1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.12
6 * Building GDB and GDBserver now requires a C++11 compiler.
8 For example, GCC 4.8 or later.
10 It is no longer possible to build GDB or GDBserver with a C
11 compiler. The --disable-build-with-cxx configure option has been
14 * Building GDB and GDBserver now requires GNU make >= 3.81.
16 It is no longer supported to build GDB or GDBserver with another
17 implementation of the make program or an earlier version of GNU make.
19 * Native debugging on MS-Windows supports command-line redirection
21 Command-line arguments used for starting programs on MS-Windows can
22 now include redirection symbols supported by native Windows shells,
23 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
24 as "run", "start", and "set args", as well as the corresponding MI
27 * Support for thread names on MS-Windows.
29 GDB now catches and handles the special exception that programs
30 running on MS-Windows use to assign names to threads in the
33 * Support for Java programs compiled with gcj has been removed.
35 * User commands now accept an unlimited number of arguments.
36 Previously, only up to 10 was accepted.
38 * The "eval" command now expands user-defined command arguments.
40 This makes it easier to process a variable number of arguments:
45 eval "print $arg%d", $i
50 * New native configurations
52 FreeBSD/mips mips*-*-freebsd
57 Synopsys ARC arc*-*-elf32
58 FreeBSD/mips mips*-*-freebsd
60 *** Changes in GDB 7.12
62 * GDB and GDBserver now build with a C++ compiler by default.
64 The --enable-build-with-cxx configure option is now enabled by
65 default. One must now explicitly configure with
66 --disable-build-with-cxx in order to build with a C compiler. This
67 option will be removed in a future release.
69 * GDBserver now supports recording btrace without maintaining an active
72 * GDB now supports a negative repeat count in the 'x' command to examine
73 memory backward from the given address. For example:
76 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
77 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
78 (gdb) x/-5i 0x0000000000400580
79 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
80 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
81 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
82 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
83 0x40057b <main(int, char**)+25>:
84 callq 0x400536 <Func1(int, char const*)>
86 * Fortran: Support structures with fields of dynamic types and
87 arrays of dynamic types.
89 * The symbol dumping maintenance commands have new syntax.
90 maint print symbols [-pc address] [--] [filename]
91 maint print symbols [-objfile objfile] [-source source] [--] [filename]
92 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
93 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
94 maint print msymbols [-objfile objfile] [--] [filename]
96 * GDB now supports multibit bitfields and enums in target register
99 * New Python-based convenience function $_as_string(val), which returns
100 the textual representation of a value. This function is especially
101 useful to obtain the text label of an enum value.
103 * Intel MPX bound violation handling.
105 Segmentation faults caused by a Intel MPX boundary violation
106 now display the kind of violation (upper or lower), the memory
107 address accessed and the memory bounds, along with the usual
108 signal received and code location.
112 Program received signal SIGSEGV, Segmentation fault
113 Upper bound violation while accessing address 0x7fffffffc3b3
114 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
115 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
117 * Rust language support.
118 GDB now supports debugging programs written in the Rust programming
119 language. See https://www.rust-lang.org/ for more information about
122 * Support for running interpreters on specified input/output devices
124 GDB now supports a new mechanism that allows frontends to provide
125 fully featured GDB console views, as a better alternative to
126 building such views on top of the "-interpreter-exec console"
127 command. See the new "new-ui" command below. With that command,
128 frontends can now start GDB in the traditional command-line mode
129 running in an embedded terminal emulator widget, and create a
130 separate MI interpreter running on a specified i/o device. In this
131 way, GDB handles line editing, history, tab completion, etc. in the
132 console all by itself, and the GUI uses the separate MI interpreter
133 for its own control and synchronization, invisible to the command
136 * The "catch syscall" command catches groups of related syscalls.
138 The "catch syscall" command now supports catching a group of related
139 syscalls using the 'group:' or 'g:' prefix.
144 skip -gfile file-glob-pattern
145 skip -function function
146 skip -rfunction regular-expression
147 A generalized form of the skip command, with new support for
148 glob-style file names and regular expressions for function names.
149 Additionally, a file spec and a function spec may now be combined.
151 maint info line-table REGEXP
152 Display the contents of GDB's internal line table data struture.
155 Run any GDB unit tests that were compiled in.
158 Start a new user interface instance running INTERP as interpreter,
159 using the TTY file for input/output.
163 ** gdb.Breakpoint objects have a new attribute "pending", which
164 indicates whether the breakpoint is pending.
165 ** Three new breakpoint-related events have been added:
166 gdb.breakpoint_created, gdb.breakpoint_modified, and
167 gdb.breakpoint_deleted.
170 Signal ("set") the given MS-Windows event object. This is used in
171 conjunction with the Windows JIT debugging (AeDebug) support, where
172 the OS suspends a crashing process until a debugger can attach to
173 it. Resuming the crashing process, in order to debug it, is done by
176 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
177 was added in GDBserver, including JIT compiling fast tracepoint's
178 conditional expression bytecode into native code.
180 * Support for various remote target protocols and ROM monitors has
183 target m32rsdi Remote M32R debugging over SDI
184 target mips MIPS remote debugging protocol
185 target pmon PMON ROM monitor
186 target ddb NEC's DDB variant of PMON for Vr4300
187 target rockhopper NEC RockHopper variant of PMON
188 target lsi LSI variant of PMO
190 * Support for tracepoints and fast tracepoints on powerpc-linux,
191 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
192 including JIT compiling fast tracepoint's conditional expression
193 bytecode into native code.
195 * MI async record =record-started now includes the method and format used for
196 recording. For example:
198 =record-started,thread-group="i1",method="btrace",format="bts"
200 * MI async record =thread-selected now includes the frame field. For example:
202 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
206 Andes NDS32 nds32*-*-elf
208 *** Changes in GDB 7.11
210 * GDB now supports debugging kernel-based threads on FreeBSD.
212 * Per-inferior thread numbers
214 Thread numbers are now per inferior instead of global. If you're
215 debugging multiple inferiors, GDB displays thread IDs using a
216 qualified INF_NUM.THR_NUM form. For example:
220 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
221 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
222 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
223 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
225 As consequence, thread numbers as visible in the $_thread
226 convenience variable and in Python's InferiorThread.num attribute
227 are no longer unique between inferiors.
229 GDB now maintains a second thread ID per thread, referred to as the
230 global thread ID, which is the new equivalent of thread numbers in
231 previous releases. See also $_gthread below.
233 For backwards compatibility, MI's thread IDs always refer to global
236 * Commands that accept thread IDs now accept the qualified
237 INF_NUM.THR_NUM form as well. For example:
240 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
243 * In commands that accept a list of thread IDs, you can now refer to
244 all threads of an inferior using a star wildcard. GDB accepts
245 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
246 refer to all threads of the current inferior. For example, "info
249 * You can use "info threads -gid" to display the global thread ID of
252 * The new convenience variable $_gthread holds the global number of
255 * The new convenience variable $_inferior holds the number of the
258 * GDB now displays the ID and name of the thread that hit a breakpoint
259 or received a signal, if your program is multi-threaded. For
262 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
263 Thread 1 "main" received signal SIGINT, Interrupt.
265 * Record btrace now supports non-stop mode.
267 * Support for tracepoints on aarch64-linux was added in GDBserver.
269 * The 'record instruction-history' command now indicates speculative execution
270 when using the Intel Processor Trace recording format.
272 * GDB now allows users to specify explicit locations, bypassing
273 the linespec parser. This feature is also available to GDB/MI
276 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
277 GDB now is able to debug both AArch64 applications and ARM applications
280 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
281 including JIT compiling fast tracepoint's conditional expression bytecode
284 * GDB now supports displaced stepping on AArch64 GNU/Linux.
286 * "info threads", "info inferiors", "info display", "info checkpoints"
287 and "maint info program-spaces" now list the corresponding items in
288 ascending ID order, for consistency with all other "info" commands.
290 * In Ada, the overloads selection menu has been enhanced to display the
291 parameter types and the return types for the matching overloaded subprograms.
295 maint set target-non-stop (on|off|auto)
296 maint show target-non-stop
297 Control whether GDB targets always operate in non-stop mode even if
298 "set non-stop" is "off". The default is "auto", meaning non-stop
299 mode is enabled if supported by the target.
301 maint set bfd-sharing
302 maint show bfd-sharing
303 Control the reuse of bfd objects.
307 Control display of debugging info regarding bfd caching.
311 Control display of debugging info regarding FreeBSD threads.
313 set remote multiprocess-extensions-packet
314 show remote multiprocess-extensions-packet
315 Set/show the use of the remote protocol multiprocess extensions.
317 set remote thread-events
318 show remote thread-events
319 Set/show the use of thread create/exit events.
321 set ada print-signatures on|off
322 show ada print-signatures"
323 Control whether parameter types and return types are displayed in overloads
324 selection menus. It is activaled (@code{on}) by default.
328 Controls the maximum size of memory, in bytes, that GDB will
329 allocate for value contents. Prevents incorrect programs from
330 causing GDB to allocate overly large buffers. Default is 64k.
332 * The "disassemble" command accepts a new modifier: /s.
333 It prints mixed source+disassembly like /m with two differences:
334 - disassembled instructions are now printed in program order, and
335 - and source for all relevant files is now printed.
336 The "/m" option is now considered deprecated: its "source-centric"
337 output hasn't proved useful in practice.
339 * The "record instruction-history" command accepts a new modifier: /s.
340 It behaves exactly like /m and prints mixed source+disassembly.
342 * The "set scheduler-locking" command supports a new mode "replay".
343 It behaves like "off" in record mode and like "on" in replay mode.
345 * Support for various ROM monitors has been removed:
347 target dbug dBUG ROM monitor for Motorola ColdFire
348 target picobug Motorola picobug monitor
349 target dink32 DINK32 ROM monitor for PowerPC
350 target m32r Renesas M32R/D ROM monitor
351 target mon2000 mon2000 ROM monitor
352 target ppcbug PPCBUG ROM monitor for PowerPC
354 * Support for reading/writing memory and extracting values on architectures
355 whose memory is addressable in units of any integral multiple of 8 bits.
360 Indicates that an exec system call was executed.
362 exec-events feature in qSupported
363 The qSupported packet allows GDB to request support for exec
364 events using the new 'gdbfeature' exec-event, and the qSupported
365 response can contain the corresponding 'stubfeature'. Set and
366 show commands can be used to display whether these features are enabled.
369 Equivalent to interrupting with the ^C character, but works in
372 thread created stop reason (T05 create:...)
373 Indicates that the thread was just created and is stopped at entry.
375 thread exit stop reply (w exitcode;tid)
376 Indicates that the thread has terminated.
379 Enables/disables thread create and exit event reporting. For
380 example, this is used in non-stop mode when GDB stops a set of
381 threads and synchronously waits for the their corresponding stop
382 replies. Without exit events, if one of the threads exits, GDB
383 would hang forever not knowing that it should no longer expect a
384 stop for that same thread.
387 Indicates that there are no resumed threads left in the target (all
388 threads are stopped). The remote stub reports support for this stop
389 reply to GDB's qSupported query.
392 Enables/disables catching syscalls from the inferior process.
393 The remote stub reports support for this packet to GDB's qSupported query.
395 syscall_entry stop reason
396 Indicates that a syscall was just called.
398 syscall_return stop reason
399 Indicates that a syscall just returned.
401 * Extended-remote exec events
403 ** GDB now has support for exec events on extended-remote Linux targets.
404 For such targets with Linux kernels 2.5.46 and later, this enables
405 follow-exec-mode and exec catchpoints.
407 set remote exec-event-feature-packet
408 show remote exec-event-feature-packet
409 Set/show the use of the remote exec event feature.
411 * Thread names in remote protocol
413 The reply to qXfer:threads:read may now include a name attribute for each
416 * Target remote mode fork and exec events
418 ** GDB now has support for fork and exec events on target remote mode
419 Linux targets. For such targets with Linux kernels 2.5.46 and later,
420 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
421 fork and exec catchpoints.
423 * Remote syscall events
425 ** GDB now has support for catch syscall on remote Linux targets,
426 currently enabled on x86/x86_64 architectures.
428 set remote catch-syscall-packet
429 show remote catch-syscall-packet
430 Set/show the use of the remote catch syscall feature.
434 ** The -var-set-format command now accepts the zero-hexadecimal
435 format. It outputs data in hexadecimal format with zero-padding on the
440 ** gdb.InferiorThread objects have a new attribute "global_num",
441 which refers to the thread's global thread ID. The existing
442 "num" attribute now refers to the thread's per-inferior number.
443 See "Per-inferior thread numbers" above.
444 ** gdb.InferiorThread objects have a new attribute "inferior", which
445 is the Inferior object the thread belongs to.
447 *** Changes in GDB 7.10
449 * Support for process record-replay and reverse debugging on aarch64*-linux*
450 targets has been added. GDB now supports recording of A64 instruction set
451 including advance SIMD instructions.
453 * Support for Sun's version of the "stabs" debug file format has been removed.
455 * GDB now honors the content of the file /proc/PID/coredump_filter
456 (PID is the process ID) on GNU/Linux systems. This file can be used
457 to specify the types of memory mappings that will be included in a
458 corefile. For more information, please refer to the manual page of
459 "core(5)". GDB also has a new command: "set use-coredump-filter
460 on|off". It allows to set whether GDB will read the content of the
461 /proc/PID/coredump_filter file when generating a corefile.
463 * The "info os" command on GNU/Linux can now display information on
465 "info os cpus" Listing of all cpus/cores on the system
467 * GDB has two new commands: "set serial parity odd|even|none" and
468 "show serial parity". These allows to set or show parity for the
471 * The "info source" command now displays the producer string if it was
472 present in the debug info. This typically includes the compiler version
473 and may include things like its command line arguments.
475 * The "info dll", an alias of the "info sharedlibrary" command,
476 is now available on all platforms.
478 * Directory names supplied to the "set sysroot" commands may be
479 prefixed with "target:" to tell GDB to access shared libraries from
480 the target system, be it local or remote. This replaces the prefix
481 "remote:". The default sysroot has been changed from "" to
482 "target:". "remote:" is automatically converted to "target:" for
483 backward compatibility.
485 * The system root specified by "set sysroot" will be prepended to the
486 filename of the main executable (if reported to GDB as absolute by
487 the operating system) when starting processes remotely, and when
488 attaching to already-running local or remote processes.
490 * GDB now supports automatic location and retrieval of executable
491 files from remote targets. Remote debugging can now be initiated
492 using only a "target remote" or "target extended-remote" command
493 (no "set sysroot" or "file" commands are required). See "New remote
496 * The "dump" command now supports verilog hex format.
498 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
500 * On GNU/Linux, GDB and gdbserver are now able to access executable
501 and shared library files without a "set sysroot" command when
502 attaching to processes running in different mount namespaces from
503 the debugger. This makes it possible to attach to processes in
504 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
505 See "New remote packets" below.
507 * The "tui reg" command now provides completion for all of the
508 available register groups, including target specific groups.
510 * The HISTSIZE environment variable is no longer read when determining
511 the size of GDB's command history. GDB now instead reads the dedicated
512 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
513 disables truncation of command history. Non-numeric values of GDBHISTSIZE
518 ** Memory ports can now be unbuffered.
522 ** gdb.Objfile objects have a new attribute "username",
523 which is the name of the objfile as specified by the user,
524 without, for example, resolving symlinks.
525 ** You can now write frame unwinders in Python.
526 ** gdb.Type objects have a new method "optimized_out",
527 returning optimized out gdb.Value instance of this type.
528 ** gdb.Value objects have new methods "reference_value" and
529 "const_value" which return a reference to the value and a
530 "const" version of the value respectively.
534 maint print symbol-cache
535 Print the contents of the symbol cache.
537 maint print symbol-cache-statistics
538 Print statistics of symbol cache usage.
540 maint flush-symbol-cache
541 Flush the contents of the symbol cache.
545 Start branch trace recording using Branch Trace Store (BTS) format.
548 Evaluate expression by using the compiler and print result.
552 Explicit commands for enabling and disabling tui mode.
555 set mpx bound on i386 and amd64
556 Support for bound table investigation on Intel MPX enabled applications.
560 Start branch trace recording using Intel Processor Trace format.
563 Print information about branch tracing internals.
565 maint btrace packet-history
566 Print the raw branch tracing data.
568 maint btrace clear-packet-history
569 Discard the stored raw branch tracing data.
572 Discard all branch tracing data. It will be fetched and processed
573 anew by the next "record" command.
578 Renamed from "set debug dwarf2-die".
580 Renamed from "show debug dwarf2-die".
583 Renamed from "set debug dwarf2-read".
584 show debug dwarf-read
585 Renamed from "show debug dwarf2-read".
587 maint set dwarf always-disassemble
588 Renamed from "maint set dwarf2 always-disassemble".
589 maint show dwarf always-disassemble
590 Renamed from "maint show dwarf2 always-disassemble".
592 maint set dwarf max-cache-age
593 Renamed from "maint set dwarf2 max-cache-age".
594 maint show dwarf max-cache-age
595 Renamed from "maint show dwarf2 max-cache-age".
598 show debug dwarf-line
599 Control display of debugging info regarding DWARF line processing.
603 Set the maximum number of candidates to be considered during
604 completion. The default value is 200. This limit allows GDB
605 to avoid generating large completion lists, the computation of
606 which can cause the debugger to become temporarily unresponsive.
608 set history remove-duplicates
609 show history remove-duplicates
610 Control the removal of duplicate history entries.
612 maint set symbol-cache-size
613 maint show symbol-cache-size
614 Control the size of the symbol cache.
616 set|show record btrace bts buffer-size
617 Set and show the size of the ring buffer used for branch tracing in
619 The obtained size may differ from the requested size. Use "info
620 record" to see the obtained buffer size.
622 set debug linux-namespaces
623 show debug linux-namespaces
624 Control display of debugging info regarding Linux namespaces.
626 set|show record btrace pt buffer-size
627 Set and show the size of the ring buffer used for branch tracing in
628 Intel Processor Trace format.
629 The obtained size may differ from the requested size. Use "info
630 record" to see the obtained buffer size.
632 maint set|show btrace pt skip-pad
633 Set and show whether PAD packets are skipped when computing the
636 * The command 'thread apply all' can now support new option '-ascending'
637 to call its specified command for all threads in ascending order.
639 * Python/Guile scripting
641 ** GDB now supports auto-loading of Python/Guile scripts contained in the
642 special section named `.debug_gdb_scripts'.
646 qXfer:btrace-conf:read
647 Return the branch trace configuration for the current thread.
649 Qbtrace-conf:bts:size
650 Set the requested ring buffer size for branch tracing in BTS format.
653 Enable Intel Procesor Trace-based branch tracing for the current
654 process. The remote stub reports support for this packet to GDB's
658 Set the requested ring buffer size for branch tracing in Intel Processor
662 Indicates a memory breakpoint instruction was executed, irrespective
663 of whether it was GDB that planted the breakpoint or the breakpoint
664 is hardcoded in the program. This is required for correct non-stop
668 Indicates the target stopped for a hardware breakpoint. This is
669 required for correct non-stop mode operation.
672 Return information about files on the remote system.
675 Return the full absolute name of the file that was executed to
676 create a process running on the remote system.
679 Select the filesystem on which vFile: operations with filename
680 arguments will operate. This is required for GDB to be able to
681 access files on remote targets where the remote stub does not
682 share a common filesystem with the inferior(s).
685 Indicates that a fork system call was executed.
688 Indicates that a vfork system call was executed.
690 vforkdone stop reason
691 Indicates that a vfork child of the specified process has executed
692 an exec or exit, allowing the vfork parent to resume execution.
694 fork-events and vfork-events features in qSupported
695 The qSupported packet allows GDB to request support for fork and
696 vfork events using new 'gdbfeatures' fork-events and vfork-events,
697 and the qSupported response can contain the corresponding
698 'stubfeatures'. Set and show commands can be used to display
699 whether these features are enabled.
701 * Extended-remote fork events
703 ** GDB now has support for fork events on extended-remote Linux
704 targets. For targets with Linux kernels 2.5.60 and later, this
705 enables follow-fork-mode and detach-on-fork for both fork and
706 vfork, as well as fork and vfork catchpoints.
708 * The info record command now shows the recording format and the
709 branch tracing configuration for the current thread when using
710 the btrace record target.
711 For the BTS format, it shows the ring buffer size.
713 * GDB now has support for DTrace USDT (Userland Static Defined
714 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
716 * GDB now supports access to vector registers on S/390 GNU/Linux
719 * Removed command line options
721 -xdb HP-UX XDB compatibility mode.
723 * Removed targets and native configurations
725 HP/PA running HP-UX hppa*-*-hpux*
726 Itanium running HP-UX ia64-*-hpux*
728 * New configure options
731 This configure option allows the user to build GDB with support for
732 Intel Processor Trace (default: auto). This requires libipt.
734 --with-libipt-prefix=PATH
735 Specify the path to the version of libipt that GDB should use.
736 $PATH/include should contain the intel-pt.h header and
737 $PATH/lib should contain the libipt.so library.
739 *** Changes in GDB 7.9.1
743 ** Xmethods can now specify a result type.
745 *** Changes in GDB 7.9
747 * GDB now supports hardware watchpoints on x86 GNU Hurd.
751 ** You can now access frame registers from Python scripts.
752 ** New attribute 'producer' for gdb.Symtab objects.
753 ** gdb.Objfile objects have a new attribute "progspace",
754 which is the gdb.Progspace object of the containing program space.
755 ** gdb.Objfile objects have a new attribute "owner".
756 ** gdb.Objfile objects have a new attribute "build_id",
757 which is the build ID generated when the file was built.
758 ** gdb.Objfile objects have a new method "add_separate_debug_file".
759 ** A new event "gdb.clear_objfiles" has been added, triggered when
760 selecting a new file to debug.
761 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
762 ** New function gdb.lookup_objfile.
764 New events which are triggered when GDB modifies the state of the
767 ** gdb.events.inferior_call_pre: Function call is about to be made.
768 ** gdb.events.inferior_call_post: Function call has just been made.
769 ** gdb.events.memory_changed: A memory location has been altered.
770 ** gdb.events.register_changed: A register has been altered.
772 * New Python-based convenience functions:
774 ** $_caller_is(name [, number_of_frames])
775 ** $_caller_matches(regexp [, number_of_frames])
776 ** $_any_caller_is(name [, number_of_frames])
777 ** $_any_caller_matches(regexp [, number_of_frames])
779 * GDB now supports the compilation and injection of source code into
780 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
781 to compile the source code to object code, and if successful, inject
782 and execute that code within the current context of the inferior.
783 Currently the C language is supported. The commands used to
784 interface with this new feature are:
786 compile code [-raw|-r] [--] [source code]
787 compile file [-raw|-r] filename
791 demangle [-l language] [--] name
792 Demangle "name" in the specified language, or the current language
793 if elided. This command is renamed from the "maint demangle" command.
794 The latter is kept as a no-op to avoid "maint demangle" being interpreted
795 as "maint demangler-warning".
797 queue-signal signal-name-or-number
798 Queue a signal to be delivered to the thread when it is resumed.
800 add-auto-load-scripts-directory directory
801 Add entries to the list of directories from which to load auto-loaded
804 maint print user-registers
805 List all currently available "user" registers.
807 compile code [-r|-raw] [--] [source code]
808 Compile, inject, and execute in the inferior the executable object
809 code produced by compiling the provided source code.
811 compile file [-r|-raw] filename
812 Compile and inject into the inferior the executable object code
813 produced by compiling the source code stored in the filename
816 * On resume, GDB now always passes the signal the program had stopped
817 for to the thread the signal was sent to, even if the user changed
818 threads before resuming. Previously GDB would often (but not
819 always) deliver the signal to the thread that happens to be current
822 * Conversely, the "signal" command now consistently delivers the
823 requested signal to the current thread. GDB now asks for
824 confirmation if the program had stopped for a signal and the user
825 switched threads meanwhile.
827 * "breakpoint always-inserted" modes "off" and "auto" merged.
829 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
830 won't remove breakpoints from the target until all threads stop,
831 even in non-stop mode. The "auto" mode has been removed, and "off"
832 is now the default mode.
836 set debug symbol-lookup
837 show debug symbol-lookup
838 Control display of debugging info regarding symbol lookup.
842 ** The -list-thread-groups command outputs an exit-code field for
843 inferiors that have exited.
847 MIPS SDE mips*-sde*-elf*
851 Support for these obsolete configurations has been removed.
853 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
854 SGI Irix-5.x mips-*-irix5*
855 SGI Irix-6.x mips-*-irix6*
856 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
857 VAX running Ultrix vax-*-ultrix*
859 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
860 and "assf"), have been removed. Use the "sharedlibrary" command, or
861 its alias "share", instead.
863 *** Changes in GDB 7.8
865 * New command line options
868 This is an alias for the --data-directory option.
870 * GDB supports printing and modifying of variable length automatic arrays
871 as specified in ISO C99.
