1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.0
6 * On Unix systems, GDB now supports transmitting environment variables
7 that are to be set or unset to GDBserver. These variables will
8 affect the environment to be passed to the remote inferior.
10 To inform GDB of environment variables that are to be transmitted to
11 GDBserver, use the "set environment" command. Only user set
12 environment variables are sent to GDBserver.
14 To inform GDB of environment variables that are to be unset before
15 the remote inferior is started by the GDBserver, use the "unset
18 * New features in the GDB remote stub, GDBserver
20 ** New "--selftest" command line option runs some GDBserver self
21 tests. These self tests are disabled in releases.
23 ** On Unix systems, GDBserver now does globbing expansion and variable
24 substitution in inferior command line arguments.
26 This is done by starting inferiors using a shell, like GDB does.
27 See "set startup-with-shell" in the user manual for how to disable
28 this from GDB when using "target extended-remote". When using
29 "target remote", you can disable the startup with shell by using the
30 new "--no-startup-with-shell" GDBserver command line option.
32 ** On Unix systems, GDBserver now supports receiving environment
33 variables that are to be set or unset from GDB. These variables
34 will affect the environment to be passed to the inferior.
38 QEnvironmentHexEncoded
39 Inform GDBserver of an environment variable that is to be passed to
40 the inferior when starting it.
43 Inform GDBserver of an environment variable that is to be unset
44 before starting the remote inferior.
47 Inform GDBserver that the environment should be reset (i.e.,
48 user-set environment variables should be unset).
51 Indicates whether the inferior must be started with a shell or not.
53 * The "maintenance print c-tdesc" command now takes an optional
54 argument which is the file name of XML target description.
59 Set and show compilation command used for compiling and injecting code
60 with the 'compile' commands.
62 set debug separate-debug-file
63 show debug separate-debug-file
64 Control the display of debug output about separate debug file search.
66 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
69 *** Changes in GDB 8.0
71 * GDB now supports access to the PKU register on GNU/Linux. The register is
72 added by the Memory Protection Keys for Userspace feature which will be
73 available in future Intel CPUs.
75 * GDB now supports C++11 rvalue references.
79 ** New functions to start, stop and access a running btrace recording.
80 ** Rvalue references are now supported in gdb.Type.
82 * GDB now supports recording and replaying rdrand and rdseed Intel 64
85 * Building GDB and GDBserver now requires a C++11 compiler.
87 For example, GCC 4.8 or later.
89 It is no longer possible to build GDB or GDBserver with a C
90 compiler. The --disable-build-with-cxx configure option has been
93 * Building GDB and GDBserver now requires GNU make >= 3.81.
95 It is no longer supported to build GDB or GDBserver with another
96 implementation of the make program or an earlier version of GNU make.
98 * Native debugging on MS-Windows supports command-line redirection
100 Command-line arguments used for starting programs on MS-Windows can
101 now include redirection symbols supported by native Windows shells,
102 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
103 as "run", "start", and "set args", as well as the corresponding MI
106 * Support for thread names on MS-Windows.
108 GDB now catches and handles the special exception that programs
109 running on MS-Windows use to assign names to threads in the
112 * Support for Java programs compiled with gcj has been removed.
114 * User commands now accept an unlimited number of arguments.
115 Previously, only up to 10 was accepted.
117 * The "eval" command now expands user-defined command arguments.
119 This makes it easier to process a variable number of arguments:
124 eval "print $arg%d", $i
129 * Target descriptions can now describe registers for sparc32 and sparc64.
131 * GDB now supports DWARF version 5 (debug information format).
132 Its .debug_names index is not yet supported.
134 * New native configurations
136 FreeBSD/mips mips*-*-freebsd
140 Synopsys ARC arc*-*-elf32
141 FreeBSD/mips mips*-*-freebsd
143 * Removed targets and native configurations
145 Alpha running FreeBSD alpha*-*-freebsd*
146 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
151 Erases all the flash memory regions reported by the target.
153 maint print arc arc-instruction address
154 Print internal disassembler information about instruction at a given address.
158 set disassembler-options
159 show disassembler-options
160 Controls the passing of target specific information to the disassembler.
161 If it is necessary to specify more than one disassembler option then
162 multiple options can be placed together into a comma separated list.
163 The default value is the empty string. Currently, the only supported
164 targets are ARM, PowerPC and S/390.
169 Erases all the flash memory regions reported by the target. This is
170 equivalent to the CLI command flash-erase.
172 -file-list-shared-libraries
173 List the shared libraries in the program. This is
174 equivalent to the CLI command "info shared".
176 *** Changes in GDB 7.12
178 * GDB and GDBserver now build with a C++ compiler by default.
180 The --enable-build-with-cxx configure option is now enabled by
181 default. One must now explicitly configure with
182 --disable-build-with-cxx in order to build with a C compiler. This
183 option will be removed in a future release.
185 * GDBserver now supports recording btrace without maintaining an active
188 * GDB now supports a negative repeat count in the 'x' command to examine
189 memory backward from the given address. For example:
192 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
193 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
194 (gdb) x/-5i 0x0000000000400580
195 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
196 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
197 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
198 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
199 0x40057b <main(int, char**)+25>:
200 callq 0x400536 <Func1(int, char const*)>
202 * Fortran: Support structures with fields of dynamic types and
203 arrays of dynamic types.
205 * The symbol dumping maintenance commands have new syntax.
206 maint print symbols [-pc address] [--] [filename]
207 maint print symbols [-objfile objfile] [-source source] [--] [filename]
208 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
209 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
210 maint print msymbols [-objfile objfile] [--] [filename]
212 * GDB now supports multibit bitfields and enums in target register
215 * New Python-based convenience function $_as_string(val), which returns
216 the textual representation of a value. This function is especially
217 useful to obtain the text label of an enum value.
219 * Intel MPX bound violation handling.
221 Segmentation faults caused by a Intel MPX boundary violation
222 now display the kind of violation (upper or lower), the memory
223 address accessed and the memory bounds, along with the usual
224 signal received and code location.
228 Program received signal SIGSEGV, Segmentation fault
229 Upper bound violation while accessing address 0x7fffffffc3b3
230 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
231 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
233 * Rust language support.
234 GDB now supports debugging programs written in the Rust programming
235 language. See https://www.rust-lang.org/ for more information about
238 * Support for running interpreters on specified input/output devices
240 GDB now supports a new mechanism that allows frontends to provide
241 fully featured GDB console views, as a better alternative to
242 building such views on top of the "-interpreter-exec console"
243 command. See the new "new-ui" command below. With that command,
244 frontends can now start GDB in the traditional command-line mode
245 running in an embedded terminal emulator widget, and create a
246 separate MI interpreter running on a specified i/o device. In this
247 way, GDB handles line editing, history, tab completion, etc. in the
248 console all by itself, and the GUI uses the separate MI interpreter
249 for its own control and synchronization, invisible to the command
252 * The "catch syscall" command catches groups of related syscalls.
254 The "catch syscall" command now supports catching a group of related
255 syscalls using the 'group:' or 'g:' prefix.
260 skip -gfile file-glob-pattern
261 skip -function function
262 skip -rfunction regular-expression
263 A generalized form of the skip command, with new support for
264 glob-style file names and regular expressions for function names.
265 Additionally, a file spec and a function spec may now be combined.
267 maint info line-table REGEXP
268 Display the contents of GDB's internal line table data struture.
271 Run any GDB unit tests that were compiled in.
274 Start a new user interface instance running INTERP as interpreter,
275 using the TTY file for input/output.
279 ** gdb.Breakpoint objects have a new attribute "pending", which
280 indicates whether the breakpoint is pending.
281 ** Three new breakpoint-related events have been added:
282 gdb.breakpoint_created, gdb.breakpoint_modified, and
283 gdb.breakpoint_deleted.
286 Signal ("set") the given MS-Windows event object. This is used in
287 conjunction with the Windows JIT debugging (AeDebug) support, where
288 the OS suspends a crashing process until a debugger can attach to
289 it. Resuming the crashing process, in order to debug it, is done by
292 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
293 was added in GDBserver, including JIT compiling fast tracepoint's
294 conditional expression bytecode into native code.
296 * Support for various remote target protocols and ROM monitors has
299 target m32rsdi Remote M32R debugging over SDI
300 target mips MIPS remote debugging protocol
301 target pmon PMON ROM monitor
302 target ddb NEC's DDB variant of PMON for Vr4300
303 target rockhopper NEC RockHopper variant of PMON
304 target lsi LSI variant of PMO
306 * Support for tracepoints and fast tracepoints on powerpc-linux,
307 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
308 including JIT compiling fast tracepoint's conditional expression
309 bytecode into native code.
311 * MI async record =record-started now includes the method and format used for
312 recording. For example:
314 =record-started,thread-group="i1",method="btrace",format="bts"
316 * MI async record =thread-selected now includes the frame field. For example:
318 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
322 Andes NDS32 nds32*-*-elf
324 *** Changes in GDB 7.11
326 * GDB now supports debugging kernel-based threads on FreeBSD.
328 * Per-inferior thread numbers
330 Thread numbers are now per inferior instead of global. If you're
331 debugging multiple inferiors, GDB displays thread IDs using a
332 qualified INF_NUM.THR_NUM form. For example:
336 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
337 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
338 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
339 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
341 As consequence, thread numbers as visible in the $_thread
342 convenience variable and in Python's InferiorThread.num attribute
343 are no longer unique between inferiors.
345 GDB now maintains a second thread ID per thread, referred to as the
346 global thread ID, which is the new equivalent of thread numbers in
347 previous releases. See also $_gthread below.
349 For backwards compatibility, MI's thread IDs always refer to global
352 * Commands that accept thread IDs now accept the qualified
353 INF_NUM.THR_NUM form as well. For example:
356 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
359 * In commands that accept a list of thread IDs, you can now refer to
360 all threads of an inferior using a star wildcard. GDB accepts
361 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
362 refer to all threads of the current inferior. For example, "info
365 * You can use "info threads -gid" to display the global thread ID of
368 * The new convenience variable $_gthread holds the global number of
371 * The new convenience variable $_inferior holds the number of the
374 * GDB now displays the ID and name of the thread that hit a breakpoint
375 or received a signal, if your program is multi-threaded. For
378 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
379 Thread 1 "main" received signal SIGINT, Interrupt.
381 * Record btrace now supports non-stop mode.
383 * Support for tracepoints on aarch64-linux was added in GDBserver.
385 * The 'record instruction-history' command now indicates speculative execution
386 when using the Intel Processor Trace recording format.
388 * GDB now allows users to specify explicit locations, bypassing
389 the linespec parser. This feature is also available to GDB/MI
392 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
393 GDB now is able to debug both AArch64 applications and ARM applications
396 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
397 including JIT compiling fast tracepoint's conditional expression bytecode
400 * GDB now supports displaced stepping on AArch64 GNU/Linux.
402 * "info threads", "info inferiors", "info display", "info checkpoints"
403 and "maint info program-spaces" now list the corresponding items in
404 ascending ID order, for consistency with all other "info" commands.
406 * In Ada, the overloads selection menu has been enhanced to display the
407 parameter types and the return types for the matching overloaded subprograms.
411 maint set target-non-stop (on|off|auto)
412 maint show target-non-stop
413 Control whether GDB targets always operate in non-stop mode even if
414 "set non-stop" is "off". The default is "auto", meaning non-stop
415 mode is enabled if supported by the target.
417 maint set bfd-sharing
418 maint show bfd-sharing
419 Control the reuse of bfd objects.
423 Control display of debugging info regarding bfd caching.
427 Control display of debugging info regarding FreeBSD threads.
429 set remote multiprocess-extensions-packet
430 show remote multiprocess-extensions-packet
431 Set/show the use of the remote protocol multiprocess extensions.
433 set remote thread-events
434 show remote thread-events
435 Set/show the use of thread create/exit events.
437 set ada print-signatures on|off
438 show ada print-signatures"
439 Control whether parameter types and return types are displayed in overloads
440 selection menus. It is activaled (@code{on}) by default.
444 Controls the maximum size of memory, in bytes, that GDB will
445 allocate for value contents. Prevents incorrect programs from
446 causing GDB to allocate overly large buffers. Default is 64k.
448 * The "disassemble" command accepts a new modifier: /s.
449 It prints mixed source+disassembly like /m with two differences:
450 - disassembled instructions are now printed in program order, and
451 - and source for all relevant files is now printed.
452 The "/m" option is now considered deprecated: its "source-centric"
453 output hasn't proved useful in practice.
455 * The "record instruction-history" command accepts a new modifier: /s.
456 It behaves exactly like /m and prints mixed source+disassembly.
458 * The "set scheduler-locking" command supports a new mode "replay".
459 It behaves like "off" in record mode and like "on" in replay mode.
461 * Support for various ROM monitors has been removed:
463 target dbug dBUG ROM monitor for Motorola ColdFire
464 target picobug Motorola picobug monitor
465 target dink32 DINK32 ROM monitor for PowerPC
466 target m32r Renesas M32R/D ROM monitor
467 target mon2000 mon2000 ROM monitor
468 target ppcbug PPCBUG ROM monitor for PowerPC
470 * Support for reading/writing memory and extracting values on architectures
471 whose memory is addressable in units of any integral multiple of 8 bits.
476 Indicates whether the inferior must be started with a shell or not.
479 Indicates that an exec system call was executed.
481 exec-events feature in qSupported
482 The qSupported packet allows GDB to request support for exec
483 events using the new 'gdbfeature' exec-event, and the qSupported
484 response can contain the corresponding 'stubfeature'. Set and
485 show commands can be used to display whether these features are enabled.
488 Equivalent to interrupting with the ^C character, but works in
491 thread created stop reason (T05 create:...)
492 Indicates that the thread was just created and is stopped at entry.
494 thread exit stop reply (w exitcode;tid)
495 Indicates that the thread has terminated.
498 Enables/disables thread create and exit event reporting. For
499 example, this is used in non-stop mode when GDB stops a set of
500 threads and synchronously waits for the their corresponding stop
501 replies. Without exit events, if one of the threads exits, GDB
502 would hang forever not knowing that it should no longer expect a
503 stop for that same thread.
506 Indicates that there are no resumed threads left in the target (all
507 threads are stopped). The remote stub reports support for this stop
508 reply to GDB's qSupported query.
511 Enables/disables catching syscalls from the inferior process.
512 The remote stub reports support for this packet to GDB's qSupported query.
514 syscall_entry stop reason
515 Indicates that a syscall was just called.
517 syscall_return stop reason
518 Indicates that a syscall just returned.
520 * Extended-remote exec events
522 ** GDB now has support for exec events on extended-remote Linux targets.
523 For such targets with Linux kernels 2.5.46 and later, this enables
524 follow-exec-mode and exec catchpoints.
526 set remote exec-event-feature-packet
527 show remote exec-event-feature-packet
528 Set/show the use of the remote exec event feature.
530 * Thread names in remote protocol
532 The reply to qXfer:threads:read may now include a name attribute for each
535 * Target remote mode fork and exec events
537 ** GDB now has support for fork and exec events on target remote mode
538 Linux targets. For such targets with Linux kernels 2.5.46 and later,
539 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
540 fork and exec catchpoints.
542 * Remote syscall events
544 ** GDB now has support for catch syscall on remote Linux targets,
545 currently enabled on x86/x86_64 architectures.
547 set remote catch-syscall-packet
548 show remote catch-syscall-packet
549 Set/show the use of the remote catch syscall feature.
553 ** The -var-set-format command now accepts the zero-hexadecimal
554 format. It outputs data in hexadecimal format with zero-padding on the
559 ** gdb.InferiorThread objects have a new attribute "global_num",
560 which refers to the thread's global thread ID. The existing
561 "num" attribute now refers to the thread's per-inferior number.
562 See "Per-inferior thread numbers" above.
563 ** gdb.InferiorThread objects have a new attribute "inferior", which
564 is the Inferior object the thread belongs to.
566 *** Changes in GDB 7.10
568 * Support for process record-replay and reverse debugging on aarch64*-linux*
569 targets has been added. GDB now supports recording of A64 instruction set
570 including advance SIMD instructions.
572 * Support for Sun's version of the "stabs" debug file format has been removed.
574 * GDB now honors the content of the file /proc/PID/coredump_filter
575 (PID is the process ID) on GNU/Linux systems. This file can be used
576 to specify the types of memory mappings that will be included in a
577 corefile. For more information, please refer to the manual page of
578 "core(5)". GDB also has a new command: "set use-coredump-filter
579 on|off". It allows to set whether GDB will read the content of the
580 /proc/PID/coredump_filter file when generating a corefile.
582 * The "info os" command on GNU/Linux can now display information on
584 "info os cpus" Listing of all cpus/cores on the system
586 * GDB has two new commands: "set serial parity odd|even|none" and
587 "show serial parity". These allows to set or show parity for the
590 * The "info source" command now displays the producer string if it was
591 present in the debug info. This typically includes the compiler version
592 and may include things like its command line arguments.
594 * The "info dll", an alias of the "info sharedlibrary" command,
595 is now available on all platforms.
597 * Directory names supplied to the "set sysroot" commands may be
598 prefixed with "target:" to tell GDB to access shared libraries from
599 the target system, be it local or remote. This replaces the prefix
600 "remote:". The default sysroot has been changed from "" to
601 "target:". "remote:" is automatically converted to "target:" for
602 backward compatibility.
604 * The system root specified by "set sysroot" will be prepended to the
605 filename of the main executable (if reported to GDB as absolute by
606 the operating system) when starting processes remotely, and when
607 attaching to already-running local or remote processes.
609 * GDB now supports automatic location and retrieval of executable
610 files from remote targets. Remote debugging can now be initiated
611 using only a "target remote" or "target extended-remote" command
612 (no "set sysroot" or "file" commands are required). See "New remote
615 * The "dump" command now supports verilog hex format.
617 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
619 * On GNU/Linux, GDB and gdbserver are now able to access executable
620 and shared library files without a "set sysroot" command when
621 attaching to processes running in different mount namespaces from
622 the debugger. This makes it possible to attach to processes in
623 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
624 See "New remote packets" below.
626 * The "tui reg" command now provides completion for all of the
627 available register groups, including target specific groups.
629 * The HISTSIZE environment variable is no longer read when determining
630 the size of GDB's command history. GDB now instead reads the dedicated
631 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
632 disables truncation of command history. Non-numeric values of GDBHISTSIZE
637 ** Memory ports can now be unbuffered.
641 ** gdb.Objfile objects have a new attribute "username",
642 which is the name of the objfile as specified by the user,
643 without, for example, resolving symlinks.
644 ** You can now write frame unwinders in Python.
645 ** gdb.Type objects have a new method "optimized_out",
646 returning optimized out gdb.Value instance of this type.
647 ** gdb.Value objects have new methods "reference_value" and
648 "const_value" which return a reference to the value and a
649 "const" version of the value respectively.
653 maint print symbol-cache
654 Print the contents of the symbol cache.
656 maint print symbol-cache-statistics
657 Print statistics of symbol cache usage.
659 maint flush-symbol-cache
660 Flush the contents of the symbol cache.
664 Start branch trace recording using Branch Trace Store (BTS) format.
667 Evaluate expression by using the compiler and print result.
671 Explicit commands for enabling and disabling tui mode.
674 set mpx bound on i386 and amd64
675 Support for bound table investigation on Intel MPX enabled applications.
679 Start branch trace recording using Intel Processor Trace format.
682 Print information about branch tracing internals.
684 maint btrace packet-history
685 Print the raw branch tracing data.
687 maint btrace clear-packet-history
688 Discard the stored raw branch tracing data.
691 Discard all branch tracing data. It will be fetched and processed
692 anew by the next "record" command.
697 Renamed from "set debug dwarf2-die".
699 Renamed from "show debug dwarf2-die".
702 Renamed from "set debug dwarf2-read".
703 show debug dwarf-read
704 Renamed from "show debug dwarf2-read".
706 maint set dwarf always-disassemble
707 Renamed from "maint set dwarf2 always-disassemble".
708 maint show dwarf always-disassemble
709 Renamed from "maint show dwarf2 always-disassemble".
711 maint set dwarf max-cache-age
712 Renamed from "maint set dwarf2 max-cache-age".
713 maint show dwarf max-cache-age
714 Renamed from "maint show dwarf2 max-cache-age".
717 show debug dwarf-line
718 Control display of debugging info regarding DWARF line processing.
722 Set the maximum number of candidates to be considered during
723 completion. The default value is 200. This limit allows GDB
724 to avoid generating large completion lists, the computation of
725 which can cause the debugger to become temporarily unresponsive.
727 set history remove-duplicates
728 show history remove-duplicates
729 Control the removal of duplicate history entries.
731 maint set symbol-cache-size
732 maint show symbol-cache-size
733 Control the size of the symbol cache.
735 set|show record btrace bts buffer-size
736 Set and show the size of the ring buffer used for branch tracing in
738 The obtained size may differ from the requested size. Use "info
739 record" to see the obtained buffer size.
741 set debug linux-namespaces
742 show debug linux-namespaces
743 Control display of debugging info regarding Linux namespaces.
745 set|show record btrace pt buffer-size
746 Set and show the size of the ring buffer used for branch tracing in
747 Intel Processor Trace format.
748 The obtained size may differ from the requested size. Use "info
749 record" to see the obtained buffer size.
751 maint set|show btrace pt skip-pad
752 Set and show whether PAD packets are skipped when computing the
755 * The command 'thread apply all' can now support new option '-ascending'
756 to call its specified command for all threads in ascending order.
758 * Python/Guile scripting
760 ** GDB now supports auto-loading of Python/Guile scripts contained in the
761 special section named `.debug_gdb_scripts'.
765 qXfer:btrace-conf:read
766 Return the branch trace configuration for the current thread.
768 Qbtrace-conf:bts:size
769 Set the requested ring buffer size for branch tracing in BTS format.
772 Enable Intel Procesor Trace-based branch tracing for the current
773 process. The remote stub reports support for this packet to GDB's
777 Set the requested ring buffer size for branch tracing in Intel Processor
781 Indicates a memory breakpoint instruction was executed, irrespective
782 of whether it was GDB that planted the breakpoint or the breakpoint
783 is hardcoded in the program. This is required for correct non-stop
787 Indicates the target stopped for a hardware breakpoint. This is
788 required for correct non-stop mode operation.
791 Return information about files on the remote system.
794 Return the full absolute name of the file that was executed to
795 create a process running on the remote system.
798 Select the filesystem on which vFile: operations with filename
799 arguments will operate. This is required for GDB to be able to
800 access files on remote targets where the remote stub does not
801 share a common filesystem with the inferior(s).
804 Indicates that a fork system call was executed.
807 Indicates that a vfork system call was executed.
809 vforkdone stop reason
810 Indicates that a vfork child of the specified process has executed
811 an exec or exit, allowing the vfork parent to resume execution.
813 fork-events and vfork-events features in qSupported
814 The qSupported packet allows GDB to request support for fork and
815 vfork events using new 'gdbfeatures' fork-events and vfork-events,
816 and the qSupported response can contain the corresponding
817 'stubfeatures'. Set and show commands can be used to display
818 whether these features are enabled.
820 * Extended-remote fork events
822 ** GDB now has support for fork events on extended-remote Linux
823 targets. For targets with Linux kernels 2.5.60 and later, this
824 enables follow-fork-mode and detach-on-fork for both fork and
825 vfork, as well as fork and vfork catchpoints.
827 * The info record command now shows the recording format and the
828 branch tracing configuration for the current thread when using
829 the btrace record target.
830 For the BTS format, it shows the ring buffer size.
832 * GDB now has support for DTrace USDT (Userland Static Defined
833 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
835 * GDB now supports access to vector registers on S/390 GNU/Linux
838 * Removed command line options
840 -xdb HP-UX XDB compatibility mode.
842 * Removed targets and native configurations
844 HP/PA running HP-UX hppa*-*-hpux*
845 Itanium running HP-UX ia64-*-hpux*
847 * New configure options
850 This configure option allows the user to build GDB with support for
851 Intel Processor Trace (default: auto). This requires libipt.
853 --with-libipt-prefix=PATH
854 Specify the path to the version of libipt that GDB should use.
855 $PATH/include should contain the intel-pt.h header and
856 $PATH/lib should contain the libipt.so library.
858 *** Changes in GDB 7.9.1
862 ** Xmethods can now specify a result type.
864 *** Changes in GDB 7.9
866 * GDB now supports hardware watchpoints on x86 GNU Hurd.
870 ** You can now access frame registers from Python scripts.
871 ** New attribute 'producer' for gdb.Symtab objects.
872 ** gdb.Objfile objects have a new attribute "progspace",
873 which is the gdb.Progspace object of the containing program space.
874 ** gdb.Objfile objects have a new attribute "owner".
875 ** gdb.Objfile objects have a new attribute "build_id",
876 which is the build ID generated when the file was built.
877 ** gdb.Objfile objects have a new method "add_separate_debug_file".
878 ** A new event "gdb.clear_objfiles" has been added, triggered when
879 selecting a new file to debug.
880 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
881 ** New function gdb.lookup_objfile.
883 New events which are triggered when GDB modifies the state of the
886 ** gdb.events.inferior_call_pre: Function call is about to be made.
887 ** gdb.events.inferior_call_post: Function call has just been made.
888 ** gdb.events.memory_changed: A memory location has been altered.
889 ** gdb.events.register_changed: A register has been altered.
