1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.12
6 * Building GDB and GDBserver now requires a C++11 compiler.
8 For example, GCC 4.8 or later.
10 It is no longer possible to build GDB or GDBserver with a C
11 compiler. The --disable-build-with-cxx configure option has been
14 * Building GDB and GDBserver now requires GNU make >= 3.81.
16 It is no longer supported to build GDB or GDBserver with another
17 implementation of the make program or an earlier version of GNU make.
19 * Native debugging on MS-Windows supports command-line redirection
21 Command-line arguments used for starting programs on MS-Windows can
22 now include redirection symbols supported by native Windows shells,
23 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
24 as "run", "start", and "set args", as well as the corresponding MI
27 * Support for thread names on MS-Windows.
29 GDB now catches and handles the special exception that programs
30 running on MS-Windows use to assign names to threads in the
33 * Support for Java programs compiled with gcj has been removed.
35 * The "eval" command now expands user-defined command arguments.
37 This makes it easier to process a variable number of arguments:
42 eval "print $arg%d", $i
49 Synopsys ARC arc*-*-elf32
51 *** Changes in GDB 7.12
53 * GDB and GDBserver now build with a C++ compiler by default.
55 The --enable-build-with-cxx configure option is now enabled by
56 default. One must now explicitly configure with
57 --disable-build-with-cxx in order to build with a C compiler. This
58 option will be removed in a future release.
60 * GDBserver now supports recording btrace without maintaining an active
63 * GDB now supports a negative repeat count in the 'x' command to examine
64 memory backward from the given address. For example:
67 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
68 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
69 (gdb) x/-5i 0x0000000000400580
70 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
71 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
72 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
73 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
74 0x40057b <main(int, char**)+25>:
75 callq 0x400536 <Func1(int, char const*)>
77 * Fortran: Support structures with fields of dynamic types and
78 arrays of dynamic types.
80 * GDB now supports multibit bitfields and enums in target register
83 * New Python-based convenience function $_as_string(val), which returns
84 the textual representation of a value. This function is especially
85 useful to obtain the text label of an enum value.
87 * Intel MPX bound violation handling.
89 Segmentation faults caused by a Intel MPX boundary violation
90 now display the kind of violation (upper or lower), the memory
91 address accessed and the memory bounds, along with the usual
92 signal received and code location.
96 Program received signal SIGSEGV, Segmentation fault
97 Upper bound violation while accessing address 0x7fffffffc3b3
98 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
99 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
101 * Rust language support.
102 GDB now supports debugging programs written in the Rust programming
103 language. See https://www.rust-lang.org/ for more information about
106 * Support for running interpreters on specified input/output devices
108 GDB now supports a new mechanism that allows frontends to provide
109 fully featured GDB console views, as a better alternative to
110 building such views on top of the "-interpreter-exec console"
111 command. See the new "new-ui" command below. With that command,
112 frontends can now start GDB in the traditional command-line mode
113 running in an embedded terminal emulator widget, and create a
114 separate MI interpreter running on a specified i/o device. In this
115 way, GDB handles line editing, history, tab completion, etc. in the
116 console all by itself, and the GUI uses the separate MI interpreter
117 for its own control and synchronization, invisible to the command
120 * The "catch syscall" command catches groups of related syscalls.
122 The "catch syscall" command now supports catching a group of related
123 syscalls using the 'group:' or 'g:' prefix.
128 skip -gfile file-glob-pattern
129 skip -function function
130 skip -rfunction regular-expression
131 A generalized form of the skip command, with new support for
132 glob-style file names and regular expressions for function names.
133 Additionally, a file spec and a function spec may now be combined.
135 maint info line-table REGEXP
136 Display the contents of GDB's internal line table data struture.
139 Run any GDB unit tests that were compiled in.
142 Start a new user interface instance running INTERP as interpreter,
143 using the TTY file for input/output.
147 ** gdb.Breakpoint objects have a new attribute "pending", which
148 indicates whether the breakpoint is pending.
149 ** Three new breakpoint-related events have been added:
150 gdb.breakpoint_created, gdb.breakpoint_modified, and
151 gdb.breakpoint_deleted.
154 Signal ("set") the given MS-Windows event object. This is used in
155 conjunction with the Windows JIT debugging (AeDebug) support, where
156 the OS suspends a crashing process until a debugger can attach to
157 it. Resuming the crashing process, in order to debug it, is done by
160 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
161 was added in GDBserver, including JIT compiling fast tracepoint's
162 conditional expression bytecode into native code.
164 * Support for various remote target protocols and ROM monitors has
167 target m32rsdi Remote M32R debugging over SDI
168 target mips MIPS remote debugging protocol
169 target pmon PMON ROM monitor
170 target ddb NEC's DDB variant of PMON for Vr4300
171 target rockhopper NEC RockHopper variant of PMON
172 target lsi LSI variant of PMO
174 * Support for tracepoints and fast tracepoints on powerpc-linux,
175 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
176 including JIT compiling fast tracepoint's conditional expression
177 bytecode into native code.
179 * MI async record =record-started now includes the method and format used for
180 recording. For example:
182 =record-started,thread-group="i1",method="btrace",format="bts"
184 * MI async record =thread-selected now includes the frame field. For example:
186 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
190 Andes NDS32 nds32*-*-elf
192 *** Changes in GDB 7.11
194 * GDB now supports debugging kernel-based threads on FreeBSD.
196 * Per-inferior thread numbers
198 Thread numbers are now per inferior instead of global. If you're
199 debugging multiple inferiors, GDB displays thread IDs using a
200 qualified INF_NUM.THR_NUM form. For example:
204 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
205 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
206 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
207 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
209 As consequence, thread numbers as visible in the $_thread
210 convenience variable and in Python's InferiorThread.num attribute
211 are no longer unique between inferiors.
213 GDB now maintains a second thread ID per thread, referred to as the
214 global thread ID, which is the new equivalent of thread numbers in
215 previous releases. See also $_gthread below.
217 For backwards compatibility, MI's thread IDs always refer to global
220 * Commands that accept thread IDs now accept the qualified
221 INF_NUM.THR_NUM form as well. For example:
224 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
227 * In commands that accept a list of thread IDs, you can now refer to
228 all threads of an inferior using a star wildcard. GDB accepts
229 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
230 refer to all threads of the current inferior. For example, "info
233 * You can use "info threads -gid" to display the global thread ID of
236 * The new convenience variable $_gthread holds the global number of
239 * The new convenience variable $_inferior holds the number of the
242 * GDB now displays the ID and name of the thread that hit a breakpoint
243 or received a signal, if your program is multi-threaded. For
246 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
247 Thread 1 "main" received signal SIGINT, Interrupt.
249 * Record btrace now supports non-stop mode.
251 * Support for tracepoints on aarch64-linux was added in GDBserver.
253 * The 'record instruction-history' command now indicates speculative execution
254 when using the Intel Processor Trace recording format.
256 * GDB now allows users to specify explicit locations, bypassing
257 the linespec parser. This feature is also available to GDB/MI
260 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
261 GDB now is able to debug both AArch64 applications and ARM applications
264 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
265 including JIT compiling fast tracepoint's conditional expression bytecode
268 * GDB now supports displaced stepping on AArch64 GNU/Linux.
270 * "info threads", "info inferiors", "info display", "info checkpoints"
271 and "maint info program-spaces" now list the corresponding items in
272 ascending ID order, for consistency with all other "info" commands.
274 * In Ada, the overloads selection menu has been enhanced to display the
275 parameter types and the return types for the matching overloaded subprograms.
279 maint set target-non-stop (on|off|auto)
280 maint show target-non-stop
281 Control whether GDB targets always operate in non-stop mode even if
282 "set non-stop" is "off". The default is "auto", meaning non-stop
283 mode is enabled if supported by the target.
285 maint set bfd-sharing
286 maint show bfd-sharing
287 Control the reuse of bfd objects.
291 Control display of debugging info regarding bfd caching.
295 Control display of debugging info regarding FreeBSD threads.
297 set remote multiprocess-extensions-packet
298 show remote multiprocess-extensions-packet
299 Set/show the use of the remote protocol multiprocess extensions.
301 set remote thread-events
302 show remote thread-events
303 Set/show the use of thread create/exit events.
305 set ada print-signatures on|off
306 show ada print-signatures"
307 Control whether parameter types and return types are displayed in overloads
308 selection menus. It is activaled (@code{on}) by default.
312 Controls the maximum size of memory, in bytes, that GDB will
313 allocate for value contents. Prevents incorrect programs from
314 causing GDB to allocate overly large buffers. Default is 64k.
316 * The "disassemble" command accepts a new modifier: /s.
317 It prints mixed source+disassembly like /m with two differences:
318 - disassembled instructions are now printed in program order, and
319 - and source for all relevant files is now printed.
320 The "/m" option is now considered deprecated: its "source-centric"
321 output hasn't proved useful in practice.
323 * The "record instruction-history" command accepts a new modifier: /s.
324 It behaves exactly like /m and prints mixed source+disassembly.
326 * The "set scheduler-locking" command supports a new mode "replay".
327 It behaves like "off" in record mode and like "on" in replay mode.
329 * Support for various ROM monitors has been removed:
331 target dbug dBUG ROM monitor for Motorola ColdFire
332 target picobug Motorola picobug monitor
333 target dink32 DINK32 ROM monitor for PowerPC
334 target m32r Renesas M32R/D ROM monitor
335 target mon2000 mon2000 ROM monitor
336 target ppcbug PPCBUG ROM monitor for PowerPC
338 * Support for reading/writing memory and extracting values on architectures
339 whose memory is addressable in units of any integral multiple of 8 bits.
344 Indicates that an exec system call was executed.
346 exec-events feature in qSupported
347 The qSupported packet allows GDB to request support for exec
348 events using the new 'gdbfeature' exec-event, and the qSupported
349 response can contain the corresponding 'stubfeature'. Set and
350 show commands can be used to display whether these features are enabled.
353 Equivalent to interrupting with the ^C character, but works in
356 thread created stop reason (T05 create:...)
357 Indicates that the thread was just created and is stopped at entry.
359 thread exit stop reply (w exitcode;tid)
360 Indicates that the thread has terminated.
363 Enables/disables thread create and exit event reporting. For
364 example, this is used in non-stop mode when GDB stops a set of
365 threads and synchronously waits for the their corresponding stop
366 replies. Without exit events, if one of the threads exits, GDB
367 would hang forever not knowing that it should no longer expect a
368 stop for that same thread.
371 Indicates that there are no resumed threads left in the target (all
372 threads are stopped). The remote stub reports support for this stop
373 reply to GDB's qSupported query.
376 Enables/disables catching syscalls from the inferior process.
377 The remote stub reports support for this packet to GDB's qSupported query.
379 syscall_entry stop reason
380 Indicates that a syscall was just called.
382 syscall_return stop reason
383 Indicates that a syscall just returned.
385 * Extended-remote exec events
387 ** GDB now has support for exec events on extended-remote Linux targets.
388 For such targets with Linux kernels 2.5.46 and later, this enables
389 follow-exec-mode and exec catchpoints.
391 set remote exec-event-feature-packet
392 show remote exec-event-feature-packet
393 Set/show the use of the remote exec event feature.
395 * Thread names in remote protocol
397 The reply to qXfer:threads:read may now include a name attribute for each
400 * Target remote mode fork and exec events
402 ** GDB now has support for fork and exec events on target remote mode
403 Linux targets. For such targets with Linux kernels 2.5.46 and later,
404 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
405 fork and exec catchpoints.
407 * Remote syscall events
409 ** GDB now has support for catch syscall on remote Linux targets,
410 currently enabled on x86/x86_64 architectures.
412 set remote catch-syscall-packet
413 show remote catch-syscall-packet
414 Set/show the use of the remote catch syscall feature.
418 ** The -var-set-format command now accepts the zero-hexadecimal
419 format. It outputs data in hexadecimal format with zero-padding on the
424 ** gdb.InferiorThread objects have a new attribute "global_num",
425 which refers to the thread's global thread ID. The existing
426 "num" attribute now refers to the thread's per-inferior number.
427 See "Per-inferior thread numbers" above.
428 ** gdb.InferiorThread objects have a new attribute "inferior", which
429 is the Inferior object the thread belongs to.
431 *** Changes in GDB 7.10
433 * Support for process record-replay and reverse debugging on aarch64*-linux*
434 targets has been added. GDB now supports recording of A64 instruction set
435 including advance SIMD instructions.
437 * Support for Sun's version of the "stabs" debug file format has been removed.
439 * GDB now honors the content of the file /proc/PID/coredump_filter
440 (PID is the process ID) on GNU/Linux systems. This file can be used
441 to specify the types of memory mappings that will be included in a
442 corefile. For more information, please refer to the manual page of
443 "core(5)". GDB also has a new command: "set use-coredump-filter
444 on|off". It allows to set whether GDB will read the content of the
445 /proc/PID/coredump_filter file when generating a corefile.
447 * The "info os" command on GNU/Linux can now display information on
449 "info os cpus" Listing of all cpus/cores on the system
451 * GDB has two new commands: "set serial parity odd|even|none" and
452 "show serial parity". These allows to set or show parity for the
455 * The "info source" command now displays the producer string if it was
456 present in the debug info. This typically includes the compiler version
457 and may include things like its command line arguments.
459 * The "info dll", an alias of the "info sharedlibrary" command,
460 is now available on all platforms.
462 * Directory names supplied to the "set sysroot" commands may be
463 prefixed with "target:" to tell GDB to access shared libraries from
464 the target system, be it local or remote. This replaces the prefix
465 "remote:". The default sysroot has been changed from "" to
466 "target:". "remote:" is automatically converted to "target:" for
467 backward compatibility.
469 * The system root specified by "set sysroot" will be prepended to the
470 filename of the main executable (if reported to GDB as absolute by
471 the operating system) when starting processes remotely, and when
472 attaching to already-running local or remote processes.
474 * GDB now supports automatic location and retrieval of executable
475 files from remote targets. Remote debugging can now be initiated
476 using only a "target remote" or "target extended-remote" command
477 (no "set sysroot" or "file" commands are required). See "New remote
480 * The "dump" command now supports verilog hex format.
482 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
484 * On GNU/Linux, GDB and gdbserver are now able to access executable
485 and shared library files without a "set sysroot" command when
486 attaching to processes running in different mount namespaces from
487 the debugger. This makes it possible to attach to processes in
488 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
489 See "New remote packets" below.
491 * The "tui reg" command now provides completion for all of the
492 available register groups, including target specific groups.
494 * The HISTSIZE environment variable is no longer read when determining
495 the size of GDB's command history. GDB now instead reads the dedicated
496 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
497 disables truncation of command history. Non-numeric values of GDBHISTSIZE
502 ** Memory ports can now be unbuffered.
506 ** gdb.Objfile objects have a new attribute "username",
507 which is the name of the objfile as specified by the user,
508 without, for example, resolving symlinks.
509 ** You can now write frame unwinders in Python.
510 ** gdb.Type objects have a new method "optimized_out",
511 returning optimized out gdb.Value instance of this type.
512 ** gdb.Value objects have new methods "reference_value" and
513 "const_value" which return a reference to the value and a
514 "const" version of the value respectively.
518 maint print symbol-cache
519 Print the contents of the symbol cache.
521 maint print symbol-cache-statistics
522 Print statistics of symbol cache usage.
524 maint flush-symbol-cache
525 Flush the contents of the symbol cache.
529 Start branch trace recording using Branch Trace Store (BTS) format.
532 Evaluate expression by using the compiler and print result.
536 Explicit commands for enabling and disabling tui mode.
539 set mpx bound on i386 and amd64
540 Support for bound table investigation on Intel MPX enabled applications.
544 Start branch trace recording using Intel Processor Trace format.
547 Print information about branch tracing internals.
549 maint btrace packet-history
550 Print the raw branch tracing data.
552 maint btrace clear-packet-history
553 Discard the stored raw branch tracing data.
556 Discard all branch tracing data. It will be fetched and processed
557 anew by the next "record" command.
562 Renamed from "set debug dwarf2-die".
564 Renamed from "show debug dwarf2-die".
567 Renamed from "set debug dwarf2-read".
568 show debug dwarf-read
569 Renamed from "show debug dwarf2-read".
571 maint set dwarf always-disassemble
572 Renamed from "maint set dwarf2 always-disassemble".
573 maint show dwarf always-disassemble
574 Renamed from "maint show dwarf2 always-disassemble".
576 maint set dwarf max-cache-age
577 Renamed from "maint set dwarf2 max-cache-age".
578 maint show dwarf max-cache-age
579 Renamed from "maint show dwarf2 max-cache-age".
582 show debug dwarf-line
583 Control display of debugging info regarding DWARF line processing.
587 Set the maximum number of candidates to be considered during
588 completion. The default value is 200. This limit allows GDB
589 to avoid generating large completion lists, the computation of
590 which can cause the debugger to become temporarily unresponsive.
592 set history remove-duplicates
593 show history remove-duplicates
594 Control the removal of duplicate history entries.
596 maint set symbol-cache-size
597 maint show symbol-cache-size
598 Control the size of the symbol cache.
600 set|show record btrace bts buffer-size
601 Set and show the size of the ring buffer used for branch tracing in
603 The obtained size may differ from the requested size. Use "info
604 record" to see the obtained buffer size.
606 set debug linux-namespaces
607 show debug linux-namespaces
608 Control display of debugging info regarding Linux namespaces.
610 set|show record btrace pt buffer-size
611 Set and show the size of the ring buffer used for branch tracing in
612 Intel Processor Trace format.
613 The obtained size may differ from the requested size. Use "info
614 record" to see the obtained buffer size.
616 maint set|show btrace pt skip-pad
617 Set and show whether PAD packets are skipped when computing the
620 * The command 'thread apply all' can now support new option '-ascending'
621 to call its specified command for all threads in ascending order.
623 * Python/Guile scripting
625 ** GDB now supports auto-loading of Python/Guile scripts contained in the
626 special section named `.debug_gdb_scripts'.
630 qXfer:btrace-conf:read
631 Return the branch trace configuration for the current thread.
633 Qbtrace-conf:bts:size
634 Set the requested ring buffer size for branch tracing in BTS format.
637 Enable Intel Procesor Trace-based branch tracing for the current
638 process. The remote stub reports support for this packet to GDB's
642 Set the requested ring buffer size for branch tracing in Intel Processor
646 Indicates a memory breakpoint instruction was executed, irrespective
647 of whether it was GDB that planted the breakpoint or the breakpoint
648 is hardcoded in the program. This is required for correct non-stop
652 Indicates the target stopped for a hardware breakpoint. This is
653 required for correct non-stop mode operation.
656 Return information about files on the remote system.
659 Return the full absolute name of the file that was executed to
660 create a process running on the remote system.
663 Select the filesystem on which vFile: operations with filename
664 arguments will operate. This is required for GDB to be able to
665 access files on remote targets where the remote stub does not
666 share a common filesystem with the inferior(s).
669 Indicates that a fork system call was executed.
672 Indicates that a vfork system call was executed.
674 vforkdone stop reason
675 Indicates that a vfork child of the specified process has executed
676 an exec or exit, allowing the vfork parent to resume execution.
678 fork-events and vfork-events features in qSupported
679 The qSupported packet allows GDB to request support for fork and
680 vfork events using new 'gdbfeatures' fork-events and vfork-events,
681 and the qSupported response can contain the corresponding
682 'stubfeatures'. Set and show commands can be used to display
683 whether these features are enabled.
685 * Extended-remote fork events
687 ** GDB now has support for fork events on extended-remote Linux
688 targets. For targets with Linux kernels 2.5.60 and later, this
689 enables follow-fork-mode and detach-on-fork for both fork and
690 vfork, as well as fork and vfork catchpoints.
692 * The info record command now shows the recording format and the
693 branch tracing configuration for the current thread when using
694 the btrace record target.
695 For the BTS format, it shows the ring buffer size.
697 * GDB now has support for DTrace USDT (Userland Static Defined
698 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
700 * GDB now supports access to vector registers on S/390 GNU/Linux
703 * Removed command line options
705 -xdb HP-UX XDB compatibility mode.
707 * Removed targets and native configurations
709 HP/PA running HP-UX hppa*-*-hpux*
710 Itanium running HP-UX ia64-*-hpux*
712 * New configure options
715 This configure option allows the user to build GDB with support for
716 Intel Processor Trace (default: auto). This requires libipt.
718 --with-libipt-prefix=PATH
719 Specify the path to the version of libipt that GDB should use.
720 $PATH/include should contain the intel-pt.h header and
721 $PATH/lib should contain the libipt.so library.
723 *** Changes in GDB 7.9.1
727 ** Xmethods can now specify a result type.
729 *** Changes in GDB 7.9
731 * GDB now supports hardware watchpoints on x86 GNU Hurd.
735 ** You can now access frame registers from Python scripts.
736 ** New attribute 'producer' for gdb.Symtab objects.
737 ** gdb.Objfile objects have a new attribute "progspace",
738 which is the gdb.Progspace object of the containing program space.
739 ** gdb.Objfile objects have a new attribute "owner".
740 ** gdb.Objfile objects have a new attribute "build_id",
741 which is the build ID generated when the file was built.
742 ** gdb.Objfile objects have a new method "add_separate_debug_file".
743 ** A new event "gdb.clear_objfiles" has been added, triggered when
744 selecting a new file to debug.
745 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
746 ** New function gdb.lookup_objfile.
748 New events which are triggered when GDB modifies the state of the
751 ** gdb.events.inferior_call_pre: Function call is about to be made.
752 ** gdb.events.inferior_call_post: Function call has just been made.
753 ** gdb.events.memory_changed: A memory location has been altered.
754 ** gdb.events.register_changed: A register has been altered.
756 * New Python-based convenience functions:
758 ** $_caller_is(name [, number_of_frames])
759 ** $_caller_matches(regexp [, number_of_frames])
760 ** $_any_caller_is(name [, number_of_frames])
761 ** $_any_caller_matches(regexp [, number_of_frames])
763 * GDB now supports the compilation and injection of source code into
764 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
765 to compile the source code to object code, and if successful, inject
766 and execute that code within the current context of the inferior.
767 Currently the C language is supported. The commands used to
768 interface with this new feature are:
770 compile code [-raw|-r] [--] [source code]
771 compile file [-raw|-r] filename
775 demangle [-l language] [--] name
776 Demangle "name" in the specified language, or the current language
777 if elided. This command is renamed from the "maint demangle" command.
778 The latter is kept as a no-op to avoid "maint demangle" being interpreted
779 as "maint demangler-warning".
781 queue-signal signal-name-or-number
782 Queue a signal to be delivered to the thread when it is resumed.
784 add-auto-load-scripts-directory directory
785 Add entries to the list of directories from which to load auto-loaded
788 maint print user-registers
789 List all currently available "user" registers.
791 compile code [-r|-raw] [--] [source code]
792 Compile, inject, and execute in the inferior the executable object
793 code produced by compiling the provided source code.
795 compile file [-r|-raw] filename
796 Compile and inject into the inferior the executable object code
797 produced by compiling the source code stored in the filename
800 * On resume, GDB now always passes the signal the program had stopped
801 for to the thread the signal was sent to, even if the user changed
802 threads before resuming. Previously GDB would often (but not
803 always) deliver the signal to the thread that happens to be current
806 * Conversely, the "signal" command now consistently delivers the
807 requested signal to the current thread. GDB now asks for
808 confirmation if the program had stopped for a signal and the user
809 switched threads meanwhile.
811 * "breakpoint always-inserted" modes "off" and "auto" merged.
813 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
814 won't remove breakpoints from the target until all threads stop,
815 even in non-stop mode. The "auto" mode has been removed, and "off"
816 is now the default mode.
820 set debug symbol-lookup
821 show debug symbol-lookup
822 Control display of debugging info regarding symbol lookup.
826 ** The -list-thread-groups command outputs an exit-code field for
827 inferiors that have exited.
831 MIPS SDE mips*-sde*-elf*
835 Support for these obsolete configurations has been removed.
837 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
838 SGI Irix-5.x mips-*-irix5*
839 SGI Irix-6.x mips-*-irix6*
840 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
841 VAX running Ultrix vax-*-ultrix*
843 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
844 and "assf"), have been removed. Use the "sharedlibrary" command, or
845 its alias "share", instead.
847 *** Changes in GDB 7.8
849 * New command line options
852 This is an alias for the --data-directory option.
854 * GDB supports printing and modifying of variable length automatic arrays
855 as specified in ISO C99.
857 * The ARM simulator now supports instruction level tracing
858 with or without disassembly.
862 GDB now has support for scripting using Guile. Whether this is
863 available is determined at configure time.
864 Guile version 2.0 or greater is required.
865 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
867 * New commands (for set/show, see "New options" below)
871 Invoke CODE by passing it to the Guile interpreter.
875 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
877 info auto-load guile-scripts [regexp]
878 Print the list of automatically loaded Guile scripts.
880 * The source command is now capable of sourcing Guile scripts.
