1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.11
6 * GDB now supports a negative repeat count in the 'x' command to examine
7 memory backward from the given address. For example:
10 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
11 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
12 (gdb) x/-5i 0x0000000000400580
13 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
14 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
15 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
16 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
17 0x40057b <main(int, char**)+25>:
18 callq 0x400536 <Func1(int, char const*)>
20 * Fortran: Support structures with fields of dynamic types and
21 arrays of dynamic types.
23 * GDB now supports multibit bitfields and enums in target register
26 * New Python-based convenience function $_as_string(val), which returns
27 the textual representation of a value. This function is especially
28 useful to obtain the text label of an enum value.
30 * Intel MPX bound violation handling.
32 Segmentation faults caused by a Intel MPX boundary violation
33 now display the kind of violation (upper or lower), the memory
34 address accessed and the memory bounds, along with the usual
35 signal received and code location.
39 Program received signal SIGSEGV, Segmentation fault
40 Upper bound violation while accessing address 0x7fffffffc3b3
41 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
42 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
44 * Rust language support.
45 GDB now supports debugging programs written in the Rust programming
46 language. See https://www.rust-lang.org/ for more information about
49 * Support for running interpreters on specified input/output devices
51 GDB now supports a new mechanism that allows frontends to provide
52 fully featured GDB console views, as a better alternative to
53 building such views on top of the "-interpreter-exec console"
54 command. See the new "new-ui" command below. With that command,
55 frontends can now start GDB in the traditional command-line mode
56 running in an embedded terminal emulator widget, and create a
57 separate MI interpreter running on a specified i/o device. In this
58 way, GDB handles line editing, history, tab completion, etc. in the
59 console all by itself, and the GUI uses the separate MI interpreter
60 for its own control and synchronization, invisible to the command
63 * The "catch syscall" command catches groups of related syscalls.
65 The "catch syscall" command now supports catching a group of related
66 syscalls using the 'group:' or 'g:' prefix.
71 skip -gfile file-glob-pattern
72 skip -function function
73 skip -rfunction regular-expression
74 A generalized form of the skip command, with new support for
75 glob-style file names and regular expressions for function names.
76 Additionally, a file spec and a function spec may now be combined.
78 maint info line-table REGEXP
79 Display the contents of GDB's internal line table data struture.
82 Run any GDB unit tests that were compiled in.
85 Start a new user interface instance running INTERP as interpreter,
86 using the TTY file for input/output.
90 ** gdb.Breakpoint objects have a new attribute "pending", which
91 indicates whether the breakpoint is pending.
94 Signal ("set") the given MS-Windows event object. This is used in
95 conjunction with the Windows JIT debugging (AeDebug) support, where
96 the OS suspends a crashing process until a debugger can attach to
97 it. Resuming the crashing process, in order to debug it, is done by
100 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
101 was added in GDBserver, including JIT compiling fast tracepoint's
102 conditional expression bytecode into native code.
104 * Support for various remote target protocols and ROM monitors has
107 target m32rsdi Remote M32R debugging over SDI
108 target mips MIPS remote debugging protocol
109 target pmon PMON ROM monitor
110 target ddb NEC's DDB variant of PMON for Vr4300
111 target rockhopper NEC RockHopper variant of PMON
112 target lsi LSI variant of PMO
114 * Support for tracepoints and fast tracepoints on powerpc-linux,
115 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
116 including JIT compiling fast tracepoint's conditional expression
117 bytecode into native code.
119 * MI async record =record-started now includes the method and format used for
120 recording. For example:
122 =record-started,thread-group="i1",method="btrace",format="bts"
126 Andes NDS32 nds32*-*-elf
128 *** Changes in GDB 7.11
130 * GDB now supports debugging kernel-based threads on FreeBSD.
132 * Per-inferior thread numbers
134 Thread numbers are now per inferior instead of global. If you're
135 debugging multiple inferiors, GDB displays thread IDs using a
136 qualified INF_NUM.THR_NUM form. For example:
140 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
141 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
142 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
143 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
145 As consequence, thread numbers as visible in the $_thread
146 convenience variable and in Python's InferiorThread.num attribute
147 are no longer unique between inferiors.
149 GDB now maintains a second thread ID per thread, referred to as the
150 global thread ID, which is the new equivalent of thread numbers in
151 previous releases. See also $_gthread below.
153 For backwards compatibility, MI's thread IDs always refer to global
156 * Commands that accept thread IDs now accept the qualified
157 INF_NUM.THR_NUM form as well. For example:
160 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
163 * In commands that accept a list of thread IDs, you can now refer to
164 all threads of an inferior using a star wildcard. GDB accepts
165 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
166 refer to all threads of the current inferior. For example, "info
169 * You can use "info threads -gid" to display the global thread ID of
172 * The new convenience variable $_gthread holds the global number of
175 * The new convenience variable $_inferior holds the number of the
178 * GDB now displays the ID and name of the thread that hit a breakpoint
179 or received a signal, if your program is multi-threaded. For
182 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
183 Thread 1 "main" received signal SIGINT, Interrupt.
185 * Record btrace now supports non-stop mode.
187 * Support for tracepoints on aarch64-linux was added in GDBserver.
189 * The 'record instruction-history' command now indicates speculative execution
190 when using the Intel Processor Trace recording format.
192 * GDB now allows users to specify explicit locations, bypassing
193 the linespec parser. This feature is also available to GDB/MI
196 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
197 GDB now is able to debug both AArch64 applications and ARM applications
200 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
201 including JIT compiling fast tracepoint's conditional expression bytecode
204 * GDB now supports displaced stepping on AArch64 GNU/Linux.
206 * "info threads", "info inferiors", "info display", "info checkpoints"
207 and "maint info program-spaces" now list the corresponding items in
208 ascending ID order, for consistency with all other "info" commands.
210 * In Ada, the overloads selection menu has been enhanced to display the
211 parameter types and the return types for the matching overloaded subprograms.
215 maint set target-non-stop (on|off|auto)
216 maint show target-non-stop
217 Control whether GDB targets always operate in non-stop mode even if
218 "set non-stop" is "off". The default is "auto", meaning non-stop
219 mode is enabled if supported by the target.
221 maint set bfd-sharing
222 maint show bfd-sharing
223 Control the reuse of bfd objects.
227 Control display of debugging info regarding bfd caching.
231 Control display of debugging info regarding FreeBSD threads.
233 set remote multiprocess-extensions-packet
234 show remote multiprocess-extensions-packet
235 Set/show the use of the remote protocol multiprocess extensions.
237 set remote thread-events
238 show remote thread-events
239 Set/show the use of thread create/exit events.
241 set ada print-signatures on|off
242 show ada print-signatures"
243 Control whether parameter types and return types are displayed in overloads
244 selection menus. It is activaled (@code{on}) by default.
248 Controls the maximum size of memory, in bytes, that GDB will
249 allocate for value contents. Prevents incorrect programs from
250 causing GDB to allocate overly large buffers. Default is 64k.
252 * The "disassemble" command accepts a new modifier: /s.
253 It prints mixed source+disassembly like /m with two differences:
254 - disassembled instructions are now printed in program order, and
255 - and source for all relevant files is now printed.
256 The "/m" option is now considered deprecated: its "source-centric"
257 output hasn't proved useful in practice.
259 * The "record instruction-history" command accepts a new modifier: /s.
260 It behaves exactly like /m and prints mixed source+disassembly.
262 * The "set scheduler-locking" command supports a new mode "replay".
263 It behaves like "off" in record mode and like "on" in replay mode.
265 * Support for various ROM monitors has been removed:
267 target dbug dBUG ROM monitor for Motorola ColdFire
268 target picobug Motorola picobug monitor
269 target dink32 DINK32 ROM monitor for PowerPC
270 target m32r Renesas M32R/D ROM monitor
271 target mon2000 mon2000 ROM monitor
272 target ppcbug PPCBUG ROM monitor for PowerPC
274 * Support for reading/writing memory and extracting values on architectures
275 whose memory is addressable in units of any integral multiple of 8 bits.
280 Indicates that an exec system call was executed.
282 exec-events feature in qSupported
283 The qSupported packet allows GDB to request support for exec
284 events using the new 'gdbfeature' exec-event, and the qSupported
285 response can contain the corresponding 'stubfeature'. Set and
286 show commands can be used to display whether these features are enabled.
289 Equivalent to interrupting with the ^C character, but works in
292 thread created stop reason (T05 create:...)
293 Indicates that the thread was just created and is stopped at entry.
295 thread exit stop reply (w exitcode;tid)
296 Indicates that the thread has terminated.
299 Enables/disables thread create and exit event reporting. For
300 example, this is used in non-stop mode when GDB stops a set of
301 threads and synchronously waits for the their corresponding stop
302 replies. Without exit events, if one of the threads exits, GDB
303 would hang forever not knowing that it should no longer expect a
304 stop for that same thread.
307 Indicates that there are no resumed threads left in the target (all
308 threads are stopped). The remote stub reports support for this stop
309 reply to GDB's qSupported query.
312 Enables/disables catching syscalls from the inferior process.
313 The remote stub reports support for this packet to GDB's qSupported query.
315 syscall_entry stop reason
316 Indicates that a syscall was just called.
318 syscall_return stop reason
319 Indicates that a syscall just returned.
321 * Extended-remote exec events
323 ** GDB now has support for exec events on extended-remote Linux targets.
324 For such targets with Linux kernels 2.5.46 and later, this enables
325 follow-exec-mode and exec catchpoints.
327 set remote exec-event-feature-packet
328 show remote exec-event-feature-packet
329 Set/show the use of the remote exec event feature.
331 * Thread names in remote protocol
333 The reply to qXfer:threads:read may now include a name attribute for each
336 * Target remote mode fork and exec events
338 ** GDB now has support for fork and exec events on target remote mode
339 Linux targets. For such targets with Linux kernels 2.5.46 and later,
340 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
341 fork and exec catchpoints.
343 * Remote syscall events
345 ** GDB now has support for catch syscall on remote Linux targets,
346 currently enabled on x86/x86_64 architectures.
348 set remote catch-syscall-packet
349 show remote catch-syscall-packet
350 Set/show the use of the remote catch syscall feature.
354 ** The -var-set-format command now accepts the zero-hexadecimal
355 format. It outputs data in hexadecimal format with zero-padding on the
360 ** gdb.InferiorThread objects have a new attribute "global_num",
361 which refers to the thread's global thread ID. The existing
362 "num" attribute now refers to the thread's per-inferior number.
363 See "Per-inferior thread numbers" above.
364 ** gdb.InferiorThread objects have a new attribute "inferior", which
365 is the Inferior object the thread belongs to.
367 *** Changes in GDB 7.10
369 * Support for process record-replay and reverse debugging on aarch64*-linux*
370 targets has been added. GDB now supports recording of A64 instruction set
371 including advance SIMD instructions.
373 * Support for Sun's version of the "stabs" debug file format has been removed.
375 * GDB now honors the content of the file /proc/PID/coredump_filter
376 (PID is the process ID) on GNU/Linux systems. This file can be used
377 to specify the types of memory mappings that will be included in a
378 corefile. For more information, please refer to the manual page of
379 "core(5)". GDB also has a new command: "set use-coredump-filter
380 on|off". It allows to set whether GDB will read the content of the
381 /proc/PID/coredump_filter file when generating a corefile.
383 * The "info os" command on GNU/Linux can now display information on
385 "info os cpus" Listing of all cpus/cores on the system
387 * GDB has two new commands: "set serial parity odd|even|none" and
388 "show serial parity". These allows to set or show parity for the
391 * The "info source" command now displays the producer string if it was
392 present in the debug info. This typically includes the compiler version
393 and may include things like its command line arguments.
395 * The "info dll", an alias of the "info sharedlibrary" command,
396 is now available on all platforms.
398 * Directory names supplied to the "set sysroot" commands may be
399 prefixed with "target:" to tell GDB to access shared libraries from
400 the target system, be it local or remote. This replaces the prefix
401 "remote:". The default sysroot has been changed from "" to
402 "target:". "remote:" is automatically converted to "target:" for
403 backward compatibility.
405 * The system root specified by "set sysroot" will be prepended to the
406 filename of the main executable (if reported to GDB as absolute by
407 the operating system) when starting processes remotely, and when
408 attaching to already-running local or remote processes.
410 * GDB now supports automatic location and retrieval of executable
411 files from remote targets. Remote debugging can now be initiated
412 using only a "target remote" or "target extended-remote" command
413 (no "set sysroot" or "file" commands are required). See "New remote
416 * The "dump" command now supports verilog hex format.
418 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
420 * On GNU/Linux, GDB and gdbserver are now able to access executable
421 and shared library files without a "set sysroot" command when
422 attaching to processes running in different mount namespaces from
423 the debugger. This makes it possible to attach to processes in
424 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
425 See "New remote packets" below.
427 * The "tui reg" command now provides completion for all of the
428 available register groups, including target specific groups.
430 * The HISTSIZE environment variable is no longer read when determining
431 the size of GDB's command history. GDB now instead reads the dedicated
432 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
433 disables truncation of command history. Non-numeric values of GDBHISTSIZE
438 ** Memory ports can now be unbuffered.
442 ** gdb.Objfile objects have a new attribute "username",
443 which is the name of the objfile as specified by the user,
444 without, for example, resolving symlinks.
445 ** You can now write frame unwinders in Python.
446 ** gdb.Type objects have a new method "optimized_out",
447 returning optimized out gdb.Value instance of this type.
448 ** gdb.Value objects have new methods "reference_value" and
449 "const_value" which return a reference to the value and a
450 "const" version of the value respectively.
454 maint print symbol-cache
455 Print the contents of the symbol cache.
457 maint print symbol-cache-statistics
458 Print statistics of symbol cache usage.
460 maint flush-symbol-cache
461 Flush the contents of the symbol cache.
465 Start branch trace recording using Branch Trace Store (BTS) format.
468 Evaluate expression by using the compiler and print result.
472 Explicit commands for enabling and disabling tui mode.
475 set mpx bound on i386 and amd64
476 Support for bound table investigation on Intel MPX enabled applications.
480 Start branch trace recording using Intel Processor Trace format.
483 Print information about branch tracing internals.
485 maint btrace packet-history
486 Print the raw branch tracing data.
488 maint btrace clear-packet-history
489 Discard the stored raw branch tracing data.
492 Discard all branch tracing data. It will be fetched and processed
493 anew by the next "record" command.
498 Renamed from "set debug dwarf2-die".
500 Renamed from "show debug dwarf2-die".
503 Renamed from "set debug dwarf2-read".
504 show debug dwarf-read
505 Renamed from "show debug dwarf2-read".
507 maint set dwarf always-disassemble
508 Renamed from "maint set dwarf2 always-disassemble".
509 maint show dwarf always-disassemble
510 Renamed from "maint show dwarf2 always-disassemble".
512 maint set dwarf max-cache-age
513 Renamed from "maint set dwarf2 max-cache-age".
514 maint show dwarf max-cache-age
515 Renamed from "maint show dwarf2 max-cache-age".
518 show debug dwarf-line
519 Control display of debugging info regarding DWARF line processing.
523 Set the maximum number of candidates to be considered during
524 completion. The default value is 200. This limit allows GDB
525 to avoid generating large completion lists, the computation of
526 which can cause the debugger to become temporarily unresponsive.
528 set history remove-duplicates
529 show history remove-duplicates
530 Control the removal of duplicate history entries.
532 maint set symbol-cache-size
533 maint show symbol-cache-size
534 Control the size of the symbol cache.
536 set|show record btrace bts buffer-size
537 Set and show the size of the ring buffer used for branch tracing in
539 The obtained size may differ from the requested size. Use "info
540 record" to see the obtained buffer size.
542 set debug linux-namespaces
543 show debug linux-namespaces
544 Control display of debugging info regarding Linux namespaces.
546 set|show record btrace pt buffer-size
547 Set and show the size of the ring buffer used for branch tracing in
548 Intel Processor Trace format.
549 The obtained size may differ from the requested size. Use "info
550 record" to see the obtained buffer size.
552 maint set|show btrace pt skip-pad
553 Set and show whether PAD packets are skipped when computing the
556 * The command 'thread apply all' can now support new option '-ascending'
557 to call its specified command for all threads in ascending order.
559 * Python/Guile scripting
561 ** GDB now supports auto-loading of Python/Guile scripts contained in the
562 special section named `.debug_gdb_scripts'.
566 qXfer:btrace-conf:read
567 Return the branch trace configuration for the current thread.
569 Qbtrace-conf:bts:size
570 Set the requested ring buffer size for branch tracing in BTS format.
573 Enable Intel Procesor Trace-based branch tracing for the current
574 process. The remote stub reports support for this packet to GDB's
578 Set the requested ring buffer size for branch tracing in Intel Processor
582 Indicates a memory breakpoint instruction was executed, irrespective
583 of whether it was GDB that planted the breakpoint or the breakpoint
584 is hardcoded in the program. This is required for correct non-stop
588 Indicates the target stopped for a hardware breakpoint. This is
589 required for correct non-stop mode operation.
592 Return information about files on the remote system.
595 Return the full absolute name of the file that was executed to
596 create a process running on the remote system.
599 Select the filesystem on which vFile: operations with filename
600 arguments will operate. This is required for GDB to be able to
601 access files on remote targets where the remote stub does not
602 share a common filesystem with the inferior(s).
605 Indicates that a fork system call was executed.
608 Indicates that a vfork system call was executed.
610 vforkdone stop reason
611 Indicates that a vfork child of the specified process has executed
612 an exec or exit, allowing the vfork parent to resume execution.
614 fork-events and vfork-events features in qSupported
615 The qSupported packet allows GDB to request support for fork and
616 vfork events using new 'gdbfeatures' fork-events and vfork-events,
617 and the qSupported response can contain the corresponding
618 'stubfeatures'. Set and show commands can be used to display
619 whether these features are enabled.
621 * Extended-remote fork events
623 ** GDB now has support for fork events on extended-remote Linux
624 targets. For targets with Linux kernels 2.5.60 and later, this
625 enables follow-fork-mode and detach-on-fork for both fork and
626 vfork, as well as fork and vfork catchpoints.
628 * The info record command now shows the recording format and the
629 branch tracing configuration for the current thread when using
630 the btrace record target.
631 For the BTS format, it shows the ring buffer size.
633 * GDB now has support for DTrace USDT (Userland Static Defined
634 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
636 * GDB now supports access to vector registers on S/390 GNU/Linux
639 * Removed command line options
641 -xdb HP-UX XDB compatibility mode.
643 * Removed targets and native configurations
645 HP/PA running HP-UX hppa*-*-hpux*
646 Itanium running HP-UX ia64-*-hpux*
648 * New configure options
651 This configure option allows the user to build GDB with support for
652 Intel Processor Trace (default: auto). This requires libipt.
654 --with-libipt-prefix=PATH
655 Specify the path to the version of libipt that GDB should use.
656 $PATH/include should contain the intel-pt.h header and
657 $PATH/lib should contain the libipt.so library.
659 *** Changes in GDB 7.9.1
663 ** Xmethods can now specify a result type.
665 *** Changes in GDB 7.9
667 * GDB now supports hardware watchpoints on x86 GNU Hurd.
671 ** You can now access frame registers from Python scripts.
672 ** New attribute 'producer' for gdb.Symtab objects.
673 ** gdb.Objfile objects have a new attribute "progspace",
674 which is the gdb.Progspace object of the containing program space.
675 ** gdb.Objfile objects have a new attribute "owner".
676 ** gdb.Objfile objects have a new attribute "build_id",
677 which is the build ID generated when the file was built.
678 ** gdb.Objfile objects have a new method "add_separate_debug_file".
679 ** A new event "gdb.clear_objfiles" has been added, triggered when
680 selecting a new file to debug.
681 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
682 ** New function gdb.lookup_objfile.
684 New events which are triggered when GDB modifies the state of the
687 ** gdb.events.inferior_call_pre: Function call is about to be made.
688 ** gdb.events.inferior_call_post: Function call has just been made.
689 ** gdb.events.memory_changed: A memory location has been altered.
690 ** gdb.events.register_changed: A register has been altered.
692 * New Python-based convenience functions:
694 ** $_caller_is(name [, number_of_frames])
695 ** $_caller_matches(regexp [, number_of_frames])
696 ** $_any_caller_is(name [, number_of_frames])
697 ** $_any_caller_matches(regexp [, number_of_frames])
699 * GDB now supports the compilation and injection of source code into
700 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
701 to compile the source code to object code, and if successful, inject
702 and execute that code within the current context of the inferior.
703 Currently the C language is supported. The commands used to
704 interface with this new feature are:
706 compile code [-raw|-r] [--] [source code]
707 compile file [-raw|-r] filename
711 demangle [-l language] [--] name
712 Demangle "name" in the specified language, or the current language
713 if elided. This command is renamed from the "maint demangle" command.
714 The latter is kept as a no-op to avoid "maint demangle" being interpreted
715 as "maint demangler-warning".
717 queue-signal signal-name-or-number
718 Queue a signal to be delivered to the thread when it is resumed.
720 add-auto-load-scripts-directory directory
721 Add entries to the list of directories from which to load auto-loaded
724 maint print user-registers
725 List all currently available "user" registers.
727 compile code [-r|-raw] [--] [source code]
728 Compile, inject, and execute in the inferior the executable object
729 code produced by compiling the provided source code.
731 compile file [-r|-raw] filename
732 Compile and inject into the inferior the executable object code
733 produced by compiling the source code stored in the filename
736 * On resume, GDB now always passes the signal the program had stopped
737 for to the thread the signal was sent to, even if the user changed
738 threads before resuming. Previously GDB would often (but not
739 always) deliver the signal to the thread that happens to be current
742 * Conversely, the "signal" command now consistently delivers the
743 requested signal to the current thread. GDB now asks for
744 confirmation if the program had stopped for a signal and the user
745 switched threads meanwhile.
747 * "breakpoint always-inserted" modes "off" and "auto" merged.
749 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
750 won't remove breakpoints from the target until all threads stop,
751 even in non-stop mode. The "auto" mode has been removed, and "off"
752 is now the default mode.
756 set debug symbol-lookup
757 show debug symbol-lookup
758 Control display of debugging info regarding symbol lookup.
762 ** The -list-thread-groups command outputs an exit-code field for
763 inferiors that have exited.
767 MIPS SDE mips*-sde*-elf*
771 Support for these obsolete configurations has been removed.
773 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
774 SGI Irix-5.x mips-*-irix5*
775 SGI Irix-6.x mips-*-irix6*
776 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
777 VAX running Ultrix vax-*-ultrix*
779 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
780 and "assf"), have been removed. Use the "sharedlibrary" command, or
781 its alias "share", instead.
783 *** Changes in GDB 7.8
785 * New command line options
788 This is an alias for the --data-directory option.
790 * GDB supports printing and modifying of variable length automatic arrays
791 as specified in ISO C99.
793 * The ARM simulator now supports instruction level tracing
794 with or without disassembly.
798 GDB now has support for scripting using Guile. Whether this is
799 available is determined at configure time.
800 Guile version 2.0 or greater is required.
801 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
803 * New commands (for set/show, see "New options" below)
807 Invoke CODE by passing it to the Guile interpreter.
811 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
813 info auto-load guile-scripts [regexp]
814 Print the list of automatically loaded Guile scripts.
816 * The source command is now capable of sourcing Guile scripts.
817 This feature is dependent on the debugger being built with Guile support.
821 set print symbol-loading (off|brief|full)
822 show print symbol-loading
823 Control whether to print informational messages when loading symbol
824 information for a file. The default is "full", but when debugging
825 programs with large numbers of shared libraries the amount of output
828 set guile print-stack (none|message|full)
829 show guile print-stack
830 Show a stack trace when an error is encountered in a Guile script.
832 set auto-load guile-scripts (on|off)
833 show auto-load guile-scripts
834 Control auto-loading of Guile script files.
836 maint ada set ignore-descriptive-types (on|off)
837 maint ada show ignore-descriptive-types
838 Control whether the debugger should ignore descriptive types in Ada
839 programs. The default is not to ignore the descriptive types. See
840 the user manual for more details on descriptive types and the intended
841 usage of this option.
843 set auto-connect-native-target
845 Control whether GDB is allowed to automatically connect to the
846 native target for the run, attach, etc. commands when not connected
847 to any target yet. See also "target native" below.
849 set record btrace replay-memory-access (read-only|read-write)
850 show record btrace replay-memory-access
851 Control what memory accesses are allowed during replay.
853 maint set target-async (on|off)
854 maint show target-async
855 This controls whether GDB targets operate in synchronous or
856 asynchronous mode. Normally the default is asynchronous, if it is
857 available; but this can be changed to more easily debug problems
858 occurring only in synchronous mode.
