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.
78 * The "enable", and "disable" commands now accept a range of
79 breakpoint locations, e.g. "enable 1.3-5".
84 Set and show the current working directory for the inferior.
87 Set and show compilation command used for compiling and injecting code
88 with the 'compile' commands.
90 set debug separate-debug-file
91 show debug separate-debug-file
92 Control the display of debug output about separate debug file search.
95 List the registered selftests.
98 Start the debugged program stopping at the first instruction.
100 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
103 * Safer/improved support for debugging with no debug info
105 GDB no longer assumes functions with no debug information return
108 This means that GDB now refuses to call such functions unless you
109 tell it the function's type, by either casting the call to the
110 declared return type, or by casting the function to a function
111 pointer of the right type, and calling that:
113 (gdb) p getenv ("PATH")
114 'getenv' has unknown return type; cast the call to its declared return type
115 (gdb) p (char *) getenv ("PATH")
116 $1 = 0x7fffffffe "/usr/local/bin:/"...
117 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
118 $2 = 0x7fffffffe "/usr/local/bin:/"...
120 Similarly, GDB no longer assumes that global variables with no debug
121 info have type 'int', and refuses to print the variable's value
122 unless you tell it the variable's type:
125 'var' has unknown type; cast it to its declared type
129 * New native configurations
131 FreeBSD/aarch64 aarch64*-*-freebsd*
132 FreeBSD/arm arm*-*-freebsd*
136 FreeBSD/aarch64 aarch64*-*-freebsd*
137 FreeBSD/arm arm*-*-freebsd*
139 * Removed targets and native configurations
141 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
143 *** Changes in GDB 8.0
145 * GDB now supports access to the PKU register on GNU/Linux. The register is
146 added by the Memory Protection Keys for Userspace feature which will be
147 available in future Intel CPUs.
149 * GDB now supports C++11 rvalue references.
153 ** New functions to start, stop and access a running btrace recording.
154 ** Rvalue references are now supported in gdb.Type.
156 * GDB now supports recording and replaying rdrand and rdseed Intel 64
159 * Building GDB and GDBserver now requires a C++11 compiler.
161 For example, GCC 4.8 or later.
163 It is no longer possible to build GDB or GDBserver with a C
164 compiler. The --disable-build-with-cxx configure option has been
167 * Building GDB and GDBserver now requires GNU make >= 3.81.
169 It is no longer supported to build GDB or GDBserver with another
170 implementation of the make program or an earlier version of GNU make.
172 * Native debugging on MS-Windows supports command-line redirection
174 Command-line arguments used for starting programs on MS-Windows can
175 now include redirection symbols supported by native Windows shells,
176 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
177 as "run", "start", and "set args", as well as the corresponding MI
180 * Support for thread names on MS-Windows.
182 GDB now catches and handles the special exception that programs
183 running on MS-Windows use to assign names to threads in the
186 * Support for Java programs compiled with gcj has been removed.
188 * User commands now accept an unlimited number of arguments.
189 Previously, only up to 10 was accepted.
191 * The "eval" command now expands user-defined command arguments.
193 This makes it easier to process a variable number of arguments:
198 eval "print $arg%d", $i
203 * Target descriptions can now describe registers for sparc32 and sparc64.
205 * GDB now supports DWARF version 5 (debug information format).
206 Its .debug_names index is not yet supported.
208 * New native configurations
210 FreeBSD/mips mips*-*-freebsd
214 Synopsys ARC arc*-*-elf32
215 FreeBSD/mips mips*-*-freebsd
217 * Removed targets and native configurations
219 Alpha running FreeBSD alpha*-*-freebsd*
220 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
225 Erases all the flash memory regions reported by the target.
227 maint print arc arc-instruction address
228 Print internal disassembler information about instruction at a given address.
232 set disassembler-options
233 show disassembler-options
234 Controls the passing of target specific information to the disassembler.
235 If it is necessary to specify more than one disassembler option then
236 multiple options can be placed together into a comma separated list.
237 The default value is the empty string. Currently, the only supported
238 targets are ARM, PowerPC and S/390.
243 Erases all the flash memory regions reported by the target. This is
244 equivalent to the CLI command flash-erase.
246 -file-list-shared-libraries
247 List the shared libraries in the program. This is
248 equivalent to the CLI command "info shared".
250 *** Changes in GDB 7.12
252 * GDB and GDBserver now build with a C++ compiler by default.
254 The --enable-build-with-cxx configure option is now enabled by
255 default. One must now explicitly configure with
256 --disable-build-with-cxx in order to build with a C compiler. This
257 option will be removed in a future release.
259 * GDBserver now supports recording btrace without maintaining an active
262 * GDB now supports a negative repeat count in the 'x' command to examine
263 memory backward from the given address. For example:
266 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
267 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
268 (gdb) x/-5i 0x0000000000400580
269 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
270 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
271 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
272 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
273 0x40057b <main(int, char**)+25>:
274 callq 0x400536 <Func1(int, char const*)>
276 * Fortran: Support structures with fields of dynamic types and
277 arrays of dynamic types.
279 * The symbol dumping maintenance commands have new syntax.
280 maint print symbols [-pc address] [--] [filename]
281 maint print symbols [-objfile objfile] [-source source] [--] [filename]
282 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
283 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
284 maint print msymbols [-objfile objfile] [--] [filename]
286 * GDB now supports multibit bitfields and enums in target register
289 * New Python-based convenience function $_as_string(val), which returns
290 the textual representation of a value. This function is especially
291 useful to obtain the text label of an enum value.
293 * Intel MPX bound violation handling.
295 Segmentation faults caused by a Intel MPX boundary violation
296 now display the kind of violation (upper or lower), the memory
297 address accessed and the memory bounds, along with the usual
298 signal received and code location.
302 Program received signal SIGSEGV, Segmentation fault
303 Upper bound violation while accessing address 0x7fffffffc3b3
304 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
305 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
307 * Rust language support.
308 GDB now supports debugging programs written in the Rust programming
309 language. See https://www.rust-lang.org/ for more information about
312 * Support for running interpreters on specified input/output devices
314 GDB now supports a new mechanism that allows frontends to provide
315 fully featured GDB console views, as a better alternative to
316 building such views on top of the "-interpreter-exec console"
317 command. See the new "new-ui" command below. With that command,
318 frontends can now start GDB in the traditional command-line mode
319 running in an embedded terminal emulator widget, and create a
320 separate MI interpreter running on a specified i/o device. In this
321 way, GDB handles line editing, history, tab completion, etc. in the
322 console all by itself, and the GUI uses the separate MI interpreter
323 for its own control and synchronization, invisible to the command
326 * The "catch syscall" command catches groups of related syscalls.
328 The "catch syscall" command now supports catching a group of related
329 syscalls using the 'group:' or 'g:' prefix.
334 skip -gfile file-glob-pattern
335 skip -function function
336 skip -rfunction regular-expression
337 A generalized form of the skip command, with new support for
338 glob-style file names and regular expressions for function names.
339 Additionally, a file spec and a function spec may now be combined.
341 maint info line-table REGEXP
342 Display the contents of GDB's internal line table data struture.
345 Run any GDB unit tests that were compiled in.
348 Start a new user interface instance running INTERP as interpreter,
349 using the TTY file for input/output.
353 ** gdb.Breakpoint objects have a new attribute "pending", which
354 indicates whether the breakpoint is pending.
355 ** Three new breakpoint-related events have been added:
356 gdb.breakpoint_created, gdb.breakpoint_modified, and
357 gdb.breakpoint_deleted.
360 Signal ("set") the given MS-Windows event object. This is used in
361 conjunction with the Windows JIT debugging (AeDebug) support, where
362 the OS suspends a crashing process until a debugger can attach to
363 it. Resuming the crashing process, in order to debug it, is done by
366 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
367 was added in GDBserver, including JIT compiling fast tracepoint's
368 conditional expression bytecode into native code.
370 * Support for various remote target protocols and ROM monitors has
373 target m32rsdi Remote M32R debugging over SDI
374 target mips MIPS remote debugging protocol
375 target pmon PMON ROM monitor
376 target ddb NEC's DDB variant of PMON for Vr4300
377 target rockhopper NEC RockHopper variant of PMON
378 target lsi LSI variant of PMO
380 * Support for tracepoints and fast tracepoints on powerpc-linux,
381 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
382 including JIT compiling fast tracepoint's conditional expression
383 bytecode into native code.
385 * MI async record =record-started now includes the method and format used for
386 recording. For example:
388 =record-started,thread-group="i1",method="btrace",format="bts"
390 * MI async record =thread-selected now includes the frame field. For example:
392 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
396 Andes NDS32 nds32*-*-elf
398 *** Changes in GDB 7.11
400 * GDB now supports debugging kernel-based threads on FreeBSD.
402 * Per-inferior thread numbers
404 Thread numbers are now per inferior instead of global. If you're
405 debugging multiple inferiors, GDB displays thread IDs using a
406 qualified INF_NUM.THR_NUM form. For example:
410 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
411 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
412 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
413 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
415 As consequence, thread numbers as visible in the $_thread
416 convenience variable and in Python's InferiorThread.num attribute
417 are no longer unique between inferiors.
419 GDB now maintains a second thread ID per thread, referred to as the
420 global thread ID, which is the new equivalent of thread numbers in
421 previous releases. See also $_gthread below.
423 For backwards compatibility, MI's thread IDs always refer to global
426 * Commands that accept thread IDs now accept the qualified
427 INF_NUM.THR_NUM form as well. For example:
430 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
433 * In commands that accept a list of thread IDs, you can now refer to
434 all threads of an inferior using a star wildcard. GDB accepts
435 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
436 refer to all threads of the current inferior. For example, "info
439 * You can use "info threads -gid" to display the global thread ID of
442 * The new convenience variable $_gthread holds the global number of
445 * The new convenience variable $_inferior holds the number of the
448 * GDB now displays the ID and name of the thread that hit a breakpoint
449 or received a signal, if your program is multi-threaded. For
452 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
453 Thread 1 "main" received signal SIGINT, Interrupt.
455 * Record btrace now supports non-stop mode.
457 * Support for tracepoints on aarch64-linux was added in GDBserver.
459 * The 'record instruction-history' command now indicates speculative execution
460 when using the Intel Processor Trace recording format.
462 * GDB now allows users to specify explicit locations, bypassing
463 the linespec parser. This feature is also available to GDB/MI
466 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
467 GDB now is able to debug both AArch64 applications and ARM applications
470 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
471 including JIT compiling fast tracepoint's conditional expression bytecode
474 * GDB now supports displaced stepping on AArch64 GNU/Linux.
476 * "info threads", "info inferiors", "info display", "info checkpoints"
477 and "maint info program-spaces" now list the corresponding items in
478 ascending ID order, for consistency with all other "info" commands.
480 * In Ada, the overloads selection menu has been enhanced to display the
481 parameter types and the return types for the matching overloaded subprograms.
485 maint set target-non-stop (on|off|auto)
486 maint show target-non-stop
487 Control whether GDB targets always operate in non-stop mode even if
488 "set non-stop" is "off". The default is "auto", meaning non-stop
489 mode is enabled if supported by the target.
491 maint set bfd-sharing
492 maint show bfd-sharing
493 Control the reuse of bfd objects.
497 Control display of debugging info regarding bfd caching.
501 Control display of debugging info regarding FreeBSD threads.
503 set remote multiprocess-extensions-packet
504 show remote multiprocess-extensions-packet
505 Set/show the use of the remote protocol multiprocess extensions.
507 set remote thread-events
508 show remote thread-events
509 Set/show the use of thread create/exit events.
511 set ada print-signatures on|off
512 show ada print-signatures"
513 Control whether parameter types and return types are displayed in overloads
514 selection menus. It is activaled (@code{on}) by default.
518 Controls the maximum size of memory, in bytes, that GDB will
519 allocate for value contents. Prevents incorrect programs from
520 causing GDB to allocate overly large buffers. Default is 64k.
522 * The "disassemble" command accepts a new modifier: /s.
523 It prints mixed source+disassembly like /m with two differences:
524 - disassembled instructions are now printed in program order, and
525 - and source for all relevant files is now printed.
526 The "/m" option is now considered deprecated: its "source-centric"
527 output hasn't proved useful in practice.
529 * The "record instruction-history" command accepts a new modifier: /s.
530 It behaves exactly like /m and prints mixed source+disassembly.
532 * The "set scheduler-locking" command supports a new mode "replay".
533 It behaves like "off" in record mode and like "on" in replay mode.
535 * Support for various ROM monitors has been removed:
537 target dbug dBUG ROM monitor for Motorola ColdFire
538 target picobug Motorola picobug monitor
539 target dink32 DINK32 ROM monitor for PowerPC
540 target m32r Renesas M32R/D ROM monitor
541 target mon2000 mon2000 ROM monitor
542 target ppcbug PPCBUG ROM monitor for PowerPC
544 * Support for reading/writing memory and extracting values on architectures
545 whose memory is addressable in units of any integral multiple of 8 bits.
550 Indicates that an exec system call was executed.
552 exec-events feature in qSupported
553 The qSupported packet allows GDB to request support for exec
554 events using the new 'gdbfeature' exec-event, and the qSupported
555 response can contain the corresponding 'stubfeature'. Set and
556 show commands can be used to display whether these features are enabled.
559 Equivalent to interrupting with the ^C character, but works in
562 thread created stop reason (T05 create:...)
563 Indicates that the thread was just created and is stopped at entry.
565 thread exit stop reply (w exitcode;tid)
566 Indicates that the thread has terminated.
569 Enables/disables thread create and exit event reporting. For
570 example, this is used in non-stop mode when GDB stops a set of
571 threads and synchronously waits for the their corresponding stop
572 replies. Without exit events, if one of the threads exits, GDB
573 would hang forever not knowing that it should no longer expect a
574 stop for that same thread.
577 Indicates that there are no resumed threads left in the target (all
578 threads are stopped). The remote stub reports support for this stop
579 reply to GDB's qSupported query.
582 Enables/disables catching syscalls from the inferior process.
583 The remote stub reports support for this packet to GDB's qSupported query.
585 syscall_entry stop reason
586 Indicates that a syscall was just called.
588 syscall_return stop reason
589 Indicates that a syscall just returned.
591 * Extended-remote exec events
593 ** GDB now has support for exec events on extended-remote Linux targets.
594 For such targets with Linux kernels 2.5.46 and later, this enables
595 follow-exec-mode and exec catchpoints.
597 set remote exec-event-feature-packet
598 show remote exec-event-feature-packet
599 Set/show the use of the remote exec event feature.
601 * Thread names in remote protocol
603 The reply to qXfer:threads:read may now include a name attribute for each
606 * Target remote mode fork and exec events
608 ** GDB now has support for fork and exec events on target remote mode
609 Linux targets. For such targets with Linux kernels 2.5.46 and later,
610 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
611 fork and exec catchpoints.
613 * Remote syscall events
615 ** GDB now has support for catch syscall on remote Linux targets,
616 currently enabled on x86/x86_64 architectures.
618 set remote catch-syscall-packet
619 show remote catch-syscall-packet
620 Set/show the use of the remote catch syscall feature.
624 ** The -var-set-format command now accepts the zero-hexadecimal
625 format. It outputs data in hexadecimal format with zero-padding on the
630 ** gdb.InferiorThread objects have a new attribute "global_num",
631 which refers to the thread's global thread ID. The existing
632 "num" attribute now refers to the thread's per-inferior number.
633 See "Per-inferior thread numbers" above.
634 ** gdb.InferiorThread objects have a new attribute "inferior", which
635 is the Inferior object the thread belongs to.
637 *** Changes in GDB 7.10
639 * Support for process record-replay and reverse debugging on aarch64*-linux*
640 targets has been added. GDB now supports recording of A64 instruction set
641 including advance SIMD instructions.
643 * Support for Sun's version of the "stabs" debug file format has been removed.
645 * GDB now honors the content of the file /proc/PID/coredump_filter
646 (PID is the process ID) on GNU/Linux systems. This file can be used
647 to specify the types of memory mappings that will be included in a
648 corefile. For more information, please refer to the manual page of
649 "core(5)". GDB also has a new command: "set use-coredump-filter
650 on|off". It allows to set whether GDB will read the content of the
651 /proc/PID/coredump_filter file when generating a corefile.
653 * The "info os" command on GNU/Linux can now display information on
655 "info os cpus" Listing of all cpus/cores on the system
657 * GDB has two new commands: "set serial parity odd|even|none" and
658 "show serial parity". These allows to set or show parity for the
661 * The "info source" command now displays the producer string if it was
662 present in the debug info. This typically includes the compiler version
663 and may include things like its command line arguments.
665 * The "info dll", an alias of the "info sharedlibrary" command,
666 is now available on all platforms.
668 * Directory names supplied to the "set sysroot" commands may be
669 prefixed with "target:" to tell GDB to access shared libraries from
670 the target system, be it local or remote. This replaces the prefix
671 "remote:". The default sysroot has been changed from "" to
672 "target:". "remote:" is automatically converted to "target:" for
673 backward compatibility.
675 * The system root specified by "set sysroot" will be prepended to the
676 filename of the main executable (if reported to GDB as absolute by
677 the operating system) when starting processes remotely, and when
678 attaching to already-running local or remote processes.
680 * GDB now supports automatic location and retrieval of executable
681 files from remote targets. Remote debugging can now be initiated
682 using only a "target remote" or "target extended-remote" command
683 (no "set sysroot" or "file" commands are required). See "New remote
686 * The "dump" command now supports verilog hex format.
688 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
690 * On GNU/Linux, GDB and gdbserver are now able to access executable
691 and shared library files without a "set sysroot" command when
692 attaching to processes running in different mount namespaces from
693 the debugger. This makes it possible to attach to processes in
694 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
695 See "New remote packets" below.
697 * The "tui reg" command now provides completion for all of the
698 available register groups, including target specific groups.
700 * The HISTSIZE environment variable is no longer read when determining
701 the size of GDB's command history. GDB now instead reads the dedicated
702 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
703 disables truncation of command history. Non-numeric values of GDBHISTSIZE
708 ** Memory ports can now be unbuffered.
712 ** gdb.Objfile objects have a new attribute "username",
713 which is the name of the objfile as specified by the user,
714 without, for example, resolving symlinks.
715 ** You can now write frame unwinders in Python.
716 ** gdb.Type objects have a new method "optimized_out",
717 returning optimized out gdb.Value instance of this type.
718 ** gdb.Value objects have new methods "reference_value" and
719 "const_value" which return a reference to the value and a
720 "const" version of the value respectively.
724 maint print symbol-cache
725 Print the contents of the symbol cache.
727 maint print symbol-cache-statistics
728 Print statistics of symbol cache usage.
730 maint flush-symbol-cache
731 Flush the contents of the symbol cache.
735 Start branch trace recording using Branch Trace Store (BTS) format.
738 Evaluate expression by using the compiler and print result.
742 Explicit commands for enabling and disabling tui mode.
745 set mpx bound on i386 and amd64
746 Support for bound table investigation on Intel MPX enabled applications.
750 Start branch trace recording using Intel Processor Trace format.
753 Print information about branch tracing internals.
755 maint btrace packet-history
756 Print the raw branch tracing data.
758 maint btrace clear-packet-history
759 Discard the stored raw branch tracing data.
762 Discard all branch tracing data. It will be fetched and processed
763 anew by the next "record" command.
768 Renamed from "set debug dwarf2-die".
770 Renamed from "show debug dwarf2-die".
773 Renamed from "set debug dwarf2-read".
774 show debug dwarf-read
775 Renamed from "show debug dwarf2-read".
777 maint set dwarf always-disassemble
778 Renamed from "maint set dwarf2 always-disassemble".
779 maint show dwarf always-disassemble
780 Renamed from "maint show dwarf2 always-disassemble".
782 maint set dwarf max-cache-age
783 Renamed from "maint set dwarf2 max-cache-age".
784 maint show dwarf max-cache-age
785 Renamed from "maint show dwarf2 max-cache-age".
788 show debug dwarf-line
789 Control display of debugging info regarding DWARF line processing.
793 Set the maximum number of candidates to be considered during
794 completion. The default value is 200. This limit allows GDB
795 to avoid generating large completion lists, the computation of
796 which can cause the debugger to become temporarily unresponsive.
798 set history remove-duplicates
799 show history remove-duplicates
800 Control the removal of duplicate history entries.
802 maint set symbol-cache-size
803 maint show symbol-cache-size
804 Control the size of the symbol cache.
806 set|show record btrace bts buffer-size
807 Set and show the size of the ring buffer used for branch tracing in
809 The obtained size may differ from the requested size. Use "info
810 record" to see the obtained buffer size.
812 set debug linux-namespaces
813 show debug linux-namespaces
814 Control display of debugging info regarding Linux namespaces.
816 set|show record btrace pt buffer-size
817 Set and show the size of the ring buffer used for branch tracing in
818 Intel Processor Trace format.
819 The obtained size may differ from the requested size. Use "info
820 record" to see the obtained buffer size.
822 maint set|show btrace pt skip-pad
823 Set and show whether PAD packets are skipped when computing the
826 * The command 'thread apply all' can now support new option '-ascending'
827 to call its specified command for all threads in ascending order.
829 * Python/Guile scripting
831 ** GDB now supports auto-loading of Python/Guile scripts contained in the
832 special section named `.debug_gdb_scripts'.
836 qXfer:btrace-conf:read
837 Return the branch trace configuration for the current thread.
839 Qbtrace-conf:bts:size
840 Set the requested ring buffer size for branch tracing in BTS format.
843 Enable Intel Procesor Trace-based branch tracing for the current
844 process. The remote stub reports support for this packet to GDB's
848 Set the requested ring buffer size for branch tracing in Intel Processor
852 Indicates a memory breakpoint instruction was executed, irrespective
853 of whether it was GDB that planted the breakpoint or the breakpoint
854 is hardcoded in the program. This is required for correct non-stop
858 Indicates the target stopped for a hardware breakpoint. This is
859 required for correct non-stop mode operation.
862 Return information about files on the remote system.
865 Return the full absolute name of the file that was executed to
866 create a process running on the remote system.
869 Select the filesystem on which vFile: operations with filename
870 arguments will operate. This is required for GDB to be able to
871 access files on remote targets where the remote stub does not
872 share a common filesystem with the inferior(s).
875 Indicates that a fork system call was executed.
878 Indicates that a vfork system call was executed.
880 vforkdone stop reason
881 Indicates that a vfork child of the specified process has executed
882 an exec or exit, allowing the vfork parent to resume execution.
884 fork-events and vfork-events features in qSupported
885 The qSupported packet allows GDB to request support for fork and
886 vfork events using new 'gdbfeatures' fork-events and vfork-events,
887 and the qSupported response can contain the corresponding
888 'stubfeatures'. Set and show commands can be used to display
889 whether these features are enabled.
891 * Extended-remote fork events
893 ** GDB now has support for fork events on extended-remote Linux
894 targets. For targets with Linux kernels 2.5.60 and later, this
895 enables follow-fork-mode and detach-on-fork for both fork and
896 vfork, as well as fork and vfork catchpoints.
898 * The info record command now shows the recording format and the
899 branch tracing configuration for the current thread when using
900 the btrace record target.
901 For the BTS format, it shows the ring buffer size.
903 * GDB now has support for DTrace USDT (Userland Static Defined
904 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
906 * GDB now supports access to vector registers on S/390 GNU/Linux
909 * Removed command line options
911 -xdb HP-UX XDB compatibility mode.
913 * Removed targets and native configurations
915 HP/PA running HP-UX hppa*-*-hpux*
916 Itanium running HP-UX ia64-*-hpux*
918 * New configure options
921 This configure option allows the user to build GDB with support for
922 Intel Processor Trace (default: auto). This requires libipt.
924 --with-libipt-prefix=PATH
925 Specify the path to the version of libipt that GDB should use.
926 $PATH/include should contain the intel-pt.h header and
927 $PATH/lib should contain the libipt.so library.
929 *** Changes in GDB 7.9.1
933 ** Xmethods can now specify a result type.
935 *** Changes in GDB 7.9
937 * GDB now supports hardware watchpoints on x86 GNU Hurd.
941 ** You can now access frame registers from Python scripts.
942 ** New attribute 'producer' for gdb.Symtab objects.
943 ** gdb.Objfile objects have a new attribute "progspace",
944 which is the gdb.Progspace object of the containing program space.
945 ** gdb.Objfile objects have a new attribute "owner".
946 ** gdb.Objfile objects have a new attribute "build_id",
947 which is the build ID generated when the file was built.
948 ** gdb.Objfile objects have a new method "add_separate_debug_file".
949 ** A new event "gdb.clear_objfiles" has been added, triggered when
950 selecting a new file to debug.
951 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
952 ** New function gdb.lookup_objfile.
954 New events which are triggered when GDB modifies the state of the
957 ** gdb.events.inferior_call_pre: Function call is about to be made.
958 ** gdb.events.inferior_call_post: Function call has just been made.
959 ** gdb.events.memory_changed: A memory location has been altered.
960 ** gdb.events.register_changed: A register has been altered.
962 * New Python-based convenience functions:
964 ** $_caller_is(name [, number_of_frames])
965 ** $_caller_matches(regexp [, number_of_frames])
966 ** $_any_caller_is(name [, number_of_frames])
967 ** $_any_caller_matches(regexp [, number_of_frames])
969 * GDB now supports the compilation and injection of source code into
970 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
971 to compile the source code to object code, and if successful, inject
972 and execute that code within the current context of the inferior.
973 Currently the C language is supported. The commands used to
974 interface with this new feature are:
976 compile code [-raw|-r] [--] [source code]
977 compile file [-raw|-r] filename
981 demangle [-l language] [--] name
982 Demangle "name" in the specified language, or the current language
983 if elided. This command is renamed from the "maint demangle" command.