881 This feature is dependent on the debugger being built with Guile support.
885 set print symbol-loading (off|brief|full)
886 show print symbol-loading
887 Control whether to print informational messages when loading symbol
888 information for a file. The default is "full", but when debugging
889 programs with large numbers of shared libraries the amount of output
892 set guile print-stack (none|message|full)
893 show guile print-stack
894 Show a stack trace when an error is encountered in a Guile script.
896 set auto-load guile-scripts (on|off)
897 show auto-load guile-scripts
898 Control auto-loading of Guile script files.
900 maint ada set ignore-descriptive-types (on|off)
901 maint ada show ignore-descriptive-types
902 Control whether the debugger should ignore descriptive types in Ada
903 programs. The default is not to ignore the descriptive types. See
904 the user manual for more details on descriptive types and the intended
905 usage of this option.
907 set auto-connect-native-target
909 Control whether GDB is allowed to automatically connect to the
910 native target for the run, attach, etc. commands when not connected
911 to any target yet. See also "target native" below.
913 set record btrace replay-memory-access (read-only|read-write)
914 show record btrace replay-memory-access
915 Control what memory accesses are allowed during replay.
917 maint set target-async (on|off)
918 maint show target-async
919 This controls whether GDB targets operate in synchronous or
920 asynchronous mode. Normally the default is asynchronous, if it is
921 available; but this can be changed to more easily debug problems
922 occurring only in synchronous mode.
924 set mi-async (on|off)
926 Control whether MI asynchronous mode is preferred. This supersedes
927 "set target-async" of previous GDB versions.
929 * "set target-async" is deprecated as a CLI option and is now an alias
930 for "set mi-async" (only puts MI into async mode).
932 * Background execution commands (e.g., "c&", "s&", etc.) are now
933 possible ``out of the box'' if the target supports them. Previously
934 the user would need to explicitly enable the possibility with the
935 "set target-async on" command.
937 * New features in the GDB remote stub, GDBserver
939 ** New option --debug-format=option1[,option2,...] allows one to add
940 additional text to each output. At present only timestamps
941 are supported: --debug-format=timestamps.
942 Timestamps can also be turned on with the
943 "monitor set debug-format timestamps" command from GDB.
945 * The 'record instruction-history' command now starts counting instructions
946 at one. This also affects the instruction ranges reported by the
947 'record function-call-history' command when given the /i modifier.
949 * The command 'record function-call-history' supports a new modifier '/c' to
950 indent the function names based on their call stack depth.
951 The fields for the '/i' and '/l' modifier have been reordered.
952 The source line range is now prefixed with 'at'.
953 The instruction range is now prefixed with 'inst'.
954 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
955 "record instruction-history" and "list" commands.
957 * The ranges given as arguments to the 'record function-call-history' and
958 'record instruction-history' commands are now inclusive.
960 * The btrace record target now supports the 'record goto' command.
961 For locations inside the execution trace, the back trace is computed
962 based on the information stored in the execution trace.
964 * The btrace record target supports limited reverse execution and replay.
965 The target does not record data and therefore does not allow reading
968 * The "catch syscall" command now works on s390*-linux* targets.
970 * The "compare-sections" command is no longer specific to target
971 remote. It now works with all targets.
973 * All native targets are now consistently called "native".
974 Consequently, the "target child", "target GNU", "target djgpp",
975 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
976 commands have been replaced with "target native". The QNX/NTO port
977 leaves the "procfs" target in place and adds a "native" target for
978 consistency with other ports. The impact on users should be minimal
979 as these commands previously either throwed an error, or were
980 no-ops. The target's name is visible in the output of the following
981 commands: "help target", "info target", "info files", "maint print
984 * The "target native" command now connects to the native target. This
985 can be used to launch native programs even when "set
986 auto-connect-native-target" is set to off.
988 * GDB now supports access to Intel MPX registers on GNU/Linux.
990 * Support for Intel AVX-512 registers on GNU/Linux.
991 Support displaying and modifying Intel AVX-512 registers
992 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
996 qXfer:btrace:read's annex
997 The qXfer:btrace:read packet supports a new annex 'delta' to read
998 branch trace incrementally.
1002 ** Valid Python operations on gdb.Value objects representing
1003 structs/classes invoke the corresponding overloaded operators if
1005 ** New `Xmethods' feature in the Python API. Xmethods are
1006 additional methods or replacements for existing methods of a C++
1007 class. This feature is useful for those cases where a method
1008 defined in C++ source code could be inlined or optimized out by
1009 the compiler, making it unavailable to GDB.
1012 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1014 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1015 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1016 its alias "share", instead.
1018 * The commands "set remotebaud" and "show remotebaud" are no longer
1019 supported. Use "set serial baud" and "show serial baud" (respectively)
1024 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1025 target-async". The latter is left as a deprecated alias of the
1026 former for backward compatibility. If the target supports it,
1027 CLI background execution commands are now always possible by
1028 default, independently of whether the frontend stated a
1029 preference for asynchronous execution with "-gdb-set mi-async".
1030 Previously "-gdb-set target-async off" affected both MI execution
1031 commands and CLI execution commands.
1033 *** Changes in GDB 7.7
1035 * Improved support for process record-replay and reverse debugging on
1036 arm*-linux* targets. Support for thumb32 and syscall instruction
1037 recording has been added.
1039 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1041 * GDB now supports Fission DWP file format version 2.
1042 http://gcc.gnu.org/wiki/DebugFission
1044 * New convenience function "$_isvoid", to check whether an expression
1045 is void. A void expression is an expression where the type of the
1046 result is "void". For example, some convenience variables may be
1047 "void" when evaluated (e.g., "$_exitcode" before the execution of
1048 the program being debugged; or an undefined convenience variable).
1049 Another example, when calling a function whose return type is
1052 * The "maintenance print objfiles" command now takes an optional regexp.
1054 * The "catch syscall" command now works on arm*-linux* targets.
1056 * GDB now consistently shows "<not saved>" when printing values of
1057 registers the debug info indicates have not been saved in the frame
1058 and there's nowhere to retrieve them from
1059 (callee-saved/call-clobbered registers):
1064 (gdb) info registers rax
1067 Before, the former would print "<optimized out>", and the latter
1068 "*value not available*".
1070 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1075 ** Frame filters and frame decorators have been added.
1076 ** Temporary breakpoints are now supported.
1077 ** Line tables representation has been added.
1078 ** New attribute 'parent_type' for gdb.Field objects.
1079 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1080 ** New attribute 'name' for gdb.Type objects.
1084 Nios II ELF nios2*-*-elf
1085 Nios II GNU/Linux nios2*-*-linux
1086 Texas Instruments MSP430 msp430*-*-elf
1088 * Removed native configurations
1090 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1091 been removed. ELF variants of these configurations are kept supported.
1093 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1094 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1095 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1096 i[34567]86-*-openbsd3.[0-3]
1097 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1098 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1099 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1103 Like "catch throw", but catches a re-thrown exception.
1104 maint check-psymtabs
1105 Renamed from old "maint check-symtabs".
1107 Perform consistency checks on symtabs.
1108 maint expand-symtabs
1109 Expand symtabs matching an optional regexp.
1112 Display the details of GDB configure-time options.
1114 maint set|show per-command
1115 maint set|show per-command space
1116 maint set|show per-command time
1117 maint set|show per-command symtab
1118 Enable display of per-command gdb resource usage.
1120 remove-symbol-file FILENAME
1121 remove-symbol-file -a ADDRESS
1122 Remove a symbol file added via add-symbol-file. The file to remove
1123 can be identified by its filename or by an address that lies within
1124 the boundaries of this symbol file in memory.
1127 info exceptions REGEXP
1128 Display the list of Ada exceptions defined in the program being
1129 debugged. If provided, only the exceptions whose names match REGEXP
1134 set debug symfile off|on
1136 Control display of debugging info regarding reading symbol files and
1137 symbol tables within those files
1139 set print raw frame-arguments
1140 show print raw frame-arguments
1141 Set/show whether to print frame arguments in raw mode,
1142 disregarding any defined pretty-printers.
1144 set remote trace-status-packet
1145 show remote trace-status-packet
1146 Set/show the use of remote protocol qTStatus packet.
1150 Control display of debugging messages related to Nios II targets.
1154 Control whether target-assisted range stepping is enabled.
1156 set startup-with-shell
1157 show startup-with-shell
1158 Specifies whether Unix child processes are started via a shell or
1163 Use the target memory cache for accesses to the code segment. This
1164 improves performance of remote debugging (particularly disassembly).
1166 * You can now use a literal value 'unlimited' for options that
1167 interpret 0 or -1 as meaning "unlimited". E.g., "set
1168 trace-buffer-size unlimited" is now an alias for "set
1169 trace-buffer-size -1" and "set height unlimited" is now an alias for
1172 * The "set debug symtab-create" debugging option of GDB has been changed to
1173 accept a verbosity level. 0 means "off", 1 provides basic debugging
1174 output, and values of 2 or greater provides more verbose output.
1176 * New command-line options
1178 Display the details of GDB configure-time options.
1180 * The command 'tsave' can now support new option '-ctf' to save trace
1181 buffer in Common Trace Format.
1183 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1186 * GDB now implements the the C++ 'typeid' operator.
1188 * The new convenience variable $_exception holds the exception being
1189 thrown or caught at an exception-related catchpoint.
1191 * The exception-related catchpoints, like "catch throw", now accept a
1192 regular expression which can be used to filter exceptions by type.
1194 * The new convenience variable $_exitsignal is automatically set to
1195 the terminating signal number when the program being debugged dies
1196 due to an uncaught signal.
1200 ** All MI commands now accept an optional "--language" option.
1201 Support for this feature can be verified by using the "-list-features"
1202 command, which should contain "language-option".
1204 ** The new command -info-gdb-mi-command allows the user to determine
1205 whether a GDB/MI command is supported or not.
1207 ** The "^error" result record returned when trying to execute an undefined
1208 GDB/MI command now provides a variable named "code" whose content is the
1209 "undefined-command" error code. Support for this feature can be verified
1210 by using the "-list-features" command, which should contain
1211 "undefined-command-error-code".
1213 ** The -trace-save MI command can optionally save trace buffer in Common
1216 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1218 ** The command -data-list-register-values now accepts an optional
1219 "--skip-unavailable" option. When used, only the available registers
1222 ** The new command -trace-frame-collected dumps collected variables,
1223 computed expressions, tvars, memory and registers in a traceframe.
1225 ** The commands -stack-list-locals, -stack-list-arguments and
1226 -stack-list-variables now accept an option "--skip-unavailable".
1227 When used, only the available locals or arguments are displayed.
1229 ** The -exec-run command now accepts an optional "--start" option.
1230 When used, the command follows the same semantics as the "start"
1231 command, stopping the program's execution at the start of its
1232 main subprogram. Support for this feature can be verified using
1233 the "-list-features" command, which should contain
1234 "exec-run-start-option".
1236 ** The new commands -catch-assert and -catch-exceptions insert
1237 catchpoints stopping the program when Ada exceptions are raised.
1239 ** The new command -info-ada-exceptions provides the equivalent of
1240 the new "info exceptions" command.
1242 * New system-wide configuration scripts
1243 A GDB installation now provides scripts suitable for use as system-wide
1244 configuration scripts for the following systems:
1248 * GDB now supports target-assigned range stepping with remote targets.
1249 This improves the performance of stepping source lines by reducing
1250 the number of control packets from/to GDB. See "New remote packets"
1253 * GDB now understands the element 'tvar' in the XML traceframe info.
1254 It has the id of the collected trace state variables.
1256 * On S/390 targets that provide the transactional-execution feature,
1257 the program interruption transaction diagnostic block (TDB) is now
1258 represented as a number of additional "registers" in GDB.
1260 * New remote packets
1264 The vCont packet supports a new 'r' action, that tells the remote
1265 stub to step through an address range itself, without GDB
1266 involvemement at each single-step.
1268 qXfer:libraries-svr4:read's annex
1269 The previously unused annex of the qXfer:libraries-svr4:read packet
1270 is now used to support passing an argument list. The remote stub
1271 reports support for this argument list to GDB's qSupported query.
1272 The defined arguments are "start" and "prev", used to reduce work
1273 necessary for library list updating, resulting in significant
1276 * New features in the GDB remote stub, GDBserver
1278 ** GDBserver now supports target-assisted range stepping. Currently
1279 enabled on x86/x86_64 GNU/Linux targets.
1281 ** GDBserver now adds element 'tvar' in the XML in the reply to
1282 'qXfer:traceframe-info:read'. It has the id of the collected
1283 trace state variables.
1285 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1288 * New 'z' formatter for printing and examining memory, this displays the
1289 value as hexadecimal zero padded on the left to the size of the type.
1291 * GDB can now use Windows x64 unwinding data.
1293 * The "set remotebaud" command has been replaced by "set serial baud".
1294 Similarly, "show remotebaud" has been replaced by "show serial baud".
1295 The "set remotebaud" and "show remotebaud" commands are still available
1296 to provide backward compatibility with older versions of GDB.
1298 *** Changes in GDB 7.6
1300 * Target record has been renamed to record-full.
1301 Record/replay is now enabled with the "record full" command.
1302 This also affects settings that are associated with full record/replay
1303 that have been moved from "set/show record" to "set/show record full":
1305 set|show record full insn-number-max
1306 set|show record full stop-at-limit
1307 set|show record full memory-query
1309 * A new record target "record-btrace" has been added. The new target
1310 uses hardware support to record the control-flow of a process. It
1311 does not support replaying the execution, but it implements the
1312 below new commands for investigating the recorded execution log.
1313 This new recording method can be enabled using:
1317 The "record-btrace" target is only available on Intel Atom processors
1318 and requires a Linux kernel 2.6.32 or later.
1320 * Two new commands have been added for record/replay to give information
1321 about the recorded execution without having to replay the execution.
1322 The commands are only supported by "record btrace".
1324 record instruction-history prints the execution history at
1325 instruction granularity
1327 record function-call-history prints the execution history at
1328 function granularity
1330 * New native configurations
1332 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1333 FreeBSD/powerpc powerpc*-*-freebsd
1334 x86_64/Cygwin x86_64-*-cygwin*
1335 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1339 ARM AArch64 aarch64*-*-elf
1340 ARM AArch64 GNU/Linux aarch64*-*-linux
1341 Lynx 178 PowerPC powerpc-*-lynx*178
1342 x86_64/Cygwin x86_64-*-cygwin*
1343 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1345 * If the configured location of system.gdbinit file (as given by the
1346 --with-system-gdbinit option at configure time) is in the
1347 data-directory (as specified by --with-gdb-datadir at configure
1348 time) or in one of its subdirectories, then GDB will look for the
1349 system-wide init file in the directory specified by the
1350 --data-directory command-line option.
1352 * New command line options:
1354 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1355 other initialization files, unlike -nx which disables all of them.
1357 * Removed command line options
1359 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1362 * The 'ptype' and 'whatis' commands now accept an argument to control
1365 * 'info proc' now works on some core files.
1369 ** Vectors can be created with gdb.Type.vector.
1371 ** Python's atexit.register now works in GDB.
1373 ** Types can be pretty-printed via a Python API.
1375 ** Python 3 is now supported (in addition to Python 2.4 or later)
1377 ** New class gdb.Architecture exposes GDB's internal representation
1378 of architecture in the Python API.
1380 ** New method Frame.architecture returns the gdb.Architecture object
1381 corresponding to the frame's architecture.
1383 * New Python-based convenience functions:
1385 ** $_memeq(buf1, buf2, length)
1386 ** $_streq(str1, str2)
1388 ** $_regex(str, regex)
1390 * The 'cd' command now defaults to using '~' (the home directory) if not
1393 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1394 default for GCC since November 2000.
1396 * The command 'forward-search' can now be abbreviated as 'fo'.
1398 * The command 'info tracepoints' can now display 'installed on target'
1399 or 'not installed on target' for each non-pending location of tracepoint.
1401 * New configure options
1403 --enable-libmcheck/--disable-libmcheck
1404 By default, development versions are built with -lmcheck on hosts
1405 that support it, in order to help track memory corruption issues.
1406 Release versions, on the other hand, are built without -lmcheck
1407 by default. The --enable-libmcheck/--disable-libmcheck configure
1408 options allow the user to override that default.
1409 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1410 This configure option allows the user to build GDB with
1411 libbabeltrace using which GDB can read Common Trace Format data.
1413 * New commands (for set/show, see "New options" below)
1416 Catch signals. This is similar to "handle", but allows commands and
1417 conditions to be attached.
1420 List the BFDs known to GDB.
1422 python-interactive [command]
1424 Start a Python interactive prompt, or evaluate the optional command
1425 and print the result of expressions.
1428 "py" is a new alias for "python".
1430 enable type-printer [name]...
1431 disable type-printer [name]...
1432 Enable or disable type printers.
1436 ** For the Renesas Super-H architecture, the "regs" command has been removed
1437 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1442 set print type methods (on|off)
1443 show print type methods
1444 Control whether method declarations are displayed by "ptype".
1445 The default is to show them.
1447 set print type typedefs (on|off)
1448 show print type typedefs
1449 Control whether typedef definitions are displayed by "ptype".
1450 The default is to show them.
1452 set filename-display basename|relative|absolute
1453 show filename-display
1454 Control the way in which filenames is displayed.
1455 The default is "relative", which preserves previous behavior.
1457 set trace-buffer-size
1458 show trace-buffer-size
1459 Request target to change the size of trace buffer.
1461 set remote trace-buffer-size-packet auto|on|off
1462 show remote trace-buffer-size-packet
1463 Control the use of the remote protocol `QTBuffer:size' packet.
1467 Control display of debugging messages related to ARM AArch64.
1470 set debug coff-pe-read
1471 show debug coff-pe-read
1472 Control display of debugging messages related to reading of COFF/PE
1477 Control display of debugging messages related to Mach-O symbols
1480 set debug notification
1481 show debug notification
1482 Control display of debugging info for async remote notification.
1486 ** Command parameter changes are now notified using new async record
1487 "=cmd-param-changed".
1488 ** Trace frame changes caused by command "tfind" are now notified using
1489 new async record "=traceframe-changed".
1490 ** The creation, deletion and modification of trace state variables
1491 are now notified using new async records "=tsv-created",
1492 "=tsv-deleted" and "=tsv-modified".
1493 ** The start and stop of process record are now notified using new
1494 async record "=record-started" and "=record-stopped".
1495 ** Memory changes are now notified using new async record
1497 ** The data-disassemble command response will include a "fullname" field
1498 containing the absolute file name when source has been requested.
1499 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1500 command, to allow pattern filling of memory areas.
1501 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1502 library load/unload events.
1503 ** The response to breakpoint commands and breakpoint async records
1504 includes an "installed" field containing a boolean state about each
1505 non-pending tracepoint location is whether installed on target or not.
1506 ** Output of the "-trace-status" command includes a "trace-file" field
1507 containing the name of the trace file being examined. This field is
1508 optional, and only present when examining a trace file.
1509 ** The "fullname" field is now always present along with the "file" field,
1510 even if the file cannot be found by GDB.
1512 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1513 You must have the LZMA library available when configuring GDB for this
1514 feature to be enabled. For more information, see:
1515 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1517 * New remote packets
1520 Set the size of trace buffer. The remote stub reports support for this
1521 packet to gdb's qSupported query.
1524 Enable Branch Trace Store (BTS)-based branch tracing for the current
1525 thread. The remote stub reports support for this packet to gdb's
1529 Disable branch tracing for the current thread. The remote stub reports
1530 support for this packet to gdb's qSupported query.
1533 Read the traced branches for the current thread. The remote stub
1534 reports support for this packet to gdb's qSupported query.
1536 *** Changes in GDB 7.5
1538 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1539 for more x32 ABI info.
1541 * GDB now supports access to MIPS DSP registers on Linux targets.
1543 * GDB now supports debugging microMIPS binaries.
1545 * The "info os" command on GNU/Linux can now display information on
1546 several new classes of objects managed by the operating system:
1547 "info os procgroups" lists process groups
1548 "info os files" lists file descriptors
1549 "info os sockets" lists internet-domain sockets
1550 "info os shm" lists shared-memory regions
1551 "info os semaphores" lists semaphores
1552 "info os msg" lists message queues
1553 "info os modules" lists loaded kernel modules
1555 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1556 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1557 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1558 options and inspect the probe arguments using the new $_probe_arg family
1559 of convenience variables. You can obtain more information about SystemTap
1560 in <http://sourceware.org/systemtap/>.
1562 * GDB now supports reversible debugging on ARM, it allows you to
1563 debug basic ARM and THUMB instructions, and provides
1564 record/replay support.
1566 * The option "symbol-reloading" has been deleted as it is no longer used.
1570 ** GDB commands implemented in Python can now be put in command class
1573 ** The "maint set python print-stack on|off" is now deleted.
1575 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1576 apply "flag enum"-style pretty-printing to any enum.
1578 ** gdb.lookup_symbol can now work when there is no current frame.
1580 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1581 the source at which the symbol was defined.
1583 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1584 method 'value'. The former indicates whether the symbol needs a
1585 frame in order to compute its value, and the latter computes the
1588 ** A new method 'referenced_value' on gdb.Value objects which can
1589 dereference pointer as well as C++ reference values.
1591 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1592 which return the global and static blocks (as gdb.Block objects),
1593 of the underlying symbol table, respectively.
1595 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1596 object associated with a PC value.
1598 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1599 of the address range occupied by code for the current source line.
1601 * Go language support.
1602 GDB now supports debugging programs written in the Go programming
1605 * GDBserver now supports stdio connections.
1606 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1608 * The binary "gdbtui" can no longer be built or installed.
1609 Use "gdb -tui" instead.
1611 * GDB will now print "flag" enums specially. A flag enum is one where
1612 all the enumerator values have no bits in common when pairwise
1613 "and"ed. When printing a value whose type is a flag enum, GDB will
1614 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1615 (gdb) print (enum E) 3
1618 * The filename part of a linespec will now match trailing components
1619 of a source file name. For example, "break gcc/expr.c:1000" will
1620 now set a breakpoint in build/gcc/expr.c, but not
1621 build/libcpp/expr.c.
1623 * The "info proc" and "generate-core-file" commands will now also
1624 work on remote targets connected to GDBserver on Linux.
1626 * The command "info catch" has been removed. It has been disabled
1627 since December 2007.
1629 * The "catch exception" and "catch assert" commands now accept
1630 a condition at the end of the command, much like the "break"
1631 command does. For instance:
1633 (gdb) catch exception Constraint_Error if Barrier = True
1635 Previously, it was possible to add a condition to such catchpoints,
1636 but it had to be done as a second step, after the catchpoint had been
1637 created, using the "condition" command.
1639 * The "info static-tracepoint-marker" command will now also work on
1640 native Linux targets with in-process agent.
1642 * GDB can now set breakpoints on inlined functions.
1644 * The .gdb_index section has been updated to include symbols for
1645 inlined functions. GDB will ignore older .gdb_index sections by
1646 default, which could cause symbol files to be loaded more slowly
1647 until their .gdb_index sections can be recreated. The new command
1648 "set use-deprecated-index-sections on" will cause GDB to use any older
1649 .gdb_index sections it finds. This will restore performance, but the
1650 ability to set breakpoints on inlined functions will be lost in symbol
1651 files with older .gdb_index sections.
1653 The .gdb_index section has also been updated to record more information
1654 about each symbol. This speeds up the "info variables", "info functions"
1655 and "info types" commands when used with programs having the .gdb_index
1656 section, as well as speeding up debugging with shared libraries using
1657 the .gdb_index section.
1659 * Ada support for GDB/MI Variable Objects has been added.
1661 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1666 ** New command -info-os is the MI equivalent of "info os".
1668 ** Output logs ("set logging" and related) now include MI output.
1672 ** "set use-deprecated-index-sections on|off"
1673 "show use-deprecated-index-sections on|off"
1674 Controls the use of deprecated .gdb_index sections.
1676 ** "catch load" and "catch unload" can be used to stop when a shared
1677 library is loaded or unloaded, respectively.
1679 ** "enable count" can be used to auto-disable a breakpoint after
1682 ** "info vtbl" can be used to show the virtual method tables for
1683 C++ and Java objects.
1685 ** "explore" and its sub commands "explore value" and "explore type"
1686 can be used to recursively explore values and types of
1687 expressions. These commands are available only if GDB is
1688 configured with '--with-python'.
1690 ** "info auto-load" shows status of all kinds of auto-loaded files,
1691 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1692 sequences of commands files, "info auto-load python-scripts"
1693 shows status of auto-loading Python script files,
1694 "info auto-load local-gdbinit" shows status of loading init file
1695 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1696 status of inferior specific thread debugging shared library loading.
1698 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1699 and "show auto-load-scripts" commands have been deprecated, use their
1700 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1701 and "show auto-load python-scripts" counterparts instead.
1703 ** "dprintf location,format,args..." creates a dynamic printf, which
1704 is basically a breakpoint that does a printf and immediately
1705 resumes your program's execution, so it is like a printf that you
1706 can insert dynamically at runtime instead of at compiletime.
1708 ** "set print symbol"
1710 Controls whether GDB attempts to display the symbol, if any,
1711 corresponding to addresses it prints. This defaults to "on", but
1712 you can set it to "off" to restore GDB's previous behavior.
1714 * Deprecated commands
1716 ** For the Renesas Super-H architecture, the "regs" command has been
1717 deprecated, and "info all-registers" should be used instead.
1721 Renesas RL78 rl78-*-elf
1722 HP OpenVMS ia64 ia64-hp-openvms*
1724 * GDBserver supports evaluation of breakpoint conditions. When
1725 support is advertised by GDBserver, GDB may be told to send the
1726 breakpoint conditions in bytecode form to GDBserver. GDBserver
1727 will only report the breakpoint trigger to GDB when its condition
1732 set mips compression
1733 show mips compression
1734 Select the compressed ISA encoding used in functions that have no symbol
1735 information available. The encoding can be set to either of:
1738 and is updated automatically from ELF file flags if available.
1740 set breakpoint condition-evaluation
1741 show breakpoint condition-evaluation
1742 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1743 GDBserver ("target"). Default option "auto" chooses the most efficient
1745 This option can improve debugger efficiency depending on the speed of the
1749 Disable auto-loading globally.
1752 Show auto-loading setting of all kinds of auto-loaded files.
1754 set auto-load gdb-scripts on|off
1755 show auto-load gdb-scripts
1756 Control auto-loading of GDB canned sequences of commands files.
1758 set auto-load python-scripts on|off
1759 show auto-load python-scripts
1760 Control auto-loading of Python script files.
1762 set auto-load local-gdbinit on|off
1763 show auto-load local-gdbinit
1764 Control loading of init file (.gdbinit) from current directory.
1766 set auto-load libthread-db on|off
1767 show auto-load libthread-db
1768 Control auto-loading of inferior specific thread debugging shared library.
1770 set auto-load scripts-directory <dir1>[:<dir2>...]
1771 show auto-load scripts-directory
1772 Set a list of directories from which to load auto-loaded scripts.
1773 Automatically loaded Python scripts and GDB scripts are located in one
1774 of the directories listed by this option.
1775 The delimiter (':' above) may differ according to the host platform.
1777 set auto-load safe-path <dir1>[:<dir2>...]
1778 show auto-load safe-path
1779 Set a list of directories from which it is safe to auto-load files.
1780 The delimiter (':' above) may differ according to the host platform.
1782 set debug auto-load on|off
1783 show debug auto-load
1784 Control display of debugging info for auto-loading the files above.
1786 set dprintf-style gdb|call|agent
1788 Control the way in which a dynamic printf is performed; "gdb"
1789 requests a GDB printf command, while "call" causes dprintf to call a
1790 function in the inferior. "agent" requests that the target agent
1791 (such as GDBserver) do the printing.
1793 set dprintf-function <expr>
1794 show dprintf-function
1795 set dprintf-channel <expr>
1796 show dprintf-channel
1797 Set the function and optional first argument to the call when using
1798 the "call" style of dynamic printf.
1800 set disconnected-dprintf on|off
1801 show disconnected-dprintf
1802 Control whether agent-style dynamic printfs continue to be in effect
1803 after GDB disconnects.
1805 * New configure options
1807 --with-auto-load-dir
1808 Configure default value for the 'set auto-load scripts-directory'
1809 setting above. It defaults to '$debugdir:$datadir/auto-load',
1810 $debugdir representing global debugging info directories (available
1811 via 'show debug-file-directory') and $datadir representing GDB's data
1812 directory (available via 'show data-directory').
1814 --with-auto-load-safe-path
1815 Configure default value for the 'set auto-load safe-path' setting
1816 above. It defaults to the --with-auto-load-dir setting.
1818 --without-auto-load-safe-path
1819 Set 'set auto-load safe-path' to '/', effectively disabling this
1822 * New remote packets
1824 z0/z1 conditional breakpoints extension
1826 The z0/z1 breakpoint insertion packets have been extended to carry
1827 a list of conditional expressions over to the remote stub depending on the
1828 condition evaluation mode. The use of this extension can be controlled
1829 via the "set remote conditional-breakpoints-packet" command.
1833 Specify the signals which the remote stub may pass to the debugged
1834 program without GDB involvement.
1836 * New command line options
1838 --init-command=FILE, -ix Like --command, -x but execute it
1839 before loading inferior.
1840 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1841 execute it before loading inferior.
1843 *** Changes in GDB 7.4
1845 * GDB now handles ambiguous linespecs more consistently; the existing
1846 FILE:LINE support has been expanded to other types of linespecs. A
1847 breakpoint will now be set on all matching locations in all
1848 inferiors, and locations will be added or removed according to
1851 * GDB now allows you to skip uninteresting functions and files when
1852 stepping with the "skip function" and "skip file" commands.
1854 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1855 and "show remote hardware-watchpoint-length-limit". These allows to
1856 set or show the maximum length limit (in bytes) of a remote
1857 target hardware watchpoint.
1859 This allows e.g. to use "unlimited" hardware watchpoints with the
1860 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1861 watchpoints are slower than real hardware watchpoints but are
1862 significantly faster than gdb software watchpoints.
1866 ** The register_pretty_printer function in module gdb.printing now takes
1867 an optional `replace' argument. If True, the new printer replaces any
1870 ** The "maint set python print-stack on|off" command has been
1871 deprecated and will be deleted in GDB 7.5.
1872 A new command: "set python print-stack none|full|message" has
1873 replaced it. Additionally, the default for "print-stack" is
1874 now "message", which just prints the error message without
1877 ** A prompt substitution hook (prompt_hook) is now available to the
1880 ** A new Python module, gdb.prompt has been added to the GDB Python
1881 modules library. This module provides functionality for
1882 escape sequences in prompts (used by set/show
1883 extended-prompt). These escape sequences are replaced by their
1884 corresponding value.
1886 ** Python commands and convenience-functions located in
1887 'data-directory'/python/gdb/command and
1888 'data-directory'/python/gdb/function are now automatically loaded
1891 ** Blocks now provide four new attributes. global_block and
1892 static_block will return the global and static blocks
1893 respectively. is_static and is_global are boolean attributes
1894 that indicate if the block is one of those two types.
1896 ** Symbols now provide the "type" attribute, the type of the symbol.
1898 ** The "gdb.breakpoint" function has been deprecated in favor of
1901 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1902 of a function. This class is based on the "finish" command
1903 available in the CLI.
1905 ** Type objects for struct and union types now allow access to
1906 the fields using standard Python dictionary (mapping) methods.
1907 For example, "some_type['myfield']" now works, as does
1908 "some_type.items()".
1910 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1913 ** A new function, "deep_items" has been added to the gdb.types
1914 module in the GDB Python modules library. This function returns
1915 an iterator over the fields of a struct or union type. Unlike
1916 the standard Python "iteritems" method, it will recursively traverse
1917 any anonymous fields.
1921 ** "*stopped" events can report several new "reason"s, such as
1924 ** Breakpoint changes are now notified using new async records, like
1925 "=breakpoint-modified".
1927 ** New command -ada-task-info.
1929 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1930 $sdir specifies the default system locations of shared libraries.
1931 $pdir specifies the directory where the libpthread used by the application
1934 GDB no longer looks in $sdir and $pdir after it has searched the directories
1935 mentioned in libthread-db-search-path. If you want to search those
1936 directories, they must be specified in libthread-db-search-path.
1937 The default value of libthread-db-search-path on GNU/Linux and Solaris
1938 systems is now "$sdir:$pdir".
1940 $pdir is not supported by gdbserver, it is currently ignored.
1941 $sdir is supported by gdbserver.
1943 * New configure option --with-iconv-bin.
1944 When using the internationalization support like the one in the GNU C
1945 library, GDB will invoke the "iconv" program to get a list of supported
1946 character sets. If this program lives in a non-standard location, one can
1947 use this option to specify where to find it.
1949 * When natively debugging programs on PowerPC BookE processors running
1950 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1951 watchpoints, which specify a mask in addition to an address to watch.
1952 The mask specifies that some bits of an address (the bits which are
1953 reset in the mask) should be ignored when matching the address accessed
1954 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1955 section in the user manual for more details.
1957 * The new option --once causes GDBserver to stop listening for connections once
1958 the first connection is made. The listening port used by GDBserver will
1959 become available after that.
1961 * New commands "info macros" and "alias" have been added.
1963 * New function parameters suffix @entry specifies value of function parameter
1964 at the time the function got called. Entry values are available only since
1970 "!" is now an alias of the "shell" command.
1971 Note that no space is needed between "!" and SHELL COMMAND.
1975 watch EXPRESSION mask MASK_VALUE
1976 The watch command now supports the mask argument which allows creation
1977 of masked watchpoints, if the current architecture supports this feature.
1979 info auto-load-scripts [REGEXP]
1980 This command was formerly named "maintenance print section-scripts".
1981 It is now generally useful and is no longer a maintenance-only command.
1983 info macro [-all] [--] MACRO
1984 The info macro command has new options `-all' and `--'. The first for
1985 printing all definitions of a macro. The second for explicitly specifying
1986 the end of arguments and the beginning of the macro name in case the macro
1987 name starts with a hyphen.
1989 collect[/s] EXPRESSIONS
1990 The tracepoint collect command now takes an optional modifier "/s"
1991 that directs it to dereference pointer-to-character types and
1992 collect the bytes of memory up to a zero byte. The behavior is
1993 similar to what you see when you use the regular print command on a
1994 string. An optional integer following the "/s" sets a bound on the
1995 number of bytes that will be collected.
1998 The trace start command now interprets any supplied arguments as a
1999 note to be recorded with the trace run, with an effect similar to
2000 setting the variable trace-notes.
2003 The trace stop command now interprets any arguments as a note to be
2004 mentioned along with the tstatus report that the trace was stopped
2005 with a command. The effect is similar to setting the variable
2008 * Tracepoints can now be enabled and disabled at any time after a trace
2009 experiment has been started using the standard "enable" and "disable"
2010 commands. It is now possible to start a trace experiment with no enabled
2011 tracepoints; GDB will display a warning, but will allow the experiment to
2012 begin, assuming that tracepoints will be enabled as needed while the trace
2015 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2016 locations with 4-byte instructions, when they were previously
2017 limited to locations with instructions of 5 bytes or longer.
2021 set debug dwarf2-read
2022 show debug dwarf2-read
2023 Turns on or off display of debugging messages related to reading
2024 DWARF debug info. The default is off.
2026 set debug symtab-create
2027 show debug symtab-create
2028 Turns on or off display of debugging messages related to symbol table
2029 creation. The default is off.
2032 show extended-prompt
2033 Set the GDB prompt, and allow escape sequences to be inserted to
2034 display miscellaneous information (see 'help set extended-prompt'
2035 for the list of sequences). This prompt (and any information
2036 accessed through the escape sequences) is updated every time the
2037 prompt is displayed.
2039 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2040 show print entry-values
2041 Set printing of frame argument values at function entry. In some cases
2042 GDB can determine the value of function argument which was passed by the
2043 function caller, even if the value was modified inside the called function.
2045 set debug entry-values
2046 show debug entry-values
2047 Control display of debugging info for determining frame argument values at
2048 function entry and virtual tail call frames.
2050 set basenames-may-differ
2051 show basenames-may-differ
2052 Set whether a source file may have multiple base names.
2053 (A "base name" is the name of a file with the directory part removed.
2054 Example: The base name of "/home/user/hello.c" is "hello.c".)
2055 If set, GDB will canonicalize file names (e.g., expand symlinks)
2056 before comparing them. Canonicalization is an expensive operation,
2057 but it allows the same file be known by more than one base name.
2058 If not set (the default), all source files are assumed to have just
2059 one base name, and gdb will do file name comparisons more efficiently.
2065 Set a user name and notes for the current and any future trace runs.
2066 This is useful for long-running and/or disconnected traces, to
2067 inform others (or yourself) as to who is running the trace, supply
2068 contact information, or otherwise explain what is going on.
2070 set trace-stop-notes
2071 show trace-stop-notes
2072 Set a note attached to the trace run, that is displayed when the
2073 trace has been stopped by a tstop command. This is useful for
2074 instance as an explanation, if you are stopping a trace run that was
2075 started by someone else.
2077 * New remote packets
2081 Dynamically enable a tracepoint in a started trace experiment.
2085 Dynamically disable a tracepoint in a started trace experiment.
2089 Set the user and notes of the trace run.
2093 Query the current status of a tracepoint.
2097 Query the minimum length of instruction at which a fast tracepoint may
2100 * Dcache size (number of lines) and line-size are now runtime-configurable
2101 via "set dcache line" and "set dcache line-size" commands.
2105 Texas Instruments TMS320C6x tic6x-*-*
2109 Renesas RL78 rl78-*-elf
2111 *** Changes in GDB 7.3.1
2113 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2115 *** Changes in GDB 7.3
2117 * GDB has a new command: "thread find [REGEXP]".
2118 It finds the thread id whose name, target id, or thread extra info
2119 matches the given regular expression.
2121 * The "catch syscall" command now works on mips*-linux* targets.
2123 * The -data-disassemble MI command now supports modes 2 and 3 for
2124 dumping the instruction opcodes.
2126 * New command line options
2128 -data-directory DIR Specify DIR as the "data-directory".
2129 This is mostly for testing purposes.
2131 * The "maint set python auto-load on|off" command has been renamed to
2132 "set auto-load-scripts on|off".
2134 * GDB has a new command: "set directories".
2135 It is like the "dir" command except that it replaces the
2136 source path list instead of augmenting it.
2138 * GDB now understands thread names.
2140 On GNU/Linux, "info threads" will display the thread name as set by
2141 prctl or pthread_setname_np.
2143 There is also a new command, "thread name", which can be used to
2144 assign a name internally for GDB to display.
2147 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2148 has been integrated into GDB.
2152 ** The function gdb.Write now accepts an optional keyword 'stream'.
2153 This keyword, when provided, will direct the output to either
2154 stdout, stderr, or GDB's logging output.
2156 ** Parameters can now be be sub-classed in Python, and in particular
2157 you may implement the get_set_doc and get_show_doc functions.
2158 This improves how Parameter set/show documentation is processed
2159 and allows for more dynamic content.
2161 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2162 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2163 have an is_valid method.
2165 ** Breakpoints can now be sub-classed in Python, and in particular
2166 you may implement a 'stop' function that is executed each time
2167 the inferior reaches that breakpoint.
2169 ** New function gdb.lookup_global_symbol looks up a global symbol.
2171 ** GDB values in Python are now callable if the value represents a
2172 function. For example, if 'some_value' represents a function that
2173 takes two integer parameters and returns a value, you can call
2174 that function like so:
2176 result = some_value (10,20)
2178 ** Module gdb.types has been added.
2179 It contains a collection of utilities for working with gdb.Types objects:
2180 get_basic_type, has_field, make_enum_dict.
2182 ** Module gdb.printing has been added.
2183 It contains utilities for writing and registering pretty-printers.
2184 New classes: PrettyPrinter, SubPrettyPrinter,
2185 RegexpCollectionPrettyPrinter.
2186 New function: register_pretty_printer.
2188 ** New commands "info pretty-printers", "enable pretty-printer" and
2189 "disable pretty-printer" have been added.
2191 ** gdb.parameter("directories") is now available.
2193 ** New function gdb.newest_frame returns the newest frame in the
2196 ** The gdb.InferiorThread class has a new "name" attribute. This
2197 holds the thread's name.
2199 ** Python Support for Inferior events.
2200 Python scripts can add observers to be notified of events
2201 occurring in the process being debugged.
2202 The following events are currently supported:
2203 - gdb.events.cont Continue event.
2204 - gdb.events.exited Inferior exited event.
2205 - gdb.events.stop Signal received, and Breakpoint hit events.
2209 ** GDB now puts template parameters in scope when debugging in an
2210 instantiation. For example, if you have:
2212 template<int X> int func (void) { return X; }
2214 then if you step into func<5>, "print X" will show "5". This
2215 feature requires proper debuginfo support from the compiler; it
2216 was added to GCC 4.5.
2218 ** The motion commands "next", "finish", "until", and "advance" now
2219 work better when exceptions are thrown. In particular, GDB will
2220 no longer lose control of the inferior; instead, the GDB will
2221 stop the inferior at the point at which the exception is caught.
2222 This functionality requires a change in the exception handling
2223 code that was introduced in GCC 4.5.
2225 * GDB now follows GCC's rules on accessing volatile objects when
2226 reading or writing target state during expression evaluation.
2227 One notable difference to prior behavior is that "print x = 0"
2228 no longer generates a read of x; the value of the assignment is
2229 now always taken directly from the value being assigned.
2231 * GDB now has some support for using labels in the program's source in
2232 linespecs. For instance, you can use "advance label" to continue
2233 execution to a label.
2235 * GDB now has support for reading and writing a new .gdb_index
2236 section. This section holds a fast index of DWARF debugging
2237 information and can be used to greatly speed up GDB startup and
2238 operation. See the documentation for `save gdb-index' for details.
2240 * The "watch" command now accepts an optional "-location" argument.
2241 When used, this causes GDB to watch the memory referred to by the
2242 expression. Such a watchpoint is never deleted due to it going out
2245 * GDB now supports thread debugging of core dumps on GNU/Linux.
2247 GDB now activates thread debugging using the libthread_db library
2248 when debugging GNU/Linux core dumps, similarly to when debugging
2249 live processes. As a result, when debugging a core dump file, GDB
2250 is now able to display pthread_t ids of threads. For example, "info
2251 threads" shows the same output as when debugging the process when it
2252 was live. In earlier releases, you'd see something like this:
2255 * 1 LWP 6780 main () at main.c:10
2257 While now you see this:
2260 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2262 It is also now possible to inspect TLS variables when debugging core
2265 When debugging a core dump generated on a machine other than the one
2266 used to run GDB, you may need to point GDB at the correct
2267 libthread_db library with the "set libthread-db-search-path"
2268 command. See the user manual for more details on this command.
2270 * When natively debugging programs on PowerPC BookE processors running
2271 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2272 which stop execution of the inferior whenever it executes an instruction
2273 at any address within the specified range. See the "PowerPC Embedded"
2274 section in the user manual for more details.
2276 * New features in the GDB remote stub, GDBserver
2278 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2279 and i686 LynxOS (version 5.x).
2281 ** GDBserver is now supported on Blackfin Linux.
2283 * New native configurations
2285 ia64 HP-UX ia64-*-hpux*
2289 Analog Devices, Inc. Blackfin Processor bfin-*
2291 * Ada task switching is now supported on sparc-elf targets when
2292 debugging a program using the Ravenscar Profile. For more information,
2293 see the "Tasking Support when using the Ravenscar Profile" section
2294 in the GDB user manual.
2296 * Guile support was removed.
2298 * New features in the GNU simulator
2300 ** The --map-info flag lists all known core mappings.
2302 ** CFI flashes may be simulated via the "cfi" device.
2304 *** Changes in GDB 7.2
2306 * Shared library support for remote targets by default
2308 When GDB is configured for a generic, non-OS specific target, like
2309 for example, --target=arm-eabi or one of the many *-*-elf targets,
2310 GDB now queries remote stubs for loaded shared libraries using the
2311 `qXfer:libraries:read' packet. Previously, shared library support
2312 was always disabled for such configurations.
2316 ** Argument Dependent Lookup (ADL)
2318 In C++ ADL lookup directs function search to the namespaces of its
2319 arguments even if the namespace has not been imported.
2329 Here the compiler will search for `foo' in the namespace of 'b'
2330 and find A::foo. GDB now supports this. This construct is commonly
2331 used in the Standard Template Library for operators.
2333 ** Improved User Defined Operator Support
2335 In addition to member operators, GDB now supports lookup of operators
2336 defined in a namespace and imported with a `using' directive, operators
2337 defined in the global scope, operators imported implicitly from an
2338 anonymous namespace, and the ADL operators mentioned in the previous
2340 GDB now also supports proper overload resolution for all the previously
2341 mentioned flavors of operators.
2343 ** static const class members
2345 Printing of static const class members that are initialized in the
2346 class definition has been fixed.
2348 * Windows Thread Information Block access.
2350 On Windows targets, GDB now supports displaying the Windows Thread
2351 Information Block (TIB) structure. This structure is visible either
2352 by using the new command `info w32 thread-information-block' or, by
2353 dereferencing the new convenience variable named `$_tlb', a
2354 thread-specific pointer to the TIB. This feature is also supported
2355 when remote debugging using GDBserver.
2357 * Static tracepoints
2359 Static tracepoints are calls in the user program into a tracing
2360 library. One such library is a port of the LTTng kernel tracer to
2361 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2362 When debugging with GDBserver, GDB now supports combining the GDB
2363 tracepoint machinery with such libraries. For example: the user can
2364 use GDB to probe a static tracepoint marker (a call from the user
2365 program into the tracing library) with the new "strace" command (see
2366 "New commands" below). This creates a "static tracepoint" in the
2367 breakpoint list, that can be manipulated with the same feature set
2368 as fast and regular tracepoints. E.g., collect registers, local and
2369 global variables, collect trace state variables, and define
2370 tracepoint conditions. In addition, the user can collect extra
2371 static tracepoint marker specific data, by collecting the new
2372 $_sdata internal variable. When analyzing the trace buffer, you can
2373 inspect $_sdata like any other variable available to GDB. For more
2374 information, see the "Tracepoints" chapter in GDB user manual. New
2375 remote packets have been defined to support static tracepoints, see
2376 the "New remote packets" section below.
2378 * Better reconstruction of tracepoints after disconnected tracing
2380 GDB will attempt to download the original source form of tracepoint
2381 definitions when starting a trace run, and then will upload these
2382 upon reconnection to the target, resulting in a more accurate
2383 reconstruction of the tracepoints that are in use on the target.
2387 You can now exercise direct control over the ways that GDB can
2388 affect your program. For instance, you can disallow the setting of
2389 breakpoints, so that the program can run continuously (assuming
2390 non-stop mode). In addition, the "observer" variable is available
2391 to switch all of the different controls; in observer mode, GDB
2392 cannot affect the target's behavior at all, which is useful for
2393 tasks like diagnosing live systems in the field.
2395 * The new convenience variable $_thread holds the number of the
2398 * New remote packets
2402 Return the address of the Windows Thread Information Block of a given thread.
2406 In response to several of the tracepoint packets, the target may now
2407 also respond with a number of intermediate `qRelocInsn' request
2408 packets before the final result packet, to have GDB handle
2409 relocating an instruction to execute at a different address. This
2410 is particularly useful for stubs that support fast tracepoints. GDB
2411 reports support for this feature in the qSupported packet.
2415 List static tracepoint markers in the target program.
2419 List static tracepoint markers at a given address in the target
2422 qXfer:statictrace:read
2424 Read the static trace data collected (by a `collect $_sdata'
2425 tracepoint action). The remote stub reports support for this packet
2426 to gdb's qSupported query.
2430 Send the current settings of GDB's permission flags.
2434 Send part of the source (textual) form of a tracepoint definition,
2435 which includes location, conditional, and action list.
2437 * The source command now accepts a -s option to force searching for the
2438 script in the source search path even if the script name specifies
2441 * New features in the GDB remote stub, GDBserver
2443 - GDBserver now support tracepoints (including fast tracepoints, and
2444 static tracepoints). The feature is currently supported by the
2445 i386-linux and amd64-linux builds. See the "Tracepoints support
2446 in gdbserver" section in the manual for more information.
2448 GDBserver JIT compiles the tracepoint's conditional agent
2449 expression bytecode into native code whenever possible for low
2450 overhead dynamic tracepoints conditionals. For such tracepoints,
2451 an expression that examines program state is evaluated when the
2452 tracepoint is reached, in order to determine whether to capture
2453 trace data. If the condition is simple and false, processing the
2454 tracepoint finishes very quickly and no data is gathered.
2456 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2457 for static tracepoints support.
2459 - GDBserver now supports x86_64 Windows 64-bit debugging.
2461 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2462 it understands register description.
2464 * The --batch flag now disables pagination and queries.
2466 * X86 general purpose registers
2468 GDB now supports reading/writing byte, word and double-word x86
2469 general purpose registers directly. This means you can use, say,
2470 $ah or $ax to refer, respectively, to the byte register AH and
2471 16-bit word register AX that are actually portions of the 32-bit
2472 register EAX or 64-bit register RAX.
2474 * The `commands' command now accepts a range of breakpoints to modify.
2475 A plain `commands' following a command that creates multiple
2476 breakpoints affects all the breakpoints set by that command. This
2477 applies to breakpoints set by `rbreak', and also applies when a
2478 single `break' command creates multiple breakpoints (e.g.,
2479 breakpoints on overloaded c++ functions).
