1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.0
6 * New features in the GDB remote stub, GDBserver
8 ** New "--selftest" command line option runs some GDBserver self
9 tests. These self tests are disabled in releases.
11 ** On Unix systems, GDBserver now does globbing expansion and variable
12 substitution in inferior command line arguments.
14 This is done by starting inferiors using a shell, like GDB does.
15 See "set startup-with-shell" in the user manual for how to disable
16 this from GDB when using "target extended-remote". When using
17 "target remote", you can disable the startup with shell by using the
18 new "--no-startup-with-shell" GDBserver command line option.
23 Indicates whether the inferior must be started with a shell or not.
25 * The "maintenance print c-tdesc" command now takes an optional
26 argument which is the file name of XML target description.
30 set debug separate-debug-file
31 show debug separate-debug-file
32 Control the display of debug output about separate debug file search.
34 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
37 *** Changes in GDB 8.0
39 * GDB now supports access to the PKU register on GNU/Linux. The register is
40 added by the Memory Protection Keys for Userspace feature which will be
41 available in future Intel CPUs.
43 * GDB now supports C++11 rvalue references.
47 ** New functions to start, stop and access a running btrace recording.
48 ** Rvalue references are now supported in gdb.Type.
50 * GDB now supports recording and replaying rdrand and rdseed Intel 64
53 * Building GDB and GDBserver now requires a C++11 compiler.
55 For example, GCC 4.8 or later.
57 It is no longer possible to build GDB or GDBserver with a C
58 compiler. The --disable-build-with-cxx configure option has been
61 * Building GDB and GDBserver now requires GNU make >= 3.81.
63 It is no longer supported to build GDB or GDBserver with another
64 implementation of the make program or an earlier version of GNU make.
66 * Native debugging on MS-Windows supports command-line redirection
68 Command-line arguments used for starting programs on MS-Windows can
69 now include redirection symbols supported by native Windows shells,
70 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
71 as "run", "start", and "set args", as well as the corresponding MI
74 * Support for thread names on MS-Windows.
76 GDB now catches and handles the special exception that programs
77 running on MS-Windows use to assign names to threads in the
80 * Support for Java programs compiled with gcj has been removed.
82 * User commands now accept an unlimited number of arguments.
83 Previously, only up to 10 was accepted.
85 * The "eval" command now expands user-defined command arguments.
87 This makes it easier to process a variable number of arguments:
92 eval "print $arg%d", $i
97 * Target descriptions can now describe registers for sparc32 and sparc64.
99 * GDB now supports DWARF version 5 (debug information format).
100 Its .debug_names index is not yet supported.
102 * New native configurations
104 FreeBSD/mips mips*-*-freebsd
108 Synopsys ARC arc*-*-elf32
109 FreeBSD/mips mips*-*-freebsd
111 * Removed targets and native configurations
113 Alpha running FreeBSD alpha*-*-freebsd*
114 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
119 Erases all the flash memory regions reported by the target.
121 maint print arc arc-instruction address
122 Print internal disassembler information about instruction at a given address.
126 set disassembler-options
127 show disassembler-options
128 Controls the passing of target specific information to the disassembler.
129 If it is necessary to specify more than one disassembler option then
130 multiple options can be placed together into a comma separated list.
131 The default value is the empty string. Currently, the only supported
132 targets are ARM, PowerPC and S/390.
137 Erases all the flash memory regions reported by the target. This is
138 equivalent to the CLI command flash-erase.
140 -file-list-shared-libraries
141 List the shared libraries in the program. This is
142 equivalent to the CLI command "info shared".
144 *** Changes in GDB 7.12
146 * GDB and GDBserver now build with a C++ compiler by default.
148 The --enable-build-with-cxx configure option is now enabled by
149 default. One must now explicitly configure with
150 --disable-build-with-cxx in order to build with a C compiler. This
151 option will be removed in a future release.
153 * GDBserver now supports recording btrace without maintaining an active
156 * GDB now supports a negative repeat count in the 'x' command to examine
157 memory backward from the given address. For example:
160 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
161 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
162 (gdb) x/-5i 0x0000000000400580
163 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
164 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
165 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
166 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
167 0x40057b <main(int, char**)+25>:
168 callq 0x400536 <Func1(int, char const*)>
170 * Fortran: Support structures with fields of dynamic types and
171 arrays of dynamic types.
173 * The symbol dumping maintenance commands have new syntax.
174 maint print symbols [-pc address] [--] [filename]
175 maint print symbols [-objfile objfile] [-source source] [--] [filename]
176 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
177 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
178 maint print msymbols [-objfile objfile] [--] [filename]
180 * GDB now supports multibit bitfields and enums in target register
183 * New Python-based convenience function $_as_string(val), which returns
184 the textual representation of a value. This function is especially
185 useful to obtain the text label of an enum value.
187 * Intel MPX bound violation handling.
189 Segmentation faults caused by a Intel MPX boundary violation
190 now display the kind of violation (upper or lower), the memory
191 address accessed and the memory bounds, along with the usual
192 signal received and code location.
196 Program received signal SIGSEGV, Segmentation fault
197 Upper bound violation while accessing address 0x7fffffffc3b3
198 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
199 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
201 * Rust language support.
202 GDB now supports debugging programs written in the Rust programming
203 language. See https://www.rust-lang.org/ for more information about
206 * Support for running interpreters on specified input/output devices
208 GDB now supports a new mechanism that allows frontends to provide
209 fully featured GDB console views, as a better alternative to
210 building such views on top of the "-interpreter-exec console"
211 command. See the new "new-ui" command below. With that command,
212 frontends can now start GDB in the traditional command-line mode
213 running in an embedded terminal emulator widget, and create a
214 separate MI interpreter running on a specified i/o device. In this
215 way, GDB handles line editing, history, tab completion, etc. in the
216 console all by itself, and the GUI uses the separate MI interpreter
217 for its own control and synchronization, invisible to the command
220 * The "catch syscall" command catches groups of related syscalls.
222 The "catch syscall" command now supports catching a group of related
223 syscalls using the 'group:' or 'g:' prefix.
228 skip -gfile file-glob-pattern
229 skip -function function
230 skip -rfunction regular-expression
231 A generalized form of the skip command, with new support for
232 glob-style file names and regular expressions for function names.
233 Additionally, a file spec and a function spec may now be combined.
235 maint info line-table REGEXP
236 Display the contents of GDB's internal line table data struture.
239 Run any GDB unit tests that were compiled in.
242 Start a new user interface instance running INTERP as interpreter,
243 using the TTY file for input/output.
247 ** gdb.Breakpoint objects have a new attribute "pending", which
248 indicates whether the breakpoint is pending.
249 ** Three new breakpoint-related events have been added:
250 gdb.breakpoint_created, gdb.breakpoint_modified, and
251 gdb.breakpoint_deleted.
254 Signal ("set") the given MS-Windows event object. This is used in
255 conjunction with the Windows JIT debugging (AeDebug) support, where
256 the OS suspends a crashing process until a debugger can attach to
257 it. Resuming the crashing process, in order to debug it, is done by
260 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
261 was added in GDBserver, including JIT compiling fast tracepoint's
262 conditional expression bytecode into native code.
264 * Support for various remote target protocols and ROM monitors has
267 target m32rsdi Remote M32R debugging over SDI
268 target mips MIPS remote debugging protocol
269 target pmon PMON ROM monitor
270 target ddb NEC's DDB variant of PMON for Vr4300
271 target rockhopper NEC RockHopper variant of PMON
272 target lsi LSI variant of PMO
274 * Support for tracepoints and fast tracepoints on powerpc-linux,
275 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
276 including JIT compiling fast tracepoint's conditional expression
277 bytecode into native code.
279 * MI async record =record-started now includes the method and format used for
280 recording. For example:
282 =record-started,thread-group="i1",method="btrace",format="bts"
284 * MI async record =thread-selected now includes the frame field. For example:
286 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
290 Andes NDS32 nds32*-*-elf
292 *** Changes in GDB 7.11
294 * GDB now supports debugging kernel-based threads on FreeBSD.
296 * Per-inferior thread numbers
298 Thread numbers are now per inferior instead of global. If you're
299 debugging multiple inferiors, GDB displays thread IDs using a
300 qualified INF_NUM.THR_NUM form. For example:
304 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
305 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
306 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
307 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
309 As consequence, thread numbers as visible in the $_thread
310 convenience variable and in Python's InferiorThread.num attribute
311 are no longer unique between inferiors.
313 GDB now maintains a second thread ID per thread, referred to as the
314 global thread ID, which is the new equivalent of thread numbers in
315 previous releases. See also $_gthread below.
317 For backwards compatibility, MI's thread IDs always refer to global
320 * Commands that accept thread IDs now accept the qualified
321 INF_NUM.THR_NUM form as well. For example:
324 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
327 * In commands that accept a list of thread IDs, you can now refer to
328 all threads of an inferior using a star wildcard. GDB accepts
329 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
330 refer to all threads of the current inferior. For example, "info
333 * You can use "info threads -gid" to display the global thread ID of
336 * The new convenience variable $_gthread holds the global number of
339 * The new convenience variable $_inferior holds the number of the
342 * GDB now displays the ID and name of the thread that hit a breakpoint
343 or received a signal, if your program is multi-threaded. For
346 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
347 Thread 1 "main" received signal SIGINT, Interrupt.
349 * Record btrace now supports non-stop mode.
351 * Support for tracepoints on aarch64-linux was added in GDBserver.
353 * The 'record instruction-history' command now indicates speculative execution
354 when using the Intel Processor Trace recording format.
356 * GDB now allows users to specify explicit locations, bypassing
357 the linespec parser. This feature is also available to GDB/MI
360 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
361 GDB now is able to debug both AArch64 applications and ARM applications
364 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
365 including JIT compiling fast tracepoint's conditional expression bytecode
368 * GDB now supports displaced stepping on AArch64 GNU/Linux.
370 * "info threads", "info inferiors", "info display", "info checkpoints"
371 and "maint info program-spaces" now list the corresponding items in
372 ascending ID order, for consistency with all other "info" commands.
374 * In Ada, the overloads selection menu has been enhanced to display the
375 parameter types and the return types for the matching overloaded subprograms.
379 maint set target-non-stop (on|off|auto)
380 maint show target-non-stop
381 Control whether GDB targets always operate in non-stop mode even if
382 "set non-stop" is "off". The default is "auto", meaning non-stop
383 mode is enabled if supported by the target.
385 maint set bfd-sharing
386 maint show bfd-sharing
387 Control the reuse of bfd objects.
391 Control display of debugging info regarding bfd caching.
395 Control display of debugging info regarding FreeBSD threads.
397 set remote multiprocess-extensions-packet
398 show remote multiprocess-extensions-packet
399 Set/show the use of the remote protocol multiprocess extensions.
401 set remote thread-events
402 show remote thread-events
403 Set/show the use of thread create/exit events.
405 set ada print-signatures on|off
406 show ada print-signatures"
407 Control whether parameter types and return types are displayed in overloads
408 selection menus. It is activaled (@code{on}) by default.
412 Controls the maximum size of memory, in bytes, that GDB will
413 allocate for value contents. Prevents incorrect programs from
414 causing GDB to allocate overly large buffers. Default is 64k.
416 * The "disassemble" command accepts a new modifier: /s.
417 It prints mixed source+disassembly like /m with two differences:
418 - disassembled instructions are now printed in program order, and
419 - and source for all relevant files is now printed.
420 The "/m" option is now considered deprecated: its "source-centric"
421 output hasn't proved useful in practice.
423 * The "record instruction-history" command accepts a new modifier: /s.
424 It behaves exactly like /m and prints mixed source+disassembly.
426 * The "set scheduler-locking" command supports a new mode "replay".
427 It behaves like "off" in record mode and like "on" in replay mode.
429 * Support for various ROM monitors has been removed:
431 target dbug dBUG ROM monitor for Motorola ColdFire
432 target picobug Motorola picobug monitor
433 target dink32 DINK32 ROM monitor for PowerPC
434 target m32r Renesas M32R/D ROM monitor
435 target mon2000 mon2000 ROM monitor
436 target ppcbug PPCBUG ROM monitor for PowerPC
438 * Support for reading/writing memory and extracting values on architectures
439 whose memory is addressable in units of any integral multiple of 8 bits.
444 Indicates whether the inferior must be started with a shell or not.
447 Indicates that an exec system call was executed.
449 exec-events feature in qSupported
450 The qSupported packet allows GDB to request support for exec
451 events using the new 'gdbfeature' exec-event, and the qSupported
452 response can contain the corresponding 'stubfeature'. Set and
453 show commands can be used to display whether these features are enabled.
456 Equivalent to interrupting with the ^C character, but works in
459 thread created stop reason (T05 create:...)
460 Indicates that the thread was just created and is stopped at entry.
462 thread exit stop reply (w exitcode;tid)
463 Indicates that the thread has terminated.
466 Enables/disables thread create and exit event reporting. For
467 example, this is used in non-stop mode when GDB stops a set of
468 threads and synchronously waits for the their corresponding stop
469 replies. Without exit events, if one of the threads exits, GDB
470 would hang forever not knowing that it should no longer expect a
471 stop for that same thread.
474 Indicates that there are no resumed threads left in the target (all
475 threads are stopped). The remote stub reports support for this stop
476 reply to GDB's qSupported query.
479 Enables/disables catching syscalls from the inferior process.
480 The remote stub reports support for this packet to GDB's qSupported query.
482 syscall_entry stop reason
483 Indicates that a syscall was just called.
485 syscall_return stop reason
486 Indicates that a syscall just returned.
488 * Extended-remote exec events
490 ** GDB now has support for exec events on extended-remote Linux targets.
491 For such targets with Linux kernels 2.5.46 and later, this enables
492 follow-exec-mode and exec catchpoints.
494 set remote exec-event-feature-packet
495 show remote exec-event-feature-packet
496 Set/show the use of the remote exec event feature.
498 * Thread names in remote protocol
500 The reply to qXfer:threads:read may now include a name attribute for each
503 * Target remote mode fork and exec events
505 ** GDB now has support for fork and exec events on target remote mode
506 Linux targets. For such targets with Linux kernels 2.5.46 and later,
507 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
508 fork and exec catchpoints.
510 * Remote syscall events
512 ** GDB now has support for catch syscall on remote Linux targets,
513 currently enabled on x86/x86_64 architectures.
515 set remote catch-syscall-packet
516 show remote catch-syscall-packet
517 Set/show the use of the remote catch syscall feature.
521 ** The -var-set-format command now accepts the zero-hexadecimal
522 format. It outputs data in hexadecimal format with zero-padding on the
527 ** gdb.InferiorThread objects have a new attribute "global_num",
528 which refers to the thread's global thread ID. The existing
529 "num" attribute now refers to the thread's per-inferior number.
530 See "Per-inferior thread numbers" above.
531 ** gdb.InferiorThread objects have a new attribute "inferior", which
532 is the Inferior object the thread belongs to.
534 *** Changes in GDB 7.10
536 * Support for process record-replay and reverse debugging on aarch64*-linux*
537 targets has been added. GDB now supports recording of A64 instruction set
538 including advance SIMD instructions.
540 * Support for Sun's version of the "stabs" debug file format has been removed.
542 * GDB now honors the content of the file /proc/PID/coredump_filter
543 (PID is the process ID) on GNU/Linux systems. This file can be used
544 to specify the types of memory mappings that will be included in a
545 corefile. For more information, please refer to the manual page of
546 "core(5)". GDB also has a new command: "set use-coredump-filter
547 on|off". It allows to set whether GDB will read the content of the
548 /proc/PID/coredump_filter file when generating a corefile.
550 * The "info os" command on GNU/Linux can now display information on
552 "info os cpus" Listing of all cpus/cores on the system
554 * GDB has two new commands: "set serial parity odd|even|none" and
555 "show serial parity". These allows to set or show parity for the
558 * The "info source" command now displays the producer string if it was
559 present in the debug info. This typically includes the compiler version
560 and may include things like its command line arguments.
562 * The "info dll", an alias of the "info sharedlibrary" command,
563 is now available on all platforms.
565 * Directory names supplied to the "set sysroot" commands may be
566 prefixed with "target:" to tell GDB to access shared libraries from
567 the target system, be it local or remote. This replaces the prefix
568 "remote:". The default sysroot has been changed from "" to
569 "target:". "remote:" is automatically converted to "target:" for
570 backward compatibility.
572 * The system root specified by "set sysroot" will be prepended to the
573 filename of the main executable (if reported to GDB as absolute by
574 the operating system) when starting processes remotely, and when
575 attaching to already-running local or remote processes.
577 * GDB now supports automatic location and retrieval of executable
578 files from remote targets. Remote debugging can now be initiated
579 using only a "target remote" or "target extended-remote" command
580 (no "set sysroot" or "file" commands are required). See "New remote
583 * The "dump" command now supports verilog hex format.
585 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
587 * On GNU/Linux, GDB and gdbserver are now able to access executable
588 and shared library files without a "set sysroot" command when
589 attaching to processes running in different mount namespaces from
590 the debugger. This makes it possible to attach to processes in
591 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
592 See "New remote packets" below.
594 * The "tui reg" command now provides completion for all of the
595 available register groups, including target specific groups.
597 * The HISTSIZE environment variable is no longer read when determining
598 the size of GDB's command history. GDB now instead reads the dedicated
599 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
600 disables truncation of command history. Non-numeric values of GDBHISTSIZE
605 ** Memory ports can now be unbuffered.
609 ** gdb.Objfile objects have a new attribute "username",
610 which is the name of the objfile as specified by the user,
611 without, for example, resolving symlinks.
612 ** You can now write frame unwinders in Python.
613 ** gdb.Type objects have a new method "optimized_out",
614 returning optimized out gdb.Value instance of this type.
615 ** gdb.Value objects have new methods "reference_value" and
616 "const_value" which return a reference to the value and a
617 "const" version of the value respectively.
621 maint print symbol-cache
622 Print the contents of the symbol cache.
624 maint print symbol-cache-statistics
625 Print statistics of symbol cache usage.
627 maint flush-symbol-cache
628 Flush the contents of the symbol cache.
632 Start branch trace recording using Branch Trace Store (BTS) format.
635 Evaluate expression by using the compiler and print result.
639 Explicit commands for enabling and disabling tui mode.
642 set mpx bound on i386 and amd64
643 Support for bound table investigation on Intel MPX enabled applications.
647 Start branch trace recording using Intel Processor Trace format.
650 Print information about branch tracing internals.
652 maint btrace packet-history
653 Print the raw branch tracing data.
655 maint btrace clear-packet-history
656 Discard the stored raw branch tracing data.
659 Discard all branch tracing data. It will be fetched and processed
660 anew by the next "record" command.
665 Renamed from "set debug dwarf2-die".
667 Renamed from "show debug dwarf2-die".
670 Renamed from "set debug dwarf2-read".
671 show debug dwarf-read
672 Renamed from "show debug dwarf2-read".
674 maint set dwarf always-disassemble
675 Renamed from "maint set dwarf2 always-disassemble".
676 maint show dwarf always-disassemble
677 Renamed from "maint show dwarf2 always-disassemble".
679 maint set dwarf max-cache-age
680 Renamed from "maint set dwarf2 max-cache-age".
681 maint show dwarf max-cache-age
682 Renamed from "maint show dwarf2 max-cache-age".
685 show debug dwarf-line
686 Control display of debugging info regarding DWARF line processing.
690 Set the maximum number of candidates to be considered during
691 completion. The default value is 200. This limit allows GDB
692 to avoid generating large completion lists, the computation of
693 which can cause the debugger to become temporarily unresponsive.
695 set history remove-duplicates
696 show history remove-duplicates
697 Control the removal of duplicate history entries.
699 maint set symbol-cache-size
700 maint show symbol-cache-size
701 Control the size of the symbol cache.
703 set|show record btrace bts buffer-size
704 Set and show the size of the ring buffer used for branch tracing in
706 The obtained size may differ from the requested size. Use "info
707 record" to see the obtained buffer size.
709 set debug linux-namespaces
710 show debug linux-namespaces
711 Control display of debugging info regarding Linux namespaces.
713 set|show record btrace pt buffer-size
714 Set and show the size of the ring buffer used for branch tracing in
715 Intel Processor Trace format.
716 The obtained size may differ from the requested size. Use "info
717 record" to see the obtained buffer size.
719 maint set|show btrace pt skip-pad
720 Set and show whether PAD packets are skipped when computing the
723 * The command 'thread apply all' can now support new option '-ascending'
724 to call its specified command for all threads in ascending order.
726 * Python/Guile scripting
728 ** GDB now supports auto-loading of Python/Guile scripts contained in the
729 special section named `.debug_gdb_scripts'.
733 qXfer:btrace-conf:read
734 Return the branch trace configuration for the current thread.
736 Qbtrace-conf:bts:size
737 Set the requested ring buffer size for branch tracing in BTS format.
740 Enable Intel Procesor Trace-based branch tracing for the current
741 process. The remote stub reports support for this packet to GDB's
745 Set the requested ring buffer size for branch tracing in Intel Processor
749 Indicates a memory breakpoint instruction was executed, irrespective
750 of whether it was GDB that planted the breakpoint or the breakpoint
751 is hardcoded in the program. This is required for correct non-stop
755 Indicates the target stopped for a hardware breakpoint. This is
756 required for correct non-stop mode operation.
759 Return information about files on the remote system.
762 Return the full absolute name of the file that was executed to
763 create a process running on the remote system.
766 Select the filesystem on which vFile: operations with filename
767 arguments will operate. This is required for GDB to be able to
768 access files on remote targets where the remote stub does not
769 share a common filesystem with the inferior(s).
772 Indicates that a fork system call was executed.
775 Indicates that a vfork system call was executed.
777 vforkdone stop reason
778 Indicates that a vfork child of the specified process has executed
779 an exec or exit, allowing the vfork parent to resume execution.
781 fork-events and vfork-events features in qSupported
782 The qSupported packet allows GDB to request support for fork and
783 vfork events using new 'gdbfeatures' fork-events and vfork-events,
784 and the qSupported response can contain the corresponding
785 'stubfeatures'. Set and show commands can be used to display
786 whether these features are enabled.
788 * Extended-remote fork events
790 ** GDB now has support for fork events on extended-remote Linux
791 targets. For targets with Linux kernels 2.5.60 and later, this
792 enables follow-fork-mode and detach-on-fork for both fork and
793 vfork, as well as fork and vfork catchpoints.
795 * The info record command now shows the recording format and the
796 branch tracing configuration for the current thread when using
797 the btrace record target.
798 For the BTS format, it shows the ring buffer size.
800 * GDB now has support for DTrace USDT (Userland Static Defined
801 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
803 * GDB now supports access to vector registers on S/390 GNU/Linux
806 * Removed command line options
808 -xdb HP-UX XDB compatibility mode.
810 * Removed targets and native configurations
812 HP/PA running HP-UX hppa*-*-hpux*
813 Itanium running HP-UX ia64-*-hpux*
815 * New configure options
818 This configure option allows the user to build GDB with support for
819 Intel Processor Trace (default: auto). This requires libipt.
821 --with-libipt-prefix=PATH
822 Specify the path to the version of libipt that GDB should use.
823 $PATH/include should contain the intel-pt.h header and
824 $PATH/lib should contain the libipt.so library.
826 *** Changes in GDB 7.9.1
830 ** Xmethods can now specify a result type.
832 *** Changes in GDB 7.9
834 * GDB now supports hardware watchpoints on x86 GNU Hurd.
838 ** You can now access frame registers from Python scripts.
839 ** New attribute 'producer' for gdb.Symtab objects.
840 ** gdb.Objfile objects have a new attribute "progspace",
841 which is the gdb.Progspace object of the containing program space.
842 ** gdb.Objfile objects have a new attribute "owner".
843 ** gdb.Objfile objects have a new attribute "build_id",
844 which is the build ID generated when the file was built.
845 ** gdb.Objfile objects have a new method "add_separate_debug_file".
846 ** A new event "gdb.clear_objfiles" has been added, triggered when
847 selecting a new file to debug.
848 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
849 ** New function gdb.lookup_objfile.
851 New events which are triggered when GDB modifies the state of the
854 ** gdb.events.inferior_call_pre: Function call is about to be made.
855 ** gdb.events.inferior_call_post: Function call has just been made.
856 ** gdb.events.memory_changed: A memory location has been altered.
857 ** gdb.events.register_changed: A register has been altered.
859 * New Python-based convenience functions:
861 ** $_caller_is(name [, number_of_frames])
862 ** $_caller_matches(regexp [, number_of_frames])
863 ** $_any_caller_is(name [, number_of_frames])
864 ** $_any_caller_matches(regexp [, number_of_frames])
866 * GDB now supports the compilation and injection of source code into
867 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
868 to compile the source code to object code, and if successful, inject
869 and execute that code within the current context of the inferior.
870 Currently the C language is supported. The commands used to
871 interface with this new feature are:
873 compile code [-raw|-r] [--] [source code]
874 compile file [-raw|-r] filename
878 demangle [-l language] [--] name
879 Demangle "name" in the specified language, or the current language
880 if elided. This command is renamed from the "maint demangle" command.
881 The latter is kept as a no-op to avoid "maint demangle" being interpreted
882 as "maint demangler-warning".
