*
5157 Hitachi H8/300S h8300*-*-*
5158 Matsushita MN10200 w/simulator mn10200-*-*
5159 Matsushita MN10300 w/simulator mn10300-*-*
5160 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5161 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5162 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5163 Mitsubishi D10V w/simulator d10v-*-*
5164 Mitsubishi M32R/D w/simulator m32r-*-elf*
5165 Tsqware Sparclet sparclet-*-*
5166 NEC V850 w/simulator v850-*-*
5168 * New debugging protocols
5170 ARM with RDI protocol arm*-*-*
5171 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5172 DDB and LSI variants of PMON protocol mips*-*-*
5173 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5174 PowerPC with SDS protocol powerpc{,le}-*-eabi
5175 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5179 All configurations can now understand and use the DWARF 2 debugging
5180 format. The choice is automatic, if the symbol file contains DWARF 2
5185 GDB now includes basic Java language support. This support is
5186 only useful with Java compilers that produce native machine code.
5188 * solib-absolute-prefix and solib-search-path
5190 For SunOS and SVR4 shared libraries, you may now set the prefix for
5191 loading absolute shared library symbol files, and the search path for
5192 locating non-absolute shared library symbol files.
5194 * Live range splitting
5196 GDB can now effectively debug code for which GCC has performed live
5197 range splitting as part of its optimization. See gdb/doc/LRS for
5198 more details on the expected format of the stabs information.
5202 GDB's support for the GNU Hurd, including thread debugging, has been
5203 updated to work with current versions of the Hurd.
5207 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5208 instruction set. ARM GDB automatically detects when Thumb
5209 instructions are in use, and adjusts disassembly and backtracing
5214 GDB's MIPS target configurations now handle the MIP16 16-bit
5219 GDB now includes support for overlays; if an executable has been
5220 linked such that multiple sections are based at the same address, GDB
5221 will decide which section to use for symbolic info. You can choose to
5222 control the decision manually, using overlay commands, or implement
5223 additional target-side support and use "overlay load-target" to bring
5224 in the overlay mapping. Do "help overlay" for more detail.
5228 The command "info symbol <address>" displays information about
5229 the symbol at the specified address.
5233 The standard remote protocol now includes an extension that allows
5234 asynchronous collection and display of trace data. This requires
5235 extensive support in the target-side debugging stub. Tracing mode
5236 includes a new interaction mode in GDB and new commands: see the
5237 file tracepoint.c for more details.
5241 Configurations for embedded MIPS now include a simulator contributed
5242 by Cygnus Solutions. The simulator supports the instruction sets
5243 of most MIPS variants.
5247 Sparc configurations may now include the ERC32 simulator contributed
5248 by the European Space Agency. The simulator is not built into
5249 Sparc targets by default; configure with --enable-sim to include it.
5253 For target configurations that may include multiple variants of a
5254 basic architecture (such as MIPS and SH), you may now set the
5255 architecture explicitly. "set arch" sets, "info arch" lists
5256 the possible architectures.
5258 *** Changes in GDB-4.16:
5260 * New native configurations
5262 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5263 M68K NetBSD m68k-*-netbsd*
5264 PowerPC AIX 4.x powerpc-*-aix*
5265 PowerPC MacOS powerpc-*-macos*
5266 PowerPC Windows NT powerpcle-*-cygwin32
5267 RS/6000 AIX 4.x rs6000-*-aix4*
5271 ARM with RDP protocol arm-*-*
5272 I960 with MON960 i960-*-coff
5273 MIPS VxWorks mips*-*-vxworks*
5274 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5275 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5277 Matra Sparclet sparclet-*-*
5281 The powerpc-eabi configuration now includes the PSIM simulator,
5282 contributed by Andrew Cagney, with assistance from Mike Meissner.
5283 PSIM is a very elaborate model of the PowerPC, including not only
5284 basic instruction set execution, but also details of execution unit
5285 performance and I/O hardware. See sim/ppc/README for more details.
5289 GDB now works with Solaris 2.5.
5291 * Windows 95/NT native
5293 GDB will now work as a native debugger on Windows 95 and Windows NT.
5294 To build it from source, you must use the "gnu-win32" environment,
5295 which uses a DLL to emulate enough of Unix to run the GNU tools.
5296 Further information, binaries, and sources are available at
5297 ftp.cygnus.com, under pub/gnu-win32.
5299 * dont-repeat command
5301 If a user-defined command includes the command `dont-repeat', then the
5302 command will not be repeated if the user just types return. This is
5303 useful if the command is time-consuming to run, so that accidental
5304 extra keystrokes don't run the same command many times.
5306 * Send break instead of ^C
5308 The standard remote protocol now includes an option to send a break
5309 rather than a ^C to the target in order to interrupt it. By default,
5310 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5312 * Remote protocol timeout
5314 The standard remote protocol includes a new variable `remotetimeout'
5315 that allows you to set the number of seconds before GDB gives up trying
5316 to read from the target. The default value is 2.
5318 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5320 By default GDB will automatically keep track of objects as they are
5321 loaded and unloaded by the dynamic linker. By using the command `set
5322 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5323 when shared library events occur, thus allowing you to set breakpoints
5324 in shared libraries which are explicitly loaded by the inferior.
5326 Note this feature does not work on hpux8. On hpux9 you must link
5327 /usr/lib/end.o into your program. This feature should work
5328 automatically on hpux10.
5330 * Irix 5.x hardware watchpoint support
5332 Irix 5 configurations now support the use of hardware watchpoints.
5334 * Mips protocol "SYN garbage limit"
5336 When debugging a Mips target using the `target mips' protocol, you
5337 may set the number of characters that GDB will ignore by setting
5338 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5339 every character. The default value is 1050.