984 The latter is kept as a no-op to avoid "maint demangle" being interpreted
985 as "maint demangler-warning".
987 queue-signal signal-name-or-number
988 Queue a signal to be delivered to the thread when it is resumed.
990 add-auto-load-scripts-directory directory
991 Add entries to the list of directories from which to load auto-loaded
994 maint print user-registers
995 List all currently available "user" registers.
997 compile code [-r|-raw] [--] [source code]
998 Compile, inject, and execute in the inferior the executable object
999 code produced by compiling the provided source code.
1001 compile file [-r|-raw] filename
1002 Compile and inject into the inferior the executable object code
1003 produced by compiling the source code stored in the filename
1006 * On resume, GDB now always passes the signal the program had stopped
1007 for to the thread the signal was sent to, even if the user changed
1008 threads before resuming. Previously GDB would often (but not
1009 always) deliver the signal to the thread that happens to be current
1012 * Conversely, the "signal" command now consistently delivers the
1013 requested signal to the current thread. GDB now asks for
1014 confirmation if the program had stopped for a signal and the user
1015 switched threads meanwhile.
1017 * "breakpoint always-inserted" modes "off" and "auto" merged.
1019 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1020 won't remove breakpoints from the target until all threads stop,
1021 even in non-stop mode. The "auto" mode has been removed, and "off"
1022 is now the default mode.
1026 set debug symbol-lookup
1027 show debug symbol-lookup
1028 Control display of debugging info regarding symbol lookup.
1032 ** The -list-thread-groups command outputs an exit-code field for
1033 inferiors that have exited.
1037 MIPS SDE mips*-sde*-elf*
1041 Support for these obsolete configurations has been removed.
1043 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1044 SGI Irix-5.x mips-*-irix5*
1045 SGI Irix-6.x mips-*-irix6*
1046 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1047 VAX running Ultrix vax-*-ultrix*
1049 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1050 and "assf"), have been removed. Use the "sharedlibrary" command, or
1051 its alias "share", instead.
1053 *** Changes in GDB 7.8
1055 * New command line options
1058 This is an alias for the --data-directory option.
1060 * GDB supports printing and modifying of variable length automatic arrays
1061 as specified in ISO C99.
1063 * The ARM simulator now supports instruction level tracing
1064 with or without disassembly.
1068 GDB now has support for scripting using Guile. Whether this is
1069 available is determined at configure time.
1070 Guile version 2.0 or greater is required.
1071 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1073 * New commands (for set/show, see "New options" below)
1077 Invoke CODE by passing it to the Guile interpreter.
1081 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1083 info auto-load guile-scripts [regexp]
1084 Print the list of automatically loaded Guile scripts.
1086 * The source command is now capable of sourcing Guile scripts.
1087 This feature is dependent on the debugger being built with Guile support.
1091 set print symbol-loading (off|brief|full)
1092 show print symbol-loading
1093 Control whether to print informational messages when loading symbol
1094 information for a file. The default is "full", but when debugging
1095 programs with large numbers of shared libraries the amount of output
1096 becomes less useful.
1098 set guile print-stack (none|message|full)
1099 show guile print-stack
1100 Show a stack trace when an error is encountered in a Guile script.
1102 set auto-load guile-scripts (on|off)
1103 show auto-load guile-scripts
1104 Control auto-loading of Guile script files.
1106 maint ada set ignore-descriptive-types (on|off)
1107 maint ada show ignore-descriptive-types
1108 Control whether the debugger should ignore descriptive types in Ada
1109 programs. The default is not to ignore the descriptive types. See
1110 the user manual for more details on descriptive types and the intended
1111 usage of this option.
1113 set auto-connect-native-target
1115 Control whether GDB is allowed to automatically connect to the
1116 native target for the run, attach, etc. commands when not connected
1117 to any target yet. See also "target native" below.
1119 set record btrace replay-memory-access (read-only|read-write)
1120 show record btrace replay-memory-access
1121 Control what memory accesses are allowed during replay.
1123 maint set target-async (on|off)
1124 maint show target-async
1125 This controls whether GDB targets operate in synchronous or
1126 asynchronous mode. Normally the default is asynchronous, if it is
1127 available; but this can be changed to more easily debug problems
1128 occurring only in synchronous mode.
1130 set mi-async (on|off)
1132 Control whether MI asynchronous mode is preferred. This supersedes
1133 "set target-async" of previous GDB versions.
1135 * "set target-async" is deprecated as a CLI option and is now an alias
1136 for "set mi-async" (only puts MI into async mode).
1138 * Background execution commands (e.g., "c&", "s&", etc.) are now
1139 possible ``out of the box'' if the target supports them. Previously
1140 the user would need to explicitly enable the possibility with the
1141 "set target-async on" command.
1143 * New features in the GDB remote stub, GDBserver
1145 ** New option --debug-format=option1[,option2,...] allows one to add
1146 additional text to each output. At present only timestamps
1147 are supported: --debug-format=timestamps.
1148 Timestamps can also be turned on with the
1149 "monitor set debug-format timestamps" command from GDB.
1151 * The 'record instruction-history' command now starts counting instructions
1152 at one. This also affects the instruction ranges reported by the
1153 'record function-call-history' command when given the /i modifier.
1155 * The command 'record function-call-history' supports a new modifier '/c' to
1156 indent the function names based on their call stack depth.
1157 The fields for the '/i' and '/l' modifier have been reordered.
1158 The source line range is now prefixed with 'at'.
1159 The instruction range is now prefixed with 'inst'.
1160 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1161 "record instruction-history" and "list" commands.
1163 * The ranges given as arguments to the 'record function-call-history' and
1164 'record instruction-history' commands are now inclusive.
1166 * The btrace record target now supports the 'record goto' command.
1167 For locations inside the execution trace, the back trace is computed
1168 based on the information stored in the execution trace.
1170 * The btrace record target supports limited reverse execution and replay.
1171 The target does not record data and therefore does not allow reading
1172 memory or registers.
1174 * The "catch syscall" command now works on s390*-linux* targets.
1176 * The "compare-sections" command is no longer specific to target
1177 remote. It now works with all targets.
1179 * All native targets are now consistently called "native".
1180 Consequently, the "target child", "target GNU", "target djgpp",
1181 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1182 commands have been replaced with "target native". The QNX/NTO port
1183 leaves the "procfs" target in place and adds a "native" target for
1184 consistency with other ports. The impact on users should be minimal
1185 as these commands previously either throwed an error, or were
1186 no-ops. The target's name is visible in the output of the following
1187 commands: "help target", "info target", "info files", "maint print
1190 * The "target native" command now connects to the native target. This
1191 can be used to launch native programs even when "set
1192 auto-connect-native-target" is set to off.
1194 * GDB now supports access to Intel MPX registers on GNU/Linux.
1196 * Support for Intel AVX-512 registers on GNU/Linux.
1197 Support displaying and modifying Intel AVX-512 registers
1198 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1200 * New remote packets
1202 qXfer:btrace:read's annex
1203 The qXfer:btrace:read packet supports a new annex 'delta' to read
1204 branch trace incrementally.
1208 ** Valid Python operations on gdb.Value objects representing
1209 structs/classes invoke the corresponding overloaded operators if
1211 ** New `Xmethods' feature in the Python API. Xmethods are
1212 additional methods or replacements for existing methods of a C++
1213 class. This feature is useful for those cases where a method
1214 defined in C++ source code could be inlined or optimized out by
1215 the compiler, making it unavailable to GDB.
1218 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1220 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1221 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1222 its alias "share", instead.
1224 * The commands "set remotebaud" and "show remotebaud" are no longer
1225 supported. Use "set serial baud" and "show serial baud" (respectively)
1230 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1231 target-async". The latter is left as a deprecated alias of the
1232 former for backward compatibility. If the target supports it,
1233 CLI background execution commands are now always possible by
1234 default, independently of whether the frontend stated a
1235 preference for asynchronous execution with "-gdb-set mi-async".
1236 Previously "-gdb-set target-async off" affected both MI execution
1237 commands and CLI execution commands.
1239 *** Changes in GDB 7.7
1241 * Improved support for process record-replay and reverse debugging on
1242 arm*-linux* targets. Support for thumb32 and syscall instruction
1243 recording has been added.
1245 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1247 * GDB now supports Fission DWP file format version 2.
1248 http://gcc.gnu.org/wiki/DebugFission
1250 * New convenience function "$_isvoid", to check whether an expression
1251 is void. A void expression is an expression where the type of the
1252 result is "void". For example, some convenience variables may be
1253 "void" when evaluated (e.g., "$_exitcode" before the execution of
1254 the program being debugged; or an undefined convenience variable).
1255 Another example, when calling a function whose return type is
1258 * The "maintenance print objfiles" command now takes an optional regexp.
1260 * The "catch syscall" command now works on arm*-linux* targets.
1262 * GDB now consistently shows "<not saved>" when printing values of
1263 registers the debug info indicates have not been saved in the frame
1264 and there's nowhere to retrieve them from
1265 (callee-saved/call-clobbered registers):
1270 (gdb) info registers rax
1273 Before, the former would print "<optimized out>", and the latter
1274 "*value not available*".
1276 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1281 ** Frame filters and frame decorators have been added.
1282 ** Temporary breakpoints are now supported.
1283 ** Line tables representation has been added.
1284 ** New attribute 'parent_type' for gdb.Field objects.
1285 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1286 ** New attribute 'name' for gdb.Type objects.
1290 Nios II ELF nios2*-*-elf
1291 Nios II GNU/Linux nios2*-*-linux
1292 Texas Instruments MSP430 msp430*-*-elf
1294 * Removed native configurations
1296 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1297 been removed. ELF variants of these configurations are kept supported.
1299 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1300 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1301 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1302 i[34567]86-*-openbsd3.[0-3]
1303 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1304 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1305 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1309 Like "catch throw", but catches a re-thrown exception.
1310 maint check-psymtabs
1311 Renamed from old "maint check-symtabs".
1313 Perform consistency checks on symtabs.
1314 maint expand-symtabs
1315 Expand symtabs matching an optional regexp.
1318 Display the details of GDB configure-time options.
1320 maint set|show per-command
1321 maint set|show per-command space
1322 maint set|show per-command time
1323 maint set|show per-command symtab
1324 Enable display of per-command gdb resource usage.
1326 remove-symbol-file FILENAME
1327 remove-symbol-file -a ADDRESS
1328 Remove a symbol file added via add-symbol-file. The file to remove
1329 can be identified by its filename or by an address that lies within
1330 the boundaries of this symbol file in memory.
1333 info exceptions REGEXP
1334 Display the list of Ada exceptions defined in the program being
1335 debugged. If provided, only the exceptions whose names match REGEXP
1340 set debug symfile off|on
1342 Control display of debugging info regarding reading symbol files and
1343 symbol tables within those files
1345 set print raw frame-arguments
1346 show print raw frame-arguments
1347 Set/show whether to print frame arguments in raw mode,
1348 disregarding any defined pretty-printers.
1350 set remote trace-status-packet
1351 show remote trace-status-packet
1352 Set/show the use of remote protocol qTStatus packet.
1356 Control display of debugging messages related to Nios II targets.
1360 Control whether target-assisted range stepping is enabled.
1362 set startup-with-shell
1363 show startup-with-shell
1364 Specifies whether Unix child processes are started via a shell or
1369 Use the target memory cache for accesses to the code segment. This
1370 improves performance of remote debugging (particularly disassembly).
1372 * You can now use a literal value 'unlimited' for options that
1373 interpret 0 or -1 as meaning "unlimited". E.g., "set
1374 trace-buffer-size unlimited" is now an alias for "set
1375 trace-buffer-size -1" and "set height unlimited" is now an alias for
1378 * The "set debug symtab-create" debugging option of GDB has been changed to
1379 accept a verbosity level. 0 means "off", 1 provides basic debugging
1380 output, and values of 2 or greater provides more verbose output.
1382 * New command-line options
1384 Display the details of GDB configure-time options.
1386 * The command 'tsave' can now support new option '-ctf' to save trace
1387 buffer in Common Trace Format.
1389 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1392 * GDB now implements the the C++ 'typeid' operator.
1394 * The new convenience variable $_exception holds the exception being
1395 thrown or caught at an exception-related catchpoint.
1397 * The exception-related catchpoints, like "catch throw", now accept a
1398 regular expression which can be used to filter exceptions by type.
1400 * The new convenience variable $_exitsignal is automatically set to
1401 the terminating signal number when the program being debugged dies
1402 due to an uncaught signal.
1406 ** All MI commands now accept an optional "--language" option.
1407 Support for this feature can be verified by using the "-list-features"
1408 command, which should contain "language-option".
1410 ** The new command -info-gdb-mi-command allows the user to determine
1411 whether a GDB/MI command is supported or not.
1413 ** The "^error" result record returned when trying to execute an undefined
1414 GDB/MI command now provides a variable named "code" whose content is the
1415 "undefined-command" error code. Support for this feature can be verified
1416 by using the "-list-features" command, which should contain
1417 "undefined-command-error-code".
1419 ** The -trace-save MI command can optionally save trace buffer in Common
1422 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1424 ** The command -data-list-register-values now accepts an optional
1425 "--skip-unavailable" option. When used, only the available registers
1428 ** The new command -trace-frame-collected dumps collected variables,
1429 computed expressions, tvars, memory and registers in a traceframe.
1431 ** The commands -stack-list-locals, -stack-list-arguments and
1432 -stack-list-variables now accept an option "--skip-unavailable".
1433 When used, only the available locals or arguments are displayed.
1435 ** The -exec-run command now accepts an optional "--start" option.
1436 When used, the command follows the same semantics as the "start"
1437 command, stopping the program's execution at the start of its
1438 main subprogram. Support for this feature can be verified using
1439 the "-list-features" command, which should contain
1440 "exec-run-start-option".
1442 ** The new commands -catch-assert and -catch-exceptions insert
1443 catchpoints stopping the program when Ada exceptions are raised.
1445 ** The new command -info-ada-exceptions provides the equivalent of
1446 the new "info exceptions" command.
1448 * New system-wide configuration scripts
1449 A GDB installation now provides scripts suitable for use as system-wide
1450 configuration scripts for the following systems:
1454 * GDB now supports target-assigned range stepping with remote targets.
1455 This improves the performance of stepping source lines by reducing
1456 the number of control packets from/to GDB. See "New remote packets"
1459 * GDB now understands the element 'tvar' in the XML traceframe info.
1460 It has the id of the collected trace state variables.
1462 * On S/390 targets that provide the transactional-execution feature,
1463 the program interruption transaction diagnostic block (TDB) is now
1464 represented as a number of additional "registers" in GDB.
1466 * New remote packets
1470 The vCont packet supports a new 'r' action, that tells the remote
1471 stub to step through an address range itself, without GDB
1472 involvemement at each single-step.
1474 qXfer:libraries-svr4:read's annex
1475 The previously unused annex of the qXfer:libraries-svr4:read packet
1476 is now used to support passing an argument list. The remote stub
1477 reports support for this argument list to GDB's qSupported query.
1478 The defined arguments are "start" and "prev", used to reduce work
1479 necessary for library list updating, resulting in significant
1482 * New features in the GDB remote stub, GDBserver
1484 ** GDBserver now supports target-assisted range stepping. Currently
1485 enabled on x86/x86_64 GNU/Linux targets.
1487 ** GDBserver now adds element 'tvar' in the XML in the reply to
1488 'qXfer:traceframe-info:read'. It has the id of the collected
1489 trace state variables.
1491 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1494 * New 'z' formatter for printing and examining memory, this displays the
1495 value as hexadecimal zero padded on the left to the size of the type.
1497 * GDB can now use Windows x64 unwinding data.
1499 * The "set remotebaud" command has been replaced by "set serial baud".
1500 Similarly, "show remotebaud" has been replaced by "show serial baud".
1501 The "set remotebaud" and "show remotebaud" commands are still available
1502 to provide backward compatibility with older versions of GDB.
1504 *** Changes in GDB 7.6
1506 * Target record has been renamed to record-full.
1507 Record/replay is now enabled with the "record full" command.
1508 This also affects settings that are associated with full record/replay
1509 that have been moved from "set/show record" to "set/show record full":
1511 set|show record full insn-number-max
1512 set|show record full stop-at-limit
1513 set|show record full memory-query
1515 * A new record target "record-btrace" has been added. The new target
1516 uses hardware support to record the control-flow of a process. It
1517 does not support replaying the execution, but it implements the
1518 below new commands for investigating the recorded execution log.
1519 This new recording method can be enabled using:
1523 The "record-btrace" target is only available on Intel Atom processors
1524 and requires a Linux kernel 2.6.32 or later.
1526 * Two new commands have been added for record/replay to give information
1527 about the recorded execution without having to replay the execution.
1528 The commands are only supported by "record btrace".
1530 record instruction-history prints the execution history at
1531 instruction granularity
1533 record function-call-history prints the execution history at
1534 function granularity
1536 * New native configurations
1538 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
1539 FreeBSD/powerpc powerpc*-*-freebsd
1540 x86_64/Cygwin x86_64-*-cygwin*
1541 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
1545 ARM AArch64 aarch64*-*-elf
1546 ARM AArch64 GNU/Linux aarch64*-*-linux
1547 Lynx 178 PowerPC powerpc-*-lynx*178
1548 x86_64/Cygwin x86_64-*-cygwin*
1549 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
1551 * If the configured location of system.gdbinit file (as given by the
1552 --with-system-gdbinit option at configure time) is in the
1553 data-directory (as specified by --with-gdb-datadir at configure
1554 time) or in one of its subdirectories, then GDB will look for the
1555 system-wide init file in the directory specified by the
1556 --data-directory command-line option.
1558 * New command line options:
1560 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
1561 other initialization files, unlike -nx which disables all of them.
1563 * Removed command line options
1565 -epoch This was used by the gdb mode in Epoch, an ancient fork of
1568 * The 'ptype' and 'whatis' commands now accept an argument to control
1571 * 'info proc' now works on some core files.
1575 ** Vectors can be created with gdb.Type.vector.
1577 ** Python's atexit.register now works in GDB.
1579 ** Types can be pretty-printed via a Python API.
1581 ** Python 3 is now supported (in addition to Python 2.4 or later)
1583 ** New class gdb.Architecture exposes GDB's internal representation
1584 of architecture in the Python API.
1586 ** New method Frame.architecture returns the gdb.Architecture object
1587 corresponding to the frame's architecture.
1589 * New Python-based convenience functions:
1591 ** $_memeq(buf1, buf2, length)
1592 ** $_streq(str1, str2)
1594 ** $_regex(str, regex)
1596 * The 'cd' command now defaults to using '~' (the home directory) if not
1599 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
1600 default for GCC since November 2000.
1602 * The command 'forward-search' can now be abbreviated as 'fo'.
1604 * The command 'info tracepoints' can now display 'installed on target'
1605 or 'not installed on target' for each non-pending location of tracepoint.
1607 * New configure options
1609 --enable-libmcheck/--disable-libmcheck
1610 By default, development versions are built with -lmcheck on hosts
1611 that support it, in order to help track memory corruption issues.
1612 Release versions, on the other hand, are built without -lmcheck
1613 by default. The --enable-libmcheck/--disable-libmcheck configure
1614 options allow the user to override that default.
1615 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
1616 This configure option allows the user to build GDB with
1617 libbabeltrace using which GDB can read Common Trace Format data.
1619 * New commands (for set/show, see "New options" below)
1622 Catch signals. This is similar to "handle", but allows commands and
1623 conditions to be attached.
1626 List the BFDs known to GDB.
1628 python-interactive [command]
1630 Start a Python interactive prompt, or evaluate the optional command
1631 and print the result of expressions.
1634 "py" is a new alias for "python".
1636 enable type-printer [name]...
1637 disable type-printer [name]...
1638 Enable or disable type printers.
1642 ** For the Renesas Super-H architecture, the "regs" command has been removed
1643 (has been deprecated in GDB 7.5), and "info all-registers" should be used
1648 set print type methods (on|off)
1649 show print type methods
1650 Control whether method declarations are displayed by "ptype".
1651 The default is to show them.
1653 set print type typedefs (on|off)
1654 show print type typedefs
1655 Control whether typedef definitions are displayed by "ptype".
1656 The default is to show them.
1658 set filename-display basename|relative|absolute
1659 show filename-display
1660 Control the way in which filenames is displayed.
1661 The default is "relative", which preserves previous behavior.
1663 set trace-buffer-size
1664 show trace-buffer-size
1665 Request target to change the size of trace buffer.
1667 set remote trace-buffer-size-packet auto|on|off
1668 show remote trace-buffer-size-packet
1669 Control the use of the remote protocol `QTBuffer:size' packet.
1673 Control display of debugging messages related to ARM AArch64.
1676 set debug coff-pe-read
1677 show debug coff-pe-read
1678 Control display of debugging messages related to reading of COFF/PE
1683 Control display of debugging messages related to Mach-O symbols
1686 set debug notification
1687 show debug notification
1688 Control display of debugging info for async remote notification.
1692 ** Command parameter changes are now notified using new async record
1693 "=cmd-param-changed".
1694 ** Trace frame changes caused by command "tfind" are now notified using
1695 new async record "=traceframe-changed".
1696 ** The creation, deletion and modification of trace state variables
1697 are now notified using new async records "=tsv-created",
1698 "=tsv-deleted" and "=tsv-modified".
1699 ** The start and stop of process record are now notified using new
1700 async record "=record-started" and "=record-stopped".
1701 ** Memory changes are now notified using new async record
1703 ** The data-disassemble command response will include a "fullname" field
1704 containing the absolute file name when source has been requested.
1705 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
1706 command, to allow pattern filling of memory areas.
1707 ** New commands "-catch-load"/"-catch-unload" added for intercepting
1708 library load/unload events.
1709 ** The response to breakpoint commands and breakpoint async records
1710 includes an "installed" field containing a boolean state about each
1711 non-pending tracepoint location is whether installed on target or not.
1712 ** Output of the "-trace-status" command includes a "trace-file" field
1713 containing the name of the trace file being examined. This field is
1714 optional, and only present when examining a trace file.
1715 ** The "fullname" field is now always present along with the "file" field,
1716 even if the file cannot be found by GDB.
1718 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
1719 You must have the LZMA library available when configuring GDB for this
1720 feature to be enabled. For more information, see:
1721 http://fedoraproject.org/wiki/Features/MiniDebugInfo
1723 * New remote packets
1726 Set the size of trace buffer. The remote stub reports support for this
1727 packet to gdb's qSupported query.
1730 Enable Branch Trace Store (BTS)-based branch tracing for the current
1731 thread. The remote stub reports support for this packet to gdb's
1735 Disable branch tracing for the current thread. The remote stub reports
1736 support for this packet to gdb's qSupported query.
1739 Read the traced branches for the current thread. The remote stub
1740 reports support for this packet to gdb's qSupported query.
1742 *** Changes in GDB 7.5
1744 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
1745 for more x32 ABI info.
1747 * GDB now supports access to MIPS DSP registers on Linux targets.
1749 * GDB now supports debugging microMIPS binaries.
1751 * The "info os" command on GNU/Linux can now display information on
1752 several new classes of objects managed by the operating system:
1753 "info os procgroups" lists process groups
1754 "info os files" lists file descriptors
1755 "info os sockets" lists internet-domain sockets
1756 "info os shm" lists shared-memory regions
1757 "info os semaphores" lists semaphores
1758 "info os msg" lists message queues
1759 "info os modules" lists loaded kernel modules
1761 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
1762 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
1763 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
1764 options and inspect the probe arguments using the new $_probe_arg family
1765 of convenience variables. You can obtain more information about SystemTap
1766 in <http://sourceware.org/systemtap/>.
1768 * GDB now supports reversible debugging on ARM, it allows you to
1769 debug basic ARM and THUMB instructions, and provides
1770 record/replay support.
1772 * The option "symbol-reloading" has been deleted as it is no longer used.
1776 ** GDB commands implemented in Python can now be put in command class
1779 ** The "maint set python print-stack on|off" is now deleted.
1781 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
1782 apply "flag enum"-style pretty-printing to any enum.
1784 ** gdb.lookup_symbol can now work when there is no current frame.
1786 ** gdb.Symbol now has a 'line' attribute, holding the line number in
1787 the source at which the symbol was defined.
1789 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
1790 method 'value'. The former indicates whether the symbol needs a
1791 frame in order to compute its value, and the latter computes the
1794 ** A new method 'referenced_value' on gdb.Value objects which can
1795 dereference pointer as well as C++ reference values.
1797 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
1798 which return the global and static blocks (as gdb.Block objects),
1799 of the underlying symbol table, respectively.
1801 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
1802 object associated with a PC value.
1804 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
1805 of the address range occupied by code for the current source line.
1807 * Go language support.
1808 GDB now supports debugging programs written in the Go programming
1811 * GDBserver now supports stdio connections.
1812 E.g. (gdb) target remote | ssh myhost gdbserver - hello
1814 * The binary "gdbtui" can no longer be built or installed.
1815 Use "gdb -tui" instead.
1817 * GDB will now print "flag" enums specially. A flag enum is one where
1818 all the enumerator values have no bits in common when pairwise
1819 "and"ed. When printing a value whose type is a flag enum, GDB will
1820 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
1821 (gdb) print (enum E) 3
1824 * The filename part of a linespec will now match trailing components
1825 of a source file name. For example, "break gcc/expr.c:1000" will
1826 now set a breakpoint in build/gcc/expr.c, but not
1827 build/libcpp/expr.c.
1829 * The "info proc" and "generate-core-file" commands will now also
1830 work on remote targets connected to GDBserver on Linux.
1832 * The command "info catch" has been removed. It has been disabled
1833 since December 2007.
1835 * The "catch exception" and "catch assert" commands now accept
1836 a condition at the end of the command, much like the "break"
1837 command does. For instance:
1839 (gdb) catch exception Constraint_Error if Barrier = True
1841 Previously, it was possible to add a condition to such catchpoints,
1842 but it had to be done as a second step, after the catchpoint had been
1843 created, using the "condition" command.
1845 * The "info static-tracepoint-marker" command will now also work on
1846 native Linux targets with in-process agent.
1848 * GDB can now set breakpoints on inlined functions.
1850 * The .gdb_index section has been updated to include symbols for
1851 inlined functions. GDB will ignore older .gdb_index sections by
1852 default, which could cause symbol files to be loaded more slowly
1853 until their .gdb_index sections can be recreated. The new command
1854 "set use-deprecated-index-sections on" will cause GDB to use any older
1855 .gdb_index sections it finds. This will restore performance, but the
1856 ability to set breakpoints on inlined functions will be lost in symbol
1857 files with older .gdb_index sections.
1859 The .gdb_index section has also been updated to record more information
1860 about each symbol. This speeds up the "info variables", "info functions"
1861 and "info types" commands when used with programs having the .gdb_index
1862 section, as well as speeding up debugging with shared libraries using
1863 the .gdb_index section.
1865 * Ada support for GDB/MI Variable Objects has been added.
1867 * GDB can now support 'breakpoint always-inserted mode' in 'record'
1872 ** New command -info-os is the MI equivalent of "info os".
1874 ** Output logs ("set logging" and related) now include MI output.
1878 ** "set use-deprecated-index-sections on|off"
1879 "show use-deprecated-index-sections on|off"
1880 Controls the use of deprecated .gdb_index sections.
1882 ** "catch load" and "catch unload" can be used to stop when a shared
1883 library is loaded or unloaded, respectively.
1885 ** "enable count" can be used to auto-disable a breakpoint after
1888 ** "info vtbl" can be used to show the virtual method tables for
1889 C++ and Java objects.
1891 ** "explore" and its sub commands "explore value" and "explore type"
1892 can be used to recursively explore values and types of
1893 expressions. These commands are available only if GDB is
1894 configured with '--with-python'.
1896 ** "info auto-load" shows status of all kinds of auto-loaded files,
1897 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
1898 sequences of commands files, "info auto-load python-scripts"
1899 shows status of auto-loading Python script files,
1900 "info auto-load local-gdbinit" shows status of loading init file
1901 (.gdbinit) from current directory and "info auto-load libthread-db" shows
1902 status of inferior specific thread debugging shared library loading.
1904 ** "info auto-load-scripts", "set auto-load-scripts on|off"
1905 and "show auto-load-scripts" commands have been deprecated, use their
1906 "info auto-load python-scripts", "set auto-load python-scripts on|off"
1907 and "show auto-load python-scripts" counterparts instead.
1909 ** "dprintf location,format,args..." creates a dynamic printf, which
1910 is basically a breakpoint that does a printf and immediately
1911 resumes your program's execution, so it is like a printf that you
1912 can insert dynamically at runtime instead of at compiletime.
1914 ** "set print symbol"
1916 Controls whether GDB attempts to display the symbol, if any,
1917 corresponding to addresses it prints. This defaults to "on", but
1918 you can set it to "off" to restore GDB's previous behavior.
1920 * Deprecated commands
1922 ** For the Renesas Super-H architecture, the "regs" command has been
1923 deprecated, and "info all-registers" should be used instead.
1927 Renesas RL78 rl78-*-elf
1928 HP OpenVMS ia64 ia64-hp-openvms*
1930 * GDBserver supports evaluation of breakpoint conditions. When
1931 support is advertised by GDBserver, GDB may be told to send the
1932 breakpoint conditions in bytecode form to GDBserver. GDBserver
1933 will only report the breakpoint trigger to GDB when its condition
1938 set mips compression
1939 show mips compression
1940 Select the compressed ISA encoding used in functions that have no symbol
1941 information available. The encoding can be set to either of:
1944 and is updated automatically from ELF file flags if available.
1946 set breakpoint condition-evaluation
1947 show breakpoint condition-evaluation
1948 Control whether breakpoint conditions are evaluated by GDB ("host") or by
1949 GDBserver ("target"). Default option "auto" chooses the most efficient
1951 This option can improve debugger efficiency depending on the speed of the
1955 Disable auto-loading globally.
1958 Show auto-loading setting of all kinds of auto-loaded files.
1960 set auto-load gdb-scripts on|off
1961 show auto-load gdb-scripts
1962 Control auto-loading of GDB canned sequences of commands files.
1964 set auto-load python-scripts on|off
1965 show auto-load python-scripts
1966 Control auto-loading of Python script files.
1968 set auto-load local-gdbinit on|off
1969 show auto-load local-gdbinit
1970 Control loading of init file (.gdbinit) from current directory.
1972 set auto-load libthread-db on|off
1973 show auto-load libthread-db
1974 Control auto-loading of inferior specific thread debugging shared library.
1976 set auto-load scripts-directory <dir1>[:<dir2>...]
1977 show auto-load scripts-directory
1978 Set a list of directories from which to load auto-loaded scripts.
1979 Automatically loaded Python scripts and GDB scripts are located in one
1980 of the directories listed by this option.
1981 The delimiter (':' above) may differ according to the host platform.
1983 set auto-load safe-path <dir1>[:<dir2>...]
1984 show auto-load safe-path
1985 Set a list of directories from which it is safe to auto-load files.
1986 The delimiter (':' above) may differ according to the host platform.
1988 set debug auto-load on|off
1989 show debug auto-load
1990 Control display of debugging info for auto-loading the files above.
1992 set dprintf-style gdb|call|agent
1994 Control the way in which a dynamic printf is performed; "gdb"
1995 requests a GDB printf command, while "call" causes dprintf to call a
1996 function in the inferior. "agent" requests that the target agent
1997 (such as GDBserver) do the printing.
1999 set dprintf-function <expr>
2000 show dprintf-function
2001 set dprintf-channel <expr>
2002 show dprintf-channel
2003 Set the function and optional first argument to the call when using
2004 the "call" style of dynamic printf.
2006 set disconnected-dprintf on|off
2007 show disconnected-dprintf
2008 Control whether agent-style dynamic printfs continue to be in effect
2009 after GDB disconnects.
2011 * New configure options
2013 --with-auto-load-dir
2014 Configure default value for the 'set auto-load scripts-directory'
2015 setting above. It defaults to '$debugdir:$datadir/auto-load',
2016 $debugdir representing global debugging info directories (available
2017 via 'show debug-file-directory') and $datadir representing GDB's data
2018 directory (available via 'show data-directory').
2020 --with-auto-load-safe-path
2021 Configure default value for the 'set auto-load safe-path' setting
2022 above. It defaults to the --with-auto-load-dir setting.
2024 --without-auto-load-safe-path
2025 Set 'set auto-load safe-path' to '/', effectively disabling this
2028 * New remote packets
2030 z0/z1 conditional breakpoints extension
2032 The z0/z1 breakpoint insertion packets have been extended to carry
2033 a list of conditional expressions over to the remote stub depending on the
2034 condition evaluation mode. The use of this extension can be controlled
2035 via the "set remote conditional-breakpoints-packet" command.
2039 Specify the signals which the remote stub may pass to the debugged
2040 program without GDB involvement.
2042 * New command line options
2044 --init-command=FILE, -ix Like --command, -x but execute it
2045 before loading inferior.
2046 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2047 execute it before loading inferior.
2049 *** Changes in GDB 7.4
2051 * GDB now handles ambiguous linespecs more consistently; the existing
2052 FILE:LINE support has been expanded to other types of linespecs. A
2053 breakpoint will now be set on all matching locations in all
2054 inferiors, and locations will be added or removed according to
2057 * GDB now allows you to skip uninteresting functions and files when
2058 stepping with the "skip function" and "skip file" commands.
2060 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2061 and "show remote hardware-watchpoint-length-limit". These allows to
2062 set or show the maximum length limit (in bytes) of a remote
2063 target hardware watchpoint.
2065 This allows e.g. to use "unlimited" hardware watchpoints with the
2066 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2067 watchpoints are slower than real hardware watchpoints but are
2068 significantly faster than gdb software watchpoints.
2072 ** The register_pretty_printer function in module gdb.printing now takes
2073 an optional `replace' argument. If True, the new printer replaces any
2076 ** The "maint set python print-stack on|off" command has been
2077 deprecated and will be deleted in GDB 7.5.
2078 A new command: "set python print-stack none|full|message" has
2079 replaced it. Additionally, the default for "print-stack" is
2080 now "message", which just prints the error message without
2083 ** A prompt substitution hook (prompt_hook) is now available to the
2086 ** A new Python module, gdb.prompt has been added to the GDB Python
2087 modules library. This module provides functionality for
2088 escape sequences in prompts (used by set/show
2089 extended-prompt). These escape sequences are replaced by their
2090 corresponding value.
2092 ** Python commands and convenience-functions located in
2093 'data-directory'/python/gdb/command and
2094 'data-directory'/python/gdb/function are now automatically loaded
2097 ** Blocks now provide four new attributes. global_block and
2098 static_block will return the global and static blocks
2099 respectively. is_static and is_global are boolean attributes
2100 that indicate if the block is one of those two types.
2102 ** Symbols now provide the "type" attribute, the type of the symbol.
2104 ** The "gdb.breakpoint" function has been deprecated in favor of
2107 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2108 of a function. This class is based on the "finish" command
2109 available in the CLI.
2111 ** Type objects for struct and union types now allow access to
2112 the fields using standard Python dictionary (mapping) methods.
2113 For example, "some_type['myfield']" now works, as does
2114 "some_type.items()".
2116 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2119 ** A new function, "deep_items" has been added to the gdb.types
2120 module in the GDB Python modules library. This function returns
2121 an iterator over the fields of a struct or union type. Unlike
2122 the standard Python "iteritems" method, it will recursively traverse
2123 any anonymous fields.
2127 ** "*stopped" events can report several new "reason"s, such as
2130 ** Breakpoint changes are now notified using new async records, like
2131 "=breakpoint-modified".
2133 ** New command -ada-task-info.
2135 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2136 $sdir specifies the default system locations of shared libraries.
2137 $pdir specifies the directory where the libpthread used by the application
2140 GDB no longer looks in $sdir and $pdir after it has searched the directories
2141 mentioned in libthread-db-search-path. If you want to search those
2142 directories, they must be specified in libthread-db-search-path.
2143 The default value of libthread-db-search-path on GNU/Linux and Solaris
2144 systems is now "$sdir:$pdir".
2146 $pdir is not supported by gdbserver, it is currently ignored.
2147 $sdir is supported by gdbserver.
2149 * New configure option --with-iconv-bin.
2150 When using the internationalization support like the one in the GNU C
2151 library, GDB will invoke the "iconv" program to get a list of supported
2152 character sets. If this program lives in a non-standard location, one can
2153 use this option to specify where to find it.
2155 * When natively debugging programs on PowerPC BookE processors running
2156 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2157 watchpoints, which specify a mask in addition to an address to watch.
2158 The mask specifies that some bits of an address (the bits which are
2159 reset in the mask) should be ignored when matching the address accessed
2160 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2161 section in the user manual for more details.
2163 * The new option --once causes GDBserver to stop listening for connections once
2164 the first connection is made. The listening port used by GDBserver will
2165 become available after that.
2167 * New commands "info macros" and "alias" have been added.
2169 * New function parameters suffix @entry specifies value of function parameter
2170 at the time the function got called. Entry values are available only since
2176 "!" is now an alias of the "shell" command.
2177 Note that no space is needed between "!" and SHELL COMMAND.
2181 watch EXPRESSION mask MASK_VALUE
2182 The watch command now supports the mask argument which allows creation
2183 of masked watchpoints, if the current architecture supports this feature.
2185 info auto-load-scripts [REGEXP]
2186 This command was formerly named "maintenance print section-scripts".
2187 It is now generally useful and is no longer a maintenance-only command.
2189 info macro [-all] [--] MACRO
2190 The info macro command has new options `-all' and `--'. The first for
2191 printing all definitions of a macro. The second for explicitly specifying
2192 the end of arguments and the beginning of the macro name in case the macro
2193 name starts with a hyphen.
2195 collect[/s] EXPRESSIONS
2196 The tracepoint collect command now takes an optional modifier "/s"
2197 that directs it to dereference pointer-to-character types and
2198 collect the bytes of memory up to a zero byte. The behavior is
2199 similar to what you see when you use the regular print command on a
2200 string. An optional integer following the "/s" sets a bound on the
2201 number of bytes that will be collected.
2204 The trace start command now interprets any supplied arguments as a
2205 note to be recorded with the trace run, with an effect similar to
2206 setting the variable trace-notes.
2209 The trace stop command now interprets any arguments as a note to be
2210 mentioned along with the tstatus report that the trace was stopped
2211 with a command. The effect is similar to setting the variable
2214 * Tracepoints can now be enabled and disabled at any time after a trace
2215 experiment has been started using the standard "enable" and "disable"
2216 commands. It is now possible to start a trace experiment with no enabled
2217 tracepoints; GDB will display a warning, but will allow the experiment to
2218 begin, assuming that tracepoints will be enabled as needed while the trace
2221 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2222 locations with 4-byte instructions, when they were previously
2223 limited to locations with instructions of 5 bytes or longer.
2227 set debug dwarf2-read
2228 show debug dwarf2-read
2229 Turns on or off display of debugging messages related to reading
2230 DWARF debug info. The default is off.
2232 set debug symtab-create
2233 show debug symtab-create
2234 Turns on or off display of debugging messages related to symbol table
2235 creation. The default is off.
2238 show extended-prompt
2239 Set the GDB prompt, and allow escape sequences to be inserted to
2240 display miscellaneous information (see 'help set extended-prompt'
2241 for the list of sequences). This prompt (and any information
2242 accessed through the escape sequences) is updated every time the
2243 prompt is displayed.
2245 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2246 show print entry-values
2247 Set printing of frame argument values at function entry. In some cases
2248 GDB can determine the value of function argument which was passed by the
2249 function caller, even if the value was modified inside the called function.
2251 set debug entry-values
2252 show debug entry-values
2253 Control display of debugging info for determining frame argument values at
2254 function entry and virtual tail call frames.
2256 set basenames-may-differ
2257 show basenames-may-differ
2258 Set whether a source file may have multiple base names.
2259 (A "base name" is the name of a file with the directory part removed.
2260 Example: The base name of "/home/user/hello.c" is "hello.c".)
2261 If set, GDB will canonicalize file names (e.g., expand symlinks)
2262 before comparing them. Canonicalization is an expensive operation,
2263 but it allows the same file be known by more than one base name.
2264 If not set (the default), all source files are assumed to have just
2265 one base name, and gdb will do file name comparisons more efficiently.
2271 Set a user name and notes for the current and any future trace runs.
2272 This is useful for long-running and/or disconnected traces, to
2273 inform others (or yourself) as to who is running the trace, supply
2274 contact information, or otherwise explain what is going on.
2276 set trace-stop-notes
2277 show trace-stop-notes
2278 Set a note attached to the trace run, that is displayed when the
2279 trace has been stopped by a tstop command. This is useful for
2280 instance as an explanation, if you are stopping a trace run that was
2281 started by someone else.
2283 * New remote packets
2287 Dynamically enable a tracepoint in a started trace experiment.
2291 Dynamically disable a tracepoint in a started trace experiment.
2295 Set the user and notes of the trace run.
2299 Query the current status of a tracepoint.
2303 Query the minimum length of instruction at which a fast tracepoint may
2306 * Dcache size (number of lines) and line-size are now runtime-configurable
2307 via "set dcache line" and "set dcache line-size" commands.
2311 Texas Instruments TMS320C6x tic6x-*-*
2315 Renesas RL78 rl78-*-elf
2317 *** Changes in GDB 7.3.1
2319 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2321 *** Changes in GDB 7.3
2323 * GDB has a new command: "thread find [REGEXP]".
2324 It finds the thread id whose name, target id, or thread extra info
2325 matches the given regular expression.
2327 * The "catch syscall" command now works on mips*-linux* targets.
2329 * The -data-disassemble MI command now supports modes 2 and 3 for
2330 dumping the instruction opcodes.
2332 * New command line options
2334 -data-directory DIR Specify DIR as the "data-directory".
2335 This is mostly for testing purposes.
2337 * The "maint set python auto-load on|off" command has been renamed to
2338 "set auto-load-scripts on|off".
2340 * GDB has a new command: "set directories".
2341 It is like the "dir" command except that it replaces the
2342 source path list instead of augmenting it.
2344 * GDB now understands thread names.
2346 On GNU/Linux, "info threads" will display the thread name as set by
2347 prctl or pthread_setname_np.
2349 There is also a new command, "thread name", which can be used to
2350 assign a name internally for GDB to display.
2353 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2354 has been integrated into GDB.
2358 ** The function gdb.Write now accepts an optional keyword 'stream'.
2359 This keyword, when provided, will direct the output to either
2360 stdout, stderr, or GDB's logging output.
2362 ** Parameters can now be be sub-classed in Python, and in particular
2363 you may implement the get_set_doc and get_show_doc functions.
2364 This improves how Parameter set/show documentation is processed
2365 and allows for more dynamic content.
2367 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2368 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2369 have an is_valid method.
2371 ** Breakpoints can now be sub-classed in Python, and in particular
2372 you may implement a 'stop' function that is executed each time
2373 the inferior reaches that breakpoint.
2375 ** New function gdb.lookup_global_symbol looks up a global symbol.
2377 ** GDB values in Python are now callable if the value represents a
2378 function. For example, if 'some_value' represents a function that
2379 takes two integer parameters and returns a value, you can call
2380 that function like so:
2382 result = some_value (10,20)
2384 ** Module gdb.types has been added.
2385 It contains a collection of utilities for working with gdb.Types objects:
2386 get_basic_type, has_field, make_enum_dict.
2388 ** Module gdb.printing has been added.
2389 It contains utilities for writing and registering pretty-printers.
2390 New classes: PrettyPrinter, SubPrettyPrinter,
2391 RegexpCollectionPrettyPrinter.
2392 New function: register_pretty_printer.
2394 ** New commands "info pretty-printers", "enable pretty-printer" and
2395 "disable pretty-printer" have been added.
2397 ** gdb.parameter("directories") is now available.
2399 ** New function gdb.newest_frame returns the newest frame in the
2402 ** The gdb.InferiorThread class has a new "name" attribute. This
2403 holds the thread's name.
2405 ** Python Support for Inferior events.
2406 Python scripts can add observers to be notified of events
2407 occurring in the process being debugged.
2408 The following events are currently supported:
2409 - gdb.events.cont Continue event.
2410 - gdb.events.exited Inferior exited event.
2411 - gdb.events.stop Signal received, and Breakpoint hit events.
2415 ** GDB now puts template parameters in scope when debugging in an
2416 instantiation. For example, if you have:
2418 template<int X> int func (void) { return X; }
2420 then if you step into func<5>, "print X" will show "5". This
2421 feature requires proper debuginfo support from the compiler; it
2422 was added to GCC 4.5.
2424 ** The motion commands "next", "finish", "until", and "advance" now
2425 work better when exceptions are thrown. In particular, GDB will
2426 no longer lose control of the inferior; instead, the GDB will
2427 stop the inferior at the point at which the exception is caught.
2428 This functionality requires a change in the exception handling
2429 code that was introduced in GCC 4.5.
2431 * GDB now follows GCC's rules on accessing volatile objects when
2432 reading or writing target state during expression evaluation.
2433 One notable difference to prior behavior is that "print x = 0"
2434 no longer generates a read of x; the value of the assignment is
2435 now always taken directly from the value being assigned.
2437 * GDB now has some support for using labels in the program's source in
2438 linespecs. For instance, you can use "advance label" to continue
2439 execution to a label.
2441 * GDB now has support for reading and writing a new .gdb_index
2442 section. This section holds a fast index of DWARF debugging
2443 information and can be used to greatly speed up GDB startup and
2444 operation. See the documentation for `save gdb-index' for details.
2446 * The "watch" command now accepts an optional "-location" argument.
2447 When used, this causes GDB to watch the memory referred to by the
2448 expression. Such a watchpoint is never deleted due to it going out
2451 * GDB now supports thread debugging of core dumps on GNU/Linux.
2453 GDB now activates thread debugging using the libthread_db library
2454 when debugging GNU/Linux core dumps, similarly to when debugging
2455 live processes. As a result, when debugging a core dump file, GDB
2456 is now able to display pthread_t ids of threads. For example, "info
2457 threads" shows the same output as when debugging the process when it
2458 was live. In earlier releases, you'd see something like this:
2461 * 1 LWP 6780 main () at main.c:10
2463 While now you see this:
2466 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2468 It is also now possible to inspect TLS variables when debugging core
2471 When debugging a core dump generated on a machine other than the one
2472 used to run GDB, you may need to point GDB at the correct
2473 libthread_db library with the "set libthread-db-search-path"
2474 command. See the user manual for more details on this command.
2476 * When natively debugging programs on PowerPC BookE processors running
2477 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2478 which stop execution of the inferior whenever it executes an instruction
2479 at any address within the specified range. See the "PowerPC Embedded"
2480 section in the user manual for more details.
2482 * New features in the GDB remote stub, GDBserver
2484 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2485 and i686 LynxOS (version 5.x).
2487 ** GDBserver is now supported on Blackfin Linux.
2489 * New native configurations
2491 ia64 HP-UX ia64-*-hpux*
2495 Analog Devices, Inc. Blackfin Processor bfin-*
2497 * Ada task switching is now supported on sparc-elf targets when
2498 debugging a program using the Ravenscar Profile. For more information,
2499 see the "Tasking Support when using the Ravenscar Profile" section
2500 in the GDB user manual.
2502 * Guile support was removed.
2504 * New features in the GNU simulator
2506 ** The --map-info flag lists all known core mappings.
2508 ** CFI flashes may be simulated via the "cfi" device.
2510 *** Changes in GDB 7.2
2512 * Shared library support for remote targets by default
2514 When GDB is configured for a generic, non-OS specific target, like
2515 for example, --target=arm-eabi or one of the many *-*-elf targets,
2516 GDB now queries remote stubs for loaded shared libraries using the
2517 `qXfer:libraries:read' packet. Previously, shared library support
2518 was always disabled for such configurations.
2522 ** Argument Dependent Lookup (ADL)
2524 In C++ ADL lookup directs function search to the namespaces of its
2525 arguments even if the namespace has not been imported.
2535 Here the compiler will search for `foo' in the namespace of 'b'
2536 and find A::foo. GDB now supports this. This construct is commonly
2537 used in the Standard Template Library for operators.
2539 ** Improved User Defined Operator Support
2541 In addition to member operators, GDB now supports lookup of operators
2542 defined in a namespace and imported with a `using' directive, operators
2543 defined in the global scope, operators imported implicitly from an
2544 anonymous namespace, and the ADL operators mentioned in the previous
2546 GDB now also supports proper overload resolution for all the previously
2547 mentioned flavors of operators.
2549 ** static const class members
2551 Printing of static const class members that are initialized in the
2552 class definition has been fixed.
2554 * Windows Thread Information Block access.
2556 On Windows targets, GDB now supports displaying the Windows Thread
2557 Information Block (TIB) structure. This structure is visible either
2558 by using the new command `info w32 thread-information-block' or, by
2559 dereferencing the new convenience variable named `$_tlb', a
2560 thread-specific pointer to the TIB. This feature is also supported
2561 when remote debugging using GDBserver.
2563 * Static tracepoints
2565 Static tracepoints are calls in the user program into a tracing
2566 library. One such library is a port of the LTTng kernel tracer to
2567 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
2568 When debugging with GDBserver, GDB now supports combining the GDB
2569 tracepoint machinery with such libraries. For example: the user can
2570 use GDB to probe a static tracepoint marker (a call from the user
2571 program into the tracing library) with the new "strace" command (see
2572 "New commands" below). This creates a "static tracepoint" in the
2573 breakpoint list, that can be manipulated with the same feature set
2574 as fast and regular tracepoints. E.g., collect registers, local and
2575 global variables, collect trace state variables, and define
2576 tracepoint conditions. In addition, the user can collect extra
2577 static tracepoint marker specific data, by collecting the new
2578 $_sdata internal variable. When analyzing the trace buffer, you can
2579 inspect $_sdata like any other variable available to GDB. For more
2580 information, see the "Tracepoints" chapter in GDB user manual. New
2581 remote packets have been defined to support static tracepoints, see
2582 the "New remote packets" section below.
2584 * Better reconstruction of tracepoints after disconnected tracing
2586 GDB will attempt to download the original source form of tracepoint
2587 definitions when starting a trace run, and then will upload these
2588 upon reconnection to the target, resulting in a more accurate
2589 reconstruction of the tracepoints that are in use on the target.
2593 You can now exercise direct control over the ways that GDB can
2594 affect your program. For instance, you can disallow the setting of
2595 breakpoints, so that the program can run continuously (assuming
2596 non-stop mode). In addition, the "observer" variable is available
2597 to switch all of the different controls; in observer mode, GDB
2598 cannot affect the target's behavior at all, which is useful for
2599 tasks like diagnosing live systems in the field.
2601 * The new convenience variable $_thread holds the number of the
2604 * New remote packets
2608 Return the address of the Windows Thread Information Block of a given thread.
2612 In response to several of the tracepoint packets, the target may now
2613 also respond with a number of intermediate `qRelocInsn' request
2614 packets before the final result packet, to have GDB handle
2615 relocating an instruction to execute at a different address. This
2616 is particularly useful for stubs that support fast tracepoints. GDB
2617 reports support for this feature in the qSupported packet.
2621 List static tracepoint markers in the target program.
2625 List static tracepoint markers at a given address in the target
2628 qXfer:statictrace:read
2630 Read the static trace data collected (by a `collect $_sdata'
2631 tracepoint action). The remote stub reports support for this packet
2632 to gdb's qSupported query.
2636 Send the current settings of GDB's permission flags.
2640 Send part of the source (textual) form of a tracepoint definition,
2641 which includes location, conditional, and action list.
2643 * The source command now accepts a -s option to force searching for the
2644 script in the source search path even if the script name specifies
2647 * New features in the GDB remote stub, GDBserver
2649 - GDBserver now support tracepoints (including fast tracepoints, and
2650 static tracepoints). The feature is currently supported by the
2651 i386-linux and amd64-linux builds. See the "Tracepoints support
2652 in gdbserver" section in the manual for more information.
2654 GDBserver JIT compiles the tracepoint's conditional agent
2655 expression bytecode into native code whenever possible for low
2656 overhead dynamic tracepoints conditionals. For such tracepoints,
2657 an expression that examines program state is evaluated when the
2658 tracepoint is reached, in order to determine whether to capture
2659 trace data. If the condition is simple and false, processing the
2660 tracepoint finishes very quickly and no data is gathered.
2662 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
2663 for static tracepoints support.
2665 - GDBserver now supports x86_64 Windows 64-bit debugging.
2667 * GDB now sends xmlRegisters= in qSupported packet to indicate that
2668 it understands register description.
2670 * The --batch flag now disables pagination and queries.
2672 * X86 general purpose registers
2674 GDB now supports reading/writing byte, word and double-word x86
2675 general purpose registers directly. This means you can use, say,
2676 $ah or $ax to refer, respectively, to the byte register AH and
2677 16-bit word register AX that are actually portions of the 32-bit
2678 register EAX or 64-bit register RAX.
2680 * The `commands' command now accepts a range of breakpoints to modify.
2681 A plain `commands' following a command that creates multiple
2682 breakpoints affects all the breakpoints set by that command. This
2683 applies to breakpoints set by `rbreak', and also applies when a
2684 single `break' command creates multiple breakpoints (e.g.,
2685 breakpoints on overloaded c++ functions).
2687 * The `rbreak' command now accepts a filename specification as part of
2688 its argument, limiting the functions selected by the regex to those
2689 in the specified file.
2691 * Support for remote debugging Windows and SymbianOS shared libraries
2692 from Unix hosts has been improved. Non Windows GDB builds now can
2693 understand target reported file names that follow MS-DOS based file
2694 system semantics, such as file names that include drive letters and
2695 use the backslash character as directory separator. This makes it
2696 possible to transparently use the "set sysroot" and "set
2697 solib-search-path" on Unix hosts to point as host copies of the
2698 target's shared libraries. See the new command "set
2699 target-file-system-kind" described below, and the "Commands to
2700 specify files" section in the user manual for more information.
2704 eval template, expressions...
2705 Convert the values of one or more expressions under the control
2706 of the string template to a command line, and call it.
2708 set target-file-system-kind unix|dos-based|auto
2709 show target-file-system-kind
2710 Set or show the assumed file system kind for target reported file
2713 save breakpoints <filename>
2714 Save all current breakpoint definitions to a file suitable for use
2715 in a later debugging session. To read the saved breakpoint
2716 definitions, use the `source' command.
2718 `save tracepoints' is a new alias for `save-tracepoints'. The latter
2721 info static-tracepoint-markers
2722 Display information about static tracepoint markers in the target.
2724 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
2725 Define a static tracepoint by probing a marker at the given
2726 function, line, address, or marker ID.
2730 Enable and disable observer mode.
2732 set may-write-registers on|off
2733 set may-write-memory on|off
2734 set may-insert-breakpoints on|off
2735 set may-insert-tracepoints on|off
2736 set may-insert-fast-tracepoints on|off
2737 set may-interrupt on|off
2738 Set individual permissions for GDB effects on the target. Note that
2739 some of these settings can have undesirable or surprising
2740 consequences, particularly when changed in the middle of a session.
2741 For instance, disabling the writing of memory can prevent
2742 breakpoints from being inserted, cause single-stepping to fail, or
2743 even crash your program, if you disable after breakpoints have been
2744 inserted. However, GDB should not crash.
2746 set record memory-query on|off
2747 show record memory-query
2748 Control whether to stop the inferior if memory changes caused
2749 by an instruction cannot be recorded.
2754 The disassemble command now supports "start,+length" form of two arguments.
2758 ** GDB now provides a new directory location, called the python directory,
2759 where Python scripts written for GDB can be installed. The location
2760 of that directory is <data-directory>/python, where <data-directory>
2761 is the GDB data directory. For more details, see section `Scripting
2762 GDB using Python' in the manual.
2764 ** The GDB Python API now has access to breakpoints, symbols, symbol
2765 tables, program spaces, inferiors, threads and frame's code blocks.
2766 Additionally, GDB Parameters can now be created from the API, and
2767 manipulated via set/show in the CLI.
2769 ** New functions gdb.target_charset, gdb.target_wide_charset,
2770 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
2772 ** New exception gdb.GdbError.
2774 ** Pretty-printers are now also looked up in the current program space.
2776 ** Pretty-printers can now be individually enabled and disabled.
2778 ** GDB now looks for names of Python scripts to auto-load in a
2779 special section named `.debug_gdb_scripts', in addition to looking
2780 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
2782 * Tracepoint actions were unified with breakpoint commands. In particular,
2783 there are no longer differences in "info break" output for breakpoints and
2784 tracepoints and the "commands" command can be used for both tracepoints and
2785 regular breakpoints.
2789 ARM Symbian arm*-*-symbianelf*
2791 * D language support.
2792 GDB now supports debugging programs written in the D programming
2795 * GDB now supports the extended ptrace interface for PowerPC which is
2796 available since Linux kernel version 2.6.34. This automatically enables
2797 any hardware breakpoints and additional hardware watchpoints available in
2798 the processor. The old ptrace interface exposes just one hardware
2799 watchpoint and no hardware breakpoints.
2801 * GDB is now able to use the Data Value Compare (DVC) register available on
2802 embedded PowerPC processors to implement in hardware simple watchpoint
2803 conditions of the form:
2805 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
2807 This works in native GDB running on Linux kernels with the extended ptrace
2808 interface mentioned above.
2810 *** Changes in GDB 7.1
2814 ** Namespace Support
2816 GDB now supports importing of namespaces in C++. This enables the
2817 user to inspect variables from imported namespaces. Support for
2818 namepace aliasing has also been added. So, if a namespace is
2819 aliased in the current scope (e.g. namepace C=A; ) the user can
2820 print variables using the alias (e.g. (gdb) print C::x).
2824 All known bugs relating to the printing of virtual base class were
2825 fixed. It is now possible to call overloaded static methods using a
2830 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
2831 and reinterpret_cast<> are now handled by the C++ expression parser.
2835 Xilinx MicroBlaze microblaze-*-*
2840 Xilinx MicroBlaze microblaze
2843 * Multi-program debugging.
2845 GDB now has support for multi-program (a.k.a. multi-executable or
2846 multi-exec) debugging. This allows for debugging multiple inferiors
2847 simultaneously each running a different program under the same GDB
2848 session. See "Debugging Multiple Inferiors and Programs" in the
2849 manual for more information. This implied some user visible changes
2850 in the multi-inferior support. For example, "info inferiors" now
2851 lists inferiors that are not running yet or that have exited
2852 already. See also "New commands" and "New options" below.
2854 * New tracing features
2856 GDB's tracepoint facility now includes several new features:
2858 ** Trace state variables
2860 GDB tracepoints now include support for trace state variables, which
2861 are variables managed by the target agent during a tracing
2862 experiment. They are useful for tracepoints that trigger each
2863 other, so for instance one tracepoint can count hits in a variable,
2864 and then a second tracepoint has a condition that is true when the
2865 count reaches a particular value. Trace state variables share the
2866 $-syntax of GDB convenience variables, and can appear in both
2867 tracepoint actions and condition expressions. Use the "tvariable"
2868 command to create, and "info tvariables" to view; see "Trace State
2869 Variables" in the manual for more detail.
2873 GDB now includes an option for defining fast tracepoints, which
2874 targets may implement more efficiently, such as by installing a jump
2875 into the target agent rather than a trap instruction. The resulting
2876 speedup can be by two orders of magnitude or more, although the
2877 tradeoff is that some program locations on some target architectures
2878 might not allow fast tracepoint installation, for instance if the
2879 instruction to be replaced is shorter than the jump. To request a
2880 fast tracepoint, use the "ftrace" command, with syntax identical to
2881 the regular trace command.
2883 ** Disconnected tracing
2885 It is now possible to detach GDB from the target while it is running
2886 a trace experiment, then reconnect later to see how the experiment
2887 is going. In addition, a new variable disconnected-tracing lets you
2888 tell the target agent whether to continue running a trace if the
2889 connection is lost unexpectedly.
2893 GDB now has the ability to save the trace buffer into a file, and
2894 then use that file as a target, similarly to you can do with
2895 corefiles. You can select trace frames, print data that was
2896 collected in them, and use tstatus to display the state of the
2897 tracing run at the moment that it was saved. To create a trace
2898 file, use "tsave <filename>", and to use it, do "target tfile
2901 ** Circular trace buffer
2903 You can ask the target agent to handle the trace buffer as a
2904 circular buffer, discarding the oldest trace frames to make room for
2905 newer ones, by setting circular-trace-buffer to on. This feature may
2906 not be available for all target agents.
2911 The disassemble command, when invoked with two arguments, now requires
2912 the arguments to be comma-separated.
2915 The info variables command now displays variable definitions. Files
2916 which only declare a variable are not shown.
2919 The source command is now capable of sourcing Python scripts.
2920 This feature is dependent on the debugger being build with Python
2923 Related to this enhancement is also the introduction of a new command
2924 "set script-extension" (see below).
2926 * New commands (for set/show, see "New options" below)
2928 record save [<FILENAME>]
2929 Save a file (in core file format) containing the process record
2930 execution log for replay debugging at a later time.
2932 record restore <FILENAME>
2933 Restore the process record execution log that was saved at an
2934 earlier time, for replay debugging.
2936 add-inferior [-copies <N>] [-exec <FILENAME>]
2939 clone-inferior [-copies <N>] [ID]
2940 Make a new inferior ready to execute the same program another
2941 inferior has loaded.
2946 maint info program-spaces
2947 List the program spaces loaded into GDB.
2949 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
2950 show remote interrupt-sequence
2951 Allow the user to select one of ^C, a BREAK signal or BREAK-g
2952 as the sequence to the remote target in order to interrupt the execution.
2953 Ctrl-C is a default. Some system prefers BREAK which is high level of
2954 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
2955 Magic SysRq g. It is BREAK signal and character 'g'.
2957 set remote interrupt-on-connect [on | off]
2958 show remote interrupt-on-connect
2959 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
2960 remote target when gdb connects to it. This is needed when you debug
2963 set remotebreak [on | off]
2965 Deprecated. Use "set/show remote interrupt-sequence" instead.
2967 tvariable $NAME [ = EXP ]
2968 Create or modify a trace state variable.
2971 List trace state variables and their values.
2973 delete tvariable $NAME ...
2974 Delete one or more trace state variables.
2977 Evaluate the given expressions without collecting anything into the
2978 trace buffer. (Valid in tracepoint actions only.)
2980 ftrace FN / FILE:LINE / *ADDR
2981 Define a fast tracepoint at the given function, line, or address.
2983 * New expression syntax
2985 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
2986 GDB now parses 0b101010 identically with 42.
2990 set follow-exec-mode new|same
2991 show follow-exec-mode
2992 Control whether GDB reuses the same inferior across an exec call or
2993 creates a new one. This is useful to be able to restart the old
2994 executable after the inferior having done an exec call.
2996 set default-collect EXPR, ...
2997 show default-collect
2998 Define a list of expressions to be collected at each tracepoint.
2999 This is a useful way to ensure essential items are not overlooked,
3000 such as registers or a critical global variable.
3002 set disconnected-tracing
3003 show disconnected-tracing
3004 If set to 1, the target is instructed to continue tracing if it
3005 loses its connection to GDB. If 0, the target is to stop tracing
3008 set circular-trace-buffer
3009 show circular-trace-buffer
3010 If set to on, the target is instructed to use a circular trace buffer
3011 and discard the oldest trace frames instead of stopping the trace due
3012 to a full trace buffer. If set to off, the trace stops when the buffer
3013 fills up. Some targets may not support this.
3015 set script-extension off|soft|strict
3016 show script-extension
3017 If set to "off", the debugger does not perform any script language
3018 recognition, and all sourced files are assumed to be GDB scripts.
3019 If set to "soft" (the default), files are sourced according to
3020 filename extension, falling back to GDB scripts if the first
3022 If set to "strict", files are sourced according to filename extension.
3024 set ada trust-PAD-over-XVS on|off
3025 show ada trust-PAD-over-XVS
3026 If off, activate a workaround against a bug in the debugging information
3027 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3028 the GCC sources for more information about the GNAT encoding and
3029 PAD types in particular). It is always safe to set this option to
3030 off, but this introduces a slight performance penalty. The default
3033 * Python API Improvements
3035 ** GDB provides the new class gdb.LazyString. This is useful in
3036 some pretty-printing cases. The new method gdb.Value.lazy_string
3037 provides a simple way to create objects of this type.
3039 ** The fields returned by gdb.Type.fields now have an
3040 `is_base_class' attribute.
3042 ** The new method gdb.Type.range returns the range of an array type.
3044 ** The new method gdb.parse_and_eval can be used to parse and
3045 evaluate an expression.
3047 * New remote packets
3050 Define a trace state variable.
3053 Get the current value of a trace state variable.
3056 Set desired tracing behavior upon disconnection.
3059 Set the trace buffer to be linear or circular.
3062 Get data about the tracepoints currently in use.
3066 Process record now works correctly with hardware watchpoints.
3068 Multiple bug fixes have been made to the mips-irix port, making it
3069 much more reliable. In particular:
3070 - Debugging threaded applications is now possible again. Previously,
3071 GDB would hang while starting the program, or while waiting for
3072 the program to stop at a breakpoint.
3073 - Attaching to a running process no longer hangs.
3074 - An error occurring while loading a core file has been fixed.
3075 - Changing the value of the PC register now works again. This fixes
3076 problems observed when using the "jump" command, or when calling
3077 a function from GDB, or even when assigning a new value to $pc.
3078 - With the "finish" and "return" commands, the return value for functions
3079 returning a small array is now correctly printed.
3080 - It is now possible to break on shared library code which gets executed
3081 during a shared library init phase (code executed while executing
3082 their .init section). Previously, the breakpoint would have no effect.
3083 - GDB is now able to backtrace through the signal handler for
3084 non-threaded programs.
3086 PIE (Position Independent Executable) programs debugging is now supported.
3087 This includes debugging execution of PIC (Position Independent Code) shared
3088 libraries although for that, it should be possible to run such libraries as an
3091 *** Changes in GDB 7.0
3093 * GDB now has an interface for JIT compilation. Applications that
3094 dynamically generate code can create symbol files in memory and register
3095 them with GDB. For users, the feature should work transparently, and
3096 for JIT developers, the interface is documented in the GDB manual in the
3097 "JIT Compilation Interface" chapter.
3099 * Tracepoints may now be conditional. The syntax is as for
3100 breakpoints; either an "if" clause appended to the "trace" command,
3101 or the "condition" command is available. GDB sends the condition to
3102 the target for evaluation using the same bytecode format as is used
3103 for tracepoint actions.
3105 * The disassemble command now supports: an optional /r modifier, print the
3106 raw instructions in hex as well as in symbolic form, and an optional /m
3107 modifier to print mixed source+assembly.
3109 * Process record and replay
3111 In a architecture environment that supports ``process record and
3112 replay'', ``process record and replay'' target can record a log of
3113 the process execution, and replay it with both forward and reverse
3116 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3117 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3118 set execution-direction {forward|reverse}, for targets that support
3121 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3122 feature is available with a native GDB running on kernel version
3125 * GDB now has support for multi-byte and wide character sets on the
3126 target. Strings whose character type is wchar_t, char16_t, or
3127 char32_t are now correctly printed. GDB supports wide- and unicode-
3128 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3129 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3130 `printf'. This feature requires iconv to work properly; if your
3131 system does not have a working iconv, GDB can use GNU libiconv. See
3132 the installation instructions for more information.
3134 * GDB now supports automatic retrieval of shared library files from
3135 remote targets. To use this feature, specify a system root that begins
3136 with the `remote:' prefix, either via the `set sysroot' command or via
3137 the `--with-sysroot' configure-time option.
3139 * "info sharedlibrary" now takes an optional regex of libraries to show,
3140 and it now reports if a shared library has no debugging information.
3142 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3143 now complete on file names.
3145 * When completing in expressions, gdb will attempt to limit
3146 completions to allowable structure or union fields, where appropriate.
3147 For instance, consider:
3149 # struct example { int f1; double f2; };
3150 # struct example variable;
3153 If the user types TAB at the end of this command line, the available
3154 completions will be "f1" and "f2".
3156 * Inlined functions are now supported. They show up in backtraces, and
3157 the "step", "next", and "finish" commands handle them automatically.
3159 * GDB now supports the token-splicing (##) and stringification (#)
3160 operators when expanding macros. It also supports variable-arity
3163 * GDB now supports inspecting extra signal information, exported by
3164 the new $_siginfo convenience variable. The feature is currently
3165 implemented on linux ARM, i386 and amd64.
3167 * GDB can now display the VFP floating point registers and NEON vector
3168 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3169 can provide these registers (requires Linux 2.6.30 or later). Remote
3170 and simulator targets may also provide them.
3172 * New remote packets
3175 Search memory for a sequence of bytes.
3178 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3179 operation over reliable transport links. Use of this packet is
3180 controlled by the `set remote noack-packet' command.
3183 Kill the process with the specified process ID. Use this in preference
3184 to `k' when multiprocess protocol extensions are supported.
3187 Obtains additional operating system information
3191 Read or write additional signal information.
3193 * Removed remote protocol undocumented extension
3195 An undocumented extension to the remote protocol's `S' stop reply
3196 packet that permited the stub to pass a process id was removed.
3197 Remote servers should use the `T' stop reply packet instead.
3199 * GDB now supports multiple function calling conventions according to the
3200 DWARF-2 DW_AT_calling_convention function attribute.
3202 * The SH target utilizes the aforementioned change to distinguish between gcc
3203 and Renesas calling convention. It also adds the new CLI commands
3204 `set/show sh calling-convention'.
3206 * GDB can now read compressed debug sections, as produced by GNU gold
3207 with the --compress-debug-sections=zlib flag.
3209 * 64-bit core files are now supported on AIX.
3211 * Thread switching is now supported on Tru64.
3213 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3214 which will be allocated using malloc later in program execution.
3216 * The qXfer:libraries:read remote procotol packet now allows passing a
3217 list of section offsets.
3219 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3220 conditions handling signals delivered during attach or thread creation
3221 have also been fixed.
3223 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3224 From the user's standpoint, all unqualified instances of True and False
3225 are treated as the standard definitions, regardless of context.
3227 * GDB now parses C++ symbol and type names more flexibly. For
3230 template<typename T> class C { };
3233 GDB will now correctly handle all of:
3235 ptype C<char const *>
3236 ptype C<char const*>
3237 ptype C<const char *>
3238 ptype C<const char*>
3240 * New features in the GDB remote stub, gdbserver
3242 - The "--wrapper" command-line argument tells gdbserver to use a
3243 wrapper program to launch programs for debugging.
3245 - On PowerPC and S/390 targets, it is now possible to use a single
3246 gdbserver executable to debug both 32-bit and 64-bit programs.
3247 (This requires gdbserver itself to be built as a 64-bit executable.)
3249 - gdbserver uses the new noack protocol mode for TCP connections to
3250 reduce communications latency, if also supported and enabled in GDB.
3252 - Support for the sparc64-linux-gnu target is now included in
3255 - The amd64-linux build of gdbserver now supports debugging both
3256 32-bit and 64-bit programs.
3258 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3259 now support hardware watchpoints, and will use them automatically
3264 GDB now has support for scripting using Python. Whether this is
3265 available is determined at configure time.
3267 New GDB commands can now be written in Python.
3269 * Ada tasking support
3271 Ada tasks can now be inspected in GDB. The following commands have
3275 Print the list of Ada tasks.
3277 Print detailed information about task number N.
3279 Print the task number of the current task.
3281 Switch the context of debugging to task number N.
3283 * Support for user-defined prefixed commands. The "define" command can
3284 add new commands to existing prefixes, e.g. "target".
3286 * Multi-inferior, multi-process debugging.
3288 GDB now has generalized support for multi-inferior debugging. See
3289 "Debugging Multiple Inferiors" in the manual for more information.
3290 Although availability still depends on target support, the command
3291 set is more uniform now. The GNU/Linux specific multi-forks support
3292 has been migrated to this new framework. This implied some user
3293 visible changes; see "New commands" and also "Removed commands"
3296 * Target descriptions can now describe the target OS ABI. See the
3297 "Target Description Format" section in the user manual for more
3300 * Target descriptions can now describe "compatible" architectures
3301 to indicate that the target can execute applications for a different
3302 architecture in addition to those for the main target architecture.
3303 See the "Target Description Format" section in the user manual for
3306 * Multi-architecture debugging.
3308 GDB now includes general supports for debugging applications on
3309 hybrid systems that use more than one single processor architecture
3310 at the same time. Each such hybrid architecture still requires
3311 specific support to be added. The only hybrid architecture supported
3312 in this version of GDB is the Cell Broadband Engine.
3314 * GDB now supports integrated debugging of Cell/B.E. applications that
3315 use both the PPU and SPU architectures. To enable support for hybrid
3316 Cell/B.E. debugging, you need to configure GDB to support both the
3317 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3318 --enable-targets configure option.
3320 * Non-stop mode debugging.
3322 For some targets, GDB now supports an optional mode of operation in
3323 which you can examine stopped threads while other threads continue
3324 to execute freely. This is referred to as non-stop mode, with the
3325 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3326 section in the user manual for more information.
3328 To be able to support remote non-stop debugging, a remote stub needs
3329 to implement the non-stop mode remote protocol extensions, as
3330 described in the "Remote Non-Stop" section of the user manual. The
3331 GDB remote stub, gdbserver, has been adjusted to support these
3332 extensions on linux targets.
3334 * New commands (for set/show, see "New options" below)
3336 catch syscall [NAME(S) | NUMBER(S)]
3337 Catch system calls. Arguments, which should be names of system
3338 calls or their numbers, mean catch only those syscalls. Without
3339 arguments, every syscall will be caught. When the inferior issues
3340 any of the specified syscalls, GDB will stop and announce the system
3341 call, both when it is called and when its call returns. This
3342 feature is currently available with a native GDB running on the
3343 Linux Kernel, under the following architectures: x86, x86_64,
3344 PowerPC and PowerPC64.
3346 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3348 Search memory for a sequence of bytes.
3350 maint set python print-stack
3351 maint show python print-stack
3352 Show a stack trace when an error is encountered in a Python script.
3355 Invoke CODE by passing it to the Python interpreter.
3360 These allow macros to be defined, undefined, and listed
3364 Show operating system information about processes.
3367 List the inferiors currently under GDB's control.
3370 Switch focus to inferior number NUM.
3373 Detach from inferior number NUM.
3376 Kill inferior number NUM.
3380 set spu stop-on-load
3381 show spu stop-on-load
3382 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3384 set spu auto-flush-cache
3385 show spu auto-flush-cache
3386 Control whether to automatically flush the software-managed cache
3387 during Cell/B.E. debugging.
3389 set sh calling-convention
3390 show sh calling-convention
3391 Control the calling convention used when calling SH target functions.
3394 show debug timestamp
3395 Control display of timestamps with GDB debugging output.
3397 set disassemble-next-line
3398 show disassemble-next-line
3399 Control display of disassembled source lines or instructions when
3402 set remote noack-packet
3403 show remote noack-packet
3404 Set/show the use of remote protocol QStartNoAckMode packet. See above
3405 under "New remote packets."
3407 set remote query-attached-packet
3408 show remote query-attached-packet
3409 Control use of remote protocol `qAttached' (query-attached) packet.
3411 set remote read-siginfo-object
3412 show remote read-siginfo-object
3413 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3416 set remote write-siginfo-object
3417 show remote write-siginfo-object
3418 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3421 set remote reverse-continue
3422 show remote reverse-continue
3423 Control use of remote protocol 'bc' (reverse-continue) packet.
3425 set remote reverse-step
3426 show remote reverse-step
3427 Control use of remote protocol 'bs' (reverse-step) packet.
3429 set displaced-stepping
3430 show displaced-stepping
3431 Control displaced stepping mode. Displaced stepping is a way to
3432 single-step over breakpoints without removing them from the debuggee.
3433 Also known as "out-of-line single-stepping".
3436 show debug displaced
3437 Control display of debugging info for displaced stepping.
3439 maint set internal-error
3440 maint show internal-error
3441 Control what GDB does when an internal error is detected.
3443 maint set internal-warning
3444 maint show internal-warning
3445 Control what GDB does when an internal warning is detected.
3450 Use a wrapper program to launch programs for debugging.
3452 set multiple-symbols (all|ask|cancel)
3453 show multiple-symbols
3454 The value of this variable can be changed to adjust the debugger behavior
3455 when an expression or a breakpoint location contains an ambiguous symbol
3456 name (an overloaded function name, for instance).
3458 set breakpoint always-inserted
3459 show breakpoint always-inserted
3460 Keep breakpoints always inserted in the target, as opposed to inserting
3461 them when resuming the target, and removing them when the target stops.
3462 This option can improve debugger performance on slow remote targets.
3464 set arm fallback-mode (arm|thumb|auto)
3465 show arm fallback-mode
3466 set arm force-mode (arm|thumb|auto)
3468 These commands control how ARM GDB determines whether instructions
3469 are ARM or Thumb. The default for both settings is auto, which uses
3470 the current CPSR value for instructions without symbols; previous
3471 versions of GDB behaved as if "set arm fallback-mode arm".
3473 set disable-randomization
3474 show disable-randomization
3475 Standalone programs run with the virtual address space randomization enabled
3476 by default on some platforms. This option keeps the addresses stable across
3477 multiple debugging sessions.
3481 Control whether other threads are stopped or not when some thread hits
3486 Requests that asynchronous execution is enabled in the target, if available.
3487 In this case, it's possible to resume target in the background, and interact
3488 with GDB while the target is running. "show target-async" displays the
3489 current state of asynchronous execution of the target.
3491 set target-wide-charset
3492 show target-wide-charset
3493 The target-wide-charset is the name of the character set that GDB
3494 uses when printing characters whose type is wchar_t.
3496 set tcp auto-retry (on|off)
3498 set tcp connect-timeout
3499 show tcp connect-timeout
3500 These commands allow GDB to retry failed TCP connections to a remote stub
3501 with a specified timeout period; this is useful if the stub is launched
3502 in parallel with GDB but may not be ready to accept connections immediately.
3504 set libthread-db-search-path
3505 show libthread-db-search-path
3506 Control list of directories which GDB will search for appropriate
3509 set schedule-multiple (on|off)
3510 show schedule-multiple
3511 Allow GDB to resume all threads of all processes or only threads of
3512 the current process.
3516 Use more aggressive caching for accesses to the stack. This improves
3517 performance of remote debugging (particularly backtraces) without
3518 affecting correctness.
3520 set interactive-mode (on|off|auto)
3521 show interactive-mode
3522 Control whether GDB runs in interactive mode (on) or not (off).
3523 When in interactive mode, GDB waits for the user to answer all
3524 queries. Otherwise, GDB does not wait and assumes the default
3525 answer. When set to auto (the default), GDB determines which
3526 mode to use based on the stdin settings.
3531 For program forks, this is replaced by the new more generic `info
3532 inferiors' command. To list checkpoints, you can still use the
3533 `info checkpoints' command, which was an alias for the `info forks'
3537 Replaced by the new `inferior' command. To switch between
3538 checkpoints, you can still use the `restart' command, which was an
3539 alias for the `fork' command.
3542 This is removed, since some targets don't have a notion of
3543 processes. To switch between processes, you can still use the
3544 `inferior' command using GDB's own inferior number.
3547 For program forks, this is replaced by the new more generic `kill
3548 inferior' command. To delete a checkpoint, you can still use the
3549 `delete checkpoint' command, which was an alias for the `delete
3553 For program forks, this is replaced by the new more generic `detach
3554 inferior' command. To detach a checkpoint, you can still use the
3555 `detach checkpoint' command, which was an alias for the `detach
3558 * New native configurations
3560 x86/x86_64 Darwin i[34567]86-*-darwin*
3562 x86_64 MinGW x86_64-*-mingw*
3566 Lattice Mico32 lm32-*
3567 x86 DICOS i[34567]86-*-dicos*
3568 x86_64 DICOS x86_64-*-dicos*
3571 * The GDB remote stub, gdbserver, now supports x86 Windows CE
3572 (mingw32ce) debugging.
3578 These commands were actually not implemented on any target.
3580 *** Changes in GDB 6.8
3582 * New native configurations
3584 NetBSD/hppa hppa*-*netbsd*
3585 Xtensa GNU/Linux xtensa*-*-linux*
3589 NetBSD/hppa hppa*-*-netbsd*
3590 Xtensa GNU/Lunux xtensa*-*-linux*
3592 * Change in command line behavior -- corefiles vs. process ids.
3594 When the '-p NUMBER' or '--pid NUMBER' options are used, and
3595 attaching to process NUMBER fails, GDB no longer attempts to open a
3596 core file named NUMBER. Attaching to a program using the -c option
3597 is no longer supported. Instead, use the '-p' or '--pid' options.
3599 * GDB can now be built as a native debugger for debugging Windows x86
3600 (mingw32) Portable Executable (PE) programs.
3602 * Pending breakpoints no longer change their number when their address
3605 * GDB now supports breakpoints with multiple locations,
3606 including breakpoints on C++ constructors, inside C++ templates,
3607 and in inlined functions.
3609 * GDB's ability to debug optimized code has been improved. GDB more
3610 accurately identifies function bodies and lexical blocks that occupy
3611 more than one contiguous range of addresses.
3613 * Target descriptions can now describe registers for PowerPC.
3615 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
3616 registers on PowerPC targets.
3618 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
3619 targets even when the libthread_db library is not available.
3621 * The GDB remote stub, gdbserver, now supports the new file transfer
3622 commands (remote put, remote get, and remote delete).
3624 * The GDB remote stub, gdbserver, now supports run and attach in
3625 extended-remote mode.
3627 * hppa*64*-*-hpux11* target broken
3628 The debugger is unable to start a program and fails with the following
3629 error: "Error trying to get information about dynamic linker".
3630 The gdb-6.7 release is also affected.
3632 * GDB now supports the --enable-targets= configure option to allow
3633 building a single GDB executable that supports multiple remote
3634 target architectures.
3636 * GDB now supports debugging C and C++ programs which use the
3637 Decimal Floating Point extension. In addition, the PowerPC target
3638 now has a set of pseudo-registers to inspect decimal float values
3639 stored in two consecutive float registers.
3641 * The -break-insert MI command can optionally create pending
3644 * Improved support for debugging Ada
3645 Many improvements to the Ada language support have been made. These
3647 - Better support for Ada2005 interface types
3648 - Improved handling of arrays and slices in general
3649 - Better support for Taft-amendment types
3650 - The '{type} ADDRESS' expression is now allowed on the left hand-side
3652 - Improved command completion in Ada
3655 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
3660 set print frame-arguments (all|scalars|none)
3661 show print frame-arguments
3662 The value of this variable can be changed to control which argument
3663 values should be printed by the debugger when displaying a frame.
3668 Transfer files to and from a remote target, and delete remote files.
3675 Transfer files to and from a remote target, and delete remote files.
3677 * New remote packets
3684 Open, close, read, write, and delete files on the remote system.
3687 Attach to an existing process on the remote system, in extended-remote
3691 Run a new process on the remote system, in extended-remote mode.
3693 *** Changes in GDB 6.7
3695 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
3696 bfd, libiberty and opcodes, as revealed by static analysis donated by
3697 Coverity, Inc. (http://scan.coverity.com).
3699 * When looking up multiply-defined global symbols, GDB will now prefer the
3700 symbol definition in the current shared library if it was built using the
3701 -Bsymbolic linker option.
3703 * When the Text User Interface (TUI) is not configured, GDB will now
3704 recognize the -tui command-line option and print a message that the TUI
3707 * The GDB remote stub, gdbserver, now has lower overhead for high
3708 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
3710 * GDB for MIPS targets now autodetects whether a remote target provides
3711 32-bit or 64-bit register values.
3713 * Support for C++ member pointers has been improved.
3715 * GDB now understands XML target descriptions, which specify the
3716 target's overall architecture. GDB can read a description from
3717 a local file or over the remote serial protocol.
3719 * Vectors of single-byte data use a new integer type which is not
3720 automatically displayed as character or string data.
3722 * The /s format now works with the print command. It displays
3723 arrays of single-byte integers and pointers to single-byte integers
3726 * Target descriptions can now describe target-specific registers,
3727 for architectures which have implemented the support (currently
3728 only ARM, M68K, and MIPS).
3730 * GDB and the GDB remote stub, gdbserver, now support the XScale
3733 * The GDB remote stub, gdbserver, has been updated to support
3734 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
3735 has been rewritten to use the standard GDB remote protocol.
3737 * GDB can now step into C++ functions which are called through thunks.
3739 * GDB for the Cell/B.E. SPU now supports overlay debugging.
3741 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
3742 layout. It also supports a TextSeg= and DataSeg= response when only
3743 segment base addresses (rather than offsets) are available.
3745 * The /i format now outputs any trailing branch delay slot instructions
3746 immediately following the last instruction within the count specified.
3748 * The GDB remote protocol "T" stop reply packet now supports a
3749 "library" response. Combined with the new "qXfer:libraries:read"
3750 packet, this response allows GDB to debug shared libraries on targets
3751 where the operating system manages the list of loaded libraries (e.g.
3752 Windows and SymbianOS).
3754 * The GDB remote stub, gdbserver, now supports dynamic link libraries
3755 (DLLs) on Windows and Windows CE targets.
3757 * GDB now supports a faster verification that a .debug file matches its binary
3758 according to its build-id signature, if the signature is present.
3764 Enable or disable hardware flow control (RTS/CTS) on the serial port
3765 when debugging using remote targets.
3767 set mem inaccessible-by-default
3768 show mem inaccessible-by-default
3769 If the target supplies a memory map, for instance via the remote
3770 protocol's "qXfer:memory-map:read" packet, setting this variable
3771 prevents GDB from accessing memory outside the memory map. This
3772 is useful for targets with memory mapped registers or which react
3773 badly to accesses of unmapped address space.
3775 set breakpoint auto-hw
3776 show breakpoint auto-hw
3777 If the target supplies a memory map, for instance via the remote
3778 protocol's "qXfer:memory-map:read" packet, setting this variable
3779 lets GDB use hardware breakpoints automatically for memory regions
3780 where it can not use software breakpoints. This covers both the
3781 "break" command and internal breakpoints used for other commands
3782 including "next" and "finish".
3785 catch exception unhandled
3786 Stop the program execution when Ada exceptions are raised.
3789 Stop the program execution when an Ada assertion failed.
3793 Set an alternate system root for target files. This is a more
3794 general version of "set solib-absolute-prefix", which is now
3795 an alias to "set sysroot".
3798 Provide extended SPU facility status information. This set of
3799 commands is available only when debugging the Cell/B.E. SPU
3802 * New native configurations
3804 OpenBSD/sh sh*-*openbsd*
3807 unset tdesc filename
3809 Use the specified local file as an XML target description, and do
3810 not query the target for its built-in description.
3814 OpenBSD/sh sh*-*-openbsd*
3815 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
3816 Toshiba Media Processor mep-elf
3818 * New remote packets
3821 Ignore the specified signals; pass them directly to the debugged program
3822 without stopping other threads or reporting them to GDB.
3824 qXfer:features:read:
3825 Read an XML target description from the target, which describes its
3830 Read or write contents of an spufs file on the target system. These
3831 packets are available only on the Cell/B.E. SPU architecture.
3833 qXfer:libraries:read:
3834 Report the loaded shared libraries. Combined with new "T" packet
3835 response, this packet allows GDB to debug shared libraries on
3836 targets where the operating system manages the list of loaded
3837 libraries (e.g. Windows and SymbianOS).
3841 Support for these obsolete configurations has been removed.
3849 i[34567]86-*-lynxos*
3850 i[34567]86-*-netware*
3851 i[34567]86-*-sco3.2v5*
3852 i[34567]86-*-sco3.2v4*
3854 i[34567]86-*-sysv4.2*
3857 i[34567]86-*-unixware2*
3858 i[34567]86-*-unixware*
3867 * Other removed features
3874 Various m68k-only ROM monitors.
3881 Various Renesas ROM monitors and debugging interfaces for SH and
3886 Support for a Macraigor serial interface to on-chip debugging.
3887 GDB does not directly support the newer parallel or USB
3892 A debug information format. The predecessor to DWARF 2 and
3893 DWARF 3, which are still supported.
3895 Support for the HP aCC compiler on HP-UX/PA-RISC
3897 SOM-encapsulated symbolic debugging information, automatic
3898 invocation of pxdb, and the aCC custom C++ ABI. This does not
3899 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
3900 with aCC can still be debugged on an assembly level.
3902 MIPS ".pdr" sections
3904 A MIPS-specific format used to describe stack frame layout
3905 in debugging information.
3909 GDB could work with an older version of Guile to debug
3910 the interpreter and Scheme programs running in it.
3912 set mips stack-arg-size
3913 set mips saved-gpreg-size
3915 Use "set mips abi" to control parameter passing for MIPS.
3917 *** Changes in GDB 6.6
3922 Cell Broadband Engine SPU spu-elf
3924 * GDB can now be configured as a cross-debugger targeting native Windows
3925 (mingw32) or Cygwin. It can communicate with a remote debugging stub
3926 running on a Windows system over TCP/IP to debug Windows programs.
3928 * The GDB remote stub, gdbserver, has been updated to support Windows and
3929 Cygwin debugging. Both single-threaded and multi-threaded programs are
3932 * The "set trust-readonly-sections" command works again. This command was
3933 broken in GDB 6.3, 6.4, and 6.5.
3935 * The "load" command now supports writing to flash memory, if the remote
3936 stub provides the required support.
3938 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
3939 longer requires symbolic debug information (e.g. DWARF-2).
3944 unset substitute-path
3945 show substitute-path
3946 Manage a list of substitution rules that GDB uses to rewrite the name
3947 of the directories where the sources are located. This can be useful
3948 for instance when the sources were moved to a different location
3949 between compilation and debugging.
3953 Print each CLI command as it is executed. Each command is prefixed with
3954 a number of `+' symbols representing the nesting depth.
3955 The source command now has a `-v' option to enable the same feature.
3959 The ARM Demon monitor support (RDP protocol, "target rdp").
3961 Kernel Object Display, an embedded debugging feature which only worked with
3962 an obsolete version of Cisco IOS.
3964 The 'set download-write-size' and 'show download-write-size' commands.
3966 * New remote packets
3969 Tell a stub about GDB client features, and request remote target features.
3970 The first feature implemented is PacketSize, which allows the target to
3971 specify the size of packets it can handle - to minimize the number of
3972 packets required and improve performance when connected to a remote
3976 Fetch an OS auxilliary vector from the remote stub. This packet is a
3977 more efficient replacement for qPart:auxv:read.
3979 qXfer:memory-map:read:
3980 Fetch a memory map from the remote stub, including information about
3981 RAM, ROM, and flash memory devices.
3986 Erase and program a flash memory device.
3988 * Removed remote packets
3991 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
3992 used it, and only gdbserver implemented it.
3994 *** Changes in GDB 6.5
3998 Renesas M32C/M16C m32c-elf
4000 Morpho Technologies ms1 ms1-elf
4004 init-if-undefined Initialize a convenience variable, but
4005 only if it doesn't already have a value.
4007 The following commands are presently only implemented for native GNU/Linux:
4009 checkpoint Save a snapshot of the program state.
4011 restart <n> Return the program state to a
4012 previously saved state.
4014 info checkpoints List currently saved checkpoints.
4016 delete-checkpoint <n> Delete a previously saved checkpoint.
4018 set|show detach-on-fork Tell gdb whether to detach from a newly
4019 forked process, or to keep debugging it.
4021 info forks List forks of the user program that
4022 are available to be debugged.
4024 fork <n> Switch to debugging one of several
4025 forks of the user program that are
4026 available to be debugged.
4028 delete-fork <n> Delete a fork from the list of forks
4029 that are available to be debugged (and
4030 kill the forked process).
4032 detach-fork <n> Delete a fork from the list of forks
4033 that are available to be debugged (and
4034 allow the process to continue).
4038 Morpho Technologies ms2 ms1-elf
4040 * Improved Windows host support
4042 GDB now builds as a cross debugger hosted on i686-mingw32, including
4043 native console support, and remote communications using either
4044 network sockets or serial ports.
4046 * Improved Modula-2 language support
4048 GDB can now print most types in the Modula-2 syntax. This includes:
4049 basic types, set types, record types, enumerated types, range types,
4050 pointer types and ARRAY types. Procedure var parameters are correctly
4051 printed and hexadecimal addresses and character constants are also
4052 written in the Modula-2 syntax. Best results can be obtained by using
4053 GNU Modula-2 together with the -gdwarf-2 command line option.
4057 The ARM rdi-share module.
4059 The Netware NLM debug server.
4061 *** Changes in GDB 6.4
4063 * New native configurations
4065 OpenBSD/arm arm*-*-openbsd*
4066 OpenBSD/mips64 mips64-*-openbsd*
4070 Morpho Technologies ms1 ms1-elf
4072 * New command line options
4074 --batch-silent As for --batch, but totally silent.
4075 --return-child-result The debugger will exist with the same value
4076 the child (debugged) program exited with.
4077 --eval-command COMMAND, -ex COMMAND
4078 Execute a single GDB CLI command. This may be
4079 specified multiple times and in conjunction
4080 with the --command (-x) option.
4082 * Deprecated commands removed
4084 The following commands, that were deprecated in 2000, have been
4088 set|show arm disassembly-flavor set|show arm disassembler
4089 othernames set arm disassembler
4090 set|show remotedebug set|show debug remote
4091 set|show archdebug set|show debug arch
4092 set|show eventdebug set|show debug event
4095 * New BSD user-level threads support
4097 It is now possible to debug programs using the user-level threads
4098 library on OpenBSD and FreeBSD. Currently supported (target)
4101 FreeBSD/amd64 x86_64-*-freebsd*
4102 FreeBSD/i386 i386-*-freebsd*
4103 OpenBSD/i386 i386-*-openbsd*
4105 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4106 are not yet supported.
4108 * New support for Matsushita MN10300 w/sim added
4109 (Work in progress). mn10300-elf.
4111 * REMOVED configurations and files
4113 VxWorks and the XDR protocol *-*-vxworks
4114 Motorola MCORE mcore-*-*
4115 National Semiconductor NS32000 ns32k-*-*
4117 * New "set print array-indexes" command
4119 After turning this setting "on", GDB prints the index of each element
4120 when displaying arrays. The default is "off" to preserve the previous
4123 * VAX floating point support
4125 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4127 * User-defined command support
4129 In addition to using $arg0..$arg9 for argument passing, it is now possible
4130 to use $argc to determine now many arguments have been passed. See the
4131 section on user-defined commands in the user manual for more information.
4133 *** Changes in GDB 6.3:
4135 * New command line option
4137 GDB now accepts -l followed by a number to set the timeout for remote
4140 * GDB works with GCC -feliminate-dwarf2-dups
4142 GDB now supports a more compact representation of DWARF-2 debug
4143 information using DW_FORM_ref_addr references. These are produced
4144 by GCC with the option -feliminate-dwarf2-dups and also by some
4145 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4146 to use -feliminate-dwarf2-dups.
4148 * Internationalization
4150 When supported by the host system, GDB will be built with
4151 internationalization (libintl). The task of marking up the sources is
4152 continued, we're looking forward to our first translation.
4156 Initial support for debugging programs compiled with the GNAT
4157 implementation of the Ada programming language has been integrated
4158 into GDB. In this release, support is limited to expression evaluation.
4160 * New native configurations
4162 GNU/Linux/m32r m32r-*-linux-gnu
4166 GDB's remote protocol now includes support for the 'p' packet. This
4167 packet is used to fetch individual registers from a remote inferior.
4169 * END-OF-LIFE registers[] compatibility module
4171 GDB's internal register infrastructure has been completely rewritten.
4172 The new infrastructure making possible the implementation of key new
4173 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4176 GDB 6.3 will be the last release to include the the registers[]
4177 compatibility module that allowed out-of-date configurations to
4178 continue to work. This change directly impacts the following
4188 powerpc bdm protocol
4190 Unless there is activity to revive these configurations, they will be
4191 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4193 * OBSOLETE configurations and files
4195 Configurations that have been declared obsolete in this release have
4196 been commented out. Unless there is activity to revive these
4197 configurations, the next release of GDB will have their sources
4198 permanently REMOVED.
4207 *** Changes in GDB 6.2.1:
4209 * MIPS `break main; run' gave an heuristic-fence-post warning
4211 When attempting to run even a simple program, a warning about
4212 heuristic-fence-post being hit would be reported. This problem has
4215 * MIPS IRIX 'long double' crashed GDB
4217 When examining a long double variable, GDB would get a segmentation
4218 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4219 IRIX long double values).
4223 A bug in the VAX stack code was causing problems with the "next"
4224 command. This problem has been fixed.
4226 *** Changes in GDB 6.2:
4228 * Fix for ``many threads''
4230 On GNU/Linux systems that use the NPTL threads library, a program
4231 rapidly creating and deleting threads would confuse GDB leading to the
4234 ptrace: No such process.
4235 thread_db_get_info: cannot get thread info: generic error
4237 This problem has been fixed.
4239 * "-async" and "-noasync" options removed.
4241 Support for the broken "-noasync" option has been removed (it caused
4244 * New ``start'' command.
4246 This command runs the program until the begining of the main procedure.
4248 * New BSD Kernel Data Access Library (libkvm) interface
4250 Using ``target kvm'' it is now possible to debug kernel core dumps and
4251 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4252 platforms. Currently supported (native-only) configurations are:
4254 FreeBSD/amd64 x86_64-*-freebsd*
4255 FreeBSD/i386 i?86-*-freebsd*
4256 NetBSD/i386 i?86-*-netbsd*
4257 NetBSD/m68k m68*-*-netbsd*
4258 NetBSD/sparc sparc-*-netbsd*
4259 OpenBSD/amd64 x86_64-*-openbsd*
4260 OpenBSD/i386 i?86-*-openbsd*
4261 OpenBSD/m68k m68*-openbsd*
4262 OpenBSD/sparc sparc-*-openbsd*
4264 * Signal trampoline code overhauled
4266 Many generic problems with GDB's signal handling code have been fixed.
4267 These include: backtraces through non-contiguous stacks; recognition
4268 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4269 call; backtrace through a signal trampoline; step into and out of
4270 signal handlers; and single-stepping in the signal trampoline.
4272 Please note that kernel bugs are a limiting factor here. These
4273 features have been shown to work on an s390 GNU/Linux system that
4274 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4276 * Cygwin support for DWARF 2 added.
4278 * New native configurations
4280 GNU/Linux/hppa hppa*-*-linux*
4281 OpenBSD/hppa hppa*-*-openbsd*
4282 OpenBSD/m68k m68*-*-openbsd*
4283 OpenBSD/m88k m88*-*-openbsd*
4284 OpenBSD/powerpc powerpc-*-openbsd*
4285 NetBSD/vax vax-*-netbsd*
4286 OpenBSD/vax vax-*-openbsd*
4288 * END-OF-LIFE frame compatibility module
4290 GDB's internal frame infrastructure has been completely rewritten.
4291 The new infrastructure making it possible to support key new features
4292 including DWARF 2 Call Frame Information. To aid in the task of
4293 migrating old configurations to this new infrastructure, a
4294 compatibility module, that allowed old configurations to continue to
4295 work, was also included.
4297 GDB 6.2 will be the last release to include this frame compatibility
4298 module. This change directly impacts the following configurations:
4308 Unless there is activity to revive these configurations, they will be
4309 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4311 * REMOVED configurations and files
4313 Sun 3, running SunOS 3 m68*-*-sunos3*
4314 Sun 3, running SunOS 4 m68*-*-sunos4*
4315 Sun 2, running SunOS 3 m68000-*-sunos3*
4316 Sun 2, running SunOS 4 m68000-*-sunos4*
4317 Motorola 680x0 running LynxOS m68*-*-lynxos*
4318 AT&T 3b1/Unix pc m68*-att-*
4319 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4320 decstation mips-dec-* mips-little-*
4321 riscos mips-*-riscos* mips-*-sysv*
4322 sonymips mips-sony-*
4323 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4325 *** Changes in GDB 6.1.1:
4327 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4329 The TUI (Text-mode User Interface) is now built as part of a default
4330 GDB configuration. It is enabled by either selecting the TUI with the
4331 command line option "-i=tui" or by running the separate "gdbtui"
4332 program. For more information on the TUI, see the manual "Debugging
4335 * Pending breakpoint support (also included in GDB 6.1)
4337 Support has been added to allow you to specify breakpoints in shared
4338 libraries that have not yet been loaded. If a breakpoint location
4339 cannot be found, and the "breakpoint pending" option is set to auto,
4340 GDB queries you if you wish to make the breakpoint pending on a future
4341 shared-library load. If and when GDB resolves the breakpoint symbol,
4342 the pending breakpoint is removed as one or more regular breakpoints
4345 Pending breakpoints are very useful for GCJ Java debugging.
4347 * Fixed ISO-C build problems
4349 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4350 non ISO-C code that stopped them being built using a more strict ISO-C
4351 compiler (e.g., IBM's C compiler).
4353 * Fixed build problem on IRIX 5
4355 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4356 wasn't able to compile compile on an IRIX 5 system.
4358 * Added execute permission to gdb/gdbserver/configure
4360 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4361 permission. This bug would cause configure to fail on a number of
4362 systems (Solaris, IRIX). Ref: server/519.
4364 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4366 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4367 has been updated to use constant array sizes.
4369 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4371 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4372 its generated DWARF Call Frame Info. This encoding was causing GDB to
4373 panic, that panic has been fixed. Ref: gdb/1628.
4375 * Fixed a problem when examining parameters in shared library code.
4377 When examining parameters in optimized shared library code generated
4378 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4379 not available''. GDB now correctly displays the variable's value.
4381 *** Changes in GDB 6.1:
4383 * Removed --with-mmalloc
4385 Support for the mmalloc memory manager has been removed, as it
4386 conflicted with the internal gdb byte cache.
4388 * Changes in AMD64 configurations
4390 The AMD64 target now includes the %cs and %ss registers. As a result
4391 the AMD64 remote protocol has changed; this affects the floating-point
4392 and SSE registers. If you rely on those registers for your debugging,
4393 you should upgrade gdbserver on the remote side.
4395 * Revised SPARC target
4397 The SPARC target has been completely revised, incorporating the
4398 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4399 support for LynxOS and SunOS 4 has been dropped. Calling functions
4400 from within GDB on operating systems with a non-executable stack
4401 (Solaris, OpenBSD) now works.
4405 GDB has a new C++ demangler which does a better job on the mangled
4406 names generated by current versions of g++. It also runs faster, so
4407 with this and other changes gdb should now start faster on large C++
4410 * DWARF 2 Location Expressions
4412 GDB support for location expressions has been extended to support function
4413 arguments and frame bases. Older versions of GDB could crash when they
4416 * C++ nested types and namespaces
4418 GDB's support for nested types and namespaces in C++ has been
4419 improved, especially if you use the DWARF 2 debugging format. (This
4420 is the default for recent versions of GCC on most platforms.)
4421 Specifically, if you have a class "Inner" defined within a class or
4422 namespace "Outer", then GDB realizes that the class's name is
4423 "Outer::Inner", not simply "Inner". This should greatly reduce the
4424 frequency of complaints about not finding RTTI symbols. In addition,
4425 if you are stopped at inside of a function defined within a namespace,
4426 GDB modifies its name lookup accordingly.
4428 * New native configurations
4430 NetBSD/amd64 x86_64-*-netbsd*
4431 OpenBSD/amd64 x86_64-*-openbsd*
4432 OpenBSD/alpha alpha*-*-openbsd*
4433 OpenBSD/sparc sparc-*-openbsd*
4434 OpenBSD/sparc64 sparc64-*-openbsd*
4436 * New debugging protocols
4438 M32R with SDI protocol m32r-*-elf*
4440 * "set prompt-escape-char" command deleted.
4442 The command "set prompt-escape-char" has been deleted. This command,
4443 and its very obscure effet on GDB's prompt, was never documented,
4444 tested, nor mentioned in the NEWS file.
4446 * OBSOLETE configurations and files
4448 Configurations that have been declared obsolete in this release have
4449 been commented out. Unless there is activity to revive these
4450 configurations, the next release of GDB will have their sources
4451 permanently REMOVED.
4453 Sun 3, running SunOS 3 m68*-*-sunos3*
4454 Sun 3, running SunOS 4 m68*-*-sunos4*
4455 Sun 2, running SunOS 3 m68000-*-sunos3*
4456 Sun 2, running SunOS 4 m68000-*-sunos4*
4457 Motorola 680x0 running LynxOS m68*-*-lynxos*
4458 AT&T 3b1/Unix pc m68*-att-*
4459 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4460 decstation mips-dec-* mips-little-*
4461 riscos mips-*-riscos* mips-*-sysv*
4462 sonymips mips-sony-*
4463 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4465 * REMOVED configurations and files
4467 SGI Irix-4.x mips-sgi-irix4 or iris4
4468 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4469 Z8000 simulator z8k-zilog-none or z8ksim
4470 Matsushita MN10200 w/simulator mn10200-*-*
4471 H8/500 simulator h8500-hitachi-hms or h8500hms
4472 HP/PA running BSD hppa*-*-bsd*
4473 HP/PA running OSF/1 hppa*-*-osf*
4474 HP/PA Pro target hppa*-*-pro*
4475 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4476 386BSD i[3456]86-*-bsd*
4477 Sequent family i[3456]86-sequent-sysv4*
4478 i[3456]86-sequent-sysv*
4479 i[3456]86-sequent-bsd*
4480 SPARC running LynxOS sparc-*-lynxos*
4481 SPARC running SunOS 4 sparc-*-sunos4*
4482 Tsqware Sparclet sparclet-*-*
4483 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4485 *** Changes in GDB 6.0:
4489 Support for debugging the Objective-C programming language has been
4490 integrated into GDB.
4492 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4494 DWARF 2's Call Frame Information makes available compiler generated
4495 information that more exactly describes the program's run-time stack.
4496 By using this information, GDB is able to provide more robust stack
4499 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
4500 have been updated to use a new backtrace mechanism which includes
4501 DWARF 2 CFI support.
4505 GDB's remote protocol has been extended to include support for hosted
4506 file I/O (where the remote target uses GDB's file system). See GDB's
4507 remote protocol documentation for details.
4509 * All targets using the new architecture framework.
4511 All of GDB's targets have been updated to use the new internal
4512 architecture framework. The way is now open for future GDB releases
4513 to include cross-architecture native debugging support (i386 on amd64,
4516 * GNU/Linux's Thread Local Storage (TLS)
4518 GDB now includes support for for the GNU/Linux implementation of
4519 per-thread variables.
4521 * GNU/Linux's Native POSIX Thread Library (NPTL)
4523 GDB's thread code has been updated to work with either the new
4524 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
4526 * Separate debug info.
4528 GDB, in conjunction with BINUTILS, now supports a mechanism for
4529 automatically loading debug information from a separate file. Instead
4530 of shipping full debug and non-debug versions of system libraries,
4531 system integrators can now instead ship just the stripped libraries
4532 and optional debug files.
4534 * DWARF 2 Location Expressions
4536 DWARF 2 Location Expressions allow the compiler to more completely
4537 describe the location of variables (even in optimized code) to the
4540 GDB now includes preliminary support for location expressions (support
4541 for DW_OP_piece is still missing).
4545 A number of long standing bugs that caused GDB to die while starting a
4546 Java application have been fixed. GDB's Java support is now
4547 considered "useable".
4549 * GNU/Linux support for fork, vfork, and exec.
4551 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
4552 commands are now implemented for GNU/Linux. They require a 2.5.x or later
4555 * GDB supports logging output to a file
4557 There are two new commands, "set logging" and "show logging", which can be
4558 used to capture GDB's output to a file.
4560 * The meaning of "detach" has changed for gdbserver
4562 The "detach" command will now resume the application, as documented. To
4563 disconnect from gdbserver and leave it stopped, use the new "disconnect"
4566 * d10v, m68hc11 `regs' command deprecated
4568 The `info registers' command has been updated so that it displays the
4569 registers using a format identical to the old `regs' command.
4573 A new command, "maint set profile on/off", has been added. This command can
4574 be used to enable or disable profiling while running GDB, to profile a
4575 session or a set of commands. In addition there is a new configure switch,
4576 "--enable-profiling", which will cause GDB to be compiled with profiling
4577 data, for more informative profiling results.
4579 * Default MI syntax changed to "mi2".
4581 The default MI (machine interface) syntax, enabled by the command line
4582 option "-i=mi", has been changed to "mi2". The previous MI syntax,
4583 "mi1", can be enabled by specifying the option "-i=mi1".
4585 Support for the original "mi0" syntax (included in GDB 5.0) has been
4588 Fix for gdb/192: removed extraneous space when displaying frame level.
4589 Fix for gdb/672: update changelist is now output in mi list format.
4590 Fix for gdb/702: a -var-assign that updates the value now shows up
4591 in a subsequent -var-update.
4593 * New native configurations.
4595 FreeBSD/amd64 x86_64-*-freebsd*
4597 * Multi-arched targets.
4599 HP/PA HPUX11 hppa*-*-hpux*
4600 Renesas M32R/D w/simulator m32r-*-elf*
4602 * OBSOLETE configurations and files
4604 Configurations that have been declared obsolete in this release have
4605 been commented out. Unless there is activity to revive these
4606 configurations, the next release of GDB will have their sources
4607 permanently REMOVED.
4609 Z8000 simulator z8k-zilog-none or z8ksim
4610 Matsushita MN10200 w/simulator mn10200-*-*
4611 H8/500 simulator h8500-hitachi-hms or h8500hms
4612 HP/PA running BSD hppa*-*-bsd*
4613 HP/PA running OSF/1 hppa*-*-osf*
4614 HP/PA Pro target hppa*-*-pro*
4615 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4616 Sequent family i[3456]86-sequent-sysv4*
4617 i[3456]86-sequent-sysv*
4618 i[3456]86-sequent-bsd*
4619 Tsqware Sparclet sparclet-*-*
4620 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4622 * REMOVED configurations and files
4625 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4626 IBM AIX PS/2 i[3456]86-*-aix
4627 i386 running Mach 3.0 i[3456]86-*-mach3*
4628 i386 running Mach i[3456]86-*-mach*
4629 i386 running OSF/1 i[3456]86-*osf1mk*
4630 HP/Apollo 68k Family m68*-apollo*-sysv*,
4632 m68*-hp-bsd*, m68*-hp-hpux*
4633 Argonaut Risc Chip (ARC) arc-*-*
4634 Mitsubishi D30V d30v-*-*
4635 Fujitsu FR30 fr30-*-elf*
4636 OS/9000 i[34]86-*-os9k
4637 I960 with MON960 i960-*-coff
4639 * MIPS $fp behavior changed
4641 The convenience variable $fp, for the MIPS, now consistently returns
4642 the address of the current frame's base. Previously, depending on the
4643 context, $fp could refer to either $sp or the current frame's base
4644 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
4645 The GNU Source-Level Debugger''.
4647 *** Changes in GDB 5.3:
4649 * GNU/Linux shared library multi-threaded performance improved.
4651 When debugging a multi-threaded application on GNU/Linux, GDB now uses
4652 `/proc', in preference to `ptrace' for memory reads. This may result
4653 in an improvement in the start-up time of multi-threaded, shared
4654 library applications when run under GDB. One GDB user writes: ``loads
4655 shared libs like mad''.
4657 * ``gdbserver'' now supports multi-threaded applications on some targets
4659 Support for debugging multi-threaded applications which use
4660 the GNU/Linux LinuxThreads package has been added for
4661 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
4662 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
4664 * GDB now supports C/C++ preprocessor macros.
4666 GDB now expands preprocessor macro invocations in C/C++ expressions,
4667 and provides various commands for showing macro definitions and how
4670 The new command `macro expand EXPRESSION' expands any macro
4671 invocations in expression, and shows the result.
4673 The new command `show macro MACRO-NAME' shows the definition of the
4674 macro named MACRO-NAME, and where it was defined.
4676 Most compilers don't include information about macros in the debugging
4677 information by default. In GCC 3.1, for example, you need to compile
4678 your program with the options `-gdwarf-2 -g3'. If the macro
4679 information is present in the executable, GDB will read it.
4681 * Multi-arched targets.
4683 DEC Alpha (partial) alpha*-*-*
4684 DEC VAX (partial) vax-*-*
4686 National Semiconductor NS32000 (partial) ns32k-*-*
4687 Motorola 68000 (partial) m68k-*-*
4688 Motorola MCORE mcore-*-*
4692 Fujitsu FRV architecture added by Red Hat frv*-*-*
4695 * New native configurations
4697 Alpha NetBSD alpha*-*-netbsd*
4698 SH NetBSD sh*-*-netbsdelf*
4699 MIPS NetBSD mips*-*-netbsd*
4700 UltraSPARC NetBSD sparc64-*-netbsd*
4702 * OBSOLETE configurations and files
4704 Configurations that have been declared obsolete in this release have
4705 been commented out. Unless there is activity to revive these
4706 configurations, the next release of GDB will have their sources
4707 permanently REMOVED.
4709 Mitsubishi D30V d30v-*-*
4710 OS/9000 i[34]86-*-os9k
4711 IBM AIX PS/2 i[3456]86-*-aix
4712 Fujitsu FR30 fr30-*-elf*
4713 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4714 Argonaut Risc Chip (ARC) arc-*-*
4715 i386 running Mach 3.0 i[3456]86-*-mach3*
4716 i386 running Mach i[3456]86-*-mach*
4717 i386 running OSF/1 i[3456]86-*osf1mk*
4718 HP/Apollo 68k Family m68*-apollo*-sysv*,
4720 m68*-hp-bsd*, m68*-hp-hpux*
4721 I960 with MON960 i960-*-coff
4723 * OBSOLETE languages
4725 CHILL, a Pascal like language used by telecommunications companies.
4727 * REMOVED configurations and files
4729 AMD 29k family via UDI a29k-amd-udi, udi29k
4730 A29K VxWorks a29k-*-vxworks
4731 AMD 29000 embedded, using EBMON a29k-none-none
4732 AMD 29000 embedded with COFF a29k-none-coff
4733 AMD 29000 embedded with a.out a29k-none-aout
4735 testsuite/gdb.hp/gdb.threads-hp/ directory
4737 * New command "set max-user-call-depth <nnn>"
4739 This command allows the user to limit the call depth of user-defined
4740 commands. The default is 1024.
4742 * Changes in FreeBSD/i386 native debugging.
4744 Support for the "generate-core-file" has been added.
4746 * New commands "dump", "append", and "restore".
4748 These commands allow data to be copied from target memory
4749 to a bfd-format or binary file (dump and append), and back
4750 from a file into memory (restore).
4752 * Improved "next/step" support on multi-processor Alpha Tru64.
4754 The previous single-step mechanism could cause unpredictable problems,
4755 including the random appearance of SIGSEGV or SIGTRAP signals. The use
4756 of a software single-step mechanism prevents this.
4758 *** Changes in GDB 5.2.1:
4766 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
4767 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
4768 Fix, by Joel Brobecker imported from mainline.
4770 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
4771 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
4772 Fix, by Fred Fish, imported from mainline.
4774 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
4775 Surprisingly enough, it works now.
4776 By Michal Ludvig, imported from mainline.
4778 i386 hardware watchpoint support:
4779 avoid misses on second run for some targets.
4780 By Pierre Muller, imported from mainline.
4782 *** Changes in GDB 5.2:
4784 * New command "set trust-readonly-sections on[off]".
4786 This command is a hint that tells gdb that read-only sections
4787 really are read-only (ie. that their contents will not change).
4788 In this mode, gdb will go to the object file rather than the
4789 target to read memory from read-only sections (such as ".text").
4790 This can be a significant performance improvement on some
4791 (notably embedded) targets.
4793 * New command "generate-core-file" (or "gcore").
4795 This new gdb command allows the user to drop a core file of the child
4796 process state at any time. So far it's been implemented only for
4797 GNU/Linux and Solaris, but should be relatively easily ported to other
4798 hosts. Argument is core file name (defaults to core.<pid>).
4800 * New command line option
4802 GDB now accepts --pid or -p followed by a process id.
4804 * Change in command line behavior -- corefiles vs. process ids.
4806 There is a subtle behavior in the way in which GDB handles
4807 command line arguments. The first non-flag argument is always
4808 a program to debug, but the second non-flag argument may either
4809 be a corefile or a process id. Previously, GDB would attempt to
4810 open the second argument as a corefile, and if that failed, would
4811 issue a superfluous error message and then attempt to attach it as
4812 a process. Now, if the second argument begins with a non-digit,
4813 it will be treated as a corefile. If it begins with a digit,
4814 GDB will attempt to attach it as a process, and if no such process
4815 is found, will then attempt to open it as a corefile.
4817 * Changes in ARM configurations.
4819 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
4820 configuration is fully multi-arch.
4822 * New native configurations
4824 ARM NetBSD arm*-*-netbsd*
4825 x86 OpenBSD i[3456]86-*-openbsd*
4826 AMD x86-64 running GNU/Linux x86_64-*-linux-*
4827 Sparc64 running FreeBSD sparc64-*-freebsd*
4831 Sanyo XStormy16 xstormy16-elf
4833 * OBSOLETE configurations and files
4835 Configurations that have been declared obsolete in this release have
4836 been commented out. Unless there is activity to revive these
4837 configurations, the next release of GDB will have their sources
4838 permanently REMOVED.
4840 AMD 29k family via UDI a29k-amd-udi, udi29k
4841 A29K VxWorks a29k-*-vxworks
4842 AMD 29000 embedded, using EBMON a29k-none-none
4843 AMD 29000 embedded with COFF a29k-none-coff
4844 AMD 29000 embedded with a.out a29k-none-aout
4846 testsuite/gdb.hp/gdb.threads-hp/ directory
4848 * REMOVED configurations and files
4850 TI TMS320C80 tic80-*-*
4852 PowerPC Solaris powerpcle-*-solaris*
4853 PowerPC Windows NT powerpcle-*-cygwin32
4854 PowerPC Netware powerpc-*-netware*
4855 Harris/CXUX m88k m88*-harris-cxux*
4856 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4857 ns32k-utek-sysv* ns32k-utek-*
4858 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4859 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4860 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4861 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4862 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
4864 * Changes to command line processing
4866 The new `--args' feature can be used to specify command-line arguments
4867 for the inferior from gdb's command line.
4869 * Changes to key bindings
4871 There is a new `operate-and-get-next' function bound to `C-o'.
4873 *** Changes in GDB 5.1.1
4875 Fix compile problem on DJGPP.
4877 Fix a problem with floating-point registers on the i386 being
4880 Fix to stop GDB crashing on .debug_str debug info.
4882 Numerous documentation fixes.
4884 Numerous testsuite fixes.
4886 *** Changes in GDB 5.1:
4888 * New native configurations
4890 Alpha FreeBSD alpha*-*-freebsd*
4891 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
4892 MIPS GNU/Linux mips*-*-linux*
4893 MIPS SGI Irix 6.x mips*-sgi-irix6*
4894 ia64 AIX ia64-*-aix*
4895 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
4899 Motorola 68HC11 and 68HC12 m68hc11-elf
4901 UltraSparc running GNU/Linux sparc64-*-linux*
4903 * OBSOLETE configurations and files
4905 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
4906 Harris/CXUX m88k m88*-harris-cxux*
4907 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
4908 ns32k-utek-sysv* ns32k-utek-*
4909 TI TMS320C80 tic80-*-*
4911 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
4912 PowerPC Solaris powerpcle-*-solaris*
4913 PowerPC Windows NT powerpcle-*-cygwin32
4914 PowerPC Netware powerpc-*-netware*
4915 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
4916 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
4917 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
4918 Apple Macintosh (MPW) host N/A
4920 stuff.c (Program to stuff files into a specially prepared space in kdb)
4921 kdb-start.c (Main loop for the standalone kernel debugger)
4923 Configurations that have been declared obsolete in this release have
4924 been commented out. Unless there is activity to revive these
4925 configurations, the next release of GDB will have their sources
4926 permanently REMOVED.
4928 * REMOVED configurations and files
4930 Altos 3068 m68*-altos-*
4931 Convex c1-*-*, c2-*-*
4933 ARM RISCix arm-*-* (as host)
4937 * GDB has been converted to ISO C.
4939 GDB's source code has been converted to ISO C. In particular, the
4940 sources are fully protoized, and rely on standard headers being
4945 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
4947 * The MI enabled by default.
4949 The new machine oriented interface (MI) introduced in GDB 5.0 has been
4950 revised and enabled by default. Packages which use GDB as a debugging
4951 engine behind a UI or another front end are encouraged to switch to
4952 using the GDB/MI interface, instead of the old annotations interface
4953 which is now deprecated.
4955 * Support for debugging Pascal programs.
4957 GDB now includes support for debugging Pascal programs. The following
4958 main features are supported:
4960 - Pascal-specific data types such as sets;
4962 - automatic recognition of Pascal sources based on file-name
4965 - Pascal-style display of data types, variables, and functions;
4967 - a Pascal expression parser.
4969 However, some important features are not yet supported.
4971 - Pascal string operations are not supported at all;
4973 - there are some problems with boolean types;
4975 - Pascal type hexadecimal constants are not supported
4976 because they conflict with the internal variables format;
4978 - support for Pascal objects and classes is not full yet;
4980 - unlike Pascal, GDB is case-sensitive for symbol names.
4982 * Changes in completion.
4984 Commands such as `shell', `run' and `set args', which pass arguments
4985 to inferior programs, now complete on file names, similar to what
4986 users expect at the shell prompt.
4988 Commands which accept locations, such as `disassemble', `print',
4989 `breakpoint', `until', etc. now complete on filenames as well as
4990 program symbols. Thus, if you type "break foob TAB", and the source
4991 files linked into the programs include `foobar.c', that file name will
4992 be one of the candidates for completion. However, file names are not
4993 considered for completion after you typed a colon that delimits a file
4994 name from a name of a function in that file, as in "break foo.c:bar".
4996 `set demangle-style' completes on available demangling styles.
4998 * New platform-independent commands:
5000 It is now possible to define a post-hook for a command as well as a
5001 hook that runs before the command. For more details, see the
5002 documentation of `hookpost' in the GDB manual.
5004 * Changes in GNU/Linux native debugging.
5006 Support for debugging multi-threaded programs has been completely
5007 revised for all platforms except m68k and sparc. You can now debug as
5008 many threads as your system allows you to have.
5010 Attach/detach is supported for multi-threaded programs.
5012 Support for SSE registers was added for x86. This doesn't work for
5013 multi-threaded programs though.
5015 * Changes in MIPS configurations.
5017 Multi-arch support is enabled for all MIPS configurations.
5019 GDB can now be built as native debugger on SGI Irix 6.x systems for
5020 debugging n32 executables. (Debugging 64-bit executables is not yet
5023 * Unified support for hardware watchpoints in all x86 configurations.
5025 Most (if not all) native x86 configurations support hardware-assisted
5026 breakpoints and watchpoints in a unified manner. This support
5027 implements debug register sharing between watchpoints, which allows to
5028 put a virtually infinite number of watchpoints on the same address,
5029 and also supports watching regions up to 16 bytes with several debug
5032 The new maintenance command `maintenance show-debug-regs' toggles
5033 debugging print-outs in functions that insert, remove, and test
5034 watchpoints and hardware breakpoints.
5036 * Changes in the DJGPP native configuration.
5038 New command ``info dos sysinfo'' displays assorted information about
5039 the CPU, OS, memory, and DPMI server.
5041 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5042 display information about segment descriptors stored in GDT, LDT, and
5045 New commands ``info dos pde'' and ``info dos pte'' display entries
5046 from Page Directory and Page Tables (for now works with CWSDPMI only).
5047 New command ``info dos address-pte'' displays the Page Table entry for
5048 a given linear address.
5050 GDB can now pass command lines longer than 126 characters to the
5051 program being debugged (requires an update to the libdbg.a library
5052 which is part of the DJGPP development kit).
5054 DWARF2 debug info is now supported.
5056 It is now possible to `step' and `next' through calls to `longjmp'.
5058 * Changes in documentation.
5060 All GDB documentation was converted to GFDL, the GNU Free
5061 Documentation License.
5063 Tracepoints-related commands are now fully documented in the GDB
5066 TUI, the Text-mode User Interface, is now documented in the manual.
5068 Tracepoints-related commands are now fully documented in the GDB
5071 The "GDB Internals" manual now has an index. It also includes
5072 documentation of `ui_out' functions, GDB coding standards, x86
5073 hardware watchpoints, and memory region attributes.
5075 * GDB's version number moved to ``version.in''
5077 The Makefile variable VERSION has been replaced by the file
5078 ``version.in''. People creating GDB distributions should update the
5079 contents of this file.
5083 GUD support is now a standard part of the EMACS distribution.
5085 *** Changes in GDB 5.0:
5087 * Improved support for debugging FP programs on x86 targets
5089 Unified and much-improved support for debugging floating-point
5090 programs on all x86 targets. In particular, ``info float'' now
5091 displays the FP registers in the same format on all x86 targets, with
5092 greater level of detail.
5094 * Improvements and bugfixes in hardware-assisted watchpoints
5096 It is now possible to watch array elements, struct members, and
5097 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5098 on x86 targets no longer erroneously trigger when the address is
5101 * Improvements in the native DJGPP version of GDB
5103 The distribution now includes all the scripts and auxiliary files
5104 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5105 machines ``out of the box''.
5107 The DJGPP version can now debug programs that use signals. It is
5108 possible to catch signals that happened in the debuggee, deliver
5109 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5110 would kill the program being debugged.) Programs that hook hardware
5111 interrupts (keyboard, timer, etc.) can also be debugged.
5113 It is now possible to debug DJGPP programs that redirect their
5114 standard handles or switch them to raw (as opposed to cooked) mode, or
5115 even close them. The command ``run < foo > bar'' works as expected,
5116 and ``info terminal'' reports useful information about the debuggee's
5117 terminal, including raw/cooked mode, redirection, etc.
5119 The DJGPP version now uses termios functions for console I/O, which
5120 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5123 DOS-style file names with drive letters are now fully supported by
5126 It is now possible to debug DJGPP programs that switch their working
5127 directory. It is also possible to rerun the debuggee any number of
5128 times without restarting GDB; thus, you can use the same setup,
5129 breakpoints, etc. for many debugging sessions.
5131 * New native configurations
5133 ARM GNU/Linux arm*-*-linux*
5134 PowerPC GNU/Linux powerpc-*-linux*
5138 Motorola MCore mcore-*-*
5139 x86 VxWorks i[3456]86-*-vxworks*
5140 PowerPC VxWorks powerpc-*-vxworks*
5141 TI TMS320C80 tic80-*-*
5143 * OBSOLETE configurations
5145 Altos 3068 m68*-altos-*
5146 Convex c1-*-*, c2-*-*
5148 ARM RISCix arm-*-* (as host)
5151 Configurations that have been declared obsolete will be commented out,
5152 but the code will be left in place. If there is no activity to revive
5153 these configurations before the next release of GDB, the sources will
5154 be permanently REMOVED.
5156 * Gould support removed
5158 Support for the Gould PowerNode and NP1 has been removed.
5160 * New features for SVR4
5162 On SVR4 native platforms (such as Solaris), if you attach to a process
5163 without first loading a symbol file, GDB will now attempt to locate and
5164 load symbols from the running process's executable file.
5166 * Many C++ enhancements
5168 C++ support has been greatly improved. Overload resolution now works properly
5169 in almost all cases. RTTI support is on the way.
5171 * Remote targets can connect to a sub-program
5173 A popen(3) style serial-device has been added. This device starts a
5174 sub-process (such as a stand-alone simulator) and then communicates
5175 with that. The sub-program to run is specified using the syntax
5176 ``|<program> <args>'' vis:
5178 (gdb) set remotedebug 1
5179 (gdb) target extended-remote |mn10300-elf-sim program-args
5181 * MIPS 64 remote protocol
5183 A long standing bug in the mips64 remote protocol where by GDB
5184 expected certain 32 bit registers (ex SR) to be transfered as 32
5185 instead of 64 bits has been fixed.
5187 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5188 added to provide backward compatibility with older versions of GDB.
5190 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5192 The command ``set remotebinarydownload'' command has been replaced by
5193 ``set remote X-packet''. Other commands in ``set remote'' family
5194 include ``set remote P-packet''.
5196 * Breakpoint commands accept ranges.
5198 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5199 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5200 ``tracepoint passcount'' also accepts a range of tracepoints.
5202 * ``apropos'' command added.
5204 The ``apropos'' command searches through command names and
5205 documentation strings, printing out matches, making it much easier to
5206 try to find a command that does what you are looking for.
5210 A new machine oriented interface (MI) has been added to GDB. This
5211 interface is designed for debug environments running GDB as a separate
5212 process. This is part of the long term libGDB project. See the
5213 "GDB/MI" chapter of the GDB manual for further information. It can be
5214 enabled by configuring with:
5216 .../configure --enable-gdbmi
5218 *** Changes in GDB-4.18:
5220 * New native configurations
5222 HP-UX 10.20 hppa*-*-hpux10.20
5223 HP-UX 11.x hppa*-*-hpux11.0*
5224 M68K GNU/Linux m68*-*-linux*
5228 Fujitsu FR30 fr30-*-elf*
5229 Intel StrongARM strongarm-*-*
5230 Mitsubishi D30V d30v-*-*
5232 * OBSOLETE configurations
5234 Gould PowerNode, NP1 np1-*-*, pn-*-*
5236 Configurations that have been declared obsolete will be commented out,
5237 but the code will be left in place. If there is no activity to revive
5238 these configurations before the next release of GDB, the sources will
5239 be permanently REMOVED.
5243 As a compatibility experiment, GDB's source files buildsym.h and
5244 buildsym.c have been converted to pure standard C, no longer
5245 containing any K&R compatibility code. We believe that all systems in
5246 use today either come with a standard C compiler, or have a GCC port
5247 available. If this is not true, please report the affected
5248 configuration to bug-gdb@gnu.org immediately. See the README file for
5249 information about getting a standard C compiler if you don't have one
5254 GDB now uses readline 2.2.
5256 * set extension-language
5258 You can now control the mapping between filename extensions and source
5259 languages by using the `set extension-language' command. For instance,
5260 you can ask GDB to treat .c files as C++ by saying
5261 set extension-language .c c++
5262 The command `info extensions' lists all of the recognized extensions
5263 and their associated languages.
5265 * Setting processor type for PowerPC and RS/6000
5267 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5268 you can use the `set processor' command to specify what variant of the
5269 PowerPC family you are debugging. The command
5273 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5274 following PowerPC and RS6000 variants:
5276 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5277 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5279 403GC IBM PowerPC 403GC
5280 505 Motorola PowerPC 505
5281 860 Motorola PowerPC 860 or 850
5282 601 Motorola PowerPC 601
5283 602 Motorola PowerPC 602
5284 603 Motorola/IBM PowerPC 603 or 603e
5285 604 Motorola PowerPC 604 or 604e
5286 750 Motorola/IBM PowerPC 750 or 750
5288 At the moment, this command just tells GDB what to name the
5289 special-purpose processor registers. Since almost all the affected
5290 registers are inaccessible to user-level programs, this command is
5291 only useful for remote debugging in its present form.
5295 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5296 more extensive support for HP-UX. Added features include shared
5297 library support, kernel threads and hardware watchpoints for 11.00,
5298 support for HP's ANSI C and C++ compilers, and a compatibility mode
5299 for xdb and dbx commands.
5303 HP's donation includes the new concept of catchpoints, which is a
5304 generalization of the old catch command. On HP-UX, it is now possible
5305 to catch exec, fork, and vfork, as well as library loading.
5307 This means that the existing catch command has changed; its first
5308 argument now specifies the type of catch to be set up. See the
5309 output of "help catch" for a list of catchpoint types.
5311 * Debugging across forks
5313 On HP-UX, you can choose which process to debug when a fork() happens
5318 HP has donated a curses-based terminal user interface (TUI). To get
5319 it, build with --enable-tui. Although this can be enabled for any
5320 configuration, at present it only works for native HP debugging.
5322 * GDB remote protocol additions
5324 A new protocol packet 'X' that writes binary data is now available.
5325 Default behavior is to try 'X', then drop back to 'M' if the stub
5326 fails to respond. The settable variable `remotebinarydownload'
5327 allows explicit control over the use of 'X'.
5329 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5330 full 64-bit address. The command
5332 set remoteaddresssize 32
5334 can be used to revert to the old behaviour. For existing remote stubs
5335 the change should not be noticed, as the additional address information
5338 In order to assist in debugging stubs, you may use the maintenance
5339 command `packet' to send any text string to the stub. For instance,
5341 maint packet heythere
5343 sends the packet "$heythere#<checksum>". Note that it is very easy to
5344 disrupt a debugging session by sending the wrong packet at the wrong
5347 The compare-sections command allows you to compare section data on the
5348 target to what is in the executable file without uploading or
5349 downloading, by comparing CRC checksums.
5351 * Tracing can collect general expressions
5353 You may now collect general expressions at tracepoints. This requires
5354 further additions to the target-side stub; see tracepoint.c and
5355 doc/agentexpr.texi for further details.
5357 * mask-address variable for Mips
5359 For Mips targets, you may control the zeroing of the upper 32 bits of
5360 a 64-bit address by entering `set mask-address on'. This is mainly
5361 of interest to users of embedded R4xxx and R5xxx processors.
5363 * Higher serial baud rates
5365 GDB's serial code now allows you to specify baud rates 57600, 115200,
5366 230400, and 460800 baud. (Note that your host system may not be able
5367 to achieve all of these rates.)
5371 The i960 configuration now includes an initial implementation of a
5372 builtin simulator, contributed by Jim Wilson.
5375 *** Changes in GDB-4.17:
5377 * New native configurations
5379 Alpha GNU/Linux alpha*-*-linux*
5380 Unixware 2.x i[3456]86-unixware2*
5381 Irix 6.x mips*-sgi-irix6*
5382 PowerPC GNU/Linux powerpc-*-linux*
5383 PowerPC Solaris powerpcle-*-solaris*
5384 Sparc GNU/Linux sparc-*-linux*
5385 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5389 Argonaut Risc Chip (ARC) arc-*-*
5390 Hitachi H8/300S h8300*-*-*
5391 Matsushita MN10200 w/simulator mn10200-*-*
5392 Matsushita MN10300 w/simulator mn10300-*-*
5393 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5394 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5395 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5396 Mitsubishi D10V w/simulator d10v-*-*
5397 Mitsubishi M32R/D w/simulator m32r-*-elf*
5398 Tsqware Sparclet sparclet-*-*
5399 NEC V850 w/simulator v850-*-*
5401 * New debugging protocols
5403 ARM with RDI protocol arm*-*-*
5404 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5405 DDB and LSI variants of PMON protocol mips*-*-*
5406 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5407 PowerPC with SDS protocol powerpc{,le}-*-eabi
5408 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5412 All configurations can now understand and use the DWARF 2 debugging
5413 format. The choice is automatic, if the symbol file contains DWARF 2
5418 GDB now includes basic Java language support. This support is
5419 only useful with Java compilers that produce native machine code.
5421 * solib-absolute-prefix and solib-search-path
5423 For SunOS and SVR4 shared libraries, you may now set the prefix for
5424 loading absolute shared library symbol files, and the search path for
5425 locating non-absolute shared library symbol files.
5427 * Live range splitting
5429 GDB can now effectively debug code for which GCC has performed live
5430 range splitting as part of its optimization. See gdb/doc/LRS for
5431 more details on the expected format of the stabs information.
5435 GDB's support for the GNU Hurd, including thread debugging, has been
5436 updated to work with current versions of the Hurd.
5440 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5441 instruction set. ARM GDB automatically detects when Thumb
5442 instructions are in use, and adjusts disassembly and backtracing
5447 GDB's MIPS target configurations now handle the MIP16 16-bit
5452 GDB now includes support for overlays; if an executable has been
5453 linked such that multiple sections are based at the same address, GDB
5454 will decide which section to use for symbolic info. You can choose to
5455 control the decision manually, using overlay commands, or implement
5456 additional target-side support and use "overlay load-target" to bring
5457 in the overlay mapping. Do "help overlay" for more detail.
5461 The command "info symbol <address>" displays information about
5462 the symbol at the specified address.
5466 The standard remote protocol now includes an extension that allows
5467 asynchronous collection and display of trace data. This requires
5468 extensive support in the target-side debugging stub. Tracing mode
5469 includes a new interaction mode in GDB and new commands: see the
5470 file tracepoint.c for more details.
5474 Configurations for embedded MIPS now include a simulator contributed
5475 by Cygnus Solutions. The simulator supports the instruction sets
5476 of most MIPS variants.
5480 Sparc configurations may now include the ERC32 simulator contributed
5481 by the European Space Agency. The simulator is not built into
5482 Sparc targets by default; configure with --enable-sim to include it.
5486 For target configurations that may include multiple variants of a
5487 basic architecture (such as MIPS and SH), you may now set the
5488 architecture explicitly. "set arch" sets, "info arch" lists
5489 the possible architectures.
5491 *** Changes in GDB-4.16:
5493 * New native configurations
5495 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5496 M68K NetBSD m68k-*-netbsd*
5497 PowerPC AIX 4.x powerpc-*-aix*
5498 PowerPC MacOS powerpc-*-macos*
5499 PowerPC Windows NT powerpcle-*-cygwin32
5500 RS/6000 AIX 4.x rs6000-*-aix4*
5504 ARM with RDP protocol arm-*-*
5505 I960 with MON960 i960-*-coff
5506 MIPS VxWorks mips*-*-vxworks*
5507 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
5508 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
5510 Matra Sparclet sparclet-*-*
5514 The powerpc-eabi configuration now includes the PSIM simulator,
5515 contributed by Andrew Cagney, with assistance from Mike Meissner.
5516 PSIM is a very elaborate model of the PowerPC, including not only
5517 basic instruction set execution, but also details of execution unit
5518 performance and I/O hardware. See sim/ppc/README for more details.
5522 GDB now works with Solaris 2.5.
5524 * Windows 95/NT native
5526 GDB will now work as a native debugger on Windows 95 and Windows NT.
5527 To build it from source, you must use the "gnu-win32" environment,
5528 which uses a DLL to emulate enough of Unix to run the GNU tools.
5529 Further information, binaries, and sources are available at
5530 ftp.cygnus.com, under pub/gnu-win32.
5532 * dont-repeat command
5534 If a user-defined command includes the command `dont-repeat', then the
5535 command will not be repeated if the user just types return. This is
5536 useful if the command is time-consuming to run, so that accidental
5537 extra keystrokes don't run the same command many times.
5539 * Send break instead of ^C
5541 The standard remote protocol now includes an option to send a break
5542 rather than a ^C to the target in order to interrupt it. By default,
5543 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
5545 * Remote protocol timeout
5547 The standard remote protocol includes a new variable `remotetimeout'
5548 that allows you to set the number of seconds before GDB gives up trying
5549 to read from the target. The default value is 2.
5551 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
5553 By default GDB will automatically keep track of objects as they are
5554 loaded and unloaded by the dynamic linker. By using the command `set
5555 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
5556 when shared library events occur, thus allowing you to set breakpoints
5557 in shared libraries which are explicitly loaded by the inferior.
5559 Note this feature does not work on hpux8. On hpux9 you must link
5560 /usr/lib/end.o into your program. This feature should work
5561 automatically on hpux10.
5563 * Irix 5.x hardware watchpoint support
5565 Irix 5 configurations now support the use of hardware watchpoints.
5567 * Mips protocol "SYN garbage limit"
5569 When debugging a Mips target using the `target mips' protocol, you
5570 may set the number of characters that GDB will ignore by setting
5571 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
5572 every character. The default value is 1050.
5574 * Recording and replaying remote debug sessions
5576 If you set `remotelogfile' to the name of a file, gdb will write to it
5577 a recording of a remote debug session. This recording may then be
5578 replayed back to gdb using "gdbreplay". See gdbserver/README for
5579 details. This is useful when you have a problem with GDB while doing
5580 remote debugging; you can make a recording of the session and send it
5581 to someone else, who can then recreate the problem.
5583 * Speedups for remote debugging
5585 GDB includes speedups for downloading and stepping MIPS systems using
5586 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
5587 and more efficient S-record downloading.
5589 * Memory use reductions and statistics collection
5591 GDB now uses less memory and reports statistics about memory usage.
5592 Try the `maint print statistics' command, for example.
5594 *** Changes in GDB-4.15:
5596 * Psymtabs for XCOFF
5598 The symbol reader for AIX GDB now uses partial symbol tables. This
5599 can greatly improve startup time, especially for large executables.
5601 * Remote targets use caching
5603 Remote targets now use a data cache to speed up communication with the
5604 remote side. The data cache could lead to incorrect results because
5605 it doesn't know about volatile variables, thus making it impossible to
5606 debug targets which use memory mapped I/O devices. `set remotecache
5607 off' turns the the data cache off.
5609 * Remote targets may have threads
5611 The standard remote protocol now includes support for multiple threads
5612 in the target system, using new protocol commands 'H' and 'T'. See
5613 gdb/remote.c for details.
5617 If GDB is configured with `--enable-netrom', then it will include
5618 support for the NetROM ROM emulator from XLNT Designs. The NetROM
5619 acts as though it is a bank of ROM on the target board, but you can
5620 write into it over the network. GDB's support consists only of
5621 support for fast loading into the emulated ROM; to debug, you must use
5622 another protocol, such as standard remote protocol. The usual
5623 sequence is something like
5625 target nrom <netrom-hostname>
5627 target remote <netrom-hostname>:1235
5631 GDB now includes support for the Apple Macintosh, as a host only. It
5632 may be run as either an MPW tool or as a standalone application, and
5633 it can debug through the serial port. All the usual GDB commands are
5634 available, but to the target command, you must supply "serial" as the
5635 device type instead of "/dev/ttyXX". See mpw-README in the main
5636 directory for more information on how to build. The MPW configuration
5637 scripts */mpw-config.in support only a few targets, and only the
5638 mips-idt-ecoff target has been tested.
5642 GDB configuration now uses autoconf. This is not user-visible,
5643 but does simplify configuration and building.
5647 GDB now supports hpux10.
5649 *** Changes in GDB-4.14:
5651 * New native configurations
5653 x86 FreeBSD i[345]86-*-freebsd
5654 x86 NetBSD i[345]86-*-netbsd
5655 NS32k NetBSD ns32k-*-netbsd
5656 Sparc NetBSD sparc-*-netbsd
5660 A29K VxWorks a29k-*-vxworks
5661 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
5662 CPU32 EST-300 emulator m68*-*-est*
5663 PowerPC ELF powerpc-*-elf
5666 * Alpha OSF/1 support for procfs
5668 GDB now supports procfs under OSF/1-2.x and higher, which makes it
5669 possible to attach to running processes. As the mounting of the /proc
5670 filesystem is optional on the Alpha, GDB automatically determines
5671 the availability of /proc during startup. This can lead to problems
5672 if /proc is unmounted after GDB has been started.
5674 * Arguments to user-defined commands
5676 User commands may accept up to 10 arguments separated by whitespace.
5677 Arguments are accessed within the user command via $arg0..$arg9. A
5680 print $arg0 + $arg1 + $arg2
5682 To execute the command use:
5685 Defines the command "adder" which prints the sum of its three arguments.
5686 Note the arguments are text substitutions, so they may reference variables,
5687 use complex expressions, or even perform inferior function calls.
5689 * New `if' and `while' commands
5691 This makes it possible to write more sophisticated user-defined
5692 commands. Both commands take a single argument, which is the
5693 expression to evaluate, and must be followed by the commands to
5694 execute, one per line, if the expression is nonzero, the list being
5695 terminated by the word `end'. The `if' command list may include an
5696 `else' word, which causes the following commands to be executed only
5697 if the expression is zero.
5699 * Fortran source language mode
5701 GDB now includes partial support for Fortran 77. It will recognize
5702 Fortran programs and can evaluate a subset of Fortran expressions, but
5703 variables and functions may not be handled correctly. GDB will work
5704 with G77, but does not yet know much about symbols emitted by other
5707 * Better HPUX support
5709 Most debugging facilities now work on dynamic executables for HPPAs
5710 running hpux9 or later. You can attach to running dynamically linked
5711 processes, but by default the dynamic libraries will be read-only, so
5712 for instance you won't be able to put breakpoints in them. To change
5713 that behavior do the following before running the program:
5719 This will cause the libraries to be mapped private and read-write.
5720 To revert to the normal behavior, do this:
5726 You cannot set breakpoints or examine data in the library until after
5727 the library is loaded if the function/data symbols do not have
5730 GDB can now also read debug symbols produced by the HP C compiler on
5731 HPPAs (sorry, no C++, Fortran or 68k support).
5733 * Target byte order now dynamically selectable
5735 You can choose which byte order to use with a target system, via the
5736 commands "set endian big" and "set endian little", and you can see the
5737 current setting by using "show endian". You can also give the command
5738 "set endian auto", in which case GDB will use the byte order
5739 associated with the executable. Currently, only embedded MIPS
5740 configurations support dynamic selection of target byte order.
5742 * New DOS host serial code
5744 This version uses DPMI interrupts to handle buffered I/O, so you
5745 no longer need to run asynctsr when debugging boards connected to
5748 *** Changes in GDB-4.13:
5750 * New "complete" command
5752 This lists all the possible completions for the rest of the line, if it
5753 were to be given as a command itself. This is intended for use by emacs.
5755 * Trailing space optional in prompt
5757 "set prompt" no longer adds a space for you after the prompt you set. This
5758 allows you to set a prompt which ends in a space or one that does not.
5760 * Breakpoint hit counts
5762 "info break" now displays a count of the number of times the breakpoint
5763 has been hit. This is especially useful in conjunction with "ignore"; you
5764 can ignore a large number of breakpoint hits, look at the breakpoint info
5765 to see how many times the breakpoint was hit, then run again, ignoring one
5766 less than that number, and this will get you quickly to the last hit of
5769 * Ability to stop printing at NULL character
5771 "set print null-stop" will cause GDB to stop printing the characters of
5772 an array when the first NULL is encountered. This is useful when large
5773 arrays actually contain only short strings.
5775 * Shared library breakpoints
5777 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
5778 breakpoints in shared libraries before the executable is run.
5780 * Hardware watchpoints
5782 There is a new hardware breakpoint for the watch command for sparclite
5783 targets. See gdb/sparclite/hw_breakpoint.note.
5785 Hardware watchpoints are also now supported under GNU/Linux.
5789 Annotations have been added. These are for use with graphical interfaces,
5790 and are still experimental. Currently only gdba.el uses these.
5792 * Improved Irix 5 support
5794 GDB now works properly with Irix 5.2.
5796 * Improved HPPA support
5798 GDB now works properly with the latest GCC and GAS.
5800 * New native configurations
5802 Sequent PTX4 i[34]86-sequent-ptx4
5803 HPPA running OSF/1 hppa*-*-osf*
5804 Atari TT running SVR4 m68*-*-sysv4*
5805 RS/6000 LynxOS rs6000-*-lynxos*
5809 OS/9000 i[34]86-*-os9k
5810 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
5813 * Hitachi SH7000 and E7000-PC ICE support
5815 There is now support for communicating with the Hitachi E7000-PC ICE.
5816 This is available automatically when GDB is configured for the SH.
5820 As usual, a variety of small fixes and improvements, both generic
5821 and configuration-specific. See the ChangeLog for more detail.
5823 *** Changes in GDB-4.12:
5825 * Irix 5 is now supported
5829 GDB-4.12 on the HPPA has a number of changes which make it unable
5830 to debug the output from the currently released versions of GCC and
5831 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
5832 of GCC and GAS, versions of these tools designed to work with GDB-4.12
5833 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
5836 *** Changes in GDB-4.11:
5838 * User visible changes:
5842 The "set remotedebug" option is now consistent between the mips remote
5843 target, remote targets using the gdb-specific protocol, UDI (AMD's
5844 debug protocol for the 29k) and the 88k bug monitor. It is now an
5845 integer specifying a debug level (normally 0 or 1, but 2 means more
5846 debugging info for the mips target).
5848 * DEC Alpha native support
5850 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
5851 debug info, but GDB works fairly well with the DEC compiler and should
5852 work with a future GCC release. See the README file for a few
5853 Alpha-specific notes.
5855 * Preliminary thread implementation
5857 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
5859 * LynxOS native and target support for 386
5861 This release has been hosted on LynxOS 2.2, and also can be configured
5862 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
5865 * Improvements in C++ mangling/demangling.
5867 This release has much better g++ debugging, specifically in name
5868 mangling/demangling, virtual function calls, print virtual table,
5869 call methods, ...etc.
5871 *** Changes in GDB-4.10:
5873 * User visible changes:
5875 Remote debugging using the GDB-specific (`target remote') protocol now
5876 supports the `load' command. This is only useful if you have some
5877 other way of getting the stub to the target system, and you can put it
5878 somewhere in memory where it won't get clobbered by the download.
5880 Filename completion now works.
5882 When run under emacs mode, the "info line" command now causes the
5883 arrow to point to the line specified. Also, "info line" prints
5884 addresses in symbolic form (as well as hex).
5886 All vxworks based targets now support a user settable option, called
5887 vxworks-timeout. This option represents the number of seconds gdb
5888 should wait for responses to rpc's. You might want to use this if
5889 your vxworks target is, perhaps, a slow software simulator or happens
5890 to be on the far side of a thin network line.
5894 This release contains support for using a DEC alpha as a GDB host for
5895 cross debugging. Native alpha debugging is not supported yet.
5898 *** Changes in GDB-4.9:
5902 This is the first GDB release which is accompanied by a matching testsuite.
5903 The testsuite requires installation of dejagnu, which should be available
5904 via ftp from most sites that carry GNU software.
5908 'Cfront' style demangling has had its name changed to 'ARM' style, to
5909 emphasize that it was written from the specifications in the C++ Annotated
5910 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
5911 disclaimers, it still generated too much confusion with users attempting to
5912 use gdb with AT&T cfront.
5916 GDB now uses a standard remote interface to a simulator library.
5917 So far, the library contains simulators for the Zilog Z8001/2, the
5918 Hitachi H8/300, H8/500 and Super-H.
5920 * New targets supported
5922 H8/300 simulator h8300-hitachi-hms or h8300hms
5923 H8/500 simulator h8500-hitachi-hms or h8500hms
5924 SH simulator sh-hitachi-hms or sh
5925 Z8000 simulator z8k-zilog-none or z8ksim
5926 IDT MIPS board over serial line mips-idt-ecoff
5928 Cross-debugging to GO32 targets is supported. It requires a custom
5929 version of the i386-stub.c module which is integrated with the
5930 GO32 memory extender.
5932 * New remote protocols
5934 MIPS remote debugging protocol.
5936 * New source languages supported
5938 This version includes preliminary support for Chill, a Pascal like language
5939 used by telecommunications companies. Chill support is also being integrated
5940 into the GNU compiler, but we don't know when it will be publically available.
5943 *** Changes in GDB-4.8:
5945 * HP Precision Architecture supported
5947 GDB now supports HP PA-RISC machines running HPUX. A preliminary
5948 version of this support was available as a set of patches from the
5949 University of Utah. GDB does not support debugging of programs
5950 compiled with the HP compiler, because HP will not document their file
5951 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
5952 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
5954 Many problems in the preliminary version have been fixed.
5956 * Faster and better demangling
5958 We have improved template demangling and fixed numerous bugs in the GNU style
5959 demangler. It can now handle type modifiers such as `static' or `const'. Wide
5960 character types (wchar_t) are now supported. Demangling of each symbol is now
5961 only done once, and is cached when the symbol table for a file is read in.
5962 This results in a small increase in memory usage for C programs, a moderate
5963 increase in memory usage for C++ programs, and a fantastic speedup in
5966 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
5967 from the specifications in the Annotated Reference Manual, which AT&T's
5968 compiler does not actually implement.
5970 * G++ multiple inheritance compiler problem
5972 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
5973 inheritance lattices was reworked to properly discover ambiguities. We
5974 recently found an example which causes this new algorithm to fail in a
5975 very subtle way, producing bad debug information for those classes.
5976 The file 'gcc.patch' (in this directory) can be applied to gcc to
5977 circumvent the problem. A future GCC release will contain a complete
5980 The previous G++ debug info problem (mentioned below for the gdb-4.7
5981 release) is fixed in gcc version 2.3.2.
5983 * Improved configure script
5985 The `configure' script will now attempt to guess your system type if
5986 you don't supply a host system type. The old scheme of supplying a
5987 host system triplet is preferable over using this. All the magic is
5988 done in the new `config.guess' script. Examine it for details.
5990 We have also brought our configure script much more in line with the FSF's
5991 version. It now supports the --with-xxx options. In particular,
5992 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
5993 The resulting GDB will not be able to read arbitrary object file formats --
5994 only the format ``expected'' to be used on the configured target system.
5995 We hope to make this the default in a future release.
5997 * Documentation improvements
5999 There's new internal documentation on how to modify GDB, and how to
6000 produce clean changes to the code. We implore people to read it
6001 before submitting changes.
6003 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6004 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6005 `info' files are also provided. To build `info' files from scratch,
6006 you will need the latest `makeinfo' release, which will be available in
6007 a future texinfo-X.Y release.
6009 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6010 We're not sure exactly which versions have this problem, but it has
6011 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6012 or better. If that isn't possible, there is a patch in
6013 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6014 around this problem.
6018 GDB now supports array constants that can be used in expressions typed in by
6019 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6020 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6023 The new directory `gdb/sparclite' contains a program that demonstrates
6024 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6026 * New native hosts supported
6028 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6029 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6031 * New targets supported
6033 AMD 29k family via UDI a29k-amd-udi or udi29k
6035 * New file formats supported
6037 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6038 HPUX core files, and SCO 3.2v2 core files.
6042 Attaching to processes now works again; thanks for the many bug reports.
6044 We have also stomped on a bunch of core dumps caused by
6045 printf_filtered("%s") problems.
6047 We eliminated a copyright problem on the rpc and ptrace header files
6048 for VxWorks, which was discovered at the last minute during the 4.7
6049 release. You should now be able to build a VxWorks GDB.
6051 You can now interrupt gdb while an attached process is running. This
6052 will cause the attached process to stop, and give control back to GDB.
6054 We fixed problems caused by using too many file descriptors
6055 for reading symbols from object files and libraries. This was
6056 especially a problem for programs that used many (~100) shared
6059 The `step' command now only enters a subroutine if there is line number
6060 information for the subroutine. Otherwise it acts like the `next'
6061 command. Previously, `step' would enter subroutines if there was
6062 any debugging information about the routine. This avoids problems
6063 when using `cc -g1' on MIPS machines.
6065 * Internal improvements
6067 GDB's internal interfaces have been improved to make it easier to support
6068 debugging of multiple languages in the future.
6070 GDB now uses a common structure for symbol information internally.
6071 Minimal symbols (derived from linkage symbols in object files), partial
6072 symbols (from a quick scan of debug information), and full symbols
6073 contain a common subset of information, making it easier to write
6074 shared code that handles any of them.
6076 * New command line options
6078 We now accept --silent as an alias for --quiet.
6082 The memory-mapped-malloc library is now licensed under the GNU Library
6083 General Public License.
6085 *** Changes in GDB-4.7:
6087 * Host/native/target split
6089 GDB has had some major internal surgery to untangle the support for
6090 hosts and remote targets. Now, when you configure GDB for a remote
6091 target, it will no longer load in all of the support for debugging
6092 local programs on the host. When fully completed and tested, this will
6093 ensure that arbitrary host/target combinations are possible.
6095 The primary conceptual shift is to separate the non-portable code in
6096 GDB into three categories. Host specific code is required any time GDB
6097 is compiled on that host, regardless of the target. Target specific
6098 code relates to the peculiarities of the target, but can be compiled on
6099 any host. Native specific code is everything else: it can only be
6100 built when the host and target are the same system. Child process
6101 handling and core file support are two common `native' examples.
6103 GDB's use of /proc for controlling Unix child processes is now cleaner.
6104 It has been split out into a single module under the `target_ops' vector,
6105 plus two native-dependent functions for each system that uses /proc.
6107 * New hosts supported
6109 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6110 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6111 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6113 * New targets supported
6115 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6116 68030 and CPU32 m68030-*-*, m68332-*-*
6118 * New native hosts supported
6120 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6121 (386bsd is not well tested yet)
6122 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6124 * New file formats supported
6126 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6127 supports reading of `a.out.adobe' object files, which are an a.out
6128 format extended with minimal information about multiple sections.
6132 `show copying' is the same as the old `info copying'.
6133 `show warranty' is the same as `info warrantee'.
6134 These were renamed for consistency. The old commands continue to work.
6136 `info handle' is a new alias for `info signals'.
6138 You can now define pre-command hooks, which attach arbitrary command
6139 scripts to any command. The commands in the hook will be executed
6140 prior to the user's command. You can also create a hook which will be
6141 executed whenever the program stops. See gdb.texinfo.
6145 We now deal with Cfront style name mangling, and can even extract type
6146 info from mangled symbols. GDB can automatically figure out which
6147 symbol mangling style your C++ compiler uses.
6149 Calling of methods and virtual functions has been improved as well.
6153 The crash that occured when debugging Sun Ansi-C compiled binaries is
6154 fixed. This was due to mishandling of the extra N_SO stabs output
6157 We also finally got Ultrix 4.2 running in house, and fixed core file
6158 support, with help from a dozen people on the net.
6160 John M. Farrell discovered that the reason that single-stepping was so
6161 slow on all of the Mips based platforms (primarily SGI and DEC) was
6162 that we were trying to demangle and lookup a symbol used for internal
6163 purposes on every instruction that was being stepped through. Changing
6164 the name of that symbol so that it couldn't be mistaken for a C++
6165 mangled symbol sped things up a great deal.
6167 Rich Pixley sped up symbol lookups in general by getting much smarter
6168 about when C++ symbol mangling is necessary. This should make symbol
6169 completion (TAB on the command line) much faster. It's not as fast as
6170 we'd like, but it's significantly faster than gdb-4.6.
6174 A new user controllable variable 'call_scratch_address' can
6175 specify the location of a scratch area to be used when GDB
6176 calls a function in the target. This is necessary because the
6177 usual method of putting the scratch area on the stack does not work
6178 in systems that have separate instruction and data spaces.
6180 We integrated changes to support the 29k UDI (Universal Debugger
6181 Interface), but discovered at the last minute that we didn't have all
6182 of the appropriate copyright paperwork. We are working with AMD to
6183 resolve this, and hope to have it available soon.
6187 We have sped up the remote serial line protocol, especially for targets
6188 with lots of registers. It now supports a new `expedited status' ('T')
6189 message which can be used in place of the existing 'S' status message.
6190 This allows the remote stub to send only the registers that GDB
6191 needs to make a quick decision about single-stepping or conditional
6192 breakpoints, eliminating the need to fetch the entire register set for
6193 each instruction being stepped through.
6195 The GDB remote serial protocol now implements a write-through cache for
6196 registers, only re-reading the registers if the target has run.
6198 There is also a new remote serial stub for SPARC processors. You can
6199 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6200 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6201 processor with a serial port.
6205 Configure.in files have become much easier to read and modify. A new
6206 `table driven' format makes it more obvious what configurations are
6207 supported, and what files each one uses.
6211 There is a new opcodes library which will eventually contain all of the
6212 disassembly routines and opcode tables. At present, it only contains
6213 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6214 disassembler (binutils/objdump) to share these routines.
6216 The libiberty library is now copylefted under the GNU Library General
6217 Public License. This allows more liberal use, and was done so libg++
6218 can use it. This makes no difference to GDB, since the Library License
6219 grants all the rights from the General Public License.
6223 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6224 reference to the stabs symbol info used by the debugger. It is (as far
6225 as we know) the only published document on this fascinating topic. We
6226 encourage you to read it, compare it to the stabs information on your
6227 system, and send improvements on the document in general (to
6228 bug-gdb@prep.ai.mit.edu).
6230 And, of course, many bugs have been fixed.
6233 *** Changes in GDB-4.6:
6235 * Better support for C++ function names
6237 GDB now accepts as input the "demangled form" of C++ overloaded function
6238 names and member function names, and can do command completion on such names
6239 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6240 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6241 Make use of command completion, it is your friend.
6243 GDB also now accepts a variety of C++ mangled symbol formats. They are
6244 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6245 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6246 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6247 for the list of formats.
6249 * G++ symbol mangling problem
6251 Recent versions of gcc have a bug in how they emit debugging information for
6252 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6253 directory) can be applied to gcc to fix the problem. Alternatively, if you
6254 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6255 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6256 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6259 * New 'maintenance' command
6261 All of the commands related to hacking GDB internals have been moved out of
6262 the main command set, and now live behind the 'maintenance' command. This
6263 can also be abbreviated as 'mt'. The following changes were made:
6265 dump-me -> maintenance dump-me
6266 info all-breakpoints -> maintenance info breakpoints
6267 printmsyms -> maintenance print msyms
6268 printobjfiles -> maintenance print objfiles
6269 printpsyms -> maintenance print psymbols
6270 printsyms -> maintenance print symbols
6272 The following commands are new:
6274 maintenance demangle Call internal GDB demangler routine to
6275 demangle a C++ link name and prints the result.
6276 maintenance print type Print a type chain for a given symbol
6278 * Change to .gdbinit file processing
6280 We now read the $HOME/.gdbinit file before processing the argv arguments
6281 (e.g. reading symbol files or core files). This allows global parameters to
6282 be set, which will apply during the symbol reading. The ./.gdbinit is still
6283 read after argv processing.
6285 * New hosts supported
6287 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6289 GNU/Linux support i386-unknown-linux or linux
6291 We are also including code to support the HP/PA running BSD and HPUX. This
6292 is almost guaranteed not to work, as we didn't have time to test or build it
6293 for this release. We are including it so that the more adventurous (or
6294 masochistic) of you can play with it. We also had major problems with the
6295 fact that the compiler that we got from HP doesn't support the -g option.
6298 * New targets supported
6300 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6302 * More smarts about finding #include files
6304 GDB now remembers the compilation directory for all include files, and for
6305 all files from which C is generated (like yacc and lex sources). This
6306 greatly improves GDB's ability to find yacc/lex sources, and include files,
6307 especially if you are debugging your program from a directory different from
6308 the one that contains your sources.
6310 We also fixed a bug which caused difficulty with listing and setting
6311 breakpoints in include files which contain C code. (In the past, you had to
6312 try twice in order to list an include file that you hadn't looked at before.)
6314 * Interesting infernals change
6316 GDB now deals with arbitrary numbers of sections, where the symbols for each
6317 section must be relocated relative to that section's landing place in the
6318 target's address space. This work was needed to support ELF with embedded
6319 stabs used by Solaris-2.0.
6321 * Bug fixes (of course!)
6323 There have been loads of fixes for the following things:
6324 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6325 i960, stabs, DOS(GO32), procfs, etc...
6327 See the ChangeLog for details.
6329 *** Changes in GDB-4.5:
6331 * New machines supported (host and target)
6333 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6335 SGI Irix-4.x mips-sgi-irix4 or iris4
6337 * New malloc package
6339 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6340 Mmalloc is capable of handling mutiple heaps of memory. It is also
6341 capable of saving a heap to a file, and then mapping it back in later.
6342 This can be used to greatly speedup the startup of GDB by using a
6343 pre-parsed symbol table which lives in a mmalloc managed heap. For
6344 more details, please read mmalloc/mmalloc.texi.
6348 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6349 'help info proc' for details.
6351 * MIPS ecoff symbol table format
6353 The code that reads MIPS symbol table format is now supported on all hosts.
6354 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6357 * File name changes for MS-DOS
6359 Many files in the config directories have been renamed to make it easier to
6360 support GDB on MS-DOSe systems (which have very restrictive file name
6361 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6362 environment) is close to working but has some remaining problems. Note
6363 that debugging of DOS programs is not supported, due to limitations
6364 in the ``operating system'', but it can be used to host cross-debugging.
6366 * Cross byte order fixes
6368 Many fixes have been made to support cross debugging of Sparc and MIPS
6369 targets from hosts whose byte order differs.
6371 * New -mapped and -readnow options
6373 If memory-mapped files are available on your system through the 'mmap'
6374 system call, you can use the -mapped option on the `file' or
6375 `symbol-file' commands to cause GDB to write the symbols from your
6376 program into a reusable file. If the program you are debugging is
6377 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6378 Future GDB debugging sessions will notice the presence of this file,
6379 and will quickly map in symbol information from it, rather than reading
6380 the symbol table from the executable program. Using the '-mapped'
6381 option in a GDB `file' or `symbol-file' command has the same effect as
6382 starting GDB with the '-mapped' command-line option.
6384 You can cause GDB to read the entire symbol table immediately by using
6385 the '-readnow' option with any of the commands that load symbol table
6386 information (or on the GDB command line). This makes the command
6387 slower, but makes future operations faster.
6389 The -mapped and -readnow options are typically combined in order to
6390 build a `fred.syms' file that contains complete symbol information.
6391 A simple GDB invocation to do nothing but build a `.syms' file for future
6394 gdb -batch -nx -mapped -readnow programname
6396 The `.syms' file is specific to the host machine on which GDB is run.
6397 It holds an exact image of GDB's internal symbol table. It cannot be
6398 shared across multiple host platforms.
6400 * longjmp() handling
6402 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6403 siglongjmp() without losing control. This feature has not yet been ported to
6404 all systems. It currently works on many 386 platforms, all MIPS-based
6405 platforms (SGI, DECstation, etc), and Sun3/4.
6409 Preliminary work has been put in to support the new Solaris OS from Sun. At
6410 this time, it can control and debug processes, but it is not capable of
6415 As always, many many bug fixes. The major areas were with g++, and mipsread.
6416 People using the MIPS-based platforms should experience fewer mysterious
6417 crashes and trashed symbol tables.
6419 *** Changes in GDB-4.4:
6421 * New machines supported (host and target)
6423 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6425 BSD Reno on Vax vax-dec-bsd
6426 Ultrix on Vax vax-dec-ultrix
6428 * New machines supported (target)
6430 AMD 29000 embedded, using EBMON a29k-none-none
6434 GDB continues to improve its handling of C++. `References' work better.
6435 The demangler has also been improved, and now deals with symbols mangled as
6436 per the Annotated C++ Reference Guide.
6438 GDB also now handles `stabs' symbol information embedded in MIPS
6439 `ecoff' symbol tables. Since the ecoff format was not easily
6440 extensible to handle new languages such as C++, this appeared to be a
6441 good way to put C++ debugging info into MIPS binaries. This option
6442 will be supported in the GNU C compiler, version 2, when it is
6445 * New features for SVR4
6447 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6448 shared libraries. Debugging dynamically linked programs should present
6449 only minor differences from debugging statically linked programs.
6451 The `info proc' command will print out information about any process
6452 on an SVR4 system (including the one you are debugging). At the moment,
6453 it prints the address mappings of the process.
6455 If you bring up GDB on another SVR4 system, please send mail to
6456 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6458 * Better dynamic linking support in SunOS
6460 Reading symbols from shared libraries which contain debugging symbols
6461 now works properly. However, there remain issues such as automatic
6462 skipping of `transfer vector' code during function calls, which
6463 make it harder to debug code in a shared library, than to debug the
6464 same code linked statically.
6468 GDB is now using the latest `getopt' routines from the FSF. This
6469 version accepts the -- prefix for options with long names. GDB will
6470 continue to accept the old forms (-option and +option) as well.
6471 Various single letter abbreviations for options have been explicity
6472 added to the option table so that they won't get overshadowed in the
6473 future by other options that begin with the same letter.
6477 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6478 Many assorted bugs have been handled. Many more remain to be handled.
6479 See the various ChangeLog files (primarily in gdb and bfd) for details.
6482 *** Changes in GDB-4.3:
6484 * New machines supported (host and target)
6486 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6487 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6488 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6490 * Almost SCO Unix support
6492 We had hoped to support:
6493 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6494 (except for core file support), but we discovered very late in the release
6495 that it has problems with process groups that render gdb unusable. Sorry
6496 about that. I encourage people to fix it and post the fixes.
6498 * Preliminary ELF and DWARF support
6500 GDB can read ELF object files on System V Release 4, and can handle
6501 debugging records for C, in DWARF format, in ELF files. This support
6502 is preliminary. If you bring up GDB on another SVR4 system, please
6503 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
6508 GDB now uses the latest `readline' library. One user-visible change
6509 is that two tabs will list possible command completions, which previously
6510 required typing M-? (meta-question mark, or ESC ?).
6514 The `stepi' bug that many of you noticed has been squashed.
6515 Many bugs in C++ have been handled. Many more remain to be handled.
6516 See the various ChangeLog files (primarily in gdb and bfd) for details.
6518 * State of the MIPS world (in case you wondered):
6520 GDB can understand the symbol tables emitted by the compilers
6521 supplied by most vendors of MIPS-based machines, including DEC. These
6522 symbol tables are in a format that essentially nobody else uses.
6524 Some versions of gcc come with an assembler post-processor called
6525 mips-tfile. This program is required if you want to do source-level
6526 debugging of gcc-compiled programs. I believe FSF does not ship
6527 mips-tfile with gcc version 1, but it will eventually come with gcc
6530 Debugging of g++ output remains a problem. g++ version 1.xx does not
6531 really support it at all. (If you're lucky, you should be able to get
6532 line numbers and stack traces to work, but no parameters or local
6533 variables.) With some work it should be possible to improve the
6536 When gcc version 2 is released, you will have somewhat better luck.
6537 However, even then you will get confusing results for inheritance and
6540 We will eventually provide full debugging of g++ output on
6541 DECstations. This will probably involve some kind of stabs-in-ecoff
6542 encapulation, but the details have not been worked out yet.
6545 *** Changes in GDB-4.2:
6547 * Improved configuration
6549 Only one copy of `configure' exists now, and it is not self-modifying.
6550 Porting BFD is simpler.
6554 The `step' and `next' commands now only stop at the first instruction
6555 of a source line. This prevents the multiple stops that used to occur
6556 in switch statements, for-loops, etc. `Step' continues to stop if a
6557 function that has debugging information is called within the line.
6561 Lots of small bugs fixed. More remain.
6563 * New host supported (not target)
6565 Intel 386 PC clone running Mach i386-none-mach
6568 *** Changes in GDB-4.1:
6570 * Multiple source language support
6572 GDB now has internal scaffolding to handle several source languages.
6573 It determines the type of each source file from its filename extension,
6574 and will switch expression parsing and number formatting to match the
6575 language of the function in the currently selected stack frame.
6576 You can also specifically set the language to be used, with
6577 `set language c' or `set language modula-2'.
6581 GDB now has preliminary support for the GNU Modula-2 compiler,
6582 currently under development at the State University of New York at
6583 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
6584 continue through the fall of 1991 and into 1992.
6586 Other Modula-2 compilers are currently not supported, and attempting to
6587 debug programs compiled with them will likely result in an error as the
6588 symbol table is read. Feel free to work on it, though!
6590 There are hooks in GDB for strict type checking and range checking,
6591 in the `Modula-2 philosophy', but they do not currently work.
6595 GDB can now write to executable and core files (e.g. patch
6596 a variable's value). You must turn this switch on, specify
6597 the file ("exec foo" or "core foo"), *then* modify it, e.g.
6598 by assigning a new value to a variable. Modifications take
6601 * Automatic SunOS shared library reading
6603 When you run your program, GDB automatically determines where its
6604 shared libraries (if any) have been loaded, and reads their symbols.
6605 The `share' command is no longer needed. This also works when
6606 examining core files.
6610 You can specify the number of lines that the `list' command shows.
6613 * New machines supported (host and target)
6615 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
6616 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
6617 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
6619 * New hosts supported (not targets)
6621 IBM RT/PC: romp-ibm-aix or rtpc
6623 * New targets supported (not hosts)
6625 AMD 29000 embedded with COFF a29k-none-coff
6626 AMD 29000 embedded with a.out a29k-none-aout
6627 Ultracomputer remote kernel debug a29k-nyu-kern
6629 * New remote interfaces
6635 *** Changes in GDB-4.0:
6639 Wide output is wrapped at good places to make the output more readable.
6641 Gdb now supports cross-debugging from a host machine of one type to a
6642 target machine of another type. Communication with the target system
6643 is over serial lines. The ``target'' command handles connecting to the
6644 remote system; the ``load'' command will download a program into the
6645 remote system. Serial stubs for the m68k and i386 are provided. Gdb
6646 also supports debugging of realtime processes running under VxWorks,
6647 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
6648 stub on the target system.
6650 New CPUs supported include the AMD 29000 and Intel 960.
6652 GDB now reads object files and symbol tables via a ``binary file''
6653 library, which allows a single copy of GDB to debug programs of multiple
6654 object file types such as a.out and coff.
6656 There is now a GDB reference card in "doc/refcard.tex". (Make targets
6657 refcard.dvi and refcard.ps are available to format it).
6660 * Control-Variable user interface simplified
6662 All variables that control the operation of the debugger can be set
6663 by the ``set'' command, and displayed by the ``show'' command.
6665 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
6666 ``Show prompt'' produces the response:
6667 Gdb's prompt is new-gdb=>.
6669 What follows are the NEW set commands. The command ``help set'' will
6670 print a complete list of old and new set commands. ``help set FOO''
6671 will give a longer description of the variable FOO. ``show'' will show
6672 all of the variable descriptions and their current settings.
6674 confirm on/off: Enables warning questions for operations that are
6675 hard to recover from, e.g. rerunning the program while
6676 it is already running. Default is ON.
6678 editing on/off: Enables EMACS style command line editing
6679 of input. Previous lines can be recalled with
6680 control-P, the current line can be edited with control-B,
6681 you can search for commands with control-R, etc.
6684 history filename NAME: NAME is where the gdb command history
6685 will be stored. The default is .gdb_history,
6686 or the value of the environment variable
6689 history size N: The size, in commands, of the command history. The
6690 default is 256, or the value of the environment variable
6693 history save on/off: If this value is set to ON, the history file will
6694 be saved after exiting gdb. If set to OFF, the
6695 file will not be saved. The default is OFF.
6697 history expansion on/off: If this value is set to ON, then csh-like
6698 history expansion will be performed on
6699 command line input. The default is OFF.
6701 radix N: Sets the default radix for input and output. It can be set
6702 to 8, 10, or 16. Note that the argument to "radix" is interpreted
6703 in the current radix, so "set radix 10" is always a no-op.
6705 height N: This integer value is the number of lines on a page. Default
6706 is 24, the current `stty rows'' setting, or the ``li#''
6707 setting from the termcap entry matching the environment
6710 width N: This integer value is the number of characters on a line.
6711 Default is 80, the current `stty cols'' setting, or the ``co#''
6712 setting from the termcap entry matching the environment
6715 Note: ``set screensize'' is obsolete. Use ``set height'' and
6716 ``set width'' instead.
6718 print address on/off: Print memory addresses in various command displays,
6719 such as stack traces and structure values. Gdb looks
6720 more ``symbolic'' if you turn this off; it looks more
6721 ``machine level'' with it on. Default is ON.
6723 print array on/off: Prettyprint arrays. New convenient format! Default
6726 print demangle on/off: Print C++ symbols in "source" form if on,
6729 print asm-demangle on/off: Same, for assembler level printouts
6732 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
6735 * Support for Epoch Environment.
6737 The epoch environment is a version of Emacs v18 with windowing. One
6738 new command, ``inspect'', is identical to ``print'', except that if you
6739 are running in the epoch environment, the value is printed in its own
6743 * Support for Shared Libraries
6745 GDB can now debug programs and core files that use SunOS shared libraries.
6746 Symbols from a shared library cannot be referenced
6747 before the shared library has been linked with the program (this
6748 happens after you type ``run'' and before the function main() is entered).
6749 At any time after this linking (including when examining core files
6750 from dynamically linked programs), gdb reads the symbols from each
6751 shared library when you type the ``sharedlibrary'' command.
6752 It can be abbreviated ``share''.
6754 sharedlibrary REGEXP: Load shared object library symbols for files
6755 matching a unix regular expression. No argument
6756 indicates to load symbols for all shared libraries.
6758 info sharedlibrary: Status of loaded shared libraries.
6763 A watchpoint stops execution of a program whenever the value of an
6764 expression changes. Checking for this slows down execution
6765 tremendously whenever you are in the scope of the expression, but is
6766 quite useful for catching tough ``bit-spreader'' or pointer misuse
6767 problems. Some machines such as the 386 have hardware for doing this
6768 more quickly, and future versions of gdb will use this hardware.
6770 watch EXP: Set a watchpoint (breakpoint) for an expression.
6772 info watchpoints: Information about your watchpoints.
6774 delete N: Deletes watchpoint number N (same as breakpoints).
6775 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
6776 enable N: Re-enables watchpoint number N (same as breakpoints).
6779 * C++ multiple inheritance
6781 When used with a GCC version 2 compiler, GDB supports multiple inheritance
6784 * C++ exception handling
6786 Gdb now supports limited C++ exception handling. Besides the existing
6787 ability to breakpoint on an exception handler, gdb can breakpoint on
6788 the raising of an exception (before the stack is peeled back to the
6791 catch FOO: If there is a FOO exception handler in the dynamic scope,
6792 set a breakpoint to catch exceptions which may be raised there.
6793 Multiple exceptions (``catch foo bar baz'') may be caught.
6795 info catch: Lists all exceptions which may be caught in the
6796 current stack frame.
6799 * Minor command changes
6801 The command ``call func (arg, arg, ...)'' now acts like the print
6802 command, except it does not print or save a value if the function's result
6803 is void. This is similar to dbx usage.
6805 The ``up'' and ``down'' commands now always print the frame they end up
6806 at; ``up-silently'' and `down-silently'' can be used in scripts to change
6807 frames without printing.
6809 * New directory command
6811 'dir' now adds directories to the FRONT of the source search path.
6812 The path starts off empty. Source files that contain debug information
6813 about the directory in which they were compiled can be found even
6814 with an empty path; Sun CC and GCC include this information. If GDB can't
6815 find your source file in the current directory, type "dir .".
6817 * Configuring GDB for compilation
6819 For normal use, type ``./configure host''. See README or gdb.texinfo
6822 GDB now handles cross debugging. If you are remotely debugging between
6823 two different machines, type ``./configure host -target=targ''.
6824 Host is the machine where GDB will run; targ is the machine
6825 where the program that you are debugging will run.
projects / external / binutils.git / blob