873 * The ARM simulator now supports instruction level tracing
874 with or without disassembly.
878 GDB now has support for scripting using Guile. Whether this is
879 available is determined at configure time.
880 Guile version 2.0 or greater is required.
881 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
883 * New commands (for set/show, see "New options" below)
887 Invoke CODE by passing it to the Guile interpreter.
891 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
893 info auto-load guile-scripts [regexp]
894 Print the list of automatically loaded Guile scripts.
896 * The source command is now capable of sourcing Guile scripts.
897 This feature is dependent on the debugger being built with Guile support.
901 set print symbol-loading (off|brief|full)
902 show print symbol-loading
903 Control whether to print informational messages when loading symbol
904 information for a file. The default is "full", but when debugging
905 programs with large numbers of shared libraries the amount of output
908 set guile print-stack (none|message|full)
909 show guile print-stack
910 Show a stack trace when an error is encountered in a Guile script.
912 set auto-load guile-scripts (on|off)
913 show auto-load guile-scripts
914 Control auto-loading of Guile script files.
916 maint ada set ignore-descriptive-types (on|off)
917 maint ada show ignore-descriptive-types
918 Control whether the debugger should ignore descriptive types in Ada
919 programs. The default is not to ignore the descriptive types. See
920 the user manual for more details on descriptive types and the intended
921 usage of this option.
923 set auto-connect-native-target
925 Control whether GDB is allowed to automatically connect to the
926 native target for the run, attach, etc. commands when not connected
927 to any target yet. See also "target native" below.
929 set record btrace replay-memory-access (read-only|read-write)
930 show record btrace replay-memory-access
931 Control what memory accesses are allowed during replay.
933 maint set target-async (on|off)
934 maint show target-async
935 This controls whether GDB targets operate in synchronous or
936 asynchronous mode. Normally the default is asynchronous, if it is
937 available; but this can be changed to more easily debug problems
938 occurring only in synchronous mode.
940 set mi-async (on|off)
942 Control whether MI asynchronous mode is preferred. This supersedes
943 "set target-async" of previous GDB versions.
945 * "set target-async" is deprecated as a CLI option and is now an alias
946 for "set mi-async" (only puts MI into async mode).
948 * Background execution commands (e.g., "c&", "s&", etc.) are now
949 possible ``out of the box'' if the target supports them. Previously
950 the user would need to explicitly enable the possibility with the
951 "set target-async on" command.
953 * New features in the GDB remote stub, GDBserver
955 ** New option --debug-format=option1[,option2,...] allows one to add
956 additional text to each output. At present only timestamps
957 are supported: --debug-format=timestamps.
958 Timestamps can also be turned on with the
959 "monitor set debug-format timestamps" command from GDB.
961 * The 'record instruction-history' command now starts counting instructions
962 at one. This also affects the instruction ranges reported by the
963 'record function-call-history' command when given the /i modifier.
965 * The command 'record function-call-history' supports a new modifier '/c' to
966 indent the function names based on their call stack depth.
967 The fields for the '/i' and '/l' modifier have been reordered.
968 The source line range is now prefixed with 'at'.
969 The instruction range is now prefixed with 'inst'.
970 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
971 "record instruction-history" and "list" commands.
973 * The ranges given as arguments to the 'record function-call-history' and
974 'record instruction-history' commands are now inclusive.
976 * The btrace record target now supports the 'record goto' command.
977 For locations inside the execution trace, the back trace is computed
978 based on the information stored in the execution trace.
980 * The btrace record target supports limited reverse execution and replay.
981 The target does not record data and therefore does not allow reading
984 * The "catch syscall" command now works on s390*-linux* targets.
986 * The "compare-sections" command is no longer specific to target
987 remote. It now works with all targets.
989 * All native targets are now consistently called "native".
990 Consequently, the "target child", "target GNU", "target djgpp",
991 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
992 commands have been replaced with "target native". The QNX/NTO port
993 leaves the "procfs" target in place and adds a "native" target for
994 consistency with other ports. The impact on users should be minimal
995 as these commands previously either throwed an error, or were
996 no-ops. The target's name is visible in the output of the following
997 commands: "help target", "info target", "info files", "maint print
1000 * The "target native" command now connects to the native target. This
1001 can be used to launch native programs even when "set
1002 auto-connect-native-target" is set to off.
1004 * GDB now supports access to Intel MPX registers on GNU/Linux.
1006 * Support for Intel AVX-512 registers on GNU/Linux.
1007 Support displaying and modifying Intel AVX-512 registers
1008 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1010 * New remote packets
1012 qXfer:btrace:read's annex
1013 The qXfer:btrace:read packet supports a new annex 'delta' to read
1014 branch trace incrementally.
1018 ** Valid Python operations on gdb.Value objects representing
1019 structs/classes invoke the corresponding overloaded operators if
1021 ** New `Xmethods' feature in the Python API. Xmethods are
1022 additional methods or replacements for existing methods of a C++
1023 class. This feature is useful for those cases where a method
1024 defined in C++ source code could be inlined or optimized out by
1025 the compiler, making it unavailable to GDB.
1028 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1030 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1031 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1032 its alias "share", instead.
1034 * The commands "set remotebaud" and "show remotebaud" are no longer
1035 supported. Use "set serial baud" and "show serial baud" (respectively)
1040 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1041 target-async". The latter is left as a deprecated alias of the
1042 former for backward compatibility. If the target supports it,
1043 CLI background execution commands are now always possible by
1044 default, independently of whether the frontend stated a
1045 preference for asynchronous execution with "-gdb-set mi-async".
1046 Previously "-gdb-set target-async off" affected both MI execution
1047 commands and CLI execution commands.
1049 *** Changes in GDB 7.7
1051 * Improved support for process record-replay and reverse debugging on
1052 arm*-linux* targets. Support for thumb32 and syscall instruction
1053 recording has been added.
1055 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1057 * GDB now supports Fission DWP file format version 2.
1058 http://gcc.gnu.org/wiki/DebugFission
1060 * New convenience function "$_isvoid", to check whether an expression
1061 is void. A void expression is an expression where the type of the
1062 result is "void". For example, some convenience variables may be
1063 "void" when evaluated (e.g., "$_exitcode" before the execution of
1064 the program being debugged; or an undefined convenience variable).
1065 Another example, when calling a function whose return type is
1068 * The "maintenance print objfiles" command now takes an optional regexp.
1070 * The "catch syscall" command now works on arm*-linux* targets.
1072 * GDB now consistently shows "<not saved>" when printing values of
1073 registers the debug info indicates have not been saved in the frame
1074 and there's nowhere to retrieve them from
1075 (callee-saved/call-clobbered registers):
1080 (gdb) info registers rax
1083 Before, the former would print "<optimized out>", and the latter
1084 "*value not available*".
1086 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1091 ** Frame filters and frame decorators have been added.
1092 ** Temporary breakpoints are now supported.
1093 ** Line tables representation has been added.
1094 ** New attribute 'parent_type' for gdb.Field objects.
1095 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1096 ** New attribute 'name' for gdb.Type objects.
1100 Nios II ELF nios2*-*-elf
1101 Nios II GNU/Linux nios2*-*-linux
1102 Texas Instruments MSP430 msp430*-*-elf
1104 * Removed native configurations
1106 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1107 been removed. ELF variants of these configurations are kept supported.
1109 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1110 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1111 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1112 i[34567]86-*-openbsd3.[0-3]
1113 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1114 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1115 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1119 Like "catch throw", but catches a re-thrown exception.
1120 maint check-psymtabs
1121 Renamed from old "maint check-symtabs".
1123 Perform consistency checks on symtabs.
1124 maint expand-symtabs
1125 Expand symtabs matching an optional regexp.
1128 Display the details of GDB configure-time options.
1130 maint set|show per-command
1131 maint set|show per-command space
1132 maint set|show per-command time
1133 maint set|show per-command symtab
1134 Enable display of per-command gdb resource usage.
1136 remove-symbol-file FILENAME
1137 remove-symbol-file -a ADDRESS
1138 Remove a symbol file added via add-symbol-file. The file to remove
1139 can be identified by its filename or by an address that lies within
1140 the boundaries of this symbol file in memory.
1143 info exceptions REGEXP
1144 Display the list of Ada exceptions defined in the program being
1145 debugged. If provided, only the exceptions whose names match REGEXP
1150 set debug symfile off|on
1152 Control display of debugging info regarding reading symbol files and
1153 symbol tables within those files
1155 set print raw frame-arguments
1156 show print raw frame-arguments
1157 Set/show whether to print frame arguments in raw mode,
1158 disregarding any defined pretty-printers.
1160 set remote trace-status-packet
1161 show remote trace-status-packet
1162 Set/show the use of remote protocol qTStatus packet.
1166 Control display of debugging messages related to Nios II targets.
1170 Control whether target-assisted range stepping is enabled.
1172 set startup-with-shell
1173 show startup-with-shell
1174 Specifies whether Unix child processes are started via a shell or
1179 Use the target memory cache for accesses to the code segment. This
1180 improves performance of remote debugging (particularly disassembly).
1182 * You can now use a literal value 'unlimited' for options that
1183 interpret 0 or -1 as meaning "unlimited". E.g., "set
1184 trace-buffer-size unlimited" is now an alias for "set
1185 trace-buffer-size -1" and "set height unlimited" is now an alias for
1188 * The "set debug symtab-create" debugging option of GDB has been changed to
1189 accept a verbosity level. 0 means "off", 1 provides basic debugging
1190 output, and values of 2 or greater provides more verbose output.
1192 * New command-line options
1194 Display the details of GDB configure-time options.
1196 * The command 'tsave' can now support new option '-ctf' to save trace
1197 buffer in Common Trace Format.
1199 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1202 * GDB now implements the the C++ 'typeid' operator.
1204 * The new convenience variable $_exception holds the exception being
1205 thrown or caught at an exception-related catchpoint.
1207 * The exception-related catchpoints, like "catch throw", now accept a
1208 regular expression which can be used to filter exceptions by type.
1210 * The new convenience variable $_exitsignal is automatically set to
1211 the terminating signal number when the program being debugged dies
1212 due to an uncaught signal.
1216 ** All MI commands now accept an optional "--language" option.
1217 Support for this feature can be verified by using the "-list-features"
1218 command, which should contain "language-option".
1220 ** The new command -info-gdb-mi-command allows the user to determine
1221 whether a GDB/MI command is supported or not.
1223 ** The "^error" result record returned when trying to execute an undefined
1224 GDB/MI command now provides a variable named "code" whose content is the
1225 "undefined-command" error code. Support for this feature can be verified
1226 by using the "-list-features" command, which should contain
1227 "undefined-command-error-code".
1229 ** The -trace-save MI command can optionally save trace buffer in Common
1232 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1234 ** The command -data-list-register-values now accepts an optional
1235 "--skip-unavailable" option. When used, only the available registers
1238 ** The new command -trace-frame-collected dumps collected variables,
1239 computed expressions, tvars, memory and registers in a traceframe.
1241 ** The commands -stack-list-locals, -stack-list-arguments and
1242 -stack-list-variables now accept an option "--skip-unavailable".
1243 When used, only the available locals or arguments are displayed.
1245 ** The -exec-run command now accepts an optional "--start" option.
1246 When used, the command follows the same semantics as the "start"
1247 command, stopping the program's execution at the start of its
1248 main subprogram. Support for this feature can be verified using
1249 the "-list-features" command, which should contain
1250 "exec-run-start-option".
1252 ** The new commands -catch-assert and -catch-exceptions insert
1253 catchpoints stopping the program when Ada exceptions are raised.
1255 ** The new command -info-ada-exceptions provides the equivalent of
1256 the new "info exceptions" command.
1258 * New system-wide configuration scripts
1259 A GDB installation now provides scripts suitable for use as system-wide
1260 configuration scripts for the following systems:
1264 * GDB now supports target-assigned range stepping with remote targets.
1265 This improves the performance of stepping source lines by reducing
1266 the number of control packets from/to GDB. See "New remote packets"
1269 * GDB now understands the element 'tvar' in the XML traceframe info.
1270 It has the id of the collected trace state variables.
1272 * On S/390 targets that provide the transactional-execution feature,
1273 the program interruption transaction diagnostic block (TDB) is now
1274 represented as a number of additional "registers" in GDB.
1276 * New remote packets
1280 The vCont packet supports a new 'r' action, that tells the remote
1281 stub to step through an address range itself, without GDB
1282 involvemement at each single-step.
1284 qXfer:libraries-svr4:read's annex
1285 The previously unused annex of the qXfer:libraries-svr4:read packet
1286 is now used to support passing an argument list. The remote stub
1287 reports support for this argument list to GDB's qSupported query.
1288 The defined arguments are "start" and "prev", used to reduce work
1289 necessary for library list updating, resulting in significant
1292 * New features in the GDB remote stub, GDBserver
1294 ** GDBserver now supports target-assisted range stepping. Currently
1295 enabled on x86/x86_64 GNU/Linux targets.
1297 ** GDBserver now adds element 'tvar' in the XML in the reply to
1298 'qXfer:traceframe-info:read'. It has the id of the collected
1299 trace state variables.
1301 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1304 * New 'z' formatter for printing and examining memory, this displays the
1305 value as hexadecimal zero padded on the left to the size of the type.
1307 * GDB can now use Windows x64 unwinding data.
1309 * The "set remotebaud" command has been replaced by "set serial baud".
1310 Similarly, "show remotebaud" has been replaced by "show serial baud".
1311 The "set remotebaud" and "show remotebaud" commands are still available
1312 to provide backward compatibility with older versions of GDB.
1314 *** Changes in GDB 7.6
1316 * Target record has been renamed to record-full.
1317 Record/replay is now enabled with the "record full" command.
1318 This also affects settings that are associated with full record/replay
1319 that have been moved from "set/show record" to "set/show record full":
1321 set|show record full insn-number-max
1322 set|show record full stop-at-limit
1323 set|show record full memory-query
1325 * A new record target "record-btrace" has been added. The new target
1326 uses hardware support to record the control-flow of a process. It
1327 does not support replaying the execution, but it implements the
1328 below new commands for investigating the recorded execution log.
1329 This new recording method can be enabled using:
1333 The "record-btrace" target is only available on Intel Atom processors
1334 and requires a Linux kernel 2.6.32 or later.
1336 * Two new commands have been added for record/replay to give information
1337 about the recorded execution without having to replay the execution.
1338 The commands are only supported by "record btrace".
1340 record instruction-history prints the execution history at
1341 instruction granularity
1343 record function-call-history prints the execution history at
1344 function granularity
1346 * New native configurations
1348 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1349 FreeBSD/powerpc powerpc*-*-freebsd
1350 x86_64/Cygwin x86_64-*-cygwin*
1351 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1355 ARM AArch64 aarch64*-*-elf
1356 ARM AArch64 GNU/Linux aarch64*-*-linux
1357 Lynx 178 PowerPC powerpc-*-lynx*178
1358 x86_64/Cygwin x86_64-*-cygwin*
1359 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1361 * If the configured location of system.gdbinit file (as given by the
1362 --with-system-gdbinit option at configure time) is in the
1363 data-directory (as specified by --with-gdb-datadir at configure
1364 time) or in one of its subdirectories, then GDB will look for the
1365 system-wide init file in the directory specified by the
1366 --data-directory command-line option.
1368 * New command line options:
1370 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1371 other initialization files, unlike -nx which disables all of them.
1373 * Removed command line options
1375 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1378 * The 'ptype' and 'whatis' commands now accept an argument to control
1381 * 'info proc' now works on some core files.
1385 ** Vectors can be created with gdb.Type.vector.
1387 ** Python's atexit.register now works in GDB.
1389 ** Types can be pretty-printed via a Python API.
1391 ** Python 3 is now supported (in addition to Python 2.4 or later)
1393 ** New class gdb.Architecture exposes GDB's internal representation
1394 of architecture in the Python API.
1396 ** New method Frame.architecture returns the gdb.Architecture object
1397 corresponding to the frame's architecture.
1399 * New Python-based convenience functions:
1401 ** $_memeq(buf1, buf2, length)
1402 ** $_streq(str1, str2)
1404 ** $_regex(str, regex)
1406 * The 'cd' command now defaults to using '~' (the home directory) if not
1409 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1410 default for GCC since November 2000.
1412 * The command 'forward-search' can now be abbreviated as 'fo'.
1414 * The command 'info tracepoints' can now display 'installed on target'
1415 or 'not installed on target' for each non-pending location of tracepoint.
1417 * New configure options
1419 --enable-libmcheck/--disable-libmcheck
1420 By default, development versions are built with -lmcheck on hosts
1421 that support it, in order to help track memory corruption issues.
1422 Release versions, on the other hand, are built without -lmcheck
1423 by default. The --enable-libmcheck/--disable-libmcheck configure
1424 options allow the user to override that default.
1425 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1426 This configure option allows the user to build GDB with
1427 libbabeltrace using which GDB can read Common Trace Format data.
1429 * New commands (for set/show, see "New options" below)
1432 Catch signals. This is similar to "handle", but allows commands and
1433 conditions to be attached.
1436 List the BFDs known to GDB.
1438 python-interactive [command]
1440 Start a Python interactive prompt, or evaluate the optional command
1441 and print the result of expressions.
1444 "py" is a new alias for "python".
1446 enable type-printer [name]...
1447 disable type-printer [name]...
1448 Enable or disable type printers.
1452 ** For the Renesas Super-H architecture, the "regs" command has been removed
1453 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1458 set print type methods (on|off)
1459 show print type methods
1460 Control whether method declarations are displayed by "ptype".
1461 The default is to show them.
1463 set print type typedefs (on|off)
1464 show print type typedefs
1465 Control whether typedef definitions are displayed by "ptype".
1466 The default is to show them.
1468 set filename-display basename|relative|absolute
1469 show filename-display
1470 Control the way in which filenames is displayed.
1471 The default is "relative", which preserves previous behavior.
1473 set trace-buffer-size
1474 show trace-buffer-size
1475 Request target to change the size of trace buffer.
1477 set remote trace-buffer-size-packet auto|on|off
1478 show remote trace-buffer-size-packet
1479 Control the use of the remote protocol `QTBuffer:size' packet.
1483 Control display of debugging messages related to ARM AArch64.
1486 set debug coff-pe-read
1487 show debug coff-pe-read
1488 Control display of debugging messages related to reading of COFF/PE
1493 Control display of debugging messages related to Mach-O symbols
1496 set debug notification
1497 show debug notification
1498 Control display of debugging info for async remote notification.
1502 ** Command parameter changes are now notified using new async record
1503 "=cmd-param-changed".
1504 ** Trace frame changes caused by command "tfind" are now notified using
1505 new async record "=traceframe-changed".
1506 ** The creation, deletion and modification of trace state variables
1507 are now notified using new async records "=tsv-created",
1508 "=tsv-deleted" and "=tsv-modified".
1509 ** The start and stop of process record are now notified using new
1510 async record "=record-started" and "=record-stopped".
1511 ** Memory changes are now notified using new async record
1513 ** The data-disassemble command response will include a "fullname" field
1514 containing the absolute file name when source has been requested.
1515 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1516 command, to allow pattern filling of memory areas.
1517 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1518 library load/unload events.
1519 ** The response to breakpoint commands and breakpoint async records
1520 includes an "installed" field containing a boolean state about each
1521 non-pending tracepoint location is whether installed on target or not.
1522 ** Output of the "-trace-status" command includes a "trace-file" field
1523 containing the name of the trace file being examined. This field is
1524 optional, and only present when examining a trace file.
1525 ** The "fullname" field is now always present along with the "file" field,
1526 even if the file cannot be found by GDB.
1528 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1529 You must have the LZMA library available when configuring GDB for this
1530 feature to be enabled. For more information, see:
1531 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1533 * New remote packets
1536 Set the size of trace buffer. The remote stub reports support for this
1537 packet to gdb's qSupported query.
1540 Enable Branch Trace Store (BTS)-based branch tracing for the current
1541 thread. The remote stub reports support for this packet to gdb's
1545 Disable branch tracing for the current thread. The remote stub reports
1546 support for this packet to gdb's qSupported query.
1549 Read the traced branches for the current thread. The remote stub
1550 reports support for this packet to gdb's qSupported query.
1552 *** Changes in GDB 7.5
1554 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1555 for more x32 ABI info.
1557 * GDB now supports access to MIPS DSP registers on Linux targets.
1559 * GDB now supports debugging microMIPS binaries.
1561 * The "info os" command on GNU/Linux can now display information on
1562 several new classes of objects managed by the operating system:
1563 "info os procgroups" lists process groups
1564 "info os files" lists file descriptors
1565 "info os sockets" lists internet-domain sockets
1566 "info os shm" lists shared-memory regions
1567 "info os semaphores" lists semaphores
1568 "info os msg" lists message queues
1569 "info os modules" lists loaded kernel modules
1571 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1572 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1573 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1574 options and inspect the probe arguments using the new $_probe_arg family
1575 of convenience variables. You can obtain more information about SystemTap
1576 in <http://sourceware.org/systemtap/>.
1578 * GDB now supports reversible debugging on ARM, it allows you to
1579 debug basic ARM and THUMB instructions, and provides
1580 record/replay support.
1582 * The option "symbol-reloading" has been deleted as it is no longer used.
1586 ** GDB commands implemented in Python can now be put in command class
1589 ** The "maint set python print-stack on|off" is now deleted.
1591 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1592 apply "flag enum"-style pretty-printing to any enum.
1594 ** gdb.lookup_symbol can now work when there is no current frame.
1596 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1597 the source at which the symbol was defined.
1599 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1600 method 'value'. The former indicates whether the symbol needs a
1601 frame in order to compute its value, and the latter computes the
1604 ** A new method 'referenced_value' on gdb.Value objects which can
1605 dereference pointer as well as C++ reference values.
1607 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1608 which return the global and static blocks (as gdb.Block objects),
1609 of the underlying symbol table, respectively.
1611 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1612 object associated with a PC value.
1614 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1615 of the address range occupied by code for the current source line.
1617 * Go language support.
1618 GDB now supports debugging programs written in the Go programming
1621 * GDBserver now supports stdio connections.
1622 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1624 * The binary "gdbtui" can no longer be built or installed.
1625 Use "gdb -tui" instead.
1627 * GDB will now print "flag" enums specially. A flag enum is one where
1628 all the enumerator values have no bits in common when pairwise
1629 "and"ed. When printing a value whose type is a flag enum, GDB will
1630 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1631 (gdb) print (enum E) 3
1634 * The filename part of a linespec will now match trailing components
1635 of a source file name. For example, "break gcc/expr.c:1000" will
1636 now set a breakpoint in build/gcc/expr.c, but not
1637 build/libcpp/expr.c.
1639 * The "info proc" and "generate-core-file" commands will now also
1640 work on remote targets connected to GDBserver on Linux.
1642 * The command "info catch" has been removed. It has been disabled
1643 since December 2007.
1645 * The "catch exception" and "catch assert" commands now accept
1646 a condition at the end of the command, much like the "break"
1647 command does. For instance:
1649 (gdb) catch exception Constraint_Error if Barrier = True
1651 Previously, it was possible to add a condition to such catchpoints,
1652 but it had to be done as a second step, after the catchpoint had been
1653 created, using the "condition" command.
1655 * The "info static-tracepoint-marker" command will now also work on
1656 native Linux targets with in-process agent.
1658 * GDB can now set breakpoints on inlined functions.
1660 * The .gdb_index section has been updated to include symbols for
1661 inlined functions. GDB will ignore older .gdb_index sections by
1662 default, which could cause symbol files to be loaded more slowly
1663 until their .gdb_index sections can be recreated. The new command
1664 "set use-deprecated-index-sections on" will cause GDB to use any older
1665 .gdb_index sections it finds. This will restore performance, but the
1666 ability to set breakpoints on inlined functions will be lost in symbol
1667 files with older .gdb_index sections.
1669 The .gdb_index section has also been updated to record more information
1670 about each symbol. This speeds up the "info variables", "info functions"
1671 and "info types" commands when used with programs having the .gdb_index
1672 section, as well as speeding up debugging with shared libraries using
1673 the .gdb_index section.
1675 * Ada support for GDB/MI Variable Objects has been added.
1677 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1682 ** New command -info-os is the MI equivalent of "info os".
1684 ** Output logs ("set logging" and related) now include MI output.
1688 ** "set use-deprecated-index-sections on|off"
1689 "show use-deprecated-index-sections on|off"
1690 Controls the use of deprecated .gdb_index sections.
1692 ** "catch load" and "catch unload" can be used to stop when a shared
1693 library is loaded or unloaded, respectively.
1695 ** "enable count" can be used to auto-disable a breakpoint after
1698 ** "info vtbl" can be used to show the virtual method tables for
1699 C++ and Java objects.
1701 ** "explore" and its sub commands "explore value" and "explore type"
1702 can be used to recursively explore values and types of
1703 expressions. These commands are available only if GDB is
1704 configured with '--with-python'.