5341 * Recording and replaying remote debug sessions
5343 If you set `remotelogfile' to the name of a file, gdb will write to it
5344 a recording of a remote debug session. This recording may then be
5345 replayed back to gdb using "gdbreplay". See gdbserver/README for
5346 details. This is useful when you have a problem with GDB while doing
5347 remote debugging; you can make a recording of the session and send it
5348 to someone else, who can then recreate the problem.
5350 * Speedups for remote debugging
5352 GDB includes speedups for downloading and stepping MIPS systems using
5353 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5354 and more efficient S-record downloading.
5356 * Memory use reductions and statistics collection
5358 GDB now uses less memory and reports statistics about memory usage.
5359 Try the `maint print statistics' command, for example.
5361 *** Changes in GDB-4.15:
5363 * Psymtabs for XCOFF
5365 The symbol reader for AIX GDB now uses partial symbol tables. This
5366 can greatly improve startup time, especially for large executables.
5368 * Remote targets use caching
5370 Remote targets now use a data cache to speed up communication with the
5371 remote side. The data cache could lead to incorrect results because
5372 it doesn't know about volatile variables, thus making it impossible to
5373 debug targets which use memory mapped I/O devices. `set remotecache
5374 off' turns the the data cache off.
5376 * Remote targets may have threads
5378 The standard remote protocol now includes support for multiple threads
5379 in the target system, using new protocol commands 'H' and 'T'. See
5380 gdb/remote.c for details.
5384 If GDB is configured with `--enable-netrom', then it will include
5385 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5386 acts as though it is a bank of ROM on the target board, but you can
5387 write into it over the network. GDB's support consists only of
5388 support for fast loading into the emulated ROM; to debug, you must use
5389 another protocol, such as standard remote protocol. The usual
5390 sequence is something like
5392 target nrom <netrom-hostname>
5394 target remote <netrom-hostname>:1235
5398 GDB now includes support for the Apple Macintosh, as a host only. It
5399 may be run as either an MPW tool or as a standalone application, and
5400 it can debug through the serial port. All the usual GDB commands are
5401 available, but to the target command, you must supply "serial" as the
5402 device type instead of "/dev/ttyXX". See mpw-README in the main
5403 directory for more information on how to build. The MPW configuration
5404 scripts */mpw-config.in support only a few targets, and only the
5405 mips-idt-ecoff target has been tested.
5409 GDB configuration now uses autoconf. This is not user-visible,
5410 but does simplify configuration and building.
5414 GDB now supports hpux10.
5416 *** Changes in GDB-4.14:
5418 * New native configurations
5420 x86 FreeBSD i[345]86-*-freebsd
5421 x86 NetBSD i[345]86-*-netbsd
5422 NS32k NetBSD ns32k-*-netbsd
5423 Sparc NetBSD sparc-*-netbsd
5427 A29K VxWorks a29k-*-vxworks
5428 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5429 CPU32 EST-300 emulator m68*-*-est*
5430 PowerPC ELF powerpc-*-elf
5433 * Alpha OSF/1 support for procfs
5435 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5436 possible to attach to running processes. As the mounting of the /proc
5437 filesystem is optional on the Alpha, GDB automatically determines
5438 the availability of /proc during startup. This can lead to problems
5439 if /proc is unmounted after GDB has been started.
5441 * Arguments to user-defined commands
5443 User commands may accept up to 10 arguments separated by whitespace.
5444 Arguments are accessed within the user command via $arg0..$arg9. A
5447 print $arg0 + $arg1 + $arg2
5449 To execute the command use:
5452 Defines the command "adder" which prints the sum of its three arguments.
5453 Note the arguments are text substitutions, so they may reference variables,
5454 use complex expressions, or even perform inferior function calls.
5456 * New `if' and `while' commands
5458 This makes it possible to write more sophisticated user-defined
5459 commands. Both commands take a single argument, which is the
5460 expression to evaluate, and must be followed by the commands to
5461 execute, one per line, if the expression is nonzero, the list being
5462 terminated by the word `end'. The `if' command list may include an
5463 `else' word, which causes the following commands to be executed only
5464 if the expression is zero.
5466 * Fortran source language mode
5468 GDB now includes partial support for Fortran 77. It will recognize
5469 Fortran programs and can evaluate a subset of Fortran expressions, but
5470 variables and functions may not be handled correctly. GDB will work
5471 with G77, but does not yet know much about symbols emitted by other
5474 * Better HPUX support
5476 Most debugging facilities now work on dynamic executables for HPPAs
5477 running hpux9 or later. You can attach to running dynamically linked
5478 processes, but by default the dynamic libraries will be read-only, so
5479 for instance you won't be able to put breakpoints in them. To change
5480 that behavior do the following before running the program:
5486 This will cause the libraries to be mapped private and read-write.
5487 To revert to the normal behavior, do this:
5493 You cannot set breakpoints or examine data in the library until after
5494 the library is loaded if the function/data symbols do not have
5497 GDB can now also read debug symbols produced by the HP C compiler on
5498 HPPAs (sorry, no C++, Fortran or 68k support).
5500 * Target byte order now dynamically selectable
5502 You can choose which byte order to use with a target system, via the
5503 commands "set endian big" and "set endian little", and you can see the
5504 current setting by using "show endian". You can also give the command
5505 "set endian auto", in which case GDB will use the byte order
5506 associated with the executable. Currently, only embedded MIPS
5507 configurations support dynamic selection of target byte order.
