1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.0
6 * GDB now supports access to the guarded-storage-control registers and the
7 software-based guarded-storage broadcast control registers on IBM z14.
9 * On Unix systems, GDB now supports transmitting environment variables
10 that are to be set or unset to GDBserver. These variables will
11 affect the environment to be passed to the remote inferior.
13 To inform GDB of environment variables that are to be transmitted to
14 GDBserver, use the "set environment" command. Only user set
15 environment variables are sent to GDBserver.
17 To inform GDB of environment variables that are to be unset before
18 the remote inferior is started by the GDBserver, use the "unset
23 ** New events gdb.new_inferior, gdb.inferior_deleted, and
24 gdb.new_thread are emitted. See the manual for further
27 * New features in the GDB remote stub, GDBserver
29 ** GDBserver is now able to start inferior processes with a
30 specified initial working directory.
32 The user can set the desired working directory to be used from
33 GDB using the new "set cwd" command.
35 ** New "--selftest" command line option runs some GDBserver self
36 tests. These self tests are disabled in releases.
38 ** On Unix systems, GDBserver now does globbing expansion and variable
39 substitution in inferior command line arguments.
41 This is done by starting inferiors using a shell, like GDB does.
42 See "set startup-with-shell" in the user manual for how to disable
43 this from GDB when using "target extended-remote". When using
44 "target remote", you can disable the startup with shell by using the
45 new "--no-startup-with-shell" GDBserver command line option.
47 ** On Unix systems, GDBserver now supports receiving environment
48 variables that are to be set or unset from GDB. These variables
49 will affect the environment to be passed to the inferior.
53 QEnvironmentHexEncoded
54 Inform GDBserver of an environment variable that is to be passed to
55 the inferior when starting it.
58 Inform GDBserver of an environment variable that is to be unset
59 before starting the remote inferior.
62 Inform GDBserver that the environment should be reset (i.e.,
63 user-set environment variables should be unset).
66 Indicates whether the inferior must be started with a shell or not.
69 Tell GDBserver that the inferior to be started should use a specific
72 * The "maintenance print c-tdesc" command now takes an optional
73 argument which is the file name of XML target description.
75 * The "maintenance selftest" command now takes an optional argument to
76 filter the tests to be run.
81 Set and show the current working directory for the inferior.
84 Set and show compilation command used for compiling and injecting code
85 with the 'compile' commands.
87 set debug separate-debug-file
88 show debug separate-debug-file
89 Control the display of debug output about separate debug file search.
92 List the registered selftests.
95 Start the debugged program stopping at the first instruction.
97 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
100 * Safer/improved support for debugging with no debug info
102 GDB no longer assumes functions with no debug information return
105 This means that GDB now refuses to call such functions unless you
106 tell it the function's type, by either casting the call to the
107 declared return type, or by casting the function to a function
108 pointer of the right type, and calling that:
110 (gdb) p getenv ("PATH")
111 'getenv' has unknown return type; cast the call to its declared return type
112 (gdb) p (char *) getenv ("PATH")
113 $1 = 0x7fffffffe "/usr/local/bin:/"...
114 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
115 $2 = 0x7fffffffe "/usr/local/bin:/"...
117 Similarly, GDB no longer assumes that global variables with no debug
118 info have type 'int', and refuses to print the variable's value
119 unless you tell it the variable's type:
122 'var' has unknown type; cast it to its declared type
126 * New native configurations
128 FreeBSD/aarch64 aarch64*-*-freebsd*
132 FreeBSD/aarch64 aarch64*-*-freebsd*
133 FreeBSD/arm arm*-*-freebsd*
135 * Removed targets and native configurations
137 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
139 *** Changes in GDB 8.0
141 * GDB now supports access to the PKU register on GNU/Linux. The register is
142 added by the Memory Protection Keys for Userspace feature which will be
143 available in future Intel CPUs.
145 * GDB now supports C++11 rvalue references.
149 ** New functions to start, stop and access a running btrace recording.
150 ** Rvalue references are now supported in gdb.Type.
152 * GDB now supports recording and replaying rdrand and rdseed Intel 64
155 * Building GDB and GDBserver now requires a C++11 compiler.
157 For example, GCC 4.8 or later.
159 It is no longer possible to build GDB or GDBserver with a C
160 compiler. The --disable-build-with-cxx configure option has been
163 * Building GDB and GDBserver now requires GNU make >= 3.81.
165 It is no longer supported to build GDB or GDBserver with another
166 implementation of the make program or an earlier version of GNU make.
168 * Native debugging on MS-Windows supports command-line redirection
170 Command-line arguments used for starting programs on MS-Windows can
171 now include redirection symbols supported by native Windows shells,
172 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
173 as "run", "start", and "set args", as well as the corresponding MI
176 * Support for thread names on MS-Windows.
178 GDB now catches and handles the special exception that programs
179 running on MS-Windows use to assign names to threads in the
182 * Support for Java programs compiled with gcj has been removed.
184 * User commands now accept an unlimited number of arguments.
185 Previously, only up to 10 was accepted.
187 * The "eval" command now expands user-defined command arguments.
189 This makes it easier to process a variable number of arguments:
194 eval "print $arg%d", $i
199 * Target descriptions can now describe registers for sparc32 and sparc64.
201 * GDB now supports DWARF version 5 (debug information format).
202 Its .debug_names index is not yet supported.
204 * New native configurations
206 FreeBSD/mips mips*-*-freebsd
210 Synopsys ARC arc*-*-elf32
211 FreeBSD/mips mips*-*-freebsd
213 * Removed targets and native configurations
215 Alpha running FreeBSD alpha*-*-freebsd*
216 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
221 Erases all the flash memory regions reported by the target.
223 maint print arc arc-instruction address
224 Print internal disassembler information about instruction at a given address.
228 set disassembler-options
229 show disassembler-options
230 Controls the passing of target specific information to the disassembler.
231 If it is necessary to specify more than one disassembler option then
232 multiple options can be placed together into a comma separated list.
233 The default value is the empty string. Currently, the only supported
234 targets are ARM, PowerPC and S/390.
239 Erases all the flash memory regions reported by the target. This is
240 equivalent to the CLI command flash-erase.
242 -file-list-shared-libraries
243 List the shared libraries in the program. This is
244 equivalent to the CLI command "info shared".
246 *** Changes in GDB 7.12
248 * GDB and GDBserver now build with a C++ compiler by default.
250 The --enable-build-with-cxx configure option is now enabled by
251 default. One must now explicitly configure with
252 --disable-build-with-cxx in order to build with a C compiler. This
253 option will be removed in a future release.
255 * GDBserver now supports recording btrace without maintaining an active
258 * GDB now supports a negative repeat count in the 'x' command to examine
259 memory backward from the given address. For example:
262 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
263 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
264 (gdb) x/-5i 0x0000000000400580
265 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
266 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
267 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
268 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
269 0x40057b <main(int, char**)+25>:
270 callq 0x400536 <Func1(int, char const*)>
272 * Fortran: Support structures with fields of dynamic types and
273 arrays of dynamic types.
275 * The symbol dumping maintenance commands have new syntax.
276 maint print symbols [-pc address] [--] [filename]
277 maint print symbols [-objfile objfile] [-source source] [--] [filename]
278 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
279 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
280 maint print msymbols [-objfile objfile] [--] [filename]
282 * GDB now supports multibit bitfields and enums in target register
285 * New Python-based convenience function $_as_string(val), which returns
286 the textual representation of a value. This function is especially
287 useful to obtain the text label of an enum value.
289 * Intel MPX bound violation handling.
291 Segmentation faults caused by a Intel MPX boundary violation
292 now display the kind of violation (upper or lower), the memory
293 address accessed and the memory bounds, along with the usual
294 signal received and code location.
298 Program received signal SIGSEGV, Segmentation fault
299 Upper bound violation while accessing address 0x7fffffffc3b3
300 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
301 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
303 * Rust language support.
304 GDB now supports debugging programs written in the Rust programming
305 language. See https://www.rust-lang.org/ for more information about
308 * Support for running interpreters on specified input/output devices
310 GDB now supports a new mechanism that allows frontends to provide
311 fully featured GDB console views, as a better alternative to
312 building such views on top of the "-interpreter-exec console"
313 command. See the new "new-ui" command below. With that command,
314 frontends can now start GDB in the traditional command-line mode
315 running in an embedded terminal emulator widget, and create a
316 separate MI interpreter running on a specified i/o device. In this
317 way, GDB handles line editing, history, tab completion, etc. in the
318 console all by itself, and the GUI uses the separate MI interpreter
319 for its own control and synchronization, invisible to the command
322 * The "catch syscall" command catches groups of related syscalls.
324 The "catch syscall" command now supports catching a group of related
325 syscalls using the 'group:' or 'g:' prefix.
330 skip -gfile file-glob-pattern
331 skip -function function
332 skip -rfunction regular-expression
333 A generalized form of the skip command, with new support for
334 glob-style file names and regular expressions for function names.
335 Additionally, a file spec and a function spec may now be combined.
337 maint info line-table REGEXP
338 Display the contents of GDB's internal line table data struture.
341 Run any GDB unit tests that were compiled in.
344 Start a new user interface instance running INTERP as interpreter,
345 using the TTY file for input/output.
349 ** gdb.Breakpoint objects have a new attribute "pending", which
350 indicates whether the breakpoint is pending.
351 ** Three new breakpoint-related events have been added:
352 gdb.breakpoint_created, gdb.breakpoint_modified, and
353 gdb.breakpoint_deleted.
356 Signal ("set") the given MS-Windows event object. This is used in
357 conjunction with the Windows JIT debugging (AeDebug) support, where
358 the OS suspends a crashing process until a debugger can attach to
359 it. Resuming the crashing process, in order to debug it, is done by
362 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
363 was added in GDBserver, including JIT compiling fast tracepoint's
364 conditional expression bytecode into native code.
366 * Support for various remote target protocols and ROM monitors has
369 target m32rsdi Remote M32R debugging over SDI
370 target mips MIPS remote debugging protocol
371 target pmon PMON ROM monitor
372 target ddb NEC's DDB variant of PMON for Vr4300
373 target rockhopper NEC RockHopper variant of PMON
374 target lsi LSI variant of PMO
376 * Support for tracepoints and fast tracepoints on powerpc-linux,
377 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
378 including JIT compiling fast tracepoint's conditional expression
379 bytecode into native code.
381 * MI async record =record-started now includes the method and format used for
382 recording. For example:
384 =record-started,thread-group="i1",method="btrace",format="bts"
386 * MI async record =thread-selected now includes the frame field. For example:
388 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
392 Andes NDS32 nds32*-*-elf
394 *** Changes in GDB 7.11
396 * GDB now supports debugging kernel-based threads on FreeBSD.
398 * Per-inferior thread numbers
400 Thread numbers are now per inferior instead of global. If you're
401 debugging multiple inferiors, GDB displays thread IDs using a
402 qualified INF_NUM.THR_NUM form. For example:
406 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
407 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
408 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
409 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
411 As consequence, thread numbers as visible in the $_thread
412 convenience variable and in Python's InferiorThread.num attribute
413 are no longer unique between inferiors.
415 GDB now maintains a second thread ID per thread, referred to as the
416 global thread ID, which is the new equivalent of thread numbers in
417 previous releases. See also $_gthread below.
419 For backwards compatibility, MI's thread IDs always refer to global
422 * Commands that accept thread IDs now accept the qualified
423 INF_NUM.THR_NUM form as well. For example:
426 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
429 * In commands that accept a list of thread IDs, you can now refer to
430 all threads of an inferior using a star wildcard. GDB accepts
431 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
432 refer to all threads of the current inferior. For example, "info
435 * You can use "info threads -gid" to display the global thread ID of
438 * The new convenience variable $_gthread holds the global number of
441 * The new convenience variable $_inferior holds the number of the
444 * GDB now displays the ID and name of the thread that hit a breakpoint
445 or received a signal, if your program is multi-threaded. For
448 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
449 Thread 1 "main" received signal SIGINT, Interrupt.
451 * Record btrace now supports non-stop mode.
453 * Support for tracepoints on aarch64-linux was added in GDBserver.
455 * The 'record instruction-history' command now indicates speculative execution
456 when using the Intel Processor Trace recording format.
458 * GDB now allows users to specify explicit locations, bypassing
459 the linespec parser. This feature is also available to GDB/MI
462 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
463 GDB now is able to debug both AArch64 applications and ARM applications
466 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
467 including JIT compiling fast tracepoint's conditional expression bytecode
470 * GDB now supports displaced stepping on AArch64 GNU/Linux.
472 * "info threads", "info inferiors", "info display", "info checkpoints"
473 and "maint info program-spaces" now list the corresponding items in
474 ascending ID order, for consistency with all other "info" commands.
476 * In Ada, the overloads selection menu has been enhanced to display the
477 parameter types and the return types for the matching overloaded subprograms.
481 maint set target-non-stop (on|off|auto)
482 maint show target-non-stop
483 Control whether GDB targets always operate in non-stop mode even if
484 "set non-stop" is "off". The default is "auto", meaning non-stop
485 mode is enabled if supported by the target.
487 maint set bfd-sharing
488 maint show bfd-sharing
489 Control the reuse of bfd objects.
493 Control display of debugging info regarding bfd caching.
497 Control display of debugging info regarding FreeBSD threads.
499 set remote multiprocess-extensions-packet
500 show remote multiprocess-extensions-packet
501 Set/show the use of the remote protocol multiprocess extensions.
503 set remote thread-events
504 show remote thread-events
505 Set/show the use of thread create/exit events.
507 set ada print-signatures on|off
508 show ada print-signatures"
509 Control whether parameter types and return types are displayed in overloads
510 selection menus. It is activaled (@code{on}) by default.
514 Controls the maximum size of memory, in bytes, that GDB will
515 allocate for value contents. Prevents incorrect programs from
516 causing GDB to allocate overly large buffers. Default is 64k.
518 * The "disassemble" command accepts a new modifier: /s.
519 It prints mixed source+disassembly like /m with two differences:
520 - disassembled instructions are now printed in program order, and
521 - and source for all relevant files is now printed.
522 The "/m" option is now considered deprecated: its "source-centric"
523 output hasn't proved useful in practice.
525 * The "record instruction-history" command accepts a new modifier: /s.
526 It behaves exactly like /m and prints mixed source+disassembly.
528 * The "set scheduler-locking" command supports a new mode "replay".
529 It behaves like "off" in record mode and like "on" in replay mode.
531 * Support for various ROM monitors has been removed:
533 target dbug dBUG ROM monitor for Motorola ColdFire
534 target picobug Motorola picobug monitor
535 target dink32 DINK32 ROM monitor for PowerPC
536 target m32r Renesas M32R/D ROM monitor
537 target mon2000 mon2000 ROM monitor
538 target ppcbug PPCBUG ROM monitor for PowerPC
540 * Support for reading/writing memory and extracting values on architectures
541 whose memory is addressable in units of any integral multiple of 8 bits.
546 Indicates that an exec system call was executed.
548 exec-events feature in qSupported
549 The qSupported packet allows GDB to request support for exec
550 events using the new 'gdbfeature' exec-event, and the qSupported
551 response can contain the corresponding 'stubfeature'. Set and
552 show commands can be used to display whether these features are enabled.
555 Equivalent to interrupting with the ^C character, but works in
558 thread created stop reason (T05 create:...)
559 Indicates that the thread was just created and is stopped at entry.
561 thread exit stop reply (w exitcode;tid)
562 Indicates that the thread has terminated.
565 Enables/disables thread create and exit event reporting. For
566 example, this is used in non-stop mode when GDB stops a set of
567 threads and synchronously waits for the their corresponding stop
568 replies. Without exit events, if one of the threads exits, GDB
569 would hang forever not knowing that it should no longer expect a
570 stop for that same thread.
573 Indicates that there are no resumed threads left in the target (all
574 threads are stopped). The remote stub reports support for this stop
575 reply to GDB's qSupported query.
578 Enables/disables catching syscalls from the inferior process.
579 The remote stub reports support for this packet to GDB's qSupported query.
581 syscall_entry stop reason
582 Indicates that a syscall was just called.
584 syscall_return stop reason
585 Indicates that a syscall just returned.
587 * Extended-remote exec events
589 ** GDB now has support for exec events on extended-remote Linux targets.
590 For such targets with Linux kernels 2.5.46 and later, this enables
591 follow-exec-mode and exec catchpoints.
593 set remote exec-event-feature-packet
594 show remote exec-event-feature-packet
595 Set/show the use of the remote exec event feature.
597 * Thread names in remote protocol
599 The reply to qXfer:threads:read may now include a name attribute for each
602 * Target remote mode fork and exec events
604 ** GDB now has support for fork and exec events on target remote mode
605 Linux targets. For such targets with Linux kernels 2.5.46 and later,
606 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
607 fork and exec catchpoints.
609 * Remote syscall events
611 ** GDB now has support for catch syscall on remote Linux targets,
612 currently enabled on x86/x86_64 architectures.
614 set remote catch-syscall-packet
615 show remote catch-syscall-packet
616 Set/show the use of the remote catch syscall feature.
620 ** The -var-set-format command now accepts the zero-hexadecimal
621 format. It outputs data in hexadecimal format with zero-padding on the
626 ** gdb.InferiorThread objects have a new attribute "global_num",
627 which refers to the thread's global thread ID. The existing
628 "num" attribute now refers to the thread's per-inferior number.
629 See "Per-inferior thread numbers" above.
630 ** gdb.InferiorThread objects have a new attribute "inferior", which
631 is the Inferior object the thread belongs to.
633 *** Changes in GDB 7.10
635 * Support for process record-replay and reverse debugging on aarch64*-linux*
636 targets has been added. GDB now supports recording of A64 instruction set
637 including advance SIMD instructions.
639 * Support for Sun's version of the "stabs" debug file format has been removed.
641 * GDB now honors the content of the file /proc/PID/coredump_filter
642 (PID is the process ID) on GNU/Linux systems. This file can be used
643 to specify the types of memory mappings that will be included in a
644 corefile. For more information, please refer to the manual page of
645 "core(5)". GDB also has a new command: "set use-coredump-filter
646 on|off". It allows to set whether GDB will read the content of the
647 /proc/PID/coredump_filter file when generating a corefile.
649 * The "info os" command on GNU/Linux can now display information on
651 "info os cpus" Listing of all cpus/cores on the system
653 * GDB has two new commands: "set serial parity odd|even|none" and
654 "show serial parity". These allows to set or show parity for the
657 * The "info source" command now displays the producer string if it was
658 present in the debug info. This typically includes the compiler version
659 and may include things like its command line arguments.
661 * The "info dll", an alias of the "info sharedlibrary" command,
662 is now available on all platforms.
664 * Directory names supplied to the "set sysroot" commands may be
665 prefixed with "target:" to tell GDB to access shared libraries from
666 the target system, be it local or remote. This replaces the prefix
667 "remote:". The default sysroot has been changed from "" to
668 "target:". "remote:" is automatically converted to "target:" for
669 backward compatibility.
671 * The system root specified by "set sysroot" will be prepended to the
672 filename of the main executable (if reported to GDB as absolute by
673 the operating system) when starting processes remotely, and when
674 attaching to already-running local or remote processes.
676 * GDB now supports automatic location and retrieval of executable
677 files from remote targets. Remote debugging can now be initiated
678 using only a "target remote" or "target extended-remote" command
679 (no "set sysroot" or "file" commands are required). See "New remote
682 * The "dump" command now supports verilog hex format.
684 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
686 * On GNU/Linux, GDB and gdbserver are now able to access executable
687 and shared library files without a "set sysroot" command when
688 attaching to processes running in different mount namespaces from
689 the debugger. This makes it possible to attach to processes in
690 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
691 See "New remote packets" below.
693 * The "tui reg" command now provides completion for all of the
694 available register groups, including target specific groups.
696 * The HISTSIZE environment variable is no longer read when determining
697 the size of GDB's command history. GDB now instead reads the dedicated
698 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
699 disables truncation of command history. Non-numeric values of GDBHISTSIZE
704 ** Memory ports can now be unbuffered.
708 ** gdb.Objfile objects have a new attribute "username",
709 which is the name of the objfile as specified by the user,
710 without, for example, resolving symlinks.
711 ** You can now write frame unwinders in Python.
712 ** gdb.Type objects have a new method "optimized_out",
713 returning optimized out gdb.Value instance of this type.
714 ** gdb.Value objects have new methods "reference_value" and
715 "const_value" which return a reference to the value and a
716 "const" version of the value respectively.
720 maint print symbol-cache
721 Print the contents of the symbol cache.
723 maint print symbol-cache-statistics
724 Print statistics of symbol cache usage.
726 maint flush-symbol-cache
727 Flush the contents of the symbol cache.
731 Start branch trace recording using Branch Trace Store (BTS) format.
734 Evaluate expression by using the compiler and print result.
738 Explicit commands for enabling and disabling tui mode.
741 set mpx bound on i386 and amd64
742 Support for bound table investigation on Intel MPX enabled applications.
746 Start branch trace recording using Intel Processor Trace format.
749 Print information about branch tracing internals.
751 maint btrace packet-history
752 Print the raw branch tracing data.
754 maint btrace clear-packet-history
755 Discard the stored raw branch tracing data.
758 Discard all branch tracing data. It will be fetched and processed
759 anew by the next "record" command.
764 Renamed from "set debug dwarf2-die".
766 Renamed from "show debug dwarf2-die".
769 Renamed from "set debug dwarf2-read".
770 show debug dwarf-read
771 Renamed from "show debug dwarf2-read".
773 maint set dwarf always-disassemble
774 Renamed from "maint set dwarf2 always-disassemble".
775 maint show dwarf always-disassemble
776 Renamed from "maint show dwarf2 always-disassemble".
778 maint set dwarf max-cache-age
779 Renamed from "maint set dwarf2 max-cache-age".
780 maint show dwarf max-cache-age
781 Renamed from "maint show dwarf2 max-cache-age".
784 show debug dwarf-line
785 Control display of debugging info regarding DWARF line processing.
789 Set the maximum number of candidates to be considered during
790 completion. The default value is 200. This limit allows GDB
791 to avoid generating large completion lists, the computation of
792 which can cause the debugger to become temporarily unresponsive.
794 set history remove-duplicates
795 show history remove-duplicates
796 Control the removal of duplicate history entries.
798 maint set symbol-cache-size
799 maint show symbol-cache-size
800 Control the size of the symbol cache.
802 set|show record btrace bts buffer-size
803 Set and show the size of the ring buffer used for branch tracing in
805 The obtained size may differ from the requested size. Use "info
806 record" to see the obtained buffer size.
808 set debug linux-namespaces
809 show debug linux-namespaces
810 Control display of debugging info regarding Linux namespaces.
812 set|show record btrace pt buffer-size
813 Set and show the size of the ring buffer used for branch tracing in
814 Intel Processor Trace format.
815 The obtained size may differ from the requested size. Use "info
816 record" to see the obtained buffer size.
818 maint set|show btrace pt skip-pad
819 Set and show whether PAD packets are skipped when computing the
822 * The command 'thread apply all' can now support new option '-ascending'
823 to call its specified command for all threads in ascending order.
825 * Python/Guile scripting
827 ** GDB now supports auto-loading of Python/Guile scripts contained in the
828 special section named `.debug_gdb_scripts'.
832 qXfer:btrace-conf:read
833 Return the branch trace configuration for the current thread.
835 Qbtrace-conf:bts:size
836 Set the requested ring buffer size for branch tracing in BTS format.
839 Enable Intel Procesor Trace-based branch tracing for the current
840 process. The remote stub reports support for this packet to GDB's
844 Set the requested ring buffer size for branch tracing in Intel Processor
848 Indicates a memory breakpoint instruction was executed, irrespective
849 of whether it was GDB that planted the breakpoint or the breakpoint
850 is hardcoded in the program. This is required for correct non-stop
854 Indicates the target stopped for a hardware breakpoint. This is
855 required for correct non-stop mode operation.
858 Return information about files on the remote system.
861 Return the full absolute name of the file that was executed to
862 create a process running on the remote system.
865 Select the filesystem on which vFile: operations with filename
866 arguments will operate. This is required for GDB to be able to
867 access files on remote targets where the remote stub does not
868 share a common filesystem with the inferior(s).
871 Indicates that a fork system call was executed.
874 Indicates that a vfork system call was executed.
876 vforkdone stop reason
877 Indicates that a vfork child of the specified process has executed
878 an exec or exit, allowing the vfork parent to resume execution.
880 fork-events and vfork-events features in qSupported
881 The qSupported packet allows GDB to request support for fork and
882 vfork events using new 'gdbfeatures' fork-events and vfork-events,
883 and the qSupported response can contain the corresponding
884 'stubfeatures'. Set and show commands can be used to display
885 whether these features are enabled.
887 * Extended-remote fork events
889 ** GDB now has support for fork events on extended-remote Linux
890 targets. For targets with Linux kernels 2.5.60 and later, this
891 enables follow-fork-mode and detach-on-fork for both fork and
892 vfork, as well as fork and vfork catchpoints.
894 * The info record command now shows the recording format and the
895 branch tracing configuration for the current thread when using
896 the btrace record target.
897 For the BTS format, it shows the ring buffer size.
899 * GDB now has support for DTrace USDT (Userland Static Defined
900 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
902 * GDB now supports access to vector registers on S/390 GNU/Linux
905 * Removed command line options
907 -xdb HP-UX XDB compatibility mode.
909 * Removed targets and native configurations
911 HP/PA running HP-UX hppa*-*-hpux*
912 Itanium running HP-UX ia64-*-hpux*
914 * New configure options
917 This configure option allows the user to build GDB with support for
918 Intel Processor Trace (default: auto). This requires libipt.
920 --with-libipt-prefix=PATH
921 Specify the path to the version of libipt that GDB should use.
922 $PATH/include should contain the intel-pt.h header and
923 $PATH/lib should contain the libipt.so library.
925 *** Changes in GDB 7.9.1
929 ** Xmethods can now specify a result type.
931 *** Changes in GDB 7.9
933 * GDB now supports hardware watchpoints on x86 GNU Hurd.
937 ** You can now access frame registers from Python scripts.
938 ** New attribute 'producer' for gdb.Symtab objects.
939 ** gdb.Objfile objects have a new attribute "progspace",
940 which is the gdb.Progspace object of the containing program space.
941 ** gdb.Objfile objects have a new attribute "owner".
942 ** gdb.Objfile objects have a new attribute "build_id",
943 which is the build ID generated when the file was built.
944 ** gdb.Objfile objects have a new method "add_separate_debug_file".
945 ** A new event "gdb.clear_objfiles" has been added, triggered when
946 selecting a new file to debug.
947 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
948 ** New function gdb.lookup_objfile.
950 New events which are triggered when GDB modifies the state of the
953 ** gdb.events.inferior_call_pre: Function call is about to be made.
954 ** gdb.events.inferior_call_post: Function call has just been made.
955 ** gdb.events.memory_changed: A memory location has been altered.
956 ** gdb.events.register_changed: A register has been altered.
958 * New Python-based convenience functions:
960 ** $_caller_is(name [, number_of_frames])
961 ** $_caller_matches(regexp [, number_of_frames])
962 ** $_any_caller_is(name [, number_of_frames])
963 ** $_any_caller_matches(regexp [, number_of_frames])
965 * GDB now supports the compilation and injection of source code into
966 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
967 to compile the source code to object code, and if successful, inject
968 and execute that code within the current context of the inferior.
969 Currently the C language is supported. The commands used to
970 interface with this new feature are:
972 compile code [-raw|-r] [--] [source code]
973 compile file [-raw|-r] filename
977 demangle [-l language] [--] name
978 Demangle "name" in the specified language, or the current language
979 if elided. This command is renamed from the "maint demangle" command.
980 The latter is kept as a no-op to avoid "maint demangle" being interpreted
981 as "maint demangler-warning".
983 queue-signal signal-name-or-number
984 Queue a signal to be delivered to the thread when it is resumed.
986 add-auto-load-scripts-directory directory
987 Add entries to the list of directories from which to load auto-loaded
990 maint print user-registers
991 List all currently available "user" registers.
993 compile code [-r|-raw] [--] [source code]
994 Compile, inject, and execute in the inferior the executable object
995 code produced by compiling the provided source code.
997 compile file [-r|-raw] filename
998 Compile and inject into the inferior the executable object code
999 produced by compiling the source code stored in the filename
1002 * On resume, GDB now always passes the signal the program had stopped
1003 for to the thread the signal was sent to, even if the user changed
1004 threads before resuming. Previously GDB would often (but not
1005 always) deliver the signal to the thread that happens to be current
1008 * Conversely, the "signal" command now consistently delivers the
1009 requested signal to the current thread. GDB now asks for
1010 confirmation if the program had stopped for a signal and the user
1011 switched threads meanwhile.
1013 * "breakpoint always-inserted" modes "off" and "auto" merged.
1015 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1016 won't remove breakpoints from the target until all threads stop,
1017 even in non-stop mode. The "auto" mode has been removed, and "off"
1018 is now the default mode.
1022 set debug symbol-lookup
1023 show debug symbol-lookup
1024 Control display of debugging info regarding symbol lookup.
1028 ** The -list-thread-groups command outputs an exit-code field for
1029 inferiors that have exited.
1033 MIPS SDE mips*-sde*-elf*
1037 Support for these obsolete configurations has been removed.
1039 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1040 SGI Irix-5.x mips-*-irix5*
1041 SGI Irix-6.x mips-*-irix6*
1042 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1043 VAX running Ultrix vax-*-ultrix*
1045 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1046 and "assf"), have been removed. Use the "sharedlibrary" command, or
1047 its alias "share", instead.
1049 *** Changes in GDB 7.8
1051 * New command line options
1054 This is an alias for the --data-directory option.
1056 * GDB supports printing and modifying of variable length automatic arrays
1057 as specified in ISO C99.
1059 * The ARM simulator now supports instruction level tracing
1060 with or without disassembly.
1064 GDB now has support for scripting using Guile. Whether this is
1065 available is determined at configure time.
1066 Guile version 2.0 or greater is required.
1067 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1069 * New commands (for set/show, see "New options" below)
1073 Invoke CODE by passing it to the Guile interpreter.
1077 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1079 info auto-load guile-scripts [regexp]
1080 Print the list of automatically loaded Guile scripts.
1082 * The source command is now capable of sourcing Guile scripts.
1083 This feature is dependent on the debugger being built with Guile support.
1087 set print symbol-loading (off|brief|full)
1088 show print symbol-loading
1089 Control whether to print informational messages when loading symbol
1090 information for a file. The default is "full", but when debugging
1091 programs with large numbers of shared libraries the amount of output
1092 becomes less useful.
1094 set guile print-stack (none|message|full)
1095 show guile print-stack
1096 Show a stack trace when an error is encountered in a Guile script.
1098 set auto-load guile-scripts (on|off)
1099 show auto-load guile-scripts
1100 Control auto-loading of Guile script files.
1102 maint ada set ignore-descriptive-types (on|off)
1103 maint ada show ignore-descriptive-types
1104 Control whether the debugger should ignore descriptive types in Ada
1105 programs. The default is not to ignore the descriptive types. See
1106 the user manual for more details on descriptive types and the intended
1107 usage of this option.
1109 set auto-connect-native-target
1111 Control whether GDB is allowed to automatically connect to the
1112 native target for the run, attach, etc. commands when not connected
1113 to any target yet. See also "target native" below.
1115 set record btrace replay-memory-access (read-only|read-write)
1116 show record btrace replay-memory-access
1117 Control what memory accesses are allowed during replay.
1119 maint set target-async (on|off)
1120 maint show target-async
1121 This controls whether GDB targets operate in synchronous or
1122 asynchronous mode. Normally the default is asynchronous, if it is
1123 available; but this can be changed to more easily debug problems
1124 occurring only in synchronous mode.
1126 set mi-async (on|off)
1128 Control whether MI asynchronous mode is preferred. This supersedes
1129 "set target-async" of previous GDB versions.
1131 * "set target-async" is deprecated as a CLI option and is now an alias
1132 for "set mi-async" (only puts MI into async mode).
1134 * Background execution commands (e.g., "c&", "s&", etc.) are now
1135 possible ``out of the box'' if the target supports them. Previously
1136 the user would need to explicitly enable the possibility with the
1137 "set target-async on" command.
1139 * New features in the GDB remote stub, GDBserver
1141 ** New option --debug-format=option1[,option2,...] allows one to add
1142 additional text to each output. At present only timestamps
1143 are supported: --debug-format=timestamps.
1144 Timestamps can also be turned on with the
1145 "monitor set debug-format timestamps" command from GDB.
1147 * The 'record instruction-history' command now starts counting instructions
1148 at one. This also affects the instruction ranges reported by the
1149 'record function-call-history' command when given the /i modifier.
1151 * The command 'record function-call-history' supports a new modifier '/c' to
1152 indent the function names based on their call stack depth.
1153 The fields for the '/i' and '/l' modifier have been reordered.
1154 The source line range is now prefixed with 'at'.
1155 The instruction range is now prefixed with 'inst'.
1156 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1157 "record instruction-history" and "list" commands.
1159 * The ranges given as arguments to the 'record function-call-history' and
1160 'record instruction-history' commands are now inclusive.
1162 * The btrace record target now supports the 'record goto' command.
1163 For locations inside the execution trace, the back trace is computed
1164 based on the information stored in the execution trace.
1166 * The btrace record target supports limited reverse execution and replay.
1167 The target does not record data and therefore does not allow reading
1168 memory or registers.
1170 * The "catch syscall" command now works on s390*-linux* targets.
1172 * The "compare-sections" command is no longer specific to target
1173 remote. It now works with all targets.
1175 * All native targets are now consistently called "native".
1176 Consequently, the "target child", "target GNU", "target djgpp",
1177 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1178 commands have been replaced with "target native". The QNX/NTO port
1179 leaves the "procfs" target in place and adds a "native" target for
1180 consistency with other ports. The impact on users should be minimal
1181 as these commands previously either throwed an error, or were
1182 no-ops. The target's name is visible in the output of the following
1183 commands: "help target", "info target", "info files", "maint print
1186 * The "target native" command now connects to the native target. This
1187 can be used to launch native programs even when "set
1188 auto-connect-native-target" is set to off.
1190 * GDB now supports access to Intel MPX registers on GNU/Linux.
1192 * Support for Intel AVX-512 registers on GNU/Linux.
1193 Support displaying and modifying Intel AVX-512 registers
1194 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1196 * New remote packets
1198 qXfer:btrace:read's annex
1199 The qXfer:btrace:read packet supports a new annex 'delta' to read
1200 branch trace incrementally.
1204 ** Valid Python operations on gdb.Value objects representing
1205 structs/classes invoke the corresponding overloaded operators if
1207 ** New `Xmethods' feature in the Python API. Xmethods are
1208 additional methods or replacements for existing methods of a C++
1209 class. This feature is useful for those cases where a method
1210 defined in C++ source code could be inlined or optimized out by
1211 the compiler, making it unavailable to GDB.
1214 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1216 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1217 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1218 its alias "share", instead.
1220 * The commands "set remotebaud" and "show remotebaud" are no longer
1221 supported. Use "set serial baud" and "show serial baud" (respectively)
1226 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1227 target-async". The latter is left as a deprecated alias of the
1228 former for backward compatibility. If the target supports it,
1229 CLI background execution commands are now always possible by
1230 default, independently of whether the frontend stated a
1231 preference for asynchronous execution with "-gdb-set mi-async".
1232 Previously "-gdb-set target-async off" affected both MI execution
1233 commands and CLI execution commands.
1235 *** Changes in GDB 7.7
1237 * Improved support for process record-replay and reverse debugging on
1238 arm*-linux* targets. Support for thumb32 and syscall instruction
1239 recording has been added.
1241 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1243 * GDB now supports Fission DWP file format version 2.
1244 http://gcc.gnu.org/wiki/DebugFission
1246 * New convenience function "$_isvoid", to check whether an expression
1247 is void. A void expression is an expression where the type of the
1248 result is "void". For example, some convenience variables may be
1249 "void" when evaluated (e.g., "$_exitcode" before the execution of
1250 the program being debugged; or an undefined convenience variable).
1251 Another example, when calling a function whose return type is
1254 * The "maintenance print objfiles" command now takes an optional regexp.
1256 * The "catch syscall" command now works on arm*-linux* targets.
1258 * GDB now consistently shows "<not saved>" when printing values of
1259 registers the debug info indicates have not been saved in the frame
1260 and there's nowhere to retrieve them from
1261 (callee-saved/call-clobbered registers):
1266 (gdb) info registers rax
1269 Before, the former would print "<optimized out>", and the latter
1270 "*value not available*".
1272 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1277 ** Frame filters and frame decorators have been added.
1278 ** Temporary breakpoints are now supported.
1279 ** Line tables representation has been added.
1280 ** New attribute 'parent_type' for gdb.Field objects.
1281 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1282 ** New attribute 'name' for gdb.Type objects.
1286 Nios II ELF nios2*-*-elf
1287 Nios II GNU/Linux nios2*-*-linux
1288 Texas Instruments MSP430 msp430*-*-elf
1290 * Removed native configurations
1292 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1293 been removed. ELF variants of these configurations are kept supported.
1295 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1296 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1297 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1298 i[34567]86-*-openbsd3.[0-3]
1299 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1300 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1301 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1305 Like "catch throw", but catches a re-thrown exception.
1306 maint check-psymtabs
1307 Renamed from old "maint check-symtabs".
1309 Perform consistency checks on symtabs.
1310 maint expand-symtabs
1311 Expand symtabs matching an optional regexp.
1314 Display the details of GDB configure-time options.
1316 maint set|show per-command
1317 maint set|show per-command space
1318 maint set|show per-command time
1319 maint set|show per-command symtab
1320 Enable display of per-command gdb resource usage.
1322 remove-symbol-file FILENAME
1323 remove-symbol-file -a ADDRESS
1324 Remove a symbol file added via add-symbol-file. The file to remove
1325 can be identified by its filename or by an address that lies within
1326 the boundaries of this symbol file in memory.
1329 info exceptions REGEXP
1330 Display the list of Ada exceptions defined in the program being
1331 debugged. If provided, only the exceptions whose names match REGEXP
1336 set debug symfile off|on
1338 Control display of debugging info regarding reading symbol files and
1339 symbol tables within those files
1341 set print raw frame-arguments
1342 show print raw frame-arguments
1343 Set/show whether to print frame arguments in raw mode,
1344 disregarding any defined pretty-printers.
1346 set remote trace-status-packet
1347 show remote trace-status-packet
1348 Set/show the use of remote protocol qTStatus packet.
1352 Control display of debugging messages related to Nios II targets.
1356 Control whether target-assisted range stepping is enabled.
1358 set startup-with-shell
1359 show startup-with-shell
1360 Specifies whether Unix child processes are started via a shell or
1365 Use the target memory cache for accesses to the code segment. This
1366 improves performance of remote debugging (particularly disassembly).
1368 * You can now use a literal value 'unlimited' for options that
1369 interpret 0 or -1 as meaning "unlimited". E.g., "set
1370 trace-buffer-size unlimited" is now an alias for "set
1371 trace-buffer-size -1" and "set height unlimited" is now an alias for
1374 * The "set debug symtab-create" debugging option of GDB has been changed to
1375 accept a verbosity level. 0 means "off", 1 provides basic debugging
1376 output, and values of 2 or greater provides more verbose output.
1378 * New command-line options
1380 Display the details of GDB configure-time options.
1382 * The command 'tsave' can now support new option '-ctf' to save trace
1383 buffer in Common Trace Format.
1385 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1388 * GDB now implements the the C++ 'typeid' operator.
1390 * The new convenience variable $_exception holds the exception being
1391 thrown or caught at an exception-related catchpoint.
1393 * The exception-related catchpoints, like "catch throw", now accept a
1394 regular expression which can be used to filter exceptions by type.
1396 * The new convenience variable $_exitsignal is automatically set to
1397 the terminating signal number when the program being debugged dies
1398 due to an uncaught signal.
1402 ** All MI commands now accept an optional "--language" option.
1403 Support for this feature can be verified by using the "-list-features"
1404 command, which should contain "language-option".
1406 ** The new command -info-gdb-mi-command allows the user to determine
1407 whether a GDB/MI command is supported or not.
1409 ** The "^error" result record returned when trying to execute an undefined
1410 GDB/MI command now provides a variable named "code" whose content is the
1411 "undefined-command" error code. Support for this feature can be verified
1412 by using the "-list-features" command, which should contain
1413 "undefined-command-error-code".
1415 ** The -trace-save MI command can optionally save trace buffer in Common
1418 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1420 ** The command -data-list-register-values now accepts an optional
1421 "--skip-unavailable" option. When used, only the available registers
1424 ** The new command -trace-frame-collected dumps collected variables,
1425 computed expressions, tvars, memory and registers in a traceframe.
1427 ** The commands -stack-list-locals, -stack-list-arguments and
1428 -stack-list-variables now accept an option "--skip-unavailable".
1429 When used, only the available locals or arguments are displayed.
1431 ** The -exec-run command now accepts an optional "--start" option.
1432 When used, the command follows the same semantics as the "start"
1433 command, stopping the program's execution at the start of its
1434 main subprogram. Support for this feature can be verified using
1435 the "-list-features" command, which should contain
1436 "exec-run-start-option".
1438 ** The new commands -catch-assert and -catch-exceptions insert
1439 catchpoints stopping the program when Ada exceptions are raised.
1441 ** The new command -info-ada-exceptions provides the equivalent of
1442 the new "info exceptions" command.
1444 * New system-wide configuration scripts
1445 A GDB installation now provides scripts suitable for use as system-wide
1446 configuration scripts for the following systems:
1450 * GDB now supports target-assigned range stepping with remote targets.
1451 This improves the performance of stepping source lines by reducing
1452 the number of control packets from/to GDB. See "New remote packets"
1455 * GDB now understands the element 'tvar' in the XML traceframe info.
1456 It has the id of the collected trace state variables.
1458 * On S/390 targets that provide the transactional-execution feature,
1459 the program interruption transaction diagnostic block (TDB) is now
1460 represented as a number of additional "registers" in GDB.
1462 * New remote packets
1466 The vCont packet supports a new 'r' action, that tells the remote
1467 stub to step through an address range itself, without GDB
1468 involvemement at each single-step.
1470 qXfer:libraries-svr4:read's annex
1471 The previously unused annex of the qXfer:libraries-svr4:read packet
1472 is now used to support passing an argument list. The remote stub
1473 reports support for this argument list to GDB's qSupported query.
1474 The defined arguments are "start" and "prev", used to reduce work
1475 necessary for library list updating, resulting in significant
1478 * New features in the GDB remote stub, GDBserver
1480 ** GDBserver now supports target-assisted range stepping. Currently
1481 enabled on x86/x86_64 GNU/Linux targets.
1483 ** GDBserver now adds element 'tvar' in the XML in the reply to
1484 'qXfer:traceframe-info:read'. It has the id of the collected
1485 trace state variables.
1487 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1490 * New 'z' formatter for printing and examining memory, this displays the
1491 value as hexadecimal zero padded on the left to the size of the type.
1493 * GDB can now use Windows x64 unwinding data.
1495 * The "set remotebaud" command has been replaced by "set serial baud".
1496 Similarly, "show remotebaud" has been replaced by "show serial baud".
1497 The "set remotebaud" and "show remotebaud" commands are still available
1498 to provide backward compatibility with older versions of GDB.
1500 *** Changes in GDB 7.6
1502 * Target record has been renamed to record-full.
1503 Record/replay is now enabled with the "record full" command.
1504 This also affects settings that are associated with full record/replay
1505 that have been moved from "set/show record" to "set/show record full":
1507 set|show record full insn-number-max
1508 set|show record full stop-at-limit
1509 set|show record full memory-query
1511 * A new record target "record-btrace" has been added. The new target
1512 uses hardware support to record the control-flow of a process. It
1513 does not support replaying the execution, but it implements the
1514 below new commands for investigating the recorded execution log.
1515 This new recording method can be enabled using:
1519 The "record-btrace" target is only available on Intel Atom processors
1520 and requires a Linux kernel 2.6.32 or later.
1522 * Two new commands have been added for record/replay to give information
1523 about the recorded execution without having to replay the execution.
1524 The commands are only supported by "record btrace".
1526 record instruction-history prints the execution history at
1527 instruction granularity
1529 record function-call-history prints the execution history at
1530 function granularity
1532 * New native configurations
1534 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1535 FreeBSD/powerpc powerpc*-*-freebsd
1536 x86_64/Cygwin x86_64-*-cygwin*
1537 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1541 ARM AArch64 aarch64*-*-elf
1542 ARM AArch64 GNU/Linux aarch64*-*-linux
1543 Lynx 178 PowerPC powerpc-*-lynx*178
1544 x86_64/Cygwin x86_64-*-cygwin*
1545 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1547 * If the configured location of system.gdbinit file (as given by the
1548 --with-system-gdbinit option at configure time) is in the
1549 data-directory (as specified by --with-gdb-datadir at configure
1550 time) or in one of its subdirectories, then GDB will look for the
1551 system-wide init file in the directory specified by the
1552 --data-directory command-line option.
1554 * New command line options:
1556 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1557 other initialization files, unlike -nx which disables all of them.
1559 * Removed command line options
1561 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1564 * The 'ptype' and 'whatis' commands now accept an argument to control
1567 * 'info proc' now works on some core files.
1571 ** Vectors can be created with gdb.Type.vector.
1573 ** Python's atexit.register now works in GDB.
1575 ** Types can be pretty-printed via a Python API.
1577 ** Python 3 is now supported (in addition to Python 2.4 or later)
1579 ** New class gdb.Architecture exposes GDB's internal representation
1580 of architecture in the Python API.
1582 ** New method Frame.architecture returns the gdb.Architecture object
1583 corresponding to the frame's architecture.
1585 * New Python-based convenience functions:
1587 ** $_memeq(buf1, buf2, length)
1588 ** $_streq(str1, str2)
1590 ** $_regex(str, regex)
1592 * The 'cd' command now defaults to using '~' (the home directory) if not
1595 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1596 default for GCC since November 2000.
1598 * The command 'forward-search' can now be abbreviated as 'fo'.
1600 * The command 'info tracepoints' can now display 'installed on target'
1601 or 'not installed on target' for each non-pending location of tracepoint.
1603 * New configure options
1605 --enable-libmcheck/--disable-libmcheck
1606 By default, development versions are built with -lmcheck on hosts
1607 that support it, in order to help track memory corruption issues.
1608 Release versions, on the other hand, are built without -lmcheck
1609 by default. The --enable-libmcheck/--disable-libmcheck configure
1610 options allow the user to override that default.
1611 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1612 This configure option allows the user to build GDB with
1613 libbabeltrace using which GDB can read Common Trace Format data.
1615 * New commands (for set/show, see "New options" below)
1618 Catch signals. This is similar to "handle", but allows commands and
1619 conditions to be attached.
1622 List the BFDs known to GDB.
1624 python-interactive [command]
1626 Start a Python interactive prompt, or evaluate the optional command
1627 and print the result of expressions.
1630 "py" is a new alias for "python".
1632 enable type-printer [name]...
1633 disable type-printer [name]...
1634 Enable or disable type printers.
1638 ** For the Renesas Super-H architecture, the "regs" command has been removed
1639 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1644 set print type methods (on|off)
1645 show print type methods
1646 Control whether method declarations are displayed by "ptype".
1647 The default is to show them.
1649 set print type typedefs (on|off)
1650 show print type typedefs
1651 Control whether typedef definitions are displayed by "ptype".
1652 The default is to show them.
1654 set filename-display basename|relative|absolute
1655 show filename-display
1656 Control the way in which filenames is displayed.
1657 The default is "relative", which preserves previous behavior.
1659 set trace-buffer-size
1660 show trace-buffer-size
1661 Request target to change the size of trace buffer.
1663 set remote trace-buffer-size-packet auto|on|off
1664 show remote trace-buffer-size-packet
1665 Control the use of the remote protocol `QTBuffer:size' packet.
1669 Control display of debugging messages related to ARM AArch64.
1672 set debug coff-pe-read
1673 show debug coff-pe-read
1674 Control display of debugging messages related to reading of COFF/PE
1679 Control display of debugging messages related to Mach-O symbols
1682 set debug notification
1683 show debug notification
1684 Control display of debugging info for async remote notification.
1688 ** Command parameter changes are now notified using new async record
1689 "=cmd-param-changed".
1690 ** Trace frame changes caused by command "tfind" are now notified using
1691 new async record "=traceframe-changed".
1692 ** The creation, deletion and modification of trace state variables
1693 are now notified using new async records "=tsv-created",
1694 "=tsv-deleted" and "=tsv-modified".
1695 ** The start and stop of process record are now notified using new
1696 async record "=record-started" and "=record-stopped".
1697 ** Memory changes are now notified using new async record
1699 ** The data-disassemble command response will include a "fullname" field
1700 containing the absolute file name when source has been requested.
1701 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1702 command, to allow pattern filling of memory areas.
1703 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1704 library load/unload events.
1705 ** The response to breakpoint commands and breakpoint async records
1706 includes an "installed" field containing a boolean state about each
1707 non-pending tracepoint location is whether installed on target or not.
1708 ** Output of the "-trace-status" command includes a "trace-file" field
1709 containing the name of the trace file being examined. This field is
1710 optional, and only present when examining a trace file.
1711 ** The "fullname" field is now always present along with the "file" field,
1712 even if the file cannot be found by GDB.
1714 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1715 You must have the LZMA library available when configuring GDB for this
1716 feature to be enabled. For more information, see:
1717 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1719 * New remote packets
1722 Set the size of trace buffer. The remote stub reports support for this
1723 packet to gdb's qSupported query.
1726 Enable Branch Trace Store (BTS)-based branch tracing for the current
1727 thread. The remote stub reports support for this packet to gdb's
1731 Disable branch tracing for the current thread. The remote stub reports
1732 support for this packet to gdb's qSupported query.
1735 Read the traced branches for the current thread. The remote stub
1736 reports support for this packet to gdb's qSupported query.
1738 *** Changes in GDB 7.5
1740 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1741 for more x32 ABI info.
1743 * GDB now supports access to MIPS DSP registers on Linux targets.
1745 * GDB now supports debugging microMIPS binaries.
1747 * The "info os" command on GNU/Linux can now display information on
1748 several new classes of objects managed by the operating system:
1749 "info os procgroups" lists process groups
1750 "info os files" lists file descriptors
1751 "info os sockets" lists internet-domain sockets
1752 "info os shm" lists shared-memory regions
1753 "info os semaphores" lists semaphores
1754 "info os msg" lists message queues
1755 "info os modules" lists loaded kernel modules
1757 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1758 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1759 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1760 options and inspect the probe arguments using the new $_probe_arg family
1761 of convenience variables. You can obtain more information about SystemTap
1762 in <http://sourceware.org/systemtap/>.
1764 * GDB now supports reversible debugging on ARM, it allows you to
1765 debug basic ARM and THUMB instructions, and provides
1766 record/replay support.
1768 * The option "symbol-reloading" has been deleted as it is no longer used.
1772 ** GDB commands implemented in Python can now be put in command class
1775 ** The "maint set python print-stack on|off" is now deleted.
1777 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1778 apply "flag enum"-style pretty-printing to any enum.
1780 ** gdb.lookup_symbol can now work when there is no current frame.
1782 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1783 the source at which the symbol was defined.
1785 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1786 method 'value'. The former indicates whether the symbol needs a
1787 frame in order to compute its value, and the latter computes the
1790 ** A new method 'referenced_value' on gdb.Value objects which can
1791 dereference pointer as well as C++ reference values.
1793 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1794 which return the global and static blocks (as gdb.Block objects),
1795 of the underlying symbol table, respectively.
1797 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1798 object associated with a PC value.
1800 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1801 of the address range occupied by code for the current source line.
1803 * Go language support.
1804 GDB now supports debugging programs written in the Go programming
1807 * GDBserver now supports stdio connections.
1808 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1810 * The binary "gdbtui" can no longer be built or installed.
1811 Use "gdb -tui" instead.
1813 * GDB will now print "flag" enums specially. A flag enum is one where
1814 all the enumerator values have no bits in common when pairwise
1815 "and"ed. When printing a value whose type is a flag enum, GDB will
1816 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1817 (gdb) print (enum E) 3
1820 * The filename part of a linespec will now match trailing components
1821 of a source file name. For example, "break gcc/expr.c:1000" will
1822 now set a breakpoint in build/gcc/expr.c, but not
1823 build/libcpp/expr.c.
1825 * The "info proc" and "generate-core-file" commands will now also
1826 work on remote targets connected to GDBserver on Linux.
1828 * The command "info catch" has been removed. It has been disabled
1829 since December 2007.
1831 * The "catch exception" and "catch assert" commands now accept
1832 a condition at the end of the command, much like the "break"
1833 command does. For instance:
1835 (gdb) catch exception Constraint_Error if Barrier = True
1837 Previously, it was possible to add a condition to such catchpoints,
1838 but it had to be done as a second step, after the catchpoint had been
1839 created, using the "condition" command.
1841 * The "info static-tracepoint-marker" command will now also work on
1842 native Linux targets with in-process agent.
1844 * GDB can now set breakpoints on inlined functions.
1846 * The .gdb_index section has been updated to include symbols for
1847 inlined functions. GDB will ignore older .gdb_index sections by
1848 default, which could cause symbol files to be loaded more slowly
1849 until their .gdb_index sections can be recreated. The new command
1850 "set use-deprecated-index-sections on" will cause GDB to use any older
1851 .gdb_index sections it finds. This will restore performance, but the
1852 ability to set breakpoints on inlined functions will be lost in symbol
1853 files with older .gdb_index sections.
1855 The .gdb_index section has also been updated to record more information
1856 about each symbol. This speeds up the "info variables", "info functions"
1857 and "info types" commands when used with programs having the .gdb_index
1858 section, as well as speeding up debugging with shared libraries using
1859 the .gdb_index section.
1861 * Ada support for GDB/MI Variable Objects has been added.
1863 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1868 ** New command -info-os is the MI equivalent of "info os".
1870 ** Output logs ("set logging" and related) now include MI output.
1874 ** "set use-deprecated-index-sections on|off"
1875 "show use-deprecated-index-sections on|off"
1876 Controls the use of deprecated .gdb_index sections.
1878 ** "catch load" and "catch unload" can be used to stop when a shared
1879 library is loaded or unloaded, respectively.
1881 ** "enable count" can be used to auto-disable a breakpoint after
1884 ** "info vtbl" can be used to show the virtual method tables for
1885 C++ and Java objects.
1887 ** "explore" and its sub commands "explore value" and "explore type"
1888 can be used to recursively explore values and types of
1889 expressions. These commands are available only if GDB is
1890 configured with '--with-python'.
1892 ** "info auto-load" shows status of all kinds of auto-loaded files,
1893 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1894 sequences of commands files, "info auto-load python-scripts"
1895 shows status of auto-loading Python script files,
1896 "info auto-load local-gdbinit" shows status of loading init file
1897 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1898 status of inferior specific thread debugging shared library loading.
1900 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1901 and "show auto-load-scripts" commands have been deprecated, use their
1902 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1903 and "show auto-load python-scripts" counterparts instead.
1905 ** "dprintf location,format,args..." creates a dynamic printf, which
1906 is basically a breakpoint that does a printf and immediately
1907 resumes your program's execution, so it is like a printf that you
1908 can insert dynamically at runtime instead of at compiletime.
1910 ** "set print symbol"
1912 Controls whether GDB attempts to display the symbol, if any,
1913 corresponding to addresses it prints. This defaults to "on", but
1914 you can set it to "off" to restore GDB's previous behavior.
1916 * Deprecated commands
1918 ** For the Renesas Super-H architecture, the "regs" command has been
1919 deprecated, and "info all-registers" should be used instead.
1923 Renesas RL78 rl78-*-elf
1924 HP OpenVMS ia64 ia64-hp-openvms*
1926 * GDBserver supports evaluation of breakpoint conditions. When
1927 support is advertised by GDBserver, GDB may be told to send the
1928 breakpoint conditions in bytecode form to GDBserver. GDBserver
1929 will only report the breakpoint trigger to GDB when its condition
1934 set mips compression
1935 show mips compression
1936 Select the compressed ISA encoding used in functions that have no symbol
1937 information available. The encoding can be set to either of:
1940 and is updated automatically from ELF file flags if available.
1942 set breakpoint condition-evaluation
1943 show breakpoint condition-evaluation
1944 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1945 GDBserver ("target"). Default option "auto" chooses the most efficient
1947 This option can improve debugger efficiency depending on the speed of the
1951 Disable auto-loading globally.
1954 Show auto-loading setting of all kinds of auto-loaded files.
1956 set auto-load gdb-scripts on|off
1957 show auto-load gdb-scripts
1958 Control auto-loading of GDB canned sequences of commands files.
1960 set auto-load python-scripts on|off
1961 show auto-load python-scripts
1962 Control auto-loading of Python script files.
1964 set auto-load local-gdbinit on|off
1965 show auto-load local-gdbinit
1966 Control loading of init file (.gdbinit) from current directory.
1968 set auto-load libthread-db on|off
1969 show auto-load libthread-db
1970 Control auto-loading of inferior specific thread debugging shared library.
1972 set auto-load scripts-directory <dir1>[:<dir2>...]
1973 show auto-load scripts-directory
1974 Set a list of directories from which to load auto-loaded scripts.
1975 Automatically loaded Python scripts and GDB scripts are located in one
1976 of the directories listed by this option.
1977 The delimiter (':' above) may differ according to the host platform.
1979 set auto-load safe-path <dir1>[:<dir2>...]
1980 show auto-load safe-path
1981 Set a list of directories from which it is safe to auto-load files.
1982 The delimiter (':' above) may differ according to the host platform.
1984 set debug auto-load on|off
1985 show debug auto-load
1986 Control display of debugging info for auto-loading the files above.
1988 set dprintf-style gdb|call|agent
1990 Control the way in which a dynamic printf is performed; "gdb"
1991 requests a GDB printf command, while "call" causes dprintf to call a
1992 function in the inferior. "agent" requests that the target agent
1993 (such as GDBserver) do the printing.
1995 set dprintf-function <expr>
1996 show dprintf-function
1997 set dprintf-channel <expr>
1998 show dprintf-channel
1999 Set the function and optional first argument to the call when using
2000 the "call" style of dynamic printf.
2002 set disconnected-dprintf on|off
2003 show disconnected-dprintf
2004 Control whether agent-style dynamic printfs continue to be in effect
2005 after GDB disconnects.
2007 * New configure options
2009 --with-auto-load-dir
2010 Configure default value for the 'set auto-load scripts-directory'
2011 setting above. It defaults to '$debugdir:$datadir/auto-load',
2012 $debugdir representing global debugging info directories (available
2013 via 'show debug-file-directory') and $datadir representing GDB's data
2014 directory (available via 'show data-directory').
2016 --with-auto-load-safe-path
2017 Configure default value for the 'set auto-load safe-path' setting
2018 above. It defaults to the --with-auto-load-dir setting.
2020 --without-auto-load-safe-path
2021 Set 'set auto-load safe-path' to '/', effectively disabling this
2024 * New remote packets
2026 z0/z1 conditional breakpoints extension
2028 The z0/z1 breakpoint insertion packets have been extended to carry
2029 a list of conditional expressions over to the remote stub depending on the
2030 condition evaluation mode. The use of this extension can be controlled
2031 via the "set remote conditional-breakpoints-packet" command.
2035 Specify the signals which the remote stub may pass to the debugged
2036 program without GDB involvement.
2038 * New command line options
2040 --init-command=FILE, -ix Like --command, -x but execute it
2041 before loading inferior.
2042 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2043 execute it before loading inferior.
2045 *** Changes in GDB 7.4
2047 * GDB now handles ambiguous linespecs more consistently; the existing
2048 FILE:LINE support has been expanded to other types of linespecs. A
2049 breakpoint will now be set on all matching locations in all
2050 inferiors, and locations will be added or removed according to
2053 * GDB now allows you to skip uninteresting functions and files when
2054 stepping with the "skip function" and "skip file" commands.
2056 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2057 and "show remote hardware-watchpoint-length-limit". These allows to
2058 set or show the maximum length limit (in bytes) of a remote
2059 target hardware watchpoint.
2061 This allows e.g. to use "unlimited" hardware watchpoints with the
2062 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2063 watchpoints are slower than real hardware watchpoints but are
2064 significantly faster than gdb software watchpoints.
2068 ** The register_pretty_printer function in module gdb.printing now takes
2069 an optional `replace' argument. If True, the new printer replaces any
2072 ** The "maint set python print-stack on|off" command has been
2073 deprecated and will be deleted in GDB 7.5.
2074 A new command: "set python print-stack none|full|message" has
2075 replaced it. Additionally, the default for "print-stack" is
2076 now "message", which just prints the error message without
2079 ** A prompt substitution hook (prompt_hook) is now available to the
2082 ** A new Python module, gdb.prompt has been added to the GDB Python
2083 modules library. This module provides functionality for
2084 escape sequences in prompts (used by set/show
2085 extended-prompt). These escape sequences are replaced by their
2086 corresponding value.
2088 ** Python commands and convenience-functions located in
2089 'data-directory'/python/gdb/command and
2090 'data-directory'/python/gdb/function are now automatically loaded
2093 ** Blocks now provide four new attributes. global_block and
2094 static_block will return the global and static blocks
2095 respectively. is_static and is_global are boolean attributes
2096 that indicate if the block is one of those two types.
2098 ** Symbols now provide the "type" attribute, the type of the symbol.
2100 ** The "gdb.breakpoint" function has been deprecated in favor of
2103 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2104 of a function. This class is based on the "finish" command
2105 available in the CLI.
2107 ** Type objects for struct and union types now allow access to
2108 the fields using standard Python dictionary (mapping) methods.
2109 For example, "some_type['myfield']" now works, as does
2110 "some_type.items()".
2112 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2115 ** A new function, "deep_items" has been added to the gdb.types
2116 module in the GDB Python modules library. This function returns
2117 an iterator over the fields of a struct or union type. Unlike
2118 the standard Python "iteritems" method, it will recursively traverse
2119 any anonymous fields.
2123 ** "*stopped" events can report several new "reason"s, such as
2126 ** Breakpoint changes are now notified using new async records, like
2127 "=breakpoint-modified".
2129 ** New command -ada-task-info.
2131 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2132 $sdir specifies the default system locations of shared libraries.
2133 $pdir specifies the directory where the libpthread used by the application
2136 GDB no longer looks in $sdir and $pdir after it has searched the directories
2137 mentioned in libthread-db-search-path. If you want to search those
2138 directories, they must be specified in libthread-db-search-path.
2139 The default value of libthread-db-search-path on GNU/Linux and Solaris
2140 systems is now "$sdir:$pdir".
2142 $pdir is not supported by gdbserver, it is currently ignored.
2143 $sdir is supported by gdbserver.
2145 * New configure option --with-iconv-bin.
2146 When using the internationalization support like the one in the GNU C
2147 library, GDB will invoke the "iconv" program to get a list of supported
2148 character sets. If this program lives in a non-standard location, one can
2149 use this option to specify where to find it.
2151 * When natively debugging programs on PowerPC BookE processors running
2152 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2153 watchpoints, which specify a mask in addition to an address to watch.
2154 The mask specifies that some bits of an address (the bits which are
2155 reset in the mask) should be ignored when matching the address accessed
2156 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2157 section in the user manual for more details.
2159 * The new option --once causes GDBserver to stop listening for connections once
2160 the first connection is made. The listening port used by GDBserver will
2161 become available after that.
2163 * New commands "info macros" and "alias" have been added.
2165 * New function parameters suffix @entry specifies value of function parameter
2166 at the time the function got called. Entry values are available only since
2172 "!" is now an alias of the "shell" command.
2173 Note that no space is needed between "!" and SHELL COMMAND.
2177 watch EXPRESSION mask MASK_VALUE
2178 The watch command now supports the mask argument which allows creation
2179 of masked watchpoints, if the current architecture supports this feature.
2181 info auto-load-scripts [REGEXP]
2182 This command was formerly named "maintenance print section-scripts".
2183 It is now generally useful and is no longer a maintenance-only command.
2185 info macro [-all] [--] MACRO
2186 The info macro command has new options `-all' and `--'. The first for
2187 printing all definitions of a macro. The second for explicitly specifying
2188 the end of arguments and the beginning of the macro name in case the macro
2189 name starts with a hyphen.
2191 collect[/s] EXPRESSIONS
2192 The tracepoint collect command now takes an optional modifier "/s"
2193 that directs it to dereference pointer-to-character types and
2194 collect the bytes of memory up to a zero byte. The behavior is
2195 similar to what you see when you use the regular print command on a
2196 string. An optional integer following the "/s" sets a bound on the
2197 number of bytes that will be collected.
2200 The trace start command now interprets any supplied arguments as a
2201 note to be recorded with the trace run, with an effect similar to
2202 setting the variable trace-notes.
2205 The trace stop command now interprets any arguments as a note to be
2206 mentioned along with the tstatus report that the trace was stopped
2207 with a command. The effect is similar to setting the variable
2210 * Tracepoints can now be enabled and disabled at any time after a trace
2211 experiment has been started using the standard "enable" and "disable"
2212 commands. It is now possible to start a trace experiment with no enabled
2213 tracepoints; GDB will display a warning, but will allow the experiment to
2214 begin, assuming that tracepoints will be enabled as needed while the trace
2217 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2218 locations with 4-byte instructions, when they were previously
2219 limited to locations with instructions of 5 bytes or longer.
2223 set debug dwarf2-read
2224 show debug dwarf2-read
2225 Turns on or off display of debugging messages related to reading
2226 DWARF debug info. The default is off.
2228 set debug symtab-create
2229 show debug symtab-create
2230 Turns on or off display of debugging messages related to symbol table
2231 creation. The default is off.
2234 show extended-prompt
2235 Set the GDB prompt, and allow escape sequences to be inserted to
2236 display miscellaneous information (see 'help set extended-prompt'
2237 for the list of sequences). This prompt (and any information
2238 accessed through the escape sequences) is updated every time the
2239 prompt is displayed.
2241 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2242 show print entry-values
2243 Set printing of frame argument values at function entry. In some cases
2244 GDB can determine the value of function argument which was passed by the
2245 function caller, even if the value was modified inside the called function.
2247 set debug entry-values
2248 show debug entry-values
2249 Control display of debugging info for determining frame argument values at
2250 function entry and virtual tail call frames.
2252 set basenames-may-differ
2253 show basenames-may-differ
2254 Set whether a source file may have multiple base names.
2255 (A "base name" is the name of a file with the directory part removed.
2256 Example: The base name of "/home/user/hello.c" is "hello.c".)
2257 If set, GDB will canonicalize file names (e.g., expand symlinks)
2258 before comparing them. Canonicalization is an expensive operation,
2259 but it allows the same file be known by more than one base name.
2260 If not set (the default), all source files are assumed to have just
2261 one base name, and gdb will do file name comparisons more efficiently.
2267 Set a user name and notes for the current and any future trace runs.
2268 This is useful for long-running and/or disconnected traces, to
2269 inform others (or yourself) as to who is running the trace, supply
2270 contact information, or otherwise explain what is going on.
2272 set trace-stop-notes
2273 show trace-stop-notes
2274 Set a note attached to the trace run, that is displayed when the
2275 trace has been stopped by a tstop command. This is useful for
2276 instance as an explanation, if you are stopping a trace run that was
2277 started by someone else.
2279 * New remote packets
2283 Dynamically enable a tracepoint in a started trace experiment.
2287 Dynamically disable a tracepoint in a started trace experiment.
2291 Set the user and notes of the trace run.
2295 Query the current status of a tracepoint.
2299 Query the minimum length of instruction at which a fast tracepoint may
2302 * Dcache size (number of lines) and line-size are now runtime-configurable
2303 via "set dcache line" and "set dcache line-size" commands.
2307 Texas Instruments TMS320C6x tic6x-*-*
2311 Renesas RL78 rl78-*-elf
2313 *** Changes in GDB 7.3.1
2315 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2317 *** Changes in GDB 7.3
2319 * GDB has a new command: "thread find [REGEXP]".
2320 It finds the thread id whose name, target id, or thread extra info
2321 matches the given regular expression.
2323 * The "catch syscall" command now works on mips*-linux* targets.
2325 * The -data-disassemble MI command now supports modes 2 and 3 for
2326 dumping the instruction opcodes.
2328 * New command line options
2330 -data-directory DIR Specify DIR as the "data-directory".
2331 This is mostly for testing purposes.
2333 * The "maint set python auto-load on|off" command has been renamed to
2334 "set auto-load-scripts on|off".
2336 * GDB has a new command: "set directories".
2337 It is like the "dir" command except that it replaces the
2338 source path list instead of augmenting it.
2340 * GDB now understands thread names.
2342 On GNU/Linux, "info threads" will display the thread name as set by
2343 prctl or pthread_setname_np.
2345 There is also a new command, "thread name", which can be used to
2346 assign a name internally for GDB to display.
2349 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2350 has been integrated into GDB.
2354 ** The function gdb.Write now accepts an optional keyword 'stream'.
2355 This keyword, when provided, will direct the output to either
2356 stdout, stderr, or GDB's logging output.
2358 ** Parameters can now be be sub-classed in Python, and in particular
2359 you may implement the get_set_doc and get_show_doc functions.
2360 This improves how Parameter set/show documentation is processed
2361 and allows for more dynamic content.
2363 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2364 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2365 have an is_valid method.
2367 ** Breakpoints can now be sub-classed in Python, and in particular
2368 you may implement a 'stop' function that is executed each time
2369 the inferior reaches that breakpoint.
2371 ** New function gdb.lookup_global_symbol looks up a global symbol.
2373 ** GDB values in Python are now callable if the value represents a
2374 function. For example, if 'some_value' represents a function that
2375 takes two integer parameters and returns a value, you can call
2376 that function like so:
2378 result = some_value (10,20)
2380 ** Module gdb.types has been added.
2381 It contains a collection of utilities for working with gdb.Types objects:
2382 get_basic_type, has_field, make_enum_dict.
2384 ** Module gdb.printing has been added.
2385 It contains utilities for writing and registering pretty-printers.
2386 New classes: PrettyPrinter, SubPrettyPrinter,
2387 RegexpCollectionPrettyPrinter.
2388 New function: register_pretty_printer.
2390 ** New commands "info pretty-printers", "enable pretty-printer" and
2391 "disable pretty-printer" have been added.
2393 ** gdb.parameter("directories") is now available.
2395 ** New function gdb.newest_frame returns the newest frame in the
2398 ** The gdb.InferiorThread class has a new "name" attribute. This
2399 holds the thread's name.
2401 ** Python Support for Inferior events.
2402 Python scripts can add observers to be notified of events
2403 occurring in the process being debugged.
2404 The following events are currently supported:
2405 - gdb.events.cont Continue event.
2406 - gdb.events.exited Inferior exited event.
2407 - gdb.events.stop Signal received, and Breakpoint hit events.
2411 ** GDB now puts template parameters in scope when debugging in an
2412 instantiation. For example, if you have:
2414 template<int X> int func (void) { return X; }
2416 then if you step into func<5>, "print X" will show "5". This
2417 feature requires proper debuginfo support from the compiler; it
2418 was added to GCC 4.5.
2420 ** The motion commands "next", "finish", "until", and "advance" now
2421 work better when exceptions are thrown. In particular, GDB will
2422 no longer lose control of the inferior; instead, the GDB will
2423 stop the inferior at the point at which the exception is caught.
2424 This functionality requires a change in the exception handling
2425 code that was introduced in GCC 4.5.
2427 * GDB now follows GCC's rules on accessing volatile objects when
2428 reading or writing target state during expression evaluation.
2429 One notable difference to prior behavior is that "print x = 0"
2430 no longer generates a read of x; the value of the assignment is
2431 now always taken directly from the value being assigned.
2433 * GDB now has some support for using labels in the program's source in
2434 linespecs. For instance, you can use "advance label" to continue
2435 execution to a label.
2437 * GDB now has support for reading and writing a new .gdb_index
2438 section. This section holds a fast index of DWARF debugging
2439 information and can be used to greatly speed up GDB startup and
2440 operation. See the documentation for `save gdb-index' for details.
2442 * The "watch" command now accepts an optional "-location" argument.
2443 When used, this causes GDB to watch the memory referred to by the
2444 expression. Such a watchpoint is never deleted due to it going out
2447 * GDB now supports thread debugging of core dumps on GNU/Linux.
2449 GDB now activates thread debugging using the libthread_db library
2450 when debugging GNU/Linux core dumps, similarly to when debugging
2451 live processes. As a result, when debugging a core dump file, GDB
2452 is now able to display pthread_t ids of threads. For example, "info
2453 threads" shows the same output as when debugging the process when it
2454 was live. In earlier releases, you'd see something like this:
2457 * 1 LWP 6780 main () at main.c:10
2459 While now you see this:
2462 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2464 It is also now possible to inspect TLS variables when debugging core
2467 When debugging a core dump generated on a machine other than the one
2468 used to run GDB, you may need to point GDB at the correct
2469 libthread_db library with the "set libthread-db-search-path"
2470 command. See the user manual for more details on this command.
2472 * When natively debugging programs on PowerPC BookE processors running
2473 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2474 which stop execution of the inferior whenever it executes an instruction
2475 at any address within the specified range. See the "PowerPC Embedded"
2476 section in the user manual for more details.
2478 * New features in the GDB remote stub, GDBserver
2480 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2481 and i686 LynxOS (version 5.x).
2483 ** GDBserver is now supported on Blackfin Linux.
2485 * New native configurations
2487 ia64 HP-UX ia64-*-hpux*
2491 Analog Devices, Inc. Blackfin Processor bfin-*
2493 * Ada task switching is now supported on sparc-elf targets when
2494 debugging a program using the Ravenscar Profile. For more information,
2495 see the "Tasking Support when using the Ravenscar Profile" section
2496 in the GDB user manual.
2498 * Guile support was removed.
2500 * New features in the GNU simulator
2502 ** The --map-info flag lists all known core mappings.
2504 ** CFI flashes may be simulated via the "cfi" device.
2506 *** Changes in GDB 7.2
2508 * Shared library support for remote targets by default
2510 When GDB is configured for a generic, non-OS specific target, like
2511 for example, --target=arm-eabi or one of the many *-*-elf targets,
2512 GDB now queries remote stubs for loaded shared libraries using the
2513 `qXfer:libraries:read' packet. Previously, shared library support
2514 was always disabled for such configurations.
2518 ** Argument Dependent Lookup (ADL)
2520 In C++ ADL lookup directs function search to the namespaces of its
2521 arguments even if the namespace has not been imported.
2531 Here the compiler will search for `foo' in the namespace of 'b'
2532 and find A::foo. GDB now supports this. This construct is commonly
2533 used in the Standard Template Library for operators.
2535 ** Improved User Defined Operator Support
2537 In addition to member operators, GDB now supports lookup of operators
2538 defined in a namespace and imported with a `using' directive, operators
2539 defined in the global scope, operators imported implicitly from an
2540 anonymous namespace, and the ADL operators mentioned in the previous
2542 GDB now also supports proper overload resolution for all the previously
2543 mentioned flavors of operators.
2545 ** static const class members
2547 Printing of static const class members that are initialized in the
2548 class definition has been fixed.
2550 * Windows Thread Information Block access.
2552 On Windows targets, GDB now supports displaying the Windows Thread
2553 Information Block (TIB) structure. This structure is visible either
2554 by using the new command `info w32 thread-information-block' or, by
2555 dereferencing the new convenience variable named `$_tlb', a
2556 thread-specific pointer to the TIB. This feature is also supported
2557 when remote debugging using GDBserver.
2559 * Static tracepoints
2561 Static tracepoints are calls in the user program into a tracing
2562 library. One such library is a port of the LTTng kernel tracer to
2563 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2564 When debugging with GDBserver, GDB now supports combining the GDB
2565 tracepoint machinery with such libraries. For example: the user can
2566 use GDB to probe a static tracepoint marker (a call from the user
2567 program into the tracing library) with the new "strace" command (see
2568 "New commands" below). This creates a "static tracepoint" in the
2569 breakpoint list, that can be manipulated with the same feature set
2570 as fast and regular tracepoints. E.g., collect registers, local and
2571 global variables, collect trace state variables, and define
2572 tracepoint conditions. In addition, the user can collect extra
2573 static tracepoint marker specific data, by collecting the new
2574 $_sdata internal variable. When analyzing the trace buffer, you can
2575 inspect $_sdata like any other variable available to GDB. For more
2576 information, see the "Tracepoints" chapter in GDB user manual. New
2577 remote packets have been defined to support static tracepoints, see
2578 the "New remote packets" section below.
2580 * Better reconstruction of tracepoints after disconnected tracing
2582 GDB will attempt to download the original source form of tracepoint
2583 definitions when starting a trace run, and then will upload these
2584 upon reconnection to the target, resulting in a more accurate
2585 reconstruction of the tracepoints that are in use on the target.
2589 You can now exercise direct control over the ways that GDB can
2590 affect your program. For instance, you can disallow the setting of
2591 breakpoints, so that the program can run continuously (assuming
2592 non-stop mode). In addition, the "observer" variable is available
2593 to switch all of the different controls; in observer mode, GDB
2594 cannot affect the target's behavior at all, which is useful for
2595 tasks like diagnosing live systems in the field.
2597 * The new convenience variable $_thread holds the number of the
2600 * New remote packets
2604 Return the address of the Windows Thread Information Block of a given thread.
2608 In response to several of the tracepoint packets, the target may now
2609 also respond with a number of intermediate `qRelocInsn' request
2610 packets before the final result packet, to have GDB handle
2611 relocating an instruction to execute at a different address. This
2612 is particularly useful for stubs that support fast tracepoints. GDB
2613 reports support for this feature in the qSupported packet.
2617 List static tracepoint markers in the target program.
2621 List static tracepoint markers at a given address in the target
2624 qXfer:statictrace:read
2626 Read the static trace data collected (by a `collect $_sdata'
2627 tracepoint action). The remote stub reports support for this packet
2628 to gdb's qSupported query.
2632 Send the current settings of GDB's permission flags.
2636 Send part of the source (textual) form of a tracepoint definition,
2637 which includes location, conditional, and action list.
2639 * The source command now accepts a -s option to force searching for the
2640 script in the source search path even if the script name specifies
2643 * New features in the GDB remote stub, GDBserver
2645 - GDBserver now support tracepoints (including fast tracepoints, and
2646 static tracepoints). The feature is currently supported by the
2647 i386-linux and amd64-linux builds. See the "Tracepoints support
2648 in gdbserver" section in the manual for more information.
2650 GDBserver JIT compiles the tracepoint's conditional agent
2651 expression bytecode into native code whenever possible for low
2652 overhead dynamic tracepoints conditionals. For such tracepoints,
2653 an expression that examines program state is evaluated when the
2654 tracepoint is reached, in order to determine whether to capture
2655 trace data. If the condition is simple and false, processing the
2656 tracepoint finishes very quickly and no data is gathered.
2658 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2659 for static tracepoints support.
2661 - GDBserver now supports x86_64 Windows 64-bit debugging.
2663 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2664 it understands register description.
2666 * The --batch flag now disables pagination and queries.
2668 * X86 general purpose registers
2670 GDB now supports reading/writing byte, word and double-word x86
2671 general purpose registers directly. This means you can use, say,
2672 $ah or $ax to refer, respectively, to the byte register AH and
2673 16-bit word register AX that are actually portions of the 32-bit
2674 register EAX or 64-bit register RAX.
2676 * The `commands' command now accepts a range of breakpoints to modify.
2677 A plain `commands' following a command that creates multiple
2678 breakpoints affects all the breakpoints set by that command. This
2679 applies to breakpoints set by `rbreak', and also applies when a
2680 single `break' command creates multiple breakpoints (e.g.,
2681 breakpoints on overloaded c++ functions).
2683 * The `rbreak' command now accepts a filename specification as part of
2684 its argument, limiting the functions selected by the regex to those
2685 in the specified file.
2687 * Support for remote debugging Windows and SymbianOS shared libraries
2688 from Unix hosts has been improved. Non Windows GDB builds now can
2689 understand target reported file names that follow MS-DOS based file
2690 system semantics, such as file names that include drive letters and
2691 use the backslash character as directory separator. This makes it
2692 possible to transparently use the "set sysroot" and "set
2693 solib-search-path" on Unix hosts to point as host copies of the
2694 target's shared libraries. See the new command "set
2695 target-file-system-kind" described below, and the "Commands to
2696 specify files" section in the user manual for more information.
2700 eval template, expressions...
2701 Convert the values of one or more expressions under the control
2702 of the string template to a command line, and call it.
2704 set target-file-system-kind unix|dos-based|auto
2705 show target-file-system-kind
2706 Set or show the assumed file system kind for target reported file
2709 save breakpoints <filename>
2710 Save all current breakpoint definitions to a file suitable for use
2711 in a later debugging session. To read the saved breakpoint
2712 definitions, use the `source' command.
2714 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2717 info static-tracepoint-markers
2718 Display information about static tracepoint markers in the target.
2720 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2721 Define a static tracepoint by probing a marker at the given
2722 function, line, address, or marker ID.
2726 Enable and disable observer mode.
2728 set may-write-registers on|off
2729 set may-write-memory on|off
2730 set may-insert-breakpoints on|off
2731 set may-insert-tracepoints on|off
2732 set may-insert-fast-tracepoints on|off
2733 set may-interrupt on|off
2734 Set individual permissions for GDB effects on the target. Note that
2735 some of these settings can have undesirable or surprising
2736 consequences, particularly when changed in the middle of a session.
2737 For instance, disabling the writing of memory can prevent
2738 breakpoints from being inserted, cause single-stepping to fail, or
2739 even crash your program, if you disable after breakpoints have been
2740 inserted. However, GDB should not crash.
2742 set record memory-query on|off
2743 show record memory-query
2744 Control whether to stop the inferior if memory changes caused
2745 by an instruction cannot be recorded.
2750 The disassemble command now supports "start,+length" form of two arguments.
2754 ** GDB now provides a new directory location, called the python directory,
2755 where Python scripts written for GDB can be installed. The location
2756 of that directory is <data-directory>/python, where <data-directory>
2757 is the GDB data directory. For more details, see section `Scripting
2758 GDB using Python' in the manual.
2760 ** The GDB Python API now has access to breakpoints, symbols, symbol
2761 tables, program spaces, inferiors, threads and frame's code blocks.
2762 Additionally, GDB Parameters can now be created from the API, and
2763 manipulated via set/show in the CLI.
2765 ** New functions gdb.target_charset, gdb.target_wide_charset,
2766 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2768 ** New exception gdb.GdbError.
2770 ** Pretty-printers are now also looked up in the current program space.
2772 ** Pretty-printers can now be individually enabled and disabled.
2774 ** GDB now looks for names of Python scripts to auto-load in a
2775 special section named `.debug_gdb_scripts', in addition to looking
2776 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2778 * Tracepoint actions were unified with breakpoint commands. In particular,
2779 there are no longer differences in "info break" output for breakpoints and
2780 tracepoints and the "commands" command can be used for both tracepoints and
2781 regular breakpoints.
2785 ARM Symbian arm*-*-symbianelf*
2787 * D language support.
2788 GDB now supports debugging programs written in the D programming
2791 * GDB now supports the extended ptrace interface for PowerPC which is
2792 available since Linux kernel version 2.6.34. This automatically enables
2793 any hardware breakpoints and additional hardware watchpoints available in
2794 the processor. The old ptrace interface exposes just one hardware
2795 watchpoint and no hardware breakpoints.
2797 * GDB is now able to use the Data Value Compare (DVC) register available on
2798 embedded PowerPC processors to implement in hardware simple watchpoint
2799 conditions of the form:
2801 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2803 This works in native GDB running on Linux kernels with the extended ptrace
2804 interface mentioned above.
2806 *** Changes in GDB 7.1
2810 ** Namespace Support
2812 GDB now supports importing of namespaces in C++. This enables the
2813 user to inspect variables from imported namespaces. Support for
2814 namepace aliasing has also been added. So, if a namespace is
2815 aliased in the current scope (e.g. namepace C=A; ) the user can
2816 print variables using the alias (e.g. (gdb) print C::x).
2820 All known bugs relating to the printing of virtual base class were
2821 fixed. It is now possible to call overloaded static methods using a
2826 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2827 and reinterpret_cast<> are now handled by the C++ expression parser.
2831 Xilinx MicroBlaze microblaze-*-*
2836 Xilinx MicroBlaze microblaze
2839 * Multi-program debugging.
2841 GDB now has support for multi-program (a.k.a. multi-executable or
2842 multi-exec) debugging. This allows for debugging multiple inferiors
2843 simultaneously each running a different program under the same GDB
2844 session. See "Debugging Multiple Inferiors and Programs" in the
2845 manual for more information. This implied some user visible changes
2846 in the multi-inferior support. For example, "info inferiors" now
2847 lists inferiors that are not running yet or that have exited
2848 already. See also "New commands" and "New options" below.
2850 * New tracing features
2852 GDB's tracepoint facility now includes several new features:
2854 ** Trace state variables
2856 GDB tracepoints now include support for trace state variables, which
2857 are variables managed by the target agent during a tracing
2858 experiment. They are useful for tracepoints that trigger each
2859 other, so for instance one tracepoint can count hits in a variable,
2860 and then a second tracepoint has a condition that is true when the
2861 count reaches a particular value. Trace state variables share the
2862 $-syntax of GDB convenience variables, and can appear in both
2863 tracepoint actions and condition expressions. Use the "tvariable"
2864 command to create, and "info tvariables" to view; see "Trace State
2865 Variables" in the manual for more detail.
2869 GDB now includes an option for defining fast tracepoints, which
2870 targets may implement more efficiently, such as by installing a jump
2871 into the target agent rather than a trap instruction. The resulting
2872 speedup can be by two orders of magnitude or more, although the
2873 tradeoff is that some program locations on some target architectures
2874 might not allow fast tracepoint installation, for instance if the
2875 instruction to be replaced is shorter than the jump. To request a
2876 fast tracepoint, use the "ftrace" command, with syntax identical to
2877 the regular trace command.
2879 ** Disconnected tracing
2881 It is now possible to detach GDB from the target while it is running
2882 a trace experiment, then reconnect later to see how the experiment
2883 is going. In addition, a new variable disconnected-tracing lets you
2884 tell the target agent whether to continue running a trace if the
2885 connection is lost unexpectedly.
2889 GDB now has the ability to save the trace buffer into a file, and
2890 then use that file as a target, similarly to you can do with
2891 corefiles. You can select trace frames, print data that was
2892 collected in them, and use tstatus to display the state of the
2893 tracing run at the moment that it was saved. To create a trace
2894 file, use "tsave <filename>", and to use it, do "target tfile
2897 ** Circular trace buffer
2899 You can ask the target agent to handle the trace buffer as a
2900 circular buffer, discarding the oldest trace frames to make room for
2901 newer ones, by setting circular-trace-buffer to on. This feature may
2902 not be available for all target agents.
2907 The disassemble command, when invoked with two arguments, now requires
2908 the arguments to be comma-separated.
2911 The info variables command now displays variable definitions. Files
2912 which only declare a variable are not shown.
2915 The source command is now capable of sourcing Python scripts.
2916 This feature is dependent on the debugger being build with Python
2919 Related to this enhancement is also the introduction of a new command
2920 "set script-extension" (see below).
2922 * New commands (for set/show, see "New options" below)
2924 record save [<FILENAME>]
2925 Save a file (in core file format) containing the process record
2926 execution log for replay debugging at a later time.
2928 record restore <FILENAME>
2929 Restore the process record execution log that was saved at an
2930 earlier time, for replay debugging.
2932 add-inferior [-copies <N>] [-exec <FILENAME>]
2935 clone-inferior [-copies <N>] [ID]
2936 Make a new inferior ready to execute the same program another
2937 inferior has loaded.
2942 maint info program-spaces
2943 List the program spaces loaded into GDB.
2945 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2946 show remote interrupt-sequence
2947 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2948 as the sequence to the remote target in order to interrupt the execution.
2949 Ctrl-C is a default. Some system prefers BREAK which is high level of
2950 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2951 Magic SysRq g. It is BREAK signal and character 'g'.
2953 set remote interrupt-on-connect [on | off]
2954 show remote interrupt-on-connect
2955 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2956 remote target when gdb connects to it. This is needed when you debug
2959 set remotebreak [on | off]
2961 Deprecated. Use "set/show remote interrupt-sequence" instead.
2963 tvariable $NAME [ = EXP ]
2964 Create or modify a trace state variable.
2967 List trace state variables and their values.
2969 delete tvariable $NAME ...
2970 Delete one or more trace state variables.
2973 Evaluate the given expressions without collecting anything into the
2974 trace buffer. (Valid in tracepoint actions only.)
2976 ftrace FN / FILE:LINE / *ADDR
2977 Define a fast tracepoint at the given function, line, or address.
2979 * New expression syntax
2981 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2982 GDB now parses 0b101010 identically with 42.
2986 set follow-exec-mode new|same
2987 show follow-exec-mode
2988 Control whether GDB reuses the same inferior across an exec call or
2989 creates a new one. This is useful to be able to restart the old
2990 executable after the inferior having done an exec call.
2992 set default-collect EXPR, ...
2993 show default-collect
2994 Define a list of expressions to be collected at each tracepoint.
2995 This is a useful way to ensure essential items are not overlooked,
2996 such as registers or a critical global variable.
2998 set disconnected-tracing
2999 show disconnected-tracing
3000 If set to 1, the target is instructed to continue tracing if it
3001 loses its connection to GDB. If 0, the target is to stop tracing
3004 set circular-trace-buffer
3005 show circular-trace-buffer
3006 If set to on, the target is instructed to use a circular trace buffer
3007 and discard the oldest trace frames instead of stopping the trace due
3008 to a full trace buffer. If set to off, the trace stops when the buffer
3009 fills up. Some targets may not support this.
3011 set script-extension off|soft|strict
3012 show script-extension
3013 If set to "off", the debugger does not perform any script language
3014 recognition, and all sourced files are assumed to be GDB scripts.
3015 If set to "soft" (the default), files are sourced according to
3016 filename extension, falling back to GDB scripts if the first
3018 If set to "strict", files are sourced according to filename extension.
3020 set ada trust-PAD-over-XVS on|off
3021 show ada trust-PAD-over-XVS
3022 If off, activate a workaround against a bug in the debugging information
3023 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3024 the GCC sources for more information about the GNAT encoding and
3025 PAD types in particular). It is always safe to set this option to
3026 off, but this introduces a slight performance penalty. The default
3029 * Python API Improvements
3031 ** GDB provides the new class gdb.LazyString. This is useful in
3032 some pretty-printing cases. The new method gdb.Value.lazy_string
3033 provides a simple way to create objects of this type.
3035 ** The fields returned by gdb.Type.fields now have an
3036 `is_base_class' attribute.
3038 ** The new method gdb.Type.range returns the range of an array type.
3040 ** The new method gdb.parse_and_eval can be used to parse and
3041 evaluate an expression.
3043 * New remote packets
3046 Define a trace state variable.
3049 Get the current value of a trace state variable.
3052 Set desired tracing behavior upon disconnection.
3055 Set the trace buffer to be linear or circular.
3058 Get data about the tracepoints currently in use.
3062 Process record now works correctly with hardware watchpoints.
3064 Multiple bug fixes have been made to the mips-irix port, making it
3065 much more reliable. In particular:
3066 - Debugging threaded applications is now possible again. Previously,
3067 GDB would hang while starting the program, or while waiting for
3068 the program to stop at a breakpoint.
3069 - Attaching to a running process no longer hangs.
3070 - An error occurring while loading a core file has been fixed.
3071 - Changing the value of the PC register now works again. This fixes
3072 problems observed when using the "jump" command, or when calling
3073 a function from GDB, or even when assigning a new value to $pc.
3074 - With the "finish" and "return" commands, the return value for functions
3075 returning a small array is now correctly printed.
3076 - It is now possible to break on shared library code which gets executed
3077 during a shared library init phase (code executed while executing
3078 their .init section). Previously, the breakpoint would have no effect.
3079 - GDB is now able to backtrace through the signal handler for
3080 non-threaded programs.
3082 PIE (Position Independent Executable) programs debugging is now supported.
3083 This includes debugging execution of PIC (Position Independent Code) shared
3084 libraries although for that, it should be possible to run such libraries as an
3087 *** Changes in GDB 7.0
3089 * GDB now has an interface for JIT compilation. Applications that
3090 dynamically generate code can create symbol files in memory and register
3091 them with GDB. For users, the feature should work transparently, and
3092 for JIT developers, the interface is documented in the GDB manual in the
3093 "JIT Compilation Interface" chapter.
3095 * Tracepoints may now be conditional. The syntax is as for
3096 breakpoints; either an "if" clause appended to the "trace" command,
3097 or the "condition" command is available. GDB sends the condition to
3098 the target for evaluation using the same bytecode format as is used
3099 for tracepoint actions.
3101 * The disassemble command now supports: an optional /r modifier, print the
3102 raw instructions in hex as well as in symbolic form, and an optional /m
3103 modifier to print mixed source+assembly.
3105 * Process record and replay
3107 In a architecture environment that supports ``process record and
3108 replay'', ``process record and replay'' target can record a log of
3109 the process execution, and replay it with both forward and reverse
3112 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3113 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3114 set execution-direction {forward|reverse}, for targets that support
3117 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3118 feature is available with a native GDB running on kernel version
3121 * GDB now has support for multi-byte and wide character sets on the
3122 target. Strings whose character type is wchar_t, char16_t, or
3123 char32_t are now correctly printed. GDB supports wide- and unicode-
3124 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3125 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3126 `printf'. This feature requires iconv to work properly; if your
3127 system does not have a working iconv, GDB can use GNU libiconv. See
3128 the installation instructions for more information.
3130 * GDB now supports automatic retrieval of shared library files from
3131 remote targets. To use this feature, specify a system root that begins
3132 with the `remote:' prefix, either via the `set sysroot' command or via
3133 the `--with-sysroot' configure-time option.
3135 * "info sharedlibrary" now takes an optional regex of libraries to show,
3136 and it now reports if a shared library has no debugging information.
3138 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3139 now complete on file names.
3141 * When completing in expressions, gdb will attempt to limit
3142 completions to allowable structure or union fields, where appropriate.
3143 For instance, consider:
3145 # struct example { int f1; double f2; };
3146 # struct example variable;
3149 If the user types TAB at the end of this command line, the available
3150 completions will be "f1" and "f2".
3152 * Inlined functions are now supported. They show up in backtraces, and
3153 the "step", "next", and "finish" commands handle them automatically.
3155 * GDB now supports the token-splicing (##) and stringification (#)
3156 operators when expanding macros. It also supports variable-arity
3159 * GDB now supports inspecting extra signal information, exported by
3160 the new $_siginfo convenience variable. The feature is currently
3161 implemented on linux ARM, i386 and amd64.
3163 * GDB can now display the VFP floating point registers and NEON vector
3164 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3165 can provide these registers (requires Linux 2.6.30 or later). Remote
3166 and simulator targets may also provide them.
3168 * New remote packets
3171 Search memory for a sequence of bytes.
3174 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3175 operation over reliable transport links. Use of this packet is
3176 controlled by the `set remote noack-packet' command.
3179 Kill the process with the specified process ID. Use this in preference
3180 to `k' when multiprocess protocol extensions are supported.
3183 Obtains additional operating system information
3187 Read or write additional signal information.
3189 * Removed remote protocol undocumented extension
3191 An undocumented extension to the remote protocol's `S' stop reply
3192 packet that permited the stub to pass a process id was removed.
3193 Remote servers should use the `T' stop reply packet instead.
3195 * GDB now supports multiple function calling conventions according to the
3196 DWARF-2 DW_AT_calling_convention function attribute.
3198 * The SH target utilizes the aforementioned change to distinguish between gcc
3199 and Renesas calling convention. It also adds the new CLI commands
3200 `set/show sh calling-convention'.
3202 * GDB can now read compressed debug sections, as produced by GNU gold
3203 with the --compress-debug-sections=zlib flag.
3205 * 64-bit core files are now supported on AIX.
3207 * Thread switching is now supported on Tru64.
3209 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3210 which will be allocated using malloc later in program execution.
3212 * The qXfer:libraries:read remote procotol packet now allows passing a
3213 list of section offsets.
3215 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3216 conditions handling signals delivered during attach or thread creation
3217 have also been fixed.
3219 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3220 From the user's standpoint, all unqualified instances of True and False
3221 are treated as the standard definitions, regardless of context.
3223 * GDB now parses C++ symbol and type names more flexibly. For
3226 template<typename T> class C { };
3229 GDB will now correctly handle all of:
3231 ptype C<char const *>
3232 ptype C<char const*>
3233 ptype C<const char *>
3234 ptype C<const char*>
3236 * New features in the GDB remote stub, gdbserver
3238 - The "--wrapper" command-line argument tells gdbserver to use a
3239 wrapper program to launch programs for debugging.
3241 - On PowerPC and S/390 targets, it is now possible to use a single
3242 gdbserver executable to debug both 32-bit and 64-bit programs.
3243 (This requires gdbserver itself to be built as a 64-bit executable.)
3245 - gdbserver uses the new noack protocol mode for TCP connections to
3246 reduce communications latency, if also supported and enabled in GDB.
3248 - Support for the sparc64-linux-gnu target is now included in
3251 - The amd64-linux build of gdbserver now supports debugging both
3252 32-bit and 64-bit programs.
3254 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3255 now support hardware watchpoints, and will use them automatically
3260 GDB now has support for scripting using Python. Whether this is
3261 available is determined at configure time.
3263 New GDB commands can now be written in Python.
3265 * Ada tasking support
3267 Ada tasks can now be inspected in GDB. The following commands have
3271 Print the list of Ada tasks.
3273 Print detailed information about task number N.
3275 Print the task number of the current task.
3277 Switch the context of debugging to task number N.
3279 * Support for user-defined prefixed commands. The "define" command can
3280 add new commands to existing prefixes, e.g. "target".
3282 * Multi-inferior, multi-process debugging.
3284 GDB now has generalized support for multi-inferior debugging. See
3285 "Debugging Multiple Inferiors" in the manual for more information.
3286 Although availability still depends on target support, the command
3287 set is more uniform now. The GNU/Linux specific multi-forks support
3288 has been migrated to this new framework. This implied some user
3289 visible changes; see "New commands" and also "Removed commands"
3292 * Target descriptions can now describe the target OS ABI. See the
3293 "Target Description Format" section in the user manual for more
3296 * Target descriptions can now describe "compatible" architectures
3297 to indicate that the target can execute applications for a different
3298 architecture in addition to those for the main target architecture.
3299 See the "Target Description Format" section in the user manual for
3302 * Multi-architecture debugging.
3304 GDB now includes general supports for debugging applications on
3305 hybrid systems that use more than one single processor architecture
3306 at the same time. Each such hybrid architecture still requires
3307 specific support to be added. The only hybrid architecture supported
3308 in this version of GDB is the Cell Broadband Engine.
3310 * GDB now supports integrated debugging of Cell/B.E. applications that
3311 use both the PPU and SPU architectures. To enable support for hybrid
3312 Cell/B.E. debugging, you need to configure GDB to support both the
3313 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3314 --enable-targets configure option.
3316 * Non-stop mode debugging.
3318 For some targets, GDB now supports an optional mode of operation in
3319 which you can examine stopped threads while other threads continue
3320 to execute freely. This is referred to as non-stop mode, with the
3321 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3322 section in the user manual for more information.
3324 To be able to support remote non-stop debugging, a remote stub needs
3325 to implement the non-stop mode remote protocol extensions, as
3326 described in the "Remote Non-Stop" section of the user manual. The
3327 GDB remote stub, gdbserver, has been adjusted to support these
3328 extensions on linux targets.
3330 * New commands (for set/show, see "New options" below)
3332 catch syscall [NAME(S) | NUMBER(S)]
3333 Catch system calls. Arguments, which should be names of system
3334 calls or their numbers, mean catch only those syscalls. Without
3335 arguments, every syscall will be caught. When the inferior issues
3336 any of the specified syscalls, GDB will stop and announce the system
3337 call, both when it is called and when its call returns. This
3338 feature is currently available with a native GDB running on the
3339 Linux Kernel, under the following architectures: x86, x86_64,
3340 PowerPC and PowerPC64.
3342 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3344 Search memory for a sequence of bytes.
3346 maint set python print-stack
3347 maint show python print-stack
3348 Show a stack trace when an error is encountered in a Python script.
3351 Invoke CODE by passing it to the Python interpreter.
3356 These allow macros to be defined, undefined, and listed
3360 Show operating system information about processes.
3363 List the inferiors currently under GDB's control.
3366 Switch focus to inferior number NUM.
3369 Detach from inferior number NUM.
3372 Kill inferior number NUM.
3376 set spu stop-on-load
3377 show spu stop-on-load
3378 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3380 set spu auto-flush-cache
3381 show spu auto-flush-cache
3382 Control whether to automatically flush the software-managed cache
3383 during Cell/B.E. debugging.
3385 set sh calling-convention
3386 show sh calling-convention
3387 Control the calling convention used when calling SH target functions.
3390 show debug timestamp
3391 Control display of timestamps with GDB debugging output.
3393 set disassemble-next-line
3394 show disassemble-next-line
3395 Control display of disassembled source lines or instructions when
3398 set remote noack-packet
3399 show remote noack-packet
3400 Set/show the use of remote protocol QStartNoAckMode packet. See above
3401 under "New remote packets."
3403 set remote query-attached-packet
3404 show remote query-attached-packet
3405 Control use of remote protocol `qAttached' (query-attached) packet.
3407 set remote read-siginfo-object
3408 show remote read-siginfo-object
3409 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3412 set remote write-siginfo-object
3413 show remote write-siginfo-object
3414 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3417 set remote reverse-continue
3418 show remote reverse-continue
3419 Control use of remote protocol 'bc' (reverse-continue) packet.
3421 set remote reverse-step
3422 show remote reverse-step
3423 Control use of remote protocol 'bs' (reverse-step) packet.
3425 set displaced-stepping
3426 show displaced-stepping
3427 Control displaced stepping mode. Displaced stepping is a way to
3428 single-step over breakpoints without removing them from the debuggee.
3429 Also known as "out-of-line single-stepping".
3432 show debug displaced
3433 Control display of debugging info for displaced stepping.
3435 maint set internal-error
3436 maint show internal-error
3437 Control what GDB does when an internal error is detected.
3439 maint set internal-warning
3440 maint show internal-warning
3441 Control what GDB does when an internal warning is detected.
3446 Use a wrapper program to launch programs for debugging.
3448 set multiple-symbols (all|ask|cancel)
3449 show multiple-symbols
3450 The value of this variable can be changed to adjust the debugger behavior
3451 when an expression or a breakpoint location contains an ambiguous symbol
3452 name (an overloaded function name, for instance).
3454 set breakpoint always-inserted
3455 show breakpoint always-inserted
3456 Keep breakpoints always inserted in the target, as opposed to inserting
3457 them when resuming the target, and removing them when the target stops.
3458 This option can improve debugger performance on slow remote targets.
3460 set arm fallback-mode (arm|thumb|auto)
3461 show arm fallback-mode
3462 set arm force-mode (arm|thumb|auto)
3464 These commands control how ARM GDB determines whether instructions
3465 are ARM or Thumb. The default for both settings is auto, which uses
3466 the current CPSR value for instructions without symbols; previous
3467 versions of GDB behaved as if "set arm fallback-mode arm".
3469 set disable-randomization
3470 show disable-randomization
3471 Standalone programs run with the virtual address space randomization enabled
3472 by default on some platforms. This option keeps the addresses stable across
3473 multiple debugging sessions.
3477 Control whether other threads are stopped or not when some thread hits
3482 Requests that asynchronous execution is enabled in the target, if available.
3483 In this case, it's possible to resume target in the background, and interact
3484 with GDB while the target is running. "show target-async" displays the
3485 current state of asynchronous execution of the target.
3487 set target-wide-charset
3488 show target-wide-charset
3489 The target-wide-charset is the name of the character set that GDB
3490 uses when printing characters whose type is wchar_t.
3492 set tcp auto-retry (on|off)
3494 set tcp connect-timeout
3495 show tcp connect-timeout
3496 These commands allow GDB to retry failed TCP connections to a remote stub
3497 with a specified timeout period; this is useful if the stub is launched
3498 in parallel with GDB but may not be ready to accept connections immediately.
3500 set libthread-db-search-path
3501 show libthread-db-search-path
3502 Control list of directories which GDB will search for appropriate
3505 set schedule-multiple (on|off)
3506 show schedule-multiple
3507 Allow GDB to resume all threads of all processes or only threads of
3508 the current process.
3512 Use more aggressive caching for accesses to the stack. This improves
3513 performance of remote debugging (particularly backtraces) without
3514 affecting correctness.
3516 set interactive-mode (on|off|auto)
3517 show interactive-mode
3518 Control whether GDB runs in interactive mode (on) or not (off).
3519 When in interactive mode, GDB waits for the user to answer all
3520 queries. Otherwise, GDB does not wait and assumes the default
3521 answer. When set to auto (the default), GDB determines which
3522 mode to use based on the stdin settings.
3527 For program forks, this is replaced by the new more generic `info
3528 inferiors' command. To list checkpoints, you can still use the
3529 `info checkpoints' command, which was an alias for the `info forks'
3533 Replaced by the new `inferior' command. To switch between
3534 checkpoints, you can still use the `restart' command, which was an
3535 alias for the `fork' command.
3538 This is removed, since some targets don't have a notion of
3539 processes. To switch between processes, you can still use the
3540 `inferior' command using GDB's own inferior number.
3543 For program forks, this is replaced by the new more generic `kill
3544 inferior' command. To delete a checkpoint, you can still use the
3545 `delete checkpoint' command, which was an alias for the `delete
3549 For program forks, this is replaced by the new more generic `detach
3550 inferior' command. To detach a checkpoint, you can still use the
3551 `detach checkpoint' command, which was an alias for the `detach
3554 * New native configurations
3556 x86/x86_64 Darwin i[34567]86-*-darwin*
3558 x86_64 MinGW x86_64-*-mingw*
3562 Lattice Mico32 lm32-*
3563 x86 DICOS i[34567]86-*-dicos*
3564 x86_64 DICOS x86_64-*-dicos*
3567 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3568 (mingw32ce) debugging.
3574 These commands were actually not implemented on any target.
3576 *** Changes in GDB 6.8
3578 * New native configurations
3580 NetBSD/hppa hppa*-*netbsd*
3581 Xtensa GNU/Linux xtensa*-*-linux*
3585 NetBSD/hppa hppa*-*-netbsd*
3586 Xtensa GNU/Lunux xtensa*-*-linux*
3588 * Change in command line behavior -- corefiles vs. process ids.
3590 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3591 attaching to process NUMBER fails, GDB no longer attempts to open a
3592 core file named NUMBER. Attaching to a program using the -c option
3593 is no longer supported. Instead, use the '-p' or '--pid' options.
3595 * GDB can now be built as a native debugger for debugging Windows x86
3596 (mingw32) Portable Executable (PE) programs.
3598 * Pending breakpoints no longer change their number when their address
3601 * GDB now supports breakpoints with multiple locations,
3602 including breakpoints on C++ constructors, inside C++ templates,
3603 and in inlined functions.
3605 * GDB's ability to debug optimized code has been improved. GDB more
3606 accurately identifies function bodies and lexical blocks that occupy
3607 more than one contiguous range of addresses.
3609 * Target descriptions can now describe registers for PowerPC.
3611 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3612 registers on PowerPC targets.
3614 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3615 targets even when the libthread_db library is not available.
3617 * The GDB remote stub, gdbserver, now supports the new file transfer
3618 commands (remote put, remote get, and remote delete).
3620 * The GDB remote stub, gdbserver, now supports run and attach in
3621 extended-remote mode.
3623 * hppa*64*-*-hpux11* target broken
3624 The debugger is unable to start a program and fails with the following
3625 error: "Error trying to get information about dynamic linker".
3626 The gdb-6.7 release is also affected.
3628 * GDB now supports the --enable-targets= configure option to allow
3629 building a single GDB executable that supports multiple remote
3630 target architectures.
3632 * GDB now supports debugging C and C++ programs which use the
3633 Decimal Floating Point extension. In addition, the PowerPC target
3634 now has a set of pseudo-registers to inspect decimal float values
3635 stored in two consecutive float registers.
3637 * The -break-insert MI command can optionally create pending
3640 * Improved support for debugging Ada
3641 Many improvements to the Ada language support have been made. These
3643 - Better support for Ada2005 interface types
3644 - Improved handling of arrays and slices in general
3645 - Better support for Taft-amendment types
3646 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3648 - Improved command completion in Ada
3651 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3656 set print frame-arguments (all|scalars|none)
3657 show print frame-arguments
3658 The value of this variable can be changed to control which argument
3659 values should be printed by the debugger when displaying a frame.
3664 Transfer files to and from a remote target, and delete remote files.
3671 Transfer files to and from a remote target, and delete remote files.
3673 * New remote packets
3680 Open, close, read, write, and delete files on the remote system.
3683 Attach to an existing process on the remote system, in extended-remote
3687 Run a new process on the remote system, in extended-remote mode.
3689 *** Changes in GDB 6.7
3691 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3692 bfd, libiberty and opcodes, as revealed by static analysis donated by
3693 Coverity, Inc. (http://scan.coverity.com).
3695 * When looking up multiply-defined global symbols, GDB will now prefer the
3696 symbol definition in the current shared library if it was built using the
3697 -Bsymbolic linker option.
3699 * When the Text User Interface (TUI) is not configured, GDB will now
3700 recognize the -tui command-line option and print a message that the TUI
3703 * The GDB remote stub, gdbserver, now has lower overhead for high
3704 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3706 * GDB for MIPS targets now autodetects whether a remote target provides
3707 32-bit or 64-bit register values.
3709 * Support for C++ member pointers has been improved.
3711 * GDB now understands XML target descriptions, which specify the
3712 target's overall architecture. GDB can read a description from
3713 a local file or over the remote serial protocol.
3715 * Vectors of single-byte data use a new integer type which is not
3716 automatically displayed as character or string data.
3718 * The /s format now works with the print command. It displays
3719 arrays of single-byte integers and pointers to single-byte integers
3722 * Target descriptions can now describe target-specific registers,
3723 for architectures which have implemented the support (currently
3724 only ARM, M68K, and MIPS).
3726 * GDB and the GDB remote stub, gdbserver, now support the XScale
3729 * The GDB remote stub, gdbserver, has been updated to support
3730 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3731 has been rewritten to use the standard GDB remote protocol.
3733 * GDB can now step into C++ functions which are called through thunks.
3735 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3737 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3738 layout. It also supports a TextSeg= and DataSeg= response when only
3739 segment base addresses (rather than offsets) are available.
3741 * The /i format now outputs any trailing branch delay slot instructions
3742 immediately following the last instruction within the count specified.
3744 * The GDB remote protocol "T" stop reply packet now supports a
3745 "library" response. Combined with the new "qXfer:libraries:read"
3746 packet, this response allows GDB to debug shared libraries on targets
3747 where the operating system manages the list of loaded libraries (e.g.
3748 Windows and SymbianOS).
3750 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3751 (DLLs) on Windows and Windows CE targets.
3753 * GDB now supports a faster verification that a .debug file matches its binary
3754 according to its build-id signature, if the signature is present.
3760 Enable or disable hardware flow control (RTS/CTS) on the serial port
3761 when debugging using remote targets.
3763 set mem inaccessible-by-default
3764 show mem inaccessible-by-default
3765 If the target supplies a memory map, for instance via the remote
3766 protocol's "qXfer:memory-map:read" packet, setting this variable
3767 prevents GDB from accessing memory outside the memory map. This
3768 is useful for targets with memory mapped registers or which react
3769 badly to accesses of unmapped address space.
3771 set breakpoint auto-hw
3772 show breakpoint auto-hw
3773 If the target supplies a memory map, for instance via the remote
3774 protocol's "qXfer:memory-map:read" packet, setting this variable
3775 lets GDB use hardware breakpoints automatically for memory regions
3776 where it can not use software breakpoints. This covers both the
3777 "break" command and internal breakpoints used for other commands
3778 including "next" and "finish".
3781 catch exception unhandled
3782 Stop the program execution when Ada exceptions are raised.
3785 Stop the program execution when an Ada assertion failed.
3789 Set an alternate system root for target files. This is a more
3790 general version of "set solib-absolute-prefix", which is now
3791 an alias to "set sysroot".
3794 Provide extended SPU facility status information. This set of
3795 commands is available only when debugging the Cell/B.E. SPU
3798 * New native configurations
3800 OpenBSD/sh sh*-*openbsd*
3803 unset tdesc filename
3805 Use the specified local file as an XML target description, and do
3806 not query the target for its built-in description.
3810 OpenBSD/sh sh*-*-openbsd*
3811 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3812 Toshiba Media Processor mep-elf
3814 * New remote packets
3817 Ignore the specified signals; pass them directly to the debugged program
3818 without stopping other threads or reporting them to GDB.
3820 qXfer:features:read:
3821 Read an XML target description from the target, which describes its
3826 Read or write contents of an spufs file on the target system. These
3827 packets are available only on the Cell/B.E. SPU architecture.
3829 qXfer:libraries:read:
3830 Report the loaded shared libraries. Combined with new "T" packet
3831 response, this packet allows GDB to debug shared libraries on
3832 targets where the operating system manages the list of loaded
3833 libraries (e.g. Windows and SymbianOS).
3837 Support for these obsolete configurations has been removed.
3845 i[34567]86-*-lynxos*
3846 i[34567]86-*-netware*
3847 i[34567]86-*-sco3.2v5*
3848 i[34567]86-*-sco3.2v4*
3850 i[34567]86-*-sysv4.2*
3853 i[34567]86-*-unixware2*
3854 i[34567]86-*-unixware*
3863 * Other removed features
3870 Various m68k-only ROM monitors.
3877 Various Renesas ROM monitors and debugging interfaces for SH and
3882 Support for a Macraigor serial interface to on-chip debugging.
3883 GDB does not directly support the newer parallel or USB
3888 A debug information format. The predecessor to DWARF 2 and
3889 DWARF 3, which are still supported.
3891 Support for the HP aCC compiler on HP-UX/PA-RISC
3893 SOM-encapsulated symbolic debugging information, automatic
3894 invocation of pxdb, and the aCC custom C++ ABI. This does not
3895 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3896 with aCC can still be debugged on an assembly level.
3898 MIPS ".pdr" sections
3900 A MIPS-specific format used to describe stack frame layout
3901 in debugging information.
3905 GDB could work with an older version of Guile to debug
3906 the interpreter and Scheme programs running in it.
3908 set mips stack-arg-size
3909 set mips saved-gpreg-size
3911 Use "set mips abi" to control parameter passing for MIPS.
3913 *** Changes in GDB 6.6
3918 Cell Broadband Engine SPU spu-elf
3920 * GDB can now be configured as a cross-debugger targeting native Windows
3921 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3922 running on a Windows system over TCP/IP to debug Windows programs.
3924 * The GDB remote stub, gdbserver, has been updated to support Windows and
3925 Cygwin debugging. Both single-threaded and multi-threaded programs are
3928 * The "set trust-readonly-sections" command works again. This command was
3929 broken in GDB 6.3, 6.4, and 6.5.
3931 * The "load" command now supports writing to flash memory, if the remote
3932 stub provides the required support.
3934 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3935 longer requires symbolic debug information (e.g. DWARF-2).
3940 unset substitute-path
3941 show substitute-path
3942 Manage a list of substitution rules that GDB uses to rewrite the name
3943 of the directories where the sources are located. This can be useful
3944 for instance when the sources were moved to a different location
3945 between compilation and debugging.
3949 Print each CLI command as it is executed. Each command is prefixed with
3950 a number of `+' symbols representing the nesting depth.
3951 The source command now has a `-v' option to enable the same feature.
3955 The ARM Demon monitor support (RDP protocol, "target rdp").
3957 Kernel Object Display, an embedded debugging feature which only worked with
3958 an obsolete version of Cisco IOS.
3960 The 'set download-write-size' and 'show download-write-size' commands.
3962 * New remote packets
3965 Tell a stub about GDB client features, and request remote target features.
3966 The first feature implemented is PacketSize, which allows the target to
3967 specify the size of packets it can handle - to minimize the number of
3968 packets required and improve performance when connected to a remote
3972 Fetch an OS auxilliary vector from the remote stub. This packet is a
3973 more efficient replacement for qPart:auxv:read.
3975 qXfer:memory-map:read:
3976 Fetch a memory map from the remote stub, including information about
3977 RAM, ROM, and flash memory devices.
3982 Erase and program a flash memory device.
3984 * Removed remote packets
3987 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3988 used it, and only gdbserver implemented it.
3990 *** Changes in GDB 6.5
3994 Renesas M32C/M16C m32c-elf
3996 Morpho Technologies ms1 ms1-elf
4000 init-if-undefined Initialize a convenience variable, but
4001 only if it doesn't already have a value.
4003 The following commands are presently only implemented for native GNU/Linux:
4005 checkpoint Save a snapshot of the program state.
4007 restart <n> Return the program state to a
4008 previously saved state.
4010 info checkpoints List currently saved checkpoints.
4012 delete-checkpoint <n> Delete a previously saved checkpoint.
4014 set|show detach-on-fork Tell gdb whether to detach from a newly
4015 forked process, or to keep debugging it.
4017 info forks List forks of the user program that
4018 are available to be debugged.
4020 fork <n> Switch to debugging one of several
4021 forks of the user program that are
4022 available to be debugged.
4024 delete-fork <n> Delete a fork from the list of forks
4025 that are available to be debugged (and
4026 kill the forked process).
4028 detach-fork <n> Delete a fork from the list of forks
4029 that are available to be debugged (and
4030 allow the process to continue).
4034 Morpho Technologies ms2 ms1-elf
4036 * Improved Windows host support
4038 GDB now builds as a cross debugger hosted on i686-mingw32, including
4039 native console support, and remote communications using either
4040 network sockets or serial ports.
4042 * Improved Modula-2 language support
4044 GDB can now print most types in the Modula-2 syntax. This includes:
4045 basic types, set types, record types, enumerated types, range types,
4046 pointer types and ARRAY types. Procedure var parameters are correctly
4047 printed and hexadecimal addresses and character constants are also
4048 written in the Modula-2 syntax. Best results can be obtained by using
4049 GNU Modula-2 together with the -gdwarf-2 command line option.
4053 The ARM rdi-share module.
4055 The Netware NLM debug server.
4057 *** Changes in GDB 6.4
4059 * New native configurations
4061 OpenBSD/arm arm*-*-openbsd*
4062 OpenBSD/mips64 mips64-*-openbsd*
4066 Morpho Technologies ms1 ms1-elf
4068 * New command line options
4070 --batch-silent As for --batch, but totally silent.
4071 --return-child-result The debugger will exist with the same value
4072 the child (debugged) program exited with.
4073 --eval-command COMMAND, -ex COMMAND
4074 Execute a single GDB CLI command. This may be
4075 specified multiple times and in conjunction
4076 with the --command (-x) option.
4078 * Deprecated commands removed
4080 The following commands, that were deprecated in 2000, have been
4084 set|show arm disassembly-flavor set|show arm disassembler
4085 othernames set arm disassembler
4086 set|show remotedebug set|show debug remote
4087 set|show archdebug set|show debug arch
4088 set|show eventdebug set|show debug event
4091 * New BSD user-level threads support
4093 It is now possible to debug programs using the user-level threads
4094 library on OpenBSD and FreeBSD. Currently supported (target)
4097 FreeBSD/amd64 x86_64-*-freebsd*
4098 FreeBSD/i386 i386-*-freebsd*
4099 OpenBSD/i386 i386-*-openbsd*
4101 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4102 are not yet supported.
4104 * New support for Matsushita MN10300 w/sim added
4105 (Work in progress). mn10300-elf.
4107 * REMOVED configurations and files
4109 VxWorks and the XDR protocol *-*-vxworks
4110 Motorola MCORE mcore-*-*
4111 National Semiconductor NS32000 ns32k-*-*
4113 * New "set print array-indexes" command
4115 After turning this setting "on", GDB prints the index of each element
4116 when displaying arrays. The default is "off" to preserve the previous
4119 * VAX floating point support
4121 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4123 * User-defined command support
4125 In addition to using $arg0..$arg9 for argument passing, it is now possible
4126 to use $argc to determine now many arguments have been passed. See the
4127 section on user-defined commands in the user manual for more information.
4129 *** Changes in GDB 6.3:
4131 * New command line option
4133 GDB now accepts -l followed by a number to set the timeout for remote
4136 * GDB works with GCC -feliminate-dwarf2-dups
4138 GDB now supports a more compact representation of DWARF-2 debug
4139 information using DW_FORM_ref_addr references. These are produced
4140 by GCC with the option -feliminate-dwarf2-dups and also by some
4141 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4142 to use -feliminate-dwarf2-dups.
4144 * Internationalization
4146 When supported by the host system, GDB will be built with
4147 internationalization (libintl). The task of marking up the sources is
4148 continued, we're looking forward to our first translation.
4152 Initial support for debugging programs compiled with the GNAT
4153 implementation of the Ada programming language has been integrated
4154 into GDB. In this release, support is limited to expression evaluation.
4156 * New native configurations
4158 GNU/Linux/m32r m32r-*-linux-gnu
4162 GDB's remote protocol now includes support for the 'p' packet. This
4163 packet is used to fetch individual registers from a remote inferior.
4165 * END-OF-LIFE registers[] compatibility module
4167 GDB's internal register infrastructure has been completely rewritten.
4168 The new infrastructure making possible the implementation of key new
4169 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4172 GDB 6.3 will be the last release to include the the registers[]
4173 compatibility module that allowed out-of-date configurations to
4174 continue to work. This change directly impacts the following
4184 powerpc bdm protocol
4186 Unless there is activity to revive these configurations, they will be
4187 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4189 * OBSOLETE configurations and files
4191 Configurations that have been declared obsolete in this release have
4192 been commented out. Unless there is activity to revive these
4193 configurations, the next release of GDB will have their sources
4194 permanently REMOVED.
4203 *** Changes in GDB 6.2.1:
4205 * MIPS `break main; run' gave an heuristic-fence-post warning
4207 When attempting to run even a simple program, a warning about
4208 heuristic-fence-post being hit would be reported. This problem has
4211 * MIPS IRIX 'long double' crashed GDB
4213 When examining a long double variable, GDB would get a segmentation
4214 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4215 IRIX long double values).
4219 A bug in the VAX stack code was causing problems with the "next"
4220 command. This problem has been fixed.
4222 *** Changes in GDB 6.2:
4224 * Fix for ``many threads''
4226 On GNU/Linux systems that use the NPTL threads library, a program
4227 rapidly creating and deleting threads would confuse GDB leading to the
4230 ptrace: No such process.
4231 thread_db_get_info: cannot get thread info: generic error
4233 This problem has been fixed.
4235 * "-async" and "-noasync" options removed.
4237 Support for the broken "-noasync" option has been removed (it caused
4240 * New ``start'' command.
4242 This command runs the program until the begining of the main procedure.
4244 * New BSD Kernel Data Access Library (libkvm) interface
4246 Using ``target kvm'' it is now possible to debug kernel core dumps and
4247 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4248 platforms. Currently supported (native-only) configurations are:
4250 FreeBSD/amd64 x86_64-*-freebsd*
4251 FreeBSD/i386 i?86-*-freebsd*
4252 NetBSD/i386 i?86-*-netbsd*
4253 NetBSD/m68k m68*-*-netbsd*
4254 NetBSD/sparc sparc-*-netbsd*
4255 OpenBSD/amd64 x86_64-*-openbsd*
4256 OpenBSD/i386 i?86-*-openbsd*
4257 OpenBSD/m68k m68*-openbsd*
4258 OpenBSD/sparc sparc-*-openbsd*
4260 * Signal trampoline code overhauled
4262 Many generic problems with GDB's signal handling code have been fixed.
4263 These include: backtraces through non-contiguous stacks; recognition
4264 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4265 call; backtrace through a signal trampoline; step into and out of
4266 signal handlers; and single-stepping in the signal trampoline.
4268 Please note that kernel bugs are a limiting factor here. These
4269 features have been shown to work on an s390 GNU/Linux system that
4270 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4272 * Cygwin support for DWARF 2 added.
4274 * New native configurations
4276 GNU/Linux/hppa hppa*-*-linux*
4277 OpenBSD/hppa hppa*-*-openbsd*
4278 OpenBSD/m68k m68*-*-openbsd*
4279 OpenBSD/m88k m88*-*-openbsd*
4280 OpenBSD/powerpc powerpc-*-openbsd*
4281 NetBSD/vax vax-*-netbsd*
4282 OpenBSD/vax vax-*-openbsd*
4284 * END-OF-LIFE frame compatibility module
4286 GDB's internal frame infrastructure has been completely rewritten.
4287 The new infrastructure making it possible to support key new features
4288 including DWARF 2 Call Frame Information. To aid in the task of
4289 migrating old configurations to this new infrastructure, a
4290 compatibility module, that allowed old configurations to continue to
4291 work, was also included.
4293 GDB 6.2 will be the last release to include this frame compatibility
4294 module. This change directly impacts the following configurations:
4304 Unless there is activity to revive these configurations, they will be
4305 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4307 * REMOVED configurations and files
4309 Sun 3, running SunOS 3 m68*-*-sunos3*
4310 Sun 3, running SunOS 4 m68*-*-sunos4*
4311 Sun 2, running SunOS 3 m68000-*-sunos3*
4312 Sun 2, running SunOS 4 m68000-*-sunos4*
4313 Motorola 680x0 running LynxOS m68*-*-lynxos*
4314 AT&T 3b1/Unix pc m68*-att-*
4315 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4316 decstation mips-dec-* mips-little-*
4317 riscos mips-*-riscos* mips-*-sysv*
4318 sonymips mips-sony-*
4319 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4321 *** Changes in GDB 6.1.1:
4323 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4325 The TUI (Text-mode User Interface) is now built as part of a default
4326 GDB configuration. It is enabled by either selecting the TUI with the
4327 command line option "-i=tui" or by running the separate "gdbtui"
4328 program. For more information on the TUI, see the manual "Debugging
4331 * Pending breakpoint support (also included in GDB 6.1)
4333 Support has been added to allow you to specify breakpoints in shared
4334 libraries that have not yet been loaded. If a breakpoint location
4335 cannot be found, and the "breakpoint pending" option is set to auto,
4336 GDB queries you if you wish to make the breakpoint pending on a future
4337 shared-library load. If and when GDB resolves the breakpoint symbol,
4338 the pending breakpoint is removed as one or more regular breakpoints
4341 Pending breakpoints are very useful for GCJ Java debugging.
4343 * Fixed ISO-C build problems
4345 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4346 non ISO-C code that stopped them being built using a more strict ISO-C
4347 compiler (e.g., IBM's C compiler).
4349 * Fixed build problem on IRIX 5
4351 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4352 wasn't able to compile compile on an IRIX 5 system.
4354 * Added execute permission to gdb/gdbserver/configure
4356 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4357 permission. This bug would cause configure to fail on a number of
4358 systems (Solaris, IRIX). Ref: server/519.
4360 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4362 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4363 has been updated to use constant array sizes.
4365 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4367 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4368 its generated DWARF Call Frame Info. This encoding was causing GDB to
4369 panic, that panic has been fixed. Ref: gdb/1628.
4371 * Fixed a problem when examining parameters in shared library code.
4373 When examining parameters in optimized shared library code generated
4374 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4375 not available''. GDB now correctly displays the variable's value.
4377 *** Changes in GDB 6.1:
4379 * Removed --with-mmalloc
4381 Support for the mmalloc memory manager has been removed, as it
4382 conflicted with the internal gdb byte cache.
4384 * Changes in AMD64 configurations
4386 The AMD64 target now includes the %cs and %ss registers. As a result
4387 the AMD64 remote protocol has changed; this affects the floating-point
4388 and SSE registers. If you rely on those registers for your debugging,
4389 you should upgrade gdbserver on the remote side.
4391 * Revised SPARC target
4393 The SPARC target has been completely revised, incorporating the
4394 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4395 support for LynxOS and SunOS 4 has been dropped. Calling functions
4396 from within GDB on operating systems with a non-executable stack
4397 (Solaris, OpenBSD) now works.
4401 GDB has a new C++ demangler which does a better job on the mangled
4402 names generated by current versions of g++. It also runs faster, so
4403 with this and other changes gdb should now start faster on large C++
4406 * DWARF 2 Location Expressions
4408 GDB support for location expressions has been extended to support function
4409 arguments and frame bases. Older versions of GDB could crash when they
4412 * C++ nested types and namespaces
4414 GDB's support for nested types and namespaces in C++ has been
4415 improved, especially if you use the DWARF 2 debugging format. (This
4416 is the default for recent versions of GCC on most platforms.)
4417 Specifically, if you have a class "Inner" defined within a class or
4418 namespace "Outer", then GDB realizes that the class's name is
4419 "Outer::Inner", not simply "Inner". This should greatly reduce the
4420 frequency of complaints about not finding RTTI symbols. In addition,
4421 if you are stopped at inside of a function defined within a namespace,
4422 GDB modifies its name lookup accordingly.
4424 * New native configurations
4426 NetBSD/amd64 x86_64-*-netbsd*
4427 OpenBSD/amd64 x86_64-*-openbsd*
4428 OpenBSD/alpha alpha*-*-openbsd*
4429 OpenBSD/sparc sparc-*-openbsd*
4430 OpenBSD/sparc64 sparc64-*-openbsd*
4432 * New debugging protocols
4434 M32R with SDI protocol m32r-*-elf*
4436 * "set prompt-escape-char" command deleted.
4438 The command "set prompt-escape-char" has been deleted. This command,
4439 and its very obscure effet on GDB's prompt, was never documented,
4440 tested, nor mentioned in the NEWS file.
4442 * OBSOLETE configurations and files
4444 Configurations that have been declared obsolete in this release have
4445 been commented out. Unless there is activity to revive these
4446 configurations, the next release of GDB will have their sources
4447 permanently REMOVED.
4449 Sun 3, running SunOS 3 m68*-*-sunos3*
4450 Sun 3, running SunOS 4 m68*-*-sunos4*
4451 Sun 2, running SunOS 3 m68000-*-sunos3*
4452 Sun 2, running SunOS 4 m68000-*-sunos4*
4453 Motorola 680x0 running LynxOS m68*-*-lynxos*
4454 AT&T 3b1/Unix pc m68*-att-*
4455 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4456 decstation mips-dec-* mips-little-*
4457 riscos mips-*-riscos* mips-*-sysv*
4458 sonymips mips-sony-*
4459 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4461 * REMOVED configurations and files
4463 SGI Irix-4.x mips-sgi-irix4 or iris4
4464 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4465 Z8000 simulator z8k-zilog-none or z8ksim
4466 Matsushita MN10200 w/simulator mn10200-*-*
4467 H8/500 simulator h8500-hitachi-hms or h8500hms
4468 HP/PA running BSD hppa*-*-bsd*
4469 HP/PA running OSF/1 hppa*-*-osf*
4470 HP/PA Pro target hppa*-*-pro*
4471 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4472 386BSD i[3456]86-*-bsd*
4473 Sequent family i[3456]86-sequent-sysv4*
4474 i[3456]86-sequent-sysv*
4475 i[3456]86-sequent-bsd*
4476 SPARC running LynxOS sparc-*-lynxos*
4477 SPARC running SunOS 4 sparc-*-sunos4*
4478 Tsqware Sparclet sparclet-*-*
4479 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4481 *** Changes in GDB 6.0:
4485 Support for debugging the Objective-C programming language has been
4486 integrated into GDB.
4488 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4490 DWARF 2's Call Frame Information makes available compiler generated
4491 information that more exactly describes the program's run-time stack.
4492 By using this information, GDB is able to provide more robust stack
4495 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4496 have been updated to use a new backtrace mechanism which includes
4497 DWARF 2 CFI support.
4501 GDB's remote protocol has been extended to include support for hosted
4502 file I/O (where the remote target uses GDB's file system). See GDB's
4503 remote protocol documentation for details.
4505 * All targets using the new architecture framework.
4507 All of GDB's targets have been updated to use the new internal
4508 architecture framework. The way is now open for future GDB releases
4509 to include cross-architecture native debugging support (i386 on amd64,
4512 * GNU/Linux's Thread Local Storage (TLS)
4514 GDB now includes support for for the GNU/Linux implementation of
4515 per-thread variables.
4517 * GNU/Linux's Native POSIX Thread Library (NPTL)
4519 GDB's thread code has been updated to work with either the new
4520 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4522 * Separate debug info.
4524 GDB, in conjunction with BINUTILS, now supports a mechanism for
4525 automatically loading debug information from a separate file. Instead
4526 of shipping full debug and non-debug versions of system libraries,
4527 system integrators can now instead ship just the stripped libraries
4528 and optional debug files.
4530 * DWARF 2 Location Expressions
4532 DWARF 2 Location Expressions allow the compiler to more completely
4533 describe the location of variables (even in optimized code) to the
4536 GDB now includes preliminary support for location expressions (support
4537 for DW_OP_piece is still missing).
4541 A number of long standing bugs that caused GDB to die while starting a
4542 Java application have been fixed. GDB's Java support is now
4543 considered "useable".
4545 * GNU/Linux support for fork, vfork, and exec.
4547 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4548 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4551 * GDB supports logging output to a file
4553 There are two new commands, "set logging" and "show logging", which can be
4554 used to capture GDB's output to a file.
4556 * The meaning of "detach" has changed for gdbserver
4558 The "detach" command will now resume the application, as documented. To
4559 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4562 * d10v, m68hc11 `regs' command deprecated
4564 The `info registers' command has been updated so that it displays the
4565 registers using a format identical to the old `regs' command.
4569 A new command, "maint set profile on/off", has been added. This command can
4570 be used to enable or disable profiling while running GDB, to profile a
4571 session or a set of commands. In addition there is a new configure switch,
4572 "--enable-profiling", which will cause GDB to be compiled with profiling
4573 data, for more informative profiling results.
4575 * Default MI syntax changed to "mi2".
4577 The default MI (machine interface) syntax, enabled by the command line
4578 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4579 "mi1", can be enabled by specifying the option "-i=mi1".
4581 Support for the original "mi0" syntax (included in GDB 5.0) has been
4584 Fix for gdb/192: removed extraneous space when displaying frame level.
4585 Fix for gdb/672: update changelist is now output in mi list format.
4586 Fix for gdb/702: a -var-assign that updates the value now shows up
4587 in a subsequent -var-update.
4589 * New native configurations.
4591 FreeBSD/amd64 x86_64-*-freebsd*
4593 * Multi-arched targets.
4595 HP/PA HPUX11 hppa*-*-hpux*
4596 Renesas M32R/D w/simulator m32r-*-elf*
4598 * OBSOLETE configurations and files
4600 Configurations that have been declared obsolete in this release have
4601 been commented out. Unless there is activity to revive these
4602 configurations, the next release of GDB will have their sources
4603 permanently REMOVED.
4605 Z8000 simulator z8k-zilog-none or z8ksim
4606 Matsushita MN10200 w/simulator mn10200-*-*
4607 H8/500 simulator h8500-hitachi-hms or h8500hms
4608 HP/PA running BSD hppa*-*-bsd*
4609 HP/PA running OSF/1 hppa*-*-osf*
4610 HP/PA Pro target hppa*-*-pro*
4611 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4612 Sequent family i[3456]86-sequent-sysv4*
4613 i[3456]86-sequent-sysv*
4614 i[3456]86-sequent-bsd*
4615 Tsqware Sparclet sparclet-*-*
4616 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4618 * REMOVED configurations and files
4621 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4622 IBM AIX PS/2 i[3456]86-*-aix
4623 i386 running Mach 3.0 i[3456]86-*-mach3*
4624 i386 running Mach i[3456]86-*-mach*
4625 i386 running OSF/1 i[3456]86-*osf1mk*
4626 HP/Apollo 68k Family m68*-apollo*-sysv*,
4628 m68*-hp-bsd*, m68*-hp-hpux*
4629 Argonaut Risc Chip (ARC) arc-*-*
4630 Mitsubishi D30V d30v-*-*
4631 Fujitsu FR30 fr30-*-elf*
4632 OS/9000 i[34]86-*-os9k
4633 I960 with MON960 i960-*-coff
4635 * MIPS $fp behavior changed
4637 The convenience variable $fp, for the MIPS, now consistently returns
4638 the address of the current frame's base. Previously, depending on the
4639 context, $fp could refer to either $sp or the current frame's base
4640 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4641 The GNU Source-Level Debugger''.
4643 *** Changes in GDB 5.3:
4645 * GNU/Linux shared library multi-threaded performance improved.
4647 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4648 `/proc', in preference to `ptrace' for memory reads. This may result
4649 in an improvement in the start-up time of multi-threaded, shared
4650 library applications when run under GDB. One GDB user writes: ``loads
4651 shared libs like mad''.
4653 * ``gdbserver'' now supports multi-threaded applications on some targets
4655 Support for debugging multi-threaded applications which use
4656 the GNU/Linux LinuxThreads package has been added for
4657 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4658 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4660 * GDB now supports C/C++ preprocessor macros.
4662 GDB now expands preprocessor macro invocations in C/C++ expressions,
4663 and provides various commands for showing macro definitions and how
4666 The new command `macro expand EXPRESSION' expands any macro
4667 invocations in expression, and shows the result.
4669 The new command `show macro MACRO-NAME' shows the definition of the
4670 macro named MACRO-NAME, and where it was defined.
4672 Most compilers don't include information about macros in the debugging
4673 information by default. In GCC 3.1, for example, you need to compile
4674 your program with the options `-gdwarf-2 -g3'. If the macro
4675 information is present in the executable, GDB will read it.
4677 * Multi-arched targets.
4679 DEC Alpha (partial) alpha*-*-*
4680 DEC VAX (partial) vax-*-*
4682 National Semiconductor NS32000 (partial) ns32k-*-*
4683 Motorola 68000 (partial) m68k-*-*
4684 Motorola MCORE mcore-*-*
4688 Fujitsu FRV architecture added by Red Hat frv*-*-*
4691 * New native configurations
4693 Alpha NetBSD alpha*-*-netbsd*
4694 SH NetBSD sh*-*-netbsdelf*
4695 MIPS NetBSD mips*-*-netbsd*
4696 UltraSPARC NetBSD sparc64-*-netbsd*
4698 * OBSOLETE configurations and files
4700 Configurations that have been declared obsolete in this release have
4701 been commented out. Unless there is activity to revive these
4702 configurations, the next release of GDB will have their sources
4703 permanently REMOVED.
4705 Mitsubishi D30V d30v-*-*
4706 OS/9000 i[34]86-*-os9k
4707 IBM AIX PS/2 i[3456]86-*-aix
4708 Fujitsu FR30 fr30-*-elf*
4709 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4710 Argonaut Risc Chip (ARC) arc-*-*
4711 i386 running Mach 3.0 i[3456]86-*-mach3*
4712 i386 running Mach i[3456]86-*-mach*
4713 i386 running OSF/1 i[3456]86-*osf1mk*
4714 HP/Apollo 68k Family m68*-apollo*-sysv*,
4716 m68*-hp-bsd*, m68*-hp-hpux*
4717 I960 with MON960 i960-*-coff
4719 * OBSOLETE languages
4721 CHILL, a Pascal like language used by telecommunications companies.
4723 * REMOVED configurations and files
4725 AMD 29k family via UDI a29k-amd-udi, udi29k
4726 A29K VxWorks a29k-*-vxworks
4727 AMD 29000 embedded, using EBMON a29k-none-none
4728 AMD 29000 embedded with COFF a29k-none-coff
4729 AMD 29000 embedded with a.out a29k-none-aout
4731 testsuite/gdb.hp/gdb.threads-hp/ directory
4733 * New command "set max-user-call-depth <nnn>"
4735 This command allows the user to limit the call depth of user-defined
4736 commands. The default is 1024.
4738 * Changes in FreeBSD/i386 native debugging.
4740 Support for the "generate-core-file" has been added.
4742 * New commands "dump", "append", and "restore".
4744 These commands allow data to be copied from target memory
4745 to a bfd-format or binary file (dump and append), and back
4746 from a file into memory (restore).
4748 * Improved "next/step" support on multi-processor Alpha Tru64.
4750 The previous single-step mechanism could cause unpredictable problems,
4751 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4752 of a software single-step mechanism prevents this.
4754 *** Changes in GDB 5.2.1:
4762 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4763 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4764 Fix, by Joel Brobecker imported from mainline.
4766 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4767 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4768 Fix, by Fred Fish, imported from mainline.
4770 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4771 Surprisingly enough, it works now.
4772 By Michal Ludvig, imported from mainline.
4774 i386 hardware watchpoint support:
4775 avoid misses on second run for some targets.
4776 By Pierre Muller, imported from mainline.
4778 *** Changes in GDB 5.2:
4780 * New command "set trust-readonly-sections on[off]".
4782 This command is a hint that tells gdb that read-only sections
4783 really are read-only (ie. that their contents will not change).
4784 In this mode, gdb will go to the object file rather than the
4785 target to read memory from read-only sections (such as ".text").
4786 This can be a significant performance improvement on some
4787 (notably embedded) targets.
4789 * New command "generate-core-file" (or "gcore").
4791 This new gdb command allows the user to drop a core file of the child
4792 process state at any time. So far it's been implemented only for
4793 GNU/Linux and Solaris, but should be relatively easily ported to other
4794 hosts. Argument is core file name (defaults to core.<pid>).
4796 * New command line option
4798 GDB now accepts --pid or -p followed by a process id.
4800 * Change in command line behavior -- corefiles vs. process ids.
4802 There is a subtle behavior in the way in which GDB handles
4803 command line arguments. The first non-flag argument is always
4804 a program to debug, but the second non-flag argument may either
4805 be a corefile or a process id. Previously, GDB would attempt to
4806 open the second argument as a corefile, and if that failed, would
4807 issue a superfluous error message and then attempt to attach it as
4808 a process. Now, if the second argument begins with a non-digit,
4809 it will be treated as a corefile. If it begins with a digit,
4810 GDB will attempt to attach it as a process, and if no such process
4811 is found, will then attempt to open it as a corefile.
4813 * Changes in ARM configurations.
4815 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4816 configuration is fully multi-arch.
4818 * New native configurations
4820 ARM NetBSD arm*-*-netbsd*
4821 x86 OpenBSD i[3456]86-*-openbsd*
4822 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4823 Sparc64 running FreeBSD sparc64-*-freebsd*
4827 Sanyo XStormy16 xstormy16-elf
4829 * OBSOLETE configurations and files
4831 Configurations that have been declared obsolete in this release have
4832 been commented out. Unless there is activity to revive these
4833 configurations, the next release of GDB will have their sources
4834 permanently REMOVED.
4836 AMD 29k family via UDI a29k-amd-udi, udi29k
4837 A29K VxWorks a29k-*-vxworks
4838 AMD 29000 embedded, using EBMON a29k-none-none
4839 AMD 29000 embedded with COFF a29k-none-coff
4840 AMD 29000 embedded with a.out a29k-none-aout
4842 testsuite/gdb.hp/gdb.threads-hp/ directory
4844 * REMOVED configurations and files
4846 TI TMS320C80 tic80-*-*
4848 PowerPC Solaris powerpcle-*-solaris*
4849 PowerPC Windows NT powerpcle-*-cygwin32
4850 PowerPC Netware powerpc-*-netware*
4851 Harris/CXUX m88k m88*-harris-cxux*
4852 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4853 ns32k-utek-sysv* ns32k-utek-*
4854 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4855 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4856 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4857 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4858 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4860 * Changes to command line processing
4862 The new `--args' feature can be used to specify command-line arguments
4863 for the inferior from gdb's command line.
4865 * Changes to key bindings
4867 There is a new `operate-and-get-next' function bound to `C-o'.
4869 *** Changes in GDB 5.1.1
4871 Fix compile problem on DJGPP.
4873 Fix a problem with floating-point registers on the i386 being
4876 Fix to stop GDB crashing on .debug_str debug info.
4878 Numerous documentation fixes.
4880 Numerous testsuite fixes.
4882 *** Changes in GDB 5.1:
4884 * New native configurations
4886 Alpha FreeBSD alpha*-*-freebsd*
4887 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4888 MIPS GNU/Linux mips*-*-linux*
4889 MIPS SGI Irix 6.x mips*-sgi-irix6*
4890 ia64 AIX ia64-*-aix*
4891 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4895 Motorola 68HC11 and 68HC12 m68hc11-elf
4897 UltraSparc running GNU/Linux sparc64-*-linux*
4899 * OBSOLETE configurations and files
4901 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4902 Harris/CXUX m88k m88*-harris-cxux*
4903 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4904 ns32k-utek-sysv* ns32k-utek-*
4905 TI TMS320C80 tic80-*-*
4907 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4908 PowerPC Solaris powerpcle-*-solaris*
4909 PowerPC Windows NT powerpcle-*-cygwin32
4910 PowerPC Netware powerpc-*-netware*
4911 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4912 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4913 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4914 Apple Macintosh (MPW) host N/A
4916 stuff.c (Program to stuff files into a specially prepared space in kdb)
4917 kdb-start.c (Main loop for the standalone kernel debugger)
4919 Configurations that have been declared obsolete in this release have
4920 been commented out. Unless there is activity to revive these
4921 configurations, the next release of GDB will have their sources
4922 permanently REMOVED.
4924 * REMOVED configurations and files
4926 Altos 3068 m68*-altos-*
4927 Convex c1-*-*, c2-*-*
4929 ARM RISCix arm-*-* (as host)
4933 * GDB has been converted to ISO C.
4935 GDB's source code has been converted to ISO C. In particular, the
4936 sources are fully protoized, and rely on standard headers being
4941 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4943 * The MI enabled by default.
4945 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4946 revised and enabled by default. Packages which use GDB as a debugging
4947 engine behind a UI or another front end are encouraged to switch to
4948 using the GDB/MI interface, instead of the old annotations interface
4949 which is now deprecated.
4951 * Support for debugging Pascal programs.
4953 GDB now includes support for debugging Pascal programs. The following
4954 main features are supported:
4956 - Pascal-specific data types such as sets;
4958 - automatic recognition of Pascal sources based on file-name
4961 - Pascal-style display of data types, variables, and functions;
4963 - a Pascal expression parser.
4965 However, some important features are not yet supported.
4967 - Pascal string operations are not supported at all;
4969 - there are some problems with boolean types;
4971 - Pascal type hexadecimal constants are not supported
4972 because they conflict with the internal variables format;
4974 - support for Pascal objects and classes is not full yet;
4976 - unlike Pascal, GDB is case-sensitive for symbol names.
4978 * Changes in completion.
4980 Commands such as `shell', `run' and `set args', which pass arguments
4981 to inferior programs, now complete on file names, similar to what
4982 users expect at the shell prompt.
4984 Commands which accept locations, such as `disassemble', `print',
4985 `breakpoint', `until', etc. now complete on filenames as well as
4986 program symbols. Thus, if you type "break foob TAB", and the source
4987 files linked into the programs include `foobar.c', that file name will
4988 be one of the candidates for completion. However, file names are not
4989 considered for completion after you typed a colon that delimits a file
4990 name from a name of a function in that file, as in "break foo.c:bar".
4992 `set demangle-style' completes on available demangling styles.
4994 * New platform-independent commands:
4996 It is now possible to define a post-hook for a command as well as a
4997 hook that runs before the command. For more details, see the
4998 documentation of `hookpost' in the GDB manual.
5000 * Changes in GNU/Linux native debugging.
5002 Support for debugging multi-threaded programs has been completely
5003 revised for all platforms except m68k and sparc. You can now debug as
5004 many threads as your system allows you to have.
5006 Attach/detach is supported for multi-threaded programs.
5008 Support for SSE registers was added for x86. This doesn't work for
5009 multi-threaded programs though.
5011 * Changes in MIPS configurations.
5013 Multi-arch support is enabled for all MIPS configurations.
5015 GDB can now be built as native debugger on SGI Irix 6.x systems for
5016 debugging n32 executables. (Debugging 64-bit executables is not yet
5019 * Unified support for hardware watchpoints in all x86 configurations.
5021 Most (if not all) native x86 configurations support hardware-assisted
5022 breakpoints and watchpoints in a unified manner. This support
5023 implements debug register sharing between watchpoints, which allows to
5024 put a virtually infinite number of watchpoints on the same address,
5025 and also supports watching regions up to 16 bytes with several debug
5028 The new maintenance command `maintenance show-debug-regs' toggles
5029 debugging print-outs in functions that insert, remove, and test
5030 watchpoints and hardware breakpoints.
5032 * Changes in the DJGPP native configuration.
5034 New command ``info dos sysinfo'' displays assorted information about
5035 the CPU, OS, memory, and DPMI server.
5037 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5038 display information about segment descriptors stored in GDT, LDT, and
5041 New commands ``info dos pde'' and ``info dos pte'' display entries
5042 from Page Directory and Page Tables (for now works with CWSDPMI only).
5043 New command ``info dos address-pte'' displays the Page Table entry for
5044 a given linear address.
5046 GDB can now pass command lines longer than 126 characters to the
5047 program being debugged (requires an update to the libdbg.a library
5048 which is part of the DJGPP development kit).
5050 DWARF2 debug info is now supported.
5052 It is now possible to `step' and `next' through calls to `longjmp'.
5054 * Changes in documentation.
5056 All GDB documentation was converted to GFDL, the GNU Free
5057 Documentation License.
5059 Tracepoints-related commands are now fully documented in the GDB
5062 TUI, the Text-mode User Interface, is now documented in the manual.
5064 Tracepoints-related commands are now fully documented in the GDB
5067 The "GDB Internals" manual now has an index. It also includes
5068 documentation of `ui_out' functions, GDB coding standards, x86
5069 hardware watchpoints, and memory region attributes.
5071 * GDB's version number moved to ``version.in''
5073 The Makefile variable VERSION has been replaced by the file
5074 ``version.in''. People creating GDB distributions should update the
5075 contents of this file.
5079 GUD support is now a standard part of the EMACS distribution.
5081 *** Changes in GDB 5.0:
5083 * Improved support for debugging FP programs on x86 targets
5085 Unified and much-improved support for debugging floating-point
5086 programs on all x86 targets. In particular, ``info float'' now
5087 displays the FP registers in the same format on all x86 targets, with
5088 greater level of detail.
5090 * Improvements and bugfixes in hardware-assisted watchpoints
5092 It is now possible to watch array elements, struct members, and
5093 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5094 on x86 targets no longer erroneously trigger when the address is
5097 * Improvements in the native DJGPP version of GDB
5099 The distribution now includes all the scripts and auxiliary files
5100 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5101 machines ``out of the box''.
5103 The DJGPP version can now debug programs that use signals. It is
5104 possible to catch signals that happened in the debuggee, deliver
5105 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5106 would kill the program being debugged.) Programs that hook hardware
5107 interrupts (keyboard, timer, etc.) can also be debugged.
5109 It is now possible to debug DJGPP programs that redirect their
5110 standard handles or switch them to raw (as opposed to cooked) mode, or
5111 even close them. The command ``run < foo > bar'' works as expected,
5112 and ``info terminal'' reports useful information about the debuggee's
5113 terminal, including raw/cooked mode, redirection, etc.
5115 The DJGPP version now uses termios functions for console I/O, which
5116 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5119 DOS-style file names with drive letters are now fully supported by
5122 It is now possible to debug DJGPP programs that switch their working
5123 directory. It is also possible to rerun the debuggee any number of
5124 times without restarting GDB; thus, you can use the same setup,
5125 breakpoints, etc. for many debugging sessions.
5127 * New native configurations
5129 ARM GNU/Linux arm*-*-linux*
5130 PowerPC GNU/Linux powerpc-*-linux*
5134 Motorola MCore mcore-*-*
5135 x86 VxWorks i[3456]86-*-vxworks*
5136 PowerPC VxWorks powerpc-*-vxworks*
5137 TI TMS320C80 tic80-*-*
5139 * OBSOLETE configurations
5141 Altos 3068 m68*-altos-*
5142 Convex c1-*-*, c2-*-*
5144 ARM RISCix arm-*-* (as host)
5147 Configurations that have been declared obsolete will be commented out,
5148 but the code will be left in place. If there is no activity to revive
5149 these configurations before the next release of GDB, the sources will
5150 be permanently REMOVED.
5152 * Gould support removed
5154 Support for the Gould PowerNode and NP1 has been removed.
5156 * New features for SVR4
5158 On SVR4 native platforms (such as Solaris), if you attach to a process
5159 without first loading a symbol file, GDB will now attempt to locate and
5160 load symbols from the running process's executable file.
5162 * Many C++ enhancements
5164 C++ support has been greatly improved. Overload resolution now works properly
5165 in almost all cases. RTTI support is on the way.
5167 * Remote targets can connect to a sub-program
5169 A popen(3) style serial-device has been added. This device starts a
5170 sub-process (such as a stand-alone simulator) and then communicates
5171 with that. The sub-program to run is specified using the syntax
5172 ``|<program> <args>'' vis:
5174 (gdb) set remotedebug 1
5175 (gdb) target extended-remote |mn10300-elf-sim program-args
5177 * MIPS 64 remote protocol
5179 A long standing bug in the mips64 remote protocol where by GDB
5180 expected certain 32 bit registers (ex SR) to be transfered as 32
5181 instead of 64 bits has been fixed.
5183 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5184 added to provide backward compatibility with older versions of GDB.
5186 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5188 The command ``set remotebinarydownload'' command has been replaced by
5189 ``set remote X-packet''. Other commands in ``set remote'' family
5190 include ``set remote P-packet''.
5192 * Breakpoint commands accept ranges.
5194 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5195 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5196 ``tracepoint passcount'' also accepts a range of tracepoints.
5198 * ``apropos'' command added.
5200 The ``apropos'' command searches through command names and
5201 documentation strings, printing out matches, making it much easier to
5202 try to find a command that does what you are looking for.
5206 A new machine oriented interface (MI) has been added to GDB. This
5207 interface is designed for debug environments running GDB as a separate
5208 process. This is part of the long term libGDB project. See the
5209 "GDB/MI" chapter of the GDB manual for further information. It can be
5210 enabled by configuring with:
5212 .../configure --enable-gdbmi
5214 *** Changes in GDB-4.18:
5216 * New native configurations
5218 HP-UX 10.20 hppa*-*-hpux10.20
5219 HP-UX 11.x hppa*-*-hpux11.0*
5220 M68K GNU/Linux m68*-*-linux*
5224 Fujitsu FR30 fr30-*-elf*
5225 Intel StrongARM strongarm-*-*
5226 Mitsubishi D30V d30v-*-*
5228 * OBSOLETE configurations
5230 Gould PowerNode, NP1 np1-*-*, pn-*-*
5232 Configurations that have been declared obsolete will be commented out,
5233 but the code will be left in place. If there is no activity to revive
5234 these configurations before the next release of GDB, the sources will
5235 be permanently REMOVED.
5239 As a compatibility experiment, GDB's source files buildsym.h and
5240 buildsym.c have been converted to pure standard C, no longer
5241 containing any K&R compatibility code. We believe that all systems in
5242 use today either come with a standard C compiler, or have a GCC port
5243 available. If this is not true, please report the affected
5244 configuration to bug-gdb@gnu.org immediately. See the README file for
5245 information about getting a standard C compiler if you don't have one
5250 GDB now uses readline 2.2.
5252 * set extension-language
5254 You can now control the mapping between filename extensions and source
5255 languages by using the `set extension-language' command. For instance,
5256 you can ask GDB to treat .c files as C++ by saying
5257 set extension-language .c c++
5258 The command `info extensions' lists all of the recognized extensions
5259 and their associated languages.
5261 * Setting processor type for PowerPC and RS/6000
5263 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5264 you can use the `set processor' command to specify what variant of the
5265 PowerPC family you are debugging. The command
5269 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5270 following PowerPC and RS6000 variants:
5272 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5273 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5275 403GC IBM PowerPC 403GC
5276 505 Motorola PowerPC 505
5277 860 Motorola PowerPC 860 or 850
5278 601 Motorola PowerPC 601
5279 602 Motorola PowerPC 602
5280 603 Motorola/IBM PowerPC 603 or 603e
5281 604 Motorola PowerPC 604 or 604e
5282 750 Motorola/IBM PowerPC 750 or 750
5284 At the moment, this command just tells GDB what to name the
5285 special-purpose processor registers. Since almost all the affected
5286 registers are inaccessible to user-level programs, this command is
5287 only useful for remote debugging in its present form.
5291 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5292 more extensive support for HP-UX. Added features include shared
5293 library support, kernel threads and hardware watchpoints for 11.00,
5294 support for HP's ANSI C and C++ compilers, and a compatibility mode
5295 for xdb and dbx commands.
5299 HP's donation includes the new concept of catchpoints, which is a
5300 generalization of the old catch command. On HP-UX, it is now possible
5301 to catch exec, fork, and vfork, as well as library loading.
5303 This means that the existing catch command has changed; its first
5304 argument now specifies the type of catch to be set up. See the
5305 output of "help catch" for a list of catchpoint types.
5307 * Debugging across forks
5309 On HP-UX, you can choose which process to debug when a fork() happens
5314 HP has donated a curses-based terminal user interface (TUI). To get
5315 it, build with --enable-tui. Although this can be enabled for any
5316 configuration, at present it only works for native HP debugging.
5318 * GDB remote protocol additions
5320 A new protocol packet 'X' that writes binary data is now available.
5321 Default behavior is to try 'X', then drop back to 'M' if the stub
5322 fails to respond. The settable variable `remotebinarydownload'
5323 allows explicit control over the use of 'X'.
5325 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5326 full 64-bit address. The command
5328 set remoteaddresssize 32
5330 can be used to revert to the old behaviour. For existing remote stubs
5331 the change should not be noticed, as the additional address information
5334 In order to assist in debugging stubs, you may use the maintenance
5335 command `packet' to send any text string to the stub. For instance,
5337 maint packet heythere
5339 sends the packet "$heythere#<checksum>". Note that it is very easy to
5340 disrupt a debugging session by sending the wrong packet at the wrong
5343 The compare-sections command allows you to compare section data on the
5344 target to what is in the executable file without uploading or
5345 downloading, by comparing CRC checksums.
5347 * Tracing can collect general expressions
5349 You may now collect general expressions at tracepoints. This requires
5350 further additions to the target-side stub; see tracepoint.c and
5351 doc/agentexpr.texi for further details.
5353 * mask-address variable for Mips
5355 For Mips targets, you may control the zeroing of the upper 32 bits of
5356 a 64-bit address by entering `set mask-address on'. This is mainly
5357 of interest to users of embedded R4xxx and R5xxx processors.
5359 * Higher serial baud rates
5361 GDB's serial code now allows you to specify baud rates 57600, 115200,
5362 230400, and 460800 baud. (Note that your host system may not be able
5363 to achieve all of these rates.)
5367 The i960 configuration now includes an initial implementation of a
5368 builtin simulator, contributed by Jim Wilson.
5371 *** Changes in GDB-4.17:
5373 * New native configurations
5375 Alpha GNU/Linux alpha*-*-linux*
5376 Unixware 2.x i[3456]86-unixware2*
5377 Irix 6.x mips*-sgi-irix6*
5378 PowerPC GNU/Linux powerpc-*-linux*
5379 PowerPC Solaris powerpcle-*-solaris*
5380 Sparc GNU/Linux sparc-*-linux*
5381 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5385 Argonaut Risc Chip (ARC) arc-*-*
5386 Hitachi H8/300S h8300*-*-*
5387 Matsushita MN10200 w/simulator mn10200-*-*
5388 Matsushita MN10300 w/simulator mn10300-*-*
5389 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5390 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5391 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5392 Mitsubishi D10V w/simulator d10v-*-*
5393 Mitsubishi M32R/D w/simulator m32r-*-elf*
5394 Tsqware Sparclet sparclet-*-*
5395 NEC V850 w/simulator v850-*-*
5397 * New debugging protocols
5399 ARM with RDI protocol arm*-*-*
5400 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5401 DDB and LSI variants of PMON protocol mips*-*-*
5402 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5403 PowerPC with SDS protocol powerpc{,le}-*-eabi
5404 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5408 All configurations can now understand and use the DWARF 2 debugging
5409 format. The choice is automatic, if the symbol file contains DWARF 2
5414 GDB now includes basic Java language support. This support is
5415 only useful with Java compilers that produce native machine code.
5417 * solib-absolute-prefix and solib-search-path
5419 For SunOS and SVR4 shared libraries, you may now set the prefix for
5420 loading absolute shared library symbol files, and the search path for
5421 locating non-absolute shared library symbol files.
5423 * Live range splitting
5425 GDB can now effectively debug code for which GCC has performed live
5426 range splitting as part of its optimization. See gdb/doc/LRS for
5427 more details on the expected format of the stabs information.
5431 GDB's support for the GNU Hurd, including thread debugging, has been
5432 updated to work with current versions of the Hurd.
5436 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5437 instruction set. ARM GDB automatically detects when Thumb
5438 instructions are in use, and adjusts disassembly and backtracing
5443 GDB's MIPS target configurations now handle the MIP16 16-bit
5448 GDB now includes support for overlays; if an executable has been
5449 linked such that multiple sections are based at the same address, GDB
5450 will decide which section to use for symbolic info. You can choose to
5451 control the decision manually, using overlay commands, or implement
5452 additional target-side support and use "overlay load-target" to bring
5453 in the overlay mapping. Do "help overlay" for more detail.
5457 The command "info symbol <address>" displays information about
5458 the symbol at the specified address.
5462 The standard remote protocol now includes an extension that allows
5463 asynchronous collection and display of trace data. This requires
5464 extensive support in the target-side debugging stub. Tracing mode
5465 includes a new interaction mode in GDB and new commands: see the
5466 file tracepoint.c for more details.
5470 Configurations for embedded MIPS now include a simulator contributed
5471 by Cygnus Solutions. The simulator supports the instruction sets
5472 of most MIPS variants.
5476 Sparc configurations may now include the ERC32 simulator contributed
5477 by the European Space Agency. The simulator is not built into
5478 Sparc targets by default; configure with --enable-sim to include it.
5482 For target configurations that may include multiple variants of a
5483 basic architecture (such as MIPS and SH), you may now set the
5484 architecture explicitly. "set arch" sets, "info arch" lists
5485 the possible architectures.
5487 *** Changes in GDB-4.16:
5489 * New native configurations
5491 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5492 M68K NetBSD m68k-*-netbsd*
5493 PowerPC AIX 4.x powerpc-*-aix*
5494 PowerPC MacOS powerpc-*-macos*
5495 PowerPC Windows NT powerpcle-*-cygwin32
5496 RS/6000 AIX 4.x rs6000-*-aix4*
5500 ARM with RDP protocol arm-*-*
5501 I960 with MON960 i960-*-coff
5502 MIPS VxWorks mips*-*-vxworks*
5503 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5504 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5506 Matra Sparclet sparclet-*-*
5510 The powerpc-eabi configuration now includes the PSIM simulator,
5511 contributed by Andrew Cagney, with assistance from Mike Meissner.
5512 PSIM is a very elaborate model of the PowerPC, including not only
5513 basic instruction set execution, but also details of execution unit
5514 performance and I/O hardware. See sim/ppc/README for more details.
5518 GDB now works with Solaris 2.5.
5520 * Windows 95/NT native
5522 GDB will now work as a native debugger on Windows 95 and Windows NT.
5523 To build it from source, you must use the "gnu-win32" environment,
5524 which uses a DLL to emulate enough of Unix to run the GNU tools.
5525 Further information, binaries, and sources are available at
5526 ftp.cygnus.com, under pub/gnu-win32.
5528 * dont-repeat command
5530 If a user-defined command includes the command `dont-repeat', then the
5531 command will not be repeated if the user just types return. This is
5532 useful if the command is time-consuming to run, so that accidental
5533 extra keystrokes don't run the same command many times.
5535 * Send break instead of ^C
5537 The standard remote protocol now includes an option to send a break
5538 rather than a ^C to the target in order to interrupt it. By default,
5539 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5541 * Remote protocol timeout
5543 The standard remote protocol includes a new variable `remotetimeout'
5544 that allows you to set the number of seconds before GDB gives up trying
5545 to read from the target. The default value is 2.
5547 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5549 By default GDB will automatically keep track of objects as they are
5550 loaded and unloaded by the dynamic linker. By using the command `set
5551 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5552 when shared library events occur, thus allowing you to set breakpoints
5553 in shared libraries which are explicitly loaded by the inferior.
5555 Note this feature does not work on hpux8. On hpux9 you must link
5556 /usr/lib/end.o into your program. This feature should work
5557 automatically on hpux10.
5559 * Irix 5.x hardware watchpoint support
5561 Irix 5 configurations now support the use of hardware watchpoints.
5563 * Mips protocol "SYN garbage limit"
5565 When debugging a Mips target using the `target mips' protocol, you
5566 may set the number of characters that GDB will ignore by setting
5567 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5568 every character. The default value is 1050.
5570 * Recording and replaying remote debug sessions
5572 If you set `remotelogfile' to the name of a file, gdb will write to it
5573 a recording of a remote debug session. This recording may then be
5574 replayed back to gdb using "gdbreplay". See gdbserver/README for
5575 details. This is useful when you have a problem with GDB while doing
5576 remote debugging; you can make a recording of the session and send it
5577 to someone else, who can then recreate the problem.
5579 * Speedups for remote debugging
5581 GDB includes speedups for downloading and stepping MIPS systems using
5582 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5583 and more efficient S-record downloading.
5585 * Memory use reductions and statistics collection
5587 GDB now uses less memory and reports statistics about memory usage.
5588 Try the `maint print statistics' command, for example.
5590 *** Changes in GDB-4.15:
5592 * Psymtabs for XCOFF
5594 The symbol reader for AIX GDB now uses partial symbol tables. This
5595 can greatly improve startup time, especially for large executables.
5597 * Remote targets use caching
5599 Remote targets now use a data cache to speed up communication with the
5600 remote side. The data cache could lead to incorrect results because
5601 it doesn't know about volatile variables, thus making it impossible to
5602 debug targets which use memory mapped I/O devices. `set remotecache
5603 off' turns the the data cache off.
5605 * Remote targets may have threads
5607 The standard remote protocol now includes support for multiple threads
5608 in the target system, using new protocol commands 'H' and 'T'. See
5609 gdb/remote.c for details.
5613 If GDB is configured with `--enable-netrom', then it will include
5614 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5615 acts as though it is a bank of ROM on the target board, but you can
5616 write into it over the network. GDB's support consists only of
5617 support for fast loading into the emulated ROM; to debug, you must use
5618 another protocol, such as standard remote protocol. The usual
5619 sequence is something like
5621 target nrom <netrom-hostname>
5623 target remote <netrom-hostname>:1235
5627 GDB now includes support for the Apple Macintosh, as a host only. It
5628 may be run as either an MPW tool or as a standalone application, and
5629 it can debug through the serial port. All the usual GDB commands are
5630 available, but to the target command, you must supply "serial" as the
5631 device type instead of "/dev/ttyXX". See mpw-README in the main
5632 directory for more information on how to build. The MPW configuration
5633 scripts */mpw-config.in support only a few targets, and only the
5634 mips-idt-ecoff target has been tested.
5638 GDB configuration now uses autoconf. This is not user-visible,
5639 but does simplify configuration and building.
5643 GDB now supports hpux10.
5645 *** Changes in GDB-4.14:
5647 * New native configurations
5649 x86 FreeBSD i[345]86-*-freebsd
5650 x86 NetBSD i[345]86-*-netbsd
5651 NS32k NetBSD ns32k-*-netbsd
5652 Sparc NetBSD sparc-*-netbsd
5656 A29K VxWorks a29k-*-vxworks
5657 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5658 CPU32 EST-300 emulator m68*-*-est*
5659 PowerPC ELF powerpc-*-elf
5662 * Alpha OSF/1 support for procfs
5664 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5665 possible to attach to running processes. As the mounting of the /proc
5666 filesystem is optional on the Alpha, GDB automatically determines
5667 the availability of /proc during startup. This can lead to problems
5668 if /proc is unmounted after GDB has been started.
5670 * Arguments to user-defined commands
5672 User commands may accept up to 10 arguments separated by whitespace.
5673 Arguments are accessed within the user command via $arg0..$arg9. A
5676 print $arg0 + $arg1 + $arg2
5678 To execute the command use:
5681 Defines the command "adder" which prints the sum of its three arguments.
5682 Note the arguments are text substitutions, so they may reference variables,
5683 use complex expressions, or even perform inferior function calls.
5685 * New `if' and `while' commands
5687 This makes it possible to write more sophisticated user-defined
5688 commands. Both commands take a single argument, which is the
5689 expression to evaluate, and must be followed by the commands to
5690 execute, one per line, if the expression is nonzero, the list being
5691 terminated by the word `end'. The `if' command list may include an
5692 `else' word, which causes the following commands to be executed only
5693 if the expression is zero.
5695 * Fortran source language mode
5697 GDB now includes partial support for Fortran 77. It will recognize
5698 Fortran programs and can evaluate a subset of Fortran expressions, but
5699 variables and functions may not be handled correctly. GDB will work
5700 with G77, but does not yet know much about symbols emitted by other
5703 * Better HPUX support
5705 Most debugging facilities now work on dynamic executables for HPPAs
5706 running hpux9 or later. You can attach to running dynamically linked
5707 processes, but by default the dynamic libraries will be read-only, so
5708 for instance you won't be able to put breakpoints in them. To change
5709 that behavior do the following before running the program:
5715 This will cause the libraries to be mapped private and read-write.
5716 To revert to the normal behavior, do this:
5722 You cannot set breakpoints or examine data in the library until after
5723 the library is loaded if the function/data symbols do not have
5726 GDB can now also read debug symbols produced by the HP C compiler on
5727 HPPAs (sorry, no C++, Fortran or 68k support).
5729 * Target byte order now dynamically selectable
5731 You can choose which byte order to use with a target system, via the
5732 commands "set endian big" and "set endian little", and you can see the
5733 current setting by using "show endian". You can also give the command
5734 "set endian auto", in which case GDB will use the byte order
5735 associated with the executable. Currently, only embedded MIPS
5736 configurations support dynamic selection of target byte order.
5738 * New DOS host serial code
5740 This version uses DPMI interrupts to handle buffered I/O, so you
5741 no longer need to run asynctsr when debugging boards connected to
5744 *** Changes in GDB-4.13:
5746 * New "complete" command
5748 This lists all the possible completions for the rest of the line, if it
5749 were to be given as a command itself. This is intended for use by emacs.
5751 * Trailing space optional in prompt
5753 "set prompt" no longer adds a space for you after the prompt you set. This
5754 allows you to set a prompt which ends in a space or one that does not.
5756 * Breakpoint hit counts
5758 "info break" now displays a count of the number of times the breakpoint
5759 has been hit. This is especially useful in conjunction with "ignore"; you
5760 can ignore a large number of breakpoint hits, look at the breakpoint info
5761 to see how many times the breakpoint was hit, then run again, ignoring one
5762 less than that number, and this will get you quickly to the last hit of
5765 * Ability to stop printing at NULL character
5767 "set print null-stop" will cause GDB to stop printing the characters of
5768 an array when the first NULL is encountered. This is useful when large
5769 arrays actually contain only short strings.
5771 * Shared library breakpoints
5773 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5774 breakpoints in shared libraries before the executable is run.
5776 * Hardware watchpoints
5778 There is a new hardware breakpoint for the watch command for sparclite
5779 targets. See gdb/sparclite/hw_breakpoint.note.
5781 Hardware watchpoints are also now supported under GNU/Linux.
5785 Annotations have been added. These are for use with graphical interfaces,
5786 and are still experimental. Currently only gdba.el uses these.
5788 * Improved Irix 5 support
5790 GDB now works properly with Irix 5.2.
5792 * Improved HPPA support
5794 GDB now works properly with the latest GCC and GAS.
5796 * New native configurations
5798 Sequent PTX4 i[34]86-sequent-ptx4
5799 HPPA running OSF/1 hppa*-*-osf*
5800 Atari TT running SVR4 m68*-*-sysv4*
5801 RS/6000 LynxOS rs6000-*-lynxos*
5805 OS/9000 i[34]86-*-os9k
5806 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5809 * Hitachi SH7000 and E7000-PC ICE support
5811 There is now support for communicating with the Hitachi E7000-PC ICE.
5812 This is available automatically when GDB is configured for the SH.
5816 As usual, a variety of small fixes and improvements, both generic
5817 and configuration-specific. See the ChangeLog for more detail.
5819 *** Changes in GDB-4.12:
5821 * Irix 5 is now supported
5825 GDB-4.12 on the HPPA has a number of changes which make it unable
5826 to debug the output from the currently released versions of GCC and
5827 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5828 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5829 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5832 *** Changes in GDB-4.11:
5834 * User visible changes:
5838 The "set remotedebug" option is now consistent between the mips remote
5839 target, remote targets using the gdb-specific protocol, UDI (AMD's
5840 debug protocol for the 29k) and the 88k bug monitor. It is now an
5841 integer specifying a debug level (normally 0 or 1, but 2 means more
5842 debugging info for the mips target).
5844 * DEC Alpha native support
5846 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5847 debug info, but GDB works fairly well with the DEC compiler and should
5848 work with a future GCC release. See the README file for a few
5849 Alpha-specific notes.
5851 * Preliminary thread implementation
5853 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5855 * LynxOS native and target support for 386
5857 This release has been hosted on LynxOS 2.2, and also can be configured
5858 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5861 * Improvements in C++ mangling/demangling.
5863 This release has much better g++ debugging, specifically in name
5864 mangling/demangling, virtual function calls, print virtual table,
5865 call methods, ...etc.
5867 *** Changes in GDB-4.10:
5869 * User visible changes:
5871 Remote debugging using the GDB-specific (`target remote') protocol now
5872 supports the `load' command. This is only useful if you have some
5873 other way of getting the stub to the target system, and you can put it
5874 somewhere in memory where it won't get clobbered by the download.
5876 Filename completion now works.
5878 When run under emacs mode, the "info line" command now causes the
5879 arrow to point to the line specified. Also, "info line" prints
5880 addresses in symbolic form (as well as hex).
5882 All vxworks based targets now support a user settable option, called
5883 vxworks-timeout. This option represents the number of seconds gdb
5884 should wait for responses to rpc's. You might want to use this if
5885 your vxworks target is, perhaps, a slow software simulator or happens
5886 to be on the far side of a thin network line.
5890 This release contains support for using a DEC alpha as a GDB host for
5891 cross debugging. Native alpha debugging is not supported yet.
5894 *** Changes in GDB-4.9:
5898 This is the first GDB release which is accompanied by a matching testsuite.
5899 The testsuite requires installation of dejagnu, which should be available
5900 via ftp from most sites that carry GNU software.
5904 'Cfront' style demangling has had its name changed to 'ARM' style, to
5905 emphasize that it was written from the specifications in the C++ Annotated
5906 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5907 disclaimers, it still generated too much confusion with users attempting to
5908 use gdb with AT&T cfront.
5912 GDB now uses a standard remote interface to a simulator library.
5913 So far, the library contains simulators for the Zilog Z8001/2, the
5914 Hitachi H8/300, H8/500 and Super-H.
5916 * New targets supported
5918 H8/300 simulator h8300-hitachi-hms or h8300hms
5919 H8/500 simulator h8500-hitachi-hms or h8500hms
5920 SH simulator sh-hitachi-hms or sh
5921 Z8000 simulator z8k-zilog-none or z8ksim
5922 IDT MIPS board over serial line mips-idt-ecoff
5924 Cross-debugging to GO32 targets is supported. It requires a custom
5925 version of the i386-stub.c module which is integrated with the
5926 GO32 memory extender.
5928 * New remote protocols
5930 MIPS remote debugging protocol.
5932 * New source languages supported
5934 This version includes preliminary support for Chill, a Pascal like language
5935 used by telecommunications companies. Chill support is also being integrated
5936 into the GNU compiler, but we don't know when it will be publically available.
5939 *** Changes in GDB-4.8:
5941 * HP Precision Architecture supported
5943 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5944 version of this support was available as a set of patches from the
5945 University of Utah. GDB does not support debugging of programs
5946 compiled with the HP compiler, because HP will not document their file
5947 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5948 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5950 Many problems in the preliminary version have been fixed.
5952 * Faster and better demangling
5954 We have improved template demangling and fixed numerous bugs in the GNU style
5955 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5956 character types (wchar_t) are now supported. Demangling of each symbol is now
5957 only done once, and is cached when the symbol table for a file is read in.
5958 This results in a small increase in memory usage for C programs, a moderate
5959 increase in memory usage for C++ programs, and a fantastic speedup in
5962 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5963 from the specifications in the Annotated Reference Manual, which AT&T's
5964 compiler does not actually implement.
5966 * G++ multiple inheritance compiler problem
5968 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5969 inheritance lattices was reworked to properly discover ambiguities. We
5970 recently found an example which causes this new algorithm to fail in a
5971 very subtle way, producing bad debug information for those classes.
5972 The file 'gcc.patch' (in this directory) can be applied to gcc to
5973 circumvent the problem. A future GCC release will contain a complete
5976 The previous G++ debug info problem (mentioned below for the gdb-4.7
5977 release) is fixed in gcc version 2.3.2.
5979 * Improved configure script
5981 The `configure' script will now attempt to guess your system type if
5982 you don't supply a host system type. The old scheme of supplying a
5983 host system triplet is preferable over using this. All the magic is
5984 done in the new `config.guess' script. Examine it for details.
5986 We have also brought our configure script much more in line with the FSF's
5987 version. It now supports the --with-xxx options. In particular,
5988 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5989 The resulting GDB will not be able to read arbitrary object file formats --
5990 only the format ``expected'' to be used on the configured target system.
5991 We hope to make this the default in a future release.
5993 * Documentation improvements
5995 There's new internal documentation on how to modify GDB, and how to
5996 produce clean changes to the code. We implore people to read it
5997 before submitting changes.
5999 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6000 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6001 `info' files are also provided. To build `info' files from scratch,
6002 you will need the latest `makeinfo' release, which will be available in
6003 a future texinfo-X.Y release.
6005 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6006 We're not sure exactly which versions have this problem, but it has
6007 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6008 or better. If that isn't possible, there is a patch in
6009 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6010 around this problem.
6014 GDB now supports array constants that can be used in expressions typed in by
6015 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6016 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6019 The new directory `gdb/sparclite' contains a program that demonstrates
6020 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6022 * New native hosts supported
6024 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6025 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6027 * New targets supported
6029 AMD 29k family via UDI a29k-amd-udi or udi29k
6031 * New file formats supported
6033 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6034 HPUX core files, and SCO 3.2v2 core files.
6038 Attaching to processes now works again; thanks for the many bug reports.
6040 We have also stomped on a bunch of core dumps caused by
6041 printf_filtered("%s") problems.
6043 We eliminated a copyright problem on the rpc and ptrace header files
6044 for VxWorks, which was discovered at the last minute during the 4.7
6045 release. You should now be able to build a VxWorks GDB.
6047 You can now interrupt gdb while an attached process is running. This
6048 will cause the attached process to stop, and give control back to GDB.
6050 We fixed problems caused by using too many file descriptors
6051 for reading symbols from object files and libraries. This was
6052 especially a problem for programs that used many (~100) shared
6055 The `step' command now only enters a subroutine if there is line number
6056 information for the subroutine. Otherwise it acts like the `next'
6057 command. Previously, `step' would enter subroutines if there was
6058 any debugging information about the routine. This avoids problems
6059 when using `cc -g1' on MIPS machines.
6061 * Internal improvements
6063 GDB's internal interfaces have been improved to make it easier to support
6064 debugging of multiple languages in the future.
6066 GDB now uses a common structure for symbol information internally.
6067 Minimal symbols (derived from linkage symbols in object files), partial
6068 symbols (from a quick scan of debug information), and full symbols
6069 contain a common subset of information, making it easier to write
6070 shared code that handles any of them.
6072 * New command line options
6074 We now accept --silent as an alias for --quiet.
6078 The memory-mapped-malloc library is now licensed under the GNU Library
6079 General Public License.
6081 *** Changes in GDB-4.7:
6083 * Host/native/target split
6085 GDB has had some major internal surgery to untangle the support for
6086 hosts and remote targets. Now, when you configure GDB for a remote
6087 target, it will no longer load in all of the support for debugging
6088 local programs on the host. When fully completed and tested, this will
6089 ensure that arbitrary host/target combinations are possible.
6091 The primary conceptual shift is to separate the non-portable code in
6092 GDB into three categories. Host specific code is required any time GDB
6093 is compiled on that host, regardless of the target. Target specific
6094 code relates to the peculiarities of the target, but can be compiled on
6095 any host. Native specific code is everything else: it can only be
6096 built when the host and target are the same system. Child process
6097 handling and core file support are two common `native' examples.
6099 GDB's use of /proc for controlling Unix child processes is now cleaner.
6100 It has been split out into a single module under the `target_ops' vector,
6101 plus two native-dependent functions for each system that uses /proc.
6103 * New hosts supported
6105 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6106 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6107 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6109 * New targets supported
6111 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6112 68030 and CPU32 m68030-*-*, m68332-*-*
6114 * New native hosts supported
6116 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6117 (386bsd is not well tested yet)
6118 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6120 * New file formats supported
6122 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6123 supports reading of `a.out.adobe' object files, which are an a.out
6124 format extended with minimal information about multiple sections.
6128 `show copying' is the same as the old `info copying'.
6129 `show warranty' is the same as `info warrantee'.
6130 These were renamed for consistency. The old commands continue to work.
6132 `info handle' is a new alias for `info signals'.
6134 You can now define pre-command hooks, which attach arbitrary command
6135 scripts to any command. The commands in the hook will be executed
6136 prior to the user's command. You can also create a hook which will be
6137 executed whenever the program stops. See gdb.texinfo.
6141 We now deal with Cfront style name mangling, and can even extract type
6142 info from mangled symbols. GDB can automatically figure out which
6143 symbol mangling style your C++ compiler uses.
6145 Calling of methods and virtual functions has been improved as well.
6149 The crash that occured when debugging Sun Ansi-C compiled binaries is
6150 fixed. This was due to mishandling of the extra N_SO stabs output
6153 We also finally got Ultrix 4.2 running in house, and fixed core file
6154 support, with help from a dozen people on the net.
6156 John M. Farrell discovered that the reason that single-stepping was so
6157 slow on all of the Mips based platforms (primarily SGI and DEC) was
6158 that we were trying to demangle and lookup a symbol used for internal
6159 purposes on every instruction that was being stepped through. Changing
6160 the name of that symbol so that it couldn't be mistaken for a C++
6161 mangled symbol sped things up a great deal.
6163 Rich Pixley sped up symbol lookups in general by getting much smarter
6164 about when C++ symbol mangling is necessary. This should make symbol
6165 completion (TAB on the command line) much faster. It's not as fast as
6166 we'd like, but it's significantly faster than gdb-4.6.
6170 A new user controllable variable 'call_scratch_address' can
6171 specify the location of a scratch area to be used when GDB
6172 calls a function in the target. This is necessary because the
6173 usual method of putting the scratch area on the stack does not work
6174 in systems that have separate instruction and data spaces.
6176 We integrated changes to support the 29k UDI (Universal Debugger
6177 Interface), but discovered at the last minute that we didn't have all
6178 of the appropriate copyright paperwork. We are working with AMD to
6179 resolve this, and hope to have it available soon.
6183 We have sped up the remote serial line protocol, especially for targets
6184 with lots of registers. It now supports a new `expedited status' ('T')
6185 message which can be used in place of the existing 'S' status message.
6186 This allows the remote stub to send only the registers that GDB
6187 needs to make a quick decision about single-stepping or conditional
6188 breakpoints, eliminating the need to fetch the entire register set for
6189 each instruction being stepped through.
6191 The GDB remote serial protocol now implements a write-through cache for
6192 registers, only re-reading the registers if the target has run.
6194 There is also a new remote serial stub for SPARC processors. You can
6195 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6196 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6197 processor with a serial port.
6201 Configure.in files have become much easier to read and modify. A new
6202 `table driven' format makes it more obvious what configurations are
6203 supported, and what files each one uses.
6207 There is a new opcodes library which will eventually contain all of the
6208 disassembly routines and opcode tables. At present, it only contains
6209 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6210 disassembler (binutils/objdump) to share these routines.
6212 The libiberty library is now copylefted under the GNU Library General
6213 Public License. This allows more liberal use, and was done so libg++
6214 can use it. This makes no difference to GDB, since the Library License
6215 grants all the rights from the General Public License.
6219 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6220 reference to the stabs symbol info used by the debugger. It is (as far
6221 as we know) the only published document on this fascinating topic. We
6222 encourage you to read it, compare it to the stabs information on your
6223 system, and send improvements on the document in general (to
6224 bug-gdb@prep.ai.mit.edu).
6226 And, of course, many bugs have been fixed.
6229 *** Changes in GDB-4.6:
6231 * Better support for C++ function names
6233 GDB now accepts as input the "demangled form" of C++ overloaded function
6234 names and member function names, and can do command completion on such names
6235 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6236 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6237 Make use of command completion, it is your friend.
6239 GDB also now accepts a variety of C++ mangled symbol formats. They are
6240 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6241 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6242 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6243 for the list of formats.
6245 * G++ symbol mangling problem
6247 Recent versions of gcc have a bug in how they emit debugging information for
6248 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6249 directory) can be applied to gcc to fix the problem. Alternatively, if you
6250 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6251 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6252 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6255 * New 'maintenance' command
6257 All of the commands related to hacking GDB internals have been moved out of
6258 the main command set, and now live behind the 'maintenance' command. This
6259 can also be abbreviated as 'mt'. The following changes were made:
6261 dump-me -> maintenance dump-me
6262 info all-breakpoints -> maintenance info breakpoints
6263 printmsyms -> maintenance print msyms
6264 printobjfiles -> maintenance print objfiles
6265 printpsyms -> maintenance print psymbols
6266 printsyms -> maintenance print symbols
6268 The following commands are new:
6270 maintenance demangle Call internal GDB demangler routine to
6271 demangle a C++ link name and prints the result.
6272 maintenance print type Print a type chain for a given symbol
6274 * Change to .gdbinit file processing
6276 We now read the $HOME/.gdbinit file before processing the argv arguments
6277 (e.g. reading symbol files or core files). This allows global parameters to
6278 be set, which will apply during the symbol reading. The ./.gdbinit is still
6279 read after argv processing.
6281 * New hosts supported
6283 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6285 GNU/Linux support i386-unknown-linux or linux
6287 We are also including code to support the HP/PA running BSD and HPUX. This
6288 is almost guaranteed not to work, as we didn't have time to test or build it
6289 for this release. We are including it so that the more adventurous (or
6290 masochistic) of you can play with it. We also had major problems with the
6291 fact that the compiler that we got from HP doesn't support the -g option.
6294 * New targets supported
6296 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6298 * More smarts about finding #include files
6300 GDB now remembers the compilation directory for all include files, and for
6301 all files from which C is generated (like yacc and lex sources). This
6302 greatly improves GDB's ability to find yacc/lex sources, and include files,
6303 especially if you are debugging your program from a directory different from
6304 the one that contains your sources.
6306 We also fixed a bug which caused difficulty with listing and setting
6307 breakpoints in include files which contain C code. (In the past, you had to
6308 try twice in order to list an include file that you hadn't looked at before.)
6310 * Interesting infernals change
6312 GDB now deals with arbitrary numbers of sections, where the symbols for each
6313 section must be relocated relative to that section's landing place in the
6314 target's address space. This work was needed to support ELF with embedded
6315 stabs used by Solaris-2.0.
6317 * Bug fixes (of course!)
6319 There have been loads of fixes for the following things:
6320 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6321 i960, stabs, DOS(GO32), procfs, etc...
6323 See the ChangeLog for details.
6325 *** Changes in GDB-4.5:
6327 * New machines supported (host and target)
6329 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6331 SGI Irix-4.x mips-sgi-irix4 or iris4
6333 * New malloc package
6335 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6336 Mmalloc is capable of handling mutiple heaps of memory. It is also
6337 capable of saving a heap to a file, and then mapping it back in later.
6338 This can be used to greatly speedup the startup of GDB by using a
6339 pre-parsed symbol table which lives in a mmalloc managed heap. For
6340 more details, please read mmalloc/mmalloc.texi.
6344 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6345 'help info proc' for details.
6347 * MIPS ecoff symbol table format
6349 The code that reads MIPS symbol table format is now supported on all hosts.
6350 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6353 * File name changes for MS-DOS
6355 Many files in the config directories have been renamed to make it easier to
6356 support GDB on MS-DOSe systems (which have very restrictive file name
6357 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6358 environment) is close to working but has some remaining problems. Note
6359 that debugging of DOS programs is not supported, due to limitations
6360 in the ``operating system'', but it can be used to host cross-debugging.
6362 * Cross byte order fixes
6364 Many fixes have been made to support cross debugging of Sparc and MIPS
6365 targets from hosts whose byte order differs.
6367 * New -mapped and -readnow options
6369 If memory-mapped files are available on your system through the 'mmap'
6370 system call, you can use the -mapped option on the `file' or
6371 `symbol-file' commands to cause GDB to write the symbols from your
6372 program into a reusable file. If the program you are debugging is
6373 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6374 Future GDB debugging sessions will notice the presence of this file,
6375 and will quickly map in symbol information from it, rather than reading
6376 the symbol table from the executable program. Using the '-mapped'
6377 option in a GDB `file' or `symbol-file' command has the same effect as
6378 starting GDB with the '-mapped' command-line option.
6380 You can cause GDB to read the entire symbol table immediately by using
6381 the '-readnow' option with any of the commands that load symbol table
6382 information (or on the GDB command line). This makes the command
6383 slower, but makes future operations faster.
6385 The -mapped and -readnow options are typically combined in order to
6386 build a `fred.syms' file that contains complete symbol information.
6387 A simple GDB invocation to do nothing but build a `.syms' file for future
6390 gdb -batch -nx -mapped -readnow programname
6392 The `.syms' file is specific to the host machine on which GDB is run.
6393 It holds an exact image of GDB's internal symbol table. It cannot be
6394 shared across multiple host platforms.
6396 * longjmp() handling
6398 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6399 siglongjmp() without losing control. This feature has not yet been ported to
6400 all systems. It currently works on many 386 platforms, all MIPS-based
6401 platforms (SGI, DECstation, etc), and Sun3/4.
6405 Preliminary work has been put in to support the new Solaris OS from Sun. At
6406 this time, it can control and debug processes, but it is not capable of
6411 As always, many many bug fixes. The major areas were with g++, and mipsread.
6412 People using the MIPS-based platforms should experience fewer mysterious
6413 crashes and trashed symbol tables.
6415 *** Changes in GDB-4.4:
6417 * New machines supported (host and target)
6419 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6421 BSD Reno on Vax vax-dec-bsd
6422 Ultrix on Vax vax-dec-ultrix
6424 * New machines supported (target)
6426 AMD 29000 embedded, using EBMON a29k-none-none
6430 GDB continues to improve its handling of C++. `References' work better.
6431 The demangler has also been improved, and now deals with symbols mangled as
6432 per the Annotated C++ Reference Guide.
6434 GDB also now handles `stabs' symbol information embedded in MIPS
6435 `ecoff' symbol tables. Since the ecoff format was not easily
6436 extensible to handle new languages such as C++, this appeared to be a
6437 good way to put C++ debugging info into MIPS binaries. This option
6438 will be supported in the GNU C compiler, version 2, when it is
6441 * New features for SVR4
6443 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6444 shared libraries. Debugging dynamically linked programs should present
6445 only minor differences from debugging statically linked programs.
6447 The `info proc' command will print out information about any process
6448 on an SVR4 system (including the one you are debugging). At the moment,
6449 it prints the address mappings of the process.
6451 If you bring up GDB on another SVR4 system, please send mail to
6452 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6454 * Better dynamic linking support in SunOS
6456 Reading symbols from shared libraries which contain debugging symbols
6457 now works properly. However, there remain issues such as automatic
6458 skipping of `transfer vector' code during function calls, which
6459 make it harder to debug code in a shared library, than to debug the
6460 same code linked statically.
6464 GDB is now using the latest `getopt' routines from the FSF. This
6465 version accepts the -- prefix for options with long names. GDB will
6466 continue to accept the old forms (-option and +option) as well.
6467 Various single letter abbreviations for options have been explicity
6468 added to the option table so that they won't get overshadowed in the
6469 future by other options that begin with the same letter.
6473 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6474 Many assorted bugs have been handled. Many more remain to be handled.
6475 See the various ChangeLog files (primarily in gdb and bfd) for details.
6478 *** Changes in GDB-4.3:
6480 * New machines supported (host and target)
6482 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6483 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6484 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6486 * Almost SCO Unix support
6488 We had hoped to support:
6489 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6490 (except for core file support), but we discovered very late in the release
6491 that it has problems with process groups that render gdb unusable. Sorry
6492 about that. I encourage people to fix it and post the fixes.
6494 * Preliminary ELF and DWARF support
6496 GDB can read ELF object files on System V Release 4, and can handle
6497 debugging records for C, in DWARF format, in ELF files. This support
6498 is preliminary. If you bring up GDB on another SVR4 system, please
6499 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6504 GDB now uses the latest `readline' library. One user-visible change
6505 is that two tabs will list possible command completions, which previously
6506 required typing M-? (meta-question mark, or ESC ?).
6510 The `stepi' bug that many of you noticed has been squashed.
6511 Many bugs in C++ have been handled. Many more remain to be handled.
6512 See the various ChangeLog files (primarily in gdb and bfd) for details.
6514 * State of the MIPS world (in case you wondered):
6516 GDB can understand the symbol tables emitted by the compilers
6517 supplied by most vendors of MIPS-based machines, including DEC. These
6518 symbol tables are in a format that essentially nobody else uses.
6520 Some versions of gcc come with an assembler post-processor called
6521 mips-tfile. This program is required if you want to do source-level
6522 debugging of gcc-compiled programs. I believe FSF does not ship
6523 mips-tfile with gcc version 1, but it will eventually come with gcc
6526 Debugging of g++ output remains a problem. g++ version 1.xx does not
6527 really support it at all. (If you're lucky, you should be able to get
6528 line numbers and stack traces to work, but no parameters or local
6529 variables.) With some work it should be possible to improve the
6532 When gcc version 2 is released, you will have somewhat better luck.
6533 However, even then you will get confusing results for inheritance and
6536 We will eventually provide full debugging of g++ output on
6537 DECstations. This will probably involve some kind of stabs-in-ecoff
6538 encapulation, but the details have not been worked out yet.
6541 *** Changes in GDB-4.2:
6543 * Improved configuration
6545 Only one copy of `configure' exists now, and it is not self-modifying.
6546 Porting BFD is simpler.
6550 The `step' and `next' commands now only stop at the first instruction
6551 of a source line. This prevents the multiple stops that used to occur
6552 in switch statements, for-loops, etc. `Step' continues to stop if a
6553 function that has debugging information is called within the line.
6557 Lots of small bugs fixed. More remain.
6559 * New host supported (not target)
6561 Intel 386 PC clone running Mach i386-none-mach
6564 *** Changes in GDB-4.1:
6566 * Multiple source language support
6568 GDB now has internal scaffolding to handle several source languages.
6569 It determines the type of each source file from its filename extension,
6570 and will switch expression parsing and number formatting to match the
6571 language of the function in the currently selected stack frame.
6572 You can also specifically set the language to be used, with
6573 `set language c' or `set language modula-2'.
6577 GDB now has preliminary support for the GNU Modula-2 compiler,
6578 currently under development at the State University of New York at
6579 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6580 continue through the fall of 1991 and into 1992.
6582 Other Modula-2 compilers are currently not supported, and attempting to
6583 debug programs compiled with them will likely result in an error as the
6584 symbol table is read. Feel free to work on it, though!
6586 There are hooks in GDB for strict type checking and range checking,
6587 in the `Modula-2 philosophy', but they do not currently work.
6591 GDB can now write to executable and core files (e.g. patch
6592 a variable's value). You must turn this switch on, specify
6593 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6594 by assigning a new value to a variable. Modifications take
6597 * Automatic SunOS shared library reading
6599 When you run your program, GDB automatically determines where its
6600 shared libraries (if any) have been loaded, and reads their symbols.
6601 The `share' command is no longer needed. This also works when
6602 examining core files.
6606 You can specify the number of lines that the `list' command shows.
6609 * New machines supported (host and target)
6611 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6612 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6613 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6615 * New hosts supported (not targets)
6617 IBM RT/PC: romp-ibm-aix or rtpc
6619 * New targets supported (not hosts)
6621 AMD 29000 embedded with COFF a29k-none-coff
6622 AMD 29000 embedded with a.out a29k-none-aout
6623 Ultracomputer remote kernel debug a29k-nyu-kern
6625 * New remote interfaces
6631 *** Changes in GDB-4.0:
6635 Wide output is wrapped at good places to make the output more readable.
6637 Gdb now supports cross-debugging from a host machine of one type to a
6638 target machine of another type. Communication with the target system
6639 is over serial lines. The ``target'' command handles connecting to the
6640 remote system; the ``load'' command will download a program into the
6641 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6642 also supports debugging of realtime processes running under VxWorks,
6643 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6644 stub on the target system.
6646 New CPUs supported include the AMD 29000 and Intel 960.
6648 GDB now reads object files and symbol tables via a ``binary file''
6649 library, which allows a single copy of GDB to debug programs of multiple
6650 object file types such as a.out and coff.
6652 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6653 refcard.dvi and refcard.ps are available to format it).
6656 * Control-Variable user interface simplified
6658 All variables that control the operation of the debugger can be set
6659 by the ``set'' command, and displayed by the ``show'' command.
6661 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6662 ``Show prompt'' produces the response:
6663 Gdb's prompt is new-gdb=>.
6665 What follows are the NEW set commands. The command ``help set'' will
6666 print a complete list of old and new set commands. ``help set FOO''
6667 will give a longer description of the variable FOO. ``show'' will show
6668 all of the variable descriptions and their current settings.
6670 confirm on/off: Enables warning questions for operations that are
6671 hard to recover from, e.g. rerunning the program while
6672 it is already running. Default is ON.
6674 editing on/off: Enables EMACS style command line editing
6675 of input. Previous lines can be recalled with
6676 control-P, the current line can be edited with control-B,
6677 you can search for commands with control-R, etc.
6680 history filename NAME: NAME is where the gdb command history
6681 will be stored. The default is .gdb_history,
6682 or the value of the environment variable
6685 history size N: The size, in commands, of the command history. The
6686 default is 256, or the value of the environment variable
6689 history save on/off: If this value is set to ON, the history file will
6690 be saved after exiting gdb. If set to OFF, the
6691 file will not be saved. The default is OFF.
6693 history expansion on/off: If this value is set to ON, then csh-like
6694 history expansion will be performed on
6695 command line input. The default is OFF.
6697 radix N: Sets the default radix for input and output. It can be set
6698 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6699 in the current radix, so "set radix 10" is always a no-op.
6701 height N: This integer value is the number of lines on a page. Default
6702 is 24, the current `stty rows'' setting, or the ``li#''
6703 setting from the termcap entry matching the environment
6706 width N: This integer value is the number of characters on a line.
6707 Default is 80, the current `stty cols'' setting, or the ``co#''
6708 setting from the termcap entry matching the environment
6711 Note: ``set screensize'' is obsolete. Use ``set height'' and
6712 ``set width'' instead.
6714 print address on/off: Print memory addresses in various command displays,
6715 such as stack traces and structure values. Gdb looks
6716 more ``symbolic'' if you turn this off; it looks more
6717 ``machine level'' with it on. Default is ON.
6719 print array on/off: Prettyprint arrays. New convenient format! Default
6722 print demangle on/off: Print C++ symbols in "source" form if on,
6725 print asm-demangle on/off: Same, for assembler level printouts
6728 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6731 * Support for Epoch Environment.
6733 The epoch environment is a version of Emacs v18 with windowing. One
6734 new command, ``inspect'', is identical to ``print'', except that if you
6735 are running in the epoch environment, the value is printed in its own
6739 * Support for Shared Libraries
6741 GDB can now debug programs and core files that use SunOS shared libraries.
6742 Symbols from a shared library cannot be referenced
6743 before the shared library has been linked with the program (this
6744 happens after you type ``run'' and before the function main() is entered).
6745 At any time after this linking (including when examining core files
6746 from dynamically linked programs), gdb reads the symbols from each
6747 shared library when you type the ``sharedlibrary'' command.
6748 It can be abbreviated ``share''.
6750 sharedlibrary REGEXP: Load shared object library symbols for files
6751 matching a unix regular expression. No argument
6752 indicates to load symbols for all shared libraries.
6754 info sharedlibrary: Status of loaded shared libraries.
6759 A watchpoint stops execution of a program whenever the value of an
6760 expression changes. Checking for this slows down execution
6761 tremendously whenever you are in the scope of the expression, but is
6762 quite useful for catching tough ``bit-spreader'' or pointer misuse
6763 problems. Some machines such as the 386 have hardware for doing this
6764 more quickly, and future versions of gdb will use this hardware.
6766 watch EXP: Set a watchpoint (breakpoint) for an expression.
6768 info watchpoints: Information about your watchpoints.
6770 delete N: Deletes watchpoint number N (same as breakpoints).
6771 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6772 enable N: Re-enables watchpoint number N (same as breakpoints).
6775 * C++ multiple inheritance
6777 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6780 * C++ exception handling
6782 Gdb now supports limited C++ exception handling. Besides the existing
6783 ability to breakpoint on an exception handler, gdb can breakpoint on
6784 the raising of an exception (before the stack is peeled back to the
6787 catch FOO: If there is a FOO exception handler in the dynamic scope,
6788 set a breakpoint to catch exceptions which may be raised there.
6789 Multiple exceptions (``catch foo bar baz'') may be caught.
6791 info catch: Lists all exceptions which may be caught in the
6792 current stack frame.
6795 * Minor command changes
6797 The command ``call func (arg, arg, ...)'' now acts like the print
6798 command, except it does not print or save a value if the function's result
6799 is void. This is similar to dbx usage.
6801 The ``up'' and ``down'' commands now always print the frame they end up
6802 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6803 frames without printing.
6805 * New directory command
6807 'dir' now adds directories to the FRONT of the source search path.
6808 The path starts off empty. Source files that contain debug information
6809 about the directory in which they were compiled can be found even
6810 with an empty path; Sun CC and GCC include this information. If GDB can't
6811 find your source file in the current directory, type "dir .".
6813 * Configuring GDB for compilation
6815 For normal use, type ``./configure host''. See README or gdb.texinfo
6818 GDB now handles cross debugging. If you are remotely debugging between
6819 two different machines, type ``./configure host -target=targ''.
6820 Host is the machine where GDB will run; targ is the machine
6821 where the program that you are debugging will run.