884 queue-signal signal-name-or-number
885 Queue a signal to be delivered to the thread when it is resumed.
887 add-auto-load-scripts-directory directory
888 Add entries to the list of directories from which to load auto-loaded
891 maint print user-registers
892 List all currently available "user" registers.
894 compile code [-r|-raw] [--] [source code]
895 Compile, inject, and execute in the inferior the executable object
896 code produced by compiling the provided source code.
898 compile file [-r|-raw] filename
899 Compile and inject into the inferior the executable object code
900 produced by compiling the source code stored in the filename
903 * On resume, GDB now always passes the signal the program had stopped
904 for to the thread the signal was sent to, even if the user changed
905 threads before resuming. Previously GDB would often (but not
906 always) deliver the signal to the thread that happens to be current
909 * Conversely, the "signal" command now consistently delivers the
910 requested signal to the current thread. GDB now asks for
911 confirmation if the program had stopped for a signal and the user
912 switched threads meanwhile.
914 * "breakpoint always-inserted" modes "off" and "auto" merged.
916 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
917 won't remove breakpoints from the target until all threads stop,
918 even in non-stop mode. The "auto" mode has been removed, and "off"
919 is now the default mode.
923 set debug symbol-lookup
924 show debug symbol-lookup
925 Control display of debugging info regarding symbol lookup.
929 ** The -list-thread-groups command outputs an exit-code field for
930 inferiors that have exited.
934 MIPS SDE mips*-sde*-elf*
938 Support for these obsolete configurations has been removed.
940 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
941 SGI Irix-5.x mips-*-irix5*
942 SGI Irix-6.x mips-*-irix6*
943 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
944 VAX running Ultrix vax-*-ultrix*
946 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
947 and "assf"), have been removed. Use the "sharedlibrary" command, or
948 its alias "share", instead.
950 *** Changes in GDB 7.8
952 * New command line options
955 This is an alias for the --data-directory option.
957 * GDB supports printing and modifying of variable length automatic arrays
958 as specified in ISO C99.
960 * The ARM simulator now supports instruction level tracing
961 with or without disassembly.
965 GDB now has support for scripting using Guile. Whether this is
966 available is determined at configure time.
967 Guile version 2.0 or greater is required.
968 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
970 * New commands (for set/show, see "New options" below)
974 Invoke CODE by passing it to the Guile interpreter.
978 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
980 info auto-load guile-scripts [regexp]
981 Print the list of automatically loaded Guile scripts.
983 * The source command is now capable of sourcing Guile scripts.
984 This feature is dependent on the debugger being built with Guile support.
988 set print symbol-loading (off|brief|full)
989 show print symbol-loading
990 Control whether to print informational messages when loading symbol
991 information for a file. The default is "full", but when debugging
992 programs with large numbers of shared libraries the amount of output
995 set guile print-stack (none|message|full)
996 show guile print-stack
997 Show a stack trace when an error is encountered in a Guile script.
999 set auto-load guile-scripts (on|off)
1000 show auto-load guile-scripts
1001 Control auto-loading of Guile script files.
1003 maint ada set ignore-descriptive-types (on|off)
1004 maint ada show ignore-descriptive-types
1005 Control whether the debugger should ignore descriptive types in Ada
1006 programs. The default is not to ignore the descriptive types. See
1007 the user manual for more details on descriptive types and the intended
1008 usage of this option.
1010 set auto-connect-native-target
1012 Control whether GDB is allowed to automatically connect to the
1013 native target for the run, attach, etc. commands when not connected
1014 to any target yet. See also "target native" below.
1016 set record btrace replay-memory-access (read-only|read-write)
1017 show record btrace replay-memory-access
1018 Control what memory accesses are allowed during replay.
1020 maint set target-async (on|off)
1021 maint show target-async
1022 This controls whether GDB targets operate in synchronous or
1023 asynchronous mode. Normally the default is asynchronous, if it is
1024 available; but this can be changed to more easily debug problems
1025 occurring only in synchronous mode.
1027 set mi-async (on|off)
1029 Control whether MI asynchronous mode is preferred. This supersedes
1030 "set target-async" of previous GDB versions.
1032 * "set target-async" is deprecated as a CLI option and is now an alias
1033 for "set mi-async" (only puts MI into async mode).
1035 * Background execution commands (e.g., "c&", "s&", etc.) are now
1036 possible ``out of the box'' if the target supports them. Previously
1037 the user would need to explicitly enable the possibility with the
1038 "set target-async on" command.
1040 * New features in the GDB remote stub, GDBserver
1042 ** New option --debug-format=option1[,option2,...] allows one to add
1043 additional text to each output. At present only timestamps
1044 are supported: --debug-format=timestamps.
1045 Timestamps can also be turned on with the
1046 "monitor set debug-format timestamps" command from GDB.
1048 * The 'record instruction-history' command now starts counting instructions
1049 at one. This also affects the instruction ranges reported by the
1050 'record function-call-history' command when given the /i modifier.
1052 * The command 'record function-call-history' supports a new modifier '/c' to
1053 indent the function names based on their call stack depth.
1054 The fields for the '/i' and '/l' modifier have been reordered.
1055 The source line range is now prefixed with 'at'.
1056 The instruction range is now prefixed with 'inst'.
1057 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1058 "record instruction-history" and "list" commands.
1060 * The ranges given as arguments to the 'record function-call-history' and
1061 'record instruction-history' commands are now inclusive.
1063 * The btrace record target now supports the 'record goto' command.
1064 For locations inside the execution trace, the back trace is computed
1065 based on the information stored in the execution trace.
1067 * The btrace record target supports limited reverse execution and replay.
1068 The target does not record data and therefore does not allow reading
1069 memory or registers.
1071 * The "catch syscall" command now works on s390*-linux* targets.
1073 * The "compare-sections" command is no longer specific to target
1074 remote. It now works with all targets.
1076 * All native targets are now consistently called "native".
1077 Consequently, the "target child", "target GNU", "target djgpp",
1078 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1079 commands have been replaced with "target native". The QNX/NTO port
1080 leaves the "procfs" target in place and adds a "native" target for
1081 consistency with other ports. The impact on users should be minimal
1082 as these commands previously either throwed an error, or were
1083 no-ops. The target's name is visible in the output of the following
1084 commands: "help target", "info target", "info files", "maint print
1087 * The "target native" command now connects to the native target. This
1088 can be used to launch native programs even when "set
1089 auto-connect-native-target" is set to off.
1091 * GDB now supports access to Intel MPX registers on GNU/Linux.
1093 * Support for Intel AVX-512 registers on GNU/Linux.
1094 Support displaying and modifying Intel AVX-512 registers
1095 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1097 * New remote packets
1099 qXfer:btrace:read's annex
1100 The qXfer:btrace:read packet supports a new annex 'delta' to read
1101 branch trace incrementally.
1105 ** Valid Python operations on gdb.Value objects representing
1106 structs/classes invoke the corresponding overloaded operators if
1108 ** New `Xmethods' feature in the Python API. Xmethods are
1109 additional methods or replacements for existing methods of a C++
1110 class. This feature is useful for those cases where a method
1111 defined in C++ source code could be inlined or optimized out by
1112 the compiler, making it unavailable to GDB.
1115 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1117 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1118 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1119 its alias "share", instead.
1121 * The commands "set remotebaud" and "show remotebaud" are no longer
1122 supported. Use "set serial baud" and "show serial baud" (respectively)
1127 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1128 target-async". The latter is left as a deprecated alias of the
1129 former for backward compatibility. If the target supports it,
1130 CLI background execution commands are now always possible by
1131 default, independently of whether the frontend stated a
1132 preference for asynchronous execution with "-gdb-set mi-async".
1133 Previously "-gdb-set target-async off" affected both MI execution
1134 commands and CLI execution commands.
1136 *** Changes in GDB 7.7
1138 * Improved support for process record-replay and reverse debugging on
1139 arm*-linux* targets. Support for thumb32 and syscall instruction
1140 recording has been added.
1142 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1144 * GDB now supports Fission DWP file format version 2.
1145 http://gcc.gnu.org/wiki/DebugFission
1147 * New convenience function "$_isvoid", to check whether an expression
1148 is void. A void expression is an expression where the type of the
1149 result is "void". For example, some convenience variables may be
1150 "void" when evaluated (e.g., "$_exitcode" before the execution of
1151 the program being debugged; or an undefined convenience variable).
1152 Another example, when calling a function whose return type is
1155 * The "maintenance print objfiles" command now takes an optional regexp.
1157 * The "catch syscall" command now works on arm*-linux* targets.
1159 * GDB now consistently shows "<not saved>" when printing values of
1160 registers the debug info indicates have not been saved in the frame
1161 and there's nowhere to retrieve them from
1162 (callee-saved/call-clobbered registers):
1167 (gdb) info registers rax
1170 Before, the former would print "<optimized out>", and the latter
1171 "*value not available*".
1173 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1178 ** Frame filters and frame decorators have been added.
1179 ** Temporary breakpoints are now supported.
1180 ** Line tables representation has been added.
1181 ** New attribute 'parent_type' for gdb.Field objects.
1182 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1183 ** New attribute 'name' for gdb.Type objects.
1187 Nios II ELF nios2*-*-elf
1188 Nios II GNU/Linux nios2*-*-linux
1189 Texas Instruments MSP430 msp430*-*-elf
1191 * Removed native configurations
1193 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1194 been removed. ELF variants of these configurations are kept supported.
1196 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1197 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1198 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1199 i[34567]86-*-openbsd3.[0-3]
1200 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1201 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1202 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1206 Like "catch throw", but catches a re-thrown exception.
1207 maint check-psymtabs
1208 Renamed from old "maint check-symtabs".
1210 Perform consistency checks on symtabs.
1211 maint expand-symtabs
1212 Expand symtabs matching an optional regexp.
1215 Display the details of GDB configure-time options.
1217 maint set|show per-command
1218 maint set|show per-command space
1219 maint set|show per-command time
1220 maint set|show per-command symtab
1221 Enable display of per-command gdb resource usage.
1223 remove-symbol-file FILENAME
1224 remove-symbol-file -a ADDRESS
1225 Remove a symbol file added via add-symbol-file. The file to remove
1226 can be identified by its filename or by an address that lies within
1227 the boundaries of this symbol file in memory.
1230 info exceptions REGEXP
1231 Display the list of Ada exceptions defined in the program being
1232 debugged. If provided, only the exceptions whose names match REGEXP
1237 set debug symfile off|on
1239 Control display of debugging info regarding reading symbol files and
1240 symbol tables within those files
1242 set print raw frame-arguments
1243 show print raw frame-arguments
1244 Set/show whether to print frame arguments in raw mode,
1245 disregarding any defined pretty-printers.
1247 set remote trace-status-packet
1248 show remote trace-status-packet
1249 Set/show the use of remote protocol qTStatus packet.
1253 Control display of debugging messages related to Nios II targets.
1257 Control whether target-assisted range stepping is enabled.
1259 set startup-with-shell
1260 show startup-with-shell
1261 Specifies whether Unix child processes are started via a shell or
1266 Use the target memory cache for accesses to the code segment. This
1267 improves performance of remote debugging (particularly disassembly).
1269 * You can now use a literal value 'unlimited' for options that
1270 interpret 0 or -1 as meaning "unlimited". E.g., "set
1271 trace-buffer-size unlimited" is now an alias for "set
1272 trace-buffer-size -1" and "set height unlimited" is now an alias for
1275 * The "set debug symtab-create" debugging option of GDB has been changed to
1276 accept a verbosity level. 0 means "off", 1 provides basic debugging
1277 output, and values of 2 or greater provides more verbose output.
1279 * New command-line options
1281 Display the details of GDB configure-time options.
1283 * The command 'tsave' can now support new option '-ctf' to save trace
1284 buffer in Common Trace Format.
1286 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1289 * GDB now implements the the C++ 'typeid' operator.
1291 * The new convenience variable $_exception holds the exception being
1292 thrown or caught at an exception-related catchpoint.
1294 * The exception-related catchpoints, like "catch throw", now accept a
1295 regular expression which can be used to filter exceptions by type.
1297 * The new convenience variable $_exitsignal is automatically set to
1298 the terminating signal number when the program being debugged dies
1299 due to an uncaught signal.
1303 ** All MI commands now accept an optional "--language" option.
1304 Support for this feature can be verified by using the "-list-features"
1305 command, which should contain "language-option".
1307 ** The new command -info-gdb-mi-command allows the user to determine
1308 whether a GDB/MI command is supported or not.
1310 ** The "^error" result record returned when trying to execute an undefined
1311 GDB/MI command now provides a variable named "code" whose content is the
1312 "undefined-command" error code. Support for this feature can be verified
1313 by using the "-list-features" command, which should contain
1314 "undefined-command-error-code".
1316 ** The -trace-save MI command can optionally save trace buffer in Common
1319 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1321 ** The command -data-list-register-values now accepts an optional
1322 "--skip-unavailable" option. When used, only the available registers
1325 ** The new command -trace-frame-collected dumps collected variables,
1326 computed expressions, tvars, memory and registers in a traceframe.
1328 ** The commands -stack-list-locals, -stack-list-arguments and
1329 -stack-list-variables now accept an option "--skip-unavailable".
1330 When used, only the available locals or arguments are displayed.
1332 ** The -exec-run command now accepts an optional "--start" option.
1333 When used, the command follows the same semantics as the "start"
1334 command, stopping the program's execution at the start of its
1335 main subprogram. Support for this feature can be verified using
1336 the "-list-features" command, which should contain
1337 "exec-run-start-option".
1339 ** The new commands -catch-assert and -catch-exceptions insert
1340 catchpoints stopping the program when Ada exceptions are raised.
1342 ** The new command -info-ada-exceptions provides the equivalent of
1343 the new "info exceptions" command.
1345 * New system-wide configuration scripts
1346 A GDB installation now provides scripts suitable for use as system-wide
1347 configuration scripts for the following systems:
1351 * GDB now supports target-assigned range stepping with remote targets.
1352 This improves the performance of stepping source lines by reducing
1353 the number of control packets from/to GDB. See "New remote packets"
1356 * GDB now understands the element 'tvar' in the XML traceframe info.
1357 It has the id of the collected trace state variables.
1359 * On S/390 targets that provide the transactional-execution feature,
1360 the program interruption transaction diagnostic block (TDB) is now
1361 represented as a number of additional "registers" in GDB.
1363 * New remote packets
1367 The vCont packet supports a new 'r' action, that tells the remote
1368 stub to step through an address range itself, without GDB
1369 involvemement at each single-step.
1371 qXfer:libraries-svr4:read's annex
1372 The previously unused annex of the qXfer:libraries-svr4:read packet
1373 is now used to support passing an argument list. The remote stub
1374 reports support for this argument list to GDB's qSupported query.
1375 The defined arguments are "start" and "prev", used to reduce work
1376 necessary for library list updating, resulting in significant
1379 * New features in the GDB remote stub, GDBserver
1381 ** GDBserver now supports target-assisted range stepping. Currently
1382 enabled on x86/x86_64 GNU/Linux targets.
1384 ** GDBserver now adds element 'tvar' in the XML in the reply to
1385 'qXfer:traceframe-info:read'. It has the id of the collected
1386 trace state variables.
1388 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1391 * New 'z' formatter for printing and examining memory, this displays the
1392 value as hexadecimal zero padded on the left to the size of the type.
1394 * GDB can now use Windows x64 unwinding data.
1396 * The "set remotebaud" command has been replaced by "set serial baud".
1397 Similarly, "show remotebaud" has been replaced by "show serial baud".
1398 The "set remotebaud" and "show remotebaud" commands are still available
1399 to provide backward compatibility with older versions of GDB.
1401 *** Changes in GDB 7.6
1403 * Target record has been renamed to record-full.
1404 Record/replay is now enabled with the "record full" command.
1405 This also affects settings that are associated with full record/replay
1406 that have been moved from "set/show record" to "set/show record full":
1408 set|show record full insn-number-max
1409 set|show record full stop-at-limit
1410 set|show record full memory-query
1412 * A new record target "record-btrace" has been added. The new target
1413 uses hardware support to record the control-flow of a process. It
1414 does not support replaying the execution, but it implements the
1415 below new commands for investigating the recorded execution log.
1416 This new recording method can be enabled using:
1420 The "record-btrace" target is only available on Intel Atom processors
1421 and requires a Linux kernel 2.6.32 or later.
1423 * Two new commands have been added for record/replay to give information
1424 about the recorded execution without having to replay the execution.
1425 The commands are only supported by "record btrace".
1427 record instruction-history prints the execution history at
1428 instruction granularity
1430 record function-call-history prints the execution history at
1431 function granularity
1433 * New native configurations
1435 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1436 FreeBSD/powerpc powerpc*-*-freebsd
1437 x86_64/Cygwin x86_64-*-cygwin*
1438 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1442 ARM AArch64 aarch64*-*-elf
1443 ARM AArch64 GNU/Linux aarch64*-*-linux
1444 Lynx 178 PowerPC powerpc-*-lynx*178
1445 x86_64/Cygwin x86_64-*-cygwin*
1446 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1448 * If the configured location of system.gdbinit file (as given by the
1449 --with-system-gdbinit option at configure time) is in the
1450 data-directory (as specified by --with-gdb-datadir at configure
1451 time) or in one of its subdirectories, then GDB will look for the
1452 system-wide init file in the directory specified by the
1453 --data-directory command-line option.
1455 * New command line options:
1457 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1458 other initialization files, unlike -nx which disables all of them.
1460 * Removed command line options
1462 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1465 * The 'ptype' and 'whatis' commands now accept an argument to control
1468 * 'info proc' now works on some core files.
1472 ** Vectors can be created with gdb.Type.vector.
1474 ** Python's atexit.register now works in GDB.
1476 ** Types can be pretty-printed via a Python API.
1478 ** Python 3 is now supported (in addition to Python 2.4 or later)
1480 ** New class gdb.Architecture exposes GDB's internal representation
1481 of architecture in the Python API.
1483 ** New method Frame.architecture returns the gdb.Architecture object
1484 corresponding to the frame's architecture.
1486 * New Python-based convenience functions:
1488 ** $_memeq(buf1, buf2, length)
1489 ** $_streq(str1, str2)
1491 ** $_regex(str, regex)
1493 * The 'cd' command now defaults to using '~' (the home directory) if not
1496 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1497 default for GCC since November 2000.
1499 * The command 'forward-search' can now be abbreviated as 'fo'.
1501 * The command 'info tracepoints' can now display 'installed on target'
1502 or 'not installed on target' for each non-pending location of tracepoint.
1504 * New configure options
1506 --enable-libmcheck/--disable-libmcheck
1507 By default, development versions are built with -lmcheck on hosts
1508 that support it, in order to help track memory corruption issues.
1509 Release versions, on the other hand, are built without -lmcheck
1510 by default. The --enable-libmcheck/--disable-libmcheck configure
1511 options allow the user to override that default.
1512 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1513 This configure option allows the user to build GDB with
1514 libbabeltrace using which GDB can read Common Trace Format data.
1516 * New commands (for set/show, see "New options" below)
1519 Catch signals. This is similar to "handle", but allows commands and
1520 conditions to be attached.
1523 List the BFDs known to GDB.
1525 python-interactive [command]
1527 Start a Python interactive prompt, or evaluate the optional command
1528 and print the result of expressions.
1531 "py" is a new alias for "python".
1533 enable type-printer [name]...
1534 disable type-printer [name]...
1535 Enable or disable type printers.
1539 ** For the Renesas Super-H architecture, the "regs" command has been removed
1540 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1545 set print type methods (on|off)
1546 show print type methods
1547 Control whether method declarations are displayed by "ptype".
1548 The default is to show them.
1550 set print type typedefs (on|off)
1551 show print type typedefs
1552 Control whether typedef definitions are displayed by "ptype".
1553 The default is to show them.
1555 set filename-display basename|relative|absolute
1556 show filename-display
1557 Control the way in which filenames is displayed.
1558 The default is "relative", which preserves previous behavior.
1560 set trace-buffer-size
1561 show trace-buffer-size
1562 Request target to change the size of trace buffer.
1564 set remote trace-buffer-size-packet auto|on|off
1565 show remote trace-buffer-size-packet
1566 Control the use of the remote protocol `QTBuffer:size' packet.
1570 Control display of debugging messages related to ARM AArch64.
1573 set debug coff-pe-read
1574 show debug coff-pe-read
1575 Control display of debugging messages related to reading of COFF/PE
1580 Control display of debugging messages related to Mach-O symbols
1583 set debug notification
1584 show debug notification
1585 Control display of debugging info for async remote notification.
1589 ** Command parameter changes are now notified using new async record
1590 "=cmd-param-changed".
1591 ** Trace frame changes caused by command "tfind" are now notified using
1592 new async record "=traceframe-changed".
1593 ** The creation, deletion and modification of trace state variables
1594 are now notified using new async records "=tsv-created",
1595 "=tsv-deleted" and "=tsv-modified".
1596 ** The start and stop of process record are now notified using new
1597 async record "=record-started" and "=record-stopped".
1598 ** Memory changes are now notified using new async record
1600 ** The data-disassemble command response will include a "fullname" field
1601 containing the absolute file name when source has been requested.
1602 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1603 command, to allow pattern filling of memory areas.
1604 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1605 library load/unload events.
1606 ** The response to breakpoint commands and breakpoint async records
1607 includes an "installed" field containing a boolean state about each
1608 non-pending tracepoint location is whether installed on target or not.
1609 ** Output of the "-trace-status" command includes a "trace-file" field
1610 containing the name of the trace file being examined. This field is
1611 optional, and only present when examining a trace file.
1612 ** The "fullname" field is now always present along with the "file" field,
1613 even if the file cannot be found by GDB.
1615 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1616 You must have the LZMA library available when configuring GDB for this
1617 feature to be enabled. For more information, see:
1618 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1620 * New remote packets
1623 Set the size of trace buffer. The remote stub reports support for this
1624 packet to gdb's qSupported query.
1627 Enable Branch Trace Store (BTS)-based branch tracing for the current
1628 thread. The remote stub reports support for this packet to gdb's
1632 Disable branch tracing for the current thread. The remote stub reports
1633 support for this packet to gdb's qSupported query.
1636 Read the traced branches for the current thread. The remote stub
1637 reports support for this packet to gdb's qSupported query.
1639 *** Changes in GDB 7.5
1641 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1642 for more x32 ABI info.
1644 * GDB now supports access to MIPS DSP registers on Linux targets.
1646 * GDB now supports debugging microMIPS binaries.
1648 * The "info os" command on GNU/Linux can now display information on
1649 several new classes of objects managed by the operating system:
1650 "info os procgroups" lists process groups
1651 "info os files" lists file descriptors
1652 "info os sockets" lists internet-domain sockets
1653 "info os shm" lists shared-memory regions
1654 "info os semaphores" lists semaphores
1655 "info os msg" lists message queues
1656 "info os modules" lists loaded kernel modules
1658 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1659 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1660 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1661 options and inspect the probe arguments using the new $_probe_arg family
1662 of convenience variables. You can obtain more information about SystemTap
1663 in <http://sourceware.org/systemtap/>.
1665 * GDB now supports reversible debugging on ARM, it allows you to
1666 debug basic ARM and THUMB instructions, and provides
1667 record/replay support.
1669 * The option "symbol-reloading" has been deleted as it is no longer used.
1673 ** GDB commands implemented in Python can now be put in command class
1676 ** The "maint set python print-stack on|off" is now deleted.
1678 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1679 apply "flag enum"-style pretty-printing to any enum.
1681 ** gdb.lookup_symbol can now work when there is no current frame.
1683 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1684 the source at which the symbol was defined.
1686 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1687 method 'value'. The former indicates whether the symbol needs a
1688 frame in order to compute its value, and the latter computes the
1691 ** A new method 'referenced_value' on gdb.Value objects which can
1692 dereference pointer as well as C++ reference values.
1694 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1695 which return the global and static blocks (as gdb.Block objects),
1696 of the underlying symbol table, respectively.
1698 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1699 object associated with a PC value.
1701 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1702 of the address range occupied by code for the current source line.
1704 * Go language support.
1705 GDB now supports debugging programs written in the Go programming
1708 * GDBserver now supports stdio connections.
1709 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1711 * The binary "gdbtui" can no longer be built or installed.
1712 Use "gdb -tui" instead.
1714 * GDB will now print "flag" enums specially. A flag enum is one where
1715 all the enumerator values have no bits in common when pairwise
1716 "and"ed. When printing a value whose type is a flag enum, GDB will
1717 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1718 (gdb) print (enum E) 3
1721 * The filename part of a linespec will now match trailing components
1722 of a source file name. For example, "break gcc/expr.c:1000" will
1723 now set a breakpoint in build/gcc/expr.c, but not
1724 build/libcpp/expr.c.
1726 * The "info proc" and "generate-core-file" commands will now also
1727 work on remote targets connected to GDBserver on Linux.
1729 * The command "info catch" has been removed. It has been disabled
1730 since December 2007.
1732 * The "catch exception" and "catch assert" commands now accept
1733 a condition at the end of the command, much like the "break"
1734 command does. For instance:
1736 (gdb) catch exception Constraint_Error if Barrier = True
1738 Previously, it was possible to add a condition to such catchpoints,
1739 but it had to be done as a second step, after the catchpoint had been
1740 created, using the "condition" command.
1742 * The "info static-tracepoint-marker" command will now also work on
1743 native Linux targets with in-process agent.
1745 * GDB can now set breakpoints on inlined functions.
1747 * The .gdb_index section has been updated to include symbols for
1748 inlined functions. GDB will ignore older .gdb_index sections by
1749 default, which could cause symbol files to be loaded more slowly
1750 until their .gdb_index sections can be recreated. The new command
1751 "set use-deprecated-index-sections on" will cause GDB to use any older
1752 .gdb_index sections it finds. This will restore performance, but the
1753 ability to set breakpoints on inlined functions will be lost in symbol
1754 files with older .gdb_index sections.
1756 The .gdb_index section has also been updated to record more information
1757 about each symbol. This speeds up the "info variables", "info functions"
1758 and "info types" commands when used with programs having the .gdb_index
1759 section, as well as speeding up debugging with shared libraries using
1760 the .gdb_index section.
1762 * Ada support for GDB/MI Variable Objects has been added.
1764 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1769 ** New command -info-os is the MI equivalent of "info os".
1771 ** Output logs ("set logging" and related) now include MI output.
1775 ** "set use-deprecated-index-sections on|off"
1776 "show use-deprecated-index-sections on|off"
1777 Controls the use of deprecated .gdb_index sections.
1779 ** "catch load" and "catch unload" can be used to stop when a shared
1780 library is loaded or unloaded, respectively.
1782 ** "enable count" can be used to auto-disable a breakpoint after
1785 ** "info vtbl" can be used to show the virtual method tables for
1786 C++ and Java objects.
1788 ** "explore" and its sub commands "explore value" and "explore type"
1789 can be used to recursively explore values and types of
1790 expressions. These commands are available only if GDB is
1791 configured with '--with-python'.
1793 ** "info auto-load" shows status of all kinds of auto-loaded files,
1794 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1795 sequences of commands files, "info auto-load python-scripts"
1796 shows status of auto-loading Python script files,
1797 "info auto-load local-gdbinit" shows status of loading init file
1798 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1799 status of inferior specific thread debugging shared library loading.
1801 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1802 and "show auto-load-scripts" commands have been deprecated, use their
1803 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1804 and "show auto-load python-scripts" counterparts instead.
1806 ** "dprintf location,format,args..." creates a dynamic printf, which
1807 is basically a breakpoint that does a printf and immediately
1808 resumes your program's execution, so it is like a printf that you
1809 can insert dynamically at runtime instead of at compiletime.
1811 ** "set print symbol"
1813 Controls whether GDB attempts to display the symbol, if any,
1814 corresponding to addresses it prints. This defaults to "on", but
1815 you can set it to "off" to restore GDB's previous behavior.
1817 * Deprecated commands
1819 ** For the Renesas Super-H architecture, the "regs" command has been
1820 deprecated, and "info all-registers" should be used instead.
1824 Renesas RL78 rl78-*-elf
1825 HP OpenVMS ia64 ia64-hp-openvms*
1827 * GDBserver supports evaluation of breakpoint conditions. When
1828 support is advertised by GDBserver, GDB may be told to send the
1829 breakpoint conditions in bytecode form to GDBserver. GDBserver
1830 will only report the breakpoint trigger to GDB when its condition
1835 set mips compression
1836 show mips compression
1837 Select the compressed ISA encoding used in functions that have no symbol
1838 information available. The encoding can be set to either of:
1841 and is updated automatically from ELF file flags if available.
1843 set breakpoint condition-evaluation
1844 show breakpoint condition-evaluation
1845 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1846 GDBserver ("target"). Default option "auto" chooses the most efficient
1848 This option can improve debugger efficiency depending on the speed of the
1852 Disable auto-loading globally.
1855 Show auto-loading setting of all kinds of auto-loaded files.
1857 set auto-load gdb-scripts on|off
1858 show auto-load gdb-scripts
1859 Control auto-loading of GDB canned sequences of commands files.
1861 set auto-load python-scripts on|off
1862 show auto-load python-scripts
1863 Control auto-loading of Python script files.
1865 set auto-load local-gdbinit on|off
1866 show auto-load local-gdbinit
1867 Control loading of init file (.gdbinit) from current directory.
1869 set auto-load libthread-db on|off
1870 show auto-load libthread-db
1871 Control auto-loading of inferior specific thread debugging shared library.
1873 set auto-load scripts-directory <dir1>[:<dir2>...]
1874 show auto-load scripts-directory
1875 Set a list of directories from which to load auto-loaded scripts.
1876 Automatically loaded Python scripts and GDB scripts are located in one
1877 of the directories listed by this option.
1878 The delimiter (':' above) may differ according to the host platform.
1880 set auto-load safe-path <dir1>[:<dir2>...]
1881 show auto-load safe-path
1882 Set a list of directories from which it is safe to auto-load files.
1883 The delimiter (':' above) may differ according to the host platform.
1885 set debug auto-load on|off
1886 show debug auto-load
1887 Control display of debugging info for auto-loading the files above.
1889 set dprintf-style gdb|call|agent
1891 Control the way in which a dynamic printf is performed; "gdb"
1892 requests a GDB printf command, while "call" causes dprintf to call a
1893 function in the inferior. "agent" requests that the target agent
1894 (such as GDBserver) do the printing.
1896 set dprintf-function <expr>
1897 show dprintf-function
1898 set dprintf-channel <expr>
1899 show dprintf-channel
1900 Set the function and optional first argument to the call when using
1901 the "call" style of dynamic printf.
1903 set disconnected-dprintf on|off
1904 show disconnected-dprintf
1905 Control whether agent-style dynamic printfs continue to be in effect
1906 after GDB disconnects.
1908 * New configure options
1910 --with-auto-load-dir
1911 Configure default value for the 'set auto-load scripts-directory'
1912 setting above. It defaults to '$debugdir:$datadir/auto-load',
1913 $debugdir representing global debugging info directories (available
1914 via 'show debug-file-directory') and $datadir representing GDB's data
1915 directory (available via 'show data-directory').
1917 --with-auto-load-safe-path
1918 Configure default value for the 'set auto-load safe-path' setting
1919 above. It defaults to the --with-auto-load-dir setting.
1921 --without-auto-load-safe-path
1922 Set 'set auto-load safe-path' to '/', effectively disabling this
1925 * New remote packets
1927 z0/z1 conditional breakpoints extension
1929 The z0/z1 breakpoint insertion packets have been extended to carry
1930 a list of conditional expressions over to the remote stub depending on the
1931 condition evaluation mode. The use of this extension can be controlled
1932 via the "set remote conditional-breakpoints-packet" command.
1936 Specify the signals which the remote stub may pass to the debugged
1937 program without GDB involvement.
1939 * New command line options
1941 --init-command=FILE, -ix Like --command, -x but execute it
1942 before loading inferior.
1943 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1944 execute it before loading inferior.
1946 *** Changes in GDB 7.4
1948 * GDB now handles ambiguous linespecs more consistently; the existing
1949 FILE:LINE support has been expanded to other types of linespecs. A
1950 breakpoint will now be set on all matching locations in all
1951 inferiors, and locations will be added or removed according to
1954 * GDB now allows you to skip uninteresting functions and files when
1955 stepping with the "skip function" and "skip file" commands.
1957 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1958 and "show remote hardware-watchpoint-length-limit". These allows to
1959 set or show the maximum length limit (in bytes) of a remote
1960 target hardware watchpoint.
1962 This allows e.g. to use "unlimited" hardware watchpoints with the
1963 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1964 watchpoints are slower than real hardware watchpoints but are
1965 significantly faster than gdb software watchpoints.
1969 ** The register_pretty_printer function in module gdb.printing now takes
1970 an optional `replace' argument. If True, the new printer replaces any
1973 ** The "maint set python print-stack on|off" command has been
1974 deprecated and will be deleted in GDB 7.5.
1975 A new command: "set python print-stack none|full|message" has
1976 replaced it. Additionally, the default for "print-stack" is
1977 now "message", which just prints the error message without
1980 ** A prompt substitution hook (prompt_hook) is now available to the
1983 ** A new Python module, gdb.prompt has been added to the GDB Python
1984 modules library. This module provides functionality for
1985 escape sequences in prompts (used by set/show
1986 extended-prompt). These escape sequences are replaced by their
1987 corresponding value.
1989 ** Python commands and convenience-functions located in
1990 'data-directory'/python/gdb/command and
1991 'data-directory'/python/gdb/function are now automatically loaded
1994 ** Blocks now provide four new attributes. global_block and
1995 static_block will return the global and static blocks
1996 respectively. is_static and is_global are boolean attributes
1997 that indicate if the block is one of those two types.
1999 ** Symbols now provide the "type" attribute, the type of the symbol.
2001 ** The "gdb.breakpoint" function has been deprecated in favor of
2004 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2005 of a function. This class is based on the "finish" command
2006 available in the CLI.
2008 ** Type objects for struct and union types now allow access to
2009 the fields using standard Python dictionary (mapping) methods.
2010 For example, "some_type['myfield']" now works, as does
2011 "some_type.items()".
2013 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2016 ** A new function, "deep_items" has been added to the gdb.types
2017 module in the GDB Python modules library. This function returns
2018 an iterator over the fields of a struct or union type. Unlike
2019 the standard Python "iteritems" method, it will recursively traverse
2020 any anonymous fields.
2024 ** "*stopped" events can report several new "reason"s, such as
2027 ** Breakpoint changes are now notified using new async records, like
2028 "=breakpoint-modified".
2030 ** New command -ada-task-info.
2032 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2033 $sdir specifies the default system locations of shared libraries.
2034 $pdir specifies the directory where the libpthread used by the application
2037 GDB no longer looks in $sdir and $pdir after it has searched the directories
2038 mentioned in libthread-db-search-path. If you want to search those
2039 directories, they must be specified in libthread-db-search-path.
2040 The default value of libthread-db-search-path on GNU/Linux and Solaris
2041 systems is now "$sdir:$pdir".
2043 $pdir is not supported by gdbserver, it is currently ignored.
2044 $sdir is supported by gdbserver.
2046 * New configure option --with-iconv-bin.
2047 When using the internationalization support like the one in the GNU C
2048 library, GDB will invoke the "iconv" program to get a list of supported
2049 character sets. If this program lives in a non-standard location, one can
2050 use this option to specify where to find it.
2052 * When natively debugging programs on PowerPC BookE processors running
2053 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2054 watchpoints, which specify a mask in addition to an address to watch.
2055 The mask specifies that some bits of an address (the bits which are
2056 reset in the mask) should be ignored when matching the address accessed
2057 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2058 section in the user manual for more details.
2060 * The new option --once causes GDBserver to stop listening for connections once
2061 the first connection is made. The listening port used by GDBserver will
2062 become available after that.
2064 * New commands "info macros" and "alias" have been added.
2066 * New function parameters suffix @entry specifies value of function parameter
2067 at the time the function got called. Entry values are available only since
2073 "!" is now an alias of the "shell" command.
2074 Note that no space is needed between "!" and SHELL COMMAND.
2078 watch EXPRESSION mask MASK_VALUE
2079 The watch command now supports the mask argument which allows creation
2080 of masked watchpoints, if the current architecture supports this feature.
2082 info auto-load-scripts [REGEXP]
2083 This command was formerly named "maintenance print section-scripts".
2084 It is now generally useful and is no longer a maintenance-only command.
2086 info macro [-all] [--] MACRO
2087 The info macro command has new options `-all' and `--'. The first for
2088 printing all definitions of a macro. The second for explicitly specifying
2089 the end of arguments and the beginning of the macro name in case the macro
2090 name starts with a hyphen.
2092 collect[/s] EXPRESSIONS
2093 The tracepoint collect command now takes an optional modifier "/s"
2094 that directs it to dereference pointer-to-character types and
2095 collect the bytes of memory up to a zero byte. The behavior is
2096 similar to what you see when you use the regular print command on a
2097 string. An optional integer following the "/s" sets a bound on the
2098 number of bytes that will be collected.
2101 The trace start command now interprets any supplied arguments as a
2102 note to be recorded with the trace run, with an effect similar to
2103 setting the variable trace-notes.
2106 The trace stop command now interprets any arguments as a note to be
2107 mentioned along with the tstatus report that the trace was stopped
2108 with a command. The effect is similar to setting the variable
2111 * Tracepoints can now be enabled and disabled at any time after a trace
2112 experiment has been started using the standard "enable" and "disable"
2113 commands. It is now possible to start a trace experiment with no enabled
2114 tracepoints; GDB will display a warning, but will allow the experiment to
2115 begin, assuming that tracepoints will be enabled as needed while the trace
2118 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2119 locations with 4-byte instructions, when they were previously
2120 limited to locations with instructions of 5 bytes or longer.
2124 set debug dwarf2-read
2125 show debug dwarf2-read
2126 Turns on or off display of debugging messages related to reading
2127 DWARF debug info. The default is off.
2129 set debug symtab-create
2130 show debug symtab-create
2131 Turns on or off display of debugging messages related to symbol table
2132 creation. The default is off.
2135 show extended-prompt
2136 Set the GDB prompt, and allow escape sequences to be inserted to
2137 display miscellaneous information (see 'help set extended-prompt'
2138 for the list of sequences). This prompt (and any information
2139 accessed through the escape sequences) is updated every time the
2140 prompt is displayed.
2142 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2143 show print entry-values
2144 Set printing of frame argument values at function entry. In some cases
2145 GDB can determine the value of function argument which was passed by the
2146 function caller, even if the value was modified inside the called function.
2148 set debug entry-values
2149 show debug entry-values
2150 Control display of debugging info for determining frame argument values at
2151 function entry and virtual tail call frames.
2153 set basenames-may-differ
2154 show basenames-may-differ
2155 Set whether a source file may have multiple base names.
2156 (A "base name" is the name of a file with the directory part removed.
2157 Example: The base name of "/home/user/hello.c" is "hello.c".)
2158 If set, GDB will canonicalize file names (e.g., expand symlinks)
2159 before comparing them. Canonicalization is an expensive operation,
2160 but it allows the same file be known by more than one base name.
2161 If not set (the default), all source files are assumed to have just
2162 one base name, and gdb will do file name comparisons more efficiently.
2168 Set a user name and notes for the current and any future trace runs.
2169 This is useful for long-running and/or disconnected traces, to
2170 inform others (or yourself) as to who is running the trace, supply
2171 contact information, or otherwise explain what is going on.
2173 set trace-stop-notes
2174 show trace-stop-notes
2175 Set a note attached to the trace run, that is displayed when the
2176 trace has been stopped by a tstop command. This is useful for
2177 instance as an explanation, if you are stopping a trace run that was
2178 started by someone else.
2180 * New remote packets
2184 Dynamically enable a tracepoint in a started trace experiment.
2188 Dynamically disable a tracepoint in a started trace experiment.
2192 Set the user and notes of the trace run.
2196 Query the current status of a tracepoint.
2200 Query the minimum length of instruction at which a fast tracepoint may
2203 * Dcache size (number of lines) and line-size are now runtime-configurable
2204 via "set dcache line" and "set dcache line-size" commands.
2208 Texas Instruments TMS320C6x tic6x-*-*
2212 Renesas RL78 rl78-*-elf
2214 *** Changes in GDB 7.3.1
2216 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2218 *** Changes in GDB 7.3
2220 * GDB has a new command: "thread find [REGEXP]".
2221 It finds the thread id whose name, target id, or thread extra info
2222 matches the given regular expression.
2224 * The "catch syscall" command now works on mips*-linux* targets.
2226 * The -data-disassemble MI command now supports modes 2 and 3 for
2227 dumping the instruction opcodes.
2229 * New command line options
2231 -data-directory DIR Specify DIR as the "data-directory".
2232 This is mostly for testing purposes.
2234 * The "maint set python auto-load on|off" command has been renamed to
2235 "set auto-load-scripts on|off".
2237 * GDB has a new command: "set directories".
2238 It is like the "dir" command except that it replaces the
2239 source path list instead of augmenting it.
2241 * GDB now understands thread names.
2243 On GNU/Linux, "info threads" will display the thread name as set by
2244 prctl or pthread_setname_np.
2246 There is also a new command, "thread name", which can be used to
2247 assign a name internally for GDB to display.
2250 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2251 has been integrated into GDB.
2255 ** The function gdb.Write now accepts an optional keyword 'stream'.
2256 This keyword, when provided, will direct the output to either
2257 stdout, stderr, or GDB's logging output.
2259 ** Parameters can now be be sub-classed in Python, and in particular
2260 you may implement the get_set_doc and get_show_doc functions.
2261 This improves how Parameter set/show documentation is processed
2262 and allows for more dynamic content.
2264 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2265 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2266 have an is_valid method.
2268 ** Breakpoints can now be sub-classed in Python, and in particular
2269 you may implement a 'stop' function that is executed each time
2270 the inferior reaches that breakpoint.
2272 ** New function gdb.lookup_global_symbol looks up a global symbol.
2274 ** GDB values in Python are now callable if the value represents a
2275 function. For example, if 'some_value' represents a function that
2276 takes two integer parameters and returns a value, you can call
2277 that function like so:
2279 result = some_value (10,20)
2281 ** Module gdb.types has been added.
2282 It contains a collection of utilities for working with gdb.Types objects:
2283 get_basic_type, has_field, make_enum_dict.
2285 ** Module gdb.printing has been added.
2286 It contains utilities for writing and registering pretty-printers.
2287 New classes: PrettyPrinter, SubPrettyPrinter,
2288 RegexpCollectionPrettyPrinter.
2289 New function: register_pretty_printer.
2291 ** New commands "info pretty-printers", "enable pretty-printer" and
2292 "disable pretty-printer" have been added.
2294 ** gdb.parameter("directories") is now available.
2296 ** New function gdb.newest_frame returns the newest frame in the
2299 ** The gdb.InferiorThread class has a new "name" attribute. This
2300 holds the thread's name.
2302 ** Python Support for Inferior events.
2303 Python scripts can add observers to be notified of events
2304 occurring in the process being debugged.
2305 The following events are currently supported:
2306 - gdb.events.cont Continue event.
2307 - gdb.events.exited Inferior exited event.
2308 - gdb.events.stop Signal received, and Breakpoint hit events.
2312 ** GDB now puts template parameters in scope when debugging in an
2313 instantiation. For example, if you have:
2315 template<int X> int func (void) { return X; }
2317 then if you step into func<5>, "print X" will show "5". This
2318 feature requires proper debuginfo support from the compiler; it
2319 was added to GCC 4.5.
2321 ** The motion commands "next", "finish", "until", and "advance" now
2322 work better when exceptions are thrown. In particular, GDB will
2323 no longer lose control of the inferior; instead, the GDB will
2324 stop the inferior at the point at which the exception is caught.
2325 This functionality requires a change in the exception handling
2326 code that was introduced in GCC 4.5.
2328 * GDB now follows GCC's rules on accessing volatile objects when
2329 reading or writing target state during expression evaluation.
2330 One notable difference to prior behavior is that "print x = 0"
2331 no longer generates a read of x; the value of the assignment is
2332 now always taken directly from the value being assigned.
2334 * GDB now has some support for using labels in the program's source in
2335 linespecs. For instance, you can use "advance label" to continue
2336 execution to a label.
2338 * GDB now has support for reading and writing a new .gdb_index
2339 section. This section holds a fast index of DWARF debugging
2340 information and can be used to greatly speed up GDB startup and
2341 operation. See the documentation for `save gdb-index' for details.
2343 * The "watch" command now accepts an optional "-location" argument.
2344 When used, this causes GDB to watch the memory referred to by the
2345 expression. Such a watchpoint is never deleted due to it going out
2348 * GDB now supports thread debugging of core dumps on GNU/Linux.
2350 GDB now activates thread debugging using the libthread_db library
2351 when debugging GNU/Linux core dumps, similarly to when debugging
2352 live processes. As a result, when debugging a core dump file, GDB
2353 is now able to display pthread_t ids of threads. For example, "info
2354 threads" shows the same output as when debugging the process when it
2355 was live. In earlier releases, you'd see something like this:
2358 * 1 LWP 6780 main () at main.c:10
2360 While now you see this:
2363 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2365 It is also now possible to inspect TLS variables when debugging core
2368 When debugging a core dump generated on a machine other than the one
2369 used to run GDB, you may need to point GDB at the correct
2370 libthread_db library with the "set libthread-db-search-path"
2371 command. See the user manual for more details on this command.
2373 * When natively debugging programs on PowerPC BookE processors running
2374 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2375 which stop execution of the inferior whenever it executes an instruction
2376 at any address within the specified range. See the "PowerPC Embedded"
2377 section in the user manual for more details.
2379 * New features in the GDB remote stub, GDBserver
2381 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2382 and i686 LynxOS (version 5.x).
2384 ** GDBserver is now supported on Blackfin Linux.
2386 * New native configurations
2388 ia64 HP-UX ia64-*-hpux*
2392 Analog Devices, Inc. Blackfin Processor bfin-*
2394 * Ada task switching is now supported on sparc-elf targets when
2395 debugging a program using the Ravenscar Profile. For more information,
2396 see the "Tasking Support when using the Ravenscar Profile" section
2397 in the GDB user manual.
2399 * Guile support was removed.
2401 * New features in the GNU simulator
2403 ** The --map-info flag lists all known core mappings.
2405 ** CFI flashes may be simulated via the "cfi" device.
2407 *** Changes in GDB 7.2
2409 * Shared library support for remote targets by default
2411 When GDB is configured for a generic, non-OS specific target, like
2412 for example, --target=arm-eabi or one of the many *-*-elf targets,
2413 GDB now queries remote stubs for loaded shared libraries using the
2414 `qXfer:libraries:read' packet. Previously, shared library support
2415 was always disabled for such configurations.
2419 ** Argument Dependent Lookup (ADL)
2421 In C++ ADL lookup directs function search to the namespaces of its
2422 arguments even if the namespace has not been imported.
2432 Here the compiler will search for `foo' in the namespace of 'b'
2433 and find A::foo. GDB now supports this. This construct is commonly
2434 used in the Standard Template Library for operators.
2436 ** Improved User Defined Operator Support
2438 In addition to member operators, GDB now supports lookup of operators
2439 defined in a namespace and imported with a `using' directive, operators
2440 defined in the global scope, operators imported implicitly from an
2441 anonymous namespace, and the ADL operators mentioned in the previous
2443 GDB now also supports proper overload resolution for all the previously
2444 mentioned flavors of operators.
2446 ** static const class members
2448 Printing of static const class members that are initialized in the
2449 class definition has been fixed.
2451 * Windows Thread Information Block access.
2453 On Windows targets, GDB now supports displaying the Windows Thread
2454 Information Block (TIB) structure. This structure is visible either
2455 by using the new command `info w32 thread-information-block' or, by
2456 dereferencing the new convenience variable named `$_tlb', a
2457 thread-specific pointer to the TIB. This feature is also supported
2458 when remote debugging using GDBserver.
2460 * Static tracepoints
2462 Static tracepoints are calls in the user program into a tracing
2463 library. One such library is a port of the LTTng kernel tracer to
2464 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2465 When debugging with GDBserver, GDB now supports combining the GDB
2466 tracepoint machinery with such libraries. For example: the user can
2467 use GDB to probe a static tracepoint marker (a call from the user
2468 program into the tracing library) with the new "strace" command (see
2469 "New commands" below). This creates a "static tracepoint" in the
2470 breakpoint list, that can be manipulated with the same feature set
2471 as fast and regular tracepoints. E.g., collect registers, local and
2472 global variables, collect trace state variables, and define
2473 tracepoint conditions. In addition, the user can collect extra
2474 static tracepoint marker specific data, by collecting the new
2475 $_sdata internal variable. When analyzing the trace buffer, you can
2476 inspect $_sdata like any other variable available to GDB. For more
2477 information, see the "Tracepoints" chapter in GDB user manual. New
2478 remote packets have been defined to support static tracepoints, see
2479 the "New remote packets" section below.
2481 * Better reconstruction of tracepoints after disconnected tracing
2483 GDB will attempt to download the original source form of tracepoint
2484 definitions when starting a trace run, and then will upload these
2485 upon reconnection to the target, resulting in a more accurate
2486 reconstruction of the tracepoints that are in use on the target.
2490 You can now exercise direct control over the ways that GDB can
2491 affect your program. For instance, you can disallow the setting of
2492 breakpoints, so that the program can run continuously (assuming
2493 non-stop mode). In addition, the "observer" variable is available
2494 to switch all of the different controls; in observer mode, GDB
2495 cannot affect the target's behavior at all, which is useful for
2496 tasks like diagnosing live systems in the field.
2498 * The new convenience variable $_thread holds the number of the
2501 * New remote packets
2505 Return the address of the Windows Thread Information Block of a given thread.
2509 In response to several of the tracepoint packets, the target may now
2510 also respond with a number of intermediate `qRelocInsn' request
2511 packets before the final result packet, to have GDB handle
2512 relocating an instruction to execute at a different address. This
2513 is particularly useful for stubs that support fast tracepoints. GDB
2514 reports support for this feature in the qSupported packet.
2518 List static tracepoint markers in the target program.
2522 List static tracepoint markers at a given address in the target
2525 qXfer:statictrace:read
2527 Read the static trace data collected (by a `collect $_sdata'
2528 tracepoint action). The remote stub reports support for this packet
2529 to gdb's qSupported query.
2533 Send the current settings of GDB's permission flags.
2537 Send part of the source (textual) form of a tracepoint definition,
2538 which includes location, conditional, and action list.
2540 * The source command now accepts a -s option to force searching for the
2541 script in the source search path even if the script name specifies
2544 * New features in the GDB remote stub, GDBserver
2546 - GDBserver now support tracepoints (including fast tracepoints, and
2547 static tracepoints). The feature is currently supported by the
2548 i386-linux and amd64-linux builds. See the "Tracepoints support
2549 in gdbserver" section in the manual for more information.
2551 GDBserver JIT compiles the tracepoint's conditional agent
2552 expression bytecode into native code whenever possible for low
2553 overhead dynamic tracepoints conditionals. For such tracepoints,
2554 an expression that examines program state is evaluated when the
2555 tracepoint is reached, in order to determine whether to capture
2556 trace data. If the condition is simple and false, processing the
2557 tracepoint finishes very quickly and no data is gathered.
2559 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2560 for static tracepoints support.
2562 - GDBserver now supports x86_64 Windows 64-bit debugging.
2564 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2565 it understands register description.
2567 * The --batch flag now disables pagination and queries.
2569 * X86 general purpose registers
2571 GDB now supports reading/writing byte, word and double-word x86
2572 general purpose registers directly. This means you can use, say,
2573 $ah or $ax to refer, respectively, to the byte register AH and
2574 16-bit word register AX that are actually portions of the 32-bit
2575 register EAX or 64-bit register RAX.
2577 * The `commands' command now accepts a range of breakpoints to modify.
2578 A plain `commands' following a command that creates multiple
2579 breakpoints affects all the breakpoints set by that command. This
2580 applies to breakpoints set by `rbreak', and also applies when a
2581 single `break' command creates multiple breakpoints (e.g.,
2582 breakpoints on overloaded c++ functions).
2584 * The `rbreak' command now accepts a filename specification as part of
2585 its argument, limiting the functions selected by the regex to those
2586 in the specified file.
2588 * Support for remote debugging Windows and SymbianOS shared libraries
2589 from Unix hosts has been improved. Non Windows GDB builds now can
2590 understand target reported file names that follow MS-DOS based file
2591 system semantics, such as file names that include drive letters and
2592 use the backslash character as directory separator. This makes it
2593 possible to transparently use the "set sysroot" and "set
2594 solib-search-path" on Unix hosts to point as host copies of the
2595 target's shared libraries. See the new command "set
2596 target-file-system-kind" described below, and the "Commands to
2597 specify files" section in the user manual for more information.
2601 eval template, expressions...
2602 Convert the values of one or more expressions under the control
2603 of the string template to a command line, and call it.
2605 set target-file-system-kind unix|dos-based|auto
2606 show target-file-system-kind
2607 Set or show the assumed file system kind for target reported file
2610 save breakpoints <filename>
2611 Save all current breakpoint definitions to a file suitable for use
2612 in a later debugging session. To read the saved breakpoint
2613 definitions, use the `source' command.
2615 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2618 info static-tracepoint-markers
2619 Display information about static tracepoint markers in the target.
2621 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2622 Define a static tracepoint by probing a marker at the given
2623 function, line, address, or marker ID.
2627 Enable and disable observer mode.
2629 set may-write-registers on|off
2630 set may-write-memory on|off
2631 set may-insert-breakpoints on|off
2632 set may-insert-tracepoints on|off
2633 set may-insert-fast-tracepoints on|off
2634 set may-interrupt on|off
2635 Set individual permissions for GDB effects on the target. Note that
2636 some of these settings can have undesirable or surprising
2637 consequences, particularly when changed in the middle of a session.
2638 For instance, disabling the writing of memory can prevent
2639 breakpoints from being inserted, cause single-stepping to fail, or
2640 even crash your program, if you disable after breakpoints have been
2641 inserted. However, GDB should not crash.
2643 set record memory-query on|off
2644 show record memory-query
2645 Control whether to stop the inferior if memory changes caused
2646 by an instruction cannot be recorded.
2651 The disassemble command now supports "start,+length" form of two arguments.
2655 ** GDB now provides a new directory location, called the python directory,
2656 where Python scripts written for GDB can be installed. The location
2657 of that directory is <data-directory>/python, where <data-directory>
2658 is the GDB data directory. For more details, see section `Scripting
2659 GDB using Python' in the manual.
2661 ** The GDB Python API now has access to breakpoints, symbols, symbol
2662 tables, program spaces, inferiors, threads and frame's code blocks.
2663 Additionally, GDB Parameters can now be created from the API, and
2664 manipulated via set/show in the CLI.
2666 ** New functions gdb.target_charset, gdb.target_wide_charset,
2667 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2669 ** New exception gdb.GdbError.
2671 ** Pretty-printers are now also looked up in the current program space.
2673 ** Pretty-printers can now be individually enabled and disabled.
2675 ** GDB now looks for names of Python scripts to auto-load in a
2676 special section named `.debug_gdb_scripts', in addition to looking
2677 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2679 * Tracepoint actions were unified with breakpoint commands. In particular,
2680 there are no longer differences in "info break" output for breakpoints and
2681 tracepoints and the "commands" command can be used for both tracepoints and
2682 regular breakpoints.
2686 ARM Symbian arm*-*-symbianelf*
2688 * D language support.
2689 GDB now supports debugging programs written in the D programming
2692 * GDB now supports the extended ptrace interface for PowerPC which is
2693 available since Linux kernel version 2.6.34. This automatically enables
2694 any hardware breakpoints and additional hardware watchpoints available in
2695 the processor. The old ptrace interface exposes just one hardware
2696 watchpoint and no hardware breakpoints.
2698 * GDB is now able to use the Data Value Compare (DVC) register available on
2699 embedded PowerPC processors to implement in hardware simple watchpoint
2700 conditions of the form:
2702 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2704 This works in native GDB running on Linux kernels with the extended ptrace
2705 interface mentioned above.
2707 *** Changes in GDB 7.1
2711 ** Namespace Support
2713 GDB now supports importing of namespaces in C++. This enables the
2714 user to inspect variables from imported namespaces. Support for
2715 namepace aliasing has also been added. So, if a namespace is
2716 aliased in the current scope (e.g. namepace C=A; ) the user can
2717 print variables using the alias (e.g. (gdb) print C::x).
2721 All known bugs relating to the printing of virtual base class were
2722 fixed. It is now possible to call overloaded static methods using a
2727 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2728 and reinterpret_cast<> are now handled by the C++ expression parser.
2732 Xilinx MicroBlaze microblaze-*-*
2737 Xilinx MicroBlaze microblaze
2740 * Multi-program debugging.
2742 GDB now has support for multi-program (a.k.a. multi-executable or
2743 multi-exec) debugging. This allows for debugging multiple inferiors
2744 simultaneously each running a different program under the same GDB
2745 session. See "Debugging Multiple Inferiors and Programs" in the
2746 manual for more information. This implied some user visible changes
2747 in the multi-inferior support. For example, "info inferiors" now
2748 lists inferiors that are not running yet or that have exited
2749 already. See also "New commands" and "New options" below.
2751 * New tracing features
2753 GDB's tracepoint facility now includes several new features:
2755 ** Trace state variables
2757 GDB tracepoints now include support for trace state variables, which
2758 are variables managed by the target agent during a tracing
2759 experiment. They are useful for tracepoints that trigger each
2760 other, so for instance one tracepoint can count hits in a variable,
2761 and then a second tracepoint has a condition that is true when the
2762 count reaches a particular value. Trace state variables share the
2763 $-syntax of GDB convenience variables, and can appear in both
2764 tracepoint actions and condition expressions. Use the "tvariable"
2765 command to create, and "info tvariables" to view; see "Trace State
2766 Variables" in the manual for more detail.
2770 GDB now includes an option for defining fast tracepoints, which
2771 targets may implement more efficiently, such as by installing a jump
2772 into the target agent rather than a trap instruction. The resulting
2773 speedup can be by two orders of magnitude or more, although the
2774 tradeoff is that some program locations on some target architectures
2775 might not allow fast tracepoint installation, for instance if the
2776 instruction to be replaced is shorter than the jump. To request a
2777 fast tracepoint, use the "ftrace" command, with syntax identical to
2778 the regular trace command.
2780 ** Disconnected tracing
2782 It is now possible to detach GDB from the target while it is running
2783 a trace experiment, then reconnect later to see how the experiment
2784 is going. In addition, a new variable disconnected-tracing lets you
2785 tell the target agent whether to continue running a trace if the
2786 connection is lost unexpectedly.
2790 GDB now has the ability to save the trace buffer into a file, and
2791 then use that file as a target, similarly to you can do with
2792 corefiles. You can select trace frames, print data that was
2793 collected in them, and use tstatus to display the state of the
2794 tracing run at the moment that it was saved. To create a trace
2795 file, use "tsave <filename>", and to use it, do "target tfile
2798 ** Circular trace buffer
2800 You can ask the target agent to handle the trace buffer as a
2801 circular buffer, discarding the oldest trace frames to make room for
2802 newer ones, by setting circular-trace-buffer to on. This feature may
2803 not be available for all target agents.
2808 The disassemble command, when invoked with two arguments, now requires
2809 the arguments to be comma-separated.
2812 The info variables command now displays variable definitions. Files
2813 which only declare a variable are not shown.
2816 The source command is now capable of sourcing Python scripts.
2817 This feature is dependent on the debugger being build with Python
2820 Related to this enhancement is also the introduction of a new command
2821 "set script-extension" (see below).
2823 * New commands (for set/show, see "New options" below)
2825 record save [<FILENAME>]
2826 Save a file (in core file format) containing the process record
2827 execution log for replay debugging at a later time.
2829 record restore <FILENAME>
2830 Restore the process record execution log that was saved at an
2831 earlier time, for replay debugging.
2833 add-inferior [-copies <N>] [-exec <FILENAME>]
2836 clone-inferior [-copies <N>] [ID]
2837 Make a new inferior ready to execute the same program another
2838 inferior has loaded.
2843 maint info program-spaces
2844 List the program spaces loaded into GDB.
2846 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2847 show remote interrupt-sequence
2848 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2849 as the sequence to the remote target in order to interrupt the execution.
2850 Ctrl-C is a default. Some system prefers BREAK which is high level of
2851 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2852 Magic SysRq g. It is BREAK signal and character 'g'.
2854 set remote interrupt-on-connect [on | off]
2855 show remote interrupt-on-connect
2856 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2857 remote target when gdb connects to it. This is needed when you debug
2860 set remotebreak [on | off]
2862 Deprecated. Use "set/show remote interrupt-sequence" instead.
2864 tvariable $NAME [ = EXP ]
2865 Create or modify a trace state variable.
2868 List trace state variables and their values.
2870 delete tvariable $NAME ...
2871 Delete one or more trace state variables.
2874 Evaluate the given expressions without collecting anything into the
2875 trace buffer. (Valid in tracepoint actions only.)
2877 ftrace FN / FILE:LINE / *ADDR
2878 Define a fast tracepoint at the given function, line, or address.
2880 * New expression syntax
2882 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2883 GDB now parses 0b101010 identically with 42.
2887 set follow-exec-mode new|same
2888 show follow-exec-mode
2889 Control whether GDB reuses the same inferior across an exec call or
2890 creates a new one. This is useful to be able to restart the old
2891 executable after the inferior having done an exec call.
2893 set default-collect EXPR, ...
2894 show default-collect
2895 Define a list of expressions to be collected at each tracepoint.
2896 This is a useful way to ensure essential items are not overlooked,
2897 such as registers or a critical global variable.
2899 set disconnected-tracing
2900 show disconnected-tracing
2901 If set to 1, the target is instructed to continue tracing if it
2902 loses its connection to GDB. If 0, the target is to stop tracing
2905 set circular-trace-buffer
2906 show circular-trace-buffer
2907 If set to on, the target is instructed to use a circular trace buffer
2908 and discard the oldest trace frames instead of stopping the trace due
2909 to a full trace buffer. If set to off, the trace stops when the buffer
2910 fills up. Some targets may not support this.
2912 set script-extension off|soft|strict
2913 show script-extension
2914 If set to "off", the debugger does not perform any script language
2915 recognition, and all sourced files are assumed to be GDB scripts.
2916 If set to "soft" (the default), files are sourced according to
2917 filename extension, falling back to GDB scripts if the first
2919 If set to "strict", files are sourced according to filename extension.
2921 set ada trust-PAD-over-XVS on|off
2922 show ada trust-PAD-over-XVS
2923 If off, activate a workaround against a bug in the debugging information
2924 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2925 the GCC sources for more information about the GNAT encoding and
2926 PAD types in particular). It is always safe to set this option to
2927 off, but this introduces a slight performance penalty. The default
2930 * Python API Improvements
2932 ** GDB provides the new class gdb.LazyString. This is useful in
2933 some pretty-printing cases. The new method gdb.Value.lazy_string
2934 provides a simple way to create objects of this type.
2936 ** The fields returned by gdb.Type.fields now have an
2937 `is_base_class' attribute.
2939 ** The new method gdb.Type.range returns the range of an array type.
2941 ** The new method gdb.parse_and_eval can be used to parse and
2942 evaluate an expression.
2944 * New remote packets
2947 Define a trace state variable.
2950 Get the current value of a trace state variable.
2953 Set desired tracing behavior upon disconnection.
2956 Set the trace buffer to be linear or circular.
2959 Get data about the tracepoints currently in use.
2963 Process record now works correctly with hardware watchpoints.
2965 Multiple bug fixes have been made to the mips-irix port, making it
2966 much more reliable. In particular:
2967 - Debugging threaded applications is now possible again. Previously,
2968 GDB would hang while starting the program, or while waiting for
2969 the program to stop at a breakpoint.
2970 - Attaching to a running process no longer hangs.
2971 - An error occurring while loading a core file has been fixed.
2972 - Changing the value of the PC register now works again. This fixes
2973 problems observed when using the "jump" command, or when calling
2974 a function from GDB, or even when assigning a new value to $pc.
2975 - With the "finish" and "return" commands, the return value for functions
2976 returning a small array is now correctly printed.
2977 - It is now possible to break on shared library code which gets executed
2978 during a shared library init phase (code executed while executing
2979 their .init section). Previously, the breakpoint would have no effect.
2980 - GDB is now able to backtrace through the signal handler for
2981 non-threaded programs.
2983 PIE (Position Independent Executable) programs debugging is now supported.
2984 This includes debugging execution of PIC (Position Independent Code) shared
2985 libraries although for that, it should be possible to run such libraries as an
2988 *** Changes in GDB 7.0
2990 * GDB now has an interface for JIT compilation. Applications that
2991 dynamically generate code can create symbol files in memory and register
2992 them with GDB. For users, the feature should work transparently, and
2993 for JIT developers, the interface is documented in the GDB manual in the
2994 "JIT Compilation Interface" chapter.
2996 * Tracepoints may now be conditional. The syntax is as for
2997 breakpoints; either an "if" clause appended to the "trace" command,
2998 or the "condition" command is available. GDB sends the condition to
2999 the target for evaluation using the same bytecode format as is used
3000 for tracepoint actions.
3002 * The disassemble command now supports: an optional /r modifier, print the
3003 raw instructions in hex as well as in symbolic form, and an optional /m
3004 modifier to print mixed source+assembly.
3006 * Process record and replay
3008 In a architecture environment that supports ``process record and
3009 replay'', ``process record and replay'' target can record a log of
3010 the process execution, and replay it with both forward and reverse
3013 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3014 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3015 set execution-direction {forward|reverse}, for targets that support
3018 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3019 feature is available with a native GDB running on kernel version
3022 * GDB now has support for multi-byte and wide character sets on the
3023 target. Strings whose character type is wchar_t, char16_t, or
3024 char32_t are now correctly printed. GDB supports wide- and unicode-
3025 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3026 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3027 `printf'. This feature requires iconv to work properly; if your
3028 system does not have a working iconv, GDB can use GNU libiconv. See
3029 the installation instructions for more information.
3031 * GDB now supports automatic retrieval of shared library files from
3032 remote targets. To use this feature, specify a system root that begins
3033 with the `remote:' prefix, either via the `set sysroot' command or via
3034 the `--with-sysroot' configure-time option.
3036 * "info sharedlibrary" now takes an optional regex of libraries to show,
3037 and it now reports if a shared library has no debugging information.
3039 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3040 now complete on file names.
3042 * When completing in expressions, gdb will attempt to limit
3043 completions to allowable structure or union fields, where appropriate.
3044 For instance, consider:
3046 # struct example { int f1; double f2; };
3047 # struct example variable;
3050 If the user types TAB at the end of this command line, the available
3051 completions will be "f1" and "f2".
3053 * Inlined functions are now supported. They show up in backtraces, and
3054 the "step", "next", and "finish" commands handle them automatically.
3056 * GDB now supports the token-splicing (##) and stringification (#)
3057 operators when expanding macros. It also supports variable-arity
3060 * GDB now supports inspecting extra signal information, exported by
3061 the new $_siginfo convenience variable. The feature is currently
3062 implemented on linux ARM, i386 and amd64.
3064 * GDB can now display the VFP floating point registers and NEON vector
3065 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3066 can provide these registers (requires Linux 2.6.30 or later). Remote
3067 and simulator targets may also provide them.
3069 * New remote packets
3072 Search memory for a sequence of bytes.
3075 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3076 operation over reliable transport links. Use of this packet is
3077 controlled by the `set remote noack-packet' command.
3080 Kill the process with the specified process ID. Use this in preference
3081 to `k' when multiprocess protocol extensions are supported.
3084 Obtains additional operating system information
3088 Read or write additional signal information.
3090 * Removed remote protocol undocumented extension
3092 An undocumented extension to the remote protocol's `S' stop reply
3093 packet that permited the stub to pass a process id was removed.
3094 Remote servers should use the `T' stop reply packet instead.
3096 * GDB now supports multiple function calling conventions according to the
3097 DWARF-2 DW_AT_calling_convention function attribute.
3099 * The SH target utilizes the aforementioned change to distinguish between gcc
3100 and Renesas calling convention. It also adds the new CLI commands
3101 `set/show sh calling-convention'.
3103 * GDB can now read compressed debug sections, as produced by GNU gold
3104 with the --compress-debug-sections=zlib flag.
3106 * 64-bit core files are now supported on AIX.
3108 * Thread switching is now supported on Tru64.
3110 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3111 which will be allocated using malloc later in program execution.
3113 * The qXfer:libraries:read remote procotol packet now allows passing a
3114 list of section offsets.
3116 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3117 conditions handling signals delivered during attach or thread creation
3118 have also been fixed.
3120 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3121 From the user's standpoint, all unqualified instances of True and False
3122 are treated as the standard definitions, regardless of context.
3124 * GDB now parses C++ symbol and type names more flexibly. For
3127 template<typename T> class C { };
3130 GDB will now correctly handle all of:
3132 ptype C<char const *>
3133 ptype C<char const*>
3134 ptype C<const char *>
3135 ptype C<const char*>
3137 * New features in the GDB remote stub, gdbserver
3139 - The "--wrapper" command-line argument tells gdbserver to use a
3140 wrapper program to launch programs for debugging.
3142 - On PowerPC and S/390 targets, it is now possible to use a single
3143 gdbserver executable to debug both 32-bit and 64-bit programs.
3144 (This requires gdbserver itself to be built as a 64-bit executable.)
3146 - gdbserver uses the new noack protocol mode for TCP connections to
3147 reduce communications latency, if also supported and enabled in GDB.
3149 - Support for the sparc64-linux-gnu target is now included in
3152 - The amd64-linux build of gdbserver now supports debugging both
3153 32-bit and 64-bit programs.
3155 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3156 now support hardware watchpoints, and will use them automatically
3161 GDB now has support for scripting using Python. Whether this is
3162 available is determined at configure time.
3164 New GDB commands can now be written in Python.
3166 * Ada tasking support
3168 Ada tasks can now be inspected in GDB. The following commands have
3172 Print the list of Ada tasks.
3174 Print detailed information about task number N.
3176 Print the task number of the current task.
3178 Switch the context of debugging to task number N.
3180 * Support for user-defined prefixed commands. The "define" command can
3181 add new commands to existing prefixes, e.g. "target".
3183 * Multi-inferior, multi-process debugging.
3185 GDB now has generalized support for multi-inferior debugging. See
3186 "Debugging Multiple Inferiors" in the manual for more information.
3187 Although availability still depends on target support, the command
3188 set is more uniform now. The GNU/Linux specific multi-forks support
3189 has been migrated to this new framework. This implied some user
3190 visible changes; see "New commands" and also "Removed commands"
3193 * Target descriptions can now describe the target OS ABI. See the
3194 "Target Description Format" section in the user manual for more
3197 * Target descriptions can now describe "compatible" architectures
3198 to indicate that the target can execute applications for a different
3199 architecture in addition to those for the main target architecture.
3200 See the "Target Description Format" section in the user manual for
3203 * Multi-architecture debugging.
3205 GDB now includes general supports for debugging applications on
3206 hybrid systems that use more than one single processor architecture
3207 at the same time. Each such hybrid architecture still requires
3208 specific support to be added. The only hybrid architecture supported
3209 in this version of GDB is the Cell Broadband Engine.
3211 * GDB now supports integrated debugging of Cell/B.E. applications that
3212 use both the PPU and SPU architectures. To enable support for hybrid
3213 Cell/B.E. debugging, you need to configure GDB to support both the
3214 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3215 --enable-targets configure option.
3217 * Non-stop mode debugging.
3219 For some targets, GDB now supports an optional mode of operation in
3220 which you can examine stopped threads while other threads continue
3221 to execute freely. This is referred to as non-stop mode, with the
3222 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3223 section in the user manual for more information.
3225 To be able to support remote non-stop debugging, a remote stub needs
3226 to implement the non-stop mode remote protocol extensions, as
3227 described in the "Remote Non-Stop" section of the user manual. The
3228 GDB remote stub, gdbserver, has been adjusted to support these
3229 extensions on linux targets.
3231 * New commands (for set/show, see "New options" below)
3233 catch syscall [NAME(S) | NUMBER(S)]
3234 Catch system calls. Arguments, which should be names of system
3235 calls or their numbers, mean catch only those syscalls. Without
3236 arguments, every syscall will be caught. When the inferior issues
3237 any of the specified syscalls, GDB will stop and announce the system
3238 call, both when it is called and when its call returns. This
3239 feature is currently available with a native GDB running on the
3240 Linux Kernel, under the following architectures: x86, x86_64,
3241 PowerPC and PowerPC64.
3243 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3245 Search memory for a sequence of bytes.
3247 maint set python print-stack
3248 maint show python print-stack
3249 Show a stack trace when an error is encountered in a Python script.
3252 Invoke CODE by passing it to the Python interpreter.
3257 These allow macros to be defined, undefined, and listed
3261 Show operating system information about processes.
3264 List the inferiors currently under GDB's control.
3267 Switch focus to inferior number NUM.
3270 Detach from inferior number NUM.
3273 Kill inferior number NUM.
3277 set spu stop-on-load
3278 show spu stop-on-load
3279 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3281 set spu auto-flush-cache
3282 show spu auto-flush-cache
3283 Control whether to automatically flush the software-managed cache
3284 during Cell/B.E. debugging.
3286 set sh calling-convention
3287 show sh calling-convention
3288 Control the calling convention used when calling SH target functions.
3291 show debug timestamp
3292 Control display of timestamps with GDB debugging output.
3294 set disassemble-next-line
3295 show disassemble-next-line
3296 Control display of disassembled source lines or instructions when
3299 set remote noack-packet
3300 show remote noack-packet
3301 Set/show the use of remote protocol QStartNoAckMode packet. See above
3302 under "New remote packets."
3304 set remote query-attached-packet
3305 show remote query-attached-packet
3306 Control use of remote protocol `qAttached' (query-attached) packet.
3308 set remote read-siginfo-object
3309 show remote read-siginfo-object
3310 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3313 set remote write-siginfo-object
3314 show remote write-siginfo-object
3315 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3318 set remote reverse-continue
3319 show remote reverse-continue
3320 Control use of remote protocol 'bc' (reverse-continue) packet.
3322 set remote reverse-step
3323 show remote reverse-step
3324 Control use of remote protocol 'bs' (reverse-step) packet.
3326 set displaced-stepping
3327 show displaced-stepping
3328 Control displaced stepping mode. Displaced stepping is a way to
3329 single-step over breakpoints without removing them from the debuggee.
3330 Also known as "out-of-line single-stepping".
3333 show debug displaced
3334 Control display of debugging info for displaced stepping.
3336 maint set internal-error
3337 maint show internal-error
3338 Control what GDB does when an internal error is detected.
3340 maint set internal-warning
3341 maint show internal-warning
3342 Control what GDB does when an internal warning is detected.
3347 Use a wrapper program to launch programs for debugging.
3349 set multiple-symbols (all|ask|cancel)
3350 show multiple-symbols
3351 The value of this variable can be changed to adjust the debugger behavior
3352 when an expression or a breakpoint location contains an ambiguous symbol
3353 name (an overloaded function name, for instance).
3355 set breakpoint always-inserted
3356 show breakpoint always-inserted
3357 Keep breakpoints always inserted in the target, as opposed to inserting
3358 them when resuming the target, and removing them when the target stops.
3359 This option can improve debugger performance on slow remote targets.
3361 set arm fallback-mode (arm|thumb|auto)
3362 show arm fallback-mode
3363 set arm force-mode (arm|thumb|auto)
3365 These commands control how ARM GDB determines whether instructions
3366 are ARM or Thumb. The default for both settings is auto, which uses
3367 the current CPSR value for instructions without symbols; previous
3368 versions of GDB behaved as if "set arm fallback-mode arm".
3370 set disable-randomization
3371 show disable-randomization
3372 Standalone programs run with the virtual address space randomization enabled
3373 by default on some platforms. This option keeps the addresses stable across
3374 multiple debugging sessions.
3378 Control whether other threads are stopped or not when some thread hits
3383 Requests that asynchronous execution is enabled in the target, if available.
3384 In this case, it's possible to resume target in the background, and interact
3385 with GDB while the target is running. "show target-async" displays the
3386 current state of asynchronous execution of the target.
3388 set target-wide-charset
3389 show target-wide-charset
3390 The target-wide-charset is the name of the character set that GDB
3391 uses when printing characters whose type is wchar_t.
3393 set tcp auto-retry (on|off)
3395 set tcp connect-timeout
3396 show tcp connect-timeout
3397 These commands allow GDB to retry failed TCP connections to a remote stub
3398 with a specified timeout period; this is useful if the stub is launched
3399 in parallel with GDB but may not be ready to accept connections immediately.
3401 set libthread-db-search-path
3402 show libthread-db-search-path
3403 Control list of directories which GDB will search for appropriate
3406 set schedule-multiple (on|off)
3407 show schedule-multiple
3408 Allow GDB to resume all threads of all processes or only threads of
3409 the current process.
3413 Use more aggressive caching for accesses to the stack. This improves
3414 performance of remote debugging (particularly backtraces) without
3415 affecting correctness.
3417 set interactive-mode (on|off|auto)
3418 show interactive-mode
3419 Control whether GDB runs in interactive mode (on) or not (off).
3420 When in interactive mode, GDB waits for the user to answer all
3421 queries. Otherwise, GDB does not wait and assumes the default
3422 answer. When set to auto (the default), GDB determines which
3423 mode to use based on the stdin settings.
3428 For program forks, this is replaced by the new more generic `info
3429 inferiors' command. To list checkpoints, you can still use the
3430 `info checkpoints' command, which was an alias for the `info forks'
3434 Replaced by the new `inferior' command. To switch between
3435 checkpoints, you can still use the `restart' command, which was an
3436 alias for the `fork' command.
3439 This is removed, since some targets don't have a notion of
3440 processes. To switch between processes, you can still use the
3441 `inferior' command using GDB's own inferior number.
3444 For program forks, this is replaced by the new more generic `kill
3445 inferior' command. To delete a checkpoint, you can still use the
3446 `delete checkpoint' command, which was an alias for the `delete
3450 For program forks, this is replaced by the new more generic `detach
3451 inferior' command. To detach a checkpoint, you can still use the
3452 `detach checkpoint' command, which was an alias for the `detach
3455 * New native configurations
3457 x86/x86_64 Darwin i[34567]86-*-darwin*
3459 x86_64 MinGW x86_64-*-mingw*
3463 Lattice Mico32 lm32-*
3464 x86 DICOS i[34567]86-*-dicos*
3465 x86_64 DICOS x86_64-*-dicos*
3468 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3469 (mingw32ce) debugging.
3475 These commands were actually not implemented on any target.
3477 *** Changes in GDB 6.8
3479 * New native configurations
3481 NetBSD/hppa hppa*-*netbsd*
3482 Xtensa GNU/Linux xtensa*-*-linux*
3486 NetBSD/hppa hppa*-*-netbsd*
3487 Xtensa GNU/Lunux xtensa*-*-linux*
3489 * Change in command line behavior -- corefiles vs. process ids.
3491 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3492 attaching to process NUMBER fails, GDB no longer attempts to open a
3493 core file named NUMBER. Attaching to a program using the -c option
3494 is no longer supported. Instead, use the '-p' or '--pid' options.
3496 * GDB can now be built as a native debugger for debugging Windows x86
3497 (mingw32) Portable Executable (PE) programs.
3499 * Pending breakpoints no longer change their number when their address
3502 * GDB now supports breakpoints with multiple locations,
3503 including breakpoints on C++ constructors, inside C++ templates,
3504 and in inlined functions.
3506 * GDB's ability to debug optimized code has been improved. GDB more
3507 accurately identifies function bodies and lexical blocks that occupy
3508 more than one contiguous range of addresses.
3510 * Target descriptions can now describe registers for PowerPC.
3512 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3513 registers on PowerPC targets.
3515 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3516 targets even when the libthread_db library is not available.
3518 * The GDB remote stub, gdbserver, now supports the new file transfer
3519 commands (remote put, remote get, and remote delete).
3521 * The GDB remote stub, gdbserver, now supports run and attach in
3522 extended-remote mode.
3524 * hppa*64*-*-hpux11* target broken
3525 The debugger is unable to start a program and fails with the following
3526 error: "Error trying to get information about dynamic linker".
3527 The gdb-6.7 release is also affected.
3529 * GDB now supports the --enable-targets= configure option to allow
3530 building a single GDB executable that supports multiple remote
3531 target architectures.
3533 * GDB now supports debugging C and C++ programs which use the
3534 Decimal Floating Point extension. In addition, the PowerPC target
3535 now has a set of pseudo-registers to inspect decimal float values
3536 stored in two consecutive float registers.
3538 * The -break-insert MI command can optionally create pending
3541 * Improved support for debugging Ada
3542 Many improvements to the Ada language support have been made. These
3544 - Better support for Ada2005 interface types
3545 - Improved handling of arrays and slices in general
3546 - Better support for Taft-amendment types
3547 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3549 - Improved command completion in Ada
3552 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3557 set print frame-arguments (all|scalars|none)
3558 show print frame-arguments
3559 The value of this variable can be changed to control which argument
3560 values should be printed by the debugger when displaying a frame.
3565 Transfer files to and from a remote target, and delete remote files.
3572 Transfer files to and from a remote target, and delete remote files.
3574 * New remote packets
3581 Open, close, read, write, and delete files on the remote system.
3584 Attach to an existing process on the remote system, in extended-remote
3588 Run a new process on the remote system, in extended-remote mode.
3590 *** Changes in GDB 6.7
3592 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3593 bfd, libiberty and opcodes, as revealed by static analysis donated by
3594 Coverity, Inc. (http://scan.coverity.com).
3596 * When looking up multiply-defined global symbols, GDB will now prefer the
3597 symbol definition in the current shared library if it was built using the
3598 -Bsymbolic linker option.
3600 * When the Text User Interface (TUI) is not configured, GDB will now
3601 recognize the -tui command-line option and print a message that the TUI
3604 * The GDB remote stub, gdbserver, now has lower overhead for high
3605 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3607 * GDB for MIPS targets now autodetects whether a remote target provides
3608 32-bit or 64-bit register values.
3610 * Support for C++ member pointers has been improved.
3612 * GDB now understands XML target descriptions, which specify the
3613 target's overall architecture. GDB can read a description from
3614 a local file or over the remote serial protocol.
3616 * Vectors of single-byte data use a new integer type which is not
3617 automatically displayed as character or string data.
3619 * The /s format now works with the print command. It displays
3620 arrays of single-byte integers and pointers to single-byte integers
3623 * Target descriptions can now describe target-specific registers,
3624 for architectures which have implemented the support (currently
3625 only ARM, M68K, and MIPS).
3627 * GDB and the GDB remote stub, gdbserver, now support the XScale
3630 * The GDB remote stub, gdbserver, has been updated to support
3631 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3632 has been rewritten to use the standard GDB remote protocol.
3634 * GDB can now step into C++ functions which are called through thunks.
3636 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3638 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3639 layout. It also supports a TextSeg= and DataSeg= response when only
3640 segment base addresses (rather than offsets) are available.
3642 * The /i format now outputs any trailing branch delay slot instructions
3643 immediately following the last instruction within the count specified.
3645 * The GDB remote protocol "T" stop reply packet now supports a
3646 "library" response. Combined with the new "qXfer:libraries:read"
3647 packet, this response allows GDB to debug shared libraries on targets
3648 where the operating system manages the list of loaded libraries (e.g.
3649 Windows and SymbianOS).
3651 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3652 (DLLs) on Windows and Windows CE targets.
3654 * GDB now supports a faster verification that a .debug file matches its binary
3655 according to its build-id signature, if the signature is present.
3661 Enable or disable hardware flow control (RTS/CTS) on the serial port
3662 when debugging using remote targets.
3664 set mem inaccessible-by-default
3665 show mem inaccessible-by-default
3666 If the target supplies a memory map, for instance via the remote
3667 protocol's "qXfer:memory-map:read" packet, setting this variable
3668 prevents GDB from accessing memory outside the memory map. This
3669 is useful for targets with memory mapped registers or which react
3670 badly to accesses of unmapped address space.
3672 set breakpoint auto-hw
3673 show breakpoint auto-hw
3674 If the target supplies a memory map, for instance via the remote
3675 protocol's "qXfer:memory-map:read" packet, setting this variable
3676 lets GDB use hardware breakpoints automatically for memory regions
3677 where it can not use software breakpoints. This covers both the
3678 "break" command and internal breakpoints used for other commands
3679 including "next" and "finish".
3682 catch exception unhandled
3683 Stop the program execution when Ada exceptions are raised.
3686 Stop the program execution when an Ada assertion failed.
3690 Set an alternate system root for target files. This is a more
3691 general version of "set solib-absolute-prefix", which is now
3692 an alias to "set sysroot".
3695 Provide extended SPU facility status information. This set of
3696 commands is available only when debugging the Cell/B.E. SPU
3699 * New native configurations
3701 OpenBSD/sh sh*-*openbsd*
3704 unset tdesc filename
3706 Use the specified local file as an XML target description, and do
3707 not query the target for its built-in description.
3711 OpenBSD/sh sh*-*-openbsd*
3712 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3713 Toshiba Media Processor mep-elf
3715 * New remote packets
3718 Ignore the specified signals; pass them directly to the debugged program
3719 without stopping other threads or reporting them to GDB.
3721 qXfer:features:read:
3722 Read an XML target description from the target, which describes its
3727 Read or write contents of an spufs file on the target system. These
3728 packets are available only on the Cell/B.E. SPU architecture.
3730 qXfer:libraries:read:
3731 Report the loaded shared libraries. Combined with new "T" packet
3732 response, this packet allows GDB to debug shared libraries on
3733 targets where the operating system manages the list of loaded
3734 libraries (e.g. Windows and SymbianOS).
3738 Support for these obsolete configurations has been removed.
3746 i[34567]86-*-lynxos*
3747 i[34567]86-*-netware*
3748 i[34567]86-*-sco3.2v5*
3749 i[34567]86-*-sco3.2v4*
3751 i[34567]86-*-sysv4.2*
3754 i[34567]86-*-unixware2*
3755 i[34567]86-*-unixware*
3764 * Other removed features
3771 Various m68k-only ROM monitors.
3778 Various Renesas ROM monitors and debugging interfaces for SH and
3783 Support for a Macraigor serial interface to on-chip debugging.
3784 GDB does not directly support the newer parallel or USB
3789 A debug information format. The predecessor to DWARF 2 and
3790 DWARF 3, which are still supported.
3792 Support for the HP aCC compiler on HP-UX/PA-RISC
3794 SOM-encapsulated symbolic debugging information, automatic
3795 invocation of pxdb, and the aCC custom C++ ABI. This does not
3796 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3797 with aCC can still be debugged on an assembly level.
3799 MIPS ".pdr" sections
3801 A MIPS-specific format used to describe stack frame layout
3802 in debugging information.
3806 GDB could work with an older version of Guile to debug
3807 the interpreter and Scheme programs running in it.
3809 set mips stack-arg-size
3810 set mips saved-gpreg-size
3812 Use "set mips abi" to control parameter passing for MIPS.
3814 *** Changes in GDB 6.6
3819 Cell Broadband Engine SPU spu-elf
3821 * GDB can now be configured as a cross-debugger targeting native Windows
3822 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3823 running on a Windows system over TCP/IP to debug Windows programs.
3825 * The GDB remote stub, gdbserver, has been updated to support Windows and
3826 Cygwin debugging. Both single-threaded and multi-threaded programs are
3829 * The "set trust-readonly-sections" command works again. This command was
3830 broken in GDB 6.3, 6.4, and 6.5.
3832 * The "load" command now supports writing to flash memory, if the remote
3833 stub provides the required support.
3835 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3836 longer requires symbolic debug information (e.g. DWARF-2).
3841 unset substitute-path
3842 show substitute-path
3843 Manage a list of substitution rules that GDB uses to rewrite the name
3844 of the directories where the sources are located. This can be useful
3845 for instance when the sources were moved to a different location
3846 between compilation and debugging.
3850 Print each CLI command as it is executed. Each command is prefixed with
3851 a number of `+' symbols representing the nesting depth.
3852 The source command now has a `-v' option to enable the same feature.
3856 The ARM Demon monitor support (RDP protocol, "target rdp").
3858 Kernel Object Display, an embedded debugging feature which only worked with
3859 an obsolete version of Cisco IOS.
3861 The 'set download-write-size' and 'show download-write-size' commands.
3863 * New remote packets
3866 Tell a stub about GDB client features, and request remote target features.
3867 The first feature implemented is PacketSize, which allows the target to
3868 specify the size of packets it can handle - to minimize the number of
3869 packets required and improve performance when connected to a remote
3873 Fetch an OS auxilliary vector from the remote stub. This packet is a
3874 more efficient replacement for qPart:auxv:read.
3876 qXfer:memory-map:read:
3877 Fetch a memory map from the remote stub, including information about
3878 RAM, ROM, and flash memory devices.
3883 Erase and program a flash memory device.
3885 * Removed remote packets
3888 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3889 used it, and only gdbserver implemented it.
3891 *** Changes in GDB 6.5
3895 Renesas M32C/M16C m32c-elf
3897 Morpho Technologies ms1 ms1-elf
3901 init-if-undefined Initialize a convenience variable, but
3902 only if it doesn't already have a value.
3904 The following commands are presently only implemented for native GNU/Linux:
3906 checkpoint Save a snapshot of the program state.
3908 restart <n> Return the program state to a
3909 previously saved state.
3911 info checkpoints List currently saved checkpoints.
3913 delete-checkpoint <n> Delete a previously saved checkpoint.
3915 set|show detach-on-fork Tell gdb whether to detach from a newly
3916 forked process, or to keep debugging it.
3918 info forks List forks of the user program that
3919 are available to be debugged.
3921 fork <n> Switch to debugging one of several
3922 forks of the user program that are
3923 available to be debugged.
3925 delete-fork <n> Delete a fork from the list of forks
3926 that are available to be debugged (and
3927 kill the forked process).
3929 detach-fork <n> Delete a fork from the list of forks
3930 that are available to be debugged (and
3931 allow the process to continue).
3935 Morpho Technologies ms2 ms1-elf
3937 * Improved Windows host support
3939 GDB now builds as a cross debugger hosted on i686-mingw32, including
3940 native console support, and remote communications using either
3941 network sockets or serial ports.
3943 * Improved Modula-2 language support
3945 GDB can now print most types in the Modula-2 syntax. This includes:
3946 basic types, set types, record types, enumerated types, range types,
3947 pointer types and ARRAY types. Procedure var parameters are correctly
3948 printed and hexadecimal addresses and character constants are also
3949 written in the Modula-2 syntax. Best results can be obtained by using
3950 GNU Modula-2 together with the -gdwarf-2 command line option.
3954 The ARM rdi-share module.
3956 The Netware NLM debug server.
3958 *** Changes in GDB 6.4
3960 * New native configurations
3962 OpenBSD/arm arm*-*-openbsd*
3963 OpenBSD/mips64 mips64-*-openbsd*
3967 Morpho Technologies ms1 ms1-elf
3969 * New command line options
3971 --batch-silent As for --batch, but totally silent.
3972 --return-child-result The debugger will exist with the same value
3973 the child (debugged) program exited with.
3974 --eval-command COMMAND, -ex COMMAND
3975 Execute a single GDB CLI command. This may be
3976 specified multiple times and in conjunction
3977 with the --command (-x) option.
3979 * Deprecated commands removed
3981 The following commands, that were deprecated in 2000, have been
3985 set|show arm disassembly-flavor set|show arm disassembler
3986 othernames set arm disassembler
3987 set|show remotedebug set|show debug remote
3988 set|show archdebug set|show debug arch
3989 set|show eventdebug set|show debug event
3992 * New BSD user-level threads support
3994 It is now possible to debug programs using the user-level threads
3995 library on OpenBSD and FreeBSD. Currently supported (target)
3998 FreeBSD/amd64 x86_64-*-freebsd*
3999 FreeBSD/i386 i386-*-freebsd*
4000 OpenBSD/i386 i386-*-openbsd*
4002 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4003 are not yet supported.
4005 * New support for Matsushita MN10300 w/sim added
4006 (Work in progress). mn10300-elf.
4008 * REMOVED configurations and files
4010 VxWorks and the XDR protocol *-*-vxworks
4011 Motorola MCORE mcore-*-*
4012 National Semiconductor NS32000 ns32k-*-*
4014 * New "set print array-indexes" command
4016 After turning this setting "on", GDB prints the index of each element
4017 when displaying arrays. The default is "off" to preserve the previous
4020 * VAX floating point support
4022 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4024 * User-defined command support
4026 In addition to using $arg0..$arg9 for argument passing, it is now possible
4027 to use $argc to determine now many arguments have been passed. See the
4028 section on user-defined commands in the user manual for more information.
4030 *** Changes in GDB 6.3:
4032 * New command line option
4034 GDB now accepts -l followed by a number to set the timeout for remote
4037 * GDB works with GCC -feliminate-dwarf2-dups
4039 GDB now supports a more compact representation of DWARF-2 debug
4040 information using DW_FORM_ref_addr references. These are produced
4041 by GCC with the option -feliminate-dwarf2-dups and also by some
4042 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4043 to use -feliminate-dwarf2-dups.
4045 * Internationalization
4047 When supported by the host system, GDB will be built with
4048 internationalization (libintl). The task of marking up the sources is
4049 continued, we're looking forward to our first translation.
4053 Initial support for debugging programs compiled with the GNAT
4054 implementation of the Ada programming language has been integrated
4055 into GDB. In this release, support is limited to expression evaluation.
4057 * New native configurations
4059 GNU/Linux/m32r m32r-*-linux-gnu
4063 GDB's remote protocol now includes support for the 'p' packet. This
4064 packet is used to fetch individual registers from a remote inferior.
4066 * END-OF-LIFE registers[] compatibility module
4068 GDB's internal register infrastructure has been completely rewritten.
4069 The new infrastructure making possible the implementation of key new
4070 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4073 GDB 6.3 will be the last release to include the the registers[]
4074 compatibility module that allowed out-of-date configurations to
4075 continue to work. This change directly impacts the following
4085 powerpc bdm protocol
4087 Unless there is activity to revive these configurations, they will be
4088 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4090 * OBSOLETE configurations and files
4092 Configurations that have been declared obsolete in this release have
4093 been commented out. Unless there is activity to revive these
4094 configurations, the next release of GDB will have their sources
4095 permanently REMOVED.
4104 *** Changes in GDB 6.2.1:
4106 * MIPS `break main; run' gave an heuristic-fence-post warning
4108 When attempting to run even a simple program, a warning about
4109 heuristic-fence-post being hit would be reported. This problem has
4112 * MIPS IRIX 'long double' crashed GDB
4114 When examining a long double variable, GDB would get a segmentation
4115 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4116 IRIX long double values).
4120 A bug in the VAX stack code was causing problems with the "next"
4121 command. This problem has been fixed.
4123 *** Changes in GDB 6.2:
4125 * Fix for ``many threads''
4127 On GNU/Linux systems that use the NPTL threads library, a program
4128 rapidly creating and deleting threads would confuse GDB leading to the
4131 ptrace: No such process.
4132 thread_db_get_info: cannot get thread info: generic error
4134 This problem has been fixed.
4136 * "-async" and "-noasync" options removed.
4138 Support for the broken "-noasync" option has been removed (it caused
4141 * New ``start'' command.
4143 This command runs the program until the begining of the main procedure.
4145 * New BSD Kernel Data Access Library (libkvm) interface
4147 Using ``target kvm'' it is now possible to debug kernel core dumps and
4148 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4149 platforms. Currently supported (native-only) configurations are:
4151 FreeBSD/amd64 x86_64-*-freebsd*
4152 FreeBSD/i386 i?86-*-freebsd*
4153 NetBSD/i386 i?86-*-netbsd*
4154 NetBSD/m68k m68*-*-netbsd*
4155 NetBSD/sparc sparc-*-netbsd*
4156 OpenBSD/amd64 x86_64-*-openbsd*
4157 OpenBSD/i386 i?86-*-openbsd*
4158 OpenBSD/m68k m68*-openbsd*
4159 OpenBSD/sparc sparc-*-openbsd*
4161 * Signal trampoline code overhauled
4163 Many generic problems with GDB's signal handling code have been fixed.
4164 These include: backtraces through non-contiguous stacks; recognition
4165 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4166 call; backtrace through a signal trampoline; step into and out of
4167 signal handlers; and single-stepping in the signal trampoline.
4169 Please note that kernel bugs are a limiting factor here. These
4170 features have been shown to work on an s390 GNU/Linux system that
4171 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4173 * Cygwin support for DWARF 2 added.
4175 * New native configurations
4177 GNU/Linux/hppa hppa*-*-linux*
4178 OpenBSD/hppa hppa*-*-openbsd*
4179 OpenBSD/m68k m68*-*-openbsd*
4180 OpenBSD/m88k m88*-*-openbsd*
4181 OpenBSD/powerpc powerpc-*-openbsd*
4182 NetBSD/vax vax-*-netbsd*
4183 OpenBSD/vax vax-*-openbsd*
4185 * END-OF-LIFE frame compatibility module
4187 GDB's internal frame infrastructure has been completely rewritten.
4188 The new infrastructure making it possible to support key new features
4189 including DWARF 2 Call Frame Information. To aid in the task of
4190 migrating old configurations to this new infrastructure, a
4191 compatibility module, that allowed old configurations to continue to
4192 work, was also included.
4194 GDB 6.2 will be the last release to include this frame compatibility
4195 module. This change directly impacts the following configurations:
4205 Unless there is activity to revive these configurations, they will be
4206 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4208 * REMOVED configurations and files
4210 Sun 3, running SunOS 3 m68*-*-sunos3*
4211 Sun 3, running SunOS 4 m68*-*-sunos4*
4212 Sun 2, running SunOS 3 m68000-*-sunos3*
4213 Sun 2, running SunOS 4 m68000-*-sunos4*
4214 Motorola 680x0 running LynxOS m68*-*-lynxos*
4215 AT&T 3b1/Unix pc m68*-att-*
4216 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4217 decstation mips-dec-* mips-little-*
4218 riscos mips-*-riscos* mips-*-sysv*
4219 sonymips mips-sony-*
4220 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4222 *** Changes in GDB 6.1.1:
4224 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4226 The TUI (Text-mode User Interface) is now built as part of a default
4227 GDB configuration. It is enabled by either selecting the TUI with the
4228 command line option "-i=tui" or by running the separate "gdbtui"
4229 program. For more information on the TUI, see the manual "Debugging
4232 * Pending breakpoint support (also included in GDB 6.1)
4234 Support has been added to allow you to specify breakpoints in shared
4235 libraries that have not yet been loaded. If a breakpoint location
4236 cannot be found, and the "breakpoint pending" option is set to auto,
4237 GDB queries you if you wish to make the breakpoint pending on a future
4238 shared-library load. If and when GDB resolves the breakpoint symbol,
4239 the pending breakpoint is removed as one or more regular breakpoints
4242 Pending breakpoints are very useful for GCJ Java debugging.
4244 * Fixed ISO-C build problems
4246 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4247 non ISO-C code that stopped them being built using a more strict ISO-C
4248 compiler (e.g., IBM's C compiler).
4250 * Fixed build problem on IRIX 5
4252 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4253 wasn't able to compile compile on an IRIX 5 system.
4255 * Added execute permission to gdb/gdbserver/configure
4257 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4258 permission. This bug would cause configure to fail on a number of
4259 systems (Solaris, IRIX). Ref: server/519.
4261 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4263 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4264 has been updated to use constant array sizes.
4266 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4268 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4269 its generated DWARF Call Frame Info. This encoding was causing GDB to
4270 panic, that panic has been fixed. Ref: gdb/1628.
4272 * Fixed a problem when examining parameters in shared library code.
4274 When examining parameters in optimized shared library code generated
4275 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4276 not available''. GDB now correctly displays the variable's value.
4278 *** Changes in GDB 6.1:
4280 * Removed --with-mmalloc
4282 Support for the mmalloc memory manager has been removed, as it
4283 conflicted with the internal gdb byte cache.
4285 * Changes in AMD64 configurations
4287 The AMD64 target now includes the %cs and %ss registers. As a result
4288 the AMD64 remote protocol has changed; this affects the floating-point
4289 and SSE registers. If you rely on those registers for your debugging,
4290 you should upgrade gdbserver on the remote side.
4292 * Revised SPARC target
4294 The SPARC target has been completely revised, incorporating the
4295 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4296 support for LynxOS and SunOS 4 has been dropped. Calling functions
4297 from within GDB on operating systems with a non-executable stack
4298 (Solaris, OpenBSD) now works.
4302 GDB has a new C++ demangler which does a better job on the mangled
4303 names generated by current versions of g++. It also runs faster, so
4304 with this and other changes gdb should now start faster on large C++
4307 * DWARF 2 Location Expressions
4309 GDB support for location expressions has been extended to support function
4310 arguments and frame bases. Older versions of GDB could crash when they
4313 * C++ nested types and namespaces
4315 GDB's support for nested types and namespaces in C++ has been
4316 improved, especially if you use the DWARF 2 debugging format. (This
4317 is the default for recent versions of GCC on most platforms.)
4318 Specifically, if you have a class "Inner" defined within a class or
4319 namespace "Outer", then GDB realizes that the class's name is
4320 "Outer::Inner", not simply "Inner". This should greatly reduce the
4321 frequency of complaints about not finding RTTI symbols. In addition,
4322 if you are stopped at inside of a function defined within a namespace,
4323 GDB modifies its name lookup accordingly.
4325 * New native configurations
4327 NetBSD/amd64 x86_64-*-netbsd*
4328 OpenBSD/amd64 x86_64-*-openbsd*
4329 OpenBSD/alpha alpha*-*-openbsd*
4330 OpenBSD/sparc sparc-*-openbsd*
4331 OpenBSD/sparc64 sparc64-*-openbsd*
4333 * New debugging protocols
4335 M32R with SDI protocol m32r-*-elf*
4337 * "set prompt-escape-char" command deleted.
4339 The command "set prompt-escape-char" has been deleted. This command,
4340 and its very obscure effet on GDB's prompt, was never documented,
4341 tested, nor mentioned in the NEWS file.
4343 * OBSOLETE configurations and files
4345 Configurations that have been declared obsolete in this release have
4346 been commented out. Unless there is activity to revive these
4347 configurations, the next release of GDB will have their sources
4348 permanently REMOVED.
4350 Sun 3, running SunOS 3 m68*-*-sunos3*
4351 Sun 3, running SunOS 4 m68*-*-sunos4*
4352 Sun 2, running SunOS 3 m68000-*-sunos3*
4353 Sun 2, running SunOS 4 m68000-*-sunos4*
4354 Motorola 680x0 running LynxOS m68*-*-lynxos*
4355 AT&T 3b1/Unix pc m68*-att-*
4356 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4357 decstation mips-dec-* mips-little-*
4358 riscos mips-*-riscos* mips-*-sysv*
4359 sonymips mips-sony-*
4360 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4362 * REMOVED configurations and files
4364 SGI Irix-4.x mips-sgi-irix4 or iris4
4365 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4366 Z8000 simulator z8k-zilog-none or z8ksim
4367 Matsushita MN10200 w/simulator mn10200-*-*
4368 H8/500 simulator h8500-hitachi-hms or h8500hms
4369 HP/PA running BSD hppa*-*-bsd*
4370 HP/PA running OSF/1 hppa*-*-osf*
4371 HP/PA Pro target hppa*-*-pro*
4372 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4373 386BSD i[3456]86-*-bsd*
4374 Sequent family i[3456]86-sequent-sysv4*
4375 i[3456]86-sequent-sysv*
4376 i[3456]86-sequent-bsd*
4377 SPARC running LynxOS sparc-*-lynxos*
4378 SPARC running SunOS 4 sparc-*-sunos4*
4379 Tsqware Sparclet sparclet-*-*
4380 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4382 *** Changes in GDB 6.0:
4386 Support for debugging the Objective-C programming language has been
4387 integrated into GDB.
4389 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4391 DWARF 2's Call Frame Information makes available compiler generated
4392 information that more exactly describes the program's run-time stack.
4393 By using this information, GDB is able to provide more robust stack
4396 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4397 have been updated to use a new backtrace mechanism which includes
4398 DWARF 2 CFI support.
4402 GDB's remote protocol has been extended to include support for hosted
4403 file I/O (where the remote target uses GDB's file system). See GDB's
4404 remote protocol documentation for details.
4406 * All targets using the new architecture framework.
4408 All of GDB's targets have been updated to use the new internal
4409 architecture framework. The way is now open for future GDB releases
4410 to include cross-architecture native debugging support (i386 on amd64,
4413 * GNU/Linux's Thread Local Storage (TLS)
4415 GDB now includes support for for the GNU/Linux implementation of
4416 per-thread variables.
4418 * GNU/Linux's Native POSIX Thread Library (NPTL)
4420 GDB's thread code has been updated to work with either the new
4421 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4423 * Separate debug info.
4425 GDB, in conjunction with BINUTILS, now supports a mechanism for
4426 automatically loading debug information from a separate file. Instead
4427 of shipping full debug and non-debug versions of system libraries,
4428 system integrators can now instead ship just the stripped libraries
4429 and optional debug files.
4431 * DWARF 2 Location Expressions
4433 DWARF 2 Location Expressions allow the compiler to more completely
4434 describe the location of variables (even in optimized code) to the
4437 GDB now includes preliminary support for location expressions (support
4438 for DW_OP_piece is still missing).
4442 A number of long standing bugs that caused GDB to die while starting a
4443 Java application have been fixed. GDB's Java support is now
4444 considered "useable".
4446 * GNU/Linux support for fork, vfork, and exec.
4448 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4449 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4452 * GDB supports logging output to a file
4454 There are two new commands, "set logging" and "show logging", which can be
4455 used to capture GDB's output to a file.
4457 * The meaning of "detach" has changed for gdbserver
4459 The "detach" command will now resume the application, as documented. To
4460 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4463 * d10v, m68hc11 `regs' command deprecated
4465 The `info registers' command has been updated so that it displays the
4466 registers using a format identical to the old `regs' command.
4470 A new command, "maint set profile on/off", has been added. This command can
4471 be used to enable or disable profiling while running GDB, to profile a
4472 session or a set of commands. In addition there is a new configure switch,
4473 "--enable-profiling", which will cause GDB to be compiled with profiling
4474 data, for more informative profiling results.
4476 * Default MI syntax changed to "mi2".
4478 The default MI (machine interface) syntax, enabled by the command line
4479 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4480 "mi1", can be enabled by specifying the option "-i=mi1".
4482 Support for the original "mi0" syntax (included in GDB 5.0) has been
4485 Fix for gdb/192: removed extraneous space when displaying frame level.
4486 Fix for gdb/672: update changelist is now output in mi list format.
4487 Fix for gdb/702: a -var-assign that updates the value now shows up
4488 in a subsequent -var-update.
4490 * New native configurations.
4492 FreeBSD/amd64 x86_64-*-freebsd*
4494 * Multi-arched targets.
4496 HP/PA HPUX11 hppa*-*-hpux*
4497 Renesas M32R/D w/simulator m32r-*-elf*
4499 * OBSOLETE configurations and files
4501 Configurations that have been declared obsolete in this release have
4502 been commented out. Unless there is activity to revive these
4503 configurations, the next release of GDB will have their sources
4504 permanently REMOVED.
4506 Z8000 simulator z8k-zilog-none or z8ksim
4507 Matsushita MN10200 w/simulator mn10200-*-*
4508 H8/500 simulator h8500-hitachi-hms or h8500hms
4509 HP/PA running BSD hppa*-*-bsd*
4510 HP/PA running OSF/1 hppa*-*-osf*
4511 HP/PA Pro target hppa*-*-pro*
4512 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4513 Sequent family i[3456]86-sequent-sysv4*
4514 i[3456]86-sequent-sysv*
4515 i[3456]86-sequent-bsd*
4516 Tsqware Sparclet sparclet-*-*
4517 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4519 * REMOVED configurations and files
4522 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4523 IBM AIX PS/2 i[3456]86-*-aix
4524 i386 running Mach 3.0 i[3456]86-*-mach3*
4525 i386 running Mach i[3456]86-*-mach*
4526 i386 running OSF/1 i[3456]86-*osf1mk*
4527 HP/Apollo 68k Family m68*-apollo*-sysv*,
4529 m68*-hp-bsd*, m68*-hp-hpux*
4530 Argonaut Risc Chip (ARC) arc-*-*
4531 Mitsubishi D30V d30v-*-*
4532 Fujitsu FR30 fr30-*-elf*
4533 OS/9000 i[34]86-*-os9k
4534 I960 with MON960 i960-*-coff
4536 * MIPS $fp behavior changed
4538 The convenience variable $fp, for the MIPS, now consistently returns
4539 the address of the current frame's base. Previously, depending on the
4540 context, $fp could refer to either $sp or the current frame's base
4541 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4542 The GNU Source-Level Debugger''.
4544 *** Changes in GDB 5.3:
4546 * GNU/Linux shared library multi-threaded performance improved.
4548 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4549 `/proc', in preference to `ptrace' for memory reads. This may result
4550 in an improvement in the start-up time of multi-threaded, shared
4551 library applications when run under GDB. One GDB user writes: ``loads
4552 shared libs like mad''.
4554 * ``gdbserver'' now supports multi-threaded applications on some targets
4556 Support for debugging multi-threaded applications which use
4557 the GNU/Linux LinuxThreads package has been added for
4558 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4559 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4561 * GDB now supports C/C++ preprocessor macros.
4563 GDB now expands preprocessor macro invocations in C/C++ expressions,
4564 and provides various commands for showing macro definitions and how
4567 The new command `macro expand EXPRESSION' expands any macro
4568 invocations in expression, and shows the result.
4570 The new command `show macro MACRO-NAME' shows the definition of the
4571 macro named MACRO-NAME, and where it was defined.
4573 Most compilers don't include information about macros in the debugging
4574 information by default. In GCC 3.1, for example, you need to compile
4575 your program with the options `-gdwarf-2 -g3'. If the macro
4576 information is present in the executable, GDB will read it.
4578 * Multi-arched targets.
4580 DEC Alpha (partial) alpha*-*-*
4581 DEC VAX (partial) vax-*-*
4583 National Semiconductor NS32000 (partial) ns32k-*-*
4584 Motorola 68000 (partial) m68k-*-*
4585 Motorola MCORE mcore-*-*
4589 Fujitsu FRV architecture added by Red Hat frv*-*-*
4592 * New native configurations
4594 Alpha NetBSD alpha*-*-netbsd*
4595 SH NetBSD sh*-*-netbsdelf*
4596 MIPS NetBSD mips*-*-netbsd*
4597 UltraSPARC NetBSD sparc64-*-netbsd*
4599 * OBSOLETE configurations and files
4601 Configurations that have been declared obsolete in this release have
4602 been commented out. Unless there is activity to revive these
4603 configurations, the next release of GDB will have their sources
4604 permanently REMOVED.
4606 Mitsubishi D30V d30v-*-*
4607 OS/9000 i[34]86-*-os9k
4608 IBM AIX PS/2 i[3456]86-*-aix
4609 Fujitsu FR30 fr30-*-elf*
4610 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4611 Argonaut Risc Chip (ARC) arc-*-*
4612 i386 running Mach 3.0 i[3456]86-*-mach3*
4613 i386 running Mach i[3456]86-*-mach*
4614 i386 running OSF/1 i[3456]86-*osf1mk*
4615 HP/Apollo 68k Family m68*-apollo*-sysv*,
4617 m68*-hp-bsd*, m68*-hp-hpux*
4618 I960 with MON960 i960-*-coff
4620 * OBSOLETE languages
4622 CHILL, a Pascal like language used by telecommunications companies.
4624 * REMOVED configurations and files
4626 AMD 29k family via UDI a29k-amd-udi, udi29k
4627 A29K VxWorks a29k-*-vxworks
4628 AMD 29000 embedded, using EBMON a29k-none-none
4629 AMD 29000 embedded with COFF a29k-none-coff
4630 AMD 29000 embedded with a.out a29k-none-aout
4632 testsuite/gdb.hp/gdb.threads-hp/ directory
4634 * New command "set max-user-call-depth <nnn>"
4636 This command allows the user to limit the call depth of user-defined
4637 commands. The default is 1024.
4639 * Changes in FreeBSD/i386 native debugging.
4641 Support for the "generate-core-file" has been added.
4643 * New commands "dump", "append", and "restore".
4645 These commands allow data to be copied from target memory
4646 to a bfd-format or binary file (dump and append), and back
4647 from a file into memory (restore).
4649 * Improved "next/step" support on multi-processor Alpha Tru64.
4651 The previous single-step mechanism could cause unpredictable problems,
4652 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4653 of a software single-step mechanism prevents this.
4655 *** Changes in GDB 5.2.1:
4663 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4664 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4665 Fix, by Joel Brobecker imported from mainline.
4667 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4668 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4669 Fix, by Fred Fish, imported from mainline.
4671 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4672 Surprisingly enough, it works now.
4673 By Michal Ludvig, imported from mainline.
4675 i386 hardware watchpoint support:
4676 avoid misses on second run for some targets.
4677 By Pierre Muller, imported from mainline.
4679 *** Changes in GDB 5.2:
4681 * New command "set trust-readonly-sections on[off]".
4683 This command is a hint that tells gdb that read-only sections
4684 really are read-only (ie. that their contents will not change).
4685 In this mode, gdb will go to the object file rather than the
4686 target to read memory from read-only sections (such as ".text").
4687 This can be a significant performance improvement on some
4688 (notably embedded) targets.
4690 * New command "generate-core-file" (or "gcore").
4692 This new gdb command allows the user to drop a core file of the child
4693 process state at any time. So far it's been implemented only for
4694 GNU/Linux and Solaris, but should be relatively easily ported to other
4695 hosts. Argument is core file name (defaults to core.<pid>).
4697 * New command line option
4699 GDB now accepts --pid or -p followed by a process id.
4701 * Change in command line behavior -- corefiles vs. process ids.
4703 There is a subtle behavior in the way in which GDB handles
4704 command line arguments. The first non-flag argument is always
4705 a program to debug, but the second non-flag argument may either
4706 be a corefile or a process id. Previously, GDB would attempt to
4707 open the second argument as a corefile, and if that failed, would
4708 issue a superfluous error message and then attempt to attach it as
4709 a process. Now, if the second argument begins with a non-digit,
4710 it will be treated as a corefile. If it begins with a digit,
4711 GDB will attempt to attach it as a process, and if no such process
4712 is found, will then attempt to open it as a corefile.
4714 * Changes in ARM configurations.
4716 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4717 configuration is fully multi-arch.
4719 * New native configurations
4721 ARM NetBSD arm*-*-netbsd*
4722 x86 OpenBSD i[3456]86-*-openbsd*
4723 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4724 Sparc64 running FreeBSD sparc64-*-freebsd*
4728 Sanyo XStormy16 xstormy16-elf
4730 * OBSOLETE configurations and files
4732 Configurations that have been declared obsolete in this release have
4733 been commented out. Unless there is activity to revive these
4734 configurations, the next release of GDB will have their sources
4735 permanently REMOVED.
4737 AMD 29k family via UDI a29k-amd-udi, udi29k
4738 A29K VxWorks a29k-*-vxworks
4739 AMD 29000 embedded, using EBMON a29k-none-none
4740 AMD 29000 embedded with COFF a29k-none-coff
4741 AMD 29000 embedded with a.out a29k-none-aout
4743 testsuite/gdb.hp/gdb.threads-hp/ directory
4745 * REMOVED configurations and files
4747 TI TMS320C80 tic80-*-*
4749 PowerPC Solaris powerpcle-*-solaris*
4750 PowerPC Windows NT powerpcle-*-cygwin32
4751 PowerPC Netware powerpc-*-netware*
4752 Harris/CXUX m88k m88*-harris-cxux*
4753 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4754 ns32k-utek-sysv* ns32k-utek-*
4755 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4756 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4757 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4758 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4759 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4761 * Changes to command line processing
4763 The new `--args' feature can be used to specify command-line arguments
4764 for the inferior from gdb's command line.
4766 * Changes to key bindings
4768 There is a new `operate-and-get-next' function bound to `C-o'.
4770 *** Changes in GDB 5.1.1
4772 Fix compile problem on DJGPP.
4774 Fix a problem with floating-point registers on the i386 being
4777 Fix to stop GDB crashing on .debug_str debug info.
4779 Numerous documentation fixes.
4781 Numerous testsuite fixes.
4783 *** Changes in GDB 5.1:
4785 * New native configurations
4787 Alpha FreeBSD alpha*-*-freebsd*
4788 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4789 MIPS GNU/Linux mips*-*-linux*
4790 MIPS SGI Irix 6.x mips*-sgi-irix6*
4791 ia64 AIX ia64-*-aix*
4792 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4796 Motorola 68HC11 and 68HC12 m68hc11-elf
4798 UltraSparc running GNU/Linux sparc64-*-linux*
4800 * OBSOLETE configurations and files
4802 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4803 Harris/CXUX m88k m88*-harris-cxux*
4804 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4805 ns32k-utek-sysv* ns32k-utek-*
4806 TI TMS320C80 tic80-*-*
4808 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4809 PowerPC Solaris powerpcle-*-solaris*
4810 PowerPC Windows NT powerpcle-*-cygwin32
4811 PowerPC Netware powerpc-*-netware*
4812 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4813 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4814 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4815 Apple Macintosh (MPW) host N/A
4817 stuff.c (Program to stuff files into a specially prepared space in kdb)
4818 kdb-start.c (Main loop for the standalone kernel debugger)
4820 Configurations that have been declared obsolete in this release have
4821 been commented out. Unless there is activity to revive these
4822 configurations, the next release of GDB will have their sources
4823 permanently REMOVED.
4825 * REMOVED configurations and files
4827 Altos 3068 m68*-altos-*
4828 Convex c1-*-*, c2-*-*
4830 ARM RISCix arm-*-* (as host)
4834 * GDB has been converted to ISO C.
4836 GDB's source code has been converted to ISO C. In particular, the
4837 sources are fully protoized, and rely on standard headers being
4842 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4844 * The MI enabled by default.
4846 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4847 revised and enabled by default. Packages which use GDB as a debugging
4848 engine behind a UI or another front end are encouraged to switch to
4849 using the GDB/MI interface, instead of the old annotations interface
4850 which is now deprecated.
4852 * Support for debugging Pascal programs.
4854 GDB now includes support for debugging Pascal programs. The following
4855 main features are supported:
4857 - Pascal-specific data types such as sets;
4859 - automatic recognition of Pascal sources based on file-name
4862 - Pascal-style display of data types, variables, and functions;
4864 - a Pascal expression parser.
4866 However, some important features are not yet supported.
4868 - Pascal string operations are not supported at all;
4870 - there are some problems with boolean types;
4872 - Pascal type hexadecimal constants are not supported
4873 because they conflict with the internal variables format;
4875 - support for Pascal objects and classes is not full yet;
4877 - unlike Pascal, GDB is case-sensitive for symbol names.
4879 * Changes in completion.
4881 Commands such as `shell', `run' and `set args', which pass arguments
4882 to inferior programs, now complete on file names, similar to what
4883 users expect at the shell prompt.
4885 Commands which accept locations, such as `disassemble', `print',
4886 `breakpoint', `until', etc. now complete on filenames as well as
4887 program symbols. Thus, if you type "break foob TAB", and the source
4888 files linked into the programs include `foobar.c', that file name will
4889 be one of the candidates for completion. However, file names are not
4890 considered for completion after you typed a colon that delimits a file
4891 name from a name of a function in that file, as in "break foo.c:bar".
4893 `set demangle-style' completes on available demangling styles.
4895 * New platform-independent commands:
4897 It is now possible to define a post-hook for a command as well as a
4898 hook that runs before the command. For more details, see the
4899 documentation of `hookpost' in the GDB manual.
4901 * Changes in GNU/Linux native debugging.
4903 Support for debugging multi-threaded programs has been completely
4904 revised for all platforms except m68k and sparc. You can now debug as
4905 many threads as your system allows you to have.
4907 Attach/detach is supported for multi-threaded programs.
4909 Support for SSE registers was added for x86. This doesn't work for
4910 multi-threaded programs though.
4912 * Changes in MIPS configurations.
4914 Multi-arch support is enabled for all MIPS configurations.
4916 GDB can now be built as native debugger on SGI Irix 6.x systems for
4917 debugging n32 executables. (Debugging 64-bit executables is not yet
4920 * Unified support for hardware watchpoints in all x86 configurations.
4922 Most (if not all) native x86 configurations support hardware-assisted
4923 breakpoints and watchpoints in a unified manner. This support
4924 implements debug register sharing between watchpoints, which allows to
4925 put a virtually infinite number of watchpoints on the same address,
4926 and also supports watching regions up to 16 bytes with several debug
4929 The new maintenance command `maintenance show-debug-regs' toggles
4930 debugging print-outs in functions that insert, remove, and test
4931 watchpoints and hardware breakpoints.
4933 * Changes in the DJGPP native configuration.
4935 New command ``info dos sysinfo'' displays assorted information about
4936 the CPU, OS, memory, and DPMI server.
4938 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4939 display information about segment descriptors stored in GDT, LDT, and
4942 New commands ``info dos pde'' and ``info dos pte'' display entries
4943 from Page Directory and Page Tables (for now works with CWSDPMI only).
4944 New command ``info dos address-pte'' displays the Page Table entry for
4945 a given linear address.
4947 GDB can now pass command lines longer than 126 characters to the
4948 program being debugged (requires an update to the libdbg.a library
4949 which is part of the DJGPP development kit).
4951 DWARF2 debug info is now supported.
4953 It is now possible to `step' and `next' through calls to `longjmp'.
4955 * Changes in documentation.
4957 All GDB documentation was converted to GFDL, the GNU Free
4958 Documentation License.
4960 Tracepoints-related commands are now fully documented in the GDB
4963 TUI, the Text-mode User Interface, is now documented in the manual.
4965 Tracepoints-related commands are now fully documented in the GDB
4968 The "GDB Internals" manual now has an index. It also includes
4969 documentation of `ui_out' functions, GDB coding standards, x86
4970 hardware watchpoints, and memory region attributes.
4972 * GDB's version number moved to ``version.in''
4974 The Makefile variable VERSION has been replaced by the file
4975 ``version.in''. People creating GDB distributions should update the
4976 contents of this file.
4980 GUD support is now a standard part of the EMACS distribution.
4982 *** Changes in GDB 5.0:
4984 * Improved support for debugging FP programs on x86 targets
4986 Unified and much-improved support for debugging floating-point
4987 programs on all x86 targets. In particular, ``info float'' now
4988 displays the FP registers in the same format on all x86 targets, with
4989 greater level of detail.
4991 * Improvements and bugfixes in hardware-assisted watchpoints
4993 It is now possible to watch array elements, struct members, and
4994 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4995 on x86 targets no longer erroneously trigger when the address is
4998 * Improvements in the native DJGPP version of GDB
5000 The distribution now includes all the scripts and auxiliary files
5001 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5002 machines ``out of the box''.
5004 The DJGPP version can now debug programs that use signals. It is
5005 possible to catch signals that happened in the debuggee, deliver
5006 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5007 would kill the program being debugged.) Programs that hook hardware
5008 interrupts (keyboard, timer, etc.) can also be debugged.
5010 It is now possible to debug DJGPP programs that redirect their
5011 standard handles or switch them to raw (as opposed to cooked) mode, or
5012 even close them. The command ``run < foo > bar'' works as expected,
5013 and ``info terminal'' reports useful information about the debuggee's
5014 terminal, including raw/cooked mode, redirection, etc.
5016 The DJGPP version now uses termios functions for console I/O, which
5017 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5020 DOS-style file names with drive letters are now fully supported by
5023 It is now possible to debug DJGPP programs that switch their working
5024 directory. It is also possible to rerun the debuggee any number of
5025 times without restarting GDB; thus, you can use the same setup,
5026 breakpoints, etc. for many debugging sessions.
5028 * New native configurations
5030 ARM GNU/Linux arm*-*-linux*
5031 PowerPC GNU/Linux powerpc-*-linux*
5035 Motorola MCore mcore-*-*
5036 x86 VxWorks i[3456]86-*-vxworks*
5037 PowerPC VxWorks powerpc-*-vxworks*
5038 TI TMS320C80 tic80-*-*
5040 * OBSOLETE configurations
5042 Altos 3068 m68*-altos-*
5043 Convex c1-*-*, c2-*-*
5045 ARM RISCix arm-*-* (as host)
5048 Configurations that have been declared obsolete will be commented out,
5049 but the code will be left in place. If there is no activity to revive
5050 these configurations before the next release of GDB, the sources will
5051 be permanently REMOVED.
5053 * Gould support removed
5055 Support for the Gould PowerNode and NP1 has been removed.
5057 * New features for SVR4
5059 On SVR4 native platforms (such as Solaris), if you attach to a process
5060 without first loading a symbol file, GDB will now attempt to locate and
5061 load symbols from the running process's executable file.
5063 * Many C++ enhancements
5065 C++ support has been greatly improved. Overload resolution now works properly
5066 in almost all cases. RTTI support is on the way.
5068 * Remote targets can connect to a sub-program
5070 A popen(3) style serial-device has been added. This device starts a
5071 sub-process (such as a stand-alone simulator) and then communicates
5072 with that. The sub-program to run is specified using the syntax
5073 ``|<program> <args>'' vis:
5075 (gdb) set remotedebug 1
5076 (gdb) target extended-remote |mn10300-elf-sim program-args
5078 * MIPS 64 remote protocol
5080 A long standing bug in the mips64 remote protocol where by GDB
5081 expected certain 32 bit registers (ex SR) to be transfered as 32
5082 instead of 64 bits has been fixed.
5084 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5085 added to provide backward compatibility with older versions of GDB.
5087 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5089 The command ``set remotebinarydownload'' command has been replaced by
5090 ``set remote X-packet''. Other commands in ``set remote'' family
5091 include ``set remote P-packet''.
5093 * Breakpoint commands accept ranges.
5095 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5096 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5097 ``tracepoint passcount'' also accepts a range of tracepoints.
5099 * ``apropos'' command added.
5101 The ``apropos'' command searches through command names and
5102 documentation strings, printing out matches, making it much easier to
5103 try to find a command that does what you are looking for.
5107 A new machine oriented interface (MI) has been added to GDB. This
5108 interface is designed for debug environments running GDB as a separate
5109 process. This is part of the long term libGDB project. See the
5110 "GDB/MI" chapter of the GDB manual for further information. It can be
5111 enabled by configuring with:
5113 .../configure --enable-gdbmi
5115 *** Changes in GDB-4.18:
5117 * New native configurations
5119 HP-UX 10.20 hppa*-*-hpux10.20
5120 HP-UX 11.x hppa*-*-hpux11.0*
5121 M68K GNU/Linux m68*-*-linux*
5125 Fujitsu FR30 fr30-*-elf*
5126 Intel StrongARM strongarm-*-*
5127 Mitsubishi D30V d30v-*-*
5129 * OBSOLETE configurations
5131 Gould PowerNode, NP1 np1-*-*, pn-*-*
5133 Configurations that have been declared obsolete will be commented out,
5134 but the code will be left in place. If there is no activity to revive
5135 these configurations before the next release of GDB, the sources will
5136 be permanently REMOVED.
5140 As a compatibility experiment, GDB's source files buildsym.h and
5141 buildsym.c have been converted to pure standard C, no longer
5142 containing any K&R compatibility code. We believe that all systems in
5143 use today either come with a standard C compiler, or have a GCC port
5144 available. If this is not true, please report the affected
5145 configuration to bug-gdb@gnu.org immediately. See the README file for
5146 information about getting a standard C compiler if you don't have one
5151 GDB now uses readline 2.2.
5153 * set extension-language
5155 You can now control the mapping between filename extensions and source
5156 languages by using the `set extension-language' command. For instance,
5157 you can ask GDB to treat .c files as C++ by saying
5158 set extension-language .c c++
5159 The command `info extensions' lists all of the recognized extensions
5160 and their associated languages.
5162 * Setting processor type for PowerPC and RS/6000
5164 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5165 you can use the `set processor' command to specify what variant of the
5166 PowerPC family you are debugging. The command
5170 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5171 following PowerPC and RS6000 variants:
5173 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5174 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5176 403GC IBM PowerPC 403GC
5177 505 Motorola PowerPC 505
5178 860 Motorola PowerPC 860 or 850
5179 601 Motorola PowerPC 601
5180 602 Motorola PowerPC 602
5181 603 Motorola/IBM PowerPC 603 or 603e
5182 604 Motorola PowerPC 604 or 604e
5183 750 Motorola/IBM PowerPC 750 or 750
5185 At the moment, this command just tells GDB what to name the
5186 special-purpose processor registers. Since almost all the affected
5187 registers are inaccessible to user-level programs, this command is
5188 only useful for remote debugging in its present form.
5192 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5193 more extensive support for HP-UX. Added features include shared
5194 library support, kernel threads and hardware watchpoints for 11.00,
5195 support for HP's ANSI C and C++ compilers, and a compatibility mode
5196 for xdb and dbx commands.
5200 HP's donation includes the new concept of catchpoints, which is a
5201 generalization of the old catch command. On HP-UX, it is now possible
5202 to catch exec, fork, and vfork, as well as library loading.
5204 This means that the existing catch command has changed; its first
5205 argument now specifies the type of catch to be set up. See the
5206 output of "help catch" for a list of catchpoint types.
5208 * Debugging across forks
5210 On HP-UX, you can choose which process to debug when a fork() happens
5215 HP has donated a curses-based terminal user interface (TUI). To get
5216 it, build with --enable-tui. Although this can be enabled for any
5217 configuration, at present it only works for native HP debugging.
5219 * GDB remote protocol additions
5221 A new protocol packet 'X' that writes binary data is now available.
5222 Default behavior is to try 'X', then drop back to 'M' if the stub
5223 fails to respond. The settable variable `remotebinarydownload'
5224 allows explicit control over the use of 'X'.
5226 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5227 full 64-bit address. The command
5229 set remoteaddresssize 32
5231 can be used to revert to the old behaviour. For existing remote stubs
5232 the change should not be noticed, as the additional address information
5235 In order to assist in debugging stubs, you may use the maintenance
5236 command `packet' to send any text string to the stub. For instance,
5238 maint packet heythere
5240 sends the packet "$heythere#<checksum>". Note that it is very easy to
5241 disrupt a debugging session by sending the wrong packet at the wrong
5244 The compare-sections command allows you to compare section data on the
5245 target to what is in the executable file without uploading or
5246 downloading, by comparing CRC checksums.
5248 * Tracing can collect general expressions
5250 You may now collect general expressions at tracepoints. This requires
5251 further additions to the target-side stub; see tracepoint.c and
5252 doc/agentexpr.texi for further details.
5254 * mask-address variable for Mips
5256 For Mips targets, you may control the zeroing of the upper 32 bits of
5257 a 64-bit address by entering `set mask-address on'. This is mainly
5258 of interest to users of embedded R4xxx and R5xxx processors.
5260 * Higher serial baud rates
5262 GDB's serial code now allows you to specify baud rates 57600, 115200,
5263 230400, and 460800 baud. (Note that your host system may not be able
5264 to achieve all of these rates.)
5268 The i960 configuration now includes an initial implementation of a
5269 builtin simulator, contributed by Jim Wilson.
5272 *** Changes in GDB-4.17:
5274 * New native configurations
5276 Alpha GNU/Linux alpha*-*-linux*
5277 Unixware 2.x i[3456]86-unixware2*
5278 Irix 6.x mips*-sgi-irix6*
5279 PowerPC GNU/Linux powerpc-*-linux*
5280 PowerPC Solaris powerpcle-*-solaris*
5281 Sparc GNU/Linux sparc-*-linux*
5282 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5286 Argonaut Risc Chip (ARC) arc-*-*
5287 Hitachi H8/300S h8300*-*-*
5288 Matsushita MN10200 w/simulator mn10200-*-*
5289 Matsushita MN10300 w/simulator mn10300-*-*
5290 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5291 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5292 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5293 Mitsubishi D10V w/simulator d10v-*-*
5294 Mitsubishi M32R/D w/simulator m32r-*-elf*
5295 Tsqware Sparclet sparclet-*-*
5296 NEC V850 w/simulator v850-*-*
5298 * New debugging protocols
5300 ARM with RDI protocol arm*-*-*
5301 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5302 DDB and LSI variants of PMON protocol mips*-*-*
5303 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5304 PowerPC with SDS protocol powerpc{,le}-*-eabi
5305 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5309 All configurations can now understand and use the DWARF 2 debugging
5310 format. The choice is automatic, if the symbol file contains DWARF 2
5315 GDB now includes basic Java language support. This support is
5316 only useful with Java compilers that produce native machine code.
5318 * solib-absolute-prefix and solib-search-path
5320 For SunOS and SVR4 shared libraries, you may now set the prefix for
5321 loading absolute shared library symbol files, and the search path for
5322 locating non-absolute shared library symbol files.
5324 * Live range splitting
5326 GDB can now effectively debug code for which GCC has performed live
5327 range splitting as part of its optimization. See gdb/doc/LRS for
5328 more details on the expected format of the stabs information.
5332 GDB's support for the GNU Hurd, including thread debugging, has been
5333 updated to work with current versions of the Hurd.
5337 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5338 instruction set. ARM GDB automatically detects when Thumb
5339 instructions are in use, and adjusts disassembly and backtracing
5344 GDB's MIPS target configurations now handle the MIP16 16-bit
5349 GDB now includes support for overlays; if an executable has been
5350 linked such that multiple sections are based at the same address, GDB
5351 will decide which section to use for symbolic info. You can choose to
5352 control the decision manually, using overlay commands, or implement
5353 additional target-side support and use "overlay load-target" to bring
5354 in the overlay mapping. Do "help overlay" for more detail.
5358 The command "info symbol <address>" displays information about
5359 the symbol at the specified address.
5363 The standard remote protocol now includes an extension that allows
5364 asynchronous collection and display of trace data. This requires
5365 extensive support in the target-side debugging stub. Tracing mode
5366 includes a new interaction mode in GDB and new commands: see the
5367 file tracepoint.c for more details.
5371 Configurations for embedded MIPS now include a simulator contributed
5372 by Cygnus Solutions. The simulator supports the instruction sets
5373 of most MIPS variants.
5377 Sparc configurations may now include the ERC32 simulator contributed
5378 by the European Space Agency. The simulator is not built into
5379 Sparc targets by default; configure with --enable-sim to include it.
5383 For target configurations that may include multiple variants of a
5384 basic architecture (such as MIPS and SH), you may now set the
5385 architecture explicitly. "set arch" sets, "info arch" lists
5386 the possible architectures.
5388 *** Changes in GDB-4.16:
5390 * New native configurations
5392 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5393 M68K NetBSD m68k-*-netbsd*
5394 PowerPC AIX 4.x powerpc-*-aix*
5395 PowerPC MacOS powerpc-*-macos*
5396 PowerPC Windows NT powerpcle-*-cygwin32
5397 RS/6000 AIX 4.x rs6000-*-aix4*
5401 ARM with RDP protocol arm-*-*
5402 I960 with MON960 i960-*-coff
5403 MIPS VxWorks mips*-*-vxworks*
5404 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5405 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5407 Matra Sparclet sparclet-*-*
5411 The powerpc-eabi configuration now includes the PSIM simulator,
5412 contributed by Andrew Cagney, with assistance from Mike Meissner.
5413 PSIM is a very elaborate model of the PowerPC, including not only
5414 basic instruction set execution, but also details of execution unit
5415 performance and I/O hardware. See sim/ppc/README for more details.
5419 GDB now works with Solaris 2.5.
5421 * Windows 95/NT native
5423 GDB will now work as a native debugger on Windows 95 and Windows NT.
5424 To build it from source, you must use the "gnu-win32" environment,
5425 which uses a DLL to emulate enough of Unix to run the GNU tools.
5426 Further information, binaries, and sources are available at
5427 ftp.cygnus.com, under pub/gnu-win32.
5429 * dont-repeat command
5431 If a user-defined command includes the command `dont-repeat', then the
5432 command will not be repeated if the user just types return. This is
5433 useful if the command is time-consuming to run, so that accidental
5434 extra keystrokes don't run the same command many times.
5436 * Send break instead of ^C
5438 The standard remote protocol now includes an option to send a break
5439 rather than a ^C to the target in order to interrupt it. By default,
5440 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5442 * Remote protocol timeout
5444 The standard remote protocol includes a new variable `remotetimeout'
5445 that allows you to set the number of seconds before GDB gives up trying
5446 to read from the target. The default value is 2.
5448 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5450 By default GDB will automatically keep track of objects as they are
5451 loaded and unloaded by the dynamic linker. By using the command `set
5452 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5453 when shared library events occur, thus allowing you to set breakpoints
5454 in shared libraries which are explicitly loaded by the inferior.
5456 Note this feature does not work on hpux8. On hpux9 you must link
5457 /usr/lib/end.o into your program. This feature should work
5458 automatically on hpux10.
5460 * Irix 5.x hardware watchpoint support
5462 Irix 5 configurations now support the use of hardware watchpoints.
5464 * Mips protocol "SYN garbage limit"
5466 When debugging a Mips target using the `target mips' protocol, you
5467 may set the number of characters that GDB will ignore by setting
5468 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5469 every character. The default value is 1050.
5471 * Recording and replaying remote debug sessions
5473 If you set `remotelogfile' to the name of a file, gdb will write to it
5474 a recording of a remote debug session. This recording may then be
5475 replayed back to gdb using "gdbreplay". See gdbserver/README for
5476 details. This is useful when you have a problem with GDB while doing
5477 remote debugging; you can make a recording of the session and send it
5478 to someone else, who can then recreate the problem.
5480 * Speedups for remote debugging
5482 GDB includes speedups for downloading and stepping MIPS systems using
5483 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5484 and more efficient S-record downloading.
5486 * Memory use reductions and statistics collection
5488 GDB now uses less memory and reports statistics about memory usage.
5489 Try the `maint print statistics' command, for example.
5491 *** Changes in GDB-4.15:
5493 * Psymtabs for XCOFF
5495 The symbol reader for AIX GDB now uses partial symbol tables. This
5496 can greatly improve startup time, especially for large executables.
5498 * Remote targets use caching
5500 Remote targets now use a data cache to speed up communication with the
5501 remote side. The data cache could lead to incorrect results because
5502 it doesn't know about volatile variables, thus making it impossible to
5503 debug targets which use memory mapped I/O devices. `set remotecache
5504 off' turns the the data cache off.
5506 * Remote targets may have threads
5508 The standard remote protocol now includes support for multiple threads
5509 in the target system, using new protocol commands 'H' and 'T'. See
5510 gdb/remote.c for details.
5514 If GDB is configured with `--enable-netrom', then it will include
5515 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5516 acts as though it is a bank of ROM on the target board, but you can
5517 write into it over the network. GDB's support consists only of
5518 support for fast loading into the emulated ROM; to debug, you must use
5519 another protocol, such as standard remote protocol. The usual
5520 sequence is something like
5522 target nrom <netrom-hostname>
5524 target remote <netrom-hostname>:1235
5528 GDB now includes support for the Apple Macintosh, as a host only. It
5529 may be run as either an MPW tool or as a standalone application, and
5530 it can debug through the serial port. All the usual GDB commands are
5531 available, but to the target command, you must supply "serial" as the
5532 device type instead of "/dev/ttyXX". See mpw-README in the main
5533 directory for more information on how to build. The MPW configuration
5534 scripts */mpw-config.in support only a few targets, and only the
5535 mips-idt-ecoff target has been tested.
5539 GDB configuration now uses autoconf. This is not user-visible,
5540 but does simplify configuration and building.
5544 GDB now supports hpux10.
5546 *** Changes in GDB-4.14:
5548 * New native configurations
5550 x86 FreeBSD i[345]86-*-freebsd
5551 x86 NetBSD i[345]86-*-netbsd
5552 NS32k NetBSD ns32k-*-netbsd
5553 Sparc NetBSD sparc-*-netbsd
5557 A29K VxWorks a29k-*-vxworks
5558 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5559 CPU32 EST-300 emulator m68*-*-est*
5560 PowerPC ELF powerpc-*-elf
5563 * Alpha OSF/1 support for procfs
5565 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5566 possible to attach to running processes. As the mounting of the /proc
5567 filesystem is optional on the Alpha, GDB automatically determines
5568 the availability of /proc during startup. This can lead to problems
5569 if /proc is unmounted after GDB has been started.
5571 * Arguments to user-defined commands
5573 User commands may accept up to 10 arguments separated by whitespace.
5574 Arguments are accessed within the user command via $arg0..$arg9. A
5577 print $arg0 + $arg1 + $arg2
5579 To execute the command use:
5582 Defines the command "adder" which prints the sum of its three arguments.
5583 Note the arguments are text substitutions, so they may reference variables,
5584 use complex expressions, or even perform inferior function calls.
5586 * New `if' and `while' commands
5588 This makes it possible to write more sophisticated user-defined
5589 commands. Both commands take a single argument, which is the
5590 expression to evaluate, and must be followed by the commands to
5591 execute, one per line, if the expression is nonzero, the list being
5592 terminated by the word `end'. The `if' command list may include an
5593 `else' word, which causes the following commands to be executed only
5594 if the expression is zero.
5596 * Fortran source language mode
5598 GDB now includes partial support for Fortran 77. It will recognize
5599 Fortran programs and can evaluate a subset of Fortran expressions, but
5600 variables and functions may not be handled correctly. GDB will work
5601 with G77, but does not yet know much about symbols emitted by other
5604 * Better HPUX support
5606 Most debugging facilities now work on dynamic executables for HPPAs
5607 running hpux9 or later. You can attach to running dynamically linked
5608 processes, but by default the dynamic libraries will be read-only, so
5609 for instance you won't be able to put breakpoints in them. To change
5610 that behavior do the following before running the program:
5616 This will cause the libraries to be mapped private and read-write.
5617 To revert to the normal behavior, do this:
5623 You cannot set breakpoints or examine data in the library until after
5624 the library is loaded if the function/data symbols do not have
5627 GDB can now also read debug symbols produced by the HP C compiler on
5628 HPPAs (sorry, no C++, Fortran or 68k support).
5630 * Target byte order now dynamically selectable
5632 You can choose which byte order to use with a target system, via the
5633 commands "set endian big" and "set endian little", and you can see the
5634 current setting by using "show endian". You can also give the command
5635 "set endian auto", in which case GDB will use the byte order
5636 associated with the executable. Currently, only embedded MIPS
5637 configurations support dynamic selection of target byte order.
5639 * New DOS host serial code
5641 This version uses DPMI interrupts to handle buffered I/O, so you
5642 no longer need to run asynctsr when debugging boards connected to
5645 *** Changes in GDB-4.13:
5647 * New "complete" command
5649 This lists all the possible completions for the rest of the line, if it
5650 were to be given as a command itself. This is intended for use by emacs.
5652 * Trailing space optional in prompt
5654 "set prompt" no longer adds a space for you after the prompt you set. This
5655 allows you to set a prompt which ends in a space or one that does not.
5657 * Breakpoint hit counts
5659 "info break" now displays a count of the number of times the breakpoint
5660 has been hit. This is especially useful in conjunction with "ignore"; you
5661 can ignore a large number of breakpoint hits, look at the breakpoint info
5662 to see how many times the breakpoint was hit, then run again, ignoring one
5663 less than that number, and this will get you quickly to the last hit of
5666 * Ability to stop printing at NULL character
5668 "set print null-stop" will cause GDB to stop printing the characters of
5669 an array when the first NULL is encountered. This is useful when large
5670 arrays actually contain only short strings.
5672 * Shared library breakpoints
5674 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5675 breakpoints in shared libraries before the executable is run.
5677 * Hardware watchpoints
5679 There is a new hardware breakpoint for the watch command for sparclite
5680 targets. See gdb/sparclite/hw_breakpoint.note.
5682 Hardware watchpoints are also now supported under GNU/Linux.
5686 Annotations have been added. These are for use with graphical interfaces,
5687 and are still experimental. Currently only gdba.el uses these.
5689 * Improved Irix 5 support
5691 GDB now works properly with Irix 5.2.
5693 * Improved HPPA support
5695 GDB now works properly with the latest GCC and GAS.
5697 * New native configurations
5699 Sequent PTX4 i[34]86-sequent-ptx4
5700 HPPA running OSF/1 hppa*-*-osf*
5701 Atari TT running SVR4 m68*-*-sysv4*
5702 RS/6000 LynxOS rs6000-*-lynxos*
5706 OS/9000 i[34]86-*-os9k
5707 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5710 * Hitachi SH7000 and E7000-PC ICE support
5712 There is now support for communicating with the Hitachi E7000-PC ICE.
5713 This is available automatically when GDB is configured for the SH.
5717 As usual, a variety of small fixes and improvements, both generic
5718 and configuration-specific. See the ChangeLog for more detail.
5720 *** Changes in GDB-4.12:
5722 * Irix 5 is now supported
5726 GDB-4.12 on the HPPA has a number of changes which make it unable
5727 to debug the output from the currently released versions of GCC and
5728 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5729 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5730 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5733 *** Changes in GDB-4.11:
5735 * User visible changes:
5739 The "set remotedebug" option is now consistent between the mips remote
5740 target, remote targets using the gdb-specific protocol, UDI (AMD's
5741 debug protocol for the 29k) and the 88k bug monitor. It is now an
5742 integer specifying a debug level (normally 0 or 1, but 2 means more
5743 debugging info for the mips target).
5745 * DEC Alpha native support
5747 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5748 debug info, but GDB works fairly well with the DEC compiler and should
5749 work with a future GCC release. See the README file for a few
5750 Alpha-specific notes.
5752 * Preliminary thread implementation
5754 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5756 * LynxOS native and target support for 386
5758 This release has been hosted on LynxOS 2.2, and also can be configured
5759 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5762 * Improvements in C++ mangling/demangling.
5764 This release has much better g++ debugging, specifically in name
5765 mangling/demangling, virtual function calls, print virtual table,
5766 call methods, ...etc.
5768 *** Changes in GDB-4.10:
5770 * User visible changes:
5772 Remote debugging using the GDB-specific (`target remote') protocol now
5773 supports the `load' command. This is only useful if you have some
5774 other way of getting the stub to the target system, and you can put it
5775 somewhere in memory where it won't get clobbered by the download.
5777 Filename completion now works.
5779 When run under emacs mode, the "info line" command now causes the
5780 arrow to point to the line specified. Also, "info line" prints
5781 addresses in symbolic form (as well as hex).
5783 All vxworks based targets now support a user settable option, called
5784 vxworks-timeout. This option represents the number of seconds gdb
5785 should wait for responses to rpc's. You might want to use this if
5786 your vxworks target is, perhaps, a slow software simulator or happens
5787 to be on the far side of a thin network line.
5791 This release contains support for using a DEC alpha as a GDB host for
5792 cross debugging. Native alpha debugging is not supported yet.
5795 *** Changes in GDB-4.9:
5799 This is the first GDB release which is accompanied by a matching testsuite.
5800 The testsuite requires installation of dejagnu, which should be available
5801 via ftp from most sites that carry GNU software.
5805 'Cfront' style demangling has had its name changed to 'ARM' style, to
5806 emphasize that it was written from the specifications in the C++ Annotated
5807 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5808 disclaimers, it still generated too much confusion with users attempting to
5809 use gdb with AT&T cfront.
5813 GDB now uses a standard remote interface to a simulator library.
5814 So far, the library contains simulators for the Zilog Z8001/2, the
5815 Hitachi H8/300, H8/500 and Super-H.
5817 * New targets supported
5819 H8/300 simulator h8300-hitachi-hms or h8300hms
5820 H8/500 simulator h8500-hitachi-hms or h8500hms
5821 SH simulator sh-hitachi-hms or sh
5822 Z8000 simulator z8k-zilog-none or z8ksim
5823 IDT MIPS board over serial line mips-idt-ecoff
5825 Cross-debugging to GO32 targets is supported. It requires a custom
5826 version of the i386-stub.c module which is integrated with the
5827 GO32 memory extender.
5829 * New remote protocols
5831 MIPS remote debugging protocol.
5833 * New source languages supported
5835 This version includes preliminary support for Chill, a Pascal like language
5836 used by telecommunications companies. Chill support is also being integrated
5837 into the GNU compiler, but we don't know when it will be publically available.
5840 *** Changes in GDB-4.8:
5842 * HP Precision Architecture supported
5844 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5845 version of this support was available as a set of patches from the
5846 University of Utah. GDB does not support debugging of programs
5847 compiled with the HP compiler, because HP will not document their file
5848 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5849 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5851 Many problems in the preliminary version have been fixed.
5853 * Faster and better demangling
5855 We have improved template demangling and fixed numerous bugs in the GNU style
5856 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5857 character types (wchar_t) are now supported. Demangling of each symbol is now
5858 only done once, and is cached when the symbol table for a file is read in.
5859 This results in a small increase in memory usage for C programs, a moderate
5860 increase in memory usage for C++ programs, and a fantastic speedup in
5863 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5864 from the specifications in the Annotated Reference Manual, which AT&T's
5865 compiler does not actually implement.
5867 * G++ multiple inheritance compiler problem
5869 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5870 inheritance lattices was reworked to properly discover ambiguities. We
5871 recently found an example which causes this new algorithm to fail in a
5872 very subtle way, producing bad debug information for those classes.
5873 The file 'gcc.patch' (in this directory) can be applied to gcc to
5874 circumvent the problem. A future GCC release will contain a complete
5877 The previous G++ debug info problem (mentioned below for the gdb-4.7
5878 release) is fixed in gcc version 2.3.2.
5880 * Improved configure script
5882 The `configure' script will now attempt to guess your system type if
5883 you don't supply a host system type. The old scheme of supplying a
5884 host system triplet is preferable over using this. All the magic is
5885 done in the new `config.guess' script. Examine it for details.
5887 We have also brought our configure script much more in line with the FSF's
5888 version. It now supports the --with-xxx options. In particular,
5889 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5890 The resulting GDB will not be able to read arbitrary object file formats --
5891 only the format ``expected'' to be used on the configured target system.
5892 We hope to make this the default in a future release.
5894 * Documentation improvements
5896 There's new internal documentation on how to modify GDB, and how to
5897 produce clean changes to the code. We implore people to read it
5898 before submitting changes.
5900 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5901 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5902 `info' files are also provided. To build `info' files from scratch,
5903 you will need the latest `makeinfo' release, which will be available in
5904 a future texinfo-X.Y release.
5906 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5907 We're not sure exactly which versions have this problem, but it has
5908 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5909 or better. If that isn't possible, there is a patch in
5910 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5911 around this problem.
5915 GDB now supports array constants that can be used in expressions typed in by
5916 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5917 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5920 The new directory `gdb/sparclite' contains a program that demonstrates
5921 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5923 * New native hosts supported
5925 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5926 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5928 * New targets supported
5930 AMD 29k family via UDI a29k-amd-udi or udi29k
5932 * New file formats supported
5934 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5935 HPUX core files, and SCO 3.2v2 core files.
5939 Attaching to processes now works again; thanks for the many bug reports.
5941 We have also stomped on a bunch of core dumps caused by
5942 printf_filtered("%s") problems.
5944 We eliminated a copyright problem on the rpc and ptrace header files
5945 for VxWorks, which was discovered at the last minute during the 4.7
5946 release. You should now be able to build a VxWorks GDB.
5948 You can now interrupt gdb while an attached process is running. This
5949 will cause the attached process to stop, and give control back to GDB.
5951 We fixed problems caused by using too many file descriptors
5952 for reading symbols from object files and libraries. This was
5953 especially a problem for programs that used many (~100) shared
5956 The `step' command now only enters a subroutine if there is line number
5957 information for the subroutine. Otherwise it acts like the `next'
5958 command. Previously, `step' would enter subroutines if there was
5959 any debugging information about the routine. This avoids problems
5960 when using `cc -g1' on MIPS machines.
5962 * Internal improvements
5964 GDB's internal interfaces have been improved to make it easier to support
5965 debugging of multiple languages in the future.
5967 GDB now uses a common structure for symbol information internally.
5968 Minimal symbols (derived from linkage symbols in object files), partial
5969 symbols (from a quick scan of debug information), and full symbols
5970 contain a common subset of information, making it easier to write
5971 shared code that handles any of them.
5973 * New command line options
5975 We now accept --silent as an alias for --quiet.
5979 The memory-mapped-malloc library is now licensed under the GNU Library
5980 General Public License.
5982 *** Changes in GDB-4.7:
5984 * Host/native/target split
5986 GDB has had some major internal surgery to untangle the support for
5987 hosts and remote targets. Now, when you configure GDB for a remote
5988 target, it will no longer load in all of the support for debugging
5989 local programs on the host. When fully completed and tested, this will
5990 ensure that arbitrary host/target combinations are possible.
5992 The primary conceptual shift is to separate the non-portable code in
5993 GDB into three categories. Host specific code is required any time GDB
5994 is compiled on that host, regardless of the target. Target specific
5995 code relates to the peculiarities of the target, but can be compiled on
5996 any host. Native specific code is everything else: it can only be
5997 built when the host and target are the same system. Child process
5998 handling and core file support are two common `native' examples.
6000 GDB's use of /proc for controlling Unix child processes is now cleaner.
6001 It has been split out into a single module under the `target_ops' vector,
6002 plus two native-dependent functions for each system that uses /proc.
6004 * New hosts supported
6006 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6007 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6008 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6010 * New targets supported
6012 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6013 68030 and CPU32 m68030-*-*, m68332-*-*
6015 * New native hosts supported
6017 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6018 (386bsd is not well tested yet)
6019 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6021 * New file formats supported
6023 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6024 supports reading of `a.out.adobe' object files, which are an a.out
6025 format extended with minimal information about multiple sections.
6029 `show copying' is the same as the old `info copying'.
6030 `show warranty' is the same as `info warrantee'.
6031 These were renamed for consistency. The old commands continue to work.
6033 `info handle' is a new alias for `info signals'.
6035 You can now define pre-command hooks, which attach arbitrary command
6036 scripts to any command. The commands in the hook will be executed
6037 prior to the user's command. You can also create a hook which will be
6038 executed whenever the program stops. See gdb.texinfo.
6042 We now deal with Cfront style name mangling, and can even extract type
6043 info from mangled symbols. GDB can automatically figure out which
6044 symbol mangling style your C++ compiler uses.
6046 Calling of methods and virtual functions has been improved as well.
6050 The crash that occured when debugging Sun Ansi-C compiled binaries is
6051 fixed. This was due to mishandling of the extra N_SO stabs output
6054 We also finally got Ultrix 4.2 running in house, and fixed core file
6055 support, with help from a dozen people on the net.
6057 John M. Farrell discovered that the reason that single-stepping was so
6058 slow on all of the Mips based platforms (primarily SGI and DEC) was
6059 that we were trying to demangle and lookup a symbol used for internal
6060 purposes on every instruction that was being stepped through. Changing
6061 the name of that symbol so that it couldn't be mistaken for a C++
6062 mangled symbol sped things up a great deal.
6064 Rich Pixley sped up symbol lookups in general by getting much smarter
6065 about when C++ symbol mangling is necessary. This should make symbol
6066 completion (TAB on the command line) much faster. It's not as fast as
6067 we'd like, but it's significantly faster than gdb-4.6.
6071 A new user controllable variable 'call_scratch_address' can
6072 specify the location of a scratch area to be used when GDB
6073 calls a function in the target. This is necessary because the
6074 usual method of putting the scratch area on the stack does not work
6075 in systems that have separate instruction and data spaces.
6077 We integrated changes to support the 29k UDI (Universal Debugger
6078 Interface), but discovered at the last minute that we didn't have all
6079 of the appropriate copyright paperwork. We are working with AMD to
6080 resolve this, and hope to have it available soon.
6084 We have sped up the remote serial line protocol, especially for targets
6085 with lots of registers. It now supports a new `expedited status' ('T')
6086 message which can be used in place of the existing 'S' status message.
6087 This allows the remote stub to send only the registers that GDB
6088 needs to make a quick decision about single-stepping or conditional
6089 breakpoints, eliminating the need to fetch the entire register set for
6090 each instruction being stepped through.
6092 The GDB remote serial protocol now implements a write-through cache for
6093 registers, only re-reading the registers if the target has run.
6095 There is also a new remote serial stub for SPARC processors. You can
6096 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6097 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6098 processor with a serial port.
6102 Configure.in files have become much easier to read and modify. A new
6103 `table driven' format makes it more obvious what configurations are
6104 supported, and what files each one uses.
6108 There is a new opcodes library which will eventually contain all of the
6109 disassembly routines and opcode tables. At present, it only contains
6110 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6111 disassembler (binutils/objdump) to share these routines.
6113 The libiberty library is now copylefted under the GNU Library General
6114 Public License. This allows more liberal use, and was done so libg++
6115 can use it. This makes no difference to GDB, since the Library License
6116 grants all the rights from the General Public License.
6120 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6121 reference to the stabs symbol info used by the debugger. It is (as far
6122 as we know) the only published document on this fascinating topic. We
6123 encourage you to read it, compare it to the stabs information on your
6124 system, and send improvements on the document in general (to
6125 bug-gdb@prep.ai.mit.edu).
6127 And, of course, many bugs have been fixed.
6130 *** Changes in GDB-4.6:
6132 * Better support for C++ function names
6134 GDB now accepts as input the "demangled form" of C++ overloaded function
6135 names and member function names, and can do command completion on such names
6136 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6137 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6138 Make use of command completion, it is your friend.
6140 GDB also now accepts a variety of C++ mangled symbol formats. They are
6141 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6142 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6143 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6144 for the list of formats.
6146 * G++ symbol mangling problem
6148 Recent versions of gcc have a bug in how they emit debugging information for
6149 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6150 directory) can be applied to gcc to fix the problem. Alternatively, if you
6151 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6152 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6153 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6156 * New 'maintenance' command
6158 All of the commands related to hacking GDB internals have been moved out of
6159 the main command set, and now live behind the 'maintenance' command. This
6160 can also be abbreviated as 'mt'. The following changes were made:
6162 dump-me -> maintenance dump-me
6163 info all-breakpoints -> maintenance info breakpoints
6164 printmsyms -> maintenance print msyms
6165 printobjfiles -> maintenance print objfiles
6166 printpsyms -> maintenance print psymbols
6167 printsyms -> maintenance print symbols
6169 The following commands are new:
6171 maintenance demangle Call internal GDB demangler routine to
6172 demangle a C++ link name and prints the result.
6173 maintenance print type Print a type chain for a given symbol
6175 * Change to .gdbinit file processing
6177 We now read the $HOME/.gdbinit file before processing the argv arguments
6178 (e.g. reading symbol files or core files). This allows global parameters to
6179 be set, which will apply during the symbol reading. The ./.gdbinit is still
6180 read after argv processing.
6182 * New hosts supported
6184 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6186 GNU/Linux support i386-unknown-linux or linux
6188 We are also including code to support the HP/PA running BSD and HPUX. This
6189 is almost guaranteed not to work, as we didn't have time to test or build it
6190 for this release. We are including it so that the more adventurous (or
6191 masochistic) of you can play with it. We also had major problems with the
6192 fact that the compiler that we got from HP doesn't support the -g option.
6195 * New targets supported
6197 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6199 * More smarts about finding #include files
6201 GDB now remembers the compilation directory for all include files, and for
6202 all files from which C is generated (like yacc and lex sources). This
6203 greatly improves GDB's ability to find yacc/lex sources, and include files,
6204 especially if you are debugging your program from a directory different from
6205 the one that contains your sources.
6207 We also fixed a bug which caused difficulty with listing and setting
6208 breakpoints in include files which contain C code. (In the past, you had to
6209 try twice in order to list an include file that you hadn't looked at before.)
6211 * Interesting infernals change
6213 GDB now deals with arbitrary numbers of sections, where the symbols for each
6214 section must be relocated relative to that section's landing place in the
6215 target's address space. This work was needed to support ELF with embedded
6216 stabs used by Solaris-2.0.
6218 * Bug fixes (of course!)
6220 There have been loads of fixes for the following things:
6221 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6222 i960, stabs, DOS(GO32), procfs, etc...
6224 See the ChangeLog for details.
6226 *** Changes in GDB-4.5:
6228 * New machines supported (host and target)
6230 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6232 SGI Irix-4.x mips-sgi-irix4 or iris4
6234 * New malloc package
6236 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6237 Mmalloc is capable of handling mutiple heaps of memory. It is also
6238 capable of saving a heap to a file, and then mapping it back in later.
6239 This can be used to greatly speedup the startup of GDB by using a
6240 pre-parsed symbol table which lives in a mmalloc managed heap. For
6241 more details, please read mmalloc/mmalloc.texi.
6245 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6246 'help info proc' for details.
6248 * MIPS ecoff symbol table format
6250 The code that reads MIPS symbol table format is now supported on all hosts.
6251 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6254 * File name changes for MS-DOS
6256 Many files in the config directories have been renamed to make it easier to
6257 support GDB on MS-DOSe systems (which have very restrictive file name
6258 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6259 environment) is close to working but has some remaining problems. Note
6260 that debugging of DOS programs is not supported, due to limitations
6261 in the ``operating system'', but it can be used to host cross-debugging.
6263 * Cross byte order fixes
6265 Many fixes have been made to support cross debugging of Sparc and MIPS
6266 targets from hosts whose byte order differs.
6268 * New -mapped and -readnow options
6270 If memory-mapped files are available on your system through the 'mmap'
6271 system call, you can use the -mapped option on the `file' or
6272 `symbol-file' commands to cause GDB to write the symbols from your
6273 program into a reusable file. If the program you are debugging is
6274 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6275 Future GDB debugging sessions will notice the presence of this file,
6276 and will quickly map in symbol information from it, rather than reading
6277 the symbol table from the executable program. Using the '-mapped'
6278 option in a GDB `file' or `symbol-file' command has the same effect as
6279 starting GDB with the '-mapped' command-line option.
6281 You can cause GDB to read the entire symbol table immediately by using
6282 the '-readnow' option with any of the commands that load symbol table
6283 information (or on the GDB command line). This makes the command
6284 slower, but makes future operations faster.
6286 The -mapped and -readnow options are typically combined in order to
6287 build a `fred.syms' file that contains complete symbol information.
6288 A simple GDB invocation to do nothing but build a `.syms' file for future
6291 gdb -batch -nx -mapped -readnow programname
6293 The `.syms' file is specific to the host machine on which GDB is run.
6294 It holds an exact image of GDB's internal symbol table. It cannot be
6295 shared across multiple host platforms.
6297 * longjmp() handling
6299 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6300 siglongjmp() without losing control. This feature has not yet been ported to
6301 all systems. It currently works on many 386 platforms, all MIPS-based
6302 platforms (SGI, DECstation, etc), and Sun3/4.
6306 Preliminary work has been put in to support the new Solaris OS from Sun. At
6307 this time, it can control and debug processes, but it is not capable of
6312 As always, many many bug fixes. The major areas were with g++, and mipsread.
6313 People using the MIPS-based platforms should experience fewer mysterious
6314 crashes and trashed symbol tables.
6316 *** Changes in GDB-4.4:
6318 * New machines supported (host and target)
6320 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6322 BSD Reno on Vax vax-dec-bsd
6323 Ultrix on Vax vax-dec-ultrix
6325 * New machines supported (target)
6327 AMD 29000 embedded, using EBMON a29k-none-none
6331 GDB continues to improve its handling of C++. `References' work better.
6332 The demangler has also been improved, and now deals with symbols mangled as
6333 per the Annotated C++ Reference Guide.
6335 GDB also now handles `stabs' symbol information embedded in MIPS
6336 `ecoff' symbol tables. Since the ecoff format was not easily
6337 extensible to handle new languages such as C++, this appeared to be a
6338 good way to put C++ debugging info into MIPS binaries. This option
6339 will be supported in the GNU C compiler, version 2, when it is
6342 * New features for SVR4
6344 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6345 shared libraries. Debugging dynamically linked programs should present
6346 only minor differences from debugging statically linked programs.
6348 The `info proc' command will print out information about any process
6349 on an SVR4 system (including the one you are debugging). At the moment,
6350 it prints the address mappings of the process.
6352 If you bring up GDB on another SVR4 system, please send mail to
6353 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6355 * Better dynamic linking support in SunOS
6357 Reading symbols from shared libraries which contain debugging symbols
6358 now works properly. However, there remain issues such as automatic
6359 skipping of `transfer vector' code during function calls, which
6360 make it harder to debug code in a shared library, than to debug the
6361 same code linked statically.
6365 GDB is now using the latest `getopt' routines from the FSF. This
6366 version accepts the -- prefix for options with long names. GDB will
6367 continue to accept the old forms (-option and +option) as well.
6368 Various single letter abbreviations for options have been explicity
6369 added to the option table so that they won't get overshadowed in the
6370 future by other options that begin with the same letter.
6374 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6375 Many assorted bugs have been handled. Many more remain to be handled.
6376 See the various ChangeLog files (primarily in gdb and bfd) for details.
6379 *** Changes in GDB-4.3:
6381 * New machines supported (host and target)
6383 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6384 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6385 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6387 * Almost SCO Unix support
6389 We had hoped to support:
6390 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6391 (except for core file support), but we discovered very late in the release
6392 that it has problems with process groups that render gdb unusable. Sorry
6393 about that. I encourage people to fix it and post the fixes.
6395 * Preliminary ELF and DWARF support
6397 GDB can read ELF object files on System V Release 4, and can handle
6398 debugging records for C, in DWARF format, in ELF files. This support
6399 is preliminary. If you bring up GDB on another SVR4 system, please
6400 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6405 GDB now uses the latest `readline' library. One user-visible change
6406 is that two tabs will list possible command completions, which previously
6407 required typing M-? (meta-question mark, or ESC ?).
6411 The `stepi' bug that many of you noticed has been squashed.
6412 Many bugs in C++ have been handled. Many more remain to be handled.
6413 See the various ChangeLog files (primarily in gdb and bfd) for details.
6415 * State of the MIPS world (in case you wondered):
6417 GDB can understand the symbol tables emitted by the compilers
6418 supplied by most vendors of MIPS-based machines, including DEC. These
6419 symbol tables are in a format that essentially nobody else uses.
6421 Some versions of gcc come with an assembler post-processor called
6422 mips-tfile. This program is required if you want to do source-level
6423 debugging of gcc-compiled programs. I believe FSF does not ship
6424 mips-tfile with gcc version 1, but it will eventually come with gcc
6427 Debugging of g++ output remains a problem. g++ version 1.xx does not
6428 really support it at all. (If you're lucky, you should be able to get
6429 line numbers and stack traces to work, but no parameters or local
6430 variables.) With some work it should be possible to improve the
6433 When gcc version 2 is released, you will have somewhat better luck.
6434 However, even then you will get confusing results for inheritance and
6437 We will eventually provide full debugging of g++ output on
6438 DECstations. This will probably involve some kind of stabs-in-ecoff
6439 encapulation, but the details have not been worked out yet.
6442 *** Changes in GDB-4.2:
6444 * Improved configuration
6446 Only one copy of `configure' exists now, and it is not self-modifying.
6447 Porting BFD is simpler.
6451 The `step' and `next' commands now only stop at the first instruction
6452 of a source line. This prevents the multiple stops that used to occur
6453 in switch statements, for-loops, etc. `Step' continues to stop if a
6454 function that has debugging information is called within the line.
6458 Lots of small bugs fixed. More remain.
6460 * New host supported (not target)
6462 Intel 386 PC clone running Mach i386-none-mach
6465 *** Changes in GDB-4.1:
6467 * Multiple source language support
6469 GDB now has internal scaffolding to handle several source languages.
6470 It determines the type of each source file from its filename extension,
6471 and will switch expression parsing and number formatting to match the
6472 language of the function in the currently selected stack frame.
6473 You can also specifically set the language to be used, with
6474 `set language c' or `set language modula-2'.
6478 GDB now has preliminary support for the GNU Modula-2 compiler,
6479 currently under development at the State University of New York at
6480 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6481 continue through the fall of 1991 and into 1992.
6483 Other Modula-2 compilers are currently not supported, and attempting to
6484 debug programs compiled with them will likely result in an error as the
6485 symbol table is read. Feel free to work on it, though!
6487 There are hooks in GDB for strict type checking and range checking,
6488 in the `Modula-2 philosophy', but they do not currently work.
6492 GDB can now write to executable and core files (e.g. patch
6493 a variable's value). You must turn this switch on, specify
6494 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6495 by assigning a new value to a variable. Modifications take
6498 * Automatic SunOS shared library reading
6500 When you run your program, GDB automatically determines where its
6501 shared libraries (if any) have been loaded, and reads their symbols.
6502 The `share' command is no longer needed. This also works when
6503 examining core files.
6507 You can specify the number of lines that the `list' command shows.
6510 * New machines supported (host and target)
6512 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6513 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6514 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6516 * New hosts supported (not targets)
6518 IBM RT/PC: romp-ibm-aix or rtpc
6520 * New targets supported (not hosts)
6522 AMD 29000 embedded with COFF a29k-none-coff
6523 AMD 29000 embedded with a.out a29k-none-aout
6524 Ultracomputer remote kernel debug a29k-nyu-kern
6526 * New remote interfaces
6532 *** Changes in GDB-4.0:
6536 Wide output is wrapped at good places to make the output more readable.
6538 Gdb now supports cross-debugging from a host machine of one type to a
6539 target machine of another type. Communication with the target system
6540 is over serial lines. The ``target'' command handles connecting to the
6541 remote system; the ``load'' command will download a program into the
6542 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6543 also supports debugging of realtime processes running under VxWorks,
6544 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6545 stub on the target system.
6547 New CPUs supported include the AMD 29000 and Intel 960.
6549 GDB now reads object files and symbol tables via a ``binary file''
6550 library, which allows a single copy of GDB to debug programs of multiple
6551 object file types such as a.out and coff.
6553 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6554 refcard.dvi and refcard.ps are available to format it).
6557 * Control-Variable user interface simplified
6559 All variables that control the operation of the debugger can be set
6560 by the ``set'' command, and displayed by the ``show'' command.
6562 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6563 ``Show prompt'' produces the response:
6564 Gdb's prompt is new-gdb=>.
6566 What follows are the NEW set commands. The command ``help set'' will
6567 print a complete list of old and new set commands. ``help set FOO''
6568 will give a longer description of the variable FOO. ``show'' will show
6569 all of the variable descriptions and their current settings.
6571 confirm on/off: Enables warning questions for operations that are
6572 hard to recover from, e.g. rerunning the program while
6573 it is already running. Default is ON.
6575 editing on/off: Enables EMACS style command line editing
6576 of input. Previous lines can be recalled with
6577 control-P, the current line can be edited with control-B,
6578 you can search for commands with control-R, etc.
6581 history filename NAME: NAME is where the gdb command history
6582 will be stored. The default is .gdb_history,
6583 or the value of the environment variable
6586 history size N: The size, in commands, of the command history. The
6587 default is 256, or the value of the environment variable
6590 history save on/off: If this value is set to ON, the history file will
6591 be saved after exiting gdb. If set to OFF, the
6592 file will not be saved. The default is OFF.
6594 history expansion on/off: If this value is set to ON, then csh-like
6595 history expansion will be performed on
6596 command line input. The default is OFF.
6598 radix N: Sets the default radix for input and output. It can be set
6599 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6600 in the current radix, so "set radix 10" is always a no-op.
6602 height N: This integer value is the number of lines on a page. Default
6603 is 24, the current `stty rows'' setting, or the ``li#''
6604 setting from the termcap entry matching the environment
6607 width N: This integer value is the number of characters on a line.
6608 Default is 80, the current `stty cols'' setting, or the ``co#''
6609 setting from the termcap entry matching the environment
6612 Note: ``set screensize'' is obsolete. Use ``set height'' and
6613 ``set width'' instead.
6615 print address on/off: Print memory addresses in various command displays,
6616 such as stack traces and structure values. Gdb looks
6617 more ``symbolic'' if you turn this off; it looks more
6618 ``machine level'' with it on. Default is ON.
6620 print array on/off: Prettyprint arrays. New convenient format! Default
6623 print demangle on/off: Print C++ symbols in "source" form if on,
6626 print asm-demangle on/off: Same, for assembler level printouts
6629 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6632 * Support for Epoch Environment.
6634 The epoch environment is a version of Emacs v18 with windowing. One
6635 new command, ``inspect'', is identical to ``print'', except that if you
6636 are running in the epoch environment, the value is printed in its own
6640 * Support for Shared Libraries
6642 GDB can now debug programs and core files that use SunOS shared libraries.
6643 Symbols from a shared library cannot be referenced
6644 before the shared library has been linked with the program (this
6645 happens after you type ``run'' and before the function main() is entered).
6646 At any time after this linking (including when examining core files
6647 from dynamically linked programs), gdb reads the symbols from each
6648 shared library when you type the ``sharedlibrary'' command.
6649 It can be abbreviated ``share''.
6651 sharedlibrary REGEXP: Load shared object library symbols for files
6652 matching a unix regular expression. No argument
6653 indicates to load symbols for all shared libraries.
6655 info sharedlibrary: Status of loaded shared libraries.
6660 A watchpoint stops execution of a program whenever the value of an
6661 expression changes. Checking for this slows down execution
6662 tremendously whenever you are in the scope of the expression, but is
6663 quite useful for catching tough ``bit-spreader'' or pointer misuse
6664 problems. Some machines such as the 386 have hardware for doing this
6665 more quickly, and future versions of gdb will use this hardware.
6667 watch EXP: Set a watchpoint (breakpoint) for an expression.
6669 info watchpoints: Information about your watchpoints.
6671 delete N: Deletes watchpoint number N (same as breakpoints).
6672 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6673 enable N: Re-enables watchpoint number N (same as breakpoints).
6676 * C++ multiple inheritance
6678 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6681 * C++ exception handling
6683 Gdb now supports limited C++ exception handling. Besides the existing
6684 ability to breakpoint on an exception handler, gdb can breakpoint on
6685 the raising of an exception (before the stack is peeled back to the
6688 catch FOO: If there is a FOO exception handler in the dynamic scope,
6689 set a breakpoint to catch exceptions which may be raised there.
6690 Multiple exceptions (``catch foo bar baz'') may be caught.
6692 info catch: Lists all exceptions which may be caught in the
6693 current stack frame.
6696 * Minor command changes
6698 The command ``call func (arg, arg, ...)'' now acts like the print
6699 command, except it does not print or save a value if the function's result
6700 is void. This is similar to dbx usage.
6702 The ``up'' and ``down'' commands now always print the frame they end up
6703 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6704 frames without printing.
6706 * New directory command
6708 'dir' now adds directories to the FRONT of the source search path.
6709 The path starts off empty. Source files that contain debug information
6710 about the directory in which they were compiled can be found even
6711 with an empty path; Sun CC and GCC include this information. If GDB can't
6712 find your source file in the current directory, type "dir .".
6714 * Configuring GDB for compilation
6716 For normal use, type ``./configure host''. See README or gdb.texinfo
6719 GDB now handles cross debugging. If you are remotely debugging between
6720 two different machines, type ``./configure host -target=targ''.
6721 Host is the machine where GDB will run; targ is the machine
6722 where the program that you are debugging will run.
projects / external / binutils.git / blob