5509 * New DOS host serial code
5511 This version uses DPMI interrupts to handle buffered I/O, so you
5512 no longer need to run asynctsr when debugging boards connected to
5515 *** Changes in GDB-4.13:
5517 * New "complete" command
5519 This lists all the possible completions for the rest of the line, if it
5520 were to be given as a command itself. This is intended for use by emacs.
5522 * Trailing space optional in prompt
5524 "set prompt" no longer adds a space for you after the prompt you set. This
5525 allows you to set a prompt which ends in a space or one that does not.
5527 * Breakpoint hit counts
5529 "info break" now displays a count of the number of times the breakpoint
5530 has been hit. This is especially useful in conjunction with "ignore"; you
5531 can ignore a large number of breakpoint hits, look at the breakpoint info
5532 to see how many times the breakpoint was hit, then run again, ignoring one
5533 less than that number, and this will get you quickly to the last hit of
5536 * Ability to stop printing at NULL character
5538 "set print null-stop" will cause GDB to stop printing the characters of
5539 an array when the first NULL is encountered. This is useful when large
5540 arrays actually contain only short strings.
5542 * Shared library breakpoints
5544 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5545 breakpoints in shared libraries before the executable is run.
5547 * Hardware watchpoints
5549 There is a new hardware breakpoint for the watch command for sparclite
5550 targets. See gdb/sparclite/hw_breakpoint.note.
5552 Hardware watchpoints are also now supported under GNU/Linux.
5556 Annotations have been added. These are for use with graphical interfaces,
5557 and are still experimental. Currently only gdba.el uses these.
5559 * Improved Irix 5 support
5561 GDB now works properly with Irix 5.2.
5563 * Improved HPPA support
5565 GDB now works properly with the latest GCC and GAS.
5567 * New native configurations
5569 Sequent PTX4 i[34]86-sequent-ptx4
5570 HPPA running OSF/1 hppa*-*-osf*
5571 Atari TT running SVR4 m68*-*-sysv4*
5572 RS/6000 LynxOS rs6000-*-lynxos*
5576 OS/9000 i[34]86-*-os9k
5577 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5580 * Hitachi SH7000 and E7000-PC ICE support
5582 There is now support for communicating with the Hitachi E7000-PC ICE.
5583 This is available automatically when GDB is configured for the SH.
5587 As usual, a variety of small fixes and improvements, both generic
5588 and configuration-specific. See the ChangeLog for more detail.
5590 *** Changes in GDB-4.12:
5592 * Irix 5 is now supported
5596 GDB-4.12 on the HPPA has a number of changes which make it unable
5597 to debug the output from the currently released versions of GCC and
5598 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5599 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5600 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5603 *** Changes in GDB-4.11:
5605 * User visible changes:
5609 The "set remotedebug" option is now consistent between the mips remote
5610 target, remote targets using the gdb-specific protocol, UDI (AMD's
5611 debug protocol for the 29k) and the 88k bug monitor. It is now an
5612 integer specifying a debug level (normally 0 or 1, but 2 means more
5613 debugging info for the mips target).
5615 * DEC Alpha native support
5617 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5618 debug info, but GDB works fairly well with the DEC compiler and should
5619 work with a future GCC release. See the README file for a few
5620 Alpha-specific notes.
5622 * Preliminary thread implementation
5624 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5626 * LynxOS native and target support for 386
5628 This release has been hosted on LynxOS 2.2, and also can be configured
5629 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5632 * Improvements in C++ mangling/demangling.
5634 This release has much better g++ debugging, specifically in name
5635 mangling/demangling, virtual function calls, print virtual table,
5636 call methods, ...etc.
5638 *** Changes in GDB-4.10:
5640 * User visible changes:
5642 Remote debugging using the GDB-specific (`target remote') protocol now
5643 supports the `load' command. This is only useful if you have some
5644 other way of getting the stub to the target system, and you can put it
5645 somewhere in memory where it won't get clobbered by the download.
5647 Filename completion now works.
5649 When run under emacs mode, the "info line" command now causes the
5650 arrow to point to the line specified. Also, "info line" prints
5651 addresses in symbolic form (as well as hex).
5653 All vxworks based targets now support a user settable option, called
5654 vxworks-timeout. This option represents the number of seconds gdb
5655 should wait for responses to rpc's. You might want to use this if
5656 your vxworks target is, perhaps, a slow software simulator or happens
5657 to be on the far side of a thin network line.
5661 This release contains support for using a DEC alpha as a GDB host for
5662 cross debugging. Native alpha debugging is not supported yet.
5665 *** Changes in GDB-4.9:
5669 This is the first GDB release which is accompanied by a matching testsuite.
5670 The testsuite requires installation of dejagnu, which should be available
5671 via ftp from most sites that carry GNU software.
5675 'Cfront' style demangling has had its name changed to 'ARM' style, to
5676 emphasize that it was written from the specifications in the C++ Annotated
5677 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5678 disclaimers, it still generated too much confusion with users attempting to
5679 use gdb with AT&T cfront.
5683 GDB now uses a standard remote interface to a simulator library.
5684 So far, the library contains simulators for the Zilog Z8001/2, the
5685 Hitachi H8/300, H8/500 and Super-H.
5687 * New targets supported
5689 H8/300 simulator h8300-hitachi-hms or h8300hms
5690 H8/500 simulator h8500-hitachi-hms or h8500hms
5691 SH simulator sh-hitachi-hms or sh
5692 Z8000 simulator z8k-zilog-none or z8ksim
5693 IDT MIPS board over serial line mips-idt-ecoff
5695 Cross-debugging to GO32 targets is supported. It requires a custom
5696 version of the i386-stub.c module which is integrated with the
5697 GO32 memory extender.
5699 * New remote protocols
5701 MIPS remote debugging protocol.
5703 * New source languages supported
5705 This version includes preliminary support for Chill, a Pascal like language
5706 used by telecommunications companies. Chill support is also being integrated
5707 into the GNU compiler, but we don't know when it will be publically available.
5710 *** Changes in GDB-4.8:
5712 * HP Precision Architecture supported
5714 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5715 version of this support was available as a set of patches from the
5716 University of Utah. GDB does not support debugging of programs
5717 compiled with the HP compiler, because HP will not document their file
5718 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5719 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5721 Many problems in the preliminary version have been fixed.
5723 * Faster and better demangling
5725 We have improved template demangling and fixed numerous bugs in the GNU style
5726 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5727 character types (wchar_t) are now supported. Demangling of each symbol is now
5728 only done once, and is cached when the symbol table for a file is read in.
5729 This results in a small increase in memory usage for C programs, a moderate
5730 increase in memory usage for C++ programs, and a fantastic speedup in
5733 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5734 from the specifications in the Annotated Reference Manual, which AT&T's
5735 compiler does not actually implement.
5737 * G++ multiple inheritance compiler problem
5739 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5740 inheritance lattices was reworked to properly discover ambiguities. We
5741 recently found an example which causes this new algorithm to fail in a
5742 very subtle way, producing bad debug information for those classes.
5743 The file 'gcc.patch' (in this directory) can be applied to gcc to
5744 circumvent the problem. A future GCC release will contain a complete
5747 The previous G++ debug info problem (mentioned below for the gdb-4.7
5748 release) is fixed in gcc version 2.3.2.
5750 * Improved configure script
5752 The `configure' script will now attempt to guess your system type if
5753 you don't supply a host system type. The old scheme of supplying a
5754 host system triplet is preferable over using this. All the magic is
5755 done in the new `config.guess' script. Examine it for details.
5757 We have also brought our configure script much more in line with the FSF's
5758 version. It now supports the --with-xxx options. In particular,
5759 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5760 The resulting GDB will not be able to read arbitrary object file formats --
5761 only the format ``expected'' to be used on the configured target system.
5762 We hope to make this the default in a future release.
5764 * Documentation improvements
5766 There's new internal documentation on how to modify GDB, and how to
5767 produce clean changes to the code. We implore people to read it
5768 before submitting changes.
5770 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5771 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5772 `info' files are also provided. To build `info' files from scratch,
5773 you will need the latest `makeinfo' release, which will be available in
5774 a future texinfo-X.Y release.
5776 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5777 We're not sure exactly which versions have this problem, but it has
5778 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5779 or better. If that isn't possible, there is a patch in
5780 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5781 around this problem.
5785 GDB now supports array constants that can be used in expressions typed in by
5786 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5787 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5790 The new directory `gdb/sparclite' contains a program that demonstrates
5791 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5793 * New native hosts supported
5795 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5796 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5798 * New targets supported
5800 AMD 29k family via UDI a29k-amd-udi or udi29k
5802 * New file formats supported
5804 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5805 HPUX core files, and SCO 3.2v2 core files.
5809 Attaching to processes now works again; thanks for the many bug reports.
5811 We have also stomped on a bunch of core dumps caused by
5812 printf_filtered("%s") problems.
5814 We eliminated a copyright problem on the rpc and ptrace header files
5815 for VxWorks, which was discovered at the last minute during the 4.7
5816 release. You should now be able to build a VxWorks GDB.
5818 You can now interrupt gdb while an attached process is running. This
5819 will cause the attached process to stop, and give control back to GDB.
5821 We fixed problems caused by using too many file descriptors
5822 for reading symbols from object files and libraries. This was
5823 especially a problem for programs that used many (~100) shared
5826 The `step' command now only enters a subroutine if there is line number
5827 information for the subroutine. Otherwise it acts like the `next'
5828 command. Previously, `step' would enter subroutines if there was
5829 any debugging information about the routine. This avoids problems
5830 when using `cc -g1' on MIPS machines.
5832 * Internal improvements
5834 GDB's internal interfaces have been improved to make it easier to support
5835 debugging of multiple languages in the future.
5837 GDB now uses a common structure for symbol information internally.
5838 Minimal symbols (derived from linkage symbols in object files), partial
5839 symbols (from a quick scan of debug information), and full symbols
5840 contain a common subset of information, making it easier to write
5841 shared code that handles any of them.
5843 * New command line options
5845 We now accept --silent as an alias for --quiet.
5849 The memory-mapped-malloc library is now licensed under the GNU Library
5850 General Public License.
5852 *** Changes in GDB-4.7:
5854 * Host/native/target split
5856 GDB has had some major internal surgery to untangle the support for
5857 hosts and remote targets. Now, when you configure GDB for a remote
5858 target, it will no longer load in all of the support for debugging
5859 local programs on the host. When fully completed and tested, this will
5860 ensure that arbitrary host/target combinations are possible.
5862 The primary conceptual shift is to separate the non-portable code in
5863 GDB into three categories. Host specific code is required any time GDB
5864 is compiled on that host, regardless of the target. Target specific
5865 code relates to the peculiarities of the target, but can be compiled on
5866 any host. Native specific code is everything else: it can only be
5867 built when the host and target are the same system. Child process
5868 handling and core file support are two common `native' examples.
5870 GDB's use of /proc for controlling Unix child processes is now cleaner.
5871 It has been split out into a single module under the `target_ops' vector,
5872 plus two native-dependent functions for each system that uses /proc.