860 set mi-async (on|off)
862 Control whether MI asynchronous mode is preferred. This supersedes
863 "set target-async" of previous GDB versions.
865 * "set target-async" is deprecated as a CLI option and is now an alias
866 for "set mi-async" (only puts MI into async mode).
868 * Background execution commands (e.g., "c&", "s&", etc.) are now
869 possible ``out of the box'' if the target supports them. Previously
870 the user would need to explicitly enable the possibility with the
871 "set target-async on" command.
873 * New features in the GDB remote stub, GDBserver
875 ** New option --debug-format=option1[,option2,...] allows one to add
876 additional text to each output. At present only timestamps
877 are supported: --debug-format=timestamps.
878 Timestamps can also be turned on with the
879 "monitor set debug-format timestamps" command from GDB.
881 * The 'record instruction-history' command now starts counting instructions
882 at one. This also affects the instruction ranges reported by the
883 'record function-call-history' command when given the /i modifier.
885 * The command 'record function-call-history' supports a new modifier '/c' to
886 indent the function names based on their call stack depth.
887 The fields for the '/i' and '/l' modifier have been reordered.
888 The source line range is now prefixed with 'at'.
889 The instruction range is now prefixed with 'inst'.
890 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
891 "record instruction-history" and "list" commands.
893 * The ranges given as arguments to the 'record function-call-history' and
894 'record instruction-history' commands are now inclusive.
896 * The btrace record target now supports the 'record goto' command.
897 For locations inside the execution trace, the back trace is computed
898 based on the information stored in the execution trace.
900 * The btrace record target supports limited reverse execution and replay.
901 The target does not record data and therefore does not allow reading
904 * The "catch syscall" command now works on s390*-linux* targets.
906 * The "compare-sections" command is no longer specific to target
907 remote. It now works with all targets.
909 * All native targets are now consistently called "native".
910 Consequently, the "target child", "target GNU", "target djgpp",
911 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
912 commands have been replaced with "target native". The QNX/NTO port
913 leaves the "procfs" target in place and adds a "native" target for
914 consistency with other ports. The impact on users should be minimal
915 as these commands previously either throwed an error, or were
916 no-ops. The target's name is visible in the output of the following
917 commands: "help target", "info target", "info files", "maint print
920 * The "target native" command now connects to the native target. This
921 can be used to launch native programs even when "set
922 auto-connect-native-target" is set to off.
924 * GDB now supports access to Intel MPX registers on GNU/Linux.
926 * Support for Intel AVX-512 registers on GNU/Linux.
927 Support displaying and modifying Intel AVX-512 registers
928 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
932 qXfer:btrace:read's annex
933 The qXfer:btrace:read packet supports a new annex 'delta' to read
934 branch trace incrementally.
938 ** Valid Python operations on gdb.Value objects representing
939 structs/classes invoke the corresponding overloaded operators if
941 ** New `Xmethods' feature in the Python API. Xmethods are
942 additional methods or replacements for existing methods of a C++
943 class. This feature is useful for those cases where a method
944 defined in C++ source code could be inlined or optimized out by
945 the compiler, making it unavailable to GDB.
948 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
950 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
951 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
952 its alias "share", instead.
954 * The commands "set remotebaud" and "show remotebaud" are no longer
955 supported. Use "set serial baud" and "show serial baud" (respectively)
960 ** A new option "-gdb-set mi-async" replaces "-gdb-set
961 target-async". The latter is left as a deprecated alias of the
962 former for backward compatibility. If the target supports it,
963 CLI background execution commands are now always possible by
964 default, independently of whether the frontend stated a
965 preference for asynchronous execution with "-gdb-set mi-async".
966 Previously "-gdb-set target-async off" affected both MI execution
967 commands and CLI execution commands.
969 *** Changes in GDB 7.7
971 * Improved support for process record-replay and reverse debugging on
972 arm*-linux* targets. Support for thumb32 and syscall instruction
973 recording has been added.
975 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
977 * GDB now supports Fission DWP file format version 2.
978 http://gcc.gnu.org/wiki/DebugFission
980 * New convenience function "$_isvoid", to check whether an expression
981 is void. A void expression is an expression where the type of the
982 result is "void". For example, some convenience variables may be
983 "void" when evaluated (e.g., "$_exitcode" before the execution of
984 the program being debugged; or an undefined convenience variable).
985 Another example, when calling a function whose return type is
988 * The "maintenance print objfiles" command now takes an optional regexp.
990 * The "catch syscall" command now works on arm*-linux* targets.
992 * GDB now consistently shows "<not saved>" when printing values of
993 registers the debug info indicates have not been saved in the frame
994 and there's nowhere to retrieve them from
995 (callee-saved/call-clobbered registers):
1000 (gdb) info registers rax
1003 Before, the former would print "<optimized out>", and the latter
1004 "*value not available*".
1006 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1011 ** Frame filters and frame decorators have been added.
1012 ** Temporary breakpoints are now supported.
1013 ** Line tables representation has been added.
1014 ** New attribute 'parent_type' for gdb.Field objects.
1015 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1016 ** New attribute 'name' for gdb.Type objects.
1020 Nios II ELF nios2*-*-elf
1021 Nios II GNU/Linux nios2*-*-linux
1022 Texas Instruments MSP430 msp430*-*-elf
1024 * Removed native configurations
1026 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1027 been removed. ELF variants of these configurations are kept supported.
1029 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1030 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1031 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1032 i[34567]86-*-openbsd3.[0-3]
1033 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1034 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1035 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1039 Like "catch throw", but catches a re-thrown exception.
1040 maint check-psymtabs
1041 Renamed from old "maint check-symtabs".
1043 Perform consistency checks on symtabs.
1044 maint expand-symtabs
1045 Expand symtabs matching an optional regexp.
1048 Display the details of GDB configure-time options.
1050 maint set|show per-command
1051 maint set|show per-command space
1052 maint set|show per-command time
1053 maint set|show per-command symtab
1054 Enable display of per-command gdb resource usage.
1056 remove-symbol-file FILENAME
1057 remove-symbol-file -a ADDRESS
1058 Remove a symbol file added via add-symbol-file. The file to remove
1059 can be identified by its filename or by an address that lies within
1060 the boundaries of this symbol file in memory.
1063 info exceptions REGEXP
1064 Display the list of Ada exceptions defined in the program being
1065 debugged. If provided, only the exceptions whose names match REGEXP
1070 set debug symfile off|on
1072 Control display of debugging info regarding reading symbol files and
1073 symbol tables within those files
1075 set print raw frame-arguments
1076 show print raw frame-arguments
1077 Set/show whether to print frame arguments in raw mode,
1078 disregarding any defined pretty-printers.
1080 set remote trace-status-packet
1081 show remote trace-status-packet
1082 Set/show the use of remote protocol qTStatus packet.
1086 Control display of debugging messages related to Nios II targets.
1090 Control whether target-assisted range stepping is enabled.
1092 set startup-with-shell
1093 show startup-with-shell
1094 Specifies whether Unix child processes are started via a shell or
1099 Use the target memory cache for accesses to the code segment. This
1100 improves performance of remote debugging (particularly disassembly).
1102 * You can now use a literal value 'unlimited' for options that
1103 interpret 0 or -1 as meaning "unlimited". E.g., "set
1104 trace-buffer-size unlimited" is now an alias for "set
1105 trace-buffer-size -1" and "set height unlimited" is now an alias for
1108 * The "set debug symtab-create" debugging option of GDB has been changed to
1109 accept a verbosity level. 0 means "off", 1 provides basic debugging
1110 output, and values of 2 or greater provides more verbose output.
1112 * New command-line options
1114 Display the details of GDB configure-time options.
1116 * The command 'tsave' can now support new option '-ctf' to save trace
1117 buffer in Common Trace Format.
1119 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1122 * GDB now implements the the C++ 'typeid' operator.
1124 * The new convenience variable $_exception holds the exception being
1125 thrown or caught at an exception-related catchpoint.
1127 * The exception-related catchpoints, like "catch throw", now accept a
1128 regular expression which can be used to filter exceptions by type.
1130 * The new convenience variable $_exitsignal is automatically set to
1131 the terminating signal number when the program being debugged dies
1132 due to an uncaught signal.
1136 ** All MI commands now accept an optional "--language" option.
1137 Support for this feature can be verified by using the "-list-features"
1138 command, which should contain "language-option".
1140 ** The new command -info-gdb-mi-command allows the user to determine
1141 whether a GDB/MI command is supported or not.
1143 ** The "^error" result record returned when trying to execute an undefined
1144 GDB/MI command now provides a variable named "code" whose content is the
1145 "undefined-command" error code. Support for this feature can be verified
1146 by using the "-list-features" command, which should contain
1147 "undefined-command-error-code".
1149 ** The -trace-save MI command can optionally save trace buffer in Common
1152 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1154 ** The command -data-list-register-values now accepts an optional
1155 "--skip-unavailable" option. When used, only the available registers
1158 ** The new command -trace-frame-collected dumps collected variables,
1159 computed expressions, tvars, memory and registers in a traceframe.
1161 ** The commands -stack-list-locals, -stack-list-arguments and
1162 -stack-list-variables now accept an option "--skip-unavailable".
1163 When used, only the available locals or arguments are displayed.
1165 ** The -exec-run command now accepts an optional "--start" option.
1166 When used, the command follows the same semantics as the "start"
1167 command, stopping the program's execution at the start of its
1168 main subprogram. Support for this feature can be verified using
1169 the "-list-features" command, which should contain
1170 "exec-run-start-option".
1172 ** The new commands -catch-assert and -catch-exceptions insert
1173 catchpoints stopping the program when Ada exceptions are raised.
1175 ** The new command -info-ada-exceptions provides the equivalent of
1176 the new "info exceptions" command.
1178 * New system-wide configuration scripts
1179 A GDB installation now provides scripts suitable for use as system-wide
1180 configuration scripts for the following systems:
1184 * GDB now supports target-assigned range stepping with remote targets.
1185 This improves the performance of stepping source lines by reducing
1186 the number of control packets from/to GDB. See "New remote packets"
1189 * GDB now understands the element 'tvar' in the XML traceframe info.
1190 It has the id of the collected trace state variables.
1192 * On S/390 targets that provide the transactional-execution feature,
1193 the program interruption transaction diagnostic block (TDB) is now
1194 represented as a number of additional "registers" in GDB.
1196 * New remote packets
1200 The vCont packet supports a new 'r' action, that tells the remote
1201 stub to step through an address range itself, without GDB
1202 involvemement at each single-step.
1204 qXfer:libraries-svr4:read's annex
1205 The previously unused annex of the qXfer:libraries-svr4:read packet
1206 is now used to support passing an argument list. The remote stub
1207 reports support for this argument list to GDB's qSupported query.
1208 The defined arguments are "start" and "prev", used to reduce work
1209 necessary for library list updating, resulting in significant
1212 * New features in the GDB remote stub, GDBserver
1214 ** GDBserver now supports target-assisted range stepping. Currently
1215 enabled on x86/x86_64 GNU/Linux targets.
1217 ** GDBserver now adds element 'tvar' in the XML in the reply to
1218 'qXfer:traceframe-info:read'. It has the id of the collected
1219 trace state variables.
1221 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1224 * New 'z' formatter for printing and examining memory, this displays the
1225 value as hexadecimal zero padded on the left to the size of the type.
1227 * GDB can now use Windows x64 unwinding data.
1229 * The "set remotebaud" command has been replaced by "set serial baud".
1230 Similarly, "show remotebaud" has been replaced by "show serial baud".
1231 The "set remotebaud" and "show remotebaud" commands are still available
1232 to provide backward compatibility with older versions of GDB.
1234 *** Changes in GDB 7.6
1236 * Target record has been renamed to record-full.
1237 Record/replay is now enabled with the "record full" command.
1238 This also affects settings that are associated with full record/replay
1239 that have been moved from "set/show record" to "set/show record full":
1241 set|show record full insn-number-max
1242 set|show record full stop-at-limit
1243 set|show record full memory-query
1245 * A new record target "record-btrace" has been added. The new target
1246 uses hardware support to record the control-flow of a process. It
1247 does not support replaying the execution, but it implements the
1248 below new commands for investigating the recorded execution log.
1249 This new recording method can be enabled using:
1253 The "record-btrace" target is only available on Intel Atom processors
1254 and requires a Linux kernel 2.6.32 or later.
1256 * Two new commands have been added for record/replay to give information
1257 about the recorded execution without having to replay the execution.
1258 The commands are only supported by "record btrace".
1260 record instruction-history prints the execution history at
1261 instruction granularity
1263 record function-call-history prints the execution history at
1264 function granularity
1266 * New native configurations
1268 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1269 FreeBSD/powerpc powerpc*-*-freebsd
1270 x86_64/Cygwin x86_64-*-cygwin*
1271 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1275 ARM AArch64 aarch64*-*-elf
1276 ARM AArch64 GNU/Linux aarch64*-*-linux
1277 Lynx 178 PowerPC powerpc-*-lynx*178
1278 x86_64/Cygwin x86_64-*-cygwin*
1279 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1281 * If the configured location of system.gdbinit file (as given by the
1282 --with-system-gdbinit option at configure time) is in the
1283 data-directory (as specified by --with-gdb-datadir at configure
1284 time) or in one of its subdirectories, then GDB will look for the
1285 system-wide init file in the directory specified by the
1286 --data-directory command-line option.
1288 * New command line options:
1290 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1291 other initialization files, unlike -nx which disables all of them.
1293 * Removed command line options
1295 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1298 * The 'ptype' and 'whatis' commands now accept an argument to control
1301 * 'info proc' now works on some core files.
1305 ** Vectors can be created with gdb.Type.vector.
1307 ** Python's atexit.register now works in GDB.
1309 ** Types can be pretty-printed via a Python API.
1311 ** Python 3 is now supported (in addition to Python 2.4 or later)
1313 ** New class gdb.Architecture exposes GDB's internal representation
1314 of architecture in the Python API.
1316 ** New method Frame.architecture returns the gdb.Architecture object
1317 corresponding to the frame's architecture.
1319 * New Python-based convenience functions:
1321 ** $_memeq(buf1, buf2, length)
1322 ** $_streq(str1, str2)
1324 ** $_regex(str, regex)
1326 * The 'cd' command now defaults to using '~' (the home directory) if not
1329 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1330 default for GCC since November 2000.
1332 * The command 'forward-search' can now be abbreviated as 'fo'.
1334 * The command 'info tracepoints' can now display 'installed on target'
1335 or 'not installed on target' for each non-pending location of tracepoint.
1337 * New configure options
1339 --enable-libmcheck/--disable-libmcheck
1340 By default, development versions are built with -lmcheck on hosts
1341 that support it, in order to help track memory corruption issues.
1342 Release versions, on the other hand, are built without -lmcheck
1343 by default. The --enable-libmcheck/--disable-libmcheck configure
1344 options allow the user to override that default.
1345 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1346 This configure option allows the user to build GDB with
1347 libbabeltrace using which GDB can read Common Trace Format data.
1349 * New commands (for set/show, see "New options" below)
1352 Catch signals. This is similar to "handle", but allows commands and
1353 conditions to be attached.
1356 List the BFDs known to GDB.
1358 python-interactive [command]
1360 Start a Python interactive prompt, or evaluate the optional command
1361 and print the result of expressions.
1364 "py" is a new alias for "python".
1366 enable type-printer [name]...
1367 disable type-printer [name]...
1368 Enable or disable type printers.
1372 ** For the Renesas Super-H architecture, the "regs" command has been removed
1373 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1378 set print type methods (on|off)
1379 show print type methods
1380 Control whether method declarations are displayed by "ptype".
1381 The default is to show them.
1383 set print type typedefs (on|off)
1384 show print type typedefs
1385 Control whether typedef definitions are displayed by "ptype".
1386 The default is to show them.
1388 set filename-display basename|relative|absolute
1389 show filename-display
1390 Control the way in which filenames is displayed.
1391 The default is "relative", which preserves previous behavior.
1393 set trace-buffer-size
1394 show trace-buffer-size
1395 Request target to change the size of trace buffer.
1397 set remote trace-buffer-size-packet auto|on|off
1398 show remote trace-buffer-size-packet
1399 Control the use of the remote protocol `QTBuffer:size' packet.
1403 Control display of debugging messages related to ARM AArch64.
1406 set debug coff-pe-read
1407 show debug coff-pe-read
1408 Control display of debugging messages related to reading of COFF/PE
1413 Control display of debugging messages related to Mach-O symbols
1416 set debug notification
1417 show debug notification
1418 Control display of debugging info for async remote notification.
1422 ** Command parameter changes are now notified using new async record
1423 "=cmd-param-changed".
1424 ** Trace frame changes caused by command "tfind" are now notified using
1425 new async record "=traceframe-changed".
1426 ** The creation, deletion and modification of trace state variables
1427 are now notified using new async records "=tsv-created",
1428 "=tsv-deleted" and "=tsv-modified".
1429 ** The start and stop of process record are now notified using new
1430 async record "=record-started" and "=record-stopped".
1431 ** Memory changes are now notified using new async record
1433 ** The data-disassemble command response will include a "fullname" field
1434 containing the absolute file name when source has been requested.
1435 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1436 command, to allow pattern filling of memory areas.
1437 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1438 library load/unload events.
1439 ** The response to breakpoint commands and breakpoint async records
1440 includes an "installed" field containing a boolean state about each
1441 non-pending tracepoint location is whether installed on target or not.
1442 ** Output of the "-trace-status" command includes a "trace-file" field
1443 containing the name of the trace file being examined. This field is
1444 optional, and only present when examining a trace file.
1445 ** The "fullname" field is now always present along with the "file" field,
1446 even if the file cannot be found by GDB.
1448 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1449 You must have the LZMA library available when configuring GDB for this
1450 feature to be enabled. For more information, see:
1451 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1453 * New remote packets
1456 Set the size of trace buffer. The remote stub reports support for this
1457 packet to gdb's qSupported query.
1460 Enable Branch Trace Store (BTS)-based branch tracing for the current
1461 thread. The remote stub reports support for this packet to gdb's
1465 Disable branch tracing for the current thread. The remote stub reports
1466 support for this packet to gdb's qSupported query.
1469 Read the traced branches for the current thread. The remote stub
1470 reports support for this packet to gdb's qSupported query.
1472 *** Changes in GDB 7.5
1474 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1475 for more x32 ABI info.
1477 * GDB now supports access to MIPS DSP registers on Linux targets.
1479 * GDB now supports debugging microMIPS binaries.
1481 * The "info os" command on GNU/Linux can now display information on
1482 several new classes of objects managed by the operating system:
1483 "info os procgroups" lists process groups
1484 "info os files" lists file descriptors
1485 "info os sockets" lists internet-domain sockets
1486 "info os shm" lists shared-memory regions
1487 "info os semaphores" lists semaphores
1488 "info os msg" lists message queues
1489 "info os modules" lists loaded kernel modules
1491 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1492 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1493 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1494 options and inspect the probe arguments using the new $_probe_arg family
1495 of convenience variables. You can obtain more information about SystemTap
1496 in <http://sourceware.org/systemtap/>.
1498 * GDB now supports reversible debugging on ARM, it allows you to
1499 debug basic ARM and THUMB instructions, and provides
1500 record/replay support.
1502 * The option "symbol-reloading" has been deleted as it is no longer used.
1506 ** GDB commands implemented in Python can now be put in command class
1509 ** The "maint set python print-stack on|off" is now deleted.
1511 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1512 apply "flag enum"-style pretty-printing to any enum.
1514 ** gdb.lookup_symbol can now work when there is no current frame.
1516 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1517 the source at which the symbol was defined.
1519 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1520 method 'value'. The former indicates whether the symbol needs a
1521 frame in order to compute its value, and the latter computes the
1524 ** A new method 'referenced_value' on gdb.Value objects which can
1525 dereference pointer as well as C++ reference values.
1527 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1528 which return the global and static blocks (as gdb.Block objects),
1529 of the underlying symbol table, respectively.
1531 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1532 object associated with a PC value.
1534 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1535 of the address range occupied by code for the current source line.
1537 * Go language support.
1538 GDB now supports debugging programs written in the Go programming
1541 * GDBserver now supports stdio connections.
1542 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1544 * The binary "gdbtui" can no longer be built or installed.
1545 Use "gdb -tui" instead.
1547 * GDB will now print "flag" enums specially. A flag enum is one where
1548 all the enumerator values have no bits in common when pairwise
1549 "and"ed. When printing a value whose type is a flag enum, GDB will
1550 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1551 (gdb) print (enum E) 3
1554 * The filename part of a linespec will now match trailing components
1555 of a source file name. For example, "break gcc/expr.c:1000" will
1556 now set a breakpoint in build/gcc/expr.c, but not
1557 build/libcpp/expr.c.
1559 * The "info proc" and "generate-core-file" commands will now also
1560 work on remote targets connected to GDBserver on Linux.
1562 * The command "info catch" has been removed. It has been disabled
1563 since December 2007.
1565 * The "catch exception" and "catch assert" commands now accept
1566 a condition at the end of the command, much like the "break"
1567 command does. For instance:
1569 (gdb) catch exception Constraint_Error if Barrier = True
1571 Previously, it was possible to add a condition to such catchpoints,
1572 but it had to be done as a second step, after the catchpoint had been
1573 created, using the "condition" command.
1575 * The "info static-tracepoint-marker" command will now also work on
1576 native Linux targets with in-process agent.
1578 * GDB can now set breakpoints on inlined functions.
1580 * The .gdb_index section has been updated to include symbols for
1581 inlined functions. GDB will ignore older .gdb_index sections by
1582 default, which could cause symbol files to be loaded more slowly
1583 until their .gdb_index sections can be recreated. The new command
1584 "set use-deprecated-index-sections on" will cause GDB to use any older
1585 .gdb_index sections it finds. This will restore performance, but the
1586 ability to set breakpoints on inlined functions will be lost in symbol
1587 files with older .gdb_index sections.
1589 The .gdb_index section has also been updated to record more information
1590 about each symbol. This speeds up the "info variables", "info functions"
1591 and "info types" commands when used with programs having the .gdb_index
1592 section, as well as speeding up debugging with shared libraries using
1593 the .gdb_index section.
1595 * Ada support for GDB/MI Variable Objects has been added.
1597 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1602 ** New command -info-os is the MI equivalent of "info os".
1604 ** Output logs ("set logging" and related) now include MI output.
1608 ** "set use-deprecated-index-sections on|off"
1609 "show use-deprecated-index-sections on|off"
1610 Controls the use of deprecated .gdb_index sections.
1612 ** "catch load" and "catch unload" can be used to stop when a shared
1613 library is loaded or unloaded, respectively.
1615 ** "enable count" can be used to auto-disable a breakpoint after
1618 ** "info vtbl" can be used to show the virtual method tables for
1619 C++ and Java objects.
1621 ** "explore" and its sub commands "explore value" and "explore type"
1622 can be used to recursively explore values and types of
1623 expressions. These commands are available only if GDB is
1624 configured with '--with-python'.
1626 ** "info auto-load" shows status of all kinds of auto-loaded files,
1627 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1628 sequences of commands files, "info auto-load python-scripts"
1629 shows status of auto-loading Python script files,
1630 "info auto-load local-gdbinit" shows status of loading init file
1631 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1632 status of inferior specific thread debugging shared library loading.
1634 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1635 and "show auto-load-scripts" commands have been deprecated, use their
1636 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1637 and "show auto-load python-scripts" counterparts instead.
1639 ** "dprintf location,format,args..." creates a dynamic printf, which
1640 is basically a breakpoint that does a printf and immediately
1641 resumes your program's execution, so it is like a printf that you
1642 can insert dynamically at runtime instead of at compiletime.
1644 ** "set print symbol"
1646 Controls whether GDB attempts to display the symbol, if any,
1647 corresponding to addresses it prints. This defaults to "on", but
1648 you can set it to "off" to restore GDB's previous behavior.
1650 * Deprecated commands
1652 ** For the Renesas Super-H architecture, the "regs" command has been
1653 deprecated, and "info all-registers" should be used instead.
1657 Renesas RL78 rl78-*-elf
1658 HP OpenVMS ia64 ia64-hp-openvms*
1660 * GDBserver supports evaluation of breakpoint conditions. When
1661 support is advertised by GDBserver, GDB may be told to send the
1662 breakpoint conditions in bytecode form to GDBserver. GDBserver
1663 will only report the breakpoint trigger to GDB when its condition
1668 set mips compression
1669 show mips compression
1670 Select the compressed ISA encoding used in functions that have no symbol
1671 information available. The encoding can be set to either of:
1674 and is updated automatically from ELF file flags if available.