1706 ** "info auto-load" shows status of all kinds of auto-loaded files,
1707 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1708 sequences of commands files, "info auto-load python-scripts"
1709 shows status of auto-loading Python script files,
1710 "info auto-load local-gdbinit" shows status of loading init file
1711 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1712 status of inferior specific thread debugging shared library loading.
1714 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1715 and "show auto-load-scripts" commands have been deprecated, use their
1716 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1717 and "show auto-load python-scripts" counterparts instead.
1719 ** "dprintf location,format,args..." creates a dynamic printf, which
1720 is basically a breakpoint that does a printf and immediately
1721 resumes your program's execution, so it is like a printf that you
1722 can insert dynamically at runtime instead of at compiletime.
1724 ** "set print symbol"
1726 Controls whether GDB attempts to display the symbol, if any,
1727 corresponding to addresses it prints. This defaults to "on", but
1728 you can set it to "off" to restore GDB's previous behavior.
1730 * Deprecated commands
1732 ** For the Renesas Super-H architecture, the "regs" command has been
1733 deprecated, and "info all-registers" should be used instead.
1737 Renesas RL78 rl78-*-elf
1738 HP OpenVMS ia64 ia64-hp-openvms*
1740 * GDBserver supports evaluation of breakpoint conditions. When
1741 support is advertised by GDBserver, GDB may be told to send the
1742 breakpoint conditions in bytecode form to GDBserver. GDBserver
1743 will only report the breakpoint trigger to GDB when its condition
1748 set mips compression
1749 show mips compression
1750 Select the compressed ISA encoding used in functions that have no symbol
1751 information available. The encoding can be set to either of:
1754 and is updated automatically from ELF file flags if available.
1756 set breakpoint condition-evaluation
1757 show breakpoint condition-evaluation
1758 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1759 GDBserver ("target"). Default option "auto" chooses the most efficient
1761 This option can improve debugger efficiency depending on the speed of the
1765 Disable auto-loading globally.
1768 Show auto-loading setting of all kinds of auto-loaded files.
1770 set auto-load gdb-scripts on|off
1771 show auto-load gdb-scripts
1772 Control auto-loading of GDB canned sequences of commands files.
1774 set auto-load python-scripts on|off
1775 show auto-load python-scripts
1776 Control auto-loading of Python script files.
1778 set auto-load local-gdbinit on|off
1779 show auto-load local-gdbinit
1780 Control loading of init file (.gdbinit) from current directory.
1782 set auto-load libthread-db on|off
1783 show auto-load libthread-db
1784 Control auto-loading of inferior specific thread debugging shared library.
1786 set auto-load scripts-directory <dir1>[:<dir2>...]
1787 show auto-load scripts-directory
1788 Set a list of directories from which to load auto-loaded scripts.
1789 Automatically loaded Python scripts and GDB scripts are located in one
1790 of the directories listed by this option.
1791 The delimiter (':' above) may differ according to the host platform.
1793 set auto-load safe-path <dir1>[:<dir2>...]
1794 show auto-load safe-path
1795 Set a list of directories from which it is safe to auto-load files.
1796 The delimiter (':' above) may differ according to the host platform.
1798 set debug auto-load on|off
1799 show debug auto-load
1800 Control display of debugging info for auto-loading the files above.
1802 set dprintf-style gdb|call|agent
1804 Control the way in which a dynamic printf is performed; "gdb"
1805 requests a GDB printf command, while "call" causes dprintf to call a
1806 function in the inferior. "agent" requests that the target agent
1807 (such as GDBserver) do the printing.
1809 set dprintf-function <expr>
1810 show dprintf-function
1811 set dprintf-channel <expr>
1812 show dprintf-channel
1813 Set the function and optional first argument to the call when using
1814 the "call" style of dynamic printf.
1816 set disconnected-dprintf on|off
1817 show disconnected-dprintf
1818 Control whether agent-style dynamic printfs continue to be in effect
1819 after GDB disconnects.
1821 * New configure options
1823 --with-auto-load-dir
1824 Configure default value for the 'set auto-load scripts-directory'
1825 setting above. It defaults to '$debugdir:$datadir/auto-load',
1826 $debugdir representing global debugging info directories (available
1827 via 'show debug-file-directory') and $datadir representing GDB's data
1828 directory (available via 'show data-directory').
1830 --with-auto-load-safe-path
1831 Configure default value for the 'set auto-load safe-path' setting
1832 above. It defaults to the --with-auto-load-dir setting.
1834 --without-auto-load-safe-path
1835 Set 'set auto-load safe-path' to '/', effectively disabling this
1838 * New remote packets
1840 z0/z1 conditional breakpoints extension
1842 The z0/z1 breakpoint insertion packets have been extended to carry
1843 a list of conditional expressions over to the remote stub depending on the
1844 condition evaluation mode. The use of this extension can be controlled
1845 via the "set remote conditional-breakpoints-packet" command.
1849 Specify the signals which the remote stub may pass to the debugged
1850 program without GDB involvement.
1852 * New command line options
1854 --init-command=FILE, -ix Like --command, -x but execute it
1855 before loading inferior.
1856 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1857 execute it before loading inferior.
1859 *** Changes in GDB 7.4
1861 * GDB now handles ambiguous linespecs more consistently; the existing
1862 FILE:LINE support has been expanded to other types of linespecs. A
1863 breakpoint will now be set on all matching locations in all
1864 inferiors, and locations will be added or removed according to
1867 * GDB now allows you to skip uninteresting functions and files when
1868 stepping with the "skip function" and "skip file" commands.
1870 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1871 and "show remote hardware-watchpoint-length-limit". These allows to
1872 set or show the maximum length limit (in bytes) of a remote
1873 target hardware watchpoint.
1875 This allows e.g. to use "unlimited" hardware watchpoints with the
1876 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1877 watchpoints are slower than real hardware watchpoints but are
1878 significantly faster than gdb software watchpoints.
1882 ** The register_pretty_printer function in module gdb.printing now takes
1883 an optional `replace' argument. If True, the new printer replaces any
1886 ** The "maint set python print-stack on|off" command has been
1887 deprecated and will be deleted in GDB 7.5.
1888 A new command: "set python print-stack none|full|message" has
1889 replaced it. Additionally, the default for "print-stack" is
1890 now "message", which just prints the error message without
1893 ** A prompt substitution hook (prompt_hook) is now available to the
1896 ** A new Python module, gdb.prompt has been added to the GDB Python
1897 modules library. This module provides functionality for
1898 escape sequences in prompts (used by set/show
1899 extended-prompt). These escape sequences are replaced by their
1900 corresponding value.
1902 ** Python commands and convenience-functions located in
1903 'data-directory'/python/gdb/command and
1904 'data-directory'/python/gdb/function are now automatically loaded
1907 ** Blocks now provide four new attributes. global_block and
1908 static_block will return the global and static blocks
1909 respectively. is_static and is_global are boolean attributes
1910 that indicate if the block is one of those two types.
1912 ** Symbols now provide the "type" attribute, the type of the symbol.
1914 ** The "gdb.breakpoint" function has been deprecated in favor of
1917 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1918 of a function. This class is based on the "finish" command
1919 available in the CLI.
1921 ** Type objects for struct and union types now allow access to
1922 the fields using standard Python dictionary (mapping) methods.
1923 For example, "some_type['myfield']" now works, as does
1924 "some_type.items()".
1926 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1929 ** A new function, "deep_items" has been added to the gdb.types
1930 module in the GDB Python modules library. This function returns
1931 an iterator over the fields of a struct or union type. Unlike
1932 the standard Python "iteritems" method, it will recursively traverse
1933 any anonymous fields.
1937 ** "*stopped" events can report several new "reason"s, such as
1940 ** Breakpoint changes are now notified using new async records, like
1941 "=breakpoint-modified".
1943 ** New command -ada-task-info.
1945 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1946 $sdir specifies the default system locations of shared libraries.
1947 $pdir specifies the directory where the libpthread used by the application
1950 GDB no longer looks in $sdir and $pdir after it has searched the directories
1951 mentioned in libthread-db-search-path. If you want to search those
1952 directories, they must be specified in libthread-db-search-path.
1953 The default value of libthread-db-search-path on GNU/Linux and Solaris
1954 systems is now "$sdir:$pdir".
1956 $pdir is not supported by gdbserver, it is currently ignored.
1957 $sdir is supported by gdbserver.
1959 * New configure option --with-iconv-bin.
1960 When using the internationalization support like the one in the GNU C
1961 library, GDB will invoke the "iconv" program to get a list of supported
1962 character sets. If this program lives in a non-standard location, one can
1963 use this option to specify where to find it.
1965 * When natively debugging programs on PowerPC BookE processors running
1966 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1967 watchpoints, which specify a mask in addition to an address to watch.
1968 The mask specifies that some bits of an address (the bits which are
1969 reset in the mask) should be ignored when matching the address accessed
1970 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1971 section in the user manual for more details.
1973 * The new option --once causes GDBserver to stop listening for connections once
1974 the first connection is made. The listening port used by GDBserver will
1975 become available after that.
1977 * New commands "info macros" and "alias" have been added.
1979 * New function parameters suffix @entry specifies value of function parameter
1980 at the time the function got called. Entry values are available only since
1986 "!" is now an alias of the "shell" command.
1987 Note that no space is needed between "!" and SHELL COMMAND.
1991 watch EXPRESSION mask MASK_VALUE
1992 The watch command now supports the mask argument which allows creation
1993 of masked watchpoints, if the current architecture supports this feature.
1995 info auto-load-scripts [REGEXP]
1996 This command was formerly named "maintenance print section-scripts".
1997 It is now generally useful and is no longer a maintenance-only command.
1999 info macro [-all] [--] MACRO
2000 The info macro command has new options `-all' and `--'. The first for
2001 printing all definitions of a macro. The second for explicitly specifying
2002 the end of arguments and the beginning of the macro name in case the macro
2003 name starts with a hyphen.
2005 collect[/s] EXPRESSIONS
2006 The tracepoint collect command now takes an optional modifier "/s"
2007 that directs it to dereference pointer-to-character types and
2008 collect the bytes of memory up to a zero byte. The behavior is
2009 similar to what you see when you use the regular print command on a
2010 string. An optional integer following the "/s" sets a bound on the
2011 number of bytes that will be collected.
2014 The trace start command now interprets any supplied arguments as a
2015 note to be recorded with the trace run, with an effect similar to
2016 setting the variable trace-notes.
2019 The trace stop command now interprets any arguments as a note to be
2020 mentioned along with the tstatus report that the trace was stopped
2021 with a command. The effect is similar to setting the variable
2024 * Tracepoints can now be enabled and disabled at any time after a trace
2025 experiment has been started using the standard "enable" and "disable"
2026 commands. It is now possible to start a trace experiment with no enabled
2027 tracepoints; GDB will display a warning, but will allow the experiment to
2028 begin, assuming that tracepoints will be enabled as needed while the trace
2031 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2032 locations with 4-byte instructions, when they were previously
2033 limited to locations with instructions of 5 bytes or longer.
2037 set debug dwarf2-read
2038 show debug dwarf2-read
2039 Turns on or off display of debugging messages related to reading
2040 DWARF debug info. The default is off.
2042 set debug symtab-create
2043 show debug symtab-create
2044 Turns on or off display of debugging messages related to symbol table
2045 creation. The default is off.
2048 show extended-prompt
2049 Set the GDB prompt, and allow escape sequences to be inserted to
2050 display miscellaneous information (see 'help set extended-prompt'
2051 for the list of sequences). This prompt (and any information
2052 accessed through the escape sequences) is updated every time the
2053 prompt is displayed.
2055 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2056 show print entry-values
2057 Set printing of frame argument values at function entry. In some cases
2058 GDB can determine the value of function argument which was passed by the
2059 function caller, even if the value was modified inside the called function.
2061 set debug entry-values
2062 show debug entry-values
2063 Control display of debugging info for determining frame argument values at
2064 function entry and virtual tail call frames.
2066 set basenames-may-differ
2067 show basenames-may-differ
2068 Set whether a source file may have multiple base names.
2069 (A "base name" is the name of a file with the directory part removed.
2070 Example: The base name of "/home/user/hello.c" is "hello.c".)
2071 If set, GDB will canonicalize file names (e.g., expand symlinks)
2072 before comparing them. Canonicalization is an expensive operation,
2073 but it allows the same file be known by more than one base name.
2074 If not set (the default), all source files are assumed to have just
2075 one base name, and gdb will do file name comparisons more efficiently.
2081 Set a user name and notes for the current and any future trace runs.
2082 This is useful for long-running and/or disconnected traces, to
2083 inform others (or yourself) as to who is running the trace, supply
2084 contact information, or otherwise explain what is going on.
2086 set trace-stop-notes
2087 show trace-stop-notes
2088 Set a note attached to the trace run, that is displayed when the
2089 trace has been stopped by a tstop command. This is useful for
2090 instance as an explanation, if you are stopping a trace run that was
2091 started by someone else.
2093 * New remote packets
2097 Dynamically enable a tracepoint in a started trace experiment.
2101 Dynamically disable a tracepoint in a started trace experiment.
2105 Set the user and notes of the trace run.
2109 Query the current status of a tracepoint.
2113 Query the minimum length of instruction at which a fast tracepoint may
2116 * Dcache size (number of lines) and line-size are now runtime-configurable
2117 via "set dcache line" and "set dcache line-size" commands.
2121 Texas Instruments TMS320C6x tic6x-*-*
2125 Renesas RL78 rl78-*-elf
2127 *** Changes in GDB 7.3.1
2129 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2131 *** Changes in GDB 7.3
2133 * GDB has a new command: "thread find [REGEXP]".
2134 It finds the thread id whose name, target id, or thread extra info
2135 matches the given regular expression.
2137 * The "catch syscall" command now works on mips*-linux* targets.
2139 * The -data-disassemble MI command now supports modes 2 and 3 for
2140 dumping the instruction opcodes.
2142 * New command line options
2144 -data-directory DIR Specify DIR as the "data-directory".
2145 This is mostly for testing purposes.
2147 * The "maint set python auto-load on|off" command has been renamed to
2148 "set auto-load-scripts on|off".
2150 * GDB has a new command: "set directories".
2151 It is like the "dir" command except that it replaces the
2152 source path list instead of augmenting it.
2154 * GDB now understands thread names.
2156 On GNU/Linux, "info threads" will display the thread name as set by
2157 prctl or pthread_setname_np.
2159 There is also a new command, "thread name", which can be used to
2160 assign a name internally for GDB to display.
2163 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2164 has been integrated into GDB.
2168 ** The function gdb.Write now accepts an optional keyword 'stream'.
2169 This keyword, when provided, will direct the output to either
2170 stdout, stderr, or GDB's logging output.
2172 ** Parameters can now be be sub-classed in Python, and in particular
2173 you may implement the get_set_doc and get_show_doc functions.
2174 This improves how Parameter set/show documentation is processed
2175 and allows for more dynamic content.
2177 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2178 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2179 have an is_valid method.
2181 ** Breakpoints can now be sub-classed in Python, and in particular
2182 you may implement a 'stop' function that is executed each time
2183 the inferior reaches that breakpoint.
2185 ** New function gdb.lookup_global_symbol looks up a global symbol.
2187 ** GDB values in Python are now callable if the value represents a
2188 function. For example, if 'some_value' represents a function that
2189 takes two integer parameters and returns a value, you can call
2190 that function like so:
2192 result = some_value (10,20)
2194 ** Module gdb.types has been added.
2195 It contains a collection of utilities for working with gdb.Types objects:
2196 get_basic_type, has_field, make_enum_dict.
2198 ** Module gdb.printing has been added.
2199 It contains utilities for writing and registering pretty-printers.
2200 New classes: PrettyPrinter, SubPrettyPrinter,
2201 RegexpCollectionPrettyPrinter.
2202 New function: register_pretty_printer.
2204 ** New commands "info pretty-printers", "enable pretty-printer" and
2205 "disable pretty-printer" have been added.
2207 ** gdb.parameter("directories") is now available.
2209 ** New function gdb.newest_frame returns the newest frame in the
2212 ** The gdb.InferiorThread class has a new "name" attribute. This
2213 holds the thread's name.
2215 ** Python Support for Inferior events.
2216 Python scripts can add observers to be notified of events
2217 occurring in the process being debugged.
2218 The following events are currently supported:
2219 - gdb.events.cont Continue event.
2220 - gdb.events.exited Inferior exited event.
2221 - gdb.events.stop Signal received, and Breakpoint hit events.
2225 ** GDB now puts template parameters in scope when debugging in an
2226 instantiation. For example, if you have:
2228 template<int X> int func (void) { return X; }
2230 then if you step into func<5>, "print X" will show "5". This
2231 feature requires proper debuginfo support from the compiler; it
2232 was added to GCC 4.5.
2234 ** The motion commands "next", "finish", "until", and "advance" now
2235 work better when exceptions are thrown. In particular, GDB will
2236 no longer lose control of the inferior; instead, the GDB will
2237 stop the inferior at the point at which the exception is caught.
2238 This functionality requires a change in the exception handling
2239 code that was introduced in GCC 4.5.
2241 * GDB now follows GCC's rules on accessing volatile objects when
2242 reading or writing target state during expression evaluation.
2243 One notable difference to prior behavior is that "print x = 0"
2244 no longer generates a read of x; the value of the assignment is
2245 now always taken directly from the value being assigned.
2247 * GDB now has some support for using labels in the program's source in
2248 linespecs. For instance, you can use "advance label" to continue
2249 execution to a label.
2251 * GDB now has support for reading and writing a new .gdb_index
2252 section. This section holds a fast index of DWARF debugging
2253 information and can be used to greatly speed up GDB startup and
2254 operation. See the documentation for `save gdb-index' for details.
2256 * The "watch" command now accepts an optional "-location" argument.
2257 When used, this causes GDB to watch the memory referred to by the
2258 expression. Such a watchpoint is never deleted due to it going out
2261 * GDB now supports thread debugging of core dumps on GNU/Linux.
2263 GDB now activates thread debugging using the libthread_db library
2264 when debugging GNU/Linux core dumps, similarly to when debugging
2265 live processes. As a result, when debugging a core dump file, GDB
2266 is now able to display pthread_t ids of threads. For example, "info
2267 threads" shows the same output as when debugging the process when it
2268 was live. In earlier releases, you'd see something like this:
2271 * 1 LWP 6780 main () at main.c:10
2273 While now you see this:
2276 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2278 It is also now possible to inspect TLS variables when debugging core
2281 When debugging a core dump generated on a machine other than the one
2282 used to run GDB, you may need to point GDB at the correct
2283 libthread_db library with the "set libthread-db-search-path"
2284 command. See the user manual for more details on this command.
2286 * When natively debugging programs on PowerPC BookE processors running
2287 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2288 which stop execution of the inferior whenever it executes an instruction
2289 at any address within the specified range. See the "PowerPC Embedded"
2290 section in the user manual for more details.
2292 * New features in the GDB remote stub, GDBserver
2294 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2295 and i686 LynxOS (version 5.x).
2297 ** GDBserver is now supported on Blackfin Linux.
2299 * New native configurations
2301 ia64 HP-UX ia64-*-hpux*
2305 Analog Devices, Inc. Blackfin Processor bfin-*
2307 * Ada task switching is now supported on sparc-elf targets when
2308 debugging a program using the Ravenscar Profile. For more information,
2309 see the "Tasking Support when using the Ravenscar Profile" section
2310 in the GDB user manual.
2312 * Guile support was removed.
2314 * New features in the GNU simulator
2316 ** The --map-info flag lists all known core mappings.
2318 ** CFI flashes may be simulated via the "cfi" device.
2320 *** Changes in GDB 7.2
2322 * Shared library support for remote targets by default
2324 When GDB is configured for a generic, non-OS specific target, like
2325 for example, --target=arm-eabi or one of the many *-*-elf targets,
2326 GDB now queries remote stubs for loaded shared libraries using the
2327 `qXfer:libraries:read' packet. Previously, shared library support
2328 was always disabled for such configurations.
2332 ** Argument Dependent Lookup (ADL)
2334 In C++ ADL lookup directs function search to the namespaces of its
2335 arguments even if the namespace has not been imported.
2345 Here the compiler will search for `foo' in the namespace of 'b'
2346 and find A::foo. GDB now supports this. This construct is commonly
2347 used in the Standard Template Library for operators.
2349 ** Improved User Defined Operator Support
2351 In addition to member operators, GDB now supports lookup of operators
2352 defined in a namespace and imported with a `using' directive, operators
2353 defined in the global scope, operators imported implicitly from an
2354 anonymous namespace, and the ADL operators mentioned in the previous
2356 GDB now also supports proper overload resolution for all the previously
2357 mentioned flavors of operators.
2359 ** static const class members
2361 Printing of static const class members that are initialized in the
2362 class definition has been fixed.
2364 * Windows Thread Information Block access.
2366 On Windows targets, GDB now supports displaying the Windows Thread
2367 Information Block (TIB) structure. This structure is visible either
2368 by using the new command `info w32 thread-information-block' or, by
2369 dereferencing the new convenience variable named `$_tlb', a
2370 thread-specific pointer to the TIB. This feature is also supported
2371 when remote debugging using GDBserver.
2373 * Static tracepoints
2375 Static tracepoints are calls in the user program into a tracing
2376 library. One such library is a port of the LTTng kernel tracer to
2377 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2378 When debugging with GDBserver, GDB now supports combining the GDB
2379 tracepoint machinery with such libraries. For example: the user can
2380 use GDB to probe a static tracepoint marker (a call from the user
2381 program into the tracing library) with the new "strace" command (see
2382 "New commands" below). This creates a "static tracepoint" in the
2383 breakpoint list, that can be manipulated with the same feature set
2384 as fast and regular tracepoints. E.g., collect registers, local and
2385 global variables, collect trace state variables, and define
2386 tracepoint conditions. In addition, the user can collect extra
2387 static tracepoint marker specific data, by collecting the new
2388 $_sdata internal variable. When analyzing the trace buffer, you can
2389 inspect $_sdata like any other variable available to GDB. For more
2390 information, see the "Tracepoints" chapter in GDB user manual. New
2391 remote packets have been defined to support static tracepoints, see
2392 the "New remote packets" section below.
2394 * Better reconstruction of tracepoints after disconnected tracing
2396 GDB will attempt to download the original source form of tracepoint
2397 definitions when starting a trace run, and then will upload these
2398 upon reconnection to the target, resulting in a more accurate
2399 reconstruction of the tracepoints that are in use on the target.
2403 You can now exercise direct control over the ways that GDB can
2404 affect your program. For instance, you can disallow the setting of
2405 breakpoints, so that the program can run continuously (assuming
2406 non-stop mode). In addition, the "observer" variable is available
2407 to switch all of the different controls; in observer mode, GDB
2408 cannot affect the target's behavior at all, which is useful for
2409 tasks like diagnosing live systems in the field.
2411 * The new convenience variable $_thread holds the number of the
2414 * New remote packets
2418 Return the address of the Windows Thread Information Block of a given thread.
2422 In response to several of the tracepoint packets, the target may now
2423 also respond with a number of intermediate `qRelocInsn' request
2424 packets before the final result packet, to have GDB handle
2425 relocating an instruction to execute at a different address. This
2426 is particularly useful for stubs that support fast tracepoints. GDB
2427 reports support for this feature in the qSupported packet.
2431 List static tracepoint markers in the target program.
2435 List static tracepoint markers at a given address in the target
2438 qXfer:statictrace:read
2440 Read the static trace data collected (by a `collect $_sdata'
2441 tracepoint action). The remote stub reports support for this packet
2442 to gdb's qSupported query.
2446 Send the current settings of GDB's permission flags.
2450 Send part of the source (textual) form of a tracepoint definition,
2451 which includes location, conditional, and action list.
2453 * The source command now accepts a -s option to force searching for the
2454 script in the source search path even if the script name specifies
2457 * New features in the GDB remote stub, GDBserver
2459 - GDBserver now support tracepoints (including fast tracepoints, and
2460 static tracepoints). The feature is currently supported by the
2461 i386-linux and amd64-linux builds. See the "Tracepoints support
2462 in gdbserver" section in the manual for more information.
2464 GDBserver JIT compiles the tracepoint's conditional agent
2465 expression bytecode into native code whenever possible for low
2466 overhead dynamic tracepoints conditionals. For such tracepoints,
2467 an expression that examines program state is evaluated when the
2468 tracepoint is reached, in order to determine whether to capture
2469 trace data. If the condition is simple and false, processing the
2470 tracepoint finishes very quickly and no data is gathered.
2472 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2473 for static tracepoints support.
2475 - GDBserver now supports x86_64 Windows 64-bit debugging.
2477 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2478 it understands register description.
2480 * The --batch flag now disables pagination and queries.
2482 * X86 general purpose registers
2484 GDB now supports reading/writing byte, word and double-word x86
2485 general purpose registers directly. This means you can use, say,
2486 $ah or $ax to refer, respectively, to the byte register AH and
2487 16-bit word register AX that are actually portions of the 32-bit
2488 register EAX or 64-bit register RAX.