5874 * New hosts supported
5876 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5877 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5878 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5880 * New targets supported
5882 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5883 68030 and CPU32 m68030-*-*, m68332-*-*
5885 * New native hosts supported
5887 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5888 (386bsd is not well tested yet)
5889 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5891 * New file formats supported
5893 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5894 supports reading of `a.out.adobe' object files, which are an a.out
5895 format extended with minimal information about multiple sections.
5899 `show copying' is the same as the old `info copying'.
5900 `show warranty' is the same as `info warrantee'.
5901 These were renamed for consistency. The old commands continue to work.
5903 `info handle' is a new alias for `info signals'.
5905 You can now define pre-command hooks, which attach arbitrary command
5906 scripts to any command. The commands in the hook will be executed
5907 prior to the user's command. You can also create a hook which will be
5908 executed whenever the program stops. See gdb.texinfo.
5912 We now deal with Cfront style name mangling, and can even extract type
5913 info from mangled symbols. GDB can automatically figure out which
5914 symbol mangling style your C++ compiler uses.
5916 Calling of methods and virtual functions has been improved as well.
5920 The crash that occured when debugging Sun Ansi-C compiled binaries is
5921 fixed. This was due to mishandling of the extra N_SO stabs output
5924 We also finally got Ultrix 4.2 running in house, and fixed core file
5925 support, with help from a dozen people on the net.
5927 John M. Farrell discovered that the reason that single-stepping was so
5928 slow on all of the Mips based platforms (primarily SGI and DEC) was
5929 that we were trying to demangle and lookup a symbol used for internal
5930 purposes on every instruction that was being stepped through. Changing
5931 the name of that symbol so that it couldn't be mistaken for a C++
5932 mangled symbol sped things up a great deal.
5934 Rich Pixley sped up symbol lookups in general by getting much smarter
5935 about when C++ symbol mangling is necessary. This should make symbol
5936 completion (TAB on the command line) much faster. It's not as fast as
5937 we'd like, but it's significantly faster than gdb-4.6.
5941 A new user controllable variable 'call_scratch_address' can
5942 specify the location of a scratch area to be used when GDB
5943 calls a function in the target. This is necessary because the
5944 usual method of putting the scratch area on the stack does not work
5945 in systems that have separate instruction and data spaces.
5947 We integrated changes to support the 29k UDI (Universal Debugger
5948 Interface), but discovered at the last minute that we didn't have all
5949 of the appropriate copyright paperwork. We are working with AMD to
5950 resolve this, and hope to have it available soon.
5954 We have sped up the remote serial line protocol, especially for targets
5955 with lots of registers. It now supports a new `expedited status' ('T')
5956 message which can be used in place of the existing 'S' status message.
5957 This allows the remote stub to send only the registers that GDB
5958 needs to make a quick decision about single-stepping or conditional
5959 breakpoints, eliminating the need to fetch the entire register set for
5960 each instruction being stepped through.
5962 The GDB remote serial protocol now implements a write-through cache for
5963 registers, only re-reading the registers if the target has run.
5965 There is also a new remote serial stub for SPARC processors. You can
5966 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5967 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5968 processor with a serial port.
5972 Configure.in files have become much easier to read and modify. A new
5973 `table driven' format makes it more obvious what configurations are
5974 supported, and what files each one uses.
5978 There is a new opcodes library which will eventually contain all of the
5979 disassembly routines and opcode tables. At present, it only contains
5980 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5981 disassembler (binutils/objdump) to share these routines.
5983 The libiberty library is now copylefted under the GNU Library General
5984 Public License. This allows more liberal use, and was done so libg++
5985 can use it. This makes no difference to GDB, since the Library License
5986 grants all the rights from the General Public License.
5990 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5991 reference to the stabs symbol info used by the debugger. It is (as far
5992 as we know) the only published document on this fascinating topic. We
5993 encourage you to read it, compare it to the stabs information on your
5994 system, and send improvements on the document in general (to
5995 bug-gdb@prep.ai.mit.edu).
5997 And, of course, many bugs have been fixed.
6000 *** Changes in GDB-4.6:
6002 * Better support for C++ function names
6004 GDB now accepts as input the "demangled form" of C++ overloaded function
6005 names and member function names, and can do command completion on such names
6006 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6007 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6008 Make use of command completion, it is your friend.
6010 GDB also now accepts a variety of C++ mangled symbol formats. They are
6011 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6012 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6013 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6014 for the list of formats.
6016 * G++ symbol mangling problem
6018 Recent versions of gcc have a bug in how they emit debugging information for
6019 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6020 directory) can be applied to gcc to fix the problem. Alternatively, if you
6021 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6022 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6023 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6026 * New 'maintenance' command
6028 All of the commands related to hacking GDB internals have been moved out of
6029 the main command set, and now live behind the 'maintenance' command. This
6030 can also be abbreviated as 'mt'. The following changes were made:
6032 dump-me -> maintenance dump-me
6033 info all-breakpoints -> maintenance info breakpoints
6034 printmsyms -> maintenance print msyms
6035 printobjfiles -> maintenance print objfiles
6036 printpsyms -> maintenance print psymbols
6037 printsyms -> maintenance print symbols
6039 The following commands are new:
6041 maintenance demangle Call internal GDB demangler routine to
6042 demangle a C++ link name and prints the result.
6043 maintenance print type Print a type chain for a given symbol
6045 * Change to .gdbinit file processing
6047 We now read the $HOME/.gdbinit file before processing the argv arguments
6048 (e.g. reading symbol files or core files). This allows global parameters to
6049 be set, which will apply during the symbol reading. The ./.gdbinit is still
6050 read after argv processing.
6052 * New hosts supported
6054 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6056 GNU/Linux support i386-unknown-linux or linux
6058 We are also including code to support the HP/PA running BSD and HPUX. This
6059 is almost guaranteed not to work, as we didn't have time to test or build it
6060 for this release. We are including it so that the more adventurous (or
6061 masochistic) of you can play with it. We also had major problems with the
6062 fact that the compiler that we got from HP doesn't support the -g option.
6065 * New targets supported
6067 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6069 * More smarts about finding #include files
6071 GDB now remembers the compilation directory for all include files, and for
6072 all files from which C is generated (like yacc and lex sources). This
6073 greatly improves GDB's ability to find yacc/lex sources, and include files,
6074 especially if you are debugging your program from a directory different from
6075 the one that contains your sources.
6077 We also fixed a bug which caused difficulty with listing and setting
6078 breakpoints in include files which contain C code. (In the past, you had to
6079 try twice in order to list an include file that you hadn't looked at before.)
6081 * Interesting infernals change
6083 GDB now deals with arbitrary numbers of sections, where the symbols for each
6084 section must be relocated relative to that section's landing place in the
6085 target's address space. This work was needed to support ELF with embedded
6086 stabs used by Solaris-2.0.
6088 * Bug fixes (of course!)
6090 There have been loads of fixes for the following things:
6091 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6092 i960, stabs, DOS(GO32), procfs, etc...
6094 See the ChangeLog for details.
6096 *** Changes in GDB-4.5:
6098 * New machines supported (host and target)
6100 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6102 SGI Irix-4.x mips-sgi-irix4 or iris4
6104 * New malloc package
6106 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6107 Mmalloc is capable of handling mutiple heaps of memory. It is also
6108 capable of saving a heap to a file, and then mapping it back in later.
6109 This can be used to greatly speedup the startup of GDB by using a
6110 pre-parsed symbol table which lives in a mmalloc managed heap. For
6111 more details, please read mmalloc/mmalloc.texi.
6115 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6116 'help info proc' for details.
6118 * MIPS ecoff symbol table format
6120 The code that reads MIPS symbol table format is now supported on all hosts.
6121 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6124 * File name changes for MS-DOS
6126 Many files in the config directories have been renamed to make it easier to
6127 support GDB on MS-DOSe systems (which have very restrictive file name
6128 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6129 environment) is close to working but has some remaining problems. Note
6130 that debugging of DOS programs is not supported, due to limitations
6131 in the ``operating system'', but it can be used to host cross-debugging.
6133 * Cross byte order fixes
6135 Many fixes have been made to support cross debugging of Sparc and MIPS
6136 targets from hosts whose byte order differs.
6138 * New -mapped and -readnow options
6140 If memory-mapped files are available on your system through the 'mmap'
6141 system call, you can use the -mapped option on the `file' or
6142 `symbol-file' commands to cause GDB to write the symbols from your
6143 program into a reusable file. If the program you are debugging is
6144 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6145 Future GDB debugging sessions will notice the presence of this file,
6146 and will quickly map in symbol information from it, rather than reading
6147 the symbol table from the executable program. Using the '-mapped'
6148 option in a GDB `file' or `symbol-file' command has the same effect as
6149 starting GDB with the '-mapped' command-line option.
6151 You can cause GDB to read the entire symbol table immediately by using
6152 the '-readnow' option with any of the commands that load symbol table
6153 information (or on the GDB command line). This makes the command
6154 slower, but makes future operations faster.
6156 The -mapped and -readnow options are typically combined in order to
6157 build a `fred.syms' file that contains complete symbol information.
6158 A simple GDB invocation to do nothing but build a `.syms' file for future
6161 gdb -batch -nx -mapped -readnow programname
6163 The `.syms' file is specific to the host machine on which GDB is run.
6164 It holds an exact image of GDB's internal symbol table. It cannot be
6165 shared across multiple host platforms.
6167 * longjmp() handling
6169 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6170 siglongjmp() without losing control. This feature has not yet been ported to
6171 all systems. It currently works on many 386 platforms, all MIPS-based
6172 platforms (SGI, DECstation, etc), and Sun3/4.
6176 Preliminary work has been put in to support the new Solaris OS from Sun. At
6177 this time, it can control and debug processes, but it is not capable of
6182 As always, many many bug fixes. The major areas were with g++, and mipsread.
6183 People using the MIPS-based platforms should experience fewer mysterious
6184 crashes and trashed symbol tables.
6186 *** Changes in GDB-4.4:
6188 * New machines supported (host and target)
6190 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6192 BSD Reno on Vax vax-dec-bsd
6193 Ultrix on Vax vax-dec-ultrix
6195 * New machines supported (target)
6197 AMD 29000 embedded, using EBMON a29k-none-none
6201 GDB continues to improve its handling of C++. `References' work better.
6202 The demangler has also been improved, and now deals with symbols mangled as
6203 per the Annotated C++ Reference Guide.
6205 GDB also now handles `stabs' symbol information embedded in MIPS
6206 `ecoff' symbol tables. Since the ecoff format was not easily
6207 extensible to handle new languages such as C++, this appeared to be a
6208 good way to put C++ debugging info into MIPS binaries. This option
6209 will be supported in the GNU C compiler, version 2, when it is
6212 * New features for SVR4
6214 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6215 shared libraries. Debugging dynamically linked programs should present
6216 only minor differences from debugging statically linked programs.
6218 The `info proc' command will print out information about any process
6219 on an SVR4 system (including the one you are debugging). At the moment,
6220 it prints the address mappings of the process.
6222 If you bring up GDB on another SVR4 system, please send mail to
6223 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6225 * Better dynamic linking support in SunOS
6227 Reading symbols from shared libraries which contain debugging symbols
6228 now works properly. However, there remain issues such as automatic
6229 skipping of `transfer vector' code during function calls, which
6230 make it harder to debug code in a shared library, than to debug the
6231 same code linked statically.