1676 set breakpoint condition-evaluation
1677 show breakpoint condition-evaluation
1678 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1679 GDBserver ("target"). Default option "auto" chooses the most efficient
1681 This option can improve debugger efficiency depending on the speed of the
1685 Disable auto-loading globally.
1688 Show auto-loading setting of all kinds of auto-loaded files.
1690 set auto-load gdb-scripts on|off
1691 show auto-load gdb-scripts
1692 Control auto-loading of GDB canned sequences of commands files.
1694 set auto-load python-scripts on|off
1695 show auto-load python-scripts
1696 Control auto-loading of Python script files.
1698 set auto-load local-gdbinit on|off
1699 show auto-load local-gdbinit
1700 Control loading of init file (.gdbinit) from current directory.
1702 set auto-load libthread-db on|off
1703 show auto-load libthread-db
1704 Control auto-loading of inferior specific thread debugging shared library.
1706 set auto-load scripts-directory <dir1>[:<dir2>...]
1707 show auto-load scripts-directory
1708 Set a list of directories from which to load auto-loaded scripts.
1709 Automatically loaded Python scripts and GDB scripts are located in one
1710 of the directories listed by this option.
1711 The delimiter (':' above) may differ according to the host platform.
1713 set auto-load safe-path <dir1>[:<dir2>...]
1714 show auto-load safe-path
1715 Set a list of directories from which it is safe to auto-load files.
1716 The delimiter (':' above) may differ according to the host platform.
1718 set debug auto-load on|off
1719 show debug auto-load
1720 Control display of debugging info for auto-loading the files above.
1722 set dprintf-style gdb|call|agent
1724 Control the way in which a dynamic printf is performed; "gdb"
1725 requests a GDB printf command, while "call" causes dprintf to call a
1726 function in the inferior. "agent" requests that the target agent
1727 (such as GDBserver) do the printing.
1729 set dprintf-function <expr>
1730 show dprintf-function
1731 set dprintf-channel <expr>
1732 show dprintf-channel
1733 Set the function and optional first argument to the call when using
1734 the "call" style of dynamic printf.
1736 set disconnected-dprintf on|off
1737 show disconnected-dprintf
1738 Control whether agent-style dynamic printfs continue to be in effect
1739 after GDB disconnects.
1741 * New configure options
1743 --with-auto-load-dir
1744 Configure default value for the 'set auto-load scripts-directory'
1745 setting above. It defaults to '$debugdir:$datadir/auto-load',
1746 $debugdir representing global debugging info directories (available
1747 via 'show debug-file-directory') and $datadir representing GDB's data
1748 directory (available via 'show data-directory').
1750 --with-auto-load-safe-path
1751 Configure default value for the 'set auto-load safe-path' setting
1752 above. It defaults to the --with-auto-load-dir setting.
1754 --without-auto-load-safe-path
1755 Set 'set auto-load safe-path' to '/', effectively disabling this
1758 * New remote packets
1760 z0/z1 conditional breakpoints extension
1762 The z0/z1 breakpoint insertion packets have been extended to carry
1763 a list of conditional expressions over to the remote stub depending on the
1764 condition evaluation mode. The use of this extension can be controlled
1765 via the "set remote conditional-breakpoints-packet" command.
1769 Specify the signals which the remote stub may pass to the debugged
1770 program without GDB involvement.
1772 * New command line options
1774 --init-command=FILE, -ix Like --command, -x but execute it
1775 before loading inferior.
1776 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1777 execute it before loading inferior.
1779 *** Changes in GDB 7.4
1781 * GDB now handles ambiguous linespecs more consistently; the existing
1782 FILE:LINE support has been expanded to other types of linespecs. A
1783 breakpoint will now be set on all matching locations in all
1784 inferiors, and locations will be added or removed according to
1787 * GDB now allows you to skip uninteresting functions and files when
1788 stepping with the "skip function" and "skip file" commands.
1790 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1791 and "show remote hardware-watchpoint-length-limit". These allows to
1792 set or show the maximum length limit (in bytes) of a remote
1793 target hardware watchpoint.
1795 This allows e.g. to use "unlimited" hardware watchpoints with the
1796 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1797 watchpoints are slower than real hardware watchpoints but are
1798 significantly faster than gdb software watchpoints.
1802 ** The register_pretty_printer function in module gdb.printing now takes
1803 an optional `replace' argument. If True, the new printer replaces any
1806 ** The "maint set python print-stack on|off" command has been
1807 deprecated and will be deleted in GDB 7.5.
1808 A new command: "set python print-stack none|full|message" has
1809 replaced it. Additionally, the default for "print-stack" is
1810 now "message", which just prints the error message without
1813 ** A prompt substitution hook (prompt_hook) is now available to the
1816 ** A new Python module, gdb.prompt has been added to the GDB Python
1817 modules library. This module provides functionality for
1818 escape sequences in prompts (used by set/show
1819 extended-prompt). These escape sequences are replaced by their
1820 corresponding value.
1822 ** Python commands and convenience-functions located in
1823 'data-directory'/python/gdb/command and
1824 'data-directory'/python/gdb/function are now automatically loaded
1827 ** Blocks now provide four new attributes. global_block and
1828 static_block will return the global and static blocks
1829 respectively. is_static and is_global are boolean attributes
1830 that indicate if the block is one of those two types.
1832 ** Symbols now provide the "type" attribute, the type of the symbol.
1834 ** The "gdb.breakpoint" function has been deprecated in favor of
1837 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1838 of a function. This class is based on the "finish" command
1839 available in the CLI.
1841 ** Type objects for struct and union types now allow access to
1842 the fields using standard Python dictionary (mapping) methods.
1843 For example, "some_type['myfield']" now works, as does
1844 "some_type.items()".
1846 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1849 ** A new function, "deep_items" has been added to the gdb.types
1850 module in the GDB Python modules library. This function returns
1851 an iterator over the fields of a struct or union type. Unlike
1852 the standard Python "iteritems" method, it will recursively traverse
1853 any anonymous fields.
1857 ** "*stopped" events can report several new "reason"s, such as
1860 ** Breakpoint changes are now notified using new async records, like
1861 "=breakpoint-modified".
1863 ** New command -ada-task-info.
1865 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1866 $sdir specifies the default system locations of shared libraries.
1867 $pdir specifies the directory where the libpthread used by the application
1870 GDB no longer looks in $sdir and $pdir after it has searched the directories
1871 mentioned in libthread-db-search-path. If you want to search those
1872 directories, they must be specified in libthread-db-search-path.
1873 The default value of libthread-db-search-path on GNU/Linux and Solaris
1874 systems is now "$sdir:$pdir".
1876 $pdir is not supported by gdbserver, it is currently ignored.
1877 $sdir is supported by gdbserver.
1879 * New configure option --with-iconv-bin.
1880 When using the internationalization support like the one in the GNU C
1881 library, GDB will invoke the "iconv" program to get a list of supported
1882 character sets. If this program lives in a non-standard location, one can
1883 use this option to specify where to find it.
1885 * When natively debugging programs on PowerPC BookE processors running
1886 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1887 watchpoints, which specify a mask in addition to an address to watch.
1888 The mask specifies that some bits of an address (the bits which are
1889 reset in the mask) should be ignored when matching the address accessed
1890 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1891 section in the user manual for more details.
1893 * The new option --once causes GDBserver to stop listening for connections once
1894 the first connection is made. The listening port used by GDBserver will
1895 become available after that.
1897 * New commands "info macros" and "alias" have been added.
1899 * New function parameters suffix @entry specifies value of function parameter
1900 at the time the function got called. Entry values are available only since
1906 "!" is now an alias of the "shell" command.
1907 Note that no space is needed between "!" and SHELL COMMAND.
1911 watch EXPRESSION mask MASK_VALUE
1912 The watch command now supports the mask argument which allows creation
1913 of masked watchpoints, if the current architecture supports this feature.
1915 info auto-load-scripts [REGEXP]
1916 This command was formerly named "maintenance print section-scripts".
1917 It is now generally useful and is no longer a maintenance-only command.
1919 info macro [-all] [--] MACRO
1920 The info macro command has new options `-all' and `--'. The first for
1921 printing all definitions of a macro. The second for explicitly specifying
1922 the end of arguments and the beginning of the macro name in case the macro
1923 name starts with a hyphen.
1925 collect[/s] EXPRESSIONS
1926 The tracepoint collect command now takes an optional modifier "/s"
1927 that directs it to dereference pointer-to-character types and
1928 collect the bytes of memory up to a zero byte. The behavior is
1929 similar to what you see when you use the regular print command on a
1930 string. An optional integer following the "/s" sets a bound on the
1931 number of bytes that will be collected.
1934 The trace start command now interprets any supplied arguments as a
1935 note to be recorded with the trace run, with an effect similar to
1936 setting the variable trace-notes.
1939 The trace stop command now interprets any arguments as a note to be
1940 mentioned along with the tstatus report that the trace was stopped
1941 with a command. The effect is similar to setting the variable
1944 * Tracepoints can now be enabled and disabled at any time after a trace
1945 experiment has been started using the standard "enable" and "disable"
1946 commands. It is now possible to start a trace experiment with no enabled
1947 tracepoints; GDB will display a warning, but will allow the experiment to
1948 begin, assuming that tracepoints will be enabled as needed while the trace
1951 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1952 locations with 4-byte instructions, when they were previously
1953 limited to locations with instructions of 5 bytes or longer.
1957 set debug dwarf2-read
1958 show debug dwarf2-read
1959 Turns on or off display of debugging messages related to reading
1960 DWARF debug info. The default is off.
1962 set debug symtab-create
1963 show debug symtab-create
1964 Turns on or off display of debugging messages related to symbol table
1965 creation. The default is off.
1968 show extended-prompt
1969 Set the GDB prompt, and allow escape sequences to be inserted to
1970 display miscellaneous information (see 'help set extended-prompt'
1971 for the list of sequences). This prompt (and any information
1972 accessed through the escape sequences) is updated every time the
1973 prompt is displayed.
1975 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1976 show print entry-values
1977 Set printing of frame argument values at function entry. In some cases
1978 GDB can determine the value of function argument which was passed by the
1979 function caller, even if the value was modified inside the called function.
1981 set debug entry-values
1982 show debug entry-values
1983 Control display of debugging info for determining frame argument values at
1984 function entry and virtual tail call frames.
1986 set basenames-may-differ
1987 show basenames-may-differ
1988 Set whether a source file may have multiple base names.
1989 (A "base name" is the name of a file with the directory part removed.
1990 Example: The base name of "/home/user/hello.c" is "hello.c".)
1991 If set, GDB will canonicalize file names (e.g., expand symlinks)
1992 before comparing them. Canonicalization is an expensive operation,
1993 but it allows the same file be known by more than one base name.
1994 If not set (the default), all source files are assumed to have just
1995 one base name, and gdb will do file name comparisons more efficiently.
2001 Set a user name and notes for the current and any future trace runs.
2002 This is useful for long-running and/or disconnected traces, to
2003 inform others (or yourself) as to who is running the trace, supply
2004 contact information, or otherwise explain what is going on.
2006 set trace-stop-notes
2007 show trace-stop-notes
2008 Set a note attached to the trace run, that is displayed when the
2009 trace has been stopped by a tstop command. This is useful for
2010 instance as an explanation, if you are stopping a trace run that was
2011 started by someone else.
2013 * New remote packets
2017 Dynamically enable a tracepoint in a started trace experiment.
2021 Dynamically disable a tracepoint in a started trace experiment.
2025 Set the user and notes of the trace run.
2029 Query the current status of a tracepoint.
2033 Query the minimum length of instruction at which a fast tracepoint may
2036 * Dcache size (number of lines) and line-size are now runtime-configurable
2037 via "set dcache line" and "set dcache line-size" commands.
2041 Texas Instruments TMS320C6x tic6x-*-*
2045 Renesas RL78 rl78-*-elf
2047 *** Changes in GDB 7.3.1
2049 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2051 *** Changes in GDB 7.3
2053 * GDB has a new command: "thread find [REGEXP]".
2054 It finds the thread id whose name, target id, or thread extra info
2055 matches the given regular expression.
2057 * The "catch syscall" command now works on mips*-linux* targets.
2059 * The -data-disassemble MI command now supports modes 2 and 3 for
2060 dumping the instruction opcodes.
2062 * New command line options
2064 -data-directory DIR Specify DIR as the "data-directory".
2065 This is mostly for testing purposes.
2067 * The "maint set python auto-load on|off" command has been renamed to
2068 "set auto-load-scripts on|off".
2070 * GDB has a new command: "set directories".
2071 It is like the "dir" command except that it replaces the
2072 source path list instead of augmenting it.
2074 * GDB now understands thread names.
2076 On GNU/Linux, "info threads" will display the thread name as set by
2077 prctl or pthread_setname_np.
2079 There is also a new command, "thread name", which can be used to
2080 assign a name internally for GDB to display.
2083 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2084 has been integrated into GDB.
2088 ** The function gdb.Write now accepts an optional keyword 'stream'.
2089 This keyword, when provided, will direct the output to either
2090 stdout, stderr, or GDB's logging output.
2092 ** Parameters can now be be sub-classed in Python, and in particular
2093 you may implement the get_set_doc and get_show_doc functions.
2094 This improves how Parameter set/show documentation is processed
2095 and allows for more dynamic content.
2097 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2098 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2099 have an is_valid method.
2101 ** Breakpoints can now be sub-classed in Python, and in particular
2102 you may implement a 'stop' function that is executed each time
2103 the inferior reaches that breakpoint.
2105 ** New function gdb.lookup_global_symbol looks up a global symbol.
2107 ** GDB values in Python are now callable if the value represents a
2108 function. For example, if 'some_value' represents a function that
2109 takes two integer parameters and returns a value, you can call
2110 that function like so:
2112 result = some_value (10,20)
2114 ** Module gdb.types has been added.
2115 It contains a collection of utilities for working with gdb.Types objects:
2116 get_basic_type, has_field, make_enum_dict.
2118 ** Module gdb.printing has been added.
2119 It contains utilities for writing and registering pretty-printers.
2120 New classes: PrettyPrinter, SubPrettyPrinter,
2121 RegexpCollectionPrettyPrinter.
2122 New function: register_pretty_printer.
2124 ** New commands "info pretty-printers", "enable pretty-printer" and
2125 "disable pretty-printer" have been added.
2127 ** gdb.parameter("directories") is now available.
2129 ** New function gdb.newest_frame returns the newest frame in the
2132 ** The gdb.InferiorThread class has a new "name" attribute. This
2133 holds the thread's name.
2135 ** Python Support for Inferior events.
2136 Python scripts can add observers to be notified of events
2137 occurring in the process being debugged.
2138 The following events are currently supported:
2139 - gdb.events.cont Continue event.
2140 - gdb.events.exited Inferior exited event.
2141 - gdb.events.stop Signal received, and Breakpoint hit events.
2145 ** GDB now puts template parameters in scope when debugging in an
2146 instantiation. For example, if you have:
2148 template<int X> int func (void) { return X; }
2150 then if you step into func<5>, "print X" will show "5". This
2151 feature requires proper debuginfo support from the compiler; it
2152 was added to GCC 4.5.
2154 ** The motion commands "next", "finish", "until", and "advance" now
2155 work better when exceptions are thrown. In particular, GDB will
2156 no longer lose control of the inferior; instead, the GDB will
2157 stop the inferior at the point at which the exception is caught.
2158 This functionality requires a change in the exception handling
2159 code that was introduced in GCC 4.5.
2161 * GDB now follows GCC's rules on accessing volatile objects when
2162 reading or writing target state during expression evaluation.
2163 One notable difference to prior behavior is that "print x = 0"
2164 no longer generates a read of x; the value of the assignment is
2165 now always taken directly from the value being assigned.
2167 * GDB now has some support for using labels in the program's source in
2168 linespecs. For instance, you can use "advance label" to continue
2169 execution to a label.
2171 * GDB now has support for reading and writing a new .gdb_index
2172 section. This section holds a fast index of DWARF debugging
2173 information and can be used to greatly speed up GDB startup and
2174 operation. See the documentation for `save gdb-index' for details.
2176 * The "watch" command now accepts an optional "-location" argument.
2177 When used, this causes GDB to watch the memory referred to by the
2178 expression. Such a watchpoint is never deleted due to it going out
2181 * GDB now supports thread debugging of core dumps on GNU/Linux.
2183 GDB now activates thread debugging using the libthread_db library
2184 when debugging GNU/Linux core dumps, similarly to when debugging
2185 live processes. As a result, when debugging a core dump file, GDB
2186 is now able to display pthread_t ids of threads. For example, "info
2187 threads" shows the same output as when debugging the process when it
2188 was live. In earlier releases, you'd see something like this:
2191 * 1 LWP 6780 main () at main.c:10
2193 While now you see this:
2196 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2198 It is also now possible to inspect TLS variables when debugging core
2201 When debugging a core dump generated on a machine other than the one
2202 used to run GDB, you may need to point GDB at the correct
2203 libthread_db library with the "set libthread-db-search-path"
2204 command. See the user manual for more details on this command.
2206 * When natively debugging programs on PowerPC BookE processors running
2207 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2208 which stop execution of the inferior whenever it executes an instruction
2209 at any address within the specified range. See the "PowerPC Embedded"
2210 section in the user manual for more details.
2212 * New features in the GDB remote stub, GDBserver
2214 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2215 and i686 LynxOS (version 5.x).
2217 ** GDBserver is now supported on Blackfin Linux.
2219 * New native configurations
2221 ia64 HP-UX ia64-*-hpux*
2225 Analog Devices, Inc. Blackfin Processor bfin-*
2227 * Ada task switching is now supported on sparc-elf targets when
2228 debugging a program using the Ravenscar Profile. For more information,
2229 see the "Tasking Support when using the Ravenscar Profile" section
2230 in the GDB user manual.
2232 * Guile support was removed.
2234 * New features in the GNU simulator
2236 ** The --map-info flag lists all known core mappings.
2238 ** CFI flashes may be simulated via the "cfi" device.
2240 *** Changes in GDB 7.2
2242 * Shared library support for remote targets by default
2244 When GDB is configured for a generic, non-OS specific target, like
2245 for example, --target=arm-eabi or one of the many *-*-elf targets,
2246 GDB now queries remote stubs for loaded shared libraries using the
2247 `qXfer:libraries:read' packet. Previously, shared library support
2248 was always disabled for such configurations.
2252 ** Argument Dependent Lookup (ADL)
2254 In C++ ADL lookup directs function search to the namespaces of its
2255 arguments even if the namespace has not been imported.
2265 Here the compiler will search for `foo' in the namespace of 'b'
2266 and find A::foo. GDB now supports this. This construct is commonly
2267 used in the Standard Template Library for operators.
2269 ** Improved User Defined Operator Support
2271 In addition to member operators, GDB now supports lookup of operators
2272 defined in a namespace and imported with a `using' directive, operators
2273 defined in the global scope, operators imported implicitly from an
2274 anonymous namespace, and the ADL operators mentioned in the previous
2276 GDB now also supports proper overload resolution for all the previously
2277 mentioned flavors of operators.
2279 ** static const class members
2281 Printing of static const class members that are initialized in the
2282 class definition has been fixed.
2284 * Windows Thread Information Block access.
2286 On Windows targets, GDB now supports displaying the Windows Thread
2287 Information Block (TIB) structure. This structure is visible either
2288 by using the new command `info w32 thread-information-block' or, by
2289 dereferencing the new convenience variable named `$_tlb', a
2290 thread-specific pointer to the TIB. This feature is also supported
2291 when remote debugging using GDBserver.
2293 * Static tracepoints
2295 Static tracepoints are calls in the user program into a tracing
2296 library. One such library is a port of the LTTng kernel tracer to
2297 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2298 When debugging with GDBserver, GDB now supports combining the GDB
2299 tracepoint machinery with such libraries. For example: the user can
2300 use GDB to probe a static tracepoint marker (a call from the user
2301 program into the tracing library) with the new "strace" command (see
2302 "New commands" below). This creates a "static tracepoint" in the
2303 breakpoint list, that can be manipulated with the same feature set
2304 as fast and regular tracepoints. E.g., collect registers, local and
2305 global variables, collect trace state variables, and define
2306 tracepoint conditions. In addition, the user can collect extra
2307 static tracepoint marker specific data, by collecting the new
2308 $_sdata internal variable. When analyzing the trace buffer, you can
2309 inspect $_sdata like any other variable available to GDB. For more
2310 information, see the "Tracepoints" chapter in GDB user manual. New
2311 remote packets have been defined to support static tracepoints, see
2312 the "New remote packets" section below.
2314 * Better reconstruction of tracepoints after disconnected tracing
2316 GDB will attempt to download the original source form of tracepoint
2317 definitions when starting a trace run, and then will upload these
2318 upon reconnection to the target, resulting in a more accurate
2319 reconstruction of the tracepoints that are in use on the target.
2323 You can now exercise direct control over the ways that GDB can
2324 affect your program. For instance, you can disallow the setting of
2325 breakpoints, so that the program can run continuously (assuming
2326 non-stop mode). In addition, the "observer" variable is available
2327 to switch all of the different controls; in observer mode, GDB
2328 cannot affect the target's behavior at all, which is useful for
2329 tasks like diagnosing live systems in the field.
2331 * The new convenience variable $_thread holds the number of the
2334 * New remote packets
2338 Return the address of the Windows Thread Information Block of a given thread.
2342 In response to several of the tracepoint packets, the target may now
2343 also respond with a number of intermediate `qRelocInsn' request
2344 packets before the final result packet, to have GDB handle
2345 relocating an instruction to execute at a different address. This
2346 is particularly useful for stubs that support fast tracepoints. GDB
2347 reports support for this feature in the qSupported packet.
2351 List static tracepoint markers in the target program.
2355 List static tracepoint markers at a given address in the target
2358 qXfer:statictrace:read
2360 Read the static trace data collected (by a `collect $_sdata'
2361 tracepoint action). The remote stub reports support for this packet
2362 to gdb's qSupported query.
2366 Send the current settings of GDB's permission flags.
2370 Send part of the source (textual) form of a tracepoint definition,
2371 which includes location, conditional, and action list.
2373 * The source command now accepts a -s option to force searching for the
2374 script in the source search path even if the script name specifies
2377 * New features in the GDB remote stub, GDBserver
2379 - GDBserver now support tracepoints (including fast tracepoints, and
2380 static tracepoints). The feature is currently supported by the
2381 i386-linux and amd64-linux builds. See the "Tracepoints support
2382 in gdbserver" section in the manual for more information.
2384 GDBserver JIT compiles the tracepoint's conditional agent
2385 expression bytecode into native code whenever possible for low
2386 overhead dynamic tracepoints conditionals. For such tracepoints,
2387 an expression that examines program state is evaluated when the
2388 tracepoint is reached, in order to determine whether to capture
2389 trace data. If the condition is simple and false, processing the
2390 tracepoint finishes very quickly and no data is gathered.
2392 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2393 for static tracepoints support.
2395 - GDBserver now supports x86_64 Windows 64-bit debugging.
2397 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2398 it understands register description.
2400 * The --batch flag now disables pagination and queries.
2402 * X86 general purpose registers
2404 GDB now supports reading/writing byte, word and double-word x86
2405 general purpose registers directly. This means you can use, say,
2406 $ah or $ax to refer, respectively, to the byte register AH and
2407 16-bit word register AX that are actually portions of the 32-bit
2408 register EAX or 64-bit register RAX.
2410 * The `commands' command now accepts a range of breakpoints to modify.
2411 A plain `commands' following a command that creates multiple
2412 breakpoints affects all the breakpoints set by that command. This
2413 applies to breakpoints set by `rbreak', and also applies when a
2414 single `break' command creates multiple breakpoints (e.g.,
2415 breakpoints on overloaded c++ functions).
2417 * The `rbreak' command now accepts a filename specification as part of
2418 its argument, limiting the functions selected by the regex to those
2419 in the specified file.
2421 * Support for remote debugging Windows and SymbianOS shared libraries
2422 from Unix hosts has been improved. Non Windows GDB builds now can
2423 understand target reported file names that follow MS-DOS based file
2424 system semantics, such as file names that include drive letters and
2425 use the backslash character as directory separator. This makes it
2426 possible to transparently use the "set sysroot" and "set
2427 solib-search-path" on Unix hosts to point as host copies of the
2428 target's shared libraries. See the new command "set
2429 target-file-system-kind" described below, and the "Commands to
2430 specify files" section in the user manual for more information.
2434 eval template, expressions...
2435 Convert the values of one or more expressions under the control
2436 of the string template to a command line, and call it.
2438 set target-file-system-kind unix|dos-based|auto
2439 show target-file-system-kind
2440 Set or show the assumed file system kind for target reported file
2443 save breakpoints <filename>
2444 Save all current breakpoint definitions to a file suitable for use
2445 in a later debugging session. To read the saved breakpoint
2446 definitions, use the `source' command.