2490 * The `commands' command now accepts a range of breakpoints to modify.
2491 A plain `commands' following a command that creates multiple
2492 breakpoints affects all the breakpoints set by that command. This
2493 applies to breakpoints set by `rbreak', and also applies when a
2494 single `break' command creates multiple breakpoints (e.g.,
2495 breakpoints on overloaded c++ functions).
2497 * The `rbreak' command now accepts a filename specification as part of
2498 its argument, limiting the functions selected by the regex to those
2499 in the specified file.
2501 * Support for remote debugging Windows and SymbianOS shared libraries
2502 from Unix hosts has been improved. Non Windows GDB builds now can
2503 understand target reported file names that follow MS-DOS based file
2504 system semantics, such as file names that include drive letters and
2505 use the backslash character as directory separator. This makes it
2506 possible to transparently use the "set sysroot" and "set
2507 solib-search-path" on Unix hosts to point as host copies of the
2508 target's shared libraries. See the new command "set
2509 target-file-system-kind" described below, and the "Commands to
2510 specify files" section in the user manual for more information.
2514 eval template, expressions...
2515 Convert the values of one or more expressions under the control
2516 of the string template to a command line, and call it.
2518 set target-file-system-kind unix|dos-based|auto
2519 show target-file-system-kind
2520 Set or show the assumed file system kind for target reported file
2523 save breakpoints <filename>
2524 Save all current breakpoint definitions to a file suitable for use
2525 in a later debugging session. To read the saved breakpoint
2526 definitions, use the `source' command.
2528 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2531 info static-tracepoint-markers
2532 Display information about static tracepoint markers in the target.
2534 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2535 Define a static tracepoint by probing a marker at the given
2536 function, line, address, or marker ID.
2540 Enable and disable observer mode.
2542 set may-write-registers on|off
2543 set may-write-memory on|off
2544 set may-insert-breakpoints on|off
2545 set may-insert-tracepoints on|off
2546 set may-insert-fast-tracepoints on|off
2547 set may-interrupt on|off
2548 Set individual permissions for GDB effects on the target. Note that
2549 some of these settings can have undesirable or surprising
2550 consequences, particularly when changed in the middle of a session.
2551 For instance, disabling the writing of memory can prevent
2552 breakpoints from being inserted, cause single-stepping to fail, or
2553 even crash your program, if you disable after breakpoints have been
2554 inserted. However, GDB should not crash.
2556 set record memory-query on|off
2557 show record memory-query
2558 Control whether to stop the inferior if memory changes caused
2559 by an instruction cannot be recorded.
2564 The disassemble command now supports "start,+length" form of two arguments.
2568 ** GDB now provides a new directory location, called the python directory,
2569 where Python scripts written for GDB can be installed. The location
2570 of that directory is <data-directory>/python, where <data-directory>
2571 is the GDB data directory. For more details, see section `Scripting
2572 GDB using Python' in the manual.
2574 ** The GDB Python API now has access to breakpoints, symbols, symbol
2575 tables, program spaces, inferiors, threads and frame's code blocks.
2576 Additionally, GDB Parameters can now be created from the API, and
2577 manipulated via set/show in the CLI.
2579 ** New functions gdb.target_charset, gdb.target_wide_charset,
2580 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2582 ** New exception gdb.GdbError.
2584 ** Pretty-printers are now also looked up in the current program space.
2586 ** Pretty-printers can now be individually enabled and disabled.
2588 ** GDB now looks for names of Python scripts to auto-load in a
2589 special section named `.debug_gdb_scripts', in addition to looking
2590 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2592 * Tracepoint actions were unified with breakpoint commands. In particular,
2593 there are no longer differences in "info break" output for breakpoints and
2594 tracepoints and the "commands" command can be used for both tracepoints and
2595 regular breakpoints.
2599 ARM Symbian arm*-*-symbianelf*
2601 * D language support.
2602 GDB now supports debugging programs written in the D programming
2605 * GDB now supports the extended ptrace interface for PowerPC which is
2606 available since Linux kernel version 2.6.34. This automatically enables
2607 any hardware breakpoints and additional hardware watchpoints available in
2608 the processor. The old ptrace interface exposes just one hardware
2609 watchpoint and no hardware breakpoints.
2611 * GDB is now able to use the Data Value Compare (DVC) register available on
2612 embedded PowerPC processors to implement in hardware simple watchpoint
2613 conditions of the form:
2615 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2617 This works in native GDB running on Linux kernels with the extended ptrace
2618 interface mentioned above.
2620 *** Changes in GDB 7.1
2624 ** Namespace Support
2626 GDB now supports importing of namespaces in C++. This enables the
2627 user to inspect variables from imported namespaces. Support for
2628 namepace aliasing has also been added. So, if a namespace is
2629 aliased in the current scope (e.g. namepace C=A; ) the user can
2630 print variables using the alias (e.g. (gdb) print C::x).
2634 All known bugs relating to the printing of virtual base class were
2635 fixed. It is now possible to call overloaded static methods using a
2640 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2641 and reinterpret_cast<> are now handled by the C++ expression parser.
2645 Xilinx MicroBlaze microblaze-*-*
2650 Xilinx MicroBlaze microblaze
2653 * Multi-program debugging.
2655 GDB now has support for multi-program (a.k.a. multi-executable or
2656 multi-exec) debugging. This allows for debugging multiple inferiors
2657 simultaneously each running a different program under the same GDB
2658 session. See "Debugging Multiple Inferiors and Programs" in the
2659 manual for more information. This implied some user visible changes
2660 in the multi-inferior support. For example, "info inferiors" now
2661 lists inferiors that are not running yet or that have exited
2662 already. See also "New commands" and "New options" below.
2664 * New tracing features
2666 GDB's tracepoint facility now includes several new features:
2668 ** Trace state variables
2670 GDB tracepoints now include support for trace state variables, which
2671 are variables managed by the target agent during a tracing
2672 experiment. They are useful for tracepoints that trigger each
2673 other, so for instance one tracepoint can count hits in a variable,
2674 and then a second tracepoint has a condition that is true when the
2675 count reaches a particular value. Trace state variables share the
2676 $-syntax of GDB convenience variables, and can appear in both
2677 tracepoint actions and condition expressions. Use the "tvariable"
2678 command to create, and "info tvariables" to view; see "Trace State
2679 Variables" in the manual for more detail.
2683 GDB now includes an option for defining fast tracepoints, which
2684 targets may implement more efficiently, such as by installing a jump
2685 into the target agent rather than a trap instruction. The resulting
2686 speedup can be by two orders of magnitude or more, although the
2687 tradeoff is that some program locations on some target architectures
2688 might not allow fast tracepoint installation, for instance if the
2689 instruction to be replaced is shorter than the jump. To request a
2690 fast tracepoint, use the "ftrace" command, with syntax identical to
2691 the regular trace command.
2693 ** Disconnected tracing
2695 It is now possible to detach GDB from the target while it is running
2696 a trace experiment, then reconnect later to see how the experiment
2697 is going. In addition, a new variable disconnected-tracing lets you
2698 tell the target agent whether to continue running a trace if the
2699 connection is lost unexpectedly.
2703 GDB now has the ability to save the trace buffer into a file, and
2704 then use that file as a target, similarly to you can do with
2705 corefiles. You can select trace frames, print data that was
2706 collected in them, and use tstatus to display the state of the
2707 tracing run at the moment that it was saved. To create a trace
2708 file, use "tsave <filename>", and to use it, do "target tfile
2711 ** Circular trace buffer
2713 You can ask the target agent to handle the trace buffer as a
2714 circular buffer, discarding the oldest trace frames to make room for
2715 newer ones, by setting circular-trace-buffer to on. This feature may
2716 not be available for all target agents.
2721 The disassemble command, when invoked with two arguments, now requires
2722 the arguments to be comma-separated.
2725 The info variables command now displays variable definitions. Files
2726 which only declare a variable are not shown.
2729 The source command is now capable of sourcing Python scripts.
2730 This feature is dependent on the debugger being build with Python
2733 Related to this enhancement is also the introduction of a new command
2734 "set script-extension" (see below).
2736 * New commands (for set/show, see "New options" below)
2738 record save [<FILENAME>]
2739 Save a file (in core file format) containing the process record
2740 execution log for replay debugging at a later time.
2742 record restore <FILENAME>
2743 Restore the process record execution log that was saved at an
2744 earlier time, for replay debugging.
2746 add-inferior [-copies <N>] [-exec <FILENAME>]
2749 clone-inferior [-copies <N>] [ID]
2750 Make a new inferior ready to execute the same program another
2751 inferior has loaded.
2756 maint info program-spaces
2757 List the program spaces loaded into GDB.
2759 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2760 show remote interrupt-sequence
2761 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2762 as the sequence to the remote target in order to interrupt the execution.
2763 Ctrl-C is a default. Some system prefers BREAK which is high level of
2764 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2765 Magic SysRq g. It is BREAK signal and character 'g'.
2767 set remote interrupt-on-connect [on | off]
2768 show remote interrupt-on-connect
2769 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2770 remote target when gdb connects to it. This is needed when you debug
2773 set remotebreak [on | off]
2775 Deprecated. Use "set/show remote interrupt-sequence" instead.
2777 tvariable $NAME [ = EXP ]
2778 Create or modify a trace state variable.
2781 List trace state variables and their values.
2783 delete tvariable $NAME ...
2784 Delete one or more trace state variables.
2787 Evaluate the given expressions without collecting anything into the
2788 trace buffer. (Valid in tracepoint actions only.)
2790 ftrace FN / FILE:LINE / *ADDR
2791 Define a fast tracepoint at the given function, line, or address.
2793 * New expression syntax
2795 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2796 GDB now parses 0b101010 identically with 42.
2800 set follow-exec-mode new|same
2801 show follow-exec-mode
2802 Control whether GDB reuses the same inferior across an exec call or
2803 creates a new one. This is useful to be able to restart the old
2804 executable after the inferior having done an exec call.
2806 set default-collect EXPR, ...
2807 show default-collect
2808 Define a list of expressions to be collected at each tracepoint.
2809 This is a useful way to ensure essential items are not overlooked,
2810 such as registers or a critical global variable.
2812 set disconnected-tracing
2813 show disconnected-tracing
2814 If set to 1, the target is instructed to continue tracing if it
2815 loses its connection to GDB. If 0, the target is to stop tracing
2818 set circular-trace-buffer
2819 show circular-trace-buffer
2820 If set to on, the target is instructed to use a circular trace buffer
2821 and discard the oldest trace frames instead of stopping the trace due
2822 to a full trace buffer. If set to off, the trace stops when the buffer
2823 fills up. Some targets may not support this.
2825 set script-extension off|soft|strict
2826 show script-extension
2827 If set to "off", the debugger does not perform any script language
2828 recognition, and all sourced files are assumed to be GDB scripts.
2829 If set to "soft" (the default), files are sourced according to
2830 filename extension, falling back to GDB scripts if the first
2832 If set to "strict", files are sourced according to filename extension.
2834 set ada trust-PAD-over-XVS on|off
2835 show ada trust-PAD-over-XVS
2836 If off, activate a workaround against a bug in the debugging information
2837 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
2838 the GCC sources for more information about the GNAT encoding and
2839 PAD types in particular). It is always safe to set this option to
2840 off, but this introduces a slight performance penalty. The default
2843 * Python API Improvements
2845 ** GDB provides the new class gdb.LazyString. This is useful in
2846 some pretty-printing cases. The new method gdb.Value.lazy_string
2847 provides a simple way to create objects of this type.
2849 ** The fields returned by gdb.Type.fields now have an
2850 `is_base_class' attribute.
2852 ** The new method gdb.Type.range returns the range of an array type.
2854 ** The new method gdb.parse_and_eval can be used to parse and
2855 evaluate an expression.
2857 * New remote packets
2860 Define a trace state variable.
2863 Get the current value of a trace state variable.
2866 Set desired tracing behavior upon disconnection.
2869 Set the trace buffer to be linear or circular.
2872 Get data about the tracepoints currently in use.
2876 Process record now works correctly with hardware watchpoints.
2878 Multiple bug fixes have been made to the mips-irix port, making it
2879 much more reliable. In particular:
2880 - Debugging threaded applications is now possible again. Previously,
2881 GDB would hang while starting the program, or while waiting for
2882 the program to stop at a breakpoint.
2883 - Attaching to a running process no longer hangs.
2884 - An error occurring while loading a core file has been fixed.
2885 - Changing the value of the PC register now works again. This fixes
2886 problems observed when using the "jump" command, or when calling
2887 a function from GDB, or even when assigning a new value to $pc.
2888 - With the "finish" and "return" commands, the return value for functions
2889 returning a small array is now correctly printed.
2890 - It is now possible to break on shared library code which gets executed
2891 during a shared library init phase (code executed while executing
2892 their .init section). Previously, the breakpoint would have no effect.
2893 - GDB is now able to backtrace through the signal handler for
2894 non-threaded programs.
2896 PIE (Position Independent Executable) programs debugging is now supported.
2897 This includes debugging execution of PIC (Position Independent Code) shared
2898 libraries although for that, it should be possible to run such libraries as an
2901 *** Changes in GDB 7.0
2903 * GDB now has an interface for JIT compilation. Applications that
2904 dynamically generate code can create symbol files in memory and register
2905 them with GDB. For users, the feature should work transparently, and
2906 for JIT developers, the interface is documented in the GDB manual in the
2907 "JIT Compilation Interface" chapter.
2909 * Tracepoints may now be conditional. The syntax is as for
2910 breakpoints; either an "if" clause appended to the "trace" command,
2911 or the "condition" command is available. GDB sends the condition to
2912 the target for evaluation using the same bytecode format as is used
2913 for tracepoint actions.
2915 * The disassemble command now supports: an optional /r modifier, print the
2916 raw instructions in hex as well as in symbolic form, and an optional /m
2917 modifier to print mixed source+assembly.
2919 * Process record and replay
2921 In a architecture environment that supports ``process record and
2922 replay'', ``process record and replay'' target can record a log of
2923 the process execution, and replay it with both forward and reverse
2926 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2927 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2928 set execution-direction {forward|reverse}, for targets that support
2931 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2932 feature is available with a native GDB running on kernel version
2935 * GDB now has support for multi-byte and wide character sets on the
2936 target. Strings whose character type is wchar_t, char16_t, or
2937 char32_t are now correctly printed. GDB supports wide- and unicode-
2938 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2939 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2940 `printf'. This feature requires iconv to work properly; if your
2941 system does not have a working iconv, GDB can use GNU libiconv. See
2942 the installation instructions for more information.
2944 * GDB now supports automatic retrieval of shared library files from
2945 remote targets. To use this feature, specify a system root that begins
2946 with the `remote:' prefix, either via the `set sysroot' command or via
2947 the `--with-sysroot' configure-time option.
2949 * "info sharedlibrary" now takes an optional regex of libraries to show,
2950 and it now reports if a shared library has no debugging information.
2952 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2953 now complete on file names.
2955 * When completing in expressions, gdb will attempt to limit
2956 completions to allowable structure or union fields, where appropriate.
2957 For instance, consider:
2959 # struct example { int f1; double f2; };
2960 # struct example variable;
2963 If the user types TAB at the end of this command line, the available
2964 completions will be "f1" and "f2".
2966 * Inlined functions are now supported. They show up in backtraces, and
2967 the "step", "next", and "finish" commands handle them automatically.
2969 * GDB now supports the token-splicing (##) and stringification (#)
2970 operators when expanding macros. It also supports variable-arity
2973 * GDB now supports inspecting extra signal information, exported by
2974 the new $_siginfo convenience variable. The feature is currently
2975 implemented on linux ARM, i386 and amd64.
2977 * GDB can now display the VFP floating point registers and NEON vector
2978 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2979 can provide these registers (requires Linux 2.6.30 or later). Remote
2980 and simulator targets may also provide them.
2982 * New remote packets
2985 Search memory for a sequence of bytes.
2988 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2989 operation over reliable transport links. Use of this packet is
2990 controlled by the `set remote noack-packet' command.
2993 Kill the process with the specified process ID. Use this in preference
2994 to `k' when multiprocess protocol extensions are supported.
2997 Obtains additional operating system information
3001 Read or write additional signal information.
3003 * Removed remote protocol undocumented extension
3005 An undocumented extension to the remote protocol's `S' stop reply
3006 packet that permited the stub to pass a process id was removed.
3007 Remote servers should use the `T' stop reply packet instead.
3009 * GDB now supports multiple function calling conventions according to the
3010 DWARF-2 DW_AT_calling_convention function attribute.
3012 * The SH target utilizes the aforementioned change to distinguish between gcc
3013 and Renesas calling convention. It also adds the new CLI commands
3014 `set/show sh calling-convention'.
3016 * GDB can now read compressed debug sections, as produced by GNU gold
3017 with the --compress-debug-sections=zlib flag.
3019 * 64-bit core files are now supported on AIX.
3021 * Thread switching is now supported on Tru64.
3023 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3024 which will be allocated using malloc later in program execution.
3026 * The qXfer:libraries:read remote procotol packet now allows passing a
3027 list of section offsets.
3029 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3030 conditions handling signals delivered during attach or thread creation
3031 have also been fixed.
3033 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3034 From the user's standpoint, all unqualified instances of True and False
3035 are treated as the standard definitions, regardless of context.
3037 * GDB now parses C++ symbol and type names more flexibly. For
3040 template<typename T> class C { };
3043 GDB will now correctly handle all of:
3045 ptype C<char const *>
3046 ptype C<char const*>
3047 ptype C<const char *>
3048 ptype C<const char*>
3050 * New features in the GDB remote stub, gdbserver
3052 - The "--wrapper" command-line argument tells gdbserver to use a
3053 wrapper program to launch programs for debugging.
3055 - On PowerPC and S/390 targets, it is now possible to use a single
3056 gdbserver executable to debug both 32-bit and 64-bit programs.
3057 (This requires gdbserver itself to be built as a 64-bit executable.)
3059 - gdbserver uses the new noack protocol mode for TCP connections to
3060 reduce communications latency, if also supported and enabled in GDB.
3062 - Support for the sparc64-linux-gnu target is now included in
3065 - The amd64-linux build of gdbserver now supports debugging both
3066 32-bit and 64-bit programs.
3068 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3069 now support hardware watchpoints, and will use them automatically
3074 GDB now has support for scripting using Python. Whether this is
3075 available is determined at configure time.
3077 New GDB commands can now be written in Python.
3079 * Ada tasking support
3081 Ada tasks can now be inspected in GDB. The following commands have
3085 Print the list of Ada tasks.
3087 Print detailed information about task number N.
3089 Print the task number of the current task.
3091 Switch the context of debugging to task number N.
3093 * Support for user-defined prefixed commands. The "define" command can
3094 add new commands to existing prefixes, e.g. "target".
3096 * Multi-inferior, multi-process debugging.
3098 GDB now has generalized support for multi-inferior debugging. See
3099 "Debugging Multiple Inferiors" in the manual for more information.
3100 Although availability still depends on target support, the command
3101 set is more uniform now. The GNU/Linux specific multi-forks support
3102 has been migrated to this new framework. This implied some user
3103 visible changes; see "New commands" and also "Removed commands"
3106 * Target descriptions can now describe the target OS ABI. See the
3107 "Target Description Format" section in the user manual for more
3110 * Target descriptions can now describe "compatible" architectures
3111 to indicate that the target can execute applications for a different
3112 architecture in addition to those for the main target architecture.
3113 See the "Target Description Format" section in the user manual for
3116 * Multi-architecture debugging.
3118 GDB now includes general supports for debugging applications on
3119 hybrid systems that use more than one single processor architecture
3120 at the same time. Each such hybrid architecture still requires
3121 specific support to be added. The only hybrid architecture supported
3122 in this version of GDB is the Cell Broadband Engine.
3124 * GDB now supports integrated debugging of Cell/B.E. applications that
3125 use both the PPU and SPU architectures. To enable support for hybrid
3126 Cell/B.E. debugging, you need to configure GDB to support both the
3127 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3128 --enable-targets configure option.
3130 * Non-stop mode debugging.
3132 For some targets, GDB now supports an optional mode of operation in
3133 which you can examine stopped threads while other threads continue
3134 to execute freely. This is referred to as non-stop mode, with the
3135 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3136 section in the user manual for more information.
3138 To be able to support remote non-stop debugging, a remote stub needs
3139 to implement the non-stop mode remote protocol extensions, as
3140 described in the "Remote Non-Stop" section of the user manual. The
3141 GDB remote stub, gdbserver, has been adjusted to support these
3142 extensions on linux targets.
3144 * New commands (for set/show, see "New options" below)
3146 catch syscall [NAME(S) | NUMBER(S)]
3147 Catch system calls. Arguments, which should be names of system
3148 calls or their numbers, mean catch only those syscalls. Without
3149 arguments, every syscall will be caught. When the inferior issues
3150 any of the specified syscalls, GDB will stop and announce the system
3151 call, both when it is called and when its call returns. This
3152 feature is currently available with a native GDB running on the
3153 Linux Kernel, under the following architectures: x86, x86_64,
3154 PowerPC and PowerPC64.
3156 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3158 Search memory for a sequence of bytes.
3160 maint set python print-stack
3161 maint show python print-stack
3162 Show a stack trace when an error is encountered in a Python script.
3165 Invoke CODE by passing it to the Python interpreter.
3170 These allow macros to be defined, undefined, and listed
3174 Show operating system information about processes.
3177 List the inferiors currently under GDB's control.
3180 Switch focus to inferior number NUM.
3183 Detach from inferior number NUM.
3186 Kill inferior number NUM.
3190 set spu stop-on-load
3191 show spu stop-on-load
3192 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3194 set spu auto-flush-cache
3195 show spu auto-flush-cache
3196 Control whether to automatically flush the software-managed cache
3197 during Cell/B.E. debugging.
3199 set sh calling-convention
3200 show sh calling-convention
3201 Control the calling convention used when calling SH target functions.
3204 show debug timestamp
3205 Control display of timestamps with GDB debugging output.
3207 set disassemble-next-line
3208 show disassemble-next-line
3209 Control display of disassembled source lines or instructions when
3212 set remote noack-packet
3213 show remote noack-packet
3214 Set/show the use of remote protocol QStartNoAckMode packet. See above
3215 under "New remote packets."
3217 set remote query-attached-packet
3218 show remote query-attached-packet
3219 Control use of remote protocol `qAttached' (query-attached) packet.
3221 set remote read-siginfo-object
3222 show remote read-siginfo-object
3223 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3226 set remote write-siginfo-object
3227 show remote write-siginfo-object
3228 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3231 set remote reverse-continue
3232 show remote reverse-continue
3233 Control use of remote protocol 'bc' (reverse-continue) packet.
3235 set remote reverse-step
3236 show remote reverse-step
3237 Control use of remote protocol 'bs' (reverse-step) packet.
3239 set displaced-stepping
3240 show displaced-stepping
3241 Control displaced stepping mode. Displaced stepping is a way to
3242 single-step over breakpoints without removing them from the debuggee.
3243 Also known as "out-of-line single-stepping".
3246 show debug displaced
3247 Control display of debugging info for displaced stepping.
3249 maint set internal-error
3250 maint show internal-error
3251 Control what GDB does when an internal error is detected.
3253 maint set internal-warning
3254 maint show internal-warning
3255 Control what GDB does when an internal warning is detected.
3260 Use a wrapper program to launch programs for debugging.
3262 set multiple-symbols (all|ask|cancel)
3263 show multiple-symbols
3264 The value of this variable can be changed to adjust the debugger behavior
3265 when an expression or a breakpoint location contains an ambiguous symbol
3266 name (an overloaded function name, for instance).
3268 set breakpoint always-inserted
3269 show breakpoint always-inserted
3270 Keep breakpoints always inserted in the target, as opposed to inserting
3271 them when resuming the target, and removing them when the target stops.
3272 This option can improve debugger performance on slow remote targets.
3274 set arm fallback-mode (arm|thumb|auto)
3275 show arm fallback-mode
3276 set arm force-mode (arm|thumb|auto)
3278 These commands control how ARM GDB determines whether instructions
3279 are ARM or Thumb. The default for both settings is auto, which uses
3280 the current CPSR value for instructions without symbols; previous
3281 versions of GDB behaved as if "set arm fallback-mode arm".
3283 set disable-randomization
3284 show disable-randomization
3285 Standalone programs run with the virtual address space randomization enabled
3286 by default on some platforms. This option keeps the addresses stable across
3287 multiple debugging sessions.
3291 Control whether other threads are stopped or not when some thread hits
3296 Requests that asynchronous execution is enabled in the target, if available.
3297 In this case, it's possible to resume target in the background, and interact
3298 with GDB while the target is running. "show target-async" displays the
3299 current state of asynchronous execution of the target.
3301 set target-wide-charset
3302 show target-wide-charset
3303 The target-wide-charset is the name of the character set that GDB
3304 uses when printing characters whose type is wchar_t.
3306 set tcp auto-retry (on|off)
3308 set tcp connect-timeout
3309 show tcp connect-timeout
3310 These commands allow GDB to retry failed TCP connections to a remote stub
3311 with a specified timeout period; this is useful if the stub is launched
3312 in parallel with GDB but may not be ready to accept connections immediately.
3314 set libthread-db-search-path
3315 show libthread-db-search-path
3316 Control list of directories which GDB will search for appropriate
3319 set schedule-multiple (on|off)
3320 show schedule-multiple
3321 Allow GDB to resume all threads of all processes or only threads of
3322 the current process.
3326 Use more aggressive caching for accesses to the stack. This improves
3327 performance of remote debugging (particularly backtraces) without
3328 affecting correctness.
3330 set interactive-mode (on|off|auto)
3331 show interactive-mode
3332 Control whether GDB runs in interactive mode (on) or not (off).
3333 When in interactive mode, GDB waits for the user to answer all
3334 queries. Otherwise, GDB does not wait and assumes the default
3335 answer. When set to auto (the default), GDB determines which
3336 mode to use based on the stdin settings.
3341 For program forks, this is replaced by the new more generic `info
3342 inferiors' command. To list checkpoints, you can still use the
3343 `info checkpoints' command, which was an alias for the `info forks'
3347 Replaced by the new `inferior' command. To switch between
3348 checkpoints, you can still use the `restart' command, which was an
3349 alias for the `fork' command.
3352 This is removed, since some targets don't have a notion of
3353 processes. To switch between processes, you can still use the
3354 `inferior' command using GDB's own inferior number.
3357 For program forks, this is replaced by the new more generic `kill
3358 inferior' command. To delete a checkpoint, you can still use the
3359 `delete checkpoint' command, which was an alias for the `delete
3363 For program forks, this is replaced by the new more generic `detach
3364 inferior' command. To detach a checkpoint, you can still use the
3365 `detach checkpoint' command, which was an alias for the `detach
3368 * New native configurations
3370 x86/x86_64 Darwin i[34567]86-*-darwin*
3372 x86_64 MinGW x86_64-*-mingw*
3376 Lattice Mico32 lm32-*
3377 x86 DICOS i[34567]86-*-dicos*
3378 x86_64 DICOS x86_64-*-dicos*
3381 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3382 (mingw32ce) debugging.
3388 These commands were actually not implemented on any target.
3390 *** Changes in GDB 6.8
3392 * New native configurations
3394 NetBSD/hppa hppa*-*netbsd*
3395 Xtensa GNU/Linux xtensa*-*-linux*
3399 NetBSD/hppa hppa*-*-netbsd*
3400 Xtensa GNU/Lunux xtensa*-*-linux*
3402 * Change in command line behavior -- corefiles vs. process ids.
3404 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3405 attaching to process NUMBER fails, GDB no longer attempts to open a
3406 core file named NUMBER. Attaching to a program using the -c option
3407 is no longer supported. Instead, use the '-p' or '--pid' options.
3409 * GDB can now be built as a native debugger for debugging Windows x86
3410 (mingw32) Portable Executable (PE) programs.
3412 * Pending breakpoints no longer change their number when their address
3415 * GDB now supports breakpoints with multiple locations,
3416 including breakpoints on C++ constructors, inside C++ templates,
3417 and in inlined functions.
3419 * GDB's ability to debug optimized code has been improved. GDB more
3420 accurately identifies function bodies and lexical blocks that occupy
3421 more than one contiguous range of addresses.
3423 * Target descriptions can now describe registers for PowerPC.
3425 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3426 registers on PowerPC targets.
3428 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3429 targets even when the libthread_db library is not available.
3431 * The GDB remote stub, gdbserver, now supports the new file transfer
3432 commands (remote put, remote get, and remote delete).
3434 * The GDB remote stub, gdbserver, now supports run and attach in
3435 extended-remote mode.
3437 * hppa*64*-*-hpux11* target broken
3438 The debugger is unable to start a program and fails with the following
3439 error: "Error trying to get information about dynamic linker".
3440 The gdb-6.7 release is also affected.
3442 * GDB now supports the --enable-targets= configure option to allow
3443 building a single GDB executable that supports multiple remote
3444 target architectures.
3446 * GDB now supports debugging C and C++ programs which use the
3447 Decimal Floating Point extension. In addition, the PowerPC target
3448 now has a set of pseudo-registers to inspect decimal float values
3449 stored in two consecutive float registers.
3451 * The -break-insert MI command can optionally create pending
3454 * Improved support for debugging Ada
3455 Many improvements to the Ada language support have been made. These
3457 - Better support for Ada2005 interface types
3458 - Improved handling of arrays and slices in general
3459 - Better support for Taft-amendment types
3460 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3462 - Improved command completion in Ada
3465 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3470 set print frame-arguments (all|scalars|none)
3471 show print frame-arguments
3472 The value of this variable can be changed to control which argument
3473 values should be printed by the debugger when displaying a frame.
3478 Transfer files to and from a remote target, and delete remote files.
3485 Transfer files to and from a remote target, and delete remote files.
3487 * New remote packets
3494 Open, close, read, write, and delete files on the remote system.
3497 Attach to an existing process on the remote system, in extended-remote
3501 Run a new process on the remote system, in extended-remote mode.
3503 *** Changes in GDB 6.7
3505 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3506 bfd, libiberty and opcodes, as revealed by static analysis donated by
3507 Coverity, Inc. (http://scan.coverity.com).
3509 * When looking up multiply-defined global symbols, GDB will now prefer the
3510 symbol definition in the current shared library if it was built using the
3511 -Bsymbolic linker option.
3513 * When the Text User Interface (TUI) is not configured, GDB will now
3514 recognize the -tui command-line option and print a message that the TUI
3517 * The GDB remote stub, gdbserver, now has lower overhead for high
3518 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3520 * GDB for MIPS targets now autodetects whether a remote target provides
3521 32-bit or 64-bit register values.
3523 * Support for C++ member pointers has been improved.
3525 * GDB now understands XML target descriptions, which specify the
3526 target's overall architecture. GDB can read a description from
3527 a local file or over the remote serial protocol.
3529 * Vectors of single-byte data use a new integer type which is not
3530 automatically displayed as character or string data.
3532 * The /s format now works with the print command. It displays
3533 arrays of single-byte integers and pointers to single-byte integers
3536 * Target descriptions can now describe target-specific registers,
3537 for architectures which have implemented the support (currently
3538 only ARM, M68K, and MIPS).
3540 * GDB and the GDB remote stub, gdbserver, now support the XScale
3543 * The GDB remote stub, gdbserver, has been updated to support
3544 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3545 has been rewritten to use the standard GDB remote protocol.
3547 * GDB can now step into C++ functions which are called through thunks.
3549 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3551 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3552 layout. It also supports a TextSeg= and DataSeg= response when only
3553 segment base addresses (rather than offsets) are available.
3555 * The /i format now outputs any trailing branch delay slot instructions
3556 immediately following the last instruction within the count specified.
3558 * The GDB remote protocol "T" stop reply packet now supports a
3559 "library" response. Combined with the new "qXfer:libraries:read"
3560 packet, this response allows GDB to debug shared libraries on targets
3561 where the operating system manages the list of loaded libraries (e.g.
3562 Windows and SymbianOS).
3564 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3565 (DLLs) on Windows and Windows CE targets.
3567 * GDB now supports a faster verification that a .debug file matches its binary
3568 according to its build-id signature, if the signature is present.
3574 Enable or disable hardware flow control (RTS/CTS) on the serial port
3575 when debugging using remote targets.
3577 set mem inaccessible-by-default
3578 show mem inaccessible-by-default
3579 If the target supplies a memory map, for instance via the remote
3580 protocol's "qXfer:memory-map:read" packet, setting this variable
3581 prevents GDB from accessing memory outside the memory map. This
3582 is useful for targets with memory mapped registers or which react
3583 badly to accesses of unmapped address space.
3585 set breakpoint auto-hw
3586 show breakpoint auto-hw
3587 If the target supplies a memory map, for instance via the remote
3588 protocol's "qXfer:memory-map:read" packet, setting this variable
3589 lets GDB use hardware breakpoints automatically for memory regions
3590 where it can not use software breakpoints. This covers both the
3591 "break" command and internal breakpoints used for other commands
3592 including "next" and "finish".
3595 catch exception unhandled
3596 Stop the program execution when Ada exceptions are raised.
3599 Stop the program execution when an Ada assertion failed.
3603 Set an alternate system root for target files. This is a more
3604 general version of "set solib-absolute-prefix", which is now
3605 an alias to "set sysroot".
3608 Provide extended SPU facility status information. This set of
3609 commands is available only when debugging the Cell/B.E. SPU
3612 * New native configurations
3614 OpenBSD/sh sh*-*openbsd*
3617 unset tdesc filename
3619 Use the specified local file as an XML target description, and do
3620 not query the target for its built-in description.
3624 OpenBSD/sh sh*-*-openbsd*
3625 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3626 Toshiba Media Processor mep-elf
3628 * New remote packets
3631 Ignore the specified signals; pass them directly to the debugged program
3632 without stopping other threads or reporting them to GDB.
3634 qXfer:features:read:
3635 Read an XML target description from the target, which describes its
3640 Read or write contents of an spufs file on the target system. These
3641 packets are available only on the Cell/B.E. SPU architecture.
3643 qXfer:libraries:read:
3644 Report the loaded shared libraries. Combined with new "T" packet
3645 response, this packet allows GDB to debug shared libraries on
3646 targets where the operating system manages the list of loaded
3647 libraries (e.g. Windows and SymbianOS).
3651 Support for these obsolete configurations has been removed.
3659 i[34567]86-*-lynxos*
3660 i[34567]86-*-netware*
3661 i[34567]86-*-sco3.2v5*
3662 i[34567]86-*-sco3.2v4*
3664 i[34567]86-*-sysv4.2*
3667 i[34567]86-*-unixware2*
3668 i[34567]86-*-unixware*
3677 * Other removed features
3684 Various m68k-only ROM monitors.
3691 Various Renesas ROM monitors and debugging interfaces for SH and
3696 Support for a Macraigor serial interface to on-chip debugging.
3697 GDB does not directly support the newer parallel or USB
3702 A debug information format. The predecessor to DWARF 2 and
3703 DWARF 3, which are still supported.
3705 Support for the HP aCC compiler on HP-UX/PA-RISC
3707 SOM-encapsulated symbolic debugging information, automatic
3708 invocation of pxdb, and the aCC custom C++ ABI. This does not
3709 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3710 with aCC can still be debugged on an assembly level.
3712 MIPS ".pdr" sections
3714 A MIPS-specific format used to describe stack frame layout
3715 in debugging information.
3719 GDB could work with an older version of Guile to debug
3720 the interpreter and Scheme programs running in it.
3722 set mips stack-arg-size
3723 set mips saved-gpreg-size
3725 Use "set mips abi" to control parameter passing for MIPS.
3727 *** Changes in GDB 6.6
3732 Cell Broadband Engine SPU spu-elf
3734 * GDB can now be configured as a cross-debugger targeting native Windows
3735 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3736 running on a Windows system over TCP/IP to debug Windows programs.
3738 * The GDB remote stub, gdbserver, has been updated to support Windows and
3739 Cygwin debugging. Both single-threaded and multi-threaded programs are
3742 * The "set trust-readonly-sections" command works again. This command was
3743 broken in GDB 6.3, 6.4, and 6.5.
3745 * The "load" command now supports writing to flash memory, if the remote
3746 stub provides the required support.
3748 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3749 longer requires symbolic debug information (e.g. DWARF-2).
3754 unset substitute-path
3755 show substitute-path
3756 Manage a list of substitution rules that GDB uses to rewrite the name
3757 of the directories where the sources are located. This can be useful
3758 for instance when the sources were moved to a different location
3759 between compilation and debugging.
3763 Print each CLI command as it is executed. Each command is prefixed with
3764 a number of `+' symbols representing the nesting depth.
3765 The source command now has a `-v' option to enable the same feature.
3769 The ARM Demon monitor support (RDP protocol, "target rdp").
3771 Kernel Object Display, an embedded debugging feature which only worked with
3772 an obsolete version of Cisco IOS.
3774 The 'set download-write-size' and 'show download-write-size' commands.
3776 * New remote packets
3779 Tell a stub about GDB client features, and request remote target features.
3780 The first feature implemented is PacketSize, which allows the target to
3781 specify the size of packets it can handle - to minimize the number of
3782 packets required and improve performance when connected to a remote
3786 Fetch an OS auxilliary vector from the remote stub. This packet is a
3787 more efficient replacement for qPart:auxv:read.
3789 qXfer:memory-map:read:
3790 Fetch a memory map from the remote stub, including information about
3791 RAM, ROM, and flash memory devices.
3796 Erase and program a flash memory device.
3798 * Removed remote packets
3801 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3802 used it, and only gdbserver implemented it.
3804 *** Changes in GDB 6.5
3808 Renesas M32C/M16C m32c-elf
3810 Morpho Technologies ms1 ms1-elf
3814 init-if-undefined Initialize a convenience variable, but
3815 only if it doesn't already have a value.
3817 The following commands are presently only implemented for native GNU/Linux:
3819 checkpoint Save a snapshot of the program state.
3821 restart <n> Return the program state to a
3822 previously saved state.
3824 info checkpoints List currently saved checkpoints.
3826 delete-checkpoint <n> Delete a previously saved checkpoint.
3828 set|show detach-on-fork Tell gdb whether to detach from a newly
3829 forked process, or to keep debugging it.
3831 info forks List forks of the user program that
3832 are available to be debugged.
3834 fork <n> Switch to debugging one of several
3835 forks of the user program that are
3836 available to be debugged.
3838 delete-fork <n> Delete a fork from the list of forks
3839 that are available to be debugged (and
3840 kill the forked process).
3842 detach-fork <n> Delete a fork from the list of forks
3843 that are available to be debugged (and
3844 allow the process to continue).
3848 Morpho Technologies ms2 ms1-elf
3850 * Improved Windows host support
3852 GDB now builds as a cross debugger hosted on i686-mingw32, including
3853 native console support, and remote communications using either
3854 network sockets or serial ports.
3856 * Improved Modula-2 language support
3858 GDB can now print most types in the Modula-2 syntax. This includes:
3859 basic types, set types, record types, enumerated types, range types,
3860 pointer types and ARRAY types. Procedure var parameters are correctly
3861 printed and hexadecimal addresses and character constants are also
3862 written in the Modula-2 syntax. Best results can be obtained by using
3863 GNU Modula-2 together with the -gdwarf-2 command line option.
3867 The ARM rdi-share module.
3869 The Netware NLM debug server.
3871 *** Changes in GDB 6.4
3873 * New native configurations
3875 OpenBSD/arm arm*-*-openbsd*
3876 OpenBSD/mips64 mips64-*-openbsd*
3880 Morpho Technologies ms1 ms1-elf
3882 * New command line options
3884 --batch-silent As for --batch, but totally silent.
3885 --return-child-result The debugger will exist with the same value
3886 the child (debugged) program exited with.
3887 --eval-command COMMAND, -ex COMMAND
3888 Execute a single GDB CLI command. This may be
3889 specified multiple times and in conjunction
3890 with the --command (-x) option.
3892 * Deprecated commands removed
3894 The following commands, that were deprecated in 2000, have been
3898 set|show arm disassembly-flavor set|show arm disassembler
3899 othernames set arm disassembler
3900 set|show remotedebug set|show debug remote
3901 set|show archdebug set|show debug arch
3902 set|show eventdebug set|show debug event
3905 * New BSD user-level threads support
3907 It is now possible to debug programs using the user-level threads
3908 library on OpenBSD and FreeBSD. Currently supported (target)
3911 FreeBSD/amd64 x86_64-*-freebsd*
3912 FreeBSD/i386 i386-*-freebsd*
3913 OpenBSD/i386 i386-*-openbsd*
3915 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3916 are not yet supported.
3918 * New support for Matsushita MN10300 w/sim added
3919 (Work in progress). mn10300-elf.
3921 * REMOVED configurations and files
3923 VxWorks and the XDR protocol *-*-vxworks
3924 Motorola MCORE mcore-*-*
3925 National Semiconductor NS32000 ns32k-*-*
3927 * New "set print array-indexes" command
3929 After turning this setting "on", GDB prints the index of each element
3930 when displaying arrays. The default is "off" to preserve the previous
3933 * VAX floating point support
3935 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3937 * User-defined command support
3939 In addition to using $arg0..$arg9 for argument passing, it is now possible
3940 to use $argc to determine now many arguments have been passed. See the
3941 section on user-defined commands in the user manual for more information.
3943 *** Changes in GDB 6.3:
3945 * New command line option
3947 GDB now accepts -l followed by a number to set the timeout for remote
3950 * GDB works with GCC -feliminate-dwarf2-dups
3952 GDB now supports a more compact representation of DWARF-2 debug
3953 information using DW_FORM_ref_addr references. These are produced
3954 by GCC with the option -feliminate-dwarf2-dups and also by some
3955 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3956 to use -feliminate-dwarf2-dups.
3958 * Internationalization
3960 When supported by the host system, GDB will be built with
3961 internationalization (libintl). The task of marking up the sources is
3962 continued, we're looking forward to our first translation.
3966 Initial support for debugging programs compiled with the GNAT
3967 implementation of the Ada programming language has been integrated
3968 into GDB. In this release, support is limited to expression evaluation.
3970 * New native configurations
3972 GNU/Linux/m32r m32r-*-linux-gnu
3976 GDB's remote protocol now includes support for the 'p' packet. This
3977 packet is used to fetch individual registers from a remote inferior.
3979 * END-OF-LIFE registers[] compatibility module
3981 GDB's internal register infrastructure has been completely rewritten.
3982 The new infrastructure making possible the implementation of key new
3983 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3986 GDB 6.3 will be the last release to include the the registers[]
3987 compatibility module that allowed out-of-date configurations to
3988 continue to work. This change directly impacts the following
3998 powerpc bdm protocol
4000 Unless there is activity to revive these configurations, they will be
4001 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4003 * OBSOLETE configurations and files
4005 Configurations that have been declared obsolete in this release have
4006 been commented out. Unless there is activity to revive these
4007 configurations, the next release of GDB will have their sources
4008 permanently REMOVED.
4017 *** Changes in GDB 6.2.1:
4019 * MIPS `break main; run' gave an heuristic-fence-post warning
4021 When attempting to run even a simple program, a warning about
4022 heuristic-fence-post being hit would be reported. This problem has
4025 * MIPS IRIX 'long double' crashed GDB
4027 When examining a long double variable, GDB would get a segmentation
4028 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4029 IRIX long double values).
4033 A bug in the VAX stack code was causing problems with the "next"
4034 command. This problem has been fixed.
4036 *** Changes in GDB 6.2:
4038 * Fix for ``many threads''
4040 On GNU/Linux systems that use the NPTL threads library, a program
4041 rapidly creating and deleting threads would confuse GDB leading to the
4044 ptrace: No such process.
4045 thread_db_get_info: cannot get thread info: generic error
4047 This problem has been fixed.
4049 * "-async" and "-noasync" options removed.
4051 Support for the broken "-noasync" option has been removed (it caused
4054 * New ``start'' command.
4056 This command runs the program until the begining of the main procedure.
4058 * New BSD Kernel Data Access Library (libkvm) interface
4060 Using ``target kvm'' it is now possible to debug kernel core dumps and
4061 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4062 platforms. Currently supported (native-only) configurations are:
4064 FreeBSD/amd64 x86_64-*-freebsd*
4065 FreeBSD/i386 i?86-*-freebsd*
4066 NetBSD/i386 i?86-*-netbsd*
4067 NetBSD/m68k m68*-*-netbsd*
4068 NetBSD/sparc sparc-*-netbsd*
4069 OpenBSD/amd64 x86_64-*-openbsd*
4070 OpenBSD/i386 i?86-*-openbsd*
4071 OpenBSD/m68k m68*-openbsd*
4072 OpenBSD/sparc sparc-*-openbsd*
4074 * Signal trampoline code overhauled
4076 Many generic problems with GDB's signal handling code have been fixed.
4077 These include: backtraces through non-contiguous stacks; recognition
4078 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4079 call; backtrace through a signal trampoline; step into and out of
4080 signal handlers; and single-stepping in the signal trampoline.
4082 Please note that kernel bugs are a limiting factor here. These
4083 features have been shown to work on an s390 GNU/Linux system that
4084 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4086 * Cygwin support for DWARF 2 added.
4088 * New native configurations
4090 GNU/Linux/hppa hppa*-*-linux*
4091 OpenBSD/hppa hppa*-*-openbsd*
4092 OpenBSD/m68k m68*-*-openbsd*
4093 OpenBSD/m88k m88*-*-openbsd*
4094 OpenBSD/powerpc powerpc-*-openbsd*
4095 NetBSD/vax vax-*-netbsd*
4096 OpenBSD/vax vax-*-openbsd*
4098 * END-OF-LIFE frame compatibility module
4100 GDB's internal frame infrastructure has been completely rewritten.
4101 The new infrastructure making it possible to support key new features
4102 including DWARF 2 Call Frame Information. To aid in the task of
4103 migrating old configurations to this new infrastructure, a
4104 compatibility module, that allowed old configurations to continue to
4105 work, was also included.
4107 GDB 6.2 will be the last release to include this frame compatibility
4108 module. This change directly impacts the following configurations:
4118 Unless there is activity to revive these configurations, they will be
4119 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4121 * REMOVED configurations and files
4123 Sun 3, running SunOS 3 m68*-*-sunos3*
4124 Sun 3, running SunOS 4 m68*-*-sunos4*
4125 Sun 2, running SunOS 3 m68000-*-sunos3*
4126 Sun 2, running SunOS 4 m68000-*-sunos4*
4127 Motorola 680x0 running LynxOS m68*-*-lynxos*
4128 AT&T 3b1/Unix pc m68*-att-*
4129 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4130 decstation mips-dec-* mips-little-*
4131 riscos mips-*-riscos* mips-*-sysv*
4132 sonymips mips-sony-*
4133 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4135 *** Changes in GDB 6.1.1:
4137 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4139 The TUI (Text-mode User Interface) is now built as part of a default
4140 GDB configuration. It is enabled by either selecting the TUI with the
4141 command line option "-i=tui" or by running the separate "gdbtui"
4142 program. For more information on the TUI, see the manual "Debugging
4145 * Pending breakpoint support (also included in GDB 6.1)
4147 Support has been added to allow you to specify breakpoints in shared
4148 libraries that have not yet been loaded. If a breakpoint location
4149 cannot be found, and the "breakpoint pending" option is set to auto,
4150 GDB queries you if you wish to make the breakpoint pending on a future
4151 shared-library load. If and when GDB resolves the breakpoint symbol,
4152 the pending breakpoint is removed as one or more regular breakpoints
4155 Pending breakpoints are very useful for GCJ Java debugging.
4157 * Fixed ISO-C build problems
4159 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4160 non ISO-C code that stopped them being built using a more strict ISO-C
4161 compiler (e.g., IBM's C compiler).
4163 * Fixed build problem on IRIX 5
4165 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4166 wasn't able to compile compile on an IRIX 5 system.
4168 * Added execute permission to gdb/gdbserver/configure
4170 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4171 permission. This bug would cause configure to fail on a number of
4172 systems (Solaris, IRIX). Ref: server/519.
4174 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4176 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4177 has been updated to use constant array sizes.
4179 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4181 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4182 its generated DWARF Call Frame Info. This encoding was causing GDB to
4183 panic, that panic has been fixed. Ref: gdb/1628.
4185 * Fixed a problem when examining parameters in shared library code.
4187 When examining parameters in optimized shared library code generated
4188 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4189 not available''. GDB now correctly displays the variable's value.
4191 *** Changes in GDB 6.1:
4193 * Removed --with-mmalloc
4195 Support for the mmalloc memory manager has been removed, as it
4196 conflicted with the internal gdb byte cache.
4198 * Changes in AMD64 configurations
4200 The AMD64 target now includes the %cs and %ss registers. As a result
4201 the AMD64 remote protocol has changed; this affects the floating-point
4202 and SSE registers. If you rely on those registers for your debugging,
4203 you should upgrade gdbserver on the remote side.
4205 * Revised SPARC target
4207 The SPARC target has been completely revised, incorporating the
4208 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4209 support for LynxOS and SunOS 4 has been dropped. Calling functions
4210 from within GDB on operating systems with a non-executable stack
4211 (Solaris, OpenBSD) now works.
4215 GDB has a new C++ demangler which does a better job on the mangled
4216 names generated by current versions of g++. It also runs faster, so
4217 with this and other changes gdb should now start faster on large C++
4220 * DWARF 2 Location Expressions
4222 GDB support for location expressions has been extended to support function
4223 arguments and frame bases. Older versions of GDB could crash when they
4226 * C++ nested types and namespaces
4228 GDB's support for nested types and namespaces in C++ has been
4229 improved, especially if you use the DWARF 2 debugging format. (This
4230 is the default for recent versions of GCC on most platforms.)
4231 Specifically, if you have a class "Inner" defined within a class or
4232 namespace "Outer", then GDB realizes that the class's name is
4233 "Outer::Inner", not simply "Inner". This should greatly reduce the
4234 frequency of complaints about not finding RTTI symbols. In addition,
4235 if you are stopped at inside of a function defined within a namespace,
4236 GDB modifies its name lookup accordingly.
4238 * New native configurations
4240 NetBSD/amd64 x86_64-*-netbsd*
4241 OpenBSD/amd64 x86_64-*-openbsd*
4242 OpenBSD/alpha alpha*-*-openbsd*
4243 OpenBSD/sparc sparc-*-openbsd*
4244 OpenBSD/sparc64 sparc64-*-openbsd*
4246 * New debugging protocols
4248 M32R with SDI protocol m32r-*-elf*
4250 * "set prompt-escape-char" command deleted.
4252 The command "set prompt-escape-char" has been deleted. This command,
4253 and its very obscure effet on GDB's prompt, was never documented,
4254 tested, nor mentioned in the NEWS file.
4256 * OBSOLETE configurations and files
4258 Configurations that have been declared obsolete in this release have
4259 been commented out. Unless there is activity to revive these
4260 configurations, the next release of GDB will have their sources
4261 permanently REMOVED.
4263 Sun 3, running SunOS 3 m68*-*-sunos3*
4264 Sun 3, running SunOS 4 m68*-*-sunos4*
4265 Sun 2, running SunOS 3 m68000-*-sunos3*
4266 Sun 2, running SunOS 4 m68000-*-sunos4*
4267 Motorola 680x0 running LynxOS m68*-*-lynxos*
4268 AT&T 3b1/Unix pc m68*-att-*
4269 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4270 decstation mips-dec-* mips-little-*
4271 riscos mips-*-riscos* mips-*-sysv*
4272 sonymips mips-sony-*
4273 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4275 * REMOVED configurations and files
4277 SGI Irix-4.x mips-sgi-irix4 or iris4
4278 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4279 Z8000 simulator z8k-zilog-none or z8ksim
4280 Matsushita MN10200 w/simulator mn10200-*-*
4281 H8/500 simulator h8500-hitachi-hms or h8500hms
4282 HP/PA running BSD hppa*-*-bsd*
4283 HP/PA running OSF/1 hppa*-*-osf*
4284 HP/PA Pro target hppa*-*-pro*
4285 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4286 386BSD i[3456]86-*-bsd*
4287 Sequent family i[3456]86-sequent-sysv4*
4288 i[3456]86-sequent-sysv*
4289 i[3456]86-sequent-bsd*
4290 SPARC running LynxOS sparc-*-lynxos*
4291 SPARC running SunOS 4 sparc-*-sunos4*
4292 Tsqware Sparclet sparclet-*-*
4293 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4295 *** Changes in GDB 6.0:
4299 Support for debugging the Objective-C programming language has been
4300 integrated into GDB.
4302 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4304 DWARF 2's Call Frame Information makes available compiler generated
4305 information that more exactly describes the program's run-time stack.
4306 By using this information, GDB is able to provide more robust stack
4309 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4310 have been updated to use a new backtrace mechanism which includes
4311 DWARF 2 CFI support.
4315 GDB's remote protocol has been extended to include support for hosted
4316 file I/O (where the remote target uses GDB's file system). See GDB's
4317 remote protocol documentation for details.
4319 * All targets using the new architecture framework.
4321 All of GDB's targets have been updated to use the new internal
4322 architecture framework. The way is now open for future GDB releases
4323 to include cross-architecture native debugging support (i386 on amd64,
4326 * GNU/Linux's Thread Local Storage (TLS)
4328 GDB now includes support for for the GNU/Linux implementation of
4329 per-thread variables.
4331 * GNU/Linux's Native POSIX Thread Library (NPTL)
4333 GDB's thread code has been updated to work with either the new
4334 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4336 * Separate debug info.
4338 GDB, in conjunction with BINUTILS, now supports a mechanism for
4339 automatically loading debug information from a separate file. Instead
4340 of shipping full debug and non-debug versions of system libraries,
4341 system integrators can now instead ship just the stripped libraries
4342 and optional debug files.
4344 * DWARF 2 Location Expressions
4346 DWARF 2 Location Expressions allow the compiler to more completely
4347 describe the location of variables (even in optimized code) to the
4350 GDB now includes preliminary support for location expressions (support
4351 for DW_OP_piece is still missing).
4355 A number of long standing bugs that caused GDB to die while starting a
4356 Java application have been fixed. GDB's Java support is now
4357 considered "useable".
4359 * GNU/Linux support for fork, vfork, and exec.
4361 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4362 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4365 * GDB supports logging output to a file
4367 There are two new commands, "set logging" and "show logging", which can be
4368 used to capture GDB's output to a file.
4370 * The meaning of "detach" has changed for gdbserver
4372 The "detach" command will now resume the application, as documented. To
4373 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4376 * d10v, m68hc11 `regs' command deprecated
4378 The `info registers' command has been updated so that it displays the
4379 registers using a format identical to the old `regs' command.
4383 A new command, "maint set profile on/off", has been added. This command can
4384 be used to enable or disable profiling while running GDB, to profile a
4385 session or a set of commands. In addition there is a new configure switch,
4386 "--enable-profiling", which will cause GDB to be compiled with profiling
4387 data, for more informative profiling results.
4389 * Default MI syntax changed to "mi2".
4391 The default MI (machine interface) syntax, enabled by the command line
4392 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4393 "mi1", can be enabled by specifying the option "-i=mi1".
4395 Support for the original "mi0" syntax (included in GDB 5.0) has been
4398 Fix for gdb/192: removed extraneous space when displaying frame level.
4399 Fix for gdb/672: update changelist is now output in mi list format.
4400 Fix for gdb/702: a -var-assign that updates the value now shows up
4401 in a subsequent -var-update.
4403 * New native configurations.
4405 FreeBSD/amd64 x86_64-*-freebsd*
4407 * Multi-arched targets.
4409 HP/PA HPUX11 hppa*-*-hpux*
4410 Renesas M32R/D w/simulator m32r-*-elf*
4412 * OBSOLETE configurations and files
4414 Configurations that have been declared obsolete in this release have
4415 been commented out. Unless there is activity to revive these
4416 configurations, the next release of GDB will have their sources
4417 permanently REMOVED.
4419 Z8000 simulator z8k-zilog-none or z8ksim
4420 Matsushita MN10200 w/simulator mn10200-*-*
4421 H8/500 simulator h8500-hitachi-hms or h8500hms
4422 HP/PA running BSD hppa*-*-bsd*
4423 HP/PA running OSF/1 hppa*-*-osf*
4424 HP/PA Pro target hppa*-*-pro*
4425 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4426 Sequent family i[3456]86-sequent-sysv4*
4427 i[3456]86-sequent-sysv*
4428 i[3456]86-sequent-bsd*
4429 Tsqware Sparclet sparclet-*-*
4430 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4432 * REMOVED configurations and files
4435 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4436 IBM AIX PS/2 i[3456]86-*-aix
4437 i386 running Mach 3.0 i[3456]86-*-mach3*
4438 i386 running Mach i[3456]86-*-mach*
4439 i386 running OSF/1 i[3456]86-*osf1mk*
4440 HP/Apollo 68k Family m68*-apollo*-sysv*,
4442 m68*-hp-bsd*, m68*-hp-hpux*
4443 Argonaut Risc Chip (ARC) arc-*-*
4444 Mitsubishi D30V d30v-*-*
4445 Fujitsu FR30 fr30-*-elf*
4446 OS/9000 i[34]86-*-os9k
4447 I960 with MON960 i960-*-coff
4449 * MIPS $fp behavior changed
4451 The convenience variable $fp, for the MIPS, now consistently returns
4452 the address of the current frame's base. Previously, depending on the
4453 context, $fp could refer to either $sp or the current frame's base
4454 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4455 The GNU Source-Level Debugger''.
4457 *** Changes in GDB 5.3:
4459 * GNU/Linux shared library multi-threaded performance improved.
4461 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4462 `/proc', in preference to `ptrace' for memory reads. This may result
4463 in an improvement in the start-up time of multi-threaded, shared
4464 library applications when run under GDB. One GDB user writes: ``loads
4465 shared libs like mad''.
4467 * ``gdbserver'' now supports multi-threaded applications on some targets
4469 Support for debugging multi-threaded applications which use
4470 the GNU/Linux LinuxThreads package has been added for
4471 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4472 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4474 * GDB now supports C/C++ preprocessor macros.
4476 GDB now expands preprocessor macro invocations in C/C++ expressions,
4477 and provides various commands for showing macro definitions and how
4480 The new command `macro expand EXPRESSION' expands any macro
4481 invocations in expression, and shows the result.
4483 The new command `show macro MACRO-NAME' shows the definition of the
4484 macro named MACRO-NAME, and where it was defined.
4486 Most compilers don't include information about macros in the debugging
4487 information by default. In GCC 3.1, for example, you need to compile
4488 your program with the options `-gdwarf-2 -g3'. If the macro
4489 information is present in the executable, GDB will read it.
4491 * Multi-arched targets.
4493 DEC Alpha (partial) alpha*-*-*
4494 DEC VAX (partial) vax-*-*
4496 National Semiconductor NS32000 (partial) ns32k-*-*
4497 Motorola 68000 (partial) m68k-*-*
4498 Motorola MCORE mcore-*-*
4502 Fujitsu FRV architecture added by Red Hat frv*-*-*
4505 * New native configurations
4507 Alpha NetBSD alpha*-*-netbsd*
4508 SH NetBSD sh*-*-netbsdelf*
4509 MIPS NetBSD mips*-*-netbsd*
4510 UltraSPARC NetBSD sparc64-*-netbsd*
4512 * OBSOLETE configurations and files
4514 Configurations that have been declared obsolete in this release have
4515 been commented out. Unless there is activity to revive these
4516 configurations, the next release of GDB will have their sources
4517 permanently REMOVED.
4519 Mitsubishi D30V d30v-*-*
4520 OS/9000 i[34]86-*-os9k
4521 IBM AIX PS/2 i[3456]86-*-aix
4522 Fujitsu FR30 fr30-*-elf*
4523 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4524 Argonaut Risc Chip (ARC) arc-*-*
4525 i386 running Mach 3.0 i[3456]86-*-mach3*
4526 i386 running Mach i[3456]86-*-mach*
4527 i386 running OSF/1 i[3456]86-*osf1mk*
4528 HP/Apollo 68k Family m68*-apollo*-sysv*,
4530 m68*-hp-bsd*, m68*-hp-hpux*
4531 I960 with MON960 i960-*-coff
4533 * OBSOLETE languages
4535 CHILL, a Pascal like language used by telecommunications companies.
4537 * REMOVED configurations and files
4539 AMD 29k family via UDI a29k-amd-udi, udi29k
4540 A29K VxWorks a29k-*-vxworks
4541 AMD 29000 embedded, using EBMON a29k-none-none
4542 AMD 29000 embedded with COFF a29k-none-coff
4543 AMD 29000 embedded with a.out a29k-none-aout
4545 testsuite/gdb.hp/gdb.threads-hp/ directory
4547 * New command "set max-user-call-depth <nnn>"
4549 This command allows the user to limit the call depth of user-defined
4550 commands. The default is 1024.
4552 * Changes in FreeBSD/i386 native debugging.
4554 Support for the "generate-core-file" has been added.
4556 * New commands "dump", "append", and "restore".
4558 These commands allow data to be copied from target memory
4559 to a bfd-format or binary file (dump and append), and back
4560 from a file into memory (restore).
4562 * Improved "next/step" support on multi-processor Alpha Tru64.
4564 The previous single-step mechanism could cause unpredictable problems,
4565 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4566 of a software single-step mechanism prevents this.
4568 *** Changes in GDB 5.2.1:
4576 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4577 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4578 Fix, by Joel Brobecker imported from mainline.
4580 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4581 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4582 Fix, by Fred Fish, imported from mainline.
4584 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4585 Surprisingly enough, it works now.
4586 By Michal Ludvig, imported from mainline.
4588 i386 hardware watchpoint support:
4589 avoid misses on second run for some targets.
4590 By Pierre Muller, imported from mainline.
4592 *** Changes in GDB 5.2:
4594 * New command "set trust-readonly-sections on[off]".
4596 This command is a hint that tells gdb that read-only sections
4597 really are read-only (ie. that their contents will not change).
4598 In this mode, gdb will go to the object file rather than the
4599 target to read memory from read-only sections (such as ".text").
4600 This can be a significant performance improvement on some
4601 (notably embedded) targets.
4603 * New command "generate-core-file" (or "gcore").
4605 This new gdb command allows the user to drop a core file of the child
4606 process state at any time. So far it's been implemented only for
4607 GNU/Linux and Solaris, but should be relatively easily ported to other
4608 hosts. Argument is core file name (defaults to core.<pid>).
4610 * New command line option
4612 GDB now accepts --pid or -p followed by a process id.
4614 * Change in command line behavior -- corefiles vs. process ids.
4616 There is a subtle behavior in the way in which GDB handles
4617 command line arguments. The first non-flag argument is always
4618 a program to debug, but the second non-flag argument may either
4619 be a corefile or a process id. Previously, GDB would attempt to
4620 open the second argument as a corefile, and if that failed, would
4621 issue a superfluous error message and then attempt to attach it as
4622 a process. Now, if the second argument begins with a non-digit,
4623 it will be treated as a corefile. If it begins with a digit,
4624 GDB will attempt to attach it as a process, and if no such process
4625 is found, will then attempt to open it as a corefile.
4627 * Changes in ARM configurations.
4629 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4630 configuration is fully multi-arch.
4632 * New native configurations
4634 ARM NetBSD arm*-*-netbsd*
4635 x86 OpenBSD i[3456]86-*-openbsd*
4636 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4637 Sparc64 running FreeBSD sparc64-*-freebsd*
4641 Sanyo XStormy16 xstormy16-elf
4643 * OBSOLETE configurations and files
4645 Configurations that have been declared obsolete in this release have
4646 been commented out. Unless there is activity to revive these
4647 configurations, the next release of GDB will have their sources
4648 permanently REMOVED.
4650 AMD 29k family via UDI a29k-amd-udi, udi29k
4651 A29K VxWorks a29k-*-vxworks
4652 AMD 29000 embedded, using EBMON a29k-none-none
4653 AMD 29000 embedded with COFF a29k-none-coff
4654 AMD 29000 embedded with a.out a29k-none-aout
4656 testsuite/gdb.hp/gdb.threads-hp/ directory
4658 * REMOVED configurations and files
4660 TI TMS320C80 tic80-*-*
4662 PowerPC Solaris powerpcle-*-solaris*
4663 PowerPC Windows NT powerpcle-*-cygwin32
4664 PowerPC Netware powerpc-*-netware*
4665 Harris/CXUX m88k m88*-harris-cxux*
4666 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4667 ns32k-utek-sysv* ns32k-utek-*
4668 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4669 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4670 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4671 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4672 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4674 * Changes to command line processing
4676 The new `--args' feature can be used to specify command-line arguments
4677 for the inferior from gdb's command line.
4679 * Changes to key bindings
4681 There is a new `operate-and-get-next' function bound to `C-o'.
4683 *** Changes in GDB 5.1.1
4685 Fix compile problem on DJGPP.
4687 Fix a problem with floating-point registers on the i386 being
4690 Fix to stop GDB crashing on .debug_str debug info.
4692 Numerous documentation fixes.
4694 Numerous testsuite fixes.
4696 *** Changes in GDB 5.1:
4698 * New native configurations
4700 Alpha FreeBSD alpha*-*-freebsd*
4701 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4702 MIPS GNU/Linux mips*-*-linux*
4703 MIPS SGI Irix 6.x mips*-sgi-irix6*
4704 ia64 AIX ia64-*-aix*
4705 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4709 Motorola 68HC11 and 68HC12 m68hc11-elf
4711 UltraSparc running GNU/Linux sparc64-*-linux*
4713 * OBSOLETE configurations and files
4715 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4716 Harris/CXUX m88k m88*-harris-cxux*
4717 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4718 ns32k-utek-sysv* ns32k-utek-*
4719 TI TMS320C80 tic80-*-*
4721 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4722 PowerPC Solaris powerpcle-*-solaris*
4723 PowerPC Windows NT powerpcle-*-cygwin32
4724 PowerPC Netware powerpc-*-netware*
4725 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4726 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4727 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4728 Apple Macintosh (MPW) host N/A
4730 stuff.c (Program to stuff files into a specially prepared space in kdb)
4731 kdb-start.c (Main loop for the standalone kernel debugger)
4733 Configurations that have been declared obsolete in this release have
4734 been commented out. Unless there is activity to revive these
4735 configurations, the next release of GDB will have their sources
4736 permanently REMOVED.
4738 * REMOVED configurations and files
4740 Altos 3068 m68*-altos-*
4741 Convex c1-*-*, c2-*-*
4743 ARM RISCix arm-*-* (as host)
4747 * GDB has been converted to ISO C.
4749 GDB's source code has been converted to ISO C. In particular, the
4750 sources are fully protoized, and rely on standard headers being
4755 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4757 * The MI enabled by default.
4759 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4760 revised and enabled by default. Packages which use GDB as a debugging
4761 engine behind a UI or another front end are encouraged to switch to
4762 using the GDB/MI interface, instead of the old annotations interface
4763 which is now deprecated.
4765 * Support for debugging Pascal programs.
4767 GDB now includes support for debugging Pascal programs. The following
4768 main features are supported:
4770 - Pascal-specific data types such as sets;
4772 - automatic recognition of Pascal sources based on file-name
4775 - Pascal-style display of data types, variables, and functions;
4777 - a Pascal expression parser.
4779 However, some important features are not yet supported.
4781 - Pascal string operations are not supported at all;
4783 - there are some problems with boolean types;
4785 - Pascal type hexadecimal constants are not supported
4786 because they conflict with the internal variables format;
4788 - support for Pascal objects and classes is not full yet;
4790 - unlike Pascal, GDB is case-sensitive for symbol names.
4792 * Changes in completion.
4794 Commands such as `shell', `run' and `set args', which pass arguments
4795 to inferior programs, now complete on file names, similar to what
4796 users expect at the shell prompt.
4798 Commands which accept locations, such as `disassemble', `print',
4799 `breakpoint', `until', etc. now complete on filenames as well as
4800 program symbols. Thus, if you type "break foob TAB", and the source
4801 files linked into the programs include `foobar.c', that file name will
4802 be one of the candidates for completion. However, file names are not
4803 considered for completion after you typed a colon that delimits a file
4804 name from a name of a function in that file, as in "break foo.c:bar".
4806 `set demangle-style' completes on available demangling styles.
4808 * New platform-independent commands:
4810 It is now possible to define a post-hook for a command as well as a
4811 hook that runs before the command. For more details, see the
4812 documentation of `hookpost' in the GDB manual.
4814 * Changes in GNU/Linux native debugging.
4816 Support for debugging multi-threaded programs has been completely
4817 revised for all platforms except m68k and sparc. You can now debug as
4818 many threads as your system allows you to have.
4820 Attach/detach is supported for multi-threaded programs.
4822 Support for SSE registers was added for x86. This doesn't work for
4823 multi-threaded programs though.
4825 * Changes in MIPS configurations.
4827 Multi-arch support is enabled for all MIPS configurations.
4829 GDB can now be built as native debugger on SGI Irix 6.x systems for
4830 debugging n32 executables. (Debugging 64-bit executables is not yet
4833 * Unified support for hardware watchpoints in all x86 configurations.
4835 Most (if not all) native x86 configurations support hardware-assisted
4836 breakpoints and watchpoints in a unified manner. This support
4837 implements debug register sharing between watchpoints, which allows to
4838 put a virtually infinite number of watchpoints on the same address,
4839 and also supports watching regions up to 16 bytes with several debug
4842 The new maintenance command `maintenance show-debug-regs' toggles
4843 debugging print-outs in functions that insert, remove, and test
4844 watchpoints and hardware breakpoints.
4846 * Changes in the DJGPP native configuration.
4848 New command ``info dos sysinfo'' displays assorted information about
4849 the CPU, OS, memory, and DPMI server.
4851 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4852 display information about segment descriptors stored in GDT, LDT, and
4855 New commands ``info dos pde'' and ``info dos pte'' display entries
4856 from Page Directory and Page Tables (for now works with CWSDPMI only).
4857 New command ``info dos address-pte'' displays the Page Table entry for
4858 a given linear address.
4860 GDB can now pass command lines longer than 126 characters to the
4861 program being debugged (requires an update to the libdbg.a library
4862 which is part of the DJGPP development kit).
4864 DWARF2 debug info is now supported.
4866 It is now possible to `step' and `next' through calls to `longjmp'.
4868 * Changes in documentation.
4870 All GDB documentation was converted to GFDL, the GNU Free
4871 Documentation License.
4873 Tracepoints-related commands are now fully documented in the GDB
4876 TUI, the Text-mode User Interface, is now documented in the manual.
4878 Tracepoints-related commands are now fully documented in the GDB
4881 The "GDB Internals" manual now has an index. It also includes
4882 documentation of `ui_out' functions, GDB coding standards, x86
4883 hardware watchpoints, and memory region attributes.
4885 * GDB's version number moved to ``version.in''
4887 The Makefile variable VERSION has been replaced by the file
4888 ``version.in''. People creating GDB distributions should update the
4889 contents of this file.
4893 GUD support is now a standard part of the EMACS distribution.
4895 *** Changes in GDB 5.0:
4897 * Improved support for debugging FP programs on x86 targets
4899 Unified and much-improved support for debugging floating-point
4900 programs on all x86 targets. In particular, ``info float'' now
4901 displays the FP registers in the same format on all x86 targets, with
4902 greater level of detail.
4904 * Improvements and bugfixes in hardware-assisted watchpoints
4906 It is now possible to watch array elements, struct members, and
4907 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4908 on x86 targets no longer erroneously trigger when the address is
4911 * Improvements in the native DJGPP version of GDB
4913 The distribution now includes all the scripts and auxiliary files
4914 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4915 machines ``out of the box''.
4917 The DJGPP version can now debug programs that use signals. It is
4918 possible to catch signals that happened in the debuggee, deliver
4919 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4920 would kill the program being debugged.) Programs that hook hardware
4921 interrupts (keyboard, timer, etc.) can also be debugged.
4923 It is now possible to debug DJGPP programs that redirect their
4924 standard handles or switch them to raw (as opposed to cooked) mode, or
4925 even close them. The command ``run < foo > bar'' works as expected,
4926 and ``info terminal'' reports useful information about the debuggee's
4927 terminal, including raw/cooked mode, redirection, etc.
4929 The DJGPP version now uses termios functions for console I/O, which
4930 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4933 DOS-style file names with drive letters are now fully supported by
4936 It is now possible to debug DJGPP programs that switch their working
4937 directory. It is also possible to rerun the debuggee any number of
4938 times without restarting GDB; thus, you can use the same setup,
4939 breakpoints, etc. for many debugging sessions.
4941 * New native configurations
4943 ARM GNU/Linux arm*-*-linux*
4944 PowerPC GNU/Linux powerpc-*-linux*
4948 Motorola MCore mcore-*-*
4949 x86 VxWorks i[3456]86-*-vxworks*
4950 PowerPC VxWorks powerpc-*-vxworks*
4951 TI TMS320C80 tic80-*-*
4953 * OBSOLETE configurations
4955 Altos 3068 m68*-altos-*
4956 Convex c1-*-*, c2-*-*
4958 ARM RISCix arm-*-* (as host)
4961 Configurations that have been declared obsolete will be commented out,
4962 but the code will be left in place. If there is no activity to revive
4963 these configurations before the next release of GDB, the sources will
4964 be permanently REMOVED.
4966 * Gould support removed
4968 Support for the Gould PowerNode and NP1 has been removed.
4970 * New features for SVR4
4972 On SVR4 native platforms (such as Solaris), if you attach to a process
4973 without first loading a symbol file, GDB will now attempt to locate and
4974 load symbols from the running process's executable file.
4976 * Many C++ enhancements
4978 C++ support has been greatly improved. Overload resolution now works properly
4979 in almost all cases. RTTI support is on the way.
4981 * Remote targets can connect to a sub-program
4983 A popen(3) style serial-device has been added. This device starts a
4984 sub-process (such as a stand-alone simulator) and then communicates
4985 with that. The sub-program to run is specified using the syntax
4986 ``|<program> <args>'' vis:
4988 (gdb) set remotedebug 1
4989 (gdb) target extended-remote |mn10300-elf-sim program-args
4991 * MIPS 64 remote protocol
4993 A long standing bug in the mips64 remote protocol where by GDB
4994 expected certain 32 bit registers (ex SR) to be transfered as 32
4995 instead of 64 bits has been fixed.
4997 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4998 added to provide backward compatibility with older versions of GDB.
5000 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5002 The command ``set remotebinarydownload'' command has been replaced by
5003 ``set remote X-packet''. Other commands in ``set remote'' family
5004 include ``set remote P-packet''.
5006 * Breakpoint commands accept ranges.
5008 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5009 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5010 ``tracepoint passcount'' also accepts a range of tracepoints.
5012 * ``apropos'' command added.
5014 The ``apropos'' command searches through command names and
5015 documentation strings, printing out matches, making it much easier to
5016 try to find a command that does what you are looking for.
5020 A new machine oriented interface (MI) has been added to GDB. This
5021 interface is designed for debug environments running GDB as a separate
5022 process. This is part of the long term libGDB project. See the
5023 "GDB/MI" chapter of the GDB manual for further information. It can be
5024 enabled by configuring with:
5026 .../configure --enable-gdbmi
5028 *** Changes in GDB-4.18:
5030 * New native configurations
5032 HP-UX 10.20 hppa*-*-hpux10.20
5033 HP-UX 11.x hppa*-*-hpux11.0*
5034 M68K GNU/Linux m68*-*-linux*
5038 Fujitsu FR30 fr30-*-elf*
5039 Intel StrongARM strongarm-*-*
5040 Mitsubishi D30V d30v-*-*
5042 * OBSOLETE configurations
5044 Gould PowerNode, NP1 np1-*-*, pn-*-*
5046 Configurations that have been declared obsolete will be commented out,
5047 but the code will be left in place. If there is no activity to revive
5048 these configurations before the next release of GDB, the sources will
5049 be permanently REMOVED.
5053 As a compatibility experiment, GDB's source files buildsym.h and
5054 buildsym.c have been converted to pure standard C, no longer
5055 containing any K&R compatibility code. We believe that all systems in
5056 use today either come with a standard C compiler, or have a GCC port
5057 available. If this is not true, please report the affected
5058 configuration to bug-gdb@gnu.org immediately. See the README file for
5059 information about getting a standard C compiler if you don't have one
5064 GDB now uses readline 2.2.
5066 * set extension-language
5068 You can now control the mapping between filename extensions and source
5069 languages by using the `set extension-language' command. For instance,
5070 you can ask GDB to treat .c files as C++ by saying
5071 set extension-language .c c++
5072 The command `info extensions' lists all of the recognized extensions
5073 and their associated languages.
5075 * Setting processor type for PowerPC and RS/6000
5077 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5078 you can use the `set processor' command to specify what variant of the
5079 PowerPC family you are debugging. The command
5083 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5084 following PowerPC and RS6000 variants:
5086 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5087 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5089 403GC IBM PowerPC 403GC
5090 505 Motorola PowerPC 505
5091 860 Motorola PowerPC 860 or 850
5092 601 Motorola PowerPC 601
5093 602 Motorola PowerPC 602
5094 603 Motorola/IBM PowerPC 603 or 603e
5095 604 Motorola PowerPC 604 or 604e
5096 750 Motorola/IBM PowerPC 750 or 750
5098 At the moment, this command just tells GDB what to name the
5099 special-purpose processor registers. Since almost all the affected
5100 registers are inaccessible to user-level programs, this command is
5101 only useful for remote debugging in its present form.
5105 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5106 more extensive support for HP-UX. Added features include shared
5107 library support, kernel threads and hardware watchpoints for 11.00,
5108 support for HP's ANSI C and C++ compilers, and a compatibility mode
5109 for xdb and dbx commands.
5113 HP's donation includes the new concept of catchpoints, which is a
5114 generalization of the old catch command. On HP-UX, it is now possible
5115 to catch exec, fork, and vfork, as well as library loading.
5117 This means that the existing catch command has changed; its first
5118 argument now specifies the type of catch to be set up. See the
5119 output of "help catch" for a list of catchpoint types.
5121 * Debugging across forks
5123 On HP-UX, you can choose which process to debug when a fork() happens
5128 HP has donated a curses-based terminal user interface (TUI). To get
5129 it, build with --enable-tui. Although this can be enabled for any
5130 configuration, at present it only works for native HP debugging.
5132 * GDB remote protocol additions
5134 A new protocol packet 'X' that writes binary data is now available.
5135 Default behavior is to try 'X', then drop back to 'M' if the stub
5136 fails to respond. The settable variable `remotebinarydownload'
5137 allows explicit control over the use of 'X'.
5139 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5140 full 64-bit address. The command
5142 set remoteaddresssize 32
5144 can be used to revert to the old behaviour. For existing remote stubs
5145 the change should not be noticed, as the additional address information
5148 In order to assist in debugging stubs, you may use the maintenance
5149 command `packet' to send any text string to the stub. For instance,
5151 maint packet heythere
5153 sends the packet "$heythere#<checksum>". Note that it is very easy to
5154 disrupt a debugging session by sending the wrong packet at the wrong
5157 The compare-sections command allows you to compare section data on the
5158 target to what is in the executable file without uploading or
5159 downloading, by comparing CRC checksums.
5161 * Tracing can collect general expressions
5163 You may now collect general expressions at tracepoints. This requires
5164 further additions to the target-side stub; see tracepoint.c and
5165 doc/agentexpr.texi for further details.
5167 * mask-address variable for Mips
5169 For Mips targets, you may control the zeroing of the upper 32 bits of
5170 a 64-bit address by entering `set mask-address on'. This is mainly
5171 of interest to users of embedded R4xxx and R5xxx processors.
5173 * Higher serial baud rates
5175 GDB's serial code now allows you to specify baud rates 57600, 115200,
5176 230400, and 460800 baud. (Note that your host system may not be able
5177 to achieve all of these rates.)
5181 The i960 configuration now includes an initial implementation of a
5182 builtin simulator, contributed by Jim Wilson.
5185 *** Changes in GDB-4.17:
5187 * New native configurations
5189 Alpha GNU/Linux alpha*-*-linux*
5190 Unixware 2.x i[3456]86-unixware2*
5191 Irix 6.x mips*-sgi-irix6*
5192 PowerPC GNU/Linux powerpc-*-linux*
5193 PowerPC Solaris powerpcle-*-solaris*
5194 Sparc GNU/Linux sparc-*-linux*
5195 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5199 Argonaut Risc Chip (ARC) arc-*-*
5200 Hitachi H8/300S h8300*-*-*
5201 Matsushita MN10200 w/simulator mn10200-*-*
5202 Matsushita MN10300 w/simulator mn10300-*-*
5203 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5204 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5205 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5206 Mitsubishi D10V w/simulator d10v-*-*
5207 Mitsubishi M32R/D w/simulator m32r-*-elf*
5208 Tsqware Sparclet sparclet-*-*
5209 NEC V850 w/simulator v850-*-*
5211 * New debugging protocols
5213 ARM with RDI protocol arm*-*-*
5214 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5215 DDB and LSI variants of PMON protocol mips*-*-*
5216 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5217 PowerPC with SDS protocol powerpc{,le}-*-eabi
5218 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5222 All configurations can now understand and use the DWARF 2 debugging
5223 format. The choice is automatic, if the symbol file contains DWARF 2
5228 GDB now includes basic Java language support. This support is
5229 only useful with Java compilers that produce native machine code.
5231 * solib-absolute-prefix and solib-search-path
5233 For SunOS and SVR4 shared libraries, you may now set the prefix for
5234 loading absolute shared library symbol files, and the search path for
5235 locating non-absolute shared library symbol files.
5237 * Live range splitting
5239 GDB can now effectively debug code for which GCC has performed live
5240 range splitting as part of its optimization. See gdb/doc/LRS for
5241 more details on the expected format of the stabs information.
5245 GDB's support for the GNU Hurd, including thread debugging, has been
5246 updated to work with current versions of the Hurd.
5250 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5251 instruction set. ARM GDB automatically detects when Thumb
5252 instructions are in use, and adjusts disassembly and backtracing
5257 GDB's MIPS target configurations now handle the MIP16 16-bit
5262 GDB now includes support for overlays; if an executable has been
5263 linked such that multiple sections are based at the same address, GDB
5264 will decide which section to use for symbolic info. You can choose to
5265 control the decision manually, using overlay commands, or implement
5266 additional target-side support and use "overlay load-target" to bring
5267 in the overlay mapping. Do "help overlay" for more detail.
5271 The command "info symbol <address>" displays information about
5272 the symbol at the specified address.
5276 The standard remote protocol now includes an extension that allows
5277 asynchronous collection and display of trace data. This requires
5278 extensive support in the target-side debugging stub. Tracing mode
5279 includes a new interaction mode in GDB and new commands: see the
5280 file tracepoint.c for more details.
5284 Configurations for embedded MIPS now include a simulator contributed
5285 by Cygnus Solutions. The simulator supports the instruction sets
5286 of most MIPS variants.
5290 Sparc configurations may now include the ERC32 simulator contributed
5291 by the European Space Agency. The simulator is not built into
5292 Sparc targets by default; configure with --enable-sim to include it.
5296 For target configurations that may include multiple variants of a
5297 basic architecture (such as MIPS and SH), you may now set the
5298 architecture explicitly. "set arch" sets, "info arch" lists
5299 the possible architectures.
5301 *** Changes in GDB-4.16:
5303 * New native configurations
5305 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5306 M68K NetBSD m68k-*-netbsd*
5307 PowerPC AIX 4.x powerpc-*-aix*
5308 PowerPC MacOS powerpc-*-macos*
5309 PowerPC Windows NT powerpcle-*-cygwin32
5310 RS/6000 AIX 4.x rs6000-*-aix4*
5314 ARM with RDP protocol arm-*-*
5315 I960 with MON960 i960-*-coff
5316 MIPS VxWorks mips*-*-vxworks*
5317 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5318 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5320 Matra Sparclet sparclet-*-*
5324 The powerpc-eabi configuration now includes the PSIM simulator,
5325 contributed by Andrew Cagney, with assistance from Mike Meissner.
5326 PSIM is a very elaborate model of the PowerPC, including not only
5327 basic instruction set execution, but also details of execution unit
5328 performance and I/O hardware. See sim/ppc/README for more details.
5332 GDB now works with Solaris 2.5.
5334 * Windows 95/NT native
5336 GDB will now work as a native debugger on Windows 95 and Windows NT.
5337 To build it from source, you must use the "gnu-win32" environment,
5338 which uses a DLL to emulate enough of Unix to run the GNU tools.
5339 Further information, binaries, and sources are available at
5340 ftp.cygnus.com, under pub/gnu-win32.
5342 * dont-repeat command
5344 If a user-defined command includes the command `dont-repeat', then the
5345 command will not be repeated if the user just types return. This is
5346 useful if the command is time-consuming to run, so that accidental
5347 extra keystrokes don't run the same command many times.
5349 * Send break instead of ^C
5351 The standard remote protocol now includes an option to send a break
5352 rather than a ^C to the target in order to interrupt it. By default,
5353 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5355 * Remote protocol timeout
5357 The standard remote protocol includes a new variable `remotetimeout'
5358 that allows you to set the number of seconds before GDB gives up trying
5359 to read from the target. The default value is 2.
5361 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5363 By default GDB will automatically keep track of objects as they are
5364 loaded and unloaded by the dynamic linker. By using the command `set
5365 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5366 when shared library events occur, thus allowing you to set breakpoints
5367 in shared libraries which are explicitly loaded by the inferior.
5369 Note this feature does not work on hpux8. On hpux9 you must link
5370 /usr/lib/end.o into your program. This feature should work
5371 automatically on hpux10.
5373 * Irix 5.x hardware watchpoint support
5375 Irix 5 configurations now support the use of hardware watchpoints.
5377 * Mips protocol "SYN garbage limit"
5379 When debugging a Mips target using the `target mips' protocol, you
5380 may set the number of characters that GDB will ignore by setting
5381 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5382 every character. The default value is 1050.
5384 * Recording and replaying remote debug sessions
5386 If you set `remotelogfile' to the name of a file, gdb will write to it
5387 a recording of a remote debug session. This recording may then be
5388 replayed back to gdb using "gdbreplay". See gdbserver/README for
5389 details. This is useful when you have a problem with GDB while doing
5390 remote debugging; you can make a recording of the session and send it
5391 to someone else, who can then recreate the problem.
5393 * Speedups for remote debugging
5395 GDB includes speedups for downloading and stepping MIPS systems using
5396 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5397 and more efficient S-record downloading.
5399 * Memory use reductions and statistics collection
5401 GDB now uses less memory and reports statistics about memory usage.
5402 Try the `maint print statistics' command, for example.
5404 *** Changes in GDB-4.15:
5406 * Psymtabs for XCOFF
5408 The symbol reader for AIX GDB now uses partial symbol tables. This
5409 can greatly improve startup time, especially for large executables.
5411 * Remote targets use caching
5413 Remote targets now use a data cache to speed up communication with the
5414 remote side. The data cache could lead to incorrect results because
5415 it doesn't know about volatile variables, thus making it impossible to
5416 debug targets which use memory mapped I/O devices. `set remotecache
5417 off' turns the the data cache off.
5419 * Remote targets may have threads
5421 The standard remote protocol now includes support for multiple threads
5422 in the target system, using new protocol commands 'H' and 'T'. See
5423 gdb/remote.c for details.
5427 If GDB is configured with `--enable-netrom', then it will include
5428 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5429 acts as though it is a bank of ROM on the target board, but you can
5430 write into it over the network. GDB's support consists only of
5431 support for fast loading into the emulated ROM; to debug, you must use
5432 another protocol, such as standard remote protocol. The usual
5433 sequence is something like
5435 target nrom <netrom-hostname>
5437 target remote <netrom-hostname>:1235
5441 GDB now includes support for the Apple Macintosh, as a host only. It
5442 may be run as either an MPW tool or as a standalone application, and
5443 it can debug through the serial port. All the usual GDB commands are
5444 available, but to the target command, you must supply "serial" as the
5445 device type instead of "/dev/ttyXX". See mpw-README in the main
5446 directory for more information on how to build. The MPW configuration
5447 scripts */mpw-config.in support only a few targets, and only the
5448 mips-idt-ecoff target has been tested.
5452 GDB configuration now uses autoconf. This is not user-visible,
5453 but does simplify configuration and building.
5457 GDB now supports hpux10.
5459 *** Changes in GDB-4.14:
5461 * New native configurations
5463 x86 FreeBSD i[345]86-*-freebsd
5464 x86 NetBSD i[345]86-*-netbsd
5465 NS32k NetBSD ns32k-*-netbsd
5466 Sparc NetBSD sparc-*-netbsd
5470 A29K VxWorks a29k-*-vxworks
5471 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5472 CPU32 EST-300 emulator m68*-*-est*
5473 PowerPC ELF powerpc-*-elf
5476 * Alpha OSF/1 support for procfs
5478 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5479 possible to attach to running processes. As the mounting of the /proc
5480 filesystem is optional on the Alpha, GDB automatically determines
5481 the availability of /proc during startup. This can lead to problems
5482 if /proc is unmounted after GDB has been started.
5484 * Arguments to user-defined commands
5486 User commands may accept up to 10 arguments separated by whitespace.
5487 Arguments are accessed within the user command via $arg0..$arg9. A
5490 print $arg0 + $arg1 + $arg2
5492 To execute the command use:
5495 Defines the command "adder" which prints the sum of its three arguments.
5496 Note the arguments are text substitutions, so they may reference variables,
5497 use complex expressions, or even perform inferior function calls.
5499 * New `if' and `while' commands
5501 This makes it possible to write more sophisticated user-defined
5502 commands. Both commands take a single argument, which is the
5503 expression to evaluate, and must be followed by the commands to
5504 execute, one per line, if the expression is nonzero, the list being
5505 terminated by the word `end'. The `if' command list may include an
5506 `else' word, which causes the following commands to be executed only
5507 if the expression is zero.
5509 * Fortran source language mode
5511 GDB now includes partial support for Fortran 77. It will recognize
5512 Fortran programs and can evaluate a subset of Fortran expressions, but
5513 variables and functions may not be handled correctly. GDB will work
5514 with G77, but does not yet know much about symbols emitted by other
5517 * Better HPUX support
5519 Most debugging facilities now work on dynamic executables for HPPAs
5520 running hpux9 or later. You can attach to running dynamically linked
5521 processes, but by default the dynamic libraries will be read-only, so
5522 for instance you won't be able to put breakpoints in them. To change
5523 that behavior do the following before running the program:
5529 This will cause the libraries to be mapped private and read-write.
5530 To revert to the normal behavior, do this:
5536 You cannot set breakpoints or examine data in the library until after
5537 the library is loaded if the function/data symbols do not have
5540 GDB can now also read debug symbols produced by the HP C compiler on
5541 HPPAs (sorry, no C++, Fortran or 68k support).
5543 * Target byte order now dynamically selectable
5545 You can choose which byte order to use with a target system, via the
5546 commands "set endian big" and "set endian little", and you can see the
5547 current setting by using "show endian". You can also give the command
5548 "set endian auto", in which case GDB will use the byte order
5549 associated with the executable. Currently, only embedded MIPS
5550 configurations support dynamic selection of target byte order.
5552 * New DOS host serial code
5554 This version uses DPMI interrupts to handle buffered I/O, so you
5555 no longer need to run asynctsr when debugging boards connected to
5558 *** Changes in GDB-4.13:
5560 * New "complete" command
5562 This lists all the possible completions for the rest of the line, if it
5563 were to be given as a command itself. This is intended for use by emacs.
5565 * Trailing space optional in prompt
5567 "set prompt" no longer adds a space for you after the prompt you set. This
5568 allows you to set a prompt which ends in a space or one that does not.
5570 * Breakpoint hit counts
5572 "info break" now displays a count of the number of times the breakpoint
5573 has been hit. This is especially useful in conjunction with "ignore"; you
5574 can ignore a large number of breakpoint hits, look at the breakpoint info
5575 to see how many times the breakpoint was hit, then run again, ignoring one
5576 less than that number, and this will get you quickly to the last hit of
5579 * Ability to stop printing at NULL character
5581 "set print null-stop" will cause GDB to stop printing the characters of
5582 an array when the first NULL is encountered. This is useful when large
5583 arrays actually contain only short strings.
5585 * Shared library breakpoints
5587 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5588 breakpoints in shared libraries before the executable is run.
5590 * Hardware watchpoints
5592 There is a new hardware breakpoint for the watch command for sparclite
5593 targets. See gdb/sparclite/hw_breakpoint.note.
5595 Hardware watchpoints are also now supported under GNU/Linux.
5599 Annotations have been added. These are for use with graphical interfaces,
5600 and are still experimental. Currently only gdba.el uses these.
5602 * Improved Irix 5 support
5604 GDB now works properly with Irix 5.2.
5606 * Improved HPPA support
5608 GDB now works properly with the latest GCC and GAS.
5610 * New native configurations
5612 Sequent PTX4 i[34]86-sequent-ptx4
5613 HPPA running OSF/1 hppa*-*-osf*
5614 Atari TT running SVR4 m68*-*-sysv4*
5615 RS/6000 LynxOS rs6000-*-lynxos*
5619 OS/9000 i[34]86-*-os9k
5620 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5623 * Hitachi SH7000 and E7000-PC ICE support
5625 There is now support for communicating with the Hitachi E7000-PC ICE.
5626 This is available automatically when GDB is configured for the SH.
5630 As usual, a variety of small fixes and improvements, both generic
5631 and configuration-specific. See the ChangeLog for more detail.
5633 *** Changes in GDB-4.12:
5635 * Irix 5 is now supported
5639 GDB-4.12 on the HPPA has a number of changes which make it unable
5640 to debug the output from the currently released versions of GCC and
5641 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5642 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5643 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5646 *** Changes in GDB-4.11:
5648 * User visible changes:
5652 The "set remotedebug" option is now consistent between the mips remote
5653 target, remote targets using the gdb-specific protocol, UDI (AMD's
5654 debug protocol for the 29k) and the 88k bug monitor. It is now an
5655 integer specifying a debug level (normally 0 or 1, but 2 means more
5656 debugging info for the mips target).
5658 * DEC Alpha native support
5660 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5661 debug info, but GDB works fairly well with the DEC compiler and should
5662 work with a future GCC release. See the README file for a few
5663 Alpha-specific notes.
5665 * Preliminary thread implementation
5667 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5669 * LynxOS native and target support for 386
5671 This release has been hosted on LynxOS 2.2, and also can be configured
5672 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5675 * Improvements in C++ mangling/demangling.
5677 This release has much better g++ debugging, specifically in name
5678 mangling/demangling, virtual function calls, print virtual table,
5679 call methods, ...etc.
5681 *** Changes in GDB-4.10:
5683 * User visible changes:
5685 Remote debugging using the GDB-specific (`target remote') protocol now
5686 supports the `load' command. This is only useful if you have some
5687 other way of getting the stub to the target system, and you can put it
5688 somewhere in memory where it won't get clobbered by the download.
5690 Filename completion now works.
5692 When run under emacs mode, the "info line" command now causes the
5693 arrow to point to the line specified. Also, "info line" prints
5694 addresses in symbolic form (as well as hex).
5696 All vxworks based targets now support a user settable option, called
5697 vxworks-timeout. This option represents the number of seconds gdb
5698 should wait for responses to rpc's. You might want to use this if
5699 your vxworks target is, perhaps, a slow software simulator or happens
5700 to be on the far side of a thin network line.
5704 This release contains support for using a DEC alpha as a GDB host for
5705 cross debugging. Native alpha debugging is not supported yet.
5708 *** Changes in GDB-4.9:
5712 This is the first GDB release which is accompanied by a matching testsuite.
5713 The testsuite requires installation of dejagnu, which should be available
5714 via ftp from most sites that carry GNU software.
5718 'Cfront' style demangling has had its name changed to 'ARM' style, to
5719 emphasize that it was written from the specifications in the C++ Annotated
5720 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5721 disclaimers, it still generated too much confusion with users attempting to
5722 use gdb with AT&T cfront.
5726 GDB now uses a standard remote interface to a simulator library.
5727 So far, the library contains simulators for the Zilog Z8001/2, the
5728 Hitachi H8/300, H8/500 and Super-H.
5730 * New targets supported
5732 H8/300 simulator h8300-hitachi-hms or h8300hms
5733 H8/500 simulator h8500-hitachi-hms or h8500hms
5734 SH simulator sh-hitachi-hms or sh
5735 Z8000 simulator z8k-zilog-none or z8ksim
5736 IDT MIPS board over serial line mips-idt-ecoff
5738 Cross-debugging to GO32 targets is supported. It requires a custom
5739 version of the i386-stub.c module which is integrated with the
5740 GO32 memory extender.
5742 * New remote protocols
5744 MIPS remote debugging protocol.
5746 * New source languages supported
5748 This version includes preliminary support for Chill, a Pascal like language
5749 used by telecommunications companies. Chill support is also being integrated
5750 into the GNU compiler, but we don't know when it will be publically available.
5753 *** Changes in GDB-4.8:
5755 * HP Precision Architecture supported
5757 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5758 version of this support was available as a set of patches from the
5759 University of Utah. GDB does not support debugging of programs
5760 compiled with the HP compiler, because HP will not document their file
5761 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5762 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5764 Many problems in the preliminary version have been fixed.
5766 * Faster and better demangling
5768 We have improved template demangling and fixed numerous bugs in the GNU style
5769 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5770 character types (wchar_t) are now supported. Demangling of each symbol is now
5771 only done once, and is cached when the symbol table for a file is read in.
5772 This results in a small increase in memory usage for C programs, a moderate
5773 increase in memory usage for C++ programs, and a fantastic speedup in
5776 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5777 from the specifications in the Annotated Reference Manual, which AT&T's
5778 compiler does not actually implement.
5780 * G++ multiple inheritance compiler problem
5782 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5783 inheritance lattices was reworked to properly discover ambiguities. We
5784 recently found an example which causes this new algorithm to fail in a
5785 very subtle way, producing bad debug information for those classes.
5786 The file 'gcc.patch' (in this directory) can be applied to gcc to
5787 circumvent the problem. A future GCC release will contain a complete
5790 The previous G++ debug info problem (mentioned below for the gdb-4.7
5791 release) is fixed in gcc version 2.3.2.
5793 * Improved configure script
5795 The `configure' script will now attempt to guess your system type if
5796 you don't supply a host system type. The old scheme of supplying a
5797 host system triplet is preferable over using this. All the magic is
5798 done in the new `config.guess' script. Examine it for details.
5800 We have also brought our configure script much more in line with the FSF's
5801 version. It now supports the --with-xxx options. In particular,
5802 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5803 The resulting GDB will not be able to read arbitrary object file formats --
5804 only the format ``expected'' to be used on the configured target system.
5805 We hope to make this the default in a future release.
5807 * Documentation improvements
5809 There's new internal documentation on how to modify GDB, and how to
5810 produce clean changes to the code. We implore people to read it
5811 before submitting changes.
5813 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
5814 M4 macros. The new texinfo.tex is provided in this release. Pre-built
5815 `info' files are also provided. To build `info' files from scratch,
5816 you will need the latest `makeinfo' release, which will be available in
5817 a future texinfo-X.Y release.
5819 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
5820 We're not sure exactly which versions have this problem, but it has
5821 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
5822 or better. If that isn't possible, there is a patch in
5823 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
5824 around this problem.
5828 GDB now supports array constants that can be used in expressions typed in by
5829 the user. The syntax is `{element, element, ...}'. Ie: you can now type
5830 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
5833 The new directory `gdb/sparclite' contains a program that demonstrates
5834 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
5836 * New native hosts supported
5838 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
5839 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
5841 * New targets supported
5843 AMD 29k family via UDI a29k-amd-udi or udi29k
5845 * New file formats supported
5847 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5848 HPUX core files, and SCO 3.2v2 core files.
5852 Attaching to processes now works again; thanks for the many bug reports.
5854 We have also stomped on a bunch of core dumps caused by
5855 printf_filtered("%s") problems.
5857 We eliminated a copyright problem on the rpc and ptrace header files
5858 for VxWorks, which was discovered at the last minute during the 4.7
5859 release. You should now be able to build a VxWorks GDB.
5861 You can now interrupt gdb while an attached process is running. This
5862 will cause the attached process to stop, and give control back to GDB.
5864 We fixed problems caused by using too many file descriptors
5865 for reading symbols from object files and libraries. This was
5866 especially a problem for programs that used many (~100) shared
5869 The `step' command now only enters a subroutine if there is line number
5870 information for the subroutine. Otherwise it acts like the `next'
5871 command. Previously, `step' would enter subroutines if there was
5872 any debugging information about the routine. This avoids problems
5873 when using `cc -g1' on MIPS machines.
5875 * Internal improvements
5877 GDB's internal interfaces have been improved to make it easier to support
5878 debugging of multiple languages in the future.
5880 GDB now uses a common structure for symbol information internally.
5881 Minimal symbols (derived from linkage symbols in object files), partial
5882 symbols (from a quick scan of debug information), and full symbols
5883 contain a common subset of information, making it easier to write
5884 shared code that handles any of them.
5886 * New command line options
5888 We now accept --silent as an alias for --quiet.
5892 The memory-mapped-malloc library is now licensed under the GNU Library
5893 General Public License.
5895 *** Changes in GDB-4.7:
5897 * Host/native/target split
5899 GDB has had some major internal surgery to untangle the support for
5900 hosts and remote targets. Now, when you configure GDB for a remote
5901 target, it will no longer load in all of the support for debugging
5902 local programs on the host. When fully completed and tested, this will
5903 ensure that arbitrary host/target combinations are possible.
5905 The primary conceptual shift is to separate the non-portable code in
5906 GDB into three categories. Host specific code is required any time GDB
5907 is compiled on that host, regardless of the target. Target specific
5908 code relates to the peculiarities of the target, but can be compiled on
5909 any host. Native specific code is everything else: it can only be
5910 built when the host and target are the same system. Child process
5911 handling and core file support are two common `native' examples.
5913 GDB's use of /proc for controlling Unix child processes is now cleaner.
5914 It has been split out into a single module under the `target_ops' vector,
5915 plus two native-dependent functions for each system that uses /proc.
5917 * New hosts supported
5919 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5920 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5921 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5923 * New targets supported
5925 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5926 68030 and CPU32 m68030-*-*, m68332-*-*
5928 * New native hosts supported
5930 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5931 (386bsd is not well tested yet)
5932 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5934 * New file formats supported
5936 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5937 supports reading of `a.out.adobe' object files, which are an a.out
5938 format extended with minimal information about multiple sections.
5942 `show copying' is the same as the old `info copying'.
5943 `show warranty' is the same as `info warrantee'.
5944 These were renamed for consistency. The old commands continue to work.
5946 `info handle' is a new alias for `info signals'.
5948 You can now define pre-command hooks, which attach arbitrary command
5949 scripts to any command. The commands in the hook will be executed
5950 prior to the user's command. You can also create a hook which will be
5951 executed whenever the program stops. See gdb.texinfo.
5955 We now deal with Cfront style name mangling, and can even extract type
5956 info from mangled symbols. GDB can automatically figure out which
5957 symbol mangling style your C++ compiler uses.
5959 Calling of methods and virtual functions has been improved as well.
5963 The crash that occured when debugging Sun Ansi-C compiled binaries is
5964 fixed. This was due to mishandling of the extra N_SO stabs output
5967 We also finally got Ultrix 4.2 running in house, and fixed core file
5968 support, with help from a dozen people on the net.
5970 John M. Farrell discovered that the reason that single-stepping was so
5971 slow on all of the Mips based platforms (primarily SGI and DEC) was
5972 that we were trying to demangle and lookup a symbol used for internal
5973 purposes on every instruction that was being stepped through. Changing
5974 the name of that symbol so that it couldn't be mistaken for a C++
5975 mangled symbol sped things up a great deal.
5977 Rich Pixley sped up symbol lookups in general by getting much smarter
5978 about when C++ symbol mangling is necessary. This should make symbol
5979 completion (TAB on the command line) much faster. It's not as fast as
5980 we'd like, but it's significantly faster than gdb-4.6.
5984 A new user controllable variable 'call_scratch_address' can
5985 specify the location of a scratch area to be used when GDB
5986 calls a function in the target. This is necessary because the
5987 usual method of putting the scratch area on the stack does not work
5988 in systems that have separate instruction and data spaces.
5990 We integrated changes to support the 29k UDI (Universal Debugger
5991 Interface), but discovered at the last minute that we didn't have all
5992 of the appropriate copyright paperwork. We are working with AMD to
5993 resolve this, and hope to have it available soon.
5997 We have sped up the remote serial line protocol, especially for targets
5998 with lots of registers. It now supports a new `expedited status' ('T')
5999 message which can be used in place of the existing 'S' status message.
6000 This allows the remote stub to send only the registers that GDB
6001 needs to make a quick decision about single-stepping or conditional
6002 breakpoints, eliminating the need to fetch the entire register set for
6003 each instruction being stepped through.
6005 The GDB remote serial protocol now implements a write-through cache for
6006 registers, only re-reading the registers if the target has run.
6008 There is also a new remote serial stub for SPARC processors. You can
6009 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6010 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6011 processor with a serial port.
6015 Configure.in files have become much easier to read and modify. A new
6016 `table driven' format makes it more obvious what configurations are
6017 supported, and what files each one uses.
6021 There is a new opcodes library which will eventually contain all of the
6022 disassembly routines and opcode tables. At present, it only contains
6023 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6024 disassembler (binutils/objdump) to share these routines.
6026 The libiberty library is now copylefted under the GNU Library General
6027 Public License. This allows more liberal use, and was done so libg++
6028 can use it. This makes no difference to GDB, since the Library License
6029 grants all the rights from the General Public License.
6033 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6034 reference to the stabs symbol info used by the debugger. It is (as far
6035 as we know) the only published document on this fascinating topic. We
6036 encourage you to read it, compare it to the stabs information on your
6037 system, and send improvements on the document in general (to
6038 bug-gdb@prep.ai.mit.edu).
6040 And, of course, many bugs have been fixed.
6043 *** Changes in GDB-4.6:
6045 * Better support for C++ function names
6047 GDB now accepts as input the "demangled form" of C++ overloaded function
6048 names and member function names, and can do command completion on such names
6049 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6050 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6051 Make use of command completion, it is your friend.
6053 GDB also now accepts a variety of C++ mangled symbol formats. They are
6054 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6055 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6056 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6057 for the list of formats.
6059 * G++ symbol mangling problem
6061 Recent versions of gcc have a bug in how they emit debugging information for
6062 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6063 directory) can be applied to gcc to fix the problem. Alternatively, if you
6064 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6065 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6066 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6069 * New 'maintenance' command
6071 All of the commands related to hacking GDB internals have been moved out of
6072 the main command set, and now live behind the 'maintenance' command. This
6073 can also be abbreviated as 'mt'. The following changes were made:
6075 dump-me -> maintenance dump-me
6076 info all-breakpoints -> maintenance info breakpoints
6077 printmsyms -> maintenance print msyms
6078 printobjfiles -> maintenance print objfiles
6079 printpsyms -> maintenance print psymbols
6080 printsyms -> maintenance print symbols
6082 The following commands are new:
6084 maintenance demangle Call internal GDB demangler routine to
6085 demangle a C++ link name and prints the result.
6086 maintenance print type Print a type chain for a given symbol
6088 * Change to .gdbinit file processing
6090 We now read the $HOME/.gdbinit file before processing the argv arguments
6091 (e.g. reading symbol files or core files). This allows global parameters to
6092 be set, which will apply during the symbol reading. The ./.gdbinit is still
6093 read after argv processing.
6095 * New hosts supported
6097 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6099 GNU/Linux support i386-unknown-linux or linux
6101 We are also including code to support the HP/PA running BSD and HPUX. This
6102 is almost guaranteed not to work, as we didn't have time to test or build it
6103 for this release. We are including it so that the more adventurous (or
6104 masochistic) of you can play with it. We also had major problems with the
6105 fact that the compiler that we got from HP doesn't support the -g option.
6108 * New targets supported
6110 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6112 * More smarts about finding #include files
6114 GDB now remembers the compilation directory for all include files, and for
6115 all files from which C is generated (like yacc and lex sources). This
6116 greatly improves GDB's ability to find yacc/lex sources, and include files,
6117 especially if you are debugging your program from a directory different from
6118 the one that contains your sources.
6120 We also fixed a bug which caused difficulty with listing and setting
6121 breakpoints in include files which contain C code. (In the past, you had to
6122 try twice in order to list an include file that you hadn't looked at before.)
6124 * Interesting infernals change
6126 GDB now deals with arbitrary numbers of sections, where the symbols for each
6127 section must be relocated relative to that section's landing place in the
6128 target's address space. This work was needed to support ELF with embedded
6129 stabs used by Solaris-2.0.
6131 * Bug fixes (of course!)
6133 There have been loads of fixes for the following things:
6134 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6135 i960, stabs, DOS(GO32), procfs, etc...
6137 See the ChangeLog for details.
6139 *** Changes in GDB-4.5:
6141 * New machines supported (host and target)
6143 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6145 SGI Irix-4.x mips-sgi-irix4 or iris4
6147 * New malloc package
6149 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6150 Mmalloc is capable of handling mutiple heaps of memory. It is also
6151 capable of saving a heap to a file, and then mapping it back in later.
6152 This can be used to greatly speedup the startup of GDB by using a
6153 pre-parsed symbol table which lives in a mmalloc managed heap. For
6154 more details, please read mmalloc/mmalloc.texi.
6158 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6159 'help info proc' for details.
6161 * MIPS ecoff symbol table format
6163 The code that reads MIPS symbol table format is now supported on all hosts.
6164 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6167 * File name changes for MS-DOS
6169 Many files in the config directories have been renamed to make it easier to
6170 support GDB on MS-DOSe systems (which have very restrictive file name
6171 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6172 environment) is close to working but has some remaining problems. Note
6173 that debugging of DOS programs is not supported, due to limitations
6174 in the ``operating system'', but it can be used to host cross-debugging.
6176 * Cross byte order fixes
6178 Many fixes have been made to support cross debugging of Sparc and MIPS
6179 targets from hosts whose byte order differs.
6181 * New -mapped and -readnow options
6183 If memory-mapped files are available on your system through the 'mmap'
6184 system call, you can use the -mapped option on the `file' or
6185 `symbol-file' commands to cause GDB to write the symbols from your
6186 program into a reusable file. If the program you are debugging is
6187 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6188 Future GDB debugging sessions will notice the presence of this file,
6189 and will quickly map in symbol information from it, rather than reading
6190 the symbol table from the executable program. Using the '-mapped'
6191 option in a GDB `file' or `symbol-file' command has the same effect as
6192 starting GDB with the '-mapped' command-line option.
6194 You can cause GDB to read the entire symbol table immediately by using
6195 the '-readnow' option with any of the commands that load symbol table
6196 information (or on the GDB command line). This makes the command
6197 slower, but makes future operations faster.
6199 The -mapped and -readnow options are typically combined in order to
6200 build a `fred.syms' file that contains complete symbol information.
6201 A simple GDB invocation to do nothing but build a `.syms' file for future
6204 gdb -batch -nx -mapped -readnow programname
6206 The `.syms' file is specific to the host machine on which GDB is run.
6207 It holds an exact image of GDB's internal symbol table. It cannot be
6208 shared across multiple host platforms.
6210 * longjmp() handling
6212 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6213 siglongjmp() without losing control. This feature has not yet been ported to
6214 all systems. It currently works on many 386 platforms, all MIPS-based
6215 platforms (SGI, DECstation, etc), and Sun3/4.
6219 Preliminary work has been put in to support the new Solaris OS from Sun. At
6220 this time, it can control and debug processes, but it is not capable of
6225 As always, many many bug fixes. The major areas were with g++, and mipsread.
6226 People using the MIPS-based platforms should experience fewer mysterious
6227 crashes and trashed symbol tables.
6229 *** Changes in GDB-4.4:
6231 * New machines supported (host and target)
6233 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6235 BSD Reno on Vax vax-dec-bsd
6236 Ultrix on Vax vax-dec-ultrix
6238 * New machines supported (target)
6240 AMD 29000 embedded, using EBMON a29k-none-none
6244 GDB continues to improve its handling of C++. `References' work better.
6245 The demangler has also been improved, and now deals with symbols mangled as
6246 per the Annotated C++ Reference Guide.
6248 GDB also now handles `stabs' symbol information embedded in MIPS
6249 `ecoff' symbol tables. Since the ecoff format was not easily
6250 extensible to handle new languages such as C++, this appeared to be a
6251 good way to put C++ debugging info into MIPS binaries. This option
6252 will be supported in the GNU C compiler, version 2, when it is
6255 * New features for SVR4
6257 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6258 shared libraries. Debugging dynamically linked programs should present
6259 only minor differences from debugging statically linked programs.
6261 The `info proc' command will print out information about any process
6262 on an SVR4 system (including the one you are debugging). At the moment,
6263 it prints the address mappings of the process.
6265 If you bring up GDB on another SVR4 system, please send mail to
6266 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6268 * Better dynamic linking support in SunOS
6270 Reading symbols from shared libraries which contain debugging symbols
6271 now works properly. However, there remain issues such as automatic
6272 skipping of `transfer vector' code during function calls, which
6273 make it harder to debug code in a shared library, than to debug the
6274 same code linked statically.
6278 GDB is now using the latest `getopt' routines from the FSF. This
6279 version accepts the -- prefix for options with long names. GDB will
6280 continue to accept the old forms (-option and +option) as well.
6281 Various single letter abbreviations for options have been explicity
6282 added to the option table so that they won't get overshadowed in the
6283 future by other options that begin with the same letter.
6287 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6288 Many assorted bugs have been handled. Many more remain to be handled.
6289 See the various ChangeLog files (primarily in gdb and bfd) for details.
6292 *** Changes in GDB-4.3:
6294 * New machines supported (host and target)
6296 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6297 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6298 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6300 * Almost SCO Unix support
6302 We had hoped to support:
6303 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6304 (except for core file support), but we discovered very late in the release
6305 that it has problems with process groups that render gdb unusable. Sorry
6306 about that. I encourage people to fix it and post the fixes.
6308 * Preliminary ELF and DWARF support
6310 GDB can read ELF object files on System V Release 4, and can handle
6311 debugging records for C, in DWARF format, in ELF files. This support
6312 is preliminary. If you bring up GDB on another SVR4 system, please
6313 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6318 GDB now uses the latest `readline' library. One user-visible change
6319 is that two tabs will list possible command completions, which previously
6320 required typing M-? (meta-question mark, or ESC ?).
6324 The `stepi' bug that many of you noticed has been squashed.
6325 Many bugs in C++ have been handled. Many more remain to be handled.
6326 See the various ChangeLog files (primarily in gdb and bfd) for details.
6328 * State of the MIPS world (in case you wondered):
6330 GDB can understand the symbol tables emitted by the compilers
6331 supplied by most vendors of MIPS-based machines, including DEC. These
6332 symbol tables are in a format that essentially nobody else uses.
6334 Some versions of gcc come with an assembler post-processor called
6335 mips-tfile. This program is required if you want to do source-level
6336 debugging of gcc-compiled programs. I believe FSF does not ship
6337 mips-tfile with gcc version 1, but it will eventually come with gcc
6340 Debugging of g++ output remains a problem. g++ version 1.xx does not
6341 really support it at all. (If you're lucky, you should be able to get
6342 line numbers and stack traces to work, but no parameters or local
6343 variables.) With some work it should be possible to improve the
6346 When gcc version 2 is released, you will have somewhat better luck.
6347 However, even then you will get confusing results for inheritance and
6350 We will eventually provide full debugging of g++ output on
6351 DECstations. This will probably involve some kind of stabs-in-ecoff
6352 encapulation, but the details have not been worked out yet.
6355 *** Changes in GDB-4.2:
6357 * Improved configuration
6359 Only one copy of `configure' exists now, and it is not self-modifying.
6360 Porting BFD is simpler.
6364 The `step' and `next' commands now only stop at the first instruction
6365 of a source line. This prevents the multiple stops that used to occur
6366 in switch statements, for-loops, etc. `Step' continues to stop if a
6367 function that has debugging information is called within the line.
6371 Lots of small bugs fixed. More remain.
6373 * New host supported (not target)
6375 Intel 386 PC clone running Mach i386-none-mach
6378 *** Changes in GDB-4.1:
6380 * Multiple source language support
6382 GDB now has internal scaffolding to handle several source languages.
6383 It determines the type of each source file from its filename extension,
6384 and will switch expression parsing and number formatting to match the
6385 language of the function in the currently selected stack frame.
6386 You can also specifically set the language to be used, with
6387 `set language c' or `set language modula-2'.
6391 GDB now has preliminary support for the GNU Modula-2 compiler,
6392 currently under development at the State University of New York at
6393 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6394 continue through the fall of 1991 and into 1992.
6396 Other Modula-2 compilers are currently not supported, and attempting to
6397 debug programs compiled with them will likely result in an error as the
6398 symbol table is read. Feel free to work on it, though!
6400 There are hooks in GDB for strict type checking and range checking,
6401 in the `Modula-2 philosophy', but they do not currently work.
6405 GDB can now write to executable and core files (e.g. patch
6406 a variable's value). You must turn this switch on, specify
6407 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6408 by assigning a new value to a variable. Modifications take
6411 * Automatic SunOS shared library reading
6413 When you run your program, GDB automatically determines where its
6414 shared libraries (if any) have been loaded, and reads their symbols.
6415 The `share' command is no longer needed. This also works when
6416 examining core files.
6420 You can specify the number of lines that the `list' command shows.
6423 * New machines supported (host and target)
6425 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6426 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6427 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6429 * New hosts supported (not targets)
6431 IBM RT/PC: romp-ibm-aix or rtpc
6433 * New targets supported (not hosts)
6435 AMD 29000 embedded with COFF a29k-none-coff
6436 AMD 29000 embedded with a.out a29k-none-aout
6437 Ultracomputer remote kernel debug a29k-nyu-kern
6439 * New remote interfaces
6445 *** Changes in GDB-4.0:
6449 Wide output is wrapped at good places to make the output more readable.
6451 Gdb now supports cross-debugging from a host machine of one type to a
6452 target machine of another type. Communication with the target system
6453 is over serial lines. The ``target'' command handles connecting to the
6454 remote system; the ``load'' command will download a program into the
6455 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6456 also supports debugging of realtime processes running under VxWorks,
6457 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6458 stub on the target system.
6460 New CPUs supported include the AMD 29000 and Intel 960.
6462 GDB now reads object files and symbol tables via a ``binary file''
6463 library, which allows a single copy of GDB to debug programs of multiple
6464 object file types such as a.out and coff.
6466 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6467 refcard.dvi and refcard.ps are available to format it).
6470 * Control-Variable user interface simplified
6472 All variables that control the operation of the debugger can be set
6473 by the ``set'' command, and displayed by the ``show'' command.
6475 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6476 ``Show prompt'' produces the response:
6477 Gdb's prompt is new-gdb=>.
6479 What follows are the NEW set commands. The command ``help set'' will
6480 print a complete list of old and new set commands. ``help set FOO''
6481 will give a longer description of the variable FOO. ``show'' will show
6482 all of the variable descriptions and their current settings.
6484 confirm on/off: Enables warning questions for operations that are
6485 hard to recover from, e.g. rerunning the program while
6486 it is already running. Default is ON.
6488 editing on/off: Enables EMACS style command line editing
6489 of input. Previous lines can be recalled with
6490 control-P, the current line can be edited with control-B,
6491 you can search for commands with control-R, etc.
6494 history filename NAME: NAME is where the gdb command history
6495 will be stored. The default is .gdb_history,
6496 or the value of the environment variable
6499 history size N: The size, in commands, of the command history. The
6500 default is 256, or the value of the environment variable
6503 history save on/off: If this value is set to ON, the history file will
6504 be saved after exiting gdb. If set to OFF, the
6505 file will not be saved. The default is OFF.
6507 history expansion on/off: If this value is set to ON, then csh-like
6508 history expansion will be performed on
6509 command line input. The default is OFF.
6511 radix N: Sets the default radix for input and output. It can be set
6512 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6513 in the current radix, so "set radix 10" is always a no-op.
6515 height N: This integer value is the number of lines on a page. Default
6516 is 24, the current `stty rows'' setting, or the ``li#''
6517 setting from the termcap entry matching the environment
6520 width N: This integer value is the number of characters on a line.
6521 Default is 80, the current `stty cols'' setting, or the ``co#''
6522 setting from the termcap entry matching the environment
6525 Note: ``set screensize'' is obsolete. Use ``set height'' and
6526 ``set width'' instead.
6528 print address on/off: Print memory addresses in various command displays,
6529 such as stack traces and structure values. Gdb looks
6530 more ``symbolic'' if you turn this off; it looks more
6531 ``machine level'' with it on. Default is ON.
6533 print array on/off: Prettyprint arrays. New convenient format! Default
6536 print demangle on/off: Print C++ symbols in "source" form if on,
6539 print asm-demangle on/off: Same, for assembler level printouts
6542 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6545 * Support for Epoch Environment.
6547 The epoch environment is a version of Emacs v18 with windowing. One
6548 new command, ``inspect'', is identical to ``print'', except that if you
6549 are running in the epoch environment, the value is printed in its own
6553 * Support for Shared Libraries
6555 GDB can now debug programs and core files that use SunOS shared libraries.
6556 Symbols from a shared library cannot be referenced
6557 before the shared library has been linked with the program (this
6558 happens after you type ``run'' and before the function main() is entered).
6559 At any time after this linking (including when examining core files
6560 from dynamically linked programs), gdb reads the symbols from each
6561 shared library when you type the ``sharedlibrary'' command.
6562 It can be abbreviated ``share''.
6564 sharedlibrary REGEXP: Load shared object library symbols for files
6565 matching a unix regular expression. No argument
6566 indicates to load symbols for all shared libraries.
6568 info sharedlibrary: Status of loaded shared libraries.
6573 A watchpoint stops execution of a program whenever the value of an
6574 expression changes. Checking for this slows down execution
6575 tremendously whenever you are in the scope of the expression, but is
6576 quite useful for catching tough ``bit-spreader'' or pointer misuse
6577 problems. Some machines such as the 386 have hardware for doing this
6578 more quickly, and future versions of gdb will use this hardware.
6580 watch EXP: Set a watchpoint (breakpoint) for an expression.
6582 info watchpoints: Information about your watchpoints.
6584 delete N: Deletes watchpoint number N (same as breakpoints).
6585 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6586 enable N: Re-enables watchpoint number N (same as breakpoints).
6589 * C++ multiple inheritance
6591 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6594 * C++ exception handling
6596 Gdb now supports limited C++ exception handling. Besides the existing
6597 ability to breakpoint on an exception handler, gdb can breakpoint on
6598 the raising of an exception (before the stack is peeled back to the
6601 catch FOO: If there is a FOO exception handler in the dynamic scope,
6602 set a breakpoint to catch exceptions which may be raised there.
6603 Multiple exceptions (``catch foo bar baz'') may be caught.
6605 info catch: Lists all exceptions which may be caught in the
6606 current stack frame.
6609 * Minor command changes
6611 The command ``call func (arg, arg, ...)'' now acts like the print
6612 command, except it does not print or save a value if the function's result
6613 is void. This is similar to dbx usage.
6615 The ``up'' and ``down'' commands now always print the frame they end up
6616 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6617 frames without printing.
6619 * New directory command
6621 'dir' now adds directories to the FRONT of the source search path.
6622 The path starts off empty. Source files that contain debug information
6623 about the directory in which they were compiled can be found even
6624 with an empty path; Sun CC and GCC include this information. If GDB can't
6625 find your source file in the current directory, type "dir .".
6627 * Configuring GDB for compilation
6629 For normal use, type ``./configure host''. See README or gdb.texinfo
6632 GDB now handles cross debugging. If you are remotely debugging between
6633 two different machines, type ``./configure host -target=targ''.
6634 Host is the machine where GDB will run; targ is the machine
6635 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob