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 *** Changes in GDB 8.0
22 * GDB now supports access to the PKU register on GNU/Linux. The register is
23 added by the Memory Protection Keys for Userspace feature which will be
24 available in future Intel CPUs.
26 * GDB now supports C++11 rvalue references.
30 ** New functions to start, stop and access a running btrace recording.
31 ** Rvalue references are now supported in gdb.Type.
33 * GDB now supports recording and replaying rdrand and rdseed Intel 64
36 * Building GDB and GDBserver now requires a C++11 compiler.
38 For example, GCC 4.8 or later.
40 It is no longer possible to build GDB or GDBserver with a C
41 compiler. The --disable-build-with-cxx configure option has been
44 * Building GDB and GDBserver now requires GNU make >= 3.81.
46 It is no longer supported to build GDB or GDBserver with another
47 implementation of the make program or an earlier version of GNU make.
49 * Native debugging on MS-Windows supports command-line redirection
51 Command-line arguments used for starting programs on MS-Windows can
52 now include redirection symbols supported by native Windows shells,
53 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
54 as "run", "start", and "set args", as well as the corresponding MI
57 * Support for thread names on MS-Windows.
59 GDB now catches and handles the special exception that programs
60 running on MS-Windows use to assign names to threads in the
63 * Support for Java programs compiled with gcj has been removed.
65 * User commands now accept an unlimited number of arguments.
66 Previously, only up to 10 was accepted.
68 * The "eval" command now expands user-defined command arguments.
70 This makes it easier to process a variable number of arguments:
75 eval "print $arg%d", $i
80 * Target descriptions can now describe registers for sparc32 and sparc64.
82 * GDB now supports DWARF version 5 (debug information format).
83 Its .debug_names index is not yet supported.
85 * New native configurations
87 FreeBSD/mips mips*-*-freebsd
91 Synopsys ARC arc*-*-elf32
92 FreeBSD/mips mips*-*-freebsd
94 * Removed targets and native configurations
96 Alpha running FreeBSD alpha*-*-freebsd*
97 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
102 Erases all the flash memory regions reported by the target.
104 maint print arc arc-instruction address
105 Print internal disassembler information about instruction at a given address.
109 set disassembler-options
110 show disassembler-options
111 Controls the passing of target specific information to the disassembler.
112 If it is necessary to specify more than one disassembler option then
113 multiple options can be placed together into a comma separated list.
114 The default value is the empty string. Currently, the only supported
115 targets are ARM, PowerPC and S/390.
120 Erases all the flash memory regions reported by the target. This is
121 equivalent to the CLI command flash-erase.
123 -file-list-shared-libraries
124 List the shared libraries in the program. This is
125 equivalent to the CLI command "info shared".
127 *** Changes in GDB 7.12
129 * GDB and GDBserver now build with a C++ compiler by default.
131 The --enable-build-with-cxx configure option is now enabled by
132 default. One must now explicitly configure with
133 --disable-build-with-cxx in order to build with a C compiler. This
134 option will be removed in a future release.
136 * GDBserver now supports recording btrace without maintaining an active
139 * GDB now supports a negative repeat count in the 'x' command to examine
140 memory backward from the given address. For example:
143 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
144 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
145 (gdb) x/-5i 0x0000000000400580
146 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
147 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
148 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
149 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
150 0x40057b <main(int, char**)+25>:
151 callq 0x400536 <Func1(int, char const*)>
153 * Fortran: Support structures with fields of dynamic types and
154 arrays of dynamic types.
156 * The symbol dumping maintenance commands have new syntax.
157 maint print symbols [-pc address] [--] [filename]
158 maint print symbols [-objfile objfile] [-source source] [--] [filename]
159 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
160 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
161 maint print msymbols [-objfile objfile] [--] [filename]
163 * GDB now supports multibit bitfields and enums in target register
166 * New Python-based convenience function $_as_string(val), which returns
167 the textual representation of a value. This function is especially
168 useful to obtain the text label of an enum value.
170 * Intel MPX bound violation handling.
172 Segmentation faults caused by a Intel MPX boundary violation
173 now display the kind of violation (upper or lower), the memory
174 address accessed and the memory bounds, along with the usual
175 signal received and code location.
179 Program received signal SIGSEGV, Segmentation fault
180 Upper bound violation while accessing address 0x7fffffffc3b3
181 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
182 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
184 * Rust language support.
185 GDB now supports debugging programs written in the Rust programming
186 language. See https://www.rust-lang.org/ for more information about
189 * Support for running interpreters on specified input/output devices
191 GDB now supports a new mechanism that allows frontends to provide
192 fully featured GDB console views, as a better alternative to
193 building such views on top of the "-interpreter-exec console"
194 command. See the new "new-ui" command below. With that command,
195 frontends can now start GDB in the traditional command-line mode
196 running in an embedded terminal emulator widget, and create a
197 separate MI interpreter running on a specified i/o device. In this
198 way, GDB handles line editing, history, tab completion, etc. in the
199 console all by itself, and the GUI uses the separate MI interpreter
200 for its own control and synchronization, invisible to the command
203 * The "catch syscall" command catches groups of related syscalls.
205 The "catch syscall" command now supports catching a group of related
206 syscalls using the 'group:' or 'g:' prefix.
211 skip -gfile file-glob-pattern
212 skip -function function
213 skip -rfunction regular-expression
214 A generalized form of the skip command, with new support for
215 glob-style file names and regular expressions for function names.
216 Additionally, a file spec and a function spec may now be combined.
218 maint info line-table REGEXP
219 Display the contents of GDB's internal line table data struture.
222 Run any GDB unit tests that were compiled in.
225 Start a new user interface instance running INTERP as interpreter,
226 using the TTY file for input/output.
230 ** gdb.Breakpoint objects have a new attribute "pending", which
231 indicates whether the breakpoint is pending.
232 ** Three new breakpoint-related events have been added:
233 gdb.breakpoint_created, gdb.breakpoint_modified, and
234 gdb.breakpoint_deleted.
237 Signal ("set") the given MS-Windows event object. This is used in
238 conjunction with the Windows JIT debugging (AeDebug) support, where
239 the OS suspends a crashing process until a debugger can attach to
240 it. Resuming the crashing process, in order to debug it, is done by
243 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
244 was added in GDBserver, including JIT compiling fast tracepoint's
245 conditional expression bytecode into native code.
247 * Support for various remote target protocols and ROM monitors has
250 target m32rsdi Remote M32R debugging over SDI
251 target mips MIPS remote debugging protocol
252 target pmon PMON ROM monitor
253 target ddb NEC's DDB variant of PMON for Vr4300
254 target rockhopper NEC RockHopper variant of PMON
255 target lsi LSI variant of PMO
257 * Support for tracepoints and fast tracepoints on powerpc-linux,
258 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
259 including JIT compiling fast tracepoint's conditional expression
260 bytecode into native code.
262 * MI async record =record-started now includes the method and format used for
263 recording. For example:
265 =record-started,thread-group="i1",method="btrace",format="bts"
267 * MI async record =thread-selected now includes the frame field. For example:
269 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
273 Andes NDS32 nds32*-*-elf
275 *** Changes in GDB 7.11
277 * GDB now supports debugging kernel-based threads on FreeBSD.
279 * Per-inferior thread numbers
281 Thread numbers are now per inferior instead of global. If you're
282 debugging multiple inferiors, GDB displays thread IDs using a
283 qualified INF_NUM.THR_NUM form. For example:
287 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
288 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
289 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
290 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
292 As consequence, thread numbers as visible in the $_thread
293 convenience variable and in Python's InferiorThread.num attribute
294 are no longer unique between inferiors.
296 GDB now maintains a second thread ID per thread, referred to as the
297 global thread ID, which is the new equivalent of thread numbers in
298 previous releases. See also $_gthread below.
300 For backwards compatibility, MI's thread IDs always refer to global
303 * Commands that accept thread IDs now accept the qualified
304 INF_NUM.THR_NUM form as well. For example:
307 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
310 * In commands that accept a list of thread IDs, you can now refer to
311 all threads of an inferior using a star wildcard. GDB accepts
312 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
313 refer to all threads of the current inferior. For example, "info
316 * You can use "info threads -gid" to display the global thread ID of
319 * The new convenience variable $_gthread holds the global number of
322 * The new convenience variable $_inferior holds the number of the
325 * GDB now displays the ID and name of the thread that hit a breakpoint
326 or received a signal, if your program is multi-threaded. For
329 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
330 Thread 1 "main" received signal SIGINT, Interrupt.
332 * Record btrace now supports non-stop mode.
334 * Support for tracepoints on aarch64-linux was added in GDBserver.
336 * The 'record instruction-history' command now indicates speculative execution
337 when using the Intel Processor Trace recording format.
339 * GDB now allows users to specify explicit locations, bypassing
340 the linespec parser. This feature is also available to GDB/MI
343 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
344 GDB now is able to debug both AArch64 applications and ARM applications
347 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
348 including JIT compiling fast tracepoint's conditional expression bytecode
351 * GDB now supports displaced stepping on AArch64 GNU/Linux.
353 * "info threads", "info inferiors", "info display", "info checkpoints"
354 and "maint info program-spaces" now list the corresponding items in
355 ascending ID order, for consistency with all other "info" commands.
357 * In Ada, the overloads selection menu has been enhanced to display the
358 parameter types and the return types for the matching overloaded subprograms.
362 maint set target-non-stop (on|off|auto)
363 maint show target-non-stop
364 Control whether GDB targets always operate in non-stop mode even if
365 "set non-stop" is "off". The default is "auto", meaning non-stop
366 mode is enabled if supported by the target.
368 maint set bfd-sharing
369 maint show bfd-sharing
370 Control the reuse of bfd objects.
374 Control display of debugging info regarding bfd caching.
378 Control display of debugging info regarding FreeBSD threads.
380 set remote multiprocess-extensions-packet
381 show remote multiprocess-extensions-packet
382 Set/show the use of the remote protocol multiprocess extensions.
384 set remote thread-events
385 show remote thread-events
386 Set/show the use of thread create/exit events.
388 set ada print-signatures on|off
389 show ada print-signatures"
390 Control whether parameter types and return types are displayed in overloads
391 selection menus. It is activaled (@code{on}) by default.
395 Controls the maximum size of memory, in bytes, that GDB will
396 allocate for value contents. Prevents incorrect programs from
397 causing GDB to allocate overly large buffers. Default is 64k.
399 * The "disassemble" command accepts a new modifier: /s.
400 It prints mixed source+disassembly like /m with two differences:
401 - disassembled instructions are now printed in program order, and
402 - and source for all relevant files is now printed.
403 The "/m" option is now considered deprecated: its "source-centric"
404 output hasn't proved useful in practice.
406 * The "record instruction-history" command accepts a new modifier: /s.
407 It behaves exactly like /m and prints mixed source+disassembly.
409 * The "set scheduler-locking" command supports a new mode "replay".
410 It behaves like "off" in record mode and like "on" in replay mode.
412 * Support for various ROM monitors has been removed:
414 target dbug dBUG ROM monitor for Motorola ColdFire
415 target picobug Motorola picobug monitor
416 target dink32 DINK32 ROM monitor for PowerPC
417 target m32r Renesas M32R/D ROM monitor
418 target mon2000 mon2000 ROM monitor
419 target ppcbug PPCBUG ROM monitor for PowerPC
421 * Support for reading/writing memory and extracting values on architectures
422 whose memory is addressable in units of any integral multiple of 8 bits.
427 Indicates whether the inferior must be started with a shell or not.
430 Indicates that an exec system call was executed.
432 exec-events feature in qSupported
433 The qSupported packet allows GDB to request support for exec
434 events using the new 'gdbfeature' exec-event, and the qSupported
435 response can contain the corresponding 'stubfeature'. Set and
436 show commands can be used to display whether these features are enabled.
439 Equivalent to interrupting with the ^C character, but works in
442 thread created stop reason (T05 create:...)
443 Indicates that the thread was just created and is stopped at entry.
445 thread exit stop reply (w exitcode;tid)
446 Indicates that the thread has terminated.
449 Enables/disables thread create and exit event reporting. For
450 example, this is used in non-stop mode when GDB stops a set of
451 threads and synchronously waits for the their corresponding stop
452 replies. Without exit events, if one of the threads exits, GDB
453 would hang forever not knowing that it should no longer expect a
454 stop for that same thread.
457 Indicates that there are no resumed threads left in the target (all
458 threads are stopped). The remote stub reports support for this stop
459 reply to GDB's qSupported query.
462 Enables/disables catching syscalls from the inferior process.
463 The remote stub reports support for this packet to GDB's qSupported query.
465 syscall_entry stop reason
466 Indicates that a syscall was just called.
468 syscall_return stop reason
469 Indicates that a syscall just returned.
471 * Extended-remote exec events
473 ** GDB now has support for exec events on extended-remote Linux targets.
474 For such targets with Linux kernels 2.5.46 and later, this enables
475 follow-exec-mode and exec catchpoints.
477 set remote exec-event-feature-packet
478 show remote exec-event-feature-packet
479 Set/show the use of the remote exec event feature.
481 * Thread names in remote protocol
483 The reply to qXfer:threads:read may now include a name attribute for each
486 * Target remote mode fork and exec events
488 ** GDB now has support for fork and exec events on target remote mode
489 Linux targets. For such targets with Linux kernels 2.5.46 and later,
490 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
491 fork and exec catchpoints.
493 * Remote syscall events
495 ** GDB now has support for catch syscall on remote Linux targets,
496 currently enabled on x86/x86_64 architectures.
498 set remote catch-syscall-packet
499 show remote catch-syscall-packet
500 Set/show the use of the remote catch syscall feature.
504 ** The -var-set-format command now accepts the zero-hexadecimal
505 format. It outputs data in hexadecimal format with zero-padding on the
510 ** gdb.InferiorThread objects have a new attribute "global_num",
511 which refers to the thread's global thread ID. The existing
512 "num" attribute now refers to the thread's per-inferior number.
513 See "Per-inferior thread numbers" above.
514 ** gdb.InferiorThread objects have a new attribute "inferior", which
515 is the Inferior object the thread belongs to.
517 *** Changes in GDB 7.10
519 * Support for process record-replay and reverse debugging on aarch64*-linux*
520 targets has been added. GDB now supports recording of A64 instruction set
521 including advance SIMD instructions.
523 * Support for Sun's version of the "stabs" debug file format has been removed.
525 * GDB now honors the content of the file /proc/PID/coredump_filter
526 (PID is the process ID) on GNU/Linux systems. This file can be used
527 to specify the types of memory mappings that will be included in a
528 corefile. For more information, please refer to the manual page of
529 "core(5)". GDB also has a new command: "set use-coredump-filter
530 on|off". It allows to set whether GDB will read the content of the
531 /proc/PID/coredump_filter file when generating a corefile.
533 * The "info os" command on GNU/Linux can now display information on
535 "info os cpus" Listing of all cpus/cores on the system
537 * GDB has two new commands: "set serial parity odd|even|none" and
538 "show serial parity". These allows to set or show parity for the
541 * The "info source" command now displays the producer string if it was
542 present in the debug info. This typically includes the compiler version
543 and may include things like its command line arguments.
545 * The "info dll", an alias of the "info sharedlibrary" command,
546 is now available on all platforms.
548 * Directory names supplied to the "set sysroot" commands may be
549 prefixed with "target:" to tell GDB to access shared libraries from
550 the target system, be it local or remote. This replaces the prefix
551 "remote:". The default sysroot has been changed from "" to
552 "target:". "remote:" is automatically converted to "target:" for
553 backward compatibility.
555 * The system root specified by "set sysroot" will be prepended to the
556 filename of the main executable (if reported to GDB as absolute by
557 the operating system) when starting processes remotely, and when
558 attaching to already-running local or remote processes.
560 * GDB now supports automatic location and retrieval of executable
561 files from remote targets. Remote debugging can now be initiated
562 using only a "target remote" or "target extended-remote" command
563 (no "set sysroot" or "file" commands are required). See "New remote
566 * The "dump" command now supports verilog hex format.
568 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
570 * On GNU/Linux, GDB and gdbserver are now able to access executable
571 and shared library files without a "set sysroot" command when
572 attaching to processes running in different mount namespaces from
573 the debugger. This makes it possible to attach to processes in
574 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
575 See "New remote packets" below.
577 * The "tui reg" command now provides completion for all of the
578 available register groups, including target specific groups.
580 * The HISTSIZE environment variable is no longer read when determining
581 the size of GDB's command history. GDB now instead reads the dedicated
582 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
583 disables truncation of command history. Non-numeric values of GDBHISTSIZE
588 ** Memory ports can now be unbuffered.
592 ** gdb.Objfile objects have a new attribute "username",
593 which is the name of the objfile as specified by the user,
594 without, for example, resolving symlinks.
595 ** You can now write frame unwinders in Python.
596 ** gdb.Type objects have a new method "optimized_out",
597 returning optimized out gdb.Value instance of this type.
598 ** gdb.Value objects have new methods "reference_value" and
599 "const_value" which return a reference to the value and a
600 "const" version of the value respectively.
604 maint print symbol-cache
605 Print the contents of the symbol cache.
607 maint print symbol-cache-statistics
608 Print statistics of symbol cache usage.
610 maint flush-symbol-cache
611 Flush the contents of the symbol cache.
615 Start branch trace recording using Branch Trace Store (BTS) format.
618 Evaluate expression by using the compiler and print result.
622 Explicit commands for enabling and disabling tui mode.
625 set mpx bound on i386 and amd64
626 Support for bound table investigation on Intel MPX enabled applications.
630 Start branch trace recording using Intel Processor Trace format.
633 Print information about branch tracing internals.
635 maint btrace packet-history
636 Print the raw branch tracing data.
638 maint btrace clear-packet-history
639 Discard the stored raw branch tracing data.
642 Discard all branch tracing data. It will be fetched and processed
643 anew by the next "record" command.
648 Renamed from "set debug dwarf2-die".
650 Renamed from "show debug dwarf2-die".
653 Renamed from "set debug dwarf2-read".
654 show debug dwarf-read
655 Renamed from "show debug dwarf2-read".
657 maint set dwarf always-disassemble
658 Renamed from "maint set dwarf2 always-disassemble".
659 maint show dwarf always-disassemble
660 Renamed from "maint show dwarf2 always-disassemble".
662 maint set dwarf max-cache-age
663 Renamed from "maint set dwarf2 max-cache-age".
664 maint show dwarf max-cache-age
665 Renamed from "maint show dwarf2 max-cache-age".
668 show debug dwarf-line
669 Control display of debugging info regarding DWARF line processing.
673 Set the maximum number of candidates to be considered during
674 completion. The default value is 200. This limit allows GDB
675 to avoid generating large completion lists, the computation of
676 which can cause the debugger to become temporarily unresponsive.
678 set history remove-duplicates
679 show history remove-duplicates
680 Control the removal of duplicate history entries.
682 maint set symbol-cache-size
683 maint show symbol-cache-size
684 Control the size of the symbol cache.
686 set|show record btrace bts buffer-size
687 Set and show the size of the ring buffer used for branch tracing in
689 The obtained size may differ from the requested size. Use "info
690 record" to see the obtained buffer size.
692 set debug linux-namespaces
693 show debug linux-namespaces
694 Control display of debugging info regarding Linux namespaces.
696 set|show record btrace pt buffer-size
697 Set and show the size of the ring buffer used for branch tracing in
698 Intel Processor Trace format.
699 The obtained size may differ from the requested size. Use "info
700 record" to see the obtained buffer size.
702 maint set|show btrace pt skip-pad
703 Set and show whether PAD packets are skipped when computing the
706 * The command 'thread apply all' can now support new option '-ascending'
707 to call its specified command for all threads in ascending order.
709 * Python/Guile scripting
711 ** GDB now supports auto-loading of Python/Guile scripts contained in the
712 special section named `.debug_gdb_scripts'.
716 qXfer:btrace-conf:read
717 Return the branch trace configuration for the current thread.
719 Qbtrace-conf:bts:size
720 Set the requested ring buffer size for branch tracing in BTS format.
723 Enable Intel Procesor Trace-based branch tracing for the current
724 process. The remote stub reports support for this packet to GDB's
728 Set the requested ring buffer size for branch tracing in Intel Processor
732 Indicates a memory breakpoint instruction was executed, irrespective
733 of whether it was GDB that planted the breakpoint or the breakpoint
734 is hardcoded in the program. This is required for correct non-stop
738 Indicates the target stopped for a hardware breakpoint. This is
739 required for correct non-stop mode operation.
742 Return information about files on the remote system.
745 Return the full absolute name of the file that was executed to
746 create a process running on the remote system.
749 Select the filesystem on which vFile: operations with filename
750 arguments will operate. This is required for GDB to be able to
751 access files on remote targets where the remote stub does not
752 share a common filesystem with the inferior(s).
755 Indicates that a fork system call was executed.
758 Indicates that a vfork system call was executed.
760 vforkdone stop reason
761 Indicates that a vfork child of the specified process has executed
762 an exec or exit, allowing the vfork parent to resume execution.
764 fork-events and vfork-events features in qSupported
765 The qSupported packet allows GDB to request support for fork and
766 vfork events using new 'gdbfeatures' fork-events and vfork-events,
767 and the qSupported response can contain the corresponding
768 'stubfeatures'. Set and show commands can be used to display
769 whether these features are enabled.
771 * Extended-remote fork events
773 ** GDB now has support for fork events on extended-remote Linux
774 targets. For targets with Linux kernels 2.5.60 and later, this
775 enables follow-fork-mode and detach-on-fork for both fork and
776 vfork, as well as fork and vfork catchpoints.
778 * The info record command now shows the recording format and the
779 branch tracing configuration for the current thread when using
780 the btrace record target.
781 For the BTS format, it shows the ring buffer size.
783 * GDB now has support for DTrace USDT (Userland Static Defined
784 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
786 * GDB now supports access to vector registers on S/390 GNU/Linux
789 * Removed command line options
791 -xdb HP-UX XDB compatibility mode.
793 * Removed targets and native configurations
795 HP/PA running HP-UX hppa*-*-hpux*
796 Itanium running HP-UX ia64-*-hpux*
798 * New configure options
801 This configure option allows the user to build GDB with support for
802 Intel Processor Trace (default: auto). This requires libipt.
804 --with-libipt-prefix=PATH
805 Specify the path to the version of libipt that GDB should use.
806 $PATH/include should contain the intel-pt.h header and
807 $PATH/lib should contain the libipt.so library.
809 *** Changes in GDB 7.9.1
813 ** Xmethods can now specify a result type.
815 *** Changes in GDB 7.9
817 * GDB now supports hardware watchpoints on x86 GNU Hurd.
821 ** You can now access frame registers from Python scripts.
822 ** New attribute 'producer' for gdb.Symtab objects.
823 ** gdb.Objfile objects have a new attribute "progspace",
824 which is the gdb.Progspace object of the containing program space.
825 ** gdb.Objfile objects have a new attribute "owner".
826 ** gdb.Objfile objects have a new attribute "build_id",
827 which is the build ID generated when the file was built.
828 ** gdb.Objfile objects have a new method "add_separate_debug_file".
829 ** A new event "gdb.clear_objfiles" has been added, triggered when
830 selecting a new file to debug.
831 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
832 ** New function gdb.lookup_objfile.
834 New events which are triggered when GDB modifies the state of the
837 ** gdb.events.inferior_call_pre: Function call is about to be made.
838 ** gdb.events.inferior_call_post: Function call has just been made.
839 ** gdb.events.memory_changed: A memory location has been altered.
840 ** gdb.events.register_changed: A register has been altered.
842 * New Python-based convenience functions:
844 ** $_caller_is(name [, number_of_frames])
845 ** $_caller_matches(regexp [, number_of_frames])
846 ** $_any_caller_is(name [, number_of_frames])
847 ** $_any_caller_matches(regexp [, number_of_frames])
849 * GDB now supports the compilation and injection of source code into
850 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
851 to compile the source code to object code, and if successful, inject
852 and execute that code within the current context of the inferior.
853 Currently the C language is supported. The commands used to
854 interface with this new feature are:
856 compile code [-raw|-r] [--] [source code]
857 compile file [-raw|-r] filename
861 demangle [-l language] [--] name
862 Demangle "name" in the specified language, or the current language
863 if elided. This command is renamed from the "maint demangle" command.
864 The latter is kept as a no-op to avoid "maint demangle" being interpreted
865 as "maint demangler-warning".
867 queue-signal signal-name-or-number
868 Queue a signal to be delivered to the thread when it is resumed.
870 add-auto-load-scripts-directory directory
871 Add entries to the list of directories from which to load auto-loaded
874 maint print user-registers
875 List all currently available "user" registers.
877 compile code [-r|-raw] [--] [source code]
878 Compile, inject, and execute in the inferior the executable object
879 code produced by compiling the provided source code.
881 compile file [-r|-raw] filename
882 Compile and inject into the inferior the executable object code
883 produced by compiling the source code stored in the filename
886 * On resume, GDB now always passes the signal the program had stopped
887 for to the thread the signal was sent to, even if the user changed
888 threads before resuming. Previously GDB would often (but not
889 always) deliver the signal to the thread that happens to be current
892 * Conversely, the "signal" command now consistently delivers the
893 requested signal to the current thread. GDB now asks for
894 confirmation if the program had stopped for a signal and the user
895 switched threads meanwhile.