2448 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2451 info static-tracepoint-markers
2452 Display information about static tracepoint markers in the target.
2454 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2455 Define a static tracepoint by probing a marker at the given
2456 function, line, address, or marker ID.
2460 Enable and disable observer mode.
2462 set may-write-registers on|off
2463 set may-write-memory on|off
2464 set may-insert-breakpoints on|off
2465 set may-insert-tracepoints on|off
2466 set may-insert-fast-tracepoints on|off
2467 set may-interrupt on|off
2468 Set individual permissions for GDB effects on the target. Note that
2469 some of these settings can have undesirable or surprising
2470 consequences, particularly when changed in the middle of a session.
2471 For instance, disabling the writing of memory can prevent
2472 breakpoints from being inserted, cause single-stepping to fail, or
2473 even crash your program, if you disable after breakpoints have been
2474 inserted. However, GDB should not crash.
2476 set record memory-query on|off
2477 show record memory-query
2478 Control whether to stop the inferior if memory changes caused
2479 by an instruction cannot be recorded.
2484 The disassemble command now supports "start,+length" form of two arguments.
2488 ** GDB now provides a new directory location, called the python directory,
2489 where Python scripts written for GDB can be installed. The location
2490 of that directory is <data-directory>/python, where <data-directory>
2491 is the GDB data directory. For more details, see section `Scripting
2492 GDB using Python' in the manual.
2494 ** The GDB Python API now has access to breakpoints, symbols, symbol
2495 tables, program spaces, inferiors, threads and frame's code blocks.
2496 Additionally, GDB Parameters can now be created from the API, and
2497 manipulated via set/show in the CLI.
2499 ** New functions gdb.target_charset, gdb.target_wide_charset,
2500 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2502 ** New exception gdb.GdbError.
2504 ** Pretty-printers are now also looked up in the current program space.
2506 ** Pretty-printers can now be individually enabled and disabled.
2508 ** GDB now looks for names of Python scripts to auto-load in a
2509 special section named `.debug_gdb_scripts', in addition to looking
2510 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2512 * Tracepoint actions were unified with breakpoint commands. In particular,
2513 there are no longer differences in "info break" output for breakpoints and
2514 tracepoints and the "commands" command can be used for both tracepoints and
2515 regular breakpoints.
2519 ARM Symbian arm*-*-symbianelf*
2521 * D language support.
2522 GDB now supports debugging programs written in the D programming
2525 * GDB now supports the extended ptrace interface for PowerPC which is
2526 available since Linux kernel version 2.6.34. This automatically enables
2527 any hardware breakpoints and additional hardware watchpoints available in
2528 the processor. The old ptrace interface exposes just one hardware
2529 watchpoint and no hardware breakpoints.
2531 * GDB is now able to use the Data Value Compare (DVC) register available on
2532 embedded PowerPC processors to implement in hardware simple watchpoint
2533 conditions of the form:
2535 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2537 This works in native GDB running on Linux kernels with the extended ptrace
2538 interface mentioned above.
2540 *** Changes in GDB 7.1
2544 ** Namespace Support
2546 GDB now supports importing of namespaces in C++. This enables the
2547 user to inspect variables from imported namespaces. Support for
2548 namepace aliasing has also been added. So, if a namespace is
2549 aliased in the current scope (e.g. namepace C=A; ) the user can
2550 print variables using the alias (e.g. (gdb) print C::x).
2554 All known bugs relating to the printing of virtual base class were
2555 fixed. It is now possible to call overloaded static methods using a
2560 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2561 and reinterpret_cast<> are now handled by the C++ expression parser.
2565 Xilinx MicroBlaze microblaze-*-*
2570 Xilinx MicroBlaze microblaze
2573 * Multi-program debugging.
2575 GDB now has support for multi-program (a.k.a. multi-executable or
2576 multi-exec) debugging. This allows for debugging multiple inferiors
2577 simultaneously each running a different program under the same GDB
2578 session. See "Debugging Multiple Inferiors and Programs" in the
2579 manual for more information. This implied some user visible changes
2580 in the multi-inferior support. For example, "info inferiors" now
2581 lists inferiors that are not running yet or that have exited
2582 already. See also "New commands" and "New options" below.
2584 * New tracing features
2586 GDB's tracepoint facility now includes several new features:
2588 ** Trace state variables
2590 GDB tracepoints now include support for trace state variables, which
2591 are variables managed by the target agent during a tracing
2592 experiment. They are useful for tracepoints that trigger each
2593 other, so for instance one tracepoint can count hits in a variable,
2594 and then a second tracepoint has a condition that is true when the
2595 count reaches a particular value. Trace state variables share the
2596 $-syntax of GDB convenience variables, and can appear in both
2597 tracepoint actions and condition expressions. Use the "tvariable"
2598 command to create, and "info tvariables" to view; see "Trace State
2599 Variables" in the manual for more detail.
2603 GDB now includes an option for defining fast tracepoints, which
2604 targets may implement more efficiently, such as by installing a jump
2605 into the target agent rather than a trap instruction. The resulting
2606 speedup can be by two orders of magnitude or more, although the
2607 tradeoff is that some program locations on some target architectures
2608 might not allow fast tracepoint installation, for instance if the
2609 instruction to be replaced is shorter than the jump. To request a
2610 fast tracepoint, use the "ftrace" command, with syntax identical to
2611 the regular trace command.
2613 ** Disconnected tracing
2615 It is now possible to detach GDB from the target while it is running
2616 a trace experiment, then reconnect later to see how the experiment
2617 is going. In addition, a new variable disconnected-tracing lets you
2618 tell the target agent whether to continue running a trace if the
2619 connection is lost unexpectedly.
2623 GDB now has the ability to save the trace buffer into a file, and
2624 then use that file as a target, similarly to you can do with
2625 corefiles. You can select trace frames, print data that was
2626 collected in them, and use tstatus to display the state of the
2627 tracing run at the moment that it was saved. To create a trace
2628 file, use "tsave <filename>", and to use it, do "target tfile
2631 ** Circular trace buffer
2633 You can ask the target agent to handle the trace buffer as a
2634 circular buffer, discarding the oldest trace frames to make room for
2635 newer ones, by setting circular-trace-buffer to on. This feature may
2636 not be available for all target agents.
2641 The disassemble command, when invoked with two arguments, now requires
2642 the arguments to be comma-separated.
2645 The info variables command now displays variable definitions. Files
2646 which only declare a variable are not shown.
2649 The source command is now capable of sourcing Python scripts.
2650 This feature is dependent on the debugger being build with Python
2653 Related to this enhancement is also the introduction of a new command
2654 "set script-extension" (see below).
2656 * New commands (for set/show, see "New options" below)
2658 record save [<FILENAME>]
2659 Save a file (in core file format) containing the process record
2660 execution log for replay debugging at a later time.
2662 record restore <FILENAME>
2663 Restore the process record execution log that was saved at an
2664 earlier time, for replay debugging.
2666 add-inferior [-copies <N>] [-exec <FILENAME>]
2669 clone-inferior [-copies <N>] [ID]
2670 Make a new inferior ready to execute the same program another
2671 inferior has loaded.
2676 maint info program-spaces
2677 List the program spaces loaded into GDB.
2679 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2680 show remote interrupt-sequence
2681 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2682 as the sequence to the remote target in order to interrupt the execution.
2683 Ctrl-C is a default. Some system prefers BREAK which is high level of
2684 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2685 Magic SysRq g. It is BREAK signal and character 'g'.
2687 set remote interrupt-on-connect [on | off]
2688 show remote interrupt-on-connect
2689 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2690 remote target when gdb connects to it. This is needed when you debug
2693 set remotebreak [on | off]
2695 Deprecated. Use "set/show remote interrupt-sequence" instead.
2697 tvariable $NAME [ = EXP ]
2698 Create or modify a trace state variable.
2701 List trace state variables and their values.
2703 delete tvariable $NAME ...
2704 Delete one or more trace state variables.
2707 Evaluate the given expressions without collecting anything into the
2708 trace buffer. (Valid in tracepoint actions only.)
2710 ftrace FN / FILE:LINE / *ADDR
2711 Define a fast tracepoint at the given function, line, or address.
2713 * New expression syntax
2715 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2716 GDB now parses 0b101010 identically with 42.
2720 set follow-exec-mode new|same
2721 show follow-exec-mode
2722 Control whether GDB reuses the same inferior across an exec call or
2723 creates a new one. This is useful to be able to restart the old
2724 executable after the inferior having done an exec call.
2726 set default-collect EXPR, ...
2727 show default-collect
2728 Define a list of expressions to be collected at each tracepoint.
2729 This is a useful way to ensure essential items are not overlooked,
2730 such as registers or a critical global variable.
2732 set disconnected-tracing
2733 show disconnected-tracing
2734 If set to 1, the target is instructed to continue tracing if it
2735 loses its connection to GDB. If 0, the target is to stop tracing
2738 set circular-trace-buffer
2739 show circular-trace-buffer
2740 If set to on, the target is instructed to use a circular trace buffer
2741 and discard the oldest trace frames instead of stopping the trace due
2742 to a full trace buffer. If set to off, the trace stops when the buffer
2743 fills up. Some targets may not support this.
2745 set script-extension off|soft|strict
2746 show script-extension
2747 If set to "off", the debugger does not perform any script language
2748 recognition, and all sourced files are assumed to be GDB scripts.
2749 If set to "soft" (the default), files are sourced according to
2750 filename extension, falling back to GDB scripts if the first
2752 If set to "strict", files are sourced according to filename extension.
2754 set ada trust-PAD-over-XVS on|off
2755 show ada trust-PAD-over-XVS
2756 If off, activate a workaround against a bug in the debugging information
2757 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2758 the GCC sources for more information about the GNAT encoding and
2759 PAD types in particular). It is always safe to set this option to
2760 off, but this introduces a slight performance penalty. The default
2763 * Python API Improvements
2765 ** GDB provides the new class gdb.LazyString. This is useful in
2766 some pretty-printing cases. The new method gdb.Value.lazy_string
2767 provides a simple way to create objects of this type.
2769 ** The fields returned by gdb.Type.fields now have an
2770 `is_base_class' attribute.
2772 ** The new method gdb.Type.range returns the range of an array type.
2774 ** The new method gdb.parse_and_eval can be used to parse and
2775 evaluate an expression.
2777 * New remote packets
2780 Define a trace state variable.
2783 Get the current value of a trace state variable.
2786 Set desired tracing behavior upon disconnection.
2789 Set the trace buffer to be linear or circular.
2792 Get data about the tracepoints currently in use.
2796 Process record now works correctly with hardware watchpoints.
2798 Multiple bug fixes have been made to the mips-irix port, making it
2799 much more reliable. In particular:
2800 - Debugging threaded applications is now possible again. Previously,
2801 GDB would hang while starting the program, or while waiting for
2802 the program to stop at a breakpoint.
2803 - Attaching to a running process no longer hangs.
2804 - An error occurring while loading a core file has been fixed.
2805 - Changing the value of the PC register now works again. This fixes
2806 problems observed when using the "jump" command, or when calling
2807 a function from GDB, or even when assigning a new value to $pc.
2808 - With the "finish" and "return" commands, the return value for functions
2809 returning a small array is now correctly printed.
2810 - It is now possible to break on shared library code which gets executed
2811 during a shared library init phase (code executed while executing
2812 their .init section). Previously, the breakpoint would have no effect.
2813 - GDB is now able to backtrace through the signal handler for
2814 non-threaded programs.
2816 PIE (Position Independent Executable) programs debugging is now supported.
2817 This includes debugging execution of PIC (Position Independent Code) shared
2818 libraries although for that, it should be possible to run such libraries as an
2821 *** Changes in GDB 7.0
2823 * GDB now has an interface for JIT compilation. Applications that
2824 dynamically generate code can create symbol files in memory and register
2825 them with GDB. For users, the feature should work transparently, and
2826 for JIT developers, the interface is documented in the GDB manual in the
2827 "JIT Compilation Interface" chapter.
2829 * Tracepoints may now be conditional. The syntax is as for
2830 breakpoints; either an "if" clause appended to the "trace" command,
2831 or the "condition" command is available. GDB sends the condition to
2832 the target for evaluation using the same bytecode format as is used
2833 for tracepoint actions.
2835 * The disassemble command now supports: an optional /r modifier, print the
2836 raw instructions in hex as well as in symbolic form, and an optional /m
2837 modifier to print mixed source+assembly.
2839 * Process record and replay
2841 In a architecture environment that supports ``process record and
2842 replay'', ``process record and replay'' target can record a log of
2843 the process execution, and replay it with both forward and reverse
2846 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2847 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2848 set execution-direction {forward|reverse}, for targets that support
2851 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2852 feature is available with a native GDB running on kernel version
2855 * GDB now has support for multi-byte and wide character sets on the
2856 target. Strings whose character type is wchar_t, char16_t, or
2857 char32_t are now correctly printed. GDB supports wide- and unicode-
2858 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2859 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2860 `printf'. This feature requires iconv to work properly; if your
2861 system does not have a working iconv, GDB can use GNU libiconv. See
2862 the installation instructions for more information.
2864 * GDB now supports automatic retrieval of shared library files from
2865 remote targets. To use this feature, specify a system root that begins
2866 with the `remote:' prefix, either via the `set sysroot' command or via
2867 the `--with-sysroot' configure-time option.
2869 * "info sharedlibrary" now takes an optional regex of libraries to show,
2870 and it now reports if a shared library has no debugging information.
2872 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2873 now complete on file names.
2875 * When completing in expressions, gdb will attempt to limit
2876 completions to allowable structure or union fields, where appropriate.
2877 For instance, consider:
2879 # struct example { int f1; double f2; };
2880 # struct example variable;
2883 If the user types TAB at the end of this command line, the available
2884 completions will be "f1" and "f2".
2886 * Inlined functions are now supported. They show up in backtraces, and
2887 the "step", "next", and "finish" commands handle them automatically.
2889 * GDB now supports the token-splicing (##) and stringification (#)
2890 operators when expanding macros. It also supports variable-arity
2893 * GDB now supports inspecting extra signal information, exported by
2894 the new $_siginfo convenience variable. The feature is currently
2895 implemented on linux ARM, i386 and amd64.
2897 * GDB can now display the VFP floating point registers and NEON vector
2898 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2899 can provide these registers (requires Linux 2.6.30 or later). Remote
2900 and simulator targets may also provide them.
2902 * New remote packets
2905 Search memory for a sequence of bytes.
2908 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2909 operation over reliable transport links. Use of this packet is
2910 controlled by the `set remote noack-packet' command.
2913 Kill the process with the specified process ID. Use this in preference
2914 to `k' when multiprocess protocol extensions are supported.
2917 Obtains additional operating system information
2921 Read or write additional signal information.
2923 * Removed remote protocol undocumented extension
2925 An undocumented extension to the remote protocol's `S' stop reply
2926 packet that permited the stub to pass a process id was removed.
2927 Remote servers should use the `T' stop reply packet instead.
2929 * GDB now supports multiple function calling conventions according to the
2930 DWARF-2 DW_AT_calling_convention function attribute.
2932 * The SH target utilizes the aforementioned change to distinguish between gcc
2933 and Renesas calling convention. It also adds the new CLI commands
2934 `set/show sh calling-convention'.
2936 * GDB can now read compressed debug sections, as produced by GNU gold
2937 with the --compress-debug-sections=zlib flag.
2939 * 64-bit core files are now supported on AIX.
2941 * Thread switching is now supported on Tru64.
2943 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2944 which will be allocated using malloc later in program execution.
2946 * The qXfer:libraries:read remote procotol packet now allows passing a
2947 list of section offsets.
2949 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2950 conditions handling signals delivered during attach or thread creation
2951 have also been fixed.
2953 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2954 From the user's standpoint, all unqualified instances of True and False
2955 are treated as the standard definitions, regardless of context.
2957 * GDB now parses C++ symbol and type names more flexibly. For
2960 template<typename T> class C { };
2963 GDB will now correctly handle all of:
2965 ptype C<char const *>
2966 ptype C<char const*>
2967 ptype C<const char *>
2968 ptype C<const char*>
2970 * New features in the GDB remote stub, gdbserver
2972 - The "--wrapper" command-line argument tells gdbserver to use a
2973 wrapper program to launch programs for debugging.
2975 - On PowerPC and S/390 targets, it is now possible to use a single
2976 gdbserver executable to debug both 32-bit and 64-bit programs.
2977 (This requires gdbserver itself to be built as a 64-bit executable.)
2979 - gdbserver uses the new noack protocol mode for TCP connections to
2980 reduce communications latency, if also supported and enabled in GDB.
2982 - Support for the sparc64-linux-gnu target is now included in
2985 - The amd64-linux build of gdbserver now supports debugging both
2986 32-bit and 64-bit programs.
2988 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2989 now support hardware watchpoints, and will use them automatically
2994 GDB now has support for scripting using Python. Whether this is
2995 available is determined at configure time.
2997 New GDB commands can now be written in Python.
2999 * Ada tasking support
3001 Ada tasks can now be inspected in GDB. The following commands have
3005 Print the list of Ada tasks.
3007 Print detailed information about task number N.
3009 Print the task number of the current task.
3011 Switch the context of debugging to task number N.
3013 * Support for user-defined prefixed commands. The "define" command can
3014 add new commands to existing prefixes, e.g. "target".
3016 * Multi-inferior, multi-process debugging.
3018 GDB now has generalized support for multi-inferior debugging. See
3019 "Debugging Multiple Inferiors" in the manual for more information.
3020 Although availability still depends on target support, the command
3021 set is more uniform now. The GNU/Linux specific multi-forks support
3022 has been migrated to this new framework. This implied some user
3023 visible changes; see "New commands" and also "Removed commands"
3026 * Target descriptions can now describe the target OS ABI. See the
3027 "Target Description Format" section in the user manual for more
3030 * Target descriptions can now describe "compatible" architectures
3031 to indicate that the target can execute applications for a different
3032 architecture in addition to those for the main target architecture.
3033 See the "Target Description Format" section in the user manual for
3036 * Multi-architecture debugging.
3038 GDB now includes general supports for debugging applications on
3039 hybrid systems that use more than one single processor architecture
3040 at the same time. Each such hybrid architecture still requires
3041 specific support to be added. The only hybrid architecture supported
3042 in this version of GDB is the Cell Broadband Engine.
3044 * GDB now supports integrated debugging of Cell/B.E. applications that
3045 use both the PPU and SPU architectures. To enable support for hybrid
3046 Cell/B.E. debugging, you need to configure GDB to support both the
3047 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3048 --enable-targets configure option.
3050 * Non-stop mode debugging.
3052 For some targets, GDB now supports an optional mode of operation in
3053 which you can examine stopped threads while other threads continue
3054 to execute freely. This is referred to as non-stop mode, with the
3055 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3056 section in the user manual for more information.
3058 To be able to support remote non-stop debugging, a remote stub needs
3059 to implement the non-stop mode remote protocol extensions, as
3060 described in the "Remote Non-Stop" section of the user manual. The
3061 GDB remote stub, gdbserver, has been adjusted to support these
3062 extensions on linux targets.
3064 * New commands (for set/show, see "New options" below)
3066 catch syscall [NAME(S) | NUMBER(S)]
3067 Catch system calls. Arguments, which should be names of system
3068 calls or their numbers, mean catch only those syscalls. Without
3069 arguments, every syscall will be caught. When the inferior issues
3070 any of the specified syscalls, GDB will stop and announce the system
3071 call, both when it is called and when its call returns. This
3072 feature is currently available with a native GDB running on the
3073 Linux Kernel, under the following architectures: x86, x86_64,
3074 PowerPC and PowerPC64.
3076 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3078 Search memory for a sequence of bytes.
3080 maint set python print-stack
3081 maint show python print-stack
3082 Show a stack trace when an error is encountered in a Python script.
3085 Invoke CODE by passing it to the Python interpreter.
3090 These allow macros to be defined, undefined, and listed
3094 Show operating system information about processes.
3097 List the inferiors currently under GDB's control.
3100 Switch focus to inferior number NUM.
3103 Detach from inferior number NUM.
3106 Kill inferior number NUM.
3110 set spu stop-on-load
3111 show spu stop-on-load
3112 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3114 set spu auto-flush-cache
3115 show spu auto-flush-cache
3116 Control whether to automatically flush the software-managed cache
3117 during Cell/B.E. debugging.
3119 set sh calling-convention
3120 show sh calling-convention
3121 Control the calling convention used when calling SH target functions.
3124 show debug timestamp
3125 Control display of timestamps with GDB debugging output.
3127 set disassemble-next-line
3128 show disassemble-next-line
3129 Control display of disassembled source lines or instructions when
3132 set remote noack-packet
3133 show remote noack-packet
3134 Set/show the use of remote protocol QStartNoAckMode packet. See above
3135 under "New remote packets."
3137 set remote query-attached-packet
3138 show remote query-attached-packet
3139 Control use of remote protocol `qAttached' (query-attached) packet.
3141 set remote read-siginfo-object
3142 show remote read-siginfo-object
3143 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3146 set remote write-siginfo-object
3147 show remote write-siginfo-object
3148 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3151 set remote reverse-continue
3152 show remote reverse-continue
3153 Control use of remote protocol 'bc' (reverse-continue) packet.
3155 set remote reverse-step
3156 show remote reverse-step
3157 Control use of remote protocol 'bs' (reverse-step) packet.
3159 set displaced-stepping
3160 show displaced-stepping
3161 Control displaced stepping mode. Displaced stepping is a way to
3162 single-step over breakpoints without removing them from the debuggee.
3163 Also known as "out-of-line single-stepping".
3166 show debug displaced
3167 Control display of debugging info for displaced stepping.
3169 maint set internal-error
3170 maint show internal-error
3171 Control what GDB does when an internal error is detected.
3173 maint set internal-warning
3174 maint show internal-warning
3175 Control what GDB does when an internal warning is detected.
3180 Use a wrapper program to launch programs for debugging.
3182 set multiple-symbols (all|ask|cancel)
3183 show multiple-symbols
3184 The value of this variable can be changed to adjust the debugger behavior
3185 when an expression or a breakpoint location contains an ambiguous symbol
3186 name (an overloaded function name, for instance).
3188 set breakpoint always-inserted
3189 show breakpoint always-inserted
3190 Keep breakpoints always inserted in the target, as opposed to inserting
3191 them when resuming the target, and removing them when the target stops.
3192 This option can improve debugger performance on slow remote targets.
3194 set arm fallback-mode (arm|thumb|auto)
3195 show arm fallback-mode
3196 set arm force-mode (arm|thumb|auto)
3198 These commands control how ARM GDB determines whether instructions
3199 are ARM or Thumb. The default for both settings is auto, which uses
3200 the current CPSR value for instructions without symbols; previous
3201 versions of GDB behaved as if "set arm fallback-mode arm".
3203 set disable-randomization
3204 show disable-randomization
3205 Standalone programs run with the virtual address space randomization enabled
3206 by default on some platforms. This option keeps the addresses stable across
3207 multiple debugging sessions.
3211 Control whether other threads are stopped or not when some thread hits
3216 Requests that asynchronous execution is enabled in the target, if available.
3217 In this case, it's possible to resume target in the background, and interact
3218 with GDB while the target is running. "show target-async" displays the
3219 current state of asynchronous execution of the target.
3221 set target-wide-charset
3222 show target-wide-charset
3223 The target-wide-charset is the name of the character set that GDB
3224 uses when printing characters whose type is wchar_t.
3226 set tcp auto-retry (on|off)
3228 set tcp connect-timeout
3229 show tcp connect-timeout
3230 These commands allow GDB to retry failed TCP connections to a remote stub
3231 with a specified timeout period; this is useful if the stub is launched
3232 in parallel with GDB but may not be ready to accept connections immediately.
3234 set libthread-db-search-path
3235 show libthread-db-search-path
3236 Control list of directories which GDB will search for appropriate
3239 set schedule-multiple (on|off)
3240 show schedule-multiple
3241 Allow GDB to resume all threads of all processes or only threads of
3242 the current process.
3246 Use more aggressive caching for accesses to the stack. This improves
3247 performance of remote debugging (particularly backtraces) without
3248 affecting correctness.
3250 set interactive-mode (on|off|auto)
3251 show interactive-mode
3252 Control whether GDB runs in interactive mode (on) or not (off).
3253 When in interactive mode, GDB waits for the user to answer all
3254 queries. Otherwise, GDB does not wait and assumes the default
3255 answer. When set to auto (the default), GDB determines which
3256 mode to use based on the stdin settings.
3261 For program forks, this is replaced by the new more generic `info
3262 inferiors' command. To list checkpoints, you can still use the
3263 `info checkpoints' command, which was an alias for the `info forks'
3267 Replaced by the new `inferior' command. To switch between
3268 checkpoints, you can still use the `restart' command, which was an
3269 alias for the `fork' command.
3272 This is removed, since some targets don't have a notion of
3273 processes. To switch between processes, you can still use the
3274 `inferior' command using GDB's own inferior number.
3277 For program forks, this is replaced by the new more generic `kill
3278 inferior' command. To delete a checkpoint, you can still use the
3279 `delete checkpoint' command, which was an alias for the `delete
3283 For program forks, this is replaced by the new more generic `detach
3284 inferior' command. To detach a checkpoint, you can still use the
3285 `detach checkpoint' command, which was an alias for the `detach
3288 * New native configurations
3290 x86/x86_64 Darwin i[34567]86-*-darwin*
3292 x86_64 MinGW x86_64-*-mingw*
3296 Lattice Mico32 lm32-*
3297 x86 DICOS i[34567]86-*-dicos*
3298 x86_64 DICOS x86_64-*-dicos*
3301 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3302 (mingw32ce) debugging.
3308 These commands were actually not implemented on any target.
3310 *** Changes in GDB 6.8
3312 * New native configurations
3314 NetBSD/hppa hppa*-*netbsd*
3315 Xtensa GNU/Linux xtensa*-*-linux*
3319 NetBSD/hppa hppa*-*-netbsd*
3320 Xtensa GNU/Lunux xtensa*-*-linux*
3322 * Change in command line behavior -- corefiles vs. process ids.
3324 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3325 attaching to process NUMBER fails, GDB no longer attempts to open a
3326 core file named NUMBER. Attaching to a program using the -c option
3327 is no longer supported. Instead, use the '-p' or '--pid' options.
3329 * GDB can now be built as a native debugger for debugging Windows x86
3330 (mingw32) Portable Executable (PE) programs.
3332 * Pending breakpoints no longer change their number when their address
3335 * GDB now supports breakpoints with multiple locations,
3336 including breakpoints on C++ constructors, inside C++ templates,
3337 and in inlined functions.
3339 * GDB's ability to debug optimized code has been improved. GDB more
3340 accurately identifies function bodies and lexical blocks that occupy
3341 more than one contiguous range of addresses.
3343 * Target descriptions can now describe registers for PowerPC.
3345 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3346 registers on PowerPC targets.
3348 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3349 targets even when the libthread_db library is not available.
3351 * The GDB remote stub, gdbserver, now supports the new file transfer
3352 commands (remote put, remote get, and remote delete).
3354 * The GDB remote stub, gdbserver, now supports run and attach in
3355 extended-remote mode.
3357 * hppa*64*-*-hpux11* target broken
3358 The debugger is unable to start a program and fails with the following
3359 error: "Error trying to get information about dynamic linker".
3360 The gdb-6.7 release is also affected.
3362 * GDB now supports the --enable-targets= configure option to allow
3363 building a single GDB executable that supports multiple remote
3364 target architectures.
3366 * GDB now supports debugging C and C++ programs which use the
3367 Decimal Floating Point extension. In addition, the PowerPC target
3368 now has a set of pseudo-registers to inspect decimal float values
3369 stored in two consecutive float registers.
3371 * The -break-insert MI command can optionally create pending
3374 * Improved support for debugging Ada
3375 Many improvements to the Ada language support have been made. These
3377 - Better support for Ada2005 interface types
3378 - Improved handling of arrays and slices in general
3379 - Better support for Taft-amendment types
3380 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3382 - Improved command completion in Ada
3385 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3390 set print frame-arguments (all|scalars|none)
3391 show print frame-arguments
3392 The value of this variable can be changed to control which argument
3393 values should be printed by the debugger when displaying a frame.
3398 Transfer files to and from a remote target, and delete remote files.
3405 Transfer files to and from a remote target, and delete remote files.
3407 * New remote packets
3414 Open, close, read, write, and delete files on the remote system.
3417 Attach to an existing process on the remote system, in extended-remote
3421 Run a new process on the remote system, in extended-remote mode.
3423 *** Changes in GDB 6.7
3425 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3426 bfd, libiberty and opcodes, as revealed by static analysis donated by
3427 Coverity, Inc. (http://scan.coverity.com).
3429 * When looking up multiply-defined global symbols, GDB will now prefer the
3430 symbol definition in the current shared library if it was built using the
3431 -Bsymbolic linker option.
3433 * When the Text User Interface (TUI) is not configured, GDB will now
3434 recognize the -tui command-line option and print a message that the TUI
3437 * The GDB remote stub, gdbserver, now has lower overhead for high
3438 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3440 * GDB for MIPS targets now autodetects whether a remote target provides
3441 32-bit or 64-bit register values.
3443 * Support for C++ member pointers has been improved.
3445 * GDB now understands XML target descriptions, which specify the
3446 target's overall architecture. GDB can read a description from
3447 a local file or over the remote serial protocol.
3449 * Vectors of single-byte data use a new integer type which is not
3450 automatically displayed as character or string data.
3452 * The /s format now works with the print command. It displays
3453 arrays of single-byte integers and pointers to single-byte integers
3456 * Target descriptions can now describe target-specific registers,
3457 for architectures which have implemented the support (currently
3458 only ARM, M68K, and MIPS).
3460 * GDB and the GDB remote stub, gdbserver, now support the XScale
3463 * The GDB remote stub, gdbserver, has been updated to support
3464 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3465 has been rewritten to use the standard GDB remote protocol.
3467 * GDB can now step into C++ functions which are called through thunks.
3469 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3471 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3472 layout. It also supports a TextSeg= and DataSeg= response when only
3473 segment base addresses (rather than offsets) are available.
3475 * The /i format now outputs any trailing branch delay slot instructions
3476 immediately following the last instruction within the count specified.
3478 * The GDB remote protocol "T" stop reply packet now supports a
3479 "library" response. Combined with the new "qXfer:libraries:read"
3480 packet, this response allows GDB to debug shared libraries on targets
3481 where the operating system manages the list of loaded libraries (e.g.
3482 Windows and SymbianOS).
3484 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3485 (DLLs) on Windows and Windows CE targets.
3487 * GDB now supports a faster verification that a .debug file matches its binary
3488 according to its build-id signature, if the signature is present.
3494 Enable or disable hardware flow control (RTS/CTS) on the serial port
3495 when debugging using remote targets.
3497 set mem inaccessible-by-default
3498 show mem inaccessible-by-default
3499 If the target supplies a memory map, for instance via the remote
3500 protocol's "qXfer:memory-map:read" packet, setting this variable
3501 prevents GDB from accessing memory outside the memory map. This
3502 is useful for targets with memory mapped registers or which react
3503 badly to accesses of unmapped address space.
3505 set breakpoint auto-hw
3506 show breakpoint auto-hw
3507 If the target supplies a memory map, for instance via the remote
3508 protocol's "qXfer:memory-map:read" packet, setting this variable
3509 lets GDB use hardware breakpoints automatically for memory regions
3510 where it can not use software breakpoints. This covers both the
3511 "break" command and internal breakpoints used for other commands
3512 including "next" and "finish".
3515 catch exception unhandled
3516 Stop the program execution when Ada exceptions are raised.
3519 Stop the program execution when an Ada assertion failed.
3523 Set an alternate system root for target files. This is a more
3524 general version of "set solib-absolute-prefix", which is now
3525 an alias to "set sysroot".
3528 Provide extended SPU facility status information. This set of
3529 commands is available only when debugging the Cell/B.E. SPU
3532 * New native configurations
3534 OpenBSD/sh sh*-*openbsd*
3537 unset tdesc filename
3539 Use the specified local file as an XML target description, and do
3540 not query the target for its built-in description.
3544 OpenBSD/sh sh*-*-openbsd*
3545 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3546 Toshiba Media Processor mep-elf
3548 * New remote packets
3551 Ignore the specified signals; pass them directly to the debugged program
3552 without stopping other threads or reporting them to GDB.
3554 qXfer:features:read:
3555 Read an XML target description from the target, which describes its
3560 Read or write contents of an spufs file on the target system. These
3561 packets are available only on the Cell/B.E. SPU architecture.
3563 qXfer:libraries:read:
3564 Report the loaded shared libraries. Combined with new "T" packet
3565 response, this packet allows GDB to debug shared libraries on
3566 targets where the operating system manages the list of loaded
3567 libraries (e.g. Windows and SymbianOS).
3571 Support for these obsolete configurations has been removed.
3579 i[34567]86-*-lynxos*
3580 i[34567]86-*-netware*
3581 i[34567]86-*-sco3.2v5*
3582 i[34567]86-*-sco3.2v4*
3584 i[34567]86-*-sysv4.2*
3587 i[34567]86-*-unixware2*
3588 i[34567]86-*-unixware*
3597 * Other removed features
3604 Various m68k-only ROM monitors.
3611 Various Renesas ROM monitors and debugging interfaces for SH and
3616 Support for a Macraigor serial interface to on-chip debugging.
3617 GDB does not directly support the newer parallel or USB
3622 A debug information format. The predecessor to DWARF 2 and
3623 DWARF 3, which are still supported.
3625 Support for the HP aCC compiler on HP-UX/PA-RISC
3627 SOM-encapsulated symbolic debugging information, automatic
3628 invocation of pxdb, and the aCC custom C++ ABI. This does not
3629 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3630 with aCC can still be debugged on an assembly level.
3632 MIPS ".pdr" sections
3634 A MIPS-specific format used to describe stack frame layout
3635 in debugging information.
3639 GDB could work with an older version of Guile to debug
3640 the interpreter and Scheme programs running in it.
3642 set mips stack-arg-size
3643 set mips saved-gpreg-size
3645 Use "set mips abi" to control parameter passing for MIPS.
3647 *** Changes in GDB 6.6
3652 Cell Broadband Engine SPU spu-elf
3654 * GDB can now be configured as a cross-debugger targeting native Windows
3655 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3656 running on a Windows system over TCP/IP to debug Windows programs.
3658 * The GDB remote stub, gdbserver, has been updated to support Windows and
3659 Cygwin debugging. Both single-threaded and multi-threaded programs are
3662 * The "set trust-readonly-sections" command works again. This command was
3663 broken in GDB 6.3, 6.4, and 6.5.
3665 * The "load" command now supports writing to flash memory, if the remote
3666 stub provides the required support.
3668 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3669 longer requires symbolic debug information (e.g. DWARF-2).
3674 unset substitute-path
3675 show substitute-path
3676 Manage a list of substitution rules that GDB uses to rewrite the name
3677 of the directories where the sources are located. This can be useful
3678 for instance when the sources were moved to a different location
3679 between compilation and debugging.
3683 Print each CLI command as it is executed. Each command is prefixed with
3684 a number of `+' symbols representing the nesting depth.
3685 The source command now has a `-v' option to enable the same feature.
3689 The ARM Demon monitor support (RDP protocol, "target rdp").
3691 Kernel Object Display, an embedded debugging feature which only worked with
3692 an obsolete version of Cisco IOS.
3694 The 'set download-write-size' and 'show download-write-size' commands.
3696 * New remote packets
3699 Tell a stub about GDB client features, and request remote target features.
3700 The first feature implemented is PacketSize, which allows the target to
3701 specify the size of packets it can handle - to minimize the number of
3702 packets required and improve performance when connected to a remote
3706 Fetch an OS auxilliary vector from the remote stub. This packet is a
3707 more efficient replacement for qPart:auxv:read.
3709 qXfer:memory-map:read:
3710 Fetch a memory map from the remote stub, including information about
3711 RAM, ROM, and flash memory devices.
3716 Erase and program a flash memory device.
3718 * Removed remote packets
3721 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3722 used it, and only gdbserver implemented it.
3724 *** Changes in GDB 6.5
3728 Renesas M32C/M16C m32c-elf
3730 Morpho Technologies ms1 ms1-elf
3734 init-if-undefined Initialize a convenience variable, but
3735 only if it doesn't already have a value.
3737 The following commands are presently only implemented for native GNU/Linux:
3739 checkpoint Save a snapshot of the program state.
3741 restart <n> Return the program state to a
3742 previously saved state.
3744 info checkpoints List currently saved checkpoints.
3746 delete-checkpoint <n> Delete a previously saved checkpoint.
3748 set|show detach-on-fork Tell gdb whether to detach from a newly
3749 forked process, or to keep debugging it.
3751 info forks List forks of the user program that
3752 are available to be debugged.
3754 fork <n> Switch to debugging one of several
3755 forks of the user program that are
3756 available to be debugged.
3758 delete-fork <n> Delete a fork from the list of forks
3759 that are available to be debugged (and
3760 kill the forked process).
3762 detach-fork <n> Delete a fork from the list of forks
3763 that are available to be debugged (and
3764 allow the process to continue).
3768 Morpho Technologies ms2 ms1-elf
3770 * Improved Windows host support
3772 GDB now builds as a cross debugger hosted on i686-mingw32, including
3773 native console support, and remote communications using either
3774 network sockets or serial ports.
3776 * Improved Modula-2 language support
3778 GDB can now print most types in the Modula-2 syntax. This includes:
3779 basic types, set types, record types, enumerated types, range types,
3780 pointer types and ARRAY types. Procedure var parameters are correctly
3781 printed and hexadecimal addresses and character constants are also
3782 written in the Modula-2 syntax. Best results can be obtained by using
3783 GNU Modula-2 together with the -gdwarf-2 command line option.
3787 The ARM rdi-share module.
3789 The Netware NLM debug server.
3791 *** Changes in GDB 6.4
3793 * New native configurations
3795 OpenBSD/arm arm*-*-openbsd*
3796 OpenBSD/mips64 mips64-*-openbsd*
3800 Morpho Technologies ms1 ms1-elf
3802 * New command line options
3804 --batch-silent As for --batch, but totally silent.
3805 --return-child-result The debugger will exist with the same value
3806 the child (debugged) program exited with.
3807 --eval-command COMMAND, -ex COMMAND
3808 Execute a single GDB CLI command. This may be
3809 specified multiple times and in conjunction
3810 with the --command (-x) option.
3812 * Deprecated commands removed
3814 The following commands, that were deprecated in 2000, have been
3818 set|show arm disassembly-flavor set|show arm disassembler
3819 othernames set arm disassembler
3820 set|show remotedebug set|show debug remote
3821 set|show archdebug set|show debug arch
3822 set|show eventdebug set|show debug event
3825 * New BSD user-level threads support
3827 It is now possible to debug programs using the user-level threads
3828 library on OpenBSD and FreeBSD. Currently supported (target)
3831 FreeBSD/amd64 x86_64-*-freebsd*
3832 FreeBSD/i386 i386-*-freebsd*
3833 OpenBSD/i386 i386-*-openbsd*
3835 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3836 are not yet supported.
3838 * New support for Matsushita MN10300 w/sim added
3839 (Work in progress). mn10300-elf.
3841 * REMOVED configurations and files
3843 VxWorks and the XDR protocol *-*-vxworks
3844 Motorola MCORE mcore-*-*
3845 National Semiconductor NS32000 ns32k-*-*
3847 * New "set print array-indexes" command
3849 After turning this setting "on", GDB prints the index of each element
3850 when displaying arrays. The default is "off" to preserve the previous
3853 * VAX floating point support
3855 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3857 * User-defined command support
3859 In addition to using $arg0..$arg9 for argument passing, it is now possible
3860 to use $argc to determine now many arguments have been passed. See the
3861 section on user-defined commands in the user manual for more information.
3863 *** Changes in GDB 6.3:
3865 * New command line option
3867 GDB now accepts -l followed by a number to set the timeout for remote
3870 * GDB works with GCC -feliminate-dwarf2-dups
3872 GDB now supports a more compact representation of DWARF-2 debug
3873 information using DW_FORM_ref_addr references. These are produced
3874 by GCC with the option -feliminate-dwarf2-dups and also by some
3875 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3876 to use -feliminate-dwarf2-dups.
3878 * Internationalization
3880 When supported by the host system, GDB will be built with
3881 internationalization (libintl). The task of marking up the sources is
3882 continued, we're looking forward to our first translation.
3886 Initial support for debugging programs compiled with the GNAT
3887 implementation of the Ada programming language has been integrated
3888 into GDB. In this release, support is limited to expression evaluation.
3890 * New native configurations
3892 GNU/Linux/m32r m32r-*-linux-gnu
3896 GDB's remote protocol now includes support for the 'p' packet. This
3897 packet is used to fetch individual registers from a remote inferior.
3899 * END-OF-LIFE registers[] compatibility module
3901 GDB's internal register infrastructure has been completely rewritten.
3902 The new infrastructure making possible the implementation of key new
3903 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3906 GDB 6.3 will be the last release to include the the registers[]
3907 compatibility module that allowed out-of-date configurations to
3908 continue to work. This change directly impacts the following
3918 powerpc bdm protocol
3920 Unless there is activity to revive these configurations, they will be
3921 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3923 * OBSOLETE configurations and files
3925 Configurations that have been declared obsolete in this release have
3926 been commented out. Unless there is activity to revive these
3927 configurations, the next release of GDB will have their sources
3928 permanently REMOVED.
3937 *** Changes in GDB 6.2.1:
3939 * MIPS `break main; run' gave an heuristic-fence-post warning
3941 When attempting to run even a simple program, a warning about
3942 heuristic-fence-post being hit would be reported. This problem has
3945 * MIPS IRIX 'long double' crashed GDB
3947 When examining a long double variable, GDB would get a segmentation
3948 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3949 IRIX long double values).
3953 A bug in the VAX stack code was causing problems with the "next"
3954 command. This problem has been fixed.
3956 *** Changes in GDB 6.2:
3958 * Fix for ``many threads''
3960 On GNU/Linux systems that use the NPTL threads library, a program
3961 rapidly creating and deleting threads would confuse GDB leading to the
3964 ptrace: No such process.
3965 thread_db_get_info: cannot get thread info: generic error
3967 This problem has been fixed.
3969 * "-async" and "-noasync" options removed.
3971 Support for the broken "-noasync" option has been removed (it caused
3974 * New ``start'' command.
3976 This command runs the program until the begining of the main procedure.
3978 * New BSD Kernel Data Access Library (libkvm) interface
3980 Using ``target kvm'' it is now possible to debug kernel core dumps and
3981 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3982 platforms. Currently supported (native-only) configurations are:
3984 FreeBSD/amd64 x86_64-*-freebsd*
3985 FreeBSD/i386 i?86-*-freebsd*
3986 NetBSD/i386 i?86-*-netbsd*
3987 NetBSD/m68k m68*-*-netbsd*
3988 NetBSD/sparc sparc-*-netbsd*
3989 OpenBSD/amd64 x86_64-*-openbsd*
3990 OpenBSD/i386 i?86-*-openbsd*
3991 OpenBSD/m68k m68*-openbsd*
3992 OpenBSD/sparc sparc-*-openbsd*
3994 * Signal trampoline code overhauled
3996 Many generic problems with GDB's signal handling code have been fixed.
3997 These include: backtraces through non-contiguous stacks; recognition
3998 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3999 call; backtrace through a signal trampoline; step into and out of
4000 signal handlers; and single-stepping in the signal trampoline.
4002 Please note that kernel bugs are a limiting factor here. These
4003 features have been shown to work on an s390 GNU/Linux system that
4004 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4006 * Cygwin support for DWARF 2 added.
4008 * New native configurations
4010 GNU/Linux/hppa hppa*-*-linux*
4011 OpenBSD/hppa hppa*-*-openbsd*
4012 OpenBSD/m68k m68*-*-openbsd*
4013 OpenBSD/m88k m88*-*-openbsd*
4014 OpenBSD/powerpc powerpc-*-openbsd*
4015 NetBSD/vax vax-*-netbsd*
4016 OpenBSD/vax vax-*-openbsd*
4018 * END-OF-LIFE frame compatibility module
4020 GDB's internal frame infrastructure has been completely rewritten.
4021 The new infrastructure making it possible to support key new features
4022 including DWARF 2 Call Frame Information. To aid in the task of
4023 migrating old configurations to this new infrastructure, a
4024 compatibility module, that allowed old configurations to continue to
4025 work, was also included.
4027 GDB 6.2 will be the last release to include this frame compatibility
4028 module. This change directly impacts the following configurations:
4038 Unless there is activity to revive these configurations, they will be
4039 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4041 * REMOVED configurations and files
4043 Sun 3, running SunOS 3 m68*-*-sunos3*
4044 Sun 3, running SunOS 4 m68*-*-sunos4*
4045 Sun 2, running SunOS 3 m68000-*-sunos3*
4046 Sun 2, running SunOS 4 m68000-*-sunos4*
4047 Motorola 680x0 running LynxOS m68*-*-lynxos*
4048 AT&T 3b1/Unix pc m68*-att-*
4049 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4050 decstation mips-dec-* mips-little-*
4051 riscos mips-*-riscos* mips-*-sysv*
4052 sonymips mips-sony-*
4053 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4055 *** Changes in GDB 6.1.1:
4057 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4059 The TUI (Text-mode User Interface) is now built as part of a default
4060 GDB configuration. It is enabled by either selecting the TUI with the
4061 command line option "-i=tui" or by running the separate "gdbtui"
4062 program. For more information on the TUI, see the manual "Debugging
4065 * Pending breakpoint support (also included in GDB 6.1)
4067 Support has been added to allow you to specify breakpoints in shared
4068 libraries that have not yet been loaded. If a breakpoint location
4069 cannot be found, and the "breakpoint pending" option is set to auto,
4070 GDB queries you if you wish to make the breakpoint pending on a future
4071 shared-library load. If and when GDB resolves the breakpoint symbol,
4072 the pending breakpoint is removed as one or more regular breakpoints
4075 Pending breakpoints are very useful for GCJ Java debugging.
4077 * Fixed ISO-C build problems
4079 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4080 non ISO-C code that stopped them being built using a more strict ISO-C
4081 compiler (e.g., IBM's C compiler).
4083 * Fixed build problem on IRIX 5
4085 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4086 wasn't able to compile compile on an IRIX 5 system.
4088 * Added execute permission to gdb/gdbserver/configure
4090 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4091 permission. This bug would cause configure to fail on a number of
4092 systems (Solaris, IRIX). Ref: server/519.
4094 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4096 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4097 has been updated to use constant array sizes.
4099 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4101 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4102 its generated DWARF Call Frame Info. This encoding was causing GDB to
4103 panic, that panic has been fixed. Ref: gdb/1628.
4105 * Fixed a problem when examining parameters in shared library code.
4107 When examining parameters in optimized shared library code generated
4108 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4109 not available''. GDB now correctly displays the variable's value.
4111 *** Changes in GDB 6.1:
4113 * Removed --with-mmalloc
4115 Support for the mmalloc memory manager has been removed, as it
4116 conflicted with the internal gdb byte cache.
4118 * Changes in AMD64 configurations
4120 The AMD64 target now includes the %cs and %ss registers. As a result
4121 the AMD64 remote protocol has changed; this affects the floating-point
4122 and SSE registers. If you rely on those registers for your debugging,
4123 you should upgrade gdbserver on the remote side.
4125 * Revised SPARC target
4127 The SPARC target has been completely revised, incorporating the
4128 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4129 support for LynxOS and SunOS 4 has been dropped. Calling functions
4130 from within GDB on operating systems with a non-executable stack
4131 (Solaris, OpenBSD) now works.
4135 GDB has a new C++ demangler which does a better job on the mangled
4136 names generated by current versions of g++. It also runs faster, so
4137 with this and other changes gdb should now start faster on large C++
4140 * DWARF 2 Location Expressions
4142 GDB support for location expressions has been extended to support function
4143 arguments and frame bases. Older versions of GDB could crash when they
4146 * C++ nested types and namespaces
4148 GDB's support for nested types and namespaces in C++ has been
4149 improved, especially if you use the DWARF 2 debugging format. (This
4150 is the default for recent versions of GCC on most platforms.)
4151 Specifically, if you have a class "Inner" defined within a class or
4152 namespace "Outer", then GDB realizes that the class's name is
4153 "Outer::Inner", not simply "Inner". This should greatly reduce the
4154 frequency of complaints about not finding RTTI symbols. In addition,
4155 if you are stopped at inside of a function defined within a namespace,
4156 GDB modifies its name lookup accordingly.
4158 * New native configurations
4160 NetBSD/amd64 x86_64-*-netbsd*
4161 OpenBSD/amd64 x86_64-*-openbsd*
4162 OpenBSD/alpha alpha*-*-openbsd*
4163 OpenBSD/sparc sparc-*-openbsd*
4164 OpenBSD/sparc64 sparc64-*-openbsd*
4166 * New debugging protocols
4168 M32R with SDI protocol m32r-*-elf*
4170 * "set prompt-escape-char" command deleted.