6235 GDB is now using the latest `getopt' routines from the FSF. This
6236 version accepts the -- prefix for options with long names. GDB will
6237 continue to accept the old forms (-option and +option) as well.
6238 Various single letter abbreviations for options have been explicity
6239 added to the option table so that they won't get overshadowed in the
6240 future by other options that begin with the same letter.
6244 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6245 Many assorted bugs have been handled. Many more remain to be handled.
6246 See the various ChangeLog files (primarily in gdb and bfd) for details.
6249 *** Changes in GDB-4.3:
6251 * New machines supported (host and target)
6253 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6254 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6255 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6257 * Almost SCO Unix support
6259 We had hoped to support:
6260 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6261 (except for core file support), but we discovered very late in the release
6262 that it has problems with process groups that render gdb unusable. Sorry
6263 about that. I encourage people to fix it and post the fixes.
6265 * Preliminary ELF and DWARF support
6267 GDB can read ELF object files on System V Release 4, and can handle
6268 debugging records for C, in DWARF format, in ELF files. This support
6269 is preliminary. If you bring up GDB on another SVR4 system, please
6270 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6275 GDB now uses the latest `readline' library. One user-visible change
6276 is that two tabs will list possible command completions, which previously
6277 required typing M-? (meta-question mark, or ESC ?).
6281 The `stepi' bug that many of you noticed has been squashed.
6282 Many bugs in C++ have been handled. Many more remain to be handled.
6283 See the various ChangeLog files (primarily in gdb and bfd) for details.
6285 * State of the MIPS world (in case you wondered):
6287 GDB can understand the symbol tables emitted by the compilers
6288 supplied by most vendors of MIPS-based machines, including DEC. These
6289 symbol tables are in a format that essentially nobody else uses.
6291 Some versions of gcc come with an assembler post-processor called
6292 mips-tfile. This program is required if you want to do source-level
6293 debugging of gcc-compiled programs. I believe FSF does not ship
6294 mips-tfile with gcc version 1, but it will eventually come with gcc
6297 Debugging of g++ output remains a problem. g++ version 1.xx does not
6298 really support it at all. (If you're lucky, you should be able to get
6299 line numbers and stack traces to work, but no parameters or local
6300 variables.) With some work it should be possible to improve the
6303 When gcc version 2 is released, you will have somewhat better luck.
6304 However, even then you will get confusing results for inheritance and
6307 We will eventually provide full debugging of g++ output on
6308 DECstations. This will probably involve some kind of stabs-in-ecoff
6309 encapulation, but the details have not been worked out yet.
6312 *** Changes in GDB-4.2:
6314 * Improved configuration
6316 Only one copy of `configure' exists now, and it is not self-modifying.
6317 Porting BFD is simpler.
6321 The `step' and `next' commands now only stop at the first instruction
6322 of a source line. This prevents the multiple stops that used to occur
6323 in switch statements, for-loops, etc. `Step' continues to stop if a
6324 function that has debugging information is called within the line.
6328 Lots of small bugs fixed. More remain.
6330 * New host supported (not target)
6332 Intel 386 PC clone running Mach i386-none-mach
6335 *** Changes in GDB-4.1:
6337 * Multiple source language support
6339 GDB now has internal scaffolding to handle several source languages.
6340 It determines the type of each source file from its filename extension,
6341 and will switch expression parsing and number formatting to match the
6342 language of the function in the currently selected stack frame.
6343 You can also specifically set the language to be used, with
6344 `set language c' or `set language modula-2'.
6348 GDB now has preliminary support for the GNU Modula-2 compiler,
6349 currently under development at the State University of New York at
6350 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6351 continue through the fall of 1991 and into 1992.
6353 Other Modula-2 compilers are currently not supported, and attempting to
6354 debug programs compiled with them will likely result in an error as the
6355 symbol table is read. Feel free to work on it, though!
6357 There are hooks in GDB for strict type checking and range checking,
6358 in the `Modula-2 philosophy', but they do not currently work.
6362 GDB can now write to executable and core files (e.g. patch
6363 a variable's value). You must turn this switch on, specify
6364 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6365 by assigning a new value to a variable. Modifications take
6368 * Automatic SunOS shared library reading
6370 When you run your program, GDB automatically determines where its
6371 shared libraries (if any) have been loaded, and reads their symbols.
6372 The `share' command is no longer needed. This also works when
6373 examining core files.
6377 You can specify the number of lines that the `list' command shows.
6380 * New machines supported (host and target)
6382 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6383 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6384 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6386 * New hosts supported (not targets)
6388 IBM RT/PC: romp-ibm-aix or rtpc
6390 * New targets supported (not hosts)
6392 AMD 29000 embedded with COFF a29k-none-coff
6393 AMD 29000 embedded with a.out a29k-none-aout
6394 Ultracomputer remote kernel debug a29k-nyu-kern
6396 * New remote interfaces
6402 *** Changes in GDB-4.0:
6406 Wide output is wrapped at good places to make the output more readable.
6408 Gdb now supports cross-debugging from a host machine of one type to a
6409 target machine of another type. Communication with the target system
6410 is over serial lines. The ``target'' command handles connecting to the
6411 remote system; the ``load'' command will download a program into the
6412 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6413 also supports debugging of realtime processes running under VxWorks,
6414 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6415 stub on the target system.
6417 New CPUs supported include the AMD 29000 and Intel 960.
6419 GDB now reads object files and symbol tables via a ``binary file''
6420 library, which allows a single copy of GDB to debug programs of multiple
6421 object file types such as a.out and coff.
6423 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6424 refcard.dvi and refcard.ps are available to format it).
6427 * Control-Variable user interface simplified
6429 All variables that control the operation of the debugger can be set
6430 by the ``set'' command, and displayed by the ``show'' command.
6432 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6433 ``Show prompt'' produces the response:
6434 Gdb's prompt is new-gdb=>.
6436 What follows are the NEW set commands. The command ``help set'' will
6437 print a complete list of old and new set commands. ``help set FOO''
6438 will give a longer description of the variable FOO. ``show'' will show
6439 all of the variable descriptions and their current settings.
6441 confirm on/off: Enables warning questions for operations that are
6442 hard to recover from, e.g. rerunning the program while
6443 it is already running. Default is ON.
6445 editing on/off: Enables EMACS style command line editing
6446 of input. Previous lines can be recalled with
6447 control-P, the current line can be edited with control-B,
6448 you can search for commands with control-R, etc.
6451 history filename NAME: NAME is where the gdb command history
6452 will be stored. The default is .gdb_history,
6453 or the value of the environment variable
6456 history size N: The size, in commands, of the command history. The
6457 default is 256, or the value of the environment variable
6460 history save on/off: If this value is set to ON, the history file will
6461 be saved after exiting gdb. If set to OFF, the
6462 file will not be saved. The default is OFF.
6464 history expansion on/off: If this value is set to ON, then csh-like
6465 history expansion will be performed on
6466 command line input. The default is OFF.
6468 radix N: Sets the default radix for input and output. It can be set
6469 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6470 in the current radix, so "set radix 10" is always a no-op.
6472 height N: This integer value is the number of lines on a page. Default
6473 is 24, the current `stty rows'' setting, or the ``li#''
6474 setting from the termcap entry matching the environment
6477 width N: This integer value is the number of characters on a line.
6478 Default is 80, the current `stty cols'' setting, or the ``co#''
6479 setting from the termcap entry matching the environment
6482 Note: ``set screensize'' is obsolete. Use ``set height'' and
6483 ``set width'' instead.
6485 print address on/off: Print memory addresses in various command displays,
6486 such as stack traces and structure values. Gdb looks
6487 more ``symbolic'' if you turn this off; it looks more
6488 ``machine level'' with it on. Default is ON.
6490 print array on/off: Prettyprint arrays. New convenient format! Default
6493 print demangle on/off: Print C++ symbols in "source" form if on,
6496 print asm-demangle on/off: Same, for assembler level printouts
6499 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6502 * Support for Epoch Environment.
6504 The epoch environment is a version of Emacs v18 with windowing. One
6505 new command, ``inspect'', is identical to ``print'', except that if you
6506 are running in the epoch environment, the value is printed in its own
6510 * Support for Shared Libraries
6512 GDB can now debug programs and core files that use SunOS shared libraries.
6513 Symbols from a shared library cannot be referenced
6514 before the shared library has been linked with the program (this
6515 happens after you type ``run'' and before the function main() is entered).
6516 At any time after this linking (including when examining core files
6517 from dynamically linked programs), gdb reads the symbols from each
6518 shared library when you type the ``sharedlibrary'' command.
6519 It can be abbreviated ``share''.
6521 sharedlibrary REGEXP: Load shared object library symbols for files
6522 matching a unix regular expression. No argument
6523 indicates to load symbols for all shared libraries.
6525 info sharedlibrary: Status of loaded shared libraries.
6530 A watchpoint stops execution of a program whenever the value of an
6531 expression changes. Checking for this slows down execution
6532 tremendously whenever you are in the scope of the expression, but is
6533 quite useful for catching tough ``bit-spreader'' or pointer misuse
6534 problems. Some machines such as the 386 have hardware for doing this
6535 more quickly, and future versions of gdb will use this hardware.
6537 watch EXP: Set a watchpoint (breakpoint) for an expression.
6539 info watchpoints: Information about your watchpoints.
6541 delete N: Deletes watchpoint number N (same as breakpoints).
6542 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6543 enable N: Re-enables watchpoint number N (same as breakpoints).
6546 * C++ multiple inheritance
6548 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6551 * C++ exception handling
6553 Gdb now supports limited C++ exception handling. Besides the existing
6554 ability to breakpoint on an exception handler, gdb can breakpoint on
6555 the raising of an exception (before the stack is peeled back to the
6558 catch FOO: If there is a FOO exception handler in the dynamic scope,
6559 set a breakpoint to catch exceptions which may be raised there.
6560 Multiple exceptions (``catch foo bar baz'') may be caught.
6562 info catch: Lists all exceptions which may be caught in the
6563 current stack frame.
6566 * Minor command changes
6568 The command ``call func (arg, arg, ...)'' now acts like the print
6569 command, except it does not print or save a value if the function's result
6570 is void. This is similar to dbx usage.
6572 The ``up'' and ``down'' commands now always print the frame they end up
6573 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6574 frames without printing.
6576 * New directory command
6578 'dir' now adds directories to the FRONT of the source search path.
6579 The path starts off empty. Source files that contain debug information
6580 about the directory in which they were compiled can be found even
6581 with an empty path; Sun CC and GCC include this information. If GDB can't
6582 find your source file in the current directory, type "dir .".
6584 * Configuring GDB for compilation
6586 For normal use, type ``./configure host''. See README or gdb.texinfo
6589 GDB now handles cross debugging. If you are remotely debugging between
6590 two different machines, type ``./configure host -target=targ''.
6591 Host is the machine where GDB will run; targ is the machine
6592 where the program that you are debugging will run.