897 * "breakpoint always-inserted" modes "off" and "auto" merged.
899 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
900 won't remove breakpoints from the target until all threads stop,
901 even in non-stop mode. The "auto" mode has been removed, and "off"
902 is now the default mode.
906 set debug symbol-lookup
907 show debug symbol-lookup
908 Control display of debugging info regarding symbol lookup.
912 ** The -list-thread-groups command outputs an exit-code field for
913 inferiors that have exited.
917 MIPS SDE mips*-sde*-elf*
921 Support for these obsolete configurations has been removed.
923 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
924 SGI Irix-5.x mips-*-irix5*
925 SGI Irix-6.x mips-*-irix6*
926 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
927 VAX running Ultrix vax-*-ultrix*
929 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
930 and "assf"), have been removed. Use the "sharedlibrary" command, or
931 its alias "share", instead.
933 *** Changes in GDB 7.8
935 * New command line options
938 This is an alias for the --data-directory option.
940 * GDB supports printing and modifying of variable length automatic arrays
941 as specified in ISO C99.
943 * The ARM simulator now supports instruction level tracing
944 with or without disassembly.
948 GDB now has support for scripting using Guile. Whether this is
949 available is determined at configure time.
950 Guile version 2.0 or greater is required.
951 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
953 * New commands (for set/show, see "New options" below)
957 Invoke CODE by passing it to the Guile interpreter.
961 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
963 info auto-load guile-scripts [regexp]
964 Print the list of automatically loaded Guile scripts.
966 * The source command is now capable of sourcing Guile scripts.
967 This feature is dependent on the debugger being built with Guile support.
971 set print symbol-loading (off|brief|full)
972 show print symbol-loading
973 Control whether to print informational messages when loading symbol
974 information for a file. The default is "full", but when debugging
975 programs with large numbers of shared libraries the amount of output
978 set guile print-stack (none|message|full)
979 show guile print-stack
980 Show a stack trace when an error is encountered in a Guile script.
982 set auto-load guile-scripts (on|off)
983 show auto-load guile-scripts
984 Control auto-loading of Guile script files.
986 maint ada set ignore-descriptive-types (on|off)
987 maint ada show ignore-descriptive-types
988 Control whether the debugger should ignore descriptive types in Ada
989 programs. The default is not to ignore the descriptive types. See
990 the user manual for more details on descriptive types and the intended
991 usage of this option.
993 set auto-connect-native-target
995 Control whether GDB is allowed to automatically connect to the
996 native target for the run, attach, etc. commands when not connected
997 to any target yet. See also "target native" below.
999 set record btrace replay-memory-access (read-only|read-write)
1000 show record btrace replay-memory-access
1001 Control what memory accesses are allowed during replay.
1003 maint set target-async (on|off)
1004 maint show target-async
1005 This controls whether GDB targets operate in synchronous or
1006 asynchronous mode. Normally the default is asynchronous, if it is
1007 available; but this can be changed to more easily debug problems
1008 occurring only in synchronous mode.
1010 set mi-async (on|off)
1012 Control whether MI asynchronous mode is preferred. This supersedes
1013 "set target-async" of previous GDB versions.
1015 * "set target-async" is deprecated as a CLI option and is now an alias
1016 for "set mi-async" (only puts MI into async mode).
1018 * Background execution commands (e.g., "c&", "s&", etc.) are now
1019 possible ``out of the box'' if the target supports them. Previously
1020 the user would need to explicitly enable the possibility with the
1021 "set target-async on" command.
1023 * New features in the GDB remote stub, GDBserver
1025 ** New option --debug-format=option1[,option2,...] allows one to add
1026 additional text to each output. At present only timestamps
1027 are supported: --debug-format=timestamps.
1028 Timestamps can also be turned on with the
1029 "monitor set debug-format timestamps" command from GDB.
1031 * The 'record instruction-history' command now starts counting instructions
1032 at one. This also affects the instruction ranges reported by the
1033 'record function-call-history' command when given the /i modifier.
1035 * The command 'record function-call-history' supports a new modifier '/c' to
1036 indent the function names based on their call stack depth.
1037 The fields for the '/i' and '/l' modifier have been reordered.
1038 The source line range is now prefixed with 'at'.
1039 The instruction range is now prefixed with 'inst'.
1040 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1041 "record instruction-history" and "list" commands.
1043 * The ranges given as arguments to the 'record function-call-history' and
1044 'record instruction-history' commands are now inclusive.
1046 * The btrace record target now supports the 'record goto' command.
1047 For locations inside the execution trace, the back trace is computed
1048 based on the information stored in the execution trace.
1050 * The btrace record target supports limited reverse execution and replay.
1051 The target does not record data and therefore does not allow reading
1052 memory or registers.
1054 * The "catch syscall" command now works on s390*-linux* targets.
1056 * The "compare-sections" command is no longer specific to target
1057 remote. It now works with all targets.
1059 * All native targets are now consistently called "native".
1060 Consequently, the "target child", "target GNU", "target djgpp",
1061 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1062 commands have been replaced with "target native". The QNX/NTO port
1063 leaves the "procfs" target in place and adds a "native" target for
1064 consistency with other ports. The impact on users should be minimal
1065 as these commands previously either throwed an error, or were
1066 no-ops. The target's name is visible in the output of the following
1067 commands: "help target", "info target", "info files", "maint print
1070 * The "target native" command now connects to the native target. This
1071 can be used to launch native programs even when "set
1072 auto-connect-native-target" is set to off.
1074 * GDB now supports access to Intel MPX registers on GNU/Linux.
1076 * Support for Intel AVX-512 registers on GNU/Linux.
1077 Support displaying and modifying Intel AVX-512 registers
1078 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1080 * New remote packets
1082 qXfer:btrace:read's annex
1083 The qXfer:btrace:read packet supports a new annex 'delta' to read
1084 branch trace incrementally.
1088 ** Valid Python operations on gdb.Value objects representing
1089 structs/classes invoke the corresponding overloaded operators if
1091 ** New `Xmethods' feature in the Python API. Xmethods are
1092 additional methods or replacements for existing methods of a C++
1093 class. This feature is useful for those cases where a method
1094 defined in C++ source code could be inlined or optimized out by
1095 the compiler, making it unavailable to GDB.
1098 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1100 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1101 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1102 its alias "share", instead.
1104 * The commands "set remotebaud" and "show remotebaud" are no longer
1105 supported. Use "set serial baud" and "show serial baud" (respectively)
1110 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1111 target-async". The latter is left as a deprecated alias of the
1112 former for backward compatibility. If the target supports it,
1113 CLI background execution commands are now always possible by
1114 default, independently of whether the frontend stated a
1115 preference for asynchronous execution with "-gdb-set mi-async".
1116 Previously "-gdb-set target-async off" affected both MI execution
1117 commands and CLI execution commands.
1119 *** Changes in GDB 7.7
1121 * Improved support for process record-replay and reverse debugging on
1122 arm*-linux* targets. Support for thumb32 and syscall instruction
1123 recording has been added.
1125 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1127 * GDB now supports Fission DWP file format version 2.
1128 http://gcc.gnu.org/wiki/DebugFission
1130 * New convenience function "$_isvoid", to check whether an expression
1131 is void. A void expression is an expression where the type of the
1132 result is "void". For example, some convenience variables may be
1133 "void" when evaluated (e.g., "$_exitcode" before the execution of
1134 the program being debugged; or an undefined convenience variable).
1135 Another example, when calling a function whose return type is
1138 * The "maintenance print objfiles" command now takes an optional regexp.
1140 * The "catch syscall" command now works on arm*-linux* targets.
1142 * GDB now consistently shows "<not saved>" when printing values of
1143 registers the debug info indicates have not been saved in the frame
1144 and there's nowhere to retrieve them from
1145 (callee-saved/call-clobbered registers):
1150 (gdb) info registers rax
1153 Before, the former would print "<optimized out>", and the latter
1154 "*value not available*".
1156 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1161 ** Frame filters and frame decorators have been added.
1162 ** Temporary breakpoints are now supported.
1163 ** Line tables representation has been added.
1164 ** New attribute 'parent_type' for gdb.Field objects.
1165 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1166 ** New attribute 'name' for gdb.Type objects.
1170 Nios II ELF nios2*-*-elf
1171 Nios II GNU/Linux nios2*-*-linux
1172 Texas Instruments MSP430 msp430*-*-elf
1174 * Removed native configurations
1176 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1177 been removed. ELF variants of these configurations are kept supported.
1179 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1180 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1181 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1182 i[34567]86-*-openbsd3.[0-3]
1183 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1184 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1185 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1189 Like "catch throw", but catches a re-thrown exception.
1190 maint check-psymtabs
1191 Renamed from old "maint check-symtabs".
1193 Perform consistency checks on symtabs.
1194 maint expand-symtabs
1195 Expand symtabs matching an optional regexp.
1198 Display the details of GDB configure-time options.
1200 maint set|show per-command
1201 maint set|show per-command space
1202 maint set|show per-command time
1203 maint set|show per-command symtab
1204 Enable display of per-command gdb resource usage.
1206 remove-symbol-file FILENAME
1207 remove-symbol-file -a ADDRESS
1208 Remove a symbol file added via add-symbol-file. The file to remove
1209 can be identified by its filename or by an address that lies within
1210 the boundaries of this symbol file in memory.
1213 info exceptions REGEXP
1214 Display the list of Ada exceptions defined in the program being
1215 debugged. If provided, only the exceptions whose names match REGEXP
1220 set debug symfile off|on
1222 Control display of debugging info regarding reading symbol files and
1223 symbol tables within those files
1225 set print raw frame-arguments
1226 show print raw frame-arguments
1227 Set/show whether to print frame arguments in raw mode,
1228 disregarding any defined pretty-printers.
1230 set remote trace-status-packet
1231 show remote trace-status-packet
1232 Set/show the use of remote protocol qTStatus packet.
1236 Control display of debugging messages related to Nios II targets.
1240 Control whether target-assisted range stepping is enabled.
1242 set startup-with-shell
1243 show startup-with-shell
1244 Specifies whether Unix child processes are started via a shell or
1249 Use the target memory cache for accesses to the code segment. This
1250 improves performance of remote debugging (particularly disassembly).
1252 * You can now use a literal value 'unlimited' for options that
1253 interpret 0 or -1 as meaning "unlimited". E.g., "set
1254 trace-buffer-size unlimited" is now an alias for "set
1255 trace-buffer-size -1" and "set height unlimited" is now an alias for
1258 * The "set debug symtab-create" debugging option of GDB has been changed to
1259 accept a verbosity level. 0 means "off", 1 provides basic debugging
1260 output, and values of 2 or greater provides more verbose output.
1262 * New command-line options
1264 Display the details of GDB configure-time options.
1266 * The command 'tsave' can now support new option '-ctf' to save trace
1267 buffer in Common Trace Format.
1269 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1272 * GDB now implements the the C++ 'typeid' operator.
1274 * The new convenience variable $_exception holds the exception being
1275 thrown or caught at an exception-related catchpoint.
1277 * The exception-related catchpoints, like "catch throw", now accept a
1278 regular expression which can be used to filter exceptions by type.
1280 * The new convenience variable $_exitsignal is automatically set to
1281 the terminating signal number when the program being debugged dies
1282 due to an uncaught signal.
1286 ** All MI commands now accept an optional "--language" option.
1287 Support for this feature can be verified by using the "-list-features"
1288 command, which should contain "language-option".
1290 ** The new command -info-gdb-mi-command allows the user to determine
1291 whether a GDB/MI command is supported or not.
1293 ** The "^error" result record returned when trying to execute an undefined
1294 GDB/MI command now provides a variable named "code" whose content is the
1295 "undefined-command" error code. Support for this feature can be verified
1296 by using the "-list-features" command, which should contain
1297 "undefined-command-error-code".
1299 ** The -trace-save MI command can optionally save trace buffer in Common
1302 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1304 ** The command -data-list-register-values now accepts an optional
1305 "--skip-unavailable" option. When used, only the available registers
1308 ** The new command -trace-frame-collected dumps collected variables,
1309 computed expressions, tvars, memory and registers in a traceframe.
1311 ** The commands -stack-list-locals, -stack-list-arguments and
1312 -stack-list-variables now accept an option "--skip-unavailable".
1313 When used, only the available locals or arguments are displayed.
1315 ** The -exec-run command now accepts an optional "--start" option.
1316 When used, the command follows the same semantics as the "start"
1317 command, stopping the program's execution at the start of its
1318 main subprogram. Support for this feature can be verified using
1319 the "-list-features" command, which should contain
1320 "exec-run-start-option".
1322 ** The new commands -catch-assert and -catch-exceptions insert
1323 catchpoints stopping the program when Ada exceptions are raised.
1325 ** The new command -info-ada-exceptions provides the equivalent of
1326 the new "info exceptions" command.
1328 * New system-wide configuration scripts
1329 A GDB installation now provides scripts suitable for use as system-wide
1330 configuration scripts for the following systems:
1334 * GDB now supports target-assigned range stepping with remote targets.
1335 This improves the performance of stepping source lines by reducing
1336 the number of control packets from/to GDB. See "New remote packets"
1339 * GDB now understands the element 'tvar' in the XML traceframe info.
1340 It has the id of the collected trace state variables.
1342 * On S/390 targets that provide the transactional-execution feature,
1343 the program interruption transaction diagnostic block (TDB) is now
1344 represented as a number of additional "registers" in GDB.
1346 * New remote packets
1350 The vCont packet supports a new 'r' action, that tells the remote
1351 stub to step through an address range itself, without GDB
1352 involvemement at each single-step.
1354 qXfer:libraries-svr4:read's annex
1355 The previously unused annex of the qXfer:libraries-svr4:read packet
1356 is now used to support passing an argument list. The remote stub
1357 reports support for this argument list to GDB's qSupported query.
1358 The defined arguments are "start" and "prev", used to reduce work
1359 necessary for library list updating, resulting in significant
1362 * New features in the GDB remote stub, GDBserver
1364 ** GDBserver now supports target-assisted range stepping. Currently
1365 enabled on x86/x86_64 GNU/Linux targets.
1367 ** GDBserver now adds element 'tvar' in the XML in the reply to
1368 'qXfer:traceframe-info:read'. It has the id of the collected
1369 trace state variables.
1371 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1374 * New 'z' formatter for printing and examining memory, this displays the
1375 value as hexadecimal zero padded on the left to the size of the type.
1377 * GDB can now use Windows x64 unwinding data.
1379 * The "set remotebaud" command has been replaced by "set serial baud".
1380 Similarly, "show remotebaud" has been replaced by "show serial baud".
1381 The "set remotebaud" and "show remotebaud" commands are still available
1382 to provide backward compatibility with older versions of GDB.
1384 *** Changes in GDB 7.6
1386 * Target record has been renamed to record-full.
1387 Record/replay is now enabled with the "record full" command.
1388 This also affects settings that are associated with full record/replay
1389 that have been moved from "set/show record" to "set/show record full":
1391 set|show record full insn-number-max
1392 set|show record full stop-at-limit
1393 set|show record full memory-query
1395 * A new record target "record-btrace" has been added. The new target
1396 uses hardware support to record the control-flow of a process. It
1397 does not support replaying the execution, but it implements the
1398 below new commands for investigating the recorded execution log.
1399 This new recording method can be enabled using:
1403 The "record-btrace" target is only available on Intel Atom processors
1404 and requires a Linux kernel 2.6.32 or later.
1406 * Two new commands have been added for record/replay to give information
1407 about the recorded execution without having to replay the execution.
1408 The commands are only supported by "record btrace".
1410 record instruction-history prints the execution history at
1411 instruction granularity
1413 record function-call-history prints the execution history at
1414 function granularity
1416 * New native configurations
1418 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1419 FreeBSD/powerpc powerpc*-*-freebsd
1420 x86_64/Cygwin x86_64-*-cygwin*
1421 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1425 ARM AArch64 aarch64*-*-elf
1426 ARM AArch64 GNU/Linux aarch64*-*-linux
1427 Lynx 178 PowerPC powerpc-*-lynx*178
1428 x86_64/Cygwin x86_64-*-cygwin*
1429 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1431 * If the configured location of system.gdbinit file (as given by the
1432 --with-system-gdbinit option at configure time) is in the
1433 data-directory (as specified by --with-gdb-datadir at configure
1434 time) or in one of its subdirectories, then GDB will look for the
1435 system-wide init file in the directory specified by the
1436 --data-directory command-line option.
1438 * New command line options:
1440 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1441 other initialization files, unlike -nx which disables all of them.
1443 * Removed command line options
1445 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1448 * The 'ptype' and 'whatis' commands now accept an argument to control
1451 * 'info proc' now works on some core files.
1455 ** Vectors can be created with gdb.Type.vector.
1457 ** Python's atexit.register now works in GDB.
1459 ** Types can be pretty-printed via a Python API.
1461 ** Python 3 is now supported (in addition to Python 2.4 or later)
1463 ** New class gdb.Architecture exposes GDB's internal representation
1464 of architecture in the Python API.
1466 ** New method Frame.architecture returns the gdb.Architecture object
1467 corresponding to the frame's architecture.
1469 * New Python-based convenience functions:
1471 ** $_memeq(buf1, buf2, length)
1472 ** $_streq(str1, str2)
1474 ** $_regex(str, regex)
1476 * The 'cd' command now defaults to using '~' (the home directory) if not
1479 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1480 default for GCC since November 2000.
1482 * The command 'forward-search' can now be abbreviated as 'fo'.
1484 * The command 'info tracepoints' can now display 'installed on target'
1485 or 'not installed on target' for each non-pending location of tracepoint.
1487 * New configure options
1489 --enable-libmcheck/--disable-libmcheck
1490 By default, development versions are built with -lmcheck on hosts
1491 that support it, in order to help track memory corruption issues.
1492 Release versions, on the other hand, are built without -lmcheck
1493 by default. The --enable-libmcheck/--disable-libmcheck configure
1494 options allow the user to override that default.
1495 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1496 This configure option allows the user to build GDB with
1497 libbabeltrace using which GDB can read Common Trace Format data.
1499 * New commands (for set/show, see "New options" below)
1502 Catch signals. This is similar to "handle", but allows commands and
1503 conditions to be attached.
1506 List the BFDs known to GDB.
1508 python-interactive [command]
1510 Start a Python interactive prompt, or evaluate the optional command
1511 and print the result of expressions.
1514 "py" is a new alias for "python".
1516 enable type-printer [name]...
1517 disable type-printer [name]...
1518 Enable or disable type printers.
1522 ** For the Renesas Super-H architecture, the "regs" command has been removed
1523 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1528 set print type methods (on|off)
1529 show print type methods
1530 Control whether method declarations are displayed by "ptype".
1531 The default is to show them.
1533 set print type typedefs (on|off)
1534 show print type typedefs
1535 Control whether typedef definitions are displayed by "ptype".
1536 The default is to show them.
1538 set filename-display basename|relative|absolute
1539 show filename-display
1540 Control the way in which filenames is displayed.
1541 The default is "relative", which preserves previous behavior.
1543 set trace-buffer-size
1544 show trace-buffer-size
1545 Request target to change the size of trace buffer.
1547 set remote trace-buffer-size-packet auto|on|off
1548 show remote trace-buffer-size-packet
1549 Control the use of the remote protocol `QTBuffer:size' packet.
1553 Control display of debugging messages related to ARM AArch64.
1556 set debug coff-pe-read
1557 show debug coff-pe-read
1558 Control display of debugging messages related to reading of COFF/PE
1563 Control display of debugging messages related to Mach-O symbols
1566 set debug notification
1567 show debug notification
1568 Control display of debugging info for async remote notification.
1572 ** Command parameter changes are now notified using new async record
1573 "=cmd-param-changed".
1574 ** Trace frame changes caused by command "tfind" are now notified using
1575 new async record "=traceframe-changed".
1576 ** The creation, deletion and modification of trace state variables
1577 are now notified using new async records "=tsv-created",
1578 "=tsv-deleted" and "=tsv-modified".
1579 ** The start and stop of process record are now notified using new
1580 async record "=record-started" and "=record-stopped".
1581 ** Memory changes are now notified using new async record
1583 ** The data-disassemble command response will include a "fullname" field
1584 containing the absolute file name when source has been requested.
1585 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1586 command, to allow pattern filling of memory areas.
1587 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1588 library load/unload events.
1589 ** The response to breakpoint commands and breakpoint async records
1590 includes an "installed" field containing a boolean state about each
1591 non-pending tracepoint location is whether installed on target or not.
1592 ** Output of the "-trace-status" command includes a "trace-file" field
1593 containing the name of the trace file being examined. This field is
1594 optional, and only present when examining a trace file.
1595 ** The "fullname" field is now always present along with the "file" field,
1596 even if the file cannot be found by GDB.
1598 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1599 You must have the LZMA library available when configuring GDB for this
1600 feature to be enabled. For more information, see:
1601 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1603 * New remote packets
1606 Set the size of trace buffer. The remote stub reports support for this
1607 packet to gdb's qSupported query.
1610 Enable Branch Trace Store (BTS)-based branch tracing for the current
1611 thread. The remote stub reports support for this packet to gdb's
1615 Disable branch tracing for the current thread. The remote stub reports
1616 support for this packet to gdb's qSupported query.
1619 Read the traced branches for the current thread. The remote stub
1620 reports support for this packet to gdb's qSupported query.
1622 *** Changes in GDB 7.5
1624 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1625 for more x32 ABI info.
1627 * GDB now supports access to MIPS DSP registers on Linux targets.
1629 * GDB now supports debugging microMIPS binaries.
1631 * The "info os" command on GNU/Linux can now display information on
1632 several new classes of objects managed by the operating system:
1633 "info os procgroups" lists process groups
1634 "info os files" lists file descriptors
1635 "info os sockets" lists internet-domain sockets
1636 "info os shm" lists shared-memory regions
1637 "info os semaphores" lists semaphores
1638 "info os msg" lists message queues
1639 "info os modules" lists loaded kernel modules
1641 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1642 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1643 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1644 options and inspect the probe arguments using the new $_probe_arg family
1645 of convenience variables. You can obtain more information about SystemTap
1646 in <http://sourceware.org/systemtap/>.
1648 * GDB now supports reversible debugging on ARM, it allows you to
1649 debug basic ARM and THUMB instructions, and provides
1650 record/replay support.
1652 * The option "symbol-reloading" has been deleted as it is no longer used.
1656 ** GDB commands implemented in Python can now be put in command class
1659 ** The "maint set python print-stack on|off" is now deleted.
1661 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1662 apply "flag enum"-style pretty-printing to any enum.
1664 ** gdb.lookup_symbol can now work when there is no current frame.
1666 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1667 the source at which the symbol was defined.
1669 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1670 method 'value'. The former indicates whether the symbol needs a
1671 frame in order to compute its value, and the latter computes the
1674 ** A new method 'referenced_value' on gdb.Value objects which can
1675 dereference pointer as well as C++ reference values.
1677 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1678 which return the global and static blocks (as gdb.Block objects),
1679 of the underlying symbol table, respectively.
1681 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1682 object associated with a PC value.
1684 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1685 of the address range occupied by code for the current source line.
1687 * Go language support.
1688 GDB now supports debugging programs written in the Go programming
1691 * GDBserver now supports stdio connections.
1692 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1694 * The binary "gdbtui" can no longer be built or installed.
1695 Use "gdb -tui" instead.
1697 * GDB will now print "flag" enums specially. A flag enum is one where
1698 all the enumerator values have no bits in common when pairwise
1699 "and"ed. When printing a value whose type is a flag enum, GDB will
1700 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1701 (gdb) print (enum E) 3
1704 * The filename part of a linespec will now match trailing components
1705 of a source file name. For example, "break gcc/expr.c:1000" will
1706 now set a breakpoint in build/gcc/expr.c, but not
1707 build/libcpp/expr.c.
1709 * The "info proc" and "generate-core-file" commands will now also
1710 work on remote targets connected to GDBserver on Linux.
1712 * The command "info catch" has been removed. It has been disabled
1713 since December 2007.
1715 * The "catch exception" and "catch assert" commands now accept
1716 a condition at the end of the command, much like the "break"
1717 command does. For instance:
1719 (gdb) catch exception Constraint_Error if Barrier = True
1721 Previously, it was possible to add a condition to such catchpoints,
1722 but it had to be done as a second step, after the catchpoint had been
1723 created, using the "condition" command.
1725 * The "info static-tracepoint-marker" command will now also work on
1726 native Linux targets with in-process agent.
1728 * GDB can now set breakpoints on inlined functions.
1730 * The .gdb_index section has been updated to include symbols for
1731 inlined functions. GDB will ignore older .gdb_index sections by
1732 default, which could cause symbol files to be loaded more slowly
1733 until their .gdb_index sections can be recreated. The new command
1734 "set use-deprecated-index-sections on" will cause GDB to use any older
1735 .gdb_index sections it finds. This will restore performance, but the
1736 ability to set breakpoints on inlined functions will be lost in symbol
1737 files with older .gdb_index sections.
1739 The .gdb_index section has also been updated to record more information
1740 about each symbol. This speeds up the "info variables", "info functions"
1741 and "info types" commands when used with programs having the .gdb_index
1742 section, as well as speeding up debugging with shared libraries using
1743 the .gdb_index section.
1745 * Ada support for GDB/MI Variable Objects has been added.
1747 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1752 ** New command -info-os is the MI equivalent of "info os".
1754 ** Output logs ("set logging" and related) now include MI output.
1758 ** "set use-deprecated-index-sections on|off"
1759 "show use-deprecated-index-sections on|off"
1760 Controls the use of deprecated .gdb_index sections.
1762 ** "catch load" and "catch unload" can be used to stop when a shared
1763 library is loaded or unloaded, respectively.
1765 ** "enable count" can be used to auto-disable a breakpoint after
1768 ** "info vtbl" can be used to show the virtual method tables for
1769 C++ and Java objects.
1771 ** "explore" and its sub commands "explore value" and "explore type"
1772 can be used to recursively explore values and types of
1773 expressions. These commands are available only if GDB is
1774 configured with '--with-python'.
1776 ** "info auto-load" shows status of all kinds of auto-loaded files,
1777 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1778 sequences of commands files, "info auto-load python-scripts"
1779 shows status of auto-loading Python script files,
1780 "info auto-load local-gdbinit" shows status of loading init file
1781 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1782 status of inferior specific thread debugging shared library loading.
1784 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1785 and "show auto-load-scripts" commands have been deprecated, use their
1786 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1787 and "show auto-load python-scripts" counterparts instead.
1789 ** "dprintf location,format,args..." creates a dynamic printf, which
1790 is basically a breakpoint that does a printf and immediately
1791 resumes your program's execution, so it is like a printf that you
1792 can insert dynamically at runtime instead of at compiletime.
1794 ** "set print symbol"
1796 Controls whether GDB attempts to display the symbol, if any,
1797 corresponding to addresses it prints. This defaults to "on", but
1798 you can set it to "off" to restore GDB's previous behavior.
1800 * Deprecated commands
1802 ** For the Renesas Super-H architecture, the "regs" command has been
1803 deprecated, and "info all-registers" should be used instead.
1807 Renesas RL78 rl78-*-elf
1808 HP OpenVMS ia64 ia64-hp-openvms*
1810 * GDBserver supports evaluation of breakpoint conditions. When
1811 support is advertised by GDBserver, GDB may be told to send the
1812 breakpoint conditions in bytecode form to GDBserver. GDBserver
1813 will only report the breakpoint trigger to GDB when its condition
1818 set mips compression
1819 show mips compression
1820 Select the compressed ISA encoding used in functions that have no symbol
1821 information available. The encoding can be set to either of:
1824 and is updated automatically from ELF file flags if available.
1826 set breakpoint condition-evaluation
1827 show breakpoint condition-evaluation
1828 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1829 GDBserver ("target"). Default option "auto" chooses the most efficient
1831 This option can improve debugger efficiency depending on the speed of the
1835 Disable auto-loading globally.
1838 Show auto-loading setting of all kinds of auto-loaded files.
1840 set auto-load gdb-scripts on|off
1841 show auto-load gdb-scripts
1842 Control auto-loading of GDB canned sequences of commands files.
1844 set auto-load python-scripts on|off
1845 show auto-load python-scripts
1846 Control auto-loading of Python script files.
1848 set auto-load local-gdbinit on|off
1849 show auto-load local-gdbinit
1850 Control loading of init file (.gdbinit) from current directory.
1852 set auto-load libthread-db on|off
1853 show auto-load libthread-db
1854 Control auto-loading of inferior specific thread debugging shared library.
1856 set auto-load scripts-directory <dir1>[:<dir2>...]
1857 show auto-load scripts-directory
1858 Set a list of directories from which to load auto-loaded scripts.
1859 Automatically loaded Python scripts and GDB scripts are located in one
1860 of the directories listed by this option.
1861 The delimiter (':' above) may differ according to the host platform.
1863 set auto-load safe-path <dir1>[:<dir2>...]
1864 show auto-load safe-path
1865 Set a list of directories from which it is safe to auto-load files.
1866 The delimiter (':' above) may differ according to the host platform.
1868 set debug auto-load on|off
1869 show debug auto-load
1870 Control display of debugging info for auto-loading the files above.
1872 set dprintf-style gdb|call|agent
1874 Control the way in which a dynamic printf is performed; "gdb"
1875 requests a GDB printf command, while "call" causes dprintf to call a
1876 function in the inferior. "agent" requests that the target agent
1877 (such as GDBserver) do the printing.
1879 set dprintf-function <expr>
1880 show dprintf-function
1881 set dprintf-channel <expr>
1882 show dprintf-channel
1883 Set the function and optional first argument to the call when using
1884 the "call" style of dynamic printf.
1886 set disconnected-dprintf on|off
1887 show disconnected-dprintf
1888 Control whether agent-style dynamic printfs continue to be in effect
1889 after GDB disconnects.
1891 * New configure options
1893 --with-auto-load-dir
1894 Configure default value for the 'set auto-load scripts-directory'
1895 setting above. It defaults to '$debugdir:$datadir/auto-load',
1896 $debugdir representing global debugging info directories (available
1897 via 'show debug-file-directory') and $datadir representing GDB's data
1898 directory (available via 'show data-directory').
1900 --with-auto-load-safe-path
1901 Configure default value for the 'set auto-load safe-path' setting
1902 above. It defaults to the --with-auto-load-dir setting.
1904 --without-auto-load-safe-path
1905 Set 'set auto-load safe-path' to '/', effectively disabling this
1908 * New remote packets
1910 z0/z1 conditional breakpoints extension
1912 The z0/z1 breakpoint insertion packets have been extended to carry
1913 a list of conditional expressions over to the remote stub depending on the
1914 condition evaluation mode. The use of this extension can be controlled
1915 via the "set remote conditional-breakpoints-packet" command.
1919 Specify the signals which the remote stub may pass to the debugged
1920 program without GDB involvement.
1922 * New command line options
1924 --init-command=FILE, -ix Like --command, -x but execute it
1925 before loading inferior.
1926 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1927 execute it before loading inferior.
1929 *** Changes in GDB 7.4
1931 * GDB now handles ambiguous linespecs more consistently; the existing
1932 FILE:LINE support has been expanded to other types of linespecs. A
1933 breakpoint will now be set on all matching locations in all
1934 inferiors, and locations will be added or removed according to
1937 * GDB now allows you to skip uninteresting functions and files when
1938 stepping with the "skip function" and "skip file" commands.
1940 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1941 and "show remote hardware-watchpoint-length-limit". These allows to
1942 set or show the maximum length limit (in bytes) of a remote
1943 target hardware watchpoint.
1945 This allows e.g. to use "unlimited" hardware watchpoints with the
1946 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1947 watchpoints are slower than real hardware watchpoints but are
1948 significantly faster than gdb software watchpoints.
1952 ** The register_pretty_printer function in module gdb.printing now takes
1953 an optional `replace' argument. If True, the new printer replaces any
1956 ** The "maint set python print-stack on|off" command has been
1957 deprecated and will be deleted in GDB 7.5.
1958 A new command: "set python print-stack none|full|message" has
1959 replaced it. Additionally, the default for "print-stack" is
1960 now "message", which just prints the error message without
1963 ** A prompt substitution hook (prompt_hook) is now available to the
1966 ** A new Python module, gdb.prompt has been added to the GDB Python
1967 modules library. This module provides functionality for
1968 escape sequences in prompts (used by set/show
1969 extended-prompt). These escape sequences are replaced by their
1970 corresponding value.
1972 ** Python commands and convenience-functions located in
1973 'data-directory'/python/gdb/command and
1974 'data-directory'/python/gdb/function are now automatically loaded
1977 ** Blocks now provide four new attributes. global_block and
1978 static_block will return the global and static blocks
1979 respectively. is_static and is_global are boolean attributes
1980 that indicate if the block is one of those two types.
1982 ** Symbols now provide the "type" attribute, the type of the symbol.
1984 ** The "gdb.breakpoint" function has been deprecated in favor of
1987 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1988 of a function. This class is based on the "finish" command
1989 available in the CLI.
1991 ** Type objects for struct and union types now allow access to
1992 the fields using standard Python dictionary (mapping) methods.
1993 For example, "some_type['myfield']" now works, as does
1994 "some_type.items()".
1996 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1999 ** A new function, "deep_items" has been added to the gdb.types
2000 module in the GDB Python modules library. This function returns
2001 an iterator over the fields of a struct or union type. Unlike
2002 the standard Python "iteritems" method, it will recursively traverse
2003 any anonymous fields.
2007 ** "*stopped" events can report several new "reason"s, such as
2010 ** Breakpoint changes are now notified using new async records, like
2011 "=breakpoint-modified".
2013 ** New command -ada-task-info.
2015 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2016 $sdir specifies the default system locations of shared libraries.
2017 $pdir specifies the directory where the libpthread used by the application
2020 GDB no longer looks in $sdir and $pdir after it has searched the directories
2021 mentioned in libthread-db-search-path. If you want to search those
2022 directories, they must be specified in libthread-db-search-path.
2023 The default value of libthread-db-search-path on GNU/Linux and Solaris
2024 systems is now "$sdir:$pdir".
2026 $pdir is not supported by gdbserver, it is currently ignored.
2027 $sdir is supported by gdbserver.
2029 * New configure option --with-iconv-bin.
2030 When using the internationalization support like the one in the GNU C
2031 library, GDB will invoke the "iconv" program to get a list of supported
2032 character sets. If this program lives in a non-standard location, one can
2033 use this option to specify where to find it.
2035 * When natively debugging programs on PowerPC BookE processors running
2036 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2037 watchpoints, which specify a mask in addition to an address to watch.
2038 The mask specifies that some bits of an address (the bits which are
2039 reset in the mask) should be ignored when matching the address accessed
2040 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2041 section in the user manual for more details.
2043 * The new option --once causes GDBserver to stop listening for connections once
2044 the first connection is made. The listening port used by GDBserver will
2045 become available after that.
2047 * New commands "info macros" and "alias" have been added.
2049 * New function parameters suffix @entry specifies value of function parameter
2050 at the time the function got called. Entry values are available only since
2056 "!" is now an alias of the "shell" command.
2057 Note that no space is needed between "!" and SHELL COMMAND.
2061 watch EXPRESSION mask MASK_VALUE
2062 The watch command now supports the mask argument which allows creation
2063 of masked watchpoints, if the current architecture supports this feature.
2065 info auto-load-scripts [REGEXP]
2066 This command was formerly named "maintenance print section-scripts".
2067 It is now generally useful and is no longer a maintenance-only command.
2069 info macro [-all] [--] MACRO
2070 The info macro command has new options `-all' and `--'. The first for
2071 printing all definitions of a macro. The second for explicitly specifying
2072 the end of arguments and the beginning of the macro name in case the macro
2073 name starts with a hyphen.
2075 collect[/s] EXPRESSIONS
2076 The tracepoint collect command now takes an optional modifier "/s"
2077 that directs it to dereference pointer-to-character types and
2078 collect the bytes of memory up to a zero byte. The behavior is
2079 similar to what you see when you use the regular print command on a
2080 string. An optional integer following the "/s" sets a bound on the
2081 number of bytes that will be collected.
2084 The trace start command now interprets any supplied arguments as a
2085 note to be recorded with the trace run, with an effect similar to
2086 setting the variable trace-notes.
2089 The trace stop command now interprets any arguments as a note to be
2090 mentioned along with the tstatus report that the trace was stopped
2091 with a command. The effect is similar to setting the variable
2094 * Tracepoints can now be enabled and disabled at any time after a trace
2095 experiment has been started using the standard "enable" and "disable"
2096 commands. It is now possible to start a trace experiment with no enabled
2097 tracepoints; GDB will display a warning, but will allow the experiment to
2098 begin, assuming that tracepoints will be enabled as needed while the trace
2101 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2102 locations with 4-byte instructions, when they were previously
2103 limited to locations with instructions of 5 bytes or longer.
2107 set debug dwarf2-read
2108 show debug dwarf2-read
2109 Turns on or off display of debugging messages related to reading
2110 DWARF debug info. The default is off.
2112 set debug symtab-create
2113 show debug symtab-create
2114 Turns on or off display of debugging messages related to symbol table
2115 creation. The default is off.
2118 show extended-prompt
2119 Set the GDB prompt, and allow escape sequences to be inserted to
2120 display miscellaneous information (see 'help set extended-prompt'
2121 for the list of sequences). This prompt (and any information
2122 accessed through the escape sequences) is updated every time the
2123 prompt is displayed.
2125 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2126 show print entry-values
2127 Set printing of frame argument values at function entry. In some cases
2128 GDB can determine the value of function argument which was passed by the
2129 function caller, even if the value was modified inside the called function.
2131 set debug entry-values
2132 show debug entry-values
2133 Control display of debugging info for determining frame argument values at
2134 function entry and virtual tail call frames.
2136 set basenames-may-differ
2137 show basenames-may-differ
2138 Set whether a source file may have multiple base names.
2139 (A "base name" is the name of a file with the directory part removed.
2140 Example: The base name of "/home/user/hello.c" is "hello.c".)
2141 If set, GDB will canonicalize file names (e.g., expand symlinks)
2142 before comparing them. Canonicalization is an expensive operation,
2143 but it allows the same file be known by more than one base name.
2144 If not set (the default), all source files are assumed to have just
2145 one base name, and gdb will do file name comparisons more efficiently.
2151 Set a user name and notes for the current and any future trace runs.
2152 This is useful for long-running and/or disconnected traces, to
2153 inform others (or yourself) as to who is running the trace, supply
2154 contact information, or otherwise explain what is going on.
2156 set trace-stop-notes
2157 show trace-stop-notes
2158 Set a note attached to the trace run, that is displayed when the
2159 trace has been stopped by a tstop command. This is useful for
2160 instance as an explanation, if you are stopping a trace run that was
2161 started by someone else.
2163 * New remote packets
2167 Dynamically enable a tracepoint in a started trace experiment.
2171 Dynamically disable a tracepoint in a started trace experiment.
2175 Set the user and notes of the trace run.
2179 Query the current status of a tracepoint.
2183 Query the minimum length of instruction at which a fast tracepoint may
2186 * Dcache size (number of lines) and line-size are now runtime-configurable
2187 via "set dcache line" and "set dcache line-size" commands.
2191 Texas Instruments TMS320C6x tic6x-*-*
2195 Renesas RL78 rl78-*-elf
2197 *** Changes in GDB 7.3.1
2199 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2201 *** Changes in GDB 7.3
2203 * GDB has a new command: "thread find [REGEXP]".
2204 It finds the thread id whose name, target id, or thread extra info
2205 matches the given regular expression.
2207 * The "catch syscall" command now works on mips*-linux* targets.
2209 * The -data-disassemble MI command now supports modes 2 and 3 for
2210 dumping the instruction opcodes.
2212 * New command line options
2214 -data-directory DIR Specify DIR as the "data-directory".
2215 This is mostly for testing purposes.
2217 * The "maint set python auto-load on|off" command has been renamed to
2218 "set auto-load-scripts on|off".
2220 * GDB has a new command: "set directories".
2221 It is like the "dir" command except that it replaces the
2222 source path list instead of augmenting it.
2224 * GDB now understands thread names.
2226 On GNU/Linux, "info threads" will display the thread name as set by
2227 prctl or pthread_setname_np.
2229 There is also a new command, "thread name", which can be used to
2230 assign a name internally for GDB to display.
2233 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2234 has been integrated into GDB.
2238 ** The function gdb.Write now accepts an optional keyword 'stream'.
2239 This keyword, when provided, will direct the output to either
2240 stdout, stderr, or GDB's logging output.
2242 ** Parameters can now be be sub-classed in Python, and in particular
2243 you may implement the get_set_doc and get_show_doc functions.
2244 This improves how Parameter set/show documentation is processed
2245 and allows for more dynamic content.
2247 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2248 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2249 have an is_valid method.
2251 ** Breakpoints can now be sub-classed in Python, and in particular
2252 you may implement a 'stop' function that is executed each time
2253 the inferior reaches that breakpoint.
2255 ** New function gdb.lookup_global_symbol looks up a global symbol.
2257 ** GDB values in Python are now callable if the value represents a
2258 function. For example, if 'some_value' represents a function that
2259 takes two integer parameters and returns a value, you can call
2260 that function like so:
2262 result = some_value (10,20)
2264 ** Module gdb.types has been added.
2265 It contains a collection of utilities for working with gdb.Types objects:
2266 get_basic_type, has_field, make_enum_dict.
2268 ** Module gdb.printing has been added.
2269 It contains utilities for writing and registering pretty-printers.
2270 New classes: PrettyPrinter, SubPrettyPrinter,
2271 RegexpCollectionPrettyPrinter.
2272 New function: register_pretty_printer.
2274 ** New commands "info pretty-printers", "enable pretty-printer" and
2275 "disable pretty-printer" have been added.
2277 ** gdb.parameter("directories") is now available.
2279 ** New function gdb.newest_frame returns the newest frame in the
2282 ** The gdb.InferiorThread class has a new "name" attribute. This
2283 holds the thread's name.
2285 ** Python Support for Inferior events.
2286 Python scripts can add observers to be notified of events
2287 occurring in the process being debugged.
2288 The following events are currently supported:
2289 - gdb.events.cont Continue event.
2290 - gdb.events.exited Inferior exited event.
2291 - gdb.events.stop Signal received, and Breakpoint hit events.
2295 ** GDB now puts template parameters in scope when debugging in an
2296 instantiation. For example, if you have:
2298 template<int X> int func (void) { return X; }
2300 then if you step into func<5>, "print X" will show "5". This
2301 feature requires proper debuginfo support from the compiler; it
2302 was added to GCC 4.5.
2304 ** The motion commands "next", "finish", "until", and "advance" now
2305 work better when exceptions are thrown. In particular, GDB will
2306 no longer lose control of the inferior; instead, the GDB will
2307 stop the inferior at the point at which the exception is caught.
2308 This functionality requires a change in the exception handling
2309 code that was introduced in GCC 4.5.
2311 * GDB now follows GCC's rules on accessing volatile objects when
2312 reading or writing target state during expression evaluation.
2313 One notable difference to prior behavior is that "print x = 0"
2314 no longer generates a read of x; the value of the assignment is
2315 now always taken directly from the value being assigned.
2317 * GDB now has some support for using labels in the program's source in
2318 linespecs. For instance, you can use "advance label" to continue
2319 execution to a label.
2321 * GDB now has support for reading and writing a new .gdb_index
2322 section. This section holds a fast index of DWARF debugging
2323 information and can be used to greatly speed up GDB startup and
2324 operation. See the documentation for `save gdb-index' for details.
2326 * The "watch" command now accepts an optional "-location" argument.
2327 When used, this causes GDB to watch the memory referred to by the
2328 expression. Such a watchpoint is never deleted due to it going out
2331 * GDB now supports thread debugging of core dumps on GNU/Linux.
2333 GDB now activates thread debugging using the libthread_db library
2334 when debugging GNU/Linux core dumps, similarly to when debugging
2335 live processes. As a result, when debugging a core dump file, GDB
2336 is now able to display pthread_t ids of threads. For example, "info
2337 threads" shows the same output as when debugging the process when it
2338 was live. In earlier releases, you'd see something like this:
2341 * 1 LWP 6780 main () at main.c:10
2343 While now you see this:
2346 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2348 It is also now possible to inspect TLS variables when debugging core
2351 When debugging a core dump generated on a machine other than the one
2352 used to run GDB, you may need to point GDB at the correct
2353 libthread_db library with the "set libthread-db-search-path"
2354 command. See the user manual for more details on this command.
2356 * When natively debugging programs on PowerPC BookE processors running
2357 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2358 which stop execution of the inferior whenever it executes an instruction
2359 at any address within the specified range. See the "PowerPC Embedded"
2360 section in the user manual for more details.
2362 * New features in the GDB remote stub, GDBserver
2364 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2365 and i686 LynxOS (version 5.x).
2367 ** GDBserver is now supported on Blackfin Linux.
2369 * New native configurations
2371 ia64 HP-UX ia64-*-hpux*
2375 Analog Devices, Inc. Blackfin Processor bfin-*
2377 * Ada task switching is now supported on sparc-elf targets when
2378 debugging a program using the Ravenscar Profile. For more information,
2379 see the "Tasking Support when using the Ravenscar Profile" section
2380 in the GDB user manual.
2382 * Guile support was removed.
2384 * New features in the GNU simulator
2386 ** The --map-info flag lists all known core mappings.
2388 ** CFI flashes may be simulated via the "cfi" device.
2390 *** Changes in GDB 7.2
2392 * Shared library support for remote targets by default
2394 When GDB is configured for a generic, non-OS specific target, like
2395 for example, --target=arm-eabi or one of the many *-*-elf targets,
2396 GDB now queries remote stubs for loaded shared libraries using the
2397 `qXfer:libraries:read' packet. Previously, shared library support
2398 was always disabled for such configurations.
2402 ** Argument Dependent Lookup (ADL)
2404 In C++ ADL lookup directs function search to the namespaces of its
2405 arguments even if the namespace has not been imported.
2415 Here the compiler will search for `foo' in the namespace of 'b'
2416 and find A::foo. GDB now supports this. This construct is commonly
2417 used in the Standard Template Library for operators.
2419 ** Improved User Defined Operator Support
2421 In addition to member operators, GDB now supports lookup of operators
2422 defined in a namespace and imported with a `using' directive, operators
2423 defined in the global scope, operators imported implicitly from an
2424 anonymous namespace, and the ADL operators mentioned in the previous
2426 GDB now also supports proper overload resolution for all the previously
2427 mentioned flavors of operators.
2429 ** static const class members
2431 Printing of static const class members that are initialized in the
2432 class definition has been fixed.
2434 * Windows Thread Information Block access.
2436 On Windows targets, GDB now supports displaying the Windows Thread
2437 Information Block (TIB) structure. This structure is visible either
2438 by using the new command `info w32 thread-information-block' or, by
2439 dereferencing the new convenience variable named `$_tlb', a
2440 thread-specific pointer to the TIB. This feature is also supported
2441 when remote debugging using GDBserver.
2443 * Static tracepoints
2445 Static tracepoints are calls in the user program into a tracing
2446 library. One such library is a port of the LTTng kernel tracer to
2447 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2448 When debugging with GDBserver, GDB now supports combining the GDB
2449 tracepoint machinery with such libraries. For example: the user can
2450 use GDB to probe a static tracepoint marker (a call from the user
2451 program into the tracing library) with the new "strace" command (see
2452 "New commands" below). This creates a "static tracepoint" in the
2453 breakpoint list, that can be manipulated with the same feature set
2454 as fast and regular tracepoints. E.g., collect registers, local and
2455 global variables, collect trace state variables, and define
2456 tracepoint conditions. In addition, the user can collect extra
2457 static tracepoint marker specific data, by collecting the new
2458 $_sdata internal variable. When analyzing the trace buffer, you can
2459 inspect $_sdata like any other variable available to GDB. For more
2460 information, see the "Tracepoints" chapter in GDB user manual. New
2461 remote packets have been defined to support static tracepoints, see
2462 the "New remote packets" section below.
2464 * Better reconstruction of tracepoints after disconnected tracing
2466 GDB will attempt to download the original source form of tracepoint
2467 definitions when starting a trace run, and then will upload these
2468 upon reconnection to the target, resulting in a more accurate
2469 reconstruction of the tracepoints that are in use on the target.
2473 You can now exercise direct control over the ways that GDB can
2474 affect your program. For instance, you can disallow the setting of
2475 breakpoints, so that the program can run continuously (assuming
2476 non-stop mode). In addition, the "observer" variable is available
2477 to switch all of the different controls; in observer mode, GDB
2478 cannot affect the target's behavior at all, which is useful for
2479 tasks like diagnosing live systems in the field.
2481 * The new convenience variable $_thread holds the number of the
2484 * New remote packets
2488 Return the address of the Windows Thread Information Block of a given thread.
2492 In response to several of the tracepoint packets, the target may now
2493 also respond with a number of intermediate `qRelocInsn' request
2494 packets before the final result packet, to have GDB handle
2495 relocating an instruction to execute at a different address. This
2496 is particularly useful for stubs that support fast tracepoints. GDB
2497 reports support for this feature in the qSupported packet.
2501 List static tracepoint markers in the target program.
2505 List static tracepoint markers at a given address in the target
2508 qXfer:statictrace:read
2510 Read the static trace data collected (by a `collect $_sdata'
2511 tracepoint action). The remote stub reports support for this packet
2512 to gdb's qSupported query.
2516 Send the current settings of GDB's permission flags.
2520 Send part of the source (textual) form of a tracepoint definition,
2521 which includes location, conditional, and action list.
2523 * The source command now accepts a -s option to force searching for the
2524 script in the source search path even if the script name specifies
2527 * New features in the GDB remote stub, GDBserver
2529 - GDBserver now support tracepoints (including fast tracepoints, and
2530 static tracepoints). The feature is currently supported by the
2531 i386-linux and amd64-linux builds. See the "Tracepoints support
2532 in gdbserver" section in the manual for more information.
2534 GDBserver JIT compiles the tracepoint's conditional agent
2535 expression bytecode into native code whenever possible for low
2536 overhead dynamic tracepoints conditionals. For such tracepoints,
2537 an expression that examines program state is evaluated when the
2538 tracepoint is reached, in order to determine whether to capture
2539 trace data. If the condition is simple and false, processing the
2540 tracepoint finishes very quickly and no data is gathered.
2542 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2543 for static tracepoints support.
2545 - GDBserver now supports x86_64 Windows 64-bit debugging.
2547 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2548 it understands register description.
2550 * The --batch flag now disables pagination and queries.
2552 * X86 general purpose registers
2554 GDB now supports reading/writing byte, word and double-word x86
2555 general purpose registers directly. This means you can use, say,
2556 $ah or $ax to refer, respectively, to the byte register AH and
2557 16-bit word register AX that are actually portions of the 32-bit
2558 register EAX or 64-bit register RAX.
2560 * The `commands' command now accepts a range of breakpoints to modify.
2561 A plain `commands' following a command that creates multiple
2562 breakpoints affects all the breakpoints set by that command. This
2563 applies to breakpoints set by `rbreak', and also applies when a
2564 single `break' command creates multiple breakpoints (e.g.,
2565 breakpoints on overloaded c++ functions).
2567 * The `rbreak' command now accepts a filename specification as part of
2568 its argument, limiting the functions selected by the regex to those
2569 in the specified file.
2571 * Support for remote debugging Windows and SymbianOS shared libraries
2572 from Unix hosts has been improved. Non Windows GDB builds now can
2573 understand target reported file names that follow MS-DOS based file
2574 system semantics, such as file names that include drive letters and
2575 use the backslash character as directory separator. This makes it
2576 possible to transparently use the "set sysroot" and "set
2577 solib-search-path" on Unix hosts to point as host copies of the
2578 target's shared libraries. See the new command "set
2579 target-file-system-kind" described below, and the "Commands to
2580 specify files" section in the user manual for more information.
2584 eval template, expressions...
2585 Convert the values of one or more expressions under the control
2586 of the string template to a command line, and call it.
2588 set target-file-system-kind unix|dos-based|auto
2589 show target-file-system-kind
2590 Set or show the assumed file system kind for target reported file
2593 save breakpoints <filename>
2594 Save all current breakpoint definitions to a file suitable for use
2595 in a later debugging session. To read the saved breakpoint
2596 definitions, use the `source' command.
2598 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2601 info static-tracepoint-markers
2602 Display information about static tracepoint markers in the target.
2604 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2605 Define a static tracepoint by probing a marker at the given
2606 function, line, address, or marker ID.
2610 Enable and disable observer mode.
2612 set may-write-registers on|off
2613 set may-write-memory on|off
2614 set may-insert-breakpoints on|off
2615 set may-insert-tracepoints on|off
2616 set may-insert-fast-tracepoints on|off
2617 set may-interrupt on|off
2618 Set individual permissions for GDB effects on the target. Note that
2619 some of these settings can have undesirable or surprising
2620 consequences, particularly when changed in the middle of a session.
2621 For instance, disabling the writing of memory can prevent
2622 breakpoints from being inserted, cause single-stepping to fail, or
2623 even crash your program, if you disable after breakpoints have been
2624 inserted. However, GDB should not crash.
2626 set record memory-query on|off
2627 show record memory-query
2628 Control whether to stop the inferior if memory changes caused
2629 by an instruction cannot be recorded.
2634 The disassemble command now supports "start,+length" form of two arguments.
2638 ** GDB now provides a new directory location, called the python directory,
2639 where Python scripts written for GDB can be installed. The location
2640 of that directory is <data-directory>/python, where <data-directory>
2641 is the GDB data directory. For more details, see section `Scripting
2642 GDB using Python' in the manual.
2644 ** The GDB Python API now has access to breakpoints, symbols, symbol
2645 tables, program spaces, inferiors, threads and frame's code blocks.
2646 Additionally, GDB Parameters can now be created from the API, and
2647 manipulated via set/show in the CLI.
2649 ** New functions gdb.target_charset, gdb.target_wide_charset,
2650 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2652 ** New exception gdb.GdbError.
2654 ** Pretty-printers are now also looked up in the current program space.
2656 ** Pretty-printers can now be individually enabled and disabled.
2658 ** GDB now looks for names of Python scripts to auto-load in a
2659 special section named `.debug_gdb_scripts', in addition to looking
2660 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2662 * Tracepoint actions were unified with breakpoint commands. In particular,
2663 there are no longer differences in "info break" output for breakpoints and
2664 tracepoints and the "commands" command can be used for both tracepoints and
2665 regular breakpoints.
2669 ARM Symbian arm*-*-symbianelf*
2671 * D language support.
2672 GDB now supports debugging programs written in the D programming
2675 * GDB now supports the extended ptrace interface for PowerPC which is
2676 available since Linux kernel version 2.6.34. This automatically enables
2677 any hardware breakpoints and additional hardware watchpoints available in
2678 the processor. The old ptrace interface exposes just one hardware
2679 watchpoint and no hardware breakpoints.
2681 * GDB is now able to use the Data Value Compare (DVC) register available on
2682 embedded PowerPC processors to implement in hardware simple watchpoint
2683 conditions of the form:
2685 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2687 This works in native GDB running on Linux kernels with the extended ptrace
2688 interface mentioned above.
2690 *** Changes in GDB 7.1
2694 ** Namespace Support
2696 GDB now supports importing of namespaces in C++. This enables the
2697 user to inspect variables from imported namespaces. Support for
2698 namepace aliasing has also been added. So, if a namespace is
2699 aliased in the current scope (e.g. namepace C=A; ) the user can
2700 print variables using the alias (e.g. (gdb) print C::x).
2704 All known bugs relating to the printing of virtual base class were
2705 fixed. It is now possible to call overloaded static methods using a
2710 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2711 and reinterpret_cast<> are now handled by the C++ expression parser.
2715 Xilinx MicroBlaze microblaze-*-*
2720 Xilinx MicroBlaze microblaze
2723 * Multi-program debugging.
2725 GDB now has support for multi-program (a.k.a. multi-executable or
2726 multi-exec) debugging. This allows for debugging multiple inferiors
2727 simultaneously each running a different program under the same GDB
2728 session. See "Debugging Multiple Inferiors and Programs" in the
2729 manual for more information. This implied some user visible changes
2730 in the multi-inferior support. For example, "info inferiors" now
2731 lists inferiors that are not running yet or that have exited
2732 already. See also "New commands" and "New options" below.
2734 * New tracing features
2736 GDB's tracepoint facility now includes several new features:
2738 ** Trace state variables
2740 GDB tracepoints now include support for trace state variables, which
2741 are variables managed by the target agent during a tracing
2742 experiment. They are useful for tracepoints that trigger each
2743 other, so for instance one tracepoint can count hits in a variable,
2744 and then a second tracepoint has a condition that is true when the
2745 count reaches a particular value. Trace state variables share the
2746 $-syntax of GDB convenience variables, and can appear in both
2747 tracepoint actions and condition expressions. Use the "tvariable"
2748 command to create, and "info tvariables" to view; see "Trace State
2749 Variables" in the manual for more detail.
2753 GDB now includes an option for defining fast tracepoints, which
2754 targets may implement more efficiently, such as by installing a jump
2755 into the target agent rather than a trap instruction. The resulting
2756 speedup can be by two orders of magnitude or more, although the
2757 tradeoff is that some program locations on some target architectures
2758 might not allow fast tracepoint installation, for instance if the
2759 instruction to be replaced is shorter than the jump. To request a
2760 fast tracepoint, use the "ftrace" command, with syntax identical to
2761 the regular trace command.
2763 ** Disconnected tracing
2765 It is now possible to detach GDB from the target while it is running
2766 a trace experiment, then reconnect later to see how the experiment
2767 is going. In addition, a new variable disconnected-tracing lets you
2768 tell the target agent whether to continue running a trace if the
2769 connection is lost unexpectedly.
2773 GDB now has the ability to save the trace buffer into a file, and
2774 then use that file as a target, similarly to you can do with
2775 corefiles. You can select trace frames, print data that was
2776 collected in them, and use tstatus to display the state of the
2777 tracing run at the moment that it was saved. To create a trace
2778 file, use "tsave <filename>", and to use it, do "target tfile
2781 ** Circular trace buffer
2783 You can ask the target agent to handle the trace buffer as a
2784 circular buffer, discarding the oldest trace frames to make room for
2785 newer ones, by setting circular-trace-buffer to on. This feature may
2786 not be available for all target agents.
2791 The disassemble command, when invoked with two arguments, now requires
2792 the arguments to be comma-separated.
2795 The info variables command now displays variable definitions. Files
2796 which only declare a variable are not shown.
2799 The source command is now capable of sourcing Python scripts.
2800 This feature is dependent on the debugger being build with Python
2803 Related to this enhancement is also the introduction of a new command
2804 "set script-extension" (see below).
2806 * New commands (for set/show, see "New options" below)
2808 record save [<FILENAME>]
2809 Save a file (in core file format) containing the process record
2810 execution log for replay debugging at a later time.
2812 record restore <FILENAME>
2813 Restore the process record execution log that was saved at an
2814 earlier time, for replay debugging.
2816 add-inferior [-copies <N>] [-exec <FILENAME>]
2819 clone-inferior [-copies <N>] [ID]
2820 Make a new inferior ready to execute the same program another
2821 inferior has loaded.
2826 maint info program-spaces
2827 List the program spaces loaded into GDB.
2829 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2830 show remote interrupt-sequence
2831 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2832 as the sequence to the remote target in order to interrupt the execution.
2833 Ctrl-C is a default. Some system prefers BREAK which is high level of
2834 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2835 Magic SysRq g. It is BREAK signal and character 'g'.
2837 set remote interrupt-on-connect [on | off]
2838 show remote interrupt-on-connect
2839 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2840 remote target when gdb connects to it. This is needed when you debug
2843 set remotebreak [on | off]
2845 Deprecated. Use "set/show remote interrupt-sequence" instead.
2847 tvariable $NAME [ = EXP ]
2848 Create or modify a trace state variable.
2851 List trace state variables and their values.
2853 delete tvariable $NAME ...
2854 Delete one or more trace state variables.
2857 Evaluate the given expressions without collecting anything into the
2858 trace buffer. (Valid in tracepoint actions only.)
2860 ftrace FN / FILE:LINE / *ADDR
2861 Define a fast tracepoint at the given function, line, or address.
2863 * New expression syntax
2865 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2866 GDB now parses 0b101010 identically with 42.
2870 set follow-exec-mode new|same
2871 show follow-exec-mode
2872 Control whether GDB reuses the same inferior across an exec call or
2873 creates a new one. This is useful to be able to restart the old
2874 executable after the inferior having done an exec call.
2876 set default-collect EXPR, ...
2877 show default-collect
2878 Define a list of expressions to be collected at each tracepoint.
2879 This is a useful way to ensure essential items are not overlooked,
2880 such as registers or a critical global variable.
2882 set disconnected-tracing
2883 show disconnected-tracing
2884 If set to 1, the target is instructed to continue tracing if it
2885 loses its connection to GDB. If 0, the target is to stop tracing
2888 set circular-trace-buffer
2889 show circular-trace-buffer
2890 If set to on, the target is instructed to use a circular trace buffer
2891 and discard the oldest trace frames instead of stopping the trace due
2892 to a full trace buffer. If set to off, the trace stops when the buffer
2893 fills up. Some targets may not support this.
2895 set script-extension off|soft|strict
2896 show script-extension
2897 If set to "off", the debugger does not perform any script language
2898 recognition, and all sourced files are assumed to be GDB scripts.
2899 If set to "soft" (the default), files are sourced according to
2900 filename extension, falling back to GDB scripts if the first
2902 If set to "strict", files are sourced according to filename extension.
2904 set ada trust-PAD-over-XVS on|off
2905 show ada trust-PAD-over-XVS
2906 If off, activate a workaround against a bug in the debugging information
2907 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2908 the GCC sources for more information about the GNAT encoding and
2909 PAD types in particular). It is always safe to set this option to
2910 off, but this introduces a slight performance penalty. The default
2913 * Python API Improvements
2915 ** GDB provides the new class gdb.LazyString. This is useful in
2916 some pretty-printing cases. The new method gdb.Value.lazy_string
2917 provides a simple way to create objects of this type.
2919 ** The fields returned by gdb.Type.fields now have an
2920 `is_base_class' attribute.
2922 ** The new method gdb.Type.range returns the range of an array type.
2924 ** The new method gdb.parse_and_eval can be used to parse and
2925 evaluate an expression.
2927 * New remote packets
2930 Define a trace state variable.
2933 Get the current value of a trace state variable.
2936 Set desired tracing behavior upon disconnection.
2939 Set the trace buffer to be linear or circular.
2942 Get data about the tracepoints currently in use.
2946 Process record now works correctly with hardware watchpoints.
2948 Multiple bug fixes have been made to the mips-irix port, making it
2949 much more reliable. In particular:
2950 - Debugging threaded applications is now possible again. Previously,
2951 GDB would hang while starting the program, or while waiting for
2952 the program to stop at a breakpoint.
2953 - Attaching to a running process no longer hangs.
2954 - An error occurring while loading a core file has been fixed.
2955 - Changing the value of the PC register now works again. This fixes
2956 problems observed when using the "jump" command, or when calling
2957 a function from GDB, or even when assigning a new value to $pc.
2958 - With the "finish" and "return" commands, the return value for functions
2959 returning a small array is now correctly printed.
2960 - It is now possible to break on shared library code which gets executed
2961 during a shared library init phase (code executed while executing
2962 their .init section). Previously, the breakpoint would have no effect.
2963 - GDB is now able to backtrace through the signal handler for
2964 non-threaded programs.
2966 PIE (Position Independent Executable) programs debugging is now supported.
2967 This includes debugging execution of PIC (Position Independent Code) shared
2968 libraries although for that, it should be possible to run such libraries as an
2971 *** Changes in GDB 7.0
2973 * GDB now has an interface for JIT compilation. Applications that
2974 dynamically generate code can create symbol files in memory and register
2975 them with GDB. For users, the feature should work transparently, and
2976 for JIT developers, the interface is documented in the GDB manual in the
2977 "JIT Compilation Interface" chapter.
2979 * Tracepoints may now be conditional. The syntax is as for
2980 breakpoints; either an "if" clause appended to the "trace" command,
2981 or the "condition" command is available. GDB sends the condition to
2982 the target for evaluation using the same bytecode format as is used
2983 for tracepoint actions.
2985 * The disassemble command now supports: an optional /r modifier, print the
2986 raw instructions in hex as well as in symbolic form, and an optional /m
2987 modifier to print mixed source+assembly.
2989 * Process record and replay
2991 In a architecture environment that supports ``process record and
2992 replay'', ``process record and replay'' target can record a log of
2993 the process execution, and replay it with both forward and reverse
2996 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2997 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2998 set execution-direction {forward|reverse}, for targets that support
3001 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3002 feature is available with a native GDB running on kernel version
3005 * GDB now has support for multi-byte and wide character sets on the
3006 target. Strings whose character type is wchar_t, char16_t, or
3007 char32_t are now correctly printed. GDB supports wide- and unicode-
3008 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3009 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3010 `printf'. This feature requires iconv to work properly; if your
3011 system does not have a working iconv, GDB can use GNU libiconv. See
3012 the installation instructions for more information.
3014 * GDB now supports automatic retrieval of shared library files from
3015 remote targets. To use this feature, specify a system root that begins
3016 with the `remote:' prefix, either via the `set sysroot' command or via
3017 the `--with-sysroot' configure-time option.
3019 * "info sharedlibrary" now takes an optional regex of libraries to show,
3020 and it now reports if a shared library has no debugging information.
3022 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3023 now complete on file names.
3025 * When completing in expressions, gdb will attempt to limit
3026 completions to allowable structure or union fields, where appropriate.
3027 For instance, consider:
3029 # struct example { int f1; double f2; };
3030 # struct example variable;
3033 If the user types TAB at the end of this command line, the available
3034 completions will be "f1" and "f2".
3036 * Inlined functions are now supported. They show up in backtraces, and
3037 the "step", "next", and "finish" commands handle them automatically.
3039 * GDB now supports the token-splicing (##) and stringification (#)
3040 operators when expanding macros. It also supports variable-arity
3043 * GDB now supports inspecting extra signal information, exported by
3044 the new $_siginfo convenience variable. The feature is currently
3045 implemented on linux ARM, i386 and amd64.
3047 * GDB can now display the VFP floating point registers and NEON vector
3048 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3049 can provide these registers (requires Linux 2.6.30 or later). Remote
3050 and simulator targets may also provide them.
3052 * New remote packets
3055 Search memory for a sequence of bytes.
3058 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3059 operation over reliable transport links. Use of this packet is
3060 controlled by the `set remote noack-packet' command.
3063 Kill the process with the specified process ID. Use this in preference
3064 to `k' when multiprocess protocol extensions are supported.
3067 Obtains additional operating system information
3071 Read or write additional signal information.
3073 * Removed remote protocol undocumented extension
3075 An undocumented extension to the remote protocol's `S' stop reply
3076 packet that permited the stub to pass a process id was removed.
3077 Remote servers should use the `T' stop reply packet instead.
3079 * GDB now supports multiple function calling conventions according to the
3080 DWARF-2 DW_AT_calling_convention function attribute.
3082 * The SH target utilizes the aforementioned change to distinguish between gcc
3083 and Renesas calling convention. It also adds the new CLI commands
3084 `set/show sh calling-convention'.
3086 * GDB can now read compressed debug sections, as produced by GNU gold
3087 with the --compress-debug-sections=zlib flag.
3089 * 64-bit core files are now supported on AIX.
3091 * Thread switching is now supported on Tru64.
3093 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3094 which will be allocated using malloc later in program execution.
3096 * The qXfer:libraries:read remote procotol packet now allows passing a
3097 list of section offsets.
3099 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3100 conditions handling signals delivered during attach or thread creation
3101 have also been fixed.
3103 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3104 From the user's standpoint, all unqualified instances of True and False
3105 are treated as the standard definitions, regardless of context.
3107 * GDB now parses C++ symbol and type names more flexibly. For
3110 template<typename T> class C { };
3113 GDB will now correctly handle all of:
3115 ptype C<char const *>
3116 ptype C<char const*>
3117 ptype C<const char *>
3118 ptype C<const char*>
3120 * New features in the GDB remote stub, gdbserver
3122 - The "--wrapper" command-line argument tells gdbserver to use a
3123 wrapper program to launch programs for debugging.
3125 - On PowerPC and S/390 targets, it is now possible to use a single
3126 gdbserver executable to debug both 32-bit and 64-bit programs.
3127 (This requires gdbserver itself to be built as a 64-bit executable.)
3129 - gdbserver uses the new noack protocol mode for TCP connections to
3130 reduce communications latency, if also supported and enabled in GDB.
3132 - Support for the sparc64-linux-gnu target is now included in
3135 - The amd64-linux build of gdbserver now supports debugging both
3136 32-bit and 64-bit programs.
3138 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3139 now support hardware watchpoints, and will use them automatically
3144 GDB now has support for scripting using Python. Whether this is
3145 available is determined at configure time.
3147 New GDB commands can now be written in Python.
3149 * Ada tasking support
3151 Ada tasks can now be inspected in GDB. The following commands have
3155 Print the list of Ada tasks.
3157 Print detailed information about task number N.
3159 Print the task number of the current task.
3161 Switch the context of debugging to task number N.
3163 * Support for user-defined prefixed commands. The "define" command can
3164 add new commands to existing prefixes, e.g. "target".
3166 * Multi-inferior, multi-process debugging.
3168 GDB now has generalized support for multi-inferior debugging. See
3169 "Debugging Multiple Inferiors" in the manual for more information.
3170 Although availability still depends on target support, the command
3171 set is more uniform now. The GNU/Linux specific multi-forks support
3172 has been migrated to this new framework. This implied some user
3173 visible changes; see "New commands" and also "Removed commands"
3176 * Target descriptions can now describe the target OS ABI. See the
3177 "Target Description Format" section in the user manual for more
3180 * Target descriptions can now describe "compatible" architectures
3181 to indicate that the target can execute applications for a different
3182 architecture in addition to those for the main target architecture.
3183 See the "Target Description Format" section in the user manual for
3186 * Multi-architecture debugging.
3188 GDB now includes general supports for debugging applications on
3189 hybrid systems that use more than one single processor architecture
3190 at the same time. Each such hybrid architecture still requires
3191 specific support to be added. The only hybrid architecture supported
3192 in this version of GDB is the Cell Broadband Engine.
3194 * GDB now supports integrated debugging of Cell/B.E. applications that
3195 use both the PPU and SPU architectures. To enable support for hybrid
3196 Cell/B.E. debugging, you need to configure GDB to support both the
3197 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3198 --enable-targets configure option.
3200 * Non-stop mode debugging.
3202 For some targets, GDB now supports an optional mode of operation in
3203 which you can examine stopped threads while other threads continue
3204 to execute freely. This is referred to as non-stop mode, with the
3205 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3206 section in the user manual for more information.
3208 To be able to support remote non-stop debugging, a remote stub needs
3209 to implement the non-stop mode remote protocol extensions, as
3210 described in the "Remote Non-Stop" section of the user manual. The
3211 GDB remote stub, gdbserver, has been adjusted to support these
3212 extensions on linux targets.
3214 * New commands (for set/show, see "New options" below)
3216 catch syscall [NAME(S) | NUMBER(S)]
3217 Catch system calls. Arguments, which should be names of system
3218 calls or their numbers, mean catch only those syscalls. Without
3219 arguments, every syscall will be caught. When the inferior issues
3220 any of the specified syscalls, GDB will stop and announce the system
3221 call, both when it is called and when its call returns. This
3222 feature is currently available with a native GDB running on the
3223 Linux Kernel, under the following architectures: x86, x86_64,
3224 PowerPC and PowerPC64.
3226 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3228 Search memory for a sequence of bytes.
3230 maint set python print-stack
3231 maint show python print-stack
3232 Show a stack trace when an error is encountered in a Python script.
3235 Invoke CODE by passing it to the Python interpreter.
3240 These allow macros to be defined, undefined, and listed
3244 Show operating system information about processes.
3247 List the inferiors currently under GDB's control.
3250 Switch focus to inferior number NUM.
3253 Detach from inferior number NUM.
3256 Kill inferior number NUM.
3260 set spu stop-on-load
3261 show spu stop-on-load
3262 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3264 set spu auto-flush-cache
3265 show spu auto-flush-cache
3266 Control whether to automatically flush the software-managed cache
3267 during Cell/B.E. debugging.
3269 set sh calling-convention
3270 show sh calling-convention
3271 Control the calling convention used when calling SH target functions.
3274 show debug timestamp
3275 Control display of timestamps with GDB debugging output.
3277 set disassemble-next-line
3278 show disassemble-next-line
3279 Control display of disassembled source lines or instructions when
3282 set remote noack-packet
3283 show remote noack-packet
3284 Set/show the use of remote protocol QStartNoAckMode packet. See above
3285 under "New remote packets."
3287 set remote query-attached-packet
3288 show remote query-attached-packet
3289 Control use of remote protocol `qAttached' (query-attached) packet.
3291 set remote read-siginfo-object
3292 show remote read-siginfo-object
3293 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3296 set remote write-siginfo-object
3297 show remote write-siginfo-object
3298 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3301 set remote reverse-continue
3302 show remote reverse-continue
3303 Control use of remote protocol 'bc' (reverse-continue) packet.
3305 set remote reverse-step
3306 show remote reverse-step
3307 Control use of remote protocol 'bs' (reverse-step) packet.
3309 set displaced-stepping
3310 show displaced-stepping
3311 Control displaced stepping mode. Displaced stepping is a way to
3312 single-step over breakpoints without removing them from the debuggee.
3313 Also known as "out-of-line single-stepping".
3316 show debug displaced
3317 Control display of debugging info for displaced stepping.
3319 maint set internal-error
3320 maint show internal-error
3321 Control what GDB does when an internal error is detected.
3323 maint set internal-warning
3324 maint show internal-warning
3325 Control what GDB does when an internal warning is detected.
3330 Use a wrapper program to launch programs for debugging.
3332 set multiple-symbols (all|ask|cancel)
3333 show multiple-symbols
3334 The value of this variable can be changed to adjust the debugger behavior
3335 when an expression or a breakpoint location contains an ambiguous symbol
3336 name (an overloaded function name, for instance).
3338 set breakpoint always-inserted
3339 show breakpoint always-inserted
3340 Keep breakpoints always inserted in the target, as opposed to inserting
3341 them when resuming the target, and removing them when the target stops.
3342 This option can improve debugger performance on slow remote targets.
3344 set arm fallback-mode (arm|thumb|auto)
3345 show arm fallback-mode
3346 set arm force-mode (arm|thumb|auto)
3348 These commands control how ARM GDB determines whether instructions
3349 are ARM or Thumb. The default for both settings is auto, which uses
3350 the current CPSR value for instructions without symbols; previous
3351 versions of GDB behaved as if "set arm fallback-mode arm".
3353 set disable-randomization
3354 show disable-randomization
3355 Standalone programs run with the virtual address space randomization enabled
3356 by default on some platforms. This option keeps the addresses stable across
3357 multiple debugging sessions.
3361 Control whether other threads are stopped or not when some thread hits
3366 Requests that asynchronous execution is enabled in the target, if available.
3367 In this case, it's possible to resume target in the background, and interact
3368 with GDB while the target is running. "show target-async" displays the
3369 current state of asynchronous execution of the target.
3371 set target-wide-charset
3372 show target-wide-charset
3373 The target-wide-charset is the name of the character set that GDB
3374 uses when printing characters whose type is wchar_t.
3376 set tcp auto-retry (on|off)
3378 set tcp connect-timeout
3379 show tcp connect-timeout
3380 These commands allow GDB to retry failed TCP connections to a remote stub
3381 with a specified timeout period; this is useful if the stub is launched
3382 in parallel with GDB but may not be ready to accept connections immediately.
3384 set libthread-db-search-path
3385 show libthread-db-search-path
3386 Control list of directories which GDB will search for appropriate
3389 set schedule-multiple (on|off)
3390 show schedule-multiple
3391 Allow GDB to resume all threads of all processes or only threads of
3392 the current process.
3396 Use more aggressive caching for accesses to the stack. This improves
3397 performance of remote debugging (particularly backtraces) without
3398 affecting correctness.
3400 set interactive-mode (on|off|auto)
3401 show interactive-mode
3402 Control whether GDB runs in interactive mode (on) or not (off).
3403 When in interactive mode, GDB waits for the user to answer all
3404 queries. Otherwise, GDB does not wait and assumes the default
3405 answer. When set to auto (the default), GDB determines which
3406 mode to use based on the stdin settings.
3411 For program forks, this is replaced by the new more generic `info
3412 inferiors' command. To list checkpoints, you can still use the
3413 `info checkpoints' command, which was an alias for the `info forks'
3417 Replaced by the new `inferior' command. To switch between
3418 checkpoints, you can still use the `restart' command, which was an
3419 alias for the `fork' command.
3422 This is removed, since some targets don't have a notion of
3423 processes. To switch between processes, you can still use the
3424 `inferior' command using GDB's own inferior number.
3427 For program forks, this is replaced by the new more generic `kill
3428 inferior' command. To delete a checkpoint, you can still use the
3429 `delete checkpoint' command, which was an alias for the `delete
3433 For program forks, this is replaced by the new more generic `detach
3434 inferior' command. To detach a checkpoint, you can still use the
3435 `detach checkpoint' command, which was an alias for the `detach
3438 * New native configurations
3440 x86/x86_64 Darwin i[34567]86-*-darwin*
3442 x86_64 MinGW x86_64-*-mingw*
3446 Lattice Mico32 lm32-*
3447 x86 DICOS i[34567]86-*-dicos*
3448 x86_64 DICOS x86_64-*-dicos*
3451 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3452 (mingw32ce) debugging.
3458 These commands were actually not implemented on any target.
3460 *** Changes in GDB 6.8
3462 * New native configurations
3464 NetBSD/hppa hppa*-*netbsd*
3465 Xtensa GNU/Linux xtensa*-*-linux*
3469 NetBSD/hppa hppa*-*-netbsd*
3470 Xtensa GNU/Lunux xtensa*-*-linux*
3472 * Change in command line behavior -- corefiles vs. process ids.
3474 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3475 attaching to process NUMBER fails, GDB no longer attempts to open a
3476 core file named NUMBER. Attaching to a program using the -c option
3477 is no longer supported. Instead, use the '-p' or '--pid' options.
3479 * GDB can now be built as a native debugger for debugging Windows x86
3480 (mingw32) Portable Executable (PE) programs.
3482 * Pending breakpoints no longer change their number when their address
3485 * GDB now supports breakpoints with multiple locations,
3486 including breakpoints on C++ constructors, inside C++ templates,
3487 and in inlined functions.
3489 * GDB's ability to debug optimized code has been improved. GDB more
3490 accurately identifies function bodies and lexical blocks that occupy
3491 more than one contiguous range of addresses.
3493 * Target descriptions can now describe registers for PowerPC.
3495 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3496 registers on PowerPC targets.
3498 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3499 targets even when the libthread_db library is not available.
3501 * The GDB remote stub, gdbserver, now supports the new file transfer
3502 commands (remote put, remote get, and remote delete).
3504 * The GDB remote stub, gdbserver, now supports run and attach in
3505 extended-remote mode.
3507 * hppa*64*-*-hpux11* target broken
3508 The debugger is unable to start a program and fails with the following
3509 error: "Error trying to get information about dynamic linker".
3510 The gdb-6.7 release is also affected.
3512 * GDB now supports the --enable-targets= configure option to allow
3513 building a single GDB executable that supports multiple remote
3514 target architectures.
3516 * GDB now supports debugging C and C++ programs which use the
3517 Decimal Floating Point extension. In addition, the PowerPC target
3518 now has a set of pseudo-registers to inspect decimal float values
3519 stored in two consecutive float registers.
3521 * The -break-insert MI command can optionally create pending
3524 * Improved support for debugging Ada
3525 Many improvements to the Ada language support have been made. These
3527 - Better support for Ada2005 interface types
3528 - Improved handling of arrays and slices in general
3529 - Better support for Taft-amendment types
3530 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3532 - Improved command completion in Ada
3535 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3540 set print frame-arguments (all|scalars|none)
3541 show print frame-arguments
3542 The value of this variable can be changed to control which argument
3543 values should be printed by the debugger when displaying a frame.
3548 Transfer files to and from a remote target, and delete remote files.
3555 Transfer files to and from a remote target, and delete remote files.
3557 * New remote packets
3564 Open, close, read, write, and delete files on the remote system.
3567 Attach to an existing process on the remote system, in extended-remote
3571 Run a new process on the remote system, in extended-remote mode.
3573 *** Changes in GDB 6.7
3575 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3576 bfd, libiberty and opcodes, as revealed by static analysis donated by
3577 Coverity, Inc. (http://scan.coverity.com).
3579 * When looking up multiply-defined global symbols, GDB will now prefer the
3580 symbol definition in the current shared library if it was built using the
3581 -Bsymbolic linker option.
3583 * When the Text User Interface (TUI) is not configured, GDB will now
3584 recognize the -tui command-line option and print a message that the TUI
3587 * The GDB remote stub, gdbserver, now has lower overhead for high
3588 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3590 * GDB for MIPS targets now autodetects whether a remote target provides
3591 32-bit or 64-bit register values.
3593 * Support for C++ member pointers has been improved.
3595 * GDB now understands XML target descriptions, which specify the
3596 target's overall architecture. GDB can read a description from
3597 a local file or over the remote serial protocol.
3599 * Vectors of single-byte data use a new integer type which is not
3600 automatically displayed as character or string data.
3602 * The /s format now works with the print command. It displays
3603 arrays of single-byte integers and pointers to single-byte integers
3606 * Target descriptions can now describe target-specific registers,
3607 for architectures which have implemented the support (currently
3608 only ARM, M68K, and MIPS).
3610 * GDB and the GDB remote stub, gdbserver, now support the XScale
3613 * The GDB remote stub, gdbserver, has been updated to support
3614 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3615 has been rewritten to use the standard GDB remote protocol.
3617 * GDB can now step into C++ functions which are called through thunks.
3619 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3621 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3622 layout. It also supports a TextSeg= and DataSeg= response when only
3623 segment base addresses (rather than offsets) are available.
3625 * The /i format now outputs any trailing branch delay slot instructions
3626 immediately following the last instruction within the count specified.
3628 * The GDB remote protocol "T" stop reply packet now supports a
3629 "library" response. Combined with the new "qXfer:libraries:read"
3630 packet, this response allows GDB to debug shared libraries on targets
3631 where the operating system manages the list of loaded libraries (e.g.
3632 Windows and SymbianOS).
3634 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3635 (DLLs) on Windows and Windows CE targets.
3637 * GDB now supports a faster verification that a .debug file matches its binary
3638 according to its build-id signature, if the signature is present.
3644 Enable or disable hardware flow control (RTS/CTS) on the serial port
3645 when debugging using remote targets.
3647 set mem inaccessible-by-default
3648 show mem inaccessible-by-default
3649 If the target supplies a memory map, for instance via the remote
3650 protocol's "qXfer:memory-map:read" packet, setting this variable
3651 prevents GDB from accessing memory outside the memory map. This
3652 is useful for targets with memory mapped registers or which react
3653 badly to accesses of unmapped address space.
3655 set breakpoint auto-hw
3656 show breakpoint auto-hw
3657 If the target supplies a memory map, for instance via the remote
3658 protocol's "qXfer:memory-map:read" packet, setting this variable
3659 lets GDB use hardware breakpoints automatically for memory regions
3660 where it can not use software breakpoints. This covers both the
3661 "break" command and internal breakpoints used for other commands
3662 including "next" and "finish".
3665 catch exception unhandled
3666 Stop the program execution when Ada exceptions are raised.
3669 Stop the program execution when an Ada assertion failed.
3673 Set an alternate system root for target files. This is a more
3674 general version of "set solib-absolute-prefix", which is now
3675 an alias to "set sysroot".
3678 Provide extended SPU facility status information. This set of
3679 commands is available only when debugging the Cell/B.E. SPU
3682 * New native configurations
3684 OpenBSD/sh sh*-*openbsd*
3687 unset tdesc filename
3689 Use the specified local file as an XML target description, and do
3690 not query the target for its built-in description.
3694 OpenBSD/sh sh*-*-openbsd*
3695 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3696 Toshiba Media Processor mep-elf
3698 * New remote packets
3701 Ignore the specified signals; pass them directly to the debugged program
3702 without stopping other threads or reporting them to GDB.
3704 qXfer:features:read:
3705 Read an XML target description from the target, which describes its
3710 Read or write contents of an spufs file on the target system. These
3711 packets are available only on the Cell/B.E. SPU architecture.
3713 qXfer:libraries:read:
3714 Report the loaded shared libraries. Combined with new "T" packet
3715 response, this packet allows GDB to debug shared libraries on
3716 targets where the operating system manages the list of loaded
3717 libraries (e.g. Windows and SymbianOS).
3721 Support for these obsolete configurations has been removed.
3729 i[34567]86-*-lynxos*
3730 i[34567]86-*-netware*
3731 i[34567]86-*-sco3.2v5*
3732 i[34567]86-*-sco3.2v4*
3734 i[34567]86-*-sysv4.2*
3737 i[34567]86-*-unixware2*
3738 i[34567]86-*-unixware*
3747 * Other removed features
3754 Various m68k-only ROM monitors.
3761 Various Renesas ROM monitors and debugging interfaces for SH and
3766 Support for a Macraigor serial interface to on-chip debugging.
3767 GDB does not directly support the newer parallel or USB
3772 A debug information format. The predecessor to DWARF 2 and
3773 DWARF 3, which are still supported.
3775 Support for the HP aCC compiler on HP-UX/PA-RISC
3777 SOM-encapsulated symbolic debugging information, automatic
3778 invocation of pxdb, and the aCC custom C++ ABI. This does not
3779 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3780 with aCC can still be debugged on an assembly level.
3782 MIPS ".pdr" sections
3784 A MIPS-specific format used to describe stack frame layout
3785 in debugging information.
3789 GDB could work with an older version of Guile to debug
3790 the interpreter and Scheme programs running in it.
3792 set mips stack-arg-size
3793 set mips saved-gpreg-size
3795 Use "set mips abi" to control parameter passing for MIPS.
3797 *** Changes in GDB 6.6
3802 Cell Broadband Engine SPU spu-elf
3804 * GDB can now be configured as a cross-debugger targeting native Windows
3805 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3806 running on a Windows system over TCP/IP to debug Windows programs.
3808 * The GDB remote stub, gdbserver, has been updated to support Windows and
3809 Cygwin debugging. Both single-threaded and multi-threaded programs are
3812 * The "set trust-readonly-sections" command works again. This command was
3813 broken in GDB 6.3, 6.4, and 6.5.
3815 * The "load" command now supports writing to flash memory, if the remote
3816 stub provides the required support.
3818 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3819 longer requires symbolic debug information (e.g. DWARF-2).
3824 unset substitute-path
3825 show substitute-path
3826 Manage a list of substitution rules that GDB uses to rewrite the name
3827 of the directories where the sources are located. This can be useful
3828 for instance when the sources were moved to a different location
3829 between compilation and debugging.
3833 Print each CLI command as it is executed. Each command is prefixed with
3834 a number of `+' symbols representing the nesting depth.
3835 The source command now has a `-v' option to enable the same feature.
3839 The ARM Demon monitor support (RDP protocol, "target rdp").
3841 Kernel Object Display, an embedded debugging feature which only worked with
3842 an obsolete version of Cisco IOS.
3844 The 'set download-write-size' and 'show download-write-size' commands.
3846 * New remote packets
3849 Tell a stub about GDB client features, and request remote target features.
3850 The first feature implemented is PacketSize, which allows the target to
3851 specify the size of packets it can handle - to minimize the number of
3852 packets required and improve performance when connected to a remote
3856 Fetch an OS auxilliary vector from the remote stub. This packet is a
3857 more efficient replacement for qPart:auxv:read.
3859 qXfer:memory-map:read:
3860 Fetch a memory map from the remote stub, including information about
3861 RAM, ROM, and flash memory devices.
3866 Erase and program a flash memory device.
3868 * Removed remote packets
3871 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3872 used it, and only gdbserver implemented it.
3874 *** Changes in GDB 6.5
3878 Renesas M32C/M16C m32c-elf
3880 Morpho Technologies ms1 ms1-elf
3884 init-if-undefined Initialize a convenience variable, but
3885 only if it doesn't already have a value.
3887 The following commands are presently only implemented for native GNU/Linux:
3889 checkpoint Save a snapshot of the program state.
3891 restart <n> Return the program state to a
3892 previously saved state.
3894 info checkpoints List currently saved checkpoints.
3896 delete-checkpoint <n> Delete a previously saved checkpoint.
3898 set|show detach-on-fork Tell gdb whether to detach from a newly
3899 forked process, or to keep debugging it.
3901 info forks List forks of the user program that
3902 are available to be debugged.
3904 fork <n> Switch to debugging one of several
3905 forks of the user program that are
3906 available to be debugged.
3908 delete-fork <n> Delete a fork from the list of forks
3909 that are available to be debugged (and
3910 kill the forked process).
3912 detach-fork <n> Delete a fork from the list of forks
3913 that are available to be debugged (and
3914 allow the process to continue).
3918 Morpho Technologies ms2 ms1-elf
3920 * Improved Windows host support
3922 GDB now builds as a cross debugger hosted on i686-mingw32, including
3923 native console support, and remote communications using either
3924 network sockets or serial ports.
3926 * Improved Modula-2 language support
3928 GDB can now print most types in the Modula-2 syntax. This includes:
3929 basic types, set types, record types, enumerated types, range types,
3930 pointer types and ARRAY types. Procedure var parameters are correctly
3931 printed and hexadecimal addresses and character constants are also
3932 written in the Modula-2 syntax. Best results can be obtained by using
3933 GNU Modula-2 together with the -gdwarf-2 command line option.
3937 The ARM rdi-share module.
3939 The Netware NLM debug server.
3941 *** Changes in GDB 6.4
3943 * New native configurations
3945 OpenBSD/arm arm*-*-openbsd*
3946 OpenBSD/mips64 mips64-*-openbsd*
3950 Morpho Technologies ms1 ms1-elf
3952 * New command line options
3954 --batch-silent As for --batch, but totally silent.
3955 --return-child-result The debugger will exist with the same value
3956 the child (debugged) program exited with.
3957 --eval-command COMMAND, -ex COMMAND
3958 Execute a single GDB CLI command. This may be
3959 specified multiple times and in conjunction
3960 with the --command (-x) option.
3962 * Deprecated commands removed
3964 The following commands, that were deprecated in 2000, have been
3968 set|show arm disassembly-flavor set|show arm disassembler
3969 othernames set arm disassembler
3970 set|show remotedebug set|show debug remote
3971 set|show archdebug set|show debug arch
3972 set|show eventdebug set|show debug event
3975 * New BSD user-level threads support
3977 It is now possible to debug programs using the user-level threads
3978 library on OpenBSD and FreeBSD. Currently supported (target)
3981 FreeBSD/amd64 x86_64-*-freebsd*
3982 FreeBSD/i386 i386-*-freebsd*
3983 OpenBSD/i386 i386-*-openbsd*
3985 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3986 are not yet supported.
3988 * New support for Matsushita MN10300 w/sim added
3989 (Work in progress). mn10300-elf.
3991 * REMOVED configurations and files
3993 VxWorks and the XDR protocol *-*-vxworks
3994 Motorola MCORE mcore-*-*
3995 National Semiconductor NS32000 ns32k-*-*
3997 * New "set print array-indexes" command
3999 After turning this setting "on", GDB prints the index of each element
4000 when displaying arrays. The default is "off" to preserve the previous
4003 * VAX floating point support
4005 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4007 * User-defined command support
4009 In addition to using $arg0..$arg9 for argument passing, it is now possible
4010 to use $argc to determine now many arguments have been passed. See the
4011 section on user-defined commands in the user manual for more information.
4013 *** Changes in GDB 6.3:
4015 * New command line option
4017 GDB now accepts -l followed by a number to set the timeout for remote
4020 * GDB works with GCC -feliminate-dwarf2-dups
4022 GDB now supports a more compact representation of DWARF-2 debug
4023 information using DW_FORM_ref_addr references. These are produced
4024 by GCC with the option -feliminate-dwarf2-dups and also by some
4025 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4026 to use -feliminate-dwarf2-dups.
4028 * Internationalization
4030 When supported by the host system, GDB will be built with
4031 internationalization (libintl). The task of marking up the sources is
4032 continued, we're looking forward to our first translation.
4036 Initial support for debugging programs compiled with the GNAT
4037 implementation of the Ada programming language has been integrated
4038 into GDB. In this release, support is limited to expression evaluation.
4040 * New native configurations
4042 GNU/Linux/m32r m32r-*-linux-gnu
4046 GDB's remote protocol now includes support for the 'p' packet. This
4047 packet is used to fetch individual registers from a remote inferior.
4049 * END-OF-LIFE registers[] compatibility module
4051 GDB's internal register infrastructure has been completely rewritten.
4052 The new infrastructure making possible the implementation of key new
4053 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4056 GDB 6.3 will be the last release to include the the registers[]
4057 compatibility module that allowed out-of-date configurations to
4058 continue to work. This change directly impacts the following
4068 powerpc bdm protocol
4070 Unless there is activity to revive these configurations, they will be
4071 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4073 * OBSOLETE configurations and files
4075 Configurations that have been declared obsolete in this release have
4076 been commented out. Unless there is activity to revive these
4077 configurations, the next release of GDB will have their sources
4078 permanently REMOVED.
4087 *** Changes in GDB 6.2.1:
4089 * MIPS `break main; run' gave an heuristic-fence-post warning
4091 When attempting to run even a simple program, a warning about
4092 heuristic-fence-post being hit would be reported. This problem has
4095 * MIPS IRIX 'long double' crashed GDB
4097 When examining a long double variable, GDB would get a segmentation
4098 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4099 IRIX long double values).
4103 A bug in the VAX stack code was causing problems with the "next"
4104 command. This problem has been fixed.
4106 *** Changes in GDB 6.2:
4108 * Fix for ``many threads''
4110 On GNU/Linux systems that use the NPTL threads library, a program
4111 rapidly creating and deleting threads would confuse GDB leading to the
4114 ptrace: No such process.
4115 thread_db_get_info: cannot get thread info: generic error
4117 This problem has been fixed.
4119 * "-async" and "-noasync" options removed.
4121 Support for the broken "-noasync" option has been removed (it caused
4124 * New ``start'' command.
4126 This command runs the program until the begining of the main procedure.
4128 * New BSD Kernel Data Access Library (libkvm) interface
4130 Using ``target kvm'' it is now possible to debug kernel core dumps and
4131 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4132 platforms. Currently supported (native-only) configurations are:
4134 FreeBSD/amd64 x86_64-*-freebsd*
4135 FreeBSD/i386 i?86-*-freebsd*
4136 NetBSD/i386 i?86-*-netbsd*
4137 NetBSD/m68k m68*-*-netbsd*
4138 NetBSD/sparc sparc-*-netbsd*
4139 OpenBSD/amd64 x86_64-*-openbsd*
4140 OpenBSD/i386 i?86-*-openbsd*
4141 OpenBSD/m68k m68*-openbsd*
4142 OpenBSD/sparc sparc-*-openbsd*
4144 * Signal trampoline code overhauled
4146 Many generic problems with GDB's signal handling code have been fixed.
4147 These include: backtraces through non-contiguous stacks; recognition
4148 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4149 call; backtrace through a signal trampoline; step into and out of
4150 signal handlers; and single-stepping in the signal trampoline.
4152 Please note that kernel bugs are a limiting factor here. These
4153 features have been shown to work on an s390 GNU/Linux system that
4154 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4156 * Cygwin support for DWARF 2 added.
4158 * New native configurations
4160 GNU/Linux/hppa hppa*-*-linux*
4161 OpenBSD/hppa hppa*-*-openbsd*
4162 OpenBSD/m68k m68*-*-openbsd*
4163 OpenBSD/m88k m88*-*-openbsd*
4164 OpenBSD/powerpc powerpc-*-openbsd*
4165 NetBSD/vax vax-*-netbsd*
4166 OpenBSD/vax vax-*-openbsd*
4168 * END-OF-LIFE frame compatibility module
4170 GDB's internal frame infrastructure has been completely rewritten.
4171 The new infrastructure making it possible to support key new features
4172 including DWARF 2 Call Frame Information. To aid in the task of
4173 migrating old configurations to this new infrastructure, a
4174 compatibility module, that allowed old configurations to continue to
4175 work, was also included.
4177 GDB 6.2 will be the last release to include this frame compatibility
4178 module. This change directly impacts the following configurations:
4188 Unless there is activity to revive these configurations, they will be
4189 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4191 * REMOVED configurations and files
4193 Sun 3, running SunOS 3 m68*-*-sunos3*
4194 Sun 3, running SunOS 4 m68*-*-sunos4*
4195 Sun 2, running SunOS 3 m68000-*-sunos3*
4196 Sun 2, running SunOS 4 m68000-*-sunos4*
4197 Motorola 680x0 running LynxOS m68*-*-lynxos*
4198 AT&T 3b1/Unix pc m68*-att-*
4199 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4200 decstation mips-dec-* mips-little-*
4201 riscos mips-*-riscos* mips-*-sysv*
4202 sonymips mips-sony-*
4203 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4205 *** Changes in GDB 6.1.1:
4207 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4209 The TUI (Text-mode User Interface) is now built as part of a default
4210 GDB configuration. It is enabled by either selecting the TUI with the
4211 command line option "-i=tui" or by running the separate "gdbtui"
4212 program. For more information on the TUI, see the manual "Debugging
4215 * Pending breakpoint support (also included in GDB 6.1)
4217 Support has been added to allow you to specify breakpoints in shared
4218 libraries that have not yet been loaded. If a breakpoint location
4219 cannot be found, and the "breakpoint pending" option is set to auto,
4220 GDB queries you if you wish to make the breakpoint pending on a future
4221 shared-library load. If and when GDB resolves the breakpoint symbol,
4222 the pending breakpoint is removed as one or more regular breakpoints
4225 Pending breakpoints are very useful for GCJ Java debugging.
4227 * Fixed ISO-C build problems
4229 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4230 non ISO-C code that stopped them being built using a more strict ISO-C
4231 compiler (e.g., IBM's C compiler).
4233 * Fixed build problem on IRIX 5
4235 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4236 wasn't able to compile compile on an IRIX 5 system.
4238 * Added execute permission to gdb/gdbserver/configure
4240 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4241 permission. This bug would cause configure to fail on a number of
4242 systems (Solaris, IRIX). Ref: server/519.
4244 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4246 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4247 has been updated to use constant array sizes.
4249 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4251 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4252 its generated DWARF Call Frame Info. This encoding was causing GDB to
4253 panic, that panic has been fixed. Ref: gdb/1628.
4255 * Fixed a problem when examining parameters in shared library code.
4257 When examining parameters in optimized shared library code generated
4258 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4259 not available''. GDB now correctly displays the variable's value.
4261 *** Changes in GDB 6.1:
4263 * Removed --with-mmalloc
4265 Support for the mmalloc memory manager has been removed, as it
4266 conflicted with the internal gdb byte cache.
4268 * Changes in AMD64 configurations
4270 The AMD64 target now includes the %cs and %ss registers. As a result
4271 the AMD64 remote protocol has changed; this affects the floating-point
4272 and SSE registers. If you rely on those registers for your debugging,
4273 you should upgrade gdbserver on the remote side.
4275 * Revised SPARC target
4277 The SPARC target has been completely revised, incorporating the
4278 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4279 support for LynxOS and SunOS 4 has been dropped. Calling functions
4280 from within GDB on operating systems with a non-executable stack
4281 (Solaris, OpenBSD) now works.
4285 GDB has a new C++ demangler which does a better job on the mangled
4286 names generated by current versions of g++. It also runs faster, so
4287 with this and other changes gdb should now start faster on large C++
4290 * DWARF 2 Location Expressions
4292 GDB support for location expressions has been extended to support function
4293 arguments and frame bases. Older versions of GDB could crash when they
4296 * C++ nested types and namespaces
4298 GDB's support for nested types and namespaces in C++ has been
4299 improved, especially if you use the DWARF 2 debugging format. (This
4300 is the default for recent versions of GCC on most platforms.)
4301 Specifically, if you have a class "Inner" defined within a class or
4302 namespace "Outer", then GDB realizes that the class's name is
4303 "Outer::Inner", not simply "Inner". This should greatly reduce the
4304 frequency of complaints about not finding RTTI symbols. In addition,
4305 if you are stopped at inside of a function defined within a namespace,
4306 GDB modifies its name lookup accordingly.
4308 * New native configurations
4310 NetBSD/amd64 x86_64-*-netbsd*
4311 OpenBSD/amd64 x86_64-*-openbsd*
4312 OpenBSD/alpha alpha*-*-openbsd*
4313 OpenBSD/sparc sparc-*-openbsd*
4314 OpenBSD/sparc64 sparc64-*-openbsd*
4316 * New debugging protocols
4318 M32R with SDI protocol m32r-*-elf*
4320 * "set prompt-escape-char" command deleted.
4322 The command "set prompt-escape-char" has been deleted. This command,
4323 and its very obscure effet on GDB's prompt, was never documented,
4324 tested, nor mentioned in the NEWS file.
4326 * OBSOLETE configurations and files
4328 Configurations that have been declared obsolete in this release have
4329 been commented out. Unless there is activity to revive these
4330 configurations, the next release of GDB will have their sources
4331 permanently REMOVED.
4333 Sun 3, running SunOS 3 m68*-*-sunos3*
4334 Sun 3, running SunOS 4 m68*-*-sunos4*
4335 Sun 2, running SunOS 3 m68000-*-sunos3*
4336 Sun 2, running SunOS 4 m68000-*-sunos4*
4337 Motorola 680x0 running LynxOS m68*-*-lynxos*
4338 AT&T 3b1/Unix pc m68*-att-*
4339 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4340 decstation mips-dec-* mips-little-*
4341 riscos mips-*-riscos* mips-*-sysv*
4342 sonymips mips-sony-*
4343 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4345 * REMOVED configurations and files
4347 SGI Irix-4.x mips-sgi-irix4 or iris4
4348 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4349 Z8000 simulator z8k-zilog-none or z8ksim
4350 Matsushita MN10200 w/simulator mn10200-*-*
4351 H8/500 simulator h8500-hitachi-hms or h8500hms
4352 HP/PA running BSD hppa*-*-bsd*
4353 HP/PA running OSF/1 hppa*-*-osf*
4354 HP/PA Pro target hppa*-*-pro*
4355 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4356 386BSD i[3456]86-*-bsd*
4357 Sequent family i[3456]86-sequent-sysv4*
4358 i[3456]86-sequent-sysv*
4359 i[3456]86-sequent-bsd*
4360 SPARC running LynxOS sparc-*-lynxos*
4361 SPARC running SunOS 4 sparc-*-sunos4*
4362 Tsqware Sparclet sparclet-*-*
4363 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4365 *** Changes in GDB 6.0:
4369 Support for debugging the Objective-C programming language has been
4370 integrated into GDB.
4372 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4374 DWARF 2's Call Frame Information makes available compiler generated
4375 information that more exactly describes the program's run-time stack.
4376 By using this information, GDB is able to provide more robust stack
4379 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4380 have been updated to use a new backtrace mechanism which includes
4381 DWARF 2 CFI support.
4385 GDB's remote protocol has been extended to include support for hosted
4386 file I/O (where the remote target uses GDB's file system). See GDB's
4387 remote protocol documentation for details.
4389 * All targets using the new architecture framework.
4391 All of GDB's targets have been updated to use the new internal
4392 architecture framework. The way is now open for future GDB releases
4393 to include cross-architecture native debugging support (i386 on amd64,
4396 * GNU/Linux's Thread Local Storage (TLS)
4398 GDB now includes support for for the GNU/Linux implementation of
4399 per-thread variables.
4401 * GNU/Linux's Native POSIX Thread Library (NPTL)
4403 GDB's thread code has been updated to work with either the new
4404 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4406 * Separate debug info.
4408 GDB, in conjunction with BINUTILS, now supports a mechanism for
4409 automatically loading debug information from a separate file. Instead
4410 of shipping full debug and non-debug versions of system libraries,
4411 system integrators can now instead ship just the stripped libraries
4412 and optional debug files.
4414 * DWARF 2 Location Expressions
4416 DWARF 2 Location Expressions allow the compiler to more completely
4417 describe the location of variables (even in optimized code) to the
4420 GDB now includes preliminary support for location expressions (support
4421 for DW_OP_piece is still missing).
4425 A number of long standing bugs that caused GDB to die while starting a
4426 Java application have been fixed. GDB's Java support is now
4427 considered "useable".
4429 * GNU/Linux support for fork, vfork, and exec.
4431 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4432 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4435 * GDB supports logging output to a file
4437 There are two new commands, "set logging" and "show logging", which can be
4438 used to capture GDB's output to a file.
4440 * The meaning of "detach" has changed for gdbserver
4442 The "detach" command will now resume the application, as documented. To
4443 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4446 * d10v, m68hc11 `regs' command deprecated
4448 The `info registers' command has been updated so that it displays the
4449 registers using a format identical to the old `regs' command.
4453 A new command, "maint set profile on/off", has been added. This command can
4454 be used to enable or disable profiling while running GDB, to profile a
4455 session or a set of commands. In addition there is a new configure switch,
4456 "--enable-profiling", which will cause GDB to be compiled with profiling
4457 data, for more informative profiling results.
4459 * Default MI syntax changed to "mi2".
4461 The default MI (machine interface) syntax, enabled by the command line
4462 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4463 "mi1", can be enabled by specifying the option "-i=mi1".
4465 Support for the original "mi0" syntax (included in GDB 5.0) has been
4468 Fix for gdb/192: removed extraneous space when displaying frame level.
4469 Fix for gdb/672: update changelist is now output in mi list format.
4470 Fix for gdb/702: a -var-assign that updates the value now shows up
4471 in a subsequent -var-update.
4473 * New native configurations.
4475 FreeBSD/amd64 x86_64-*-freebsd*
4477 * Multi-arched targets.
4479 HP/PA HPUX11 hppa*-*-hpux*
4480 Renesas M32R/D w/simulator m32r-*-elf*
4482 * OBSOLETE configurations and files
4484 Configurations that have been declared obsolete in this release have
4485 been commented out. Unless there is activity to revive these
4486 configurations, the next release of GDB will have their sources
4487 permanently REMOVED.
4489 Z8000 simulator z8k-zilog-none or z8ksim
4490 Matsushita MN10200 w/simulator mn10200-*-*
4491 H8/500 simulator h8500-hitachi-hms or h8500hms
4492 HP/PA running BSD hppa*-*-bsd*
4493 HP/PA running OSF/1 hppa*-*-osf*
4494 HP/PA Pro target hppa*-*-pro*
4495 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4496 Sequent family i[3456]86-sequent-sysv4*
4497 i[3456]86-sequent-sysv*
4498 i[3456]86-sequent-bsd*
4499 Tsqware Sparclet sparclet-*-*
4500 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4502 * REMOVED configurations and files
4505 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4506 IBM AIX PS/2 i[3456]86-*-aix
4507 i386 running Mach 3.0 i[3456]86-*-mach3*
4508 i386 running Mach i[3456]86-*-mach*
4509 i386 running OSF/1 i[3456]86-*osf1mk*
4510 HP/Apollo 68k Family m68*-apollo*-sysv*,
4512 m68*-hp-bsd*, m68*-hp-hpux*
4513 Argonaut Risc Chip (ARC) arc-*-*
4514 Mitsubishi D30V d30v-*-*
4515 Fujitsu FR30 fr30-*-elf*
4516 OS/9000 i[34]86-*-os9k
4517 I960 with MON960 i960-*-coff
4519 * MIPS $fp behavior changed
4521 The convenience variable $fp, for the MIPS, now consistently returns
4522 the address of the current frame's base. Previously, depending on the
4523 context, $fp could refer to either $sp or the current frame's base
4524 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4525 The GNU Source-Level Debugger''.
4527 *** Changes in GDB 5.3:
4529 * GNU/Linux shared library multi-threaded performance improved.
4531 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4532 `/proc', in preference to `ptrace' for memory reads. This may result
4533 in an improvement in the start-up time of multi-threaded, shared
4534 library applications when run under GDB. One GDB user writes: ``loads
4535 shared libs like mad''.
4537 * ``gdbserver'' now supports multi-threaded applications on some targets
4539 Support for debugging multi-threaded applications which use
4540 the GNU/Linux LinuxThreads package has been added for
4541 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4542 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4544 * GDB now supports C/C++ preprocessor macros.
4546 GDB now expands preprocessor macro invocations in C/C++ expressions,
4547 and provides various commands for showing macro definitions and how
4550 The new command `macro expand EXPRESSION' expands any macro
4551 invocations in expression, and shows the result.
4553 The new command `show macro MACRO-NAME' shows the definition of the
4554 macro named MACRO-NAME, and where it was defined.
4556 Most compilers don't include information about macros in the debugging
4557 information by default. In GCC 3.1, for example, you need to compile
4558 your program with the options `-gdwarf-2 -g3'. If the macro
4559 information is present in the executable, GDB will read it.
4561 * Multi-arched targets.
4563 DEC Alpha (partial) alpha*-*-*
4564 DEC VAX (partial) vax-*-*
4566 National Semiconductor NS32000 (partial) ns32k-*-*
4567 Motorola 68000 (partial) m68k-*-*
4568 Motorola MCORE mcore-*-*
4572 Fujitsu FRV architecture added by Red Hat frv*-*-*
4575 * New native configurations
4577 Alpha NetBSD alpha*-*-netbsd*
4578 SH NetBSD sh*-*-netbsdelf*
4579 MIPS NetBSD mips*-*-netbsd*
4580 UltraSPARC NetBSD sparc64-*-netbsd*
4582 * OBSOLETE configurations and files
4584 Configurations that have been declared obsolete in this release have
4585 been commented out. Unless there is activity to revive these
4586 configurations, the next release of GDB will have their sources
4587 permanently REMOVED.
4589 Mitsubishi D30V d30v-*-*
4590 OS/9000 i[34]86-*-os9k
4591 IBM AIX PS/2 i[3456]86-*-aix
4592 Fujitsu FR30 fr30-*-elf*
4593 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4594 Argonaut Risc Chip (ARC) arc-*-*
4595 i386 running Mach 3.0 i[3456]86-*-mach3*
4596 i386 running Mach i[3456]86-*-mach*
4597 i386 running OSF/1 i[3456]86-*osf1mk*
4598 HP/Apollo 68k Family m68*-apollo*-sysv*,
4600 m68*-hp-bsd*, m68*-hp-hpux*
4601 I960 with MON960 i960-*-coff
4603 * OBSOLETE languages
4605 CHILL, a Pascal like language used by telecommunications companies.
4607 * REMOVED configurations and files
4609 AMD 29k family via UDI a29k-amd-udi, udi29k
4610 A29K VxWorks a29k-*-vxworks
4611 AMD 29000 embedded, using EBMON a29k-none-none
4612 AMD 29000 embedded with COFF a29k-none-coff
4613 AMD 29000 embedded with a.out a29k-none-aout
4615 testsuite/gdb.hp/gdb.threads-hp/ directory
4617 * New command "set max-user-call-depth <nnn>"
4619 This command allows the user to limit the call depth of user-defined
4620 commands. The default is 1024.
4622 * Changes in FreeBSD/i386 native debugging.
4624 Support for the "generate-core-file" has been added.
4626 * New commands "dump", "append", and "restore".
4628 These commands allow data to be copied from target memory
4629 to a bfd-format or binary file (dump and append), and back
4630 from a file into memory (restore).
4632 * Improved "next/step" support on multi-processor Alpha Tru64.
4634 The previous single-step mechanism could cause unpredictable problems,
4635 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4636 of a software single-step mechanism prevents this.
4638 *** Changes in GDB 5.2.1:
4646 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4647 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4648 Fix, by Joel Brobecker imported from mainline.
4650 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4651 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4652 Fix, by Fred Fish, imported from mainline.
4654 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4655 Surprisingly enough, it works now.
4656 By Michal Ludvig, imported from mainline.
4658 i386 hardware watchpoint support:
4659 avoid misses on second run for some targets.
4660 By Pierre Muller, imported from mainline.
4662 *** Changes in GDB 5.2:
4664 * New command "set trust-readonly-sections on[off]".
4666 This command is a hint that tells gdb that read-only sections
4667 really are read-only (ie. that their contents will not change).
4668 In this mode, gdb will go to the object file rather than the
4669 target to read memory from read-only sections (such as ".text").
4670 This can be a significant performance improvement on some
4671 (notably embedded) targets.
4673 * New command "generate-core-file" (or "gcore").
4675 This new gdb command allows the user to drop a core file of the child
4676 process state at any time. So far it's been implemented only for
4677 GNU/Linux and Solaris, but should be relatively easily ported to other
4678 hosts. Argument is core file name (defaults to core.<pid>).
4680 * New command line option
4682 GDB now accepts --pid or -p followed by a process id.
4684 * Change in command line behavior -- corefiles vs. process ids.
4686 There is a subtle behavior in the way in which GDB handles
4687 command line arguments. The first non-flag argument is always
4688 a program to debug, but the second non-flag argument may either
4689 be a corefile or a process id. Previously, GDB would attempt to
4690 open the second argument as a corefile, and if that failed, would
4691 issue a superfluous error message and then attempt to attach it as
4692 a process. Now, if the second argument begins with a non-digit,
4693 it will be treated as a corefile. If it begins with a digit,
4694 GDB will attempt to attach it as a process, and if no such process
4695 is found, will then attempt to open it as a corefile.
4697 * Changes in ARM configurations.
4699 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4700 configuration is fully multi-arch.
4702 * New native configurations
4704 ARM NetBSD arm*-*-netbsd*
4705 x86 OpenBSD i[3456]86-*-openbsd*
4706 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4707 Sparc64 running FreeBSD sparc64-*-freebsd*
4711 Sanyo XStormy16 xstormy16-elf
4713 * OBSOLETE configurations and files
4715 Configurations that have been declared obsolete in this release have
4716 been commented out. Unless there is activity to revive these
4717 configurations, the next release of GDB will have their sources
4718 permanently REMOVED.
4720 AMD 29k family via UDI a29k-amd-udi, udi29k
4721 A29K VxWorks a29k-*-vxworks
4722 AMD 29000 embedded, using EBMON a29k-none-none
4723 AMD 29000 embedded with COFF a29k-none-coff
4724 AMD 29000 embedded with a.out a29k-none-aout
4726 testsuite/gdb.hp/gdb.threads-hp/ directory
4728 * REMOVED configurations and files
4730 TI TMS320C80 tic80-*-*
4732 PowerPC Solaris powerpcle-*-solaris*
4733 PowerPC Windows NT powerpcle-*-cygwin32
4734 PowerPC Netware powerpc-*-netware*
4735 Harris/CXUX m88k m88*-harris-cxux*
4736 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4737 ns32k-utek-sysv* ns32k-utek-*
4738 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4739 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4740 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4741 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4742 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4744 * Changes to command line processing
4746 The new `--args' feature can be used to specify command-line arguments
4747 for the inferior from gdb's command line.
4749 * Changes to key bindings
4751 There is a new `operate-and-get-next' function bound to `C-o'.
4753 *** Changes in GDB 5.1.1
4755 Fix compile problem on DJGPP.
4757 Fix a problem with floating-point registers on the i386 being
4760 Fix to stop GDB crashing on .debug_str debug info.
4762 Numerous documentation fixes.
4764 Numerous testsuite fixes.
4766 *** Changes in GDB 5.1:
4768 * New native configurations
4770 Alpha FreeBSD alpha*-*-freebsd*
4771 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4772 MIPS GNU/Linux mips*-*-linux*
4773 MIPS SGI Irix 6.x mips*-sgi-irix6*
4774 ia64 AIX ia64-*-aix*
4775 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4779 Motorola 68HC11 and 68HC12 m68hc11-elf
4781 UltraSparc running GNU/Linux sparc64-*-linux*
4783 * OBSOLETE configurations and files
4785 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4786 Harris/CXUX m88k m88*-harris-cxux*
4787 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4788 ns32k-utek-sysv* ns32k-utek-*
4789 TI TMS320C80 tic80-*-*
4791 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4792 PowerPC Solaris powerpcle-*-solaris*
4793 PowerPC Windows NT powerpcle-*-cygwin32
4794 PowerPC Netware powerpc-*-netware*
4795 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4796 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4797 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4798 Apple Macintosh (MPW) host N/A
4800 stuff.c (Program to stuff files into a specially prepared space in kdb)
4801 kdb-start.c (Main loop for the standalone kernel debugger)
4803 Configurations that have been declared obsolete in this release have
4804 been commented out. Unless there is activity to revive these
4805 configurations, the next release of GDB will have their sources
4806 permanently REMOVED.
4808 * REMOVED configurations and files
4810 Altos 3068 m68*-altos-*
4811 Convex c1-*-*, c2-*-*
4813 ARM RISCix arm-*-* (as host)
4817 * GDB has been converted to ISO C.
4819 GDB's source code has been converted to ISO C. In particular, the
4820 sources are fully protoized, and rely on standard headers being
4825 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4827 * The MI enabled by default.
4829 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4830 revised and enabled by default. Packages which use GDB as a debugging
4831 engine behind a UI or another front end are encouraged to switch to
4832 using the GDB/MI interface, instead of the old annotations interface
4833 which is now deprecated.
4835 * Support for debugging Pascal programs.
4837 GDB now includes support for debugging Pascal programs. The following
4838 main features are supported:
4840 - Pascal-specific data types such as sets;
4842 - automatic recognition of Pascal sources based on file-name
4845 - Pascal-style display of data types, variables, and functions;
4847 - a Pascal expression parser.
4849 However, some important features are not yet supported.
4851 - Pascal string operations are not supported at all;
4853 - there are some problems with boolean types;
4855 - Pascal type hexadecimal constants are not supported
4856 because they conflict with the internal variables format;
4858 - support for Pascal objects and classes is not full yet;
4860 - unlike Pascal, GDB is case-sensitive for symbol names.
4862 * Changes in completion.
4864 Commands such as `shell', `run' and `set args', which pass arguments
4865 to inferior programs, now complete on file names, similar to what
4866 users expect at the shell prompt.
4868 Commands which accept locations, such as `disassemble', `print',
4869 `breakpoint', `until', etc. now complete on filenames as well as
4870 program symbols. Thus, if you type "break foob TAB", and the source
4871 files linked into the programs include `foobar.c', that file name will
4872 be one of the candidates for completion. However, file names are not
4873 considered for completion after you typed a colon that delimits a file
4874 name from a name of a function in that file, as in "break foo.c:bar".
4876 `set demangle-style' completes on available demangling styles.
4878 * New platform-independent commands:
4880 It is now possible to define a post-hook for a command as well as a
4881 hook that runs before the command. For more details, see the
4882 documentation of `hookpost' in the GDB manual.
4884 * Changes in GNU/Linux native debugging.
4886 Support for debugging multi-threaded programs has been completely
4887 revised for all platforms except m68k and sparc. You can now debug as
4888 many threads as your system allows you to have.
4890 Attach/detach is supported for multi-threaded programs.
4892 Support for SSE registers was added for x86. This doesn't work for
4893 multi-threaded programs though.
4895 * Changes in MIPS configurations.
4897 Multi-arch support is enabled for all MIPS configurations.
4899 GDB can now be built as native debugger on SGI Irix 6.x systems for
4900 debugging n32 executables. (Debugging 64-bit executables is not yet
4903 * Unified support for hardware watchpoints in all x86 configurations.
4905 Most (if not all) native x86 configurations support hardware-assisted
4906 breakpoints and watchpoints in a unified manner. This support
4907 implements debug register sharing between watchpoints, which allows to
4908 put a virtually infinite number of watchpoints on the same address,
4909 and also supports watching regions up to 16 bytes with several debug
4912 The new maintenance command `maintenance show-debug-regs' toggles
4913 debugging print-outs in functions that insert, remove, and test
4914 watchpoints and hardware breakpoints.
4916 * Changes in the DJGPP native configuration.
4918 New command ``info dos sysinfo'' displays assorted information about
4919 the CPU, OS, memory, and DPMI server.
4921 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4922 display information about segment descriptors stored in GDT, LDT, and
4925 New commands ``info dos pde'' and ``info dos pte'' display entries
4926 from Page Directory and Page Tables (for now works with CWSDPMI only).
4927 New command ``info dos address-pte'' displays the Page Table entry for
4928 a given linear address.
4930 GDB can now pass command lines longer than 126 characters to the
4931 program being debugged (requires an update to the libdbg.a library
4932 which is part of the DJGPP development kit).
4934 DWARF2 debug info is now supported.
4936 It is now possible to `step' and `next' through calls to `longjmp'.
4938 * Changes in documentation.
4940 All GDB documentation was converted to GFDL, the GNU Free
4941 Documentation License.
4943 Tracepoints-related commands are now fully documented in the GDB
4946 TUI, the Text-mode User Interface, is now documented in the manual.
4948 Tracepoints-related commands are now fully documented in the GDB
4951 The "GDB Internals" manual now has an index. It also includes
4952 documentation of `ui_out' functions, GDB coding standards, x86
4953 hardware watchpoints, and memory region attributes.
4955 * GDB's version number moved to ``version.in''
4957 The Makefile variable VERSION has been replaced by the file
4958 ``version.in''. People creating GDB distributions should update the
4959 contents of this file.
4963 GUD support is now a standard part of the EMACS distribution.
4965 *** Changes in GDB 5.0:
4967 * Improved support for debugging FP programs on x86 targets
4969 Unified and much-improved support for debugging floating-point
4970 programs on all x86 targets. In particular, ``info float'' now
4971 displays the FP registers in the same format on all x86 targets, with
4972 greater level of detail.
4974 * Improvements and bugfixes in hardware-assisted watchpoints
4976 It is now possible to watch array elements, struct members, and
4977 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4978 on x86 targets no longer erroneously trigger when the address is
4981 * Improvements in the native DJGPP version of GDB
4983 The distribution now includes all the scripts and auxiliary files
4984 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4985 machines ``out of the box''.
4987 The DJGPP version can now debug programs that use signals. It is
4988 possible to catch signals that happened in the debuggee, deliver
4989 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4990 would kill the program being debugged.) Programs that hook hardware
4991 interrupts (keyboard, timer, etc.) can also be debugged.
4993 It is now possible to debug DJGPP programs that redirect their
4994 standard handles or switch them to raw (as opposed to cooked) mode, or
4995 even close them. The command ``run < foo > bar'' works as expected,
4996 and ``info terminal'' reports useful information about the debuggee's
4997 terminal, including raw/cooked mode, redirection, etc.
4999 The DJGPP version now uses termios functions for console I/O, which
5000 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5003 DOS-style file names with drive letters are now fully supported by
5006 It is now possible to debug DJGPP programs that switch their working
5007 directory. It is also possible to rerun the debuggee any number of
5008 times without restarting GDB; thus, you can use the same setup,
5009 breakpoints, etc. for many debugging sessions.
5011 * New native configurations
5013 ARM GNU/Linux arm*-*-linux*
5014 PowerPC GNU/Linux powerpc-*-linux*
5018 Motorola MCore mcore-*-*
5019 x86 VxWorks i[3456]86-*-vxworks*
5020 PowerPC VxWorks powerpc-*-vxworks*
5021 TI TMS320C80 tic80-*-*
5023 * OBSOLETE configurations
5025 Altos 3068 m68*-altos-*
5026 Convex c1-*-*, c2-*-*
5028 ARM RISCix arm-*-* (as host)
5031 Configurations that have been declared obsolete will be commented out,
5032 but the code will be left in place. If there is no activity to revive
5033 these configurations before the next release of GDB, the sources will
5034 be permanently REMOVED.
5036 * Gould support removed
5038 Support for the Gould PowerNode and NP1 has been removed.
5040 * New features for SVR4
5042 On SVR4 native platforms (such as Solaris), if you attach to a process
5043 without first loading a symbol file, GDB will now attempt to locate and
5044 load symbols from the running process's executable file.
5046 * Many C++ enhancements
5048 C++ support has been greatly improved. Overload resolution now works properly
5049 in almost all cases. RTTI support is on the way.
5051 * Remote targets can connect to a sub-program
5053 A popen(3) style serial-device has been added. This device starts a
5054 sub-process (such as a stand-alone simulator) and then communicates
5055 with that. The sub-program to run is specified using the syntax
5056 ``|<program> <args>'' vis:
5058 (gdb) set remotedebug 1
5059 (gdb) target extended-remote |mn10300-elf-sim program-args
5061 * MIPS 64 remote protocol
5063 A long standing bug in the mips64 remote protocol where by GDB
5064 expected certain 32 bit registers (ex SR) to be transfered as 32
5065 instead of 64 bits has been fixed.
5067 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5068 added to provide backward compatibility with older versions of GDB.
5070 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5072 The command ``set remotebinarydownload'' command has been replaced by
5073 ``set remote X-packet''. Other commands in ``set remote'' family
5074 include ``set remote P-packet''.
5076 * Breakpoint commands accept ranges.
5078 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5079 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5080 ``tracepoint passcount'' also accepts a range of tracepoints.
5082 * ``apropos'' command added.
5084 The ``apropos'' command searches through command names and
5085 documentation strings, printing out matches, making it much easier to
5086 try to find a command that does what you are looking for.
5090 A new machine oriented interface (MI) has been added to GDB. This
5091 interface is designed for debug environments running GDB as a separate
5092 process. This is part of the long term libGDB project. See the
5093 "GDB/MI" chapter of the GDB manual for further information. It can be
5094 enabled by configuring with:
5096 .../configure --enable-gdbmi
5098 *** Changes in GDB-4.18:
5100 * New native configurations
5102 HP-UX 10.20 hppa*-*-hpux10.20
5103 HP-UX 11.x hppa*-*-hpux11.0*
5104 M68K GNU/Linux m68*-*-linux*
5108 Fujitsu FR30 fr30-*-elf*
5109 Intel StrongARM strongarm-*-*
5110 Mitsubishi D30V d30v-*-*
5112 * OBSOLETE configurations
5114 Gould PowerNode, NP1 np1-*-*, pn-*-*
5116 Configurations that have been declared obsolete will be commented out,
5117 but the code will be left in place. If there is no activity to revive
5118 these configurations before the next release of GDB, the sources will
5119 be permanently REMOVED.
5123 As a compatibility experiment, GDB's source files buildsym.h and
5124 buildsym.c have been converted to pure standard C, no longer
5125 containing any K&R compatibility code. We believe that all systems in
5126 use today either come with a standard C compiler, or have a GCC port
5127 available. If this is not true, please report the affected
5128 configuration to bug-gdb@gnu.org immediately. See the README file for
5129 information about getting a standard C compiler if you don't have one
5134 GDB now uses readline 2.2.
5136 * set extension-language
5138 You can now control the mapping between filename extensions and source
5139 languages by using the `set extension-language' command. For instance,
5140 you can ask GDB to treat .c files as C++ by saying
5141 set extension-language .c c++
5142 The command `info extensions' lists all of the recognized extensions
5143 and their associated languages.
5145 * Setting processor type for PowerPC and RS/6000
5147 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5148 you can use the `set processor' command to specify what variant of the
5149 PowerPC family you are debugging. The command
5153 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5154 following PowerPC and RS6000 variants:
5156 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5157 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5159 403GC IBM PowerPC 403GC
5160 505 Motorola PowerPC 505
5161 860 Motorola PowerPC 860 or 850
5162 601 Motorola PowerPC 601
5163 602 Motorola PowerPC 602
5164 603 Motorola/IBM PowerPC 603 or 603e
5165 604 Motorola PowerPC 604 or 604e
5166 750 Motorola/IBM PowerPC 750 or 750
5168 At the moment, this command just tells GDB what to name the
5169 special-purpose processor registers. Since almost all the affected
5170 registers are inaccessible to user-level programs, this command is
5171 only useful for remote debugging in its present form.
5175 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5176 more extensive support for HP-UX. Added features include shared
5177 library support, kernel threads and hardware watchpoints for 11.00,
5178 support for HP's ANSI C and C++ compilers, and a compatibility mode
5179 for xdb and dbx commands.
5183 HP's donation includes the new concept of catchpoints, which is a
5184 generalization of the old catch command. On HP-UX, it is now possible
5185 to catch exec, fork, and vfork, as well as library loading.
5187 This means that the existing catch command has changed; its first
5188 argument now specifies the type of catch to be set up. See the
5189 output of "help catch" for a list of catchpoint types.
5191 * Debugging across forks
5193 On HP-UX, you can choose which process to debug when a fork() happens
5198 HP has donated a curses-based terminal user interface (TUI). To get
5199 it, build with --enable-tui. Although this can be enabled for any
5200 configuration, at present it only works for native HP debugging.
5202 * GDB remote protocol additions
5204 A new protocol packet 'X' that writes binary data is now available.
5205 Default behavior is to try 'X', then drop back to 'M' if the stub
5206 fails to respond. The settable variable `remotebinarydownload'
5207 allows explicit control over the use of 'X'.
5209 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5210 full 64-bit address. The command
5212 set remoteaddresssize 32
5214 can be used to revert to the old behaviour. For existing remote stubs
5215 the change should not be noticed, as the additional address information
5218 In order to assist in debugging stubs, you may use the maintenance
5219 command `packet' to send any text string to the stub. For instance,
5221 maint packet heythere
5223 sends the packet "$heythere#<checksum>". Note that it is very easy to
5224 disrupt a debugging session by sending the wrong packet at the wrong
5227 The compare-sections command allows you to compare section data on the
5228 target to what is in the executable file without uploading or
5229 downloading, by comparing CRC checksums.
5231 * Tracing can collect general expressions
5233 You may now collect general expressions at tracepoints. This requires
5234 further additions to the target-side stub; see tracepoint.c and
5235 doc/agentexpr.texi for further details.
5237 * mask-address variable for Mips
5239 For Mips targets, you may control the zeroing of the upper 32 bits of
5240 a 64-bit address by entering `set mask-address on'. This is mainly
5241 of interest to users of embedded R4xxx and R5xxx processors.
5243 * Higher serial baud rates
5245 GDB's serial code now allows you to specify baud rates 57600, 115200,
5246 230400, and 460800 baud. (Note that your host system may not be able
5247 to achieve all of these rates.)
5251 The i960 configuration now includes an initial implementation of a
5252 builtin simulator, contributed by Jim Wilson.
5255 *** Changes in GDB-4.17:
5257 * New native configurations
5259 Alpha GNU/Linux alpha*-*-linux*
5260 Unixware 2.x i[3456]86-unixware2*
5261 Irix 6.x mips*-sgi-irix6*
5262 PowerPC GNU/Linux powerpc-*-linux*
5263 PowerPC Solaris powerpcle-*-solaris*
5264 Sparc GNU/Linux sparc-*-linux*
5265 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5269 Argonaut Risc Chip (ARC) arc-*-*
5270 Hitachi H8/300S h8300*-*-*
5271 Matsushita MN10200 w/simulator mn10200-*-*
5272 Matsushita MN10300 w/simulator mn10300-*-*
5273 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5274 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5275 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5276 Mitsubishi D10V w/simulator d10v-*-*
5277 Mitsubishi M32R/D w/simulator m32r-*-elf*
5278 Tsqware Sparclet sparclet-*-*
5279 NEC V850 w/simulator v850-*-*
5281 * New debugging protocols
5283 ARM with RDI protocol arm*-*-*
5284 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5285 DDB and LSI variants of PMON protocol mips*-*-*
5286 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5287 PowerPC with SDS protocol powerpc{,le}-*-eabi
5288 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5292 All configurations can now understand and use the DWARF 2 debugging
5293 format. The choice is automatic, if the symbol file contains DWARF 2
5298 GDB now includes basic Java language support. This support is
5299 only useful with Java compilers that produce native machine code.
5301 * solib-absolute-prefix and solib-search-path
5303 For SunOS and SVR4 shared libraries, you may now set the prefix for
5304 loading absolute shared library symbol files, and the search path for
5305 locating non-absolute shared library symbol files.
5307 * Live range splitting
5309 GDB can now effectively debug code for which GCC has performed live
5310 range splitting as part of its optimization. See gdb/doc/LRS for
5311 more details on the expected format of the stabs information.
5315 GDB's support for the GNU Hurd, including thread debugging, has been
5316 updated to work with current versions of the Hurd.
5320 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5321 instruction set. ARM GDB automatically detects when Thumb
5322 instructions are in use, and adjusts disassembly and backtracing
5327 GDB's MIPS target configurations now handle the MIP16 16-bit
5332 GDB now includes support for overlays; if an executable has been
5333 linked such that multiple sections are based at the same address, GDB
5334 will decide which section to use for symbolic info. You can choose to
5335 control the decision manually, using overlay commands, or implement
5336 additional target-side support and use "overlay load-target" to bring
5337 in the overlay mapping. Do "help overlay" for more detail.
5341 The command "info symbol <address>" displays information about
5342 the symbol at the specified address.
5346 The standard remote protocol now includes an extension that allows
5347 asynchronous collection and display of trace data. This requires
5348 extensive support in the target-side debugging stub. Tracing mode
5349 includes a new interaction mode in GDB and new commands: see the
5350 file tracepoint.c for more details.
5354 Configurations for embedded MIPS now include a simulator contributed
5355 by Cygnus Solutions. The simulator supports the instruction sets
5356 of most MIPS variants.
5360 Sparc configurations may now include the ERC32 simulator contributed
5361 by the European Space Agency. The simulator is not built into
5362 Sparc targets by default; configure with --enable-sim to include it.
5366 For target configurations that may include multiple variants of a
5367 basic architecture (such as MIPS and SH), you may now set the
5368 architecture explicitly. "set arch" sets, "info arch" lists
5369 the possible architectures.
5371 *** Changes in GDB-4.16:
5373 * New native configurations
5375 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5376 M68K NetBSD m68k-*-netbsd*
5377 PowerPC AIX 4.x powerpc-*-aix*
5378 PowerPC MacOS powerpc-*-macos*
5379 PowerPC Windows NT powerpcle-*-cygwin32
5380 RS/6000 AIX 4.x rs6000-*-aix4*
5384 ARM with RDP protocol arm-*-*
5385 I960 with MON960 i960-*-coff
5386 MIPS VxWorks mips*-*-vxworks*
5387 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5388 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5390 Matra Sparclet sparclet-*-*
5394 The powerpc-eabi configuration now includes the PSIM simulator,
5395 contributed by Andrew Cagney, with assistance from Mike Meissner.
5396 PSIM is a very elaborate model of the PowerPC, including not only
5397 basic instruction set execution, but also details of execution unit
5398 performance and I/O hardware. See sim/ppc/README for more details.
5402 GDB now works with Solaris 2.5.
5404 * Windows 95/NT native
5406 GDB will now work as a native debugger on Windows 95 and Windows NT.
5407 To build it from source, you must use the "gnu-win32" environment,
5408 which uses a DLL to emulate enough of Unix to run the GNU tools.
5409 Further information, binaries, and sources are available at
5410 ftp.cygnus.com, under pub/gnu-win32.
5412 * dont-repeat command
5414 If a user-defined command includes the command `dont-repeat', then the
5415 command will not be repeated if the user just types return. This is
5416 useful if the command is time-consuming to run, so that accidental
5417 extra keystrokes don't run the same command many times.
5419 * Send break instead of ^C
5421 The standard remote protocol now includes an option to send a break
5422 rather than a ^C to the target in order to interrupt it. By default,
5423 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5425 * Remote protocol timeout
5427 The standard remote protocol includes a new variable `remotetimeout'
5428 that allows you to set the number of seconds before GDB gives up trying
5429 to read from the target. The default value is 2.
5431 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5433 By default GDB will automatically keep track of objects as they are
5434 loaded and unloaded by the dynamic linker. By using the command `set
5435 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5436 when shared library events occur, thus allowing you to set breakpoints
5437 in shared libraries which are explicitly loaded by the inferior.
5439 Note this feature does not work on hpux8. On hpux9 you must link
5440 /usr/lib/end.o into your program. This feature should work
5441 automatically on hpux10.
5443 * Irix 5.x hardware watchpoint support
5445 Irix 5 configurations now support the use of hardware watchpoints.
5447 * Mips protocol "SYN garbage limit"
5449 When debugging a Mips target using the `target mips' protocol, you
5450 may set the number of characters that GDB will ignore by setting
5451 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5452 every character. The default value is 1050.
5454 * Recording and replaying remote debug sessions
5456 If you set `remotelogfile' to the name of a file, gdb will write to it
5457 a recording of a remote debug session. This recording may then be
5458 replayed back to gdb using "gdbreplay". See gdbserver/README for
5459 details. This is useful when you have a problem with GDB while doing
5460 remote debugging; you can make a recording of the session and send it
5461 to someone else, who can then recreate the problem.
5463 * Speedups for remote debugging
5465 GDB includes speedups for downloading and stepping MIPS systems using
5466 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5467 and more efficient S-record downloading.
5469 * Memory use reductions and statistics collection
5471 GDB now uses less memory and reports statistics about memory usage.
5472 Try the `maint print statistics' command, for example.
5474 *** Changes in GDB-4.15:
5476 * Psymtabs for XCOFF
5478 The symbol reader for AIX GDB now uses partial symbol tables. This
5479 can greatly improve startup time, especially for large executables.
5481 * Remote targets use caching
5483 Remote targets now use a data cache to speed up communication with the
5484 remote side. The data cache could lead to incorrect results because
5485 it doesn't know about volatile variables, thus making it impossible to
5486 debug targets which use memory mapped I/O devices. `set remotecache
5487 off' turns the the data cache off.
5489 * Remote targets may have threads
5491 The standard remote protocol now includes support for multiple threads
5492 in the target system, using new protocol commands 'H' and 'T'. See
5493 gdb/remote.c for details.
5497 If GDB is configured with `--enable-netrom', then it will include
5498 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5499 acts as though it is a bank of ROM on the target board, but you can
5500 write into it over the network. GDB's support consists only of
5501 support for fast loading into the emulated ROM; to debug, you must use
5502 another protocol, such as standard remote protocol. The usual
5503 sequence is something like
5505 target nrom <netrom-hostname>
5507 target remote <netrom-hostname>:1235
5511 GDB now includes support for the Apple Macintosh, as a host only. It
5512 may be run as either an MPW tool or as a standalone application, and
5513 it can debug through the serial port. All the usual GDB commands are
5514 available, but to the target command, you must supply "serial" as the
5515 device type instead of "/dev/ttyXX". See mpw-README in the main
5516 directory for more information on how to build. The MPW configuration
5517 scripts */mpw-config.in support only a few targets, and only the
5518 mips-idt-ecoff target has been tested.
5522 GDB configuration now uses autoconf. This is not user-visible,
5523 but does simplify configuration and building.
5527 GDB now supports hpux10.
5529 *** Changes in GDB-4.14:
5531 * New native configurations
5533 x86 FreeBSD i[345]86-*-freebsd
5534 x86 NetBSD i[345]86-*-netbsd
5535 NS32k NetBSD ns32k-*-netbsd
5536 Sparc NetBSD sparc-*-netbsd
5540 A29K VxWorks a29k-*-vxworks
5541 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5542 CPU32 EST-300 emulator m68*-*-est*
5543 PowerPC ELF powerpc-*-elf
5546 * Alpha OSF/1 support for procfs
5548 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5549 possible to attach to running processes. As the mounting of the /proc
5550 filesystem is optional on the Alpha, GDB automatically determines
5551 the availability of /proc during startup. This can lead to problems
5552 if /proc is unmounted after GDB has been started.
5554 * Arguments to user-defined commands
5556 User commands may accept up to 10 arguments separated by whitespace.
5557 Arguments are accessed within the user command via $arg0..$arg9. A
5560 print $arg0 + $arg1 + $arg2
5562 To execute the command use:
5565 Defines the command "adder" which prints the sum of its three arguments.
5566 Note the arguments are text substitutions, so they may reference variables,
5567 use complex expressions, or even perform inferior function calls.
5569 * New `if' and `while' commands
5571 This makes it possible to write more sophisticated user-defined
5572 commands. Both commands take a single argument, which is the
5573 expression to evaluate, and must be followed by the commands to
5574 execute, one per line, if the expression is nonzero, the list being
5575 terminated by the word `end'. The `if' command list may include an
5576 `else' word, which causes the following commands to be executed only
5577 if the expression is zero.
5579 * Fortran source language mode
5581 GDB now includes partial support for Fortran 77. It will recognize
5582 Fortran programs and can evaluate a subset of Fortran expressions, but
5583 variables and functions may not be handled correctly. GDB will work
5584 with G77, but does not yet know much about symbols emitted by other
5587 * Better HPUX support
5589 Most debugging facilities now work on dynamic executables for HPPAs
5590 running hpux9 or later. You can attach to running dynamically linked
5591 processes, but by default the dynamic libraries will be read-only, so
5592 for instance you won't be able to put breakpoints in them. To change
5593 that behavior do the following before running the program:
5599 This will cause the libraries to be mapped private and read-write.
5600 To revert to the normal behavior, do this:
5606 You cannot set breakpoints or examine data in the library until after
5607 the library is loaded if the function/data symbols do not have
5610 GDB can now also read debug symbols produced by the HP C compiler on
5611 HPPAs (sorry, no C++, Fortran or 68k support).
5613 * Target byte order now dynamically selectable
5615 You can choose which byte order to use with a target system, via the
5616 commands "set endian big" and "set endian little", and you can see the
5617 current setting by using "show endian". You can also give the command
5618 "set endian auto", in which case GDB will use the byte order
5619 associated with the executable. Currently, only embedded MIPS
5620 configurations support dynamic selection of target byte order.
5622 * New DOS host serial code
5624 This version uses DPMI interrupts to handle buffered I/O, so you
5625 no longer need to run asynctsr when debugging boards connected to
5628 *** Changes in GDB-4.13:
5630 * New "complete" command
5632 This lists all the possible completions for the rest of the line, if it
5633 were to be given as a command itself. This is intended for use by emacs.
5635 * Trailing space optional in prompt
5637 "set prompt" no longer adds a space for you after the prompt you set. This
5638 allows you to set a prompt which ends in a space or one that does not.
5640 * Breakpoint hit counts
5642 "info break" now displays a count of the number of times the breakpoint
5643 has been hit. This is especially useful in conjunction with "ignore"; you
5644 can ignore a large number of breakpoint hits, look at the breakpoint info
5645 to see how many times the breakpoint was hit, then run again, ignoring one
5646 less than that number, and this will get you quickly to the last hit of
5649 * Ability to stop printing at NULL character
5651 "set print null-stop" will cause GDB to stop printing the characters of
5652 an array when the first NULL is encountered. This is useful when large
5653 arrays actually contain only short strings.
5655 * Shared library breakpoints
5657 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5658 breakpoints in shared libraries before the executable is run.
5660 * Hardware watchpoints
5662 There is a new hardware breakpoint for the watch command for sparclite
5663 targets. See gdb/sparclite/hw_breakpoint.note.
5665 Hardware watchpoints are also now supported under GNU/Linux.
5669 Annotations have been added. These are for use with graphical interfaces,
5670 and are still experimental. Currently only gdba.el uses these.
5672 * Improved Irix 5 support
5674 GDB now works properly with Irix 5.2.
5676 * Improved HPPA support
5678 GDB now works properly with the latest GCC and GAS.
5680 * New native configurations
5682 Sequent PTX4 i[34]86-sequent-ptx4
5683 HPPA running OSF/1 hppa*-*-osf*
5684 Atari TT running SVR4 m68*-*-sysv4*
5685 RS/6000 LynxOS rs6000-*-lynxos*
5689 OS/9000 i[34]86-*-os9k
5690 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5693 * Hitachi SH7000 and E7000-PC ICE support
5695 There is now support for communicating with the Hitachi E7000-PC ICE.
5696 This is available automatically when GDB is configured for the SH.
5700 As usual, a variety of small fixes and improvements, both generic
5701 and configuration-specific. See the ChangeLog for more detail.
5703 *** Changes in GDB-4.12:
5705 * Irix 5 is now supported
5709 GDB-4.12 on the HPPA has a number of changes which make it unable
5710 to debug the output from the currently released versions of GCC and
5711 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5712 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5713 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5716 *** Changes in GDB-4.11:
5718 * User visible changes:
5722 The "set remotedebug" option is now consistent between the mips remote
5723 target, remote targets using the gdb-specific protocol, UDI (AMD's
5724 debug protocol for the 29k) and the 88k bug monitor. It is now an
5725 integer specifying a debug level (normally 0 or 1, but 2 means more
5726 debugging info for the mips target).
5728 * DEC Alpha native support
5730 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5731 debug info, but GDB works fairly well with the DEC compiler and should
5732 work with a future GCC release. See the README file for a few
5733 Alpha-specific notes.
5735 * Preliminary thread implementation
5737 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5739 * LynxOS native and target support for 386
5741 This release has been hosted on LynxOS 2.2, and also can be configured
5742 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5745 * Improvements in C++ mangling/demangling.
5747 This release has much better g++ debugging, specifically in name
5748 mangling/demangling, virtual function calls, print virtual table,
5749 call methods, ...etc.
5751 *** Changes in GDB-4.10:
5753 * User visible changes:
5755 Remote debugging using the GDB-specific (`target remote') protocol now
5756 supports the `load' command. This is only useful if you have some
5757 other way of getting the stub to the target system, and you can put it
5758 somewhere in memory where it won't get clobbered by the download.
5760 Filename completion now works.
5762 When run under emacs mode, the "info line" command now causes the
5763 arrow to point to the line specified. Also, "info line" prints
5764 addresses in symbolic form (as well as hex).
5766 All vxworks based targets now support a user settable option, called
5767 vxworks-timeout. This option represents the number of seconds gdb
5768 should wait for responses to rpc's. You might want to use this if
5769 your vxworks target is, perhaps, a slow software simulator or happens
5770 to be on the far side of a thin network line.
5774 This release contains support for using a DEC alpha as a GDB host for
5775 cross debugging. Native alpha debugging is not supported yet.
5778 *** Changes in GDB-4.9:
5782 This is the first GDB release which is accompanied by a matching testsuite.
5783 The testsuite requires installation of dejagnu, which should be available
5784 via ftp from most sites that carry GNU software.
5788 'Cfront' style demangling has had its name changed to 'ARM' style, to
5789 emphasize that it was written from the specifications in the C++ Annotated
5790 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5791 disclaimers, it still generated too much confusion with users attempting to
5792 use gdb with AT&T cfront.
5796 GDB now uses a standard remote interface to a simulator library.
5797 So far, the library contains simulators for the Zilog Z8001/2, the
5798 Hitachi H8/300, H8/500 and Super-H.
5800 * New targets supported
5802 H8/300 simulator h8300-hitachi-hms or h8300hms
5803 H8/500 simulator h8500-hitachi-hms or h8500hms
5804 SH simulator sh-hitachi-hms or sh
5805 Z8000 simulator z8k-zilog-none or z8ksim
5806 IDT MIPS board over serial line mips-idt-ecoff
5808 Cross-debugging to GO32 targets is supported. It requires a custom
5809 version of the i386-stub.c module which is integrated with the
5810 GO32 memory extender.
5812 * New remote protocols
5814 MIPS remote debugging protocol.
5816 * New source languages supported
5818 This version includes preliminary support for Chill, a Pascal like language
5819 used by telecommunications companies. Chill support is also being integrated
5820 into the GNU compiler, but we don't know when it will be publically available.
5823 *** Changes in GDB-4.8:
5825 * HP Precision Architecture supported
5827 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5828 version of this support was available as a set of patches from the
5829 University of Utah. GDB does not support debugging of programs
5830 compiled with the HP compiler, because HP will not document their file
5831 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5832 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5834 Many problems in the preliminary version have been fixed.
5836 * Faster and better demangling
5838 We have improved template demangling and fixed numerous bugs in the GNU style
5839 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5840 character types (wchar_t) are now supported. Demangling of each symbol is now
5841 only done once, and is cached when the symbol table for a file is read in.
5842 This results in a small increase in memory usage for C programs, a moderate
5843 increase in memory usage for C++ programs, and a fantastic speedup in
5846 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5847 from the specifications in the Annotated Reference Manual, which AT&T's
5848 compiler does not actually implement.
5850 * G++ multiple inheritance compiler problem
5852 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5853 inheritance lattices was reworked to properly discover ambiguities. We
5854 recently found an example which causes this new algorithm to fail in a
5855 very subtle way, producing bad debug information for those classes.
5856 The file 'gcc.patch' (in this directory) can be applied to gcc to
5857 circumvent the problem. A future GCC release will contain a complete
5860 The previous G++ debug info problem (mentioned below for the gdb-4.7
5861 release) is fixed in gcc version 2.3.2.
5863 * Improved configure script
5865 The `configure' script will now attempt to guess your system type if
5866 you don't supply a host system type. The old scheme of supplying a
5867 host system triplet is preferable over using this. All the magic is
5868 done in the new `config.guess' script. Examine it for details.
5870 We have also brought our configure script much more in line with the FSF's
5871 version. It now supports the --with-xxx options. In particular,
5872 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5873 The resulting GDB will not be able to read arbitrary object file formats --
5874 only the format ``expected'' to be used on the configured target system.
5875 We hope to make this the default in a future release.
5877 * Documentation improvements
5879 There's new internal documentation on how to modify GDB, and how to
5880 produce clean changes to the code. We implore people to read it
5881 before submitting changes.
5883 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5884 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5885 `info' files are also provided. To build `info' files from scratch,
5886 you will need the latest `makeinfo' release, which will be available in
5887 a future texinfo-X.Y release.
5889 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5890 We're not sure exactly which versions have this problem, but it has
5891 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5892 or better. If that isn't possible, there is a patch in
5893 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5894 around this problem.
5898 GDB now supports array constants that can be used in expressions typed in by
5899 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5900 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5903 The new directory `gdb/sparclite' contains a program that demonstrates
5904 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5906 * New native hosts supported
5908 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5909 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5911 * New targets supported
5913 AMD 29k family via UDI a29k-amd-udi or udi29k
5915 * New file formats supported
5917 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5918 HPUX core files, and SCO 3.2v2 core files.
5922 Attaching to processes now works again; thanks for the many bug reports.
5924 We have also stomped on a bunch of core dumps caused by
5925 printf_filtered("%s") problems.
5927 We eliminated a copyright problem on the rpc and ptrace header files
5928 for VxWorks, which was discovered at the last minute during the 4.7
5929 release. You should now be able to build a VxWorks GDB.
5931 You can now interrupt gdb while an attached process is running. This
5932 will cause the attached process to stop, and give control back to GDB.
5934 We fixed problems caused by using too many file descriptors
5935 for reading symbols from object files and libraries. This was
5936 especially a problem for programs that used many (~100) shared
5939 The `step' command now only enters a subroutine if there is line number
5940 information for the subroutine. Otherwise it acts like the `next'
5941 command. Previously, `step' would enter subroutines if there was
5942 any debugging information about the routine. This avoids problems
5943 when using `cc -g1' on MIPS machines.
5945 * Internal improvements
5947 GDB's internal interfaces have been improved to make it easier to support
5948 debugging of multiple languages in the future.
5950 GDB now uses a common structure for symbol information internally.
5951 Minimal symbols (derived from linkage symbols in object files), partial
5952 symbols (from a quick scan of debug information), and full symbols
5953 contain a common subset of information, making it easier to write
5954 shared code that handles any of them.
5956 * New command line options
5958 We now accept --silent as an alias for --quiet.
5962 The memory-mapped-malloc library is now licensed under the GNU Library
5963 General Public License.
5965 *** Changes in GDB-4.7:
5967 * Host/native/target split
5969 GDB has had some major internal surgery to untangle the support for
5970 hosts and remote targets. Now, when you configure GDB for a remote
5971 target, it will no longer load in all of the support for debugging
5972 local programs on the host. When fully completed and tested, this will
5973 ensure that arbitrary host/target combinations are possible.
5975 The primary conceptual shift is to separate the non-portable code in
5976 GDB into three categories. Host specific code is required any time GDB
5977 is compiled on that host, regardless of the target. Target specific
5978 code relates to the peculiarities of the target, but can be compiled on
5979 any host. Native specific code is everything else: it can only be
5980 built when the host and target are the same system. Child process
5981 handling and core file support are two common `native' examples.
5983 GDB's use of /proc for controlling Unix child processes is now cleaner.
5984 It has been split out into a single module under the `target_ops' vector,
5985 plus two native-dependent functions for each system that uses /proc.
5987 * New hosts supported
5989 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5990 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5991 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5993 * New targets supported
5995 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5996 68030 and CPU32 m68030-*-*, m68332-*-*
5998 * New native hosts supported
6000 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6001 (386bsd is not well tested yet)
6002 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6004 * New file formats supported
6006 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6007 supports reading of `a.out.adobe' object files, which are an a.out
6008 format extended with minimal information about multiple sections.
6012 `show copying' is the same as the old `info copying'.
6013 `show warranty' is the same as `info warrantee'.
6014 These were renamed for consistency. The old commands continue to work.
6016 `info handle' is a new alias for `info signals'.
6018 You can now define pre-command hooks, which attach arbitrary command
6019 scripts to any command. The commands in the hook will be executed
6020 prior to the user's command. You can also create a hook which will be
6021 executed whenever the program stops. See gdb.texinfo.
6025 We now deal with Cfront style name mangling, and can even extract type
6026 info from mangled symbols. GDB can automatically figure out which
6027 symbol mangling style your C++ compiler uses.
6029 Calling of methods and virtual functions has been improved as well.
6033 The crash that occured when debugging Sun Ansi-C compiled binaries is
6034 fixed. This was due to mishandling of the extra N_SO stabs output
6037 We also finally got Ultrix 4.2 running in house, and fixed core file
6038 support, with help from a dozen people on the net.
6040 John M. Farrell discovered that the reason that single-stepping was so
6041 slow on all of the Mips based platforms (primarily SGI and DEC) was
6042 that we were trying to demangle and lookup a symbol used for internal
6043 purposes on every instruction that was being stepped through. Changing
6044 the name of that symbol so that it couldn't be mistaken for a C++
6045 mangled symbol sped things up a great deal.
6047 Rich Pixley sped up symbol lookups in general by getting much smarter
6048 about when C++ symbol mangling is necessary. This should make symbol
6049 completion (TAB on the command line) much faster. It's not as fast as
6050 we'd like, but it's significantly faster than gdb-4.6.
6054 A new user controllable variable 'call_scratch_address' can
6055 specify the location of a scratch area to be used when GDB
6056 calls a function in the target. This is necessary because the
6057 usual method of putting the scratch area on the stack does not work
6058 in systems that have separate instruction and data spaces.
6060 We integrated changes to support the 29k UDI (Universal Debugger
6061 Interface), but discovered at the last minute that we didn't have all
6062 of the appropriate copyright paperwork. We are working with AMD to
6063 resolve this, and hope to have it available soon.
6067 We have sped up the remote serial line protocol, especially for targets
6068 with lots of registers. It now supports a new `expedited status' ('T')
6069 message which can be used in place of the existing 'S' status message.
6070 This allows the remote stub to send only the registers that GDB
6071 needs to make a quick decision about single-stepping or conditional
6072 breakpoints, eliminating the need to fetch the entire register set for
6073 each instruction being stepped through.
6075 The GDB remote serial protocol now implements a write-through cache for
6076 registers, only re-reading the registers if the target has run.
6078 There is also a new remote serial stub for SPARC processors. You can
6079 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6080 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6081 processor with a serial port.
6085 Configure.in files have become much easier to read and modify. A new
6086 `table driven' format makes it more obvious what configurations are
6087 supported, and what files each one uses.
6091 There is a new opcodes library which will eventually contain all of the
6092 disassembly routines and opcode tables. At present, it only contains
6093 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6094 disassembler (binutils/objdump) to share these routines.
6096 The libiberty library is now copylefted under the GNU Library General
6097 Public License. This allows more liberal use, and was done so libg++
6098 can use it. This makes no difference to GDB, since the Library License
6099 grants all the rights from the General Public License.
6103 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6104 reference to the stabs symbol info used by the debugger. It is (as far
6105 as we know) the only published document on this fascinating topic. We
6106 encourage you to read it, compare it to the stabs information on your
6107 system, and send improvements on the document in general (to
6108 bug-gdb@prep.ai.mit.edu).
6110 And, of course, many bugs have been fixed.
6113 *** Changes in GDB-4.6:
6115 * Better support for C++ function names
6117 GDB now accepts as input the "demangled form" of C++ overloaded function
6118 names and member function names, and can do command completion on such names
6119 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6120 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6121 Make use of command completion, it is your friend.
6123 GDB also now accepts a variety of C++ mangled symbol formats. They are
6124 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6125 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6126 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6127 for the list of formats.
6129 * G++ symbol mangling problem
6131 Recent versions of gcc have a bug in how they emit debugging information for
6132 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6133 directory) can be applied to gcc to fix the problem. Alternatively, if you
6134 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6135 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6136 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6139 * New 'maintenance' command
6141 All of the commands related to hacking GDB internals have been moved out of
6142 the main command set, and now live behind the 'maintenance' command. This
6143 can also be abbreviated as 'mt'. The following changes were made:
6145 dump-me -> maintenance dump-me
6146 info all-breakpoints -> maintenance info breakpoints
6147 printmsyms -> maintenance print msyms
6148 printobjfiles -> maintenance print objfiles
6149 printpsyms -> maintenance print psymbols
6150 printsyms -> maintenance print symbols
6152 The following commands are new:
6154 maintenance demangle Call internal GDB demangler routine to
6155 demangle a C++ link name and prints the result.
6156 maintenance print type Print a type chain for a given symbol
6158 * Change to .gdbinit file processing
6160 We now read the $HOME/.gdbinit file before processing the argv arguments
6161 (e.g. reading symbol files or core files). This allows global parameters to
6162 be set, which will apply during the symbol reading. The ./.gdbinit is still
6163 read after argv processing.
6165 * New hosts supported
6167 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6169 GNU/Linux support i386-unknown-linux or linux
6171 We are also including code to support the HP/PA running BSD and HPUX. This
6172 is almost guaranteed not to work, as we didn't have time to test or build it
6173 for this release. We are including it so that the more adventurous (or
6174 masochistic) of you can play with it. We also had major problems with the
6175 fact that the compiler that we got from HP doesn't support the -g option.
6178 * New targets supported
6180 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6182 * More smarts about finding #include files
6184 GDB now remembers the compilation directory for all include files, and for
6185 all files from which C is generated (like yacc and lex sources). This
6186 greatly improves GDB's ability to find yacc/lex sources, and include files,
6187 especially if you are debugging your program from a directory different from
6188 the one that contains your sources.
6190 We also fixed a bug which caused difficulty with listing and setting
6191 breakpoints in include files which contain C code. (In the past, you had to
6192 try twice in order to list an include file that you hadn't looked at before.)
6194 * Interesting infernals change
6196 GDB now deals with arbitrary numbers of sections, where the symbols for each
6197 section must be relocated relative to that section's landing place in the
6198 target's address space. This work was needed to support ELF with embedded
6199 stabs used by Solaris-2.0.
6201 * Bug fixes (of course!)
6203 There have been loads of fixes for the following things:
6204 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6205 i960, stabs, DOS(GO32), procfs, etc...
6207 See the ChangeLog for details.
6209 *** Changes in GDB-4.5:
6211 * New machines supported (host and target)
6213 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6215 SGI Irix-4.x mips-sgi-irix4 or iris4
6217 * New malloc package
6219 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6220 Mmalloc is capable of handling mutiple heaps of memory. It is also
6221 capable of saving a heap to a file, and then mapping it back in later.
6222 This can be used to greatly speedup the startup of GDB by using a
6223 pre-parsed symbol table which lives in a mmalloc managed heap. For
6224 more details, please read mmalloc/mmalloc.texi.
6228 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6229 'help info proc' for details.
6231 * MIPS ecoff symbol table format
6233 The code that reads MIPS symbol table format is now supported on all hosts.
6234 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6237 * File name changes for MS-DOS
6239 Many files in the config directories have been renamed to make it easier to
6240 support GDB on MS-DOSe systems (which have very restrictive file name
6241 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6242 environment) is close to working but has some remaining problems. Note
6243 that debugging of DOS programs is not supported, due to limitations
6244 in the ``operating system'', but it can be used to host cross-debugging.
6246 * Cross byte order fixes
6248 Many fixes have been made to support cross debugging of Sparc and MIPS
6249 targets from hosts whose byte order differs.
6251 * New -mapped and -readnow options
6253 If memory-mapped files are available on your system through the 'mmap'
6254 system call, you can use the -mapped option on the `file' or
6255 `symbol-file' commands to cause GDB to write the symbols from your
6256 program into a reusable file. If the program you are debugging is
6257 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6258 Future GDB debugging sessions will notice the presence of this file,
6259 and will quickly map in symbol information from it, rather than reading
6260 the symbol table from the executable program. Using the '-mapped'
6261 option in a GDB `file' or `symbol-file' command has the same effect as
6262 starting GDB with the '-mapped' command-line option.
6264 You can cause GDB to read the entire symbol table immediately by using
6265 the '-readnow' option with any of the commands that load symbol table
6266 information (or on the GDB command line). This makes the command
6267 slower, but makes future operations faster.
6269 The -mapped and -readnow options are typically combined in order to
6270 build a `fred.syms' file that contains complete symbol information.
6271 A simple GDB invocation to do nothing but build a `.syms' file for future
6274 gdb -batch -nx -mapped -readnow programname
6276 The `.syms' file is specific to the host machine on which GDB is run.
6277 It holds an exact image of GDB's internal symbol table. It cannot be
6278 shared across multiple host platforms.
6280 * longjmp() handling
6282 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6283 siglongjmp() without losing control. This feature has not yet been ported to
6284 all systems. It currently works on many 386 platforms, all MIPS-based
6285 platforms (SGI, DECstation, etc), and Sun3/4.
6289 Preliminary work has been put in to support the new Solaris OS from Sun. At
6290 this time, it can control and debug processes, but it is not capable of
6295 As always, many many bug fixes. The major areas were with g++, and mipsread.
6296 People using the MIPS-based platforms should experience fewer mysterious
6297 crashes and trashed symbol tables.
6299 *** Changes in GDB-4.4:
6301 * New machines supported (host and target)
6303 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6305 BSD Reno on Vax vax-dec-bsd
6306 Ultrix on Vax vax-dec-ultrix
6308 * New machines supported (target)
6310 AMD 29000 embedded, using EBMON a29k-none-none
6314 GDB continues to improve its handling of C++. `References' work better.
6315 The demangler has also been improved, and now deals with symbols mangled as
6316 per the Annotated C++ Reference Guide.
6318 GDB also now handles `stabs' symbol information embedded in MIPS
6319 `ecoff' symbol tables. Since the ecoff format was not easily
6320 extensible to handle new languages such as C++, this appeared to be a
6321 good way to put C++ debugging info into MIPS binaries. This option
6322 will be supported in the GNU C compiler, version 2, when it is
6325 * New features for SVR4
6327 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6328 shared libraries. Debugging dynamically linked programs should present
6329 only minor differences from debugging statically linked programs.
6331 The `info proc' command will print out information about any process
6332 on an SVR4 system (including the one you are debugging). At the moment,
6333 it prints the address mappings of the process.
6335 If you bring up GDB on another SVR4 system, please send mail to
6336 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6338 * Better dynamic linking support in SunOS
6340 Reading symbols from shared libraries which contain debugging symbols
6341 now works properly. However, there remain issues such as automatic
6342 skipping of `transfer vector' code during function calls, which
6343 make it harder to debug code in a shared library, than to debug the
6344 same code linked statically.
6348 GDB is now using the latest `getopt' routines from the FSF. This
6349 version accepts the -- prefix for options with long names. GDB will
6350 continue to accept the old forms (-option and +option) as well.
6351 Various single letter abbreviations for options have been explicity
6352 added to the option table so that they won't get overshadowed in the
6353 future by other options that begin with the same letter.
6357 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6358 Many assorted bugs have been handled. Many more remain to be handled.
6359 See the various ChangeLog files (primarily in gdb and bfd) for details.
6362 *** Changes in GDB-4.3:
6364 * New machines supported (host and target)
6366 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6367 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6368 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6370 * Almost SCO Unix support
6372 We had hoped to support:
6373 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6374 (except for core file support), but we discovered very late in the release
6375 that it has problems with process groups that render gdb unusable. Sorry
6376 about that. I encourage people to fix it and post the fixes.
6378 * Preliminary ELF and DWARF support
6380 GDB can read ELF object files on System V Release 4, and can handle
6381 debugging records for C, in DWARF format, in ELF files. This support
6382 is preliminary. If you bring up GDB on another SVR4 system, please
6383 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6388 GDB now uses the latest `readline' library. One user-visible change
6389 is that two tabs will list possible command completions, which previously
6390 required typing M-? (meta-question mark, or ESC ?).
6394 The `stepi' bug that many of you noticed has been squashed.
6395 Many bugs in C++ have been handled. Many more remain to be handled.
6396 See the various ChangeLog files (primarily in gdb and bfd) for details.
6398 * State of the MIPS world (in case you wondered):
6400 GDB can understand the symbol tables emitted by the compilers
6401 supplied by most vendors of MIPS-based machines, including DEC. These
6402 symbol tables are in a format that essentially nobody else uses.
6404 Some versions of gcc come with an assembler post-processor called
6405 mips-tfile. This program is required if you want to do source-level
6406 debugging of gcc-compiled programs. I believe FSF does not ship
6407 mips-tfile with gcc version 1, but it will eventually come with gcc
6410 Debugging of g++ output remains a problem. g++ version 1.xx does not
6411 really support it at all. (If you're lucky, you should be able to get
6412 line numbers and stack traces to work, but no parameters or local
6413 variables.) With some work it should be possible to improve the
6416 When gcc version 2 is released, you will have somewhat better luck.
6417 However, even then you will get confusing results for inheritance and
6420 We will eventually provide full debugging of g++ output on
6421 DECstations. This will probably involve some kind of stabs-in-ecoff
6422 encapulation, but the details have not been worked out yet.
6425 *** Changes in GDB-4.2:
6427 * Improved configuration
6429 Only one copy of `configure' exists now, and it is not self-modifying.
6430 Porting BFD is simpler.
6434 The `step' and `next' commands now only stop at the first instruction
6435 of a source line. This prevents the multiple stops that used to occur
6436 in switch statements, for-loops, etc. `Step' continues to stop if a
6437 function that has debugging information is called within the line.
6441 Lots of small bugs fixed. More remain.
6443 * New host supported (not target)
6445 Intel 386 PC clone running Mach i386-none-mach
6448 *** Changes in GDB-4.1:
6450 * Multiple source language support
6452 GDB now has internal scaffolding to handle several source languages.
6453 It determines the type of each source file from its filename extension,
6454 and will switch expression parsing and number formatting to match the
6455 language of the function in the currently selected stack frame.
6456 You can also specifically set the language to be used, with
6457 `set language c' or `set language modula-2'.
6461 GDB now has preliminary support for the GNU Modula-2 compiler,
6462 currently under development at the State University of New York at
6463 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6464 continue through the fall of 1991 and into 1992.
6466 Other Modula-2 compilers are currently not supported, and attempting to
6467 debug programs compiled with them will likely result in an error as the
6468 symbol table is read. Feel free to work on it, though!
6470 There are hooks in GDB for strict type checking and range checking,
6471 in the `Modula-2 philosophy', but they do not currently work.
6475 GDB can now write to executable and core files (e.g. patch
6476 a variable's value). You must turn this switch on, specify
6477 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6478 by assigning a new value to a variable. Modifications take
6481 * Automatic SunOS shared library reading
6483 When you run your program, GDB automatically determines where its
6484 shared libraries (if any) have been loaded, and reads their symbols.
6485 The `share' command is no longer needed. This also works when
6486 examining core files.
6490 You can specify the number of lines that the `list' command shows.
6493 * New machines supported (host and target)
6495 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6496 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6497 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6499 * New hosts supported (not targets)
6501 IBM RT/PC: romp-ibm-aix or rtpc
6503 * New targets supported (not hosts)
6505 AMD 29000 embedded with COFF a29k-none-coff
6506 AMD 29000 embedded with a.out a29k-none-aout
6507 Ultracomputer remote kernel debug a29k-nyu-kern
6509 * New remote interfaces
6515 *** Changes in GDB-4.0:
6519 Wide output is wrapped at good places to make the output more readable.
6521 Gdb now supports cross-debugging from a host machine of one type to a
6522 target machine of another type. Communication with the target system
6523 is over serial lines. The ``target'' command handles connecting to the
6524 remote system; the ``load'' command will download a program into the
6525 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6526 also supports debugging of realtime processes running under VxWorks,
6527 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6528 stub on the target system.
6530 New CPUs supported include the AMD 29000 and Intel 960.
6532 GDB now reads object files and symbol tables via a ``binary file''
6533 library, which allows a single copy of GDB to debug programs of multiple
6534 object file types such as a.out and coff.
6536 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6537 refcard.dvi and refcard.ps are available to format it).
6540 * Control-Variable user interface simplified
6542 All variables that control the operation of the debugger can be set
6543 by the ``set'' command, and displayed by the ``show'' command.
6545 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6546 ``Show prompt'' produces the response:
6547 Gdb's prompt is new-gdb=>.
6549 What follows are the NEW set commands. The command ``help set'' will
6550 print a complete list of old and new set commands. ``help set FOO''
6551 will give a longer description of the variable FOO. ``show'' will show
6552 all of the variable descriptions and their current settings.
6554 confirm on/off: Enables warning questions for operations that are
6555 hard to recover from, e.g. rerunning the program while
6556 it is already running. Default is ON.
6558 editing on/off: Enables EMACS style command line editing
6559 of input. Previous lines can be recalled with
6560 control-P, the current line can be edited with control-B,
6561 you can search for commands with control-R, etc.
6564 history filename NAME: NAME is where the gdb command history
6565 will be stored. The default is .gdb_history,
6566 or the value of the environment variable
6569 history size N: The size, in commands, of the command history. The
6570 default is 256, or the value of the environment variable
6573 history save on/off: If this value is set to ON, the history file will
6574 be saved after exiting gdb. If set to OFF, the
6575 file will not be saved. The default is OFF.
6577 history expansion on/off: If this value is set to ON, then csh-like
6578 history expansion will be performed on
6579 command line input. The default is OFF.
6581 radix N: Sets the default radix for input and output. It can be set
6582 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6583 in the current radix, so "set radix 10" is always a no-op.
6585 height N: This integer value is the number of lines on a page. Default
6586 is 24, the current `stty rows'' setting, or the ``li#''
6587 setting from the termcap entry matching the environment
6590 width N: This integer value is the number of characters on a line.
6591 Default is 80, the current `stty cols'' setting, or the ``co#''
6592 setting from the termcap entry matching the environment
6595 Note: ``set screensize'' is obsolete. Use ``set height'' and
6596 ``set width'' instead.
6598 print address on/off: Print memory addresses in various command displays,
6599 such as stack traces and structure values. Gdb looks
6600 more ``symbolic'' if you turn this off; it looks more
6601 ``machine level'' with it on. Default is ON.
6603 print array on/off: Prettyprint arrays. New convenient format! Default
6606 print demangle on/off: Print C++ symbols in "source" form if on,
6609 print asm-demangle on/off: Same, for assembler level printouts
6612 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6615 * Support for Epoch Environment.
6617 The epoch environment is a version of Emacs v18 with windowing. One
6618 new command, ``inspect'', is identical to ``print'', except that if you
6619 are running in the epoch environment, the value is printed in its own
6623 * Support for Shared Libraries
6625 GDB can now debug programs and core files that use SunOS shared libraries.
6626 Symbols from a shared library cannot be referenced
6627 before the shared library has been linked with the program (this
6628 happens after you type ``run'' and before the function main() is entered).
6629 At any time after this linking (including when examining core files
6630 from dynamically linked programs), gdb reads the symbols from each
6631 shared library when you type the ``sharedlibrary'' command.
6632 It can be abbreviated ``share''.
6634 sharedlibrary REGEXP: Load shared object library symbols for files
6635 matching a unix regular expression. No argument
6636 indicates to load symbols for all shared libraries.
6638 info sharedlibrary: Status of loaded shared libraries.
6643 A watchpoint stops execution of a program whenever the value of an
6644 expression changes. Checking for this slows down execution
6645 tremendously whenever you are in the scope of the expression, but is
6646 quite useful for catching tough ``bit-spreader'' or pointer misuse
6647 problems. Some machines such as the 386 have hardware for doing this
6648 more quickly, and future versions of gdb will use this hardware.
6650 watch EXP: Set a watchpoint (breakpoint) for an expression.
6652 info watchpoints: Information about your watchpoints.
6654 delete N: Deletes watchpoint number N (same as breakpoints).
6655 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6656 enable N: Re-enables watchpoint number N (same as breakpoints).
6659 * C++ multiple inheritance
6661 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6664 * C++ exception handling
6666 Gdb now supports limited C++ exception handling. Besides the existing
6667 ability to breakpoint on an exception handler, gdb can breakpoint on
6668 the raising of an exception (before the stack is peeled back to the
6671 catch FOO: If there is a FOO exception handler in the dynamic scope,
6672 set a breakpoint to catch exceptions which may be raised there.
6673 Multiple exceptions (``catch foo bar baz'') may be caught.
6675 info catch: Lists all exceptions which may be caught in the
6676 current stack frame.
6679 * Minor command changes
6681 The command ``call func (arg, arg, ...)'' now acts like the print
6682 command, except it does not print or save a value if the function's result
6683 is void. This is similar to dbx usage.
6685 The ``up'' and ``down'' commands now always print the frame they end up
6686 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6687 frames without printing.
6689 * New directory command
6691 'dir' now adds directories to the FRONT of the source search path.
6692 The path starts off empty. Source files that contain debug information
6693 about the directory in which they were compiled can be found even
6694 with an empty path; Sun CC and GCC include this information. If GDB can't
6695 find your source file in the current directory, type "dir .".
6697 * Configuring GDB for compilation
6699 For normal use, type ``./configure host''. See README or gdb.texinfo
6702 GDB now handles cross debugging. If you are remotely debugging between
6703 two different machines, type ``./configure host -target=targ''.
6704 Host is the machine where GDB will run; targ is the machine
6705 where the program that you are debugging will run.