2481 * The `rbreak' command now accepts a filename specification as part of
2482 its argument, limiting the functions selected by the regex to those
2483 in the specified file.
2485 * Support for remote debugging Windows and SymbianOS shared libraries
2486 from Unix hosts has been improved. Non Windows GDB builds now can
2487 understand target reported file names that follow MS-DOS based file
2488 system semantics, such as file names that include drive letters and
2489 use the backslash character as directory separator. This makes it
2490 possible to transparently use the "set sysroot" and "set
2491 solib-search-path" on Unix hosts to point as host copies of the
2492 target's shared libraries. See the new command "set
2493 target-file-system-kind" described below, and the "Commands to
2494 specify files" section in the user manual for more information.
2498 eval template, expressions...
2499 Convert the values of one or more expressions under the control
2500 of the string template to a command line, and call it.
2502 set target-file-system-kind unix|dos-based|auto
2503 show target-file-system-kind
2504 Set or show the assumed file system kind for target reported file
2507 save breakpoints <filename>
2508 Save all current breakpoint definitions to a file suitable for use
2509 in a later debugging session. To read the saved breakpoint
2510 definitions, use the `source' command.
2512 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2515 info static-tracepoint-markers
2516 Display information about static tracepoint markers in the target.
2518 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2519 Define a static tracepoint by probing a marker at the given
2520 function, line, address, or marker ID.
2524 Enable and disable observer mode.
2526 set may-write-registers on|off
2527 set may-write-memory on|off
2528 set may-insert-breakpoints on|off
2529 set may-insert-tracepoints on|off
2530 set may-insert-fast-tracepoints on|off
2531 set may-interrupt on|off
2532 Set individual permissions for GDB effects on the target. Note that
2533 some of these settings can have undesirable or surprising
2534 consequences, particularly when changed in the middle of a session.
2535 For instance, disabling the writing of memory can prevent
2536 breakpoints from being inserted, cause single-stepping to fail, or
2537 even crash your program, if you disable after breakpoints have been
2538 inserted. However, GDB should not crash.
2540 set record memory-query on|off
2541 show record memory-query
2542 Control whether to stop the inferior if memory changes caused
2543 by an instruction cannot be recorded.
2548 The disassemble command now supports "start,+length" form of two arguments.
2552 ** GDB now provides a new directory location, called the python directory,
2553 where Python scripts written for GDB can be installed. The location
2554 of that directory is <data-directory>/python, where <data-directory>
2555 is the GDB data directory. For more details, see section `Scripting
2556 GDB using Python' in the manual.
2558 ** The GDB Python API now has access to breakpoints, symbols, symbol
2559 tables, program spaces, inferiors, threads and frame's code blocks.
2560 Additionally, GDB Parameters can now be created from the API, and
2561 manipulated via set/show in the CLI.
2563 ** New functions gdb.target_charset, gdb.target_wide_charset,
2564 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2566 ** New exception gdb.GdbError.
2568 ** Pretty-printers are now also looked up in the current program space.
2570 ** Pretty-printers can now be individually enabled and disabled.
2572 ** GDB now looks for names of Python scripts to auto-load in a
2573 special section named `.debug_gdb_scripts', in addition to looking
2574 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2576 * Tracepoint actions were unified with breakpoint commands. In particular,
2577 there are no longer differences in "info break" output for breakpoints and
2578 tracepoints and the "commands" command can be used for both tracepoints and
2579 regular breakpoints.
2583 ARM Symbian arm*-*-symbianelf*
2585 * D language support.
2586 GDB now supports debugging programs written in the D programming
2589 * GDB now supports the extended ptrace interface for PowerPC which is
2590 available since Linux kernel version 2.6.34. This automatically enables
2591 any hardware breakpoints and additional hardware watchpoints available in
2592 the processor. The old ptrace interface exposes just one hardware
2593 watchpoint and no hardware breakpoints.
2595 * GDB is now able to use the Data Value Compare (DVC) register available on
2596 embedded PowerPC processors to implement in hardware simple watchpoint
2597 conditions of the form:
2599 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2601 This works in native GDB running on Linux kernels with the extended ptrace
2602 interface mentioned above.
2604 *** Changes in GDB 7.1
2608 ** Namespace Support
2610 GDB now supports importing of namespaces in C++. This enables the
2611 user to inspect variables from imported namespaces. Support for
2612 namepace aliasing has also been added. So, if a namespace is
2613 aliased in the current scope (e.g. namepace C=A; ) the user can
2614 print variables using the alias (e.g. (gdb) print C::x).
2618 All known bugs relating to the printing of virtual base class were
2619 fixed. It is now possible to call overloaded static methods using a
2624 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2625 and reinterpret_cast<> are now handled by the C++ expression parser.
2629 Xilinx MicroBlaze microblaze-*-*
2634 Xilinx MicroBlaze microblaze
2637 * Multi-program debugging.
2639 GDB now has support for multi-program (a.k.a. multi-executable or
2640 multi-exec) debugging. This allows for debugging multiple inferiors
2641 simultaneously each running a different program under the same GDB
2642 session. See "Debugging Multiple Inferiors and Programs" in the
2643 manual for more information. This implied some user visible changes
2644 in the multi-inferior support. For example, "info inferiors" now
2645 lists inferiors that are not running yet or that have exited
2646 already. See also "New commands" and "New options" below.
2648 * New tracing features
2650 GDB's tracepoint facility now includes several new features:
2652 ** Trace state variables
2654 GDB tracepoints now include support for trace state variables, which
2655 are variables managed by the target agent during a tracing
2656 experiment. They are useful for tracepoints that trigger each
2657 other, so for instance one tracepoint can count hits in a variable,
2658 and then a second tracepoint has a condition that is true when the
2659 count reaches a particular value. Trace state variables share the
2660 $-syntax of GDB convenience variables, and can appear in both
2661 tracepoint actions and condition expressions. Use the "tvariable"
2662 command to create, and "info tvariables" to view; see "Trace State
2663 Variables" in the manual for more detail.
2667 GDB now includes an option for defining fast tracepoints, which
2668 targets may implement more efficiently, such as by installing a jump
2669 into the target agent rather than a trap instruction. The resulting
2670 speedup can be by two orders of magnitude or more, although the
2671 tradeoff is that some program locations on some target architectures
2672 might not allow fast tracepoint installation, for instance if the
2673 instruction to be replaced is shorter than the jump. To request a
2674 fast tracepoint, use the "ftrace" command, with syntax identical to
2675 the regular trace command.
2677 ** Disconnected tracing
2679 It is now possible to detach GDB from the target while it is running
2680 a trace experiment, then reconnect later to see how the experiment
2681 is going. In addition, a new variable disconnected-tracing lets you
2682 tell the target agent whether to continue running a trace if the
2683 connection is lost unexpectedly.
2687 GDB now has the ability to save the trace buffer into a file, and
2688 then use that file as a target, similarly to you can do with
2689 corefiles. You can select trace frames, print data that was
2690 collected in them, and use tstatus to display the state of the
2691 tracing run at the moment that it was saved. To create a trace
2692 file, use "tsave <filename>", and to use it, do "target tfile
2695 ** Circular trace buffer
2697 You can ask the target agent to handle the trace buffer as a
2698 circular buffer, discarding the oldest trace frames to make room for
2699 newer ones, by setting circular-trace-buffer to on. This feature may
2700 not be available for all target agents.
2705 The disassemble command, when invoked with two arguments, now requires
2706 the arguments to be comma-separated.
2709 The info variables command now displays variable definitions. Files
2710 which only declare a variable are not shown.
2713 The source command is now capable of sourcing Python scripts.
2714 This feature is dependent on the debugger being build with Python
2717 Related to this enhancement is also the introduction of a new command
2718 "set script-extension" (see below).
2720 * New commands (for set/show, see "New options" below)
2722 record save [<FILENAME>]
2723 Save a file (in core file format) containing the process record
2724 execution log for replay debugging at a later time.
2726 record restore <FILENAME>
2727 Restore the process record execution log that was saved at an
2728 earlier time, for replay debugging.
2730 add-inferior [-copies <N>] [-exec <FILENAME>]
2733 clone-inferior [-copies <N>] [ID]
2734 Make a new inferior ready to execute the same program another
2735 inferior has loaded.
2740 maint info program-spaces
2741 List the program spaces loaded into GDB.
2743 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2744 show remote interrupt-sequence
2745 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2746 as the sequence to the remote target in order to interrupt the execution.
2747 Ctrl-C is a default. Some system prefers BREAK which is high level of
2748 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2749 Magic SysRq g. It is BREAK signal and character 'g'.
2751 set remote interrupt-on-connect [on | off]
2752 show remote interrupt-on-connect
2753 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2754 remote target when gdb connects to it. This is needed when you debug
2757 set remotebreak [on | off]
2759 Deprecated. Use "set/show remote interrupt-sequence" instead.
2761 tvariable $NAME [ = EXP ]
2762 Create or modify a trace state variable.
2765 List trace state variables and their values.
2767 delete tvariable $NAME ...
2768 Delete one or more trace state variables.
2771 Evaluate the given expressions without collecting anything into the
2772 trace buffer. (Valid in tracepoint actions only.)
2774 ftrace FN / FILE:LINE / *ADDR
2775 Define a fast tracepoint at the given function, line, or address.
2777 * New expression syntax
2779 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2780 GDB now parses 0b101010 identically with 42.
2784 set follow-exec-mode new|same
2785 show follow-exec-mode
2786 Control whether GDB reuses the same inferior across an exec call or
2787 creates a new one. This is useful to be able to restart the old
2788 executable after the inferior having done an exec call.
2790 set default-collect EXPR, ...
2791 show default-collect
2792 Define a list of expressions to be collected at each tracepoint.
2793 This is a useful way to ensure essential items are not overlooked,
2794 such as registers or a critical global variable.
2796 set disconnected-tracing
2797 show disconnected-tracing
2798 If set to 1, the target is instructed to continue tracing if it
2799 loses its connection to GDB. If 0, the target is to stop tracing
2802 set circular-trace-buffer
2803 show circular-trace-buffer
2804 If set to on, the target is instructed to use a circular trace buffer
2805 and discard the oldest trace frames instead of stopping the trace due
2806 to a full trace buffer. If set to off, the trace stops when the buffer
2807 fills up. Some targets may not support this.
2809 set script-extension off|soft|strict
2810 show script-extension
2811 If set to "off", the debugger does not perform any script language
2812 recognition, and all sourced files are assumed to be GDB scripts.
2813 If set to "soft" (the default), files are sourced according to
2814 filename extension, falling back to GDB scripts if the first
2816 If set to "strict", files are sourced according to filename extension.
2818 set ada trust-PAD-over-XVS on|off
2819 show ada trust-PAD-over-XVS
2820 If off, activate a workaround against a bug in the debugging information
2821 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2822 the GCC sources for more information about the GNAT encoding and
2823 PAD types in particular). It is always safe to set this option to
2824 off, but this introduces a slight performance penalty. The default
2827 * Python API Improvements
2829 ** GDB provides the new class gdb.LazyString. This is useful in
2830 some pretty-printing cases. The new method gdb.Value.lazy_string
2831 provides a simple way to create objects of this type.
2833 ** The fields returned by gdb.Type.fields now have an
2834 `is_base_class' attribute.
2836 ** The new method gdb.Type.range returns the range of an array type.
2838 ** The new method gdb.parse_and_eval can be used to parse and
2839 evaluate an expression.
2841 * New remote packets
2844 Define a trace state variable.
2847 Get the current value of a trace state variable.
2850 Set desired tracing behavior upon disconnection.
2853 Set the trace buffer to be linear or circular.
2856 Get data about the tracepoints currently in use.
2860 Process record now works correctly with hardware watchpoints.
2862 Multiple bug fixes have been made to the mips-irix port, making it
2863 much more reliable. In particular:
2864 - Debugging threaded applications is now possible again. Previously,
2865 GDB would hang while starting the program, or while waiting for
2866 the program to stop at a breakpoint.
2867 - Attaching to a running process no longer hangs.
2868 - An error occurring while loading a core file has been fixed.
2869 - Changing the value of the PC register now works again. This fixes
2870 problems observed when using the "jump" command, or when calling
2871 a function from GDB, or even when assigning a new value to $pc.
2872 - With the "finish" and "return" commands, the return value for functions
2873 returning a small array is now correctly printed.
2874 - It is now possible to break on shared library code which gets executed
2875 during a shared library init phase (code executed while executing
2876 their .init section). Previously, the breakpoint would have no effect.
2877 - GDB is now able to backtrace through the signal handler for
2878 non-threaded programs.
2880 PIE (Position Independent Executable) programs debugging is now supported.
2881 This includes debugging execution of PIC (Position Independent Code) shared
2882 libraries although for that, it should be possible to run such libraries as an
2885 *** Changes in GDB 7.0
2887 * GDB now has an interface for JIT compilation. Applications that
2888 dynamically generate code can create symbol files in memory and register
2889 them with GDB. For users, the feature should work transparently, and
2890 for JIT developers, the interface is documented in the GDB manual in the
2891 "JIT Compilation Interface" chapter.
2893 * Tracepoints may now be conditional. The syntax is as for
2894 breakpoints; either an "if" clause appended to the "trace" command,
2895 or the "condition" command is available. GDB sends the condition to
2896 the target for evaluation using the same bytecode format as is used
2897 for tracepoint actions.
2899 * The disassemble command now supports: an optional /r modifier, print the
2900 raw instructions in hex as well as in symbolic form, and an optional /m
2901 modifier to print mixed source+assembly.
2903 * Process record and replay
2905 In a architecture environment that supports ``process record and
2906 replay'', ``process record and replay'' target can record a log of
2907 the process execution, and replay it with both forward and reverse
2910 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2911 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2912 set execution-direction {forward|reverse}, for targets that support
2915 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2916 feature is available with a native GDB running on kernel version
2919 * GDB now has support for multi-byte and wide character sets on the
2920 target. Strings whose character type is wchar_t, char16_t, or
2921 char32_t are now correctly printed. GDB supports wide- and unicode-
2922 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2923 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2924 `printf'. This feature requires iconv to work properly; if your
2925 system does not have a working iconv, GDB can use GNU libiconv. See
2926 the installation instructions for more information.
2928 * GDB now supports automatic retrieval of shared library files from
2929 remote targets. To use this feature, specify a system root that begins
2930 with the `remote:' prefix, either via the `set sysroot' command or via
2931 the `--with-sysroot' configure-time option.
2933 * "info sharedlibrary" now takes an optional regex of libraries to show,
2934 and it now reports if a shared library has no debugging information.
2936 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2937 now complete on file names.
2939 * When completing in expressions, gdb will attempt to limit
2940 completions to allowable structure or union fields, where appropriate.
2941 For instance, consider:
2943 # struct example { int f1; double f2; };
2944 # struct example variable;
2947 If the user types TAB at the end of this command line, the available
2948 completions will be "f1" and "f2".
2950 * Inlined functions are now supported. They show up in backtraces, and
2951 the "step", "next", and "finish" commands handle them automatically.
2953 * GDB now supports the token-splicing (##) and stringification (#)
2954 operators when expanding macros. It also supports variable-arity
2957 * GDB now supports inspecting extra signal information, exported by
2958 the new $_siginfo convenience variable. The feature is currently
2959 implemented on linux ARM, i386 and amd64.
2961 * GDB can now display the VFP floating point registers and NEON vector
2962 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2963 can provide these registers (requires Linux 2.6.30 or later). Remote
2964 and simulator targets may also provide them.
2966 * New remote packets
2969 Search memory for a sequence of bytes.
2972 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2973 operation over reliable transport links. Use of this packet is
2974 controlled by the `set remote noack-packet' command.
2977 Kill the process with the specified process ID. Use this in preference
2978 to `k' when multiprocess protocol extensions are supported.
2981 Obtains additional operating system information
2985 Read or write additional signal information.
2987 * Removed remote protocol undocumented extension
2989 An undocumented extension to the remote protocol's `S' stop reply
2990 packet that permited the stub to pass a process id was removed.
2991 Remote servers should use the `T' stop reply packet instead.
2993 * GDB now supports multiple function calling conventions according to the
2994 DWARF-2 DW_AT_calling_convention function attribute.
2996 * The SH target utilizes the aforementioned change to distinguish between gcc
2997 and Renesas calling convention. It also adds the new CLI commands
2998 `set/show sh calling-convention'.
3000 * GDB can now read compressed debug sections, as produced by GNU gold
3001 with the --compress-debug-sections=zlib flag.
3003 * 64-bit core files are now supported on AIX.
3005 * Thread switching is now supported on Tru64.
3007 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3008 which will be allocated using malloc later in program execution.
3010 * The qXfer:libraries:read remote procotol packet now allows passing a
3011 list of section offsets.
3013 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3014 conditions handling signals delivered during attach or thread creation
3015 have also been fixed.
3017 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3018 From the user's standpoint, all unqualified instances of True and False
3019 are treated as the standard definitions, regardless of context.
3021 * GDB now parses C++ symbol and type names more flexibly. For
3024 template<typename T> class C { };
3027 GDB will now correctly handle all of:
3029 ptype C<char const *>
3030 ptype C<char const*>
3031 ptype C<const char *>
3032 ptype C<const char*>
3034 * New features in the GDB remote stub, gdbserver
3036 - The "--wrapper" command-line argument tells gdbserver to use a
3037 wrapper program to launch programs for debugging.
3039 - On PowerPC and S/390 targets, it is now possible to use a single
3040 gdbserver executable to debug both 32-bit and 64-bit programs.
3041 (This requires gdbserver itself to be built as a 64-bit executable.)
3043 - gdbserver uses the new noack protocol mode for TCP connections to
3044 reduce communications latency, if also supported and enabled in GDB.
3046 - Support for the sparc64-linux-gnu target is now included in
3049 - The amd64-linux build of gdbserver now supports debugging both
3050 32-bit and 64-bit programs.
3052 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3053 now support hardware watchpoints, and will use them automatically
3058 GDB now has support for scripting using Python. Whether this is
3059 available is determined at configure time.
3061 New GDB commands can now be written in Python.
3063 * Ada tasking support
3065 Ada tasks can now be inspected in GDB. The following commands have
3069 Print the list of Ada tasks.
3071 Print detailed information about task number N.
3073 Print the task number of the current task.
3075 Switch the context of debugging to task number N.
3077 * Support for user-defined prefixed commands. The "define" command can
3078 add new commands to existing prefixes, e.g. "target".
3080 * Multi-inferior, multi-process debugging.
3082 GDB now has generalized support for multi-inferior debugging. See
3083 "Debugging Multiple Inferiors" in the manual for more information.
3084 Although availability still depends on target support, the command
3085 set is more uniform now. The GNU/Linux specific multi-forks support
3086 has been migrated to this new framework. This implied some user
3087 visible changes; see "New commands" and also "Removed commands"
3090 * Target descriptions can now describe the target OS ABI. See the
3091 "Target Description Format" section in the user manual for more
3094 * Target descriptions can now describe "compatible" architectures
3095 to indicate that the target can execute applications for a different
3096 architecture in addition to those for the main target architecture.
3097 See the "Target Description Format" section in the user manual for
3100 * Multi-architecture debugging.
3102 GDB now includes general supports for debugging applications on
3103 hybrid systems that use more than one single processor architecture
3104 at the same time. Each such hybrid architecture still requires
3105 specific support to be added. The only hybrid architecture supported
3106 in this version of GDB is the Cell Broadband Engine.
3108 * GDB now supports integrated debugging of Cell/B.E. applications that
3109 use both the PPU and SPU architectures. To enable support for hybrid
3110 Cell/B.E. debugging, you need to configure GDB to support both the
3111 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3112 --enable-targets configure option.
3114 * Non-stop mode debugging.
3116 For some targets, GDB now supports an optional mode of operation in
3117 which you can examine stopped threads while other threads continue
3118 to execute freely. This is referred to as non-stop mode, with the
3119 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3120 section in the user manual for more information.
3122 To be able to support remote non-stop debugging, a remote stub needs
3123 to implement the non-stop mode remote protocol extensions, as
3124 described in the "Remote Non-Stop" section of the user manual. The
3125 GDB remote stub, gdbserver, has been adjusted to support these
3126 extensions on linux targets.
3128 * New commands (for set/show, see "New options" below)
3130 catch syscall [NAME(S) | NUMBER(S)]
3131 Catch system calls. Arguments, which should be names of system
3132 calls or their numbers, mean catch only those syscalls. Without
3133 arguments, every syscall will be caught. When the inferior issues
3134 any of the specified syscalls, GDB will stop and announce the system
3135 call, both when it is called and when its call returns. This
3136 feature is currently available with a native GDB running on the
3137 Linux Kernel, under the following architectures: x86, x86_64,
3138 PowerPC and PowerPC64.
3140 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3142 Search memory for a sequence of bytes.
3144 maint set python print-stack
3145 maint show python print-stack
3146 Show a stack trace when an error is encountered in a Python script.
3149 Invoke CODE by passing it to the Python interpreter.
3154 These allow macros to be defined, undefined, and listed
3158 Show operating system information about processes.
3161 List the inferiors currently under GDB's control.
3164 Switch focus to inferior number NUM.
3167 Detach from inferior number NUM.
3170 Kill inferior number NUM.
3174 set spu stop-on-load
3175 show spu stop-on-load
3176 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3178 set spu auto-flush-cache
3179 show spu auto-flush-cache
3180 Control whether to automatically flush the software-managed cache
3181 during Cell/B.E. debugging.
3183 set sh calling-convention
3184 show sh calling-convention
3185 Control the calling convention used when calling SH target functions.
3188 show debug timestamp
3189 Control display of timestamps with GDB debugging output.
3191 set disassemble-next-line
3192 show disassemble-next-line
3193 Control display of disassembled source lines or instructions when
3196 set remote noack-packet
3197 show remote noack-packet
3198 Set/show the use of remote protocol QStartNoAckMode packet. See above
3199 under "New remote packets."
3201 set remote query-attached-packet
3202 show remote query-attached-packet
3203 Control use of remote protocol `qAttached' (query-attached) packet.
3205 set remote read-siginfo-object
3206 show remote read-siginfo-object
3207 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3210 set remote write-siginfo-object
3211 show remote write-siginfo-object
3212 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3215 set remote reverse-continue
3216 show remote reverse-continue
3217 Control use of remote protocol 'bc' (reverse-continue) packet.
3219 set remote reverse-step
3220 show remote reverse-step
3221 Control use of remote protocol 'bs' (reverse-step) packet.
3223 set displaced-stepping
3224 show displaced-stepping
3225 Control displaced stepping mode. Displaced stepping is a way to
3226 single-step over breakpoints without removing them from the debuggee.
3227 Also known as "out-of-line single-stepping".
3230 show debug displaced
3231 Control display of debugging info for displaced stepping.
3233 maint set internal-error
3234 maint show internal-error
3235 Control what GDB does when an internal error is detected.
3237 maint set internal-warning
3238 maint show internal-warning
3239 Control what GDB does when an internal warning is detected.
3244 Use a wrapper program to launch programs for debugging.
3246 set multiple-symbols (all|ask|cancel)
3247 show multiple-symbols
3248 The value of this variable can be changed to adjust the debugger behavior
3249 when an expression or a breakpoint location contains an ambiguous symbol
3250 name (an overloaded function name, for instance).
3252 set breakpoint always-inserted
3253 show breakpoint always-inserted
3254 Keep breakpoints always inserted in the target, as opposed to inserting
3255 them when resuming the target, and removing them when the target stops.
3256 This option can improve debugger performance on slow remote targets.
3258 set arm fallback-mode (arm|thumb|auto)
3259 show arm fallback-mode
3260 set arm force-mode (arm|thumb|auto)
3262 These commands control how ARM GDB determines whether instructions
3263 are ARM or Thumb. The default for both settings is auto, which uses
3264 the current CPSR value for instructions without symbols; previous
3265 versions of GDB behaved as if "set arm fallback-mode arm".
3267 set disable-randomization
3268 show disable-randomization
3269 Standalone programs run with the virtual address space randomization enabled
3270 by default on some platforms. This option keeps the addresses stable across
3271 multiple debugging sessions.
3275 Control whether other threads are stopped or not when some thread hits
3280 Requests that asynchronous execution is enabled in the target, if available.
3281 In this case, it's possible to resume target in the background, and interact
3282 with GDB while the target is running. "show target-async" displays the
3283 current state of asynchronous execution of the target.
3285 set target-wide-charset
3286 show target-wide-charset
3287 The target-wide-charset is the name of the character set that GDB
3288 uses when printing characters whose type is wchar_t.
3290 set tcp auto-retry (on|off)
3292 set tcp connect-timeout
3293 show tcp connect-timeout
3294 These commands allow GDB to retry failed TCP connections to a remote stub
3295 with a specified timeout period; this is useful if the stub is launched
3296 in parallel with GDB but may not be ready to accept connections immediately.
3298 set libthread-db-search-path
3299 show libthread-db-search-path
3300 Control list of directories which GDB will search for appropriate
3303 set schedule-multiple (on|off)
3304 show schedule-multiple
3305 Allow GDB to resume all threads of all processes or only threads of
3306 the current process.
3310 Use more aggressive caching for accesses to the stack. This improves
3311 performance of remote debugging (particularly backtraces) without
3312 affecting correctness.
3314 set interactive-mode (on|off|auto)
3315 show interactive-mode
3316 Control whether GDB runs in interactive mode (on) or not (off).
3317 When in interactive mode, GDB waits for the user to answer all
3318 queries. Otherwise, GDB does not wait and assumes the default
3319 answer. When set to auto (the default), GDB determines which
3320 mode to use based on the stdin settings.
3325 For program forks, this is replaced by the new more generic `info
3326 inferiors' command. To list checkpoints, you can still use the
3327 `info checkpoints' command, which was an alias for the `info forks'
3331 Replaced by the new `inferior' command. To switch between
3332 checkpoints, you can still use the `restart' command, which was an
3333 alias for the `fork' command.
3336 This is removed, since some targets don't have a notion of
3337 processes. To switch between processes, you can still use the
3338 `inferior' command using GDB's own inferior number.
3341 For program forks, this is replaced by the new more generic `kill
3342 inferior' command. To delete a checkpoint, you can still use the
3343 `delete checkpoint' command, which was an alias for the `delete
3347 For program forks, this is replaced by the new more generic `detach
3348 inferior' command. To detach a checkpoint, you can still use the
3349 `detach checkpoint' command, which was an alias for the `detach
3352 * New native configurations
3354 x86/x86_64 Darwin i[34567]86-*-darwin*
3356 x86_64 MinGW x86_64-*-mingw*
3360 Lattice Mico32 lm32-*
3361 x86 DICOS i[34567]86-*-dicos*
3362 x86_64 DICOS x86_64-*-dicos*
3365 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3366 (mingw32ce) debugging.
3372 These commands were actually not implemented on any target.
3374 *** Changes in GDB 6.8
3376 * New native configurations
3378 NetBSD/hppa hppa*-*netbsd*
3379 Xtensa GNU/Linux xtensa*-*-linux*
3383 NetBSD/hppa hppa*-*-netbsd*
3384 Xtensa GNU/Lunux xtensa*-*-linux*
3386 * Change in command line behavior -- corefiles vs. process ids.
3388 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3389 attaching to process NUMBER fails, GDB no longer attempts to open a
3390 core file named NUMBER. Attaching to a program using the -c option
3391 is no longer supported. Instead, use the '-p' or '--pid' options.
3393 * GDB can now be built as a native debugger for debugging Windows x86
3394 (mingw32) Portable Executable (PE) programs.
3396 * Pending breakpoints no longer change their number when their address
3399 * GDB now supports breakpoints with multiple locations,
3400 including breakpoints on C++ constructors, inside C++ templates,
3401 and in inlined functions.
3403 * GDB's ability to debug optimized code has been improved. GDB more
3404 accurately identifies function bodies and lexical blocks that occupy
3405 more than one contiguous range of addresses.
3407 * Target descriptions can now describe registers for PowerPC.
3409 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3410 registers on PowerPC targets.
3412 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3413 targets even when the libthread_db library is not available.
3415 * The GDB remote stub, gdbserver, now supports the new file transfer
3416 commands (remote put, remote get, and remote delete).
3418 * The GDB remote stub, gdbserver, now supports run and attach in
3419 extended-remote mode.
3421 * hppa*64*-*-hpux11* target broken
3422 The debugger is unable to start a program and fails with the following
3423 error: "Error trying to get information about dynamic linker".
3424 The gdb-6.7 release is also affected.
3426 * GDB now supports the --enable-targets= configure option to allow
3427 building a single GDB executable that supports multiple remote
3428 target architectures.
3430 * GDB now supports debugging C and C++ programs which use the
3431 Decimal Floating Point extension. In addition, the PowerPC target
3432 now has a set of pseudo-registers to inspect decimal float values
3433 stored in two consecutive float registers.
3435 * The -break-insert MI command can optionally create pending
3438 * Improved support for debugging Ada
3439 Many improvements to the Ada language support have been made. These
3441 - Better support for Ada2005 interface types
3442 - Improved handling of arrays and slices in general
3443 - Better support for Taft-amendment types
3444 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3446 - Improved command completion in Ada
3449 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3454 set print frame-arguments (all|scalars|none)
3455 show print frame-arguments
3456 The value of this variable can be changed to control which argument
3457 values should be printed by the debugger when displaying a frame.
3462 Transfer files to and from a remote target, and delete remote files.
3469 Transfer files to and from a remote target, and delete remote files.
3471 * New remote packets
3478 Open, close, read, write, and delete files on the remote system.
3481 Attach to an existing process on the remote system, in extended-remote
3485 Run a new process on the remote system, in extended-remote mode.
3487 *** Changes in GDB 6.7
3489 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3490 bfd, libiberty and opcodes, as revealed by static analysis donated by
3491 Coverity, Inc. (http://scan.coverity.com).
3493 * When looking up multiply-defined global symbols, GDB will now prefer the
3494 symbol definition in the current shared library if it was built using the
3495 -Bsymbolic linker option.
3497 * When the Text User Interface (TUI) is not configured, GDB will now
3498 recognize the -tui command-line option and print a message that the TUI
3501 * The GDB remote stub, gdbserver, now has lower overhead for high
3502 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3504 * GDB for MIPS targets now autodetects whether a remote target provides
3505 32-bit or 64-bit register values.
3507 * Support for C++ member pointers has been improved.
3509 * GDB now understands XML target descriptions, which specify the
3510 target's overall architecture. GDB can read a description from
3511 a local file or over the remote serial protocol.
3513 * Vectors of single-byte data use a new integer type which is not
3514 automatically displayed as character or string data.
3516 * The /s format now works with the print command. It displays
3517 arrays of single-byte integers and pointers to single-byte integers
3520 * Target descriptions can now describe target-specific registers,
3521 for architectures which have implemented the support (currently
3522 only ARM, M68K, and MIPS).
3524 * GDB and the GDB remote stub, gdbserver, now support the XScale
3527 * The GDB remote stub, gdbserver, has been updated to support
3528 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3529 has been rewritten to use the standard GDB remote protocol.
3531 * GDB can now step into C++ functions which are called through thunks.
3533 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3535 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3536 layout. It also supports a TextSeg= and DataSeg= response when only
3537 segment base addresses (rather than offsets) are available.
3539 * The /i format now outputs any trailing branch delay slot instructions
3540 immediately following the last instruction within the count specified.
3542 * The GDB remote protocol "T" stop reply packet now supports a
3543 "library" response. Combined with the new "qXfer:libraries:read"
3544 packet, this response allows GDB to debug shared libraries on targets
3545 where the operating system manages the list of loaded libraries (e.g.
3546 Windows and SymbianOS).
3548 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3549 (DLLs) on Windows and Windows CE targets.
3551 * GDB now supports a faster verification that a .debug file matches its binary
3552 according to its build-id signature, if the signature is present.
3558 Enable or disable hardware flow control (RTS/CTS) on the serial port
3559 when debugging using remote targets.
3561 set mem inaccessible-by-default
3562 show mem inaccessible-by-default
3563 If the target supplies a memory map, for instance via the remote
3564 protocol's "qXfer:memory-map:read" packet, setting this variable
3565 prevents GDB from accessing memory outside the memory map. This
3566 is useful for targets with memory mapped registers or which react
3567 badly to accesses of unmapped address space.
3569 set breakpoint auto-hw
3570 show breakpoint auto-hw
3571 If the target supplies a memory map, for instance via the remote
3572 protocol's "qXfer:memory-map:read" packet, setting this variable
3573 lets GDB use hardware breakpoints automatically for memory regions
3574 where it can not use software breakpoints. This covers both the
3575 "break" command and internal breakpoints used for other commands
3576 including "next" and "finish".
3579 catch exception unhandled
3580 Stop the program execution when Ada exceptions are raised.
3583 Stop the program execution when an Ada assertion failed.
3587 Set an alternate system root for target files. This is a more
3588 general version of "set solib-absolute-prefix", which is now
3589 an alias to "set sysroot".
3592 Provide extended SPU facility status information. This set of
3593 commands is available only when debugging the Cell/B.E. SPU
3596 * New native configurations
3598 OpenBSD/sh sh*-*openbsd*
3601 unset tdesc filename
3603 Use the specified local file as an XML target description, and do
3604 not query the target for its built-in description.
3608 OpenBSD/sh sh*-*-openbsd*
3609 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3610 Toshiba Media Processor mep-elf
3612 * New remote packets
3615 Ignore the specified signals; pass them directly to the debugged program
3616 without stopping other threads or reporting them to GDB.
3618 qXfer:features:read:
3619 Read an XML target description from the target, which describes its
3624 Read or write contents of an spufs file on the target system. These
3625 packets are available only on the Cell/B.E. SPU architecture.
3627 qXfer:libraries:read:
3628 Report the loaded shared libraries. Combined with new "T" packet
3629 response, this packet allows GDB to debug shared libraries on
3630 targets where the operating system manages the list of loaded
3631 libraries (e.g. Windows and SymbianOS).
3635 Support for these obsolete configurations has been removed.
3643 i[34567]86-*-lynxos*
3644 i[34567]86-*-netware*
3645 i[34567]86-*-sco3.2v5*
3646 i[34567]86-*-sco3.2v4*
3648 i[34567]86-*-sysv4.2*
3651 i[34567]86-*-unixware2*
3652 i[34567]86-*-unixware*
3661 * Other removed features
3668 Various m68k-only ROM monitors.
3675 Various Renesas ROM monitors and debugging interfaces for SH and
3680 Support for a Macraigor serial interface to on-chip debugging.
3681 GDB does not directly support the newer parallel or USB
3686 A debug information format. The predecessor to DWARF 2 and
3687 DWARF 3, which are still supported.
3689 Support for the HP aCC compiler on HP-UX/PA-RISC
3691 SOM-encapsulated symbolic debugging information, automatic
3692 invocation of pxdb, and the aCC custom C++ ABI. This does not
3693 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3694 with aCC can still be debugged on an assembly level.
3696 MIPS ".pdr" sections
3698 A MIPS-specific format used to describe stack frame layout
3699 in debugging information.
3703 GDB could work with an older version of Guile to debug
3704 the interpreter and Scheme programs running in it.
3706 set mips stack-arg-size
3707 set mips saved-gpreg-size
3709 Use "set mips abi" to control parameter passing for MIPS.
3711 *** Changes in GDB 6.6
3716 Cell Broadband Engine SPU spu-elf
3718 * GDB can now be configured as a cross-debugger targeting native Windows
3719 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3720 running on a Windows system over TCP/IP to debug Windows programs.
3722 * The GDB remote stub, gdbserver, has been updated to support Windows and
3723 Cygwin debugging. Both single-threaded and multi-threaded programs are
3726 * The "set trust-readonly-sections" command works again. This command was
3727 broken in GDB 6.3, 6.4, and 6.5.
3729 * The "load" command now supports writing to flash memory, if the remote
3730 stub provides the required support.
3732 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3733 longer requires symbolic debug information (e.g. DWARF-2).
3738 unset substitute-path
3739 show substitute-path
3740 Manage a list of substitution rules that GDB uses to rewrite the name
3741 of the directories where the sources are located. This can be useful
3742 for instance when the sources were moved to a different location
3743 between compilation and debugging.
3747 Print each CLI command as it is executed. Each command is prefixed with
3748 a number of `+' symbols representing the nesting depth.
3749 The source command now has a `-v' option to enable the same feature.
3753 The ARM Demon monitor support (RDP protocol, "target rdp").
3755 Kernel Object Display, an embedded debugging feature which only worked with
3756 an obsolete version of Cisco IOS.
3758 The 'set download-write-size' and 'show download-write-size' commands.
3760 * New remote packets
3763 Tell a stub about GDB client features, and request remote target features.
3764 The first feature implemented is PacketSize, which allows the target to
3765 specify the size of packets it can handle - to minimize the number of
3766 packets required and improve performance when connected to a remote
3770 Fetch an OS auxilliary vector from the remote stub. This packet is a
3771 more efficient replacement for qPart:auxv:read.
3773 qXfer:memory-map:read:
3774 Fetch a memory map from the remote stub, including information about
3775 RAM, ROM, and flash memory devices.
3780 Erase and program a flash memory device.
3782 * Removed remote packets
3785 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3786 used it, and only gdbserver implemented it.
3788 *** Changes in GDB 6.5
3792 Renesas M32C/M16C m32c-elf
3794 Morpho Technologies ms1 ms1-elf
3798 init-if-undefined Initialize a convenience variable, but
3799 only if it doesn't already have a value.
3801 The following commands are presently only implemented for native GNU/Linux:
3803 checkpoint Save a snapshot of the program state.
3805 restart <n> Return the program state to a
3806 previously saved state.
3808 info checkpoints List currently saved checkpoints.
3810 delete-checkpoint <n> Delete a previously saved checkpoint.
3812 set|show detach-on-fork Tell gdb whether to detach from a newly
3813 forked process, or to keep debugging it.
3815 info forks List forks of the user program that
3816 are available to be debugged.
3818 fork <n> Switch to debugging one of several
3819 forks of the user program that are
3820 available to be debugged.
3822 delete-fork <n> Delete a fork from the list of forks
3823 that are available to be debugged (and
3824 kill the forked process).
3826 detach-fork <n> Delete a fork from the list of forks
3827 that are available to be debugged (and
3828 allow the process to continue).
3832 Morpho Technologies ms2 ms1-elf
3834 * Improved Windows host support
3836 GDB now builds as a cross debugger hosted on i686-mingw32, including
3837 native console support, and remote communications using either
3838 network sockets or serial ports.
3840 * Improved Modula-2 language support
3842 GDB can now print most types in the Modula-2 syntax. This includes:
3843 basic types, set types, record types, enumerated types, range types,
3844 pointer types and ARRAY types. Procedure var parameters are correctly
3845 printed and hexadecimal addresses and character constants are also
3846 written in the Modula-2 syntax. Best results can be obtained by using
3847 GNU Modula-2 together with the -gdwarf-2 command line option.
3851 The ARM rdi-share module.
3853 The Netware NLM debug server.
3855 *** Changes in GDB 6.4
3857 * New native configurations
3859 OpenBSD/arm arm*-*-openbsd*
3860 OpenBSD/mips64 mips64-*-openbsd*
3864 Morpho Technologies ms1 ms1-elf
3866 * New command line options
3868 --batch-silent As for --batch, but totally silent.
3869 --return-child-result The debugger will exist with the same value
3870 the child (debugged) program exited with.
3871 --eval-command COMMAND, -ex COMMAND
3872 Execute a single GDB CLI command. This may be
3873 specified multiple times and in conjunction
3874 with the --command (-x) option.
3876 * Deprecated commands removed
3878 The following commands, that were deprecated in 2000, have been
3882 set|show arm disassembly-flavor set|show arm disassembler
3883 othernames set arm disassembler
3884 set|show remotedebug set|show debug remote
3885 set|show archdebug set|show debug arch
3886 set|show eventdebug set|show debug event
3889 * New BSD user-level threads support
3891 It is now possible to debug programs using the user-level threads
3892 library on OpenBSD and FreeBSD. Currently supported (target)
3895 FreeBSD/amd64 x86_64-*-freebsd*
3896 FreeBSD/i386 i386-*-freebsd*
3897 OpenBSD/i386 i386-*-openbsd*
3899 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3900 are not yet supported.
3902 * New support for Matsushita MN10300 w/sim added
3903 (Work in progress). mn10300-elf.
3905 * REMOVED configurations and files
3907 VxWorks and the XDR protocol *-*-vxworks
3908 Motorola MCORE mcore-*-*
3909 National Semiconductor NS32000 ns32k-*-*
3911 * New "set print array-indexes" command
3913 After turning this setting "on", GDB prints the index of each element
3914 when displaying arrays. The default is "off" to preserve the previous
3917 * VAX floating point support
3919 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3921 * User-defined command support
3923 In addition to using $arg0..$arg9 for argument passing, it is now possible
3924 to use $argc to determine now many arguments have been passed. See the
3925 section on user-defined commands in the user manual for more information.
3927 *** Changes in GDB 6.3:
3929 * New command line option
3931 GDB now accepts -l followed by a number to set the timeout for remote
3934 * GDB works with GCC -feliminate-dwarf2-dups
3936 GDB now supports a more compact representation of DWARF-2 debug
3937 information using DW_FORM_ref_addr references. These are produced
3938 by GCC with the option -feliminate-dwarf2-dups and also by some
3939 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3940 to use -feliminate-dwarf2-dups.
3942 * Internationalization
3944 When supported by the host system, GDB will be built with
3945 internationalization (libintl). The task of marking up the sources is
3946 continued, we're looking forward to our first translation.
3950 Initial support for debugging programs compiled with the GNAT
3951 implementation of the Ada programming language has been integrated
3952 into GDB. In this release, support is limited to expression evaluation.
3954 * New native configurations
3956 GNU/Linux/m32r m32r-*-linux-gnu
3960 GDB's remote protocol now includes support for the 'p' packet. This
3961 packet is used to fetch individual registers from a remote inferior.
3963 * END-OF-LIFE registers[] compatibility module
3965 GDB's internal register infrastructure has been completely rewritten.
3966 The new infrastructure making possible the implementation of key new
3967 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3970 GDB 6.3 will be the last release to include the the registers[]
3971 compatibility module that allowed out-of-date configurations to
3972 continue to work. This change directly impacts the following
3982 powerpc bdm protocol
3984 Unless there is activity to revive these configurations, they will be
3985 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3987 * OBSOLETE configurations and files
3989 Configurations that have been declared obsolete in this release have
3990 been commented out. Unless there is activity to revive these
3991 configurations, the next release of GDB will have their sources
3992 permanently REMOVED.
4001 *** Changes in GDB 6.2.1:
4003 * MIPS `break main; run' gave an heuristic-fence-post warning
4005 When attempting to run even a simple program, a warning about
4006 heuristic-fence-post being hit would be reported. This problem has
4009 * MIPS IRIX 'long double' crashed GDB
4011 When examining a long double variable, GDB would get a segmentation
4012 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4013 IRIX long double values).
4017 A bug in the VAX stack code was causing problems with the "next"
4018 command. This problem has been fixed.
4020 *** Changes in GDB 6.2:
4022 * Fix for ``many threads''
4024 On GNU/Linux systems that use the NPTL threads library, a program
4025 rapidly creating and deleting threads would confuse GDB leading to the
4028 ptrace: No such process.
4029 thread_db_get_info: cannot get thread info: generic error
4031 This problem has been fixed.
4033 * "-async" and "-noasync" options removed.
4035 Support for the broken "-noasync" option has been removed (it caused
4038 * New ``start'' command.
4040 This command runs the program until the begining of the main procedure.
4042 * New BSD Kernel Data Access Library (libkvm) interface
4044 Using ``target kvm'' it is now possible to debug kernel core dumps and
4045 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4046 platforms. Currently supported (native-only) configurations are:
4048 FreeBSD/amd64 x86_64-*-freebsd*
4049 FreeBSD/i386 i?86-*-freebsd*
4050 NetBSD/i386 i?86-*-netbsd*
4051 NetBSD/m68k m68*-*-netbsd*
4052 NetBSD/sparc sparc-*-netbsd*
4053 OpenBSD/amd64 x86_64-*-openbsd*
4054 OpenBSD/i386 i?86-*-openbsd*
4055 OpenBSD/m68k m68*-openbsd*
4056 OpenBSD/sparc sparc-*-openbsd*
4058 * Signal trampoline code overhauled
4060 Many generic problems with GDB's signal handling code have been fixed.
4061 These include: backtraces through non-contiguous stacks; recognition
4062 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4063 call; backtrace through a signal trampoline; step into and out of
4064 signal handlers; and single-stepping in the signal trampoline.
4066 Please note that kernel bugs are a limiting factor here. These
4067 features have been shown to work on an s390 GNU/Linux system that
4068 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4070 * Cygwin support for DWARF 2 added.
4072 * New native configurations
4074 GNU/Linux/hppa hppa*-*-linux*
4075 OpenBSD/hppa hppa*-*-openbsd*
4076 OpenBSD/m68k m68*-*-openbsd*
4077 OpenBSD/m88k m88*-*-openbsd*
4078 OpenBSD/powerpc powerpc-*-openbsd*
4079 NetBSD/vax vax-*-netbsd*
4080 OpenBSD/vax vax-*-openbsd*
4082 * END-OF-LIFE frame compatibility module
4084 GDB's internal frame infrastructure has been completely rewritten.
4085 The new infrastructure making it possible to support key new features
4086 including DWARF 2 Call Frame Information. To aid in the task of
4087 migrating old configurations to this new infrastructure, a
4088 compatibility module, that allowed old configurations to continue to
4089 work, was also included.
4091 GDB 6.2 will be the last release to include this frame compatibility
4092 module. This change directly impacts the following configurations:
4102 Unless there is activity to revive these configurations, they will be
4103 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4105 * REMOVED configurations and files
4107 Sun 3, running SunOS 3 m68*-*-sunos3*
4108 Sun 3, running SunOS 4 m68*-*-sunos4*
4109 Sun 2, running SunOS 3 m68000-*-sunos3*
4110 Sun 2, running SunOS 4 m68000-*-sunos4*
4111 Motorola 680x0 running LynxOS m68*-*-lynxos*
4112 AT&T 3b1/Unix pc m68*-att-*
4113 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4114 decstation mips-dec-* mips-little-*
4115 riscos mips-*-riscos* mips-*-sysv*
4116 sonymips mips-sony-*
4117 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4119 *** Changes in GDB 6.1.1:
4121 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4123 The TUI (Text-mode User Interface) is now built as part of a default
4124 GDB configuration. It is enabled by either selecting the TUI with the
4125 command line option "-i=tui" or by running the separate "gdbtui"
4126 program. For more information on the TUI, see the manual "Debugging
4129 * Pending breakpoint support (also included in GDB 6.1)
4131 Support has been added to allow you to specify breakpoints in shared
4132 libraries that have not yet been loaded. If a breakpoint location
4133 cannot be found, and the "breakpoint pending" option is set to auto,
4134 GDB queries you if you wish to make the breakpoint pending on a future
4135 shared-library load. If and when GDB resolves the breakpoint symbol,
4136 the pending breakpoint is removed as one or more regular breakpoints
4139 Pending breakpoints are very useful for GCJ Java debugging.
4141 * Fixed ISO-C build problems
4143 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4144 non ISO-C code that stopped them being built using a more strict ISO-C
4145 compiler (e.g., IBM's C compiler).
4147 * Fixed build problem on IRIX 5
4149 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4150 wasn't able to compile compile on an IRIX 5 system.
4152 * Added execute permission to gdb/gdbserver/configure
4154 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4155 permission. This bug would cause configure to fail on a number of
4156 systems (Solaris, IRIX). Ref: server/519.
4158 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4160 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4161 has been updated to use constant array sizes.
4163 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4165 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4166 its generated DWARF Call Frame Info. This encoding was causing GDB to
4167 panic, that panic has been fixed. Ref: gdb/1628.
4169 * Fixed a problem when examining parameters in shared library code.
4171 When examining parameters in optimized shared library code generated
4172 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4173 not available''. GDB now correctly displays the variable's value.
4175 *** Changes in GDB 6.1:
4177 * Removed --with-mmalloc
4179 Support for the mmalloc memory manager has been removed, as it
4180 conflicted with the internal gdb byte cache.
4182 * Changes in AMD64 configurations
4184 The AMD64 target now includes the %cs and %ss registers. As a result
4185 the AMD64 remote protocol has changed; this affects the floating-point
4186 and SSE registers. If you rely on those registers for your debugging,
4187 you should upgrade gdbserver on the remote side.
4189 * Revised SPARC target
4191 The SPARC target has been completely revised, incorporating the
4192 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4193 support for LynxOS and SunOS 4 has been dropped. Calling functions
4194 from within GDB on operating systems with a non-executable stack
4195 (Solaris, OpenBSD) now works.
4199 GDB has a new C++ demangler which does a better job on the mangled
4200 names generated by current versions of g++. It also runs faster, so
4201 with this and other changes gdb should now start faster on large C++
4204 * DWARF 2 Location Expressions
4206 GDB support for location expressions has been extended to support function
4207 arguments and frame bases. Older versions of GDB could crash when they
4210 * C++ nested types and namespaces
4212 GDB's support for nested types and namespaces in C++ has been
4213 improved, especially if you use the DWARF 2 debugging format. (This
4214 is the default for recent versions of GCC on most platforms.)
4215 Specifically, if you have a class "Inner" defined within a class or
4216 namespace "Outer", then GDB realizes that the class's name is
4217 "Outer::Inner", not simply "Inner". This should greatly reduce the
4218 frequency of complaints about not finding RTTI symbols. In addition,
4219 if you are stopped at inside of a function defined within a namespace,
4220 GDB modifies its name lookup accordingly.
4222 * New native configurations
4224 NetBSD/amd64 x86_64-*-netbsd*
4225 OpenBSD/amd64 x86_64-*-openbsd*
4226 OpenBSD/alpha alpha*-*-openbsd*
4227 OpenBSD/sparc sparc-*-openbsd*
4228 OpenBSD/sparc64 sparc64-*-openbsd*
4230 * New debugging protocols
4232 M32R with SDI protocol m32r-*-elf*
4234 * "set prompt-escape-char" command deleted.
4236 The command "set prompt-escape-char" has been deleted. This command,
4237 and its very obscure effet on GDB's prompt, was never documented,
4238 tested, nor mentioned in the NEWS file.
4240 * OBSOLETE configurations and files
4242 Configurations that have been declared obsolete in this release have
4243 been commented out. Unless there is activity to revive these
4244 configurations, the next release of GDB will have their sources
4245 permanently REMOVED.
4247 Sun 3, running SunOS 3 m68*-*-sunos3*
4248 Sun 3, running SunOS 4 m68*-*-sunos4*
4249 Sun 2, running SunOS 3 m68000-*-sunos3*
4250 Sun 2, running SunOS 4 m68000-*-sunos4*
4251 Motorola 680x0 running LynxOS m68*-*-lynxos*
4252 AT&T 3b1/Unix pc m68*-att-*
4253 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4254 decstation mips-dec-* mips-little-*
4255 riscos mips-*-riscos* mips-*-sysv*
4256 sonymips mips-sony-*
4257 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4259 * REMOVED configurations and files
4261 SGI Irix-4.x mips-sgi-irix4 or iris4
4262 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4263 Z8000 simulator z8k-zilog-none or z8ksim
4264 Matsushita MN10200 w/simulator mn10200-*-*
4265 H8/500 simulator h8500-hitachi-hms or h8500hms
4266 HP/PA running BSD hppa*-*-bsd*
4267 HP/PA running OSF/1 hppa*-*-osf*
4268 HP/PA Pro target hppa*-*-pro*
4269 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4270 386BSD i[3456]86-*-bsd*
4271 Sequent family i[3456]86-sequent-sysv4*
4272 i[3456]86-sequent-sysv*
4273 i[3456]86-sequent-bsd*
4274 SPARC running LynxOS sparc-*-lynxos*
4275 SPARC running SunOS 4 sparc-*-sunos4*
4276 Tsqware Sparclet sparclet-*-*
4277 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4279 *** Changes in GDB 6.0:
4283 Support for debugging the Objective-C programming language has been
4284 integrated into GDB.
4286 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4288 DWARF 2's Call Frame Information makes available compiler generated
4289 information that more exactly describes the program's run-time stack.
4290 By using this information, GDB is able to provide more robust stack
4293 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4294 have been updated to use a new backtrace mechanism which includes
4295 DWARF 2 CFI support.
4299 GDB's remote protocol has been extended to include support for hosted
4300 file I/O (where the remote target uses GDB's file system). See GDB's
4301 remote protocol documentation for details.
4303 * All targets using the new architecture framework.
4305 All of GDB's targets have been updated to use the new internal
4306 architecture framework. The way is now open for future GDB releases
4307 to include cross-architecture native debugging support (i386 on amd64,
4310 * GNU/Linux's Thread Local Storage (TLS)
4312 GDB now includes support for for the GNU/Linux implementation of
4313 per-thread variables.
4315 * GNU/Linux's Native POSIX Thread Library (NPTL)
4317 GDB's thread code has been updated to work with either the new
4318 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4320 * Separate debug info.
4322 GDB, in conjunction with BINUTILS, now supports a mechanism for
4323 automatically loading debug information from a separate file. Instead
4324 of shipping full debug and non-debug versions of system libraries,
4325 system integrators can now instead ship just the stripped libraries
4326 and optional debug files.
4328 * DWARF 2 Location Expressions
4330 DWARF 2 Location Expressions allow the compiler to more completely
4331 describe the location of variables (even in optimized code) to the
4334 GDB now includes preliminary support for location expressions (support
4335 for DW_OP_piece is still missing).
4339 A number of long standing bugs that caused GDB to die while starting a
4340 Java application have been fixed. GDB's Java support is now
4341 considered "useable".
4343 * GNU/Linux support for fork, vfork, and exec.
4345 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4346 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4349 * GDB supports logging output to a file
4351 There are two new commands, "set logging" and "show logging", which can be
4352 used to capture GDB's output to a file.
4354 * The meaning of "detach" has changed for gdbserver
4356 The "detach" command will now resume the application, as documented. To
4357 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4360 * d10v, m68hc11 `regs' command deprecated
4362 The `info registers' command has been updated so that it displays the
4363 registers using a format identical to the old `regs' command.
4367 A new command, "maint set profile on/off", has been added. This command can
4368 be used to enable or disable profiling while running GDB, to profile a
4369 session or a set of commands. In addition there is a new configure switch,
4370 "--enable-profiling", which will cause GDB to be compiled with profiling
4371 data, for more informative profiling results.
4373 * Default MI syntax changed to "mi2".
4375 The default MI (machine interface) syntax, enabled by the command line
4376 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4377 "mi1", can be enabled by specifying the option "-i=mi1".
4379 Support for the original "mi0" syntax (included in GDB 5.0) has been
4382 Fix for gdb/192: removed extraneous space when displaying frame level.
4383 Fix for gdb/672: update changelist is now output in mi list format.
4384 Fix for gdb/702: a -var-assign that updates the value now shows up
4385 in a subsequent -var-update.
4387 * New native configurations.
4389 FreeBSD/amd64 x86_64-*-freebsd*
4391 * Multi-arched targets.
4393 HP/PA HPUX11 hppa*-*-hpux*
4394 Renesas M32R/D w/simulator m32r-*-elf*
4396 * OBSOLETE configurations and files
4398 Configurations that have been declared obsolete in this release have
4399 been commented out. Unless there is activity to revive these
4400 configurations, the next release of GDB will have their sources
4401 permanently REMOVED.
4403 Z8000 simulator z8k-zilog-none or z8ksim
4404 Matsushita MN10200 w/simulator mn10200-*-*
4405 H8/500 simulator h8500-hitachi-hms or h8500hms
4406 HP/PA running BSD hppa*-*-bsd*
4407 HP/PA running OSF/1 hppa*-*-osf*
4408 HP/PA Pro target hppa*-*-pro*
4409 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4410 Sequent family i[3456]86-sequent-sysv4*
4411 i[3456]86-sequent-sysv*
4412 i[3456]86-sequent-bsd*
4413 Tsqware Sparclet sparclet-*-*
4414 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4416 * REMOVED configurations and files
4419 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4420 IBM AIX PS/2 i[3456]86-*-aix
4421 i386 running Mach 3.0 i[3456]86-*-mach3*
4422 i386 running Mach i[3456]86-*-mach*
4423 i386 running OSF/1 i[3456]86-*osf1mk*
4424 HP/Apollo 68k Family m68*-apollo*-sysv*,
4426 m68*-hp-bsd*, m68*-hp-hpux*
4427 Argonaut Risc Chip (ARC) arc-*-*
4428 Mitsubishi D30V d30v-*-*
4429 Fujitsu FR30 fr30-*-elf*
4430 OS/9000 i[34]86-*-os9k
4431 I960 with MON960 i960-*-coff
4433 * MIPS $fp behavior changed
4435 The convenience variable $fp, for the MIPS, now consistently returns
4436 the address of the current frame's base. Previously, depending on the
4437 context, $fp could refer to either $sp or the current frame's base
4438 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4439 The GNU Source-Level Debugger''.
4441 *** Changes in GDB 5.3:
4443 * GNU/Linux shared library multi-threaded performance improved.
4445 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4446 `/proc', in preference to `ptrace' for memory reads. This may result
4447 in an improvement in the start-up time of multi-threaded, shared
4448 library applications when run under GDB. One GDB user writes: ``loads
4449 shared libs like mad''.
4451 * ``gdbserver'' now supports multi-threaded applications on some targets
4453 Support for debugging multi-threaded applications which use
4454 the GNU/Linux LinuxThreads package has been added for
4455 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4456 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4458 * GDB now supports C/C++ preprocessor macros.
4460 GDB now expands preprocessor macro invocations in C/C++ expressions,
4461 and provides various commands for showing macro definitions and how
4464 The new command `macro expand EXPRESSION' expands any macro
4465 invocations in expression, and shows the result.
4467 The new command `show macro MACRO-NAME' shows the definition of the
4468 macro named MACRO-NAME, and where it was defined.
4470 Most compilers don't include information about macros in the debugging
4471 information by default. In GCC 3.1, for example, you need to compile
4472 your program with the options `-gdwarf-2 -g3'. If the macro
4473 information is present in the executable, GDB will read it.
4475 * Multi-arched targets.
4477 DEC Alpha (partial) alpha*-*-*
4478 DEC VAX (partial) vax-*-*
4480 National Semiconductor NS32000 (partial) ns32k-*-*
4481 Motorola 68000 (partial) m68k-*-*
4482 Motorola MCORE mcore-*-*
4486 Fujitsu FRV architecture added by Red Hat frv*-*-*
4489 * New native configurations
4491 Alpha NetBSD alpha*-*-netbsd*
4492 SH NetBSD sh*-*-netbsdelf*
4493 MIPS NetBSD mips*-*-netbsd*
4494 UltraSPARC NetBSD sparc64-*-netbsd*
4496 * OBSOLETE configurations and files
4498 Configurations that have been declared obsolete in this release have
4499 been commented out. Unless there is activity to revive these
4500 configurations, the next release of GDB will have their sources
4501 permanently REMOVED.
4503 Mitsubishi D30V d30v-*-*
4504 OS/9000 i[34]86-*-os9k
4505 IBM AIX PS/2 i[3456]86-*-aix
4506 Fujitsu FR30 fr30-*-elf*
4507 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4508 Argonaut Risc Chip (ARC) arc-*-*
4509 i386 running Mach 3.0 i[3456]86-*-mach3*
4510 i386 running Mach i[3456]86-*-mach*
4511 i386 running OSF/1 i[3456]86-*osf1mk*
4512 HP/Apollo 68k Family m68*-apollo*-sysv*,
4514 m68*-hp-bsd*, m68*-hp-hpux*
4515 I960 with MON960 i960-*-coff
4517 * OBSOLETE languages
4519 CHILL, a Pascal like language used by telecommunications companies.
4521 * REMOVED configurations and files
4523 AMD 29k family via UDI a29k-amd-udi, udi29k
4524 A29K VxWorks a29k-*-vxworks
4525 AMD 29000 embedded, using EBMON a29k-none-none
4526 AMD 29000 embedded with COFF a29k-none-coff
4527 AMD 29000 embedded with a.out a29k-none-aout
4529 testsuite/gdb.hp/gdb.threads-hp/ directory
4531 * New command "set max-user-call-depth <nnn>"
4533 This command allows the user to limit the call depth of user-defined
4534 commands. The default is 1024.
4536 * Changes in FreeBSD/i386 native debugging.
4538 Support for the "generate-core-file" has been added.
4540 * New commands "dump", "append", and "restore".
4542 These commands allow data to be copied from target memory
4543 to a bfd-format or binary file (dump and append), and back
4544 from a file into memory (restore).
4546 * Improved "next/step" support on multi-processor Alpha Tru64.
4548 The previous single-step mechanism could cause unpredictable problems,
4549 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4550 of a software single-step mechanism prevents this.
4552 *** Changes in GDB 5.2.1:
4560 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4561 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4562 Fix, by Joel Brobecker imported from mainline.
4564 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4565 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4566 Fix, by Fred Fish, imported from mainline.
4568 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4569 Surprisingly enough, it works now.
4570 By Michal Ludvig, imported from mainline.
4572 i386 hardware watchpoint support:
4573 avoid misses on second run for some targets.
4574 By Pierre Muller, imported from mainline.
4576 *** Changes in GDB 5.2:
4578 * New command "set trust-readonly-sections on[off]".
4580 This command is a hint that tells gdb that read-only sections
4581 really are read-only (ie. that their contents will not change).
4582 In this mode, gdb will go to the object file rather than the
4583 target to read memory from read-only sections (such as ".text").
4584 This can be a significant performance improvement on some
4585 (notably embedded) targets.
4587 * New command "generate-core-file" (or "gcore").
4589 This new gdb command allows the user to drop a core file of the child
4590 process state at any time. So far it's been implemented only for
4591 GNU/Linux and Solaris, but should be relatively easily ported to other
4592 hosts. Argument is core file name (defaults to core.<pid>).
4594 * New command line option
4596 GDB now accepts --pid or -p followed by a process id.
4598 * Change in command line behavior -- corefiles vs. process ids.
4600 There is a subtle behavior in the way in which GDB handles
4601 command line arguments. The first non-flag argument is always
4602 a program to debug, but the second non-flag argument may either
4603 be a corefile or a process id. Previously, GDB would attempt to
4604 open the second argument as a corefile, and if that failed, would
4605 issue a superfluous error message and then attempt to attach it as
4606 a process. Now, if the second argument begins with a non-digit,
4607 it will be treated as a corefile. If it begins with a digit,
4608 GDB will attempt to attach it as a process, and if no such process
4609 is found, will then attempt to open it as a corefile.
4611 * Changes in ARM configurations.
4613 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4614 configuration is fully multi-arch.
4616 * New native configurations
4618 ARM NetBSD arm*-*-netbsd*
4619 x86 OpenBSD i[3456]86-*-openbsd*
4620 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4621 Sparc64 running FreeBSD sparc64-*-freebsd*
4625 Sanyo XStormy16 xstormy16-elf
4627 * OBSOLETE configurations and files
4629 Configurations that have been declared obsolete in this release have
4630 been commented out. Unless there is activity to revive these
4631 configurations, the next release of GDB will have their sources
4632 permanently REMOVED.
4634 AMD 29k family via UDI a29k-amd-udi, udi29k
4635 A29K VxWorks a29k-*-vxworks
4636 AMD 29000 embedded, using EBMON a29k-none-none
4637 AMD 29000 embedded with COFF a29k-none-coff
4638 AMD 29000 embedded with a.out a29k-none-aout
4640 testsuite/gdb.hp/gdb.threads-hp/ directory
4642 * REMOVED configurations and files
4644 TI TMS320C80 tic80-*-*
4646 PowerPC Solaris powerpcle-*-solaris*
4647 PowerPC Windows NT powerpcle-*-cygwin32
4648 PowerPC Netware powerpc-*-netware*
4649 Harris/CXUX m88k m88*-harris-cxux*
4650 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4651 ns32k-utek-sysv* ns32k-utek-*
4652 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4653 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4654 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4655 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4656 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4658 * Changes to command line processing
4660 The new `--args' feature can be used to specify command-line arguments
4661 for the inferior from gdb's command line.
4663 * Changes to key bindings
4665 There is a new `operate-and-get-next' function bound to `C-o'.
4667 *** Changes in GDB 5.1.1
4669 Fix compile problem on DJGPP.
4671 Fix a problem with floating-point registers on the i386 being
4674 Fix to stop GDB crashing on .debug_str debug info.
4676 Numerous documentation fixes.
4678 Numerous testsuite fixes.
4680 *** Changes in GDB 5.1:
4682 * New native configurations
4684 Alpha FreeBSD alpha*-*-freebsd*
4685 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4686 MIPS GNU/Linux mips*-*-linux*
4687 MIPS SGI Irix 6.x mips*-sgi-irix6*
4688 ia64 AIX ia64-*-aix*
4689 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4693 Motorola 68HC11 and 68HC12 m68hc11-elf
4695 UltraSparc running GNU/Linux sparc64-*-linux*
4697 * OBSOLETE configurations and files
4699 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4700 Harris/CXUX m88k m88*-harris-cxux*
4701 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4702 ns32k-utek-sysv* ns32k-utek-*
4703 TI TMS320C80 tic80-*-*
4705 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4706 PowerPC Solaris powerpcle-*-solaris*
4707 PowerPC Windows NT powerpcle-*-cygwin32
4708 PowerPC Netware powerpc-*-netware*
4709 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4710 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4711 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4712 Apple Macintosh (MPW) host N/A
4714 stuff.c (Program to stuff files into a specially prepared space in kdb)
4715 kdb-start.c (Main loop for the standalone kernel debugger)
4717 Configurations that have been declared obsolete in this release have
4718 been commented out. Unless there is activity to revive these
4719 configurations, the next release of GDB will have their sources
4720 permanently REMOVED.
4722 * REMOVED configurations and files
4724 Altos 3068 m68*-altos-*
4725 Convex c1-*-*, c2-*-*
4727 ARM RISCix arm-*-* (as host)
4731 * GDB has been converted to ISO C.
4733 GDB's source code has been converted to ISO C. In particular, the
4734 sources are fully protoized, and rely on standard headers being
4739 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4741 * The MI enabled by default.
4743 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4744 revised and enabled by default. Packages which use GDB as a debugging
4745 engine behind a UI or another front end are encouraged to switch to
4746 using the GDB/MI interface, instead of the old annotations interface
4747 which is now deprecated.
4749 * Support for debugging Pascal programs.
4751 GDB now includes support for debugging Pascal programs. The following
4752 main features are supported:
4754 - Pascal-specific data types such as sets;
4756 - automatic recognition of Pascal sources based on file-name
4759 - Pascal-style display of data types, variables, and functions;
4761 - a Pascal expression parser.
4763 However, some important features are not yet supported.
4765 - Pascal string operations are not supported at all;
4767 - there are some problems with boolean types;
4769 - Pascal type hexadecimal constants are not supported
4770 because they conflict with the internal variables format;
4772 - support for Pascal objects and classes is not full yet;
4774 - unlike Pascal, GDB is case-sensitive for symbol names.
4776 * Changes in completion.
4778 Commands such as `shell', `run' and `set args', which pass arguments
4779 to inferior programs, now complete on file names, similar to what
4780 users expect at the shell prompt.
4782 Commands which accept locations, such as `disassemble', `print',
4783 `breakpoint', `until', etc. now complete on filenames as well as
4784 program symbols. Thus, if you type "break foob TAB", and the source
4785 files linked into the programs include `foobar.c', that file name will
4786 be one of the candidates for completion. However, file names are not
4787 considered for completion after you typed a colon that delimits a file
4788 name from a name of a function in that file, as in "break foo.c:bar".
4790 `set demangle-style' completes on available demangling styles.
4792 * New platform-independent commands:
4794 It is now possible to define a post-hook for a command as well as a
4795 hook that runs before the command. For more details, see the
4796 documentation of `hookpost' in the GDB manual.
4798 * Changes in GNU/Linux native debugging.
4800 Support for debugging multi-threaded programs has been completely
4801 revised for all platforms except m68k and sparc. You can now debug as
4802 many threads as your system allows you to have.
4804 Attach/detach is supported for multi-threaded programs.
4806 Support for SSE registers was added for x86. This doesn't work for
4807 multi-threaded programs though.
4809 * Changes in MIPS configurations.
4811 Multi-arch support is enabled for all MIPS configurations.
4813 GDB can now be built as native debugger on SGI Irix 6.x systems for
4814 debugging n32 executables. (Debugging 64-bit executables is not yet
4817 * Unified support for hardware watchpoints in all x86 configurations.
4819 Most (if not all) native x86 configurations support hardware-assisted
4820 breakpoints and watchpoints in a unified manner. This support
4821 implements debug register sharing between watchpoints, which allows to
4822 put a virtually infinite number of watchpoints on the same address,
4823 and also supports watching regions up to 16 bytes with several debug
4826 The new maintenance command `maintenance show-debug-regs' toggles
4827 debugging print-outs in functions that insert, remove, and test
4828 watchpoints and hardware breakpoints.
4830 * Changes in the DJGPP native configuration.
4832 New command ``info dos sysinfo'' displays assorted information about
4833 the CPU, OS, memory, and DPMI server.
4835 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4836 display information about segment descriptors stored in GDT, LDT, and
4839 New commands ``info dos pde'' and ``info dos pte'' display entries
4840 from Page Directory and Page Tables (for now works with CWSDPMI only).
4841 New command ``info dos address-pte'' displays the Page Table entry for
4842 a given linear address.
4844 GDB can now pass command lines longer than 126 characters to the
4845 program being debugged (requires an update to the libdbg.a library
4846 which is part of the DJGPP development kit).
4848 DWARF2 debug info is now supported.
4850 It is now possible to `step' and `next' through calls to `longjmp'.
4852 * Changes in documentation.
4854 All GDB documentation was converted to GFDL, the GNU Free
4855 Documentation License.
4857 Tracepoints-related commands are now fully documented in the GDB
4860 TUI, the Text-mode User Interface, is now documented in the manual.
4862 Tracepoints-related commands are now fully documented in the GDB
4865 The "GDB Internals" manual now has an index. It also includes
4866 documentation of `ui_out' functions, GDB coding standards, x86
4867 hardware watchpoints, and memory region attributes.
4869 * GDB's version number moved to ``version.in''
4871 The Makefile variable VERSION has been replaced by the file
4872 ``version.in''. People creating GDB distributions should update the
4873 contents of this file.
4877 GUD support is now a standard part of the EMACS distribution.
4879 *** Changes in GDB 5.0:
4881 * Improved support for debugging FP programs on x86 targets
4883 Unified and much-improved support for debugging floating-point
4884 programs on all x86 targets. In particular, ``info float'' now
4885 displays the FP registers in the same format on all x86 targets, with
4886 greater level of detail.
4888 * Improvements and bugfixes in hardware-assisted watchpoints
4890 It is now possible to watch array elements, struct members, and
4891 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4892 on x86 targets no longer erroneously trigger when the address is
4895 * Improvements in the native DJGPP version of GDB
4897 The distribution now includes all the scripts and auxiliary files
4898 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4899 machines ``out of the box''.
4901 The DJGPP version can now debug programs that use signals. It is
4902 possible to catch signals that happened in the debuggee, deliver
4903 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4904 would kill the program being debugged.) Programs that hook hardware
4905 interrupts (keyboard, timer, etc.) can also be debugged.
4907 It is now possible to debug DJGPP programs that redirect their
4908 standard handles or switch them to raw (as opposed to cooked) mode, or
4909 even close them. The command ``run < foo > bar'' works as expected,
4910 and ``info terminal'' reports useful information about the debuggee's
4911 terminal, including raw/cooked mode, redirection, etc.
4913 The DJGPP version now uses termios functions for console I/O, which
4914 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4917 DOS-style file names with drive letters are now fully supported by
4920 It is now possible to debug DJGPP programs that switch their working
4921 directory. It is also possible to rerun the debuggee any number of
4922 times without restarting GDB; thus, you can use the same setup,
4923 breakpoints, etc. for many debugging sessions.
4925 * New native configurations
4927 ARM GNU/Linux arm*-*-linux*
4928 PowerPC GNU/Linux powerpc-*-linux*
4932 Motorola MCore mcore-*-*
4933 x86 VxWorks i[3456]86-*-vxworks*
4934 PowerPC VxWorks powerpc-*-vxworks*
4935 TI TMS320C80 tic80-*-*
4937 * OBSOLETE configurations
4939 Altos 3068 m68*-altos-*
4940 Convex c1-*-*, c2-*-*
4942 ARM RISCix arm-*-* (as host)
4945 Configurations that have been declared obsolete will be commented out,
4946 but the code will be left in place. If there is no activity to revive
4947 these configurations before the next release of GDB, the sources will
4948 be permanently REMOVED.
4950 * Gould support removed
4952 Support for the Gould PowerNode and NP1 has been removed.
4954 * New features for SVR4
4956 On SVR4 native platforms (such as Solaris), if you attach to a process
4957 without first loading a symbol file, GDB will now attempt to locate and
4958 load symbols from the running process's executable file.
4960 * Many C++ enhancements
4962 C++ support has been greatly improved. Overload resolution now works properly
4963 in almost all cases. RTTI support is on the way.
4965 * Remote targets can connect to a sub-program
4967 A popen(3) style serial-device has been added. This device starts a
4968 sub-process (such as a stand-alone simulator) and then communicates
4969 with that. The sub-program to run is specified using the syntax
4970 ``|<program> <args>'' vis:
4972 (gdb) set remotedebug 1
4973 (gdb) target extended-remote |mn10300-elf-sim program-args
4975 * MIPS 64 remote protocol
4977 A long standing bug in the mips64 remote protocol where by GDB
4978 expected certain 32 bit registers (ex SR) to be transfered as 32
4979 instead of 64 bits has been fixed.
4981 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4982 added to provide backward compatibility with older versions of GDB.
4984 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4986 The command ``set remotebinarydownload'' command has been replaced by
4987 ``set remote X-packet''. Other commands in ``set remote'' family
4988 include ``set remote P-packet''.
4990 * Breakpoint commands accept ranges.
4992 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4993 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4994 ``tracepoint passcount'' also accepts a range of tracepoints.
4996 * ``apropos'' command added.
4998 The ``apropos'' command searches through command names and
4999 documentation strings, printing out matches, making it much easier to
5000 try to find a command that does what you are looking for.
5004 A new machine oriented interface (MI) has been added to GDB. This
5005 interface is designed for debug environments running GDB as a separate
5006 process. This is part of the long term libGDB project. See the
5007 "GDB/MI" chapter of the GDB manual for further information. It can be
5008 enabled by configuring with:
5010 .../configure --enable-gdbmi
5012 *** Changes in GDB-4.18:
5014 * New native configurations
5016 HP-UX 10.20 hppa*-*-hpux10.20
5017 HP-UX 11.x hppa*-*-hpux11.0*
5018 M68K GNU/Linux m68*-*-linux*
5022 Fujitsu FR30 fr30-*-elf*
5023 Intel StrongARM strongarm-*-*
5024 Mitsubishi D30V d30v-*-*
5026 * OBSOLETE configurations
5028 Gould PowerNode, NP1 np1-*-*, pn-*-*
5030 Configurations that have been declared obsolete will be commented out,
5031 but the code will be left in place. If there is no activity to revive
5032 these configurations before the next release of GDB, the sources will
5033 be permanently REMOVED.
5037 As a compatibility experiment, GDB's source files buildsym.h and
5038 buildsym.c have been converted to pure standard C, no longer
5039 containing any K&R compatibility code. We believe that all systems in
5040 use today either come with a standard C compiler, or have a GCC port
5041 available. If this is not true, please report the affected
5042 configuration to bug-gdb@gnu.org immediately. See the README file for
5043 information about getting a standard C compiler if you don't have one
5048 GDB now uses readline 2.2.
5050 * set extension-language
5052 You can now control the mapping between filename extensions and source
5053 languages by using the `set extension-language' command. For instance,
5054 you can ask GDB to treat .c files as C++ by saying
5055 set extension-language .c c++
5056 The command `info extensions' lists all of the recognized extensions
5057 and their associated languages.
5059 * Setting processor type for PowerPC and RS/6000
5061 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5062 you can use the `set processor' command to specify what variant of the
5063 PowerPC family you are debugging. The command
5067 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5068 following PowerPC and RS6000 variants:
5070 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5071 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5073 403GC IBM PowerPC 403GC
5074 505 Motorola PowerPC 505
5075 860 Motorola PowerPC 860 or 850
5076 601 Motorola PowerPC 601
5077 602 Motorola PowerPC 602
5078 603 Motorola/IBM PowerPC 603 or 603e
5079 604 Motorola PowerPC 604 or 604e
5080 750 Motorola/IBM PowerPC 750 or 750
5082 At the moment, this command just tells GDB what to name the
5083 special-purpose processor registers. Since almost all the affected
5084 registers are inaccessible to user-level programs, this command is
5085 only useful for remote debugging in its present form.
5089 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5090 more extensive support for HP-UX. Added features include shared
5091 library support, kernel threads and hardware watchpoints for 11.00,
5092 support for HP's ANSI C and C++ compilers, and a compatibility mode
5093 for xdb and dbx commands.
5097 HP's donation includes the new concept of catchpoints, which is a
5098 generalization of the old catch command. On HP-UX, it is now possible
5099 to catch exec, fork, and vfork, as well as library loading.
5101 This means that the existing catch command has changed; its first
5102 argument now specifies the type of catch to be set up. See the
5103 output of "help catch" for a list of catchpoint types.
5105 * Debugging across forks
5107 On HP-UX, you can choose which process to debug when a fork() happens
5112 HP has donated a curses-based terminal user interface (TUI). To get
5113 it, build with --enable-tui. Although this can be enabled for any
5114 configuration, at present it only works for native HP debugging.
5116 * GDB remote protocol additions
5118 A new protocol packet 'X' that writes binary data is now available.
5119 Default behavior is to try 'X', then drop back to 'M' if the stub
5120 fails to respond. The settable variable `remotebinarydownload'
5121 allows explicit control over the use of 'X'.
5123 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5124 full 64-bit address. The command
5126 set remoteaddresssize 32
5128 can be used to revert to the old behaviour. For existing remote stubs
5129 the change should not be noticed, as the additional address information
5132 In order to assist in debugging stubs, you may use the maintenance
5133 command `packet' to send any text string to the stub. For instance,
5135 maint packet heythere
5137 sends the packet "$heythere#<checksum>". Note that it is very easy to
5138 disrupt a debugging session by sending the wrong packet at the wrong
5141 The compare-sections command allows you to compare section data on the
5142 target to what is in the executable file without uploading or
5143 downloading, by comparing CRC checksums.
5145 * Tracing can collect general expressions
5147 You may now collect general expressions at tracepoints. This requires
5148 further additions to the target-side stub; see tracepoint.c and
5149 doc/agentexpr.texi for further details.
5151 * mask-address variable for Mips
5153 For Mips targets, you may control the zeroing of the upper 32 bits of
5154 a 64-bit address by entering `set mask-address on'. This is mainly
5155 of interest to users of embedded R4xxx and R5xxx processors.
5157 * Higher serial baud rates
5159 GDB's serial code now allows you to specify baud rates 57600, 115200,
5160 230400, and 460800 baud. (Note that your host system may not be able
5161 to achieve all of these rates.)
5165 The i960 configuration now includes an initial implementation of a
5166 builtin simulator, contributed by Jim Wilson.
5169 *** Changes in GDB-4.17:
5171 * New native configurations
5173 Alpha GNU/Linux alpha*-*-linux*
5174 Unixware 2.x i[3456]86-unixware2*
5175 Irix 6.x mips*-sgi-irix6*
5176 PowerPC GNU/Linux powerpc-*-linux*
5177 PowerPC Solaris powerpcle-*-solaris*
5178 Sparc GNU/Linux sparc-*-linux*
5179 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5183 Argonaut Risc Chip (ARC) arc-*-*
5184 Hitachi H8/300S h8300*-*-*
5185 Matsushita MN10200 w/simulator mn10200-*-*
5186 Matsushita MN10300 w/simulator mn10300-*-*
5187 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5188 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5189 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5190 Mitsubishi D10V w/simulator d10v-*-*
5191 Mitsubishi M32R/D w/simulator m32r-*-elf*
5192 Tsqware Sparclet sparclet-*-*
5193 NEC V850 w/simulator v850-*-*
5195 * New debugging protocols
5197 ARM with RDI protocol arm*-*-*
5198 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5199 DDB and LSI variants of PMON protocol mips*-*-*
5200 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5201 PowerPC with SDS protocol powerpc{,le}-*-eabi
5202 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5206 All configurations can now understand and use the DWARF 2 debugging
5207 format. The choice is automatic, if the symbol file contains DWARF 2
5212 GDB now includes basic Java language support. This support is
5213 only useful with Java compilers that produce native machine code.
5215 * solib-absolute-prefix and solib-search-path
5217 For SunOS and SVR4 shared libraries, you may now set the prefix for
5218 loading absolute shared library symbol files, and the search path for
5219 locating non-absolute shared library symbol files.
5221 * Live range splitting
5223 GDB can now effectively debug code for which GCC has performed live
5224 range splitting as part of its optimization. See gdb/doc/LRS for
5225 more details on the expected format of the stabs information.
5229 GDB's support for the GNU Hurd, including thread debugging, has been
5230 updated to work with current versions of the Hurd.
5234 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5235 instruction set. ARM GDB automatically detects when Thumb
5236 instructions are in use, and adjusts disassembly and backtracing
5241 GDB's MIPS target configurations now handle the MIP16 16-bit
5246 GDB now includes support for overlays; if an executable has been
5247 linked such that multiple sections are based at the same address, GDB
5248 will decide which section to use for symbolic info. You can choose to
5249 control the decision manually, using overlay commands, or implement
5250 additional target-side support and use "overlay load-target" to bring
5251 in the overlay mapping. Do "help overlay" for more detail.
5255 The command "info symbol <address>" displays information about
5256 the symbol at the specified address.
5260 The standard remote protocol now includes an extension that allows
5261 asynchronous collection and display of trace data. This requires
5262 extensive support in the target-side debugging stub. Tracing mode
5263 includes a new interaction mode in GDB and new commands: see the
5264 file tracepoint.c for more details.
5268 Configurations for embedded MIPS now include a simulator contributed
5269 by Cygnus Solutions. The simulator supports the instruction sets
5270 of most MIPS variants.
5274 Sparc configurations may now include the ERC32 simulator contributed
5275 by the European Space Agency. The simulator is not built into
5276 Sparc targets by default; configure with --enable-sim to include it.
5280 For target configurations that may include multiple variants of a
5281 basic architecture (such as MIPS and SH), you may now set the
5282 architecture explicitly. "set arch" sets, "info arch" lists
5283 the possible architectures.
5285 *** Changes in GDB-4.16:
5287 * New native configurations
5289 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5290 M68K NetBSD m68k-*-netbsd*
5291 PowerPC AIX 4.x powerpc-*-aix*
5292 PowerPC MacOS powerpc-*-macos*
5293 PowerPC Windows NT powerpcle-*-cygwin32
5294 RS/6000 AIX 4.x rs6000-*-aix4*
5298 ARM with RDP protocol arm-*-*
5299 I960 with MON960 i960-*-coff
5300 MIPS VxWorks mips*-*-vxworks*
5301 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5302 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5304 Matra Sparclet sparclet-*-*
5308 The powerpc-eabi configuration now includes the PSIM simulator,
5309 contributed by Andrew Cagney, with assistance from Mike Meissner.
5310 PSIM is a very elaborate model of the PowerPC, including not only
5311 basic instruction set execution, but also details of execution unit
5312 performance and I/O hardware. See sim/ppc/README for more details.
5316 GDB now works with Solaris 2.5.
5318 * Windows 95/NT native
5320 GDB will now work as a native debugger on Windows 95 and Windows NT.
5321 To build it from source, you must use the "gnu-win32" environment,
5322 which uses a DLL to emulate enough of Unix to run the GNU tools.
5323 Further information, binaries, and sources are available at
5324 ftp.cygnus.com, under pub/gnu-win32.
5326 * dont-repeat command
5328 If a user-defined command includes the command `dont-repeat', then the
5329 command will not be repeated if the user just types return. This is
5330 useful if the command is time-consuming to run, so that accidental
5331 extra keystrokes don't run the same command many times.
5333 * Send break instead of ^C
5335 The standard remote protocol now includes an option to send a break
5336 rather than a ^C to the target in order to interrupt it. By default,
5337 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5339 * Remote protocol timeout
5341 The standard remote protocol includes a new variable `remotetimeout'
5342 that allows you to set the number of seconds before GDB gives up trying
5343 to read from the target. The default value is 2.
5345 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5347 By default GDB will automatically keep track of objects as they are
5348 loaded and unloaded by the dynamic linker. By using the command `set
5349 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5350 when shared library events occur, thus allowing you to set breakpoints
5351 in shared libraries which are explicitly loaded by the inferior.
5353 Note this feature does not work on hpux8. On hpux9 you must link
5354 /usr/lib/end.o into your program. This feature should work
5355 automatically on hpux10.
5357 * Irix 5.x hardware watchpoint support
5359 Irix 5 configurations now support the use of hardware watchpoints.
5361 * Mips protocol "SYN garbage limit"
5363 When debugging a Mips target using the `target mips' protocol, you
5364 may set the number of characters that GDB will ignore by setting
5365 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5366 every character. The default value is 1050.
5368 * Recording and replaying remote debug sessions
5370 If you set `remotelogfile' to the name of a file, gdb will write to it
5371 a recording of a remote debug session. This recording may then be
5372 replayed back to gdb using "gdbreplay". See gdbserver/README for
5373 details. This is useful when you have a problem with GDB while doing
5374 remote debugging; you can make a recording of the session and send it
5375 to someone else, who can then recreate the problem.
5377 * Speedups for remote debugging
5379 GDB includes speedups for downloading and stepping MIPS systems using
5380 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5381 and more efficient S-record downloading.
5383 * Memory use reductions and statistics collection
5385 GDB now uses less memory and reports statistics about memory usage.
5386 Try the `maint print statistics' command, for example.
5388 *** Changes in GDB-4.15:
5390 * Psymtabs for XCOFF
5392 The symbol reader for AIX GDB now uses partial symbol tables. This
5393 can greatly improve startup time, especially for large executables.
5395 * Remote targets use caching
5397 Remote targets now use a data cache to speed up communication with the
5398 remote side. The data cache could lead to incorrect results because
5399 it doesn't know about volatile variables, thus making it impossible to
5400 debug targets which use memory mapped I/O devices. `set remotecache
5401 off' turns the the data cache off.
5403 * Remote targets may have threads
5405 The standard remote protocol now includes support for multiple threads
5406 in the target system, using new protocol commands 'H' and 'T'. See
5407 gdb/remote.c for details.
5411 If GDB is configured with `--enable-netrom', then it will include
5412 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5413 acts as though it is a bank of ROM on the target board, but you can
5414 write into it over the network. GDB's support consists only of
5415 support for fast loading into the emulated ROM; to debug, you must use
5416 another protocol, such as standard remote protocol. The usual
5417 sequence is something like
5419 target nrom <netrom-hostname>
5421 target remote <netrom-hostname>:1235
5425 GDB now includes support for the Apple Macintosh, as a host only. It
5426 may be run as either an MPW tool or as a standalone application, and
5427 it can debug through the serial port. All the usual GDB commands are
5428 available, but to the target command, you must supply "serial" as the
5429 device type instead of "/dev/ttyXX". See mpw-README in the main
5430 directory for more information on how to build. The MPW configuration
5431 scripts */mpw-config.in support only a few targets, and only the
5432 mips-idt-ecoff target has been tested.
5436 GDB configuration now uses autoconf. This is not user-visible,
5437 but does simplify configuration and building.
5441 GDB now supports hpux10.
5443 *** Changes in GDB-4.14:
5445 * New native configurations
5447 x86 FreeBSD i[345]86-*-freebsd
5448 x86 NetBSD i[345]86-*-netbsd
5449 NS32k NetBSD ns32k-*-netbsd
5450 Sparc NetBSD sparc-*-netbsd
5454 A29K VxWorks a29k-*-vxworks
5455 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5456 CPU32 EST-300 emulator m68*-*-est*
5457 PowerPC ELF powerpc-*-elf
5460 * Alpha OSF/1 support for procfs
5462 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5463 possible to attach to running processes. As the mounting of the /proc
5464 filesystem is optional on the Alpha, GDB automatically determines
5465 the availability of /proc during startup. This can lead to problems
5466 if /proc is unmounted after GDB has been started.
5468 * Arguments to user-defined commands
5470 User commands may accept up to 10 arguments separated by whitespace.
5471 Arguments are accessed within the user command via $arg0..$arg9. A
5474 print $arg0 + $arg1 + $arg2
5476 To execute the command use:
5479 Defines the command "adder" which prints the sum of its three arguments.
5480 Note the arguments are text substitutions, so they may reference variables,
5481 use complex expressions, or even perform inferior function calls.
5483 * New `if' and `while' commands
5485 This makes it possible to write more sophisticated user-defined
5486 commands. Both commands take a single argument, which is the
5487 expression to evaluate, and must be followed by the commands to
5488 execute, one per line, if the expression is nonzero, the list being
5489 terminated by the word `end'. The `if' command list may include an
5490 `else' word, which causes the following commands to be executed only
5491 if the expression is zero.
5493 * Fortran source language mode
5495 GDB now includes partial support for Fortran 77. It will recognize
5496 Fortran programs and can evaluate a subset of Fortran expressions, but
5497 variables and functions may not be handled correctly. GDB will work
5498 with G77, but does not yet know much about symbols emitted by other
5501 * Better HPUX support
5503 Most debugging facilities now work on dynamic executables for HPPAs
5504 running hpux9 or later. You can attach to running dynamically linked
5505 processes, but by default the dynamic libraries will be read-only, so
5506 for instance you won't be able to put breakpoints in them. To change
5507 that behavior do the following before running the program:
5513 This will cause the libraries to be mapped private and read-write.
5514 To revert to the normal behavior, do this:
5520 You cannot set breakpoints or examine data in the library until after
5521 the library is loaded if the function/data symbols do not have
5524 GDB can now also read debug symbols produced by the HP C compiler on
5525 HPPAs (sorry, no C++, Fortran or 68k support).
5527 * Target byte order now dynamically selectable
5529 You can choose which byte order to use with a target system, via the
5530 commands "set endian big" and "set endian little", and you can see the
5531 current setting by using "show endian". You can also give the command
5532 "set endian auto", in which case GDB will use the byte order
5533 associated with the executable. Currently, only embedded MIPS
5534 configurations support dynamic selection of target byte order.
5536 * New DOS host serial code
5538 This version uses DPMI interrupts to handle buffered I/O, so you
5539 no longer need to run asynctsr when debugging boards connected to
5542 *** Changes in GDB-4.13:
5544 * New "complete" command
5546 This lists all the possible completions for the rest of the line, if it
5547 were to be given as a command itself. This is intended for use by emacs.
5549 * Trailing space optional in prompt
5551 "set prompt" no longer adds a space for you after the prompt you set. This
5552 allows you to set a prompt which ends in a space or one that does not.
5554 * Breakpoint hit counts
5556 "info break" now displays a count of the number of times the breakpoint
5557 has been hit. This is especially useful in conjunction with "ignore"; you
5558 can ignore a large number of breakpoint hits, look at the breakpoint info
5559 to see how many times the breakpoint was hit, then run again, ignoring one
5560 less than that number, and this will get you quickly to the last hit of
5563 * Ability to stop printing at NULL character
5565 "set print null-stop" will cause GDB to stop printing the characters of
5566 an array when the first NULL is encountered. This is useful when large
5567 arrays actually contain only short strings.
5569 * Shared library breakpoints
5571 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5572 breakpoints in shared libraries before the executable is run.
5574 * Hardware watchpoints
5576 There is a new hardware breakpoint for the watch command for sparclite
5577 targets. See gdb/sparclite/hw_breakpoint.note.
5579 Hardware watchpoints are also now supported under GNU/Linux.
5583 Annotations have been added. These are for use with graphical interfaces,
5584 and are still experimental. Currently only gdba.el uses these.
5586 * Improved Irix 5 support
5588 GDB now works properly with Irix 5.2.
5590 * Improved HPPA support
5592 GDB now works properly with the latest GCC and GAS.
5594 * New native configurations
5596 Sequent PTX4 i[34]86-sequent-ptx4
5597 HPPA running OSF/1 hppa*-*-osf*
5598 Atari TT running SVR4 m68*-*-sysv4*
5599 RS/6000 LynxOS rs6000-*-lynxos*
5603 OS/9000 i[34]86-*-os9k
5604 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5607 * Hitachi SH7000 and E7000-PC ICE support
5609 There is now support for communicating with the Hitachi E7000-PC ICE.
5610 This is available automatically when GDB is configured for the SH.
5614 As usual, a variety of small fixes and improvements, both generic
5615 and configuration-specific. See the ChangeLog for more detail.
5617 *** Changes in GDB-4.12:
5619 * Irix 5 is now supported
5623 GDB-4.12 on the HPPA has a number of changes which make it unable
5624 to debug the output from the currently released versions of GCC and
5625 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5626 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5627 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5630 *** Changes in GDB-4.11:
5632 * User visible changes:
5636 The "set remotedebug" option is now consistent between the mips remote
5637 target, remote targets using the gdb-specific protocol, UDI (AMD's
5638 debug protocol for the 29k) and the 88k bug monitor. It is now an
5639 integer specifying a debug level (normally 0 or 1, but 2 means more
5640 debugging info for the mips target).
5642 * DEC Alpha native support
5644 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5645 debug info, but GDB works fairly well with the DEC compiler and should
5646 work with a future GCC release. See the README file for a few
5647 Alpha-specific notes.
5649 * Preliminary thread implementation
5651 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5653 * LynxOS native and target support for 386
5655 This release has been hosted on LynxOS 2.2, and also can be configured
5656 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5659 * Improvements in C++ mangling/demangling.
5661 This release has much better g++ debugging, specifically in name
5662 mangling/demangling, virtual function calls, print virtual table,
5663 call methods, ...etc.
5665 *** Changes in GDB-4.10:
5667 * User visible changes:
5669 Remote debugging using the GDB-specific (`target remote') protocol now
5670 supports the `load' command. This is only useful if you have some
5671 other way of getting the stub to the target system, and you can put it
5672 somewhere in memory where it won't get clobbered by the download.
5674 Filename completion now works.
5676 When run under emacs mode, the "info line" command now causes the
5677 arrow to point to the line specified. Also, "info line" prints
5678 addresses in symbolic form (as well as hex).
5680 All vxworks based targets now support a user settable option, called
5681 vxworks-timeout. This option represents the number of seconds gdb
5682 should wait for responses to rpc's. You might want to use this if
5683 your vxworks target is, perhaps, a slow software simulator or happens
5684 to be on the far side of a thin network line.
5688 This release contains support for using a DEC alpha as a GDB host for
5689 cross debugging. Native alpha debugging is not supported yet.
5692 *** Changes in GDB-4.9:
5696 This is the first GDB release which is accompanied by a matching testsuite.
5697 The testsuite requires installation of dejagnu, which should be available
5698 via ftp from most sites that carry GNU software.
5702 'Cfront' style demangling has had its name changed to 'ARM' style, to
5703 emphasize that it was written from the specifications in the C++ Annotated
5704 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5705 disclaimers, it still generated too much confusion with users attempting to
5706 use gdb with AT&T cfront.
5710 GDB now uses a standard remote interface to a simulator library.
5711 So far, the library contains simulators for the Zilog Z8001/2, the
5712 Hitachi H8/300, H8/500 and Super-H.
5714 * New targets supported
5716 H8/300 simulator h8300-hitachi-hms or h8300hms
5717 H8/500 simulator h8500-hitachi-hms or h8500hms
5718 SH simulator sh-hitachi-hms or sh
5719 Z8000 simulator z8k-zilog-none or z8ksim
5720 IDT MIPS board over serial line mips-idt-ecoff
5722 Cross-debugging to GO32 targets is supported. It requires a custom
5723 version of the i386-stub.c module which is integrated with the
5724 GO32 memory extender.
5726 * New remote protocols
5728 MIPS remote debugging protocol.
5730 * New source languages supported
5732 This version includes preliminary support for Chill, a Pascal like language
5733 used by telecommunications companies. Chill support is also being integrated
5734 into the GNU compiler, but we don't know when it will be publically available.
5737 *** Changes in GDB-4.8:
5739 * HP Precision Architecture supported
5741 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5742 version of this support was available as a set of patches from the
5743 University of Utah. GDB does not support debugging of programs
5744 compiled with the HP compiler, because HP will not document their file
5745 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5746 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5748 Many problems in the preliminary version have been fixed.
5750 * Faster and better demangling
5752 We have improved template demangling and fixed numerous bugs in the GNU style
5753 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5754 character types (wchar_t) are now supported. Demangling of each symbol is now
5755 only done once, and is cached when the symbol table for a file is read in.
5756 This results in a small increase in memory usage for C programs, a moderate
5757 increase in memory usage for C++ programs, and a fantastic speedup in
5760 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5761 from the specifications in the Annotated Reference Manual, which AT&T's
5762 compiler does not actually implement.
5764 * G++ multiple inheritance compiler problem
5766 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5767 inheritance lattices was reworked to properly discover ambiguities. We
5768 recently found an example which causes this new algorithm to fail in a
5769 very subtle way, producing bad debug information for those classes.
5770 The file 'gcc.patch' (in this directory) can be applied to gcc to
5771 circumvent the problem. A future GCC release will contain a complete
5774 The previous G++ debug info problem (mentioned below for the gdb-4.7
5775 release) is fixed in gcc version 2.3.2.
5777 * Improved configure script
5779 The `configure' script will now attempt to guess your system type if
5780 you don't supply a host system type. The old scheme of supplying a
5781 host system triplet is preferable over using this. All the magic is
5782 done in the new `config.guess' script. Examine it for details.
5784 We have also brought our configure script much more in line with the FSF's
5785 version. It now supports the --with-xxx options. In particular,
5786 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5787 The resulting GDB will not be able to read arbitrary object file formats --
5788 only the format ``expected'' to be used on the configured target system.
5789 We hope to make this the default in a future release.
5791 * Documentation improvements
5793 There's new internal documentation on how to modify GDB, and how to
5794 produce clean changes to the code. We implore people to read it
5795 before submitting changes.
5797 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5798 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5799 `info' files are also provided. To build `info' files from scratch,
5800 you will need the latest `makeinfo' release, which will be available in
5801 a future texinfo-X.Y release.
5803 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5804 We're not sure exactly which versions have this problem, but it has
5805 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5806 or better. If that isn't possible, there is a patch in
5807 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5808 around this problem.
5812 GDB now supports array constants that can be used in expressions typed in by
5813 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5814 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5817 The new directory `gdb/sparclite' contains a program that demonstrates
5818 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5820 * New native hosts supported
5822 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5823 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5825 * New targets supported
5827 AMD 29k family via UDI a29k-amd-udi or udi29k
5829 * New file formats supported
5831 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5832 HPUX core files, and SCO 3.2v2 core files.
5836 Attaching to processes now works again; thanks for the many bug reports.
5838 We have also stomped on a bunch of core dumps caused by
5839 printf_filtered("%s") problems.
5841 We eliminated a copyright problem on the rpc and ptrace header files
5842 for VxWorks, which was discovered at the last minute during the 4.7
5843 release. You should now be able to build a VxWorks GDB.
5845 You can now interrupt gdb while an attached process is running. This
5846 will cause the attached process to stop, and give control back to GDB.
5848 We fixed problems caused by using too many file descriptors
5849 for reading symbols from object files and libraries. This was
5850 especially a problem for programs that used many (~100) shared
5853 The `step' command now only enters a subroutine if there is line number
5854 information for the subroutine. Otherwise it acts like the `next'
5855 command. Previously, `step' would enter subroutines if there was
5856 any debugging information about the routine. This avoids problems
5857 when using `cc -g1' on MIPS machines.
5859 * Internal improvements
5861 GDB's internal interfaces have been improved to make it easier to support
5862 debugging of multiple languages in the future.
5864 GDB now uses a common structure for symbol information internally.
5865 Minimal symbols (derived from linkage symbols in object files), partial
5866 symbols (from a quick scan of debug information), and full symbols
5867 contain a common subset of information, making it easier to write
5868 shared code that handles any of them.
5870 * New command line options
5872 We now accept --silent as an alias for --quiet.
5876 The memory-mapped-malloc library is now licensed under the GNU Library
5877 General Public License.
5879 *** Changes in GDB-4.7:
5881 * Host/native/target split
5883 GDB has had some major internal surgery to untangle the support for
5884 hosts and remote targets. Now, when you configure GDB for a remote
5885 target, it will no longer load in all of the support for debugging
5886 local programs on the host. When fully completed and tested, this will
5887 ensure that arbitrary host/target combinations are possible.
5889 The primary conceptual shift is to separate the non-portable code in
5890 GDB into three categories. Host specific code is required any time GDB
5891 is compiled on that host, regardless of the target. Target specific
5892 code relates to the peculiarities of the target, but can be compiled on
5893 any host. Native specific code is everything else: it can only be
5894 built when the host and target are the same system. Child process
5895 handling and core file support are two common `native' examples.
5897 GDB's use of /proc for controlling Unix child processes is now cleaner.
5898 It has been split out into a single module under the `target_ops' vector,
5899 plus two native-dependent functions for each system that uses /proc.
5901 * New hosts supported
5903 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5904 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5905 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5907 * New targets supported
5909 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5910 68030 and CPU32 m68030-*-*, m68332-*-*
5912 * New native hosts supported
5914 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5915 (386bsd is not well tested yet)
5916 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5918 * New file formats supported
5920 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5921 supports reading of `a.out.adobe' object files, which are an a.out
5922 format extended with minimal information about multiple sections.
5926 `show copying' is the same as the old `info copying'.
5927 `show warranty' is the same as `info warrantee'.
5928 These were renamed for consistency. The old commands continue to work.
5930 `info handle' is a new alias for `info signals'.
5932 You can now define pre-command hooks, which attach arbitrary command
5933 scripts to any command. The commands in the hook will be executed
5934 prior to the user's command. You can also create a hook which will be
5935 executed whenever the program stops. See gdb.texinfo.
5939 We now deal with Cfront style name mangling, and can even extract type
5940 info from mangled symbols. GDB can automatically figure out which
5941 symbol mangling style your C++ compiler uses.
5943 Calling of methods and virtual functions has been improved as well.
5947 The crash that occured when debugging Sun Ansi-C compiled binaries is
5948 fixed. This was due to mishandling of the extra N_SO stabs output
5951 We also finally got Ultrix 4.2 running in house, and fixed core file
5952 support, with help from a dozen people on the net.
5954 John M. Farrell discovered that the reason that single-stepping was so
5955 slow on all of the Mips based platforms (primarily SGI and DEC) was
5956 that we were trying to demangle and lookup a symbol used for internal
5957 purposes on every instruction that was being stepped through. Changing
5958 the name of that symbol so that it couldn't be mistaken for a C++
5959 mangled symbol sped things up a great deal.
5961 Rich Pixley sped up symbol lookups in general by getting much smarter
5962 about when C++ symbol mangling is necessary. This should make symbol
5963 completion (TAB on the command line) much faster. It's not as fast as
5964 we'd like, but it's significantly faster than gdb-4.6.
5968 A new user controllable variable 'call_scratch_address' can
5969 specify the location of a scratch area to be used when GDB
5970 calls a function in the target. This is necessary because the
5971 usual method of putting the scratch area on the stack does not work
5972 in systems that have separate instruction and data spaces.
5974 We integrated changes to support the 29k UDI (Universal Debugger
5975 Interface), but discovered at the last minute that we didn't have all
5976 of the appropriate copyright paperwork. We are working with AMD to
5977 resolve this, and hope to have it available soon.
5981 We have sped up the remote serial line protocol, especially for targets
5982 with lots of registers. It now supports a new `expedited status' ('T')
5983 message which can be used in place of the existing 'S' status message.
5984 This allows the remote stub to send only the registers that GDB
5985 needs to make a quick decision about single-stepping or conditional
5986 breakpoints, eliminating the need to fetch the entire register set for
5987 each instruction being stepped through.
5989 The GDB remote serial protocol now implements a write-through cache for
5990 registers, only re-reading the registers if the target has run.
5992 There is also a new remote serial stub for SPARC processors. You can
5993 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5994 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5995 processor with a serial port.
5999 Configure.in files have become much easier to read and modify. A new
6000 `table driven' format makes it more obvious what configurations are
6001 supported, and what files each one uses.
6005 There is a new opcodes library which will eventually contain all of the
6006 disassembly routines and opcode tables. At present, it only contains
6007 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6008 disassembler (binutils/objdump) to share these routines.
6010 The libiberty library is now copylefted under the GNU Library General
6011 Public License. This allows more liberal use, and was done so libg++
6012 can use it. This makes no difference to GDB, since the Library License
6013 grants all the rights from the General Public License.
6017 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6018 reference to the stabs symbol info used by the debugger. It is (as far
6019 as we know) the only published document on this fascinating topic. We
6020 encourage you to read it, compare it to the stabs information on your
6021 system, and send improvements on the document in general (to
6022 bug-gdb@prep.ai.mit.edu).
6024 And, of course, many bugs have been fixed.
6027 *** Changes in GDB-4.6:
6029 * Better support for C++ function names
6031 GDB now accepts as input the "demangled form" of C++ overloaded function
6032 names and member function names, and can do command completion on such names
6033 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6034 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6035 Make use of command completion, it is your friend.
6037 GDB also now accepts a variety of C++ mangled symbol formats. They are
6038 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6039 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6040 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6041 for the list of formats.
6043 * G++ symbol mangling problem
6045 Recent versions of gcc have a bug in how they emit debugging information for
6046 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6047 directory) can be applied to gcc to fix the problem. Alternatively, if you
6048 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6049 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6050 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6053 * New 'maintenance' command
6055 All of the commands related to hacking GDB internals have been moved out of
6056 the main command set, and now live behind the 'maintenance' command. This
6057 can also be abbreviated as 'mt'. The following changes were made:
6059 dump-me -> maintenance dump-me
6060 info all-breakpoints -> maintenance info breakpoints
6061 printmsyms -> maintenance print msyms
6062 printobjfiles -> maintenance print objfiles
6063 printpsyms -> maintenance print psymbols
6064 printsyms -> maintenance print symbols
6066 The following commands are new:
6068 maintenance demangle Call internal GDB demangler routine to
6069 demangle a C++ link name and prints the result.
6070 maintenance print type Print a type chain for a given symbol
6072 * Change to .gdbinit file processing
6074 We now read the $HOME/.gdbinit file before processing the argv arguments
6075 (e.g. reading symbol files or core files). This allows global parameters to
6076 be set, which will apply during the symbol reading. The ./.gdbinit is still
6077 read after argv processing.
6079 * New hosts supported
6081 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6083 GNU/Linux support i386-unknown-linux or linux
6085 We are also including code to support the HP/PA running BSD and HPUX. This
6086 is almost guaranteed not to work, as we didn't have time to test or build it
6087 for this release. We are including it so that the more adventurous (or
6088 masochistic) of you can play with it. We also had major problems with the
6089 fact that the compiler that we got from HP doesn't support the -g option.
6092 * New targets supported
6094 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6096 * More smarts about finding #include files
6098 GDB now remembers the compilation directory for all include files, and for
6099 all files from which C is generated (like yacc and lex sources). This
6100 greatly improves GDB's ability to find yacc/lex sources, and include files,
6101 especially if you are debugging your program from a directory different from
6102 the one that contains your sources.
6104 We also fixed a bug which caused difficulty with listing and setting
6105 breakpoints in include files which contain C code. (In the past, you had to
6106 try twice in order to list an include file that you hadn't looked at before.)
6108 * Interesting infernals change
6110 GDB now deals with arbitrary numbers of sections, where the symbols for each
6111 section must be relocated relative to that section's landing place in the
6112 target's address space. This work was needed to support ELF with embedded
6113 stabs used by Solaris-2.0.
6115 * Bug fixes (of course!)
6117 There have been loads of fixes for the following things:
6118 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6119 i960, stabs, DOS(GO32), procfs, etc...
6121 See the ChangeLog for details.
6123 *** Changes in GDB-4.5:
6125 * New machines supported (host and target)
6127 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6129 SGI Irix-4.x mips-sgi-irix4 or iris4
6131 * New malloc package
6133 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6134 Mmalloc is capable of handling mutiple heaps of memory. It is also
6135 capable of saving a heap to a file, and then mapping it back in later.
6136 This can be used to greatly speedup the startup of GDB by using a
6137 pre-parsed symbol table which lives in a mmalloc managed heap. For
6138 more details, please read mmalloc/mmalloc.texi.
6142 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6143 'help info proc' for details.
6145 * MIPS ecoff symbol table format
6147 The code that reads MIPS symbol table format is now supported on all hosts.
6148 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6151 * File name changes for MS-DOS
6153 Many files in the config directories have been renamed to make it easier to
6154 support GDB on MS-DOSe systems (which have very restrictive file name
6155 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6156 environment) is close to working but has some remaining problems. Note
6157 that debugging of DOS programs is not supported, due to limitations
6158 in the ``operating system'', but it can be used to host cross-debugging.
6160 * Cross byte order fixes
6162 Many fixes have been made to support cross debugging of Sparc and MIPS
6163 targets from hosts whose byte order differs.
6165 * New -mapped and -readnow options
6167 If memory-mapped files are available on your system through the 'mmap'
6168 system call, you can use the -mapped option on the `file' or
6169 `symbol-file' commands to cause GDB to write the symbols from your
6170 program into a reusable file. If the program you are debugging is
6171 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6172 Future GDB debugging sessions will notice the presence of this file,
6173 and will quickly map in symbol information from it, rather than reading
6174 the symbol table from the executable program. Using the '-mapped'
6175 option in a GDB `file' or `symbol-file' command has the same effect as
6176 starting GDB with the '-mapped' command-line option.
6178 You can cause GDB to read the entire symbol table immediately by using
6179 the '-readnow' option with any of the commands that load symbol table
6180 information (or on the GDB command line). This makes the command
6181 slower, but makes future operations faster.
6183 The -mapped and -readnow options are typically combined in order to
6184 build a `fred.syms' file that contains complete symbol information.
6185 A simple GDB invocation to do nothing but build a `.syms' file for future
6188 gdb -batch -nx -mapped -readnow programname
6190 The `.syms' file is specific to the host machine on which GDB is run.
6191 It holds an exact image of GDB's internal symbol table. It cannot be
6192 shared across multiple host platforms.
6194 * longjmp() handling
6196 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6197 siglongjmp() without losing control. This feature has not yet been ported to
6198 all systems. It currently works on many 386 platforms, all MIPS-based
6199 platforms (SGI, DECstation, etc), and Sun3/4.
6203 Preliminary work has been put in to support the new Solaris OS from Sun. At
6204 this time, it can control and debug processes, but it is not capable of
6209 As always, many many bug fixes. The major areas were with g++, and mipsread.
6210 People using the MIPS-based platforms should experience fewer mysterious
6211 crashes and trashed symbol tables.
6213 *** Changes in GDB-4.4:
6215 * New machines supported (host and target)
6217 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6219 BSD Reno on Vax vax-dec-bsd
6220 Ultrix on Vax vax-dec-ultrix
6222 * New machines supported (target)
6224 AMD 29000 embedded, using EBMON a29k-none-none
6228 GDB continues to improve its handling of C++. `References' work better.
6229 The demangler has also been improved, and now deals with symbols mangled as
6230 per the Annotated C++ Reference Guide.
6232 GDB also now handles `stabs' symbol information embedded in MIPS
6233 `ecoff' symbol tables. Since the ecoff format was not easily
6234 extensible to handle new languages such as C++, this appeared to be a
6235 good way to put C++ debugging info into MIPS binaries. This option
6236 will be supported in the GNU C compiler, version 2, when it is
6239 * New features for SVR4
6241 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6242 shared libraries. Debugging dynamically linked programs should present
6243 only minor differences from debugging statically linked programs.
6245 The `info proc' command will print out information about any process
6246 on an SVR4 system (including the one you are debugging). At the moment,
6247 it prints the address mappings of the process.
6249 If you bring up GDB on another SVR4 system, please send mail to
6250 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6252 * Better dynamic linking support in SunOS
6254 Reading symbols from shared libraries which contain debugging symbols
6255 now works properly. However, there remain issues such as automatic
6256 skipping of `transfer vector' code during function calls, which
6257 make it harder to debug code in a shared library, than to debug the
6258 same code linked statically.
6262 GDB is now using the latest `getopt' routines from the FSF. This
6263 version accepts the -- prefix for options with long names. GDB will
6264 continue to accept the old forms (-option and +option) as well.
6265 Various single letter abbreviations for options have been explicity
6266 added to the option table so that they won't get overshadowed in the
6267 future by other options that begin with the same letter.
6271 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6272 Many assorted bugs have been handled. Many more remain to be handled.
6273 See the various ChangeLog files (primarily in gdb and bfd) for details.
6276 *** Changes in GDB-4.3:
6278 * New machines supported (host and target)
6280 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6281 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6282 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6284 * Almost SCO Unix support
6286 We had hoped to support:
6287 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6288 (except for core file support), but we discovered very late in the release
6289 that it has problems with process groups that render gdb unusable. Sorry
6290 about that. I encourage people to fix it and post the fixes.
6292 * Preliminary ELF and DWARF support
6294 GDB can read ELF object files on System V Release 4, and can handle
6295 debugging records for C, in DWARF format, in ELF files. This support
6296 is preliminary. If you bring up GDB on another SVR4 system, please
6297 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6302 GDB now uses the latest `readline' library. One user-visible change
6303 is that two tabs will list possible command completions, which previously
6304 required typing M-? (meta-question mark, or ESC ?).
6308 The `stepi' bug that many of you noticed has been squashed.
6309 Many bugs in C++ have been handled. Many more remain to be handled.
6310 See the various ChangeLog files (primarily in gdb and bfd) for details.
6312 * State of the MIPS world (in case you wondered):
6314 GDB can understand the symbol tables emitted by the compilers
6315 supplied by most vendors of MIPS-based machines, including DEC. These
6316 symbol tables are in a format that essentially nobody else uses.
6318 Some versions of gcc come with an assembler post-processor called
6319 mips-tfile. This program is required if you want to do source-level
6320 debugging of gcc-compiled programs. I believe FSF does not ship
6321 mips-tfile with gcc version 1, but it will eventually come with gcc
6324 Debugging of g++ output remains a problem. g++ version 1.xx does not
6325 really support it at all. (If you're lucky, you should be able to get
6326 line numbers and stack traces to work, but no parameters or local
6327 variables.) With some work it should be possible to improve the
6330 When gcc version 2 is released, you will have somewhat better luck.
6331 However, even then you will get confusing results for inheritance and
6334 We will eventually provide full debugging of g++ output on
6335 DECstations. This will probably involve some kind of stabs-in-ecoff
6336 encapulation, but the details have not been worked out yet.
6339 *** Changes in GDB-4.2:
6341 * Improved configuration
6343 Only one copy of `configure' exists now, and it is not self-modifying.
6344 Porting BFD is simpler.
6348 The `step' and `next' commands now only stop at the first instruction
6349 of a source line. This prevents the multiple stops that used to occur
6350 in switch statements, for-loops, etc. `Step' continues to stop if a
6351 function that has debugging information is called within the line.
6355 Lots of small bugs fixed. More remain.
6357 * New host supported (not target)
6359 Intel 386 PC clone running Mach i386-none-mach
6362 *** Changes in GDB-4.1:
6364 * Multiple source language support
6366 GDB now has internal scaffolding to handle several source languages.
6367 It determines the type of each source file from its filename extension,
6368 and will switch expression parsing and number formatting to match the
6369 language of the function in the currently selected stack frame.
6370 You can also specifically set the language to be used, with
6371 `set language c' or `set language modula-2'.
6375 GDB now has preliminary support for the GNU Modula-2 compiler,
6376 currently under development at the State University of New York at
6377 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6378 continue through the fall of 1991 and into 1992.
6380 Other Modula-2 compilers are currently not supported, and attempting to
6381 debug programs compiled with them will likely result in an error as the
6382 symbol table is read. Feel free to work on it, though!
6384 There are hooks in GDB for strict type checking and range checking,
6385 in the `Modula-2 philosophy', but they do not currently work.
6389 GDB can now write to executable and core files (e.g. patch
6390 a variable's value). You must turn this switch on, specify
6391 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6392 by assigning a new value to a variable. Modifications take
6395 * Automatic SunOS shared library reading
6397 When you run your program, GDB automatically determines where its
6398 shared libraries (if any) have been loaded, and reads their symbols.
6399 The `share' command is no longer needed. This also works when
6400 examining core files.
6404 You can specify the number of lines that the `list' command shows.
6407 * New machines supported (host and target)
6409 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6410 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6411 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6413 * New hosts supported (not targets)
6415 IBM RT/PC: romp-ibm-aix or rtpc
6417 * New targets supported (not hosts)
6419 AMD 29000 embedded with COFF a29k-none-coff
6420 AMD 29000 embedded with a.out a29k-none-aout
6421 Ultracomputer remote kernel debug a29k-nyu-kern
6423 * New remote interfaces
6429 *** Changes in GDB-4.0:
6433 Wide output is wrapped at good places to make the output more readable.
6435 Gdb now supports cross-debugging from a host machine of one type to a
6436 target machine of another type. Communication with the target system
6437 is over serial lines. The ``target'' command handles connecting to the
6438 remote system; the ``load'' command will download a program into the
6439 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6440 also supports debugging of realtime processes running under VxWorks,
6441 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6442 stub on the target system.
6444 New CPUs supported include the AMD 29000 and Intel 960.
6446 GDB now reads object files and symbol tables via a ``binary file''
6447 library, which allows a single copy of GDB to debug programs of multiple
6448 object file types such as a.out and coff.
6450 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6451 refcard.dvi and refcard.ps are available to format it).
6454 * Control-Variable user interface simplified
6456 All variables that control the operation of the debugger can be set
6457 by the ``set'' command, and displayed by the ``show'' command.
6459 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6460 ``Show prompt'' produces the response:
6461 Gdb's prompt is new-gdb=>.
6463 What follows are the NEW set commands. The command ``help set'' will
6464 print a complete list of old and new set commands. ``help set FOO''
6465 will give a longer description of the variable FOO. ``show'' will show
6466 all of the variable descriptions and their current settings.
6468 confirm on/off: Enables warning questions for operations that are
6469 hard to recover from, e.g. rerunning the program while
6470 it is already running. Default is ON.
6472 editing on/off: Enables EMACS style command line editing
6473 of input. Previous lines can be recalled with
6474 control-P, the current line can be edited with control-B,
6475 you can search for commands with control-R, etc.
6478 history filename NAME: NAME is where the gdb command history
6479 will be stored. The default is .gdb_history,
6480 or the value of the environment variable
6483 history size N: The size, in commands, of the command history. The
6484 default is 256, or the value of the environment variable
6487 history save on/off: If this value is set to ON, the history file will
6488 be saved after exiting gdb. If set to OFF, the
6489 file will not be saved. The default is OFF.
6491 history expansion on/off: If this value is set to ON, then csh-like
6492 history expansion will be performed on
6493 command line input. The default is OFF.
6495 radix N: Sets the default radix for input and output. It can be set
6496 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6497 in the current radix, so "set radix 10" is always a no-op.
6499 height N: This integer value is the number of lines on a page. Default
6500 is 24, the current `stty rows'' setting, or the ``li#''
6501 setting from the termcap entry matching the environment
6504 width N: This integer value is the number of characters on a line.
6505 Default is 80, the current `stty cols'' setting, or the ``co#''
6506 setting from the termcap entry matching the environment
6509 Note: ``set screensize'' is obsolete. Use ``set height'' and
6510 ``set width'' instead.
6512 print address on/off: Print memory addresses in various command displays,
6513 such as stack traces and structure values. Gdb looks
6514 more ``symbolic'' if you turn this off; it looks more
6515 ``machine level'' with it on. Default is ON.
6517 print array on/off: Prettyprint arrays. New convenient format! Default
6520 print demangle on/off: Print C++ symbols in "source" form if on,
6523 print asm-demangle on/off: Same, for assembler level printouts
6526 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6529 * Support for Epoch Environment.
6531 The epoch environment is a version of Emacs v18 with windowing. One
6532 new command, ``inspect'', is identical to ``print'', except that if you
6533 are running in the epoch environment, the value is printed in its own
6537 * Support for Shared Libraries
6539 GDB can now debug programs and core files that use SunOS shared libraries.
6540 Symbols from a shared library cannot be referenced
6541 before the shared library has been linked with the program (this
6542 happens after you type ``run'' and before the function main() is entered).
6543 At any time after this linking (including when examining core files
6544 from dynamically linked programs), gdb reads the symbols from each
6545 shared library when you type the ``sharedlibrary'' command.
6546 It can be abbreviated ``share''.
6548 sharedlibrary REGEXP: Load shared object library symbols for files
6549 matching a unix regular expression. No argument
6550 indicates to load symbols for all shared libraries.
6552 info sharedlibrary: Status of loaded shared libraries.
6557 A watchpoint stops execution of a program whenever the value of an
6558 expression changes. Checking for this slows down execution
6559 tremendously whenever you are in the scope of the expression, but is
6560 quite useful for catching tough ``bit-spreader'' or pointer misuse
6561 problems. Some machines such as the 386 have hardware for doing this
6562 more quickly, and future versions of gdb will use this hardware.
6564 watch EXP: Set a watchpoint (breakpoint) for an expression.
6566 info watchpoints: Information about your watchpoints.
6568 delete N: Deletes watchpoint number N (same as breakpoints).
6569 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6570 enable N: Re-enables watchpoint number N (same as breakpoints).
6573 * C++ multiple inheritance
6575 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6578 * C++ exception handling
6580 Gdb now supports limited C++ exception handling. Besides the existing
6581 ability to breakpoint on an exception handler, gdb can breakpoint on
6582 the raising of an exception (before the stack is peeled back to the
6585 catch FOO: If there is a FOO exception handler in the dynamic scope,
6586 set a breakpoint to catch exceptions which may be raised there.
6587 Multiple exceptions (``catch foo bar baz'') may be caught.
6589 info catch: Lists all exceptions which may be caught in the
6590 current stack frame.
6593 * Minor command changes
6595 The command ``call func (arg, arg, ...)'' now acts like the print
6596 command, except it does not print or save a value if the function's result
6597 is void. This is similar to dbx usage.
6599 The ``up'' and ``down'' commands now always print the frame they end up
6600 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6601 frames without printing.
6603 * New directory command
6605 'dir' now adds directories to the FRONT of the source search path.
6606 The path starts off empty. Source files that contain debug information
6607 about the directory in which they were compiled can be found even
6608 with an empty path; Sun CC and GCC include this information. If GDB can't
6609 find your source file in the current directory, type "dir .".
6611 * Configuring GDB for compilation
6613 For normal use, type ``./configure host''. See README or gdb.texinfo
6616 GDB now handles cross debugging. If you are remotely debugging between
6617 two different machines, type ``./configure host -target=targ''.
6618 Host is the machine where GDB will run; targ is the machine
6619 where the program that you are debugging will run.
projects / external / binutils.git / blob