891 * New Python-based convenience functions:
893 ** $_caller_is(name [, number_of_frames])
894 ** $_caller_matches(regexp [, number_of_frames])
895 ** $_any_caller_is(name [, number_of_frames])
896 ** $_any_caller_matches(regexp [, number_of_frames])
898 * GDB now supports the compilation and injection of source code into
899 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
900 to compile the source code to object code, and if successful, inject
901 and execute that code within the current context of the inferior.
902 Currently the C language is supported. The commands used to
903 interface with this new feature are:
905 compile code [-raw|-r] [--] [source code]
906 compile file [-raw|-r] filename
910 demangle [-l language] [--] name
911 Demangle "name" in the specified language, or the current language
912 if elided. This command is renamed from the "maint demangle" command.
913 The latter is kept as a no-op to avoid "maint demangle" being interpreted
914 as "maint demangler-warning".
916 queue-signal signal-name-or-number
917 Queue a signal to be delivered to the thread when it is resumed.
919 add-auto-load-scripts-directory directory
920 Add entries to the list of directories from which to load auto-loaded
923 maint print user-registers
924 List all currently available "user" registers.
926 compile code [-r|-raw] [--] [source code]
927 Compile, inject, and execute in the inferior the executable object
928 code produced by compiling the provided source code.
930 compile file [-r|-raw] filename
931 Compile and inject into the inferior the executable object code
932 produced by compiling the source code stored in the filename
935 * On resume, GDB now always passes the signal the program had stopped
936 for to the thread the signal was sent to, even if the user changed
937 threads before resuming. Previously GDB would often (but not
938 always) deliver the signal to the thread that happens to be current
941 * Conversely, the "signal" command now consistently delivers the
942 requested signal to the current thread. GDB now asks for
943 confirmation if the program had stopped for a signal and the user
944 switched threads meanwhile.
946 * "breakpoint always-inserted" modes "off" and "auto" merged.
948 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
949 won't remove breakpoints from the target until all threads stop,
950 even in non-stop mode. The "auto" mode has been removed, and "off"
951 is now the default mode.
955 set debug symbol-lookup
956 show debug symbol-lookup
957 Control display of debugging info regarding symbol lookup.
961 ** The -list-thread-groups command outputs an exit-code field for
962 inferiors that have exited.
966 MIPS SDE mips*-sde*-elf*
970 Support for these obsolete configurations has been removed.
972 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
973 SGI Irix-5.x mips-*-irix5*
974 SGI Irix-6.x mips-*-irix6*
975 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
976 VAX running Ultrix vax-*-ultrix*
978 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
979 and "assf"), have been removed. Use the "sharedlibrary" command, or
980 its alias "share", instead.
982 *** Changes in GDB 7.8
984 * New command line options
987 This is an alias for the --data-directory option.
989 * GDB supports printing and modifying of variable length automatic arrays
990 as specified in ISO C99.
992 * The ARM simulator now supports instruction level tracing
993 with or without disassembly.
997 GDB now has support for scripting using Guile. Whether this is
998 available is determined at configure time.
999 Guile version 2.0 or greater is required.
1000 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1002 * New commands (for set/show, see "New options" below)
1006 Invoke CODE by passing it to the Guile interpreter.
1010 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1012 info auto-load guile-scripts [regexp]
1013 Print the list of automatically loaded Guile scripts.
1015 * The source command is now capable of sourcing Guile scripts.
1016 This feature is dependent on the debugger being built with Guile support.
1020 set print symbol-loading (off|brief|full)
1021 show print symbol-loading
1022 Control whether to print informational messages when loading symbol
1023 information for a file. The default is "full", but when debugging
1024 programs with large numbers of shared libraries the amount of output
1025 becomes less useful.
1027 set guile print-stack (none|message|full)
1028 show guile print-stack
1029 Show a stack trace when an error is encountered in a Guile script.
1031 set auto-load guile-scripts (on|off)
1032 show auto-load guile-scripts
1033 Control auto-loading of Guile script files.
1035 maint ada set ignore-descriptive-types (on|off)
1036 maint ada show ignore-descriptive-types
1037 Control whether the debugger should ignore descriptive types in Ada
1038 programs. The default is not to ignore the descriptive types. See
1039 the user manual for more details on descriptive types and the intended
1040 usage of this option.
1042 set auto-connect-native-target
1044 Control whether GDB is allowed to automatically connect to the
1045 native target for the run, attach, etc. commands when not connected
1046 to any target yet. See also "target native" below.
1048 set record btrace replay-memory-access (read-only|read-write)
1049 show record btrace replay-memory-access
1050 Control what memory accesses are allowed during replay.
1052 maint set target-async (on|off)
1053 maint show target-async
1054 This controls whether GDB targets operate in synchronous or
1055 asynchronous mode. Normally the default is asynchronous, if it is
1056 available; but this can be changed to more easily debug problems
1057 occurring only in synchronous mode.
1059 set mi-async (on|off)
1061 Control whether MI asynchronous mode is preferred. This supersedes
1062 "set target-async" of previous GDB versions.
1064 * "set target-async" is deprecated as a CLI option and is now an alias
1065 for "set mi-async" (only puts MI into async mode).
1067 * Background execution commands (e.g., "c&", "s&", etc.) are now
1068 possible ``out of the box'' if the target supports them. Previously
1069 the user would need to explicitly enable the possibility with the
1070 "set target-async on" command.
1072 * New features in the GDB remote stub, GDBserver
1074 ** New option --debug-format=option1[,option2,...] allows one to add
1075 additional text to each output. At present only timestamps
1076 are supported: --debug-format=timestamps.
1077 Timestamps can also be turned on with the
1078 "monitor set debug-format timestamps" command from GDB.
1080 * The 'record instruction-history' command now starts counting instructions
1081 at one. This also affects the instruction ranges reported by the
1082 'record function-call-history' command when given the /i modifier.
1084 * The command 'record function-call-history' supports a new modifier '/c' to
1085 indent the function names based on their call stack depth.
1086 The fields for the '/i' and '/l' modifier have been reordered.
1087 The source line range is now prefixed with 'at'.
1088 The instruction range is now prefixed with 'inst'.
1089 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1090 "record instruction-history" and "list" commands.
1092 * The ranges given as arguments to the 'record function-call-history' and
1093 'record instruction-history' commands are now inclusive.
1095 * The btrace record target now supports the 'record goto' command.
1096 For locations inside the execution trace, the back trace is computed
1097 based on the information stored in the execution trace.
1099 * The btrace record target supports limited reverse execution and replay.
1100 The target does not record data and therefore does not allow reading
1101 memory or registers.
1103 * The "catch syscall" command now works on s390*-linux* targets.
1105 * The "compare-sections" command is no longer specific to target
1106 remote. It now works with all targets.
1108 * All native targets are now consistently called "native".
1109 Consequently, the "target child", "target GNU", "target djgpp",
1110 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1111 commands have been replaced with "target native". The QNX/NTO port
1112 leaves the "procfs" target in place and adds a "native" target for
1113 consistency with other ports. The impact on users should be minimal
1114 as these commands previously either throwed an error, or were
1115 no-ops. The target's name is visible in the output of the following
1116 commands: "help target", "info target", "info files", "maint print
1119 * The "target native" command now connects to the native target. This
1120 can be used to launch native programs even when "set
1121 auto-connect-native-target" is set to off.
1123 * GDB now supports access to Intel MPX registers on GNU/Linux.
1125 * Support for Intel AVX-512 registers on GNU/Linux.
1126 Support displaying and modifying Intel AVX-512 registers
1127 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1129 * New remote packets
1131 qXfer:btrace:read's annex
1132 The qXfer:btrace:read packet supports a new annex 'delta' to read
1133 branch trace incrementally.
1137 ** Valid Python operations on gdb.Value objects representing
1138 structs/classes invoke the corresponding overloaded operators if
1140 ** New `Xmethods' feature in the Python API. Xmethods are
1141 additional methods or replacements for existing methods of a C++
1142 class. This feature is useful for those cases where a method
1143 defined in C++ source code could be inlined or optimized out by
1144 the compiler, making it unavailable to GDB.
1147 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1149 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1150 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1151 its alias "share", instead.
1153 * The commands "set remotebaud" and "show remotebaud" are no longer
1154 supported. Use "set serial baud" and "show serial baud" (respectively)
1159 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1160 target-async". The latter is left as a deprecated alias of the
1161 former for backward compatibility. If the target supports it,
1162 CLI background execution commands are now always possible by
1163 default, independently of whether the frontend stated a
1164 preference for asynchronous execution with "-gdb-set mi-async".
1165 Previously "-gdb-set target-async off" affected both MI execution
1166 commands and CLI execution commands.
1168 *** Changes in GDB 7.7
1170 * Improved support for process record-replay and reverse debugging on
1171 arm*-linux* targets. Support for thumb32 and syscall instruction
1172 recording has been added.
1174 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1176 * GDB now supports Fission DWP file format version 2.
1177 http://gcc.gnu.org/wiki/DebugFission
1179 * New convenience function "$_isvoid", to check whether an expression
1180 is void. A void expression is an expression where the type of the
1181 result is "void". For example, some convenience variables may be
1182 "void" when evaluated (e.g., "$_exitcode" before the execution of
1183 the program being debugged; or an undefined convenience variable).
1184 Another example, when calling a function whose return type is
1187 * The "maintenance print objfiles" command now takes an optional regexp.
1189 * The "catch syscall" command now works on arm*-linux* targets.
1191 * GDB now consistently shows "<not saved>" when printing values of
1192 registers the debug info indicates have not been saved in the frame
1193 and there's nowhere to retrieve them from
1194 (callee-saved/call-clobbered registers):
1199 (gdb) info registers rax
1202 Before, the former would print "<optimized out>", and the latter
1203 "*value not available*".
1205 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1210 ** Frame filters and frame decorators have been added.
1211 ** Temporary breakpoints are now supported.
1212 ** Line tables representation has been added.
1213 ** New attribute 'parent_type' for gdb.Field objects.
1214 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1215 ** New attribute 'name' for gdb.Type objects.
1219 Nios II ELF nios2*-*-elf
1220 Nios II GNU/Linux nios2*-*-linux
1221 Texas Instruments MSP430 msp430*-*-elf
1223 * Removed native configurations
1225 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1226 been removed. ELF variants of these configurations are kept supported.
1228 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1229 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1230 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1231 i[34567]86-*-openbsd3.[0-3]
1232 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1233 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1234 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1238 Like "catch throw", but catches a re-thrown exception.
1239 maint check-psymtabs
1240 Renamed from old "maint check-symtabs".
1242 Perform consistency checks on symtabs.
1243 maint expand-symtabs
1244 Expand symtabs matching an optional regexp.
1247 Display the details of GDB configure-time options.
1249 maint set|show per-command
1250 maint set|show per-command space
1251 maint set|show per-command time
1252 maint set|show per-command symtab
1253 Enable display of per-command gdb resource usage.
1255 remove-symbol-file FILENAME
1256 remove-symbol-file -a ADDRESS
1257 Remove a symbol file added via add-symbol-file. The file to remove
1258 can be identified by its filename or by an address that lies within
1259 the boundaries of this symbol file in memory.
1262 info exceptions REGEXP
1263 Display the list of Ada exceptions defined in the program being
1264 debugged. If provided, only the exceptions whose names match REGEXP
1269 set debug symfile off|on
1271 Control display of debugging info regarding reading symbol files and
1272 symbol tables within those files
1274 set print raw frame-arguments
1275 show print raw frame-arguments
1276 Set/show whether to print frame arguments in raw mode,
1277 disregarding any defined pretty-printers.
1279 set remote trace-status-packet
1280 show remote trace-status-packet
1281 Set/show the use of remote protocol qTStatus packet.
1285 Control display of debugging messages related to Nios II targets.
1289 Control whether target-assisted range stepping is enabled.
1291 set startup-with-shell
1292 show startup-with-shell
1293 Specifies whether Unix child processes are started via a shell or
1298 Use the target memory cache for accesses to the code segment. This
1299 improves performance of remote debugging (particularly disassembly).
1301 * You can now use a literal value 'unlimited' for options that
1302 interpret 0 or -1 as meaning "unlimited". E.g., "set
1303 trace-buffer-size unlimited" is now an alias for "set
1304 trace-buffer-size -1" and "set height unlimited" is now an alias for
1307 * The "set debug symtab-create" debugging option of GDB has been changed to
1308 accept a verbosity level. 0 means "off", 1 provides basic debugging
1309 output, and values of 2 or greater provides more verbose output.
1311 * New command-line options
1313 Display the details of GDB configure-time options.
1315 * The command 'tsave' can now support new option '-ctf' to save trace
1316 buffer in Common Trace Format.
1318 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1321 * GDB now implements the the C++ 'typeid' operator.
1323 * The new convenience variable $_exception holds the exception being
1324 thrown or caught at an exception-related catchpoint.
1326 * The exception-related catchpoints, like "catch throw", now accept a
1327 regular expression which can be used to filter exceptions by type.
1329 * The new convenience variable $_exitsignal is automatically set to
1330 the terminating signal number when the program being debugged dies
1331 due to an uncaught signal.
1335 ** All MI commands now accept an optional "--language" option.
1336 Support for this feature can be verified by using the "-list-features"
1337 command, which should contain "language-option".
1339 ** The new command -info-gdb-mi-command allows the user to determine
1340 whether a GDB/MI command is supported or not.
1342 ** The "^error" result record returned when trying to execute an undefined
1343 GDB/MI command now provides a variable named "code" whose content is the
1344 "undefined-command" error code. Support for this feature can be verified
1345 by using the "-list-features" command, which should contain
1346 "undefined-command-error-code".
1348 ** The -trace-save MI command can optionally save trace buffer in Common
1351 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1353 ** The command -data-list-register-values now accepts an optional
1354 "--skip-unavailable" option. When used, only the available registers
1357 ** The new command -trace-frame-collected dumps collected variables,
1358 computed expressions, tvars, memory and registers in a traceframe.
1360 ** The commands -stack-list-locals, -stack-list-arguments and
1361 -stack-list-variables now accept an option "--skip-unavailable".
1362 When used, only the available locals or arguments are displayed.
1364 ** The -exec-run command now accepts an optional "--start" option.
1365 When used, the command follows the same semantics as the "start"
1366 command, stopping the program's execution at the start of its
1367 main subprogram. Support for this feature can be verified using
1368 the "-list-features" command, which should contain
1369 "exec-run-start-option".
1371 ** The new commands -catch-assert and -catch-exceptions insert
1372 catchpoints stopping the program when Ada exceptions are raised.
1374 ** The new command -info-ada-exceptions provides the equivalent of
1375 the new "info exceptions" command.
1377 * New system-wide configuration scripts
1378 A GDB installation now provides scripts suitable for use as system-wide
1379 configuration scripts for the following systems:
1383 * GDB now supports target-assigned range stepping with remote targets.
1384 This improves the performance of stepping source lines by reducing
1385 the number of control packets from/to GDB. See "New remote packets"
1388 * GDB now understands the element 'tvar' in the XML traceframe info.
1389 It has the id of the collected trace state variables.
1391 * On S/390 targets that provide the transactional-execution feature,
1392 the program interruption transaction diagnostic block (TDB) is now
1393 represented as a number of additional "registers" in GDB.
1395 * New remote packets
1399 The vCont packet supports a new 'r' action, that tells the remote
1400 stub to step through an address range itself, without GDB
1401 involvemement at each single-step.
1403 qXfer:libraries-svr4:read's annex
1404 The previously unused annex of the qXfer:libraries-svr4:read packet
1405 is now used to support passing an argument list. The remote stub
1406 reports support for this argument list to GDB's qSupported query.
1407 The defined arguments are "start" and "prev", used to reduce work
1408 necessary for library list updating, resulting in significant
1411 * New features in the GDB remote stub, GDBserver
1413 ** GDBserver now supports target-assisted range stepping. Currently
1414 enabled on x86/x86_64 GNU/Linux targets.
1416 ** GDBserver now adds element 'tvar' in the XML in the reply to
1417 'qXfer:traceframe-info:read'. It has the id of the collected
1418 trace state variables.
1420 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1423 * New 'z' formatter for printing and examining memory, this displays the
1424 value as hexadecimal zero padded on the left to the size of the type.
1426 * GDB can now use Windows x64 unwinding data.
1428 * The "set remotebaud" command has been replaced by "set serial baud".
1429 Similarly, "show remotebaud" has been replaced by "show serial baud".
1430 The "set remotebaud" and "show remotebaud" commands are still available
1431 to provide backward compatibility with older versions of GDB.
1433 *** Changes in GDB 7.6
1435 * Target record has been renamed to record-full.
1436 Record/replay is now enabled with the "record full" command.
1437 This also affects settings that are associated with full record/replay
1438 that have been moved from "set/show record" to "set/show record full":
1440 set|show record full insn-number-max
1441 set|show record full stop-at-limit
1442 set|show record full memory-query
1444 * A new record target "record-btrace" has been added. The new target
1445 uses hardware support to record the control-flow of a process. It
1446 does not support replaying the execution, but it implements the
1447 below new commands for investigating the recorded execution log.
1448 This new recording method can be enabled using:
1452 The "record-btrace" target is only available on Intel Atom processors
1453 and requires a Linux kernel 2.6.32 or later.
1455 * Two new commands have been added for record/replay to give information
1456 about the recorded execution without having to replay the execution.
1457 The commands are only supported by "record btrace".
1459 record instruction-history prints the execution history at
1460 instruction granularity
1462 record function-call-history prints the execution history at
1463 function granularity
1465 * New native configurations
1467 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1468 FreeBSD/powerpc powerpc*-*-freebsd
1469 x86_64/Cygwin x86_64-*-cygwin*
1470 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1474 ARM AArch64 aarch64*-*-elf
1475 ARM AArch64 GNU/Linux aarch64*-*-linux
1476 Lynx 178 PowerPC powerpc-*-lynx*178
1477 x86_64/Cygwin x86_64-*-cygwin*
1478 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1480 * If the configured location of system.gdbinit file (as given by the
1481 --with-system-gdbinit option at configure time) is in the
1482 data-directory (as specified by --with-gdb-datadir at configure
1483 time) or in one of its subdirectories, then GDB will look for the
1484 system-wide init file in the directory specified by the
1485 --data-directory command-line option.
1487 * New command line options:
1489 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1490 other initialization files, unlike -nx which disables all of them.
1492 * Removed command line options
1494 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1497 * The 'ptype' and 'whatis' commands now accept an argument to control
1500 * 'info proc' now works on some core files.
1504 ** Vectors can be created with gdb.Type.vector.
1506 ** Python's atexit.register now works in GDB.
1508 ** Types can be pretty-printed via a Python API.
1510 ** Python 3 is now supported (in addition to Python 2.4 or later)
1512 ** New class gdb.Architecture exposes GDB's internal representation
1513 of architecture in the Python API.
1515 ** New method Frame.architecture returns the gdb.Architecture object
1516 corresponding to the frame's architecture.
1518 * New Python-based convenience functions:
1520 ** $_memeq(buf1, buf2, length)
1521 ** $_streq(str1, str2)
1523 ** $_regex(str, regex)
1525 * The 'cd' command now defaults to using '~' (the home directory) if not
1528 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1529 default for GCC since November 2000.
1531 * The command 'forward-search' can now be abbreviated as 'fo'.
1533 * The command 'info tracepoints' can now display 'installed on target'
1534 or 'not installed on target' for each non-pending location of tracepoint.
1536 * New configure options
1538 --enable-libmcheck/--disable-libmcheck
1539 By default, development versions are built with -lmcheck on hosts
1540 that support it, in order to help track memory corruption issues.
1541 Release versions, on the other hand, are built without -lmcheck
1542 by default. The --enable-libmcheck/--disable-libmcheck configure
1543 options allow the user to override that default.
1544 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1545 This configure option allows the user to build GDB with
1546 libbabeltrace using which GDB can read Common Trace Format data.
1548 * New commands (for set/show, see "New options" below)
1551 Catch signals. This is similar to "handle", but allows commands and
1552 conditions to be attached.
1555 List the BFDs known to GDB.
1557 python-interactive [command]
1559 Start a Python interactive prompt, or evaluate the optional command
1560 and print the result of expressions.
1563 "py" is a new alias for "python".
1565 enable type-printer [name]...
1566 disable type-printer [name]...
1567 Enable or disable type printers.
1571 ** For the Renesas Super-H architecture, the "regs" command has been removed
1572 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1577 set print type methods (on|off)
1578 show print type methods
1579 Control whether method declarations are displayed by "ptype".
1580 The default is to show them.
1582 set print type typedefs (on|off)
1583 show print type typedefs
1584 Control whether typedef definitions are displayed by "ptype".
1585 The default is to show them.
1587 set filename-display basename|relative|absolute
1588 show filename-display
1589 Control the way in which filenames is displayed.
1590 The default is "relative", which preserves previous behavior.
1592 set trace-buffer-size
1593 show trace-buffer-size
1594 Request target to change the size of trace buffer.
1596 set remote trace-buffer-size-packet auto|on|off
1597 show remote trace-buffer-size-packet
1598 Control the use of the remote protocol `QTBuffer:size' packet.
1602 Control display of debugging messages related to ARM AArch64.
1605 set debug coff-pe-read
1606 show debug coff-pe-read
1607 Control display of debugging messages related to reading of COFF/PE
1612 Control display of debugging messages related to Mach-O symbols
1615 set debug notification
1616 show debug notification
1617 Control display of debugging info for async remote notification.
1621 ** Command parameter changes are now notified using new async record
1622 "=cmd-param-changed".
1623 ** Trace frame changes caused by command "tfind" are now notified using
1624 new async record "=traceframe-changed".
1625 ** The creation, deletion and modification of trace state variables
1626 are now notified using new async records "=tsv-created",
1627 "=tsv-deleted" and "=tsv-modified".
1628 ** The start and stop of process record are now notified using new
1629 async record "=record-started" and "=record-stopped".
1630 ** Memory changes are now notified using new async record
1632 ** The data-disassemble command response will include a "fullname" field
1633 containing the absolute file name when source has been requested.
1634 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1635 command, to allow pattern filling of memory areas.
1636 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1637 library load/unload events.
1638 ** The response to breakpoint commands and breakpoint async records
1639 includes an "installed" field containing a boolean state about each
1640 non-pending tracepoint location is whether installed on target or not.
1641 ** Output of the "-trace-status" command includes a "trace-file" field
1642 containing the name of the trace file being examined. This field is
1643 optional, and only present when examining a trace file.
1644 ** The "fullname" field is now always present along with the "file" field,
1645 even if the file cannot be found by GDB.
1647 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1648 You must have the LZMA library available when configuring GDB for this
1649 feature to be enabled. For more information, see:
1650 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1652 * New remote packets
1655 Set the size of trace buffer. The remote stub reports support for this
1656 packet to gdb's qSupported query.
1659 Enable Branch Trace Store (BTS)-based branch tracing for the current
1660 thread. The remote stub reports support for this packet to gdb's
1664 Disable branch tracing for the current thread. The remote stub reports
1665 support for this packet to gdb's qSupported query.
1668 Read the traced branches for the current thread. The remote stub
1669 reports support for this packet to gdb's qSupported query.
1671 *** Changes in GDB 7.5
1673 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1674 for more x32 ABI info.
1676 * GDB now supports access to MIPS DSP registers on Linux targets.
1678 * GDB now supports debugging microMIPS binaries.
1680 * The "info os" command on GNU/Linux can now display information on
1681 several new classes of objects managed by the operating system:
1682 "info os procgroups" lists process groups
1683 "info os files" lists file descriptors
1684 "info os sockets" lists internet-domain sockets
1685 "info os shm" lists shared-memory regions
1686 "info os semaphores" lists semaphores
1687 "info os msg" lists message queues
1688 "info os modules" lists loaded kernel modules
1690 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1691 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1692 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1693 options and inspect the probe arguments using the new $_probe_arg family
1694 of convenience variables. You can obtain more information about SystemTap
1695 in <http://sourceware.org/systemtap/>.
1697 * GDB now supports reversible debugging on ARM, it allows you to
1698 debug basic ARM and THUMB instructions, and provides
1699 record/replay support.
1701 * The option "symbol-reloading" has been deleted as it is no longer used.
1705 ** GDB commands implemented in Python can now be put in command class
1708 ** The "maint set python print-stack on|off" is now deleted.
1710 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1711 apply "flag enum"-style pretty-printing to any enum.
1713 ** gdb.lookup_symbol can now work when there is no current frame.
1715 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1716 the source at which the symbol was defined.
1718 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1719 method 'value'. The former indicates whether the symbol needs a
1720 frame in order to compute its value, and the latter computes the
1723 ** A new method 'referenced_value' on gdb.Value objects which can
1724 dereference pointer as well as C++ reference values.
1726 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1727 which return the global and static blocks (as gdb.Block objects),
1728 of the underlying symbol table, respectively.
1730 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1731 object associated with a PC value.
1733 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1734 of the address range occupied by code for the current source line.
1736 * Go language support.
1737 GDB now supports debugging programs written in the Go programming
1740 * GDBserver now supports stdio connections.
1741 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1743 * The binary "gdbtui" can no longer be built or installed.
1744 Use "gdb -tui" instead.
1746 * GDB will now print "flag" enums specially. A flag enum is one where
1747 all the enumerator values have no bits in common when pairwise
1748 "and"ed. When printing a value whose type is a flag enum, GDB will
1749 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1750 (gdb) print (enum E) 3
1753 * The filename part of a linespec will now match trailing components
1754 of a source file name. For example, "break gcc/expr.c:1000" will
1755 now set a breakpoint in build/gcc/expr.c, but not
1756 build/libcpp/expr.c.
1758 * The "info proc" and "generate-core-file" commands will now also
1759 work on remote targets connected to GDBserver on Linux.
1761 * The command "info catch" has been removed. It has been disabled
1762 since December 2007.
1764 * The "catch exception" and "catch assert" commands now accept
1765 a condition at the end of the command, much like the "break"
1766 command does. For instance:
1768 (gdb) catch exception Constraint_Error if Barrier = True
1770 Previously, it was possible to add a condition to such catchpoints,
1771 but it had to be done as a second step, after the catchpoint had been
1772 created, using the "condition" command.
1774 * The "info static-tracepoint-marker" command will now also work on
1775 native Linux targets with in-process agent.
1777 * GDB can now set breakpoints on inlined functions.
1779 * The .gdb_index section has been updated to include symbols for
1780 inlined functions. GDB will ignore older .gdb_index sections by
1781 default, which could cause symbol files to be loaded more slowly
1782 until their .gdb_index sections can be recreated. The new command
1783 "set use-deprecated-index-sections on" will cause GDB to use any older
1784 .gdb_index sections it finds. This will restore performance, but the
1785 ability to set breakpoints on inlined functions will be lost in symbol
1786 files with older .gdb_index sections.
1788 The .gdb_index section has also been updated to record more information
1789 about each symbol. This speeds up the "info variables", "info functions"
1790 and "info types" commands when used with programs having the .gdb_index
1791 section, as well as speeding up debugging with shared libraries using
1792 the .gdb_index section.
1794 * Ada support for GDB/MI Variable Objects has been added.
1796 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1801 ** New command -info-os is the MI equivalent of "info os".
1803 ** Output logs ("set logging" and related) now include MI output.
1807 ** "set use-deprecated-index-sections on|off"
1808 "show use-deprecated-index-sections on|off"
1809 Controls the use of deprecated .gdb_index sections.
1811 ** "catch load" and "catch unload" can be used to stop when a shared
1812 library is loaded or unloaded, respectively.
1814 ** "enable count" can be used to auto-disable a breakpoint after
1817 ** "info vtbl" can be used to show the virtual method tables for
1818 C++ and Java objects.
1820 ** "explore" and its sub commands "explore value" and "explore type"
1821 can be used to recursively explore values and types of
1822 expressions. These commands are available only if GDB is
1823 configured with '--with-python'.
1825 ** "info auto-load" shows status of all kinds of auto-loaded files,
1826 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1827 sequences of commands files, "info auto-load python-scripts"
1828 shows status of auto-loading Python script files,
1829 "info auto-load local-gdbinit" shows status of loading init file
1830 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1831 status of inferior specific thread debugging shared library loading.
1833 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1834 and "show auto-load-scripts" commands have been deprecated, use their
1835 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1836 and "show auto-load python-scripts" counterparts instead.
1838 ** "dprintf location,format,args..." creates a dynamic printf, which
1839 is basically a breakpoint that does a printf and immediately
1840 resumes your program's execution, so it is like a printf that you
1841 can insert dynamically at runtime instead of at compiletime.
1843 ** "set print symbol"
1845 Controls whether GDB attempts to display the symbol, if any,
1846 corresponding to addresses it prints. This defaults to "on", but
1847 you can set it to "off" to restore GDB's previous behavior.
1849 * Deprecated commands
1851 ** For the Renesas Super-H architecture, the "regs" command has been
1852 deprecated, and "info all-registers" should be used instead.
1856 Renesas RL78 rl78-*-elf
1857 HP OpenVMS ia64 ia64-hp-openvms*
1859 * GDBserver supports evaluation of breakpoint conditions. When
1860 support is advertised by GDBserver, GDB may be told to send the
1861 breakpoint conditions in bytecode form to GDBserver. GDBserver
1862 will only report the breakpoint trigger to GDB when its condition
1867 set mips compression
1868 show mips compression
1869 Select the compressed ISA encoding used in functions that have no symbol
1870 information available. The encoding can be set to either of:
1873 and is updated automatically from ELF file flags if available.
1875 set breakpoint condition-evaluation
1876 show breakpoint condition-evaluation
1877 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1878 GDBserver ("target"). Default option "auto" chooses the most efficient
1880 This option can improve debugger efficiency depending on the speed of the
1884 Disable auto-loading globally.
1887 Show auto-loading setting of all kinds of auto-loaded files.
1889 set auto-load gdb-scripts on|off
1890 show auto-load gdb-scripts
1891 Control auto-loading of GDB canned sequences of commands files.
1893 set auto-load python-scripts on|off
1894 show auto-load python-scripts
1895 Control auto-loading of Python script files.
1897 set auto-load local-gdbinit on|off
1898 show auto-load local-gdbinit
1899 Control loading of init file (.gdbinit) from current directory.
1901 set auto-load libthread-db on|off
1902 show auto-load libthread-db
1903 Control auto-loading of inferior specific thread debugging shared library.
1905 set auto-load scripts-directory <dir1>[:<dir2>...]
1906 show auto-load scripts-directory
1907 Set a list of directories from which to load auto-loaded scripts.
1908 Automatically loaded Python scripts and GDB scripts are located in one
1909 of the directories listed by this option.
1910 The delimiter (':' above) may differ according to the host platform.
1912 set auto-load safe-path <dir1>[:<dir2>...]
1913 show auto-load safe-path
1914 Set a list of directories from which it is safe to auto-load files.
1915 The delimiter (':' above) may differ according to the host platform.
1917 set debug auto-load on|off
1918 show debug auto-load
1919 Control display of debugging info for auto-loading the files above.
1921 set dprintf-style gdb|call|agent
1923 Control the way in which a dynamic printf is performed; "gdb"
1924 requests a GDB printf command, while "call" causes dprintf to call a
1925 function in the inferior. "agent" requests that the target agent
1926 (such as GDBserver) do the printing.
1928 set dprintf-function <expr>
1929 show dprintf-function
1930 set dprintf-channel <expr>
1931 show dprintf-channel
1932 Set the function and optional first argument to the call when using
1933 the "call" style of dynamic printf.
1935 set disconnected-dprintf on|off
1936 show disconnected-dprintf
1937 Control whether agent-style dynamic printfs continue to be in effect
1938 after GDB disconnects.
1940 * New configure options
1942 --with-auto-load-dir
1943 Configure default value for the 'set auto-load scripts-directory'
1944 setting above. It defaults to '$debugdir:$datadir/auto-load',
1945 $debugdir representing global debugging info directories (available
1946 via 'show debug-file-directory') and $datadir representing GDB's data
1947 directory (available via 'show data-directory').
1949 --with-auto-load-safe-path
1950 Configure default value for the 'set auto-load safe-path' setting
1951 above. It defaults to the --with-auto-load-dir setting.
1953 --without-auto-load-safe-path
1954 Set 'set auto-load safe-path' to '/', effectively disabling this
1957 * New remote packets
1959 z0/z1 conditional breakpoints extension
1961 The z0/z1 breakpoint insertion packets have been extended to carry
1962 a list of conditional expressions over to the remote stub depending on the
1963 condition evaluation mode. The use of this extension can be controlled
1964 via the "set remote conditional-breakpoints-packet" command.
1968 Specify the signals which the remote stub may pass to the debugged
1969 program without GDB involvement.
1971 * New command line options
1973 --init-command=FILE, -ix Like --command, -x but execute it
1974 before loading inferior.
1975 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1976 execute it before loading inferior.
1978 *** Changes in GDB 7.4
1980 * GDB now handles ambiguous linespecs more consistently; the existing
1981 FILE:LINE support has been expanded to other types of linespecs. A
1982 breakpoint will now be set on all matching locations in all
1983 inferiors, and locations will be added or removed according to
1986 * GDB now allows you to skip uninteresting functions and files when
1987 stepping with the "skip function" and "skip file" commands.
1989 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1990 and "show remote hardware-watchpoint-length-limit". These allows to
1991 set or show the maximum length limit (in bytes) of a remote
1992 target hardware watchpoint.
1994 This allows e.g. to use "unlimited" hardware watchpoints with the
1995 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1996 watchpoints are slower than real hardware watchpoints but are
1997 significantly faster than gdb software watchpoints.
2001 ** The register_pretty_printer function in module gdb.printing now takes
2002 an optional `replace' argument. If True, the new printer replaces any
2005 ** The "maint set python print-stack on|off" command has been
2006 deprecated and will be deleted in GDB 7.5.
2007 A new command: "set python print-stack none|full|message" has
2008 replaced it. Additionally, the default for "print-stack" is
2009 now "message", which just prints the error message without
2012 ** A prompt substitution hook (prompt_hook) is now available to the
2015 ** A new Python module, gdb.prompt has been added to the GDB Python
2016 modules library. This module provides functionality for
2017 escape sequences in prompts (used by set/show
2018 extended-prompt). These escape sequences are replaced by their
2019 corresponding value.
2021 ** Python commands and convenience-functions located in
2022 'data-directory'/python/gdb/command and
2023 'data-directory'/python/gdb/function are now automatically loaded
2026 ** Blocks now provide four new attributes. global_block and
2027 static_block will return the global and static blocks
2028 respectively. is_static and is_global are boolean attributes
2029 that indicate if the block is one of those two types.
2031 ** Symbols now provide the "type" attribute, the type of the symbol.
2033 ** The "gdb.breakpoint" function has been deprecated in favor of
2036 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2037 of a function. This class is based on the "finish" command
2038 available in the CLI.
2040 ** Type objects for struct and union types now allow access to
2041 the fields using standard Python dictionary (mapping) methods.
2042 For example, "some_type['myfield']" now works, as does
2043 "some_type.items()".
2045 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2048 ** A new function, "deep_items" has been added to the gdb.types
2049 module in the GDB Python modules library. This function returns
2050 an iterator over the fields of a struct or union type. Unlike
2051 the standard Python "iteritems" method, it will recursively traverse
2052 any anonymous fields.
2056 ** "*stopped" events can report several new "reason"s, such as
2059 ** Breakpoint changes are now notified using new async records, like
2060 "=breakpoint-modified".
2062 ** New command -ada-task-info.
2064 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2065 $sdir specifies the default system locations of shared libraries.
2066 $pdir specifies the directory where the libpthread used by the application
2069 GDB no longer looks in $sdir and $pdir after it has searched the directories
2070 mentioned in libthread-db-search-path. If you want to search those
2071 directories, they must be specified in libthread-db-search-path.
2072 The default value of libthread-db-search-path on GNU/Linux and Solaris
2073 systems is now "$sdir:$pdir".
2075 $pdir is not supported by gdbserver, it is currently ignored.
2076 $sdir is supported by gdbserver.
2078 * New configure option --with-iconv-bin.
2079 When using the internationalization support like the one in the GNU C
2080 library, GDB will invoke the "iconv" program to get a list of supported
2081 character sets. If this program lives in a non-standard location, one can
2082 use this option to specify where to find it.
2084 * When natively debugging programs on PowerPC BookE processors running
2085 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2086 watchpoints, which specify a mask in addition to an address to watch.
2087 The mask specifies that some bits of an address (the bits which are
2088 reset in the mask) should be ignored when matching the address accessed
2089 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2090 section in the user manual for more details.
2092 * The new option --once causes GDBserver to stop listening for connections once
2093 the first connection is made. The listening port used by GDBserver will
2094 become available after that.
2096 * New commands "info macros" and "alias" have been added.
2098 * New function parameters suffix @entry specifies value of function parameter
2099 at the time the function got called. Entry values are available only since
2105 "!" is now an alias of the "shell" command.
2106 Note that no space is needed between "!" and SHELL COMMAND.
2110 watch EXPRESSION mask MASK_VALUE
2111 The watch command now supports the mask argument which allows creation
2112 of masked watchpoints, if the current architecture supports this feature.
2114 info auto-load-scripts [REGEXP]
2115 This command was formerly named "maintenance print section-scripts".
2116 It is now generally useful and is no longer a maintenance-only command.
2118 info macro [-all] [--] MACRO
2119 The info macro command has new options `-all' and `--'. The first for
2120 printing all definitions of a macro. The second for explicitly specifying
2121 the end of arguments and the beginning of the macro name in case the macro
2122 name starts with a hyphen.
2124 collect[/s] EXPRESSIONS
2125 The tracepoint collect command now takes an optional modifier "/s"
2126 that directs it to dereference pointer-to-character types and
2127 collect the bytes of memory up to a zero byte. The behavior is
2128 similar to what you see when you use the regular print command on a
2129 string. An optional integer following the "/s" sets a bound on the
2130 number of bytes that will be collected.
2133 The trace start command now interprets any supplied arguments as a
2134 note to be recorded with the trace run, with an effect similar to
2135 setting the variable trace-notes.
2138 The trace stop command now interprets any arguments as a note to be
2139 mentioned along with the tstatus report that the trace was stopped
2140 with a command. The effect is similar to setting the variable
2143 * Tracepoints can now be enabled and disabled at any time after a trace
2144 experiment has been started using the standard "enable" and "disable"
2145 commands. It is now possible to start a trace experiment with no enabled
2146 tracepoints; GDB will display a warning, but will allow the experiment to
2147 begin, assuming that tracepoints will be enabled as needed while the trace
2150 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2151 locations with 4-byte instructions, when they were previously
2152 limited to locations with instructions of 5 bytes or longer.
2156 set debug dwarf2-read
2157 show debug dwarf2-read
2158 Turns on or off display of debugging messages related to reading
2159 DWARF debug info. The default is off.
2161 set debug symtab-create
2162 show debug symtab-create
2163 Turns on or off display of debugging messages related to symbol table
2164 creation. The default is off.
2167 show extended-prompt
2168 Set the GDB prompt, and allow escape sequences to be inserted to
2169 display miscellaneous information (see 'help set extended-prompt'
2170 for the list of sequences). This prompt (and any information
2171 accessed through the escape sequences) is updated every time the
2172 prompt is displayed.
2174 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2175 show print entry-values
2176 Set printing of frame argument values at function entry. In some cases
2177 GDB can determine the value of function argument which was passed by the
2178 function caller, even if the value was modified inside the called function.
2180 set debug entry-values
2181 show debug entry-values
2182 Control display of debugging info for determining frame argument values at
2183 function entry and virtual tail call frames.
2185 set basenames-may-differ
2186 show basenames-may-differ
2187 Set whether a source file may have multiple base names.
2188 (A "base name" is the name of a file with the directory part removed.
2189 Example: The base name of "/home/user/hello.c" is "hello.c".)
2190 If set, GDB will canonicalize file names (e.g., expand symlinks)
2191 before comparing them. Canonicalization is an expensive operation,
2192 but it allows the same file be known by more than one base name.
2193 If not set (the default), all source files are assumed to have just
2194 one base name, and gdb will do file name comparisons more efficiently.
2200 Set a user name and notes for the current and any future trace runs.
2201 This is useful for long-running and/or disconnected traces, to
2202 inform others (or yourself) as to who is running the trace, supply
2203 contact information, or otherwise explain what is going on.
2205 set trace-stop-notes
2206 show trace-stop-notes
2207 Set a note attached to the trace run, that is displayed when the
2208 trace has been stopped by a tstop command. This is useful for
2209 instance as an explanation, if you are stopping a trace run that was
2210 started by someone else.
2212 * New remote packets
2216 Dynamically enable a tracepoint in a started trace experiment.
2220 Dynamically disable a tracepoint in a started trace experiment.
2224 Set the user and notes of the trace run.
2228 Query the current status of a tracepoint.
2232 Query the minimum length of instruction at which a fast tracepoint may
2235 * Dcache size (number of lines) and line-size are now runtime-configurable
2236 via "set dcache line" and "set dcache line-size" commands.
2240 Texas Instruments TMS320C6x tic6x-*-*
2244 Renesas RL78 rl78-*-elf
2246 *** Changes in GDB 7.3.1
2248 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2250 *** Changes in GDB 7.3
2252 * GDB has a new command: "thread find [REGEXP]".
2253 It finds the thread id whose name, target id, or thread extra info
2254 matches the given regular expression.
2256 * The "catch syscall" command now works on mips*-linux* targets.
2258 * The -data-disassemble MI command now supports modes 2 and 3 for
2259 dumping the instruction opcodes.
2261 * New command line options
2263 -data-directory DIR Specify DIR as the "data-directory".
2264 This is mostly for testing purposes.
2266 * The "maint set python auto-load on|off" command has been renamed to
2267 "set auto-load-scripts on|off".
2269 * GDB has a new command: "set directories".
2270 It is like the "dir" command except that it replaces the
2271 source path list instead of augmenting it.
2273 * GDB now understands thread names.
2275 On GNU/Linux, "info threads" will display the thread name as set by
2276 prctl or pthread_setname_np.
2278 There is also a new command, "thread name", which can be used to
2279 assign a name internally for GDB to display.
2282 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2283 has been integrated into GDB.
2287 ** The function gdb.Write now accepts an optional keyword 'stream'.
2288 This keyword, when provided, will direct the output to either
2289 stdout, stderr, or GDB's logging output.
2291 ** Parameters can now be be sub-classed in Python, and in particular
2292 you may implement the get_set_doc and get_show_doc functions.
2293 This improves how Parameter set/show documentation is processed
2294 and allows for more dynamic content.
2296 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2297 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2298 have an is_valid method.
2300 ** Breakpoints can now be sub-classed in Python, and in particular
2301 you may implement a 'stop' function that is executed each time
2302 the inferior reaches that breakpoint.
2304 ** New function gdb.lookup_global_symbol looks up a global symbol.
2306 ** GDB values in Python are now callable if the value represents a
2307 function. For example, if 'some_value' represents a function that
2308 takes two integer parameters and returns a value, you can call
2309 that function like so:
2311 result = some_value (10,20)
2313 ** Module gdb.types has been added.
2314 It contains a collection of utilities for working with gdb.Types objects:
2315 get_basic_type, has_field, make_enum_dict.
2317 ** Module gdb.printing has been added.
2318 It contains utilities for writing and registering pretty-printers.
2319 New classes: PrettyPrinter, SubPrettyPrinter,
2320 RegexpCollectionPrettyPrinter.
2321 New function: register_pretty_printer.
2323 ** New commands "info pretty-printers", "enable pretty-printer" and
2324 "disable pretty-printer" have been added.
2326 ** gdb.parameter("directories") is now available.
2328 ** New function gdb.newest_frame returns the newest frame in the
2331 ** The gdb.InferiorThread class has a new "name" attribute. This
2332 holds the thread's name.
2334 ** Python Support for Inferior events.
2335 Python scripts can add observers to be notified of events
2336 occurring in the process being debugged.
2337 The following events are currently supported:
2338 - gdb.events.cont Continue event.
2339 - gdb.events.exited Inferior exited event.
2340 - gdb.events.stop Signal received, and Breakpoint hit events.
2344 ** GDB now puts template parameters in scope when debugging in an
2345 instantiation. For example, if you have:
2347 template<int X> int func (void) { return X; }
2349 then if you step into func<5>, "print X" will show "5". This
2350 feature requires proper debuginfo support from the compiler; it
2351 was added to GCC 4.5.
2353 ** The motion commands "next", "finish", "until", and "advance" now
2354 work better when exceptions are thrown. In particular, GDB will
2355 no longer lose control of the inferior; instead, the GDB will
2356 stop the inferior at the point at which the exception is caught.
2357 This functionality requires a change in the exception handling
2358 code that was introduced in GCC 4.5.
2360 * GDB now follows GCC's rules on accessing volatile objects when
2361 reading or writing target state during expression evaluation.
2362 One notable difference to prior behavior is that "print x = 0"
2363 no longer generates a read of x; the value of the assignment is
2364 now always taken directly from the value being assigned.
2366 * GDB now has some support for using labels in the program's source in
2367 linespecs. For instance, you can use "advance label" to continue
2368 execution to a label.
2370 * GDB now has support for reading and writing a new .gdb_index
2371 section. This section holds a fast index of DWARF debugging
2372 information and can be used to greatly speed up GDB startup and
2373 operation. See the documentation for `save gdb-index' for details.
2375 * The "watch" command now accepts an optional "-location" argument.
2376 When used, this causes GDB to watch the memory referred to by the
2377 expression. Such a watchpoint is never deleted due to it going out
2380 * GDB now supports thread debugging of core dumps on GNU/Linux.
2382 GDB now activates thread debugging using the libthread_db library
2383 when debugging GNU/Linux core dumps, similarly to when debugging
2384 live processes. As a result, when debugging a core dump file, GDB
2385 is now able to display pthread_t ids of threads. For example, "info
2386 threads" shows the same output as when debugging the process when it
2387 was live. In earlier releases, you'd see something like this:
2390 * 1 LWP 6780 main () at main.c:10
2392 While now you see this:
2395 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2397 It is also now possible to inspect TLS variables when debugging core
2400 When debugging a core dump generated on a machine other than the one
2401 used to run GDB, you may need to point GDB at the correct
2402 libthread_db library with the "set libthread-db-search-path"
2403 command. See the user manual for more details on this command.
2405 * When natively debugging programs on PowerPC BookE processors running
2406 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2407 which stop execution of the inferior whenever it executes an instruction
2408 at any address within the specified range. See the "PowerPC Embedded"
2409 section in the user manual for more details.
2411 * New features in the GDB remote stub, GDBserver
2413 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2414 and i686 LynxOS (version 5.x).
2416 ** GDBserver is now supported on Blackfin Linux.
2418 * New native configurations
2420 ia64 HP-UX ia64-*-hpux*
2424 Analog Devices, Inc. Blackfin Processor bfin-*
2426 * Ada task switching is now supported on sparc-elf targets when
2427 debugging a program using the Ravenscar Profile. For more information,
2428 see the "Tasking Support when using the Ravenscar Profile" section
2429 in the GDB user manual.
2431 * Guile support was removed.
2433 * New features in the GNU simulator
2435 ** The --map-info flag lists all known core mappings.
2437 ** CFI flashes may be simulated via the "cfi" device.
2439 *** Changes in GDB 7.2
2441 * Shared library support for remote targets by default
2443 When GDB is configured for a generic, non-OS specific target, like
2444 for example, --target=arm-eabi or one of the many *-*-elf targets,
2445 GDB now queries remote stubs for loaded shared libraries using the
2446 `qXfer:libraries:read' packet. Previously, shared library support
2447 was always disabled for such configurations.
2451 ** Argument Dependent Lookup (ADL)
2453 In C++ ADL lookup directs function search to the namespaces of its
2454 arguments even if the namespace has not been imported.
2464 Here the compiler will search for `foo' in the namespace of 'b'
2465 and find A::foo. GDB now supports this. This construct is commonly
2466 used in the Standard Template Library for operators.
2468 ** Improved User Defined Operator Support
2470 In addition to member operators, GDB now supports lookup of operators
2471 defined in a namespace and imported with a `using' directive, operators
2472 defined in the global scope, operators imported implicitly from an
2473 anonymous namespace, and the ADL operators mentioned in the previous
2475 GDB now also supports proper overload resolution for all the previously
2476 mentioned flavors of operators.
2478 ** static const class members
2480 Printing of static const class members that are initialized in the
2481 class definition has been fixed.
2483 * Windows Thread Information Block access.
2485 On Windows targets, GDB now supports displaying the Windows Thread
2486 Information Block (TIB) structure. This structure is visible either
2487 by using the new command `info w32 thread-information-block' or, by
2488 dereferencing the new convenience variable named `$_tlb', a
2489 thread-specific pointer to the TIB. This feature is also supported
2490 when remote debugging using GDBserver.
2492 * Static tracepoints
2494 Static tracepoints are calls in the user program into a tracing
2495 library. One such library is a port of the LTTng kernel tracer to
2496 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2497 When debugging with GDBserver, GDB now supports combining the GDB
2498 tracepoint machinery with such libraries. For example: the user can
2499 use GDB to probe a static tracepoint marker (a call from the user
2500 program into the tracing library) with the new "strace" command (see
2501 "New commands" below). This creates a "static tracepoint" in the
2502 breakpoint list, that can be manipulated with the same feature set
2503 as fast and regular tracepoints. E.g., collect registers, local and
2504 global variables, collect trace state variables, and define
2505 tracepoint conditions. In addition, the user can collect extra
2506 static tracepoint marker specific data, by collecting the new
2507 $_sdata internal variable. When analyzing the trace buffer, you can
2508 inspect $_sdata like any other variable available to GDB. For more
2509 information, see the "Tracepoints" chapter in GDB user manual. New
2510 remote packets have been defined to support static tracepoints, see
2511 the "New remote packets" section below.
2513 * Better reconstruction of tracepoints after disconnected tracing
2515 GDB will attempt to download the original source form of tracepoint
2516 definitions when starting a trace run, and then will upload these
2517 upon reconnection to the target, resulting in a more accurate
2518 reconstruction of the tracepoints that are in use on the target.
2522 You can now exercise direct control over the ways that GDB can
2523 affect your program. For instance, you can disallow the setting of
2524 breakpoints, so that the program can run continuously (assuming
2525 non-stop mode). In addition, the "observer" variable is available
2526 to switch all of the different controls; in observer mode, GDB
2527 cannot affect the target's behavior at all, which is useful for
2528 tasks like diagnosing live systems in the field.
2530 * The new convenience variable $_thread holds the number of the
2533 * New remote packets
2537 Return the address of the Windows Thread Information Block of a given thread.
2541 In response to several of the tracepoint packets, the target may now
2542 also respond with a number of intermediate `qRelocInsn' request
2543 packets before the final result packet, to have GDB handle
2544 relocating an instruction to execute at a different address. This
2545 is particularly useful for stubs that support fast tracepoints. GDB
2546 reports support for this feature in the qSupported packet.
2550 List static tracepoint markers in the target program.
2554 List static tracepoint markers at a given address in the target
2557 qXfer:statictrace:read
2559 Read the static trace data collected (by a `collect $_sdata'
2560 tracepoint action). The remote stub reports support for this packet
2561 to gdb's qSupported query.
2565 Send the current settings of GDB's permission flags.
2569 Send part of the source (textual) form of a tracepoint definition,
2570 which includes location, conditional, and action list.
2572 * The source command now accepts a -s option to force searching for the
2573 script in the source search path even if the script name specifies
2576 * New features in the GDB remote stub, GDBserver
2578 - GDBserver now support tracepoints (including fast tracepoints, and
2579 static tracepoints). The feature is currently supported by the
2580 i386-linux and amd64-linux builds. See the "Tracepoints support
2581 in gdbserver" section in the manual for more information.
2583 GDBserver JIT compiles the tracepoint's conditional agent
2584 expression bytecode into native code whenever possible for low
2585 overhead dynamic tracepoints conditionals. For such tracepoints,
2586 an expression that examines program state is evaluated when the
2587 tracepoint is reached, in order to determine whether to capture
2588 trace data. If the condition is simple and false, processing the
2589 tracepoint finishes very quickly and no data is gathered.
2591 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2592 for static tracepoints support.
2594 - GDBserver now supports x86_64 Windows 64-bit debugging.
2596 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2597 it understands register description.
2599 * The --batch flag now disables pagination and queries.
2601 * X86 general purpose registers
2603 GDB now supports reading/writing byte, word and double-word x86
2604 general purpose registers directly. This means you can use, say,
2605 $ah or $ax to refer, respectively, to the byte register AH and
2606 16-bit word register AX that are actually portions of the 32-bit
2607 register EAX or 64-bit register RAX.
2609 * The `commands' command now accepts a range of breakpoints to modify.
2610 A plain `commands' following a command that creates multiple
2611 breakpoints affects all the breakpoints set by that command. This
2612 applies to breakpoints set by `rbreak', and also applies when a
2613 single `break' command creates multiple breakpoints (e.g.,
2614 breakpoints on overloaded c++ functions).
2616 * The `rbreak' command now accepts a filename specification as part of
2617 its argument, limiting the functions selected by the regex to those
2618 in the specified file.
2620 * Support for remote debugging Windows and SymbianOS shared libraries
2621 from Unix hosts has been improved. Non Windows GDB builds now can
2622 understand target reported file names that follow MS-DOS based file
2623 system semantics, such as file names that include drive letters and
2624 use the backslash character as directory separator. This makes it
2625 possible to transparently use the "set sysroot" and "set
2626 solib-search-path" on Unix hosts to point as host copies of the
2627 target's shared libraries. See the new command "set
2628 target-file-system-kind" described below, and the "Commands to
2629 specify files" section in the user manual for more information.
2633 eval template, expressions...
2634 Convert the values of one or more expressions under the control
2635 of the string template to a command line, and call it.
2637 set target-file-system-kind unix|dos-based|auto
2638 show target-file-system-kind
2639 Set or show the assumed file system kind for target reported file
2642 save breakpoints <filename>
2643 Save all current breakpoint definitions to a file suitable for use
2644 in a later debugging session. To read the saved breakpoint
2645 definitions, use the `source' command.
2647 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2650 info static-tracepoint-markers
2651 Display information about static tracepoint markers in the target.
2653 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2654 Define a static tracepoint by probing a marker at the given
2655 function, line, address, or marker ID.
2659 Enable and disable observer mode.
2661 set may-write-registers on|off
2662 set may-write-memory on|off
2663 set may-insert-breakpoints on|off
2664 set may-insert-tracepoints on|off
2665 set may-insert-fast-tracepoints on|off
2666 set may-interrupt on|off
2667 Set individual permissions for GDB effects on the target. Note that
2668 some of these settings can have undesirable or surprising
2669 consequences, particularly when changed in the middle of a session.
2670 For instance, disabling the writing of memory can prevent
2671 breakpoints from being inserted, cause single-stepping to fail, or
2672 even crash your program, if you disable after breakpoints have been
2673 inserted. However, GDB should not crash.
2675 set record memory-query on|off
2676 show record memory-query
2677 Control whether to stop the inferior if memory changes caused
2678 by an instruction cannot be recorded.
2683 The disassemble command now supports "start,+length" form of two arguments.
2687 ** GDB now provides a new directory location, called the python directory,
2688 where Python scripts written for GDB can be installed. The location
2689 of that directory is <data-directory>/python, where <data-directory>
2690 is the GDB data directory. For more details, see section `Scripting
2691 GDB using Python' in the manual.
2693 ** The GDB Python API now has access to breakpoints, symbols, symbol
2694 tables, program spaces, inferiors, threads and frame's code blocks.
2695 Additionally, GDB Parameters can now be created from the API, and
2696 manipulated via set/show in the CLI.
2698 ** New functions gdb.target_charset, gdb.target_wide_charset,
2699 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2701 ** New exception gdb.GdbError.
2703 ** Pretty-printers are now also looked up in the current program space.
2705 ** Pretty-printers can now be individually enabled and disabled.
2707 ** GDB now looks for names of Python scripts to auto-load in a
2708 special section named `.debug_gdb_scripts', in addition to looking
2709 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2711 * Tracepoint actions were unified with breakpoint commands. In particular,
2712 there are no longer differences in "info break" output for breakpoints and
2713 tracepoints and the "commands" command can be used for both tracepoints and
2714 regular breakpoints.
2718 ARM Symbian arm*-*-symbianelf*
2720 * D language support.
2721 GDB now supports debugging programs written in the D programming
2724 * GDB now supports the extended ptrace interface for PowerPC which is
2725 available since Linux kernel version 2.6.34. This automatically enables
2726 any hardware breakpoints and additional hardware watchpoints available in
2727 the processor. The old ptrace interface exposes just one hardware
2728 watchpoint and no hardware breakpoints.
2730 * GDB is now able to use the Data Value Compare (DVC) register available on
2731 embedded PowerPC processors to implement in hardware simple watchpoint
2732 conditions of the form:
2734 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2736 This works in native GDB running on Linux kernels with the extended ptrace
2737 interface mentioned above.
2739 *** Changes in GDB 7.1
2743 ** Namespace Support
2745 GDB now supports importing of namespaces in C++. This enables the
2746 user to inspect variables from imported namespaces. Support for
2747 namepace aliasing has also been added. So, if a namespace is
2748 aliased in the current scope (e.g. namepace C=A; ) the user can
2749 print variables using the alias (e.g. (gdb) print C::x).
2753 All known bugs relating to the printing of virtual base class were
2754 fixed. It is now possible to call overloaded static methods using a
2759 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2760 and reinterpret_cast<> are now handled by the C++ expression parser.
2764 Xilinx MicroBlaze microblaze-*-*
2769 Xilinx MicroBlaze microblaze
2772 * Multi-program debugging.
2774 GDB now has support for multi-program (a.k.a. multi-executable or
2775 multi-exec) debugging. This allows for debugging multiple inferiors
2776 simultaneously each running a different program under the same GDB
2777 session. See "Debugging Multiple Inferiors and Programs" in the
2778 manual for more information. This implied some user visible changes
2779 in the multi-inferior support. For example, "info inferiors" now
2780 lists inferiors that are not running yet or that have exited
2781 already. See also "New commands" and "New options" below.
2783 * New tracing features
2785 GDB's tracepoint facility now includes several new features:
2787 ** Trace state variables
2789 GDB tracepoints now include support for trace state variables, which
2790 are variables managed by the target agent during a tracing
2791 experiment. They are useful for tracepoints that trigger each
2792 other, so for instance one tracepoint can count hits in a variable,
2793 and then a second tracepoint has a condition that is true when the
2794 count reaches a particular value. Trace state variables share the
2795 $-syntax of GDB convenience variables, and can appear in both
2796 tracepoint actions and condition expressions. Use the "tvariable"
2797 command to create, and "info tvariables" to view; see "Trace State
2798 Variables" in the manual for more detail.
2802 GDB now includes an option for defining fast tracepoints, which
2803 targets may implement more efficiently, such as by installing a jump
2804 into the target agent rather than a trap instruction. The resulting
2805 speedup can be by two orders of magnitude or more, although the
2806 tradeoff is that some program locations on some target architectures
2807 might not allow fast tracepoint installation, for instance if the
2808 instruction to be replaced is shorter than the jump. To request a
2809 fast tracepoint, use the "ftrace" command, with syntax identical to
2810 the regular trace command.
2812 ** Disconnected tracing
2814 It is now possible to detach GDB from the target while it is running
2815 a trace experiment, then reconnect later to see how the experiment
2816 is going. In addition, a new variable disconnected-tracing lets you
2817 tell the target agent whether to continue running a trace if the
2818 connection is lost unexpectedly.
2822 GDB now has the ability to save the trace buffer into a file, and
2823 then use that file as a target, similarly to you can do with
2824 corefiles. You can select trace frames, print data that was
2825 collected in them, and use tstatus to display the state of the
2826 tracing run at the moment that it was saved. To create a trace
2827 file, use "tsave <filename>", and to use it, do "target tfile
2830 ** Circular trace buffer
2832 You can ask the target agent to handle the trace buffer as a
2833 circular buffer, discarding the oldest trace frames to make room for
2834 newer ones, by setting circular-trace-buffer to on. This feature may
2835 not be available for all target agents.
2840 The disassemble command, when invoked with two arguments, now requires
2841 the arguments to be comma-separated.
2844 The info variables command now displays variable definitions. Files
2845 which only declare a variable are not shown.
2848 The source command is now capable of sourcing Python scripts.
2849 This feature is dependent on the debugger being build with Python
2852 Related to this enhancement is also the introduction of a new command
2853 "set script-extension" (see below).
2855 * New commands (for set/show, see "New options" below)
2857 record save [<FILENAME>]
2858 Save a file (in core file format) containing the process record
2859 execution log for replay debugging at a later time.
2861 record restore <FILENAME>
2862 Restore the process record execution log that was saved at an
2863 earlier time, for replay debugging.
2865 add-inferior [-copies <N>] [-exec <FILENAME>]
2868 clone-inferior [-copies <N>] [ID]
2869 Make a new inferior ready to execute the same program another
2870 inferior has loaded.
2875 maint info program-spaces
2876 List the program spaces loaded into GDB.
2878 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2879 show remote interrupt-sequence
2880 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2881 as the sequence to the remote target in order to interrupt the execution.
2882 Ctrl-C is a default. Some system prefers BREAK which is high level of
2883 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2884 Magic SysRq g. It is BREAK signal and character 'g'.
2886 set remote interrupt-on-connect [on | off]
2887 show remote interrupt-on-connect
2888 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2889 remote target when gdb connects to it. This is needed when you debug
2892 set remotebreak [on | off]
2894 Deprecated. Use "set/show remote interrupt-sequence" instead.
2896 tvariable $NAME [ = EXP ]
2897 Create or modify a trace state variable.
2900 List trace state variables and their values.
2902 delete tvariable $NAME ...
2903 Delete one or more trace state variables.
2906 Evaluate the given expressions without collecting anything into the
2907 trace buffer. (Valid in tracepoint actions only.)
2909 ftrace FN / FILE:LINE / *ADDR
2910 Define a fast tracepoint at the given function, line, or address.
2912 * New expression syntax
2914 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2915 GDB now parses 0b101010 identically with 42.
2919 set follow-exec-mode new|same
2920 show follow-exec-mode
2921 Control whether GDB reuses the same inferior across an exec call or
2922 creates a new one. This is useful to be able to restart the old
2923 executable after the inferior having done an exec call.
2925 set default-collect EXPR, ...
2926 show default-collect
2927 Define a list of expressions to be collected at each tracepoint.
2928 This is a useful way to ensure essential items are not overlooked,
2929 such as registers or a critical global variable.
2931 set disconnected-tracing
2932 show disconnected-tracing
2933 If set to 1, the target is instructed to continue tracing if it
2934 loses its connection to GDB. If 0, the target is to stop tracing
2937 set circular-trace-buffer
2938 show circular-trace-buffer
2939 If set to on, the target is instructed to use a circular trace buffer
2940 and discard the oldest trace frames instead of stopping the trace due
2941 to a full trace buffer. If set to off, the trace stops when the buffer
2942 fills up. Some targets may not support this.
2944 set script-extension off|soft|strict
2945 show script-extension
2946 If set to "off", the debugger does not perform any script language
2947 recognition, and all sourced files are assumed to be GDB scripts.
2948 If set to "soft" (the default), files are sourced according to
2949 filename extension, falling back to GDB scripts if the first
2951 If set to "strict", files are sourced according to filename extension.
2953 set ada trust-PAD-over-XVS on|off
2954 show ada trust-PAD-over-XVS
2955 If off, activate a workaround against a bug in the debugging information
2956 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2957 the GCC sources for more information about the GNAT encoding and
2958 PAD types in particular). It is always safe to set this option to
2959 off, but this introduces a slight performance penalty. The default
2962 * Python API Improvements
2964 ** GDB provides the new class gdb.LazyString. This is useful in
2965 some pretty-printing cases. The new method gdb.Value.lazy_string
2966 provides a simple way to create objects of this type.
2968 ** The fields returned by gdb.Type.fields now have an
2969 `is_base_class' attribute.
2971 ** The new method gdb.Type.range returns the range of an array type.
2973 ** The new method gdb.parse_and_eval can be used to parse and
2974 evaluate an expression.
2976 * New remote packets
2979 Define a trace state variable.
2982 Get the current value of a trace state variable.
2985 Set desired tracing behavior upon disconnection.
2988 Set the trace buffer to be linear or circular.
2991 Get data about the tracepoints currently in use.
2995 Process record now works correctly with hardware watchpoints.
2997 Multiple bug fixes have been made to the mips-irix port, making it
2998 much more reliable. In particular:
2999 - Debugging threaded applications is now possible again. Previously,
3000 GDB would hang while starting the program, or while waiting for
3001 the program to stop at a breakpoint.
3002 - Attaching to a running process no longer hangs.
3003 - An error occurring while loading a core file has been fixed.
3004 - Changing the value of the PC register now works again. This fixes
3005 problems observed when using the "jump" command, or when calling
3006 a function from GDB, or even when assigning a new value to $pc.
3007 - With the "finish" and "return" commands, the return value for functions
3008 returning a small array is now correctly printed.
3009 - It is now possible to break on shared library code which gets executed
3010 during a shared library init phase (code executed while executing
3011 their .init section). Previously, the breakpoint would have no effect.
3012 - GDB is now able to backtrace through the signal handler for
3013 non-threaded programs.
3015 PIE (Position Independent Executable) programs debugging is now supported.
3016 This includes debugging execution of PIC (Position Independent Code) shared
3017 libraries although for that, it should be possible to run such libraries as an
3020 *** Changes in GDB 7.0
3022 * GDB now has an interface for JIT compilation. Applications that
3023 dynamically generate code can create symbol files in memory and register
3024 them with GDB. For users, the feature should work transparently, and
3025 for JIT developers, the interface is documented in the GDB manual in the
3026 "JIT Compilation Interface" chapter.
3028 * Tracepoints may now be conditional. The syntax is as for
3029 breakpoints; either an "if" clause appended to the "trace" command,
3030 or the "condition" command is available. GDB sends the condition to
3031 the target for evaluation using the same bytecode format as is used
3032 for tracepoint actions.
3034 * The disassemble command now supports: an optional /r modifier, print the
3035 raw instructions in hex as well as in symbolic form, and an optional /m
3036 modifier to print mixed source+assembly.
3038 * Process record and replay
3040 In a architecture environment that supports ``process record and
3041 replay'', ``process record and replay'' target can record a log of
3042 the process execution, and replay it with both forward and reverse
3045 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3046 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3047 set execution-direction {forward|reverse}, for targets that support
3050 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3051 feature is available with a native GDB running on kernel version
3054 * GDB now has support for multi-byte and wide character sets on the
3055 target. Strings whose character type is wchar_t, char16_t, or
3056 char32_t are now correctly printed. GDB supports wide- and unicode-
3057 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3058 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3059 `printf'. This feature requires iconv to work properly; if your
3060 system does not have a working iconv, GDB can use GNU libiconv. See
3061 the installation instructions for more information.
3063 * GDB now supports automatic retrieval of shared library files from
3064 remote targets. To use this feature, specify a system root that begins
3065 with the `remote:' prefix, either via the `set sysroot' command or via
3066 the `--with-sysroot' configure-time option.
3068 * "info sharedlibrary" now takes an optional regex of libraries to show,
3069 and it now reports if a shared library has no debugging information.
3071 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3072 now complete on file names.
3074 * When completing in expressions, gdb will attempt to limit
3075 completions to allowable structure or union fields, where appropriate.
3076 For instance, consider:
3078 # struct example { int f1; double f2; };
3079 # struct example variable;
3082 If the user types TAB at the end of this command line, the available
3083 completions will be "f1" and "f2".
3085 * Inlined functions are now supported. They show up in backtraces, and
3086 the "step", "next", and "finish" commands handle them automatically.
3088 * GDB now supports the token-splicing (##) and stringification (#)
3089 operators when expanding macros. It also supports variable-arity
3092 * GDB now supports inspecting extra signal information, exported by
3093 the new $_siginfo convenience variable. The feature is currently
3094 implemented on linux ARM, i386 and amd64.
3096 * GDB can now display the VFP floating point registers and NEON vector
3097 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3098 can provide these registers (requires Linux 2.6.30 or later). Remote
3099 and simulator targets may also provide them.
3101 * New remote packets
3104 Search memory for a sequence of bytes.
3107 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3108 operation over reliable transport links. Use of this packet is
3109 controlled by the `set remote noack-packet' command.
3112 Kill the process with the specified process ID. Use this in preference
3113 to `k' when multiprocess protocol extensions are supported.
3116 Obtains additional operating system information
3120 Read or write additional signal information.
3122 * Removed remote protocol undocumented extension
3124 An undocumented extension to the remote protocol's `S' stop reply
3125 packet that permited the stub to pass a process id was removed.
3126 Remote servers should use the `T' stop reply packet instead.
3128 * GDB now supports multiple function calling conventions according to the
3129 DWARF-2 DW_AT_calling_convention function attribute.
3131 * The SH target utilizes the aforementioned change to distinguish between gcc
3132 and Renesas calling convention. It also adds the new CLI commands
3133 `set/show sh calling-convention'.
3135 * GDB can now read compressed debug sections, as produced by GNU gold
3136 with the --compress-debug-sections=zlib flag.
3138 * 64-bit core files are now supported on AIX.
3140 * Thread switching is now supported on Tru64.
3142 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3143 which will be allocated using malloc later in program execution.
3145 * The qXfer:libraries:read remote procotol packet now allows passing a
3146 list of section offsets.
3148 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3149 conditions handling signals delivered during attach or thread creation
3150 have also been fixed.
3152 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3153 From the user's standpoint, all unqualified instances of True and False
3154 are treated as the standard definitions, regardless of context.
3156 * GDB now parses C++ symbol and type names more flexibly. For
3159 template<typename T> class C { };
3162 GDB will now correctly handle all of:
3164 ptype C<char const *>
3165 ptype C<char const*>
3166 ptype C<const char *>
3167 ptype C<const char*>
3169 * New features in the GDB remote stub, gdbserver
3171 - The "--wrapper" command-line argument tells gdbserver to use a
3172 wrapper program to launch programs for debugging.
3174 - On PowerPC and S/390 targets, it is now possible to use a single
3175 gdbserver executable to debug both 32-bit and 64-bit programs.
3176 (This requires gdbserver itself to be built as a 64-bit executable.)
3178 - gdbserver uses the new noack protocol mode for TCP connections to
3179 reduce communications latency, if also supported and enabled in GDB.
3181 - Support for the sparc64-linux-gnu target is now included in
3184 - The amd64-linux build of gdbserver now supports debugging both
3185 32-bit and 64-bit programs.
3187 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3188 now support hardware watchpoints, and will use them automatically
3193 GDB now has support for scripting using Python. Whether this is
3194 available is determined at configure time.
3196 New GDB commands can now be written in Python.
3198 * Ada tasking support
3200 Ada tasks can now be inspected in GDB. The following commands have
3204 Print the list of Ada tasks.
3206 Print detailed information about task number N.
3208 Print the task number of the current task.
3210 Switch the context of debugging to task number N.
3212 * Support for user-defined prefixed commands. The "define" command can
3213 add new commands to existing prefixes, e.g. "target".
3215 * Multi-inferior, multi-process debugging.
3217 GDB now has generalized support for multi-inferior debugging. See
3218 "Debugging Multiple Inferiors" in the manual for more information.
3219 Although availability still depends on target support, the command
3220 set is more uniform now. The GNU/Linux specific multi-forks support
3221 has been migrated to this new framework. This implied some user
3222 visible changes; see "New commands" and also "Removed commands"
3225 * Target descriptions can now describe the target OS ABI. See the
3226 "Target Description Format" section in the user manual for more
3229 * Target descriptions can now describe "compatible" architectures
3230 to indicate that the target can execute applications for a different
3231 architecture in addition to those for the main target architecture.
3232 See the "Target Description Format" section in the user manual for
3235 * Multi-architecture debugging.
3237 GDB now includes general supports for debugging applications on
3238 hybrid systems that use more than one single processor architecture
3239 at the same time. Each such hybrid architecture still requires
3240 specific support to be added. The only hybrid architecture supported
3241 in this version of GDB is the Cell Broadband Engine.
3243 * GDB now supports integrated debugging of Cell/B.E. applications that
3244 use both the PPU and SPU architectures. To enable support for hybrid
3245 Cell/B.E. debugging, you need to configure GDB to support both the
3246 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3247 --enable-targets configure option.
3249 * Non-stop mode debugging.
3251 For some targets, GDB now supports an optional mode of operation in
3252 which you can examine stopped threads while other threads continue
3253 to execute freely. This is referred to as non-stop mode, with the
3254 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3255 section in the user manual for more information.
3257 To be able to support remote non-stop debugging, a remote stub needs
3258 to implement the non-stop mode remote protocol extensions, as
3259 described in the "Remote Non-Stop" section of the user manual. The
3260 GDB remote stub, gdbserver, has been adjusted to support these
3261 extensions on linux targets.
3263 * New commands (for set/show, see "New options" below)
3265 catch syscall [NAME(S) | NUMBER(S)]
3266 Catch system calls. Arguments, which should be names of system
3267 calls or their numbers, mean catch only those syscalls. Without
3268 arguments, every syscall will be caught. When the inferior issues
3269 any of the specified syscalls, GDB will stop and announce the system
3270 call, both when it is called and when its call returns. This
3271 feature is currently available with a native GDB running on the
3272 Linux Kernel, under the following architectures: x86, x86_64,
3273 PowerPC and PowerPC64.
3275 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3277 Search memory for a sequence of bytes.
3279 maint set python print-stack
3280 maint show python print-stack
3281 Show a stack trace when an error is encountered in a Python script.
3284 Invoke CODE by passing it to the Python interpreter.
3289 These allow macros to be defined, undefined, and listed
3293 Show operating system information about processes.
3296 List the inferiors currently under GDB's control.
3299 Switch focus to inferior number NUM.
3302 Detach from inferior number NUM.
3305 Kill inferior number NUM.
3309 set spu stop-on-load
3310 show spu stop-on-load
3311 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3313 set spu auto-flush-cache
3314 show spu auto-flush-cache
3315 Control whether to automatically flush the software-managed cache
3316 during Cell/B.E. debugging.
3318 set sh calling-convention
3319 show sh calling-convention
3320 Control the calling convention used when calling SH target functions.
3323 show debug timestamp
3324 Control display of timestamps with GDB debugging output.
3326 set disassemble-next-line
3327 show disassemble-next-line
3328 Control display of disassembled source lines or instructions when
3331 set remote noack-packet
3332 show remote noack-packet
3333 Set/show the use of remote protocol QStartNoAckMode packet. See above
3334 under "New remote packets."
3336 set remote query-attached-packet
3337 show remote query-attached-packet
3338 Control use of remote protocol `qAttached' (query-attached) packet.
3340 set remote read-siginfo-object
3341 show remote read-siginfo-object
3342 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3345 set remote write-siginfo-object
3346 show remote write-siginfo-object
3347 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3350 set remote reverse-continue
3351 show remote reverse-continue
3352 Control use of remote protocol 'bc' (reverse-continue) packet.
3354 set remote reverse-step
3355 show remote reverse-step
3356 Control use of remote protocol 'bs' (reverse-step) packet.
3358 set displaced-stepping
3359 show displaced-stepping
3360 Control displaced stepping mode. Displaced stepping is a way to
3361 single-step over breakpoints without removing them from the debuggee.