4172 The command "set prompt-escape-char" has been deleted. This command,
4173 and its very obscure effet on GDB's prompt, was never documented,
4174 tested, nor mentioned in the NEWS file.
4176 * OBSOLETE configurations and files
4178 Configurations that have been declared obsolete in this release have
4179 been commented out. Unless there is activity to revive these
4180 configurations, the next release of GDB will have their sources
4181 permanently REMOVED.
4183 Sun 3, running SunOS 3 m68*-*-sunos3*
4184 Sun 3, running SunOS 4 m68*-*-sunos4*
4185 Sun 2, running SunOS 3 m68000-*-sunos3*
4186 Sun 2, running SunOS 4 m68000-*-sunos4*
4187 Motorola 680x0 running LynxOS m68*-*-lynxos*
4188 AT&T 3b1/Unix pc m68*-att-*
4189 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4190 decstation mips-dec-* mips-little-*
4191 riscos mips-*-riscos* mips-*-sysv*
4192 sonymips mips-sony-*
4193 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4195 * REMOVED configurations and files
4197 SGI Irix-4.x mips-sgi-irix4 or iris4
4198 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4199 Z8000 simulator z8k-zilog-none or z8ksim
4200 Matsushita MN10200 w/simulator mn10200-*-*
4201 H8/500 simulator h8500-hitachi-hms or h8500hms
4202 HP/PA running BSD hppa*-*-bsd*
4203 HP/PA running OSF/1 hppa*-*-osf*
4204 HP/PA Pro target hppa*-*-pro*
4205 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4206 386BSD i[3456]86-*-bsd*
4207 Sequent family i[3456]86-sequent-sysv4*
4208 i[3456]86-sequent-sysv*
4209 i[3456]86-sequent-bsd*
4210 SPARC running LynxOS sparc-*-lynxos*
4211 SPARC running SunOS 4 sparc-*-sunos4*
4212 Tsqware Sparclet sparclet-*-*
4213 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4215 *** Changes in GDB 6.0:
4219 Support for debugging the Objective-C programming language has been
4220 integrated into GDB.
4222 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4224 DWARF 2's Call Frame Information makes available compiler generated
4225 information that more exactly describes the program's run-time stack.
4226 By using this information, GDB is able to provide more robust stack
4229 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4230 have been updated to use a new backtrace mechanism which includes
4231 DWARF 2 CFI support.
4235 GDB's remote protocol has been extended to include support for hosted
4236 file I/O (where the remote target uses GDB's file system). See GDB's
4237 remote protocol documentation for details.
4239 * All targets using the new architecture framework.
4241 All of GDB's targets have been updated to use the new internal
4242 architecture framework. The way is now open for future GDB releases
4243 to include cross-architecture native debugging support (i386 on amd64,
4246 * GNU/Linux's Thread Local Storage (TLS)
4248 GDB now includes support for for the GNU/Linux implementation of
4249 per-thread variables.
4251 * GNU/Linux's Native POSIX Thread Library (NPTL)
4253 GDB's thread code has been updated to work with either the new
4254 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4256 * Separate debug info.
4258 GDB, in conjunction with BINUTILS, now supports a mechanism for
4259 automatically loading debug information from a separate file. Instead
4260 of shipping full debug and non-debug versions of system libraries,
4261 system integrators can now instead ship just the stripped libraries
4262 and optional debug files.
4264 * DWARF 2 Location Expressions
4266 DWARF 2 Location Expressions allow the compiler to more completely
4267 describe the location of variables (even in optimized code) to the
4270 GDB now includes preliminary support for location expressions (support
4271 for DW_OP_piece is still missing).
4275 A number of long standing bugs that caused GDB to die while starting a
4276 Java application have been fixed. GDB's Java support is now
4277 considered "useable".
4279 * GNU/Linux support for fork, vfork, and exec.
4281 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4282 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4285 * GDB supports logging output to a file
4287 There are two new commands, "set logging" and "show logging", which can be
4288 used to capture GDB's output to a file.
4290 * The meaning of "detach" has changed for gdbserver
4292 The "detach" command will now resume the application, as documented. To
4293 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4296 * d10v, m68hc11 `regs' command deprecated
4298 The `info registers' command has been updated so that it displays the
4299 registers using a format identical to the old `regs' command.
4303 A new command, "maint set profile on/off", has been added. This command can
4304 be used to enable or disable profiling while running GDB, to profile a
4305 session or a set of commands. In addition there is a new configure switch,
4306 "--enable-profiling", which will cause GDB to be compiled with profiling
4307 data, for more informative profiling results.
4309 * Default MI syntax changed to "mi2".
4311 The default MI (machine interface) syntax, enabled by the command line
4312 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4313 "mi1", can be enabled by specifying the option "-i=mi1".
4315 Support for the original "mi0" syntax (included in GDB 5.0) has been
4318 Fix for gdb/192: removed extraneous space when displaying frame level.
4319 Fix for gdb/672: update changelist is now output in mi list format.
4320 Fix for gdb/702: a -var-assign that updates the value now shows up
4321 in a subsequent -var-update.
4323 * New native configurations.
4325 FreeBSD/amd64 x86_64-*-freebsd*
4327 * Multi-arched targets.
4329 HP/PA HPUX11 hppa*-*-hpux*
4330 Renesas M32R/D w/simulator m32r-*-elf*
4332 * OBSOLETE configurations and files
4334 Configurations that have been declared obsolete in this release have
4335 been commented out. Unless there is activity to revive these
4336 configurations, the next release of GDB will have their sources
4337 permanently REMOVED.
4339 Z8000 simulator z8k-zilog-none or z8ksim
4340 Matsushita MN10200 w/simulator mn10200-*-*
4341 H8/500 simulator h8500-hitachi-hms or h8500hms
4342 HP/PA running BSD hppa*-*-bsd*
4343 HP/PA running OSF/1 hppa*-*-osf*
4344 HP/PA Pro target hppa*-*-pro*
4345 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4346 Sequent family i[3456]86-sequent-sysv4*
4347 i[3456]86-sequent-sysv*
4348 i[3456]86-sequent-bsd*
4349 Tsqware Sparclet sparclet-*-*
4350 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4352 * REMOVED configurations and files
4355 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4356 IBM AIX PS/2 i[3456]86-*-aix
4357 i386 running Mach 3.0 i[3456]86-*-mach3*
4358 i386 running Mach i[3456]86-*-mach*
4359 i386 running OSF/1 i[3456]86-*osf1mk*
4360 HP/Apollo 68k Family m68*-apollo*-sysv*,
4362 m68*-hp-bsd*, m68*-hp-hpux*
4363 Argonaut Risc Chip (ARC) arc-*-*
4364 Mitsubishi D30V d30v-*-*
4365 Fujitsu FR30 fr30-*-elf*
4366 OS/9000 i[34]86-*-os9k
4367 I960 with MON960 i960-*-coff
4369 * MIPS $fp behavior changed
4371 The convenience variable $fp, for the MIPS, now consistently returns
4372 the address of the current frame's base. Previously, depending on the
4373 context, $fp could refer to either $sp or the current frame's base
4374 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4375 The GNU Source-Level Debugger''.
4377 *** Changes in GDB 5.3:
4379 * GNU/Linux shared library multi-threaded performance improved.
4381 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4382 `/proc', in preference to `ptrace' for memory reads. This may result
4383 in an improvement in the start-up time of multi-threaded, shared
4384 library applications when run under GDB. One GDB user writes: ``loads
4385 shared libs like mad''.
4387 * ``gdbserver'' now supports multi-threaded applications on some targets
4389 Support for debugging multi-threaded applications which use
4390 the GNU/Linux LinuxThreads package has been added for
4391 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4392 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4394 * GDB now supports C/C++ preprocessor macros.
4396 GDB now expands preprocessor macro invocations in C/C++ expressions,
4397 and provides various commands for showing macro definitions and how
4400 The new command `macro expand EXPRESSION' expands any macro
4401 invocations in expression, and shows the result.
4403 The new command `show macro MACRO-NAME' shows the definition of the
4404 macro named MACRO-NAME, and where it was defined.
4406 Most compilers don't include information about macros in the debugging
4407 information by default. In GCC 3.1, for example, you need to compile
4408 your program with the options `-gdwarf-2 -g3'. If the macro
4409 information is present in the executable, GDB will read it.
4411 * Multi-arched targets.
4413 DEC Alpha (partial) alpha*-*-*
4414 DEC VAX (partial) vax-*-*
4416 National Semiconductor NS32000 (partial) ns32k-*-*
4417 Motorola 68000 (partial) m68k-*-*
4418 Motorola MCORE mcore-*-*
4422 Fujitsu FRV architecture added by Red Hat frv*-*-*
4425 * New native configurations
4427 Alpha NetBSD alpha*-*-netbsd*
4428 SH NetBSD sh*-*-netbsdelf*
4429 MIPS NetBSD mips*-*-netbsd*
4430 UltraSPARC NetBSD sparc64-*-netbsd*
4432 * OBSOLETE configurations and files
4434 Configurations that have been declared obsolete in this release have
4435 been commented out. Unless there is activity to revive these
4436 configurations, the next release of GDB will have their sources
4437 permanently REMOVED.
4439 Mitsubishi D30V d30v-*-*
4440 OS/9000 i[34]86-*-os9k
4441 IBM AIX PS/2 i[3456]86-*-aix
4442 Fujitsu FR30 fr30-*-elf*
4443 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4444 Argonaut Risc Chip (ARC) arc-*-*
4445 i386 running Mach 3.0 i[3456]86-*-mach3*
4446 i386 running Mach i[3456]86-*-mach*
4447 i386 running OSF/1 i[3456]86-*osf1mk*
4448 HP/Apollo 68k Family m68*-apollo*-sysv*,
4450 m68*-hp-bsd*, m68*-hp-hpux*
4451 I960 with MON960 i960-*-coff
4453 * OBSOLETE languages
4455 CHILL, a Pascal like language used by telecommunications companies.
4457 * REMOVED configurations and files
4459 AMD 29k family via UDI a29k-amd-udi, udi29k
4460 A29K VxWorks a29k-*-vxworks
4461 AMD 29000 embedded, using EBMON a29k-none-none
4462 AMD 29000 embedded with COFF a29k-none-coff
4463 AMD 29000 embedded with a.out a29k-none-aout
4465 testsuite/gdb.hp/gdb.threads-hp/ directory
4467 * New command "set max-user-call-depth <nnn>"
4469 This command allows the user to limit the call depth of user-defined
4470 commands. The default is 1024.
4472 * Changes in FreeBSD/i386 native debugging.
4474 Support for the "generate-core-file" has been added.
4476 * New commands "dump", "append", and "restore".
4478 These commands allow data to be copied from target memory
4479 to a bfd-format or binary file (dump and append), and back
4480 from a file into memory (restore).
4482 * Improved "next/step" support on multi-processor Alpha Tru64.
4484 The previous single-step mechanism could cause unpredictable problems,
4485 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4486 of a software single-step mechanism prevents this.
4488 *** Changes in GDB 5.2.1:
4496 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4497 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4498 Fix, by Joel Brobecker imported from mainline.
4500 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4501 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4502 Fix, by Fred Fish, imported from mainline.
4504 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4505 Surprisingly enough, it works now.
4506 By Michal Ludvig, imported from mainline.
4508 i386 hardware watchpoint support:
4509 avoid misses on second run for some targets.
4510 By Pierre Muller, imported from mainline.
4512 *** Changes in GDB 5.2:
4514 * New command "set trust-readonly-sections on[off]".
4516 This command is a hint that tells gdb that read-only sections
4517 really are read-only (ie. that their contents will not change).
4518 In this mode, gdb will go to the object file rather than the
4519 target to read memory from read-only sections (such as ".text").
4520 This can be a significant performance improvement on some
4521 (notably embedded) targets.
4523 * New command "generate-core-file" (or "gcore").
4525 This new gdb command allows the user to drop a core file of the child
4526 process state at any time. So far it's been implemented only for
4527 GNU/Linux and Solaris, but should be relatively easily ported to other
4528 hosts. Argument is core file name (defaults to core.<pid>).
4530 * New command line option
4532 GDB now accepts --pid or -p followed by a process id.
4534 * Change in command line behavior -- corefiles vs. process ids.
4536 There is a subtle behavior in the way in which GDB handles
4537 command line arguments. The first non-flag argument is always
4538 a program to debug, but the second non-flag argument may either
4539 be a corefile or a process id. Previously, GDB would attempt to
4540 open the second argument as a corefile, and if that failed, would
4541 issue a superfluous error message and then attempt to attach it as
4542 a process. Now, if the second argument begins with a non-digit,
4543 it will be treated as a corefile. If it begins with a digit,
4544 GDB will attempt to attach it as a process, and if no such process
4545 is found, will then attempt to open it as a corefile.
4547 * Changes in ARM configurations.
4549 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4550 configuration is fully multi-arch.
4552 * New native configurations
4554 ARM NetBSD arm*-*-netbsd*
4555 x86 OpenBSD i[3456]86-*-openbsd*
4556 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4557 Sparc64 running FreeBSD sparc64-*-freebsd*
4561 Sanyo XStormy16 xstormy16-elf
4563 * OBSOLETE configurations and files
4565 Configurations that have been declared obsolete in this release have
4566 been commented out. Unless there is activity to revive these
4567 configurations, the next release of GDB will have their sources
4568 permanently REMOVED.
4570 AMD 29k family via UDI a29k-amd-udi, udi29k
4571 A29K VxWorks a29k-*-vxworks
4572 AMD 29000 embedded, using EBMON a29k-none-none
4573 AMD 29000 embedded with COFF a29k-none-coff
4574 AMD 29000 embedded with a.out a29k-none-aout
4576 testsuite/gdb.hp/gdb.threads-hp/ directory
4578 * REMOVED configurations and files
4580 TI TMS320C80 tic80-*-*
4582 PowerPC Solaris powerpcle-*-solaris*
4583 PowerPC Windows NT powerpcle-*-cygwin32
4584 PowerPC Netware powerpc-*-netware*
4585 Harris/CXUX m88k m88*-harris-cxux*
4586 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4587 ns32k-utek-sysv* ns32k-utek-*
4588 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4589 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4590 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4591 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4592 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4594 * Changes to command line processing
4596 The new `--args' feature can be used to specify command-line arguments
4597 for the inferior from gdb's command line.
4599 * Changes to key bindings
4601 There is a new `operate-and-get-next' function bound to `C-o'.
4603 *** Changes in GDB 5.1.1
4605 Fix compile problem on DJGPP.
4607 Fix a problem with floating-point registers on the i386 being
4610 Fix to stop GDB crashing on .debug_str debug info.
4612 Numerous documentation fixes.
4614 Numerous testsuite fixes.
4616 *** Changes in GDB 5.1:
4618 * New native configurations
4620 Alpha FreeBSD alpha*-*-freebsd*
4621 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4622 MIPS GNU/Linux mips*-*-linux*
4623 MIPS SGI Irix 6.x mips*-sgi-irix6*
4624 ia64 AIX ia64-*-aix*
4625 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4629 Motorola 68HC11 and 68HC12 m68hc11-elf
4631 UltraSparc running GNU/Linux sparc64-*-linux*
4633 * OBSOLETE configurations and files
4635 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4636 Harris/CXUX m88k m88*-harris-cxux*
4637 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4638 ns32k-utek-sysv* ns32k-utek-*
4639 TI TMS320C80 tic80-*-*
4641 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4642 PowerPC Solaris powerpcle-*-solaris*
4643 PowerPC Windows NT powerpcle-*-cygwin32
4644 PowerPC Netware powerpc-*-netware*
4645 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4646 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4647 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4648 Apple Macintosh (MPW) host N/A
4650 stuff.c (Program to stuff files into a specially prepared space in kdb)
4651 kdb-start.c (Main loop for the standalone kernel debugger)
4653 Configurations that have been declared obsolete in this release have
4654 been commented out. Unless there is activity to revive these
4655 configurations, the next release of GDB will have their sources
4656 permanently REMOVED.
4658 * REMOVED configurations and files
4660 Altos 3068 m68*-altos-*
4661 Convex c1-*-*, c2-*-*
4663 ARM RISCix arm-*-* (as host)
4667 * GDB has been converted to ISO C.
4669 GDB's source code has been converted to ISO C. In particular, the
4670 sources are fully protoized, and rely on standard headers being
4675 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4677 * The MI enabled by default.
4679 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4680 revised and enabled by default. Packages which use GDB as a debugging
4681 engine behind a UI or another front end are encouraged to switch to
4682 using the GDB/MI interface, instead of the old annotations interface
4683 which is now deprecated.
4685 * Support for debugging Pascal programs.
4687 GDB now includes support for debugging Pascal programs. The following
4688 main features are supported:
4690 - Pascal-specific data types such as sets;
4692 - automatic recognition of Pascal sources based on file-name
4695 - Pascal-style display of data types, variables, and functions;
4697 - a Pascal expression parser.
4699 However, some important features are not yet supported.
4701 - Pascal string operations are not supported at all;
4703 - there are some problems with boolean types;
4705 - Pascal type hexadecimal constants are not supported
4706 because they conflict with the internal variables format;
4708 - support for Pascal objects and classes is not full yet;
4710 - unlike Pascal, GDB is case-sensitive for symbol names.
4712 * Changes in completion.
4714 Commands such as `shell', `run' and `set args', which pass arguments
4715 to inferior programs, now complete on file names, similar to what
4716 users expect at the shell prompt.
4718 Commands which accept locations, such as `disassemble', `print',
4719 `breakpoint', `until', etc. now complete on filenames as well as
4720 program symbols. Thus, if you type "break foob TAB", and the source
4721 files linked into the programs include `foobar.c', that file name will
4722 be one of the candidates for completion. However, file names are not
4723 considered for completion after you typed a colon that delimits a file
4724 name from a name of a function in that file, as in "break foo.c:bar".
4726 `set demangle-style' completes on available demangling styles.
4728 * New platform-independent commands:
4730 It is now possible to define a post-hook for a command as well as a
4731 hook that runs before the command. For more details, see the
4732 documentation of `hookpost' in the GDB manual.
4734 * Changes in GNU/Linux native debugging.
4736 Support for debugging multi-threaded programs has been completely
4737 revised for all platforms except m68k and sparc. You can now debug as
4738 many threads as your system allows you to have.
4740 Attach/detach is supported for multi-threaded programs.
4742 Support for SSE registers was added for x86. This doesn't work for
4743 multi-threaded programs though.
4745 * Changes in MIPS configurations.
4747 Multi-arch support is enabled for all MIPS configurations.
4749 GDB can now be built as native debugger on SGI Irix 6.x systems for
4750 debugging n32 executables. (Debugging 64-bit executables is not yet
4753 * Unified support for hardware watchpoints in all x86 configurations.
4755 Most (if not all) native x86 configurations support hardware-assisted
4756 breakpoints and watchpoints in a unified manner. This support
4757 implements debug register sharing between watchpoints, which allows to
4758 put a virtually infinite number of watchpoints on the same address,
4759 and also supports watching regions up to 16 bytes with several debug
4762 The new maintenance command `maintenance show-debug-regs' toggles
4763 debugging print-outs in functions that insert, remove, and test
4764 watchpoints and hardware breakpoints.
4766 * Changes in the DJGPP native configuration.
4768 New command ``info dos sysinfo'' displays assorted information about
4769 the CPU, OS, memory, and DPMI server.
4771 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4772 display information about segment descriptors stored in GDT, LDT, and
4775 New commands ``info dos pde'' and ``info dos pte'' display entries
4776 from Page Directory and Page Tables (for now works with CWSDPMI only).
4777 New command ``info dos address-pte'' displays the Page Table entry for
4778 a given linear address.
4780 GDB can now pass command lines longer than 126 characters to the
4781 program being debugged (requires an update to the libdbg.a library
4782 which is part of the DJGPP development kit).
4784 DWARF2 debug info is now supported.
4786 It is now possible to `step' and `next' through calls to `longjmp'.
4788 * Changes in documentation.
4790 All GDB documentation was converted to GFDL, the GNU Free
4791 Documentation License.
4793 Tracepoints-related commands are now fully documented in the GDB
4796 TUI, the Text-mode User Interface, is now documented in the manual.
4798 Tracepoints-related commands are now fully documented in the GDB
4801 The "GDB Internals" manual now has an index. It also includes
4802 documentation of `ui_out' functions, GDB coding standards, x86
4803 hardware watchpoints, and memory region attributes.
4805 * GDB's version number moved to ``version.in''
4807 The Makefile variable VERSION has been replaced by the file
4808 ``version.in''. People creating GDB distributions should update the
4809 contents of this file.
4813 GUD support is now a standard part of the EMACS distribution.
4815 *** Changes in GDB 5.0:
4817 * Improved support for debugging FP programs on x86 targets
4819 Unified and much-improved support for debugging floating-point
4820 programs on all x86 targets. In particular, ``info float'' now
4821 displays the FP registers in the same format on all x86 targets, with
4822 greater level of detail.
4824 * Improvements and bugfixes in hardware-assisted watchpoints
4826 It is now possible to watch array elements, struct members, and
4827 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4828 on x86 targets no longer erroneously trigger when the address is
4831 * Improvements in the native DJGPP version of GDB
4833 The distribution now includes all the scripts and auxiliary files
4834 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4835 machines ``out of the box''.
4837 The DJGPP version can now debug programs that use signals. It is
4838 possible to catch signals that happened in the debuggee, deliver
4839 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4840 would kill the program being debugged.) Programs that hook hardware
4841 interrupts (keyboard, timer, etc.) can also be debugged.
4843 It is now possible to debug DJGPP programs that redirect their
4844 standard handles or switch them to raw (as opposed to cooked) mode, or
4845 even close them. The command ``run < foo > bar'' works as expected,
4846 and ``info terminal'' reports useful information about the debuggee's
4847 terminal, including raw/cooked mode, redirection, etc.
4849 The DJGPP version now uses termios functions for console I/O, which
4850 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4853 DOS-style file names with drive letters are now fully supported by
4856 It is now possible to debug DJGPP programs that switch their working
4857 directory. It is also possible to rerun the debuggee any number of
4858 times without restarting GDB; thus, you can use the same setup,
4859 breakpoints, etc. for many debugging sessions.
4861 * New native configurations
4863 ARM GNU/Linux arm*-*-linux*
4864 PowerPC GNU/Linux powerpc-*-linux*
4868 Motorola MCore mcore-*-*
4869 x86 VxWorks i[3456]86-*-vxworks*
4870 PowerPC VxWorks powerpc-*-vxworks*
4871 TI TMS320C80 tic80-*-*
4873 * OBSOLETE configurations
4875 Altos 3068 m68*-altos-*
4876 Convex c1-*-*, c2-*-*
4878 ARM RISCix arm-*-* (as host)
4881 Configurations that have been declared obsolete will be commented out,
4882 but the code will be left in place. If there is no activity to revive
4883 these configurations before the next release of GDB, the sources will
4884 be permanently REMOVED.
4886 * Gould support removed
4888 Support for the Gould PowerNode and NP1 has been removed.
4890 * New features for SVR4
4892 On SVR4 native platforms (such as Solaris), if you attach to a process
4893 without first loading a symbol file, GDB will now attempt to locate and
4894 load symbols from the running process's executable file.
4896 * Many C++ enhancements
4898 C++ support has been greatly improved. Overload resolution now works properly
4899 in almost all cases. RTTI support is on the way.
4901 * Remote targets can connect to a sub-program
4903 A popen(3) style serial-device has been added. This device starts a
4904 sub-process (such as a stand-alone simulator) and then communicates
4905 with that. The sub-program to run is specified using the syntax
4906 ``|<program> <args>'' vis:
4908 (gdb) set remotedebug 1
4909 (gdb) target extended-remote |mn10300-elf-sim program-args
4911 * MIPS 64 remote protocol
4913 A long standing bug in the mips64 remote protocol where by GDB
4914 expected certain 32 bit registers (ex SR) to be transfered as 32
4915 instead of 64 bits has been fixed.
4917 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4918 added to provide backward compatibility with older versions of GDB.
4920 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4922 The command ``set remotebinarydownload'' command has been replaced by
4923 ``set remote X-packet''. Other commands in ``set remote'' family
4924 include ``set remote P-packet''.
4926 * Breakpoint commands accept ranges.
4928 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4929 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4930 ``tracepoint passcount'' also accepts a range of tracepoints.
4932 * ``apropos'' command added.
4934 The ``apropos'' command searches through command names and
4935 documentation strings, printing out matches, making it much easier to
4936 try to find a command that does what you are looking for.
4940 A new machine oriented interface (MI) has been added to GDB. This
4941 interface is designed for debug environments running GDB as a separate
4942 process. This is part of the long term libGDB project. See the
4943 "GDB/MI" chapter of the GDB manual for further information. It can be
4944 enabled by configuring with:
4946 .../configure --enable-gdbmi
4948 *** Changes in GDB-4.18:
4950 * New native configurations
4952 HP-UX 10.20 hppa*-*-hpux10.20
4953 HP-UX 11.x hppa*-*-hpux11.0*
4954 M68K GNU/Linux m68*-*-linux*
4958 Fujitsu FR30 fr30-*-elf*
4959 Intel StrongARM strongarm-*-*
4960 Mitsubishi D30V d30v-*-*
4962 * OBSOLETE configurations
4964 Gould PowerNode, NP1 np1-*-*, pn-*-*
4966 Configurations that have been declared obsolete will be commented out,
4967 but the code will be left in place. If there is no activity to revive
4968 these configurations before the next release of GDB, the sources will
4969 be permanently REMOVED.
4973 As a compatibility experiment, GDB's source files buildsym.h and
4974 buildsym.c have been converted to pure standard C, no longer
4975 containing any K&R compatibility code. We believe that all systems in
4976 use today either come with a standard C compiler, or have a GCC port
4977 available. If this is not true, please report the affected
4978 configuration to bug-gdb@gnu.org immediately. See the README file for
4979 information about getting a standard C compiler if you don't have one
4984 GDB now uses readline 2.2.
4986 * set extension-language
4988 You can now control the mapping between filename extensions and source
4989 languages by using the `set extension-language' command. For instance,
4990 you can ask GDB to treat .c files as C++ by saying
4991 set extension-language .c c++
4992 The command `info extensions' lists all of the recognized extensions
4993 and their associated languages.
4995 * Setting processor type for PowerPC and RS/6000
4997 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4998 you can use the `set processor' command to specify what variant of the
4999 PowerPC family you are debugging. The command
5003 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5004 following PowerPC and RS6000 variants:
5006 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5007 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5009 403GC IBM PowerPC 403GC
5010 505 Motorola PowerPC 505
5011 860 Motorola PowerPC 860 or 850
5012 601 Motorola PowerPC 601
5013 602 Motorola PowerPC 602
5014 603 Motorola/IBM PowerPC 603 or 603e
5015 604 Motorola PowerPC 604 or 604e
5016 750 Motorola/IBM PowerPC 750 or 750
5018 At the moment, this command just tells GDB what to name the
5019 special-purpose processor registers. Since almost all the affected
5020 registers are inaccessible to user-level programs, this command is
5021 only useful for remote debugging in its present form.
5025 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5026 more extensive support for HP-UX. Added features include shared
5027 library support, kernel threads and hardware watchpoints for 11.00,
5028 support for HP's ANSI C and C++ compilers, and a compatibility mode
5029 for xdb and dbx commands.
5033 HP's donation includes the new concept of catchpoints, which is a
5034 generalization of the old catch command. On HP-UX, it is now possible
5035 to catch exec, fork, and vfork, as well as library loading.
5037 This means that the existing catch command has changed; its first
5038 argument now specifies the type of catch to be set up. See the
5039 output of "help catch" for a list of catchpoint types.
5041 * Debugging across forks
5043 On HP-UX, you can choose which process to debug when a fork() happens
5048 HP has donated a curses-based terminal user interface (TUI). To get
5049 it, build with --enable-tui. Although this can be enabled for any
5050 configuration, at present it only works for native HP debugging.
5052 * GDB remote protocol additions
5054 A new protocol packet 'X' that writes binary data is now available.
5055 Default behavior is to try 'X', then drop back to 'M' if the stub
5056 fails to respond. The settable variable `remotebinarydownload'
5057 allows explicit control over the use of 'X'.
5059 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5060 full 64-bit address. The command
5062 set remoteaddresssize 32
5064 can be used to revert to the old behaviour. For existing remote stubs
5065 the change should not be noticed, as the additional address information
5068 In order to assist in debugging stubs, you may use the maintenance
5069 command `packet' to send any text string to the stub. For instance,
5071 maint packet heythere
5073 sends the packet "$heythere#<checksum>". Note that it is very easy to
5074 disrupt a debugging session by sending the wrong packet at the wrong
5077 The compare-sections command allows you to compare section data on the
5078 target to what is in the executable file without uploading or
5079 downloading, by comparing CRC checksums.
5081 * Tracing can collect general expressions
5083 You may now collect general expressions at tracepoints. This requires
5084 further additions to the target-side stub; see tracepoint.c and
5085 doc/agentexpr.texi for further details.
5087 * mask-address variable for Mips
5089 For Mips targets, you may control the zeroing of the upper 32 bits of
5090 a 64-bit address by entering `set mask-address on'. This is mainly
5091 of interest to users of embedded R4xxx and R5xxx processors.
5093 * Higher serial baud rates
5095 GDB's serial code now allows you to specify baud rates 57600, 115200,
5096 230400, and 460800 baud. (Note that your host system may not be able
5097 to achieve all of these rates.)
5101 The i960 configuration now includes an initial implementation of a
5102 builtin simulator, contributed by Jim Wilson.
5105 *** Changes in GDB-4.17:
5107 * New native configurations
5109 Alpha GNU/Linux alpha*-*-linux*
5110 Unixware 2.x i[3456]86-unixware2*
5111 Irix 6.x mips*-sgi-irix6*
5112 PowerPC GNU/Linux powerpc-*-linux*
5113 PowerPC Solaris powerpcle-*-solaris*
5114 Sparc GNU/Linux sparc-*-linux*
5115 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5119 Argonaut Risc Chip (ARC) arc-*-*
5120 Hitachi H8/300S h8300*-*-*
5121 Matsushita MN10200 w/simulator mn10200-*-*
5122 Matsushita MN10300 w/simulator mn10300-*-*
5123 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5124 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5125 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5126 Mitsubishi D10V w/simulator d10v-*-*
5127 Mitsubishi M32R/D w/simulator m32r-*-elf*
5128 Tsqware Sparclet sparclet-*-*
5129 NEC V850 w/simulator v850-*-*
5131 * New debugging protocols
5133 ARM with RDI protocol arm*-*-*
5134 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5135 DDB and LSI variants of PMON protocol mips*-*-*
5136 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5137 PowerPC with SDS protocol powerpc{,le}-*-eabi
5138 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5142 All configurations can now understand and use the DWARF 2 debugging
5143 format. The choice is automatic, if the symbol file contains DWARF 2
5148 GDB now includes basic Java language support. This support is
5149 only useful with Java compilers that produce native machine code.
5151 * solib-absolute-prefix and solib-search-path
5153 For SunOS and SVR4 shared libraries, you may now set the prefix for
5154 loading absolute shared library symbol files, and the search path for
5155 locating non-absolute shared library symbol files.
5157 * Live range splitting
5159 GDB can now effectively debug code for which GCC has performed live
5160 range splitting as part of its optimization. See gdb/doc/LRS for
5161 more details on the expected format of the stabs information.
5165 GDB's support for the GNU Hurd, including thread debugging, has been
5166 updated to work with current versions of the Hurd.
5170 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5171 instruction set. ARM GDB automatically detects when Thumb
5172 instructions are in use, and adjusts disassembly and backtracing
5177 GDB's MIPS target configurations now handle the MIP16 16-bit
5182 GDB now includes support for overlays; if an executable has been
5183 linked such that multiple sections are based at the same address, GDB
5184 will decide which section to use for symbolic info. You can choose to
5185 control the decision manually, using overlay commands, or implement
5186 additional target-side support and use "overlay load-target" to bring
5187 in the overlay mapping. Do "help overlay" for more detail.
5191 The command "info symbol <address>" displays information about
5192 the symbol at the specified address.
5196 The standard remote protocol now includes an extension that allows
5197 asynchronous collection and display of trace data. This requires
5198 extensive support in the target-side debugging stub. Tracing mode
5199 includes a new interaction mode in GDB and new commands: see the
5200 file tracepoint.c for more details.
5204 Configurations for embedded MIPS now include a simulator contributed
5205 by Cygnus Solutions. The simulator supports the instruction sets
5206 of most MIPS variants.
5210 Sparc configurations may now include the ERC32 simulator contributed
5211 by the European Space Agency. The simulator is not built into
5212 Sparc targets by default; configure with --enable-sim to include it.
5216 For target configurations that may include multiple variants of a
5217 basic architecture (such as MIPS and SH), you may now set the
5218 architecture explicitly. "set arch" sets, "info arch" lists
5219 the possible architectures.
5221 *** Changes in GDB-4.16:
5223 * New native configurations
5225 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5226 M68K NetBSD m68k-*-netbsd*
5227 PowerPC AIX 4.x powerpc-*-aix*
5228 PowerPC MacOS powerpc-*-macos*
5229 PowerPC Windows NT powerpcle-*-cygwin32
5230 RS/6000 AIX 4.x rs6000-*-aix4*
5234 ARM with RDP protocol arm-*-*
5235 I960 with MON960 i960-*-coff
5236 MIPS VxWorks mips*-*-vxworks*
5237 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5238 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5240 Matra Sparclet sparclet-*-*
5244 The powerpc-eabi configuration now includes the PSIM simulator,
5245 contributed by Andrew Cagney, with assistance from Mike Meissner.
5246 PSIM is a very elaborate model of the PowerPC, including not only
5247 basic instruction set execution, but also details of execution unit
5248 performance and I/O hardware. See sim/ppc/README for more details.
5252 GDB now works with Solaris 2.5.
5254 * Windows 95/NT native
5256 GDB will now work as a native debugger on Windows 95 and Windows NT.
5257 To build it from source, you must use the "gnu-win32" environment,
5258 which uses a DLL to emulate enough of Unix to run the GNU tools.
5259 Further information, binaries, and sources are available at
5260 ftp.cygnus.com, under pub/gnu-win32.
5262 * dont-repeat command
5264 If a user-defined command includes the command `dont-repeat', then the
5265 command will not be repeated if the user just types return. This is
5266 useful if the command is time-consuming to run, so that accidental
5267 extra keystrokes don't run the same command many times.
5269 * Send break instead of ^C
5271 The standard remote protocol now includes an option to send a break
5272 rather than a ^C to the target in order to interrupt it. By default,
5273 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5275 * Remote protocol timeout
5277 The standard remote protocol includes a new variable `remotetimeout'
5278 that allows you to set the number of seconds before GDB gives up trying
5279 to read from the target. The default value is 2.
5281 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5283 By default GDB will automatically keep track of objects as they are
5284 loaded and unloaded by the dynamic linker. By using the command `set
5285 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5286 when shared library events occur, thus allowing you to set breakpoints
5287 in shared libraries which are explicitly loaded by the inferior.
5289 Note this feature does not work on hpux8. On hpux9 you must link
5290 /usr/lib/end.o into your program. This feature should work
5291 automatically on hpux10.
5293 * Irix 5.x hardware watchpoint support
5295 Irix 5 configurations now support the use of hardware watchpoints.
5297 * Mips protocol "SYN garbage limit"
5299 When debugging a Mips target using the `target mips' protocol, you
5300 may set the number of characters that GDB will ignore by setting
5301 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5302 every character. The default value is 1050.
5304 * Recording and replaying remote debug sessions
5306 If you set `remotelogfile' to the name of a file, gdb will write to it
5307 a recording of a remote debug session. This recording may then be
5308 replayed back to gdb using "gdbreplay". See gdbserver/README for
5309 details. This is useful when you have a problem with GDB while doing
5310 remote debugging; you can make a recording of the session and send it
5311 to someone else, who can then recreate the problem.
5313 * Speedups for remote debugging
5315 GDB includes speedups for downloading and stepping MIPS systems using
5316 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5317 and more efficient S-record downloading.
5319 * Memory use reductions and statistics collection
5321 GDB now uses less memory and reports statistics about memory usage.
5322 Try the `maint print statistics' command, for example.
5324 *** Changes in GDB-4.15:
5326 * Psymtabs for XCOFF
5328 The symbol reader for AIX GDB now uses partial symbol tables. This
5329 can greatly improve startup time, especially for large executables.
5331 * Remote targets use caching
5333 Remote targets now use a data cache to speed up communication with the
5334 remote side. The data cache could lead to incorrect results because
5335 it doesn't know about volatile variables, thus making it impossible to
5336 debug targets which use memory mapped I/O devices. `set remotecache
5337 off' turns the the data cache off.
5339 * Remote targets may have threads
5341 The standard remote protocol now includes support for multiple threads
5342 in the target system, using new protocol commands 'H' and 'T'. See
5343 gdb/remote.c for details.
5347 If GDB is configured with `--enable-netrom', then it will include
5348 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5349 acts as though it is a bank of ROM on the target board, but you can
5350 write into it over the network. GDB's support consists only of
5351 support for fast loading into the emulated ROM; to debug, you must use
5352 another protocol, such as standard remote protocol. The usual
5353 sequence is something like
5355 target nrom <netrom-hostname>
5357 target remote <netrom-hostname>:1235
5361 GDB now includes support for the Apple Macintosh, as a host only. It
5362 may be run as either an MPW tool or as a standalone application, and
5363 it can debug through the serial port. All the usual GDB commands are
5364 available, but to the target command, you must supply "serial" as the
5365 device type instead of "/dev/ttyXX". See mpw-README in the main
5366 directory for more information on how to build. The MPW configuration
5367 scripts */mpw-config.in support only a few targets, and only the
5368 mips-idt-ecoff target has been tested.
5372 GDB configuration now uses autoconf. This is not user-visible,
5373 but does simplify configuration and building.
5377 GDB now supports hpux10.
5379 *** Changes in GDB-4.14:
5381 * New native configurations
5383 x86 FreeBSD i[345]86-*-freebsd
5384 x86 NetBSD i[345]86-*-netbsd
5385 NS32k NetBSD ns32k-*-netbsd
5386 Sparc NetBSD sparc-*-netbsd
5390 A29K VxWorks a29k-*-vxworks
5391 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5392 CPU32 EST-300 emulator m68*-*-est*
5393 PowerPC ELF powerpc-*-elf
5396 * Alpha OSF/1 support for procfs
5398 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5399 possible to attach to running processes. As the mounting of the /proc
5400 filesystem is optional on the Alpha, GDB automatically determines
5401 the availability of /proc during startup. This can lead to problems
5402 if /proc is unmounted after GDB has been started.
5404 * Arguments to user-defined commands
5406 User commands may accept up to 10 arguments separated by whitespace.
5407 Arguments are accessed within the user command via $arg0..$arg9. A
5410 print $arg0 + $arg1 + $arg2
5412 To execute the command use:
5415 Defines the command "adder" which prints the sum of its three arguments.
5416 Note the arguments are text substitutions, so they may reference variables,
5417 use complex expressions, or even perform inferior function calls.
5419 * New `if' and `while' commands
5421 This makes it possible to write more sophisticated user-defined
5422 commands. Both commands take a single argument, which is the
5423 expression to evaluate, and must be followed by the commands to
5424 execute, one per line, if the expression is nonzero, the list being
5425 terminated by the word `end'. The `if' command list may include an
5426 `else' word, which causes the following commands to be executed only
5427 if the expression is zero.
5429 * Fortran source language mode
5431 GDB now includes partial support for Fortran 77. It will recognize
5432 Fortran programs and can evaluate a subset of Fortran expressions, but
5433 variables and functions may not be handled correctly. GDB will work
5434 with G77, but does not yet know much about symbols emitted by other
5437 * Better HPUX support
5439 Most debugging facilities now work on dynamic executables for HPPAs
5440 running hpux9 or later. You can attach to running dynamically linked
5441 processes, but by default the dynamic libraries will be read-only, so
5442 for instance you won't be able to put breakpoints in them. To change
5443 that behavior do the following before running the program:
5449 This will cause the libraries to be mapped private and read-write.
5450 To revert to the normal behavior, do this:
5456 You cannot set breakpoints or examine data in the library until after
5457 the library is loaded if the function/data symbols do not have
5460 GDB can now also read debug symbols produced by the HP C compiler on
5461 HPPAs (sorry, no C++, Fortran or 68k support).
5463 * Target byte order now dynamically selectable
5465 You can choose which byte order to use with a target system, via the
5466 commands "set endian big" and "set endian little", and you can see the
5467 current setting by using "show endian". You can also give the command
5468 "set endian auto", in which case GDB will use the byte order
5469 associated with the executable. Currently, only embedded MIPS
5470 configurations support dynamic selection of target byte order.
5472 * New DOS host serial code
5474 This version uses DPMI interrupts to handle buffered I/O, so you
5475 no longer need to run asynctsr when debugging boards connected to
5478 *** Changes in GDB-4.13:
5480 * New "complete" command
5482 This lists all the possible completions for the rest of the line, if it
5483 were to be given as a command itself. This is intended for use by emacs.
5485 * Trailing space optional in prompt
5487 "set prompt" no longer adds a space for you after the prompt you set. This
5488 allows you to set a prompt which ends in a space or one that does not.
5490 * Breakpoint hit counts
5492 "info break" now displays a count of the number of times the breakpoint
5493 has been hit. This is especially useful in conjunction with "ignore"; you
5494 can ignore a large number of breakpoint hits, look at the breakpoint info
5495 to see how many times the breakpoint was hit, then run again, ignoring one
5496 less than that number, and this will get you quickly to the last hit of
5499 * Ability to stop printing at NULL character
5501 "set print null-stop" will cause GDB to stop printing the characters of
5502 an array when the first NULL is encountered. This is useful when large
5503 arrays actually contain only short strings.
5505 * Shared library breakpoints
5507 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5508 breakpoints in shared libraries before the executable is run.
5510 * Hardware watchpoints
5512 There is a new hardware breakpoint for the watch command for sparclite
5513 targets. See gdb/sparclite/hw_breakpoint.note.
5515 Hardware watchpoints are also now supported under GNU/Linux.
5519 Annotations have been added. These are for use with graphical interfaces,
5520 and are still experimental. Currently only gdba.el uses these.
5522 * Improved Irix 5 support
5524 GDB now works properly with Irix 5.2.
5526 * Improved HPPA support
5528 GDB now works properly with the latest GCC and GAS.
5530 * New native configurations
5532 Sequent PTX4 i[34]86-sequent-ptx4
5533 HPPA running OSF/1 hppa*-*-osf*
5534 Atari TT running SVR4 m68*-*-sysv4*
5535 RS/6000 LynxOS rs6000-*-lynxos*
5539 OS/9000 i[34]86-*-os9k
5540 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5543 * Hitachi SH7000 and E7000-PC ICE support
5545 There is now support for communicating with the Hitachi E7000-PC ICE.
5546 This is available automatically when GDB is configured for the SH.
5550 As usual, a variety of small fixes and improvements, both generic
5551 and configuration-specific. See the ChangeLog for more detail.
5553 *** Changes in GDB-4.12:
5555 * Irix 5 is now supported
5559 GDB-4.12 on the HPPA has a number of changes which make it unable
5560 to debug the output from the currently released versions of GCC and
5561 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5562 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5563 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5566 *** Changes in GDB-4.11:
5568 * User visible changes:
5572 The "set remotedebug" option is now consistent between the mips remote
5573 target, remote targets using the gdb-specific protocol, UDI (AMD's
5574 debug protocol for the 29k) and the 88k bug monitor. It is now an
5575 integer specifying a debug level (normally 0 or 1, but 2 means more
5576 debugging info for the mips target).
5578 * DEC Alpha native support
5580 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5581 debug info, but GDB works fairly well with the DEC compiler and should
5582 work with a future GCC release. See the README file for a few
5583 Alpha-specific notes.
5585 * Preliminary thread implementation
5587 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5589 * LynxOS native and target support for 386
5591 This release has been hosted on LynxOS 2.2, and also can be configured
5592 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5595 * Improvements in C++ mangling/demangling.
5597 This release has much better g++ debugging, specifically in name
5598 mangling/demangling, virtual function calls, print virtual table,
5599 call methods, ...etc.
5601 *** Changes in GDB-4.10:
5603 * User visible changes:
5605 Remote debugging using the GDB-specific (`target remote') protocol now
5606 supports the `load' command. This is only useful if you have some
5607 other way of getting the stub to the target system, and you can put it
5608 somewhere in memory where it won't get clobbered by the download.
5610 Filename completion now works.
5612 When run under emacs mode, the "info line" command now causes the
5613 arrow to point to the line specified. Also, "info line" prints
5614 addresses in symbolic form (as well as hex).
5616 All vxworks based targets now support a user settable option, called
5617 vxworks-timeout. This option represents the number of seconds gdb
5618 should wait for responses to rpc's. You might want to use this if
5619 your vxworks target is, perhaps, a slow software simulator or happens
5620 to be on the far side of a thin network line.
5624 This release contains support for using a DEC alpha as a GDB host for
5625 cross debugging. Native alpha debugging is not supported yet.
5628 *** Changes in GDB-4.9:
5632 This is the first GDB release which is accompanied by a matching testsuite.
5633 The testsuite requires installation of dejagnu, which should be available
5634 via ftp from most sites that carry GNU software.
5638 'Cfront' style demangling has had its name changed to 'ARM' style, to
5639 emphasize that it was written from the specifications in the C++ Annotated
5640 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5641 disclaimers, it still generated too much confusion with users attempting to
5642 use gdb with AT&T cfront.
5646 GDB now uses a standard remote interface to a simulator library.
5647 So far, the library contains simulators for the Zilog Z8001/2, the
5648 Hitachi H8/300, H8/500 and Super-H.
5650 * New targets supported
5652 H8/300 simulator h8300-hitachi-hms or h8300hms
5653 H8/500 simulator h8500-hitachi-hms or h8500hms
5654 SH simulator sh-hitachi-hms or sh
5655 Z8000 simulator z8k-zilog-none or z8ksim
5656 IDT MIPS board over serial line mips-idt-ecoff
5658 Cross-debugging to GO32 targets is supported. It requires a custom
5659 version of the i386-stub.c module which is integrated with the
5660 GO32 memory extender.
5662 * New remote protocols
5664 MIPS remote debugging protocol.
5666 * New source languages supported
5668 This version includes preliminary support for Chill, a Pascal like language
5669 used by telecommunications companies. Chill support is also being integrated
5670 into the GNU compiler, but we don't know when it will be publically available.
5673 *** Changes in GDB-4.8:
5675 * HP Precision Architecture supported
5677 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5678 version of this support was available as a set of patches from the
5679 University of Utah. GDB does not support debugging of programs
5680 compiled with the HP compiler, because HP will not document their file
5681 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5682 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5684 Many problems in the preliminary version have been fixed.
5686 * Faster and better demangling
5688 We have improved template demangling and fixed numerous bugs in the GNU style
5689 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5690 character types (wchar_t) are now supported. Demangling of each symbol is now
5691 only done once, and is cached when the symbol table for a file is read in.
5692 This results in a small increase in memory usage for C programs, a moderate
5693 increase in memory usage for C++ programs, and a fantastic speedup in
5696 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5697 from the specifications in the Annotated Reference Manual, which AT&T's
5698 compiler does not actually implement.
5700 * G++ multiple inheritance compiler problem
5702 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5703 inheritance lattices was reworked to properly discover ambiguities. We
5704 recently found an example which causes this new algorithm to fail in a
5705 very subtle way, producing bad debug information for those classes.
5706 The file 'gcc.patch' (in this directory) can be applied to gcc to
5707 circumvent the problem. A future GCC release will contain a complete
5710 The previous G++ debug info problem (mentioned below for the gdb-4.7
5711 release) is fixed in gcc version 2.3.2.
5713 * Improved configure script
5715 The `configure' script will now attempt to guess your system type if
5716 you don't supply a host system type. The old scheme of supplying a
5717 host system triplet is preferable over using this. All the magic is
5718 done in the new `config.guess' script. Examine it for details.
5720 We have also brought our configure script much more in line with the FSF's
5721 version. It now supports the --with-xxx options. In particular,
5722 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5723 The resulting GDB will not be able to read arbitrary object file formats --
5724 only the format ``expected'' to be used on the configured target system.
5725 We hope to make this the default in a future release.
5727 * Documentation improvements
5729 There's new internal documentation on how to modify GDB, and how to
5730 produce clean changes to the code. We implore people to read it
5731 before submitting changes.
5733 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5734 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5735 `info' files are also provided. To build `info' files from scratch,
5736 you will need the latest `makeinfo' release, which will be available in
5737 a future texinfo-X.Y release.
5739 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5740 We're not sure exactly which versions have this problem, but it has
5741 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5742 or better. If that isn't possible, there is a patch in
5743 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5744 around this problem.
5748 GDB now supports array constants that can be used in expressions typed in by
5749 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5750 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5753 The new directory `gdb/sparclite' contains a program that demonstrates
5754 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5756 * New native hosts supported
5758 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5759 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5761 * New targets supported
5763 AMD 29k family via UDI a29k-amd-udi or udi29k
5765 * New file formats supported
5767 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5768 HPUX core files, and SCO 3.2v2 core files.
5772 Attaching to processes now works again; thanks for the many bug reports.
5774 We have also stomped on a bunch of core dumps caused by
5775 printf_filtered("%s") problems.
5777 We eliminated a copyright problem on the rpc and ptrace header files
5778 for VxWorks, which was discovered at the last minute during the 4.7
5779 release. You should now be able to build a VxWorks GDB.
5781 You can now interrupt gdb while an attached process is running. This
5782 will cause the attached process to stop, and give control back to GDB.
5784 We fixed problems caused by using too many file descriptors
5785 for reading symbols from object files and libraries. This was
5786 especially a problem for programs that used many (~100) shared
5789 The `step' command now only enters a subroutine if there is line number
5790 information for the subroutine. Otherwise it acts like the `next'
5791 command. Previously, `step' would enter subroutines if there was
5792 any debugging information about the routine. This avoids problems
5793 when using `cc -g1' on MIPS machines.
5795 * Internal improvements
5797 GDB's internal interfaces have been improved to make it easier to support
5798 debugging of multiple languages in the future.
5800 GDB now uses a common structure for symbol information internally.
5801 Minimal symbols (derived from linkage symbols in object files), partial
5802 symbols (from a quick scan of debug information), and full symbols
5803 contain a common subset of information, making it easier to write
5804 shared code that handles any of them.
5806 * New command line options
5808 We now accept --silent as an alias for --quiet.
5812 The memory-mapped-malloc library is now licensed under the GNU Library
5813 General Public License.
5815 *** Changes in GDB-4.7:
5817 * Host/native/target split
5819 GDB has had some major internal surgery to untangle the support for
5820 hosts and remote targets. Now, when you configure GDB for a remote
5821 target, it will no longer load in all of the support for debugging
5822 local programs on the host. When fully completed and tested, this will
5823 ensure that arbitrary host/target combinations are possible.
5825 The primary conceptual shift is to separate the non-portable code in
5826 GDB into three categories. Host specific code is required any time GDB
5827 is compiled on that host, regardless of the target. Target specific
5828 code relates to the peculiarities of the target, but can be compiled on
5829 any host. Native specific code is everything else: it can only be
5830 built when the host and target are the same system. Child process
5831 handling and core file support are two common `native' examples.
5833 GDB's use of /proc for controlling Unix child processes is now cleaner.
5834 It has been split out into a single module under the `target_ops' vector,
5835 plus two native-dependent functions for each system that uses /proc.
5837 * New hosts supported
5839 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5840 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5841 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5843 * New targets supported
5845 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5846 68030 and CPU32 m68030-*-*, m68332-*-*
5848 * New native hosts supported
5850 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5851 (386bsd is not well tested yet)
5852 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5854 * New file formats supported
5856 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5857 supports reading of `a.out.adobe' object files, which are an a.out
5858 format extended with minimal information about multiple sections.
5862 `show copying' is the same as the old `info copying'.
5863 `show warranty' is the same as `info warrantee'.
5864 These were renamed for consistency. The old commands continue to work.
5866 `info handle' is a new alias for `info signals'.
5868 You can now define pre-command hooks, which attach arbitrary command
5869 scripts to any command. The commands in the hook will be executed
5870 prior to the user's command. You can also create a hook which will be
5871 executed whenever the program stops. See gdb.texinfo.
5875 We now deal with Cfront style name mangling, and can even extract type
5876 info from mangled symbols. GDB can automatically figure out which
5877 symbol mangling style your C++ compiler uses.
5879 Calling of methods and virtual functions has been improved as well.
5883 The crash that occured when debugging Sun Ansi-C compiled binaries is
5884 fixed. This was due to mishandling of the extra N_SO stabs output
5887 We also finally got Ultrix 4.2 running in house, and fixed core file
5888 support, with help from a dozen people on the net.
5890 John M. Farrell discovered that the reason that single-stepping was so
5891 slow on all of the Mips based platforms (primarily SGI and DEC) was
5892 that we were trying to demangle and lookup a symbol used for internal
5893 purposes on every instruction that was being stepped through. Changing
5894 the name of that symbol so that it couldn't be mistaken for a C++
5895 mangled symbol sped things up a great deal.
5897 Rich Pixley sped up symbol lookups in general by getting much smarter
5898 about when C++ symbol mangling is necessary. This should make symbol
5899 completion (TAB on the command line) much faster. It's not as fast as
5900 we'd like, but it's significantly faster than gdb-4.6.
5904 A new user controllable variable 'call_scratch_address' can
5905 specify the location of a scratch area to be used when GDB
5906 calls a function in the target. This is necessary because the
5907 usual method of putting the scratch area on the stack does not work
5908 in systems that have separate instruction and data spaces.
5910 We integrated changes to support the 29k UDI (Universal Debugger
5911 Interface), but discovered at the last minute that we didn't have all
5912 of the appropriate copyright paperwork. We are working with AMD to
5913 resolve this, and hope to have it available soon.
5917 We have sped up the remote serial line protocol, especially for targets
5918 with lots of registers. It now supports a new `expedited status' ('T')
5919 message which can be used in place of the existing 'S' status message.
5920 This allows the remote stub to send only the registers that GDB
5921 needs to make a quick decision about single-stepping or conditional
5922 breakpoints, eliminating the need to fetch the entire register set for
5923 each instruction being stepped through.
5925 The GDB remote serial protocol now implements a write-through cache for
5926 registers, only re-reading the registers if the target has run.
5928 There is also a new remote serial stub for SPARC processors. You can
5929 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5930 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5931 processor with a serial port.
5935 Configure.in files have become much easier to read and modify. A new
5936 `table driven' format makes it more obvious what configurations are
5937 supported, and what files each one uses.
5941 There is a new opcodes library which will eventually contain all of the
5942 disassembly routines and opcode tables. At present, it only contains
5943 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5944 disassembler (binutils/objdump) to share these routines.
5946 The libiberty library is now copylefted under the GNU Library General
5947 Public License. This allows more liberal use, and was done so libg++
5948 can use it. This makes no difference to GDB, since the Library License
5949 grants all the rights from the General Public License.
5953 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5954 reference to the stabs symbol info used by the debugger. It is (as far
5955 as we know) the only published document on this fascinating topic. We
5956 encourage you to read it, compare it to the stabs information on your
5957 system, and send improvements on the document in general (to
5958 bug-gdb@prep.ai.mit.edu).
5960 And, of course, many bugs have been fixed.
5963 *** Changes in GDB-4.6:
5965 * Better support for C++ function names
5967 GDB now accepts as input the "demangled form" of C++ overloaded function
5968 names and member function names, and can do command completion on such names
5969 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5970 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5971 Make use of command completion, it is your friend.
5973 GDB also now accepts a variety of C++ mangled symbol formats. They are
5974 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5975 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5976 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5977 for the list of formats.
5979 * G++ symbol mangling problem
5981 Recent versions of gcc have a bug in how they emit debugging information for
5982 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5983 directory) can be applied to gcc to fix the problem. Alternatively, if you
5984 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5985 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5986 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5989 * New 'maintenance' command
5991 All of the commands related to hacking GDB internals have been moved out of
5992 the main command set, and now live behind the 'maintenance' command. This
5993 can also be abbreviated as 'mt'. The following changes were made:
5995 dump-me -> maintenance dump-me
5996 info all-breakpoints -> maintenance info breakpoints
5997 printmsyms -> maintenance print msyms
5998 printobjfiles -> maintenance print objfiles
5999 printpsyms -> maintenance print psymbols
6000 printsyms -> maintenance print symbols
6002 The following commands are new:
6004 maintenance demangle Call internal GDB demangler routine to
6005 demangle a C++ link name and prints the result.
6006 maintenance print type Print a type chain for a given symbol
6008 * Change to .gdbinit file processing
6010 We now read the $HOME/.gdbinit file before processing the argv arguments
6011 (e.g. reading symbol files or core files). This allows global parameters to
6012 be set, which will apply during the symbol reading. The ./.gdbinit is still
6013 read after argv processing.
6015 * New hosts supported
6017 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6019 GNU/Linux support i386-unknown-linux or linux
6021 We are also including code to support the HP/PA running BSD and HPUX. This
6022 is almost guaranteed not to work, as we didn't have time to test or build it
6023 for this release. We are including it so that the more adventurous (or
6024 masochistic) of you can play with it. We also had major problems with the
6025 fact that the compiler that we got from HP doesn't support the -g option.
6028 * New targets supported
6030 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6032 * More smarts about finding #include files
6034 GDB now remembers the compilation directory for all include files, and for
6035 all files from which C is generated (like yacc and lex sources). This
6036 greatly improves GDB's ability to find yacc/lex sources, and include files,
6037 especially if you are debugging your program from a directory different from
6038 the one that contains your sources.
6040 We also fixed a bug which caused difficulty with listing and setting
6041 breakpoints in include files which contain C code. (In the past, you had to
6042 try twice in order to list an include file that you hadn't looked at before.)
6044 * Interesting infernals change
6046 GDB now deals with arbitrary numbers of sections, where the symbols for each
6047 section must be relocated relative to that section's landing place in the
6048 target's address space. This work was needed to support ELF with embedded
6049 stabs used by Solaris-2.0.
6051 * Bug fixes (of course!)
6053 There have been loads of fixes for the following things:
6054 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6055 i960, stabs, DOS(GO32), procfs, etc...
6057 See the ChangeLog for details.
6059 *** Changes in GDB-4.5:
6061 * New machines supported (host and target)
6063 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6065 SGI Irix-4.x mips-sgi-irix4 or iris4
6067 * New malloc package
6069 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6070 Mmalloc is capable of handling mutiple heaps of memory. It is also
6071 capable of saving a heap to a file, and then mapping it back in later.
6072 This can be used to greatly speedup the startup of GDB by using a
6073 pre-parsed symbol table which lives in a mmalloc managed heap. For
6074 more details, please read mmalloc/mmalloc.texi.
6078 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6079 'help info proc' for details.
6081 * MIPS ecoff symbol table format
6083 The code that reads MIPS symbol table format is now supported on all hosts.
6084 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6087 * File name changes for MS-DOS
6089 Many files in the config directories have been renamed to make it easier to
6090 support GDB on MS-DOSe systems (which have very restrictive file name
6091 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6092 environment) is close to working but has some remaining problems. Note
6093 that debugging of DOS programs is not supported, due to limitations
6094 in the ``operating system'', but it can be used to host cross-debugging.
6096 * Cross byte order fixes
6098 Many fixes have been made to support cross debugging of Sparc and MIPS
6099 targets from hosts whose byte order differs.
6101 * New -mapped and -readnow options
6103 If memory-mapped files are available on your system through the 'mmap'
6104 system call, you can use the -mapped option on the `file' or
6105 `symbol-file' commands to cause GDB to write the symbols from your
6106 program into a reusable file. If the program you are debugging is
6107 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6108 Future GDB debugging sessions will notice the presence of this file,
6109 and will quickly map in symbol information from it, rather than reading
6110 the symbol table from the executable program. Using the '-mapped'
6111 option in a GDB `file' or `symbol-file' command has the same effect as
6112 starting GDB with the '-mapped' command-line option.
6114 You can cause GDB to read the entire symbol table immediately by using
6115 the '-readnow' option with any of the commands that load symbol table
6116 information (or on the GDB command line). This makes the command
6117 slower, but makes future operations faster.
6119 The -mapped and -readnow options are typically combined in order to
6120 build a `fred.syms' file that contains complete symbol information.
6121 A simple GDB invocation to do nothing but build a `.syms' file for future
6124 gdb -batch -nx -mapped -readnow programname
6126 The `.syms' file is specific to the host machine on which GDB is run.
6127 It holds an exact image of GDB's internal symbol table. It cannot be
6128 shared across multiple host platforms.
6130 * longjmp() handling
6132 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6133 siglongjmp() without losing control. This feature has not yet been ported to
6134 all systems. It currently works on many 386 platforms, all MIPS-based
6135 platforms (SGI, DECstation, etc), and Sun3/4.
6139 Preliminary work has been put in to support the new Solaris OS from Sun. At
6140 this time, it can control and debug processes, but it is not capable of
6145 As always, many many bug fixes. The major areas were with g++, and mipsread.
6146 People using the MIPS-based platforms should experience fewer mysterious
6147 crashes and trashed symbol tables.
6149 *** Changes in GDB-4.4:
6151 * New machines supported (host and target)
6153 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6155 BSD Reno on Vax vax-dec-bsd
6156 Ultrix on Vax vax-dec-ultrix
6158 * New machines supported (target)
6160 AMD 29000 embedded, using EBMON a29k-none-none
6164 GDB continues to improve its handling of C++. `References' work better.
6165 The demangler has also been improved, and now deals with symbols mangled as
6166 per the Annotated C++ Reference Guide.
6168 GDB also now handles `stabs' symbol information embedded in MIPS
6169 `ecoff' symbol tables. Since the ecoff format was not easily
6170 extensible to handle new languages such as C++, this appeared to be a
6171 good way to put C++ debugging info into MIPS binaries. This option
6172 will be supported in the GNU C compiler, version 2, when it is
6175 * New features for SVR4
6177 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6178 shared libraries. Debugging dynamically linked programs should present
6179 only minor differences from debugging statically linked programs.
6181 The `info proc' command will print out information about any process
6182 on an SVR4 system (including the one you are debugging). At the moment,
6183 it prints the address mappings of the process.
6185 If you bring up GDB on another SVR4 system, please send mail to
6186 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6188 * Better dynamic linking support in SunOS
6190 Reading symbols from shared libraries which contain debugging symbols
6191 now works properly. However, there remain issues such as automatic
6192 skipping of `transfer vector' code during function calls, which
6193 make it harder to debug code in a shared library, than to debug the
6194 same code linked statically.
6198 GDB is now using the latest `getopt' routines from the FSF. This
6199 version accepts the -- prefix for options with long names. GDB will
6200 continue to accept the old forms (-option and +option) as well.
6201 Various single letter abbreviations for options have been explicity
6202 added to the option table so that they won't get overshadowed in the
6203 future by other options that begin with the same letter.
6207 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6208 Many assorted bugs have been handled. Many more remain to be handled.
6209 See the various ChangeLog files (primarily in gdb and bfd) for details.
6212 *** Changes in GDB-4.3:
6214 * New machines supported (host and target)
6216 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6217 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6218 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6220 * Almost SCO Unix support
6222 We had hoped to support:
6223 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6224 (except for core file support), but we discovered very late in the release
6225 that it has problems with process groups that render gdb unusable. Sorry
6226 about that. I encourage people to fix it and post the fixes.
6228 * Preliminary ELF and DWARF support
6230 GDB can read ELF object files on System V Release 4, and can handle
6231 debugging records for C, in DWARF format, in ELF files. This support
6232 is preliminary. If you bring up GDB on another SVR4 system, please
6233 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6238 GDB now uses the latest `readline' library. One user-visible change
6239 is that two tabs will list possible command completions, which previously
6240 required typing M-? (meta-question mark, or ESC ?).
6244 The `stepi' bug that many of you noticed has been squashed.
6245 Many bugs in C++ have been handled. Many more remain to be handled.
6246 See the various ChangeLog files (primarily in gdb and bfd) for details.
6248 * State of the MIPS world (in case you wondered):
6250 GDB can understand the symbol tables emitted by the compilers
6251 supplied by most vendors of MIPS-based machines, including DEC. These
6252 symbol tables are in a format that essentially nobody else uses.
6254 Some versions of gcc come with an assembler post-processor called
6255 mips-tfile. This program is required if you want to do source-level
6256 debugging of gcc-compiled programs. I believe FSF does not ship
6257 mips-tfile with gcc version 1, but it will eventually come with gcc
6260 Debugging of g++ output remains a problem. g++ version 1.xx does not
6261 really support it at all. (If you're lucky, you should be able to get
6262 line numbers and stack traces to work, but no parameters or local
6263 variables.) With some work it should be possible to improve the
6266 When gcc version 2 is released, you will have somewhat better luck.
6267 However, even then you will get confusing results for inheritance and
6270 We will eventually provide full debugging of g++ output on
6271 DECstations. This will probably involve some kind of stabs-in-ecoff
6272 encapulation, but the details have not been worked out yet.
6275 *** Changes in GDB-4.2:
6277 * Improved configuration
6279 Only one copy of `configure' exists now, and it is not self-modifying.
6280 Porting BFD is simpler.
6284 The `step' and `next' commands now only stop at the first instruction
6285 of a source line. This prevents the multiple stops that used to occur
6286 in switch statements, for-loops, etc. `Step' continues to stop if a
6287 function that has debugging information is called within the line.
6291 Lots of small bugs fixed. More remain.
6293 * New host supported (not target)
6295 Intel 386 PC clone running Mach i386-none-mach
6298 *** Changes in GDB-4.1:
6300 * Multiple source language support
6302 GDB now has internal scaffolding to handle several source languages.
6303 It determines the type of each source file from its filename extension,
6304 and will switch expression parsing and number formatting to match the
6305 language of the function in the currently selected stack frame.
6306 You can also specifically set the language to be used, with
6307 `set language c' or `set language modula-2'.
6311 GDB now has preliminary support for the GNU Modula-2 compiler,
6312 currently under development at the State University of New York at
6313 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6314 continue through the fall of 1991 and into 1992.
6316 Other Modula-2 compilers are currently not supported, and attempting to
6317 debug programs compiled with them will likely result in an error as the
6318 symbol table is read. Feel free to work on it, though!
6320 There are hooks in GDB for strict type checking and range checking,
6321 in the `Modula-2 philosophy', but they do not currently work.
6325 GDB can now write to executable and core files (e.g. patch
6326 a variable's value). You must turn this switch on, specify
6327 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6328 by assigning a new value to a variable. Modifications take
6331 * Automatic SunOS shared library reading
6333 When you run your program, GDB automatically determines where its
6334 shared libraries (if any) have been loaded, and reads their symbols.
6335 The `share' command is no longer needed. This also works when
6336 examining core files.
6340 You can specify the number of lines that the `list' command shows.
6343 * New machines supported (host and target)
6345 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6346 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6347 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6349 * New hosts supported (not targets)
6351 IBM RT/PC: romp-ibm-aix or rtpc
6353 * New targets supported (not hosts)
6355 AMD 29000 embedded with COFF a29k-none-coff
6356 AMD 29000 embedded with a.out a29k-none-aout
6357 Ultracomputer remote kernel debug a29k-nyu-kern
6359 * New remote interfaces
6365 *** Changes in GDB-4.0:
6369 Wide output is wrapped at good places to make the output more readable.
6371 Gdb now supports cross-debugging from a host machine of one type to a
6372 target machine of another type. Communication with the target system
6373 is over serial lines. The ``target'' command handles connecting to the
6374 remote system; the ``load'' command will download a program into the
6375 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6376 also supports debugging of realtime processes running under VxWorks,
6377 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6378 stub on the target system.
6380 New CPUs supported include the AMD 29000 and Intel 960.
6382 GDB now reads object files and symbol tables via a ``binary file''
6383 library, which allows a single copy of GDB to debug programs of multiple
6384 object file types such as a.out and coff.
6386 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6387 refcard.dvi and refcard.ps are available to format it).
6390 * Control-Variable user interface simplified
6392 All variables that control the operation of the debugger can be set
6393 by the ``set'' command, and displayed by the ``show'' command.
6395 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6396 ``Show prompt'' produces the response:
6397 Gdb's prompt is new-gdb=>.
6399 What follows are the NEW set commands. The command ``help set'' will
6400 print a complete list of old and new set commands. ``help set FOO''
6401 will give a longer description of the variable FOO. ``show'' will show
6402 all of the variable descriptions and their current settings.
6404 confirm on/off: Enables warning questions for operations that are
6405 hard to recover from, e.g. rerunning the program while
6406 it is already running. Default is ON.
6408 editing on/off: Enables EMACS style command line editing
6409 of input. Previous lines can be recalled with
6410 control-P, the current line can be edited with control-B,
6411 you can search for commands with control-R, etc.
6414 history filename NAME: NAME is where the gdb command history
6415 will be stored. The default is .gdb_history,
6416 or the value of the environment variable
6419 history size N: The size, in commands, of the command history. The
6420 default is 256, or the value of the environment variable
6423 history save on/off: If this value is set to ON, the history file will
6424 be saved after exiting gdb. If set to OFF, the
6425 file will not be saved. The default is OFF.
6427 history expansion on/off: If this value is set to ON, then csh-like
6428 history expansion will be performed on
6429 command line input. The default is OFF.
6431 radix N: Sets the default radix for input and output. It can be set
6432 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6433 in the current radix, so "set radix 10" is always a no-op.
6435 height N: This integer value is the number of lines on a page. Default
6436 is 24, the current `stty rows'' setting, or the ``li#''
6437 setting from the termcap entry matching the environment
6440 width N: This integer value is the number of characters on a line.
6441 Default is 80, the current `stty cols'' setting, or the ``co#''
6442 setting from the termcap entry matching the environment
6445 Note: ``set screensize'' is obsolete. Use ``set height'' and
6446 ``set width'' instead.
6448 print address on/off: Print memory addresses in various command displays,
6449 such as stack traces and structure values. Gdb looks
6450 more ``symbolic'' if you turn this off; it looks more
6451 ``machine level'' with it on. Default is ON.
6453 print array on/off: Prettyprint arrays. New convenient format! Default
6456 print demangle on/off: Print C++ symbols in "source" form if on,
6459 print asm-demangle on/off: Same, for assembler level printouts
6462 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6465 * Support for Epoch Environment.
6467 The epoch environment is a version of Emacs v18 with windowing. One
6468 new command, ``inspect'', is identical to ``print'', except that if you
6469 are running in the epoch environment, the value is printed in its own
6473 * Support for Shared Libraries
6475 GDB can now debug programs and core files that use SunOS shared libraries.
6476 Symbols from a shared library cannot be referenced
6477 before the shared library has been linked with the program (this
6478 happens after you type ``run'' and before the function main() is entered).
6479 At any time after this linking (including when examining core files
6480 from dynamically linked programs), gdb reads the symbols from each
6481 shared library when you type the ``sharedlibrary'' command.
6482 It can be abbreviated ``share''.
6484 sharedlibrary REGEXP: Load shared object library symbols for files
6485 matching a unix regular expression. No argument
6486 indicates to load symbols for all shared libraries.
6488 info sharedlibrary: Status of loaded shared libraries.
6493 A watchpoint stops execution of a program whenever the value of an
6494 expression changes. Checking for this slows down execution
6495 tremendously whenever you are in the scope of the expression, but is
6496 quite useful for catching tough ``bit-spreader'' or pointer misuse
6497 problems. Some machines such as the 386 have hardware for doing this
6498 more quickly, and future versions of gdb will use this hardware.
6500 watch EXP: Set a watchpoint (breakpoint) for an expression.
6502 info watchpoints: Information about your watchpoints.
6504 delete N: Deletes watchpoint number N (same as breakpoints).
6505 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6506 enable N: Re-enables watchpoint number N (same as breakpoints).
6509 * C++ multiple inheritance
6511 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6514 * C++ exception handling
6516 Gdb now supports limited C++ exception handling. Besides the existing
6517 ability to breakpoint on an exception handler, gdb can breakpoint on
6518 the raising of an exception (before the stack is peeled back to the
6521 catch FOO: If there is a FOO exception handler in the dynamic scope,
6522 set a breakpoint to catch exceptions which may be raised there.
6523 Multiple exceptions (``catch foo bar baz'') may be caught.
6525 info catch: Lists all exceptions which may be caught in the
6526 current stack frame.
6529 * Minor command changes
6531 The command ``call func (arg, arg, ...)'' now acts like the print
6532 command, except it does not print or save a value if the function's result
6533 is void. This is similar to dbx usage.
6535 The ``up'' and ``down'' commands now always print the frame they end up
6536 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6537 frames without printing.
6539 * New directory command
6541 'dir' now adds directories to the FRONT of the source search path.
6542 The path starts off empty. Source files that contain debug information
6543 about the directory in which they were compiled can be found even
6544 with an empty path; Sun CC and GCC include this information. If GDB can't
6545 find your source file in the current directory, type "dir .".
6547 * Configuring GDB for compilation
6549 For normal use, type ``./configure host''. See README or gdb.texinfo
6552 GDB now handles cross debugging. If you are remotely debugging between
6553 two different machines, type ``./configure host -target=targ''.
6554 Host is the machine where GDB will run; targ is the machine
6555 where the program that you are debugging will run.
projects / external / binutils.git / blob