1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.0
6 * On Unix systems, GDBserver now does globbing expansion and variable
7 substitution in inferior command line arguments.
9 This is done by starting inferiors using a shell, like GDB does.
10 See "set startup-with-shell" in the user manual for how to disable
11 this from GDB when using "target extended-remote". When using
12 "target remote", you can disable the startup with shell by using the
13 new "--no-startup-with-shell" GDBserver command line option.
18 Indicates whether the inferior must be started with a shell or not.
20 * The "maintenance print c-tdesc" command now takes an optional
21 argument which is the file name of XML target description.
25 set debug separate-debug-file
26 show debug separate-debug-file
27 Control the display of debug output about separate debug file search.
29 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
32 *** Changes in GDB 8.0
34 * GDB now supports access to the PKU register on GNU/Linux. The register is
35 added by the Memory Protection Keys for Userspace feature which will be
36 available in future Intel CPUs.
38 * GDB now supports C++11 rvalue references.
42 ** New functions to start, stop and access a running btrace recording.
43 ** Rvalue references are now supported in gdb.Type.
45 * GDB now supports recording and replaying rdrand and rdseed Intel 64
48 * Building GDB and GDBserver now requires a C++11 compiler.
50 For example, GCC 4.8 or later.
52 It is no longer possible to build GDB or GDBserver with a C
53 compiler. The --disable-build-with-cxx configure option has been
56 * Building GDB and GDBserver now requires GNU make >= 3.81.
58 It is no longer supported to build GDB or GDBserver with another
59 implementation of the make program or an earlier version of GNU make.
61 * Native debugging on MS-Windows supports command-line redirection
63 Command-line arguments used for starting programs on MS-Windows can
64 now include redirection symbols supported by native Windows shells,
65 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
66 as "run", "start", and "set args", as well as the corresponding MI
69 * Support for thread names on MS-Windows.
71 GDB now catches and handles the special exception that programs
72 running on MS-Windows use to assign names to threads in the
75 * Support for Java programs compiled with gcj has been removed.
77 * User commands now accept an unlimited number of arguments.
78 Previously, only up to 10 was accepted.
80 * The "eval" command now expands user-defined command arguments.
82 This makes it easier to process a variable number of arguments:
87 eval "print $arg%d", $i
92 * Target descriptions can now describe registers for sparc32 and sparc64.
94 * GDB now supports DWARF version 5 (debug information format).
95 Its .debug_names index is not yet supported.
97 * New native configurations
99 FreeBSD/mips mips*-*-freebsd
103 Synopsys ARC arc*-*-elf32
104 FreeBSD/mips mips*-*-freebsd
106 * Removed targets and native configurations
108 Alpha running FreeBSD alpha*-*-freebsd*
109 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
114 Erases all the flash memory regions reported by the target.
116 maint print arc arc-instruction address
117 Print internal disassembler information about instruction at a given address.
121 set disassembler-options
122 show disassembler-options
123 Controls the passing of target specific information to the disassembler.
124 If it is necessary to specify more than one disassembler option then
125 multiple options can be placed together into a comma separated list.
126 The default value is the empty string. Currently, the only supported
127 targets are ARM, PowerPC and S/390.
132 Erases all the flash memory regions reported by the target. This is
133 equivalent to the CLI command flash-erase.
135 -file-list-shared-libraries
136 List the shared libraries in the program. This is
137 equivalent to the CLI command "info shared".
139 *** Changes in GDB 7.12
141 * GDB and GDBserver now build with a C++ compiler by default.
143 The --enable-build-with-cxx configure option is now enabled by
144 default. One must now explicitly configure with
145 --disable-build-with-cxx in order to build with a C compiler. This
146 option will be removed in a future release.
148 * GDBserver now supports recording btrace without maintaining an active
151 * GDB now supports a negative repeat count in the 'x' command to examine
152 memory backward from the given address. For example:
155 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
156 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
157 (gdb) x/-5i 0x0000000000400580
158 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
159 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
160 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
161 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
162 0x40057b <main(int, char**)+25>:
163 callq 0x400536 <Func1(int, char const*)>
165 * Fortran: Support structures with fields of dynamic types and
166 arrays of dynamic types.
168 * The symbol dumping maintenance commands have new syntax.
169 maint print symbols [-pc address] [--] [filename]
170 maint print symbols [-objfile objfile] [-source source] [--] [filename]
171 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
172 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
173 maint print msymbols [-objfile objfile] [--] [filename]
175 * GDB now supports multibit bitfields and enums in target register
178 * New Python-based convenience function $_as_string(val), which returns
179 the textual representation of a value. This function is especially
180 useful to obtain the text label of an enum value.
182 * Intel MPX bound violation handling.
184 Segmentation faults caused by a Intel MPX boundary violation
185 now display the kind of violation (upper or lower), the memory
186 address accessed and the memory bounds, along with the usual
187 signal received and code location.
191 Program received signal SIGSEGV, Segmentation fault
192 Upper bound violation while accessing address 0x7fffffffc3b3
193 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
194 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
196 * Rust language support.
197 GDB now supports debugging programs written in the Rust programming
198 language. See https://www.rust-lang.org/ for more information about
201 * Support for running interpreters on specified input/output devices
203 GDB now supports a new mechanism that allows frontends to provide
204 fully featured GDB console views, as a better alternative to
205 building such views on top of the "-interpreter-exec console"
206 command. See the new "new-ui" command below. With that command,
207 frontends can now start GDB in the traditional command-line mode
208 running in an embedded terminal emulator widget, and create a
209 separate MI interpreter running on a specified i/o device. In this
210 way, GDB handles line editing, history, tab completion, etc. in the
211 console all by itself, and the GUI uses the separate MI interpreter
212 for its own control and synchronization, invisible to the command
215 * The "catch syscall" command catches groups of related syscalls.
217 The "catch syscall" command now supports catching a group of related
218 syscalls using the 'group:' or 'g:' prefix.
223 skip -gfile file-glob-pattern
224 skip -function function
225 skip -rfunction regular-expression
226 A generalized form of the skip command, with new support for
227 glob-style file names and regular expressions for function names.
228 Additionally, a file spec and a function spec may now be combined.
230 maint info line-table REGEXP
231 Display the contents of GDB's internal line table data struture.
234 Run any GDB unit tests that were compiled in.
237 Start a new user interface instance running INTERP as interpreter,
238 using the TTY file for input/output.
242 ** gdb.Breakpoint objects have a new attribute "pending", which
243 indicates whether the breakpoint is pending.
244 ** Three new breakpoint-related events have been added:
245 gdb.breakpoint_created, gdb.breakpoint_modified, and
246 gdb.breakpoint_deleted.
249 Signal ("set") the given MS-Windows event object. This is used in
250 conjunction with the Windows JIT debugging (AeDebug) support, where
251 the OS suspends a crashing process until a debugger can attach to
252 it. Resuming the crashing process, in order to debug it, is done by
255 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
256 was added in GDBserver, including JIT compiling fast tracepoint's
257 conditional expression bytecode into native code.
259 * Support for various remote target protocols and ROM monitors has
262 target m32rsdi Remote M32R debugging over SDI
263 target mips MIPS remote debugging protocol
264 target pmon PMON ROM monitor
265 target ddb NEC's DDB variant of PMON for Vr4300
266 target rockhopper NEC RockHopper variant of PMON
267 target lsi LSI variant of PMO
269 * Support for tracepoints and fast tracepoints on powerpc-linux,
270 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
271 including JIT compiling fast tracepoint's conditional expression
272 bytecode into native code.
274 * MI async record =record-started now includes the method and format used for
275 recording. For example:
277 =record-started,thread-group="i1",method="btrace",format="bts"
279 * MI async record =thread-selected now includes the frame field. For example:
281 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
285 Andes NDS32 nds32*-*-elf
287 *** Changes in GDB 7.11
289 * GDB now supports debugging kernel-based threads on FreeBSD.
291 * Per-inferior thread numbers
293 Thread numbers are now per inferior instead of global. If you're
294 debugging multiple inferiors, GDB displays thread IDs using a
295 qualified INF_NUM.THR_NUM form. For example:
299 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
300 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
301 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
302 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
304 As consequence, thread numbers as visible in the $_thread
305 convenience variable and in Python's InferiorThread.num attribute
306 are no longer unique between inferiors.
308 GDB now maintains a second thread ID per thread, referred to as the
309 global thread ID, which is the new equivalent of thread numbers in
310 previous releases. See also $_gthread below.
312 For backwards compatibility, MI's thread IDs always refer to global
315 * Commands that accept thread IDs now accept the qualified
316 INF_NUM.THR_NUM form as well. For example:
319 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
322 * In commands that accept a list of thread IDs, you can now refer to
323 all threads of an inferior using a star wildcard. GDB accepts
324 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
325 refer to all threads of the current inferior. For example, "info
328 * You can use "info threads -gid" to display the global thread ID of
331 * The new convenience variable $_gthread holds the global number of
334 * The new convenience variable $_inferior holds the number of the
337 * GDB now displays the ID and name of the thread that hit a breakpoint
338 or received a signal, if your program is multi-threaded. For
341 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
342 Thread 1 "main" received signal SIGINT, Interrupt.
344 * Record btrace now supports non-stop mode.
346 * Support for tracepoints on aarch64-linux was added in GDBserver.
348 * The 'record instruction-history' command now indicates speculative execution
349 when using the Intel Processor Trace recording format.
351 * GDB now allows users to specify explicit locations, bypassing
352 the linespec parser. This feature is also available to GDB/MI
355 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
356 GDB now is able to debug both AArch64 applications and ARM applications
359 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
360 including JIT compiling fast tracepoint's conditional expression bytecode
363 * GDB now supports displaced stepping on AArch64 GNU/Linux.
365 * "info threads", "info inferiors", "info display", "info checkpoints"
366 and "maint info program-spaces" now list the corresponding items in
367 ascending ID order, for consistency with all other "info" commands.
369 * In Ada, the overloads selection menu has been enhanced to display the
370 parameter types and the return types for the matching overloaded subprograms.
374 maint set target-non-stop (on|off|auto)
375 maint show target-non-stop
376 Control whether GDB targets always operate in non-stop mode even if
377 "set non-stop" is "off". The default is "auto", meaning non-stop
378 mode is enabled if supported by the target.
380 maint set bfd-sharing
381 maint show bfd-sharing
382 Control the reuse of bfd objects.
386 Control display of debugging info regarding bfd caching.
390 Control display of debugging info regarding FreeBSD threads.
392 set remote multiprocess-extensions-packet
393 show remote multiprocess-extensions-packet
394 Set/show the use of the remote protocol multiprocess extensions.
396 set remote thread-events
397 show remote thread-events
398 Set/show the use of thread create/exit events.
400 set ada print-signatures on|off
401 show ada print-signatures"
402 Control whether parameter types and return types are displayed in overloads
403 selection menus. It is activaled (@code{on}) by default.
407 Controls the maximum size of memory, in bytes, that GDB will
408 allocate for value contents. Prevents incorrect programs from
409 causing GDB to allocate overly large buffers. Default is 64k.
411 * The "disassemble" command accepts a new modifier: /s.
412 It prints mixed source+disassembly like /m with two differences:
413 - disassembled instructions are now printed in program order, and
414 - and source for all relevant files is now printed.
415 The "/m" option is now considered deprecated: its "source-centric"
416 output hasn't proved useful in practice.
418 * The "record instruction-history" command accepts a new modifier: /s.
419 It behaves exactly like /m and prints mixed source+disassembly.
421 * The "set scheduler-locking" command supports a new mode "replay".
422 It behaves like "off" in record mode and like "on" in replay mode.
424 * Support for various ROM monitors has been removed:
426 target dbug dBUG ROM monitor for Motorola ColdFire
427 target picobug Motorola picobug monitor
428 target dink32 DINK32 ROM monitor for PowerPC
429 target m32r Renesas M32R/D ROM monitor
430 target mon2000 mon2000 ROM monitor
431 target ppcbug PPCBUG ROM monitor for PowerPC
433 * Support for reading/writing memory and extracting values on architectures
434 whose memory is addressable in units of any integral multiple of 8 bits.
439 Indicates whether the inferior must be started with a shell or not.
442 Indicates that an exec system call was executed.
444 exec-events feature in qSupported
445 The qSupported packet allows GDB to request support for exec
446 events using the new 'gdbfeature' exec-event, and the qSupported
447 response can contain the corresponding 'stubfeature'. Set and
448 show commands can be used to display whether these features are enabled.
451 Equivalent to interrupting with the ^C character, but works in
454 thread created stop reason (T05 create:...)
455 Indicates that the thread was just created and is stopped at entry.
457 thread exit stop reply (w exitcode;tid)
458 Indicates that the thread has terminated.
461 Enables/disables thread create and exit event reporting. For
462 example, this is used in non-stop mode when GDB stops a set of
463 threads and synchronously waits for the their corresponding stop
464 replies. Without exit events, if one of the threads exits, GDB
465 would hang forever not knowing that it should no longer expect a
466 stop for that same thread.
469 Indicates that there are no resumed threads left in the target (all
470 threads are stopped). The remote stub reports support for this stop
471 reply to GDB's qSupported query.
474 Enables/disables catching syscalls from the inferior process.
475 The remote stub reports support for this packet to GDB's qSupported query.
477 syscall_entry stop reason
478 Indicates that a syscall was just called.
480 syscall_return stop reason
481 Indicates that a syscall just returned.
483 * Extended-remote exec events
485 ** GDB now has support for exec events on extended-remote Linux targets.
486 For such targets with Linux kernels 2.5.46 and later, this enables
487 follow-exec-mode and exec catchpoints.
489 set remote exec-event-feature-packet
490 show remote exec-event-feature-packet
491 Set/show the use of the remote exec event feature.
493 * Thread names in remote protocol
495 The reply to qXfer:threads:read may now include a name attribute for each
498 * Target remote mode fork and exec events
500 ** GDB now has support for fork and exec events on target remote mode
501 Linux targets. For such targets with Linux kernels 2.5.46 and later,
502 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
503 fork and exec catchpoints.
505 * Remote syscall events
507 ** GDB now has support for catch syscall on remote Linux targets,
508 currently enabled on x86/x86_64 architectures.
510 set remote catch-syscall-packet
511 show remote catch-syscall-packet
512 Set/show the use of the remote catch syscall feature.
516 ** The -var-set-format command now accepts the zero-hexadecimal
517 format. It outputs data in hexadecimal format with zero-padding on the
522 ** gdb.InferiorThread objects have a new attribute "global_num",
523 which refers to the thread's global thread ID. The existing
524 "num" attribute now refers to the thread's per-inferior number.
525 See "Per-inferior thread numbers" above.
526 ** gdb.InferiorThread objects have a new attribute "inferior", which
527 is the Inferior object the thread belongs to.
529 *** Changes in GDB 7.10
531 * Support for process record-replay and reverse debugging on aarch64*-linux*
532 targets has been added. GDB now supports recording of A64 instruction set
533 including advance SIMD instructions.
535 * Support for Sun's version of the "stabs" debug file format has been removed.
537 * GDB now honors the content of the file /proc/PID/coredump_filter
538 (PID is the process ID) on GNU/Linux systems. This file can be used
539 to specify the types of memory mappings that will be included in a
540 corefile. For more information, please refer to the manual page of
541 "core(5)". GDB also has a new command: "set use-coredump-filter
542 on|off". It allows to set whether GDB will read the content of the
543 /proc/PID/coredump_filter file when generating a corefile.
545 * The "info os" command on GNU/Linux can now display information on
547 "info os cpus" Listing of all cpus/cores on the system
549 * GDB has two new commands: "set serial parity odd|even|none" and
550 "show serial parity". These allows to set or show parity for the
553 * The "info source" command now displays the producer string if it was
554 present in the debug info. This typically includes the compiler version
555 and may include things like its command line arguments.
557 * The "info dll", an alias of the "info sharedlibrary" command,
558 is now available on all platforms.
560 * Directory names supplied to the "set sysroot" commands may be
561 prefixed with "target:" to tell GDB to access shared libraries from
562 the target system, be it local or remote. This replaces the prefix
563 "remote:". The default sysroot has been changed from "" to
564 "target:". "remote:" is automatically converted to "target:" for
565 backward compatibility.
567 * The system root specified by "set sysroot" will be prepended to the
568 filename of the main executable (if reported to GDB as absolute by
569 the operating system) when starting processes remotely, and when
570 attaching to already-running local or remote processes.
572 * GDB now supports automatic location and retrieval of executable
573 files from remote targets. Remote debugging can now be initiated
574 using only a "target remote" or "target extended-remote" command
575 (no "set sysroot" or "file" commands are required). See "New remote
578 * The "dump" command now supports verilog hex format.
580 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
582 * On GNU/Linux, GDB and gdbserver are now able to access executable
583 and shared library files without a "set sysroot" command when
584 attaching to processes running in different mount namespaces from
585 the debugger. This makes it possible to attach to processes in
586 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
587 See "New remote packets" below.
589 * The "tui reg" command now provides completion for all of the
590 available register groups, including target specific groups.
592 * The HISTSIZE environment variable is no longer read when determining
593 the size of GDB's command history. GDB now instead reads the dedicated
594 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
595 disables truncation of command history. Non-numeric values of GDBHISTSIZE
600 ** Memory ports can now be unbuffered.
604 ** gdb.Objfile objects have a new attribute "username",
605 which is the name of the objfile as specified by the user,
606 without, for example, resolving symlinks.
607 ** You can now write frame unwinders in Python.
608 ** gdb.Type objects have a new method "optimized_out",
609 returning optimized out gdb.Value instance of this type.
610 ** gdb.Value objects have new methods "reference_value" and
611 "const_value" which return a reference to the value and a
612 "const" version of the value respectively.
616 maint print symbol-cache
617 Print the contents of the symbol cache.
619 maint print symbol-cache-statistics
620 Print statistics of symbol cache usage.
622 maint flush-symbol-cache
623 Flush the contents of the symbol cache.
627 Start branch trace recording using Branch Trace Store (BTS) format.
630 Evaluate expression by using the compiler and print result.
634 Explicit commands for enabling and disabling tui mode.
637 set mpx bound on i386 and amd64
638 Support for bound table investigation on Intel MPX enabled applications.
642 Start branch trace recording using Intel Processor Trace format.
645 Print information about branch tracing internals.
647 maint btrace packet-history
648 Print the raw branch tracing data.
650 maint btrace clear-packet-history
651 Discard the stored raw branch tracing data.
654 Discard all branch tracing data. It will be fetched and processed
655 anew by the next "record" command.
660 Renamed from "set debug dwarf2-die".
662 Renamed from "show debug dwarf2-die".
665 Renamed from "set debug dwarf2-read".
666 show debug dwarf-read
667 Renamed from "show debug dwarf2-read".
669 maint set dwarf always-disassemble
670 Renamed from "maint set dwarf2 always-disassemble".
671 maint show dwarf always-disassemble
672 Renamed from "maint show dwarf2 always-disassemble".
674 maint set dwarf max-cache-age
675 Renamed from "maint set dwarf2 max-cache-age".
676 maint show dwarf max-cache-age
677 Renamed from "maint show dwarf2 max-cache-age".
680 show debug dwarf-line
681 Control display of debugging info regarding DWARF line processing.
685 Set the maximum number of candidates to be considered during
686 completion. The default value is 200. This limit allows GDB
687 to avoid generating large completion lists, the computation of
688 which can cause the debugger to become temporarily unresponsive.
690 set history remove-duplicates
691 show history remove-duplicates
692 Control the removal of duplicate history entries.
694 maint set symbol-cache-size
695 maint show symbol-cache-size
696 Control the size of the symbol cache.
698 set|show record btrace bts buffer-size
699 Set and show the size of the ring buffer used for branch tracing in
701 The obtained size may differ from the requested size. Use "info
702 record" to see the obtained buffer size.
704 set debug linux-namespaces
705 show debug linux-namespaces
706 Control display of debugging info regarding Linux namespaces.
708 set|show record btrace pt buffer-size
709 Set and show the size of the ring buffer used for branch tracing in
710 Intel Processor Trace format.
711 The obtained size may differ from the requested size. Use "info
712 record" to see the obtained buffer size.
714 maint set|show btrace pt skip-pad
715 Set and show whether PAD packets are skipped when computing the
718 * The command 'thread apply all' can now support new option '-ascending'
719 to call its specified command for all threads in ascending order.
721 * Python/Guile scripting
723 ** GDB now supports auto-loading of Python/Guile scripts contained in the
724 special section named `.debug_gdb_scripts'.
728 qXfer:btrace-conf:read
729 Return the branch trace configuration for the current thread.
731 Qbtrace-conf:bts:size
732 Set the requested ring buffer size for branch tracing in BTS format.
735 Enable Intel Procesor Trace-based branch tracing for the current
736 process. The remote stub reports support for this packet to GDB's
740 Set the requested ring buffer size for branch tracing in Intel Processor
744 Indicates a memory breakpoint instruction was executed, irrespective
745 of whether it was GDB that planted the breakpoint or the breakpoint
746 is hardcoded in the program. This is required for correct non-stop
750 Indicates the target stopped for a hardware breakpoint. This is
751 required for correct non-stop mode operation.
754 Return information about files on the remote system.
757 Return the full absolute name of the file that was executed to
758 create a process running on the remote system.
761 Select the filesystem on which vFile: operations with filename
762 arguments will operate. This is required for GDB to be able to
763 access files on remote targets where the remote stub does not
764 share a common filesystem with the inferior(s).
767 Indicates that a fork system call was executed.
770 Indicates that a vfork system call was executed.
772 vforkdone stop reason
773 Indicates that a vfork child of the specified process has executed
774 an exec or exit, allowing the vfork parent to resume execution.
776 fork-events and vfork-events features in qSupported
777 The qSupported packet allows GDB to request support for fork and
778 vfork events using new 'gdbfeatures' fork-events and vfork-events,
779 and the qSupported response can contain the corresponding
780 'stubfeatures'. Set and show commands can be used to display
781 whether these features are enabled.
783 * Extended-remote fork events
785 ** GDB now has support for fork events on extended-remote Linux
786 targets. For targets with Linux kernels 2.5.60 and later, this
787 enables follow-fork-mode and detach-on-fork for both fork and
788 vfork, as well as fork and vfork catchpoints.
790 * The info record command now shows the recording format and the
791 branch tracing configuration for the current thread when using
792 the btrace record target.
793 For the BTS format, it shows the ring buffer size.
795 * GDB now has support for DTrace USDT (Userland Static Defined
796 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
798 * GDB now supports access to vector registers on S/390 GNU/Linux
801 * Removed command line options
803 -xdb HP-UX XDB compatibility mode.
805 * Removed targets and native configurations
807 HP/PA running HP-UX hppa*-*-hpux*
808 Itanium running HP-UX ia64-*-hpux*
810 * New configure options
813 This configure option allows the user to build GDB with support for
814 Intel Processor Trace (default: auto). This requires libipt.
816 --with-libipt-prefix=PATH
817 Specify the path to the version of libipt that GDB should use.
818 $PATH/include should contain the intel-pt.h header and
819 $PATH/lib should contain the libipt.so library.
821 *** Changes in GDB 7.9.1
825 ** Xmethods can now specify a result type.
827 *** Changes in GDB 7.9
829 * GDB now supports hardware watchpoints on x86 GNU Hurd.
833 ** You can now access frame registers from Python scripts.
834 ** New attribute 'producer' for gdb.Symtab objects.
835 ** gdb.Objfile objects have a new attribute "progspace",
836 which is the gdb.Progspace object of the containing program space.
837 ** gdb.Objfile objects have a new attribute "owner".
838 ** gdb.Objfile objects have a new attribute "build_id",
839 which is the build ID generated when the file was built.
840 ** gdb.Objfile objects have a new method "add_separate_debug_file".
841 ** A new event "gdb.clear_objfiles" has been added, triggered when
842 selecting a new file to debug.
843 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
844 ** New function gdb.lookup_objfile.
846 New events which are triggered when GDB modifies the state of the
849 ** gdb.events.inferior_call_pre: Function call is about to be made.
850 ** gdb.events.inferior_call_post: Function call has just been made.
851 ** gdb.events.memory_changed: A memory location has been altered.
852 ** gdb.events.register_changed: A register has been altered.
854 * New Python-based convenience functions:
856 ** $_caller_is(name [, number_of_frames])
857 ** $_caller_matches(regexp [, number_of_frames])
858 ** $_any_caller_is(name [, number_of_frames])
859 ** $_any_caller_matches(regexp [, number_of_frames])
861 * GDB now supports the compilation and injection of source code into
862 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
863 to compile the source code to object code, and if successful, inject
864 and execute that code within the current context of the inferior.
865 Currently the C language is supported. The commands used to
866 interface with this new feature are:
868 compile code [-raw|-r] [--] [source code]
869 compile file [-raw|-r] filename
873 demangle [-l language] [--] name
874 Demangle "name" in the specified language, or the current language
875 if elided. This command is renamed from the "maint demangle" command.
876 The latter is kept as a no-op to avoid "maint demangle" being interpreted
877 as "maint demangler-warning".
879 queue-signal signal-name-or-number
880 Queue a signal to be delivered to the thread when it is resumed.
882 add-auto-load-scripts-directory directory
883 Add entries to the list of directories from which to load auto-loaded
886 maint print user-registers
887 List all currently available "user" registers.
889 compile code [-r|-raw] [--] [source code]
890 Compile, inject, and execute in the inferior the executable object
891 code produced by compiling the provided source code.
893 compile file [-r|-raw] filename
894 Compile and inject into the inferior the executable object code
895 produced by compiling the source code stored in the filename
898 * On resume, GDB now always passes the signal the program had stopped
899 for to the thread the signal was sent to, even if the user changed
900 threads before resuming. Previously GDB would often (but not
901 always) deliver the signal to the thread that happens to be current
904 * Conversely, the "signal" command now consistently delivers the
905 requested signal to the current thread. GDB now asks for
906 confirmation if the program had stopped for a signal and the user
907 switched threads meanwhile.
909 * "breakpoint always-inserted" modes "off" and "auto" merged.
911 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
912 won't remove breakpoints from the target until all threads stop,
913 even in non-stop mode. The "auto" mode has been removed, and "off"
914 is now the default mode.
918 set debug symbol-lookup
919 show debug symbol-lookup
920 Control display of debugging info regarding symbol lookup.
924 ** The -list-thread-groups command outputs an exit-code field for
925 inferiors that have exited.
929 MIPS SDE mips*-sde*-elf*
933 Support for these obsolete configurations has been removed.
935 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
936 SGI Irix-5.x mips-*-irix5*
937 SGI Irix-6.x mips-*-irix6*
938 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
939 VAX running Ultrix vax-*-ultrix*
941 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
942 and "assf"), have been removed. Use the "sharedlibrary" command, or
943 its alias "share", instead.
945 *** Changes in GDB 7.8
947 * New command line options
950 This is an alias for the --data-directory option.
952 * GDB supports printing and modifying of variable length automatic arrays
953 as specified in ISO C99.
955 * The ARM simulator now supports instruction level tracing
956 with or without disassembly.
960 GDB now has support for scripting using Guile. Whether this is
961 available is determined at configure time.
962 Guile version 2.0 or greater is required.
963 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
965 * New commands (for set/show, see "New options" below)
969 Invoke CODE by passing it to the Guile interpreter.
973 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
975 info auto-load guile-scripts [regexp]
976 Print the list of automatically loaded Guile scripts.
978 * The source command is now capable of sourcing Guile scripts.
979 This feature is dependent on the debugger being built with Guile support.
983 set print symbol-loading (off|brief|full)
984 show print symbol-loading
985 Control whether to print informational messages when loading symbol
986 information for a file. The default is "full", but when debugging
987 programs with large numbers of shared libraries the amount of output
990 set guile print-stack (none|message|full)
991 show guile print-stack
992 Show a stack trace when an error is encountered in a Guile script.
994 set auto-load guile-scripts (on|off)
995 show auto-load guile-scripts
996 Control auto-loading of Guile script files.
998 maint ada set ignore-descriptive-types (on|off)
999 maint ada show ignore-descriptive-types
1000 Control whether the debugger should ignore descriptive types in Ada
1001 programs. The default is not to ignore the descriptive types. See
1002 the user manual for more details on descriptive types and the intended
1003 usage of this option.
1005 set auto-connect-native-target
1007 Control whether GDB is allowed to automatically connect to the
1008 native target for the run, attach, etc. commands when not connected
1009 to any target yet. See also "target native" below.
1011 set record btrace replay-memory-access (read-only|read-write)
1012 show record btrace replay-memory-access
1013 Control what memory accesses are allowed during replay.
1015 maint set target-async (on|off)
1016 maint show target-async
1017 This controls whether GDB targets operate in synchronous or
1018 asynchronous mode. Normally the default is asynchronous, if it is
1019 available; but this can be changed to more easily debug problems
1020 occurring only in synchronous mode.
1022 set mi-async (on|off)
1024 Control whether MI asynchronous mode is preferred. This supersedes
1025 "set target-async" of previous GDB versions.
1027 * "set target-async" is deprecated as a CLI option and is now an alias
1028 for "set mi-async" (only puts MI into async mode).
1030 * Background execution commands (e.g., "c&", "s&", etc.) are now
1031 possible ``out of the box'' if the target supports them. Previously
1032 the user would need to explicitly enable the possibility with the
1033 "set target-async on" command.
1035 * New features in the GDB remote stub, GDBserver
1037 ** New option --debug-format=option1[,option2,...] allows one to add
1038 additional text to each output. At present only timestamps
1039 are supported: --debug-format=timestamps.
1040 Timestamps can also be turned on with the
1041 "monitor set debug-format timestamps" command from GDB.
1043 * The 'record instruction-history' command now starts counting instructions
1044 at one. This also affects the instruction ranges reported by the
1045 'record function-call-history' command when given the /i modifier.
1047 * The command 'record function-call-history' supports a new modifier '/c' to
1048 indent the function names based on their call stack depth.
1049 The fields for the '/i' and '/l' modifier have been reordered.
1050 The source line range is now prefixed with 'at'.
1051 The instruction range is now prefixed with 'inst'.
1052 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1053 "record instruction-history" and "list" commands.
1055 * The ranges given as arguments to the 'record function-call-history' and
1056 'record instruction-history' commands are now inclusive.
1058 * The btrace record target now supports the 'record goto' command.
1059 For locations inside the execution trace, the back trace is computed
1060 based on the information stored in the execution trace.
1062 * The btrace record target supports limited reverse execution and replay.
1063 The target does not record data and therefore does not allow reading
1064 memory or registers.
1066 * The "catch syscall" command now works on s390*-linux* targets.
1068 * The "compare-sections" command is no longer specific to target
1069 remote. It now works with all targets.
1071 * All native targets are now consistently called "native".
1072 Consequently, the "target child", "target GNU", "target djgpp",
1073 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1074 commands have been replaced with "target native". The QNX/NTO port
1075 leaves the "procfs" target in place and adds a "native" target for
1076 consistency with other ports. The impact on users should be minimal
1077 as these commands previously either throwed an error, or were
1078 no-ops. The target's name is visible in the output of the following
1079 commands: "help target", "info target", "info files", "maint print
1082 * The "target native" command now connects to the native target. This
1083 can be used to launch native programs even when "set
1084 auto-connect-native-target" is set to off.
1086 * GDB now supports access to Intel MPX registers on GNU/Linux.
1088 * Support for Intel AVX-512 registers on GNU/Linux.
1089 Support displaying and modifying Intel AVX-512 registers
1090 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1092 * New remote packets
1094 qXfer:btrace:read's annex
1095 The qXfer:btrace:read packet supports a new annex 'delta' to read
1096 branch trace incrementally.
1100 ** Valid Python operations on gdb.Value objects representing
1101 structs/classes invoke the corresponding overloaded operators if
1103 ** New `Xmethods' feature in the Python API. Xmethods are
1104 additional methods or replacements for existing methods of a C++
1105 class. This feature is useful for those cases where a method
1106 defined in C++ source code could be inlined or optimized out by
1107 the compiler, making it unavailable to GDB.
1110 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1112 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1113 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1114 its alias "share", instead.
1116 * The commands "set remotebaud" and "show remotebaud" are no longer
1117 supported. Use "set serial baud" and "show serial baud" (respectively)
1122 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1123 target-async". The latter is left as a deprecated alias of the
1124 former for backward compatibility. If the target supports it,
1125 CLI background execution commands are now always possible by
1126 default, independently of whether the frontend stated a
1127 preference for asynchronous execution with "-gdb-set mi-async".
1128 Previously "-gdb-set target-async off" affected both MI execution
1129 commands and CLI execution commands.
1131 *** Changes in GDB 7.7
1133 * Improved support for process record-replay and reverse debugging on
1134 arm*-linux* targets. Support for thumb32 and syscall instruction
1135 recording has been added.
1137 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1139 * GDB now supports Fission DWP file format version 2.
1140 http://gcc.gnu.org/wiki/DebugFission
1142 * New convenience function "$_isvoid", to check whether an expression
1143 is void. A void expression is an expression where the type of the
1144 result is "void". For example, some convenience variables may be
1145 "void" when evaluated (e.g., "$_exitcode" before the execution of
1146 the program being debugged; or an undefined convenience variable).
1147 Another example, when calling a function whose return type is
1150 * The "maintenance print objfiles" command now takes an optional regexp.
1152 * The "catch syscall" command now works on arm*-linux* targets.
1154 * GDB now consistently shows "<not saved>" when printing values of
1155 registers the debug info indicates have not been saved in the frame
1156 and there's nowhere to retrieve them from
1157 (callee-saved/call-clobbered registers):
1162 (gdb) info registers rax
1165 Before, the former would print "<optimized out>", and the latter
1166 "*value not available*".
1168 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1173 ** Frame filters and frame decorators have been added.
1174 ** Temporary breakpoints are now supported.
1175 ** Line tables representation has been added.
1176 ** New attribute 'parent_type' for gdb.Field objects.
1177 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1178 ** New attribute 'name' for gdb.Type objects.
1182 Nios II ELF nios2*-*-elf
1183 Nios II GNU/Linux nios2*-*-linux
1184 Texas Instruments MSP430 msp430*-*-elf
1186 * Removed native configurations
1188 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1189 been removed. ELF variants of these configurations are kept supported.
1191 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1192 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1193 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1194 i[34567]86-*-openbsd3.[0-3]
1195 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1196 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1197 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1201 Like "catch throw", but catches a re-thrown exception.
1202 maint check-psymtabs
1203 Renamed from old "maint check-symtabs".
1205 Perform consistency checks on symtabs.
1206 maint expand-symtabs
1207 Expand symtabs matching an optional regexp.
1210 Display the details of GDB configure-time options.
1212 maint set|show per-command
1213 maint set|show per-command space
1214 maint set|show per-command time
1215 maint set|show per-command symtab
1216 Enable display of per-command gdb resource usage.
1218 remove-symbol-file FILENAME
1219 remove-symbol-file -a ADDRESS
1220 Remove a symbol file added via add-symbol-file. The file to remove
1221 can be identified by its filename or by an address that lies within
1222 the boundaries of this symbol file in memory.
1225 info exceptions REGEXP
1226 Display the list of Ada exceptions defined in the program being
1227 debugged. If provided, only the exceptions whose names match REGEXP
1232 set debug symfile off|on
1234 Control display of debugging info regarding reading symbol files and
1235 symbol tables within those files
1237 set print raw frame-arguments
1238 show print raw frame-arguments
1239 Set/show whether to print frame arguments in raw mode,
1240 disregarding any defined pretty-printers.
1242 set remote trace-status-packet
1243 show remote trace-status-packet
1244 Set/show the use of remote protocol qTStatus packet.
1248 Control display of debugging messages related to Nios II targets.
1252 Control whether target-assisted range stepping is enabled.
1254 set startup-with-shell
1255 show startup-with-shell
1256 Specifies whether Unix child processes are started via a shell or
1261 Use the target memory cache for accesses to the code segment. This
1262 improves performance of remote debugging (particularly disassembly).
1264 * You can now use a literal value 'unlimited' for options that
1265 interpret 0 or -1 as meaning "unlimited". E.g., "set
1266 trace-buffer-size unlimited" is now an alias for "set
1267 trace-buffer-size -1" and "set height unlimited" is now an alias for
1270 * The "set debug symtab-create" debugging option of GDB has been changed to
1271 accept a verbosity level. 0 means "off", 1 provides basic debugging
1272 output, and values of 2 or greater provides more verbose output.
1274 * New command-line options
1276 Display the details of GDB configure-time options.
1278 * The command 'tsave' can now support new option '-ctf' to save trace
1279 buffer in Common Trace Format.
1281 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1284 * GDB now implements the the C++ 'typeid' operator.
1286 * The new convenience variable $_exception holds the exception being
1287 thrown or caught at an exception-related catchpoint.
1289 * The exception-related catchpoints, like "catch throw", now accept a
1290 regular expression which can be used to filter exceptions by type.
1292 * The new convenience variable $_exitsignal is automatically set to
1293 the terminating signal number when the program being debugged dies
1294 due to an uncaught signal.
1298 ** All MI commands now accept an optional "--language" option.
1299 Support for this feature can be verified by using the "-list-features"
1300 command, which should contain "language-option".
1302 ** The new command -info-gdb-mi-command allows the user to determine
1303 whether a GDB/MI command is supported or not.
1305 ** The "^error" result record returned when trying to execute an undefined
1306 GDB/MI command now provides a variable named "code" whose content is the
1307 "undefined-command" error code. Support for this feature can be verified
1308 by using the "-list-features" command, which should contain
1309 "undefined-command-error-code".
1311 ** The -trace-save MI command can optionally save trace buffer in Common
1314 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1316 ** The command -data-list-register-values now accepts an optional
1317 "--skip-unavailable" option. When used, only the available registers
1320 ** The new command -trace-frame-collected dumps collected variables,
1321 computed expressions, tvars, memory and registers in a traceframe.
1323 ** The commands -stack-list-locals, -stack-list-arguments and
1324 -stack-list-variables now accept an option "--skip-unavailable".
1325 When used, only the available locals or arguments are displayed.
1327 ** The -exec-run command now accepts an optional "--start" option.
1328 When used, the command follows the same semantics as the "start"
1329 command, stopping the program's execution at the start of its
1330 main subprogram. Support for this feature can be verified using
1331 the "-list-features" command, which should contain
1332 "exec-run-start-option".
1334 ** The new commands -catch-assert and -catch-exceptions insert
1335 catchpoints stopping the program when Ada exceptions are raised.
1337 ** The new command -info-ada-exceptions provides the equivalent of
1338 the new "info exceptions" command.
1340 * New system-wide configuration scripts
1341 A GDB installation now provides scripts suitable for use as system-wide
1342 configuration scripts for the following systems:
1346 * GDB now supports target-assigned range stepping with remote targets.
1347 This improves the performance of stepping source lines by reducing
1348 the number of control packets from/to GDB. See "New remote packets"
1351 * GDB now understands the element 'tvar' in the XML traceframe info.
1352 It has the id of the collected trace state variables.
1354 * On S/390 targets that provide the transactional-execution feature,
1355 the program interruption transaction diagnostic block (TDB) is now
1356 represented as a number of additional "registers" in GDB.
1358 * New remote packets
1362 The vCont packet supports a new 'r' action, that tells the remote
1363 stub to step through an address range itself, without GDB
1364 involvemement at each single-step.
1366 qXfer:libraries-svr4:read's annex
1367 The previously unused annex of the qXfer:libraries-svr4:read packet
1368 is now used to support passing an argument list. The remote stub
1369 reports support for this argument list to GDB's qSupported query.
1370 The defined arguments are "start" and "prev", used to reduce work
1371 necessary for library list updating, resulting in significant
1374 * New features in the GDB remote stub, GDBserver
1376 ** GDBserver now supports target-assisted range stepping. Currently
1377 enabled on x86/x86_64 GNU/Linux targets.
1379 ** GDBserver now adds element 'tvar' in the XML in the reply to
1380 'qXfer:traceframe-info:read'. It has the id of the collected
1381 trace state variables.
1383 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1386 * New 'z' formatter for printing and examining memory, this displays the
1387 value as hexadecimal zero padded on the left to the size of the type.
1389 * GDB can now use Windows x64 unwinding data.
1391 * The "set remotebaud" command has been replaced by "set serial baud".
1392 Similarly, "show remotebaud" has been replaced by "show serial baud".
1393 The "set remotebaud" and "show remotebaud" commands are still available
1394 to provide backward compatibility with older versions of GDB.
1396 *** Changes in GDB 7.6
1398 * Target record has been renamed to record-full.
1399 Record/replay is now enabled with the "record full" command.
1400 This also affects settings that are associated with full record/replay
1401 that have been moved from "set/show record" to "set/show record full":
1403 set|show record full insn-number-max
1404 set|show record full stop-at-limit
1405 set|show record full memory-query
1407 * A new record target "record-btrace" has been added. The new target
1408 uses hardware support to record the control-flow of a process. It
1409 does not support replaying the execution, but it implements the
1410 below new commands for investigating the recorded execution log.
1411 This new recording method can be enabled using:
1415 The "record-btrace" target is only available on Intel Atom processors
1416 and requires a Linux kernel 2.6.32 or later.
1418 * Two new commands have been added for record/replay to give information
1419 about the recorded execution without having to replay the execution.
1420 The commands are only supported by "record btrace".
1422 record instruction-history prints the execution history at
1423 instruction granularity
1425 record function-call-history prints the execution history at
1426 function granularity
1428 * New native configurations
1430 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1431 FreeBSD/powerpc powerpc*-*-freebsd
1432 x86_64/Cygwin x86_64-*-cygwin*
1433 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1437 ARM AArch64 aarch64*-*-elf
1438 ARM AArch64 GNU/Linux aarch64*-*-linux
1439 Lynx 178 PowerPC powerpc-*-lynx*178
1440 x86_64/Cygwin x86_64-*-cygwin*
1441 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1443 * If the configured location of system.gdbinit file (as given by the
1444 --with-system-gdbinit option at configure time) is in the
1445 data-directory (as specified by --with-gdb-datadir at configure
1446 time) or in one of its subdirectories, then GDB will look for the
1447 system-wide init file in the directory specified by the
1448 --data-directory command-line option.
1450 * New command line options:
1452 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1453 other initialization files, unlike -nx which disables all of them.
1455 * Removed command line options
1457 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1460 * The 'ptype' and 'whatis' commands now accept an argument to control
1463 * 'info proc' now works on some core files.
1467 ** Vectors can be created with gdb.Type.vector.
1469 ** Python's atexit.register now works in GDB.
1471 ** Types can be pretty-printed via a Python API.
1473 ** Python 3 is now supported (in addition to Python 2.4 or later)
1475 ** New class gdb.Architecture exposes GDB's internal representation
1476 of architecture in the Python API.
1478 ** New method Frame.architecture returns the gdb.Architecture object
1479 corresponding to the frame's architecture.
1481 * New Python-based convenience functions:
1483 ** $_memeq(buf1, buf2, length)
1484 ** $_streq(str1, str2)
1486 ** $_regex(str, regex)
1488 * The 'cd' command now defaults to using '~' (the home directory) if not
1491 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1492 default for GCC since November 2000.
1494 * The command 'forward-search' can now be abbreviated as 'fo'.
1496 * The command 'info tracepoints' can now display 'installed on target'
1497 or 'not installed on target' for each non-pending location of tracepoint.
1499 * New configure options
1501 --enable-libmcheck/--disable-libmcheck
1502 By default, development versions are built with -lmcheck on hosts
1503 that support it, in order to help track memory corruption issues.
1504 Release versions, on the other hand, are built without -lmcheck
1505 by default. The --enable-libmcheck/--disable-libmcheck configure
1506 options allow the user to override that default.
1507 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1508 This configure option allows the user to build GDB with
1509 libbabeltrace using which GDB can read Common Trace Format data.
1511 * New commands (for set/show, see "New options" below)
1514 Catch signals. This is similar to "handle", but allows commands and
1515 conditions to be attached.
1518 List the BFDs known to GDB.
1520 python-interactive [command]
1522 Start a Python interactive prompt, or evaluate the optional command
1523 and print the result of expressions.
1526 "py" is a new alias for "python".
1528 enable type-printer [name]...
1529 disable type-printer [name]...
1530 Enable or disable type printers.
1534 ** For the Renesas Super-H architecture, the "regs" command has been removed
1535 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1540 set print type methods (on|off)
1541 show print type methods
1542 Control whether method declarations are displayed by "ptype".
1543 The default is to show them.
1545 set print type typedefs (on|off)
1546 show print type typedefs
1547 Control whether typedef definitions are displayed by "ptype".
1548 The default is to show them.
1550 set filename-display basename|relative|absolute
1551 show filename-display
1552 Control the way in which filenames is displayed.
1553 The default is "relative", which preserves previous behavior.
1555 set trace-buffer-size
1556 show trace-buffer-size
1557 Request target to change the size of trace buffer.
1559 set remote trace-buffer-size-packet auto|on|off
1560 show remote trace-buffer-size-packet
1561 Control the use of the remote protocol `QTBuffer:size' packet.
1565 Control display of debugging messages related to ARM AArch64.
1568 set debug coff-pe-read
1569 show debug coff-pe-read
1570 Control display of debugging messages related to reading of COFF/PE
1575 Control display of debugging messages related to Mach-O symbols
1578 set debug notification
1579 show debug notification
1580 Control display of debugging info for async remote notification.
1584 ** Command parameter changes are now notified using new async record
1585 "=cmd-param-changed".
1586 ** Trace frame changes caused by command "tfind" are now notified using
1587 new async record "=traceframe-changed".
1588 ** The creation, deletion and modification of trace state variables
1589 are now notified using new async records "=tsv-created",
1590 "=tsv-deleted" and "=tsv-modified".
1591 ** The start and stop of process record are now notified using new
1592 async record "=record-started" and "=record-stopped".
1593 ** Memory changes are now notified using new async record
1595 ** The data-disassemble command response will include a "fullname" field
1596 containing the absolute file name when source has been requested.
1597 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1598 command, to allow pattern filling of memory areas.
1599 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1600 library load/unload events.
1601 ** The response to breakpoint commands and breakpoint async records
1602 includes an "installed" field containing a boolean state about each
1603 non-pending tracepoint location is whether installed on target or not.
1604 ** Output of the "-trace-status" command includes a "trace-file" field
1605 containing the name of the trace file being examined. This field is
1606 optional, and only present when examining a trace file.
1607 ** The "fullname" field is now always present along with the "file" field,
1608 even if the file cannot be found by GDB.
1610 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1611 You must have the LZMA library available when configuring GDB for this
1612 feature to be enabled. For more information, see:
1613 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1615 * New remote packets
1618 Set the size of trace buffer. The remote stub reports support for this
1619 packet to gdb's qSupported query.
1622 Enable Branch Trace Store (BTS)-based branch tracing for the current
1623 thread. The remote stub reports support for this packet to gdb's
1627 Disable branch tracing for the current thread. The remote stub reports
1628 support for this packet to gdb's qSupported query.
1631 Read the traced branches for the current thread. The remote stub
1632 reports support for this packet to gdb's qSupported query.
1634 *** Changes in GDB 7.5
1636 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1637 for more x32 ABI info.
1639 * GDB now supports access to MIPS DSP registers on Linux targets.
1641 * GDB now supports debugging microMIPS binaries.
1643 * The "info os" command on GNU/Linux can now display information on
1644 several new classes of objects managed by the operating system:
1645 "info os procgroups" lists process groups
1646 "info os files" lists file descriptors
1647 "info os sockets" lists internet-domain sockets
1648 "info os shm" lists shared-memory regions
1649 "info os semaphores" lists semaphores
1650 "info os msg" lists message queues
1651 "info os modules" lists loaded kernel modules
1653 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1654 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1655 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1656 options and inspect the probe arguments using the new $_probe_arg family
1657 of convenience variables. You can obtain more information about SystemTap
1658 in <http://sourceware.org/systemtap/>.
1660 * GDB now supports reversible debugging on ARM, it allows you to
1661 debug basic ARM and THUMB instructions, and provides
1662 record/replay support.
1664 * The option "symbol-reloading" has been deleted as it is no longer used.
1668 ** GDB commands implemented in Python can now be put in command class
1671 ** The "maint set python print-stack on|off" is now deleted.
1673 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1674 apply "flag enum"-style pretty-printing to any enum.
1676 ** gdb.lookup_symbol can now work when there is no current frame.
1678 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1679 the source at which the symbol was defined.
1681 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1682 method 'value'. The former indicates whether the symbol needs a
1683 frame in order to compute its value, and the latter computes the
1686 ** A new method 'referenced_value' on gdb.Value objects which can
1687 dereference pointer as well as C++ reference values.
1689 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1690 which return the global and static blocks (as gdb.Block objects),
1691 of the underlying symbol table, respectively.
1693 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1694 object associated with a PC value.
1696 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1697 of the address range occupied by code for the current source line.
1699 * Go language support.
1700 GDB now supports debugging programs written in the Go programming
1703 * GDBserver now supports stdio connections.
1704 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1706 * The binary "gdbtui" can no longer be built or installed.
1707 Use "gdb -tui" instead.
1709 * GDB will now print "flag" enums specially. A flag enum is one where
1710 all the enumerator values have no bits in common when pairwise
1711 "and"ed. When printing a value whose type is a flag enum, GDB will
1712 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1713 (gdb) print (enum E) 3
1716 * The filename part of a linespec will now match trailing components
1717 of a source file name. For example, "break gcc/expr.c:1000" will
1718 now set a breakpoint in build/gcc/expr.c, but not
1719 build/libcpp/expr.c.
1721 * The "info proc" and "generate-core-file" commands will now also
1722 work on remote targets connected to GDBserver on Linux.
1724 * The command "info catch" has been removed. It has been disabled
1725 since December 2007.
1727 * The "catch exception" and "catch assert" commands now accept
1728 a condition at the end of the command, much like the "break"
1729 command does. For instance:
1731 (gdb) catch exception Constraint_Error if Barrier = True
1733 Previously, it was possible to add a condition to such catchpoints,
1734 but it had to be done as a second step, after the catchpoint had been
1735 created, using the "condition" command.
1737 * The "info static-tracepoint-marker" command will now also work on
1738 native Linux targets with in-process agent.
1740 * GDB can now set breakpoints on inlined functions.
1742 * The .gdb_index section has been updated to include symbols for
1743 inlined functions. GDB will ignore older .gdb_index sections by
1744 default, which could cause symbol files to be loaded more slowly
1745 until their .gdb_index sections can be recreated. The new command
1746 "set use-deprecated-index-sections on" will cause GDB to use any older
1747 .gdb_index sections it finds. This will restore performance, but the
1748 ability to set breakpoints on inlined functions will be lost in symbol
1749 files with older .gdb_index sections.
1751 The .gdb_index section has also been updated to record more information
1752 about each symbol. This speeds up the "info variables", "info functions"
1753 and "info types" commands when used with programs having the .gdb_index
1754 section, as well as speeding up debugging with shared libraries using
1755 the .gdb_index section.
1757 * Ada support for GDB/MI Variable Objects has been added.
1759 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1764 ** New command -info-os is the MI equivalent of "info os".
1766 ** Output logs ("set logging" and related) now include MI output.
1770 ** "set use-deprecated-index-sections on|off"
1771 "show use-deprecated-index-sections on|off"
1772 Controls the use of deprecated .gdb_index sections.
1774 ** "catch load" and "catch unload" can be used to stop when a shared
1775 library is loaded or unloaded, respectively.
1777 ** "enable count" can be used to auto-disable a breakpoint after
1780 ** "info vtbl" can be used to show the virtual method tables for
1781 C++ and Java objects.
1783 ** "explore" and its sub commands "explore value" and "explore type"
1784 can be used to recursively explore values and types of
1785 expressions. These commands are available only if GDB is
1786 configured with '--with-python'.
1788 ** "info auto-load" shows status of all kinds of auto-loaded files,
1789 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1790 sequences of commands files, "info auto-load python-scripts"
1791 shows status of auto-loading Python script files,
1792 "info auto-load local-gdbinit" shows status of loading init file
1793 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1794 status of inferior specific thread debugging shared library loading.
1796 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1797 and "show auto-load-scripts" commands have been deprecated, use their
1798 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1799 and "show auto-load python-scripts" counterparts instead.
1801 ** "dprintf location,format,args..." creates a dynamic printf, which
1802 is basically a breakpoint that does a printf and immediately
1803 resumes your program's execution, so it is like a printf that you
1804 can insert dynamically at runtime instead of at compiletime.
1806 ** "set print symbol"
1808 Controls whether GDB attempts to display the symbol, if any,
1809 corresponding to addresses it prints. This defaults to "on", but
1810 you can set it to "off" to restore GDB's previous behavior.
1812 * Deprecated commands
1814 ** For the Renesas Super-H architecture, the "regs" command has been
1815 deprecated, and "info all-registers" should be used instead.
1819 Renesas RL78 rl78-*-elf
1820 HP OpenVMS ia64 ia64-hp-openvms*
1822 * GDBserver supports evaluation of breakpoint conditions. When
1823 support is advertised by GDBserver, GDB may be told to send the
1824 breakpoint conditions in bytecode form to GDBserver. GDBserver
1825 will only report the breakpoint trigger to GDB when its condition
1830 set mips compression
1831 show mips compression
1832 Select the compressed ISA encoding used in functions that have no symbol
1833 information available. The encoding can be set to either of:
1836 and is updated automatically from ELF file flags if available.
1838 set breakpoint condition-evaluation
1839 show breakpoint condition-evaluation
1840 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1841 GDBserver ("target"). Default option "auto" chooses the most efficient
1843 This option can improve debugger efficiency depending on the speed of the
1847 Disable auto-loading globally.
1850 Show auto-loading setting of all kinds of auto-loaded files.
1852 set auto-load gdb-scripts on|off
1853 show auto-load gdb-scripts
1854 Control auto-loading of GDB canned sequences of commands files.
1856 set auto-load python-scripts on|off
1857 show auto-load python-scripts
1858 Control auto-loading of Python script files.
1860 set auto-load local-gdbinit on|off
1861 show auto-load local-gdbinit
1862 Control loading of init file (.gdbinit) from current directory.
1864 set auto-load libthread-db on|off
1865 show auto-load libthread-db
1866 Control auto-loading of inferior specific thread debugging shared library.
1868 set auto-load scripts-directory <dir1>[:<dir2>...]
1869 show auto-load scripts-directory
1870 Set a list of directories from which to load auto-loaded scripts.
1871 Automatically loaded Python scripts and GDB scripts are located in one
1872 of the directories listed by this option.
1873 The delimiter (':' above) may differ according to the host platform.
1875 set auto-load safe-path <dir1>[:<dir2>...]
1876 show auto-load safe-path
1877 Set a list of directories from which it is safe to auto-load files.
1878 The delimiter (':' above) may differ according to the host platform.
1880 set debug auto-load on|off
1881 show debug auto-load
1882 Control display of debugging info for auto-loading the files above.
1884 set dprintf-style gdb|call|agent
1886 Control the way in which a dynamic printf is performed; "gdb"
1887 requests a GDB printf command, while "call" causes dprintf to call a
1888 function in the inferior. "agent" requests that the target agent
1889 (such as GDBserver) do the printing.
1891 set dprintf-function <expr>
1892 show dprintf-function
1893 set dprintf-channel <expr>
1894 show dprintf-channel
1895 Set the function and optional first argument to the call when using
1896 the "call" style of dynamic printf.
1898 set disconnected-dprintf on|off
1899 show disconnected-dprintf
1900 Control whether agent-style dynamic printfs continue to be in effect
1901 after GDB disconnects.
1903 * New configure options
1905 --with-auto-load-dir
1906 Configure default value for the 'set auto-load scripts-directory'
1907 setting above. It defaults to '$debugdir:$datadir/auto-load',
1908 $debugdir representing global debugging info directories (available
1909 via 'show debug-file-directory') and $datadir representing GDB's data
1910 directory (available via 'show data-directory').
1912 --with-auto-load-safe-path
1913 Configure default value for the 'set auto-load safe-path' setting
1914 above. It defaults to the --with-auto-load-dir setting.
1916 --without-auto-load-safe-path
1917 Set 'set auto-load safe-path' to '/', effectively disabling this
1920 * New remote packets
1922 z0/z1 conditional breakpoints extension
1924 The z0/z1 breakpoint insertion packets have been extended to carry
1925 a list of conditional expressions over to the remote stub depending on the
1926 condition evaluation mode. The use of this extension can be controlled
1927 via the "set remote conditional-breakpoints-packet" command.
1931 Specify the signals which the remote stub may pass to the debugged
1932 program without GDB involvement.
1934 * New command line options
1936 --init-command=FILE, -ix Like --command, -x but execute it
1937 before loading inferior.
1938 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1939 execute it before loading inferior.
1941 *** Changes in GDB 7.4
1943 * GDB now handles ambiguous linespecs more consistently; the existing
1944 FILE:LINE support has been expanded to other types of linespecs. A
1945 breakpoint will now be set on all matching locations in all
1946 inferiors, and locations will be added or removed according to
1949 * GDB now allows you to skip uninteresting functions and files when
1950 stepping with the "skip function" and "skip file" commands.
1952 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1953 and "show remote hardware-watchpoint-length-limit". These allows to
1954 set or show the maximum length limit (in bytes) of a remote
1955 target hardware watchpoint.
1957 This allows e.g. to use "unlimited" hardware watchpoints with the
1958 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1959 watchpoints are slower than real hardware watchpoints but are
1960 significantly faster than gdb software watchpoints.
1964 ** The register_pretty_printer function in module gdb.printing now takes
1965 an optional `replace' argument. If True, the new printer replaces any
1968 ** The "maint set python print-stack on|off" command has been
1969 deprecated and will be deleted in GDB 7.5.
1970 A new command: "set python print-stack none|full|message" has
1971 replaced it. Additionally, the default for "print-stack" is
1972 now "message", which just prints the error message without
1975 ** A prompt substitution hook (prompt_hook) is now available to the
1978 ** A new Python module, gdb.prompt has been added to the GDB Python
1979 modules library. This module provides functionality for
1980 escape sequences in prompts (used by set/show
1981 extended-prompt). These escape sequences are replaced by their
1982 corresponding value.
1984 ** Python commands and convenience-functions located in
1985 'data-directory'/python/gdb/command and
1986 'data-directory'/python/gdb/function are now automatically loaded
1989 ** Blocks now provide four new attributes. global_block and
1990 static_block will return the global and static blocks
1991 respectively. is_static and is_global are boolean attributes
1992 that indicate if the block is one of those two types.
1994 ** Symbols now provide the "type" attribute, the type of the symbol.
1996 ** The "gdb.breakpoint" function has been deprecated in favor of
1999 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2000 of a function. This class is based on the "finish" command
2001 available in the CLI.
2003 ** Type objects for struct and union types now allow access to
2004 the fields using standard Python dictionary (mapping) methods.
2005 For example, "some_type['myfield']" now works, as does
2006 "some_type.items()".
2008 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2011 ** A new function, "deep_items" has been added to the gdb.types
2012 module in the GDB Python modules library. This function returns
2013 an iterator over the fields of a struct or union type. Unlike
2014 the standard Python "iteritems" method, it will recursively traverse
2015 any anonymous fields.
2019 ** "*stopped" events can report several new "reason"s, such as
2022 ** Breakpoint changes are now notified using new async records, like
2023 "=breakpoint-modified".
2025 ** New command -ada-task-info.
2027 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2028 $sdir specifies the default system locations of shared libraries.
2029 $pdir specifies the directory where the libpthread used by the application
2032 GDB no longer looks in $sdir and $pdir after it has searched the directories
2033 mentioned in libthread-db-search-path. If you want to search those
2034 directories, they must be specified in libthread-db-search-path.
2035 The default value of libthread-db-search-path on GNU/Linux and Solaris
2036 systems is now "$sdir:$pdir".
2038 $pdir is not supported by gdbserver, it is currently ignored.
2039 $sdir is supported by gdbserver.
2041 * New configure option --with-iconv-bin.
2042 When using the internationalization support like the one in the GNU C
2043 library, GDB will invoke the "iconv" program to get a list of supported
2044 character sets. If this program lives in a non-standard location, one can
2045 use this option to specify where to find it.
2047 * When natively debugging programs on PowerPC BookE processors running
2048 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2049 watchpoints, which specify a mask in addition to an address to watch.
2050 The mask specifies that some bits of an address (the bits which are
2051 reset in the mask) should be ignored when matching the address accessed
2052 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2053 section in the user manual for more details.
2055 * The new option --once causes GDBserver to stop listening for connections once
2056 the first connection is made. The listening port used by GDBserver will
2057 become available after that.
2059 * New commands "info macros" and "alias" have been added.
2061 * New function parameters suffix @entry specifies value of function parameter
2062 at the time the function got called. Entry values are available only since
2068 "!" is now an alias of the "shell" command.
2069 Note that no space is needed between "!" and SHELL COMMAND.
2073 watch EXPRESSION mask MASK_VALUE
2074 The watch command now supports the mask argument which allows creation
2075 of masked watchpoints, if the current architecture supports this feature.
2077 info auto-load-scripts [REGEXP]
2078 This command was formerly named "maintenance print section-scripts".
2079 It is now generally useful and is no longer a maintenance-only command.
2081 info macro [-all] [--] MACRO
2082 The info macro command has new options `-all' and `--'. The first for
2083 printing all definitions of a macro. The second for explicitly specifying
2084 the end of arguments and the beginning of the macro name in case the macro
2085 name starts with a hyphen.
2087 collect[/s] EXPRESSIONS
2088 The tracepoint collect command now takes an optional modifier "/s"
2089 that directs it to dereference pointer-to-character types and
2090 collect the bytes of memory up to a zero byte. The behavior is
2091 similar to what you see when you use the regular print command on a
2092 string. An optional integer following the "/s" sets a bound on the
2093 number of bytes that will be collected.
2096 The trace start command now interprets any supplied arguments as a
2097 note to be recorded with the trace run, with an effect similar to
2098 setting the variable trace-notes.
2101 The trace stop command now interprets any arguments as a note to be
2102 mentioned along with the tstatus report that the trace was stopped
2103 with a command. The effect is similar to setting the variable
2106 * Tracepoints can now be enabled and disabled at any time after a trace
2107 experiment has been started using the standard "enable" and "disable"
2108 commands. It is now possible to start a trace experiment with no enabled
2109 tracepoints; GDB will display a warning, but will allow the experiment to
2110 begin, assuming that tracepoints will be enabled as needed while the trace
2113 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2114 locations with 4-byte instructions, when they were previously
2115 limited to locations with instructions of 5 bytes or longer.
2119 set debug dwarf2-read
2120 show debug dwarf2-read
2121 Turns on or off display of debugging messages related to reading
2122 DWARF debug info. The default is off.
2124 set debug symtab-create
2125 show debug symtab-create
2126 Turns on or off display of debugging messages related to symbol table
2127 creation. The default is off.
2130 show extended-prompt
2131 Set the GDB prompt, and allow escape sequences to be inserted to
2132 display miscellaneous information (see 'help set extended-prompt'
2133 for the list of sequences). This prompt (and any information
2134 accessed through the escape sequences) is updated every time the
2135 prompt is displayed.
2137 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2138 show print entry-values
2139 Set printing of frame argument values at function entry. In some cases
2140 GDB can determine the value of function argument which was passed by the
2141 function caller, even if the value was modified inside the called function.
2143 set debug entry-values
2144 show debug entry-values
2145 Control display of debugging info for determining frame argument values at
2146 function entry and virtual tail call frames.
2148 set basenames-may-differ
2149 show basenames-may-differ
2150 Set whether a source file may have multiple base names.
2151 (A "base name" is the name of a file with the directory part removed.
2152 Example: The base name of "/home/user/hello.c" is "hello.c".)
2153 If set, GDB will canonicalize file names (e.g., expand symlinks)
2154 before comparing them. Canonicalization is an expensive operation,
2155 but it allows the same file be known by more than one base name.
2156 If not set (the default), all source files are assumed to have just
2157 one base name, and gdb will do file name comparisons more efficiently.
2163 Set a user name and notes for the current and any future trace runs.
2164 This is useful for long-running and/or disconnected traces, to
2165 inform others (or yourself) as to who is running the trace, supply
2166 contact information, or otherwise explain what is going on.
2168 set trace-stop-notes
2169 show trace-stop-notes
2170 Set a note attached to the trace run, that is displayed when the
2171 trace has been stopped by a tstop command. This is useful for
2172 instance as an explanation, if you are stopping a trace run that was
2173 started by someone else.
2175 * New remote packets
2179 Dynamically enable a tracepoint in a started trace experiment.
2183 Dynamically disable a tracepoint in a started trace experiment.
2187 Set the user and notes of the trace run.
2191 Query the current status of a tracepoint.
2195 Query the minimum length of instruction at which a fast tracepoint may
2198 * Dcache size (number of lines) and line-size are now runtime-configurable
2199 via "set dcache line" and "set dcache line-size" commands.
2203 Texas Instruments TMS320C6x tic6x-*-*
2207 Renesas RL78 rl78-*-elf
2209 *** Changes in GDB 7.3.1
2211 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2213 *** Changes in GDB 7.3
2215 * GDB has a new command: "thread find [REGEXP]".
2216 It finds the thread id whose name, target id, or thread extra info
2217 matches the given regular expression.
2219 * The "catch syscall" command now works on mips*-linux* targets.
2221 * The -data-disassemble MI command now supports modes 2 and 3 for
2222 dumping the instruction opcodes.
2224 * New command line options
2226 -data-directory DIR Specify DIR as the "data-directory".
2227 This is mostly for testing purposes.
2229 * The "maint set python auto-load on|off" command has been renamed to
2230 "set auto-load-scripts on|off".
2232 * GDB has a new command: "set directories".
2233 It is like the "dir" command except that it replaces the
2234 source path list instead of augmenting it.
2236 * GDB now understands thread names.
2238 On GNU/Linux, "info threads" will display the thread name as set by
2239 prctl or pthread_setname_np.
2241 There is also a new command, "thread name", which can be used to
2242 assign a name internally for GDB to display.
2245 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2246 has been integrated into GDB.
2250 ** The function gdb.Write now accepts an optional keyword 'stream'.
2251 This keyword, when provided, will direct the output to either
2252 stdout, stderr, or GDB's logging output.
2254 ** Parameters can now be be sub-classed in Python, and in particular
2255 you may implement the get_set_doc and get_show_doc functions.
2256 This improves how Parameter set/show documentation is processed
2257 and allows for more dynamic content.
2259 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2260 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2261 have an is_valid method.
2263 ** Breakpoints can now be sub-classed in Python, and in particular
2264 you may implement a 'stop' function that is executed each time
2265 the inferior reaches that breakpoint.
2267 ** New function gdb.lookup_global_symbol looks up a global symbol.
2269 ** GDB values in Python are now callable if the value represents a
2270 function. For example, if 'some_value' represents a function that
2271 takes two integer parameters and returns a value, you can call
2272 that function like so:
2274 result = some_value (10,20)
2276 ** Module gdb.types has been added.
2277 It contains a collection of utilities for working with gdb.Types objects:
2278 get_basic_type, has_field, make_enum_dict.
2280 ** Module gdb.printing has been added.
2281 It contains utilities for writing and registering pretty-printers.
2282 New classes: PrettyPrinter, SubPrettyPrinter,
2283 RegexpCollectionPrettyPrinter.
2284 New function: register_pretty_printer.
2286 ** New commands "info pretty-printers", "enable pretty-printer" and
2287 "disable pretty-printer" have been added.
2289 ** gdb.parameter("directories") is now available.
2291 ** New function gdb.newest_frame returns the newest frame in the
2294 ** The gdb.InferiorThread class has a new "name" attribute. This
2295 holds the thread's name.
2297 ** Python Support for Inferior events.
2298 Python scripts can add observers to be notified of events
2299 occurring in the process being debugged.
2300 The following events are currently supported:
2301 - gdb.events.cont Continue event.
2302 - gdb.events.exited Inferior exited event.
2303 - gdb.events.stop Signal received, and Breakpoint hit events.
2307 ** GDB now puts template parameters in scope when debugging in an
2308 instantiation. For example, if you have:
2310 template<int X> int func (void) { return X; }
2312 then if you step into func<5>, "print X" will show "5". This
2313 feature requires proper debuginfo support from the compiler; it
2314 was added to GCC 4.5.
2316 ** The motion commands "next", "finish", "until", and "advance" now
2317 work better when exceptions are thrown. In particular, GDB will
2318 no longer lose control of the inferior; instead, the GDB will
2319 stop the inferior at the point at which the exception is caught.
2320 This functionality requires a change in the exception handling
2321 code that was introduced in GCC 4.5.
2323 * GDB now follows GCC's rules on accessing volatile objects when
2324 reading or writing target state during expression evaluation.
2325 One notable difference to prior behavior is that "print x = 0"
2326 no longer generates a read of x; the value of the assignment is
2327 now always taken directly from the value being assigned.
2329 * GDB now has some support for using labels in the program's source in
2330 linespecs. For instance, you can use "advance label" to continue
2331 execution to a label.
2333 * GDB now has support for reading and writing a new .gdb_index
2334 section. This section holds a fast index of DWARF debugging
2335 information and can be used to greatly speed up GDB startup and
2336 operation. See the documentation for `save gdb-index' for details.
2338 * The "watch" command now accepts an optional "-location" argument.
2339 When used, this causes GDB to watch the memory referred to by the
2340 expression. Such a watchpoint is never deleted due to it going out
2343 * GDB now supports thread debugging of core dumps on GNU/Linux.
2345 GDB now activates thread debugging using the libthread_db library
2346 when debugging GNU/Linux core dumps, similarly to when debugging
2347 live processes. As a result, when debugging a core dump file, GDB
2348 is now able to display pthread_t ids of threads. For example, "info
2349 threads" shows the same output as when debugging the process when it
2350 was live. In earlier releases, you'd see something like this:
2353 * 1 LWP 6780 main () at main.c:10
2355 While now you see this:
2358 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2360 It is also now possible to inspect TLS variables when debugging core
2363 When debugging a core dump generated on a machine other than the one
2364 used to run GDB, you may need to point GDB at the correct
2365 libthread_db library with the "set libthread-db-search-path"
2366 command. See the user manual for more details on this command.
2368 * When natively debugging programs on PowerPC BookE processors running
2369 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2370 which stop execution of the inferior whenever it executes an instruction
2371 at any address within the specified range. See the "PowerPC Embedded"
2372 section in the user manual for more details.
2374 * New features in the GDB remote stub, GDBserver
2376 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2377 and i686 LynxOS (version 5.x).
2379 ** GDBserver is now supported on Blackfin Linux.
2381 * New native configurations
2383 ia64 HP-UX ia64-*-hpux*
2387 Analog Devices, Inc. Blackfin Processor bfin-*
2389 * Ada task switching is now supported on sparc-elf targets when
2390 debugging a program using the Ravenscar Profile. For more information,
2391 see the "Tasking Support when using the Ravenscar Profile" section
2392 in the GDB user manual.
2394 * Guile support was removed.
2396 * New features in the GNU simulator
2398 ** The --map-info flag lists all known core mappings.
2400 ** CFI flashes may be simulated via the "cfi" device.
2402 *** Changes in GDB 7.2
2404 * Shared library support for remote targets by default
2406 When GDB is configured for a generic, non-OS specific target, like
2407 for example, --target=arm-eabi or one of the many *-*-elf targets,
2408 GDB now queries remote stubs for loaded shared libraries using the
2409 `qXfer:libraries:read' packet. Previously, shared library support
2410 was always disabled for such configurations.
2414 ** Argument Dependent Lookup (ADL)
2416 In C++ ADL lookup directs function search to the namespaces of its
2417 arguments even if the namespace has not been imported.
2427 Here the compiler will search for `foo' in the namespace of 'b'
2428 and find A::foo. GDB now supports this. This construct is commonly
2429 used in the Standard Template Library for operators.
2431 ** Improved User Defined Operator Support
2433 In addition to member operators, GDB now supports lookup of operators
2434 defined in a namespace and imported with a `using' directive, operators
2435 defined in the global scope, operators imported implicitly from an
2436 anonymous namespace, and the ADL operators mentioned in the previous
2438 GDB now also supports proper overload resolution for all the previously
2439 mentioned flavors of operators.
2441 ** static const class members
2443 Printing of static const class members that are initialized in the
2444 class definition has been fixed.
2446 * Windows Thread Information Block access.
2448 On Windows targets, GDB now supports displaying the Windows Thread
2449 Information Block (TIB) structure. This structure is visible either
2450 by using the new command `info w32 thread-information-block' or, by
2451 dereferencing the new convenience variable named `$_tlb', a
2452 thread-specific pointer to the TIB. This feature is also supported
2453 when remote debugging using GDBserver.
2455 * Static tracepoints
2457 Static tracepoints are calls in the user program into a tracing
2458 library. One such library is a port of the LTTng kernel tracer to
2459 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2460 When debugging with GDBserver, GDB now supports combining the GDB
2461 tracepoint machinery with such libraries. For example: the user can
2462 use GDB to probe a static tracepoint marker (a call from the user
2463 program into the tracing library) with the new "strace" command (see
2464 "New commands" below). This creates a "static tracepoint" in the
2465 breakpoint list, that can be manipulated with the same feature set
2466 as fast and regular tracepoints. E.g., collect registers, local and
2467 global variables, collect trace state variables, and define
2468 tracepoint conditions. In addition, the user can collect extra
2469 static tracepoint marker specific data, by collecting the new
2470 $_sdata internal variable. When analyzing the trace buffer, you can
2471 inspect $_sdata like any other variable available to GDB. For more
2472 information, see the "Tracepoints" chapter in GDB user manual. New
2473 remote packets have been defined to support static tracepoints, see
2474 the "New remote packets" section below.
2476 * Better reconstruction of tracepoints after disconnected tracing
2478 GDB will attempt to download the original source form of tracepoint
2479 definitions when starting a trace run, and then will upload these
2480 upon reconnection to the target, resulting in a more accurate
2481 reconstruction of the tracepoints that are in use on the target.
2485 You can now exercise direct control over the ways that GDB can
2486 affect your program. For instance, you can disallow the setting of
2487 breakpoints, so that the program can run continuously (assuming
2488 non-stop mode). In addition, the "observer" variable is available
2489 to switch all of the different controls; in observer mode, GDB
2490 cannot affect the target's behavior at all, which is useful for
2491 tasks like diagnosing live systems in the field.
2493 * The new convenience variable $_thread holds the number of the
2496 * New remote packets
2500 Return the address of the Windows Thread Information Block of a given thread.
2504 In response to several of the tracepoint packets, the target may now
2505 also respond with a number of intermediate `qRelocInsn' request
2506 packets before the final result packet, to have GDB handle
2507 relocating an instruction to execute at a different address. This
2508 is particularly useful for stubs that support fast tracepoints. GDB
2509 reports support for this feature in the qSupported packet.
2513 List static tracepoint markers in the target program.
2517 List static tracepoint markers at a given address in the target
2520 qXfer:statictrace:read
2522 Read the static trace data collected (by a `collect $_sdata'
2523 tracepoint action). The remote stub reports support for this packet
2524 to gdb's qSupported query.
2528 Send the current settings of GDB's permission flags.
2532 Send part of the source (textual) form of a tracepoint definition,
2533 which includes location, conditional, and action list.
2535 * The source command now accepts a -s option to force searching for the
2536 script in the source search path even if the script name specifies
2539 * New features in the GDB remote stub, GDBserver
2541 - GDBserver now support tracepoints (including fast tracepoints, and
2542 static tracepoints). The feature is currently supported by the
2543 i386-linux and amd64-linux builds. See the "Tracepoints support
2544 in gdbserver" section in the manual for more information.
2546 GDBserver JIT compiles the tracepoint's conditional agent
2547 expression bytecode into native code whenever possible for low
2548 overhead dynamic tracepoints conditionals. For such tracepoints,
2549 an expression that examines program state is evaluated when the
2550 tracepoint is reached, in order to determine whether to capture
2551 trace data. If the condition is simple and false, processing the
2552 tracepoint finishes very quickly and no data is gathered.
2554 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2555 for static tracepoints support.
2557 - GDBserver now supports x86_64 Windows 64-bit debugging.
2559 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2560 it understands register description.
2562 * The --batch flag now disables pagination and queries.
2564 * X86 general purpose registers
2566 GDB now supports reading/writing byte, word and double-word x86
2567 general purpose registers directly. This means you can use, say,
2568 $ah or $ax to refer, respectively, to the byte register AH and
2569 16-bit word register AX that are actually portions of the 32-bit
2570 register EAX or 64-bit register RAX.
2572 * The `commands' command now accepts a range of breakpoints to modify.
2573 A plain `commands' following a command that creates multiple
2574 breakpoints affects all the breakpoints set by that command. This
2575 applies to breakpoints set by `rbreak', and also applies when a
2576 single `break' command creates multiple breakpoints (e.g.,
2577 breakpoints on overloaded c++ functions).
2579 * The `rbreak' command now accepts a filename specification as part of
2580 its argument, limiting the functions selected by the regex to those
2581 in the specified file.
2583 * Support for remote debugging Windows and SymbianOS shared libraries
2584 from Unix hosts has been improved. Non Windows GDB builds now can
2585 understand target reported file names that follow MS-DOS based file
2586 system semantics, such as file names that include drive letters and
2587 use the backslash character as directory separator. This makes it
2588 possible to transparently use the "set sysroot" and "set
2589 solib-search-path" on Unix hosts to point as host copies of the
2590 target's shared libraries. See the new command "set
2591 target-file-system-kind" described below, and the "Commands to
2592 specify files" section in the user manual for more information.
2596 eval template, expressions...
2597 Convert the values of one or more expressions under the control
2598 of the string template to a command line, and call it.
2600 set target-file-system-kind unix|dos-based|auto
2601 show target-file-system-kind
2602 Set or show the assumed file system kind for target reported file
2605 save breakpoints <filename>
2606 Save all current breakpoint definitions to a file suitable for use
2607 in a later debugging session. To read the saved breakpoint
2608 definitions, use the `source' command.
2610 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2613 info static-tracepoint-markers
2614 Display information about static tracepoint markers in the target.
2616 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2617 Define a static tracepoint by probing a marker at the given
2618 function, line, address, or marker ID.
2622 Enable and disable observer mode.
2624 set may-write-registers on|off
2625 set may-write-memory on|off
2626 set may-insert-breakpoints on|off
2627 set may-insert-tracepoints on|off
2628 set may-insert-fast-tracepoints on|off
2629 set may-interrupt on|off
2630 Set individual permissions for GDB effects on the target. Note that
2631 some of these settings can have undesirable or surprising
2632 consequences, particularly when changed in the middle of a session.
2633 For instance, disabling the writing of memory can prevent
2634 breakpoints from being inserted, cause single-stepping to fail, or
2635 even crash your program, if you disable after breakpoints have been
2636 inserted. However, GDB should not crash.
2638 set record memory-query on|off
2639 show record memory-query
2640 Control whether to stop the inferior if memory changes caused
2641 by an instruction cannot be recorded.
2646 The disassemble command now supports "start,+length" form of two arguments.
2650 ** GDB now provides a new directory location, called the python directory,
2651 where Python scripts written for GDB can be installed. The location
2652 of that directory is <data-directory>/python, where <data-directory>
2653 is the GDB data directory. For more details, see section `Scripting
2654 GDB using Python' in the manual.
2656 ** The GDB Python API now has access to breakpoints, symbols, symbol
2657 tables, program spaces, inferiors, threads and frame's code blocks.
2658 Additionally, GDB Parameters can now be created from the API, and
2659 manipulated via set/show in the CLI.
2661 ** New functions gdb.target_charset, gdb.target_wide_charset,
2662 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2664 ** New exception gdb.GdbError.
2666 ** Pretty-printers are now also looked up in the current program space.
2668 ** Pretty-printers can now be individually enabled and disabled.
2670 ** GDB now looks for names of Python scripts to auto-load in a
2671 special section named `.debug_gdb_scripts', in addition to looking
2672 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2674 * Tracepoint actions were unified with breakpoint commands. In particular,
2675 there are no longer differences in "info break" output for breakpoints and
2676 tracepoints and the "commands" command can be used for both tracepoints and
2677 regular breakpoints.
2681 ARM Symbian arm*-*-symbianelf*
2683 * D language support.
2684 GDB now supports debugging programs written in the D programming
2687 * GDB now supports the extended ptrace interface for PowerPC which is
2688 available since Linux kernel version 2.6.34. This automatically enables
2689 any hardware breakpoints and additional hardware watchpoints available in
2690 the processor. The old ptrace interface exposes just one hardware
2691 watchpoint and no hardware breakpoints.
2693 * GDB is now able to use the Data Value Compare (DVC) register available on
2694 embedded PowerPC processors to implement in hardware simple watchpoint
2695 conditions of the form:
2697 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2699 This works in native GDB running on Linux kernels with the extended ptrace
2700 interface mentioned above.
2702 *** Changes in GDB 7.1
2706 ** Namespace Support
2708 GDB now supports importing of namespaces in C++. This enables the
2709 user to inspect variables from imported namespaces. Support for
2710 namepace aliasing has also been added. So, if a namespace is
2711 aliased in the current scope (e.g. namepace C=A; ) the user can
2712 print variables using the alias (e.g. (gdb) print C::x).
2716 All known bugs relating to the printing of virtual base class were
2717 fixed. It is now possible to call overloaded static methods using a
2722 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2723 and reinterpret_cast<> are now handled by the C++ expression parser.
2727 Xilinx MicroBlaze microblaze-*-*
2732 Xilinx MicroBlaze microblaze
2735 * Multi-program debugging.
2737 GDB now has support for multi-program (a.k.a. multi-executable or
2738 multi-exec) debugging. This allows for debugging multiple inferiors
2739 simultaneously each running a different program under the same GDB
2740 session. See "Debugging Multiple Inferiors and Programs" in the
2741 manual for more information. This implied some user visible changes
2742 in the multi-inferior support. For example, "info inferiors" now
2743 lists inferiors that are not running yet or that have exited
2744 already. See also "New commands" and "New options" below.
2746 * New tracing features
2748 GDB's tracepoint facility now includes several new features:
2750 ** Trace state variables
2752 GDB tracepoints now include support for trace state variables, which
2753 are variables managed by the target agent during a tracing
2754 experiment. They are useful for tracepoints that trigger each
2755 other, so for instance one tracepoint can count hits in a variable,
2756 and then a second tracepoint has a condition that is true when the
2757 count reaches a particular value. Trace state variables share the
2758 $-syntax of GDB convenience variables, and can appear in both
2759 tracepoint actions and condition expressions. Use the "tvariable"
2760 command to create, and "info tvariables" to view; see "Trace State
2761 Variables" in the manual for more detail.
2765 GDB now includes an option for defining fast tracepoints, which
2766 targets may implement more efficiently, such as by installing a jump
2767 into the target agent rather than a trap instruction. The resulting
2768 speedup can be by two orders of magnitude or more, although the
2769 tradeoff is that some program locations on some target architectures
2770 might not allow fast tracepoint installation, for instance if the
2771 instruction to be replaced is shorter than the jump. To request a
2772 fast tracepoint, use the "ftrace" command, with syntax identical to
2773 the regular trace command.
2775 ** Disconnected tracing
2777 It is now possible to detach GDB from the target while it is running
2778 a trace experiment, then reconnect later to see how the experiment
2779 is going. In addition, a new variable disconnected-tracing lets you
2780 tell the target agent whether to continue running a trace if the
2781 connection is lost unexpectedly.
2785 GDB now has the ability to save the trace buffer into a file, and
2786 then use that file as a target, similarly to you can do with
2787 corefiles. You can select trace frames, print data that was
2788 collected in them, and use tstatus to display the state of the
2789 tracing run at the moment that it was saved. To create a trace
2790 file, use "tsave <filename>", and to use it, do "target tfile
2793 ** Circular trace buffer
2795 You can ask the target agent to handle the trace buffer as a
2796 circular buffer, discarding the oldest trace frames to make room for
2797 newer ones, by setting circular-trace-buffer to on. This feature may
2798 not be available for all target agents.
2803 The disassemble command, when invoked with two arguments, now requires
2804 the arguments to be comma-separated.
2807 The info variables command now displays variable definitions. Files
2808 which only declare a variable are not shown.
2811 The source command is now capable of sourcing Python scripts.
2812 This feature is dependent on the debugger being build with Python
2815 Related to this enhancement is also the introduction of a new command
2816 "set script-extension" (see below).
2818 * New commands (for set/show, see "New options" below)
2820 record save [<FILENAME>]
2821 Save a file (in core file format) containing the process record
2822 execution log for replay debugging at a later time.
2824 record restore <FILENAME>
2825 Restore the process record execution log that was saved at an
2826 earlier time, for replay debugging.
2828 add-inferior [-copies <N>] [-exec <FILENAME>]
2831 clone-inferior [-copies <N>] [ID]
2832 Make a new inferior ready to execute the same program another
2833 inferior has loaded.
2838 maint info program-spaces
2839 List the program spaces loaded into GDB.
2841 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2842 show remote interrupt-sequence
2843 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2844 as the sequence to the remote target in order to interrupt the execution.
2845 Ctrl-C is a default. Some system prefers BREAK which is high level of
2846 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2847 Magic SysRq g. It is BREAK signal and character 'g'.
2849 set remote interrupt-on-connect [on | off]
2850 show remote interrupt-on-connect
2851 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2852 remote target when gdb connects to it. This is needed when you debug
2855 set remotebreak [on | off]
2857 Deprecated. Use "set/show remote interrupt-sequence" instead.
2859 tvariable $NAME [ = EXP ]
2860 Create or modify a trace state variable.
2863 List trace state variables and their values.
2865 delete tvariable $NAME ...
2866 Delete one or more trace state variables.
2869 Evaluate the given expressions without collecting anything into the
2870 trace buffer. (Valid in tracepoint actions only.)
2872 ftrace FN / FILE:LINE / *ADDR
2873 Define a fast tracepoint at the given function, line, or address.
2875 * New expression syntax
2877 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2878 GDB now parses 0b101010 identically with 42.
2882 set follow-exec-mode new|same
2883 show follow-exec-mode
2884 Control whether GDB reuses the same inferior across an exec call or
2885 creates a new one. This is useful to be able to restart the old
2886 executable after the inferior having done an exec call.
2888 set default-collect EXPR, ...
2889 show default-collect
2890 Define a list of expressions to be collected at each tracepoint.
2891 This is a useful way to ensure essential items are not overlooked,
2892 such as registers or a critical global variable.
2894 set disconnected-tracing
2895 show disconnected-tracing
2896 If set to 1, the target is instructed to continue tracing if it
2897 loses its connection to GDB. If 0, the target is to stop tracing
2900 set circular-trace-buffer
2901 show circular-trace-buffer
2902 If set to on, the target is instructed to use a circular trace buffer
2903 and discard the oldest trace frames instead of stopping the trace due
2904 to a full trace buffer. If set to off, the trace stops when the buffer
2905 fills up. Some targets may not support this.
2907 set script-extension off|soft|strict
2908 show script-extension
2909 If set to "off", the debugger does not perform any script language
2910 recognition, and all sourced files are assumed to be GDB scripts.
2911 If set to "soft" (the default), files are sourced according to
2912 filename extension, falling back to GDB scripts if the first
2914 If set to "strict", files are sourced according to filename extension.
2916 set ada trust-PAD-over-XVS on|off
2917 show ada trust-PAD-over-XVS
2918 If off, activate a workaround against a bug in the debugging information
2919 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2920 the GCC sources for more information about the GNAT encoding and
2921 PAD types in particular). It is always safe to set this option to
2922 off, but this introduces a slight performance penalty. The default
2925 * Python API Improvements
2927 ** GDB provides the new class gdb.LazyString. This is useful in
2928 some pretty-printing cases. The new method gdb.Value.lazy_string
2929 provides a simple way to create objects of this type.
2931 ** The fields returned by gdb.Type.fields now have an
2932 `is_base_class' attribute.
2934 ** The new method gdb.Type.range returns the range of an array type.
2936 ** The new method gdb.parse_and_eval can be used to parse and
2937 evaluate an expression.
2939 * New remote packets
2942 Define a trace state variable.
2945 Get the current value of a trace state variable.
2948 Set desired tracing behavior upon disconnection.
2951 Set the trace buffer to be linear or circular.
2954 Get data about the tracepoints currently in use.
2958 Process record now works correctly with hardware watchpoints.
2960 Multiple bug fixes have been made to the mips-irix port, making it
2961 much more reliable. In particular:
2962 - Debugging threaded applications is now possible again. Previously,
2963 GDB would hang while starting the program, or while waiting for
2964 the program to stop at a breakpoint.
2965 - Attaching to a running process no longer hangs.
2966 - An error occurring while loading a core file has been fixed.
2967 - Changing the value of the PC register now works again. This fixes
2968 problems observed when using the "jump" command, or when calling
2969 a function from GDB, or even when assigning a new value to $pc.
2970 - With the "finish" and "return" commands, the return value for functions
2971 returning a small array is now correctly printed.
2972 - It is now possible to break on shared library code which gets executed
2973 during a shared library init phase (code executed while executing
2974 their .init section). Previously, the breakpoint would have no effect.
2975 - GDB is now able to backtrace through the signal handler for
2976 non-threaded programs.
2978 PIE (Position Independent Executable) programs debugging is now supported.
2979 This includes debugging execution of PIC (Position Independent Code) shared
2980 libraries although for that, it should be possible to run such libraries as an
2983 *** Changes in GDB 7.0
2985 * GDB now has an interface for JIT compilation. Applications that
2986 dynamically generate code can create symbol files in memory and register
2987 them with GDB. For users, the feature should work transparently, and
2988 for JIT developers, the interface is documented in the GDB manual in the
2989 "JIT Compilation Interface" chapter.
2991 * Tracepoints may now be conditional. The syntax is as for
2992 breakpoints; either an "if" clause appended to the "trace" command,
2993 or the "condition" command is available. GDB sends the condition to
2994 the target for evaluation using the same bytecode format as is used
2995 for tracepoint actions.
2997 * The disassemble command now supports: an optional /r modifier, print the
2998 raw instructions in hex as well as in symbolic form, and an optional /m
2999 modifier to print mixed source+assembly.
3001 * Process record and replay
3003 In a architecture environment that supports ``process record and
3004 replay'', ``process record and replay'' target can record a log of
3005 the process execution, and replay it with both forward and reverse
3008 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3009 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3010 set execution-direction {forward|reverse}, for targets that support
3013 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3014 feature is available with a native GDB running on kernel version
3017 * GDB now has support for multi-byte and wide character sets on the
3018 target. Strings whose character type is wchar_t, char16_t, or
3019 char32_t are now correctly printed. GDB supports wide- and unicode-
3020 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3021 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3022 `printf'. This feature requires iconv to work properly; if your
3023 system does not have a working iconv, GDB can use GNU libiconv. See
3024 the installation instructions for more information.
3026 * GDB now supports automatic retrieval of shared library files from
3027 remote targets. To use this feature, specify a system root that begins
3028 with the `remote:' prefix, either via the `set sysroot' command or via
3029 the `--with-sysroot' configure-time option.
3031 * "info sharedlibrary" now takes an optional regex of libraries to show,
3032 and it now reports if a shared library has no debugging information.
3034 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3035 now complete on file names.
3037 * When completing in expressions, gdb will attempt to limit
3038 completions to allowable structure or union fields, where appropriate.
3039 For instance, consider:
3041 # struct example { int f1; double f2; };
3042 # struct example variable;
3045 If the user types TAB at the end of this command line, the available
3046 completions will be "f1" and "f2".
3048 * Inlined functions are now supported. They show up in backtraces, and
3049 the "step", "next", and "finish" commands handle them automatically.
3051 * GDB now supports the token-splicing (##) and stringification (#)
3052 operators when expanding macros. It also supports variable-arity
3055 * GDB now supports inspecting extra signal information, exported by
3056 the new $_siginfo convenience variable. The feature is currently
3057 implemented on linux ARM, i386 and amd64.
3059 * GDB can now display the VFP floating point registers and NEON vector
3060 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3061 can provide these registers (requires Linux 2.6.30 or later). Remote
3062 and simulator targets may also provide them.
3064 * New remote packets
3067 Search memory for a sequence of bytes.
3070 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3071 operation over reliable transport links. Use of this packet is
3072 controlled by the `set remote noack-packet' command.
3075 Kill the process with the specified process ID. Use this in preference
3076 to `k' when multiprocess protocol extensions are supported.
3079 Obtains additional operating system information
3083 Read or write additional signal information.
3085 * Removed remote protocol undocumented extension
3087 An undocumented extension to the remote protocol's `S' stop reply
3088 packet that permited the stub to pass a process id was removed.
3089 Remote servers should use the `T' stop reply packet instead.
3091 * GDB now supports multiple function calling conventions according to the
3092 DWARF-2 DW_AT_calling_convention function attribute.
3094 * The SH target utilizes the aforementioned change to distinguish between gcc
3095 and Renesas calling convention. It also adds the new CLI commands
3096 `set/show sh calling-convention'.
3098 * GDB can now read compressed debug sections, as produced by GNU gold
3099 with the --compress-debug-sections=zlib flag.
3101 * 64-bit core files are now supported on AIX.
3103 * Thread switching is now supported on Tru64.
3105 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3106 which will be allocated using malloc later in program execution.
3108 * The qXfer:libraries:read remote procotol packet now allows passing a
3109 list of section offsets.
3111 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3112 conditions handling signals delivered during attach or thread creation
3113 have also been fixed.
3115 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3116 From the user's standpoint, all unqualified instances of True and False
3117 are treated as the standard definitions, regardless of context.
3119 * GDB now parses C++ symbol and type names more flexibly. For
3122 template<typename T> class C { };
3125 GDB will now correctly handle all of:
3127 ptype C<char const *>
3128 ptype C<char const*>
3129 ptype C<const char *>
3130 ptype C<const char*>
3132 * New features in the GDB remote stub, gdbserver
3134 - The "--wrapper" command-line argument tells gdbserver to use a
3135 wrapper program to launch programs for debugging.
3137 - On PowerPC and S/390 targets, it is now possible to use a single
3138 gdbserver executable to debug both 32-bit and 64-bit programs.
3139 (This requires gdbserver itself to be built as a 64-bit executable.)
3141 - gdbserver uses the new noack protocol mode for TCP connections to
3142 reduce communications latency, if also supported and enabled in GDB.
3144 - Support for the sparc64-linux-gnu target is now included in
3147 - The amd64-linux build of gdbserver now supports debugging both
3148 32-bit and 64-bit programs.
3150 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3151 now support hardware watchpoints, and will use them automatically
3156 GDB now has support for scripting using Python. Whether this is
3157 available is determined at configure time.
3159 New GDB commands can now be written in Python.
3161 * Ada tasking support
3163 Ada tasks can now be inspected in GDB. The following commands have
3167 Print the list of Ada tasks.
3169 Print detailed information about task number N.
3171 Print the task number of the current task.
3173 Switch the context of debugging to task number N.
3175 * Support for user-defined prefixed commands. The "define" command can
3176 add new commands to existing prefixes, e.g. "target".
3178 * Multi-inferior, multi-process debugging.
3180 GDB now has generalized support for multi-inferior debugging. See
3181 "Debugging Multiple Inferiors" in the manual for more information.
3182 Although availability still depends on target support, the command
3183 set is more uniform now. The GNU/Linux specific multi-forks support
3184 has been migrated to this new framework. This implied some user
3185 visible changes; see "New commands" and also "Removed commands"
3188 * Target descriptions can now describe the target OS ABI. See the
3189 "Target Description Format" section in the user manual for more
3192 * Target descriptions can now describe "compatible" architectures
3193 to indicate that the target can execute applications for a different
3194 architecture in addition to those for the main target architecture.
3195 See the "Target Description Format" section in the user manual for
3198 * Multi-architecture debugging.
3200 GDB now includes general supports for debugging applications on
3201 hybrid systems that use more than one single processor architecture
3202 at the same time. Each such hybrid architecture still requires
3203 specific support to be added. The only hybrid architecture supported
3204 in this version of GDB is the Cell Broadband Engine.
3206 * GDB now supports integrated debugging of Cell/B.E. applications that
3207 use both the PPU and SPU architectures. To enable support for hybrid
3208 Cell/B.E. debugging, you need to configure GDB to support both the
3209 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3210 --enable-targets configure option.
3212 * Non-stop mode debugging.
3214 For some targets, GDB now supports an optional mode of operation in
3215 which you can examine stopped threads while other threads continue
3216 to execute freely. This is referred to as non-stop mode, with the
3217 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3218 section in the user manual for more information.
3220 To be able to support remote non-stop debugging, a remote stub needs
3221 to implement the non-stop mode remote protocol extensions, as
3222 described in the "Remote Non-Stop" section of the user manual. The
3223 GDB remote stub, gdbserver, has been adjusted to support these
3224 extensions on linux targets.
3226 * New commands (for set/show, see "New options" below)
3228 catch syscall [NAME(S) | NUMBER(S)]
3229 Catch system calls. Arguments, which should be names of system
3230 calls or their numbers, mean catch only those syscalls. Without
3231 arguments, every syscall will be caught. When the inferior issues
3232 any of the specified syscalls, GDB will stop and announce the system
3233 call, both when it is called and when its call returns. This
3234 feature is currently available with a native GDB running on the
3235 Linux Kernel, under the following architectures: x86, x86_64,
3236 PowerPC and PowerPC64.
3238 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3240 Search memory for a sequence of bytes.
3242 maint set python print-stack
3243 maint show python print-stack
3244 Show a stack trace when an error is encountered in a Python script.
3247 Invoke CODE by passing it to the Python interpreter.
3252 These allow macros to be defined, undefined, and listed
3256 Show operating system information about processes.
3259 List the inferiors currently under GDB's control.
3262 Switch focus to inferior number NUM.
3265 Detach from inferior number NUM.
3268 Kill inferior number NUM.
3272 set spu stop-on-load
3273 show spu stop-on-load
3274 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3276 set spu auto-flush-cache
3277 show spu auto-flush-cache
3278 Control whether to automatically flush the software-managed cache
3279 during Cell/B.E. debugging.
3281 set sh calling-convention
3282 show sh calling-convention
3283 Control the calling convention used when calling SH target functions.
3286 show debug timestamp
3287 Control display of timestamps with GDB debugging output.
3289 set disassemble-next-line
3290 show disassemble-next-line
3291 Control display of disassembled source lines or instructions when
3294 set remote noack-packet
3295 show remote noack-packet
3296 Set/show the use of remote protocol QStartNoAckMode packet. See above
3297 under "New remote packets."
3299 set remote query-attached-packet
3300 show remote query-attached-packet
3301 Control use of remote protocol `qAttached' (query-attached) packet.
3303 set remote read-siginfo-object
3304 show remote read-siginfo-object
3305 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3308 set remote write-siginfo-object
3309 show remote write-siginfo-object
3310 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3313 set remote reverse-continue
3314 show remote reverse-continue
3315 Control use of remote protocol 'bc' (reverse-continue) packet.
3317 set remote reverse-step
3318 show remote reverse-step
3319 Control use of remote protocol 'bs' (reverse-step) packet.
3321 set displaced-stepping
3322 show displaced-stepping
3323 Control displaced stepping mode. Displaced stepping is a way to
3324 single-step over breakpoints without removing them from the debuggee.
3325 Also known as "out-of-line single-stepping".
3328 show debug displaced
3329 Control display of debugging info for displaced stepping.
3331 maint set internal-error
3332 maint show internal-error
3333 Control what GDB does when an internal error is detected.
3335 maint set internal-warning
3336 maint show internal-warning
3337 Control what GDB does when an internal warning is detected.
3342 Use a wrapper program to launch programs for debugging.
3344 set multiple-symbols (all|ask|cancel)
3345 show multiple-symbols
3346 The value of this variable can be changed to adjust the debugger behavior
3347 when an expression or a breakpoint location contains an ambiguous symbol
3348 name (an overloaded function name, for instance).
3350 set breakpoint always-inserted
3351 show breakpoint always-inserted
3352 Keep breakpoints always inserted in the target, as opposed to inserting
3353 them when resuming the target, and removing them when the target stops.
3354 This option can improve debugger performance on slow remote targets.
3356 set arm fallback-mode (arm|thumb|auto)
3357 show arm fallback-mode
3358 set arm force-mode (arm|thumb|auto)
3360 These commands control how ARM GDB determines whether instructions
3361 are ARM or Thumb. The default for both settings is auto, which uses
3362 the current CPSR value for instructions without symbols; previous
3363 versions of GDB behaved as if "set arm fallback-mode arm".
3365 set disable-randomization
3366 show disable-randomization
3367 Standalone programs run with the virtual address space randomization enabled
3368 by default on some platforms. This option keeps the addresses stable across
3369 multiple debugging sessions.
3373 Control whether other threads are stopped or not when some thread hits
3378 Requests that asynchronous execution is enabled in the target, if available.
3379 In this case, it's possible to resume target in the background, and interact
3380 with GDB while the target is running. "show target-async" displays the
3381 current state of asynchronous execution of the target.
3383 set target-wide-charset
3384 show target-wide-charset
3385 The target-wide-charset is the name of the character set that GDB
3386 uses when printing characters whose type is wchar_t.
3388 set tcp auto-retry (on|off)
3390 set tcp connect-timeout
3391 show tcp connect-timeout
3392 These commands allow GDB to retry failed TCP connections to a remote stub
3393 with a specified timeout period; this is useful if the stub is launched
3394 in parallel with GDB but may not be ready to accept connections immediately.
3396 set libthread-db-search-path
3397 show libthread-db-search-path
3398 Control list of directories which GDB will search for appropriate
3401 set schedule-multiple (on|off)
3402 show schedule-multiple
3403 Allow GDB to resume all threads of all processes or only threads of
3404 the current process.
3408 Use more aggressive caching for accesses to the stack. This improves
3409 performance of remote debugging (particularly backtraces) without
3410 affecting correctness.
3412 set interactive-mode (on|off|auto)
3413 show interactive-mode
3414 Control whether GDB runs in interactive mode (on) or not (off).
3415 When in interactive mode, GDB waits for the user to answer all
3416 queries. Otherwise, GDB does not wait and assumes the default
3417 answer. When set to auto (the default), GDB determines which
3418 mode to use based on the stdin settings.
3423 For program forks, this is replaced by the new more generic `info
3424 inferiors' command. To list checkpoints, you can still use the
3425 `info checkpoints' command, which was an alias for the `info forks'
3429 Replaced by the new `inferior' command. To switch between
3430 checkpoints, you can still use the `restart' command, which was an
3431 alias for the `fork' command.
3434 This is removed, since some targets don't have a notion of
3435 processes. To switch between processes, you can still use the
3436 `inferior' command using GDB's own inferior number.
3439 For program forks, this is replaced by the new more generic `kill
3440 inferior' command. To delete a checkpoint, you can still use the
3441 `delete checkpoint' command, which was an alias for the `delete
3445 For program forks, this is replaced by the new more generic `detach
3446 inferior' command. To detach a checkpoint, you can still use the
3447 `detach checkpoint' command, which was an alias for the `detach
3450 * New native configurations
3452 x86/x86_64 Darwin i[34567]86-*-darwin*
3454 x86_64 MinGW x86_64-*-mingw*
3458 Lattice Mico32 lm32-*
3459 x86 DICOS i[34567]86-*-dicos*
3460 x86_64 DICOS x86_64-*-dicos*
3463 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3464 (mingw32ce) debugging.
3470 These commands were actually not implemented on any target.
3472 *** Changes in GDB 6.8
3474 * New native configurations
3476 NetBSD/hppa hppa*-*netbsd*
3477 Xtensa GNU/Linux xtensa*-*-linux*
3481 NetBSD/hppa hppa*-*-netbsd*
3482 Xtensa GNU/Lunux xtensa*-*-linux*
3484 * Change in command line behavior -- corefiles vs. process ids.
3486 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3487 attaching to process NUMBER fails, GDB no longer attempts to open a
3488 core file named NUMBER. Attaching to a program using the -c option
3489 is no longer supported. Instead, use the '-p' or '--pid' options.
3491 * GDB can now be built as a native debugger for debugging Windows x86
3492 (mingw32) Portable Executable (PE) programs.
3494 * Pending breakpoints no longer change their number when their address
3497 * GDB now supports breakpoints with multiple locations,
3498 including breakpoints on C++ constructors, inside C++ templates,
3499 and in inlined functions.
3501 * GDB's ability to debug optimized code has been improved. GDB more
3502 accurately identifies function bodies and lexical blocks that occupy
3503 more than one contiguous range of addresses.
3505 * Target descriptions can now describe registers for PowerPC.
3507 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3508 registers on PowerPC targets.
3510 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3511 targets even when the libthread_db library is not available.
3513 * The GDB remote stub, gdbserver, now supports the new file transfer
3514 commands (remote put, remote get, and remote delete).
3516 * The GDB remote stub, gdbserver, now supports run and attach in
3517 extended-remote mode.
3519 * hppa*64*-*-hpux11* target broken
3520 The debugger is unable to start a program and fails with the following
3521 error: "Error trying to get information about dynamic linker".
3522 The gdb-6.7 release is also affected.
3524 * GDB now supports the --enable-targets= configure option to allow
3525 building a single GDB executable that supports multiple remote
3526 target architectures.
3528 * GDB now supports debugging C and C++ programs which use the
3529 Decimal Floating Point extension. In addition, the PowerPC target
3530 now has a set of pseudo-registers to inspect decimal float values
3531 stored in two consecutive float registers.
3533 * The -break-insert MI command can optionally create pending
3536 * Improved support for debugging Ada
3537 Many improvements to the Ada language support have been made. These
3539 - Better support for Ada2005 interface types
3540 - Improved handling of arrays and slices in general
3541 - Better support for Taft-amendment types
3542 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3544 - Improved command completion in Ada
3547 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3552 set print frame-arguments (all|scalars|none)
3553 show print frame-arguments
3554 The value of this variable can be changed to control which argument
3555 values should be printed by the debugger when displaying a frame.
3560 Transfer files to and from a remote target, and delete remote files.
3567 Transfer files to and from a remote target, and delete remote files.
3569 * New remote packets
3576 Open, close, read, write, and delete files on the remote system.
3579 Attach to an existing process on the remote system, in extended-remote
3583 Run a new process on the remote system, in extended-remote mode.
3585 *** Changes in GDB 6.7
3587 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3588 bfd, libiberty and opcodes, as revealed by static analysis donated by
3589 Coverity, Inc. (http://scan.coverity.com).
3591 * When looking up multiply-defined global symbols, GDB will now prefer the
3592 symbol definition in the current shared library if it was built using the
3593 -Bsymbolic linker option.
3595 * When the Text User Interface (TUI) is not configured, GDB will now
3596 recognize the -tui command-line option and print a message that the TUI
3599 * The GDB remote stub, gdbserver, now has lower overhead for high
3600 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3602 * GDB for MIPS targets now autodetects whether a remote target provides
3603 32-bit or 64-bit register values.
3605 * Support for C++ member pointers has been improved.
3607 * GDB now understands XML target descriptions, which specify the
3608 target's overall architecture. GDB can read a description from
3609 a local file or over the remote serial protocol.
3611 * Vectors of single-byte data use a new integer type which is not
3612 automatically displayed as character or string data.
3614 * The /s format now works with the print command. It displays
3615 arrays of single-byte integers and pointers to single-byte integers
3618 * Target descriptions can now describe target-specific registers,
3619 for architectures which have implemented the support (currently
3620 only ARM, M68K, and MIPS).
3622 * GDB and the GDB remote stub, gdbserver, now support the XScale
3625 * The GDB remote stub, gdbserver, has been updated to support
3626 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3627 has been rewritten to use the standard GDB remote protocol.
3629 * GDB can now step into C++ functions which are called through thunks.
3631 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3633 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3634 layout. It also supports a TextSeg= and DataSeg= response when only
3635 segment base addresses (rather than offsets) are available.
3637 * The /i format now outputs any trailing branch delay slot instructions
3638 immediately following the last instruction within the count specified.
3640 * The GDB remote protocol "T" stop reply packet now supports a
3641 "library" response. Combined with the new "qXfer:libraries:read"
3642 packet, this response allows GDB to debug shared libraries on targets
3643 where the operating system manages the list of loaded libraries (e.g.
3644 Windows and SymbianOS).
3646 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3647 (DLLs) on Windows and Windows CE targets.
3649 * GDB now supports a faster verification that a .debug file matches its binary
3650 according to its build-id signature, if the signature is present.
3656 Enable or disable hardware flow control (RTS/CTS) on the serial port
3657 when debugging using remote targets.
3659 set mem inaccessible-by-default
3660 show mem inaccessible-by-default
3661 If the target supplies a memory map, for instance via the remote
3662 protocol's "qXfer:memory-map:read" packet, setting this variable
3663 prevents GDB from accessing memory outside the memory map. This
3664 is useful for targets with memory mapped registers or which react
3665 badly to accesses of unmapped address space.
3667 set breakpoint auto-hw
3668 show breakpoint auto-hw
3669 If the target supplies a memory map, for instance via the remote
3670 protocol's "qXfer:memory-map:read" packet, setting this variable
3671 lets GDB use hardware breakpoints automatically for memory regions
3672 where it can not use software breakpoints. This covers both the
3673 "break" command and internal breakpoints used for other commands
3674 including "next" and "finish".
3677 catch exception unhandled
3678 Stop the program execution when Ada exceptions are raised.
3681 Stop the program execution when an Ada assertion failed.
3685 Set an alternate system root for target files. This is a more
3686 general version of "set solib-absolute-prefix", which is now
3687 an alias to "set sysroot".
3690 Provide extended SPU facility status information. This set of
3691 commands is available only when debugging the Cell/B.E. SPU
3694 * New native configurations
3696 OpenBSD/sh sh*-*openbsd*
3699 unset tdesc filename
3701 Use the specified local file as an XML target description, and do
3702 not query the target for its built-in description.
3706 OpenBSD/sh sh*-*-openbsd*
3707 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3708 Toshiba Media Processor mep-elf
3710 * New remote packets
3713 Ignore the specified signals; pass them directly to the debugged program
3714 without stopping other threads or reporting them to GDB.
3716 qXfer:features:read:
3717 Read an XML target description from the target, which describes its
3722 Read or write contents of an spufs file on the target system. These
3723 packets are available only on the Cell/B.E. SPU architecture.
3725 qXfer:libraries:read:
3726 Report the loaded shared libraries. Combined with new "T" packet
3727 response, this packet allows GDB to debug shared libraries on
3728 targets where the operating system manages the list of loaded
3729 libraries (e.g. Windows and SymbianOS).
3733 Support for these obsolete configurations has been removed.
3741 i[34567]86-*-lynxos*
3742 i[34567]86-*-netware*
3743 i[34567]86-*-sco3.2v5*
3744 i[34567]86-*-sco3.2v4*
3746 i[34567]86-*-sysv4.2*
3749 i[34567]86-*-unixware2*
3750 i[34567]86-*-unixware*
3759 * Other removed features
3766 Various m68k-only ROM monitors.
3773 Various Renesas ROM monitors and debugging interfaces for SH and
3778 Support for a Macraigor serial interface to on-chip debugging.
3779 GDB does not directly support the newer parallel or USB
3784 A debug information format. The predecessor to DWARF 2 and
3785 DWARF 3, which are still supported.
3787 Support for the HP aCC compiler on HP-UX/PA-RISC
3789 SOM-encapsulated symbolic debugging information, automatic
3790 invocation of pxdb, and the aCC custom C++ ABI. This does not
3791 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3792 with aCC can still be debugged on an assembly level.
3794 MIPS ".pdr" sections
3796 A MIPS-specific format used to describe stack frame layout
3797 in debugging information.
3801 GDB could work with an older version of Guile to debug
3802 the interpreter and Scheme programs running in it.
3804 set mips stack-arg-size
3805 set mips saved-gpreg-size
3807 Use "set mips abi" to control parameter passing for MIPS.
3809 *** Changes in GDB 6.6
3814 Cell Broadband Engine SPU spu-elf
3816 * GDB can now be configured as a cross-debugger targeting native Windows
3817 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3818 running on a Windows system over TCP/IP to debug Windows programs.
3820 * The GDB remote stub, gdbserver, has been updated to support Windows and
3821 Cygwin debugging. Both single-threaded and multi-threaded programs are
3824 * The "set trust-readonly-sections" command works again. This command was
3825 broken in GDB 6.3, 6.4, and 6.5.
3827 * The "load" command now supports writing to flash memory, if the remote
3828 stub provides the required support.
3830 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3831 longer requires symbolic debug information (e.g. DWARF-2).
3836 unset substitute-path
3837 show substitute-path
3838 Manage a list of substitution rules that GDB uses to rewrite the name
3839 of the directories where the sources are located. This can be useful
3840 for instance when the sources were moved to a different location
3841 between compilation and debugging.
3845 Print each CLI command as it is executed. Each command is prefixed with
3846 a number of `+' symbols representing the nesting depth.
3847 The source command now has a `-v' option to enable the same feature.
3851 The ARM Demon monitor support (RDP protocol, "target rdp").
3853 Kernel Object Display, an embedded debugging feature which only worked with
3854 an obsolete version of Cisco IOS.
3856 The 'set download-write-size' and 'show download-write-size' commands.
3858 * New remote packets
3861 Tell a stub about GDB client features, and request remote target features.
3862 The first feature implemented is PacketSize, which allows the target to
3863 specify the size of packets it can handle - to minimize the number of
3864 packets required and improve performance when connected to a remote
3868 Fetch an OS auxilliary vector from the remote stub. This packet is a
3869 more efficient replacement for qPart:auxv:read.
3871 qXfer:memory-map:read:
3872 Fetch a memory map from the remote stub, including information about
3873 RAM, ROM, and flash memory devices.
3878 Erase and program a flash memory device.
3880 * Removed remote packets
3883 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3884 used it, and only gdbserver implemented it.
3886 *** Changes in GDB 6.5
3890 Renesas M32C/M16C m32c-elf
3892 Morpho Technologies ms1 ms1-elf
3896 init-if-undefined Initialize a convenience variable, but
3897 only if it doesn't already have a value.
3899 The following commands are presently only implemented for native GNU/Linux:
3901 checkpoint Save a snapshot of the program state.
3903 restart <n> Return the program state to a
3904 previously saved state.
3906 info checkpoints List currently saved checkpoints.
3908 delete-checkpoint <n> Delete a previously saved checkpoint.
3910 set|show detach-on-fork Tell gdb whether to detach from a newly
3911 forked process, or to keep debugging it.
3913 info forks List forks of the user program that
3914 are available to be debugged.
3916 fork <n> Switch to debugging one of several
3917 forks of the user program that are
3918 available to be debugged.
3920 delete-fork <n> Delete a fork from the list of forks
3921 that are available to be debugged (and
3922 kill the forked process).
3924 detach-fork <n> Delete a fork from the list of forks
3925 that are available to be debugged (and
3926 allow the process to continue).
3930 Morpho Technologies ms2 ms1-elf
3932 * Improved Windows host support
3934 GDB now builds as a cross debugger hosted on i686-mingw32, including
3935 native console support, and remote communications using either
3936 network sockets or serial ports.
3938 * Improved Modula-2 language support
3940 GDB can now print most types in the Modula-2 syntax. This includes:
3941 basic types, set types, record types, enumerated types, range types,
3942 pointer types and ARRAY types. Procedure var parameters are correctly
3943 printed and hexadecimal addresses and character constants are also
3944 written in the Modula-2 syntax. Best results can be obtained by using
3945 GNU Modula-2 together with the -gdwarf-2 command line option.
3949 The ARM rdi-share module.
3951 The Netware NLM debug server.
3953 *** Changes in GDB 6.4
3955 * New native configurations
3957 OpenBSD/arm arm*-*-openbsd*
3958 OpenBSD/mips64 mips64-*-openbsd*
3962 Morpho Technologies ms1 ms1-elf
3964 * New command line options
3966 --batch-silent As for --batch, but totally silent.
3967 --return-child-result The debugger will exist with the same value
3968 the child (debugged) program exited with.
3969 --eval-command COMMAND, -ex COMMAND
3970 Execute a single GDB CLI command. This may be
3971 specified multiple times and in conjunction
3972 with the --command (-x) option.
3974 * Deprecated commands removed
3976 The following commands, that were deprecated in 2000, have been
3980 set|show arm disassembly-flavor set|show arm disassembler
3981 othernames set arm disassembler
3982 set|show remotedebug set|show debug remote
3983 set|show archdebug set|show debug arch
3984 set|show eventdebug set|show debug event
3987 * New BSD user-level threads support
3989 It is now possible to debug programs using the user-level threads
3990 library on OpenBSD and FreeBSD. Currently supported (target)
3993 FreeBSD/amd64 x86_64-*-freebsd*
3994 FreeBSD/i386 i386-*-freebsd*
3995 OpenBSD/i386 i386-*-openbsd*
3997 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3998 are not yet supported.
4000 * New support for Matsushita MN10300 w/sim added
4001 (Work in progress). mn10300-elf.
4003 * REMOVED configurations and files
4005 VxWorks and the XDR protocol *-*-vxworks
4006 Motorola MCORE mcore-*-*
4007 National Semiconductor NS32000 ns32k-*-*
4009 * New "set print array-indexes" command
4011 After turning this setting "on", GDB prints the index of each element
4012 when displaying arrays. The default is "off" to preserve the previous
4015 * VAX floating point support
4017 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4019 * User-defined command support
4021 In addition to using $arg0..$arg9 for argument passing, it is now possible
4022 to use $argc to determine now many arguments have been passed. See the
4023 section on user-defined commands in the user manual for more information.
4025 *** Changes in GDB 6.3:
4027 * New command line option
4029 GDB now accepts -l followed by a number to set the timeout for remote
4032 * GDB works with GCC -feliminate-dwarf2-dups
4034 GDB now supports a more compact representation of DWARF-2 debug
4035 information using DW_FORM_ref_addr references. These are produced
4036 by GCC with the option -feliminate-dwarf2-dups and also by some
4037 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4038 to use -feliminate-dwarf2-dups.
4040 * Internationalization
4042 When supported by the host system, GDB will be built with
4043 internationalization (libintl). The task of marking up the sources is
4044 continued, we're looking forward to our first translation.
4048 Initial support for debugging programs compiled with the GNAT
4049 implementation of the Ada programming language has been integrated
4050 into GDB. In this release, support is limited to expression evaluation.
4052 * New native configurations
4054 GNU/Linux/m32r m32r-*-linux-gnu
4058 GDB's remote protocol now includes support for the 'p' packet. This
4059 packet is used to fetch individual registers from a remote inferior.
4061 * END-OF-LIFE registers[] compatibility module
4063 GDB's internal register infrastructure has been completely rewritten.
4064 The new infrastructure making possible the implementation of key new
4065 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4068 GDB 6.3 will be the last release to include the the registers[]
4069 compatibility module that allowed out-of-date configurations to
4070 continue to work. This change directly impacts the following
4080 powerpc bdm protocol
4082 Unless there is activity to revive these configurations, they will be
4083 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4085 * OBSOLETE configurations and files
4087 Configurations that have been declared obsolete in this release have
4088 been commented out. Unless there is activity to revive these
4089 configurations, the next release of GDB will have their sources
4090 permanently REMOVED.
4099 *** Changes in GDB 6.2.1:
4101 * MIPS `break main; run' gave an heuristic-fence-post warning
4103 When attempting to run even a simple program, a warning about
4104 heuristic-fence-post being hit would be reported. This problem has
4107 * MIPS IRIX 'long double' crashed GDB
4109 When examining a long double variable, GDB would get a segmentation
4110 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4111 IRIX long double values).
4115 A bug in the VAX stack code was causing problems with the "next"
4116 command. This problem has been fixed.
4118 *** Changes in GDB 6.2:
4120 * Fix for ``many threads''
4122 On GNU/Linux systems that use the NPTL threads library, a program
4123 rapidly creating and deleting threads would confuse GDB leading to the
4126 ptrace: No such process.
4127 thread_db_get_info: cannot get thread info: generic error
4129 This problem has been fixed.
4131 * "-async" and "-noasync" options removed.
4133 Support for the broken "-noasync" option has been removed (it caused
4136 * New ``start'' command.
4138 This command runs the program until the begining of the main procedure.
4140 * New BSD Kernel Data Access Library (libkvm) interface
4142 Using ``target kvm'' it is now possible to debug kernel core dumps and
4143 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4144 platforms. Currently supported (native-only) configurations are:
4146 FreeBSD/amd64 x86_64-*-freebsd*
4147 FreeBSD/i386 i?86-*-freebsd*
4148 NetBSD/i386 i?86-*-netbsd*
4149 NetBSD/m68k m68*-*-netbsd*
4150 NetBSD/sparc sparc-*-netbsd*
4151 OpenBSD/amd64 x86_64-*-openbsd*
4152 OpenBSD/i386 i?86-*-openbsd*
4153 OpenBSD/m68k m68*-openbsd*
4154 OpenBSD/sparc sparc-*-openbsd*
4156 * Signal trampoline code overhauled
4158 Many generic problems with GDB's signal handling code have been fixed.
4159 These include: backtraces through non-contiguous stacks; recognition
4160 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4161 call; backtrace through a signal trampoline; step into and out of
4162 signal handlers; and single-stepping in the signal trampoline.
4164 Please note that kernel bugs are a limiting factor here. These
4165 features have been shown to work on an s390 GNU/Linux system that
4166 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4168 * Cygwin support for DWARF 2 added.
4170 * New native configurations
4172 GNU/Linux/hppa hppa*-*-linux*
4173 OpenBSD/hppa hppa*-*-openbsd*
4174 OpenBSD/m68k m68*-*-openbsd*
4175 OpenBSD/m88k m88*-*-openbsd*
4176 OpenBSD/powerpc powerpc-*-openbsd*
4177 NetBSD/vax vax-*-netbsd*
4178 OpenBSD/vax vax-*-openbsd*
4180 * END-OF-LIFE frame compatibility module
4182 GDB's internal frame infrastructure has been completely rewritten.
4183 The new infrastructure making it possible to support key new features
4184 including DWARF 2 Call Frame Information. To aid in the task of
4185 migrating old configurations to this new infrastructure, a
4186 compatibility module, that allowed old configurations to continue to
4187 work, was also included.
4189 GDB 6.2 will be the last release to include this frame compatibility
4190 module. This change directly impacts the following configurations:
4200 Unless there is activity to revive these configurations, they will be
4201 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4203 * REMOVED configurations and files
4205 Sun 3, running SunOS 3 m68*-*-sunos3*
4206 Sun 3, running SunOS 4 m68*-*-sunos4*
4207 Sun 2, running SunOS 3 m68000-*-sunos3*
4208 Sun 2, running SunOS 4 m68000-*-sunos4*
4209 Motorola 680x0 running LynxOS m68*-*-lynxos*
4210 AT&T 3b1/Unix pc m68*-att-*
4211 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4212 decstation mips-dec-* mips-little-*
4213 riscos mips-*-riscos* mips-*-sysv*
4214 sonymips mips-sony-*
4215 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4217 *** Changes in GDB 6.1.1:
4219 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4221 The TUI (Text-mode User Interface) is now built as part of a default
4222 GDB configuration. It is enabled by either selecting the TUI with the
4223 command line option "-i=tui" or by running the separate "gdbtui"
4224 program. For more information on the TUI, see the manual "Debugging
4227 * Pending breakpoint support (also included in GDB 6.1)
4229 Support has been added to allow you to specify breakpoints in shared
4230 libraries that have not yet been loaded. If a breakpoint location
4231 cannot be found, and the "breakpoint pending" option is set to auto,
4232 GDB queries you if you wish to make the breakpoint pending on a future
4233 shared-library load. If and when GDB resolves the breakpoint symbol,
4234 the pending breakpoint is removed as one or more regular breakpoints
4237 Pending breakpoints are very useful for GCJ Java debugging.
4239 * Fixed ISO-C build problems
4241 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4242 non ISO-C code that stopped them being built using a more strict ISO-C
4243 compiler (e.g., IBM's C compiler).
4245 * Fixed build problem on IRIX 5
4247 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4248 wasn't able to compile compile on an IRIX 5 system.
4250 * Added execute permission to gdb/gdbserver/configure
4252 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4253 permission. This bug would cause configure to fail on a number of
4254 systems (Solaris, IRIX). Ref: server/519.
4256 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4258 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4259 has been updated to use constant array sizes.
4261 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4263 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4264 its generated DWARF Call Frame Info. This encoding was causing GDB to
4265 panic, that panic has been fixed. Ref: gdb/1628.
4267 * Fixed a problem when examining parameters in shared library code.
4269 When examining parameters in optimized shared library code generated
4270 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4271 not available''. GDB now correctly displays the variable's value.
4273 *** Changes in GDB 6.1:
4275 * Removed --with-mmalloc
4277 Support for the mmalloc memory manager has been removed, as it
4278 conflicted with the internal gdb byte cache.
4280 * Changes in AMD64 configurations
4282 The AMD64 target now includes the %cs and %ss registers. As a result
4283 the AMD64 remote protocol has changed; this affects the floating-point
4284 and SSE registers. If you rely on those registers for your debugging,
4285 you should upgrade gdbserver on the remote side.
4287 * Revised SPARC target
4289 The SPARC target has been completely revised, incorporating the
4290 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4291 support for LynxOS and SunOS 4 has been dropped. Calling functions
4292 from within GDB on operating systems with a non-executable stack
4293 (Solaris, OpenBSD) now works.
4297 GDB has a new C++ demangler which does a better job on the mangled
4298 names generated by current versions of g++. It also runs faster, so
4299 with this and other changes gdb should now start faster on large C++
4302 * DWARF 2 Location Expressions
4304 GDB support for location expressions has been extended to support function
4305 arguments and frame bases. Older versions of GDB could crash when they
4308 * C++ nested types and namespaces
4310 GDB's support for nested types and namespaces in C++ has been
4311 improved, especially if you use the DWARF 2 debugging format. (This
4312 is the default for recent versions of GCC on most platforms.)
4313 Specifically, if you have a class "Inner" defined within a class or
4314 namespace "Outer", then GDB realizes that the class's name is
4315 "Outer::Inner", not simply "Inner". This should greatly reduce the
4316 frequency of complaints about not finding RTTI symbols. In addition,
4317 if you are stopped at inside of a function defined within a namespace,
4318 GDB modifies its name lookup accordingly.
4320 * New native configurations
4322 NetBSD/amd64 x86_64-*-netbsd*
4323 OpenBSD/amd64 x86_64-*-openbsd*
4324 OpenBSD/alpha alpha*-*-openbsd*
4325 OpenBSD/sparc sparc-*-openbsd*
4326 OpenBSD/sparc64 sparc64-*-openbsd*
4328 * New debugging protocols
4330 M32R with SDI protocol m32r-*-elf*
4332 * "set prompt-escape-char" command deleted.
4334 The command "set prompt-escape-char" has been deleted. This command,
4335 and its very obscure effet on GDB's prompt, was never documented,
4336 tested, nor mentioned in the NEWS file.
4338 * OBSOLETE configurations and files
4340 Configurations that have been declared obsolete in this release have
4341 been commented out. Unless there is activity to revive these
4342 configurations, the next release of GDB will have their sources
4343 permanently REMOVED.
4345 Sun 3, running SunOS 3 m68*-*-sunos3*
4346 Sun 3, running SunOS 4 m68*-*-sunos4*
4347 Sun 2, running SunOS 3 m68000-*-sunos3*
4348 Sun 2, running SunOS 4 m68000-*-sunos4*
4349 Motorola 680x0 running LynxOS m68*-*-lynxos*
4350 AT&T 3b1/Unix pc m68*-att-*
4351 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4352 decstation mips-dec-* mips-little-*
4353 riscos mips-*-riscos* mips-*-sysv*
4354 sonymips mips-sony-*
4355 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4357 * REMOVED configurations and files
4359 SGI Irix-4.x mips-sgi-irix4 or iris4
4360 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4361 Z8000 simulator z8k-zilog-none or z8ksim
4362 Matsushita MN10200 w/simulator mn10200-*-*
4363 H8/500 simulator h8500-hitachi-hms or h8500hms
4364 HP/PA running BSD hppa*-*-bsd*
4365 HP/PA running OSF/1 hppa*-*-osf*
4366 HP/PA Pro target hppa*-*-pro*
4367 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4368 386BSD i[3456]86-*-bsd*
4369 Sequent family i[3456]86-sequent-sysv4*
4370 i[3456]86-sequent-sysv*
4371 i[3456]86-sequent-bsd*
4372 SPARC running LynxOS sparc-*-lynxos*
4373 SPARC running SunOS 4 sparc-*-sunos4*
4374 Tsqware Sparclet sparclet-*-*
4375 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4377 *** Changes in GDB 6.0:
4381 Support for debugging the Objective-C programming language has been
4382 integrated into GDB.
4384 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4386 DWARF 2's Call Frame Information makes available compiler generated
4387 information that more exactly describes the program's run-time stack.
4388 By using this information, GDB is able to provide more robust stack
4391 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4392 have been updated to use a new backtrace mechanism which includes
4393 DWARF 2 CFI support.
4397 GDB's remote protocol has been extended to include support for hosted
4398 file I/O (where the remote target uses GDB's file system). See GDB's
4399 remote protocol documentation for details.
4401 * All targets using the new architecture framework.
4403 All of GDB's targets have been updated to use the new internal
4404 architecture framework. The way is now open for future GDB releases
4405 to include cross-architecture native debugging support (i386 on amd64,
4408 * GNU/Linux's Thread Local Storage (TLS)
4410 GDB now includes support for for the GNU/Linux implementation of
4411 per-thread variables.
4413 * GNU/Linux's Native POSIX Thread Library (NPTL)
4415 GDB's thread code has been updated to work with either the new
4416 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4418 * Separate debug info.
4420 GDB, in conjunction with BINUTILS, now supports a mechanism for
4421 automatically loading debug information from a separate file. Instead
4422 of shipping full debug and non-debug versions of system libraries,
4423 system integrators can now instead ship just the stripped libraries
4424 and optional debug files.
4426 * DWARF 2 Location Expressions
4428 DWARF 2 Location Expressions allow the compiler to more completely
4429 describe the location of variables (even in optimized code) to the
4432 GDB now includes preliminary support for location expressions (support
4433 for DW_OP_piece is still missing).
4437 A number of long standing bugs that caused GDB to die while starting a
4438 Java application have been fixed. GDB's Java support is now
4439 considered "useable".
4441 * GNU/Linux support for fork, vfork, and exec.
4443 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4444 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4447 * GDB supports logging output to a file
4449 There are two new commands, "set logging" and "show logging", which can be
4450 used to capture GDB's output to a file.
4452 * The meaning of "detach" has changed for gdbserver
4454 The "detach" command will now resume the application, as documented. To
4455 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4458 * d10v, m68hc11 `regs' command deprecated
4460 The `info registers' command has been updated so that it displays the
4461 registers using a format identical to the old `regs' command.
4465 A new command, "maint set profile on/off", has been added. This command can
4466 be used to enable or disable profiling while running GDB, to profile a
4467 session or a set of commands. In addition there is a new configure switch,
4468 "--enable-profiling", which will cause GDB to be compiled with profiling
4469 data, for more informative profiling results.
4471 * Default MI syntax changed to "mi2".
4473 The default MI (machine interface) syntax, enabled by the command line
4474 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4475 "mi1", can be enabled by specifying the option "-i=mi1".
4477 Support for the original "mi0" syntax (included in GDB 5.0) has been
4480 Fix for gdb/192: removed extraneous space when displaying frame level.
4481 Fix for gdb/672: update changelist is now output in mi list format.
4482 Fix for gdb/702: a -var-assign that updates the value now shows up
4483 in a subsequent -var-update.
4485 * New native configurations.
4487 FreeBSD/amd64 x86_64-*-freebsd*
4489 * Multi-arched targets.
4491 HP/PA HPUX11 hppa*-*-hpux*
4492 Renesas M32R/D w/simulator m32r-*-elf*
4494 * OBSOLETE configurations and files
4496 Configurations that have been declared obsolete in this release have
4497 been commented out. Unless there is activity to revive these
4498 configurations, the next release of GDB will have their sources
4499 permanently REMOVED.
4501 Z8000 simulator z8k-zilog-none or z8ksim
4502 Matsushita MN10200 w/simulator mn10200-*-*
4503 H8/500 simulator h8500-hitachi-hms or h8500hms
4504 HP/PA running BSD hppa*-*-bsd*
4505 HP/PA running OSF/1 hppa*-*-osf*
4506 HP/PA Pro target hppa*-*-pro*
4507 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4508 Sequent family i[3456]86-sequent-sysv4*
4509 i[3456]86-sequent-sysv*
4510 i[3456]86-sequent-bsd*
4511 Tsqware Sparclet sparclet-*-*
4512 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4514 * REMOVED configurations and files
4517 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4518 IBM AIX PS/2 i[3456]86-*-aix
4519 i386 running Mach 3.0 i[3456]86-*-mach3*
4520 i386 running Mach i[3456]86-*-mach*
4521 i386 running OSF/1 i[3456]86-*osf1mk*
4522 HP/Apollo 68k Family m68*-apollo*-sysv*,
4524 m68*-hp-bsd*, m68*-hp-hpux*
4525 Argonaut Risc Chip (ARC) arc-*-*
4526 Mitsubishi D30V d30v-*-*
4527 Fujitsu FR30 fr30-*-elf*
4528 OS/9000 i[34]86-*-os9k
4529 I960 with MON960 i960-*-coff
4531 * MIPS $fp behavior changed
4533 The convenience variable $fp, for the MIPS, now consistently returns
4534 the address of the current frame's base. Previously, depending on the
4535 context, $fp could refer to either $sp or the current frame's base
4536 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4537 The GNU Source-Level Debugger''.
4539 *** Changes in GDB 5.3:
4541 * GNU/Linux shared library multi-threaded performance improved.
4543 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4544 `/proc', in preference to `ptrace' for memory reads. This may result
4545 in an improvement in the start-up time of multi-threaded, shared
4546 library applications when run under GDB. One GDB user writes: ``loads
4547 shared libs like mad''.
4549 * ``gdbserver'' now supports multi-threaded applications on some targets
4551 Support for debugging multi-threaded applications which use
4552 the GNU/Linux LinuxThreads package has been added for
4553 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4554 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4556 * GDB now supports C/C++ preprocessor macros.
4558 GDB now expands preprocessor macro invocations in C/C++ expressions,
4559 and provides various commands for showing macro definitions and how
4562 The new command `macro expand EXPRESSION' expands any macro
4563 invocations in expression, and shows the result.
4565 The new command `show macro MACRO-NAME' shows the definition of the
4566 macro named MACRO-NAME, and where it was defined.
4568 Most compilers don't include information about macros in the debugging
4569 information by default. In GCC 3.1, for example, you need to compile
4570 your program with the options `-gdwarf-2 -g3'. If the macro
4571 information is present in the executable, GDB will read it.
4573 * Multi-arched targets.
4575 DEC Alpha (partial) alpha*-*-*
4576 DEC VAX (partial) vax-*-*
4578 National Semiconductor NS32000 (partial) ns32k-*-*
4579 Motorola 68000 (partial) m68k-*-*
4580 Motorola MCORE mcore-*-*
4584 Fujitsu FRV architecture added by Red Hat frv*-*-*
4587 * New native configurations
4589 Alpha NetBSD alpha*-*-netbsd*
4590 SH NetBSD sh*-*-netbsdelf*
4591 MIPS NetBSD mips*-*-netbsd*
4592 UltraSPARC NetBSD sparc64-*-netbsd*
4594 * OBSOLETE configurations and files
4596 Configurations that have been declared obsolete in this release have
4597 been commented out. Unless there is activity to revive these
4598 configurations, the next release of GDB will have their sources
4599 permanently REMOVED.
4601 Mitsubishi D30V d30v-*-*
4602 OS/9000 i[34]86-*-os9k
4603 IBM AIX PS/2 i[3456]86-*-aix
4604 Fujitsu FR30 fr30-*-elf*
4605 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4606 Argonaut Risc Chip (ARC) arc-*-*
4607 i386 running Mach 3.0 i[3456]86-*-mach3*
4608 i386 running Mach i[3456]86-*-mach*
4609 i386 running OSF/1 i[3456]86-*osf1mk*
4610 HP/Apollo 68k Family m68*-apollo*-sysv*,
4612 m68*-hp-bsd*, m68*-hp-hpux*
4613 I960 with MON960 i960-*-coff
4615 * OBSOLETE languages
4617 CHILL, a Pascal like language used by telecommunications companies.
4619 * REMOVED configurations and files
4621 AMD 29k family via UDI a29k-amd-udi, udi29k
4622 A29K VxWorks a29k-*-vxworks
4623 AMD 29000 embedded, using EBMON a29k-none-none
4624 AMD 29000 embedded with COFF a29k-none-coff
4625 AMD 29000 embedded with a.out a29k-none-aout
4627 testsuite/gdb.hp/gdb.threads-hp/ directory
4629 * New command "set max-user-call-depth <nnn>"
4631 This command allows the user to limit the call depth of user-defined
4632 commands. The default is 1024.
4634 * Changes in FreeBSD/i386 native debugging.
4636 Support for the "generate-core-file" has been added.
4638 * New commands "dump", "append", and "restore".
4640 These commands allow data to be copied from target memory
4641 to a bfd-format or binary file (dump and append), and back
4642 from a file into memory (restore).
4644 * Improved "next/step" support on multi-processor Alpha Tru64.
4646 The previous single-step mechanism could cause unpredictable problems,
4647 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4648 of a software single-step mechanism prevents this.
4650 *** Changes in GDB 5.2.1:
4658 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4659 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4660 Fix, by Joel Brobecker imported from mainline.
4662 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4663 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4664 Fix, by Fred Fish, imported from mainline.
4666 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4667 Surprisingly enough, it works now.
4668 By Michal Ludvig, imported from mainline.
4670 i386 hardware watchpoint support:
4671 avoid misses on second run for some targets.
4672 By Pierre Muller, imported from mainline.
4674 *** Changes in GDB 5.2:
4676 * New command "set trust-readonly-sections on[off]".
4678 This command is a hint that tells gdb that read-only sections
4679 really are read-only (ie. that their contents will not change).
4680 In this mode, gdb will go to the object file rather than the
4681 target to read memory from read-only sections (such as ".text").
4682 This can be a significant performance improvement on some
4683 (notably embedded) targets.
4685 * New command "generate-core-file" (or "gcore").
4687 This new gdb command allows the user to drop a core file of the child
4688 process state at any time. So far it's been implemented only for
4689 GNU/Linux and Solaris, but should be relatively easily ported to other
4690 hosts. Argument is core file name (defaults to core.<pid>).
4692 * New command line option
4694 GDB now accepts --pid or -p followed by a process id.
4696 * Change in command line behavior -- corefiles vs. process ids.
4698 There is a subtle behavior in the way in which GDB handles
4699 command line arguments. The first non-flag argument is always
4700 a program to debug, but the second non-flag argument may either
4701 be a corefile or a process id. Previously, GDB would attempt to
4702 open the second argument as a corefile, and if that failed, would
4703 issue a superfluous error message and then attempt to attach it as
4704 a process. Now, if the second argument begins with a non-digit,
4705 it will be treated as a corefile. If it begins with a digit,
4706 GDB will attempt to attach it as a process, and if no such process
4707 is found, will then attempt to open it as a corefile.
4709 * Changes in ARM configurations.
4711 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4712 configuration is fully multi-arch.
4714 * New native configurations
4716 ARM NetBSD arm*-*-netbsd*
4717 x86 OpenBSD i[3456]86-*-openbsd*
4718 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4719 Sparc64 running FreeBSD sparc64-*-freebsd*
4723 Sanyo XStormy16 xstormy16-elf
4725 * OBSOLETE configurations and files
4727 Configurations that have been declared obsolete in this release have
4728 been commented out. Unless there is activity to revive these
4729 configurations, the next release of GDB will have their sources
4730 permanently REMOVED.
4732 AMD 29k family via UDI a29k-amd-udi, udi29k
4733 A29K VxWorks a29k-*-vxworks
4734 AMD 29000 embedded, using EBMON a29k-none-none
4735 AMD 29000 embedded with COFF a29k-none-coff
4736 AMD 29000 embedded with a.out a29k-none-aout
4738 testsuite/gdb.hp/gdb.threads-hp/ directory
4740 * REMOVED configurations and files
4742 TI TMS320C80 tic80-*-*
4744 PowerPC Solaris powerpcle-*-solaris*
4745 PowerPC Windows NT powerpcle-*-cygwin32
4746 PowerPC Netware powerpc-*-netware*
4747 Harris/CXUX m88k m88*-harris-cxux*
4748 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4749 ns32k-utek-sysv* ns32k-utek-*
4750 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4751 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4752 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4753 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4754 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4756 * Changes to command line processing
4758 The new `--args' feature can be used to specify command-line arguments
4759 for the inferior from gdb's command line.
4761 * Changes to key bindings
4763 There is a new `operate-and-get-next' function bound to `C-o'.
4765 *** Changes in GDB 5.1.1
4767 Fix compile problem on DJGPP.
4769 Fix a problem with floating-point registers on the i386 being
4772 Fix to stop GDB crashing on .debug_str debug info.
4774 Numerous documentation fixes.
4776 Numerous testsuite fixes.
4778 *** Changes in GDB 5.1:
4780 * New native configurations
4782 Alpha FreeBSD alpha*-*-freebsd*
4783 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4784 MIPS GNU/Linux mips*-*-linux*
4785 MIPS SGI Irix 6.x mips*-sgi-irix6*
4786 ia64 AIX ia64-*-aix*
4787 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4791 Motorola 68HC11 and 68HC12 m68hc11-elf
4793 UltraSparc running GNU/Linux sparc64-*-linux*
4795 * OBSOLETE configurations and files
4797 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4798 Harris/CXUX m88k m88*-harris-cxux*
4799 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4800 ns32k-utek-sysv* ns32k-utek-*
4801 TI TMS320C80 tic80-*-*
4803 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4804 PowerPC Solaris powerpcle-*-solaris*
4805 PowerPC Windows NT powerpcle-*-cygwin32
4806 PowerPC Netware powerpc-*-netware*
4807 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4808 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4809 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4810 Apple Macintosh (MPW) host N/A
4812 stuff.c (Program to stuff files into a specially prepared space in kdb)
4813 kdb-start.c (Main loop for the standalone kernel debugger)
4815 Configurations that have been declared obsolete in this release have
4816 been commented out. Unless there is activity to revive these
4817 configurations, the next release of GDB will have their sources
4818 permanently REMOVED.
4820 * REMOVED configurations and files
4822 Altos 3068 m68*-altos-*
4823 Convex c1-*-*, c2-*-*
4825 ARM RISCix arm-*-* (as host)
4829 * GDB has been converted to ISO C.
4831 GDB's source code has been converted to ISO C. In particular, the
4832 sources are fully protoized, and rely on standard headers being
4837 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4839 * The MI enabled by default.
4841 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4842 revised and enabled by default. Packages which use GDB as a debugging
4843 engine behind a UI or another front end are encouraged to switch to
4844 using the GDB/MI interface, instead of the old annotations interface
4845 which is now deprecated.
4847 * Support for debugging Pascal programs.
4849 GDB now includes support for debugging Pascal programs. The following
4850 main features are supported:
4852 - Pascal-specific data types such as sets;
4854 - automatic recognition of Pascal sources based on file-name
4857 - Pascal-style display of data types, variables, and functions;
4859 - a Pascal expression parser.
4861 However, some important features are not yet supported.
4863 - Pascal string operations are not supported at all;
4865 - there are some problems with boolean types;
4867 - Pascal type hexadecimal constants are not supported
4868 because they conflict with the internal variables format;
4870 - support for Pascal objects and classes is not full yet;
4872 - unlike Pascal, GDB is case-sensitive for symbol names.
4874 * Changes in completion.
4876 Commands such as `shell', `run' and `set args', which pass arguments
4877 to inferior programs, now complete on file names, similar to what
4878 users expect at the shell prompt.
4880 Commands which accept locations, such as `disassemble', `print',
4881 `breakpoint', `until', etc. now complete on filenames as well as
4882 program symbols. Thus, if you type "break foob TAB", and the source
4883 files linked into the programs include `foobar.c', that file name will
4884 be one of the candidates for completion. However, file names are not
4885 considered for completion after you typed a colon that delimits a file
4886 name from a name of a function in that file, as in "break foo.c:bar".
4888 `set demangle-style' completes on available demangling styles.
4890 * New platform-independent commands:
4892 It is now possible to define a post-hook for a command as well as a
4893 hook that runs before the command. For more details, see the
4894 documentation of `hookpost' in the GDB manual.
4896 * Changes in GNU/Linux native debugging.
4898 Support for debugging multi-threaded programs has been completely
4899 revised for all platforms except m68k and sparc. You can now debug as
4900 many threads as your system allows you to have.
4902 Attach/detach is supported for multi-threaded programs.
4904 Support for SSE registers was added for x86. This doesn't work for
4905 multi-threaded programs though.
4907 * Changes in MIPS configurations.
4909 Multi-arch support is enabled for all MIPS configurations.
4911 GDB can now be built as native debugger on SGI Irix 6.x systems for
4912 debugging n32 executables. (Debugging 64-bit executables is not yet
4915 * Unified support for hardware watchpoints in all x86 configurations.
4917 Most (if not all) native x86 configurations support hardware-assisted
4918 breakpoints and watchpoints in a unified manner. This support
4919 implements debug register sharing between watchpoints, which allows to
4920 put a virtually infinite number of watchpoints on the same address,
4921 and also supports watching regions up to 16 bytes with several debug
4924 The new maintenance command `maintenance show-debug-regs' toggles
4925 debugging print-outs in functions that insert, remove, and test
4926 watchpoints and hardware breakpoints.
4928 * Changes in the DJGPP native configuration.
4930 New command ``info dos sysinfo'' displays assorted information about
4931 the CPU, OS, memory, and DPMI server.
4933 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4934 display information about segment descriptors stored in GDT, LDT, and
4937 New commands ``info dos pde'' and ``info dos pte'' display entries
4938 from Page Directory and Page Tables (for now works with CWSDPMI only).
4939 New command ``info dos address-pte'' displays the Page Table entry for
4940 a given linear address.
4942 GDB can now pass command lines longer than 126 characters to the
4943 program being debugged (requires an update to the libdbg.a library
4944 which is part of the DJGPP development kit).
4946 DWARF2 debug info is now supported.
4948 It is now possible to `step' and `next' through calls to `longjmp'.
4950 * Changes in documentation.
4952 All GDB documentation was converted to GFDL, the GNU Free
4953 Documentation License.
4955 Tracepoints-related commands are now fully documented in the GDB
4958 TUI, the Text-mode User Interface, is now documented in the manual.
4960 Tracepoints-related commands are now fully documented in the GDB
4963 The "GDB Internals" manual now has an index. It also includes
4964 documentation of `ui_out' functions, GDB coding standards, x86
4965 hardware watchpoints, and memory region attributes.
4967 * GDB's version number moved to ``version.in''
4969 The Makefile variable VERSION has been replaced by the file
4970 ``version.in''. People creating GDB distributions should update the
4971 contents of this file.
4975 GUD support is now a standard part of the EMACS distribution.
4977 *** Changes in GDB 5.0:
4979 * Improved support for debugging FP programs on x86 targets
4981 Unified and much-improved support for debugging floating-point
4982 programs on all x86 targets. In particular, ``info float'' now
4983 displays the FP registers in the same format on all x86 targets, with
4984 greater level of detail.
4986 * Improvements and bugfixes in hardware-assisted watchpoints
4988 It is now possible to watch array elements, struct members, and
4989 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4990 on x86 targets no longer erroneously trigger when the address is
4993 * Improvements in the native DJGPP version of GDB
4995 The distribution now includes all the scripts and auxiliary files
4996 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4997 machines ``out of the box''.
4999 The DJGPP version can now debug programs that use signals. It is
5000 possible to catch signals that happened in the debuggee, deliver
5001 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5002 would kill the program being debugged.) Programs that hook hardware
5003 interrupts (keyboard, timer, etc.) can also be debugged.
5005 It is now possible to debug DJGPP programs that redirect their
5006 standard handles or switch them to raw (as opposed to cooked) mode, or
5007 even close them. The command ``run < foo > bar'' works as expected,
5008 and ``info terminal'' reports useful information about the debuggee's
5009 terminal, including raw/cooked mode, redirection, etc.
5011 The DJGPP version now uses termios functions for console I/O, which
5012 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5015 DOS-style file names with drive letters are now fully supported by
5018 It is now possible to debug DJGPP programs that switch their working
5019 directory. It is also possible to rerun the debuggee any number of
5020 times without restarting GDB; thus, you can use the same setup,
5021 breakpoints, etc. for many debugging sessions.
5023 * New native configurations
5025 ARM GNU/Linux arm*-*-linux*
5026 PowerPC GNU/Linux powerpc-*-linux*
5030 Motorola MCore mcore-*-*
5031 x86 VxWorks i[3456]86-*-vxworks*
5032 PowerPC VxWorks powerpc-*-vxworks*
5033 TI TMS320C80 tic80-*-*
5035 * OBSOLETE configurations
5037 Altos 3068 m68*-altos-*
5038 Convex c1-*-*, c2-*-*
5040 ARM RISCix arm-*-* (as host)
5043 Configurations that have been declared obsolete will be commented out,
5044 but the code will be left in place. If there is no activity to revive
5045 these configurations before the next release of GDB, the sources will
5046 be permanently REMOVED.
5048 * Gould support removed
5050 Support for the Gould PowerNode and NP1 has been removed.
5052 * New features for SVR4
5054 On SVR4 native platforms (such as Solaris), if you attach to a process
5055 without first loading a symbol file, GDB will now attempt to locate and
5056 load symbols from the running process's executable file.
5058 * Many C++ enhancements
5060 C++ support has been greatly improved. Overload resolution now works properly
5061 in almost all cases. RTTI support is on the way.
5063 * Remote targets can connect to a sub-program
5065 A popen(3) style serial-device has been added. This device starts a
5066 sub-process (such as a stand-alone simulator) and then communicates
5067 with that. The sub-program to run is specified using the syntax
5068 ``|<program> <args>'' vis:
5070 (gdb) set remotedebug 1
5071 (gdb) target extended-remote |mn10300-elf-sim program-args
5073 * MIPS 64 remote protocol
5075 A long standing bug in the mips64 remote protocol where by GDB
5076 expected certain 32 bit registers (ex SR) to be transfered as 32
5077 instead of 64 bits has been fixed.
5079 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5080 added to provide backward compatibility with older versions of GDB.
5082 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5084 The command ``set remotebinarydownload'' command has been replaced by
5085 ``set remote X-packet''. Other commands in ``set remote'' family
5086 include ``set remote P-packet''.
5088 * Breakpoint commands accept ranges.
5090 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5091 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5092 ``tracepoint passcount'' also accepts a range of tracepoints.
5094 * ``apropos'' command added.
5096 The ``apropos'' command searches through command names and
5097 documentation strings, printing out matches, making it much easier to
5098 try to find a command that does what you are looking for.
5102 A new machine oriented interface (MI) has been added to GDB. This
5103 interface is designed for debug environments running GDB as a separate
5104 process. This is part of the long term libGDB project. See the
5105 "GDB/MI" chapter of the GDB manual for further information. It can be
5106 enabled by configuring with:
5108 .../configure --enable-gdbmi
5110 *** Changes in GDB-4.18:
5112 * New native configurations
5114 HP-UX 10.20 hppa*-*-hpux10.20
5115 HP-UX 11.x hppa*-*-hpux11.0*
5116 M68K GNU/Linux m68*-*-linux*
5120 Fujitsu FR30 fr30-*-elf*
5121 Intel StrongARM strongarm-*-*
5122 Mitsubishi D30V d30v-*-*
5124 * OBSOLETE configurations
5126 Gould PowerNode, NP1 np1-*-*, pn-*-*
5128 Configurations that have been declared obsolete will be commented out,
5129 but the code will be left in place. If there is no activity to revive
5130 these configurations before the next release of GDB, the sources will
5131 be permanently REMOVED.
5135 As a compatibility experiment, GDB's source files buildsym.h and
5136 buildsym.c have been converted to pure standard C, no longer
5137 containing any K&R compatibility code. We believe that all systems in
5138 use today either come with a standard C compiler, or have a GCC port
5139 available. If this is not true, please report the affected
5140 configuration to bug-gdb@gnu.org immediately. See the README file for
5141 information about getting a standard C compiler if you don't have one
5146 GDB now uses readline 2.2.
5148 * set extension-language
5150 You can now control the mapping between filename extensions and source
5151 languages by using the `set extension-language' command. For instance,
5152 you can ask GDB to treat .c files as C++ by saying
5153 set extension-language .c c++
5154 The command `info extensions' lists all of the recognized extensions
5155 and their associated languages.
5157 * Setting processor type for PowerPC and RS/6000
5159 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5160 you can use the `set processor' command to specify what variant of the
5161 PowerPC family you are debugging. The command
5165 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5166 following PowerPC and RS6000 variants:
5168 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5169 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5171 403GC IBM PowerPC 403GC
5172 505 Motorola PowerPC 505
5173 860 Motorola PowerPC 860 or 850
5174 601 Motorola PowerPC 601
5175 602 Motorola PowerPC 602
5176 603 Motorola/IBM PowerPC 603 or 603e
5177 604 Motorola PowerPC 604 or 604e
5178 750 Motorola/IBM PowerPC 750 or 750
5180 At the moment, this command just tells GDB what to name the
5181 special-purpose processor registers. Since almost all the affected
5182 registers are inaccessible to user-level programs, this command is
5183 only useful for remote debugging in its present form.
5187 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5188 more extensive support for HP-UX. Added features include shared
5189 library support, kernel threads and hardware watchpoints for 11.00,
5190 support for HP's ANSI C and C++ compilers, and a compatibility mode
5191 for xdb and dbx commands.
5195 HP's donation includes the new concept of catchpoints, which is a
5196 generalization of the old catch command. On HP-UX, it is now possible
5197 to catch exec, fork, and vfork, as well as library loading.
5199 This means that the existing catch command has changed; its first
5200 argument now specifies the type of catch to be set up. See the
5201 output of "help catch" for a list of catchpoint types.
5203 * Debugging across forks
5205 On HP-UX, you can choose which process to debug when a fork() happens
5210 HP has donated a curses-based terminal user interface (TUI). To get
5211 it, build with --enable-tui. Although this can be enabled for any
5212 configuration, at present it only works for native HP debugging.
5214 * GDB remote protocol additions
5216 A new protocol packet 'X' that writes binary data is now available.
5217 Default behavior is to try 'X', then drop back to 'M' if the stub
5218 fails to respond. The settable variable `remotebinarydownload'
5219 allows explicit control over the use of 'X'.
5221 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5222 full 64-bit address. The command
5224 set remoteaddresssize 32
5226 can be used to revert to the old behaviour. For existing remote stubs
5227 the change should not be noticed, as the additional address information
5230 In order to assist in debugging stubs, you may use the maintenance
5231 command `packet' to send any text string to the stub. For instance,
5233 maint packet heythere
5235 sends the packet "$heythere#<checksum>". Note that it is very easy to
5236 disrupt a debugging session by sending the wrong packet at the wrong
5239 The compare-sections command allows you to compare section data on the
5240 target to what is in the executable file without uploading or
5241 downloading, by comparing CRC checksums.
5243 * Tracing can collect general expressions
5245 You may now collect general expressions at tracepoints. This requires
5246 further additions to the target-side stub; see tracepoint.c and
5247 doc/agentexpr.texi for further details.
5249 * mask-address variable for Mips
5251 For Mips targets, you may control the zeroing of the upper 32 bits of
5252 a 64-bit address by entering `set mask-address on'. This is mainly
5253 of interest to users of embedded R4xxx and R5xxx processors.
5255 * Higher serial baud rates
5257 GDB's serial code now allows you to specify baud rates 57600, 115200,
5258 230400, and 460800 baud. (Note that your host system may not be able
5259 to achieve all of these rates.)
5263 The i960 configuration now includes an initial implementation of a
5264 builtin simulator, contributed by Jim Wilson.
5267 *** Changes in GDB-4.17:
5269 * New native configurations
5271 Alpha GNU/Linux alpha*-*-linux*
5272 Unixware 2.x i[3456]86-unixware2*
5273 Irix 6.x mips*-sgi-irix6*
5274 PowerPC GNU/Linux powerpc-*-linux*
5275 PowerPC Solaris powerpcle-*-solaris*
5276 Sparc GNU/Linux sparc-*-linux*
5277 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5281 Argonaut Risc Chip (ARC) arc-*-*
5282 Hitachi H8/300S h8300*-*-*
5283 Matsushita MN10200 w/simulator mn10200-*-*
5284 Matsushita MN10300 w/simulator mn10300-*-*
5285 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5286 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5287 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5288 Mitsubishi D10V w/simulator d10v-*-*
5289 Mitsubishi M32R/D w/simulator m32r-*-elf*
5290 Tsqware Sparclet sparclet-*-*
5291 NEC V850 w/simulator v850-*-*
5293 * New debugging protocols
5295 ARM with RDI protocol arm*-*-*
5296 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5297 DDB and LSI variants of PMON protocol mips*-*-*
5298 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5299 PowerPC with SDS protocol powerpc{,le}-*-eabi
5300 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5304 All configurations can now understand and use the DWARF 2 debugging
5305 format. The choice is automatic, if the symbol file contains DWARF 2
5310 GDB now includes basic Java language support. This support is
5311 only useful with Java compilers that produce native machine code.
5313 * solib-absolute-prefix and solib-search-path
5315 For SunOS and SVR4 shared libraries, you may now set the prefix for
5316 loading absolute shared library symbol files, and the search path for
5317 locating non-absolute shared library symbol files.
5319 * Live range splitting
5321 GDB can now effectively debug code for which GCC has performed live
5322 range splitting as part of its optimization. See gdb/doc/LRS for
5323 more details on the expected format of the stabs information.
5327 GDB's support for the GNU Hurd, including thread debugging, has been
5328 updated to work with current versions of the Hurd.
5332 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5333 instruction set. ARM GDB automatically detects when Thumb
5334 instructions are in use, and adjusts disassembly and backtracing
5339 GDB's MIPS target configurations now handle the MIP16 16-bit
5344 GDB now includes support for overlays; if an executable has been
5345 linked such that multiple sections are based at the same address, GDB
5346 will decide which section to use for symbolic info. You can choose to
5347 control the decision manually, using overlay commands, or implement
5348 additional target-side support and use "overlay load-target" to bring
5349 in the overlay mapping. Do "help overlay" for more detail.
5353 The command "info symbol <address>" displays information about
5354 the symbol at the specified address.
5358 The standard remote protocol now includes an extension that allows
5359 asynchronous collection and display of trace data. This requires
5360 extensive support in the target-side debugging stub. Tracing mode
5361 includes a new interaction mode in GDB and new commands: see the
5362 file tracepoint.c for more details.
5366 Configurations for embedded MIPS now include a simulator contributed
5367 by Cygnus Solutions. The simulator supports the instruction sets
5368 of most MIPS variants.
5372 Sparc configurations may now include the ERC32 simulator contributed
5373 by the European Space Agency. The simulator is not built into
5374 Sparc targets by default; configure with --enable-sim to include it.
5378 For target configurations that may include multiple variants of a
5379 basic architecture (such as MIPS and SH), you may now set the
5380 architecture explicitly. "set arch" sets, "info arch" lists
5381 the possible architectures.
5383 *** Changes in GDB-4.16:
5385 * New native configurations
5387 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5388 M68K NetBSD m68k-*-netbsd*
5389 PowerPC AIX 4.x powerpc-*-aix*
5390 PowerPC MacOS powerpc-*-macos*
5391 PowerPC Windows NT powerpcle-*-cygwin32
5392 RS/6000 AIX 4.x rs6000-*-aix4*
5396 ARM with RDP protocol arm-*-*
5397 I960 with MON960 i960-*-coff
5398 MIPS VxWorks mips*-*-vxworks*
5399 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5400 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5402 Matra Sparclet sparclet-*-*
5406 The powerpc-eabi configuration now includes the PSIM simulator,
5407 contributed by Andrew Cagney, with assistance from Mike Meissner.
5408 PSIM is a very elaborate model of the PowerPC, including not only
5409 basic instruction set execution, but also details of execution unit
5410 performance and I/O hardware. See sim/ppc/README for more details.
5414 GDB now works with Solaris 2.5.
5416 * Windows 95/NT native
5418 GDB will now work as a native debugger on Windows 95 and Windows NT.
5419 To build it from source, you must use the "gnu-win32" environment,
5420 which uses a DLL to emulate enough of Unix to run the GNU tools.
5421 Further information, binaries, and sources are available at
5422 ftp.cygnus.com, under pub/gnu-win32.
5424 * dont-repeat command
5426 If a user-defined command includes the command `dont-repeat', then the
5427 command will not be repeated if the user just types return. This is
5428 useful if the command is time-consuming to run, so that accidental
5429 extra keystrokes don't run the same command many times.
5431 * Send break instead of ^C
5433 The standard remote protocol now includes an option to send a break
5434 rather than a ^C to the target in order to interrupt it. By default,
5435 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5437 * Remote protocol timeout
5439 The standard remote protocol includes a new variable `remotetimeout'
5440 that allows you to set the number of seconds before GDB gives up trying
5441 to read from the target. The default value is 2.
5443 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5445 By default GDB will automatically keep track of objects as they are
5446 loaded and unloaded by the dynamic linker. By using the command `set
5447 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5448 when shared library events occur, thus allowing you to set breakpoints
5449 in shared libraries which are explicitly loaded by the inferior.
5451 Note this feature does not work on hpux8. On hpux9 you must link
5452 /usr/lib/end.o into your program. This feature should work
5453 automatically on hpux10.
5455 * Irix 5.x hardware watchpoint support
5457 Irix 5 configurations now support the use of hardware watchpoints.
5459 * Mips protocol "SYN garbage limit"
5461 When debugging a Mips target using the `target mips' protocol, you
5462 may set the number of characters that GDB will ignore by setting
5463 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5464 every character. The default value is 1050.
5466 * Recording and replaying remote debug sessions
5468 If you set `remotelogfile' to the name of a file, gdb will write to it
5469 a recording of a remote debug session. This recording may then be
5470 replayed back to gdb using "gdbreplay". See gdbserver/README for
5471 details. This is useful when you have a problem with GDB while doing
5472 remote debugging; you can make a recording of the session and send it
5473 to someone else, who can then recreate the problem.
5475 * Speedups for remote debugging
5477 GDB includes speedups for downloading and stepping MIPS systems using
5478 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5479 and more efficient S-record downloading.
5481 * Memory use reductions and statistics collection
5483 GDB now uses less memory and reports statistics about memory usage.
5484 Try the `maint print statistics' command, for example.
5486 *** Changes in GDB-4.15:
5488 * Psymtabs for XCOFF
5490 The symbol reader for AIX GDB now uses partial symbol tables. This
5491 can greatly improve startup time, especially for large executables.
5493 * Remote targets use caching
5495 Remote targets now use a data cache to speed up communication with the
5496 remote side. The data cache could lead to incorrect results because
5497 it doesn't know about volatile variables, thus making it impossible to
5498 debug targets which use memory mapped I/O devices. `set remotecache
5499 off' turns the the data cache off.
5501 * Remote targets may have threads
5503 The standard remote protocol now includes support for multiple threads
5504 in the target system, using new protocol commands 'H' and 'T'. See
5505 gdb/remote.c for details.
5509 If GDB is configured with `--enable-netrom', then it will include
5510 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5511 acts as though it is a bank of ROM on the target board, but you can
5512 write into it over the network. GDB's support consists only of
5513 support for fast loading into the emulated ROM; to debug, you must use
5514 another protocol, such as standard remote protocol. The usual
5515 sequence is something like
5517 target nrom <netrom-hostname>
5519 target remote <netrom-hostname>:1235
5523 GDB now includes support for the Apple Macintosh, as a host only. It
5524 may be run as either an MPW tool or as a standalone application, and
5525 it can debug through the serial port. All the usual GDB commands are
5526 available, but to the target command, you must supply "serial" as the
5527 device type instead of "/dev/ttyXX". See mpw-README in the main
5528 directory for more information on how to build. The MPW configuration
5529 scripts */mpw-config.in support only a few targets, and only the
5530 mips-idt-ecoff target has been tested.
5534 GDB configuration now uses autoconf. This is not user-visible,
5535 but does simplify configuration and building.
5539 GDB now supports hpux10.
5541 *** Changes in GDB-4.14:
5543 * New native configurations
5545 x86 FreeBSD i[345]86-*-freebsd
5546 x86 NetBSD i[345]86-*-netbsd
5547 NS32k NetBSD ns32k-*-netbsd
5548 Sparc NetBSD sparc-*-netbsd
5552 A29K VxWorks a29k-*-vxworks
5553 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5554 CPU32 EST-300 emulator m68*-*-est*
5555 PowerPC ELF powerpc-*-elf
5558 * Alpha OSF/1 support for procfs
5560 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5561 possible to attach to running processes. As the mounting of the /proc
5562 filesystem is optional on the Alpha, GDB automatically determines
5563 the availability of /proc during startup. This can lead to problems
5564 if /proc is unmounted after GDB has been started.
5566 * Arguments to user-defined commands
5568 User commands may accept up to 10 arguments separated by whitespace.
5569 Arguments are accessed within the user command via $arg0..$arg9. A
5572 print $arg0 + $arg1 + $arg2
5574 To execute the command use:
5577 Defines the command "adder" which prints the sum of its three arguments.
5578 Note the arguments are text substitutions, so they may reference variables,
5579 use complex expressions, or even perform inferior function calls.
5581 * New `if' and `while' commands
5583 This makes it possible to write more sophisticated user-defined
5584 commands. Both commands take a single argument, which is the
5585 expression to evaluate, and must be followed by the commands to
5586 execute, one per line, if the expression is nonzero, the list being
5587 terminated by the word `end'. The `if' command list may include an
5588 `else' word, which causes the following commands to be executed only
5589 if the expression is zero.
5591 * Fortran source language mode
5593 GDB now includes partial support for Fortran 77. It will recognize
5594 Fortran programs and can evaluate a subset of Fortran expressions, but
5595 variables and functions may not be handled correctly. GDB will work
5596 with G77, but does not yet know much about symbols emitted by other
5599 * Better HPUX support
5601 Most debugging facilities now work on dynamic executables for HPPAs
5602 running hpux9 or later. You can attach to running dynamically linked
5603 processes, but by default the dynamic libraries will be read-only, so
5604 for instance you won't be able to put breakpoints in them. To change
5605 that behavior do the following before running the program:
5611 This will cause the libraries to be mapped private and read-write.
5612 To revert to the normal behavior, do this:
5618 You cannot set breakpoints or examine data in the library until after
5619 the library is loaded if the function/data symbols do not have
5622 GDB can now also read debug symbols produced by the HP C compiler on
5623 HPPAs (sorry, no C++, Fortran or 68k support).
5625 * Target byte order now dynamically selectable
5627 You can choose which byte order to use with a target system, via the
5628 commands "set endian big" and "set endian little", and you can see the
5629 current setting by using "show endian". You can also give the command
5630 "set endian auto", in which case GDB will use the byte order
5631 associated with the executable. Currently, only embedded MIPS
5632 configurations support dynamic selection of target byte order.
5634 * New DOS host serial code
5636 This version uses DPMI interrupts to handle buffered I/O, so you
5637 no longer need to run asynctsr when debugging boards connected to
5640 *** Changes in GDB-4.13:
5642 * New "complete" command
5644 This lists all the possible completions for the rest of the line, if it
5645 were to be given as a command itself. This is intended for use by emacs.
5647 * Trailing space optional in prompt
5649 "set prompt" no longer adds a space for you after the prompt you set. This
5650 allows you to set a prompt which ends in a space or one that does not.
5652 * Breakpoint hit counts
5654 "info break" now displays a count of the number of times the breakpoint
5655 has been hit. This is especially useful in conjunction with "ignore"; you
5656 can ignore a large number of breakpoint hits, look at the breakpoint info
5657 to see how many times the breakpoint was hit, then run again, ignoring one
5658 less than that number, and this will get you quickly to the last hit of
5661 * Ability to stop printing at NULL character
5663 "set print null-stop" will cause GDB to stop printing the characters of
5664 an array when the first NULL is encountered. This is useful when large
5665 arrays actually contain only short strings.
5667 * Shared library breakpoints
5669 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5670 breakpoints in shared libraries before the executable is run.
5672 * Hardware watchpoints
5674 There is a new hardware breakpoint for the watch command for sparclite
5675 targets. See gdb/sparclite/hw_breakpoint.note.
5677 Hardware watchpoints are also now supported under GNU/Linux.
5681 Annotations have been added. These are for use with graphical interfaces,
5682 and are still experimental. Currently only gdba.el uses these.
5684 * Improved Irix 5 support
5686 GDB now works properly with Irix 5.2.
5688 * Improved HPPA support
5690 GDB now works properly with the latest GCC and GAS.
5692 * New native configurations
5694 Sequent PTX4 i[34]86-sequent-ptx4
5695 HPPA running OSF/1 hppa*-*-osf*
5696 Atari TT running SVR4 m68*-*-sysv4*
5697 RS/6000 LynxOS rs6000-*-lynxos*
5701 OS/9000 i[34]86-*-os9k
5702 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5705 * Hitachi SH7000 and E7000-PC ICE support
5707 There is now support for communicating with the Hitachi E7000-PC ICE.
5708 This is available automatically when GDB is configured for the SH.
5712 As usual, a variety of small fixes and improvements, both generic
5713 and configuration-specific. See the ChangeLog for more detail.
5715 *** Changes in GDB-4.12:
5717 * Irix 5 is now supported
5721 GDB-4.12 on the HPPA has a number of changes which make it unable
5722 to debug the output from the currently released versions of GCC and
5723 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5724 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5725 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5728 *** Changes in GDB-4.11:
5730 * User visible changes:
5734 The "set remotedebug" option is now consistent between the mips remote
5735 target, remote targets using the gdb-specific protocol, UDI (AMD's
5736 debug protocol for the 29k) and the 88k bug monitor. It is now an
5737 integer specifying a debug level (normally 0 or 1, but 2 means more
5738 debugging info for the mips target).
5740 * DEC Alpha native support
5742 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5743 debug info, but GDB works fairly well with the DEC compiler and should
5744 work with a future GCC release. See the README file for a few
5745 Alpha-specific notes.
5747 * Preliminary thread implementation
5749 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5751 * LynxOS native and target support for 386
5753 This release has been hosted on LynxOS 2.2, and also can be configured
5754 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5757 * Improvements in C++ mangling/demangling.
5759 This release has much better g++ debugging, specifically in name
5760 mangling/demangling, virtual function calls, print virtual table,
5761 call methods, ...etc.
5763 *** Changes in GDB-4.10:
5765 * User visible changes:
5767 Remote debugging using the GDB-specific (`target remote') protocol now
5768 supports the `load' command. This is only useful if you have some
5769 other way of getting the stub to the target system, and you can put it
5770 somewhere in memory where it won't get clobbered by the download.
5772 Filename completion now works.
5774 When run under emacs mode, the "info line" command now causes the
5775 arrow to point to the line specified. Also, "info line" prints
5776 addresses in symbolic form (as well as hex).
5778 All vxworks based targets now support a user settable option, called
5779 vxworks-timeout. This option represents the number of seconds gdb
5780 should wait for responses to rpc's. You might want to use this if
5781 your vxworks target is, perhaps, a slow software simulator or happens
5782 to be on the far side of a thin network line.
5786 This release contains support for using a DEC alpha as a GDB host for
5787 cross debugging. Native alpha debugging is not supported yet.
5790 *** Changes in GDB-4.9:
5794 This is the first GDB release which is accompanied by a matching testsuite.
5795 The testsuite requires installation of dejagnu, which should be available
5796 via ftp from most sites that carry GNU software.
5800 'Cfront' style demangling has had its name changed to 'ARM' style, to
5801 emphasize that it was written from the specifications in the C++ Annotated
5802 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5803 disclaimers, it still generated too much confusion with users attempting to
5804 use gdb with AT&T cfront.
5808 GDB now uses a standard remote interface to a simulator library.
5809 So far, the library contains simulators for the Zilog Z8001/2, the
5810 Hitachi H8/300, H8/500 and Super-H.
5812 * New targets supported
5814 H8/300 simulator h8300-hitachi-hms or h8300hms
5815 H8/500 simulator h8500-hitachi-hms or h8500hms
5816 SH simulator sh-hitachi-hms or sh
5817 Z8000 simulator z8k-zilog-none or z8ksim
5818 IDT MIPS board over serial line mips-idt-ecoff
5820 Cross-debugging to GO32 targets is supported. It requires a custom
5821 version of the i386-stub.c module which is integrated with the
5822 GO32 memory extender.
5824 * New remote protocols
5826 MIPS remote debugging protocol.
5828 * New source languages supported
5830 This version includes preliminary support for Chill, a Pascal like language
5831 used by telecommunications companies. Chill support is also being integrated
5832 into the GNU compiler, but we don't know when it will be publically available.
5835 *** Changes in GDB-4.8:
5837 * HP Precision Architecture supported
5839 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5840 version of this support was available as a set of patches from the
5841 University of Utah. GDB does not support debugging of programs
5842 compiled with the HP compiler, because HP will not document their file
5843 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5844 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5846 Many problems in the preliminary version have been fixed.
5848 * Faster and better demangling
5850 We have improved template demangling and fixed numerous bugs in the GNU style
5851 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5852 character types (wchar_t) are now supported. Demangling of each symbol is now
5853 only done once, and is cached when the symbol table for a file is read in.
5854 This results in a small increase in memory usage for C programs, a moderate
5855 increase in memory usage for C++ programs, and a fantastic speedup in
5858 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5859 from the specifications in the Annotated Reference Manual, which AT&T's
5860 compiler does not actually implement.
5862 * G++ multiple inheritance compiler problem
5864 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5865 inheritance lattices was reworked to properly discover ambiguities. We
5866 recently found an example which causes this new algorithm to fail in a
5867 very subtle way, producing bad debug information for those classes.
5868 The file 'gcc.patch' (in this directory) can be applied to gcc to
5869 circumvent the problem. A future GCC release will contain a complete
5872 The previous G++ debug info problem (mentioned below for the gdb-4.7
5873 release) is fixed in gcc version 2.3.2.
5875 * Improved configure script
5877 The `configure' script will now attempt to guess your system type if
5878 you don't supply a host system type. The old scheme of supplying a
5879 host system triplet is preferable over using this. All the magic is
5880 done in the new `config.guess' script. Examine it for details.
5882 We have also brought our configure script much more in line with the FSF's
5883 version. It now supports the --with-xxx options. In particular,
5884 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5885 The resulting GDB will not be able to read arbitrary object file formats --
5886 only the format ``expected'' to be used on the configured target system.
5887 We hope to make this the default in a future release.
5889 * Documentation improvements
5891 There's new internal documentation on how to modify GDB, and how to
5892 produce clean changes to the code. We implore people to read it
5893 before submitting changes.
5895 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5896 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5897 `info' files are also provided. To build `info' files from scratch,
5898 you will need the latest `makeinfo' release, which will be available in
5899 a future texinfo-X.Y release.
5901 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5902 We're not sure exactly which versions have this problem, but it has
5903 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5904 or better. If that isn't possible, there is a patch in
5905 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5906 around this problem.
5910 GDB now supports array constants that can be used in expressions typed in by
5911 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5912 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5915 The new directory `gdb/sparclite' contains a program that demonstrates
5916 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5918 * New native hosts supported
5920 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5921 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5923 * New targets supported
5925 AMD 29k family via UDI a29k-amd-udi or udi29k
5927 * New file formats supported
5929 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5930 HPUX core files, and SCO 3.2v2 core files.
5934 Attaching to processes now works again; thanks for the many bug reports.
5936 We have also stomped on a bunch of core dumps caused by
5937 printf_filtered("%s") problems.
5939 We eliminated a copyright problem on the rpc and ptrace header files
5940 for VxWorks, which was discovered at the last minute during the 4.7
5941 release. You should now be able to build a VxWorks GDB.
5943 You can now interrupt gdb while an attached process is running. This
5944 will cause the attached process to stop, and give control back to GDB.
5946 We fixed problems caused by using too many file descriptors
5947 for reading symbols from object files and libraries. This was
5948 especially a problem for programs that used many (~100) shared
5951 The `step' command now only enters a subroutine if there is line number
5952 information for the subroutine. Otherwise it acts like the `next'
5953 command. Previously, `step' would enter subroutines if there was
5954 any debugging information about the routine. This avoids problems
5955 when using `cc -g1' on MIPS machines.
5957 * Internal improvements
5959 GDB's internal interfaces have been improved to make it easier to support
5960 debugging of multiple languages in the future.
5962 GDB now uses a common structure for symbol information internally.
5963 Minimal symbols (derived from linkage symbols in object files), partial
5964 symbols (from a quick scan of debug information), and full symbols
5965 contain a common subset of information, making it easier to write
5966 shared code that handles any of them.
5968 * New command line options
5970 We now accept --silent as an alias for --quiet.
5974 The memory-mapped-malloc library is now licensed under the GNU Library
5975 General Public License.
5977 *** Changes in GDB-4.7:
5979 * Host/native/target split
5981 GDB has had some major internal surgery to untangle the support for
5982 hosts and remote targets. Now, when you configure GDB for a remote
5983 target, it will no longer load in all of the support for debugging
5984 local programs on the host. When fully completed and tested, this will
5985 ensure that arbitrary host/target combinations are possible.
5987 The primary conceptual shift is to separate the non-portable code in
5988 GDB into three categories. Host specific code is required any time GDB
5989 is compiled on that host, regardless of the target. Target specific
5990 code relates to the peculiarities of the target, but can be compiled on
5991 any host. Native specific code is everything else: it can only be
5992 built when the host and target are the same system. Child process
5993 handling and core file support are two common `native' examples.
5995 GDB's use of /proc for controlling Unix child processes is now cleaner.
5996 It has been split out into a single module under the `target_ops' vector,
5997 plus two native-dependent functions for each system that uses /proc.
5999 * New hosts supported
6001 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6002 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6003 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6005 * New targets supported
6007 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6008 68030 and CPU32 m68030-*-*, m68332-*-*
6010 * New native hosts supported
6012 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6013 (386bsd is not well tested yet)
6014 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6016 * New file formats supported
6018 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6019 supports reading of `a.out.adobe' object files, which are an a.out
6020 format extended with minimal information about multiple sections.
6024 `show copying' is the same as the old `info copying'.
6025 `show warranty' is the same as `info warrantee'.
6026 These were renamed for consistency. The old commands continue to work.
6028 `info handle' is a new alias for `info signals'.
6030 You can now define pre-command hooks, which attach arbitrary command
6031 scripts to any command. The commands in the hook will be executed
6032 prior to the user's command. You can also create a hook which will be
6033 executed whenever the program stops. See gdb.texinfo.
6037 We now deal with Cfront style name mangling, and can even extract type
6038 info from mangled symbols. GDB can automatically figure out which
6039 symbol mangling style your C++ compiler uses.
6041 Calling of methods and virtual functions has been improved as well.
6045 The crash that occured when debugging Sun Ansi-C compiled binaries is
6046 fixed. This was due to mishandling of the extra N_SO stabs output
6049 We also finally got Ultrix 4.2 running in house, and fixed core file
6050 support, with help from a dozen people on the net.
6052 John M. Farrell discovered that the reason that single-stepping was so
6053 slow on all of the Mips based platforms (primarily SGI and DEC) was
6054 that we were trying to demangle and lookup a symbol used for internal
6055 purposes on every instruction that was being stepped through. Changing
6056 the name of that symbol so that it couldn't be mistaken for a C++
6057 mangled symbol sped things up a great deal.
6059 Rich Pixley sped up symbol lookups in general by getting much smarter
6060 about when C++ symbol mangling is necessary. This should make symbol
6061 completion (TAB on the command line) much faster. It's not as fast as
6062 we'd like, but it's significantly faster than gdb-4.6.
6066 A new user controllable variable 'call_scratch_address' can
6067 specify the location of a scratch area to be used when GDB
6068 calls a function in the target. This is necessary because the
6069 usual method of putting the scratch area on the stack does not work
6070 in systems that have separate instruction and data spaces.
6072 We integrated changes to support the 29k UDI (Universal Debugger
6073 Interface), but discovered at the last minute that we didn't have all
6074 of the appropriate copyright paperwork. We are working with AMD to
6075 resolve this, and hope to have it available soon.
6079 We have sped up the remote serial line protocol, especially for targets
6080 with lots of registers. It now supports a new `expedited status' ('T')
6081 message which can be used in place of the existing 'S' status message.
6082 This allows the remote stub to send only the registers that GDB
6083 needs to make a quick decision about single-stepping or conditional
6084 breakpoints, eliminating the need to fetch the entire register set for
6085 each instruction being stepped through.
6087 The GDB remote serial protocol now implements a write-through cache for
6088 registers, only re-reading the registers if the target has run.
6090 There is also a new remote serial stub for SPARC processors. You can
6091 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6092 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6093 processor with a serial port.
6097 Configure.in files have become much easier to read and modify. A new
6098 `table driven' format makes it more obvious what configurations are
6099 supported, and what files each one uses.
6103 There is a new opcodes library which will eventually contain all of the
6104 disassembly routines and opcode tables. At present, it only contains
6105 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6106 disassembler (binutils/objdump) to share these routines.
6108 The libiberty library is now copylefted under the GNU Library General
6109 Public License. This allows more liberal use, and was done so libg++
6110 can use it. This makes no difference to GDB, since the Library License
6111 grants all the rights from the General Public License.
6115 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6116 reference to the stabs symbol info used by the debugger. It is (as far
6117 as we know) the only published document on this fascinating topic. We
6118 encourage you to read it, compare it to the stabs information on your
6119 system, and send improvements on the document in general (to
6120 bug-gdb@prep.ai.mit.edu).
6122 And, of course, many bugs have been fixed.
6125 *** Changes in GDB-4.6:
6127 * Better support for C++ function names
6129 GDB now accepts as input the "demangled form" of C++ overloaded function
6130 names and member function names, and can do command completion on such names
6131 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6132 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6133 Make use of command completion, it is your friend.
6135 GDB also now accepts a variety of C++ mangled symbol formats. They are
6136 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6137 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6138 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6139 for the list of formats.
6141 * G++ symbol mangling problem
6143 Recent versions of gcc have a bug in how they emit debugging information for
6144 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6145 directory) can be applied to gcc to fix the problem. Alternatively, if you
6146 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6147 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6148 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6151 * New 'maintenance' command
6153 All of the commands related to hacking GDB internals have been moved out of
6154 the main command set, and now live behind the 'maintenance' command. This
6155 can also be abbreviated as 'mt'. The following changes were made:
6157 dump-me -> maintenance dump-me
6158 info all-breakpoints -> maintenance info breakpoints
6159 printmsyms -> maintenance print msyms
6160 printobjfiles -> maintenance print objfiles
6161 printpsyms -> maintenance print psymbols
6162 printsyms -> maintenance print symbols
6164 The following commands are new:
6166 maintenance demangle Call internal GDB demangler routine to
6167 demangle a C++ link name and prints the result.
6168 maintenance print type Print a type chain for a given symbol
6170 * Change to .gdbinit file processing
6172 We now read the $HOME/.gdbinit file before processing the argv arguments
6173 (e.g. reading symbol files or core files). This allows global parameters to
6174 be set, which will apply during the symbol reading. The ./.gdbinit is still
6175 read after argv processing.
6177 * New hosts supported
6179 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6181 GNU/Linux support i386-unknown-linux or linux
6183 We are also including code to support the HP/PA running BSD and HPUX. This
6184 is almost guaranteed not to work, as we didn't have time to test or build it
6185 for this release. We are including it so that the more adventurous (or
6186 masochistic) of you can play with it. We also had major problems with the
6187 fact that the compiler that we got from HP doesn't support the -g option.
6190 * New targets supported
6192 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6194 * More smarts about finding #include files
6196 GDB now remembers the compilation directory for all include files, and for
6197 all files from which C is generated (like yacc and lex sources). This
6198 greatly improves GDB's ability to find yacc/lex sources, and include files,
6199 especially if you are debugging your program from a directory different from
6200 the one that contains your sources.
6202 We also fixed a bug which caused difficulty with listing and setting
6203 breakpoints in include files which contain C code. (In the past, you had to
6204 try twice in order to list an include file that you hadn't looked at before.)
6206 * Interesting infernals change
6208 GDB now deals with arbitrary numbers of sections, where the symbols for each
6209 section must be relocated relative to that section's landing place in the
6210 target's address space. This work was needed to support ELF with embedded
6211 stabs used by Solaris-2.0.
6213 * Bug fixes (of course!)
6215 There have been loads of fixes for the following things:
6216 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6217 i960, stabs, DOS(GO32), procfs, etc...
6219 See the ChangeLog for details.
6221 *** Changes in GDB-4.5:
6223 * New machines supported (host and target)
6225 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6227 SGI Irix-4.x mips-sgi-irix4 or iris4
6229 * New malloc package
6231 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6232 Mmalloc is capable of handling mutiple heaps of memory. It is also
6233 capable of saving a heap to a file, and then mapping it back in later.
6234 This can be used to greatly speedup the startup of GDB by using a
6235 pre-parsed symbol table which lives in a mmalloc managed heap. For
6236 more details, please read mmalloc/mmalloc.texi.
6240 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6241 'help info proc' for details.
6243 * MIPS ecoff symbol table format
6245 The code that reads MIPS symbol table format is now supported on all hosts.
6246 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6249 * File name changes for MS-DOS
6251 Many files in the config directories have been renamed to make it easier to
6252 support GDB on MS-DOSe systems (which have very restrictive file name
6253 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6254 environment) is close to working but has some remaining problems. Note
6255 that debugging of DOS programs is not supported, due to limitations
6256 in the ``operating system'', but it can be used to host cross-debugging.
6258 * Cross byte order fixes
6260 Many fixes have been made to support cross debugging of Sparc and MIPS
6261 targets from hosts whose byte order differs.
6263 * New -mapped and -readnow options
6265 If memory-mapped files are available on your system through the 'mmap'
6266 system call, you can use the -mapped option on the `file' or
6267 `symbol-file' commands to cause GDB to write the symbols from your
6268 program into a reusable file. If the program you are debugging is
6269 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6270 Future GDB debugging sessions will notice the presence of this file,
6271 and will quickly map in symbol information from it, rather than reading
6272 the symbol table from the executable program. Using the '-mapped'
6273 option in a GDB `file' or `symbol-file' command has the same effect as
6274 starting GDB with the '-mapped' command-line option.
6276 You can cause GDB to read the entire symbol table immediately by using
6277 the '-readnow' option with any of the commands that load symbol table
6278 information (or on the GDB command line). This makes the command
6279 slower, but makes future operations faster.
6281 The -mapped and -readnow options are typically combined in order to
6282 build a `fred.syms' file that contains complete symbol information.
6283 A simple GDB invocation to do nothing but build a `.syms' file for future
6286 gdb -batch -nx -mapped -readnow programname
6288 The `.syms' file is specific to the host machine on which GDB is run.
6289 It holds an exact image of GDB's internal symbol table. It cannot be
6290 shared across multiple host platforms.
6292 * longjmp() handling
6294 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6295 siglongjmp() without losing control. This feature has not yet been ported to
6296 all systems. It currently works on many 386 platforms, all MIPS-based
6297 platforms (SGI, DECstation, etc), and Sun3/4.
6301 Preliminary work has been put in to support the new Solaris OS from Sun. At
6302 this time, it can control and debug processes, but it is not capable of
6307 As always, many many bug fixes. The major areas were with g++, and mipsread.
6308 People using the MIPS-based platforms should experience fewer mysterious
6309 crashes and trashed symbol tables.
6311 *** Changes in GDB-4.4:
6313 * New machines supported (host and target)
6315 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6317 BSD Reno on Vax vax-dec-bsd
6318 Ultrix on Vax vax-dec-ultrix
6320 * New machines supported (target)
6322 AMD 29000 embedded, using EBMON a29k-none-none
6326 GDB continues to improve its handling of C++. `References' work better.
6327 The demangler has also been improved, and now deals with symbols mangled as
6328 per the Annotated C++ Reference Guide.
6330 GDB also now handles `stabs' symbol information embedded in MIPS
6331 `ecoff' symbol tables. Since the ecoff format was not easily
6332 extensible to handle new languages such as C++, this appeared to be a
6333 good way to put C++ debugging info into MIPS binaries. This option
6334 will be supported in the GNU C compiler, version 2, when it is
6337 * New features for SVR4
6339 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6340 shared libraries. Debugging dynamically linked programs should present
6341 only minor differences from debugging statically linked programs.
6343 The `info proc' command will print out information about any process
6344 on an SVR4 system (including the one you are debugging). At the moment,
6345 it prints the address mappings of the process.
6347 If you bring up GDB on another SVR4 system, please send mail to
6348 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6350 * Better dynamic linking support in SunOS
6352 Reading symbols from shared libraries which contain debugging symbols
6353 now works properly. However, there remain issues such as automatic
6354 skipping of `transfer vector' code during function calls, which
6355 make it harder to debug code in a shared library, than to debug the
6356 same code linked statically.
6360 GDB is now using the latest `getopt' routines from the FSF. This
6361 version accepts the -- prefix for options with long names. GDB will
6362 continue to accept the old forms (-option and +option) as well.
6363 Various single letter abbreviations for options have been explicity
6364 added to the option table so that they won't get overshadowed in the
6365 future by other options that begin with the same letter.
6369 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6370 Many assorted bugs have been handled. Many more remain to be handled.
6371 See the various ChangeLog files (primarily in gdb and bfd) for details.
6374 *** Changes in GDB-4.3:
6376 * New machines supported (host and target)
6378 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6379 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6380 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6382 * Almost SCO Unix support
6384 We had hoped to support:
6385 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6386 (except for core file support), but we discovered very late in the release
6387 that it has problems with process groups that render gdb unusable. Sorry
6388 about that. I encourage people to fix it and post the fixes.
6390 * Preliminary ELF and DWARF support
6392 GDB can read ELF object files on System V Release 4, and can handle
6393 debugging records for C, in DWARF format, in ELF files. This support
6394 is preliminary. If you bring up GDB on another SVR4 system, please
6395 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6400 GDB now uses the latest `readline' library. One user-visible change
6401 is that two tabs will list possible command completions, which previously
6402 required typing M-? (meta-question mark, or ESC ?).
6406 The `stepi' bug that many of you noticed has been squashed.
6407 Many bugs in C++ have been handled. Many more remain to be handled.
6408 See the various ChangeLog files (primarily in gdb and bfd) for details.
6410 * State of the MIPS world (in case you wondered):
6412 GDB can understand the symbol tables emitted by the compilers
6413 supplied by most vendors of MIPS-based machines, including DEC. These
6414 symbol tables are in a format that essentially nobody else uses.
6416 Some versions of gcc come with an assembler post-processor called
6417 mips-tfile. This program is required if you want to do source-level
6418 debugging of gcc-compiled programs. I believe FSF does not ship
6419 mips-tfile with gcc version 1, but it will eventually come with gcc
6422 Debugging of g++ output remains a problem. g++ version 1.xx does not
6423 really support it at all. (If you're lucky, you should be able to get
6424 line numbers and stack traces to work, but no parameters or local
6425 variables.) With some work it should be possible to improve the
6428 When gcc version 2 is released, you will have somewhat better luck.
6429 However, even then you will get confusing results for inheritance and
6432 We will eventually provide full debugging of g++ output on
6433 DECstations. This will probably involve some kind of stabs-in-ecoff
6434 encapulation, but the details have not been worked out yet.
6437 *** Changes in GDB-4.2:
6439 * Improved configuration
6441 Only one copy of `configure' exists now, and it is not self-modifying.
6442 Porting BFD is simpler.
6446 The `step' and `next' commands now only stop at the first instruction
6447 of a source line. This prevents the multiple stops that used to occur
6448 in switch statements, for-loops, etc. `Step' continues to stop if a
6449 function that has debugging information is called within the line.
6453 Lots of small bugs fixed. More remain.
6455 * New host supported (not target)
6457 Intel 386 PC clone running Mach i386-none-mach
6460 *** Changes in GDB-4.1:
6462 * Multiple source language support
6464 GDB now has internal scaffolding to handle several source languages.
6465 It determines the type of each source file from its filename extension,
6466 and will switch expression parsing and number formatting to match the
6467 language of the function in the currently selected stack frame.
6468 You can also specifically set the language to be used, with
6469 `set language c' or `set language modula-2'.
6473 GDB now has preliminary support for the GNU Modula-2 compiler,
6474 currently under development at the State University of New York at
6475 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6476 continue through the fall of 1991 and into 1992.
6478 Other Modula-2 compilers are currently not supported, and attempting to
6479 debug programs compiled with them will likely result in an error as the
6480 symbol table is read. Feel free to work on it, though!
6482 There are hooks in GDB for strict type checking and range checking,
6483 in the `Modula-2 philosophy', but they do not currently work.
6487 GDB can now write to executable and core files (e.g. patch
6488 a variable's value). You must turn this switch on, specify
6489 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6490 by assigning a new value to a variable. Modifications take
6493 * Automatic SunOS shared library reading
6495 When you run your program, GDB automatically determines where its
6496 shared libraries (if any) have been loaded, and reads their symbols.
6497 The `share' command is no longer needed. This also works when
6498 examining core files.
6502 You can specify the number of lines that the `list' command shows.
6505 * New machines supported (host and target)
6507 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6508 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6509 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6511 * New hosts supported (not targets)
6513 IBM RT/PC: romp-ibm-aix or rtpc
6515 * New targets supported (not hosts)
6517 AMD 29000 embedded with COFF a29k-none-coff
6518 AMD 29000 embedded with a.out a29k-none-aout
6519 Ultracomputer remote kernel debug a29k-nyu-kern
6521 * New remote interfaces
6527 *** Changes in GDB-4.0:
6531 Wide output is wrapped at good places to make the output more readable.
6533 Gdb now supports cross-debugging from a host machine of one type to a
6534 target machine of another type. Communication with the target system
6535 is over serial lines. The ``target'' command handles connecting to the
6536 remote system; the ``load'' command will download a program into the
6537 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6538 also supports debugging of realtime processes running under VxWorks,
6539 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6540 stub on the target system.
6542 New CPUs supported include the AMD 29000 and Intel 960.
6544 GDB now reads object files and symbol tables via a ``binary file''
6545 library, which allows a single copy of GDB to debug programs of multiple
6546 object file types such as a.out and coff.
6548 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6549 refcard.dvi and refcard.ps are available to format it).
6552 * Control-Variable user interface simplified
6554 All variables that control the operation of the debugger can be set
6555 by the ``set'' command, and displayed by the ``show'' command.
6557 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6558 ``Show prompt'' produces the response:
6559 Gdb's prompt is new-gdb=>.
6561 What follows are the NEW set commands. The command ``help set'' will
6562 print a complete list of old and new set commands. ``help set FOO''
6563 will give a longer description of the variable FOO. ``show'' will show
6564 all of the variable descriptions and their current settings.
6566 confirm on/off: Enables warning questions for operations that are
6567 hard to recover from, e.g. rerunning the program while
6568 it is already running. Default is ON.
6570 editing on/off: Enables EMACS style command line editing
6571 of input. Previous lines can be recalled with
6572 control-P, the current line can be edited with control-B,
6573 you can search for commands with control-R, etc.
6576 history filename NAME: NAME is where the gdb command history
6577 will be stored. The default is .gdb_history,
6578 or the value of the environment variable
6581 history size N: The size, in commands, of the command history. The
6582 default is 256, or the value of the environment variable
6585 history save on/off: If this value is set to ON, the history file will
6586 be saved after exiting gdb. If set to OFF, the
6587 file will not be saved. The default is OFF.
6589 history expansion on/off: If this value is set to ON, then csh-like
6590 history expansion will be performed on
6591 command line input. The default is OFF.
6593 radix N: Sets the default radix for input and output. It can be set
6594 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6595 in the current radix, so "set radix 10" is always a no-op.
6597 height N: This integer value is the number of lines on a page. Default
6598 is 24, the current `stty rows'' setting, or the ``li#''
6599 setting from the termcap entry matching the environment
6602 width N: This integer value is the number of characters on a line.
6603 Default is 80, the current `stty cols'' setting, or the ``co#''
6604 setting from the termcap entry matching the environment
6607 Note: ``set screensize'' is obsolete. Use ``set height'' and
6608 ``set width'' instead.
6610 print address on/off: Print memory addresses in various command displays,
6611 such as stack traces and structure values. Gdb looks
6612 more ``symbolic'' if you turn this off; it looks more
6613 ``machine level'' with it on. Default is ON.
6615 print array on/off: Prettyprint arrays. New convenient format! Default
6618 print demangle on/off: Print C++ symbols in "source" form if on,
6621 print asm-demangle on/off: Same, for assembler level printouts
6624 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6627 * Support for Epoch Environment.
6629 The epoch environment is a version of Emacs v18 with windowing. One
6630 new command, ``inspect'', is identical to ``print'', except that if you
6631 are running in the epoch environment, the value is printed in its own
6635 * Support for Shared Libraries
6637 GDB can now debug programs and core files that use SunOS shared libraries.
6638 Symbols from a shared library cannot be referenced
6639 before the shared library has been linked with the program (this
6640 happens after you type ``run'' and before the function main() is entered).
6641 At any time after this linking (including when examining core files
6642 from dynamically linked programs), gdb reads the symbols from each
6643 shared library when you type the ``sharedlibrary'' command.
6644 It can be abbreviated ``share''.
6646 sharedlibrary REGEXP: Load shared object library symbols for files
6647 matching a unix regular expression. No argument
6648 indicates to load symbols for all shared libraries.
6650 info sharedlibrary: Status of loaded shared libraries.
6655 A watchpoint stops execution of a program whenever the value of an
6656 expression changes. Checking for this slows down execution
6657 tremendously whenever you are in the scope of the expression, but is
6658 quite useful for catching tough ``bit-spreader'' or pointer misuse
6659 problems. Some machines such as the 386 have hardware for doing this
6660 more quickly, and future versions of gdb will use this hardware.
6662 watch EXP: Set a watchpoint (breakpoint) for an expression.
6664 info watchpoints: Information about your watchpoints.
6666 delete N: Deletes watchpoint number N (same as breakpoints).
6667 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6668 enable N: Re-enables watchpoint number N (same as breakpoints).
6671 * C++ multiple inheritance
6673 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6676 * C++ exception handling
6678 Gdb now supports limited C++ exception handling. Besides the existing
6679 ability to breakpoint on an exception handler, gdb can breakpoint on
6680 the raising of an exception (before the stack is peeled back to the
6683 catch FOO: If there is a FOO exception handler in the dynamic scope,
6684 set a breakpoint to catch exceptions which may be raised there.
6685 Multiple exceptions (``catch foo bar baz'') may be caught.
6687 info catch: Lists all exceptions which may be caught in the
6688 current stack frame.
6691 * Minor command changes
6693 The command ``call func (arg, arg, ...)'' now acts like the print
6694 command, except it does not print or save a value if the function's result
6695 is void. This is similar to dbx usage.
6697 The ``up'' and ``down'' commands now always print the frame they end up
6698 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6699 frames without printing.
6701 * New directory command
6703 'dir' now adds directories to the FRONT of the source search path.
6704 The path starts off empty. Source files that contain debug information
6705 about the directory in which they were compiled can be found even
6706 with an empty path; Sun CC and GCC include this information. If GDB can't
6707 find your source file in the current directory, type "dir .".
6709 * Configuring GDB for compilation
6711 For normal use, type ``./configure host''. See README or gdb.texinfo
6714 GDB now handles cross debugging. If you are remotely debugging between
6715 two different machines, type ``./configure host -target=targ''.
6716 Host is the machine where GDB will run; targ is the machine
6717 where the program that you are debugging will run.
projects / binutils-gdb.git / blob