3362 Also known as "out-of-line single-stepping".
3365 show debug displaced
3366 Control display of debugging info for displaced stepping.
3368 maint set internal-error
3369 maint show internal-error
3370 Control what GDB does when an internal error is detected.
3372 maint set internal-warning
3373 maint show internal-warning
3374 Control what GDB does when an internal warning is detected.
3379 Use a wrapper program to launch programs for debugging.
3381 set multiple-symbols (all|ask|cancel)
3382 show multiple-symbols
3383 The value of this variable can be changed to adjust the debugger behavior
3384 when an expression or a breakpoint location contains an ambiguous symbol
3385 name (an overloaded function name, for instance).
3387 set breakpoint always-inserted
3388 show breakpoint always-inserted
3389 Keep breakpoints always inserted in the target, as opposed to inserting
3390 them when resuming the target, and removing them when the target stops.
3391 This option can improve debugger performance on slow remote targets.
3393 set arm fallback-mode (arm|thumb|auto)
3394 show arm fallback-mode
3395 set arm force-mode (arm|thumb|auto)
3397 These commands control how ARM GDB determines whether instructions
3398 are ARM or Thumb. The default for both settings is auto, which uses
3399 the current CPSR value for instructions without symbols; previous
3400 versions of GDB behaved as if "set arm fallback-mode arm".
3402 set disable-randomization
3403 show disable-randomization
3404 Standalone programs run with the virtual address space randomization enabled
3405 by default on some platforms. This option keeps the addresses stable across
3406 multiple debugging sessions.
3410 Control whether other threads are stopped or not when some thread hits
3415 Requests that asynchronous execution is enabled in the target, if available.
3416 In this case, it's possible to resume target in the background, and interact
3417 with GDB while the target is running. "show target-async" displays the
3418 current state of asynchronous execution of the target.
3420 set target-wide-charset
3421 show target-wide-charset
3422 The target-wide-charset is the name of the character set that GDB
3423 uses when printing characters whose type is wchar_t.
3425 set tcp auto-retry (on|off)
3427 set tcp connect-timeout
3428 show tcp connect-timeout
3429 These commands allow GDB to retry failed TCP connections to a remote stub
3430 with a specified timeout period; this is useful if the stub is launched
3431 in parallel with GDB but may not be ready to accept connections immediately.
3433 set libthread-db-search-path
3434 show libthread-db-search-path
3435 Control list of directories which GDB will search for appropriate
3438 set schedule-multiple (on|off)
3439 show schedule-multiple
3440 Allow GDB to resume all threads of all processes or only threads of
3441 the current process.
3445 Use more aggressive caching for accesses to the stack. This improves
3446 performance of remote debugging (particularly backtraces) without
3447 affecting correctness.
3449 set interactive-mode (on|off|auto)
3450 show interactive-mode
3451 Control whether GDB runs in interactive mode (on) or not (off).
3452 When in interactive mode, GDB waits for the user to answer all
3453 queries. Otherwise, GDB does not wait and assumes the default
3454 answer. When set to auto (the default), GDB determines which
3455 mode to use based on the stdin settings.
3460 For program forks, this is replaced by the new more generic `info
3461 inferiors' command. To list checkpoints, you can still use the
3462 `info checkpoints' command, which was an alias for the `info forks'
3466 Replaced by the new `inferior' command. To switch between
3467 checkpoints, you can still use the `restart' command, which was an
3468 alias for the `fork' command.
3471 This is removed, since some targets don't have a notion of
3472 processes. To switch between processes, you can still use the
3473 `inferior' command using GDB's own inferior number.
3476 For program forks, this is replaced by the new more generic `kill
3477 inferior' command. To delete a checkpoint, you can still use the
3478 `delete checkpoint' command, which was an alias for the `delete
3482 For program forks, this is replaced by the new more generic `detach
3483 inferior' command. To detach a checkpoint, you can still use the
3484 `detach checkpoint' command, which was an alias for the `detach
3487 * New native configurations
3489 x86/x86_64 Darwin i[34567]86-*-darwin*
3491 x86_64 MinGW x86_64-*-mingw*
3495 Lattice Mico32 lm32-*
3496 x86 DICOS i[34567]86-*-dicos*
3497 x86_64 DICOS x86_64-*-dicos*
3500 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3501 (mingw32ce) debugging.
3507 These commands were actually not implemented on any target.
3509 *** Changes in GDB 6.8
3511 * New native configurations
3513 NetBSD/hppa hppa*-*netbsd*
3514 Xtensa GNU/Linux xtensa*-*-linux*
3518 NetBSD/hppa hppa*-*-netbsd*
3519 Xtensa GNU/Lunux xtensa*-*-linux*
3521 * Change in command line behavior -- corefiles vs. process ids.
3523 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3524 attaching to process NUMBER fails, GDB no longer attempts to open a
3525 core file named NUMBER. Attaching to a program using the -c option
3526 is no longer supported. Instead, use the '-p' or '--pid' options.
3528 * GDB can now be built as a native debugger for debugging Windows x86
3529 (mingw32) Portable Executable (PE) programs.
3531 * Pending breakpoints no longer change their number when their address
3534 * GDB now supports breakpoints with multiple locations,
3535 including breakpoints on C++ constructors, inside C++ templates,
3536 and in inlined functions.
3538 * GDB's ability to debug optimized code has been improved. GDB more
3539 accurately identifies function bodies and lexical blocks that occupy
3540 more than one contiguous range of addresses.
3542 * Target descriptions can now describe registers for PowerPC.
3544 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3545 registers on PowerPC targets.
3547 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3548 targets even when the libthread_db library is not available.
3550 * The GDB remote stub, gdbserver, now supports the new file transfer
3551 commands (remote put, remote get, and remote delete).
3553 * The GDB remote stub, gdbserver, now supports run and attach in
3554 extended-remote mode.
3556 * hppa*64*-*-hpux11* target broken
3557 The debugger is unable to start a program and fails with the following
3558 error: "Error trying to get information about dynamic linker".
3559 The gdb-6.7 release is also affected.
3561 * GDB now supports the --enable-targets= configure option to allow
3562 building a single GDB executable that supports multiple remote
3563 target architectures.
3565 * GDB now supports debugging C and C++ programs which use the
3566 Decimal Floating Point extension. In addition, the PowerPC target
3567 now has a set of pseudo-registers to inspect decimal float values
3568 stored in two consecutive float registers.
3570 * The -break-insert MI command can optionally create pending
3573 * Improved support for debugging Ada
3574 Many improvements to the Ada language support have been made. These
3576 - Better support for Ada2005 interface types
3577 - Improved handling of arrays and slices in general
3578 - Better support for Taft-amendment types
3579 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3581 - Improved command completion in Ada
3584 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3589 set print frame-arguments (all|scalars|none)
3590 show print frame-arguments
3591 The value of this variable can be changed to control which argument
3592 values should be printed by the debugger when displaying a frame.
3597 Transfer files to and from a remote target, and delete remote files.
3604 Transfer files to and from a remote target, and delete remote files.
3606 * New remote packets
3613 Open, close, read, write, and delete files on the remote system.
3616 Attach to an existing process on the remote system, in extended-remote
3620 Run a new process on the remote system, in extended-remote mode.
3622 *** Changes in GDB 6.7
3624 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3625 bfd, libiberty and opcodes, as revealed by static analysis donated by
3626 Coverity, Inc. (http://scan.coverity.com).
3628 * When looking up multiply-defined global symbols, GDB will now prefer the
3629 symbol definition in the current shared library if it was built using the
3630 -Bsymbolic linker option.
3632 * When the Text User Interface (TUI) is not configured, GDB will now
3633 recognize the -tui command-line option and print a message that the TUI
3636 * The GDB remote stub, gdbserver, now has lower overhead for high
3637 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3639 * GDB for MIPS targets now autodetects whether a remote target provides
3640 32-bit or 64-bit register values.
3642 * Support for C++ member pointers has been improved.
3644 * GDB now understands XML target descriptions, which specify the
3645 target's overall architecture. GDB can read a description from
3646 a local file or over the remote serial protocol.
3648 * Vectors of single-byte data use a new integer type which is not
3649 automatically displayed as character or string data.
3651 * The /s format now works with the print command. It displays
3652 arrays of single-byte integers and pointers to single-byte integers
3655 * Target descriptions can now describe target-specific registers,
3656 for architectures which have implemented the support (currently
3657 only ARM, M68K, and MIPS).
3659 * GDB and the GDB remote stub, gdbserver, now support the XScale
3662 * The GDB remote stub, gdbserver, has been updated to support
3663 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3664 has been rewritten to use the standard GDB remote protocol.
3666 * GDB can now step into C++ functions which are called through thunks.
3668 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3670 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3671 layout. It also supports a TextSeg= and DataSeg= response when only
3672 segment base addresses (rather than offsets) are available.
3674 * The /i format now outputs any trailing branch delay slot instructions
3675 immediately following the last instruction within the count specified.
3677 * The GDB remote protocol "T" stop reply packet now supports a
3678 "library" response. Combined with the new "qXfer:libraries:read"
3679 packet, this response allows GDB to debug shared libraries on targets
3680 where the operating system manages the list of loaded libraries (e.g.
3681 Windows and SymbianOS).
3683 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3684 (DLLs) on Windows and Windows CE targets.
3686 * GDB now supports a faster verification that a .debug file matches its binary
3687 according to its build-id signature, if the signature is present.
3693 Enable or disable hardware flow control (RTS/CTS) on the serial port
3694 when debugging using remote targets.
3696 set mem inaccessible-by-default
3697 show mem inaccessible-by-default
3698 If the target supplies a memory map, for instance via the remote
3699 protocol's "qXfer:memory-map:read" packet, setting this variable
3700 prevents GDB from accessing memory outside the memory map. This
3701 is useful for targets with memory mapped registers or which react
3702 badly to accesses of unmapped address space.
3704 set breakpoint auto-hw
3705 show breakpoint auto-hw
3706 If the target supplies a memory map, for instance via the remote
3707 protocol's "qXfer:memory-map:read" packet, setting this variable
3708 lets GDB use hardware breakpoints automatically for memory regions
3709 where it can not use software breakpoints. This covers both the
3710 "break" command and internal breakpoints used for other commands
3711 including "next" and "finish".
3714 catch exception unhandled
3715 Stop the program execution when Ada exceptions are raised.
3718 Stop the program execution when an Ada assertion failed.
3722 Set an alternate system root for target files. This is a more
3723 general version of "set solib-absolute-prefix", which is now
3724 an alias to "set sysroot".
3727 Provide extended SPU facility status information. This set of
3728 commands is available only when debugging the Cell/B.E. SPU
3731 * New native configurations
3733 OpenBSD/sh sh*-*openbsd*
3736 unset tdesc filename
3738 Use the specified local file as an XML target description, and do
3739 not query the target for its built-in description.
3743 OpenBSD/sh sh*-*-openbsd*
3744 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3745 Toshiba Media Processor mep-elf
3747 * New remote packets
3750 Ignore the specified signals; pass them directly to the debugged program
3751 without stopping other threads or reporting them to GDB.
3753 qXfer:features:read:
3754 Read an XML target description from the target, which describes its
3759 Read or write contents of an spufs file on the target system. These
3760 packets are available only on the Cell/B.E. SPU architecture.
3762 qXfer:libraries:read:
3763 Report the loaded shared libraries. Combined with new "T" packet
3764 response, this packet allows GDB to debug shared libraries on
3765 targets where the operating system manages the list of loaded
3766 libraries (e.g. Windows and SymbianOS).
3770 Support for these obsolete configurations has been removed.
3778 i[34567]86-*-lynxos*
3779 i[34567]86-*-netware*
3780 i[34567]86-*-sco3.2v5*
3781 i[34567]86-*-sco3.2v4*
3783 i[34567]86-*-sysv4.2*
3786 i[34567]86-*-unixware2*
3787 i[34567]86-*-unixware*
3796 * Other removed features
3803 Various m68k-only ROM monitors.
3810 Various Renesas ROM monitors and debugging interfaces for SH and
3815 Support for a Macraigor serial interface to on-chip debugging.
3816 GDB does not directly support the newer parallel or USB
3821 A debug information format. The predecessor to DWARF 2 and
3822 DWARF 3, which are still supported.
3824 Support for the HP aCC compiler on HP-UX/PA-RISC
3826 SOM-encapsulated symbolic debugging information, automatic
3827 invocation of pxdb, and the aCC custom C++ ABI. This does not
3828 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3829 with aCC can still be debugged on an assembly level.
3831 MIPS ".pdr" sections
3833 A MIPS-specific format used to describe stack frame layout
3834 in debugging information.
3838 GDB could work with an older version of Guile to debug
3839 the interpreter and Scheme programs running in it.
3841 set mips stack-arg-size
3842 set mips saved-gpreg-size
3844 Use "set mips abi" to control parameter passing for MIPS.
3846 *** Changes in GDB 6.6
3851 Cell Broadband Engine SPU spu-elf
3853 * GDB can now be configured as a cross-debugger targeting native Windows
3854 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3855 running on a Windows system over TCP/IP to debug Windows programs.
3857 * The GDB remote stub, gdbserver, has been updated to support Windows and
3858 Cygwin debugging. Both single-threaded and multi-threaded programs are
3861 * The "set trust-readonly-sections" command works again. This command was
3862 broken in GDB 6.3, 6.4, and 6.5.
3864 * The "load" command now supports writing to flash memory, if the remote
3865 stub provides the required support.
3867 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3868 longer requires symbolic debug information (e.g. DWARF-2).
3873 unset substitute-path
3874 show substitute-path
3875 Manage a list of substitution rules that GDB uses to rewrite the name
3876 of the directories where the sources are located. This can be useful
3877 for instance when the sources were moved to a different location
3878 between compilation and debugging.
3882 Print each CLI command as it is executed. Each command is prefixed with
3883 a number of `+' symbols representing the nesting depth.
3884 The source command now has a `-v' option to enable the same feature.
3888 The ARM Demon monitor support (RDP protocol, "target rdp").
3890 Kernel Object Display, an embedded debugging feature which only worked with
3891 an obsolete version of Cisco IOS.
3893 The 'set download-write-size' and 'show download-write-size' commands.
3895 * New remote packets
3898 Tell a stub about GDB client features, and request remote target features.
3899 The first feature implemented is PacketSize, which allows the target to
3900 specify the size of packets it can handle - to minimize the number of
3901 packets required and improve performance when connected to a remote
3905 Fetch an OS auxilliary vector from the remote stub. This packet is a
3906 more efficient replacement for qPart:auxv:read.
3908 qXfer:memory-map:read:
3909 Fetch a memory map from the remote stub, including information about
3910 RAM, ROM, and flash memory devices.
3915 Erase and program a flash memory device.
3917 * Removed remote packets
3920 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3921 used it, and only gdbserver implemented it.
3923 *** Changes in GDB 6.5
3927 Renesas M32C/M16C m32c-elf
3929 Morpho Technologies ms1 ms1-elf
3933 init-if-undefined Initialize a convenience variable, but
3934 only if it doesn't already have a value.
3936 The following commands are presently only implemented for native GNU/Linux:
3938 checkpoint Save a snapshot of the program state.
3940 restart <n> Return the program state to a
3941 previously saved state.
3943 info checkpoints List currently saved checkpoints.
3945 delete-checkpoint <n> Delete a previously saved checkpoint.
3947 set|show detach-on-fork Tell gdb whether to detach from a newly
3948 forked process, or to keep debugging it.
3950 info forks List forks of the user program that
3951 are available to be debugged.
3953 fork <n> Switch to debugging one of several
3954 forks of the user program that are
3955 available to be debugged.
3957 delete-fork <n> Delete a fork from the list of forks
3958 that are available to be debugged (and
3959 kill the forked process).
3961 detach-fork <n> Delete a fork from the list of forks
3962 that are available to be debugged (and
3963 allow the process to continue).
3967 Morpho Technologies ms2 ms1-elf
3969 * Improved Windows host support
3971 GDB now builds as a cross debugger hosted on i686-mingw32, including
3972 native console support, and remote communications using either
3973 network sockets or serial ports.
3975 * Improved Modula-2 language support
3977 GDB can now print most types in the Modula-2 syntax. This includes:
3978 basic types, set types, record types, enumerated types, range types,
3979 pointer types and ARRAY types. Procedure var parameters are correctly
3980 printed and hexadecimal addresses and character constants are also
3981 written in the Modula-2 syntax. Best results can be obtained by using
3982 GNU Modula-2 together with the -gdwarf-2 command line option.
3986 The ARM rdi-share module.
3988 The Netware NLM debug server.
3990 *** Changes in GDB 6.4
3992 * New native configurations
3994 OpenBSD/arm arm*-*-openbsd*
3995 OpenBSD/mips64 mips64-*-openbsd*
3999 Morpho Technologies ms1 ms1-elf
4001 * New command line options
4003 --batch-silent As for --batch, but totally silent.
4004 --return-child-result The debugger will exist with the same value
4005 the child (debugged) program exited with.
4006 --eval-command COMMAND, -ex COMMAND
4007 Execute a single GDB CLI command. This may be
4008 specified multiple times and in conjunction
4009 with the --command (-x) option.
4011 * Deprecated commands removed
4013 The following commands, that were deprecated in 2000, have been
4017 set|show arm disassembly-flavor set|show arm disassembler
4018 othernames set arm disassembler
4019 set|show remotedebug set|show debug remote
4020 set|show archdebug set|show debug arch
4021 set|show eventdebug set|show debug event
4024 * New BSD user-level threads support
4026 It is now possible to debug programs using the user-level threads
4027 library on OpenBSD and FreeBSD. Currently supported (target)
4030 FreeBSD/amd64 x86_64-*-freebsd*
4031 FreeBSD/i386 i386-*-freebsd*
4032 OpenBSD/i386 i386-*-openbsd*
4034 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4035 are not yet supported.
4037 * New support for Matsushita MN10300 w/sim added
4038 (Work in progress). mn10300-elf.
4040 * REMOVED configurations and files
4042 VxWorks and the XDR protocol *-*-vxworks
4043 Motorola MCORE mcore-*-*
4044 National Semiconductor NS32000 ns32k-*-*
4046 * New "set print array-indexes" command
4048 After turning this setting "on", GDB prints the index of each element
4049 when displaying arrays. The default is "off" to preserve the previous
4052 * VAX floating point support
4054 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4056 * User-defined command support
4058 In addition to using $arg0..$arg9 for argument passing, it is now possible
4059 to use $argc to determine now many arguments have been passed. See the
4060 section on user-defined commands in the user manual for more information.
4062 *** Changes in GDB 6.3:
4064 * New command line option
4066 GDB now accepts -l followed by a number to set the timeout for remote
4069 * GDB works with GCC -feliminate-dwarf2-dups
4071 GDB now supports a more compact representation of DWARF-2 debug
4072 information using DW_FORM_ref_addr references. These are produced
4073 by GCC with the option -feliminate-dwarf2-dups and also by some
4074 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4075 to use -feliminate-dwarf2-dups.
4077 * Internationalization
4079 When supported by the host system, GDB will be built with
4080 internationalization (libintl). The task of marking up the sources is
4081 continued, we're looking forward to our first translation.
4085 Initial support for debugging programs compiled with the GNAT
4086 implementation of the Ada programming language has been integrated
4087 into GDB. In this release, support is limited to expression evaluation.
4089 * New native configurations
4091 GNU/Linux/m32r m32r-*-linux-gnu
4095 GDB's remote protocol now includes support for the 'p' packet. This
4096 packet is used to fetch individual registers from a remote inferior.
4098 * END-OF-LIFE registers[] compatibility module
4100 GDB's internal register infrastructure has been completely rewritten.
4101 The new infrastructure making possible the implementation of key new
4102 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4105 GDB 6.3 will be the last release to include the the registers[]
4106 compatibility module that allowed out-of-date configurations to
4107 continue to work. This change directly impacts the following
4117 powerpc bdm protocol
4119 Unless there is activity to revive these configurations, they will be
4120 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4122 * OBSOLETE configurations and files
4124 Configurations that have been declared obsolete in this release have
4125 been commented out. Unless there is activity to revive these
4126 configurations, the next release of GDB will have their sources
4127 permanently REMOVED.
4136 *** Changes in GDB 6.2.1:
4138 * MIPS `break main; run' gave an heuristic-fence-post warning
4140 When attempting to run even a simple program, a warning about
4141 heuristic-fence-post being hit would be reported. This problem has
4144 * MIPS IRIX 'long double' crashed GDB
4146 When examining a long double variable, GDB would get a segmentation
4147 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4148 IRIX long double values).
4152 A bug in the VAX stack code was causing problems with the "next"
4153 command. This problem has been fixed.
4155 *** Changes in GDB 6.2:
4157 * Fix for ``many threads''
4159 On GNU/Linux systems that use the NPTL threads library, a program
4160 rapidly creating and deleting threads would confuse GDB leading to the
4163 ptrace: No such process.
4164 thread_db_get_info: cannot get thread info: generic error
4166 This problem has been fixed.
4168 * "-async" and "-noasync" options removed.
4170 Support for the broken "-noasync" option has been removed (it caused
4173 * New ``start'' command.
4175 This command runs the program until the begining of the main procedure.
4177 * New BSD Kernel Data Access Library (libkvm) interface
4179 Using ``target kvm'' it is now possible to debug kernel core dumps and
4180 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4181 platforms. Currently supported (native-only) configurations are:
4183 FreeBSD/amd64 x86_64-*-freebsd*
4184 FreeBSD/i386 i?86-*-freebsd*
4185 NetBSD/i386 i?86-*-netbsd*
4186 NetBSD/m68k m68*-*-netbsd*
4187 NetBSD/sparc sparc-*-netbsd*
4188 OpenBSD/amd64 x86_64-*-openbsd*
4189 OpenBSD/i386 i?86-*-openbsd*
4190 OpenBSD/m68k m68*-openbsd*
4191 OpenBSD/sparc sparc-*-openbsd*
4193 * Signal trampoline code overhauled
4195 Many generic problems with GDB's signal handling code have been fixed.
4196 These include: backtraces through non-contiguous stacks; recognition
4197 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4198 call; backtrace through a signal trampoline; step into and out of
4199 signal handlers; and single-stepping in the signal trampoline.
4201 Please note that kernel bugs are a limiting factor here. These
4202 features have been shown to work on an s390 GNU/Linux system that
4203 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4205 * Cygwin support for DWARF 2 added.
4207 * New native configurations
4209 GNU/Linux/hppa hppa*-*-linux*
4210 OpenBSD/hppa hppa*-*-openbsd*
4211 OpenBSD/m68k m68*-*-openbsd*
4212 OpenBSD/m88k m88*-*-openbsd*
4213 OpenBSD/powerpc powerpc-*-openbsd*
4214 NetBSD/vax vax-*-netbsd*
4215 OpenBSD/vax vax-*-openbsd*
4217 * END-OF-LIFE frame compatibility module
4219 GDB's internal frame infrastructure has been completely rewritten.
4220 The new infrastructure making it possible to support key new features
4221 including DWARF 2 Call Frame Information. To aid in the task of
4222 migrating old configurations to this new infrastructure, a
4223 compatibility module, that allowed old configurations to continue to
4224 work, was also included.
4226 GDB 6.2 will be the last release to include this frame compatibility
4227 module. This change directly impacts the following configurations:
4237 Unless there is activity to revive these configurations, they will be
4238 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4240 * REMOVED configurations and files
4242 Sun 3, running SunOS 3 m68*-*-sunos3*
4243 Sun 3, running SunOS 4 m68*-*-sunos4*
4244 Sun 2, running SunOS 3 m68000-*-sunos3*
4245 Sun 2, running SunOS 4 m68000-*-sunos4*
4246 Motorola 680x0 running LynxOS m68*-*-lynxos*
4247 AT&T 3b1/Unix pc m68*-att-*
4248 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4249 decstation mips-dec-* mips-little-*
4250 riscos mips-*-riscos* mips-*-sysv*
4251 sonymips mips-sony-*
4252 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4254 *** Changes in GDB 6.1.1:
4256 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4258 The TUI (Text-mode User Interface) is now built as part of a default
4259 GDB configuration. It is enabled by either selecting the TUI with the
4260 command line option "-i=tui" or by running the separate "gdbtui"
4261 program. For more information on the TUI, see the manual "Debugging
4264 * Pending breakpoint support (also included in GDB 6.1)
4266 Support has been added to allow you to specify breakpoints in shared
4267 libraries that have not yet been loaded. If a breakpoint location
4268 cannot be found, and the "breakpoint pending" option is set to auto,
4269 GDB queries you if you wish to make the breakpoint pending on a future
4270 shared-library load. If and when GDB resolves the breakpoint symbol,
4271 the pending breakpoint is removed as one or more regular breakpoints
4274 Pending breakpoints are very useful for GCJ Java debugging.
4276 * Fixed ISO-C build problems
4278 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4279 non ISO-C code that stopped them being built using a more strict ISO-C
4280 compiler (e.g., IBM's C compiler).
4282 * Fixed build problem on IRIX 5
4284 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4285 wasn't able to compile compile on an IRIX 5 system.
4287 * Added execute permission to gdb/gdbserver/configure
4289 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4290 permission. This bug would cause configure to fail on a number of
4291 systems (Solaris, IRIX). Ref: server/519.
4293 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4295 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4296 has been updated to use constant array sizes.
4298 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4300 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4301 its generated DWARF Call Frame Info. This encoding was causing GDB to
4302 panic, that panic has been fixed. Ref: gdb/1628.
4304 * Fixed a problem when examining parameters in shared library code.
4306 When examining parameters in optimized shared library code generated
4307 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4308 not available''. GDB now correctly displays the variable's value.
4310 *** Changes in GDB 6.1:
4312 * Removed --with-mmalloc
4314 Support for the mmalloc memory manager has been removed, as it
4315 conflicted with the internal gdb byte cache.
4317 * Changes in AMD64 configurations
4319 The AMD64 target now includes the %cs and %ss registers. As a result
4320 the AMD64 remote protocol has changed; this affects the floating-point
4321 and SSE registers. If you rely on those registers for your debugging,
4322 you should upgrade gdbserver on the remote side.
4324 * Revised SPARC target
4326 The SPARC target has been completely revised, incorporating the
4327 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4328 support for LynxOS and SunOS 4 has been dropped. Calling functions
4329 from within GDB on operating systems with a non-executable stack
4330 (Solaris, OpenBSD) now works.
4334 GDB has a new C++ demangler which does a better job on the mangled
4335 names generated by current versions of g++. It also runs faster, so
4336 with this and other changes gdb should now start faster on large C++
4339 * DWARF 2 Location Expressions
4341 GDB support for location expressions has been extended to support function
4342 arguments and frame bases. Older versions of GDB could crash when they
4345 * C++ nested types and namespaces
4347 GDB's support for nested types and namespaces in C++ has been
4348 improved, especially if you use the DWARF 2 debugging format. (This
4349 is the default for recent versions of GCC on most platforms.)
4350 Specifically, if you have a class "Inner" defined within a class or
4351 namespace "Outer", then GDB realizes that the class's name is
4352 "Outer::Inner", not simply "Inner". This should greatly reduce the
4353 frequency of complaints about not finding RTTI symbols. In addition,
4354 if you are stopped at inside of a function defined within a namespace,
4355 GDB modifies its name lookup accordingly.
4357 * New native configurations
4359 NetBSD/amd64 x86_64-*-netbsd*
4360 OpenBSD/amd64 x86_64-*-openbsd*
4361 OpenBSD/alpha alpha*-*-openbsd*
4362 OpenBSD/sparc sparc-*-openbsd*
4363 OpenBSD/sparc64 sparc64-*-openbsd*
4365 * New debugging protocols
4367 M32R with SDI protocol m32r-*-elf*
4369 * "set prompt-escape-char" command deleted.
4371 The command "set prompt-escape-char" has been deleted. This command,
4372 and its very obscure effet on GDB's prompt, was never documented,
4373 tested, nor mentioned in the NEWS file.
4375 * OBSOLETE configurations and files
4377 Configurations that have been declared obsolete in this release have
4378 been commented out. Unless there is activity to revive these
4379 configurations, the next release of GDB will have their sources
4380 permanently REMOVED.
4382 Sun 3, running SunOS 3 m68*-*-sunos3*
4383 Sun 3, running SunOS 4 m68*-*-sunos4*
4384 Sun 2, running SunOS 3 m68000-*-sunos3*
4385 Sun 2, running SunOS 4 m68000-*-sunos4*
4386 Motorola 680x0 running LynxOS m68*-*-lynxos*
4387 AT&T 3b1/Unix pc m68*-att-*
4388 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4389 decstation mips-dec-* mips-little-*
4390 riscos mips-*-riscos* mips-*-sysv*
4391 sonymips mips-sony-*
4392 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4394 * REMOVED configurations and files
4396 SGI Irix-4.x mips-sgi-irix4 or iris4
4397 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4398 Z8000 simulator z8k-zilog-none or z8ksim
4399 Matsushita MN10200 w/simulator mn10200-*-*
4400 H8/500 simulator h8500-hitachi-hms or h8500hms
4401 HP/PA running BSD hppa*-*-bsd*
4402 HP/PA running OSF/1 hppa*-*-osf*
4403 HP/PA Pro target hppa*-*-pro*
4404 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4405 386BSD i[3456]86-*-bsd*
4406 Sequent family i[3456]86-sequent-sysv4*
4407 i[3456]86-sequent-sysv*
4408 i[3456]86-sequent-bsd*
4409 SPARC running LynxOS sparc-*-lynxos*
4410 SPARC running SunOS 4 sparc-*-sunos4*
4411 Tsqware Sparclet sparclet-*-*
4412 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4414 *** Changes in GDB 6.0:
4418 Support for debugging the Objective-C programming language has been
4419 integrated into GDB.
4421 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4423 DWARF 2's Call Frame Information makes available compiler generated
4424 information that more exactly describes the program's run-time stack.
4425 By using this information, GDB is able to provide more robust stack
4428 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4429 have been updated to use a new backtrace mechanism which includes
4430 DWARF 2 CFI support.
4434 GDB's remote protocol has been extended to include support for hosted
4435 file I/O (where the remote target uses GDB's file system). See GDB's
4436 remote protocol documentation for details.
4438 * All targets using the new architecture framework.
4440 All of GDB's targets have been updated to use the new internal
4441 architecture framework. The way is now open for future GDB releases
4442 to include cross-architecture native debugging support (i386 on amd64,
4445 * GNU/Linux's Thread Local Storage (TLS)
4447 GDB now includes support for for the GNU/Linux implementation of
4448 per-thread variables.
4450 * GNU/Linux's Native POSIX Thread Library (NPTL)
4452 GDB's thread code has been updated to work with either the new
4453 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4455 * Separate debug info.
4457 GDB, in conjunction with BINUTILS, now supports a mechanism for
4458 automatically loading debug information from a separate file. Instead
4459 of shipping full debug and non-debug versions of system libraries,
4460 system integrators can now instead ship just the stripped libraries
4461 and optional debug files.
4463 * DWARF 2 Location Expressions
4465 DWARF 2 Location Expressions allow the compiler to more completely
4466 describe the location of variables (even in optimized code) to the
4469 GDB now includes preliminary support for location expressions (support
4470 for DW_OP_piece is still missing).
4474 A number of long standing bugs that caused GDB to die while starting a
4475 Java application have been fixed. GDB's Java support is now
4476 considered "useable".
4478 * GNU/Linux support for fork, vfork, and exec.
4480 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4481 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4484 * GDB supports logging output to a file
4486 There are two new commands, "set logging" and "show logging", which can be
4487 used to capture GDB's output to a file.
4489 * The meaning of "detach" has changed for gdbserver
4491 The "detach" command will now resume the application, as documented. To
4492 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4495 * d10v, m68hc11 `regs' command deprecated
4497 The `info registers' command has been updated so that it displays the
4498 registers using a format identical to the old `regs' command.
4502 A new command, "maint set profile on/off", has been added. This command can
4503 be used to enable or disable profiling while running GDB, to profile a
4504 session or a set of commands. In addition there is a new configure switch,
4505 "--enable-profiling", which will cause GDB to be compiled with profiling
4506 data, for more informative profiling results.
4508 * Default MI syntax changed to "mi2".
4510 The default MI (machine interface) syntax, enabled by the command line
4511 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4512 "mi1", can be enabled by specifying the option "-i=mi1".
4514 Support for the original "mi0" syntax (included in GDB 5.0) has been
4517 Fix for gdb/192: removed extraneous space when displaying frame level.
4518 Fix for gdb/672: update changelist is now output in mi list format.
4519 Fix for gdb/702: a -var-assign that updates the value now shows up
4520 in a subsequent -var-update.
4522 * New native configurations.
4524 FreeBSD/amd64 x86_64-*-freebsd*
4526 * Multi-arched targets.
4528 HP/PA HPUX11 hppa*-*-hpux*
4529 Renesas M32R/D w/simulator m32r-*-elf*
4531 * OBSOLETE configurations and files
4533 Configurations that have been declared obsolete in this release have
4534 been commented out. Unless there is activity to revive these
4535 configurations, the next release of GDB will have their sources
4536 permanently REMOVED.
4538 Z8000 simulator z8k-zilog-none or z8ksim
4539 Matsushita MN10200 w/simulator mn10200-*-*
4540 H8/500 simulator h8500-hitachi-hms or h8500hms
4541 HP/PA running BSD hppa*-*-bsd*
4542 HP/PA running OSF/1 hppa*-*-osf*
4543 HP/PA Pro target hppa*-*-pro*
4544 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4545 Sequent family i[3456]86-sequent-sysv4*
4546 i[3456]86-sequent-sysv*
4547 i[3456]86-sequent-bsd*
4548 Tsqware Sparclet sparclet-*-*
4549 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4551 * REMOVED configurations and files
4554 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4555 IBM AIX PS/2 i[3456]86-*-aix
4556 i386 running Mach 3.0 i[3456]86-*-mach3*
4557 i386 running Mach i[3456]86-*-mach*
4558 i386 running OSF/1 i[3456]86-*osf1mk*
4559 HP/Apollo 68k Family m68*-apollo*-sysv*,
4561 m68*-hp-bsd*, m68*-hp-hpux*
4562 Argonaut Risc Chip (ARC) arc-*-*
4563 Mitsubishi D30V d30v-*-*
4564 Fujitsu FR30 fr30-*-elf*
4565 OS/9000 i[34]86-*-os9k
4566 I960 with MON960 i960-*-coff
4568 * MIPS $fp behavior changed
4570 The convenience variable $fp, for the MIPS, now consistently returns
4571 the address of the current frame's base. Previously, depending on the
4572 context, $fp could refer to either $sp or the current frame's base
4573 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4574 The GNU Source-Level Debugger''.
4576 *** Changes in GDB 5.3:
4578 * GNU/Linux shared library multi-threaded performance improved.
4580 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4581 `/proc', in preference to `ptrace' for memory reads. This may result
4582 in an improvement in the start-up time of multi-threaded, shared
4583 library applications when run under GDB. One GDB user writes: ``loads
4584 shared libs like mad''.
4586 * ``gdbserver'' now supports multi-threaded applications on some targets
4588 Support for debugging multi-threaded applications which use
4589 the GNU/Linux LinuxThreads package has been added for
4590 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4591 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4593 * GDB now supports C/C++ preprocessor macros.
4595 GDB now expands preprocessor macro invocations in C/C++ expressions,
4596 and provides various commands for showing macro definitions and how
4599 The new command `macro expand EXPRESSION' expands any macro
4600 invocations in expression, and shows the result.
4602 The new command `show macro MACRO-NAME' shows the definition of the
4603 macro named MACRO-NAME, and where it was defined.
4605 Most compilers don't include information about macros in the debugging
4606 information by default. In GCC 3.1, for example, you need to compile
4607 your program with the options `-gdwarf-2 -g3'. If the macro
4608 information is present in the executable, GDB will read it.
4610 * Multi-arched targets.
4612 DEC Alpha (partial) alpha*-*-*
4613 DEC VAX (partial) vax-*-*
4615 National Semiconductor NS32000 (partial) ns32k-*-*
4616 Motorola 68000 (partial) m68k-*-*
4617 Motorola MCORE mcore-*-*
4621 Fujitsu FRV architecture added by Red Hat frv*-*-*
4624 * New native configurations
4626 Alpha NetBSD alpha*-*-netbsd*
4627 SH NetBSD sh*-*-netbsdelf*
4628 MIPS NetBSD mips*-*-netbsd*
4629 UltraSPARC NetBSD sparc64-*-netbsd*
4631 * OBSOLETE configurations and files
4633 Configurations that have been declared obsolete in this release have
4634 been commented out. Unless there is activity to revive these
4635 configurations, the next release of GDB will have their sources
4636 permanently REMOVED.
4638 Mitsubishi D30V d30v-*-*
4639 OS/9000 i[34]86-*-os9k
4640 IBM AIX PS/2 i[3456]86-*-aix
4641 Fujitsu FR30 fr30-*-elf*
4642 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4643 Argonaut Risc Chip (ARC) arc-*-*
4644 i386 running Mach 3.0 i[3456]86-*-mach3*
4645 i386 running Mach i[3456]86-*-mach*
4646 i386 running OSF/1 i[3456]86-*osf1mk*
4647 HP/Apollo 68k Family m68*-apollo*-sysv*,
4649 m68*-hp-bsd*, m68*-hp-hpux*
4650 I960 with MON960 i960-*-coff
4652 * OBSOLETE languages
4654 CHILL, a Pascal like language used by telecommunications companies.
4656 * REMOVED configurations and files
4658 AMD 29k family via UDI a29k-amd-udi, udi29k
4659 A29K VxWorks a29k-*-vxworks
4660 AMD 29000 embedded, using EBMON a29k-none-none
4661 AMD 29000 embedded with COFF a29k-none-coff
4662 AMD 29000 embedded with a.out a29k-none-aout
4664 testsuite/gdb.hp/gdb.threads-hp/ directory
4666 * New command "set max-user-call-depth <nnn>"
4668 This command allows the user to limit the call depth of user-defined
4669 commands. The default is 1024.
4671 * Changes in FreeBSD/i386 native debugging.
4673 Support for the "generate-core-file" has been added.
4675 * New commands "dump", "append", and "restore".
4677 These commands allow data to be copied from target memory
4678 to a bfd-format or binary file (dump and append), and back
4679 from a file into memory (restore).
4681 * Improved "next/step" support on multi-processor Alpha Tru64.
4683 The previous single-step mechanism could cause unpredictable problems,
4684 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4685 of a software single-step mechanism prevents this.
4687 *** Changes in GDB 5.2.1:
4695 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4696 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4697 Fix, by Joel Brobecker imported from mainline.
4699 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4700 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4701 Fix, by Fred Fish, imported from mainline.
4703 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4704 Surprisingly enough, it works now.
4705 By Michal Ludvig, imported from mainline.
4707 i386 hardware watchpoint support:
4708 avoid misses on second run for some targets.
4709 By Pierre Muller, imported from mainline.
4711 *** Changes in GDB 5.2:
4713 * New command "set trust-readonly-sections on[off]".
4715 This command is a hint that tells gdb that read-only sections
4716 really are read-only (ie. that their contents will not change).
4717 In this mode, gdb will go to the object file rather than the
4718 target to read memory from read-only sections (such as ".text").
4719 This can be a significant performance improvement on some
4720 (notably embedded) targets.
4722 * New command "generate-core-file" (or "gcore").
4724 This new gdb command allows the user to drop a core file of the child
4725 process state at any time. So far it's been implemented only for
4726 GNU/Linux and Solaris, but should be relatively easily ported to other
4727 hosts. Argument is core file name (defaults to core.<pid>).
4729 * New command line option
4731 GDB now accepts --pid or -p followed by a process id.
4733 * Change in command line behavior -- corefiles vs. process ids.
4735 There is a subtle behavior in the way in which GDB handles
4736 command line arguments. The first non-flag argument is always
4737 a program to debug, but the second non-flag argument may either
4738 be a corefile or a process id. Previously, GDB would attempt to
4739 open the second argument as a corefile, and if that failed, would
4740 issue a superfluous error message and then attempt to attach it as
4741 a process. Now, if the second argument begins with a non-digit,
4742 it will be treated as a corefile. If it begins with a digit,
4743 GDB will attempt to attach it as a process, and if no such process
4744 is found, will then attempt to open it as a corefile.
4746 * Changes in ARM configurations.
4748 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4749 configuration is fully multi-arch.
4751 * New native configurations
4753 ARM NetBSD arm*-*-netbsd*
4754 x86 OpenBSD i[3456]86-*-openbsd*
4755 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4756 Sparc64 running FreeBSD sparc64-*-freebsd*
4760 Sanyo XStormy16 xstormy16-elf
4762 * OBSOLETE configurations and files
4764 Configurations that have been declared obsolete in this release have
4765 been commented out. Unless there is activity to revive these
4766 configurations, the next release of GDB will have their sources
4767 permanently REMOVED.
4769 AMD 29k family via UDI a29k-amd-udi, udi29k
4770 A29K VxWorks a29k-*-vxworks
4771 AMD 29000 embedded, using EBMON a29k-none-none
4772 AMD 29000 embedded with COFF a29k-none-coff
4773 AMD 29000 embedded with a.out a29k-none-aout
4775 testsuite/gdb.hp/gdb.threads-hp/ directory
4777 * REMOVED configurations and files
4779 TI TMS320C80 tic80-*-*
4781 PowerPC Solaris powerpcle-*-solaris*
4782 PowerPC Windows NT powerpcle-*-cygwin32
4783 PowerPC Netware powerpc-*-netware*
4784 Harris/CXUX m88k m88*-harris-cxux*
4785 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4786 ns32k-utek-sysv* ns32k-utek-*
4787 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4788 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4789 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4790 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4791 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4793 * Changes to command line processing
4795 The new `--args' feature can be used to specify command-line arguments
4796 for the inferior from gdb's command line.
4798 * Changes to key bindings
4800 There is a new `operate-and-get-next' function bound to `C-o'.
4802 *** Changes in GDB 5.1.1
4804 Fix compile problem on DJGPP.
4806 Fix a problem with floating-point registers on the i386 being
4809 Fix to stop GDB crashing on .debug_str debug info.
4811 Numerous documentation fixes.
4813 Numerous testsuite fixes.
4815 *** Changes in GDB 5.1:
4817 * New native configurations
4819 Alpha FreeBSD alpha*-*-freebsd*
4820 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4821 MIPS GNU/Linux mips*-*-linux*
4822 MIPS SGI Irix 6.x mips*-sgi-irix6*
4823 ia64 AIX ia64-*-aix*
4824 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4828 Motorola 68HC11 and 68HC12 m68hc11-elf
4830 UltraSparc running GNU/Linux sparc64-*-linux*
4832 * OBSOLETE configurations and files
4834 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4835 Harris/CXUX m88k m88*-harris-cxux*
4836 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4837 ns32k-utek-sysv* ns32k-utek-*
4838 TI TMS320C80 tic80-*-*
4840 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4841 PowerPC Solaris powerpcle-*-solaris*
4842 PowerPC Windows NT powerpcle-*-cygwin32
4843 PowerPC Netware powerpc-*-netware*
4844 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4845 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4846 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4847 Apple Macintosh (MPW) host N/A
4849 stuff.c (Program to stuff files into a specially prepared space in kdb)
4850 kdb-start.c (Main loop for the standalone kernel debugger)
4852 Configurations that have been declared obsolete in this release have
4853 been commented out. Unless there is activity to revive these
4854 configurations, the next release of GDB will have their sources
4855 permanently REMOVED.
4857 * REMOVED configurations and files
4859 Altos 3068 m68*-altos-*
4860 Convex c1-*-*, c2-*-*
4862 ARM RISCix arm-*-* (as host)
4866 * GDB has been converted to ISO C.
4868 GDB's source code has been converted to ISO C. In particular, the
4869 sources are fully protoized, and rely on standard headers being
4874 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4876 * The MI enabled by default.
4878 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4879 revised and enabled by default. Packages which use GDB as a debugging
4880 engine behind a UI or another front end are encouraged to switch to
4881 using the GDB/MI interface, instead of the old annotations interface
4882 which is now deprecated.
4884 * Support for debugging Pascal programs.
4886 GDB now includes support for debugging Pascal programs. The following
4887 main features are supported:
4889 - Pascal-specific data types such as sets;
4891 - automatic recognition of Pascal sources based on file-name
4894 - Pascal-style display of data types, variables, and functions;
4896 - a Pascal expression parser.
4898 However, some important features are not yet supported.
4900 - Pascal string operations are not supported at all;
4902 - there are some problems with boolean types;
4904 - Pascal type hexadecimal constants are not supported
4905 because they conflict with the internal variables format;
4907 - support for Pascal objects and classes is not full yet;
4909 - unlike Pascal, GDB is case-sensitive for symbol names.
4911 * Changes in completion.
4913 Commands such as `shell', `run' and `set args', which pass arguments
4914 to inferior programs, now complete on file names, similar to what
4915 users expect at the shell prompt.
4917 Commands which accept locations, such as `disassemble', `print',
4918 `breakpoint', `until', etc. now complete on filenames as well as
4919 program symbols. Thus, if you type "break foob TAB", and the source
4920 files linked into the programs include `foobar.c', that file name will
4921 be one of the candidates for completion. However, file names are not
4922 considered for completion after you typed a colon that delimits a file
4923 name from a name of a function in that file, as in "break foo.c:bar".
4925 `set demangle-style' completes on available demangling styles.
4927 * New platform-independent commands:
4929 It is now possible to define a post-hook for a command as well as a
4930 hook that runs before the command. For more details, see the
4931 documentation of `hookpost' in the GDB manual.
4933 * Changes in GNU/Linux native debugging.
4935 Support for debugging multi-threaded programs has been completely
4936 revised for all platforms except m68k and sparc. You can now debug as
4937 many threads as your system allows you to have.
4939 Attach/detach is supported for multi-threaded programs.
4941 Support for SSE registers was added for x86. This doesn't work for
4942 multi-threaded programs though.
4944 * Changes in MIPS configurations.
4946 Multi-arch support is enabled for all MIPS configurations.
4948 GDB can now be built as native debugger on SGI Irix 6.x systems for
4949 debugging n32 executables. (Debugging 64-bit executables is not yet
4952 * Unified support for hardware watchpoints in all x86 configurations.
4954 Most (if not all) native x86 configurations support hardware-assisted
4955 breakpoints and watchpoints in a unified manner. This support
4956 implements debug register sharing between watchpoints, which allows to
4957 put a virtually infinite number of watchpoints on the same address,
4958 and also supports watching regions up to 16 bytes with several debug
4961 The new maintenance command `maintenance show-debug-regs' toggles
4962 debugging print-outs in functions that insert, remove, and test
4963 watchpoints and hardware breakpoints.
4965 * Changes in the DJGPP native configuration.
4967 New command ``info dos sysinfo'' displays assorted information about
4968 the CPU, OS, memory, and DPMI server.
4970 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4971 display information about segment descriptors stored in GDT, LDT, and
4974 New commands ``info dos pde'' and ``info dos pte'' display entries
4975 from Page Directory and Page Tables (for now works with CWSDPMI only).
4976 New command ``info dos address-pte'' displays the Page Table entry for
4977 a given linear address.
4979 GDB can now pass command lines longer than 126 characters to the
4980 program being debugged (requires an update to the libdbg.a library
4981 which is part of the DJGPP development kit).
4983 DWARF2 debug info is now supported.
4985 It is now possible to `step' and `next' through calls to `longjmp'.
4987 * Changes in documentation.
4989 All GDB documentation was converted to GFDL, the GNU Free
4990 Documentation License.
4992 Tracepoints-related commands are now fully documented in the GDB
4995 TUI, the Text-mode User Interface, is now documented in the manual.
4997 Tracepoints-related commands are now fully documented in the GDB
5000 The "GDB Internals" manual now has an index. It also includes
5001 documentation of `ui_out' functions, GDB coding standards, x86
5002 hardware watchpoints, and memory region attributes.
5004 * GDB's version number moved to ``version.in''
5006 The Makefile variable VERSION has been replaced by the file
5007 ``version.in''. People creating GDB distributions should update the
5008 contents of this file.
5012 GUD support is now a standard part of the EMACS distribution.
5014 *** Changes in GDB 5.0:
5016 * Improved support for debugging FP programs on x86 targets
5018 Unified and much-improved support for debugging floating-point
5019 programs on all x86 targets. In particular, ``info float'' now
5020 displays the FP registers in the same format on all x86 targets, with
5021 greater level of detail.
5023 * Improvements and bugfixes in hardware-assisted watchpoints
5025 It is now possible to watch array elements, struct members, and
5026 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5027 on x86 targets no longer erroneously trigger when the address is
5030 * Improvements in the native DJGPP version of GDB
5032 The distribution now includes all the scripts and auxiliary files
5033 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5034 machines ``out of the box''.
5036 The DJGPP version can now debug programs that use signals. It is
5037 possible to catch signals that happened in the debuggee, deliver
5038 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5039 would kill the program being debugged.) Programs that hook hardware
5040 interrupts (keyboard, timer, etc.) can also be debugged.
5042 It is now possible to debug DJGPP programs that redirect their
5043 standard handles or switch them to raw (as opposed to cooked) mode, or
5044 even close them. The command ``run < foo > bar'' works as expected,
5045 and ``info terminal'' reports useful information about the debuggee's
5046 terminal, including raw/cooked mode, redirection, etc.
5048 The DJGPP version now uses termios functions for console I/O, which
5049 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5052 DOS-style file names with drive letters are now fully supported by
5055 It is now possible to debug DJGPP programs that switch their working
5056 directory. It is also possible to rerun the debuggee any number of
5057 times without restarting GDB; thus, you can use the same setup,
5058 breakpoints, etc. for many debugging sessions.
5060 * New native configurations
5062 ARM GNU/Linux arm*-*-linux*
5063 PowerPC GNU/Linux powerpc-*-linux*
5067 Motorola MCore mcore-*-*
5068 x86 VxWorks i[3456]86-*-vxworks*
5069 PowerPC VxWorks powerpc-*-vxworks*
5070 TI TMS320C80 tic80-*-*
5072 * OBSOLETE configurations
5074 Altos 3068 m68*-altos-*
5075 Convex c1-*-*, c2-*-*
5077 ARM RISCix arm-*-* (as host)
5080 Configurations that have been declared obsolete will be commented out,
5081 but the code will be left in place. If there is no activity to revive
5082 these configurations before the next release of GDB, the sources will
5083 be permanently REMOVED.
5085 * Gould support removed
5087 Support for the Gould PowerNode and NP1 has been removed.
5089 * New features for SVR4
5091 On SVR4 native platforms (such as Solaris), if you attach to a process
5092 without first loading a symbol file, GDB will now attempt to locate and
5093 load symbols from the running process's executable file.
5095 * Many C++ enhancements
5097 C++ support has been greatly improved. Overload resolution now works properly
5098 in almost all cases. RTTI support is on the way.
5100 * Remote targets can connect to a sub-program
5102 A popen(3) style serial-device has been added. This device starts a
5103 sub-process (such as a stand-alone simulator) and then communicates
5104 with that. The sub-program to run is specified using the syntax
5105 ``|<program> <args>'' vis:
5107 (gdb) set remotedebug 1
5108 (gdb) target extended-remote |mn10300-elf-sim program-args
5110 * MIPS 64 remote protocol
5112 A long standing bug in the mips64 remote protocol where by GDB
5113 expected certain 32 bit registers (ex SR) to be transfered as 32
5114 instead of 64 bits has been fixed.
5116 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5117 added to provide backward compatibility with older versions of GDB.
5119 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5121 The command ``set remotebinarydownload'' command has been replaced by
5122 ``set remote X-packet''. Other commands in ``set remote'' family
5123 include ``set remote P-packet''.
5125 * Breakpoint commands accept ranges.
5127 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5128 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5129 ``tracepoint passcount'' also accepts a range of tracepoints.
5131 * ``apropos'' command added.
5133 The ``apropos'' command searches through command names and
5134 documentation strings, printing out matches, making it much easier to
5135 try to find a command that does what you are looking for.
5139 A new machine oriented interface (MI) has been added to GDB. This
5140 interface is designed for debug environments running GDB as a separate
5141 process. This is part of the long term libGDB project. See the
5142 "GDB/MI" chapter of the GDB manual for further information. It can be
5143 enabled by configuring with:
5145 .../configure --enable-gdbmi
5147 *** Changes in GDB-4.18:
5149 * New native configurations
5151 HP-UX 10.20 hppa*-*-hpux10.20
5152 HP-UX 11.x hppa*-*-hpux11.0*
5153 M68K GNU/Linux m68*-*-linux*
5157 Fujitsu FR30 fr30-*-elf*
5158 Intel StrongARM strongarm-*-*
5159 Mitsubishi D30V d30v-*-*
5161 * OBSOLETE configurations
5163 Gould PowerNode, NP1 np1-*-*, pn-*-*
5165 Configurations that have been declared obsolete will be commented out,
5166 but the code will be left in place. If there is no activity to revive
5167 these configurations before the next release of GDB, the sources will
5168 be permanently REMOVED.
5172 As a compatibility experiment, GDB's source files buildsym.h and
5173 buildsym.c have been converted to pure standard C, no longer
5174 containing any K&R compatibility code. We believe that all systems in
5175 use today either come with a standard C compiler, or have a GCC port
5176 available. If this is not true, please report the affected
5177 configuration to bug-gdb@gnu.org immediately. See the README file for
5178 information about getting a standard C compiler if you don't have one
5183 GDB now uses readline 2.2.
5185 * set extension-language
5187 You can now control the mapping between filename extensions and source
5188 languages by using the `set extension-language' command. For instance,
5189 you can ask GDB to treat .c files as C++ by saying
5190 set extension-language .c c++
5191 The command `info extensions' lists all of the recognized extensions
5192 and their associated languages.
5194 * Setting processor type for PowerPC and RS/6000
5196 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5197 you can use the `set processor' command to specify what variant of the
5198 PowerPC family you are debugging. The command
5202 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5203 following PowerPC and RS6000 variants:
5205 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5206 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5208 403GC IBM PowerPC 403GC
5209 505 Motorola PowerPC 505
5210 860 Motorola PowerPC 860 or 850
5211 601 Motorola PowerPC 601
5212 602 Motorola PowerPC 602
5213 603 Motorola/IBM PowerPC 603 or 603e
5214 604 Motorola PowerPC 604 or 604e
5215 750 Motorola/IBM PowerPC 750 or 750
5217 At the moment, this command just tells GDB what to name the
5218 special-purpose processor registers. Since almost all the affected
5219 registers are inaccessible to user-level programs, this command is
5220 only useful for remote debugging in its present form.
5224 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5225 more extensive support for HP-UX. Added features include shared
5226 library support, kernel threads and hardware watchpoints for 11.00,
5227 support for HP's ANSI C and C++ compilers, and a compatibility mode
5228 for xdb and dbx commands.
5232 HP's donation includes the new concept of catchpoints, which is a
5233 generalization of the old catch command. On HP-UX, it is now possible
5234 to catch exec, fork, and vfork, as well as library loading.
5236 This means that the existing catch command has changed; its first
5237 argument now specifies the type of catch to be set up. See the
5238 output of "help catch" for a list of catchpoint types.
5240 * Debugging across forks
5242 On HP-UX, you can choose which process to debug when a fork() happens
5247 HP has donated a curses-based terminal user interface (TUI). To get
5248 it, build with --enable-tui. Although this can be enabled for any
5249 configuration, at present it only works for native HP debugging.
5251 * GDB remote protocol additions
5253 A new protocol packet 'X' that writes binary data is now available.
5254 Default behavior is to try 'X', then drop back to 'M' if the stub
5255 fails to respond. The settable variable `remotebinarydownload'
5256 allows explicit control over the use of 'X'.
5258 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5259 full 64-bit address. The command
5261 set remoteaddresssize 32
5263 can be used to revert to the old behaviour. For existing remote stubs
5264 the change should not be noticed, as the additional address information
5267 In order to assist in debugging stubs, you may use the maintenance
5268 command `packet' to send any text string to the stub. For instance,
5270 maint packet heythere
5272 sends the packet "$heythere#<checksum>". Note that it is very easy to
5273 disrupt a debugging session by sending the wrong packet at the wrong
5276 The compare-sections command allows you to compare section data on the
5277 target to what is in the executable file without uploading or
5278 downloading, by comparing CRC checksums.
5280 * Tracing can collect general expressions
5282 You may now collect general expressions at tracepoints. This requires
5283 further additions to the target-side stub; see tracepoint.c and
5284 doc/agentexpr.texi for further details.
5286 * mask-address variable for Mips
5288 For Mips targets, you may control the zeroing of the upper 32 bits of
5289 a 64-bit address by entering `set mask-address on'. This is mainly
5290 of interest to users of embedded R4xxx and R5xxx processors.
5292 * Higher serial baud rates
5294 GDB's serial code now allows you to specify baud rates 57600, 115200,
5295 230400, and 460800 baud. (Note that your host system may not be able
5296 to achieve all of these rates.)
5300 The i960 configuration now includes an initial implementation of a
5301 builtin simulator, contributed by Jim Wilson.
5304 *** Changes in GDB-4.17:
5306 * New native configurations
5308 Alpha GNU/Linux alpha*-*-linux*
5309 Unixware 2.x i[3456]86-unixware2*
5310 Irix 6.x mips*-sgi-irix6*
5311 PowerPC GNU/Linux powerpc-*-linux*
5312 PowerPC Solaris powerpcle-*-solaris*
5313 Sparc GNU/Linux sparc-*-linux*
5314 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5318 Argonaut Risc Chip (ARC) arc-*-*
5319 Hitachi H8/300S h8300*-*-*
5320 Matsushita MN10200 w/simulator mn10200-*-*
5321 Matsushita MN10300 w/simulator mn10300-*-*
5322 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5323 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5324 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5325 Mitsubishi D10V w/simulator d10v-*-*
5326 Mitsubishi M32R/D w/simulator m32r-*-elf*
5327 Tsqware Sparclet sparclet-*-*
5328 NEC V850 w/simulator v850-*-*
5330 * New debugging protocols
5332 ARM with RDI protocol arm*-*-*
5333 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5334 DDB and LSI variants of PMON protocol mips*-*-*
5335 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5336 PowerPC with SDS protocol powerpc{,le}-*-eabi
5337 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5341 All configurations can now understand and use the DWARF 2 debugging
5342 format. The choice is automatic, if the symbol file contains DWARF 2
5347 GDB now includes basic Java language support. This support is
5348 only useful with Java compilers that produce native machine code.
5350 * solib-absolute-prefix and solib-search-path
5352 For SunOS and SVR4 shared libraries, you may now set the prefix for
5353 loading absolute shared library symbol files, and the search path for
5354 locating non-absolute shared library symbol files.
5356 * Live range splitting
5358 GDB can now effectively debug code for which GCC has performed live
5359 range splitting as part of its optimization. See gdb/doc/LRS for
5360 more details on the expected format of the stabs information.
5364 GDB's support for the GNU Hurd, including thread debugging, has been
5365 updated to work with current versions of the Hurd.
5369 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5370 instruction set. ARM GDB automatically detects when Thumb
5371 instructions are in use, and adjusts disassembly and backtracing
5376 GDB's MIPS target configurations now handle the MIP16 16-bit
5381 GDB now includes support for overlays; if an executable has been
5382 linked such that multiple sections are based at the same address, GDB
5383 will decide which section to use for symbolic info. You can choose to
5384 control the decision manually, using overlay commands, or implement
5385 additional target-side support and use "overlay load-target" to bring
5386 in the overlay mapping. Do "help overlay" for more detail.
5390 The command "info symbol <address>" displays information about
5391 the symbol at the specified address.
5395 The standard remote protocol now includes an extension that allows
5396 asynchronous collection and display of trace data. This requires
5397 extensive support in the target-side debugging stub. Tracing mode
5398 includes a new interaction mode in GDB and new commands: see the
5399 file tracepoint.c for more details.
5403 Configurations for embedded MIPS now include a simulator contributed
5404 by Cygnus Solutions. The simulator supports the instruction sets
5405 of most MIPS variants.
5409 Sparc configurations may now include the ERC32 simulator contributed
5410 by the European Space Agency. The simulator is not built into
5411 Sparc targets by default; configure with --enable-sim to include it.
5415 For target configurations that may include multiple variants of a
5416 basic architecture (such as MIPS and SH), you may now set the
5417 architecture explicitly. "set arch" sets, "info arch" lists
5418 the possible architectures.
5420 *** Changes in GDB-4.16:
5422 * New native configurations
5424 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5425 M68K NetBSD m68k-*-netbsd*
5426 PowerPC AIX 4.x powerpc-*-aix*
5427 PowerPC MacOS powerpc-*-macos*
5428 PowerPC Windows NT powerpcle-*-cygwin32
5429 RS/6000 AIX 4.x rs6000-*-aix4*
5433 ARM with RDP protocol arm-*-*
5434 I960 with MON960 i960-*-coff
5435 MIPS VxWorks mips*-*-vxworks*
5436 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5437 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5439 Matra Sparclet sparclet-*-*
5443 The powerpc-eabi configuration now includes the PSIM simulator,
5444 contributed by Andrew Cagney, with assistance from Mike Meissner.
5445 PSIM is a very elaborate model of the PowerPC, including not only
5446 basic instruction set execution, but also details of execution unit
5447 performance and I/O hardware. See sim/ppc/README for more details.
5451 GDB now works with Solaris 2.5.
5453 * Windows 95/NT native
5455 GDB will now work as a native debugger on Windows 95 and Windows NT.
5456 To build it from source, you must use the "gnu-win32" environment,
5457 which uses a DLL to emulate enough of Unix to run the GNU tools.
5458 Further information, binaries, and sources are available at
5459 ftp.cygnus.com, under pub/gnu-win32.
5461 * dont-repeat command
5463 If a user-defined command includes the command `dont-repeat', then the
5464 command will not be repeated if the user just types return. This is
5465 useful if the command is time-consuming to run, so that accidental
5466 extra keystrokes don't run the same command many times.
5468 * Send break instead of ^C
5470 The standard remote protocol now includes an option to send a break
5471 rather than a ^C to the target in order to interrupt it. By default,
5472 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5474 * Remote protocol timeout
5476 The standard remote protocol includes a new variable `remotetimeout'
5477 that allows you to set the number of seconds before GDB gives up trying
5478 to read from the target. The default value is 2.
5480 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5482 By default GDB will automatically keep track of objects as they are
5483 loaded and unloaded by the dynamic linker. By using the command `set
5484 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5485 when shared library events occur, thus allowing you to set breakpoints
5486 in shared libraries which are explicitly loaded by the inferior.
5488 Note this feature does not work on hpux8. On hpux9 you must link
5489 /usr/lib/end.o into your program. This feature should work
5490 automatically on hpux10.
5492 * Irix 5.x hardware watchpoint support
5494 Irix 5 configurations now support the use of hardware watchpoints.
5496 * Mips protocol "SYN garbage limit"
5498 When debugging a Mips target using the `target mips' protocol, you
5499 may set the number of characters that GDB will ignore by setting
5500 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5501 every character. The default value is 1050.
5503 * Recording and replaying remote debug sessions
5505 If you set `remotelogfile' to the name of a file, gdb will write to it
5506 a recording of a remote debug session. This recording may then be
5507 replayed back to gdb using "gdbreplay". See gdbserver/README for
5508 details. This is useful when you have a problem with GDB while doing
5509 remote debugging; you can make a recording of the session and send it
5510 to someone else, who can then recreate the problem.
5512 * Speedups for remote debugging
5514 GDB includes speedups for downloading and stepping MIPS systems using
5515 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5516 and more efficient S-record downloading.
5518 * Memory use reductions and statistics collection
5520 GDB now uses less memory and reports statistics about memory usage.
5521 Try the `maint print statistics' command, for example.
5523 *** Changes in GDB-4.15:
5525 * Psymtabs for XCOFF
5527 The symbol reader for AIX GDB now uses partial symbol tables. This
5528 can greatly improve startup time, especially for large executables.
5530 * Remote targets use caching
5532 Remote targets now use a data cache to speed up communication with the
5533 remote side. The data cache could lead to incorrect results because
5534 it doesn't know about volatile variables, thus making it impossible to
5535 debug targets which use memory mapped I/O devices. `set remotecache
5536 off' turns the the data cache off.
5538 * Remote targets may have threads
5540 The standard remote protocol now includes support for multiple threads
5541 in the target system, using new protocol commands 'H' and 'T'. See
5542 gdb/remote.c for details.
5546 If GDB is configured with `--enable-netrom', then it will include
5547 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5548 acts as though it is a bank of ROM on the target board, but you can
5549 write into it over the network. GDB's support consists only of
5550 support for fast loading into the emulated ROM; to debug, you must use
5551 another protocol, such as standard remote protocol. The usual
5552 sequence is something like
5554 target nrom <netrom-hostname>
5556 target remote <netrom-hostname>:1235
5560 GDB now includes support for the Apple Macintosh, as a host only. It
5561 may be run as either an MPW tool or as a standalone application, and
5562 it can debug through the serial port. All the usual GDB commands are
5563 available, but to the target command, you must supply "serial" as the
5564 device type instead of "/dev/ttyXX". See mpw-README in the main
5565 directory for more information on how to build. The MPW configuration
5566 scripts */mpw-config.in support only a few targets, and only the
5567 mips-idt-ecoff target has been tested.
5571 GDB configuration now uses autoconf. This is not user-visible,
5572 but does simplify configuration and building.
5576 GDB now supports hpux10.
5578 *** Changes in GDB-4.14:
5580 * New native configurations
5582 x86 FreeBSD i[345]86-*-freebsd
5583 x86 NetBSD i[345]86-*-netbsd
5584 NS32k NetBSD ns32k-*-netbsd
5585 Sparc NetBSD sparc-*-netbsd
5589 A29K VxWorks a29k-*-vxworks
5590 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5591 CPU32 EST-300 emulator m68*-*-est*
5592 PowerPC ELF powerpc-*-elf
5595 * Alpha OSF/1 support for procfs
5597 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5598 possible to attach to running processes. As the mounting of the /proc
5599 filesystem is optional on the Alpha, GDB automatically determines
5600 the availability of /proc during startup. This can lead to problems
5601 if /proc is unmounted after GDB has been started.
5603 * Arguments to user-defined commands
5605 User commands may accept up to 10 arguments separated by whitespace.
5606 Arguments are accessed within the user command via $arg0..$arg9. A
5609 print $arg0 + $arg1 + $arg2
5611 To execute the command use:
5614 Defines the command "adder" which prints the sum of its three arguments.
5615 Note the arguments are text substitutions, so they may reference variables,
5616 use complex expressions, or even perform inferior function calls.
5618 * New `if' and `while' commands
5620 This makes it possible to write more sophisticated user-defined
5621 commands. Both commands take a single argument, which is the
5622 expression to evaluate, and must be followed by the commands to
5623 execute, one per line, if the expression is nonzero, the list being
5624 terminated by the word `end'. The `if' command list may include an
5625 `else' word, which causes the following commands to be executed only
5626 if the expression is zero.
5628 * Fortran source language mode
5630 GDB now includes partial support for Fortran 77. It will recognize
5631 Fortran programs and can evaluate a subset of Fortran expressions, but
5632 variables and functions may not be handled correctly. GDB will work
5633 with G77, but does not yet know much about symbols emitted by other
5636 * Better HPUX support
5638 Most debugging facilities now work on dynamic executables for HPPAs
5639 running hpux9 or later. You can attach to running dynamically linked
5640 processes, but by default the dynamic libraries will be read-only, so
5641 for instance you won't be able to put breakpoints in them. To change
5642 that behavior do the following before running the program:
5648 This will cause the libraries to be mapped private and read-write.
5649 To revert to the normal behavior, do this:
5655 You cannot set breakpoints or examine data in the library until after
5656 the library is loaded if the function/data symbols do not have
5659 GDB can now also read debug symbols produced by the HP C compiler on
5660 HPPAs (sorry, no C++, Fortran or 68k support).
5662 * Target byte order now dynamically selectable
5664 You can choose which byte order to use with a target system, via the
5665 commands "set endian big" and "set endian little", and you can see the
5666 current setting by using "show endian". You can also give the command
5667 "set endian auto", in which case GDB will use the byte order
5668 associated with the executable. Currently, only embedded MIPS
5669 configurations support dynamic selection of target byte order.
5671 * New DOS host serial code
5673 This version uses DPMI interrupts to handle buffered I/O, so you
5674 no longer need to run asynctsr when debugging boards connected to
5677 *** Changes in GDB-4.13:
5679 * New "complete" command
5681 This lists all the possible completions for the rest of the line, if it
5682 were to be given as a command itself. This is intended for use by emacs.
5684 * Trailing space optional in prompt
5686 "set prompt" no longer adds a space for you after the prompt you set. This
5687 allows you to set a prompt which ends in a space or one that does not.
5689 * Breakpoint hit counts
5691 "info break" now displays a count of the number of times the breakpoint
5692 has been hit. This is especially useful in conjunction with "ignore"; you
5693 can ignore a large number of breakpoint hits, look at the breakpoint info
5694 to see how many times the breakpoint was hit, then run again, ignoring one
5695 less than that number, and this will get you quickly to the last hit of
5698 * Ability to stop printing at NULL character
5700 "set print null-stop" will cause GDB to stop printing the characters of
5701 an array when the first NULL is encountered. This is useful when large
5702 arrays actually contain only short strings.
5704 * Shared library breakpoints
5706 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5707 breakpoints in shared libraries before the executable is run.
5709 * Hardware watchpoints
5711 There is a new hardware breakpoint for the watch command for sparclite
5712 targets. See gdb/sparclite/hw_breakpoint.note.
5714 Hardware watchpoints are also now supported under GNU/Linux.
5718 Annotations have been added. These are for use with graphical interfaces,
5719 and are still experimental. Currently only gdba.el uses these.
5721 * Improved Irix 5 support
5723 GDB now works properly with Irix 5.2.
5725 * Improved HPPA support
5727 GDB now works properly with the latest GCC and GAS.
5729 * New native configurations
5731 Sequent PTX4 i[34]86-sequent-ptx4
5732 HPPA running OSF/1 hppa*-*-osf*
5733 Atari TT running SVR4 m68*-*-sysv4*
5734 RS/6000 LynxOS rs6000-*-lynxos*
5738 OS/9000 i[34]86-*-os9k
5739 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5742 * Hitachi SH7000 and E7000-PC ICE support
5744 There is now support for communicating with the Hitachi E7000-PC ICE.
5745 This is available automatically when GDB is configured for the SH.
5749 As usual, a variety of small fixes and improvements, both generic
5750 and configuration-specific. See the ChangeLog for more detail.
5752 *** Changes in GDB-4.12:
5754 * Irix 5 is now supported
5758 GDB-4.12 on the HPPA has a number of changes which make it unable
5759 to debug the output from the currently released versions of GCC and
5760 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5761 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5762 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5765 *** Changes in GDB-4.11:
5767 * User visible changes:
5771 The "set remotedebug" option is now consistent between the mips remote
5772 target, remote targets using the gdb-specific protocol, UDI (AMD's
5773 debug protocol for the 29k) and the 88k bug monitor. It is now an
5774 integer specifying a debug level (normally 0 or 1, but 2 means more
5775 debugging info for the mips target).
5777 * DEC Alpha native support
5779 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5780 debug info, but GDB works fairly well with the DEC compiler and should
5781 work with a future GCC release. See the README file for a few
5782 Alpha-specific notes.
5784 * Preliminary thread implementation
5786 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5788 * LynxOS native and target support for 386
5790 This release has been hosted on LynxOS 2.2, and also can be configured
5791 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5794 * Improvements in C++ mangling/demangling.
5796 This release has much better g++ debugging, specifically in name
5797 mangling/demangling, virtual function calls, print virtual table,
5798 call methods, ...etc.
5800 *** Changes in GDB-4.10:
5802 * User visible changes:
5804 Remote debugging using the GDB-specific (`target remote') protocol now
5805 supports the `load' command. This is only useful if you have some
5806 other way of getting the stub to the target system, and you can put it
5807 somewhere in memory where it won't get clobbered by the download.
5809 Filename completion now works.
5811 When run under emacs mode, the "info line" command now causes the
5812 arrow to point to the line specified. Also, "info line" prints
5813 addresses in symbolic form (as well as hex).
5815 All vxworks based targets now support a user settable option, called
5816 vxworks-timeout. This option represents the number of seconds gdb
5817 should wait for responses to rpc's. You might want to use this if
5818 your vxworks target is, perhaps, a slow software simulator or happens
5819 to be on the far side of a thin network line.
5823 This release contains support for using a DEC alpha as a GDB host for
5824 cross debugging. Native alpha debugging is not supported yet.
5827 *** Changes in GDB-4.9:
5831 This is the first GDB release which is accompanied by a matching testsuite.
5832 The testsuite requires installation of dejagnu, which should be available
5833 via ftp from most sites that carry GNU software.
5837 'Cfront' style demangling has had its name changed to 'ARM' style, to
5838 emphasize that it was written from the specifications in the C++ Annotated
5839 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5840 disclaimers, it still generated too much confusion with users attempting to
5841 use gdb with AT&T cfront.
5845 GDB now uses a standard remote interface to a simulator library.
5846 So far, the library contains simulators for the Zilog Z8001/2, the
5847 Hitachi H8/300, H8/500 and Super-H.
5849 * New targets supported
5851 H8/300 simulator h8300-hitachi-hms or h8300hms
5852 H8/500 simulator h8500-hitachi-hms or h8500hms
5853 SH simulator sh-hitachi-hms or sh
5854 Z8000 simulator z8k-zilog-none or z8ksim
5855 IDT MIPS board over serial line mips-idt-ecoff
5857 Cross-debugging to GO32 targets is supported. It requires a custom
5858 version of the i386-stub.c module which is integrated with the
5859 GO32 memory extender.
5861 * New remote protocols
5863 MIPS remote debugging protocol.
5865 * New source languages supported
5867 This version includes preliminary support for Chill, a Pascal like language
5868 used by telecommunications companies. Chill support is also being integrated
5869 into the GNU compiler, but we don't know when it will be publically available.
5872 *** Changes in GDB-4.8:
5874 * HP Precision Architecture supported
5876 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5877 version of this support was available as a set of patches from the
5878 University of Utah. GDB does not support debugging of programs
5879 compiled with the HP compiler, because HP will not document their file
5880 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5881 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5883 Many problems in the preliminary version have been fixed.
5885 * Faster and better demangling
5887 We have improved template demangling and fixed numerous bugs in the GNU style
5888 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5889 character types (wchar_t) are now supported. Demangling of each symbol is now
5890 only done once, and is cached when the symbol table for a file is read in.
5891 This results in a small increase in memory usage for C programs, a moderate
5892 increase in memory usage for C++ programs, and a fantastic speedup in
5895 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5896 from the specifications in the Annotated Reference Manual, which AT&T's
5897 compiler does not actually implement.
5899 * G++ multiple inheritance compiler problem
5901 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5902 inheritance lattices was reworked to properly discover ambiguities. We
5903 recently found an example which causes this new algorithm to fail in a
5904 very subtle way, producing bad debug information for those classes.
5905 The file 'gcc.patch' (in this directory) can be applied to gcc to
5906 circumvent the problem. A future GCC release will contain a complete
5909 The previous G++ debug info problem (mentioned below for the gdb-4.7
5910 release) is fixed in gcc version 2.3.2.
5912 * Improved configure script
5914 The `configure' script will now attempt to guess your system type if
5915 you don't supply a host system type. The old scheme of supplying a
5916 host system triplet is preferable over using this. All the magic is
5917 done in the new `config.guess' script. Examine it for details.
5919 We have also brought our configure script much more in line with the FSF's
5920 version. It now supports the --with-xxx options. In particular,
5921 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5922 The resulting GDB will not be able to read arbitrary object file formats --
5923 only the format ``expected'' to be used on the configured target system.
5924 We hope to make this the default in a future release.
5926 * Documentation improvements
5928 There's new internal documentation on how to modify GDB, and how to
5929 produce clean changes to the code. We implore people to read it
5930 before submitting changes.
5932 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5933 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5934 `info' files are also provided. To build `info' files from scratch,
5935 you will need the latest `makeinfo' release, which will be available in
5936 a future texinfo-X.Y release.
5938 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5939 We're not sure exactly which versions have this problem, but it has
5940 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5941 or better. If that isn't possible, there is a patch in
5942 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5943 around this problem.
5947 GDB now supports array constants that can be used in expressions typed in by
5948 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5949 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5952 The new directory `gdb/sparclite' contains a program that demonstrates
5953 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5955 * New native hosts supported
5957 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5958 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5960 * New targets supported
5962 AMD 29k family via UDI a29k-amd-udi or udi29k
5964 * New file formats supported
5966 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5967 HPUX core files, and SCO 3.2v2 core files.
5971 Attaching to processes now works again; thanks for the many bug reports.
5973 We have also stomped on a bunch of core dumps caused by
5974 printf_filtered("%s") problems.
5976 We eliminated a copyright problem on the rpc and ptrace header files
5977 for VxWorks, which was discovered at the last minute during the 4.7
5978 release. You should now be able to build a VxWorks GDB.
5980 You can now interrupt gdb while an attached process is running. This
5981 will cause the attached process to stop, and give control back to GDB.
5983 We fixed problems caused by using too many file descriptors
5984 for reading symbols from object files and libraries. This was
5985 especially a problem for programs that used many (~100) shared
5988 The `step' command now only enters a subroutine if there is line number
5989 information for the subroutine. Otherwise it acts like the `next'
5990 command. Previously, `step' would enter subroutines if there was
5991 any debugging information about the routine. This avoids problems
5992 when using `cc -g1' on MIPS machines.
5994 * Internal improvements
5996 GDB's internal interfaces have been improved to make it easier to support
5997 debugging of multiple languages in the future.
5999 GDB now uses a common structure for symbol information internally.
6000 Minimal symbols (derived from linkage symbols in object files), partial
6001 symbols (from a quick scan of debug information), and full symbols
6002 contain a common subset of information, making it easier to write
6003 shared code that handles any of them.
6005 * New command line options
6007 We now accept --silent as an alias for --quiet.
6011 The memory-mapped-malloc library is now licensed under the GNU Library
6012 General Public License.
6014 *** Changes in GDB-4.7:
6016 * Host/native/target split
6018 GDB has had some major internal surgery to untangle the support for
6019 hosts and remote targets. Now, when you configure GDB for a remote
6020 target, it will no longer load in all of the support for debugging
6021 local programs on the host. When fully completed and tested, this will
6022 ensure that arbitrary host/target combinations are possible.
6024 The primary conceptual shift is to separate the non-portable code in
6025 GDB into three categories. Host specific code is required any time GDB
6026 is compiled on that host, regardless of the target. Target specific
6027 code relates to the peculiarities of the target, but can be compiled on
6028 any host. Native specific code is everything else: it can only be
6029 built when the host and target are the same system. Child process
6030 handling and core file support are two common `native' examples.
6032 GDB's use of /proc for controlling Unix child processes is now cleaner.
6033 It has been split out into a single module under the `target_ops' vector,
6034 plus two native-dependent functions for each system that uses /proc.
6036 * New hosts supported
6038 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6039 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6040 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6042 * New targets supported
6044 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6045 68030 and CPU32 m68030-*-*, m68332-*-*
6047 * New native hosts supported
6049 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6050 (386bsd is not well tested yet)
6051 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6053 * New file formats supported
6055 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6056 supports reading of `a.out.adobe' object files, which are an a.out
6057 format extended with minimal information about multiple sections.
6061 `show copying' is the same as the old `info copying'.
6062 `show warranty' is the same as `info warrantee'.
6063 These were renamed for consistency. The old commands continue to work.
6065 `info handle' is a new alias for `info signals'.
6067 You can now define pre-command hooks, which attach arbitrary command
6068 scripts to any command. The commands in the hook will be executed
6069 prior to the user's command. You can also create a hook which will be
6070 executed whenever the program stops. See gdb.texinfo.
6074 We now deal with Cfront style name mangling, and can even extract type
6075 info from mangled symbols. GDB can automatically figure out which
6076 symbol mangling style your C++ compiler uses.
6078 Calling of methods and virtual functions has been improved as well.
6082 The crash that occured when debugging Sun Ansi-C compiled binaries is
6083 fixed. This was due to mishandling of the extra N_SO stabs output
6086 We also finally got Ultrix 4.2 running in house, and fixed core file
6087 support, with help from a dozen people on the net.
6089 John M. Farrell discovered that the reason that single-stepping was so
6090 slow on all of the Mips based platforms (primarily SGI and DEC) was
6091 that we were trying to demangle and lookup a symbol used for internal
6092 purposes on every instruction that was being stepped through. Changing
6093 the name of that symbol so that it couldn't be mistaken for a C++
6094 mangled symbol sped things up a great deal.
6096 Rich Pixley sped up symbol lookups in general by getting much smarter
6097 about when C++ symbol mangling is necessary. This should make symbol
6098 completion (TAB on the command line) much faster. It's not as fast as
6099 we'd like, but it's significantly faster than gdb-4.6.
6103 A new user controllable variable 'call_scratch_address' can
6104 specify the location of a scratch area to be used when GDB
6105 calls a function in the target. This is necessary because the
6106 usual method of putting the scratch area on the stack does not work
6107 in systems that have separate instruction and data spaces.
6109 We integrated changes to support the 29k UDI (Universal Debugger
6110 Interface), but discovered at the last minute that we didn't have all
6111 of the appropriate copyright paperwork. We are working with AMD to
6112 resolve this, and hope to have it available soon.
6116 We have sped up the remote serial line protocol, especially for targets
6117 with lots of registers. It now supports a new `expedited status' ('T')
6118 message which can be used in place of the existing 'S' status message.
6119 This allows the remote stub to send only the registers that GDB
6120 needs to make a quick decision about single-stepping or conditional
6121 breakpoints, eliminating the need to fetch the entire register set for
6122 each instruction being stepped through.
6124 The GDB remote serial protocol now implements a write-through cache for
6125 registers, only re-reading the registers if the target has run.
6127 There is also a new remote serial stub for SPARC processors. You can
6128 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6129 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6130 processor with a serial port.
6134 Configure.in files have become much easier to read and modify. A new
6135 `table driven' format makes it more obvious what configurations are
6136 supported, and what files each one uses.
6140 There is a new opcodes library which will eventually contain all of the
6141 disassembly routines and opcode tables. At present, it only contains
6142 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6143 disassembler (binutils/objdump) to share these routines.
6145 The libiberty library is now copylefted under the GNU Library General
6146 Public License. This allows more liberal use, and was done so libg++
6147 can use it. This makes no difference to GDB, since the Library License
6148 grants all the rights from the General Public License.
6152 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6153 reference to the stabs symbol info used by the debugger. It is (as far
6154 as we know) the only published document on this fascinating topic. We
6155 encourage you to read it, compare it to the stabs information on your
6156 system, and send improvements on the document in general (to
6157 bug-gdb@prep.ai.mit.edu).
6159 And, of course, many bugs have been fixed.
6162 *** Changes in GDB-4.6:
6164 * Better support for C++ function names
6166 GDB now accepts as input the "demangled form" of C++ overloaded function
6167 names and member function names, and can do command completion on such names
6168 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6169 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6170 Make use of command completion, it is your friend.
6172 GDB also now accepts a variety of C++ mangled symbol formats. They are
6173 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6174 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6175 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6176 for the list of formats.
6178 * G++ symbol mangling problem
6180 Recent versions of gcc have a bug in how they emit debugging information for
6181 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6182 directory) can be applied to gcc to fix the problem. Alternatively, if you
6183 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6184 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6185 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6188 * New 'maintenance' command
6190 All of the commands related to hacking GDB internals have been moved out of
6191 the main command set, and now live behind the 'maintenance' command. This
6192 can also be abbreviated as 'mt'. The following changes were made:
6194 dump-me -> maintenance dump-me
6195 info all-breakpoints -> maintenance info breakpoints
6196 printmsyms -> maintenance print msyms
6197 printobjfiles -> maintenance print objfiles
6198 printpsyms -> maintenance print psymbols
6199 printsyms -> maintenance print symbols
6201 The following commands are new:
6203 maintenance demangle Call internal GDB demangler routine to
6204 demangle a C++ link name and prints the result.
6205 maintenance print type Print a type chain for a given symbol
6207 * Change to .gdbinit file processing
6209 We now read the $HOME/.gdbinit file before processing the argv arguments
6210 (e.g. reading symbol files or core files). This allows global parameters to
6211 be set, which will apply during the symbol reading. The ./.gdbinit is still
6212 read after argv processing.
6214 * New hosts supported
6216 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6218 GNU/Linux support i386-unknown-linux or linux
6220 We are also including code to support the HP/PA running BSD and HPUX. This
6221 is almost guaranteed not to work, as we didn't have time to test or build it
6222 for this release. We are including it so that the more adventurous (or
6223 masochistic) of you can play with it. We also had major problems with the
6224 fact that the compiler that we got from HP doesn't support the -g option.
6227 * New targets supported
6229 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6231 * More smarts about finding #include files
6233 GDB now remembers the compilation directory for all include files, and for
6234 all files from which C is generated (like yacc and lex sources). This
6235 greatly improves GDB's ability to find yacc/lex sources, and include files,
6236 especially if you are debugging your program from a directory different from
6237 the one that contains your sources.
6239 We also fixed a bug which caused difficulty with listing and setting
6240 breakpoints in include files which contain C code. (In the past, you had to
6241 try twice in order to list an include file that you hadn't looked at before.)
6243 * Interesting infernals change
6245 GDB now deals with arbitrary numbers of sections, where the symbols for each
6246 section must be relocated relative to that section's landing place in the
6247 target's address space. This work was needed to support ELF with embedded
6248 stabs used by Solaris-2.0.
6250 * Bug fixes (of course!)
6252 There have been loads of fixes for the following things:
6253 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6254 i960, stabs, DOS(GO32), procfs, etc...
6256 See the ChangeLog for details.
6258 *** Changes in GDB-4.5:
6260 * New machines supported (host and target)
6262 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6264 SGI Irix-4.x mips-sgi-irix4 or iris4
6266 * New malloc package
6268 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6269 Mmalloc is capable of handling mutiple heaps of memory. It is also
6270 capable of saving a heap to a file, and then mapping it back in later.
6271 This can be used to greatly speedup the startup of GDB by using a
6272 pre-parsed symbol table which lives in a mmalloc managed heap. For
6273 more details, please read mmalloc/mmalloc.texi.
6277 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6278 'help info proc' for details.
6280 * MIPS ecoff symbol table format
6282 The code that reads MIPS symbol table format is now supported on all hosts.
6283 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6286 * File name changes for MS-DOS
6288 Many files in the config directories have been renamed to make it easier to
6289 support GDB on MS-DOSe systems (which have very restrictive file name
6290 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6291 environment) is close to working but has some remaining problems. Note
6292 that debugging of DOS programs is not supported, due to limitations
6293 in the ``operating system'', but it can be used to host cross-debugging.
6295 * Cross byte order fixes
6297 Many fixes have been made to support cross debugging of Sparc and MIPS
6298 targets from hosts whose byte order differs.
6300 * New -mapped and -readnow options
6302 If memory-mapped files are available on your system through the 'mmap'
6303 system call, you can use the -mapped option on the `file' or
6304 `symbol-file' commands to cause GDB to write the symbols from your
6305 program into a reusable file. If the program you are debugging is
6306 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6307 Future GDB debugging sessions will notice the presence of this file,
6308 and will quickly map in symbol information from it, rather than reading
6309 the symbol table from the executable program. Using the '-mapped'
6310 option in a GDB `file' or `symbol-file' command has the same effect as
6311 starting GDB with the '-mapped' command-line option.
6313 You can cause GDB to read the entire symbol table immediately by using
6314 the '-readnow' option with any of the commands that load symbol table
6315 information (or on the GDB command line). This makes the command
6316 slower, but makes future operations faster.
6318 The -mapped and -readnow options are typically combined in order to
6319 build a `fred.syms' file that contains complete symbol information.
6320 A simple GDB invocation to do nothing but build a `.syms' file for future
6323 gdb -batch -nx -mapped -readnow programname
6325 The `.syms' file is specific to the host machine on which GDB is run.
6326 It holds an exact image of GDB's internal symbol table. It cannot be
6327 shared across multiple host platforms.
6329 * longjmp() handling
6331 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6332 siglongjmp() without losing control. This feature has not yet been ported to
6333 all systems. It currently works on many 386 platforms, all MIPS-based
6334 platforms (SGI, DECstation, etc), and Sun3/4.
6338 Preliminary work has been put in to support the new Solaris OS from Sun. At
6339 this time, it can control and debug processes, but it is not capable of
6344 As always, many many bug fixes. The major areas were with g++, and mipsread.
6345 People using the MIPS-based platforms should experience fewer mysterious
6346 crashes and trashed symbol tables.
6348 *** Changes in GDB-4.4:
6350 * New machines supported (host and target)
6352 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6354 BSD Reno on Vax vax-dec-bsd
6355 Ultrix on Vax vax-dec-ultrix
6357 * New machines supported (target)
6359 AMD 29000 embedded, using EBMON a29k-none-none
6363 GDB continues to improve its handling of C++. `References' work better.
6364 The demangler has also been improved, and now deals with symbols mangled as
6365 per the Annotated C++ Reference Guide.
6367 GDB also now handles `stabs' symbol information embedded in MIPS
6368 `ecoff' symbol tables. Since the ecoff format was not easily
6369 extensible to handle new languages such as C++, this appeared to be a
6370 good way to put C++ debugging info into MIPS binaries. This option
6371 will be supported in the GNU C compiler, version 2, when it is
6374 * New features for SVR4
6376 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6377 shared libraries. Debugging dynamically linked programs should present
6378 only minor differences from debugging statically linked programs.
6380 The `info proc' command will print out information about any process
6381 on an SVR4 system (including the one you are debugging). At the moment,
6382 it prints the address mappings of the process.
6384 If you bring up GDB on another SVR4 system, please send mail to
6385 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6387 * Better dynamic linking support in SunOS
6389 Reading symbols from shared libraries which contain debugging symbols
6390 now works properly. However, there remain issues such as automatic
6391 skipping of `transfer vector' code during function calls, which
6392 make it harder to debug code in a shared library, than to debug the
6393 same code linked statically.
6397 GDB is now using the latest `getopt' routines from the FSF. This
6398 version accepts the -- prefix for options with long names. GDB will
6399 continue to accept the old forms (-option and +option) as well.
6400 Various single letter abbreviations for options have been explicity
6401 added to the option table so that they won't get overshadowed in the
6402 future by other options that begin with the same letter.
6406 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6407 Many assorted bugs have been handled. Many more remain to be handled.
6408 See the various ChangeLog files (primarily in gdb and bfd) for details.
6411 *** Changes in GDB-4.3:
6413 * New machines supported (host and target)
6415 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6416 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6417 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6419 * Almost SCO Unix support
6421 We had hoped to support:
6422 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6423 (except for core file support), but we discovered very late in the release
6424 that it has problems with process groups that render gdb unusable. Sorry
6425 about that. I encourage people to fix it and post the fixes.
6427 * Preliminary ELF and DWARF support
6429 GDB can read ELF object files on System V Release 4, and can handle
6430 debugging records for C, in DWARF format, in ELF files. This support
6431 is preliminary. If you bring up GDB on another SVR4 system, please
6432 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6437 GDB now uses the latest `readline' library. One user-visible change
6438 is that two tabs will list possible command completions, which previously
6439 required typing M-? (meta-question mark, or ESC ?).
6443 The `stepi' bug that many of you noticed has been squashed.
6444 Many bugs in C++ have been handled. Many more remain to be handled.
6445 See the various ChangeLog files (primarily in gdb and bfd) for details.
6447 * State of the MIPS world (in case you wondered):
6449 GDB can understand the symbol tables emitted by the compilers
6450 supplied by most vendors of MIPS-based machines, including DEC. These
6451 symbol tables are in a format that essentially nobody else uses.
6453 Some versions of gcc come with an assembler post-processor called
6454 mips-tfile. This program is required if you want to do source-level
6455 debugging of gcc-compiled programs. I believe FSF does not ship
6456 mips-tfile with gcc version 1, but it will eventually come with gcc
6459 Debugging of g++ output remains a problem. g++ version 1.xx does not
6460 really support it at all. (If you're lucky, you should be able to get
6461 line numbers and stack traces to work, but no parameters or local
6462 variables.) With some work it should be possible to improve the
6465 When gcc version 2 is released, you will have somewhat better luck.
6466 However, even then you will get confusing results for inheritance and
6469 We will eventually provide full debugging of g++ output on
6470 DECstations. This will probably involve some kind of stabs-in-ecoff
6471 encapulation, but the details have not been worked out yet.
6474 *** Changes in GDB-4.2:
6476 * Improved configuration
6478 Only one copy of `configure' exists now, and it is not self-modifying.
6479 Porting BFD is simpler.
6483 The `step' and `next' commands now only stop at the first instruction
6484 of a source line. This prevents the multiple stops that used to occur
6485 in switch statements, for-loops, etc. `Step' continues to stop if a
6486 function that has debugging information is called within the line.
6490 Lots of small bugs fixed. More remain.
6492 * New host supported (not target)
6494 Intel 386 PC clone running Mach i386-none-mach
6497 *** Changes in GDB-4.1:
6499 * Multiple source language support
6501 GDB now has internal scaffolding to handle several source languages.
6502 It determines the type of each source file from its filename extension,
6503 and will switch expression parsing and number formatting to match the
6504 language of the function in the currently selected stack frame.
6505 You can also specifically set the language to be used, with
6506 `set language c' or `set language modula-2'.
6510 GDB now has preliminary support for the GNU Modula-2 compiler,
6511 currently under development at the State University of New York at
6512 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6513 continue through the fall of 1991 and into 1992.
6515 Other Modula-2 compilers are currently not supported, and attempting to
6516 debug programs compiled with them will likely result in an error as the
6517 symbol table is read. Feel free to work on it, though!
6519 There are hooks in GDB for strict type checking and range checking,
6520 in the `Modula-2 philosophy', but they do not currently work.
6524 GDB can now write to executable and core files (e.g. patch
6525 a variable's value). You must turn this switch on, specify
6526 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6527 by assigning a new value to a variable. Modifications take
6530 * Automatic SunOS shared library reading
6532 When you run your program, GDB automatically determines where its
6533 shared libraries (if any) have been loaded, and reads their symbols.
6534 The `share' command is no longer needed. This also works when
6535 examining core files.
6539 You can specify the number of lines that the `list' command shows.
6542 * New machines supported (host and target)
6544 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6545 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6546 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6548 * New hosts supported (not targets)
6550 IBM RT/PC: romp-ibm-aix or rtpc
6552 * New targets supported (not hosts)
6554 AMD 29000 embedded with COFF a29k-none-coff
6555 AMD 29000 embedded with a.out a29k-none-aout
6556 Ultracomputer remote kernel debug a29k-nyu-kern
6558 * New remote interfaces
6564 *** Changes in GDB-4.0:
6568 Wide output is wrapped at good places to make the output more readable.
6570 Gdb now supports cross-debugging from a host machine of one type to a
6571 target machine of another type. Communication with the target system
6572 is over serial lines. The ``target'' command handles connecting to the
6573 remote system; the ``load'' command will download a program into the
6574 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6575 also supports debugging of realtime processes running under VxWorks,
6576 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6577 stub on the target system.
6579 New CPUs supported include the AMD 29000 and Intel 960.
6581 GDB now reads object files and symbol tables via a ``binary file''
6582 library, which allows a single copy of GDB to debug programs of multiple
6583 object file types such as a.out and coff.
6585 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6586 refcard.dvi and refcard.ps are available to format it).
6589 * Control-Variable user interface simplified
6591 All variables that control the operation of the debugger can be set
6592 by the ``set'' command, and displayed by the ``show'' command.
6594 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6595 ``Show prompt'' produces the response:
6596 Gdb's prompt is new-gdb=>.
6598 What follows are the NEW set commands. The command ``help set'' will
6599 print a complete list of old and new set commands. ``help set FOO''
6600 will give a longer description of the variable FOO. ``show'' will show
6601 all of the variable descriptions and their current settings.
6603 confirm on/off: Enables warning questions for operations that are
6604 hard to recover from, e.g. rerunning the program while
6605 it is already running. Default is ON.
6607 editing on/off: Enables EMACS style command line editing
6608 of input. Previous lines can be recalled with
6609 control-P, the current line can be edited with control-B,
6610 you can search for commands with control-R, etc.
6613 history filename NAME: NAME is where the gdb command history
6614 will be stored. The default is .gdb_history,
6615 or the value of the environment variable
6618 history size N: The size, in commands, of the command history. The
6619 default is 256, or the value of the environment variable
6622 history save on/off: If this value is set to ON, the history file will
6623 be saved after exiting gdb. If set to OFF, the
6624 file will not be saved. The default is OFF.
6626 history expansion on/off: If this value is set to ON, then csh-like
6627 history expansion will be performed on
6628 command line input. The default is OFF.
6630 radix N: Sets the default radix for input and output. It can be set
6631 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6632 in the current radix, so "set radix 10" is always a no-op.
6634 height N: This integer value is the number of lines on a page. Default
6635 is 24, the current `stty rows'' setting, or the ``li#''
6636 setting from the termcap entry matching the environment
6639 width N: This integer value is the number of characters on a line.
6640 Default is 80, the current `stty cols'' setting, or the ``co#''
6641 setting from the termcap entry matching the environment
6644 Note: ``set screensize'' is obsolete. Use ``set height'' and
6645 ``set width'' instead.
6647 print address on/off: Print memory addresses in various command displays,
6648 such as stack traces and structure values. Gdb looks
6649 more ``symbolic'' if you turn this off; it looks more
6650 ``machine level'' with it on. Default is ON.
6652 print array on/off: Prettyprint arrays. New convenient format! Default
6655 print demangle on/off: Print C++ symbols in "source" form if on,
6658 print asm-demangle on/off: Same, for assembler level printouts
6661 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6664 * Support for Epoch Environment.
6666 The epoch environment is a version of Emacs v18 with windowing. One
6667 new command, ``inspect'', is identical to ``print'', except that if you
6668 are running in the epoch environment, the value is printed in its own
6672 * Support for Shared Libraries
6674 GDB can now debug programs and core files that use SunOS shared libraries.
6675 Symbols from a shared library cannot be referenced
6676 before the shared library has been linked with the program (this
6677 happens after you type ``run'' and before the function main() is entered).
6678 At any time after this linking (including when examining core files
6679 from dynamically linked programs), gdb reads the symbols from each
6680 shared library when you type the ``sharedlibrary'' command.
6681 It can be abbreviated ``share''.
6683 sharedlibrary REGEXP: Load shared object library symbols for files
6684 matching a unix regular expression. No argument
6685 indicates to load symbols for all shared libraries.
6687 info sharedlibrary: Status of loaded shared libraries.
6692 A watchpoint stops execution of a program whenever the value of an
6693 expression changes. Checking for this slows down execution
6694 tremendously whenever you are in the scope of the expression, but is
6695 quite useful for catching tough ``bit-spreader'' or pointer misuse
6696 problems. Some machines such as the 386 have hardware for doing this
6697 more quickly, and future versions of gdb will use this hardware.
6699 watch EXP: Set a watchpoint (breakpoint) for an expression.
6701 info watchpoints: Information about your watchpoints.
6703 delete N: Deletes watchpoint number N (same as breakpoints).
6704 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6705 enable N: Re-enables watchpoint number N (same as breakpoints).
6708 * C++ multiple inheritance
6710 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6713 * C++ exception handling
6715 Gdb now supports limited C++ exception handling. Besides the existing
6716 ability to breakpoint on an exception handler, gdb can breakpoint on
6717 the raising of an exception (before the stack is peeled back to the
6720 catch FOO: If there is a FOO exception handler in the dynamic scope,
6721 set a breakpoint to catch exceptions which may be raised there.
6722 Multiple exceptions (``catch foo bar baz'') may be caught.
6724 info catch: Lists all exceptions which may be caught in the
6725 current stack frame.
6728 * Minor command changes
6730 The command ``call func (arg, arg, ...)'' now acts like the print
6731 command, except it does not print or save a value if the function's result
6732 is void. This is similar to dbx usage.
6734 The ``up'' and ``down'' commands now always print the frame they end up
6735 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6736 frames without printing.
6738 * New directory command
6740 'dir' now adds directories to the FRONT of the source search path.
6741 The path starts off empty. Source files that contain debug information
6742 about the directory in which they were compiled can be found even
6743 with an empty path; Sun CC and GCC include this information. If GDB can't
6744 find your source file in the current directory, type "dir .".
6746 * Configuring GDB for compilation
6748 For normal use, type ``./configure host''. See README or gdb.texinfo
6751 GDB now handles cross debugging. If you are remotely debugging between
6752 two different machines, type ``./configure host -target=targ''.
6753 Host is the machine where GDB will run; targ is the machine
6754 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob